Biomedical subjects

Timo Palosuo

Publications and source records attributed to Timo Palosuo.

24 records · Page 2Linked to original sources

PubMed2002

Quantitation of latex allergens.

Minimizing allergen concentration in latex goods to prevent sensitization to natural rubber latex (NRL) and thereby the development of clinical allergy is acknowledged as of mutual interest for rubber manufacturers and regulatory health authorities. However, measuring total protein, the principal currently available method, cannot be deemed a satisfactory regulatory measure to control allergen content. Specific methods based on human IgE-containing reagents, such as radioallergosorbent test (RAST) inhibition, have been available in certain laboratories for demonstrating NRL allergens in rubber products but the methods lack standardization. Currently, one commercial test has become available for measuring individual NRL allergens by capture ELISA-based assays using monoclonal antibodies and purified or recombinant allergens. Such methods are specific, they can be properly standardized, and they are of sufficient sensitivity and reproducibility. Results from medical gloves collected in two national market surveys in Finland in 1995 and 1999, respectively, show that Hev b 6.02 and Hev b 5, the two major allergens for NRL-allergic adults, are the most abundant allergens regularly detectable in high- and moderate-allergen gloves. In addition, Hev b 3 and Hev b 1, the two major allergens for children with spina bifida, are also commonly found. In general, when the sum of the four allergens exceeded 1 microg/g, most NRL-allergic patients showed positive skin prick test reactions against them. Using these new methods assessment of threshold levels that could in due course become guidelines for the rubber industry and regulatory health authorities is becoming possible. Eventually, this progress is expected to lead to a declining incidence of latex allergy.

Allergens↗

PubMed2002

The association of sensitive systemic inflammation markers with bronchial asthma.

BACKGROUND: Airway inflammation is a characteristic feature of bronchial asthma. Previous studies have shown an increased local inflammatory activity in the airway mucosa of asthma patients. OBJECTIVES: To analyze the association of asthma with three sensitive markers of systemic inflammation, C-reactive protein, serum amyloid-A (SAA), and plasma fibrinogen. METHODS: A cross-sectional, population-based study including 1,513 Finnish men aged 45 to 74 years, who participated in a chronic disease risk factor survey in 1997. Of the participating men, 97 were classified as asthma patients. The odds ratios of asthma were analyzed by quartile of each inflammation marker. RESULTS: In logistic regression models the age-adjusted odds ratios (second, third, and fourth quartile as compared with the first quartile) of asthma increased gradually with increasing quartile of C-reactive protein (1.28, 1.19, 1.96, P for trend = 0.039), SAA (1.20, 3.00, 3.49, P for trend < 0.001), and fibrinogen (1.22, 1.79, 3.16, P for trend < 0.001). The associations were independent of smoking. Further adjustment for waist-to-hip ratio, a marker of central obesity, and symptoms of chronic bronchitis weakened the observed association, but the increasing trend in the association of SAA and fibrinogen with asthma remained highly significant. CONCLUSIONS: Sensitive markers of systemic inflammation, particularly SAA and fibrinogen, were positively and significantly associated with asthma prevalence. These findings support the hypothesis that not only local, but also systemic, inflammation exist in bronchial asthma.

Aged↗

PubMed2002

Long-term outcome of 160 adult patients with natural rubber latex allergy.

Allergy to natural rubber latex is a major occupational problem in the health care sector and a problem even in other occupations in which protective gloves are used. There is little information available about the long-term outcome at work in large patient populations. To study the occupational outcome when all gloves in the working environment were changed either to low-allergen latex or non-latex gloves, in 1995 to 1996 we re-examined 160 of 174 adult subjects who were diagnosed with natural rubber latex allergy between 1982 and 1994 after a median of 3 years (range, 0.5 to 24 years) after the diagnosis. The outcome in daily work or as a patient in health care was investigated with the use of a questionnaire. Special attention was paid to the assessment of the occurrence of hand eczema. Glove selection policy as an intervention in the treatment of natural rubber latex allergy is described. Of 71 health care workers and 89 non-health care workers, 72% and 83% were atopic; 54% and 65% had hand eczema at the time of diagnosis, and 89% and 19% had work-related allergy to natural rubber latex, respectively. On re-examination, none of the health care workers had changed work because of natural rubber latex allergy, and only 38% had hand eczema (significant decrease). Ninety-eight percent of the non-health care workers, of which 58% had hand eczema, continued with their previous jobs. The use of low-allergen latex or non-latex gloves throughout the health care sector seems to be an adequate step for health care workers who have natural rubber latex allergy; nonhealth care workers get along with personal avoidance of latex gloves if they are not working directly with natural rubber latexcontaining materials in production.

Adult↗

PubMed2002

Recent developments in latex allergy.

PURPOSE OF REVIEW: Immediate allergic reactions to natural rubber latex continue to be an important medical and occupational health problem. In this review we focus on progress made in understanding the significance of occupational exposure and epidemiology, risk groups, diagnosis and prevention of natural rubber latex allergy. We also discuss methods aimed at quantification of clinically relevant natural rubber latex allergens and studies on B-cell epitopes of major natural rubber latex allergens. RECENT FINDINGS: Prospective studies have been published focusing on the prevention of natural rubber latex allergy. Efforts to identify and characterize new natural rubber latex allergens were continued in several research groups. The use of purified allergens or proteins produced by recombinant DNA technology was assessed in studies aimed at improving the diagnosis of natural rubber latex allergy as well as in developing quantitative methods for the measurement of specific natural rubber latex allergens. For the first time, conformational immunoglobulin E epitopes were identified in a major natural rubber latex allergen, hevein, using a novel chimera-based allergen epitope mapping strategy. SUMMARY: Measures taken in health care to reduce exposure to natural rubber latex products seem to be effective in reducing the number of new sensitizations. A few new minor natural rubber latex allergens, probably important in allergen cross reactions, were identified, and some nonmedical natural rubber latex products were found to be potentially dangerous to natural rubber latex-allergic patients. Sensitive and specific immunoassays for quantification of clinically relevant natural rubber latex allergens in manufactured products were developed in some laboratories. These assays may eventually replace the nonspecific total protein measurement, currently advocated by health authorities in the indirect estimation of allergen amounts in natural rubber latex products. Knowledge about conformational immunoglobulin-binding B-cell epitopes of major allergens is expected to be helpful in designing optimal reagents to specific immunotherapy.

Allergens↗

PubMed2002

Association of mannan-binding lectin deficiency with venous bypass graft occlusions in patients with coronary heart disease.

We investigated the effect of mannan-binding lectin (MBL) deficiency on the susceptibility to bypass graft occlusion in 62 patients with coronary heart disease. MBL deficiency appeared to be associated with occlusion (p = 0.0099). A high level of anti-cardiolipin IgG as well as the number of venous bypass grafts were also involved (p = 0.0018 and p = 0.0104, respectively). Since early occlusion (<5 years after surgery) of a venous bypass graft is considered to be caused by thrombosis or fibro-intimal hyperplasia superimposed by thrombosis, our finding also implies an association of MBL deficiency with thrombotic events. It remains unclear whether the previously confirmed effect of MBL deficiency in coronary disease is mediated through this possible thrombotic mechanism, or whether plaque formation is also involved in the process. Further studies are clearly warranted.

Adult↗

PubMedDate not supplied

Allergen cross-reactivity between proteins of the latex from Hevea brasiliensis, seeds and pollen of Ricinus communis, and pollen of Mercurialis annua, members of the Euphorbiaceae family.

Allergen cross-reactions among three strongly sensitizing Euphorbiaceae species, i.e., the rubber tree (Hevea brasiliensis), castor bean (Ricinus communis), and the Mediterranean weed Mercurialis annua were studied in Finnish patients (n = 25) allergic to natural rubber latex (NRL), but with no known exposure to castor bean or M. annua, and French patients allergic to castor bean (n = 26) or to M. annua (n = 9), but not to NRL. In immunoglobulin E (IgE)-immunoblotting, 28% of NRL-allergic patient sera recognized castor bean seed and 48% reacted to castor bean pollen proteins. Likewise, 35% of the NRL-allergic patient sera bound to M. annua pollen allergens. Nineteen percent of castor bean-allergic patients showed IgE to NRL and 8% to M. annua proteins. Sera from patients allergic to M. annua reacted in 44% to NRL, in 56% to castor bean seed, and in 78% to castor bean pollen proteins. In immunoblotting, castor bean seed extract inhibited the binding of NRL-reactive IgE to 20 kDa, 30 kDa of NRL, and 55 kDa of proteins; NRL extract, in turn, inhibited the binding of castor bean-reactive IgE to 14, 21-22, 29, and 32-34 kDa of castor bean proteins. In ELISA inhibition, NRL extract inhibited 33% of the binding of M. annua--reactive IgE of pooled sera to M. annua pollen. In conclusion, allergen cross-reactivity in vitro was observed among three botanically related Euphorbiaceae members, H. brasiliensis, R. communis, and M. annua, but the molecular specificity of the observed cross-reactions as well as their clinical significance remains to be elucidated. Allergen cross-reactivity should be taken into account in diagnostic work.

Adolescent↗