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The authors are indebted to the collaborators in the participating centres and all parents, children, teachers and other school staff who participated in the surveys. There are many field workers and funding agencies who supported data collection and national, regional and international meetings, including the meetings of the ISAAC Steering Committee. Unfortunately, these are too numerous to mention (they are acknowledged elsewhere) but the authors particularly wish to thank the funders who supported the ISAAC International Data Centre including the Health Research Council of New Zealand, the Asthma and Respiratory Foundation of New Zealand, the National Child Health Research Foundation, the Hawke’s Bay Medical Research Foundation, the Waikato Medical Research Foundation, Glaxo Wellcome New Zealand and Astra New Zealand, as well as Glaxo Wellcome International Medical Affairs for finding the regional coordinating centres. The International Data Centre is now supported by a grant from the BUPA Foundation., The International Study of Asthma and Allergies in Childhood (ISAAC) Phase One showed large worldwide variations in the prevalence of symptoms of asthma, rhinoconjunctivitis and eczema, up to 10 to 20 fold between countries. Ecological analyses were undertaken with ISAAC Phase One data to explore factors that may have contributed to these variations, and are summarised and reviewed here. In ISAAC Phase One the prevalence of symptoms in the past 12 months of asthma, rhinoconjunctivitis and eczema were estimated from studies in 463,801 children aged 13 - 14 years in 155 centres in 56 countries, and in 257,800 children aged 6-7 years in 91 centres in 38 countries. Ecological analyses were undertaken between symptom prevalence and the following: Gross National Product per capita (GNP), food intake, immunisation rates, tuberculosis notifications, climatic factors, tobacco consumption, pollen, antibiotic sales, paracetamol sales, and outdoor air pollution. Symptom prevalence of all three conditions was positively associated with GNP, trans fatty acids, paracetamol, and women smoking, and inversely associated with food of plant origin, pollen, immunisations, tuberculosis notifications, air pollution, and men smoking. The magnitude of these associations was small, but consistent in direction between conditions. There were mixed associations of climate and antibiotic sales with symptom prevalence. The potential causality of these associations warrant further investigation. Factors which prevent the development of these conditions, or where there is an absence of a positive correlation at a population level may be as important from the policy viewpoint as a focus on the positive risk factors. Interventions based on small associations may have the potential for a large public health benefit., peer-reviewed

To report on the prevalence of allergic rhinitis and atopic eczema in school children in Beirut, Lebanon, and compare the prevalence rates of allergic diseases in Beirut to the rest of the world.A random sample of school children aged 13-14 years completed the ISAAC written and video questionnaires. Data was entered using a special program prepared by ISAAC and analyzed using SPSS version 6.0.The prevalence rates of allergic rhinitis and rhinoconjunctivitis were 25.5% and 15.9% respectively. Atopic eczema was more common among males, with a total prevalence rate of 11%.The prevalence rates of allergic diseases in childhood was along the 50th percentile worldwide. The prevalence rates of uncontrolled asthma was very high while that of allergic rhinitis was low as compared to the rest of the world.

Leukotriene B4 (LTB4) from vascular endothelium may play a key role in the genesis of atherosclerotic lesions. However, the ability of this tissue to synthesize LTB4 is controversial. To resolve this issue arachidonic acid metabolism was characterized in cultures of confluent monolayers of a rabbit aortic endothelial cell line by use of both high-pressure liquid chromatography and radioimmunoassay. Cells were grown to confluence in Dulbecco's modified Eagle's medium/Ham's F12 with 5% fetal bovine serum. Lipoxygenase activity was studied by placing the cells in Hank's balanced salt solution with 2 mumol/L indomethacin. After 30 minutes preincubation with indomethacin cells were exposed to either arachidonic acid (10 mumol/L) or arachidonic acid labeled with radioactive carbon (14C) (1 microCi; SA 58 mCi/mmol) and then stimulated with 9.5 mumol/L calcium ionophore A23187 for 55 minutes. Studies of the cyclooxygenase activity were performed without preincubating with indomethacin. Samples were prepared for high-pressure liquid chromatography by evaporation to dryness under a vacuum and resuspending in 2 ml of 1:1 methanol/water. Tritium-labeled standards were added before loading the 14C-labeled samples on the column. Radiolabeled arachidonic acid metabolites were separated by high-pressure liquid chromatography and detected by means of a dual channel flow-through radiodetector that monitors both 14C and 3H. Based on coelution with authentic standards three lipoxygenase metabolites of arachidonic acid have been identified: LTB4, 12- and 5-hydroxyeicosatetraneoic acid. Leukotriene B4 was further characterized by ultraviolet spectral analysis and inhibition studies with use of nordihydroguaiaretic acid. Quantitation was facilitated by commercially available radioimmunoassay kits. An average of 600 pg LTB4/10(6) cells was measured from separate experiments.(ABSTRACT TRUNCATED AT 250 WORDS)

The oxidizing powers of dichromate and ceric sulphate are investigated with various catalysts. The study includes 32 pure organic compounds of various chemical structures. The highest possible oxidation yield is obtained with dichromate in the presence of silver sulphate as a catalyst. Oxidation by ceric sulphate is considerably enhanced by using chromium catalyst. However, certain organic compounds undergo oxidation only in the presence of a double catalyst, namely, Cr plus Ag. Silver and chromium tend to enhance ceric reactions prominently with compounds such as o-cersol, o-toluidine, acetylacetone, acetic acid, lactic acid, succinic acid, and alanine.

SUMMARY Growth obtained from pure cultures of 9 Streptococcus spp. in media containing different added chemicals revealed that thallium acetate was the least harmful to the generation rate of all test species. Sodium azide follows in that respect except for Strep. uberis. Potassium tellurite tends to produce marked reductions in the generation rate of some species and completely inhibits the log phase in others. The tellurite tolerant species include Strep. faecalis var. zymogenes, Strep. faecalis var. liquefaciens, Strep. pyogenes, Strep. agalactiae and Strep. uberis. The tested Strep. faecalis strain demonstrated an inhibition of the log phase at tellurite concentrations between 0.05 and 0.7%. Sensitive species failing to proceed in a log phase of growth in the presence of 0.01% tellurite concentration include Strep. durans, Strep. lactis and Strep. bovis. The highest number of cell recoveries from the sensitive species may be made at 6 h incubation.

Employing potassium tellurite, sodium azide, and thallium acetate broths, 361 strains of fecal streptococci were isolated from 142 farm animals representing 11 species. Although none of the three media gave 100% recovery, their collective use made it possible to obtain at least one fecal streptococcus strain from every fecal sample.Results of biochemical tests revealed that 14.8% were S. bovis, 12.7% were S. faecalis var. liquifaciens, and the remaining 72.5% were atypical faecalis groups.Using the 361 isolates from animal fecal material for validating the heat resistance and heat-tellurite tolerance tests for the differentiation between animal and human fecal streptococci strains, it was found that not one of these isolates could survive these combined tests. The importance of these tests is discussed.

A study of 300 samples, representing 14 different unbottled drinks, indicated that there are three vitally important criteria pertaining to their bacteriological examination. First, the total viable counts may be better accomplished by the pour-plate method, using enriched media, with incubation at either 30 or 37 C. Second, a comparative study of the coliaerogenes group and the enterococci as indices of pollution unquestionably favors the latter as the reliable indicator, owing to false interpretations of the presumptive test and to lack of accurate definition of fecal and nonfecal coliforms recovered from positive cases. The use of enterococci, however, did not provide as reliable an indicator as the pour-plate method. Third, the results with enterococci, in defining the probable source of pollution, are more precise. Experiments judiciously selected and simultaneously conducted revealed that the heat and heat-tellurite resistance tests, and the tetrazolium-reduction test, matched in relating 98.9% of available enterococci to an animal source. Negligible but vital discrepancies were obtained with the two odd strains which qualified as human-derived according to the heat and heat-tellurite resistance tests. The differential criterion of Skadhauge and Barnes, based on the failure of animal-derived enterococci to grow in the presence of a low concentration of potassium tellurite, did not apply to the other two methods, since 99.5% of the recovered strains were found tolerant to the specified tellurite concentration.

The isolation of faecal streptococci from the excreta of man, cattle and sheep was investigated. The methods compared were (a) heat, (b) tetrathionate, (c) tellurite, (d) thallium salts. The tellurite method proved highly efficient, isolating 97% of strains from human, cow and sheep faeces. A survey of the properties of strains isolated was made. Differential tests based on (a) heat resistance and (i) reducing properties were devised; these divided the streptococci isolated by the tellurite method into groups, some of which were characteristic of the source. The information available seems capable of distinguishing many strains obtained from man from those derived from cows or sheep, and it is suggested it may be of use in tracing sources of pollution in water, milk and other foodstuffs.