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91.
Harada Y Han X Yamashita K Kawai T Eastcott JW Smith DJ Taubman MA 《Journal of periodontal research》2006,41(2):101-107
BACKGROUND AND OBJECTIVES: Host immune responses to periodontal pathogens have been considered to contribute to the alveolar bone destruction in periodontitis. However, the role of B lymphocytes in the pathogenesis of periodontal bone loss is not clear. METHODS: We examined the effect of adoptive transfer of antigen-specific B cells from rat spleens on experimental periodontal bone resorption. Donor rats were immunized intraperitoneally (i.p.) with formalin-killed Actinobacillus actinomycetemcomitans. Antigen-specific B cells were prepared from splenocytes by first binding CD43(+) cells to Petri dishes coated with anti-CD43 antibody to remove T cells, and non-binding cells were passed through a nylon wool column to deplete accessory cells. The retained cells were then collected and bound to A. actinomycetemcomitans-coated Petri dishes for enrichment of A. actinomycetemcomitans-binding B cells (AAB). A. actinomycetemcomitans non-binding B cells (ANB) and B cells from non-immunized donor rats (NIB) were also collected from these procedures. Each type of B cell was injected into a group of recipient rats that were then orally infected with live A. actinomycetemcomitans. RESULTS: At termination, the antibody levels to A. actinomycetemcomitans in serum and gingival wash fluids were significantly higher in the recipients transferred with AAB when compared to the recipients transferred with ANB or NIB. A markedly elevated number of antibody-forming cells were observed in the spleens of the recipients transferred with AAB, and these recipient rats also exhibited significantly increased bone resorption when compared to the other groups. CONCLUSIONS: It is suggested that B cells can contribute to periodontal bone resorption and that antigen-triggering of B cells is required for the bone resorption. 相似文献
92.
Elverdin JC Chiarenza AP Luchelli MA Vatta M Bianciotti LG Boyer P Vacas MI 《Archives of oral biology》2006,51(8):621-628
Protein restriction impairs the salivary flow rate and composition in human and rats. The aim of the present work was to establish the effect of low protein (casein 5%) and protein free (casein 0%) isocaloric diets on sympathetic activity and salivary evoked secretion in the submandibular gland (SMG) of the rat. After 21 days, rats fed casein 0% presented: (a) a significant shift to the left of the dose-response curves (DRC) to the autonomic agonists-norepinephrine (NE), methoxamine, isoproterenol (ISO) and methacholine; (b) increased food consumption (p<0.001); (c) decreased body (p<0.001) and SMG (p<0.001) weights maintaining SMG/body (w/w) relation; (d) enhanced submandibular alpha1-adrenoceptor number without changes in the apparent dissociation constant (Kd); (e) increased submandibular NE content (p<0.05) and phosphoinositoside hydrolysis (p<0.001); (f) decreased submandibular tyrosine hydroxylase activity (TH) (p<0.01). Casein 5% feeding increased food consumption (p<0.01) and reduced body weight (p<0.05). This protein restriction increased metacholine-evoked salivation, but it altered neither submandibular sympathetic activity nor sympathetic-induced salivary secretion as compared to the Control group (C) fed a similar diet containing 25.5% protein. Present results suggest that in the adult rat, a protein free diet during 21 days lowers SMG sympathetic and cholinergic activity leading to supersensitivity as revealed by up-regulation of alpha1-adrenergic receptor number and increased autonomic-evoked salivation. 相似文献
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94.
Protein carbonyl levels in serum and gingival crevicular fluid in patients with chronic periodontitis 总被引:1,自引:0,他引:1
OBJECTIVE: Evidence reveals the role of reactive oxygen species (ROS) in many pathologies including periodontitis. Protein carbonylation is the most widely used biomarker for oxidative damage to proteins, and reflects cellular damage induced by ROS. In this study protein carbonyl (PC) levels in serum and gingival crevicular fluid (GCF) in patients with chronic periodontitis (CP) was evaluated. MATERIALS AND METHODS: Thirty-three patients with CP and 24 healthy controls were included in the study. Following the clinical measurements and samplings, total protein levels in serum and GCF were determined by Bradford method, and serum and GCF PC levels were measured by modified Levine method. RESULTS: PC levels in serum and GCF were significantly higher in the CP group compared to the control group (p<0.05). In all subjects, serum and GCF PC levels showed statistically significant positive correlations with all clinical parameters (p<0.05). CONCLUSIONS: The results suggest that both systemic and local/periodontal protein carbonylation increase in CP compared to health and that elevated levels of PCs may be a sign of oxidative damage in periodontitis and correlate well with the periodontal status. 相似文献
95.
Yano-Higuchi K Takamatsu N He T Umeda M Ishikawa I 《Journal of clinical periodontology》2000,27(8):597-602
BACKGROUND, AIMS: This study investigated the prevalence of Bacteroides forsythus, Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans among various periodontitis patients and healthy individuals in Japan, and correlated it with clinical parameters. METHOD: Subgingival plaque samples were collected from 21 patients with adult periodontitis (AP), 8 with rapidly progressive periodontitis (RPP) and 15 healthy individuals. RESULTS: The frequency detected in culture was as follows: B. forsythus was found in 47.6% of AP sites and in 37.5% of RPP sites. P. gingivalis was identified in 64.3% of AP and 59.4% of RPP sites. A. actinomycetemcomitans was detected in 4.8% of AP and 3.1% of RPP sites. The 3 species were detected in only 2 of the healthy individuals. The proportion of B. forsythus in the total microflora in culture was 0.07% in the healthy group, 4.1% in AP and 2.4% in RPP. The proportions of P. gingivalis were 0% in the healthy group, 18.8% in AP and 16.2% in RPP. The proportion of A. actinomycetemcomitans was very low in all 3 groups. A DNA probe detected B. forsythus in 78.6% of AP and 65.6% of RPP sites, as well as P.gingivalis in 58.3% of AP and 59.4% of RPP sites. A. actinomycetemcomitans was detected in only 1.2% of AP sites. The 3 species were undetectable in the healthy group. CONCLUSIONS: The prevalence and the proportion of B. forsythus and P. gingivalis were significantly correlated with clinical parameters, suggesting that B. forsythus and P. gingivalis are closely related to AP and RPP in the Japanese population. 相似文献
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背景 成人社区获得性肺炎(CAP)合并呼吸道病毒感染与单纯CAP在临床治疗上是否存在差异尚不清楚。本研究拟从分析CAP合并呼吸道病毒感染病毒谱和临床特征与单纯CAP的差异来探讨此问题。目的 分析成人CAP合并呼吸道病毒感染患者的病毒谱特点及其临床特征。方法 选取2017年6月-2019年5月复旦大学附属上海市第五人民医院住院部收治的CAP患者223例,采集CAP患者的咽拭子,应用多重巢式反转录酶-聚合酶链式反应(nested multiplex RT-PCR)检测8种(10型)常见的呼吸道病毒。将CAP患者分为病毒阳性组和病毒阴性组,分析病毒阳性组CAP患者的临床特征。同时,采集病毒阳性、病毒阴性CAP患者及社区健康对照者的血清各24份,采用ELISA检测血清中白介素(IL)-6、IL-8、IL-10、干扰素(INF)-γ、干扰素诱导蛋白(IP)-10、肿瘤坏死因子(TNF)-α的浓度。结果 223例CAP患者中61例(27.35%)患者病毒检测阳性,其中单病毒感染58例(26.01%),多病毒感染3例。单病毒感染包括22例(9.87%)流感病毒A(Flu A)、14例(6.28%)鼻病毒(RhV)、9例(4.03%)流感病毒B(Flu B)、5例(2.24%)腺病毒(ADV)、2例(0.90%)冠状病毒(CoV)、2例(0.90%)呼吸道合胞病毒A(RSVA)、2例(0.90%)偏肺病毒(MPV)、1例(0.45%)博卡病毒(BoV)、1例(0.45%)呼吸道合胞体病毒B型(RSVB)。根据年龄分为非老年(≤65岁)组和老年(>65岁)组,两组病毒检出率比较,差异无统计学意义(P>0.05)。CAP患者四季均会有病毒感染,冬季为高发季节,感染病毒主要有Flu A、RhV、Flu B。按照呼吸道病毒检测结果分为病毒阳性组和阴性组,病毒阳性组死亡率高于阴性组,差异有统计学意义(P<0.05),其中病毒阳性组死亡患者均为合并流感病毒感染。进一步将呼吸道病毒阳性组分为流感组(包括Flu A和Flu B)和非流感组,发现流感组乳酸脱氢酶水平高于非流感组,流感组死亡率高于病毒阴性组(P<0.05)。影像学特征分析结果显示,病毒阳性组双肺病变、多肺叶病变、斑片状渗出影比例高于病毒阴性组,差异均有统计学意义(P<0.05)。血清细胞因子水平分析结果显示,病毒阳性组IL-10水平高于病毒阴性组。结论 上海闵行地区CAP患者合并呼吸道病毒感染较为常见,检出病毒以Flu A、RhV和Flu B为主,其临床特征无明显差异,合并流感病毒感染可能会导致死亡率增加,病毒阳性患者影像学多表现为双肺病变、多肺叶病变、斑片状渗出影,病毒阳性患者IL-10血清浓度明显升高,以上结果对于CAP合并呼吸道病毒感染有一定的参考价值。 相似文献
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