RFLPs of the APOB gene: comparative study between Greeks and southern Italian peoples

Restriction fragment length polymorphisms (RFLPs) at codons 2488 (XbaI), 3611 (MspI), and 4154 (EcoRI) of the apolipoprotein B gene were investigated in sample groups from Athens (Greece) and Calabria (southern Italy) to verify whether the distribution of the APOB gene variants in Calabria, where Greek colonization occurred in the eighth century B.C., reflects that of the present Greek population. A sample from Apulia, a southern Italian region having a history different from that of Calabria, was also analyzed. Three specific DNA regions, each containing the polymorphic site, were amplified by polymerase chain reaction on 243 samples, and the restriction data for the three groups were compared. The allelic frequencies of the samples from Apulia and Greece showed variability patterns that agree with those found in Caucasians, whereas the Calabrian sample shows remarkable peculiarities, mainly for the EcoRI RFLP. Linkage disequilibrium analyses of pairs of markers showed strong D linkage values between X-M markers, whereas the D linkage values between M-R markers were too small to be reliably estimated. Last, for both Apulians and Greeks, X-R markers showed linkage disequilibrium, whereas for Calabrians they did not. Estimates of XMR haplotypic frequencies were computed; they were found to be appreciably different between Calabrian and Greek samples, whereas the frequencies in the Apulian sample were approximately midway between those in Calabrians and Greeks.

Normality, deviance and minor psychiatric morbidity in the community. A population-based approach to General Health Questionnaire data in the Health and Lifestyle Survey

This paper investigates factors affecting the distribution of psychiatric morbidity in the community. It identifies a close relationship between mean Chronic General Health Questionnaire (CGHQ) scores in subdivisions of a large random sample of the community (the Health and Lifestyle Survey, N = 6317) and the prevalence in these groups of abnormal, above-threshold CGHQ scores. The frequency distributions of CGHQ scores in these different populations move up and down as a whole: like other physiological and behavioural attributes, these mental health outcomes in individuals are associated with characteristics of the populations in which they arise. Populations thus carry a collective responsibility for their own mental health and well-being. This implies that explanations for the differing prevalence rates of psychiatric morbidity must be sought in the characteristics of their parent populations; and control measures are unlikely to succeed if they do not involve population-wide changes.

Effects of neurotensin and neuropeptide Y on coronary circulation and myocardial function in dogs

This study analyzed the effects of the neuropeptides, neurotensin, and human and porcine analogue, neuropeptide Y, in anesthetized open-chest dogs. The left anterior descending coronary artery was cannulated and perfused at constant pressure via a blood reservoir. Flow to the coronary cannula was measured by an electromagnetic flowmeter, and regional segment lengths were measured by sonomicrometer crystals. Neurotensin injected into the coronary cannula resulted in a dose-dependent increase of coronary flow; neuropeptide Y resulted in a decrease of coronary flow. Because these changes in flow were not explained by systemic hemodynamic effects or alterations in regional myocardial function, they were considered to be coronary dilatation or constriction. Coronary dilatation by neurotensin was not prevented by alpha- or beta-adrenoceptor blockade but was completely abolished by indomethacin or by lowering coronary perfusion pressure to 35 mmHg when depressed systolic segment shortening indicated myocardial ischemia. Coronary constriction by neuropeptides Y persisted at coronary perfusion pressure of 35 mmHg and was only attenuated by indomethacin. We conclude that in contrast to systemic effects, coronary vasodilatation by neurotensin is mediated by a prostanoid product of cyclooxygenase. Preactivation of the prostaglandin system may explain why neurotensin lost its coronary dilator effect during myocardial ischemia. Neuropeptide Y may elicit coronary constriction in addition to mechanic reduction of coronary flow resembling severe coronary stenosis.

The Small Area Health Statistics Unit: a national facility for investigating health around point sources of environmental pollution in the United Kingdom

STUDY OBJECTIVE

The Small Area Health Statistics Unit (SAHSU) was established at the London School of Hygiene and Tropical Medicine in response to a recommendation of the enquiry into the increased incidence of childhood leukaemia near Sellafield, the nuclear reprocessing plant in West Cumbria. The aim of this paper was to describe the Unit's methods for the investigation of health around point sources of environmental pollution in the United Kingdom.

DESIGN

Routine data currently including deaths and cancer registrations are held in a large national database which uses a post code based retrieval system to locate cases geographically and link them to the underlying census enumeration districts, and hence to their populations at risk. Main outcome measures were comparison of observed/expected ratios (based on national rates) within bands delineated by concentric circles around point sources of environmental pollution located anywhere in Britain.

MAIN RESULTS

The system is illustrated by a study of mortality from mesothelioma and asbestosis near the Plymouth naval dockyards during 1981-87. Within a 3 km radius of the docks the mortality rate for mesothelioma was higher than the national rate by a factor of 8.4, and that for asbestosis was higher by a factor of 13.6.

CONCLUSIONS

SAHSU is a new national facility which is rapidly able to provide rates of mortality and cancer incidence for arbitrary circles drawn around any point in Britain. The example around Plymouth of mesothelioma and asbestosis demonstrates the ability of the system to detect an unusual excess of disease in a small locality, although in this case the findings are likely to be related to occupational rather than environmental exposure.

Incidence of cancers of the larynx and lung near incinerators of waste solvents and oils in Great Britain

The Small Area Health Statistics Unit (SAHSU) is a new independent facility for the investigation of disease near industrial installations in the UK. SAHSU analysed the incidence of cancers of the larynx and lung near the incinerator of waste solvents and oils at Charnock Richard, Coppull, Lancashire (which operated between 1972 and 1980) and nine other similar incinerators in Great Britain, after reports of a cluster of cases of cancer of the larynx near the Charnock Richard site. Postcoded cancer registration data were available for 1974-84 in England and Wales and 1975-87 in Scotland. Lag periods of 5 and 10 years were used between start-up (or first registration) of the incinerators and cancer incidence. Standardised observed/expected (O/E) ratios were assessed within 3 km and 3-10 km of each site and then aggregated over all sites. Expected values were based on national rates (regionally adjusted) with and without stratification by Carstairs' index, a measure of the socioeconomic profile of areas that uses census data for enumeration districts. Data were also assessed over a range of circles up to 10 km to test for trend in O/E ratios with distance. For Charnock Richard, none of the O/E ratios within 3 km or from 3-10 km differed significantly from unity, for either cancer or lag period. In the analysis of all sites with stratification by Carstairs' index, none of these O/E ratios differed significantly from unity for the two cancers. There was no evidence of decreasing risk with distance from the sites of either cancer. We conclude that the apparent cluster of cases of cancer of the larynx reported near Charnock Richard was unlikely to be due to its former incinerator.

Benzyl benzoate moist powder: investigation of acaricidal [correction of acarical] activity in cultures and reduction of dust mite allergens in carpets

Despite advances in the understanding of dust mites, it remains difficult to control exposure to mite allergens, and it is particularly difficult to reduce mites in fitted carpets or sofas. Several chemicals have been demonstrated to kill mites or denature mite allergens, and some of these chemicals have been investigated in carpets. Benzyl benzoate (BB), which has been widely used to kill scabies mites and is known to kill mites of the genus Dermatophagoides, has been used as a method of treating carpets. The present article describes experiments in the laboratory and in houses in testing two preparations of BB, a moist powder and a foam. The moist powder is composed of two ingredients, a wetted "inert" cellulose, which is designed to act as a cleaning agent, and the active BB adsorbed onto silicates. The active powder kills 90% of mites in culture within 12 hours and 100% in 24 hours, whereas the cellulose is not acaricidal. The moist-powder preparation was highly effective at killing D. farinae and D. pteronyssinus mites in the laboratory. In carpets the moist powder, applied for 12 hours with repeated brushing, was demonstrated to reduce the concentrations of group I and group II dust mite allergens in dust recovered at 1 month. This decrease in concentration could, in part, be explained by a persistent increased recovery of dust caused by residual white powder. However, when the recovery of group II allergens was calculated as the total allergen recovered, the decrease was highly significant at 2 weeks and 4 weeks after treatment (p less than 0.001). Application of the powder to carpets for 4 hours or of the foam to sofas was less effective. After 2 months the effect on mite antigen in carpets was still present, but some increase was apparent, suggesting that repeat application after 2 or 3 months would be necessary to control mite-allergen levels.

Randomised controlled trial of anti-smoking advice: final (20 year) results

STUDY OBJECTIVE

The aim was to measure experimentally the effects in middle aged men of stopping smoking.

DESIGN

The study was a randomised controlled trial.

SETTING AND SUBJECTS

The subjects were 1445 male smokers, initially aged 40-59 years, who were selected from the Whitehall study survey of 16,016 civil servants on the basis of a high risk of cardiorespiratory disease.

MAIN RESULTS

During the next 20 years there were 620 deaths (231 from coronary heart disease), 96 cases of lung cancer, and 159 other cancers. Comparing the intervention with the normal care group, total mortality was 7% lower, fatal coronary heart disease was 13% lower, and lung cancer (deaths+registrations) was 11% lower. An excess rate for other cancers, reported previously, did not persist into the second decade of the trial.

CONCLUSIONS

The results are consistent with observational studies, implying that smoking cessation by middle aged men substantially improves their changes of avoiding lung cancer or a fatal heart attack. Our estimate from the trial is that out of every 100 men who stopped smoking, between six and 10 were in consequence alive 20 years later.

Plasma cholesterol concentration and mortality. The Whitehall Study

OBJECTIVE--To examine the relationship between plasma cholesterol concentration and mortality from major causes of death.

DESIGN

--Cohort study. SETTING--Civil service offices in London, England. PARTICIPANTS--There were 17,718 male civil servants aged 40 through 64 years at the time of study entry between 1967 and 1969. MAIN OUTCOME MEASURE--Mortality from major cause groups. RESULTS--There were 4022 deaths in the cohort over the 18 years of follow-up. Total mortality increased with cholesterol level, although mortality in the small group with very low cholesterol levels (5% of study population) was nonsignificantly higher (P greater than .5) than that of the remainder of the lowest quintile cholesterol group. Coronary heart disease mortality increased with increasing cholesterol concentration from the lowest levels (P less than .001 for trend). The cancer mortality rate in the group below the fifth centile of the cholesterol distribution was higher than in the remainder of the cohort for lung (P less than .001), pancreas (P = .05), liver (P = .09), and all smoking-related cancers (P = .02). Only for lung cancer was there a consistent inverse trend with cholesterol level (P less than .01). Rates of mortality due to non-neoplastic respiratory disease were inversely related to cholesterol level (P less than .001). Health state at the time of examination and socioeconomic position were related to cholesterol concentration--subjects in lower employment grades, with disease at baseline, with a history of recent unexplained weight loss, or who had been widowed had lower initial cholesterol levels. These associations largely accounted for the relationships between cholesterol level and noncardiovascular mortality. CONCLUSIONS--The inverse associations between plasma cholesterol concentration and mortality from certain causes of death seen in cohort studies could be because the participants with low cholesterol levels possess other characteristics that place them at an elevated risk of death.

An improved graphical method for pattern recognition from spike trains of spontaneously active neurons

Spontaneous activity and rhythmical oscillations are common features of large neuronal networks in mammals. Detection of repetitive spike patterns or pacemaker activity during electrophysiological recording of spontaneous action potentials from single neurons can be difficult if a "noisy" background is present. This paper describes an improved method for an online spike train analysis based on joint interval histograms (JIH, Rodiek et al. 1962). By means of higher ordered JIH the discrimination of spike patterns with repetitive bursting activity or oscillations is possible even when randomly distributed action potentials appear. Examples of simulated spike trains and those recorded from cultured hippocampal neurons are presented.

ABC of vascular diseases. Epidemiology of atherosclerosis

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Emergency admissions under Section 4 of the Mental Health Act 1983: reasons for a high rate

One of the aims of the Mental Health Act 1983 was to discourage the use of emergency orders; the criteria for using the emergency provisions provided by Section 4 of the Act are stricter than those of the corresponding Section 29 of the previous Mental Health Act 1959. In 1986-87 the Mental Health Act Commissioners found a comparatively high level of admission under Section 4 in Cambridge. This study was undertaken to examine the hospital careers of all Section 4 admissions in Cambridge over a two-year period, and to compare these with admissions for assessment by two doctors under Section 2 of the 1983 Act and informal admissions. Almost 50% of all the Section 4 admissions were not continued on a compulsory admission by the end of the 72 hour duration of the Section. The findings suggest that these patients might have been more appropriately admitted informally or not at all.

The assessment of the relationship between blood pressure and sodium intake using whole-day, daytime and overnight urine collections

The usefulness of whole-day, daytime (waking to retiring time) and overnight urine samples for assessing the relationship between blood pressure and sodium intake was examined in 301 male London civil servants, aged from 37 to 58 years old. Systolic blood pressure (SBP)/diastolic blood pressure (DBP) averaged 126/78 mmHg and the 24-h urinary excretion of sodium and potassium was 174 and 73 mmol, respectively. There was poor consistency between day- and night-time urine samples with respect to both sodium and potassium content. The urinary excretion of sodium and potassium was lower (P less than 0.001) in overnight than in daytime samples. After standardization for creatinine, the night: day ratio was 0.79 for sodium output and 0.55 for potassium excretion. Blood pressure, adjusted for age and body mass index, was significantly and positively correlated with overnight sodium excretion (SBP/DBP: slope = 0.061/0.046 mmHg/mmol) whereas the correlations with sodium excretion in daytime (0.010/0.004 mmHg/mmol) and whole-day (0.024/0.016 mmHg/mmol) urine samples were not significant. Blood pressure was significantly correlated with the sodium:potassium ratio in whole-day urine (1.941/1.968 mmHg/unit). As the agreement between daytime and overnight urine samples was low with respect to both sodium and potassium content, and due to the fact that the relationship between blood pressure and sodium in overnight samples may at least partially reflect pressure diuresis, overnight urinary sodium, even if related to sodium intake, cannot be employed to assess the association between salt in the diet and blood pressure.

AcyI-RFLP identified on an amplified region of the TPO gene

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Socioeconomic differentials in cancer among men

The relationship between cancer and socioeconomic position is examined for men using data from three sources--the Whitehall Study of London civil servants, the OPCS Longitudinal Study and the Registrar General's Decennial Supplement. Mortality from, or registration for, malignant neoplasms was higher overall in lower socioeconomic groups. There was considerable variation in the strength, and to a lesser extent direction, of the association of specific cancer sites and socioeconomic position within each of the studies. However, between the studies the relationships between socioeconomic position and the particular cancers were very similar. The similarity in results, taken in conjunction with the differences in design and methods of the three studies, makes it very unlikely that these consistent associations are due to artefacts. The heterogeneity in relationships between specific cancer sites and socioeconomic position suggests that no single factor--such as differences in general susceptibility or differences in smoking behaviour--can account for these associations. However socioeconomic differentials displayed by a particular malignancy do offer clues to its aetiology, and provide an indication of the scope that exists for reducing the burden of cancer within a population.

Overweight and stroke in the Whitehall study

STUDY OBJECTIVE

The aim was to examine the risk of increasing overweight for death from stroke.

DESIGN

This was a prospective cohort study, in which the main outcome measure was the mortality ratio for stroke with increasing body mass index.

SETTING

Civil service departments, Whitehall, London.

SUBJECTS

Participants were 17,753 men aged 40 to 64 years.

MEASUREMENTS AND MAIN RESULTS

208 stroke deaths were recorded. Men aged 40 to 54 in the most overweight quintile of body mass index had a mortality ratio of 2.01 (95% confidence interval 0.9 to 4.7) compared to the thinnest quintile. The mortality ratio was 1.19 (95% CI 0.7 to 2.0) in men aged 55 to 64. The increase in risk was more apparent in non-smokers: age adjusted mortality ratio 2.58 (95% CI 1.2 to 5.7). When smoking status and overweight were considered in combination a gradient of the age adjusted mortality ratio was observed, from 1.0 in thinner/non-smokers up to 3.15 in fatter/current smokers. On the assumption that smoking and obesity cause strokes, an estimated 60% of strokes could be prevented if these two easily identifiable risk factors could be avoided.

CONCLUSIONS

The risks of overweight for death from stroke were more apparent in younger subjects and non-smokers. A substantial proportion of stroke deaths occurring under the age of 80 years would probably be prevented if cigarette smoking and overweight could be avoided.

Contralateral tension pneumo/hemothorax resulting from left subclavian vein cannulation under general anesthesia

A patient had a subclavian vein catheter placed under general endotracheal anesthesia with positive pressure ventilation. During placement, the superior vena cava, pleura, and pulmonary tissue were punctured, resulting in a tension pneumo/hemothorax, the detection of which was complicated by its slow onset and unusual location. The lesion required an emergent thoracotomy for repair.