RESUMO
BACKGROUND AND PURPOSE: The association between an increased supraventricular ectopic beat (SVEB) and subclinical cerebrovascular disease remains unclear. Given the emerging concept that an increased SVEB is a marker of atrial cardiomyopathy or atherosclerosis burden, we sought to determine whether excessive supraventricular ectopic activity (ESVEA) is associated with a higher burden of subclinical cerebrovascular disease in the middle-aged to older cohort with neither apparent stroke nor atrial fibrillation. METHODS: We conducted a cross-sectional population-based study of 462 men (mean age, 68.1 years) who underwent 24-h Holter electrocardiography and brain magnetic resonance imaging. ESVEA was defined as the presence of >10 SVEBs/h. Subclinical cerebrovascular diseases were defined as silent brain infarct (SBI), white matter hyperintensity (WMH) and intracranial atherosclerotic stenosis (ICAS). The association of ESVEA with the presence of subclinical cerebrovascular diseases was adjusted for potential confounding covariates. RESULTS: A total of 88 (19.0%) participants had ESVEA and 81 (17.5%), 91 (19.7%) and 109 (23.6%) had SBI, WMH and ICAS, respectively. In multivariable-adjusted Poisson regression with robust error variance, ESVEA was associated with the presence of WMH (relative risk, 1.58; 95% confidence interval, 1.06-2.36) and ICAS (relative risk, 1.49; 95% confidence interval, 1.02-2.18), but not with that of SBI (relative risk, 1.32; 95% confidence interval, 0.86-2.01). These associations were consistent when the graded distributions of subclinical cerebrovascular diseases were applied as outcomes in ordinal logistic regression. CONCLUSIONS: The ESVEA was independently associated with higher burdens of WMH and ICAS. This suggests that increased SVEBs might improve risk stratification of individuals at high risk of subclinical cerebrovascular disease and consequently apparent ischaemic stroke.
Assuntos
Infarto Encefálico/epidemiologia , Cardiomiopatias/epidemiologia , Arteriosclerose Intracraniana/epidemiologia , Leucoaraiose/epidemiologia , Idoso , Infarto Encefálico/diagnóstico por imagem , Cardiomiopatias/diagnóstico , Comorbidade , Estudos Transversais , Eletrocardiografia Ambulatorial , Humanos , Arteriosclerose Intracraniana/diagnóstico por imagem , Leucoaraiose/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/fisiopatologiaRESUMO
BACKGROUND: Intractable hiccup and nausea (IHN) are unique symptoms in neuromyelitis optica (NMO). Recent studies have strongly suggested that the pathogenesis of NMO is closely associated with anti-aquaporin-4 (AQP4) antibody. However, clinical implications of IHN and the relationship with anti-AQP4 antibody remain unknown. METHODS: The past medical records of 35 patients with seropositivity for anti-AQP4 antibody were reviewed. We also followed the titres of anti-AQP4 antibody in a patient with NMO, who had newly developed IHN. RESULTS: Of the 35 patients, 15 patients (43%) had episodes of IHN. There was a total of 35 episodes of IHN in these 15 patients and, of the 35 episodes, hiccup was seen in 23 episodes (66%) and nausea was seen in 28 episodes (80%). The IHN frequently preceded (54%) or accompanied (29%) myelitis or optic neuritis. The IHN was often preceded by an episode of viral infection. The titres of anti-AQP4 antibody were remarkably increased when the intractable hiccup appeared in a case. CONCLUSIONS: IHN could be a clinical marker for the early phase of an exacerbation. Careful observation may be needed when INH is seen in patients with NMO, and the early initiation of the treatment could prevent subsequent neurological damage.
Assuntos
Anticorpos Anti-Idiotípicos/imunologia , Aquaporina 4/imunologia , Soluço/diagnóstico , Soluço/epidemiologia , Náusea/diagnóstico , Náusea/epidemiologia , Neuromielite Óptica , Doença Aguda , Adolescente , Adulto , Idoso , Diagnóstico Diferencial , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/epidemiologia , Neuromielite Óptica/imunologia , PrevalênciaRESUMO
OBJECTIVE: To delineate the MRI features that distinguish neuromyelitis optica (NMO) from multiple sclerosis (MS). METHODS: We compared the distribution of the spinal cord lesions by analyzing 1) lesion area, 2) lesion density (by superimposing the lesions onto the standard sections of the cervical and thoracic cord with appropriate transparencies using computer software), and 3) T1-hypointensity in axial sections of MRI in NMO and MS. RESULTS: In NMO, 60-70% of the cervical and thoracic cord MRI lesions occupied more than half of the cord area and mainly involved the central gray matter in the acute stage. In the chronic stage, half or more of the lesions were localized at the central gray matter region. The lesion superimposition analysis also revealed much higher densities in the central gray matter region than in the peripheral white matter regions. Two patients with NMO had T1-hypointense lesions in the central region. In contrast, over 80% of the lesions in MS were localized in the lateral and posterior white matter regions of the cord in the chronic as well as acute stage. Lesion densities were much higher in the lateral and posterior white matter regions than in the central gray matter region. None of the lesions in MS were T1-hypointense. CONCLUSIONS: These MRI findings strongly suggest a preferential involvement in the spinal central gray matter in NMO which is distinct from MS.
Assuntos
Neuromielite Óptica/patologia , Medula Espinal/patologia , Adulto , Idoso , Feminino , Humanos , Imunoglobulina G/metabolismo , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
This study investigates the relation between the serological status of NMO (neuromyelitis optica)-IgG and the clinical and MRI features in Japanese patients with multiple sclerosis. Serum NMO-IgG was tested in 35 Japanese patients diagnosed with multiple sclerosis, including 19 with the optic-spinal form of multiple sclerosis (OSMS), three with the spinal form of multiple sclerosis (SMS), and 13 with the conventional form of multiple sclerosis (CMS), which affects the brain. NMO-IgG was detected in 14 patients, 12 with OSMS and 2 with CMS. In these patients, longitudinally extensive (> 3 vertebral segments) spinal cord lesions (93% v 57%) and permanent, complete blindness (no perception of light) in at least one eye (50% v 0%) were the noticeable features as compared with NMO-IgG-negative OSMS. The two patients having CMS with NMO-IgG had unusual brain lesions, but in other respects had features suggesting OSMS. NMO-IgG was detected in more than half the number of patients with OSMS and in some patients with CMS. This newly discovered serum autoantibody was markedly associated with longitudinally extensive spinal cord lesions and with complete blindness, suggesting severe optic-spinal disease.
Assuntos
Imunoglobulina G/sangue , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Neuromielite Óptica/imunologia , Neuromielite Óptica/patologia , Adulto , Autoanticorpos , Cegueira/etiologia , Encéfalo/patologia , Feminino , Humanos , Japão , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Esclerose Múltipla/complicações , Neuromielite Óptica/sangue , Neuromielite Óptica/complicações , Medula Espinal/patologiaRESUMO
Lymphoma was seen in an 11-year-old female savanna monkey (Ceropithecus aethiops). The superficial inguinal and visceral lymph nodes were markedly enlarged, and their architecture was completely effaced by neoplastic cells. The neoplastic cells, which were highly pleomorphic, resembled those in adult T-cell lymphoma-leukemia in humans. Ultrastructurally the neoplastic cells were characterized by nuclear irregularity and clustered dense bodies, and almost all cells showed positivity for CD3. The animal had been reared with her family, and her mother and 2 brothers had antibodies reactive to human T-cell leukemia virus. This virus serologically cross-reacts with simian T-cell leukemia virus, which may be the causative agent of the present neoplasm.
Assuntos
Chlorocebus aethiops , Infecções por Deltaretrovirus/veterinária , Linfonodos/patologia , Linfoma de Células T/veterinária , Doenças dos Macacos/virologia , Vírus Linfotrópico T Tipo 1 de Símios , Animais , Infecções por Deltaretrovirus/patologia , Feminino , Linfoma de Células T/patologia , Linfoma de Células T/virologia , Doenças dos Macacos/patologia , Vírus Linfotrópico T Tipo 1 de Símios/imunologiaRESUMO
A 52 year-old male was admitted to our hospital with the complaint of the hypochondrial pain after meal in February 1989. He was diagnosed to be RAEB and to have common bile duct stone. His red blood cells (RBC) could not be agglutinated with anti-A, anti-B, or anti-A, B. The agglutinability of the cells to Ulex europaeus (anti-H) was the same to the normal type B RBC, and his serum contained anti-I, anti-E, and anti-c. In his saliva, both B and H antigens were detected. The glycosyl B transferase in his serum showed similar activity to that of normal individual with type B RBC. When his RBC were treated with normal type B transferase, the cells obtained the reactivity to anti-B but they agglutinated much weaker than the type O cells treated with the enzyme. These results indicated that the low agglutinability of his RBC could not be due to the low transferase activity but the qualitative or quantitative changes of the precursor molecules of the type B substance of the cells.
Assuntos
Sistema ABO de Grupos Sanguíneos/imunologia , Anemia Refratária com Excesso de Blastos/imunologia , Anemia Refratária/imunologia , Isoantígenos/análise , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
Hemolytic anemia and possible aplastic crisis with symptoms including jaundice, general fatigue and dark urine developed in a man being treated only by lansoprazole. Five days later, he was treated with antibiotics. The next day, he was admitted to our hospital because of jaundice. On admission, the hemoglobin was 14.0 g/dl, reticulocyte count 8/1000, platelets 79 x 10(9)/l and total bilirubin 12.4 mg/dl (indirect bilirubin 9.5 mg/dl). The above medications were discontinued. The direct Coombs antiglobulin test was positive. Examination of the complement revealed a C3 fiter at the upper limit of normal and an increased C4 and CH50. Three days after admission, he had a severe anemia. The hemoglobin was 3.3 g/DL. We thought it possible that aplastic crisis had followed the hemolytic anemia induced by lansoprazole. He was treated with blood transfusions and corticosteroids. He recovered from anemia within three weeks. Exhaustive studies to identify the cause of the hemolytic anemia were undertaken with negative results. We detected IgG antibody to lansoprazole. We believe that the hemolytic anemia was induced by lansoprazole.
Assuntos
Anemia Hemolítica/induzido quimicamente , Antiulcerosos/efeitos adversos , Omeprazol/análogos & derivados , 2-Piridinilmetilsulfinilbenzimidazóis , Anemia Hemolítica/imunologia , Humanos , Lansoprazol , Masculino , Pessoa de Meia-Idade , Omeprazol/efeitos adversos , Úlcera Gástrica/tratamento farmacológicoAssuntos
Esclerose Múltipla , Neuromielite Óptica , Nervo Óptico/patologia , Medula Espinal/patologia , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla/diagnóstico , Esclerose Múltipla/fisiopatologia , Neuromielite Óptica/diagnóstico , Neuromielite Óptica/fisiopatologia , PrognósticoRESUMO
BACKGROUND: The corpus callosum is commonly involved in multiple sclerosis (MS), but the characteristics of callosal lesions in neuromyelitis optica (NMO) are unknown.ObjectiveTo reveal the features of callosal lesions in NMO in comparison to MS. METHODS: We retrospectively reviewed the medical records and the brain magnetic resonance imaging films of 56 patients with MS and 22 patients with NMO. RESULTS: In MS, 36 (64.3%) of 56 patients had callosal lesions, but only four patients had acute lesions. All such acute lesions were small, isolated and non-edematous, and the intensity was homotonic. Chronic lesions were observed in 34 patients with MS, and 32 (94%) of them presented small lesions located at the callosal lower margin ("hemi-oval pattern"). Meanwhile, four (18.2%) patients with NMO had callosal lesions, and three of them had acute lesions. Those acute lesions were multiple, large edematous ones with heterogeneous intensity ("marbled pattern"). In the chronic stage, the lesions shrank or disappeared. CONCLUSIONS: Acute large, edematous callosal lesions occasionally occur in NMO. Similar to longitudinally extensive transverse myelitis, such callosal lesions may reflect severe edematous inflammation in NMO, and may provide additional evidence that the pathogenesis in NMO is different from that in MS.
Assuntos
Edema Encefálico/patologia , Corpo Caloso/patologia , Imageamento por Ressonância Magnética , Esclerose Múltipla/patologia , Neuromielite Óptica/patologia , Doença Aguda , Adulto , Edema Encefálico/imunologia , Feminino , Humanos , Imunoglobulina G/sangue , Pessoa de Meia-Idade , Esclerose Múltipla/imunologia , Neuromielite Óptica/imunologia , Estudos Retrospectivos , Índice de Gravidade de DoençaRESUMO
Of 23 neuromyelitis optica (NMO) cases, we found two cases with oligoclonal IgG bands (OBs). Both patients were positive for NMO-IgG. Their common features were long disease duration and co-existing autoimmune diseases (myasthenia gravis and sicca syndrome). Although OBs are mostly negative in NMO, which distinguishes it from multiple sclerosis (MS), they can be positive by long-standing autoimmunity, which may not be directly related to NMO.
Assuntos
Imunoglobulina G/análise , Imunoglobulina G/sangue , Neuromielite Óptica/imunologia , Idoso , Doenças Autoimunes/imunologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Medula Espinal/patologiaRESUMO
The neurofilament heavy chain (NfHSMI35), a biomarker of axonal damage in the CSF, was measured in patients with neuromyelitis optica (NMO) and multiple sclerosis (MS). Significantly high CSF NfHSMI35 levels (>0.73 ng/mL) were found in 6 of 24 (25%) of the patients with NMO but none of the patients with MS (0/24). This finding suggests that axonal damage is more severe in NMO than in MS.
Assuntos
Proteínas de Neurofilamentos/líquido cefalorraquidiano , Neuromielite Óptica/líquido cefalorraquidiano , Adulto , Idoso , Biomarcadores/líquido cefalorraquidiano , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neuromielite Óptica/diagnóstico , Estudos RetrospectivosRESUMO
Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system (CNS) with a poor prognosis in terms of the optic-spinal function. Recently, a serum autoantibody (NMO-IgG) binding to the blood-brain barrier region was detected exclusively in patients with NMO and its high risk group. We treated six NMO-IgG-positive patients (all female; age 21-67 years old, median 41; three with optic neuritis and three with myelitis) who were unresponsive to high-dose intravenous methylprednisolone (HIMP), with plasma exchange (PE) (three to five exchanges, 2-3 L each). Three of the patients (one with optic neuritis and two with myelitis) showed definite functional improvement following PE. The clinical improvement started to appear after one or two exchanges, while there was little or no improvement in the other three patients. Such quick clinical responses to PE suggest a pathogenetic role of humoral immune factors in NMO, although delayed responses to the corticosteroid therapy might have contributed to the therapeutic efficacy, in part. Further clinical and in vitro studies are needed to determine whether the removal of NMO-IgG is directly relevant to the therapeutic efficacy. PE may hasten the functional recovery from corticosteroid-resistant relapses in some NMO-IgG-positive patients with NMO.
Assuntos
Neuromielite Óptica/imunologia , Neuromielite Óptica/terapia , Troca Plasmática , Adulto , Anti-Inflamatórios/administração & dosagem , Autoanticorpos/sangue , Barreira Hematoencefálica/imunologia , Terapia Combinada , Resistência a Medicamentos , Feminino , Humanos , Imunoglobulina G/sangue , Injeções Intravenosas , Imageamento por Ressonância Magnética , Metilprednisolona/administração & dosagem , Pessoa de Meia-Idade , Neuromielite Óptica/patologia , Recidiva , Medula Espinal/patologiaRESUMO
Neuromyelitis optica (NMO) is a relapsing neurologic disease characterized by severe optic neuritis and transverse myelitis. A disease-modifying therapy for NMO has not been established. We retrospectively analysed the effect of low-dose corticosteroid (CS) monotherapy on the annual relapse rate in nine patients with NMO. We divided the clinical course in each patient into two periods; the CS Period in which CS was administered, and the No CS Period in which CS was not administered. Periods related to other immunological therapies, such as high-dose methylprednisolone, immunosuppressants, interferon-beta, and plasma exchange, were excluded. As a result, the annual relapse rate during the CS Periods [median, 0.49 (range, 0-1.31)] was found to be significantly lower than that during the No CS Periods [1.48 (0.65-5.54)]. As for the dose of CS, relapses occurred significantly more frequently with ;10 mg/day or less' than with ;over 10 mg/day' (odds ratio: 8.75). The results of the present study suggest a beneficial effect of low-dose CS monotherapy in reducing relapses in NMO.
Assuntos
Corticosteroides/uso terapêutico , Neuromielite Óptica/prevenção & controle , Adulto , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos RetrospectivosRESUMO
This study characterizes the inhibiting effect of diltiazem and nitroglycerin on periodic contractions of isolated human coronary arteries. Isometric force of coronary ring segments from sixty-nine cadavers was recorded in a muscle bath. To quantify the experimental results, we used 3 X 10(-6) M prostaglandin F2 alpha to induce the periodic contractions of a certain force. When diltiazem was added during the periodic contractions, the amplitude of oscillations gradually decreased until eventually oscillations ceased completely. The process prior to the cessation of the oscillations was characterized mainly by the inhibition of the contraction phase. The inhibition rate at the time of the complete cessation of oscillations was 49.3 +/- 6.3% at 5 X 10(-7) M. The time required for complete disappearance of oscillations was dependent on the diltiazem concentration. When nitroglycerin was added during periodic contractions, the oscillations did not disappear. Compared to the contraction phase, the relaxation phase was appreciably inhibited. With only 10(-7) M diltiazem, the rate of inhibition of the contraction phase was 22.0 +/- 7.7%, whereas the preliminary treatment with 5 X 10(-8) M nitroglycerin led to a complete cessation of the oscillations, and suppression of the level of the contractions to a significantly greater extent, viz. 58.7 +/- 5.8% (p less than 0.001). Therefore, it is considered more effective in the treatment and prevention of coronary spasm to use diltiazem and nitroglycerin simultaneously rather than individually.
Assuntos
Benzazepinas/farmacologia , Vasos Coronários/efeitos dos fármacos , Diltiazem/farmacologia , Nitroglicerina/farmacologia , Prostaglandinas F/farmacologia , Vasoconstrição/efeitos dos fármacos , Vasoespasmo Coronário/prevenção & controle , Dinoprosta , Relação Dose-Resposta a Droga , Humanos , Técnicas In Vitro , Músculo Liso Vascular/efeitos dos fármacos , PeriodicidadeRESUMO
Bundles of smooth muscles in the intimal layer of the human coronary artery contracted in a longitudinal direction on the application of vasoactive substances. The data indicate that the human coronary artery contracts not only transversely but also longitudinally.
Assuntos
Vasos Coronários/fisiologia , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/fisiologia , Acetilcolina/farmacologia , Idoso , Cafeína/farmacologia , Vasos Coronários/efeitos dos fármacos , Vasos Coronários/ultraestrutura , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/ultraestrutura , Potássio/farmacologiaRESUMO
The aim of this study was to evaluate the contractions of postmortem human saphenous veins under pulsatile flow conditions as a simulation of coronary-aortic bypass graft (CABG) surgery. Twenty-five cylindrical specimens of veins, obtained from 20 cadavers several hours after death, were mounted in a pulsatile flow system with a pulse rate of 80/min and a mean flow rate of 7 ml/min at various perfusion pressures. Prostaglandin F2 alpha(PGF2 alpha) was then applied to the outer physiological salt solution at a concentration of 3 X 10(-6) mol. Of the 25 veins, 18 (72%) contracted and seven did not. Contractions were observed at a mean perfusion pressure of less than 60 mmHg but not at higher pressures. Three contraction patterns were observed: One caused pressure gradients between the proximal and distal sites of the vein and showed periodic contractions (P); one showed only tonic contractions (T); the other showed pulse pressure increase without developing the pressure gradients (PP). The incidences of P, T, and PP in the 18 instances of contraction were 50%, 33%, and 17%, respectively. Repeated applications of PGF2 alpha to the same vein with the same and/or increased perfusion pressure caused changes of pattern in the direction of P to T, to PP, and to no response, whereas decreasing perfusion pressure caused the patterns to change in the reverse direction. The pressure gradients that developed in veins showing P and T patterns correlated well with the mean perfusion pressure (r = 0.68, P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Assuntos
Contração Muscular , Fluxo Pulsátil , Reologia , Veia Safena/fisiologia , Idoso , Velocidade do Fluxo Sanguíneo , Pressão Sanguínea , Ponte de Artéria Coronária , Dinoprosta , Feminino , Humanos , Técnicas In Vitro , Masculino , Pessoa de Meia-Idade , Contração Muscular/efeitos dos fármacos , Perfusão , Mudanças Depois da Morte , Prostaglandinas F/farmacologiaRESUMO
Peripheral vascular disease is often complicated with ischemic heart disease and is associated with increased cardiac mortality. Latent progression of sclerotic changes in the arteries supplying the lower extremities is often present but undiagnosed. We examined the influence of sclerotic changes of the iliac arteries on the late outcome in 79 patients with ischemic heart disease. Lower abdominal aortography was performed at the time of cardiac catheterization between December 1989 and January 1991. The degree of sclerotic change in the iliac arteries was assessed according to aortography findings such as stenosis, dilatation or bend, with higher scores representing more advanced sclerosis (aortography score). The mean aortography score of all patients was 5.8 +/- 4.6. The patients were followed up for 4.4 +/- 1.2 years to monitor the occurrence of cardiac events (cardiac death, acute myocardial infarction, coronary bypass surgery, or coronary angioplasty for new lesion). The cardiac event-free rate at 5 years was 76.6% in the high score group (32 patients with scores of 6 or more) and 92.9% in the low score group (47 patients with scores of 5 or less). The difference was significant (p = 0.007) by log-rank test. The hazard rate of the aortography score for predicting risk of cardiac event was 1.11 by the Cox proportional hazards model (95% confidence intervals: 1.01-1.23, p = 0.039). When the analysis was adjusted for coronary bypass surgery as primary therapy, the number of diseased coronary arteries, or the presence of peripheral vascular disease, similar results were obtained. In conclusion, more severe sclerotic change in iliac arteries is associated with a higher incidence of cardiac events in patients with ischemic heart disease.
Assuntos
Arteriosclerose/patologia , Artéria Ilíaca/patologia , Isquemia Miocárdica/patologia , Idoso , Aortografia , Arteriosclerose/complicações , Arteriosclerose/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Artéria Ilíaca/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , PrognósticoRESUMO
The presumptive muscle cells (B5.1 blastomeres) were isolated from 16-cell-stage embryos of the ascidian, Ciona intestinalis. The isolated cells were allowed to divide either twice or three times thereafter. Then further divisions of the cells were continuously inhibited by a simultaneous treatment with aphidicolin (a specific inhibitor of DNA synthesis) and cytochalasin B (an inhibitor of cytokinesis). When development of muscle-specific acetylcholinesterase in these division-arrested progeny cells of B5.1 blastomeres was examined histochemically, the B5.1 blastomeres which had been allowed two further divisions did not produce any detectable acetylcholinesterase activity. Whereas those which had been allowed three further divisions showed the tissue-specific enzyme activity. These results provide further evidence for the presence of a quantal DNA replication cycle for the tissue-specific enzyme development, which is qualitatively different from the other DNA replication cycles.
Assuntos
Acetilcolinesterase/biossíntese , Blastômeros/enzimologia , Replicação do DNA/efeitos dos fármacos , Músculos/embriologia , Animais , Afidicolina , Blastômeros/citologia , Diferenciação Celular/efeitos dos fármacos , Ciona intestinalis/embriologia , Citocalasina B/farmacologia , DNA/biossíntese , DNA Polimerase II/antagonistas & inibidores , Diterpenos/farmacologia , Músculos/enzimologiaRESUMO
To obtain specific immunological probes for studying molecular mechanisms involved in the early embryonic development of ascidians, we have produced monoclonal antibodies directed against a homogenate of larvae of the ascidian Halocynthia roretzi. Among these, we have screened monoclonal antibodies that specifically recognize cells and/or tissues of the embryo. Characterization of six epidermis-specific monoclonal antibodies (including larval tunic-specific and larval fin-specific), three muscle-specific antibodies, two endoderm-specific antibodies, one notochord-specific antibody and two monoclonal antibodies that specifically recognize trunk-lateral cells suggests that these monoclonal antibodies may be useful as markers for analysing molecular mechanisms involved in specification of these cells. Seven monoclonal antibodies characteristically stain intercellular materials of the developing embryo and may therefore be valid for studying cellular construction of the embryo. Furthermore, monoclonal antibodies that recognize components of follicle cells, perivitelline space and sperm have also been established.
Assuntos
Anticorpos Monoclonais , Óvulo/imunologia , Urocordados/embriologia , Animais , Antígenos/análise , Endoderma/imunologia , Epiderme , Masculino , Músculos/imunologia , Notocorda/imunologia , Espermatozoides/imunologia , Distribuição Tecidual , Urocordados/imunologiaRESUMO
The myoplasm of Ciona intestinalis eggs, believed to contain cytoplasmic determinants responsible for muscle cell differentiation in ascidian embryos, emits weak pale-blue autonomous fluorescence. Utilizing this feature as a marker, the cytoplasm was isolated according to the method described by Jeffery (1985b). Electron microscopy showed that the isolated cytoplasm contained mitochondria, pigment granules, yolk particles and fine granular materials; these are ultrastructural components of the myoplasm of the intact egg. Monoclonal antibodies were prepared against the isolated cytoplasm. Twelve monoclonal antibodies, identified by indirect immunofluorescence, stained the myoplasmic region. When unfertilized eggs were centrifuged, stratifying their mitochondria and some other cytoplasmic components, components identified by several antibodies, for example IIG6B2, remained at the peripheral cytoplasm of the egg. Other antibodies recognized components stratified as the mitochondrial layer. Four representative antibodies were microinjected into fertilized eggs in order to examine their inhibitory effects on the muscle differentiation; the IIG6B2 antibody blocked the development of muscle-specific acetylcholinesterase in more than 80% of the embryos tested.