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101.
Peruhype-Magalhães V Martins-Filho OA Prata A Silva Lde A Rabello A Teixeira-Carvalho A Figueiredo RM Guimarães-Carvalho SF Ferrari TC Correa-Oliveira R 《Scandinavian journal of immunology》2005,62(5):487-495
We investigated the cytokine profile of cells of the innate immune response and its association with active (ACT), asymptomatic (AS) and cured (CUR) human visceral leishmaniasis (VL), as well as noninfected (NI) subjects. The frequency of cytokine-producing cells was determined after short-term in vitro incubation of whole peripheral blood samples with soluble Leishmania antigen (SLA). Our data demonstrated a predominant type 2 cytokine profile in NI and ACT. In NI, we observed an increase of IL-4+ neutrophils, IL-10+ eosinophils besides a decrease of tumour necrosis factor (TNF)-alpha+ eosinophils/monocytes. Yet in ACT, we observed an increase of IL-4+ neutrophils and natural killer (NK) cells and IL-10+ monocytes, a reduced frequency of IL-12+ and IFN-gamma+ eosinophils and lower levels of TNF-alpha+ and IL-12+ monocytes. AS presented a mixed profile, characterized by an increase of IFN-gamma+ neutrophils/eosinophils and NK cells, of IL-12+ eosinophils/monocytes, as well as increase of IL-4+ neutrophils and NK cells and IL-10+ eosinophils/monocytes. In contrast, CUR was characterized by a type 1 response with an increase of IFN-gamma+ neutrophils/eosinophils and NK cells, associated with an increase in IL-12+ monocytes. In conclusion, we show a correlation between innate immune cytokine patterns and clinical status of VL, suggesting that these cells, in addition to other factors, may contribute to the cytokine microenvironment in which Leishmania-specific T cells are primed and to disease outcome. 相似文献
102.
Gaspar J.; Rodrigues A.; Laires A.; Silva F.; Costa S.; Monteiro M. J.; Monteiro C.; Rueff J. 《Mutagenesis》1994,9(5):445-449
Quercetin has been the subject of numerous studies on its genetictoxicity and carcinogenicity. Despite its well-proven geneticdamaging activity for various genetic end-points (reverse mutations,induction of SOS functions, induction of sister chromatid exchanges,chromosomal aberrations and micronuclei), the mechanisms ofgenetic damage by quercetin remain, by and large, unknown. Thepresent study aims to further extend the observations on thepossible active oxygen species mediated DNA-damaging activityof quercetin and the role of cytochrome P450-dependent metabolismon the genotoxicity of quercetin. The results reported in thiswork show that querceitn can produce the OH radical, as assessedby deoxyribose degradation in the presence of Fe3³/EDTA(ethylenediaminetetraacetic acid), and that it induces strandbreakage in isolated plasmidic DNA (pUC18). The data supportthe hypothesis that the production of OH is mediated by H2O2.The results with genetically engineered V79 cells expressingrat cytochromes 1A1, 1A2 and 2B1 failed to demonstrate metabolismof quercetin, as indicated by the fact that neither an enhancementnor a decrease in the genotoxicity of quercetin was observed.Results obtained on the pH dependence of the induction of chromosomalaberrations by quercetin in V79 cells show that, as the valueof the medium is increased to 8.0, there is a significant increasein the number of aberrant cells, as expected if oxygen radicalsare responsible for the formation of chromosomal aberrations.
3To whom correspondence should be addressed 相似文献
103.
A A Cardoso M Fallon B Mukherji M R Silva M Marusic J Gaffney J L Ascensao 《Clinical immunology and immunopathology》1992,64(2):106-111
We assayed natural killer (NK) cell activity and phenotype from human bone marrow (BM) following "purge" with 4-hydroperoxycyclophosphamide (4HC) at 60 micrograms/ml for 30 min in vitro. In all cases studied, lytic activity against the K562 cell line was either significantly decreased or abolished following 4HC purge. Although NK activity was significantly affected by 4HC treatment, no major differences in the phenotype between the purged and unpurged population were seen. Further, while in vitro culture of BM with IL2 resulted in a significant increment of NK activity, no IL-2 responsive cells were found in the 4HC purged BM after 14 days of culture. This study demonstrates that pharmacological purging of bone marrow results in a persistent functional decline of NK cell activity and may serve as a useful model for the study of the ontogeny of NK cells. 相似文献
104.
R K Rashid B Mackay E G Silva N G Ordó?ez 《Archives of pathology & laboratory medicine》1984,108(2):149-151
Primary small cell (oat cell) carcinoma of the trachea is very rare. We report a case with ultrastructural evidence of endocrine differentiation. Immunoperoxidase staining demonstrated carcinoembryonic antigen and bombesin in the tumor cells. 相似文献
105.
Norihiro Morita W.A. Saad L.A.A. Camargo C.R. Silva Neto J. Antunes-Rodrigues M.R. Covian 《Physiology & behavior》1980,24(2):243-249
Rats bearing lesions in the septal area followed by lesions in the subfornical organ were submitted to various thirst-eliciting procedures. The rats with hyperdipsia induced by lesions of the septal area drank more water than either during the control period or after lesion of the subfornical organ under the same thirst-eliciting or angiotensin-liberating stimuli (polyethyleneglycol, isoproterenol, water deprivation and ligation of the inferior vena cava). The overdrinking elicited by lesions in the septal area was blocked after lesion of the subfornical organ. Neither hypovolemia, nor hypotension or water deprivation could elicit increased water intake in animals whose subfornical organ had been destroyed. Animals with lesions in the subfornical organ showed decreased water intake after cellular dehydration. The results obtained suggest that the subfornical organ acts as a more important structure than the septal area in the regulation of water intake elicited by angiotensin, with two opposite effects: a direct one facilitating water intake, and an indirect one inhibiting the septal area. The septal area has an inhibitory effect on the subfornical organ and on water intake. 相似文献
106.
Quality of Life Research - Neck pain tends to persist for periods of 1 to 4 years of follow-up in adolescents, and a high percentage of them report disability. However, studies assessing... 相似文献
107.
Ferreira Larissa Bueno Lobo Cecília Viana do Carmo Ariene Silva Souza Rafaela Cristina Vieira e dos Santos Luana Caroline 《Maternal and child health journal》2022,26(7):1464-1472
Maternal and Child Health Journal - Dietary patterns can influence maternal and child health outcomes. The study aims to characterize dietary patterns during pregnancy as well as to identify their... 相似文献
108.
Vanessa S. Sakalidis Alethea Rea Sharon L. Perrella Jacki McEachran Grace Collis Jennifer Miraudo Stuart A. Prosser Lisa Y. Gibson Desiree Silva Donna T. Geddes 《Nutrients》2021,13(6)
During the COVID-19 pandemic, breastfeeding women have experienced restricted access to support, placing them at increased risk of mental health concerns and limited breastfeeding assistance. This study investigated the effect of the pandemic on feeding choices and maternal wellbeing amongst breastfeeding mothers living in Australian and New Zealand. We conducted a cross-sectional online survey that examined feeding methods, maternal mental wellbeing, worries, challenges, and positive experiences during the pandemic. Most women were exclusively breastfeeding (82%). Partial breastfeeding was associated with perceived low milk supply and longer pregnancy duration during the pandemic. Reduced mental health and wellbeing was associated with lower levels of family functioning, increased perceived stress, and perinatal anxiety. Longer pregnancy duration during the pandemic was associated with lower mental health wellbeing scores, while higher perceived stress scores were reported for regions with higher COVID-19 infection rates and women with perceived low milk supply. Women reported that the pandemic resulted in less pressure and more time for family bonding, while worries about the pandemic, family health, and parenting challenges were also cited. Mental health concerns of breastfeeding women appear to be exacerbated by COVID-19, highlighting a critical need for access to mental health and broader family support during the pandemic. 相似文献
109.
110.
Neves Lia Mara Grosso Tim Carla Roberta Floriano Elaine Medeiros da Silva de Avó Lucimar Retto Fernandes João Batista Parizotto Nivaldo Antonio Cominetti Marcia Regina 《Lasers in medical science》2021,36(4):863-870
Lasers in Medical Science - Ultraviolet radiation (UVR) is the major etiologic agent of cutaneous photoaging, and different strategies are used to prevent and treat this condition. The... 相似文献