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1.
Mol Genet Genomic Med ; 11(5): e2139, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36695166

RESUMO

BACKGROUND: Cardiac-urogenital syndrome [MIM # 618280] is a newly described very rare syndrome associated with pathogenic variants in the myelin regulatory factor (MYRF) gene that leads to loss of protein function. MYRF is a transcription factor previously associated only with the control of myelin-related gene expression. However, it is also highly expressed in other tissues and associated with various organ anomalies. The clinical picture is primarily dominated by complex congenital cardiac developmental defects, pulmonary hypoplasia, congenital diaphragmatic hernia, and urogenital malformations. CASE PRESENTATION: We present case reports of two siblings of unrelated parents in whom whole-exome sequencing was indicated due to familial occurrence of extensive developmental defects. A new, previously undescribed splicing pathogenic variant c.1388+2T>G in the MYRF gene has been identified in both patients. Both parents are unaffected, tested negative, and have another healthy daughter. The identical de novo event in siblings suggests gonadal mosaicism, which can mimic recessive inheritance. CONCLUSIONS: To our knowledge, this is the first published case of familial cardiac-urogenital syndrome indicating gonadal mosaicism.


Assuntos
Mosaicismo , Irmãos , Feminino , Humanos , Sequenciamento do Exoma , Síndrome , Fatores de Transcrição/genética
2.
Acta Paediatr ; 110(11): 2994-2999, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34289149

RESUMO

AIM: Extremely low birthweight (ELBW) neonates require a high protein intake, but this can be challenging in the very rare cases when they also have phenylketonuria (PKU). This is due to a lack of suitable parenteral nutrition or enteral formula. Our aim was to analyse tolerance to phenylalanine in these infants. MATERIAL: There are approximately 110 000 children born in the Czech Republic each year. A neonatal screening programme from 2005 to 2020 found that 320 neonates had PKU, including 30 premature neonates with a birth weight of less than 2500 g. RESULTS: This study focused on three neonates who were born with ELBWs of 720, 740 and 950 g, respectively. Phenylalanine levels normalised in ELBW neonates with PKU within 1 week of the introduction of low-phenylalanine parenteral or enteral nutrition. The tolerance to phenylalanine was very high (70-110 mg/kg) in the first months of life, due to a rapid weight gain, but significantly decreased during infancy. CONCLUSION: Extremely low birthweight neonates with PKU need special dietary management. Regular assessments of phenylalanine are necessary during the first weeks of life to allow prompt dietary adjustments that reflect rapid weight gain and transitory high tolerance to phenylalanine.


Assuntos
Fenilcetonúrias , Peso ao Nascer , Humanos , Lactente , Recém-Nascido , Triagem Neonatal , Nutrição Parenteral , Fenilalanina , Fenilcetonúrias/diagnóstico
3.
Diagnostics (Basel) ; 11(6)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071626

RESUMO

BACKGROUND: Alagille syndrome (ALGS) is a highly variable multisystem disorder inherited in an autosomal dominant pattern with incomplete penetration. The disorder is caused by mutations in the JAG1 gene, only rarely in the NOTCH2 gene, which gives rise to malformations in multiple organs. Bile duct paucity is the main characteristic feature of the disease. METHODS: Molecular-genetic examination of genes JAG1 and NOTCH2 in four probands of Czech origin who complied with the diagnostic criteria of ALGS was performed using targeted next-generation sequencing of genes JAG1 and NOTCH2. Segregation of variants in a family was assessed by Sanger sequencing of parental DNA. RESULTS: Mutations in the JAG1 gene were confirmed in all four probands. We identified two novel mutations: c.3189dupG and c.1913delG. Only in one case, the identified JAG1 mutation was de novo. None of the parents carrying JAG1 pathogenic mutation was diagnosed with ALGS. CONCLUSION: Diagnosis of the ALGS is complicated due to the absence of clear genotype-phenotype correlations and the extreme phenotypic variability in the patients even within the same family. This fact is of particular importance in connection to genetic counselling and prenatal genetic testing.

5.
Front Genet ; 11: 561054, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33133147

RESUMO

Congenital disorders of glycosylation (CDG) are a rapidly growing family of genetic diseases with the phosphomannomutase 2 (PMM2)-CDG being the most common form of CDG. Most of these monogenic diseases are autosomal recessive and have multi-systemic manifestations, mainly psychomotor retardation, facial dysmorphisms, characteristic distribution of the fat pads, and variable coagulation abnormalities. The association of fetal hydrops with CDG has been reported, and pericardial effusion was also rarely observed in patients with PMM2-CDG. Here we describe an infant boy with PMM2-CDG. The diagnosis was suspected based on inverted nipples, fat pads, and combined coagulopathy. However, the primary symptom was progressive pericardial effusion leading to patient death at the age of 3 months. Screening for CDG performed by the use of isoelectric focusing of serum transferrin showed a typical PMM2-CDG pattern. Exome sequencing revealed one common pathogenic variant (c.691G > A/p.Val231Met) and one novel variant (c.447 + 3dupA) in the PMM2 gene. Both PMM2 variants were further confirmed by Sanger sequencing in both the proband and the parents' DNA. The novel variant was predicted to result in loss of donor splice site, and the analysis at mRNA level confirmed that it leads to exon five skipping (r.348_447del) and causes premature termination of translation to the protein (p.G117Kfs∗4), therefore is classified as likely pathogenic. Although there is no curative therapy for the PMM2-CDG at the moment, the other supportive care options are available to be offered. The definite diagnosis of PMM2-CDG can also assist in the process of genetic counseling, family planning, and preimplantation genetic diagnosis.

6.
Genes (Basel) ; 10(6)2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208052

RESUMO

The molecular genetics of well-characterized inherited diseases, such as phenylketonuria (PKU) and hyperphenylalaninemia (HPA) predominantly caused by mutations in the phenylalanine hydroxylase (PAH) gene, is often complicated by the identification of many novel variants, often with no obvious impact on the associated disorder. To date, more than 1100 PAH variants have been identified of which a substantial portion have unknown clinical significance. In this work, we study the functionality of seven yet uncharacterized PAH missense variants p.Asn167Tyr, p.Thr200Asn, p.Asp229Gly, p.Gly239Ala, p.Phe263Ser, p.Ala342Pro, and p.Ile406Met first identified in the Czech PKU/HPA patients. From all tested variants, three of them, namely p.Asn167Tyr, p.Thr200Asn, and p.Ile406Met, exerted residual enzymatic activity in vitro similar to wild type (WT) PAH, however, when expressed in HepG2 cells, their protein level reached a maximum of 72.1% ± 4.9%, 11.2% ± 4.2%, and 36.6% ± 7.3% compared to WT PAH, respectively. Remaining variants were null with no enzyme activity and decreased protein levels in HepG2 cells. The chaperone-like effect of applied BH4 precursor increased protein level significantly for p.Asn167Tyr, p.Asp229Gly, p.Ala342Pro, and p.Ile406Met. Taken together, our results of functional characterization in combination with in silico prediction suggest that while p.Asn167Tyr, p.Thr200Asn, and p.Ile406Met PAH variants have a mild impact on the protein, p.Asp229Gly, p.Gly239Ala, p.Phe263Ser, and p.Ala342Pro severely affect protein structure and function.


Assuntos
Biopterinas/análogos & derivados , Mutação de Sentido Incorreto/genética , Fenilalanina Hidroxilase/química , Fenilcetonúrias/genética , Biopterinas/química , Biopterinas/genética , Simulação por Computador , Genótipo , Células Hep G2 , Humanos , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/metabolismo , Fenilcetonúrias/patologia , Relação Estrutura-Atividade
7.
PLoS One ; 12(4): e0176121, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28419152

RESUMO

A comparative analysis of various parameters that characterize plant morphology, growth, water status, photosynthesis, cell damage, and antioxidative and osmoprotective systems together with an iTRAQ analysis of the leaf proteome was performed in two inbred lines of maize (Zea mays L.) differing in drought susceptibility and their reciprocal F1 hybrids. The aim of this study was to dissect the parent-hybrid relationships to better understand the mechanisms of the heterotic effect and its potential association with the stress response. The results clearly showed that the four examined genotypes have completely different strategies for coping with limited water availability and that the inherent properties of the F1 hybrids, i.e. positive heterosis in morphological parameters (or, more generally, a larger plant body) becomes a distinct disadvantage when the water supply is limited. However, although a greater loss of photosynthetic efficiency was an inherent disadvantage, the precise causes and consequences of the original predisposition towards faster growth and biomass accumulation differed even between reciprocal hybrids. Both maternal and paternal parents could be imitated by their progeny in some aspects of the drought response (e.g., the absence of general protein down-regulation, changes in the levels of some carbon fixation or other photosynthetic proteins). Nevertheless, other features (e.g., dehydrin or light-harvesting protein contents, reduced chloroplast proteosynthesis) were quite unique to a particular hybrid. Our study also confirmed that the strategy for leaving stomata open even when the water supply is limited (coupled to a smaller body size and some other physiological properties), observed in one of our inbred lines, is associated with drought-resistance not only during mild drought (as we showed previously) but also during more severe drought conditions.


Assuntos
Vigor Híbrido , Proteínas de Plantas/metabolismo , Zea mays/genética , Zea mays/fisiologia , Aclimatação , Quimera/genética , Quimera/fisiologia , Secas , Fotossíntese , Folhas de Planta/anatomia & histologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/análise , Proteoma/análise , Proteoma/metabolismo , Estresse Fisiológico , Água/metabolismo , Zea mays/anatomia & histologia
8.
J Clin Res Pediatr Endocrinol ; 8(4): 482-483, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27217304

RESUMO

Wolfram-like syndrome (WFSL) is a rare autosomal dominant disease characterised by congenital progressive hearing loss, diabetes mellitus, and optic atrophy. The patient was a boy with the juvenile form of diabetes mellitus and findings which clinically matched the symptoms of Wolfram syndrome. At the age of 3 1/4 years, diabetes mellitus was diagnosed in this boy who also had severe psychomotor retardation, failure to thrive, a dysmorphic face with Peters anomaly type 3 (i.e. posterior central defect with stromal opacity of the cornea, adhering stripes of the iris, and cataract with corneolenticular adhesion), congenital glaucoma, megalocornea, severe hearing impairment, a one-sided deformity of the auricle with atresia of the bony and soft external auditory canal, non-differentiable eardrum, missing os incus, hypothyreosis, and nephrocalcinosis. Molecular-genetic examinations revealed a de novo mutation p.(Glu809Lys) in the WFS1 gene. No mutations were detected in the biological parents. The mutation p.(Glu809Lys) in the WFS1 gene is associated with WFSL.


Assuntos
Predisposição Genética para Doença/genética , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Síndrome de Wolfram/genética , Pré-Escolar , Análise Mutacional de DNA , Humanos , Masculino , Síndrome de Wolfram/diagnóstico
9.
J Pediatr Endocrinol Metab ; 28(11-12): 1327-32, 2015 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-26226119

RESUMO

PURPOSE: The objective of the study was to determine the incidence of vitamin B12 deficiency in patients under long-term treatment for phenylketonuria (PKU) and hyperphenylalaninemia (HPA), as well as its associations with B12 vitamin parameters (holotranscobalamin - active vitamin B12, serum folate, total plasma homocysteine, and plasma methylmalonic acid concentration). PATIENTS AND METHODS: The group consisted of 51 PKU (n=29) and HPA (n=22) patients aged 3-48 years (28 children, 23 adults). RESULTS: A significant difference in serum folate levels was discovered between adult HPA patients and PKU patients (p=0.004, Mann-Whitney U-test). A significant difference in plasma homocysteine concentrations within the normal levels (p=0.032, χ2-test) was detected between adult HPA and PKU patients. In the group of adults, we also found significant differences in serum holotranscobalamin concentrations regarding both concentration levels and the proportion of patients with concentrations within the normal levels (p=0.031, Mann-Whitney U-test; p=0.006, χ2-test). CONCLUSION: We have proven that adult patients with PKU and HPA are at risk of vitamin B12 nutritional deficiency. The most effective parameter for these adults is the monitoring of holotranscobalamin in the serum.


Assuntos
Fenilcetonúrias/complicações , Deficiência de Vitamina B 12/etiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Ácido Fólico/sangue , Homocisteína/sangue , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fenilcetonúrias/sangue , Fenilcetonúrias/tratamento farmacológico , Estudos Prospectivos , Risco , Medição de Risco , Transcobalaminas , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/epidemiologia , Adulto Jovem
10.
BMC Plant Biol ; 15: 85, 2015 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-25888402

RESUMO

BACKGROUND: Cytokinins (CKs) are involved in response to various environmental cues, including salinity. It has been previously reported that enhancing CK contents improved salt stress tolerance in tomato. However, the underlying mechanisms of CK metabolism and signaling under salt stress conditions remain to be deciphered. RESULTS: Two tomato isopentenyltransferases, SlIPT3 and SlIPT4, were characterized in tomato and Arabidopsis. Both proteins displayed isopentenyltransferase (IPT) activity in vitro, while their encoding genes exhibited different spatio-temporal expression patterns during tomato plant development. SlIPT3 and SlIPT4 were affected by the endogenous CK status, tightly connected with CKs feedback regulation, as revealed by hormonal treatements. In response to salt stress, SlIPT3 and SlIPT4 were strongly repressed in tomato roots, and differently affected in young and old leaves. SlIPT3 overexpression in tomato resulted in high accumulation of different CK metabolites, following modifications of CK biosynthesis-, signaling- and degradation-gene expression. In addition, 35S::SlIPT3 tomato plants displayed improved tolerance to salinity consecutive to photosynthetic pigments and K(+)/Na(+) ratio retention. Involvement of SlIPT3 and SlIPT4 in salt stress response was also observed in Arabidopsis ipt3 knock-out complemented plants, through maintenance of CK homeostasis. CONCLUSIONS: SlIPT3 and SlIPT4 are functional IPTs encoded by differently expressed genes, distinctively taking part in the salinity response. The substantial participation of SlIPT3 in CK metabolism during salt stress has been determined in 35S::SlIPT3 tomato transformants, where enhancement of CKs accumulation significantly improved plant tolerance to salinity, underlining the importance of this phytohormone in stress response.


Assuntos
Alquil e Aril Transferases/fisiologia , Arabidopsis/fisiologia , Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas , Tolerância ao Sal , Solanum lycopersicum/enzimologia , Solanum lycopersicum/fisiologia , Alquil e Aril Transferases/genética , Arabidopsis/genética , Solanum lycopersicum/embriologia , Solanum lycopersicum/genética , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/fisiologia
11.
J Plant Physiol ; 171(7): 559-64, 2014 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-24655392

RESUMO

Increased endogenous plant cytokinin (CK) content through transformation with an isopentyl transferase (ipt) gene has been associated with improved plant stress tolerance. The impact of zinc (tested levels Zn1=250, Zn2=500, Zn3=750mgkg(-1)soil) on gas exchange parameters (net photosynthetic rate, transpiration rate, stomatal conductance, intercellular CO2 concentration) and nitrogen utilization by plants resulted in changes of free amino acid concentrations (glutamic acid, glutamine, asparagine, aspartate, glycine, serine, cystein) and differed for transformed and non-transformed tobacco plants. For pot experiments, tobacco plants (Nicotiana tabacum L., cv. Wisconsin 38) transformed with a construct consisting of SAG12 promoter fused with the ipt gene for cytokinin synthesis (SAG plants) and its wild type (WT plants as a control) were used. Physiological analyses confirmed that SAG plants had improved zinc tolerance compared with the WT plants. The enhanced Zn tolerance of SAG plants was associated with the maintenance of accumulation of amino acids and with lower declines of photosynthetic and transpiration rates. In comparison to WT plants, SAG plants exposed to the highest Zn concentration accumulated lower concentrations of asparagine, which is a major metabolic product during senescence.


Assuntos
Citocininas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Nicotiana/efeitos dos fármacos , Nicotiana/genética , Proteínas de Plantas/genética , Zinco/toxicidade , Aminoácidos/metabolismo , Nitrogênio/metabolismo , Fotossíntese/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas , Nicotiana/metabolismo
12.
Brain ; 137(Pt 4): 1030-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24566669

RESUMO

Congenital disorders of glycosylation comprise a group of genetic defects with a high frequency of intellectual disability, caused by deficient glycosylation of proteins and lipids. The molecular basis of the majority of the congenital disorders of glycosylation type I subtypes, localized in the cytosol and endoplasmic reticulum, has been solved. However, elucidation of causative genes for defective Golgi glycosylation (congenital disorders of glycosylation type II) remains challenging because of a lack of sufficiently specific diagnostic serum methods. In a single patient with intellectual disability, whole-exome sequencing revealed MAN1B1 as congenital disorder of glycosylation type II candidate gene. A novel mass spectrometry method was applied for high-resolution glycoprofiling of intact plasma transferrin. A highly characteristic glycosylation signature was observed with hybrid type N-glycans, in agreement with deficient mannosidase activity. The speed and robustness of the method allowed subsequent screening in a cohort of 100 patients with congenital disorder of glycosylation type II, which revealed the characteristic glycosylation profile of MAN1B1-congenital disorder of glycosylation in 11 additional patients. Abnormal hybrid type N-glycans were also observed in the glycoprofiles of total serum proteins, of enriched immunoglobulins and of alpha1-antitrypsin in variable amounts. Sanger sequencing revealed MAN1B1 mutations in all patients, including severe truncating mutations and amino acid substitutions in the alpha-mannosidase catalytic site. Clinically, this group of patients was characterized by intellectual disability and delayed motor and speech development. In addition, variable dysmorphic features were noted, with truncal obesity and macrocephaly in ∼65% of patients. In summary, MAN1B1 deficiency appeared to be a frequent cause in our cohort of patients with unsolved congenital disorder of glycosylation type II. Our method for analysis of intact transferrin provides a rapid test to detect MAN1B1-deficient patients within congenital disorder of glycosylation type II cohorts and can be used as efficient diagnostic method to identify MAN1B1-deficient patients in intellectual disability cohorts. In addition, it provides a functional confirmation of MAN1B1 mutations as identified by next-generation sequencing in individuals with intellectual disability.


Assuntos
Deficiência Intelectual/diagnóstico , Deficiência Intelectual/genética , Proteínas de Membrana/deficiência , Proteínas de Membrana/genética , Proteínas Nucleares/deficiência , Proteínas Nucleares/genética , Adolescente , Adulto , Pré-Escolar , Análise Mutacional de DNA/métodos , Proteínas de Ligação a DNA , Feminino , Glicosilação , Humanos , Lactente , Deficiência Intelectual/sangue , Masculino , Proteínas de Membrana/sangue , Mutação , Proteínas Nucleares/sangue , Adulto Jovem
13.
Ecotoxicol Environ Saf ; 100: 166-70, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24238718

RESUMO

Increased endogenous plant cytokinin (CK) content through transformation with an isopentyl transferase (ipt) gene has been associated with improved plant stress tolerance. The objective of this study is to determine amino acid changes associated with elevated CK production in ipt transgenic tobacco (Nicotiana tabacum L., cv. Wisconsin 38). Nontransformed (WT) and transformed tobacco plants with ipt gene controlled by senescence-activated promoter (SAG) were exposed to zinc soil contamination (tested levels Zn1=250, Zn2=500, Zn3=750 mg kg(-1) soil). The Zn effect on plant stress metabolism resulted in changes in levels of selected free amino acids playing an important role in adaptation to stress and plant senescence (alanine, leucine, proline, methionine and γ-aminobutyrate) and differed for transformed and nontransformed tobacco plants. Analyses of amino acids confirmed that SAG tobacco plants had improved zinc tolerance compared with the WT plants. The enhanced Zn tolerance of SAG plants was associated with the maintenance of accumulation of proline, methionine and γ-aminobutyrate. The concentrations of leucine and alanine did not show significant differences between plant lines.


Assuntos
Aminoácidos/metabolismo , Nicotiana/fisiologia , Poluentes do Solo/toxicidade , Zinco/toxicidade , Adaptação Fisiológica/efeitos dos fármacos , Aminoácidos/análise , Citocininas/genética , Citocininas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Regiões Promotoras Genéticas , Tempo , Nicotiana/genética , Nicotiana/metabolismo
14.
Biol Trace Elem Res ; 154(2): 178-84, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23771645

RESUMO

Phenylketonuria is an inherited disorder of metabolism of the amino acid phenylalanine caused by a deficit of the enzyme phenylalanine hydroxylase. It is treated with a low-protein diet containing a low content of phenylalanine to prevent mental affection of the patient. Because of the restricted intake of high-biologic-value protein, patients with phenylketonuria may have lower than normal serum concentrations of pre-albumin, selenium, zinc and iron. The objective of the present study was to assess the compliance of our phenylketonuric (PKU) and hyperphenylalaninemic (HPA) patients; to determine the concentration of serum pre-albumin, selenium, zinc and iron to discover the potential correlation between the amount of proteins in food and their metabolic control. We studied 174 patients of which 113 were children (age 1-18), 60 with PKU and 53 with HPA and 61 were adults (age 18-42), 51 with PKU and 10 with HPA. We did not prove a statistically significant difference in the concentration of serum pre-albumin, zinc and iron among the respective groups. We proved statistically significant difference in serum selenium concentrations of adult PKU and HPA patients (p = 0.006; Mann-Whitney U test). These results suggest that controlled low-protein diet in phenylketonuria and hyperphenylalaninemia may cause serum selenium deficiency in adult patients.


Assuntos
Dieta com Restrição de Proteínas/efeitos adversos , Fenilcetonúrias , Selênio , Adolescente , Adulto , Criança , Pré-Escolar , República Tcheca , Feminino , Humanos , Lactente , Masculino , Fenilcetonúrias/sangue , Fenilcetonúrias/dietoterapia , Estudos Prospectivos , Selênio/sangue , Selênio/deficiência
15.
Clin Chim Acta ; 419: 1-10, 2013 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-23357515

RESUMO

BACKGROUND: Hyperphenylalaninemia (HPA) is one of the most common inherited metabolic disorders caused by deficiency of the enzyme phenylalanine hydroxylase (PAH). HPA is associated with mutations in the PAH gene, which leads to reduced protein stability and/or impaired catalytic function. Currently, almost 700 different disease-causing mutations have been described. The impact of mutations on enzyme activity varies ranging from classical PKU, mild PKU, to non-PKU HPA phenotype. METHODS: We provide results of molecular genetic diagnostics of 665 Czech unrelated HPA patients, structural analysis of missense mutations associated with classical PKU and non-PKU HPA phenotype, and prediction of effects of 6 newly discovered HPA missense mutations using bioinformatic approaches and Molecular Dynamics simulations. RESULTS: Ninety-eight different types of mutations were indentified. Thirteen of these were novel (6 missense, 2 nonsense, 1 splicing, and 4 small gene rearrangements). Structural analysis revealed that classical PKU mutations are more non-conservative compared to non-PKU HPA mutations and that specific sequence and structural characteristics of a mutation might be critical when distinguishing between non-PKU HPA and classical PKU mutations. The greatest impact was predicted for the p.(Phe263Ser) mutation while other novel mutations p.(Asn167Tyr), p.(Thr200Asn), p.(Asp229Gly), p.(Leu358Phe), and p.(Ile406Met) were found to be less deleterious.


Assuntos
Estudos de Associação Genética , Mutação de Sentido Incorreto/genética , Fenilcetonúrias/genética , Biologia Computacional , Simulação por Computador , República Tcheca , Genótipo , Humanos , Simulação de Dinâmica Molecular , Fenótipo , Fenilcetonúrias/diagnóstico
16.
PLoS One ; 7(6): e38017, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22719860

RESUMO

Understanding the response of a crop to drought is the first step in the breeding of tolerant genotypes. In our study, two maize (Zea mays L.) genotypes with contrasting sensitivity to dehydration were subjected to moderate drought conditions. The subsequent analysis of their physiological parameters revealed a decreased stomatal conductance accompanied by a slighter decrease in the relative water content in the sensitive genotype. In contrast, the tolerant genotype maintained open stomata and active photosynthesis, even under dehydration conditions. Drought-induced changes in the leaf proteome were analyzed by two independent approaches, 2D gel electrophoresis and iTRAQ analysis, which provided compatible but only partially overlapping results. Drought caused the up-regulation of protective and stress-related proteins (mainly chaperones and dehydrins) in both genotypes. The differences in the levels of various detoxification proteins corresponded well with the observed changes in the activities of antioxidant enzymes. The number and levels of up-regulated protective proteins were generally lower in the sensitive genotype, implying a reduced level of proteosynthesis, which was also indicated by specific changes in the components of the translation machinery. Based on these results, we propose that the hypersensitive early stomatal closure in the sensitive genotype leads to the inhibition of photosynthesis and, subsequently, to a less efficient synthesis of the protective/detoxification proteins that are associated with drought tolerance.


Assuntos
Adaptação Fisiológica , Desidratação , Secas , Estômatos de Plantas/fisiologia , Proteômica , Zea mays/fisiologia , Antioxidantes/metabolismo , Catalase/metabolismo , Eletroforese em Gel Bidimensional , Genótipo , Glutationa Redutase/metabolismo , Superóxido Dismutase/metabolismo , Zea mays/enzimologia , Zea mays/genética
17.
J Chromatogr A ; 1226: 11-7, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22018716

RESUMO

Metabolomics has become an important tool in clinical research and diagnosis of human diseases. In this work we focused on the diagnosis of inherited metabolic disorders (IMDs) in plasma samples using a targeted metabolomic approach. The plasma samples were analyzed with the flow injection analysis method. All the experiments were performed on a QTRAP 5500 tandem mass spectrometer (AB SCIEX, U.S.A.) with electrospray ionization. The compounds were measured in a multiple reaction monitoring mode. We analyzed 50 control samples and 34 samples with defects in amino acid metabolism (phenylketonuria, maple syrup urine disease, tyrosinemia I, argininemia, homocystinuria, carbamoyl phosphate synthetase deficiency, ornithine transcarbamylase deficiency, nonketotic hyperglycinemia), organic acidurias (methylmalonic aciduria, propionic aciduria, glutaric aciduria I, 3-hydroxy-3-methylglutaric aciduria, isovaleric aciduria), and mitochondrial defects (medium-chain acyl-coenzyme A dehydrogenase deficiency, carnitine palmitoyltransferase II deficiency). The controls were distinguished from the patient samples by principal component analysis and hierarchical clustering. Approximately 80% of patients were clearly detected by absolute metabolite concentrations, the sum of variance for first two principle components was in the range of 44-55%. Other patient samples were assigned due to the characteristic ratio of metabolites (the sum of variance for first two principle components 77 and 83%). This study has revealed that targeted metabolomic tools with automated and unsupervised processing can be applied for the diagnosis of various IMDs.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos/sangue , Metabolômica/métodos , Adolescente , Adulto , Erros Inatos do Metabolismo dos Aminoácidos/diagnóstico , Criança , Pré-Escolar , Análise por Conglomerados , Feminino , Análise de Injeção de Fluxo , Humanos , Masculino , Metaboloma , Análise de Componente Principal , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
18.
Nitric Oxide ; 24(2): 61-5, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21256240

RESUMO

Leaf senescence is often associated with increased oxidative damage to cellular macromolecules by reactive oxygen species. However, very little is known about other radicals: gaseous free radical nitric oxide and related molecules--reactive nitrogen species. This review brings a short survey of the questions.


Assuntos
Óxido Nítrico/química , Plantas/química , Plantas/enzimologia , Espécies Reativas de Nitrogênio/química , Dioxigenases/metabolismo , Óxido Nítrico/toxicidade , Desenvolvimento Vegetal , Plantas/toxicidade
19.
Cas Lek Cesk ; 149(9): 411-6, 2010.
Artigo em Tcheco | MEDLINE | ID: mdl-21117323

RESUMO

BACKGROUND: Hereditary tyrosinemia type 1 (HT1) is a rare autosomal recessive inborn error of metabolism caused by deficiency of fumarylacetoacetate hydrolase. HT1 manifests with severe liver and kidney impairment and associates with an increased risk of liver cancer development. The aim of our study is to present a detailed clinical picture and results of biochemical and molecular genetic analyses in 11 Czech patients with HT1 diagnosed in our clinic within 1982-2006. METHODS AND RESULTS: In 9 patients the disease manifested between 1.5-7 months of age with refusal to eat, failure to thrive and vomiting. In 4 children HT1 progressed to acute liver failure. One clinically healthy boy was diagnosed because of affected sister. In one boy with liver cirrhosis the diagnosis was delayed until the age of 5.5 years. In all children the biochemical investigation showed elevated liver enzymes, alpha1-fetoprotein and hypophosphatemic rickets. Metabolic investigation revealed increased plasma tyrosine level, urinary excretion of succinylacetone and in 8 measured patients also increased urinary delta-aminolevulinic acid concentration. Three patients born before 1988 died due to liver cancer development (two of them) or liver failure. The average age of our 8 living patients is 10.7 +/- 8.3 years. Mutation analysis of FAH gene confirmed the HT1 in these patients and three novel mutations were found in FAH gene: c.579C>A, c.680G>T and c.1210G>A. Clinical status in six patients is favourable on strict low protein diet combined with Orfadin therapy. However, in two children despite of the maximal available therapy lasting 2 and 10 years resp., the disease progressed towards liver cancer development and necessity of liver transplantation. CONCLUSIONS: Early diagnostics of HT1 as a part of extended newborn screening is the only possibility to further improve the prognosis of the patients. Moreover, available molecular-genetic analysis of the FAH gene enables prenatal diagnostics in affected families.


Assuntos
Tirosinemias/diagnóstico , Criança , Pré-Escolar , Feminino , Humanos , Hidrolases/genética , Lactente , Masculino , Mutação , Tirosinemias/genética , Tirosinemias/metabolismo , Tirosinemias/terapia
20.
Biol Trace Elem Res ; 133(3): 265-9, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19562272

RESUMO

The purpose of this study was to determine the different levels of copper and zinc in the serum, urine, and scalp hair of patients with Wilson's disease receiving different, currently accepted methods of treatment to reduce the copper load (penicillamine-group 1, n = 8; zinc-group 2, n = 8; penicillamine+zinc-group 3, n = 8). Blood, urine, and hair samples were collected from the patients. All three treatments resulted in a significant decrease of the serum copper levels. Significantly increased levels of zinc in the serum were detected in the patients in groups 2 and 3 (19.1 and 18.8 micromol/l, respectively; p < 0.05). Copper excretion in the urine significantly increased during its administration to groups 1 and 3 (11.5 and 7.94 micromol/24 h respectively; p < 0.001) due to the effect of penicillamine. The administration of zinc as monotherapy (group 2) or in combination with penicillamine (group 3) led to an increase of its excretion (25.3 and 22.4 micromol/24 h, respectively; p < 0.01). Only an insignificant rise of the copper content in the hair was found in all three groups of patients. The content of zinc in the hair did not differ significantly in any of the groups in comparison with the control group.


Assuntos
Cobre/análise , Cobre/sangue , Cobre/urina , Degeneração Hepatolenticular/sangue , Degeneração Hepatolenticular/tratamento farmacológico , Degeneração Hepatolenticular/urina , Penicilamina/uso terapêutico , Zinco/análise , Zinco/sangue , Zinco/urina , Adolescente , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Cabelo/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Zinco/uso terapêutico
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