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Biomedical subjects

R H Moore

Publications and source records attributed to R H Moore.

At least 73 records · Page 4Linked to original sources
PubMed1988

Redistribution of visceral blood volume in upright exercise in healthy volunteers.

Exercise induced changes in the blood volume of visceral organs (cardiopulmonary and liver, spleen, and kidneys) were determined by scintillation camera imaging of the distribution of technetium-99m-labeled red blood cells in the thorax and abdomen of ten healthy adult volunteers. Graded upright bicycle exercise was performed to the point of exhaustion with the volunteer positioned with his/her back to the scintillation camera and data recording was synchronized to the pedal cycle to minimize patient motion artifacts within the data. The first image from each level of exercise was analyzed by placing regions of interest over the spleen, liver, kidneys, and right lung. The counts in each organ were expressed as a percent of activity at zero workload. Analysis of data using Hotelling's t-squared analysis to see if overall differences existed between the last four measurements (up to the time of exhaustion) regarding percent change from baseline for spleen, kidney, liver, and right lung were made. The splanchnic bed had a significant decrease in blood volume. The spleen decreased 39%, while the liver decreased 14%. For the kidney and liver, no significant differences were achieved (p greater than 0.24, p less than 0.15, respectively). The lung increased its blood volume to 128% of control, significant with p less than 0.02. This data demonstrates that in healthy volunteers there is normal redistribution of blood volume during maximal exercise with a significant reduction in blood volume of the spleen as well as a significant rise in blood volume within the lungs.

Adult↗
PubMed1988

The concurrent validity of the MacAndrew Alcoholism Scale among at-risk adolescent females.

This study investigated the empirical validity of the MacAndrew Alcoholism Scale as a measure of alcohol abuse, marijuana use, and related multiple substance use in a sample of N = 160. Classification accuracy was 45% for alcohol abuse, 48.8% for marijuana use, and 66% for related multiple substance use (n = 12). There were few differences in personality functioning as measured by the California Psychological Inventory between true positives and false negatives. Both groups exhibited adolescent qualities, i.e., irresponsibility, attraction to pleasure seeking, and minor rebelliousness. False negatives appeared to be slightly less impulsive and somewhat less secure about themselves. Both groups were also similar in terms of reported use of alcohol. They used alcohol to enhance a sense of well-being, i.e., to gain pleasure and to reduce dysphoric affect, but not to reduce inhibitions in social relationships. However, true positives tended to use alcohol to help cope with problems in personal relationships, such as rejection. Some limitations of the study, especially in relation to recent formulations of female alcoholism by MacAndrew (1986), were discussed.

Adolescent↗
PubMed1988

Observations on the role of endotoxin in graft-versus-host disease.

We have used a conventional murine model of bone marrow transplantation (BMT) to make a detailed study of the histological features of graft-versus-host disease (GvHD), and to study the effects of oral antibiotic decontamination of the gut flora. Comparison of the histological appearances of the small and large bowel indicated that the features of the GvHD were more severe in the large bowel. Bowel sterilisation caused a striking reduction in the severity of GvHD, both in the gut and at a distant site (the skin of the ear). The different effects of GvHD in the large as compared to the small bowel suggested that a factor was operative locally, and the effect of sterilisation linked this to the bacteria in the bowel. The fact that sites remote from the bowel were also affected suggested that a diffusible factor from the bowel produced by the bacteria of the gut was responsible. Studies elsewhere have suggested that the factor involved is likely to be endotoxin. In these experiments however it was evident that systemic administration of endotoxin did not aggravate the disease process and that in some instances the reverse was obtained. If therefore endotoxin is important the dose and its mode of its administration are likely to be critical.

Animals↗
PubMed1987

Cardiac response to daily activities and exercise in normal subjects assessed by an ambulatory ventricular function monitor.

The cardiac response to a variety of daily activities was assessed in 18 healthy adult subjects (mean age 31 years, range 21 to 39) with an ambulatory ventricular function monitor (VEST), which records serial beat-to-beat radionuclide and electrocardiographic data. The VEST was positioned and calibrated using data recorded during a multigated blood pool scan. It was worn for an average of 3.0 +/- 1.1 hours, while the subjects performed the following activities: sitting quietly (baseline); standing in place; walking; climbing stairs; bicycle or treadmill exercise; eating; sitting in a room at 4 degrees C for 20 minutes; and urinating. To calculate ejection fraction (EF), relative end-diastolic counts, relative cardiac output and heart rate, the beat-to-beat data were averaged over 15 to 30 seconds. Compared with baseline, standing increased EF by 0.03 +/- 0.04 and decreased end-diastolic volume by 10.9 +/- 4.7%. Walking and climbing stairs increased EF by 0.10 +/- 0.05 and 0.18 +/- 0.09, respectively, and increased end-diastolic volume by 7.8 +/- 5.3% and 12.8 +/- 4.3% (p less than 0.001). Eating increased EF by 0.02 +/- 0.03 and decreased end-diastolic volume by 11.3 +/- 6.1% (p less than 0.001). Cold stimuli and urinating decreased EF by 0.05 +/- 0.04 and 0.03 +/- 0.04, respectively (p less than 0.001 and less than 0.05). Serial left ventricular function monitoring during graded bicycle and treadmill exercise revealed a rapid increase in EF in the early stages of exercise, with no further change in the late stages. Heart rate and systolic blood pressure increased progressively with each successive stage.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗
PubMed1987

Antibody titres to a rough-mutant strain of Escherichia coli in patients undergoing allogeneic bone-marrow transplantation. Evidence of a protective effect against graft-versus-host disease.

Much clinical and experimental evidence suggests that infection and graft-versus-host disease (GvHD) are commonly associated as complications of bone-marrow transplantation (BMT). A likely basis for this association is the gram-negative faecal flora,the origin of many septicaemias and a source of bacterial endotoxin, which has potent immunostimulatory effects. A rough-mutant strain, Escherichia coli J5, has only core determinants in its endotoxin,and antibodies to E coli J5 protect animals and human beings from the consequences of septic shock. Naturally occurring antibodies to E coli J5 ("anti-endotoxin") were assayed in serum from patients undergoing BMT, healthy controls, and patients with obstructive jaundice. BMT recipients had significantly lower titres than the other two groups. Furthermore, the titre of IgM class anti-J5 antibody was significantly associated with protection from GvHD.

Acute Disease↗
PubMed1987

Biodistribution of tantalum-178: a short-lived radiopharmaceutical for blood pool imaging.

178Ta is a short lived radionuclide (half life = 9.3 min), which results in favorable radiation exposure compared to 99mTc (half life 6 h). The energy spectrum of 178Ta consists of imageable photons in the 55-65 keV (61.2%) and 93 keV (33.7%) range but also 6% of disintegrations result in photons with energies greater than 500 keV. These high energy photons cause septal penetration in low energy collimators so that resolution is degraded. However, a medium energy collimator prevents the septal penetration of these higher energy photons. Serial blood samples obtained from dog and rabbit models indicate that 178Ta is retained in the blood pool for at least 20-30 min after intravenous injection. The 178Ta appears to be associated with the protein fraction of the plasma and not primarily with the red blood cell fraction as determined by centrifugation and column chromatography. Gated equilibrium blood pool images using 178Ta were comparable in quality to images using the 99mTc labelled red blood cell technique. Therefore, 178Ta may allow comparable equilibrium gated blood pool imaging with much more favorable radiation dosimetry. Thus, serial studies over prolonged periods of observation may be obtained.

Animals↗
PubMed1987

Measurement of both left ventricular function and regional myocardial perfusion with 133Xe in dogs.

A technique to measure left ventricular (LV) function and myocardial perfusion was validated in 12 dogs. 133Xe in saline was injected into the left atrium (LA) or LV and two data sets were obtained using gamma camera imaging: 1) A first pass gated scan for LV function; followed by 2) Sequential images for regional myocardial perfusion. LV ejection fraction and wall motion measurements from the 133Xe blood pool images were compared to ejection fraction (r = 0.88, P less than 0.01) and wall motion (r = 0.83, P less than 0.01) data from 99mTc labeled blood pool scans. The perfusion measurements obtained with the 133Xe method were compared to microsphere data (r = 0.79, P less than 0.01). Measurements after LV 133Xe injection were similar to data following LA injection. Thus, quantitative assessment of global LV function, regional wall motion and myocardial perfusion is possible with LA or LV 133Xe injection and gamma camera imaging.

Animals↗
PubMed1987

Detection of intracavitary masses on gated scans: a phantom study.

A series of 1.5, 2.0 and 3.0 cm diameter paraffin balls were placed on a 3 cm tether within a simulated left ventricular balloon phantom to determine the maximal balloon volume that permitted identification of the lesion. When images were recorded with the phantom stationary, the lesions could be detected at 100, 280 and 360 ml volumes, respectively. When the phantom was set in motion with a fixed 80 ml stroke volume, the lesions were detected at 120, 320 and 360 ml, respectively. These findings suggest that gating does not decrease lesion detection even when the lesion is freely mobile, and a 1.5 cm lesion would be difficult to detect in an enlarged ventricle, but 2 and 3 cm lesions could be detected even in the presence of moderate ventricular enlargement.

Heart↗
PubMed1987

Influence of endotoxin on graft-versus-host disease after bone marrow transplantation across major histocompatibility barriers in mice.

Much clinical and experimental data suggest that infection and graft-versus-host disease (GVHD) are intimately associated, and that bacterial endotoxin (ET), a potent immunostimulant, influences the severity of GVHD. We have used a cell-wall-deficient mutant of Escherichia coli (E coli J5) to study the effect of active and passive immunization against ET in a murine model of GVHD induced by major histocompatibility antigens. CBA/Ca (H-2k) mice were irradiated and grafted with 1 X 10(7) bone marrow cells from C57BL/B6 (H-2b) donors. Groups of mice were immunized against J5: either actively immunized with killed J5 cells or pure J5 lipopolysaccharide, or passively immunized with rabbit anti-J5 antiserum (R alpha J5). Controls included irradiation controls, negative controls (syngeneic graft), positive controls (conventional mice receiving allogeneic graft), mice immunized with normal rabbit serum, Freund's adjuvant (FA), or human serum albumin (HSA) in FA. Active immunization with J5 exacerbated the effects of GVHD as indicated by increased weight loss (P = 0.002) and earlier death (P = 0.043). In contrast, immunization with HSA protected against weight loss (P = 0.028), and improved survival (P = 0.008). Passive immunization with J5 had no effect. These observations support the hypothesis that ET influences the pathogenesis of GVHD, and provide a useful model for studying the effects of ET in a well-defined immunological system.

Animals↗
PubMed1987

Effect of immunization with Escherichia coli J5 on graft-versus-host disease induced by minor histocompatibility antigens in mice.

We have used a cell-wall-deficient mutant of Escherichia coli (E coli J5) to study the effect of active and passive immunization against bacterial endotoxin (ET) in a murine model of acute graft-versus-host disease (GVHD) induced by minor histocompatibility antigens. C57BL/B6 (H-2b) mice were irradiated and grafted with 1 X 10(7) anti-Thy-1.2 and complement-treated bone marrow cells and 5 X 10(7) spleen cells from LP/J (H-2b) donors. Groups of mice were immunized against J5--either actively immunized with killed J5 cells or pure J5 lipopolysaccharide or passively immunized with rabbit anti-J5 antiserum (R alpha J5). Controls included irradiation controls, negative controls (conventional mice grafted with depleted bone marrow only), positive controls (conventional mice grafted with bone marrow and spleen cells), and mice passively immunized with normal rabbit serum (NRS). Positive control mice developed GVHD and all died by day +77. Active immunization partially protected against the rapid weight loss due to GVHD (P less than 0.05) but mice had an earlier onset of GVHD (P less than 0.05) and a shortened survival after onset (P less than 0.05). Median survival time (MST) and overall survival were unchanged. Passive immunization with R alpha J5 delayed death (P less than 0.01), increased MST (P = 0.01), increased overall survival (P less than 0.01), and protected against weight loss (P = 0.01). NRS had no beneficial effect.

Animals↗
PubMed1986

Acute accidental inhalation of U: a 38-year follow-up.

The intake and deposition of U in three men accidentally exposed to soluble natural U compounds in an explosion in 1944 were reevaluated 38 y later by the U.S. Uranium Registry. The initial lung depositions were estimated to be about 40-50 mg of U based on the fragmentary urinary excretion data obtained shortly after the accident. The initial long-term bone deposition was estimated from individual excretion curves and was 410 micrograms (5.2 Bq) in the highest exposed individual, which resulted in an integrated 40-y dose equivalent to the bone surfaces approximately 2 mSv (200 mrem). Medical and health physics examinations of two of the men 38 y after the accident revealed no detectable deposition of U nor any physical findings attributable to U exposure. One of the exposed individuals showed an altered clearance pattern for U shortly after the accident, possibly from pulmonary edema associated with concomitant exposure to acid fumes.

Accidents, Occupational↗
PubMed1986

Idiopathic periodic hypothermia and bizarre behaviour in the presence of occult syringomyelia.

Overt psychological, neurological and haematological abnormalities were present in a 35 year old Jamaican female diagnosed as having idiopathic periodic hypothermia. Although symptoms and signs were ameliorated by warming, no long term satisfactory therapeutic measure was identified. Despite extensive clinical and subsequently histological investigation no cause for the hypothermia was found although she had clinically unsuspected cervical syringomyelia.

Adult↗
PubMed1986

Multigated blood-pool tomography: new method for the assessment of left ventricular function.

A technique for the semiautomatic calculation of left ventricular volumes from multigated blood-pool tomograms (MGBPT) was tested in a series of 12 patients undergoing contrast ventriculography within 48 hr of gated tomography. The parameters necessary for the calculation of volume were developed in a chest phantom study performed with a series of 99mTc-filled balloons representing the right and left ventricles. The images were analyzed for volume using a percentage of peak count-threshold of the left ventricular balloon. This technique resulted in a correlation of r = 0.99 of the calculated to the true phantom volumes (y = 0.87x + 27.4, p less than 0.01, s.e.e. = 7.87 ml). The patient studies were recorded at 16 frames/cardiac cycle at each of 60 angles over a 360 degree rotation. Reconstructed data were presented in an endless loop cine format producing a set of sequential "beating tomographic slices" in the transverse, apical four-chamber, short-axis, and long-axis oblique views. Measurements of end systolic volume (y = 0.79x + 30, r = 0.93, p less than 0.001, s.e.e. = 24 ml), end-diastolic volume (y = 0.63x + 60, r = 0.94, p less than 0.0001, s.e.e. = 20 ml) and ejection fraction (y = 0.88x - 0.02, r = 0.92, p less than 0.001, s.e.e. = 0.08) determined from the semiautomated volume method correlated well with those determined by left ventricular contrast angiography. A qualitative comparison of MGBPT, planar imaging, and left ventricular angiography in 12 patients revealed that the visual assessment of wall motion using the 16-frame tomographic slices had significant advantages over planar and single plane angiographic data in the identification of inferior, basal, and septal wall motion abnormalities as well as the extent of involvement by aneurysm formation. A quantitative comparison of wall motion in the long-axis oblique view of the MGBPT to the RAO 30 degree ventriculogram (y = 0.74x + 8.7, r = 0.82, p less than 0.0001, s.e.e. = 14%) confirmed the qualitative similarity of these two views. We conclude that MGBPT is promising as a method for accurately measuring left ventricular volumes and assessing regional wall motion.

Aged↗
PubMed1985

Construct validity of the MacAndrew Scale: secondary psychopathic and dysthymic-neurotic character orientations among adolescent male misdemeanor offenders.

The empirical validity of the MacAndrew Scale was investigated in 200 adolescent males convicted of misdemeanor offenses who were classified according to their pattern of alcohol intoxication. Classification results were comparable to those from studies of adult men--true positive = 80%, false negative = 20%, true negative = 81% and false positive = 19%. An empirical cluster analysis of factor scores from the California Psychological Inventory yielded 14 personality types. About 56% of these cases resembled two character orientations (Emotional Extraversion or Emotional Introversion) that were hypothesized by MacAndrew to mediate addiction-proneness among males. However, 38.7% of these subjects were not alcohol misusers. The hypothesis that Emotional Introverts tend to be classified as false negatives was not supported--true positive = 79% and false negative = 21%. Although MacAndrew's formulation of two character orientations has heuristic value, the present study found alcohol misuse among adolescents with other personality characteristics. Studies of nonoffender adolescent males were recommended to clarify the MacAndrew Scale's sensitivity to the character orientation Emotional Introvert. Consistent with earlier research, the present study found no evidence of high levels of emotional tension in the form of anxiety or depression among adolescent alcohol misusers.

Adolescent↗
PubMed1985

A World War II uranium hexafluoride inhalation event with pulmonary implications for today.

Two individuals were exposed to massive quantities of airborne uranium hexafluoride (UF6) and its hydrolysis products following a World War II equipment rupture. An excretion pattern for uranium exhibited by these patients is, in light of current knowledge, anomalous. The possible role of pulmonary edema is discussed. Examination of these individuals 38 years later showed no physical changes believed to be related to their uranium exposure and no deposition of uranium could be detected.

Accidents, Occupational↗
PubMed1984

Red cell flexibility and platelet aggregation in patients with chronic obstructive vascular disease (COAD) and study of therapeutic approaches.

The red blood cell flexibility was studied in the blood of twenty patients with severe peripheral vascular disease and twenty matched controls. Patients exhibited significantly less red cell flexibility than controls. In both groups there was an inverse relationship between age and red cell flexibility. No correlation was found between red cell flexibility and sex or smoking history. Pentoxifylline, a xanthine derivative which inhibits phosphodiesterases and platelet aggregation, was found to increase red cell flexibility. This effect of the drug was greater on red cells with imparied flexibility than on normal cells. Various prostaglandins by contrast were found to decrease red cell flexibility, this could be compensated for by pentoxifylline. Forty patients with COAD were treated intravenously with PgE1. Significant inhibition of platelet aggregation and clinical improvement was noticed. It is suggested that combinations of PgE1 and pentoxifylline should be explored in clinical studies.

Adult↗