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1.
Clin Genet ; 92(4): 423-429, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28139846

RESUMO

SATB2-associated syndrome (SAS) is a multisystemic disorder caused by alterations of the SATB2 gene. We describe the phenotype and genotype of 12 individuals with 10 unique (de novo in 11 of 11 tested) pathogenic variants (1 splice site, 5 frameshift, 3 nonsense, and 2 missense) in SATB2 and review all cases reported in the published literature caused by point alterations thus far. In the cohort here described, developmental delay (DD) with severe speech compromise, facial dysmorphism, and dental anomalies were present in all cases. We also present the third case of tibial bowing in an individual who, just as in the previous 2 individuals in the literature, also had a truncating pathogenic variant of SATB2. We explore early genotype-phenotype correlations and reaffirm the main clinical features of this recognizable syndrome: universal DD with severe speech impediment, mild facial dysmorphism, and high frequency of craniofacial anomalies, behavioral issues, and brain neuroradiographic changes. As the recently proposed surveillance guidelines for individuals with SAS are adopted by providers, further delineation of the frequency and impact of other phenotypic traits will become available. Similarly, as new cases of SAS are identified, further exploration of genotype-phenotype correlations will be possible.


Assuntos
Anormalidades Craniofaciais/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Proteínas de Ligação à Região de Interação com a Matriz/genética , Fatores de Transcrição/genética , Adolescente , Criança , Pré-Escolar , Anormalidades Craniofaciais/fisiopatologia , Deficiências do Desenvolvimento/fisiopatologia , Exoma/genética , Feminino , Mutação da Fase de Leitura , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Lactente , Deficiência Intelectual/fisiopatologia , Masculino , Fenótipo
2.
Transfus Med ; 26(4): 285-90, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27111588

RESUMO

BACKGROUND: The high homology and opposite orientation of RH genes promote rearrangements between them and generate a large number of RHD and RHCE variants which can be inherited together. Searching of RHD-CE genotypes predicting partial antigens in donors is of interest in order to find more closely matched donors for African descent patients. This study aimed to evaluate a molecular approach to search for RhCE variants in a cohort of individuals with altered expression of D antigen and determine the association of RH variant alleles in Brazilian blood donors. METHODS: From 80,961 blood samples tested, 421 with atypical D typing results were studied. The samples were phenotyped for C, c, E, e antigens. Rh variants were identified using molecular techniques. RESULTS: All 421 samples had altered RHD alleles, being 56·3% of them partial D. Among them, 94·9% presented variant RHCE*ce and the most common associations were: RHD*weak D type 4.2.2 with RHCE*ceAR; RHD*DAR linked to RHCE*ceVS.02; RHD*weak D type 4.0 linked to RHCE*ceVS.02 and RHCE*ce (c.48C, c.105T, c.733G, c.744C, c.1025T). Among the samples with RhCE variants, 10·6% predict partial c, partial e, hr(B) - and/or hr(S) - and 100% express low prevalence antigens. CONCLUSION: Targeting individuals with altered expression of D antigen can be a good strategy for finding donors with RhCE variants. In our study 94·9% of the partial D samples revealed altered RHCE variant alleles and 5·7% of the samples with altered RHD allele predicted partial c, partial e and the lack of the high prevalence hr(B) and hr(S) antigens.


Assuntos
Alelos , Doadores de Sangue , Variação Genética , Genótipo , Sistema do Grupo Sanguíneo Rh-Hr , Brasil , Feminino , Técnicas de Genotipagem , Humanos , Masculino , Sistema do Grupo Sanguíneo Rh-Hr/sangue , Sistema do Grupo Sanguíneo Rh-Hr/genética
3.
Nat Genet ; 23(4): 433-6, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10581030

RESUMO

Human cyclic haematopoiesis (cyclic neutropenia, MIM 162800) is an autosomal dominant disease in which blood-cell production from the bone marrow oscillates with 21-day periodicity. Circulating neutrophils vary between almost normal numbers and zero. During intervals of neutropenia, affected individuals are at risk for opportunistic infection. Monocytes, platelets, lymphocytes and reticulocytes also cycle with the same frequency. Here we use a genome-wide screen and positional cloning to map the locus to chromosome 19p13.3. We identified 7 different single-base substitutions in the gene (ELA2) encoding neutrophil elastase (EC 3. 4.21.37, also known as leukocyte elastase, elastase 2 and medullasin), a serine protease of neutrophil and monocyte granules, on unique haplotypes in 13 of 13 families as well as a new mutation in a sporadic case. Neutrophil elastase (a 240-aa mature protein predominantly found in neutrophil granules) is the target for protease inhibition by alpha1-antitrypsin, and its unopposed release destroys tissue at sites of inflammation. We hypothesize that a perturbed interaction between neutrophil elastase and serpins or other substrates may regulate mechanisms governing the clock-like timing of haematopoiesis.


Assuntos
Relógios Biológicos/genética , Hematopoese/genética , Elastase de Leucócito/genética , Mutação , Neutropenia/enzimologia , Neutropenia/genética , Sequência de Bases , Mapeamento Cromossômico , Cromossomos Humanos Par 19/genética , Análise Mutacional de DNA , Primers do DNA/genética , DNA Complementar/genética , Feminino , Genes Dominantes , Humanos , Elastase de Leucócito/química , Masculino , Modelos Moleculares , Dados de Sequência Molecular , Neutropenia/sangue , Linhagem , Periodicidade , Estrutura Terciária de Proteína
4.
J Clin Invest ; 58(2): 447-53, 1976 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-956378

RESUMO

Work performance on a treadmill has been evaluated in normal and iron-deficient rats. Anemia was removed as a variable by adjusting the hemoglobin of all animals to the same concentration. At a hemoglobin compatible with normal work performance, iron-deficient animals showed a marked impairment of running ability as compared to control animals. Iron therapy corrected the disability within 4 days. Concentrations of the cytochrome pigments and myoglobin, and rates of oxidative phosphorylation with pyruvate-malate, succinate, and alpha-glycerophosphate as substrates were all reduced in mitochondrial preparations from skeletal muscle of iron-deficient rats, but only the rate of phosphorylation with alpha-glycerophosphate as substrate increased significantly and in parallel with the recovery in work performance of the iron-deficient rats treated with iron dextran.


Assuntos
Deficiências de Ferro , Músculos/fisiopatologia , Anemia Hipocrômica/metabolismo , Anemia Hipocrômica/fisiopatologia , Animais , Citocromos/análise , Masculino , Músculos/análise , Músculos/metabolismo , Miocárdio/metabolismo , Mioglobina/análise , Fosforilação Oxidativa , Esforço Físico , Ratos
5.
Biochim Biophys Acta ; 591(2): 289-97, 1980 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-7190438

RESUMO

The respiratory chain-linked external NADH dehydrogenase has been isolated from Candida utilis in highly purified form. The enzyme is soluble and has a molecular weight of approx. 1.5 x 10(6). The enzyme contains two moles of FMN per mole of enzyme and is composed of two large subunits of mol. wt. 270 000 and eight smaller subunits of mol. wt. 135 000. Iron and copper are present in the preparations, but appear to be contaminants. The enzyme catalyzes the oxidation of NADH and NADPH at nearly equal rates and reacts readily with 2,6-dichlorophenolindophenol, CoQ6 and CoQ1 derivatives as acceptors. Rotenone (10(-5) M) and seconal (10(-3) M) do not inhibit enzymatic activity.


Assuntos
Candida/enzimologia , Redutases do Citocromo/isolamento & purificação , NADH Desidrogenase/isolamento & purificação , Candida/metabolismo , Transporte de Elétrons , Eletroforese em Gel de Poliacrilamida , Precursores Enzimáticos/isolamento & purificação , Peso Molecular , NADH Desidrogenase/metabolismo
6.
Meat Sci ; 70(1): 121-31, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-22063288

RESUMO

Impact of belly thickness on processing yields and consumer evaluations of finished bacon products was measured. Before processing through a commercial facility, pork bellies (n=96 per group) were sorted into three target thickness groups: "thin" (approximately 2.0cm); "average" (approximately 2.5cm); "thick" (approximately 3.0cm). Processing yields at various production points were recorded and samples from each thickness group were evaluated by consumers for palatability characteristics and visual appearance. Bacon manufactured using "thick" bellies had the highest processing yields through the smoking and cooking phase. "Thin" bellies had the lowest slicing yields and generated the highest percentage of less valuable "#2 slices" (slice profile less than 1.9cm at any point) and "ends and pieces." Consumers found that bacon manufactured from "average" thickness bellies did not have deficiencies in palatability characteristics, but bacon manufactured from "thin" bellies lacked crispiness and bacon manufactured from "thick" bellies lacked flavor. Consumers found the lean-to-fat ratio and the visual appearance of bacon from "thick" bellies was less appealing than bacon from "thin" and "thick" bellies. Moreover, consumers showed much stronger purchase intent for bacon from "thin" and "average" bellies. Belly thickness impacted processing yield and consumer palatability evaluations of bacon. Producers need to minimize production of "thin" bellies because of reduced processing yields and "thick" bellies because of reduced consumer appeal.

7.
Meat Sci ; 71(3): 451-63, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22060920

RESUMO

Retail pork from eight US cities was obtained for quality and palatability evaluations. Boneless pork loin chops were classified into one of three quality categories - "high," "average," or "low" - with higher quality chops possessing more desirable color, marbling, juiciness, and shear force characteristics than lower quality chops. Loin chops that were enhanced (injected with solution to improve juiciness and/or tenderness) had higher (P<0.05) pH, less purge and cook loss, and higher palatability ratings compared to non-enhanced chops. Hams compared by their protein fat free (PFF) classifications showed that ham and water product received the highest (P<0.05) ratings for juiciness and tenderness, and ham with natural juices received the highest (P<0.05) texture, ham flavor intensity, and smoke flavor ratings. Bacon was compared by price/brand categories; however, the highest priced, national branded bacon (US$12.03/kg) was similar (P>0.05) for most quality and all palatability traits to the lowest priced, national branded bacon (US$6.47/kg) and the store branded bacon (US$8.30/kg) even though retail prices differed widely. Overall, there were tremendous ranges in values for these products indicating that retail pork is quite variable and that efforts to improve the quality and consistency of it must continue.

8.
Meat Sci ; 70(1): 91-7, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-22063284

RESUMO

Impact of fresh ham quality on finished ham product characteristics was evaluated. Bone-in hams destined for spiral-sliced ham manufacturing were sorted into two pH groups before processing: pH⩽5.5 and pH⩾5.6. For boneless hams, raw materials were sorted into groups with different levels of pale, soft, and exudative (PSE) product before manufacturing into sliced vacuum packaged hams: "Low PSE" (⩽5% PSE muscle), "Intermediate PSE" (20-30% PSE muscle) or "High PSE" (40-60% PSE muscle). Few differences were observed between the pH⩽5.5 and pH⩾5.6 groups in objective color measures and drip loss in bone-in spiral-sliced hams stored under refrigeration, however, after frozen storage, hams from the pH⩽5.5 group had lower L*- and a*-values and had much higher drip loss than those from the pH⩾5.6 group. Processing yields for bone-in spiral-sliced hams were similar through cooking and chilling, however, the pH⩾5.6 group had higher yields after slicing. For boneless hams, defects occurred at a greater frequency in hams formulated with a greater percentage of PSE raw materials than those with lower amounts of PSE. Differences in objective color measures and purge were minimal over the duration of storage time, but hams formulated with greater percentages of PSE raw materials were lighter in appearance and had less redness. Consumers gave lower color responses for hams formulated with "High PSE" amounts, but did not differentiate between hams manufactured with lower quantities of PSE muscle. However, when consumers directly compared packages of ham, there was distinct discrimination against hams manufactured with greater amounts of PSE. Purchase intent showed that consumers favored ham manufactured from fresh ham muscles containing low quantities of PSE tissue. Further research is needed to determine the optimal ratio of allowable PSE product in formulation that enables processors to maximize consumer appeal with the economic realities of sorting out PSE pork.

9.
Exp Hematol ; 27(7): 1139-48, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10390189

RESUMO

Using Lomb periodogram analysis we have quantified variations in the peripheral neutrophil and platelet counts of the cyclical neutropenia animal model-the grey collie. We found that the amplitudes of the oscillations in these two cell lineages vary concomitantly. Further, the power spectrum and the shape of the oscillations in the absolute neutrophil counts vary together with the amplitude of the oscillations. As the amplitude of the oscillations increases, the height of the second subharmonic increases, giving rise to a distorted oscillation with two peaks per cycle. The particular dynamics of the absolute neutrophil counts can be reproduced by a combination of a delayed peripheral feedback, representing the peripheral control of granulopoiesis through granulocyte colony stimulating factor, together with a sinusoidal input representing an oscillatory input from the pluripotential stem cells to the granulocytic lineage. The same pluripotential stem cell input is probably responsible for the sinusoidal oscillations observed in the other cell lineages.


Assuntos
Doenças do Cão/fisiopatologia , Cães/fisiologia , Hematopoese , Células-Tronco Hematopoéticas/patologia , Neutropenia/fisiopatologia , Animais , Linhagem da Célula , Modelos Animais de Doenças , Doenças do Cão/genética , Cães/genética , Endogamia , Contagem de Leucócitos , Neutropenia/genética , Neutrófilos/patologia , Periodicidade
10.
Free Radic Biol Med ; 25(1): 95-103, 1998 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-9655527

RESUMO

It is well recognized that reactive oxygen species (ROS) are formed during the reperfusion of ischemic tissues and ROS may be pathogenic in adult tissues. Although there is little information on the formation and toxicity of ROS during prenatal life, a strong association has been made between limb and possibly brain malformations and uteroplacental ischemia during fetal stages of gestation. It has been proposed that these malformations result from attack by ROS formed during the resumption of placental perfusion. Studies reported here examined formation of ROS in teratogenically sensitive limb and brain and insensitive heart before and during the period of teratogenic sensitivity. Also examined was the formation of ROS following hypoxia and reoxygenation in fetal culture and DNA hydroxylation in sensitive and insensitive fetal tissues during uteroplacental ischemia and reperfusion in vivo. Rates of formation of superoxide anion radical and hydrogen peroxide declined with increasing gestational age whereas those for hydroxyl radical increased. Hydrogen peroxide generation was greatest in insensitive heart whereas hydroxyl radical formation was significantly lower in brain than in limb or heart, which had comparable rates. Hydrogen peroxide generation, which declined significantly in fetuses, but not in membranes with gestation, failed to respond to reoxygenation in vitro. Finally, there were significant increases in DNA hydroxylation in fetal hearts and limbs, but not in brains during uteroplacental ischemia but no further significant change could be detected after reperfusion.


Assuntos
DNA/metabolismo , Feto/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Hipóxia Celular , Feminino , Idade Gestacional , Peróxido de Hidrogênio/metabolismo , Radical Hidroxila/metabolismo , Hidroxilação , Técnicas In Vitro , Oxirredução/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/fisiologia , Traumatismo por Reperfusão/metabolismo , Saco Vitelino/metabolismo
11.
J Immunol Methods ; 144(2): 265-7, 1991 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-1720443

RESUMO

During immunoblotting for detection of human IgG, rabbit antibodies to goat IgG reacted with human IgG, Fc fragments and gamma chains when these proteins were bound to nitrocellulose or Immobilon-P membranes. This reactivity could not be adsorbed with human IgG-agarose beads or blocked with fluid phase human IgG. It was readily abrogated with human IgG adsorbed to one of these membranes, indicating that new antigenic determinants were exposed and accounted for the cross-reactivity.


Assuntos
Epitopos/análise , Imunoglobulina G/imunologia , Reações Cruzadas , Humanos , Immunoblotting , Fragmentos Fc das Imunoglobulinas/imunologia
12.
Neuroscience ; 30(2): 283-95, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2747918

RESUMO

Electrophysiological characteristics are described for 67 neurones localized to subnuclei of the solitary tract or the area of the dorsal motor nucleus of the vagus in alpha-chloralose-anesthetized, paralysed cats which received vagal and hindlimb sural or peroneal nerve excitation. The peroneal and sural nerves were stimulated in an exposed hindlimb preparation; the ipsilateral vagus was stimulated at the cervical level. Compound action potentials were recorded from all three nerves. Neurons were recorded with extracellular microelectrodes from the brain stem solitary area contralateral to the stimulated somatic nerves. Ninety-one percent of the recorded neurons were spontaneously active. Eighteen percent and 5% of the neurons received only peroneal or sural excitation, respectively, while 59% of the neurons received convergent peroneal and sural excitation. Thirty-nine of the 67 neurons were also tested for vagal input of which 41% responded with excitation. All of the neurons tested for vagal input also received converging excitation from one or both of the somatic nerves. Thirty-one percent of the vagal-excited neurons received converging input from both the peroneal and sural nerves. The combined mean minimal conduction velocity for peroneal and sural input was 31 +/- 1 m/s (mean +/- 1 S.E., range 9-54 m/s). Thirty-six percent of the peroneal and 31% of the sural afferents were Group II fibers. Significant periods of inhibition of spontaneous neuronal spike activity followed peroneal and sural excitation in 43 and 39% of the neurons, respectively. In many neurons, both excitation and inhibition of spike activity could be elicited at stimulus intensities as low as 1.2 times threshold for the lowest threshold fibers in each nerve. Somatic nerve-induced inhibition of spontaneous neuron activity without prior excitation was also observed. These results suggest that neurons of the solitary tract nuclei receive Group II and Group III somatic afferents which converge on neurons also receiving excitatory vagal input. Consequently, somesthetic and kinesthetic as well as visceral receptor activation may directly modulate solitary tract neurons. A possible conclusion is that the nucleus tractus solitarius is the initial central site of mediation of somatosympathetic reflexes. Modulation of the nucleus tractus solitarius by somatic afferents may then adjust sympathetic tone, via modulation of other medullary centers, in visceral and somatic tissues to match somatic metabolic needs.


Assuntos
Bulbo/fisiologia , Neurônios Aferentes/fisiologia , Nervos Periféricos/fisiologia , Nervo Vago/fisiologia , Potenciais de Ação , Animais , Gatos , Membro Posterior/inervação , Condução Nervosa , Nervo Fibular , Tempo de Reação/fisiologia , Nervo Sural
13.
Neuroscience ; 11(2): 497-507, 1984 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-6201783

RESUMO

Efferent connections from a portion of the cerebellar fastigial nucleus were investigated using autoradiography. Bipolar stimulating electrodes were placed in the fastigial nucleus of anesthetized beagles and the area that produced increases in blood pressure and heart rate was localized. A mixture of [3H]leucine and [3H]proline (4:1) was injected into the area and autoradiograms of transported material were prepared. Injections filled the rostral and various parts of the caudal fastigial nucleus. Labeled axons reached the brain stem via two routes, the ipsilateral juxtarestiform body and the contralateral uncinate fasciculus. Ventral portions of the lateral vestibular nucleus were labeled bilaterally, projections to the inferior vestibular and medial vestibular nuclei are contralateral. Nucleus tractus solitarius was heavily labeled on the side opposite the injection. The contralateral medial reticular formation contained many labeled terminals and axons. Label was found in the nucleus reticularis ventralis, lateral reticular nucleus, nucleus gigantocellularis, nucleus pontis caudalis and the paramedian reticular nucleus. No terminal labeling was found in nucleus parvocellularis or nucleus ambiguous. Stimulation of the rostral fastigial nucleus produces increases in blood pressure and heart rate by generalized sympathoexcitation. Many cell groups which facilitate the activity of preganglionic sympathetic neurons do not receive direct fastigial input. It is suggested that that sympathoexcitation resulting from stimulation of the fastigial nucleus occurs through multisynaptic connections in the brain stem.


Assuntos
Sistema Nervoso Autônomo/fisiologia , Pressão Sanguínea , Tronco Encefálico/anatomia & histologia , Núcleos Cerebelares/anatomia & histologia , Frequência Cardíaca , Animais , Transporte Axonal , Tronco Encefálico/fisiologia , Núcleos Cerebelares/fisiologia , Cães , Vias Eferentes/anatomia & histologia , Vias Eferentes/fisiologia , Estimulação Elétrica , Leucina/metabolismo , Prolina/metabolismo
14.
Neuroscience ; 18(1): 105-20, 1986 May.
Artigo em Inglês | MEDLINE | ID: mdl-2426627

RESUMO

Efferent connections to midbrain and thalamus from portions of the cerebellar fastigial nucleus were investigated using autoradiographic techniques. Bipolar stimulating electrodes were placed in the fastigial nucleus of anesthetized beagles and the area which produced maximal increases in blood pressure and heart rate was localized in each dog. A mixture of [3H]leucine and [3H]proline (4:1) was injected into that area and autoradiograms were prepared. Injections filled the rostral and various parts of the caudal fastigial nucleus. The rostral-caudal extent of injection sites were mapped in the horizontal plane from sequential coronal, thionin-stained sections and "primary" and "secondary" injection zones were defined according to specific criteria. Labeled axons reached the mesencephalon via the contralateral uncinate fasiculus. Ascending fibers assembled in a diffuse contingent at the prerubral level adjacent to the ventrolateral periaqueductal gray. The heaviest projections were contralateral to the injection site, but ipsilateral terminals were observed as well. In the midbrain, axons entered the contralateral and ipsilateral superior colliculus to branch repeatedly and terminate in the deep and intermediate layers. Additional terminals were observed bilaterally in the nuclei of the posterior commissure and pretectal areas at the midbrain-diencephalic junction. In the thalamus, labeled axons formed into three groups which terminated in: the contralateral paraventricular complex and medial dorsal nucleus; the contralateral central medial, paracentral, parafasicular and central lateral nuclei, and the contralateral ventral medial and ventral lateral nuclei. There was a sparse projection to the ipsilateral ventral lateral nucleus. The contralateral projection to the ventral medial and ventral lateral nuclei was marked by dense clusters of label ventral to the internal medullary lamina extending, in the dorsal ventral lateral nucleus, to its rostral pole. Projections to specific somesthetic thalamus or the hypothalamus were not observed. These ascending projections in the canine brain generally conform to those described in other nonprimate mammals. The fastigial nucleus presumably provides information concerning equilibrium and body proprioception to the superior colliculus and to thalamic nuclei including both specific motor relay and "nonspecific" midline and intralaminar nuclei, much the same as reported in the cat. The projection to the ventral medial and ventral lateral thalamic nuclei terminate in areas known to participate in the control of axial and proximal limb muscle activity.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Núcleos Cerebelares/anatomia & histologia , Vias Eferentes/anatomia & histologia , Mesencéfalo/anatomia & histologia , Tálamo/anatomia & histologia , Aminoácidos , Animais , Autorradiografia , Transporte Axonal , Cães , Feminino , Trítio
15.
Neuroscience ; 19(4): 1293-301, 1986 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-3822123

RESUMO

Input from the cerebellar fastigial nuclei to neurons at the lateral margin of the nuclei of the solitary tract, particularly to the area identified as the nucleus parasolitarius was investigated in acutely prepared, anesthetized dogs. Fastigial nucleus stimulation led to short latency excitation of nucleus parasolitarius units often followed by prolonged inhibition of spontaneous activity. Excitation from deep skeletal muscle afferents, converged on 25% of the spontaneously active units excited from the fastigial nuclei; these afferents originated primarily from the ipsilateral forelimb muscles. This study provides electrophysiological evidence for fastigial modulation of neurons previously demonstrated autoradiographically to receive presumed monosynaptic fastigial nucleus efferents. The convergence of forelimb muscle afferent information tentatively identified as being from Group Ia or Group II pressure stretch receptors suggests that the nucleus parasolitarius may be an integrative area for cerebellar, sensorimotor and/or autonomic information.


Assuntos
Núcleos Cerebelares/fisiologia , Bulbo/fisiologia , Animais , Mapeamento Encefálico , Cães , Potenciais Evocados , Articulações/inervação , Músculos/inervação , Vias Neurais/fisiologia , Neurônios Aferentes/fisiologia , Pele/inervação , Medula Espinal/fisiologia
16.
Brain Res ; 117(1): 115-24, 1976 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-990926

RESUMO

The cytosol fraction of septum, hypothalamus, and hippocampus of intact and adrenalectomized pigs possessed greater concentrations of radioactivity than the cytosol fraction of amygdala, pituitary, and cortex after an intraventricular injection of [1,2-3H]hydrocortisone. Nuclear extracts from the same brain regions possessed higher concentrations of radioactivity than nuclear extracts of the other brain regions of intact pigs. Nuclear extracts of amygdala, pituitary and hypothalamus from adrenalectomized pigs exhibited the greatest increase over intact pigs in labeled hormone concentration. When adrenalectomized pigs were administered dexamethasone prior to [3H]hydrocortisone, uptake of label was most depressed in hippocampal cytosol and cuclear extract. Also sensitive to the competitive effects of dexamethasone were septal and pituitary nuclear extracts. In intact pigs, pituitary, hippocampus and cortex exhibited higher ratios of bound to total hormone in the cytososl fraction than the other brain regions. Hippocampal and amygdala cytosol possessed the greater magnitude of increase in the ratio of bound to total hormone in adrenalectomized versus intact pigs. The pituitary, septum, amygdala, and cortex of intact and adrenalectomized pigs possessed a ratio of bound to total hormone in nuclear extract 5-10 times greater than that in hippocampus and hypothalamus. However, the latter two regions exhibited a greater increase in bound: total hormone after administration of labeled hormone to adrenalectomized pigs than nuclear extracts of the other brain regions.


Assuntos
Encéfalo/metabolismo , Hidrocortisona/metabolismo , Glândulas Suprarrenais/metabolismo , Tonsila do Cerebelo/metabolismo , Animais , Córtex Cerebral/metabolismo , Citosol/metabolismo , Dexametasona/metabolismo , Hipocampo/metabolismo , Hipotálamo/metabolismo , Hipófise/metabolismo , Septo Pelúcido/metabolismo , Suínos
17.
Free Radic Res ; 28(2): 125-9, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9645389

RESUMO

Activities of three types of superoxide dismutase in tissue fractions were significantly lower in fetal and adult brain and fetal limb preparations than in fetal and adult heart preparations. An exception was the cytoplasmic fraction of adult brain that had levels of Cu, Zn-superoxide dismutase activity comparable to those in cytoplasmic fractions of heart. In addition, Mn superoxide dismutase activity appeared to be very low in all fetal mitochondrial matrix fractions and cytoplasmic fractions as well as in adult brain. Finally, the results of these studies emphasize the importance of two antioxidant defense systems in the tissues studied, one associated with the mitochondrial electron transport system and the other, the cytosolic Cu, Zn enzyme.


Assuntos
Proteínas Fetais/análise , Superóxido Dismutase/análise , Animais , Encéfalo/embriologia , Encéfalo/enzimologia , Cátions Bivalentes/análise , Extremidades/embriologia , Coração Fetal/enzimologia , Isoenzimas/análise , Mitocôndrias/enzimologia , Proteínas Musculares/análise , Miocárdio/enzimologia , Proteínas do Tecido Nervoso/análise , Especificidade de Órgãos , Ratos , Ratos Sprague-Dawley
18.
Brain Res Bull ; 4(5): 669-74, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-487223

RESUMO

The effects on spontaneous and ionophore-induced transmitter release of the inorganic dye, ruthenium red (RuR), a known inhibitor of calcium binding sites, were observed at the frog sartorius neuromuscular junction using intracellular recording techniques. Both crude and purified RuR, at concentrations of 1 and 5 micron depressed or blocked spontaneous release of acetylcholine (ACh) and reduced postsynaptic sensitivity to ACh, the crude dye being more potent than the pure. Pretreatment of muscles with RuR prevented the catastrophic reaction of junctions to 100 micron X537A ionophore. Increased levels of Ca2+ restored spontaneous transmitter release to control levels after depression or blockade by RuR. It was concluded that RuR blocks a critical membrane-bound binding site for calcium which is necessary for quantal release of transmitter.


Assuntos
Acetilcolina/metabolismo , Lasalocida/farmacologia , Junção Neuromuscular/efeitos dos fármacos , Rutênio Vermelho/farmacologia , Rutênio/farmacologia , Animais , Anuros , Cálcio/farmacologia , Potenciais Evocados/efeitos dos fármacos
19.
J Electromyogr Kinesiol ; 2(1): 1-9, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-20870521

RESUMO

The firing of 97 soleus motor units (MUs) and 52 triceps brachii MUs of eight volunteers has been studied in the tonic vibration reflex. The vibration frequency was varied from 30 to 150 Hz. Interspike interval histograms of single MUs as well as cross-correlograms between their spikes and vibration mechanograms were obtained to reveal the correlation between MU discharges and vibration stimuli. In all of the MUs studied, both methods revealed the correlation. More detailed study of the discharge pattern of soleus MUs revealed the dependence of the correlation on the vibration frequency: the highest degree of correlation was observed at low vibration frequencies (30-50 Hz); the correlation gradually decreased with the increase in vibration frequency and disappeared with frequencies higher than 85 Hz. However, the correlation was observed when high frequency vibration was applied to a voluntarily contracted muscle. The muscle contraction also removed the vibration-induced depression of the soleus H reflex. At low frequency vibration, the correlation may be caused by the group II afferent EPSPs. A voluntary muscle contraction seems to be accompanied by removal of the vibration-induced presynaptic inhibition of the monosynaptic input to motoneurons from Ia afferents that leads to the correlation at high vibration frequencies.

20.
J Electromyogr Kinesiol ; 6(3): 169-75, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20719674

RESUMO

Discharges of single motor units (MUs) in human triceps brachii and deltoid muscle were recorded using needle electromyography during after-contraction and voluntary contraction performed either against a small elastic load or under isometry. The steady-state firing rate of the MUs was lower under after-contraction than during voluntary movement of comparable amplitude and time course (or isometric force level), whereas variability of interspike intervals was similar under the two conditions. In the tibialis anterior muscle (where after-contraction was lacking), a weak voluntary contraction preceded by sustained strong voluntary effort also showed lower firing rate of MUs as compared to similar voluntary movement performed after a rest period. We concluded that sustained contraction gave rise to peripheral potentiation of contractile properties of the muscle, irrespective of whether it was proximal or distal, whereas after-contraction was due to a central tonic drive that differed for proximal and distal muscles.

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