Pneumocystis carinii pneumonia is one of the most frequent infectious complications in patients with the acquired immunodeficiency syndrome (AIDS). A prospective trial was initiated to compare azidothymidine alone with azidothymidine plus aerosolized pentamidine as a secondary prophylaxis for pneumocystis carinii pneumonia. 27 patients (24 male, three female, average age 39 years) were enrolled, 14 patients receiving azidothymidine and pentamidine aerosol and 13 azidothymidine alone. After 166 days of follow-up, this trial had to be terminated prematurely, since the efficacy of pentamidine aerosol in the prevention of pneumocystis carinii pneumonia was clearly demonstrated in two recently published studies. Two patients died during the study period, one in either group, but neither due to pneumocystis carinii pneumonia. Two patients developed histologically proven pneumocystis carinii pneumonia; both patients were allocated to the azidothymidine arm. Pneumocystis carinii pneumonia was suspected clinically but not proven in four patients, three were randomized in the azidothymidine arm. Pentamidine was well tolerated and produced no severe side effects. The sample size is too small to draw definitive conclusions concerning the efficacy of pentamidine aerosol in AIDS patients.

Acquired Immunodeficiency Syndrome↗

PubMed1990

[Meaningful combinations of chemotherapeutic agents].

It is frequently assumed that, in general, combinations of antibiotics and similar chemotherapeutic agents are more efficient than the single chemotherapeutic, and that they can be combined without disadvantages for the activity of the single component. However, the specific properties of the combined substances, such as their antimicrobial spectrum and resistance, their pharmacokinetics and side effects, as well as their physical properties and formulation, have an enormous impact on the activity of combined chemotherapeutics. They may lead to an advantageous, but also to an indifferent or diminished activity of the combination in patients. Some of the important requirements for an advantageous combination of antibiotics and similarly functioning compounds will be reviewed and ways of avoiding mistakes are described.

Animals↗

PubMed1990

Changing patient management: what influences the practicing pediatrician?

To explore some determinants of physicians' decisions to change practice habits, we posed three questions: To what extent are some particular innovations diffused among office-based primary care physicians? What characterizes the physicians who have adopted these innovations? And, what caused them to change their behavior and adopt the innovations? Three "markers," recent innovation in medical practice, were chosen using an expert consensus technique. A telephone survey of 200 office-based pediatricians was conducted, and the physicians were asked whether or not they used the following three innovations in medical practice: continuous rather than intermittent phenobarbital for the prevention of febrile seizures, glycosylated hemoglobin measurement in the management of diabetes, and slow release theophylline in the management of asthma. The questionnaire was completed by 156 pediatricians. Of the 110 pediatricians who cared for diabetics, 73% used glycosylated hemoglobin measurement; of the 145 who saw patients with febrile seizures, 77% prescribed the continuous use of phenobarbital (if they used it at all); and, of the 152 pediatricians who cared for asthmatics, 86% reported using slow-release theophylline. The characteristics significantly associated with using the innovations were board certification, group rather than solo practice, teaching, medically related publications, academic appointment, younger age, and caring for a greater number of patients per week. For two of the innovations, discussion with a colleague was the most important source of information leading to a change of practice. The subjects cited local specialists as the colleagues who most often sparked the adoption of an innovation.

Biomarkers↗

PubMed1989

Mucocutaneous plasmacytomas in dogs: 75 cases (1980-1987).

Mucocutaneous plasmacytomas were diagnosed in 75 dogs. Medical records and communication with owners and referring veterinarians provided information regarding location and description of the tumor, clinicopathologic data, treatment, and postoperative status of the dogs. Males and females were equally represented, and most dogs were aged adults (mean, 9.7 years). Tumors developed most commonly in the mouth, on the feet or trunk, and in the ears. Plasmacytomas were confined to the skin and mucosa in 70 dogs. Two dogs had disseminated lymphoid neoplasia, and 1 dog developed cutaneous plasmacytoma during clinical remission of lymphosarcoma. Two dogs had multiple myeloma, which was diagnosed concurrently or within a few weeks of diagnosis of the cutaneous tumor. Multiple plasmacytomas were found in 10 dogs but were not associated with clinical signs of generalized disease. Tumors did not recur after surgical excision. Clinicopathologic values, when determined, were normal in all dogs with localized plasmacytomas.

Animals↗

PubMed1989

Health science information management and continuing education of physicians. A survey of U.S. primary care practitioners and their opinion leaders.

PURPOSE: To identify self-perceived problems in managing science information needs of U.S. primary practitioners and their opinion leaders. SAMPLE: A two-stage random sample of the American Medical Association's "Masterlist of Physicians" to identify 625 office-based physicians, including general practice, family practice, internal medicine, obstetrics and gynecology, and pediatrics, and 100 physician opinion leaders. DATA COLLECTION: A formal telephone survey was completed for 79% of practitioners and 90% of opinion leaders sampled, using a pretested instrument applied by trained telephone surveyors. RESULTS OF DATA ANALYSIS: Both practitioners and opinion leaders claimed that published reviews were the most useful means of identifying their information needs. When asked about use of six recent clinical advances, that is, "markers," for example, hemoglobin-A1C for diabetic control, as many as one fifth to one half were not using or were not aware of such an advance. Less than 1 in 3 practitioners personally searched the literature when information was needed; 2 in 3 claimed literature volume was unmanageable; 9 of 10 practitioners and opinion leaders assessed the scientific value of literature obtained, primarily from their own experience, with less than 1 in 10 contacting research methods specialists. Respondents suggested various innovations to better manage their science information needs in the future. CONCLUSIONS: Primary practitioners require substantial help in meeting current science information needs. Increase in such resources as "validated reviews" or "expert networks" might help meet these needs.

Education, Medical, Continuing↗

PubMed1989

Comparative study of Clostridium difficile toxin A and cholera toxin in rabbit ileum.

The purpose of this study was to compare the effects of Clostridium difficile toxin A and cholera toxin on fluid secretion, intestinal permeability, and arachidonate metabolites in rabbit ileum. Injection of 25 micrograms of either purified toxin into 10-cm ileal loops caused significant increases in fluid secretion and intestinal permeability to mannitol as well as release of prostaglandin E2 into the lumen. Toxin A, but not cholera toxin, caused a severe inflammatory reaction of the lamina propria and necrosis of enterocytes as well as increased release of leukotriene B4. The toxin A-mediated increases in prostaglandin E2 and leukotriene B4 could be blocked by prior instillation of 10 mg of 5-aminosalicylic acid into ileal loops. 5-Aminosalicylic acid also significantly diminished the expected increase in mannitol permeability after both toxins, but had no significant inhibitory effect on fluid secretion or, in the case of toxin A, intestinal inflammation. Our results indicate that C. difficile and cholera enterotoxins differ substantially in their effects on the rabbit intestine. Clostridium difficile toxin A, an inflammatory toxin, produces a striking infiltration of the lamina propria with neutrophils that is associated with increased release of leukotriene B4. In contrast, cholera toxin does not cause inflammation or leukotriene B4 release. Increased release of prostaglandin E2 occurs after exposure to both toxins and appears to be correlated with increased intestinal permeability.

Animals↗

PubMed1989

Neuron-specific enolase and retinoblastoma. Clinicopathologic correlations.

Neuron-specific enolase (a glycolytic, ubiquitous, intracellular enzyme) has recently been reported to be detectable in the aqueous humor of eyes containing retinoblastoma. Aqueous humor from 17 patients with histologically proven retinoblastoma was assayed for the presence of neuron-specific enolase (NSE). NSE was detectable in 17 out of 17 patients with levels between 619 and 60,000 ng/ml. A multitude of clinocopathological parameters were examined for statistically significant correlations with levels of aqueous humor NSE. This investigation demonstrated that only two parameters, the presence of tumor invasion into the anterior chamber, and inflammation significantly correlated with aqueous NSE levels. Histological parameters which did not correlate with aqueous NSE levels included tumor necrosis, calcification, Flexner-Wintersteiner rosettes, exophytic/endophytic tumor type, tumor extent relative to the equator, and optic nerve/choroidal invasion. Clinical parameters which showed no correlation included patient sex (M/F), enucleation age, presentation age, family history, laterality, prior treatment, and presence of metastatic disease. Neuron-specific enolase is present in the anterior chamber of eyes enucleated for retinoblastoma, but additional testing is necessary to determine the normal levels of neuron-specific enolase in children's eyes and the levels in eyes with lesions simulating retinoblastoma.

Anterior Chamber↗

PubMed1989

Infection of brain cells by diverse human immunodeficiency virus isolates: role of CD4 as receptor.

Cell lines originally derived from malignant tumours of the brain were infected by diverse human immunodeficiency virus types 1 and 2 (HIV-1 and HIV-2) isolates. By surface immunofluorescence it was shown that susceptible cells did not bear the CD4 antigen. They were also non-permissive for the formation of plaques by vesicular stomatitis virus pseudotypes and did not form syncytia with HIV-producing cells. Virus production was of low titre, and reverse transcriptase and the p24 antigen were consistently undetectable in the culture supernatants. Output virus could be detected by cocultivation with a sensitive T cell line, C8166, by the culture of supernatant medium with T cells and by detection of proviral HIV DNA after amplification. A higher multiplicity of input virus was required to establish a brain cell infection than was required for T lymphocytes or monocytes. Some HIV-susceptible brain cells contained mRNA for CD4 but infection was not blocked by anti-CD4 antibodies. Apparently HIV infection of these cells does not involve CD4 as the cellular receptor.

Antibodies, Viral↗

PubMed1989

Herpes zoster following spinal surgery.

The onset of most cases of herpes zoster is usually sudden and unexpected. A precipitating factor is seldom obvious. Depressed cellular immunity or an underlying neoplasm are found in only a small number of patients. The relationship between trauma and reactivation of the varicella-zoster virus is uncertain and most of the published cases follow trivial external injury.

Herpes Zoster↗

PubMed1989

Pacemaker dermatitis.

Explore the source record for details and available documents.

Dermatitis, Contact↗

PubMed1989

Liver necrosis caused by mushroom poisoning in dogs.

Explore the source record for details and available documents.

Animals↗

PubMed1989

Society of Uroradiology Award paper. The pars infravaginalis gubernaculi: importance in the identification of the undescended testis.

The gubernaculum, a cordlike structure that extends from the testis to the scrotum and guides the testis in its descent, has a bulbous termination, the pars infravaginalis gubernaculi. We reviewed seven surgically proved cases in which the pars infravaginalis gubernaculi was mistaken for an undescended testis on imaging studies. The studies included sonography (five cases), CT (two cases), and MR imaging (two cases). Identification of the mediastinum testis on sonograms or MR images confirms that a structure is testis and not the pars infravaginalis gubernaculi. In two of these patients, testicular venography was used to further identify the undescended testis. In these two patients, the pampiniform plexus, which is used to identify the presence and position of testis, was located adjacent to the pars infravaginalis gubernaculi. Our experience indicates that the pars infravaginalis gubernaculi can be similar in appearance to the undescended testis on any imaging study. The finding of an apparent cord leading to a testislike structure on caudad sectional imaging does not obviate searching for the testis as far as the renal hila.

Adolescent↗