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1.
HIV Med ; 22(8): 770-774, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-33964099

RESUMO

OBJECTIVES: Rapid initiation of antiretroviral therapy (ART) is important for individuals with high baseline viral loads, such as in primary HIV-1 infection (PHI). Four-drug regimens are sometimes considered; however, data are lacking on tolerability. We aimed to evaluate the tolerability of four-drug regimens used in the Research in Viral Eradication of HIV-1 Reservoirs (RIVER) study. METHODS: At enrolment, ART-naïve adult participants or those newly commenced on ART were initiated or intensified to four-drug regimens within 4 weeks of PHI. Rapid start was defined as pre-confirmation or ≤ 7 days of confirmed diagnosis. Primary and secondary outcomes were patient-reported adherence measured by 7-day recall and regimen switches between enrolment and randomization, respectively. RESULTS: Overall, 54 men were included: 72.2% were of white ethnicity, with a median age of 32 years old, 42.6% had a viral load of ≥ 100 000 HIV-1 RNA copies/mL, and in 92.6% sex with men was the mode of acquisition of HIV-1. Twenty (37%) started a four-drug regimen and 34 (63%) were intensified. Rapid ART initiation occurred in 28%, 100% started in ≤ 4 weeks. By weeks 4, 12, and 24, 37.0%, 69.0%, and 94.0% were undetectable (viral load < 50 copies/mL), respectively. Adherence rates of 100% at weeks 4, 12, 22 and 24 were reported in 88.9%, 87.0%, 82.4% and 94.1% of participants, respectively. Five individuals switched to three drugs, four changed their regimen constituents, and two switched post-randomization. CONCLUSIONS: Overall, four-drug regimens were well tolerated and had high levels of adherence. Whilst their benefit over three-drug regimens is lacking, our findings should provide reassurance if a temporarily intensified regimen is clinically indicated to help facilitate treatment.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Adulto , Fármacos Anti-HIV/efeitos adversos , Antirretrovirais/efeitos adversos , Quimioterapia Combinada , Infecções por HIV/tratamento farmacológico , Humanos , Masculino , Carga Viral
2.
Phys Med Biol ; 50(12): 2739-48, 2005 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-15930599

RESUMO

This addendum to the code of practice for the determination of absorbed dose for x-rays below 300 kV has recently been approved by the IPEM and introduces three main changes: (i) Due to a lack of available data the original code recommended a value of unity for k(ch) in the very-low-energy range (0.035-1.0 mm Al HVL). A single table of k(ch) values, ranging from 1.01 to 1.07, applicable to both designated chamber types is now presented. (ii) For medium-energy x-rays (0.5-4 mm Cu HVL) methods are given to determine the absorbed dose to water either at 2 cm depth or at the surface of a phantom depending on clinical needs. Determination of the dose at the phantom surface is derived from an in-air measurement and by extending the low-energy range up to 4 mm Cu HVL. Relevant backscatter factors and ratios of mass energy absorption coefficients are given in the addendum. (iii) Relative dosimetry: although not normally forming part of a dosimetry code of practice a brief review of the current literature on this topic has been added as an appendix. This encompasses advice on techniques for measuring depth doses, applicator factors for small field sizes, dose fall off with increasing SSD and choice of appropriate phantom materials and ionization chambers.


Assuntos
Dosagem Radioterapêutica , Radioterapia/métodos , Humanos , Imagens de Fantasmas , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/métodos , Espalhamento de Radiação , Raios X
5.
Emerg Infect Dis ; 7(4): 621-5, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11585522

RESUMO

As part of an investigation of an encephalitis outbreak in New York City, we sampled 430 birds, representing 18 species in four orders, during September 13-23, 1999, in Queens and surrounding counties. Overall, 33% were positive for West Nile (WN) virus-neutralizing antibodies, and 0.5% were positive for St. Louis encephalitis virus-neutralizing antibodies. By county, Queens had the most seropositive birds for WN virus (50%); species with the greatest seropositivity for WN virus (sample sizes were at least six) were Domestic Goose, Domestic Chicken, House Sparrow, Canada Goose, and Rock Dove. One sampled bird, a captive adult Domestic Goose, showed signs of illness; WN virus infection was confirmed. Our results support the concept that chickens and House Sparrows are good arbovirus sentinels. This study also implicates the House Sparrow as an important vertebrate reservoir host.


Assuntos
Doenças das Aves/epidemiologia , Aves/virologia , Surtos de Doenças , Reservatórios de Doenças/veterinária , Aves Canoras/virologia , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Anticorpos Antivirais/sangue , Doenças das Aves/sangue , Doenças das Aves/imunologia , Doenças das Aves/virologia , Aves/sangue , Aves/imunologia , Reações Cruzadas , Vírus da Encefalite de St. Louis/imunologia , Gansos/virologia , Masculino , Testes de Neutralização , Cidade de Nova Iorque/epidemiologia , Estudos Soroepidemiológicos , Aves Canoras/sangue , Aves Canoras/imunologia , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/epidemiologia , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/imunologia
6.
Cancer Immunol Immunother ; 50(5): 241-50, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11499807

RESUMO

A single-chain antibody fragment (scFv) of the humanised monoclonal antibody, hu3S193, that reacts specifically with Le(y) antigen expressed in numerous human epithelial carcinomas was constructed. A five-residue linker joined the C-terminus of the V(H) and the N-terminus of the V(L), which prevented V-domain association into a monomeric scFv and instead directed non-covalent association of two scFvs into a dimer or diabody. The diabody was secreted into the E. coli periplasm using a heat-inducible vector, pPOW3, and recovered as a soluble, correctly processed protein, following osmotic shock or solubilised with 4 M urea from the insoluble fraction. The diabody from both fractions was isolated by a rapid batch affinity chromatography procedure, using the FLAG affinity tag to minimise degradation and aggregation. The purified diabody has an Mr of approximately 54 kDa, was stable and demonstrated similar binding activity as the parent monoclonal antibody, as measured by FACS and BIAcore analyses. The radiolabelled diabody showed a rapid tumour uptake, with fast blood clearance, proving it to be an excellent potential candidate as a tumour-imaging agent.


Assuntos
Anticorpos Monoclonais/genética , Anticorpos Monoclonais/imunologia , Carcinoma/terapia , Antígenos do Grupo Sanguíneo de Lewis/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/farmacocinética , Antígenos de Neoplasias/imunologia , Técnicas Biossensoriais , Carcinoma/metabolismo , Escherichia coli/genética , Citometria de Fluxo , Vetores Genéticos , Temperatura Alta , Humanos , Região Variável de Imunoglobulina/genética , Região Variável de Imunoglobulina/imunologia , Cinética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Dados de Sequência Molecular , Células Tumorais Cultivadas
7.
Am J Cardiol ; 85(5): 630-5, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11078279

RESUMO

A prospective study of 3-dimensional (3-D) transthoracic echocardiographic definition of atrioventricular septal defect (AVSD) morphology and its dynamic changes during the cardiac cycle was performed. The information obtained from 2-D and 3-D transthoracic echocardiography (TTE) was compared with intraoperative findings in an unselected group of 15 patients with AVSD (median age 22 months). In all study patients, 3-D reconstructions provided anatomic views of the atrioventricular valve(s) en face from either atrial or ventricular perspectives that allowed comprehensive assessment of dynamic valve morphology and the mechanism of valve reflux. Left-sided valve function was correctly assessed by 2-D TTE in 11 of 15 patients (73%) and in 14 of 15 (93%) by 3-D TTE. In 6 of 15 patients (40%), the severity of right-sided valve reflux was described precisely by 2-D TTE and in 12 of 15 patients (80%) by 3-D TTE. Additionally, 3-D TTE supplemented the diagnostic information to that available from 2-D TTE on atrial and ventricular septal defects. Although primum atrial septal defects were depicted by 2-D and 3-D TTE in all 15 patients, the description of defect size was more precise by the 3-D TTE (80% vs. 100%, respectively). The presence of secundum atrial septal defect was correctly diagnosed by both TTE techniques in 10 of 15 patients. Disagreement regarding the size of the defect was present only in 2 of 10 patients by 2-D TTE. In another 2 patients, 3-D TTE described multiple defect fenestrations that were missed by 2-D TTE. Thus, the agreement score was 73% for 2-D and 100% for 3-D echo. The agreement for the presence and sizing of ventricular septal defects was 67% for 2-D and 93% for 3-D echo. We conclude that 3-D TTE provided accurate anatomic reconstructions of the common atrioventricular junction and that the use of dynamic 3-D TTE enhanced the anatomic diagnostic capability of standard 2-D TTE. Medica, Inc.


Assuntos
Ecocardiografia Tridimensional , Comunicação Interatrial/diagnóstico por imagem , Comunicação Interventricular/diagnóstico por imagem , Ecocardiografia , Feminino , Comunicação Interatrial/cirurgia , Comunicação Interventricular/cirurgia , Humanos , Lactente , Masculino , Estudos Prospectivos
8.
Crit Care Med ; 28(7): 2259-67, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10921550

RESUMO

OBJECTIVE: To determine whether four stages of weaning (acute, prewean, wean, and outcome) could be identified by using clinical instruments designed to quantify severity of illness, patient stability, or weaning readiness. The instruments used were the Acute Physiology and Chronic Health Evaluation (APACHE III), the Therapeutic Intervention Scoring System (TISS), the Burns Wean Assessment Program (BWAP), and the Wean Index (WI). The stages were adapted from those proposed by the American Association of Critical Care Nurses Third National Study Group's Weaning Continuum Model. DESIGN: Prospective, convenience cohort. This study was part of a larger study designed to test an outcomes managed approach to weaning by using an outcomes manager and a clinical pathway. SETTING: University medical intensive care unit. PATIENTS: Adult patients requiring mechanical ventilation >3 days admitted to the medical intensive care unit between November 1994 and May 1995. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Scores for the APACHE III, TISS, BWAP, and WI were collected on 97 patients every other day until they weaned, were transferred, or died. Outcomes described for each stage of weaning were dated on the clinical pathway when achieved. Comments about patient stability and ventilator progress also were recorded along with a subjective determination of the stage of weaning. We used decision rules to identify time intervals for each stage of weaning and outcomes attained by stage. Finally, APACHE III, TISS, BWAP, and WI scores were placed in each stage by date for analysis. The APACHE III, TISS, and BWAP scores were able to differentiate the acute, prewean, and wean stages but not the outcome stage. CONCLUSIONS: By identifying distinct scores for each stage, we may be able to better explore appropriate interventions for the stages as well as predict weaning outcomes. Indices that include physiologic and respiratory factors can differentiate weaning stages, but respiratory factors alone cannot.


Assuntos
APACHE , Cuidados Críticos , Técnicas de Apoio para a Decisão , Desmame do Respirador/métodos , Análise de Variância , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Prognóstico , Estudos Prospectivos , Índice de Gravidade de Doença
9.
J Gen Virol ; 81(Pt 7): 1825-32, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10859389

RESUMO

The human papillomavirus type 16 (HPV-16) status of 43 cervical biopsies, which had been characterized histologically as normal, various grades of cervical intraepithelial neoplasia (CIN) and invasive squamous cell carcinoma, was examined by using (i) a novel antibody against the HPV-16 E2 protein, (ii) sensitive HPV-16 DNA in situ hybridization and (iii) microdissection/PCR for the E2 ORF. The data indicate that E2 protein expression is highest in koilocytes in lower-grade CIN (I), but decreases with increasing grade, whereas the detection of HPV DNA is delayed until CIN I/II, rising to the highest levels in carcinoma cells. Co-localization of E2 with HPV-16 DNA-positive cells was most commonly observed in koilocytes in CIN II lesions. PCR analyses of microdissected epithelium from the same or serial sections indicated that E2 ORFs were retained in an intact form in a number of higher-grade CIN lesions and invasive carcinomas.


Assuntos
Carcinoma de Células Escamosas/virologia , DNA Viral/análise , Proteínas de Ligação a DNA , Proteínas Oncogênicas Virais/análise , Papillomaviridae/genética , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Feminino , Humanos , Hibridização In Situ , Proteínas Oncogênicas Virais/genética , Fases de Leitura Aberta , Papillomaviridae/isolamento & purificação , Reação em Cadeia da Polimerase
10.
Nature ; 403(6771): 805-9, 2000 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-10693813

RESUMO

Papillomaviruses cause warts and proliferative lesions in skin and other epithelia. In a minority of papillomavirus types ('high risk, including human papillomaviruses 16, 18, 31, 33, 45 and 56), further transformation of the wart lesions can produce tumours. The papillomavirus E2 protein controls primary transcription and replication of the viral genome. Both activities are governed by a approximately 200 amino-acid amino-terminal module (E2NT) which is connected to a DNA-binding carboxy-terminal module by a flexible linker. Here we describe the crystal structure of the complete E2NT module from human papillomavirus 16. The E2NT module forms a dimer both in the crystal and in solution. Amino acids that are necessary for transactivation are located at the dimer interface, indicating that the dimer structure may be important in the interactions of E2NT with viral and cellular transcription factors. We propose that dimer formation may contribute to the stabilization of DNA loops which may serve to relocate distal DNA-binding transcription factors to the site of human papillomavirus transcription initiation.


Assuntos
Proteínas de Ligação a DNA , Proteínas Oncogênicas Virais/química , Cristalografia por Raios X , DNA Viral/química , Dimerização , Genoma Viral , Humanos , Proteínas Oncogênicas Virais/isolamento & purificação , Papillomaviridae/química , Papillomaviridae/fisiologia , Conformação Proteica , Replicação Viral
11.
Heart ; 82(4): 531-3, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10490577

RESUMO

Neonates with pulmonary atresia and intact interventricular septum (PAIVS) do not have pulmonary vascular disease secondary to their heart abnormality. Persistent pulmonary hypertension of the newborn has not been described in association with this condition. The case is reported of a female neonate born with PAIVS, who preoperatively had no clinical evidence or any risk factors for persistent pulmonary hypertension of the newborn, but whose postoperative course was highly suggestive of persistent pulmonary hypertension; necropsy confirmed the features of pulmonary vascular disease.


Assuntos
Hipertensão Pulmonar/complicações , Atresia Pulmonar/complicações , Evolução Fatal , Feminino , Septos Cardíacos/anatomia & histologia , Humanos , Hipertensão Pulmonar/patologia , Hipertensão Pulmonar/cirurgia , Recém-Nascido , Pulmão/patologia , Artéria Pulmonar/patologia , Atresia Pulmonar/patologia , Atresia Pulmonar/cirurgia , Valva Tricúspide/patologia
12.
Br J Radiol ; 72(853): 48-54, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10341689

RESUMO

Before automatic exposure control was fitted to diagnostic X-ray sets, radiographers were faced with the problem of choosing the parameters that would give the best radiographic image. For a new X-ray set whose performance was unknown, this was no easy matter, and often required considerable trial and error because of the number of variables involved. To reduce the amount of work, special slide rules were invented which calculated the effect of some of these variables. Five such slide rules, dating from between about 1910 and 1950, are illustrated and discussed, including the light they shed on changes in radiographic practice over the years.


Assuntos
Radiografia/história , História do Século XX , Humanos , Doses de Radiação , Radiografia/instrumentação , Radiometria/história , Radiometria/instrumentação
13.
J Urol ; 161(4): 1301-3, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10081898

RESUMO

PURPOSE: Despite the controversy regarding the need for routine neonatal circumcision, most boys in the United States are circumcised. Physicians are commonly asked to perform circumcision after the neonatal period and are often unaware of the cost factors related to the timing and location of postneonatal circumcision. MATERIALS AND METHODS: We describe the medical and financial advantages of postneonatal circumcision with local versus general anesthesia. RESULTS: During a 30-month period 245 boys 6 months to 15 years old underwent circumcision under general anesthesia in the operating room. Hospital charges (facility and equipment) averaged $1,555 and anesthesia charges averaged $250. Therefore, the average cost for circumcision in the operating room was $1,805. During the same time period 287 infants 3 days to 9 months old (20% older than 3 months) underwent circumcision under local anesthesia in an office setting. The facility and equipment charge for these office procedures averaged $196. Overall, approximately $461,783 were saved in this 30-month period ($184,713 annually) by performing circumcision with local anesthesia in an office setting rather then in the operating room with general anesthesia. There was no significant difference in complication rates between the local and general anesthesia groups (1.4 versus 1.6%). CONCLUSIONS: Circumcision with local anesthesia can be performed easily and safely during the first several months of life and has many advantages. Parents prefer this method because it is more convenient and eliminates the risk of general anesthesia. The enormous cost savings using local as opposed to general anesthesia should prompt a reexamination of the location and timing of postneonatal circumcision.


Assuntos
Anestesia Local , Circuncisão Masculina/economia , Adolescente , Criança , Pré-Escolar , Análise Custo-Benefício , Humanos , Lactente , Masculino , Visita a Consultório Médico
14.
Nephrol Dial Transplant ; 13(3): 704-10, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9550650

RESUMO

BACKGROUND: Allograft survival among black recipients is poorer than among whites. Delayed allograft function is associated with a significant reduction in renal allograft survival. The relationship between delayed allograft function and black race is incompletely specified and was the focus of this investigation. METHODS: A non-concurrent study of 325 recipients of cadaveric allografts followed for the occurrence of delayed allograft function defined as dialysis during the first week following transplantation for the principal analysis. A secondary definition of delayed allograft function was formulated based on the serum creatinine 2 weeks after transplantation. Unadjusted and adjusted logistic regression analysis were used to examine the unconfounded relationship between race and delayed allograft function. RESULTS: Fifty-seven of 91 (62.6%) black recipients experienced delayed allograft function compared to 113 of 234 (48.3%) whites. The odds ratio for black race as a predictor of delayed allograft function was 1.80, P=0.02, (95% CI, 1.09, 2.95). This finding was stable despite adjustment for other predictors of delayed allograft function in a multivariate model, but the precision of this estimate was less (P=0.10) because of missing data. Additionally, adjusted models with imputed values for missing covariates, models using a secondary definition of delayed allograft function, and models excluding patients whose cyclosporin therapy was delayed, all consistently demonstrated a similar association between black race and delayed allograft function. CONCLUSIONS: This study demonstrated an increased risk of delayed allograft function among black recipients. This relationship may play a role in the poorer allograft outcomes experienced by black recipients. Given the negative effect of delayed allograft function on allograft survival, efforts to identify its modifiable risk factors should be a high priority.


Assuntos
População Negra , Sobrevivência de Enxerto , Transplante de Rim , População Branca , Adulto , Fatores Etários , Nefropatias Diabéticas/complicações , Feminino , Teste de Histocompatibilidade , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fatores de Tempo , Preservação de Tecido
15.
Heart Lung ; 27(1): 58-62, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9493884

RESUMO

OBJECTIVE: To determine the incidence of obstruction and colonization in adult patients in the surgical and medical intensive care units who received inner cannula changes daily versus those who did not. DESIGN: Quasi-experimental prospective study using a convenience sample of patients randomly assigned to one of two methods. SETTING: Mid-Atlantic university-affiliated tertiary care center. PATIENTS: Sixty patients within 24 hours of receiving a surgical tracheostomy. OUTCOME MEASURES: Obstruction and bacterial colonization of inner cannula. INTERVENTIONS: All inner cannulas were checked daily for obstruction and cultured on postoperative days 1 and 3. RESULTS: No statistically significant difference was noted in colonization (p = 0.13) between protocols, and no obstructions were noted in either. CONCLUSION: The study suggests that the routine practice in critical care units of changing tracheostomy inner cannulas may be unnecessary. Although the results of this study are limited, and may not be generalized to other populations, it demonstrates that practice standards related to the care of tracheostomy inner cannula need to be challenged.


Assuntos
Intubação Intratraqueal/enfermagem , Traqueostomia/enfermagem , Adulto , Infecções Bacterianas/epidemiologia , Custos e Análise de Custo , Equipamentos Descartáveis , Feminino , Humanos , Intubação Intratraqueal/instrumentação , Masculino , Projetos Piloto , Estudos Prospectivos , Respiração Artificial , Fatores de Tempo , Traqueostomia/instrumentação
16.
Am J Crit Care ; 7(1): 45-57; quiz 58-9, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9429683

RESUMO

BACKGROUND: Outcomes management that uses critical pathways may decrease costs while improving outcomes for patients who require prolonged mechanical ventilation. OBJECTIVE: To study the efficacy of an outcomes-managed approach to weaning patients from prolonged (more than 3 days) mechanical ventilation. METHODS: A method of multidisciplinary care delivery was designed that included an outcomes manager, a care pathway for patients receiving mechanical ventilation, and weaning protocols. Data collection consisted of three parts: a retrospective review of 124 patients who required prolonged ventilation during a 1-year period before implementation of the care model, a 6-month prospective study in which 91 patients were alternately assigned by month to an outcomes-managed approach or a non-outcomes-managed approach, and a 6-month prospective study of 90 patients in which an outcomes-managed approach without alternate-month assignment was used. RESULTS: Outcomes management had no significant effect on total duration of mechanical ventilation or length of stay in the hospital, days of mechanical ventilation without tracheostomy, days of mechanical ventilation with tracheostomy, or outcome (weaned, withdrawal from mechanical ventilation, death, or transfer without weaning). However, duration of mechanical ventilation was 1.3 days shorter, length of stay in the hospital was 2.1 days shorter, and the cost per case was $ 3341 less for patients in the outcomes-managed group than for patients in the non-outcomes-managed group. CONCLUSION: Outcomes-managed care did not have a significant effect on duration of ventilation, length of stay in the hospital, or outcome in patients receiving long-term mechanical ventilation.


Assuntos
Procedimentos Clínicos , Avaliação de Processos e Resultados em Cuidados de Saúde , Desmame do Respirador/métodos , Adulto , Idoso , Cuidados Críticos , Estudos de Avaliação como Assunto , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Administração dos Cuidados ao Paciente/métodos , Planejamento de Assistência ao Paciente , Estudos Prospectivos , Projetos de Pesquisa , Estudos Retrospectivos , Fatores de Tempo , Traqueostomia
17.
Acta Crystallogr D Biol Crystallogr ; 54(Pt 6 Pt 2): 1471-4, 1998 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-10089541

RESUMO

The N-terminal transactivation domain of the E2 protein from human papillomavirus type 16 has been crystallized by vapour diffusion. Crystals belong to the space group P3121 (or P3221) with unit-cell dimensions a = b = 54.3, c = 155.5 A. There is one molecule per asymmetric unit with a solvent content of 55%. Crystals diffract to at least 2.5 A resolution and complete X-ray data to 3.4 A have been collected on a conventional laboratory source. This 201 amino-acid domain of the E2 protein has been shown to interact functionally with both the HPV E1 protein and at least three cellular transcription factors, to fulfil its role in the control of viral transcription and replication. A knowledge of the structural basis of these multiple interactions should lead to a fuller understanding of the mechanism of action of this key regulator of the HPV life cycle.


Assuntos
Proteínas de Ligação a DNA , Proteínas Oncogênicas Virais/química , Papillomaviridae/química , Clonagem Molecular , Cristalização , Cristalografia por Raios X , Escherichia coli , Congelamento , Humanos , Proteínas Oncogênicas Virais/biossíntese , Proteínas Oncogênicas Virais/genética , Proteínas Oncogênicas Virais/isolamento & purificação , Papillomaviridae/genética , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/isolamento & purificação
18.
J Pathol ; 186(3): 275-80, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10211116

RESUMO

Specific antibodies against the C-terminus of E2, produced by affinity purification of polyclonal antisera, have been used to identify the cellular populations which express the HPV 16 E2 transcription factor, in a series of formalin-fixed, paraffin-embedded cervical tissues. Cases were selected for both the presence of HPV 16 DNA (confirmed by multiple gene-specific PCR detections) and the presence of multiple grades of cervical intraepithelial neoplasia (CIN). The data indicate that E2 expression is highest in CIN I and in koilocytic lesions. Lower expression was observed in CIN II and little in CIN III lesions. In contrast, there was some restoration of E2 expression in invasive carcinomas, although the intracellular distribution was much more diffuse. The location of E2 expression to the superficial layers of the cervical epithelium, as well as the occurrence of some basal expression in CIN I, suggests that antibodies against HPV 16 E2 could be a useful adjunct to standard histological techniques for the detection of 'at-risk' patients as part of a cervical screening programme.


Assuntos
Proteínas de Ligação a DNA , Proteínas Oncogênicas Virais/análise , Papillomaviridae , Displasia do Colo do Útero/patologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/virologia , Feminino , Humanos , Imuno-Histoquímica , Reação em Cadeia da Polimerase
19.
Protein Eng ; 10(4): 423-33, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9194168

RESUMO

Single-chain variable fragments (scFvs) of anti-neuraminidase antibody NC10 were constructed by joining the VH and VL domains with 10-residue (Gly4Ser)2 and five-residue (Gly4Ser) linkers; a zero-residue linker scFv was constructed by joining the C-terminal residue of the VH domain to the N-terminus of the VL domain. The scFv with the 10- and five-residue linkers exclusively formed dimeric antibody fragments (M(r) 52000). These were shown to be bivalent and were able to cross-link two neuraminidase tetramers to form a 'sandwich' type complex; each antigen combining site could also bind an anti-idiotype Fab'. The zero-residue linker scFv (M(r) 70000) was shown to form a trimer with three active antigen combining sites, each binding an anti-idiotype Fab' to yield a complex of M(r) 212000. The orientation of the combining sites in the zero-residue linker scFv, however, was such that it could not cross-link tetramers of neuraminidase. BIAcore biosensor experiments showed that the affinity of each individual antigen combining site in both the 10- and five-residue linker scFv dimers and zero-residue linker scFv trimer was essentially the same when the scFvs were immobilized onto the sensor surface. However, when the scFvs were used as the analyte, the dimeric and trimeric scFvs showed an apparent increase in binding affinity due to the avidity of binding the multivalent scFvs.


Assuntos
Fragmentos de Imunoglobulinas/química , Região Variável de Imunoglobulina/química , Neuraminidase/imunologia , Sequência de Aminoácidos , Sequência de Bases , Técnicas Biossensoriais , Cromatografia de Afinidade , Cromatografia Líquida de Alta Pressão , DNA , Dimerização , Fragmentos Fab das Imunoglobulinas/imunologia , Fragmentos Fab das Imunoglobulinas/metabolismo , Idiótipos de Imunoglobulinas/metabolismo , Modelos Moleculares , Dados de Sequência Molecular , Peso Molecular , Estrutura Terciária de Proteína
20.
Nephrol Dial Transplant ; 11(7): 1306-13, 1996 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-8672027

RESUMO

BACKGROUND: Mechanisms by which delayed allograft function reduces renal allograft survival are poorly understood. This study evaluated the relationship of delayed allograft function to acute rejection and long-term survival of cadaveric allografts. METHODS: 338 recipients of cadaveric allografts were followed until death, resumption of dialysis, retransplantation, loss to follow-up, or the study's end, which ever came first. Delayed allograft function was defined by dialysis during the first week following transplantation. Multivariate Cox proportional hazards survival analysis was used to assess the relationship of delayed allograft function to rejection and allograft survival. RESULTS: Delayed allograft function, recipient age, preformed reactive antibody levels, prior kidney transplantation, recipient race, rejection during the first 30 days and rejection subsequent to 30 days following transplantation were predictive of allograft survival in multivariate survival models. Delayed allograft function was associated with shorter allograft survival after adjustment for acute rejection and other covariates (relative rate of failure [RR]+1.72 [95% CI, 1.07, 2.76]). The adjusted RR of allograft failure associated with any rejection during the first 30 days was 1.99 (1.23, 3.21), and for rejection subsequent to the first 30 days was 3.53 (2.9 08, 6.00). The impact of delayed allograft function did not change substantially (RR=1.84 [1.15, 2.95]) in models not controlling for acute rejection. These results were stable among several subgroups of patients and using alternative definitions of allograft survival and delayed allograft function. CONCLUSIONS: This study demonstrates that delayed allograft function and acute allograft rejection have important independent and deleterious effects on cadaveric allograft survival. These results suggest that the effect of delayed allograft function is mediated, in part, through mechanisms not involving acute clinical rejection.


Assuntos
Transplante de Rim/fisiologia , Doença Aguda , Adulto , Estudos de Coortes , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Transplante de Rim/efeitos adversos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Fatores de Tempo
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