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Biomedical subjects

J W Gerrard

Publications and source records attributed to J W Gerrard.

At least 37 records · Page 2Linked to original sources
PubMed1980

X-linked mental retardation: a study of 7 families.

Seven families with X-linked mental retardation (MR) have been studied clinically and cytogenetically. All affected males in six of the families were found to have a fragile site on Xq in a number of their peripheral lymphocytes. The fragile site was not seen in any of the affected males in the seventh family. The affected males in the six families with the fragile X had a syndrome characterized by a variable degree of MR, macro-orchidism, a characteristic repetitive, jocular speech, normal body proportions, and large jaws and ears. The fragile X chromosome could only be detected in a proportion of female carriers and its frequency in females was found to be correlated with their mental status to be inversely correlated with their age.

Adolescent↗
PubMed1980

X-linked mental retardation: Renpenning revisited.

Nine men with X-linked mental retardation (MR) belonging to the family originally described by Renpenning and his colleagues have been reexamined and restudied. None of these men have the fragile X chromosome, and none have macro-orchidism; their testes range in size from small to average. All but one are severely retarded; one has an IQ of 70, the mean IQ of the remainder is 30 with a range of 18 to 45. They are short in stature, have small or normal-size ears and lower jaws, and a moderate degree of microcephaly, the mean skull circumference being just below two standard deviations from the normal.

Female↗
PubMed1980

Increased nonspecific bronchial reactivity in cigarette smokers with normal lung function.

Seventeen lifetime nonsmoking male teachers and 17 smoking male teachers with normal lung function were compared. The smokers showed a significantly greater prevalence of cough (p < 0.01), sputum production (p < 0.05), and wheezing (p < 0.01), but not dyspnea. There was no difference in the prevalence of a history of allergy, or the number of positive reactions to allergy prick skin tests, or in elevated serum IgE. Lung volumes, expiratory flow rates, specific airway conductance (SGaw), and the slope of phase III of the single breath O2 test were not significantly different. The geometric mean provocation concentration of histamine required to reduce the SGaw by 35% (PC35) was significantly lower in the smokers (1.84 mg/ml) than in the nonsmokers (4.83 mg/ml) (p < 0.005). Increased nonspecific bronchial reactivity may be a factor contributing to the development of airway obstruction in smokers.

Bronchi↗
PubMed1980

Increased bronchial reactivity to inhaled histamine in nonsmoking grain workers with normal lung function.

We measured nonspecific bronchial reactivity to inhaled histamine in 26 lifetime nonsmoking grain handlers and 29 lifetime nonsmoking unexposed control subjects matched for age, sex and specific conductance. Routine lung function tests revealed a total lung capacity that was higher in control subjects than in workers (P less than 0.05) with no difference in other subdivisions of lung volume, or expiratory flow rates between the two groups. An index of allergy was significantly greater in the control subjects than in the grain workers (P less than 0.01). None of the grain handlers was sensitive to grain dust by history or by skin tests. Respiratory symptoms (cough, sputum, dyspnea, or wheezing) were more prevalent in the grain workers than in controls (P less than 0.05). The mean concentration of histamine required to reduce the specific conductance by 35 percent was 4.5 +/- 2.0 mg/ml in grain workers and 5.9 +/- 3.0 mg/ml in controls (P less than 0.05). Chronic exposure to grain dust in nonallergic individuals appears to be associated with both increased prevalence of respiratory symptoms and increased nonspecific bronchial reactivity when compared to nonexposed control subjects.

Adult↗
PubMed1980

Immunoglobulin levels in smokers and non-smokers.

Immunoglobulin levels were compared in smoking and non-smoking grain handlers and teachers. Mean IgC and IgM levels were significantly lower, and IgE levels were significantly higher, in the smokers than in the non-smokers. IgA levels were also lower but with the numbers studied not significantly so. IgD levels were unchanged.

Adult↗
PubMed1979

Oral cromoglycate: its value in the treatment of adverse reactions to foods.

Thirty-two patients who reacted adversely to foods were given oral cromoglycate and placebo separately for two periods of seven days each. Adverse reactions were prevented by cromoglycate alone in 24. The symptoms responding to cromoglycate affected not only the gastrointestinal tract but also the skeletal, vascular and nervous systems.

Child↗
PubMed1979

Cow's milk allergy: a critical review.

Foods which are ingested frequently, and cow's milk in particular, are a common cause of delayed-in-onset allergy. Difficulty in diagnosing milk allergy is encountered because: (1) skin tests are unreliable; (2) the symptoms of milk allergy are frequently delayed in appearing, thereby obscuring their connection with the previously ingested food; (3) when such symptoms do appear, they often fail to suggest allergy as etiologic; and (4) the offending antigen may be present in a milk product not obviously associated with milk per se such as sherbet or cheese. Contrary to common belief, most milk (and other food) allergy is not reagin (IgE) mediated. Milk allergy is not confined to infancy, but is frequently seen in children and adults, often persisting as an allergy which had supposedly been "outgrown." Since milk allergy is often a familial disorder, its presence in a patient can assist the physician in possibly discovering it in other members of the family. A two or three-week trial elimination of milk, in conjunction with written dietary instructions for the patient, is presently the only reliable diagnostic procedure.

Adolescent↗
PubMed1979

Nonsmoking grain handlers in Saskatchewan: airways reactivity and allergic status.

This study was carried out to determine whether respiratory disease in Saskatchewan grainhandlers was or was not due to hypersensitivity to grain dust. Sixty nonsmoking grainhandlers, half of whom had low FEV1/FVC ratios and half of whom had high, were studied. The findings in grainhandlers were compared with those in 30 age-matched, nonsmoking teachers. In the group of grainhandlers with low FEV1/FVC ratios, one had developed asthma associated with exposure to grain dust. The majority were healthy, had FEV1/FVC ratios of 70% or greater, and had less evidence of allergic respiratory disease than had age-matched teachers. The studies suggest that non-atopic, nonsmoking men can work in grain elevators without developing respiratory disability, though they may develop a small but significant increase in nonspecific bronchial reactivity to histamine.

Agricultural Workers' Diseases↗
PubMed1978

Oral cromoglycate in treatment of adverse reactions to foods.

20 subjects with adverse reactions to foods were given oral cromoglycate and placebo separately for seven days each. While on each medication they were given, for four consecutive days, a food to which they were sensitive. Adverse reactions were prevented in 14 subjects. These results suggest that oral cromoglycate is of value in the treatment of some patients with adverse reactions to foods.

Administration, Oral↗
PubMed1978

A genetic study of immunoglobulin E.

Path analysis gives evidence of genetic heritability (.425) for serum IgE levels. Complex segregation analysis indicates, in addition to significant polygenic heritability, a major regulatory locus RE, with homozygotes re/re maintaining persistently high levels of IgE. The gene frequency of re is .489, and the displacement is 1.67 standard deviations.

Female↗