Ethnicity and childhood mortality in The Netherlands

Background: This paper describes the rates and the causes ofdifferences in childhood mortality between Turkish, Moroccanand native Dutch children in The Netherlands. Methods: Retrospectiveanalysis of all routinely collected death certificates of 0–15year old children who died between 1979 and 1993. In total 20,211death certificates of which 1,764 of Turkish and Moroccan childrenwere analysed. Childhood mortality was divided into four ageperiods, analysed according to ICD-9 codes and measured overthree five-year periods. Results: Compared to native Dutch children,the relative mortality risk (RR) for Turkish and Moroccan infantsand children is twice as high. It did diminish from 3.2 in thefirst five- year period (1979–1983) to 2.2 in the second(1984–1988). After 1988 no further decline In relativemortality risk was noticed (RR: 2.1). Minor differences werefound between the Turkish and Moroccan groups in the four differentage categories. The relative risk for Turkish and Moroccan childrento die from different diagnostic categories is as follows: Infectiousdiseases: RR 2.2 (95% Cl: 1.83–2.68), hereditary (metabolic)disorders: RR 2.0 (Cl: 1.78–2.20), accidents en drowningRR 1.9 (Cl: 1.64–2.21). There was a decline In all causespecific mortality ratios over time except for hereditary disordersand (traffic) accidents and drowning. One quarter of the Turkishand Moroccan children died while on holiday in their countryof origin. The only significant difference between the Turkishand Moroccan group was found in Sudden Infant Death Syndrome.While the actual number of SIDS cases declined drastically overthe last five year period, the SIDS rate for Turkish infantsremained twice as high as for Dutch Infants and four times higherthan for Moroccan infants. Conclusion: Differences in mortalitybetween Turkish, Moroccan and Dutch children are significantand have hardly changed during the last 10 years. Apart fromapparent socio-economic differences, socio-cultural and life-stylefactors may play an important role as well. Preventive measuressuch as health and safety education concerning the (yearly)holiday trip to the country of origin, genetic counselling inconsanguinity, better knowledge of early warning symptoms ofserious infectious diseases, road safety education and earlyswimming-lessons are possible. The high SIDS differences haveto be investigated further.     

The Effect of Concentration on the Structure of α-Crystallin

Several models have been proposed for arrangement of the subunits in α-crystallin. These include the contrasting proposals that subunits are arranged in three layers and that subunits assemble into micelle-like structures. The validity of the micelle model was investigated by examining the effects of variations in protein concentration on the surface tension, conductivity, molecular weight and conformation of α-crystallin. The data were compared with those obtained for bovine serum albumin (BSA) and sodium dodecyl sulphate (SDS).Measurements of surface tension were conducted in the range, 10μgml^-1to 130mgml^-1, in low and high ionic strength buffers. An apparent point of inflection, independent of ionic strength, was seen in α-crystallin's surface tension at around 1.9mgml^-1(95μm). The surface tension did not plateau beyond this point, as is the case with surfactants, but continued to decrease up to 130mgml^-1. BSA exhibited similar surface tension properties with an apparent inflection at 0.9mgml^-1(13μm).The conductivity of α-crystallin and BSA solutions increased smoothly with no sign of any transition up to 96mgml^-1and 60mgml^-1, respectively. In contrast, SDS showed a clear transition in this property at the concentration corresponding to its CMC.The aggregation state of the α-crystallin aggregates was examined by comparing molecular masses and Stokes radii. The size of the protein remained uniform over a wide concentration range and was unaffected by variations in ionic strength. Protein conformation, which was monitored by examining the microenvironment of tryptophan residues, was also found to be independent of protein concentration.It is concluded that over the concentration range that was investigated, α-crystallin does not exhibit any of the properties associated with classical micelles formed from small amphiphilic molecules.     

Brief Note: Hemoglobin J in a Healthy Hawaiian-Chinese-Caucasian Male

Hemoglobin J is reported in a 27 year old healthy adult Hawaiian-Chinese-Caucasian male and 3 of his offspring. All were healthy and displayed nohematologic disturbances except for the Youngest offspring, who exhibitedmild nutritional iron deficiency anemia.

Submitted on July 22, 1959 Accepted on October 23, 1959     

F8 gene dosage defects in atypical patients with severe haemophilia A

Summary. We performed molecular analysis of the factor 8 gene (F8) in 272 unrelated Spanish patients with haemophilia A (HA) and detected a mutation by routine analysis in 267 of them (98.1%). No mutation was detected in the remaining five patients despite clinical and laboratory confirmation of HA. The aim is to describe the molecular alterations in F8 discovered by gene dosage methodologies in three of these patients. For methodology, F8 sequencing, intragenic marker analysis, multiplex ligation-dependent probe amplification and quantitative real time-PCR were followed. One patient had Klinefelter syndrome (47,XXY) and a large deletion spanning exons 1-12 masked by the other F8 allele; the second patient showed a large duplication spanning exons 2-10 and the third patient revealed a non-contiguous double duplication of exons 14 and 23-25. The remaining two patients had mild HA and dosage results were normal. The application of gene dosage methods is useful to define haemophilic patients in whom mutations are not detected using other routine methods. Nevertheless, in a small percentage of patients (<1%), no molecular pathology can be identified after testing several genetic methodologies.     

The Subpectoral Pocket: The Preferred Implant Site for Pediatric Pacemakers

Implantation technique for pediatric pacemaking has evolved from predominantly epicardial to predominantly endocardial. One of the potential problems with endocardial pacing in children is their very thin subcutaneous tissue, which can result in an unpleasant cosmetic result. The superficialness of the pacemaker pulse generator also may render it more susceptible to erosion and infection. A series is presented of pediatric patients who underwent implantation of a transvenous bipolar pacing system in the pediatric catheterization laboratory. The pacemaker was implanted under the pectoralis major muscle after a muscle spreading incision was made. The lead was also introduced into the subclavian vein under the pectoralis muscle. No complications resulted, and the cosmetic result was judged to be good to excellent by the parents and physicians. No infections or erosions occurred. The subpectoral pocket is recommended as the preferred site for implantation of transvenous pacemakers in pediatric patients.