Aktives Altern und Lebensqualität

Based on the Active Ageing Programme of the World Health Organization (WHO), a demonstration project was conducted in a city in North-Rhine Westphalia between October 2002 and December 2004. The aim of the study was to promote an active ageing process, to maintain autonomy and independence among older people, and thereby to promote health and quality of life. The target group included people aged 55 to 80 years. The aim was to include older persons in a critical period of life due to loss of partner within the last five years and people undergoing a status change due to retirement within the last two years. 344 participants were visited at home to assess their health and psychosocial situation and to identify opportunities for activities. Participants were supported in their efforts to realise the agreed-upon activities. In this article results of the external evaluation are presented. It is analysed whether quality of life according to the WHOQOL Bref improves among participants in the course of the project. Results of non-parametric tests show small differences in quality of life between the three waves of interviews (at the beginning of the project, after one year, at the end of the project). This holds true when only those participants are analysed who retired within the last two years. However, quality of life significantly improves among older persons who lost their partner within the last five years. In terms of implementation of the WHO Active Ageing Programme results suggest application of a risk group strategy.

The hereditary adult-onset ataxias in South Africa

There is little data on the spectrum and frequencies of the autosomal dominant spinocerebellar ataxias (SCAs) from the African continent. We undertook a large prospective population-based study over a 10-year period in South Africa (SA). Affected persons were clinically evaluated, and the molecular analysis for the SCA1, 2, 3, 6 and 7 expansions was undertaken. Of the 54 SA families with dominant ataxia, SCA1 accounted for 40.7%, SCA2 for 13%, SCA3 for 3.7%, SCA6 for 1.9%, SCA7 for 22.2% and 18.5% were negative for all these mutations. The frequency of the SCA1 and SCA7 expansions in SA represents one of the highest frequencies for these expansions reported in any country. In this study, the SCA7 mutations have only been found in SA families of Black ethnic origin.

Cloning, sequence, and developmental expression of a type 5, tartrate-resistant, acid phosphatase of rat bone

Tartrate-resistant acid phosphatase (TRAP) is a characteristic constituent of osteoclasts and some mononuclear preosteoclasts and, therefore, used as a histochemical and biochemical marker for osteoclasts and bone resorption. We now report the isolation of a 1397-base pair (bp) full-length TRAP/tartrate-resistant acid ATPase (TrATPase) cDNA clone from a neonatal rat calvaria lambda gt11 cDNA library. The cDNA clone consists of a 92-bp untranslated 5'-flank, an open reading frame of 981 bp and a 324-bp untranslated 3'-poly(A)-containing region. The deduced protein sequence of 327 amino acids contains a putative cleavable signal sequence of 21 amino acids. The mature polypeptide of 306 amino acids has a calculated Mr of 34,350 Da and a pI of 9.18, and it contains two potential N-glycosylation sites and the lysosomal targeting sequence DKRFQ. At the protein level, the sequence displays 89-94% homology to TRAP enzymes from human placenta, beef spleen, and uteroferrin and identity to the N terminus of purified rat bone TRAP/TrATPase. An N-terminal amino acid segment is strikingly homologous to the corresponding region in lysosomal and prostatic acid phosphatases. The cDNA recognized a 1.5-kilobase mRNA in long bones and calvaria, and in vitro translation using, as template, mRNA transcribed from the full-length insert yielded an immunoprecipitated product of 34 kDa. In neonatal rats, TRAP/TrATPase mRNA was highly expressed in skeletal tissues, with much lower (less than 10%) levels detected in spleen, thymus, liver, skin, brain, kidney, brain, lung, and heart. In situ hybridization demonstrated specific labeling of osteoclasts at endostal surfaces and bone trabeculae of long bones. Thus, despite the apparent similarity of this osteoclastic TRAP/TrATPase with type 5, tartrate-resistant and purple, acid phosphatases expressed in other mammalian tissues, this gene appears to be preferentially expressed at skeletal sites.

Subacute sclerosing panencephalitis. Changes on CT scan during acute relapse

A 19-year-old female patient presented in an acute state of akinetic mutism. Serological analysis of serum and cerebrospinal fluid demonstrated the presence of antibodies to measles virus. CT scan carried out during this acute phase of relapse demonstrated white matter enhancement affecting the cortical white matter of the frontal lobes and corpus callosum. These features indicate that active demyelination occurs during acute relapse in subacute sclerosing panencephalitis (SSPE) and suggest that immunotherapy should be considered during this acute phase.

The extracellular portion of HLA-DR alpha chain is composed of two compactly folded domains

A truncated form of the class II antigen DR alpha chain of the human major histocompatibility complex was produced in bacteria. A cDNA clone encoding the intact chain was modified so that the segment encoding the signal sequence was replaced by an ATG codon and the 3' region downstream to the part corresponding to the third exon was replaced by a stop codon. The new construct was put under the control of the Tac promoter in a bacterial expression vector. The distance between the Shine-Delgarno sequence and the initiation codon was randomized so that clones with optimal expression of the truncated DR alpha chain could be obtained after induced expression and immunoscreening. The truncated DR alpha chain was subjected to limited proteolysis with chymotrypsin, and the resulting cleavage products were analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. Two fragments were visualized by western blotting. Electrophoresis in the absence and presence of reducing agents suggested that one of the proteolytic fragments contained a disulphide bridge. It is concluded that the extracellular portion of the DR alpha chain is composed of two compactly folded domains connected by an extended stretch of the polypeptide chain.

Both alpha and beta chains of HLA-DC class II histocompatibility antigens display extensive polymorphism in their amino-terminal domains

At least three class II antigens, all composed of an alpha and a beta subunit, are encoded in the human major histocompatibility complex, i.e., DR, DC and SB. Two cDNA clones, encoding a DC alpha and a DC beta chain, respectively, were isolated from a cDNA library of the lymphoblastoid cell line Raji (DR3,w6). The two polypeptides predicted from the nucleotide sequences of these clones are each composed of a signal peptide, two extracellular domains, a hydrophobic transmembrane region and a short cytoplasmic tail. Comparison of the DC alpha sequence with two previously published partial sequences shows that the majority of the differences is located in the amino-terminal domain. The differences are not randomly distributed; a cluster of replacements is present in the central portion of the amino-terminal domain. Likewise, the allelic polymorphism of the DC beta chains occurs preferentially in the amino-terminal domain, where three minor clusters of replacements can be discerned. The non-random distribution of the variability of DC alpha and beta chains may be due to phenotypic selection against replacement substitutions in the second domains of the polypeptides.

Isolation and identification of a cDNA clone coding for an HLA-DR transplantation antigen alpha-chain

Membrane-bound mRNA was isolated from Raji cells and enriched for message coding for the HLA-DR transplantation antigen alpha-chain by sucrose gradient centrifugation. Double-stranded cDNA was constructed from this mRNA fraction, ligated to plasmid pBR322, and cloned into Escherichia coli. By hybrid selection, a plasmid, pDR-alpha-1, able to hybridize with mRNA coding for the HLA-DR alpha-chain was identified. From the nucleotide sequence of one end of the insert an amino acid sequence was predicted which is identical to part of the amino-terminal sequence of an HLA-DR alpha-chain preparation isolated from Raji cells. This clearly shows that pDR-alpha-1 carries almost the complete message for an HLD-DR alpha-chain. From the nucleotide sequence of this plasmid it will be possible to predict the primary structure of an HLA-DR alpha-chain.

Alpha chain of HLA-DR transplantation antigens is a member of the same protein superfamily as the immunoglobulins

Four cDNA clones, pDR-alpha-1, pDR-alpha-2, pDR-alpha-3 and pDR-alpha-4, corresponding to the alpha chain of HLA-DR antigens, have been sequenced. Restriction maps and sequences suggest that all clones are identical apart from a single-base substitution present in pDR-alpha-1. Amino acid sequence data, together with the nucleotide sequence data, allowed the complete amino acid sequence to be predicted. The alpha chain is composed of 229 amino acids, of which 191 are exposed on the outside of the plasma membrane. The membrane-embedded portion of the chain consists of 23 hydrophobic amino acids. The succeeding 15 amino acids form the cytoplasmically localized hydrophilic tail. The extracellular portion, with carbohydrate moieties linked to Asn78 and Asn118, seems to be organized into two domains. The second domain, which contains the only disulfide bond of the alpha chain, displays amino acid sequence homology to immunoglobulin constant regions, to the second domain of the beta chain of a class II antigen, to the third domain of heavy chains of class I antigens and to beta 2-microglobulin. Thus the subunits of immunoglobulins, class I antigens and class II antigens are related evolutionarily.

Isolation and identification of a cDNA clone corresponding to an HLA-DR antigen beta chain

The HLA-D locus in the major histocompatibility complex controls the expression of the genetically polymorphic HLA-DR antigens. mRNA coding for the beta chains of these antigens was partially purified from the human lymphoblastoid cell line Raji. The mRNA was copied into double-stranded cDNA and cloned in Escherichia coli. One clone, pDR-beta-1, obtained by hybrid selection, carries a 1070-base-pair insert comprising all of the coding region except the signal sequence and a substantial portion of the untranslated region. To identify pDR-beta-1, highly purified HLA-DR antigen beta chains derived from Raji cells were subjected to NH2-terminal amino acid sequence determination. This sequence displayed extensive homology with that deduced from the nucleotide sequence at the 5' end of the pDR-beta-1 coding region. Taken together, the amino acid and nucleotide sequences strongly argue in favor of Raji cells containing at least two beta-chain loci.

Alexander's disease: case report including histopathological and electron microscopic features

We report a case of Alexander's disease in a black South African boy of 9 years. The child presented with a grossly abnormal stooped posture, generalised weakness, and slurred nasal speech. Computerised tomography revealed diffuse low radio-density confined to the white matter, and enlarged ventricles. Cerebral biopsy confirmed the diagnosis. The histopathological and electron microscopic features are essentially the same as those described in previous reports. We note the presence of dense clumps of material within some of the Rosenthal fibres, and can find no reference in the literature describing this. Sural nerve biopsy was normal.

Crural hypertrophy associated with centronuclear myopathy

A case of centronuclear myopathy of adult onset with striking hypertrophy of lower limb muscles in a black South African man is described with details of the light microscopic, histochemical, and ultrastructural features. The association of hypertrophied muscles with centronuclear myopathy has not to our knowledge been reported previously and it is felt that this may be a variant of the condition.

The metabolism of phenobarbitone, phenytoin and antipyrine in Black patients

The half-lives of phenytoin, phenobarbitone and antipyrine were studied in adult Black patients to attempt to ascertain the cause of low phenytoin concentrations previously found in Black epileptics. The following half-life values were observed: antipyrine 5,7 +/- 1,9 hours, phenytoin 15,9 +/- 7,9 hours, phenobarbitone 63,0 +/- 18,2 hours, and phenytoin after 1 month of phenobarbitone therapy 31,5 +/- 11,9 hours. No explanation was obtained for the low phenytoin levels previously observed.

Serum levels of anticonvulsants and haematological sequelae in black epileptics

Serum levels of phenytoin and phenobarbitone were studied in a group of Black adult epileptics. Therapeutically satisfactory levels of phenytoin were observed in only 11,3% of patients, and of phenobarbitone, in 63,9%. An overall non-compliance rate of about 50% was noted. The possible reasons for this are discussed. Folate deficiency was not a major problem in this group of patients.

Polymyositis as a cause of malabsorption. A case report

We report on a patient with polymyositis which caused a malabsorption syndrome. The radiological findings included marked dilatation of the oesophagus and small intestine. The malabsorption syndrome appears to arise from bacterial overgrowth associated with intestinal stasis. The literature is reviewed. Polymyositis or dermatomyositis, like scleroderma, may involve the small bowel and cause the malabsorption syndrome.