Moclobemide in the treatment of major depressive disorder (DSM-3) following traumatic brain injury

Major depression (MDD) following traumatic brain injury (TBI) is a common phenomenon. There are no adequate studies in the literature defining optimum treatments for this condition following TBI. The opportunity arose to analyse a group of patients who were included in a larger study of an antidepressant (moclobemide). As the treatment, but not the delivery, was known, this has the status of an open study. Twenty-six patients with major depression of late onset (mean 4.67 years post-TBI) were identified (18 male, 8 female), with a mean age at injury 28.49 years. The group was moderately depressed with Hamilton Depression score (HAM-D) of 23.385 and moderately anxious with Hamilton Anxiety score (HAM-A) of 21.231. Mean HAM-D reduction was 81% and HAM-A reduction 81%. Of the 26 subjects 23 were defined as responders. Onset of action was rapid, with 17 responding by day 3. Irritability scores showed a mean reduction of 57% and pain scores a reduction of 39%. It is concluded that moclobemide may be an effective treatment for MDD following TBI, but properly controlled studies must be carried out to confirm this.

Thyroid nodules, thyroid function and dietary iodine in the Marshall islands

BACKGROUND

Thyroid nodules have been found to be common in the population of the Marshall Islands. This has been attributed to potential exposure of radioiodines from the nuclear weapons tests on Bikini and Eniwetok between 1946 and 1958.

METHODS

In order to get a full picture of thyroid pathology in the Marshallese population potentially exposed to radioactive fallout we performed a large thyroid screening programme using palpation, high resolution ultrasound and fine needle biopsies of palpable nodules. In addition, various parameters of thyroid function (free T3, free T4, thyroid stimulating hormone [TSH]) and anti-thyroid antibodies were examined in large proportions of the total population at risk. Since dietary iodine deficiency is an established risk factor for thyroid nodules, iodine concentration in urine samples of 362 adults and 119 children was measured as well as the iodine content of selected staple food products.

RESULTS

The expected high prevalence of thyroid nodules was confirmed. There was no indication of an increased rate of impaired thyroid function in the Marshallese population. A moderate degree of iodine deficiency was found which may be responsible for some of the increased prevalence of thyroid nodules in the Marshallese population.

CONCLUSIONS

Studies on the relationship between exposure to radioiodines and thyroid nodules need to take dietary iodine deficiency into account in the interpretation of findings.

Dimerisation of maize glutathione transferases in recombinant bacteria

Two cDNAs encoding novel type III maize (Zea mays) GST subunits, ZmGST VI and ZmGST VII, have been cloned in addition to the previously described ZmGST V. Together with the type I GSTs ZmGST I and ZmGST III, these subunits were expressed in Escherichia coli, both individually and in tandem combinations using a customised pET vector. The GST dimers formed were then characterised. When type I GSTs were co-expressed only the respective homodimers were formed rather than the ZmGST I-III heterodimer. The failure to form this heterodimer, together with the negligible herbicide-detoxifying activity associated with recombinant ZmGST III-III, suggests that the identity of herbicide-detoxifying isoenzymes described in maize as being composed of ZmGST III subunits requires re-evaluation. In contrast, co-expression of the type III GSTs ZmGST V and ZmGST VI resulted in the formation of ZmGST V-V, ZmGST VI-VI and ZmGST V-VI dimers in the ratio 1:1:2 as predicted for random subunit association. ZmGST V-VI had kinetic characteristics intermediate between those of the two homodimers, indicating that the subunits were catalytically independent of one another. Co-expression of ZmGST V and ZmGST VII resulted in the formation of ZmGST V-VII and this isoenzyme was subsequently identified in maize plants. Attempts to dimerise type I GST subunits with type III GST subunits proved unsuccessful. These results demonstrate the utility of co-expressing recombinant GSTs to explore the potential of subunit-subunit associations and to help unravel the complexity of homodimeric and heterodimeric GSTs in plants.

An action plan for tobacco control at regional level

Smoking is the single biggest preventable cause of death in the UK; killing over 120 000 people each year, contributing to inequalities in health, exacerbating and causing poverty. Smoking has increased steadily among children since 1988 and more recently, among young adults. The current context in the UK is highly favourable for introducing comprehensive tobacco control measures. This paper summarises a regional action plan for tobacco control. Actions at district and regional levels are outlined to establish a comprehensive local tobacco control framework and complement national tobacco control measures. Measures include: a 'SWOT' analysis of current activity; systematic monitoring of smoking prevalence, attitudes to smoking, and the impact of tobacco control interventions; provision of effective smoking cessation support to a minimum standard throughout the health service; increased coverage of smoke-free public places and workplaces; enforcement of legislation on illegal sales to children and against smuggling and selling illegally imported tobacco; paid and unpaid mass media campaigns; and systematic lobbying for fiscal and legislative measures. One of the key components of the plan is the introduction of evidence-based tobacco control strategies at district levels. These should include a performance framework with clear organisational and managerial accountability and employ a co-ordinated, multiagency, partnership approach. Priority groups should be identified. Strategies should seek to engage the public to build support for tobacco control measures. Sufficient time, staff, resources and training must be allocated to tobacco control work and progress towards objectives monitored.

Donepezil overdose: a tenfold dosing error

OBJECTIVE

To report toxicity resulting from donepezil administration following a tenfold dosing error.

CASE SUMMARY

A 79-year-old white nursing home patient with a history of Alzheimer disease and hypertension was inadvertently given 50 mg of donepezil instead of her usual 5-mg dose. She presented to the emergency department with nausea, vomiting, and persistent bradycardia (HR in the 40s). Routine laboratory studies were all within normal limits. Basilar rales were noted five hours after arrival. She was treated with atropine 0.2 mg as needed for bradycardia (HR <50 beats/min); a total of 3.0 mg was administered over 18 hours. Each bolus kept her HR >60 beats/min for one-half to two hours. No further vomiting or evidence of pulmonary edema occurred after her initial episodes. She returned to baseline by day 2 (HR in the 70s) and was returned to the nursing home.

DISCUSSION

Donepezil is a centrally acting, reversible cholinesterase inhibitor that is used in the treatment of Alzheimer disease. Donepezil is highly specific for neural acetylcholinesterases, preferentially binding acetylcholinesterase by greater than three orders of magnitude over butyrylcholinesterases. This specificity minimizes peripheral adverse effects at therapeutic doses. Our patient mainly experienced bradycardia and had minimal secretory effects compared with what is usually seen with nonspecific cholinesterase inhibition. Medication errors like the one that produced this overdose are a common but preventable cause of morbidity in healthcare facilities.

CONCLUSIONS

A tenfold dosing error caused donepezil toxicity. The main effect of this overdose was bradycardia, which responded to atropine therapy.

Indexes for identification of abnormal tremor using computer tremor evaluation systems

We consider methods of formulating indexes to identify abnormalities in tremor appropriate for computerized tremor analysis systems. Characterization of amplitude, frequency, and "harmonicity" are considered as well as how to combine several such characteristics into a single index to discriminate normal from abnormal tremor effectively. The methodological issues discussed here should be of interest to researchers and clinicians working with tremor in general and to both users and developers of computer tremor analysis systems.

Teaching public health to medical students in the United Kingdom--are the General Medical Council's recommendations being implemented?

BACKGROUND

Despite frequent calls to improve undergraduate medical public health teaching, little is known about whether curricula have changed. We report a survey of undergraduate public health teaching in UK medical schools in 1996. The survey aimed to assess whether the General Medical Council's 1993 recommendations to strengthen undergraduate medical education in public health have been implemented.

METHODS

We asked heads of academic departments of public health at all 26 UK medical schools to complete a questionnaire and provide supporting documentation for each undergraduate public health course or module. We compared results from the 1996 survey with those from a similar survey in 1992.

RESULTS

Twenty-one out of 26 (81 per cent) medical schools responded. All responding medical schools included public health teaching within their curriculum. The median number of public health courses per medical school was unchanged since 1992. A wide variety of topics were taught. Core public health subjects were taught at most schools, though over a quarter of medical schools did not cover some core topics. Between 1992 and 1996 the proportion of time devoted to teaching by lectures decreased, whereas the following all increased: teaching by small group methods; the proportion of courses using methods of assessment encouraging active learning; and the contribution of public health courses to the final degree assessment.

CONCLUSION

The findings suggest that many of the General Medical Council's recommendations for improving the delivery of undergraduate education are being addressed by public health teaching in UK medical schools. However, addressing the gaps in undergraduate public health teaching revealed in this survey is a continuing challenge for academic public health departments. Medical schools should review the content of their undergraduate public health teaching to ensure that tomorrow's doctors are adequately equipped with public health knowledge and skills.

A role for glutathione transferases functioning as glutathione peroxidases in resistance to multiple herbicides in black-grass

Black-grass (Alopecurus myosuroides) is a major weed of wheat in Europe, with several populations having acquired resistance to multiple herbicides of differing modes of action. As compared with herbicide-susceptible black-grass, populations showing herbicide cross-resistance contained greatly elevated levels of a specific type I glutathione transferase (GST), termed AmGST2, but similar levels of a type III GST termed AmGST1. Following cloning and expression of the respective cDNAs, AmGST2 differed from AmGST1 in showing limited activity in detoxifying herbicides but high activities as a glutathione peroxidase (GPOX) capable of reducing organic hydroperoxides. In contrast to AmGST2, other GPOXs were not enhanced in the herbicide-resistant populations. Treatment with a range of herbicides used to control grass weeds in wheat resulted in increased levels of hydroperoxides in herbicide-susceptible populations but not in herbicide-resistant plants, consistent with AmGST2 functioning to prevent oxidative injury caused as a primary or secondary effect of herbicide action. Increased AmGST2 expression in black-grass was associated with partial tolerance to the peroxidizing herbicide paraquat. The selective enhancement of AmGST2 expression resulted from a constitutively high expression of the respective gene, which was activated in herbicide-susceptible black-grass in response to herbicide safeners, dehydration and chemical treatments imposing oxidative stress. Our results provide strong evidence that GSTs can contribute to resistance to multiple herbicides by playing a role in oxidative stress tolerance in addition to detoxifying herbicides by catalysing their conjugation with glutathione.

Tackling the emerging pandemic of non-communicable diseases in sub-Saharan Africa: the essential NCD health intervention project

There is evidence that the prevalence of certain non-communicable diseases, such as diabetes and hypertension, is increasing rapidly in parts of sub-Saharan Africa. Others, such as asthma and epilepsy, are known to be common but to be poorly managed. This paper describes a project, funded by the Department for International Development of the British Government, which aims to provide costed and evaluated treatment packages for use at primary health care level, methods and materials for evaluating the quality of non-communicable disease care, and a protocol for the assessment for national opportunities for the prevention of hypertension, heart disease and diabetes. Methods are being developed and piloted in urban and rural Tanzania and Cameroon.

An inverse relation between blood pressure and birth weight among 5 year old children from Soweto, South Africa

STUDY OBJECTIVE

To examine the relation between birth weight and blood pressure at 5 years in a cohort of South African children.

DESIGN

Prospective cohort study.

PARTICIPANTS

849 five year old children.

SETTING

Soweto, a sprawling urban area close to Johannesburg, South Africa, which was a designated residential area for people classified as "black" under apartheid legislation.

MAIN RESULTS

Systolic blood pressure at 5 years was inversely related to birthweight (r = -0.05, p = 0.0007), independent of current weight, height, gestational age, maternal age or socioeconomic status at 5 years. There was no relation between birth weight and diastolic blood pressure. After adjusting for current weight and height, there was a mean decline in systolic blood pressure of 3.4 mm Hg (95% confidence intervals 1.4, 5.3 mm Hg) for every 1000 g increase in birth weight.

CONCLUSIONS

These data from a disadvantaged urbanised community in Southern Africa extend the reported observations of an inverse relation between birth weight and systolic blood pressure. The study adds to the evidence that influences in fetal life and early childhood influence systolic blood pressure. Further research is required to assess whether efforts to reduce the incidence of low birthweight babies will attenuate the prevalence of hypertension in future generations.

A prospective controlled trial of the efficacy of isopropyl alcohol wipes before venesection in surgical patients

It has previously been suggested that skin preparation before venesection with antiseptic agents is unnecessary. However thousands of doctors and medical students continue to use isopropyl alcohol (IPA) swabs for venesection, at an estimated cost of 10,000 P per annum in a 500 bed hospital. An audit of IPA swab use among junior doctors and medical students at our institution was undertaken; 76% of doctors and 100% of medical students routinely prepared the skin with alcohol before venesection and only one used the swabs correctly. A randomised single-blind controlled trial was conducted of IPA versus no IPA skin preparation before venesection. There were 194 patients in the study, 93 in the IPA group and 101 controls. There was no statistical difference with respect to complications at the venepuncture site between the two groups.

Speed-dependent responses in V5: A replication study

In a previous paper, we used fMRI to examine motion-sensitive responses in human area V5 as a function of stimulus speed. As predicted by electrophysiological findings, we observed optimal responses at intermediate speeds of around 7 to 30 degrees /s. These results revealed a nonlinear (inverted "U") dependency on speed that was also evident in V3a. In this paper we repeated the experiment using an improved stimulus and a larger range of speeds. We replicated our previous findings and extended our characterization of speed-dependent responses: Optimal responses were seen in V5 at speeds of 4 and 8 degrees /s and in V3a at speeds of 4 to 16 degrees /s. We were also able to show an interaction between speed (fast vs slow) and contrast (color > luminance) in V5. This interaction was anticipated on the basis of the different properties of the geniculate and extrageniculate inputs to V5. Finally, we were also able to demonstrate an interaction between motion (moving vs stationary) and contrast (color > luminance) in V4. This suggests that for V4, color-specific responses are augmented in the context of motion; or equivalently, that color contrast enhances any motion-sensitive responses in V4.

Quantification of neuromotor function for detection of the effects of manganese

The effect of low level exposure to manganese (Mn) was examined in 297 subjects from southwest Quebec. Blood manganese (MnB) levels as well as other possibly relevant variables were obtained. We tested equipment and analysis procedures that we have developed to quantify aspects of motor function thought to be affected by exposure to toxins, in particular, rapid alternating movements, rapid and precise pointing movements, and tremor. (1) The eurythmokinesimeter measures timing and precision of contacts between a hand-held stylus and a pair of metal targets (proximal/distal). This roughly approximates the finger-to-nose test of the UPDRS. Characteristics quantifying speed, precision and regularity of the movements were calculated, as well as multiple contacts due to tremor and an index based on Fitts' Law eliminating the effect of the trade-off between speed and precision. (2) The diadochokinesimeter accurately measures rapid rotation of the forearms (pronation/supination). Characteristics quantifying the range, speed, period, shape and regularity of the oscillatory movements were calculated, as well as the smoothness of the movement on a fine scale and the coordination between the two hands. (3) Postural tremor of the arm and hand was measured using the accelerometry-based "TREMOR" system of Danish Product Development. We used the amplitude and frequency characteristics provided by the TREMOR system: intensity, center frequency, dispersion and harmonic index. Previous studies have shown that these tests are sufficiently sensitive to detect small differences in performance of different groups of subjects, with indications that some characteristics are also specific to particular conditions. In this study, significant though small effects related to age and gender were found in many of the characteristics. When effects of other variables are removed, low-level exposure to Mn was found to be associated with a decrease in ability to perform regular, rapid and precise pointing movements, a decrease in ability to attain high maximum rotation speeds in rapid alternating movements, and an increase in regularity of tremor oscillations. Moreover, the effects are age-related for levels of MnB 7.5, micrograms/L.

Manganese neurotoxicity, a continuum of dysfunction: results from a community based study

Excessive manganese (Mn) has been associated with neurobehavioral deficits and neurological and/or neuropsychiatric illness, but the level at which this metal can cause adverse neurotoxic effects, particularly with long-term exposure, is still unknown. The objective of the present study was to assess nervous system functions in residents exposed to manganese from a variety of environmental sources. A random stratified sampling procedure was used to select participants; persons with a history of workplace exposure to Mn and other neurotoxic substances were excluded. A self-administered questionnaire provided data on socio-demographic variables. Blood samples were analyzed for total manganese (MnB), lead, mercury and serum iron. Nervous system assessment included computer and hand-administered neurobehavioral tests, computerized neuromotor tests, sensory evaluation and a neurological examination. The present analyses include 273 persons (151 women and 122 men); MnB range: 2.5 micrograms/L-15.9 micrograms/L (median: 7.3 micrograms/L). Multivariate analyses were used and neuro-outcomes were examined with respect to MnB, taking into account potential confounders and covariables. Results were grouped according to neurofunctional areas and MANOVA analyses revealed that higher MnB (7.5 micrograms/L) was significantly associated with changes in coordinated upper limb movements (Wilks' lambda = 0.92; p = 0.04) and poorer learning and recall (men: Wilks' lambda = 0.77; p = 0.002; women: Wilks' lambda = 0.86; p = 0.04). Further analyses revealed that with increasing log MnB (Simple regression: p < 0.05) performance on a pointing task was poorer, frequency dispersion of hand-arm tremor decreased, while harmonic index increased, and the velocity of a pronation/supination arm movement was slower. An Mn-age interaction was observed for certain motor tasks, with the poorest performance observed among those _50 y and in the higher MnB category. Differences between genders suggest that men may be at greater risk than women, although effects were also observed in women. These findings are consistent with the hypothesis that Mn neurotoxicity can be viewed on a continuum of dysfunction, with early, subtle changes at lower exposure levels.

Risk: a media perspective

The joumalist's quest for stories and the media's business needs pose problems for those who work in radiation protection. Accidents are news; routine operations are not. Relations with journalists have been damaged by dishonesty about radiation. Secrecy, a legacy of the atomic bomb, still persists throughout the nuclear industry and distorts public debate. Examples are given. There is also scientific uncertainty about the effects of low-level radiation because of the discoveries being made in Harwell, Dublin and Harvard about genomic instability. The key to how people perceive risks is the degree of control they exert over them. People are not in control of the risks they encounter from radiation. Hence they dislike additions of artificial radioactivity from bomb tests, Chernobyl and Sellafield. This is a sensible response that should be dealt with honestly.

Prevalence and degree of expression of the carbapenemase gene (cfiA) among clinical isolates of Bacteroides fragilis in Nottingham, UK

The carbapenemase gene (cfiA) was detected in 12 (6.9%) out of 175 clinical isolates of Bacteroides fragilis from Nottingham, three times the frequency reported from France. Only one gene copy was present in all cases. Eleven (6.3%) of the cfiA-positive isolates were susceptible to imipenem or meropenem (MIC < 8 mg/L); strains of this type have the potential to convert to high-level resistance. One isolate (0.6%) displayed resistance to both carbapenem antibiotics and was associated with specific carbapenemase activity six times that of the sensitive isolates.