Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 199
Filtrar
1.
Clin Gerontol ; 45(2): 252-271, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-31971092

RESUMEN

Objectives: Large numbers of older Americans have a history of military service, which may be positively or negatively associated with mental health in late life. We reviewed literature with the aim of better understanding the mental health needs of older Veterans.Methods: Articles included those published in 2009-2018 and focused on prevalence/risk for mental illness and suicide among older Veterans; utilization of mental health services; effectiveness of evidence-based behavioral treatments; and pertinent care delivery models.Results: Older Veterans are generally resilient. A significant minority experience mental health concerns that are associated with poor outcomes including a substantial number of suicides. Most published research is based on the approximately one third of Veterans who use the Veterans Health Administration (VHA) for care. Older Veterans with mental health diagnoses are less likely to utilize mental health services compared to younger Veterans, but as likely to benefit once engaged. Integrated care models in primary and geriatric care settings are promising.Conclusions: Aging Veterans are a large subset of Americans whose mental health needs are complex and deserve attention.Clinical Implications: Clinicians should ask about history of military service (i.e., Veteran status) and utilize available resources when providing care for older Veterans.


Asunto(s)
Prevención del Suicidio , Veteranos , Anciano , Envejecimiento , Humanos , Salud Mental , Estados Unidos/epidemiología , United States Department of Veterans Affairs , Veteranos/psicología
3.
Psychol Serv ; 14(1): 13-22, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28134553

RESUMEN

U.S. health systems, policy makers, and patients increasingly demand high-value care that improves health outcomes at lower cost. This study describes the initial design and analysis of the Mental Health Management System (MHMS), a performance data and quality improvement tool used by the Veterans Health Administration (VHA) to increase the value of its mental health care. The MHMS evaluates access to and quality of mental health care, organizational structure and efficiency, implementation of innovative treatment options, and, in collaboration with management, resource needs for delivering care. Performance on 31 measures was calculated for all U.S. VHA facilities (N = 139). Pearson correlations revealed that better access to care was significantly associated with fewer mental health provider staffing vacancies (r = -.24) and higher staff-to-patient ratios for psychiatrists (r = .19) and other outpatient mental health providers (r = .27). Higher staff-to-patient ratios were significantly associated with higher performance on a number of patient and provider satisfaction measures (range of r = .18-.51) and continuity of care measures (range of r = .26-.43). Relationships observed between organizational and clinical performance measures suggest that the MHMS is a robust informatics and quality improvement tool that can serve as a model for health systems planning to adopt a value perspective. Future research should expand the MHMS framework to measure patient and health systems costs and psychosocial outcomes, as well as evaluate whether quality improvement solutions implemented as a result of using organizational information leads to higher-value mental health care. (PsycINFO Database Record


Asunto(s)
Accesibilidad a los Servicios de Salud , Aplicaciones de la Informática Médica , Servicios de Salud Mental , Mejoramiento de la Calidad , United States Department of Veterans Affairs , Accesibilidad a los Servicios de Salud/economía , Accesibilidad a los Servicios de Salud/organización & administración , Accesibilidad a los Servicios de Salud/normas , Humanos , Servicios de Salud Mental/economía , Servicios de Salud Mental/organización & administración , Servicios de Salud Mental/normas , Mejoramiento de la Calidad/economía , Mejoramiento de la Calidad/organización & administración , Mejoramiento de la Calidad/normas , Estados Unidos , United States Department of Veterans Affairs/economía , United States Department of Veterans Affairs/organización & administración , United States Department of Veterans Affairs/normas
4.
Vet Rec ; 163(18): 539-43, 2008 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-18978367

RESUMEN

A Eurasian otter (Lutra lutra) cub found in weak condition on the Isle of Harris, Scotland, developed bilateral corneal oedema 16 days after being admitted to a rehabilitation centre. It died unexpectedly on day 26. On postmortem examination, there was excess clear fluid in the body cavities and the liver was swollen with numerous pale focal lesions and petechial haemorrhages throughout. Histopathological examination revealed bundles of bacilli morphologically typical of Clostridium piliforme within hepatocytes. Comparative analysis of the nucleotide base sequence of a 16S rdna fragment amplified from the infected liver tissue revealed that it was identical to a C piliforme 16S rdna sequence. The possibility of concurrent infection with canine adenovirus type 1 was considered but none of the characteristic histopathological lesions was observed and examination of the liver by transmission electron microscopy was negative for virus particles. This appears to be the first record of Tyzzer's disease in an otter and the first in a wild animal in Britain.


Asunto(s)
Infecciones por Clostridium/veterinaria , Clostridium/patogenicidad , Hígado/microbiología , Hígado/patología , Nutrias/microbiología , Animales , Animales Recién Nacidos , Clostridium/aislamiento & purificación , Infecciones por Clostridium/diagnóstico , Infecciones por Clostridium/patología , ADN Bacteriano/química , Resultado Fatal , Femenino , Inmunohistoquímica/veterinaria , ARN Ribosómico 16S , Escocia
5.
Br J Cancer ; 97(5): 695-9, 2007 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-17653071

RESUMEN

Among 16 541 3-year survivors of childhood cancer in Britain, 39 soft tissue sarcomas (STSs) occurred and 1.1 sarcomas were expected, yielding a standardised incidence ratio (SIR) of 16.1. When retinoblastomas were excluded from the cohort, the SIR for STSs was 15.9, and the cumulative risk of developing a soft tissue tumour after childhood cancer within 20 years of 3-year survival was 0.23%. In the case-control study, there was a significant excess of STSs in those patients exposed to both radiotherapy (RT) and chemotherapy, which was five times that observed among those not exposed (P=0.02). On the basis of individual radiation dosimetry, there was evidence of a strong dose-response effect with a significant increase in the risk of STS with increasing dose of RT (P<0.001). This effect remained significant in a multivariate model. The adjusted risk in patients exposed to RT doses of over 3000 cGy was over 50 times the risk in the unexposed. There was evidence of a dose-response effect with exposure to alkylating agents, the risk increasing substantially with increasing cumulative dose (P=0.05). This effect remained after adjusting for the effect of radiation exposure.


Asunto(s)
Neoplasias/complicaciones , Sarcoma/epidemiología , Estudios de Casos y Controles , Niño , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos , Humanos , Modelos Logísticos , Neoplasias/tratamiento farmacológico , Neoplasias/radioterapia , Radioterapia/efectos adversos , Sistema de Registros/estadística & datos numéricos , Factores de Riesgo , Sarcoma/etiología , Reino Unido/epidemiología
6.
Proc Inst Mech Eng H ; 220(5): 583-96, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16898216

RESUMEN

Total joint replacements (TJRs) have a limited lifetime, but the introduction of components that exhibit good lubricating properties with low friction and low wear could extend the life of TJRs. A novel acetabular cup design using polyurethane (PU) as a compliant layer (to mimic the natural joint) has been developed. This study describes a series of friction tests that have been used to select the most appropriate material, optimize the design parameters, and fine-tune the manufacturing processes of these joints. To determine accurately the mode of lubrication under which these joints operate, a synthetic lubricant was used in all these tests. Friction tests were carried out to assess the lubrication of four PU bearing materials. Corethane 80A was the preferred material and was subjected to subsequent testing. Friction tests conducted on acetabular cups, manufactured using Corethane 80A articulating against standard, commercially available femoral heads, demonstrated friction factors approaching those for full-fluid-film lubrication with only approximately 1 per cent asperity contact. As the joint produces these low friction factors within less than half a walking cycle after prolonged periods of loading, start-up friction was not considered to be a critical factor. Cups performed well across the full range of femoral head sizes, but a number of samples manufactured with reduced radial clearances performed with higher than expected friction. This was caused by the femoral head being gripped around the equator by the low clearance cup. To avoid this, the cup design was modified by increasing the flare at the rim. In addition to this the radial clearance was increased. As the material is incompressible, a radial clearance of 0.08 mm was too small for a cup diameter of 32 mm. A clearance of between 0.10 and 0.25 mm produced a performance approaching full-fluid-film lubrication. This series of tests acted as a step towards the optimization of the design of these joints, which has now led to an in vivo ovine model.


Asunto(s)
Acetábulo/fisiología , Acetábulo/cirugía , Materiales Biomiméticos , Biomimética/instrumentación , Prótesis de Cadera , Líquido Sinovial/fisiología , Materiales Biocompatibles/química , Biomimética/métodos , Simulación por Computador , Diseño Asistido por Computadora , Elasticidad , Análisis de Falla de Equipo , Fricción , Articulación de la Cadera/fisiología , Articulación de la Cadera/cirugía , Humanos , Lubrificación , Ensayo de Materiales , Modelos Biológicos , Diseño de Prótesis , Estrés Mecánico , Torque
7.
Epidemiol Infect ; 133(5): 915-25, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16181514

RESUMEN

The prevalence of specific HSV-2 antibodies was studied in Tanzanian and Norwegian sexually transmitted disease (STD) patients (1095) and non-STD patients (488). Correlates to demographic and behavioural factors were evaluated. Seropositivity was determined by the non-commercial peptide-55 enzyme-linked immunoassay. The prevalence of HSV-2 antibodies was 70% in Tanzanian and 17% in Norwegian STD patients, 35% in Tanzanian blood donors and pregnant women, and 4, 7 and 14% in Norwegian medical students, blood donors and pregnant women respectively. A higher HSV-2 prevalence was associated with female sex, increasing age, previous STDs, history of genital HSV infection, coitarchal age (age at first intercourse) <15 years and HIV seropositivity. Compared to previous data, the prevalence of HSV-2 antibodies in Tanzanian STD patients has increased remarkably. In Norwegian STD patients our results are consistent with, or lower than, the prevalence previously reported in Western Europe. Demographic rather than behavioural factors were associated with higher prevalence of HSV-2 antibodies in STD patients.


Asunto(s)
Herpes Simple/epidemiología , Herpesvirus Humano 2/inmunología , Adolescente , Adulto , Anticuerpos Antivirales/análisis , Donantes de Sangre/estadística & datos numéricos , Ensayo de Inmunoadsorción Enzimática , Femenino , Herpes Simple/sangre , Herpes Simple/etiología , Herpesvirus Humano 2/aislamiento & purificación , Humanos , Noruega/epidemiología , Embarazo , Complicaciones Infecciosas del Embarazo/sangre , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/etiología , Prevalencia , Factores de Riesgo , Enfermedades de Transmisión Sexual/sangre , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/etiología , Estudiantes de Medicina/estadística & datos numéricos , Tanzanía/epidemiología
8.
J Clin Oncol ; 23(12): 2618-28, 2005 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-15728225

RESUMEN

PURPOSE: To improve outcome for children with nonmetastatic rhabdomyosarcoma and to reduce systematic use of local therapy. PATIENTS AND METHODS: Five hundred three previously untreated patients aged from birth to 18 years, recruited between 1989 and 1995, were allocated to one of six treatment schedules by site and stage. RESULTS: Five-year overall survival (OS) and event-free survival (EFS) were 71% and 57%, respectively. Primary site, T-stage, and pathologic subtype were independent factors in predicting OS by multivariate analysis. Differences between EFS and OS reflected local treatment strategy and successful re-treatment for some patients after relapse. Patients with genitourinary nonbladder prostate tumors had the most favorable outcome (5-year OS, 94%): the majority were boys with paratesticular tumors treated successfully without alkylating agents. Patients with stage III disease treated with a novel six-drug combination showed improved survival compared with the Malignant Mesenchymal Tumor 84 study (MMT 84; 5-year OS, 60% v 42%, respectively). OS was not significantly better than that achieved in the previous MMT 84 study, but 49% of survivors were cured without significant local therapy. CONCLUSION: Selective avoidance of local therapy is justified in some patients, though further work is required to prospectively identify those for whom this is most applicable. Exclusion of alkylating agents is justified for the most favorable subset of patients. The value of the new six-drug chemotherapy combination is being evaluated further in a randomized study (MMT 95).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Rabdomiosarcoma/tratamiento farmacológico , Rabdomiosarcoma/patología , Adolescente , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Carboplatino/administración & dosificación , Niño , Preescolar , Dactinomicina/administración & dosificación , Supervivencia sin Enfermedad , Esquema de Medicación , Epirrubicina/administración & dosificación , Etopósido/administración & dosificación , Femenino , Humanos , Ifosfamida/administración & dosificación , Lactante , Recién Nacido , Masculino , Análisis Multivariante , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Pronóstico , Tenipósido/administración & dosificación , Resultado del Tratamiento , Vincristina/administración & dosificación
9.
Br J Cancer ; 91(11): 1905-10, 2004 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-15534607

RESUMEN

In a population-based, retrospective cohort study of 16 541 3-year survivors of childhood cancer treated in Britain up to the end of 1987, 278 second malignant neoplasms (SMNs) were identified against 39.4 expected giving a standardised incidence ratio (SIR) of 6.2. The overall cumulative risk of an SMN by 25 years from 3-year survival from childhood cancer was 4.2%. Analysis of the cohort of nonretinoblastoma childhood cancers combined revealed a significant decline in SIR of SMN with increasing duration of follow-up. There was a greater risk of developing a SMN, particularly secondary acute myeloid leukaemia, in those diagnosed with childhood cancer from 1980 onwards. However, on multivariate modeling, this was not an independent risk factor. There was significant heterogeneity (P<0.001) in SIR of SMN across different treatment groups, the greatest risk observed in the group exposed to both radiotherapy and chemotherapy. The risks of SMN observed were comparable with those in other population-based studies. While the decline in SIR with duration of follow-up and the small excess numbers of cancers observed over later decades after diagnosis are reassuring, the high excess risk, particularly of leukaemia, associated with recent more intense therapy is of concern.


Asunto(s)
Genética de Población , Leucemia Mieloide/etiología , Neoplasias Primarias Secundarias/epidemiología , Enfermedad Aguda , Adolescente , Niño , Preescolar , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Factores de Riesgo , Sobrevivientes , Factores de Tiempo , Reino Unido/epidemiología
10.
Pediatr Blood Cancer ; 42(4): 311-9, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-14966826

RESUMEN

BACKGROUND: The aims of UKWT2 included consolidating the results for stage III patients obtained in UKWT1 and improving the outcome for patients with inoperable tumours by giving vincristine, actinomycin-D and doxorubicin in an intensive schedule (Intensive AVA). PROCEDURE: The second UK WT trial (UKWT2) ran between July 1986 and September 1991 accruing 448 patients. One hundred and six patients were diagnosed and treated for stage III disease. Six had clear cell sarcoma of the kidney (CCSK) and seven had rhabdoid tumours of the kidney (RTK) and are analysed separately. One other patient was excluded from overall analysis. Ninety-two patients were followed for a median of 115 months. Seventy-five received standard chemotherapy and abdominal radiotherapy according to protocol. Seventeen had stage III disease at immediate nephrectomy, but radiotherapy was omitted by physician choice. Thirty-three patients had inoperable disease at diagnosis and received pre-nephrectomy chemotherapy. RESULTS: Overall survival (OS) at 4 years for stage III favourable histology (FH) patients receiving abdominal RT was 83% (CI: 73-89). For children with stage III disease in whom RT was omitted the OS was 82% (CI: 59-97) and for inoperable disease 94% (CI: 78-98). The overall and event-free survival (EFS) of children with stage III CCSK was 100% and was achieved with the majority of patients not receiving radiotherapy (CI: 48-100). Three of seven children with RTK are alive EFS and OS 43% (CI: 10-73). For patients treated by abdominal radiotherapy the overall local control rate was 94.4% (CI: 86.4-98.5*%), 96.7% (CI: 88.5-99.6%) for flank RT and 83.3% (51.6-98.0%) for whole abdominal radiotherapy (WRT). CONCLUSIONS: The outcome for stage III FH disease was similar to that reported for UKWT1 and NWTS-3. The combination of abdominal RT together with 3-drug chemotherapy achieves a high abdominal tumour control rate. Flank RT is probably sufficient for localised tumour rupture. The high cure rates for children in this trial with 'inoperable disease' suggests that treatment should be modified according to their post-chemotherapy stage in order to avoid over-treatment. The high OS for stage III CCSK on this protocol suggests that treatment duration could be curtailed and the role of RT reviewed, though the numbers are small. The prognosis for older children with RTK seems to be better than for younger children although larger studies are required to confirm this.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Renales/tratamiento farmacológico , Tumor de Wilms/tratamiento farmacológico , Adolescente , Niño , Dactinomicina/uso terapéutico , Doxorrubicina/uso terapéutico , Humanos , Neoplasias Renales/mortalidad , Neoplasias Renales/radioterapia , Radioterapia Adyuvante , Sarcoma de Células Claras/tratamiento farmacológico , Sarcoma de Células Claras/mortalidad , Sarcoma de Células Claras/radioterapia , Análisis de Supervivencia , Resultado del Tratamiento , Reino Unido , Vincristina/uso terapéutico , Tumor de Wilms/mortalidad , Tumor de Wilms/radioterapia
11.
Clin Rehabil ; 16(3): 329-37, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12017520

RESUMEN

OBJECTIVE: To determine whether transferring equipment designed to assist a carer when moving someone who is able to take some weight through their legs is likely to affect the risk of back problems in the carer. DESIGN: Twelve pieces of equipment were tested by nurses transferring patients from commode to wheelchair and vice versa, and from wheelchair to bed and vice versa. Video recordings were taken of each transfer and freeze-frame pictures at the moment of greatest load were analysed. Compressive disc force was deduced, using a biomechanical model, from the weights of the patient and nurse and measurements of anatomical distances and angles. SETTING: The Sir Walter Puckey Gait Laboratory, in the Rehabilitation Research Unit, University of Southampton. SUBJECTS: Six female trained nurses with no recent history of hernia, back pain or pregnancy during the previous six months were recruited to use the equipment. Two female patients were chosen from those volunteering and screened for stroke, confusion and unusual footwear. The patients were able to partially weight-bear and were used to being transferred. RESULTS: The results indicate that the critical value of 3.4 kN at the L5/S1 disc (specified by the US National Institute for Occupational Safety and Health) was not exceeded when using transferring equipment. CONCLUSION: In this study, loading on the spine during transferring tasks with or without equipment was not considered harmful when good technique was employed.


Asunto(s)
Traumatismos de la Espalda/prevención & control , Equipos y Suministros , Elevación , Enfermeras y Enfermeros , Transporte de Pacientes/métodos , Traumatismos de la Espalda/etiología , Fenómenos Biomecánicos , Femenino , Humanos , Disco Intervertebral/fisiología , Elevación/efectos adversos , Vértebras Lumbares
12.
Virology ; 273(1): 139-48, 2000 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-10891416

RESUMEN

The herpes simplex virus type 1 DNA polymerase consists of a catalytic subunit (POL or UL30) and a processivity factor (UL42). The POL/UL42 interaction, which occurs through the extreme C-terminus of POL, is essential for HSV-1 replication and thus represents a valid target for drug inhibition. We recently showed (A. Loregian et al. (1999) Proc. Natl. Acad. Sci. USA 96, 5221-5226) that an oligopeptide corresponding to the 27 C-terminal amino acids of POL, when delivered into herpes simplex virus type 1-infected cells by a protein carrier, was able to localize into the nucleus and to inhibit viral replication by disruption of the POL/UL42 interaction. In this report, to further characterize the 27 mer (Pol peptide), we investigated whether its nuclear localization was due to the presence of a nuclear localization signal. By testing the ability of the Pol peptide to localize the beta-galactosidase, a normally cytoplasmic protein, to the nucleus, we confirmed that the Pol peptide contained a functional nuclear localization signal, corresponding to the RRMLHR motif. This sequence proved not only necessary but also sufficient for nuclear localization, because its substitution with a six-alanine stretch prevented nuclear translocation of the beta-galactosidase-Pol peptide fusion. Site-directed mutagenesis experiments on this revealed that both the three basic arginines and the two hydrophobic residues Met and Leu were crucial for nuclear targeting. Finally, functionally equivalent sequences were also found in the C-terminus of the catalytic subunits of human cytomegalovirus (RRLHL) and of equine herpesvirus-1 DNA polymerase (RRILH).


Asunto(s)
Dominio Catalítico , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/metabolismo , Exodesoxirribonucleasas/química , Exodesoxirribonucleasas/metabolismo , Herpesvirus Humano 1/enzimología , Señales de Localización Nuclear , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Transporte Biológico , Núcleo Celular/metabolismo , Chlorocebus aethiops , Citomegalovirus/enzimología , Citoplasma/metabolismo , ADN Polimerasa Dirigida por ADN/genética , Exodesoxirribonucleasas/genética , Técnica del Anticuerpo Fluorescente Indirecta , Herpesvirus Équido 1/enzimología , Datos de Secuencia Molecular , Mutación/genética , Señales de Localización Nuclear/genética , Señales de Localización Nuclear/fisiología , Unión Proteica , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transfección , Células Vero , beta-Galactosidasa/genética , beta-Galactosidasa/metabolismo
13.
J Virol Methods ; 87(1-2): 63-70, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10856753

RESUMEN

Glycoprotein G of HSV-2 (gG2) and a peptide, corresponding to a previously recognised immunodominant epitope spanning residues 561-578 of the protein, were compared directly for type-specific serodiagnosis of HSV-2. The protein was affinity purified and obtained in a commercially available EIA kit while the peptide, previously designated as peptide 55, was made as a multiple antigenic peptide. A panel of 100 characterised serum samples (60 HSV-2 positive, 20 HSV-1 positive and 20 HSV negative) was screened using the two antigens. The intact protein and peptide 55 showed the same sensitivity for antibodies in the serum of HSV-2 infected individuals, reacting with 96.7% (58/60) of the samples. The peptide did not react with any of the HSV-1 positive or HSV negative sera. In contrast, gG2 gave a number of false positive results, reacting with 20% (4/20) of the HSV-1 positive sera and 10% (2/20) of the HSV negative sera. The superior performance of peptide 55, together with the very much lower costs of its production, compared with gG2 suggest that the peptide will become the antigen of choice in enzyme immunoassays for type-specific serodiagnosis of HSV-2.


Asunto(s)
Anticuerpos Antivirales/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Herpesvirus Humano 2/inmunología , Inmunoglobulina G/sangre , Antígenos Virales/inmunología , Reacciones Cruzadas/inmunología , Reacciones Falso Positivas , Glicoproteínas/inmunología , Herpes Simple/virología , Humanos , Epítopos Inmunodominantes/inmunología , Sensibilidad y Especificidad , Pruebas Serológicas
14.
Proc Natl Acad Sci U S A ; 96(9): 5221-6, 1999 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-10220447

RESUMEN

We report an intracellular peptide delivery system capable of targeting specific cellular compartments. In the model system we constructed a chimeric protein consisting of the nontoxic B subunit of Escherichia coli heat-labile enterotoxin (EtxB) fused to a 27-mer peptide derived from the DNA polymerase of herpes simplex virus 1. Viral DNA synthesis takes places in the nucleus and requires the interaction with an accessory factor, UL42, encoded by the virus. The peptide, designated Pol, is able to dissociate this interaction. The chimeric protein, EtxB-Pol, retained the functional properties of both EtxB and peptide components and was shown to inhibit viral DNA polymerase activity in vitro via disruption of the polymerase-UL42 complex. When added to virally infected cells, EtxB-Pol had no effect on adenovirus replication but specifically interfered with herpes simplex virus 1 replication. Further studies showed that the antiviral peptide localized in the nucleus, whereas the EtxB component remained associated with vesicular compartments. The results indicate that the chimeric protein entered through endosomal acidic compartments and that the Pol peptide was cleaved from the chimeric protein before being translocated into the nucleus. The system we describe is suitable for delivery of peptides that specifically disrupt protein-protein interactions and may be developed to target specific cellular compartments.


Asunto(s)
Antivirales/farmacología , Toxinas Bacterianas/genética , Toxinas Bacterianas/farmacología , ADN Polimerasa Dirigida por ADN/genética , ADN Polimerasa Dirigida por ADN/farmacología , Sistemas de Liberación de Medicamentos , Enterotoxinas/genética , Enterotoxinas/farmacología , Proteínas de Escherichia coli , Herpesvirus Humano 1/fisiología , Proteínas Recombinantes de Fusión/farmacología , Células 3T3 , Secuencia de Aminoácidos , Animales , Células COS , Chlorocebus aethiops , Escherichia coli , Herpes Simple/tratamiento farmacológico , Herpesvirus Humano 1/efectos de los fármacos , Ratones , Datos de Secuencia Molecular , Proteínas Recombinantes de Fusión/genética , Células Vero , Replicación Viral/efectos de los fármacos
15.
J Med Virol ; 56(1): 79-84, 1998 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9700637

RESUMEN

A series of 67 oligopeptides that spanned the open reading frame of herpes simplex virus type 2 (HSV-2) glycoprotein G (gG2) were synthesized and tested for reactivity with 173 serum specimens collected from 117 individuals. The oligopeptides were made as multiple antigenic peptides consisting of four copies of a unique sequence attached to a branched lysine core and separated from the core by four glycine residues. The sera included HSV antibody-negative samples as well as sera from individuals from whom HSV had been isolated. Isolated viruses were typed by indirect fluorescence using a panel of type-specific monoclonal antibodies. One peptide, corresponding to residues 561 to 578 of gG2, did not react with any sera lacking HSV-specific antibodies of with sera from HSV-1-infected individuals, but did react with sera from HSV-2-infected individuals. For sera taken seven or more days after initialclinical lesions, the detection rate of the peptide was 92% (47/51), comparable with the 98% (50/51) of truncated glycoprotein D, a sensitive type-common reagent. We conclude that this peptide, of structure (PEEFEGAGDGEPPEDDDSG4)K3A, is an immunodominant type-specific epitope for human antibodies and should be useful for type-specific serodiagnosis of HSV-2. Surprisingly, the epitope lies within one of the most conserved regions of gG1 and gG2. The test can distinguish an initial HSV-2 infection in the presence of a preexisting HSV-1 infection.


Asunto(s)
Herpes Genital/diagnóstico , Herpesvirus Humano 2/inmunología , Epítopos Inmunodominantes/inmunología , Proteínas del Envoltorio Viral/inmunología , Ensayo de Inmunoadsorción Enzimática , Herpes Genital/inmunología , Herpes Genital/virología , Herpesvirus Humano 1/inmunología , Humanos
16.
J Gen Virol ; 79 ( Pt 7): 1603-11, 1998 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9680121

RESUMEN

The UL4 gene of herpes simplex virus type 1 is predicted to encode a 21.5 kDa protein of 199 amino acids. Although UL4 is dispensable for growth in cell culture, its function is not known. In the present study, the promoter of UL4 was examined and found to contain a cAMP-response element which bound the transcription factor CREB, and was strongly activated by cAMP. A recombinant virus, termed UL4HS, was constructed with a nonsense linker inserted into the UL4 open reading frame, to make a truncated UL4 protein of 60 amino acids. In addition, a marker-rescued virus, UL4HSMR, was constructed. Western immunoblot analysis revealed a 23 kDa band in extracts of wild-type and marker-rescued virus infected cells which was missing for UL4HS. Only modest differences were observed in the abilities of wild-type and UL4-mutant viruses to grow in Vero cells or in contact-inhibited mouse C3H/10T1/2 cells. In addition, there were only modest differences between the ability of UL4HS to replicate in murine corneas and trigeminal ganglia relative to wild-type viruses, and reactivation of UL4HS from latency was unaffected. Taken together, these data demonstrate that UL4 is dispensable for latency and pathogenesis in mice.


Asunto(s)
Herpesvirus Humano 1/fisiología , Proteínas Virales/genética , Latencia del Virus , Secuencia de Aminoácidos , Animales , Células Cultivadas , Chlorocebus aethiops , AMP Cíclico/metabolismo , Herpesvirus Humano 1/genética , Herpesvirus Humano 1/crecimiento & desarrollo , Humanos , Cinética , Ratones , Ratones Endogámicos C3H , Datos de Secuencia Molecular , Mutagénesis , Células PC12 , Regiones Promotoras Genéticas , Ratas , Recombinación Genética , Células Vero , Proteínas Virales/fisiología , Activación Viral , Replicación Viral
17.
J Gen Virol ; 79 ( Pt 12): 3033-8, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9880019

RESUMEN

Herpes simplex virus type 1 gene UL4 is predicted to encode a 199-amino-acid protein with a molecular mass of 21 5 kDa. We report here identification of this protein and its localization in the nuclei of infected cells. Antisera raised against oligopeptides corresponding to the C terminus of the predicted UL4 protein were used for identification of a 25 kDa protein as the product of the UL4 gene. This protein was not detected in cells infected with a UL4 defective mutant virus, but was synthesized by coupled in vitro transcription-translation of the UL4 gene. Synthesis of the 25 kDa protein was blocked by phosphonoacetic acid, an inhibitor of DNA synthesis, indicating that the UL4 gene is expressed with gamma kinetics. Subcellular fractionation showed the protein to be localized in the nucleus. It was not detected in virions or light particles.


Asunto(s)
AMP Cíclico/metabolismo , Herpesvirus Humano 1/metabolismo , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , AMP Cíclico/genética , Herpesvirus Humano 1/genética , Humanos , Datos de Secuencia Molecular , Proteínas Virales/genética
18.
J Virol ; 71(9): 6390-7, 1997 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-9261356

RESUMEN

The herpes simplex virus type 1 (HSV-1) UL8 DNA replication protein is a component of a trimeric helicase-primase complex. Sixteen UL8-specific monoclonal antibodies (MAbs) were isolated and characterized. In initial immunoprecipitation experiments, one of these, MAb 804, was shown to coprecipitate POL, the catalytic subunit of the HSV-1 DNA polymerase, from extracts of insect cells infected with recombinant baculoviruses expressing the POL and UL8 proteins. Coprecipitation of POL was dependent on the presence of UL8 protein. Rapid enzyme-linked immunosorbent assays (ELISAs), in which one protein was bound to microtiter wells and binding of the other protein was detected with a UL8- or POL-specific MAb, were developed to investigate further the interaction between the two proteins. When tested in the ELISAs, five of the UL8-specific MAbs consistently inhibited the interaction, raising the possibility that these antibodies act by binding to epitopes at or near a site(s) on UL8 involved in its interaction with POL. The epitopes recognized by four of the inhibitory MAbs were approximately located by using a series of truncated UL8 proteins expressed in mammalian cells. Three of these MAbs recognized an epitope near the C terminus of UL8, which was subjected to fine mapping with a series of overlapping peptides. The C-terminal peptides were then tested in the ELISA for their ability to inhibit the POL-UL8 interaction: the most potent exhibited a 50% inhibitory concentration of approximately 5 microM. Our findings suggest that the UL8 protein may be involved in recruiting HSV-1 DNA polymerase into the viral DNA replication complex and also identify a potential new target for antiviral therapy.


Asunto(s)
ADN Helicasas/metabolismo , ADN Polimerasa Dirigida por ADN/metabolismo , Exodesoxirribonucleasas/metabolismo , Herpesvirus Humano 1/enzimología , Proteínas Virales/metabolismo , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/inmunología , Catálisis , Línea Celular , ADN Helicasas/antagonistas & inhibidores , ADN Helicasas/genética , ADN Primasa , ADN Polimerasa Dirigida por ADN/genética , Ensayo de Inmunoadsorción Enzimática , Mapeo Epitopo , Exodesoxirribonucleasas/antagonistas & inhibidores , Exodesoxirribonucleasas/genética , Herpesvirus Humano 1/genética , Humanos , Datos de Secuencia Molecular , Inhibidores de la Síntesis del Ácido Nucleico , Péptidos/metabolismo , Péptidos/farmacología , Pruebas de Precipitina , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Spodoptera/citología , Proteínas Virales/genética
19.
Br J Cancer ; 75(8): 1156-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9099964

RESUMEN

A retrospective histopathological review of 2104 cases of solid tumour was carried out to assess the variability in diagnosis of childhood cancer. Cases were subject to three independent, concurrent opinions from a national panel of specialist pathologists. The conformity between them was analysed using the percentage of agreement and the kappa statistic (kappa), a measure of the level of agreement beyond that which could occur by chance alone, and weighted kappa (w kappa), which demonstrates the degree of variation between opinions. The major groupings of the Birch-Marsden classification were used within which tumours were assigned for kappa analysis according to the clinical significance of the differential diagnoses. The mean agreement for all tumours together was 90%; kappa = 0.82, w kappa = 0.82. Retinoblastoma achieved the highest kappa value (1.0) and lymphoma the lowest (0.66). Of the cases, 16.5% had their original diagnoses amended and the panel confirmed the original diagnosis of paediatric pathologists in 89% of cases compared with 78% for general pathologists. The varying levels of agreement between experts confirm the difficulty of diagnosis in some tumour types, suggesting justification for specialist review in most diagnoses. Specialist training in paediatric pathology is also recommended.


Asunto(s)
Medicina , Neoplasias/diagnóstico , Patología Quirúrgica , Especialización , Niño , Humanos , Reproducibilidad de los Resultados , Estudios Retrospectivos
20.
Protein Expr Purif ; 8(3): 381-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8936601

RESUMEN

The nontoxic B subunit of Escherichia coli heat-labile enterotoxin (EtxB) is a convenient carrier molecule for the attachment and delivery of heterologous peptides into eukaryotic cells. To evaluate the properties of such EtxB-based fusion proteins an efficient method for their production and purification is required. High-level production and purification of native EtxB has been achieved using heterologous expression and secretion in a marine Vibrio (Amin, T., and Hirst, T. R., 1994, Protein Expression Purif. 5, 198-204). However, the use of this method to isolate EtxB fusion proteins has been precluded because of their susceptibility to degradation by extracellular proteases secreted by members of the Vibrionaceae. In this paper a method is described for production of EtxB-pol, comprising the enterotoxin B subunit linked to a 27-residue C-terminal fragment of Pol, the catalytic subunit of DNA polymerase of herpes simplex virus type 1 (HSV-1). Following assessment of the relative efficacy of different Vibrio strains as hosts for EtxB-pol expression, the chimera was produced at the highest level of 3.5 mg/liter by cultures of Vibrio sp.60. Addition of 0.3 mM EDTA to the growth medium blocked proteolysis of the secreted EtxB-pol fusion protein, which was then purified to homogeneity using ammonium sulfate fractionation and hydrophobic interaction chromatography, with a yield of 57%. Purified EtxB-pol reacted with both anti-EtxB and anti-Pol peptide antibodies, and was able to specifically bind UL42, a processivity factor which normally binds to the C-terminal region of HSV-1 Pol. This modified method for expression and purification of EtxB-pol should be of general utility for the preparation of other EtxB-based fusion proteins.


Asunto(s)
Toxinas Bacterianas/genética , ADN Polimerasa Dirigida por ADN/genética , Enterotoxinas/genética , Proteínas de Escherichia coli , Escherichia coli/metabolismo , Exodesoxirribonucleasas/genética , Vibrio/metabolismo , Toxinas Bacterianas/química , Medios de Cultivo , ADN Polimerasa Dirigida por ADN/química , Ácido Edético , Enterotoxinas/química , Exodesoxirribonucleasas/química , Gangliósido G(M1)/química , Productos del Gen pol/química , Herpesvirus Humano 1/enzimología , Unión Proteica , Proteínas Recombinantes de Fusión/biosíntesis , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/aislamiento & purificación , Vibrio/genética , Vibrio cholerae/genética , Vibrio cholerae/metabolismo , Proteínas Virales/química
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...