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1.
OTJR (Thorofare N J) ; 41(2): 80-89, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33393417

RESUMO

As chronic pain (CP) interferes with an individual's lifestyle by limiting meaningful activities and health-related quality of life (HRQoL), occupational therapy (OT) plays an important role in CP management interventions. This pilot study aimed to explore the influence of a 13-week French-Canadian Lifestyle Redesign® for CP. A mixed-methods research design including a preexperimental quantitative component pre-/posttest was used with 15 participants with fibromyalgia. Although pain remained unchanged after the intervention, improvements were observed in participants' engagement in meaningful activities (p < .01), life balance (p < .01), mental components of HRQoL (p < .01), depressive symptoms (p = .047), and pain self-efficacy (p < .01). After the intervention, phone interviews (n = 6) highlighted the participants' appreciation of the focus being placed on their daily routines and the development of a sense of belonging throughout the intervention. This study suggests the potential feasibility and benefits of an occupation-based approach in CP management.


Assuntos
Manejo da Dor , Qualidade de Vida , Canadá , Humanos , Estilo de Vida , Projetos Piloto
3.
Wound Repair Regen ; 15(3): 332-40, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17537120

RESUMO

The diagnosis of burn depth is based on a visual assessment and can be subjective. Near-infrared (NIR) spectroscopic devices were used preclinically with positive results. The purpose of this study was to test the devices in a clinical setting using easily identifiable burn wounds. Adult patients with acute superficial and full-thickness burns were enrolled. NIR point spectroscopy and imaging devices were used to collect hemodynamic data from the burn site and an adjacent unburned control site. Oxy-hemoglobin and deoxy-hemoglobin concentrations were extracted from spectroscopic data and reported as oxygen saturation and total hemoglobin. Sixteen patients (n=16) were included in the study with equal numbers in both burn wound groups. Point spectroscopy data showed an increase in oxygen saturation (p<0.0095) and total hemoglobin (<0.0001) in comparison with the respective control areas for superficial burn wounds. The opposite was true for full-thickness burns, which showed a decrease in oxygenation (p<0.0001) and total hemoglobin (p<0.0147) in comparison with control areas. NIR imaging technology provides an estimate of hemodynamic parameters and could easily distinguish superficial and full-thickness burn wounds. These results confirm that NIR devices can successfully distinguish superficial and full-thickness burn injuries.


Assuntos
Queimaduras/patologia , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Distribuição de Qui-Quadrado , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oxiemoglobinas/análise
4.
Mult Scler ; 13(2): 220-3, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17439888

RESUMO

We used a global positioning satellite technology odometer to determine the maximum objective walking distance capacity (MOWD) of patients with multiple sclerosis (MS). The MOWD correlated with Expanded Disability Status Scale (EDSS) score (r(2) =0.41; P <0.0001), the MSWS-12 scale (r(2) =0.46; P <0.0001), time to walk 10 m (r(2) =0.51; P <0.02) and walking speed (r(2) =0.75; P <0.001). Limitation of walking capacities was measurable up to 4550 m, strikingly above the 500-m limit of the EDSS. This objective odometer is a promising tool for evaluation and follow-up of patients with MS.


Assuntos
Avaliação da Deficiência , Esclerose Múltipla Crônica Progressiva/fisiopatologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Índice de Gravidade de Doença , Telemetria/instrumentação , Caminhada , Adulto , Feminino , Seguimentos , Sistemas de Informação Geográfica , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Comunicações Via Satélite , Telemetria/normas
5.
Science ; 315(5812): 612-7, 2007 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-17272712

RESUMO

Since the mid-1980s, our understanding of nutrient limitation of oceanic primary production has radically changed. Mesoscale iron addition experiments (FeAXs) have unequivocally shown that iron supply limits production in one-third of the world ocean, where surface macronutrient concentrations are perennially high. The findings of these 12 FeAXs also reveal that iron supply exerts controls on the dynamics of plankton blooms, which in turn affect the biogeochemical cycles of carbon, nitrogen, silicon, and sulfur and ultimately influence the Earth climate system. However, extrapolation of the key results of FeAXs to regional and seasonal scales in some cases is limited because of differing modes of iron supply in FeAXs and in the modern and paleo-oceans. New research directions include quantification of the coupling of oceanic iron and carbon biogeochemistry.


Assuntos
Ecossistema , Ferro , Fitoplâncton/crescimento & desenvolvimento , Água do Mar , Zooplâncton/crescimento & desenvolvimento , Animais , Atmosfera , Carbono/análise , Carbono/metabolismo , Dióxido de Carbono , Clorofila/análise , Clima , Diatomáceas/crescimento & desenvolvimento , Ferro/análise , Oceanos e Mares , Fitoplâncton/metabolismo
6.
Rev Neurol (Paris) ; 162(8-9): 827-31, 2006 Sep.
Artigo em Francês | MEDLINE | ID: mdl-17028543

RESUMO

INTRODUCTION: CADASIL is a hereditary cerebral arteriopathy leading to progressive disability and dementia usually observed at 60 years. OBSERVATION: We report four patients aged>60 years with typical Notch3 mutations leading to CADASIL who did not have dementia or disability. Three of them presented with only transient neurological manifestations. MRI results showed extensive hyperintense signals in the white-matter on T2-weighted images contrasting with very few lacunar infarcts. CONCLUSION: These observations suggest that silent or symptomatic infarcts, which were rare in the present cases may be responsible for the clinical severity in this disorder.


Assuntos
CADASIL/fisiopatologia , Idoso , CADASIL/psicologia , Transtornos Cognitivos/etiologia , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
7.
Encephale ; 29(3 Pt 1): 239-47, 2003.
Artigo em Francês | MEDLINE | ID: mdl-12876548

RESUMO

Precise diagnosis of eating disorders has long been problematic. First off, although the DSM IV provides clear criteria, these are applicable to a very narrow range of disorders. Subclinical disorders, although well defined in the literature, are difficult to diagnose as no tool has been previously available. These subclinical disorders are particularly important if one considers that they are often precursors to more serious and life-threatening eating disorders. In addition, choice of diagnostic tool for eating disorders has also long been the cause of difficulty for both researchers and clinicians. Although interviews are favored for their in-depth approach, they are sometimes difficult to implement and often too long and costly to use on a regular basis. Most available questionnaires are limited by their approach to one or two diagnostic categories, and again, until now, no tool has fully addressed the issue of subclinical disorders. The goal of this work was to translate and use a new questionnaire, The Questionnaire for Eating Disorders (Q-EDD), which was developed in the United States and based on both DSM IV criteria as well as carefully developed subclinical disorder criteria. The Q-EDD can identify the major eating disorder categories while at the same time distinguishing between different qualities in each (for example restricting versus compensatory anorexia). Moreover, the Q-EDD can identify several subclinical disorder categories, providing useful insight into potentially dangerous evolution of these disorders. In collaboration with one of the original authors, the questionnaire was translated into French with careful attention to DSM IV criteria in order to preserve its original validity. The questionnaire was read by several professionals in psychology as well as lay people to assure its face validity and ease of use. Once the questionnaire was adequately translated and corrected, it was used for an epidemiological study with a large sample of adolescents and young adults (n=1 001) from several Junior High and High Schools in the greater metropolitan area of Toulouse, France. The schools were located in a variety of neighborhoods and represented a wide range of population, some of them being more academic oriented, others being more oriented towards practical training. The population was composed of 703 females and 298 males, with an average age of 17.06 years. In addition, the population included several different ethnic categories, all of which are similarly represented in the general French population. The results from the Q-EDD showed levels of various clinical disorders to replicate data from previous epidemiological studies with 1.5% of the population suffering from a serious clinical DSM IV disorder; 7.9% suffering from DSM IV disorders NOS; and 20.9% suffering subclinical disorders. In addition to this finding of 30% of the population with an eating disorder, it was noted that a large number of these young people fell into the severe underweight and low weight categories. Indeed, nearly 10% of this group were within the weight criteria for anorexia, despite the fact that they did not meet the other criteria. This finding seemed to warrant additional investigation, and as a result, a different cut-off for severe underweight was established using literature references; this cut-off was set at the 10(th) percentile for BMI based on age. Yet, even with this new cut-off, 6% of this population still met a severe underweight criteria suggestive of anorexic pathology. These results led to the formulation of 2 hypotheses to explain this finding, the first of which examines morphological differences, the second of which suggests cultural differences in terms of eating habits and diet. The French version of the Q-EDD appears to follow the psychometric properties of the original version, moreover it provides useful and rich data regarding eating disorders in a format that is simple and efficient.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos/diagnóstico , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Inquéritos e Questionários , Adolescente , Comportamento do Adolescente/psicologia , Adulto , Índice de Massa Corporal , Criança , Diagnóstico Diferencial , Manual Diagnóstico e Estatístico de Transtornos Mentais , Estudos de Viabilidade , Transtornos da Alimentação e da Ingestão de Alimentos/classificação , Feminino , Humanos , Masculino , Psicologia do Adolescente
8.
Toxicon ; 40(10): 1451-62, 2002 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-12368115

RESUMO

We determined the seasonal distribution of paralytic shellfish toxins (PSTs) and PST producing bacteria in > 15, 5-15, and 0.22-5 microm size fractions in the St Lawrence. We also measured PSTs in a local population of Mytilus edulis. PST concentrations were determined in each size fraction and in laboratory incubations of sub-samples by high performance liquid chromatography (HPLC), including the rigorous elimination of suspected toxin 'imposter' peaks. Mussel toxin levels were determined by mouse bioassay and HPLC. PSTs were detected in all size fractions during the summer sampling season, with 47% of the water column toxin levels associated with particles smaller than Alexandrium tamarense (< 15 microm). Even in the > 15 microm size fraction, we estimated that as much as 92% of PSTs could be associated with particles other than A. tamarense. Our results stress the importance of taking into account the potential presence of PSTs in size fractions other than that containing the known algal producer when attempting to model shellfish intoxication, especially during years of low cell abundance. Finally, our HPLC results confirmed the presence of bacteria capable of autonomous PST production in the St Lawrence as well as demonstrating their regular presence and apparent diversity in the plankton.


Assuntos
Toxinas Bacterianas/metabolismo , Bivalves/química , Fracionamento Químico/métodos , Saxitoxina/isolamento & purificação , Estações do Ano , Intoxicação por Frutos do Mar , Animais , Bioensaio , Bivalves/microbiologia , Cromatografia Líquida de Alta Pressão , Camundongos , Paralisia/induzido quimicamente , Paralisia/fisiopatologia , Tamanho da Partícula , Quebeque , Saxitoxina/análogos & derivados , Água do Mar , Frutos do Mar/microbiologia
11.
Neurology ; 55(7): 1052-4, 2000 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-11061271

RESUMO

Using quantitative PET, the authors studied the binding of [11C]PK11195, a marker of activated microglia, in the thalamus of patients with chronic middle cerebral artery infarcts. All patients showed increased [11C]PK11195 binding in the ipsilateral thalamus, indicating the activation of microglia in degenerating projection areas remote from the primary lesion. A persistent increase in [11C]PK11195 binding suggests active, long-term thalamic microstructural changes after corticothalamic connection damage.


Assuntos
Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/patologia , Radioisótopos de Carbono , Isoquinolinas , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Núcleos Talâmicos/diagnóstico por imagem , Núcleos Talâmicos/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada de Emissão
12.
J Cell Sci ; 113 Pt 19: 3453-62, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10984436

RESUMO

Sperm-triggered Ca(2+) oscillations occur throughout the animal kingdom. The mechanism sperm use to trigger Ca(2+) oscillations at fertilization has not been resolved in any egg. The temporal, spatial and regulatory characteristics of the Ca(2+) oscillations during fertilization in ascidians offer a unique advantage over other systems for determining the mechanism of fertilization. For example, sperm trigger two phases of Ca(2+) oscillations that are all waves in ascidians. The first of these Ca(2+) waves begins at the point of sperm-egg fusion while a second phase of Ca(2+) waves originates at a vegetal protrusion termed the contraction pole. In addition, cyclin B1-dependent kinase activity provides a form of positive feedback, maintaining the second phase of Ca(2+) waves during meiosis and thereby ensuring meiotic exit. We therefore prepared cytosolic ascidian sperm extracts or MonoQ-fractionated ascidian sperm extracts from this urochordate to investigate if a Ca(2+)-releasing sperm-borne factor was responsible for egg activation. Spatially, ascidian sperm extract induced repetitive Ca(2+) waves that mimicked the spatial pattern displayed during fertilization: all the second-phase Ca(2+) waves originated at a vegetal protrusion termed the contraction pole (thus mimicking fertilisation). We also demonstrated that ascidian sperm extract-induced Ca(2+) oscillations were maintained when CDK activity was elevated and MAP kinase activity was low, as found previously for sperm-triggered Ca(2+) oscillations. As would be predicted, large doses of ascidian sperm extract injected into prophase-stage oocytes, lacking CDK activity, failed to induce any Ca(2+) release even though they responded to microinjection of the Ca(2+)-releasing second messenger inositol 1,4,5-trisphosphate. Finally, since the Ca(2+)-releasing activity from Mono-Q fractionated ascidian sperm extract eluted predominantly as one fraction, this may imply that one factor is responsible for the Ca(2+)-releasing activity. These data support a model of egg activation whereby the sperm introduces a Ca(2+)-releasing cytosolic factor into the egg. We demonstrated that ascidian sperm contain a protein factor(s) that is regulated by the egg CDK activity and can trigger all the Ca(2+ )waves observed at fertilization with a spatial pattern that mimics those initiated by sperm.


Assuntos
Sinalização do Cálcio , Fertilização , Óvulo/metabolismo , Espermatozoides/química , Urocordados/fisiologia , Animais , Ciclo Celular , Cromatografia , Ciclina B1 , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Feminino , Corantes Fluorescentes/metabolismo , Fura-2/metabolismo , Masculino , Meiose , Microinjeções , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Óvulo/química , Proteínas Recombinantes de Fusão/metabolismo
13.
Can J Microbiol ; 46(7): 623-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10932356

RESUMO

The seasonal development of bacterial abundance in first year bottom ice and underlying seawater were studied at Saroma-ko Lagoon in Hokkaido, Japan, and at Resolute Passage in the High Canadian Arctic during the algal bloom in spring 1992. The aim of this study was to evaluate whether the high algal concentrations reached during the bloom of ice algae have inhibitory effects on bacterial dynamics. Bacterial abundance (measured as total cell count and colony-forming units CFU) increased with the increase of the algal biomass up to 500 micrograms Chla.L-1 in both locations. Culturable fraction (measured as the percentage of CFU counts versus the total cell counts) was between 7% and 22% at Saroma-ko, and approximately 0.08% at Resolute Passage. When algal biomass exceeded 500 micrograms of Chla.L-1, both bacterial abundance and culturable fraction decreased significantly. There was a maximum threshold of algal biomass (between 500 and 800 micrograms of Chla.L-1) after which bacterial dynamics become negatively coupled to the algal biomass. These results suggest that bactericidal and/or bacteriostatic compounds from these extremely high algal concentrations could explain the decrease in bacterial abundance and culturability in bottom ice observed after the ice algae bloom.


Assuntos
Bactérias/crescimento & desenvolvimento , Eucariotos/crescimento & desenvolvimento , Água do Mar/microbiologia , Microbiologia da Água , Regiões Árticas , Clorofila/análise , Clorofila A , Gelo , Oceanos e Mares , Estações do Ano
14.
Arch Pediatr ; 7(4): 349-56, 2000 Apr.
Artigo em Francês | MEDLINE | ID: mdl-10793921

RESUMO

BACKGROUND: The aim of this study was to determine the influence of medical and non-medical factors on perinatal health in an underpriviledged area, the ex-coal mines of Lens (Pas-de-Calais). POPULATION AND METHODS: This prospective study concerned 1,000 women who delivered in the maternity hospital of Lens between January 5, 1993 and May 13, 1993. The relationships between preterm delivery, low birth weight and maternal socioeconomic and cultural characteristics were analyzed. RESULTS: The women included presented adverse pregnancy outcomes. Preterm delivery, low birth weight and neonatal transfer rates were respectively 6.9%, 7.3% and 12.7% higher than the average regional rates. In contrast with these results, antenatal care could be considered correct or even better. The poor socioeconomic status of the population appeared to be a very significant perinatal risk factor. CONCLUSION: At present, in an unfavourable regional conjuncture, socioeconomic and cultural factors have adverse effects on perinatal morbidity and mortality independent of medical factors like prenatal care. The prevention of poor perinatal outcome should be based on these data. Not the access to the health care system but the manner of dispensing health care should require great consideration.


Assuntos
Política de Saúde , Bem-Estar do Lactente , Recém-Nascido de Baixo Peso , Recém-Nascido Prematuro , Adulto , Serviços de Saúde da Criança , Características Culturais , Feminino , França , Humanos , Recém-Nascido , Masculino , Serviços de Saúde Materna , Gravidez , Resultado da Gravidez , Classe Social
15.
J Biol Chem ; 275(7): 4840-7, 2000 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-10671519

RESUMO

The "MAN antigens" are polypeptides recognized by autoantibodies from a patient with a collagen vascular disease and localized to the nuclear envelope. We now show that one of the human MAN antigens termed MAN1 is a 82.3-kDa protein with an amino-terminal domain followed by two hydrophobic segments and a carboxyl-terminal tail. The MAN1 gene contains seven protein-coding exons and is assigned to human chromosome 12q14. Its mRNA is approximately 5.5 kilobases and is detected in several different cell types that were examined. Cell extraction experiments show that MAN1 is an integral membrane protein. When expressed in transfected cells, MAN1 is exclusively targeted to the nuclear envelope, consistent with an inner nuclear membrane localization. Protein sequence analysis reveals that MAN1 shares a conserved globular domain of approximately 40 amino acids, which we term the LEM module, with inner nuclear membrane proteins lamina-associated polypeptide 2 and emerin. The LEM module is also present in two proteins of Caenorhabditis elegans. These results show that MAN1 is an integral protein of the inner nuclear membrane that shares the LEM module with other proteins of this subcellular localization.


Assuntos
Proteínas de Caenorhabditis elegans , Proteínas de Ligação a DNA , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Membrana Nuclear/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Timopoietinas/química , Sequência de Aminoácidos , Sequência de Bases , Cromossomos Humanos Par 12 , Primers do DNA , DNA Complementar , Células HeLa , Humanos , Proteínas de Membrana/genética , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas Nucleares/genética , RNA Mensageiro/genética , Homologia de Sequência de Aminoácidos
16.
Med Pediatr Oncol ; 34(2): 106-10, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10657870

RESUMO

BACKGROUND: The prevalence, in unselected patients with acute lymphoblastic leukaemia (ALL), of clonal rearrangements suitable for minimal residual disease (MRD) studies has not been formally investigated. PROCEDURE: This was a prospective, demographic study of the frequency of molecular markers of MRD in all patients with ALL presenting over 5 years within the Northern Health Region of England (population 3.1 million). Presentation marrow samples were examined to detect informative markers. RESULTS: One hundred twenty-four children (age <15 years) developed non-Burkitt ALL. No material was available for study in 21. Eighty-six had clonal gene rearrangements (BCR/ABL, immunoglobulin heavy chain (IGH) and/or T cell receptor (TCR) gene rearrangements). All entered remission; 84 (68% of the original cohort) survived to become eligible for MRD studies. One hundred sixteen adults developed ALL, of whom 48 were not studied due to insufficient cellular material in the bone marrow aspirate or to logistical problems in central referral of samples from other hospitals. Material from elderly adults (age >55 years) was less likely to be sent for analysis, 36% vs. 59% (P = 0.024). Thirty-eight had BCR/ABL and/or IGH/TCR gene rearrangements. Thirty-one (27% of the original cohort) entered remission and became eligible for MRD studies. Informative gene rearrangements were more common in children than adults (83% vs. 63%, P < 0.003). CONCLUSIONS: The results reveal substantial potential, unintentional, selection bias. Large-scale multicentre studies of MRD in children may well produce clinically relevant and representative data. Those who mount similar studies in adults should not assume they will be similarly representative or as successful in accrual of material.


Assuntos
DNA de Neoplasias/sangue , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangue , Adolescente , Adulto , Biomarcadores/sangue , Criança , Pré-Escolar , Rearranjo Gênico , Humanos , Lactente , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Recidiva
17.
Development ; 127(3): 631-41, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10631183

RESUMO

The generation of calcium oscillations at fertilisation and during mitosis appears to be controlled by the cell cycle machinery. For example, the calcium oscillations in oocytes and embryos occur during metaphase and terminate upon entry into interphase. Here we report the manipulation of sperm-triggered calcium oscillations by cyclin-dependent kinase (CDK) activity, the major component of maturation/M phase promoting factor (MPF). To control the CDK activity we microinjected mRNAs encoding full-length GFP-tagged cyclin B1 or a truncated and therefore stabilised form of cyclin B1 ((delta)90) into unfertilised oocytes. In the presence of full-length cyclin B1, the calcium oscillations terminate when cyclin B1 levels fall along with the concomitant fall in the associated CDK activity. In addition, when the CDK activity is elevated indefinitely with (delta)90 cyclin B1, the calcium oscillations also continue indefinitely. Finally, in oocytes that contain low mitogen-activated protein (MAP) kinase activity and elevated CDK activity, the sperm-triggered calcium oscillations are again prolonged. We conclude that the CDK activity of the ascidian oocyte can be regarded as a positive regulator of sperm-triggered calcium oscillations, a finding that may apply to other oocytes that display sperm-triggered calcium oscillations at fertilisation. Furthermore, these findings may have a bearing upon the mitotic calcium signals of early embryos.


Assuntos
Cálcio/metabolismo , Ciclina B/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Oócitos/fisiologia , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/fisiologia , Urocordados/fisiologia , Animais , Butadienos/farmacologia , Ciclina B/genética , Ciclina B1 , Inibidores Enzimáticos/farmacologia , Feminino , Cinética , Masculino , Microinjeções , Nitrilas/farmacologia , Oócitos/efeitos dos fármacos , Oscilometria , Biossíntese de Proteínas , Proteínas Quinases/metabolismo , Purinas/farmacologia , RNA Mensageiro/genética , Proteínas Recombinantes de Fusão/metabolismo , Roscovitina
18.
Exp Cell Res ; 250(2): 439-51, 1999 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-10413598

RESUMO

The murine monoclonal antibody 2A7 was found to react specifically with a 85-kDa human protein which is distributed throughout the nuclear interior in interphase and becomes associated with condensed chromosomes during mitosis. The 2A7 epitope was not detected in cells from other species. Two-dimensional immunoblotting analysis of HeLa cell homogenates further indicated that the 85-kDa polypeptide species recognized by the 2A7 antibody corresponds to an acidic protein which may be complexed in vivo within high-molecular-weight protein structures. Immunofluorescence monitoring of the 2A7 staining pattern during in situ preparation of nuclear matrices from HeLa cells demonstrated that the nucleoplasmic fraction of the antigen is readily solubilized by detergent and salts, whereas the nucleolar fraction resists detergent/salt extraction and DNase digestion, to be released only upon RNase activity. Mobility assays in human-mouse heterokaryons provided evidence that the 2A7 antigen is a nucleocytoplasmic shuttling protein. The nuclear distribution of this antigen remained unchanged upon drug-induced inhibition of RNA synthesis but was markedly altered by heat shock stress. All together, the data presented here suggest that the 2A7 antigen may have a function in RNA metabolism.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos/metabolismo , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Proteínas/metabolismo , Animais , Especificidade de Anticorpos , Antígenos/química , Antígenos/imunologia , Desoxirribonuclease I/metabolismo , Resposta ao Choque Térmico , Humanos , Células Híbridas/citologia , Células Híbridas/metabolismo , Interfase , Ponto Isoelétrico , Camundongos , Microscopia de Fluorescência , Peso Molecular , Matriz Nuclear/metabolismo , Proteínas/química , Proteínas/imunologia , RNA Mensageiro/biossíntese , RNA Mensageiro/metabolismo , Ribonuclease Pancreático/metabolismo , Solubilidade , Especificidade da Espécie , Células Tumorais Cultivadas
19.
J Cell Sci ; 112 ( Pt 5): 749-59, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9973608

RESUMO

Lamina-associated polypeptides 2 (LAP2alpha, beta, gamma)/thymopoietins (TPalpha, beta, gamma) are a family of proteins that are generated by alternative splicing from a single gene. These proteins have been primarily characterized in mammals. One member of this protein family, the integral membrane protein LAP2beta/TPbeta, has been localized to the inner nuclear membrane of somatic cells where it binds to chromatin and B-type lamins. By cDNA cloning we have characterized XLAP2, a Xenopus homologue of the mammalian LAP2beta. Using LAP2-specific antibodies, the Mr 68,000 XLAP2 was found to be the only member of the LAP2/TP family expressed in somatic cells and adult tissues. XLAP2 was not detected in oocytes, eggs and in early embryos up to the gastrula stage at the mRNA and protein level demonstrating that it is not synthesized from maternal mRNA. In counterpart oocytes, eggs, and embryos contained one LAP2-related integral membrane proteins of Mr 84,000. Northern blot analysis with the XLAP2 cDNA showed that a single hybridizing mRNA band of 1.8-2.0 kb was present in Xenopus somatic cells whereas two other hybridizing mRNA species of 2.8-3.0 and 0. 9-1.1 kb were present in oocytes, eggs and early embryos. All together, these results indicated that at least three distinct LAP2-related proteins might be expressed in Xenopus. The LAP2/TP protein of Mr 84,000 is present in the early embryos but its amount decreases during embryogenesis concomitant with the increase of XLAP2 in the embryo. Our results are the first description of the developmentally regulated expression of integral nuclear envelope proteins during early embryogenesis.


Assuntos
Proteínas de Ligação a DNA , Proteínas de Membrana/genética , Proteínas Nucleares/genética , Xenopus/embriologia , Xenopus/genética , Sequência de Aminoácidos , Animais , Linhagem Celular , Clonagem Molecular , DNA Complementar/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Células HeLa , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Dados de Sequência Molecular , Peso Molecular , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Oócitos/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Homologia de Sequência de Aminoácidos , Xenopus/metabolismo
20.
Histochem J ; 30(9): 617-25, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9870762

RESUMO

Using fluorescence microscopy, the mouse monoclonal antibody 2G2 was found to label mitochondria in human cells, as assessed by double staining with either Rhodamine 123 or a polyclonal antibody to mitochondrial matrix HSP-60 proteins. No reactivity to the 2G2 antibody was detected in cells from mouse, rat and chicken. Immunoblotting analysis demonstrated that the 2G2 antigen corresponds to a human protein with a relative mobility of 110kDa and an approximate isoelectric point of 6.5 that co-partitions with HSP-60 proteins during isolation of mitochondria from HeLa cells. Close examination of the 2G2 staining pattern in HeLa and Fanconi's anaemia cells revealed differences in the morphology and organization of mitochondria in these two cell types. In HeLa cells, mitochondria appear as individual tubular compartments of variable length and are closely associated with vimentin filaments, particularly at the periphery of the nucleus. In Fanconi's anaemia cells, mitochondria have a filamentous shape and form an interconnected cytoplasmic reticulum running in parallel with both vimentin filaments and microtubules. After stabilization with aldehyde- or alcohol-based fixation protocols that optimize the preservation of cytoskeletal components, the epitope targeted by the 2G2 antibody may serve as a valuable marker in the investigation of relationships between mitochondria and other cellular structures in human cells.


Assuntos
Anticorpos Monoclonais/imunologia , Mitocôndrias/imunologia , Proteínas/imunologia , Células 3T3 , Animais , Especificidade de Anticorpos , Linhagem Celular , Anemia de Fanconi , Células HeLa , Humanos , Camundongos , Microtúbulos/metabolismo , Ratos , Coloração e Rotulagem
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