Biomedical subjects

P Reitmeir

Publications and source records attributed to P Reitmeir.

11 recordsLinked to original sources

PubMed1992

Month of birth and allergic disease at the age of 10.

The relationship between month of birth and asthma, hay fever and skin sensitization to mixed grass pollen was analysed in a population-based cross-sectional study in Munich and Bavaria 1989-1990 of 6535 10-year-old children. The relative risk of developing atopic disease is calculated by comparing the prevalence in a single month with the prevalence of all other months. A slightly increased risk of developing allergic skin sensitization for grass pollen (n = 1128) was found for February (odds ratio, 1.3, 95% confidence interval 1.0-1.6), May (1.4, 1.1-1.8) and June (1.3, 1.0-1.6). For hay fever (n = 379) an increase was found for May (1.5, 1.0-2.1) and for allergic asthma (n = 277) for August (1.4, 1.0-2.1). A protective effect was observed for certain months of birth; September for allergic sensitization (0.8, 0.6-1.0), October for and November for hay fever (0.6, 0.3-0.9). The occurrence of hay fever and positive prick test is explained by the seasonal variation of atmospheric grass pollen and the peak in August of asthmatic patients by house dust. Date of birth appears therefore to slightly influence the risk of developing an allergic sensitization and allergic diseases.

Child↗

PubMed1992

Genetic risk for asthma, allergic rhinitis, and atopic dermatitis.

In order to explore the genetic risk of a child with a family history of allergies developing asthma, allergic rhinitis, or atopic dermatitis, questionnaires filled in by 6665 families were analysed. The data were collected in a population based cross sectional survey of 9-11 year old schoolchildren living in Munich and southern Bavaria. The relation between asthma, allergic rhinitis, and atopic dermatitis and the number of allergic first degree relatives, and the type of allergic disease was examined. Analyses were done separately for families with single or multiple allergic diseases. In families with one allergic parent the risk of the child developing asthma was increased by asthma in a parent, with an odds ratio (OR) of 2.6 (95% confidence interval 1.7 to 4.0) but not by parental allergic rhinitis with OR 1.0 (0.7 to 1.5) or atopic dermatitis, OR 1.0 (0.6 to 1.6). For allergic rhinitis the highest risk with OR 3.6 (2.9 to 4.6) was observed with allergic rhinitis of one parent, apparently lower for asthma of one parent, OR 2.5 (1.6 to 4.0) or atopic dermatitis, OR 1.7 (1.1 to 2.5). Children with parental atopic dermatitis had a high risk for atopic dermatitis, OR 3.4 (2.6 to 4.4), compared with children with parental asthma, OR 1.5 (1.0 to 2.2), or parental allergic rhinitis, OR 1.4 (1.1 to 1.8). Risk factors in families with combined allergies of two relatives (parents and siblings) were analysed separately for the different combinations. These results support the hypothesis that asthma, allergic rhinitis, and atopic dermatitis are multifactorial diseases brought about by various familial and environmental influences.

Asthma↗

PubMed1992

[Effects of passive smoking on the pediatric respiratory tract].

OBJECTIVE: To explore the risk of parental smoking to the respiratory health of their children data of a cross sectional study on fourth-grade schoolchildren in Munich and Southern Bavaria were analysed. METHODS: Allergic and asthmatic diseases and symptoms, risk factors like family history, indoor pollution and parental smoking were evaluated by a questionnaire. Pulmonary function tests were performed in 7284 school children aged (9-11 years). Lung function values were adjusted for height, weight, sex and other confounders. RESULTS: The children, whose parents smoke at home, had significantly lower levels of peak flow, MEF75, MEF50 and MEF25 compared to children from non-smoking families, with a dose-response relationship. Smoking of more than 20 cigarettes at home is associated with a mean decrease in MEF75 of 5.7%, in MEF50 of 4.9% and in Peak Flow of 4.9% (p < 0.001). The prevalence of cough and wheezing increased with increasing smoking rates of the parents. CONCLUSIONS: Passive exposure to smoke has direct measurable dose-dependent effects on the respiratory system of children.

Asthma↗

PubMed1991

A mutation resulting in increased triosephosphate isomerase activity in Mus musculus.

A mutation resulting in increased triosephosphate isomerase (TPI) activity in blood was recovered in offspring of procarbazine hydrochloride-treated male mice. Breeding experiments indicated a codominant mode of expression. Compared to the wild type, heterozygous and homozygous mutants have mean erythrocyte TPI activities of approximately 140 and 190%, respectively. Besides blood and erythrocytes the increased activity is expressed to a similar degree in spleen, and to a lesser degree in liver, lung, kidney, muscle and brain. Enhanced activity was absent in the heart. Heterozygous and homozygous mutants are viable, fully fertile and exhibit no significant differences in haematological or other physiological traits studied. Biochemical investigations of TPI in both mutant genotypes revealed neither physicochemical nor kinetic differences compared to the wild type. Moreover, immunoinactivation studies showed no difference in the amount of antiplasma required to inactivate a constant amount of TPI activity in all three genotypes, strongly suggesting that the differences in enzyme activity are attributable to differing amounts of enzyme protein expressed per cell. Mapping studies indicated that the mutation is closely linked to the Gapd locus and consequently is located either adjacent to or within the Tpi-1 structural locus. It is hypothesized that the mutation affected a regulatory element contiguous to the Tpi-1 structural locus which acts by increasing the amount of TPI expressed.

Animals↗

PubMed1991

Procedures for two-sample comparisons with multiple endpoints controlling the experimentwise error rate.

Clinical trials are often concerned with the comparison of two treatment groups with multiple endpoints. As alternatives to the commonly used methods, the T2 test and the Bonferroni method, O'Brien (1984, Biometrics 40, 1079-1087) proposes tests based on statistics that are simple or weighted sums of the single endpoints. This approach turns out to be powerful if all treatment differences are in the same direction [compare Pocock, Geller, and Tsiatis (1987, Biometrics 43, 487-498)]. The disadvantage of these multivariate methods is that they are suitable only for demonstrating a global difference, whereas the clinician is further interested in which specific endpoints or sets of endpoints actually caused this difference. It is shown here that all tests are suitable for the construction of a closed multiple test procedure where, after the rejection of the global hypothesis, all lower-dimensional marginal hypotheses and finally the single hypotheses are tested step by step. This procedure controls the experimentwise error rate. It is just as powerful as the multivariate test and, in addition, it is possible to detect significant differences between the endpoints or sets of endpoints.

Biometry↗

PubMed1990

Osmotic state of lenses in three dominant murine cataract mutants.

Three newly detected dominant cataract mutations (Asc-1, Cat-3vao, Tcm) were investigated for effects on osmotic alterations in the lenses of heterozygotes. The lens wet weight was reduced in two mutant lines (Cat-3vao and Tcm), and the water content in the lenses of the Cat-3vao mice was increased. Moreover, in the cataractous lenses from Cat-3vao mice, the sodium-potassium-adenosine triphosphatase (Na(+)-K(+)-ATPase) activity was enhanced and the ATP concentration, correspondingly decreased. The osmotic variations observed in the Cat-3vao mutants might have been due to a metabolic response to the yet unknown, primary pathological event. The lenses of the other two mutant lines (Asc-1 and Tcm) revealed no alterations that could be related to osmotic stress. In no mutant line investigated could a decrease in Na(+)-K(+)-ATPase activity be demonstrated that was similar to the causative factor in the Nakano mutant line. The Cat-3vao mice exhibited some similarities to the Philly mutant line.

Adenosine Triphosphate↗

PubMed1990

Histological and biochemical characterization of the murine cataract mutant Nop.

Nop, a spontaneous murine dominant cataract mutation, was detected by slit lamp investigations and preliminary characterized as a nuclear opacity. Histological investigations confirmed these findings and revealed additionally polar cataracts with vacuolization. In contrast to wild-type lenses, the nuclei of the cortical cells could also be detected in the area of the lens nucleus in Nop lenses. No other pathological alterations were found in the eyes. Lens wet and dry weights, as well as the content of water-soluble lens proteins, were reduced in heterozygous and homozygous mutants. The body weight was only slightly altered, indicating a rather lens-specific growth retardation. Some parameters concerning the osmotic state of the lens were changed, however, only in the homozygous mutants. Electrophoresis of the water-soluble lens proteins of the mutants revealed either additional bands, not present in the wild types, or bands of overrepresented proteins only slightly present in wild-type lenses. The changes might be related to the reduced amount of gamma-crystallins, which alters the composition of lenticular proteins in the mutants. Northern blots probed with cDNA specific for alpha-, beta- or gamma-crystallin genes suggested a reduced transcription of the gamma-crystallin genes. In contrast, the transcription of alpha- and beta-crystallins appeared to be similar in wild type and the mutants. The selective reduced amount of gamma-crystallin specific RNA can be discussed as a biochemical indicator for the histologically observed changes of differentiation in the cataractous Nop lenses.

Animals↗

PubMed1990

Characterization of Cat-2t, a radiation-induced dominant cataract mutation in mice.

A dominant cataract mutation was detected recently among the offspring of x-ray-irradiated male mice. The mutation, which causes total lens opacity, has provisionally been designated by the gene symbol Cat-2t. In the lenses of heterozygous and homozygous Cat-2t mutants, the epithelial and fiber cells were swollen and the lens capsule was ruptured. The histologic analysis demonstrated a complete destruction of the cellular organization of the lens, which might be caused by its altered developmental processes. The data derived from biochemical investigations indicate that biochemistry of the cataractous Cat-2t lenses is affected: the osmotic state as indicated by the increased water content and increased Na(+)-K(+)-adenosinetriphosphatase (ATPase) activity; the energy state as indicated by the decreased adenosine triphosphate (ATP) concentration; and the redox state as indicated by the enhanced content of oxidized glutathione. Additionally, the lenticular protein composition is altered because of the presence of vimentin in the water-soluble fraction. This cannot be explained by the enhanced crosslinking activity of transglutaminase. The changes of the osmotic, energy, and redox states are considered to be secondary in relation to the altered lenticular development. In contrast, the variations concerning vimentin and transglutaminase might be a biochemical indication of the changed development. Possible similarities to other dominantly expressed murine cataract mutants are discussed.

Adenosine Triphosphate↗

PubMed1989

Characterization of Scat (suture cataract), a dominant cataract mutation in mice.

The autosomal, dominant mutation Scat (suture-cataract) was found in (101/El x C3H/El)F1-hybrid mice. The severity of the cataract is dependent on the gene dose. The mutation causes an anterior suture opacity in heterozygotes amd microphthalmia with vacuolated lenses in homozygotes. In histological sections of lenses the heterozygotes exhibit a hydropic swelling of lens epithelium, whereas in homozygotes interruption and degeneration of lens fibers as well as clefts and folds of the capsule were observed. The mutation has a complete penetrance and constant expressivity. The body weight of the mutants is not altered; the mutation has no effects on fertility or viability. The lens wet and dry weights are diminished (more pronounced in the homozygotes). The water content of the lens is enhanced only in the homozygous Scat mutants. Biochemically, the lenticular content of water-soluble proteins is decreased in the homozygous Scat mutants. By electrophoresis, in the lenses of homozygous Scat mutants a different pattern of water-soluble proteins could be observed. The lenses of both, heterozygous and homozygous Scat mutants exhibit enhanced Na+,K+-ATPase activity and a decreased ATP concentration. The genetical, morphological or biochemical data suggest that the effect of the Scat mutation is distinct from other described cataract mutations in mice.

Animals↗

PubMed1989

Oxidative stress and inherited cataracts in mice.

To determine whether an unbalanced redox state might accompany the development of particular inherited mouse cataracts, the lenticular content of oxidized glutathione (GSSG) and the activity of superoxide dismutase (SOD) were chosen as markers. For wild-type lenses, an enhanced GSSG content could be observed in females as compared to males. Such a sex effect could not be detected for the SOD activity. In the mutants, GSSG content in cataractous lenses was found to be enhanced in 2 of 7 cases; the increases in other mutants were not significant. Changes of the SOD activity were even less consistent and only a random correlation of GSSG content and SOD activity with cataractogenesis could be deduced.

Animals↗

PubMed1989

[Are there risk factors for stenosing laryngitis? Results of the Southern Bavaria pseudo-croup study].

We tried to find a correlation between elevated air pollution levels and incidences of laryngitis (pseudocroup). Clinical data-obtained by questionnaire-from 418 children with laryngitis, viral shedding in rhinal secretion and data on air pollution as SO2, NO2 and dust levels were compared via correlation analyses. Boys with allergic diathesis and with signs for bronchial hyperreactivity were identified as a high risk group. The high incidence of laryngitis especially seen in the month of October could be explained by the increased number of RSV positive patients. There was no significant correlation between laryngitis and the air pollution levels during the time of observation.

Air Pollution↗