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961.
I H Higuti L Y Murata M Stencel A De Paiva Campello A J Do Nascimento 《Cell biochemistry and function》1985,3(4):283-288
Rat liver mitochondria were stored at 0-4 degrees C for several days using an appropriate medium and energy source. The elimination of the majority of microsomes and lysosomes, that normally contaminate isolated mitochondria, had a positive effect in preservation of respiratory control, P:O ratio, and monoamine oxidase activity during long term storage. 相似文献
962.
C M Nascimento Curi M R Marmo M Egami E B Ribeiro I S Andrade M S Dolnikoff 《Biochemistry international》1991,24(5):927-935
Monosodium glutamate (MSG) has been shown to alter several neuroendocrine functions in neonatally treated rats. To evaluate possible alterations in lipogenesis rate and lipoprotein lipase (LPL) activity, male and female rats were injected during the neonatal period with MSG or saline (controls). In male MSG rats, an increase in lipogenesis of liver and retroperitoneal adipose tissues was observed. Triton WR 1339 (an LPL inhibitor) administration decreased retroperitoneal lipogenesis in these animals. In female rats, MSG-treatment increased lipogenesis only in gonadal and retroperitoneal adipose tissues. No change was observed in hepatic lipogenesis and the Triton administration did not change retroperitoneal lipogenesis. LPL activity was increased in the gonadal and retroperitoneal adipose tissues in male and female MSG-treated rats. These data suggest that there is a specific sex-dependent response in the development of MSG-induced obesity. 相似文献
963.
Fernanda N. Valentin Laura S. O. Nakaghi Srgio R. Batlouni Nivaldo F. do Nascimento Maria do Carmo Faria Paes Regiane Cristina da Silva Breno Manzini Sheryll Yohana Corchuelo Chavarro Marcelo Henrique Correa Assuno 《Zeitschrift fur angewandte Ichthyologie》2019,35(2):529-540
In the species Pseudoplatystoma fasciatum the males are smaller than females. Thus, the objective of this study was to describe the process of testicular differentiation and provide tools for sex manipulation techniques aimed at improving the productivity of farming of sexually‐reversed females. Correlation between the length, age, sex rate and the stage of gonadal development were analyzed in this species from samples collected between 0 and 240 days post‐hatching. Testicular differentiation was divided into eight stages, based on the cellular and morphological characteristics of the gonad. The results showed that sexual differentiation has a greater correlation to the size than the age in this species. This study provides knowledge on the proliferation and distinctive arrangement of somatic cells, which enabled the early identification of the testis due to the presence of future fringes in the specimens. Testicular differentiation in P. fasciatum was histologically different from other species due to the proliferation and distribution of somatic cells in the regions that would originate the testicular tubules and sperm ducts. Meiosis began at a later stage in comparison with other species, therefore, it was not considered a criterion for early sexual characterization. It can be concluded that testicular differentiation in P. fasciatum occurs relatively early and this data can be used to improve sex inversion protocols and increase productivity in this species. 相似文献
964.
965.
Marques MG Nascimento AB Gerger RP Gonçalves JS Coutinho AR Simões R Assumpção ME Visintin JA 《Zygote (Cambridge, England)》2011,19(4):331-337
This study evaluated the effects of reversible meiotic inhibition and different culture media (PZM3 or NCSU23) on production of porcine embryos by either in vitro fertilization (IVF) or parthenogenetic activation (PA). Oocytes from abattoir-derived ovaries were allocated into two groups for maturation: CHX (5 μg/ml cycloheximide for 10 h) or Control (no CHX). The percentage of metaphase II (MII) oocytes was determined at 36, 40 or 44 h of in vitro maturation. For IVF and PA, denuded oocytes were fertilized with purified sperm for 6 h or activated by electric stimuli. Zygotes were then subdivided into two culture groups: NCSU23 or PZM3. No effect of treatment with CHX and culture media was observed on cleavage (D3) and blastocyst (D7) rates in IVF and PA groups. There are no differences of quality or development rates between IVF-derived embryos cultured in NCSU23 or PZM3. However, we observed high quality PA embryos in PZM3 compared with NCSU23. Maturation arrest with CHX decreased the average blastocyst cell number in IVF while it was increased in PA embryos. As older oocytes are more effectively activated, CHX- blocked oocytes reached the mature stage faster than the control group. In conclusion, the CHX treatment for 10 h, followed by oocyte maturation for 40 h, is an efficient protocol to produce high quality parthenote embryos, especially when they are cultured in PZM3. However, this protocol is not satisfactory for IVF embryos production. In this case, a shorter maturation period could provide better embryo quality. 相似文献
966.
Juliana Cardinali-Rezende Ana M. M. Moraes Luis F. D. B. Colturato Eduardo V. Carneiro Ivanildo E. Marriel Edmar Chartone-Souza Andréa M. A. Nascimento 《World journal of microbiology & biotechnology》2011,27(2):245-252
One of the greatest challenges in contemporary society is to reduce and treat household solid waste. The choice of inoculum
to be used for start-up in reactors that degrade organic waste is critical to the success of organic waste treatment. In this
study, the functional diversity, phylogenetic identification, and biogas production of bacterial communities from six inoculum
sources were investigated. We used BIOLOG EcoPlates to evaluate the metabolic abilities of the bacterial communities, followed
16S rRNA gene sequence analysis to determine the phylogenetic affiliation of the bacteria responsible for carbon consumption.
We observed great diversity in the physiological profiles. Of the six inocula tested, the sludge from an upflow anaerobic
sludge blanket reactor (SRU) contained the most diverse, metabolically versatile microbiota and was characterized by the highest
level of biogas production. By contrast, the sludge of the anaerobic lagoon (SAL) showed the worst performance in BIOLOG EcoPlates
assays, but it exhibited the most diversity and generated the second largest amount of biogas. The bacterial isolates retrieved
from BIOLOG EcoPlates were characterized as aerobic and/or facultative anaerobic, and were mainly Gram-negative. Phylogenetic
analysis revealed that the isolates belonged to three major phyla: Proteobacteria, Firmicutes and Actinobacteria, represented
by 33 genera. Proteobacteria exhibited the most diversity. The distribution of the bacterial genera differed considerably
among the six inocula. Pseudomonas and Bacillus, which are able to degrade a wide range of proteins and carbohydrates, predominated in five of the six inocula. Analysis
of the bacterial communities in this study indicates that both SRU and SAL microbiota are candidates for start-up inocula
in anaerobic reactors. These start-up inocula must be studied further in order to identify their practical applications in
degrading organic waste. 相似文献
967.
Küppers GC Paiva Tda S Borges Bdo N Harada ML Garraza GG Mataloni G 《European journal of protistology》2011,47(2):103-123
968.
Patrícia Leal Dantas LoboCristiane Sá Roriz Fonteles Cibele Barreto Mano de CarvalhoDemétrius Fernandes do Nascimento Said Gonçalves da Cruz FonsecaFrancisco Vagnaldo Fechine Jamacaru Maria Elisabete Amaral de Moraes 《Phytomedicine》2011,18(7):551-556
Research has demonstrated the need for identifying a novel antimicrobial agent for topical use in the pediatric dental population. The essential oil of Lippia sidoides Cham. (LSO) has been described as having favorable biological properties, and a broad in vitro and in vivo antimicrobial spectrum against bacteria and yeast infections. Our aim was to determine a dose and formulation of LSO, acceptable for clinical testing in a pediatric population with dental caries. Thirty-seven 6-12-year old children were selected to participate in this study, and randomly allocated to receive different concentrations of either a gel (0.8%, 1%, 1.2% and 1.4%) or a mouth rinse (0.6%, 0.8%, 1% and 1.2%) formulation. The highest percentage MS reduction was observed with 0.8% mouth rinse and 1.4% gel. The efficacy of these concentrations was compared with a Thy-Car mixture formulated as a mouth rinse and gel treatments in 11 children. Saliva was collected after a single application of the antimicrobial treatment to establish effectiveness against MS. Both rinse (p < 0.001) and gel (p = 0.02) formulations produced significant MS reduction. Mouth rinse concentrations above 0.8% were associated with a transient intra-oral burning sensation. In conclusion, mouth rinse and gel LSO formulations demonstrated effectiveness against MS and good acceptance among children. We suggest future randomized clinical trials to test its effectiveness against early childhood caries. 相似文献
969.
970.
Oliveira Samara Rodrigues Bonfim Damasceno Franco Álvaro Xavier Quaresma Marielle Pires de Carvalho Cecília Mendes Morais da Cunha Jácome Marques Fabrícia da Silva Pantoja Patrícia Mendonça Vanessa Azevedo da Silva Osterne Vinicius José Correia Jorge Luis Almeida Assreuy Ana Maria Sampaio de Souza Marcellus Henrique Loiola Pontes do Nascimento Kyria Santiago Cavada Benildo Sousa Criddle David Neil Soares Pedro Marcos Gomes 《Glycoconjugate journal》2022,39(5):599-608
Glycoconjugate Journal - Lectins isolated from Canavalia ensiformis (ConA) and Canavalia brasiliensis (ConBr) are promising molecules to prevent cell death. Acute pancreatitis, characterized by... 相似文献