Interdisciplinary teaching of community paediatrics

An experiment of combining decentralized and interdisciplinary teaching is described. Seminars were arranged at a district hospital for medical, nursing and social work students to discuss families with a chronically ill child. The purpose of these seminars was to teach co-operation between different health care workers, and to stress the importance of becoming acquainted with the family situation, and learn what a child's illness means to the whole family.
An evaluation of the first three seminars shows that this type of teaching was very well received by the students, professionals and families concerned. The students considered house calls an important part of their education and felt that more interdisciplinary teaching should be included in their curriculum. In addition to the teaching aspect, the families involved also considered the seminars a positive experience as they received more information about their child's disease, and deficiencies in treatment could be corrected.     

The Safety of Reusing Ablation Catheters with Temperature Control and the Need for a Validation Protocol and Guidelines for Reprocessing

The objective of this study was to evaluate the safety of reusing ablation catheters with temperature control, which has not previously been reported. A review of previously conducted studies on the feasibility of reusing electrode catheters is also presented. From September 1994 to December 1997, 74 deflectable ablation catheters with temperature control (Cordis-Websters and Osypkas) were used during mean 7.6 ± 8.0 ablation sessions. The catheter tests included visual inspection for surface defects using a magnification glass, impedance measurements, evaluation of the catheter deflection capability, and the integrity of the thermistor and thermocouple. The catheters were sterilized by Sterrad(tm) after each use. A total of 41 catheters were rejected after an average 9.1 ± 8.8 uses (range 1–31). The main reasons for rejection were inaccurate temperature measurements by the thermistor or thermocouple (19 %), breakage of or defect in the internal pulling wire (12%), loss or disturbance of electrogram (9%), and loss of deflection capability (8%). The reuse of the catheters has not resulted in any major catheter failures or any major adverse clinical complications. There were no local or systemic infections. It can be concluded that these types of ablation catheters will sustain repeated uses and resterilizations without untoward harm to the patient provided that a thorough validation protocol and guidelines for quality control and rejection of catheters are used. There seems to be no rational for setting a limit for the number of reuses, since most failures occurred at any time of reuse.     

Asymptomatic Brugada Syndrome Case Unmasked During Dimenhydrinate Infusion

Typical ECG of that described for Brugada syndrome was elicited in a patient diagnosed with labyrinthopathy during infusion of dimenhydrinate, a first-generation antihistamine usually used to treat motion sickness. Although the patient had no history of syncope or palpitations, and there was no family history of cardiac disease or sudden death, the ECG abnormality was reproduced later with intravenous flecainide, and an asymptomatic Brugada syndrome was diagnosed.     

Isolation and characterization of a trisulfide variant of recombinant human growth hormone formed during expression in Escherichia coli

A new variant of human growth hormone was recently found [Pavlu, B. & Gellerfors, P. (1993) Bioseparation 3, 257-265]. We report here the identification and the structural determination of this variant. The variant, which is formed during the expression of human growth hormone in Escherichia coli, was found to be more hydrophobic than rhGH as judged by its prolonged elution time by hydrophobic interaction chromatography. The rhGH hydrophobic variant (rhGH-HV) was isolated and subjected to trypsin digestion and RP-HPLC analysis, resulting in an altered retention time of one single tryptic peptide as compared to the corresponding fragment of rhGH. This tryptic peptide constitutes the C-terminus (aa 179-191) of hGH and contains one of the two disulfide bridges in hGH, viz. CySl82-Cys189. Amino acid sequences and composition analyses of the tryptic peptide from rhGH-HV (T^v_{18 + 19}) and the corresponding tryptic peptide from rhGH (T_{18 + 19}) were identical. Electrospray mass spectrometry (ES/MS) of T^v_{18 + 19} isolated from rhGH-HV revealed a monoisotopic mass increase of 32.7, as compared to T_{18 + 19} from rhGH. A synthetic T_{18 + 19} peptide having a trisulfide bridge between Cys182 and Cys189 showed identical fragments in ES/MS compared to T^v_{18 + 19} isolated from rhGH-HV, i.e. m/z 617.7 and 682.9. These fragments are formed through a unique cleavage in the trisulfide (Cysl82-SSS-Cys189) bridge not found in the corresponding T_{18 + 19} disulfide peptide. Furthermore, the synthetic T^v_{18 + 19} co-eluted in RP-HPLC with T_{18 + 19} isolated from rhGH-HV. Two-dimensional NMR spectroscopy of the synthetic T_{18 + 19} and T^v_{18 + 19} peptides were performed. Using these data all protons were assigned. The major chemical shift changes (δ§>0.05 ppm) observed were for the β-protons of Cys182 and Cys189 in T^v_{18 + 19} as compared to T_{18 + 19}. CD spectroscopy data were also in agreement with the above results. Based on these physico-chemical data, rhGH-HV has been structurally defined as a trisulfide variant of rhGH. The receptor binding properties of rhGH-HV was studied by a biosensor device, BIAcore^TM. The binding capacity of rhGH-HV was similar to rhGH with a binding stoichiometry to the rhGHBP of 1:1.6 and 1:1.5, respectively, indicating that the trisulfide modification did not affect its receptor binding properties. © Munksgaard 1996.     

Genome‐wide linkage of obstructive sleep apnoea and high‐density lipoprotein cholesterol in a Filipino family: bivariate linkage analysis of obstructive sleep apnoea

Increasing evidence supports an association between obstructive sleep apnoea (OSA) and metabolic syndrome (MeS) in both children and adults, suggesting a genetic component. However, the genetic relationship between the diseases remains unclear. We performed a bivariate linkage scan on a single Filipino family with a high prevalence of OSA and MeS to explore the genetic pathways underlying these diseases. A large rural family (n = 50, 50% adults) underwent a 10‐cM genome‐wide scan. Fasting blood was used to measure insulin, triglycerides, total cholesterol and high density lipoprotein (HDL) cholesterol. Attended overnight polysomnography was used to quantify the respiratory disturbance index (RDI), a measure of sleep apnoea. Body mass index z‐scores and insulin resistance scores were calculated. Bivariate multipoint linkage analyses were performed on RDI and MeS components. OSA prevalence was 46% (n = 23; nine adults, 14 children) in our participants. MeS phenotype was present in 40% of adults (n = 10) and 48% of children (n = 12). Linkage peaks with a logarithm of odds (LOD) score >3 were demonstrated on chromosome 19q13.4 (LOD = 3.04) for the trait pair RDI and HDL cholesterol. Candidate genes identified in this region include the killer cell immunoglobulin‐like receptor genes. These genes are associated with modulating inflammatory responses in reaction to cellular stress and initiation of atherosclerotic plaque formation. We have identified a novel locus for genetic links between RDI and lipid factors associated with MeS in a chromosomal region containing genes associated with inflammatory responses.