One-minute sit-to-stand test as a quick functional test for people with COPD in general practice.

Assessing changes in functional exercise capacity is highly relevant in the treatment of people with Chronic Obstructive Pulmonary Disease (COPD), as lung function is often static. In Denmark, most people with COPD are followed in general practice where traditional functional tests, like six-minute walk test, require too much time and space. Therefore, there is an urgent need for a quick functional exercise capacity test that can be performed in a limited setting, such as general practice. This study aimed to identify a quick test to measure functional exercise capacity in people with COPD and identify which factors could affect the implementation of such a test in general practice. A mixed method feasibility study composed of a literature review and qualitative interviews was used. Quick functional tests for people with COPD were identified and evaluated through the COSMIN methodology. For the interviews, 64 general practices were included, and 50 staff members and 14 general practitioners (GPs) participated in the interviews. Responses were categorized and thematically analyzed. The 1 min sit-to-stand-test (1 M STST) was found suitable for a general practice setting. The COSMIN methodology rated it "sufficient" in reliability (ICC 0.90-0.99), measurement error (MID 2.5-3), construct validity and responsiveness (AUC 0.72), and found a moderate to strong correlation in criterion validity (r = 0.4-0.75). Several GPs wished for a quick functional test and emphasized evidence, information, and limitations as essential when deciding on implementation. Other factors identified included time, other tests, and economy. 1 M STST is a valid test to assess functional exercise capacity in people with COPD. The test is quick and can easily be performed in a standard consultation, and several GPs wished for such a test.

A healthy individual with a homozygous PTCH2 frameshift variant: Are variants of PTCH2 associated with nevoid basal cell carcinoma syndrome?

Variants in PTCH2 have been described to be associated with Nevoid Basal Cell Carcinoma Syndrome (NBCCS). We report a family with a healthy female who is homozygous for a frameshift variant, c.269delG, p.(Gly90Alafs*4), in PTCH2 and her heterozygous daughter. The variant predicts a frameshift and a premature stop codon. A summary of reported heterozygous individuals with germline PTCH2 variants along with the existence of a healthy homozygous individual question whether variants in PTCH2 are associated with NBCCS.

Natural disease course and genotype-phenotype correlations in Complex I deficiency caused by nuclear gene defects: what we learned from 130 cases.

Mitochondrial complex I is the largest multi-protein enzyme complex of the oxidative phosphorylation system. Seven subunits of this complex are encoded by the mitochondrial and the remainder by the nuclear genome. We review the natural disease course and signs and symptoms of 130 patients (four new cases and 126 from literature) with mutations in nuclear genes encoding structural complex I proteins or those involved in its assembly. Complex I deficiency caused by a nuclear gene defect is usually a non-dysmorphic syndrome, characterized by severe multi-system organ involvement and a poor prognosis. Age at presentation may vary, but is generally within the first year of life. The most prevalent symptoms include hypotonia, nystagmus, respiratory abnormalities, pyramidal signs, dystonia, psychomotor retardation or regression, failure to thrive, and feeding problems. Characteristic symptoms include brainstem involvement, optic atrophy and Leigh syndrome on MRI, either or not in combination with internal organ involvement and lactic acidemia. Virtually all children ultimately develop Leigh syndrome or leukoencephalopathy. Twenty-five percent of the patients died before the age of six months, more than half before the age of two and 75 % before the age of ten years. Some patients showed recovery of certain skills or are still alive in their thirties . No clinical, biochemical, or genetic parameters indicating longer survival were found. No clear genotype-phenotype correlations were observed, however defects in some genes seem to be associated with a better or poorer prognosis, cardiomyopathy, Leigh syndrome or brainstem lesions.

Mutations in PCDH21 cause autosomal recessive cone-rod dystrophy.

BACKGROUND: Cone-rod dystrophy is a retinal dystrophy with early loss of cone photoreceptors and a parallel or subsequent loss of rod photoreceptors. It may be syndromic, but most forms are non-syndromic with autosomal dominant, autosomal recessive or X-linked recessive inheritance. METHODS AND RESULTS: We identified a small consanguineous family with six patients with cone-rod dystrophy from the Faroe Islands. Homozygosity mapping revealed a single homozygous locus of 4.2 Mb on chromosome 10q23.1-q23.2, encompassing 11 genes. All patients were homozygous for a 1-bp duplication in PCDH21, c.524dupA, which results in a frameshift and a premature stop codon (p.Q175QfsX47). CONCLUSION: To our knowledge, this is the first report of mutations in PCDH21 as a cause of human disease. PCDH21 is highly expressed in the retinal photoreceptor cells. It encodes protocadherin 21, which belongs to the cadherin superfamily of large cell surface proteins characterised by a variable number of extracellular cadherin domains. A PCDH21 knockout mouse model has previously shown loss of photoreceptor cells and abnormal cone and rod function, similar to the findings in the patients.

The severity of phenotype linked to SUCLG1 mutations could be correlated with residual amount of SUCLG1 protein.

BACKGROUND: Succinate-CoA ligase deficiency is responsible for encephalomyopathy with mitochondrial DNA depletion and mild methylmalonic aciduria. Mutations in SUCLA2, the gene encoding a ß subunit of succinate-CoA ligase, have been reported in 17 patients until now. Mutations in SUCLG1, encoding the α subunit of the enzyme, have been described in two pedigrees only. METHODS AND FINDINGS: In this study, two unrelated patients harbouring three novel pathogenic mutations in SUCLG1 were reported. The first patient had a severe disease at birth. He was compound heterozygous for a missense mutation (p.Pro170Arg) and a c.97+3G>C mutation, which leads to the complete skipping of exon 1 in a minigene expression system. The involvement of SUCLG1 was confirmed by western blot analysis, which showed absence of SUCLG1 protein in fibroblasts. The second patient has a milder phenotype, similar to that of patients with SUCLA2 mutations, and is still alive at 12 years of age. Western blot analysis showed some residual SUCLG1 protein in patient's fibroblasts. CONCLUSIONS: Our results suggest that SUCLG1 mutations that lead to complete absence of SUCLG1 protein are responsible for a very severe disorder with antenatal manifestations, whereas a SUCLA2-like phenotype is found in patients with residual SUCLG1 protein. Furthermore, it is shown that in the absence of SUCLG1 protein, no SUCLA2 protein is found in fibroblasts by western blot analysis. This result is consistent with a degradation of SUCLA2 when its heterodimer partner, SUCLG1, is absent.

Identification of a novel locus for a USH3 like syndrome combined with congenital cataract.

Usher syndrome (USH) is the most common genetic disease that causes both deafness and blindness. USH is divided into three types, USH1, USH2 and USH3, depending on the age of onset, the course of the disease, and on the degree of vestibular dysfunction. By homozygosity mapping of a consanguineous Danish family of Dutch descent, we have identified a novel locus for a rare USH3-like syndrome. The affected family members have a unique association of retinitis pigmentosa, progressive hearing impairment, vestibular dysfunction, and congenital cataract. The phenotype is similar, but not identical to that of USH3 patients, as congenital cataract has not been reported for USH3. By homozygosity mapping, we identified a 7.3 Mb locus on chromosome 15q22.2-23 with a maximum multipoint LOD score of 2.0. The locus partially overlaps with the USH1 locus, USH1H, a novel unnamed USH2 locus, and the non-syndromic deafness locus DFNB48.

Four novel PDHA1 mutations in pyruvate dehydrogenase deficiency.

The pyruvate dehydrogenase (PDH) complex is a mitochondrial multienzyme that catalyses the irreversible oxidative decarboxylation of pyruvate to acetyl-CoA. We report four novel PDHA1 mutations in patients with pyruvate dehydrogenase deficiency. Analysis of PDH activity showed decreased activity in fibroblasts from all four patients, around 16-52% of mean control, similar to what has been found in previous studies. Two of the mutations were missense mutations: c.616G>A (p.Glu206Lys) and c.457A>G (p.Met153Val), one was a 3 bp in-frame deletion: c.429_431delAGG (p.Gly143del), and one was a 65 bp duplication: c.900-6_958dup65. cDNA analysis of the 65 bp duplication showed a small amount of normal transcript in addition to the transcript corresponding to the duplication. The small amount of normal transcript likely explains the survival of the patient, who was a boy. The duplication and one of the missense mutations were associated with decreased amounts of E(1)α And E(1)ß protein on western blot analysis, whereas the other two mutations were associated with normal amounts. This study adds four novel mutations to the around 90 reported mutations in PDHA1 (HGMD PDHA1 mutation database). The phenotypes of patients with PDH deficiency have been divided into three groups: a neonatal form with severe lactic acidosis, a form observed only in males and characterized by episodes of ataxia with relapses associated with hyperlactataemia, and an infantile form with hypotonia, lethargy, onset of seizures or dystonia, psychomotor retardation, in some cases Leigh-like lesions and mild to moderate hyperlactataemia. The four patients reported here all belong to the latter group, which is the largest.

Disorders caused by deficiency of succinate-CoA ligase.

Succinate-CoA ligase catalyses the reversible conversion of succinyl-CoA and ADP or GDP to succinate and ATP or GTP. It is a mitochondrial matrix enzyme and at least the ADP-forming enzyme is part of the Krebs cycle. The substrate specificity is determined by the beta subunit of succinate-CoA ligase, which is encoded by either SUCLA2 or SUCLG2. In patients with severe hypotonia, deafness and Leigh-like syndrome, mutations have been found in SUCLA2. Mutations have also been reported in SUCLG1, which encodes the alpha subunit found in both enzymes, in patients with severe infantile acidosis and lactic aciduria. Elevated methylmalonate and methylcitrate and severe mtDNA depletion were found in both disorders. The mtDNA depletion may be explained by the interaction of succinate-CoA ligase with nucleoside diphosphate kinase, which is involved in mitochondrial nucleotide metabolism.

Attitudes of general dental practitioners in Europe to the microbial risk associated with dental unit water systems.

UNLABELLED: Dental Unit Water Systems (DUWS) are used in dental practices to provide water for cooling of dental equipment and irrigation of the oral cavity. However, they have been demonstrated to be contaminated with micro-organisms. There are currently no European Union (EU) Commission guidelines for the microbial quality of water discharged by DUWS. This study was part of an EU research programme to investigate the microbial contamination of DUWS in general dental practice (GDP) in the UK, Denmark, Germany, The Netherlands, Ireland, Greece and Spain. OBJECTIVE: To undertake a questionnaire survey on the type of DUWS in use and determine the attitude of GDPs to the risk of microbial infection from DUWS. MATERIALS AND METHODS: The questionnaire was written and translated into the language of each country before being posted to each participating dentist. Dentists were asked to complete the questionnaire survey and return it by post. RESULTS AND CONCLUSIONS: The major findings were that the majority of dentists did not clean, disinfect or determine the microbial load of their DUWS, and that dentists would welcome regular monitoring and advice on maintaining their DUWS; the introduction of guidelines; and recommendations on controlling the microbial load of DUWS.

Comparison of the efficacies of disinfectants to control microbial contamination in dental unit water systems in general dental practices across the European Union.

Water delivered by dental unit water systems (DUWS) in general dental practices can harbor high numbers of bacteria, including opportunistic pathogens. Biofilms on tubing within DUWS provide a reservoir for microorganisms and should be controlled. This study compared disinfection products for their ability to meet the American Dental Association's guideline of <200 CFU x ml(-1) for DUWS water. Alpron, BioBlue, Dentosept, Oxygenal, Sanosil, Sterilex Ultra, and Ster4Spray were tested in DUWS (n = 134) in Denmark, Germany, Greece, Ireland, The Netherlands, Spain, and the United Kingdom. Weekly water samples were tested for total viable counts (TVCs) on yeast extract agar, and, where possible, the effects of products on established biofilm (TVCs) were measured. A 4- to 5-week baseline measurement period was followed by 6 to 8 weeks of disinfection (intermittent or continuous product application). DUWS water TVCs before disinfection ranged from 0 to 5.41 log CFU x ml(-1). Disinfectants achieved reductions in the median water TVC ranging from 0.69 (Ster4Spray) to 3.11 (Dentosept) log CFU x ml(-1), although occasional high values (up to 4.88 log CFU x ml(-1)) occurred with all products. Before treatment, 64% of all baseline samples exceeded American Dental Association guidelines, compared to only 17% following commencement of treatment; where tested, biofilm TVCs were reduced to below detectable levels. The antimicrobial efficacies of products varied (e.g., 91% of water samples from DUWS treated with Dentosept or Oxygenal met American Dental Association guidelines, compared to 60% of those treated with Ster4Spray). Overall, the continuously applied products performed better than those applied intermittently. The most effective products were Dentosept and Oxygenal, although Dentosept gave the most consistent and sustained antimicrobial effect over time.

POLG mutations in Alpers syndrome.

Described are six patients with Alpers syndrome from four unrelated families. Affected individuals harbored the following combinations of POLG mutations: 1) A467T/W1020X, 2) W748S-E1143G/G848S, 3) A467T/A467T, and 4) A467T/G848S. Homozygosity for the A467T allele in one patient was associated with a later age at onset. Mitochondrial respiratory chain studies in skeletal muscle were normal in each case. Nine combinations of mutant POLG alleles that cause Alpers syndrome are summarized.

Impaired energy metabolism and abnormal muscle histology in mut- methylmalonic aciduria.

The authors report a 27-year-old man with B12-responsive mut- methylmalonic aciduria associated with pure muscle symptoms. Two mutations were found in the methylmalonyl-CoA mutase gene. An exercise test showed a reduced maximal workload and reduced oxygen uptake, and a muscle biopsy showed subsarcolemmal accumulation of mitochondria and normal respiratory chain enzyme activities. These findings may be caused by inhibition of mitochondrial energy metabolism by methylmalonate or its metabolites.

Microbiological evaluation of dental unit water systems in general dental practice in Europe.

A range of opportunistic pathogens have been associated with dental unit water systems (DUWS), particularly in the biofilms that can line the tubing. This study therefore aimed to assess the microbiology of DUWS and biofilms in general dental practices across seven European countries, including the United Kingdom (UK), Ireland (IRL), Greece (GR), Spain (ES), Germany (D), Denmark (DK) and the Netherlands (NL). Water supplied by 51% of 237 dental unit water lines exceeded current American Dental Association recommendations of < or = 200 colony-forming units (CFU) ml(-1). Microbiological loading of the source waters was between 0 (Denmark, the Netherlands and Spain) and 4.67 (IRL) log CFU ml(-1); water line samples from the DUWS ranged from 1.52 (ES) to 2.79 (GR) log CFU ml(-1); and biofilm counts ranged from 1.49 (GR) to 3.22 (DK) log CFU.cm(-2). Opportunistic pathogens such as legionellae (DK and ES), including Legionella pneumophila SG1 (DK and GR), and Mycobacterium spp. (DK, NL, GR, D and ES) were recovered occasionally. Presumptive oral streptococci (ES and NL), oral anaerobes (GR), Candida spp. (UK, NL and ES) and blood (GR and IRL) were detected at relatively low frequencies, but their presence indicated a failure of the 3-in-1 antiretraction valve, leading to back siphonage of oral fluids into the water and biofilm phase. These findings confirm that a substantial proportion of DUWS have high levels of microbial contamination, irrespective of country, type of equipment and source water. The study emphasizes the need for effective mechanisms to reduce the microbial burden within DUWS, and highlights the risk of occupational exposure and cross-infection in general dental practice.

Gc globulin (vitamin D-binding protein) levels: an inhibition ELISA assay for determination of the total concentration of Gc globulin in plasma and serum.

Gc globulin, also called vitamin D-binding protein, is a plasma protein involved in the actin-scavenger system. In this study, the total Gc globulin concentration in serum or plasma samples was determined using a new, fast, solid-phase inhibition assay. Included in the study were 228 healthy volunteers (131 M, 97 F), 22 pregnant women, 90 cancer patients and 9 patients with chronic liver disease. Moreover, the degree of complexing with actin was determined in selected samples using crossed immunoelectrophoresis. The Gc globulin level in healthy controls was in the range 176-623 mg/L, showing no age dependency. The median level was found to be significantly higher in women than in men. Gc globulin concentrations were raised during pregnancy, showing a median value of 541 mg/L in the first trimester, and slightly raised to 574 mg/L in the second trimester. Cancer patients showed no changes in Gc globulin level, and there was no sign of increased amounts of complexing with actin. Chronic liver patients showed increased levels of Gc globulin following transplantation, but no signs of complexing with actin. This new solid-phase inhibition assay is fast, it is a good complement to the existing quantification methods, and it is especially suitable for determination of the Gc globulin status in acute liver patients before and during treatment.

Sporadic hemiplegic migraine is an aetiologically heterogeneous disorder.

In order to better understand sporadic hemiplegic migraine (SHM) and particularly its relation to familial hemiplegic migraine (FHM), migraine without aura (MO) and typical migraine with aura (typical MA), we investigated the occurrence of MO and typical MA among probands with SHM and their first-degree relatives. The pattern of familial aggregation of MO and typical MA was assessed by population relative risk calculations. A total of 105 SHM probands and 483 first-degree relatives were identified in the Danish population. Compared with the general population, SHM probands had no increased risk of MO, but a highly increased risk of typical MA. First-degree relatives of all SHM probands had an increased risk of both MO and typical MA, whereas first-degree relatives of probands with exclusively SHM had no increased risk of MO but an increased risk of typical MA. Our data suggest that SHM is a genetically heterogeneous disorder.

The A1555G mtDNA mutation in Danish hearing-impaired patients: frequency and clinical signs.

The A1555G mutation of the mtDNA is associated with both aminoglycoside-induced and non-syndromic hearing loss. The A1555G is relatively frequent in the Spanish and some Asian populations, but has only been reported rarely in other populations, possibly because of ascertainment bias. We studied 85 Danish patients with varying degrees of hearing impairment and found two patients with the A1555G mutation (2.4%). Neither had received aminoglycosides. Our study indicates that the mutation might not be uncommon in Danish patients with hearing impairment.

An epidemiological survey of hemiplegic migraine.

The objective of the present study was to use systematic nation-wide case-finding methods to establish the prevalence and sex ratio of hemiplegic migraine (HM) in the entire Danish population of 5.2 million inhabitants. Affected patients were identified from three different recruitment sources: the National Patient Register, case records from private practising neurologists and advertisements. Based on the observed number of affected patients from each case-finding method, it was attempted to estimate the total number of affected patients by means of the statistical method known as capture-recapture. Two hundred and ninety-one affected patients were identified; 147 were familial HM from 44 different families, 105 were sporadic HM and 39 were unclassifiable HM. The HM sex ratio (M:F) was 1:3. Based on the identified number of affected patients the prevalence of HM at the end of 1999 was estimated to be 0.01% in Denmark, where the familial and sporadic form were equally frequent.

Effect of vitamin A administered at Expanded Program on Immunization contacts on antibody response to oral polio vaccine.

OBJECTIVE: Vitamin A supplementation to mothers in the postpartum period and to their infants at routine immunization contacts is being considered to reduce vitamin A deficiency in infancy. This study was conducted to determine the impact of maternal and infant vitamin A supplementation on antibody response to oral polio vaccine (OPV). DESIGN: Randomized, double blind, placebo-controlled trial. INTERVENTIONS: Mothers in the intervention group received 60 mg retinol equivalent (RE) vitamin A 3-4 weeks after delivery and their infants 7.5 mg RE with each OPV dose at 6, 10 and 14 weeks of age. The control group mothers and their infants received a placebo at each of these contacts. MAIN OUTCOMES: Geometric mean (GM) titer of neutralizing antibodies and proportion of children with protective titer to the three polioviruses at 26 weeks of age. RESULTS: Vitamin A supplementation increased the proportion of infants with protective antibody titer against poliovirus type 1 (relative risk (RR) 1.15, 95% confidence interval (CI) 1.03-1.28) and the GM antibody titer (ratio of GM 1.55, 95% CI 1.03-2.31) following immunization. The proportion of infants with protective antibody titer against poliovirus type 2 (RR 0.99, 95% CI 0.94-1.05) or type 3 (RR 1.05, 95% CI 0.96-1.15) was not significantly different in vitamin A and placebo groups. The GM antibody titer for poliovirus type 2 (ratio of GM 0.99, 95% CI 0.64-1.54) or poliovirus type 3 (ratio of GM 1.10, 95% CI 0.69-1.75) also did not differ across groups. CONCLUSIONS: Vitamin A given to the mothers in the postpartum period and their infants with OPV did not interfere with the antibody response to any of the three polioviruses and enhanced the response to poliovirus type 1.

[Molecular genetic findings in migraine]. / Molekylaergenetiske fund ved migraene.

This review focuses on the different molecular genetic findings in migraine. Familial hemiplegic migraine (FHM) is a rare subtype of migraine with aura, which is inherited as an autosomal dominant. Half the cases of FHM are caused by point mutations in the CACNA1A gene on the short arm of chromosome 19 (19p). The gene encodes a calcium ion channel. Other mutation types cause episodic ataxia 2 (EA-2). Expansions of the CAG repeat in the 3' end bring about spinocerebellar ataxia 6 (SCA 6). Some families with FHM link to loci on the long arm of chromosome 1 (1q). The genes have not yet been identified. Some families neither link to 1q nor to 19p. Population-based family and twin studies have shown that migraine both with and without aura have a multifactorial inheritance. The CACNA1A gene may be of importance for ordinary forms of migraine in a few families. Mutations in genes on the X chromosome, dopamine receptor genes, and the ACE gene appear to be involved in migraine in a few families, whereas genes for nitric oxide synthase, serotonin receptors, and mitochondrial DNA do not seem to be involved. The positive associations have not been reproduced in other studies and therefore they should be interpreted with care. It is to be hoped that in the next few years much more will be known about the molecular genetic mechanisms of migraine with and without aura. FHM is an ion channel disorder, and many factors suggest that migraine is also an ion channel disorder, which is consistent with the paroxysmal nature of the illness.