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991.
Fecal microbiota transplant (FMT) is recommended for Clostridium difficile infection (CDI) treatment; however, use in solid organ transplantation (SOT) patients has theoretical safety concerns. This multicenter, retrospective study evaluated FMT safety, effectiveness, and risk factors for failure in SOT patients. Primary cure and overall cure were defined as resolution of diarrhea or negative C difficile stool test after a single FMT or after subsequent FMT(s) ± anti‐CDI antibiotics, respectively. Ninety‐four SOT patients underwent FMT, 78% for recurrent CDI and 22% for severe or fulminant CDI. FMT‐related adverse events (AE) occurred in 22.3% of cases, mainly comprising self‐limiting conditions including nausea, abdominal pain, and FMT‐related diarrhea. Severe AEs occurred in 3.2% of cases, with no FMT‐related bacteremia. After FMT, 25% of patients with underlying inflammatory bowel disease had worsening disease activity, while 14% of cytomegalovirus‐seropositive patients had reactivation. At 3 months, primary cure was 58.7%, while overall cure was 91.3%. Predictors of failing a single FMT included inpatient status, severe and fulminant CDI, presence of pseudomembranous colitis, and use of non‐CDI antibiotics at the time of FMT. These data suggest FMT is safe in SOT patients. However, repeated FMT(s) or additional antibiotics may be needed to optimize rates of cure with FMT.  相似文献   
992.
Standardized donor‐derived cell‐free DNA (dd‐cfDNA) testing has been introduced into clinical use to monitor kidney transplant recipients for rejection. This report describes the performance of this dd‐cfDNA assay to detect allograft rejection in samples from heart transplant (HT) recipients undergoing surveillance monitoring across the United States. Venous blood was longitudinally sampled from 740 HT recipients from 26 centers and in a single‐center cohort of 33 patients at high risk for antibody‐mediated rejection (AMR). Plasma dd‐cfDNA was quantified by using targeted amplification and sequencing of a single nucleotide polymorphism panel. The dd‐cfDNA levels were correlated to paired events of biopsy‐based diagnosis of rejection. The median dd‐cfDNA was 0.07% in reference HT recipients (2164 samples) and 0.17% in samples classified as acute rejection (35 samples; P = .005). At a 0.2% threshold, dd‐cfDNA had a 44% sensitivity to detect rejection and a 97% negative predictive value. In the cohort at risk for AMR (11 samples), dd‐cfDNA levels were elevated 3‐fold in AMR compared with patients without AMR (99 samples, P = .004). The standardized dd‐cfDNA test identified acute rejection in samples from a broad population of HT recipients. The reported test performance characteristics will guide the next stage of clinical utility studies of the dd‐cfDNA assay.  相似文献   
993.
Objectives We aimed to examine whether the C-reactive protein (CRP) level could be used to differentiate between major depressive disorder (MDD) and bipolar II disorder (BD II). Methods Ninety-six healthy controls, 88 BD II and 72 MDD drug-naïve patients in their major depressive episodes were enrolled. The fasting plasma level of high-sensitivity CRP was assessed at baseline and after treatment. Results The BD II patients presented significantly higher 17-item Hamilton Depression Rating Scale (HDRS) scores and CRP levels at baseline when adjustment for age, gender, and body mass index (P?< 0.001 and P?< 0.001, respectively). After treatment the CRP levels remained significantly different (P?< 0.001), although the HDRS score was not significantly different between the BD II and MDD patients. A receiver-operating characteristic analysis showed that a baseline CRP level of 621.6?ng/mL could discriminate between BD II and MDD, with an area under the curve of 0.816 and a sensitivity and specificity of 0.699 and 0.882, respectively. Furthermore, the baseline CRP level greater than 621.6?ng/ml had 28.2 higher odds of a diagnosis of BD II (P?< 0.001, 95% confidence interval: 10.96–72.35). Conclusions The level of CRP plays a role of biomarker to differentiate between MDD and BD II depression in both their depressed and euthymic state.  相似文献   
994.

Background

Primary headaches include migraines, tension-type headaches and other primary headache syndromes. Migraines and tension-type headaches are associated with patient discomfort and other diseases. This study aimed to investigate the association between primary headaches and the risk of developing dementia, and to clarify the association between different types of headaches and dementia.

Materials and Methods

We conducted a nationwide matched cohort population-based study. A total of 3,620 patients with newly diagnosed primary headaches, including migraines and tension-type headaches, between January 1 and December 31, 2000 were selected from the National Health Insurance Research Database of Taiwan, along with 10,860 controls matched for sex and age. After adjusting for confounding factors, Fine and Gray?s competing risk analysis was used to compare the risk of developing dementia during 10 years of follow-up.

Results

Of the study subjects, 170 (4.70 %) developed dementia compared with 433 (3.99%) of the controls. Fine and Gray?s competing risk analysis revealed that the study subjects were more likely to develop dementia (hazard ratio = 2.057; 95% CI: 1.718-2.462; P < 0.001). After adjusting for sex, age, monthly income, urbanization level, geographic region of residence and comorbidities, the hazard ratio for dementia was 2.048 (95% CI: 1.705-2.461, P < 0.001). Migraines and tension-type headaches were associated with nonvascular dementia but not vascular dementia.

Conclusions

The patients with headaches had a 105% increased risk of dementia. Further studies are needed to elucidate the underlying mechanisms.  相似文献   
995.
996.
The purpose of the study was to examine the physicochemical properties of mineral trioxide aggregate (MTA)-like cements prepared from SiO2, CaO, and Al2O3 as matrices, and ZnO, MgO, and Fe2O3 as additives. The MTA-like cements showed a significantly (p < 0.05) faster setting time (<14 minutes) than MTA when mixed with water, although there was a significant decrease (p < 0.05) in diametral tensile strength, ranging from 0.9 to 3.1 MPa in comparison to MTA (4.4 MPa). The addition of ZnO, MgO, and Fe2O3 to the MTA-like cement led to a significantly (p < 0.05) higher strength than MTA-like cement without additives. The pH values of the MTA-like cements were changed from an initial 11 to a high of 13, similar to the results of MTA. Future characterization of the examined MTA-like cement with shortened setting time is needed before it is considered a viable candidate for dental root-end–filling applications.  相似文献   
997.
The emergence and ensuing dominance of COVID-19 on the world stage has emphasized the urgency of efficient animal models for the development of therapeutics for and assessment of immune responses to SARS-CoV-2 infection. Shortcomings of current animal models for SARS-CoV-2 include limited lower respiratory disease, divergence from clinical COVID-19 disease, and requirements for host genetic modifications to permit infection. In this study, n = 12 specific-pathogen-free domestic cats were infected intratracheally with SARS-CoV-2 to evaluate clinical disease, histopathologic lesions, and viral infection kinetics at 4 and 8 days post-inoculation; n = 6 sham-inoculated cats served as controls. Intratracheal inoculation of SARS-CoV-2 produced a significant degree of clinical disease (lethargy, fever, dyspnea, and dry cough) consistent with that observed in the early exudative phase of COVID-19. Pulmonary lesions such as diffuse alveolar damage, hyaline membrane formation, fibrin deposition, and proteinaceous exudates were also observed with SARS-CoV-2 infection, replicating lesions identified in people hospitalized with ARDS from COVID-19. A significant correlation was observed between the degree of clinical disease identified in infected cats and pulmonary lesions. Viral loads and ACE2 expression were also quantified in nasal turbinates, distal trachea, lungs, and other organs. Results of this study validate a feline model for SARS-CoV-2 infection that results in clinical disease and histopathologic lesions consistent with acute COVID-19 in humans, thus encouraging its use for future translational studies.  相似文献   
998.
三价铬和六价铬小鼠急性毒性及致突变性研究   总被引:1,自引:0,他引:1  
目的比较不同价态铬化合物急性毒性及致突变毒性。方法采用鼠伤寒沙门菌/微粒体试验(Ames)实验、小鼠急性毒性实验和小鼠骨髓微核实验检测铬化合物的急性毒性和致突变毒性。结果K2Cr2O2的LD50明显高于CrCl3;Ames试验CrCl3呈阴性结果,K2Cr2O7呈阳性结果。小鼠骨髓微核实验CrCl3呈阴性结果;K2Cr2O7各剂量组微核率明显高于对照组(P〈0.05)。CrCl3和K2Cr2O1各剂量组骨髓细胞PCE/RBC比值随剂量的增高均呈现下降趋势,但均高于0.1。结论本实验表明CrCl3不具有致突变作用,K2Cr2O3不但急性毒性明显高于CrCl3,而且具有致突变作用。  相似文献   
999.
Gemcitabine (2′-deoxy-2′, 2′-difluorocytidine; Gem) is a nucleoside anti-metabolite and is commonly used for treating various human cancers including human bladder carcinoma. Gemcitabine not only functions as a suicide nucleoside analog but also inhibits DNA polymerase activity and results in the termination of chain elongation. Using 2-dimensional gel electrophoresis analysis, a Gem-induced protein was identified as UBE2M (a.k.a. UBC12), a NEDD8 conjugation E2 enzyme which contributes to protein degradation. Gem induced UBE2M expression at both RNA and protein levels in several human cancer cell lines. The induction of UBE2M by Gem was accompanied by a reduction in p27Kip1 protein levels, which could be restored by silencing UBE2M expression with siRNA or by treating cells with the proteasome inhibitor MG132, indicating that UBE2M mediates Gem-induced p27Kip1 protein degradation. The induction of UBE2M and reduction of p27Kip1 by Gem were prevented by the PI3K inhibitor LY294002. These results indicate that PI3K activity is necessary for Gem-induced UBE2M expression and that UBE2M facilitates degradation of p27Kip1. Notably, silencing of UBE2M expression reduced Gem sensitivity in NTUB1 cells, suggesting that UBE2M mediates in part cell sensitivity to Gem, possibly by degradation of p27Kip1. Analysis of Gem-resistant sub lines also showed that loss of UBE2M and increased p27Kip1 expression were associated with the acquisition of drug resistance. In conclusion, our results demonstrate a role for UBE2M in mediating cytotoxicity of gemcitabine in human urothelial carcinoma cells while also suggesting a potential function of p27Kip1 in drug resistance.  相似文献   
1000.
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