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51.
The purpose of the current study was to determine if saliva contains biomarkers that can be used as diagnostic tools for Sj?gren's syndrome (SjS). Twenty seven SjS patients and 27 age-matched healthy controls were recruited for these studies. Unstimulated glandular saliva was collected from the Wharton's duct using a suction device. Two μl of salvia were processed for mass spectrometry analyses on a prOTOF 2000 matrix-assisted laser desorption/ionization orthogonal time of flight (MALDI O-TOF) mass spectrometer. Raw data were analyzed using bioinformatic tools to identify biomarkers. MALDI O-TOF MS analyses of saliva samples were highly reproducible and the mass spectra generated were very rich in peptides and peptide fragments in the 750-7,500 Da range. Data analysis using bioinformatic tools resulted in several classification models being built and several biomarkers identified. One model based on 7 putative biomarkers yielded a sensitivity of 97.5%, specificity of 97.8% and an accuracy of 97.6%. One biomarker was present only in SjS samples and was identified as a proteolytic peptide originating from human basic salivary proline-rich protein 3 precursor. We conclude that salivary biomarkers detected by high-resolution mass spectrometry coupled with powerful bioinformatic tools offer the potential to serve as diagnostic/prognostic tools for SjS.  相似文献   
52.
目的:对蒙药苏格木勒-3水提物进行化学成分研究,构建较为全面的化学成分谱,为苏格木勒-3水提物有效物质基础研究奠定基础。方法:采用超高液相色谱串联四级杆飞行时间质谱(UPLC-Q-TOF-MS)技术,使用ESI离子源,通过mzCloud与mzVoult软件以及质谱裂解规律,并结合对照品及相关文献资料比对进行定性分析。结果:经过分析,从蒙药苏格木勒-3水提物中共鉴定出42个成分,主要包括氨基酸、酚酸类、黄酮类、内酯类、生物碱类及其他类等6类成分,并对各成分的药材来源进行归属。结论:本研究全面、快速、准确地分析了蒙药苏格木勒-3水提物的化学成分,为其药效物质基础和质量控制等研究奠定了基础。  相似文献   
53.
珠娜  萨茹拉  那生桑 《中国现代中药》2015,17(11):1164-1166
目的:优选小白蒿蒙医炮制工艺,并观察其饮片安全有效性。方法:以炮制品绿原酸含量为主要指标并参考槲皮素含量进行正交试验,以考察炒制温度、时间和药材粒度的影响,确定最佳工艺;采用小白鼠急性毒性实验,断尾实验测定出血时间,眼眶静脉丛取血测定凝血时间,断头采全血计数血小板总数,评价安全有效性。结果:本品在270℃温度下翻动炒制20 min效果最佳,经方差分析证明炒制温度、时间和粒度因素对所监测的两种成分的含量均没有显著影响;小白蒿炮制后可缩短小白鼠的出血时间,显著增高血小板计数。结论:小白蒿经过合理的炒制后,可提高其安全性和止血药效,为验证传统蒙药小白蒿用药理论,提供了参考依据。  相似文献   
54.
The epidermal permeability barrier of premature infants matures rapidly following birth. Previous studies suggest that air exposure could contribute to this acceleration, because: (i) development of a structurally and functionally mature barrier accelerates when fetal rat skin explants are incubated at an air-medium interface, and (ii) occlusion with a water-impermeable membrane prevents this acceleration. To investigate further the effects of air exposure on epidermal barrier ontogenesis, we compared the activities of several key enzymes of lipid metabolism and gene expression of protein markers of epidermal differentiation in fetal rat skin explants grown immersed versus air exposed. The rate-limiting enzymes of cholesterol (HMG CoA reductase) and ceramide (serine palmitoyl transferase) synthesis were not affected. In contrast, the normal developmental increases in activities of glucosylceramide synthase and cholesterol sulfotransferase, responsible for the synthesis of glucosylceramides and cholesterol sulfate, respectively, were accelerated further by air exposure. Additionally, two enzymes required for the final stages of barrier maturation and essential for normal stratum corneum function, beta-glucocerebrosidase, which converts glucosylceramide to ceramide, and steroid sulfatase, which desulfates cholesterol sulfate, also increased with air exposure. Furthermore, filaggrin and loricrin mRNA levels, and filaggrin, loricrin, and involucrin protein levels all increased with air exposure. Finally, occlusion with a water-impermeable membrane prevented both the air-exposure-induced increase in lipid enzyme activity, and the expression of loricrin, filaggrin, and involucrin. Thus, air exposure stimulates selected lipid metabolic enzymes and the gene expression of key structural proteins in fetal epidermis, providing a biochemical basis for air-induced acceleration of permeability barrier maturation in premature infants.  相似文献   
55.
Liver X receptor-alpha and -beta are members of the nuclear hormone receptor superfamily that heterodimerize with retinoid X receptor and are activated by oxysterols. In recent studies we found that treatment of cultured human keratinocytes with oxysterolstimulated differentiation, as demonstrated by increased expression of involucrin and transglutaminase, and inhibited proliferation. The aims of this study were to determine: (i) whether oxysterols applied topically to the skin of mice induce differentiation in normal epidermis; (ii) whether this effect is mediated via liver X receptor-alpha and/or liver X receptor-beta; and (iii) whether oxysterols normalize epidermal morphology in an animal model of epidermal hyperplasia. Topical treatment of normal hairless mice with 22(R)-hydroxycholesterol or 24(S),25-epoxycholesterol resulted in a decrease in epidermal thickness and a decrease in keratinocyte proliferation assayed by proliferating cell nuclear antigen staining. Moreover, oxysterol treatment increased the levels of involucrin, loricrin, and profilaggrin protein and mRNA in the epidermis, indicating that oxysterols stimulate epidermal differentiation. Additionally, topical oxysterol pretreatment improved permeability barrier homeostasis. Whereas liver X receptor-alpha-/- mice revealed no alterations in epidermal differentiation, the epidermis was thinner in liver X receptor-beta-/- mice than in wild-type mice, with a reduced number of proliferating cell nuclear antigen positive cells and a modest reduction in the expression of differentiation markers. Topical oxysterol treatment induced differentiation in liver X receptor-alpha-/- mice whereas in liver X receptor-beta-/- mice there was no increase in the expression of differentiation markers. Whereas both liver X receptor-alpha and liver X receptor-beta are expressed in cultured human keratinocytes and in fetal rat skin, only liver X receptor-beta was observed on northern blotting in adult mouse epidermis. Finally, treatment of hyperproliferative epidermis with oxysterols restored epidermal homeostasis. These studies demonstrate that epidermal differentiation is regulated by liver X receptor-beta and that oxysterols, acting via liver X receptor-beta, can induce differentiation and inhibit proliferation in vivo. The ability of oxysterols to reverse epidermal hyperplasia suggests that these agents could be beneficial for the treatment of skin disorders associated with hyperproliferation and/or altered differentiation.  相似文献   
56.
Veterans experience chronic pain at greater rates than the rest of society and are more likely to receive long-term opioid therapy (LTOT), which, at high doses, is theorized to induce maladaptive neuroplastic changes that attenuate self-regulatory capacity and exacerbate opioid dose escalation. Mindfulness meditation has been shown to modulate frontal midline theta (FMT) and alpha oscillations that are linked with marked alterations in self-referential processing. These adaptive neural oscillatory changes may promote reduced opioid use and remediate the neural dysfunction occasioned by LTOT. In this study, we used electroencephalography (EEG) to assess the effects of a mindfulness-based, cognitive training intervention for opioid misuse, Mindfulness-Oriented Recovery Enhancement (MORE), on alpha and theta power and FMT coherence during meditation. We then examined whether these neural effects were associated with reduced opioid dosing and changes in self-referential processing. Before and after 8 weeks of MORE or a supportive psychotherapy control, veterans receiving LTOT (N = 62) practiced mindfulness meditation while EEG was recorded. Participants treated with MORE demonstrated significantly increased alpha and theta power (with larger theta power effect sizes) as well as increased FMT coherence relative to those in the control condition—neural changes that were associated with altered self-referential processing. Crucially, MORE significantly reduced opioid dose over time, and this dose reduction was partially statistically mediated by changes in frontal theta power. Study results suggest that mindfulness meditation practice may produce endogenous theta stimulation in the prefrontal cortex, thereby enhancing inhibitory control over opioid dose escalation behaviors.Subject terms: Human behaviour, Addiction  相似文献   
57.
Environmental exposure to tobacco smoke and lung function in young adults   总被引:10,自引:0,他引:10  
The relationship between lung function and environmental exposure to tobacco smoke (passive smoking) was studied in 293 nonsmoking young men and women, 15 to 35 yr of age. A self-administered mailed questionnaire was used to assess the lifetime environmental exposure to cigarette smoke at home and at work for each subject. Lung function information used here had been gathered in the course of a previous study of the determinants of lung function in early adulthood. In men, maximal midexpiratory flow rate (FEF25-75) decreased in relation to an index of cumulative lifetime environmental exposure to tobacco smoke at home, after taking into account the effects of cumulative exposure at work as well as age, height, body size, respiratory pressures, and cooking fuels used at home. The components of this exposure index most closely related to the reduction in FEF25-75 were maternal smoking habits and exposure to second-hand smoke during childhood. In women, the diffusing capacity of the lung (DLCO) decreased in relation to cumulative exposure to tobacco smoke at work, after accounting for the effects of cumulative lifetime exposure at home and the other factors mentioned above. These findings contribute to the gathering evidence that environmental exposure to tobacco smoke is harmful to respiratory health, and suggest that the effects are not insignificant. For instance, the FEF25-75 of a young man 20 yr of age who had never smoked and always lived at home would be 800 ml less if both his parents smoked than if they did not.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Spirometric test failure has been defined as failure by a subject to meet the acceptability and/or reproducibility criteria laid down by the American Thoracic Society for measurements derived from forced expiratory maneuvers. The prevalence and determinants of spirometric test failure were examined in 416 men and women aged 20 to 45 yr working in an office environment. In this study population, 11.5% (28 men and 20 women) exhibited test failure for forced expiratory volume in one second (FEV1). The main determinant of test failure in men was bronchial hyperresponsiveness to methacholine challenge (odds ratio 6.7; confidence interval 1.7, 27.1) and in women being a current smoker (odds ratio 4.02; confidence interval 1.13, 14.33). There was also a relationship to eczema in both men and women, but not at a statistically significant level. When FEV1 variability was defined as the difference (in milliliters) between the two best FEV1 values and the results of men and women combined for analysis, significant predictors were a history of eczema, recurrent chest illness in the past 3 yr, and level of bronchial responsiveness to inhaled methacholine. These findings contribute to the gathering evidence that test failure may be of itself an indicator of impaired respiratory health, and its association with bronchial hyperresponsiveness to methacholine in men suggests that in them test failure is related to airway lability, but in women the relationship to smoking suggests an irritative mechanism.  相似文献   
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