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Sexually dimorphic characters have two-fold complexities in pattern formation as they have to get input from both somatic sex determination as well as the positional determining regulators. Sex comb development in Drosophila requires functions of the somatic sex-determining gene doublesex and the homeotic gene Sex combs reduced. Attempts have not been made to decipher the role of dsx in imparting sexually dimorphic expression of SCR and the differential function of sex-specific variants of dsx products in sex comb development. Our results in this study indicate that male-like pattern of SCR expression is independent of dsx function, and dsx F must be responsible for bringing about dimorphism in SCR expression, whereas dsx M function is required with Scr for the morphogenesis of sex comb. 相似文献
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Effect of bilirubin on toxicity induced by trifluoperazine, dibucaine and praziquantel to erythrocytes 总被引:1,自引:0,他引:1
Unconjugated bilirubin (UCB), like trifluoperazine (TFP), dibucaine (DBC) and praziquantel (PZQ), induces erythrocyte morphological changes, lysis and lipid exfoliation. In the present study we determined whether TFP, DBC and PZQ toxicity to erythrocytes was potentiated or reverted by UCB. Human erythrocytes were either treated or non-treated with 34.2 micromol/L UCB for 10 min prior to the incubation with toxic concentrations of TFP (0.12 mmol/L), DBC (1.5 mmol/L) or PZQ (3.0 mmol/L), for 1 h (37 degrees C). Studies of toxic effects included morphological analysis of erythrocytes, evaluation of hemoglobin release and loss of membrane lipids. Although UCB has an echinocytogenic effect, its co-incubation with TFP or PZQ did not alter the stomatocytogenic effect of the drug but enhanced DBC-induced stomatocytosis. Cell fusion was a common feature in experiments with DBC. Injurious effect of DBC to erythrocytes was potentiated by UCB as manifested by a marked increase in hemolysis (171%, p<0.05), and in elution of membrane cholesterol (73%, p<0.01) and phospholipids (123%, p<0.01). In opposite, toxic events produced by TFP and PZQ to erythrocytes were not aggravated by UCB. Interestingly, UCB prevented the loss of membrane cholesterol by PZQ (-36%, p<0.01), as well as that of phospholipids by TFP (-28%, p<0.05). These findings indicate that UCB potentiates DBC injury to erythrocytes, while protects membrane lipid elution by PZQ and TFP. Therefore, the relation of the benefits and risks of the administration of DBC to jaundiced patients should be carefully considered. 相似文献
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In the present study, we investigated the interaction of the non-ionic surfactants polyoxyethylene alkyl ethers (C(n)E(m)) with erythrocyte membranes. For this purpose we have performed hemolytic assays under isosmotic conditions with five surfactants in the 8 polyoxyethylene ether series. By applying to the hemolytic curves a quantitative treatment developed for the study of surface-active compounds on biomembranes, we could calculate the surfactant/lipid molar ratios for the onset of hemolysis (R(e)(sat)) and for complete hemolysis (R(e)(sol)). This approach also allowed the calculation of the binding constants for each surfactant to the erythrocyte membrane. Results in the C(n)E(m) series were compared to those obtained for Triton X-100, a well-known non-ionic surfactant with values of cmc and HLB in the range of the alkyl ethers studied. Inside the series the lytic effect increased with the more hydrophobic homologues (C(10)E(8)相似文献
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Thyroid status,but not insulin status,affects expression of avian uncoupling protein mRNA in chicken
Collin A Taouis M Buyse J Ifuta NB Darras VM Van As P Malheiros RD Moraes VM Decuypere E 《American journal of physiology. Endocrinology and metabolism》2003,284(4):E771-E777
The aim of this study was to investigate the hormonal regulation of the avian homolog of mammalian uncoupling protein (avUCP) by studying the impact of thyroid hormones and insulin on avUCP mRNA expression in chickens (Gallus gallus). For 3 wk, chicks received either a standard diet (control group), or a standard diet supplemented with triiodothyronine (T(3); T3 group) or with the thyroid gland inhibitor methimazole (MMI group). A fourth group received injections of the deiodinase inhibitor iopanoic acid (IOP group). During the 4th wk of age, all animals received two daily injections of either human insulin or saline solution. The results indicate a twofold overexpression of avUCP mRNA in gastrocnemius muscle of T3 birds and a clear downregulation (-74%) in MMI chickens compared with control chickens. Insulin injections had no significant effect on avUCP mRNA expression in chickens. This study describes for the first time induction of avUCP mRNA expression by the thermogenic hormone T(3) in chickens and supports a possible involvement of avUCP in avian thermogenesis. 相似文献
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Cardoso T. F. Bruscadin J. J. Afonso J. Petrini J. Andrade B. G. N. de Oliveira P. S. N. Malheiros J. M. Rocha M. I. P. Zerlotini A. Ferraz J. B. S. Mourão G. B. Coutinho L. L. Regitano L. C. A. 《Mammalian genome》2022,33(4):619-628
Mammalian Genome - Cis-acting effects of noncoding variants on gene expression and regulatory molecules constitute a significant factor for phenotypic variation in complex traits. To provide new... 相似文献
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Mukund A. Prabhu Narayanan Namboodiri Srinivas Prasad BV S.P. Abhilash Anees Thajudeen Kumar V.K. Ajith 《Indian pacing and electrophysiology journal》2015,15(6):286-290
Background
Electrical storm (ES) is a life threatening emergency. There is little data available regarding acute outcome of ES.Aims
The study aimed to analyze the acute outcome of ES, various treatment modalities used, and the factors associated with mortality.Methods
This is a retrospective observational study involving patients admitted with ES at our centre between 1/1/2007 and 31/12/2013.Results
41 patients (mean age 54.61 ± 12.41 years; 86.7% males; mean ejection fraction (EF) 44.51 ± 16.48%) underwent treatment for ES. Hypokalemia (14.63%) and acute coronary syndrome (ACS) (14.63%) were the commonest identifiable triggers. Only 9 (21.95%) patients already had an ICD implanted. Apart from antiarrhythmic drugs (100%), deep sedation (87.8%), mechanical ventilation (24.39%) and neuraxial modulation using left sympathetic cardiac denervation (21.95%) were the common treatment modalities used. Thirty-three (80.49%) patients could be discharged after a mean duration of 14.2 ± 2.31 days. Eight (19.5%) patients died in hospital. The mortality was significantly higher in those with EF < 35% compared to those with a higher EF (8 (42.11% vs 0 (0%), p = 0.03)). There was no significant difference in mortality between those with versus without a structural heart disease (8 (21.1% vs 0 (0%), p = 0.32)). Comparison of mortality an ACS with ES versus ES of other aetiologies (3 (50%) vs 5 (14.29) %, p = 0.076)) showed a trend towards significance.Conclusion
With comprehensive treatment, there is reasonable acute survival rate of ES. Hypokalemia and ACS are the commonest triggers of ES. Patients with low EF and ACS have higher mortality. 相似文献8.
de Lira FA Farias Mde S de Figueiredo AF Gil Fdos S dos Santos MA Malheiros BV Ferreira JE Pinheiro JC Treu-Filho O Kondo RT 《Journal of molecular modeling》2011,17(7):1621-1624
In a previous article, we used Hartree-Fock (HF) theory to study the piezoelectricity in BaTiO3. In this paper, we applied the Douglas-Kroll-Hess second order scalar relativistic method to investigate the possible piezoelectric
properties in the perovskite YFeO3 structure, which has not yet been studied experimentally. The 30s20p13d and 31s21p17d Gaussian basis sets for the Fe (5D) and Y (2D) atoms, respectively, were built with the Generator Coordinate HF method. After contraction to [13s7p5d] and [13s8p7d],
in combination with the 20s14p/6s4p basis set for the O (3P) atom from literature, they had their quality evaluated using calculations of the total and the orbital energies for the
2FeO+1 and 1YO+1 fragments. The dipole moment, the total energy, and the total atomic charges in YFeO3 in Cs space group were calculated. The results and the analysis lead us to believe that the perovskite YFeO3 does not present piezoelectric properties. 相似文献
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F M da Cunha T S Fr?de G L Mendes A Malheiros V Cechinel Filho R A Yunes J B Calixto 《Life sciences》2001,70(2):159-169
This study evaluates further the anti-inflammatory and anti-allergic properties of polygodial, a sesquiterpene extracted from the barks plant Drymis winteri (Winteraceae). Polygodial (12.8-128.1 micromol/kg, i.p.) 30 min prior, inhibited significantly the mouse paw oedema induced by prostaglandin E2, bradykinin (BK) substance P (SP), dextran, platelet activating factor (PAF) or carrageenan. Polygodial also inhibited arachidonic acid-, capsaicin- and croton oil-induced ear oedema in mice. Polygodial (42.7 micromol/kg, i.p.), significantly inhibited both exudation and cell influx when assessed in the pleurisy induced by SP and histamine, and to a less extent the inflammatory response caused by carrageenan, PAF, BK and des-Arg9-BK. Finally, polygodial (4.2-42.7 micromol/kg, i.p.) produced dose-related inhibition of paw oedema induced by ovalbumin, protecting in a time-dependent manner the anaphylactic shock induced by endovenous administration of ovalbumin in animals which had been actively sensitised by this antigen. These and our previous results indicate that the major component present in the bark of the plant D. winteri, the sesquiterpene polygodial exerts an interesting anti-inflammatory and anti-allergic properties when assessed in rats and mice. 相似文献
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During their relatively short commercial lifespan of six weeks, broiler chickens undergo very pronounced age- or body weight-related changes in metabolic rate and body composition. The present study was aimed to assess the age-related changes in glucose oxidation rate of broiler chickens by using 13C-labeled glucose. The methodology for this breath test needed to be established first. Broiler chickens aged from two to six weeks were placed in open-circuit respiration cells and received a single intubation of U-13C6-glucose, followed by breath sampling for 4 hours and mass spectrometric analysis of 13C: 12C ratio in the exhaled air. Simultaneously, CO2 concentration in the respiration cell air was continuously monitored in order to calculate the cumulative percentage dose recovery (CPDR). With respect to the methodology, an oral dose of 2 mg U-13C6-glucose per kg body weight while maintaining a CO2 in the concentration of 0.4 to 0.5% was considered to be optimal. The three-parameter Gompertz curve fitted the CPDR values very well. Pronounced age-related changes in exogenous glucose oxidation rates in rapidly growing meat-type chickens were assessed. Young broiler chickens spend only a relatively low percentage of ingested glucose for immediate oxidation. In contrast, broiler chickens approaching the age of maximal absolute growth rate oxidize a greater proportion of the recently ingested glucose relative to the non-oxidative disposal pathways. This shift in the exogenous partitioning is discussed in relation to age-dependent changes in glucose turnover, lipid oxidation and deposition and metabolic heat production. 相似文献