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1.
Mol Genet Genomic Med ; 12(3): e2274, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38348603

RESUMO

Wiedemann-Rautenstrauch Syndrome (WRS; MIM 264090) is an extremely rare and highly heterogeneous syndrome that is inherited in a recessive fashion. The patients have hallmark features such as prenatal and postnatal growth retardation, short stature, a progeroid appearance, hypotonia, facial dysmorphology, hypomyelination leukodystrophy, and mental impairment. Biallelic disease-causing variants in the RNA polymerase III subunit A (POLR3A) have been associated with WRS. Here, we report the first identified cases of WRS syndrome with novel phenotypes in three consanguineous families (two Omani and one Saudi) characterized by biallelic variants in POLR3A. Using whole-exome sequencing, we identified one novel homozygous missense variant (NM_007055: c.2456C>T; p. Pro819Leu) in two Omani families and one novel homozygous variant (c.1895G>T; p Cys632Phe) in Saudi family that segregates with the disease in the POLR3A gene. In silico homology modeling of wild-type and mutated proteins revealed a substantial change in the structure and stability of both proteins, demonstrating a possible effect on function. By identifying the homozygous variants in the exon 14 and 18 of the POLR3A gene, our findings will contribute to a better understanding of the phenotype-genotype relationship and molecular etiology of WRS syndrome.


Assuntos
Progéria , Gravidez , Feminino , Humanos , Fenótipo , Progéria/genética , Retardo do Crescimento Fetal/genética , Mutação de Sentido Incorreto , Síndrome , RNA Polimerase III/genética
2.
Curr Protoc ; 3(8): e857, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37540795

RESUMO

Understanding how a gene variant affects protein function is important in life science, as it helps explain traits or dysfunctions in organisms. In a clinical setting, this understanding makes it possible to improve and personalize patient care. Bioinformatic tools often only assign a pathogenicity score, rather than providing information about the molecular basis for phenotypes. Experimental testing can furnish this information, but this is slow and costly and requires expertise and equipment not available in a clinical setting. Conversely, mapping a gene variant onto the three-dimensional (3D) protein structure provides a fast molecular assessment free of charge. Before 2021, this type of analysis was severely limited by the availability of experimentally determined 3D protein structures. Advances in artificial intelligence algorithms now allow confident prediction of protein structural features from sequence alone. The aim of the protocols presented here is to enable non-experts to use databases and online tools to investigate the molecular effect of a genetic variant. The Basic Protocol relies only on the online resources AlphaFold, Protein Structure Database, and UniProt. Alternate Protocols document the usage of the Protein Data Bank, SWISS-MODEL, ColabFold, and PyMOL for structure-based variant analysis. © 2023 The Authors. Current Protocols published by Wiley Periodicals LLC. Basic Protocol: 3D Mapping based on UniProt and AlphaFold Alternate Protocol 1: Using experimental models from the PDB Alternate Protocol 2: Using information from homology modeling with SWISS-MODEL Alternate Protocol 3: Predicting 3D structures with ColabFold Alternate Protocol 4: Structure visualization and analysis with PyMOL.


Assuntos
Inteligência Artificial , Proteínas , Modelos Moleculares , Proteínas/química , Proteínas/genética , Algoritmos , Bases de Dados de Proteínas
3.
Medicina (B.Aires) ; 83(3): 384-393, ago. 2023. graf
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1506692

RESUMO

Resumen Introducción: La monoartritis aguda (MA) represen ta una causa relevante de morbilidad que requiere de atención médica oportuna: El estudio del líquido sino vial constituye un elemento clave para su diagnóstico. El objetivo del estudio fue determinar la frecuencia y características clínicas-analíticas de los episodios de MA y bursitis agudas valoradas en un hospital durante un período de 6 años. Métodos: Estudio analítico retrospectivo de corte transversal en un hospital de Córdoba, Argentina. Se identificaron todos los episodios de monoartritis y bur sitis agudas que ocurrieron en pacientes de ≥18 años entre 2012 y 2017. Se excluyeron los cuadros de MA en embarazadas y las monoartritis crónicas. Resultados: Se incluyeron 180 episodios de MA y 12 de bursitis aguda. Entre las MA, 120 (66.7%) ocurrieron en hombres, la edad promedio fue 62.1±16.9 años. La principal causa de MA fue séptica, identificándose 70 (36%) casos, seguida la secundaria a microcristales con 54 episodios (28%) que correspondieron 27 (14%) a MA por gota y 27 (14%) a MA por depósitos de pirofosfato de calcio dihidratado (CPPD). Se identificaron cristales de urato monosódico en 26 (14.3%) pacientes, CPPD en 28 (15.6%) y de colesterol en 1 (0.6%). Discusión: La principal causa de MA fue séptica, seguida de la secundaria a microcristales (gota y secun daria a CPPD). La principal articulación afectada fue la rodilla, seguida del hombro. El análisis del líquido sino vial fue un elemento clave a la hora de poder realizar el diagnóstico diferencial entre las distintas causas de monoartritis aguda y bursitis.


Abstract Introduction: Acute monoarthritis (AM) represents a relevant cause of morbidity that requires prompt medical care. The study of synovial fluid becomes re levant to allow a rapid diagnostic approach. The main objective of the study was to determine the frequency and clinical-analytical characteristics of episodes of AM and acute bursitis evaluated in a hospital during a period of 6 years. Methods: Cross-sectional retrospective analytical study in a hospital at Córdoba, Argentina. All episodes of acute monoarthritis and bursitis that occurred in patients aged 18 years or older between 2012 and 2017 were included. AM in pregnant women and chronic monoarthritis were excluded. Results: One hundred and eighty episodes of AM and 12 of acute bursitis were included. Among the AM, 120 (66.7%) occurred in male patients and the average age was 62.1±16.9 years. The main cause of AM was septic, identifying 70 (36%) cases, followed by microcrystalline AM identify 54 (28%) cases, which corresponded to gout and calcium pyrophosphate dihydrate (CPPD) with 27 (14%) cases each one. Monosodium urate crystals were identified in 26 (14.3%) patients, CPPD in 28 (15.6%) and cholesterol in 1 (0.6%). Discussion: The main cause of AM was septic arthri tis, followed by microcrystalline AM (gout and secondary to CPPD). The main affected joint was the knee, followed by the shoulder. Synovial fluid analysis was a key ele ment when making the differential diagnosis between the different causes of acute monoarthritis and bursitis.

4.
Medicina (B Aires) ; 83(3): 384-393, 2023.
Artigo em Espanhol | MEDLINE | ID: mdl-37379535

RESUMO

INTRODUCTION: Acute monoarthritis (AM) represents a relevant cause of morbidity that requires prompt medical care. The study of synovial fluid becomes relevant to allow a rapid diagnostic approach. The main objective of the study was to determine the frequency and clinical-analytical characteristics of episodes of AM and acute bursitis evaluated in a hospital during a period of 6 years. METHODS: Cross-sectional retrospective analytical study in a hospital at Córdoba, Argentina. All episodes of acute monoarthritis and bursitis that occurred in patients aged 18 years or older between 2012 and 2017 were included. AM in pregnant women and chronic monoarthritis were excluded. RESULTS: One hundred and eighty episodes of AM and 12 of acute bursitis were included. Among the AM, 120 (66.7%) occurred in male patients and the average age was 62.1±16.9 years. The main cause of AM was septic, identifying 70 (36%) cases, followed by microcrystalline AM identify 54 (28%) cases, which corresponded to gout and calcium pyrophosphate dihydrate (CPPD) with 27 (14%) cases each one. Monosodium urate crystals were identified in 26 (14.3%) patients, CPPD in 28 (15.6%) and cholesterol in 1 (0.6%). DISCUSSION: The main cause of AM was septic arthritis, followed by microcrystalline AM (gout and secondary to CPPD). The main affected joint was the knee, followed by the shoulder. Synovial fluid analysis was a key element when making the differential diagnosis between the different causes of acute monoarthritis and bursitis.


Introducción: La monoartritis aguda (MA) representa una causa relevante de morbilidad que requiere de atención médica oportuna: El estudio del líquido sinovial constituye un elemento clave para su diagnóstico. El objetivo del estudio fue determinar la frecuencia y características clínicas-analíticas de los episodios de MA y bursitis agudas valoradas en un hospital durante un período de 6 años. Métodos: Estudio analítico retrospectivo de corte transversal en un hospital de Córdoba, Argentina. Se identificaron todos los episodios de monoartritis y bursitis agudas que ocurrieron en pacientes de =18 años entre 2012 y 2017. Se excluyeron los cuadros de MA en embarazadas y las monoartritis crónicas. Resultados: Se incluyeron 180 episodios de MA y 12 de bursitis aguda. Entre las MA, 120 (66.7%) ocurrieron en hombres, la edad promedio fue 62.1±16.9 años. La principal causa de MA fue séptica, identificándose 70 (36%) casos, seguida la secundaria a microcristales con 54 episodios (28%) que correspondieron 27 (14%) a MA por gota y 27 (14%) a MA por depósitos de pirofosfato de calcio dihidratado (CPPD). Se identificaron cristales de urato monosódico en 26 (14.3%) pacientes, CPPD en 28 (15.6%) y de colesterol en 1 (0.6%). Discusión: La principal causa de MA fue séptica, seguida de la secundaria a microcristales (gota y secundaria a CPPD). La principal articulación afectada fue la rodilla, seguida del hombro. El análisis del líquido sinovial fue un elemento clave a la hora de poder realizar el diagnóstico diferencial entre las distintas causas de monoartritis aguda y bursitis.


Assuntos
Bursite , Gota , Gravidez , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Retrospectivos , Estudos Transversais , Gota/diagnóstico , Pirofosfato de Cálcio/análise , Hospitais
5.
Genes (Basel) ; 13(12)2022 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-36553519

RESUMO

Heterozygous pathogenic variants in DNM1 are linked to an autosomal dominant form of epileptic encephalopathy. Recently, homozygous loss-of-function variants in DNM1 were reported to cause an autosomal recessive form of developmental and epileptic encephalopathy in unrelated patients. Here, we investigated a singleton from a first-degree cousin marriage who presented with facial dysmorphism, global developmental delay, seizure disorder, and nystagmus. To identify the involvement of any likely genetic cause, diagnostic clinical exome sequencing was performed. Comprehensive filtering revealed a single plausible candidate variant in DNM1. Sanger sequencing of the trio, the patient, and her parents, confirmed the full segregation of the variant. The variant is a deletion leading to a premature stop codon and is predicted to cause a protein truncation. Structural modeling implicated a complete loss of function of the Dynamin 1 (DNM1). Such mutation is predicted to impair the nucleotide binding, dimer formation, and GTPase activity of DNM1. Our study expands the phenotypic spectrum of pathogenic homozygous loss-of-function variants in DNM1.


Assuntos
Epilepsia Generalizada , Epilepsia , Feminino , Humanos , Dinamina I/genética , Epilepsia/genética , Homozigoto , Mutação
6.
Cells ; 11(19)2022 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-36231115

RESUMO

The genetic architecture of mitochondrial disease continues to expand and currently exceeds more than 350 disease-causing genes. Bi-allelic variants in RTN4IP1, also known as Optic Atrophy-10 (OPA10), lead to early-onset recessive optic neuropathy, atrophy, and encephalopathy in the afflicted patients. The gene is known to encode a mitochondrial ubiquinol oxidoreductase that interacts with reticulon 4 and is thought to be a mitochondrial antioxidant NADPH oxidoreductase. Here, we describe two unrelated consanguineous families from the northern region of Saudi Arabia harboring a missense variant (RTN4IP1:NM_032730.5; c.475G

Assuntos
Encefalopatias , Atrofia Óptica , Antioxidantes , Proteínas de Transporte/genética , Humanos , Proteínas Mitocondriais/genética , Mutação/genética , NADP/genética , Atrofia Óptica/genética , Oxirredutases/genética , Arábia Saudita
7.
Chem Commun (Camb) ; 57(69): 8608-8611, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34369500

RESUMO

Ni4O4 cubanes [(µ3-L1O)NiCl(MeOH)]4 (1) and [(µ3-L2O)NiCl(H2O)]4 (2) (L1OH = 1-H-2-benzimidazolylmethanol, L2OH = 1-methyl-2-benzimidazolylmethanol) self-assemble from commercially available 1-H- and 1-methyl-2-benzimidazolylmethanol and NiCl2·6H2O in high yields under mild conditions. Both complexes were characterised spectroscopically and by X-ray crystallography. The cubanes oxidise water electrocatalytically to dioxygen at neutral pH in aqueous potassium phosphate buffer solutions.

8.
Clin Rheumatol ; 34(5): 929-33, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25425494

RESUMO

UNLABELLED: The objective of the study was to evaluate work disability and its main associated factors in patients with early arthritis. Argentine Consortium for Early Arthritis (CONAART) is the first early arthritis cohort in Argentina. Patients with one or more swollen joints and less than 2 years of symptoms duration were followed up prospectively in 13 departments of rheumatology. Social, demographic, familiar, clinical, and laboratory data were recollected. At first year and every year, X-rays of hands and feet were performed and working status and pharmaco-economic data were recollected. Work status (employed, unemployed, retired) and type of work were assessed by direct interview using a predesigned questionnaire. Eight hundred forty-eight patients were included, rheumatoid arthritis (RA) = 483 (57 %)and undifferentiated arthritis (UA) = 365 (43 %), 694 (81.8 %) were women, median age was 46 years (interquartile range (IQR) 35-55.7) and median symptoms duration 7 months (IQR 3-12). Patients with RA had significantly higher disease activity, worse functional capacity and quality of life, and more severe radiological damage compared to UA patients. However work disability (unemployed patient) was comparable between groups (RA = 21 % versus UA = 18.6 % p = NS). In both groups, unemployed patients had higher disease activity score of 28 joints (DAS28), worse Health Assessment Questionnaire (HAQ) values, and less years of formal education (p value <0.005 in all comparisons). Radiological damage was greater in unemployed patients but this difference did not reach statistical significance. In multivariate analysis, disease activity was the main variable associated with unemployment in both groups. Joint involvement was the main cause of work disability in this cohort of patients with early arthritis, independently of the final diagnosis. KEY MESSAGES: 1. Work disability is higher in patients with inflammatory arthritis as compared to the general population. 2. Prevalence of work disability is comparable among patients with undifferentiated and rheumatoid arthritis. 3. Disease activity is the main disease variable associated with work disability.


Assuntos
Artrite Reumatoide/epidemiologia , Articulações do Pé/diagnóstico por imagem , Articulação da Mão/diagnóstico por imagem , Desemprego/estatística & dados numéricos , Adulto , Argentina , Artrite/diagnóstico por imagem , Artrite/epidemiologia , Artrite Reumatoide/diagnóstico por imagem , Estudos de Coortes , Avaliação da Deficiência , Escolaridade , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Radiografia , Índice de Gravidade de Doença , Inquéritos e Questionários
9.
J Nucl Med ; 53(5): 709-15, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22492732

RESUMO

UNLABELLED: (18)F-FDG metabolic tumor volume (MTV) and total glycolytic activity (TGA) have been proposed as potential prognostic imaging markers for patient outcome in human solid tumors. The purpose of this study was to establish whether MTV and TGA add prognostic information to clinical staging in patients with oral and oropharyngeal squamous cell carcinomas (SCCs). METHODS: The Institutional Review Board approved this Health Insurance Portability and Accountability Act-compliant single-institution retrospective study. Forty-five patients with histologically proven oral or oropharyngeal SCC underwent PET/CT for initial cancer staging and were included in the study. MTV was measured using a gradient-based method (PET Edge) and fixed-threshold methods at 38%, 50%, and 60% of maximum standardized uptake value (SUV). The TGA is defined as MTV × mean SUV. Bland-Altman analysis was used to establish the reliability of the methods of segmentation. Outcome endpoints were overall survival (OS) and progression-free survival. Cox proportional hazards univariate and multivariate regression analyses were performed. RESULTS: In Cox regression models, MTV and TGA were the only factors significantly associated with survival outcome after adjusting for all other covariates including American Joint Committee on Cancer (AJCC) stage, with hazards ratio of 1.06 (95% confidence interval, 1.01-1.10; P = 0.006) and 1.00 (95% confidence interval, 1.00-1.01; P = 0.02). The model fit was significantly better when MTV was added to AJCC stage in model I (χ(2) value change, 1.16-6.71; P = 0.01) and when TGA was added to AJCC stage in model II (χ(2) value change, 1.16-4.37; P = 0.04). The median cutoff point of 7.7 mL for primary tumor MTV was predictive of time to OS (log rank P = 0.04). The median cutoff point of 55 g for PET Edge primary tumor TGA was predictive of time to OS (log rank P = 0.08), though the result was not statistically significant. CONCLUSION: Gradient-based segmentations of primary tumor MTV and TGA are potential (18)F-FDG markers for time to survival in patients with oral and oropharyngeal SCC and may provide prognostic information in addition to AJCC stage. These exploratory imaging markers need validation in larger cohort studies.


Assuntos
Fluordesoxiglucose F18/metabolismo , Glicólise , Neoplasias Bucais/patologia , Neoplasias de Células Escamosas/metabolismo , Neoplasias Orofaríngeas/patologia , Carga Tumoral , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/diagnóstico , Neoplasias Bucais/metabolismo , Análise Multivariada , Estadiamento de Neoplasias , Neoplasias de Células Escamosas/diagnóstico , Neoplasias de Células Escamosas/patologia , Neoplasias Orofaríngeas/diagnóstico , Neoplasias Orofaríngeas/metabolismo , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
10.
BMC Cancer ; 8: 149, 2008 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-18507821

RESUMO

BACKGROUND: In the present study we analyze, in patients with breast cancer, the tumor expression of androgen receptors (AR), its relationship with clinicopathological characteristics and with the expression of several matrix metalloproteases (MMPs) and their inhibitors (TIMPs), as well as with prognosis. METHODS: An immunohistochemical study was performed using tissue microarrays and specific antibodies against AR, MMPs -1, -2, -7, -9, -11, -13, -14, and TIMPs -1, -2 and -3. More than 2,800 determinations on tumor specimens from 111 patients with primary invasive ductal carcinoma of the breast (52 with axillary lymph node metastases and 59 without them) and controls were performed. Staining results were categorized using a score based on the intensity of the staining and a specific software program calculated the percentage of immunostained cells automatically. RESULTS: A total of 83 cases (74.8%) showed a positive immunostaining for AR, but with a wide variation in the staining score values. There were no significant associations between the total immunostaining scores for AR and any clinicopathological parameters. However, score values for MMP-1, -7 and -13, were significantly higher in AR-positive tumors than in AR-negative tumors. Likewise, when we considered the cellular type expressing each factor, we found that AR-positive tumors had a higher percentage of cases positive for MMP-1, -7, -11, and TIMP-2 in their malignant cells, as well as for MMP-1 in intratumoral fibroblasts. On the other hand, multivariate analysis demonstrated that patients with AR-positive tumors have a significant longer overall survival than those with AR-negative breast carcinomas (p = 0.03). CONCLUSION: Our results confirm that AR are commonly expressed in breast cancer, and are correlated with the expression of some MMPs and TIMP-2. Although we found a specific value of AR expression to be a prognostic indicator in breast cancer, the functional role of AR in these neoplasms is still unclear and further data are needed in order to clarify their biological signification in breast cancer.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Metaloproteases/biossíntese , Receptores Androgênicos/biossíntese , Neoplasias da Mama/patologia , Neoplasias da Mama/fisiopatologia , Carcinoma Ductal de Mama/patologia , Carcinoma Ductal de Mama/fisiopatologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Metástase Linfática , Prognóstico , Análise Serial de Proteínas , Análise de Sobrevida , Inibidores Teciduais de Metaloproteinases/biossíntese
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