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1.
Proc Natl Acad Sci U S A ; 119(35): e2121251119, 2022 08 30.
Artigo em Inglês | MEDLINE | ID: mdl-35994670

RESUMO

GCN2 (general control nonderepressible 2) is a serine/threonine-protein kinase that controls messenger RNA translation in response to amino acid availability and ribosome stalling. Here, we show that GCN2 controls erythrocyte clearance and iron recycling during stress. Our data highlight the importance of liver macrophages as the primary cell type mediating these effects. During different stress conditions, such as hemolysis, amino acid deficiency or hypoxia, GCN2 knockout (GCN2-/-) mice displayed resistance to anemia compared with wild-type (GCN2+/+) mice. GCN2-/- liver macrophages exhibited defective erythrophagocytosis and lysosome maturation. Molecular analysis of GCN2-/- cells demonstrated that the ATF4-NRF2 pathway is a critical downstream mediator of GCN2 in regulating red blood cell clearance and iron recycling.


Assuntos
Aminoácidos , Eritrócitos , Ferro , Fígado , Macrófagos , Proteínas Serina-Treonina Quinases , Fator 4 Ativador da Transcrição/metabolismo , Aminoácidos/deficiência , Aminoácidos/metabolismo , Anemia/metabolismo , Animais , Citofagocitose , Eritrócitos/metabolismo , Deleção de Genes , Hemólise , Hipóxia/metabolismo , Ferro/metabolismo , Fígado/citologia , Lisossomos/metabolismo , Macrófagos/metabolismo , Camundongos , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Estresse Fisiológico
2.
Epilepsy Behav ; 155: 109771, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642529

RESUMO

INTRODUCTION: Epilepsy affects around 50 million people worldwide and is associated with lower quality of life scores, an increased risk of premature death, and significant socio-economic implications. The lack of updated evidence on current epidemiology and patient characterization creates considerable uncertainty regarding the epilepsy burden in Portugal. The study aims to characterize and quantify the epilepsy patients who have been hospitalized, with medical or surgical procedures involved, and to analyze their associated comorbidities and mortality rates. METHODS: A multicenter retrospective study was conducted using hospital production data of epilepsy patients. The study included all patients diagnosed with epilepsy-related International Classification of Diseases-9/10 codes between 2015 and 2018 in 57 Portuguese National Health Service (NHS) hospitals (n = 57 institutions). Patient characterization and quantification were done for all patients with an epilepsy diagnosis, with specific analyses focusing on those whose primary diagnosis was epilepsy. Baseline, demographic, and clinical characteristics were analyzed using descriptive statistics. RESULTS: Between 2015 and 2018, a total of 80,494 hospital episodes (i.e., patient visit that generates hospitalization and procedures) were recorded, with 18 % to 19 % directly related to epilepsy. Among these epilepsy-related hospital episodes, 13.0 % led to short term hospitalizations (less than 24 h). Additionally, the average length of stay for all these epilepsy-related episodes was 8 days. A total of 49,481 patients were identified with epilepsy based on ICD-9/10 codes. The median age of patients was 64 years (min: 0; max: 104), with a distribution of 4.8 patients per 1,000 inhabitants. From the total of deaths (9,606) between 2015 and 2018, 14% were associated with patients whose primary diagnosis was epilepsy, with 545 of these being epilepsy-related deaths. Among patients with a primary diagnosis of epilepsy, the most common comorbidities were hypertension (24%) and psychiatric-related or similar comorbidities (15%), such as alcohol dependance, depressive and major depressive disorders, dementia and other convulsions. CONCLUSION: This study showed similar results to other European countries. However, due to methodological limitations, a prospective epidemiological study is needed to support this observation. Furthermore, the present study provides a comprehensive picture of hospitalized epilepsy patients in Portugal, their comorbidities, mortality, and hospital procedures.


Assuntos
Epilepsia , Hospitalização , Humanos , Portugal/epidemiologia , Epilepsia/epidemiologia , Epilepsia/diagnóstico , Masculino , Feminino , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Idoso , Hospitalização/estatística & dados numéricos , Adolescente , Adulto Jovem , Idoso de 80 Anos ou mais , Criança , Comorbidade , Pré-Escolar , Lactente , Recém-Nascido , Tempo de Internação/estatística & dados numéricos
3.
Gut ; 72(6): 1143-1154, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36585238

RESUMO

OBJECTIVE: Colorectal cancer (CRC) is the third most diagnosed cancer, and requires surgical resection and reconnection, or anastomosis, of the remaining bowel to re-establish intestinal continuity. Anastomotic leak (AL) is a major complication that increases mortality and cancer recurrence. Our objective is to assess the causal role of gut microbiota in anastomotic healing. DESIGN: The causal role of gut microbiota was assessed in a murine AL model receiving faecal microbiota transplantation (FMT) from patients with CRC collected before surgery and who later developed or not, AL. Anastomotic healing and gut barrier integrity were assessed after surgery. Bacterial candidates implicated in anastomotic healing were identified using 16S rRNA gene sequencing and were isolated from faecal samples to be tested both in vitro and in vivo. RESULTS: Mice receiving FMT from patients that developed AL displayed poor anastomotic healing. Profiling of gut microbiota of patients and mice after FMT revealed correlations between healing parameters and the relative abundance of Alistipes onderdonkii and Parabacteroides goldsteinii. Oral supplementation with A. onderdonkii resulted in a higher rate of leaks in mice, while gavage with P. goldsteinii improved healing by exerting an anti-inflammatory effect. Patients with AL and mice receiving FMT from AL patients presented upregulation of mucosal MIP-1α, MIP-2, MCP-1 and IL-17A/F before surgery. Retrospective analysis revealed that patients with AL present higher circulating neutrophil and monocyte counts before surgery. CONCLUSION: Gut microbiota plays an important role in surgical colonic healing in patients with CRC. The impact of these findings may extend to a vast array of invasive gastrointestinal procedures.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Camundongos , Animais , Citocinas , Microbioma Gastrointestinal/fisiologia , Estudos Retrospectivos , RNA Ribossômico 16S , Anastomose Cirúrgica/efeitos adversos , Fístula Anastomótica/microbiologia , Neoplasias Colorretais/cirurgia
4.
Pediatr Res ; 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38052860

RESUMO

BACKGROUND: Glycogen storage disease type V (GSDV) is an autosomal recessive metabolic condition caused by pathogenic PYGM variants. This is an underdiagnosed condition as it presents with exercise intolerance in children. We reviewed the GSDV cases of a tertiary hospital center to assess diagnostic timing/accuracy, as well as potential clinical/analytical predictors of such factors. METHODS: We retrospectively reviewed all GSDV cases with follow-up in both Pediatric and Adult Metabolic Diseases consultations. We included 28 cases and assessed their hospital record for clinical information. RESULTS: Over 90% of our cases had late diagnoses, with more than 50% being diagnosed in adulthood despite symptom onset in preschool (very late diagnosis). Diagnostic age was lower in patients exhibiting myoglobinuria. Interestingly, patients with a positive family history of GSDV had similar rates of very late diagnoses, likely since the index case was already detected very late in life. Finally, we observe that the R50* variant is associated with increased myoglobinuria and CK elevation, in a dosage-dependent manner. CONCLUSION: We concluded that GSDV is severely underdiagnosed, and that some clinical and analytical aspects of the condition can be more indicative of this diagnosis. Furthermore, we propose for the first time a genotype-phenotype correlation in GSDV. IMPACT: GSDV is a pediatric-onset metabolic disorder that is mostly diagnosed late in the adult age and commonly misdiagnosed. We observed the first genotype-phenotype correlation in GSDV, regarding the common R50* variant. Awareness of GSDV for pediatricians and the overall medical community is vital.

5.
Am J Physiol Gastrointest Liver Physiol ; 320(4): G601-G608, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33404375

RESUMO

Butyrate is a short-chain fatty acid produced by colonic gut bacteria as a result of fermentation of dietary fibers. In the colon, butyrate is a major energy substrate and contributes to the nutritional support and proliferation of a healthy mucosa. It also promotes the intestinal barrier function by enhancing mucus production and tight junctions. In addition to its pro-proliferative effect in healthy colonocytes, butyrate inhibits the proliferation of cancer cells. The antineoplastic effect of butyrate is associated with the inhibitory effect of butyrate on histone deacetylase (HDAC) enzymes, which promote carcinogenesis. Due to the metabolic shift of cancer cells toward glycolysis, unused butyrate accumulates and inhibits procarcinogenic HDACs. In addition, recent studies suggest that butyrate may improve the healing of colonic tissue after surgery in animal models, specifically at the site of reconnection of colonic ends, anastomosis, after surgical resection. Here, we review current evidence on the impact of butyrate on epithelial integrity and colorectal cancer and present current knowledge on data that support its potential applications in surgical practice.


Assuntos
Bactérias/metabolismo , Butiratos/metabolismo , Colo/cirurgia , Neoplasias Colorretais/metabolismo , Células Epiteliais/metabolismo , Microbioma Gastrointestinal , Movimento Celular , Proliferação de Células , Colo/metabolismo , Colo/microbiologia , Colo/patologia , Neoplasias Colorretais/patologia , Metabolismo Energético , Células Epiteliais/microbiologia , Células Epiteliais/patologia , Humanos , Invasividade Neoplásica , Permeabilidade , Cicatrização
6.
BMC Microbiol ; 21(1): 259, 2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34583649

RESUMO

BACKGROUND: Oral iron supplementation is commonly prescribed for anemia and may play an important role in the gut microbiota recovery of anemic individuals who received antibiotic treatment. This study aims to investigate the effects of iron supplementation on gut microbiota recovery after antibiotics exposure. RESULTS: Mice were subjected to oral antibiotic treatment with neomycin and metronidazole and were fed diets with different concentrations of iron. The composition of the gut microbiota was followed throughout treatment by 16S rRNA sequencing of DNA extracted from fecal samples. Gut microbiota functions were inferred using PICRUSt2, and short-chain fatty acid concentration in fecal samples was assessed by liquid-chromatography mass spectrometry. Iron supplementation after antibiotic exposure shifted the gut microbiota composition towards a Bacteroidetes phylum-dominant composition. At the genus level, the iron-supplemented diet induced an increase in the abundance of Parasutterella and Bacteroides, and a decrease of Bilophila and Akkermansia. Parasutterella excrementihominis, Bacteroides vulgatus, and Alistipes finegoldii, were more abundant with the iron excess diet. Iron-induced shifts in microbiota composition were accompanied by functional modifications, including an enhancement of the biosynthesis of primary bile acids, nitrogen metabolism, cyanoamino acid metabolism and pentose phosphate pathways. Recovery after antibiotic treatment increased propionate levels independent of luminal iron levels, whereas butyrate levels were diminished by excess iron. CONCLUSIONS: Oral iron supplementation after antibiotic therapy in mice may lead to deleterious changes in the recovery of the gut microbiota. Our results have implications on the use of oral iron supplementation after antibiotic exposure and justify further studies on alternative treatments for anemia in these settings.


Assuntos
Antibacterianos/efeitos adversos , Bactérias/efeitos dos fármacos , Suplementos Nutricionais/efeitos adversos , Disbiose/induzido quimicamente , Microbioma Gastrointestinal/efeitos dos fármacos , Ferro/efeitos adversos , Animais , Bactérias/classificação , Biodiversidade , Disbiose/microbiologia , Fezes/microbiologia , Ferro/farmacologia , Camundongos
7.
BMC Cancer ; 21(1): 172, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33596864

RESUMO

BACKGROUND: Colibactin is a genotoxin that induces DNA double-strand breaks that may lead to carcinogenesis and is produced by Escherichia coli strains harboring the pks island. Human and animal studies have shown that colibactin-producing gut bacteria promote carcinogenesis and enhance the progression of colorectal cancer through cellular senescence and chromosomal abnormalities. In this study, we investigated the impact of prebiotics on the genotoxicity of colibactin-producing E. coli strains Nissle 1917 and NC101. METHODS: Bacteria were grown in medium supplemented with 20, 30 and 40 mg/mL of prebiotics inulin or galacto-oligosaccharide, and with or without 5 µM, 25 µM and 125 µM of ferrous sulfate. Colibactin expression was assessed by luciferase reporter assay for the clbA gene, essential for colibactin production, in E. coli Nissle 1917 and by RT-PCR in E. coli NC101. The human epithelial colorectal adenocarcinoma cell line, Caco-2, was used to assess colibactin-induced megalocytosis by methylene blue binding assay and genotoxicity by γ-H2AX immunofluorescence analysis. RESULTS: Inulin and galacto-oligosaccharide enhanced the expression of clbA in pks+ E. coli. However, the addition of 125 µM of ferrous sulfate inhibited the expression of clbA triggered by oligosaccharides. In the presence of either oligosaccharide, E. coli NC101 increased dysplasia and DNA double-strand breaks in Caco-2 cells compared to untreated cells. CONCLUSION: Our results suggest that, in vitro, prebiotic oligosaccharides exacerbate DNA damage induced by colibactin-producing bacteria. Further studies are necessary to establish whether oligosaccharide supplementation may lead to increased colorectal tumorigenesis in animal models colonized with pks+ E. coli.


Assuntos
Carcinogênese/patologia , Neoplasias do Colo/patologia , Dano ao DNA , Escherichia coli/metabolismo , Mutagênicos/efeitos adversos , Oligossacarídeos/farmacologia , Peptídeos/efeitos adversos , Policetídeos/efeitos adversos , Células CACO-2 , Carcinogênese/induzido quimicamente , Senescência Celular , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/genética , Ilhas Genômicas , Humanos
8.
Brain ; 143(9): 2696-2708, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32875335

RESUMO

Sarcoglycanopathies comprise four subtypes of autosomal recessive limb-girdle muscular dystrophies (LGMDR3, LGMDR4, LGMDR5 and LGMDR6) that are caused, respectively, by mutations in the SGCA, SGCB, SGCG and SGCD genes. In 2016, several clinicians involved in the diagnosis, management and care of patients with LGMDR3-6 created a European Sarcoglycanopathy Consortium. The aim of the present study was to determine the clinical and genetic spectrum of a large cohort of patients with sarcoglycanopathy in Europe. This was an observational retrospective study. A total of 33 neuromuscular centres from 13 different European countries collected data of the genetically confirmed patients with sarcoglycanopathy followed-up at their centres. Demographic, genetic and clinical data were collected for this study. Data from 439 patients from 13 different countries were collected. Forty-three patients were not included in the analysis because of insufficient clinical information available. A total of 159 patients had a confirmed diagnosis of LGMDR3, 73 of LGMDR4, 157 of LGMDR5 and seven of LGMDR6. Patients with LGMDR3 had a later onset and slower progression of the disease. Cardiac involvement was most frequent in LGMDR4. Sixty per cent of LGMDR3 patients carried one of the following mutations, either in a homozygous or heterozygous state: c.229C>T, c.739G>A or c.850C>T. Similarly, the most common mutations in LMGDR5 patients were c.525delT or c.848G>A. In LGMDR4 patients the most frequent mutation was c.341C>T. We identified onset of symptoms before 10 years of age and residual protein expression lower than 30% as independent risk factors for losing ambulation before 18 years of age, in LGMDR3, LGMDR4 and LGMDR5 patients. This study reports clinical, genetic and protein data of a large European cohort of patients with sarcoglycanopathy. Improving our knowledge about these extremely rare autosomal recessive forms of LGMD was helped by a collaborative effort of neuromuscular centres across Europe. Our study provides important data on the genotype-phenotype correlation that is relevant for the design of natural history studies and upcoming interventional trials in sarcoglycanopathies.


Assuntos
Estudos de Associação Genética , Sarcoglicanopatias/epidemiologia , Sarcoglicanopatias/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Estudos de Coortes , Europa (Continente)/epidemiologia , Feminino , Estudos de Associação Genética/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Distrofia Muscular do Cíngulo dos Membros/diagnóstico , Distrofia Muscular do Cíngulo dos Membros/epidemiologia , Distrofia Muscular do Cíngulo dos Membros/genética , Estudos Retrospectivos , Sarcoglicanopatias/diagnóstico , Adulto Jovem
9.
Immunohematology ; 36(4): 152-156, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33544621

RESUMO

CONCLUSIONS: The prevalence of blood group antigens and phenotypes varies significantly in Brazil. To ensure a proper rare blood supply, it is essential to establish a local and regional database of rare donors connected to the national registry. The objective of this study was to create a database of rare blood donors in the northern region of southern Brazil. From November 2011 to December 2018, red blood cell (RBC) phenotyping and genotyping were performed on common and high-prevalence antigens in donors and patients in southern Brazil. During this study period, 17 patients and 33 blood donors with rare phenotypes were identified. Six patients had already been alloimmunized to clinically significant antigens. Patients with the following phenotypes (i.e., negative for highprevalence antigens) were found: Yt(a-), Jk(a-b-), Lu(a-b-), Oh (Bombay), Tc(a-), k-, and Fy(a-b-). Among the donors, Kp(a+b-), Fy(a-b-), Lu(a-b-), and k- phenotypes were identified. We also found four donors with the weak D type 18 phenotype. In conclusion, we observed that the prevalence of rare blood phenotypes in our region corresponds more to the prevalence found in the Caucasian population when compared with other regions in Brazil. Our results show the importance of continuous screening for rare donors in different regions of the country and the creation of a local database to support RBC transfusions in patients who need rare blood.


Assuntos
Doadores de Sangue , Antígenos de Grupos Sanguíneos , Transfusão de Sangue , Antígenos de Grupos Sanguíneos/genética , Brasil , Humanos , Fenótipo
10.
Brain ; 141(11): 3160-3178, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30351409

RESUMO

Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels control neuronal excitability and their dysfunction has been linked to epileptogenesis but few individuals with neurological disorders related to variants altering HCN channels have been reported so far. In 2014, we described five individuals with epileptic encephalopathy due to de novo HCN1 variants. To delineate HCN1-related disorders and investigate genotype-phenotype correlations further, we assembled a cohort of 33 unpublished patients with novel pathogenic or likely pathogenic variants: 19 probands carrying 14 different de novo mutations and four families with dominantly inherited variants segregating with epilepsy in 14 individuals, but not penetrant in six additional individuals. Sporadic patients had epilepsy with median onset at age 7 months and in 36% the first seizure occurred during a febrile illness. Overall, considering familial and sporadic patients, the predominant phenotypes were mild, including genetic generalized epilepsies and genetic epilepsy with febrile seizures plus (GEFS+) spectrum. About 20% manifested neonatal/infantile onset otherwise unclassified epileptic encephalopathy. The study also included eight patients with variants of unknown significance: one adopted patient had two HCN1 variants, four probands had intellectual disability without seizures, and three individuals had missense variants inherited from an asymptomatic parent. Of the 18 novel pathogenic missense variants identified, 12 were associated with severe phenotypes and clustered within or close to transmembrane domains, while variants segregating with milder phenotypes were located outside transmembrane domains, in the intracellular N- and C-terminal parts of the channel. Five recurrent variants were associated with similar phenotypes. Using whole-cell patch-clamp, we showed that the impact of 12 selected variants ranged from complete loss-of-function to significant shifts in activation kinetics and/or voltage dependence. Functional analysis of three different substitutions altering Gly391 revealed that these variants had different consequences on channel biophysical properties. The Gly391Asp variant, associated with the most severe, neonatal phenotype, also had the most severe impact on channel function. Molecular dynamics simulation on channel structure showed that homotetramers were not conducting ions because the permeation path was blocked by cation(s) strongly complexed to the Asp residue, whereas heterotetramers showed an instantaneous current component possibly linked to deformation of the channel pore. In conclusion, our results considerably expand the clinical spectrum related to HCN1 variants to include common generalized epilepsy phenotypes and further illustrate how HCN1 has a pivotal function in brain development and control of neuronal excitability.


Assuntos
Epilepsia Generalizada/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Mutação/genética , Canais de Potássio/genética , Espasmos Infantis/genética , Adolescente , Adulto , Idoso , Animais , Células CHO , Criança , Pré-Escolar , Cricetulus , Estimulação Elétrica , Feminino , Estudos de Associação Genética , Humanos , Lactente , Masculino , Potenciais da Membrana/genética , Pessoa de Meia-Idade , Modelos Moleculares , Mutagênese Sítio-Dirigida/métodos , Adulto Jovem
11.
Clin Oral Investig ; 23(4): 1967-1976, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30238414

RESUMO

OBJECTIVE: This study aims to perform a systematic review and meta-analysis of clinical trials in order to evaluate the clinical and radiographic success rates of primary teeth pulpotomy performed with biodentine, when compared to MTA. METHODS: Search strategies were conducted in nine databases on August 5th, 2017, update on February 14th, 2018. Clinical articles were selected, which were in accordance with the inclusion and exclusion criteria and the research objective. They were analyzed by meta-analysis at three time points (6, 12, and 18 months). RESULTS: Out of the 233 publications initially identified, only 9 studies that fulfilled the inclusion criteria were included in the review. The 6-month overall clinical (RR = 0.99; 95% CI = 0.96-1.02, p = 0.92) and radiographic success rates (RR = 0.96; 95% CI = 0.92-1.00, p = 0.28) showed that biodentine vs. MTA did not differ statistically. The 12 and 18-month overall clinical success rates, respectively (RR = 1.01; 95% CI = 0.97-1.04, p = 0.77; RR = 0.98; 95% CI = 0.92-1.05, p = 0.74) and radiographic success rates, respectively (RR = 0.97; 95% CI = 0.92-1.02, p = 0.11; RR = 1.00; 95% CI = 0.91-1.10, p = 0.56) also showed that biodentine vs. MTA did not differ statistically. CONCLUSION: There is no superiority of one material over the other, MTA versus biodentine. CLINICAL RELEVANCE: This systematic review comparing the performance of biodentine in relation to the MTA when used in the pulpotomy technique in primary teeth. Although MTA is considered the gold standard material for pulpotomy procedures, it has some drawbacks (poor handling, staining potential, long setting time); thus, it is important to evaluate the clinical performance of other calcium silicate-based cements like biodentine that overcome this drawbacks.


Assuntos
Compostos de Cálcio/farmacologia , Pemetrexede/farmacologia , Pulpotomia , Silicatos/farmacologia , Dente Decíduo , Criança , Pré-Escolar , Combinação de Medicamentos , Humanos
13.
Hum Mutat ; 39(10): 1314-1337, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30055037

RESUMO

Congenital muscular dystrophy type 1A (MDC1A) is one of the main subtypes of early-onset muscle disease, caused by disease-associated variants in the laminin-α2 (LAMA2) gene. MDC1A usually presents as a severe neonatal hypotonia and failure to thrive. Muscle weakness compromises normal motor development, leading to the inability to sit unsupported or to walk independently. The phenotype associated with LAMA2 defects has been expanded to include milder and atypical cases, being now collectively known as LAMA2-related muscular dystrophies (LAMA2-MD). Through an international multicenter collaborative effort, 61 new LAMA2 disease-associated variants were identified in 86 patients, representing the largest number of patients and new disease-causing variants in a single report. The collaborative variant collection was supported by the LOVD-powered LAMA2 gene variant database (https://www.LOVD.nl/LAMA2), updated as part of this work. As of December 2017, the database contains 486 unique LAMA2 variants (309 disease-associated), obtained from direct submissions and literature reports. Database content was systematically reviewed and further insights concerning LAMA2-MD are presented. We focus on the impact of missense changes, especially the c.2461A > C (p.Thr821Pro) variant and its association with late-onset LAMA2-MD. Finally, we report diagnostically challenging cases, highlighting the relevance of modern genetic analysis in the characterization of clinically heterogeneous muscle diseases.


Assuntos
Estudos de Associação Genética , Laminina/genética , Mutação , Fenótipo , Alelos , Biomarcadores , Encéfalo/anormalidades , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Biologia Computacional/métodos , Bases de Dados de Ácidos Nucleicos , Frequência do Gene , Variação Genética , Genótipo , Humanos , Imuno-Histoquímica , Imageamento por Ressonância Magnética/métodos , Distrofias Musculares/diagnóstico , Distrofias Musculares/genética
14.
J Hum Genet ; 61(6): 497-505, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26841830

RESUMO

Congenital myopathies (CMs) are a heterogeneous group of muscle diseases characterized by hypotonia, delayed motor skills and muscle weakness with onset during the first years of life. The diagnostic workup of CM is highly dependent on the interpretation of the muscle histology, where typical pathognomonic findings are suggestive of a CM but are not necessarily gene specific. Over 20 loci have been linked to these myopathies, including three exceptionally large genes (TTN, NEB and RYR1), which are a challenge for molecular diagnosis. We developed a new approach using massive parallel sequencing (MPS) technology to simultaneously analyze 20 genes linked to CMs. Assay design was based on the Ion AmpliSeq strategy and sequencing runs were performed on an Ion PGM system. A total of 12 patients were analyzed in this study. Among the 2534 variants detected, 14 pathogenic mutations were successfully identified in the DNM2, NEB, RYR1, SEPN1 and TTN genes. Most of these had not been documented and/or fully characterized, hereby contributing to expand the CM mutational spectrum. The utility of this approach was demonstrated by the identification of mutations in 70% of the patients included in this study, which is relevant for CMs especially considering its wide phenotypic and genetic heterogeneity.


Assuntos
Estudos de Associação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Doenças Musculares/congênito , Doenças Musculares/diagnóstico , Adolescente , Adulto , Idoso , Alelos , Substituição de Aminoácidos , Biópsia , Criança , Análise Mutacional de DNA , Dinamina II/genética , Feminino , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/patologia , Mutação , Linhagem , Fenótipo , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Adulto Jovem
15.
Muscle Nerve ; 54(3): 413-21, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-26851892

RESUMO

INTRODUCTION: In this study we estimated the prevalence, incidence, and mortality of myasthenia gravis (MG) in northern Portugal and characterized the clinical features of the patients identified. METHODS: We used 2 data sources: clinical records from the hospitals and pyridostigmine prescription registers. RESULTS: On December 31, 2013, we estimated a point prevalence of 111.7 patients per million population. The highest prevalence was observed in the group >65 years of age, especially in men (288.1 per million). During 2013, we estimated an incidence rate of 6.3 per million per year. Among women, the incidence rate was highest in the 15-49-year age group; in men, incidence increased with age up to 22.1 per million in those >65 years old. The MG-related mortality rate was 0.5 per million. CONCLUSIONS: These figures are in keeping with similar studies and emphasize the importance of diagnosis and management of MG in elderly populations. Muscle Nerve 54: 413-421, 2016.


Assuntos
Miastenia Gravis/epidemiologia , Adolescente , Adulto , Distribuição por Idade , Idoso , Anticorpos/sangue , Criança , Pré-Escolar , Bases de Dados Factuais , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Exame Neurológico , Portugal/epidemiologia , Prevalência , Receptores Proteína Tirosina Quinases/imunologia , Receptores Colinérgicos/imunologia , Estudos Retrospectivos , Adulto Jovem
16.
Eur J Immunol ; 44(6): 1604-14, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24643698

RESUMO

MHC class I (MHC I) antigen presentation is a ubiquitous process by which cells present endogenous proteins to CD8(+) T lymphocytes during immune surveillance and response. Hereditary hemochromatosis protein, HFE, is involved in cellular iron uptake but, while structurally homologous to MHC I, is unable to bind peptides. However, increasing evidence suggests a role for HFE in the immune system. Here, we investigated the impact of HFE on CD8(+) T-lymphocyte activation. Using transient HFE transfection assays in a model of APCs, we show that WT HFE (HFEWT ), but not C282Y-mutated HFE, inhibits secretion of MIP-1ß from antigen-specific CD8(+) T lymphocytes. HFEWT expression also resulted in major decreases in CD8(+) T-lymphocyte activation as measured by 4-1BB expression. We further demonstrate that inhibition of CD8(+) T-lymphocyte activation was independent of MHC I surface levels, ß2-m competition, HFE interaction with transferrin receptor, antigen origin, or epitope affinity. Finally, we identified the α1-2 domains of HFEWT as being responsible for inhibiting CD8(+) T-lymphocyte activation. Our data imply a new role for HFEWT in altering CD8(+) T-lymphocyte reactivity, which could modulate antigen immunogenicity.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Ativação Linfocitária , Proteínas de Membrana/imunologia , Substituição de Aminoácidos , Linfócitos T CD8-Positivos/citologia , Regulação da Expressão Gênica/genética , Células HEK293 , Proteína da Hemocromatose , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Proteínas de Membrana/genética , Mutação de Sentido Incorreto , Estrutura Terciária de Proteína , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/genética , Membro 9 da Superfamília de Receptores de Fatores de Necrose Tumoral/imunologia
17.
J Hum Genet ; 59(8): 454-64, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25007885

RESUMO

Molecular characterization of patients with Duchenne or Becker muscular dystrophies is essential for establishing a differential diagnosis, allowing appropriate clinical follow-up, patient management and genetic counseling. In light of the recent mutation-based therapeutic approaches, DMD gene analysis has gained further relevance. Owing to the size and complexity of the DMD gene and the diversity of mutation types, molecular analysis is not always a straightforward task requiring the combination of several methodologies. Our national genetic diagnostic service genetically characterized 308 dystrophinopathy patients (284 unrelated families), leading to the identification of 175 distinct mutations, including 39 unpublished variants. These studies revealed several potential diagnostic pitfalls (because of technical limitations or related with DMD's genetic heterogeneity) that may be overlooked even considering the international disease-specific diagnostic guidelines. Comprehensive analysis involved expression studies at the mRNA level, the identification of splicing changes and ultimately providing evidence for apparent exceptions to the reading-frame rule. Besides increasing the mutation detection rate, this detailed molecular characterization is indispensable for the identification of suitable candidates for the new mutation-centered therapies. As patient registries are internationally recognized as essential for clinical trial recruitment, this led us to develop the Portuguese Duchenne and Becker Muscular Dystrophy registry in collaboration with the Translational Research in Europe-Assessment and Treatment of Neuromuscular Diseases network.


Assuntos
Distrofina/genética , Distrofia Muscular de Duchenne/genética , Criança , Pré-Escolar , Estudos de Coortes , Biologia Computacional , DNA Complementar/genética , Diagnóstico Diferencial , Europa (Continente) , Feminino , Genótipo , Humanos , Lactente , Masculino , Distrofia Muscular de Duchenne/diagnóstico , Distrofia Muscular de Duchenne/terapia , Mutação , Portugal , Prognóstico , Splicing de RNA , RNA Mensageiro/genética , Fases de Leitura , Sistema de Registros
18.
BMC Geriatr ; 14: 13, 2014 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-24484283

RESUMO

BACKGROUND: The purpose of this study was to investigate the influence of muscle mass and bone mineral density on markers of mobility in dwelling elderly women. METHODS: This cross-sectional study included 99 elderly women, who were 65 years old or above, in Campinas-SP, Brazil. To collect data, we used sociodemographic data, the body mass index (BMI), health status, comorbidities, use of medications, mobility tests (TUG and gait speed) and examinations of the body composition (densitometry with dual-emission X-ray absorptiometry "DXA"). In order to examine the relationship between muscle and bone mass with mobility (gait speed and TUG), we applied the Spearman correlation coefficient.Also was applied the analysis of covariance (ANCOVA) adjusted for age and comorbidities. To identify the factors associated with mobility, we used the univariate and multivariate logistic regression analysis. The level of significance for statistical tests was P < 0.05. RESULTS: The correlation between sarcopenia and bone mineral density with mobility tests showed a significant relationship only between sarcopenia and TUG (r = 0.277, P = 0.006) in Spearman correlation coefficient. The result of the correlation analysis (ANCOVA) showed that sarcopenia was associated with gait speed (r2 = 0.0636, P = 0.0018) and TUG (r2 = 0.0898, P = 0.0027). The results of the multivariate analysis showed that age (P = 0.034, OR = 1.081) was associated with worse performance on gait speed. By highlighting the TUG test, the results of the multivariate analysis showed that the age (P = 0.004, OR = 1.111) and BMI in overweight (P = 0.011, OR = 7.83) and obese (P < 0.001, OR = 7.84) women were associated with lower performance of the functionality of the lower limbs. CONCLUSION: The findings with regard to mobility tests which were analyzed in this study indicate the association of variables related to the aging process that contribute to the decline in physical performance, for example, age, BMI and sarcopenia.


Assuntos
Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Avaliação Geriátrica/métodos , Limitação da Mobilidade , Força Muscular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Marcha/fisiologia , Humanos , Músculo Esquelético/fisiologia
19.
Oncotarget ; 15: 562-572, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39145528

RESUMO

Colorectal cancer (CRC) is highly prevalent and is a major cause of cancer-related deaths worldwide. The incidence rate of CRC remains alarmingly high despite screening measures. The main curative treatment for CRC is a surgical resection of the diseased bowel segment. Postoperative complications usually involve a weakened gut barrier and a dissemination of bacterial proinflammatory lipopolysaccharides. Herein we discuss how gut microbiota and microbial metabolites regulate basal inflammation levels in the gut and the healing process of the bowel after surgery. We further elaborate on the restoration of the gut barrier function in patients with CRC and how this potentially impacts the dissemination and implantation of CRC cells in extracolonic tissues, contributing therefore to worse survival after surgery.


Assuntos
Neoplasias Colorretais , Microbioma Gastrointestinal , Humanos , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Neoplasias Colorretais/terapia , Animais , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiologia
20.
Gastroenterol Rep (Oxf) ; 12: goae058, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38984069

RESUMO

The prebiotic inulin has been vaunted for its potential to reduce the risk of colorectal cancer. Inulin fermentation resulting in the production of short-chain fatty acids, primarily butyrate, has been reported to be associated with properties that are beneficial for gut health and has led to an increased consumption of inulin in the Western population through processed food and over-the-counter dietary supplements. However, in clinical trials, there is limited evidence of the efficacy of inulin in preventing colorectal cancer. Moreover, recent data suggest that improper inulin consumption may even be harmful for gastro-intestinal health under certain circumstances. The main objective of this review is to provide insight into the beneficial and potentially detrimental effects of inulin supplementation in the context of colorectal cancer prevention and enhancement of treatment efficacy.

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