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1.
Entropy (Basel) ; 24(4)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35455136

RESUMO

Cardiac autonomic neuropathy (CAN) is a common complication of diabetes mellitus, and can be assessed using heart rate variability (HRV) and the correlations between systolic blood pressure (SBP) and ECG R-R intervals (RRIs), namely baroreflex sensitivity (BRS). In this study, we propose a novel parameter for the nonlinear association between SBP and RRIs based on multiscale cross-approximate entropy (MS-CXApEn). Sixteen male adult Wistar Kyoto rats were equally divided into two groups: streptozotocin-induced diabetes and age-matched controls. RRIs and SBP were acquired in control rats and the diabetic rats at the onset of hyperglycemia and insulin-treated euglycemia to determine HRV by the ratio of low-frequency to high-frequency power (LF/HF) and Poincaré plot as SSR (SD1/SD2), BRS, and MS-CXApEn. SSR and BRS were not significantly different among the three groups. The LF/HF was significantly higher in the hyperglycemic diabetics than those in the controls and euglycemic diabetic rats. MS-CXApEn was higher in the diabetic hyperglycemic rats than the control rats from scales 2 to 10, and approached the values of controls in diabetic euglycemic rats at scales 9 and 10. Conclusions: We propose MS-CXApEn as a novel parameter to quantify the dynamic nonlinear interactions between SBP and RRIs that reveals more apparent changes in early diabetic rats. Furthermore, changes in this parameter were related to correction of hyperglycemia and could be useful for detecting and assessing CAN in early diabetes.

2.
Cell Physiol Biochem ; 46(3): 1252-1262, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29672298

RESUMO

BACKGROUND/AIMS: Intermittent hypoxia (IH) has been shown to exert preconditioning-like cardioprotective effects. It also has been reported that IH preserves intracellular pH (pHi) during ischemia and protects cardiomyocytes against ischemic reperfusion injury. However, the exact mechanism is still unclear. METHODS: In this study, we used proton indicator BCECF-AM to analyze the rate of pHi recovery from acidosis in the IH model of rat neonatal cardiomyocytes. Neonatal cardiomyocytes were first treated with repetitive hypoxia-normoxia cycles for 1-4 days. Cells were then acid loaded with NH4Cl, and the rate of pHi recovery from acidosis was measured. RESULTS: We found that the pHi recovery rate from acidosis was much slower in the IH group than in the room air (RA) group. When we treated cardiomyocytes with Na+-H+ exchange (NHE) inhibitors (Amiloride and HOE642) or Na+-free Tyrode solution during the recovery, there was no difference between RA and IH groups. We also found intracellular Na+ concentration ([Na+]i) significantly increased after IH exposure for 4 days. However, the phenomenon could be abolished by pretreatment with ROS inhibitors (SOD and phenanathroline), intracellular calcium chelator or Na+-Ca2+ exchange (NCX) inhibitor. Furthermore, the pHi recovery rate from acidosis became faster in the IH group than in the RA group when inhibition of NCX activity. CONCLUSIONS: These results suggest that IH would induce the elevation of ROS production. ROS then activates Ca2+-efflux mode of NCX and results in intracellular Na+ accumulation. The rise of [Na+]i further inhibits the activity of NHE-mediated acid extrusion and retards the rate of pHi recovery from acidosis during IH.


Assuntos
Hipóxia Celular , Trocador de Sódio e Cálcio/metabolismo , Sódio/metabolismo , Amilorida/farmacologia , Animais , Células Cultivadas , Feminino , Guanidinas/farmacologia , Concentração de Íons de Hidrogênio , Masculino , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Proteína Quinase C/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Trocador de Sódio e Cálcio/antagonistas & inibidores , Sulfonas/farmacologia , Superóxido Dismutase/metabolismo
3.
Acta Cardiol Sin ; 30(2): 151-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27122782

RESUMO

BACKGROUND: Infective endocarditis (IE) is a common and potentially serious disease. Although it is an illness that affects populations around the world, narrower descriptions of this disease as it impacts specific regions are uncommon. We analyzed the clinical characteristics of IE patients from two eastern counties in Taiwan and studied the relationship between the isolated pathogens and clinical outcomes in these patients. METHODS: This is a retrospective chart review study which enrolled patients who received services between January 2007 and December 2010. Subsequent to chart review, IE was confirmed in a total of 55 patients by the modified Duke criteria. RESULTS: Of these patients, 17 (31%) had previous traumatic open skin wounds. Pre-existing cardiac abnormalities were found in 47 (85%) patients, 28 of whom had valvular abnormalities. Staphylococcus aureus was isolated from the blood as the leading pathogen in 25 (45%) patients (including 23 methicillin-sensitive and 2 methicillin-resistant). Septic emboli and shock occurred in 27 (49%) of 55 patients; surgery was performed on 11 (20%) of those patients, and 4 (36%) of them died post-operatively. The total in-hospital mortality rate was 40% (n = 22). Staphylococcus aureus infection was associated with significantly higher complication and mortality rate than non-Staphylococcus aureus infection (59% vs. 41% and 64% vs. 36%, respectively; p < 0.05). In addition, patients with complications had a very high mortality rate (81.5%). CONCLUSIONS: We found that Staphylococcus aureus was the most common pathogen of IE in Eastern Taiwan, and was associated with higher rates of morbidities and mortality. KEY WORDS: Infective endocarditis; Septic shock; Staphylococcus aureus; Systemic embolization.

4.
Sci Rep ; 14(1): 8892, 2024 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632335

RESUMO

There is a lack of studies that concurrently differentiate the effect of the holiday season from the weekend effect on mortality risk in patients with acute myocardial infarction (AMI). We evaluated the mortality risk among patients admitted with AMI who underwent percutaneous coronary intervention, using data from the Taiwan National Health Insurance Research Database. Adult AMI patients admitted during January and February between 2013 and 2020 were enrolled and classified into the holiday season (using the Chinese New Year holiday seasons as an indicator) (n = 1729), weekend (n = 4725), and weekday (n = 14,583) groups according to the first day of admission. A multivariable logistic regression model was used to assess the risk. With the weekday group or the weekend group as the reference, the holiday season group did not have increased risks of in-hospital mortality (adjusted odds ratio [aOR] 1.15; 95% confidence intervals [CI] 0.93-1.42 or aOR 1.23; 95% CI 0.96-1.56) and 7-day mortality (aOR 1.20; 95% CI 0.90-1.58 or aOR 1.24; 95% CI 0.90-1.70). Stratified and subgroup analyses showed similar trends. We conclude that holiday season-initiated admissions were not associated with higher mortality risks in AMI admission cases than weekday or weekend admissions.


Assuntos
Infarto do Miocárdio , Intervenção Coronária Percutânea , Adulto , Humanos , Férias e Feriados , Taiwan , Fatores de Tempo , Fatores de Risco , Mortalidade Hospitalar , Admissão do Paciente , Estudos Retrospectivos
5.
Front Nutr ; 9: 807810, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35399690

RESUMO

Background: Systematic inflammation and lipid profiles are two major therapeutic targets for cardiovascular diseases. The effect of a nutritionally balanced vegan diet on systematic inflammation and lipoprotein subclass awaits further examination. Objective: To investigate the change in novel and traditional cardiometabolic risk factors before and after a dietitian-led vegan program, and to test the bioavailability of vitamin B12 in Taiwanese purple laver as part of a vegan diet. Design: A one-arm pilot intervention study. Participants/Setting: Nine patients with dyslipidemia participated in this 12-week vegan program. Main Outcome Measures: Nuclear Magnetic Resonance (NMR) detected GlycA signals (systematic inflammation) and lipoprotein subclass (atherogenicity); trimethylamine N-oxide (TMAO); and other cardiometabolic risk factors. Statistical Analyses Performed: Wilcoxon signed-rank test. Results: In this 12-week vegan intervention emphasizing whole foods, systematic inflammation improved as indicated by a reduction in GlycA (median: -23 µmol/L, p = 0.01). LDL-c (low-density lipoprotein cholesterol) (median -24 mg/dl, p = 0.04) and LDL-p (low-density lipoprotein particles) (median -75 nmol/L, p = 0.02) both decreased significantly. VLDL (very-low-density lipoprotein) and chylomicron particles showed a decreasing trend (-23.6 nmol/L, p = 0.05). Without caloric restriction, body mass index (BMI) (-0.7 kg/m2, p = 0.03), waist circumferences (-2.0 cm, p < 0.001), HbA1c (-0.2%, p = 0.02), and (HOMA-IR) homeostatic model assessment for insulin resistance (-0.7, p = 0.04) have all improved. The change in the TMAO and vitamin B12 status as measured by holo-transcobalamin appeared to depend on baseline diets, TMAO, and vitamin B12 status. Conclusions: A dietitian-led vegan program may improve systematic inflammation and other novel and traditional cardiometabolic risk factors in high-risk individuals.

6.
Medicine (Baltimore) ; 100(34): e27080, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34449509

RESUMO

RATIONALE: Peripartum cardiomyopathy (PPCM) is a rare and sometimes fatal systolic heart failure that affects women during late pregnancy or the early postpartum period. Heart failure symptoms can mimic the physiological changes of normal pregnancy, and the diagnosis is based on echocardiography. PATIENT CONCERNS: A 38-year-old multiparous woman with a history of cervical incompetence underwent cervical cerclage and received tocolysis for 100 days. DIAGNOSES: She delivered vaginally at 37 weeks of gestation but developed postpartum decompensated acute heart failure with low left ventricular ejection fraction (LVEF: 34%) and was diagnosed with PPCM. INTERVENTIONS: She received standard therapy for acute heart failure. OUTCOMES: The patient's pulmonary edema cleared, and she was fully ambulatory 6 days after admission. A follow-up echocardiogram 3 months later demonstrated recovery of LVEF to 66%. LESSONS: Prolonged tocolysis may contribute to cardiomyopathy and should be used with caution. PPCM management requires standard treatments for acute heart failure with modifications for fetal safety.


Assuntos
Cardiomiopatias/etiologia , Período Periparto , Tocólise/efeitos adversos , Adulto , Ecocardiografia , Feminino , Humanos , Gravidez
7.
Neurology ; 94(11): e1112-e1121, 2020 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-32102976

RESUMO

OBJECTIVE: To determine how a vegetarian diet affects stroke incidence in 2 prospective cohorts and to explore whether the association is modified by dietary vitamin B12 intake. METHODS: Participants without stroke in the Tzu Chi Health Study (cohort 1, n = 5,050, recruited in 2007-2009) and the Tzu Chi Vegetarian Study (cohort 2, n = 8,302, recruited in 2005) were followed until the end of 2014. Diet was assessed through food frequency questionnaires in both cohorts at baseline. Stroke events and baseline comorbidities were identified through the National Health Insurance Research Database. A subgroup of 1,528 participants in cohort 1 were assessed for serum homocysteine, vitamin B12, and folate. Associations between vegetarian diet and stroke incidences were estimated by Cox regression with age as time scale, adjusted for sex, education, smoking, alcohol, physical activities, body mass index (only in cohort 1), hypertension, diabetes, dyslipidemia, and ischemic heart diseases. RESULTS: Vegetarians had lower serum vitamin B12 and higher folate and homocysteine than nonvegetarians. In cohort 1, 54 events occurred in 30,797 person-years follow-up. Vegetarians (vs nonvegetarians) experienced lower risk of ischemic stroke (hazard ratio [HR], 0.26; 95% confidence interval [CI], 0.08-0.88). In cohort 2, 121 events occurred in 76,797 person-years follow-up. Vegetarians (vs nonvegetarians) experienced lower risk of overall stroke (HR, 0.52; 95% CI, 0.33-0.82), ischemic stroke (HR, 0.41; 95% CI, 0.19-0.88), and hemorrhagic stroke (HR, 034; 95% CI, 0.12-1.00). Our explorative analysis showed that vitamin B12 intake may modify the association between vegetarian diet and overall stroke (p interaction = 0.046). CONCLUSION: Taiwanese vegetarian diet is associated with a lower risk of ischemic and hemorrhagic strokes.


Assuntos
Dieta Vegetariana , Acidente Vascular Cerebral/epidemiologia , Adulto , Idoso , Estudos de Coortes , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Taiwan/epidemiologia , Vitamina B 12
8.
J Neurosci ; 28(7): 1546-56, 2008 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-18272676

RESUMO

The NMDA receptor opens in response to binding of NMDA and glycine. However, it remains unclear where and how gating of the NMDA receptor pore is accomplished. We show that different point mutations between S645 and I655 (thus including the highly conserved SYTANLAAF motif) of M3c in NR2B lead to constitutively open channels. The current through these constitutively open channels are readily blocked by external Mg2+ and MK-801 [(+)-5-methyl-10,11-dihydro-5H-dibenzo [a,d] cyclohepten-5,10-imine maleate]. Also, the open-channel blocker MK-801 can no longer be trapped in these channels when NMDA and glycine are washed off. Moreover, M3c residues at or below A651(NR2B, A7 in SYTANLAAF) react with external methanethiosulfonate (MTS) reagents approximately 500 to 1000-fold faster in the presence than in the absence of agonists NMDA and glycine. In fact, the MTS modification rate shows exactly the same NMDA concentration dependence as channel activation. In contrast, those residues external to A651 are always modified with similar kinetics whether NMDA and glycine are present or not. Interestingly, MTS modification of A651C(NR2B) holds the channel constitutively open. Mutations of A651(NR2B) into arginine, tryptophan, or phenylalanine, and similar mutations of the corresponding A652 in NR1 also lead to constitutively open channels. Double-mutant cycle analysis further shows that the effects of A652(NR1) and A651(NR2B) mutations are evidently non-additive (i.e., cooperative) if mutated into residues with large side chains or with compensatory charges [e.g., A652E(NR1)+A651R(NR2B)]. The side chain of A7 thus plays a determinant role in the intersubunit distance at this level, which is directly responsible for the activation gate and activation-deactivation gating of the NMDA receptor.


Assuntos
Regulação da Expressão Gênica , Ativação do Canal Iônico/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Animais , Maleato de Dizocilpina/metabolismo , Técnicas In Vitro , Ativação do Canal Iônico/fisiologia , Mutagênese Sítio-Dirigida , Oócitos/metabolismo , Técnicas de Patch-Clamp , Mutação Puntual , Ratos , Receptores de N-Metil-D-Aspartato/agonistas , Receptores de N-Metil-D-Aspartato/genética , Xenopus
9.
Cells ; 8(6)2019 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-31181855

RESUMO

It has been documented that reactive oxygen species (ROS) contribute to oxidative stress, leading to diseases such as ischemic heart disease. Recently, increasing evidence has indicated that short-term intermittent hypoxia (IH), similar to ischemia preconditioning, could yield cardioprotection. However, the underlying mechanism for the IH-induced cardioprotective effect remains unclear. The aim of this study was to determine whether IH exposure can enhance antioxidant capacity, which contributes to cardioprotection against oxidative stress and ischemia/reperfusion (I/R) injury in cardiomyocytes. Primary rat neonatal cardiomyocytes were cultured in IH condition with an oscillating O2 concentration between 20% and 5% every 30 min. An MTT assay was conducted to examine the cell viability. Annexin V-FITC and SYTOX green fluorescent intensity and caspase 3 activity were detected to analyze the cell death. Fluorescent images for DCFDA, Fura-2, Rhod-2, and TMRM were acquired to analyze the ROS, cytosol Ca2+, mitochondrial Ca2+, and mitochondrial membrane potential, respectively. RT-PCR, immunocytofluorescence staining, and antioxidant activity assay were conducted to detect the expression of antioxidant enzymes. Our results show that IH induced slight increases of O2-· and protected cardiomyocytes against H2O2- and I/R-induced cell death. Moreover, H2O2-induced Ca2+ imbalance and mitochondrial membrane depolarization were attenuated by IH, which also reduced the I/R-induced Ca2+ overload. Furthermore, treatment with IH increased the expression of Cu/Zn SOD and Mn SOD, the total antioxidant capacity, and the activity of catalase. Blockade of the IH-increased ROS production abolished the protective effects of IH on the Ca2+ homeostasis and antioxidant defense capacity. Taken together, our findings suggest that IH protected the cardiomyocytes against H2O2- and I/R-induced oxidative stress and cell death through maintaining Ca2+ homeostasis as well as the mitochondrial membrane potential, and upregulation of antioxidant enzymes.


Assuntos
Apoptose , Cálcio/metabolismo , Hipóxia Celular , Mitocôndrias/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Antioxidantes/metabolismo , Apoptose/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/patologia , Miócitos Cardíacos/citologia , Miócitos Cardíacos/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
10.
Front Physiol ; 10: 995, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31447690

RESUMO

Intermittent hypoxia (IH), characterized as cyclic episodes of short-period hypoxia followed by normoxia, occurs in many physiological and pathophysiological conditions such as pregnancy, athlete, obstructive sleep apnea, and asthma. Hypoxia can induce autophagy, which is activated in response to protein aggregates, in the proteotoxic forms of cardiac diseases. Previous studies suggested that autophagy can protect cells by avoiding accumulation of misfolded proteins, which can be generated in response to ischemia/reperfusion (I/R) injury. The objective of the present study was to determine whether IH-induced autophagy can attenuate endoplasmic reticulum (ER) stress and cell death. In this study, H9c2 cell line, rat primary cultured cardiomyocytes, and C57BL/6 male mice underwent IH with an oscillating O2 concentration between 4 and 20% every 30 min for 1-4 days in an incubator. The levels of LC3, an autophagy indicator protein and CHOP and GRP78 (ER stress-related proteins) were measured by Western blotting analyses. Our data demonstrated that the autophagy-related proteins were upregulated in days 1-3, while the ER stress-related proteins were downregulated on the second day after IH. Treatment with H2O2 (100 µM) for 24 h caused ER stress and increased the level of ER stress-related proteins, and these effects were abolished by pre-treatment with IH condition. In response to the autophagy inhibitor, the level of ER stress-related proteins was upregulated again. Taken together, our data suggested that IH could increase myocardial autophagy as an adaptive response to prevent the ER stress and apoptosis.

11.
J Med Chem ; 51(6): 1534-45, 2008 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-18311896

RESUMO

The antiepileptic effect of felbamate (FBM) is ascribable to gating modification of NMDA receptors. Using site-directed mutagenesis and electrophysiological studies, we found that single-point mutations of four pairs of homologous residues in the external vestibule of the receptor pore, namely V644(NR1)-L643(NR2B) (the two inner pairs) and T648(NR1)-T647(NR2B) (the two outer pairs), significantly decrease FBM binding. Moreover, double mutations involving either the inner or the outer pair always show cooperative (nonadditive) effects on FBM binding, whereas double mutations involving both inner and outer pairs always show additive (noncooperative) effects. Most interestingly, triple mutations of any three of the four critical residues essentially abolish the effect of FBM. These findings indicate that T648(NR1)/T647(NR2B) and V644(NR1)/L643(NR2B) act cooperatively to contribute directly to the "outer binding region" and "inner binding region" in the FBM binding site, respectively. The outer and inner binding regions, however, seem to contribute independently to FBM binding. We conclude that residues L643 and T647 in NR2B as well as homologous residues V644 and T648 in NR1 are the major, and very likely the exclusive, molecular determinants constituting the FBM binding site in the NMDA receptor.


Assuntos
Anticonvulsivantes/farmacologia , Fenilcarbamatos/farmacologia , Propilenoglicóis/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Animais , Anticonvulsivantes/química , Sítios de Ligação/efeitos dos fármacos , Ligação Competitiva/efeitos dos fármacos , Ligação Competitiva/genética , Células Cultivadas , Clonagem Molecular , Relação Dose-Resposta a Droga , Eletrofisiologia , Felbamato , Regulação da Expressão Gênica/efeitos dos fármacos , Ativação do Canal Iônico/efeitos dos fármacos , Ativação do Canal Iônico/genética , Modelos Moleculares , Estrutura Molecular , Mutagênese Sítio-Dirigida , Oócitos/efeitos dos fármacos , Oócitos/metabolismo , Fenilcarbamatos/química , Propilenoglicóis/química , Ratos , Receptores de N-Metil-D-Aspartato/química , Receptores de N-Metil-D-Aspartato/genética , Relação Estrutura-Atividade , Xenopus
12.
Vascul Pharmacol ; 48(2-3): 122-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18295548

RESUMO

In the present study, we determined the vascular functions using a canine model of isolated intestinal segment perfused with constant flow. The effects of an NO donor, S-nitroso-N-acetylpenicillamine (SNAP) and an NO synthase inhibitor, N(omega)-nitro-l-arginine methyl ester (l-NAME) on the vascular factors (resistance, exchange and capacitance) were evaluated. In condition of venous pressure at 0 mmHg, we determined and calculated arterial pressure (Pa) and capillary pressure (Pc). Vascular factors including total, pre- and post-capillary resistance (R(T), Ra and Rv), vascular compliance (VC) and capillary filtration coefficient (K(fc)) were obtained. SNAP at doses 10(-6) to 10(-4) mol/l produced vasodilatory effects. It dose-dependently reduced the Pa, Pc, R(T) and Ra, as well as the Ra/Rv ratio. The Rv was slightly decreased. This agent increased the vascular capacity, VC and K(fc). NO inhibition with l-NAME (10(-6) to 10(-4) mol/l) produced the opposite effects. The vasoconstrictory effects of l-NAME increased Pa, Pc, R(T) and Ra as well as the Ra/Rv ratio. It slightly raised the Rv. l-NAME reduced the vascular capacity, VC and K(fc). The effects of l-NAME were also dose-dependent. This study has provided a detailed data of the vasodilatory and vasoconstrictory effects NO donation and inhibition on vascular factors in the intestinal vasculature.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Íleo/irrigação sanguínea , Doadores de Óxido Nítrico/farmacologia , Óxido Nítrico Sintase/antagonistas & inibidores , Resistência Vascular/efeitos dos fármacos , Vasoconstritores/farmacologia , Vasodilatadores/farmacologia , Animais , Pressão Sanguínea/efeitos dos fármacos , Capilares/efeitos dos fármacos , Capilares/enzimologia , Cães , Relação Dose-Resposta a Droga , Capacitância Elétrica , Técnicas In Vitro , Artérias Mesentéricas/efeitos dos fármacos , Artérias Mesentéricas/enzimologia , Veias Mesentéricas/efeitos dos fármacos , Veias Mesentéricas/enzimologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Perfusão , S-Nitroso-N-Acetilpenicilamina/farmacologia , Fatores de Tempo , Vasoconstrição/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Pressão Venosa/efeitos dos fármacos
13.
Chin J Physiol ; 50(2): 43-50, 2007 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-17608140

RESUMO

Nitric oxide (NO) is an important gas molecule that plays a pivotal role in physiology and pathology in various systems. Our laboratory has been working on the hypertensive cardiovascular disorders and pulmonary edema for more than 30 years. In this brief review article, we have described the role of NO in hypertension, pulmonary disorders, sepsis, and to some extent, the endothelial factors on the arterial baroreceptors and cerebral blood flow. Our studies indicate that the vasodilatory effects of endogenous NO act primarily on the small resistance vessels. The large conduit vessels are less affected. In contrast to the earlier work suggesting that NO or endothelial function is impaired in hypertension, we have provided evidence to indicate that the NO release or function is enhanced in rats with hypertension. Chronic NO deprivation in rats with spontaneous hypertension facilitates the progression of hypertension to malignant phase with marked functional and structural changes in blood vessels of various organs. In most studies using isolated perfused lungs, our results show that NO exerts toxic effect on the lung injury following ischemia/reperfusion, air embolism, endotoxemia and hypoxia. Recent clinical investigations have revealed that the inducible NO synthase (iNOS) expression was increased in patients with enterovirus and other infections, suggesting a detrimental role of iNOS and NO in the acute lung injury. In this review article, we have also provided the experiences, results and stories in our laboratory during a relatively long period investigating the good and bad sides of NO on the cardiopulmonary functions. The purposes are two-fold: first, to share the experience and stories for scientific and educational purposes; and second, to encourage young investigators to continue work on many questions yet unanswered.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Óxido Nítrico/fisiologia , Circulação Pulmonar/fisiologia , Animais , Endotélio Vascular/fisiologia , Humanos , Hipertensão/fisiopatologia , Edema Pulmonar/fisiopatologia , Ratos , Ratos Endogâmicos SHR , Sepse/fisiopatologia , Vasodilatação/fisiologia
14.
Ci Ji Yi Xue Za Zhi ; 29(2): 121-124, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28757779

RESUMO

Symmetrical peripheral gangrene (SPG) is characterized by sudden onset of peripheral, frequently symmetrical, gangrene in the absence of major vascular occlusive disease. We report a case of four limb SPG caused by septic shock with disseminated intravascular coagulation (DIC) that had been treated with inotropes. This case shows that SPG may be present as a complication of sepsis due to systematic derangement that affects a wide range of organ systems, including coagulation and microcirculation. Early recognition and prompt management of sepsis and optimization of the process of weaning off the inotropes at the earliest opportunity are necessary to avoid SPG.

15.
Life Sci ; 78(2): 164-73, 2005 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-16125730

RESUMO

In the present study, we elucidated the possible role of hemodynamic parameters and chemical factors in the development of ventricular hypertrophy (VH) following chronic nitric oxide (NO) deprivation with Nomega-nitro-L-arginine methyl ester (L-NAME). Impedance spectral analysis was used to obtain the arterial hemodynamics including the steady and pulsatile components. Body weight (BW), left ventricular (LV) weight (LVW), LVW/BW ratio, LV collagen volume fraction (LVCVF), cyclic GMP, and nitrite/nitrate were measured. The extent of VH was evaluated by the LW/BW, total number, numerical density, and size of cardiomyocytes. Sprague-Dawley rats were given L-NAME 10, 20, and 40 mg/kg/day from the age of 10 to 18 weeks. Control and age-matched rats were given vehicle for the same period. Treatment of L-NAME for 8 weeks caused a dose-dependent increase in tail cuff pressure and a reduction in BW with increases in LVW, LVW/BW, number, numerical density, and size of myocytes. There was elevation of aortic pressure with decreases in cardiac output, and arterial compliance. The total peripheral resistance, characteristic impedance and pulse wave reflection were increased. Histological finding revealed severe myocardial hypertrophy and fibrosis with fibroblast infiltration. The LVCVF was increased, while LV cGMP and nitrite/nitrate were reduced in a dose-dependent manner. The results suggest that chronic NOS blockade causes hypertension, impairment of large vessel properties, and VH. The development of VH may result partly from the decreases in cGMP and nitrite/nitrate in the ventricle. Correlation analysis indicates that the extent of VH is equally related to the steady and pulsatile hemodynamics.


Assuntos
Artérias/fisiopatologia , Cardiomegalia/fisiopatologia , Hemodinâmica/fisiologia , Óxido Nítrico/fisiologia , Algoritmos , Animais , Peso Corporal/efeitos dos fármacos , Cardiomegalia/patologia , Contagem de Células , Colágeno/metabolismo , GMP Cíclico/metabolismo , Eletrocardiografia/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/patologia , NG-Nitroarginina Metil Éster/farmacologia , Nitratos/metabolismo , Óxido Nítrico Sintase Tipo III/antagonistas & inibidores , Tamanho do Órgão/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Função Ventricular Esquerda/efeitos dos fármacos , Função Ventricular Esquerda/fisiologia
16.
Chin J Physiol ; 48(1): 15-22, 2005 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-15973963

RESUMO

The purpose of this experiment was to explore long-term L-arginine administration on ventricular hypertrophy and cardiac fibrosis in spontaneously hypertensive rats (SHR) and normotensive Wistar Kyoto (WKY) rats. Twenty-four rats of each strain at eight wks of age were divided into two groups--one receiving L-arginine and the other vehicle for twelve wks. Arterial pressure (AP) and heart rate were monitored. At 20 wks of age, the rats' rings of thoracic aorta were isolated to record isometric tension. The study measured left ventricular weight (LVW), body weight (BW), left ventricular (LV) contents of cGMP, and collagen volume fraction (LVCVF). Histological examination of the LV tissue determined changes in cardiomyocytes. Administration of L-arginine did not alter the AP change in SHR, but reduced the AP in WKY after six wks. Our results showed a significantly higher LVW/BW ratio and LVCVF in vehicle-treated SHR compared to levels in corresponding WKY, whereas, the LV cGMP and nitrite/nitrate measurements were higher in vehicle-treated WKY than in SHR. L-Arginine treatment decreased LVW/BW ratio and LVCVF, while increasing the levels of LV cGMP and nitrite/nitrate only in SHR, consistent with histopathological examinations that showed L-arginine prevented cardiomyocytes from thickness and hypertrophy. Our results suggested that the mechanism of reduction in ventricular hypertrophy and fibrosis following long-term L-arginine administration in SHR may stem from increased myocardial nitric oxide-cGMP signaling, independent of AP and EDV of thoracic aorta.


Assuntos
Arginina/uso terapêutico , Cardiomegalia/prevenção & controle , Fibrose Endomiocárdica/prevenção & controle , Hipertensão/complicações , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/fisiologia , GMP Cíclico/análise , Frequência Cardíaca/efeitos dos fármacos , Óxido Nítrico/análise , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Sístole/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos
17.
Tex Heart Inst J ; 42(6): 554-7, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26664310

RESUMO

Anomalous origin of the left main coronary artery from the right sinus of Valsalva is extremely rare and can lead to sudden cardiac death. We report a case in which an 18-year-old college student collapsed immediately after a long-distance run of 10 km. After cardiopulmonary resuscitation and electrical shock for ventricular fibrillation, she experienced a return of spontaneous circulation. Cardiac catheterization and cardiac computed tomographic angiography revealed an unusually long intramural course of the left main coronary artery from the right sinus of Valsalva. The young woman underwent a successful unroofing operation for coronary artery correction. She remained asymptomatic upon exercise during 2.5 years of follow-up.


Assuntos
Anomalias dos Vasos Coronários/complicações , Morte Súbita Cardíaca/etiologia , Parada Cardíaca Extra-Hospitalar/etiologia , Corrida , Seio Aórtico/anormalidades , Adolescente , Cateterismo Cardíaco , Procedimentos Cirúrgicos Cardíacos , Reanimação Cardiopulmonar , Angiografia Coronária/métodos , Anomalias dos Vasos Coronários/diagnóstico , Anomalias dos Vasos Coronários/cirurgia , Morte Súbita Cardíaca/prevenção & controle , Cardioversão Elétrica , Eletrocardiografia , Feminino , Humanos , Tomografia Computadorizada Multidetectores , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia , Recuperação de Função Fisiológica , Seio Aórtico/diagnóstico por imagem , Seio Aórtico/cirurgia , Resultado do Tratamento
18.
Am J Med Sci ; 348(3): 210-4, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24736765

RESUMO

BACKGROUND: It has been shown that metabolic syndrome is associated with lower levels of plasma N-terminal pro-B-type natriuretic peptide (Nt-proBNP) in the general population. However, there is no study about the association between Nt-proBNP and metabolic syndrome in hypertensive patients. AIM: : To elucidate the relationship between Nt-proBNP and components of metabolic syndrome in hypertensive patients. METHODS: Fasting blood samples were obtained from 74 hypertensive patients in our institution. Plasma levels of Nt-proBNP and other biochemical data were measured. Metabolic syndrome and its components were defined using diagnostic criteria from the International Diabetes Federation. RESULTS: Forty-four hypertensive patients met the criteria for metabolic syndrome. We found that plasma Nt-proBNP levels were lower in hypertensive patients with metabolic syndrome attributable to inverse relationships between Nt-proBNP and albumin, triglyceride, insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and pancreatic ß-cell function (HOMA-ß). We further performed a multivariable linear regression analysis. The result showed that HOMA-IR is the independent predictor of plasma Nt-proBNP levels in hypertensive patients. CONCLUSIONS: Plasma Nt-proBNP levels are inversely associated with metabolic syndrome in hypertensive patients. HOMA-IR is the independent predictor of Nt-proBNP in hypertensive patients.


Assuntos
Hipertensão/sangue , Hipertensão/epidemiologia , Síndrome Metabólica/sangue , Síndrome Metabólica/epidemiologia , Peptídeo Natriurético Encefálico/sangue , Fragmentos de Peptídeos/sangue , Precursores de Proteínas/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Estudos Transversais , Feminino , Homeostase/fisiologia , Humanos , Hipertensão/diagnóstico , Masculino , Síndrome Metabólica/diagnóstico , Pessoa de Meia-Idade
19.
Am J Med Sci ; 346(5): 424-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23694925

RESUMO

Ancient neurilemoma is a rare variant of neurilemoma and can grow into a large tumor, which results in several symptoms. It is often misdiagnosed to be malignant neoplasm because of its histological features of nuclear atypia. The authors reported an 87-year-old woman presenting with progressive dyspnea and chronic cough for more than 1 year. Computed tomography of the chest showed a huge heterogeneous, paravertebral mass with focal calcification, arising from intervertebral foramen. The tumor was successfully resected by thoracotomy and pathology disclosed ancient neurilemoma.


Assuntos
Mesenquimoma/diagnóstico , Neurilemoma/diagnóstico , Neoplasias Torácicas/diagnóstico , Idoso de 80 Anos ou mais , Diagnóstico Diferencial , Feminino , Humanos , Mesenquimoma/patologia , Mesenquimoma/cirurgia , Neurilemoma/patologia , Neurilemoma/cirurgia , Neoplasias Torácicas/patologia , Neoplasias Torácicas/cirurgia , Toracotomia , Tomografia Computadorizada por Raios X , Resultado do Tratamento
20.
Intern Med ; 52(17): 1923-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23994984

RESUMO

Coronary artery fistulae that drain into the left ventricle are extremely rare, and even fewer cases of fistulae involving all three of the coronary arteries have so far been reported. We herein report a 64-year-old woman with a unique pattern of coronary artery-left ventricular fistulae that involved all three of the coronary arteries. The multiple fistulae presented in a diffuse plexus-like arrangement. The fistulae resulted in a diastolic volume overload of the left ventricle (left-to-left shunt), as well as "coronary steal" with the shunting of blood away from the myocardium since the fistulae represented the path of least resistance.


Assuntos
Anomalias dos Vasos Coronários/diagnóstico por imagem , Ventrículos do Coração/anormalidades , Ventrículos do Coração/diagnóstico por imagem , Microcirculação , Feminino , Humanos , Pessoa de Meia-Idade , Radiografia
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