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1.
Oral Dis ; 21(3): 349-54, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25158861

RESUMO

OBJECTIVE: We conducted a cross-sectional study to describe the prevalence and correlates of type-specific human papillomavirus (HPV) DNA in the oral cavities of persons with Fanconi anemia. MATERIALS AND METHODS: Oral swabs were collected from 67 participants with Fanconi anemia and tested for 27 HPV genotypes using polymerase chain reaction-based methods. RESULTS: Participants were a mean of 18.6 (standard deviation, 10.0) years of age (range 4-47 years). The prevalence of oral HPV infection was 7.5%, and the prevalence of high-risk HPV infection was 6.0%. HPV type 16 was not detected in any samples. Prevalence was higher in adults than in children (13.3% vs 2.7% in those ≥18 vs <18 years of age). Among adults, prevalence was higher in males than in females (25.0% vs 9.1%, respectively). CONCLUSIONS: Prevalence of oral HPV infection in persons with Fanconi anemia was comparable to estimates from other studies in the general population. However, in contrast to previous studies, we did not identify HPV type 16 (the type found in most HPV-related head and neck cancers) in any participants.


Assuntos
Anemia de Fanconi/virologia , Doenças da Boca/epidemiologia , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Estudos Transversais , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Boca/virologia , Doenças da Boca/virologia , Papillomaviridae/genética , Infecções por Papillomavirus/virologia , Prevalência , Fatores Sexuais , Adulto Jovem
2.
J Clin Invest ; 104(11): R55-62, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10587528

RESUMO

Several problems limit the application of gene transfer to correct the cystic fibrosis (CF) Cl(-) transport defect in airway epithelia. These include inefficient transduction with vectors applied to the apical surface, a low rate of division by airway epithelial cells, failure of transgene expression to persist, and immune responses to vectors or vector-encoded proteins. To address these issues, we used a feline immunodeficiency virus-based (FIV-based) vector. FIV vector formulated with a calcium chelator transduced fully differentiated, nondividing human airway epithelia when applied to the apical surface. FIV-based vector encoding the cystic fibrosis transmembrane conductance regulator cDNA corrected the Cl(-) transport defect in differentiated CF airway epithelia for the life of the culture (>3 months). When this approach was applied in vivo, FIV vector expressing beta-galactosidase transduced 1-14% of adult rabbit airway epithelia. Transduced cells were present in the conducting airways, bronchioles, and alveoli. Importantly, gene expression persisted, and cells with progenitor capacity were targeted. FIV-based lentiviral vectors may be useful for the treatment of genetic lung diseases such as CF. This article may have been published online in advance of the print edition.


Assuntos
Regulador de Condutância Transmembrana em Fibrose Cística/genética , Terapia Genética/métodos , Vírus da Imunodeficiência Felina/genética , Pulmão/patologia , Animais , Cloretos/metabolismo , Fibrose Cística/terapia , DNA Complementar/genética , Células Epiteliais , Técnicas de Transferência de Genes , Vetores Genéticos , Humanos , Fatores de Tempo , Traqueia/metabolismo , Transdução Genética , beta-Galactosidase/genética
3.
Cancer Res ; 52(20): 5647-55, 1992 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-1382844

RESUMO

Carcinoembryonic antigen (CEA) is a member of the immunoglobulin gene superfamily with one predicted variable domain-like region (N domain; 108 amino acids) and three sets of constant domain-like regions (A1B1, A2B2, and A3B3; 92 amino acids for A domains and 86 amino acids for B domains). In addition, CEA possesses two signal peptides, one at the amino terminus and one at the carboxyl terminus. Both are removed during posttranslational processing, with the one at the carboxyl terminus being replaced by a glycosylphosphatidylinositol (GPI) moiety. We have previously expressed the full length complementary DNA clone for CEA in Chinese hamster ovary cells and murine L cells, demonstrating proper processing of nascent polypeptide chains to mature, fully glycosylated CEA including the GPI anchor. Using the same full length CEA complementary DNA clone and the polymerase chain reaction, we have now constructed expression clones for secreted versions of the N domain, the A3B3 domain, and the A3 and B3 subdomains. The clones were expressed in HeLa cells using the beta-actin promoter. A stop codon was introduced at the end of the A3B3 and the A3 and B3 domains to allow secretion instead of retention on plasma membranes with the GPI anchor. Expressed products were purified to homogeneity by affinity chromatography using monoclonal antibodies specific for each domain and by reversed phase high pressure liquid chromatography. Purified domains were characterized by Western blotting, antibody binding and inhibition studies, amino-terminal sequence and amino acid analyses, and laser desorption/time of flight mass spectrometry. These analyses revealed that the monomeric N domain is of size 15,990, with a glycosylation mass of about 4100, in good agreement with two N-linked glycosyl units of about mass 2100. There is some evidence that the N domain forms dimers. The N domain reacted with antibodies specific for this domain with an affinity similar to that of intact CEA. The A3B3 domain had a mass of 34,462, with a glycosylation mass of 14,900, in good agreement with seven N-linked glycosylation sites of average mass 2100. The A3B3 domain reacted only with antibodies specific for this domain, with a slightly lower affinity than that of native CEA. The amino-terminal sequences of the N domain and A3B3 domain proteins demonstrated proper processing of the signal peptide.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Antígeno Carcinoembrionário/imunologia , Epitopos/análise , Imunoglobulinas/análise , Sequência de Aminoácidos , Anticorpos Monoclonais/análise , Sequência de Bases , Sítios de Ligação de Anticorpos , Ligação Competitiva , Western Blotting , Antígeno Carcinoembrionário/genética , Antígeno Carcinoembrionário/isolamento & purificação , Clonagem Molecular , Epitopos/imunologia , Epitopos/isolamento & purificação , Regulação Neoplásica da Expressão Gênica , Glicosilação , Células HeLa , Humanos , Imunoglobulinas/química , Lasers , Espectrometria de Massas , Dados de Sequência Molecular
4.
Arch Neurol ; 48(8): 866-70, 1991 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-1898265

RESUMO

Index finger tremor accompanying voluntary movement was studied in 19 age-matched control subjects and in 19 grain industry employees chronically exposed to carbon disulfide-based fumigants. Visual judgments of tremor amplitude made by neurologists during clinical examinations equaled the sensitivity of computerized tremor amplitude measurements. Tremor frequency variations detectable only with computerized measurement were present in grain workers with and without increased tremor amplitudes. Frequency differences discriminated between normal subjects and 74% of the grain workers. The distribution of tremor frequency power in the grain workers was often sequestered at 5 to 7 Hz, reminiscent of tremor in idiopathic Parkinson's disease. These findings suggest that the measurement of subtle tremor frequency changes may provide an early indication of chronic carbon disulfide poisoning.


Assuntos
Dissulfeto de Carbono/efeitos adversos , Dedos , Doenças Profissionais/induzido quimicamente , Praguicidas/efeitos adversos , Tremor/induzido quimicamente , Adulto , Idoso , Agricultura , Eletrofisiologia , Elevadores e Escadas Rolantes , Dedos/fisiopatologia , Humanos , Pessoa de Meia-Idade , Contração Muscular , Doenças Profissionais/diagnóstico , Doenças Profissionais/fisiopatologia , Transdutores , Tremor/diagnóstico , Tremor/fisiopatologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-10755210

RESUMO

In this review, we describe technical advancements of retroviral vectors to address issues of safety, titer, and clinical scale manufacturing to produce high-quality retroviral vector preparations that have made direct intratumoral administration of cytokine encoding recombinant vectors a feasible cancer therapy in the clinic. We also review possible further advances in retroviral vector design, which may prove important in expanding these clinical applications.


Assuntos
Citocinas/genética , Vetores Genéticos , Neoplasias/terapia , Retroviridae/genética , Vetores Genéticos/efeitos adversos , Vetores Genéticos/normas , Humanos
6.
Neuroreport ; 11(12): 2669-73, 2000 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-10976941

RESUMO

Our data demonstrate that vectors derived from recombinant feline immunodeficiency virus (rFIV) and adeno-associated virus type 5 (rAAV5) transduce cerebellar cells following direct injection into the cerebellar lobules of mice. Both recombinant viruses mediated gene transfer predominantly to neurons, with up to 2500 and 1500 Purkinje cells transduced for rAAV5 or rFIV-based vectors, respectively. The vectors also transduced stellate, basket and Golgi neurons, with occasional transduction of granule cells and deep cerebellar nuclei. rAAV5 also spread outside the cerebellum to the inferior colliculus and ventricular epithelium, while rFIV demonstrated the ability to undergo retrograde transport to the physically close lateral vestibular nuclei. Thus, AAV5 and FIV-based vectors show promise for targeting neurons affected in the hereditary spinocerebellar ataxias. These vectors could be important tools for unraveling the pathophysiology of these disorders, or in testing factors which may promote neuronal survival.


Assuntos
Cerebelo/fisiologia , Dependovirus/genética , Vetores Genéticos , Vírus da Imunodeficiência Felina/genética , Neurônios/fisiologia , Transdução Genética , Transgenes , Animais , Transporte Biológico Ativo , Cerebelo/citologia , Camundongos , Camundongos Endogâmicos C57BL , Células de Purkinje/enzimologia , beta-Galactosidase/genética , beta-Galactosidase/metabolismo
7.
Am Psychol ; 52(2): 154-66, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9104089

RESUMO

Behavioral research and surveillance activities are conducted across the Centers for Disease Control and Prevention (CDC). This article highlights activities in 4 program areas: violence against women, tuberculosis elimination, HIV prevention, and occupational health. The unique constraints and opportunities of each organization and program focus have shaped the way research has developed in each of these areas. Behavioral scientists also face many common challenges at CDC. Despite the difficulties of integrating behavioral research into an institution that historically has focused on biomedical and epidemiological research, behavioral scientists have made important contributions to public health. Many opportunities remain for psychologists to translate theory and operationalize constructs for use in solving important public health problems.


Assuntos
Ciências do Comportamento/tendências , Centers for Disease Control and Prevention, U.S./tendências , Relações Interprofissionais , Serviços Preventivos de Saúde/tendências , Feminino , Previsões , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Vigilância da População , Problemas Sociais/prevenção & controle , Problemas Sociais/tendências , Estados Unidos
8.
Am Psychol ; 45(10): 1146-58, 1990 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-2252233

RESUMO

The National Institute for Occupational Safety and Health (NIOSH) recognizes psychological disorders as a leading occupational health problem. This document, developed by a NIOSH working group led by the present authors, represents a first attempt to fashion a comprehensive national strategy to protect and promote the psychological health of workers. Roles are identified for industry, labor, government, and academia. Key initiatives include (a) steps to improve working conditions and employee mental health services and (b) increased research and surveillance to advance understanding of the problem. Because work-related psychological disorders appear to be a rapidly developing problem lacking complete definition in terms of scope and etiology, this strategy is not to be considered a final statement of NIOSH policy.


Assuntos
Transtornos Mentais/prevenção & controle , Doenças Profissionais/prevenção & controle , Estresse Psicológico/complicações , Humanos , National Institute for Occupational Safety and Health, U.S. , Fatores de Risco , Estados Unidos
9.
Biol Psychol ; 42(3): 269-86, 1996 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-8652748

RESUMO

The present study tested the hypothesis that performance would improve when the work rhythm of a highly repetitive task was synchronous with a worker's internal physiological rhythms. Experienced office workers (n = 20) used video display terminals (VDTs) to perform a repetitive, self-paced data-entry task in a simulated office environment over a 2-day period. Each work day consisted of six 40-min work periods. Work rhythm changes were induced by varying input data field lengths (3-13 characters) across eleven of the twelve work periods. The degree of synchronization between the work and breathing rhythms, and also between the work rhythm and variations in the interbeat interval, was scored using cross-spectral analysis. Synchronization scores were then used to predict keying performance using multiple regression analysis. The degree of synchronization between the work and breathing rhythms was not predictive of performance. However, increased synchronization between the work and cardiac rhythms was predictive of (a) increased keystroke output, (b) lower error rate and (c) lower correction rate. The results suggest that performance in repetitive VDT work might improve if the task is designed to promote work-physiological synchronization.


Assuntos
Nível de Alerta/fisiologia , Tédio , Terminais de Computador , Comportamento Estereotipado/fisiologia , Carga de Trabalho/psicologia , Adolescente , Adulto , Feminino , Frequência Cardíaca/fisiologia , Humanos , Psicofisiologia , Respiração/fisiologia , Percepção do Tempo/fisiologia , Tolerância ao Trabalho Programado
10.
Scand J Work Environ Health ; 23(6): 450-7, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9476809

RESUMO

OBJECTIVES: The purpose of this study was to investigate work climate factors and structural job aspects as predictors of workplace violence, with particular attention to the relative influence of both sets of factors. METHODS: Telephone survey data collected by a large midwestern insurance company were analyzed. Interviewers asked 598 full-time workers about their work climate, structural job aspects, and subject and workplace demographics, all of which were used as predictor variables in regression analyses. The participants were also asked about incidents of threats, harassment, physical attacks, and fear of becoming a victim of workplace violence, all of which were used as outcome measures. RESULTS: Separate logistic regressions were carried out for each of the outcome measures. The study identified a variety of factors which appear to place workers at risk of nonfatal occupational violence. Work climate variables, such as co-worker support and work group harmony, were predictive of threats, harassment, and fear of becoming a victim of violence. Structural aspects of the job, such as work schedule, were also significant in predicting threats and fear of becoming a victim of violence, but they were not predictive of harassment. CONCLUSIONS: This is the first study which suggests that both work climate and structural aspects of work may be important in promoting workplace violence. This finding suggests that intervention strategies should consider organizational and climate issues in addition to basic security measures.


Assuntos
Saúde Ocupacional/estatística & dados numéricos , Comportamento Social , Estresse Psicológico/etiologia , Violência/psicologia , Adulto , Medo , Feminino , Inquéritos Epidemiológicos , Hostilidade , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição Aleatória , Estados Unidos , Violência/estatística & dados numéricos , Local de Trabalho
11.
Ind Health ; 37(2): 199-211, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10319568

RESUMO

There is growing concern that rapidly changing patterns of work organization and employment pose risk for occupational illness and injury. In the present article, we assert that these changes create new needs and opportunities for research and practice by psychologists in the area of work organization and health. We begin with an historical overview of the contribution of psychologists to the occupational safety and health field, and to the study of work organization and health. We then describe new initiatives by the American Psychological Association and national health organizations in the United States and Europe to frame a new field of study--called "occupational health psychology"--that focuses on the topic of work organization and health. We conclude with a discussion of emerging research needs and trends within this field.


Assuntos
Acidentes de Trabalho/prevenção & controle , Acidentes de Trabalho/psicologia , Doenças Profissionais/prevenção & controle , Doenças Profissionais/psicologia , Psicologia Industrial/organização & administração , Especialização/tendências , Acidentes de Trabalho/estatística & dados numéricos , Emprego/organização & administração , Ergonomia , Humanos , Avaliação das Necessidades , Doenças Profissionais/etiologia , Inovação Organizacional , Pesquisa , Fatores de Risco
12.
Appl Ergon ; 28(1): 9-16, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9414336

RESUMO

Concerns have arisen that the keyboard is a causal factor in the development of work-related musculoskeletal disorders (WRMDs) among video display terminal (VDT) operators. A number of alternative keyboard designs have been developed with altered geometry in an effort to improve comfort in keyboard operation. However, few data are available to substantiate whether these new keyboard designs are actually effective in reducing discomfort and musculoskeletal problems in users. The purpose of this study was to provide data on the efficacy of certain alternative keyboard design features (e.g. splitting the keyboard in half, and laterally inclining the keyboard halves) in reducing fatigue and musculoskeletal discomfort among keyboard operators. The study also explored the effects of these design features on performance. Fifty subjects performed a text-entry task for one day on a standard keyboard, then were assigned to one of five keyboard conditions for an evaluation period of two days (i.e. 10 subjects/condition). Outcome measures included performance (i.e. keystrokes/h, errors/h) and self-report measures of discomfort and fatigue. The results indicated an initial decline in productivity when subjects began typing on two of the alternative keyboards, but these productivity losses were recovered within the two-day evaluation period. The results also indicated no significant differences between keyboard conditions in discomfort and fatigue. These results suggest a minimal impact of the keyboard design features examined in this study on productivity, comfort and fatigue, at least after two days of exposure.


Assuntos
Periféricos de Computador , Sistemas Homem-Máquina , Saúde Ocupacional , Adulto , Desenho de Equipamento , Feminino , Humanos , Fadiga Muscular , Análise e Desempenho de Tarefas
13.
Appl Ergon ; 18(3): 183-6, 1987 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15676620

RESUMO

Evidence of injury to the pisiform and dorsal sensory branch of the ulnar nerve in a video display terminal (VDT) operator is presented. The subject has performed data entry work via keyboard for 20 years and has the common habit of resting her wrist against the leading edge of the keyboard. Skin lesions have been observed in other keyboard operators who similarly support their limbs. The opportunity for this type of trauma has gone unreported (and apparently unrecognised) in the ergonomics literature, which generally advocates wrist support to reduce upper extremity fatigue and improve wrist-hand posture. The present case study indicates a need for further evaluation of the dynamics of wrist rest use and of the design of support systems such that forces acting upon the wrist or palm can be controlled. Suggestions are offered in this regard.

16.
Gene Ther ; 12(14): 1089-98, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16003340

RESUMO

Replication defective vectors derived from simple retroviruses or the more complex genomes of lentiviruses continue to offer the advantages of long-term expression, cell and tissue specific tropism, and large packaging capacity for the delivery of therapeutic genes. The occurrence of adverse events caused by insertional mutagenesis in three patients in a gene therapy trial for X-linked SCID emphasizes the potential for problems in translating this approach to the clinic. Several genome-wide studies of retroviral integration are now providing novel insights into the integration site preferences of different vector classes. We review recent developments in vector design, integration, biosafety, and production.


Assuntos
Terapia Genética/tendências , Vetores Genéticos/genética , Lentivirus/genética , Retroviridae/genética , Técnicas de Transferência de Genes , Terapia Genética/efeitos adversos , Terapia Genética/métodos , Humanos , Mutagênese Insercional
17.
Somat Cell Mol Genet ; 26(1-6): 99-129, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12465464

RESUMO

Why is feline immunodeficiency virus (FIV) such an appealing candidate for gene therapy vector development? Phylogenetic analysis suggests FIV is only distantly related to the primate lentiviruses, and despite repeated exposure, neither seroconversion nor other detectable evidence of human infection occurs. FIV naturally infects diverse Felidae worldwide, including the domestic cat. Here, the disease progression parallels the immunodeficiency caused by HIV, and for that reason, FIV and the cat provide an excellent model for anti-virals and AIDS vaccine research. Simple genome organization also facilitates vector development and analysis: FIV has only three accessory/regulatory proteins. To overcome FIV's cat-specific tropism, feline vectors are equipped with hybrid LTRs, since the FIV LTR shows low activity in human cells. Recombinant FIV vectors generate titers comparable to other lentiviral systems, are capable of incorporating heterologous envelopes and efficiently transduce dividing and nondividing cells in the presence and absence of the accessory proteins in vitro. Compared to HIV vectors, FIV vector development is still in its infancy, but initial in vivo data in various species and tissues indicate long-term gene expression at therapeutic levels, and thus FIV vectors hold great promise. Future efficacy studies in animal models and primates will determine the FIV vectors' suitability for gene therapy. The design of recombinant FIV vectors incorporates safety features described for primate lentiviral vectors with the benefit that biosafety testing of FIV vectors can occur in the natural host. Currently, FIV vectors are generated in a transient fashion, but the availability of a stable producer system amenable to better characterization and scale-up will considerably increase the potential for use of FIV vectors in the clinic.


Assuntos
Vírus da Imunodeficiência Felina/genética , Animais , Gatos , Síndrome de Imunodeficiência Adquirida Felina , Técnicas de Transferência de Genes , Genes gag , Vetores Genéticos
18.
Hum Factors ; 33(2): 151-67, 1991 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1860702

RESUMO

Self-report data on musculoskeletal discomfort were collected from several hundred VDT users in two agencies of a state government. Aspects of worker posture and workstation design were objectively assessed for 40 of the VDT users. Multiple regression analyses were used to examine the relationship between these ergonomic variables and musculoskeletal discomfort. Effects of ergonomic factors on musculoskeletal discomfort were clearly evident in the analyses. Regression models explained up to 38% of the variance in discomfort at different body sites. Of special interest was that leg discomfort increased with low, soft seat pans, suggesting that postural constraint is more important than thigh compression as a risk factor for leg discomfort in VDT work. In addition, arm discomfort increased with increases in keyboard height above elbow level, supporting arguments for low placement of the keyboard. Finally, high levels of neck and shoulder girdle discomfort observed in the study population suggest the need for further attention to the control of cervicobrachial pain syndromes in VDT work.


Assuntos
Terminais de Computador , Músculos/fisiopatologia , Doenças Profissionais/fisiopatologia , Dor/fisiopatologia , Postura/fisiologia , Adulto , Neurite do Plexo Braquial/fisiopatologia , Transtornos Traumáticos Cumulativos/fisiopatologia , Feminino , Humanos , Masculino , Fatores de Risco
19.
Undersea Biomed Res ; 17(2): 109-20, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2108518

RESUMO

The behavioral effects of elevated PACO2 were examined to clarify risks due to CO2 retention in diving. In two separate laboratory studies, experienced divers breathed 6% CO2 mixtures under normobaric conditions. Normoxic study: Subjects (n = 8) first breathed air (control); then 6% CO2, 21% O2, balance N2 (exposure); and then air again (postexposure). Hyperoxic study: Subjects (n = 10) first breathed 100% O2; then 6% CO2 in O2; and then O2 again. Subjects performed a test battery in each condition. In the control and postexposure conditions, tests consisted of simple and choice reaction time, postural sway, tremor, and hand steadiness. In the exposure conditions, only the simple and choice reaction time tests were performed. No significant performance decrements during CO2 exposure were found in either study. However, regression analyses indicated that changes in postural sway, tremor, and decision-making time after normoxic CO2 exposure were proportional to decrements in individual end-tidal PCO2 levels following CO2 exposure. We conclude that divers may be at risk for performance impairment immediately after a period of CO2 retention.


Assuntos
Comportamento/fisiologia , Dióxido de Carbono/fisiologia , Mergulho/efeitos adversos , Adolescente , Adulto , Eficiência , Feminino , Humanos , Masculino , Postura/fisiologia , Tempo de Reação , Análise de Regressão , Tremor/etiologia
20.
Infect Immun ; 59(7): 2485-93, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1675630

RESUMO

Nonspecific cross-reacting antigen (NCA) is a well-characterized membrane glycoprotein on granulocytes, macrophages, and lung epithelium. Structural studies at the protein and genomic levels have revealed that NCA is a member of the immunoglobulin supergene family, and hybridization studies showed that the transcript level of NCA is induced by treatment with gamma interferon. These studies, as well as the expression of NCA on granulocytes, suggest a role for NCA in immune response. For a first step in studying this possible role, we have examined the binding of two glycoforms of NCA designated NCA-50 (Mr, 50,000) and TEX-75 (Mr, 75,000). Here we report the results from binding assays which demonstrate carbohydrate-mediated binding of Escherichia coli expressing type 1 fimbriae and of isolated type 1 fimbriae to NCA-50. TEX-75 did not bind to the purified fimbriae but bound slightly to the bacterial strain. Inhibition studies showed that the binding to NCA-50 involved interaction of mannose moieties on NCA-50 and lectins on the fimbriae. The binding of NCA-50 to bacterial fimbriae was confirmed by electron microscopy studies, using immunolabeling techniques. In addition, we show that the surface expression of NCA-50 (and presumably of other NCA species) on isolated polymorphonuclear leukocytes is increased following activation with the bacterial peptide formylmethionyl-leucyl-phenylalanine, consistent with a role for NCA in immune response.


Assuntos
Antígenos de Neoplasias , Moléculas de Adesão Celular , Escherichia coli/metabolismo , Fímbrias Bacterianas/fisiologia , Glicoproteínas de Membrana/metabolismo , Aderência Bacteriana , Carboidratos/análise , Escherichia coli/citologia , Fímbrias Bacterianas/ultraestrutura , Humanos , Técnicas In Vitro , Glicoproteínas de Membrana/química , Microscopia Eletrônica , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Ligação Proteica
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