Ischemic nephropathy/azotemic renovascular disease.
Atherosclerotic renal vascular disease can impair kidney perfusion and lead to deterioration of kidney function. The mechanisms by which reversible tissue injury becomes irreversible are not yet certain, although multiple pathways for activation of inflammatory cytokines and tissue fibrosis have been identified. The clinical hallmark of this disorder is loss of glomerular filtration beyond renal artery stenosis affecting the entire renal mass, usually associated with progressive hypertension and fluid retention. Some investigators believe that 12% to 18% of patients reaching end-stage renal disease in western countries may have lost kidney function because of azotemic renovascular disease. This is an important disorder to identify, because reduction of arterial pressure from antihypertensive therapy may further reduce kidney perfusion. Although administration of angiotensin-converting enzyme (ACE) inhibitors and angiotensin II antagonists lead to functional loss of glomerular filtration rate (GFR) beyond a stenotic lesion because of the removal of efferent actions of angiotensin II, other antihypertensive agents reduce renal perfusion also. Restoration of renal blood flow by surgical or endovascular methods can prevent progressive disease and sometimes improves renal function. However, clinical series commonly indicate that some patients lose further kidney function after revascularization. This may be explained partly by undetected renal atheremboli or other toxicity related to vascular repair. Hence, selection of patients for renal revascularization requires careful consideration of comorbid disease risk and the balance of risks and benefits regarding progressive renal disease. Searching for better methods of identifying those individuals at risk for irreversible loss of renal function and who might benefit from vascular repair is a high research priority.


Criticality of forcing directions on the fragmentation and resilience of grid networks.
A general framework for probing the dynamic evolution of spatial networks comprised of nodes applying force amongst each other is presented. Aside from the already reported magnitude of forces and elongation thresholds, we show that preservation of links in a network is also crucially dependent on how nodes are connected and how edges are directed. We demonstrate that the time it takes for the networks to reach its equilibrium network structure follows a robust power law relationship consistent with Basquin's law with an exponent that can be tuned by changing only the force directions. Further, we illustrate that networks with different connection structures, node positions and edge directions have different Basquin's exponent which can be used to distinguish spatial directed networks from each other. Using an extensive waiting time simulation that spans up to over 16 orders of magnitude, we establish that the presence of memory combined with the scale-free bursty dynamics of edge breaking at the micro level leads to the evident macroscopic power law distribution of network lifetime.


Human-induced changes in the hydrology of the western United States.
Observations have shown that the hydrological cycle of the western United States changed significantly over the last half of the 20th century. We present a regional, multivariable climate change detection and attribution study, using a high-resolution hydrologic model forced by global climate models, focusing on the changes that have already affected this primarily arid region with a large and growing population. The results show that up to 60% of the climate-related trends of river flow, winter air temperature, and snow pack between 1950 and 1999 are human-induced. These results are robust to perturbation of study variates and methods. They portend, in conjunction with previous work, a coming crisis in water supply for the western United States.


Resolution of Sickle Cell Crisis Following Administration of Amiodarone.
Sickle cell disease is a prevalent hematologic condition, but some of the factors that lead to erythrocyte sickling are not fully known. A 58-year-old male patient with a history of sickle cell disease (SCD) and paroxysmal atrial fibrillation was transferred from an outside hospital for further management of refractory sickle cell crisis with acute chest syndrome. Before transfer, the patient received antibiotics and multiple packed red blood cell (pRBC) transfusions, with minimal effect on symptoms or anemia. After transfer, the patient developed rapid supraventricular tachycardia and atrial fibrillation (rates >160) with a drop in blood pressure. He was started on IV amiodarone. His heart rate was subsequently better controlled and converted to sinus rhythm the following day. Three days following initiation of amiodarone, the patient, with a hemoglobin count of 6.4 g/dl, required one additional unit of pRBC. On the fourth day, the patient's hemoglobin count rose to 9.4 g/dl, and he reported a marked improvement in symptoms. The improvements in symptoms and hemoglobin count were sustained, and the patient was discharged two days later. This remarkable improvement in anemia and symptoms triggered a search for potential causes. Amiodarone is a complex drug shown to have effects on multiple cell types, including erythrocytes. A recent preclinical study demonstrated reduced sickling and improved anemia in a murine model of SCD. This case report raises the possibility that amiodarone may have contributed to the rapid improvement in anemia and should be further explored in clinical trials. Prior studies support a link between erythrocyte sickling and membrane lipid composition.Amiodarone may impact erythrocyte pathophysiology by increasing cellular lipids including bis(mono)acylglycerol phosphate (BMP).Drugs with effects on erythrocyte lipid fractions may be beneficial during sickle cell crises.


Choroidal neovascularization in the rat induced by adenovirus mediated expression of vascular endothelial growth factor.
To determine the effects of an adenovirus vector encoding vascular endothelial growth factor(165) (Ad.VEGF) delivered to the subretinal space in the rat. An E1-deleted adenoviral vector encoding VEGF was injected into the subretinal space of Long-Evans rats. Immunohistochemistry identified VEGF expression. Histopathologic changes in the retina were determined by light and electron microscopy, immunohistochemistry, fluorescein angiography, and examination of wholemounts of choroid and retina. Increased expression of VEGF only in the retinal pigment epithelium (RPE) was detected after Ad.VEGF injection. Histopathology of these eyes revealed minimal subretinal exudation at 1 week followed by the appearance of vascular structures in the subretinal space by week 2, which persisted up to 4 weeks. Shortening of photoreceptor outer segments and reduction of the outer nuclear layer were present overlying areas of neovascularization. Fluorescein angiography of animals injected with fluorescein-dextran revealed a deep complex of new vessels. Choroidal flatmounts showed new vessel formation, verified by detection of endothelial cells via immunohistochemistry, arising from the choroid with absence of change in the overlying retinal vasculature. Electron microscopy confirmed the presence of sub-RPE endothelial cells and pericytes and the loss of integrity of Bruch's membrane, and serial sectioning demonstrated choroidal vascular growth through Bruch's membrane. These results support the hypothesis that overexpression of VEGF from RPE cells is capable of inducing choroidal neovascularization in the rat and provide a framework for further examining angiogenic processes in the RPE-choroid complex.


Functional selectivity of nociceptin/orphanin FQ peptide receptor partial agonists on cardiovascular and renal function.
The opioid-like peptide nociceptin/orphanin FQ (N/OFQ) produces marked cardiovascular and renal responses after central or peripheral administration in rats. Due to their ability to behave as full/partial agonists or antagonists in different cellular and tissue assays, the present studies were performed to determine how compounds classified as N/OFQ peptide (NOP) receptor partial agonists ([F/G]N/OFQ(1-13)-NH(2), Ac-RYYRIK-NH(2), and Ac-RYYRWK-NH(2)) affect cardiovascular and renal function in vivo. In conscious Sprague-Dawley rats, intracerebroventricular (i.c.v.) administration of each of the three NOP receptor ligands produced profound cardiovascular (depressor), renal excretory (water diuresis), and renal sympathetic nerve activity (inhibitory) responses that were similar to those produced by i.c.v. injection of the native ligand N/OFQ. In contrast, in other groups of rats, the intravenous (i.v.) bolus injection of these same NOP receptor ligands produced responses unlike N/OFQ; N/OFQ evoked an immediate and profound bradycardia and hypotension with no change in urine output, whereas all purported NOP receptor partial agonists elicited a subtle slow onset hypotension, no change in heart rate, and a marked water diuresis. In other studies, i.v. bolus pretreatment of rats with NOP receptor partial agonists prevented/attenuated the cardiovascular depressor effects produced by a subsequent i.v. bolus N/OFQ challenge without affecting the cardiovascular responses to i.c.v. N/OFQ. Together, these findings demonstrate that in conscious rats, NOP receptor partial agonists produce functionally selective effects on cardiovascular and renal function ranging from full agonist (i.c.v., cardiovascular depressor; i.c.v. and i.v., water diuresis), partial agonist (i.v., submaximal hypotension) to antagonist (i.v., blockade of N/OFQ-evoked bradycardia and hypotension) behavior.


Behavioural activation therapy for post-stroke depression: the BEADS feasibility RCT.
There is currently insufficient evidence for the clinical effectiveness and cost-effectiveness of psychological therapies for post-stroke depression. To evaluate the feasibility of undertaking a definitive trial to evaluate the clinical effectiveness and cost-effectiveness of behavioural activation (BA) compared with usual stroke care for treating post-stroke depression. Parallel-group, feasibility, multicentre, randomised controlled trial with nested qualitative research and a health economic evaluation. Acute and community stroke services in three sites in England. Community-dwelling adults 3 months to 5 years post stroke who are depressed, as determined by the Patient Health Questionnaire-9 (PHQ-9) or the Visual Analogue Mood Scales 'Sad' item. Exclusions: patients who are blind and/or deaf, have dementia, are unable to communicate in English, do not have mental capacity to consent, are receiving treatment for depression at the time of stroke onset or are currently receiving psychological intervention. Participants were randomised (1 : 1 ratio) to BA or usual stroke care. Randomisation was conducted using a computer-generated list with random permuted blocks of varying sizes, stratified by site. Participants and therapists were aware of the allocation, but outcome assessors were blind. The intervention arm received up to 15 sessions of BA over 4 months. BA aims to improve mood by increasing people's level of enjoyable or valued activities. The control arm received usual care only. Primary feasibility outcomes concerned feasibility of recruitment to the main trial, acceptability of research procedures and measures, appropriateness of baseline and outcome measures, retention of participants and potential value of conducting the definitive trial. Secondary feasibility outcomes concerned the delivery of the intervention. The primary clinical outcome 6 months post randomisation was the PHQ-9. Secondary clinical outcomes were Stroke Aphasic Depression Questionnaire - Hospital version, Nottingham Leisure Questionnaire, Nottingham Extended Activities of Daily Living, Carer Strain Index, EuroQol-5 Dimensions, five-level version and health-care resource use questionnaire. Forty-eight participants were recruited in 27 centre-months of recruitment, at a recruitment rate of 1.8 participants per centre per month. The 25 participants randomised to receive BA attended a mean of 8.5 therapy sessions [standard deviation (SD) 4.4 therapy sessions]; 23 participants were allocated to usual care. Outcome assessments were completed by 39 (81%) participants (BA, n = 18; usual care, n = 21). Mean PHQ-9 scores at 6-month follow-up were 10.1 points (SD 6.9 points) and 14.4 points (SD 5.1 points) in the BA and control groups, respectively, a difference of -3.8 (95% confidence interval -6.9 to -0.6) after adjusting for baseline PHQ-9 score and centre, representing a reduction in depression in the BA arm. Therapy was delivered as intended. BA was acceptable to participants, carers and therapists. Value-of-information analysis indicates that the benefits of conducting a definitive trial would be likely to outweigh the costs. It is estimated that a sample size of between 580 and 623 participants would be needed for a definitive trial. Target recruitment was not achieved, although we identified methods to improve recruitment. The Behavioural Activation Therapy for Depression after Stroke trial was feasible with regard to the majority of outcomes. The outstanding issue is whether or not a sufficient number of participants could be recruited within a reasonable time frame for a definitive trial. Future work is required to identify whether or not there are sufficient sites that are able to deliver the services required for a definitive trial. Current Controlled Trials ISRCTN12715175. This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 47. See the NIHR Journals Library website for further project information.


Toward understanding cancer stem cell heterogeneity in the tumor microenvironment.
The epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) formation are two paramount processes driving tumor progression, therapy resistance, and cancer metastasis. Recent experiments show that cells with varying EMT and CSC phenotypes are spatially segregated in the primary tumor. The underlying mechanisms generating such spatiotemporal dynamics in the tumor microenvironment, however, remain largely unexplored. Here, we show through a mechanism-based dynamical model that the diffusion of EMT-inducing signals such as TGF-β, together with noncell autonomous control of EMT and CSC decision making via the Notch signaling pathway, can explain experimentally observed disparate localization of subsets of CSCs with varying EMT phenotypes in the tumor. Our simulations show that the more mesenchymal CSCs lie at the invasive edge, while the hybrid epithelial/mesenchymal (E/M) CSCs reside in the tumor interior. Further, motivated by the role of Notch-Jagged signaling in mediating EMT and stemness, we investigated the microenvironmental factors that promote Notch-Jagged signaling. We show that many inflammatory cytokines such as IL-6 that can promote Notch-Jagged signaling can (i) stabilize a hybrid E/M phenotype, (ii) increase the likelihood of spatial proximity of hybrid E/M cells, and (iii) expand the fraction of CSCs. To validate the predicted connection between Notch-Jagged signaling and stemness, we knocked down JAG1 in hybrid E/M SUM149 human breast cancer cells in vitro. JAG1 knockdown significantly restricted tumor organoid formation, confirming the key role that Notch-Jagged signaling can play in tumor progression. Together, our integrated computational-experimental framework reveals the underlying principles of spatiotemporal dynamics of EMT and CSCs.


Bcl-2 and Bax exert opposing effects on Ca2+ signaling, which do not depend on their putative pore-forming region.
Recent work has shown that Bcl-2 and other anti-apoptotic proteins partially deplete the endoplasmic reticulum (ER) Ca(2+) store and that this alteration of Ca(2+) signaling reduces cellular sensitivity to apoptotic stimuli. We expressed in HeLa cells Bcl-2, Bax, and Bcl-2/Bax chimeras in which the putative pore-forming domains of the two proteins (alpha 5-alpha 6) were mutually swapped, comparing the effects on Ca(2+) signaling of the two proteins and relating them to defined molecular domains. The results showed that only Bcl-2 reduces ER Ca(2+) levels and that this effect does not depend on the alpha 5-alpha 6 helices of this oncoprotein. Soon after its expression, Bax increased ER Ca(2+) loading, with ensuing potentiation of mitochondrial Ca(2+) responses. Then the cells progressed into an apoptotic phenotype (which included drastic reductions of cytosolic and mitochondrial Ca(2+) responses and alterations of organelle morphology). These results provide a coherent scenario that high-lights a primary role of Ca(2+) signals in deciphering apoptotic stimuli.


The heme groups of cytochrome o from Escherichia coli.
Cytochrome o, one of the two terminal ubiquinol oxidases of Escherichia coli, is structurally and functionally related to cytochrome c oxidase of mitochondria and some bacteria. It has two heme groups, one of which binds CO and forms a binuclear oxygen reaction center with copper. The other heme is unreactive toward ligands, exhibits strong interactions with the binuclear center, and is mainly responsible for the reduced-minus-oxidized alpha band. Protoheme has been thought to be the prosthetic group of b-type cytochromes, including cytochrome o. However, the hemes of cytochrome o are of a different kind, for which we propose the name heme O. Its pyridine hemochrome spectrum is blue-shifted by 4 nm relative to that of protoheme, and chromatographic behavior showed that it is much more hydrophobic than protoheme. Fast atom bombardment mass spectrometry yielded a molecular mass of 839 Da. Heme O is proposed to be a heme A-like molecule, containing a 17-carbon hydroxyethylfarnesyl side chain, but with a methyl residue replacing the formyl group.


Alpha1-adrenergic receptors prevent a maladaptive cardiac response to pressure overload.
An alpha1-adrenergic receptor (alpha1-AR) antagonist increased heart failure in the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), but it is unknown whether this adverse result was due to alpha1-AR inhibition or a nonspecific drug effect. We studied cardiac pressure overload in mice with double KO of the 2 main alpha1-AR subtypes in the heart, alpha 1A (Adra1a) and alpha 1B (Adra1b). At 2 weeks after transverse aortic constriction (TAC), KO mouse survival was only 60% of WT, and surviving KO mice had lower ejection fractions and larger end-diastolic volumes than WT mice. Mechanistically, final heart weight and myocyte cross-sectional area were the same after TAC in KO and WT mice. However, KO hearts after TAC had increased interstitial fibrosis, increased apoptosis, and failed induction of the fetal hypertrophic genes. Before TAC, isolated KO myocytes were more susceptible to apoptosis after oxidative and beta-AR stimulation, and beta-ARs were desensitized. Thus, alpha1-AR deletion worsens dilated cardiomyopathy after pressure overload, by multiple mechanisms, indicating that alpha1-signaling is required for cardiac adaptation. These results suggest that the adverse cardiac effects of alpha1-antagonists in clinical trials are due to loss of alpha1-signaling in myocytes, emphasizing concern about clinical use of alpha1-antagonists, and point to a revised perspective on sympathetic activation in heart failure.


Fast, high-resolution 3D dosimetry utilizing a novel optical-CT scanner incorporating tertiary telecentric collimation.
This study introduces a charge coupled device (CCD) area detector based optical-computed tomography (optical-CT) scanner for comprehensive verification of radiation dose distributions recorded in nonscattering radiochromic dosimeters. Defining characteristics include: (i) a very fast scanning time of approximately 5 min to acquire a complete three-dimensional (3D) dataset, (ii) improved image formation through the use of custom telecentric optics, which ensures accurate projection images and minimizes artifacts from scattered and stray-light sources, and (iii) high resolution (potentially 50 microm) isotropic 3D dose readout. The performance of the CCD scanner for 3D dose readout was evaluated by comparison with independent 3D readout from the single laser beam OCTOPUS-scanner for the same PRESAGE dosimeters. The OCTOPUS scanner was considered the "gold standard" technique in light of prior studies demonstrating its accuracy. Additional comparisons were made against calculated dose distributions from the ECLIPSE treatment-planning system. Dose readout for the following treatments were investigated: (i) a single rectangular beam irradiation to investigate small field and very steep dose gradient dosimetry away from edge effects, (ii) a 2-field open beam parallel-opposed irradiation to investigate dosimetry along steep dose gradients, and (iii) a 7-field intensity modulated radiation therapy (IMRT) irradiation to investigate dosimetry for complex treatment delivery involving modulation of fluence and for dosimetry along moderate dose gradients. Dose profiles, dose-difference plots, and gamma maps were employed to evaluate quantitative estimates of agreement between independently measured and calculated dose distributions. Results indicated that dose readout from the CCD scanner was in agreement with independent gold-standard readout from the OCTOPUS-scanner as well as the calculated ECLIPSE dose distribution for all treatments, except in regions within a few millimeters of the edge of the dosimeter, where edge artifact is predominant. Agreement of line profiles was observed, even along steep dose gradients. Dose difference plots indicated that the CCD scanner dose readout differed from the OCTOPUS scanner readout and ECLIPSE calculations by approximately 10% along steep dose gradients and by approximately 5% along moderate dose gradients. Gamma maps (3% dose-difference and 3 mm distance-to-agreement acceptance criteria) revealed agreement, except for regions within 5 mm of the edge of the dosimeter where the edge artifact occurs. In summary, the data demonstrate feasibility of using the fast, high-resolution CCD scanner for comprehensive 3D dosimetry in all applications, except where dose readout is required close to the edges of the dosimeter. Further work is ongoing to reduce this artifact.


Body size evolution in mammals: complexity in tempo and mode.
Body size correlates with virtually every aspect of species biology, so understanding the tempo and mode of its evolution is of key importance in macroecology and macroevolution. Here we use body mass data from 3,473 of 4,510 extant mammalian species and an almost complete species-level phylogeny to determine the best model of log(body mass) evolution across all mammals, split taxonomically and spatially. An early-burst model fits better across all mammals than do models based on either Brownian motion or an Ornstein-Uhlenbeck process, suggesting that mammals experienced a burst of morphological evolution relatively early in their history that was followed by slower change. We also use spatial models to investigate rates of body mass evolution within ecoregions. These models show that around 50% of the variation in rate can be explained by just a few predictors. High estimated rates are associated with cold, low-lying, species-poor, high-energy, mainland ecoregions. We conclude that the evolution of mammalian body size has been influenced by a complex interplay among geography, climate, and history.


Trends and determinants of tobacco use initiation in India: analysis of two rounds of the Global Adult Tobacco Survey.
Early initiation of tobacco use can lead to lifelong addiction and increases tobacco-attributable morbidity and mortality. This study assesses trends in tobacco use initiation and factors associated with tobacco use initiation using disaggregated data from two rounds of the Global Adult Tobacco Survey India (GATS; 2009-2010 (GATS 1) and 2016-2017 (GATS 2)). Secondary analysis of repeated cross-sectional studies. The study involved data from 69 296 individuals and 76 069 households in GATS 1 and 74 037 individuals and 77 170 households in GATS 2, two rounds of a nationally representative survey in India. Mean age of initiation (as recalled by the participants) of smoked and smokeless tobacco (SLT) use (dependent variable) was compared and analysed across different sociodemographic variables (independent factors). We assessed change in mean age of initiation of tobacco usage on a daily basis between GATS 1 and GATS 2, and investigated the factors associated with early tobacco use initiation in the GATS 2 dataset (reported using adjusted ORs (aORs) with 95% CIs). The mean age of initiation of smoked tobacco and SLT in GATS 2 was 20.9±8.5 and 22.3±10.6 years, compared with 18.5±9.7 and 19.7±12.0 years in GATS 1. The mean age of initiation increased with age and among those who were better aware of the adverse effects of tobacco. As per GATS 2, males initiated smoked tobacco and SLT use earlier (20.6±7.4 and 21.7±9.1) than females (23.3±14.2 and 23.2±12.6 years). Younger participants (15-24 years) reported earlier initiation of SLT (15.5±4.2 years) compared with others. Binary logistic regression depicted variables associated with early initiation of tobacco. Awareness about the harms caused by tobacco affected the odds of SLT (aOR 1.4, 95% CI 1.3 to 1.7) and dual usage initiation (1.8, 1.6 to 2.0), but not of initiation of smoked tobacco products (1.1, 0.9 to 1.2). More robust health advocacy campaigns that communicate the harmful effects of tobacco on health could be useful to delay tobacco initiation, along with reducing the ease of access and affordability of tobacco products among vulnerable groups.


Hepatitis C in hemodialysis patients.
Despite reduction of hepatitis C prevalence after recognition of the virus and testing of blood products, hemodialysis (HD) patients still comprise a high risk group. The natural history of hepatitis C virus (HCV) infection in dialysis is not fully understood while the clinical outcome differs from that of the general population. HD patients show a milder liver disease with lower aminotransferase and viral levels depicted by milder histological features on liver biopsy. Furthermore, the "silent" clinical course is consistent with a slower disease progression and a lower frequency of cirrhosis and hepatocellular carcinoma. Potential explanations for the "beneficial" impact of uremia and hemodialysis on chronic HCV infection are impaired immunosurveillance leading to a less aggressive host response to the virus and intradialytic release of "hepatoprotective" cytokines such as interferon (IFN)-α and hepatocyte growth factor. However, chronic hepatitis C is associated with a higher liver disease related cardiovascular and all-cause mortality of HD patients. Therapy is indicated in selected patients groups including younger patients with low comorbidity burden and especially renal transplant candidates, preferably after performance of a liver biopsy. According to current recommendations, choice of treatment is IFN or pegylated interferon with a reported sustained viral response at 30%-40% and a withdrawal rate ranging from 17% to 30%. New data regarding combination therapy with low doses of ribavirin which provide higher standard variable rates and good safety results, offer another therapeutic option. The new protease inhibitors may be the future for HCV infected HD patients, though data are still lacking.


On the presence of C2-ceramide in mammalian tissues: possible relationship to etherphospholipids and phosphorylation by ceramide kinase.
C(2)-ceramide (N-acetyl-sphingenine) is often used as an analog to study ceramide-mediated cellular processes. According to Lee et al. [J. Biol. Chem. 271 (1996), 209-217], C(2)-ceramide is formed by an acetyl transfer from platelet-activating factor (PAF, 1-O-alkyl-2-acetyl-sn-glycero-3-phosphocholine) to sphingenine. To substantiate these unconfirmed findings, we (i) developed a method to quantify C(2)-ceramide and (ii) analyzed C(2)-ceramide levels in Pex5(-/-) mice, a model for Zellweger syndrome, in which the synthesis of ether lipids such as PAF is impaired. The presence of C(2)-ceramide could be established in brain (+/-10 pmol/g) and liver (+/-25 pmol/g) from control mice, and was approximately 5000-fold less than the main long-chain ceramide species. In Pex5(-/-) mice, C(2)-ceramide levels did not differ significantly compared to control tissues. Given the presence of a ceramide kinase in mammals, phosphorylation of C(2)-ceramide by human ceramide kinase (HsCERK) was tested. C(2)-ceramide appears to be a good substrate when albumin is used as carrier. In CHO cells overexpressing HsCERK, phosphorylation of exogenously added C(2)-ceramide could also be demonstrated. Our data indicate that C(2)-ceramide is present in mammalian tissues and can be converted to C(2)-ceramide-1-phosphate, in addition to other documented metabolic alterations, but does not seem to be linked to ether lipid metabolism.


Effects of bis(guanylhydrazones) on the activity and expression of ornithine decarboxylase.
Derivatives of glyoxal bis(guanylhydrazone) (GBG), such as methylglyoxal bis(guanylhydrazone) and ethylglyoxal bis(guanylhydrazone), are potent inhibitors of S-adenosylmethionine decarboxylase (EC 188.8.131.52), the key enzyme required for the synthesis of spermidine and spermine. These compounds, but not the parent compound, induce a massive accumulation of putrescine, partly by blocking the conversion of putrescine into spermidine, but also by strikingly stimulating ornithine decarboxylase (ODC; EC 188.8.131.52) activity. The mechanism of the stimulation of ODC activity and enhanced accumulation of the enzyme protein apparently involved a distinct stabilization of the enzyme against intracellular degradation. However, although the parent compound GBG also stabilized ODC, it powerfully inhibited the enzyme activity and the accumulation of immunoreactive protein in cultured L1210 leukaemia cells. Kinetic considerations indicated that, in addition to the stabilization, all three compounds, GBG in particular, inhibited the expression of ODC. It is unlikely that the decreased rate of synthesis of ODC was attributable to almost unaltered amounts of mRNA in drug-treated cells, thus supporting the view that especially GBG apparently depressed the expression of ODC at some post-transcriptional level.


Pseudomonas lini sp. nov., a novel species from bulk and rhizospheric soils.
The taxonomic position of eight fluorescent Pseudomonas strains isolated from bulk and rhizospheric soils, and from water was examined. These eight strains clustered in one phenon together with Pseudomomas mandelii (CFBP 4844T), but could still be differentiated from this type strain by four phenotypic features. The eight stains exhibited internal DNA-DNA hybridization values ranging from 60 to 100%, with deltaTm below 5 degrees C (3.9 and 4.3 degrees C) for the lowest values (60 and 66%). The percentages of hybridization with type or reference strains of other Pseudomonas species tested ranged from 12 to 60% (deltaTm = 5.5 degrees C), indicating that the eight isolates studied constituted a discrete DNA homology group. Comparison of the 16S rDNA sequence of the strain representing this group (CFBP 5737T) with the sequences of other strains belonging to the genus Pseudomonas revealed that strain CFBP 5737T was a member of this genus and that these bacteria did not cluster with any previously described species of the genus Pseudomonas. The eight isolates belonged to two siderovars different from those described so far. On the basis of the results of phenotypic, DNA-DNA and phylogenetic analyses, and of siderotyping, a new species, Pseudomonas lini sp. nov. (type strain CFBP 5737T) is proposed.


Tuning jammed frictionless disk packings from isostatic to hyperstatic.
We perform extensive computational studies of two-dimensional static bidisperse disk packings using two distinct packing-generation protocols. The first involves thermally quenching equilibrated liquid configurations to zero temperature over a range of thermal quench rates r and initial packing fractions followed by compression and decompression in small steps to reach packing fractions φ(J) at jamming onset. For the second, we seed the system with initial configurations that promote micro- and macrophase-separated packings followed by compression and decompression to φ(J). Using these protocols, we generate more than 10(4) static packings over a wide range of packing fraction, contact number, and compositional and positional order. We find that disordered, isostatic packings exist over a finite range of packing fractions in the large-system limit. In agreement with previous calculations, the most dilute mechanically stable packings with φ min ≈ 0.84 are obtained for r > r*, where r* is the rate above which φ(J) is insensitive to rate. We further compare the structural and mechanical properties of isostatic versus hyperstatic packings. The structural characterizations include the contact number, several order parameters, and mixing ratios of the large and small particles. We find that the isostatic packings are positionally and compositionally disordered (with only small changes in a number of order parameters), whereas bond-orientational and compositional order increase strongly with contact number for hyperstatic packings. In addition, we calculate the static shear modulus and normal mode frequencies (in the harmonic approximation) of the static packings to understand the extent to which the mechanical properties of disordered, isostatic packings differ from partially ordered packings. We find that the mechanical properties of the packings change continuously as the contact number increases from isostatic to hyperstatic.


Comparison of cognitive functions between first-episode schizophrenia patients, their unaffected siblings and individuals at clinical high-risk for psychosis.
Cognitive impairment is a core feature of schizophrenia and has been observed in both familial (FHR) and clinical high-risk (CHR) samples. Nonetheless, there is a paucity of research directly contrasting cognitive profiles in these two high-risk states and first-episode schizophrenia. This study aimed to compare cognitive functions in patients with first-episode schizophrenia-spectrum disorder (FES), their unaffected siblings (FHR), CHR individuals and healthy controls. A standardized battery of cognitive assessments was administered to 69 FES patients, 71 help-seeking CHR individuals without family history of psychotic disorder, 50 FHR participants and 68 controls. FES and CHR participants were recruited from territory-wide early intervention service for psychosis in Hong Kong. CHR status was ascertained using Comprehensive Assessment of At-Risk Mental State. Among four groups, FES patients displayed the largest global cognitive impairment and had medium-to-large deficits across all cognitive tests relative to controls. CHR and FHR participants significantly underperformed in most cognitive tests than controls. Among various cognitive tests, digit symbol coding demonstrated the greatest magnitude of impairment in FES and CHR groups compared with controls. No significant difference between two high-risk groups was observed in global cognition and all individual cognitive tests except digit symbol coding which showed greater deficits in CHR than in FHR participants. Clinical and familial risk groups experienced largely comparable cognitive impairment that was intermediate between FES and controls. Digit symbol coding may have the greatest discriminant capacity in distinguishing FES and CHR from healthy controls, and between two high-risk samples.


Serum and cerebrospinal fluid cystatin C levels in vascular and Alzheimer's dementia.
Cystatin C, a cysteine protease inhibitor, has been implicated in the neurodegenerative and repair processes of the nervous system, and the deposition of the same protein together with beta amyloid peptide was found as cerebral amyloid angiopathy (CAA) in different types of dementias. Because of the differential diagnostic importance, serum and cerebrospinal fluid (CSF) cystatin C levels of 24 late onset Alzheimer's demented (AD) and 16 ischemic type of vascular demented (VD) probands were compared with 17 aged control (AC) persons. The serum and CSF cystatin levels were found in the normal range in all groups. The ischemic VD probands had the tendency to have higher cystatin C levels than the AD. No correlation has been found with the severity and duration of dementia and with the other measured parameters. These results indicate that lower than normal CSF cystatin C level is not a diagnostic marker in ischemic VD and CAA related to AD.


Measuring Vapor Intrusion: From Source Science Politics to a Transdisciplinary Approach.
Investigation of indoor air quality has been on the upswing in recent years. In this article, we focus on how the transport of subsurface vapors into indoor air spaces, a process known as "vapor intrusion," (VI) is defined and addressed. For environmental engineers and physical scientists who specialize in this emerging indoor environmental exposure science, VI is notoriously difficult to characterize, leading the regulatory community to seek improved science-based understandings of VI pathways and exposures. Yet despite the recent growth in VI science and competition between environmental consulting companies, VI studies have largely overlooked the social and political field in which VI problems emerge and are experienced by those at risk. To balance and inform current VI studies, this article explores VI science and policy and develops a critique of what we call "source science politics." Drawing inspiration from the creative synthesis of social and environmental science/engineering perspectives, the article offers a transdisciplinary approach to VI that highlights collaboration with social scientists and impacted communities and cultivates epistemic empathy.


Tick-borne encephalitis (TBE) vaccine to medically immunosuppressed patients with rheumatoid arthritis: A prospective, open-label, multi-centre study.
Tick-borne Encephalitis (TBE) is endemic in south-eastern Sweden as well as in the Baltic regions, Central Europe and Russia. Ageing and immunosuppressed individuals are more prone to severe disease and neurological complications. We assessed the immunogenicity of TBE-vaccine in rheumatoid arthritis (RA) patients treated with tumor necrosis factor-inhibitors (TNFi) and/or methotrexate (MTX). TBE vaccine, FSME-Immune(®) or Encepur(®), was administered to non-immune RA patients as well as age and gender matched healthy controls. Individuals <60 years of age were given three doses at month 0, 1, 12. Individuals ≥ 60 years old were given an additional priming dose at month 3, i.e. a total of four doses. Tick-borne encephalitis neutralizing antibodies were assessed by a rapid fluorescent focus inhibition test. The study population consisted of 66 patients and 56 age and gender matched healthy controls. Median age was 58.5 years. The patients were either treated with TNFi (n=16), TNFi+MTX (n=36) or MTX (n=14). After the last TBE-vaccine dose, given one year after the first, 39% of the patients compared to 79% of the healthy controls had seroprotective levels (p=<0.05). Standard TBE-vaccine schedule does not confer enough immunogenicity in this group of immunosuppressed patients, who should be carefully informed about a higher risk for vaccination failure and risk of infection when exposed in high-endemic areas.


[A new look at the nursing care provided in basic health units in Juiz de Fora-MG].
The purpose of this study is to analyze the current "praxis" regarding the nursing care provided in Basic Health Units. The reasons for developing this study are the evidence of a care based on healing actions and the importance of changing this model and redefining nursing care. This is a qualitative, descriptive and analytical study. The results revealed that the nursing care in the Basic Health Units changes according to its specificity and the subjectivity of the nurses who provide it. In sum, authors emphasize the importance of this professional as a member of the health team at the Basic Health Units in the city of Juiz de Fora, MG.


Expression of small heat-shock proteins at low temperatures. A possible role in protecting against chilling injuries.
We previously reported that short exposure of tomato (Lycopersicon esculentum L.) fruits to high temperature protects them from chilling injury. To study the involvement of heat-shock proteins (HSPs) in the acquisition of low-temperature tolerance, we cloned two heat-shock-induced genes that are also expressed at low temperatures. The cloned cDNAs belong to the small HSP group. Sequence analyses of the clones showed perfect homology to the tomato-ripening gene tom66 and to the tomato chloroplastic HSP21 gene tom111. The expression of both genes was induced by high temperature in fruits, flowers, leaves, and stems, but not by low or ambient temperatures or by other stresses such as drought and anaerobic conditions. When the heated fruits were transferred to low temperature, tom66 and tom111 mRNA levels first decreased but were then reinduced. Induction was not observed in nonheated fruits at low temperature. Immunodetection of tom111-encoded protein indicated that this protein is present at low temperatures in the heated fruits. The results of this study show that the expression of tom66 and tom111 is correlated with protection against some, but not all, symptoms of chilling injury.


Autoradiographic localization of muscarinic cholinergic receptors in rat brainstem.
We have localized muscarinic cholinergic receptors in the rat brainstem by a light microscopic autoradiographic method. Initially, we examined the kinetics and specificity of the binding of radiolabeled quinuclidinyl benzilate ([3H]QNB) in slide-mounted, frozen tissue sections to determine that we were labeling the muscarinic cholinergic receptors as they had been described previously in biochemical pharmacological studies. Subsequently, using optimal binding parameters to obtain high specific to nonspecific ratios, we labeled tissue sections and generated autoradiograms by the apposition of emulsion-coated coverslips. We found high concentrations of autoradiographic grains associated with many nuclei in the brainstem including the superior colliculus, nuclei of the lateral lemniscus, pontine nucleus, parabrachial nucleus, trigeminal nerve nucleus (V), the tegmental nuclei, nucleus of the facial nerve (VII), the locus coeruleus, the medial vestibular nucleus, cochlear nucleus, of the tractus solitarius, and nucleus of the hypoglossal nerve (XII). We conclude that muscarinic cholinergic effects of acetylcholine and important in the normal function of both the sensory and motor systems. We speculate on the possible mechanisms of action of certain cholinergic agents, such as the mechanism of anticholinergic compounds when used to treat motion sickness or anticholinesterase poisoning.


Cost and effectiveness of an eye care adherence program for Philadelphia children with significant visual impairment.
The follow-up rate among children with vision problems in the authors' outreach programs has been <5%. The authors therefore developed a social worker (SW) intervention, the Children's Eye Care Adherence Program (CECAP), for Philadelphia school children. The objective of this study was to measure CECAP's effectiveness and cost, as well as to identify barriers to care through a conceptual framework and geomapping software. A SW reviewed records to identify children needing follow-up and phoned families to identify and resolve barriers to eye care and scheduled appointments. Effectiveness was defined as the percent completing ≥ 1 follow-up visit within the physician-recommended time frame. Cost was measured for SW time (SW wage rates+benefits) and additional materials (forms, postage, phone charges). Barriers were organized into a conceptual framework depicting predisposing factors, system factors, and financial factors. Geomapping software was used to illustrate follow-up rates. In all, 120 patients required additional pediatric ophthalmic care; 71 patients were contacted and returned for care (59.2%); 49 patients were contacted but did not return (40.8%). SW time was 3h rs/patient for those who returned and 2 hrs/patient for those who did not return. Based on the CECAP program total cost ($14,249) and the reimbursement payment ($6265.66), the net cost of the CECAP program was $7983.59. Predisposing factors were the primary barrier theme for patients who did not follow up. CECAP significantly improved adherence to eye care but comes at an additional cost. Future efforts should focus on reducing operational efficiencies and targeting CECAP based on predictors of follow-up.


Barriers and enhancers to dietary behaviour change for Aboriginal people attending a diabetes cooking course.
Aboriginal people access diabetes and nutrition education less than non-Aboriginal people. Culturally appropriate, effective and accessible diabetes and nutrition education for Aboriginal people is urgently needed. A qualitative approach was used to explore the experiences of Aboriginal people who had attended cooking courses run at the Aboriginal Medical Service Western Sydney between 2002 and 2007. Data from 23 semi-structured interviews were analysed thematically. Despite reported improvements in nutrition knowledge and cooking skills, the ability of participants to implement desired dietary changes varied. A new health diagnosis, such as diabetes, pre-diabetes, heart disease or cancer and the desire of participants to influence their families to lead healthier, diabetes-free lives were strong motivators for dietary change. In contrast, lack of family support for dietary change and a sense of social isolation caused by dietary change strongly impeded some participants' attempts to improve their diets. Other significant barriers were poor oral health and depression, the higher cost of healthier food and generational food preferences. Aboriginal cooking course participants faced multiple barriers to dietary change - social, financial, medical and historical. The family was the most crucial determinant of participant ability to achieve sustained dietary change.


Use of substructure-specific carbohydrate binding modules to track changes in cellulose accessibility and surface morphology during the amorphogenesis step of enzymatic hydrolysis.
Cellulose amorphogenesis, described as the non-hydrolytic "opening up" or disruption of a cellulosic substrate, is becoming increasingly recognized as one of the key steps in the enzymatic deconstruction of cellulosic biomass when used as a feedstock for fuels and chemicals production. Although this process is thought to play a major role in facilitating hydrolysis, the lack of quantitative techniques capable of accurately describing the molecular-level changes occurring in the substrate during amorphogenesis has hindered our understanding of this process. In this work, techniques for measuring changes in cellulose accessibility are reviewed and a new quantitative assay method is described. Carbohydrate binding modules (CBMs) with specific affinities for crystalline (CBM2a) or amorphous (CBM44) cellulose were used to track specific changes in the surface morphology of cotton fibres during amorphogenesis. The extents of phosphoric acid-induced and Swollenin-induced changes to cellulose accessibility were successfully quantified using this technique. The adsorption of substructure-specific CBMs can be used to accurately quantify the extent of changes to cellulose accessibility induced by non-hydrolytic disruptive proteins. The technique provided a quick, accurate and quantitative measure of the accessibility of cellulosic substrates. Expanding the range of CBMs used for adsorption studies to include those specific for such compounds as xylan or mannan should also allow for the accurate quantitative tracking of the accessibility of these and other polymers within the lignocellulosic biomass matrix.


Digital chest imaging using a selenium detector. The impact of hard copy size on observer performance: a computed tomography-controlled study.
The authors compare radiologist detection performance under clinical conditions for assessment of the effect of size reduction on the diagnostic performance of digital chest images obtained with a selenium detector. Sixty-five patients were examined with the digital system. The images were acquired without an antiscatter grid. Sixty-five posteroanterior life-size images (35 x 43 cm) and sixty-five posteroanterior minified images (56% of life size) were analyzed by three observers for detection of pulmonary, mediastinal, and pleural pathology, using computed tomography as the reference standard. The diagnostic value of life-size and minified images for the detection of these chest abnormalities was analyzed with receiver operating characteristic (ROC) methods. For the detection of the various abnormalities by all radiologists, the areas under the ROC curves with life-size images versus minified images, respectively, were as follows: pulmonary opacities, 0.78 versus 0.78; interstitial disease, 0.74 versus 0.75; mediastinal disease, 0.70 versus 0.72; and pleural abnormalities 0.72 versus 0.67. There was no statistically significant difference between the radiologists' performance in detecting pulmonary, mediastinal, and pleural pathology with life-size versus that with minified (56% of life size) digital selenium chest radiography.


Therapeutic targeting in the estrogen receptor hormonal pathway.
Estrogens work along with genetic changes to promote the development and growth of breast cancers. Because estrogenic hormones act via the estrogen receptors (ERs), ER-alpha and ER-beta, and the ER is present in more than half of breast tumors, this receptor has been the most widely targeted protein in breast cancer therapy. The presence of the ER in breast tumors predicts improved disease-free survival and response to selective ER modulators (SERMs), such as tamoxifen, or other forms of endocrine therapy. Suppression of ER activity by SERMs has proven to be a great benefit in the treatment of breast cancers and also in the prevention of breast cancer in women at high risk for the disease. The Study of Tamoxifen and Raloxifene trial comparing tamoxifen versus raloxifene effectiveness in breast cancer prevention is currently under way. To understand the balance of beneficial and undesirable effects of SERMs and to optimize their effectiveness, current investigations seek to characterize the genes activated or suppressed by these agents. Elucidation of the gene networks and cell signaling pathways under estrogen and SERM regulation and a clearer definition of the respective roles of ER-alpha and ER-beta and their coregulators in the actions of selective ER ligands, should enable the identification of new gene targets for therapeutic intervention and the development of novel drugs for the optimal treatment and prevention of breast cancer.


Pharmacology and clinical potential of vortioxetine in the treatment of major depressive disorder.
VORTIOXETINE IS A NEW MULTIMODAL ACTION ANTIDEPRESSANT WITH TWO TYPES OF ACTION: serotonin transporter (SERT) blockade and a strong affinity for several serotoninergic receptors. It is an antagonist of the 5-HT3 and 5-HT7 receptors, a partial agonist of 5-HT1B, and an agonist of 5-HT1A. Its combined action on SERT and four subtypes of serotoninergic receptors increases the extracellular concentration of serotonin, dopamine, and noradrenaline. Twelve clinical trials have been carried out, nine of which had positive results versus placebo. When active comparators were included in the study design, no significant differences were found except in one study in which the efficacy of vortioxetine was superior to the comparator (agomelatine) in depression resistant to selective serotonin reuptake inhibitors (SSRI)/serotonin-norepinephrine reuptake inhibitors (SNRI) treatment. Tolerability studies indicate that the drug does not cause any important problems on blood tests, vital signs, or on electrocardiography. The lack of weight gain and induction of metabolic syndrome and the lack of significant changes in the QTc are especially important. The incidence rate of sexual dysfunction is low and similar to placebo in various trials. Similarly, cognitive function remains intact with vortioxetine.


Electron-positron outflow from black holes.
Cosmological gamma-ray bursts (GRBs) appear as the brightest transient phenomena in the Universe. The nature of their central engine is a missing link in the theory of fireballs to stellar mass progenitors, and may be associated with low mass black holes. In contact with an external magnetic field B, black hole spin produces a gravitational potential on the wave function of charged particles. We show that a rapidly rotating black hole of mass M produces outflow from initially electrostatic equilibrium with normalized isotropic emission approximately 10(48)(B/B(c))(2)(M/7M)(2)sin (2) theta erg/s, where B(c) = 4.4x10(13) G. The half-opening angle satisfies theta >or = square root[B(c)/3B]. The outflow proposed as input to GRB fireball models.


Base-catalyzed C-alkylation of potassium enolates with styrenes via a metal-ene reaction: a mechanistic study.
Base-catalyzed, C-alkylation of potassium (K) enolates with styrenes (CAKES) has recently emerged as a highly practical and convenient method for elaboration or synthesis of pharmaceutically-relevant cores. K enolate-type precursors such as alkyl-substituted heterocycles (pyridines, pyrazines and thiophenes), ketones, imines, nitriles and amides undergo C-alkylation reactions with styrene in the presence of KOtBu or KHMDS. Surprisingly, no studies have probed the reaction mechanism beyond the likely initial formation of a K enolate. Herein, a synergistic approach of computational (DFT), kinetic and deuterium labelling studies rationalizes various experimental observations and supports a metal-ene-type reaction for amide CAKES. Moreover, our approach explains experimental observations in other reported C-alkylation reactions of other enolate-type precursors, thus implicating a general mechanism for CAKES.


Rodent malaria parasites suffer from the presence of conspecific clones in three-clone Plasmodium chabaudi infections.
We studied infection dynamics of Plasmodium chabaudi in mice infected with 3 genetically distinct clones--1 less virulent than the other 2--either on their own or in mixtures. During the acute phase of infection, total numbers of asexual parasites in mixed-clone infections were equal to those produced by the 3 clones alone, suggesting strong in-host competition among clones. During the chronic phase of the infection, mixed-clone infections produced more asexual parasites than single-clone infections, suggesting lower levels of competition than during the acute phase, and indicating that a genetically diverse infection is harder to control by the host immune system. Transmission potential over the whole course of infection was lower from mixed-clone infections than from the average of the 3 single-clone infections. These results suggest that in-host competition reduces both growth rate and probability of transmission for individual parasite clones.


Effect of application variables on emissions and distribution of fumigants applied via subsurface drip irrigation.
Soil fumigation is useful for controlling soil-borne pests and diseases in high-cash-value crops. Fumigants are highly volatile, and approaches to reduce atmospheric emissions are required to protect human and environmental health. Application of fumigants through drip irrigation has been proposed as a means to decrease fumigant emissions, improve fumigant distribution in soil, and minimize worker exposure. These experiments were conducted to investigate the effect of the configuration of the drip system on the volatilization and distribution of the fumigants 1,3-dichloropropene (1,3-D), propargyl bromide (PrBr), and methyl isothiocyanate (MITC) in bedded systems. Results indicated that changing the drip emitter spacing and using multiple drip lines in each bed had little effect on the emissions and distribution of any fumigant. Increasing the depth of application from 15 to 30 cm reduced volatilization of MITC by approximately 20 to >90%; emissions were reduced due to a decrease in the flux from the bed top, and deeper injection did not change the amount of fumigant volatilized from the bed side slope and furrow. Increasing the application depth resulted in a slight decrease in the rate of fumigant dissipation in soil, indicating the potential for some improvement in pest-control efficacy with deeper application.


Polychlorinated biphenyls and non-Hodgkin lymphoma.
Several epidemiologic studies suggest that polychlorinated biphenyl (PCB) levels measured in peripheral blood or adipose tissue are related to increased risk of non-Hodgkin lymphoma (NHL) and, therefore, may be at least partially responsible for the rising incidence of NHL unrelated to HIV infection in recent decades. Case-control studies that measured PCBs in blood, adipose tissue, or household carpet dust, at the time of diagnosis, have observed elevated NHL risk associated with concentrations of either total PCBs or of specific congeners. Similar associations have been found in a number of prospective cohorts. These associations do not seem to be due to confounding by other organochlorines or by other known NHL risk factors. These results support evidence of PCB carcinogenicity from animal studies. However, interpretation of the epidemiologic evidence is limited by the wide range in measurement precision across congeners and by the moderate to high correlation among many congeners. Occupational cohort studies provide very limited support for a relationship between PCBs and NHL. In conclusion, there is mounting evidence of a relationship between certain PCBs and risk of NHL, but important questions remain, especially regarding the magnitude, timing, and causality of that relationship.


Towards simulations of long-term behavior of neural networks: Modeling synaptic plasticity of connections within and between human brain regions.
Simulations of neural networks can be used to study the direct effect of internal or external changes on brain dynamics. However, some changes are not immediate but occur on the timescale of weeks, months, or years. Examples include effects of strokes, surgical tissue removal, or traumatic brain injury but also gradual changes during brain development. Simulating network activity over a long time, even for a small number of nodes, is a computational challenge. Here, we model a coupled network of human brain regions with a modified Wilson-Cowan model representing dynamics for each region and with synaptic plasticity adjusting connection weights within and between regions. Using strategies ranging from different models for plasticity, vectorization and a different differential equation solver setup, we achieved one second runtime for one second biological time.


Purification of contaminated peptides and proteins on synthetic membrane surfaces for matrix-assisted laser desorption/ionization mass spectrometry.
Effective MALDI-TOF MS of salt-, detergent-, and glycerol-contaminated peptide and protein samples is accomplished by loading samples onto synthetic membranes, washing away contaminants, adding matrix, and desorbing samples directly from the membrane surface. The method easily removes contaminants which prevent effective MALDI of peptides and proteins from stainless steel surfaces, obviating the need for laborious further purification and associated sample losses. Polyethylene, polypropylene, C8, and C18 surfaces all proved effective at removing contaminants. Scanning electron microscope images of sample surfaces reveal that significantly smaller matrix crystals form on polyethylene and polypropylene surfaces than on stainless steel, C8, or C18 surfaces. Desorption from polyethylene and polypropylene surfaces generates consistently reproducible spectra with better mass resolution than observed for samples desorbed from stainless steel. Improved resolution, combined with reduced intensity of product ion spectra, indicate that peptide and protein molecular ions have less internal energy when desorbed from polyethylene and polypropylene surfaces than from stainless steel. MALDI of contaminated samples can be accomplished by straightforward, on-probe purification, resulting in higher resolution spectra than observed in samples desorbed from stainless steel.


Improvement of insulin response in the streptozotocin model of insulin-dependent diabetes mellitus. Insulin response with and without a long-acting insulin treatment.
Streptozotocin-induced diabetes mellitus (STZ-DM) in rats is a model of type 1 diabetes, which is commonly used to study diabetes, but differs from human diabetic pathophysiology in its insulin resistance. An STZ-DM rat can be administered five times the dose of insulin compared to that of a diabetic patient. Thus, attaining normoglycaemia in STZ-DM rats with insulin injections is complicated, and it involves an obvious risk of overdosing before getting a response. This study was designed to investigate whether suboptimal treatment with long-acting insulin restores insulin sensitivity in the STZ-DM rat, and thus an approach to more closely mimic the human condition. Male Sprague-Dawley rats were made diabetic by means of a single intravenous injection of STZ (55 mg/kg body weight (BW)), resulting in an increase in blood glucose (BG) from 6.5 ± 0.2 to 22.5 ± 1.0 mmol/l (P 0.05) within 24 h. After treating the STZ-DM rats with vehicle for 14 days, BG was 26.1 ± 1.1 mmol/l, and the response to a single injection of fast-acting insulin (Humalog, 5 IE/kg BW) was a 23% reduction in BG. Thereafter, the rats were treated daily with a suboptimal dose of long-acting insulin for a total of 7 days (Insulatard, 5 IE/kg per day), which resulted in a BG level of 19.4 ± 2.7. The response to fast-acting insulin after the suboptimal treatment was a 61% reduction in BG. Thereafter, the animals were vehicle-treated for another 7 days, which resulted in a response to fast-acting insulin similar to the initial values (-34%). Furthermore, the group treated with suboptimal doses of long-acting insulin had a longer duration of the reduction in BG (150 min, as opposed to 90 min in the vehicle-treated groups). We conclude that the development of a decreased insulin response occurs rapidly within the first 2 weeks after the onset of diabetes in STZ-DM rats. This leads to a brief and significantly reduced decrease in BG when fast-acting insulin is administered. The insulin response is increased by treatment with suboptimal doses of long-acting insulin, but rapidly decreases again when treatment is withdrawn. Regular administration of suboptimal insulin doses may provide an approach to eliminate the effects of a lowered insulin response.


A bivariate pseudolikelihood for incomplete longitudinal binary data with nonignorable nonmonotone missingness.
For analyzing longitudinal binary data with nonignorable and nonmonotone missing responses, a full likelihood method is complicated algebraically, and often requires intensive computation, especially when there are many follow-up times. As an alternative, a pseudolikelihood approach has been proposed in the literature under minimal parametric assumptions. This formulation only requires specification of the marginal distributions of the responses and missing data mechanism, and uses an independence working assumption. However, this estimator can be inefficient for estimating both time-varying and time-stationary effects under moderate to strong within-subject associations among repeated responses. In this article, we propose an alternative estimator, based on a bivariate pseudolikelihood, and demonstrate in simulations that the proposed method can be much more efficient than the previous pseudolikelihood obtained under the assumption of independence. We illustrate the method using longitudinal data on CD4 counts from two clinical trials of HIV-infected patients.


Characterization of myenteric interneurons with somatostatin immunoreactivity in the guinea-pig small intestine.
The projections, connections, morphology and electrophysiological features of the myenteric interneurons with somatostatin immunoreactivity in the guinea-pig small intestine have been established using retrograde tracing, immunohistochemistry, confocal microscopy and intracellular recording. After application of the fluorescent dye, 1,1'-didodecyl-3,3,3',3'-tetramethyl indocarbocyanine perchlorate (DiI), to the myenteric plexus, up to 900 nerve cell bodies were labelled in each preparation. Somatostatin-immunoreactive neurons accounted for 13% of all retrogradely labelled cells and were located up to 70 mm orally. When DiI was applied to the submucous ganglia, many myenteric neurons were labelled and 8% of all retrogradely labelled cells were somatostatin immunoreactive and were located up to 60 mm oral to the DiI application sites. These neurons had ovoid cell bodies, a single axon, several long filamentous dendrites and received close contacts from 40-200 somatostatin-immunoreactive varicosities. Intracellular recordings revealed that these cells had features of both S (i.e. with Synaptic inputs) and AH (i.e. neurons with After Hyperpolarization) cells, receiving fast excitatory synaptic inputs, having characteristic "sag" in their response to hyperpolarizing current pulses and sometimes a long afterhyperpolarization following soma action potentials. It is concluded that somatostatin-immunoreactive neurons have distinct electrophysiological features and form very long anally directed interneuronal chains that connect with both myenteric and submucous neurons.


Accelerated ageing of the lung in COPD: new concepts.
The rise in life expectancy worldwide has been accompanied by an increased incidence of age-related diseases, representing an enormous burden on healthcare services and society. All vital organs lose function with age, and this is well described in the lung, with a progressive decline in pulmonary function after the age of about 25 years. The lung ages, like any other organ, with progressive functional impairment and reduced capacity to respond to environmental stresses and injury. Normal physiological ageing results in enlarged alveolar spaces and loss of lung elasticity in the elderly known as 'senile emphysema', whereas in COPD there is destruction of the alveolar walls and fibrosis of peripheral airways. However, COPD shows striking age-associated features, such as an increase in cellular senescence, stem cell exhaustion, increased oxidative stress, alteration in the extracellular matrix and a reduction in endogenous antiageing molecules and protective pathways such as autophagy. In this review we discuss the evidence showing how oxidative stress induces accelerated ageing by upregulating the phosphatidylinositol-4,5-bisphosphate 3-kinase/AKT/mechanistic target of rapamycin signalling pathway resulting in depletion of stem cells, defective autophagy, reduced antioxidant responses and defective mitochondrial function thus generating further oxidative stress. Understanding the mechanisms of accelerated ageing in COPD may identify novel therapeutic approaches.


Development of a sensitive and fast UHPLC-MS/MS method for determination of clopidogrel, clopidogrel acid and clopidogrel active metabolite H4 in human plasma.
Quantitation of CAM H4 in biological matrix has been a challenge due to low concentrations, instability and the existence of four CAM diastereomers. Historically, either inactive clopidogrel acid or CAM diastereomers without separation were measured for exposure and PK parameters. This study presents a sensitive and fast UHPLC-MS/MS method for simultaneous quantitation of clopidogrel, clopidogrel acid and active metabolite H4 in human plasma. The method demonstrated the separation of H4 from other isomers and yet retained clopidogrel acid. Matrix stabilities, accuracy and precision, recovery and matrix effect were evaluated during development. With LLOQ of 0.05 ng/ml for clopidogrel and H4, and 5.5 min LC gradient, it is the most sensitive and fastest method to our knowledge.


Reactions of [14C]-3,4-dichloroisocoumarin with subunits of pituitary and spleen multicatalytic proteinase complexes (proteasomes).
Exposure to [14C]-3,4-dichloroisocoumarin (DCI) of multicatalytic proteinase complexes (MPC) isolated from bovine pituitary and spleen leads to label incorporation into several beta-type subunits, to rapid inactivation of the chymotrypsin-like (ChT-L) activity, and to a slower inactivation of other activities of the MPC. The pituitary and spleen MPCs differ in that the first contains almost exclusively the X, Y, and Z subunits, whereas in the latter these subunits are largely replaced by LMP2, LMP7, and MECL1. Preincubation with two peptidyl aledhyde inhibitors of the ChT-L activity protected the X subunit in the pituitary MPC and unexpectedly the LMP2 subunit in the spleen MPC from label incorporation, despite the greater amino acid sequence homology of the LMP7 subunit to that of the X subunit. Losses in the yield of amino acids in both subunits, shown by amino acid sequencing, and lability of the DCI-protein bond indicated formation of an acyl derivative by reaction of DCI with the threonine OH group. Brief exposure to [14C]-DCI led to preferential incorporation of label into the LMP2 and X subunits, consistent with the high inactivation rate constants of the ChT-L activity. Z-LLF-CHO, an inhibitor of ChT-L activity, but not Z-GPFL-CHO, an inhibitor of the branched chain amino acid preferring component, prevented incorporation of radioactivity into the X subunits, whereas both inhibitors prevented label incorporation into LMP2, indicating differences in susceptibility to inhibition between the two components. These and other data are consistent with involvement of the X and LMP2 subunits in expression of the ChT-L activity in the pituitary and spleen MPC, respectively, and suggest the catalytic functions of two other beta-subunits.


Comparative Descriptive Analysis of Physician Versus Patient-Directed Gabapentin Usage In Chronic Pain - A Preliminary Report.
Gabapentin is one of the most common medications employed in Pain Medicine, specifically targeting the management of neuropathic pain. We are most familiar with the incremental dosing strategy where a ceiling dose is eventually attained guided by efficacy and patient tolerance, after which a fixed dosing regimen is prescribed. We propose that autonomous short-term dose variations per patient could have rapid clinically significant effects in the management of chronic pain. This study examines the frequency at which patients take gabapentin on a fixed vs variable schedule and how the pattern of gabapentin use correlates with efficacy, side effects, and patient satisfaction. Single institution, cross-sectional observational survey study with data collection performed over 2 phases as a pilot for proof of concept. Remote contact via telephone with researchers calling from a quiet, private location within the hospital complex conducive for confidential conversation. Patients recently prescribed gabapentin were queried on the patterns of use and self-perceived efficacy, satisfaction, and side effects in accordance to a standardized oral script. Patients selected met the criteria of being new patients freshly prescribed gabapentin who have been consistently on the medication for at least a month, while having chronic pain symptoms for over 3 months. Responses were collected in the form of a 5-point Likert scale. Statistical analyses were performed using GraphPad Prism. Of the 222 patients, 92 patients agreed to participate in the survey for a response rate of 41.4. Of these, 51% had terminated the medication for various reasons. Of the patients still taking gabapentin, 73% were on a fixed schedule, while 27% were on a variable dosing schedule. Variable dosing cohort reported better efficacy (P = 0.027) and satisfaction (P = 0.036), while the side-effect profile between the 2 groups was similar. The study is limited by its nature of being a pilot, single-institution study performed on a relatively small sample size. None of the patients we surveyed had been given the autonomy to adjust gabapentin doses by their providers and this could significantly reduce the proportion of patients who would be encouraged to run a variable dosing regimen. This pilot study suggests that a significant portion of patients choose to administer variable doses of gabapentin and associate this with better efficacy and satisfaction. A larger study is needed to confirm this supposition. Based upon this pilot study, the variable dosing option may be an option for improved therapeutic efficacy or as an alternative to those whose lifestyles do not allow for fixed dosing regimens. Discussion of the risks of gabapentin, including respiratory depression, and clear dosage parameters of use, would need to be outlined when considering a variable dose regimen.


Midwives׳ clinical reasoning during second stage labour: Report on an interpretive study.
clinical reasoning was once thought to be the exclusive domain of medicine - setting it apart from 'non-scientific' occupations like midwifery. Poor assessment, clinical reasoning and decision-making skills are well known contributors to adverse outcomes in maternity care. Midwifery decision-making models share a common deficit: they are insufficiently detailed to guide reasoning processes for midwives in practice. For these reasons we wanted to explore if midwives actively engaged in clinical reasoning processes within their clinical practice and if so to what extent. The study was conducted using post structural, feminist methodology. to what extent do midwives engage in clinical reasoning processes when making decisions in the second stage labour? twenty-six practising midwives were interviewed. Feminist interpretive analysis was conducted by two researchers guided by the steps of a model of clinical reasoning process. Six narratives were excluded from analysis because they did not sufficiently address the research question. The midwives narratives were prepared via data reduction. A theoretically informed analysis and interpretation was conducted. using a feminist, interpretive approach we created a model of midwifery clinical reasoning grounded in the literature and consistent with the data. Thirteen of the 20 participant narratives demonstrate analytical clinical reasoning abilities but only nine completed the process and implemented the decision. Seven midwives used non-analytical decision-making without adequately checking against assessment data. over half of the participants demonstrated the ability to use clinical reasoning skills. Less than half of the midwives demonstrated clinical reasoning as their way of making decisions. The new model of Midwifery Clinical Reasoning includes 'intuition' as a valued way of knowing. Using intuition, however, should not replace clinical reasoning which promotes through decision-making can be made transparent and be consensually validated.


Biochemical aspirin resistance in stroke patients - a cross-sectional single centre study.
Aspirin use is known to reduce the recurrence of stroke. However, the clinical response to aspirin has been mixed. The rate of stroke recurrence whilst on aspirin treatment is still unacceptably high. A plausible explanation for this may be resistance to the effects of aspirin. The causes of aspirin resistance are manifold and multi-factorial. We conducted a study to investigate the prevalence rate of biochemical aspirin resistance in a cohort of aspirin-naïve stroke patients. We also sought to determine the inherent factors that may predispose towards the development of aspirin resistance. This was a cross-sectional, observational study conducted on patients admitted to our centre with an acute stroke who were aspirin-naïve. The diagnosis of an acute stroke was confirmed by clinical history and brain imaging. Fifty consecutive patients were prospectively enrolled. Socio-demographic data were collected and baseline blood investigations were performed. Patients were tested for biochemical aspirin resistance using Multiplate platelet analyser (Dynabyte, Munich, Germany) after 5 doses of aspirin, corresponding to a total dose of 900 mg. The median age of patients was 65.5 years and 54 % of patients were female. There were 11 smokers; of these 10 were male. Twenty-six (52 %) patients were Chinese, 21 (41 %) were Malay and 3 (6.0 %) were Indian. Aspirin resistance was present in 14 % of our patients. There was an inverse relationship between the presence of aspirin resistance and plasma HDL levels (r = -0.394; p = 0.005). There was no relationship observed between aspirin resistance and total cholesterol, triglycerides, LDL, HbA1c, ALT, ALP, urea and creatinine levels. There were no significant differences in demographic profiles or smoking status between the aspirin resistant and non-aspirin resistant groups. We did not find any link between ethnicity and aspirin resistance. Our results indicate that a lower HDL level is associated with biochemical aspirin resistance. This may increase platelet aggregation and consequently increase the risk of a recurrent stroke. The clinical implications for aspirin resistance are far reaching. Any evidence that correctable factors may negatively influence the action of aspirin warrants further investigation. The prevalence rate of biochemical aspirin resistance in our study is comparable to the findings in other studies performed in an Asian population. Further research is required to determine how our findings translate into clinical aspirin resistance and stroke recurrence.


[Pseudomembranous colitis: clinical, endoscopic and radiological correlation--a 2-year experience].
The incidence rates of pseudomembranous colitis are rising. Early diagnosis and treatment are required for management of this potentially life-threatening disease. This report outlines our 2-year experience (1997-1998) at the gastrointestinal institute with 43 patients diagnosed with pseudomembranous colitis and describes the clinical course and imaging studies. The group consisted of 25 women and 18 men, aged 34-93 years (mean: 67). Thirty-nine patients were treated with antibiotics. Twelve patients were referred directly to an endoscopic examination with a presumed clinical diagnosis of pseudomembranous colitis (diarrhea, fever and abdominal pain) that was confirmed by colonoscopy. Thirty-one were referred to colonoscopy following abdominal imaging performed to clarify cause of fever and abdominal pain. Twenty-nine patients had an abdominal CT, one had an US and one a barium follow-through. The CT finding suggesting pseudomembranous colitis included colonic mural thickening in 28 patients (71% diffuse versus 29% segmental colitis), with an average wall thickness of 16 mm. Sixteen patients (59%) had pericolonic fat changes and 15 patients (51%) had ascites. All of these patients, except one, had endoscopic findings consistent with pseudomembranous colitis. Five patients (11.6%) died due to the severe PMC. To conclude, as an abdominal CT is often performed in the acutely ill patient, it may arouse the diagnosis of pseudomembranous colitis in the proper clinical setting. Such a suspected diagnosis justifies endoscopic evaluation, which is the most reliable diagnostic examination.


Study of substrata of a slope susceptible to landslide in hilly environment using a geophysical method in the Nilgiris, India.
Landslides are one of the prevailing threats to life that cause huge loss to the environment. Around 3.7 million km2 of the area is exposed to landslides globally, and 820,000 km2 is at high risk for landslides in India. Rainfall and earthquakes are the two primary landslide-causing variables in India. The Nilgiris district which is in the south-western part of India is more prone to rainfall-induced landslides. This study intends to calculate the depth of the slip surface on a slope (Lovedale area, the Nilgiris) in the event of a future landslide using Multichannel Analysis of Surface Waves (MASW) and validate using bore log data. During November 2009 rainfall, a shallow landslide occurred at the toe of this slope. There is a greater chance that a landslide will occur again in the event of rainfall in the future. To comprehend how the sub-strata vary, and to forecast the depth of a prospective failure surface, the shear wave velocity (Vs) obtained from MASW proved beneficial. Slip surfaces, one at a shallow depth and another at a deeper depth, were found based on the shear wave velocity and bore log data. The importance of the MASW output in the engineering properties of soil was also studied. The compressional velocity (Vp) and shear wave velocity obtained from MASW were evaluated for their applicability in calculating the elastic moduli of soil. It was established that shear wave velocity was of greater significance than compressional velocity. The MASW results can be further used as a preliminary data for analysing the stability of the slope, reactivation of landslides, and landslide early warning system.


Sequence analysis of a cryptic plasmid pCJ419 from Campylobacter jejuni and construction of an Escherichia coli-Campylobacter shuttle vector.
A small cryptic plasmid, pCJ419, was identified in a human clinical isolate of Campylobacter jejuni, cloned and sequenced. pCJ419 is a circular molecule of 4013 bp with a G+C content of 27.1%. The products of four open reading frames (ORFs) share significant sequence similarity with putative proteins from known C. jejuni and Campylobacter coli plasmids. ORF-1 encodes a putative mobilisation protein (Mob). ORF-2 and ORF-3 encode proteins that have high identity to putative RepA and RepB proteins, respectively, of known C. jejuni and C. coli plasmids. ORF-4 encodes a protein that has high identity to a hypothetical protein of unknown function, Cjp32, previously described in a pVir plasmid of C. jejuni. Tandem repeating 22-bp sequences typical of a plasmid replication origin (ori) were identified upstream of the DNA sequences encoding putative replication initiation proteins. An Escherichia coli-Campylobacter shuttle cloning vector, pGU0202, was constructed using plasmid pMW2 that harbours a Campylobacter-derived kanamycin resistance gene [aph(3')-III]. The sequences encoding pCJ419 mob, RepA and RepB proteins were inserted upstream of aph(3')-III resulting in a stable construct of 6174 bp that was used to transform both E. coli and Campylobacter.


Sarcoidosis and lymphoma: a comparative study.
To assess the clinical features and outcome of lymphoma when associated with sarcoidosis and to determine whether this association gives lymphoma a better prognosis. Multicentre retrospective cohort study. Retrospective chart review. Twenty-one patients were included (9 males, 12 females). Median age at sarcoidosis diagnosis was 48 years (range: 24-68 years). In 14 cases, lymphoma occurred within a previously known sarcoidosis. Five patients received a concomitant diagnosis of sarcoidosis and lymphoma, whereas lymphoma preceded sarcoidosis in two patients. Three patients were diagnosed with Hodgkin's lymphoma and 18 patients with non-Hodgkin's lymphoma (diffuse large B-cell lymphoma (DLBCL) (n = 11), follicular lymphoma (n = 2), chronic lymphocytic leukemia/small lymphocytic lymphoma (n = 2), anaplastic large cell lymphoma ALK + (n = 1), angioimmunoblastic T-cell lymphoma (n = 1) and T-cell prolymphocytic leukemia (n = 1)). Thirteen patients were alive and in complete remission. Median age at the time of diagnosis of sarcoidosis was lower in patients with concomitant lymphoma compared with patients with sarcoidosis preceding lymphoma (34 years vs. 51 years, P = 0.01). Patients presenting with DLBCL associated with sarcoidosis were compared with DLBCL without sarcoidosis. No statistical difference was found in the risk of death or progression between the two groups (P = 0.685). We report here the largest series of lymphoma associated sarcoidosis patients. As opposed to previous studies, we observed a predominance of patients with DLBCL. Our study confirms the concept of the sarcoidosis-lymphoma syndrome. Large B-cell lymphoma does not have a better prognosis when associated with sarcoidosis.


Individualized Scan Protocols in Abdominal Computed Tomography: Radiation Versus Contrast Media Dose Optimization.
In contrast-enhanced abdominal computed tomography (CT), radiation and contrast media (CM) injection protocols are closely linked to each other, and therefore a combination is the basis for achieving optimal image quality. However, most studies focus on optimizing one or the other parameter separately. Reducing radiation dose may be most important for a young patient or a population in need of repetitive scanning, whereas CM reduction might be key in a population with insufficient renal function. The recently introduced technical solution, in the form of an automated tube voltage selection (ATVS) slider, might be helpful in this respect. The aim of the current study was to systematically evaluate feasibility of optimizing either radiation or CM dose in abdominal imaging compared with a combined approach. Six Göttingen minipigs (mean weight, 38.9 ± 4.8 kg) were scanned on a third-generation dual-source CT. Automated tube voltage selection and automated tube current modulation techniques were used, with quality reference values of 120 kVref and 210 mAsref. Automated tube voltage selection was set at 90 kV semimode. Three different abdominal scan and CM protocols were compared intraindividually: (1) the standard "combined" protocol, with the ATVS slider position set at 7 and a body weight-adapted CM injection protocol of 350 mg I/kg body weight, iodine delivery rate (IDR) of 1.1 g I/s; (2) the CM dose-saving protocol, with the ATVS slider set at 3 and CM dose lowered to 294 mg I/kg, resulting in a lower IDR of 0.9 g I/s; (3) the radiation dose-saving protocol, with the ATVS slider position set at 11 and a CM dose of 441 mg I/kg and an IDR 1.3 g I/s, respectively. Scans were performed with each protocol in arterial, portal venous, and delayed phase. Objective image quality was evaluated by measuring the attenuation in Hounsfield units, signal-to-noise ratio, and contrast-to-noise ratio of the liver parenchyma. The overall image quality, contrast quality, noise, and lesion detection capability were rated on a 5-point Likert scale (1 = excellent, 5 = very poor). Protocols were compared for objective image quality parameters using 1-way analysis of variance and for subjective image quality parameters using Friedman test. The mean radiation doses were 5.2 ± 1.7 mGy for the standard protocol, 7.1 ± 2.0 mGy for the CM dose-saving protocol, and 3.8 ± 0.4 mGy for the radiation dose-saving protocol. The mean total iodine load in these groups was 13.7 ± 1.7, 11.4 ± 1.4, and 17.2 ± 2.1 g, respectively. No significant differences in subjective overall image or contrast quality were found. Signal-to-noise ratio and contrast-to-noise ratio were not significantly different between protocols in any scan phase. Significantly more noise was seen when using the radiation dose-saving protocol (P < 0.01). In portal venous and delayed phases, the mean attenuation of the liver parenchyma significantly differed between protocols (P < 0.001). Lesion detection was significantly better in portal venous phase using the CM dose-saving protocol compared with the radiation dose-saving protocol (P = 0.037). In this experimental setup, optimizing either radiation (-26%) or CM dose (-16%) is feasible in abdominal CT imaging. Individualizing either radiation or CM dose leads to comparable objective and subjective image quality. Personalized abdominal CT examination protocols can thus be tailored to individual risk assessment and might offer additional degrees of freedom.


Effect of oxytetracycline administration on intestinal metabolism of oestrogens and on plasma sex hormones in healthy men.
The effect of oxytetracycline (1 g/day for five days) on the enterohepatic recycling of oestrogens and on plasma sex hormone concentrations was assessed in healthy men. Plasma oestrone (E1), oestradiol-17 beta (E2), 4-androstenedione (A), 5 alpha-dihydrotestosterone (5 alpha-DHT), total and free testosterone (T and free T), binding capacity of sex hormone binding globulin, luteinizing hormone, dehydroepiandrosterone-sulphate, urinary total E1, E2, and oestriol (E3), and oestriol-3-glucuronide (E3-3G) and faecal unconjugated and conjugated E1, E2, and E3 were measured by radioimmunoassay (RIA). Treatment with the antibiotic significantly increased the excretion of faecal conjugated oestrogens, which parallelled a decrease in urinary oestrogen excretion, especially of E3. The effect on urinary E3 could be explained almost entirely by the simultaneous decrease of urinary E3-3G concentrations. In urine and faeces the E2/E3 and E1 + E2/E3 ratios increased, probably because of the diminished reductive metabolism of oestrogens in the gut. No significant effects on plasma unconjugated oestrogen concentrations were observed. Moreover, in the present study oxytetracycline had no remarkable effect on plasma total, or free T concentrations, nor on other plasma hormones measured. Our results suggest that enterohepatic recycling and intestinal metabolism of oestrogens may be significant in men. The mechanism of action of antibiotics on oestrogen metabolism probably involves decreased hydrolysis by beta-glucuronidase of oestrogen conjugates by the intestinal contents, diminishing the reabsorption of aglycones of oestrogen conjugates and resulting in faecal loss of the steroids.


Evaluation of direct pharmacist intervention on conversion from parenteral to oral histamine H2-receptor antagonist therapy.
A program in which pharmacists were authorized to change parenteral histamine H2-receptor antagonist (H2RA) therapy to the oral route without first contacting the prescriber was evaluated on cost and appropriateness of use of the parenteral route. Parenteral therapy was received by 264 and 244 patients in the study and comparison groups, respectively. Length of parenteral H2RA therapy was less in the study group (4.8 vs. 7.5 d) as was length of total (parenteral + oral) therapy (8.4 vs. 12.1 d). Parenteral H2RA drug acquisition savings were $6225 in the six-week study period or $53,950 when annualized. Decreased oral therapy contributed additional savings. There was a significant decrease in the number of inappropriate parenteral doses of ranitidine per patient, the drug used in more than 80 percent of the patients. In addition to the direct effect of pharmacists' interventions, there appeared to be an indirect effect of the program, as physicians initiated route of administration changes on their own.


Proteus mirabilis chromosome mobilization by plasmid D: a physical characterization.
Plasmid D, a hybrid of plasmids P-lac and R1 drd19, mediates polarized chromosome mobilization from one origin in Proteus mirabilis strain PM5006, while the parental plasmids neither individually nor combined mobilize this chromosome. To elucidate its acquired mobilizing ability plasmid D was characterized physically in relation to P-lac and R1 drd19. Restriction patterns of these plasmids were compared and it was shown that D consists of P-lac and only the r-determinant (r-det) of R1 drd19. A mechanism for the formation of plasmid D, via transduction of the r-det and subsequent transposon-like integration into P-lac, involving insertion sequence IS1, was suggested. Evidence for aberration in plasmid D DNA as a result of r-det integration into P-lac was attributed to IS1 elements which flank the r-det. Recombination regions of parental plasmid DNA were located on HindIII fragments alpha and beta of plasmid D and were subsequently inserted in vitro into IncP-1 plasmid RP4 that fails to mobilize the P. mirabilis chromosome. RP4::HindIII alpha plasmids did not mobilize the latter chromosome, but rendered the Proteus host lac+. RP4::HindIII beta plasmids pMC1 and pMC17, containing the fragment in opposite orientations, mobilized the P. mirabilis chromsome. For pMC17, mobilization was indistinguishable from that of plasmid D, i.e. having the same orientation and the same single origin. However, mobilization promoted by pMC1 was from two distinctly different origins, different from that of pMC17. This apparently deviates from known examples where inversion of homologous DNA inserted into plasmids leads to mobilization from the same origin but in reverse direction.


[Kinetics of the cell population of transplantable murine B-16 melanoma after administration of mercaptoundecahydrododecaborate enriched with 10B].
The kinetics of DNA-synthesizing cells and melanocytes in the peripheral and central zones of transplantable B-16 mouse melanoma was studied by the cytometry and autoradiography methods at varying time after single administration of mercaptoundecahydrododecaborate saturated by 10B, a drug used for neutron capture therapy of malignant tumors. The drug was shown to induce proliferation and differentiation on the 1st day after injection (on the 8th day after transplantation). In the next 2 days proliferation did not change and differentiation was inhibited. The stimulation of proliferation and differentiation was more noticeable on tumor periphery, differentiation inhibition in tumor center.


HIV and hepatitis C virus infection in the United States: whom and how to test.
In the United States, of the 1.1 million persons infected with human immunodeficiency virus (HIV) and the 2.7 million infected with hepatitis C virus (HCV), approximately 16% and 50%, respectively, are unaware of their infection. Highly effective treatments have turned both diseases into manageable conditions, and in the case of hepatitis C, a disease that can be cured. Early diagnosis is imperative so that infected persons can take measures to stay healthy, get into care, benefit from therapy, and reduce the risk of transmission. In this report, we review current recommendations provided by the Centers for Disease Control and Prevention (CDC) and the United States Preventive Services Task Force on whom to screen for HIV and HCV infections, and recommendations from the CDC, the Association of Public Health Laboratories, and the Clinical and Laboratory Standards Institute on how to test for these infections.


Effect of Fusion Manner of Concave Molecules on the Properties of Resulting Nanoboats.
A boat-shaped compound, which can be viewed as the fusion of two concave molecules with crossed quinacridone and indolocarbazole throughout, was synthesized and characterized. The investigation determined that the fusion manner of two concave molecules has little influence on the molecular curvature and aromaticity when compared with its congener containing crossed indolocarbazole throughout. The situation of carbonyl groups is critical in adjusting the electronic structure and physicochemical properties due to the fixed position of nitrogen atoms.


Relationship of aluminum to Alzheimer's disease.
Alzheimer's disease is a progressive degenerative brain disease of unknown etiology, characterized by the development of large numbers of neurofibrillary tangles and senile plaques in the brain. Aluminum salts may be used experimentally to produce lesions which are similar, but not identical, to the neurofibrillary tangle. Although some studies have reported increased amounts of aluminum in the brains of Alzheimer's disease victims, these bulk analysis studies have been difficult to replicate and remain controversial. Using scanning electron microscopy with X-ray spectrometry, we have investigated this question on the cellular level. We have identified abnormal accumulations of aluminum within neurons derived from Alzheimer's disease patients containing neurofibrillary tangles. Similar accumulations have been detected in the numerous neurofibrillary tangle-bearing neurons seen in the brains of the indigenous native population of the island of Guam who suffer from amyotrophic lateral sclerosis and parkinsonism with dementia. Epidemiologic evidence strongly suggests a causal role for local environmental conditions relating to availability of aluminum, calcium, and magnesium. In view of the fact that a major consequence of acid rain is the liberation of large amounts of aluminum in bioavailable forms, concerns are raised about possible human health risks of this environmental phenomenon.


LC/MS study of the UV filter hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]-benzoate (DHHB) aquatic chlorination with sodium hypochlorite.
The fate of modern personal care products in the environment is becoming a matter of increasing concern because of the growing production and assortment of these compounds. More and more chemicals of this class are treated as emerging contaminants. Transformation of commercially available products in the environment may result in the formation of a wide array of their metabolites. Personal care products in swimming pools and in drinking water reservoirs may undergo oxidation or chlorination. There is much data on the formation of more toxic metabolites from original low toxicity commercial products. Therefore, reliable identification of all possible transformation products and a thorough study of their physicochemical and biological properties are of high priority. The present study deals with the identification of the products of the aquatic chlorination of the hexyl 2-[4-(diethylamino)-2-hydroxybenzoyl]-benzoate ultraviolet filter. High-performance liquid chromatography/mass spectrometry (HPLC/MS) and HPLC/MS/MS with accurate mass measurements were used for this purpose. As a result, three chlorinated transformation products were identified.


Enhancing the provider/patient relationship: the case for patient advocacy programs.
Given the highly personalized and individualistic nature of the health care experience, care and attention must be directed to meeting the needs of the patient faithfully--through both competent medical care and the more abstract, but no less important, intangible service needs. The authors describe one process for providing an enhanced level of service: the adoption and implementation of a patient advocacy program.