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71.
Tumor necrosis factor-alpha (TNF-α) has been implicated in the pathogenesis of several non-infectious and infectious diseases including tuberculosis. In a prospective longitudinal study, TNF-α level in blood was estimated by sandwich ELISA using anti human TNF-α antibody, in 22 patients with active pleuro-pulmonary and lymphnode tuberculosis before and after chemotherapy and 8 healthy controls. Six patients and six controls had detectable levels (> 5 pg/ml) of TNF-α in blood. The mean TNF-α levels in controls and cases before and after treatment were 182.4pg/ml, 896.7 pg/ml and 678.7pg/ml pg/ml respectively. Though not statistically significant, there was a trend towards younger age, shorter duration of symptoms, presence of fever and anorexia, and high ESR, in patient with high serum TNF-α levels.  相似文献   
72.
Herein, we report the case of a 42-year-old woman, hospitalized in a French tertiary hospital for a relapse of a chronic enteropathy, who was found on admission to have no detectable serum transferrin. Surprisingly, she only exhibited mild anaemia. This atransferrinemia persisted for two months throughout her hospitalization, during which her haemoglobin concentration remained broadly stable. Based on her clinical history and evolution, we concluded to an acquired atransferrinemia secondary to chronic undernutrition, inflammation and liver failure. We discuss the investigations performed in this patient, and hypotheses regarding the relative stability of her haemoglobin concentration despite the absence of detectable transferrin.  相似文献   
73.
This study examined the effects of beetroot juice on the repeated bout effect (RBE) to eccentric exercise. Twenty-nine recreationally active males performed two bouts of 100-drop jumps, separated by 14–21 days. Using a double-blind, independent groups design, participants consumed either a higher dose beetroot juice (H-BT; 250 ml, n = 10), a lower dose beetroot juice (L-BT; 125 ml, n = 9) or an isocaloric placebo (PLA; 250 ml, n = 10) for 3 days after bout 1; no drinks were consumed after bout 2. Maximal isometric voluntary contraction (MIVC), countermovement jump (CMJ), pressure-pain threshold (PPT) and creatine kinase (CK) were measured pre, post, 24, 48 and 72 h following both bouts. In bout 2, CMJ and MIVC recovered quicker and CK activity was attenuated (versus bout 1) (P < 0.05) in all groups, demonstrating an RBE. At 24 h post bout 1, MIVC was 84.1 ± 16.1, 83.6 ± 11.6, 79.7 ± 15.1% relative to baseline values in the H-BT, L-BT and PLA groups, respectively; at 24 h post bout 2, MIVC recovered to 90.7 ± 13.7, 92.9 ± 6.9, 87.8 ± 6.9, in the H-BT, L-BT and PLA groups, respectively. These findings suggest that supplementation with antioxidant-rich beetroot juice does not adversely affect acute adaptations to a bout of eccentric exercise.  相似文献   
74.
The aim of this study was to examine upper respiratory tract infections (URTI) and their associations with resting saliva and blood immune and endocrine parameters in ice hockey players. Twenty-seven participants (age 16.5 ± 0.5 years) completed the 24-week study period. The counts/concentrations of immune and endocrine markers were compared between healthy-prone athletes (≤2 episodes of URTI during the study period) and illness-prone athletes (≥3 episodes of URTI) and between the URTI state (when athletes had infections) and the healthy state (the time without URTI). There were no differences in concentration/counts of saliva and blood immune and endocrine parameters between the illness-prone and illness-free athletes. Athletes had significantly lower sIgA, sIgA1 and sIgA2 concentrations (sIgA: 119.88 ± 66.88, 144.10 ± 75.0 µg/ml; sIgA1: 90.2 ± 40.64, 108.44 ± 29.8 U; sIgA2: 67.58 ± 30.1, 80.3 ± 25.61 U, respectively) and significantly higher WBC, neutrophil, monocyte and eosinophil count values and IL-1ra concentration at the time when they had symptoms of URTI than in the period without symptoms of infections. There were no differences in salivary cortisol concentration between the period of URTI symptoms and the period without URTI symptoms. In conclusion, we observed lower concentrations of salivary immunoglobulins and higher levels of blood immune parameters during URTI in athletes, which may confirm the suppression of mucosal immunity and initiation responses to pathogenic infections by innate immunity.  相似文献   
75.
Plasma heat shock protein 70 (HSP70) concentrations rise during heat stress, which can independently induce cytokine production. Upper body exercise normally results in modest body temperature elevations. The aim of this study was to investigate the impacts of additional clothing on the body temperature, cytokine and HSP70 responses during this exercise modality. Thirteen males performed 45-min constant-load arm cranking at 63% maximum aerobic power (62 ± 7%V?O2peak) in either a non-permeable whole-body suit (intervention, INT) or shorts and T-shirt (control, CON). Exercise resulted in a significant increase of IL-6 and IL-1ra plasma concentrations (< 0.001), with no difference between conditions (> 0.19). The increase in HSP70 from pre to post was only significant for INT (0.12 ± 0.11ng?mL?1, < 0.01 vs. 0.04 ± 0.18 ng?mL?1, = 0.77). Immediately following exercise, Tcore was elevated by 0.46 ± 0.29 (INT) and 0.37 ± 0.23ºC (CON), respectively (< 0.01), with no difference between conditions (= 0.16). The rise in mean Tskin (2.88 ± 0.50 and 0.30 ± 0.89ºC, respectively) and maximum heat storage (3.24 ± 1.08 and 1.20 ± 1.04 J?g?1, respectively) was higher during INT (< 0.01). Despite large differences in heat storage between conditions, the HSP70 elevations during INT, even though significant, were very modest. Possibly, the Tcore elevations were too low to induce a more pronounced HSP70 response to ultimately affect cytokine production.  相似文献   
76.
Purpose: This study examined postexercise inflammatory and leukocyte responses in smokers and nonsmokers, as well as the effects of cigarette smoking on the acute postexercise inflammatory and leukocyte response in habitual smokers. Method: Eleven recreationally active male smokers and 11 nonsmokers matched for age and aerobic fitness were familiarized and underwent baseline fitness testing. Participants then completed 40 min of cycling at 50% peak aerobic workload. Smokers performed 2 randomized exercise sessions, including an acute postexercise smoking condition (2 cigarettes in 15 min of 12 mg tar and 1 mg nicotine) and a no-smoking condition, while nonsmokers performed 1 exercise session without smoking. Venous blood was obtained preexercise and postexercise for analysis of interleukin (IL)-6, IL-1 receptor antagonist (ra), tumor necrosis factor-alpha (TNF-α), and c-reactive protein (CRP). Results: No differences existed between groups for resting CRP (d = 0.25–0.46; p = .374–.617). Despite no baseline difference (d = 0.03–0.07; p = .141–.70), exercise-induced increases were observed for IL-1 ra in smokers (d = 0.50; p = .024–.033), which was not observed in the never-smoker group. No between-group difference was observed for IL-6 across all points (d = 0.09–0.5; p = .102–.728); however, all groups observed significant within-group change (d = 0.27–1.09; p = .001–.042). Further, TNF-α for smokers smoking was elevated above both smokers not smoking and nonsmokers at baseline and across the protocol (d = 1.20–1.80; d = 0.20–1.0; p = .001–.035). Additionally, a marked postexercise increase in leukocyte and neutrophil concentrations was evident in smokers smoking compared with nonsmokers and smokers not smoking as indicated by a moderate-to-large effect size (d = 0.72; d = 0.78). Conclusion: Consequently, male smokers exhibit an altered postexercise proinflammatory profile compared with age- and fitness-matched nonsmokers.  相似文献   
77.
1IntroductionHyper-IgMsyndrome(HIM)isarareimmunodeficiencycharacterizedbyanincreasedsusceptibilitytorecurrentinfectionsandmar...  相似文献   
78.
目的:放创复合伤是一种以血管损伤和促炎细胞因子缺乏为特征的难愈性创伤。瘦素(leptin)的直接应用在血管生成和炎症中起着重要作用。本研究构建了一种可持续稳定的leptin表达系统——leptin修饰的人胎盘来源间充质干细胞(HPMSCs/leptin),并探究其对经X射线辐照后的人脐静脉内皮细胞(HUVECs)的成血管潜能及周围炎症的影响和潜在机制。创新点:可持续稳定的leptin表达系统(HPMSCs/leptin)促进受X射线辐照后HUVECs的成血管潜能及外周炎症反应,有助于解决放创复合伤伤口愈合过程中血管损伤和促炎因子缺乏的问题。方法:利用慢病毒载体将leptin基因转染HPMSCs获得HPMSCs/leptin。采用X射线单次照射HUVECs,剂量为20 Gy。细胞迁移侵袭实验技术(Transwell)检测照射后HUVECs的迁移情况。在Transwell体系的基础上,建立HPMSCs与受辐照HUVECs共培养体系。CCK-8比色法测定细胞增殖。酶联免疫吸附法(ELISA)检测促炎细胞因子(粒细胞-巨噬细胞集落刺激因子(GM-CSF)、白细胞介素-1α(IL-1α)、IL-6和IL-8)的分泌。实时荧光定量聚合酶链式反应(RT-qPCR)检测促血管生成因子(VEGF和bFGF)mRNA的表达。蛋白免疫印迹法(westernblot)检测核因子κB(NF-κB)和JAK/STAT信号通路的相关分子表达。结论:可持续稳定的leptin表达系统(HPMSCs/leptin)具有更好的细胞增殖、迁移和成血管潜能。HPMSCs/leptin单独培养和HPMSCs/leptin与受辐照HUVECs共培养体系中,促炎细胞因子的分泌增加与NF-κB和JAK/STAT信号通路的相互作用有关。HPMSCs/leptin可能促进X射线照射后HUVECs的成血管潜能和外周炎症反应。  相似文献   
79.
对根管预备后出现根尖炎反应的原因进行分析。方法常规根管预备法,对不同年龄组及牙位组进行比较分析。结果青年组及前牙组根管预备后出现根尖炎性反应较中老年组及后牙组少。讨论根管预备必须严格按照无菌操作及逐步后退法,尽量避免机械性损伤根尖周组织,一边制备,一边冲洗,将感染物质冲出根管,才能减少根尖炎性反应的发生。  相似文献   
80.
Abstract

The objective of the present study was to monitor the immunological and hormonal responses and the occurrence of upper respiratory symptoms in adolescent basketball athletes during the different stages of a sports season. Anthropometric measures, biochemical analyses (interleukin-6, interleukin-10, tumour necrosis factor-alpha, C-reactive protein, testosterone and cortisol), neuromuscular evaluations (standing vertical jumping ability, agility and estimated VO2max) and leukocyte counts were performed at four moments: 72 h before the season (?72 h); before the season (Pre-season); after six weeks, at the end of the preparatory period (Preparatory); and after 20 weeks, at the end of the competitive period (Competitive). Also, the occurrence of upper respiratory symptoms was collected weekly during all stages of the season. There were significant increases in monocytes, cortisol, tumour necrosis factor-alpha and C-reactive protein at the Competitive moment as compared to the Pre-season. In addition, interleukin-10 decreased at the Competitive moment as compared to the Pre-season. Occurrence of upper respiratory symptoms demonstrated increases (38%) during the competitive period as compared to the preparatory. These results suggest that periods of training and competition could increase the occurrence of upper respiratory symptoms in adolescent athletes and this may be due to the unwanted effects of an inflammatory process in response to the excessive stress of training and competition.  相似文献   
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