Biomedical subjects

G M Reid

Publications and source records attributed to G M Reid.

36 records · Page 2Linked to original sources

PubMed1995

Children's occupational sex-role stereotyping in 1994.

To update the basis of the explanation of how elementary children evaluate the capability of males versus females to perform occupations which are dominated by males, females, or are gender balanced (neutral) in the workforce 180 girls and 200 boys in Grades 1, 2, and 3 completed a questionnaire indicating which of 39 occupations were mostly done by women, by either, or by men on a 5-point scale. The most and least stereotyped occupations were very like gender-occupational data from 1972 and 1983 and reflected the actual sex-typing in the labor force. Sex and grade differences were noted for male occupations but not for female occupations. Some differences from 1977 data of Garrett, et al. were noted. The neutral status of some occupations appeared to assume a male worker.

Career Choice↗

PubMed1994

Maternal sex-stereotyping of newborns.

Gender as a social category playing a role in the process of how mothers perceive their newborns was investigated. 94 primiparous mothers completed a survey that included a physical and an emotional scale on their newborn infants. Neither scale as a whole discriminated between the male and female newborns; however, a one-way analysis of variance did identify four statistically discriminating items. The four items evidence maternal perceptions that sex-stereotype males as having broad, wide hands, looking tall and large, looking athletic, and being mostly serious--not smiling but not crying. Maternal sex-stereotyped perceptions for daughters would be the inverse of these. 30 items gave similar maternal ratings between the two gender sets. These confirmed prior work in 1974 showing sex-stereotyped physical characteristics outnumber the emotional characteristics. The similarity of current conclusions to the 1974 data suggests less than expected fundamental parental attitudinal change due to increased societal interest and attention to gender and sex-stereotyping.

Adolescent↗

PubMed1993

Sudden infant death syndrome (SIDS): oxygen utilization and energy production.

Reid found selenium (Se) deficient soils were a common factor in two populations with the highest incidence of SIDS world-wide (Indian population of King County Washington State, USA and the population of Canterbury, New Zealand). Reid compared a map of the selenium responsive livestock areas in New Zealand with areas of low soil iodine (I). She found that the 1989 report of areas of the highest SIDS incidence coincided with Se responsive livestock areas combined with low soil iodine. Foster found the 1983-84 incidence of SIDS in USA has the strongest positive correlation with the incidence of goitre in World War I troops (1916). Sodium and strontium were positively related. Emery found a hypernatraemic SIDS victim in a very cold environment. Robertson and Parker associated increased sodium (Na) (used in Scunthorpe, England, as a water softener) with increased incidence of SIDS. Godwin's study of White Muscle Disease in lambs describes Se protection. Skeletal muscle mitochondria from dystrophic animals showed lowered respiratory rates with palmitoyl-dl-carnitine and acetyl-dl-carnitine as substrate. Dystrophic organelles failed to respond to ADP. Rognun found elevated hypoxanthine and an enhanced immune response in most SIDS victims. A syndrome associated with potassium deficiency has been described as a killer of healthy, young Asian men, most often during sleep. This paper describes the interactions of sodium (Na), potassium (K), selenium (Se), and iodine (I) to some factors affecting the utilization of oxygen and the production of energy.

Adenosine Triphosphate↗

PubMed1992

Sudden infant death syndrome (SIDS) and the immune response.

Vitamin E pretreatment significantly prevented E. coli-induced Disseminated Intravascular Coagulation (DIC) in rats (1). DIC, a reduction in fibrinogen and a falling platelet count and diffuse haemorrhage are part of the clinical features of Haemorrhagic Shock Encephalopathy Syndrome (HSES), recognised as a disease entity in the 1980s (2). At the SIDS Conference 1974 Reisinger described the effect of Escherichia coli (E. coli) endotoxin on the rabbit (3). An early effect was a reduction in fibrinogen and a falling platelet count, resulting in the release of relatively large amounts of the neuro-transmitter serotonin, stored in platelets (3, 4). Fibrinogen inhibited the release of serotonin from platelets (24). Serotonin is released from platelets during platelet aggregation (14). Platelet aggregation is inhibited by vitamin E (1). Serotonin is a neuro-transmitter associated with deep sleep, respiratory movements and cardiovascular collapse (3). Death at a later stage involved vascular permeability, edema and haemorrhage. After fibrin-platelet clots had formed DIC was present in lungs, kidneys and other organs (3). Medical researchers in Australia linked almost half of SIDS victims with a poisonous strain of intestinal E. coli bacteria (5). Dietary selenium in the intestinal villous tip is considered a daily modulator of cytochrome P450-dependent metabolism of drugs and toxins absorbed by intestinal mucosa (6). Villous atrophy occurs in HSES (2).

Animals↗

PubMed1991

Sudden infant death syndrome (SIDS) and disordered blood flow.

Naeye (1) has long linked SIDS with low utero-placental blood flow and foetal hypoxia. Gestational hypotension, maternal smoking and disorders of the foetal membranes are considered by Naeye to promote brainstem and neurological abnormalities. Naeye also found that SIDS' victims often showed a growth lag after birth and suggested a reduced oxygen environment after birth which pointed to chronic under-ventilation of the lungs. Another abnormality observed by Naeye was that brown fat was retained for an abnormally long time. Now Mitchell (New Zealand Herald, 27.11.90) has concluded a 3-year study of SIDS' victims in New Zealand and found a combination of stomach sleeping position, mothers' smoking and bottle feeding was implicated in 79% of SIDS' victims. (The sleeping position and maternal smoking may be additive in disordered blood flow). The effect of circulatory shock (cardiogenic) on skeletal muscle mitochondrial activity shows there is a large decrease in the activity of the mitochondrial enzyme cytochrome oxidase during circulatory shock. There is also a reduced capacity to oxidase succinate, pyruvate and palmitoyl carnitine (2). These authors discuss cellular oxidative damage due to severe hypoxia during circulatory shock and the effect on the skeletal muscle mitochondrial electron transport chain (ETC). The reasons for carnitine supplement to these patients are explained. It was concluded that during the course of circulatory shock in humans inactivation or damage to the mitochondrial ETC plays a crucial role in cellular oxidative damage. The activation of brown fat mitochondria via the ETC revolves around elevated blood flow, and the high content of cytochromes which give this tissue its characteristic brownish colour (3]. Other forms of interrupted blood flow, similar to cardiogenic shock disorders in skeletal muscle, will be discussed.

Adipose Tissue, Brown↗

PubMed1991

Sudden infant death syndrome (SIDS): a time lag factor.

A time lag factor of about five days has been identified in an increased incidence of SIDS in relation to a cold day. Sudden exposure to chilling appeared to trigger skeletal muscle weakness and renal failure about five days later in a man found to have only 25% of normal carnitine palmitoyl transferase (CPT) activity in biopsied skeletal muscle. White Muscle Disease is a muscular dystrophy in young ruminants which appears about five days after turnout to pasture in the weaned ruminant raised on a diet deficient in vitamin E and selenium (VESD). Pasture has high levels of linoleic and linolenic acid (high PUFA diet) which are modified by developing rumen bacteria. Corbucci investigated the effects of circulatory shock (cardiogenic) on skeletal muscle mitochondrial activity in humans. Cytochrome oxidase activity fell markedly and, in particular, the capacity to oxidase palmitoyl carnitine was greatly reduced. He considered a consequence of this disorder was sequestration of carnitine as acyl carnitine which could not be recycled. Unusual acyl carnitines have been identified in six out of 13 SIDS victims in a USA group. In Finland, researchers identified a rise in SIDS incidence (mostly found in the prone position) after great and rapid temperature changes. Foster found a relationship between 1984 SIDS incidence and the incidence of goitre in World War I troops.

Animals↗

PubMed1991

A survey of the antibacterial activity of some New Zealand honeys.

To assess the variation in antibacterial activity of honey a survey was carried out on 345 samples of unpasteurized honey obtained from commercial apiarists throughout New Zealand. Most of the honeys were considered to be monofloral, from 26 different floral sources. The honeys were tested against Staphylococcus aureus in an agar well diffusion assay, with reference to phenol as a standard. Antibacterial activity was found to range from the equivalent of less than 2% (w/v) phenol to 58% (w/v) phenol, with a median of 13.6 and a standard deviation of 12.5. Neither the age of the honey samples nor whether they had been processed by the apiarist was associated with lower activity. However, the difference between floral sources in the antibacterial activity was very highly significant. Kanuka (Kunzea ericoides (A. Rich.) J. Thompson. Family: Myrtaceae), manuka (Leptospermum scoparium J. R. et G. Forst. Family: Myrtaceae), ling heather (Calluna vulgaris (L.) Hull. Family: Ericaceae) and kamahi (Weinmannia racemosa Linn. f. Family: Cunoniaceae) were shown to be sources likely to give honey with high antibacterial activity. When antibacterial activity was assayed with catalase added to remove hydrogen peroxide, most of the honeys showed no detectable antibacterial activity. Only manuka and vipers bugloss (Echium vulgare L. Family: Boraginaceae) honeys showed this type of activity in a significant proportion of the samples. The high antibacterial activity of manuka honey was in many cases due entirely to this non-peroxide component.

Anti-Bacterial Agents↗

PubMed1990

Psychophysiological correlates of posttraumatic stress disorder in Vietnam veterans.

We measured event-related brain potential (ERP) component amplitudes and heart rate (HR) to four intensities of randomly presented tones in two matched groups of drug-free male Vietnam veterans: 12 patients diagnosed with posttraumatic stress disorder (PTSD) and 6 normal combat veterans. Subjects were evaluated with structured diagnostic interviews and anxiety and depression rating scales. We found a significant group X intensity interaction for P2 peak amplitude at CZ. Subjects were classified as augmenters or reducers: positive P2 slopes as a function of stimulus intensity implying augmentation and negative slopes implying reduction. Nine of 12 PTSD subjects were reducers (sensitivity of 75%) and 5 of 6 normals were augmenters (specificity of 83.3%). By the third and fourth second following tone onset, the mean HR of PTSD subjects increased more than twice that of the normals. HR change scores were significantly responsive to the manipulation of stimulus intensity and to the difference between our two groups. P2 reduction differentiates Vietnam veterans with combat-related PTSD from combat veteran controls, and PTSD subjects are more autonomically arousable than their combat veteran peers.

Auditory Threshold↗

PubMed1989

Sudden infant death syndrome and lipoproteins.

Lipoprotein secretion and vitamin E transport depend on an adequate supply of inositol which functions synergistically with choline. Feeding rats a choline deficient diet was associated with decreased linoleic and arachidonic acids and increased docosapentenoic and docosahexenoic acids in liver phosphatidylethanolamine. Lipoprotein secretion by the liver is impaired by long chain omega 3 fatty acids and by the high carbohydrate diet of Kwashiorkor. Pulmonary surfactant is a lipoprotein which functions in preventing alveolar collapse in the lung. Inositol supplements to premature infants altered the composition of surfactant phospholipids and reduced the need for oxygen therapy. Oxygen free radicals, generated in oxygen therapy, convert low density lipoproteins (LDL) into potent toxins, without adequate antioxidants and free radical scavengers to block free radical generation. Vitamin E deficiency predisposes humans to increased susceptability to oxygen toxicity leading to Bronchopulmonary dysplasia (BPD), a form of chronic pulmonary insufficiency.

Animals↗

PubMed1989

Effects of repeated drug holidays on serum haloperidol concentrations, psychiatric symptoms, and movement disorders in schizophrenic patients.

In a crossover experiment the authors investigated the effects of repeated weekly, 2-day, haloperidol drug holidays on serum haloperidol concentrations, mental status, and neuroleptic-induced movement disorders in seven chronic schizophrenic patients. Haloperidol concentrations decreased about 64% during the initial 36 hours of drug holiday and subsequently increased slightly during the next 24 hours of drug holiday. Two-day weekly drug holidays for 6 weeks resulted in an average reduction of 25% in serum haloperidol concentrations at all drug holiday points. Mental status and movement disorders scores, rated by observers blind to the drug-holiday condition, were not significantly affected by drug holidays.

Drug Administration Schedule↗

PubMed1988

Papillary collecting tubule synthesis of prostaglandin E2 in Dahl rats.

Isolated kidneys of Dahl salt-sensitive rats (DS) excrete sodium less readily than those of Dahl salt-resistant rats (DR). The collecting tubule is an important source of papillary prostaglandin E2 and is a site of significant sodium reabsorption. We cultured renal papillary collecting tubule cells from 5-week-old, prehypertensive DS and DR on a low salt diet and also after 14 weeks of high salt feeding, and we measured prostaglandin E2 synthetic capacity. Unstimulated renal papillary collecting tubule cells from 5-week-old DS produced 62 +/- 5% less prostaglandin E2 than did comparable cells from DR (p less than 0.001). The cells from DS also synthesized less prostaglandin E2 after stimulation with the calcium ionophore A23187 (67 +/- 6% of control; p less than 0.001) or the addition of exogenous arachidonate (74 +/- 7% of control; p less than 0.01). Urinary prostaglandin E2 excretion was also diminished in the 5-week-old DS compared with their salt-resistant counterparts (18.1 +/- 1.3 vs 23.9 +/- 1.7 ng/24 hr; p less than 0.025). After high salt feeding, the DS became hypertensive but the DR remained normotensive. Renal papillary collecting tubule cells cultured from these DS continued to produce less prostaglandin E2 than those from control rats, both in the basal state (60 +/- 12% of control; p less than 0.09) and after stimulation with ionophore (62 +/- 2% of control; p less than 0.002). In these older animals, the DS continued to underexcrete prostaglandin E2 compared with the DR (29.7 +/- 3.2 vs 42.2 +/- 6.1 ng/24 hr; p less than 0.08). The underproduction of prostaglandin E2 in the papillary collecting tubule of DS may play a role in their inadequate renal natriuretic capacity and contribute to the onset and maintenance of salt-induced hypertension in this strain.

Animals↗

PubMed1987

Sudden infant death syndrome: congenital copper deficiency.

A previous paper describes specific respiratory toxins likely to be associated with Sudden Infant Death Syndrome (SIDS). This paper describes ultrastructural abnormalities in the lung and other tissues in congenital copper deficiency. Congenital copper deficiency is associated with tissue anoxia defects in the development of myelin through a failure of phospholipid synthesis. Phospholipid is part of the membrane structure of cells. The paucity of elastin is attributed to a loss of lysyl oxidase activity. Hypoventilation is considered a feature of SIDS.

Animals↗

PubMed1987

Sudden infant death syndrome. The role of putrefactive toxins in respiratory paralysis and cerebral coma.

The Sudden Infant Death Syndrome (SIDS) is responsible for the death of 10,000 infants annually in the U.S.A. The cause of these deaths is not known; all SIDS infants studied died during sleep in a silent fashion and there are no specific lesions observable post mortem. It may be of significance, however, that nearly half of SIDS infants had a respiratory tract infection in the last two weeks of life while forty percent had bloody froth over their mouths when found, presumably pulmonary oedema fluid. It is hypothesis that improper feeding or diarrhoea may likewise be involved in SIDS and that enterotoxins from putrefactive products are the precipitating event in this syndrome.

Bacterial Toxins↗

PubMed1987

Nitroprusside-induced acute azotemia.

A patient with congestive heart failure and pneumonia was begun on a nitroprusside infusion for cardiac afterload reduction. Urine output declined sharply and azotemia ensued despite little change in arterial pressure. Further evaluation supported a prerenal mechanism with dramatic recovery related to tapering and discontinuation of the nitroprusside. The mechanism of renal deterioration is possibly related to a 'steal' syndrome due to preferential dilation of vascular beds other than the renal.

Acute Kidney Injury↗

PubMed1987

Antigenic diversity in Babesia divergens: preliminary results with three monoclonal antibodies to the rat-adapted strain.

Three murine monoclonal antibodies were raised against the rat-adapted strain of Babesia divergens. In the indirect fluorescent antibody test (IFAT) the monoclonals did not react with B microti or B bovis. The monoclonals in IFAT gave high titres with the rat-adapted strain of B divergens, but showed variable reactivity with field isolates of the parasite indicating antigenic diversity in this parasite. Two of the monoclonals, as ascitic fluid, were protective against the rat-adapted strain in splenectomised rats.

Animals↗

PubMed1984

Kwashiorkor.

Kwashiorkor kills millions of young children in the tropical Third World. It was believed to be a disease of protein starvation. The medical team headed by Professor Ralph Henrickse of the Liverpool School of Tropical Medicine has discovered that aflatoxin, a fungus toxin, may be the triggering factor in this disease which also impairs liver function. In New Zealand, we have a pasture fungus, the spores of which produce a liver toxin that has killed millions of animals this century and impaired the performance of millions more. New Zealand is a pastoral farming country with 70 million sheep and several million cattle. We now protect the animal with zinc medication. This paper describes the similarities between Kwashiorkor and the mycotoxic liver disease in New Zealand livestock, known locally as Facial Eczema. It describes briefly my discovery that pharmacological doses of zinc protected farm animals from pasture contaminated with the spores of the fungus Pithomyces chartarum, which contains the toxin sporidesmin. This paper proposes that Kwashiorkor and Facial Eczema are diseases with similar beginnings and a common end.

Aflatoxins↗

PubMed1983

Scurvy: old disease--new insight.

Scurvy was once the number one killer of seafarers on long voyages. One early theory with widespread acceptance was that rancid fat caused scurvy. I propose to show that rancid fat did, indeed, predispose seafarers to scurvy. I propose to show that Captain Cook's successful voyages in the latter half of the eighteenth century were in part due to removal of rancid fat from the diet of his crew and in part due to dietary anti-scorbutic factors.

Dietary Fats↗

PubMed1981

The pharmacological role of zinc: evidence from clinical studies on animals.

Understanding the roles of zinc in the liver is likely to lead to improved therapy of some clinical conditions. Zinc appears to stimulate protein synthesis in the liver where it increases the binding and inhibits the degradation of insulin. Stimulating or maintaining protein synthesis in the liver is crucial to the outcome of parturition, injury or hepatotoxin challenge. A critical liver protein in circulatory collapse is angiotensinogen. This paper describes the observations of animal responses, in a practical farm situation, to zinc medication.

Animals↗