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1.
Helicobacter pylori is an established cause of gastric ulcers. Its role in causing recurrent aphthous stomatitis (RAS) remains controversial. Fifty-two RAS patients and 52 sex-matched controls were recruited in this case–control study. All subjects were screened for hematinic deficiencies and H. pylori. The latter was assessed quantitatively using the 14C-urea breath test. The χ2 test and Wilcoxon signed ranks test were used to compare H. pylori and hematinic indices between cases and controls, while conditional logistic regression was used to assess the associations between the occurrence of RAS and independent factors. H. pylori was positive in 56.7% of the overall sample, with no difference between RAS patients (50.8%) and controls (49.2%) (P = 0.843). The median H. pylori and haematological indices values did not show any association with ulcer diameter, number, or frequency. Interestingly, gastric hyperacidity was significantly associated with RAS, and this association was independent from tobacco smoking, alcohol drinking, and H. pylori (odds ratio 14.99, 95% confidence interval 2.47–90.95; P = 0.003). This study found no association between H. pylori and RAS. The association between RAS and gastric hyperacidity suggests that gastric refluxate, not H. pylori, has an effect on the oral mucosa that favours an ulcerative change.  相似文献   
2.
BACKGROUND: Despite plenty of research, the cause of recurrent aphthous stomatitis (RAS) remains obscure. It has been proposed that, the aetiological factors such as local trauma, smoking, vitamin deficiencies and viral infections lead to aphthae formation via final common pathway based on increased oxidative stress. The aim of this investigation was to evaluate the antioxidant enzyme superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSHPx) alterations in plasma and saliva, and in addition uric acid (UA) in saliva, in patients with RAS and healthy controls. METHODS: Thirty-two patients with RAS and 30 healthy controls were included into the study. The SOD, CAT, GSHPx and UA levels were measured in plasma and saliva in study and control groups. RESULTS: In the RAS group, although the mean SOD (P<0.001) and CAT (P<0.05) levels of plasma were lower, GSHPx (P<0.001) levels were higher than control group. The salivary concentrations of the SOD (P<0.001), CAT (P<0.05) and GSHPx (P<0.001) in RAS group were entirely opposite to plasma concentrations. UA were not significant between RAS group and controls. CONCLUSION: Since we found salivary SOD and CAT levels were high whereas plasma levels were low, it has been thought that, salivary defence mechanisms via antioxidant agents may be stimulated against to the ulcerous lesion. We consider that the organism might mobilize the antioxidant potential to the sites where they were needed. At this point, decrease of SOD and CAT levels in the plasma may be related to this shift. It is also thought that GSHPx secretion in the saliva may also be increased but the increase in its turnover may be responsible for the diminished activity.  相似文献   
3.
SOD药膜预防治疗急性放射性口腔炎的临床观察   总被引:16,自引:2,他引:14       下载免费PDF全文
目的 探讨超氧化物歧化酶 (SOD)对急性放射性口腔炎的临床价值。方法  90例首程放疗鼻咽癌病人随机分为 3组 :A组用自制的SOD药膜 ;B组用维斯克药液 ;C组不行任何治疗。所有病人均于第 2周末开始观察、用药 ,直至放疗第 6周末。结果 A组放射性口腔炎的发病率明显低于C组 (P <0 0 5 ) ;A组放射性口腔炎的有效率明显高于C组 (P <0 0 1)。结论 SOD对急性放射性口腔炎有明显预防及治疗作用。  相似文献   
4.
白芍总甙促干扰素诱生及抗病毒作用的研究   总被引:11,自引:0,他引:11  
研究白芍总甙的促干扰素诱生及抗病毒作用,结果表明;白芍总甙10 mg·L~(-1)在试管内无直接诱生干扰素(JFN)作用.可促进鸡新城疫互I系弱毒冻干疫苗诱生αIFN,其最适浓度为10 mg·L~(-1)可促进ConA诱生γIFN.当ConA为亚适剂量时,最适浓度为l~10 mg·L~(-1)当ConA为最适剂量时,其最适浓度为0.1 ~1mg·L~(-1),皆可提高IFN效价l~2倍。具有直接抗病毒作用,白芍总甙250 mg·L~(-1)能使水泡性口炎病毒效价下降2.22个对数值。  相似文献   
5.
Ahmed M  Cramer SD  Lyles DS 《Virology》2004,330(1):34-49
Because of its potent ability to induce apoptosis, vesicular stomatitis virus (VSV) is an attractive candidate as an oncolytic virus for tumor therapy. Previous studies have suggested that VSV selectively infects tumor cells due to defects in their antiviral responses making them more susceptible to VSV infection than normal cells. We tested this hypothesis in the prostate tumor system by comparing LNCaP and PC-3 prostate tumor cells to benign human prostatic epithelial cells from patient prostatectomy specimens. We compared the cell killing ability of a recombinant virus containing a wild-type (wt) M protein (rwt) and an isogenic M protein mutant virus (rM51R-M) that induces interferon (IFN) in infected cells and should display a greater selectivity for tumor cells. Our results showed that in single-cycle infection experiments, LNCaP cells were sensitive to killing by both wt and mutant viruses, while PC-3 cells were highly resistant to VSV-induced cell killing. LNCaP and benign prostate cells were similarly susceptible to both viruses, indicating that normal prostate cells are not inherently resistant to killing by VSV. In each of the cell lines, the rM51R-M virus induced similar levels of apoptosis to rwt virus, showing that the M protein does not play a significant role in apoptosis induction by VSV in these cells. In multiple-cycle infection experiments, LNCaP cells were more sensitive than benign prostatic epithelial cells to virus-induced cell killing by rM51R-M virus, but not rwt virus. Both viruses were equally effective at reducing LNCaP tumor volume in vivo following intratumoral and intravenous inoculation in nude mice, while PC-3 tumors were resistant to VSV treatment. None of the mice treated with rM51R-M virus died as a result of virus infection, while 50-71% of mice treated with rwt virus succumbed to virus infection. Similarly, when inoculated by the more sensitive intranasal route, the rM51R-M virus was less pathogenic than the rwt virus from which it was derived. These results indicate that M protein mutant viruses are superior candidates as oncolytic viruses for therapies of prostate tumors, but future strategies for use of VSV will require testing individual tumors for their susceptibility to virus infection.  相似文献   
6.
复发性口腔溃疡与血清TNF-α,TGF-β浓度关系的临床研究   总被引:2,自引:0,他引:2  
目的 :研究复发性口腔溃疡与血清TNF α,TGF β浓度关系。方法 :选择复发性口腔溃疡患者 3 2例 ,采用ELISA检测其血清TNF α ,TGF β水平 ,并与正常成年人作对照。结果 :复发性口腔溃疡患者TNF α水平较正常组明显升高 (P <0 .0 1) ,TGF β水平与正常组相比 ,无显著统计学差异 (P >0 .0 5 )。结论 :复发性口腔溃疡的致病过程与细胞因子TNF α有关 ,与TGF β关系不密切  相似文献   
7.
Introduction: we performed a systematic review and meta-analysis of mucocutaneous toxicities associatedwith sunitinib, an oral multi-tyrosine kinase inhibitor. Methods: eligible studies included randomized Phase II and III trials of patients with solid tumors on sunitinib daily, describing events of hand–foot syndrome, skin rash, stomatitis, and skin and hair discoloration. Results: the relative risk (RR) of all-grade hand–foot skin reaction, skin rash, stomatitis, skin and hair discoloration were 2.12 (95% CI: 1.28–3.51; p < 0.004), 1.33 (95% CI: 1.15–1.54; p < 0.0002), 1.88 (95% CI: 1.36–2.59; p = 0.0001), 16.6 (95% CI: 4.18–64.94 p < 0.003), 4.42 (95% CI: 0.8–24.5; p < 0.09); respectively. Conclusions: our meta-analysis has demonstrated that sunitinib is associated with a higher risk of developing all-grade hand–foot skin reaction, skin rash, stomatitis and skin discoloration compared with control. Clinicians should be aware of these risks and perform regular clinical monitoring.  相似文献   
8.
Helicobacter pylori(H.pylori)has been found in the oral cavity and stomach,and its infection is one of the most frequent worldwide.We reviewed the literature and conducted a Topic Highlight,which identified studies reporting an association between H.pylori-infection in the oral cavity and H.pylori-positive stomach bacterium.This work was designed to determine whether H.pylori is the etiologic agent in periodontal disease,recurrent aphthous stomatitis(RAS),squamous cell carcinoma,burning and halitosis.Record selection focused on the highest quality studies and meta-analyses.We selected 48 articles reporting on the association between saliva and plaque and H.pylori-infection.In order to assess periodontal disease data,we included 12 clinical trials and 1 meta-analysis.We evaluated 13 published articles that addressed the potential association with RAS,and 6 with squamous cell carcinoma.Fourteen publications focused on our questions on burning and halitosis.There is a close relation between H.pylori infection in the oral cavity and the stomach.The mouth is the first extra-gastric reservoir.Regarding the role of H.pylori in the etiology of squamous cell carcinoma,no evidence is still available.  相似文献   
9.
Intranasal application of vesicular stomatitis virus (VSV) produces a well-characterized model of viral encephalitis in mice. Within one day post-infection (PI), VSV travels to the olfactory bulb and, over the course of 7 days, it infects regions and tracts extending into the brainstem followed by clearance and recovery in most mice by PI day 14 (PI 14). Infectious diseases are commonly accompanied by excessive sleepiness; thus, sleep is considered a component of the acute phase response to infection. In this project, we studied the relationship between sleep and VSV infection using C57BL/6 (B6) and BALB/c mice. Mice were implanted with transmitters for recording EEG, activity and temperature by telemetry. After uninterrupted baseline recordings were collected for 2 days, each animal was infected intranasally with a single low dose of VSV (5 × 104 PFU). Sleep was recorded for 15 consecutive days and analyzed on PI 0, 1, 3, 5, 7, 10, and 14. Compared to baseline, amounts of non-rapid eye movement sleep (NREM) were increased in B6 mice during the dark period of PI 1–5, whereas rapid eye movement sleep (REM) was significantly reduced during the light periods of PI 0–14. In contrast, BALB/c mice showed significantly fewer changes in NREM and REM. These data demonstrate sleep architecture is differentially altered in these mouse strains and suggests that, in B6 mice, VSV can alter sleep before virus progresses into brain regions that control sleep.  相似文献   
10.
Noma (cancrum oris) is a destructive necrotising disease affecting orofacial tissues predominantly of malnourished young children. It is characterised by a rapid acute onset which usually starts in the mouth, spreads intra‐orally destroying soft tissue and bone and progresses to perforate the facial skin, causing disfigurement. Polybacterial anaerobic infection is critical too, but is not alone sufficient for the initiation of noma. Cofactors, first and foremost malnutrition, but also systemic viral and bacterial infections are crucial to the development of noma. A patient with necrotising stomatitis or noma must be admitted to hospital for antibiotic treatment, fluid and electrolytes as well as nutritional supplementation and general supportive treatment. The epidemiology of noma in the South African population is unknown, and the clinicopathological features are poorly characterised. Although worldwide there is no evidence that HIV infection is a strong risk factor for noma, HIV infection may play a substantial role in the pathogenesis of noma in South Africa.  相似文献   
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