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991.
Role of the Src family kinase Lyn in TxA2 production, adenosine diphosphate secretion, Akt phosphorylation, and irreversible aggregation in platelets stimulated with gamma-thrombin 总被引:1,自引:4,他引:1 下载免费PDF全文
Members of the Src family of kinases are abundant in platelets. Although their localization is known, their role(s) in platelet function are not well understood. Lyn is a Src-family kinase that participates in signal transduction pathways elicited by collagen-related peptide; it has also been implicated through biochemical studies in the regulation of von Willebrand factor signaling. Here, we provide evidence that Lyn plays a role in gamma-thrombin activation of platelets. Unlike the wild-type platelets, platelets from Lyn-deficient mice do not undergo irreversible aggregation, produce thromboxane A2, or secrete adenosine diphosphate in response to submaximal gamma-thrombin concentrations that cause secretion-dependent irreversible aggregation. Phosphorylation of Akt, a downstream effector of phosphatidylinositol 3-kinase, also requires a higher concentration of gamma-thrombin in Lyn-deficient platelets than in wild-type platelets. These findings demonstrate that Lyn signaling is required for thrombin induction of secretion-dependent platelet aggregation. Specifically, Lyn is required under these conditions to enable thrombin-induced TxA2 production and adenosine diphosphate secretion, necessary steps in secretion-dependent platelet aggregation. 相似文献
992.
José Cortez Assunção Júnior Hugo Jario de Almeida Silva José Felipe Costa da Silva Rafaela da Silva Cruz Caio Alano de Almeida Lins Marcelo Cardoso de Souza 《Journal of bodywork and movement therapies》2018,22(2):455-459
Introduction
The importance of physical exercise for patients with fibromyalgia (FM) is very clear in the literature. Dancing is a type of aerobic exercise that has great acceptance. In addition to the beneficial effects of aerobic exercise, Zumba works on motor coordination and also has socializing as a part that should be included in patients with fibromyalgia.Objectives
To evaluate the effectiveness of Zumba dancing in improving pain, functional capacity, quality of sleep and quality of life of women with fibromyalgia.Design
A pre-post treatment design.Methods
We evaluated 19 women with fibromyalgia, selected by convenience. Data were collected in the second half of 2016. Zumba dancing was performed twice a week for 12 weeks. Patients were evaluated at week 0 (T0) and at week 12 (T12), by the following instruments: VAS (Visual Analogic Scale), Likert Scale, TUG (Timed Up an Go Test), 6MWT (Six-minute Walk Test), FIQ (Fibromyalgia Impact Questionnaire), PSQI (Pittsburgh Sleep Quality Index), ESS (Epworth Sleepiness Scale) and SF-36 quality of life.Results
We found differences in pain (VAST0 = 6.21 and VAST12 = 4.53) with p = 0.001 and in the domain physical functioning of SF36 (T0 = 42.37 and T12 = 52.11) with p = 0.04. No differences were found for the other variables between the times.Conclusion
Zumba dancing as a form of treatment for three months for patients with fibromyalgia was effective in improving pain and physical functioning. Future controlled and randomized clinical trials should be performed to improve the evidence of Zumba dancing in women with fibromyalgia. 相似文献993.
Maria Fernanda Hussid Felipe Xerez Cepeda Camila P. Jordo Rafaela R. P. Lopes-Vicente Leslie Virmondes Keyla Y. Katayama Ezequiel F. de Oliveira Luis V. F. Oliveira Fernanda Marciano Consolim-Colombo Ivani Credidio Trombetta 《Arquivos brasileiros de cardiologia》2021,116(4):795
Background:Obesity affects adolescence and may lead to metabolic syndrome (MetS) and endothelial dysfunction, an early marker of cardiovascular risk. Albeit obesity is strongly associated with obstructive sleep apnea (OSA), it is not clear the role of OSA in endothelial function in adolescents with obesity.Objective:To investigate whether obesity during adolescence leads to MetS and/or OSA; and causes endothelial dysfunction. In addition, we studied the possible association of MetS risk factors and apnea hypopnea index (AHI) with endothelial dysfunction.Methods:We studied 20 sedentary obese adolescents (OA; 14.2±1.6 years, 100.9±20.3kg), and 10 normal-weight adolescents (NWA, 15.2±1.2 years, 54.4±5.3kg) paired for sex. We assessed MetS risk factors (International Diabetes Federation criteria), vascular function (Flow-Mediated Dilation, FMD), functional capacity (VO2peak) and the presence of OSA (AHI>1event/h, by polysomnography). We considered statistically significant a P<0.05.Results:OA presented higher waist (WC), body fat, triglycerides, systolic (SBP) and diastolic blood pressure (DBP), LDL-c and lower HDL-c and VO2peak than NWA. MetS was presented in the 35% of OA, whereas OSA was present in 86.6% of OA and 50% of EA. There was no difference between groups in the AHI. The OA had lower FMD than NWA (6.17±2.72 vs. 9.37±2.20%, p=0.005). There was an association between FMD and WC (R=-0.506, p=0.008) and FMD and SBP (R=-0.493, p=0.006).Conclusion:In adolescents, obesity was associates with MetS and caused endothelial dysfunction. Increased WC and SBP could be involved in this alteration. OSA was observed in most adolescents, regardless of obesity. (Arq Bras Cardiol. 2021; 116(4):795-803) 相似文献
994.
Sánchez-Criado JE Martín De Las Mulas J Bellido C Tena-Sempere M Aguilar R Blanco A 《Neuroendocrinology》2004,79(5):247-258
Estrogen (E) is a key regulator of the synthesis and secretion of pituitary reproductive hormones [luteinizing hormone (LH), follicle-stimulating hormone (FSH) and prolactin (PRL)]. Until recently, it was thought that all biological actions of E at the pituitary were manifested through a single E receptor (R). The pituitary, like many other reproductive tissues, expresses two isoforms of ER, alpha and beta, both activated by E. The relative contribution of alpha and beta forms in E regulatory actions is largely unknown. To this end, 2-week-old ovariectomized (OVX) rats were injected over 3 days with 25 microg estradiol benzoate (EB), 1.5 mg of propylpyrazole triol (PPT), a selective ERalpha agonist, 1.5 mg of the selective ERbeta agonist diarylpropionitrile (DPN) or a combination of PPT and DPN. Controls were injected with 0.2 ml oil. At 10:00 h on the day after treatment, trunk blood was collected to determine serum concentration of LH, FSH and PRL, and pituitaries were processed for RT-PCR analysis of total (A+B) progesterone receptor (PR) mRNA, immunocytochemistry of PR and incubation. Pituitaries from each of the five groups were incubated in DMEM, with or without 20 nM of the antiprogestin at the receptor ZK299, for 3 h with: 10(-8)M 17beta-estradiol, 10(-6)M PPT, 10(-6)M DPN, PPT+DPN or medium alone, respectively, to determine LH, FSH and PRL secretion, and, when challenged with two pulses of 15 min 1 h apart of 10(-8)M gonadotropin-releasing hormone (GnRH) (GnRH self-priming). EB, PPT and PPT+DPN treatments increased PR mRNA and the number and intensity of nuclei immunoreactive (IR) for PR in gonadotropes, and reduced the number of gonadectomy cells. Like E, PPT alone or in combination with DPN stimulated PRL secretion, increased basal and GnRH-stimulated LH and FSH secretion and induced GnRH self-priming in the absence of ZK299 in the incubation medium. DPN alone had only a significant E-like effect on gonadectomy cells and IR-PR, but not on GnRH self-priming. In addition, while DPN lacked an agonistic action on peripheral tissue and serum pituitary reproductive hormones concentration, EB, PPT and PPT+DPN induced similar uterine ballooning and vaginal cornification, and increased and decreased, respectively, serum concentrations of PRL and gonadotropins. Overall, these results indicate that most of these E actions on the pituitary are exerted through the ERalpha isoform. The finding that activation of ERbeta with its selective DPN agonist had an estrogenic effect on IR-PR nuclei, but not on GnRH self-priming, a characteristic ERalpha-mediated effect of E, suggests that the biological action of E at the pituitary may involve both isoforms of ER. 相似文献
995.
Rafaela Garcia Santos de Andrade Vivien Schmeling Piccin Juliana Araújo Nascimento Fernanda Madeiro Leite Viana Pedro Rodrigues Genta Geraldo Lorenzi-Filho 《Jornal brasileiro de pneumologia》2014,40(6):658-668
Continuous positive airway pressure (CPAP) is the gold standard for the treatment of obstructive sleep apnea (OSA). Although CPAP was originally applied with a nasal mask, various interfaces are currently available. This study reviews theoretical concepts and questions the premise that all types of interfaces produce similar results. We revised the evidence in the literature about the impact that the type of CPAP interface has on the effectiveness of and adherence to OSA treatment. We searched the PubMed database using the search terms "CPAP", "mask", and "obstructive sleep apnea". Although we identified 91 studies, only 12 described the impact of the type of CPAP interface on treatment effectiveness (n = 6) or adherence (n = 6). Despite conflicting results, we found no consistent evidence that nasal pillows and oral masks alter OSA treatment effectiveness or adherence. In contrast, most studies showed that oronasal masks are less effective and are more often associated with lower adherence and higher CPAP abandonment than are nasal masks. We concluded that oronasal masks can compromise CPAP OSA treatment adherence and effectiveness. Further studies are needed in order to understand the exact mechanisms involved in this effect. 相似文献
996.
Rafael Vidal-Perez Raquel V zquez-Garc a Gonzalo Barge-Caballero Alberto Bouzas-Mosquera Rafaela Soler-Fernandez Jose Maria Larra aga-Moreira Maria Generosa Crespo-Leiro Jose Manuel Vazquez-Rodriguez 《World journal of cardiology》2020,12(12):599-614
Amyloidosis is an infiltrative disease caused by extracellular protein deposition that has accumulated a lot of scientific production in recent years. Different types of amyloidosis can affect the heart. Transthyretin amyloidosis and light chain amyloidosis are the two most common types of cardiac amyloidosis. These entities have a poor prognosis, so accurate diagnostic techniques are imperative for determining an early therapeutic approach. Recent advances in cardiac imaging and diagnostic strategies show that these tools are safe and can avoid the use of invasive diagnostic techniques to histological confirmation, such as endomyocardial biopsy. We performed a review on the diagnostic and prognostic implications of different cardiac imaging techniques in cardiac amyloidosis. We mainly focus on reviewing echocardiography, cardiac magnetic resonance, computed tomography and nuclear imaging techniques and the different safety measurements that can be done with each of them. 相似文献
997.
María‐Isabel Moreno‐Carralero Juan‐Antonio Muñoz‐Muñoz Nuria Cuadrado‐Grande Rafaela López‐Rodríguez María José Hernández‐Alfaro Alejandro del‐Castillo‐Rueda Rafael Enríquez‐de‐Salamanca Manuel Méndez María‐Josefa Morán‐Jiménez 《American journal of hematology》2014,89(7):689-694
Ferroportin disease is an inherited disorder of iron metabolism and is caused by mutations in the ferroportin gene (SLC40A1). We present a patient with hyperferritinemia, iron overload in the liver with reticuloendothelial distribution and also in the spleen, and under treatment with erythropheresis. A molecular study of the genes involved in iron metabolism (HFE, HJV, HAMP, TFR2, SLC40A1) was undertaken. In vitro functional studies of the novel mutation found in the SLC40A1 gene was performed. The patient was heterozygous for a novel mutation, c.386T>C (p.L129P) in the SLC40A1 gene; some of his relatives were also heterozygous for this mutation. In vitro functional studies of the L129P mutation on ferroportin showed it impairs its capacity to export iron from cells but does not alter its sensitivity to hepcidin. These findings and the iron overload phenotype of the patient suggest that the novel mutation c.386T>C (p.L129P) in the SLC40A1 gene has incomplete penetrance and causes the classical form of ferroportin disease. Am. J. Hematol. 89:689–694, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
998.
Svjetlana Medjakovic Alfred Zoechling Petra Gerster Margarita M. Ivanova Yun Teng Carolyn M. Klinge Barbara Schildberger Michael Gartner Alois Jungbauer 《Environmental toxicology》2014,29(10):1201-1216
Nonpersistent pesticides are considered less harmful for the environment, but their impact as endocrine disruptors has not been fully explored. The pesticide Switch was applied to grape vines, and the maximum residue concentration of its active ingredients was quantified. The transactivation potential of the pesticides Acorit, Frupica, Steward, Reldan, Switch, Cantus, Teldor, and Scala and their active compounds (hexythiazox, mepanipyrim, indoxacarb, chlorpyrifos‐methyl, cyprodinil, fludioxonil, boscalid, fenhexamid, and pyrimethanil) were tested on human estrogen receptor α (ERα), androgen receptor (AR) and arylhydrocarbon receptor (AhR) in vitro. Relative binding affinities of the pure pesticide constituents for AR and their effect on human breast cancer and prostate cancer cell lines were evaluated. Residue concentrations of Switch's ingredients were below maximum residue limits. Fludioxonil and fenhexamid were ERα agonists (EC50‐values of 3.7 and 9.0 μM, respectively) and had time‐dependent effects on endogenous ERα‐target gene expression (cyclin D1, progesterone receptor, and nuclear respiratory factor 1) in MCF‐7 human breast cancer cells. Fludioxonil, mepanipyrim, cyprodinil, pyrimethanil, and chlorpyrifos‐methyl were AhR‐agonists (EC50s of 0.42, 0.77, 1.4, 4.6, and 5.1 μM, respectively). Weak AR binding was shown for chlorpyrifos‐methyl, cyprodinil, fenhexamid, and fludioxonil. Assuming a total uptake which does not take metabolism and clearance rates into account, our in vitro evidence suggests that pesticides could activate pathways affecting hormonal balance, even within permitted limits, thus potentially acting as endocrine disruptors. © 2013 Wiley Periodicals, Inc. Environ Toxicol 29: 1201–1216, 2014. 相似文献
999.
Alessandra V. Jager Fernando G. Tonin Pollyana C. M. C. Souto Rafaela T. Privatti Carlos A. F. Oliveira 《Toxins》2014,6(7):1996-2007
In the present study, a longitudinal assessment was carried out to evaluate the short-term human exposure to aflatoxins in Pirassununga region, São Paulo, Brazil, by determination of urinary aflatoxins by a liquid chromatography coupled to mass sprectrometry (UPLC-MS/MS) method. Sixteen volunteers with ages ranging from 14 to 55 years old were instructed to collect the early morning first urine four times every three months, from June 2011 to March 2012, totaling 64 samples. Aflatoxin M1 (AFM1) was found in 39 samples (61%) at levels ranging from 0.19 to 12.7 pg·mg−1 creatinine (mean: 1.2 ± 2.0 pg·mg−1 creatinine). Residues of aflatoxins B1, B2, G1, G2 and aflatoxicol were not identified in any urine sample. No significant difference was found among the AFM1 mean levels in urine samples collected in the four sampling periods. The levels of AFM1 found in urine samples indicate a low short-term exposure of the population studied to aflatoxins through the diet, although further investigations are needed to assess other long-term biomarkers of exposure to AFB1. 相似文献
1000.
Rafaela Silva Lamarca Ricardo Adriano Dorledo de Faria Maria Valnice Boldrin Zanoni Marcelo Nalin Paulo Clairmont Feitosa de Lima Gomes Youns Messaddeq 《RSC advances》2020,10(4):1838
In this study an impedimetric immunosensor was developed in order to determine ciprofloxacin (CIP) in wastewater samples, an emergent contaminant widely found in wastewater. To achieve this, an anti-ciprofloxacin antibody was immobilized on the surface of a printed carbon electrode. Then, the developed immunosensor was applied in wastewater samples from Université Laval residences (Québec, Canada) through the load transfer resistance (Rct) using [Fe(CN)6]3−/4− as a redox probe, and the average CIP concentration was found to be 2.90 × 10−4 μg mL−1. The observed Rct changes presented a linear relationship from CIP concentrations of 10−5 to 1.0 μg mL−1, with detection and quantification limits of 2.50 × 10−6 and 7.90 × 10−6 μg mL−1, respectively. The immunosensor presented high selectivity and repeatability, as well as a good recovery rate in wastewater samples (97%). Significant interference with other compounds was not observed. The proposed method requires only 30 μL of sample without the use of organic solvents or preceding sample preparation and/or extraction techniques. Moreover, the method is fast: only 20 min of incubation followed by 2 min of analysis time was sufficient to obtain the CIP concentration. The method''s estimated cost is U$ 2.00 per sample.In this study an impedimetric immunosensor was developed in order to determine ciprofloxacin (CIP) in wastewater samples, an emergent contaminant widely found in wastewater samples. 相似文献