Prevalence of high-risk sex among HIV-positive gay and bisexual men: a longitudinal analysis

INTRODUCTION: This longitudinal study examined the prevalence and demographic correlates of unprotected insertive and receptive anal intercourse among HIV-positive gay and bisexual men who were aware of their serostatus. METHODS: Participants (n = 395), sampled randomly at two HIV outpatient clinics in Los Angeles, completed two waves of self-administered questionnaires (separated by approximately 7-9 months) that measured sexual behaviors in the previous 60 days. RESULTS: The cross-sectional prevalence of unprotected insertive anal intercourse was 11.2% at time 1 and 7.1% at time 2. Longitudinal analysis indicated that nearly 15% of the participants had engaged in that high-risk behavior either at time 1 or time 2 and approximately 4% had engaged in the behavior at each time period. Similar rates of unprotected receptive anal intercourse were observed. These high-risk activities were more prevalent with seropositive and unknown serostatus partners than with seronegative partners. The rate of anal intercourse risk behaviors was higher among asymptomatic men and among those who were exclusively gay. CONCLUSION: The findings demonstrate considerable differences in the prevalence of stable and occasional high-risk sexual behaviors among HIV-positive gay and bisexual men. Simple cross-sectional analyses cannot capture the stability or variation in behavior across time and, thus, may generate misleading conclusions about disease transmission, especially if the partner's HIV serostatus is not considered in the analysis. The findings indicate a need for focused safer-sex interventions for seropositive men. The HIV outpatient clinic is an ideal setting for such interventions.     

Autoradiographic distribution and physiological regulation of 2-[125I]iodomelatonin binding in rat epididymis

Autoradiographic study was conducted to localize 2-[125I]iodomelatonin binding in the rat epididymis. In the peripubertal (6 weeks old), postpubertal (8 weeks old) and adult (3 months old) rats, intense specific 2-[125I]iodomelatonin labelling of the corpus epididymidis was observed. The intensity of 2-[125I]iodomelatonin binding in the distal epididymal segment was significantly decreased in orchidectomized rats but the effect could be reversed with testosterone replacement. The intensity of 2-[125I]iodomelatonin binding in the distal rat epididymal segment did not show any diurnal rhythmicity when mid-light period and mid-dark period levels were compared, and was unaffected by constant lighting. Our data suggest androgen-dependent expression of 2-[125I]iodomelatonin binding sites, independent of light-induced changes in circulating melatonin, in the rat corpus epididymidis. A novel role of melatonin and its receptor in the regulation of the functions of rat corpus epididymidis is strongly implicated.     

Determination of antibody specificity to a new influenza B virus variant by means of the immunoadsorption test

Immunoadsorption test was used for determination of the strainspecificity of antibody to a new antigenic variant of influenza B virus (B/Hong Kong/5/72 and B/Yamagata/1/73) in human sera collected in April, 1973--March, 1974. The new strains were shown to be circulating in Moscow City only late in February and in March 1974. The experimental data show the immunoadsorption test to give more definite ideas not only on the qualitative differences between strains but also on the specificity of the immunologic response.     

Cell population mechanisms of inhibition of erythropoiesis in polycythemia

The ciliary activity of Ctenophore bolinopsis is inhibited by decreasing concentration of Mg2+ and increasing concentration of Ca2+ in the medium. The same changes in Mg2+ and Ca2+ concentration trigger muscle contractions and bioluminescence. Co2+ arrests the cilia beating in the rectangular position. An increase in Mg2+ concentration or decrease in Ca2+ concentration switch off the nervous inhibitory mechanisms of ciliary activity, suppress muscle contractions and bioluminescence. Ni2+ produces a similar effect, but the ciliary heating is only slightly accelerated, by the contrast to the effect of increased Mg2+ concentration. A Cl-free medium Mn2+ and tetrodotoxin in commonly used concentrations are of no effect on the systems studied. Experiments involving changes in K+ concentrations and administration of tetraethylammonium suggest that the resting potential in the examined cells may be due to K+ as the most permeant ion, and that K+-channels in the cell membrane may be voltage--controlled. The proposal about "biionic" (Ca2+/Mg2+) bioelectric control of a number of intracellular reactions is discussed.     

Epithelial and surfactant changes in influenzal pulmonary lesions

Pulmonary epithelial cell destruction in mice infected with PR8-A influenza virus has been studied with light and electron microscopy and enzyme histochemistry, and correlated with pulmonary surfactant activity. All epithelial cell types were infected by the virus, resulting in destruction, pneumonitis, and atelectasis by seven to ten days. Pulmonary surfactant activity decreased progressively following onset of infection, and was minimal by seven to ten days. Before types 1 and 2 alveolar pneumocytes regenerated, the regenerating bronchial cells grew peripherally into some of the denuded alveolar ducts and alveoli to form epithelial nodules. Eventually the types 1 and 2 pneumocytes regenerated to cover the alveolar surfaces that were not invaded by bronchial epithelium. This regeneration was associated with increased surfactant activity in the postinfluenzal lesions, suggesting that the type 2 pneumocytes are a source of surfactant.     

Aspirin-induced hepatic dysfunction in a patient with adult rheumatoid arthritis

A patient with classical rheumatoid arthritis receiving high doses of aspirin developed significant elevation of serum glutamic oxaloacetic transaminase. This patient had recently been on phenylbutazone and an initial liver biopsy, at the time of elevation of the transaminase revealed nonspecific mild fatty infiltration of the liver compatible with the pathology seen with rheumatoid disease. Because of the severity and activity of her rheumatoid arthritis, and thus the need to know whether aspirin was the etiologic factor in liver dysfunction, the patient was challenged with aspirin. SGOT elevation occurred after a 4-6 day lag period, which promptly remitted when salicylates were discontinued. A liver biopsy at this time revealed evidence for degeneration, regeneration, and mild focal mononuclear infiltration. Although previous reports note salicylate-related hepatocellular dysfunction in patients with systemic lupus erythematosus and juvenile rheumatoid arthritis, these data clearly demonstrate the relationship of ASA to liver dysfunction in a patient with adult onset rheumatoid arthritis. This histologic picture as well as the clinical course of this patient's hepatic abnormality suggest a toxic rather than hypersensitivity etiology for this syndrome.     

Hemodynamic study in children under 1 year of age

A practical procedure for hypophysectomy of the mouse by paraphyaryngeal approach has been developed by modifying the technics of Motizuki [5] and Lostroh and Jordan [4]. Postoperative care in C3H/He strain of female mice was also studied. The main points improved are as follows: (a) The dental drill bar made of a needle with 2mm outer diameter was devised for making a hole in the cranium (Fig. 2). The bar does not grind the cranium, but cuts it in the circle, resulting in speeding up of the operation and in little bleeding, since the hole is very small. (b) Special attention was paid in breathing of mice during the operation. A longitudinal midline incision of about 1cm was made in muscle encircled the trachea and a pinhole was made by sewing needle into the trachea. A small piece of cotton wool was put on the pinhole and covered by the muscle. It admirably keeps the tracheal hole open for breathing during operation (Fig. 1). (c) After the operation, the mouse was placed in a chamber filled with an atmosphere of 95% O2-5%CO2 gas until recovered, otherwise, all mice died in a few days after operation with inflamation of the lung. The temperature of the recovery chamber is recommended to be kept at about 28 degrees C for ensuring the resuscitation. The intraperitoneal injections of hydrocortone-acetate (0.25mg/0.1ml) just before and 2 days after operation further ameriolated the survival rate.     

Histopathologic spectrum of benign proliferative and intraepithelial neoplastic reactions of the uterine cervix

A working model for the histogenesis of carcinoma of the uterine cervix is summarized in Table I. The inclusion of squamous metaplasia in this chart does not imply that this reaction falls into the spectrum of cervical neoplasia or is necessarily an antecedent to neoplasia. It does simply imply that the carcinogenic event or events apparently occur in or involve an epithelium that is indistinguishable from squamous metaplasia. The chart intentionally implies that the lesions mentioned are not separate diseases but arbitrary points in the spectrum of cervical neoplasia. It must be emphasized that one stage does not necessarily progress to the next and that at any stage up to indisputable cancer the changes may regress, persist or progress. The careful evaluation of histologic material from the uterine cervix will permit the pathologist to exclude those epithelial abnormalities which are not a part of the spectrum of cervical neoplasia and allow him or her to place the patient with cervical neoplasia at the proper stage in the development of the process. With this information the clinician can then intelligently plan appropriate therapy.     

Delinquency, institutionalization, and time orientation

Investigated the temporal orientation of delinquents and nondelinquents while adequately controlling institutionalization. Four groups of 17-25 yr old males ( N = 183) were selected: institutionalized delinquents (prison inmates), institutionalized nondelinquents (soldiers), noninstitutionalized delinquents (delinquents on probation), and noninstitutionalized nondelinquents (vocational students). Findings support most of the hypotheses: Although all Ss were basically future oriented, institutionalized Ss were more present oriented than their noninstitutionalized counterparts. As the prisoner approached release, there was a decrease in the salience of the present and an increase in the salience of the future in his life space. Delinquents (both in and out of prison) perceived the past as more negative and the future as more positive than did nondelinquents. Institutionalized Ss perceived the present as more negative than their noninstitutionalized counterparts. The affective attitudes of the nondelinquents toward the past, present, and future were much more balanced and realistic than that of the delinquents. (57 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)