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971.
Gisela Di Giusto Pilar Flamenco Valeria Rivarola Juan Fernández Luciana Melamud Paula Ford Claudia Capurro 《Journal of cellular biochemistry》2012,113(12):3721-3729
We have previously demonstrated that in renal cortical collecting duct cells (RCCD1) the expression of the water channel Aquaporin 2 (AQP2) raises the rate of cell proliferation. In this study, we investigated the mechanisms involved in this process, focusing on the putative link between AQP2 expression, cell volume changes, and regulatory volume decrease activity (RVD). Two renal cell lines were used: WT‐RCCD1 (not expressing aquaporins) and AQP2‐RCCD1 (transfected with AQP2). Our results showed that when most RCCD1 cells are in the G1‐phase (unsynchronized), the blockage of barium‐sensitive K+ channels implicated in rapid RVD inhibits cell proliferation only in AQP2‐RCCD1 cells. Though cells in the S‐phase (synchronized) had a remarkable increase in size, this enhancement was higher and was accompanied by a significant down‐regulation in the rapid RVD response only in AQP2‐RCCD1 cells. This decrease in the RVD activity did not correlate with changes in AQP2 function or expression, demonstrating that AQP2—besides increasing water permeability—would play some other role. These observations together with evidence implying a cell‐sizing mechanism that shortens the cell cycle of large cells, let us to propose that during nutrient uptake, in early G1, volume tends to increase but it may be efficiently regulated by an AQP2‐dependent mechanism, inducing the rapid activation of RVD channels. This mechanism would be down‐regulated when volume needs to be increased in order to proceed into the S‐phase. Therefore, during cell cycle, a coordinated modulation of the RVD activity may contribute to accelerate proliferation of cells expressing AQP2. J. Cell. Biochem. 113: 3721–3729, 2012. © 2012 Wiley Periodicals, Inc. 相似文献
972.
973.
Moro C Jouan MG Rakotovao A Toufektsian MC Ormezzano O Nagy N Tosaki A de Leiris J Boucher F 《American journal of physiology. Heart and circulatory physiology》2007,293(5):H3014-H3019
Previous studies have shown that 1 wk after permanent coronary artery ligation in rats, some cellular mechanisms involving TNF-alpha occur and contribute to the development of cardiac dysfunction and subsequent heart failure. The aim of the present study was to determine whether similar phenomena also occur after ischemia-reperfusion and whether cytokines other than TNF-alpha can also be involved. Anesthetized male Wistar rats were subjected to 1 h coronary occlusion followed by reperfusion. Cardiac geometry and function were assessed by echocardiography at days 5, 7, 8, and 10 postligation. Before death, heart function was assessed in vivo under basal conditions, as well as after volume overload. Finally, hearts were frozen for histoenzymologic assessment of infarct size and remodeling. The profile of cardiac cytokines was determined by ELISA and ChemiArray on heart tissue extracts. As expected, ischemia-reperfusion induced a progressive remodeling of the heart, characterized by left ventricular free-wall thinning and cavity dilation. Heart function was also decreased in ischemic rats during the first week after surgery. Interestingly, a transient and marked increase in TNF-alpha, IL-1beta, IL-6, cytokine-induced neutrophil chemoattractant (CINC) 2, CINC3, and macrophage inflammatory protein-3alpha was also observed in the myocardium of myocardial ischemia (MI) animals at day 8, whereas the expression of anti-inflammatory interleukins IL-4 and IL-10 remained unchanged. These results suggest that overexpression of proinflammatory cytokines occurring during the first week after ischemia-reperfusion may play a role in the adaptative process in the myocardium and contribute to early dysfunction and remodeling. 相似文献
974.
Mônica Pezenatto dos Santos Mayara Luciana Sallas Diana Zapparoli Wilson Aparecido Orcini Elizabeth Chen Marilia de Arruda Cardoso Smith Spencer L. Marques Payão Lucas Trevizani Rasmussen 《Journal of cellular biochemistry》2019,120(6):9448-9454
The process of combating neoplasms and mononuclear cells, and during H. pylori infection, several pro-inflammatory and anti-inflammatory cytokines are synthesized. In view of the involvement of the IL-6 law and the presence of H. pylori in the development of gastric diseases, the present study aimed to characterize the promoter-region polymorphism −597 (G/A) (rs1800797), −572 (C/G) (rs1800796), and −174 (G/C) (rs1800795) by PCR-RFLP in 375 gastric biopsy specimens from patients with peptic symptoms. A total of 375 samples were analyzed: 87 patients (without lesion without gastric tissue); 236 patients with gastritis and 52 patients with gastric cancer analyzed the PCR-RFLP techniques. All the results were normalized in relation to the presence of H. pylori. The frequencies of the three polymorphisms were compared in the Control vs Gastritis groups and a statistically significant test observed: −174 (G/C) (OR: 1.27; 95% CI: 0.84–1.93; P = 0.26), 572 (C/G) (OR: 1.42; 95% CI: 0.78–2.59; P = 0.25), and 597 (G/A) (OR: 0.98; 95% CI, 0.64–1.52; P = 0.94). Similar results were obtained when the gastric cancer group was compared to the control group: −174 (G/C) (OR: 1.27; 95% CI: 0.66–2.47; P = 0.47), −572 (C/G) (OR: 1.07; 95% CI: 0.43–2.68; P = 0.88), and −597 (G/A) (OR: 1.01; 95% CI, 0.5–0.9; P = 0.99). The haplotypes were and were not observed statistically significant differences. In conclusion, we found no correlations between any of the three polymorphisms in the IL-6 gene analyzed in this study and a higher risk of gastritis or gastric cancer. 相似文献
975.
Tigressa H. S. Rodrigues Gustavo A. S. Pinto Luciana R. B. Gonçalves 《Biotechnology and Bioprocess Engineering》2008,13(5):571-576
In this study, the optimization of tannase production by solid state fermentation was investigated using cashew apple bagasse
(CAB), an inexpensive residue produced by the cashew apple agroindustry, as a substrate. To accomplish this, CAB was enriched
with 2.5% (w/w) tannic acid and 2.5% (w/w) ammonium sulphate and then moistened with water (60 mL/100 g of dry CAB). The influence
of inoculum concentration (104 to 107 spores/g), temperature (20, 25, 30, and 35°C) and several additional carbon sources (glucose, starch, sucrose, maltose, analytical
grade glycerol, and glycerol produced during biodiesel production) on enzyme production by Aspergillus oryzae was then evaluated. Supplementation with maltose and glycerol inhibited tannase synthesis, which resulted in lower enzyme
activity. Starch and sucrose supplementation increased enzyme production, but decreased the enzyme productivity. The maximum
tannase activity (4.63 units/g of dry substrate) was obtained at 30°C, using 107 spores/g and 1.0% (w/v) sucrose as an additional carbon source. 相似文献
976.
Buss Carlos Eduardo Afonso Juliana de Oliveira Priscila S. N. Petrini Juliana Tizioto Polyana Cristine Cesar Aline S. M. Gustani-Buss Emanuele Cristina Cardoso Tainã Figueiredo Rovadoski Gregori A. da Silva Diniz Wellison Jarles de Lima Andressa Oliveira Rocha Marina Ibelli Pereira Andrade Bruno Gabriel Nascimento Wolf Jason B. Coutinho Luiz Lehmann Mourão Gerson Barreto de Almeida Regitano Luciana Correia 《Mammalian genome》2023,34(1):90-103
Mammalian Genome - Feed-efficient cattle selection is among the most leading solutions to reduce cost for beef cattle production. However, technical difficulties in measuring feed efficiency traits... 相似文献
977.
Four hundred and fifty wild-caught owl monkeys (Aotus nancymai) were shipped from Iquitos, Peru to Richland, Washington. Mortality and body weight changes from the time of shipment to 30 days after arrival were evaluated using age, sex, and transit time as comparison criteria. No association between mortality and sex, age, or transit time was observed. The mortality percentage from shipment to 30 days after arrival was 2.44%. Both age and transit time had a significant effect on weight changes, but sex did not. Shipping procedures are described. 相似文献
978.
979.
Carlos J. F. Castillo María A. Moro Mercedes Del Valle Antonio Sillero Antonio G. Garcia Maria A. G. Sillero 《Journal of neurochemistry》1992,59(2):723-732
Secretion of adenosine(5')tetraphospho(5')adenosine (Ap4A) and ATP from perfused bovine adrenal glands stimulated with acetylcholine or elevated potassium levels was measured and compared with that of catecholamines. We have found a close correlation between the release of Ap4A and catecholamines elicited with all the secretagogues used in the presence of either Ca2+ or Ba2+, suggesting co-release of both constituents from the chromaffin granules. By contrast, ATP secretion, as measured with luciferase, showed a significantly different time course regardless of the secretagogue used. ATP secretion consistently decreased after 1-2 min of stimulation at a time when Ap4A and catecholamine secretions were still increasing. Measures of degradation of injected [3H]ATP to the gland during stimulation showed little difference in the level of uptake or decomposition of ATP throughout the pulse. However, a reexamination of ATP secretion by monitoring its products of degradation (AMP, adenosine, and inosine) by HPLC techniques showed that Ap4A, ATP, and catecholamines are indeed secreted in parallel from the perfused adrenal gland. 相似文献
980.
Petronio Pasquali Mauro Degli Esposti Laura Landi Luciana Cabrini Giorgio Lenaz 《Journal of bioenergetics and biomembranes》1985,17(5):283-294
Depletion of endogenous ubiquinone by pentane extraction of mitochondrial membranes lowered succinate-ferricyanide reductase activity, whereas quinone reincorporation restored the enzymatic activity as well as antimycin sensitivity. The oxidant-induced cytochromeb extrareduction, normally found upon ferricyanide pulse in intact mitochondria in the presence of antimycin, was lost in ubiquinone-depleted membranes, even if cytochromec was added. Readdition of ubiquinone-2 restored the oxidant-induced extrareduction with an apparent half saturation at 1 mol/molbc
1 complex saturating at about 5 mol/mol. These findings demonstrate a requirement for the ubiquinone pool of the cytochromeb extrareduction. Since the initial rates of cytochromeb reoxidation upon ferricyanide addition, in the presence of antimycin, did not saturate by any ferricyanide concentration in ubiquinone-depleted mitochondria, a direct chemical reaction between ferricyanide and reduced cytochromeb was postulated. The fact that such direct reaction is much faster in ubiquinone-depleted mitochondria may explain the lower antimycin sensitivity of the succinate ferricyanide reductase activity after removal of endogenous ubiquinone. 相似文献