SAPALDIA: methods and participation in the cross-sectional part of the Swiss Study on Air Pollution and Lung Diseases in Adults

SAPALDIA--the Swiss Study on Air Pollution and Lung Diseases in Adults--focuses on the long term health effects of low to moderate levels of air pollutants as typically seen in different parts of Switzerland. The aim of the SAPALDIA cross-sectional study carried out in 1991 was to determine the prevalence of bronchial asthma, chronic bronchitis and allergic conditions in the adult population of Switzerland and to identify and to determine the respective importance of potentially influencing factors. These could be both personal (smoking habits, allergy status, family history, occupation) and environmental (outdoor and indoor pollution, aeroallergens, climate). A further aim of the cross-sectional study consisted in the identification of individuals susceptible to present symptoms during a two year observation period and to be included in the SAPALDIA follow-up study. This technical report represents the methodological documentation for the cross-sectional study of SAPALDIA. The instruments and the methods of standardisation are presented and discussed. The medical examination consisted of a computerised interview using a standardised questionnaire, the taking of a blood sample for serological tests, allergy skin testing, the measurement of end expiratory CO and body height, and pulmonary function testing followed by methacholine challenge testing or bronchodilatation testing. The pattern of participation and the 9651 participants of the study, representing 59.3% of the sample, are described. Based on information on non-participants gained by telephone interviews and mailed short questionnaires, possible selection biases are quantified and discussed.     

Calcium and vitamin D status of pregnant teenagers in Maiduguri, Nigeria

This study investigates parameters related to calcium and bone metabolism by determining the concentrations of total calcium, 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, parathyroid hormone, and phosphorous in young pregnant women. The patient population was 30 pregnant Nigerian teenage women grouped by trimester (10 per group), 10 women immediately following delivery, and 21 healthy age-matched controls. On the basis of serum prealbumin levels, the general nutrition of the pregnant women was found to be significantly below that of the more privileged and better-educated nonpregnant controls. The mean total calcium concentration in sera of the third-trimester women was 8.83 mg/dL, which was significantly below that of the controls (9.77 mg/dL) and the first-trimester group (9.30 mg/dL). Despite the 10% to 15% decline in the serum level of total calcium during pregnancy, the parathyroid hormone level decreased markedly from 0.60 to 0.61 ng/mL in the first and second trimesters to 0.41 ng/mL in the third trimester. Serum vitamin D and 1,25-dihydroxyvitamin D levels in the second and third trimesters were within the normal range. These data indicate that toward the end of gestation, pregnant teenagers in northern Nigeria appear to become calcium deficient and do not exhibit the expected increase in serum parathyroid hormone levels normally seen in pregnant women.     

Actin disassembles reversibly during electrically induced recycling of synaptic vesicles in cultured neurons

We have studied depolarization-induced regulation of actin assembly in exocytotically active areas of dissociated chick sympathetic neurons. Active areas were identified with the fluorescent dye FM1-43 which labels synaptic vesicles that recycle in these regions. Exocytosis (electrically stimulated) was monitored in real time through depletion of FM1-43 fluorescence. To study depolarization-induced disassembly of actin in the FM1-43-stained regions, the cells were fixed after different periods of depolarization and stained with rhodamine phalloidin, which binds preferentially to the filamentous form of actin. In active regions, actin disassembles and reassembles during continuous 2 min depolarization. Actin disassembly that occurs after the first 25 s of depolarization was detected by a reduction in rhodamine phalloidin staining and confirmed by correlative electron microscopy. Immunogold staining revealed that actin is abundant throughout resting terminals. In some experiments, actin filaments were stabilized by loading cells with unlabelled phalloidin before stimulating secretion. Stabilizing the filaments does not alter the initial release but strongly reduces the release rate at later stages. These data are consistent with a model in which partial disassembly of actin filaments is necessary for facilitating the transport of vesicles within the terminal and reassembly is necessary for limiting that movement.     

Membrane lipids of Rhodopseudomonas viridis

In search of the precyanobacterial origin of the typical thylakoid lipids found in cyanobacteria and chloroplasts, we analyzed the polar lipids of the anaerobic phototrophic bacterium Rhodopseudomonas viridis. Glycolipids (monogalactosyl-, digalactosyl- and glucuronosyl diacylglycerol), phospholipids (phosphatidyl choline, -ethanolamine, -glycerol and cardiolipin) and an ornithine lipid were isolated and identified by NMR (1H, 13C, 31P) and mass spectrometry. Positional distribution and pairing of fatty acids in molecular species show small, but significant differences between glyco- and phospholipids. In this context, a new enzymatic method is described for assigning the enantiomeric structure of the diacylglycerol moiety in glyco- and phospholipids. 14C-Labelling studies suggest that monogalactosyl diacylglycerol is formed by galactosylation of diacylglycerol as in chloroplasts and not by glucosylation followed by epimerization as in cyanobacteria. The two 1,6-linked galactopyranose residues of digalactosyl diacylglycerol are both in beta-linkage and thus differ from the corresponding chloroplast lipid with its alpha-beta-sequence. R. viridis does not contain the sulfolipid, and even phosphate starvation does not induce the synthesis of this most characteristic thylakoid lipid, which on the other hand is present in other anaerobic phototrophic bacteria.     

The results of radiotherapy for ependymomas: the Mayo Clinic experience

It is known that exogenous 11-cis-retinol inhibits the recovery of photosensitivity of bleached rod outer segments (ROS) and 11-cis-retinol exists in the interphotorecepter matrix. We examined the conversion of 11-cis-retinol with bovine ROS. ROS was incubated with 11-cis-retinol under dim red light. Retinoids were extracted from the reaction mixture with hexane and analyzed by HPLC coupled with a fluorescence spectrophotometer. Isomerization of 11-cis-retinol to all-trans-retinol was observed in the presence of ROS. This isomerization was not suppressed by heat treatment and did not have stereospecificity. In addition, we incubated purified rhodopsin and phospholipids extracted from ROS with 11-cis-retinol. Rhodopsin was found to isomerize 11-cis-retinol to all-trans-retinol as well as ROS, but phospholipids did not. In contrast, the phospholipids inhibited the isomerization of 11-cis-retinol to all-trans-retinol by the purified rhodopsin. Commercially available phospholipids, especially phosphatidylserine, also inhibited the isomerization. Our results suggest that rhodopsin has activity for the isomerization of 11-cis-retinol to all-trans-retinol and may play an important role in the detoxification of 11-cis-retinol in the ROS.     

Spermine-mediated phosphorylation of RNA polymerase I and its effect on transcription

A nuclear protein kinase, designated NII, was purified essentially to homogeneity from the Morris hepatoma 3924A. In the presence of excess Mg2+, phosphorylation of casein by the kinase was stimulated by spermine (1-5 mM) and was inhibited completely by 0.1 microgram/ml heparin. The apparent Km for casein was reduced in the presence of spermine. Spermine preferentially augmented phosphorylation of threonine residues. The kinase was also associated with highly purified RNA polymerase I and appears to correspond to two polypeptides (Mr 42,000 and 24,600) of the polymerase. RNA polymerase I polypeptides of Mr 120,000 (S2), Mr 65,000 (S3) and Mr 24,600 (S5) were phosphorylated by the endogenous kinase. Spermine enhanced phosphorylation of the RNA polymerase I subunits as much as 20-fold. Phosphorylation activated RNA polymerase I; the phosphorylated enzyme synthesized longer product with no apparent effect on the number of RNA chains initiated.     

Presentation, treatment, and outcome of local recurrence afterskin-sparing mastectomy and immediate breast reconstruction

To evaluate the relative role of plasma and platelet von Willebrand factor (vWF) pools in hemostasis and arterial thrombogenesis, pigs with vW disease (vWD) were injected with vWF concentrate and/or grafted with bone marrow from a normal pig. Hemostasis was assessed by measurement of ear immersion bleeding time, factor VIII (FVIII) activity, and plasma and platelet vWF antigen levels. The thrombotic process was explored at 650 s(-1) and 1600 s(-1) in an ex vivo cylindrical perfusion chamber. Pigs with vWD exhibited a prolonged bleeding time (>30 minutes) compared with normal pigs (<5 minutes); in addition, they showed normal platelet adhesion and thrombus formation at 650 s(-1) but profoundly reduced platelet adhesion and thrombus formation at 1600 s(-1). Each experiment was performed before and 3 and 24 hours after injection of vWF concentrate. In our bleeding time study, only plasma vWF restoration induced a partial but delayed correction (24 hours postinjection), which was correlated with the highest measured level of FVIII activity. In the perfusion chamber model, restoration of plasma or platelet vWF pools resulted in similar partial correction of platelet adhesion and average thrombus size. In the perfused pigs, the maximum correction occurred 3 hours postinjection. Platelet deposition reached normal values after vWF concentrate was injected into a grafted pig. The present results suggest that when both plasma and platelet vWF levels are restored in vWD pigs, bleeding time and the thrombotic process are normalized according to different kinetics and with differing degrees of effectiveness.