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41.
Despite that clinical trials have been examining the safety profile of coronavirus disease 2019 (COVID-19) vaccines, there are concerns about long-term side effects as the number of vaccinations increases. Herein, we report a case of new-onset renal-limited anti-myeloperoxidase (MPO) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis after booster vaccination with the mRNA 1273 (Moderna) vaccine. A 72-year-old woman with no specific past history, and who had a normal renal function, developed ANCA-associated vasculitis following heterologous booster with mRNA1273 (Moderna) vaccine. After a kidney biopsy, she was diagnosed with ANCA-associated pauci-immune crescentic glomerulonephritis. Her renal function and constitutional symptoms have been improved with treatment with plasmapheresis, intravenous cyclophosphamide and steroid pulse therapy (intravenous 500 mg of methylprednisolone sodium succinate for 3 days) followed by a reduced steroid regimen.  相似文献   
42.
Bronchiolitis generally refers to inflammation and/or fibrosis of the non-cartilaginous small airways located approximately from the 8th airway generation down to the terminal and respiratory bronchioles. In contrast to young children, the frequency of small airway infection in adult bronchiolitis appears less frequent and a number of other pathophysiological conditions have been implicated in adult bronchiolitis. However, little information is available on the exact medical burden of bronchiolitis such as its prevalence and comorbidities in the adult population. The aim of this study is to elucidate the prevalence and comorbidities of bronchiolitis. We used the Korea National Health Insurance Service-National Sample Cohort, which provides data for 1,000,000 individuals out of the entire population by 2% stratified random sampling according to age, sex, residential area, and level of household income. We defined the cause of bronchiolitis other than acute infection as a patient with diagnostic code J448 or J684 and over 20 years of age who visited a clinic or hospital in South Korea. Then, 1:1 propensity score matching was performed to define a non-bronchiolitis (control) group to compare the comorbidities and mortality in the 2 groups. The overall prevalence of bronchiolitis was 688 cases/1,000,000 population during the study period (95% confidence interval, 625–751). The most common comorbid clinical condition in adults with bronchiolitis was rhinitis (52.3%), followed by bronchial asthma (52.23%), hypertension (43.69%), gastroesophageal reflux disease (30.56%), sinusitis (28.72%), diabetes (22.77%), and osteoporosis (17.85%). Other common bronchiolitis-associated comorbidities were cerebrovascular disease (16.86%), angina (14.37%), peripheral vascular disease (13.42%), congestive heart failure (11.9%), and malignancy in any organ (10.6%). Healthcare costs for bronchiolitis increased steeply during the same period. Malignancy in any organ was the leading cause of mortality in the patient group, followed by bronchiolitis itself. Further larger prospective multiethnic cohort studies should be carried out in the near future.  相似文献   
43.
BackgroundThe rapid urease test (RUT) is a major diagnostic tool for detecting Helicobacter pylori infection. This study aimed to establish an objective method for measuring the color changes in the RUT kit to improve the test’s diagnostic accuracy.MethodsA UV-visible spectrophotometer was selected as the colorimeter; experiments were conducted in three stages to objectively identify the color changes in the RUT kit.ResultsFirst, the urea broth solution showed an identifiable color change from yellow to red as the pH increased by 0.2. The largest transmittance difference detected using the UV-visible spectrophotometer was observed at a 590-nm wavelength. Second, the commercialized RUT kit also showed a gradual color change according to the pH change detected using the UV-visible spectrophotometer. Third, 13 cases of negative RUT results with a biopsy specimen and 16 of positive RUT results were collected. The transmittance detected using the UV-visible spectrophotometer showed a clear division between the positive and negative RUT groups; the largest difference was observed at a 559-nm wavelength. The lowest transmittance in the negative RUT group was 64, while the highest in the positive RUT group was 56, at the 559-nm wavelength. The UV-visible spectrophotometry reading showed a consistency of 92.7% compared with that of manual reading.ConclusionA transmittance of 60 at a 559-nm wavelength detected using UV-visible spectrophotometer can be used as a cutoff value for interpreting RUT results; this will help develop an automatic RUT kit reader with a high accuracy.  相似文献   
44.
Background:Kawasaki disease (KD) is a major cause of coronary artery lesions (CALs) in children. Approximately 10% to 20% of children treated with intravenous immunoglobulin are intravenous immunoglobulin-resistant. This study evaluated the efficacy and safety of adding herbal medicine to conventional western medicines versus conventional western medicines alone for CALs in children with KD.Methods:This study searched 9 electronic databases until August 31, 2021. The inclusion criteria were the randomized controlled trials (RCTs) that assessed the CALs in children with KD and compared integrative treatment with conventional western treatments. Two authors searched independently for RCTs, including eligible articles that fulfilled the inclusion criteria, extracted data, and assessed the methodological quality using the Cochrane risk of bias tool. Meta-analysis was conducted using Cochrane Collaboration''s Review Manager 5.4 software. The effect size was presented as the risk ratio (RR), and the fixed-effect models were used to pool the results.Results:The finally selected 12 studies included a total of 1030 KD patients. According to a meta-analysis, the integrative treatment showed better results than the conventional treatment in the CAL prevalence rate (RR = 2.00; 95% confidence interval [CI], 1.49–2.71; P < .00001), CAL recovery rate (RR = 1.27; 95% CI, 1.05–1.54; P = .02), and total effective rate (RR = 1.17; 95% CI, 1.11–1.23; P < .00001). Only 2 studies referred to the safety of the treatment. The asymmetrical funnel plot of the CAL prevalence rate indicated the possibility of potential publication bias.Conclusions:This review found the integrative treatment to be more effective in reducing the CAL prevalence rate and increasing the CAL recovery rate and total effective rate in KD patients than conventional western treatment. However, additional well-designed RCTs will be needed further to compensate restrictions of insufficient trials on safety, methodological quality, and publication bias.  相似文献   
45.
Sarcopenia refers to a decline in muscle mass and strength with age, causing significant impairment in the ability to carry out normal daily functions and increased risk of falls and fractures, eventually leading to loss of independence. Maintaining protein homeostasis is an important factor in preventing muscle loss, and the decrease in muscle mass is caused by an imbalance between anabolism and catabolism of muscle proteins. Although β-sitosterol has various effects such as anti-inflammatory, protective effect against nonalcoholic fatty liver disease (NAFLD), antioxidant, and antidiabetic activity, the mechanism of β-sitosterol effect on the catabolic pathway was not well known. β-sitosterol was assessed in vitro and in vivo using a dexamethasone-induced muscle atrophy mice model and C2C12 myoblasts. β-sitosterol protected mice from dexamethasone-induced muscle mass loss. The thickness of gastrocnemius muscle myofibers was increased in dexamethasone with the β-sitosterol treatment group (DS). Grip strength and creatine kinase (CK) activity were also recovered when β-sitosterol was treated. The muscle loss inhibitory efficacy of β-sitosterol in dexamethasone-induced muscle atrophy in C2C12 myotube was also verified in C2C12 myoblast. β-sitosterol also recovered the width of myotubes. The protein expression of muscle atrophy F-box (MAFbx) was increased in dexamethasone-treated animal models and C2C12 myoblast, but it was reduced when β-sitosterol was treated. MuRF1 also showed similar results to MAFbx in the mRNA level of C2C12 myotubes. In addition, in the gastrocnemius and tibialis anterior muscles of mouse models, Forkhead Box O1 (FoxO1) protein was increased in the dexamethasone-treated group (Dexa) compared with the control group and reduced in the DS group. Therefore, β-sitosterol would be a potential treatment agent for aging sarcopenia.  相似文献   
46.
Mosapride and cisapride are gastroprokinetic agents with 5-hydroxytryptamine4 receptor agonist activity and have been widely used in the treatment of a variety of gastrointestinal disorders. The effects of mosapride and cisapride on cloned Kv4.3 channels stably expressed in Chinese hamster ovary cells were investigated using the whole-cell patch-clamp technique. Mosapride and cisapride inhibited Kv4.3 in a concentration-dependent manner with IC50 values of 15.2 and 9.8 μM, respectively. Mosapride accelerated the rate of inactivation and activation of Kv4.3 in a concentration-dependent manner and thereby decreased the time to peak. The rate constants of association (k +1) and dissociation (k ?1) for mosapride were 9.9 μM?1 s?1 and 151.3 s?1, respectively. The K D (k ?1/k +1) was 16.2 μM, similar to the IC50 value calculated from the concentration–response curve. Voltage-dependent inhibition by mosapride was observed in the voltage range for channel opening but was not observed over a voltage range in which all Kv4.3 channels were open. Both the steady-state activation and inactivation curves of Kv4.3 were shifted in the hyperpolarizing direction in the presence of mosapride. Mosapride also caused a substantial acceleration in closed-state inactivation of Kv4.3. Mosapride produced use-dependent inhibition, which was consistent with a slow recovery from inactivation of Kv4.3. M1 and norcisapride, the major metabolites of mosapride and cisapride, respectively, had little or no effect on Kv4.3. These results indicate that mosapride inhibits Kv4.3 by both preferential binding to the open state of the channels during depolarization and acceleration of the closed-state inactivation at subthreshold potentials.  相似文献   
47.
This study aimed to describe the distribution of water-arsenic (As) valence states and its relationship to areas with endemic arsenism in the Datong basin. Drinking water samples of patients with endemic arsenism and a control group were examined using hydride generation atomic fluorescence spectrometry (HG-AFS). We analyzed the data using SPSS10.0 for Windows. The As(III)/As ratio was 52.1% in the water sample, exceeding the national standard of 0.05 mg/L. The As(III)/As ratio significantly varied among the different stages in the disease-state groups, and with the control group (χ 2 = 22.4, P<0.01). The As(III)/As(V) ratio significantly varied in the four groups (χ 2 = 26.19, P<0.01), with a tendency to increase along with the seriousness of the disease state. The most common type of drinking water arsenic valence state was As(III) in the endemic disease-areas. Endemic arsenism was positively correlated with As(III). This led us to conclude that the fraction of each water-arsenic valence state should be studied when determining the arsenic content of drinking water. Translated from Chinese Journal of Endemiology, 2006, 25(1): 64–66 [译自: 中国地方病学杂志]  相似文献   
48.
目的 观察贴壁法分离提取大鼠乳鼠骨髓间充质干细胞(mesenchymal stem cells,MSCs)并进行体外扩增培养的可行性并探讨其生物学特性,为进一步实验研究作基础.方法 实验2008-01/06于南昌大学第一附属医院泌尿外科研究所完成.贴壁法分离培养SD大鼠乳鼠MSCs,经CD29、CD34、CD44、CD45鉴定MSCs,并绘制不同代数细胞生长曲线和贴壁率曲线分析其生物学特性.结果 ①原代细胞生长潜伏期略长,孵育24 h后小部分圆形单核细胞开始贴壁,48 h可见巢状克隆集落形成,贴壁细胞呈多形性,贴壁3d后增殖加快,9d后基本融合.②生长曲线及贴壁率曲线提示第2至第6代细胞接种存活率基本相同,生长曲线基本一致,而第7代以后细胞的生长速度渐缓,贴壁时间延长,细胞接种存活率也明显降低,并出现衰化现象.③免疫组化鉴定结果 显示CD29、CD44表达基本阳性,而CD34、CD45表达阴性.结论 贴壁法比较容易分离培养MSCs,为组织工程的应用提供了足够的种子来源,MSCs有一定的增殖能力但并不是无限的,而是随传代扩增逐渐衰化,因此了解和掌握MSCs的生物学特性为进一步研究应用打下基础.  相似文献   
49.
50.
Vanadium dioxide (VO2) is one of the extensively studied strongly correlated oxides due to its intriguing insulator–metal transition near room temperature. In this work, we investigated temperature-dependent nanoscale conduction in an epitaxial VO2 film grown on an Al2O3 substrate using conductive-atomic force microscopy (C-AFM). We observed that only the regions near the grain boundaries are conductive, producing intriguing donut patterns in C-AFM images. Such donut patterns were observed in the entire measured temperature range (300–355 K). The current values near the grain boundaries increased by approximately two orders of magnitude with an increase in the temperature, which is consistent with the macroscopic transport data. The spatially-varied conduction behavior is ascribed to the coexistence of different monoclinic phases, i.e., M1 and M2 phases, based on the results of temperature-dependent Raman spectroscopy. Furthermore, we investigated the conduction mechanism in the relatively conductive M1 phase regions at room temperature using current–voltage (IV) spectroscopy and deep data analysis. Bayesian linear unmixing and k-means clustering showed three distinct types of conduction behavior, which classical C-AFM cannot resolve. We found that the conduction in the M1 phase regions can be explained by the Poole–Frenkel mechanism. This work provides deep insight into IMT behavior in the epitaxial VO2 thin film at the nanoscale, especially the coexistence and evolution of the M1 and M2 phases. This work also highlights that IV spectroscopy combined with deep data analysis is very powerful in investigating local transport in complex oxides and various material systems.

We investigated temperature-dependent nanoscale conduction in an epitaxial VO2 film grown on an Al2O3 substrate using conductive-atomic force microscopy and deep data analysis.  相似文献   
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