The computational structure of spike trains.
Neurons perform computations, and convey the results of those computations through the statistical structure of their output spike trains. Here we present a practical method, grounded in the information-theoretic analysis of prediction, for inferring a minimal representation of that structure and for characterizing its complexity. Starting from spike trains, our approach finds their causal state models (CSMs), the minimal hidden Markov models or stochastic automata capable of generating statistically identical time series. We then use these CSMs to objectively quantify both the generalizable structure and the idiosyncratic randomness of the spike train. Specifically, we show that the expected algorithmic information content (the information needed to describe the spike train exactly) can be split into three parts describing (1) the time-invariant structure (complexity) of the minimal spike-generating process, which describes the spike train statistically; (2) the randomness (internal entropy rate) of the minimal spike-generating process; and (3) a residual pure noise term not described by the minimal spike-generating process. We use CSMs to approximate each of these quantities. The CSMs are inferred nonparametrically from the data, making only mild regularity assumptions, via the causal state splitting reconstruction algorithm. The methods presented here complement more traditional spike train analyses by describing not only spiking probability and spike train entropy, but also the complexity of a spike train's structure. We demonstrate our approach using both simulated spike trains and experimental data recorded in rat barrel cortex during vibrissa stimulation.


Depression in Collegiate Runners and Soccer Players: Relationships with Serum 25-Hydroxyvitamin D, Ferritin, and Fractures.
The main purpose of this study was to evaluate relationships between depression versus serum 25-hydroxyvitamin D (vitamin D), serum ferritin (ferritin), and fractures across a competitive season. The authors conducted a prospective observational study (both pre- and post-season testing) on 51 collegiate soccer and cross-country athletes from a Midwest University. Our main outcome measure was depression, measured using the Center for Epidemiological Studies Depression Scale (CES-D). A CES-D score ≥ 16 represented the threshold value for clinical depression. Secondary outcome variables included vitamin D, ferritin, and fractures. Two athletes (3.9%; one female) pre-season while seven athletes (13.7%; five females) post-season demonstrated clinically relevant depression (CES-D score ≥ 16). Depression scores increased from pre- to post-season (6.0 to 8.9; p = 0.009; effect size = 0.53; n = 51). A medium effect noted for depressed athletes vs. non-depressed athletes (n = 7; post-season) to have lower pre-season serum vitamin D (38.4 vs. 50.2 ng/ml; p = 0.15; effect size = 0.68) with a small overall correlation effect (r = -0.08; p = 0.58). A medium correlation effect was noted between post-season ferritin vs. depression scores (r = -0.45; p = 0.01) in the female cohort only. Six athletes (11.8%) sustained fractures and had lower depression scores vs. non-injured athletes (4 vs. 10; p = 0.04; effect size = 1.08) post-season. Depression scores increased over a competitive season, especially in females. Small correlation effects were observed between depression and vitamin D. A medium correlation effect was noted between depression and low ferritin levels, in female athletes only. A large effect was noted between athletes sustaining fractures during the season and depression, post-season, with injured athletes being less depressed than non-injured athletes.


Evaluation, optimization, and application of three independent suspect screening workflows for the characterization of PFASs in water.
Suspect screening is a valuable tool for characterizing per- and polyfluoroalkyl substances (PFASs) in environmental media. Although a variety of data mining tools have been developed and applied for suspect screening of PFAS, few suspect screening workflows have undergone a comprehensive performance evaluation or optimization. The goals of this research were to: (1) evaluate and optimize three independent suspect screening workflows for the detection of PFASs in water samples; and (2) apply the optimized suspect screening workflows to an environmental sample to determine the extent to which suspect screening results converge. We evaluated and optimized suspect screening workflows using Compound Discoverer v3.2, enviMass v4.2, and FluoroMatch v2.4 using test samples containing 33 target PFASs. The average sensitivity (Sen) and selectivity (Sel) for each workflow across the test samples was: Compound Discoverer Sen = 71%, Sel = 85%; enviMass Sen = 89%, Sel = 80%; FluoroMatch Sen = 51%, Sel = 82%. We then applied the optimized workflows to a contaminated groundwater sample containing an unknown number of PFASs. Each workflow managed to annotate unique PFASs that were not annotated by the other workflows including 2 by Compound Discoverer and 19 each by enviMass and FluoroMatch. Thirty-two enviMass hits and 28 of the Compound Discoverer and FluoroMatch hits were annotated by at least one of the other workflows. Sixteen PFASs were annotated by all three of the optimized workflows. This work provides a basis for conducting suspect screening for PFASs that will lead to more consistent reporting of suspect screening data.


Two-center interference during the high harmonic generation in aligned O2 molecules.
We experimentally investigate the angular distribution and the laser intensity dependence of the two-center interference in high-order harmonic generation (HHG) from O2 molecules by comparing with CO2 molecules. Through the measurement of both the temporal evolution and the angular distribution of HHG, the characteristic enhancement and suppression are observed, which can be well explained by the modified interference model. Furthermore, we demonstrate that the spectral region of the constructive enhancement in aligned O2 molecules can be shifted by tuning the driving laser intensity.


Clinical presentation, auscultation recordings, ultrasonographic findings and treatment response of 12 adult cattle with chronic suppurative pneumonia: case study.
Auscultation is considered the critical component of the veterinary clinical examination for the diagnosis of bovine respiratory disease but the accuracy with which adventitious sounds reflect underlying lung pathology remains largely unproven. Modern portable ultrasound machines provide the veterinary practitioner with an inexpensive, non-invasive tool with which to examine the pleural surfaces and superficial lung parenchyma. Simultaneous recording of sounds overlying normal lung and defined pathology allows critical assessment of auscultated sounds in the same animal removing confounding factors such as respiratory rate and thickness of the chest wall (body condition). Twelve cows, referred to the University of Edinburgh Veterinary School, were diagnosed with chronic suppurative pneumonia and enrolled into this prospective study to record and monitor lung sounds, ultrasonographic findings, and response to a standardised antibiotic treatment regimen.Most cows (8/12) had a normal rectal temperature on presentation but all cows had received antibiotic therapy at some time in the previous two weeks and six animals were receiving antibiotic treatment upon admission. All cattle were tachypnoeic (>40 breaths per minute) with frequent and productive coughing, halitosis, and a purulent nasal discharge most noticeable when the head was lowered. Ultrasonographic examination of the chest readily identified pathological changes consistent with severe lung pathology subsequently confirmed as chronic suppurative pneumonia in four cows at necropsy; eight cows recovered well after antibiotic treatment and were discharged two to six weeks after admission. It proved difficult to differentiate increased audibility of normal lung sounds due to tachypnoea from wheezes; coarse crackles were not commonly heard. In general, sounds were reduced in volume over consolidated lung relative to normal lung tissue situated dorsally. Rumen contraction sounds were commonly transmitted over areas of lung pathology.Trueperella (formerly Arcanobacterium) pyogenes was isolated from three of four lung tissue samples at necrospy. Treatment with procaine penicillin for 42 consecutive days resulted in marked improvement with return to normal appetite and improvement in body condition in 8 of 12 cows (67%) where lesions did not extend more than 10-15 cm above the level of the olecranon on both sides of the chest.


Characterization of gastric volume responses and liquid emptying in functional dyspepsia and health by MRI or barostat and simultaneous C-acetate breath test.
The assessment of gastric accommodation and emptying by different methodologies provides inconsistent results. We aimed to compare magnetic resonance imaging (MRI), barostat and 13C-acetate breath test (BT) for the assessment of gastric volume responses and emptying in healthy controls (HC) and patients with functional dyspepsia (FD). Eight HC and eight FD patients underwent: (i) continuous BT with simultaneous MRI in the upright position after ingestion of isocaloric, 300 kcal, 200 and 800 mL meals, both labelled with 100 mg of (13)C-acetate; and (ii) BT with gastric barostat after ingestion of the 200 mL meal. MRI measured total gastric volume and gastric content volume (GCV) at baseline, after filling and during emptying. Meal emptying half-times (T(1/2)) for MRI and BT were calculated (mean +/- SD). We found: (i) Initial GCV was lower in FD than in HC (762 +/- 22 vs 810 +/- 52 mL, P < 0.04) after the 800 mL meal but not the 200 mL meal. T(1/2)(MRI) was shorter for the 800 mL than the 200 mL meal (P < 0.001), but similar in HC and FD (200 mL: HC 117 +/- 30 min vs FD 138 +/- 42 min, ns; 800 mL: HC 71 +/- 16 min vs FD 78 +/- 27 min, ns). In contrast, T(1/2)(BT) was similar between meals and groups (200 mL: HC 111 +/- 11 min vs FD 116 +/- 19 min; 800 mL: HC 114 +/- 14 min vs FD: 113 +/- 17 min). (ii) Barostat measurements showed similar postprandial volume increases between groups. We conclude that direct measurements by MRI provide a sensitive, non-invasive assessment of gastric accommodation and emptying after a meal. In contrast to MRI, BT did not detect faster emptying of high-volume compared to low-volume liquid nutrient meals in HC or FD.


Stability and Change in the Cognitive and Adaptive Behaviour Scores of Preschoolers with Autism Spectrum Disorder.
We examined the stability of cognitive and adaptive behaviour standard scores in children with autism spectrum disorder (ASD) between diagnosis and school entry approximately age 6. IQ increased 18 points in 2-year-olds, 12 points in 3-year-olds, and 9 points in 4-year-olds (N = 281). Adaptive behaviour scores increased 4 points across age groups (N = 289). At school entry, 24 % of children met criteria for intellectual disability (cognitive and adaptive behaviour scores <70). No children with both scores ≥70 at diagnosis later met criteria for intellectual disability. Outcomes were more variable for children with initial delays in both areas (in 57 %, both scores remained <70). Findings are relevant to clinical decision-making, including specification of intellectual disability in young children with ASD.


Bites by puff-adder (Bitis arietans) in Nigeria, and value of antivenom.
Ten patients bitten by the puff-adder (Bitis arietans) were studied in the North of Nigeria. Six showed severe local signs, and four also had evidence of systemic envenoming, including spontaneous bleeding with thrombocytopenia, hypotension, and bradycardia. Two patients died after developing circulatory collapse and renal failure. Antivenom and intravenous fluid restored blood pressure in two hypotensive patients, and antivenom probably prevented the development of local necrosis in four others with massive local swelling. Victims of B arietans who have swelling of more than half the bitten limb or show signs of systemic envenoming should be given at least 80 ml of specific polyvalent antivenom and watched carefully for signs of circulatory collapse. Debridement of necrotic tissue may be necessary.


Fast food consumption and gestational diabetes incidence in the SUN project.
Gestational diabetes prevalence is increasing, mostly because obesity among women of reproductive age is continuously escalating. We aimed to investigate the incidence of gestational diabetes according to the consumption of fast food in a cohort of university graduates. The prospective dynamic "Seguimiento Universidad de Navarra" (SUN) cohort included data of 3,048 women initially free of diabetes or previous gestational diabetes who reported at least one pregnancy between December 1999 and March 2011. Fast food consumption was assessed through a validated 136-item semi-quantitative food frequency questionnaire. Fast food was defined as the consumption of hamburgers, sausages, and pizza. Three categories of fast food were established: low (0-3 servings/month), intermediate (>3 servings/month and ≤2 servings/week) and high (>2 servings/week). Non-conditional logistic regression models were used to adjust for potential confounders. We identified 159 incident cases of gestational diabetes during follow-up. After adjusting for age, baseline body mass index, total energy intake, smoking, physical activity, family history of diabetes, cardiovascular disease/hypertension at baseline, parity, adherence to Mediterranean dietary pattern, alcohol intake, fiber intake, and sugar-sweetened soft drinks consumption, fast food consumption was significantly associated with a higher risk of incident gestational diabetes, with multivariate adjusted OR of 1.31 (95% conficence interval [CI]:0.81-2.13) and 1.86 (95% CI: 1.13-3.06) for the intermediate and high categories, respectively, versus the lowest category of baseline fast food consumption (p for linear trend: 0.007). Our results suggest that pre-pregnancy higher consumption of fast food is an independent risk factor for gestational diabetes.


Veno-venous extracorporeal membrane oxygenation with interatrial shunting: a novel approach to lung transplantation for patients in right ventricular failure.
This study evaluated the effectiveness of an atrial septostomy with veno-venous extracorporeal membrane oxygenation in alleviating high afterload right ventricular dysfunction while providing respiratory support. This technique could be applied as a bridge to lung transplantation. Sheep (56±3 kg) underwent a clamshell thoracotomy and hemodynamic instrumentation, including right ventricular pressure and cardiac output. Sheep with and without tricuspid insufficiency (n=5 each) were examined. While sheep were on extracorporeal membrane oxygenation, right ventricular failure was established by banding the pulmonary artery until cardiac output was 40% to 60% of baseline. An extracardiac atrial shunt was created with modified vascular grafts to examine the effect of shunt flow on hemodynamics. Hemodynamic data were thus collected at baseline, during right ventricular failure, and for 1 hour at 100% (fully open), 70%, 50%, and 30% of baseline shunt flow. Cardiac output was returned to baseline values (tricuspid insufficiency: 5.2±0.2 L/min, without tricuspid insufficiency: 5.3±1.2 L/min) with 100% shunt flow (tricuspid insufficiency: 4.8±1.1 L/min, without tricuspid insufficiency: 4.8±1.0 L/min; P=.15) but remained significantly lower than baseline at 70% to 30% shunt flow. At 100% shunt flow, tricuspid insufficiency shunt flow was 1.4±0.8 L/min and without tricuspid insufficiency shunt flow was 1.7±0.2 L/min. Right ventricular pressure was significantly elevated over baseline values at all shunt flows (P<.001). In the group without tricuspid insufficiency, all sheep died beginning at the 70% shunt condition, whereas all animals with tricuspid insufficiency survived the entire experiment. Normal arterial blood gases were maintained under all conditions. An atrial septostomy accompanied by veno-venous extracorporeal membrane oxygenation is capable of eliminating right ventricular failure while maintaining normal arterial blood gases if sufficient shunt flows are achieved. The presence of tricuspid insufficiency improves the efficacy of the shunt.


Evaluation of the AHRQ patient safety initiative: framework and approach.
Describe the evaluation performed of the patient safety initiative operated by the Agency for Healthcare Research and Quality (AHRQ). AHRQ PATIENT SAFETY INITIATIVE When patient safety became a national priority in 2000, Congress charged and funded AHRQ to improve health care safety. Over the next 6 years, AHRQ funded more than 300 research projects and other activities, addressing diverse patient safety issues and practices. AHRQ contracted with RAND in 2002 to perform a 4-year evaluation of the initiative, which was completed in 2006. This formative evaluation used the CIPP program evaluation model, which emphasizes multiple stakeholders' interests (e.g., patients, providers, funded researchers). We monitored the progress of the patient safety initiative and provided AHRQ annual feedback that assessed each year's activities, identifying issues and offering suggestions for actions by AHRQ. Given the size and complexity of the initiative, the evaluation needed to examine key individual components and synthesize results across them, and it also had to be responsive to changes in the initiative over time. We used a conceptual framework to bring together the disparate pieces to synthesize overall findings. The remaining articles in this issue describe selected results from this evaluation.


Indicators of smartphone addiction and stress score in university students.
Smartphone addiction is one of the most common non-drug addictions, accompanied by negative effects, such as depression, anxiety, self-disclosure, impaired academic performance, family life and human relationships. The aim of the present study was to assess the prevalence of a predisposition to smartphone use disorder in university students and to investigate the associations between the intensity of mobile phone use and several variables. A total of 150 students, from 2 universities from Timisoara, were included in the study. Students were requested to answer two questionnaires: Mobile Phone Dependence Questionnaire (MPDQ) and International Stress Management Association Questionnaire (ISMA). The study revealed a relative high number of students with a predisposition to smartphone use disorder, with significant correlations between indicators of smartphone addiction and stress scores. Also, significant correlations were obtained between MPDQ scores and students age, period of mobile phone use and ISMA.


The current availability of antiepileptic drugs in Zambia: implications for the ILAE/WHO "out of the shadows" campaign.
Recent concerns regarding antiepileptic drug (AED) availability in Zambia led us to conduct a study in the Lusaka and Southern Provinces to quantify the availability and cost of AEDs and assess determinants. Among 111 pharmacies, almost one-half did not carry AEDs (N = 54; 49.1%). Available AEDs were phenobarbitone (21; 18.9%), carbamazepine (27; 24.3%), valproic acid (4; 3.6%), and phenytoin (3; 2.7%). Adult out-of-pocket monthly costs ranged from US $7 to $30. Pediatric syrups were universally unavailable. Interviews revealed several barriers to AED provision, including that handling phenobarbitone (historically the most affordable AED) has become increasingly difficult because of newly enforced regulatory requirements. Personal communications with epilepsy-care providers in other low income countries suggest that this problem may be widespread. Improved enforcement of existing drug regulations may be contributing to the AED shortage. Social programs aimed at encouraging people with epilepsy to come "out of the shadows" must be preceded by improved AED access.


Transcutaneous computed bioconductance measurement in lung cancer: a treatment enabling technology useful for adjunctive risk stratification in the evaluation of suspicious pulmonary lesions.
Lung cancer is the number one cause of cancer deaths in North America and is rapidly increasing worldwide. Although there are advances being made in the multidisciplinary management and combined-modality therapies of lung cancers, most cases are still diagnosed in later noncurable stages. Early detection has hinged on clinical risk assessment and on the future possibility of screening by low-dose computed tomography of the chest; however, this will only vastly increase the number of indeterminate pulmonary lesions (IPLs) being detected. Given that the majority of radiographically detected lung lesions are benign, and tissue confirmation by various invasive biopsy tests has increased risks and costs, a noninvasive adjunctive test that can stratify likelihood of an indeterminate lung lesion as malignant or benign will be a useful treatment-enabling technology to speed up diagnosis and treatment of lung cancers at a more curable stage and defer unnecessary invasive procedures that have potential for harm. Measurement of transcutaneous bioconductance using the differential conductivity properties of cancerous versus benign tissue has been previously demonstrated on nonlung lesions. Thus, it has the potential of being a noninvasive, simple-to-perform and repeatable test that may be valuable in assessing lung lesions. In this prospective study of subjects with known thoracic malignancies, computed bioconductance measurements discriminated between malignant lesions (29 primary lung cancers) from benign pathology (12) across a range of IPL sizes (0.8 cm and greater) with a sensitivity of 89.7% (positive predictive value 96.3%) and specificity of 91.7% (negative predictive value 78.5%). The technology seems to be effective across a range of tumor thoracic locations, cell types, and stages. Additional cohorts of subjects will be used to validate testing and for refinement of the current algorithm, which at present has a test performance with a receiver operating characteristic of 90.7%. Noninvasive transcutaneous computed bioconductance measurement can become a standard risk assessment and therapy-enabling tool in the evaluation of IPLs.


Predictive value of prospective memory for remission in first-episode schizophrenia.
The study examined the rate of remission in individuals experiencing a first episode of schizophrenia (FES) in China and explored predictors of remission in the acute phase of the illness. Fifty-five FES patients were randomly treated with risperidone, olanzapine, or aripiprazole at therapeutic doses for 8 weeks, and their clinical profiles and cognition were assessed using standardized assessment instruments at entry and the end of the study. Of the 55 patients, 30 (54.5%) remitted by the end of the 8-week study. In univariate analyses, shorter duration of untreated psychosis, higher scores on both the time-based prospective memory (TBPM) and event-based prospective memory tasks and the Hopkins Verbal Learning Test-revised, and less severe negative symptoms were significantly associated with remission. In stepwise multiple logistic regression analyses, only higher scores on the TBPM significantly predicted remission. Individuals having higher scores reflecting better TBPM at baseline were more likely to achieve remission after 8 weeks of optimized antipsychotic treatment. TPBM may be useful in helping clinicians identify those FES patients most likely to achieve a favorable treatment response.


Relaxation in x-space magnetic particle imaging.
Magnetic particle imaging (MPI) is a new imaging modality that noninvasively images the spatial distribution of superparamagnetic iron oxide nanoparticles (SPIOs). MPI has demonstrated high contrast and zero attenuation with depth, and MPI promises superior safety compared to current angiography methods, X-ray, computed tomography, and magnetic resonance imaging angiography. Nanoparticle relaxation can delay the SPIO magnetization, and in this work we investigate the open problem of the role relaxation plays in MPI scanning and its effect on the image. We begin by amending the x-space theory of MPI to include nanoparticle relaxation effects. We then validate the amended theory with experiments from a Berkeley x-space relaxometer and a Berkeley x-space projection MPI scanner. Our theory and experimental data indicate that relaxation reduces SNR and asymmetrically blurs the image in the scanning direction. While relaxation effects can have deleterious effects on the MPI scan, we show theoretically and experimentally that x-space reconstruction remains robust in the presence of relaxation. Furthermore, the role of relaxation in x-space theory provides guidance as we develop methods to minimize relaxation-induced blurring. This will be an important future area of research for the MPI community.


Primary renal carcinoid: treatment and prognosis.
Primary carcinoid tumors of the kidney are very rare, malignant tumors consisting of neuroendocrine cells. The pathogenesis of renal carcinoid is unclear because neuroendocrine cells are not normally found in adult renal parenchyma. Electron microscopy, immunohistochemistry, octreotide scan, positron emission tomography along with conventional radiographic imaging techniques are used in diagnosis and follow-up. Presenting symptoms usually include flank pain and haematuria. Early stage disease is treated with surgery only. However, randomized trials are lacking because of the very low number of reported cases. Thus, the role of debulking surgery, chemotherapy, radiotherapy, octreotide and targeted therapy in the management of advanced disease remains an open question. In this article the clinicopathologic features and prognosis of this very rare disease along with treatment outcomes of the reported cases are reviewed. In addition, we report a new case of a metastatic primary renal atypical carcinoid tumor treated with octreotide therapy.


A global horizon scan of issues impacting marine and coastal biodiversity conservation.
The biodiversity of marine and coastal habitats is experiencing unprecedented change. While there are well-known drivers of these changes, such as overexploitation, climate change and pollution, there are also relatively unknown emerging issues that are poorly understood or recognized that have potentially positive or negative impacts on marine and coastal ecosystems. In this inaugural Marine and Coastal Horizon Scan, we brought together 30 scientists, policymakers and practitioners with transdisciplinary expertise in marine and coastal systems to identify new issues that are likely to have a significant impact on the functioning and conservation of marine and coastal biodiversity over the next 5-10 years. Based on a modified Delphi voting process, the final 15 issues presented were distilled from a list of 75 submitted by participants at the start of the process. These issues are grouped into three categories: ecosystem impacts, for example the impact of wildfires and the effect of poleward migration on equatorial biodiversity; resource exploitation, including an increase in the trade of fish swim bladders and increased exploitation of marine collagens; and new technologies, such as soft robotics and new biodegradable products. Our early identification of these issues and their potential impacts on marine and coastal biodiversity will support scientists, conservationists, resource managers and policymakers to address the challenges facing marine ecosystems.


Design, synthesis, and evaluation of Bothrops venom serine protease peptidic inhibitors.
In Central and South America, snakebite envenomation is mainly caused by Bothrops spp. snakes, whose venoms feature significant biochemical richness, including serine proteases. The available bothropic antivenoms are efficient in avoiding fatalities, but do not completely neutralize venom serine proteases, which are co-responsible for some disorders observed during envenomation. In order to search for tools to improve the antivenom's, 6-mer peptides were designed based on a specific substrate for Bothrops jararaca venom serine proteases, and then synthesized, with the intention to selectively inhibit these enzymes. Using batroxobin as a snake venom serine protease model, two structurally similar inhibitor peptides were identified. When tested on B. jararaca venom, one of the new inhibitors displayed a good potential to inhibit the activity of the venom serine proteases. These inhibitors do not affect human serine proteases as human factor Xa and thrombin, due to their selectivity. Our study identified two small peptides able to inhibit bothropic serine proteases, but not human ones, can be used as tools to enhance knowledge of the venom composition and function. Moreover, one promising peptide (pepC) was identified that can be explored in the search for improving Bothrops spp. envenomation treatment.


An increase in dietary n-3 fatty acids decreases a marker of bone resorption in humans.
Human, animal, and in vitro research indicates a beneficial effect of appropriate amounts of omega-3 (n-3) polyunsaturated fatty acids (PUFA) on bone health. This is the first controlled feeding study in humans to evaluate the effect of dietary plant-derived n-3 PUFA on bone turnover, assessed by serum concentrations of N-telopeptides (NTx) and bone-specific alkaline phosphatase (BSAP). Subjects (n = 23) consumed each diet for 6 weeks in a randomized, 3-period crossover design: 1) Average American Diet (AAD; [34% total fat, 13% saturated fatty acids (SFA), 13% monounsaturated fatty acids (MUFA), 9% PUFA (7.7% LA, 0.8% ALA)]), 2) Linoleic Acid Diet (LA; [37% total fat, 9% SFA, 12% MUFA, 16% PUFA (12.6% LA, 3.6% ALA)]), and 3) alpha-Linolenic Acid Diet (ALA; [38% total fat, 8% SFA, 12% MUFA, 17% PUFA (10.5% LA, 6.5% ALA)]). Walnuts and flaxseed oil were the predominant sources of ALA. NTx levels were significantly lower following the ALA diet (13.20 +/- 1.21 nM BCE), relative to the AAD (15.59 +/- 1.21 nM BCE) (p < 0.05). Mean NTx level following the LA diet was 13.80 +/- 1.21 nM BCE. There was no change in levels of BSAP across the three diets. Concentrations of NTx were positively correlated with the pro-inflammatory cytokine TNFalpha for all three diets. The results indicate that plant sources of dietary n-3 PUFA may have a protective effect on bone metabolism via a decrease in bone resorption in the presence of consistent levels of bone formation.


Nitrogen and carbon/nitrogen dynamics in arbuscular mycorrhiza: the great unknown.
Many studies have established that arbuscular mycorrhizal fungi transfer N to the host plant. However, the role and importance of arbuscular mycorrhiza (AM) in plant N nutrition is still uncertain, as are the C/N interactions within the symbiosis. Published reports provide differing, and often contradictory, results that are difficult to combine in a coherent framework. This review explores questions such as: What makes the difference between a positive and a negative effect of AM on plant N nutrition? Is the mycorrhizal N response (MNR) correlated to the mycorrhizal growth response (MGR), and how or under which conditions? Is the MNR effect on plant growth C mediated? Is plant C investment on fungal growth related to N needs or N benefit? How is the N for C trade between symbionts regulated? The patternless nature of current knowledge is made evident, and possible reasons for this are discussed.


Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis.
Inward-rectifying potassium (K+(in)) channels in guard cells have been suggested to provide a pathway for K+ uptake into guard cells during stomatal opening. To test the proposed role of guard cell K+(in) channels in light-induced stomatal opening, transgenic Arabidopsis plants were generated that expressed dominant negative point mutations in the K+(in) channel subunit KAT1. Patch-clamp analyses with transgenic guard cells from independent lines showed that K+(in) current magnitudes were reduced by approximately 75% compared with vector-transformed controls at -180 mV, which resulted in reduction in light-induced stomatal opening by 38% to 45% compared with vector-transformed controls. Analyses of intracellular K+ content using both sodium hexanitrocobaltate (III) and elemental x-ray microanalyses showed that light-induced K+ uptake was also significantly reduced in guard cells of K+(in) channel depressor lines. These findings support the model that K+(in) channels contribute to K+ uptake during light-induced stomatal opening. Furthermore, transpirational water loss from leaves was reduced in the K+(in) channel depressor lines. Comparisons of guard cell K+(in) current magnitudes among four different transgenic lines with different K+(in) current magnitudes show the range of activities of K+(in) channels required for guard cell K+ uptake during light-induced stomatal opening.


Racial disparities in trajectories of dental caries experience.
This study charted the trajectories of dental caries, including decayed teeth, missing teeth and filled teeth among older Americans over a 5-year period. In particular, it focused on racial differences in the levels of and rates of change in dental caries experience. Data came from the Piedmont Dental Study. The sample included 810 older Americans who were dentate at the baseline with up to 4 repeated observations between 1988 and 1994. Hierarchical linear models were employed in depicting intrapersonal and interpersonal differences in dental caries experience. Different measures of caries outcomes exhibited distinct trajectories. On average, the number of decayed teeth decreased over time, whereas missing teeth increased. In contrast, the number of filled teeth remained stable during a 5-year period. Relative to their white counterparts, older black Americans had more decayed teeth and missing teeth but fewer filled teeth. Blacks and whites differed in the levels of dental caries but not in their rates of change except for missing teeth. Even when demographic and socioeconomic attributes were adjusted, racial variations in dental caries experience remained significant. Although significantly correlated, various dental caries outcomes move along different paths over time. In view of the persistent racial disparities in dental caries trajectories, future interventions to minimize such variations among older Americans in the levels of and the rates of change in dental caries experience are clearly warranted.


One "shape" fits all: the orientation bandwidth of contour integration.
The ability of human participants to integrate fragmented stimulus elements into perceived coherent contours (amidst a field of distracter elements) has been intensively studied across a large number of contour element parameters, ranging from luminance contrast and chromaticity to motion and stereo. The evidence suggests that contour integration performance depends on the low-level Fourier properties of the stimuli. Thus, to understand contour integration, it would be advantageous to understand the properties of the low-level filters that the visual system uses to process contour stimuli. We addressed this issue by examining the role of stimulus element orientation bandwidth in contour integration, a previously unexplored area. We carried out three psychophysical experiments, and then simulated all of the experiments using a recently developed two-stage filter-overlap model whereby the contour grouping occurs by virtue of the overlap between the filter responses to different elements. The first stage of the model responds to the elements, while the second stage integrates the responses along the contour. We found that the first stage had to be fairly broadly tuned for orientation to account for our results. The model showed a very good fit to a large data set with relatively few free parameters, suggesting that this class of model may have an important role to play in helping us to better understand the mechanisms of contour integration.


Modulation of Radiation Response by the Tetrahydrobiopterin Pathway.
Ionizing radiation (IR) is an integral component of our lives due to highly prevalent sources such as medical, environmental, and/or accidental. Thus, understanding of the mechanisms by which radiation toxicity develops is crucial to address acute and chronic health problems that occur following IR exposure. Immediate formation of IR-induced free radicals as well as their persistent effects on metabolism through subsequent alterations in redox mediated inter- and intracellular processes are globally accepted as significant contributors to early and late effects of IR exposure. This includes but is not limited to cytotoxicity, genomic instability, fibrosis and inflammation. Damage to the critical biomolecules leading to detrimental long-term alterations in metabolic redox homeostasis following IR exposure has been the focus of various independent investigations over last several decades. The growth of the "omics" technologies during the past decade has enabled integration of "data from traditional radiobiology research", with data from metabolomics studies. This review will focus on the role of tetrahydrobiopterin (BH4), an understudied redox-sensitive metabolite, plays in the pathogenesis of post-irradiation normal tissue injury as well as how the metabolomic readout of BH4 metabolism fits in the overall picture of disrupted oxidative metabolism following IR exposure.


A Phase II Study of Avelumab Monotherapy in Patients with Mismatch Repair-Deficient/Microsatellite Instability-High or POLE-Mutated Metastatic or Unresectable Colorectal Cancer.
We evaluated the efficacy and safety of avelumab, an anti-PD-L1 antibody, in patients with metastatic or unresectable colorectal cancer (mCRC) with mismatch repair deficiency (dMMR)/microsatellite instability-high (MSI-H) or POLE mutations. In this prospective, open-label, multicenter phase II study, 33 patients with mCRC harboring dMMR/MSI-H or POLE mutations after failure of ≥1st-line chemotherapy received avelumab 10 mg/kg every 2 weeks. dMMR/MSI-H was confirmed with immunohistochemical staining (IHC) by loss of expression of MMR proteins or polymerase chain reaction (PCR) for microsatellite sequences. POLE mutation was confirmed by next-generation sequencing (NGS). The primary endpoint was the objective response rate (ORR) by Response Evaluation Criteria in Solid Tumors ver. 1.1. The median age was 60 years, and 78.8% were male. Thirty patients were dMMR/MSI-H and three had POLE mutations. The ORR was 24.2%, and all of the responders were dMMR/MSI-H. For 21 patients with MSI-H by PCR or NGS, the ORR was 28.6%. At a median follow-up duration of 16.3 months, median progression-free survival and overall survival were 3.9 and 13.2 months in all patients, and 8.1 months and not reached, respectively, in patients with MSI-H by PCR or NGS. Dose interruption and discontinuation due to treatment-related adverse events occurred in four and two patients, respectively, with no treatment-related deaths. Avelumab displayed antitumor activity with manageable toxicity in patients with previously treated mCRC harboring dMMR/MSI-H. Diagnosis of dMMR/MSI-H with PCR or NGS could be complementary to IHC to select patients who would benefit from immunotherapy.


Long-range proton-coupled electron transfer in the Escherichia coli class Ia ribonucleotide reductase.
Escherichia coli class Ia ribonucleotide reductase (RNR) catalyzes the conversion of nucleotides to 2'-deoxynucleotides using a radical mechanism. Each turnover requires radical transfer from an assembled diferric tyrosyl radical (Y•) cofactor to the enzyme active site over 35 Å away. This unprecedented reaction occurs via an amino acid radical hopping pathway spanning two protein subunits. To study the mechanism of radical transport in RNR, a suite of biochemical approaches have been developed, such as site-directed incorporation of unnatural amino acids with altered electronic properties and photochemical generation of radical intermediates. The resulting variant RNRs have been investigated using a variety of time-resolved physical techniques, including transient absorption and stopped-flow UV-Vis spectroscopy, as well as rapid freeze-quench EPR, ENDOR, and PELDOR spectroscopic methods. The data suggest that radical transport occurs via proton-coupled electron transfer (PCET) and that the protein structure has evolved to manage the proton and electron transfer co-ordinates in order to prevent 'off-pathway' reactivity and build-up of oxidised intermediates. Thus, precise design and control over the factors that govern PCET is key to enabling reversible and long-range charge transport by amino acid radicals in RNR.


Racial, ethnic, and insurance status disparities in use of posthospitalization care after trauma.
Posthospitalization care is important for recovery after trauma. Disadvantaged populations, like racial or ethnic minorities and the uninsured, make up substantial percentages of trauma patients, but their use of posthospitalization facilities is unknown. This study analyzed National Trauma Data Bank admissions from 2007 for 18- to 64-year-olds and estimated relative risk ratios (RRR) of discharge to posthospitalization facilities--home, home health, rehabilitation, or nursing facility--by race, ethnicity, and insurance. Multinomial logistic regression adjusted for patient characteristics including age, sex, Injury Severity Score, mechanism of injury, and length of stay, among others. There were 136,239 patients who met inclusion criteria with data for analysis. Most patients were discharged home (78.9%); fewer went to home health (3.3%), rehabilitation (5.0%), and nursing facilities (5.4%). When compared with white patients in adjusted analysis, relative risk ratios of discharge to rehabilitation were 0.61 (95% CI 0.56, 0.66) and 0.44 (95% CI 0.40, 0.49) for blacks and Hispanics, respectively. Compared with privately insured white patients, Hispanics had lower rates of discharge to rehabilitation whether privately insured (RRR 0.45, 95% CI 0.40, 0.52), publicly insured (RRR 0.51, 95% CI 0.42, 0.61), or uninsured (RRR 0.20, 95% CI 0.17, 0.24). Black patients had similarly low rates: private (RRR 0.63, 95% CI 0.56, 0.71), public (RRR 0.72, 95% CI 0.63, 0.82), or uninsured (RRR 0.27, 95% CI 0.23, 0.32). Relative risk ratios of discharge to home health or nursing facilities showed similar trends among blacks and Hispanics regardless of insurance, except for black patients with insurance whose discharge to nursing facilities was similar to their white counterparts. Disadvantaged populations have more limited use of posthospitalization care such as rehabilitation after trauma, suggesting a potential improvement in trauma care for the underprivileged.


Urinary 8-hydroxy-2'-deoxyguanosine as a biological marker of in vivo oxidative DNA damage.
DNA is subject to constant oxidative damage from endogenous oxidants. The oxidized DNA is continuously repaired and the oxidized bases are excreted in the urine. A simple routine analytical procedure is described for urinary 8-hydroxy-2'-deoxyguanosine, an oxidative DNA damage adduct, as an indicator of oxidative damage in humans and rodents. This adduct was purified from human urine and characterized. The described assay employs a series of solid-phase extraction steps that separate 8-hydroxy-2'-deoxyguanosine from other urinary constituents, followed by analysis by gradient reversed-phase HPLC coupled to a dual-electrode high-efficiency electrochemical detection system. Analysis of urine from three species by this method indicates that mice excrete approximately 3.3-fold more 8-hydroxy-2'-deoxyguanosine than humans (582 vs. 178 residues per cell per day), a result that supports the proposal that oxidative damage to DNA increases in proportion to species-specific basal metabolic rates.


Lymphatic mapping with sentinel node biopsy in pediatric patients.
Lymphatic mapping with sentinel node biopsy is used widely in adult melanoma and breast cancer to determine nodal status without the morbidity associated with elective lymph node dissection. This technique can be used in children to determine lymph node status with limited dissection and accurate interpretation. The authors report their initial experience. The charts of patients who underwent lymphatic mapping with sentinel node biopsy were reviewed retrospectively. Lymphoscintigraphy was performed in patients with truncal lesions 24 hours before surgery to determine the draining nodal basin (for surgical mapping). The tumors were injected 1 hour preoperatively with technetium sulfur colloid and in the operating room with Lymphazurin blue. The draining basin was examined using a radioisotope detector. The blue nodes with high counts were localized and removed. If nodal metastases were identified, lymph node dissection was recommended. Four patients were injected only with Lymphazurin blue. Thirteen children (7 girls, 6 boys; mean age, 7 years) underwent lymphatic mapping with sentinel node biopsy. The tumor types were as follows: 8 malignant melanoma (6 extremity, 2 truncal), 1 malignant peripheral nerve sheath tumor, 1 alveolar soft part sarcoma, and 3 rhabdomyosarcoma. A mean of 2.4 nodes (range, 1 to 6) were removed from each patient. Six patients had a positive sentinel node. Formal lymph node dissection was performed on 4 of the 6 patients, 1 of whom had further nodal disease with 2 of 13 nodes containing micrometastases. One of the 6 patients refused lymph node dissection and adjuvant therapy; the final patient had rhabdomyosarcoma, a malignancy for which lymph node dissection is not indicated. Pulmonary metastasis developed 26 months after diagnoses in the patient with alveolar soft part sarcoma and a negative sentinel node. This patient was injected only with Lymphazurin blue at the time of sentinel node biopsy and refused adjuvant therapy. There have been no other recurrences. There were no complications related to lymphatic mapping or sentinel node biopsy. Lymphatic mapping with sentinel node biopsy, using both technetium-labeled sulfur colloid and Lymphazurin blue, can be performed safely in pediatric skin and soft tissue malignancies. Further study with long-term follow-up will determine the utility and accuracy of this technique in pediatric malignancies.


IL-33 and thymic stromal lymphopoietin mediate immune pathology in response to chronic airborne allergen exposure.
Humans are frequently exposed to various airborne allergens in the atmospheric environment. These allergens may trigger a complex network of immune responses in the airways, resulting in asthma and other chronic airway diseases. In this study, we investigated the immunological mechanisms involved in the pathological changes induced by chronic exposure to multiple airborne allergens. Naive mice were exposed intranasally to a combination of common airborne allergens, including the house dust mite, Alternaria, and Aspergillus, for up to 8 wk. These allergens acted synergistically and induced robust eosinophilic airway inflammation, specific IgE Ab production, type 2 cytokine response, and airway hyperresponsiveness in 4 wk, followed by airway remodeling in 8 wk. Increased lung infiltration of T cells, B cells, and type 2 innate lymphoid cells was observed. CD4(+) T cells and type 2 innate lymphoid cells contributed to the sources of IL-5 and IL-13, suggesting involvement of both innate and adaptive immunity in this model. The lung levels of IL-33 increased quickly within several hours after allergen exposure and continued to rise throughout the chronic phase of inflammation. Mice deficient in IL-33R (Il1rl1(-/-)) and thymic stromal lymphopoietin receptor (Tslpr(-/-)) showed significant reduction in airway inflammation, IgE Ab levels, and airway hyperresponsiveness. In contrast, mice deficient in IL-25R or IL-1R showed minimal differences as compared with wild-type animals. Thus, chronic exposure to natural airborne allergens triggers a network of innate and adaptive type 2 immune responses and airway pathology, and IL-33 and thymic stromal lymphopoietin most likely play key roles in this process.


Efficacy of ChAdOx1 nCoV-19 (AZD1222) vaccine against SARS-CoV-2 lineages circulating in Brazil.
Several COVID-19 vaccines have shown good efficacy in clinical trials, but there remains uncertainty about the efficacy of vaccines against different variants. Here, we investigate the efficacy of ChAdOx1 nCoV-19 (AZD1222) against symptomatic COVID-19 in a post-hoc exploratory analysis of a Phase 3 randomised trial in Brazil (trial registration ISRCTN89951424). Nose and throat swabs were tested by PCR in symptomatic participants. Sequencing and genotyping of swabs were performed to determine the lineages of SARS-CoV-2 circulating during the study. Protection against any symptomatic COVID-19 caused by the Zeta (P.2) variant was assessed in 153 cases with vaccine efficacy (VE) of 69% (95% CI 55, 78). 49 cases of B.1.1.28 occurred and VE was 73% (46, 86). The Gamma (P.1) variant arose later in the trial and fewer cases (N = 18) were available for analysis. VE was 64% (-2, 87). ChAdOx1 nCoV-19 provided 95% protection (95% CI 61%, 99%) against hospitalisation due to COVID-19. In summary, we report that ChAdOx1 nCoV-19 protects against emerging variants in Brazil despite the presence of the spike protein mutation E484K.


Time in treatment: Examining mental illness trajectories across inpatient psychiatric treatment.
Early discharge or reduced length of stay for inpatient psychiatric patients is related to increased readmission rates and worse clinical outcomes including increased risk for suicide. Trajectories of mental illness outcomes have been identified as an important method for predicting the optimal length of stay but the distinguishing factors that separate trajectories remain unclear. We sought to identify the distinct classes of patients who demonstrated similar trajectories of mental illness over the course of inpatient treatment, and we explore the patient characteristics associated with these mental illness trajectories. We used data (N = 3406) from an inpatient psychiatric hospital with intermediate lengths of stay. Using growth mixture modeling, latent mental illness scores were derived from six mental illness indicators: psychological flexibility, emotion regulation problems, anxiety, depression, suicidal ideation, and disability. The patients were grouped into three distinct trajectory classes: (1) High-Risk, Rapid Improvement (HR-RI); (2) Low-Risk, Gradual Improvement (LR-GI); and (3) High-Risk, Gradual Improvement (HR-GI). The HR-GI was significantly younger than the other two classes. The HR-GI had significantly more female patients than males, while the LR-GI had more male patients than females. Our findings indicated that younger females had more severe mental illness at admission and only gradual improvement during the inpatient treatment period, and they remained in treatment for longer lengths of stay, than older males.


Unexplained regression in Down syndrome: 35 cases from an international Down syndrome database.
An entity of regression in Down syndrome (DS) exists that affects adolescents and young adults and differs from autism spectrum disorder and Alzheimer disease. Since 2017, an international consortium of DS clinics assembled a database of patients with unexplained regression and age- and sex-matched controls. Standardized data on clinical symptoms and tiered medical evaluations were collected. Elements of the proposed definition of unexplained regression in DS were analyzed by paired comparisons between regression cases and matched controls. We identified 35 patients with DS and unexplained regression, with a mean age at regression of 17.5 years. Diagnostic features differed substantially between regression cases and matched controls (p < 0.001 for all but externalizing behaviors). Patients with regression had four times as many mental health concerns (p < 0.001), six times as many stressors (p < 0.001), and seven times as many depressive symptoms (p < 0.001). Tiered medical evaluation most often identified abnormalities in vitamin D 25-OH levels, polysomnograms, thyroid peroxidase antibodies, and celiac screens. Analysis of the subset of patients with nondiagnostic medical evaluations reinforced the proposed definition. Our case-control evidence supports a proposed definition of unexplained regression in Down syndrome. Establishing this clinical definition supports future research and investigation of an underlying mechanism.


Corpus allatum activity in vitro during ovarian maturation in the desert locust, Schistocerca gregaria.
1. Radiochemical in vitro assays show that there are large and rapid changes in the spontaneous rate of juvenile hormone synthesis and release during the course of sexual maturation in the locust. 2. Parallel observations on glands incubated with farnesenic acid show that the rate-limiting step is always prior to the stage of esterification of farnesenic acid to the final intermediate, methyl farnesoate. 3. Corresponding changes in oocyte morphometrics do not reveal any clear correlation between endocrine activity of the corpus allatum and either the induction or maintenance of rapid vitellogenesis. 4. Peaks of synthetic activity in the corpus allatum correspond well with the onset of previtellogenic growth in the oocytes. 5. The data do not provide any evidence that 'corpus allatum insufficiency' is responsible for resorption of growing oocytes. 6. It is concluded that short-term in vitro radio-assays provide a valid method for estimating quantitatively the physiological activity of the corpus allatum.


There is no such thing as ageing, and cancer is not related to it.
Several separate cellular processes have to accumulate in a normal cell to alter it into the seed of a growing carcinoma. Even though cancer is much commoner in the old than in the young, there is no good evidence whatever that these separate processes have any systematic tendency to take place more readily among old than among young adults. (Indeed, there are some instances in which carcinogenic treatments actually elicit cancer less rapidly among the old!) There are obvious evolutionary reasons why substantial cancer risks should be delayed until the end of the usual lifespan, and it appears that this is achieved chiefly not by having the component processes of neoplastic transformation themselves particularly dependent on age, but simply by requiring not one, but several, of them en route from full normality to full malignancy, and by giving at least some of them an extraordinarily low daily probability. The daily probabilities of these separate events are, of course, under evolutionary influence, and some of them appear to have changed by orders of magnitude over the tens of millions of years of evolution that separate humanity from various short-lived animals.


Bayesian uncertainty quantification in linear models for diffusion MRI.
Diffusion MRI (dMRI) is a valuable tool in the assessment of tissue microstructure. By fitting a model to the dMRI signal it is possible to derive various quantitative features. Several of the most popular dMRI signal models are expansions in an appropriately chosen basis, where the coefficients are determined using some variation of least-squares. However, such approaches lack any notion of uncertainty, which could be valuable in e.g. group analyses. In this work, we use a probabilistic interpretation of linear least-squares methods to recast popular dMRI models as Bayesian ones. This makes it possible to quantify the uncertainty of any derived quantity. In particular, for quantities that are affine functions of the coefficients, the posterior distribution can be expressed in closed-form. We simulated measurements from single- and double-tensor models where the correct values of several quantities are known, to validate that the theoretically derived quantiles agree with those observed empirically. We included results from residual bootstrap for comparison and found good agreement. The validation employed several different models: Diffusion Tensor Imaging (DTI), Mean Apparent Propagator MRI (MAP-MRI) and Constrained Spherical Deconvolution (CSD). We also used in vivo data to visualize maps of quantitative features and corresponding uncertainties, and to show how our approach can be used in a group analysis to downweight subjects with high uncertainty. In summary, we convert successful linear models for dMRI signal estimation to probabilistic models, capable of accurate uncertainty quantification.


Image Geo-Localization Based on Multiple Nearest Neighbor Feature Matching Using Generalized Graphs.
In this paper, we present a new framework for geo-locating an image utilizing a novel multiple nearest neighbor feature matching method using Generalized Minimum Clique Graphs (GMCP). First, we extract local features (e.g., SIFT) from the query image and retrieve a number of nearest neighbors for each query feature from the reference data set. Next, we apply our GMCP-based feature matching to select a single nearest neighbor for each query feature such that all matches are globally consistent. Our approach to feature matching is based on the proposition that the first nearest neighbors are not necessarily the best choices for finding correspondences in image matching. Therefore, the proposed method considers multiple reference nearest neighbors as potential matches and selects the correct ones by enforcing consistency among their global features (e.g., GIST) using GMCP. In this context, we argue that using a robust distance function for finding the similarity between the global features is essential for the cases where the query matches multiple reference images with dissimilar global features. Towards this end, we propose a robust distance function based on the Gaussian Radial Basis Function (G-RBF). We evaluated the proposed framework on a new data set of 102k street view images; the experiments show it outperforms the state of the art by 10 percent.


Analysis of the treatment plan evaluation process in radiotherapy through eye tracking.
Treatment plan evaluation is a clinical decision-making problem that involves visual search and analysis in a contextually rich environment, including delineated structures and isodose lines superposed on CT data. It is a two-step process that includes visual analysis and clinical reasoning. In this work, we used eye tracking methods to gain more knowledge about the treatment plan evaluation process in radiation therapy. Dose distributions on a single transverse slice of ten prostate cancer treatment plans were presented to eight decision makers. Their eye movements and fixations were recorded with an EyeLink1000 remote eye-tracker. Total evaluation time, dwell time, number and duration of fixations on pre-segmented areas of interest were measured. The main structures receiving more and longer fixations (PTV, rectum, bladder) correspond to the main trade-offs evaluated in a typical prostate plan. Radiation oncologists made more fixations on the main structures compared to the medical physicists. Radiation oncologists fixated longer on the rectum when visited for the first time, while medical physicists fixated longer on the bladder. Our results quantify differences in the visual evaluation patterns between radiation oncologists and medical physicists, which indicate differences in their decision making strategies.


Exercise-induced neuronal plasticity in central autonomic networks: role in cardiovascular control.
It is now well established that brain plasticity is an inherent property not only of the developing but also of the adult brain. Numerous beneficial effects of exercise, including improved memory, cognitive function and neuroprotection, have been shown to involve an important neuroplastic component. However, whether major adaptive cardiovascular adjustments during exercise, needed to ensure proper blood perfusion of peripheral tissues, also require brain neuroplasticity, is presently unknown. This review will critically evaluate current knowledge on proposed mechanisms that are likely to underlie the continuous resetting of baroreflex control of heart rate during/after exercise and following exercise training. Accumulating evidence indicates that not only somatosensory afferents (conveyed by skeletal muscle receptors, baroreceptors and/or cardiopulmonary receptors) but also projections arising from central command neurons (in particular, peptidergic hypothalamic pre-autonomic neurons) converge into the nucleus tractus solitarii (NTS) in the dorsal brainstem, to co-ordinate complex cardiovascular adaptations during dynamic exercise. This review focuses in particular on a reciprocally interconnected network between the NTS and the hypothalamic paraventricular nucleus (PVN), which is proposed to act as a pivotal anatomical and functional substrate underlying integrative feedforward and feedback cardiovascular adjustments during exercise. Recent findings supporting neuroplastic adaptive changes within the NTS-PVN reciprocal network (e.g. remodelling of afferent inputs, structural and functional neuronal plasticity and changes in neurotransmitter content) will be discussed within the context of their role as important underlying cellular mechanisms supporting the tonic activation and improved efficacy of these central pathways in response to circulatory demand at rest and during exercise, both in sedentary and in trained individuals. We hope this review will stimulate more comprehensive studies aimed at understanding cellular and molecular mechanisms within CNS neuronal networks that contribute to exercise-induced neuroplasticity and cardiovascular adjustments.


Swimming against the tide: progress and challenges in our understanding of colicin translocation.
Colicins are folded protein toxins that face the formidable task of translocating across one or both of the Escherichia coli cell membranes in order to induce cell death. This translocation is achieved by parasitizing host proteins. There has been much recent progress in our understanding of the early stages of colicin entry, including the binding of outer-membrane nutrient transporters and porins and the subsequent recruitment of periplasmic and inner-membrane proteins that, together, trigger translocation. As well as providing insights into how these toxins enter cells, these studies have highlighted some surprising similarities in the modes of action of the systems that colicins subvert.


Mechanics of active surfaces.
We derive a fully covariant theory of the mechanics of active surfaces. This theory provides a framework for the study of active biological or chemical processes at surfaces, such as the cell cortex, the mechanics of epithelial tissues, or reconstituted active systems on surfaces. We introduce forces and torques acting on a surface, and derive the associated force balance conditions. We show that surfaces with in-plane rotational symmetry can have broken up-down, chiral, or planar-chiral symmetry. We discuss the rate of entropy production in the surface and write linear constitutive relations that satisfy the Onsager relations. We show that the bending modulus, the spontaneous curvature, and the surface tension of a passive surface are renormalized by active terms. Finally, we identify active terms which are not found in a passive theory and discuss examples of shape instabilities that are related to active processes in the surface.


Collaborative nursing education programs: challenges and issues.
Collaborative nursing education programs have been offered to facilitate access to baccalaureate-level nursing education. Our Collaborative Nursing Program involved 10 institutional partners and has been one of the largest of such programs. The collaborative approach to nursing education has been identified as an important model; the benefits include optimal use of resources and opportunities to develop and share knowledge across institutions. However, there has been little public discussion of the issues and challenges that emerge, including differing cultures, priorities, vulnerabilities, goals and aspirations between colleges and universities; desire to preserve autonomy and uniqueness; and complexity of approval and accreditation processes. Some of our college partners have chosen to offer an independent applied degree in nursing rather than continuing in a collaborative academic degree program. This paper describes the challenges inherent in maintaining quality of the degrees and strategies to increase the likelihood of continuing collaboration. Clarity and transparency are vital, and supportive programs involving mentorship of educators can foster increasing autonomy of colleges. Collaborative nursing programs pose many challenges, and their future will hinge on understanding mutual goals and expectations.


Lipid-based emulsion system as non-viral gene carriers.
The genetic materials for systemic administration meet a number of hurdles before they reach the nucleus of the target cells, such as enzymatic degradation in the bloodstream, extravascularization around the target tissue, endocytosis by the target cells, and endosomal escape of the genes. Therefore, there have been tremendous needs of effective gene carriers that can deliver the genetic materials to the target site. Of numerous approaches, recent studies have demonstrated that the lipid-based emulsion systems have the high potential as non-viral gene carriers: 1 lipid emulsions are biocompatible because their major constituents are composed of the non-toxic oils and amphiphilic lipids; 2 the cationic lipid emulsions can form nano-sized complexes with negatively charged DNAs, through which the genetic materials can be protected from the enzymatic degradation in the body fluids; 3 The emulsion/DNA complexes are shown to be stable in the bloodstream since their surfaces are rarely recognized by the immune-related cells and serum proteins; and 4 the surfaces of the emulsion complexes are readily modified by varying the lipid composition. In this review, highlighted are the recent advances in the emulsion-based gene carriers.


Principles of epidemiological modelling.
Epidemiological modelling can be a powerful tool to assist animal health policy development and disease prevention and control. Models can vary from simple deterministic mathematical models through to complex spatially-explicit stochastic simulations and decision support systems. The approach used will vary depending on the purpose of the study, how well the epidemiology of a disease is understood, the amount and quality of data available, and the background and experience of the modellers. Epidemiological models can be classified into various categories depending on their treatment of variability, chance and uncertainty (deterministic or stochastic), time (continuous or discrete intervals), space (non-spatial or spatial) and the structure of the population (homogenous or heterogeneous mixing). The increasing sophistication of computers, together with greater recognition of the importance of spatial elements in the spread and control of disease, mean that models which incorporate spatial components are becoming more important in epidemiological studies. Multidisciplinary approaches using a range of new technologies make it possible to build more sophisticated models of animal disease. New generation epidemiological models enable disease to be studied in the context of physical, economic, technological, health, media and political infrastructures. To be useful in policy development, models must be fit for purpose and appropriately verified and validated. This involves ensuring that the model is an adequate representation of the system under study and that its outputs are sufficiently accurate and precise for the intended purpose. Finally, models are just one tool for providing technical advice, and should not be considered in isolation from data from experimental and field studies.


DMSO containing ruthenium(ii) hydrazone complexes: in vitro evaluation of biomolecular interaction and anticancer activity.
Synthesis, spectral, electrochemical and single crystal X-ray diffraction data of a new series of DMSO containing bivalent ruthenium hydrazone complexes are presented. XRD data of two of the new complexes revealed an octahedral coordination around the ruthenium ion satisfied by NOS2Cl2 atoms. Electrochemical studies showed the metal centred, quasi-reversible, one-electron redox behaviour of the new complexes. The binding of these complexes with biomolecules such as calf thymus DNA (CT-DNA) and bovine serum albumin (BSA) protein investigated by different spectrophotometric methods revealed an intercalative mode of interaction. The in vitro cytotoxicity of these complexes evaluated by the MTT assay on a panel of cancer and normal cell lines indicated that the above complexes are more toxic to cancer cells with a few micromolar concentrations as the IC50 value, but are significantly less toxic to normal cell lines. The observed variations in the binding interactions and cytotoxicity of the complexes were attributed to the nature of the hydrazide moiety of the hydrazones that influences their biological activities.


History and symptom taking in contact lens fitting and aftercare.
To appraise history and symptom taking for contact lens consultations, to determine current practice and to make recommendations for best practice. The peer reviewed academic literature was reviewed and the results informed a survey completed by 256 eye care practitioners (ECPs) on their current practice and influences. The last eye-test date, last contact lens aftercare (for existing wearers) and reason for visit are key questions for most ECPs. Detailed use of contact lens questions are more commonly applied in aftercares than when refitting patients who have previously discontinued wear (87% vs 56% use), whereas questions on ocular and general history, medication and lifestyle were generally more commonly utilised for new patients than in aftercares (72% vs 50%). 75% of ECPs requested patients bring a list of their medication to appointments. Differential diagnosis questioning was thorough in most ECPs (87% of relevant questions asked). Attempts to optimise compliance included oral instruction (95% always) and written patient instructions (95% at least sometimes). Abbreviations were used by 39% of respondents (26% used ones provided by a professional body). There is scope for more consistency in history and symptom taking for contact lens consultations and recommendations are made.


Staphylococcus aureus CcpA affects virulence determinant production and antibiotic resistance.
Carbon catabolite protein A (CcpA) is known to function as a major regulator of gene expression in different gram-positive organisms. Deletion of the ccpA homologue (saCOL1786) in Staphylococcus aureus was found to affect growth, glucose metabolization, and transcription of selected virulence determinants. In liquid culture, deletion of CcpA decreased the growth rate and yield; however, the effect was only transient during the exponential-growth phase as long as glucose was present in the medium. Depletion of glucose and production of lactate was delayed, while the level of excretion of acetate was less affected and was even higher in the mutant culture. On solid medium, in contrast, growth of the DeltaccpA mutant resulted in smaller colonies containing a lower number of CFU per colony. Deletion of CcpA had an effect on the expression of important virulence factors of S. aureus by down-regulating RNAIII, the effector molecule of the agr locus, and altering the transcription patterns of hla, encoding alpha-hemolysin, and spa, encoding protein A. CcpA inactivation markedly reduced the oxacillin resistance levels in the highly methicillin-resistant S. aureus strain COLn and the teicoplanin resistance level in a glycopeptide-intermediate-resistant S. aureus strain. The presence of CcpA in the capsular polysaccharide serotype 5 (CP5)-producing strain Newman abolished capsule formation and decreased cap operon transcription in the presence of glucose. The staphylococcal CcpA thus not only is involved in the regulation of carbon metabolism but seems to function as a modulator of virulence gene expression as well.


Immunolocalization of the Nuk receptor tyrosine kinase suggests roles in segmental patterning of the brain and axonogenesis.
Neural kinase (Nuk) encodes a murine receptor-like tyrosine kinase belonging to the Eph/Elk/Eck family. Protein localization studies indicate that during early embryogenesis Nuk is confined to the developing nervous system, where it marks segments along the axis of the neural tube in the hindbrain (rhombomeres r2, r3 and r5) and specific morphological bulges of the midbrain and forebrain. Subcellular localization of Nuk indicates that this receptor is concentrated at sites of cell-cell contact, often involving migrating neuronal cells or their extensions. Most notably, high levels of Nuk protein are found within initial axon outgrowths and associated nerve fibers. The axonal localization of Nuk is transient and is not detected after migrations have ceased, suggesting a role for this tyrosine kinase during the early pathfinding and/or fasciculation stages of axonogenesis. The subcellular localization of Nuk, as well as the presence of fibronectin type III and immunoglobulin-like adhesive domains on the extracellular region, suggest this receptor tyrosine kinase may function to regulate specific cell-cell interactions during early development of the murine nervous system.


Reference-facilitated phosphoproteomics: fast and reliable phosphopeptide validation by microLC-ESI-Q-TOF MS/MS.
Recent advances in instrument control and enrichment procedures have enabled us to quantify large numbers of phosphoproteins and record site-specific phosphorylation events. An intriguing problem that has arisen with these advances is to accurately validate where phosphorylation events occur, if possible, in an automated manner. The problem is difficult because MS/MS spectra of phosphopeptides are generally more complicated than those of unmodified peptides. For large scale studies, the problem is even more evident because phosphorylation sites are based on single peptide identifications in contrast to protein identifications where at least two peptides from the same protein are required for identification. To address this problem we have developed an integrated strategy that increases the reliability and ease for phosphopeptide validation. We have developed an off-line titanium dioxide (TiO(2)) selective phosphopeptide enrichment procedure for crude cell lysates. Following enrichment, half of the phosphopeptide fractionated sample is enzymatically dephosphorylated, after which both samples are subjected to LC-MS/MS. From the resulting MS/MS analyses, the dephosphorylated peptide is used as a reference spectrum against the original phosphopeptide spectrum, in effect generating two peptide spectra for the same amino acid sequence, thereby enhancing the probability of a correct identification. The integrated procedure is summarized as follows: 1) enrichment for phosphopeptides by TiO(2) chromatography, 2) dephosphorylation of half the sample, 3) LC-MS/MS-based analysis of phosphopeptides and corresponding dephosphorylated peptides, 4) comparison of peptide elution profiles before and after dephosphorylation to confirm phosphorylation, and 5) comparison of MS/MS spectra before and after dephosphorylation to validate the phosphopeptide and its phosphorylation site. This phosphopeptide identification represents a major improvement as compared with identifications based only on single MS/MS spectra and probability-based database searches. We investigated an applicability of this method to crude cell lysates and demonstrate its application on the large scale analysis of phosphorylation sites in differentiating mouse myoblast cells.


Release of insulin from PLGA-alginate dressing stimulates regenerative healing of burn wounds in rats.
Burn wound healing involves a complex set of overlapping processes in an environment conducive to ischaemia, inflammation and infection costing $7.5 billion/year in the U.S.A. alone, in addition to the morbidity and mortality that occur when the burns are extensive. We previously showed that insulin, when topically applied to skin excision wounds, accelerates re-epithelialization and stimulates angiogenesis. More recently, we developed an alginate sponge dressing (ASD) containing insulin encapsulated in PLGA [poly(D,L-lactic-co-glycolic acid)] microparticles that provides a sustained release of bioactive insulin for >20 days in a moist and protective environment. We hypothesized that insulin-containing ASD accelerates burn healing and stimulates a more regenerative, less scarring healing. Using heat-induced burn injury in rats, we show that burns treated with dressings containing 0.04 mg insulin/cm(2) every 3 days for 9 days have faster closure, a higher rate of disintegration of dead tissue and decreased oxidative stress. In addition, in insulin-treated wounds, the pattern of neutrophil inflammatory response suggests faster clearing of the burned dead tissue. We also observe faster resolution of the pro-inflammatory macrophages. We also found that insulin stimulates collagen deposition and maturation with the fibres organized more like a basket weave (normal skin) than aligned and cross-linked (scar tissue). In summary, application of ASD-containing insulin-loaded PLGA particles on burns every 3 days stimulates faster and more regenerative healing. These results suggest insulin as a potential therapeutic agent in burn healing and, because of its long history of safe use in humans, insulin could become one of the treatments of choice when repair and regeneration are critical for proper tissue function.


Gene transfer of human Apoe isoforms results in differential modulation of amyloid deposition and neurotoxicity in mouse brain.
Inheritance of the ε4 allele of apolipoprotein E (APOE) is the strongest genetic risk factor associated with the sporadic form of Alzheimer's disease (AD), whereas the rare APOE ε2 allele has the opposite effect. However, the mechanisms whereby APOE confers risk and protection remain uncertain. We used a gene transfer approach to bathe the cortex of amyloid plaque-bearing transgenic mice with virally expressed human APOE. We monitored amyloid-β (Aβ) with multiphoton imaging, in vivo microdialysis, and postmortem array tomography to study the kinetics of human APOE-mediated changes in Aβ-related neurotoxicity in a mouse model of AD. We observed that human APOE4 increased the concentrations of oligomeric Aβ within the interstitial fluid and exacerbated plaque deposition; the converse occurred after exposure to human APOE2. Peri-plaque synapse loss and dystrophic neurites were also worsened by APOE4 or attenuated by APOE2. Egress of Aβ from the central nervous system (CNS) into the plasma was diminished by APOE3 and APOE4 compared to APOE2, in accord with isoform-specific retention of Aβ in the CNS. Overall, our data show a differential effect of human APOE isoforms on amyloid deposition and clearance in transgenic mice and, more importantly, on Aβ-mediated synaptotoxicity. These results suggest that the APOE genetic risk is mediated by Aβ, and that therapeutic approaches aimed at decreasing APOE4, or increasing APOE2, may be beneficial in AD.


Spectral properties of the prototropic forms of fluorescein in aqueous solution.
The commonly used fluorescent probe, fluorescein, can exist in seven prototropic forms. We have used global analysis procedures to reanalyze the absorption data of Diehl and Horchak-Morris (Talanta 34, 739-741, 1987) in terms of five alternative ionization models. We identify the forms of fluorescein present in aqueous solution and the pK a of each ionisation transition. The pKa values of the neutral xanthene, carboxylic acid, and cationic xanthene groups are 6.3, 3.1-3.4, and 3.1-3.4, respectively, and the pKa value of lactonization is 2.4. As a consequence, the neutral form of fluorescein is a mixture of the lactone (70%), zwitterionic (15%), and quinoid (15%) forms. A knowledge of the forms present in solution permits the characterization of their spectral properties. It is shown that the quinoid and monoanion forms have similar absorption spectra, while the zwitterion spectrum is similar to that of the cation but blue-shifted by 3 nm. The emission spectra of the monoanion and quinoid forms are also identified and shown to be similar but not identical. A model for the excited-state reactions of fluorescein is presented.


On the widespread enhancement in fine particulate matter across the Indo-Gangetic Plain towards winter.
Fine particulate matter (PM2.5, aerodynamic diameter ≤2.5 µm) impacts the climate, reduces visibility and severely influences human health. The Indo-Gangetic Plain (IGP), home to about one-seventh of the world's total population and a hotspot of aerosol loading, observes strong enhancements in the PM2.5 concentrations towards winter. We performed high-resolution (12 km × 12 km) atmospheric chemical transport modeling (WRF-Chem) for the post-monsoon to winter transition to unravel the underlying dynamics and influences of regional emissions over the region. Model, capturing the observed variations to an extent, reveals that the spatial distribution of PM2.5 having patches of enhanced concentrations (≥100 µgm-3) during post-monsoon, evolves dramatically into a widespread enhancement across the IGP region during winter. A sensitivity simulation, supported by satellite observations of fires, shows that biomass-burning emissions over the northwest IGP play a crucial role during post-monsoon. Whereas, in contrast, towards winter, a large-scale decline in the air temperature, significantly shallower atmospheric boundary layer, and weaker winds lead to stagnant conditions (ventilation coefficient lower by a factor of ~4) thereby confining the anthropogenic influences closer to the surface. Such changes in the controlling processes from post-monsoon to winter transition profoundly affect the composition of the fine aerosols over the IGP region. The study highlights the need to critically consider the distinct meteorological processes of west-to-east IGP and changes in dominant sources from post-monsoon to winter in the formulation of future pollution mitigation policies.


Treatment of cluster headache with topiramate: effects and side-effects in five patients.
We report on clinical experience with topiramate in the prophylactic treatment of three patients with chronic and two patients with episodic, otherwise therapy-resistant, cluster headache. Patients were treated with daily doses of 75-200 mg topiramate. Topiramate was effective in three patients but proved ineffective and also caused intolerable side-effects in two patients. Topiramate may have prophylactic properties for treating cluster headache at lower doses than needed in epilepsy therapy, but its clinical value is limited due to central nervous system side-effects.


Physiological role of the cellular prion protein.
The prion protein (PrP) plays a key role in the pathogenesis of prion diseases. However, the normal function of the protein remains unclear. The cellular isoform (PrP(C)) is expressed most abundantly in the brain, but has also been detected in other non-neuronal tissues as diverse as lymphoid cells, lung, heart, kidney, gastrointestinal tract, muscle, and mammary glands. Cell biological studies of PrP contribute to our understanding of PrP(C) function. Like other membrane proteins, PrP(C) is post-translationally processed in the endoplasmic reticulum and Golgi on its way to the cell surface after synthesis. Cell surface PrP(C) constitutively cycles between the plasma membrane and early endosomes via a clathrin-dependent mechanism, a pathway consistent with a suggested role for PrP(C) in cellular trafficking of copper ions. Although PrP(-/-) mice have been reported to have only minor alterations in immune function, PrP(C) is up-regulated in T cell activation and may be expressed at higher levels by specialized classes of lymphocytes. Furthermore, antibody cross-linking of surface PrP(C) modulates T cell activation and leads to rearrangements of lipid raft constituents and increased phosphorylation of signaling proteins. These findings appear to indicate an important but, as yet, ill-defined role in T cell function. Recent work has suggested that PrP(C) is required for self-renewal of haematopoietic stem cells. PrP(C) is highly expressed in the central nervous system, and since this is the major site of prion pathology, most interest has focused on defining the role of PrP(C) in neurones. Although PrP(-/-) mice have a grossly normal neurological phenotype, even when neuronal PrP(C) is knocked out postnatally, they do have subtle abnormalities in synaptic transmission, hippocampal morphology, circadian rhythms, and cognition and seizure threshold. Other postulated neuronal roles for PrP(C) include copper-binding, as an anti- and conversely, pro-apoptotic protein, as a signaling molecule, and in supporting neuronal morphology and adhesion. The prion protein may also function as a metal binding protein such as copper, yielding cellular antioxidant capacity suggesting a role in the oxidative stress homeostasis. Finally, recent observations on the role of PrP(C) in long-term memory open a challenging field.


Effects of sympathetic activation on ventricular ectopic beats in subjects with and without evidence of organic heart disease.
In a selected group of 10 apparently healthy subjects and 22 patients with organic heart disease, all with frequent ventricular ectopic beats on Holter monitoring, we assessed the influence of sympathetic activation by comparing the arrhythmogenic effects of a symptom-limited bicycle exercise stress test and 90 degree head up tilt. Tilting reduced ventricular arrhythmias in the normal subjects (-48 +/- 18% from 9 +/- 2 beats min-1, P less than 0.05). Exercise stress testing caused small and insignificant changes in arrhythmias during the early (50-75 W) phases and an almost complete suppression of ventricular ectopic beats in the final stages (-99 +/- 1%, P less than 0.01). In six of the 10 subjects, ventricular arrhythmias reappeared in the early recovery phase. In the 22 patients with organic heart disease, tilting increased ventricular ectopic beats (43 +/- 17% from 9 +/- 3 beats min-1, P less than 0.05); augmented repetitive forms in 12 patients (179 +/- 88% from 1.4 +/- 0.6 per 3 min) and produced repetitive forms in six of the 10 remaining patients who did not show repetitive forms during control conditions. Exercise stress testing caused a marked increase in ectopic activity in the early phase (84 +/- 35%) while the response during the maximal phase of exercise as well as during recovery was related to the effort capabilities. Arrhythmias were increased in 12 patients with limited exercise duration and were reduced in 10 patients with good exercise tolerance. These data indicate that sympathetic activation has different effects on ventricular arrhythmias depending on the clinical setting and that tilting is a useful maneuver to evaluate the arrhythmogenic effects of increased sympathetic activity.


Avirulence in the wheat septoria tritici leaf blotch fungus Mycosphaerella graminicola is controlled by a single locus.
Segregation of avirulence in Mycosphaerella graminicola, a heterothallic ascomycete that causes wheat septoria tritici leaf blotch, was studied in F1, BC1, and F2 populations by inoculation assays on five wheat cultivars in the seedling stage and by amplified fragment length polymorphism and random amplified polymorphic DNA analyses. F1 was generated by crossing isolates IPO323 (avirulent) and IPO94269 (virulent). All F1, BC1, and F2 progeny isolates were virulent on the susceptible check cultivar Taichung 29 and were avirulent on the resistant check cultivar Kavkav-K4500. Avirulence segregation was observed in F1 and in several BC1 and F2 generations on the differential cultivars Shafir, Kavkaz, and Veranopolis at a 1:1 ratio. Avirulence for the three differential cultivars always cosegregated. We conclude that avirulence in isolate IPO323 is controlled by a single, seemingly complex locus.


Oral zinc for the common cold.
Is oral zinc associated with a shorter duration, decreased severity, and reduced incidence of the common cold compared with placebo? When initiated within 24 hours of symptom onset, oral zinc is associated with a shorter duration of the common cold in healthy people. However, there is no association between oral zinc and symptom severity, and the prevalence of adverse effects with zinc lozenges is high. Given the high heterogeneity of data, these results should be interpreted with caution. Used prophylactically, oral zinc is associated with a reduced cold incidence in children. Prophylactic use has not been studied in adults.


Staphylococcus aureus enterotoxins A- and B: binding to the enterocyte brush border and uptake by perturbation of the apical endocytic membrane traffic.
Enterotoxins of Staphylococcus aureus are among the most common causes of food poisoning. Acting as superantigens they intoxicate the organism by causing a massive uncontrolled T cell activation that ultimately may lead to toxic shock and death. In contrast to our detailed knowledge regarding their interaction with the immune system, little is known about how they penetrate the epithelial barrier to gain access to their targets. We therefore studied the uptake of two staphylococcal enterotoxins (SEs), SEA and SEB, using organ cultured porcine jejunal explants as model system. Attachment of both toxins to the villus surface was scarce and patchy compared with that of cholera toxin B (CTB). SEA and SEB also bound to microvillus membrane vesicles in vitro, but less efficiently than CTB, and the binding was sensitive to treatment with endoglycoceramidase II, indicating that a glycolipid, possibly digalactosylceramide, acts as cell surface receptor at the brush border. Both SEs partitioned poorly with detergent resistant membranes (DRMs) of the microvillus, suggesting a weak association with lipid raft microdomains. Where attachment occurred, cellular uptake of SEA and SEB was also observed. In enterocytes, constitutive apical endocytosis normally proceeds only to subapical early endosomes present in the actomyosin-rich "terminal web" region. But, like CTB, both SEA and SEB penetrated deep into the cytoplasm. In conclusion, the data show that after binding to the enterocyte brush border SEA and SEB perturb the apical membrane trafficking, enabling them to engage in transcytosis to reach their target cells in the subepithelial lamina propria.


Blastocystis subtyping and its association with intestinal parasites in children from different geographical regions of Colombia.
Blastocystis is a common enteric protist colonizing probably more than 1 billion people with a large variety of non-human hosts. Remarkable genetic diversity has been observed, leading to the subdivision of the genus into multiple subtypes (ST), some of which are exclusively found in non-human hosts. The aim of this study was to determine the distribution of Blastocystis STs/18S alleles in symptomatic (abdominal pain, anal pruritus, diarrhea, headache, nauseas and/or vomit) and asymptomatic children from nine geographical regions of Colombia. A total of 2026 fecal samples were collected as part of a national survey to estimate the frequency of intestinal parasites in children. A set of 256 samples that were Blastocystis positive was finally selected. The samples were submitted to DNA extraction, Real Time PCR and sequencing using Blastocystis-specific primers targeting the small subunit rRNA gene for ST identification. DNA of Ascaris lumbricoides (16.4%), Trichuris trichiura (8.2%), hookworms (Necator americanus/Ancylostoma duodenale) (7.3%), Giardia duodenalis (23.1%), Entamoeba complex (82%), Entamoeba coli (55%), Hymenolepis nana (0.8%), Endolimax nana (33.2%) and Neobalantidium coli (2.7%) was detected in the Blastocystis-positive samples. We detected ST1 (21.4%), ST2 (19.5%), ST3 (55.5%), ST4 (0.8%), ST6 (2%) and ST7 (0.8%); alleles 1, 2, 4, 81, 82 and 83 for ST1; alleles 9, 11, 12, 15, 67, 71 and 73 for ST2; alleles 34, 36, 38, 45, 49, 55, 134 and 128 for ST3; allele 42 for ST4; allele 122 for ST6, and allele 142 for ST7. Further studies implementing high-resolution molecular markers are necessary to understand the dynamics of Blastocystis transmission and the role of this Stramenopila in health and disease.


Hydrops fetalis and pulmonary lymphangiectasia due to FOXC2 mutation: an autosomal dominant hereditary lymphedema syndrome with variable expression.
Non-immune hydrops fetalis may find its origin within genetically determined lymphedema syndromes, caused by mutations in FOXC2 and SOX-18. We describe a newborn girl, diagnosed with non-immune hydrops fetalis at a gestational age of 30 weeks. Family history revealed the presence of an autosomal dominant late-onset form of lymphedema of the lower limbs in her father, associated with an aberrant implantation of the eyelashes in some individuals. The newborn, hydropic girl suffered from severe pulmonary lymphangiectasia, resulting in terminal respiratory failure at the age of 3 months. Genetic analysis in both the father and the newborn girl demonstrated a heterozygous FOXC2 mutation, i.e., c.939C>A, p.Tyr313X. Her two older sisters are currently asymptomatic and the parents decided not to test them for the FOXC2 mutation. Patients with a mutation in the FOXC2 transcription factor usually show lower limb lymphedema with onset at or after puberty, together with distichiasis. However, the eye manifestations can be very mild and easily overlooked. The association between FOXC2 mutation and neonatal hydrops resulting in terminal respiratory failure is not reported so far. Therefore, in sporadic patients diagnosed with non-immune hydrops fetalis, lymphangiogenic genes should be systematically screened for mutations. In addition, all cases of fetal edema must prompt a thorough analysis of the familial pedigree, in order to detect familial patterns and to facilitate adequate antenatal counseling.


Skin toxicity evaluation protocol with panitumumab (STEPP), a phase II, open-label, randomized trial evaluating the impact of a pre-Emptive Skin treatment regimen on skin toxicities and quality of life in patients with metastatic colorectal cancer.
Panitumumab, a fully human monoclonal antibody targeting the epidermal growth factor receptor (EGFR), is approved in the United States and Europe for the treatment of refractory metastatic colorectal cancer (mCRC). Skin toxicities are the most common adverse events with EGFR inhibitors. This is the first study designed to examine differences between pre-emptive and reactive skin treatment for specific skin toxicities in patients with mCRC for any EGFR inhibitor. Patients receiving panitumumab-containing therapy were randomly assigned 1:1 to pre-emptive or reactive treatment (after skin toxicity developed). Pre-emptive treatment included use of skin moisturizers, sunscreen, topical steroid, and doxycycline. The primary end point of the study was the incidence of protocol-specified >or= grade 2 skin toxicities during the 6-week skin treatment period. Quality of life (QOL) was assessed with the Dermatology Life Quality Index (DLQI). Of 95 enrolled patients, 48 received pre-emptive treatment, and 47 received reactive treatment. The incidence of protocol-specified >or= grade 2 skin toxicities during the 6-week skin treatment period was 29% and 62% for the pre-emptive and reactive groups, respectively. Mean DLQI score change from baseline to week 3 was 1.3 points and 4.2 points in the pre-emptive and reactive groups, respectively. The pre-emptive skin treatment regimen was well tolerated. The incidence of specific >or= grade 2 skin toxicities during the 6-week skin treatment period was reduced by more than 50% in the pre-emptive group compared with the reactive group. Patients in the pre-emptive group reported less QOL impairment than patients in the reactive group.


Prognostic indicators in patients with intracranial tuberculoma: a review of 102 cases.
To see the characteristics, course and outcome of patients suffering from intracranial tuberculoma. Retrospective review of 102 patients diagnosed as intracranial tuberculoma at a tertiary care center over 10 years. A total of 102 cases were seen with an age range of 1 to 75 years (mean, 30 years). Predisposing factors included Diabetes mellitus (8 patients) and pregnancy or puerperium (7 patients). Five pediatric patients had tuberculoma despite documented BCG vaccination. Fever (59%), headache (57%), meningeal irritation (36%) were the commonest presenting features; one-third of patients were drowsy or comatosed at presentation. Cerebrospinal fluid analysis was performed in 63 patients, of whom 88% had elevated protein, 83% had low glucose, and 84% had pleocytosis (one-third with neutrophilia). Forty-nine (50%) patients had clinical or laboratory evidence of concomitant tuberculous meningitis. Chest radiographs showed active or old tuberculous infection (25%), with a miliary pattern in 20%. Two-thirds of subjects had multiple tuberculomas (mean, 4.5 lesions per patient) on contrast CT or MRI scan. Hydrocephalus was present in 37 (37%) patients of which 21 required shunt surgery. Thirty-nine patients had > 9 months of follow up; 17 patients showed complete recovery, 20 patients had partial recovery, and 2 patients had no response. Coma at presentation and miliary pattern on chest X-ray were predictors of poor prognosis. The study demonstrate that fever, headache, signs of meningeal irritation and cranial nerve palsies are common presenting features. Complete recovery was seen in 40% patients. Coma and military TB are predictors of poor prognosis.