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61.
Julie Massayo Maeda Oda Karen Braj?o de Oliveira Roberta Losi Guembarovski Kalil William Alves de Lima Ana Cristina da Silva do Amaral Herrera Alda Losi Guembarovski Walter Jorge Sobrinho Daniela Rudgeri Derossi Maria Angelica Ehara Watanabe 《Molecular biology reports》2012,39(12):10131-10137
The role of chemokines and the growth factors has been extensively analyzed both in cancer risk and tumor progression. The transforming growth factor beta (TGF-β) and chemokine (C-X-C motif) receptor 4 (CXCR4) genes are implicated in several diseases, including breast cancer. Genomic DNA was obtained from 21 samples of peripheral blood or from normal tissue, previously fixed in formalin and embedded in paraffin for TGF-β T869C polymorphism analyses. Total cellular RNA was extracted from the same 21 patients, but from fresh tissue (tumor and adjacent healthy from the same breast) for expression analysis by Real Time PCR. No significant differences were observed in genotype distribution according to clinicopathological characteristics. Transforming growth factor beta (TGF-β) mRNA expression was assessed according to T869C polymorphism and CC patients presented a higher TGF-β expression but not significant when compared to other genotypes (p?=?0.064). A positive correlation was observed in relative mRNA expressions of CXCR4 and TGF-β (p?=?0.020). It is known that overexpression of TGF-β by both tumor and stromal tissue can facilitate the development of metastases, mainly by TGF-β stimulated angiogenesis and increased tumor cell motility. Our findings suggested a role of these genes as progression markers for breast carcinoma. 相似文献
62.
André Luiz Alves de Lima Everardo Valadares de Sá Barretto Sampaio Cibele Cardoso de Castro Maria Jesus Nogueira Rodal Ant?nio Celso Dantas Antonino André Laurênio de Melo 《Trees - Structure and Function》2012,26(5):1605-1616
The phenology of tree species in environments that are subject to strong climatic seasonality is mainly determined by water availability, which may vary as a function of wood density. The relationship among phenology, water potential, wood density and the capacity of water storage in the stem were determined for woody species of caatinga vegetation (dry forest) in the semiarid region of NE Brazil. Leaf flush and fall, flowering and fruiting events were recorded over a 31-month period, and the water potential was measured over a two-year period. These data were related to precipitation, water availability in the soil and photoperiod. Seven deciduous species exhibited low wood density (DLWD,?<0.5?g?cm?3), high capacity of water storage in the stem (until 250?% of the dry weight) and high water potential during the year, as opposed to 15 deciduous species that showed high wood density (DHWD,?≥0.5?g?cm?3). Leaf flush, flowering and the fruiting of DHWD species were related to precipitation, whereas these phenological events occurred at the end of the dry season and/or the beginning of the rainy season for DLWD species and were related to the photoperiod. The two evergreen species showed variations of water potential that were intermediate between those of DHWD and DLWD deciduous species, leaf flush during the dry season and flowering at the end of dry season. These results suggest the existence of three functional groups: evergreen species, DHWD deciduous species and DLWD deciduous species. 相似文献
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E S Nascimento R Figueiró J J Becnel C J P C Araújo-Coutinho 《Revista brasleira de biologia》2007,67(3):519-526
During the studies involving the correlation between the water temperature of the breeding site of Simulium pertinax larvae and the infection prevalence by microsporidia, developed in the Andorinhas river, Magé, RJ, weekly samples of blackfly larvae were taken within a two-year period (2001-2002 and 2003-2004), and it was noticed that the infections by Amblyospora sp. were more prevalent when compared to infections by Polydispyrenia sp. in larvae. It was also observed that the infections do not follow the same pattern, since the genus Amblyospora was recorded almost every month during the study with the exception of December, 2001. In the results of correlation between the environmental water temperature and the microsporidia infection rates, it was observed that for the first period studied, there was a high negative correlation, while during the second period there was absence correlation. On the other hand, the Amblyospora sp. infection rates prove that the correlation was high and significant in the first period, but was not significant in the second sampling period and Polydispyrenia sp. showed absence correlation in both periods. 相似文献
65.
Entamoeba histolytica trophozoites transfer lipophosphopeptidoglycans to enteric cell layers 总被引:3,自引:0,他引:3
Lauwaet T Oliveira MJ De Bruyne G Bruchhaus I Duchêne M Mareel M Leroy A 《International journal for parasitology》2004,34(5):549-556
Transfer of antigens frequently follows adhesion of protozoan parasites to host cells. We were interested in such transfer from the Entamoeba surface to enterocytes following adhesion of trophozoites. Therefore, cocultures of enterocytes in vitro and ex vivo with Entamoeba histolytica (strain HM-1:IMSS) or Entamoeba dispar (strain SAW760) trophozoites were processed for immunocytochemistry. The EH5 monoclonal antibody against amoebic proteophosphoglycans marked a dotted pattern on the apical side of enterocytes in in vitro cocultures with HM-1:IMSS and SAW760 trophozoites. Basolateral staining was present in cocultures following dysfunction of tight junctions, or when trophozoites made direct contact with the basolateral side of enterocytes in in vitro and ex vivo cocultures. Based on the molecular mass in Western blot, the transferred proteophosphoglycan was identified as a lipophosphopeptidoglycan. In conclusion, trophozoites transfer LPPG to the apical side of enterocytes following adhesion and prior to dysfunction of tight junctions. 相似文献
66.
Ana V. Dordio A.J. Estêvão Candeias A.P. Pinto C. Teixeira da Costa A.J. Palace Carvalho 《Ecological Engineering》2009,35(2):290-302
The aim of the present work was to evaluate the sorption capacity of light expanded clay aggregates (LECA) to remove mixtures of ibuprofen, carbamazepine and clofibric acid in water and wastewater. High removal efficiencies were attained for carbamazepine and ibuprofen while a less satisfactory performance was observed for clofibric acid. In a mixture of the three compounds in water a slight decrease in the sorbed amounts is observed in comparison with solutions of the single compounds, indicating some competitive sorption. In wastewater, the pharmaceuticals mixture also undergoes a slight reduction in the sorbed amounts of carbamazepine and ibuprofen, probably due to the presence of dissolved organic matter which increases their solubility. These compounds were removed in the following order of efficiencies in all the tested conditions: carbamazepine > ibuprofen > clofibric acid. Two other clay materials – sepiolite and vermiculite – were tested for the removal of the more recalcitrant clofibric acid, and vermiculite exhibited higher removal efficiency than LECA. The sorption is characterized by an initial fast step, with most pharmaceuticals being removed within the first 24 h. The results of this study are a first step in the process of selecting an appropriate material or combination of materials to be used as media in SSF-CWs designed for the removal of pharmaceuticals from wastewaters. 相似文献
67.
Félix TM Leistner S Giugliani R 《Birth defects research. Part A, Clinical and molecular teratology》2004,70(7):459-463
BACKGROUND: The importance of metabolic factors in neural tube defects (NTDs) has been the focus of many investigations. Several authors have suggested that abnormalities in homocysteine metabolism, such as hyperhomocysteinemia, folate deficiency, and low vitamin B12, may be responsible for these malformations and that both nutritional factors and genetic abnormalities are associated with them. METHODS: We conducted a case-control study to investigate the influence of biochemical and genetic factors in NTDs in infants in southern Brazil. Levels of folate, vitamin B12, total homocysteine (t-Hcy) and the 677C>T and 1298A>C polymorphisms of the MTHFR gene were analyzed in 41 NTD child-mother pairs and 44 normal child-mother control pairs. RESULTS: Subjects in the case group had a higher mean blood folate level than those in the control group. The level of vitamin B12 was lower in mothers in the NTD group than in control mothers (p = 0.004). The level of t-Hcy was not different in the two groups, but t-Hcy and vitamin B12 were correlated (p = 0.002). There was no difference in the genotype distribution for 677C>T and 1298A>C polymorphisms of MTHFR in the case and control pairs. The level of t-Hcy was correlated with 677TT. CONCLUSIONS: Despite the small sample in this study, we suggest that low vitamin B12 and, consequently, hyperhomocysteinemia are important risk factors for NTDs in our population. 相似文献
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Increased urine podocyte‐associated messenger RNAs in severe obesity are evidence of podocyte injury 下载免费PDF全文
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