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1.
Nanoscale ; 16(5): 2185-2219, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38226715

RESUMO

MOF-based photoelectrocatalysis (PEC) using CO2 as an electron donor offers a green, clean, and extensible way to make hydrocarbon fuels under more tolerant conditions. Herein, basic principles of PEC reduction of CO2 and the preparation methods and characterization techniques of MOF-based materials are summarized. Furthermore, three applications of MOFs for improving the photoelectrocatalytic performance of CO2 reduction are described: (i) as photoelectrode alone; (ii) as a co-catalyst of semiconductor photoelectrode or as a substrate for loading dyes, quantum dots, and other co-catalysts; (iii) as one of the components of heterojunction structure. Challenges and future wave surrounding the development of robust PEC CO2 systems based on MOF materials are also discussed briefly.

2.
Sensors (Basel) ; 23(17)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37687814

RESUMO

This paper explores the potential for communication-efficient federated learning (FL) in modern distributed systems. FL is an emerging distributed machine learning technique that allows for the distributed training of a single machine learning model across multiple geographically distributed clients. This paper surveys the various approaches to communication-efficient FL, including model updates, compression techniques, resource management for the edge and cloud, and client selection. We also review the various optimization techniques associated with communication-efficient FL, such as compression schemes and structured updates. Finally, we highlight the current research challenges and discuss the potential future directions for communication-efficient FL.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-991435

RESUMO

Objective:To explore application of mixed teaching platform in the clinical practice teaching of the laboratory medicine in Children's hospitals.Methods:We constructed a mixed online and offline teaching platform based on the Laboratory Quality Management System (LQMS) in the Children's Hospital of Chongqing Medical University. The undergraduates from Batch 2016 ( n=15) and Batch 2018 ( n=12) of College of Laboratory Medicine of Chongqing Medical University were taken as control group and experimental group respectively. Traditional teaching method was adopted by the control group, and the mixed teaching method was adopted by the experimental group. The results of two groups' clinical practice assessment, rate of outstanding students (total score ≥ 90) and rate of satisfaction (score ≥ 90) were compared to evaluate the teaching effect. SPSS 17.0 was used to conduct t-test and Chi-square test. Results:The database of teaching platform includes 68 teaching cases, 198 pieces of courseware, 305 clinical cases and 3 036 atlases. The test bank has accumulated 4 657 tests, covering clinical laboratory, immunology, biochemistry, microbiology and blood transfusion. The results of students in experimental group were significantly better than those of the control group [the score of clinical practice assessment: (85.90±5.04) vs. (78.90±6.75)( P<0.05); rate of outstanding students: 33.3% (4/12) vs. 6.7% (1/15), P>0.05; rate of satisfaction: 86.7% (13/15) vs. 100.0% (12/12) ( P>0.05). Conclusion:The mixed online and offline teaching platform based on the LQMS is highly recognized by students and can significantly improve the effect of clinical practice teaching, which can provide typical medical case teaching at any time and make up for limited case type in children's hospital.

4.
Artigo em Inglês | MEDLINE | ID: mdl-35867363

RESUMO

Automatic rumor detection is critical for maintaining a healthy social media environment. The mainstream methods generally learn rich features from information cascades by modeling the cascade as a tree or graph structure where edges are built based on interactions between a tweet and retweets. Some psychology studies have empirically shown that users' various subjective factors always cause the uncertainty of interactions such as differences among interactive behavior activation thresholds or semantic relevancy. However, previous works model interactions by employing a simple fully connected layer on fixed edge weights in the graph and cannot reasonably describe this inherent uncertainty of complex interactions. In this article, inspired by the fuzzy theory, we propose a novel neuro-fuzzy method, fuzzy graph convolutional networks (FGCNs), to sufficiently understand uncertain interactions in the information cascade in a fuzzy perspective. Specifically, a new strategy of graph construction is first designed to convert each information cascade into a heterogeneous graph structure with the consideration of explicit interactive behaviors between a tweet and its retweet, as well as implicit interactive behaviors among retweets, enriching more structural clues in the graph. Then, we improve graph convolutional networks by incorporating edge fuzzification (EF) modules. The EFs adapt edge weights according to predefined membership to enhance message passing in the graph. The proposed model can provide a stronger relational inductive bias for expressing uncertain interactions and capture more discriminative and robust structural features for rumor detection. Extensive experiments demonstrate the effectiveness and superiority of FGCN on both rumor detection and early rumor detection.

5.
Radiology ; 299(3): 597-610, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33876972

RESUMO

Background Biliary obstruction leads to an increase in biliary pressure within the biliary system, which induces the morphologic adaptation of the biliary tree. Purpose To observe and to quantify the morphologic characteristics of the adaptation in a bile duct ligation rat model and verify it in patients with biliary atresia in a three-dimensional (3D) manner using x-ray phase-contrast CT. Materials and Methods A bile duct ligation model was induced in 40 male Sprague-Dawley rats, which were divided into five groups: the control group (no ligation) and groups 2, 4, 6, and 8 weeks after bile duct ligation (eight animals in each group). Liver tissue samples (approximately 1.8 cm in length and 1.3 cm in height) were imaged by using phase-contrast CT and compared with histologic analysis. With a combination of phase-contrast CT and 3D visualization technology, the entire biliary system and the intrahepatic vascular system were quantitatively analyzed according to downstream, midstream, and upstream domains based on bile duct volume, surface area, and other parameters. Additionally, liver explant tissues from 28 patients with biliary atresia were studied to determine the impact of biliary tract reconstruction. Results To offset the increased biliary pressure within the biliary system, the ductular reaction in the downstream, midstream, and upstream domains manifested as dilatation, spiderweb-like looping, and interconnected honeycomb-like patterns, respectively. The most severe ductular reaction occurred in the upstream domain, and the relative surface area (mean, 0.02 µm-1 ± 0.01, 0.04 µm-1 ± 0.01, 0.07 µm-1 ± 0.02, and 0.10 µm-1 ± 0.02 for the 2-8-week groups, respectively; P < .01 among the groups) and volume fraction of ductules (mean, 16.54% ± 4.62, 19.69% ± 6.41, 26.92% ± 5.82, and 38.34% ± 10.36 for the 2-8-week groups, respectively; P < .01 among the groups except between the 2- and 4-week groups [P = .062]) significantly increased over time. In patients with biliary atresia, it was observed that both fibrosis and proliferative ductules regressed after successful biliary tract reconstruction following Kasai portoenterostomy. Furthermore, ductular reaction was accompanied by a progressive increase in the arterial supply but a loss of portal blood supply. Conclusion X-ray phase-contrast CT with three-dimensional rendering of the biliary system in a bile duct ligation rat model provides key insights into ductular reaction or biliary self-adaptation triggered by increased biliary pressure. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Vannier and Wang in this issue.


Assuntos
Colestase/diagnóstico por imagem , Colestase/patologia , Imageamento Tridimensional/métodos , Fígado/diagnóstico por imagem , Fígado/patologia , Tomografia Computadorizada por Raios X/métodos , Animais , Sistema Biliar/diagnóstico por imagem , Modelos Animais de Doenças , Ligadura , Fígado/irrigação sanguínea , Masculino , Ratos , Ratos Sprague-Dawley
6.
PLoS One ; 13(5): e0197878, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29799865

RESUMO

An experimental model for postweaning diarrhea with enterotoxigenic Escherichia coli F4 (ETEC F4) was set up in piglets, and the efficacy of 1% chestnut-tannin extract in preventing diarrhea was subsequently assessed. In a first trial (infection model), 32 Swiss Large White piglets (age: 24 days; average BW: 7.8 ± 0.8 kg) were randomly assigned to two experimental groups (infected [INF], noninfected [NINF]). In a subsequent trial, 72 Swiss Large White piglets (age: 26 days; average BW: 7.4 ± 1.5 kg) were blocked by BW and assigned within block to four experimental groups: NINF-CO: not infected and fed a standard control starter diet (CO); INF-CO: infected and fed the CO diet; NINF-TA: not infected and fed the CO diet supplemented with 1% chestnut extract containing 54% of hydrolysable tannins (TA); and INF-TA: infected and fed the TA diet. Both diets (TA and CO) were formulated to be isocaloric and isoproteic and to meet or surpass the nutritional requirements. In both trials, four days after weaning, piglets assigned to the INF group received an oral suspension of ETEC F4. Fecal score, ETEC shedding in feces (only in trial 2), and growth performance traits were measured for the following 14 days post infection. In both trials, more than 50% of the INF piglets developed diarrhea within six days post infection. Tannins reduced (P < 0.05) the average fecal score, the percentage of piglets in diarrhea, and the duration of diarrhea, whereas feed intake and the average daily gain were unaffected.


Assuntos
Diarreia/tratamento farmacológico , Fagaceae/química , Taninos Hidrolisáveis/farmacologia , Desmame , Animais , Modelos Animais de Doenças , Taninos Hidrolisáveis/uso terapêutico , Suínos
7.
Genetics ; 205(2): 955-965, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27986804

RESUMO

The dwarf phenotype characterizes the smallest of rabbit breeds and is governed largely by the effects of a single dwarfing allele with an incompletely dominant effect on growth. Dwarf rabbits typically weigh under 1 kg and have altered craniofacial morphology. The dwarf allele is recessive lethal and dwarf homozygotes die within a few days of birth. The dwarf phenotype is expressed in heterozygous individuals and rabbits from dwarf breeds homozygous for the wild-type allele are normal, although smaller when compared to other breeds. Here, we show that the dwarf allele constitutes a ∼12.1 kb deletion overlapping the promoter region and first three exons of the HMGA2 gene leading to inactivation of this gene. HMGA2 has been frequently associated with variation in body size across species. Homozygotes for null alleles are viable in mice but not in rabbits and probably not in humans. RNA-sequencing analysis of rabbit embryos showed that very few genes (4-29 genes) were differentially expressed among the three HMGA2/dwarf genotypes, suggesting that dwarfism and inviability in rabbits are caused by modest changes in gene expression. Our results show that HMGA2 is critical for normal expression of IGF2BP2, which encodes an RNA-binding protein. Finally, we report a catalog of regions of elevated genetic differentiation between dwarf and normal-size rabbits, including LCORL-NCAPG, STC2, HOXD cluster, and IGF2BP2 Levels and patterns of genetic diversity at the LCORL-NCAPG locus further suggest that small size in dwarf breeds was enhanced by crosses with wild rabbits. Overall, our results imply that small size in dwarf rabbits results from a large effect, loss-of-function (LOF) mutation in HMGA2 combined with polygenic selection.


Assuntos
Nanismo/genética , Deleção de Genes , Proteína HMGA2/genética , Coelhos/genética , Animais , Éxons , Proteína HMGA2/metabolismo , Regiões Promotoras Genéticas , Proteínas de Ligação a RNA/genética , Proteínas de Ligação a RNA/metabolismo , Coelhos/crescimento & desenvolvimento
8.
Stem Cells Int ; 2016: 1492694, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26839553

RESUMO

Transforming growth factor-beta 1 (TGF-ß1) plays a central role in hepatic progenitor cells- (HPCs-) mediated liver repair and fibrosis. However, different effects of TGF-ß1 on progenitor cells have not been described. In this study, both in vitro (HPCs cocultured with hepatic stellate cells (HSCs) in transwells) and in vivo (CCl4-injured liver fibrosis rat) systems were used to evaluate the impacts. We found that HPCs pretreated with TGF-ß1 for 12 hours inhibited the activation of HSCs, while sensitization for 48 hours increased the activation of HSCs. Consistent with these in vitro results, the in vivo fibrosis rat model showed the same time-dependent dual effect of TGF-ß1. Regression of liver fibrosis as well as normalization of serum aminotransferase and albumin levels was detected in the rats transplanted with HPCs pretreated with TGF-ß1 for 12 hours. In contrast, severe liver fibrosis and elevated collagen-1 levels were detected in the rats transplanted with HPCs pretreated with TGF-ß1 for 48 hours. Furthermore, the TGF-ß1-pretreated HPCs were shown to deactivate HSCs via enhancing SERPINE1 expression. Inhibition of SERPINE1 reversed the deactivation response in a dose-dependent manner.

9.
Chongqing Medicine ; (36): 2917-2919, 2016.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-497244

RESUMO

Objective To analyze the change of chromosome test level after participating in the inter‐laboratory proficiency test(PT) program of the College of American Pathologists (CAP) .Methods The results for participating in CAP PT during 2011-2014 were analyzed ,the accuracy of the cytogenetic chromosome quality control test in this laboratory was obtained accord‐ing to the CAP evaluation results ,and the effect of CAP external quality assessment item on increasing the chromosome detection level in this laboratory was evaluated by analyzing the chromosome band levels before and after participating in CAP .Results This laboratory participated in CAP PT test for 10 times during 2011-2014 ,a total of 59 cases were analyzed ,the accuracy rate for jud‐ging chromosome karyotype was 100% ,the karyotype description accuracy rate was 95 .1% .The chromosome test results of clinical cases in this laboratory displayed that peripheral blood chromosome abnormal detection rate was 18 .9% and bone marrow chromo‐some abnormal detection rate was 25 .9% ,the abnormal rate of newly diagnosed leukemia was 66 .8% ;the detection failure rates of peripheral blood chromosome and bone marrow chromosome were 0 .5% and 5 .0% respectively ;the detection failure rates of pe‐ripheral blood chromosome and bone marrow chromosome after participating in CAP were decreased ,the chromosome band average level was improved ,showing statistical difference compared with those before participating in CAP (P<0 .01) .Conclusion Partici‐pating in high quality external laboratory assessment item can increase the clinical analytic level of cytogenetic chromosome test .

10.
Histol Histopathol ; 30(2): 205-12, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25108174

RESUMO

AIM: Angiogenesis is considered an important pathophysiological feature of portal hypertension. We investigated the ability of angiogenesis, as CD34-positive microvessel density (MVD), to differentiate portal pressure in a CCl4-induced rat cirrhosis model. METHODS: Cirrhosis was induced by intraperitoneal injection of carbon tetrachloride in 46 male adult Sprague-Dawley rats. A catheter connected to a highly sensitive pressure transducer was inserted into the portal vein to continuously record portal pressure. Fibrosis area, nodule size and MVD were assessed by image morphometry. RESULTS: Of 42 rats in which portal pressure was measured successfully, 27 (64%) had portal pressure ≥10 mmHg, defined as significant portal hypertension. MVD was 4.5-fold higher and fibrosis area 13.0-fold higher in rats with significant portal hypertension than in rats with portal pressure <10 mmHg. Portal pressure was significantly correlated with MVD (r=0.491, p<0.001) and fibrosis area (r=0.545, p<0.001) in all animals, but only MVD correlated with portal pressure (r=0.731 p<0.001) in rats with significant portal hypertension. The area under receiver operating characteristic curve for MVD in all rats was 0.953 (95% CI: 0.875-1.031) and optimum cutoff for MVD was 18/mm², with 96.3% sensitivity and 93.3% specificity. CONCLUSIONS: We found that MVD, measured by CD34 immunostaining, was better able than the fibrosis area to discriminate significant portal hypertension in rats, suggesting that MVD could be a surrogate marker for portal hypertension in patients with liver diseases.


Assuntos
Hipertensão Portal/diagnóstico , Neovascularização Patológica/patologia , Animais , Antígenos CD34/genética , Antígenos CD34/metabolismo , Biomarcadores , Pressão Sanguínea , Capilares/patologia , Diagnóstico Diferencial , Hipertensão Portal/metabolismo , Hipertensão Portal/patologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Neovascularização Patológica/genética , Ratos , Ratos Sprague-Dawley
11.
Yi Chuan ; 36(10): 995-1005, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25406247

RESUMO

A genome-wide scan for pig umbilical hernia (UH) was performed in a White Duroc × Erhualian resource population reported by our previously study, which detected two susceptibility microsatellite markers (SWR1928 on SSC7 and SW830 on SSC10) significantly affecting pig UH. Herein, fine mapping studies and identification of susceptibility genes for UH were performed in two different populations. A total of 40 SNPs in 12 positional candidate genes located on the two significant segments were genotyped in the F2/F3 resource population. Quality control of the genotype data and transmission disequilibrium test (TDT) were conducted using Plink v1.07 software. The results showed that g.708G>A in IL16 (interleukin 16) gene and g.10664G>A in CDC73 (cell division cycle 73) gene were significantly associated with pig UH. These two prominent SNPs and another two weakly associated SNPs g.10546A>G and g.10811A>G in CDC73 were also undergone the replication TDT test in the outbred commercial populations. All SNPs in the CDC73 gene were confirmed to be significantly associated with pig UH (P<0.05), including g. 10546A>G and g.10811A>G with extreme significant level (P<0.01). Based on these results, CDC73 should be a susceptibility gene for pig UH according to its biological functions and the molecular pathogenesis of UH.


Assuntos
Mapeamento Cromossômico , Predisposição Genética para Doença/genética , Hérnia Umbilical/veterinária , Desequilíbrio de Ligação , Doenças dos Suínos/genética , Suínos/genética , Animais , Cruzamento , Técnicas de Genotipagem , Hérnia Umbilical/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único
12.
PLoS One ; 9(2): e87957, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24504507

RESUMO

BACKGROUND/AIM: Diffraction enhanced imaging (DEI) is a synchrotron radiation X-ray phase-contrast imaging technique that can better reveal the microstructure of biological soft tissues than conventional X-rays. The aim of this study is to investigate the angio-architectural changes of the liver during fibrosis, cirrhosis and its subsequent regression by applying synchrotron radiation based DEI. METHODS: DEI experiments were performed at the 4W1A station of Beijing Synchrotron Radiation Facility. Twenty-four Sprague-Dawley rats were induced with liver fibrosis by carbon tetrachloride (CCl4) for up to 10 weeks, after which spontaneous regression started and continued until week 30. Quantitative analysis of the DEI images yielded the mean vascular density and intercapillary distance, which was then re-confirmed by immunohistochemical analysis of CD34. RESULTS: Based on the DEI results, the mean vascular density was 1.4-fold higher in fibrotic rats (at week 6) and 2-fold higher in cirrhotic rats (at week 10) compared with the control (p<0.05). Accordingly, the intercapillary distance decreased to 563.89 ± 243.35 µm in fibrotic rats and 392.90 ± 92.68 µm in cirrhotic rats compared with 673.85 ± 214.16 µm in the control (p<0.05). During fibrosis regression at week 30, vascular density was 0.7-fold lower and intercapillary distance increased to 548.60 ± 210.94 µm as compared with cirrhotic rats (p<0.05).In parallel to the DEI results, immunohistochemical analysis of CD34 showed similar changes. CONCLUSION: Synchrotron-based DEI can conduct radiological as well as pathological analysis. Our results are consistent with previous reports indicating that angiogenesis is directly proportional to fibrosis progression. Furthermore, by clarifying the vascular characteristics of liver diseases, DEI reveals that cirrhosis cannot fully reverse during fibrosis regression.


Assuntos
Diagnóstico por Imagem , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/patologia , Microvasos/patologia , Neovascularização Patológica/diagnóstico por imagem , Intensificação de Imagem Radiográfica , Animais , Antígenos CD34/metabolismo , Diagnóstico por Imagem/métodos , Modelos Animais de Doenças , Progressão da Doença , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Cirrose Hepática/induzido quimicamente , Cirrose Hepática/metabolismo , Masculino , Microvasos/metabolismo , Neovascularização Patológica/metabolismo , Intensificação de Imagem Radiográfica/métodos , Ratos
14.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-639114

RESUMO

Objective To compare the humoral immunity features of acute glomerulonephritis and nephritic syndrome(NS) in children for earlier differential diagnosis and rational administration.Methods Nephelometry was used to determinate the serum level of immunoglobulin(Ig)G,IgA,IgM,C3,C4 in children by England MININEPH machine and correlated reagent. The serum level of IgE was determined by IgE enzyme linked immunosorbent assay(ELISA),assay ELISA kit of America E&ELABSINC company. Immunoturbidimetry and westergren method were used to detect anti-streptolysin O(ASO) and erythrocyte sedimentation rate(ESR),respectively.Results There were significant diffe-rence features of humoral immunity between acute glomerulonephritis and NS in children.IgG,IgA,IgE,C3,C4 had significant difference between acute glomerulonephritis children and healthy children(Pa

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