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Biomedical subjects

T M Allan

Publications and source records attributed to T M Allan.

At least 19 recordsLinked to original sources
PubMed1998

Acute pulmonary hemorrhage in infants associated with exposure to Stachybotrys atra and other fungi.

BACKGROUND: A geographic cluster of 10 cases of pulmonary hemorrhage and hemosiderosis in infants occurred in Cleveland, Ohio, between January 1993 and December 1994. STUDY DESIGN: This community-based case-control study tested the hypothesis that the 10 infants with pulmonary hemorrhage and hemosiderosis were more likely to live in homes where Stachybotrys atra was present than were 30 age- and ZIP code-matched control infants. We investigated the infants' home environments using bioaerosol sampling methods, with specific attention to S atra. Air and surface samples were collected from the room where the infant was reported to have spent the most time. RESULTS: Mean colony counts for all fungi averaged 29 227 colony-forming units (CFU)/m3 in homes of patients and 707 CFU/m3 in homes of controls. The mean concentration of S atra in the air was 43 CFU/m3 in homes of patients and 4 CFU/m3 in homes of controls. Viable S atra was detected in filter cassette samples of the air in the homes of 5 of 9 patients and 4 of 27 controls. The matched odds ratio for a change of 10 units in the mean concentration of S atra in the air was 9.83 (95% confidence interval, 1.08-3 X 10(6)). The mean concentration of S atra on surfaces was 20 X 10(6) CFU/g and 0.007 x 10(6) CFU/g in homes of patients and controls, respectively. CONCLUSION: Infants with pulmonary hemorrhage and hemosiderosis were more likely than controls to live in homes with toxigenic S atra and other fungi in the indoor air.

Acute Disease↗
PubMed1996

Seasonality and the sudden infant death syndrome during 1987-9 and 1991-3 in Australia and Britain.

OBJECTIVE: To determine whether seasonality of the sudden infant death syndrome persists now that rates have fallen, mostly after widespread adoption of the "face upwards" sleeping position. DESIGN: Monthly data on the sudden infant death syndrome during 1987-9 were compared for seasonality with those of 1991-3; rates were studied as deaths per 1000 live births. SETTING: Australia and Britain (England, Wales, and Scotland). SUBJECTS: Infants under 1 year dying of the syndrome (2401 for Australia and 6630 for Britain). MAIN OUTCOME MEASURE: Extent of seasonal variation (amplitude) was established by cosinor analysis; amplitudes for the earlier and later years were compared. RESULTS: The rate fell in every month, and, though it did so relatively more in winter than summer, seasonality remained a distinctive feature. In the comparison of amplitudes the ratio between the earlier and later years was 1.4 in both Australia and Britain. Some differences between the hemispheres were noted. CONCLUSIONS: Seasonality of the sudden infant death syndrome remains to be explained and continues to be an important aetiological lead. Studies from other countries are needed.

Australia↗
PubMed1996

Seasonality of birth in sudden infant death syndrome.

The objective was to clarify the optimal birth month for avoidance of SIDS and the seasonal characteristic of each birth-month cohort. The statistical method was cosinor analysis, and this established seasonality of SIDS death and births, the extent of this seasonality (amplitude) and the position of the peak (acrophase). There is a lowering of risk, by one third, amongst babies born in February-May compared to those born in August-November. The seasonal variation of death was twice as great for birth in September as compared with those in April. Those born in May-June lived on average six weeks longer than those born in November-April. Advice on subsequent pregnancy delivery date should be given to families who have already experienced SIDS. For those born in autumn there may be two components-the first a genetic or intrauterine component independent of month of birth, and the second an independent effect of interaction with winter environment.

Cohort Studies↗
PubMed1995

Seasonal variation in coronary heart disease in Scotland.

STUDY OBJECTIVE: Seasonality of coronary heart disease (CHD) was examined to determine whether fatal and non-fatal disease have the same annual rhythm. DESIGN: Time series analysis was carried out on retrospective data over a 10 year period and analysed by age groups ( < 45 to > 75 years) and gender. SETTING: Data by month were obtained for the years 1962-71. The Registrar General provided information on deaths and the Research and Intelligence Unit of the Scottish Home and Health Department on hospital admissions. SUBJECTS: In Scotland, between 1962 and 1971, 123 000 patients were admitted to hospital for CHD, of whom 29 000 died. There were a further 97 000 CHD deaths outside hospital. These two groups were also examined as one (coronary incidence) - that is, all coronary deaths and coronary admissions discharged alive. STATISTICAL ANALYSIS AND MAIN RESULTS: Where there was a single annual peak, the sine curve was analysed by cosinor analysis. When there were two peaks the analysis was by normal approximation to Poisson distribution. In younger men (under 45 years) admitted to hospital there was a dominant spring peak and an autumn trough. A bimodal pattern of spring and winter peaks was evident for hospital admissions in older male age groups: with increasing age the spring peak diminished and the winter peak increased. In contrast, female hospital admissions showed a dominant winter/summer pattern of seasonal variation. In male and female CHD deaths seasonal variation showed a dominant pattern of winter peaks and summer troughs, with the winter peak spreading into spring in the two youngest male age groups. CHD incidence in women showed a winter/summer rhythm, but in men the spring peak was dominant up to the age of 55. CONCLUSION: The male, age related spring peak in CHD hospital admissions suggests there is an androgenic risk factor for myocardial infarction operating through an unknown effector mechanism. As age advances and reproduction becomes less important, the well defined winter/summer pattern of seasonal variation of CHD is superimposed, and shows a close relationship with the environment, especially temperature, or the autumn and early winter fall in temperature.

Adult↗
PubMed1995

Common obstacles to the daily functioning of pediatric traumatically brain injured patients: perceptions of caregivers and psychologists.

Common difficulties encountered by patients with pediatric traumatic brain injuries (referred to hereafter as pediatric TBI patients) were identified, and the congruence between caregiver and professional perceptions of these problems was examined. Forty-seven caregivers identified 118 obstacles experienced in the care of their pediatric TBI patients. Another sample of 46 caregivers cross-validated these problems by rating each for its frequency and difficulty. Items were tank ordered by their composite score, a derived measure obtained for each item by cross-multiplying the frequency and difficulty ratings. Twenty psychologists who work with pediatric TBI patients also rated each of the 118 problem situations. A modest correlation (tau = .28, p < .001) between the two groups' rank orders of the problem situations, although significant, suggests that there are discrepancies between caregiver and professional perceptions of problem situations. Items perceived as most common and difficult by caregivers often received far lower ratings by psychologists and vice versa. The results suggest that carefully evaluating individual patient concerns may contribute to more efficient use of professional resources and improved patient education and follow-up care.

Activities of Daily Living↗
PubMed1993

Changing seasonality of birth--a possible environmental effect.

STUDY OBJECTIVE: Seasonality of birth was examined to determine whether this has changed over the last half century. DESIGN: Time-series analysis was carried out on retrospective data, both for the full 50 year period and for the five decades within that period. Although the primary objective was to investigate seasonality by fitting an appropriate model and examining changes over the period studied, non-seasonal trends were also examined. SETTING: Data by month were obtained from the Registrar General on all births in Scotland during the years 1938-87. SUBJECTS: There was a total of 4,325,000 births in the 50 years examined. MEASUREMENTS AND MAIN RESULTS: There are two peaks to the seasonality rhythm--one wide, in spring/early summer and one narrow, in October. Cosinor analysis, modified to allow for the second peak, was used to fit a sine curve model. Analysis of variance showed that this was adequate and established the significance of both peaks. The main peak of seasonal excess rose to a maximum in 1948-57, and thereafter declined by two thirds. While the position of the main peak moved forward two months over the 50 years, the October peak remained unchanged until the final decade, when it rose slightly; thus its relative importance increased steadily from 1948 onwards. CONCLUSIONS: The changing biological rhythm may be related to alterations in the climate and environment or to social differences.

Analysis of Variance↗
PubMed1991

Seasonality of disease in Kuwait.

To compare the seasonal variation in total mortality and deaths from cardiovascular, respiratory, and malignant disease, data were collected from North-East Scotland (Grampian region) and Kuwait. Seasonal differences were similar, in both timing and degree, for total mortality and deaths from circulatory disease, but were greater in Kuwait for respiratory disease. Peak mortality was during winter in both areas: in Grampian, when the climate is most uncomfortable, and in Kuwait, when the climate is at its most comfortable. Socioeconomic changes in Kuwait have been accompanied by a rapid fall in the degree of seasonality (deseasonality) for both total and infant mortality. These findings suggest that mortality peaks in winter, not because of a seasonally low temperature, but because of a seasonal fall in mean temperature irrespective of the annual mean temperature.

Adult↗
PubMed1991

Composition of seasonality of disease.

The composition of the seasonality of total death was ascertained. Vascular disease seasonality constitutes more than half. The remaining seasonality is influenced by respiratory disease. Surprisingly and of possible importance cancer mortality was not seasonal. Deaths from 'all other disease' and from 'injuries' is seasonal. Seasonality increases with age. In coronary and cerebrovascular disease death has a large seasonal fluctuation. On the other hand hospital admissions and survivors have a minor seasonal fluctuation--only cerebrovascular admissions reaching the chosen level of significance with a small seasonal amplitude. For vascular disease the ranking of seasonal fluctuation from greatest to least is--death outside hospital, total death, death inside hospital, admissions, survivors. It is death outside hospital presumably 'sudden' that imposes seasonality on coronary disease in general. For respiratory diseases not only death but hospital admissions and survivors have high amplitude seasonality with a much greater fluctuation than for death in vascular disease.

Aged↗
PubMed1990

Seasonal, regional and secular variations of cardiovascular and cerebrovascular mortality in New Zealand.

Numbers of deaths from coronary heart disease (CHD) and cerebrovascular disease (CVD) were available for five years (1980-84) in the North and South Islands of New Zealand; estimated death rates were determined, and age correction made. There was a major seasonal variation by month in coronary and cerebrovascular deaths in both sexes and both islands, with a zenith in June/July/August (winter) and a nadir in December/January/February (summer). There was a less obvious, and less complete, linear trend, with declining secular (annual) mortality over the five years. This was more obvious in North Island but not proven in South Island. After standardising for age, coronary mortality rates (but not cerebrovascular mortality rates), were significantly higher in South Island than in North Island. Mortality from both CHD and CVD was significantly higher in males than in females.

Age Factors↗
PubMed1986

Iconic memory and aging.

Previous attempts to measure the capacity of iconic memory in elderly adults have been unsuccessful, demonstrating in one case that 80% of the elderly adults tested could not perform above chance level. The present experiments illustrated that the partial report paradigm designed by Sperling (1960) could be used with elderly adults to obtain such a measure. Both the young and older adults exhibited a strong partial report superiority that declined with delays in the cue interval. The effect of the perceived organization of an array on readout from iconic memory also was examined. Contrary to Merikle (1980), the differences due to the display layout were attributed to better acuity for one type of display and not to perceptual organization factors.

Acoustic Stimulation↗
PubMed1977

ABO and Rh blood groups in relation to sex ratio, mean number and mortality of sibs.

Data are presented on the sex ratio, mean number and mortality of the sibs of 17,060 schoolchildren, and on the sex ratio and mean number of the sibs of 5,785 blood donors, in relation to the children's and donors' sex and ABO and Rh blood groups. The sex ratio is significantly higher for the sibs of AB + B than for those of A + O schoolboys, and for the sibs of Rh-negative than for those of Rh-positive male blood donors, but in both cases the mean number of sibs is exactly the same for the first-mentioned as for the second-mentioned category.

ABO Blood-Group System↗
PubMed1976

Interrelations between ABO blood group, plasminogen, alpha1-antitrypsin, alpha2-macroglobulin and the platelet count in blood donors.

The level of plasminogen alpha1-antitrypsin, alpha2-macroglobulin and the platelet count were measured in 511 blood donors. The mean level of alpha1-antitrypsin was significantly lower in men of group B compared with that of group O. No other differences between the blood groups reached statistical significance. Woman had higher mean levels of alpha1-antitrypsin and alpha2-macroglobulin and a higher platelet count than men. The levels of plasminogen and alpha1-antitrypsin were significantly higher in women using oral contraceptive compared with those who were not. The level of alpha2-marcoglobulin fell with age until the 60-64 year age-group in men and the 40-49 year age-group in women. A positive correlation existed between the alpha1-antitrypsin and the alpha2-macroglobulin level and between the platelet count and the plasminogen level.

ABO Blood-Group System↗
PubMed1975

ABO blood groups and human sex ratio at birth.

In the aggregate of the seventeen published series of the ABO blood groups of newborn babies and their mothers (an aggregate totalling 53,679 mother-baby combinations) there are substantial reciprocal differences by maternal ABO blood group in respect of the ratio of male to female babies. The ratio is relatively low for AB babies of AB mothers plus A babies of A mothers, but is relatively high for non-AB babies of AB mothers plus non-A babies of A mothers. By contrast, the ratio is relatively high for O babies of O mothers plus B babies of B mothers, but (except in the aggregate of seven of the seventeen series, totalling 16,601 cases) is relatively low for non-O babies of O mothers plus non-B babies of B mothers. Disregarding the babies' blood groups, the sex-ratio is higher for higher for babies of AB than of non-AB mothers. Disregarding the mothers' blood groups, the sex ratio is lower for A than non-A babies, while in the author's own series, included above, the ratio is lower for A babies possessing than for those not possessing detectable A1 antigen. It is suggested that a possible cause of these differences is sex-differential fetal mortality caused by interaction of the ABO genes, and some of the sex-determining genes, with oestrogen and progesterone.

ABO Blood-Group System↗