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1.
BMC Public Health ; 22(1): 1470, 2022 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-35915479

RESUMO

BACKGROUND: Regular testing for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is an important strategy for controlling virus outbreaks on university campuses during the COVID-19 pandemic but testing participation rates can be low. The Residence-Based Testing Participation Pilot (RB-TPP) was a novel intervention implemented at two student residences on a large UK university campus over 4 weeks. The aim of the pilot was to increase the frequency of asymptomatic SARS-CoV-2 saliva testing onsite. This process evaluation aimed to determine whether RB-TPP was implemented as planned and identify implementation barriers and facilitators. METHODS: A mixed-methods process evaluation was conducted alongside the RB-TPP. Evaluation participants were students (opting in, or out of RB-TPP) and staff with a role in service provision or student support. Monitoring data were collected from the intervention delivery team and meeting records. Data were collected from students via online survey (n = 152) and seven focus groups (n = 30), and from staff via individual interviews (n = 13). Quantitative data were analysed descriptively and qualitative data thematically. Barriers and facilitators to implementation were mapped to the 'Capability, Opportunity, Motivation-Behaviour' (COM-B) behaviour change framework. RESULTS: Four hundred sixty-four students opted to participate in RB-TPP (98% of students living onsite). RB-TPP was implemented broadly as planned but relaxed social distancing was terminated early due to concerns relating to national escalation of the COVID-19 Delta variant, albeit testing continued. Most students (97.9%) perceived the period of relaxed social distancing within residences positively. The majority engaged in asymptomatic testing (88%); 46% (52% of testers) were fully compliant with pre-determined testing frequency. Implementation was facilitated by convenience and efficiency of testing, and reduction in the negative impacts of isolation through opportunities for students to socialise. Main barriers to implementation were perceived mixed-messages about the rules, ambivalent attitudes, and lack of adherence to COVID-19 protective measures in the minority. CONCLUSIONS: This process evaluation identifies factors that help or hinder the success of university residence-based outbreak prevention and management strategies. RB-TPP led to increased rates of SARS-CoV-2 testing participation among students in university residences. Perceived normalisation of university life significantly enhanced student mental wellbeing. The complexity and challenge generated by multiple lines of communication and rapid adaptions to a changing pandemic context was evident. TRIAL REGISTRATION NUMBER: UKAS 307727-02-01; Pre-results. CLINICALTRIALS: gov Identifier: NCT05045989 ; post-results (first posted, 16/09/21). ETHICAL APPROVAL: Faculty of Medicine & Health Sciences Research Ethics Committee, University of Nottingham (Ref: FMHS 96-0920).


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/epidemiologia , COVID-19/prevenção & controle , Teste para COVID-19 , Humanos , Pandemias/prevenção & controle , Reino Unido/epidemiologia , Universidades
2.
Public Health ; 201: 98-107, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34801843

RESUMO

OBJECTIVES: Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) was identified in late 2019, spreading to over 200 countries and resulting in almost two million deaths worldwide. The emergence of safe and effective vaccines provides a route out of the pandemic, with vaccination uptake of 75-90% needed to achieve population protection. Vaccine hesitancy is problematic for vaccine rollout; global reports suggest only 73% of the population may agree to being vaccinated. As a result, there is an urgent need to develop equitable and accessible interventions to address vaccine hesitancy at the population level. STUDY DESIGN: & Method: We report the development of a scalable digital intervention seeking to address COVID-19 vaccine hesitancy and enhance uptake of COVID-19 vaccines in the United Kingdom. Guided by motivational interviewing (MI) principles, the intervention includes a series of therapeutic dialogues addressing 10 key concerns of vaccine-hesitant individuals. Development of the intervention occurred linearly across four stages. During stage 1, we identified common reasons for COVID-19 vaccine hesitancy through analysis of existing survey data, a rapid systematic literature review, and public engagement workshops. Stage 2 comprised qualitative interviews with medical, immunological, and public health experts. Rapid content and thematic analysis of the data provided evidence-based responses to common vaccine concerns. Stage 3 involved the development of therapeutic dialogues through workshops with psychological and digital behaviour change experts. Dialogues were developed to address concerns using MI principles, including embracing resistance and supporting self-efficacy. Finally, stage 4 involved digitisation of the dialogues and pilot testing with members of the public. DISCUSSION: The digital intervention provides an evidence-based approach to addressing vaccine hesitancy through MI principles. The dialogues are user-selected, allowing exploration of relevant issues associated with hesitancy in a non-judgmental context. The text-based content and digital format allow for rapid modification to changing information and scalability for wider dissemination.


Assuntos
COVID-19 , Vacinas , Vacinas contra COVID-19 , Humanos , SARS-CoV-2 , Vacinação , Hesitação Vacinal
3.
HIV Med ; 14(2): 108-14, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23171088

RESUMO

OBJECTIVES: The aim of the study was to qualitatively and semiquantitatively characterize the expression of the principal HIV co-receptors chemokine (C-C motif) receptor 5 (CCR5) and chemokine (C-X-C motif) receptor 4 (CXCR4) on susceptible CD4 T-helper cell, monocyte/macrophage and Langerhans dendritic cell populations within the cervical epithelia of asymptomatic women attending a genitourinary medicine clinic. METHODS: Of 77 asymptomatic women recruited, 35 were excluded: 21 because they were found to have bacterial vaginosis, eight because they were found to have candida and six for other reasons. Cervical cytobrush samples from 11 women with Chlamydia trachomatis infection and 31 women without any detectable genital infection were stained with fluorescently labelled antibodies specific for cell surface CCR5, CXCR4, CD4, CD3, CD1a and CD19 expression, then analysed by flow cytometry. RESULTS: CD4/CD3 T-helper cells (84%), CD1a Langerhans dendritic cells (75%) and CD4/CD14 monocytes/macrophages (59%) were detected in the samples. CCR5 and CXCR4 HIV co-receptor expression was observed on 46-86% of the above subsets. CD1a cells exhibited significantly higher CCR5 and CXCR4 positivity and median fluorescence than CD4 cells and higher CXCR4 positivity and median fluorescence than CD14 cells (P < 0.05 or less). Increased detection of CCR5 over CXCR4 was seen in CD14 cells (P < 0.05). No significant differences in CCR5 or CXCR4 expression were found in samples from asymptomatic women with or without chlamydial infection. CONCLUSIONS: Co-receptor expression confirms the potential for CD1a Langerhans cells, monocytes/macrophages and T-helper cells in the cervix as primary targets for HIV infection. Previously observed selective transmission of CCR5-tropic isolates cannot be accounted for by a lack of CXCR4-expressing CD4 cervical immune cells. We were unable to identify any specific impact of chlamydial infection on co-receptor expression in this study.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Colo do Útero/imunologia , Células Dendríticas/imunologia , Soropositividade para HIV/imunologia , HIV-1/imunologia , Macrófagos/imunologia , Receptores CCR5/imunologia , Receptores CXCR4/imunologia , Adulto , Diferenciação Celular , Colo do Útero/patologia , Colo do Útero/virologia , Chlamydia trachomatis/isolamento & purificação , Feminino , Citometria de Fluxo , Soropositividade para HIV/patologia , HIV-1/fisiologia , Humanos , Subpopulações de Linfócitos T , Vaginose Bacteriana/diagnóstico , Vaginose Bacteriana/microbiologia , Tropismo Viral , Replicação Viral , Saúde da Mulher
4.
Curr Top Microbiol Immunol ; 317: 1-38, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17990788

RESUMO

Liver failure associated with hepatitis C virus (HCV) accounts for a substantial portion of liver transplantation. Although current therapy helps some patients with chronic HCV infection, adverse side effects and a high relapse rate are major problems. These problems are compounded in liver transplant recipients as reinfection occurs shortly after transplantation. One approach to control reinfection is the combined use of specific antivirals together with HCV-specific antibodies. Indeed, a number of human and mouse monoclonal antibodies to conformational and linear epitopes on HCV envelope proteins are potential candidates, since they have high virus neutralization potency and are directed to epitopes conserved across diverse HCV genotypes. However, a greater understanding of the factors contributing to virus escape and the role of lipoproteins in masking virion surface domains involved in virus entry will be required to help define those protective determinants most likely to give broad protection. An approach to immune escape is potentially caused by viral infection of immune cells leading to the induction hypermutation of the immunoglobulin gene in B cells. These effects may contribute to HCV persistence and B cell lymphoproliferative diseases.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Anticorpos Anti-Hepatite C/uso terapêutico , Hepatite C/terapia , Sequência de Aminoácidos , Linfócitos B/imunologia , Linfócitos B/virologia , Epitopos , Genes env , Hepacivirus/genética , Hepacivirus/imunologia , Anticorpos Anti-Hepatite C/biossíntese , Humanos , Dados de Sequência Molecular , Testes de Neutralização , Hipermutação Somática de Imunoglobulina , Proteínas do Envelope Viral/imunologia
5.
Science ; 152(3722): 650-1, 1966 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-17779506

RESUMO

The injection of 60 micrograms of 9,10-dimethyl-1,2-benzanthracene into newborn mice gave rise to a very high incidence of malignant thymomas. The tumor incidence was directly related to the dose of the carcinogen. The neonatal injection of the carcinogen also resulted in a depression in the immune response when the animals were challenged with an antigert as early as 4 weeks or as late as 11 weeks after administration of the carcinogen.

6.
J Viral Hepat ; 15(5): 339-45, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18221305

RESUMO

Hepatitis C virus (HCV) causes acute and chronic liver diseases in humans. Its two envelope glycoproteins, E1 and E2, provide a target for host immune recognition. HCV genotypes are classified into six genetic groups. To study the role of anti-HCV E1 and E2 (anti-E1E2) in HCV disease, the correlation between antibody level and viral load, genotype, disease severity and response to treatment was investigated. The levels of antibodies to HCV glycoproteins E1 and E2 antibodies were evaluated in 230 sera of patients with chronic hepatitis C by enzyme-linked immunosorbent assay. The antigens used were recombinant HCV glycoproteins derived from genotype 1 (H77c) and genotype 3 (UKN3A1.28). Seroreactivity was greater when sera were tested against antigen derived from their homologous genotype than against heterologous antigen. Reactivity against UKN3A1.28 in sera from patients infected with genotype 3 was significantly higher than corresponding reactivity between patients infected with genotype 1 and H77c. The seroreactivity was inversely proportional to the viral load and to the degree of liver fibrosis. The pre-treatment level of anti-E1E2 was higher in sustained responders to combination therapy. These results demonstrate that seroreactivity against E1E2 depends upon the genotypic origin of the E1E2 antigens and the infecting genotype, and suggest a possible protective effect of anti-E1E2 against disease progression.


Assuntos
Anticorpos Antivirais/sangue , Hepacivirus/imunologia , Hepatite C Crônica/imunologia , Hepatite C Crônica/patologia , Proteínas do Envelope Viral/imunologia , Antivirais/uso terapêutico , Ensaio de Imunoadsorção Enzimática , Genótipo , Hepacivirus/classificação , Hepacivirus/genética , Hepatite C Crônica/tratamento farmacológico , Humanos , Cirrose Hepática/patologia , Índice de Gravidade de Doença , Estatística como Assunto , Resultado do Tratamento , Carga Viral
7.
J Natl Cancer Inst ; 62(3): 605-10, 1979 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-216842

RESUMO

Chromosome banding techniques were used to examine the karyotype of tumor cells from thymic lymphomas induced by three different carcinogens (X-irradiation, polycyclic aromatic hydrocarbons, and an endogenous leukemogenic virus) after injection into neonatal mice of 2 different inbred mouse strains (CFW/D and C57BL/Ka). A total of 89 tumors were studied, and of these 85.4% were characterized by a modal chromosome number of 41. The additional chromosome was the result of a specific abnormality identified as trisomy of chromosome no. 15. The results obtained were independent of the carcinogenic agents and the strain of mouse used. Of the 13 tumors found to have a normal chromosome complement, 4 were induced by X-irradiation and the remaining 9 by the chemical carcinogens. All 15 virus-induced tumors analyzed had a modal chromosome number of 41.


Assuntos
Linfoma/genética , Neoplasias Induzidas por Radiação/genética , Compostos Policíclicos , Neoplasias do Timo/genética , Trissomia , Animais , Vírus da Leucemia Murina , Linfoma/etiologia , Camundongos , Camundongos Endogâmicos , Neoplasias Experimentais/genética , Neoplasias do Timo/etiologia , Infecções Tumorais por Vírus/genética
8.
J Natl Cancer Inst ; 59(1): 179-83, 1977 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-875053

RESUMO

A temperature-sensitive mutant of Moloney murine leukemia virus defective in an early function and injected into newborn mice produced lower limb paralysis. Susceptible mice were inbred strains CFW/D, CBA/H, C3H/Bi/Ka, and outbred NIH Swiss stock. Inbred W/Fu rats and C57BL/Ka mice did not develop the paralysis, though the latter were infected with virus; the sera from these mice produced paralysis in susceptible CFW mice.


Assuntos
Vírus da Leucemia Murina de Moloney/patogenicidade , Paralisia/etiologia , Infecções Tumorais por Vírus/patologia , Animais , Animais Recém-Nascidos , Vírus Defeituosos/isolamento & purificação , Extremidades , Camundongos , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Camundongos Endogâmicos , Vírus da Leucemia Murina de Moloney/isolamento & purificação , Mutação , Paralisia/microbiologia , Paralisia/patologia , Ratos , Ratos Endogâmicos WF , Medula Espinal/ultraestrutura , Temperatura
9.
FEBS Lett ; 456(3): 399-402, 1999 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-10462052

RESUMO

The histidine-rich Ca2+ binding protein (HRC) resides in the sarcoplasmic reticulum of muscle and binds Ca2+. Since Ca2+ concentrations can regulate gene expression via calcineurin, the mouse homologue of HRC (mHRC) was isolated and characterized. mHRC was detected in muscle progenitor cells, in primary clonal thymic tumors and a tumor cell line, suggesting a broader role for mHRC than in Ca2+ storage during muscle contraction. mHRC was present in the perinuclear region of myoblasts. To examine if it can regulate gene expression, mHRC was overexpressed in cells differentiating into cardiac and skeletal muscle. mHRC had no effect on cardiogenesis or myogenesis. Therefore, if mHRC plays a role in the regulation of gene expression during cellular differentiation, it does not appear to be either rate-limiting or inhibitory.


Assuntos
Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , Diferenciação Celular/fisiologia , Linhagem Celular , Clonagem Molecular , Regulação da Expressão Gênica , Humanos , Camundongos , Dados de Sequência Molecular , Desenvolvimento Muscular , Músculo Esquelético/crescimento & desenvolvimento , Músculo Esquelético/metabolismo , Sequências Repetitivas de Aminoácidos , Homologia de Sequência de Aminoácidos , Frações Subcelulares , Neoplasias do Timo/metabolismo , Células Tumorais Cultivadas
10.
J Acquir Immune Defic Syndr (1988) ; 5(10): 978-87, 1992 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1453327

RESUMO

In this project, we examined the spectrum of AIDS-related conditions and variations in associated inpatient mortality for AIDS patients treated in a national sample of hospitals. We identified 10,538 adult discharges with a diagnosis indicating AIDS from 258 hospitals from a national sample of 438 acute-care hospitals with 6 million discharges in 1986-1987. Opportunistic and other infections occurred in 55.9 and 37.9%, respectively, of AIDS discharges, and inpatient fatality rates varied considerably depending on complication type(s) and comorbidities. Clinical conditions were more important predictors of inpatient death than demographic or treatment site characteristics. Among opportunistic infections, odds of inpatient death were significantly increased for progressive multifocal leukoencephalopathy (odds ratio [OR] = 2.8), Pneumocystis carinii pneumonia (OR = 2.4), cryptococcosis (OR = 1.6), atypical mycobacterial infections (OR = 1.6), and toxoplasmosis (OR = 1.3). Odds of inpatient death were also significantly increased by non-AIDS-defining infections causing septicemia (OR = 3.1) or CNS involvement (OR = 1.6) or pulmonary involvement (OR = 1.5). After controlling for clinical conditions, significant differences in odds of death persisted across regions, age, and ethnic groups. Increases in hospitals' AIDS treatment experience were associated with a significant decrease in odds of inpatient death. These analyses provide a national perspective on the diversity of AIDS-related clinical conditions and their relative effects on inpatient mortality.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/mortalidade , Síndrome da Imunodeficiência Adquirida/mortalidade , Mortalidade Hospitalar , Síndrome da Imunodeficiência Adquirida/classificação , Síndrome da Imunodeficiência Adquirida/complicações , Demografia , Soropositividade para HIV , Humanos , Análise Multivariada , Razão de Chances , Alta do Paciente , Análise de Regressão , Estados Unidos
11.
Leuk Res ; 13(7): 553-9, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2548040

RESUMO

CFW/D mice injected neonatally with a type B retrovirus, (DMBA-LV), rapidly develop thymic lymphomas. The present study examined simultaneously the karyotype and the expression of surface antigens on thymocytes from DMBA-LV treated mice at 28, 35 and 42 days of age during the development of lymphomas, and of cells from primary lymphomas. DMBA-LV treatment resulted in disturbances in the proportions of thymic Lyt 1+2-, Lyt 1-2+ and Lyt 1+2+ subpopulations. As a group, virus-treated mice showed a significant decrease in the size of the Lyt 1+2- subpopulation in thymuses during tumor development. However, developing tumors and primary tumors showed individual patterns of alteration in the proportions of thymocyte subpopulations rather than consistent trends for any one thymocyte subpopulation to increase or decrease. Cells with the abnormal chromosome complement, trisomy 15, were present early in the development of tumors and became the predominant karyotype in fully developed tumors. A correlation between the appearance of trisomy 15 and a particular thymocyte surface antigen phenotype was not detected. The results suggest that retrovirus infection disrupts, but does not eliminate the ability of developing thymocytes to form phenotypically distinct subpopulations.


Assuntos
Biomarcadores Tumorais/análise , Vírus da Leucemia Murina/fisiologia , Linfoma/classificação , Neoplasias do Timo/classificação , 9,10-Dimetil-1,2-benzantraceno , Animais , Antígenos de Diferenciação de Linfócitos T/análise , Antígenos de Superfície/análise , Aberrações Cromossômicas/genética , Transtornos Cromossômicos , Cariotipagem , Linfoma/etiologia , Linfoma/genética , Camundongos , Camundongos Endogâmicos , Fenótipo , Linfócitos T/classificação , Neoplasias do Timo/etiologia , Neoplasias do Timo/genética
12.
Leuk Res ; 13(7): 561-71, 1989.
Artigo em Inglês | MEDLINE | ID: mdl-2548041

RESUMO

This study examined the surface antigen phenotype, karyotype and proviral integration patterns of cultured cells from murine thymic lymphomas induced by injecting neonatal mice with the type B leukemogenic retrovirus (DMBA-LV). Cells from the primary thymic lymphomas were established in mass culture and from these, clonal tumor cell lines were derived. During in vitro culture of lymphoma cells, Lyt 1-2+ cells predominated with an apparent selection against cells of the Lyt 1+2- and Lyt 1+2+ phenotypes. Of 21 cloned lines established, five had a diploid chromosome complement and expressed the Lyt 1-2+ phenotype. The other 16 clones lines were characterized by trisomy of chromosome 15 and expressed the Lyt 1+2+ or Lyt 1-2+ phenotype. Cells characterized by either a diploid or trisomy chromosome complement were capable of growth in vivo. Southern blot analyses showed that during growth in culture, cells from the mass cultures and cloned lines continued to acquire low numbers of new integrated DMBA-LV proviral copies while maintaining the basic proviral integration pattern present in the DNA from cells of the primary lymphomas. These findings support the notion that the acquisition of new genetic information in cells from DMBA-LV-induced thymic lymphomas may contribute to the continual generation of tumor heterogeneity.


Assuntos
Antígenos de Superfície/análise , Biomarcadores Tumorais/análise , Vírus da Leucemia Murina/genética , Linfoma/classificação , Provírus/genética , Neoplasias do Timo/classificação , 9,10-Dimetil-1,2-benzantraceno , Animais , Linhagem Celular , Células Clonais/classificação , Células Clonais/microbiologia , DNA Viral/isolamento & purificação , Cariotipagem , Linfoma/genética , Linfoma/microbiologia , Camundongos , Camundongos Endogâmicos , Fenótipo , Linfócitos T/classificação , Neoplasias do Timo/genética , Neoplasias do Timo/microbiologia , Células Tumorais Cultivadas/classificação , Células Tumorais Cultivadas/microbiologia
13.
Cancer Genet Cytogenet ; 14(3-4): 303-11, 1985 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-2981606

RESUMO

The present study examined the balance in the proportion of cells with either trisomy 15 or a diploid chromosome complement during short-term culture in vitro. Neonatal CFW/D mice were given an intrathymic injection of an endogenous virus (DMBA-LV) isolated from a DMBA-induced thymic lymphoma. The thymus was removed at the terminal leukemic stage, and the cells from each enlarged thymus were cultured in quintuplet. At 0, 6, 12, 24, and 48 hr, cultures were given colcemid for 2 hr prior to harvesting for chromosome examination. The analyzed lymphomas can be divided into three groups according to the characteristics of their stem lines and sidelines, as revealed by direct chromosome preparation (0 hr). Two groups consisted of lymphomas carrying a stem line with either trisomy 15 (group 1) or a diploid karyotype (group 2). A third group (group 3) consisted of lymphomas with a mixture of an abnormal stem line and sidelines. Chromosome analysis of cultures at subsequent times showed that there were fluctuations in the proportion of cells characterized as either stem line or sideline in all tumors at different times during culture. The initial sideline in group 1 tumors had a diploid complement. Although the proportion of the diploid cells increased in 5 of the 6 tumors following either 24 or 48 hr in culture, cells with a diploid karyotype remained as a sideline throughout the culture period. Similarly, the two tumors analyzed in group 2 showed that the initial sideline that contained trisomy 15 increased temporarily to become the stem line following 6 or 12 hr in culture. Group 3 tumors showed a slight variation in the proportion of cells with an abnormal stem line or sideline during culture. Considering all the data from the 10 tumors, 7 tumors had cells with a diploid karyotype, and, although the proportion of cells with this karyotype increased (4 tumors) or persisted (3 tumors) during 48 hr in culture, it remained as a sideline and was not overgrown by trisomy 15 stem line.


Assuntos
Aberrações Cromossômicas , Linfoma/genética , Neoplasias do Timo/genética , Animais , Células Cultivadas , Bandeamento Cromossômico , Cariotipagem , Vírus da Leucemia Murina , Leucemia Experimental/genética , Linfoma/etiologia , Camundongos , Ploidias , Neoplasias do Timo/etiologia , Fatores de Tempo , Trissomia
14.
J Virol Methods ; 44(1): 67-76, 1993 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8227279

RESUMO

An extremely sensitive and convenient microtiter plate solution hybridisation assay for the detection of HIV-1 PCR products was developed. The PCR product is labelled by direct incorporation of digoxigenin-dUTP and after denaturation is captured by a microtitre plate coated with a streptavidin-linked biotinylated probe. The PCR/probe hybrids are reacted with an alkaline phosphate conjugated anti-digoxigenin antibody and detected using an alkaline phosphatase enzyme amplification system. The use of uracil-N-glycosylase and dUTP instead of dTTP in the PCR is used to effectively control carry-over from previous PCR products. The assay can detect single HIV-1 DNA molecules in a background DNA of 0.75 microgram.


Assuntos
DNA Glicosilases , DNA Viral/análise , HIV-1/isolamento & purificação , N-Glicosil Hidrolases , Hibridização de Ácido Nucleico/métodos , Reação em Cadeia da Polimerase , Sequência de Bases , Primers do DNA , Sondas de DNA , DNA Antissenso , Nucleotídeos de Desoxiuracil , Digoxigenina , Genes env , Genes gag , HIV-1/genética , Microquímica/instrumentação , Dados de Sequência Molecular , Hibridização de Ácido Nucleico/instrumentação , Provírus/isolamento & purificação , Sensibilidade e Especificidade , Uracila-DNA Glicosidase
15.
J Virol Methods ; 37(2): 149-53, 1992 May.
Artigo em Inglês | MEDLINE | ID: mdl-1597505

RESUMO

Alkaline phosphatase amplification systems increase the sensitivity of enzyme-linked immunoassays (ELISAs). Here we describe a modified method by which levamisole is a component of the substrate buffer. This increases sensitivity by reducing the signal from non-specific alkaline phosphatases. The modified procedure was applied to an 'in house' HIV-1 p24 antigen capture assay and was shown to increase the sensitivity 4-fold as compared to the unmodified system. The performance of the modified amplification system is comparable to that of commercially available systems.


Assuntos
Fosfatase Alcalina , Ensaio de Imunoadsorção Enzimática , Proteína do Núcleo p24 do HIV/análise , Fosfatase Alcalina/normas , Ensaio de Imunoadsorção Enzimática/normas , Levamisol , Especificidade por Substrato
16.
J Virol Methods ; 88(1): 73-80, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10921844

RESUMO

Polymerase chain reaction (PCR) amplification of full-length envelope genes from the human immunodeficiency virus type 1 (HIV-1) directly from uncultured clinical samples is difficult. This paper describes a comparative assessment of the performance of three thermostable polymerases in an HIV-1 full-length envelope gene PCR. The PCR method utilising Expand HiFi polymerase was successful when using DNA samples extracted from a variety of sources including blood, semen and various tissues. This method generated high and specific yields of product from samples containing as little as one copy of HIV-1 proviral DNA. The resulting PCR products were suitable for a variety of downstream analytical methods including DNA sequence analysis.


Assuntos
DNA Polimerase Dirigida por DNA/metabolismo , Genes env/genética , HIV-1/genética , Reação em Cadeia da Polimerase/métodos , Provírus/genética , Sequência de Bases , DNA Viral/análise , Amplificação de Genes , Proteína gp160 do Envelope de HIV , Infecções por HIV/virologia , Humanos , Dados de Sequência Molecular , Sensibilidade e Especificidade , Análise de Sequência de DNA , Taq Polimerase/metabolismo
17.
J Virol Methods ; 94(1-2): 111-20, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11337045

RESUMO

The recent development of tagged RT-PCR and rTth RT-PCR has greatly improved strand-specific detection of hepatitis C virus (HCV) RNA but these assays are still prone to some false detection of the incorrect strand of RNA. In this study we aimed to address additional factors which contribute towards false detection of HCV RNA. Firstly the benefits of both tagged primers and the thermostable reverse transcriptase rTth during cDNA synthesis were combined and it was found that strand specificity was greatly improved without compromising sensitivity. The reliability of the assay was then optimised by addressing the following issues: control synthetic transcripts should be free of contaminating plasmid DNA, residual RT activity should be minimised in the presence of PCR primers and cDNA should be free of unincorporated tagged RT primer prior to PCR amplification. The alterations made to the assay eliminated completely false detection of the incorrect strand of RNA in the control assay whilst the correct strand was consistently detected at a cDNA dilution of 10(-3)-10(-4). Negative strand was not detected in RNA isolated from serum but was detected, at a ten-fold lower level than positive strand, in RNA isolated from liver tissue.


Assuntos
Hepacivirus/genética , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Replicação Viral , Enzimas Reparadoras do DNA , Exodesoxirribonucleases/metabolismo , Hepacivirus/isolamento & purificação , Hepatite C/virologia , Humanos , Fígado/patologia , Fígado/virologia , Plasmídeos , Sensibilidade e Especificidade
18.
Health Aff (Millwood) ; 16(5): 58-72, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9314676

RESUMO

The Health Insurance Portability and Accountability Act of 1996 (HIPAA) contains groundbreaking provisions to encourage the development of a national health information system through the establishment of standards. This paper compares statewide inpatient data systems to one standard--the Uniform Bill (UB)--to understand how standards have been used and how they can be improved. We recommend changes to the UB, note the need for better compliance, and suggest new standards for common, derived elements.


Assuntos
Coleta de Dados/normas , Bases de Dados Factuais/normas , Sistemas de Informação Hospitalar/normas , Redes de Comunicação de Computadores , Política de Saúde , Humanos , Seguro Saúde/legislação & jurisprudência , Governo Estadual , Estados Unidos
19.
Adv Exp Med Biol ; 114: 739-4, 1979.
Artigo em Inglês | MEDLINE | ID: mdl-88883

RESUMO

We have shown that permanently transformed T cells of a leukemic line (485-2) maintain their immunocompetent function and can be specifically activated by antigen. This cell line should facilitate investigations into the biochemical mechanisms of T cell activation and may help elucidate the nature of the T cell receptor.


Assuntos
Antígenos/imunologia , Leucemia Experimental/imunologia , Animais , Linhagem Celular , Epitopos , Eritrócitos/imunologia , Técnica de Placa Hemolítica , Cavalos , Camundongos , Ovinos
20.
J Natl Med Assoc ; 86(6): 449-58, 1994 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8078083

RESUMO

This article describes a retrospective study that compared the distribution of colorectal tumors among black and white discharges. A total of 188,109 discharges with colorectal cancer were selected from the Hospital Cost and Utilization Project, a national sample of hospitals with 34 million patient discharges from 1980 to 1987. Black/white differences were small for right, left, and rectal tumors; however, black discharges had a higher percentage of colorectal tumors with sites unspecified. From 1980 to 1987, 295 per 1000 discharges of blacks had an unspecified tumor location, compared with 229 per 1000 discharges of whites (a 29% difference). Black discharges had a higher proportion of unspecified tumors than whites regardless of cancer severity, discharge status, procedure type, age, sex, expected third-party payer, and year. Black/white differences were maintained across hospital characteristics (region, rural/urban location, teaching status, bed size, and ownership). Differences in specification of tumor site may be an indicator of poor continuity of care, poor access, or other quality-related measures.


Assuntos
População Negra , Neoplasias Colorretais/epidemiologia , População Branca , Idoso , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/patologia , Feminino , Hospitalização , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Classe Social , Estados Unidos/epidemiologia
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