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1.
BMC Health Serv Res ; 20(1): 513, 2020 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-32503525

RESUMO

BACKGROUND: Little is known about how to build leadership capacity to support implementation of evidence-based practices within health systems. We observed substantial variability across sites in uptake and sustainability of a peer-led educational outreach intervention for lay health workers (LHWs) providing tuberculosis care in Malawi. Feedback from peer-trainers (PTs) suggested that leadership may have contributed to the variation. We sought to assess the impact of PT leadership style on implementation, and to identify leadership traits of more successful PTs, to inform future implementation planning and to identify targets for leadership capacity building. METHODS: Qualitative study employing interviews with PTs and LHWs at high and low implementation sites, and review of study team and quarterly PT meeting notes. High implementation sites achieved high uptake, sustainability and fidelity of implementation including: close adherence to training content and process, high levels of coverage (training most or all eligible LHWs at their site), and outcomes were achieved with high levels of self reported competence with the intervention among both PTs and LHWs. Low implementation sites achieved limited coverage (<= 50% of LHWs trained), and intervention fidelity. RESULTS: Eight PTs and 10 LHWs from eight high and 10 low implementation sites participated in interviews. Leadership traits of more successful PTs included: flexibility in their approach to training, role modeling and provision of supportive supervision to support learning; addressing challenges proactively and as they occurred; collaborative planning; knowledgeable; and availability to support implementation. Traits unique to less successful PTs included: a poor attitude toward their role as PT and a passive-avoidant approach to challenges. CONCLUSION: This study identified leadership traits more common among unit level leaders at sites with higher uptake, sustainability, and fidelity of implementation. These findings provide a starting point for development and evaluation of a leadership capacity building intervention for unit level leaders to support implementation.


Assuntos
Agentes Comunitários de Saúde/educação , Educação Interprofissional/organização & administração , Liderança , Grupo Associado , Tuberculose/terapia , Adulto , Agentes Comunitários de Saúde/estatística & dados numéricos , Feminino , Humanos , Malaui , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Pesquisa Qualitativa , Melhoria de Qualidade
2.
Public Health ; 177: 19-25, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31494359

RESUMO

OBJECTIVES: Although evidence-based interventions (EBIs) and effective strategies to implement them exist, they cannot be used by policy makers and practitioners if they do not align with end users' needs. As such, adaptations to EBIs and implementation approaches are likely to occur to increase 'fit' with end users' capacity. This article describes an approach undertaken by a population health service delivery unit in one Australian state to develop an adapted implementation strategy to support the implementation of the mandatory healthy canteen policy (EBI) to all schools located in the service delivery region. STUDY DESIGN: This is a case study of adapting an intervention to improve implementation of the healthy canteen policy. METHODS AND RESULTS: This is a six-step pragmatic, empirically driven approach. The steps include (i) adapt, where appropriate, the EBI to facilitate implementation; (ii) identify end users' capacity for implementation; (iii) identify opportunities to adapt the implementation interventions while preserving meaningful intervention impact; (iv) undertake program adaptation; (v) develop training and resources to support delivery of implementation strategies and; (vi) evaluate the adapted intervention. This article describes the application of these steps by the authors to develop an adapted support strategy consistent with end users' needs. CONCLUSIONS: This study provides some guidance on how to adapt implementation support approaches particularly when EBIs cannot be adapted. Future empirical research providing guidance on making practical adaptation decisions are needed.


Assuntos
Serviços de Alimentação/organização & administração , Política de Saúde , Instituições Acadêmicas/organização & administração , Austrália , Humanos
3.
Osteoporos Int ; 29(1): 5-17, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29043392

RESUMO

Osteoporosis is affecting over 200 million people worldwide. Despite available guidelines, care for these patients remains sub-optimal. We developed an osteoporosis tool to address the multiple dimensions of chronic disease management. Findings from its evaluation showed a significant increase from baseline in osteoporosis investigations and treatment, so we are revising this tool to include multiple chronic conditions including an update of evidence about osteoporosis. Our objectives were to conduct a systematic review of osteoporosis interventions in adults at risk for osteoporosis. We searched bibliometric databases for randomized controlled trials (RCTs) in any language evaluating osteoporosis disease management interventions in adults at risk for osteoporosis. Reviewer pairs independently screened citations and full-text articles, extracted data, and assessed risk of bias. Analysis included random effects meta-analysis. Primary outcomes were osteoporosis investigations and treatment, and fragility fractures. Fifty-five RCTs and one companion report were included in the analysis representing 165,703 patients. Our findings from 55 RCTs and 18 sub-group meta-analyses showed that complex implementation interventions with multiple components consisting of at least education + feedback + follow-up significantly increased the initiation of osteoporosis medications, and interventions with at least education + follow-up significantly increased the initiation of osteoporosis investigations. No significant impact was found for any type of intervention to reduce fracture. Complex interventions that include at least education + follow-up or feedback have the most potential for increasing osteoporosis investigations and treatment. Patient education appears to be an important component in osteoporosis disease management.


Assuntos
Osteoporose/diagnóstico , Osteoporose/terapia , Densidade Óssea , Conservadores da Densidade Óssea/uso terapêutico , Gerenciamento Clínico , Uso de Medicamentos/estatística & dados numéricos , Humanos , Osteoporose/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Educação de Pacientes como Assunto/estatística & dados numéricos
4.
Spinal Cord ; 54(1): 29-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26055818

RESUMO

STUDY DESIGN: Cross-sectional survey. OBJECTIVE: To examine the association between psychological characteristics in self-management and probable depression status in individuals with a traumatic spinal cord injury (SCI). SETTING: Community-dwelling individuals with traumatic SCI living across Canada. METHODS: Individuals with SCI were recruited by email via the Rick Hansen Institute as well as an outpatient hospital spinal clinic. Data were collected by self-report using an online survey. Standardized questionnaires were embedded within a larger survey and included the Hospital Anxiety and Depression Scale (HADS), the short version of the Patient Activation Measure (PAM), the Moorong Self-Efficacy Scale (MSES) and the Pearlin-Schooler Mastery Scale (PMS). RESULTS: Individuals with probable depression (n=25) had lower self-efficacy (67.9 vs 94.2, P<0.0001), mastery (18.9 vs 22.9, P<0.0001) and patient activation (60.4 vs 71.6, P<0.0001) as well as higher anxiety (9.0 vs 5.5, P<0.0001), compared with their non-depressed counterparts (n=75). A logistic regression determined that lower self-efficacy and mastery scores as well as less time since injury were associated with depression status (P=0.002; P=0.02 and P=0.02, respectively). Individuals with higher anxiety scores were almost 1.5 times more likely to be depressed, while older age was positively associated with depression status (P=0.016 and P=0.024, respectively). CONCLUSION: Interventions for depression in SCI, including a self-management program, should target factors such as self-efficacy and mastery, which could improve secondary medical complications and overall quality of life.


Assuntos
Depressão/etiologia , Autocuidado/métodos , Traumatismos da Medula Espinal/psicologia , Adulto , Idoso , Estudos Transversais , Feminino , Inquéritos Epidemiológicos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Autoeficácia , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/terapia , Estatísticas não Paramétricas
5.
BJOG ; 122(8): 1119-29, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25316196

RESUMO

OBJECTIVE: To study the dispensing of potentially teratogenic drugs in the 12-month period before as well as during pregnancy in the Netherlands. DESIGN: Population-based study. SETTING: A cohort was constructed using a linkage between the PHARMO Database Network and the Netherlands Perinatal Registry (PRN). POPULATION: A total of 203 962 Dutch pregnancies reported between 1999 and 2007 METHODS: Drug-dispensing information was identified from the PHARMO Database Network for the 12-month period before conception and during pregnancy. Drugs with either a Swedish FASS 'D' classification, an Australian ADEC or American FDA 'D' or 'X' classification were considered potentially teratogenic (n = 202). MEAN OUTCOME MEASURES: Proportion of pregnancies that received potentially teratogenic drugs in the 12-month period before and during pregnancy and specific for the risk category X drugs and newly initiated drugs. RESULTS: Sixteen percent of the pregnancies received a potentially teratogenic drug in the 12-month period before and 5.07% during pregnancy. Doxycycline and paroxetine were most frequently received during pregnancy by 1.01% and 0.85% of women, respectively; 0.66% of the women received a risk category X drug during pregnancy which most frequently consisted of triptorelin (0.25%), norethisterone (0.22%) and simvastatin (0.03%). Fifty-three percent of the women who received a potentially teratogenic drug during pregnancy received this for the first time during the study period. These percentages were heterogeneous between therapeutic drug classes. CONCLUSIONS: Five percent of the pregnancies received a potentially teratogenic drug during pregnancy and 0.66% received a drug from the risk category X. It may be possible to reduce these proportions when reasons for prescription have been explored.


Assuntos
Prescrições de Medicamentos/estatística & dados numéricos , Padrões de Prática Médica/estatística & dados numéricos , Teratogênicos/provisão & distribuição , Adulto , Doxiciclina/administração & dosagem , Feminino , Humanos , Países Baixos/epidemiologia , Noretindrona/administração & dosagem , Paroxetina/administração & dosagem , Gravidez , Sinvastatina/administração & dosagem , Fatores de Tempo , Pamoato de Triptorrelina/administração & dosagem
6.
Diabetologia ; 55(1): 51-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21956710

RESUMO

AIMS/HYPOTHESIS: Several publications suggest an association between certain types of insulin and cancer, but with conflicting results. We investigated whether insulin glargine (A21Gly,B31Arg,B32Arg human insulin) is associated with an increased risk of cancer in a large population-based cohort study. METHODS: Data for this study were obtained from dispensing records from community pharmacies individually linked to hospital discharge records from 2.5 million individuals in the Netherlands. In a cohort of incident users of insulin, the association between insulin glargine and other insulin analogues, respectively, and cancer was analysed in comparison with human insulin using Cox proportional hazard models with cumulative duration of drug use as a time-varying determinant. The first hospital admission with a primary diagnosis of cancer was considered as the main outcome; secondary analyses were performed with specific cancers as outcomes. RESULTS: Of the 19,337 incident insulin users enrolled, 878 developed cancer. Use of insulin glargine was associated with a lower risk of malignancies in general in comparison with human insulin (HR 0.75, 95% CI 0.71, 0.80). In contrast, an increased risk was found for breast cancer (HR 1.58, 95% CI 1.22, 2.05). Dose-response relationships could not be identified. CONCLUSION/INTERPRETATION: Users of insulin glargine and users of other insulin analogues had a lower risk of cancer in general than those using human insulin. Both associations might be a consequence of residual confounding, lack of adherence or competing risk. However, as in previous studies, we demonstrated an increased risk of breast cancer in users of insulin glargine in comparison with users of human insulin.


Assuntos
Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/efeitos adversos , Insulina de Ação Prolongada/efeitos adversos , Insulina Regular Humana/efeitos adversos , Insulina/análogos & derivados , Neoplasias/induzido quimicamente , Neoplasias da Mama/induzido quimicamente , Neoplasias da Mama/complicações , Neoplasias da Mama/epidemiologia , Estudos de Coortes , Serviços Comunitários de Farmácia , Diabetes Mellitus Tipo 2/complicações , Relação Dose-Resposta a Droga , Registros Eletrônicos de Saúde , Feminino , Seguimentos , Humanos , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Incidência , Insulina/administração & dosagem , Insulina/efeitos adversos , Insulina/uso terapêutico , Insulina Glargina , Insulina de Ação Prolongada/administração & dosagem , Insulina de Ação Prolongada/uso terapêutico , Insulina Regular Humana/administração & dosagem , Insulina Regular Humana/uso terapêutico , Masculino , Registro Médico Coordenado , Pessoa de Meia-Idade , Neoplasias/complicações , Neoplasias/epidemiologia , Países Baixos/epidemiologia , Admissão do Paciente , Modelos de Riscos Proporcionais , Risco
7.
Ann Allergy Asthma Immunol ; 108(4): 260-5.e2, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22469446

RESUMO

BACKGROUND: Asthma action plans improve asthma outcomes and are recommended in guidelines. However, delivery by physicians and usage by patients remain low. This may be because of variability in existing plans and a failure to consider visual design and usability factors in plan development. OBJECTIVE: To characterize the variability in both the content and the format of existing plans, and the extent to which their format conforms to evidence-based visual design recommendations. METHODS: We collected plans from the internet, Canadian experts and associations, guidelines, and published trials. We inductively developed analytic criteria for format and content analyses. RESULTS: We collected 69 unique English or French-language adult outpatient plans from around the world. We found large variability in format, and plans fulfilled a mean of only 3.5 out of 8 evidence-based visual design recommendations. Content was also variable, including different descriptions of the baseline clinical state and descriptions and instructions at each "action point" (point recommending a change in treatment). CONCLUSION: Existing plans vary widely in content and format. Accordingly, studies evaluating the effectiveness of action plans may not be directly comparable. Also, visual design may affect usability, uptake, and effectiveness. Our results suggest that this has not been adequately addressed in most plans, and design evidence and experts should be included in future development.


Assuntos
Asma/epidemiologia , Nebulizadores e Vaporizadores/estatística & dados numéricos , Padrões de Prática Médica , Asma/tratamento farmacológico , Canadá , Ensaios Clínicos como Assunto , Atenção à Saúde , Medicina Baseada em Evidências , Feminino , Humanos , Masculino , Guias de Prática Clínica como Assunto , Garantia da Qualidade dos Cuidados de Saúde , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
8.
Support Care Cancer ; 20(3): 641-5, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22072050

RESUMO

PURPOSE: We explored regret in thyroid cancer patients, relating to the decision to accept or reject adjuvant radioactive iodine treatment. METHODS: We studied patients with a recent diagnosis of early stage papillary thyroid carcinoma, in whom treatment decisions on adjuvant radioactive iodine had been finalized. Participants completed a Decision Regret Scale questionnaire. We asked the participants to identify who made the final decision about radioactive iodine treatment. We explored the relationship between decision regret and a) degree of patient involvement in decision-making and b) receipt of radioactive iodine treatment. RESULTS: We included 44 individuals, more than half of whom received adjuvant radioactive iodine treatment (26/44). Decision regret was generally low (mean 22.1, standard deviation [SD] 13.0). Participants reported that the final treatment decision was made by the following: patient and doctor (52.3%, 23/44), completely the patient (27.3%, 12/44), or completely the physician (20.5%, 9/44). Decision regret significantly differed according to who made the final decision: the patient (mean 19.0, SD 11.3), patient and doctor (mean 19.5, SD 7.4), and the doctor (mean 32.9, SD 20.37) (F = 4.569; degrees of freedom = 2, 41; p = 0.016). There was no significant difference in decision regret between patients who received radioactive iodine and those who did not (mean difference -2.5; 95% confidence interval -10.6, 5.6; p = 0.540). CONCLUSION: Thyroid cancer patients who reported being involved in the final treatment decision on adjuvant radioactive iodine had less regret than those who did not.


Assuntos
Radioisótopos do Iodo/uso terapêutico , Participação do Paciente , Satisfação do Paciente , Neoplasias da Glândula Tireoide/radioterapia , Adolescente , Adulto , Tomada de Decisões , Emoções , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Radioterapia Adjuvante , Inquéritos e Questionários , Neoplasias da Glândula Tireoide/cirurgia , Tireoidectomia , Adulto Jovem
9.
Antimicrob Agents Chemother ; 55(6): 2743-54, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21464247

RESUMO

MX-2401 is a semisynthetic calcium-dependent lipopeptide antibiotic (analogue of amphomycin) in preclinical development for the treatment of serious Gram-positive infections. In vitro and in vivo, MX-2401 demonstrates broad-spectrum bactericidal activity against Gram-positive organisms, including antibiotic-resistant strains. The objective of this study was to investigate the mechanism of action of MX-2401 and compare it with that of the lipopeptide daptomycin. The results indicated that although both daptomycin and MX-2401 are in the structural class of Ca²âº-dependent lipopeptide antibiotics, the latter has a different mechanism of action. Specifically, MX-2401 inhibits peptidoglycan synthesis by binding to the substrate undecaprenylphosphate (C55-P), the universal carbohydrate carrier involved in several biosynthetic pathways. This interaction resulted in inhibition, in a dose-dependent manner, of the biosynthesis of the cell wall precursors lipids I and II and the wall teichoic acid precursor lipid III, while daptomycin had no significant effect on these processes. MX-2401 induced very slow membrane depolarization that was observed only at high concentrations. Unlike daptomycin, membrane depolarization by MX-2401 did not correlate with its bactericidal activity and did not affect general membrane permeability. In contrast to daptomycin, MX-2401 had no effect on lipid flip-flop, calcein release, or membrane fusion with 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC)/1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1'-rac-glycerol) (sodium salt) (POPG) liposomes. MX-2401 adopts a more defined structure than daptomycin, presumably to facilitate interaction with C55-P. Mutants resistant to MX-2401 demonstrated low cross-resistance to other antibiotics. Overall, these results provided strong evidence that the mode of action of MX-2401 is unique and different from that of any of the approved antibiotics, including daptomycin.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Lipopeptídeos/farmacologia , Antibacterianos/química , Membrana Celular/efeitos dos fármacos , Permeabilidade da Membrana Celular/efeitos dos fármacos , Daptomicina/química , Daptomicina/farmacologia , Humanos , Lipopeptídeos/química , Staphylococcus/efeitos dos fármacos , Staphylococcus/metabolismo , Uridina Difosfato Ácido N-Acetilmurâmico/análogos & derivados , Uridina Difosfato Ácido N-Acetilmurâmico/biossíntese , Uridina Difosfato Ácido N-Acetilmurâmico/metabolismo
10.
Clin Endocrinol (Oxf) ; 74(4): 419-23, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21198742

RESUMO

In patients with early stage papillary thyroid carcinoma (PTC) who have had a thyroidectomy, the decision must be made to accept or reject radioactive iodine remnant ablation (RRA). Counselling patients about this decision can be challenging, given the medical evidence uncertainties and the complexity of related information. Although physicians are the primary source of medical information for patients considering RRA, some patients have a desire for supplemental information from sources such as the internet. Yet, thyroid cancer resources on the internet are of variable quality, and some may not be applicable to the individual case. We have developed a computerized educational tool [called a decision aid (DA)], directed to patients with early stage papillary thyroid cancer, and intended as an adjunct to physician counselling, to relay evidence-based medical information on disease prognosis and the choice to accept or reject RRA. DAs are tools used to inform patients about available treatment options and have been utilized in oncologic decision-making. We tested our web-based DA in fifty patients with early stage PTC and found that it improved medical knowledge. Furthermore, participants found the technical usability of the tool acceptable. We are currently conducting a randomized controlled trial comparing the use of the DA plus usual care to usual care alone to confirm the educational benefit of the website and examine its impact on the decision-making process. In the future, DAs may play an expanded role as an adjunct to physician counselling in the care of patients with thyroid cancer.


Assuntos
Tomada de Decisões , Radioisótopos do Iodo/uso terapêutico , Educação de Pacientes como Assunto/métodos , Adolescente , Adulto , Carcinoma , Carcinoma Papilar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Software , Câncer Papilífero da Tireoide , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/terapia , Tireoidectomia , Adulto Jovem
11.
Br J Dermatol ; 164(2): 238-44, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20716214

RESUMO

Most of the publications on isotretinoin, pregnancy and compliance with the pregnancy prevention programme (PPP) originate from North America. Information specific for the European situation is very limited. The aim of this study was to identify publications describing the use of isotretinoin in humans and the compliance with the PPP in Europe, a systematic search in Medline and Embase was conducted using the terms 'isotretinoin, pregnancy (and Europe)'. Furthermore, a manual search in publications was performed. A total of 17 publications were identified. Publications consisted of case reports of exposed pregnancies, surveys among dermatologists or pharmacists and database studies evaluating compliance with the PPP. The studies and surveys dealt with groups of patients exposed to isotretinoin before or during pregnancy and/or compliance with the isotretinoin PPP. Where the information was provided, in 6-26% of cases isotretinoin was prescribed in full accordance with the PPP. Pregnancy incidence was seen in 0·2-1·0 per 1000 women of childbearing age using isotretinoin. Between 65% and 87% of these pregnancies were terminated. This review of studies in Europe performed to date shows failures in the implementation of the PPP. Therefore, the isotretinoin PPP must be scrutinized to identify whether new measures should be taken or whether the failures in the implementation need to be corrected. New measures should take into account the definition of the ultimate goal of a PPP and the acceptable burden. In the meantime, stakeholders could make a start with adjustments in the implementation of the PPP by taking responsibility and enhancing the performance by explicit instructions, monitoring the performance and adjusting, if necessary.


Assuntos
Anormalidades Induzidas por Medicamentos/prevenção & controle , Fármacos Dermatológicos/efeitos adversos , Fidelidade a Diretrizes , Isotretinoína/efeitos adversos , Teratogênicos , Acne Vulgar/tratamento farmacológico , Adolescente , Adulto , Criança , Europa (Continente) , Feminino , Inquéritos Epidemiológicos , Humanos , Isotretinoína/uso terapêutico , Pessoa de Meia-Idade , Gravidez , Adulto Jovem
12.
Eur Biophys J ; 40(3): 221-34, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21082179

RESUMO

Filamentous bacteriophages (filamentous bacterial viruses or Inovirus) are simple and well-characterised macromolecular assemblies that are widely used in molecular biology and biophysics, both as paradigms for studying basic biological questions and as practical tools in areas as diverse as immunology and solid-state physics. The strains fd, M13 and f1 are virtually identical filamentous phages that infect bacteria expressing F-pili, and are sometimes grouped as the Ff phages. For historical reasons fd has often been used for structural studies, but M13 and f1 are more often used for biological experiments. Many other strains have been identified that are genetically quite distinct from Ff and yet have a similar molecular structure and life cycle. One of these, Pf1, gives the highest resolution X-ray fibre diffraction patterns known for filamentous bacteriophage. These diffraction patterns have been used in the past to derive a molecular model for the structure of the phage. Solid-state NMR experiments have been used in separate studies to derive a significantly different model of Pf1. Here we combine previously published X-ray fibre diffraction data and solid-state NMR data to give a consensus structure model for Pf1 filamentous bacteriophage, and we discuss the implications of this model for assembly of the phage at the bacterial membrane.


Assuntos
Bacteriófago Pf1/química , Espectroscopia de Ressonância Magnética/métodos , Difração de Raios X/métodos , Bacteriófago Pf1/metabolismo , Capsídeo/química , Proteínas do Capsídeo/química , Membrana Celular/química , Modelos Moleculares , Conformação Proteica , Pseudomonas/virologia , Proteínas Virais/química , Vírion/química
13.
Nat Med ; 5(12): 1375-82, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10581079

RESUMO

Elucidating the cellular immune response to infectious agents is a prerequisite for understanding disease pathogenesis and designing effective vaccines. In the identification of microbial T-cell epitopes, the availability of purified or recombinant bacterial proteins has been a chief limiting factor. In chronic infectious diseases such as Lyme disease, immune-mediated damage may add to the effects of direct infection by means of molecular mimicry to tissue autoantigens. Here, we describe a new method to effectively identify both microbial epitopes and candidate autoantigens. The approach combines data acquisition by positional scanning peptide combinatorial libraries and biometric data analysis by generation of scoring matrices. In a patient with chronic neuroborreliosis, we show that this strategy leads to the identification of potentially relevant T-cell targets derived from both Borrelia burgdorferi and the host. We also found that the antigen specificity of a single T-cell clone can be degenerate and yet the clone can preferentially recognize different peptides derived from the same organism, thus demonstrating that flexibility in T-cell recognition does not preclude specificity. This approach has potential applications in the identification of ligands in infectious diseases, tumors and autoimmune diseases.


Assuntos
Epitopos/isolamento & purificação , Doença de Lyme/imunologia , Mimetismo Molecular/imunologia , Linfócitos T/imunologia , Adulto , Sequência de Aminoácidos , Antígenos de Bactérias/genética , Antígenos de Bactérias/isolamento & purificação , Autoantígenos/genética , Autoantígenos/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/imunologia , Proteínas de Bactérias/isolamento & purificação , Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/imunologia , Células Clonais , Epitopos/genética , Humanos , Imunidade Celular , Técnicas In Vitro , Doença de Lyme/genética , Neuroborreliose de Lyme/genética , Neuroborreliose de Lyme/imunologia , Ativação Linfocitária , Masculino , Mimetismo Molecular/genética , Polimorfismo Conformacional de Fita Simples
14.
J Exp Med ; 187(7): 1113-22, 1998 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-9529327

RESUMO

The mechanism by which HIV-1 induces CD4(+) T cell death is not known. A fundamental issue is whether HIV-1 primarily induces direct killing of infected cells or indirectly causes death of uninfected bystander cells. This question was studied using a reporter virus system in which infected cells are marked with the cell surface protein placental alkaline phosphatase (PLAP). Infection by HIV-PLAP of peripheral blood mononuclear cells (PBMCs) and T cell lines leads to rapid depletion of CD4(+) T cells and induction of apoptosis. The great majority of HIV-induced T cell death in vitro involves direct loss of infected cells rather than indirect effects on uninfected bystander cells. Because of its proposed role in HIV-induced cell death, we also examined the Fas (CD95/Apo1) pathway in killing of T cells by HIV-1. Infected PBMCs or CEM cells display no increase in surface Fas relative to uninfected cells. In addition, HIV-1 kills CEM and Jurkat T cells in the presence of a caspase inhibitor that completely blocks Fas-mediated apoptosis. HIV-1 also depletes CD4+ T cells in PBMCs from patients who have a genetically defective Fas pathway. These results suggest that HIV-1 induces direct apoptosis of infected cells and kills T cells by a Fas-independent mechanism.


Assuntos
Apoptose/fisiologia , Linfócitos T CD4-Positivos/metabolismo , HIV-1/metabolismo , Receptor fas/metabolismo , Fosfatase Alcalina , Anticorpos/imunologia , Anticorpos/farmacologia , Biomarcadores/química , Linfócitos T CD4-Positivos/virologia , Inibidores de Cisteína Proteinase/farmacologia , Citometria de Fluxo , Proteínas Ligadas por GPI , HIV-1/genética , Humanos , Isoenzimas/metabolismo , Células Tumorais Cultivadas , Receptor fas/imunologia
15.
J Exp Med ; 181(1): 297-306, 1995 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-7807009

RESUMO

The latency-associated transcript (LAT) is the only herpes simplex virus (HSV) gene product detectable in latently infected humans and animals. In this report, we show that a 624-bp deletion in the promoter of the HSV-2 LAT had no discernable effect on viral growth in tissue culture or in acute genital infection of guinea pigs, but impaired LAT accumulation and led to a marked decrease in spontaneous genital recurrences when compared with the behavior of wild-type and rescuant strains. Differences in the ability of the mutant to replicate, or in how readily it established or maintained latency did not account for this finding. Thus, HSV LAT expression facilitates the spontaneous reactivation of latent virus.


Assuntos
Regulação Viral da Expressão Gênica , Herpes Genital/microbiologia , Herpesvirus Humano 2/genética , Latência Viral , Doença Aguda , Animais , Sequência de Bases , Primers do DNA/química , DNA Viral/genética , Genes Virais , Cobaias , Herpesvirus Humano 2/patogenicidade , Dados de Sequência Molecular , Regiões Promotoras Genéticas , Recidiva , Mapeamento por Restrição , Proteínas Estruturais Virais/genética , Replicação Viral
16.
Age Ageing ; 38(6): 724-30, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19767629

RESUMO

BACKGROUND: falls are the leading causes of accidental death and fragility fractures in older adults. Interventions that assess and reduce falls risk are underutilised. OBJECTIVE: to evaluate the impact of a multifaceted community-based programme aimed at optimising evidence-based management of patients at risk for fall-related fractures. DESIGN: this was a randomised trial performed from 2003 to 2006. SETTING: community-based intervention in Ontario, Canada. PARTICIPANTS: eligible patients were community-dwelling, aged > or =55 years and identified to be at risk for fall-related fractures. A total of 201 patients were allocated to the intervention group or to usual care. INTERVENTION: components of the intervention included assessment of falls risk, functional status and home environment, and patient education. MEASUREMENTS: primary outcome was the implementation of appropriate falls risk assessment at 6 months. Secondary outcomes included falls and fractures at 6 and 12 months. RESULTS: the mean age of participants was 72 years, and 41% had fallen with injury in the previous year. Compared to usual care, the intervention increased the number of referrals made to physiotherapy [21% (21/101) vs 6.0% (6/100); relative risk (RR) 3.47, 95% confidence interval (CI) 1.46-8.22] and occupational therapy [15% (15/101) vs 0%; RR 30.7, 95% CI 1.86 to >500]. At 12 months, the number of falls in the intervention group was greater than in the usual care group [23% (23/101) vs 11% (11/100); RR 2.07, 95% CI 1.07-4.02]. CONCLUSIONS: compared to usual care, a multi-faceted intervention increased referrals to physiotherapy and occupational therapy but did not reduce risk of falls. Similar falls reduction interventions cannot be recommended based on the results of this study.


Assuntos
Acidentes por Quedas/prevenção & controle , Atividades Cotidianas , Gestão de Riscos/organização & administração , Idoso , Idoso de 80 Anos ou mais , Medicina Baseada em Evidências , Feminino , Avaliação Geriátrica , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Ontário , Avaliação de Resultados em Cuidados de Saúde , Educação de Pacientes como Assunto , Fatores de Risco
17.
Curr Oncol ; 26(2): 124-136, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31043815

RESUMO

Background: Patient education materials (pems) are frequently used to help patients make cancer screening decisions. However, because pems are typically developed by experts, they might inadequately address patient barriers to screening. We co-created, with patients, a prostate cancer (pca) screening pem, and we compared how the co-created pem and a pem developed by experts affected decisional conflict and screening intention in patients. Methods: We identified and used patient barriers to pca screening to co-create a pca screening pem with patients, clinicians, and researchers. We then conducted a parallel-group randomized controlled trial with men 40 years of age and older in Ontario to compare decisional conflict and intention about pca screening after those men had viewed the co-created pem (intervention) or an expert-created pem (control). Participants were randomized using dynamic block randomization, and the study team was blinded to the allocation. Results: Of 287 participants randomized to exposure to the co-created pem, 230 were analyzed, and of 287 randomized to exposure to the expert-created pem, 223 were analyzed. After pem exposure, intervention and control participants did not differ significantly in Decisional Conflict Scale scores [mean difference: 0.37 ± 1.23; 95% confidence interval (ci): -2.05 to 2.79]; in sure (Sure of myself, Understand information, Risk-benefit ratio, or Encouragement) scores (odds ratio: 0.75; 95% ci: 0.52 to 1.08); or in screening intention (mean difference: 0.09 ± 0.08; 95% ci: -0.06 to 0.24]). Conclusions: The effectiveness of the co-created pem did not differ from that of the pem developed by experts. Thus, pem developers should choose the method that best fits their goals and resources.


Assuntos
Detecção Precoce de Câncer , Programas de Rastreamento , Educação de Pacientes como Assunto , Participação do Paciente , Neoplasias da Próstata/diagnóstico , Adulto , Idoso , Tomada de Decisões , Humanos , Masculino , Pessoa de Meia-Idade , Ontário , Pesquisa Qualitativa
18.
N Engl J Med ; 352(22): 2271-84, 2005 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-15930418

RESUMO

BACKGROUND: The incidence and severity of herpes zoster and postherpetic neuralgia increase with age in association with a progressive decline in cell-mediated immunity to varicella-zoster virus (VZV). We tested the hypothesis that vaccination against VZV would decrease the incidence, severity, or both of herpes zoster and postherpetic neuralgia among older adults. METHODS: We enrolled 38,546 adults 60 years of age or older in a randomized, double-blind, placebo-controlled trial of an investigational live attenuated Oka/Merck VZV vaccine ("zoster vaccine"). Herpes zoster was diagnosed according to clinical and laboratory criteria. The pain and discomfort associated with herpes zoster were measured repeatedly for six months. The primary end point was the burden of illness due to herpes zoster, a measure affected by the incidence, severity, and duration of the associated pain and discomfort. The secondary end point was the incidence of postherpetic neuralgia. RESULTS: More than 95 percent of the subjects continued in the study to its completion, with a median of 3.12 years of surveillance for herpes zoster. A total of 957 confirmed cases of herpes zoster (315 among vaccine recipients and 642 among placebo recipients) and 107 cases of postherpetic neuralgia (27 among vaccine recipients and 80 among placebo recipients) were included in the efficacy analysis. The use of the zoster vaccine reduced the burden of illness due to herpes zoster by 61.1 percent (P<0.001), reduced the incidence of postherpetic neuralgia by 66.5 percent (P<0.001), and reduced the incidence of herpes zoster by 51.3 percent (P<0.001). Reactions at the injection site were more frequent among vaccine recipients but were generally mild. CONCLUSIONS: The zoster vaccine markedly reduced morbidity from herpes zoster and postherpetic neuralgia among older adults.


Assuntos
Vacina contra Varicela , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Neuralgia/prevenção & controle , Idoso , Vacina contra Varicela/efeitos adversos , Vacina contra Varicela/imunologia , Efeitos Psicossociais da Doença , Método Duplo-Cego , Feminino , Seguimentos , Herpes Zoster/complicações , Herpes Zoster/epidemiologia , Herpesvirus Humano 3/imunologia , Humanos , Memória Imunológica , Incidência , Masculino , Pessoa de Meia-Idade , Neuralgia/virologia , Vacinas Atenuadas/efeitos adversos , Vacinas Atenuadas/imunologia , Ativação Viral
19.
J Clin Invest ; 86(1): 235-41, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2365817

RESUMO

Only one herpes simplex virus type 1 (HSV-1) gene is expressed in sensory neurons of latently infected animals and humans, yielding two RNAs, called latency-associated transcripts (LATs). The LATs appear to modulate virus reactivation. In mice and rabbits the 5' origins, kinetics of synthesis, and splicing pattern of the LATs are well established. Because these details of LAT structure and expression have not been defined in humans, we sought to do so. Using primer extension and Northern hybridization analyses, we demonstrate that in human trigeminal ganglia, the smaller (1.35 kb) HSV-1 transcript differs from the larger (1.85 kb) LAT by excision of an intron near its 5' end; they are otherwise colinear, and 5' coterminal. In infected cells only the 1.85 kb LAT is detected. Its expression is inhibited by cycloheximide or acyclovir, indicating this LAT is synthesized late in the viral replicative cycle. All of these features of the LATs in humans are consistent with those reported in rabbits and mice and further validate the animal models of human HSV-1 infection.


Assuntos
Herpes Simples/genética , RNA Viral/genética , Gânglio Trigeminal/microbiologia , Aciclovir/farmacologia , Animais , Sequência de Bases , Northern Blotting , Doença Crônica , Expressão Gênica/efeitos dos fármacos , Humanos , Dados de Sequência Molecular , Sondas de Oligonucleotídeos , Splicing de RNA , RNA Mensageiro/genética , Transcrição Gênica , Células Vero
20.
J Clin Invest ; 101(3): 643-9, 1998 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-9449698

RESUMO

To further understand the role of cytokine responses in symptom formation and host defenses in influenza infection, we determined the levels of IL-1beta, IL-2, IL-6, IL-8, IFN-alpha, TGF-beta, and TNF-alpha in nasal lavage fluid, plasma, and serum obtained serially from 19 volunteers experimentally infected with influenza A/Texas/36/91 (H1N1) and correlated these levels with various measures of infection and illness severity. We found that IL-6 and IFN-alpha levels in nasal lavage fluids peaked early (day 2) and correlated directly with viral titers, temperature, mucus production, and symptom scores. IL-6 elevations were also found in the circulation at this time point. In contrast, TNF-alpha responses peaked later (day 3 in plasma, day 4 in nasal fluids), when viral shedding and symptoms were subsiding. Similarly, IL-8 peaked late in the illness course (days 4-6) and correlated only with lower respiratory symptoms, which also occurred late. None of IL-1beta, IL-2, or TGF-beta levels increased significantly. These data implicate IL-6 and IFN-alpha as key factors both in symptom formation and host defense in influenza.


Assuntos
Citocinas/imunologia , Vírus da Influenza A/imunologia , Influenza Humana/imunologia , Citocinas/sangue , Feminino , Humanos , Influenza Humana/sangue , Influenza Humana/fisiopatologia , Masculino , Líquido da Lavagem Nasal/imunologia , Voluntários
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