Bisexuality and HIV risk: experiences in Canada and the United States.
Explore the source record for details and available documents.
Bisexuality↗
Biomedical subjects
T Myers
Publications and source records attributed to T Myers.
Understanding the intention of gay and bisexual men to take the HIV antibody test.
This study offers an explanation for the intention of 1,512 gay and bisexual men to be tested for the HIV antibody. Participants were recruited through 125 gay-identified venues (bars, bathhouses, community dances) across Canada. Self-administered questionnaires assessed respondents' intention to take the test in the next year, predictor variables (e.g., attitudes, the perceived social norm of the gay community, perceived behavioral control, and other constructs such as reasons for not being tested and importance of aspects of the test such as confidentiality), and sociodemographic variables. For this analysis, two groups were formed: men who had taken the HIV test in the past with negative or unknown results (Group A) and men who had not taken the test (Group B). The proportions of men who intended to take the test in the next year were 84.8% and 53.3% for groups A and B, respectively. For both groups, logistic regression indicated that the most important factors explaining intention were attitudes toward taking the test and perceived behavioral control. Additional variables specific to each group also contributed to explain intention. Thus, to enhance test-seeking among this population requires a consistent program of health education and facilitative policies.
AIDS Serodiagnosis↗
A novel catecholamine, arbutamine, for a pharmacological cardiac stress agent.
Arbutamine, developed for use as a cardiac stress agent, was compared with isoproterenol and dobutamine in anesthetized dogs for cardiovascular actions prior to and after beta-adrenergic blockade with propranolol. The efficacy and safety of arbutamine were also evaluated in a canine model of myocardial ischemia obtained by partially occluding the left anterior descending coronary artery. Comparison of hemodynamic variables in normal dogs showed that arbutamine was approximately equipotent to isoproterenol in increasing heart rate and cardiac contractility, and in decreasing total peripheral vascular resistance and mean arterial blood pressure. Arbutamine was 210 times more potent than dobutamine in increasing cardiac contractility by 70%; however, at this dose dobutamine exhibited a negative chronotropic response. Beta-adrenergic blockade with propranolol shifted the agonist's dose-response curves for heart rate and contractility to the right; however, low doses of dobutamine exhibited a negative chronotropic effect and increased the total peripheral vascular resistance. In dogs subjected to partial left anterior descending coronary artery occlusion, arbutamine produced significant ST-segment deflections, beginning at a dose of 0.1 nmol/kg/min. Impairment of segment shortening, reflecting cardiac wall motion abnormality, was evident at a dose of 0.3 nmol/kg/min. Isoproterenol did not cause significant changes in these parameters. These results show that arbutamine is capable of producing graded increments in cardiac contractility and rate before and after beta-adrenergic blockage in normal dogs. In dogs subjected to coronary artery occlusion, it is capable of provoking myocardial ischemia at dose levels devoid of toxicity.
Animals↗
Sexual risk and HIV-testing behaviour by gay and bisexual men in Canada.
Behavioural epidemiology is an important aspect of HIV research, particularly among marginalized populations where measurement of rates of infection have not been conducted. This Canadian study provides a country-wide analysis of the characteristics and behaviours of gay and bisexual men, and examines the influence of geographic, socio-demographic and lifestyle influences on sexual behaviour and test-seeking. A purposive sample of 4,803 men was recruited through gay-identified venues. In order to provide national representation seven sampling strata were defined. Data were collected by self-completed questionnaire. A three-level hierarchical logistic regression analysis is used to model two behaviours, unprotected anal intercourse and test-seeking. The results showed that, nationally, 22.9% of respondents reported at least one episode of unprotected anal intercourse in the previous 3 months, and 63% had been tested. Characteristics and behaviours of men varied across the country. Geographic differences appear to be less important in explaining unprotected anal intercourse than test-seeking. In conclusion, policy, programmes and social environment appear to exert an important influence on test-seeking, whereas cultural and psychosocial dimensions appear to have a greater influence on sexual behaviour.
AIDS Serodiagnosis↗
Heparinase-guided thrombelastography in an anticoagulated parturient.
We describe the use of heparinase-guided thrombelastography in the assessment of a parturient who had been anticoagulated with heparin for suspected thromboembolic disease. Reversal of the heparin effect in the heparinase-treated sample facilitated administration of protamine and successful subarachnoid analgesia for delivery.
Adult↗
Fracture and migration of a pacemaker atrial lead retention wire found by fluoroscopic screening in an asymptomatic patient.
We present the case of a woman who had an Accufix atrial "J" pacemaker lead implanted in 1990. Subsequently, Telectronics Pacing Systems recalled two models of the atrial leads after problems with fracture and malfunction were reported. One of these models was used in our case. Fifty-two months after implantation, following recommended fluoroscopic screening, our patient was found to have a complete fracture of the "J" retention wire with one fragment protruding from the sheath in the right atrium and another fragment of the wire lodged in the right ventricle. The pacemaker had continued to function normally and there was no clinical evidence to suggest such a potentially disastrous fracture. Our report emphasizes the importance of fluoroscopic screening of all patients with atrial leads involved in the recall.
Aged↗
In utero exposure to ethanol alters mRNA for insulin-like growth factors and insulin-like growth factor-binding proteins in placenta and lung of fetal rats.
Insulin-like growth factors I and II (IGF-I and IGF-II) play a role in regulating fetal growth and development. Their actions in target tissues are modulated in part by binding to IGF binding proteins 1 and 2 (IGFBP-1 and IGFBP-2). In this study, we examined the effect of fetal exposure to alcohol IGF-I and on IGF-II and IGFBP-1 and IGFBP-2 mRNA in placenta and fetal lung tissue. Timed-pregnant Sprague-Dawley dams were fed a diet consisting of 35% ethanol-derived calories [alcohol-fed (AF)], an Isocaloric diet with sucrose substituted for alcohol (pair-fed; PF), or ad libitum rat chow (CF). Alcohol feeding began on gestational age (G) 14. At G20, dams were killed, and we examined placenta and fetal lung for the steady-state levels of mRNA for IGF-1 and IGF-II and for IGFBP-1 and IGFBP-2. In all dams, body weight increased throughout gestation, and there were no differences between the three groups. At G20, the mean weight for the fetuses from the AF group was lower (p < 0.001) than the fetuses from the CF and PF groups. Steady-state mRNA levels were detected in fetal lung and in placentas by Northern-blot hybridization analysis and semiquantitated by slot-blot hybridization analysis. Multiple transcripts for IGF-I and IGF-II, 1.8 kb species for IG-FBP-1 and 1.6 kb species for IGFBP-2 were detected from total RNA isolated from the fetal lung and placenta, Slot-blot hydridization analysis of fetal lung RNA showed that IGF-I mRNA was significantly increased (p < 0.001) in AF males and females by 4.0 +/- 0.28-fold and by 3.25 +/- 0.2-fold, respectively. IGF-II transcript levels were not affected. IGFBP-1 and IGFBP-2 were increased in AF males, whereas only IGFBP-2 was increased in AF females. In the placenta, there was a significant increase in IGFBP-1 and IGFBP-2 transcripts [(p < 0.001) 1.75 +/- 0.5-fold and 3 +/- 0.53-fold increase, respectively]. No differences between the groups in serum levels of IGFBP-1 or -2 were detected when measured by Western-blot analysis. The increased gene expression for IGFBPs within fetal lung and placenta may decrease bioavailability of locally synthesized, IGFs that may contribute to the fetal growth retardation observed in this model system.
Animals↗
The role of policy in community pharmacies' response to injection-drug use: results of a nationwide Canadian survey.
The response rate to this survey reflects the salience of the topic and the professional concern about and interest in issues presented by HIV. The HIV/AIDS epidemic has presented pharmacists with one of the greatest challenges to their professional training, ethics, and practice. It further expedites a current re-examination that is occurring among community pharmacies concerning their roles in community health practices. In response to HIV there have been dramatic and unprecedented changes in pharmacy policy and practices. Clearly, some community pharmacies have led the way and influenced policy and practices. In view of the recent introduction of many of these policies and practices, it is likely that change will continue. Survey respondents were, in general, very comfortable with an expanded role involving counseling, health promotion, and disease prevention, consistent with a broader role for community pharmacies in general that has been recently advocated. Community pharmacies serve all areas of the country, in communities large and small; many are open seven days a week, and some provide extended hours of service. Community pharmacies may provide an important complement to community outreach programs as a source of clean needles and syringes for IDUs in most communities, and as an alternative service in some communities where more elaborate programs are not feasible. Safer needle use, as part of a health-promotion approach, is divergent from conventional practice. While major changes have occurred, it appears that there has been some polarization of attitudes and response. The explanation for this is not simple, and further analysis is required to determine the full impact from several ethical perspectives that include professional, business, and public health viewpoints. We have highlighted the role that policy has in moving toward preventive and harm-reduction approaches. From a policy perspective, we have found that support from the federal government, regulatory bodies, and professional associations may be an important catalyst to pharmacists' participation in programs. Further, it does not appear to be possible to implement such policies without professional development and continuing education, and collaboration with the community. Based on data on knowledge and educational need, we believe that our study population's lowest levels of information were in such areas as the role of methadone in HIV prevention and the availability of needle-exchange programs. As with other health-promotion campaigns, additional skills training may be important. Movement forward with expanded preventive and harm-reduction strategies by pharmacies will require careful planning. It is anticipated that change in this area will be incremental in nature, and that it is necessary to introduce programs and services into community pharmacies gradually. Successful implementation will require extensive community development and collaboration with other health professionals, public health officials, police, groups who represent IDUs, and persons living with HIV/AIDS. Careful monitoring and evaluation of these programs will be necessary to enhance their effectiveness.
Canada↗
Brain dysmorphology in adults with congenital rubella plus schizophrenialike symptoms.
Brain morphology was quantified with magnetic resonance imaging (MRI) in adult patients with congenital rubella who also had schizophrenialike symptoms. MRIs were compared with those of adult early-onset schizophrenic patients without congenital rubella and age-matched healthy control subjects. The rubella patients had significantly smaller intracranial volumes and shorter stature than the schizophrenic patients or the controls; however, both patient groups had smaller cortical gray matter, but not white matter, volumes than the control group, even when the MRI volumes were corrected for head size and age. In addition, both patient groups showed significant enlargement of the lateral ventricles but not cortical sulci when compared with expected values of normal adults of the same age and head size. Overall, the pattern of dysmorphology was identical in the rubella and the schizophrenic groups. The observations in the rubella group are consistent with a developmental lesion that limits full brain growth, with the small intracranial volume due at least in part to a severe cortical gray matter volume deficit. Thus, the brain dysmorphology of congenital rubella may provide an instance of prenatal viral infection that models the schizophrenic pattern and provides indirect support for a developmental hypothesis of the neuropathogenesis of schizophrenia.
Adult↗
Measles virus nucleocapsid protein can function in Sendai virus defective interfering particle genome synthesis in vitro.
The Sendai virus P and L proteins, the viral RNA polymerase, and the nucleocapsid protein, NP, synthesized in a transient mammalian expression system support the replication of Sendai virus defective interfering particle (DI) genome RNA in vitro. We have shown that the measles virus nucleocapsid protein, N, can substitute for the Sendai NP protein in genome synthesis. The chimeric product nucleocapsids, which contained Sendai RNA encapsidated with measles N protein, were atypical since they were sensitive to micrococcal nuclease digestion, unlike wild-type Sendai or measles nucleocapsids. The utilization of measles N protein required the endogenous Sendai virus RNA polymerase, since DI nucleocapsids free of polymerase were not replicated. Although both Sendai virus NP and P proteins and measles N and P proteins formed complexes when they were coexpressed, sedimentation analysis showed that measles N protein self-assembled and did not form a complex when expressed with the Sendai P protein. Furthermore, when the Sendai P-L polymerase complex was provided separately, measles N protein alone synthesized DI genome RNA in the absence of Sendai P protein. These data suggest that the self-assembled form of measles N protein functions in Sendai DI genome synthesis.
Capsid↗
Congenital absence of skin and blistering in a neonate. Bart's syndrome and mandibulofacial dysostosis.
Explore the source record for details and available documents.
Abnormalities, Multiple↗
Safety of patent ductus arteriosus closure in premature infants without tube thoracostomy.
During a 30-month period, 34 premature infants underwent surgical closure of a patent ductus arteriosus. The mean gestational age at birth was 25 +/- 0.3 weeks and the mean age at the time of operation was 3 +/- 0.3 weeks (mean weight, 829 +/- 54 g). Indomethacin therapy had failed in 32 patients, and 2 had contraindications to its use. The initial 8 patients had parascapular incision and ligation of the patent ductus arteriosus; the last 26 patients had a short transaxillary incision and clipping. The average duration of the operation from the time of incision to skin closure was 36 +/- 2 minutes (range, 15 to 65 minutes). One patient (3%) needed chest tube insertion intraoperatively because of visceral pleura disruption. Two patients (5.8%) had a "small pneumothorax" (< 10% of the lung field) that resolved within 24 hours. There was no morbidity or mortality directly related to the operative procedure, although 3 patients (8.8%) ultimately died from problems related to their severe prematurity. We conclude that surgical closure of patent ductus arteriosus without chest tube drainage can be accomplished safely in premature infants. Postoperative nursing care is simplified and the cost is reduced because the need for the chest tube and drainage system is eliminated and the number of chest radiograms needed postoperatively is reduced.
Blood Loss, Surgical↗
A comparison of the determinants of safe injecting and condom use among injecting drug users.
A sample of 582 injecting drug users were interviewed as part of an evaluation of an AIDS prevention programme for drug users. This paper examines the biographic and predispositional determinants of five HIV preventive behaviours--equipment sharing (not receiving and not giving) and and condom use (with regular partners, casual partners and sex clients). A two-stage sequential approach was adopted for a logistic regression analysis. Initially, to model each of the five preventive behaviours, biographical and drug use variables were entered. In a second set of models, behavioural predisposition factors were included. Age, drug use and prison experience correlate with variables in both models, although not consistently in the same direction. While a predisposition to reject sharing correlates with safer rejecting and condom use, the predisposition to safer sex only correlates with condom use. Needle exchange programmes that only target the individual would seem to be inadequate. To enhance targeted interventions changes in public and agency policy that create a social environment conductive to behaviour change are required.
Acquired Immunodeficiency Syndrome↗
Dose response effects of hypertonic saline and dextran on cardiovascular responses and plasma volume expansion in sheep.
Despite the established efficacy of 7.5% NaCl/6% dextran-70 in the treatment of hypovolemia, the optimal formulation of a hyperosmotic/hyperoncotic small volume resuscitation solution has yet to be defined. The present study investigates the cardiovascular effects of hypertonic saline ranging from 3.75%-25% NaCl (HS) and dextran-70 (D-70) ranging from 3 to 24%. HS and D-70 were studied alone or in specific combinations at a dose of 4 mL/kg, in euvolemic sheep. Blood samples were collected before, during and up to 60 min after infusion of the test solutions. Dose-dependent effects of HS were immediate increases in cardiac output (CO) of 30-85%, falling to 10-35% over baseline after 60 min. HS concentrations over 3.75% significantly reduced systemic vascular resistance, but HS had no significant effect on mean arterial pressure (MAP). Plasma volume (PV) expansion with HS was an immediate, but transient increase of 12-35%. Infusion of D-70 induced sustained 10-20% increases in CO and 10-30% increases in PV, peaking 10 min post-infusion. D-70 also resulted in small (5-12 mmHg) increases in MAP. Cardiovascular effects of D-70 correlated with a dose-dependent increase in plasma dextran concentrations. All HS solutions significantly increased plasma Na, which peaked at > or = 200 mEq/L in the 25% group. The effects of D-70 and HS combined were additive on PV expansion and CO. These data indicate that concentrations of HS and D-70 which are higher than those currently used have a greater capability for expanding PV, but use of HS > 7.5% may be limited by resulting hypernatremia.
Animals↗
Reducing volunteer bias: using left-over specimens to estimate rates of HIV infection among inmates in Ontario, Canada.
OBJECTIVE: To estimate the prevalence of HIV-1 infection among adult and young offenders admitted to remand facilities in the province of Ontario, Canada, by using a design that reduces volunteer bias. METHODS: A study using a modified anonymous HIV-surveillance design was conducted with urine specimens routinely collected from male and female entrants to all Ontario jails, detention and youth centres between February and August 1993. Information on sex, age, and history of injecting drug use was also collected. Urine was screened using a modified commercial HIV enzyme-linked immunosorbent assay kit and confirmed using a modified in-house Western blot assay. RESULTS: Data were obtained on 10,530 adult men, 1518 adult women, 1480 young male offenders, and 92 young female offenders. Urine specimens were available for 88% of new entrants. Of the entrants, 1% (n = 163) refused to have their urine used for research. Refusals were not associated with history of injecting drug use. Overall rates of HIV-1 infection were 1% for adult men, 1.2% for adult women, and 0% for young offenders. Both the rates of infection and prevalence of injecting drug use varied across facilities and geographic regions. Overall, 13% of adult men, 20% of adult women, 3% of young male offenders, and 2% of young female offenders reported a history of injecting drug use. Rates of infection were highest among self-reported injecting drug users. Rates of HIV were 3.6% for adult men and 4.2% for adult women who injected compared with 0.6 and 0.5%, respectively, for non-injecting drug users. CONCLUSIONS: The use of unlinked left-over specimens is an important tool for measuring HIV-prevalence rates and should be encouraged. The results indicate that HIV rates are much higher among those entering prisons than in the general population. The pattern of HIV in Ontario prisons is similar to that reported in Europe and the United States. We are optimistic that these data will stimulate much needed efforts towards education and health promotion, and open the door to further research in Canadian prisons.
Acquired Immunodeficiency Syndrome↗
Back pain that threatens livelihood.
Explore the source record for details and available documents.
Back Pain↗
Lens-induced glaucoma 65 years after congenital cataract surgery.
PURPOSE/METHODS: We observed an unusual case of lens-induced glaucoma that occurred 65 years after congenital cataract extraction. We successfully treated the patient by removing the residual lens material with pars plana vitrectomy. RESULTS/CONCLUSIONS: The intraocular specimen exhibited lens material, epithelial cells, and macrophages. It may have taken years for the residual lens material to denature and break into small pieces, which resulted in phacolytic and lens-particle glaucoma.
Aged↗
Predictive statistics and artificial intelligence in the U.S. National Cancer Institute's Drug Discovery Program for Cancer and AIDS.
The National Cancer Institute's drug discovery program screens more than 20,000 chemical compounds and natural products a year for activity against a panel of 60 tumor cell lines in vitro. The result is an information-rich database of patterns that form the basis for what we term an "information-intensive" approach to the process of drug discovery. The first step was a demonstration, both by statistical methods (including the program COMPARE) and by neural networks, that patterns of activity in the screen can be used to predict a compound's mechanism of action. Given this finding, the overall plan has been to develop three large matrices of information: the first (designated A) gives the pattern of activity for each compound tested against each cell line in the screen; the second (S) encodes any of a number of types of 2-D or 3-D structural motifs for each compound; the third (T) indicates each cell's expression of molecular targets (e.g., from 2-dimensional protein gel electrophoresis). Construction and updating of these matrices is an ongoing process. The matrices can be concatenated in various ways to test a variety of specific hypotheses about compounds screened, as well as to "prioritize" candidate compounds for testing. To aid in these efforts, we have developed the DISCOVERY program package, which integrates the matrix data for visual pattern recognition. The "information-intensive" approach summarized here in some senses serves to bridge the perceived gap between screening and structure-based drug design.
Antineoplastic Agents↗