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61.
S. Xing X. Zhang J. H. Liu X. Huang P. Zhou 《Clinical and experimental immunology》2019,195(1):121-131
Recent experimental strategies to reduce graft-versus-host disease (GVHD) have focused largely on modifying innate immunity. Toll-like receptor (TLR)-driven myeloid differentiation primary response 88 (MyD88)-dependent signalling pathways that initiate adaptive immune function are also critical for the pathogenesis of GVHD. This study aimed to delineate the role of host MyD88 in the development of acute GVHD following fully major histocompatibility complex-mismatched allogeneic bone marrow transplantation (BMT). When myeloablated BALB/c MyD88 knock-out recipients were transplanted with C57BL/6 (B6) donor cells, they developed significantly more severe GVHD than wild-type (WT) BALB/c hosts. The increased morbidity and mortality in MyD88–/– mice correlated with increased serum levels of lipopolysaccharide and elevated inflammatory cytokines in GVHD target organs. Additionally, MyD88 deficiency in BMT recipients led to increased donor T cell expansion and more donor CD11c+ cell intestinal infiltration with apoptotic cells but reduced proliferation of intestinal epithelial cells compared with that in WT BMT recipients. Decreased expression of tight junction mRNA in epithelial cells of MyD88–/– mice suggested that MyD88 contributes to intestinal integrity. Cox-2 expression in the GVHD-targeted organs of WT mice is increased upon GVHD induction, but this enhanced expression was obviously inhibited by MyD88 deficiency. The present findings demonstrate an unexpected role for host MyD88 in preventing GVHD after allogeneic BMT. 相似文献
62.
A hypothesis for reactivation of pulmonary tuberculosis: How thoracic wall shape affects the epidemiology of tuberculosis
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Aaron R. Casha Liberato Camilleri Alexander Manché Ruben Gatt Daphne Attard Wiktor Wolak Krzysztof Dudek Marilyn Gauci Christopher Giordimaina Joseph N. Grima 《Clinical anatomy (New York, N.Y.)》2015,28(5):614-620
This study was aimed at determining the cause for the high incidence of tuberculosis (TB) reactivation occurring in males with a low body mass index (BMI). Current thinking about pulmonary TB describes infection in the lung apex resulting in cavitation after reactivation. A different hypothesis is put forward for TB infection, suggesting that this occurs in subclinical apical cavities caused by increased pleural stress due to a low BMI body habitus. A finite element analysis (FEA) model of a lung was constructed including indentations for the first rib guided by paramedian sagittal CT reconstructions, and simulations were conducted with varying antero‐posterior (AP) diameters to mimic chests with a different thoracic index (ratio of AP to the transverse chest diameters). A Pubmed search was conducted about gender and thoracic index, and the effects of BMI on TB. FEA modeling revealed a tenfold increase in stress levels at the lung apex in low BMI chests, and a four‐fold increase with a low thoracic index, r2 = 0.9748 P < 0.001. Low thoracic index was related to BMI, P = 0.001. The mean thoracic index was statistically significantly lower in males, P = 0.001, and increased with age in both genders. This article is the first to suggest a possible mechanism linking pulmonary TB reactivation to low BMI due to the flattened thoracic wall shape of young male adults. The low thoracic index in young males may promote TB reactivation due to tissue destruction in the lung apex from high pleural stress levels. Clin. Anat. 28:614–620, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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64.
《Revue d'épidémiologie et de santé publique》2020,68(6):327-336
BackgroundOur study was aimed at examining disparate exposure to physically demanding working conditions in France, a key objective being to identify the types of employees/jobs requiring high-priority preventive actions.MethodsWe analyzed the data from the 2017 French nationwide cross-sectional survey (SUMER) on occupational hazards to which French employees in various sectors were subjected. The prevalence of several types of physically demanding working conditions (lifting of heavy loads, awkward body postures, vibrations, noise, and extreme temperatures) was explored. Potential associations of individual and job characteristics with these factors of hardship at work were studied by multivariate logistic regression.ResultsIn total, 48% of employees were exposed to at least one physically demanding working condition and 24.8% were exposed to multiple constraints. While managers and intellectual professionals were exposed relatively infrequently to physical constraints, blue-collar workers experienced the highest frequency of exposure. On the one hand, the role of company size depended on the factor of hardship at work considered; on the other hand, employees in large-scale companies were generally less exposed. As expected, employees in the construction industry were the most exposed to physical constraints; that said, our results also show that some activities in the services sector (e.g., personal care, administrative and support services) were quite significantly affected by a wide array of physically demanding working conditions.ConclusionNotwithstanding the establishment in France of Plans de Santé au travail (preventive workplace health and safety plans), occupational risks were found to be high, and above all, they were unevenly distributed among the various socio-professional categories, and strongly contributed to social inequalities in health. Our results identify the types of publics to be designated as high-priority targets for preventive measures aimed at reducing the adverse impacts of physically demanding working conditions and the incidence of associated musculoskeletal disorders. 相似文献
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66.
Rena Fushiki Kotoe Mayahara Mai Ogawa Yasuyo Takahashi Yoko Karasawa Niina Tsurumachi 《Connective tissue research》2015,56(4):336-341
Purpose: Orthodontic tooth movement occurs during the bone remodeling induced by therapeutic mechanical strain. It is important to investigate the relation between the strength of mechanical stress and bone formation activity. The aim of this study was to determine the effect of high-magnitude mechanical strain on bone formation in detail.Materials and methods: Osteoblast-like cells isolated from fetal rat calvariae were loaded with 18% cyclic tension force (TF) for 48?h. To phenotypically investigate the effect of TF, we measured the number and the size of bone nodules stained by von Kossa technique on day 21 after cell seeding and determined the calcium content of bone nodules on day 14. Furthermore, we examined the gene expression of BMP-2, Runx2 and Msx2, which are important factors for bone nodule formation, on days 1, 4 and 7 after TF loading.Results: The maximum bone nodule size in the control group was 1620 and 719?μm in the TF group. Furthermore, the mean number of bone nodules sized over 360?μm in the TF group was significantly decreased compared to the control group. The calcium content was also significantly decreased to 42% by TF loading. The mRNA expression of BMP-2, Runx2 and Msx2 was decreased 1 and 4 days after TF loading.Conclusion: The differentiation of bone forming progenitor cells into bone nodule forming cells was inhibited by TF due to the decreased expression of bone formation related factors such as BMP-2, Runx2 and Msx2. 相似文献
67.
《中国现代医生》2020,58(31):130-133+141
目的 研究产褥感染的危险因素及常见致病微生物耐药情况,为临床治疗提供参考。方法 回顾性分析我院2017 年1 月~2019 年12 月发生的84 例产褥感染病例的临床资料,与同时期未发生产褥感染的200 例产妇进行对照研究,分析产褥感染的影响因素,并对分离获得的致病微生物进行耐药性分析。结果 感染组妊娠糖尿病、产钳助产、宫口开全后中转剖宫产患者的分布率高于对照组,差异有统计学意义(P<0.05);经多因素Logistic 回归分析,妊娠糖尿病是产褥感染的独立影响因素(P<0.05)。本研究中共检出致病微生物40 株,其中革兰阴性菌13 株(占32.50%),革兰阳性菌10 株(占25.00%),支原体16 株(占40.00%),衣原体1 株(占2.50%),革兰阴性菌中以大肠埃希菌最常见,对二代头孢菌素类抗生素耐药率20%。革兰阳性菌以金黄色葡萄球菌最常见,对青霉素及头孢菌素耐药率高,未发现对亚胺培南及万古霉素耐药。结论 产钳助产、妊娠糖尿病、宫口开全后中转剖宫产是产褥感染可能的危险因素,其中,妊娠糖尿病是产褥感染的独立危险因素。目前临床常见致病微生物谱及耐药率未发生明显变化。 相似文献
68.
Stereotactic body radiotherapy (SBRT) has become an important radiotherapy technology. In recent years, with the continuous improvement of the mechanical properties of the linear accelerator (LINAC), LINAC-based SBRT is gradually emerging. In this article, the history, technological progress, radiation physics, clinical application of LINAC-based SBRT were elaborated, aiming to promote the development of LINAC-based SBRT. 相似文献
69.
目的分析研究绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标的相关性。方法选取2013年10月至2017年05月于重庆医科大学附属第一医院内分泌内科住院的绝经后女性2型糖尿病患者385名。搜集其基本资料、骨代谢指标及骨密度等。根据T值将这些患者分为骨质疏松组(233例)、骨量减少组(101例)和骨量正常组(51例),比较三组间骨代谢指标的变化,并对骨密度(bone mineral density,BMD)与各项骨代谢指标进行相关性分析。结果 1型前胶原氨基末端前肽(Type I procollagen N-terminal propeptide,P1NP)、骨钙素(bone Gla protein,BGP)在骨质疏松组显著高于骨量减少组、骨量正常组(P0.05);随着骨密度的降低,1型胶原羧基端肽β特殊序列(β-Carboxyl terminal peptide,β-CTX)逐渐升高,骨质疏松组、骨量减少组与骨量正常组相比较差异有统计学意义(P0.05);Spearman等级相关分析示P1NP、BGP、β-CTX与骨密度呈负相关,25(OH)D_3与骨密度呈现正相关。结论绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标有一定的相关性,有助于预测骨折风险并及时抗骨质疏松治疗。 相似文献
70.
目的研究续筋接骨方治疗骨折的临床疗效。方法选取2018年1月—2018年6月在辽宁中医药大学附属第三医院就诊的骨折患者60例,所有患者按照随机数字表法分为对照组与观察组,每组30例。观察组口服续筋接骨方联合正骨后小夹板固定治疗,对照组患者采用正骨后小夹板固定治疗。分析2组患者干预3个月后的血清骨代谢指标、骨密度、生活质量改善情况以及疗效判定。结果干预前,2组的血清Ⅰ型前胶原羧基端肽β特殊序列(β-CTX)、血清Ⅰ型前胶原氨端肽原(PINP)、骨特异性碱性磷酸酶(ALP)水平、钙、磷及骨密度比较,差异无统计学意义(P>0.05);干预后,2组的β-CTX、PINP、骨特异性ALP水平、钙、磷及骨密度较干预前改善,观察组的改善效果优于对照组,差异均有统计学意义(P<0.05)。干预前,2组的物质生活、社会功能、躯体健康以及心理健康评分比较,差异无统计学意义(P>0.05);干预后,2组的物质生活、社会功能、躯体健康以及心理健康评分较干预前升高,观察组的各项生活质量评分高于对照组,差异均有统计学意义(P<0.05)。观察组的治疗恢复率高于对照组,差异有统计学意义(P<0.05)。结论续筋接骨方可以改善骨折患者骨代谢功能及生活质量。 相似文献