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Mice immunized with two different cryptococcal antigen preparations, one a soluble culture filtrate antigen (CneF) in complete Freund’s adjuvant (CFA) and the other heat-killed Cryptococcus neoformans cells (HKC), develop two different profiles of activated T cells. CneF-CFA induces CD4+ T cells responsible for delayed-type hypersensitivity (DTH) reactivity and for amplification of the anticryptococcal DTH response, whereas HKC induce CD4+ and CD8+ T cells involved in anticryptococcal DTH reactivity and activated T cells which directly kill C. neoformans cells. The main purpose of this study was to assess the level of protection afforded by each of the two different T-cell profiles against challenge with viable C. neoformans cells, thereby identifying which activated T-cell profile provides better protection. CBA/J mice immunized with CneF-CFA had significantly better protective responses, based on better clearance of C. neoformans from tissues, on longer survival times, and on fewer and smaller lesions in the brain, than HKC-immunized mice or control mice similarly infected with C. neoformans. Both immunization protocols induced an anticryptococcal DTH response, but neither induced serum antibodies to glucuronoxylmannan, so the protection observed in the CneF-CFA immunized mice was due to the activated T-cell profile induced by that protocol. HKC-immunized mice, which displayed no greater protection than controls, did not have the amplifier cells. Based on our findings, we propose that the protective anticryptococcal T cells are the CD4+ T cells which have been shown to be responsible for DTH reactivity and/or the CD4+ T cells which amplify the DTH response and which have been previously shown to produce high levels of gamma interferon and interleukin 2. Our results imply that there are protective and nonprotective cell-mediated immune responses and highlight the complexity of the immune response to C. neoformans antigens.  相似文献   
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This study investigated the impact of the administration of HAART and anti-Koch's, singly and in combination, on sexual competence and birth statistics. Adult male Wistar rats were randomised into distilled water-treated control, HAART-treated, anti-Koch's-treated and HAART + anti-Koch's-treated groups. The 56-day oral treatment led to impaired sexual competence evident by significantly reduced motivation to mate, prolonged latencies of mount, intromissions, ejaculations and post-ejaculatory interval, as well as reduced frequencies of mount, intromissions and ejaculations. This was accompanied by significant reductions in penile erection reflex and penile grooming. HAART and anti-Koch's, when administered singly or in combination, also led to significant reductions in the circulatory follicle-stimulating hormone, luteinizing hormone, testosterone and intratesticular testosterone, but a significant rise in prolactin. Also, HAART and/or anti-Koch's significantly reduced sperm count, sperm motility, sperm viability and spermatozoa with normal morphology. Furthermore, HAART and anti-Koch's, separately or in combination, significantly lowered fertility capacity, litter size and litter weight and offspring survival. The deleterious effects of these drugs were more pronounced when combined. Findings of the present study revealed that HAART and/or anti-Koch's impair sexual competence via a testosterone-dependent hyperprolactinemia-mediated mechanism. These events are associated with reduced fertility capacity, poor sperm quality and lowered offspring survival.  相似文献   
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This study aims to synthesize and characterize an economical and ecological adsorbent with high adsorption capacity. For this purpose, the peanut shells (Pistacia vera L.) were modified chemically. After the synthesis of activated carbon (AC), the optimum conditions for enrichment steps were performed using parameters: pH and contact time for uranium in the model solutions. The measurements were carried out by inductively coupled plasma-mass spectrometry (ICP-MS). From the shapes of the BET isotherms, the AC obtained exhibits type I. The study indicated that the surface area and total pore volume of the AC were found to be 679.9 m2 g−1 and 0.31 cc g−1, respectively. The adsorption capacity was found to be 260 mg g−1. The optimum pH was found to be 6.0 for enrichment using the AC obtained by sulfuric acid as a chemical-modifier. The optimized method was applied to enrichment of U at ppb levels in the model solutions.

  相似文献   
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New amides from Zanthoxylum lemairie pericarps   总被引:1,自引:0,他引:1  
Two new aromatic amides were isolated from the pericarps of Zanthoxylum lemairie. The structures were elucidated by spectroscopic methods and confirmed by synthesis. A known aromatic amide, zanthosinamide, and four dibenzylbutyrol-actone lignans were isolated.  相似文献   
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Background

Seneca Valley virus (SVV-001) is a nonpathogenic oncolytic virus that can be systemically administered and can pass through the blood–brain barrier. We examined its therapeutic efficacy and the mechanism of tumor cell infection in pediatric malignant gliomas.

Methods

In vitro antitumor activities were examined in primary cultures, preformed neurospheres, and self-renewing glioma cells derived from 6 patient tumor orthotopic xenograft mouse models (1 anaplastic astrocytoma and 5 GBM). In vivo therapeutic efficacy was examined by systemic treatment of preformed xenografts in 3 permissive and 2 resistant models. The functional role of sialic acid in mediating SVV-001 infection was investigated using neuraminidase and lectins that cleave or competitively bind to linkage-specific sialic acids.

Results

SVV-001 at a multiplicity of infection of 0.5 to 25 replicated in and effectively killed primary cultures, preformed neurospheres, and self-renewing stemlike single glioma cells derived from 4 of the 6 glioma models in vitro. A single i.v. injection of SVV-001 (5 × 1012 viral particles/kg) led to the infection of orthotopic xenografts without harming normal mouse brain cells, resulting in significantly prolonged survival in all 3 permissive and 1 resistant mouse models (P < .05). Treatment with neuraminidase and competitive binding using lectins specific for α2,3-linked and/or α2,6-linked sialic acid significantly suppressed SVV-001 infectivity (P < .01).

Conclusion

SVV-001 possesses strong antitumor activity against pediatric malignant gliomas and utilizes α2,3-linked and α2,6-linked sialic acids as mediators of tumor cell infection. Our findings support the consideration of SVV-001 for clinical trials in children with malignant glioma.  相似文献   
9.
目的 探讨三硝基甲苯(TNT)作业工人晶体损害与尿2,6-二硝基-4-氨基甲苯(DNAT)含量的关系。方法 作业工人散瞳后检查眼晶体,并且测定班后尿DNAT含量。结果 当作业工人晶体出现混浊时,尿中DNAT含量明显增加(2.38mg/L),其与接触TNT尚未出现晶体混浊组(1.44mg/L)比较,差异有显著性(P<0.05)。结论 晶体混浊程度随尿DNAT含量的增高呈增加的趋势。ILO提出的DNAT30mg/L生物阈限值不适合我国职业人群。  相似文献   
10.

Purpose

To investigate the factors affecting primary bladder closure in cloacal exstrophy (CE). A successful primary closure is important for optimizing reconstructive outcomes, and it is a critical first-step in the reconstruction of CE. The authors' hypothesize that a smaller diastasis and use of an osteotomy are independent predictors of a successful closure.

Methods

A prospectively maintained database of 1332 exstrophy-epispadias complex (EEC) patients was reviewed for CE patients closed between 1975 and 2015. Univariate and multivariable analyses were performed to identify significant factors associated with CE primary bladder closure.

Results

Of 143?CE patients identified, 99 patients met inclusion criteria. Median follow-up time was 8.82 [IQR 5.43–14.26] years. In the multivariable model, the odds of having a successful closure are about 4 times greater for the staged cloacal approach compared to the 1-stage approach (OR, 3.7; 95% CI 1.2–11.5; p-value?=?0.023). Also, having an osteotomy increases the chance of a successful closure by almost six-fold (OR, 5.8; 95% CI 1.7–19.6; p-value?=?0.004).

Conclusions

Using the staged approach with a pelvic osteotomy is paramount to a successful primary closure in CE. The authors strongly recommend using the staged approach and osteotomy as these factors independently increase the chance for a successful primary bladder closure.

Study Type

Therapeutic study.

Level of Evidence

Level III, Retrospective comparative study.  相似文献   
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