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1.
Phys Rev Lett ; 128(9): 091302, 2022 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-35302802

RESUMO

We search for the signature of parity-violating physics in the cosmic microwave background, called cosmic birefringence, using the Planck data release 4. We initially find a birefringence angle of ß=0.30°±0.11° (68% C.L.) for nearly full-sky data. The values of ß decrease as we enlarge the Galactic mask, which can be interpreted as the effect of polarized foreground emission. Two independent ways to model this effect are used to mitigate the systematic impact on ß for different sky fractions. We choose not to assign cosmological significance to the measured value of ß until we improve our knowledge of the foreground polarization.

2.
J Vet Cardiol ; 38: 44-58, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34800922

RESUMO

INTRODUCTION: Although degenerative mitral valve disease (DMVD) is essentially a disorder of the valve, the progression of the disease leads to structural myocardial changes that may compromise left ventricular systolic function. Tissue motion annular displacement (TMAD) is a surrogate for longitudinal fiber function based on speckle tracking assessment of the movement of the mitral annulus toward the apex during systole. The aim of this study was to evaluate longitudinal systolic function with TMAD in dogs with DMVD. ANIMALS: Ninety-four dogs with DMVD and 32 healthy dogs. METHODS: Prospective cross-sectional observational study. Dogs with DMVD of various American College of Veterinary Internal Medicine classification stages and healthy control dogs underwent physical examination, electrocardiography, systolic blood pressure measurement, as well as a standard and speckle tracking echocardiography. Global longitudinal strain (GLS) and TMAD were used to assess longitudinal systolic function. RESULTS: The global TMADmm and global TMAD% were higher in American College of Veterinary Internal Medicine B2 animals than in the stage CD. Global TMAD (mm/kg,mm/bodyweight3, mm/m2) were correlated with GLS and ejection fraction. Global TMAD (mm/kg,mm/m2,%) and GLS were influenced by sex. In addition, systolic blood pressure influenced GLS (P < 0.01; r = -0.23), global TMADmm/kg (P = 0.017; r = -0.21) and global TMADmm/m2 (P = 0.031; r = -0.19). Tissue motion annular displacement was fast to be performed and produced good repeatability in dogs with DMVD. CONCLUSIONS: Global TMAD (mm,%), was reduced in DMVD dogs with clinical signs of heart failure compared with stage B2. Tissue motion annular displacement was shown to be a repeatable technique for evaluation of longitudinal systolic function in dogs with DMVD.


Assuntos
Valva Mitral , Função Ventricular Esquerda , Animais , Estudos Transversais , Cães , Valva Mitral/diagnóstico por imagem , Estudos Prospectivos , Sístole
3.
Radiographics ; 21(6): 1475-90, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11706218

RESUMO

The root of the small-bowel mesentery (SBM) is an important peritoneal fold that is contiguous to other peritoneal ligaments and mesocolons. Several pathologic conditions can occur in the SBM itself, and diseases that spread through the connections from adjacent organs frequently involve it. The root of the SBM is contiguous to the hepatoduodenal ligament around the superior mesenteric vein (SMV) and contiguous to the right side of the transverse mesocolon around the gastrocolic trunk. The inferior mesenteric vein, which is a landmark of the descending mesocolon, runs along the left side of the root of the SBM. Malignant neoplasms can spread to the SBM by means of direct extension, extension along the neural plexus, extension along neighboring ligaments, or extension along lymphatic vessels. Inflammatory conditions such as pancreatitis and perforation of a jejunal diverticulum can also spread to the SBM. Anomalies that can occur in the SBM include rotation anomalies and internal hernia. Vascular lesions of the SBM include thrombosis of the superior mesenteric artery (SMA), acute SMV thrombosis, SMA dissection, arterioportal fistula, and portal venous gas. Other pathologic conditions that can occur in the SBM are edema or congestion, mesenteric tear, mesenteric panniculitis, and tumors or tumorlike lesions.


Assuntos
Mesentério/anatomia & histologia , Mesentério/diagnóstico por imagem , Doenças Peritoneais/diagnóstico por imagem , Doenças Peritoneais/patologia , Neoplasias Peritoneais/diagnóstico por imagem , Neoplasias Peritoneais/patologia , Tomografia Computadorizada por Raios X , Humanos , Intestino Delgado
4.
Astrophys J ; 533(2): L83-L87, 2000 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-10770696

RESUMO

We investigate the weak gravitational lensing effect that is due to the large-scale structure of the universe on two-point correlations of local maxima (hot spots) in the two-dimensional sky map of the cosmic microwave background (CMB) anisotropy. According to the Gaussian random statistics, as most inflationary scenarios predict, the hot spots are discretely distributed, with some characteristic angular separations on the last scattering surface that are due to oscillations of the CMB angular power spectrum. The weak lensing then causes pairs of hot spots, which are separated with the characteristic scale, to be observed with various separations. We found that the lensing fairly smooths out the oscillatory features of the two-point correlation function of hot spots. This indicates that the hot spot correlations can be a new statistical tool for measuring the shape and normalization of the power spectrum of matter fluctuations from the lensing signatures.

5.
Astrophys J ; 526(1): L1-L4, 1999 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-10534447

RESUMO

We present angular power spectra of the cosmic microwave background radiation anisotropy due to fluctuations of the Sunyaev-Zeldovich (SZ) effect through clusters of galaxies. A contribution from the correlation among clusters, which has been neglected in previous analyses, is especially focused on. Employing the evolving linear bias factor based on the Press-Schechter formalism, we find that the clustering contribution amounts to 20%-30% of the Poissonian contribution at degree angular scales. If we exclude clusters in the local universe, it even exceeds the Poissonian noise and makes the dominant contribution to the angular power spectrum. As a concrete example, we demonstrate the subtraction of the ROSAT X-ray and Planck SZ flux-limited cluster samples. It indicates that we should include the clustering effect in the analysis of the SZ fluctuations. We further find that the degree scale spectra essentially depend upon the normalization of the density fluctuations, i.e., sigma8, and the gas mass fraction of the cluster, rather than the density parameter of the universe and details of cluster evolution models. Our results show that the SZ fluctuations at the degree scale will provide a possible measure of sigma8, while the arcminute spectra will provide a probe of the cluster evolution. In addition, the clustering spectrum will give us valuable information on the bias at high redshift, if we can detect it by removing X-ray or SZ luminous clusters.

6.
J Obstet Gynaecol Res ; 24(1): 33-6, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9564103

RESUMO

We present a case of fetal autosomal recessive polycystic kidney disease (ARPKD) at 34 weeks of gestation, diagnosed by magnetic resonance imaging (MRI). MRI demonstrated enlarged fetal kidneys that were low signal intensity on T1-weighted images and high signal intensity on T2-weighted images. These MRI findings suggested a high water content in the renal parenchyma, consistent with the innumerable, tiny renal cysts present in ARPKD.


Assuntos
Doenças Fetais/diagnóstico , Rim/embriologia , Rim Policístico Autossômico Recessivo/diagnóstico , Adulto , Evolução Fatal , Feminino , Doenças Fetais/embriologia , Doenças Fetais/patologia , Humanos , Rim/diagnóstico por imagem , Rim/patologia , Imageamento por Ressonância Magnética , Masculino , Rim Policístico Autossômico Recessivo/embriologia , Rim Policístico Autossômico Recessivo/patologia , Gravidez , Terceiro Trimestre da Gravidez , Ultrassonografia Pré-Natal
7.
Neuroradiology ; 39(5): 326-8, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9189876

RESUMO

We report MRI in a patient with portal-systemic encephalopathy, in which the high signal in the basal ganglia on T1-weighted images showed marked resolution after successful embolization of the intrahepatic portal-systemic venous shunt.


Assuntos
Gânglios da Base/patologia , Embolização Terapêutica , Encefalopatia Hepática/diagnóstico , Imageamento por Ressonância Magnética , Veia Porta , Idoso , Feminino , Encefalopatia Hepática/etiologia , Veias Hepáticas/anormalidades , Humanos , Veia Porta/anormalidades
8.
Br J Pharmacol ; 120(6): 1172-8, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9134232

RESUMO

1. The aim of this study was to determine whether BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, could suppress an atherogenic process such as intimal thickening by a mechanism other than lowering the level of serum cholesterol. 2. First, we evaluated the in vitro effect of BAYw on the proliferation of vascular smooth muscle cells (SMC) from various species: Sprague-Dawley (SD) rats. New Zealand (NZ) white rabbits, intimal cells from Watanabe hereditary hyperlipidemic (WHHL) rabbit and SMC from the new-born human aorta. The increasing rate of total protein content of these cells was inhibited by the addition of BAYw in a dose-dependent fashion. In the presence of 2% foetal calf serum (FCS), the value of IC50 was 1.0 microM in SD rats, 2.1 microM in NZ white rabbits, and 0.3 microM in WHHL rabbits. With human SMC, the value was 0.02 microM in the presence of 10% FCS and 0.2 microM with a mixture of growth factors. 3. Based on these above in vitro findings, we next examined the in vivo effect of the agent to determine whether it could suppress rabbit intimal thickening induced by balloon catheterization. A balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta to denude the endothelium of the left common carotid artery in Japanese white rabbits. After 12 days they were divided into control and BAYw groups. The former were subcutaneously injected with saline and the latter with BAYw 1 mg kg-1 day-1. Two days after the beginning of treatment, a second balloon injury was performed to the previously injured left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and variously stained. Although the total serum cholesterol in the BAYw group was significantly lower than in the control (P < 0.05), the difference was not enough to affect intimal thickening. In addition, the BAYw group had a smaller intima/media ratio than the control group, decreasing to 45% of control (P < 0.05). By anti-alpha smooth muscle actin antibody staining, these intimal thickening areas were entirely occupied by SMCs, and their amount was attenuated by BAYw. By anti-rabbit macrophage antibody (RAM 11) staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared to control (P < 0.01). 4. These results indicate that BAYw has an inhibitory effect on intimal thickening by attenuating intimal SMC proliferation and infiltration of macrophages, suggesting that BAYw could be effective in the prevention of the progression of atherosclerotic plaque-like restenosis after angioplasty.


Assuntos
Arteriosclerose/tratamento farmacológico , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases , Músculo Liso Vascular/efeitos dos fármacos , Piridinas/farmacologia , Animais , Arteriosclerose/metabolismo , Arteriosclerose/patologia , Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/metabolismo , Artérias Carótidas/patologia , Cateterismo , Divisão Celular/efeitos dos fármacos , Células Cultivadas , DNA/metabolismo , Humanos , Hiperlipidemias/tratamento farmacológico , Piridinas/administração & dosagem , Coelhos , Ratos , Ratos Sprague-Dawley , Estereoisomerismo
9.
Atherosclerosis ; 128(2): 251-4, 1997 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-9050782

RESUMO

To determine the in vivo activity of BAYw6228 (BAYw), a newly developed 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) reductase inhibitor, we examined its effect on balloon catheterization-induced carotid arterial intimal thickening in Japanese white rabbits. In all rabbits weighing approximately 3.5 kg, a balloon catheter was inserted from a peripheral branch of the left external carotid artery to the aorta in order to denude the endothelium of the left common carotid artery. At day 12, they were divided into control and BAYw groups. The latter were subcutaneously injected with BAYw, 1 mg/kg/day, for the following 17 days. At day 15, the second balloon catheterization was performed in the same left common carotid artery in both groups. After another two weeks, the left common carotid artery was removed and stained with Elastica-Masson (EM) and anti-rabbit macrophage antibody (RAM 11). With RAM 11 staining, the number of positive cells in the intimal thickening was markedly decreased in the BAYw group compared with the control group (P < 0.01). Compared with the area ratio of the thickened intima/media layer of the control group, that of the BAYw group was significantly decreased to 45% (P < 0.05). These results indicate that BAYw prevents accumulation of macrophages and consequently contributes to the inhibition of intimal thickening induced by balloon catheterization.


Assuntos
Artérias Carótidas/efeitos dos fármacos , Artérias Carótidas/patologia , Cateterismo , Inibidores Enzimáticos/farmacologia , Macrófagos/efeitos dos fármacos , Piridinas/farmacologia , Animais , Movimento Celular/efeitos dos fármacos , Inibidores de Hidroximetilglutaril-CoA Redutases , Imuno-Histoquímica , Macrófagos/fisiologia , Masculino , Neovascularização Fisiológica , Coelhos , Túnica Íntima/crescimento & desenvolvimento , Túnica Íntima/patologia
10.
Rev. cir. infant ; 6(4): 188-92, dic. 1996. ilus
Artigo em Espanhol | LILACS | ID: lil-218542

RESUMO

Alrededor del 20 por ciento de los pacientes con anomalias del descenso testicular, presentan uno o ambos testiculos no palpables. Se han utilizado diversos ex menes para localizar la gonada, con resultados poco satisfactorios. La laparoscopia es un metodo seguro y eficaz para la localizacion de los testiculos no palpables, permitiendo ademas la realizacion de procedimientos terapeuticos, como la ligadura de los vasos gonadales. La orquiectomia y la orquidopexia. Entre Mayo de 1987 y Abril de 1996, 28 niños con testiculo no palpable (4 de ellos bilaterales) y con edades entre 2 y 15 años, fueron sometidos a laparoscopia. De los 32 testiculos, 18 (56,2 por ciento) fueron localizados en el abdomen. En 8 casos se ligaron por esta via los vasos espermaticos, como primer tiempo de la tecnica de Fowler-Stephens, otros 10 testiculos fueron tratados con orquidopexia convencional. En 3 casos (9,4 por ciento) se diagnostic" agenesia testicular, 6 eran "vanished testis" (18,8 por ciento) y 5 (15,6 por ciento) (2 "vanished y 3 que fueron descendidos). La ecografia no fu confiable, presentando resultados positivos en menos del 20 por ciento. El examen laparocopico permitio diagnosticar la presencia de la gonada y realizar procedimientos terapeuticos. Ademas ayudo a planificar el tratamiento convencional, con poco indice de complicaciones, por lo que es un procedimiento de eleccion en la pesquisa de los testiculos no palpables


Assuntos
Cirurgia Geral , Laparoscopia , Pediatria , Testículo
11.
Rev. cir. infant ; 6(4): 188-92, dic. 1996. ilus
Artigo em Espanhol | BINACIS | ID: bin-17873

RESUMO

Alrededor del 20 por ciento de los pacientes con anomalias del descenso testicular, presentan uno o ambos testiculos no palpables. Se han utilizado diversos ex menes para localizar la gonada, con resultados poco satisfactorios. La laparoscopia es un metodo seguro y eficaz para la localizacion de los testiculos no palpables, permitiendo ademas la realizacion de procedimientos terapeuticos, como la ligadura de los vasos gonadales. La orquiectomia y la orquidopexia. Entre Mayo de 1987 y Abril de 1996, 28 niños con testiculo no palpable (4 de ellos bilaterales) y con edades entre 2 y 15 años, fueron sometidos a laparoscopia. De los 32 testiculos, 18 (56,2 por ciento) fueron localizados en el abdomen. En 8 casos se ligaron por esta via los vasos espermaticos, como primer tiempo de la tecnica de Fowler-Stephens, otros 10 testiculos fueron tratados con orquidopexia convencional. En 3 casos (9,4 por ciento) se diagnostic" agenesia testicular, 6 eran "vanished testis" (18,8 por ciento) y 5 (15,6 por ciento) (2 "vanished y 3 que fueron descendidos). La ecografia no fu confiable, presentando resultados positivos en menos del 20 por ciento. El examen laparocopico permitio diagnosticar la presencia de la gonada y realizar procedimientos terapeuticos. Ademas ayudo a planificar el tratamiento convencional, con poco indice de complicaciones, por lo que es un procedimiento de eleccion en la pesquisa de los testiculos no palpables


Assuntos
Cirurgia Geral , Pediatria , Laparoscopia , Testículo
12.
J Thorac Imaging ; 11(2): 158-60, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-8820027

RESUMO

Infectious mononucleosis occurs most commonly among adolescents and young adults. Moreover, intrathoracic involvement by infectious mononucleosis, especially pulmonary consolidation, is uncommon. Thoracic computed tomography (CT) showed a massive pulmonary consolidation in the right lower lobe, multiple mediastinal lymphadenopathy, and pleural effusion in a 41-year-old man with infectious mononucleosis. Histopathology confirmed that lymphocytes and plasma cells had infiltrated the peribronchial areas and alveolar septa, and showed alveolar exudates composed of amorphous fibrinous debris, lymphocytes, and macrophages.


Assuntos
Mononucleose Infecciosa/diagnóstico por imagem , Pneumopatias/diagnóstico por imagem , Adulto , Biópsia , Humanos , Mononucleose Infecciosa/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia , Pneumopatias/patologia , Linfonodos/patologia , Masculino , Tomografia Computadorizada por Raios X
14.
Nihon Igaku Hoshasen Gakkai Zasshi ; 55(11): 745-50, 1995 Sep.
Artigo em Japonês | MEDLINE | ID: mdl-8532506

RESUMO

To evaluate the usefulness of magnetic resonance imaging (MRI) in diagnosing residual or recurrent tumors of cervical cancer after radiation therapy, we investigated the time difference between MRI and gynecologic findings in the diagnosis of residual or recurrent tumor in 12 patients with invasive cervical cancer. We defined a positive finding for residual or recurrent tumor as an uterine cervical mass isointense to muscle on T1-weighted images and hyperintense on T2-weighted images, and when a positive biopsy specimen was obtained. Two patients were diagnosed as having a residual or recurrent tumor by MRI. Positivity was demonstrated four and seven months later, respectively. MRI was more useful in the earlier diagnosis of residual or recurrent tumor of cervical cancer after radiation therapy than uterine biopsy. There was one patient whose differentiation from residual tumor or radiation-induced necrosis or inflammation on MRI was difficult. MRI and gynecologic check-up at a regular interval after radiation therapy was needed to distinguish them. One patient was diagnosed as having a recurrent tumor by gynecologic finding three month earlier than by MRI. Follow-up MRI examinations at a regular interval in addition to gynecologic examination is necessary for the early detection of recurrent cervical cancer after radiation therapy.


Assuntos
Recidiva Local de Neoplasia/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Fatores de Tempo
15.
Nihon Shokakibyo Gakkai Zasshi ; 91(8): 1320-7, 1994 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-8089916

RESUMO

In 10 adult patients with hepatic portal venous gas (HPVG), the clinical significance of HPVG and the efficacy of X-ray computed tomography (CT) were evaluated. HPVG was associated with ischemic bowel disease (n = 3), trauma (n = 4), liver abscess (n = 1), sepsis (n = 1), and unknown etiology (n = 1). The diagnostic ability of CT for the detection of HPVG was far superior to that of plain abdominal radiograph. Of 9 patients who underwent CT, HPVG located in the left hepatic lobe in all patients, and also in right hepatic lobe in 7 patients. Gas could be recognized in the left lobe and the anterior segment of the right lobe more clearly than in the posterior segment of the right lobe because of its larger amount of intravenous collection. The mortality rate of our cases was 100%. Gas was demonstrated simultaneously in the portal vein radicles and hepatic veins on CT in 4 patients with no clinical evidence of sepsis, which suggested the possibility of intraparenchymal shift of gas from the portal vein into the hepatic vein. In a single case with sepsis, gas was noted in various vessels, including arteries, in addition to the portal venous system. The authors conclude that HPVG is still a grave sign in Japan and prompt appropriate treatment is required. CT may be of great value in the early detection of HPVG and may indicate its etiology.


Assuntos
Gases , Veia Porta/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Traumatismos Abdominais/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Oclusão Vascular Mesentérica/diagnóstico por imagem , Pessoa de Meia-Idade , Sepse/diagnóstico por imagem
16.
J Comput Assist Tomogr ; 18(2): 206-8, 1994.
Artigo em Inglês | MEDLINE | ID: mdl-8126268

RESUMO

OBJECTIVE: Thymic diseases can arise from remnants of thymic tissues along the path of fetal descent and may simulate thyroid tumors or lymphadenopathy. MATERIALS AND METHODS: We present two patients with a cervical mass arising from the cervical thymus that was caused by incomplete descent of the thymus into the mediastinum. RESULTS: In one patient a cervical mass was surgically confirmed to be a cervical thymoma, which simulated a thyroid cancer on CT and 201Tl-scintigraphy. In another patient, cervical thymic hyperplasia arising from an incompletely descended thymus was surgically confirmed. The isointensity between the cervical mass and an enlarged mediastinal thymus was recognized on MRI. CONCLUSION: If a cervical mass is located in the region of the lower pole of the thyroid or if there is a connection or the same intensity between the cervical mass and the mediastinal thymus on MRI, a diagnosis of a cervical mass of thymic origin should be considered.


Assuntos
Imageamento por Ressonância Magnética , Timoma/diagnóstico , Hiperplasia do Timo/diagnóstico , Neoplasias do Timo/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Doença de Graves/complicações , Humanos , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pescoço , Timoma/patologia , Hiperplasia do Timo/complicações , Hiperplasia do Timo/patologia , Neoplasias do Timo/patologia , Neoplasias da Glândula Tireoide/diagnóstico
17.
Circ Res ; 73(5): 935-42, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8403263

RESUMO

To clarify the changes in creatine kinase M localization along with the progress of myocardial ischemia, immunoelectron microscopic studies were performed using rabbit anti-canine creatine kinase M Fab'-horseradish peroxidase conjugate in 21 dogs. Myocardial ischemia was induced by occlusion of the left anterior descending coronary artery for 15 (n = 5), 30 (n = 5), 60 (n = 5), or 180 (n = 4) minutes. Two dogs were used as normal controls. As we have already demonstrated, most creatine kinase M in normal myocardial cells was localized over the entire A band in association with the thick filament, suggesting that creatine kinase in this region (A-band creatine kinase) was the enzyme coupled with myosin ATPase. After 15 minutes of ischemia, creatine kinase M showed only minimal changes in its location, indicating that A-band creatine kinase still has the ability to couple with myosin ATPase (reversible injury). However, after 30 minutes of ischemia, A-band creatine kinase diffused markedly to the I band (transitional phase), and after 60 minutes of ischemia, it leaked out to extracellular spaces (irreversible injury). After 180 minutes of ischemia, most A-band creatine kinase disappeared from the myocardial cells (coagulation necrosis). These features of creatine kinase M localization seemed to reflect each stage of ischemic cell injury. We conclude that myocardial ischemia results in a dissociation of creatine kinase molecules from the thick filament, which leads the energy transport system to destruction.


Assuntos
Creatina Quinase/análise , Isquemia Miocárdica/enzimologia , Miocárdio/enzimologia , Doença Aguda , Animais , Cães , Isoenzimas , Microscopia Imunoeletrônica , Isquemia Miocárdica/patologia , Miocárdio/ultraestrutura , Miosinas/análise
18.
Jpn Circ J ; 57(10): 969-78, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8230678

RESUMO

Myocardial ischemia interrupts neurotransmission and causes the depression of norepinephrine release. However, the effects of sympathetic nerve stimulation on neurotransmission and norepinephrine release in post-ischemic myocardium are not well defined. We measured regional myocardial length and norepinephrine (NE) release during sympathetic nerve stimulation in anesthetized dogs. Dogs were divided into 2 groups: Group 1 (n = 14); sympathetic nerve stimulation, Group 2 (n = 9); pre-treatment with alpha-blockade yohimbine hydrochloride (0.2 mg/kg) followed by sympathetic nerve stimulation. The left anterior descending artery was occluded for 15 min. Sympathetic nerve stimulation was performed before coronary occlusion and after reperfusion. In group 1, the decrease in systolic shortening in the ischemic region persisted for more than 60 min. Although sympathetic nerve stimulation caused an increase in systolic shortening, it was lower than the pre-ischemic value. NE release from the post-ischemic myocardium remained decreased for 60 min. The decrease in the post-ischemic myocardial response to sympathetic nerve stimulation was associated with diminished NE release. When the cardiac sympathetic nerve was denervated with an epicardial phenol application, NE release decreased even further. In group 2, NE release did not decrease following reperfusion. These results suggest that sympathetic nerve conduction is not completely impaired in post-ischemic myocardium and that pre-synaptic alpha -2 receptors might play an important role in diminished NE release.


Assuntos
Coração/fisiopatologia , Isquemia Miocárdica/fisiopatologia , Norepinefrina/metabolismo , Sistema Nervoso Simpático/fisiopatologia , Animais , Cães , Hemodinâmica/fisiologia , Reperfusão Miocárdica , Condução Nervosa/fisiologia , Ioimbina/farmacologia
19.
Cardiovasc Intervent Radiol ; 16(4): 245-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8402789

RESUMO

A 57-year-old woman presented with hepatic encephalopathy, cirrhosis, and a dual-channel portosystemic venous shunt (PSVS). The shunt was treated successfully by embolization with steel coils via retrograde systemic venous access. Encephalopathy resolved. This new approach is considered safer than the previously reported percutaneous transhepatic route or the mesenteric venous route, requiring a mini-laparotomy.


Assuntos
Embolização Terapêutica/métodos , Encefalopatia Hepática/terapia , Veias Hepáticas/anormalidades , Sistema Porta/anormalidades , Veia Porta/anormalidades , Cateterismo/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Veia Cava Inferior
20.
Jpn Circ J ; 55(9): 900-3, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1942495

RESUMO

To clarify the relationship between post-ischemic myocardial dysfunction and local cardiac sympathetic nerve function, we measured regional myocardial length and norepinephrine (NE) release during sympathetic nerve stimulation in 32 mongrel dogs. Coronary occlusion was produced by balloon occluder for 15 min and reperfused for 60 min. Dogs were divided into 3 groups as follows; Group 1 (n = 14): Sympathetic nerve stimulation, Group 2 (n = 9): Pre-treatment with yohimbine hydrochloride (0.2 mg/kg) and sympathetic nerve stimulation, Group 3 (n = 9): Exogenous NE administration. Sympathetic nerve stimulation or NE infusion were performed before occlusion and after reperfusion. In group 1, the extent of the increase in systolic shortening during sympathetic nerve stimulation (delta - shortening) lowered at 5 min after reperfusion and augmented progressively. But, delta-shortening at an early reperfusion period did not reduce in group 2 and 3. NE release from the ischemic myocardium decreased in group 1 and did not recover for 60 min. When the cardiac sympathetic nerve was denervated with 90% phenol solution, NE release further decreased in group 1. On the other hand, NE release did not decrease in group 2. These results indicate that the response to sympathetic nerve stimulation decreased in post-ischemic reperfused myocardium and this was due to diminished NE release. It was considered that sympathetic nerve conduction was not completely impaired in post-ischemic myocardium and pre-synaptic alpha-2 receptor mediated negative feedback mechanism would play an important role in these diminished NE release.


Assuntos
Doença das Coronárias/fisiopatologia , Contração Miocárdica , Reperfusão Miocárdica , Miocárdio/metabolismo , Norepinefrina/metabolismo , Função Ventricular , Animais , Doença das Coronárias/metabolismo , Cães , Sistema Nervoso Simpático/fisiologia , Ioimbina/farmacologia
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