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1.
Coelomic cavities are relatively isolated from the systemic circulation of blood cells. Resident cell populations have a proper phenotype and kinetics, maintaining their steady-state populations and their responsiveness to local inflammatory reactions, in which the number and quality of coelomic cells can be greatly increased and modified. We have addressed the question of whether the increase in cell infiltrate in the inflamed abdominal cavity is sustained by the proliferation of myeloid cells in the omentum, and if so what are the characteristics of the progenitor cells involved and how the omentum controls their proliferation and differentiation. In the omentum under normal conditions and with inflammation due to schistosomal infection we found that pluripotent early myeloid progenitors were capable of giving rise to all the myeloid lineages in clonogenic assays, but not to the totipotent blood stem cells. Besides the major haemopoietins (GM-CSF, M-CSF, G-CSF, IL-5), the omentum stroma constitutively expressed SDF-1 alpha, the chemokine which elicits homing of circulating early haemopoietic progenitors. While normal omentum stroma produced LIF, its expression was substituted by SCF in inflamed tissues. In the first situation a slow steady-state renewal of progenitors is potentially favoured, while their intense expansion may be predominant in the latter one. We propose that the increase in cells in the abdominal cavity in inflammatory reactions is due to the enhanced input and expansion of early myeloid progenitors sustaining the in situ production of abdominal cell populations, rather than to the input of systemic circulating inflammatory cells.  相似文献   
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Thirty‐seven isolates of Didymella bryoniae from three Cucurbitaceae species were collected in Brazil and tested for pathogenicity to watermelon. All isolates were pathogenic but differed in aggressiveness levels. Seven representative isolates were used in cross‐pathogenicity tests against 10 cucurbitaceous hosts. Most isolates were pathogenic to most host species tested, except to Sechium edule. Among the susceptible species, Citrullus and Cucumis species were the most susceptible hosts, while pumpkin and Luffa purgans were the most resistant. Host of origin affected the pattern of aggressiveness on each host. Isolates from watermelon were very aggressive to their original host, but much less aggressive or not pathogenic at all to some Cucurbita. Two previously described random‐amplified polymorphic DNA (RAPD)‐specific primers indicated that 81% of the isolates could be classified into the so‐called RG I group, while the remaining isolates could not be classified into any of the described RG groups. All 37 isolates were further characterized by RAPD fingerprinting and compared with three US isolates representative of RG I and RG II groups. The Brazilian D. bryoniae isolates could be separated into genetically similar clusters. The majority of the isolates were grouped in cluster DB Ia, which contained only isolates of Citrullus lanatus and Cucumis melo. Two of the American isolates used as controls clustered with this group at 68% similarity level. The DB Ib cluster included three Brazilian isolates obtained from melon and watermelon and the American representative for RG II, at a lower similarity level (43%). Two isolates from watermelon clustered with one isolate from melon in a separate group (DB II), while one single isolate from pumpkin (DB III) showed the lowest genetic similarity to all other isolates. Didymella bryoniae isolates from Brazil showed, therefore, a level of genetic diversity higher than previously reported for the species. RAPD fingerprinting allowed for geographical distinction of D. bryoniae isolates but no correlation between genetic distance, aggressiveness or origin of the isolate was found.  相似文献   
3.
An active Trypanosoma cruzi transmission cycle maintained by wild rodents in the Andean valleys of Cochabamba Bolivia is described. Wild and domestic Triatoma infestans with 60% infection with T. cruzi were found and was evidenced in 47.5% (rodents) and 26.7% (marsupial) by parasitological and/or serologycal methods. Phyllotis ocilae and the marsupial species Thylamys elegans, are the most important reservoirs followed by Bolomys lactens and Akodon boliviensis. In spite of both genotypes (TCI and TCII) being prevalent in Bolivia, in our study area only T. cruzi I is being transmitted. Our data suggest that wild T. infestans and wild small mammals play an important role in the maintenance of the transmission cycle of T. cruzi. Furthermore, the finding of high prevalence of T. cruzi infection in wild T. infestans point to the risk of the dispersion of Chagas' disease.  相似文献   
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SH-SY5Y is a human neuroblastoma cell line that can be differentiated into several neuronal phenotypes, depending on culture conditions. For this reason, this cell line has been widely used as an in vitro model of neurodegenerative conditions, such as Parkinson's disease (PD). However, most studies published to date used fetal bovine serum (FBS) as culture medium supplement for SH-SY5Y cell differentiation. We report on the testing of human platelet lysate (hPL) as a culture medium supplement to support SH-SY5Y cell culture. Both standard hPL and a fibrinogen-depleted hPL (FD-hPL) formulation, which does not require the addition of anticoagulants to culture media, promoted an increase in SH-SY5Y cell proliferation in comparison to FBS, without compromising metabolic activity. SH-SY5Y cells cultured in hPL or FD-hPL also displayed a higher number of neurite extensions and stained positive for MAP2 and synaptophysin, in the absence of differentiation stimuli; reducing hPL or FD-hPL concentration to 1% v/v did not affect cell proliferation or metabolic activity. Furthermore, following treatment with retinoic acid (RA) and further stimulation with brain-derived neurotrophic factor (BDNF) and nerve growth factor beta (NGF-β), the percentage of SH-SY5Y cells stained positive for dopaminergic neuronal differentiation markers (tyrosine hydroxylase [TH] and Dopamine Transporter [DAT]) was higher in hPL or FD-hPL than in FBS, and gene expression of dopaminergic markers TH, DAT, and DR2 was also detected.  相似文献   
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Halieutopsis bathyoreos Bradbury, 1988 (Lophiiformes: Ogcocephalidae), previously described only on the basis of the holotype (62.6mm in standard length) from the central North Pacific, is redescribed on the basis of the holotype and six additional specimens (41.2–68.7mm in standard length) collected from the western South Pacific, off Papua New Guinea, and the western North Pacific, including the Japanese Archipelago. Halieutopsis bathyoreos is distinguished from its congeners by having a shelflike rostrum extending anteriorly well beyond the mouth, a dorsal escal lobe slightly bisected ventrally, an illicial cavity square in outline and completely visible in ventral view, and lacking tubercles on the ventral surface of the disk. The following characters are newly added to the diagnoses of this species: rostrum width 21–29% of head length, tubercles on the dorsal surface of the disk about half the diameter of those on the lateral margin, and 13–15 large lateral-line scales on the tail.  相似文献   
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BackgroundIn many countries, young women of reproductive age have been especially affected by the HIV epidemic, which have fostered research to better understand how HIV infection influences and shapes women´s fertility and reproductive and sexual decisions. In Brazil, few studies have focused on the impact of the HIV epidemic on contraceptive choices among women living with HIV (WLHIV).ObjectiveThis study evaluates the impact HIV infection may have in the access to female sterilization in Brazil, using a time-to-event analysis.MethodsA cross-sectional quantitative study (GENIH study) was conducted between February 2013 and April 2014 in the city of São Paulo, comparing two probabilistic samples of 975 WLHIV and 1,003 women not living with HIV (WNLHIV) aged 18 to 49. Sexual and reproductive data was collected retrospectively in order to reconstruct women''s reproductive trajectories. Given the objectives of this study, the analysis was restricted to women with parity one or more and, in case of WLHIV, to those sterilized after HIV diagnosis and not infected through vertical transmission. The final sample analysis included 683 WNLHIV and 690 WLHIV. A series of multivariable-adjusted Cox models estimated the probability of being sterilized after HIV diagnosis, compared with WNLHIV. Models were adjusted for schooling, race/color, and stratified by parity at last delivery (1–2, 3+). Hazard ratios were calculated for female sterilization, and separately for interval and postpartum procedures (performed in conjunction with caesarean section or immediately after vaginal delivery). Additionally, information regarding unmet demand for female sterilization was also explored.FindingsNo statistical difference in the overall risk of sterilization between WLHIV and WNLHIV in the two parity-related groups is observed: HR = 0.88 (0.54–1.43) and 0.94 (0.69–1.29), respectively, among women with 1–2 children and those with three and more. However, significant differences regarding the impact of HIV infection at sterilization are observed depending on the timing and the type of sterilization procedure. The probability of obtaining an interval sterilization is significantly lower for WLHIV compared to those not living with HIV. The reverse occurs regarding postpartum sterilization. Although sterilization is mainly performed in conjunction with caesarean section in Brazil, it is evident that caesarean sections are not the sole factor increasing the risk of sterilization among WLHIV.ConclusionThe results indicate barriers in the access to services offering interval sterilization for WLHIV and certain facilitation in obtaining the procedure in conjunction with caesarean section. Health policy makers at local and national levels should promote institutional changes in order to facilitate access to interval sterilization and to confront the sensitive discussion of WLHIV’s eligibility for postpartum sterilization. It is also urgent to increase access to a wider range of contraceptive methods for WLHIV and promote dual method protection strategies. Moreover, since condom use may decrease in the future in the context of the preventive effect of antiretroviral therapy, promoting dual methods will expand the choices regarding the reproductive rights of women living with HIV.  相似文献   
9.
Philander opossum and Didelphis marsupialis considered the most ancient mammals and an evolutionary success, maintain parasitism by Trypanosoma cruzi without developing any apparent disease or important tissue lesion. In order to elucidate this well-balanced interaction, we decided to compare the humoral immune response kinetics of the two didelphids naturally and experimentally infected with T. cruzi and immunized by different schedules of parasite antigens, employing an indirect fluorescence antibody test (IFAT). Both didelphids responded with high serological titers to different immunization routes, while the earliest response occurred with the intradermic route. Serological titers of naturally infected P. opossum showed a significant individual variation, while those of D. marsupialis remained stable during the entire follow-up period. The serological titers of the experimentally infected animals varied according to the inoculated strain. Our data suggest that (1) IFAT was sensitive for follow-up of P. opossum in natural and experimental T. cruzi infections; (2) both P. opossum and D. marsupialis are able to mount an efficient humoral immune response as compared to placental mammals; (3) experimentally infected P. opossum and D. marsupialis present distinct patterns of infection, depending on the subpopulation of T. cruzi, (4) the differences observed in the humoral immune responses between P. opossum and D. marsupialis, probably, reflect distinct strategies selected by these animals during their coevolution with T. cruzi.  相似文献   
10.
    
The objective was to develop an efficient protocol for cryopreservation of agouti (Dasyprocta aguti) ovarian tissue. Agouti ovarian fragments were placed, for 10 min, in a solution containing MEM and fetal bovine serum plus 1.5 M dimethyl sulfoxide (DMSO), ethylene glycol (EG) or propanediol (PROH); some of those fragments were subsequently cryopreserved in a programmable freezer. After exposure and/or thawing, all samples were fixed in Carnoy prior to histological analysis. To evaluate ultrastructure, follicles from the control and all cryopreserved treatments were fixed in Karnovsky and processed for transmission electron microscopy. After exposure and freezing, there was a significant decrease in the percentage of morphologically normal preantral follicles in all treatments when compared to the control (92.67 ± 2.79, mean ± SD). However, there were no significant difference when the exposure and freezing procedures were compared using the same cryoprotectant. Moreover, there was no significant difference among cryoprotectants at the time of exposure (DMSO: 64.7 ± 3.8; EG: 70.7 ± 11.2, PROH: 63.3 ± 8.5) or after freezing (DMSO: 60.6 ± 3.6, EG: 64.0 ± 11.9; PROH: 62.0 ± 6.9). However, only follicles frozen with PROH had normal ultrastructure. In conclusion, preantral follicles enclosed in agouti ovarian tissue were successfully cryopreserved using 1.5 M PROH, with satisfactory maintenance of follicle morphology and ultrastructure.  相似文献   
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