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1.
Encephale ; 41(4): 332-8, 2015 Sep.
Artigo em Francês | MEDLINE | ID: mdl-25998989

RESUMO

OBJECTIVE: To assess involuntary admitted patients' experience and understanding of their hearing with the judge ruling on civil detention cases according to the Act of July 5th 2011. METHODS: The evaluation was conducted through face-to-face interviews, from a semi-structured questionnaire, with 48 involuntary admitted patients under psychiatric care admission on a third party request (ASPDT) or on state representative decision (ASPDRE) (participation rate=96%). RESULTS: Few participants knew the name of the hearing place (13%) and the judge's exact title (21%). About 58% of them had benefited from lawyer services. During the hearing, half of the patients contested the need for hospitalization. The judge was perceived as clear (79%), listening (69%) and benevolent (58%), but only 46% of patients believed that he/she was impartial and 35% that he/she was independent from medical decisions. More than half of the patients disagreed with the judge's decision (56%). However, only 19% of them planned to appeal. Three out of four were in favour of a judicial review of involuntary hospitalization. A feeling of protection was more common in people with a higher educational level (65% versus 35%, Chi(2) (1) = 3.9, P = 0.05) and who suffered from mood disorders (75% versus 46%, Chi(2) (1) = 3.8, P = 0.05). A feeling of being accused was more frequent in persons with hospitalization under psychiatric care admission on state representative decision (ASPDRE) than on a third party request (ASPDT) (37% vs 10%, Chi(2) (1) = 4.9, P = 0.03). Persons under guardianship were also more likely to report such feelings (32% versus 10%, Chi(2) (1) = 3.4, P=0.06). The feeling that "everything was preordained" was more common in younger patients (m = 36.4 years [SD = 13.9] vs m = 46.2 years [SD = 17.8], t-test [46] = 2.01, P = 0.04), as well as among those who used the advice of a lawyer, with an association at a trend level (73% versus 46%, Chi(2) (1) = 3.5, P = 0.06). CONCLUSION: Systematic judicial review of involuntary hospitalization represents a major evolution in the patients' rights field. This study shows that their experience and understanding of the hearing with the judge ruling on civil detention cases are quite mixed. In clinical practice, informing the patient about the upcoming hearing may allow the physician who initiates the hospitalization to reassure him/her as the intervention of a third party will be required to confirm the legality of involuntary admission. Furthermore, such information about the judicial intervention might avoid unproductive confrontation between the patient and the physician when the person remains opposed to the hospitalization. However, some patients may be disappointed as they are heavily invested in the preparation of their "defence" and have high hopes in the intervention of a judge who most often maintains the hospitalization.


Assuntos
Internação Compulsória de Doente Mental/legislação & jurisprudência , Transtornos Mentais/terapia , Direitos do Paciente/legislação & jurisprudência , Adulto , Escolaridade , França , Humanos , Entrevistas como Assunto , Transtornos Mentais/diagnóstico , Pessoa de Meia-Idade , Inquéritos e Questionários
2.
J Gerontol A Biol Sci Med Sci ; 70(2): 163-73, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24550352

RESUMO

Aging is usually accompanied by a significant reduction in muscle mass and force. To determine the relative contribution of inactivity and aging per se to this decay, we compared muscle function and structure in (a) male participants belonging to a group of well-trained seniors (average of 70 years) who exercised regularly in their previous 30 years and (b) age-matched healthy sedentary seniors with (c) active young men (average of 27 years). The results collected show that relative to their sedentary cohorts, muscle from senior sportsmen have: (a) greater maximal isometric force and function, (b) better preserved fiber morphology and ultrastructure of intracellular organelles involved in Ca(2+) handling and ATP production, (c) preserved muscle fibers size resulting from fiber rescue by reinnervation, and (d) lowered expression of genes related to autophagy and reactive oxygen species detoxification. All together, our results indicate that: (a) skeletal muscle of senior sportsmen is actually more similar to that of adults than to that of age-matched sedentaries and (b) signaling pathways controlling muscle mass and metabolism are differently modulated in senior sportsmen to guarantee maintenance of skeletal muscle structure, function, bioenergetic characteristics, and phenotype. Thus, regular physical activity is a good strategy to attenuate age-related general decay of muscle structure and function (ClinicalTrials.gov: NCT01679977).


Assuntos
Envelhecimento/fisiologia , Exercício Físico/fisiologia , Fibras Musculares Esqueléticas/ultraestrutura , Músculo Esquelético/fisiologia , Adulto , Idoso , Biópsia por Agulha , Cálcio/metabolismo , Teste de Esforço , Humanos , Fator de Crescimento Insulin-Like I/genética , Contração Isométrica/fisiologia , Masculino , Proteínas de Membrana/metabolismo , MicroRNAs/genética , Microscopia Eletrônica de Transmissão , Mitocôndrias Musculares/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/patologia , Fator 2 Relacionado a NF-E2/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Isoformas de Proteínas/genética , Proteínas Proto-Oncogênicas/metabolismo , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA/metabolismo , Comportamento Sedentário , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Fatores de Transcrição/metabolismo , Regulação para Cima/fisiologia , Fator de Transcrição YY1/metabolismo , Adulto Jovem
3.
Int J Artif Organs ; 26(3): 217-24, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12703888

RESUMO

PURPOSE: The value of dynamic cardiomyoplasty has been brought into question by the disappointing results produced by slow contraction-relaxation cycle and possibly degeneration of the latissimus dorsi muscle (LD) secondary to temporary tenotomy and chronic daily electrical stimulation. Objective of our study is to determine whether daily periods of rest introduced by demand stimulation in the continuous contraction protocol produce systolic assistance and improve clinical results. METHODS: Twelve dynamic cardiomyoplasty patients (mean age 58.2 +/- 5.8 years, M/F=11/1, sinus rhythm/atrial fibrillation=11/1) with dilated myocardiopathy were enrolled in an unrandomized trial of Demand Dynamic Heart Bio-Girdling in a public regional teaching hospital. Periods of LD inactivity, each lasting several hours, were introduced daily on a heart rate-based demand regime. To avoid full transformation of LD, fewer impulses per day were delivered, daily providing the LD with long periods of rest (Demand light stimulation). The contractile properties were measured by transcutaneous non-invasive LD tensiomyogram interrogation (LD tensiomyogram). Bio-Girdle activation was synchronized to heart beat by combining tensiomyogram and echocardiography. Clinical, echocardiographic and hemodynamic records, as well as aortic flow measurements by Doppler aortic flow wire were taken during the follow-up. MAIN FINDINGS: Mean duration of the demand stimulation follow-up was 40.2+13.8 months. At five years, "Demand stimulation" shows: 1) no operative death; 2) 83% actuarial survival; 3) highly significant 47.4% decrease of the NYHA class (from 3.17 +/- 0.38 to 1.67 +/- 0.77, p=0.0001); 4) 41.6% improvement of LVEF (from 22.6 +/- 4.38 to 32.0 +/- 7.0, p=0.001); 5) 7.5 +/- 3.0% increase in aortic flow velocity peak in assisted vs. unassisted beats, and 6) preservation of LD from slowness (TFF value 33 +/- 7.86 at follow-up versus 15.8 +/- 11.1 Hz just before switching from continuous to demand stimulation, p=0.0001) and muscle degenerative atrophy. CONCLUSIONS: In dynamic cardiomyoplasty the demand light stimulation maintains LD contraction properties over time, produces effective systolic assistance, and improves clinical results. Demand dynamic bio-girdling is a safe and effective treatment for end-stage heart failure in selected patients.


Assuntos
Cardiomiopatia Dilatada/cirurgia , Cardiomioplastia/métodos , Estimulação Elétrica/métodos , Músculo Esquelético/fisiologia , Aorta/fisiopatologia , Ecocardiografia Doppler , Feminino , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Contração Muscular/fisiologia , Músculo Esquelético/inervação , Miografia , Descanso/fisiologia , Resultado do Tratamento
4.
Circulation ; 103(17): 2195-200, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11331262

RESUMO

BACKGROUND: In congestive heart failure (CHF), skeletal muscle shows increased expression of fast myosin heavy chains (MHC) and fibers, muscle atrophy, increased fatigability, and decreased endurance. Atrophy is secondary to myocyte apoptosis, which is probably triggered by tumor necrosis factor-alpha (TNFalpha). Angiotensin II receptors are thought to play a role in controlling apoptosis. We tested the hypothesis that angiotensin II receptor blockade could prevent skeletal muscle apoptosis in rats with CHF. METHODS AND RESULTS: CHF was induced by injecting 36 rats with 30 mg/kg monocrotaline. Ten additional animals were injected with saline and acted as controls. After 2 weeks, 18 of the 36 rats with CHF were treated with 7 mg. kg(-1). d(-1) irbesartan through osmotic minipumps, and 10 of the 36 rats were treated with 2 mg. kg(-1). d(-1) nifedipine in drinking water. After 2 additional weeks, rats were killed. Tibialis anterior cross-sectional area, MHC composition, myocyte apoptosis, Bcl-2, pro-caspase 3, and activated caspases 3 and 9 were determined, as were plasma levels of TNFalpha and angiotensin II. Myocyte apoptosis and muscle atrophy were significantly decreased with irbesartan compared with untreated CHF rats. Irbesartan-treated rats had fewer cells labeled positively with terminal deoxynucleotidal transferase-mediated dUTP nick-end labeling and fewer caspases; however, they also had increased Bcl-2 levels and muscle fiber cross-sectional areas. The MHC pattern in irbesartan-treated animals was similar to that in controls. Nifedipine animals behaved like the untreated CHF animals. Angiotensin II was increased 3- to 4-fold in all CHF rats (treated and untreated). TNFalpha levels were decreased in irbesartan-treated rats but not in nifedipine-treated rats. CONCLUSIONS: Angiotensin II receptor blockade can protect from the development of apoptosis-dependent atrophy and from changes in MHCS: The reduction of TNFalpha may play a role in this process.


Assuntos
Compostos de Bifenilo/farmacologia , Músculo Esquelético/efeitos dos fármacos , Receptor Tipo 1 de Angiotensina/efeitos dos fármacos , Tetrazóis/farmacologia , Angiotensina II/biossíntese , Angiotensina II/genética , Animais , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/uso terapêutico , Bloqueadores dos Canais de Cálcio/uso terapêutico , Avaliação Pré-Clínica de Medicamentos , Regulação da Expressão Gênica/efeitos dos fármacos , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/etiologia , Hipertensão Pulmonar/induzido quimicamente , Hipertensão Pulmonar/complicações , Hipertrofia Ventricular Direita/etiologia , Bombas de Infusão Implantáveis , Irbesartana , Masculino , Monocrotalina/toxicidade , Fibras Musculares de Contração Rápida/efeitos dos fármacos , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Fibras Musculares de Contração Lenta/patologia , Proteínas Musculares/biossíntese , Proteínas Musculares/genética , Músculo Esquelético/química , Músculo Esquelético/patologia , Atrofia Muscular/prevenção & controle , Nifedipino/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptor Tipo 1 de Angiotensina/fisiologia , Tetrazóis/uso terapêutico , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética
5.
J Leukoc Biol ; 69(3): 482-9, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11261797

RESUMO

Macrophage-muscle cell interactions are complex, and the majority is unknown. The persistence of inflammatory cells in skeletal muscle could be critical for myofiber viability. In the present paper, we show that FasL plays a role in the resolution of muscle inflammation. We analyzed inflamed muscles of normal mice treated from day 3 to day 8 with a FasL inhibitor (Fas-Ig) or with control Ig. Treated muscles were collected at 3, 5, and 10 days. The treatment with recombinant Fas-Ig protein induced a severe persistence of inflammatory cells at 5 days (115,000+/-27,838 vs. 41,661+/-6848, p<0.01) and 10 days from injury (145,500+/-40,850 vs. 5000+/-1000, p<0.001). Myofiber regeneration was highly impaired (37+/-14 vs. 252+/-28, p<0.01). Apoptosis of phagocytic cells was absent during Fas-Ig treatment (0.9+/-0.6 vs. 1300+/-150, p<0.0001), but apoptotic, mononucleated cells appeared at day 10, 2 days after the suspension of Fas-Ig administration. The time course of FasL expression during muscle inflammation, at mRNA and protein level, reveals a peak during myoblast proliferation. The peak of FasL expression coincides with the peak of apoptosis of phagocytic cells. In situ hybridization shows the co-expression of FasL and MyoD mRNA in mononucleated cells, i.e., myoblasts. Experiments on the myoblast cell culture confirmed the expression of FasL in myoblasts. The findings shown here indicate one of the pathways to control myoblast-macrophage interaction and might be relevant for the control of inflammatory cells in muscle tissue. Perhaps altering FasL expression with recombinant proteins could ameliorate inflammation in degenerative myopathies and up-regulate muscle regeneration.


Assuntos
Macrófagos/citologia , Glicoproteínas de Membrana/antagonistas & inibidores , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Animais , Apoptose/fisiologia , Comunicação Celular/fisiologia , Sobrevivência Celular/fisiologia , Técnicas de Cocultura , Proteína Ligante Fas , Imunoglobulinas/imunologia , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/imunologia , Glicoproteínas de Membrana/fisiologia , Camundongos , Fibras Musculares Esqueléticas/citologia , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Miosite/induzido quimicamente , Miosite/patologia , Receptor fas/fisiologia
6.
J Neuropathol Exp Neurol ; 60(3): 302-12, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11245214

RESUMO

Apoptosis was detected in different muscular diseases, including severe dystrophin deficiency, but apoptotic mechanisms are not completely described in adult skeletal muscle. Studying patients affected by Duchenne muscular dystrophy (DMD) and by facio-scapulo-humeral dystrophy (FSHD) we showed an increase of apoptotic myonuclei, bax, and bcl-2-positive myofibers. Positive correlation was detected between apoptotic nuclei and bax expression (p < 0.01). Expression of caspases was analyzed by RNase protection. Caspase transcript was not detected in normal skeletal muscles. DMD muscles expressed caspase 8, 3, 5, 2, 7 and Granzyme B mRNAs. Low levels of caspase 6, 3, and Granzyme B transcripts were detected in FSHD patients. Tissue levels of caspase 3 protein significantly correlated with apoptotic myonuclei (p < 0.05) and with bax expression (p < 0.01). In all DMD cases the activity of caspase 3 was increased, while the FSHD samples were heterogeneous. These data indicate that human skeletal muscle fibers. during the dystrophic process, modulate the expression of caspases and that caspase 3 is involved in myofiber cell death. opening new perspective in the pharmacological treatments of muscular dystrophies, such as the use of caspase inhibitors.


Assuntos
Apoptose , Caspases/metabolismo , Músculo Esquelético/enzimologia , Músculo Esquelético/patologia , Distrofia Muscular de Duchenne/enzimologia , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular Facioescapuloumeral/enzimologia , Distrofia Muscular Facioescapuloumeral/patologia , Adolescente , Adulto , Idoso , Caspase 3 , Criança , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Regulação para Cima , Proteína X Associada a bcl-2
7.
Muscle Nerve ; 24(1): 47-53, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11150965

RESUMO

Bupivacaine-induced regeneration was studied in rat soleus muscle under several conditions, with the focus on type 2A and type 1 myosin heavy chain (MHC) isoform expression. In denervated muscles, type 1 was absent, whereas type 2A was widely expressed, a pattern of regeneration which appeared to be independent of fibrillation activity of the muscle. Both type 1 and type 2A isoforms were absent in muscles regenerated during tetrodotoxin (TTX) block of impulse conduction in the sciatic nerve, but type 2A was still present when the TTX block was associated with the vinblastine block of axoplasmic flow; vinblastine block alone caused the coexpression of type 1 and type 2A isoforms in the majority of fibers. These results suggest that axoplasmic flow carries some chemical factor that inhibits 2A MHC isoform expression. The results are also of clinical interest, contributing to the understanding of factors controlling muscle differentiation and adaptation.


Assuntos
Fibras Musculares de Contração Lenta/metabolismo , Músculo Esquelético/inervação , Músculo Esquelético/metabolismo , Cadeias Pesadas de Miosina/biossíntese , Anestésicos Locais/farmacologia , Animais , Antineoplásicos Fitogênicos/farmacologia , Transporte Axonal/efeitos dos fármacos , Bupivacaína/farmacologia , Eletroforese em Gel de Poliacrilamida , Fasciculação/tratamento farmacológico , Feminino , Imuno-Histoquímica , Masculino , Denervação Muscular , Fibras Musculares de Contração Lenta/efeitos dos fármacos , Fibras Musculares de Contração Lenta/patologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/patologia , Procainamida/farmacologia , Isoformas de Proteínas , Ratos , Ratos Wistar , Regeneração/efeitos dos fármacos , Regeneração/fisiologia , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiologia , Nervo Isquiático/ultraestrutura , Tetrodotoxina/farmacologia , Vimblastina/farmacologia
8.
Acta Neuropathol ; 100(6): 618-26, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11078213

RESUMO

This study investigated the basis for the high severity of damage to skeletal muscle due to eccentric exercise, i.e., to muscles generating force while lengthened. Fast and slow rat leg muscles maintained in an extended position were examined after 2-24 h of continuous stimulation. The treatment caused the injury to some regions of both muscles. Within the better preserved parts of the muscles, i.e., those without signs of necrotic processes, dystrophin, spectrin, and some of the dystrophin-associated proteins (beta-dystroglycan, alpha-sarcoglycan, and gamma-sarcoglycan) disappeared from sarcolemma of many fibers. The reduction or loss of dystrophin from the sarcolemma was more evident than that of other proteins examined, with sarcoglycans apparently being the most preserved. Several muscle fibers devoid of dystrophin contained apoptotic nuclei. Simultaneously, Bax, Bcl-2 and caspase-3 proteins appeared in many fibers. Our results indicate that a normal muscle overworking in an extended position undergoes the loss of several membrane skeletal proteins because of the excessive stress to the membrane cytoskeleton, which can lead to fiber death by either apoptosis or necrosis. This experimental model may represent a good model for mimicking the pathogenetic events in several muscular dystrophies.


Assuntos
Apoptose/fisiologia , Distrofina/metabolismo , Fadiga Muscular/fisiologia , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/metabolismo , Animais , Caspase 3 , Caspases/metabolismo , Proteínas do Citoesqueleto/metabolismo , Distroglicanas , Estimulação Elétrica , Feminino , Marcação In Situ das Extremidades Cortadas/estatística & dados numéricos , Glicoproteínas de Membrana/metabolismo , Contração Muscular/fisiologia , Fibras Musculares de Contração Rápida/metabolismo , Fibras Musculares de Contração Rápida/patologia , Fibras Musculares de Contração Lenta/metabolismo , Fibras Musculares de Contração Lenta/patologia , Músculo Esquelético/lesões , Músculo Esquelético/patologia , Condicionamento Físico Animal/fisiologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Wistar , Sarcoglicanas , Proteína X Associada a bcl-2
9.
J Immunol Methods ; 239(1-2): 1-11, 2000 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-10821942

RESUMO

Autoantibodies directed against intracellular antigens can be detected by immunoblotting (IB). Due to its high sensitivity this technique has many advantages, but it can give misleading results when the specific bands are weak or blurred against the background staining. To decrease background staining, non-ionic detergents (Tween 20, Triton X-100, Nonidet P-40) are generally used as blocking agents. Moreover, these agents appear to have a renaturating action towards proteins and antigens. Tween 20 has a more pronounced renaturating effect on proteins than other detergents and thereby improves antigen-antibody binding. To evaluate the effect of Tween 20 on specific autoantibody detection by IB, we tested the sera of 162 patients with connective tissue diseases (CTDs) by adding this detergent at certain steps of the IB assay. We found that the use of Tween 20 in the IB procedure significantly improved the binding of autoantibodies to Jo-1, Scl70, (U1)RNP 68 kDa and C, Sm B/B' and D. Moreover, it increased the sensitivity for the detection of anti-Sm D peptide in systemic lupus erythematosus (SLE) sera with no decrease in specificity. In contrast, the addition of Tween 20 significantly decreased the binding of autoantibodies specific for ribosomal P proteins, La/SSB, Ro/SSA, but not the overall sensitivity and specificity of the method. We conclude that the addition of Tween 20 to standard IB is advantageous for anti-nuclear antigen antibody detection and improves the sensitivity of the method in revealing anti-Sm-positive sera in SLE. However, Tween 20 is not recommended for the detection of anti-cytoplasmic antibodies.


Assuntos
Autoanticorpos/sangue , Doenças do Tecido Conjuntivo/imunologia , Polissorbatos , Doenças do Tecido Conjuntivo/sangue , Humanos , Immunoblotting/métodos , Células Tumorais Cultivadas
10.
Muscle Nerve ; 23(1): 44-57, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10590405

RESUMO

Patients with laryngeal motor control disorders need improved dynamic glottal closure for speech and swallowing. To evaluate the functional outcome of intermittent chronic thyroarytenoid muscle stimulation in an animal model, 6 canines were implanted with bilateral Medtronic Xtrel systems containing Peterson-type electrodes in the inferior and superior portions of the thyroarytenoid muscle. Stimulation was on one side only at 60 Hz, for 5 s on and 5 s off, over 8 h, 5 days per week, up to 8 months. Monthly videorecordings were done under anesthesia to measure the voltage threshold for detectable movement on each side, and vocal fold displacement and velocity during maximal stimulation of each side. Movement thresholds were lower in the inferior portion of the thyroarytenoid muscle (P

Assuntos
Glote/fisiologia , Músculos Laríngeos/fisiologia , Animais , Fenômenos Biomecânicos , Cães , Estimulação Elétrica , Eletrodos Implantados , Eletroforese em Gel de Poliacrilamida , Feminino , Lateralidade Funcional/fisiologia , Glote/diagnóstico por imagem , Glote/metabolismo , Músculos Laríngeos/diagnóstico por imagem , Músculos Laríngeos/metabolismo , Masculino , Cadeias Pesadas de Miosina/metabolismo , Telemetria , Fatores de Tempo , Tomografia Computadorizada por Raios X , Prega Vocal/fisiologia
11.
Muscle Nerve ; 21(2): 226-32, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9466598

RESUMO

The degeneration-regeneration process was induced by bupivacaine injection in innervated, denervated, and nerve-blocked rat soleus muscles. Nerve block was obtained by superfusion of the sciatic nerve with tetrodotoxin (TTX). Two weeks after bupivacaine injection, immunohistochemical and electrophoretical analyses showed the presence of type 1 myosin heavy chain (MHC) only in innervated regenerated muscles, type 2A in innervated and denervated, but not in TTX-paralyzed muscles, and type 2X under all experimental conditions. The presence of type 1 MHC in the innervated, and its absence in both denervated and TTX-paralyzed muscles were also verified immunohistochemically 1 week after bupivacaine injection. It is concluded that the nerve impulses play a determinant role in the expression of 1 and 2A MHC isoforms in the innervated regenerating muscle. The possible causes of the absence of the type 2A MHC isoform in the TTX-paralyzed muscles are discussed.


Assuntos
Fibras Musculares de Contração Lenta/metabolismo , Cadeias Pesadas de Miosina/metabolismo , Bloqueio Nervoso , Regeneração , Animais , Eletroforese em Gel de Poliacrilamida , Histocitoquímica , Immunoblotting , Imuno-Histoquímica , Isomerismo , Denervação Muscular , Fibras Musculares de Contração Lenta/química , Fibras Musculares de Contração Lenta/fisiologia , Ratos , Ratos Wistar , Regeneração/efeitos dos fármacos
12.
Ann Thorac Surg ; 66(6): 1983-90, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9930481

RESUMO

BACKGROUND: In dynamic cardiomyoplasty electro-stimulation achieves full transformation of the latissimus dorsi (LD); therefore, its slowness limits the systolic support. Daily activity-rest could maintain partial transformation of the LD. METHODS: Sheep LD were burst-stimulated either 10 or 24 hours/day. Before and 2, 4, 6, and 12 months after stimulation, LD power output, fatigue resistance, and tetanic fusion frequency were assessed. Latissimus dorsi were biopsied at 6 months, and sheep sacrificed at 12 months. RESULTS: After 1 year of 10 hours/day stimulation LD was substantially conserved and contained large amounts of fast type myosin. From 2 months to 1 year of stimulation the power per muscle of the daily rested LD was greater than that of the left ventricle, being three to four times higher than in the 24-hour/day stimulation. CONCLUSIONS: If extended to humans, these results could be the rationale for the need of a cardiomyostimulator, whose discontinuous activity could offer to patients the long-standing advantage of a faster and powerful muscle contraction.


Assuntos
Cardiomioplastia/métodos , Animais , Terapia por Estimulação Elétrica , Contração Muscular/fisiologia , Músculo Esquelético/citologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiologia , Ovinos , Fatores de Tempo
13.
Neuropathol Appl Neurobiol ; 24(6): 518-31, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9888162

RESUMO

Apoptosis is well accepted as a type of cell death occurring in the development of mammalian muscles, but the death of adult myofibres in neuromuscular disorders and exercise-induced muscle damage is usually explained in terms of muscle necrosis. The current view that apoptosis precedes necrosis in death of dystrophin-deficient muscle fibres of mdx mouse has been well substantiated. Moreover, apoptotic myonuclei have been reported to increase in mdx mice 2 days after spontaneous exercise. To investigate the contribution of apoptosis to exercise-induced damage of normal muscle fibre a time-course analysis has been performed in adult C57BL/6 mice. Groups of five mice were sacrificed immediately after the end of the exercise, and after a rest period of 6 or 96 h. The amount of apoptosis in leg muscles was assessed by electron microscopy, by the terminal deoxynucleotidyl transferase assay and by electrophoretic detection of fragmented DNA; the expression of Bcl-2, Bax, Fas, ICE, p53 and ubiquitin was examined by immunohistochemistry and Western blot. Absent in muscles of normal 'sedentary' mice, apoptotic myonuclei peak in muscles of normal mice after a night of spontaneous wheel-running (4% +/- 3.5, immediately and 2.5% +/- 1.8 after 6 h rest, P < 0.05 vs non-runner mice); they then decrease but are present 4 days later (0.8% +/- 1.5). Satellite cells are also involved in the apoptotic process. Myofibre content of Bcl-2 decreases whereas Bax, Fas, ICE and ubiquitin modify their pattern of expression in correlation with the changes in apoptotic myonuclei. Apoptosis of endothelial cells is present after the night of wheel-running and with a twofold increase 4 days later (1.5 +/- 2.3 and 4.8 +/- 4.4 P < 0.05, respectively). Satellite cells are also involved in the apoptotic process. Thus, spontaneous running in unaccustomed mice increases the number of apoptotic nuclei in adult muscle fibres and in endothelial cells. It remains to be established whether muscle apoptosis is restricted to the repair mechanisms, as often suggested in many pathologic processes, or it is also part of pathogenesis of muscle damage. Regardless of whether these results are extended to human dystrophies, the clinical implications in terms of secondary pathogenetic mechanisms and muscle training are obvious.


Assuntos
Apoptose/fisiologia , Fibras Musculares Esqueléticas/patologia , Músculo Esquelético/patologia , Corrida/fisiologia , Animais , Western Blotting , Núcleo Celular/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Eletrônica , Fibras Musculares Esqueléticas/química , Proteínas Musculares/análise , Músculo Esquelético/fisiologia , Regeneração/fisiologia , Ubiquitinas/análise
14.
Rev. bras. odontol ; 52(6): 22-6, nov.-dez. 1995. ilus
Artigo em Português | LILACS, BBO - Odontologia | ID: lil-168371

RESUMO

Foram empregados 24 ratos machos e sob anestesia geral, dos quais o incisivo superior direito foi extraído, sendo entäo todos os animais dividos em dois grupos de 12, que receberam os seguintes procedimentos: no grupo 1 (controle), o incisivo, após a extraçäo, foi mantido durante três minutos sobre gaze umedecida em soro fisiológico e, a seguir, reimplantado em seu respectivo alvéolo. No grupo II (tratado), o incisivo, logo após a extraçäo, teve o seu ligamento periodontal aderido ao cemento, removido através de raspagem com lâmina de bisturi n§ 11. A seguir, utilizando uma cureta adaptada, o ligamento periodontal remanescente junto à parede óssea alveolar foi removido através de curetagem cuidadosa. Logo após, o dente foi reimplantado em seu alvéolo. Seis animais de cada grupo foram sacrificados aos 10 e 40 dias pós-reimplante. As peças obtidas, após processamento laboratorial de rotina, foram incluídas em parafina para possibilitar a microtomia. Os cortes semi-seriados corados em hematoxilina e eosina para estudo histomorfológico. Os resultados obtidos mostram que nos reimplantes sem o ligamento periodontal cementário e alveolar, ocorreu discreta reabsorçäo cemento-dentinária. Näo foi observada, ainda, anquilose alvéolo-dental, dentro dos períodos analisados no presente trabalho


Assuntos
Animais , Ratos , Incisivo , Ligamento Periodontal , Reimplante Dentário , Anestesia Geral
15.
Biochem Biophys Res Commun ; 216(1): 49-53, 1995 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-7488123

RESUMO

We previously showed that macrophages, besides their scavenger role, selectively induce rat myoblast proliferation in vitro by releasing soluble factors. In this paper we demonstrate a relationship between human-activated monocytes and increased human myoblast proliferation due to IL-6 autocrine secretion by satellite cells. Indeed in the supernatants of muscle cultures treated with activated monocyte-conditioned medium we show by means of an ELISA quantitation a higher autocrine secretion of IL-6 associated with increased myoblast proliferation. This suggests that a growth factor(s) secreted by activated monocytes stimulates IL-6 production by myoblasts and then regulates proliferation of satellite cells.


Assuntos
Divisão Celular/fisiologia , Interleucina-6/metabolismo , Monócitos/fisiologia , Músculos/citologia , Adulto , Animais , Células Cultivadas , Meios de Cultivo Condicionados , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoglobulina G/farmacologia , Interleucina-1/análise , Interleucina-1/metabolismo , Interleucina-6/análise , Interleucina-6/fisiologia , Lipopolissacarídeos/farmacologia , Monócitos/efeitos dos fármacos , Monócitos/imunologia , Músculos/imunologia , Ratos
16.
Cell Biochem Funct ; 13(2): 99-104, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7538914

RESUMO

Myoblasts gene-engineered in vitro and then injected in vivo are safe, efficient options for gene therapy. While isolation of satellite cells is routinely achieved, their proliferation potential in vitro remains a limiting factor for cell transplantation under clinical conditions. We have studied the role of reversible inhibition of gene expression by antisense oligonucleotides on the proliferation of the myogenic cells. Addition of antisense oligonucleotides to myoblast cultures has been used to inhibit specifically the expression of the beta 1-integrin subunit gene. Here we show that the effects of multiple pulses of a phosphorothioate oligodeoxinucleotide antisense on the attachment to substrata and on the proliferation of myoblasts are dose-dependent. The addition of antisense to rat myoblasts caused rounding up of the cells and most of the cells became detached after several days in culture. A single pulse did not show any consistent effect, while in the presence of continuously administered antisense, the relative numbers of myoblasts in the treated muscle culture increased. We have no evidence of inhibition of myoblast fusion under these conditions. On the other hand, [3H]-TdR incorporation, total DNA and total number of cells decreased in antisense-treated cultures thus demonstrating an inhibitory effect of the phosphorothioate oligonucleotides on DNA synthesis. These side-effects could be overcome by substituting the phosphorothioate by unmodified oligonucleotides, so decreasing the half-life of the antisense, but also its toxicity. The overall results suggest a potential role of integrin antisense strategy in modulating the potential of myoblasts to proliferate.


Assuntos
Integrinas/fisiologia , Músculo Esquelético/efeitos dos fármacos , Oligonucleotídeos Antissenso/farmacologia , Animais , Animais Recém-Nascidos , Sequência de Bases , Diferenciação Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Núcleo Celular , DNA/biossíntese , Técnicas In Vitro , Integrina beta1 , Integrinas/antagonistas & inibidores , Integrinas/genética , Dados de Sequência Molecular , Músculo Esquelético/citologia , Miosinas/metabolismo , Ratos , Tionucleotídeos/química
17.
Electrophoresis ; 16(1): 101-4, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7737081

RESUMO

In mammals myosin heavy chains (MHC) are polypeptides with a molecular mass of about 200 kDa whose isoforms can be identified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and immunochemistry. Electrophoretic analysis is the only method for quantitating MHC profiles in single myofibers and/or cryostat sections of biopsied muscle. We present a method for SDS-PAGE of adult rat skeletal muscle which resolves MHC into four bands: 1, 2B, 2X, and 2A from the faster to the slower migrating band. Furthermore, embryonic MHC can be also resolved in a complex mixture of isomyosins, e.g. developing or regenerating muscles. The method does not involve preparation of gradient gels or electrophoresis at low temperature. Improved reproducibility is obtained by: (i) modification of the sample buffer; (ii) use of 7% polyacrylamide in the separating gel; (iii) control of pH of running buffer by recirculation or change of the buffer during the run; and (iv) a 24 h run. The procedure is compatible with Coomassie Brilliant Blue, silver and immunoblot staining. Resolution is sufficient to permit transblotting of separated MHC after SDS-PAGE. The different isoforms are easily identified with monoclonal antibodies. The technique provides an improved method to separate MHC and quantitate MHC2X and MHCemb in complex mixtures of MHC from a few cryostat sections of normal and diseased muscle.


Assuntos
Eletroforese em Gel de Poliacrilamida/métodos , Miosinas/análise , Miosinas/química , Animais , Immunoblotting/métodos , Músculo Esquelético/química , Ratos , Dodecilsulfato de Sódio
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