RESUMO
Mechanisms responsible for neuroattenuation of herpes simplex virus (HSV) have been defined previously by studies of mutant viruses in cultured cells. The hypothesis that null mutations in host genes can override the attenuated phenotype of null mutations in certain viral genes was tested. Mutants such as those in infected cell protein (ICP) 0, thymidine kinase, ribonucleotide reductase, virion host shutoff, and ICP34.5 are reduced in their capacity to replicate in nondividing cells in culture and in vivo. The replication of these viruses was examined in eyes and trigeminal ganglia for 1-7 d after corneal inoculation in mice with null mutations (-/-) in interferon receptors (IFNR) for type I IFNs (IFN-alpha/betaR), type II IFN (IFN-gammaR), and both type I and type II IFNs (IFN-alpha/beta/gammaR). Viral titers in eyes and ganglia of IFN-gammaR-/- mice were not significantly different from congenic controls. However, in IFN-alpha/betaR-/- or IFN-alpha/beta/gammaR-/- mice, growth of all mutants, including those with significantly impaired growth in cell culture, was enhanced by up to 1,000-fold in eyes and trigeminal ganglia. Blepharitis and clinical signs of infection were evident in IFN-alpha/betaR-/- and IFN-alpha/beta/gammaR-/- but not control mice for all viruses. Also, IFNs were shown to significantly reduce productive infection of, and spread from intact, but not scarified, corneas. Particularly striking was restoration of near-normal trigeminal ganglion replication and neurovirulence of an ICP34.5 mutant in IFN-alpha/betaR-/- mice. These data show that IFNs play a major role in limiting mutant and wild-type HSV replication in the cornea and in the nervous system. In addition, the in vivo target of ICP34.5 may be host IFN responses. These experiments demonstrate an unsuspected role for host factors in defining the phenotypes of some HSV mutants in vivo. The phenotypes of mutant viruses therefore cannot be interpreted based solely upon studies in cell culture but must be considered carefully in the context of host factors that may define the in vivo phenotype.
Assuntos
Proteínas Imediatamente Precoces/fisiologia , Interferons/fisiologia , Ceratite Herpética/virologia , Receptores de Interferon/fisiologia , Ribonucleotídeo Redutases/fisiologia , Simplexvirus/genética , Timidina Quinase/fisiologia , Proteínas Virais/fisiologia , Animais , Chlorocebus aethiops , Córnea/virologia , Lesões da Córnea , Proteínas Imediatamente Precoces/genética , Imunocompetência , Interferon-alfa/deficiência , Interferon-alfa/genética , Interferon-alfa/fisiologia , Interferon beta/deficiência , Interferon beta/genética , Interferon beta/fisiologia , Interferon gama/deficiência , Interferon gama/genética , Interferon gama/fisiologia , Interferons/deficiência , Interferons/genética , Ceratite Herpética/fisiopatologia , Camundongos , Camundongos Knockout , Fenótipo , Receptor de Interferon alfa e beta , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Ribonucleases , Ribonucleotídeo Redutases/genética , Simplexvirus/efeitos dos fármacos , Simplexvirus/isolamento & purificação , Simplexvirus/patogenicidade , Simplexvirus/fisiologia , Timidina Quinase/genética , Gânglio Trigeminal/virologia , Ubiquitina-Proteína Ligases , Células Vero , Proteínas Virais/genética , Virulência/genética , Replicação Viral/genética , Receptor de Interferon gamaRESUMO
To examine the effects of intensive patient and/or physician diabetes education on patient health outcomes, a controlled trial was conducted in which internal medicine residents and their 532 diabetic patients were randomly assigned to: routine care; patient education; physician education; or both patient and physician education. Patient outcome data were analyzed either by analysis of covariance on post intervention values (2-hour post-prandial plasma glucose [PPG]; body weight [BW]; blood pressure [BP]; or analysis of variance conducted on change values (fasting plasma glucose [FPG] and glycosylated hemoglobin [A1Hgb]). After patient education, significant improvements were observed in FPG, A1Hgb, BW, and systolic and diastolic BP. Physician education resulted in significant decreases in FPG, A1Hgb and BW. The combination of patient plus physician education resulted in the greatest improvements in patients' health outcomes including FPG, A1Hgb, PPG, BW and diastolic BP. Adjusted systolic BPs were not significantly different in the two groups. While these physiologic improvements were statistically and probably clinically significant, hyperglycemia and obesity still persisted. Thus, achieving optimal patient outcomes for a chronic disease like diabetes mellitus may require a greater or more effective use of resources than currently estimated.
Assuntos
Diabetes Mellitus , Medicina Interna/educação , Internato e Residência , Educação de Pacientes como Assunto , Ensaios Clínicos como Assunto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Processos e Resultados em Cuidados de Saúde , Distribuição AleatóriaRESUMO
The Diabetes Education Study (DIABEDS) was a randomized, controlled trial of the effects of patient and physician education. This article describes a systematic education program for diabetes patients and its effects on patient knowledge, skills, self-care behaviors, and relevant physiologic outcomes. The original sample consisted of 532 diabetes patients from the general medicine clinic at an urban medical center. Patients were predominantly elderly, black women with non-insulin-dependent diabetes mellitus of long duration. Patients randomly assigned to experimental groups (N = 263) were offered up to seven modules of patient education. Each content area module contained didactic instruction (lecture, discussion, audio-visual presentation), skill exercises (demonstration, practice, feedback), and behavioral modification techniques (goal setting, contracting, regular follow-up). Two hundred seventy-five patients remained in the study throughout baseline, intervention, and postintervention periods (August 1978 to July 1982). Despite the requirement that patients demonstrate mastery of educational objectives for each module, postintervention assessment 11-14 mo after instruction showed only rare differences between experimental and control patients in diabetes knowledge. However, statistically significant group differences in self-care skills and compliance behaviors were relatively more numerous. Experimental group patients experienced significantly greater reductions in fasting blood glucose (-27.5 mg/dl versus -2.8 mg/dl, P less than 0.05) and glycosylated hemoglobin (-0.43% versus + 0.35%, P less than 0.05) as compared with control subjects. Patient education also had similar effects on body weight, blood pressure, and serum creatinine. Continued follow-up is planned for DIABEDS patients to determine the longevity of effects and subsequent impact on emergency room visits and hospitalization.