RESUMO
Purified pea mitochondrial F1-ATPase reconstituted oxidative phosphorylation in both partially and completely F1-depleted bovine heart mitochondrial membranes. The isolated plant enzyme exhibited high rates of ATP synthesis when combined with bovine heart membranes, suggesting great evolutionary conservation of the ATP synthase complex in mitochondria.
Assuntos
Mitocôndrias Cardíacas/metabolismo , Mitocôndrias/enzimologia , Fosforilação Oxidativa , Plantas/enzimologia , ATPases Translocadoras de Prótons/metabolismo , Partículas Submitocôndricas/metabolismo , Animais , Bovinos , Fabaceae , Membranas Intracelulares/metabolismo , Cinética , Plantas MedicinaisRESUMO
Inclusion of lithium chloride during the process of secretion of granulocyte-macrophage colony stimulating activity (CSA) into mouse lung conditioned medium resulted in an increased production of CSA. CSA produced in the presence of lithium chloride was compared to the CSA produced in its absence by means of ammonium sulfate precipitation, Sephadex G-1CO (S) chromatography, concanavalin A-Sepharose chromatography and polyacrylamide gel electrophoresis. It was found that the two activities behaved identically, indicating that lithium-induced increase in CSA does not involve a qualitative change in the molecule of the colony stimulating factor, but reflects an increased production (or release) of a CSF molecule that is similar to the one produced in its absence.
Assuntos
Fatores Estimuladores de Colônias/metabolismo , Lítio/farmacologia , Pulmão/metabolismo , Macrófagos/metabolismo , Animais , Precipitação Química , Cloretos/farmacologia , Cromatografia em Gel , Meios de Cultura , Eletroforese em Gel de Poliacrilamida , Hematopoese/efeitos dos fármacos , Cloreto de Lítio , Pulmão/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos , Peso MolecularRESUMO
Stimulation of [3H]thymidine uptake in mouse marrow cells by a haematopoietic factor, granulocyte-macrophage colony stimulating factor from mouse lung conditioned medium, was used to follow the activity of the factor in the medium, and during its partial purification from the medium. The assay was performed in microtitre plates and found to be much easier and faster than conventional colony counting. The marrow cells were incubated in flat-bottomed plates in the presence of the factor for 5 days before labelling with [3H]thymidine (2 muCi/well, 5 Ci/mmole) for 6 h. Stimulation of the [3H]thymidine uptake was compared with the development of granulocyte-macrophage colonies in semisolid methylcellulose culture. The activity followed by both assays showed identical behaviour when subjected to ammonium sulphate precipitation, Sephadex gel filtration, concanavalin-A-Sepharose chromatography and polyacrylamide gel electrophoresis.
Assuntos
Medula Óssea/metabolismo , Fatores Estimuladores de Colônias/fisiologia , Granulócitos/metabolismo , Macrófagos/metabolismo , Animais , Células da Medula Óssea , Células Cultivadas , Fatores Estimuladores de Colônias/isolamento & purificação , Meios de Cultura , DNA/biossíntese , Granulócitos/citologia , Hematopoese , Macrófagos/citologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Timidina/metabolismoRESUMO
We describe a case of myeloneuropathy resulting from nitrous oxide abuse. MR imaging of the spine revealed symmetric abnormal signal in the posterior columns of the cervical cord. Myeloneuropathy is caused by inactivation of vitamin B12 by nitrous oxide. This syndrome can also be seen in patients with borderline vitamin B12 deficiency who have recently been anesthetized with nitrous oxide.
Assuntos
Óxido Nitroso/intoxicação , Doenças da Medula Espinal/induzido quimicamente , Transtornos Relacionados ao Uso de Substâncias/complicações , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Pescoço , Medula Espinal/patologia , Doenças da Medula Espinal/diagnóstico , Doenças da Medula Espinal/tratamento farmacológico , Vitamina B 12/antagonistas & inibidores , Vitamina B 12/uso terapêuticoRESUMO
This article provides a review of some of the muscular disorders that can arise from some of the commonly seen endocrinologic disturbances. Thyroid, parathyroid, and adrenal dysfunctions as they relate to neuromuscular symptoms are discussed. Common clinical presentations of the endocrine myopathies are highlighted, along with diagnostic evaluation and treatments.
Assuntos
Doenças do Sistema Endócrino/diagnóstico , Doenças Musculares/diagnóstico , Doenças do Córtex Suprarrenal/diagnóstico , Doenças do Córtex Suprarrenal/terapia , Diagnóstico Diferencial , Doenças do Sistema Endócrino/terapia , Humanos , Doenças Musculares/terapia , Doenças Neuromusculares/diagnóstico , Doenças Neuromusculares/terapia , Doenças das Paratireoides/diagnóstico , Doenças das Paratireoides/terapia , Prognóstico , Doenças da Glândula Tireoide/diagnóstico , Doenças da Glândula Tireoide/terapiaAssuntos
Ácidos Graxos/metabolismo , Mitocôndrias/metabolismo , Glândula Submandibular/metabolismo , Difosfato de Adenosina/farmacologia , Animais , Coenzima A/metabolismo , Glutamatos/metabolismo , Hidroxibutiratos/metabolismo , Técnicas In Vitro , Ácidos Cetoglutáricos/metabolismo , Malatos/metabolismo , Masculino , Microscopia Eletrônica , Consumo de Oxigênio , Ácidos Palmíticos/metabolismo , Polarografia , Piruvatos/metabolismo , Ratos , Glândula Submandibular/citologia , Succinatos/metabolismoAssuntos
Lipídeos/biossíntese , Glândula Submandibular/metabolismo , Animais , Isótopos de Carbono , Carnitina/metabolismo , Fracionamento Celular , Membrana Celular/metabolismo , Coenzima A/metabolismo , Inositol/metabolismo , Ligases/metabolismo , Masculino , Microssomos/metabolismo , Mitocôndrias/metabolismo , Ácidos Palmíticos/metabolismo , Fosfatidilcolinas/biossíntese , Ratos , Glândula Submandibular/enzimologia , Triglicerídeos/biossínteseRESUMO
BACKGROUND: Spheroid body myopathy (SBM) is a rare, autosomal dominant, neuromuscular disorder, which has only been previously reported in a single large kindred. Identification of the mutated gene in this disorder may provide insight regarding abnormal neuromuscular function. METHODS: The authors completed a detailed clinical evaluation on an extensive kindred diagnosed with SBM. Genome-wide linkage analysis was performed to localize the disease gene to a specific chromosomal region. Further marker genotyping and screening of a positional, functional candidate gene were completed to detect the disease-causing mutation. Pathologic analysis of muscle biopsy was performed on three individuals. Biochemical studies were performed on one muscle biopsy specimen from an affected individual. RESULTS: Linkage to chromosome 5q23-5q31 was detected with a lod score of 2.9. Genotyping of additional markers in a larger sample of family members produced a maximum lod score of 6.1 and narrowed the critical interval to 12.2 cM. Screening of the candidate gene titin immunoglobulin domain protein (TTID, also known as MYOT) detected a cytosine-to-thymine mutation in exon 2 of all clinically affected family members. Similar pathologic changes were present in all muscle biopsy specimens. Immunohistologic and biochemical analysis revealed that the TTID protein, also known as myotilin, is a component of the insoluble protein aggregate. CONCLUSIONS: A novel mutation in the TTID gene results in the clinical and pathologic phenotype termed "spheroid body myopathy." Mutations in this gene also cause limb-girdle muscular dystrophy 1A and are associated with myofibrillar myopathy.
Assuntos
Proteínas do Citoesqueleto/genética , Predisposição Genética para Doença/genética , Corpos de Inclusão/genética , Proteínas Musculares/genética , Músculo Esquelético/fisiopatologia , Doenças Musculares/genética , Mutação/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Cromossômicos/genética , Mapeamento Cromossômico , Cromossomos Humanos Par 5/genética , Conectina , Análise Mutacional de DNA , Éxons/genética , Feminino , Genes Dominantes/genética , Marcadores Genéticos/genética , Testes Genéticos , Humanos , Corpos de Inclusão/metabolismo , Corpos de Inclusão/patologia , Masculino , Proteínas dos Microfilamentos , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Linhagem , Mutação Puntual/genéticaRESUMO
Five- and six-subunit forms of F(1)-ATPase were purified from pea (Pisum sativum L. cv Homesteader) cotyledon submitochondrial particles. Apart from the usual complement of five subunits, the six-subunit enzyme contained an additional 26,500-dalton protein. Both forms of the F(1)-ATPase were used to reconstitute oxidative phosphorylation in F(1)-depleted (ASU) as well as in F(1) and oligomycin-sensitivity conferring protein (OSCP)-depleted (ASUA) bovine mitochondrial membranes. The six-subunit enzyme was considerably more efficient in reconstituting the ATP synthesis than the five-subunit enzyme. Both forms of the enzyme were also able to reconstitute the ATPase activity in ASU- as well as in ASUA-particles. There were substantial differences, however, in the oligomycin sensitivity of the ATPase bound to the ASUA-particles: 20 and 60% inhibition by oligomycin was obtained in the case of the five-subunit and six-subunit enzyme, respectively. We conclude, that the 26,500-dalton protein present in the six-subunit F(1)-ATPase is responsible for the increase in oligomycin sensitivity of the bound enzyme and functions, therefore, as the plant OSCP.
RESUMO
Purified pea (Pisum sativum) cotyledon F1-ATPase contains six subunits rather than the five usually reported for F1-ATPases. The additional 26.5 kDa (delta) subunit is shown by immunoblotting and N-terminal amino acid sequencing to be similar to bovine oligomycin-sensitivity-conferring protein (OSCP). It is concluded that the delta subunit of plant mitochondrial F1-ATPase is the plant OSCP. This OSCP subunit occurs in all mono- and di-cotyledonous species of plants tested (maize, oats, peas, potatoes, sweet potatoes and turnips).
Assuntos
Adenosina Trifosfatases/metabolismo , Fabaceae/enzimologia , Proteínas de Membrana/metabolismo , Mitocôndrias/enzimologia , Plantas Medicinais , ATPases Translocadoras de Prótons/análise , Sequência de Aminoácidos , Western Blotting , Proteínas de Transporte , ATPases Mitocondriais Próton-Translocadoras , Dados de Sequência Molecular , Homologia de Sequência do Ácido NucleicoRESUMO
2-Thioadenosine 5'-diphosphate (2-SH ADP), 2,2'-dithiobisadenosine 5'-diphosphate (2,2'-(S-ADP)2), 8-thioadenosine 5' diphosphate (8-SH ADP), and 6-mercaptopurine riboside 5'-disphosphate (6-MPRDP) were synthesized as potential affinity labels for ADP receptors on the blood-platelet membrane. The mean relative activities of these compounds in aggregating human platelets suspended in homologous plasma were 155% (2,2'-(S-ADP)2), 74% (2-SH ADP), 0.65% (8-SH ADP), and 0.08% (6-MPRDP). The mean relative activities against washed platelets were 249% (2,2"-(S-ADP)2) and 115% (2-SH ADP), whereas no aggregation occurred with 8-SH ADP or 6-MPRDP. The last two compounds were found to be weak inhibitors of ADP-induced aggregation. Therefore, thio-substitution at postition 2 followed by oxidation to a disulfide appears to be the most promising approach to further studies of affinity labelling of membrane ADP-receptors.
Assuntos
Difosfato de Adenosina/análogos & derivados , Agregação Plaquetária/efeitos dos fármacos , Difosfato de Adenosina/farmacologia , Plaquetas/efeitos dos fármacos , Plaquetas/fisiologia , Humanos , Relação Estrutura-Atividade , Compostos de Sulfidrila/síntese química , Compostos de Sulfidrila/farmacologiaRESUMO
Results are presented in several wavelengths of the sky intensity and polarization along the solar vertical at twilight, as calculated using the backward Monte Carlo method applied to spherical shell atmospheres. Molecular scattering with anisotropy of molecules, ozone absorption, and refraction are taken into account. The dependence of the intensity on the solar depression angle is in general agreement with calculations based upon single plus second order scattering, but the degree of polarization is much higher. It is verified that the molecular plus ozone atmosphere does not explain the purple light. The elongation of the Babinet neutral point from the sun is determined as a function of solar depression angle.
RESUMO
A Monte Carlo procedure, designated as FLASH, was developed for use in computing the intensity and polarization of the radiation emerging from spherical-shell atmospheres and is especially useful for investigating the sunlit sky at twilight time. The procedure utilizes the backward Monte Carlo method and is capable of computing the Stokes parameters for discrete directions at the receiver position. Both molecular and aerosol scattering are taken into account as well as ozone, aerosol, water vapor, and carbon dioxide absorption within the atmosphere. The curvature of the light path due to the changing index of refraction with altitude is taken into account. Some comparisons are made between FLASH calculations for a pure Rayleigh atmosphere, a combined Rayleigh and aerosol atmosphere, and calculations reported by other authors for plane-parallel atmospheres. The comparisons show that the FLASH calculations for spherical-shell atmospheres are in good agreement with those for plane-parallel atmospheres within the range of zenith angles for which no differences could be attributed to the difference in the geometries of the two atmospheric models.
RESUMO
Poly A+ RNA has been purified from phorbol myristate acetate stimulated mouse EL4 cells. Translation, by microinjection into frog oocytes, gave biologically active interleukin 2 (IL2) and colony stimulating factor for granulocytes and macrophages (GM-CSF). These two mRNAs were separated by centrifugation through linear sucrose gradients. The sedimentation coefficients for IL2 and GM-CSF mRNAs were found to be 11.5S and 8S respectively. The clonal and cellular morphologies induced by the oocyte material corresponded to low concentrations of authentic GM-CSF.