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1.
Psychother Psychosom ; 80(6): 345-52, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21829046

RESUMO

BACKGROUND: The aim of the present randomized controlled trial was to compare the outcome of 2 active treatments for posttraumatic stress disorder (PTSD) as a consequence of war and torture: narrative exposure therapy (NET) and stress inoculation training (SIT). METHODS: Twenty-eight PTSD patients who had experienced war and torture, most of them asylum seekers, received 10 treatment sessions of either NET or SIT at the Outpatient Clinic for Refugees, University of Konstanz, Germany. Posttests were carried out 4 weeks after treatment, and follow-up tests were performed 6 months and 1 year after treatment. The main outcome measure was the PTSD severity score according to the Clinician-Administered PTSD Scale (CAPS) at each time point. RESULTS: A significant reduction in PTSD severity was found for NET, but not for SIT. A symptom reduction in the NET group occurred between pretest and the 6-month follow-up examination, the effect size being d = 1.42 (for SIT: d = 0.12), and between pretest and the 1-year follow-up, the effect size being d = 1.59 (for SIT: d = 0.19). The rates and scores of major depression and other comorbid disorders did not decrease significantly over time in either of the 2 treatment groups. CONCLUSIONS: The results indicate that exposure treatments like NET lead to a significant PTSD symptom reduction even in severely traumatized refugees and asylum seekers.


Assuntos
Terapia Implosiva/métodos , Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Tortura , Guerra , Comorbidade , Seguimentos , Alemanha , Humanos , Transtornos do Humor/diagnóstico , Transtornos do Humor/epidemiologia , Narração , Escalas de Graduação Psiquiátrica , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/diagnóstico , Transtornos de Estresse Pós-Traumáticos/epidemiologia , Tortura/psicologia , Resultado do Tratamento
2.
J Cell Biol ; 100(1): 161-74, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3965469

RESUMO

During several months of denervation, rat mixed muscles lose slow myosin, though with variability among animals. Immunocytochemical studies showed that all the denervated fibers of the hemidiaphragm reacted with anti-fast myosin, while many reacted with anti-slow myosin as well. This has left open the question as to whether multiple forms of myosin co-exist within individual fibers or a unique, possibly embryonic, myosin is present, which shares epitopes with fast and slow myosins. Furthermore, one can ask if the reappearance of embryonic myosin in chronically denervated muscle is related both to its re-expression in the pre-existing fibers and to cell regeneration. To answer these questions we studied the myosin heavy chains from individual fibers of the denervated hemidiaphragm by SDS PAGE and morphologically searched for regenerative events in the long term denervated muscle. 3 mo after denervation the severely atrophic fibers of the hemidiaphragm showed either fast or a mixture of fast and slow myosin heavy chains. Structural analysis of proteins sequentially extracted from muscle cryostat sections showed that slow myosin was still present 16 mo after denervation, in spite of the loss of the selective distribution of fast and slow features. Therefore muscle fibers can express adult fast myosin not only when denervated during their differentiation but also after the slow program has been expressed for a long time. Light and electron microscopy showed that the long-term denervated muscle maintained a steady-state atrophy for the rat's life span. Some of the morphological features indicate that aneural regeneration events continuously occur and significantly contribute to the increasing uniformity of the myosin gene expression in long-term denervated diaphragm.


Assuntos
Denervação Muscular , Músculo Liso/fisiologia , Miosinas/análise , Animais , Células Cultivadas , Diafragma/fisiologia , Diafragma/ultraestrutura , Eletroforese em Gel de Poliacrilamida , Masculino , Microscopia Eletrônica , Músculo Liso/ultraestrutura , Ratos , Ratos Endogâmicos
3.
FEMS Microbiol Lett ; 137(2-3): 241-5, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8998992

RESUMO

Enterotoxigenic Escherichia coli (STa+) strains were isolated from adult bovine with diarrhea. These strains did not express any known ETEC-specific adhesins. Although hemagglutination with rat and sheep erythrocytes was observed in the presence of D-mannose (MRHA), these strains also showed mannose-sensitive hemagglutination (MSHA) with guinea-pig erythrocytes. Electron microscopic studies revealed the presence of fimbria-like structures (provisionally called "F43ms") on bacterial cells grown at 37 degrees C but not on cells grown at 18 degrees C. However, it was observed by SDS-PAGE that the J-1 strain (F43ms+) produces a protein similar to F1 fimbriae, and this strain hybridized with a DNA probe for F1 fimbriae. Immunogold-labelling techniques indicated that a rabbit anti-serum is specific for F43ms fimbrial structures, but not for Type 1 fimbriae. The immunofluorescence test carried out with semipurified F43ms on bovine brush borders suggests that the fimbria-like structures are responsible for the adhesion to bovine epithelial cells.


Assuntos
Aderência Bacteriana/fisiologia , Escherichia coli/fisiologia , Fímbrias Bacterianas/fisiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Escherichia coli/isolamento & purificação , Escherichia coli/ultraestrutura , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Fímbrias Bacterianas/ultraestrutura , Cobaias , Hemaglutinação/efeitos dos fármacos , Humanos , Técnicas In Vitro , Manose/farmacologia , Microscopia Eletrônica , Coelhos , Ratos , Ovinos
4.
Heart ; 76(4): 337-43, 1996 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-8983681

RESUMO

OBJECTIVE: In congestive heart failure (CHF) the skeletal muscle of the lower limbs develops a myopathy with atrophy and shift from the slow type to the fast type fibres. The aim was to test the hypothesis that this myopathy is specific and not simply related to detraining, by comparing patients with different degrees of CHF with patients with severe muscle atrophy due to disuse. DESIGN: Case-control study involving 50-150 micrograms needle biopsies of the gastrocnemius muscle. By an electrophoretic micromethod, the three isoforms of myosin heavy chains (MHC) were separated. PATIENTS: Five patients restricted to bed for more than one year because of stroke with disuse atrophy and normal ventricular function, and 19 with CHF were studied. There were seven age matched controls. MAIN OUTCOME MEASURES: The percentage of MHC1 (slow isoform), MHC2a (fast oxidative), and MHC2b (fast glycolytic) was determined by densitometric scan and correlated with indices of severity of cardiac failure. RESULTS: Ejection fraction was 42.5 (SD 15.2)% in CHF, 59.5 (1.0)% in disuse atrophy and 60.3 (1.4)% in controls (P < 0.001 v both). The degree of muscle atrophy as calculated by the body mass index/gastrocnemius cross sectional area, showed a profound degree of atrophy in patients with muscle disuse [0.94 (0.39)]. This was worse than in the controls [4.27 (0.16), P < 0.0005] and the CHF patients [2.60 (1.10), P < 0.005]. Atrophy in CHF patients was also greater than in controls (P < 0.005). MHC1 was lower in CHF than in disuse atrophy [51.83 (15.04) v 84.5 (17.04), P < 0.01] while MHC2b was higher [23.5 (7.4) v 7.25 (7.92), P < 0.001]. There was a similar trend for MHC2a [24.83 (15.01) v 8.25 (9.12), P < 0.05]. Within the CHF group there was a positive correlation between NYHA class and MHC2a (r = 0.47, P < 0.05) and MHC2b (r = 0.55, P < 0.01) and a negative correlation between NYHA class and MHC1 (r = -0.74, P < 0.001). Similarly, significant correlations were found for ejection fraction, diuretic consumption score, exercise test tolerance, and degree of muscle atrophy. CONCLUSIONS: The CHF myopathy appears to be specific and not related to detraining. The magnitude of MCH redistribution correlates with the severity of the disease. The electrophoretic micromethod used is very sensitive and reproducible. Biopsies are so well tolerated that can be repeated frequently, allowing thorough follow up.


Assuntos
Insuficiência Cardíaca/metabolismo , Músculo Esquelético/química , Atrofia Muscular/metabolismo , Cadeias Pesadas de Miosina/análise , Idoso , Idoso de 80 Anos ou mais , Diuréticos/uso terapêutico , Eletrocardiografia , Eletroforese , Tolerância ao Exercício , Feminino , Insuficiência Cardíaca/tratamento farmacológico , Humanos , Masculino , Pessoa de Meia-Idade
5.
In Vitro Cell Dev Biol Anim ; 30A(2): 131-3, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8012655

RESUMO

A large bulk of experimental evidence (15) suggests that myogenic cell transfer can be regarded as a promising therapeutic approach in the cure of inherited pathologies. In particular, it has been shown that primary myoblasts obtained from embryonic or neonatal muscles allows the recovery of the normal phenotype in defective muscle tissues. The utilization of this approach in clinical settings still bears heavy limitations. Apart from the legal and ethical difficulties, the use of muscles obtained from aborted fetus is challenged by a large risk of rejection, due to the incompatibility between donor and recipient. In this context based on the genetic alteration and reimplanting of the patient's own satellite cells, appears an approach attractive. Myoblasts derived from satellite cells are the obligate candidates for experiments, but the production of sufficient cell numbers is a major problem. Local anesthetics [Bupivacaine (1-n-butyl-DL-piperidine-2-carboxylic acid-2, 6-dimethyl anilide hydrochloride) and related molecules] had been used to induce myofiber damage (and thus satellite cells proliferation) and thereby may represent a tool for increasing the yield of myoblasts from adult muscles (1,9,17). We will show that satellite cells obtained from adult muscles after bupivacaine injection can be transfected in vitro and that the transfected gene is expressed in vitro and in vivo, after reimplantation of the modified myoblasts in recipient muscles.


Assuntos
Bupivacaína/farmacologia , Expressão Gênica , Técnicas de Transferência de Genes , Músculos/fisiologia , Regeneração , beta-Galactosidase/genética , Animais , Células Cultivadas , Músculos/citologia , Músculos/transplante , Ratos , Ratos Wistar
6.
Braz J Med Biol Res ; 36(11): 1495-9, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14576905

RESUMO

Enterohemolysin produced by Escherichia coli associated with infant diarrhea showed characteristics similar to those of thiol-activated hemolysins produced by Gram-positive bacteria, including inactivation by cholesterol, lytic activity towards eukaryotic cells and thermoinstability. However, enterohemolysin activity was not inactivated by oxidation or by SH group-blocking agents (1 mM HgCl2, 1 mM iodoacetic acid) and the hemolysin (100 microg/ml) was not lethal to mice, in contrast to the lethality of the thiol-activated hemolysin family to animals. Earlier reports showed that intravenous injection of partially purified streptolysin O preparations (0.2 microg) was rapidly lethal to mice. These results suggest that E. coli enterohemolysin is not a thiol-activated hemolysin, despite its ability to bind cholesterol, probably due to the absence of free thiol-group(s) that characterize the active form of the thiol-activated hemolysin molecule.


Assuntos
Toxinas Bacterianas/isolamento & purificação , Eritrócitos/efeitos dos fármacos , Escherichia coli/química , Células Eucarióticas/efeitos dos fármacos , Proteínas Hemolisinas/isolamento & purificação , Animais , Toxinas Bacterianas/toxicidade , Membrana Celular , Colesterol/metabolismo , Eletroforese em Gel de Poliacrilamida , Proteínas de Escherichia coli , Proteínas Hemolisinas/toxicidade , Hemólise , Masculino , Camundongos , Ligação Proteica
7.
Rev Inst Med Trop Sao Paulo ; 38(6): 401-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-9293085

RESUMO

The mannose-resistant hemagglutinating factor (HAF) was extracted and purified from a diffuse adherent Escherichia coli (DAEC) strain belonging to the classic enteropathogenic E. coli (EPEC) serotype (0128). The molecular weight of HAF was estimated to be 18 KDa by SDS-PAGE and 66 KDa by Sephadex G100, suggesting that the native form of HAF consists of 3-4 monomeric HAF. Gold immunolabeling with specific HAF antiserum revealed that the HAF is not a rigid structure like fimbriae on the bacterial surface. The immunofluorescence test using purified HAF on HeLa cells, in addition to the fact that the HAF is distributed among serotypes of EPEC, suggests that HAF is a possible adhesive factor of DAEC strains.


Assuntos
Adesinas de Escherichia coli/isolamento & purificação , Aderência Bacteriana , Escherichia coli/isolamento & purificação , Hemaglutinação , Escherichia coli/patogenicidade , Imunofluorescência , Humanos , Peso Molecular
8.
Neuroscience ; 168(3): 670-9, 2010 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-20416363

RESUMO

Previous evidence from functional magnetic resonance imaging (fMRI) studies has shown that amygdala responses to emotionally neutral pictures are exaggerated at a group level in patients with severe post-traumatic stress disorder (PTSD) [Hendler T, Rotshtein P, Yeshurun Y, Weizmann T, Kahn I, Ben-Bashat D, Malach R, Bleich A (2003) Neuroimage 19(3):587-600]. The present fMRI study tested the hypothesis that amygdala responses are elevated not only in response to negative pictures but also to neutral pictures as a function of disease severity in patients with mild symptoms and in subjects who did not develop symptoms. To this end, fMRI scans were performed in 10 patients with mild PTSD and 10 healthy controls (both victims of a bank robbery), during the execution of a visuo-attentional task in which they were asked to observe emotionally negative or neutral pictures. Control subjects showed enhanced amygdala responses to emotionally negative stimuli compared to neutral stimuli. On the contrary, PTSD patients were characterized by high amygdala responses to both neutral and emotional pictures, with no statistically significant difference between the two classes of stimuli. In the entire group, we found correlations among the severity of the PTSD symptoms, task performance, and amygdala activation during the processing of neutral stimuli. Results of this study suggest that amygdala responses and the selectivity of the emotional response to neutral stimuli are elevated as a function of disease severity in PTSD patients with mild symptoms.


Assuntos
Tonsila do Cerebelo/fisiopatologia , Emoções , Transtornos de Estresse Pós-Traumáticos/fisiopatologia , Adulto , Medo , Feminino , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Estimulação Luminosa , Índice de Gravidade de Doença , Transtornos de Estresse Pós-Traumáticos/psicologia
11.
Biochem Biophys Res Commun ; 116(3): 793-802, 1983 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-6651845

RESUMO

Myosin isoforms are used as markers of heterogeneity and plasticity of skeletal muscle fibers and motor units. Tedious and time-consuming methods, needing microgram or milligram amounts of myosin are widely used to characterize the heavy subunits. We here describe a sensitive method that separates in nanogram or microgram amounts the heavy chains of immature, fast and slow adult rat muscles in complex mixtures of myosins. Though the method is assembled from published procedures (SDS-PAGE, peptide mapping in the presence of SDS, silver stain) for the logical extensions introduced the end-product is a powerful tool to separate and characterize these high molecular weight biopolymers until now inseparable from complex mixtures. The method reveals the heterogeneous nature of the embryonic myosin heavy chains.


Assuntos
Músculos/embriologia , Miosinas/isolamento & purificação , Animais , Eletroforese em Gel de Poliacrilamida/métodos , Feminino , Masculino , Músculo Liso/análise , Músculo Liso/embriologia , Músculos/análise , Gravidez , Ratos , Ratos Endogâmicos , Dodecilsulfato de Sódio
12.
Anal Biochem ; 213(1): 34-9, 1993 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8238879

RESUMO

Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in the discontinuous system of Laemmli is used world-wide for analytical and preparative gel electrophoresis of polypeptides. A minor but disturbing problem is the difficulty of concentrating highly diluted solutions and determining their protein content after 2-mercaptoethanol-SDS solubilization. We describe a solution to both of these problems, detailing a two-step procedure which takes advantage of the low solubility of potassium dodecyl sulfate (KDS). Removal of excess of SDS and 2-mercaptoethanol, and concentration of proteins from even a nanomolar solution, is achieved by a two-step KDS precipitation. Free dodecyl sulfate is precipitated in step one, while KDS-proteins are pelleted in the second step, allowing the thiol agents to be discarded with the supernatant. The effects of changing [SDS] and [KC1], temperature, and pH were studied to optimize the separation of free SDS from proteins. After final precipitation, the hundred- or thousandfold concentrated proteins can be suspended in a small volume of any required medium. The procedure allows protein determination by the Lowry method, peptide mapping of 2-mercaptoethanol-SDS-solubilized polypeptides, and all other analyses which are otherwise hampered by excesses of SDS and/or thiol reagents.


Assuntos
Mercaptoetanol/isolamento & purificação , Proteínas/isolamento & purificação , Dodecilsulfato de Sódio/isolamento & purificação , Animais , Precipitação Química , Técnicas de Química Analítica/métodos , Dodecanol , Eletroforese em Gel de Poliacrilamida/métodos , Concentração de Íons de Hidrogênio , Potássio , Proteínas/análise , Ratos , Solubilidade , Temperatura
13.
Cell Biol Int ; 17(11): 979-83, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8111346

RESUMO

The local anaesthetic (Bupivacaine (1-n-butyl-DL-piperidine-2-carboxylic acid-2, 6-dimethyl anilide hydrochloride) has been used to induce myofiber damage (and thus satellite cells proliferation) and thereby represents a tool for increasing the yield of myoblasts from adult muscles. Replicating satellite cells were isolated by enzymatic dissociation from soleus (slow type) and tibialis anterior (fast type) muscles of adult rats, and categorized by the isoform (embryonic, fast and slow) of myosin heavy chain (MHC) expressed following myotube formation in a similar in vitro environment. According to light microscopic criteria, no morphological differences exist between the satellite cell cultures obtained from adult fast and slow muscles after Bupivacaine injection. On the other hand the derived myotubes express, beside the embryonic type, the peculiar myosin heavy chains which characterize the myosin pattern of the donor muscles.


Assuntos
Músculos/fisiologia , Miosinas/biossíntese , Animais , Bupivacaína/toxicidade , Células Cultivadas , Eletroforese em Gel de Poliacrilamida , Expressão Gênica , Immunoblotting , Músculos/efeitos dos fármacos , Músculos/patologia , Miosinas/análise , Miosinas/isolamento & purificação , Ratos , Ratos Wistar , Regeneração
14.
Eur J Biochem ; 193(3): 623-8, 1990 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-2249683

RESUMO

The total content of myosin heavy chains (MHC) and their isoform pattern were studied by biochemical methods in the slow-twitch (soleus) and fast-twitch (extensor digitorum longus) muscles of adult rat during atrophy after denervation and recovery after self-reinnervation. The pattern of fibre types, in terms of ultrastructure, was studied in parallel. After denervation, total MHC content decreased sooner in the slow-twitch muscle than in the fast-twitch. The ratio of MHC-1 and the MHC-2B isoforms to the MHC-2A isoform decreased in the slow and the fast denervated muscles, respectively. After reinnervation of the slow muscle, the normal pattern of MHC recovered within 10 days and the type 1 isoform increased above the normal. In the reinnervated fast muscle, the 2B/2A isoform ratio continued to decrease. Traces of the embryonic MHC isoform, identified by immunochemistry, were found in both denervated and reinnervated slow and fast muscles. A shift in fibre types was similar to that found in the MHC isoforms. Within 2 months of recovery a tendency to normalization was observed. The results show that (a) MHC-2B isoform and the morphological characteristics of the 2B-type muscle fibres are susceptible to lack of innervation, similar to those of type 1, (b) during muscle recovery induced by reinnervation the MHC isoforms and muscle fibres shift transiently to type 1 in the soleus and to type 2A in the extensor digitorum longus muscles, and (c) the embryonic isoform of MHC may appear in the adult skeletal muscles if innervation is disturbed.


Assuntos
Denervação Muscular , Músculos/inervação , Miosinas/metabolismo , Regeneração Nervosa , Animais , Eletroforese em Gel de Poliacrilamida , Feminino , Cinética , Músculos/fisiologia , Miosinas/isolamento & purificação , Compressão Nervosa , Tamanho do Órgão , Ratos , Ratos Endogâmicos
15.
Epilepsia ; 30(6): 807-12, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2512116

RESUMO

Forty patients with partial epilepsy that began before they were aged 3 years were recorded at the Centre Saint-Paul between 1981 and 1986 with a follow-up ranging from 1 year 9 months to 20 years. We analyzed the following data: age at onset, clinical features of seizures at onset and during the follow-up period, ictal and interictal EEG features, etiologic circumstances, evolution of the epilepsy, and psychomotor development. The age of onset was mostly between 2 months and 2 years (more than two thirds of cases). Most had partial symptomatic epilepsy. In nine cases, epilepsy was preceded by febrile convulsions. Seizures at onset were of the following type (in order of decreasing occurrence): unilateral seizures, complex partial seizures, elementary partial seizures, and other seizures, often difficult to classify. A few patients with infantile spasms associated with focal or multifocal EEG abnormalities, differing from West's syndrome, were included in this study. We discuss the problem arising from the classification of infantile seizures and epilepsies.


Assuntos
Epilepsias Parciais/fisiopatologia , Pré-Escolar , Eletroencefalografia , Epilepsias Parciais/etiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Prognóstico , Desempenho Psicomotor , Estudos Retrospectivos , Convulsões Febris/complicações
16.
Biochem J ; 282 ( Pt 1): 237-42, 1992 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-1540139

RESUMO

The myosin heavy-chain (MHC) isoform pattern was studied by biochemical methods in the slow-twitch (soleus) and fast-twitch (gastrocnemius) muscles of adult rats during atrophy after tenotomy and recovery after tendon regeneration. The tenotomized slow muscle atrophied more than the tenotomized fast muscle. During the 12 days after tenotomy the total MHC content decreased by about 85% in the slow muscle, and only by about 35% in the fast muscle. In the slow muscle the ratio of MHC-1 to MHC-2A(2S) remained almost unchanged, showing that similar diminution of both isoforms occurs. In the fast muscle the MHC-2A/MHC-2B ratio decreased, showing the loss of MHC-2A mainly. After tendon regeneration, the slow muscle recovered earlier than the fast muscle. Full recovery of the muscles was not observed until up to 4 months later. The embryonic MHC, which seems to be expressed in denervated adult muscle fibres, was not detected by immunoblotting in the tenotomized muscles during either atrophy or recovery after tendon regeneration. The influence of tenotomy and denervation on expression of the MHC isoforms is compared. The results show that: (a) MHC-1 and MHC-2A(2S) are very sensitive to tenotomy, whereas MHC-2B is much less sensitive; (b) expression of the embryonic MHC in adult muscle seems to be inhibited by the intact neuromuscular junction.


Assuntos
Músculos/fisiologia , Miosinas/metabolismo , Tendões/fisiologia , Animais , Atrofia , Feminino , Cinética , Músculos/metabolismo , Músculos/patologia , Ratos , Ratos Endogâmicos , Valores de Referência , Regeneração , Tendões/cirurgia , Fatores de Tempo
17.
Exp Neurol ; 79(1): 106-17, 1983 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-6822248

RESUMO

We examined myosin of fast and slow skeletal rat muscles regenerating after ischemia and bupivacaine injection in denervated limbs. Four days after injury two-dimensional gel electrophoresis revealed the presence of the embryonic light chain in the myosin isolated from the portion of muscle showing a homogeneous population of new small fibers by histological examination. Two weeks after injury this subunit was absent, whereas the two light chains, LC1F and LC2F, became prominent. One month after injury the still denervated soleus muscle maintained this light chain pattern. Gel electrophoresis in native condition of the myosin and peptide mapping of electrophoretically purified heavy chains confirmed that the muscle regenerating in absence of the nerve accumulated a myosin that had the general features of a fast, not slow, myosin but contained definite differences from the former.


Assuntos
Músculos/fisiologia , Miosinas/classificação , Regeneração , Animais , Eletroforese , Masculino , Denervação Muscular , Músculos/análise , Músculos/embriologia , Miosinas/análise , Peptídeos/análise , Ratos , Ratos Endogâmicos , Fatores de Tempo , Distribuição Tecidual
18.
J Muscle Res Cell Motil ; 2(3): 335-42, 1981 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7287900

RESUMO

The myosin light chains of slow muscles from different species have been examined two-dimensional gel electrophoresis. While the myosin light chain 2S of mammalian soleus muscles (rabbit, rat and guinea-pig) could not be distinguished from that of avian anterior latissimus dorsi (chicken and turkey), the 1S light chain complement of myosins shows inter- and intraspecific differences. The 1S light chain varies between birds and mammals. The 1S light chain is absent in avian slow myosins and has an electrophoretic mobility peculiar to each mammalian species. Furthermore the relative amount of 1S and 1S light chains varies in different muscles of the same mammalian species and among species.


Assuntos
Músculos/metabolismo , Miosinas/metabolismo , Actinas/metabolismo , Actomiosina/metabolismo , Animais , Fenômenos Químicos , Química , Galinhas , Diafragma , Eletroforese em Gel de Poliacrilamida , Cobaias , Coelhos , Ratos , Especificidade da Espécie , Tropomiosina/metabolismo , Perus
19.
Biochem Biophys Res Commun ; 202(3): 1688-96, 1994 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-8060358

RESUMO

We used an in vitro model to investigate whether macrophages stimulate satellite cells proliferation. Satellite cells were obtained by tryptic digestion of adult muscle. Macrophages were obtained from peritoneal cavity by wash after injection of thioglycolate broth. Macrophages and satellite cells cocultures showed an increased number of differentiated myotubes as compared to control cultures. Moreover, in conditions of myoblast colony growth, the addition of macrophage-conditioned medium resulted in a greater number of muscle cell colonies, which are richer in large and differentiated myotubes. The experiments with macrophage-conditioned media suggest that the increased muscle cell proliferation and differentiation is mediated by soluble factor(s) released by macrophages. These results demonstrate that besides their scavenger role macrophages play a pivotal role in myoblast proliferation during muscle regeneration.


Assuntos
Macrófagos Peritoneais/fisiologia , Músculos/citologia , Animais , Diferenciação Celular/fisiologia , Divisão Celular/fisiologia , Células Cultivadas , Ratos
20.
Exp Neurol ; 94(3): 537-53, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3780906

RESUMO

Adult fast and slow skeletal muscles are composed of a large number of fibers with different physiological and biochemical properties that under neuronal control can respond in a plastic manner to a variety of stimuli. Although muscle cells synthesize muscle-specific contractile proteins in the absence of motoneurons, after innervation the neuron controls the particular set of isoforms subsequently synthesized. However, agreement has not been reached on the mechanism, either chemotrophic or impulse-mediated, by which the nerve influences gene expression in the muscle. Here we report the effect on isomyosins of continuous, low-frequency (a protocol mimicking the discharge pattern of the slow motoneuron) direct electrical stimulation of a permanently denervated fast muscle, the extensor digitorum longus of adult rat. After several weeks, unlike sham-stimulated muscle, the stimulated muscle showed a dramatic increase of the slow myosin light and heavy chains. Myosin light chains were identified by two-dimensional gel electrophoresis. The slow myosin heavy chain was clearly distinguished from fast and embryonic types by one-dimensional sodium dodecyl sulfate-polyacrylamide gel electrophoresis and orthogonal peptide mapping. The myosin change could be restricted to a portion of the muscle by the position of the stimulating electrodes. Taking into account the morphologic appearance of the electrostimulated muscle and the large body of evidence demonstrating the absolute dependence of slow myosin on specific innervation, our observations indicate that at least the slow motoneuron influences the isomyosin genes' expression by the kind of activity it imposes on developing muscle fibers.


Assuntos
Músculos/fisiologia , Miosinas/metabolismo , Animais , Estimulação Elétrica , Eletroforese em Gel de Poliacrilamida , Masculino , Neurônios Motores/fisiologia , Denervação Muscular , Mapeamento de Peptídeos , Ratos , Ratos Endogâmicos
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