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1.
de Sousa Sylvia Morais de Oliveira Christiane Abreu Andrade Daniele Luiz de Carvalho Chainheny Gomes Ribeiro Vitória Palhares Pastina Maria Marta Marriel Ivanildo Evódio de Paula Lana Ubiraci Gomes Gomes Eliane Aparecida 《Journal of Plant Growth Regulation》2021,40(2):867-877
Journal of Plant Growth Regulation - The rising demand for agricultural commodities in developing countries has put increasing pressure on land resources for higher yields, with associated growth... 相似文献
2.
Background
Routine antibiotic prophylaxis following snakebite is not recommended but evidence suggests that it may be common practice in Zimbabwe. This study set out to determine and describe the extent of this practice at Parirenyatwa Hospital, a large teaching hospital in Zimbabwe 相似文献3.
4.
Belline P da Melo PS Haun M Palhares FB Boer PA Gontijo JA Figueiredo JF 《Memórias do Instituto Oswaldo Cruz》2004,99(2):167-172
Angiotensin II (AII), a product of rennin-angiotensin system, exerts an important role on the function of immune system cells. In this study, the effect of AII on the phagocytic activity of mouse peritoneal macrophages was assessed. Mice peritoneal macrophages were cultured for 48 h and the influence of different concentrations of AII (10(-14) to 10(-7) M) and/or losartan, 10(-16) to 10(-6) M), an AT1 angiotensin receptor antagonist, on phagocytic activity and superoxide anion production was determined. Dimethylthiazoldiphenyltetrazolium bromide reduction and the nucleic acid content were used to assess the cvtotoxicity of losartan. A stimulatory effect on phagocytic activity (P < 0.05) was observed with 10(-13) M and 10(-12 M) AII concentrations. The addition of losartan (up to10(-14) M) to the cell cultures blocked (P < 0.001) the phagocytosis indicating the involvement of AT1 receptors. In contrast, superoxide anion production was not affected by AII or losartan. The existence of AT1 and AT2 receptors in peritoneal macrophages was demonstrated by immunofluorescence microscopy. These results support the hypothesis that AII receptors can modulate murine macrophage activity and phagocytosis, and suggest that AII may have a therapeutic role as an immunomodulatory agent in modifying the host resistance to infection. 相似文献
5.
Amino acid changes S180A (S-->A at site 180), H197Y, Y277F, T285A, and
A308S are known to shift the maximum wavelength of absorption (lambda max)
of red and green visual pigments toward blue, essentially in an additive
fashion. To test the generality of this "five-sites" rule, we have
determined the partial amino acid sequences of red and green pigments from
five mammalian orders (Artiodactyla, Carnivora, Lagomorpha, Perissodactyla,
and Rodentia). The result suggests that cat (Felis catus), dog (Canis
familiaris), and goat (Capra hircus) pigments all with AHYTA at the five
critical sites have lambda max values of approximately 530 nm, whereas rat
(Rattus norvegicus) pigment with AYYTS has a lambda max value of
approximately 510 nm, which is accurately predicted by the five-sites rule.
However, the observed lambda max values of the orthologous pigments of
European rabbit (Oryctolagus cuniculus), white-tailed deer (Odocoileus
virginianus), gray squirrel (Sciurus carolinensis), and guinea pig (Cavia
procellus) are consistently more than 10 nm higher than the predicted
values, suggesting the existence of additional molecular mechanisms for red
and green color vision. The inferred amino acid sequences of ancestral
organisms suggest that the extant mammalian red and green pigments appear
to have evolved from a single ancestral green-red hybrid pigment by
directed amino acid substitutions.
相似文献
6.
Carmen Silvia Martimbianco de Figueiredo Durval Batista Palhares Petr Melnikov Aby Jaine da Cruz Montes Moura Sandra Christo dos Santos 《Biological trace element research》2010,136(1):1-7
Zinc and copper are important trace elements in the nutrition of preterm infants. This study determined and compared the concentrations
of zinc and copper in preterm milk of mothers receiving and not receiving zinc supplementation diets. The effects of maternal
supplementation on the blood levels and anthropometric parameters were evaluated. Thirty-eight mothers and their preterm infants
were enrolled in the study. Eighteen mothers were given a daily supplementation of 50 mg zinc, whereas the other 20 were not.
Zinc and copper levels in milk were determined at 15-day intervals, as were blood zinc levels along with anthropometric parameters.
Zinc and copper contents were determined by atomic absorption spectrophotometry. No significant differences were found between
groups either for zinc values in maternal milk and infant blood or for anthropometric measurements. A pronounced decrease
in copper levels was observed in mothers receiving supplemental zinc. Zinc supplementation given to mothers who were breastfeeding
preterm infants had no significant effect on zinc secretion in milk. 相似文献
7.
B Pham Huu ChanhLasserre A Pham Huu Chanh A L Palhares de Miranda P Tronche J Couquelet C Rubat 《Prostaglandins, leukotrienes, and essential fatty acids》1988,33(2):143-147
The effects of 2-(2 dimethylaminoethyl) 5-benzylidene 6-methyl (2H,4H)-3-pyridazinone (III) were studied on the biosynthesis of TXA2 and PGI2 in vitro the TXA2 and PGI2 synthetase activity of heart tissue. Biosyntheses of TXA2 and PGI2 were carried out using arachidonic acid as a substrate and horse platelet and aorta microsomes as sources of TXA2 and PGI2 synthetases respectively. TXB2 and 6-keto PGF1 alpha were determined by RIA. III--did not significantly modify either the biosynthesis of PGI2 in vitro or the PGI2 synthetase activity of heart tissue. did not significantly inhibit TXA2 biosynthesis in vitro but markedly reduced the TXA2 synthetase activity of heart tissue: for a microsomal fraction concentration of 100 micrograms protein, the ID50 was 6.37 X 10(-5) M +/- 1.29 X 10(-8) M. Thus III behaves as a specific inhibitor of the TXA2 synthetase activity of heart tissue and could have a beneficial use in therapeutics. 相似文献
8.
Thiago?GazoniEmail author Simone?L?Gruber Ana?PZ?Silva Olivia?GS?Araújo Hideki?Narimatsu Christine?Strüssmann Célio?FB?Haddad Sanae?Kasahara 《BMC genetics》2012,13(1):109
Background
The karyotypes of Leptodactylus species usually consist of 22 bi-armed chromosomes, but morphological variations in some chromosomes and even differences in the 2n have been reported. To better understand the mechanisms responsible for these differences, eight species were analysed using classical and molecular cytogenetic techniques, including replication banding with BrdU incorporation.Results
Distinct chromosome numbers were found: 2n = 22 in Leptodactylus chaquensis, L. labyrinthicus, L. pentadactylus, L. petersii, L. podicipinus, and L. rhodomystax; 2n = 20 in Leptodactylus sp. (aff. podicipinus); and 2n = 24 in L. marmoratus. Among the species with 2n = 22, only three had the same basic karyotype. Leptodactylus pentadactylus presented multiple translocations, L. petersii displayed chromosome morphological discrepancy, and L. podicipinus had four pairs of telocentric chromosomes. Replication banding was crucial for characterising this variability and for explaining the reduced 2n in Leptodactylus sp. (aff. podicipinus). Leptodactylus marmoratus had few chromosomes with a similar banding patterns to the 2n = 22 karyotypes. The majority of the species presented a single NOR-bearing pair, which was confirmed using Ag-impregnation and FISH with an rDNA probe. In general, the NOR-bearing chromosomes corresponded to chromosome 8, but NORs were found on chromosome 3 or 4 in some species. Leptodactylus marmoratus had NORs on chromosome pairs 6 and 8. The data from C-banding, fluorochrome staining, and FISH using the telomeric probe helped in characterising the repetitive sequences. Even though hybridisation did occur on the chromosome ends, telomere-like repetitive sequences outside of the telomere region were identified. Metaphase I cells from L. pentadactylus confirmed its complex karyotype constitution because 12 chromosomes appeared as ring-shaped chain in addition to five bivalents.Conclusions
Species of Leptodactylus exhibited both major and minor karyotypic differences which were identified by classical and molecular cytogenetic techniques. Replication banding, which is a unique procedure that has been used to obtain longitudinal multiple band patterns in amphibian chromosomes, allowed us to outline the general mechanisms responsible for these karyotype differences. The findings also suggested that L. marmoratus, which was formerly included in the genus Adenomera, may have undergone great chromosomal repatterning.9.
Teixeira CP Hirsch A Perini H Young RJ 《Proceedings. Biological sciences / The Royal Society》2006,273(1589):1007-1012
We report the development of a new quantitative method of assessing the effects of anthropogenic impacts on living beings; this method allows us to assess actual impacts and to travel backwards in time to assess impacts. In this method, we have crossed data on fluctuating asymmetry (FA, a measure of environmental or genetic stress), using Didelphis albiventris as a model, with geographical information systems data relating to environmental composition. Our results show that more impacted environments resulted in statistically higher levels of FA. Our method appears to be a useful and flexible conservation tool for assessing anthropogenic impacts. 相似文献