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541.
Cell-mediated immunity conferred by CD4+ T helper cells is considered the predominant host defense against mucosal Candida infections, with Thelper (Th1)-type responses associated with resistance to infection and Th2-type responses associated with susceptibility to infection. Oropharyngeal candidiasis, the most common oral opportunistic infection in HIV-infected persons, is associated with a Th2-type cytokine profile in saliva. To obtain more direct evidence for a role of salivary cytokines in susceptibility to oropharyngeal candidiasis during immunosuppression, we evaluated Th1/Th2-type cytokines in the saliva of those with denture stomatitis, a form of oropharyngeal candidiasis not related to immunosuppression. Results showed that HIV-negative denture wearers with and without denture stomatitis demonstrated a mixed Th1/Th2 cytokine profile with no significant differences found between the groups. These results suggest that a local Th cytokine dichotomy in saliva is not associated with susceptibility to denture stomatitis in immunocompetent persons. 相似文献
542.
Postoperative intestinal care after major gynecologic surgery has changed considerably. The purpose of this review was to describe these changes. Our findings are that (1) preoperative mechanical bowel preparation does not lower the risk of anastomotic leakage and infection, (2) elective postoperative nasogastric tube decompression increases postoperative pneumonia and does not decrease the incidence of other postoperative complications, (3) early feeding after major gynecologic surgery reduces hospital stay and does not increase (and may decrease) pneumonia and other postoperative complications, and (4) early feeding, gum chewing, bowel stimulation, alvimopan, and ketorolac may decrease the incidence of postoperative ileus. 相似文献
543.
HPV genotypes and cervical intraepithelial neoplasia in a multiethnic cohort in the southeastern USA
Adriana C. Vidal Jennifer S. Smith Fidel Valea Rex Bentley Maggie Gradison Kimberly S. H. Yarnall Anne Ford Francine Overcash Kathy Grant Susan K. Murphy Cathrine Hoyo 《Cancer causes & control : CCC》2014,25(8):1055-1062
Purpose
For poorly understood reasons, invasive cervical cancer (ICC) incidence and mortality rates are higher in women of African descent. Oncogenic human papillomavirus (HPV) genotypes distribution may vary between European American (EA) and African-American (AA) women and may contribute to differences in ICC incidence. The current study aimed at disentangling differences in HPV distribution among AA and EA women.Methods
Five-hundred and seventy-two women were enrolled at the time of colposcopic evaluation following an abnormal liquid-based cytology screen. HPV infections were detected using HPV linear array, and chi-squared tests and linear regression models were used to compare HPV genotypes across racial/ethnic groups by CIN status.Results
Of the 572 participants, 494 (86 %) had detectable HPV; 245 (43 %) had no CIN lesion, 239 (42 %) had CIN1, and 88 (15 %) had CIN2/3. Seventy-three percent of all women were infected with multiple HPV genotypes. After adjusting for race, age, parity, income, oral contraception use, and current smoking, AAs were two times less likely to harbor HPV 16/18 (OR 0.48, 95 % CI 0.21–0.94, p = 0.03) when all women were considered. This association remained unchanged when only women with CIN2/3 lesions were examined (OR 0.22, 95 % CI 0.05–0.95, p = 0.04). The most frequent high-risk HPV genotypes detected among EAs were 16, 18, 56, 39, and 66, while HPV genotypes 33, 35, 45, 58, and 68 were the most frequent ones detected in AAs.Conclusions
Our data suggest that while HPV 16/18 are the most common genotypes among EA women with CIN, AAs may harbor different genotypes. 相似文献544.
Hernández-Sierra JF Salas-López EK Martínez-Gutiérrez F Ruíz F Pierdant-Pérez M Mandeville P Pozos-Guillén AJ 《The Journal of clinical pediatric dentistry》2010,35(2):183-185
Dental caries is a worldwide public health problem. S mutans plays an important role in the etiology of caries. There have been studies that showed the antimicrobial properties of silver nanoparticles are an effective agent to diminish S. mutans. The objective of this study was to evaluate the bactericidal and bacteriostatic effects of silver nanoparticles in addition to the Gantrez S-27 copolymer, on S mutans. METHOD: We performed an in vitro experimental study using the liquid microdilution method in order to find the minimum inhibitory concentrations (MICs) and the minimum bactericidal concentrations (MBCs) with the subcultures obtained. The mixture was obtained by preparing 98 microg/mL of silver nanoparticles (10(3)mol) with Gantrez S-27 2%, in distilled water The readings were performed 24 hours after incubation and on 3 consecutive days. The results showed an average MTC of 6.12 microg /mL and MBC of 6.12 microg /mL. CONCLUSION: The addition of Gantrez 2% to silver nanoparticles does not alter its antimicrobial effect. 相似文献
545.
Raymond Salvador Salvador Sarr Jesús J. Gomar Jordi Ortiz‐Gil Fidel Vila Antoni Capdevila Ed Bullmore Peter J. McKenna Edith Pomarol‐Clotet 《Human brain mapping》2010,31(12):2003-2014
Abnormal interactions between areas of the brain have been pointed as possible causes for schizophrenia. However, the nature of these disturbances and the anatomical location of the regions involved are still unclear. Here, we describe a method to estimate maps of net levels of connectivity in the resting brain, and we apply it to look for differential patterns of connectivity in schizophrenia. This method uses partial coherences as a basic measure of covariability, and it minimises the effect of major physiological noise. When overall (net) connectivity maps of a sample of 40 patients with schizophrenia were compared with the maps from a matched sample of 40 controls, a single area of abnormality was found. It is an area of patient hyper‐connectivity and is located frontally, in medial and orbital structures, clearly overlapping the anterior node of the default mode network (DMN). When this area is used as a region of interest in a second‐level analysis, it shows functional hyper‐connections with several cortical and subcortical structures. Interestingly, the most significant abnormality is found with the caudate, which has a bilateral pattern of abnormality, pointing to a possible DMN–striatum deviant relation in schizophrenia. However, hyper‐connectivity observed with other regions (right hippocampus and amygdala, and other cortical structures) suggests a more pervasive alteration of brain connectivity in this disease. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
546.
Denture stomatitis (DS) is a fungal infection characterized by inflammation of the oral mucosa in direct contact with the denture and affects up to 50% of denture wearers. Despite the prevalence, very little is known about the role of fungal or host factors that contribute to pathogenesis. Recently, we developed a novel intraoral denture system for rodent research. This denture system consists of custom-fitted fixed and removable parts to allow repeated sampling and longitudinal studies. The purpose of this study was to use this denture system to develop a clinically relevant animal model of DS. To establish DS, rats were inoculated with pelleted Candida albicans, which resulted in sustained colonization of the denture and palate for 8 weeks postinoculation. Biofilm formation on the denture was observed by week 4 and on the palate by week 6 postinoculation. Rats were monitored for clinical signs of disease by assigning a clinical score after macroscopic examination of the palate tissue according to Newton's method. By week 4 postinoculation, the majority of inoculated rats with dentures exhibited a clinical score of 1 (pinpoint erythema). By week 6 and week 8 postinoculation, increasing percentages of rats exhibited a clinical score of 2 (diffuse erythema/edema). Histological analysis of palate tissue demonstrated progressively increasing inflammatory cell recruitment throughout the time course of the infection. Palatal biofilm formation was commensurate with development of palatal erythema, which suggests a role for biofilm in the inflammatory response. 相似文献
547.
OBJECTIVE: In HIV+ persons with reduced CD4+ T cells, oropharyngeal candidiasis (OPC) is often associated with the accumulation of CD8+ T cells at the epithelial/lamina propria interface within the lesion together with increased tissue-associated cytokines and chemokines. Despite this reactivity, a dysfunction in the ability of the CD8+ cells to reach the organism at the outer epithelium is postulated. The purpose of this study was to examine chemokine receptors present in the OPC lesions for a potential role in susceptibility to infection. METHODS: Biopsies taken from buccal mucosa of HIV- persons, healthy mucosa of HIV+ OPC- persons, and OPC lesions were processed for protein immunohistochemical staining or RNA analysis by real-time PCR and Superarray. RESULTS: There was little change in expression of chemokine receptors at the protein or RNA level between OPC+ and OPC- tissue. At the protein level, increases occurred in OPC+ persons only if associated with CD8 cells. In the Superarray, of the 22 chemokine receptor mRNAs expressed, c. 90% remained unchanged (< 1.0-fold change) between HIV- and HIV+ tissue and between HIV+ OPC- and HIV+ OPC+ tissue. CONCLUSION: Tissue-associated chemokine receptor expression does not appear to contribute to the dysfunction in cellular migration associated with susceptibility to OPC. 相似文献
548.
Characterization of the immune status of CD8+ T cells in oral lesions of human immunodeficiency virus-infected persons with oropharyngeal Candidiasis 下载免费PDF全文
Oropharyngeal candidiasis (OPC) remains the most common oral infection in human immunodeficiency virus (HIV) disease. In a high percentage of HIV(+) persons with reduced CD4(+) T cells, oral lesions with Candida present at the outer epithelium have an accumulation of CD8(+) T cells at the epithelium-lamina propria interface associated with reduced expression of the mucosal cell-trafficking adhesion molecule E-cadherin. The purpose of the present study was to characterize the immune status of these CD8(+) T cells. Immunohistochemical staining for phenotypic and activation and costimulation markers was performed on frozen biopsy tissue sections from HIV(+) OPC(+) persons with accumulated CD8(+) T cells. CD8(+) T cells consisted primarily of central memory cells by virtue of positive CD45RO (memory) and CD27 (central memory) expression. However, concomitant negative expression of CD62L and CCR7 (effector memory) was suggestive of a transitioning memory phenotype within the tissue. Despite this, the cells are considered to be activated on the basis of positive expression of CD69. The CD8(+) T cells are not considered to be NK T cells or anti-HIV CD8(+) T cells because of negative or low expression of CD161 and vascular cell adhesion molecule, respectively. These results suggest that the accumulated mucosal migratory-challenged CD8(+) T cells are otherwise normal memory T cells in an activated state. 相似文献
549.
Acute hyperglycemia without ketosis is recognized to induce movement disorders characterized by hemichorea, hemiballismus, or hemidystonia. A video-case of hyperkinetic movement disorder resembling stereotypies in the context of uncompensated hyperglycemia without ketosis is presented, expanding the clinical phenotype of this disorder. 相似文献
550.
Baizabal-Carvallo JF Rosso C Alonso-Juarez M Pires C Samson Y 《Journal of neurology》2012,259(6):1045-1050
A rapid and complete recanalization of the occluded artery is the ideal goal when intravenous (IV) recombinant tissue plasminogen activator (rt-PA) is administrated to patients with acute ischemic stroke, i.e., limiting the ongoing ischemia to achieve a better outcome. We explored the effect of complete versus partial recanalization of the occluded intracranial artery after IV thrombolysis on the infarct growth and evaluated the functional impact. Using diffusion-weighted (DWI) volumetric measurements before rt-PA administration (DWI(1)) and 24?h later (DWI(2)), we calculated the infarct growth in 36 consecutive patients with ischemic stroke treated with IV rt-PA, with the formula DWI(2)/DWI(1). Recanalization of the affected artery was assessed by transcranial Doppler (TCD) and magnetic resonance angiography (MRA) within 24?h of stroke onset. Three patients were eliminated from the analysis; 33?patients were fully analyzed (men: n?=?23; mean (SD) age: 72.4?±?16?years; time from stroke onset to rt-PA: 179?±?54?min; mean NIHSS score at admission: 17). Patients achieving full recanalization by TCD had a smaller infarct growth, compared to those who had a partial or persistent occlusion after thrombolysis: 1.86 versus 2.91 (P?=?0.017). This difference was not significant using MRA criteria: 2.01 versus 2.69 (P?=?0.193). In the regression analysis, complete recanalization by TCD was an independent predictor of infarct growth (P?=?0.045). Thus, complete recanalization measured by TCD within 24?h of IV thrombolysis was independently associated with smaller infarct growth. 相似文献