PURPOSE: The purpose of this study was to compare defect extent and severity and myocardial uptake with exercise and pharmacologic stress with technetium-99m (Tc-99m) tetrofosmin tomographic myocardial perfusion imaging. BACKGROUND: Detection of stress-induced myocardial perfusion defects depends on both a disparity in blood flow between normal and stenotic vessels and the extraction fraction and linearity of myocardial uptake of the tracer. There are limited clinical data for exercise or pharmacologic stress with Tc-99m tetrofosmin tomographic myocardial perfusion imaging. METHODS: Thirty-one patients with coronary artery disease and 7 with a < 5% likelihood of coronary artery disease underwent on separate days Tc-99m tetrofosmin single-photon emission computed tomographic imaging at rest and after exercise, dipyridamole, adenosine, and dobutamine stress. Images were interpreted by a blinded consensus of 3 experienced readers with a 17-segment model and 5-point scoring system. RESULTS: Compared with exercise, the summed stress score was smaller with dipyridamole (P < .01), and the reversibility score was smaller with both dipyridamole (P < .01) and dobutamine (P < .05), whereas the number of abnormal and reversible segments was less with both dipyridamole (P < .01 and P < .001, respectively) and dobutamine (both P < .05). No significant differences were found in the summed stress or reversibility scores and the number of abnormal or reversible segments between exercise and adenosine. CONCLUSIONS: Compared with exercise, defect extent, severity, and reversibility are less with dipyridamole and dobutamine with Tc-99m tetrofosmin single photon emission computed tomographic imaging.

Adenosine↗

PubMedDate not supplied

Influence of arm positioning on rest/stress technetium-99m labeled sestamibi tomographic myocardial perfusion imaging.

BACKGROUND: Single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) is routinely performed with patients' arms positioned above their heads to avoid potential attenuation artifact and reduced image quality. Currently no data are available to support the use of this practice using 99mTc SPECT MPI: METHODS AND RESULTS: Forty-one patients referred for routine rest/stress MPI were imaged using the standard protocol with arms positioned above their heads and again with their arms at their sides. The patients were injected with 10 to 45 mCi (370 to 1665 MBq) of 99mTc-labeled sestamibi (99mTc-sestamibi), and SPECT images were acquired 30 to 90 minutes later. Thirty patients were imaged on an ADAC Vertex dual-head camera and 11 patients on an ADAC Cirrus single-head camera. Images were interpreted by 3 nuclear cardiologists without knowledge of patient identity, arm position, or camera type using a 17-segment scoring model. No significant differences were noted in the percentage of abnormal study results, reversibility extent, or location of MPI defects between the 2 arm positions in the same patients. Image quality was also similar. CONCLUSION: Arm positioning does not influence the interpretation of 99mTc-sestamibi SPECT myocardial perfusion imaging with regard to image quality or defect location and extent.

Adult↗

PubMedDate not supplied

Apolipoprotein E genotype, vascular risk and early cognitive impairment in an African Caribbean population.

A reduced risk of Alzheimer's disease (AD) associated with the apolipoprotein E (APOE) epsilon4 allele is reported in populations of African origin. In order to clarify possible reasons for this, we examined the association between APOE genotype and early cognitive impairment in a community-based African Caribbean UK population aged 55-75 years. APOE genotype was available for 202 participants, 57 (28%) of whom were classified as having relative cognitive impairment on a battery of neuropsychological tests. Cognitive impairment was negatively associated with epsilon2 and positively but more weakly associated with epsilon4. Effects of both alleles increased markedly after age 70. The effect of epsilon4 was increased in combination with hypertension, diabetes or lower educational attainment, but these factors did not influence epsilon2 effects. Cholesterol and triglyceride levels partially explained effects of epsilon2, but did not account for those of epsilon4. A reduced association between epsilon4 and later AD in populations of African origin is unlikely to be explained by reduced cognitive effects or by differential mortality. However, it may be accounted for by vascular comorbidity. The different patterns of association between epsilon2 and epsilon4 alleles suggest different pathways of effect.

Black or African American↗

PubMedDate not supplied

The Gospel Oak project 1987-1990: provision and use of community services.

This longitudinal survey of elderly people examines morbidity and service usage. 705 elderly people who lived in their own homes were interviewed as part of the Gospel Oak project in 1987/88, and in 1990, 524 (74.3%) were re-interviewed--90 (12.8%) had died, 51 (7.2%) had moved and 40 (5.7%) refused a follow-up interview. The results indicate that 60% of residents (1987/88 and 1990) had been in contact with community services within the month before the survey. Respondents with depression were mostly in contact with the health service, those with dementia were in contact with social services. Long-term activity-limited people had high contact with both services, although this finding was less likely among newly activity-limited people. Multiple service-users from the first survey were likely to be either dead, or high service-users in 1990. Low service-users tended to continue to be low service-users. New users were generally living alone, aged around 70 years and had been relatively healthy previously. Respondents who stopped using services were generally younger, mostly women, and possibly depressed. People who had never been service-users, were generally younger and healthier. Information on community services performance is inadequate to ensure targeted, efficient services, and this survey gives detailed information to help planning and resource allocation.

Aged↗

PubMedDate not supplied

Effect of human gamma interferon on mice testis: a quantitative analysis of the spermatogenic cells.

Effect of Human Gamma Interferon (Hu-IFN-gamma) on the testicular histology was studied in mice. Male mice were administered Hu-IFN-gamma intratesticularly at the doses of 2, 10 and 20 micrograms/testis in a volume of 1.0 microliter isotonic normal saline. Contralateral testis served as control and was administered same amount of vehicle. All the animals were sacrificed 7 days after drug administration. Body weight and the weights of testis and epididymis were not affected by IFN treatment nor was there any effect of the drug on the motility of the vas deferens spermatozoa. Low dose of IFN (2 micrograms) did not have significant effect on the histoarchitecture of the testis and various spermatogenic elements, a progressive damage was however observed with the increasing doses of IFN. Pronounced deleterious effect of IFN on the testis leading to desquamation of the germinal epithelium, reduction in the germinal cell height and tubular diameter was observed with 20 micrograms dose. Quantitative studies on seminiferous epithelium showed a significant decrease in the number of Sertoli cells, stage-7 spermatids and stage-16 spermatozoa. The ratios of resting type spermatocyte: type A spermatogonia and stage-7 spermatids: pachytene spermatocyte was also reduced. The ratios of pachytene spermatocyte: resting spermatocyte and stage-16 spermatozoa: stage-7 spermatids were however not affected by IFN treatment. In another experiment IFN was administered (2 micrograms/day) subcutaneously to male mice for 30 days. No effect of drug treatment on body weight, organ weight, sperm motility and histology (including morphometry) of the testis was observed. Our data suggest that IFN action at testis may be associated with the antiproliferative effect of interferon.

Animals↗

PubMedDate not supplied

Psychiatric aspects of AIDS. New directions for research.

Explore the source record for details and available documents.

Acquired Immunodeficiency Syndrome↗

PubMedDate not supplied

Effect on human gamma interferon on mice testis: a quantitative analysis of the spermatogenic cells.

Effect of Human Gamma Interferon (Hu-IFN-gamma) on the testicular histology was studied in mice. Male mice were administered Hu-IFN-gamma intratesticularly at the doses of 2, 10 and 20 micrograms/testis in a volume of 1.0 microliter isotonic normal saline. Contralateral testis served as control and was administered same amount of vehicle. All the animals were sacrificed 7 days after drug administration. Body weight and the weights of testis and epididymis were not affected by IFN treatment nor was there any effect of the drug on the motility of the vas deferens spermatozoa. Low dose of IFN (3 mukg) did not have significant effect on the histoarchitecture of the testes and various spermatogenic elements, a progressive damage was however observed with the increasing doses of IFN. Pronounced deleterious effect of IFN on the testis leading to desquamation of the germinal epithelium, reduction in the germinal cell height and tubular diameter was observed with 20 micrograms dose. Quantitative studies on seminiferous epithelium showed a significant decrease in the number of Sertoli cells, stage-7 spermatids and stage-16 spermatozoa. The ratios of resting type spermatocyte: type A spermatogonia and stage-7 spermatids: pachytene spermatocyte was also reduced. The ratios of pachytene spermatocyte: resting spermatocyte and stage-16 spermatozoa: stage-7 spermatids were however not affected by IFN treatment. In another experiment IFN was administered (2 micrograms/day) subcutaneously to male mice for 30 days. No effect of drug treatment on body weight, organ weight, sperm motility and histology (including morphometry) of the testis was observed. Our data suggest that IFN action at testis may be associated with the antiproliferative effect of interferon.

Animals↗