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OBJECTIVES: The current study sought to understand the learning outcomes experienced by students and to explain their learning process in detail using interpretive data analysis. METHODS: A qualitative study examined students who participated in a multidisciplinary course in a ward. This study investigated latent meanings rather than factual information, using an interpretive paradigm. Data were collected via focus groups and analyzed using Steps for Coding and Theorization (SCAT). RESULTS: Students in the Assembly IV trial (interprofessional education in actual medical settings) experienced a process of transition from a competing (exclusive) mode to a mutual-understanding mode when communicating with people in other professions, and they acquired the perspective of an interactive (dialectic) link between involved communication (communication that attempts to connect directly with patients) and uninvolved communication (communication with patients indirectly through data and other methods) for patient communication. This enabled students to move beyond superficial communication while deepening their connections with people in other professions, complementing each other's strengths, and learning about the possibilities inherent in the provision of collaborative medical practice. CONCLUSIONS: Students participating in interprofessional education within medical settings learned about the potential to achieve a circular realization of collaborative medical practice. A circular realization of collaborative medical practice involves incorporating diverse approaches into one's own professional work via exposure to the viewpoints of other occupations and avoiding decision-making based on assumptions that are only valid within one's own profession. This process enables the discovery of better methods and perspectives and the achievement of effective medical practice by moving beyond superficial communication.
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OBJECTIVE: This study aimed to clarify the relationship between interprofessional self-evaluation and peer evaluation during interprofessional education (IPE) using team-based learning (TBL). We also aimed to clarify differences in interprofessional cooperation between students with high and low peer evaluation scores. METHODS: In total, 483 students (grades 3-5) from nine faculties at three universities participated in a TBL-based IPE program. The students completed five interprofessional self-evaluation domains (the modified Tsukuba IPE model) before and after IPE. Students also completed peer evaluation after IPE. Students were divided into three groups by peer evaluation scores (low, middle, high), and the post-class self-evaluation scores of these groups were compared using a Kruskal-Wallis test. Multiple regression analysis was also performed. Peer evaluation comments were analyzed using a qualitative inductive method. RESULTS: Students in the low peer evaluation group had significantly lower scores in the "Regarding participation in group work" domain than students in the high group (P<0.05). Students in the high group received positive comments, such as [good communication] and [working cooperatively], whereas students in the low group were required to improve in two areas: [speaking up more] and [need more communication]. CONCLUSIONS: There was a significant relationship between peer evaluation by team members and self-evaluation for "Regarding participation in group work." Students with high peer evaluation scores participated with active attitudes, whereas students with low scores were considered passive. This study suggested that using peer evaluation may enhance students' professional cooperation by improving their communication and attitudes toward active participation.
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2,4-Diamino-6-hydroxypyrimidine (DAHP) is considered a specific inhibitor of BH(4) biosynthesis and is widely used in order to elucidate the possible biological function of BH(4) in various cells. In the present study, we found that both the synthesis of tetrahydrobiopterin (BH(4)) and expression of vascular cell adhesion molecule 1 (VCAM-1) were increased in human umbilical vein endothelial cells (HUVEC) treated with proinflammatory cytokines. Thus we examined the effects of DAHP to clarify whether BH(4) might be involved in the expression of VCAM-1 in HUVEC. DAHP reduced the levels of both BH(4) and VCAM-1 induced by TNF-alpha and IFN-gamma. However, the dose-response curves of DAHP for the suppression of the VCAM-1 level and that of BH(4) level were markedly different. Supplementation with sepiapterin failed to restore the depressed VCAM-1 level, although it completely restored the BH(4) level. Furthermore, DAHP significantly reduced the VCAM-1 level under the experimental conditions using TNF-alpha alone, which failed to induce BH(4) production. Taken together, these results indicate that DAHP inhibited the expression of VCAM-1 in a BH(4)-independent manner in HUVEC. In the present study, we also found that DAHP significantly suppressed the accumulation of cytokine-induced NF-kappaB (p65) in the nucleus as well as the mRNA levels of VCAM-1 and GTP cyclohydrolase I (GTPCH), the rate-limiting enzyme of BH(4) synthesis. The data obtained in this study suggest that DAHP reduced VCAM-1 and GTPCH protein synthesis at least partially via suppressing the NF-kappaB level in the nucleus of HUVEC.
Assuntos
Biopterinas/análogos & derivados , Células Endoteliais/efeitos dos fármacos , Endotélio Vascular/citologia , Hipoxantinas/farmacologia , Molécula 1 de Adesão de Célula Vascular/metabolismo , Biopterinas/análise , Biopterinas/biossíntese , Células Cultivadas , Citocinas/farmacologia , Relação Dose-Resposta a Droga , Células Endoteliais/metabolismo , Endotélio Vascular/metabolismo , GTP Cicloidrolase/análise , GTP Cicloidrolase/biossíntese , Humanos , Interferon gama/farmacologia , Cinética , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/farmacologia , Transfecção , Fator de Necrose Tumoral alfa/farmacologia , Veias Umbilicais/citologiaRESUMO
A 46-year-old man was admitted for further evaluation of exertional chest discomfort. One family member had experienced sudden death, and 2 others had died of heart failure, including 1 known to have had Fabry's disease. The patient was also diagnosed with Fabry's disease, based on reduced leukocyte alpha-galactosidase A activity, 2.0 nmol/mg protein/hour, as well as endomyocardial biopsy findings of marked sarcoplasmic vacuolization of cardiac muscle cells by light microscopy and lamellated "zebra bodies'' in the cytoplasm shown by electron microscopy. Echocardiography disclosed marked left ventricular hypertrophy and systolic anterior motion of the mitral leaflets. On cardiac catheterization, a left ventricular peak systolic outflow gradient of 50 mm Hg was noted; this decreased to 10 mm Hg following intravenous administration of 100 mg of cibenzoline. It is imperative to recognize the existence of cases with Fabry's disease associated with left ventricular outflow obstruction.
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Antiarrítmicos/uso terapêutico , Doença de Fabry/complicações , Imidazóis/uso terapêutico , Obstrução do Fluxo Ventricular Externo/tratamento farmacológico , Biópsia , Ecocardiografia , Doença de Fabry/patologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução do Fluxo Ventricular Externo/complicações , Obstrução do Fluxo Ventricular Externo/diagnósticoRESUMO
BACKGROUND: Tetrahydrobiopterin (BH4) is an essential cofactor of nitric oxide synthase, and GTP cyclohydrolase I (GCHI) is a rate-limiting enzyme in the biosynthesis of BH4. The expression of inducible nitric oxide synthase (iNOS) was earlier demonstrated in the ventricles of patients with dilated cardiomyopathy (DCM) although that of GCHI was not clarified. The present study was designed to determine the GCHI mRNA expression as well as to confirm iNOS mRNA expression in endomyocardial biopsy specimens from patients with DCM. METHODS: Clinical details were assessed in 19 patients with DCM and in 9 control subjects. The real-time reverse transcription polymerase chain reaction (PCR) was performed on total RNA extracted from endomyocardial biopsy specimens. Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) mRNA was quantified for use as an internal control. RESULTS: iNOS/GAPDH for the DCM samples was 4.8-fold greater than that for the control ones (P<0.01), whereas the GCHI/GAPDH for the DCM samples was reduced to 31.1% of the control (P<0.05). CONCLUSIONS: The increased expression of iNOS mRNA was confirmed in endomyocardial biopsy specimens from patients with DCM. The GCHI mRNA level was suppressed in these specimens.
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Cardiomiopatia Dilatada/enzimologia , GTP Cicloidrolase/genética , Miocárdio/patologia , Óxido Nítrico Sintase/genética , RNA Mensageiro/genética , Sequência de Bases , Biópsia , Cardiomiopatia Dilatada/patologia , Estudos de Casos e Controles , Primers do DNA , Humanos , Óxido Nítrico Sintase Tipo II , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
AIM: This investigation was undertaken to clarify the current status of steroid therapy for cardiac sarcoidosis in Japan. METHODS: A questionnaire survey was conducted throughout Japan concerning cases in which steroid therapy had been administered. Replies describing 52 cases (15 men, 37 women; mean age +/- SD, 59.8 +/- 14.5 years) were analyzed. RESULTS: Of the 49 patients whose New York Heart Association (NYHA) functional classification was reported, 29 (55.8%) were in class I; 13 (25.0%) class II; 4 (7.7%) class III and 3 (5.8%) class IV. The most common initial steroid dose (used in 35 cases, or 67.3%) was 30 mg/day or 60 mg on alternate days. In most cases (85.4%), this dose was continued for 1 month followed by tapering by 5 mg every 2 to 4 weeks until reaching the maintenance dose of 5 to 10 mg/day. Steroid therapy was reported to result in improvement in 54%, no change in 40%, and deterioration in 6%. CONCLUSION: This nationwide questionnaire survey indicated fairly uniform patterns of steroid therapy for cardiac sarcoidosis in Japan, with clinical improvement in over one-half of cases and possible stabilization in most others.
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Cardiomiopatias/tratamento farmacológico , Prednisolona/uso terapêutico , Sarcoidose/tratamento farmacológico , Adulto , Idoso , Cardiomiopatias/classificação , Esquema de Medicação , Feminino , Glucocorticoides/administração & dosagem , Glucocorticoides/uso terapêutico , Pesquisas sobre Atenção à Saúde , Bloqueio Cardíaco/etiologia , Humanos , Japão , Masculino , Pessoa de Meia-Idade , Prednisolona/administração & dosagem , Sarcoidose/classificaçãoRESUMO
BACKGROUND: Basal thinning of the interventricular septum (IVS) and atrioventricular block (AVB) are characteristic features of cardiac sarcoidosis. Since the conduction system passes along IVS, it has been considered that a close connection exists between basal thinning of IVS and AVB. However, neither the incidence of cases showing basal thinning of IVS nor the relation between it and AVB has been clarified. We thus investigated to elucidate these two issues. METHODS: Thirty-five patients with cardiac sarcoidosis were selected for this study and underwent echocardiographic examination. The wall thickness of IVS was measured at a site 1 cm below the aortic valve inserted point of IVS. Thickness of this site < or = 5 mm was defined as thinning. Twelve-lead and Holter electrocardiograms were obtained to determine the presence/absence and degree of AVB. RESULTS: Basal thinning of IVS was noted in 7 of the 35 patients (20%). AVB was present in 4 of these 7 (57%), and was first degree in 3 (43%) and third degree in one (14%). AVB was not present in 3 patients. Basal thinning of IVS was not apparent in 28 of the 35 patients (80%). AVB was observed in 14 of the 28 patients, 3 had first degree block, 2 had second degree block, and 9 had third degree block. AVB was not observed in 14 of the 28 patients. CONCLUSIONS: These results clarified that basal thinning of IVS is not as common as previously thought in cardiac sarcoidosis, basal thinning of IVS and the presence/absence and degree of AVB are not necessarily correlated.
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Bloqueio Cardíaco/etiologia , Bloqueio Cardíaco/patologia , Septos Cardíacos/patologia , Sarcoidose/complicações , Adulto , Idoso , Ecocardiografia , Feminino , Septos Cardíacos/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Sarcoidose/diagnóstico por imagemRESUMO
We studied the effects of cAMP on cytokine (interferon-gamma plus tumor necrosis factor-alpha)-induced stimulation of tetrahydrobiopterin (BH4) synthesis in human umbilical vein endothelial cells (HUVEC). The cytokine mixture caused a marked increase in the biosynthesis and release of BH4 by HUVEC. Dibutyryl-cAMP produced a dose-dependent inhibition of this cytokine-induced stimulation of synthesis and release of BH4 by these cells. 8-Bromo-cAMP also caused a significant inhibition, although the effects were less marked than those of dibutyryl-cAMP. Both forskolin and the stable analog of prostacyclin, iloprost, caused cAMP accumulation and a concomitant diminution of the cytokine-induced BH4 synthesis in HUVEC. Dibutyryl-cAMP and iloprost also significantly inhibited the cytokine-induced stimulation of GTP cyclohydrolase I (GCHI) activity and mRNA production. We concluded that the suppression by the cAMP messenger system of cytokine-induced stimulation of synthesis and release of BH4 by HUVEC can be attributed to the inhibition of the activity of GCHI, the rate-limiting enzyme in BH4 biosynthetic pathway, in HUVEC. The data also suggest that the cAMP-mediated reduction in the GCHI mRNA level may at least partially explain the decline in GCHI activity. It is reasoned that under inflammatory conditions, cAMP-elevating agents such as prostacyclin exert regulatory effects on circulation by inhibiting cytokine-induced synthesis and release of BH4 by HUVEC.
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Biopterinas/análogos & derivados , Biopterinas/biossíntese , AMP Cíclico/farmacologia , Endotélio Vascular/efeitos dos fármacos , Interferon gama/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Bucladesina/farmacologia , Células Cultivadas , Colforsina/farmacologia , Relação Dose-Resposta a Droga , Combinação de Medicamentos , Endotélio Vascular/metabolismo , Inibidores Enzimáticos/farmacologia , GTP Cicloidrolase/antagonistas & inibidores , GTP Cicloidrolase/biossíntese , GTP Cicloidrolase/genética , Humanos , Iloprosta/farmacologia , Recém-Nascido , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/metabolismo , Veias UmbilicaisRESUMO
AIMS: Cilostazol, a type III phosphodiesterase inhibitor, is utilized for the treatment of intermittent claudication and is considered to have the beneficial effects against the atherogenic process. In the present study, we examined the effects of cilostazol on BH(4) biosynthesis in HUVEC treated with a mixture of the pro-inflammatory cytokines IFN-γ and TNF-α. METHODS: Isolated HUVECs were grown to confluence and treated with IFN-γ (300 units/mL) and TNF-α (300 units/mL) for 16 h in order to stimulate BH(4) biosynthesis. The BH(4) levels were measured by HPLC. The mRNA expression of GTP cyclohydrolase I (GTPCH), the rate-limiting enzyme of BH(4) biosynthesis, and GTPCH feedback regulatory protein (GFRP) were quantified by real-time PCR. The GTPCH protein expression was assessed by western blot analysis. RESULTS: Cilostazol significantly reduced the BH(4) levels in cytokine-stimulated HUVEC. Cilostazol produced a concomitant increase in the cAMP levels in HUVEC. Cilostazol decreased the GTPCH activity as well as the expression of GTPCH mRNA and protein. 8-bromo-cAMP (8Br-cAMP), a cell-permeable cAMP analogue, did not reproduce the effects of cilostazol. Cilostazol did not affect the cytokine-induced inhibition of GFRP mRNA expression. CONCLUSIONS: We conclude that cilostazol inhibited cytokine-stimulated BH(4) biosynthesis via a cAMP-independent mechanism in HUVEC. Our data indicate that cilostazol reduced GTPCH activity and did so by suppressing the GTPCH protein levels.
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Biopterinas/análogos & derivados , Citocinas/farmacologia , Células Endoteliais/efeitos dos fármacos , Tetrazóis/farmacologia , Biopterinas/antagonistas & inibidores , Biopterinas/biossíntese , Células Cultivadas , Cilostazol , AMP Cíclico , Células Endoteliais/metabolismo , Fibrinolíticos , GTP Cicloidrolase/análise , Humanos , Interferon gama/farmacologia , Fator de Necrose Tumoral alfa/farmacologia , Veias Umbilicais/citologiaRESUMO
It has been reported that angiotensin converting enzyme (ACE) 2, a homologue of ACE, has direct effects on cardiac function. However, the role of ACE2 in the development of human heart failure is not fully understood. We evaluated the expression of the ACE2 gene by means of real-time RT-PCR in myocardium from 14 patients with end-stage heart failure. The amount of ACE2 mRNA positively correlated with left ventricular (LV) end-diastolic diameter (r(2)=0.56, p<0.01) but did not significantly correlate with LV ejection fraction or plasma brain natriuretic peptide levels. In conclusion, our data show that the up-regulation of the ACE2 gene in the LV myocardium of patients with severe heart failure was associated with the degree of LV dilatation and may thereby constitute an important adaptive mechanism to retard the progression of adverse LV remodeling.
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Regulação Enzimológica da Expressão Gênica , Insuficiência Cardíaca/enzimologia , Peptidil Dipeptidase A/biossíntese , Remodelação Ventricular/fisiologia , Adulto , Idoso , Enzima de Conversão de Angiotensina 2 , Biomarcadores/metabolismo , Feminino , Insuficiência Cardíaca/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/enzimologia , Miocárdio/patologiaAssuntos
Eosinofilia/sangue , Eosinofilia/diagnóstico , Eosinófilos , Contagem de Leucócitos , Miocardite/sangue , Miocardite/diagnóstico , Biomarcadores/análise , Proteínas Sanguíneas/análise , Proteínas Granulares de Eosinófilos , Eosinofilia/tratamento farmacológico , Eosinofilia/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/tratamento farmacológico , Miocardite/patologia , Prednisolona/administração & dosagem , Ribonucleases/análise , Fatores de Tempo , Resultado do TratamentoRESUMO
A 45-year-old man developed fulminant myocarditis for which ventricular assist devices (intra-aortic balloon pumping and percutaneous cardiopulmonary support) were required for hemodynamic support. Echocardiography showed left ventricular akinesis and, since no improvement was noted on the following day, immunoglobulin (70 g/day for 2 days) was added to the therapy. The left ventricular ejection fraction increased to 25% and 40% at 12 and 36 h, respectively, representing a marked improvement in wall motion within a very short period. An endomyocardial biopsy specimen revealed focal lymphomononuclear infiltrate with adjacent myocytolysis, and acute lymphocytic myocarditis was diagnosed. Two days after administration of immunoglobulin, the serum level of interleukin-6 decreased rapidly from 180 to 5.9 pg/ml. In this patient, cardiac function improved immediately after immunoglobulin administration, suggesting the usefulness of this therapy. Three years after the diagnosis the patient is in good health, with steady normal left ventricular ejection fraction. We conclude that there are cases of acute myocarditis in which high-dose intravenous immunoglobulin therapy is effective.
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Imunoglobulinas Intravenosas/administração & dosagem , Miocardite/terapia , Endocárdio/patologia , Coração Auxiliar , Humanos , Masculino , Pessoa de Meia-Idade , Miocárdio/patologia , Choque Cardiogênico/terapia , Volume SistólicoRESUMO
Transient left ventricular (LV) wall thickening is observed in patients with acute lymphocytic myocarditis. The present study was undertaken to clarify the significance of transient LV wall thickening in patients with this disease. The subjects comprised 25 patients with acute lymphocytic myocarditis. Echocardiography was used to measure the thickness of the interventricular septum (IVS) and the LV posterior wall (PW) at four time points after myocarditis onset--namely, on days 1-3, 6-8, 13-15, and 28-30--to clarify the timing and frequency of wall thickening. The 25 patients were divided into a fulminant myocarditis group (n = 14) and a nonfulminant myocarditis group (n = 11), and the relationship between LV wall thickening and myocarditis severity was investigated. Left ventricular wall thickening was greatest on days 1-3 after myocarditis onset (IVS: 13.3 +/- 3.2 mm; PW: 12.1 +/- 2.6 mm), with this finding being noted in 14 of the 25 cases (56%). By days 6-8, the thickness of IVS had virtually normalized to 10.6 +/- 1.6 mm (P < 0.0001) and that of PW to 10.2 +/- 1.4 mm (P = 0.0006). The thickness of the IVS and PW on days 1-3 after myocarditis onset were 14.6 +/- 3.7 and 13.0 +/- 2.9 mm, respectively, in the fulminant group (P = 0.014), and 11.5 +/- 0.9 and 10.9 +/- 1.4 mm, respectively, in the nonfulminant group (P = 0.039). In lymphocytic myocarditis, LV wall thickening is greatest on days 1-3 after myocarditis onset and improves to near normal by days 6-8. Such transient LV wall thickening occurs in approximately 50% of cases. Left ventricular wall thickening was more marked in the fulminant compared with the nonfulminant group.
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Ventrículos do Coração/patologia , Miocardite/patologia , Miocárdio/patologia , Doença Aguda , Adulto , Idoso , Edema Cardíaco/patologia , Feminino , Septos Cardíacos/patologia , Humanos , Linfócitos , Masculino , Pessoa de Meia-Idade , Miócitos Cardíacos/patologia , Volume Sistólico , Fatores de Tempo , Disfunção Ventricular EsquerdaRESUMO
The presence of myocardial interstitial edema in acute myocarditis (AM) leads to thickening of the ventricular wall, and conduction disturbances, such as complete atrioventricular block (CAV), also frequently develop. This study was undertaken in order to clarify the relationship between conduction disturbances and myocardial interstitial edema in AM. The subjects comprised 50 patients with acute lymphocytic myocarditis. Based on the results of echocardiographic examinations during the acute stage, the patients were divided into a hypertrophy group (n = 29) in which the sum of the thickness of the interventricular septum and left ventricular (LV) posterior wall was >or=24 mm, and a non-hypertrophy group (n = 21) in which the sum of these parameters was <24 mm. Right ventricular endomyocardial biopsies were performed in the acute stage and the degree of interstitial edema was scored histologically. Left ventricular wall thickness and QRS duration in the acute stage were 27.7 +/- 3.6 mm and 124.1 +/- 29.6 ms, respectively, in the hypertrophy group, and 19.9 +/- 2.4 mm (P < 0.001) and 98.6 +/- 21.7 ms (P < 0.01) in the non-hypertrophy group. Complete atrioventricular block was found in 13 of 29 cases (45%) in the hypertrophy group and two of 21 cases (10%) in the non-hypertrophy group (P < 0.01). Myocardial interstitial edema was scored at 1.3 +/- 0.8 points in the hypertrophy group and 0.8 +/- 0.6 points in the non-hypertrophy group (P < 0.05). Left ventricular wall thickness and QRS duration in the convalescent stage decreased to 21.1 +/- 2.6 mm (P < 0.0001) and 97.1 +/- 17.4 ms (P < 0.01) in the hypertrophy group, respectively. Only one case (4%) in the hypertrophy group continued to show CAV during the convalescent stage (P < 0.05). The results of this study suggest that myocardial interstitial edema is implicated in the conduction disturbances that occur in AM.
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Edema/complicações , Bloqueio Cardíaco/etiologia , Miocardite/complicações , Doença Aguda , Adulto , Idoso , Biópsia , Cardiomiopatia Hipertrófica/complicações , Cardiomiopatia Hipertrófica/diagnóstico por imagem , Cardiomiopatia Hipertrófica/fisiopatologia , Edema/fisiopatologia , Feminino , Bloqueio Cardíaco/fisiopatologia , Sistema de Condução Cardíaco/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/diagnóstico por imagem , Miocardite/fisiopatologia , Miocárdio/patologia , Fatores de Risco , UltrassonografiaRESUMO
Most patients with acute myocarditis manifest particular clinical signs and symptoms, including marked cardiac failure and/or a high degree of atrioventricular block on admission. However, a 78-year-old man did not have symptoms and was hospitalized as a result of abnormalities observed on an incidentally obtained electrocardiogram (ECG). Several days later, he developed cardiogenic shock and fulminant myocarditis, which required percutaneous cardiopulmonary support; however, the cardiac failure persisted and he died approximately 4 months later. The ECG showed findings similar to those of acute inferior myocardial infarction, and on left ventriculography, diffuse hypokinesis was observed most prominently in the inferoposterior wall. During autopsy, interstitial fibrosis was marked in the inferoposterior wall, with small, round, cell infiltration prominent at the same site. Clustering of these cells is a characteristic feature of chronic myocarditis.
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Eletrocardiografia , Miocardite/patologia , Miocardite/fisiopatologia , Idoso , Autopsia , Doença Crônica , Progressão da Doença , Evolução Fatal , Fibrose/patologia , Humanos , Masculino , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/patologia , Miocardite/complicações , Choque Cardiogênico/etiologia , Disfunção Ventricular Esquerda/patologiaRESUMO
Tenascin-C (TN-C) is an extracellular matrix protein that is expressed transiently in close association with tissue remodelling in various body sites. In the heart, TN-C is only present during early stages of development, is not expressed in the normal adult, but reappears in pathological states. The purpose of this study was to analyse the expression of TN-C in myocardial tissue from myocarditis patients, and to evaluate the diagnostic value of immunostaining for TN-C in the assessment of inflammatory activity in biopsy specimens. A total of 113 biopsy specimens obtained from 32 patients with a clinical diagnosis of acute myocarditis were examined by immunohistochemistry and in situ hybridization for TN-C. The immunostaining was semi-quantified and compared with histological diagnosis according to the Dallas criteria. Furthermore, serial biopsies from 22 patients were taken during convalescence, and sequential changes in TN-C levels were analysed. Expression of TN-C was specifically detected in endomyocardial biopsy specimens from patients with active-stage inflammation, and disappeared in healed stages. The degree of expression of TN-C correlated with the severity of histological lesions. These data suggest that TN-C reflects disease activity in cases of human myocarditis. Immunostaining for TN-C could enhance the sensitivity and accuracy of diagnosis using biopsy specimens.
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Miocardite/metabolismo , Tenascina/análise , Doença Aguda , Adolescente , Adulto , Idoso , Biomarcadores/análise , Biópsia , Criança , Feminino , Humanos , Imuno-Histoquímica/métodos , Hibridização In Situ , Masculino , Pessoa de Meia-Idade , Miocárdio/metabolismoRESUMO
Tetrahydrobiopterin(BH4) serves as an essential cofactor for the biosynthesis of nitric oxide (NO). BH4 is de novo synthesized from GTP and GTP cyclohydrolase I(GCH I) is the rate-limiting enzyme in the biosynthesis of BH4. Under inflammatory conditions, it is reported that endothelial cells release large amount of BH4. In this study, we examined the regulation mechanism of the biosynthesis of BH4 in human umbilical vein endothelial cells(HUVEC). Prostacyclin and forskolin, reagents of stimulation of cAMP signaling cascade, reduced cytokine induced biosynthesis of BH4 through the inhibition of expression of GCH I mRNA. On the other hand, stimulations of NO-cGMP signaling pathway inhibited GCH I activities through the post translational modification of GCH I enzyme. Both two signaling cascade lead to vasodilation. It is suggested that the biosynthesis of BH4 can be regulated by negative feed back regulation systems between endothelium and smooth muscle cells to prevent over stimulated vasodilation.
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Biopterinas/análogos & derivados , Biopterinas/biossíntese , Endotélio Vascular/fisiologia , Retroalimentação Fisiológica/fisiologia , Inflamação/fisiopatologia , Transdução de Sinais/fisiologia , Vasodilatação/fisiologia , Células Cultivadas , AMP Cíclico/fisiologia , GMP Cíclico/fisiologia , Endotélio Vascular/citologia , Epoprostenol/fisiologia , GTP Cicloidrolase/fisiologia , Humanos , Músculo Liso Vascular/citologia , Músculo Liso Vascular/fisiologia , Óxido Nítrico/fisiologia , Processamento de Proteína Pós-Traducional , Veias UmbilicaisRESUMO
It has been reported that some patients with acute myocarditis have transient ventricular thickening associated with narrowing of the left ventricular cavity caused by interstitial edema. The present study investigated this phenomenon in 20 patients with acute myocarditis. Based on the sum of the interventricular septal wall thickness and left ventricular posterior wall thickness (IVST + PWT), measured by M-mode echocardiography, patients were divided into group A (IVST + PWT >/=25 mm, n=12) and group B (IVST + PWT <25 mm, n=8). The IVST + PWT was 31.8 +/-3.5 mm in group A and 21.9+/-2.7 mm in group B (p<0.0001). The left ventricular end-diastolic dimension (LVDd) was 42.3+/-6.0 mm in group A and 49.4+/-6.7 mm in group B (p<0.05). The stroke volume (SV) was 41.1+/-20.5 ml and 73.0+/-32.3 ml in groups A and B, respectively (p<0.05). The left ventricular ejection fraction (LVEF) was similar in group A (47.9+/-13.0%) and group B (56.9+/-9.0%). The SV correlated inversely with IVST + PWT (r=-0.62, p<0.01), and directly with both the LVDd (r=0.95, p<0.0001) and LVEF (r=0.64, p<0.01). The LVDd correlated inversely with IVST + PWT (r=-0.62, p<0.01). In conclusion, the reduction in SV that occurs during the acute phase of myocarditis is not only the result of systolic dysfunction, but also of the concentric left ventricular wall thickening associated with myocardial interstitial edema, which results in narrowing of the left ventricular cavity at end diastole.
Assuntos
Ventrículos do Coração/patologia , Miocardite/fisiopatologia , Miocárdio/patologia , Volume Sistólico , Disfunção Ventricular Esquerda/fisiopatologia , Doença Aguda , Adolescente , Adulto , Idoso , Criança , Convalescença , Diástole , Edema/etiologia , Feminino , Septos Cardíacos/patologia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Miocardite/complicações , Miocardite/diagnóstico por imagem , Miocardite/patologia , Estudos Retrospectivos , Ultrassonografia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/patologiaRESUMO
In many cases, the diagnosis of eosinophilic myocarditis is suggested by an elevated peripheral blood eosinophil count. However, no detailed studies have been performed on the sequential changes in the initial peripheral blood eosinophil count over the course of the disease. We measured the peripheral blood eosinophil count at the time of presentation in eight patients with eosinophilic myocarditis proven by endomyocardial biopsy and intermittently thereafter. The eosinophil count at the time of onset was <500/mm(3) in four patients, >500/mm(3) but <1,000/mm(3) in three patients, and > or =1,000/mm(3) in one patient. In three of the four patients with an initial eosinophil count of <500/mm(3), an increase to > or =500/mm(3) occurred 7-12 days after the onset. The remaining patient did not develop peripheral eosinophilia. In conclusion, in the early stage of eosinophilic myocarditis, peripheral hypereosinophilia is not present initially in some patients, and may not develop during the course of the illness in a subset of these patients.