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1.
Cancer Res ; 52(19): 5198-203, 1992 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-1394123

RESUMO

This is a retrospective study on 162 node-negative patients, with both biochemical and clinical factors being measured for determination of prognostic markers. Steroid receptors were measured on all tumors, while tumor size, histological grade, ploidy status, and cell cycle kinetics indicators could not be found or measured on 25 or less of the patient group. The primary focus of this study was the measurement of cathepsin D, analyzed by two different procedures, and 161 of the 162 patients had at least one value. The antigenic assay was performed using the US-CIS kit, and it was sensitive and reproducible. A biochemical assay using the enzymatic activity of cathepsin D was developed, and it gave proportional values, compared to the antigenic assay values (r2 = 0.79). Our results indicated that the mean antigenic levels were 20% higher than the biochemical assay levels (P = 0.001). High levels of cathepsin D by the antigenic assay predicted poor relapse-free (P = 0.0001) and overall (P = 0.0004) survival. High levels of cathepsin D by the biochemical assay also predicted poor relapse-free (P = 0.031) and overall (P = 0.0013) survival. The cathepsin D values were still useful as predictors of outcome after multivariate analysis. Several other factors, such as grade and S phase, were useful as additional prognostic indicators. In conclusion, cathepsin D is the most useful marker in node-negative patients, and the analysis can be performed by both a biochemical and an antigenic assay.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Catepsina D/análise , Ensaios Enzimáticos Clínicos , Análise de Variância , Neoplasias da Mama/patologia , Neoplasias da Mama/ultraestrutura , Feminino , Seguimentos , Humanos , Imunoensaio/métodos , Linfonodos/patologia , Metástase Linfática/diagnóstico , Prognóstico , Modelos de Riscos Proporcionais , Receptores de Esteroides/análise , Estudos Retrospectivos
2.
Biochim Biophys Acta ; 1219(1): 228-32, 1994 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-7522056

RESUMO

We isolated a 15.5 kilobase pair DNA fragment that contains the 5' end of the human vitronectin receptor alpha subunit (alpha v) gene. The nucleotide sequence of the 5' flanking region, first exon and part of the first intron of the alpha v gene was determined. The sequence showed that the 5' end of the alpha v gene lies within a CpG island. The transcriptional initiation site was mapped 169 base pairs upstream of the alpha v translational initiation site. The 5' flanking region of the alpha v gene does not contain TATA or InR transcriptional control elements but does contain four Sp1 binding sites, two Ets binding sites and one GATA binding site. The identified alpha v gene 5' flanking region directed the expression of human growth hormone in transfected HeLa cells. Successive deletions of the 5' flanking region demonstrated a 222 bp region that exerts a strong positive effect on alpha v promoter activity.


Assuntos
Integrinas/genética , Regiões Promotoras Genéticas/genética , Receptores de Citoadesina/genética , Sequência de Aminoácidos , Sequência de Bases , Clonagem Molecular , Biblioteca Genômica , Humanos , Integrina alfaV , Integrinas/biossíntese , Dados de Sequência Molecular , RNA Mensageiro/genética , Receptores de Citoadesina/biossíntese , Receptores de Vitronectina , Proteínas Recombinantes de Fusão/biossíntese , Mapeamento por Restrição , Análise de Sequência de DNA
3.
Am J Prev Med ; 19(4): 245-52, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11064228

RESUMO

BACKGROUND: Despite rapid proliferation of descriptive studies of health care providers (HCPs) and protocols for identification and management of domestic violence (DV), few reliable instruments exist for assessing HCPs' attitudes, beliefs, and behaviors regarding this practice. This study describes the development and psychometric properties of a measure of attitudes, beliefs, and self-reported behaviors related to the identification and management of DV. METHODS: We used a multiphase study design to develop items across eight content domains. We administered an initial pool of 104 items to a pilot sample of 129 primary care providers (physicians, physician assistants, nurse practitioners, and medical assistants) in a large, urban health maintenance organization. Descriptive statistics, principal components, and reliability analyses were performed on each of the eight content domains. The analyses guided the deletion of items and development of additional items, yielding a 56-item pool. The items were then administered and re-analyzed with an independent sample of 246 HCPs. RESULTS: Six separate and reliable domains were identified: Perceived Self-Efficacy, System Support, Blame Victim, Professional Role Resistance/Fear of Offending Patient, Victim/Provider Safety, and Frequency of DV Inquiry. We found item domain Cronbach alpha to be acceptable, ranging from 0.73 to 0.91. The final overall measure had 39 items and an alpha of 0.88. Data are reviewed that support the measure's sensitivity to change in response to a training intervention. CONCLUSION: The measure provides a reliable method for assessing provider characteristics and training needs. It may also serve to evaluate training and policy interventions in DV.


Assuntos
Atitude do Pessoal de Saúde , Violência Doméstica , Pessoal de Saúde/estatística & dados numéricos , Feminino , Pesquisas sobre Atenção à Saúde , Pessoal de Saúde/educação , Humanos , Masculino , Projetos Piloto , Competência Profissional , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Estados Unidos
4.
Am J Prev Med ; 19(4): 253-63, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11064229

RESUMO

BACKGROUND: Diagnosis of domestic violence (DV) in primary care is low compared to its prevalence. Care for patients is deficient. Over a 1-year period, we tested the effectiveness of an intensive intervention to improve asking about DV, case finding, and management in primary care. The intervention included skill training for providers, environmental orchestration (posters in clinical areas, DV questions on health questionnaires), and measurement and feedback. METHODS: We conducted a group-randomized controlled trial in five primary care clinics of a large health maintenance organization (HMO). Outcomes were assessed at baseline and follow-up by survey, medical record review, and qualitative means. RESULTS: Improved provider self-efficacy, decreased fear of offense and safety concerns, and increased perceived asking about DV were documented at 9 months, and also at 21 months (except for perceived asking) after intervention initiation. Documented asking about DV was increased by 14.3% with a 3.9-fold relative increase at 9 months in intervention clinics compared to controls. Case finding increased 1.3-fold (95%, confidence interval 0.67-2.7). CONCLUSIONS: The intervention improved documented asking about DV in practice up to 9 months later. This was mainly because of the routine use of health questionnaires containing DV questions at physical examination visits and the placement of DV posters in clinical areas. A small increase in case finding also resulted. System changes appear to be a cost-effective method to increase DV asking and identification.


Assuntos
Violência Doméstica/prevenção & controle , Avaliação de Resultados em Cuidados de Saúde , Assistência ao Paciente/métodos , Atenção Primária à Saúde/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Intervalos de Confiança , Feminino , Humanos , Masculino , Prontuários Médicos , Pessoa de Meia-Idade , Razão de Chances , Reprodutibilidade dos Testes
5.
Toxicon ; 24(4): 403-11, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-2424145

RESUMO

A monoclonal antibody (A-Tox-653.1) selected for its reactivity in a dot immunoblot assay with denatured staphylococcal alpha-toxin has been isolated and its capacity to block the hemolytic and lethal activities of alpha-toxin measured. In addition, 'reactivity with monomer, hexamer, 125I-monoiodinated and CNBr peptides of alpha-toxin was studied. In all cases the reactions of the monoclonal antibody were compared to those obtained with anti-alpha-toxin rabbit hyperimmune serum. We find that while both the monoclonal antibody and the rabbit antiserum react with all forms of alpha-toxin, only the rabbit antiserum blocks hemolytic or lethal activity. Further, the rabbit antiserum reacts with CNBr fragments IV, V ad VII, whereas the monoclonal antibody reacts only with the carboxy terminal CNBr peptide VII. We conclude that, in solution, the carboxy terminal segment of alpha-toxin is relatively free and reaction with the monoclonal antibody neither impedes its binding to the specific receptor on the membrane nor interferes with formation of the hexamer complex.


Assuntos
Toxinas Bacterianas/imunologia , Proteínas Hemolisinas , Animais , Anticorpos Monoclonais , Colódio , Brometo de Cianogênio , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Epitopos/imunologia , Hemólise , Imunodifusão , Camundongos , Camundongos Endogâmicos BALB C , Fragmentos de Peptídeos/imunologia , Coelhos
6.
Violence Vict ; 13(4): 395-410, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10328446

RESUMO

Domestic violence as encountered in day-to-day practice is greatly underidentified. It is estimated that only 3% of cases are presently being identified, and practitioners are uncertain of what to do if a case is discovered. In this paper, a training program to improve identification and management of domestic violence (DV) in primary care and the providers' responses to the program are described. A multimodal training program was undertaken to demonstrate and practice the incorporation of didactic content into practice for the health care teams. Two medical centers from a large staff-model HMO were chosen at random from five volunteering for training. The entire adult health care medical center teams, including physicians, physician assistants, RNs, LPNs, medical assistants, and receptionists, were the recipients of the training. Assessment of provider valuation of the components of the training program was performed by administering a standardized 5-point Likert-scaled questionnaire 9 months after the training. This time interval was chosen because we were interested in lasting program effects. Core didactic content, such as the epidemiology of DV, identification and management of victims and batterers, and legal issues, was highly rated. Delivery of the content through role-playing, start-stop videos and presentations by former victims received lesser but solid support. Follow-up assessment 9 months post training demonstrates solid support for many components of the program: highest for specific information content areas, but strong for techniques and processes. The training program appears to be a promising method to improve provider skills in DV management.


Assuntos
Pessoal de Saúde/educação , Capacitação em Serviço/organização & administração , Atenção Primária à Saúde/métodos , Maus-Tratos Conjugais/diagnóstico , Maus-Tratos Conjugais/prevenção & controle , Adulto , Instituições de Assistência Ambulatorial , Currículo , Avaliação Educacional , Feminino , Seguimentos , Humanos , Masculino , Anamnese , Modelos Educacionais , Avaliação de Programas e Projetos de Saúde , Encaminhamento e Consulta , Inquéritos e Questionários , Ensino/métodos
9.
Infect Immun ; 62(2): 421-5, 1994 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8300202

RESUMO

Brain tissue and serum from mice intracerebrally injected with 1 microgram of staphylococcal alpha-toxin contained elevated amounts of a naturally occurring brain tissue component(s) called muscle-relaxing factor (MRF). MRF induced reversible, generalized, flaccid paralysis of mice after intracerebral but not intraperitoneal or intravenous administration. MRF (i) was soluble in Hanks balanced salt solution and in acidified (pH 2) Hanks balanced salt solution, in which it partitions into ethyl acetate, acetone, and methanol; (ii) was separated from some pigments by thin-layer chromatography on silica gel plates; (iii) did not comigrate with prostaglandin and leukotriene standards during high-pressure liquid chromatography with a mu Bondapak fatty acid column; and (iv) did not contain amino acids, exhibit absorption maxima at a wavelength range of 210 to 600 nm, or fluoresce when exposed to UV light. MRF has been detected in rabbit brain that has been stored frozen at -70 degrees C and has been enhanced in vitro in slices of both mouse and rabbit brain following incubation of the brain slices with staphylococcal alpha-toxin. Studies to identify the chemical nature of MRF and the mechanism by which, in mice, it induces reversible, flaccid paralysis of voluntary muscle are continuing.


Assuntos
Toxinas Bacterianas/toxicidade , Proteínas Hemolisinas/toxicidade , Proteínas Musculares/biossíntese , Relaxamento Muscular/efeitos dos fármacos , Staphylococcus , Animais , Toxinas Bacterianas/administração & dosagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Feminino , Proteínas Hemolisinas/administração & dosagem , Técnicas In Vitro , Injeções , Masculino , Camundongos , Proteínas Musculares/sangue , Proteínas Musculares/isolamento & purificação , Neurotoxinas/administração & dosagem , Neurotoxinas/toxicidade , Óxido Nítrico , Staphylococcus/patogenicidade
10.
Infect Immun ; 47(1): 37-40, 1985 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3965408

RESUMO

Calcium in millimolar concentrations protected rabbit erythrocytes from hemolysis caused by staphylococcal alpha-toxin. This effect was maximal at 30 mM CaCl2 and required the continued presence of calcium. The protection was not absolute and could be overcome by increased concentrations of alpha-toxin. Calcium did not block the binding of alpha-toxin to erythrocytes but inhibited the alpha-toxin-induced release of small ions from the cell as measured by 86Rb release. The transient removal of calcium was sufficient to abrogate its protective effect, suggesting that its action involves a reversible alteration in the state of the membrane. The three steps of the alpha-toxin-induced hemolytic sequence are: (i) binding to specific receptors, (ii) formation of transmembrane pores, and (iii) cell lysis. We concluded that calcium acted at step ii by impeding the lateral movement of alpha-toxin necessary to form the transmembrane hexamer pores.


Assuntos
Toxinas Bacterianas/toxicidade , Cloreto de Cálcio/farmacologia , Proteínas Hemolisinas , Hemólise/efeitos dos fármacos , Animais , Eritrócitos/efeitos dos fármacos , Cinética , Coelhos , Rubídio/sangue , Staphylococcus/patogenicidade
11.
JAMA ; 267(23): 3157-60, 1992 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-1593735

RESUMO

OBJECTIVE: To explore primary care physicians' experiences with domestic violence victims to determine the barriers to problem recognition and intervention in the primary care setting. DESIGN: Ethnography, a qualitative research method involving the use of open-ended, semistructured interviews. SETTING: An urban health maintenance organization serving a predominantly white, middle-income population. PARTICIPANTS: Thirty-eight physicians, predominantly family practitioners (89%), were interviewed. RESULTS: Analysis of the interviews revealed that physicians found exploring domestic violence in the clinical setting analogous to "opening Pandora's box." Their issues include lack of comfort, fear of offending, powerlessness, loss of control, and time constraints. CONCLUSION: This study revealed several barriers that physicians perceived as preventing them from comfortably intervening with domestic violence victims. These issues need to be addressed in training programs. Further studies should be done to assess generalizability of these findings to other groups of physicians.


Assuntos
Atitude do Pessoal de Saúde , Médicos de Família/psicologia , Maus-Tratos Conjugais , Violência , Humanos , Entrevistas como Assunto , Relações Médico-Paciente , Médicos de Família/estatística & dados numéricos , Estados Unidos , Saúde da População Urbana
12.
J Infect Dis ; 137(1): 44-9, 1978 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-624851

RESUMO

During a one-year period, 101 parakeets and parrots were submitted for laboratory examination. The birds were sick, dead, or from premises where morbidity had been observed. Tissue specimens from these birds were tested for the presence of Chlamydiapsittaci by two methods. A tissue culture system using McCoy cells treated with 5-iodo-2-deoxyuridine was found to be more sensitive than intraperitoneal inoculation of mice for isolation of the chlamydiae. Chlamydiae were recovered from 21 (34%) of 61 parakeets and 16 (40%) of 40 parrots tested. This high rate of infection persists despite the availability of effective chemotherapeutic regimens for control of chlamydial infection in psittacines. The origins of some of the infected birds were traced to aviaries where subsequent treatment with chlortetracycline was successful in eradication of the chlamydial infection. Other infected birds had been imported recently and could be traced back to quarantine centers where (by law) the birds received chemoprophylaxis for chlamydial infection. Our results suggest that this program is an administrative failure.


Assuntos
Reservatórios de Doenças , Psitacose/etiologia , Animais , Chlamydophila psittaci/isolamento & purificação , Efeito Citopatogênico Viral , Fígado/microbiologia , Periquitos , Papagaios , Baço/microbiologia
13.
Antimicrob Agents Chemother ; 18(5): 696-8, 1980 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-7447426

RESUMO

Recent Chlamydia trachomatis isolates were tested in a tissue culture system for susceptibility to tetracycline, erythromycin, rosaramicin, rifampin, and clindamycin. Rifampin was the most active drug (minimal inhibitory concentration, less than or equal to 0.02 microgram/ml). Tetracycline and rasaramicin were highly active, with a concentration of less than or equal to 0.25 microgram/ml being chlamydicidal. Clindamycin was least active on a weight basis, requiring up to 16 microgram/ml to prevent the passage of chlamydiae into a drug-free tissue culture system. Relative resistance to erythromycin was detected; two isolates were capable of limited replication in 1 microgram/ml.


Assuntos
Chlamydia trachomatis/efeitos dos fármacos , Eritromicina/farmacologia , Antibacterianos/farmacologia , Infecções por Chlamydia/microbiologia , Resistência Microbiana a Medicamentos
14.
Diagn Gynecol Obstet ; 3(2): 149-54, 1981.
Artigo em Inglês | MEDLINE | ID: mdl-7261865

RESUMO

An 85-year-old woman had a 7-year history of recurrent uterine adenosarcoma. One year after curettage-related uterine perforation, she developed a pelvic mass that was attached to the uterine serosa and was histologically identical to her endometrial lesions. The pelvic neoplasm probably resulted from implantation of tumor through the myometrial tear and is the first reported example of serosal adenosarcoma following myometrial perforation. The definition of sarcomatous stroma in Müllerian adenosarcoma, and thus its separation from adenofibroma, has not been delineated. A review of the literature indicates, however, that lesions recurring after hysterectomy have greater than three mitotic figures per 10 high-power fields. Incompletely excised neoplasms, treated by dilation and curettage only, often regrow, regardless of mitotic rate. Adenosarcoma may have a deceptively bland low-power pattern and must be differentiated from adenofibroma and benign polyps.


Assuntos
Neuroblastoma/patologia , Neoplasias Pélvicas/secundário , Neoplasias Uterinas/patologia , Idoso , Feminino , Humanos , Recidiva Local de Neoplasia , Neoplasias Pélvicas/etiologia , Perfuração Uterina/complicações
15.
J Gen Virol ; 73 ( Pt 4): 821-7, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1321877

RESUMO

Glycoprotein gIII of pseudorabies virus (PrV) is multifunctional. It plays a role in the stable adsorption of the virus to its host cells by interacting with a cellular heparin-like substance. It also affects both release of mature virus from infected cell types and virulence. Thus, although non-essential for growth in vitro, gIII plays a central role in the biology of the virus. The primary attachment of a mutant, PrV2, which has an in-frame internal deletion and expresses a shortened version of gIII, and of wild-type (wt) virus, to MDBK cells has been shown to occur similarly. To ascertain whether different domains of gIII control the expression of the different biological functions of the gIII protein, we have compared several aspects of virus-host cell interactions of PrV2, of a gIII-null virus, and of wt virus. Our results showed that the deletion of the internal segment of the gIII glycoprotein affects adsorption and virus release differently, i.e. that these two functions of gIII appear to be independent of each other. Furthermore, we observed that although the primary adsorption of PrV2 and wt virus to MDBK cells is similar, PrV2 behaved like a gIII-null mutant with respect to virulence. The apparent contradiction between these two findings was resolved when it was found that although PrV2 binds as well as does wt to some cell types, it binds poorly to other cell types. The functional importance of different domains of gIII in virus adsorption thus differs, depending on the cell type with which the virus interacts.


Assuntos
Regulação Viral da Expressão Gênica , Herpesvirus Suídeo 1/patogenicidade , Pseudorraiva/metabolismo , Proteínas do Envelope Viral/genética , Animais , Células Cultivadas , Galinhas , Herpesvirus Suídeo 1/genética , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos BALB C , Mutagênese , Polilisina/farmacologia , Relação Estrutura-Atividade , Virulência , Replicação Viral/efeitos dos fármacos , Replicação Viral/genética
16.
J Virol ; 66(4): 2316-25, 1992 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-1312633

RESUMO

Mutants of pseudorabies virus defective in either glycoprotein gI or gIII are only slightly less virulent for mice and chickens than is wild-type virus, while mutants defective in both gI and gIII are avirulent. To clarify the reason for the lack of virulence of the gI- gIII- mutants, we have analyzed in some detail the interactions of these mutants with their hosts. The results obtained showed that the gI glycoprotein is an accessory protein that promotes cell fusion. This conclusion is based on the findings that in some cell types, syncytium formation is significantly reduced in mutants deficient in gI. Furthermore, despite efficient replication, gI- mutants form significantly smaller plaques on some cell types. Finally, while wild-type and gI- virus are neutralized similarly by antisera, the size of the plaques formed by gI- mutants, but not by wild-type virus, is reduced by the presence of neutralizing antibodies in the overlay. Passive immunization of mice with neutralizing antipseudorabies virus sera is also considerably more effective in protecting them against challenge with gI- mutants than in protecting them against challenge with wild-type virus. These results show that gI- mutants are deficient in their ability to form syncytia and to spread directly by cell-to-cell transmission and that these mutants spread mainly by adsorption of released virus to uninfected cells. Wild-type virus and gIII- mutants, however, spread mainly via direct cell-to-cell transmission both in vivo and in vitro. We postulate that the lack of virulence of the gIII- gI- virus is attributable to its inability to spread by either mode, the defect in gIII affecting virus spread by adsorption of released virus and the defect in gI affecting cell-to-cell spread. Although a gI- gIII- mutant replicates as well as a gIII- mutant, it will be amplified much less well. Our results with in vitro systems show that this is indeed the case.


Assuntos
Fusão Celular , Herpesvirus Suídeo 1/fisiologia , Proteínas do Envelope Viral/fisiologia , Replicação Viral , Animais , Anticorpos Antivirais/imunologia , Linhagem Celular , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/patogenicidade , Imunização Passiva , Cinética , Camundongos , Mutação , Testes de Neutralização , Pseudorraiva/imunologia , Pseudorraiva/microbiologia , Mapeamento por Restrição , Proteínas do Envelope Viral/genética , Ensaio de Placa Viral , Virulência/genética
17.
J Virol ; 62(7): 2251-7, 1988 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2836609

RESUMO

One of the major glycoproteins of pseudorabies virus, gIII, is nonessential for growth in cell culture. Mutants defective in gIII, however, consistently yield lower titers of infectious virus (3- to 20-fold) than does wild-type virus. The interactions of gIII- mutants with their host cells were compared with those of wild-type virus in an attempt to uncover the functions of gIII. We show that gIII plays a major role in the stable adsorption of the virus to its host cell; in the absence of gIII, the rate of adsorption is reduced and adsorption is easily reversed by washing. Thus, adsorption of pseudorabies virus can be said to occur in at least the following two ways: (i) a gIII-mediated rapid adsorption or (ii) a slower and more labile adsorption that is independent of gIII. After virions have been complexed with monoclonal antibodies against gIII (but not some monoclonal antibodies against other glycoproteins), both modes of adsorption were inhibited. Glycoprotein gIII affects virus stability and virus release, as well as adsorption. The effect on virus release is marked when the virus is defective in additional functions. Thus, although we found no obvious difference in the release of virus from gIII- or wild-type virus-infected rabbit kidney cells, release of a gIII-/gI- double mutant from the cells occurred less readily than did release of a gI- mutant. The gIII-/gI- and gIII- mutants, however, adsorbed to cells at a similar rate, indicating that the effects of gIII on adsorption and virus release constitute separate functions. The Bartha vaccine strain of pseudorabies virus has a defective gIII gene and is released poorly from rabbit kidney cells. After the resident Bartha gIII gene was replaced by the gIII gene of wild-type virus, virus release was enhanced considerably. Since inactivation of gIII in wild-type pseudorabies virus did not significantly affect virus release, the Bartha strain must be defective in another function which, in conjunction with gIII, significantly affects virus release. These results indicate again that gIII affects virus release in conjunction with other functions. Also, although the Bartha strain was functionally defective in virus release, it adsorbed to cells as well as wild-type virus did, showing that the effects of gIII on virus adsorption and release constitute separate functions. We conclude that gIII is a multifunctional glycoprotein.


Assuntos
Herpesvirus Suídeo 1/fisiologia , Proteínas do Envelope Viral/fisiologia , Adsorção , Animais , Bovinos , Linhagem Celular , Efeito Citopatogênico Viral , Fibroblastos/metabolismo , Herpesvirus Suídeo 1/genética , Rim , Coelhos , Suínos , Proteínas do Envelope Viral/genética , Vacinas Virais
18.
J Virol ; 63(12): 5475-7, 1989 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-2555567

RESUMO

The role of the nonessential glycoproteins gI, gp63, and gIII in the release of pseudorabies virus from different cell lines was investigated. We show that these glycoproteins may have a beneficial or deleterious effect on virus release depending on the type of cell in which the virus is grown. Inactivation of the genes encoding either gI, gp63, or gIII has no detectable effect on virus release from rabbit kidney cells. Inactivation of gI or gp63 strongly promotes virus release from chicken embryo fibroblasts, whereas inactivation of gIII reduces virus release from these cells. A defect in both gI and gIII or in both gp63 and gIII diminishes virus release from rabbit kidney cells but improves release from chicken embryo fibroblasts. We demonstrate that all three nonessential glycoproteins contribute to one specific aspect of viral growth, namely, virus release, and that they affect virus release in conjunction with each other. Furthermore, our results show that the manifestation of the role of each of these viral functions in virus growth may differ in different cell types, i.e., that release is affected by these viral functions in conjunction with some unknown cellular function.


Assuntos
Glicoproteínas/fisiologia , Herpesvirus Suídeo 1/fisiologia , Replicação Viral , Animais , Linhagem Celular , Vírus Defeituosos/genética , Vírus Defeituosos/crescimento & desenvolvimento , Vírus Defeituosos/fisiologia , Glicoproteínas/genética , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/crescimento & desenvolvimento , Cinética , Mutação , Fenótipo
19.
J Virol ; 63(8): 3323-9, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-2545907

RESUMO

Adsorption of mutants of pseudorabies virus (PrV) lacking glycoprotein gIII is slower and less efficient than is that of wild-type virus (C. Schreurs, T. C. Mettenleiter, F. Zuckermann, N. Snugg, and T. Ben-Porat, J. Virol. 62:2251-2257, 1988). To ascertain the functions of gIII in the early interactions of PrV with its host cells, we compared the effect on wild-type virus and gIII- mutants of antibodies specific for various PrV proteins. Although adsorption of wild-type virus was inhibited by polyvalent antisera against PrV as well as by sera against gIII and gp50 (but not sera against gII), adsorption of the gIII- mutants was not inhibited by any of these antisera. These results suggest that, in contrast to adsorption of wild-type PrV, the initial interactions of the gIII- mutants with their host cells are not mediated by specific viral proteins. Furthermore, competition experiments showed that wild-type Prv and the gIII- mutants do not compete for attachment to the same cellular components. These findings show that the initial attachment of PrV to its host cells can occur by a least two different modes--one mediated by glycoprotein gIII and the other unspecific. gIII- mutants not only did not adsorb as readily to cells as did wild-type virus but also did not penetrate cells as rapidly as did wild-type virus after having adsorbed. Antibodies against gIII did not inhibit the penetration of adsorbed virus (wild type or gIII-), whereas antibodies against gII and gp50 did. It is unlikely, therefore, that gIII functions directly in virus penetration. Our results support the premises that efficient adsorption of PrV to host cell components is mediated either directly or indirectly by gIII (or a complex of viral proteins for which the presence of gIII is functionally essential) and that this pathway of adsorption promotes the interactions of other viral membrane proteins with the appropriate cellular proteins, leading to the rapid penetration of the virus into the cells. The slower penetration of the gIII- mutants than of wild-type PrV appears to be related to the slower and less efficient alternative mode of adsorption of PrV that occurs in the absence of glycoprotein gIII.


Assuntos
Herpesvirus Suídeo 1/fisiologia , Proteínas do Envelope Viral/fisiologia , Animais , Anticorpos Antivirais/imunologia , Ligação Competitiva , Linhagem Celular , DNA Viral/biossíntese , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/imunologia , Soros Imunes/imunologia , Mutação , Testes de Neutralização , Proteínas do Envelope Viral/genética
20.
J Virol ; 64(1): 278-86, 1990 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-2152816

RESUMO

Glycoprotein gIII is one of the major envelope glycoproteins of pseudorabies virus (PrV) (Suid herpesvirus 1). Although it is dispensable for viral growth, it has been shown to play a prominent role in the attachment of the virus to target cells, since gIII- deletion mutants are severely impaired in adsorption (C. Schreurs, T. C. Mettenleiter, F. Zuckermann, N. Sugg, and T. Ben-Porat, J. Virol. 62:2251-2257, 1988). We show here that during the process of adsorption of PrV, the viral glycoprotein gIII interacts with a cellular heparinlike receptor. This conclusion is based on the following findings. (i) Heparin inhibits plaque formation of PrV by preventing the adsorption of wild-type virions to target cells. However, heparin does not interfere with the plaque formation of PrV mutants that lack glycoprotein gIII. (ii) Wild-type virions readily adsorb to matrix-bound heparin, whereas gIII- mutants do not. (iii) Pretreatment of cells with heparinase reduces considerably the ability of wild-type PrV to adsorb to these cells and to form plaques but does not negatively affect gIII- mutants. (iv) Glycoprotein gIII binds to heparin and appears to do so in conjunction with glycoprotein gII. Although heparin significantly reduces the adsorption of wild-type virus to all cell types tested, quantitative differences in the degree of inhibition of virus adsorption by heparin to different cell types were observed. Different cell types also retain their abilities to adsorb wild-type PrV to a different extent after treatment with heparinase and differ somewhat in their relative abilities to adsorb gIII- mutants. Our results show that while the primary pathway of adsorption of wild-type PrV to cells occurs via the interaction of viral glycoprotein gIII with a cellular heparinlike receptor, an alternative mode of adsorption, which is not dependent on either component, exists. Furthermore, the relative abilities of different cell types to adsorb PrV by the gIII-dependent or the alternative mode vary to some extent.


Assuntos
Heparina/metabolismo , Herpesvirus Suídeo 1/fisiologia , Proteínas do Envelope Viral/metabolismo , Adsorção , Animais , Linhagem Celular , Cromatografia de Afinidade , Heparina Liase , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/isolamento & purificação , Cinética , Mutação , Polissacarídeo-Liases/metabolismo , Proteínas do Envelope Viral/isolamento & purificação , Ensaio de Placa Viral , Proteínas Virais/isolamento & purificação
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