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1.
Summary In contrast to the situation found in two classes of warm-blooded vertebrates, mammals and birds, the class Reptilia is not uniform with regard to total genetic content; rather, it contains two distinct categories. The close cytological kinship between snakes and birds was revealed. Both are almost identical in total genetic content, which is about 50 per cent that of placental mammals. Both have microchromosomes, as well as Z-chromosomes very similar in absolute size, comprising nearly 10 per cent of the homogametic haploid (AZ) set. This leads to the implication that snakes and birds originated from the same lineage, and that their Z-chromosomes have not changed substantially since the Jurassic period of the Mesozoic era, about 180 million years ago.Within the reptilian suborder Serpentes, the step-by-step differentiation from the primitive ZW pair to the grossly heteromorphic ZW pair could be observed. In the ancient family Boidae, the sex chromosomes were still homomorphic to each other. In the family Colubridae, the beginning of heteromorphism was manifested in two ways. In some species, a pericentric inversion on the W caused it to differ from the Z; in others, duplication of the W occurred. In the family Crotalidae, the W had apparently achieved its very specialized status; it was a distinctly smaller element.In Säo Paulo, this work was supported by Fundacão de Amparo a Pesquisa do Estado de São Paulo e Fundo de Pesquisas do Instituto Butantan. In Duarte, this work was supported in part by grant CA-05138-05, National Cancer Institute, U. S. Public Health Service. Contribution No. 36-64, Department of Biology, City of Hope Medical Center. 相似文献
2.
Beatriz Pereira Moreno Gislaine Cristiane Mantovanelli Letycia Lopes Ricardo Adriano Antnio Silva Rubem Silvrio De Oliveira Emy Luiza Ishii‐Iwamoto Maria Helena Sarragiotto Debora Cristina Baldoqui 《化学与生物多样性》2020,17(3)
Studies of the phytotoxic effects between plants can be a crucial tool in the discovery of innovative compounds with herbicide potential. In this sense, we can highlight ruzigrass (Urochloa ruziziensis), which is traditionally used in the crop rotation system in order to reduce weed emergence. The aim of this work was to characterize the secondary metabolites of ruzigrass and to evaluate its phytotoxic effects. In total, eight compounds were isolated: friedelin, oleanolic acid, α‐amyrin, 1‐dehydrodiosgenone, sitosterol and stigmasterol glycosides, tricin and p‐coumaric acid. Phytotoxic effects of the crude methanolic extract and fractions of ruzigrass were assessed using germination rate, initial seedling growth, and biomass of Bidens pilosa, Euphorbia heterophylla and Ipomoea grandifolia. Chemometric analysis discriminated the weed species into three groups, and B. pilosa was the most affected by fractions of ruzigrass. The phytotoxic activities of 1‐dehydrodiosgenone, tricin, and p‐coumaric acid are also reported, and p‐coumaric acid and 1‐dehydrodiosgenone were active against B. pilosa. 相似文献
3.
Luiza Moraes Gabriel M. da Rosa Lucielen O. Santos Jorge A. V. Costa 《Biotechnology progress》2020,36(4):e2987
The present study was aimed to develop a membrane sparger (MS) integrated into a tubular photobioreactor to promote the increase of the carbon dioxide (CO2) fixation by Spirulina sp. LEB 18 cultures. The use of MS for the CO2 supply in Spirulina cultures resulted not only in the increase of DIC concentrations but also in the highest accumulated DIC concentration in the liquid medium (127.4 mg L−1 d−1). The highest values of biomass concentration (1.98 g L−1), biomass productivity (131.8 mg L−1 d−1), carbon in biomass (47.9% w w−1), CO2 fixation rate (231.6 mg L−1 d−1), and CO2 use efficiency (80.5% w w−1) by Spirulina were verified with MS, compared to the culture with conventional sparger for CO2 supply. Spirulina biomass in both culture conditions had high protein contents varying from 64.9 to 69% (w w−1). MS can be considered an innovative system for the supply of carbon for the microalgae cultivation and biomass production. Moreover, the use of membrane system might contribute to increased process efficiency with a reduced cost of biomass production. 相似文献
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Antônio B. Anderson Thiago M. J. Fiuza Gabriel S. Araujo Angela M. Canterle Luiza M. C. Canto Renato H. A. Freitas Otto B. F. Gadig Sergio R. Floeter 《Journal of fish biology》2021,99(6):2030-2034
Brazilian endemic batoid elasmobranch populations have declined dramatically in the past 40 years due to anthropic activities (e.g., overfishing). The Brazilian guitarfish, Pseudobatos horkelii, included in the IUCN red list of endangered species [Critically Endangered (CR)], has been captured as by-catch by trawling fishing boats to the edge of extinction. Despite governmental conservation initiatives, the species is still caught and commercialized along the Brazilian coast. In this study, the authors report three rare aggregation events for the Brazilian coast of P. horkelii, inside the only nearshore no-entry Brazilian marine protected area. Strategies for its protection are also discussed. 相似文献
6.
Anelise Sonza Luciana Sayuri Sanada Luiza Raulino de Oliveira Mario Bernardo-Filho Danúbia da Cunha de S-Caputo Milton Antonio Zaro Matilde Achaval 《Experimental biology and medicine (Maywood, N.J.)》2021,246(10):1210
Whole-body vibration (WBV), which is widely used as a type of exercise, involves the use of vibratory stimuli and it is used for rehabilitation and sports performance programmes. This study aimed to investigate the effect of WBV treatment in a chronic pain model after 10 WBV sessions. An animal model (chronic pain) was applied in 60 male Wistar rats (±180 g, 12 weeks old) and the animals were treated with low intensity exercise (treadmill), WBV (vibrating platform), and a combined treatment involving both. The controls on the platform were set to a frequency of 42 Hz with 2 mm peak-to-peak displacement, g ≈ 7, in a spiral mode. Before and after the vibration exposure, sensitivity was determined. Aβ-fibers-mediated mechanical sensitivity thresholds (touch-pressure) were measured using a pressure meter. C-fibers-mediated thermal perception thresholds (hot pain) were measured with a hot plate. After each session, WBV influenced the discharge of skin touch-pressure receptors, reducing mechanical sensitivity in the WBV groups (P < 0.05). Comparing the conditions “before vs. after”, thermal perception thresholds (hot pain) started to decrease significantly after the third WBV session (P < 0.05). WBV decreases mechanical hyperalgesia after all sessions and thermal sensitivity after the third session with the use of WBV. 相似文献
7.
Flávia Gerelli Ghiraldini Ana Carolina Vitolo Crispim Maria Luiza Silveira Mello 《Molecular biology of the cell》2013,24(15):2467-2476
Hyperglycemia, like aging, induces chromatin remodeling in mouse hepatocytes in comparison to normoglycemia and younger age, respectively. Changes in glucose metabolism also affect the action and expression of sirtuins, promoting changes in chromatin conformation and dynamics. Here we investigate the abundance and activity of the nuclear sirtuins Sirt1, Sirt6, and Sirt7 in mouse hepatocytes in association with specific histone acetylation, DNA damage, and the activation of nucleolar organizing regions (NORs) in hyperglycemic nonobese diabetic (NOD) and old normoglycemic BALB/c mouse strains. Higher levels of Sirt1 and PGC-1α and increased expression of gluconeogenesis pathway genes are found in the hyperglycemic NOD mice. Increased Sirt6 abundance is found in the hyperglycemic NOD mice, which might increase DNA damage repair. With aging, lower Sirt1 abundance and activity, increased acetylated histone modifications and Sirt7 levels, and NOR methylation are found. Thus, whereas in normal aging cell metabolism is reduced, in the diabetic mice a compensatory mechanism may elevate Sirt1 and Sirt6 levels, increasing gluconeogenesis and DNA repair from the oxidative damage caused by hyperglycemia. Therefore understanding the regulation of epigenetic factors in diabetes and aging is crucial for the development of new therapeutic approaches that could prevent diseases and improve quality of life. 相似文献
8.
Ana Roberta Fusco da Costa Joseph O. Falkinham III Maria Luiza Lopes Adriana Rodrigues Barretto Jo?o Soares Felicio Lúcia Helena Messias Sales Jeann Ricardo da Costa Bahia Emilyn Costa Concei??o Karla Valéria Batista Lima 《PLoS neglected tropical diseases》2013,7(7)
The majority of investigations of the epidemiology of nontuberculous mycobacteria (NTM) have focused on highly developed nations with a low prevalence of tuberculosis. In contrast, the Para state of north Brazil represents an area of high tuberculosis prevalence and increasing NTM incidence. Toward the goal of understanding the dynamics of infection by all Mycobacterium species, we report patient characteristics and the identification of NTM strains isolated from sputum samples from patients that were residents of Para, a state in the Amazon region, Northern of Brazil, over the period January 2010 through December 2011 (2 years). The 29 NTM patients comprised 13.5% of positive mycobacterial cultures over the 2-year period. A major risk factor for NTM pulmonary disease was previous tuberculosis (76%). Further, the average age of NTM patients (52 years) was significantly higher than that of tuberculosis patients (39 years) and more were female (72.4% vs. 37.4%). Unlike other Brazilian states, NTM pulmonary patients in Para were infected with a different spectrum of mycobacteria; primarily the rapidly growing Mycobacterium massiliense and Mycobacterium simiae complex. 相似文献
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10.
Alexandre Alberto Tonin Aleksandro Schafer da Silva Maria Luiza Thorstenberg Lívia Gelain Castilhos Raqueli Teresinha Fran?a Daniela Bitencourt Rosa Leal Marta Maria Medeiros Frescura Duarte Fernanda Silveira Flores Vogel Mario Luiz de La Rue Sonia Terezinha dos Anjos Lopes 《The Korean journal of parasitology》2013,51(4):421-426
Several studies have shown the mechanisms and importance of immune responses against Toxoplasma gondii infection and the notable role of cholinesterases in inflammatory reactions. However, the association between those factors has not yet been investigated. Therefore, the aim of this study was to evaluate the acetylcholinesterase (AChE) activity in blood and lymphocytes and the activity of butyrylcholinesterase (BChE) in serum of rats experimentally infected with T. gondii during the acute phase of infection. For that, an in vivo study was performed with evaluations of AChE and BChE activities on days 5 and 10 post-infection (PI). The activity of AChE in blood was increased on day 5 PI, while in lymphocytes its activity was enhanced on days 5 and 10 PI (P<0.05). No significant difference was observed between groups regarding to the activity of BChE in serum. A positive (P<0.01) correlation was observed between AChE activity and number of lymphocytes. The role of AChE as an inflammatory marker is well known in different pathologies; thus, our results lead to the hypothesis that AChE has an important role in modulation of early immune responses against T. gondii infection. 相似文献