What do dentists know about statistics?

Abstract – A multiple choice test with nine statistical questions was sent to a random sample of Danish dentists to assess their knowledge of elementary statistical expressions (SD, SE, P<0.05, P> 0.05 and r). Of 250 dentists, 129 (52%) answered the questions. The test was also completed by 27 (71%) of 38 dental students immediately after the last lecture in statistics. The median number of correct answers was 2.2 among the dentists and 3.4 among the dental students. It is concluded that the statistical knowledge of most dentists, and to a lesser degree also dental students, is so limited that they cannot be expected to be critically against or to draw the right conclusions from those statistical analyses with which they are confronted. Only 35% of the dentists stated that it is very important that this problem be raised.     

Defective Monocyte Function in Legionnaires' Disease Complicating Hairy Cell Leukaemia

ABSTRACT We describe a case of Legionnaires' disease in a 64-year-old man, in which hairy cell leukaemia was diagnosed after the onset of the infection. Immunological studies revealed a complete suppression of blood monocyte chemotactic and oxidative burst activities. We suggest that in hairy cell leukaemia both monocytopenia and defective functions of monocytes underlie the increased susceptibility to intracellular infections including Legionnaires' disease.     

Improvements in automated PNA synthesis using Boc/Z monomers

An optimized automated PNA synthesis protocol is reported. Under optimal conditions the product yield of a test 17-mer PNA is approximately 90%. The average coupling yield is 99.4%. The synthesis strategy is Boc/Z and the deprotected amine is neutralized in situ. The monomers are added in molar excess to HATU and pre-activated for 60 s before delivery to the resin. The concentration of the activated monomers is 0.08 m during the couplings. Heteroselective solvation provides the highest coupling yields. Acetic anhydride is used as capping reagent followed by a piperidine wash. The protocol has been developed in a 5 μmol scale but is easily scaled up to 10–50 μmol scale syntheses on the automated synthesizer (ABI 433A). © Munksgaard 1997.     

Effect of anticoagulation upon nephron obstruction in experimental acute ischaemic renal failure. A morphological study

Ischaemic-reperfusion injury as a model of acute renal failure (ARF) results in increased macromolecular permeability, tubular obstruction, and renal oedema. To investigate the role for coagulation in this model, anticoagulated and saline-pretreated rats were subjected to 60 min unilateral renal artery occlusion (RAO). After 15 min of reflow, specimens were collected for electron and light microscopic examination. Morphometry was employed to study podocyte changes and Bowman's space dilatation as measures of increased permeability and tubular obstruction, respectively. After 15 min of reflow, Bowman's space increased significantly and the podocytes were markedly widened and flattened. Rats pretreated with heparin or warfarin showed less widening of Bowman's space than saline-treated rats, whereas no significant difference was seen regarding the podocyte changes. In saline-treated rats, fibrin-positive material was seen in the tubules but not in the urine sediments collected after 90 min of reflow, either due to fibrinolysis or poor urinary elimination. The results suggest that anticoagulation does not preclude the glomerular sieving of macromolecules, but seems to reduce tubular obstruction, probably by preventing conversion of filtered fibrinogen into fibrin.     

Long-Term Follow-Up of Patients Treated with Automatic Scanning Antitachycardia Pacemaker

The long-term efficacy of an automatic antitachycardia pacemaker was evaluated in 13 patients with supraventricular tachycardia and in two patients with ventricular tachycardia. Patients were followed for 4–53 months (median 16). The concertina scanning mode with 2–7 extrastimuli proved to be effective in all patients but one. During follow-up, two patients had to be reoperated due to sensing problems. Atrial flutter was induced during scanning in one patient, termination mode was triggered by sinus tachycardia in one patient despite beta blocker therapy, and in one patient after cessation of beta blocker treatment. The pacemaker did not induce any serious arrhythmias and no sudden deaths occurred. Seven patients were given beta blockers, one patient with ventricular tachycardia was additionally administered amiodarone. In conclusion, the PASAR 4171 (Telectronics, Englewood, CO, USA) automatic scanning pacemaker is an alternative or adjunctive means to chronic antiarrhythmic drug therapy in patients with supraventricular tachycardia, but further versatility with regard to sensitivity, refractory period, and tachycardia recognition is required to eliminate the shortcomings observed, including the need for additional beta blocker therapy.     

Faecal Concentrations and Production Rates of Short Chain Fatty Acids in Normal Neonates

ABSTRACT. Changes in intestinal microbial flora are reflected in the faecal concentrations and production rates of short chain fatty acids. However, since no data on the latter are available in neonates, the aim of this study is to provide information on short chain fatty acids in faeces from normal neonates. Faecal samples were collected immediately after birth (meconium) and on the 4th day of life in 13 healthy, full-term neonates. The production capacity was evaluated by a faecal incubation system. Concentrations of short chain fatty acids were low in meconium (11.2+3.9 mmol/l (mean±SD)), equivalent to about 10% of the adult level ( p <0.01), but increased significantly during the first 4 days of life to 28.4±20.1 mmol/l ( p <0.05). The fermentation pattern (i.e. relative composition of different acids) showed differences between adults and neonates, primarily due to a higher proportion of acetate found in the latter. The ratio acetate/propionate/butyrate/other acids was 89/5/5/1 in 4-day-old neonates compared to 65/18/11/6 in adults ( p <0.001). Our findings correlate well with the postnatal microbial colonization of neonatal colon.     

Effect and stage models in community intervention programmes; and the development of the Model for Management of Intervention Programme Preparation (MMIPP)

Recent years have seen the development of a number of diagrammatic‘models’ bearing on community intervention programmes.There have been two basic types, one involving actual or hypotheticalcausal relationships (effect, or how-it-works models) and theother, sequences of activities or events (stage, or how-to-do-itmodels). A selection of such models, with their roots in differenttheories of social change, health education and health promotion,are reviewed in the light of this distinction. Both types ofmodel are important. Existing stage models for health promotion programmes implyan ordered or cyclical set of activities, in which preparationis followed by implementation, maintenance, evaluation and revision.In the second part of the paper a new and more detailed typeof stage model is presented for the preparatory phase. In practice,this phase involves a series of parallel but interdependentactivity streams. These add up to a complex process that needsto be carefully planned and managed. In such circumstances itis important to be able to convey to the various people andorganisations involved how their different contributions meshtogether. The new model is designed to help with this. It hasbeen developed in the light of experience of planning community-baseddisease prevention programmes in Stockholm and elsewhere, withthe objective of making the lessons learned available for othersin a compact and accessible form.     

GLUCOCORTICOID MAINTENANCE THERAPY FOLLOWING ADRENALECTOMY: ASSESSMENT OF DOSAGE AND PREPARATION

Plasma cortisol was monitored repeatedly after oral administration of cortisol and cortisone (cortisone acetate) to seven adrenalectomized patients with pituitary-dependent Cushing's syndrome. The amount of glucocorticoid administered was 25 mg cortisol or 33 mg cortisone/g urine creatinine/24 h. Peak plasma cortisol levels were within recommended values in all patients after cortisone and in three of the patients after cortisol. The remaining four patients had elevated peak plasma cortisol levels after cortisol. Transcortin binding capacity in plasma was normal. It is concluded that cortisol as well as cortisone is suitable for oral glucocorticoid substitution therapy in patients with normal liver function, but that cortisone apparently gives a marginally smoother plasma cortisol curve. However, it is essential to monitor plasma cortisol after institution of glucocorticoid maintenance therapy, since different and unpredictable plasma cortisol levels may exist after a given amount of glucocorticoid, although the dose required correlates reasonably well with creatinine excretion in urine.