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Background: Internal medicine residency programs have increased the time devoted to ambulatory medicine and the range of nonmedical areas in which expertise is expected. Whether existing teaching locations can provide [...]

Zidovudine appears as safe and effective when given twice daily, rather than six times daily, for HIV infection. Researchers found that the more convenient dosing regimen and the conventional regimen produced similar rates of side effects and therapeutic benefits.

A number of laboratories throughout the world are attempting to develop a vaccine against the human immunodeficiency virus (HIV), the causative agent in AIDS. Animal models are being developed, but 'phase I data' about the safety of an HIV vaccine in humans has been limited. The National Institute of Allergy and Infectious Disease Acquired Immunodeficiency Syndrome Vaccine Clinical Trials Network (NIAID) has begun human trials of recombinant envelope glycoprotein 160 (rgp160), an HIV subunit vaccine. A total of 67 individuals who were healthy, HIV-negative, and at low risk for acquiring HIV, completed the study. The subjects were subdivided into four groups who received: a placebo; hepatitis B vaccine; rgp160 at 40 micrograms; or rgp160 at 80 micrograms. Injections were given at 0, 30, and 180 days; 52 of the 67 subjects received an injection again at day 540. The injections were generally well-tolerated; no significant immune function depression was seen in any of the subjects. Antibodies against HIV were detected by the Western blot assay in subjects who had received rgp160, often after the second dose, and quite frequently after the third. An issue of greater interest than antibody production is the ability of the vaccine to confer immunity against HIV, as measured by ability of the patients' sera to neutralize the virus or to induce complement immune activity. Neutralizing activity was seen in 5 of the 24 rgp160 patients and complement enhancement was observed in 6 of the 24 (3 of these subjects had both neutralizing activity and complement enhancement). It is concluded that the rgp160 HIV vaccine is safe and well-tolerated, but its efficacy at the doses studied is limited. Studies of higher doses of this vaccine are warranted. (Consumer Summary produced by Reliance Medical Information, Inc.)

How significant are viral infections in exacerbations of chronic obstructive pulmonary disease (COPD)? How might this affect treatment? * Although bacterial infections are believed to be the leading cause of [...]

Human herpesviruses can cause acute and recurrent disease. The seven pathogenic human herpesviruses include the following: herpes simplex type 1 (HSV-1), herpes simplex type 2 (HSV-2), varicella-zoster virus (VZV), Epstein-Barr [...]

Background: Respiratory tract viral infections (RTVIs) have been identified frequently in association with asthma exacerbations in children, but few studies have shown similar rates of viral infections in adults with asthma. Further studies using newer diagnostic techniques to evaluate the frequency of RTVIs in adults with acute exacerbations of asthma need to be performed. Methods: Twenty-nine asthmatic adults were recruited from the pulmonary clinic of an urban county hospital and were followed up in a longitudinal cohort study for signs and symptoms of asthma and RTVI. One hundred twenty-two asthmatic adults presenting to the emergency department (ED) of the same hospital with acute symptoms of asthma underwent evaluation for RTVI in a cross-sectional prevalence study. In both studies, respiratory secretions and paired serum samples were collected from subjects with acute wheezing episodes and evaluated using virus culture, serologic testing, and reverse transcription--polymerase chain reaction (RT-PCR). Results: In the longitudinal cohort study, 138 respiratory illnesses, of which 87 were asthma exacerbations, were evaluated; 41% of all illnesses and 44% of asthma exacerbations were associated with an RTVI. In the ED study, 148 asthma exacerbations were evaluated; 55% were associated with an RTVI. An RTVI was identified in 21 (50%) of 42 of the subjects hospitalized in the ED study. Picornaviruses (rhinoviruses), coronaviruses, and influenza viruses were the most commonly identified causes of RTVI. Forty-six (60%) of the 77 picornavirus infections and 22 (71%) of the 31 coronavirus infections were identified only using RT-PCR. Conclusions: Asthmatic exacerbations in adults are frequently associated with an RTVI. Identification of such infections often requires newer diagnostic methods, such as virus-specific RT-PCR. The high frequency of RTVIs identified in association with asthmatic exacerbations in adults from the inner city suggests that strategies for the prevention of RTVI should be targeted toward this population. Arch Intern Med. 1998;158:2453-2459