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101.
Alzamora AC Santos RA Campagnole-Santos MJ 《American journal of physiology. Regulatory, integrative and comparative physiology》2002,283(5):R1187-R1195
The objective of the present study was to determine the contribution of the autonomic nervous system and nitric oxide to the depressor effect produced by unilateral microinjection of ANG-(1-7) and ANG II into the caudal ventrolateral medulla (CVLM). Unilateral microinjection of ANG-(1-7), ANG II (40 pmol), or saline (100 nl) was made into the CVLM of male Wistar rats anesthetized with urethane before and after intravenous injection of 1) methyl-atropine, 2.5 mg/kg; 2) prazosin, 25 microg/kg; 3) the nitric oxide synthase (NOS) inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), 5 mg/kg; or 4) the specific inhibitor of neuronal NOS, 7-nitroindazole (7-NI), 45 mg/kg. Arterial pressure and heart rate (HR) were continuously monitored. Microinjection of ANG-(1-7) or ANG II into the CVLM produced a significant decrease in mean arterial pressure (MAP; -11 +/- 1 mmHg, n = 12 and -10 +/- 1 mmHg, n = 10, respectively) that was not accompanied by consistent changes in HR or in cardiac output. The effect of ANG-(1-7) was abolished after treatment with methyl-atropine (-3 +/- 0.6 mmHg, n = 9) or L-NAME (-2.3 +/- 0.5 mmHg, n = 8) or 7-NI (-2.8 +/- 0.6 mmHg, n = 5). In contrast, these treatments did not significantly interfere with the ANG II effect (-10 +/- 2.6 mmHg, n = 8; -8 +/- 1.5 mmHg, n = 8; and -12 +/- 3.6 mmHg, n = 6; respectively). Peripheral treatment with prazosin abolished the hypotensive effect of ANG-(1-7) and ANG II. Microinjection of saline did not produce any significant change in MAP or in HR. These results suggest that the hypotensive effect produced by ANG II at the CVLM depends on changes in adrenergic vascular tonus and, more importantly, the hypotensive effect produced by ANG-(1-7) also involves a nitric oxide-related mechanism. 相似文献
102.
Elgersma Y Fedorov NB Ikonen S Choi ES Elgersma M Carvalho OM Giese KP Silva AJ 《Neuron》2002,36(3):493-505
To investigate the function of the alpha calcium-calmodulin-dependent kinase II (alphaCaMKII) inhibitory autophosphorylation at threonines 305 and/or 306, we generated knockin mice that express alphaCaMKII that cannot undergo inhibitory phosphorylation. In addition, we generated mice that express the inhibited form of alphaCaMKII, which resembles the persistently phosphorylated kinase at these sites. Our data demonstrate that blocking inhibitory phosphorylation increases CaMKII in the postsynaptic density (PSD), lowers the threshold for hippocampal long-term potentiation (LTP), and results in hippocampal-dependent learning that seems more rigid and less fine-tuned. Mimicking inhibitory phosphorylation dramatically decreased the association of CaMKII with the PSD and blocked both LTP and learning. These data demonstrate that inhibitory phosphorylation has a critical role in plasticity and learning. 相似文献
103.
104.
Histological development of the long‐snouted seahorse Hippocampus guttulatus during ontogeny
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Claudia Ofelio Alcira Ofelia Díaz Giuseppe Radaelli Miquel Planas 《Journal of fish biology》2018,93(1):72-87
The objective of the present study was to describe histological development of the European long‐snouted seahorse Hippocampus guttulatus, to increase understanding of the biology and physiology of the species. Most vital organs were present in juveniles by the time of their release from the male's pouch. Digestive tract specialization occurred at 89 effective day‐degrees (D°eff), corresponding to 15 days post partum (dpp), with development of the first intestinal loop and mucosal folding. At 118 D°eff (20 dpp), lipids were being mobilized from the liver and oocytes attained the perinuclear stage. The fovea emerged at 177 D°eff (30 dpp), contemporaneous with the shift from pelagic to benthic behaviour in juveniles. At this stage, the most interesting feature was the formation of the second intestinal loop. Male gonads were never observed during the study (from 0 to 354 D°eff; 0–60 dpp), but the first oogonia were present at 30 D°eff (5 dpp). In 354 D°eff (60 dpp) juveniles, oocytes were observed in a cortical alveoli stage, indicating maturity. Low digestive efficiency was observed at early stages, which was due to a poorly developed gastrointestinal tract and an immature digestive tract prior to 89 D°eff. The present study demonstrates that approximately 89 and 177 D°eff represent two important transitional stages in the early development of H. guttulatus. At a temperature of approximately 19 ± 1°C and an age of 1 month (177 D°eff), main organs were fully functional, suggesting that the adult phenotype was largely established by that age, with females becoming mature at the age of 2 months (354 D°eff). 相似文献
105.
David Requena Ana Chumbe Michael Torres Ofelia Alzamora Manuel Ramirez Hugo Valdivia-Olarte Andres Hazaet Gutierrez Ray Izquierdo-Lara Luis Enrique Saravia Milagros Zavaleta Luis Tataje-Lavanda Ivan Best Manolo Fernández-Sánchez Eliana Icochea Mirko Zimic Manolo Fernández-Díaz 《Bioinformation》2013,9(10):528-536
Background: Avibacterium paragallinarum, the causative agent of infectious coryza, is a highly
contagious respiratory acute disease of poultry, which affects commercial chickens, laying hens and broilers worldwide.
Methodology: In this study, we performed the whole genome sequencing, assembly and annotation of a Peruvian
isolate of A. paragallinarum. Genome was sequenced in a 454 GS FLX Titanium system. De novo assembly was
performed and annotation was completed with GS De Novo Assembler 2.6 using the H. influenzae str. F3031 gene model.
Manual curation of the genome was performed with Artemis. Putative function of genes was predicted with Blast2GO.
Virulence factors were identified by comparison with the Virulence Factor Database.
Results: The genome obtained has a length of 2.47 Mb with 40.66% of GC content. Seventy five large contigs
(>500 nt) were obtained, which comprised 1,204 predicted genes. All the contigs are available in Genbank
[GenBank: PRJNA64665]. A total of 103 virulence factors, reported in the Virulence Factor Database, were
found in A. paragallinarum. Forty four of them are present in 7 species of Haemophilus, which are related
with pathogenesis, virulence and host immune system evasion. A tetracycline-resistance associated transposon
(Tn10), was found in A. paragallinarum, possibly acting as a defense mechanism.
Discussion and conclusion: The availability of A. paragallinarum genome represents an important source of information for
the development of diagnostic tests, genotyping, and novel antigens for potential vaccines against infectious coryza.
Identification of virulence factors contributes to better understanding the pathogenesis, and planning efforts for prevention
and control of the disease. 相似文献
106.
Rodrigues MC Campagnole-Santos MJ Machado RP Silva ME Rocha JL Ferreira PM Santos RA Alzamora AC 《Peptides》2007,28(7):1375-1382
In the present study, we evaluated the involvement of the rennin-angiotensin system (RAS) in the control of the blood pressure (BP), baroreceptor-mediated bradycardia and the reactivity of caudal ventrolateral medulla (CVLM) neurons to Ang II and to AT(2) receptor antagonist in sedentary or trained renovascular hypertensive rats. Physical activity did not significantly change the baseline mean arterial pressure (MAP), heart rate (HR) or the sensitivity of the baroreflex bradycardia in normotensive Sham rats. However, in 2K1C hypertensive rats, physical activity induced a significant fall in baseline MAP and HR and produced an improvement of the baroreflex function (bradycardic component). The microinjections of Ang II into the CVLM produced similar decreases in MAP in all groups, Sham and 2K1C, sedentary and trained rats. The hypotensive effect of Ang II at the CVLM was blocked by previous microinjection of the AT(2) receptors antagonist, PD123319, in all groups of rats. Unexpectedly, microinjection of PD123319 at the CVLM produced a depressor effect in 2K1C sedentary that was attenuated in 2K1C trained rats. No significant changes in MAP were observed after PD123319 in Sham rats, sedentary or trained. These data showed that low-intensity physical activity is effective in lowering blood pressure and restoring the sensitivity of the baroreflex bradycardia, however these cardiovascular effects are not accompanied by changes in the responsiveness to Ang II at CVLM in normotensive or hypertensive, 2K1C rats. In addition, the blood pressure changes observed after AT(2) blockade in 2K1C rats suggest that hypertension may trigger an imbalance of AT(1)/AT(2) receptors at the CVLM that may be restored, at least in part, by low-intensity physical activity. 相似文献
107.
Luis E. Eguiarte Ofelia A. Jiménez Barrón Erika Aguirre-Planter Enrique Scheinvar Niza Gámez Jaime Gasca-Pineda Gabriela Castellanos-Morales Alejandra Moreno-Letelier Valeria Souza 《American journal of botany》2021,108(2):216-235
With more than 200 species, the genus Agave is one of the most interesting and complex groups of plants in the world, considering for instance its great diversity and adaptations. The adaptations include the production of a single, massive inflorescence (the largest among plants) where after growing for many years, sometimes more than 30, the rosette dies shortly afterward, and the remarkable coevolution with their main pollinators, nectarivorous bats, in particular of the genus Leptonycteris. The physiological adaptations of Agave species include a photosynthetic metabolism that allows efficient use of water and a large degree of succulence, helping to store water and resources for their massive flowering event. Ecologically, the agaves are keystone species on which numerous animal species depend for their subsistence due to the large amounts of pollen and nectar they produce, that support many pollinators, including bats, perching birds, hummingbirds, moths, and bees. Moreover, in many regions of Mexico and in the southwestern United States, agaves are dominant species. We describe the contributions of H. S. Gentry to the understanding of agaves and review recent advances on the study of the ecology and evolution of the genus. We analyze the present and inferred past distribution patterns of different species in the genus, describing differences in their climatic niche and adaptations to dry conditions. We interpret these patterns using molecular clock data and phylogenetic analyses and information of their coevolving pollinators and from phylogeographic, morphological, and ecological studies and discuss the prospects for their future conservation and management. 相似文献
108.
Héctor M. Sarabia-Sainz Wilfrido Torres-Arreola Enrique Márquez-Ríos Hisila C. Santacruz-Ortega Ofelia Rouzaud-Sández Elisa M. Valenzuela-Soto Alexel J. Burgara-Estrella Josafat Marina Ezquerra-Brauer 《Food biophysics》2017,12(4):491-499
The chemical structure, thermal denaturation and nanostructure of collagen, obtained from a cation-exchange separation of the mantle, fins and tentacles of jumbo squid (Dosidicus gigas), were comparatively studied. The main idea of this work, was to provide an in-depth understanding of the interdependence between pyridinoline (Pyr) content, helix chemical structure and nanostructure of squid collagen with squid tissue firmness. The tentacles required more shear force and its collagen presented the higher temperature and enthalpy of transition, than the mantle and fins. The tentacle firmness may be explained by the relatively higher imino amino acid content, proline and lysine hydroxylation degrees and Pyr content of its collagen. Moreover, among the regions studied, the collagen from the tentacles had a more intense β band chain. Also, the Fourier transform infrared analysis and Raman spectra, implied that the collagen in the tentacles, was more intermolecularly ordered than the mantle and fins. Consistent with these results, a comparative evaluation of the surface morphology of the three regions, with atomic force microscopy, suggested a more ordered collagen structure in the tentacles (lower roughness values). Based on the above, collagen from tentacles has a higher degree of molecular order that sustains a higher muscle firmness compared to that of other anatomical regions. 相似文献
109.
Graciela S. Diniz Anita F. Silva Ofelia Q. F. Araújo Ricardo M. Chaloub 《Journal of applied phycology》2017,29(2):821-832
The utilization of microalgae for wastewater treatment represents an attractive opportunity for wastewater valorization through the use of the produced biomass. Five strains of microalgae were isolated from municipal wastewater and grown in autoclaved and non-autoclaved effluent at 30 °C and 150 μmol photons m?2 s?1 to study biomass production, nutrient removal, and the biochemical composition of the biomass. All strains reached high biomass productivity (35.6 to 54.2 mg dry weight L?1 day?1) within 4 days of batch culturing. In this period, ammonium-N and phosphate were reduced by more than 60 and 90 %, respectively. The high growth rate (0.57 to 1.06 day?1) ensured a rapid removal of nutrients and thereby a short retention time. By the fourth day of cultivation, the algal biomass contained 32 % protein, but only 11 % lipids and 18 % carbohydrates. It was found that the biomass was a suitable raw material for biogas production by anaerobic digestion. Biodigestion of obtained biomass was simulated by employing the Aspen HYSYS modeling software, resulting in methane yields comparable to those found in the literature. The elemental analysis of the algal biomass showed very low concentrations of pollutants, demonstrating the potential of use of the digestate from biodigestion as a bio-fertilizer. 相似文献
110.
Rodrigo Garza-Galindo Ofelia Morton-Bermea Elizabeth Hernández-Álvarez Sara L. Ordoñez-Godínez Omar Amador-Muñoz Laura Beramendi-Orosco 《人类与生态风险评估》2020,26(5):1164-1174
AbstractPlatinum (Pt) concentrations in PM2.5 were evaluated by means of inductively coupled plasma mass spectrometry (ICP-MS) to evaluate the spatial and temporal behavior and to assess trends. Samples were taken from five representative sites in the Mexico City Metropolitan Area (MCMA): Tlalnepantla-northwest (NW), San Agustin-northeast (NE), La Merced -center (C), Coyoacan-southwest (SW), and Universidad Autonoma Metropolitana Iztapalapa-southeast (SE). Under three weather conditions: dry warm (DW-April), rainy (R-August), and dry cold (DC-November) in 2013. We found that the PM2.5 median mass concentration was 24?μg m?3?±?15?μg m?3 while Pt concentration was 55?pg m?3?±?15?pg m?3 (median, interquartile range). Seasonal trend was identified: the concentrations decreased significantly in the following order DC?>?R>DW. No spatial distribution was observed. Interestingly, among other meteorically parameters, wind intensity resulted to be the major factor for the dispersion of Pt in PM2.5 in MCMA. Furthermore, we found that Pt concentrations increased significantly by 19.6% between 2011 and 2013. Regardless of the increase in Pt, carbon monoxide (CO) levels decreased opposite to a rise in vehicular fleet. These results urge for environment public policies that address the upward tendency of Pt levels especially in urban areas. 相似文献