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The effect of carbon nanotubes (CNTs) on the aging behavior of Mg-9Al matrix composites was studied, and the evolution of microstructures, mechanical properties and thermal conductivity of composites during the aging treatment were discussed. Results show that the addition of CNTs increases the solid solubility of Al in Mg matrix and limited the migration of grain boundaries during the aging process, which can promote the formation of continuous precipitated phases β-Mg17Al12 in CNTs/Mg-9Al composites. The rod-shaped continuous precipitates in coherent relationship with Mg matrix can effectively hinder the dislocation movement, which can improve the mechanical properties of the composites. Besides, the reduction of solid solution Al atoms during aging process and the addition of CNTs can improve the thermal conductivity of the composites. The property evaluation indicates that the tensile yield strength, ultimate tensile strength, diffusivity and thermal conductivity of peak-aged 0.4CNTs/Mg-9Al composite are 275 MPa, 369 MPa, 34.5 mm2/s and 68.4 W/(m·K) respectively, showing 17%, 23%, 43% and 45% increasing in comparison with those of Mg-9Al before aging.

BackgroundThe patient with ulcerative colitis (UC) in remission has a long course of disease, and needs a long-term maintenance treatment. Traditional Chinese medicine (TCM) has proved to be partially effective in treating UC in remission, but the efficacy of Jianpiqingrehuashi granular decoction (JPQRHSGD) against UC in remission is not yet clear.ObjectiveTo evaluate the efficacy and safety of JPQRHSGD with mesalamine versus mesalamine in the treatment of UC in remission using an N-of-1 trial.MethodsAn N-of-1 trial was conducted between June 2020 and March 2021. Participant was an outpatient with UC in remission with spleen deficiency-induced dampness-heat syndrome who was selected from the First Affiliated Hospital, Guangzhou University of Chinese Medicine. The patient received a treatment program, namely four rounds of treatment without washout consisting of eight cycles〔each round includes two cycles, that was, one-month intervention treatment (use of JPQRHSGD with mesalamine) alternating with one-month control treatment (taking mesalamine only) 〕. Efficaciesof two types of treatment were evaluated by of the TCM Syndrome Score (TCMSS) , Bristol Stool Form Scale (BSFS) , visual analogue scale (VAS) for abdominal pain and diarrhea, and Short Health Scale (SHS) . Safety was also compared between the two treatments.ResultsThe total TCMSS in intervention period was significantly lower than that in control period (P

BackgroundIn patients with peptic ulcer bleeding (PUB) , intragastric blood and unavoidable medicine, including acid suppressive agent are suspected as limitary factors to diagnose Helicobacter pylori (H.pylori) infection correctly. The research conclusions about the accuracy of urease breath test (UBT) and stool antigen test (SAT) in patients with PUB are inconsistent.ObjectiveTo clarify the accuracy of UBT and SAT for H.pylori infection in PUB patients.MethodsPubMed, EMBase, the Cochrane Library, Web of Science, CNKI, Wanfang Data Knowledge Service Platform, China Biomedical Literature Database (CBM) were retrieved by computer for relevant articles related to the diagnosis of H.pylori infection by UBT and/or SAT published from the establishment of the database to March 31, 2021. The QUADAS-2 tool was used to evaluate the quality of the extracted literature. The bivariate mixed-effects regression model and network meta-analysis model (NMA) were used to synthesize diagnostic test data. Meta-regression and subgroup analysis were performed to explore the sources of heterogeneity.ResultsA total of 18 articles were included, with a total of 25 studies and 1 105 patients. Meta-analysis results showed that the combined sensitivity of UBT and SAT for diagnosing H.pylori infection in PUB patients were 0.90〔95%CI (0.79, 0.95) 〕 and 0.89〔95%CI (0.81, 0.94) 〕, the combined specificity were 0.91〔95%CI (0.86, 0.95) 〕 and 0.75〔95%CI (0.59, 0.87) 〕, the combined diagnostic odds ratio were 88.89〔95%CI (31.01, 254.82) 〕 and 24.35〔95%CI (13.76, 43.09) 〕, the combined positive likelihood ratio were 10.07〔95%CI (6.07, 16.71) 〕 and 3.60〔95%CI (2.11, 6.12) 〕, the combined negative likelihood ratio were 0.11〔95%CI (0.05, 0.24) 〕 and 0.15〔95%CI (0.09, 0.24) 〕, the area under the SROC curve were 0.93〔95%CI (0.90, 0.95) 〕 and 0.91〔95%CI (0.88, 0.93) 〕. Meta regression showed that the sampling time had an impact on the sensitivity heterogeneity of UBT and SAT, and the sampling time and the H.pylori infection criterion had an impact on the combined specificity heterogeneity of UBT. The Deek funnel chart indicated that there was no potential publication bias among the included researches (PUBT=0.53, PSAT=0.64) .ConclusionIn patients with PUB, UBT had a promising performance for the diagnosis of H.pylori infection. Because of the high number of false-positive results, SAT was not recommended for use in patients with PUB alone. At the same time, in order to avoid the impact of PPI on the detection results, it was recommended to perform the diagnostic tests as soon as possible under the condition of stable hemodynamics.

Objective: While it's widely accepted that the etiology of ulcerative colitis (UC) involves both genetic and environmental factors, the pathogenesis of ulcerative colitis is still poorly understood. Intestinal epithelial apoptosis is one of the most common histopathological changes of UC and the expression of a number of apoptosis genes may contribute to the progression of UC. MicroRNAs have recently emerged as powerful regulators of diverse cellular processes and have been shown to be involved in many immune-mediated disorders such as psoriasis, rheumatoid arthritis, lupus, and asthma. A unique microRNA expression profile has been identified in UC, suggesting that, microRNAs play an important role in the pathogenesis of UC. We investigated the role of miR-29a in intestinal epithelial apoptosis in UC., Methods: The expression of miR-29a and Mcl-1, an anti-apoptotic BCL-2 family member, was evaluated in both UC patients and UC mice model induced by dextran sodium sulfate (DSS). The apoptosis rate of intestinal epithelial cells was also evaluated., Results: In UC patients and DSS-induced UC in mice, the expression of miR-29a and Mcl-1, were up-regulated and down-regulated, respectively. We identified a miR-29a binding site (7 nucleotides) on the 3'UTR of mcl-1 and mutation in this binding site on the 3'UTR of mcl-1 led to mis-match between miR-29a and mcl-1. Knockout of Mcl-1 caused apoptosis of the colonic epithelial HT29 cells. In addition, miR-29a regulated intestinal epithelial apoptosis by down-regulating the expression of Mcl-1., Conclusion: miR-29a is involved in the pathogenesis of UC by regulating intestinal epithelial apoptosis via Mcl-1.