Nitrate administration increases blood flow in dysfunctional but viable myocardium, leading to improved assessment of myocardial viability: A PET study.

SPECT with 99mTc-labeled agents is better able to detect viability after nitrate administration. Nitrates induce vasodilation and may increase blood flow to severely hypoperfused but viable myocardium, thereby enhancing tracer delivery and improving the detection of viability. Quantitative data on the changes in blood flow are lacking in SPECT but can be provided by PET. The aim of the present study was to use PET to evaluate whether nitrate administration increases blood flow to chronically dysfunctional but viable myocardium. METHODS: 13N-Ammonia PET was used to quantitatively assess blood flow, and 18F-FDG PET was used as the gold standard to detect viable myocardium. Twenty-five patients with chronic ischemic left ventricular dysfunction underwent 13N-ammonia PET at rest and after nitrate administration. RESULTS: A significant increase in nitrate-enhanced blood flow was observed in viable segments (from 0.55 +/- 0.15 to 0.68 +/- 0.24 mL/min/g, P < 0.05). No statistically significant change in blood flow was observed in nonviable segments (0.60 +/- 0.20 vs. 0.55 +/- 0.18 mL/min/g). A ratio of at least 1.1 for nitrate-enhanced flow to resting flow allowed optimal detection of viable myocardium, yielding a sensitivity of 82% with a specificity of 100%. CONCLUSION: 13N-Ammonia PET showed a significant increase in nitrate-enhanced blood flow in viable myocardium, whereas blood flow remained unchanged after nitrate administration in nonviable myocardium. Nitrate use during myocardial perfusion imaging will lead to improved assessment of myocardial viability.     

Penetration and distribution of three lipophilic probes in vitro in human skin focusing on the hair follicle.

Fluorescent model substances of increasing lipophilicity (Oregon Green) 488, Bodipy, FL C5 and Bodipy 564/570 C5) were selected to enable the visualization in the skin using confocal laser scanning microscopy. After measuring the penetration for 18 h, the nonfixed human scalp skin was imaged from the bottom parallel to the stratum corneum and in a cross-section view perpendicular to the skin surface. The images were evaluated by calculating relative accumulation values for different penetrants. The studies indicate that the penetrated amount is highest for Bodipy FL C5 (medium lipophilicity) and lowest for Bodipy 564/570 C5 (high lipophilicity) whereas Bodipy 564/570 C5 (high lipophilicity) reveals the highest relative accumulation in parts of the hair follicle compared to Oregon Green 488 (low lipophilicity). The addition of 30% (v/v) ethanol to the donor phase of substance with a low lipophilicity increases the follicular delivery. From our results we conclude that delivery to the hair follicle can be improved by increasing the drugs lipophilicity and optimizing the composition of the donor phase. However, no conclusion can be drawn about the actual route of transport to the hair follicle.     

A PC-based free text retrieval system for health care providers

The purpose of this paper is to describe the design and development of the Clinical Practice Library of Medicine (CPLM). CPLM is an investigational project aimed at providing health care practitioners with critical in-depth information similar to that obtained from a medical reference library or consultant. When used in conjunction with the physician's knowledge, CPLM can provide valuable diagnostic prompting information to assist in rapidly reaching a suitable diagnosis for timely administration of appropriate treatment. This system may also be used to assist paramedical professionals working in remote areas where other expert medical assistance may not be available.     

PLASMA FOLLISTATIN CONCENTRATIONS INCREASE FOLLOWING LIPOPOLYSACCHARIDE ADMINISTRATION IN SHEEP

1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response.     

Predictors of self-reported problems of confusion among the aged.

Responses to questions on the 1984 Supplement on Aging to the National Health Interview Survey (NHIS) about the experience of personal confusion revealed that two-thirds of those interviewed reported never having an episode of confusion during the preceding year. Of those who reported episodes, fewer than one in five said they were happening with increased frequency. The many meanings of confusion found in the literature prompted a modest local study of what respondents understood by the term when asked the NHIS questions. Of those who admitted occasional confusion, almost two-thirds gave definitions that included memory loss or forgetfulness. Consequently, increased frequency of memory problems and difficulty in remembering were included with other variables in the analyses to identify significant predictors. They emerged the single best predictors of how often a respondent reported getting confused. Others were change in health status, number of functional limitations, educational attainment, and vision problems.     

A preliminary investigation into the long-term injury consequences reported by retired baseball players

Seventy-five retired baseball players participated in a survey (37.8% response rate) in order to establish the long-term consequences of injuries sustained during their playing careers. Respondents had a mean age of 55.8 (+/-11.4) years with a mean age of 41.3 (+/-11.4) years at retirement from play. The mean overall rate of injury suffered per player/playing career was 5.6 (+/-7.1). 54.7% of respondents experienced a major injury (i.e. injury resulting in 5 or more consecutive weeks absence from training and play) with a mean major injury per player/playing career of 1.5 (+/-2.2). The rate for significant injuries (i.e. injury resulting in more than 1 week but less than 5 weeks absence from training and play) was 4.1 (+/-6.5) per player/playing career. Catchers had significantly less injuries than all other positions (p=0.027). 18.7% of all respondents reported suffering from arthritis, 24% from restricted joint mobility and 4% from chronically stiff fingers; all of these conditions were associated with their participation in baseball based on medical examination by their GP or medical specialist. 29.3% of respondents indicated that they had incurred additional medical costs and 12% reported significant loss of income associated with their injuries. Some injuries were severe enough that they resulted in extended stays in hospital producing costs carried by the health care system.