Predation-driven dynamics of zooplankton and phytoplankton communities in a whole-lake experiment.
1. Species compositions of zooplankton and phytoplankton were followed in Tuesday Lake before and after experimental manipulation of its fish populations (addition of piscivorous largemouth bass, removal of planktivorous minnows). Plankton dynamics were compared to those of adjacent, unmanipulated Paul Lake, where piscivorous fish have been dominant historically. 2. Indices of similarity for the zooplankton communities in the two lakes in 1984 prior to the manipulation were low; however, following the manipulation in spring, 1985, similarity of the zooplankton in the two lakes rose considerably and remained high throughout 1986. This was the result of an increase in Tuesday Lake of previously rare large-bodied cladocerans (Daphnia pulex, Holopedium gibberum) which were the dominants in Paul Lake, and the disappearance in Tuesday Lake of the dominant small-bodied copepod Tropocyclops prasinus, a minor component of the Paul Lake zooplankton. These observations are consistent with prior observations of the effects of size-selective predation on zooplankton communities. 3. Phytoplankton communities also responded strongly to the manipulation, with similarity indices for the two lakes rising from low levels in 1984 to high levels of similarity in 1985 and 1986, reflecting the decrease of formerly dominant Tuesday Lake taxa which were unimportant in Paul Lake and the appearance or increase in Tuesday Lake of several taxa characteristic of the Paul Lake phytoplankton assemblage. these results clearly show that food web structure can have pronounced effects on community composition at all levels of the food web, and that, just as zooplankton communities are structured by sizeselective predation, phytoplankton communities are structured by herbivory. These observations may provide some insight into factors governing the complex distributions of phytoplankton species among various lakes.


Mechanistic Studies of Ethylene and α-Olefin Co-oligomerization Catalyzed by Chromium-PNP Complexes.
To explore the possibility of producing a narrow distribution of mid- to long-chain hydrocarbons from ethylene as a chemical feedstock, co-oligomerization of ethylene and linear α-olefins (LAOs) was investigated, using a previously reported chromium complex, [CrCl(3)(PNP(OMe))] (1, where PNP(OMe) = N,N-bis(bis(o-methoxyphenyl)phosphino)methylamine). Activation of 1 by treatment with modified methylaluminoxane (MMAO) in the presence of ethylene and 1-hexene afforded mostly C(6) and C(10) alkene products. The identities of the C(10) isomers, assigned by detailed gas chromatographic and mass spectrometric analyses, strongly support a mechanism that involves five- and seven-membered metallacyclic intermediates comprising of ethylene and LAO units. Using 1-heptene as a mechanistic probe, it was established that 1-hexene formation from ethylene is competitive with formation of ethylene/LAO co-trimers, and that co-trimers derived from one ethylene and two LAO molecules are also generated. Complex 1/MMAO is also capable of converting 1-hexene to C(12) dimers and C(18) trimers, albeit with poor efficiency. The mechanistic implications of these studies are discussed and compared to previous reports of olefin co-trimerization.


Morphology and immunoreactivity of retrogradely double-labeled ganglion cells in the mouse retina.
To examine the specificity and reliability of a retrograde double-labeling technique that was recently established for identification of retinal ganglion cells (GCs) and to characterize the morphology of displaced (d)GCs (dGs). A mixture of the gap-junction-impermeable dye Lucifer yellow (LY) and the permeable dye neurobiotin (NB) was applied to the optic nerve stump for retrograde labeling of GCs and the cells coupled with them. A confocal microscope was adopted for morphologic observation. GCs were identified by LY labeling, and they were all clearly labeled by NB. Cells coupled to GCs contained a weak NB signal but no LY. LY and NB revealed axon bundles, somas and dendrites of GCs. The retrogradely identified GCs numbered approximately 50,000 per retina, and they constituted 44% of the total neurons in the ganglion cell layer (GCL). Somas of retrogradely identified dGs were usually negative for glycine, ChAT (choline acetyltransferase), bNOS (brain-type nitric oxidase), GAD (glutamate decarboxylase), and glial markers, and occasionally, they were weakly GABA-positive. dGs averaged 760 per retina and composed 1.7% of total GCs. Sixteen morphologic subtypes of dGs were encountered, three of which were distinct from known GCs. dGs sent dendrites to either sublaminas of the IPL, mostly sublamina a. The retrograde labeling is reliable for identification of GCs. dGs participate in ON and OFF light pathways but favor the OFF pathway. ChAT, bNOS, glycine, and GAD remain reliable AC markers in the GCL. GCs may couple to GABAergic ACs, and the gap junctions likely pass NB and GABA.


The motivational dynamics of retrieval-induced forgetting: a test of cognitive energetics theory.
Two experiments addressed the phenomenon of retrieval-induced forgetting (RIF) from the standpoint of cognitive energetics theory (CET). Consistent with the inhibitory account of RIF and with the notion that inhibition can be demanding and resource dependent, we found that where the inhibitory activity was difficult (vs. easy), defining a high restraining force according to the CET, RIF occurred only in the presence of a high driving force combining an elevated motivation to inhibit with the availability of high resources. Overall, the current work highlights the crucial role of motivation in producing the RIF and the way in which this phenomenon abides by the general principles of motivated cognition.


Lilly lecture 1983. Abnormal products of the human insulin gene.
Heritable abnormalities in the insulin gene have often been considered in terms of their potential for contributing to diabetes. It is only within the last 5 yr, however, that evidence has demonstrated the existence of insulin gene mutations in man and the secretion of abnormal human insulins in affected individuals. HPLC analysis of insulin purified from serum by immuno-affinity chromatography and detection of insulin by radioimmunoassay have documented abnormal insulins in subjects from three separate families. HPLC analysis of these natural insulins and of semisynthetic insulin analogues have identified the accompanying amino acid substitutions in two of these cases: in one, leucine replaces phenylalanine B25; in the other, serine replaces phenylalanine B24. Both substitutions occur in an invariant tetrapeptide sequence within the active site of the hormone. Studies of the biologic activities of these analogues further suggest that replacements at position B25 result in the loss of an important side chain contact between the hormone and its receptor, whereas those at position B24 result in conformational changes in the insulin molecule as a whole. Two additional individuals have been identified to secrete abnormal intermediates of proinsulin conversion in which the C-peptide remains attached to the insulin A-chain and in which Arg65 has been replaced by a nonbasic amino acid. This result emphasizes the importance of dibasic amino acid pairs at prohormone conversion sites and provides clues about the evolution of hormone precursors. Thus, studies of the products of abnormal human insulin genes have provided insights into subjects as varied as insulin biosynthesis, structure-activity relationships in insulin recognition by receptors, and the physiology of insulin action.


Seeking Genomic Knowledge: The Case for Clinical Restraint.
Genome sequencing technology provides new and promising tests for clinical practice, including whole genome sequencing, which measures an individual's complete DNA sequence, and whole exome sequencing, which measures the DNA for all genes coding for proteins. These technologies make it possible to test for multiple genes in a single test, which increases the efficiency of genetic testing. However, they can also produce large amounts of information that cannot be interpreted or is of limited clinical utility. This additional information could be distracting for patients and clinicians, and contribute to unnecessary healthcare costs. The potential for genomic sequencing to improve care will be context-dependent, varying for different patients and clinical settings. This Article argues that a disciplined approach is needed, incorporating research to assess when and how genomic information can improve clinical outcomes, practice guidelines that direct optimal uses of genomic sequencing, and efforts to limit the production of genomic information unrelated to the clinical needs of the patient. Without this approach, genomic testing could add to current unsustainable healthcare costs and prove unaffordable in the long run.


An optimized blockwise nonlocal means denoising filter for 3-D magnetic resonance images.
A critical issue in image restoration is the problem of noise removal while keeping the integrity of relevant image information. Denoising is a crucial step to increase image quality and to improve the performance of all the tasks needed for quantitative imaging analysis. The method proposed in this paper is based on a 3-D optimized blockwise version of the nonlocal (NL)-means filter (Buades, et al., 2005). The NL-means filter uses the redundancy of information in the image under study to remove the noise. The performance of the NL-means filter has been already demonstrated for 2-D images, but reducing the computational burden is a critical aspect to extend the method to 3-D images. To overcome this problem, we propose improvements to reduce the computational complexity. These different improvements allow to drastically divide the computational time while preserving the performances of the NL-means filter. A fully automated and optimized version of the NL-means filter is then presented. Our contributions to the NL-means filter are: 1) an automatic tuning of the smoothing parameter; 2) a selection of the most relevant voxels; 3) a blockwise implementation; and 4) a parallelized computation. Quantitative validation was carried out on synthetic datasets generated with BrainWeb (Collins, et al., 1998). The results show that our optimized NL-means filter outperforms the classical implementation of the NL-means filter, as well as two other classical denoising methods [anisotropic diffusion (Perona and Malik, 1990)] and total variation minimization process (Rudin, et al., 1992) in terms of accuracy (measured by the peak signal-to-noise ratio) with low computation time. Finally, qualitative results on real data are presented .


Plant community feedbacks and long-term ecosystem responses to multi-factored global change.
While short-term plant responses to global change are driven by physiological mechanisms, which are represented relatively well by models, long-term ecosystem responses to global change may be determined by shifts in plant community structure resulting from other ecological phenomena such as interspecific interactions, which are represented poorly by models. In single-factor scenarios, plant communities often adjust to increase ecosystem response to that factor. For instance, some early global change experiments showed that elevated CO2 favours plants that respond strongly to elevated CO2, generally amplifying the response of ecosystem productivity to elevated CO2, a positive community feedback. However, most ecosystems are subject to multiple drivers of change, which can complicate the community feedback effect in ways that are more difficult to generalize. Recent studies have shown that (i) shifts in plant community structure cannot be reliably predicted from short-term plant physiological response to global change and (ii) that the ecosystem response to multi-factored change is commonly less than the sum of its parts. Here, we survey results from long-term field manipulations to examine the role community shifts may play in explaining these common findings. We use a simple model to examine the potential importance of community shifts in governing ecosystem response. Empirical evidence and the model demonstrate that with multi-factored change, the ecosystem response depends on community feedbacks, and that the magnitude of ecosystem response will depend on the relationship between plant response to one factor and plant response to another factor. Tradeoffs in the ability of plants to respond positively to, or to tolerate, different global change drivers may underlie generalizable patterns of covariance in responses to different drivers of change across plant taxa. Mechanistic understanding of these patterns will help predict the community feedbacks that determine long-term ecosystem responses.


Childhood physical activity body contact risk: feasibility of a novel technique for objective measurements of impact speed, frequency, and intentionality.
Children at risk for bleeding injuries are restricted from body contact during physical activity but current recommendations are based on expert opinion. Evaluate high-speed digital video recording as an objective measure of body contact risk during physical activity. Observational study of physical activities among healthy children, grouped according to participation in teams (vs. individual) and on their perceived risk of injury (high/low). High speed digital video recordings documented the collision target (floor/ground/ice, people, wall, equipment), estimated speed, and impact rates for team and individual activities, with and without expected body contact. Among 348 participating children (3-16 years, 51% female), 32% to 78% experienced at least one contact. Impact type varied significantly (chi-square, p < 0.001) by activity category. Unstructured and Team high risk activity impacts were primarily with the floor/ground, whereas Individual low risk activities were characterized by equipment impacts. Impact speeds were typically 1.0 to 2.1 m s(-1) . Higher impact speeds occurred during instructional classes (2.1 m s(-1) ), unstructured free swim (1.9 m s(-1) ) and ball hockey (1.7 m s(-1) ). Impact rates were higher during Team high risk and Team low risk sports (3.0 and 1.8 impacts per minute, respectively) compared to Individual (high or low risk) or Unstructured activities (0.2-0.3 impacts per minute). High speed video recordings of childhood physical activity are a feasible method for characterizing the frequency, type, direction and speed of impacts. Quantifying the impacts that occur during childhood physical activity could inform the guidelines for physical activity participation among children with identified bleeding risks.


End-processing during non-homologous end-joining: a role for exonuclease 1.
Non-homologous end-joining (NHEJ) is a critical error-prone pathway of double strand break repair. We recently showed that tyrosyl DNA phosphodiesterase 1 (Tdp1) regulates the accuracy of NHEJ repair junction formation in yeast. We assessed the role of other enzymes in the accuracy of junction formation using a plasmid repair assay. We found that exonuclease 1 (Exo1) is important in assuring accurate junction formation during NHEJ. Like tdp1Δ mutants, exo1Δ yeast cells repairing plasmids with 5'-extensions can produce repair junctions with templated insertions. We also found that exo1Δ mutants have a reduced median size of deletions when joining DNA with blunt ends. Surprisingly, exo1Δ pol4Δ mutants repair blunt ends with a very low frequency of deletions. This result suggests that there are multiple pathways that process blunt ends prior to end-joining. We propose that Exo1 acts at a late stage in end-processing during NHEJ. Exo1 can reverse nucleotide additions occurring due to polymerization, and may also be important for processing ends to expose microhomologies needed for NHEJ. We propose that accurate joining is controlled at two steps, a first step that blocks modification of DNA ends, which requires Tdp1, and a second step that occurs after synapsis that requires Exo1.


Security optical data storage in Fourier holograms.
We have proposed and demonstrated a holographic security storage system that is implemented with a shift multiplexing technique. The security function of this storage system is achieved by using a microdiffuser (MD) for random phase encoding of the reference beams. The apparatus of random phase encoding in this system offers an additional and flexible function during the recording processes. The system can generate holographic security memory or nonsecurity holographic memory via using the MD or not. The storage capacity and the average signal-to-noise value of the security storage system are 16 bits/μm(2) and 3.5, respectively. Lateral shifting selectivity in this holographic security storage system is theoretically analyzed and experimentally investigated.


Application of the fractional Fourier transformation to digital holography recorded by an elliptical, astigmatic Gaussian beam.
The authors have studied the diffraction pattern produced by a particle field illuminated by an elliptic and astigmatic Gaussian beam. They demonstrate that the bidimensional fractional Fourier transformation is a mathematically suitable tool to analyse the diffraction pattern generated not only by a collimated plane wave [J. Opt. Soc. Am A 19, 1537 (2002)], but also by an elliptic and astigmatic Gaussian beam when two different fractional orders are considered. Simulations and experimental results are presented.


Second harmonic imaging and scoring of collagen in fibrotic tissues.
We compare second harmonic generation (SHG) to histological and immunohistochemical techniques for the visualization and scoring of collagen in biological tissues. We show that SHG microscopy is highly specific for fibrillar collagens and that combined SHG and two-photon excited fluorescence (2PEF) imaging can provide simultaneous three-dimensional visualization of collagen synthesis and assembly sites in transgenic animal models expressing GFP constructs. Finally, we propose several scores for characterizing collagen accumulation based on SHG images and appropriate for different types of collagen distributions. We illustrate the sensitivity of these scores in a murine model of renal fibrosis using a morphological segmentation of the tissue based on endogenous 2PEF signals.


The role of platelet activation in tumor metastasis.
Platelets are highly reactive components of the circulatory system, which exert not only haemostatic activity but also contribute to the modulation of various pathological conditions including inflammation, atherosclerosis and cancer metastasis through the release of cytokines, chemokines and the presentation of several adhesion molecules. During cancer metastasis, the formation of platelet-tumor cell aggregates in the circulation facilitates immune evasion and the microvascular arrest of tumor cells at distant sites. Several adhesion molecules, such as integrins and glycoproteins, were shown to be involved in this process. Recent findings indicate that P-selectin is another main mediator of platelet-tumor cell interactions. Other effects of activated platelets on cancer progression are associated with a release of platelet-derived factors stimulating tumor growth and angiogenesis. Any interference in platelet-tumor cell interactions resulted in attenuation of cancer metastasis. The well recognized, albeit not fully characterized function of platelets during cancer progression defines platelets as potential targets for cancer therapy. Specifically, the rapid expression of P-selectin on the cell surface of activated platelets and its strong association with metastasis provide a rationale for P-selectin inhibition as an antimetastatic treatment.


Diagnosing intramammary infections: evaluation of definitions based on a single milk sample.
Criteria for diagnosing intramammary infections (IMI) have been debated for many years. Factors that may be considered in making a diagnosis include the organism of interest being found on culture, the number of colonies isolated, whether or not the organism was recovered in pure or mixed culture, and whether or not concurrent evidence of inflammation existed (often measured by somatic cell count). However, research using these criteria has been hampered by the lack of a "gold standard" test (i.e., a perfect test against which the criteria can be evaluated) and the need for very large data sets of culture results to have sufficient numbers of quarters with infections with a variety of organisms. This manuscript used 2 large data sets of culture results to evaluate several definitions (sets of criteria) for classifying a quarter as having, or not having an IMI by comparing the results from a single culture to a gold standard diagnosis based on a set of 3 milk samples. The first consisted of 38,376 milk samples from which 25,886 triplicate sets of milk samples taken 1 wk apart were extracted. The second consisted of 784 quarters that were classified as infected or not based on a set of 3 milk samples collected at 2-d intervals. From these quarters, a total of 3,136 additional samples were evaluated. A total of 12 definitions (named A to L) based on combinations of the number of colonies isolated, whether or not the organism was recovered in pure or mixed culture, and the somatic cell count were evaluated for each organism (or group of organisms) with sufficient data. The sensitivity (ability of a definition to detect IMI) and the specificity (Sp; ability of a definition to correctly classify noninfected quarters) were both computed. For all species, except Staphylococcus aureus, the sensitivity of all definitions was <90% (and in many cases<50%). Consequently, if identifying as many existing infections as possible is important, then the criteria for considering a quarter positive should be a single colony (from a 0.01-mL milk sample) isolated (definition A). With the exception of "any organism" and coagulase-negative staphylococci, all Sp estimates were over 94% in the daily data and over 97% in the weekly data, suggesting that for most species, definition A may be acceptable. For coagulase-negative staphylococci, definitions B (2 colonies from a 0.01-mL milk sample) raised the Sp to 92 and 95% in the daily and weekly data, respectively. For "any organism," using definition B raised the Sp to 88 and 93% in the 2 data sets, respectively. The final choice of definition will depend on the objectives of study or control program for which the sample was collected.


Long-term safety and effectiveness of lubiprostone, a chloride channel (ClC-2) activator, in patients with chronic idiopathic constipation.
Lubiprostone helps relieve constipation in short-term 4-week studies. There are limited data on long-term pharmacological treatment with lubiprostone for chronic idiopathic constipation. To examine the long-term safety and effectiveness of lubiprostone in patients with chronic idiopathic constipation. In this prospective, multicenter, open-labeled trial, 248 patients aged ≥18 years with chronic idiopathic constipation were directed to take lubiprostone 24 mcg BID as needed for 48 weeks. Patients were allowed to decrease the dose in response to the perceived severity of constipation and need for relief. Hematology and chemistry profiles and assessment of constipation symptoms and its severity were performed at all visits. Adverse events (AEs) were recorded. Of the 248 patients who entered the trial, 127 (51%) completed the trial. A dose reduction was observed in 17% of the patients, resulting in an average study medication exposure across the study of approximately 1.7 capsules (or approximately 40.8 mcg) per day. The most common treatment-related AEs were nausea (19.8%), diarrhea (9.7%), abdominal distension (6.9%), headache (6.9%), and abdominal pain (5.2%). No deaths were reported and of the 16 reported serious AEs, one was considered possibly treatment related. Average changes in serum electrolytes were not clinically relevant at any time point during the study. On average, lubiprostone significantly (p < 0.0001) reduced patient-reported constipation severity, abdominal bloating, and abdominal discomfort across 48 weeks when compared to baseline. During this 48-week open-label study, lubiprostone was well tolerated. Bowel symptoms consistently improved over 48 weeks in adult patients with chronic idiopathic constipation.


De Garengeot's hernia: a case of acute appendicitis in a femoral hernia sac.
The presence of an appendix vermiformis in a femoral hernia sac is called De Garengeot's hernia. It is a very rare clinical condition and requires emergency surgery. However, preoperative diagnosis of De Garengeot's hernia is difficult. Herein, we report a 58-year-old female who presented with sudden-onset painful swelling in the right groin region. Diagnosis was established based on computed tomography findings, and appendectomy with mesh-free hernia repair was performed. The postoperative period was uneventful, and the histopathologic examination of the specimen revealed gangrenous appendicitis.


Changes in binge drinking and related problems among American college students between 1993 and 1997. Results of the Harvard School of Public Health College Alcohol Study.
In 1997, the Harvard School of Public Health College Alcohol Study resurveyed colleges that participated in a 1993 study. The findings revealed little change in binge drinking: a slight decrease in percentage of binge drinkers and slight increases in percentages of abstainers and frequent binge drinkers. Two of 5 students were binge drinkers (42.7%); 1 in 5 (19.0%) was an abstainer, and 1 in 5 was a frequent binge drinker (20.7%). As was true in 1993, 4 of 5 residents of fraternities or sororities were binge drinkers (81.1%). Asian students showed a greater increase and White students a greater decrease in binge drinking from 1993 to 1997, compared with all other students. Among students who drank alcohol, increases in frequency of drinking; drunkenness; drinking to get drunk; and alcohol-related problems, including drinking and driving, were reported. Binge drinkers in both 1993 and 1997 were at increased risk of alcohol-related problems, and nonbingers at colleges with high binge drinking rates had increased risks of encountering secondhand effects of binge drinking.


Absence of mouse 2B4 promotes NK cell-mediated killing of activated CD8+ T cells, leading to prolonged viral persistence and altered pathogenesis.
Persistent viral infections are often associated with inefficient T cell responses and sustained high-level expression of inhibitory receptors, such as the NK cell receptor 2B4 (also known as CD244), on virus-specific T cells. However, the role of 2B4 in T cell dysfunction is undefined, and it is unknown whether NK cells contribute to regulation of these processes. We show here that persistent lymphocytic choriomeningitis virus (LCMV) infection of mice lacking 2B4 resulted in diminished LCMV-specific CD8+ T cell responses, prolonged viral persistence, and spleen and thymic pathologies that differed from those observed in infected wild-type mice. Surprisingly, these altered phenotypes were not caused by 2B4 deficiency in T cells. Rather, the entire and long-lasting pathology and viral persistence were regulated by 2B4-deficient NK cells acting early in infection. In the absence of 2B4, NK cells lysed activated (defined as CD44hi) but not naive (defined as CD44lo) CD8+ T cells in a perforin-dependent manner in vitro and in vivo. These results illustrate the importance of NK cell self-tolerance to activated CD8+ T cells and demonstrate how an apparent T cell-associated persistent infection can actually be regulated by NK cells.


Reduced ventricular proliferation in the foetal cortex following maternal inflammation in the mouse.
It has been well established that maternal inflammation during pregnancy alters neurological function in the offspring, but its impact on cortical development and long-term consequences on the cytoarchitecture is largely unstudied. Here we report that lipopolysaccharide-induced systemic maternal inflammation in C57Bl/6 mice at embryonic Day 13.5 of pregnancy, as early as 8 h after challenge, caused a significant reduction in cell proliferation in the ventricular zone of the developing cerebral cortex, as revealed by quantification of anti-phospho-Histone H3 immunoreactivity and bromodeoxyuridine pulse labelling. The angle of mitotic cleavage, determined from analysis of haematoxylin and eosin staining, cyclin E1 gene expression and the pattern of β-catenin immunoreactivity were also altered by the challenge, which suggests a change from symmetric to asymmetric division in the radial progenitor cells. Modifications of cortical lamination and gene expression patterns were detected at post-natal Day 8 suggesting prolonged consequences of these alterations during embryonic development. Cellular uptake of proteins from the cerebrospinal fluid was observed in brains from lipopolysaccharide-treated animals in radial progenitor cells. However, the foetal blood-brain barrier to plasma proteins remained intact. Together, these results indicate that maternal inflammation can disrupt the ventricular surface and lead to decreased cellular proliferation. Changes in cell density in Layers IV and V at post-natal Day 8 show that these initial changes have prolonged effects on cortical organization. The possible shift in the fate of progeny and the resulting alterations in the relative cell numbers in the cerebral cortex following a maternal inflammatory response shown here will require further investigation to determine the long-term consequences of inflammation on the development of neuronal circuitry and behaviour.


Deep-Learning for Epicardial Adipose Tissue Assessment With Computed Tomography: Implications for Cardiovascular Risk Prediction.
Epicardial adipose tissue (EAT) volume is a marker of visceral obesity that can be measured in coronary computed tomography angiograms (CCTA). The clinical value of integrating this measurement in routine CCTA interpretation has not been documented. This study sought to develop a deep-learning network for automated quantification of EAT volume from CCTA, test it in patients who are technically challenging, and validate its prognostic value in routine clinical care. The deep-learning network was trained and validated to autosegment EAT volume in 3,720 CCTA scans from the ORFAN (Oxford Risk Factors and Noninvasive Imaging Study) cohort. The model was tested in patients with challenging anatomy and scan artifacts and applied to a longitudinal cohort of 253 patients post-cardiac surgery and 1,558 patients from the SCOT-HEART (Scottish Computed Tomography of the Heart) Trial, to investigate its prognostic value. External validation of the deep-learning network yielded a concordance correlation coefficient of 0.970 for machine vs human. EAT volume was associated with coronary artery disease (odds ratio [OR] per SD increase in EAT volume: 1.13 [95% CI: 1.04-1.30]; P = 0.01), and atrial fibrillation (OR: 1.25 [95% CI: 1.08-1.40]; P = 0.03), after correction for risk factors (including body mass index). EAT volume predicted all-cause mortality (HR per SD: 1.28 [95% CI: 1.10-1.37]; P = 0.02), myocardial infarction (HR: 1.26 [95% CI:1.09-1.38]; P = 0.001), and stroke (HR: 1.20 [95% CI: 1.09-1.38]; P = 0.02) independently of risk factors in SCOT-HEART (5-year follow-up). It also predicted in-hospital (HR: 2.67 [95% CI: 1.26-3.73]; P ≤ 0.01) and long-term post-cardiac surgery atrial fibrillation (7-year follow-up; HR: 2.14 [95% CI: 1.19-2.97]; P ≤ 0.01). Automated assessment of EAT volume is possible in CCTA, including in patients who are technically challenging; it forms a powerful marker of metabolically unhealthy visceral obesity, which could be used for cardiovascular risk stratification.


A Silk Fibroin Based Hydration Accelerator for Root Canal Filling Materials.
Mineral trioxide aggregate (MTA) is widely used in various dental endodontic applications such as root-end filling, furcal perforation repair, and vital pulp therapy. In spite of many attempts to improve handling properties and reduce the discoloration of MTA, the ideal root canal filling material has yet to be fully developed. The objective of this study was to investigate the setting time, mechanical properties, and biocompatibility of MTA set by a silk fibroin solution. A 5 wt% silk fibroin (SF) solution (a novel hydration accelerant) was used to set SavDen® MTA and ProRoot® white MTA (WMTA). Changes in setting time, diametral tensile strength (DTS), material crystallization, in vitro cell viability, and cell morphology were assessed by Vicat needle measurement, a universal testing machine, scanning electron microscopy (SEM), and WST-1 assay, respectively. The initial setting time of ProRoot® MTA and SavDen® MTA experienced a drastic decrease of 83.9% and 42.1% when deionized water was replaced by 5 wt% SF solution as the liquid phase. The DTS of SavDen® MTA showed a significant increase after set by the SF solution in 24 h. A human osteoblast-like cell (MG-63)-based WST-1 assay revealed that both ProRoot® MTA and SavDen® MTA hydrated using SF solution did not significantly differ (p > 0.05) in cell viability. MG-63 cells with pseudopodia attachments and nuclear protrusions represent a healthier and more adherent status on the surface of MTA when set with SF solution. The results suggest that the 5 wt% SF solution may be used as an alternative hydration accelerant for MTA in endodontic applications.


Dynamic changes of bacterial community in activated sludge with pressurized aeration in a sequencing batch reactor.
This study aimed to investigate the organic removal efficiency and microbial population dynamics in activated sludge with pressurized aeration. The activated sludge was fed with synthetic wastewater composed of simple carbon source to avoid the effect of complex components on microbial communities. The pressurized acclimation process was conducted in a bench-scale sequencing batch reactor (SBR) under 0.3 MPa gage pressure. Another SBR was running in atmospheric environment as a control reactor, with the same operation parameters except for the pressure. Bacterial diversity was investigated by Illumina sequencing technology. The results showed that the total organic carbon removal efficiency of the pressurized reactor was significantly higher, while the mixed liquor suspended solids concentrations were much lower than those of the control reactor. Moderate pressure of 0.3 MPa had little effect on Alpha-diversity of bacterial communities due to the similar running conditions, e.g., feed water, solids retention time (SRT) and the cyclic change of dissolved oxygen (DO) concentrations. Although the relative percentage of the bacterial community changed among samples, there was no major change of predominant bacterial populations between the pressurized group and the control group. Pressurized aeration would have a far-reaching impact on microbial community in activated sludge when treating wastewaters being unfavorable to the dissolution of oxygen.


Brain-derived neurotrophic factor and neurotrophin receptors modulate glutamate-induced phase shifts of the suprachiasmatic nucleus.
Light information reaches the suprachiasmatic nucleus (SCN) through a subpopulation of retinal ganglion cells. Previous work raised the possibility that brain-derived neurotrophic factor (BDNF) and its high-affinity tropomyosin-related receptor kinase may be important as modulators of this excitatory input into the SCN. In order to test this possibility, we used whole-cell patch-clamp methods to measure spontaneous excitatory currents in mouse SCN neurons. We found that the amplitude and frequency of these currents were increased by BDNF and decreased by the neurotrophin receptor inhibitor K252a. The neurotrophin also increased the magnitude of currents evoked by application of N-methyl-d-aspartate and amino-methyl proprionic acid. Next, we measured the rhythms in action potential discharge from the SCN brain slice preparation. We found that application of K252a dramatically reduced the magnitude of phase shifts of the electrical activity rhythm generated by the application of glutamate. By itself, BDNF caused phase shifts that resembled those produced by glutamate and were blocked by K252a. The results demonstrate that BDNF and neurotrophin receptors can enhance glutamatergic synaptic transmission within a subset of SCN neurons and potentiate glutamate-induced phase shifts of the circadian rhythm of neural activity in the SCN.


Rigidity enhances a magic-number effect in polymer phase separation.
Cells possess non-membrane-bound bodies, many of which are now understood as phase-separated condensates. One class of such condensates is composed of two polymer species, where each consists of repeated binding sites that interact in a one-to-one fashion with the binding sites of the other polymer. Biologically-motivated modeling revealed that phase separation is suppressed by a "magic-number effect" which occurs if the two polymers can form fully-bonded small oligomers by virtue of the number of binding sites in one polymer being an integer multiple of the number of binding sites of the other. Here we use lattice-model simulations and analytical calculations to show that this magic-number effect can be greatly enhanced if one of the polymer species has a rigid shape that allows for multiple distinct bonding conformations. Moreover, if one species is rigid, the effect is robust over a much greater range of relative concentrations of the two species.


African and Black Caribbean origin cancer survivors: a qualitative study of the narratives of causes, coping and care experiences.
Although there is evidence in the U.S.A. and U.K. to suggest that ethnic minority groups have an inferior experience of cancer care, few studies investigate ethnic disparities in satisfaction and care experiences among survivors. Patients' illness perceptions (lay explanations for illness) and coping styles (emotional and behavioural) are influenced by ethnicity-related cultural beliefs and expectations. Depressive illness or fears of recurrence of cancer may also lead to poorer recovery and function. This paper investigates whether ethnic influences explain different coping behaviours, care experiences and help-seeking behaviours. Eight participants of African or Black Caribbean origin were recruited from a London support group for a series of qualitative in-depth interviews. The interviews were recorded and transcribed, and the transcripts analysed using a framework method of qualitative data analysis. The emergent themes were tested and documented to reflect the issues of importance to patients. Lay explanations of causes of cancer were complex and diverse reflecting cultural influences and the impact of contact with health professionals. Generally, positive views about cancer care were found, especially at the secondary care level. Primary care attracted mixed views. In contrast to American studies, no acknowledgement of discrimination on the basis of ethnicity was reported. The need to be resilient and think positively were widely acknowledged as coping strategies. Some coped by avoiding contemplation of their condition or diagnosis. Religious beliefs and practices provided coping mechanisms for some, and a means to improve confidence and avoid distressing contemplation about their condition. Family, friends and charitable groups also provided emotional and practical support. Subjects were generally satisfied with their care; different coping styles included positive attitudes, minimisation of difficulties or more realistic consideration of the impact of cancer.


Biochemical evaluation of the therapeutic effectiveness of honey in oral mucosal ulcers.
The aim of this study was to describe and quantify the therapeutic value of honey in oral mucosal ulcers healing in comparison with Glyceroloxytriester (TGO). We also aimed to biochemically evaluate the healing effects of honey which had been collected from the Blacksea region flora on mucosal ulcers resulting in material loss.Thirty wistar rats (240+/-30 g) were enrolled in this study. Excisional wounds were performed in all rats for animal oral mucosal ulcer model. They were randomly allocated to three groups: group 1 was treated with Apitherapeutic agent or honey (0,1 ml, 2x1), group 2 was treated with TGO (0,1ml, 2x1) locally, Group 3 served as the control group.Following the surgical procedure on day 7, biopsy specimens were taken from right buccal mucosa and on day 14 biopsy specimens were taken from left bucal mucosa in all rats. Afterwards, hydroxy pyroline levels were measured. Data were analyzed statistically.There was no statistically significant difference between Group 1 and 2, and also between Group 2 and 3, but there was statistically significant difference between Group 1 and 3 on day 7. There was no statistically significant difference between Group 1, 2 and 3 on day 14.


The growing role of bariatric surgery in the management of type 2 diabetes: evidences and open questions.
The use of bariatric surgery in the clinical management of type 2 diabetes has been recently endorsed in the clinical practice recommendations released by the most influential diabetologic associations. However, authoritative critic voices about the application of metabolic surgery in type 2 diabetes continue to appear in diabetologic literature. In this review, we will try therefore to understand what the reasons for this apparent dichotomy. In this paper, we revised what we believe are now clear evidences about the role of bariatric surgery in the treatment of type 2 diabetes in patients with morbid obesity: the efficacy of bariatric surgery in metabolic control, the existence of plausible weight-independent metabolic mechanisms at least in some bariatric procedure, and the importance of the early referral to surgery in patients with firm indications. However, we stressed also the lack of clear high-quality long-term data about the effects of bariatric surgery in the prevention of both macro- and micro-vascular hard endpoints in patients with type 2 diabetes. The accrual of these results will be critical to completely clarify the risk/benefit ratio of bariatric surgery in diabetes, as compared to current pharmacologic therapies. This may be particularly important in patients in which data on long-term efficacy are still not completed, such as in patients with lower BMI levels.


Cardiovascular disease and hypertension risk in living kidney donors: an analysis of health administrative data in Ontario, Canada.
Knowledge of any harm associated with living kidney donation guides informed consent and living donor follow-up. Risk estimates in the literature are variable, and most studies did not use a healthy control group to assess outcomes attributable to donation. We observed a retrospective cohort using health administrative data for donations which occurred in Ontario, Canada between the years 1993 and 2005. There were a total of 1278 living donors and 6359 healthy adults who acted as a control group. Individuals were followed for a mean of 6.2 years (range, 1-13 years) after donation. The primary outcome was a composite of time to death or first cardiovascular event (myocardial infarction, stroke, angioplasty, and bypass surgery). The secondary outcome was time to a diagnosis of hypertension. There was no significant difference in death or cardiovascular events between donors and controls (1.3% vs. 1.7%; hazard ratio 0.7, 95% confidence interval 0.4-1.2). Donors were more frequently diagnosed with hypertension than controls (16.3% vs. 11.9%, hazard ratio 1.4, 95% confidence interval 1.2-1.7) but were also seen more often by their primary care physicians (median [interquartile range] 3.6 [1.9-6.1] vs. 2.6 [1.4-4.3] visits per person year, P<0.001). Based on administrative data, the risk of cardiovascular disease was unchanged in the first decade after kidney donation. The observed increase in diagnosed hypertension may be due to nephrectomy or more blood pressure measurements received by donors in follow-up and requires prospective study.


EphA4 Receptor Forward Signaling Inhibits Glucagon Secretion From α-Cells.
The loss of inhibition of glucagon secretion exacerbates hyperglycemia in type 1 and 2 diabetes. However, the molecular mechanisms that regulate glucagon secretion in unaffected and diabetic states remain relatively unexplained. We present evidence supporting a new model of juxtacrine-mediated regulation of glucagon secretion where neighboring islet cells negatively regulate glucagon secretion through tonic stimulation of α-cell EphA receptors. Primarily through EphA4 receptors, this stimulation correlates with maintenance of a dense F-actin network. In islets, additional stimulation and inhibition of endogenous EphA forward signaling result in inhibition and enhancement, respectively, of glucagon secretion, accompanied by an increase and decrease, respectively, in α-cell F-actin density. Sorted α-cells lack endogenous stimulation of EphA forward signaling from neighboring cells, resulting in enhanced basal glucagon secretion as compared with islets and the elimination of glucose inhibition of glucagon secretion. Restoration of EphA forward signaling in sorted α-cells recapitulates both normal basal glucagon secretion and glucose inhibition of glucagon secretion. Additionally, α-cell-specific EphA4(-/-) mice exhibit abnormal glucagon dynamics, and EphA4(-/-) α-cells contain less dense F-actin networks than EphA4(+/+) α-cells. This juxtacrine-mediated model provides insight into the functional and dysfunctional regulation of glucagon secretion and opens up new therapeutic strategies for the clinical management of diabetes.


Structural and kinetic analysis of protein-aggregate strains in vivo using binary epitope mapping.
Despite considerable progress in uncovering the molecular details of protein aggregation in vitro, the cause and mechanism of protein-aggregation disease remain poorly understood. One reason is that the amount of pathological aggregates in neural tissue is exceedingly low, precluding examination by conventional approaches. We present here a method for determination of the structure and quantity of aggregates in small tissue samples, circumventing the above problem. The method is based on binary epitope mapping using anti-peptide antibodies. We assessed the usefulness and versatility of the method in mice modeling the neurodegenerative disease amyotrophic lateral sclerosis, which accumulate intracellular aggregates of superoxide dismutase-1. Two strains of aggregates were identified with different structural architectures, molecular properties, and growth kinetics. Both were different from superoxide dismutase-1 aggregates generated in vitro under a variety of conditions. The strains, which seem kinetically under fragmentation control, are associated with different disease progressions, complying with and adding detail to the growing evidence that seeding, infectivity, and strain dependence are unifying principles of neurodegenerative disease.


Foil backing used in intraoral radiographic dental film: a source of environmental lead.
The lead content of the foil backing of 4 types of intraoral film commonly used by dentists was 69% to 85%. An environmental issue exists because these foils are typically thrown out with regular refuse, even though recycling programs exist. For a new adult patient, a full-mouth radiographic series would generate 11.2 g of waste lead; for a 6-month checkup, waste lead would only be produced if radiographs were required. In an experiment that simulated the acidic conditions that might be expected in a landfill site, 3.5-4.4 mg of lead was released during 17-hour incubation in dilute acetic acid. When distilled double-deionized water replaced the acid, 1.0-2.2 mg of lead was released by the same types of foils. Human health concerns also exist when dental assistants handle lead foil while developing radiographs and fail to change their gloves or wash their hands before handling instruments and dental paraphernalia used in the mouth. Although the amount of lead introduced into the oral cavity would be relatively small, the elimination of sources of lead exposure, especially for children, is important.


An electrostatic elliptical mirror for neutral polar molecules.
Focusing optics for neutral molecules finds application in shaping and steering molecular beams. Here we present an electrostatic elliptical mirror for polar molecules consisting of an array of microstructured gold electrodes deposited on a glass substrate. Alternating positive and negative voltages applied to the electrodes create a repulsive potential for molecules in low-field-seeking states. The equipotential lines are parallel to the substrate surface, which is bent in an elliptical shape. The mirror is characterized by focusing a beam of metastable CO molecules and the results are compared to the outcome of trajectory simulations.


Supporting clinical rules engine in the adjustment of medication (SCREAM): protocol of a multicentre, prospective, randomised study.
In the nursing home population, it is estimated that 1 in every 3 patients is polymedicated and given their considerable frailty, these patients are especially prone to adverse drug reactions. Clinical pharmacist-led medication reviews are considered successful interventions to improve medication safety in the inpatient setting. Due to the limited available evidence concerning the benefits of medication reviews performed in the nursing home setting, we propose a study aiming to demonstrate a positive effect that a clinical decision support system, as a health care intervention, may have on the target population. The primary objective of this study is to reduce the number of patients with at least one event when using the clinical decision support system compared to the regular care. These events consist of hospital referrals, delirium, falls, and/or deaths. This study is a multicentre, prospective, randomised study with a cluster group design. The randomisation will be per main nursing home physician and stratified per ward (somatic and psychogeriatric). In the intervention group the clinical decision support system will be used to screen medication list, laboratory values and medical history in order to obtain potential clinical relevant remarks. The remarks will be sent to the main physician and feedback will be provided whether the advice was followed or not. In the control group regular care will be applied. We strongly believe that by using a clinical decision support system, medication reviews are performed in a standardised way which leads to comparable results between patients. In addition, using a clinical decision support system eliminates the time factor to perform medication reviews as the major problems related to medication, laboratory values, indications and/or established patient characteristics will be directly available. In this way, and in order to make the medication review process complete, consultation within healthcare professionals and/or the patient itself will be time effective and the medication surveillance could be performed around the clock. The Netherlands National Trial Register NTR5165 . Registered 2nd April 2015.


Loss of the ClC-7 chloride channel leads to osteopetrosis in mice and man.
Chloride channels play important roles in the plasma membrane and in intracellular organelles. Mice deficient for the ubiquitously expressed ClC-7 Cl(-) channel show severe osteopetrosis and retinal degeneration. Although osteoclasts are present in normal numbers, they fail to resorb bone because they cannot acidify the extracellular resorption lacuna. ClC-7 resides in late endosomal and lysosomal compartments. In osteoclasts, it is highly expressed in the ruffled membrane, formed by the fusion of H(+)-ATPase-containing vesicles, that secretes protons into the lacuna. We also identified CLCN7 mutations in a patient with human infantile malignant osteopetrosis. We conclude that ClC-7 provides the chloride conductance required for an efficient proton pumping by the H(+)-ATPase of the osteoclast ruffled membrane.


Economic burden of maternal morbidity - A systematic review of cost-of-illness studies.
To estimate the economic burden of common health problems associated with pregnancy and childbirth, such as incontinence, mental health problems, or gestational diabetes, excluding acute complications of labour or birth, or severe acute adverse maternal outcomes. Searches for relevant studies were carried out to November 2019 in Medline, Embase, CINAHL, PsycINFO and EconLit databases. After initial screening, all results were reviewed for inclusion by two authors. An adapted version of a previously developed checklist for cost-of-illness studies was used for quality appraisal. All costs were converted to 2018 Euro using national consumer price indices and purchasing power parity conversion factors. Thirty-eight relevant studies were identified, some of which reported incremental costs for more than one health problem (16 gestational diabetes, 13 overweight/obesity, 8 mental health, 4 hypertensive disorders, 2 nausea and vomiting, 2 epilepsy, 1 intimate partner violence). A high level of heterogeneity was observed in both the methods used, and the incremental cost estimates obtained for each morbidity. Average incremental costs tended to be higher in studies that modelled a hypothetical cohort of women using data from a range of sources (compared to analyses of primary data), and in studies set in the United States. No studies that examined the economic burden of some common pregnancy-related morbidities, such as incontinence, pelvic girdle pain, or sexual health problems, were identified. Our findings indicate that maternal morbidity is associated with significant costs to health systems and society, but large gaps remain in the evidence base for the economic burden of some common health problems associated with pregnancy and childbirth. More research is needed to examine the economic burden of a range of common maternal health problems, and future research should adopt consistent methodological approaches to ensure comparability of results.


Identification and characterization of putative tumor suppressor NGB, a GTP-binding protein that interacts with the neurofibromatosis 2 protein.
Mutations of the neurofibromatosis 2 (NF2) tumor suppressor gene have frequently been detected not only in schwannomas and other central nervous system tumors of NF2 patients but also in their sporadic counterparts and malignant tumors unrelated to the NF2 syndrome such as malignant mesothelioma, indicating a broader role for the NF2 gene in human tumorigenesis. However, the mechanisms by which the NF2 product, merlin or schwannomin, is regulated and controls cell proliferation remain elusive. Here, we identify a novel GTP-binding protein, dubbed NGB (referring to NF2-associated GTP binding protein), which binds to merlin. NGB is highly conserved between Saccharomyces cerevisiae, Caenorhabditis elegans, and human cells, and its GTP-binding region is very similar to those found in R-ras and Rap2. However, ectopic expression of NGB inhibits cell growth, cell aggregation, and tumorigenicity in tumorigenic schwanomma cells. Down-regulation and infrequent mutation of NGB were detected in human glioma cell lines and primary tumors. The interaction of NGB with merlin impairs the turnover of merlin, yet merlin does not affect the GTPase nor GTP-binding activity of NGB. Finally, the tumor suppressor functions of NGB require merlin and are linked to its ability to suppress cyclin D1 expression. Collectively, these findings indicate that NGB is a tumor suppressor that regulates and requires merlin to suppress cell proliferation.


Comparative evaluation of gene set analysis approaches for RNA-Seq data.
Over the last few years transcriptome sequencing (RNA-Seq) has almost completely taken over microarrays for high-throughput studies of gene expression. Currently, the most popular use of RNA-Seq is to identify genes which are differentially expressed between two or more conditions. Despite the importance of Gene Set Analysis (GSA) in the interpretation of the results from RNA-Seq experiments, the limitations of GSA methods developed for microarrays in the context of RNA-Seq data are not well understood. We provide a thorough evaluation of popular multivariate and gene-level self-contained GSA approaches on simulated and real RNA-Seq data. The multivariate approach employs multivariate non-parametric tests combined with popular normalizations for RNA-Seq data. The gene-level approach utilizes univariate tests designed for the analysis of RNA-Seq data to find gene-specific P-values and combines them into a pathway P-value using classical statistical techniques. Our results demonstrate that the Type I error rate and the power of multivariate tests depend only on the test statistics and are insensitive to the different normalizations. In general standard multivariate GSA tests detect pathways that do not have any bias in terms of pathways size, percentage of differentially expressed genes, or average gene length in a pathway. In contrast the Type I error rate and the power of gene-level GSA tests are heavily affected by the methods for combining P-values, and all aforementioned biases are present in detected pathways. Our result emphasizes the importance of using self-contained non-parametric multivariate tests for detecting differentially expressed pathways for RNA-Seq data and warns against applying gene-level GSA tests, especially because of their high level of Type I error rates for both, simulated and real data.


U.S. Postlicensure safety surveillance for adolescent and adult tetanus, diphtheria and acellular pertussis vaccines: 2005-2007.
Pre-licensure clinical trials for two U.S. licensed tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccines did not reveal any major safety concerns. However, routine use in large adolescent and adult populations could reveal rare and potentially serious adverse events (AEs). To characterize reported AEs following Tdap vaccination and identify potential safety concerns warranting further evaluation, we analyzed data from the Vaccine Adverse Event Reporting System (VAERS) and assessed the frequency and proportions of AEs and reporting rates (reports per 100,000 vaccine doses distributed). A total of 2090 reports (7% were serious; 55% listed Tdap alone) involving Tdap vaccines were submitted to VAERS May 2005-June 2007. The crude reporting rate was 10.2 per 100,000 vaccine doses distributed. The median age of vaccinees was 22 years, and the female to male ratio was about 2 to 1. The majority of reports described common local and systemic signs and symptoms, such as injection site reactions, fever, and headache. Rarely reported AEs included myopericarditis, demyelinating diseases of the central nervous system, Guillain-Barré Syndrome, syncope, encephalopathy/encephalitis, seizure, Bell's palsy, anaphylaxis, and thrombocytopenia. Because adolescents and adults were not routinely vaccinated against pertussis in the past, this surveillance summary provides important - and reassuring - information about the use of Tdap in these age groups. Although subject to the limitations of passive surveillance, the findings of this VAERS review support the pre-licensure clinical trial data with regard to the safety of the U.S. licensed Tdap vaccines. Continued monitoring of clinically significant AEs that are temporally associated with Tdap vaccination and further assessment of such events using controlled observational studies may provide additional information about the safety of these vaccines.


Exploring and exploiting epigenetic variation in crops.
This review addresses the mechanisms by which epigenetic variation modulates plant gene regulation and phenotype. In particular we explore the scope for harnessing such processes within the context of crop genetic improvement. We focus on the role of DNA methylation as an epigenetic mark that contributes to epiallelic diversity and modulation of gene regulation. We outline the prevalence and distribution of epigenetic marks in relation to eukaryote developmental processes, and in particular identify where this may be relevant to crop traits both in terms of specific developmental stages and in relation to physiological responses to environmental change. Recent whole genome surveys have identified specific characteristics of the distribution of DNA methylation within plant genomes. Together with greater understanding of the mode of action of different maintenance and de novo methyltransferases, this provides an opportunity to modulate DNA methylation status at specific loci as an intervention strategy in crop genetic improvement. We discuss alternative approaches that may be suitable for harnessing such induced epiallelic variation. Most of the discussion is associated with Brassica crops, which demonstrate considerable morphological plasticity, segmental chromosomal duplication, and polyploidy.


Folding of a helix at room temperature is critically aided by electrostatic polarization of intraprotein hydrogen bonds.
We report direct folding of a 17-residue helix protein (pdb:2I9M) by standard molecular dynamics simulation (single trajectory) at room temperature with implicit solvent. Starting from a fully extended structure, 2I9M successfully folds into the native conformation within 16 ns using adaptive hydrogen bond-specific charges to take into account the electrostatic polarization effect. Cluster analysis shows that conformations in the native state cluster have the highest population (78.4%) among all sampled conformations. Folding snapshots and the secondary structure analysis demonstrate that the folding of 2I9M begins at terminals and progresses toward the center. A plot of the free energy landscape indicates that there is no significant free energy barrier during folding, which explains the observed fast folding speed. For comparison, exactly the same molecular dynamics simulation but carried out under existing AMBER charges failed to fold 2I9M into native-like structures. The current study demonstrates that electrostatic polarization of intraprotein hydrogen bonding, which stabilizes the helix, is critical to the successful folding of 2I9m.


Structure of fungal fatty acid synthase and implications for iterative substrate shuttling.
We report crystal structures of the 2.6-megadalton alpha6beta6 heterododecameric fatty acid synthase from Thermomyces lanuginosus at 3.1 angstrom resolution. The alpha and beta polypeptide chains form the six catalytic domains required for fatty acid synthesis and numerous expansion segments responsible for extensive intersubunit connections. Detailed views of all active sites provide insights into substrate specificities and catalytic mechanisms and reveal their unique characteristics, which are due to the integration into the multienzyme. The mode of acyl carrier protein attachment in the reaction chamber, together with the spatial distribution of active sites, suggests that iterative substrate shuttling is achieved by a relatively restricted circular motion of the carrier domain in the multifunctional enzyme.


Structure of human CD1b with bound ligands at 2.3 A, a maze for alkyl chains.
The human genome encodes five nonpolymorphic major histocompatibility complex class I-like glycoproteins, CD1a to CD1e, that present lipid antigens for specific recognition by T lymphocytes. Using single alkyl chain detergents, we developed a protocol to generate recombinant human CD1b-lipid complexes. We present here the crystal structures of CD1b in complex with either phosphatidylinositol or ganglioside GM2 at 2.3 A and 2.8 A resolutions, respectively. The antigen-binding groove houses four interlinked hydrophobic channels that are occupied by the alkyl chains of the glycolipid plus two detergent molecules. A distinct exit beneath the alpha 2 helix further contributes to the plasticity of the binding groove. These structures reveal the mechanism by which two alkyl chain lipids bind to CD1b, and how CD1b can adapt to ligands of different alkyl chain length. They also suggest how very long alkyl chains, such as those of mycolic acid, could be fully contained within the binding groove. These results extend the spectrum of potential CD1b ligands by revealing that, in addition to two alkyl chain lipids, mono-alkyl and triple-alkyl chain lipids can be accommodated in the binding groove.


Neural network analysis of clinicopathological and molecular markers in bladder cancer.
To evaluate retrospectively the ability of an artificial neural network (ANN) to predict bladder cancer recurrence within 6 months of diagnosis and stage progression in patients with Ta/T1 bladder cancer, and 12-month cancer-specific survival in patients with T2-T4 bladder cancer. Data were analyzed using a NeuralWorks Professional II/Plus software package. The input neural data consisted of clinicopathological and molecular characteristics. Distinct patient groups were used for the prediction of stage progression and tumor recurrence in Ta/T1 bladder cancers, and 12-month cancer-specific survival for patients with T2-T4 tumors. ANN predictions were compared with those of four consultant urologists. The accuracy of the neural network in predicting stage progression and recurrence within 6 months for Ta/T1 tumors and 12-month cancer-specific survival for T2-T4 cancers was 80%, 75% and 82% respectively; with corresponding figures for clinicians being 74%, 79% and 65%. On restricting the validation subset to patients with T1G3 tumors in relation to stage progression, the sensitivity of the ANN analysis increased to 100% with a specificity of 78% and an overall accuracy of 82%. The performance of the ANN in predicting stage progression in T1G3 tumors was significantly higher than that of clinicians (p = 0.25 for the ANN and p = 0.008 for clinicians, McNemar test). Data analysis using an ANN has been shown to be a useful adjunct in predicting outcomes in patients with bladder cancer and out-performs clinicians' predictions of stage progression in the high risk group of patients with T1G3 disease.


Platelet-Rich Plasma Does Not Inhibit Inflammation or Promote Regeneration in Human Osteoarthritic Chondrocytes In Vitro Despite Increased Proliferation.
The aims of the study were to assess the anti-inflammatory properties of platelet-rich plasma (PRP) and investigate its regenerative potential in osteoarthritic (OA) human chondrocytes. We hypothesized that PRP can modulate the inflammatory response and stimulate cartilage regeneration. Primary human chondrocytes from OA knees were treated with manually prepared PRP, after which cell migration and proliferation were assessed. Next, tumor necrosis factor-α-stimulated chondrocytes were treated with a range of concentrations of PRP. Expression of genes involved in inflammation and chondrogenesis was determined by real-time polymerase chain reaction. In addition, chondrocytes were cultured in PRP gels and fibrin gels consisting of increasing concentrations of PRP. The production of cartilage extracellular matrix (ECM) was assessed. Deposition and release of glycosaminoglycans (GAG) and collagen was quantitatively determined and visualized by (immuno)histochemistry. Proliferation was assessed by quantitative measurement of DNA. Both migration and the inflammatory response were altered by PRP, while proliferation was stimulated. Expression of chondrogenic markers COL2A1 and ACAN was downregulated by PRP, independent of PRP concentration. Chondrocytes cultured in PRP gel for 28 days proliferated significantly more when compared with chondrocytes cultured in fibrin gels. This effect was dose dependent. Significantly less GAGs and collagen were produced by chondrocytes cultured in PRP gels when compared with fibrin gels. This was qualitatively confirmed by histology. PRP stimulated chondrocyte proliferation, but not migration. Also, production of cartilage ECM was strongly downregulated by PRP. Furthermore, PRP did not act anti-inflammatory on chondrocytes in an in vitro inflammation model.


A report of two cases of unilateral vestibulopathie after systemic ototoxic treatment.
To present the cases of two patients that developed unilateral vestibular hypofunction after systemic treatment with ototoxic agents, although they manifested symptoms more typical of bilateral vestibular hypofunction. The patients were seen after having recovered from their initial illnesses, and both of them denied suffering any spells of vertigo, loss of hearing during the treatment or tinnitus. In both patients, oscillopsia and vestibular ataxia were of varying intensity. Bedside vestibular examination, caloric and rotatory chair testing, and vestibular evoked myogenic potentials were congruent with a complete unilateral loss of vestibular function. Audiometry was normal in one case whereas in the other, there was a moderate bilateral sensorineural loss of hearing that was present before treatment and that did not change during the course of the treatment. The existence of unilateral vestibular loss was an unsuspected finding but after careful bedside examination, it was confirmed through extensive vestibular testing. However, this infrequent finding responded very well to vestibular rehabilitation. Different mechanisms are proposed to explain this phenomenon, although there is still no clear evidence of which may account for the responses observed.


TFII-I gene family during tooth development: candidate genes for tooth anomalies in Williams syndrome.
Williams syndrome is a rare congenital disorder involving the cardiovascular system, mental retardation, distinctive facial features, and tooth anomalies. It is caused by the heterozygous deletion of approximately 1.6 Mb encompassing 28 genes on human chromosome 7q11.23. It has been suggested that the genes responsible for craniofacial anomalies are located in the telomeric end region, which harbors three members of the TFII-I gene family (Tassabehji et al. [2005] Science 310:1184). To recognize potential candidate genes for the tooth anomalies in Williams syndrome, we carried out comparative in situ hybridization analysis of members of TFII-I gene family during murine odontogenesis. Gtf2i showed widespread expression in the developing head but was higher in the developing teeth than surrounding tissues throughout tooth development. At the bud stage, Gtf2ird1 and Gtf2ird2 were expressed in the epithelial buds. At the early bell stage, expression of Gtf2ird1 and Gtf2ird2 was observed in preameloblasts and preodontoblasts.


Serum cardiac enzymes in stroke.
Serum cardiac enzyme levels (CK, LDH, SGOT) were estimated and the ECG recorded for 4 days following admission of 288 patients (Group I) to a stroke intensive care unit. Sixty-four of these patients, subsequently found not to have strokes, served as controls. Mean serum levels of all 3 cardiac enzymes were elevated in 8% of the 224 patients with stroke. The mean serum enzyme levels in patients with transient ischemic attacks (TIA) did not differ from controls. In a second group of 230 patients with stroke (Group II) serum CK levels were measured and the isoenzyems were fractionated to determine the tissue source of the enzymes. One hundred and one patients had raised total CK values and 25 of these (11%) had raised CK-MB (heart) iso-enzyme, the remainder having CK-MM (skeletal muscle) fraction. No serum CK-BB (brain) iso-enzyme was detected in any patient. Patients with positive serum levels of CK-MB has more evidence of acute myocardial ischemia on ECG (p less than 0.05), and more cardiac arrhythmias (p less than 0.001) than those with normal CK levels. Scattered areas of myocytolysis were found in the myocardium at autopsy in one patient. The acute rise in serum cardiac enzymes which we have recorded in the initial stages of stroke suggest that acute myocardial involvement is a commoner complication than is generally recognized. Also, since the CK-MB rises were modest and progressive, it is more likely that this acute myocardial dysfunction is a consequence, rather than a cause, of the acute cerebrovascular lesion.


Equity implications of coverage and use of insecticide treated nets distributed for free or with co-payment in two districts in Tanzania: A cross-sectional comparative household survey.
In Tanzania, the distribution and coverage of insecticide-treated nets (ITNs) is inequitable. Arguments about the most effective and equitable approach to distributing ITNs centre around whether to provide ITNs free of charge or continue with existing social marketing strategies. The Government has decided to provide free ITNs to all children under five in the country. It is still uncertain whether this strategy will achieve equitable coverage and use. This study examined the equity implications of ownership and use of ITNs in households from different socioeconomic quintiles in a district with free ITNs and a district without free ITN distribution. A cross-sectional comparative household survey was conducted in two districts: Mpanda in Rukwa Region (with free ITN roll out) and Kisarawe in Coast region (without free ITNs). Heads of 314 households were interviewed in Mpanda and Kisarawe. The concentration index was estimated and regression analysis was performed to compare socioeconomic inequalities in ownership and use of ITNs. Ownership of ITNs increased from 29% in the 2007/08 national survey to 90% after the roll out of free ITNs in Mpanda, and use increased from 13% to 77%. Inequality was considerably lower in Mpanda, with nearly perfect equality in use (concentration index 0.009) and ownership (concentration index 0.010). In Kisarawe, ownership of ITNs increased from 48% in the 2007/08 national survey to 53%, with a marked inequality concentration index 0.132. ITN use in Kisarawe district was 42% with a pro rich concentration index of 0.027. The results shed some light on the possibilities of reducing inequality in ownership and use of ITNs and attaining Roll Back Malaria and Millennium Development Goals through the provision of free ITNs to all. This has the potential to decrease the burden of disease and reduce disparity in disease outcome.


Health care expenditures associated with depression in adults with cancer.
The rates of depression in adults with cancer have been reported as high as 38%-58%. How depression affects overall health care expenditures in individuals with cancer is an under-researched area. To estimate excess average total health care expenditures associated with depression in adults with cancer by comparing those with and without depression after controlling for demographic, socioeconomic, access to care, and other health status variables. Cross-sectional data on 4,766 adult survivors of cancer from 2006-2009 of the nationally representative household survey, Medical Expenditure Panel Survey (MEPS), were used. The patients were older than 21 years. Cancer and depression were identified from the patients' medical conditions files. Dependent variables consisted of total, inpatient, outpatient, emergency department, prescription drugs, and other expenditures. Ordinary least square (OLS) on logged dollars and generalized linear models with log-link function were performed. All analyses (SAS 9.3 and STATA12) accounted for the complex survey design of the MEPS. Overall, 14% of individuals with cancer reported having depression. In those with cancer and depression, the average annual health care expenditures were $18,401 compared with $12,091 in those without depression. After adjusting for demographic, socioeconomic, access to care, and other health status variables, those with depression had about 31.7% greater total expenditures compared with those without depression. Total, outpatient, and prescription expenditures were higher in individuals with depression than in those without depression. Individuals with cancer and depression were significantly more likely to use emergency departments (adjusted odds ratio, 1.46) compared with their counterparts without depression. Cancer patients who died during the reporting year were excluded. The financial burden of depression may have been underestimated because the costs of end-of-life care are high. The burden for each cancer type was not analyzed because of the small sample size. In adults with cancer, those with depression had higher health care utilization and expenditures compared with those without depression. One author was partially supported by the National Institute of General Medical Sciences, U54GM104942.


Interleukin-13 as an important cytokine: A review on its roles in some human diseases.
Interleukin-13 (IL-13) as a pleiotropic cytokine acts through the IL-13Ra1/IL-4Ra complex to induce activation responses which contribute to the inflammatory diseases. Genetic polymorphisms in IL-13 and its receptor components have been proved to be associated with higher disease prevalence rates. Animal models such as in IL-13 deficient mice and transgenic animals also have been confirmed the critical role of this cytokine in the immune responses, mostly by IL-13 neutralization and IL-13/IL-4 dual neutralization strategies. This review highlights IL-13 structure as well as its pivotal roles in the normal physiologic and pathologic states. It is followed by a section on the recent findings on IL-13 receptors and signalling mechanisms to briefly summarize its functions in the immune systems. IL-13 roles in the human diseases such as asthma, systematic sclerosis, and some inflammatory diseases are described concisely. Finally some of the ongoing therapeutic applications are presented to comprehensively review IL-13 mediator roles.


Patient-Derived Xenograft Establishment from Human Malignant Pleural Mesothelioma.
Purpose: Malignant pleural mesothelioma (MPM) is a rare but aggressive disease with few therapeutic options. The tumor-stromal interface is important in MPM, but this is lost in cell lines, the main model used for preclinical studies. We sought to characterize MPM patient-derived xenografts (PDX) to determine their suitability as preclinical models and whether tumors that engraft reflect a more aggressive biological phenotype.Experimental Design: Fresh tumors were harvested from extrapleural pneumonectomy, decortication, or biopsy samples of 50 MPM patients and implanted subcutaneously into immunodeficient mice and serially passaged for up to five generations. We correlated selected mesothelioma biomarkers between PDX and patient tumors, and PDX establishment with the clinical pathologic features of the patients, including their survival. DNA of nine PDXs was profiled using the OncoScan FFPE Express platform. Ten PDXs were treated with cisplatin and pemetrexed.Results: A PDX was formed in 20 of 50 (40%) tumors implanted. Histologically, PDX models closely resembled the parent tumor. PDX models formed despite preoperative chemotherapy and radiotherapy. In multivariable analysis, patients whose tumors formed a PDX had significantly poorer survival when the model was adjusted for preoperative treatment (HR, 2.46; 95% confidence interval, 1.1-5.52; P = 0.028). Among 10 models treated with cisplatin, seven demonstrated growth inhibition. Genomic abnormalities seen in nine PDX models were similar to that previously reported.Conclusions: Patients whose tumors form PDX models have poorer clinical outcomes. MPM PDX tumors closely resemble the genotype and phenotype of parent tumors, making them valuable models for preclinical studies. Clin Cancer Res; 23(4); 1060-7. ©2016 AACR.


The sociometry and sociogenesis of reproduction in the Florida harvester ant, Pogonomyrmex badius.
The colony is the functional unit of natural selection for most social insects including the Florida harvester ant, Pogonomyrmex badius . To address reproduction in the species variables were evaluated relevant to the colony-level (sociometry), and social growth (sociogenesis). Colonies become reproductively mature when the worker population reaches approximately 700 individuals. The production of males and gynes (reproductive females) occurs only in spring, and is highly synchronized from its onset, which in turn allows synchronization of mating in early summer. Worker production follows sexual production, and continues until colonies go dormant in winter. Once mature, colony investment into reproduction is a constant proportion of colony size (isometric), regardless of the sex ratio produced. As individual male body size increases, they become leaner, whereas the amount of fat stored by gynes is highly variable. Larger colonies produce larger males, but gyne size is a constant across the range of colony sizes. As colony size increases, investment into males increases faster than investment into gynes. Therefore, there is a trend of increasing male bias in the sex ratio with increasing colony size (although a single outlier complicates this conclusion). We interpret our results in the light of sexual and natural selection as documented in related species. We also report the first documentation of male production by workers in the genus Pogonomyrmex .


Systemic and local anti-C5 therapy reduces the disease severity in experimental autoimmune uveoretinitis.
Activation of complement occurs during autoimmune retinal and intraocular inflammatory disease as well as neuroretinal degenerative disorders. The cleavage of C5 into fragments C5a and C5b is a critical event during the complement cascade. C5a is a potent proinflammatory anaphylatoxin capable of inducing cell migration, adhesion and cytokine release, while membrane attack complex C5b-9 causes cell lysis. Therapeutic approaches to prevent complement-induced inflammation include the use of blocking monoclonal antibodies (mAb) to prevent C5 cleavage. In these current experiments, the rat anti-mouse C5 mAb (BB5.1) was utilized to investigate the effects of inhibition of C5 cleavage on disease progression and severity in experimental autoimmune uveoretinitis (EAU), a model of organ-specific autoimmunity in the eye characterized by structural retinal damage mediated by infiltrating macrophages. Systemic treatment with BB5.1 results in significantly reduced disease scores compared with control groups, while local administration results in an earlier resolution of disease. In vitro, contemporaneous C5a and interferon-gamma signalling enhanced nitric oxide production, accompanied by down-regulation of the inhibitory myeloid CD200 receptor, contributing to cell activation. These experiments demonstrate that C5 cleavage contributes to the full expression of EAU, and that selective C5 blockade via systemic and local routes of administration can suppress disease. This presents great therapeutic potential to protect against tissue damage during autoimmune responses in the retina or inflammation-induced degenerative disease.


Overexpression of a mutant form of EhRabA, a unique Rab GTPase of Entamoeba histolytica, alters endoplasmic reticulum morphology and localization of the Gal/GalNAc adherence lectin.
Entamoeba histolytica is a protozoan parasite that causes amoebic dysentery and liver abscess. Vesicle trafficking events, such as phagocytosis and delivery of plasma membrane proteins, have been implicated in pathogenicity. Rab GTPases are proteins whose primary function is to regulate vesicle trafficking; therefore, understanding the function of Rabs in this organism may provide insight into virulence. E. histolytica possesses a number of unique Rabs that exhibit limited homology to host Rabs. In this study we examined the function of one such Rab, EhRabA, by characterizing a mutant overexpressing a constitutively GTP-bound version of the protein. Overexpression of mutant EhRabA resulted in decreased adhesion to and phagocytosis of human red blood cells and in the appearance of large tubular organelles that could be stained with endoplasmic reticulum (ER)-specific but not Golgi complex-specific antibodies. Consistent with the adhesion defect, two subunits of a cell surface adhesin, the galactose/N-acetylgalactosamine lectin, were mislocalized to the novel organelle. A cysteine protease, EhCP2, was also localized to the ER-like compartment in the mutant; however, the localization of two additional cell surface proteins, Igl and SREHP, remained unchanged in the mutant. The phenotype of the mutant could be recapitulated by treatment with brefeldin A, a cellular toxin that disrupts ER-to-Golgi apparatus vesicle traffic. This suggests that EhRabA influences vesicle trafficking pathways that are also sensitive to brefeldin A. Together, the data indicate that EhRabA directly or indirectly influences the morphology of secretory organelles and regulates trafficking of a subset of secretory proteins in E. histolytica.


Amphetamine and pseudoephedrine cross-tolerance measured by c-Fos protein expression in brains of chronically treated rats.
Pseudoephedrine is a drug commonly prescribed as a nasal decongestant and bronchodilator and is also freely available in cold remedies and medications. The structural and pharmacological similarity of pseudoephedrine to amphetamine has led to evaluation of its psychomotor stimulant properties within the central nervous system. Previous investigations have shown that the acute responses to pseudoephedrine were similar to those of amphetamine and other psychostimulants. This study examined the effect of chronic administration of pseudoephedrine in rat nucleus accumbens and striatum and identified three further similarities to amphetamine. (i) Chronic exposure to pseudoephedrine reduced the c-Fos response to acute pseudoephedrine treatment suggesting that pseudoephedrine induced tolerance in the animals. (ii) In animals chronically treated with amphetamine or pseudoephedrine the acute c-Fos response to pseudoephedrine and amphetamine was reduced respectively as compared to naïve animals indicating cross-tolerance for the two drugs. (iii)The known involvement of the dopamine system in the response to amphetamine and pseudoephedrine was further confirmed in this study by demonstrating that pseudoephedrine similarly to amphetamine, but with lower potency, inhibited [3H]dopamine uptake in synaptosomal preparations. This work has demonstrated further similarities of the effect of pseudoephedrine to those of amphetamine in brain areas known to be associated with drug addiction. The most significant result presented here is the cross tolerance effect of amphetamine and pseudoephedrine. This suggests that both drugs induce similar mechanisms of action in the brain. Further studies are required to establish whether despite its considerable lower potency, pseudoephedrine could pose health and addiction risks in humans similar to that of known psychostimulants.


The effect of procyanidin on expression of STAT1 in type 2 diabetes mellitus SD rats with focal cerebral ischemia.
Diabetes with cerebral infarction is a common disease that severely impacts health. This study investigated the effect of procyanidin (PC) on the expression of signal transducers and activators of transcription (STAT1) in type 2 diabetes mellitus SD rats with focal cerebral ischemia. We then explored the protective mechanisms of PC in type 2 diabetes mellitus SD rats with focal cerebral ischemia, to provide theory evidence for its clinical application. We set up a type 2 diabetes mellitus-MCAO model, evaluated neurological function, and used immunohistochemistry methods to measure the activity of STAT1. The brain expression of STAT1 in rats of the sham-operation group was low, but more STAT1 positive cells were found in normal rats with ischemia and in rats with both type 2 diabetes and ischemia when groups were compared with the sham-operation group (p<0.01). Compared with rats that had type 2 diabetes and ischemia, the numbers of STAT1 positive cells after low, medium and high-doses of PC were all decreased (p<0.01), whereby the mid and high-dose groups showed a more substantial decrease (p<0.01) and with no variance between the two groups (p>0.05). These results indicate that PC has a neuroprotective effect on type 2 diabetes mellitus-MCAO; this may be through decreasing the expression of STAT1, which influences the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway that may inhibit apoptosis to relieve neurological impairment.


Association of a Dietary Score with Incident Type 2 Diabetes: The Dietary-Based Diabetes-Risk Score (DDS).
Strong evidence supports that dietary modifications may decrease incident type 2 diabetes mellitus (T2DM). Numerous diabetes risk models/scores have been developed, but most do not rely specifically on dietary variables or do not fully capture the overall dietary pattern. We prospectively assessed the association of a dietary-based diabetes-risk score (DDS), which integrates optimal food patterns, with the risk of developing T2DM in the SUN ("Seguimiento Universidad de Navarra") longitudinal study. We assessed 17,292 participants initially free of diabetes, followed-up for a mean of 9.2 years. A validated 136-item FFQ was administered at baseline. Taking into account previous literature, the DDS positively weighted vegetables, fruit, whole cereals, nuts, coffee, low-fat dairy, fiber, PUFA, and alcohol in moderate amounts; while it negatively weighted red meat, processed meats and sugar-sweetened beverages. Energy-adjusted quintiles of each item (with exception of moderate alcohol consumption that received either 0 or 5 points) were used to build the DDS (maximum: 60 points). Incident T2DM was confirmed through additional detailed questionnaires and review of medical records of participants. We used Cox proportional hazards models adjusted for socio-demographic and anthropometric parameters, health-related habits, and clinical variables to estimate hazard ratios (HR) of T2DM. We observed 143 T2DM confirmed cases during follow-up. Better baseline conformity with the DDS was associated with lower incidence of T2DM (multivariable-adjusted HR for intermediate (25-39 points) vs. low (11-24) category 0.43 [95% confidence interval (CI) 0.21, 0.89]; and for high (40-60) vs. low category 0.32 [95% CI: 0.14, 0.69]; p for linear trend: 0.019). The DDS, a simple score exclusively based on dietary components, showed a strong inverse association with incident T2DM. This score may be applicable in clinical practice to improve dietary habits of subjects at high risk of T2DM and also as an educational tool for laypeople to help them in self-assessing their future risk for developing diabetes.


Development of an assessment to identify play behaviours that discriminate between the play of typical preschoolers and preschoolers with pre-academic problems.
Occupational therapists regard play as the primary occupation of childhood. However, many authors of play assessments have viewed play either as a functional outcome of other skills or as an indication of the child's developmental level. While such views of play are valid, these approaches to play are broad and do not fully consider the cognitive value of play. A study was undertaken with 82 preschoolers to see if a new play assessment which considers cognitive play skills, called the Child-initiated Pretend Play Assessment, (ChiPPA), possessed acceptable inter-rater reliability, and could discriminate between the play of typically developing preschoolers and preschoolers with pre-academic problems. This assessment evaluates preschoolers' elaborate imaginative actions, number of imitative actions, and number of object substitutions. The ChiPPA was found to have excellent inter-rater reliability and did discriminate between children who were typically developing and children who experienced pre-academic problems. In particular, the elaborateness of a child's play actions and the child's ability to substitute objects were strong discriminators of preschoolers with and without pre-academic problems. Three play profiles which emerged from the research are discussed.


Multicenter validation of the analytical accuracy of Salmonella PCR: towards an international standard.
As part of a major international project for the validation and standardization of PCR for detection of five major food-borne pathogens, four primer sets specific for Salmonella species were evaluated in-house for their analytical accuracy (selectivity and detection limit) in identifying 43 Salmonella spp. and 47 non-Salmonella strains. The most selective primer set was found to be 139-141 (K. Rahn, S. A. De Grandis, R. C. Clarke, S. A. McEwen, J. E. Galán, C. Ginocchio, R. Curtiss III, and C. L. Gyles, Mol. Cell. Probes 6:271-279, 1992), which targets the invA gene. An extended determination of selectivity by using 364 strains showed that the inclusivity was 99.6% and the exclusivity was 100% for the invA primer set. To indicate possible PCR inhibitors derived from the sample DNA, an internal amplification control (IAC), which was coamplified with the invA target gene, was constructed. In the presence of 300 DNA copies of the IAC, the detection probability for primer set 139-141 was found to be 100% when a cell suspension containing 10(4) CFU/ml was used as the template in the PCR (50 CFU per reaction). The primer set was further validated in an international collaborative study that included 16 participating laboratories. Analysis with 28 coded ("blind") DNA samples revealed an analytical accuracy of 98%. Thus, a simple PCR assay that is specific for Salmonella spp. and amplifies a chromosomal DNA fragment detected by gel electrophoresis was established through extensive validation and is proposed as an international standard. This study addresses the increasing demand of quality assurance laboratories for standard diagnostic methods and presents findings that can facilitate the international comparison and exchange of epidemiological data.


(1)H, (13)C and (15)N assignments of EGF domains 4 to 7 of human Notch-1.
The Notch pathway is a core cell-cell signaling system in Metazoa which plays a key role in development and adult homeostasis. Whereas most Notch structural biology research has focused on the negative regulatory region and the intracellular domain, relatively little structural information is available for the extracellular part of human Notch-1 (hN-1) which mediates ligand recognition. This region consists of 36 epidermal growth factor-like (EGF) domains, many of which contain a calcium-binding consensus sequence. The calcium-binding site in each case is located within the N-terminal portion of the domain, and is associated with both intra- and inter-domain rigidity. The absence of calcium-binding sites in EGF6, EGF10 and EGF22, however, suggests that these domains might represent regions of flexibility in the receptor which could influence the cell-surface architecture (usually depicted as an extended rod projecting from the cell surface). To probe this, we have purified a quadruple-domain construct from hN-1, in which the non-calcium-binding EGF6 is flanked by EGF4-5 and EGF7. Here, we report (1)H, (13)C and (15)N resonance assignments for this four-domain 157 amino acid construct. The assignments presented here are the prerequisite for a detailed study of the structure and dynamics of this region of the Notch receptor.


[Dutch computer domestication, 1975-1990].
A computer seems an indispensable tool among twenty-first century households. Computers however, did not come as manna from heaven. The domestication and appropriation of computers in Dutch households was a result of activities by various intermediary actors. Computers became household commodities only gradually. Technophile computer hobbyists imported the first computers into the Netherlands from the USA, and started small businesses from 1975 onwards. They developed a social network in which computer technology was made available for use by individuals. This network extended itself via shops, clubs, magazines, and other means of acquiring and exchanging computer hard- and software. Hobbyist culture established the software-copying habits of private computer users as well as their ambivalence to commercial software. They also made the computer into a game machine. Under the impulse of a national policy that aimed at transforming society into an 'Information Society', clubs and other actors extended their activities and tailored them to this new agenda. Hobby clubs presented themselves as consumer organizations and transformed into intermediary actors that filled the gap between suppliers and a growing group of users. They worked hard to give meaning to (proper) use of computers. A second impulse to the increasing use of computers in the household came from so-called 'private-PC' projects in the late 1980s. In these projects employers financially aided employees in purchasing their own private PCs'. The initially important intermediary actors such as hobby clubs lost control and the agenda for personal computers was shifted to interoperability with office equipment. IBM compatible PC's flooded the households. In the household the new equipment blended with the established uses, such as gaming. The copying habits together with the PC standard created a risky combination in which computer viruses could spread easily. New roles arose for intermediary actors in guiding and educating computer users. The activities of intermediaries had a lasting influence on contemporary computer use and user preferences. Technical choices and the nature of Dutch computer use in households can be explained by analyzing the historical developments of intermediaries and users.