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1.
Cancers (Basel) ; 15(6)2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36980757

RESUMO

Fanconi anemia (FA) patients display an exacerbated risk of oral squamous cell carcinoma (OSCC) and oral potentially malignant lesions (OPMLs) at early ages. As patients have defects in their DNA repair mechanisms, standard-of-care treatments for OSCC such as radiotherapy and chemotherapy, give rise to severe toxicities. New methods for early diagnosis are urgently needed to allow for treatment in early disease stages and achieve better clinical outcomes. We conducted a prospective, longitudinal study wherein liquid biopsies from sixteen patients with no clinical diagnoses of OPML and/or OSCC were analyzed for the presence of mutations in cancer genes. The DNA from saliva and plasma were sequentially collected and deep-sequenced, and the clinical evaluation followed over a median time of approximately 2 years. In 9/16 FA patients, we detected mutations in cancer genes (mainly TP53) with minor allele frequencies (MAF) of down to 0.07%. Importantly, all patients that had mutations and clinical follow-up data after mutation detection (n = 6) developed oral precursor lesions or OSCC. The lead-time between mutation detection and tumor diagnosis ranged from 23 to 630 days. Strikingly, FA patients without mutations displayed a significantly lower risk of developing precursor lesions or OSCCs. Therefore, our diagnostic approach could help to stratify FA patients into risk groups, which would allow for closer surveillance for OSCCs or precursor lesions.

3.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artigo em Inglês | MEDLINE | ID: mdl-35042802

RESUMO

A global international initiative, such as the Earth BioGenome Project (EBP), requires both agreement and coordination on standards to ensure that the collective effort generates rapid progress toward its goals. To this end, the EBP initiated five technical standards committees comprising volunteer members from the global genomics scientific community: Sample Collection and Processing, Sequencing and Assembly, Annotation, Analysis, and IT and Informatics. The current versions of the resulting standards documents are available on the EBP website, with the recognition that opportunities, technologies, and challenges may improve or change in the future, requiring flexibility for the EBP to meet its goals. Here, we describe some highlights from the proposed standards, and areas where additional challenges will need to be met.


Assuntos
Sequência de Bases/genética , Eucariotos/genética , Genômica/normas , Animais , Biodiversidade , Genômica/métodos , Humanos , Padrões de Referência , Valores de Referência , Análise de Sequência de DNA/métodos , Análise de Sequência de DNA/normas
4.
Materials (Basel) ; 14(17)2021 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-34501021

RESUMO

This work applies a procedure for analysis and characterization of the surface of brake friction materials, correlating them with the tribological and thermal properties achieved in different vehicle braking conditions. Experiments were performed in a vehicle under two real conditions of braking operation, simulated flat track descent and emergency braking. Characteristics of the plates formed on the surfaces of the friction materials were analyzed by scanning electron microscopy (SEM) and correlated with the performance during braking, as measured by the coefficient of friction at the interface of the friction pair and temperature. As a result, the formation of the primary and secondary plateaus in these two different braking operating conditions was observed, and the relationship between the characteristics of the plateaus formed on the surface and the surface roughness parameters and performance measurements during braking.

5.
Int J Biol Macromol ; 126: 359-366, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30572056

RESUMO

The combination of bismuth(III) citrate and the antibiotic furazolidone (FDZ) results in a synergetic effect on Helicobacter pylori eradication. However, the problems associated with their oral administration are challenges to overcome. Thus, in the present study, sodium alginate (SA)/carboxymethyl cellulose (CMC) blend hydrogels (SC) were developed for concomitant and controlled release of furazolidone and bismuth(III). The blank formulation (SCblank) and the three drug-loaded hydrogels (SCFDZ, SCBi, and SCFDZ-Bi) were prepared by casting method and characterized by infrared spectroscopy, scanning electron microscopy, differential scanning calorimetry, and X ray powder diffraction analyses. The swelling equilibrium and cumulative release amounts of FDZ and Bi3+ have indicated distinct behaviors of the hydrogels to different pH values. The bismuth-containing sample (SCFDZ-Bi) presents more resistance to degradation on a neutral solution and shows more suitable properties for controlled drug release than the sample without bismuth (SCFDZ). Microbiological studies, using Escherichia coli as a model, show bacteria viability reduction in presence of the drug-loaded samples. The developed system containing furazolidone and bismuth(III) appears to be promising for oral administration with concomitant and controlled release of these drugs aimed at the pharmacological treatment of gastrointestinal disorders.


Assuntos
Alginatos/química , Bismuto/farmacologia , Carboximetilcelulose Sódica/química , Reagentes de Ligações Cruzadas/química , Furazolidona/farmacologia , Antibacterianos/farmacologia , Varredura Diferencial de Calorimetria , Preparações de Ação Retardada/farmacologia , Liberação Controlada de Fármacos , Escherichia coli/efeitos dos fármacos , Hidrogéis/química , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X
6.
Proc Natl Acad Sci U S A ; 115(17): 4325-4333, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29686065

RESUMO

Increasing our understanding of Earth's biodiversity and responsibly stewarding its resources are among the most crucial scientific and social challenges of the new millennium. These challenges require fundamental new knowledge of the organization, evolution, functions, and interactions among millions of the planet's organisms. Herein, we present a perspective on the Earth BioGenome Project (EBP), a moonshot for biology that aims to sequence, catalog, and characterize the genomes of all of Earth's eukaryotic biodiversity over a period of 10 years. The outcomes of the EBP will inform a broad range of major issues facing humanity, such as the impact of climate change on biodiversity, the conservation of endangered species and ecosystems, and the preservation and enhancement of ecosystem services. We describe hurdles that the project faces, including data-sharing policies that ensure a permanent, freely available resource for future scientific discovery while respecting access and benefit sharing guidelines of the Nagoya Protocol. We also describe scientific and organizational challenges in executing such an ambitious project, and the structure proposed to achieve the project's goals. The far-reaching potential benefits of creating an open digital repository of genomic information for life on Earth can be realized only by a coordinated international effort.


Assuntos
Biodiversidade , Espécies em Perigo de Extinção , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Planeta Terra
7.
Polymers (Basel) ; 10(2)2018 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30966179

RESUMO

In the vacuum thermoforming process, the group effects of the processing parameters, when related to the minimizing of the product deviations set, have conflicting and non-linear values which make their mathematical modelling complex and multi-objective. Therefore, this work developed models of prediction and optimization using artificial neural networks (ANN), having the processing parameters set as the networks' inputs and the deviations group as the outputs and, furthermore, an objective function of deviation minimization. For the ANN data, samples were produced in experimental tests of a product standard in polystyrene, through a fractional factorial design (2k-p). Preliminary computational studies were carried out with various ANN structures and configurations with the test data until reaching satisfactory models and, afterwards, multi-criteria optimization models were developed. The validation tests were developed with the models' predictions and solutions showed that the estimates for them have prediction errors within the limit of values found in the samples produced. Thus, it was demonstrated that, within certain limits, the ANN models are valid to model the vacuum thermoforming process using multiple parameters for the input and objective, by means of reduced data quantity.

8.
Muscle Nerve ; 55(6): 916-918, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-27859426

RESUMO

INTRODUCTION: McArdle disease is a metabolic myopathy that presents with exercise intolerance and episodic rhabdomyolysis. Excessive muscle recruitment has also been shown to be present during strenuous exercise, suggesting decreased power output. These findings could potentially be explained by either impaired contractility, decreased fiber size, or altered fiber type proportion. However, there is a paucity of data on the morphological features seen on muscle histology. METHODS: We examined muscle biopsies of patients with McArdle disease from a Spanish cohort and compared the findings with healthy controls. RESULTS: We found no significant difference in the fiber type proportion or mean fiber size between McArdle patients and controls in the biceps brachii or vastus lateralis muscles. CONCLUSIONS: No alterations in muscle fiber type proportion or size were found on muscle histology of patients with McArdle disease. Future research should focus on assessment of muscle fiber contractility to investigate the functional impairment. Muscle Nerve 55: 916-918, 2017.


Assuntos
Doença de Depósito de Glicogênio Tipo V/patologia , Fibras Musculares Esqueléticas , Adolescente , Adulto , Idoso , Biópsia , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibras Musculares Esqueléticas/classificação , Fibras Musculares Esqueléticas/patologia , Fibras Musculares Esqueléticas/fisiologia , Adulto Jovem
9.
Proc Natl Acad Sci U S A ; 113(39): 10759-68, 2016 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-27638214

RESUMO

For half a century, the process of economic integration of the Amazon has been based on intensive use of renewable and nonrenewable natural resources, which has brought significant basin-wide environmental alterations. The rural development in the Amazonia pushed the agricultural frontier swiftly, resulting in widespread land-cover change, but agriculture in the Amazon has been of low productivity and unsustainable. The loss of biodiversity and continued deforestation will lead to high risks of irreversible change of its tropical forests. It has been established by modeling studies that the Amazon may have two "tipping points," namely, temperature increase of 4 °C or deforestation exceeding 40% of the forest area. If transgressed, large-scale "savannization" of mostly southern and eastern Amazon may take place. The region has warmed about 1 °C over the last 60 y, and total deforestation is reaching 20% of the forested area. The recent significant reductions in deforestation-80% reduction in the Brazilian Amazon in the last decade-opens up opportunities for a novel sustainable development paradigm for the future of the Amazon. We argue for a new development paradigm-away from only attempting to reconcile maximizing conservation versus intensification of traditional agriculture and expansion of hydropower capacity-in which we research, develop, and scale a high-tech innovation approach that sees the Amazon as a global public good of biological assets that can enable the creation of innovative high-value products, services, and platforms through combining advanced digital, biological, and material technologies of the Fourth Industrial Revolution in progress.


Assuntos
Agricultura , Mudança Climática , Conservação dos Recursos Naturais , Brasil , Florestas , Geografia , Produto Interno Bruto , Atividades Humanas , Humanos , Internacionalidade , Transpiração Vegetal/fisiologia , Fatores de Risco , Estações do Ano
10.
Genet Med ; 18(11): 1128-1135, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-26913921

RESUMO

PURPOSE: McArdle disease is a metabolic disorder caused by pathogenic mutations in the PYGM gene. Timely diagnosis can sometimes be difficult with direct genomic analysis, which requires additional studies of cDNA from muscle transcripts. Although the "nonsense-mediated mRNA decay" (NMD) eliminates tissue-specific aberrant transcripts, there is some residual transcription of tissue-specific genes in virtually all cells, such as peripheral blood mononuclear cells (PBMCs). METHODS: We studied a subset of the main types of PYGM mutations (deletions, missense, nonsense, silent, or splicing mutations) in cDNA from easily accessible cells (PBMCs) in 12 McArdle patients. RESULTS: Analysis of cDNA from PBMCs allowed detection of all mutations. Importantly, the effects of mutations with unknown pathogenicity (silent and splicing mutations) were characterized in PBMCs. Because the NMD mechanism does not seem to operate in nonspecific cells, PBMCs were more suitable than muscle biopsies for detecting the pathogenicity of some PYGM mutations, notably the silent mutation c.645G>A (p.K215=), whose effect in the splicing of intron 6 was unnoticed in previous muscle transcriptomic studies. CONCLUSION: We propose considering the use of PBMCs for detecting mutations that are thought to cause McArdle disease, particularly for studying their actual pathogenicity.Genet Med 18 11, 1128-1135.


Assuntos
Glicogênio Fosforilase Muscular/sangue , Doença de Depósito de Glicogênio Tipo V/sangue , Doença de Depósito de Glicogênio Tipo V/genética , Patologia Molecular/métodos , Adolescente , Adulto , Códon sem Sentido/genética , Feminino , Glicogênio Fosforilase Muscular/genética , Doença de Depósito de Glicogênio Tipo V/patologia , Humanos , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Splicing de RNA/genética , Deleção de Sequência/genética , Adulto Jovem
11.
Biol Open ; 3(12): 1224-7, 2014 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-25432515

RESUMO

Patients suffering from glycogen storage disease V (McArdle disease) were shown to have higher surface electrical activity in their skeletal muscles when exercising at the same intensity as their healthy counterparts, indicating more muscle fibre recruitment. To explain this phenomenon, this study investigated whether muscle fibre type is shifted towards a predominance in type I fibres as a consequence of the disease. Muscle biopsies from the Biceps brachii (BB) (n = 9) or Vastus lateralis (VL) (n = 8) were collected over a 13-year period from male and female patients diagnosed with McArdle disease, analysed for myosin heavy chain (MHC) isoform content using SDS-PAGE, and compared to healthy controls (BB: n = 3; VL: n = 10). All three isoforms were expressed and no difference in isoform expression in VL was found between the McArdle patients and healthy controls (MHC I: 33±19% vs. 43±7%; MHC IIa: 52±9% vs. 40±7%; MHC IIx: 15±18% vs. 17±9%). Similarly, the BB isoform content was also not different between the two groups (MHC I: 33±14% vs. 30±11%; MHC IIa: 46±17% vs. 39±5%; MHC IIx: 21±13% vs. 31±14%). In conclusion, fibre type distribution does not seem to explain the higher surface EMG in McArdle patients. Future studies need to investigate muscle fibre size and contractility of McArdle patients.

12.
Acta méd. colomb ; 39(4): 300-301, oct.-dic. 2014. ilus, tab
Artigo em Espanhol | LILACS, COLNAL | ID: lil-734932

RESUMO

Objetivo: describir la evolución clínica en términos de complicaciones, calidad de vida y mortalidad de pacientes adultos mayores en un programa de diálisis crónica. Material y métodos: estudio descriptivo de tipo prospectivo, en el cual participaron 52 pacientes mayores de 65 años, quienes ingresaron a terapia dialítica en dos unidades renales de la ciudad de Bucaramanga, Colombia; durante los años 2011-2012. Los pacientes recibieron seguimiento durante un año desde el inicio de tratamiento de diálisis crónica. Para evaluar la evolución de la calidad de vida se aplicó el cuestionario SF-36 y la escala de Karnofsky en tres momentos, al ingreso, a los tres meses y a los 12 meses. Resultados: la edad promedio de los pacientes fue 77.2 años, de los cuales 53.8% fueron mujeres. La mortalidad general al final del seguimiento fue de 23.1%. Al final del seguimiento se observó una disminución significativa en los parámetros de salud general, vitalidad, función social y salud mental del cuestionario de calidad de vida SF36. Conclusión: a pesar del tratamiento de diálisis, la percepción general de calidad de vida no mejoró en la mayoría de los pacientes; sin embargo, y de manera paradójica si no se hace el tratamiento el deterioro en la calidad de vida pudiera ser peor.


Objective: to describe the clinical evolution in terms of complications, quality of life and mortality of elderly patients on chronic dialysis program. Materials and methods: descriptive prospective study in which 52 patients over 65, who entered chronic dialysis in two health units in the city of Bucaramanga, Colombia participated, during the years 2011-2012. Patients were followed for one year after the start of chronic dialysis treatment. To evaluate the evolution of the quality of life questionnaire SF-36 and the Karnofsky scale was applied at three points, on admission, at 3 months and at 12 months. Results: the mean age of the patients was 77.2 years, of whom 53.8% were women. Overall mortality at follow-up was 23.1%. At end of follow-up a significant decrease in the parameters of general health, vitality, social function and mental health of the quality of life questionnaire SF36 was observed. Conclusion: despite the dialysis treatment, the overall perception of quality of life did not improve in most patients; however, and paradoxically, if treatment is not done, the deterioration in quality of life could be worse.


Assuntos
Humanos , Masculino , Feminino , Idoso , Insuficiência Renal Crônica , Qualidade de Vida , Idoso , Inquéritos e Questionários , Diálise
13.
Rev Esp Salud Publica ; 88(2): 289-99, 2014.
Artigo em Espanhol | MEDLINE | ID: mdl-24914867

RESUMO

BACKGROUND: in the last years, the presence of new contaminants in water has been rising. There are only few studies which analyze such presence. The aims were to determine the occurrence of drugs of abuse and their metabolites in the influent and effluent of the Sewage Treatment Plant (STP) in Talavera de la Reina, and the River Tagus, as well as to evaluate the STP removal efficiency in the elimination of these substances and to estimate the consumption of drugs in Talavera. METHODS: whe samples were taken on June 28, 2010. The presence of 5 groups of drugs (10 drugs of abuse and 9 metabolites) was quantified. The efficiency was calculated from the percentage of reduction of the concentration in the influent and effluent of the STP. Drug consumption was calculated from influent concentrations. Using a specific methodology, based on the assumption the drugs after they are consumed and metabolized in the human body are excreted as parent compounds or metabolites. Whose metabolic pathways are known, and the amount of drug or metabolite quantified corresponds to the dose consumed. RESULTS: ten substances were detected. In all sampling points appeared: Benzoiclegonina (BE) (cocaine metabolite), ephedrine, methadone and its metabolite EDDP. The highest concentrations were of BE (239 ng/L), and THC-COOH (35 ng/L), both in influent. In the Tagus River, the highest concentrations were of BE (5.38 ng/L) and EDDP (4.4 ng/L). The STP removal efficiency was up to 80% for all substances except for methadone (which was zero) and EDDP (increasing to leave the STP). The estimated consumption shows that the most consumed substances were cannabis (1.88 grams / day) and cocaine (0.46 grams / day). CONCLUSION: the presence of drugs of abuse in River Tagus in Talavera demonstrates that these substances are not eliminated completly by STPs. Drug consumption estimate indicates that the population of Talavera mainly consumed cannabis and cocaine. Thus this methodology can complement epidemiological surveys.


Assuntos
Drogas Ilícitas/análise , Esgotos/química , Detecção do Abuso de Substâncias/métodos , Cocaína/análise , Efedrina/análise , Humanos , Metadona/análise , Projetos Piloto , Rios/química , Espanha
14.
Med Clin (Barc) ; 142(2): 70-2, 2014 Jan 21.
Artigo em Espanhol | MEDLINE | ID: mdl-24022027

RESUMO

BACKGROUND AND OBJECTIVES: Legionellosis is an uncommon cause of pneumonia in children and even more exceptionally in healthy children. The purpose of this study is to describe the procedure which led to the identification of an unusual source of legionella infection, in a healthy girl, and highlight the need to adopt preventive measures. METHODOLOGY AND RESULTS: A 4-year old girl without any risk factors was diagnosed of pneumonia caused by Legionella pneumophila serogroup 1. After investigating the environment, it was found that the source of the transmission was a home humidifier. CONCLUSIONS: Despite the fact that this equipment is classified with a low probability of spreading legionella, a lack of cleanliness and maintenance of these machines can increase the risk of transmission of the bacteria. Therefore, healthcare professionals must give adequate advice to their patients about the care of this equipment and how to use these machines properly.


Assuntos
Ar Condicionado/instrumentação , Contaminação de Equipamentos , Fômites/microbiologia , Legionella pneumophila/isolamento & purificação , Doença dos Legionários/transmissão , Nebulizadores e Vaporizadores/microbiologia , Microbiologia da Água , Aerossóis , Pré-Escolar , Feminino , Humanos , Imunocompetência , Legionella pneumophila/classificação , Doença dos Legionários/diagnóstico , Sorotipagem
15.
Arch Neurol ; 69(12): 1648-51, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22964873

RESUMO

OBJECTIVE To identify the cause of an adult-onset multisystemic disease with multiple deletions of mitochondrial DNA (mtDNA). DESIGN Case report. SETTING University hospitals. PATIENT A 65-year-old man with axonal sensorimotor peripheral neuropathy, ptosis, ophthalmoparesis, diabetes mellitus, exercise intolerance, steatohepatopathy, depression, parkinsonism, and gastrointestinal dysmotility. RESULTS Skeletal muscle biopsy revealed ragged-red and cytochrome- c oxidase-deficient fibers, and Southern blot analysis showed multiple mtDNA deletions. No deletions were detected in fibroblasts, and the results of quantitative polymerase chain reaction showed that the amount of mtDNA was normal in both muscle and fibroblasts. Exome sequencing using a mitochondrial library revealed compound heterozygous MPV17 mutations (p.LysMet88-89MetLeu and p.Leu143*), a novel cause of mtDNA multiple deletions. CONCLUSIONS In addition to causing juvenile-onset disorders with mtDNA depletion, MPV17 mutations can cause adult-onset multisystemic disease with multiple mtDNA deletions.

16.
Ann Hum Biol ; 39(2): 166-9, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22324844

RESUMO

AIM: The purpose of this study was to determine the allelic and genotypic frequency distribution of the C34T mutation in the muscle isoform of the adenosine monophosphate deaminase 1 (AMPD1) gene and of the missense substitution K153R in the myostatin (GDF8) gene in one Spanish and two North African populations. METHOD: One sample of 98 individuals was genotyped from the South of Spain (Alpujarra) and two samples from Morocco (77 Berbers and 78 Arabs). RESULTS: The frequency of the AMPD1 C34T mutation was lower in Berbers (0.071) compared with the Alpujarra cohort (0.153, p = 0.018). The GDF8 K153R substitution showed little variability among the three cohorts. CONCLUSIONS: Studies with larger cohorts and other ethnic groups are needed to corroborate that there does not exist any major variability in the genotype distribution of genes associated with muscle phenotypes in the South-Eastern Mediterranean area.


Assuntos
AMP Desaminase/genética , Frequência do Gene , Músculo Esquelético/metabolismo , Miostatina/genética , Fenótipo , Polimorfismo Genético , Estudos de Coortes , Feminino , Genótipo , Humanos , Masculino , Marrocos/epidemiologia , Força Muscular/genética , Espanha/epidemiologia
18.
Rev Esp Salud Publica ; 84(2): 137-49, 2010.
Artigo em Espanhol | MEDLINE | ID: mdl-20571716

RESUMO

In the summer of 2003 the temperatures reached were responsible for a large number of deaths in Europe. A year after this fact, many countries had implemented some sort of plan of prevention against excessive temperatures. Plans that had already shown its ability to prevent a large proportion of avoidable mortality in other latitudes. Since then, a lot of papers have been published providing new data on health effects of a heat wave, which can help increase the efficiency of these prevention plans. Knowing the weather conditions at risk, defining "heat wave" or to take into account the time that the plan should be active from the study of the relationship between temperature and their effects on health, to identify weather patterns that modulate the relationship between temperature and mortality, locate the profile of people at risk or to develop protocols for action as accurately as possible and based on scientific knowledge are elements drawn from studies carried on in recent years that should be taken into account.


Assuntos
Calor Extremo , Transtornos de Estresse por Calor/prevenção & controle , Humanos , Sistemas de Informação
19.
J Mater Sci Mater Med ; 19(1): 369-75, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17607514

RESUMO

Metallic transfer from implants does not stop at surrounding tissues, and metallic elements may be transferred by proteins to become lodged in organs far from the implant. This work presents an in vivo study of metallic implant corrosion to measure metallic element accumulation in organs located far from the implant, such as kidneys, livers, lungs and spleens. The studied metallic implant materials were CoCr alloy, Ti, and the experimental alloy MA956 coated with alpha-alumina. The implants were inserted in the hind legs of Wistar rats. Analysis for Co, Cr, Ti and Al metallic traces was performed after a long exposure time of 12 months by Inductively Coupled Plasma (ICP) with Mass Spectrometry (MS). According to the results, the highest Cr and Ti concentrations were detected in spleens. Co is mainly found in kidneys, since this element is eliminated via urine. Cr and Ti traces increased significantly in rat organs after the long implantation time. The organs of rats implanted with the alpha-alumina coated experimental MA956 did not present any variation in Al content after 12 months, which means there was no degradation of the alumina layer surface.


Assuntos
Rim/metabolismo , Fígado/metabolismo , Pulmão/metabolismo , Próteses e Implantes , Baço/metabolismo , Oligoelementos/análise , Alumínio/análise , Animais , Cromo/análise , Cobalto/análise , Espectrometria de Massas/métodos , Metais/análise , Metais/química , Ratos , Ratos Wistar , Titânio/análise
20.
Hum Mutat ; 29(2): 277-83, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17994553

RESUMO

Nearly 35% of all mutations identified in the muscle glycogen phosphorylase gene (PYGM) in patients with McArdle disease result in premature termination codons (PTCs), particularly the p.R50X mutation. The latter accounts for more than 50% of the mutated alleles in most Caucasian patient populations. Mutations resulting in PTC could trigger the degradation of mRNA through a mechanism known as nonsense mediated decay (NMD). To investigate if NMD affects the levels of transcripts containing PYGM mutations, 28 Spanish patients with McArdle disease, harboring 17 different mutations with PTCs in 77% of their alleles, were studied. Transcripts levels of PYGM were measured and sequenced. We assessed that 92% of patients showed NMD. The most frequent mutation (p.R50X) elicited decay in all the genotypes tested. Other PTC producing mutations resulting in NMD were: p.L5VfsX22, p.Q73HfsX7, p.E125X, p.N134KfsX161, p.W388SfsX34, p.R491AfsX7, and p.D534VfsX5. Located in the last exon, the mutation p.E797VfsX19 was not affected by NMD. Missense mutations did not appear to be affected by NMD. In the cDNA sequences they appeared as homozygous, despite being heterozygous in the genomic DNA sequences. Exceptions to the rules governing NMD were found in the mutations p.A704 V and p.K754NfsX49.


Assuntos
Códon sem Sentido/genética , Glicogênio Fosforilase Muscular/genética , Doença de Depósito de Glicogênio Tipo V/enzimologia , Doença de Depósito de Glicogênio Tipo V/genética , Estabilidade de RNA/genética , Análise Mutacional de DNA , Eletroforese em Gel de Ágar , Perfilação da Expressão Gênica , Humanos , Mutação/genética , Transcrição Gênica
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