RESUMO
Seven subunits of the mitochondrial contact site and cristae junction (CJ) organizing system (MICOS) in humans have been recently described in function and structure. QIL1 (also named MIC13) is a small complex that is crucial for the maintenance and assembling of MICOS. A novel mutation of an essential splice site in the C19orf70 gene encoding QIL1 induces severe mitochondrial encephalopathy, hepatopathy and lactate acidosis consistent with psychomotor retardation. In addition, bilateral kidney stones were observed. Disassembly of MICOS complex subunits displays lack of MIC10-MIC26-MIC27-QIL1 subcomplex, resulting in aberrant cristae structure and a loss of cristae junctions and contact sites. In liver and muscle tissue, the activity of the respiratory chain complexes (OXPHOS) was severely impaired. Defects in MICOS complex do not only affect mitochondrial architecture, but also mitochondrial fusion, metabolic signalling, lipid trafficking and cellular electric homeostasis.
Assuntos
Genes Letais , Hepatopatias/genética , Proteínas de Membrana/genética , Mitocôndrias/metabolismo , Encefalomiopatias Mitocondriais/genética , Proteínas Mitocondriais/genética , Mutação , Desempenho Psicomotor , Acidose Láctica/complicações , Encéfalo/diagnóstico por imagem , Transporte de Elétrons , Evolução Fatal , Feminino , Humanos , Lactente , Recém-Nascido , Cálculos Renais/complicações , Fígado/metabolismo , Hepatopatias/complicações , Hepatopatias/fisiopatologia , Imageamento por Ressonância Magnética , Encefalomiopatias Mitocondriais/complicações , Encefalomiopatias Mitocondriais/diagnóstico por imagem , Encefalomiopatias Mitocondriais/fisiopatologia , Músculos/metabolismo , Fases de Leitura Aberta , Fosforilação Oxidativa , Sítios de Splice de RNARESUMO
Congenital disorders of glycosylation (CDG) are a group of hereditary metabolic diseases characterized by abnormal glycosylation of proteins and lipids. Often, multisystem disorders with central nervous system involvement and a large variety of clinical symptoms occur. The main characteristics are developmental delay, seizures, and ataxia. In this paper we report the clinical and biochemical characteristics of a 5-year-old girl with a defective galactosylation of N-glycans, resulting in developmental delay, muscular hypotonia, epileptic seizures, inverted nipples, and visual impairment. Next generation sequencing revealed a de novo mutation (c.797G > T, p.G266V) in the X-chromosomal gene SLC35A2 (solute carrier family 35, UDP-galactose transporter, member A2; MIM 300896). While this mutation was found heterozygous, random X-inactivation of the normal allele will lead to loss of normal SLC35A2 activity in respective cells. The functional relevance of the mutation was demonstrated by complementation of UGT-deficient MDCK-RCA(r) and CHO-Lec8 cells by normal UGT-expression construct but not by the mutant version. The effect of dietary galactose supplementation on glycosylation was investigated, showing a nearly complete normalization of transferrin glycosylation.
Assuntos
Defeitos Congênitos da Glicosilação/genética , Defeitos Congênitos da Glicosilação/terapia , Proteínas de Transporte de Monossacarídeos/genética , Animais , Células CHO , Pré-Escolar , Cricetinae , Cricetulus , Análise Mutacional de DNA , Cães , Feminino , Galactose/uso terapêutico , Humanos , Células Madin Darby de Rim Canino , Proteínas de Transporte de Monossacarídeos/deficiência , FenótipoRESUMO
Congenital disorders of glycosylation form a rapidly growing group of inherited metabolic diseases. As glycosylation affects proteins all over the organism, a mutation in a single gene leads to a multisystemic disorder. We describe a patient with TMEM165-CDG with facial dysmorphism, nephrotic syndrome, cardiac defects, enlarged cerebral ventricles, feeding problems, and neurological involvement. Having confirmed the diagnosis via prenatal diagnostics, we were able to observe the glycosylation right from birth, finding a pathological pattern already on the first day of life. Within the next few weeks, hypoglycosylation progressed to less sialylated and then also to hypogalactosylated isoforms. On the whole, there has not been much published evidence concerning postnatal glycosylation and its adaptational process. This is the first paper reporting changes in glycosylation patterns over the first postnatal weeks in TMEM165-CDG.
Assuntos
Percepção Auditiva , Transtornos Cognitivos , Memória , Humanos , Aprendizagem Verbal , Percepção VisualRESUMO
If a viable kidney transplant programme is to be continued on a national basis, many of the problems at present surrounding organ transplantation must be tackled urgently. This paper discusses the psychological and emotional problems which are presently seen to hinder a successful renal transplantation policy, and considers the relative advantages and disadvantages of the kidney donor card scheme.
Assuntos
Transplante de Rim , Doadores de Tecidos/psicologia , Atitude do Pessoal de Saúde , Humanos , Jurisprudência , Legislação Médica , Diálise Renal/economia , Transplante Homólogo , Reino UnidoRESUMO
This paper discusses the evidence on the confidence-accuracy relationship in eyewitness research. It is pointed out that the conclusion often drawn on the basis of such research, that there is little or no relationship between eyewitness confidence and accuracy, is an unwarranted generalisation based on the use of experimental paradigms that are limited in terms of their generalisability to courtroom situations. In particular, almost all studies involve between-subject rather than within-subject designs, thereby limiting the generalisability of findings. A within-subjects analysis examines whether, within an individual, more confident responses are associated with greater accuracy than are less confident responses. A between-subjects analysis examines whether a more confident individual is likely to be more accurate than a less confident individual. A further limitation on the generalisability to real life situations of studies conducted to date is that experiments must involve making errors in identification in order to allow correlational analysis to take place. This means that findings cannot be generalised to those real life situations where all subjects are likely to be completely accurate and confident.
Assuntos
Jurisprudência , Memória , Projetos de Pesquisa , Humanos , Julgamento , Reprodutibilidade dos TestesRESUMO
The laboratory mouse C57BL genome contains about 50 copies of a long-range repeat DNA family clustered in the C-D region of chromosome 1. The repeat length is more than 50 kb and includes sequences homologous to at least two mRNAs. There are small differences in the copies of this repeat family such as restriction site mutations and gross differences like rearrangements and insertions of LINE1 elements. A germline homogeneously staining region occurring as a chromosome 1 polymorphism in many feral populations of the house mouse is an amplified version of this long-range repeat cluster.
Assuntos
Sequências Repetitivas de Ácido Nucleico , Animais , Southern Blotting , Clonagem Molecular , Sondas de DNA , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Eletroforese em Gel de Campo Pulsado , Amplificação de Genes , Genoma , Células Germinativas , Camundongos , Camundongos Endogâmicos C57BL , Muridae , Polimorfismo de Fragmento de Restrição , Mapeamento por Restrição , Homologia de Sequência do Ácido Nucleico , Coloração e RotulagemRESUMO
In an infant with typical pyridoxine-dependent seizures, CSF GABA level, was determined before treatment with pyridoxine. Before onset of treatment, level of GABA in CSF was highly lowered (16 pmol/ml), pyridoxine level in serum was within normal range. Immediately after application of 80 mg pyridoxine fits stopped and the EEG was without seizure activity. The data substantiate previous findings in brain tissue from a patient with pyridoxine-dependent seizures. They are proof of a disturbed GABA metabolism in pyridoxine dependent seizures.
Assuntos
Piridoxina/metabolismo , Convulsões/metabolismo , Ácido gama-Aminobutírico/metabolismo , Encéfalo/metabolismo , Cromossomos Humanos Par 2 , Glutamato Descarboxilase/biossíntese , Humanos , Lactente , Recém-Nascido , Injeções Intravenosas , Masculino , Ligação Proteica/genética , Piridoxina/efeitos adversos , Piridoxina/uso terapêutico , Convulsões/tratamento farmacológico , Ácido gama-Aminobutírico/biossíntese , Ácido gama-Aminobutírico/líquido cefalorraquidianoRESUMO
Reference values for tubular transport of sodium, phosphate, glucose and amino acids are generally based on inulin or creatinine short-term clearances, which are difficult to obtain in children. Hence, quantitative assessment of tubular transport capacities is rarely performed. For a simplified procedure, reference values for fractional sodium excretion, phosphate reabsorption related to glomerular filtration rate, percent glucose and percent amino acid reabsorption were established in 62 children from spot urine and simultaneously obtained blood samples. Sodium excretion, and glucose and amino acid reabsorption were significantly lower in infants than children, whereas phosphate reabsorption decreased during the first year of life. Results using the proposed protocol and those obtained from timed urine specimens correlated well; the phenomenon of renal adaptation during childhood could equally well be demonstrated. Renal tubular dysfunction can be diagnosed without timed urine specimens.
Assuntos
Aminoácidos/urina , Glicemia/metabolismo , Desenvolvimento Infantil/fisiologia , Túbulos Renais/fisiologia , Fosfatos/urina , Sódio/urina , Absorção/fisiologia , Adolescente , Criança , Pré-Escolar , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Lactente , Recém-Nascido , Testes de Função Renal , Masculino , Valores de Referência , Erros Inatos do Transporte Tubular Renal/diagnóstico , Erros Inatos do Transporte Tubular Renal/urinaRESUMO
BACKGROUND AND OBJECTIVE: Disease management programs (DMP) e. g. for diabetes mellitus, should be the clinical and economic basis for a structured treatment. This article shows results of specialized outpatient treatment using a risk factor depending patient classification. PATIENTS AND METHODS: Diabetes associated co-morbidities, micro- and macrovascular complications, the results and findings of blood pressure and metabolism of glucose and lipids, as well as all treatment-associated costs of 5245 type 2 diabetics were collected for a period of 12 months, accompanied by different measures of quality control. For documentation in the centres, all available original data were used as local data sources. RESULTS: The patient classification system, on which diabetic risk profiles are based, covered 74.3 % of all type 2 diabetic patients. Daily direct costs for all treatment measures ranged between EUR 4.79 (primary prevention) and EUR 8.96 for patients suffering from advanced diabetic foot syndrome. Most of the treatment costs arose from prescriptions of pharmaceuticals, other remedies and aids. Specific strategies of therapy were both related to the severity of co-morbidities and the time since manifestation of diabetes (r = 0.486; p < 0.01, two-sided). The share of patients receiving diet and exercise only decreased from 22.8 % (primary prevention) to below 10 % of patients suffering from microvascular complications. Simultaneously, the share of patients receiving insulin increased up to 81.8 % of patients suffering from advanced diabetic retinopathy. CONCLUSION: The risk profile specific variation in the results clearly shows the need of a risk factor depending classification system for type 2 diabetes, which could be useful to reform and focus the system of compensating payments between health insurance companies more and more on morbidity, or on risk profiles.