RESUMO
The antiphospholipid syndrome (APS) is an acquired thrombophilia, considered a systemic autoimmune disorder. We report a patient with APS who presented multiple cerebral infarcts (stroke) as a complication of a thrombotic non bacterial endocarditis. We review the literature focused on the physiological mechanism that produce this disease and its complications. Clinical features and their prognostic value and the different therapeutic options were also studied.
Assuntos
Síndrome Antifosfolipídica/complicações , Endocardite/complicações , Acidente Vascular Cerebral/etiologia , Trombose/etiologia , Adulto , Feminino , HumanosRESUMO
AIM: The aim of this paper was to evaluate the hemodynamic behavior of carotid kinking, as assessed by color Doppler ultrasonography at baseline and during neck movements, and their relation to neurological symptoms. METHODS: In this cross-sectional study, 60 consecutive patients with non-atheromatous carotid kinking in whom diagnostic color Doppler ultrasonography investigation of neck vessels had been requested for clinical suspicion of atherosclerotic disease were evaluated. To evaluate if there were significant changes of blood velocities as a consequence of kinking, for each carotid artery we recorded systolic and diastolic velocities both in the segments proximal to kinking, as well as intra-kinking. The effects of postural changes and neck movements on carotid blood flow were also studied. RESULTS: Flow in carotid arteries with kinking was always normal, and no differences were found between flow velocity measured at the level of kinking compared to the normal tract of the vessel. During head rotation tests, flow remained largely unaffected, a substantial reduction in the velocities in the ophthalmic artery was found in 13.5% of the cases, while an increase was recorded in 27%; and no symptoms or events were recorded during the study. None of the patients referred symptoms, nor were neurological events or signs detected during the maneuvers. CONCLUSION: Our results show that carotid kinks are not a mechanism of acute cerebral ischemia, and therefore are unlikely to be a cause of neurological events or symptoms.
Assuntos
Isquemia Encefálica/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Circulação Cerebrovascular , Movimentos da Cabeça , Hemodinâmica , Ultrassonografia Doppler em Cores , Doença Aguda , Idoso , Argentina , Velocidade do Fluxo Sanguíneo , Isquemia Encefálica/etiologia , Isquemia Encefálica/fisiopatologia , Artérias Carótidas/fisiopatologia , Distribuição de Qui-Quadrado , Estudos Transversais , Feminino , Humanos , Itália , Masculino , Pescoço , Postura , Valor Preditivo dos Testes , Fluxo Sanguíneo Regional , RotaçãoRESUMO
Titanium powder production by the hydride-dehydride method has been developed as a non-expensive process. In this work, commercially pure grade two Ti specimens were hydrogenated. The hydrided material was milled in a planetary mill. The hydrided titanium powder was dehydrided and then sieved to obtain a particle size between 37 and 125 microm in order to compare it with a commercial powder produced by chemical reduction with a particle size lower than 150 microm. Cylindrical green compacts were obtained by uniaxial pressing of the powders at 343 MPa and sintering in vacuum. The powders and the density of sintered compacts were characterized, the oxygen content was measured and in vivo tests were performed in the tibia bones of Wistar rats in order to evaluate their biocompatibility. No differences were observed between the materials which were produced either with powders obtained by the hydride-dehydride method or with commercial powders produced by chemical reduction regarding modifications in compactation, sintering and biological behaviour.
Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Tíbia/citologia , Tíbia/efeitos dos fármacos , Titânio/química , Titânio/farmacologia , Animais , Cristalização/métodos , Masculino , Teste de Materiais , Tamanho da Partícula , Pós , Ratos , Ratos Wistar , Propriedades de SuperfícieRESUMO
INTRODUCTION: Pig islet xenotransplantation represents an attractive way to solve our human organ shortage. In this preclinical protocol, we implanted adult porcine islets microencapsulated in alginate-polylysin into insulin-dependent diabetic dogs. METHODS: Pancreata were obtained from animals weighing 100 to 150 kg in a slaughterhouse. The islets were isolated by collagenase digestion. The encapsulation technique was a modification of Sun's method. Isolated islets (5000 islet equivalents per kilogram of dog weight) were mixed with 1.6% low-viscocity alginate. Microcapsules were cultured for 36 hours before implantation. The five dogs were in healthy prior to induction of diabetes mellitus at least 1 year prior. Under sedation, we implanted microcapsules. We performed determinations of peripheral blood insulin at baseline and every 3 months as well as glycosylated hemoglobin at baseline and every 4 months. During follow-up, glycemia was estimated twice a day at 3 hours after morning and night meals using a blood glucose monitoring system. RESULTS: We observed significant decrease (20%-80%) in insulin needs (P < .01). Of note, before the procedure no hormone was detected in the blood at 6 to 12 months after transplantation, plasma insulin had improved significantly (P < .05) and glycosylated hemoglobin also showed a significant decrease (P < .01). All owners subjectively claimed that their animals were enjoying a better quality of life. DISCUSSION: Our preliminary data suggested that pig islet microencapsulation achieved metabolic control in type I diabetic dogs without the risk of immunosuppression using one or two procedures per year.
Assuntos
Diabetes Mellitus/cirurgia , Diabetes Mellitus/veterinária , Doenças do Cão/cirurgia , Insulina/metabolismo , Transplante das Ilhotas Pancreáticas/métodos , Transplante Heterólogo/métodos , Animais , Glicemia/metabolismo , Cápsulas , Técnicas de Cultura de Células , Diabetes Mellitus/sangue , Diabetes Mellitus/tratamento farmacológico , Doenças do Cão/sangue , Doenças do Cão/tratamento farmacológico , Cães , Sobrevivência de Enxerto , Insulina/sangue , Insulina/uso terapêutico , Secreção de Insulina , SuínosRESUMO
We examined antioxidant actions in 73 patients undergoing coronary artery surgery by assessing mitochondrial damage and oxidative stress in ventricular biopsies obtained at preischemia and postreperfusion. Those patients who received antioxidant therapy benefited by less oxidative stress and mitochondrial damage.
Assuntos
Antioxidantes/uso terapêutico , Ponte de Artéria Coronária/efeitos adversos , Mitocôndrias/patologia , Estresse Oxidativo , Complicações Pós-Operatórias/prevenção & controle , Humanos , Pessoa de Meia-Idade , Complicações Pós-Operatórias/patologiaRESUMO
Atherosclerosis is the most frequent cause of death in industrialized countries. Lesions are characterized by lipid deposits, focal thickening of the arterial wall with proliferation of smooth muscle cells (SMC), mononuclear infiltrates and neoformed vessels. In this paper, we studied the proliferative characteristics and cytogenetic alterations of SMC. These cells, expressing specific muscular actin, were diploid with an increased proliferative index for PCNA. A high percentage of SMC showed intense expression of p53. There were signs of chromosomal instability, being the most frequent findings chromosome 7 trisomy and chromosome 11 monosomy. Additionally, the gene for FGF-3 showed a marked amplification. These findings strongly suggest that SMC proliferation is active, and is related to the accumulation or mutation of the p53 oncoprotein. It also presents specific chromosomal alterations in close relation with growth factors. According to these findings SMC hyperplasia in the atherosclerosis plaque may be considered as a cellular clonal expansion.
Assuntos
Arteriosclerose/genética , Cromossomos Humanos 6-12 e X/genética , Músculo Liso , Proteínas Nucleares/genética , Arteriosclerose/patologia , Cromossomos Humanos Par 11/metabolismo , Cromossomos Humanos Par 7/genética , Fator 3 de Crescimento de Fibroblastos , Fatores de Crescimento de Fibroblastos/genética , Humanos , Hibridização in Situ Fluorescente , Músculo Liso/patologia , Proteínas Proto-Oncogênicas/genética , Trissomia , Proteína Supressora de Tumor p53/genéticaRESUMO
Atherosclerosis is the most frequent cause of death in industrialized countries. Lesions are characterized by lipid deposits, focal thickening of the arterial wall with proliferation of smooth muscle cells (SMC), mononuclear infiltrates and neoformed vessels. In this paper, we studied the proliferative characteristics and cytogenetic alterations of SMC. These cells, expressing specific muscular actin, were diploid with an increased proliferative index for PCNA. A high percentage of SMC showed intense expression of p53. There were signs of chromosomal instability, being the most frequent findings chromosome 7 trisomy and chromosome 11 monosomy. Additionally, the gene for FGF-3 showed a marked amplification. These findings strongly suggest that SMC proliferation is active, and is related to the accumulation or mutation of the p53 oncoprotein. It also presents specific chromosomal alterations in close relation with growth factors. According to these findings SMC hyperplasia in the atherosclerosis plaque may be considered as a cellular clonal expansion.
RESUMO
BACKGROUND: A complete immunohistochemical characterization in complicated carotid plaques is still lacking. The cellular components of 165 carotid endarterectomy specimens were analyzed to assess their role in the pathogenesis of plaque rupture and intraplaque hemorrhage without rupture. METHODS AND RESULTS: The fibrous caps at the sites of plaque rupture showed CD68+ macrophages, T-lymphocytes, and scarce B-lymphocytes. Ruptured plaques showed mononuclear infiltrates in the caps, shoulders, and bases of the plaques in 85% of the cases. Only 46% of nonruptured plaques showed such infiltrates (P <.0001). Two types of lipid cores were recognized: avascular or mildly vascularized and highly vascularized. The vessels of the latter type reacted with CD31 and CD34. In 57.5% of the cases, the base and the shoulders of the plaques showed neoformed, CD34+ vessels, often surrounded by mononuclear infiltrates. Intraplaque hemorrhage without rupture had highly vascularized lipid cores in all cases. T-lymphocytes and macrophages were in close contact with neoformed vessels. CONCLUSIONS: Plaque rupture is characterized by mononuclear cell infiltration of the caps, whereas intraplaque hemorrhage without rupture is characterized by extensive vascularization of the plaque.
Assuntos
Artérias Carótidas/patologia , Estenose das Carótidas/patologia , Imunofenotipagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos Monoclonais , Especificidade de Anticorpos , Artérias Carótidas/imunologia , Artéria Carótida Externa/imunologia , Artéria Carótida Externa/patologia , Artéria Carótida Interna/imunologia , Artéria Carótida Interna/patologia , Estenose das Carótidas/imunologia , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
As more effective therapies have produced longer survival times for human immunodeficiency virus (HIV)-infected patients, new complications of late-stage HIV infection including HIV-related heart disease have emerged. Almost any agent that can cause disseminated infection in patients with acquired immunodeficiency syndrome (AIDS) may involve myocardium, but clinical evidence of cardiac disease is usually overshadowed by manifestations in other organs, primarily the brain and lungs. Cardiac abnormalities are found at autopsy in two-thirds of patients with AIDS, and more than 150 reports of cardiac complications have been published. Cardiac involvement in HIV disease includes pericardial effusion, myocarditis, dilated cardiomyopathy, and/or endocardial involvement at any stage of the disease. This review deals with all the cardiac manifestations of AIDS and serves to highlight two problems and one indication. First of all, there are very few clinical studies. Current knowledge is based almost exclusively on echocardiography and autopsy studies. Observational or clinical trials would be useful. Second, there exists very poor information on the impact of treatment; and epidemiologic and clinicopathologic studies are mandatory for obtaining detailed data concerning the mechanisms of myocardial damage in AIDS. Finally, because cardiac complications are often clinically inapparent or subtle in the initial stages, periodic screening of HIV-positive patients by electrocardiogram and echocardiogram is probably indicated. In addition, AIDS may also provide the opportunity to gain insights into the pathogenesis of little understood cardiac diseases such as lymphocytic myocarditis and dilated cardiomyopathy.
Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Cardiopatias/etiologia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Biópsia , Diagnóstico Diferencial , Ecocardiografia , Eletrocardiografia , Cardiopatias/diagnóstico , Cardiopatias/epidemiologia , Humanos , Incidência , Taxa de SobrevidaRESUMO
This review deals with tobacco-associated cardiovascular effects and diseases. The importance of tabaccoism in primary care, its effects on cardiovascular, and immunology system and hemostasia, as well as, the role of smoking in atherosclerosis, coronary heart disease, acute myocardial infarct, diabetes, and other alterations are discussed. Finally we summarize the general tobacco control policies and the methods to achieve smoking cessation. Although it is well established the causal relationship between smoking and disease, and the general public is aware of this, the cardiologist's involvement and commitment is of utmost importance.
Assuntos
Doenças Cardiovasculares/induzido quimicamente , Fumar/efeitos adversos , Argentina/epidemiologia , Cardiologia , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/mortalidade , Humanos , Morbidade , Papel do MédicoRESUMO
Although there are many publications on the usefulness of magneto-therapy, discrepancies exist about the utility of electromagnetic fields in skin wound healing. The objective of this work was to study the effect of electromagnetic fields on wound healing in rats. Thirty six male Wistar rats were used; a rectangular lesion was made in the back of each animal (4.2 cm x 2.3 cm). They were divided into 3 groups: group C (control) with sham treatment; group C50, treated with continuous electromagnetic fields of 5 mT (50 Gauss) and group P200, treated with pulsed electromagnetic fields of 20 mT (200 G). The treatments were of 30 minutes a day during 21 days. The corporal weights (Table 1) and the wound longitudinal and transversal maximal axis (Figures 1, 2) were weekly recorded and the data was evaluated by analysis of variance. On day 14, the P200 group showed the maximal longitudinal axis which was smaller than that of group C (p < 0.01). On day 21 in both treated groups the maximal longitudinal axis was smaller than that of group C (p < 0.01); besides the axis was smaller in the P200 group than in the C50 group (p < 0.05). No statistical differences were observed in the remaining data. The results showed a facilitating effect of electromagnetic fields on wound healing in rats. Pulsed electromagnetic fields seem to have a precocious and larger healing effect than continuous electromagnetic fields.
Assuntos
Campos Eletromagnéticos , Pele/lesões , Cicatrização , Animais , Peso Corporal , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar , Fatores de TempoRESUMO
INTRODUCTION AND OBJECTIVES: The myocardial damage during ischemia and reperfusion in the rabbit was studied, in order to compare two different models: the occlusion of the circumflex coronary artery (Cx) vs the occlusion of the left anterior descending coronary artery (LAD). METHODS: Each group consisted of 10 New Zealand rabbits; after 50 minutes of occlusion the artery was reopened for 20 minutes and then a biopsy from the area at risk and another from the perfused area were obtained. The specimens were used for chemiluminiscence and electron microscopy. Electrocardiograms were taken throughout the experience. Transverse sections of both ventricles were used for light microscopy. RESULTS: In both groups elevations of the ST segment, more important in the Cx group (p < 0.001) were observed. In the LAD group, the QRS complexes were enlarged in three animals, in 4 rabbits there were reperfusion arrhythmias, but the experimental mortality was zero. In the other group, 50% of the animals died during the experiment. In the LAD group the chemiluminiscence of the area at risk was greater than that of the perfused area (p < 0.001). No differences could be demonstrated between the samples of the Cx group, probably because of the extensive necrotic areas unable to generate photoemission. Ultrastructural and microscopic characteristic lesions of the ischemia-reperfusion phenomena were found in both groups, particularly severe in the Cx group with extensive areas of necrotic tissue. CONCLUSIONS: This experience shows that the myocardial necrosis, the mortality and the malignant arrhythmias were quantitatively different according to which coronary artery was occluded. This fact may be taken into account when an animal model for ischemia-reperfusion is selected.
Assuntos
Doença das Coronárias/fisiopatologia , Traumatismo por Reperfusão , Animais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Doença das Coronárias/cirurgia , Eletrocardiografia , Miocárdio/patologia , Miocárdio/ultraestrutura , Necrose , Coelhos , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/fisiopatologiaRESUMO
Cloricromene (Clo) has been used to prevent myocardial damage after transient occlusion of the circumflex coronary artery (Cx). Twenty rabbits were injected for 4 days with a single dose of Clo (0.25 mg/kg i.v.) or placebo. On the 5th day, the Cx was occluded, and Clo (6.4 micrograms/kg/min) or placebo was continuously infused. After 50 min, the occlusion was removed and after 20 min of reperfusion, the rabbits were sacrificed. In the placebo group, all rabbits showed marked ST segment changes and severe ischemic arrhythmias (6/10 animals). In 5 of them, ventricular fibrillation was followed by death. In the Clo group smaller ST segment elevations were observed, and in 2 rabbits ventricular fibrillation spontaneously reversed as did ST segment elevations. A significant reduction of the necrotic area was also observed in the Clo group by postmortem examination.
Assuntos
Cromonar/análogos & derivados , Traumatismo por Reperfusão Miocárdica/prevenção & controle , Animais , Cromonar/uso terapêutico , Eletrocardiografia , Microscopia Eletrônica , Isquemia Miocárdica/fisiopatologia , Traumatismo por Reperfusão Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/fisiopatologia , Miocárdio/ultraestrutura , CoelhosRESUMO
The american primate Cebus apella has been used as an experimental model for the study of acute and chronic Chagas' disease. The antibody response elicited by 4 x 10(6) blood trypnomastigotes injected into four monkeys was analysed. Peak titres of IgM and IgG of anti-Trypanosoma cruzi antibodies were found at day 22, and between days 20 and 40 post-infection (p.i.), respectively. The ability of a Mr 37kDa (T37K) glycoprotein purified from T. cruzi epimastigotes to generate IgG anti-T. cruzi antibodies in monkeys, and protect them against a challenge with trypomastigotes, was also studied. Monkeys non-immunized with T37K reached peak values of parasitaemia between days 18 and 21 post-infection, whereas immunized monkeys had lower parasitaemias without important variation. Anti-T37K antibodies in immunized monkeys decreased from day 2 with the lowest titres between days 14 to 22 p.i., coincident with the peak of parasitaemia in control non-immunized monkeys. These results suggest that anti-T37K antibodies could be responsible for the low parasitaemia detected in immunized monkeys.
Assuntos
Anticorpos Antiprotozoários/biossíntese , Antígenos de Protozoários/imunologia , Doença de Chagas/imunologia , Trypanosoma cruzi/imunologia , Animais , Anticorpos Antiprotozoários/imunologia , Cebus , Doença de Chagas/prevenção & controle , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Imunoglobulina G/biossíntese , Imunoglobulina M/biossíntese , Masculino , Vacinas Protozoárias/imunologia , Fatores de Tempo , VacinaçãoRESUMO
The objective was to study the secretory pattern, both basal and stimulated either by histamine (0.1 mg/kg) or pentagastrin (64 micrograms/kg) in eighteen Cebus apella monkeys chronically infected with different T. cruzi strains (CA1, n = 10; Colombian, n = 4 and Tulahuen, n = 4) and to describe the morphological findings in the gastrointestinal tract in twelve infected (6 sacrificed and 6 spontaneously dead) and four healthy monkeys. All infected monkeys and 35 healthy ones were evaluated by contrast X-ray examination. No differences were observed in basal acid output between control and infected groups. Animals infected with the Tulahuen and Colombian strains showed significant lower values of peak acid output in response to histamine or pentagastrin (p < 0.01 and p < 0.05 respectively; "t" test) in comparison to the controls. Barium contrast studies showed enlargement and dilatation of the colon in three infected animals. Histopathological lesions were seen in 75% of the autopsied animals either in colon alone (33%) or both, in colon and esophagus (42%). The normal secretion observed in the CA1 infected group could be due to a lower virulence of the strain, a lower esophageal tropism or the necessity of a longer post-infection time to cause lesions.
Assuntos
Cebus/fisiologia , Doença de Chagas/fisiopatologia , Modelos Animais de Doenças , Ácido Gástrico/metabolismo , Animais , Doença de Chagas/diagnóstico por imagem , Doença de Chagas/patologia , Doença Crônica , Sistema Digestório/patologia , Feminino , Histamina/farmacologia , Masculino , Pentagastrina/farmacologia , Radiografia , Estimulação QuímicaRESUMO
Two neoplasms were observed in two feral male Cebus apella monkeys of approximately 12 and 14 years of age. Histologically, the tumors were well-differentiated squamous cell carcinomas, one affecting the soft and hard palates reaching the nasal cavity and the other involving the oral cavity floor and the inferior maxillar.
Assuntos
Carcinoma de Células Escamosas/veterinária , Cebus , Doenças dos Macacos/patologia , Neoplasias Bucais/veterinária , Animais , Carcinoma de Células Escamosas/patologia , Masculino , Neoplasias Bucais/patologiaRESUMO
Cloricromene, a compound with several biological activities which suggest a therapeutic role in thrombosis or ischemic disease, has been studied for its effects on the extension of myocardial damage and the production of oxygen free radicals during periods of ischemia and reperfusion. In twenty rabbits the left anterior descending coronary artery (LAD) was occluded and cloricromene (3.6 micrograms/kg/min; n = 10) or placebo (n = 10) were continuously infused. After 50 min the artery was reopened and after 20 min of reperfusion a biopsy was obtained from the anterior wall of the heart in the LAD area and from the posterior wall (control myocardium) prior to sacrifice. Both samples were used for chemiluminescence measurement (free-radical production) and ultrastructural studies. In the placebo group all rabbits showed ST-segment changes during ischemia and reperfusion arrhythmias, while in the cloricromene group there were transient ST elevations in 4 animals which reverted at higher infusion rates of the drug. The chemiluminescence values were 18,017 +/- 1,956 and 8,583 +/- 918 cpm/mg protein (p < 0.001) in the anterior and posterior walls of the left ventricle, respectively, for the placebo group, and 7,767 +/- 992 and 8,333 +/- 832 cpm/mg protein (NS), respectively, for the cloricromene group. The ratio between the anterior and posterior wall was 2.27 +/- 0.37 for the placebo group versus 0.95 +/- 0.11 for the cloricromene group (p < 0.001). In ultrastructural studies, the anterior wall in the placebo group showed irreversible myocyte injury and infarction as well as mitochondrial damage. Samples from the cloricromene-treated group showed, in general, preservation of myocyte architecture or minor signs of injury. These results illustrate clearly the protective effect of cloricromene during damage induced by ischemia and reperfusion in the rabbit.
Assuntos
Cromonar/análogos & derivados , Infarto do Miocárdio/patologia , Isquemia Miocárdica/patologia , Traumatismo por Reperfusão Miocárdica/patologia , Animais , Cromonar/farmacologia , Circulação Coronária/efeitos dos fármacos , Eletrocardiografia/efeitos dos fármacos , Medições Luminescentes , Microscopia Eletrônica , Mitocôndrias Cardíacas/efeitos dos fármacos , Mitocôndrias Cardíacas/ultraestrutura , Dilatação Mitocondrial/efeitos dos fármacos , Miocárdio/patologia , CoelhosRESUMO
PURPOSE: To evaluate electrocardiographic data of Cebus apella monkeys with Chagas' disease. MATERIAL AND METHODS: 53 Cebus apella monkeys (juvenile and adult of both sexes) were used: 35 as a control group and 18 inoculated four-five years ago with 3 different Trypanosoma cruzi strains (CA1, n = 10; Colombian, n = 4; Tulahuen, n = 4). RESULTS: The normal electrocardiogram (ECG) showed differences with that of man, a) high cardiac rate; b) presence of "pulmonary p" wave without pulmonary pathology. The ECT alterations found between 11 and 58 months after last inoculation were: right bundle branch block; intermittent right bundle branch block; left ventricle overload; repolarization disturbances; left anterior hemiblock; extra systole. These alterations resemble those found in humans, as well as clinical parasitological and immunological alterations. Their incidence and the time at which they appeared, seem to vary according to the route, strain, inoculum and frequency of the inoculation. Three of the monkeys died spontaneously 46, 48 and 52 months after the infections due to the natural evolution of the disease, and six were sacrificed during the follow-up. In both cases histopathological lesions were found, and their intensity was directly related to the time and resembled the human disease. CONCLUSION: The Cebus apella, as it reproduces human electrocardiographic and histopathological alterations, a short time after experimental infection, is a suitable model for the study of the different aspects of the physiopathology, immunopathology and therapeutics of the indeterminate and chronic phases of Chagas' disease.