473 research outputs found
Elastic properties of highly anisotropic thin poly(propylene) foams
In this letter, elastic properties of highly anisotropic cellular
poly(propylene) films are reported. The material shows peculiar elastic
properties compared to other foams in the literature. The data is displayed as
the relative Young's modulus versus relative density .
Almost all the data from the literature are located on the region
with . The introduced material on the
other hand have lower relative Young's modulus at high relative densities,
An AP-1/clathrin coat plays a novel and essential role in forming the Weibel-Palade bodies of endothelial cells
Clathrin provides an external scaffold to form small 50–100-nm transport vesicles. In contrast, formation of much larger dense-cored secretory granules is driven by selective aggregation of internal cargo at the trans-Golgi network; the only known role of clathrin in dense-cored secretory granules formation is to remove missorted proteins by small, coated vesicles during maturation of these spherical organelles. The formation of Weibel-Palade bodies (WPBs) is also cargo driven, but these are cigar-shaped organelles up to 5 μm long. We hypothesized that a cytoplasmic coat might be required to make these very different structures, and we found that new and forming WPBs are extensively, sometimes completely, coated. Overexpression of an AP-180 truncation mutant that prevents clathrin coat formation or reduced AP-1 expression by small interfering RNA both block WPB formation. We propose that, in contrast to other secretory granules, cargo aggregation alone is not sufficient to form immature WPBs and that an external scaffold that contains AP-1 and clathrin is essential
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A randomized controlled trial of social cognition and interaction training for persons with first episode psychosis in Hong Kong
Data availability statement: The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Supplementary material: The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fpsyt.2023.1098662/full#supplementary-materialCopyright © 2023 Lo, Lui, Law, Roberts and Siu. . Social cognitive impairment is a core limiting factor of functional recovery among persons with first episode psychosis (FEP). Social Cognition and Interaction Training (SCIT) is a group-based, manualized training with demonstrated evidence in improving social cognitive performance among people with schizophrenia. However, there are few studies on the effect of SCIT for people with FEP and for people in non-Western societies. This study evaluated the feasibility, acceptability and initial effectiveness of the locally-adapted SCIT in improving social cognitive functioning in Chinese people with FEP. The SCIT was delivered two sessions per week over a 10-weeks period, each session lasted for 60–90 min. A total of 72 subjects with FEP were recruited from an outpatient clinic and randomized to conventional rehabilitation (“Rehab”) and experimental (“SCIT and Rehab”) groups. Primary outcome measures included four social cognitive domains including emotion perception, theory-of-mind, attributional bias and jumping-to-conclusion, and secondary measures included neurocognition, social competence and quality of life. Participants were assessed at baseline, post-treatment, and 3-months post-treatment. Repeated measures ANCOVAs, with baseline scores as covariates, were used to compare the group differences in various outcomes across time. The results showed that the SCIT was well-accepted, with a satisfactory completion rate and subjective ratings of relevance in the experimental group. Moreover, treatment completers (n = 28) showed evidence of an advantage, over conventional group (n = 31), in reduced attributional bias and jumping-to-conclusions at treatment completion, lending initial support for the SCIT in Chinese people with FEP. Future research should address the limitations of this study, using more refined outcome measurements and higher treatment intensity of the SCIT
Pulmonary effects and disposition of luteolin and Artemisia afra extracts in isolated perfused lungs
ETHNOPHARMACOLOGICAL RELEVANCE: Artemisia afra (Asteraceae) is a traditional medicinal plant frequently used in steam inhalation form to treat respiratory conditions.
AIM OF THE STUDY: Quantify luteolin content in Artemisia afra dried crude and aqueous extract. Evaluate the pulmonary effects of Artemisia afra steam inhalation, nebulized Artemisia afra extract and luteolin in isolated perfused lungs (IPL). Evaluate the pulmonary disposition of intravenously administered luteolin. MATERIALS AND METHODS: HPLC was used to quantify luteolin in Artemisia afra extracts. A modified version of the IPL was used to determine the effects of Artemisia afra steam inhalation, nebulized luteolin, and nebulized aqueous leaf extract on lung function, as well as the pulmonary disposition of IV luteolin.
RESULTS: Artemisia afra extract contained significantly higher luteolin levels than the crude dried leaves. Inhaled Artemisia afra steam, and nebulized luteolin, and Artemisia afra extract and IV luteolin produced significant dose-dependent improvements in lung function, with nebulized Artemisia afra producing the greatest improvements. Nebulisation with Artemisia afra extract yielded higher quantities of luteolin than luteolin nebulisation.
CONCLUSION: Results verify the traditional use of inhalation of Artemisia afra steam, although nebulized luteolin and aqueous extract are better alternatives. Luteolin significantly contributes to the broncho-dilatory effects of Artemisia afra.Web of Scienc
APOBEC-Mediated Cytosine Deamination Links PIK3CA Helical Domain Mutations to Human Papillomavirus-Driven Tumor Development
APOBEC3B cytosine deaminase activity has recently emerged as a significant mutagenic factor in human cancer. APOBEC activity is induced in virally infected cells, and APOBEC signature mutations occur at high frequency in cervical cancers (CESC), over 99% of which are caused by human papillomavirus (HPV). We tested whether APOBEC-mediated mutagenesis is particularly important in HPV-associated tumors by comparing the exomes of HPV+ and HPV- head and neck squamous cell carcinomas (HNSCCs) sequenced by The Cancer Genome Atlas project. As expected, HPV- HNSCC displays a smoking-associated mutational signature, whereas our data suggest that reduced exposure to exogenous carcinogens in HPV+ HNSCC creates a selective pressure that favors emergence of tumors with APOBEC-mediated driver mutations. Finally, we provide evidence that APOBEC activity is responsible for the?generation of helical domain hot spot mutations in the PIK3CA gene across multiple cancers. Our?findings implicate APOBEC activity as a key driver?of PIK3CA mutagenesis and HPV-induced transformation
Clathrin-mediated post-fusion membrane retrieval influences the exocytic mode of endothelial Weibel-Palade bodies.
Weibel-Palade bodies (WPBs), the storage organelles of endothelial cells, are essential to normal haemostatic and inflammatory responses. Their major constituent protein is von Willebrand factor (VWF) which, following stimulation with secretagogues, is released into the blood vessel lumen as large platelet-catching strings. This exocytosis changes the protein composition of the cell surface and also results in a net increase in the amount of plasma membrane. Compensatory endocytosis is thought to limit changes in cell size and retrieve fusion machinery and other misplaced integral membrane proteins following exocytosis; however, little is known about the extent, timing, mechanism and precise function of compensatory endocytosis in endothelial cells. Using biochemical assays, live-cell imaging and correlative spinning-disk microscopy and transmission electron microscopy assays we provide the first in-depth high-resolution characterisation of this process. We provide a model of compensatory endocytosis based on rapid clathrin- and dynamin-mediated retrieval. Inhibition of this process results in a change of exocytic mode: WPBs then fuse with previously fused WPBs rather than the plasma membrane, leading, in turn, to the formation of structurally impaired tangled VWF strings.This article has an associated First Person interview with the first authors of the paper
Attention Reshapes Center-Surround Receptive Field Structure in Macaque Cortical Area MT
Directing spatial attention to a location inside the classical receptive field (cRF) of a neuron in macaque medial temporal area (MT) shifts the center of the cRF toward the attended location. Here we investigate the influence of spatial attention on the profile of the inhibitory surround present in many MT neurons. Two monkeys attended to the fixation point or to 1 of 2 random dot patterns (RDPs) placed inside or next to the cRF, whereas a third RDP (the probe) was briefly presented in quick succession across the cRF and surround. The probe presentation responses were used to compute a map of the excitatory receptive field and its inhibitory surround. Attention systematically reshapes the receptive field profile, independently shifting both center and surround toward the attended location. Furthermore, cRF size is changed as a function of relative distance to the attentional focus: attention inside the cRF shrinks it, whereas directing attention next to the cRF expands it. In addition, we find systematic changes in surround inhibition and cRF amplitude. This nonmultiplicative push–pull modulation of the receptive field's center-surround structure optimizes processing at and near the attentional focus to strengthen the representation of the attended stimulus while reducing influences from distractors
CogStack - experiences of deploying integrated information retrieval and extraction services in a large National Health Service Foundation Trust hospital.
BACKGROUND: Traditional health information systems are generally devised to support clinical data collection at the point of care. However, as the significance of the modern information economy expands in scope and permeates the healthcare domain, there is an increasing urgency for healthcare organisations to offer information systems that address the expectations of clinicians, researchers and the business intelligence community alike. Amongst other emergent requirements, the principal unmet need might be defined as the 3R principle (right data, right place, right time) to address deficiencies in organisational data flow while retaining the strict information governance policies that apply within the UK National Health Service (NHS). Here, we describe our work on creating and deploying a low cost structured and unstructured information retrieval and extraction architecture within King's College Hospital, the management of governance concerns and the associated use cases and cost saving opportunities that such components present. RESULTS: To date, our CogStack architecture has processed over 300 million lines of clinical data, making it available for internal service improvement projects at King's College London. On generated data designed to simulate real world clinical text, our de-identification algorithm achieved up to 94% precision and up to 96% recall. CONCLUSION: We describe a toolkit which we feel is of huge value to the UK (and beyond) healthcare community. It is the only open source, easily deployable solution designed for the UK healthcare environment, in a landscape populated by expensive proprietary systems. Solutions such as these provide a crucial foundation for the genomic revolution in medicine
A phase I, open-label, randomized crossover study to assess the effect of dosing of the MEK 1/2 inhibitor Selumetinib (AZD6244; ARRY-142866) in the presence and absence of food in patients with advanced solid tumors
<p><b>Purpose:</b> This Phase I study assessed whether food influences the rate and extent of selumetinib absorption in patients with advanced solid malignancies and determined the safety, tolerability, and pharmacokinetic (PK) profile of selumetinib and its active metabolite N-desmethyl-selumetinib in fed and fasted states.</p>
<p><b>Methods:</b> A single dose of 75 mg selumetinib was to be taken with food on Day 1 followed by a single dose of 75 mg after fasting for at least 10 h on Day 8, or vice versa, followed by twice daily dosing of 75 mg selumetinib from Day 10. Plasma concentrations and PK parameters were determined on Days 1 and 8. Patients could continue to receive selumetinib for as long as they benefitted from treatment.</p>
<p><b>Results:</b> In total, 31 patients were randomized to receive selumetinib; 15 to fed/fasted sequence and 16 to fasted/fed sequence. Comprehensive PK sampling was performed on 11 and 10 patients, respectively. The geometric least-squares means of C<sub>max</sub> and AUC for selumetinib were reduced by 62% (ratio 0.38 90% CI 0.29, 0.50) and 19% (ratio 0.81 90% CI 0.74, 0.88), respectively, under fed compared with fasting conditions. The rate of absorption (t<sub>max</sub>) of selumetinib (fed) was delayed by approximately 2.5 h (median). The food effect was also observed for the active metabolite N-desmethyl-selumetinib. Selumetinib was well tolerated.</p>
<p><b>Conclusions:</b> The presence of food decreased the extent of absorption of selumetinib. It is recommended that for further clinical studies, selumetinib be taken on an empty stomach. Selumetinib demonstrated an acceptable safety profile in the advanced cancer population.</p>
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