RESUMEN
OBJECTIVES: The objective of this study is to increase understanding of knowledge, attitudes, and preventative practices regarding ischemic heart disease (IHD) in sub-Saharan Africa in order to develop patient-centered interventions to improve care and outcomes. STUDY DESIGN: This is a prospective observational study. METHODS: Adult patients presenting with chest pain or shortness of breath to an emergency department in northern Tanzania were enrolled. A questionnaire was adapted from existing knowledge attitude and practice surveys regarding cardiovascular disease and the WHO STEPS instrument. Individual five-year risk of cardiovascular event was determined by validated models based on age, sex, systolic blood pressure, body mass index, diabetes, and smoking status. An IHD knowledge score was calculated by giving one point for each correct response to the knowledge-related items, with a maximum score of 10. Associations between IHD knowledge and patient characteristics were assessed by Welch's t-test. RESULTS: A total of 349 patients were enrolled, with median interquartile range (IQR) age 60 (45, 72) years. Of participants, 259 (74.2%) had hypertension, and 228 (65.3%) had greater than 10% five-year risk of cardiovascular event. The mean (SD) knowledge score was 4.8 (3.3). The majority of respondents (224, 64.2%) recognized obesity as a risk factor for heart attack, while a minority (34, 9.7%) knew that a daily aspirin could reduce the risk of cardiovascular event. Greater IHD knowledge was associated with younger age (P = 0.045) and higher levels of education (P < 0.001) but not higher risk of cardiovascular disease (P = 0.123). Most respondents expressed a willingness to diet to improve their health (322, 92.3%) and a preference for treatment from a physician rather than a traditional healer for a heart attack (321, 92.0%). A minority of patients reported exercising regularly (88, 25.2%) or seeing a doctor routinely for checkups (100, 28.7%). CONCLUSIONS: High-risk emergency department patients in northern Tanzania have moderate knowledge regarding IHD but do not consistently engage in healthy preventive practices. Patient-centered interventions are needed to improve IHD knowledge and practices in high-risk populations.
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Servicio de Urgencia en Hospital , Conocimientos, Actitudes y Práctica en Salud , Isquemia Miocárdica/prevención & control , Pacientes/psicología , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pacientes/estadística & datos numéricos , Estudios Prospectivos , Factores de Riesgo , Encuestas y Cuestionarios , TanzaníaRESUMEN
Several species of Leishmania are responsible for leishmaniases in Thailand, although little is known about their transmission. Sergentomyia gemmea has been suspected several times to transmit Leishmania martiniquensis. Some captures carried out in Thailand and Lao People's Democratic Republic have emphasized the scarcity of Se. gemmea, comprising only 1% of the collected females. The sequencing of cytochrome B mtDNA of our specimens showed that our specimens are not grouped with other Se. gemmea previously deposited in GenBank. The latter are grouped with some Se. khawi and Se. hivernus that we processed in the present study. We suspect misidentifications and propose focusing on the most useful characters for identification of Se. gemmea based on the examination of type-specimens. The examination of the ascoids exhibiting anterior spurs is the most important one. However, we also describe Se. raynali n. sp. exhibiting comparable spurs but differing from Se. gemmea by its original cibarium. Finally, the vectorial role of Se. gemmea appears very questionable in the absence of new evidence.
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Insectos Vectores/clasificación , Psychodidae/clasificación , Animales , Citocromos b/análisis , ADN Mitocondrial/análisis , Femenino , Proteínas de Insectos/análisis , Insectos Vectores/anatomía & histología , Insectos Vectores/genética , Laos , Masculino , Psychodidae/anatomía & histología , Psychodidae/genética , Análisis de Secuencia de ADN , TailandiaRESUMEN
OBJECTIVE: To identify epidemiological and pathophysiological factors, and treatment strategies, in external auditory canal cholesteatoma and benign necrotising otitis externa. METHODS: A retrospective case study was conducted of patients suffering from external auditory canal cholesteatoma and benign necrotising otitis externa admitted to tertiary hospitals, in the Capital Region of Denmark, over a five-year period. RESULTS: Eighty-three patients (95 ears) with external auditory canal cholesteatoma or benign necrotising otitis externa were identified. A minimum incidence rate of 0.97 per 100 000 inhabitants per year was demonstrated. Sixty-eight per cent of cases had a history of smoking. Most lesions (74 per cent) were localised in the floor of the ear canal. Treatment time was 3.2 months for patients who had surgery and 6.0 months for those who received conservative treatment. CONCLUSION: It is suggested that external auditory canal cholesteatoma and benign necrotising otitis externa are in fact the same disease, and therefore the diagnosis of external auditory canal cholesteatoma should be changed to benign necrotising otitis externa. Microangiopathy has a leading role in the aetiology. Surgery should be conducted in most cases.
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Colesteatoma/epidemiología , Conducto Auditivo Externo/patología , Enfermedades del Oído/epidemiología , Otitis Externa/epidemiología , Fumar/epidemiología , Administración Tópica , Adulto , Anciano , Antibacterianos/uso terapéutico , Antiinflamatorios/uso terapéutico , Colesteatoma/fisiopatología , Colesteatoma/terapia , Tratamiento Conservador , Legrado , Dinamarca/epidemiología , Enfermedades del Oído/fisiopatología , Enfermedades del Oído/terapia , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Necrosis , Otitis Externa/fisiopatología , Otitis Externa/terapia , Procedimientos Quirúrgicos Otológicos , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la EnfermedadRESUMEN
Identification of fetal kidney anomalies invites questions about underlying causes and recurrence risk in future pregnancies. We therefore investigated the diagnostic yield of next-generation sequencing in fetuses with bilateral kidney anomalies and the correlation between disrupted genes and fetal phenotypes. Fetuses with bilateral kidney anomalies were screened using an in-house-designed kidney-gene panel. In families where candidate variants were not identified, whole-exome sequencing was performed. Genes uncovered by this analysis were added to our kidney panel. We identified likely deleterious variants in 11 of 56 (20%) families. The kidney-gene analysis revealed likely deleterious variants in known kidney developmental genes in 6 fetuses and TMEM67 variants in 2 unrelated fetuses. Kidney histology was similar in the latter 2 fetuses-presenting a distinct prenatal form of nephronophthisis. Exome sequencing identified ROBO1 variants in one family and a GREB1L variant in another family. GREB1L and ROBO1 were added to our kidney-gene panel and additional variants were identified. Next-generation sequencing substantially contributes to identifying causes of fetal kidney anomalies. Genetic causes may be supported by histological examination of the kidneys. This is the first time that SLIT-ROBO signaling is implicated in human bilateral kidney agenesis.
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Enfermedades Renales/genética , Proteínas de Neoplasias/genética , Proteínas del Tejido Nervioso/genética , Diagnóstico Prenatal , Receptores Inmunológicos/genética , Autopsia , Análisis Mutacional de ADN , Femenino , Feto , Predisposición Genética a la Enfermedad , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Enfermedades Renales/fisiopatología , Masculino , Proteínas de la Membrana/genética , Mutación/genética , Secuenciación del Exoma , Proteínas RoundaboutRESUMEN
The Danish Huntington's Disease Registry (DHR) is a nationwide family registry comprising 14 245 individuals from 445 Huntington's disease (HD) families of which the largest family includes 845 individuals in 8 generations. 1136 DNA and/or blood samples and 18 fibroblast cultures are stored in a local biobank. The birthplace of the oldest HD carrier in each of the 261 families of Danish origin was unevenly distributed across Denmark with a high number of families in the middle part of the peninsula Jutland and in Copenhagen, the capital. The prevalence of HD in Denmark was calculated to be 5-8:100 000. 1451 individuals in the DHR had the size of the HTT CAG repeat determined of which 975 had 36 CAG repeats or more (mean ± SD: 43,5 ± 4,8). Two unrelated individuals were compound heterozygous for alleles ≥36 CAGs, and 60 individuals from 34 independent families carried an intermediate allele.
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Enfermedad de Huntington/epidemiología , Factores de Edad , Alelos , Bancos de Muestras Biológicas , Dinamarca/epidemiología , Familia , Femenino , Geografía Médica , Humanos , Proteína Huntingtina/genética , Enfermedad de Huntington/diagnóstico , Enfermedad de Huntington/genética , Masculino , Sistema de Registros , Expansión de Repetición de Trinucleótido , Repeticiones de TrinucleótidosAsunto(s)
Atrofia/genética , Proteínas de Homeodominio/genética , Degeneración Macular/genética , Enfermedades del Nervio Óptico/genética , Transactivadores/genética , Adolescente , Atrofia/patología , Diferenciación Celular/genética , Niño , Preescolar , Femenino , Homocigoto , Humanos , Degeneración Macular/patología , Masculino , Mutación , Enfermedades del Nervio Óptico/patología , Células Ganglionares de la Retina/patologíaRESUMEN
Klinefelter syndrome (KS, 47,XXY) is associated with increased psychiatric morbidity and cognitive disabilities, although the neuropsychological phenotype shows great variability. Androgen receptor polymorphism (CAG repeat length), skewed X-chromosome inactivation and parent-of-origin of the extra X-chromosome have been suggested to influence cognitive function and psychological traits. These issues have not been clarified for KS patients. We studied X-chromosome inactivation pattern, CAG repeat length and parent-of-origin in relation to educational and cohabitation status, personality and autism traits, psychological distress, cognitive function and brain volumes in 73 KS patients and 73 controls. Grey matter (GM) volume of left insula was significantly decreased in KS patients with skewed X-inactivation (z = 5.78) and we observed a borderline significant difference in global brain matter volume where KS patients with skewed X-chromosome inactivation tended to have smaller brains. Skewed X-inactivation, CAG repeat length and parent-of-origin were not correlated with educational and marital status, personality traits, autism traits, and psychological distress, prevalence of depression and anxiety or cognitive function. Interestingly our results regarding brain volumes indicate that X-inactivation has an influence on GM volume in left insula and might also be related to global GM volume, indicating a possible effect of X-linked genes on the development of GM volume in KS patient. Skewed X-inactivation, CAG repeat length and parent-of-origin have no impact on the neuropsychological phenotype in KS (http://www.clinicaltrials.gov (Clinical trial NCT00999310)).
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Síndrome de Klinefelter/genética , Síndrome de Klinefelter/patología , Receptores Androgénicos/genética , Adulto , Encéfalo/patología , Cromosomas Humanos X , Humanos , Síndrome de Klinefelter/psicología , Masculino , Persona de Mediana Edad , Neuropsicología , Fenotipo , Inactivación del Cromosoma XRESUMEN
BACKGROUND AND OBJECTIVES: The aim of this study was to investigate whether inflammation and regeneration are prominent in mildly affected muscles of patients with facioscapulohumeral muscular dystrophy type 1A (FSHD1A). Inflammation in muscle has been suggested by MRI studies in patients with FSHD1A. METHODS: We analysed immunohistological and histological stains of muscle biopsies from 24 patients with FSHD1A, using 10 patients with Becker muscular dystrophy (BMD) for comparison. RESULTS: Internalized nuclei were more prevalent in BMD (23.7 ± 10.8%) vs FSHD1A (6.3 ± 6.8%; P < 0.001), indicating more past regenerating fibres in BMD. Recently regenerating fibres, expressing neonatal myosin heavy chain and vimentin, did not differ significantly between patients with FSHD1A (1.1 ± 2.9%) and patients with BMD (1.8 ± 1.9%). Regeneration was not correlated with the number of KpnI restriction fragment repeats, an FSHD1A-defining genotype property within the D4Z4 locus, or overall disease severity in patients with FSHD1A. Macrophages were more prevalent in FSHD1A (0.50 ± 0.63 per mm(2) ) vs BMD (0.07 ± 0.07 per mm(2) ), whereas inflammatory T cells were equally infrequent. CONCLUSIONS: Macrophages were more prevalent in patients with FSHD1A and could be an important pathogenic mechanism for the initiation of the dystrophic process. Furthermore, regeneration was unrelated to genotype and disease severity in FSHD1A.
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Inflamación/complicaciones , Músculos/fisiopatología , Distrofia Muscular Facioescapulohumeral/complicaciones , Distrofia Muscular Facioescapulohumeral/patología , Regeneración/fisiología , Adolescente , Adulto , Anciano , Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Apoptosis , Femenino , Genotipo , Humanos , Etiquetado Corte-Fin in Situ , Masculino , Glicoproteínas de Membrana , Persona de Mediana Edad , Músculos/metabolismo , Músculos/patología , Distrofia Muscular de Duchenne/fisiopatología , Cadenas Pesadas de Miosina/metabolismo , Poli(ADP-Ribosa) Polimerasas/metabolismo , Proteínas Protozoarias , Índice de Severidad de la Enfermedad , Vimentina/metabolismo , Adulto JovenRESUMEN
The aim of this study was to investigate the endocrine function and its association to number of CTG repeats in patients with myotonic dystrophy type 1 (DM1). Concentration of various hormones and metabolites in venous blood was used to assess the endocrine function in 97 patients with DM1. Correlation with CTG(n) expansion size was investigated with the Pearson correlation test. Eighteen percent of the DM1 patients had hyperparathyroidism with increased PTH compared with 0.5% in the background population. Of these, 16% had normocalcemia and 2% had hypercalcemia. An additional 3% had hypercalcemia without elevation of PTH; 7% had abnormal TSH values (2% subnormal and 5% elevated TSH levels); 5% of the patients had type 2 diabetes mellitus; 17% of the male DM1 patients had increased LH and low levels of plasma testosterone indicating absolute androgen insufficiency. Another 21% had increased LH, but normal testosterone levels, indicating relative insufficiency. Numbers of CTG repeats correlated directly with plasma PTH, phosphate, LH, and tended to correlate with plasma testosterone for males. This is the largest study of endocrine dysfunction in a cohort of Caucasian patients with DM1. We found that patients with DM1 have an increased risk of abnormal endocrine function, particularly calcium metabolism disorders. However, the endocrine dysfunction appears not to be of clinical significance in all of the cases. Finally, we found correlations between CTG(n) expansion size and plasma PTH, phosphate, and testosterone, and neck flexion strength.
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Enfermedades del Sistema Endocrino/diagnóstico , Enfermedades del Sistema Endocrino/etiología , Distrofia Miotónica/complicaciones , Repeticiones de Trinucleótidos/genética , Adolescente , Adulto , Calcio/metabolismo , Catarata/etiología , Análisis Mutacional de ADN , Diabetes Insípida/etiología , Enfermedades del Sistema Endocrino/genética , Ensayo de Inmunoadsorción Enzimática , Femenino , Hormonas/sangre , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/patología , Distrofia Miotónica/genética , Hormona Paratiroidea/genética , Factores Sexuales , Adulto JovenRESUMEN
The phenotypic variation of Klinefelter syndrome (KS) is wide and may by caused by various genetic and epigenetic effects. Skewed inactivation of the supra-numerical X chromosome and polymorphism in the androgen receptor (AR) have been suggested as plausible causes. We wanted to describe X-chromosome inactivation patterns and the AR polymorphism and correlate these to clinical findings in KS in a cross-sectional study. To that end, we studied 70 KS patients enrolled from fertility clinics and endocrine clinics and 70 age-matched control subjects. The main outcome was X-chromosome inactivation pattern (skewX), AR polymorphism (CAGn - repeat length) and correlation to anthropometrical, hormonal, metabolic and bone-related variables. Forty-six of 70 KS men were heterozygous for CAGn. The shortest and the longest alleles were equally frequent inactivated and the mean CAGn of the two alleles did not differ significantly from the CAGn from either KS men, homozygous for the CAGn, or from the control subjects (22 vs. 23 vs. 21). SkewX was found in 12 of the 46 informative KS men (26%). In KS, height and arm span correlated positively to CAGn, whereas total cholesterol and haematocrit correlated negatively to CAGn. In controls, bone mineral density at the spine and hip correlated positively with CAGn, whereas adiponectin correlated negatively with CAGn. SkewX did not correlate to any of the investigated parameters. We conclude that CAGn polymorphism in AR explain some of the phenotypic variation in KS, whereas skewed X-chromosome inactivation did not. The impact of CAGn on final height may be caused by later reactivation of the pituitary-gonadal axis.
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Síndrome de Klinefelter/genética , Regiones Promotoras Genéticas , Receptores Androgénicos/genética , Inactivación del Cromosoma X , Genotipo , Humanos , FenotipoRESUMEN
Dystrophic epidermolysis bullosa pruriginosa (DEB-Pr) (OMIM 604129) represents a distinct variant within the DEB clinical spectrum. It is characterized by intense pruritus and distinctive nodular prurigo-like and/or hypertrophic lichenoid lesions mainly localized on the arms, legs and upper shoulders. DEB-Pr is caused by either dominant (DDEB-Pr) or recessive mutations in the COL7A1 gene encoding type VII collagen (COLVII). The full spectrum of COL7A1 mutations in DEB-Pr remains elusive and the genotype-phenotype correlation is largely incomplete. Here, we report and functionally characterize a previously unrecognized translationally silent exonic COL7A1 mutation that results in skipping of exon 87 and is associated with DDEB-Pr phenotypes in several members of three apparently unrelated Danish families. A haplotype segregation study suggested a common ancestor in these kindred. Functional splicing analysis of the mutant exon by a COL7A1 minigene construct and computational prediction for splicing regulatory cis-sequences prove that the mutation alters the activity of an exonic splicing enhancer (ESE) critical for exon inclusion. These findings substantiate for the first time the involvement of an ESE mutation in the pathogenesis of DEB and have implications for genetic counselling of Danish families with DDEB.
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Colágeno Tipo VII/genética , Epidermólisis Ampollosa Distrófica/genética , Exones/genética , Mutación/genética , Empalme del ARN/genética , Adolescente , Adulto , Femenino , Efecto Fundador , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad , LinajeRESUMEN
Mutations in the FGD1 gene have been shown to cause Aarskog-Scott syndrome (AAS), or facio-digito-genital dysplasia (OMIM#305400), an X-linked disorder characterized by distinctive genital and skeletal developmental abnormalities with a broad spectrum of clinical phenotypes. To date, 20 distinct mutations have been reported, but little phenotypic data are available on patients with molecularly confirmed AAS. In the present study, we report on our experience of screening for mutations in the FGD1 gene in a cohort of 60 European patients with a clinically suspected diagnosis of AAS. We identified nine novel mutations in 11 patients (detection rate of 18.33%), including three missense mutations (p.R402Q; p.S558W; p.K748E), four truncating mutations (p.Y530X; p.R656X; c.806delC; c.1620delC), one in-frame deletion (c.2020_2022delGAG) and the first reported splice site mutation (c.1935+3A>C). A recurrent mutation (p.R656X) was detected in three independent families. We did not find any evidence for phenotype-genotype correlations between type and position of mutations and clinical features. In addition to the well-established phenotypic features of AAS, other clinical features are also reported and discussed.
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Factores de Intercambio de Guanina Nucleótido/genética , Discapacidad Intelectual/genética , Mutación , Síndrome , Anomalías Múltiples/genética , Secuencias de Aminoácidos , Huesos/anomalías , Estudios de Cohortes , Análisis Mutacional de ADN , Europa (Continente) , Genitales Masculinos/anomalías , Mutación de Línea Germinal , Humanos , Masculino , FenotipoRESUMEN
The X-linked form of Alport syndrome (AS) is caused by mutations in the COL4A5 gene encoding the alpha5 chain of type IV collagen. Most COL4A5 mutations are individual, and mutation analysis is complicated by the size of the gene and the number of exons. Larger structural rearrangements account for 10-15% of mutations. We have established a method for mutation analysis of COL4A5 based on reverse transcriptase-polymerase chain reaction analysis of mRNA from cultured skin fibroblasts and multiplex ligation-dependent probe amplification (MLPA) on genomic DNA. One advantage of using skin biopsies for the mRNA analysis is the possibility of immunohistochemical staining for the alpha5(IV) chain on skin sections to support a diagnosis of X-linked AS. A mutation was detected in all five cases included. One patient presenting with AS and diffuse leiomyomatosis was found to have a COL4A5 deletion extending into and comprising COL4A6 exons 1, 1', and 2. We have evaluated the MLPA assay on samples from 67 previously tested AS patients (45 males and 22 females) and 20 controls. We found that the combination of cDNA and MLPA analysis improves the mutation detection rate in COL4A5 and that MLPA should be the first step in genetic testing for X-linked AS.
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Colágeno Tipo IV/genética , ADN Complementario/genética , Mutación/genética , Nefritis Hereditaria/diagnóstico , Nefritis Hereditaria/genética , Células Cultivadas , Femenino , Fibroblastos/citología , Técnicas Genéticas , Humanos , Masculino , ARN Mensajero/análisis , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Eliminación de Secuencia/genética , Piel/citologíaRESUMEN
This study aimed to investigate genotype and phenotype in males affected with X-linked hypohidrotic ectodermal dysplasia (HED) and in female carriers, to analyse a possible genotype-phenotype correlation, and to analyse a possible relation between severity of the symptoms and the X-chromosome inactivation pattern in female carriers. The study group comprised 67 patients from 19 families (24 affected males and 43 female carriers). All participants had clinical signs of ectodermal dysplasia and a disease-causing EDA mutation. The EDA gene was screened for mutations by single-stranded conformational polymorphism and direct sequencing. Multiplex ligation-dependent probe amplification (MLPA) analysis was used to detect deletions/duplications in female probands. Sixteen different EDA mutations were detected in the 19 families, nine not described previously. The MLPA analysis detected a deletion of exon 1 in one female proband. No genotype-phenotype correlations were observed, and female carriers did not exhibit a skewed X-chromosome inactivation pattern. However, in two female carriers with pronounced clinical symptoms, in whom the parental origin of each allele was known, we observed that mainly the normal allele was inactivated.
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Anodoncia/genética , Displasia Ectodermal Anhidrótica Tipo 1/genética , Cromosomas Humanos X/metabolismo , Análisis Mutacional de ADN , Dinamarca , Displasia Ectodermal Anhidrótica Tipo 1/diagnóstico , Exones , Femenino , Genotipo , Humanos , Masculino , Mutación , Fenotipo , Diente/patologíaRESUMEN
OBJECTIVE: To describe the somatic development and craniofacial morphology in males affected with hypohidrotic ectodermal dysplasia (HED) and female carriers and to find clinical markers for early clinical diagnosis of possible female carriers. DESIGN: A clinical and radiographic examination of the affected males and the female carriers. SETTING AND SAMPLE POPULATION: Twenty-four affected males and 43 female carriers with a known mutation in the ED1 gene were examined in a dental clinic in either Copenhagen or Aarhus, Denmark. EXPERIMENTAL VARIABLES: Height, body mass index (BMI) and head circumference. Cephalometric analysis of the craniofacial morphology. OUTCOME MEASURE: Data on the somatic and craniofacial development in the affected males and female carriers. RESULTS: No difference was observed regarding body height in the affected males and female carriers, BMI values were lower than the mean in most affected boys and adolescence and head circumference was somewhat decreased in both groups compared to normative data. The cephalometric analysis showed a reduced maxilla length and prognathism, a normal size and shape of the mandible and a reduced sagittal jaw relationship in both HED groups. Furthermore, affected males had a retroclined nasal bone and a more anteriorly inclined maxilla. A short nose, protruding lips, reduced facial convexity and facial height, characterized the soft tissue profile of the affected males. In female carriers, the lips were significantly retruded when compared with controls. CONCLUSION: No specific somatic or cephalometric markers could be observed, in the female carrier group.
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Anodoncia/etiología , Cefalometría/estadística & datos numéricos , Displasia Ectodermal Anhidrótica Tipo 1/complicaciones , Anomalías Maxilofaciales/etiología , Cráneo/anomalías , Adolescente , Adulto , Anciano , Anodoncia/genética , Estatura , Índice de Masa Corporal , Niño , Preescolar , Displasia Ectodermal Anhidrótica Tipo 1/patología , Ectodisplasinas/genética , Femenino , Tamización de Portadores Genéticos , Humanos , Masculino , Anomalías Maxilofaciales/genética , Anomalías Maxilofaciales/patología , Persona de Mediana Edad , MutaciónRESUMEN
Autosomal recessive Parkinson's disease (PD) with early-onset may be caused by mutations in the parkin gene (PARK2). We have ascertained 87 Danish patients with an early-onset form of PD (age at onset < or =40 years, or < or =50 years if family history is positive) in a multicenter study in order to determine the frequency of PARK2 mutations. Analysis of the GTP cyclohydrolase I gene (GCH1) and the tyrosine hydroxylase gene (TH), mutated in dopa-responsive dystonia and juvenile PD, have also been included. Ten different PARK2 mutations were identified in 10 patients. Two of the patients (2.3%) were found to have homozygous or compound heterozygous mutations, and eight of the patients (9.2%) were found to be heterozygous. A mutation has been identified in 10.4% of the sporadic cases and in 15.0% of cases with a positive family history of PD. One patient was found to be heterozygous for both a PARK2 mutation and a missense mutation (A6T) in TH of unknown significance. It cannot be excluded that both mutations contribute to the phenotype. No other putative disease causing TH or GCH1 mutations were found. In conclusion, homozygous, or compound heterozygous PARK2 mutations, and mutations in GCH1 and TH, are rare even in a population of PD patients with early-onset of the disease.
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GTP Ciclohidrolasa/genética , Enfermedad de Parkinson/genética , Tirosina 3-Monooxigenasa/genética , Ubiquitina-Proteína Ligasas/genética , Adulto , Edad de Inicio , Análisis Mutacional de ADN , Dinamarca , Femenino , Humanos , Masculino , Mutación , Reacción en Cadena de la Polimerasa , Polimorfismo Conformacional Retorcido-SimpleRESUMEN
AIM: The aim of the present investigation is to study the epidemiology of Alport syndrome in southern Sweden, to search for mutations in the COL4A5 gene and to estimate the mutation frequency. PATIENTS AND METHODS: Patients with suspected Alport syndrome were identified in an area with a population of 1.45 million. Clinical criteria were used to establish the diagnosis and samples for mutation analysis were collected. Mutation analyses were performed with Single-Stranded Conformation Polymorphism analysis (SSCP) of PCR-amplified genomic DNA. RESULTS: Altogether 25 families with hereditary nephritis were identified. Alport syndrome with X-linked transmission was evident in 14 families, with juvenile (< 31 years) progression to end-stage renal failure (ESRF) in ten, and adult (> or = 31 years) in four families. CONCLUSION: The frequency of males with X-linked disease was calculated to one in 17,000 male births (95% confidence interval (CI) 1/10,500-1/28,600), and the prevalence to one in 40,000. A total of seven females with ESRF were identified, with a median age at ESRF of 45 years. The male to female ratio of cases with ESRF was 4.9 to 1. The risk of developing ESRF among females was from the expected incidence roughly estimated to 12%. Patients with X-linked disease constituted 1.8% of patients with ESRF in the examined area. A mutation was identified positive in 10 of 14 families with X-linked disease, but never in families not fulfilling the clinical criteria for Alport syndrome. In families with juvenile phenotype and positive mutation analysis, the mutation frequency was calculated to between 1/78,000 and 1/198,000 (95% CI 1/42,000-1/177,000) if the effective fertility was estimated to be between 0 and 0.2.
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Nefritis Hereditaria/epidemiología , Adolescente , Adulto , Anciano , Cromosomas Humanos X , Análisis Mutacional de ADN , Femenino , Ligamiento Genético , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Nefritis Hereditaria/genética , Reacción en Cadena de la Polimerasa , Suecia/epidemiología , SíndromeAsunto(s)
Ataxia Cerebelosa/genética , Cromosomas Humanos Par 20/genética , Cromosomas Humanos Par 8/genética , Translocación Genética/genética , Adulto , Edad de Inicio , Ataxia Cerebelosa/fisiopatología , Niño , Preescolar , Rotura Cromosómica/genética , Progresión de la Enfermedad , Femenino , Humanos , Hibridación Fluorescente in Situ , Lactante , Cariotipificación , Masculino , Persona de Mediana Edad , Linaje , Mapeo Físico de CromosomaRESUMEN
We study a random heteropolymer model with Langevin dynamics, in the supersymmetric formulation. Employing a procedure similar to one that has been used in static calculations, we construct an ensemble in which the affinity of the system for a native state is controlled by a "selection temperature" T0. In the limit of high T0, the model reduces to a random heteropolymer, while for T0-->0 the system is forced into the native state. Within the Gaussian variational approach that we employed previously for the random heteropolymer, we explore the phases of the system for high and low T0. For high T0, the system exhibits a (dynamical) spin-glass phase, like that found for the random heteropolymer, below a temperature T(g). For low T0, we find an ordered phase, characterized by a nonzero overlap with the native state, below a temperature T(n) proportional to 1/T(0)>T(g). However, the random-globule phase remains locally stable below T(n), down to the dynamical glass transition at T(g). Thus, in this model, folding is rapid for temperatures between T(g) and T(n), but below T(g) the system can get trapped in conformations uncorrelated with the native state. At a lower temperature, the ordered phase can also undergo a dynamical glass transition, splitting into substates separated by large barriers.