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81.
目的观察香烟烟雾提取物(CSE)对CD4^+T细胞向Th17细胞和调节性T细胞分化的影响,为探索香烟烟雾暴露导致气道慢性炎症的机制提供实验依据。方法采用免疫磁珠法分离纯化健康志愿者外周血CD4^+T细胞,以1×10^6/ml细胞密度接种于96孔培养板,分为以下8个组①空白对照组;②T细胞刺激剂组:加入T细胞刺激剂抗人CD3/28抗体微磁珠;③T细胞刺激剂CSE干预组:CD3/28+2%CSE;④细胞因子组:CD3/28+细胞因子;⑤细胞因子CSE干预组:CD3/28+细胞因子+2%CSE;⑥芳香烃受体(AHR)激动剂6-甲酰基吲哚[3,2-b]咔唑(FICZ)组CD3/28+细胞因子+FICZ;⑦AHR拮抗剂白藜芦醇组:CD3/28+细胞因子+2%CSE+白藜芦醇;⑧溶剂对照组:CD3/28+细胞因子+DMSO。细胞因子为含TGF-β/IL-1β/IL-6/IL~23的混合细胞因子,以诱导Th17细胞和调节性T细胞分化。培养5d后,收集细胞,采用流式细胞术检测细胞表面分子CD4^+CD25^+Foxp3^+细胞(Treg细胞),以及胞内细胞因子IL-17+的CD4^+T细胞(Th17细胞),计算各种刺激培养条件下,诱导生成的Th17及Treg细胞占CD4^+T细胞的百分比。结果①CSE对Th17细胞分化的影响:空白对照组Th17细胞比例为(0.69±0.12)%,加入T细胞刺激剂后为(1.32±0.12)%,在此基础上加入CSE的干预组IL-17+细胞比例升高为(2.17±0.24)%,(t=3.21,P〈0.01);细胞因子组IL-17+细胞比例为(1.35±0.08)%,而在此基础上加入CSE的干预组Th17细胞升高为(2.58±0.39)%(t=3.13,P〈0.01)。②CSE对Treg细胞分化的影响:在空白对照组中,Treg细胞占CD4^+T细胞中的比例为(0.21±0.19)%,在加入T细胞刺激剂后,Treg细胞比例升高(3.59±0.37)%,加入细胞因子后,Treg细胞比例明显增加(5.85±0.76)%;在继续加入CSE干预后,Treg细胞比例明显减少(3.07±0.33)%(t=3.74,P〈0.01);同样,T细胞刺激剂CSE干预组也出现Treg细胞比例减少(2.19±0.19)%,(t=2.71,P〈0.05)。③AHR活化对Treg细胞和Th17细胞分化的影响:AHR激动剂FICZ组的Treg细胞比例明显低于细胞因子组[(2.60±0.40)%,(5.85±0.76)%](t=4.18,P〈0.01),但Th17细胞比例升高[(2.86±0.43)%,(1.35±0.08)%](t=3.65,P〈0.01)。AHR阻断剂白藜芦醇组中的Treg细胞比例和Th17细胞比例均低于细胞因子组,分别为[(0.33±0.14)%,(5.85±0.76)%],(t=7.71,P〈0.01)和[(0.42±0.07)%,(1.35±0.08)%],(t=8.87,P〈0.001),并且和空白对照组接近,在细胞培养第5天通过7-AAD-AnnexinV对该组细胞检测并未发现细胞异常凋亡或死亡情况,结合该组细胞培养过程中的镜下形态推测该实验组CD4^+T细胞的分化增殖受到白藜芦醇抑制。结论CSE可促进CD4^+T细胞向Th17细胞分化,并抑制Treg细胞分化,这一过程可能通过AHR诱导。  相似文献   
82.
Background: The authors investigated the relationship between objectively assessed tobacco smoke exposure and periodontal disease. Methods: This cross‐sectional study included 1,103 women with a mean age of 31.5 years. Information on potential confounding factors was obtained through a self‐administered questionnaire. Periodontal disease was defined as positive if a woman had at least one tooth with a probing depth of ≥3.5 mm. Exposure to tobacco smoke was determined based on salivary cotinine concentration. Adjustment was made for age, region of residence, household income, education, toothbrushing frequency, and use of an interdental brush. Results: The prevalence of periodontal disease was 11.3%. Salivary cotinine concentration was independently positively associated with the prevalence of periodontal disease: the adjusted odds ratio for every 1‐unit (ng/mL) increase in salivary cotinine was 1.004 (95% confidence interval: 1.000 to 1.007). Conclusion: Salivary cotinine concentrations were positively associated with the prevalence of periodontal disease among young women.  相似文献   
83.
84.
Aims To examine the association of person‐specific trajectories of withdrawal symptoms of urge‐to‐smoke, negative affect, physical symptoms and hunger during the first 7 days after smoking cessation with abstinence at end of treatment (EOT) and at 6 months. Design Hierarchical linear modeling (HLM) was used to model person‐specific trajectory parameters (level, slope, curvature and volatility) for withdrawal symptoms. Setting University‐based smoking cessation trials. Participants Treatment‐seeking smokers in clinical trials of transdermal nicotine versus nicotine spray (n = 514) and bupropion versus placebo (n = 421). Measurements Self‐reported withdrawal symptoms for 7 days after the planned quit date, and 7‐day point prevalence and continuous abstinence at EOT and 6 months. Findings In regressions that included trajectory parameters for one group of withdrawal symptoms, both urge‐to‐smoke and negative affect were predictive of abstinence while physical symptoms and hunger were generally not predictive. In stepwise regressions that included the complete set of trajectory parameters across withdrawal symptoms (for urge‐to‐smoke, negative affect, physical symptoms and hunger), with a single exception only the trajectory parameters for urge‐to‐smoke were predictive. Area under the receiver operator characteristic curve was 0.594 for covariates alone, and 0.670 for covariates plus urge‐to‐smoke trajectory parameters. Conclusions Among a number of different withdrawal symptoms (urge‐to‐smoke, negative affect, physical symptoms and hunger) urge‐to‐smoke trajectory parameters (level, slope and volatility) over the first 7 days of smoking cessation show the strongest prediction of both short‐ and long‐term relapse. Other withdrawal symptoms increase the predictive ability by negligible amounts.  相似文献   
85.
Purpose:The study uses principles of liquid and gas mechanics to verify and quantify the generation of aerosols in oculoplastic procedures, namely surgery using a scalpel, electrosurgical device, and a mechanized drill.Methods:Surgical techniques were performed ex vivo using the electrosurgical device, scalpel, and mechanized drill on the muscle and bone of commercially available chicken. The liquid and gas dynamics were observed using a high-speed high-resolution Photron SA5 camera (0.125 to 8 ms temporal resolution, 0.016 to 0.054 mm/pixel spatial resolution) and stroboscopic lighting (Veritas 120 E LED Constellation). The analysis was performed using in-house algorithms and ImageJ software.Results:The use of a mechanized drill at 35000 rpm and a 3 mm fluted burr generated aerosol with particle size 50 to 550 microns with a spread of 1.8 m radius. Surgical smoke was generated by an electrosurgical device in both cutting and coagulation modes. Dispersion of the smoke could be controlled significantly by the use of suction, mean smoke spread ratio being 0.065 without suction and 0.002 with use of suction within 2 cm.Conclusion:The quantification of the aerosol generation will help surgeons take practical decisions in their surgical techniques in the pandemic era.  相似文献   
86.

Objective

Previous population-based studies suggest that exposure to secondhand smoke (SHS) is related to increased depressive symptoms and poor mental health among non-smokers. We examined whether these associations could be replicated in two independent Dutch samples.

Methods

Non-smoking adults were selected from two studies: 1) the Netherlands Study of Depression and Anxiety (NESDA), comprising individuals with current and remitted depressive and/or anxiety disorders, and healthy controls and 2) the Netherlands Twin Register (NTR), comprising twin-family studies on health-related behaviors. In both studies, SHS exposure was assessed with plasma cotinine levels (1–14 ng/ml vs. < 1 ng/ml). In NESDA, outcomes were current depressive and/or anxiety disorders, and depression and anxiety symptom severity scores. In NTR, the Adult Self Report derived DSM-subscales for depressive and anxiety problems, and anxious depressive scores were analyzed.

Results

In NESDA non-smokers (n = 1757), increased plasma cotinine level (≥ 1 ng/ml) was not related to current depressive and/or anxiety disorders [odds ratio (OR) 0.96, P = .77], nor to depression or anxiety severity indicators. Similarly, in NTR non-smokers (n = 1088) cotinine levels ≥ 1 ng/ml were not associated with the DSM-subscale for depressive problems [unstandardized regression coefficient (B) 0.04, P = .88], nor to other depression and anxiety measures.

Conclusions

In non-smoking adults from patient and population samples, we found no evidence that plasma cotinine levels were related to either depressive and/or anxiety disorders, or to depressive and anxiety symptoms. This suggests that SHS exposure is not related to depression and anxiety in non-smoking adults.  相似文献   
87.
88.
Maternal smoking during the perinatal period is linked to adverse neonatal outcomes such as low birth weight and birth defects. Numerous studies have shown that cigarette smoke or nicotine exposure has a widespread effect on fetal nerve development. However, there exists a lack of understanding of what specific changes occur at the cellular level on persistent exposure to cigarette smoke during the differentiation of embryonic stem cells (ESCs) into neural cells. We previously investigated the effects of cigarette smoke extract (CSE) and its major component, nicotine, on the neural differentiation of mouse embryonic stem cells (mESCs). Differentiation of mESCs into neural progenitor cells (NPCs) or neural crest cells (NCCs) was induced with chemically defined media, and the cells were continuously exposed to CSE or nicotine during neural differentiation and development. Disturbed balance of the pluripotency state was observed in the NPCs, with consequent inhibition of neurite outgrowth and glial fibrillary acidic protein (Gfap) expression. These inhibitions correlated with the altered expression of proteins involved in the Notch-1 signaling pathways. The migration ability of NCCs was significantly decreased by CSE or nicotine exposure, which was associated with reduced protein expression of migration-related proteins. Taken together, we concluded that CSE and nicotine inhibit differentiation of mESCs into NPCs or NCCs, and may disrupt functional development of neural cells. These results imply that cigarette smoking during the perinatal period potentially inhibits neural differentiation and development of ESCs cells, leading to neonatal abnormal brain development and behavioral abnormalities.  相似文献   
89.
BACKGROUND Electrosurgical smoke could be different by the device of cutting or the type of tissue that is being cut.AIM To analyze the electrocautery smoke released from the tissues that are frequently cut in orthopedic surgeries.METHODS The released smoke from electrocautery of five different tissue types(meniscus,ligament,adipose,muscle,and synovium) of five patients who underwent total knee arthroplasty were collected and analyzed for volatile organic compounds(VOCs) and 27 candidate polycyclic aromatic hydrocarbons(n = 25).Surgical smoke was produced with an electrocautery device for 4 min.RESULTS None of the 27 evaluated polycyclic aromatic hydrocarbons compounds were detectable in electrocautery smoke collected from the surgical cutting of the different tissues.The number and identity of detected VOCs were similar between the patients but not between tissue types.The number of detected VOCs was the highest in synovial tissue(n = 21) and the lowest in the meniscus and adipose tissue(n = 12).The number of toxic and/or carcinogenic VOCs were the most in the muscle and meniscus tissues(Toluene,Ethylbenzene,and Styrene).No toxic and/or carcinogenic VOCs were identified in the ligament and adipose tissue.CONCLUSION Meniscus and muscle tissue are associated with the highest number of toxic and/or carcinogenic VOCs.Therefore,we recommend that surgeons avoiding the electrocautery of these tissues.  相似文献   
90.
目的 探讨环境烟草烟雾(enviromental tobacco smoke,ETS)对小鼠泪膜功能和角膜上皮组织结构的影响。方法 选取SPF级c57BL雄性小鼠12只,随机分为对照组和ETS干预组,每组6只。对照组不进行ETS干预,ETS干预组进行ETS干预,每天2次,一次30 min,干预12周。在干预前及干预后对各组小鼠进行泪膜功能检测,包括泪膜破裂时间、荧光素染色(FL)评分;干预后摘取小鼠角膜组织,行HE染色,在光学显微镜下观察小鼠角膜上皮结构变化情况。结果 干预12周后,对照组泪膜破裂时间和FL评分与干预前相比,差异均无统计学意义(均为P>0.05);而ETS干预组泪膜破裂时间较干预前明显缩短,FL评分较干预前明显增加,差异均有统计学意义(均为P<0.05)。ETS干预组干预12周后泪膜破裂时间较对照组明显缩短,FL评分较对照组明显增加,差异均有统计学意义(均为P<0.05);两组干预前泪膜破裂时间和FL评分差异均不明显(均为P>0.05)。FL染色结果显示:干预12周后,对照组小鼠角膜上皮完整,角膜染色呈阴性;ETS干预组整个角膜上皮荧光素着染区域明显增加,呈点片状。HE染色结果显示:干预12周后,对照组未见角膜上皮层数的改变,厚度也基本未变,基底细胞仍为单层柱状上皮细胞,表层上皮较完整;ETS干预组可见角膜上皮细胞层数增多,厚度增加,细胞排列紊乱,表层上皮细胞有损失及脱落,角膜表面不光滑。干预前对照组小鼠上皮细胞为(5±1)层,干预后基本不变;ETS干预组干预后为(7±1)层;干预后两组上皮细胞层数比较差异有统计学意义(P<0.05)。结论 ETS会影响小鼠泪膜功能,损伤小鼠角膜上皮的组织结构。  相似文献   
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