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1.
J Cell Biol ; 150(1): 253-64, 2000 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-10893272

RESUMO

Embryos homozygous for mutations in the unc-52, pat-2, pat-3, and unc-112 genes of C. elegans exhibit a similar Pat phenotype. Myosin and actin are not organized into sarcomeres in the body wall muscle cells of these mutants, and dense body and M-line components fail to assemble. The unc-52 (perlecan), pat-2 (alpha-integrin), and pat-3 (beta-integrin) genes encode ECM or transmembrane proteins found at the cell-matrix adhesion sites of both dense bodies and M-lines. This study describes the identification of the unc-112 gene product, a novel, membrane-associated, intracellular protein that colocalizes with integrin at cell-matrix adhesion complexes. The 720-amino acid UNC-112 protein is homologous to Mig-2, a human protein of unknown function. These two proteins share a region of homology with talin and members of the FERM superfamily of proteins. We have determined that a functional UNC-112::GFP fusion protein colocalizes with PAT-3/beta-integrin in both adult and embryonic body wall muscle. We also have determined that UNC-112 is required to organize PAT-3/beta-integrin after it is integrated into the basal cell membrane, but is not required to organize UNC-52/perlecan in the basement membrane, nor for DEB-1/vinculin to localize with PAT-3/beta-integrin. Furthermore, UNC-112 requires the presence of UNC-52/perlecan and PAT-3/beta-integrin, but not DEB-1/vinculin to become localized to the muscle cell membrane.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Moléculas de Adesão Celular/genética , Matriz Extracelular/metabolismo , Integrinas/metabolismo , Proteínas de Membrana , Músculos/metabolismo , Animais , Caenorhabditis elegans/metabolismo , Moléculas de Adesão Celular/metabolismo , Membrana Celular/metabolismo , Proteínas de Fluorescência Verde , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Integrinas/genética , Proteínas Luminescentes/genética , Dados de Sequência Molecular , Músculos/citologia , Proteoglicanas/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Homologia de Sequência de Aminoácidos
2.
J Cell Biol ; 123(4): 949-62, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8227151

RESUMO

To identify and localize the protein products of genes encoding distinct L-type calcium channels in central neurons, anti-peptide antibodies specific for the class C and class D alpha 1 subunits were produced. Anti-CNC1 directed against class C immunoprecipitated 75% of the L-type channels solubilized from rat cerebral cortex and hippocampus. Anti-CND1 directed against class D immunoprecipitated only 20% of the L-type calcium channels. Immunoblotting revealed two size forms of the class C L-type alpha 1 subunit, LC1 and LC2, and two size forms of the class D L-type alpha 1 subunit, LD1 and LD2. The larger isoforms had apparent molecular masses of approximately 200-210 kD while the smaller isoforms were 180-190 kD, as estimated from electrophoresis in gels polymerized from 5% acrylamide. Immunocytochemical studies using CNC1 and CND1 antibodies revealed that the alpha 1 subunits of both L-type calcium channel subtypes are localized mainly in neuronal cell bodies and proximal dendrites. Relatively dense labeling was observed at the base of major dendrites in many neurons. Staining in more distal dendritic regions was faint or undetectable with CND1, while a more significant level of staining of distal dendrites was observed with CNC1, particularly in the dentate gyrus and the CA2 and CA3 areas of the hippocampus. Class C calcium channels were concentrated in clusters, while class D calcium channels were generally distributed in the cell surface membrane of cell bodies and proximal dendrites. Our results demonstrate multiple size forms and differential localization of two subtypes of L-type calcium channels in the cell bodies and proximal dendrites of central neurons. The differential localization and multiple size forms may allow these two channel subtypes to participate in distinct aspects of electrical signal integration and intracellular calcium signaling in neuronal cell bodies. The preferential localization of these calcium channels in cell bodies and proximal dendrites implies their involvement in regulation of calcium-dependent functions occurring in those cellular compartments such as protein phosphorylation, enzyme activity, and gene expression.


Assuntos
Canais de Cálcio/análise , Neurônios/química , Sequência de Aminoácidos , Animais , Encéfalo/ultraestrutura , Química Encefálica , Canais de Cálcio/classificação , Dendritos/química , Imuno-Histoquímica , Dados de Sequência Molecular , Testes de Precipitina , Ratos
3.
Graefes Arch Clin Exp Ophthalmol ; 231(8): 433-8, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8224940

RESUMO

Despite surgical reattachment of the retina in infants with severe retinopathy of prematurity (ROP), visual acuity may decline. We performed gonioscopy and applanation tonometry on 26 eyes of 17 infants with severe ROP who were randomly selected and followed prospectively for 2 years. Of these 26 eyes, one eye of one patient had only peripheral retinocryopexy for threshold stage III disease and had an attached retina before enrollment into the study. Sixteen infants subsequently underwent vitrectomy, scleral buckle, or both. Retinal reattachment of the posterior pole was present in at least one eye each of 10 of the 17 infants. Glaucoma was diagnosed in 5 of the 10 patients; all 5 showed a decrease in visual acuity of greater than 1 octave. Of the 5 infants without glaucoma, 3 showed visual improvement, and 2 remained the same. Although we studied a small number of cases, our results suggest that glaucoma may be a cause of visual decline in infants with severe ROP. A decline in visual acuity in infants with severe ROP and surgical retinal reattachment may warn us of glaucoma, as this diagnosis is difficult to make in these small infants.


Assuntos
Glaucoma/complicações , Retinopatia da Prematuridade/complicações , Transtornos da Visão/etiologia , Pré-Escolar , Feminino , Seguimentos , Glaucoma/diagnóstico , Gonioscopia , Humanos , Incidência , Lactente , Recém-Nascido , Pressão Intraocular , Masculino , Estudos Prospectivos , Distribuição Aleatória , Descolamento Retiniano/cirurgia , Retinopatia da Prematuridade/diagnóstico , Retinopatia da Prematuridade/cirurgia , Tonometria Ocular , Transtornos da Visão/diagnóstico , Acuidade Visual , Vitrectomia
4.
J Pediatr Gastroenterol Nutr ; 15(3): 253-9, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1432462

RESUMO

Previous studies have shown that there is minimal fecal excretion of carbohydrate energy in premature infants with high breath H2 concentrations, implying that the colon plays an important role in salvaging lactose energy. The present study extends this work by using a stable isotope method for serial assessment of lactose carbon excretion. Thus, in nine premature infants (30-32 weeks of gestation and 11-36 days of age), we conducted 23 longitudinal studies of breath hydrogen concentration and the cumulative fecal excretion of 13C derived from a single dose of [D-1-13C]lactose. The ranges of values (mean +/- SD) for breath hydrogen concentration and lactose absorption were respectively 4-440 ppm/5% CO2 (92 +/- 100) and 82-100% tracer dose (98.4 +/- 3.9). In 21 studies, lactose carbon excretion was less than 2% of the dose. There was a significant correlation between postnatal age and breath hydrogen concentration (R = 0.48; p = 0.02). These studies suggest that colonic fermentation activity is adequate for efficient colonic salvage of lactose even during the second week of life.


Assuntos
Carbono/farmacocinética , Recém-Nascido Prematuro/metabolismo , Lactose/farmacocinética , Testes Respiratórios , Isótopos de Carbono , Metabolismo Energético , Fezes/química , Humanos , Hidrogênio/análise , Lactente , Recém-Nascido
5.
Rev. Assoc. Med. Bras. (1992, Impr.) ; 38(3): 174-176, Jul.-Set. 1992.
Artigo em Português | LILACS | ID: lil-320055

RESUMO

Case report of a 24 year old female patient with ALL that developed pulmonary invasive aspergillosis during aplastic phase of induction chemotherapy. She was treated with antibiotics and amphotericin B. After recovering from neutropenia, she developed a mycetoma in the inferior lobe of the right lung, which required lobectomy. Nine months after surgery the patient is well, in complete remission of ALL and with no evidence of infection. One month after lobectomy, chemotherapy had been reintroduced. Attention should be called to this form of therapy of Aspergillosis, as a successful way to eradicate this fungal infection that responds poorly to antifungal drugs currently used.


Assuntos
Humanos , Feminino , Adulto , Aspergilose , Neutropenia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Pneumopatias Fúngicas/cirurgia , Aspergilose , Pneumopatias Fúngicas/etiologia
6.
Rev Assoc Med Bras (1992) ; 38(3): 174-6, 1992.
Artigo em Português | MEDLINE | ID: mdl-1340369

RESUMO

Case report of a 24 year old female patient with ALL that developed pulmonary invasive aspergillosis during aplastic phase of induction chemotherapy. She was treated with antibiotics and amphotericin B. After recovering from neutropenia, she developed a mycetoma in the inferior lobe of the right lung, which required lobectomy. Nine months after surgery the patient is well, in complete remission of ALL and with no evidence of infection. One month after lobectomy, chemotherapy had been reintroduced. Attention should be called to this form of therapy of Aspergillosis, as a successful way to eradicate this fungal infection that responds poorly to antifungal drugs currently used.


Assuntos
Aspergilose/cirurgia , Pneumopatias Fúngicas/cirurgia , Neutropenia/complicações , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Adulto , Aspergilose/etiologia , Feminino , Humanos , Pneumopatias Fúngicas/etiologia
7.
Graefes Arch Clin Exp Ophthalmol ; 230(5): 406-10, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1521803

RESUMO

We determined intraocular pressure (IOP) in 55 premature infants (122 determinations) with stage V retinopathy of prematurity (ROP) by applanation and indentation tonometry corrected for scleral rigidity and found a modest correlation of r = 0.52 between readings. Chronologic age and the scleral rigidity coefficient were the most significant factors affecting the closeness in readings. Our findings suggest that the applanation method of obtaining IOP values is preferable in infants with ROP because this method is less affected by technical error and the variable nature of premature infant sclera. Frequent examination may be necessary to detect an early IOP increase, especially in infants who have had successful retinal reattachment through vitreoretinal techniques.


Assuntos
Pressão Intraocular , Retinopatia da Prematuridade/fisiopatologia , Tonometria Ocular/métodos , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino
8.
Neuron ; 7(1): 45-57, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1648941

RESUMO

A number of pharmacologically and electrophysiologically distinct voltage-dependent Ca2+ channels have been identified in mammalian neurons. Two rat brain Ca2+ channel alpha 1 subunits (rbC-I and rbC-II) have been isolated by molecular cloning and shown to be highly related (95%) to the cardiac dihydropyridine-sensitive Ca2+ channel. The rbC-II protein is distinct from rbC-I in that it contains a 3 amino acid insert in the putative cytoplasmic loop between domains II and III and a 28 amino acid substitution corresponding to the third transmembrane segment (S3) of the fourth domain. We show that rbC-I and rbC-II transcripts are generated by alternative splicing and that they are differentially expressed in the rat CNS.


Assuntos
Encéfalo/metabolismo , Canais de Cálcio/genética , DNA Recombinante , Splicing de RNA , Sequência de Aminoácidos , Animais , Canais de Cálcio/metabolismo , Genes , Dados de Sequência Molecular , Oócitos/metabolismo , Ratos , Transcrição Gênica , Xenopus
9.
Proc Natl Acad Sci U S A ; 87(9): 3391-5, 1990 May.
Artigo em Inglês | MEDLINE | ID: mdl-1692134

RESUMO

We describe the isolation and characterization of several rat brain cDNAs that are homologous to the alpha 1 subunit of heart and skeletal muscle dihydropyridine-sensitive Ca channels. Northern blot analysis of 32 cDNAs shows that they can be grouped into four distinct classes (A, B, C, and D), each corresponding to a distinct hybridization pattern of brain mRNAs. Southern blot and DNA sequencing suggest that each class of cDNA represents a distinct gene or gene family. In the regions sequenced, the rat brain class C and D gene products share approximately 75% amino acid identity with the rabbit skeletal muscle Ca channel. In addition, the class C polypeptide is almost identical to the rabbit cardiac Ca channel (97% identity). In contrast, the rat brain class A and B cDNAs are more distantly related to dihydropyridine-sensitive Ca channels (47-64% amino acid identity) and to the brain class C and D genes (51-55% amino acid identity). To examine the functional significance of the isolated brain cDNAs, hybrid depletion experiments were performed in Xenopus oocytes. Antisense oligonucleotides against class A and B cDNAs each partially inhibited, and a class C oligonucleotide almost fully inhibited, the expression of Ba current in rat brain mRNA injected oocytes; but none of the oligonucleotides affected the expression of voltage-gated Na or K conductances. The clone characterization and sequencing results demonstrate that a number of distinct, yet related, voltage-gated Ca-channel genes are expressed in the brain. The antisense oligonucleotide experiments specifically show that one or several of the Ca-channel classes are related to the Ca channels observed in rat brain mRNA injected oocytes.


Assuntos
Encéfalo/metabolismo , Canais de Cálcio/metabolismo , Proteínas de Membrana/genética , Família Multigênica , Sequência de Aminoácidos , Animais , Clonagem Molecular , DNA/genética , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Sondas de Oligonucleotídeos , RNA/genética , RNA/isolamento & purificação , Ratos , Homologia de Sequência do Ácido Nucleico
10.
Ophthalmology ; 97(1): 122-30, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2314833

RESUMO

To understand the mechanisms of glaucoma in retinopathy of prematurity (ROP), anterior segment evaluation is essential. The authors prospectively examined the anterior segment of 27 eyes of 17 premature infants with stages IV and V ROP. Twenty-six eyes received no previous surgery or treatment. Schiøtz and applanation tonometry were performed. Structural evaluation of each anterior segment was conducted by biomicroscopy and Koeppe gonioscopy. In the 26 eyes, angle closure of greater than 180 degrees was noted in 3 (12%). The authors noted prominent Schwalbe's line in 4 eyes (15%), high iris convexity in 15 (58%), hypopigmentation of the iris root in 19 (73%), translucent matrix in the angles ("Barkan's-type" membrane) in 18 (69%), posterior synechiae in 16 (62%), visible iris or angle vessels in 12 (46%), and pigment clumping in the angle recess in 12 (46%). This study identified structural abnormalities in the anterior segment of ROP infants, including pathologic changes and anatomic features that could have a developmental origin.


Assuntos
Segmento Anterior do Olho/patologia , Retinopatia da Prematuridade/patologia , Pré-Escolar , Feminino , Seguimentos , Idade Gestacional , Glaucoma/etiologia , Gonioscopia , Humanos , Lactente , Recém-Nascido , Pressão Intraocular , Iris/patologia , Masculino , Estudos Prospectivos , Retinopatia da Prematuridade/complicações , Tonometria Ocular
11.
J Toxicol Environ Health ; 12(4-6): 767-73, 1983.
Artigo em Inglês | MEDLINE | ID: mdl-6668622

RESUMO

The cytogenetic effects of methylmercury (MeHg) producing chromosomal breakages, C-mitosis, and sister chromatid exchange are well documented. The present investigation was to determine whether vitamin E, which has been shown to exert a certain protective measure on the nervous system of animals exposed to methylmercury, also will diminish the genotoxicity of MeHg. Adult hamsters were given a daily injection (ip) of methylmercury chloride at a dosage of 2.0 mg/kg body weight (kg b.w.) and/or with 2.0 mg/kg b.w. vitamin E for 3 wk. All animals were sacrificed 5 d after the last day of MeHg exposure. Fibroblast cultures were established with cells obtained from skins of these animals. Chromosome preparations were made from these cultures and evaluated, using a double-blind system, for incidences of chromosomal breakage. It was found that all the fibroblast cultures grew well except from those animals treated with MeHg. Furthermore, while the saline control and vitamin E alone cultures showed no significant number of chromosomal breakages, cells from animals treated with only MeHg showed a high incidence of chromosomal damage (50% with 1 break and 15% with 2 or more breaks). Such chromosomal damage, however, was totally eliminated by vitamin E treatment (no chromosomal breakage was observed in cultures from MeHg/vitamin E animals). Our present study represents the first report on in vitro chromosomal damages as a result of in vivo MeHg exposure. Furthermore, our investigation also demonstrated the protective potential of vitamin E against genotoxicity of methylmercury.


Assuntos
Aberrações Cromossômicas , Compostos de Metilmercúrio/toxicidade , Vitamina E/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Cricetinae , Radicais Livres , Masculino , Mesocricetus , Compostos de Metilmercúrio/metabolismo
12.
Appl Opt ; 19(12): 1930-6, 1980 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-20221157

RESUMO

The Shroud of Turin is a partially scorched linen cloth containing an apparently bloodstained sepia image of a man lying in a state of repose. It is believed by some to be the burial cloth of Jesus of Nazareth. A team of scientists, under the auspices of The Shroud of Turin Research Project, Inc., performed nondestructive measurements on the Shroud with electromagnetic energy from x ray to the IR to develop data leading to the analysis of the substances making up the body image stains and bloodstains. Presented here are UV-visible reflectance and fluoroescence spectra of the sepia body image area and scorched and bloodstained areas on the shroud.

13.
J Int Med Res ; 6(1): 14-23, 1978.
Artigo em Inglês | MEDLINE | ID: mdl-342300

RESUMO

Butorphanol tartrate (4 mg and 8 mg) was compared to codeine phosphate (60 mg) and placebo for oral analgesic activity and side-effects employing a double-blind design in ninety-three out-patients suffering from moderate to very severe musculoskeletal pain. The study duration was 72 hours with medication administered every 4 to 6 hours (four times daily) for a total of twelve doses per patient. The results demonstrate that both the 4 mg and 8 mg doses of butorphanol were significantly better (p less than 0.u5) than placebo. While codeine 60 mg also proved active, it appears to be less efficacious than the high dose of butorphanol. The peak effect appeared to be evident in 1 to 2 hours. Butorphanol may be at least seven times more potent than codeine on a milligram basis. Although no serious side-effects were observed, butorphanol appeared to present a greater incidence of side-effects than codeine and placebo in this study.


Assuntos
Analgésicos/uso terapêutico , Codeína/uso terapêutico , Morfinanos/uso terapêutico , Dor/tratamento farmacológico , Adolescente , Adulto , Idoso , Doenças Ósseas/tratamento farmacológico , Ensaios Clínicos como Assunto , Codeína/efeitos adversos , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Morfinanos/efeitos adversos , Doenças Musculares/tratamento farmacológico , Placebos
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