868 research outputs found
Expression Pattern of Cyclooxygenase-2 in Normal Rat Epidermis and Pilosebaceous Unit during Hair Cycle
As an important member of the cyclooxygenase isoenzymes, cyclooxygenase-2 (COX-2) mainly catalyzes the first two steps in prostanoid synthesis. In mammalian animals, although COX-2 was thought to be rarely expressed in most normal tissues and was usually upregulated in a variety of epithelial tumors and inflammatory reactions, recently it was reported that COX-2 could localize in the epidermis as well as the pilosebaceous unit of the normal human and mouse skin. Until now, the function of COX-2 in normal skin has remained unknown. To investigate the possible roles of COX-2 in normal skin by RT-PCR and immunochemistry, we studied the expression pattern of COX-2 in hair cycle of the normal rat skin. The expression of COX-2 mRNA was detected in normal rat skin sample and was related to the hair follicle cycle. When the hair cycle entered catagen and telogen, COX-2 mRNA transcription in skin increased significantly. Furthermore, the location of COX-2 immunoreactivity showed that COX-2 protein is mainly concentrated in the epidermis and pilosebaceous unit. In the stratified epidermis, the strong COX-2 protein expression was detected in the suprabasal layers of epidermis in anagen and declined in catagen and telogen. In hair follicle, COX-2 protein was obviously expressed in the outer root sheath of the anagen hair follicle, and was barely detectable in catagen as well as telogen. In the sebaceous gland, the COX-2 protein expression became more intense in catagen and telogen, with an increase in sebaceous gland size. Our results suggested that COX-2 was not specific to some abnormal tissues and was indeed involved in the normal physiology of rat skin, such as the differentiation of epidermis, the morphogenesis of the hair follicle, the transformation of hair cycle stages, and the lipid production of the sebaceous gland
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Functional variant of the carboxypeptidase M (CPM) gene may affect silica-related pneumoconiosis susceptibility by its expression: a multistage case-control study.
ObjectivesIn a genome-wide association study, we discovered chromosome 12q15 (defined as rs73329476) as a silica-related pneumoconiosis susceptibility region. However, the causal variants in this region have not yet been reported.MethodsWe systematically screened eight potentially functional single-neucleotide polymorphism (SNPs) in the genes near rs73329476 (carboxypeptidase M (CPM) and cleavage and polyadenylation specific factor 6 (CPSF6)) in a case-control study including 177 cases with silicosis and 204 healthy controls, matched to cases with years of silica dust exposure. We evaluated the associations between these eight SNPs and the development of silicosis. Luciferase reporter gene assays were performed to test the effects of selected SNP on the activity of CPM in the promoter. In addition, a two-stage case-control study was performed to investigate the expression differences of the two genes in peripheral blood leucocytes from a total of 64 cases with silicosis and 64 healthy controls with similar years of silica dust exposure as the cases.ResultsWe found a strong association between the mutant rs12812500 G allele and the susceptibility of silicosis (OR=1.45, 95% CI 1.03 to 2.04, p=0.034), while luciferase reporter gene assays indicated that the mutant G allele of rs12812500 is strongly associated with increased luciferase levels compared with the wild-type C allele (p<0.01). Moreover, the mRNA (peripheral blood leucocytes) expression of the CPM gene was significantly higher in subjects with silicosis compared with healthy controls.ConclusionsThe rs12812500 variant of the CPM gene may increase silicosis susceptibility by affecting the expression of CPM, which may contribute to silicosis susceptibility with biological plausibility
Towards Better Entity Linking with Multi-View Enhanced Distillation
Dense retrieval is widely used for entity linking to retrieve entities from
large-scale knowledge bases. Mainstream techniques are based on a dual-encoder
framework, which encodes mentions and entities independently and calculates
their relevances via rough interaction metrics, resulting in difficulty in
explicitly modeling multiple mention-relevant parts within entities to match
divergent mentions. Aiming at learning entity representations that can match
divergent mentions, this paper proposes a Multi-View Enhanced Distillation
(MVD) framework, which can effectively transfer knowledge of multiple
fine-grained and mention-relevant parts within entities from cross-encoders to
dual-encoders. Each entity is split into multiple views to avoid irrelevant
information being over-squashed into the mention-relevant view. We further
design cross-alignment and self-alignment mechanisms for this framework to
facilitate fine-grained knowledge distillation from the teacher model to the
student model. Meanwhile, we reserve a global-view that embeds the entity as a
whole to prevent dispersal of uniform information. Experiments show our method
achieves state-of-the-art performance on several entity linking benchmarks.Comment: Accepted by ACL 2023 Main Conferenc
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Brown Fat Paucity Due to Impaired BMP Signaling Induces Compensatory Browning of White Fat
Summary Maintenance of body temperature is essential for survival of homeotherms. Brown adipose tissue (BAT) is a specialized fat tissue that is dedicated to thermoregulation1. Due to its remarkable capacity to dissipate stored energy and its demonstrated presence in adult humans2-5, BAT holds great promise for the treatment of obesity and metabolic syndrome1. Rodent data suggest the existence of two types of brown fat cells: the constitutive BAT (cBAT), which is of embryonic origin and anatomically located in the interscapular region of mice, and the recruitable BAT (rBAT) that resides within white adipose tissue (WAT)6 and skeletal muscle7, that has alternatively been called beige8, brite9, or inducible BAT10. Bone morphogenetic proteins (BMPs) regulate the formation and thermogenic activity of BAT10-12. We here provide evidence for a systemically active regulatory mechanism that serves to control whole body BAT-activity for thermoregulation and energy homeostasis. Genetic ablation of type 1A BMP-receptor (Bmpr1A) in brown adipogenic progenitor cells leads to a severe paucity of cBAT. This in turn increases sympathetic input to WAT, thereby promoting the formation of rBAT within white fat depots. This previously unknown compensatory mechanism, aimed at restoring total brown fat-mediated thermogenic capacity in the body, is sufficient to maintain normal temperature homeostasis and resistance to diet-induced obesity. These data suggest an important physiological cross-talk between the constitutive and recruitable brown fat cells. This sophisticated regulatory mechanism of body temperature may participate in the control of energy balance and metabolic disease
Expression of a LINE-1 endonuclease variant in gastric cancer: its association with clinicopathological parameters
BACKGROUND: Long interspersed nuclear element-1 (LINE-1 or L1), the most abundant and only autonomously active family of non-LTR retrotransposons in the human genome, expressed not only in the germ lines but also in somatic tissues. It contributes to genetic instability, aging, and age-related diseases, such as cancer. Our previous study identified in human gastric adenocarcinoma an upregulated transcript GCRG213, which shared 88% homology with human L1 sequence and contained a putative conserved apurinic/apyrimidinic endonucleas1 domain. METHODS: Immunohistochemistry was carried out by using a monoclonal mouse anti-human GCRG213 protein (GCRG213p) antibody produced in our laboratory, on tissue microarray constructed with specimens from 175 gastric adenocarcinoma patients. The correlation between GCRG213p expression and patient clinicopathological parameters was evaluated. GCRG213p expression in gastric cancer cell lines were studied using Western blotting analysis. L1 promoter methylation status of gastric cancer cells was tested using methylation-specific PCR. BLASTP was used at the NCBI Blast server to identify GCRG213p sequence to any alignments in the Protein Data Bank databases. RESULTS: Most primary gastric cancer, lymph node metastases and gastric intestinal metaplasia glands showed positive GCRG213p immunoreactivity. High GCRG213p immunostaining score in the primary gastric cancer was positively correlated with tumor differentiation (well differentiated, p = 0.001), Lauren’s classification (intestinal type, p < 0.05) and a late age onset of gastric adenocarcinoma (≥65 yrs; p < 0.05). GCRG213p expression has no association with other clinicopathological parameters, including survival. Western blotting analysis of GCRG213p expression in gastric cancer cells indicated that GCRG213p level was higher in gastric cancer cell lines than in human normal gastric epithelium immortalized cell line GES-1. Partial methylation of L1 in gastric cancer cells was confirmed by methylation-specific PCR. BLASTP program analysis revealed that GCRG213p peptide shared 83.0% alignment with the C-terminal region of L1 endonuclease (L1-EN). GCRG213p sequence possesses the important residues that compose the conserved features of L1-EN. CONCLUSIONS: GCRG213p could be a variant of L1-EN, a functional member of L1-EN family. Overexpression of GCRG213p is common in both primary gastric cancer and lymph node metastasis. These findings provide evidence of somatic L1 expression in gastric cancer, and its potential consequences in the form of tumor
Liver lobe-based magnetic resonance diffusion-weighted imaging using multiple b values in patients with hepatitis B-related liver cirrhosis: association with the liver disease severity according to the Child-Pugh class
OBJECTIVE: To determine the associations of liver lobe-based magnetic resonance diffusion-weighted imaging findings using multiple b values with the presence and Child-Pugh class of cirrhosis in patients with hepatitis B. METHODS: Seventy-four cirrhotic patients with hepatitis B and 25 healthy volunteers underwent diffusion-weighted imaging using b values of 0, 500, 800 and 1000 sec/mm2. The apparent diffusion coefficients of individual liver lobes for b(0,500), b(0,800) and b(0,1000) were derived from the signal intensity averaged across images obtained using b values of 0 and 500 sec/mm2, 0 and 800 sec/mm2, or 0 and 1000 sec/mm2, respectively, and were statistically analyzed to evaluate cirrhosis. RESULTS: The apparent diffusion coefficients for b(0,500), b(0,800) and b(0,1000) inversely correlated with the Child-Pugh class in the left lateral liver lobe, the left medial liver lobe, the right liver lobe and the caudate lobe (r=-0.35 to -0.60, all p;0.05). Among these parameters, the apparent diffusion coefficient for b(0,500) in the left lateral liver lobe best differentiated normal from cirrhotic liver, with an area under the receiver operating characteristic curve of 0.989. The apparent diffusion coefficient for b(0,800) in the right liver lobe best distinguished Child-Pugh class A from B-C and A-B from C, with areas under the receiver operating characteristic curve of 0.732 and 0.747, respectively. CONCLUSION: Liver lobe-based apparent diffusion coefficients for b(0,500) and b(0,800) appear to be associated with the presence and Child-Pugh class of liver cirrhosis
Salvianolic acid B plays an anti-obesity role in high fat diet-induced obese mice by regulating the expression of mRNA, circRNA, and lncRNA
Background Adipose tissue plays a central role in obesity-related metabolic diseases such as type 2 diabetes. Salvianolic acid B (Sal B), a water-soluble ingredient derived from Salvia miltiorrhiza, has been shown to reduce obesity and obesity-related metabolic diseases by suppressing adipogenesis. However, the role of Sal B in white adipose tissue (WAT) is not yet clear. Methods Illumina Hiseq 4000 was used to study the effects of Sal B on the expression of long non-coding RNA (lncRNA) and circular RNA (circRNA) in epididymal white adipose tissue induced by a high fat diet in obese mice. Results RNA-Seq data showed that 234 lncRNAs, 19 circRNAs, and 132 mRNAs were differentially expressed in WAT under Sal B treatment. The up-regulated protein-coding genes in WAT of the Sal B-treated group were involved in the insulin resistance pathway, while the down-regulated genes mainly participated in the IL-17 signaling pathway. Other pathways may play an important role in the formation and differentiation of adipose tissue, such as B cell receptor signaling. Analysis of the lncRNA–mRNA network provides potential targets for lncRNAs in energy metabolism. We speculate that Sal B may serve as a potential therapeutic approach for obesity
Predicting potential microbe-disease associations with graph attention autoencoder, positive-unlabeled learning, and deep neural network
BackgroundMicrobes have dense linkages with human diseases. Balanced microorganisms protect human body against physiological disorders while unbalanced ones may cause diseases. Thus, identification of potential associations between microbes and diseases can contribute to the diagnosis and therapy of various complex diseases. Biological experiments for microbe–disease association (MDA) prediction are expensive, time-consuming, and labor-intensive.MethodsWe developed a computational MDA prediction method called GPUDMDA by combining graph attention autoencoder, positive-unlabeled learning, and deep neural network. First, GPUDMDA computes disease similarity and microbe similarity matrices by integrating their functional similarity and Gaussian association profile kernel similarity, respectively. Next, it learns the feature representation of each microbe–disease pair using graph attention autoencoder based on the obtained disease similarity and microbe similarity matrices. Third, it selects a few reliable negative MDAs based on positive-unlabeled learning. Finally, it takes the learned MDA features and the selected negative MDAs as inputs and designed a deep neural network to predict potential MDAs.ResultsGPUDMDA was compared with four state-of-the-art MDA identification models (i.e., MNNMDA, GATMDA, LRLSHMDA, and NTSHMDA) on the HMDAD and Disbiome databases under five-fold cross validations on microbes, diseases, and microbe-disease pairs. Under the three five-fold cross validations, GPUDMDA computed the best AUCs of 0.7121, 0.9454, and 0.9501 on the HMDAD database and 0.8372, 0.8908, and 0.8948 on the Disbiome database, respectively, outperforming the other four MDA prediction methods. Asthma is the most common chronic respiratory condition and affects ~339 million people worldwide. Inflammatory bowel disease is a class of globally chronic intestinal disease widely existed in the gut and gastrointestinal tract and extraintestinal organs of patients. Particularly, inflammatory bowel disease severely affects the growth and development of children. We used the proposed GPUDMDA method and found that Enterobacter hormaechei had potential associations with both asthma and inflammatory bowel disease and need further biological experimental validation.ConclusionThe proposed GPUDMDA demonstrated the powerful MDA prediction ability. We anticipate that GPUDMDA helps screen the therapeutic clues for microbe-related diseases
Amniotic fluid-derived mesenchymal stem cells as a novel therapeutic approach in the treatment of fulminant hepatic failure in rats
As a potential alternative treatment for terminal liver diseases, amniotic fluid derived mesenchymal stem cells (AFMSCs) have many advantages over other stem cells: avoiding much ethical controversy and decrease in both quantity and differentiation potential with age. However, the therapeutic role of AFMSC for fulminant hepatic failure (FHF) has not yet been clearly elucidated. Therefore, we investigated the reparation effects of transplanted AFMSCs in rats with FHF. AFMSCs were transplanted into injured liver via the portal vein in the rat FHF model. Therapeutic effect was evaluated after cell transfusion by histologic pathology, hepatic enzyme levels and animal survival. Cryostat sections were prepared and directly assessed for green fluorescent protein (GFP) expression and localization, and in vivo differentiation of AFMSC was confirmed by double-immunostaining analyses. Our results show that AFMSCs prevented liver failure and reduced mortality in rats with FHF. These animals also exhibited improved liver function and animals survival after injection with AFMSCs using GFP, we demonstrated that the engrafted cells and their progeny incorporated into injured livers and produced albumin. We found that AFMSCs transplantation modestly promoted the repair of FHF in rats. AFMSCs implanted in the injured liver may be a novel therapeutic approach in the treatment of FHF.Key words: Amniotic fluid-derived mesenchymal stem cells, fulminant hepatic failure, cell transplantation, treatment, hepatogenic differentiation
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