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991.
《HIV clinical trials》2013,14(1):41-47
Abstract

Purpose: The objective of this study was to examine lamivudine (3TC), zidovudine (ZDV), nelfinavir (NFV), and its active nelfinavir metabolite (M8) concentrations in paired maternal plasma and amniotic fluid samples to determine antiretroviral penetration or accumulation in the fetal compartment. Method: Ten paired amniotic fluid and maternal plasma samples were obtained during caesarian section for pharmacokinetic analysis. Antiretroviral concentrations were measured in both matrices using high-performance liquid chromatography (HPLC) and mass spectrometry (LC/MS) methodologies. Results: Median maternal plasma concentrations for NFV, M8, 3TC, and ZDV were 456, 244, 176, and 794 ng/mL, respectively, while median amniotic fluid concentrations were 118, 21, 2537, and 1483 ng/mL, respectively. The median NFV amniotic fluid to maternal plasma ratio was 0.44; the median M8 ratio was 0.11. Median 3TC and ZDV amniotic fluid to plasma ratios were 11.9 and 1.5, respectively. Conclusions: NFV and M8 exhibited partial drug transfer and/or accumulation in the amniotic compartment, whereas ZDV and 3TC concentrations mostly exceeded that in maternal plasma. Overall, all drugs achieved exposures in the amniotic fluid in excess of their wild-type viral susceptibilities. Amniotic fluid is an important compartment in the prevention of mother-to-child transmission; a further understanding of protease inhibitor and other antiretroviral drug penetration into amniotic fluid is warranted.  相似文献   
992.
目的探讨如何处理羊水细胞培养中出现的嵌合现象。方法收集2007年1月至2011年6月因各种产前诊断指征行羊膜腔穿刺及染色体检查检出为嵌合体病例共27例。统计嵌合体检出率、类型、相应脐带血分析结果,并对所有病例进行出生后随访。结果嵌合体发生率为0.69%。其中,性染色体XX/XY嵌合体11例(占40.74%);数目异常嵌合体13例(占48.15%);结构异常3例(占11.11%)。其中14例行脐血染色体检查,确诊为真性嵌合体1例,终止妊娠;未行脐血染色体检查13个病例中,除2例失访外,余均正常分娩,出生随访未见异常。结论产前诊断羊水细胞嵌合体多为假性嵌合体,各种类型的假性嵌合体一般预后均良好。正确处理和判断羊水细胞培养中出现的嵌合现象,对产前诊断和遗传咨询具有重要的意义。  相似文献   
993.
目的分析比较高分子止血海绵和鼻腔止血器在鼻内镜术后的止血效果。方法选取100例需要进行鼻腔、鼻窦手术患者,其中男性76例,女性24例;年龄18~60岁,中位年龄36岁。随机分为2组,试验组50例,对照组50例。在术后分别放置高分子止血海绵和鼻腔止血器,观察患者的疼痛反应和止血效果,并对比取出填塞物时的难易程度及出血量,进行对比分析。结果两者止血效果相当,试验组少量渗血36例,对照组29例;两组无出血病例;止血效果两组差异无统计学意义(P0.05)。试验组无痛、轻度疼痛各26、24例,对照组各3、44例。试验组填塞物容易取出46例,对照组21例。两组在鼻腔胀痛、头痛、抽出时难易程度、抽出时出血量方面的差异均有统计学意义(P0.05),均显示试验组的效果优于对照组。结论鼻腔止血器不良反应少,临床效果优于高分子止血海绵填塞,值得广泛推广。  相似文献   
994.
Background: Hypoplastic left heart syndrome (HLHS) is a major human congenital heart defect that results in single ventricle physiology and high mortality. Clinical data indicate that intracardiac blood flow patterns during cardiac morphogenesis are a significant etiology. We used the left atrial ligation (LAL) model in the chick embryo to test the hypothesis that LAL immediately alters intracardiac flow streams and the biomechanical environment, preceding morphologic and structural defects observed in HLHS. Results: Using fluorescent dye injections, we found that intracardiac flow patterns from the right common cardinal vein, right vitelline vein, and left vitelline vein were altered immediately following LAL. Furthermore, we quantified a significant ventral shift of the right common cardinal and right vitelline vein flow streams. We developed an in silico model of LAL, which revealed that wall shear stress was reduced at the left atrioventricular canal and left side of the common ventricle. Conclusions: Our results demonstrate that intracardiac flow patterns change immediately following LAL, supporting the role of hemodynamics in the progression of HLHS. Sites of reduced WSS revealed by computational modeling are commonly affected in HLHS, suggesting that changes in the biomechanical environment may lead to abnormal growth and remodeling of left heart structures. Developmental Dynamics 243:652–662, 2014. © 2013 Wiley Periodicals, Inc.  相似文献   
995.
Large three‐dimensional cell aggregates and psammoma bodies are usually encountered in benign serous effusions (mesothelial hyperplasia and endosalpingiosis), mesotheliomas, and metastatic papillary carcinomas. We report a case of pulmonary small‐cell carcinoma occurring in an 88‐year‐old woman that initially presented with a malignant pleural effusion characterized cytologically by a predominance of large three‐dimensional neoplastic cell aggregates (“cannonballs”), associated with rare psammoma bodies. Although the crowded three‐dimensional tumor‐cell aggregates did not allow detailed cytologic examination, the diagnosis of metastatic small‐cell carcinoma could be established noting the characteristic chromatin features of the occasional single neoplastic cells and the characteristic “cell‐in‐cell” and “stack‐of‐coins” arrangements of rare small clusters of neoplastic cells. Immunoperoxidase stains showing positivity of the tumor cells for CD56, synaptophysin, and TTF1 further supported this diagnosis. Endobronchial ultrasound‐guided fine‐needle aspiration of a mediastinal lymph node subsequently confirmed the diagnosis of pulmonary small‐cell carcinoma. Metastatic pulmonary small‐cell carcinoma should be considered in the differential diagnosis of serous effusions showing large three‐dimensional neoplastic cell aggregates and psammoma bodies to prevent a potential diagnostic pitfall. Diagn. Cytopathol. 2013. © 2011 Wiley Periodicals, Inc.  相似文献   
996.
Background: Dental biofilms contain a protein that inhibits mammalian cell growth, possibly lysine decarboxylase from Eikenella corrodens. This enzyme decarboxylates lysine, an essential amino acid for dentally attached cell turnover in gingival sulci. Lysine depletion may stop this turnover, impairing the barrier to bacterial compounds. The aims of this study are to determine biofilm lysine and cadaverine contents before oral hygiene restriction (OHR) and their association with plaque index (PI) and gingival crevicular fluid (GCF) after OHR for 1 week. Methods: Laser‐induced fluorescence after capillary electrophoresis was used to determine lysine and cadaverine contents in dental biofilm, tongue biofilm, and saliva before OHR and in dental biofilm after OHR. Results: Before OHR, lysine and cadaverine contents of dental biofilm were similar and 10‐fold greater than in saliva or tongue biofilm. After 1 week of OHR, the biofilm content of cadaverine increased and that of lysine decreased, consistent with greater biofilm lysine decarboxylase activity. Regression indicated that PI and GCF exudation were positively related to biofilm lysine after OHR, unless biofilm lysine exceeded the minimal blood plasma content, in which case PI was further increased but GCF exudation was reduced. Conclusions: After OHR, lysine decarboxylase activity seems to determine biofilm lysine content and biofilm accumulation. When biofilm lysine exceeds minimal blood plasma content after OHR, less GCF appeared despite more biofilm. Lysine appears important for biofilm accumulation and the epithelial barrier to bacterial proinflammatory agents. Inhibiting lysine decarboxylase may retard the increased GCF exudation required for microbial development and gingivitis.  相似文献   
997.
Background: Chronic periodontitis (CP) and rheumatoid arthritis (RA) appear to share many pathologic features. Oxygen metabolism has an important role in the pathogenesis of both CP and RA. The aim of this study is to evaluate the relationship between these two chronic inflammatory diseases with regard to antioxidant and oxidant status. Methods: A total of 80 participants were divided into four groups of 20 each: group RA–CP (patients with RA and CP), group RA (periodontally healthy patients with RA), group CP (systemically healthy patients with CP), and group C (periodontally and systemically healthy volunteers) were included in the study. After assessment of periodontal measurements, gingival crevicular fluid (GCF) samples were taken at one incisor, premolar, and molar tooth and stored with serum samples at ?80°C for the antioxidant/oxidant assay. Results: Although all clinical measurements in groups RA–CP and CP were statistically higher compared to those of C and RA groups (P <0.001), there were no differences between CP and RA–CP groups (P >0.05). GCF total oxidant status (TOS) values of CP and RA–CP groups were higher than those of the RA group (P <0.05). GCF oxidative stress index (OSI) values of the RA–CP group were higher than those of the RA group (P <0.05). There were no differences among the groups in terms of serum TOS and OSI values (P >0.05). Conclusions: Local OSI values in groups with patients with CP were higher, whereas systemic OSI values showed no difference among the groups. The presence of RA seems not to affect local and systemic OSI values in patients with CP.  相似文献   
998.
Kido J, Bando M, Hiroshima Y, Iwasaka H, Yamada K, Ohgami N, Nambu T, Kataoka M, Yamamoto T, Shinohara Y, Sagawa I, Nagata T. Analysis of proteins in human gingival crevicular fluid by mass spectrometry. J Periodont Res 2012; 47: 488–499. © 2012 John Wiley & Sons A/S Background and Objective: Gingival crevicular fluid is a bodily fluid transuded from periodontal tissues into the gingival crevice and periodontal pocket, and contains many species of components. Proteins in gingival crevicular fluid have been studied as markers for periodontal diseases. Mass spectrometric analysis is used for the analyses of proteins, lipids, saccharides and metals, and expected as an approach for disease diagnosis. For better analysis of the protein components in gingival crevicular fluid, we investigated proteins in gingival crevicular fluid samples from the healthy gingival crevice and periodontal pocket using mass spectrometry. Material and Methods: Gingival crevicular fluid samples were collected from subjects who gave their informed consent and were periodontally healthy or had diseased pockets. These samples were electrophoretically separated, and each fraction on the gels was analysed by nano liquid chromatography coupled with tandem mass spectrometry. Antimicrobial peptides detected in gingival crevicular fluid were confirmed by western blotting. Results: One hundred and four proteins were detected in gingival crevicular fluid samples from both healthy sites and sites of periodontitis; 64 proteins were contained only in gingival crevicular fluid from healthy sites and 63 proteins were observed only in gingival crevicular fluid from periodontitis sites. These proteins were blood‐, cytoskeleton‐, immunity‐, inflammation‐ and lipid‐related proteins and enzymes. Some proteins, including ceruloplasmin, glycogen phosphorylase, glutathione S‐transferase, phosphoglycerate mutase, psoriasin, S100A11 and resistin, were identified for the first time in gingival crevicular fluid. Antimicrobial peptides, such as lactoferrin, α1‐antitrypsin, lipocalin, S100A7, S100A8, S100A9 and cathelicidin, were observed by mass spectrometry and western blotting. Conclusion: Multiple protein components in gingival crevicular fluid were analysed at the same time using mass spectrometry, and this approach may be useful for the diagnosis of periodontal diseases.  相似文献   
999.
Toker H, Akp?nar A, Ayd?n H, Poyraz O. Influence of smoking on interleukin‐1beta level, oxidant status and antioxidant status in gingival crevicular fluid from chronic periodontitis patients before and after periodontal treatment. J Periodont Res 2012; 47: 572–577. © 2012 John Wiley & Sons A/S Background and Objective: The aim of this study was to evaluate the impact of smoking on the relationship between interleukin‐1 (IL‐1β) and oxidation in patients with periodontitis and response to nonsurgical periodontal therapy. Material and Methods: Data were obtained from 30 patients with generalized chronic periodontitis (15 smokers and 15 nonsmokers) and from 10 periodontally healthy controls. IL‐1β level, total oxidant status (TOS) and total antioxidant status (TAS) were recorded in gingival crevicular fluid. Probing depth, clinical attachment level, gingival and plaque indices and bleeding on probing were also measured. The gingival crevicular fluid and clinical parameters were recorded at baseline and 6 wk after periodontal treatment. Results: The study showed statistically significant improvement of clinical parameters in both smokers and nonsmokers after periodontal treatment. Moreover, the baseline IL‐1β levels were significantly higher in smokers compared with nonsmokers (p < 0.05). After periodontal treatment, the IL‐1β levels were significantly reduced in both smokers and nonsmokers (p < 0.05). There were no significant differences in TOS and TAS between periodontitis patients and healthy controls at baseline and 6 wk after periodontal treatment. The level of IL‐1β in gingival crevicular fluid was positively correlated with TOS in both smokers and nonsmokers. Conclusions: Periodontal treatment improved the clinical parameters in both smokers and nonsmokers. The results confirm that periodontal therapy has an effect on IL‐1β levels in gingival crevicular fluid, but not on TOS and TAS.  相似文献   
1000.
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