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11.
Matta SG Caldas-Bussiere MC Viana KS Faes MR Paes de Carvalho CS Dias BL Quirino CR 《Animal reproduction science》2009,111(2-4):189-201
The aim of the present study was to investigate the effects of inhibition of the enzyme inducible nitric oxide synthase (iNOS) by aminoguanidine (AG) on the in vitro maturation of oocyte-cumulus cell complex(es) (COC) of cattle. COC were cultured with different concentrations of AG (0, 1, 10, and 100mM) for 24h. In Experiment 1, the extent of cumulus complex expansion, nuclear maturation status and plasma membrane integrity of oocytes and cumulus cells from each treatment were assessed. Nitrate/nitrite (NO(3)(-)/NO(2)(-)) concentrations were determined in culture medium by the Griess method. Addition of different concentrations of AG to maturation medium promoted a dose-response inhibitory effect on cumulus expansion (P<0.05). Addition of 1 and 10mM AG to IVM medium did not affect plasma membrane integrity of oocytes or nuclear maturation rates (P>0.05), but it did reduce plasma membrane integrity in cumulus cells. One hundred millimolar inhibited pre-metaphase I (pre-MI) to metaphase II (MII) transition, promoted plasma membrane damage in oocytes (P<0.05), and increased NO(3)(-)/NO(2)(-) concentration when compared to controls (P<0.05). To evaluate if this effect was reversible, 10(-5)M sodium nitroprusside (SNP, NO donor) was added, only in the treatment with 100mM AG that inhibited the nuclear maturation. However, association of 10(-5)M SNP to 100mM AG did not reverse the effects of AG, but increased NO(3)(-)/NO(2)(-)concentration (P<0.05). In Experiment 2, the effect of different AG concentrations on cytoplasmic maturation in vitro was assessed based on cortical granule migration, and embryonic development. There was a dose effect on cortical granule migration rate, in which 1mM AG (83.9+/-6.2%) did not differ from control oocytes (83.6+/-8.2%; P>0.05), but 10mM partially inhibited migration (3.8+/-6.4%) and 100mM totally inhibited migration (P<0.05). SNP (10(-5)M) did not revert this inhibitory effect on cortical granules migration in oocytes treated with 100mM AG. Only those concentrations that did not inhibit IVM were used to assess cleavage and blastocyst development. Addition of 10mM AG to IVM medium reduced (73.0+/-8.1%, 15.0+/-8.9%; P<0.05) cleavage and blastocyst development, respectively when compared with controls (89.1+/-3.4%, 37.6+/-7.3%, respectively), but did not differ, (P>0.05), from the group treated with 1mM AG (80.9+/-8.4%, 41.5+/-10.5%, respectively). The results from the present study demonstrate that NO derived from iNOS affects the in vitro maturation of bovine COC, modulating the viability of cumulus cells and of oocyte, the progression of meiosis after GVBD, the migration of cortical granules, and cleavage and blastocyst development. 相似文献
12.
We describe the design, construction, and operating characteristics of a doubly resonant cylindrical microwave cavity. This cavity has been developed to allow a search for nonlinear RF energy conversion in biological cells. Cells with a diode-like nonlinearity could demodulate a modulated RF carrier wave and generate low frequency signals in an exposed biological preparation. The cavity is designed to be resonant on the TE(111) mode at about 890 MHz and on the TE(113) mode at about 1780 MHz. The cavity performs exactly as designed and has proved capable of detecting the nonlinearity in a microscopic Schottky diode test structure. The sensitivity is sufficient to detect any nonlinearity in a collection of biological cells that could have any potential biological significance. 相似文献
13.
Di Salvatore M Orlandi A Bagalà C Quirino M Cassano A Astone A Barone C 《Cell proliferation》2011,44(2):139-146
Objectives: Although emerging data suggest that zoledronic acid (Zol) may have different anti‐tumour activities against a broad range of cancers, its effects on lung cancer remain largely unknown. The aim of this study was to evaluate in vitro the anti‐tumoural and anti‐angiogenetic effect of zoledronic acid in non‐small‐cell lung cancer (NSCLC) cells. Material and methods: We treated A549 NSCLC cells with zoledronic acid to investigate survival, cell cycle activity, anti‐angiogenic activity and apoptotic responses to it. Results: We observed that highest Zol concentration (100 μm ) caused arrest in G1 phase of the cell cycle and also induced different percentages of apoptosis in presence (0.9% versus 4.4%) or absence (2.4% versus 28.5%) of serum (P = 0.0001). Zol concentration from 5 to 100 μm for 2 days induced significant concentration‐dependent cell death in adherent cells. Furthermore, Zol (10–100 μm ) induced dose‐dependent reduction both of mRNA and protein expression of VEGF associated with parallel decrease in VEGF secretion in the culture medium. Conclusion: Taken together, these results support a possible anti‐cancer and anti‐angiogenetic activity of Zol. Our data may not only provide a basis for the clinical use of this drug as preventive agent of bone metastases but also suggest that Zol deserves attention as an anti‐cancer agent in non‐small‐cell lung cancer. 相似文献
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Mixed model methodology under univariate and bivariate animal models was used to estimate genetic parameters of scrotal circumference (SC) unadjusted (h2U) and adjusted (h2A) for body weight, from field data on 875 Nellore males sired by 80 bulls. The models included random effect of animal, the fixed effects of age of dam, year of birth, and month and year of measurement, and the covariate age of the animal. In addition, one of the models also included the covariate body weight. Using univariate models, SC estimates of h2U were 0.18, 0.65, 0.77 and 0.60, and of h2A they were 0.15, 0.60, 0.71 and 0.50, at 9, 12, 18 and 24 m.o. of age, respectively. Bivariate estimates of heritability ranged from 0.18 to 0.77 for h2U, and from 0.13 to 0.70 for h2A. The results suggest that it would be better to consider unadjusted SC rather than adjusted SC in selection programs. Bivariate body weight estimates of heritability ranged from 0.15 to 0.45. Genetic correlations between SC and body weight ranged from 0.58 to 0.71 when body weight was not included in the model, and from 0.33 to 0.64 when body weight was included. These results suggest that simultaneous selection for body weight and SC is possible in Nellore cattle. 相似文献
16.
Xóchttl Castañeda Víctor Ortíz Betania Allen Cecilia García Mauricio Hernández-Avila 《Culture, medicine and psychiatry》1996,20(2):229-247
The central topic of the article is the divided world of female commercial sex workers (FCSW) in Mexico City. Fourteen focus group sessions were conducted with 133 FCSW from varying socio-economic levels and types of work site, as well as seven individual interviews.FCSW live in a constant double bind, as mother and prostitute, and come into daily contact with society's double standard for women. Reactions include justifying sex work as a better paying employment opportunity for women, as a necessary evil, and as a type of social service, while at the same time hiding their profession from their families. FCSW also live out an archetypal female ambivalence, their selves divided between the mother/saint and the traitor/prostitute.This article defines elements which should be taken into account in culturally appropriate programs for prevention of HIV/AIDS transmission, especially the importance which FCSW give to their role as mothers and promotion of the condom as a physical and symbolic barrier between professional and private life. 相似文献
17.
Rita de Cássia Alves Nunes Fernando Yamamoto Chiba Amanda Gomes Pereira Renato Felipe Pereira Maria Sara de Lima Coutinho Mattera Edilson Ervolino Mário Jefferson Quirino Louzada Marília Afonso Rabelo Buzalaf Cristina Antoniali Silva Doris Hissako Sumida 《Biological trace element research》2016,173(1):144-153
18.
Felipe L. Assis Gabriel M. F. Almeida Danilo B. Oliveira Ana P. M. Franco-Luiz Rafael K. Campos Maria I. M. Guedes Flávio G. Fonseca Giliane S. Trindade Betania P. Drumond Erna G. Kroon J?natas S. Abrah?o 《PloS one》2012,7(11)
Since 1999, several Vaccinia virus (VACV) isolates, the etiological agents of bovine vaccinia (BV), have been frequently isolated and characterized with various biological and molecular methods. The results from these approaches have grouped these VACV isolates into two different clusters. This dichotomy has elicited debates surrounding the origin of the Brazilian VACV and its epidemiological significance. To ascertain vital information to settle these debates, we and other research groups have made efforts to identify molecular markers to discriminate VACV from other viruses of the genus Orthopoxvirus (OPV) and other VACV-BR groups. In this way, some genes have been identified as useful markers to discriminate between the VACV-BR groups. However, new markers are needed to infer ancestry and to correlate each sample or group with its unique epidemiological and biological features. The aims of this work were to characterize a new VACV isolate (VACV DMTV-2005) molecularly and biologically using conserved and non-conserved gene analyses for phylogenetic inference and to search for new genes that would elucidate the VACV-BR dichotomy. The VACV DMTV-2005 isolate reported in this study is biologically and phylogenetically clustered with other strains of Group 1 VACV-BR, the most prevalent VACV group that was isolated during the bovine vaccinia outbreaks in Brazil. Sequence analysis of C23L, the gene that encodes for the CC-chemokine-binding protein, revealed a ten-nucleotide deletion, which is a new Group 1 Brazilian VACV genetic marker. This deletion in the C23L open reading frame produces a premature stop-codon that is shared by all Group 1 VACV-BR strains and may also reflect the VACV-BR dichotomy; the deletion can also be considered to be a putative genetic marker for non-virulent Brazilian VACV isolates and may be used for the detection and molecular characterization of new isolates. 相似文献
19.
Quirino Marília Gonçalves Macedo Luciana Conci Pagnano Katia Borgia Barbosa Pagliarini-e-Silva Sarah Sell Ana Maria Visentainer Jeane Eliete Laguila 《Molecular biology reports》2021,48(6):4995-5001
Molecular Biology Reports - Toll-like receptors (TLRs) are a family of transmembrane receptors whose signaling control cellular processes of cell proliferation, survival, apoptosis, angiogenesis,... 相似文献
20.
Betania Paiva Drumond Adriano Mondini Diane J. Schmidt Roberta Vieira de Morais Bronzoni Irene Bosch Maurício Lacerda Nogueira 《PloS one》2013,8(3)
The American/Asian genotype of Dengue virus type 2 (DENV-2) was introduced into the Americas in the 80′s. Although there is no data showing when this genotype was first introduced into Brazil, it was first detected in Brazil in 1990. After which the virus spread throughout the country and major epidemics occurred in 1998, 2007/08 and 2010. In this study we sequenced 12 DENV-2 genomes obtained from serum samples of patients with dengue fever residing in São José do Rio Preto, São Paulo (SJRP/SP), Brazil, in 2008. The whole open reading frame or envelope sequences were used to perform phylogenetic, phylogeographic and evolutionary analyses. Isolates from SJRP/SP were grouped within one lineage (BR3) close to isolates from Rio de Janeiro, Brazil. Isolates from SJRP were probably introduced there at least in 2007, prior to its detection in the 2008 outbreak. DENV-2 circulation in Brazil is characterized by the introduction, displacement and circulation of three well-defined lineages in different times, most probably from the Caribbean. Thirty-seven unique amino acid substitutions were observed among the lineages, including seven amino acid differences in domains I to III of the envelope protein. Moreover, we dated here, for the first time, the introduction of American/Asian genotype into Brazil (lineage BR1) to 1988/89, followed by the introduction of lineages BR2 (1998–2000) and BR3 (2003–05). Our results show a delay between the introduction and detection of DENV-2 lineages in Brazil, reinforcing the importance and need for surveillance programs to detect and trace the evolution of these viruses. Additionally, Brazilian DENV-2 differed in genetic diversity, date of introduction and geographic origin and distribution in Brazil, and these are important factors for the evolution, dynamics and control of dengue. 相似文献