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Biomedical subjects

C Goodman

Publications and source records attributed to C Goodman.

At least 37 records · Page 2Linked to original sources
PubMed1988

polyhomeotic: a gene required for the embryonic development of axon pathways in the central nervous system of Drosophila.

Hypomorphic alleles of the locus polyhomeotic (ph) produce multiple, homeotic-like transformations in adult flies that mimic dominant mutations in the Antennapedia and Bithorax complexes. Analysis of null alleles of ph has revealed a complex, embryonically lethal phenotype that includes cell death of the ventral epidermis and abnormalities in the patterns of expression of homeotic and segmentation genes. There is also a dramatic alteration in the pattern of axon pathways in the central nervous system, such that the wild-type array of segmentally repeated commissures and connectives is replaced by bundles of axons confined to the hemiganglia of origin. It is possible that this axonal phenotype is the result of loss of neuronal identity caused by abnormal homeotic and segmentation gene expression.

Animals↗
PubMed1987

Hematologic, iron-related, and acute-phase protein responses to sustained strenuous exercise.

This study was undertaken to gain insight into the mechanisms responsible for the hypoferremia occurring after severe exercise. To this end, 18 athletes who were competing in a 160-km triathlon involving canoeing, cycling, and running were evaluated before the race, immediately after the finish, and thereafter at 30 min, 24 h, and 48 h. The evaluation included plasma iron, total iron-binding capacity, lactoferrin, ferritin, haptoglobin, cortisol, various enzymes, and white cell count. The cortisol, white cell count, and lactoferrin were significantly increased immediately after the race, while the plasma iron and transferrin saturation were significantly decreased. There was a 40% but nonsignificant rise in the plasma ferritin at the completion of the race, while the C-reactive protein was raised by nearly 300% at 24 h. In contrast, haptoglobin declined significantly by 24 h but was normal again 24 h later. Quantitative considerations suggested that the lactoferrin was not responsible for removing transferrin iron from circulation and hence causing the hypoferremia. Instead, it seemed more likely that the iron-related changes were occurring as part of an acute phase response initiated by muscle injury.

Acute-Phase Proteins↗
PubMed1987

Labeling in vivo of serotonin uptake sites in rat brain after administration of [3H]cyanoimipramine.

The properties of sites in rat brain labeled in vivo after administration of [3H]cyanoimipramine ([3H]CN-IMI) have been studied. The radioactivity in hypothalamus and cortex 20 min to 2 hr after [3H]CN-IMI administration was reduced in rats pretreated with chlorimipramine (10 mg/kg) 5 min before [3H]CN-IMI. No effect of chlorimipramine pretreatment was seen in the cerebellum; levels of radioactivity in this tissue were subtracted from total levels in hypothalamus and cortex to define specific binding. This represented approximately 50 and 30% of total binding in hypothalamus and cortex, respectively. Specific binding in hypothalamus and cortex was reduced by a number of drugs which are potent blockers of serotonin uptake and the binding was inhibited in a stereoselective manner by the stereoisomers of norzimelidine. In contrast, pretreatment with drugs which are weak inhibitors of serotonin uptake had no effect on specific binding. Experiments using increasing doses of [3H]CN-IMI showed that the binding in vivo was saturable. Lesioning rats with the serotonin neurotoxin 5,7-dihydroxytryptamine resulted in an 80% decrease in the specific binding in hypothalamus and a 35% decrease in cortex. The potencies of drugs to inhibit the specific binding of [3H]CN-IMI in vivo were highly correlated with their previously published potencies for inhibiting serotonin uptake in human blood platelets in vitro and for preventing the serotonin depletion induced by 4-methyl-alpha-ethyl-metatyramine in vivo. These results indicate that [3H]CN-IMI can be given to rats to provide a measure of serotonin uptake sites in the central nervous system in vivo.

5,7-Dihydroxytryptamine↗
PubMed1986

The response of runners to arduous triathlon competition.

As very few of the competitors in a triathlon are truly specialist in more than one of the three disciplines, high levels of physical (and mental) stress may result during the course of the event. We investigated some of the physiological responses occurring in runners participating in an "Iron Man" triathlon consisting of canoeing (20 km), cycling (90 km) and running (42 km), in that sequence. Twenty-one male entrants volunteered as subjects for the study. Prior to the competition, maximal oxygen consumption (VO2max) was determined. Basal venous blood samples were collected on the day prior to the competition and post-exercise venous blood samples were collected within 5 minutes of completion of the race. Serum iron was significantly reduced from a mean basal value of 20.6 mumol X l-1 to a mean value of 8.4 mumol X l-1 after the race. Cortisol levels showed a 3 fold increase after the race. Gross VO2max (l X min-1) and mass standardised VO2max (ml X min-1 X kg-1) were both negatively correlated to cortisol levels after the race (p less than 0.05). Total performance time was not related to gross VO2max (l X min-1) but was well correlated to mass corrected VO2max (ml X min-1 X kg-1). The marked fall in serum iron may have been related to heavy sweating or prelatent iron deficiency. Chronic iron deficiency (without frank anaemia) can impair physical performance, although we were unable to show any significant correlation between serum iron level after the race and time taken to complete the event.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1986

Research on the informal carer: a selected literature review.

This paper gives a selected review of the available research on the role of the family in caring for elderly or handicapped relatives in the community. In particular, studies which describe who the carers are, the nature of their responsibilities and the physical and emotional costs of caring are examined. The implications of the findings from these studies and the recommendations made for improved care are discussed. A need for further research in this area is identified, particularly from a nursing perspective.

Aged↗
PubMed1985

Comparison of the antihypertensive effect of enalapril and propranolol in black South Africans.

Angiotensin-converting enzyme (ACE) inhibitors are useful antihypertensive agents. Enalapril maleate is a new ACE inhibitor with actions similar to those of captopril but with fewer side-effects. A study was conducted on 19 black South Africans with mild or moderate essential hypertension; enalapril was compared with propranolol as monotherapy or together with hydrochlorothiazide in a 1-year randomized, double-blind, parallel study. Neither enalapril nor propranolol alone produced consistent, significant reductions in blood pressure. There were no significant differences between the blood pressure responses to enalapril and to propranolol (either with or without hydrochlorothiazide). It is concluded that neither enalapril nor propranolol is effective as monotherapy in the treatment of hypertension in South African blacks, but that both require the addition of a thiazide diuretic.

Adult↗
PubMed1985

The effect of water intake on body temperature during rugby matches.

The effect of drinking up to 1 litre of fluid on water deficit, sweat loss and rectal temperature was determined during three separate rugby matches played in thermoneutral environments. Each player was allotted a litre of fluid and encouraged to drink 500 ml before the start of the game and a further 500 ml at half-time. The players were weighed and rectal temperatures determined before and after the matches. Rectal temperatures were markedly elevated after all three matches and reached levels which may have been high enough to have impaired performance towards the end of the game. The volume of fluid ingested by the players had no influence on final rectal temperatures. The majority of the players had sweat rate/rectal temperature relationships similar to those of heat-acclimatized subjects. It is concluded that, in a thermoneutral environment, the ingestion of volumes of fluid up to 1 litre has no significant beneficial effect on thermoregulation during rugby games, and that the role of the clothing worn may have a greater influence on thermoregulation than was hitherto envisaged.

Adult↗
PubMed1985

Biochemical responses during recovery from maximal and submaximal swimming exercise.

We set out to demonstrate whether changes in plasma volume, haematocrit and some important blood constituents occurred after swimming 100 m and 800 m, as well as monitoring the duration of these changes. We measured exercise-induced changes in concentration of plasma constituents in eight subjects, and determined the expected effects of haemoconcentration on these constituents. We also investigated the different biochemical responses occurring after maximal exercise (100 m), as compared to submaximal exercise (800 m). The haematocrit increased significantly after the 100 m swim and to a lesser extent after the 800-m swim, returning to basal levels within 30 min. The plasma volume decreased by 16% on completion of the 100 m and by 8% on completion of the 800 m. The blood lactate concentration increased 15-fold and 10-fold after the 100-m and 800-m swims respectively. The plasma potassium concentration increased significantly immediately on completion of the 100-m swim, then decreased significantly at 2 1/2 and 5 min post-exercise, returning to near-basal values at 30 min. The potassium concentration measured after the 800-m event did not differ significantly from basal levels, however the measured concentrations were significantly lower than the concentrations expected on the basis of haemoconcentration. The plasma sodium concentrations measured after both 100-m and 800-m swims were significantly increased. However, calculations correcting for haemoconcentration showed significant losses in total circulating sodium.

Adult↗
PubMed1985

Small intestine transit time and lactose absorption during phototherapy.

Diarrhea is often seen during phototherapy in jaundiced infants. Lactose malabsorption and reduced gut transit time (GTT) are some of the proposed explanations. However, the etiology of the diarrhea is still controversial. We investigated GTT and lactose absorption during phototherapy using the H2 breath test. Breath H2 was measured every 10 min for 150 min after feeding of jaundiced infants with and without phototherapy, and in controls. There were 12 newborns in each group. The time of increase of H2 excretion over 10 ppm was taken as the transit time. Lactose malabsorption was estimated by integrating the area under the excess H2 curve. No difference was found in GTT, lactose absorption, peak breath H2 and the time of the peak between phototherapy-treated infants and jaundiced and nonjaundiced infants. The results did not support the presence of lactose malabsorption during phototherapy and the decreased total GTT reported in the literature was not due to shortened small intestinal transit time.

Breath Tests↗
PubMed1984

Effect of antihypertensive therapy on left ventricular function and myocardial perfusion at rest and during exercise.

We studied left ventricular function by equilibrium-gated technetium-99m ejection fraction and global left ventricular perfusion by thallium-201 scintigraphy in 43 patients with mild to moderate hypertension. Patients were studied at rest and during submaximal (approximately 50% of VO2 max) supine bicycle exercise, off therapy and on four forms of therapy for 16 weeks: methyldopa (n = 9); propranolol (n = 9); hydrochlorothiazide (n = 9); and enalapril (n = 16). None of the patients had focal myocardial ischaemia or heart failure. There were no differences between methyldopa, propranolol, hydrochlorothiazide and enalapril in blood pressure responses to exercise. However, heart rate at rest (57 +/- 4.6 beats/min) and during exercise (108 +/- 8.0 beats/min) was significantly lower in patients on propranolol than in other groups (70 +/- 3.9 and 117 +/- 5.5 beats/min for methyldopa; 75 +/- 3.3 and 119 +/- 4.9 beats/min for hydrochlorothiazide; 74 +/- 2.8 and 125 +/- 2.6 beats/min for enalapril). In the propranolol-treated group, mean ejection fraction fell from 55% at rest to 49% during exercise. This suggests that cardiac output is likely to be lower and peripheral resistance higher during exercise in patients on propranolol than on other forms of treatment. There were no significant differences in coronary perfusion responses to exercise, however, or in the ratio of coronary perfusion to rate-pressure product, between any of the groups. These findings suggest that the limitation in exercise tolerance often reported by patients on beta-blockers is not due to coronary insufficiency during exercise, but to an attenuation of the cardiac output response to exercise, together with a raised peripheral vascular resistance.

Adult↗
PubMed1980

A modified method for the identification of heterozygotes for Gaucher's disease using differential thermal inactivation.

We have found heat inactivation of leukocyte 4-methylumbelliferyl-beta-D-glucosidase to be useful in identifying heterozygotes for adult (chronic) Gaucher's disease. The overlap between high heterozygote values and low normal values is reduced by the heat inactivation step, compared to assays without heating; that is from an overlap of 23% to 6%. Although preliminary, our results indicate that this procedure may be useful in families with adult (chronic) Gaucher's disease.

Chronic Disease↗
PubMed1980

Anaerobic pleural and pulmonary infections.

Radiographic findings are reviewed for 69 patients with bacteriologically proven anaerobic infections in the thorax. On the initial films, the disease was confined to the lung parenchyma in 50%, and to the pleura in 30% of patients. The other 20% had combined pleural and parenchymal disease. Over 50% of cases had lung necrosis on the initial films, and many patients who began with a noncavitary pneumonia developed necrosis during hospitalization despite antimicrobial therapy. Once necrosis developed, resolution was slow with an average closure of 65 days for lung abscesses. Parenthymal disease was usually confined to one anatomic site. This site was almost always in a basal or posterior part of the lungs. Pleural effusions tended to progress very rapidly and always proved to be empyemas. Many empyemas occurred without recognizable pneumonic disease. A few were nosocomial, occurring as a complication of surgery, penetrating chest wounds, or subphrenic abscesses. Many patients developed empyemas as a complication of parenchymal disease, frequently while on antimicrobial therapy. Almost all empyemas required surgical drainage with either a rib resection or decortication.

Adolescent↗
PubMed1976

Constancy and uniqueness in a large population of small interneurons.

The anatomy of 61 of the smallest interneurons in the brain of the locust shows the same tendency toward uniqueness, contancy of neuropil abortizations, and frequency of occurrence of supernumerary cells as does that of 17 large interneurons; the size and number of neurons thus have no obligatory relation to the concept of the unique identifiable neuron.

Animals↗