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961.
Victor EG Zanette F Aguiar MR Aguiar CS Cardoso DC Cristiano MP Streck EL Paula MM 《Chemico-biological interactions》2007,170(1):59-66
In this article, we report the effects of acute administration of ruthenium complexes, trans-[RuCl(2)(nic)(4)] (nic=3-pyridinecarboxylic acid) 180.7 micromol/kg (complex I), trans-[RuCl(2)(i-nic)(4)] (i-nic=4-pyridinecarboxylic acid) 13.6 micromol/kg (complex II), trans-[RuCl(2)(dinic)(4)] (dinic=3,5-pyridinedicarboxylic acid) 180.7 micromol/kg (complex III) and trans-[RuCl(2)(i-dinic)(4)]Cl (i-dinic=3,4-pyridinedicarboxylic acid) 180.7 micromol/kg (complex IV) on succinate dehydrogenase (SDH) and cytochrome oxidase (COX) activities in brain (hippocampus, striatum and cerebral cortex), heart, skeletal muscle, liver and kidney of rats. Our results showed that complex I inhibited SDH activity in hippocampus, cerebral cortex, heart and liver; and inhibited COX in heart and kidney. Complex II inhibited SDH in heart and hippocampus; COX was inhibited in hippocampus, heart, liver and kidney. SDH activity was inhibited by complex III in heart, muscle, liver and kidney. However, COX activity was increased in hippocampus, striatum, cerebral cortex and kidney. Complex IV inhibited SDH activity in muscle and liver; COX activity was inhibited in kidney and increased in hippocampus, striatum and cerebral cortex. In a general manner, the complexes tested in this work decrease the activities of SDH and COX in heart, skeletal muscle, liver and kidney. In brain, complexes I and II were shown to be inhibitors and complexes III and IV activators of these enzymes. In vitro studies showed that the ruthenium complexes III and IV did not alter COX activity in kidney, but activated the enzyme in hippocampus, striatum and cerebral cortex, suggesting that these complexes present a direct action on COX in brain. 相似文献
962.
For many plants, sex is not fixed by genotype but determined by environmental conditions during development. In homosporous pteridophytes, sex is environmentally determined by the presence or absence of antheridiogens, maleness-inducing pheromones. It has been proposed that antheridiogens primarily reduce growth rate, with small gametophyte size responsible for maleness. To test this hypothesis, the effects of antheridiogen and intergametophytic competition on gender expression and gametophyte size were studied in a culture experiment with Woodwardia radicans. We found that (1) antheridiogen inhibited growth of gametophytes; and (2) slow growth favored maleness, whereas fast growth favored femaleness, irrespective of the presence or absence of antheridiogen. Both conclusions are consistent with the hypothesis that, in W. radicans, antheridiogen effect is mediated by size. They also agree with the "size-advantage" hypothesis in which energetic limitations associated with relatively small individual size impose a less severe limitation for male reproductive success than for female reproductive success. The results are also discussed with regard to a genetic sex-determining pathway that has recently been identified. 相似文献
963.
Velásquez JG Canovas S Barajas P Marcos J Jiménez-Movilla M Gallego RG Ballesta J Avilés M Coy P 《Molecular reproduction and development》2007,74(5):617-628
Sperm binding activity has been detected in zona pellucida (ZP) glycoproteins and it is generally accepted that this activity resides in the carbohydrate moieties. In the present study we aim to identify some of the specific carbohydrate molecules involved in the bovine sperm-ZP interaction. We performed sperm binding competition assays, in vitro fecundation (IVF) in combination with different lectins, antibodies and neuraminidase digestion, and chemical and cytochemical analysis of the bovine ZP. Both MAA lectin recognising alpha-2,3-linked sialic acid and neuraminidase from Salmonella typhimurium with catalytic activity for alpha-2,3-linked sialic acid, demonstrated a high inhibitory effect on the sperm-ZP binding and oocyte penetration. These results suggest that bovine sperm-ZP binding is mediated by alpha-2,3-linked sialic acid. Experiments with trisaccharides (sialyllactose, 3'-sialyllactosamine and 6'-sialyllactosamine) and glycoproteins (fetuin and asialofetuin) corroborated this and suggest that at least the sequence Neu5Ac(alpha2-3)Gal(beta1-4)GlcNAc is involved in the sperm-ZP interaction. Moreover, these results indicate the presence of a sperm plasma membrane specific protein for the sialic acid. Chemical analysis revealed that bovine ZP glycoproteins contain mainly Neu5Ac (84.5%) and Neu5GC (15.5%). These two types of sialic acid residues are probably linked to Galbeta1,4GlcNAc and GalNAc by alpha-2,3- and alpha-2,6-linkages, respectively, as demonstrated by lectin cytochemical analysis. The use of a neuraminidase inhibitor resulted in an increased number of spermatozoa bound to the ZP and penetrating the oocyte. From this last result we hypothesize that a neuraminidase from cortical granules would probably participate in the block to polyspermy by removing sialic acid from the ZP. 相似文献
964.
Dborah Geada Rodolfo Valds Arturo Escobar Dulce M. Ares Edel Torres Reinaldo Blanco Williams Ferro Dayamí Dorta Marcos Gonzlez María R. Alemn Sigifredo Padilla Leonardo Gmez Norma del Castillo Otto Mendoza Dioslaida Urquiza Yordanka Soria Jos Brito Alberto Leyva Carlos Borroto Jorge V. Gavilondo 《Biologicals》2007,35(4):309-315
Antibodies have been one of the proteins widely expressed in tobacco plants for pharmaceutical purposes, which demand contaminant free preparations. Rubisco constitutes 40-60% of tobacco leaf soluble proteins; therefore it is the major potential protein contaminant of plantibodies, while mycotoxins are toxic compounds that could be introduced during the biomass production and post-harvest stages with important consequences to human health. The objective of this paper was to investigate whether Rubisco and mycotoxins are present in Plantibody HB-01 preparations used in the immunopurification of the hepatitis B surface antigen. Rubisco was purified from Nicotiana tabacum yielding 154 microg of protein per gram of leaves and purity over 95%. Among mouse monoclonal antibodies generated against this enzyme, the CBSS.Rub-2 was selected for its immunodetection. It recognizes a conserved sequential epitope of Rubisco large subunit with an affinity constant of 0.13 x 10(8)M(-1). Rubisco quantification limit was 1 microg spreading to the measurement of this contaminant less than 4% of plantibodies samples. Additionally, according to a Reverse Phase-HPLC used to measure the level of adventitiously introduced contaminants, it can be concluded that aflatoxins B1, B2, G1 and G2 were undetected in the purified Plantibody HB-01 samples. 相似文献
965.
David Cícera Edna Barbosa Lucas Aline Maria Brito Cunha Pedro Lourenzo Oliveira Viana Yuana Ivia Ponte Yoshinaga Marcos Yukio Miyamoto Sayuri Filho Adriano Brito Chaves Varela Anna Lídia Nunes Kowaltowski Alicia Juliana Facundo Heberty Tarso 《Journal of physiology and biochemistry》2022,78(1):283-294
Journal of Physiology and Biochemistry - Typically, healthy cardiac tissue utilizes more fat than any other organ. Cardiac hypertrophy induces a metabolic shift leading to a preferential... 相似文献
966.
Iara Oliveira Costa Priscila Barreto de Jesus Tiana da Silva de Jesus Poline dos Santos Souza Paulo Antunes Horta Jos Marcos de Castro Nunes 《Journal of phycology》2019,55(6):1370-1385
The Southwest Atlantic is notable for having extensive reef areas cemented by nongeniculate coralline red algae. Based on an analysis of four genetic markers and morpho‐anatomical features, we clarify the species of Harveylithon in the tropical and warm temperate Southwest Atlantic. Species delimitation methods (mBGD, ABGD, SPN, and PTP), using three markers (psbA, rbcL, and COI), support the recognition of three new species: H. catarinense sp. nov., H. maris‐bahiensis sp. nov., and H. riosmenum sp. nov., previously incorrectly called Hydrolithon samoënse. Our findings highlight the importance of using an approach with several lines of evidence to solve the taxonomic status of the cryptic species. 相似文献
967.
Mariela Gonzlez María E. García Alberto Slanis Ana Bonini Stephanie Fiedler Laura Faria Eduardo Dellacassa Concetta Condurso Daniel Lorenzo Marcos Russo María L. Tereschuk 《化学与生物多样性》2019,16(5)
Propolis samples from north‐west Argentina (Amaicha del Valle, Tucumán) were evaluated by palynology, FT‐IR spectra, and RP‐HPTLC. In addition, the volatile fraction was studied by HS‐SPME‐GC/MS. The botanical species most visited by Apis mellifera L. near the apiaries were collected and their RP‐HPTLC extracts profiles were compared with propolis samples. In addition, GC/MS was performed for volatile compounds from Zuccagnia punctata Cav. (Fabaceae). FT‐IR spectra and RP‐HPTLC fingerprints of propolis samples showed similar profiles. In RP‐HPTLC analyses, only Z. punctata presented a similar fingerprint to Amaicha propolis. The major volatile compounds present in both were trans‐linalool oxide (furanoid), 6‐camphenone, linalool, trans‐pinocarveol, p‐cymen‐8‐ol, and 2,3,6‐trimethylbenzaldehyde. Potential variations for the Amaicha del Valle propolis volatile fraction as consequence of propolis sample preparation were demonstrated. 相似文献
968.
Peña-Moreno Irina Charlot Castro Parente Denise da Silva Jackeline Maria Andrade Mendonça Allyson Rojas Lino Angel Valcarcel de Morais Junior Marcos Antonio de Barros Pita Will 《Journal of industrial microbiology & biotechnology》2019,46(2):209-220
Journal of Industrial Microbiology & Biotechnology - In the past few years, the yeast Dekkera bruxellensis has gained much of attention among the so-called non-conventional yeasts for its... 相似文献
969.
Carole Henry Nai-Ying Zheng Min Huang Alexandra Cabanov Karla Thatcher Rojas Kaval Kaur Sarah F. Andrews Anna-Karin E. Palm Yao-Qing Chen Yang Li Katerina Hoskova Henry A. Utset Marcos C. Vieira Jens Wrammert Rafi Ahmed Jeanne Holden-Wiltse David J. Topham John J. Treanor Patrick C. Wilson 《Cell host & microbe》2019,25(3):357-366.e6
970.