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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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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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Preparation of biochar from kaolinite and coconut husk (KCB) and further activated with HCl (KCB-A) and KOH (KCB-B) via a microwave technique for the remediation of ciprofloxacin (CIP) and tetracycline (TET) from water was carried out. Characterization using scanning electron microscopy, energy dispersive X-ray, Fourier transform infrared spectroscopy and X-ray diffraction showed the successful synthesis of functionalized biochars. Batch adsorption experiments demonstrated the potential of the adsorbents for fast and efficient removal of CIP and TET from solution. The adsorption capacities were found to be 71, 140 and 229 mg g−1 for CIP and 118, 117 and 232 mg g−1 for TET removal on KCB, KCB-A and KCB-B, respectively. For KCB, KCB-B and KCB-B, CIP adsorption best followed the pseudo second order kinetic model (PSOM), pseudo first order kinetic model (PFOM) and intraparticle diffusion (IDP) respectively. TET adsorption followed PSOM for KCB, IPD for KCB-B and PFOM for KCB-A. CIP adsorption on KCB, KCB-A and KCB-B best fit the Temkin, Langmuir and Brouers–Sotolongo isotherms, respectively, and TET adsorption on KCB best fit Brouers–Sotolongo while KCB-A and KCB-B best fit Langmuir–Freundlich. Adsorption of both contaminants was thermodynamically feasible showing that these materials are excellent adsorbents for the treatment of pharmaceuticals in water.

Preparation of biochar from kaolinite and coconut husk (KCB) and further activated with HCl (KCB-A) and KOH (KCB-B) via a microwave technique for the remediation of ciprofloxacin (CIP) and tetracycline (TET) from water was carried out.  相似文献   
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ObjectivesThe study evaluated pre and post-operative perception and aversion to caesarean delivery (CD) among men whose partners underwent the procedure.DesignA multicentre cross-sectional study.SettingTwo tertiary and two secondary health facilities.ParticipantsMen whose partners underwent CD at the study sites.MethodsParticipants were recruited by purposive sampling, data collection was through interaction via an interviewer-administered questionnaire first immediately the decision for CD was made and thereafter on the third postoperative day. Men whose partners had vaginal delivery were excluded from the study and data management was with SPSS version 21.0 while p<0.05 was significant.ResultsAwareness about CD was 84.0% mainly through the healthcare workers (42.1%) and the female partner (34.1%); 88.0% of participants recommended CD for medically-indicated reasons. The greatest influence on consent was the male partner (48.8%). The major pre-operative concerns were limitation of family size (34.7%) and fear of repeat CD (34.0%). Pre-operative perceptions of CD included being expensive (60.7%), fear of the procedure (48.0%), fear of complications (45.3%) and longer hospital stay (44.0%). Aversion to CD was 30.0% pre and 5.3% post-operation; predictors of aversion were history of previous surgery among male or female partner and awareness about CD. However, there were reductions in negative perception and aversion post-operation.ConclusionThe high negative perception and aversion to CD among male partners were reduced post-operation. Healthcare workers should address the concerns and negative perceptions about CD and prioritize patient-friendly experiences during surgical operations.FundingFunding was by the researchers; no grant or external support was received for the study.  相似文献   
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PURPOSE: To develop novel orthotopic xenograft models of medulloblastoma in severe combined immunodeficient mice and to evaluate the in vivo antitumor efficacy of valproic acid. EXPERIMENTAL DESIGN: Orthotopic xenografts were developed by injecting 10(3) to 10(5) tumor cells from four medulloblastoma cell lines (D283-MED, DAOY, MHH-MED-1, and MEB-MED-8A) into the right cerebellum of severe combined immunodeficient mice. Animals were then examined for reproducibility of tumorigenicity, cell number-survival time relationship, and histopathologic features. Tumor growth was monitored in vivo by serially sectioning the xenograft brains at 2, 4, 6, and 8 weeks postinjection. Valproic acid treatment, administered at 600 microg/h for 2 weeks via s.c. osmotic minipumps, was initiated 2 weeks after injection of 10(5) medulloblastoma cells, and treated and untreated animals were monitored for differences in survival. Changes in histone acetylation, proliferation, apoptosis, differentiation, and angiogenesis in xenografts were also evaluated. RESULTS: Tumorigenicity was maintained at 100% in D283-MED, DAOY, and MHH-MED-1 cell lines. These cerebellar xenografts displayed histologic features and immunohistochemical profiles (microtubule-associated protein 2, glial fibrillary acidic protein, and vimentin) similar to human medulloblastomas. Animal survival time was inversely correlated with injected tumor cell number. Treatment with valproic acid prolonged survival time in two (D283-MED and MHH-MED-1) of the three models and was associated with induction of histone hyperacetylation, inhibition of proliferation and angiogenesis, and enhancement of apoptosis and differentiation. CONCLUSION: We have developed intracerebellar orthotopic models that closely recapitulated the biological features of human medulloblastomas and characterized their in vivo growth characteristics. Valproic acid treatment of these xenografts showed potent in vivo anti-medulloblastoma activity. These xenograft models should facilitate the understanding of medulloblastoma pathogenesis and future preclinical evaluation of new therapies against medulloblastoma.  相似文献   
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