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1.
Mol Hum Reprod ; 27(6)2021 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-33983443

RESUMO

Endometriosis is characterised by inflammation and fibrotic changes. Our previous study using a mouse model showed that proinflammatory factors present in peritoneal haemorrhage exacerbated inflammation in endometriosis-like grafts, at least in part through the activation of prostaglandin (PG) E2 receptor and protease-activated receptor (PAR). In addition, hypoxia is a well-known inducer of fibrosis that may be associated with epithelial-mesenchymal transition (EMT). However, the complex molecular interactions between hypoxia and proinflammatory menstruation-related factors, PGE2 and thrombin, a PAR1 agonist, on EMT in endometriosis have not been fully characterised. To explore the effects of hypoxia and proinflammatory factors on EMT-like changes in endometrial cells, we determined the effects of PGE2 and thrombin (P/T) on EMT marker expression and cell migration in three dimensional cultured human endometrial epithelial cells (EECs) and endometrial stromal cells (ESCs). Treatment of EECs with P/T under hypoxia stimulated cell migration, increased the expression of mesenchymal N-cadherin, vimentin and C-X-C chemokine receptor type 4 (CXCR4), and reduced the expression of epithelial E-cadherin. Furthermore, treatment with C-X-C motif chemokine ligand 12 (CXCL12), a ligand for CXCR4, increased EMT marker expression and cell migration. In ESCs, P/T or oestrogen treatment under hypoxic conditions increased the expression and secretion of CXCL12. Taken together, our data show that hypoxic and proinflammatory stimuli induce EMT, cell migration and inflammation in EECs, which was increased by CXCL12 derived from ESCs. These data imply that inflammatory mediators in retrograde menstrual fluid contribute to ectopic endometrial EMT and migration in the presence of peritoneal hypoxia.


Assuntos
Hipóxia Celular , Endometriose/etiologia , Endométrio/patologia , Transição Epitelial-Mesenquimal , Distúrbios Menstruais/patologia , Menstruação/fisiologia , Adulto , Biomarcadores , Técnicas de Cultura de Células em Três Dimensões , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Quimiocina CXCL12/metabolismo , Quimiocina CXCL12/farmacologia , Dinoprostona/farmacologia , Endometriose/patologia , Endométrio/metabolismo , Células Epiteliais/efeitos dos fármacos , Estradiol/farmacologia , Feminino , Expressão Gênica , Humanos , Inflamação , Mediadores da Inflamação/metabolismo , Distúrbios Menstruais/metabolismo , Esferoides Celulares , Células Estromais/efeitos dos fármacos , Trombina/farmacologia
2.
Osteoporos Int ; 32(4): 671-680, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32968889

RESUMO

The effects of the age at estrogen replacement therapy (ERT) initiation on bone quality in Turner syndrome were evaluated using trabecular bone score. Early puberty ERT positively correlated with increase in bone quality. Early initiation of ERT is necessary for the acquisition of bone quality as well as bone density. INTRODUCTION: Studies have reported associations between bone mineral density and estrogen replacement therapy (ERT) in Turner syndrome (TS) patients; however, few studies exist on the effect on bone quality. The aim of this study was to evaluate the effects of the age at ERT initiation on bone quality of Japanese TS patients, cross-sectionally and longitudinally. METHODS: Cross-sectionally, 95 TS patients were divided into three groups based on their age at initiation of ERT: A (12-14 years, 11 patients), B (15-17 years, 47 patients), and C (over 18 years, 37 patients). To assess bone quality, trabecular bone score (TBS) was used. The effects of age at initiation and duration of ERT on TBS were examined using multiple regression analysis. In the longitudinal study, 48 patients who underwent dual-energy X-ray absorptiometry multiple times were divided into three groups: D (12-14 years, 8 patients), E (15-17 years, 18 patients), and F (over 18 years, 22 patients). Each group was analyzed for the rate of change in TBS per year. RESULTS: Cross-sectionally, the TBS showed significant differences among the three groups (TBS A, 1.302; B, 1.299; C, 1.245) (p = 0.013); group C was significantly lower than B (p = 0.014); bone quality was degraded. Multiple regression analysis revealed that age at ERT initiation significantly affected the increase in TBS (p = 0.002). Longitudinally, the rate of change of TBS was not significantly different in the three groups (p = 0.73). CONCLUSION: Early initiation of ERT may have positive effects on bone quality in TS. Large prospective studies will be needed.


Assuntos
Osso Esponjoso , Síndrome de Turner , Absorciometria de Fóton , Adulto , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Terapia de Reposição de Estrogênios , Feminino , Humanos , Japão , Estudos Longitudinais , Vértebras Lombares , Estudos Prospectivos , Síndrome de Turner/tratamento farmacológico
3.
Scand J Med Sci Sports ; 28(4): 1339-1344, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29247985

RESUMO

To examine the effect of a 12-week slow movement resistance training using body weight as a load (SRT-BW) on muscle mass, strength, and fat distribution in healthy elderly people. Fifty-three men and 35 women aged 70 years old or older without experience in resistance training participated, and they were randomly assigned to a SRT-BW group or control group. The control group did not receive any intervention, but participants in this group underwent a repeat measurement 12 weeks later. The SRT-BW program consisted of 3 different exercises (squat, tabletop push-up, and sit-up), which were designed to stimulate anterior major muscles. Initially, these exercises were performed by 2 sets of 10 repetitions, and subsequently, the number of repetitions was increased progressively by 2 repetitions every 4 weeks. Participants were instructed to perform each eccentric and concentric phase of movement slowly (spending 4 seconds on each movement), covering the full range of motion. We evaluated muscle mass, strength, and fat distribution at baseline and after 12 weeks of training. Changes over 12 weeks were significantly greater in the SRT-BW group than in the control group, with a decrease in waist circumference, hip circumference, and abdominal preperitoneal and subcutaneous fat thickness, and an increase in thigh muscle thickness, knee extension strength, and hip flexion strength. In conclusion, relatively short-term SRT-BW was effective in improving muscle mass, strength, and fat distribution in healthy elderly people.


Assuntos
Força Muscular , Músculo Esquelético/fisiologia , Treinamento Resistido/métodos , Gordura Abdominal , Idoso , Distribuição da Gordura Corporal , Peso Corporal , Feminino , Humanos , Masculino , Amplitude de Movimento Articular , Sarcopenia/prevenção & controle , Gordura Subcutânea , Circunferência da Cintura
4.
Environ Toxicol ; 28(1): 21-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21384493

RESUMO

Chlorinated benz[a]anthracenes (Cl-BaA) are halogenated aromatic compounds (typified by dioxins) found in the environment at relatively high concentrations. Fischer 344 rats were intragastrically administered 0, 1, or 10 mg of Cl-BaA or its parent compound benz[a]anthracene (BaA) per kg of body weight for 14 consecutive days. Both chemicals at 10 mg/kg/day inhibited the gain in body weight, and consequent increase in relative liver weight. Hepatic gene expression of cytochrome P450 (CYP) 1A1, 1A2, and 1B1 was significantly stimulated by administration of BaA (10 mg/kg/day) compared with the control. After administration of Cl-BaA, only the CYP1A2 gene was significantly induced, even at the lower dosage; CYP1A1 and 1B1 mRNA levels remained unchanged in Cl-BaA-treated rats compared with controls. To elucidate the role of such Cl-BaA exposure and induced CYPs at toxicity onset, we investigated the mutagenicity of BaA and Cl-BaA using Salmonella typhimurium TA98 and TA100. BaA and Cl-BaA at 10 µg/plate produced positive results in both strains in the presence of rat S-9. Incubation of Cl-BaA with recombinant rat CYP1A2 produced a significantly higher number of revertant colonies in TA98 and TA100 than in controls, but no such change was observed for BaA. In conclusion, BaA changes its own physiological and toxicological actions by its chlorination; (1) daily exposure to Cl-BaA selectively induces hepatic CYP1A2 in rats and (2) Cl-BaA induces frameshift mutations in the presence of CYP1A2, although BaA does not exert mutagenicity. This indicates that CYP1A2 may metabolize Cl-BaA to active forms.


Assuntos
Benzo(a)Antracenos/toxicidade , Fígado/efeitos dos fármacos , Mutagênicos/toxicidade , Salmonella typhimurium/efeitos dos fármacos , Animais , Hidrocarboneto de Aril Hidroxilases/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Citocromo P-450 CYP1A2 , Citocromo P-450 CYP1B1 , Citocromos/metabolismo , Mutação da Fase de Leitura , Regulação da Expressão Gênica/efeitos dos fármacos , Halogenação , Fígado/metabolismo , Masculino , Testes de Mutagenicidade , Ratos , Ratos Endogâmicos F344 , Salmonella typhimurium/metabolismo
6.
J Cell Biol ; 113(3): 615-22, 1991 May.
Artigo em Inglês | MEDLINE | ID: mdl-1673127

RESUMO

A novel Chlamydomonas flagellar mutant (oda-11) missing the alpha heavy chain of outer arm dynein but retaining the beta and gamma heavy chains was isolated. Restriction fragment length polymorphism analysis with an alpha heavy chain locus genomic probe indicated that the oda-11 mutation was genetically linked with the structural gene of the alpha heavy chain. In cross-section electron micrographs, the oda-11 axoneme lacked the outermost appendage of the outer arm, indicating that the alpha heavy chain should be located in this region in the wild-type outer arm. This mutant swam at 119 microns/s at 25 degrees C, i.e., at an intermediate speed between those of wild type (194 microns/s) and of oda-1 (62 microns/s), a mutant missing the entire outer dynein arm. The flagellar beat frequency (approximately 50 Hz) was also between those of wild type (approximately 60 Hz) and oda-1 (approximately 26 Hz). These results indicate that the outer dynein arm of Chlamydomonas can be assembled without the alpha heavy chain, and that the outer arm missing the alpha heavy chain retains partial function.


Assuntos
Chlamydomonas/genética , Dineínas/genética , Flagelos/química , Movimento Celular , Centrifugação com Gradiente de Concentração , Chlamydomonas/fisiologia , Chlamydomonas/ultraestrutura , Dineínas/química , Dineínas/fisiologia , Dineínas/ultraestrutura , Flagelos/fisiologia , Genes , Luz , Microscopia Eletrônica , Mutação , Polimorfismo de Fragmento de Restrição
7.
J Cell Biol ; 122(3): 653-61, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8335691

RESUMO

A new allele of the Chlamydomonas oda4 flagellar mutant (oda4-s7) possessing abnormal outer dynein arms was isolated. Unlike the previously described oda4 axoneme lacking all three (alpha, beta, and gamma) outer-arm dynein heavy chains, the oda4-s7 axoneme contains the alpha and gamma heavy chains and a novel peptide with a molecular mass of approximately 160 kD. The peptide reacts with a mAb (18 beta B) that recognizes an epitope on the NH2-terminal part of the beta heavy chain. These observations indicate that this mutant has a truncated beta heavy chain, and that the NH2-terminal part of the beta heavy chain is important for the stable assembly of the outer arms. In averaged electron microscopic images of outer arms from cross sections of axonemes, the mutant outer arm lacks its mid-portion, producing a forked appearance. Together with our previous finding that the mutant oda11 lacks the alpha heavy chain and the outermost portion of the arm (Sakakibara, H., D. R. Mitchell, and R. Kamiya. 1991. J. Cell Biol. 113:615-622), this result defines the approximate locations of the three outer arm heavy chains in the axonemal cross section. The swimming velocity of oda4-s7 is 65 +/- 8 microns/s, close to that of oda4 which lacks the entire outer arm (62 +/- 8 microns/s) but significantly lower than the velocities of wild type (194 +/- 23 microns/s) and oda11 (119 +/- 17 microns/s). Thus, the lack of the beta heavy chain impairs outer-arm function more seriously than does the lack of the alpha heavy chain, suggesting that the alpha and beta chains play different roles in outer arm function.


Assuntos
Chlamydomonas reinhardtii/fisiologia , Dineínas/fisiologia , Alelos , Animais , Western Blotting , Centrifugação com Gradiente de Concentração , Chlamydomonas reinhardtii/enzimologia , Chlamydomonas reinhardtii/genética , Dineínas/química , Dineínas/genética , Dineínas/ultraestrutura , Flagelos/fisiologia , Genes de Protozoários , Microscopia Eletrônica , Mutação , Supressão Genética
8.
Biochim Biophys Acta ; 1492(1): 216-20, 2000 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-11004492

RESUMO

Maize genomic clones encoding cytokinin-inducible response regulators, ZmRR1 and ZmRR2, have been isolated. In comparison with the corresponding cDNAs, ZmRR2 was found to be interrupted in the translated region by an intron whereas ZmRR1 was not. The 5'-flanking regions of the two genes shared conserved regions and putative cis-elements, which had been identified in maize or other plant species. The run-on transcription assay and the analysis of stable maize transformants of ZmRR1 promoter-beta-glucuronidase fusion gene revealed that the accumulation of the transcripts in response to cytokinins is, at least in parts, attributed by transcriptional activation.


Assuntos
Genoma de Planta , Proteínas de Plantas/genética , Regiões Promotoras Genéticas/genética , Ativação Transcricional , Zea mays/genética , Citocininas/fisiologia , Dados de Sequência Molecular , Plantas Geneticamente Modificadas , Mapeamento por Restrição , Análise de Sequência de DNA
9.
J Am Coll Cardiol ; 6(4): 744-9, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4031288

RESUMO

In some patients with mitral stenosis, a smoke-like echo is observed in the left atrial cavity. The present study in 116 consecutive patients with rheumatic mitral valve disease investigated the echocardiographic features and clinical significance of this echo. The smoke-like echo is characterized by the following echocardiographic features: 1) it is composed of numerous microechoes; 2) it curls up slowly in the enlarged left atrial cavity; and 3) it vanishes as soon as it pours into the ventricular cavity. Hemostasis in the left atrial cavity was considered to be an important underlying condition for development of the echo. Hemorheologic conditions indicated that the shear rate of blood flow in the left atrial cavity was calculated to be low enough for the development of red blood cell aggregation. These conditions suggest that the source of the smoke-like echo might be aggregated cells due to hemostasis in the left atrial cavity. Left atrial thrombi were detected in many patients who had this echo in the left atrial cavity. Although it has not been conclusively determined that the presence of the smoke-like echo is a necessary condition for thrombus formation, this echo appears to be closely related to thrombus formation in the left atrial cavity. It is concluded that the presence of this echo indicates severe left atrial hemostasis and is a warning for thrombus formation.


Assuntos
Ecocardiografia , Átrios do Coração , Doenças das Valvas Cardíacas/diagnóstico , Valva Mitral , Adulto , Idoso , Procedimentos Cirúrgicos Cardíacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico
10.
J Am Coll Cardiol ; 7(2): 425-31, 1986 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3511123

RESUMO

The pattern of normal blood flow in the right atrial cavity was studied using the newly developed real-time two-dimensional Doppler flow imaging technique as a standard reference for the Doppler diagnosis of heart diseases with intracardiac shunts at the atrial level. The study was performed primarily with use of the apical four chamber and the parasternal right ventricular inflow tract views in 21 healthy subjects. The following patterns were observed: blood from the inferior vena cava flowed up along the posterior wall of the right atrium and joined with blood from the superior vena cava in the posterocranial part of the right atrial cavity; the flow then coursed along the roof of the right atrium toward the tricuspid valve in the atrial relaxation phase. This flow was always noted along the interatrial septum in the four chamber view. During and after mid-systole of the right ventricle, additional blood flow away from the tricuspid valve appeared, moving from the valve to the central part of the right atrial cavity, that is, at the lower right of the preceding inflow; this flow was interpreted as arising from eddy currents caused by the preceding inflow. In early diastole of the right ventricle, the flow signal area along the interatrial septum and the roof of the right atrium extended into the right ventricular cavity through the tricuspid valve. In the atrial contraction phase only the blood near the tricuspid valve in the right atrial cavity appeared to flow into the right ventricular cavity. Inflow from the coronary sinus was almost undetectable.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Função Atrial , Ultrassonografia/métodos , Adolescente , Adulto , Criança , Pré-Escolar , Diástole , Humanos , Fluxo Sanguíneo Regional , Respiração , Sístole
11.
J Am Coll Cardiol ; 8(5): 1235-9, 1986 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-3760394

RESUMO

It has been difficult to diagnose mitral regurgitation due to valve perforation using either noninvasive or invasive methods, differentiating it from that resulting from incomplete coaptation of the mitral valve. This report describes three patients with infective endocarditis and mitral valve perforation, which was definitively diagnosed by the real-time two-dimensional Doppler flow imaging technique. In these three patients, B-mode echocardiography demonstrated an echo interruption on the anterior mitral leaflet. However, it was not certain whether this interruption was simply an echo dropout or indicated an interruption of the valve tissue. Doppler flow imaging then demonstrated unusual flow in the vicinity of the echo interruption, which appeared to flow from the left ventricular cavity into the left atrial cavity across the midportion of the anterior mitral valve leaflet during systole and in the opposite direction during diastole. This was interpreted as mitral valve perforation. In general, Doppler flow imaging may play a complementary role with B-mode echocardiography in cardiac diagnosis.


Assuntos
Ecocardiografia/métodos , Ruptura Cardíaca/diagnóstico , Valva Mitral , Adulto , Endocardite/complicações , Aneurisma Cardíaco/diagnóstico , Aneurisma Cardíaco/etiologia , Ruptura Cardíaca/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/etiologia
12.
J Am Coll Cardiol ; 5(1): 182-7, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3964804

RESUMO

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.


Assuntos
Ecocardiografia , Ruptura Cardíaca/diagnóstico , Septos Cardíacos/fisiopatologia , Infarto do Miocárdio/complicações , Idoso , Feminino , Átrios do Coração/fisiopatologia , Ruptura Cardíaca/etiologia , Ruptura Cardíaca/fisiopatologia , Comunicação Interventricular/patologia , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Artéria Pulmonar/fisiopatologia , Radiografia
13.
J Am Coll Cardiol ; 7(1): 82-8, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3941221

RESUMO

An attempt was made to determine whether mitral regurgitation could be detected and its severity evaluated semiquantitatively by newly developed real-time two-dimensional Doppler flow imaging in 109 patients who underwent left ventriculography. In the Doppler flow imaging technique, Doppler signals due to blood flow in the cardiac chambers are processed using a high speed autocorrelation technique, so that the direction, velocity and turbulence of the intracardiac blood flow are displayed in the color-coded mode on the monochrome B-mode echocardiogram in real time. Mitral regurgitant flow was imaged as a jet spurting out from the mitral valve orifice into the left atrial cavity. It was noted that the regurgitant jet in the left atrial cavity had a variety of orientations and dynamic features when studied by the present technique. The sensitivity of the technique in the detection of mitral regurgitation was 86% as compared with that of left ventriculography. Mitral regurgitation in the false negative cases was mostly mild. On the basis of the farthest distance reached by the regurgitant flow signal from the mitral valve orifice, the severity of regurgitation was graded on a four point scale and these results were compared with those of angiography. A significant correlation (r = 0.87) was found between Doppler imaging and angiography in the evaluation of the severity of mitral regurgitation. A similar result was obtained for the evaluation based on the area covered by the regurgitant signals in the left atrial cavity. Thus, noninvasive semiquantitative evaluation by real-time two-dimensional Doppler flow imaging appears to be a promising clinical technique.


Assuntos
Ecocardiografia/métodos , Insuficiência da Valva Mitral/classificação , Adolescente , Adulto , Idoso , Cateterismo Cardíaco , Ecocardiografia/instrumentação , Eletrocardiografia , Humanos , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/fisiopatologia , Radiografia , Sístole
14.
J Clin Endocrinol Metab ; 79(1): 223-6, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8027231

RESUMO

Although there are some reports, including our previous study, indicating the existence and biological action of epidermal growth factor (EGF) in human decidua, the site of its synthesis remains unknown. To clarify the EGF production during decidualization at a molecular level, gene expression of EGF in human endometrium/decidua was examined by Northern blot analysis and in situ hybridization. Northern blot hybridization using 32P-labeled human prepro-EGF complementary DNA was carried out for nonpregnant human endometria from hysterectomized uteri of leiomyoma, decidua from early pregnancy, and in vitro decidualized endometrial cells by medroxyprogesterone acetate (MPA). Although no hybridized band was found in the proliferative and secretory phase endometria, a specific band of 5 kilobases, in agreement with the size of human prepro-EGF messenger ribonucleic acid, was detected in decidua of early pregnancy as well as in in vitro MPA-induced decidual cells. In situ hybridization revealed that prepro-EGF messenger ribonucleic acid was observed in the stromal cells of decidua. These results demonstrate that the EGF gene is expressed in the process of decidualization, suggesting that EGF may play an important role in the decidualization process of human endometrium.


Assuntos
Decídua/fisiologia , Endométrio/metabolismo , Fator de Crescimento Epidérmico/genética , Expressão Gênica , Northern Blotting , Sondas de DNA , Endométrio/efeitos dos fármacos , Feminino , Humanos , Hibridização In Situ , Leiomioma/metabolismo , Acetato de Medroxiprogesterona/farmacologia , Gravidez , Precursores de Proteínas/genética , RNA Mensageiro/análise , RNA Mensageiro/metabolismo , Neoplasias Uterinas/metabolismo
15.
FEBS Lett ; 429(3): 259-62, 1998 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-9662428

RESUMO

We examined cytokinin and nitrate responsiveness in gene expression of five distinct response regulator homologs (ARR3-ARR7) in the leaves of nitrogen-starved Arabidopsis plants. The transcripts accumulated after spraying the shoots with t-zeatin. The induction of accumulation was highly specific for cytokinins. The transcripts also accumulated by supply of nitrate to the culture medium. These findings suggest that ARRs are involved in inorganic nitrogen signal transduction mediated by cytokinin as in the case of ZmCip1, a response regulator homolog recently identified in maize.


Assuntos
Arabidopsis/efeitos dos fármacos , Citocininas/farmacologia , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nitratos/farmacologia , Reguladores de Crescimento de Plantas/farmacologia , Proteínas de Plantas/biossíntese , Folhas de Planta/efeitos dos fármacos , RNA Mensageiro/biossíntese , RNA de Plantas/biossíntese
16.
Neurology ; 27(8): 741-5, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-196235

RESUMO

Despite focal degeneration and simplification of the postsynaptic region in Duchenne dystrophy, the postsynaptic acetylcholine receptor (AChR) is preserved. This is in contrast to myasthenia gravis where similar postsynaptic alterations are invariably associated with a marked decrease in AChR. There is no extrajunctional spread of AChR in Duchenne dystrophy. The amplitude and frequency of miniature end-plate potentials and the number of transmitter quanta released by nerve impulse are normal but the resting membrane potential is lower than normal. The findings indicate that the release and the postsynaptic responsiveness to acetylcholine are intact in Duchenne dystrophy.


Assuntos
Acetilcolina/farmacologia , Placa Motora/fisiologia , Distrofias Musculares/patologia , Junção Neuromuscular/fisiologia , Receptores Colinérgicos , Criança , Pré-Escolar , Humanos , Potenciais da Membrana , Distrofias Musculares/fisiopatologia , Transmissão Sináptica
17.
Neurology ; 29(2): 179-88, 1979 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-571062

RESUMO

Experimental autoimmune myasthenia gravis (EAMG) was passively transferred with immunoglobulin from rats with chronic EAMG to normal recipients. IgG and C3 were localized on terminal expansions of junctional folds of end-plates by 6 hours. Segments of folds rich in acetylcholine receptor (AChR) and coated with IgG and C3 were shed into the synaptic space by 24 hours, resulting in AChR deficiency of the postsynaptic membrane. Many sensitized postsynaptic regions were destroyed by macrophages by day 2, but effective nerve-muscle contacts were reestablished by day 5. On day 10, end-plates were still structurally abnormal and showed AChR deficiency, but the animals were clinically recovered. On day 54, postsynaptic regions were still reduced in size, with slight reduction of postsynaptic AChR. Throughout the study, the miniature end-plate potential amplitude tended to vary directly with morphometric estimates of the abundance of the postsynaptic membrane reacting for AChR. Complement-mediated injury to the junctional folds and opsonization of the postsynaptic region can explain the morphologic changes. It is not yet known why phagocytic invasion of the end-plate occurs in acute EAMG and in passively transferred EAMG induced by chronic EAMG immuglobulin, but not in chronic EAMG and only rarely in the human disease.


Assuntos
Complexo Antígeno-Anticorpo , Doenças Autoimunes/imunologia , Imunização Passiva , Placa Motora/ultraestrutura , Miastenia Gravis/imunologia , Junção Neuromuscular/ultraestrutura , Receptores Colinérgicos/imunologia , Animais , Complemento C3/análise , Complemento C3/imunologia , Imunoglobulina G/análise , Placa Motora/imunologia , Ratos
18.
J Med Chem ; 20(5): 732-6, 1977 May.
Artigo em Inglês | MEDLINE | ID: mdl-404425

RESUMO

The synthesis, antimicrobial activity, and binding to ribosomes of leucomycin and leucomycin derivatives are described. In general, the binding of the leucomycins and the leucomycin derivatives to ribosomes correlated with their antimicrobial activity. Some 2'-O-acyl derivatives apparently underwent gradual hydrolysis during antimicrobial assays, for their binding to ribosomes was poor compared to their relatively good antimicrobial activies. Correlation between antimicrobial activity and binding to ribosomes, their molecular site of action, provides some insight into the nature of the active molecular moieties.


Assuntos
Antibacterianos/síntese química , Escherichia coli/metabolismo , Leucomicinas/síntese química , Ribossomos/metabolismo , Bacillus subtilis/efeitos dos fármacos , Depressão Química , Eritromicina/metabolismo , Escherichia coli/ultraestrutura , Klebsiella pneumoniae/efeitos dos fármacos , Leucomicinas/metabolismo , Leucomicinas/farmacologia , Testes de Sensibilidade Microbiana , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
19.
Am J Cardiol ; 49(2): 467-72, 1982 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-6460434

RESUMO

In 35 of 70 patients with rheumatic mitral valve disease, two dimensional echocardiography revealed the posterobasal wall of the left ventricle to be entrapped between the left ventricular and atrial cavities and bent inward. The motion of the bending segment was paradoxical. This abnormality was assumed to be induced by the left atrial dilatation extending inferiorly behind the left ventricle, because the length of the bending segment correlation with the left atrial dimension. There was no correlation between the degree of abnormal bending and left atrial pressure, mitral valve pressure gradient or left ventricular dimension. The systolic excursion of the posterobasal wall of the left ventricle was reduced according to the length of the bending segment. This abnormal feature was also observed in five postmortem heart specimens with an extremely dilated left atrium. The macroscopic and microscopic findings in the myocardium of the bending segment were not different from those of the remaining segment of the left ventricle. Therefore, the asynergic motion of the bending segment is assumed to be caused by the abnormal spatial orientation of the left ventricle and the left atrium. It should be considered that the giant left atrium not only oppresses the surrounding organs but also affects the left ventricle.


Assuntos
Cardiomegalia/fisiopatologia , Ecocardiografia , Ventrículos do Coração/fisiopatologia , Cardiopatia Reumática/fisiopatologia , Adulto , Diástole , Feminino , Átrios do Coração/patologia , Átrios do Coração/fisiopatologia , Ventrículos do Coração/patologia , Hemodinâmica , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/patologia , Insuficiência da Valva Mitral/fisiopatologia , Estenose da Valva Mitral/patologia , Estenose da Valva Mitral/fisiopatologia , Sístole
20.
Am J Cardiol ; 54(7): 857-68, 1984 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-6486038

RESUMO

The clinical significance of a newly developed real-time 2-dimensional (2-D) Doppler flow imaging technique was assessed. In the instrumentation of the echocardiograph, the pulsed Doppler mechanism was incorporated in a wide-angle, phased-array system. The Doppler flow signals obtained from the cardiac chamber were processed on the basis of the autocorrelation principle. The direction, velocity and variance of the intracardiac blood flow were calculated in real time and displayed in the color-coded mode on the television screen, and were superimposed on the 2-D echocardiographic image of the heart. The technique was used in 20 healthy subjects and 100 cardiac patients. The new technique clearly visualized the whole aspect of intracardiac blood flow by the cine mode in real time; thus, the technique may be called Doppler cineangiocardiography. The mitral inflow and the aortic ejection flow were clearly demonstrated. A regurgitant jet from the valve orifices was dynamically visualized as seen in the cineangiogram. The spatial orientation and extent of the regurgitant jet were easily assessed. The jet stream through the stenotic mitral orifice was well imaged in the left ventricular cavity, showing a variety of stream directions. Intracardiac shunts in ventricular septal defect and atrial septal defect were clearly visualized. The defect could be localized on the interventricular septum on the basis of the site where the shunt flow spurted, although the echocardiographic interruption was not demonstrated in the 2-D echocardiographic image of the cardiac structure. Although some technical problems remain, our new technique greatly improves the diagnostic efficacy of ultrasound.


Assuntos
Circulação Coronária , Ecocardiografia/métodos , Cardiopatias/fisiopatologia , Adolescente , Adulto , Idoso , Insuficiência da Valva Aórtica/fisiopatologia , Criança , Cineangiografia/métodos , Feminino , Cardiopatias Congênitas/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência da Valva Mitral/fisiopatologia , Estenose da Valva Mitral/fisiopatologia , Insuficiência da Valva Pulmonar/fisiopatologia , Insuficiência da Valva Tricúspide/fisiopatologia
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