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1.
Toxicol Appl Pharmacol ; 484: 116847, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38336252

RESUMO

Neonicotinoids (NNs) are commonly used pesticides that have a selective agonistic action on insect nicotinic acetylcholine receptors. Recent evidence has shown that NNs have adverse effects in the next generation of mammals, but it remains unclear how NNs transferred from dams to fetuses are distributed and accumulated in fetal tissues. Here, we aimed to clarify the tissue distribution and accumulation properties of the NN clothianidin (CLO) and its 6 metabolites in 7 tissues and blood in both dams and fetuses of mice administered CLO for a single day or for 9 consecutive days. The results showed that the total concentrations of CLO-related compounds in the brain and kidney were higher in fetuses than in dams, whereas in the liver, heart, and blood they were lower in fetuses. The multi-day administration increased the total levels in heart and blood only in the fetuses of the single administration group. In addition, dimethyl metabolites of CLO showed fetus/dam ratios >1 in some tissues, suggesting that fetuses have higher accumulation property and are thus at higher risks of exposure to CLO-related compounds than dams. These findings revealed differences in the tissue-specific distribution patterns of CLO and its metabolites between dams and fetuses, providing new insights into the assessment of the developmental toxicity of NNs.


Assuntos
Inseticidas , Praguicidas , Tiazóis , Camundongos , Animais , Praguicidas/toxicidade , Praguicidas/metabolismo , Distribuição Tecidual , Neonicotinoides/toxicidade , Neonicotinoides/metabolismo , Feto/metabolismo , Inseticidas/toxicidade , Inseticidas/metabolismo , Guanidinas/toxicidade , Guanidinas/metabolismo , Mamíferos
2.
Toxicol Appl Pharmacol ; 456: 116283, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36252886

RESUMO

Although neonicotinoids are among the major classes of pesticides that affect mammalian nervous systems, little is known about sex differences in their effects. This study aimed to examine whether the neurobehavioral effects of a neonicotinoid, clothianidin (CLO), differed between sexes. Male and female C57BL/6N mice were orally administered CLO (5 or 50 mg/kg) at or below the chronic no-observed-adverse-effect-level (NOAEL) and subjected to behavioral tests of emotional and learning functions. Changes in neuroactivity in several brain regions and the concentrations of CLO and its metabolites in blood and urine were measured. Acute CLO exposure caused sex-related behavioral effects; decreases in locomotor activities and elevation of anxiety-like behaviors were more apparent in males than in females. In addition, male-specific impairment of short- and long-term learning memory by CLO exposure was observed in both the novel recognition test and the Barnes maze test. Male-dominant increases in the number of c-fos positive cells were observed in the paraventricular thalamic nucleus in the thalamus and in the dentate gyrus in the hippocampus, which are related to the stress response and learning function, respectively. The concentrations of CLO and most metabolites in blood and urine were higher in males. These results support the notion that male mice are more vulnerable than females to the neurobehavioral effects of CLO and provide novel insights into the risk assessment of neonicotinoids in mammalian neuronal function.


Assuntos
Inseticidas , Animais , Feminino , Masculino , Camundongos , Inseticidas/toxicidade , Camundongos Endogâmicos C57BL , Neonicotinoides/toxicidade , Guanidinas/toxicidade , Mamíferos
3.
PLoS Pathog ; 14(9): e1007299, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30261081

RESUMO

BCL2 family proteins including pro-survival proteins, BH3-only proteins and BAX/BAK proteins control mitochondria-mediated apoptosis to maintain cell homeostasis via the removal of damaged cells and pathogen-infected cells. In this study, we examined the roles of BCL2 proteins in the induction of apoptosis in cells upon infection with flaviviruses, such as Japanese encephalitis virus, Dengue virus and Zika virus. We showed that survival of the infected cells depends on BCLXL, a pro-survival BCL2 protein due to suppression of the expression of another pro-survival protein, MCL1. Treatment with BCLXL inhibitors, as well as deficient BCLXL gene expression, induced BAX/BAK-dependent apoptosis upon infection with flaviviruses. Flavivirus infection attenuates cellular protein synthesis, which confers reduction of short-half-life proteins like MCL1. Inhibition of BCLXL increased phagocytosis of virus-infected cells by macrophages, thereby suppressing viral dissemination and chemokine production. Furthermore, we examined the roles of BCLXL in the death of JEV-infected cells during in vivo infection. Haploinsufficiency of the BCLXL gene, as well as administration of BH3 mimetic compounds, increased survival rate after challenge of JEV infection and suppressed inflammation. These results suggest that BCLXL plays a crucial role in the survival of cells infected with flaviviruses, and that BCLXL may provide a novel antiviral target to suppress propagation of the family of Flaviviridae viruses.


Assuntos
Flavivirus/patogenicidade , Proteína bcl-X/fisiologia , Animais , Apoptose/genética , Apoptose/fisiologia , Linhagem Celular , Sobrevivência Celular/genética , Sobrevivência Celular/fisiologia , Chlorocebus aethiops , Vírus da Dengue/patogenicidade , Vírus da Dengue/fisiologia , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Flavivirus/fisiologia , Infecções por Flavivirus/genética , Infecções por Flavivirus/patologia , Infecções por Flavivirus/fisiopatologia , Técnicas de Inativação de Genes , Células HEK293 , Interações Hospedeiro-Patógeno/genética , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Imunidade Inata , Camundongos , Camundongos Knockout , Modelos Biológicos , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/fisiologia , Células U937 , Células Vero , Replicação Viral/fisiologia , Zika virus/patogenicidade , Zika virus/fisiologia , Proteína bcl-X/antagonistas & inibidores , Proteína bcl-X/genética
4.
Masui ; 64(9): 902-10, 2015 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-26466489

RESUMO

Generally speaking, hypertension and arrhythmias are risk factors affecting anesthetic management and postoperative prognosis. However, the most recent ACC/AHA clinical guideline does not require the preoperative strict control of arterial pressure for patients with hypertension, since there has been not any definite evidence demonstrating that the preoperative control improves postoperative cardiovascular prognosis. On the other hand, the guideline recommends that preoperative management of patients with arrhythmias should be done according to the guideline for each arrhythmia. However, the guideline does not definitely mention the type of arrhythmias in which we should give priority to treatment of the arrhythmias over anesthesia for an elective operation. Presumably, the paucity of clinical studies to address this issue limits the definite recommendations. In patients with serious arrhythmias, such as ventricular tachycardia and atrial fibrillation with thrombus in the left atrium, preoperative clinical conference including anesthesiologist surgeons and cardiologists should be performed to decide the treatment plan for the patient Antihypertensive and antiarrhythmic drugs are frequently given in patients with hypertension or arrhythmias. These medicines as a general rule should be given until the morning of the operation day, although we do not have definite clinical evidence to support the advantage of the continuing.


Assuntos
Arritmias Cardíacas/complicações , Hipertensão/complicações , Anestesiologia/métodos , Humanos , Marca-Passo Artificial , Guias de Prática Clínica como Assunto , Fatores de Risco
6.
Toxicol Lett ; 342: 95-103, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33609686

RESUMO

Neonicotinoids, which act as agonists of the nicotinic acetylcholine receptors of insects, are widely used pesticides worldwide. Although epidemiological studies revealed that the detection amounts of neonicotinoids in urine are higher in the elderly population than other age-groups, there is no available information regarding the risks of neonicotinoids to older mammals. This study was aimed to investigate aging-related differences in the behavioral effects of the neonicotinoid pesticide clothianidin (CLO). We acutely administered a sub-NOAEL level (5 mg/kg) of CLO to adult (12-week-old) and aging (90-week-old) mice and conducted four behavioral tests focusing on the emotional behavior. In addition, we measured the concentrations of CLO and its metabolites in blood, brain and urine. There were age-related changes in most parameters in all behavioral tests, and CLO significantly decreased the locomotor activity in the open field test and elevated plus-maze test in the aging group, but not in the adult group. The concentrations of most CLO and its metabolites were significantly higher in the blood and brain and were slightly lower in the urine in the aging group compared to the adult group. These findings should contribute to our understanding of age-related differences in the adverse effects of neonicotinoids in mammals.


Assuntos
Comportamento Animal/efeitos dos fármacos , Guanidinas/toxicidade , Inseticidas/toxicidade , Neonicotinoides/toxicidade , Tiazóis/toxicidade , Envelhecimento , Animais , Relação Dose-Resposta a Droga , Guanidinas/administração & dosagem , Inseticidas/administração & dosagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neonicotinoides/administração & dosagem , Tiazóis/administração & dosagem
7.
Masui ; 59(8): 985-8, 2010 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-20715523

RESUMO

BACKGROUND: We are accustomed to right internal jugular vein (IJV) cannulation guided by pulsation for 20 years or more. This study was conducted to evaluate whether this method is a safe and certain method. METHODS: After obtaining informed consent, 100 elective surgical patients requiring central venous catheterization during perioperative period were randomly assigned to either the pulsation group in which IJV pulsation was used for a landmark of puncture or the US group in which IJV was recognized with ultrasonography before puncture. RESULTS: Pulsation was observed in 98 patients. Successful rate of first attempt with a 23 G seeking needle was 85.7% in the pulsation group and 86% in the US group. IJV was successfully cannulated at 1 pass in the entire pulsation group and 92% in the US group. The frequency of puncture with cannula was significantly lower in the pulsation group than that of the US group. Arterial puncture with the seeking needle was recorded in 3 patients in the US group. Successful rate of first attempt in this study was comparable to other studies using ultrasonographic guidance. CONCLUSIONS: Internal jugular vein cannulation by pulsation method is a safe and certain method.


Assuntos
Cateterismo/métodos , Veias Jugulares , Pulso Arterial , Idoso , Cateterismo Venoso Central/métodos , Feminino , Humanos , Masculino
8.
Ann Card Anaesth ; 23(2): 161-164, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32275029

RESUMO

Background: Prior experience may be important for successful placement of a pulmonary artery catheter (PAC). However, there is no report about the minimum number of the placement to reach acceptable technique for the catheter placement during residency. Aims: This study was designed to examine quality of the catheter placement and to assess the effect of prior experience. Setting and Design: Prospective, observational, cohort study. Methods: This study included eight residents and one experienced staff in our hospital. We prospectively examined the performance of placement of a PAC in eight residents for the first 2 months of their training period and one staff for previous 2 years. We examined the time required for the catheter placement and probability of ventricular arrhythmias during the placement. Each resident and the staff reported approximate number of past experience of the catheter placement according to the self-statement. In addition, we continued to examine the placement of a PAC in one resident with zero experience to show his improvement. Statistical Analysis: Statistical analysis was performed by Kruskal-Wallis test, Mann-Whitney test, or Fisher's exact test as appropriate and Benjamini and Hochberg method was used for multiple comparisons. Results: The catheter placement time and probability of the ventricular arrhythmias of two residents with zero experience of the placement were significantly larger than those of the staff. On the other hand, the placement quality of the other residents who experienced at least 20 PAC placements was not significantly different from that of the staff. The placement quality of one resident with zero experience became comparable with that of the staff after 20 placements. Conclusion: Our data suggested that about 20 catheter placements may be required to reach acceptable technical level for the PAC placement.


Assuntos
Anestesiologia/educação , Cateterismo/métodos , Competência Clínica/estatística & dados numéricos , Internato e Residência/métodos , Artéria Pulmonar , Idoso , Estudos de Coortes , Feminino , Humanos , Masculino , Estudos Prospectivos
9.
JA Clin Rep ; 6(1): 38, 2020 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-32447462

RESUMO

PURPOSE: A pulmonary artery catheter (PAC) has to pass the tricuspid and pulmonary valves for its proper placement. Although several factors were reported to hinder the placement, there have been no reports to identify the factors that prolong the individual time for passing through each valve. METHOD: We individually measured the time required for a PAC to pass through the tricuspid and pulmonary valves. We examined the effect of the following factors on those times: the patient's age, sex, height, weight, cardiothoracic ratio, tricuspid regurgitation, left ventricular ejection fraction, and the diameters of the sinus of Valsalva and of the sinotubular junction divided by the body surface area which represent the diameter of the aorta. Data were analyzed by multiple linear regression analysis after univariate analysis. RESULTS: The placement of a PAC was successful in all of 100 patients. The time required to pass through the pulmonary valve was significantly longer than that through the tricuspid valve (15 [10-28] s vs 9 [5-16] s, median [range], P < 0.01). The incidence of ventricular arrhythmias during passage through the pulmonary valve was significantly higher than that through the tricuspid valve (17% vs 0%, P < 0.01). Tricuspid regurgitation and the diameter of sinotubular junction had a significant positive association with the time required to advance a PAC through the pulmonary valve, although there was no significant factors that increased the time required to advance a PAC through the tricuspid valve. CONCLUSION: The time required to advance a PAC through the pulmonary valve is much longer than that to pass through the tricuspid valve. The diameter of aortic root and tricuspid regurgitation are significant factors that increased the time required to advance a PAC through the pulmonary valve.

10.
PLoS One ; 14(6): e0217105, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166966

RESUMO

Small-cell lung carcinoma (SCLC) and large-cell neuroendocrine lung carcinoma (LCNEC) are high-grade lung neuroendocrine tumors (NET). However, comparative protein expression within SCLC and LCNEC remains unclear. Here, protein expression profiles were obtained via mass spectrometry-based proteomic analysis. Weighted gene co-expression network analysis (WGCNA) identified co-expressed modules and hub genes. Of 34 identified modules, six were significant and selected for protein-protein interaction (PPI) network analysis and pathway enrichment. Within the six modules, the activation of cellular processes and complexes, such as alternative mRNA splicing, translation initiation, nucleosome remodeling and deacetylase (NuRD) complex, SWItch/Sucrose Non-Fermentable (SWI/SNF) superfamily-type complex, chromatin remodeling pathway, and mRNA metabolic processes, were significant to SCLC. Modules enriched in processes, including signal recognition particle (SRP)-dependent co-translational protein targeting to membrane, nuclear-transcribed mRNA catabolic process of nonsense-mediated decay (NMD), and cellular macromolecule catabolic process, were characteristically activated in LCNEC. Novel high-degree hub genes were identified for each module. Master and upstream regulators were predicted via causal network analysis. This study provides an understanding of the molecular differences in tumorigenesis and malignancy between SCLC and LCNEC and may help identify potential therapeutic targets.


Assuntos
Carcinoma de Células Grandes/genética , Carcinoma Neuroendócrino/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Neoplasias Pulmonares/genética , Proteômica , Carcinoma de Pequenas Células do Pulmão/genética , Idoso , Carcinoma de Células Grandes/metabolismo , Carcinoma de Células Grandes/patologia , Carcinoma Neuroendócrino/metabolismo , Carcinoma Neuroendócrino/patologia , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Mapeamento de Interação de Proteínas , Carcinoma de Pequenas Células do Pulmão/metabolismo , Carcinoma de Pequenas Células do Pulmão/patologia
11.
JA Clin Rep ; 4(1): 15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29457124

RESUMO

PURPOSE: The placement of a pulmonary artery catheter sometimes needs long time by observing the pressure wave, and several factors have been reported to hinder the placement. In the present study, we examined whether enlargement of the aortic root is associated with longer time for the placement. METHOD: We examined the time required for the catheter placement. The catheter placement time was defined as the duration of time required for the catheter to float from the CVP position to the pulmonary artery. The catheter placement was performed by one experienced physician. We examined the following factors on the catheter placement time: the patient's age, height, weight, cardiothoracic ratio, tricuspid regurgitation, ejection fraction and the diameter of aortic annulus, sinus of Valsalva, sinotubular junction, and proximal ascending aorta. These diameter values were divided by body surface area (BSA) to equalize among different physical sizes. The data were analyzed by multiple linear regression analysis after univariate analysis. RESULTS: The univariate analysis showed that ejection fraction and aortic annulus/BSA, sinus of Valsalva/BSA, and sinotubular junction/BSA correlated with the catheter placement time (P = 0.079, 0.030, 0.029, and 0.025, respectively). Since the three aortic root values correlated with each other, we chose the sinotubular junction/BSA for the following multivariate analysis, because of the highest P value. The multivariate analysis showed that sinotubular junction/BSA had a significant positive association with the placement time (P = 0.048). CONCLUSION: The present study showed that enlargement of the aortic root is associated with long placement time of the catheter.

12.
Proteomics Clin Appl ; 12(6): e1800015, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29888431

RESUMO

PURPOSE: The molecular underpinnings that may prognosticate survival and increase our understanding of tumor development and progression are still poorly understood. This study aimed to define the molecular signatures for malignancy in small cell lung carcinoma (SCLC), which is known for its highly aggressive clinical features and poor prognosis. EXPERIMENTAL DESIGN: Using clinical specimens, the authors perform a comparative proteomic analysis of high-grade SCLCs and low-grade pulmonary carcinoid tumors (PCTs), both of which are types of neuroendocrine tumors. A label-free LC-MS-based quantitative proteomic analysis is applied to tumor cells laser-microdissected from their formalin-fixed paraffin-embedded (FFPE) tissues obtained from six patients each. RESULTS: Overall, 1991 proteins are identified from tumor cells in the FFPE tissues. Through the protein-protein interaction network analysis of 201 proteins significantly, the authors find that SCLC is functionally characterized by activation of molecular pathways for spliceosome, RNA transport, and DNA replication and cell cycle. Particularly, 11 proteins involved in tumor proliferation (MCM2, 4, 6, 7, and MSH2), metastasis (RCC2, CORO1C, CHD4, and IPO9), and cancer metabolism (PHGDH and TYMP) are identified as SCLC-specific proteins. Furthermore, their prognostic significances are demonstrated by online Kaplan-Meier survival analysis. CONCLUSIONS AND CLINICAL RELEVANCE: These clinical tissue proteomic approach for SCLC reveals the proteins associated with aggressiveness and poor prognosis. The identified SCLC-specific proteins represent potential therapeutic targets. Moreover, MCMs and PHGDH can be poor prognostic factors for lung cancer.


Assuntos
Tumor Carcinoide/genética , Neoplasias Pulmonares/genética , Proteínas de Neoplasias/genética , Carcinoma de Pequenas Células do Pulmão/genética , Tumor Carcinoide/diagnóstico , Tumor Carcinoide/patologia , Proliferação de Células/genética , Diagnóstico Diferencial , Intervalo Livre de Doença , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Neoplasias/classificação , Prognóstico , Proteômica , Carcinoma de Pequenas Células do Pulmão/diagnóstico , Carcinoma de Pequenas Células do Pulmão/patologia
13.
JA Clin Rep ; 3(1): 63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29457106

RESUMO

BACKGROUND: Coronary artery to pulmonary artery fistula is an unusual vascular anomaly, and the shunt ratio of this fistula is usually small. CASE PRESENTATION: We report anesthetic management of a 55-year-old female with annuloaortic ectasia, aortic valve regurgitation, and coronary artery to pulmonary artery fistula undergoing radical repair. We calculated the left-to-right shunt ratio after placement of a pulmonary artery catheter and found that the ratio was unexpectedly high. Thus, we explored the presence of another shunt by intraoperative transesophageal echocardiography and found patent ductus arteriosus undiagnosed before operation. CONCLUSIONS: A combination of a pulmonary artery catheter and transesophageal echocardiography is useful to explore the presence of another shunt, such as patent ductus arteriosus during anesthesia.

14.
Ann Card Anaesth ; 20(2): 141-144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28393771

RESUMO

BACKGROUND: The development of arrhythmias during placement of a pulmonary artery catheter (PAC) is common. AIMS: This study was designed to examine factors influencing development of ventricular arrhythmias in adult patients undergoing cardiovascular operations during the catheter placement. SETTINGS AND DESIGNS: Prospective, observational, cohort study. METHODS: We prospectively studied 174 patients undergoing cardiovascular operations. A PAC was inserted through the right internal jugular vein by staff anesthesiologists. Electrocardiography tracings were recorded as the catheter was advanced from the right atrium to the pulmonary artery. Arrhythmias were classified as absent, single, or multiple (two or more consecutive) ventricular arrhythmias. We examined risk factors to produce ventricular arrhythmias during the placement. STATISTICAL ANALYSIS: The data were analyzed using logistic regression analysis to assess factors for the occurrence of ventricular arrhythmias after univariate analyses. RESULTS: Ventricular arrhythmias (single and multiple) occurred in 149 patients (85.6%) and multiple arrhythmias were observed in 78 patients (44.8%). There were no factors to facilitate the ventricular arrhythmias (single and multiple), whereas it showed that valvular diseases (P = 0.049) and the placement time (P < 0.001) are significant factors to produce multiple arrhythmias. CONCLUSION: Both valvular diseases and long placement time were significant risk factors to produce multiple ventricular arrhythmias during placement of a PAC.


Assuntos
Arritmias Cardíacas/etiologia , Cateterismo de Swan-Ganz/efeitos adversos , Artéria Pulmonar , Idoso , Arritmias Cardíacas/diagnóstico por imagem , Arritmias Cardíacas/fisiopatologia , Estudos de Coortes , Eletrocardiografia/métodos , Feminino , Coração/diagnóstico por imagem , Coração/fisiopatologia , Humanos , Masculino , Estudos Prospectivos , Fatores de Risco
15.
Viruses ; 9(9)2017 08 28.
Artigo em Inglês | MEDLINE | ID: mdl-28846635

RESUMO

Apoptosis is a type of programmed cell death that regulates cellular homeostasis by removing damaged or unnecessary cells. Its importance in host defenses is highlighted by the observation that many viruses evade, obstruct, or subvert apoptosis, thereby blunting the host immune response. Infection with Flaviviruses such as Japanese encephalitis virus (JEV), Dengue virus (DENV) and West Nile virus (WNV) has been shown to activate several signaling pathways such as endoplasmic reticulum (ER)-stress and AKT/PI3K pathway, resulting in activation or suppression of apoptosis in virus-infected cells. On the other hands, expression of some viral proteins induces or protects apoptosis. There is a discrepancy between induction and suppression of apoptosis during flavivirus infection because the experimental situation may be different, and strong links between apoptosis and other types of cell death such as necrosis may make it more difficult. In this paper, we review the effects of apoptosis on viral propagation and pathogenesis during infection with flaviviruses.


Assuntos
Apoptose/fisiologia , Infecções por Flavivirus/imunologia , Infecções por Flavivirus/metabolismo , Flavivirus/imunologia , Flavivirus/fisiologia , Animais , Morte Celular/imunologia , Morte Celular/fisiologia , Sobrevivência Celular , Vírus da Dengue/imunologia , Vírus da Dengue/fisiologia , Vírus da Encefalite Japonesa (Espécie)/imunologia , Vírus da Encefalite Japonesa (Espécie)/fisiologia , Retículo Endoplasmático/virologia , Interações Hospedeiro-Patógeno/imunologia , Interações Hospedeiro-Patógeno/fisiologia , Humanos , Estágios do Ciclo de Vida , Linfoma de Células B , Neoplasias/terapia , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais , Estresse Fisiológico , Vírus do Nilo Ocidental/imunologia , Vírus do Nilo Ocidental/fisiologia
16.
Ann Thorac Surg ; 102(2): 556-63, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27130251

RESUMO

BACKGROUND: Phosphatidylinositol 3-kinase is involved in myocardial function, including contractility. To date, myocardial regulation by phosphatidylinositol 3-kinase after brain death has not been investigated. The present study using a brain death model was designed to examine the role of phosphatidylinositol 3-kinase in myocardial function after brain death. METHODS: After anesthesia with sevoflurane, a Fogarty catheter was placed intracranially for induction of brain death. A conductance catheter was inserted into the left ventricle for measurement of myocardial function. Rats were assigned to the following groups: one group undergoing sham operation (with catheter placement but no brain death introduction); one group receiving saline before brain death; and one group receiving wortmannin, an inhibitor of phosphatidylinositol 3-kinase, before brain death. Various measurements, including mean blood pressure, heart rate, maximal rate of rise of left ventricular pressure, and ejection fraction, were obtained every 30 minutes for 6 hours after brain death. The phosphorylation status of Akt and phospholamban was determined 360 minutes after brain death. RESULTS: After induction of brain death, rats showed significant decreases in blood pressure, maximal rate of rise of left ventricular pressure, and ejection fraction. Inhibition of phosphatidylinositol 3-kinase using wortmannin significantly improved these measurements, resulting in increased survival. Western blot analysis demonstrated that brain death increased Akt phosphorylation and decreased phospholamban phosphorylation; these effects were abolished by wortmannin. CONCLUSIONS: Inhibition of phosphatidylinositol 3-kinase prevented myocardial dysfunction after brain death in association with inhibition of the decrease in phosphorylation of myocardial phospholamban, characteristic of brain death.


Assuntos
Morte Encefálica , Cálcio/metabolismo , Contração Miocárdica/fisiologia , Traumatismo por Reperfusão Miocárdica/metabolismo , Miocárdio/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Animais , Sinalização do Cálcio , Modelos Animais de Doenças , Masculino , Traumatismo por Reperfusão Miocárdica/etiologia , Fosforilação , Ratos , Ratos Sprague-Dawley
17.
Biomed Res Int ; 2015: 575474, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25654113

RESUMO

The present study using brain death model of rats was designed to examine whether prophylactic administration of volatile anesthetics and propofol prevent the epinephrine-induced arrhythmias. A Fogarty catheter was placed intracranially for induction of brain death. After brain death, the rats were randomly assigned to five groups: the control group (no anesthetics), the sevoflurane group (0.8%), the isoflurane group (0.5%), the halothane group (0.3%), and the propofol group (195 µg·kg(-1) ·min(-1)). These anesthetics were about 30% of ED50 of each anesthetic. The arrhythmogenic dose of epinephrine was determined in each anesthetic group. In addition, we examined left ventricular levels of connexin 43 phosphorylation 30 min after administration of each anesthetic with Western blot analysis. The arrhythmogenic dose of epinephrine in the sevoflurane group was significantly higher than that in the control group, while the arrhythmogenic dose of epinephrine in any other anesthetic group was not different. On the other hand, the ratio of phosphorylated-connexin 43/total connexin 43 was also similar among the study groups. Thus, prophylactic administration of subanesthetic dose of sevoflurane is effective in preventing epinephrine-induced arrhythmias after brain death, but phosphorylation of connexin is not involved in the antiarrhythmic property of sevoflurane.


Assuntos
Anestésicos/uso terapêutico , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/prevenção & controle , Morte Encefálica/patologia , Animais , Arritmias Cardíacas/fisiopatologia , Western Blotting , Morte Encefálica/fisiopatologia , Conexina 43/metabolismo , Relação Dose-Resposta a Droga , Epinefrina , Hemodinâmica , Masculino , Ratos Sprague-Dawley
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