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961.
This work analyzed the histopathology and epidermal Langerhans cells (LC) of Montenegro skin test (MST) in patients with American tegumentary leishmaniasis (ATL) in order to in situ characterize and compare the immunological reaction of the two major clinical forms of ATL, localized cutaneous leishmaniasis (LCL) and mucocutaneous leishmaniasis (MCL). MST histopathology of both LCL and MCL showed superficial and deep perivascular inflammatory infiltrate composed mainly of lymphocytes and histiocytes. Epidermal LC population was higher in MST biopsies taken from LCL patients when compared to MCL group, at 48 and 72 hours after antigen inoculation. Increased number of epidermal LC displayed in MST biopsies of LCL patients represents specific cellular immunity against parasites. The decrease of LC in MST biopsies of MCL patients does not necessarily indicate a worse specific cellular immunity in this clinical form of leishmaniasis.  相似文献   
962.
Hepatitis C virus (HCV) infection remains common among hemodialysis patients and its occurrence is related mainly to nosocomial spread. Although dialysis patients with HCV infection respond well to interferon-based therapy, relapse is frequent. This study aimed at a selected group of hemodialysis patients infected with HCV infection undergoing interferon therapy who achieved end-of-treatment virological response but became HCV-RNA positive again 6 months after end-of-treatment. It was evaluated whether de novo HCV-RNA positivity in these non-sustained responders occurred due to lack of clearance of HCV after the initial response to interferon-alpha (relapse) or due to re-infection with a new strain (re-infection). Genotyping by Inno-LiPA and by phylogenetic tree analysis using partial HCV-NS5B sequences at two evaluation points: pre-treatment (T0) and 6 months after end-of-treatment (T18). Non-sustained responders (n = 15) carried subtypes 1a (8 patients), 1b (4 patients), 3a (2 patients), and 4a (1 patient) before treatment. Identical subtypes were detected in 10 patients at T18. Five patients changed genotypes at T18, suggesting nosocomial re-infection. This study emphasizes the importance of epidemiologic measures to control the re-exposure of hemodialysis patients treated previously for HCV infection.  相似文献   
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Gynecological cytology has some inaccurate morphological categorization and poor interobserver reproducibility especially for glandular lesions. Liquid-based cytology (LBC) preparations are presumed to reduce artifacts that interfere in diagnosis performance, but its value to correctly identify glandular alterations has not been sufficiently reported. The objective of this study was to compare the diagnostic performance and interobserver agreement of LBC and conventional Pap smear to identify histologically confirmed glandular lesions according to five cytologists. Sensitivity ranged from 55.8 to 73.1% and 32.7 to 48.1% for Pap smear and LBC, respectively. Specificity ranged from 66.1 to 87.1% and 69.4 to 94.4%, respectively. In general, agreement between pairs of cytologists was poor with kappa-values around 0.45. In conclusion, relying entirely on cervical cytology to rule out glandular lesions may be risky. The use of HPV DNA test alone or combined to screening glandular lesions may contribute to minimize the limitations of both conventional and LBC preparations to diagnose glandular abnormalities.  相似文献   
967.
Paradoxical sleep deprivation (PSD) produces alterations in dopaminergic systems and also modifies sexual behavior. In this work we evaluated PSD effects on the sexual response and tyrosine hydroxylase (TH) expression in dopaminergic pathways related to sexual behavior of naive and sexual experienced rats. Male Wistar rats had their sexual behavior evaluated in 6 copulatory tests, with a 4 days interval. In these tests, the animals interacted with a receptive female and parameters that compose each component of the male sexual reply (initiation, arousal and ejaculation) were evaluated. After the 5th test, the animals were randomly divided in 2 groups, control and PSD, and 96 h later they were submitted to the last copulatory test. PSD facilitated the excitatory and the ejaculatory component, increasing the copulatory efficiency. In addition, reduced mount frequency and ejaculation latency were observed. The temporal patterning of the sexual behavior was modified, with reduction in the number of mount bouts. PSD per se was not able to modify TH levels, but in PSD sexual trained rats, an increase in the number of TH-immunoreactive cellular bodies in all dopaminergic areas evaluated was detected. Our data suggest that PSD facilitates the sexual response and this facilitation combined to sexual training could be the consequence of increased TH levels in dopaminergic pathways related to sexual reply.  相似文献   
968.
OBJECTIVES: To evaluate the efficacy of a multistep cleaning method using a cleaner and a chemical disinfectant on blood-contaminated angiographic catheters and spinal needles intended to be sterilized by hydrogen peroxide gas plasma. METHOD: A mixture of radiopaque iodine contrast, bovine blood (plus ethylenediaminetetraacetic acid), and a suspension of Bacillus subtilis spores was used to simulate catheterization and needle use. The mixture was a 1:1 proportion of contrast and blood, inoculated so that there was a final concentration of B subtilis spores of 1.0x10(6) colony-forming units (CFU)/mL. The inoculated devices were cleaned using a hydrogen peroxide solution at a concentration of 1.5+/-0.5 percent by weight, followed by distilled water with enzymatic detergent. After drying, the devices were sterilized with hydrogen peroxide gas plasma. RESULTS: The initial B subtilis spore concentration inoculated into catheters and needles varied from 2.12x10(4) to 2.74x10(7) CFU/mL. The residual load of B. subtilis spores after cleaning varied from zero (no count) to a maximum of 200 CFU/device. The multistep cleaning procedure was responsible for an average 5log10 reduction of B. subtilis spores in the catheter and needle lumens. CONCLUSIONS: The hydrogen peroxide and enzymatic detergent aqueous solutions were shown to be efficacious when used as part of a multistep cleaning method. The low level of microbial contamination prior to sterilization with hydrogen peroxide gas plasma assured that the intended sterility assurance level was reached.  相似文献   
969.
Considering that mycobacterial heat-shock protein 65 (hsp65) gene transfer can elicit a profound antitumoral effect, this study aimed to establish the safety, maximum-tolerated dose (MTD) and preliminary efficacy of DNA-hsp65 immunotherapy in patients with advanced head and neck squamous cell carcinoma (HNSCC). For this purpose, 21 patients with unresectable and recurrent HNSCC were studied. Each patient received three ultrasound-guided injections at 21-day intervals of: 150, 600 or 400 microg of DNA-hsp65. Toxicity was graded according to CTCAE directions. Tumor volume was measured before and after treatment using computed tomography scan. The evaluation included tumor mass variation, delayed-type hypersensitivity response and spontaneous peripheral blood mononuclear cell proliferation before and after treatment. The MTD was 400 microg per dose. DNA-hsp65 immunotherapy was well tolerated with moderate pain, edema and infections as the most frequent adverse effects. None of the patients showed clinical or laboratory alterations compatible with autoimmune reactions. Partial response was observed in 4 out of 14 patients who completed treatment, 2 of which are still alive more than 3 years after the completion of the trial. Therefore, DNA-hsp65 immunotherapy is a feasible and safe approach at the dose of 400 microg per injection in patients with HNSCC refractory to standard treatment. Further studies in a larger number of patients are needed to confirm the efficacy of this novel strategy.  相似文献   
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