Neonatal weight loss in breast and formula fed infants

OBJECTIVE: To define the range of neonatal weight loss in a population relative to feeding method. DESIGN: Prospective observational cohort study. SETTING: Maternity service providing geographically defined, community based newborn follow up. PARTICIPANTS: 971 consecutive term newborns of birth weight > or = 2500 g during the first 2-3 weeks of life; 34 excluded (inadequate data). 937 included: 45% breast fed, 42% formula fed, 13% breast and formula fed. OUTCOME MEASURES: Maximum weight loss and timing, age on regaining birth weight. RESULTS: Median weight loss: formula fed 3.5%, breast fed 6.6%. Upper centiles for maximum weight loss differ considerably (95th centiles: breast fed = 11.8%, formula fed = 8.4%; 97.5th centiles: breast fed = 12.8%, formula fed = 9.5%). Median time of maximum weight loss: 2.7 days for breast fed and formula fed. Recovery of birth weight: breast fed median 8.3 days, 95th centile 18.7 days, 97.5th centile 21.0 days; formula fed median 6.5 days, 95th centile 14.5 days, 97.5th centile 16.7 days. The time taken to regain birth weight correlates with both the degree and timing of initial weight loss for all groups. CONCLUSIONS: Early neonatal weight loss is defined allowing identification of infants who merit closer assessment and support.     

Leukocyte coping capacity: a novel technique for measuring the stress response in vertebrates

Methods used to quantify the stress response in animals are vital tools in many areas of biology. Here we describe a new method of measuring the stress response, which provides rapid results and can be used in the field or laboratory. After a stressful event, we measure the capacity of circulating leukocytes to produce a respiratory burst in vitro in response to challenge by phorbol myristate acetate (PMA). During the respiratory burst leukocytes produce oxygen free radicals, and the level of production can be measured directly as chemiluminescence. When in vitro PMA-stimulated whole blood chemiluminescence is measured directly after a stressful event, we define the response as the leukocyte coping capacity (LCC). In an experiment badgers (Meles meles), which were caught as part of an on-going population study, were either transported to a central site prior to blood sampling or blood was collected at their site of capture. Transported animals had a significantly lower LCC and showed changes in leukocyte composition that were indicative of stress. We conclude that the stress of transport reduced LCC in badgers and that LCC serves as a quantitative measure of stress. Potential applications of this method are discussed.     

The recognition of dementia in "non-EMI" nursing home residents in South East England

OBJECTIVES: To estimate the agreement between nursing staff's recognition of dementia and results of MMSE assessment in a probability sample of non-specialist nursing home residents in South East England, and to identify correlates of disagreement. METHODS: Prospective survey. The most senior nurse on duty was interviewed about each resident sampled, and optionally about their own training and experience. Residents were interviewed using the MMSE, and assessed using the Cornell Scale for Depression in Dementia, the Barthel ADL index, and the Behave-AD scale for behavioural problems. RESULTS: 135 nurses were interviewed about 445 residents-116 reported on of the 291 residents scoring 23 or less on the MMSE-34% of these were acknowledged to have dementia. 46.4% of those with MMSE scores of 15 or less were acknowledged to have dementia. "Missed dementia" was associated with higher MMSE and lower Behave-AD scores, and inversely associated with RMN training and private home ownership for profit. It was not associated with training or duration of staff employment. CONCLUSIONS: Most cognitive impairment in non-specialist nursing homes appeared to be unrecognised. This has implications for the prospects of good dementia care in these homes.     

The mouse Chrna4 A529T polymorphism alters the ratio of high to low affinity alpha 4 beta 2 nAChRs

Previously, a missense polymorphism was identified in the mouse nicotinic receptor alpha4 subunit gene, Chrna4. This polymorphism leads to an Ala/Thr variation at amino acid position 529 of the alpha4 subunit. Chrna4 A529T is associated with several measures of acute sensitivity to nicotine as well as with mouse strain differences in nicotine-stimulated (86)Rb(+) efflux from synaptosomes. Here, we report that the variant forms of the mouse alpha4 subunit confer functional differences when expressed with the beta2 subunit in a heterologous system. alpha4beta2 receptors containing the T529 variant of the alpha4 subunit exhibited a higher EC(50) value for the high affinity receptor population and an apparent reduced sensitivity to blockade by DHbetaE relative to alpha4beta2 receptors containing the A529 variant of the alpha4 subunit. Moreover, the proportion of the total agonist-elicited current contributed by the high affinity alpha4beta2 receptor population was greater for alpha4beta2 receptors containing the alpha4(T529) variant (64%) than the alpha4beta2 receptors containing the alpha4(A529) variant (41%). These data suggest that the polymorphism in the mouse alpha4 subunit is located in a previously unidentified functional domain of the receptor subunit that influences receptor function, including regulation of the affinity population ratio of alpha4beta2 receptors.     

Secondary thrombocytosis

To estimate the incidence and causes of secondary thrombocytosis in children, a 12 month study of all patients attending a children's hospital and discovered to have a platelet count over two times the upper normal limit (> 800 x 10(9)/l) was undertaken. Data so obtained were analysed both separately and together with those from two previous studies to gain as broad a perspective as possible. Of 7916 children who had platelet counts during the study period, 36 (0.5%) produced a value > 800 x 10(9)/l; there were 19 boys and 17 girls. There was a preponderance of young infants (median age 13 months). Twenty seven of the 36 had some sort of associated infection, bacterial in 18 and viral in nine. The other nine were either recovering from anti-neoplastic chemotherapy (n = 6), were post-operative (n = 2), or simply iron deficient (n = 1). Combining these patients with those described in previous studies allowed a review of 139 unselected children with very high platelet counts. Fifty three (38%) had infections, 29 (20%) had traumatic or surgical tissue damage, 16 (11%) had malignant disease undergoing chemotherapy or surgery, and 13 (9%) had connective tissue or autoimmune disorders. Secondary thrombocytosis is not rare and is most frequently seen in very young infants after infection. It can arise in a wide variety of other circumstances including rebound from myelosuppression, iron lack, or as part of an acute phase response. It is clinically unimportant in terms of morbidity and requires no treatment other than that for the primary condition.     

Congenital thiopurine methyltransferase deficiency and 6-mercaptopurine toxicity during treatment for acute lymphoblastic leukaemia

Two children with acute lymphoblastic leukaemia (ALL) taking daily 6-mercaptopurine as part of a national UK therapeutic trial repeatedly developed profound myelosuppression on 25% of the standard protocol dose. Both were found to have undetectable intracellular activity of thiopurine methyltransferase (TPMT), an enzyme controlling one of the major alternative catabolic pathways of 6-mercaptopurine, and both produced higher concentrations of cytotoxic drug metabolites at 10-25% of the protocol dose than other patients taking 100%. It is supposed that these patients represent the 0.33% of the normal population constitutionally lacking TPMT. It is important to recognise such individuals both to avoid fatal bone marrow failure through inadvertent overdosage, and to be reassured that an adequate drug effect can be achieved at around 10% of the standard dose.