528 research outputs found
Observation of sub-Doppler absorption in the /Lambda-type three-level Doppler-broadened cesium system
Thanks to the atomic coherence in coupling laser driven atomic system,
sub-Doppler absorption has been observed in Doppler-broadened cesium vapor cell
via the /Lambda-type three-level scheme. The linewidth of the sub-Doppler
absorption peak become narrower while the frequency detuning of coupling laser
increases. The results are in agreement with the theoretical prediction by G.
Vemuri et al.[PRA,Vol.53(1996) p.2842].Comment: 12 pages, 5 figures, to appear on Applied Physics
An Unusual Suspect in Cocaine Addiction
Development of drug addiction is extremely complex, but its initiation can be as simple as the flip-flop of glutamatergic receptor subtypes triggered by an “unusual” type of NMDA receptors, as suggested by Yuan et al. (2013) in this issue of Neuron
The role of the neutrophil FcÎł receptor I (CD64) index in diagnosing spontaneous bacterial peritonitis in cirrhotic patients
SummaryObjectiveTo investigate the role of the neutrophil Fcγ receptor I (CD64) index in the diagnosis of spontaneous bacterial peritonitis (SBP) in cirrhotic patients.MethodsA total of 123 cirrhotic patients with ascites who fulfilled the inclusion criteria were enrolled in this study. Ascites and blood samples were collected; the polymorphonuclear neutrophil (PMN) count, bacterial culture, and related laboratory tests were performed. The CD64 index was determined for each sample using flow cytometry.ResultsThe neutrophil CD64 index results were significantly higher in cirrhotic patients with SBP than in those without SBP (p<0.001). There was a positive correlation between the neutrophil CD64 index and the PMN count in ascites. In the receiver operating characteristic curve (ROC) analysis, the area under the curve (AUC) was 0.894 (95% confidence interval 0.823–0.964, p<0.001). The optimal cut-off value for the neutrophil CD64 index was 2.02. The sensitivity and specificity of the neutrophil CD64 index for cirrhotic patients with SBP were 80.49% and 93.90%, respectively. The elevated neutrophil CD64 index was down-regulated by antibiotic therapy (p=0.002).ConclusionsThe neutrophil CD64 index could be used as a sensitive and specific indicator for the diagnosis of SBP in cirrhotic patients with ascites and is also modulated by antibiotic therapy
Expression of CD39 on FoxP3+ T regulatory cells correlates with progression of HBV infection
BACKGROUND: Although it is known that regulatory T cells (Tregs) can suppress the function of effector T cells, and may contribute to impaired immune response, the precise role of Tregs during the course of hepatitis B virus (HBV) infection remains to be elucidated. A newly identified subset of the CD4(+)Foxp3(+ )Tregs, the CD39(+ )Tregs, has been associated with viral infections and autoimmune diseases. Therefore, we hypothesized that this discrete Treg subset may contribute to the chronic infection of HBV. RESULTS: Initial characterization studies of healthy peripheral CD39(+)FoxP3(+)CD4(+ )T cells revealed that the majority were CD45RA(- )Treg cells. Subsequent analysis of HBV-infected patients (38 asymptomatic HBV carriers (AsCs), 37 chronic active hepatitis B (CAH), 29 HBV-associated acute-on-chronic liver failure (ACLF)) and healthy individuals (25 controls) was conducted to assess association with HBV copy number and the liver injury marker alanine aminotransferase (ALT). A higher percentage of CD39(+ )Tregs was detected within the population of FoxP3(+)CD4(+ )T cells in peripheral blood of AsCs patients. Moreover, the percentage of CD39(+ )Tregs was significantly less in CAH and ACLF patients. The increased proportions of circulating CD39(+ )Tregs were positively correlated with serum viral load, but inversely correlated with serum ALT level. CONCLUSION: These findings not only suggest that CD39(+ )Treg cells may be involved in HBV disease progression but also identify CD39(+ )Tregs as a dynamic immune regulatory cell population that may represent a new target of immunomodulatory therapeutic interventions
Gene expression and biological processes influenced by deletion of Stat3 in pulmonary type II epithelial cells
<p>Abstract</p> <p>Background</p> <p>The signal transducer and activator of transcription 3 (STAT3) mediates gene expression in response to numerous growth factors and cytokines, playing an important role in many cellular processes. To better understand the molecular mechanisms by which <it>Stat3 </it>influences gene expression in the lung, the effect of pulmonary epithelial cell specific deletion of <it>Stat3 </it>on genome wide mRNA expression profiling was assessed. Differentially expressed genes were identified from Affymetrix Murine GeneChips analysis and subjected to gene ontology classification, promoter analysis, pathway mapping and literature mining.</p> <p>Results</p> <p>Total of 791 mRNAs were significantly increased and 314 mRNAs were decreased in response to the deletion of <it>Stat3</it><sup>Δ/Δ </sup>in the lung. STAT is the most enriched cis-elements in the promoter regions of those differentially expressed genes. Deletion of <it>Stat3 </it>induced genes influencing protein metabolism, transport, chemotaxis and apoptosis and decreased the expression of genes mediating lipid synthesis and metabolism. Expression of <it>Srebf1 </it>and <it>2</it>, genes encoding key regulators of fatty acid and steroid biosynthesis, was decreased in type II cells from the <it>Stat3</it><sup>Δ/Δ </sup>mice, consistent with the observation that lung surfactant phospholipids content was decreased. <it>Stat3 </it>influenced both pro- and anti-apoptotic pathways that determine cell death or survival. <it>Akt</it>, a potential transcriptional target of <it>Stat3</it>, was identified as an important participant in <it>Stat3 </it>mediated pathways including Jak-Stat signaling, apoptosis, Mapk signaling, cholesterol and fatty acid biosynthesis.</p> <p>Conclusion</p> <p>Deletion of <it>Stat3 </it>from type II epithelial cells altered the expression of genes regulating diverse cellular processes, including cell growth, apoptosis and lipid metabolism. Pathway analysis indicates that STAT3 regulates cellular homeostasis through a complex regulatory network that likely enhances alveolar epithelial cell survival and surfactant/lipid synthesis, necessary for the protection of the lung during injury.</p
Cross-view Semantic Alignment for Livestreaming Product Recognition
Live commerce is the act of selling products online through live streaming.
The customer's diverse demands for online products introduce more challenges to
Livestreaming Product Recognition. Previous works have primarily focused on
fashion clothing data or utilize single-modal input, which does not reflect the
real-world scenario where multimodal data from various categories are present.
In this paper, we present LPR4M, a large-scale multimodal dataset that covers
34 categories, comprises 3 modalities (image, video, and text), and is 50x
larger than the largest publicly available dataset. LPR4M contains diverse
videos and noise modality pairs while exhibiting a long-tailed distribution,
resembling real-world problems. Moreover, a cRoss-vIew semantiC alignmEnt
(RICE) model is proposed to learn discriminative instance features from the
image and video views of the products. This is achieved through instance-level
contrastive learning and cross-view patch-level feature propagation. A novel
Patch Feature Reconstruction loss is proposed to penalize the semantic
misalignment between cross-view patches. Extensive experiments demonstrate the
effectiveness of RICE and provide insights into the importance of dataset
diversity and expressivity. The dataset and code are available at
https://github.com/adxcreative/RICEComment: Accepted to ICCV202
Cross-cultural validation of the Health Care Provider HIV/AIDS Stigma Scale (HPASS) in China
The study aimed to validate the Health Care Provider HIV/AIDS Stigma Scale among medical staff in China. The validation was conducted in four steps from March to December 2017: translation and back-translation; content validity test with six experts; test–retest reliability testing with 63 medical staff with 2 weeks interval; and structural validation with 349 medical staff from 52 hospitals with a convenience sample,using exploratory factor analysis,including principal component analysis and varimax rotation. The scale content validity index average was 0.88, while for test–retest reliability, the ICC was 0.87. Three factors of “discrimination”, “prejudice” and “stereotype” with 16 items were extracted and explained 59.61% variance. The Cronbach’s alpha value for the total scale was of 0.88, and for the three factors, the values were 0.89, 0.86 and 0.74, respectively. The discrimination factor showed identical means between Canadian medical students and Chinese medical staff, while the prejudice and stereotype factors had higher mean scores in the Chinese sample. The three-factor structure of Health Care Provider HIV/AIDS Stigma Scale was confirmed in Chinese medical staff with a simpler solution. This could provide a basis for trans-cultural application and comparison
- …