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41.
Amoxicillin and clavulanic acid concentrations in gingival crevicular fluid   总被引:1,自引:0,他引:1  
Abstract The β-lactams are bactericidal antibiotics, but some of them may be inactivated by bacterial β-lactamases which destroy the β-lactam ring. The inactivation of amoxicilhn by β-Iactamases of gram negative anaerobic bacteria can be circumvented by the addition of clavulanic acid, a β-lactamases inhibitor. Thus, most of these bacteria are susceptible to this combination. The aim of this study was to investigate the concentrations of amoxicillin and clavulanic acid in gingival crevicular fluid (GCF). These concentrations were measured in 20 patients with rapidly progressive periodontitis 1 h after a dose of 500 mg (1 tablet Augmentin®) on day 0 and 1 h after the 10th intake on day 3. For the sampling of GCF, Periopapers® were introduced in 16 gingival sites per subject and time. The GCF volumes collected were estimated using the Periotron 6000®. A high performance liquid chromatography method has been developed for the determination of amoxicillin and clavulanic acid in microsamples (1 to 10 μl) of GCF. The concentrations of amoxicillin and clavulanic acid were respectively, 14.05 μg ml-1 and 0.40 μg ml-1 at day 0.13.93 μg ml-1 and 0.37 μg ml-1 at day 3. Effective levels of amoxicillin and clavulanic acid, well above the minimal inhibitory concentrations of some susceptible periodontal anaerobes (P. intermedia) involved in destructive periodontal diseases, are achieved following the multiple administration of amoxicillin combined with clavulanic acid.  相似文献   
42.
Abstract This study investigated interactions between mucosal lesions and bacterial invasion in ulcerative colitis using the acridine-orange staining method. In all 16 cases of ulcerative colitis, the mucosa was found to be invaded by small rods and cocci. In five of 10 controls, bacteria were seen only adhering to the mucosa and no bacteria were detected in the five remaining cases. It is suggested that the presence of bacteria in the colonic mucosa may be a factor responsible for the persistence or aggravation of ulcerative colitis.  相似文献   
43.
本文对77例肺癌,48例食管鳞癌和14例良性疾病病人进行了鳞癌相关抗原(SquamousCellCarinomaAntigen,SCC—Ag)测定,肺鳞癌(45例)阳性率为68.8%(>1.5ng/ml);腺癌(18例)阳性率16.6%;小细胞癌(8例)阳性率12.5%;大细胞癌(6例)阳性率16.7%。食管鳞癌阳性率31.3%。14例良性疾病均阴性。治疗前SCC—Ag浓度与肿瘤分期呈对应关系,肺鳞癌Ⅰ期阳性率为22.2%;Ⅱ期为64.2%;Ⅲ期82.3%;Ⅳ期则100%。食管鳞癌Ⅰ~Ⅱ期阳性率为13.4%;Ⅲ~Ⅳ期阳性率为48%。在行肿瘤根治切除的病人,其SCC—Ag在术后72小时内转阴,而行非根治手术的病人,其SCC—Ag仍为阳性。治疗后无转移和复发的鳞癌病人,其SCC—Ag持续阴性,该抗原在治疗后由阴性再次上升为阳性,临床均证实为复发。  相似文献   
44.
可同化有机碳(AOC)是一项新的水质检测指标,通过它可以评估供水系统的水中是否有足够的营养物质可使微生物再生长。由于目前尚无可行的化学方法检测 AOC,因此主要是用各种生物方法加以检测。本文介绍用荧光假单胞菌 P—17菌株和螺菌属 NOX 菌株作为测试菌,通过定量观察其在水样中的生长,如从接种到生长至最大数量,以考察其利用水中营养物质的情况,进而推算出水中 AOC 的浓度。  相似文献   
45.
目的观察双歧杆菌三联活菌肠溶胶囊联合阿奇霉素序贯疗法治疗对肺炎支原体肺炎腹泻患儿胃肠炎症的调节作用。 方法将肺炎支原体肺炎伴腹泻的患儿106例均分为对照组和观察组。对照组采用阿奇霉素序贯疗法治疗,观察组在对照组基础上给予双歧杆菌三联活菌肠溶胶囊治疗。比较两组疗效和肠道菌群失调发生率。比较两组胃肠激素、降钙素原(PCT)、C反应蛋白(CRP)、中性粒细胞百分比(NEUT%)、嗜酸性粒细胞计数(EOS)水平。 结果观察组总有效率高于对照组(P<0.05)。治疗后,两组胃肠激素和PCT、CRP、NEUT%、EOS较治疗前下降(P<0.05),且观察组低于对照组(P<0.05)。观察组肠道菌群失调发生率低于对照组(P<0.05)。 结论双歧杆菌三联活菌肠溶胶囊联合阿奇霉素序贯疗法治疗可减轻肺炎支原体并腹泻肺炎患儿炎症反应,调节胃肠激素,降低患儿肠道菌群失调的发生。  相似文献   
46.
The omptins are a family of enterobacterial surface proteases/adhesins that share high sequence identity and a conserved beta-barrel fold in the outer membrane. The omptins are multifunctional, and the individual omptins exhibit differing virulence-associated functions. The Pla plasminogen activator of Yersinia pestis contributes by several mechanisms to bacterial invasiveness and the systemic, uncontrolled proteolysis in plague. Pla proteolytically activates the human proenzyme plasminogen and inactivates the antiprotease alpha2-antiplasmin, and its binding to laminin localizes the uncontrolled plasmin activity onto basement membranes. These properties enhance bacterial migration through tissue barriers. Pla also degrades circulating complement proteins and functions in bacterial invasion into human epithelial cells. PgtE of Salmonella enterica and OmpT of Escherichia coli have been shown to degrade cationic antimicrobial peptides from epithelial cells or macrophages. PgtE and SopA of Shigella flexneri appear important in the intracellular phases of salmonellosis and shigellosis, whereas functions of OmpT have mainly been associated with protein degradation in E. coli cells. The differing virulence roles and functions have been attributed to minor sequence variations at the surface-exposed regions important for substrate recognition, to the dependence of omptin functions on lipopolysaccharide, and to the different regulation of omptin expression.  相似文献   
47.
Since Berger's original paper on mesangial IgA-IgG deposition with hematuria, there have been a number of clinical and pathological studies regarding IgA immune complexes, the mechanisms of glomerular IgA deposition leading to glomerular injury and animal models of IgA nephropathy. During the last quarter of this century, glomerular changes such as IgA nephropathy have also been observed in cases associated with other diseases, such as systemic lupus erythematosus, Schoenlein-Henoch purpura, liver cirrhosis and chronic inflammatory diseases of the lung. This evidence supports the idea of an IgA nephropathy syndrome. On the other hand, IgA is thought to be an important humoral factor at the mucosal immune system and appears to have an antibody function against various etiologic candidates of extrinsic or intrinsic substances at the mucosal and systemic immune system. Glomerular IgA deposition in IgA nephropathy syndrome is thought to result from elevated levels of circulating immune complexes or aggregated IgA due to an overproduction of polymeric IgA as antibodies in the serum and due to the clearance impairment of IgA immune complexes in the hepatic and splenic phagocytic system. The glomerular IgA subclass is not one-sided, but should be evaluated in comparison with the age of patients at renal biopsy; this indicates the approximate age of onset. Cirrhotic IgA glomerulonephritis is not related to Hepatitis B or C virus infection, but to the pathophysiologic condition of liver cirrhosis. Various etiologic candidates such as viral, microbial, dietary antigens or auto-antigens have been listed and experimental models of IgA nephropathy syndrome have provided some clues in understanding the etiology of primary IgA nephropathy. However much still remains to be clarified and some specific epitopes common among these etiologic candidates will have to be identified.  相似文献   
48.
Germ-free HLA-B27 transgenic (TG) rats do not develop colitis, but colonization with specific pathogen-free (SPF) bacteria induces colitis accompanied by immune activation. To study host-dependent immune responses to commensal caecal bacteria we investigated cytokine profiles in mesenteric lymph node (MLN) cells from HLA-B27 TG versus nontransgenic (non-TG) littermates after in vitro stimulation with caecal bacterial lysates (CBL). Supernatants from CBL-stimulated unseparated T- or B- cell-depleted MLN cells from HLA-B27 TG and non-TG littermates were analysed for IFN-gamma, IL-12, TNF, IL-10 and TGF-beta production. Our results show that unfractionated TG MLN cells stimulated with CBL produced more IFN-gamma, IL-12 and TNF than did non-TG MLN cells. In contrast, CBL-stimulated non-TG MLN cells produced more IL-10 and TGF-beta. T cell depletion abolished IFN-gamma and decreased IL-12 production, but did not affect IL-10 and TGF-beta production. Conversely, neither IL-10 nor TGF-beta was produced in cultures of B cell-depleted MLN. In addition, CD4(+) T cells enriched from MLN of HLA-B27 TG but not from non-TG rats produced IFN-gamma when cocultured with CBL-pulsed antigen presenting cells from non-TG rats. Interestingly, IL-10 and TGF-beta, but not IFN-gamma, IL-12 and TNF were produced by MLN cells from germ-free TG rats. These results indicate that the colitis that develops in SPF HLA-B27 TG rats is accompanied by activation of IFN-gamma-producing CD4(+) T cells that respond to commensal bacteria. However, B cell cytokine production in response to components of commensal intestinal microorganisms occurs in the absence of intestinal inflammation.  相似文献   
49.
148例新生儿眼结膜炎与产妇阴道病原感染相关性的分析   总被引:1,自引:0,他引:1  
目的了解自然分娩产妇产道细菌性感染(不包括衣原体)对于新生儿眼结膜炎的发病影响,加强围产期保健,防止婴幼儿视力损害。方法对148例新生儿眼结膜炎患者作结膜囊渗出物细菌培养和药敏试验,根据培养结果将患儿分为A组:培养阴性(无菌生长)组,B组:培养阳性组(有菌生长),同时相应将A组、B组患儿母亲分为产妇A组和产妇B组,作阴道分泌物涂片革兰染色检查相对照。结果产妇A组检出病原菌者5例(17.2%),清洁度正常,未检出病原菌及滴虫者24例(82.8%)。患儿B组检出淋病奈瑟氏菌13株(10.9%),其它各属菌株106株(89.1%)。产妇B组涂片见有白细胞内外革兰阴性双球菌者11例(9.2%);其它病原菌及念珠菌、滴虫感染者76例(63.9%),清洁度正常,未检出病原菌及滴虫者32例(26.9%)。产妇A组产道感染阳性率17.2%,B组阳性率73.1%,两者比较差异有极显著性(P〈0.001)。结论新生儿眼结膜炎与产妇产道感染有密切相关性,应加强对妊娠中晚期孕妇的生殖道感染防治,减少新生儿经产道感染的几率。  相似文献   
50.
Adoptive transfer of CD4+ T cells into scid mice leads to a chronic colitis in the recipients. The transferred CD4+ T cells accumulate in the intestinal lamina propria (LP), express an activated Th1 phenotype and proliferate vigorously when exposed ex vivo to enteric bacterial antigens. As LP CD4+ T cells from normal BALB/c mice do not respond to enteric bacterial antigens, we have investigated whether colonic LP-derived CD4+ T cells from normal mice suppress the antibacterial response of CD4+ T cells from scid mice with colitis. LP-derived CD4+ T cells cocultured with bone marrow-derived dendritic cells effectively suppress the antibacterial proliferative response of CD4+ T cells from scid mice with colitis. The majority of these LP T-reg cells display a nonactivated phenotype and suppression is independent of antigen exposure, is partly mediated by soluble factor(s) different from IL-10 and TGF-beta, and is not prevented by the addition of high doses of IL-2 to the assay culture. Functionally and phenotypically the T-reg cells of the present study differ from previously described subsets of T-reg cells. The presence of T cells with a regulatory potential in the normal colonic mucosa suggests a role for these cells in the maintenance of local immune homeostasis of the gut.  相似文献   
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