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1.
Phys Med Biol ; 51(4): 845-54, 2006 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-16467582

RESUMO

Laser Doppler flowmetry (LDF) is a popular method for monitoring the microcirculation, but it does not provide absolute measurements. Instead, the mean flux response or energy distribution in the frequency domain is generally compared before and after stimulus. Using the heartbeat as a trigger, we investigated whether the relation between pressure and flux can be used to discriminate different microcirculatory conditions. We propose the following three pulsatile indices for evaluating the microcirculation condition from the normalized pressure and flux segment with a synchronized-averaging method: peak delay time (PDT), pressure rise time and flux rise time (FRT). The abdominal aortic blood pressure and renal cortex flux (RCF) signals were measured in spontaneously hypertensive rats (SHR) and Wistar Kyoto rats (WKY). The mean value of the RCF did not differ between SHR and WKY. However, the PDT was longer in SHR (87.14 +/- 5.54 ms, mean +/- SD) than in WKY (76.92 +/- 2.62 ms; p < 0.001). The FRT was also longer in SHR (66.56 +/- 1.98 ms) than in WKY (58.02 +/- 1.77 ms; p < 0.001). We propose that a new dimension for comparing the LDF signals, which the results from the present study show, can be used to discriminate RCF signals that cannot be discriminated using traditional methods.


Assuntos
Diagnóstico por Computador/métodos , Hipertensão/diagnóstico , Hipertensão/fisiopatologia , Fluxometria por Laser-Doppler/métodos , Microcirculação/fisiopatologia , Circulação Renal , Animais , Eletrocardiografia/métodos , Feminino , Masculino , Ratos , Ratos Wistar
2.
Cell Death Differ ; 11 Suppl 1: S97-107, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15002040

RESUMO

Recent evidence indicates that the decoy receptor 3 (DcR3) of the TNF receptor superfamily, which initially though prevents cytokine responses of FasL, LIGHT and TL1A by binding and neutralization, can modulate monocyte function through reverse signaling. We show in this work that DcR3 can induce osteoclast formation from human monocytes, murine RAW264.7 macrophages, and bone marrow cells. DcR3-differentiated cells exhibit characteristics unique for osteoclasts, including polynuclear giant morphology, bone resorption, TRAP, CD51/61, and MMP-9 expression. Consistent with the abrogation of osteoclastogenic effect of DcR3 by TNFR-Fc, DcR3 treatment can induce osteoclastogenic cytokine TNF-alpha release through ERK and p38 MAPK signaling pathways. We conclude that DcR3 via coupling reverse signaling of ERK and p38 MAPK and stimulating TNF-alpha synthesis is a critical regulator of osteoclast formation. This action of DcR3 might play an important role in significant osteoclastic activity in osteolytic bone metastases.


Assuntos
Diferenciação Celular/fisiologia , Glicoproteínas de Membrana/farmacologia , Monócitos/fisiologia , Osteoclastos/fisiologia , Fosfatase Ácida/genética , Fosfatase Ácida/metabolismo , Animais , Western Blotting , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Células da Medula Óssea/fisiologia , Reabsorção Óssea/metabolismo , Proteínas de Transporte/farmacologia , Diferenciação Celular/efeitos dos fármacos , Fusão Celular , Linhagem Celular , Citocinas/metabolismo , Citocinas/farmacologia , Dinoprostona/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Citometria de Fluxo , Expressão Gênica/efeitos dos fármacos , Humanos , Isoenzimas/genética , Isoenzimas/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Lipopolissacarídeos/farmacologia , MAP Quinase Quinase 4 , Fator Estimulador de Colônias de Macrófagos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/fisiologia , Metaloproteinase 9 da Matriz/genética , Glicoproteínas de Membrana/fisiologia , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Osteoclastos/citologia , Osteoclastos/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Ligante RANK , Ratos , Ratos Sprague-Dawley , Receptor Ativador de Fator Nuclear kappa-B , Receptores de Superfície Celular/fisiologia , Receptores do Fator de Necrose Tumoral , Membro 6b de Receptores do Fator de Necrose Tumoral , Receptores Tipo I de Fatores de Necrose Tumoral/metabolismo , Receptores de Vitronectina/metabolismo , Fosfatase Ácida Resistente a Tartarato , Fator de Necrose Tumoral alfa/metabolismo , Fator de Necrose Tumoral alfa/farmacologia
3.
Zhonghua Yi Xue Za Zhi (Taipei) ; 64(8): 469-73, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11720146

RESUMO

BACKGROUND: Aneurysms of the sinus of Valsalva (SVA) are uncommon congenital lesions. The clinical presentations vary from asymptomatic to progressive heart failure following rupture of the aneurysm into an adjacent cardiac chamber. Retrograde aortogram is the diagnostic tool of choice preoperatively. Recent studies have demonstrated that the SVA can be accurately diagnosed using transthoracic two-dimensional, and color Doppler flow mapping, even for surgical preparation without cardiac catheterization. We report our 5-year experience of transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) in the evaluation of SVA. METHODS: Eleven adult patients with SVA with or without rupture were studied using both TTE and TEE. All of the diagnoses were subsequently comfirmed by either cardiac catheterization or surgical findings. RESULTS: Aneurysms originated in the right coronary sinus (n = 9) and noncoronary sinus (n = 2); they ruptured into the right ventricle in 5 patients and the right atrium in 5 patients. An unruptured right SVA was noted in 1 patient. Both TTE and TEE could identify the site of the aneurysm, rupture sites, and the receiving chamber equally well. Co-existent cardiac lesions included 11 cases of valvular aortic regurgitation (mild in 7, moderate in 2 and severe in 2). Two cases of perimembranous type ventricular septal defect (VSD) and 6 cases of supracristal type VSD (including 1 case of tetraology of Fallot, 3 supracristal, 1 muscular and 1 subaortic) were noted. Three cases were complicated with valvular vegetations (1 aortic valve, 1 aortic and tricuspid valve and 1 aortic and pulmonic valve). One patient had patent ductus arteriosus and 2 patients had pulmonic valvular stenosis. CONCLUSIONS: TEE provides clearer definition for the detailed anatomy of the ruptured sac and co-existent cardiac lesions than TTE through high resolution and closer approach. We conclude that TEE is a powerful complementary diagnostic tool in the evaluation of patients with SVA. TEE also provides additionally useful information for guiding the surgical approach and for assessing the operative results even without cardiac catheterization.


Assuntos
Aneurisma/diagnóstico por imagem , Ecocardiografia Transesofagiana , Ecocardiografia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Seio Aórtico
4.
J Am Soc Echocardiogr ; 14(10): 1001-9, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11593205

RESUMO

BACKGROUND: The purpose of our study was to validate the ability of real-time 3-dimensional echocardiography (RT3D) to measure cardiac volume. METHODS: We studied 25 patients with various cardiac disorders who had a regular heart rhythm and a good precordial echocardiographic window. Each patient underwent complete transthoracic echocardiography (TTE), RT3D, and magnetic resonance imaging (MRI) studies. Left ventricular dimension was calculated from slices of the whole left ventricle obtained by 7 different equidistant azimuth tilts. Planimetry of the endocardial (for volume data) and epicardium (for mass data) surface was performed for each azimuth tilt. The left ventricular end-diastolic volume (LVEDV) and the left ventricular end-systolic volume (LVESV) were calculated. The cardiac mass data were derived with the formula (Epicardial volume - LVEDV) x 1.055. The parameters of LVEDV, LVESV, stroke volume, ejection fraction, and cardiac mass were compared with those derived from MRI. RESULTS: No statistically significant differences were found between the data from RT3D and MRI (P > or =.05). Good correlations were found between these two methods for left ventricle volume and mass measurements (r from 0.92 to 0.99). However, a weaker correlation was found with larger chamber sizes because extrapolation was necessary for the volume of myocardial segments that were not covered by the small sector angle. CONCLUSIONS: For data acquisition, RT3D is faster than either TTE or MRI. It is also better than MRI for measuring cardiac volume and mass. To improve results with larger cardiac chamber sizes, enlargement of the sector angle will be necessary.


Assuntos
Ecocardiografia Tridimensional , Cardiopatias/diagnóstico por imagem , Cardiopatias/fisiopatologia , Imageamento por Ressonância Magnética , Volume Sistólico , Função Ventricular Esquerda , Adulto , Ecocardiografia Tridimensional/métodos , Feminino , Cardiopatias/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Análise de Regressão , Fatores de Tempo , Remodelação Ventricular
5.
J Cardiovasc Electrophysiol ; 12(8): 887-92, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11513438

RESUMO

INTRODUCTION: Elimination of the initiating focus within the pulmonary vein (PV) using radiofrequency (RF) catheter ablation is a new treatment modality for treatment of drug-refractory atrial fibrillation. However, information on the long-term safety of RF ablation within the PV is limited. METHODS AND RESULTS: In 102 patients with drug-refractory atrial fibrillation and at least one initiating focus from the PV, series transesophageal echocardiography was performed to monitor the effect of RF ablation on the PV. There were 66 foci in the right upper PV and 65 foci in the left upper PV. Within 3 days of ablation, 26 of the ablated right upper PVs (39%) had increased peak Doppler flow velocity (mean 130+/-28 cm/sec, range 106 to 220), and 15 of the ablated left upper PVs (23%) had increased peak Doppler flow velocity (mean 140+/-39 cm/sec, range 105 to 219). Seven patients had increased peak Doppler flow velocity in both upper PVs. No factor (including age, sex, site of ablation, number of RF pulses, pulse duration, and temperature) could predict PV stenosis after RF ablation. Three patients with stenosis of both upper PVs experienced mild dyspnea on exertion, but only one had mild increase of pulmonary pressure. There was no significant change of peak and mean flow velocity and of PV diameter in sequential follow-up studies up to 16 (209+/-94 days) months. CONCLUSION: Focal PV stenosis is observed frequently after RF catheter ablation applied within the vein, but usually is without clinical significance. However, ablation within multiple PVs might cause pulmonary hypertension and should be considered a limiting factor in this procedure.


Assuntos
Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/cirurgia , Ablação por Cateter , Veias Pulmonares/fisiopatologia , Pneumopatia Veno-Oclusiva/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/complicações , Velocidade do Fluxo Sanguíneo/fisiologia , Ecocardiografia Transesofagiana , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Veias Pulmonares/diagnóstico por imagem , Pneumopatia Veno-Oclusiva/etiologia , Tempo , Fatores de Tempo , Resultado do Tratamento
6.
Kaohsiung J Med Sci ; 17(1): 36-45, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11411258

RESUMO

This study was conducted to investigate the maternal-fetal attachment, pregnancy stress and life-event stress of women during their third trimester and to explore the predictors of the maternal-fetal attachment. Purposive sampling was used to recruit 150 subjects from two hospitals in Kaohsiung. Four instruments were used to collect data: (a) the Demographic Data Questionnaire, (b) the Modified Maternal Fetal Attachment Scale, (c) The Pregnancy Stress Rating Scale, and (d) the Assessment Chart for Stressful Events of Adult Life. Factor analysis of the Modified Maternal Fetal Attachment scale defined four factors: (1) interacting with the fetus, (2) giving of self, (3) identifying the fetus, and (4) fantasizing. Results of the stepwise multiple regression indicated that the best subsets to predict the criterion variable of maternal-fetal attachment, including parity, attendance of prenatal class, stress from seeking safe passage for herself and her child through pregnancy, and the life-event stress, accounted for 32% of variance.


Assuntos
Comportamento Materno , Relações Mãe-Filho , Estresse Fisiológico/etiologia , Adulto , Feminino , Humanos , Gravidez , Terceiro Trimestre da Gravidez
7.
Zhonghua Yi Xue Za Zhi (Taipei) ; 64(12): 693-702, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11922488

RESUMO

BACKGROUND: Pulse wave velocity (PWV) is a surrogate marker of arteriosclerosis. It can be measured by recording pressure or flow wave signals at two recording sites of an arterial segment simultaneously or sequentially. However, it is unknown how the values of pulse wave velocity derived from various techniques can be compared. Thus, the aims of the present study were to investigate whether different techniques result in different values of PWV. METHODS: We measured aortic PWV from 101 uremic and non-uremic patients using both applanation tonometry and Doppler velocimetry by sequential method. To evaluate whether there is a difference between the sequentially and simultaneously derived PWV, simultaneous method using 2 tonometer or 2 Doppler probes was also applied in 50 and 23 subjects, respectively. RESULTS: There was no significant difference between PWV derived from sequential and simultaneous tonometry (933+/-310 cm/s and 919+/-301 cm/s,p = 0.09). Likewise, there was no significant difference between PWV derived from sequential and simultaneous velocimetry (778+/-241 cm/s and 761+/-205 cm/s,p = 0.35). However, PWV determined by sequential tonometry was significantly greater than (949+/-315 cm/s and 735+/-208 cm/s, respectively,p < 0.001), yet also significantly correlated with that determined by sequential velocimetry (r = 0.83, p < 0.001). CONCLUSIONS: Sequential applanation tonometry is a practical approach to measure PWV in view of technical convenience and the cost of equipment and manpower. Furthermore, we should be cautious in interpreting PWV derived from different methodologies as greater PWV value might be obtained by applanation tonometry than by Doppler velocimetry.


Assuntos
Pulso Arterial , Adulto , Idoso , Feminino , Humanos , Fluxometria por Laser-Doppler , Masculino , Pessoa de Meia-Idade
8.
Clin Cardiol ; 23(11): 825-30, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11097129

RESUMO

BACKGROUND: The incidence of syncope increases with age, while aging is also associated with increased arterial wave reflection. HYPOTHESIS: The study was undertaken to determine whether increased arterial wave reflection is a predisposing factor of syncope. METHODS: We recruited 38 patients (28 men and 10 women, mean age 57.2 +/- 20.3 years, range 17-87 years) with a history of syncope within 6 months of entry. The etiology of syncope was documented for each patient by a complete assessment of vasomotor function and cerebral flow. All patients received a comprehensive echocardiographic evaluation of cardiac structure and function. Carotid augmentation index (AI) was estimated noninvasively with the tonometry technique. The results were compared with those from 54 age- and gender-matched controls. RESULTS: The most frequent diagnoses of syncope were postural hypotension (13 patients) and cerebrovascular dysautoregulation (10 patients), and the cause could not be determined in 9 patients. Compared with the control group, the syncope group had a greater AI (20 +/- 21 vs. 10 +/- 15%, p = 0.013). Subgroup analysis of 20 patients aged > 50 years and with the aforementioned diagnoses showed even more striking results: AI, 29 +/- 10 vs. 11 +/- 15%, p < 0.001. The enhanced augmentation in the patients remained when age, systolic blood pressure, height, and heart rate were accounted for. Analysis of the carotid pulse wave suggested that both the timing and intensity of wave reflection were enhanced in patients with a history of syncope compared with controls. CONCLUSIONS: Our results support the hypothesis that enhanced arterial wave reflection is associated with the occurrence of syncope, especially in the elderly.


Assuntos
Envelhecimento/fisiologia , Artérias/fisiopatologia , Síncope/fisiopatologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Pressão Sanguínea , Artérias Carótidas/fisiopatologia , Interpretação Estatística de Dados , Ecocardiografia , Feminino , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Pulso Arterial , Síncope/etiologia , Teste da Mesa Inclinada , Ultrassonografia Doppler Transcraniana
9.
J Biol Chem ; 275(49): 38794-801, 2000 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-10993881

RESUMO

LIGHT is a member of the tumor necrosis factor superfamily and is the ligand for LT-betaR, HVEM, and decoy receptor 3. LIGHT has a cytotoxic effect, which is further enhanced by the presence of interferon-gamma (IFN-gamma). Although LIGHT/IFN-gamma can activate caspase activity, neither benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone nor benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone can completely inhibit LIGHT/IFN-gamma-mediated apoptosis. Moreover, overexpression of Bcl-2 further enhances LIGHT/IFN-gamma-mediated apoptosis. It appears that LIGHT and IFN-gamma act synergistically to activate caspase-3, with the resultant cleavage of Bcl-2, removal of the BH4 domain, leading to conversion of Bcl-2 from an antiapoptotic to a proapoptotic form in p53-deficient hepatocellular carcinoma Hep3BT2 cells. Thus, LIGHT seems to be able to override the protective effect of Bcl-2 and induce cell death. Although benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone and benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone can prevent the cleavage of Bcl-2 by LIGHT/IFN-gamma, they only partially inhibit apoptosis in Hep3BT2 cells that are overexpressing Bcl-2. In contrast, both LIGHT/IFN-gamma-mediated apoptosis and Bcl-2 cleavage are inhibited by free radical scavengers, indicating that free radicals may play an essential role in LIGHT/IFN-gamma-mediated apoptosis at a step upstream of caspase-3 activation. These results suggest that LIGHT signaling may diverge into multiple, separate processes.


Assuntos
Apoptose/fisiologia , Genes bcl-2 , Interferon gama/farmacologia , Proteínas de Membrana/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Sequência de Aminoácidos , Apoptose/efeitos dos fármacos , Neoplasias da Mama , Carcinoma Hepatocelular , Caspase 3 , Inibidores de Caspase , Caspases/metabolismo , Inibidores de Cisteína Proteinase/farmacologia , Feminino , Humanos , Cinética , Neoplasias Hepáticas , Proteínas de Membrana/fisiologia , Dados de Sequência Molecular , Proteínas Proto-Oncogênicas c-bcl-2/química , Proteínas Proto-Oncogênicas c-bcl-2/genética , Fator de Crescimento Transformador beta/farmacologia , Células Tumorais Cultivadas , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa/fisiologia
10.
Am J Chin Med ; 28(2): 279-89, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10999447

RESUMO

Pulse analysis is a powerful method in Chinese medicine. We suggest that the effect of herbal medicine is to redistribute the blood to organs and meridians. In this report, by injecting extracts into rats and then analyzing the blood pressure wave measured at the caudate arteries, we studied eight important spleen meridian related herbs: They were Semen Lablab, Fructus Amomi Globosi, Rhizoma Atractylodis Macrocephalae, Rhizoma Atractylodis, Tuber Pinelliae, Radix Codonopsitis, Pericarpium Aurantii and Rhizoma Polygonati. All eight herbs increased the intensity of the 3rd harmonic (C3) of the pressure pulse which is correlated to the spleen and spleen meridian, as described in traditional Chinese medical literature. All of them also increased the 2nd harmonic (which is correlated to the kidney and the kidney meridian) as well as decreased the heart load (DC term of pressure wave, C0). Tuber Pinelliae, Radix Codonopsitis, Pericarpium Aurantii and Rhizoma Polygonati decreased the 1st harmonic (correlated to the liver meridian) significantly, while Rhizoma Atractylodis Macrocephalae only decreased C1 slightly. Except for Semen Lablab, all the others decreased the intensity of the 5th (stomach meridian) and the 7th harmonics. The effects of kidney herbs: Cortex Eucommiae and Radix Achyranthis were also shown for comparison.


Assuntos
Artérias/efeitos dos fármacos , Medicamentos de Ervas Chinesas/farmacologia , Meridianos , Baço/irrigação sanguínea , Animais , Pressão Sanguínea/efeitos dos fármacos , Pulso Arterial , Ratos , Ratos Wistar
12.
Am J Chin Med ; 28(1): 41-55, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10794116

RESUMO

We investigated the pulse spectrum variation of the human radial artery when Hsien- Ku (St 43), an acupoint on the stomach meridian, was needled and compared the results with the acupuncture effects of two other acupoints, Tsu-San-Li (St-36) and Tai-Shih (K-3), reported previously. For Hsien-Ku, the harmonic proportions were redistributed: the second harmonic (C2) decreased, C3, C5, C6, C7, C8 and C9 increased, C3, C6 and C9 became the relative peaks to their neighboring harmonics and C2, C4 became the relative minimums. The phase angles of the 2nd harmonic (P2) and 5th harmonic (P5) decreased, propagating faster. These effects were similar to that of Tsu-San-Li which is also on the stomach meridian. A totally different pattern was found for Tai-Shih on the kidney meridian. These results strengthen the theory that a meridian can be classified according to its effects on the pulse spectrum, and that all the meridian related effects such as those caused by acupuncture or meridian specific herbs are frequency specific.


Assuntos
Terapia por Acupuntura , Medicina Tradicional Chinesa , Pulso Arterial , Artéria Radial/fisiologia , Terapia por Acupuntura/métodos , Terapia por Acupuntura/estatística & dados numéricos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estômago
13.
Pacing Clin Electrophysiol ; 22(11): 1614-9, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10598964

RESUMO

UNLABELLED: Early recurrence of atrial fibrillation (AF) has been reported to occur in a significant number of patients after internal cardioversion. However, information about early recurrence of AF after external cardioversion has never been reported. The present study was conducted to investigate the clinical and electrophysiological characteristics of early recurrence of AF and its role in failure of cardioversion in patients with chronic AF. METHODS AND RESULTS: The study included 50 consecutive patients, age 69+/-9, with a history of chronic AF for more than 3 months duration and electrical cardioversion. They were divided into two groups according to the presence (group 1) or absence (group 2) of early recurrence of AF. There were 13 (26%) patients in group 1 and 37 (74%) patients in group 2. The age, gender, duration of AF, left ventricular function, left atrial dimension, and underlying heart disease were similar between group 1 and 2. Forty-five patients were successfully converted to sinus rhythm with a mean energy of 158+/-57 . Among those who failed to be converted to sinus rhythm, 4 (80%) belonged to group 1 and 1 (20%) belonged to group 2. The early recurrences of AF were initiated with consecutive APDs; but the numbers of APD in the first 30 seconds after cardioversion were similar between group 1 and 2. However, the coupling interval of the second APD was shorter in group 1 than group 2 (188+/-22 vs 324+/-59 ms, P = 0.003). Nine of the 13 early recurrences were prevented by an increase of shock energy (n = 3) or intravenous amiodarone infusion (n = 6). There were no differences in duration of follow-up, recurrence rate, and time interval to recurrence between group 1 and group 2. Early recurrence of AF occurred in 26% of chronic AF patients who underwent external electrical cardioversion and was a major cause of failure in cardioversion. Early recurrence of AF was initiated by APDs with decreasing coupling intervals and could be prevented with an increase of shock energy or amiodarone.


Assuntos
Fibrilação Atrial/terapia , Cardioversão Elétrica , Idoso , Amiodarona/administração & dosagem , Antiarrítmicos/administração & dosagem , Fibrilação Atrial/etiologia , Doença Crônica , Eletrocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Retratamento , Falha de Tratamento
14.
J Inorg Biochem ; 76(3-4): 197-209, 1999 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-10605837

RESUMO

The syntheses, isolation and characterization of cyclohexylthiolatocobalamin (C6H11SCbl), glutathionylcobalamin (GluSCbl), and cysteinylcobalamin (CysSCbl) are reported in 75, 55, and 65% yield, respectively. Characterization was achieved using elemental analyses, L-SIMS (liquid secondary ion mass spectrometry), UV-visible spectroscopy and, for the more stable C6H11SCbl and GluSCbl, our recently established 1H NMR method (which emphasizes the readily interpreted aromatic region of the cobalamin's 1H NMR spectrum). Preliminary evidence is presented for clean homolysis of the RS-Co bond in C6H11SCbl, GluSCbl, and CysSCbl to give RS. and .Co(II)Cbl radical pairs analogous to those that are intermediates in ribonucleoside triphosphate reductase (RTPR). A summary is provided which emphasizes the seven variables identified to date, underlying the successful syntheses and isolation of thiolatocobalamins, variables which make the one-step syntheses of RSCbls considerably more complex than they initially appear. Also briefly discussed are the analogous protein-S-Cbl complexes that are seen as side-products in RTPR, and the probability that such side-products are formed when HOCbl.HX is used as a possible 'active-site inhibitor' complex with B12-dependent enzymes.


Assuntos
Cobamidas/metabolismo , Glutationa/análogos & derivados , Ribonucleotídeo Redutases/metabolismo , Vitamina B 12/análogos & derivados , Vitamina B 12/síntese química , Glutationa/síntese química , Ligantes , Metanol , Espectrofotometria , Água
15.
Circulation ; 100(18): 1879-86, 1999 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-10545432

RESUMO

BACKGROUND: Atrial fibrillation (AF) can be initiated by ectopic beats originating from the atrial or great venous tissues. This study investigated the anatomic characteristics and electrophysiological properties of pulmonary veins (PVs), as well as the possible mechanisms and response to drugs of ectopic foci, and assessed the effects of radiofrequency (RF) ablation on AF initiated by ectopic beats originating from PVs. METHODS AND RESULTS: Seventy-nine patients with frequent episodes of paroxysmal AF and 10 control patients were included. Distal PVs showed the shortest effective refractory periods (ERPs), and right superior PVs showed a higher incidence of intra-PV conduction block than left superior PVs. Superior and left PVs had longer myocardial sleeves than inferior and right PVs, respectively. These electrophysiological characteristics were similar between AF and control patients. Propranolol, verapamil, and procainamide suppressed ectopic beats that originated from the PVs. Of 116 ectopic foci that initiated AF, 103 (88.8%) originated from PVs. A mean of 7+/-3 RF applications completely eliminated 110 ectopic foci (94.8%). During the 6+/-2-month follow-up period, 68 patients (86. 1%) were free of AF without any antiarrhythmic drugs. Follow-up transesophageal echocardiogram showed 42.4% of ablated PVs had focal stenosis. One patient had mild exertional dyspnea after ablation, but it resolved 3 months later; 1 patient had onset of mild exertional dyspnea 5 months after ablation. CONCLUSIONS: Electrophysiological characteristics of PVs are different from those in the atria. Ectopic beats from PVs can initiate AF, and beta-adrenergic receptor blocker, calcium channel blockers, and sodium channel blockers can suppress these ectopic beats. Careful mapping and elimination of these ectopic foci can cure paroxysmal AF.


Assuntos
Antiarrítmicos/uso terapêutico , Fibrilação Atrial/terapia , Complexos Atriais Prematuros/terapia , Ablação por Cateter , Veias Pulmonares/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Fibrilação Atrial/etiologia , Fibrilação Atrial/fisiopatologia , Complexos Atriais Prematuros/complicações , Complexos Atriais Prematuros/fisiopatologia , Eletrocardiografia/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procainamida/uso terapêutico , Propranolol/uso terapêutico , Resultado do Tratamento , Verapamil/uso terapêutico
16.
Cardiology ; 92(3): 145-50, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10754343

RESUMO

Previous reports did not encourage balloon mitral commissurotomy (BMC) when left atrial (LA) thrombi were located beyond LA appendage. We hypothesize that LA thrombi may be resolved in some patients after anticoagulant therapy, and BMC can be performed subsequently. In the present study, we used transesophageal echocardiography (TEE) to evaluate the effects of anticoagulant on LA thrombi in patients with mitral stenosis, to compare the clinical differences between patients with (group A) and without (group B) resolution of LA thrombi, and to evaluate the safety of subsequent BMC in these patients. TEE was performed on 190 consecutive patients with mitral stenosis; 14 (7.4%) of them were found with LA thrombi. Serial TEE was performed and optimal anticoagulant therapy was achieved in all 14 patients. The thrombi were located within the LA appendage in 6 cases, attached to the LA posterior wall in 5, posterior wall and interatrial septum in 1, and LA appendage and posterior wall in 2. Based on the 6-month TEE follow-up, we found that the LA thrombi disappeared in 8 (57.2%) patients (group A) and persisted in 6 patients (group B). LA thrombi resolved within 3 months in 7 group A patients (87.5%). Furthermore, the resolution of LA thrombi was more frequently observed in patients either with a smaller LA dimension (51.9 +/- 3.4 vs. 57.8 +/- 4.8 mm, p = 0.02) or with their thrombi located inside their LA appendage (p = 0.03). No differences in other clinical and echocardiographic variables were noted between these two groups. Subsequently, group A patients underwent BMC without complications of systemic embolization. In conclusion, LA thrombi can be resolved after optimal anticoagulant therapy in a considerable proportion of patients with mitral stenosis. Serial TEE studies are helpful to observe LA thrombus resolution; they may also be useful in planning the treatment strategy.


Assuntos
Cateterismo , Ecocardiografia Transesofagiana , Átrios do Coração , Cardiopatias/complicações , Estenose da Valva Mitral/terapia , Trombose/complicações , Adulto , Idoso , Anticoagulantes/uso terapêutico , Feminino , Cardiopatias/diagnóstico por imagem , Cardiopatias/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade , Estenose da Valva Mitral/complicações , Estenose da Valva Mitral/diagnóstico por imagem , Terapia Trombolítica , Trombose/diagnóstico por imagem , Trombose/tratamento farmacológico , Resultado do Tratamento
17.
J Clin Invest ; 102(6): 1142-51, 1998 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-9739048

RESUMO

LIGHT is a new member of tumor necrosis factor (TNF) cytokine family derived from an activated T cell cDNA library. LIGHT mRNA is highly expressed in splenocytes, activated PBL, CD8(+) tumor infiltrating lymphocytes, granulocytes, and monocytes but not in the thymus and the tumor cells examined. Introduction of LIGHT cDNA into MDA-MB-231 human breast carcinoma caused complete tumor suppression in vivo. Histological examination showed marked neutrophil infiltration and necrosis in LIGHT expressing but not in the parental or the Neo-transfected MDA-MB-231 tumors. Interferon gamma (IFNgamma) dramatically enhances LIGHT-mediated apoptosis. LIGHT protein triggers apoptosis of various tumor cells expressing both lymphotoxin beta receptor (LTbetaR) and TR2/HVEM receptors, and its cytotoxicity can be blocked specifically by addition of a LTbetaR-Fc or a TR2/HVEM-Fc fusion protein. However, LIGHT was not cytolytic to the tumor cells that express only the LTbetaR or the TR2/HVEM or hematopoietic cells examined that express only the TR2/HVEM, such as PBL, Jurkat cells, or CD8(+) TIL cells. In contrast, treatment of the activated PBL with LIGHT resulted in release of IFNgamma. Our data suggest that LIGHT triggers distinct biological responses based on the expression patterns of its receptors on the target cells. Thus, LIGHT may play a role in the immune modulation and have a potential value in cancer therapy.


Assuntos
Apoptose , Genes Supressores de Tumor , Proteínas de Membrana/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Receptores Virais/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Mapeamento Cromossômico , Meios de Cultura Livres de Soro , Feminino , Técnicas de Transferência de Genes , Humanos , Hibridização in Situ Fluorescente , Interferon gama/metabolismo , Ligantes , Ativação Linfocitária , Linfócitos do Interstício Tumoral , Receptor beta de Linfotoxina , Masculino , Proteínas de Membrana/genética , Membro 14 de Receptores do Fator de Necrose Tumoral , Células Tumorais Cultivadas , Membro 14 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa/genética
18.
Circulation ; 98(5): 422-8, 1998 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-9714092

RESUMO

BACKGROUND: Many cardiovascular and noncardiovascular parameters are thought to be determinants of left ventricular mass (LVM). Complicated interactions necessitate the simultaneous measurement and consideration of each to determine their individual and collective impact on LVM. We undertook such a comprehensive study. METHODS AND RESULTS: The influence of anthropometry, cardiac size and contractility, arterial structure and function, as well as indices of lifestyle, physical activity, and dietary salt intake on LVM (by two-dimensionally guided M-mode echocardiography) was analyzed in 1315 Chinese subjects who were either normotensive or had untreated hypertension. Effects of many cardiac and arterial factors were assessed. In univariate analysis, almost all measured noncardiovascular, cardiac, and arterial variables were significantly correlated with LVM. In multivariate linear regression analyses, when age, sex, body habitus, fasting serum C-peptide level, dietary salt, physical activity, and lifestyle were accounted for, the optimum multivariate linear regression main effects model had an adjusted model r2 of 0.740, with 98% of the model variance accounted for by the 5 independent determinants of LVM: stroke volume (49.6%), systolic blood pressure (30.7%), contractility (14.7%), body mass index (1.8%), and aortic root diameter (1.6%). Other proposed arterial indices were significant independent determinants of LVM only when blood pressure was removed from the model and, even then, these indices not only resulted in less powerful prediction but also accounted for only a very small percentage of the total variance of LVM. CONCLUSIONS: In a large population, we (1) confirmed that age, body habitus, and some indexes of arterial structure and function are independent determinants of LVM; (2) found aortic diameter to be an independent structural determinant of LVM; (3) demonstrated that the effects of the derived measures of arterial function were small and provided no better predictive power than blood pressure alone; and (4) showed that when the best measures of cardiac and vascular load were included, the single most potent predictor was an index of left ventricular size.


Assuntos
Sistema Cardiovascular/fisiopatologia , Hipertrofia Ventricular Esquerda/diagnóstico , Adulto , Idoso , Antropometria , Ecocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Hemodinâmica , Humanos , Hipertrofia Ventricular Esquerda/fisiopatologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Análise de Regressão , Fatores de Risco , Taiwan
19.
Am J Chin Med ; 26(1): 73-82, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9592596

RESUMO

Pulse analysis method was used in studying the traditional Chinese formula Liu-Wei-Dihuang as well as five of its main components (Rehmannia glutinosa, Cornus officinalis, Paeonia Suffruticosa, Poria cocos and Alisma plantogo-aquatica var oriental). Based on our recently developed resonance theory, we tried to elucidate the mechanism and mutual reactions of these meridian related herbs. Hot water herbal extracts were injected intraperitoneally into rats and the pressure pulse spectrum at the caudate artery was measured. The results of this study indicated that Liu-Wei-Dihuang mildly increased blood flow to meridians with lower resonance frequency: namely the liver C1, the kidney C2 and the spleen C3; but decreased blood flow to the higher resonance frequency organs and meridians: the lung C4, the stomach C5, the gall bladder C6, and the bladder C7. It also decreased the heart load C0. All of the five herb components increased blood flow to the kidney C2 and the spleen C3; but their effects on the high frequency organs varied. Alisma plantogo-aquatica var. oriental decreased the C0, C5, C6, C7; Poria cocos decreased C1, C4, C5, C6; Rehmannia glutinosa, Paeonia Suffruticosa decreased C0, C4, C5, C6, C7; Cornus officinalis increased C4 but decreased C0, C5, C6, C7.


Assuntos
Pressão Sanguínea/efeitos dos fármacos , Medicamentos de Ervas Chinesas/administração & dosagem , Meridianos , Animais , Combinação de Medicamentos , Pulso Arterial , Ratos , Ratos Sprague-Dawley
20.
J Vet Med Sci ; 60(2): 253-5, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9524953

RESUMO

An survey of Theileria parasite infection in cattle in Taiwan was carried out by polymerase chain reaction (PCR). A total of 491 blood samples, 105 from southern area and 386 from northern area, were collected from bovine in 16 different farms. From northern area, Theileria piroplasms could be seen in only 4 of 105 blood samples microscopically. However, when p32/34 genes (encoding immunodominant piroplasm surface proteins) were amplified by PCR, 15 blood samples were detected positive. They were analyzed by using allele-specific primers of 3 allelic forms of p32/34 and all contained C type of T. sergenti. Four blood samples were found infected with both C and B (T. buffeli) type parasites. Examination of 386 blood samples from southern area of Taiwan did not reveal any Theileria parasite microscopically, as well as by PCR amplification.


Assuntos
Theileria/classificação , Theileriose/diagnóstico , Animais , Bovinos , Demografia , Reação em Cadeia da Polimerase/métodos , Taiwan/epidemiologia , Theileria/genética , Theileria/isolamento & purificação , Theileriose/epidemiologia
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