PubMed Health⌕ Search

Biomedical subjects

H Moser

Publications and source records attributed to H Moser.

At least 19 recordsLinked to original sources
PubMed1992

Mutations in the 70K peroxisomal membrane protein gene in Zellweger syndrome.

The peroxisomal membrane protein, with a relative molecular mass of 70,000 (M(r) 70K) (PMP70), is an important component of peroxisomal membranes and an ATP-binding cassette protein. To investigate its possible involvement in Zellweger syndrome (ZS), an inborn error of peroxisome assembly, we cloned and sequenced cDNAs for human PMP70 and mapped the gene to chromosome 1. Amongst 32 probands with ZS or related disorders, we found two mutant PMP70 alleles in single ZS probands from the same complementation group. One allele has a donor splice site mutation and the second a missense mutation. Our results suggest that PMP70 plays an important role in peroxisome biogenesis and that mutations in PMP70 may be responsible for a subset of ZS patients.

ATP-Binding Cassette Transporters↗
PubMed1992

Uniparental origin of sex chromosome polysomies.

The parental origin of the additional sex chromosomes in 8 cases with high-order sex chromosome polysomies was determined using DNA polymorphisms. The additional sex chromosomes were paternally derived in 3 48,XXYY cases, and maternal in origin in 1 48,XXXY case and 4 49,XXXXY cases. Thus, all extra chromosomes, within a particular patient, were always derived from only one parent. Their most likely origin was successive nondisjunction at the first and second meiotic division in one germ cell. The mechanism involved remains unclear, but appears to be independent of parental ages.

Humans↗
PubMed1992

Interferon-gamma-induced expression of tissue factor activity during human monocyte to macrophage maturation.

The expression of tissue factor (TF) during differentiation of human monocytes (MO) to macrophages (MAC) in vitro is investigated in this study. In MO, TF activity can be induced by the addition of lipopolysaccharides (LPS) as detected by Northern blot analysis and measured functionally as procoagulant activity (PCA), while IFN gamma alone has only marginal stimulatory activity. During in vitro differentiation of MO into MAC, however, there is a steady increase in IFN gamma-induced PCA with a maximum on day 7. While MO during the first 2 days in culture are more responsive to LPS, IFN gamma becomes the prominent stimulus for mature MAC. The response to IFN gamma is rapid with a peak within 6-8 h and a subsequent downregulation to baseline activity within 24 h. Our results demonstrate that IFN gamma can effectively induce TF in human MAC and that its expression is developmentally regulated during MO to MAC maturation in vitro.

Blood Coagulation Factors↗
PubMed1992

Genotype/phenotype association in cystic fibrosis: analyses of the delta F508, R553X, and 3905insT mutations.

A striking clinical phenomenon of cystic fibrosis is the heterogeneous disease expression. It must therefore be assumed that the nature of the mutations associated with cystic fibrosis might partly determine the phenotypic manifestations. The relation between the cystic fibrosis mutations delta F508, R553X, and 3905insT and clinical parameters such as sweat test electrolytes, age at chronic Pseudomonas aeruginosa colonization, Chrispin-Norman x-ray scores, and relative underweight have been investigated in 45 patients homozygous for delta F508 (delta F2), in 12 compound heterozygotes for delta F508/R553X (delta F1/RX1), in three R553X homozygotes (RX2), and in 13 patients compound heterozygous for delta F508/3905insT (delta F16). We have found significant differences between the genetically defined subgroups concerning the mean age at onset and the cumulative incidence of chronic P. aeruginosa colonization and Chrispin-Norman x-ray scores. The significant results as well as some trends regarding the relative underweight demonstrate a milder clinical course in R553X heterozygotes and more severe disease in the delta F16 group compared to delta F508 homozygotes. The three patients homozygous for R553X presented with a two-stage course showing mild progression before P. aeruginosa infection and as severe a course as the delta F16 patients after P. aeruginosa colonization at the age of 12 y. The findings presented here indicate that specific mutations can influence the severity and progression of the disease, implicating the importance of mutation and haplotype analyses. However, wide variations within the genetically homogeneous subgroups illustrate that other determinants of the clinical status do exist.

Adolescent↗
PubMed1991

X-linked centronuclear myopathy: mapping the gene to Xq28.

The X-linked recessive centronuclear/myotubular myopathy (XLR-CNM/MTM1), a severe neonatal disorder characterized by generalized hypotonia, muscle weakness and primary asphyxia, has recently been mapped to Xq28. This report presents linkage analysis data of eight families with X-linked centronuclear myopathy. Four probes from the region Xq26-27 and five Xq28 probes were used to get more precise gene localization and marker order. St14 (DXS52), fully informative in all families, shows significant linkage to the CNM gene (z = 3.60; theta = 0.05), followed by DX13 (DXS15) (z = 2.03; theta = 0.06) and F8 (z = 1.86; theta = 0.00). Combination of the physical map derived by Kenwrick and Gitschier (1989) and our linkage data lead to the most probable order R/GCP-G6PD-(XLR-CNM-F8)-p767-St14-cpX67-++ +DX13 placing the CNM gene close to F8. The results of this study confirm strong linkage of the CNM gene to the region Xq28 and will permit carrier testing and prenatal diagnosis in CNM families. We conclude that the precise localization of this devastating disorder may be of great importance for genetic counselling in families at risk. The lack of information about gene frequency and mutation rate as well as the severity and burden of the disease point to the inevitable need for accurate clinical diagnosis.

Chromosome Mapping↗
PubMed1991

Behavioral treatment of sleep dysfunction in patients with the Rett syndrome.

Aberrant sleep patterns are commonly experienced by girls with the Rett syndrome. In this investigation, the problematic sleep of three girls with the Rett syndrome was regulated using a bedtime fading procedure with response cost. The treatment involved systematically delaying the bedtime and utilized a response cost component, removing the child from bed for one hour, when the child did not experience short latency to sleep onset. Daytime sleep was interrupted, except during regularly scheduled naps. A fading procedure was then successfully utilized to advance the bedtimes. This treatment resulted in more regular sleep patterns for the girls by increasing appropriate nighttime sleep, reducing inappropriate daytime sleep and reducing problematic nighttime behaviors (e.g., night wakings). These preliminary findings are important because they suggest that the dysfunctional sleep patterns of girls with the Rett syndrome may be amenable to behavioral treatments.

Behavior Therapy↗
PubMed1991

Association between haplotypes and specific mutations in Swiss cystic fibrosis families.

Cystic fibrosis (CF) is the most common severe autosomal recessive genetic disorder in Caucasian populations, with an incidence of about 1 in 2000 live births, implying a carrier frequency of about 1 in 22. In 1989, the CF gene was isolated and characterized and the major mutation (delta F508), a 3-bp deletion that results in the loss of a phenylalanine residue at position 508, was detected. To determine the frequency of the delta F508 mutation and the predicted number of additional mutations in our population, we have undertaken a collaborative study of 215 CF patients and 175 CF parents in Switzerland. The delta F508 mutation in exon 10 has been found in 70% of the CF chromosomes, and the exon-11 mutation R553X seems to be the second most common CF mutation in our population, with a frequency of 5.3%, whereas the G551D mutation (also in exon 11) has not been detected at all. Haplotype determination of 430 CF and 175 normal chromosomes using XV-2c, KM19, MP6d-9, and J3.11 has been proven to be very helpful in providing additional carrier risk calculations: Haplotypes 1 (1221), 2 (1222), 6 (2111), and 7 (2221) increase the risk of being a carrier from 1 in 55 (haplotype 6) to 1 in 17 (haplotype 1), whereas haplotypes 3 (1122), 4 (1112), 8 (2222) and 10 (1111) lower the risk from 1 in 144 (haplotype 3) to 1 in 1678 (haplotype 10). Moreover, the mutation R553X shows strong correlation with haplotype 3, leading to the suggestion that haplotypes 1, 2, 5, and 6 may account for four additional mutations in Switzerland.(ABSTRACT TRUNCATED AT 250 WORDS)

Chromosome Aberrations↗
PubMed1991

Altered neurochemical markers in Rett's syndrome.

Rett's syndrome (RS) is a neurologic disorder associated with severe mental deficiency and neurologic manifestations of cortical and extrapyramidal origin. The present report is a preliminary postmortem brain study that compares the levels of endogenous biogenic amines and selected neurotransmitter receptors in five cases with RS and six normal controls of similar age. The level of choline acetyltransferase activity was reduced in several cortical and subcortical regions. Endogenous levels of dopamine in the superior frontal and superior temporal gyri, occipital cortex, and putamen were reduced. The changes in specific neurotransmitter markers, particularly those associated with the basal ganglia and cortex, may underlie the progressive deterioration in motor and cognitive function characteristic of this progressive disorder.

Adolescent↗
PubMed1990

Cognitive impairment in adult-onset adrenoleukodystrophy.

Adrenoleukodystrophy (ALD) is a progressive X-linked disorder that produces pathological changes, mainly in the adrenal cortex and the white matter of the central nervous system. The main biochemical abnormality is the accumulation of saturated unbranched fatty acids with a chain length of 24 or more, referred to as very-long-chain fatty acids (VLCFA). Affected children develop large zones of demyelination associated with perivascular lymphoctyic infiltrations resembling those seen in multiple sclerosis. Adults show a more chronic form of the disease, referred to as adrenomyeloneuropathy (AMN). AMN mainly involves the spinal cord ad peripheral nerves, although the cerebral hemispheres may also be affected. Approximately 15% of female carriers have nervous-system involvement that resembles AMN. It is well known that ALD may initially appear as a psychiatric disorder. In the present study, we have assessed the prevalence of cognitive impairment in a group of AMN patients and neurologically symptomatic ALD heterozygotes initially presenting primarily physical complaints. Sixty percent of these patients demonstrated significant neuropsychological impairment, most commonly a pattern of spared and impaired functions typical of a subcortical dementia. We suggest that this progressive cognitive impairment may underlie other behavioral deficits, affirming the significance of the psychological features of this genetically determined disorder.

Adrenoleukodystrophy↗
PubMed1990

Haplotype analysis for CF-linked DNA polymorphisms in Switzerland.

A total of 295 patients, parents and unaffected sibs from 106 CF-families in central and northeastern Switzerland were investigated with probes 7C22(D7S16), metH, metD, pKM19, pXV-2c and pJ3.11(D7S8) for eight DNA polymorphisms (RFLP's). Linkage disequilibrium to the CF locus and haplotype frequencies were compared to those in other populations. They are comparable to other Caucasian populations and, for pKM 19 and pXV-2c, very close to the findings in Italy. The prevalence of certain haplotypes among the CF and the normal allele-bearing chromosomes indicate that the majority of the CF cases are probably the result of one ancient mutation in a common ancestor, but that there may be allelic heterogeneity accounting for an important proportion of patients, that may differ between countries or regions. Informative family constellations for the different polymorphisms in Switzerland and strategies for carrier detection and prenatal diagnosis are discussed. Haplotype analyses for each country and its ethnic subgroups are recommended.

Chromosome Mapping↗
PubMed1990

RFLPs for Duchenne muscular dystrophy cDNA clones 9 and 10.

The complete 14-kb cDNA for the gene causing the X-linked recessive muscular dystrophy (MD) type Duchenne (DMD) and Becker (BMD) has recently been cloned and made available for deletion/duplication screening in patients. It detects 65 exon-containing nonpolymorphic HindIII fragments spread over a gene locus of about 2,000 kb. When the entire DMD cDNA is used, deletions/duplications can be found in about 65%-70% of affected patients, permitting direct carrier detection by densitometric scanning. But in cases where no deletion/duplication is detectable, RFLP analysis, specially favored within the gene, will be the method for carrier-status determination. Clones 9 and 10-1.2-kb and 0.7-kb fragments, respectively, of the 14-kb DMD cDNA--have been hybridized with human genomic DNA digested by nine different restriction enzymes. Five RFLPs, involving Asp700, PvuII, XbaI, and EcoRV sites, were detected, and Mendelian inheritance could be demonstrated. Since clones 9 and 10 are localized telomeric to the mutation-hot-spot region, their polymorphisms are thought to be very helpful as flanking markers for indirect carrier detection in families with a family history of DMD/BMD. Moreover, these RFLPs can be used for direct carrier detection or exclusion in families with patients showing a deletion/duplication in the region of p9 or p10.

Blotting, Southern↗
PubMed1979

Intra- and extravascular volume changes in the human forearm after static hand grip exercise.

Studies have been conducted to evaluate intra- and extravascular volume changes and blood flow in the exercising human forearm by means of (1) combining plethysmographic and scintigraphic methods, (2) an indirect procedure using the relationship of blood flow and volume change from reactive hyperemia. A static hand grip exercise of 60% maximal voluntary contraction and 30 s duration increased the forearm volume by 3.03 +/- 0.65 ml/100 ml soft tissue, involving both the intra- and extravascular volume components. There is a quantitative and qualitative difference in the time course of change in these components, showing an extravascular part of about 50% for the 2-min post-exercise value and a substantially slower rate of recovery. Experiments involving muscle work at intervals (50% maximal voluntary contraction, 30 s duration, 2-min intervals) caused a further increase in extravascular volume. Furthermore, the study suggests that the flow-volume relationship from reactive hyperemia may be considered to be available for the determination of local blood volume changes in exercise hyperemia. The results are discussed in connection with the influence of anaerobic muscle metabolism and conclusions referring to this are drawn about the use of plethysmographic methods.

Adult↗