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1.
Nat Genet ; 56(4): 585-594, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38553553

RESUMO

We performed whole-genome sequencing (WGS) in 327 children with cerebral palsy (CP) and their biological parents. We classified 37 of 327 (11.3%) children as having pathogenic/likely pathogenic (P/LP) variants and 58 of 327 (17.7%) as having variants of uncertain significance. Multiple classes of P/LP variants included single-nucleotide variants (SNVs)/indels (6.7%), copy number variations (3.4%) and mitochondrial mutations (1.5%). The COL4A1 gene had the most P/LP SNVs. We also analyzed two pediatric control cohorts (n = 203 trios and n = 89 sib-pair families) to provide a baseline for de novo mutation rates and genetic burden analyses, the latter of which demonstrated associations between de novo deleterious variants and genes related to the nervous system. An enrichment analysis revealed previously undescribed plausible candidate CP genes (SMOC1, KDM5B, BCL11A and CYP51A1). A multifactorial CP risk profile and substantial presence of P/LP variants combine to support WGS in the diagnostic work-up across all CP and related phenotypes.


Assuntos
Paralisia Cerebral , Variações do Número de Cópias de DNA , Humanos , Criança , Variações do Número de Cópias de DNA/genética , Paralisia Cerebral/genética , Mutação , Sequenciamento Completo do Genoma , Genômica
2.
EBioMedicine ; 101: 105027, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38418263

RESUMO

BACKGROUND: Cardiomyopathy is a clinically and genetically heterogeneous heart condition that can lead to heart failure and sudden cardiac death in childhood. While it has a strong genetic basis, the genetic aetiology for over 50% of cardiomyopathy cases remains unknown. METHODS: In this study, we analyse the characteristics of tandem repeats from genome sequence data of unrelated individuals diagnosed with cardiomyopathy from Canada and the United Kingdom (n = 1216) and compare them to those found in the general population. We perform burden analysis to identify genomic and epigenomic features that are impacted by rare tandem repeat expansions (TREs), and enrichment analysis to identify functional pathways that are involved in the TRE-associated genes in cardiomyopathy. We use Oxford Nanopore targeted long-read sequencing to validate repeat size and methylation status of one of the most recurrent TREs. We also compare the TRE-associated genes to those that are dysregulated in the heart tissues of individuals with cardiomyopathy. FINDINGS: We demonstrate that tandem repeats that are rarely expanded in the general population are predominantly expanded in cardiomyopathy. We find that rare TREs are disproportionately present in constrained genes near transcriptional start sites, have high GC content, and frequently overlap active enhancer H3K27ac marks, where expansion-related DNA methylation may reduce gene expression. We demonstrate the gene silencing effect of expanded CGG tandem repeats in DIP2B through promoter hypermethylation. We show that the enhancer-associated loci are found in genes that are highly expressed in human cardiomyocytes and are differentially expressed in the left ventricle of the heart in individuals with cardiomyopathy. INTERPRETATION: Our findings highlight the underrecognized contribution of rare tandem repeat expansions to the risk of cardiomyopathy and suggest that rare TREs contribute to ∼4% of cardiomyopathy risk. FUNDING: Government of Ontario (RKCY), The Canadian Institutes of Health Research PJT 175329 (RKCY), The Azrieli Foundation (RKCY), SickKids Catalyst Scholar in Genetics (RKCY), The University of Toronto McLaughlin Centre (RKCY, SM), Ted Rogers Centre for Heart Research (SM), Data Sciences Institute at the University of Toronto (SM), The Canadian Institutes of Health Research PJT 175034 (SM), The Canadian Institutes of Health Research ENP 161429 under the frame of ERA PerMed (SM, RL), Heart and Stroke Foundation of Ontario & Robert M Freedom Chair in Cardiovascular Science (SM), Bitove Family Professorship of Adult Congenital Heart Disease (EO), Canada Foundation for Innovation (SWS, JR), Canada Research Chair (PS), Genome Canada (PS, JR), The Canadian Institutes of Health Research (PS).


Assuntos
Cardiomiopatias , Cardiopatias Congênitas , Humanos , Adulto , Cardiopatias Congênitas/genética , Sequências de Repetição em Tandem/genética , Metilação de DNA , Cardiomiopatias/genética , Ontário , Proteínas do Tecido Nervoso/genética
3.
Aesthet Surg J ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38243582

RESUMO

BACKGROUND: Musculoskeletal pain is a common occupational health problem among surgeons that can affect work productivity and quality of life. OBJECTIVES: Study the prevalence and causes of back pain among rhinoplasty surgeons, evaluate their routine practice, and identify unique risk factors. Furthermore, it seeks to measure functional disabilities using the Total Disability Index (TDI) questionnaire. METHODS: A structured online questionnaire was distributed to plastic surgeons performing rhinoplasty internationally. The questionnaire comprised sections on biodata, routine practice posture, length of practice, surgical duration and history of surgery or hospitalization related to these issues. In the second part of the survey, participants were asked to complete the TDI questionnaire. RESULTS: The prevalence of back pain was reported by 93.6% of surgeons, with low back pain being the most common (76.7%). The average pain intensity for low back pain was 44.8±26.8. The mean TDI score was calculated as 31±12.1, with 58.2% of surgeons experiencing mild-to-moderate disability. Significant associations were found between musculoskeletal pain severity and disability index and factors such as BMI, exercise, years of rhinoplasty practice, number of surgeries performed per week, and average procedure length. Interestingly, only 16.4% of rhinoplasty surgeons had prior ergonomic training or education. CONCLUSIONS: Musculoskeletal issues related to the spine are prevalent among rhinoplasty surgeons. It is imperative to educate surgeons about this underestimated health problem, provide proper physical rehabilitation targeting ergonomic concerns, and make changes to current practices to address this issue effectively.

4.
J Clin Pathol ; 76(2): 73-75, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36600573

RESUMO

The partner and localiser of BRCA2 (PALB2) gene, located on chromosome 16, functions as a tumour suppressor that plays a critical role in homologous recombination repair after DNA double-strand breaks. It encodes proteins involved in the BRCA2 and BRCA1, and RAD51 pathways. Heterozygous germline mutations in PALB2 have been implicated in the development of breast, pancreatic and ovarian cancers. Whereas biallelic mutations of PALB2 have been associated with Fanconi anaaemia. Currently, 604 distinct PALB2 variants have been discovered. However, only 140 variants are thought to be pathogenic and approximately 400 are variants of unknown significance. Further studies are needed before the presence of PLAB2 mutations can be implemented as a routine clinical biomarker.


Assuntos
Neoplasias da Mama , Proteínas Supressoras de Tumor , Feminino , Humanos , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas Nucleares/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Proteína BRCA1/genética , Reparo do DNA , Mutação , Neoplasias da Mama/genética , Predisposição Genética para Doença
5.
Cell ; 185(23): 4409-4427.e18, 2022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36368308

RESUMO

Fully understanding autism spectrum disorder (ASD) genetics requires whole-genome sequencing (WGS). We present the latest release of the Autism Speaks MSSNG resource, which includes WGS data from 5,100 individuals with ASD and 6,212 non-ASD parents and siblings (total n = 11,312). Examining a wide variety of genetic variants in MSSNG and the Simons Simplex Collection (SSC; n = 9,205), we identified ASD-associated rare variants in 718/5,100 individuals with ASD from MSSNG (14.1%) and 350/2,419 from SSC (14.5%). Considering genomic architecture, 52% were nuclear sequence-level variants, 46% were nuclear structural variants (including copy-number variants, inversions, large insertions, uniparental isodisomies, and tandem repeat expansions), and 2% were mitochondrial variants. Our study provides a guidebook for exploring genotype-phenotype correlations in families who carry ASD-associated rare variants and serves as an entry point to the expanded studies required to dissect the etiology in the ∼85% of the ASD population that remain idiopathic.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Humanos , Transtorno do Espectro Autista/genética , Predisposição Genética para Doença , Variações do Número de Cópias de DNA/genética , Genômica
6.
Cureus ; 14(2): e22669, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35386174

RESUMO

Lichen planus is an autoimmune inflammatory disease that can be associated with infections, drugs, and vaccines. Recently, it has been reported to occur following mRNA-based COVID-19 vaccines, particularly the Pfizer/BioNTech vaccine. We present the first reported case of lichen planus that developed after five days following the administration of the first dose of the Oxford-AstraZeneca vaccine in a 46-year-old healthy male. The skin eruption was purple, ill-defined, non-scaly, itchy, and distributed over his face, abdomen, back, and legs. The clinical appearance of the skin eruption and histopathology confirmed the diagnosis of lichen planus. The skin lesions were not responding well to topical steroid and oral antihistamine treatment. Thus, the patient was commenced on systemic hydroxychloroquine. The mechanism of lichen planus development following the administration of COVID-19 vaccines is unclear and needs more investigations and explanations. Healthcare providers should be aware of this possible adverse reaction following the administration of different severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccines. The histopathological features of lichen planus in our case are different from those found in the lichenoid drug eruption. This finding indicates different pathophysiology that needs further investigation.

7.
Circ Genom Precis Med ; 14(4): e003410, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34328347

RESUMO

BACKGROUND: Tetralogy of Fallot (TOF)-the most common cyanotic heart defect in newborns-has evidence of multiple genetic contributing factors. Identifying variants that are clinically relevant is essential to understand patient-specific disease susceptibility and outcomes and could contribute to delineating pathomechanisms. METHODS: Using a clinically driven strategy, we reanalyzed exome sequencing data from 811 probands with TOF, to identify rare loss-of-function and other likely pathogenic variants in genes associated with congenital heart disease. RESULTS: We confirmed a major contribution of likely pathogenic variants in FLT4 (VEGFR3 [vascular endothelial growth factor receptor 3]; n=14) and NOTCH1 (n=10) and identified 1 to 3 variants in each of 21 other genes, including ATRX, DLL4, EP300, GATA6, JAG1, NF1, PIK3CA, RAF1, RASA1, SMAD2, and TBX1. In addition, multiple loss-of-function variants provided support for 3 emerging congenital heart disease/TOF candidate genes: KDR (n=4), IQGAP1 (n=3), and GDF1 (n=8). In total, these variants were identified in 63 probands (7.8%). Using the 26 composite genes in a STRING protein interaction enrichment analysis revealed a biologically relevant network (P=3.3×10-16), with VEGFR2 (vascular endothelial growth factor receptor 2; KDR) and NOTCH1 (neurogenic locus notch homolog protein 1) representing central nodes. Variants associated with arrhythmias/sudden death and heart failure indicated factors that could influence long-term outcomes. CONCLUSIONS: The results are relevant to precision medicine for TOF. They suggest considerable clinical yield from genome-wide sequencing, with further evidence for KDR (VEGFR2) as a congenital heart disease/TOF gene and for VEGF (vascular endothelial growth factor) and Notch signaling as mechanisms in human disease. Harnessing the genetic heterogeneity of single gene defects could inform etiopathogenesis and help prioritize novel candidate genes for TOF.


Assuntos
Predisposição Genética para Doença , Mapas de Interação de Proteínas , Tetralogia de Fallot/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Recém-Nascido , Masculino , Sequenciamento do Exoma
8.
Int J Hosp Manag ; 98: 103037, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36540853

RESUMO

The COVID-19 pandemic has delivered one of the worst economic shocks in modern history and the hospitality sector has been severely affected. Since small businesses from the hospitality sector are known to be relatively more susceptible to the economic complications arising from a crisis, we explore the underlying factors and management practices that influence their continuity of operations as they continue to struggle with the on-going COVID-19 crisis in Pakistan. Using a phenomenological approach, in-depth interviews were conducted to comprehend the experiences of owners-managers. The findings show that government support, cordial relationships with stakeholders, self-determination of entrepreneurs and formal planning are the most crucial factors that shaped the immediate adjustments of operational activities in response to COVID-19. These resilient practices are hygiene concerns, increased promotion through social media, innovative marketing practices (e.g., revised offerings), operational cost-cutting and employee training to comply with changing standard operating procedures from the government and industry. The practical and theoretical implications are also discussed.

9.
Ecancermedicalscience ; 14: 1114, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33144882

RESUMO

BACKGROUND: Cytochromes P450 (CYPs) constitute an enzyme family involved in the oxidative metabolism of a wide variety of endogenous and exogenous compounds, including anti-cancer drugs and carcinogens. Unlike other human CYPs, CYP4Z1 is highly expressed in human breast carcinoma and is associated with poor prognosis. As a result, CYP4Z1 was hypothesised to be a potential biomarker or drug target for the discovery and development of promising anti-cancer therapies. MATERIALS AND METHODS: CYP4Z1 expression was immunohistochemically studied in a set of 100 different human tissues, including normal, benign, malignant and metastatic tissues, which originated from 27 anatomical sites. As a tumour model for CYP4Z1 expression, a panel of different breast cancers was evaluated for CYP4Z1 expression and its relation to histopathological features and prognostic immunohistochemical markers. RESULTS: The immunohistochemical results revealed that CYP4Z1 was expressed in only one (4.3%) of the normal tissues from the mammary glands, while the expression of the enzyme was positive in 1 (11%), 12 (19%) and 2 (40%) of the benign, malignant and metastatic tissues, respectively. Interestingly, several tumour entities showed prominent expressions of CYP4Z1, including carcinomas of adrenal cortex, squamous cells of oesophagus, lung and cervix, as well as seminoma, astrocytoma, melanoma and lastly endometrial adenocarcinoma. In breast cancers, CYP4Z1 was expressed in 82% of the cases. Its expression was significantly associated with the pathology of tumour, histological grade and status of lymph node metastasis. Importantly, it was also significantly associated with the expressions of Her2, P53 and Ki-67. CONCLUSION: These findings greatly support future plans for the use of CYP4Z1 as a biomarker or target for anti-cancer drugs. However, large-scale validation studies are needed to better delineate the potential use of CYP4Z1 for therapeutic purposes.

10.
Nature ; 586(7827): 80-86, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32717741

RESUMO

Tandem DNA repeats vary in the size and sequence of each unit (motif). When expanded, these tandem DNA repeats have been associated with more than 40 monogenic disorders1. Their involvement in disorders with complex genetics is largely unknown, as is the extent of their heterogeneity. Here we investigated the genome-wide characteristics of tandem repeats that had motifs with a length of 2-20 base pairs in 17,231 genomes of families containing individuals with autism spectrum disorder (ASD)2,3 and population control individuals4. We found extensive polymorphism in the size and sequence of motifs. Many of the tandem repeat loci that we detected correlated with cytogenetic fragile sites. At 2,588 loci, gene-associated expansions of tandem repeats that were rare among population control individuals were significantly more prevalent among individuals with ASD than their siblings without ASD, particularly in exons and near splice junctions, and in genes related to the development of the nervous system and cardiovascular system or muscle. Rare tandem repeat expansions had a prevalence of 23.3% in children with ASD compared with 20.7% in children without ASD, which suggests that tandem repeat expansions make a collective contribution to the risk of ASD of 2.6%. These rare tandem repeat expansions included previously undescribed ASD-linked expansions in DMPK and FXN, which are associated with neuromuscular conditions, and in previously unknown loci such as FGF14 and CACNB1. Rare tandem repeat expansions were associated with lower IQ and adaptive ability. Our results show that tandem DNA repeat expansions contribute strongly to the genetic aetiology and phenotypic complexity of ASD.


Assuntos
Transtorno do Espectro Autista/genética , Expansão das Repetições de DNA/genética , Genoma Humano/genética , Genômica , Sequências de Repetição em Tandem/genética , Feminino , Fatores de Crescimento de Fibroblastos/genética , Predisposição Genética para Doença , Humanos , Inteligência/genética , Proteínas de Ligação ao Ferro/genética , Masculino , Miotonina Proteína Quinase/genética , Motivos de Nucleotídeos , Polimorfismo Genético
11.
Diagnostics (Basel) ; 10(7)2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32635179

RESUMO

Helicobacter pylori (H. pylori) can cause gastritis, peptic ulcer diseases and gastric carcinoma. Endoscopy as the gold standard method of diagnosis is an invasive procedure that might not be suitable in all scenarios. Therefore, this first study in Jordan aimed to assess the non-invasive 13C urea breath test (UBT) and stool antigen test for diagnosis of H. pylori infection and the successfulness of eradication therapy as alternatives for endoscopy. Hence, a total of 30 patients attending the endoscopy units at Alkarak teaching hospital were asked to complete a questionnaire with demographic and clinical data. They were then tested for H. pylori using 13C UBT and H. pylori stool antigen before having endoscopy. Another 30 patients who were positive for H. pylori by endoscopy were tested using both tests 6 weeks post eradication therapy. Results showed that the rate of H. pylori detection using endoscopy was 56.7% (17/30). Heartburns (82.3%, p value = 0.019), epigastric pain (88.2%, p value = 0.007) and vomiting (70.5%, p value = 0.02) were the most significant symptoms. Family history of peptic ulcer diseases was significantly associated with an increased risk for having a H. pylori positive result (p value = 0.02). Compared to endoscopy, the sensitivity of 13C UBT for the diagnosis of H. pylori was 94.1% (16/17), while it was 76.5% (13/17) for the stool antigen test. The specificity of both tests was equal (76.9%). However, the positive predictive and negative predictive values (84.2% and 90.9%) for 13C UBT were higher than those (81.3% and 71.4%) for the stool antigen test. The accuracy of 13C UBT was 86.7% compared to 76.7% for the stool antigen test. There was an 87% agreement (20 patients out of 23) between both tests when used to assess success of the eradication therapy. In conclusion, the 13C UBT was found to be more sensitive and accurate than the stool antigen test when used for diagnosis; furthermore, it has a comparable outcome to the stool antigen test in assessing the successfulness of the eradication treatment.

12.
PLoS One ; 15(6): e0232043, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32542007

RESUMO

BACKGROUND: Elevated neutrophil-lymphocyte ratio (NLR) is linked to poor overall survival (OS) in pancreatic cancer. We aim to investigate the association of the various hematologic markers, in particular NLR among others, with distant metastases, a common feature in pancreatic cancer. METHODS: Clinical data from 355 pancreatic cancer patients managed at King Hussein Cancer Center (Amman-Jordan) have been reviewed. We examined the relationship between absolute neutrophil count (ANC), absolute lymphocyte count (ALC), absolute eosinophilic count (AEC), absolute monocytic count (AMC), NLR, monocyte to lymphocyte ratio (MLR) and platelet to lymphocyte ratio (PLR) with the presence of baseline distant metastases and OS. Receiver Operating Characteristic (ROC) curve analysis was plotted to identify the NLR optimum cutoff value indicative of its association with distant metastases. RESULTS: On univariate and multivariate analyses patients whom on presentation had high NLR (≥3.3) showed more baseline distant metastases compared to patients with low NLR (<3.3), (p-value: <0.0001 and <0.0001, respectively). Patients with high baseline ANC (≥5500/µL), AMC (≥600/µL), MLR (≥0.3) had more baseline distant metastases in comparison to patients with lower values (p-value: 0.02, 0.001, and <0.0001, respectively). High ANC, NLR, MLR, and PLR and low ALC were associated with poorer OS, (p-value: <0.0001, <0.0001, <0.0001, 0.04, and 0.01, respectively). CONCLUSION: This study presents additional evidence of the association of some of the hematologic markers; in particular ANC, NLR, AMC, and MLR, with baseline distant metastases and poor outcome in pancreatic cancer. Whether these immune phenomena can help in identifying patients at higher risk for the subsequent development of distant metastases is unknown.


Assuntos
Linfócitos/citologia , Neutrófilos/citologia , Neoplasias Pancreáticas/patologia , Idoso , Área Sob a Curva , Contagem de Células Sanguíneas , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Neoplasias Pancreáticas/imunologia , Neoplasias Pancreáticas/mortalidade , Curva ROC , Estudos Retrospectivos
13.
Medicina (Kaunas) ; 56(4)2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32218372

RESUMO

Background and Objectives: The goal of this study was to evaluate the clinical sonographic evaluation of postmenopausal bleeding (PMB) followed by diagnostic and/or therapeutic hysteroscopy and guided biopsy in Jordanian hospitals. Materials and Methods: A retrospective multi-centric study was performed in hospitals in Al-Karak and Amman from 2014-2016. The study recruited 189 cases to evaluate the aetiology of postmenopausal bleeding. Atrophic endometrium was observed as a major cause of postmenopausal bleeding according to histopathology. The cases were also distributed according to parity in which nulliparous patients were observed. Results: Hysteroscopy was observed to be effective for the diagnosis of postmenopausal bleeding. Conclusion: There is a need to assess more approaches for the diagnosis of postmenopausal bleeding among women.


Assuntos
Histeroscopia/instrumentação , Biópsia Guiada por Imagem/métodos , Pós-Menopausa/fisiologia , Adulto , Feminino , Hospitais/estatística & dados numéricos , Humanos , Histeroscopia/métodos , Jordânia , Pessoa de Meia-Idade , Gravidez , Estudos Retrospectivos , Ultrassonografia/métodos , Ultrassonografia/tendências , Hemorragia Uterina/diagnóstico , Hemorragia Uterina/fisiopatologia
14.
J Gastrointest Oncol ; 10(3): 529-536, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31183204

RESUMO

BACKGROUND: High neutrophil-lymphocyte ratio (NLR) is associated with poor overall survival (OS) in gastric cancer. This study evaluates whether NLR, in addition to other parameters including absolute neutrophil count (ANC), absolute lymphocyte count (ALC), absolute eosinophil count (AEC), absolute monocyte count (AMC), monocyte-lymphocyte ratio (MLR), and platelet-lymphocyte ratio (PLR) are associated with distant metastases, a common and poor prognostic feature of gastric cancer. METHODS: Clinical data from 502 gastric cancer patients treated at King Hussein Cancer Center (Amman, Jordan) have been retrospectively reviewed. We examined the association between ANC, ALC, AEC, AMC, NLR, MLR and PLR with the baseline distant metastases and OS. Receiver operating characteristic (ROC) curve analysis was utilized to determine the optimal NLR cutoff value for association with distant metastases. RESULTS: Univariate and multivariate analyses showed that patients with high baseline NLR (≥3.9) had more distant metastases on presentation than patients with low NLR (<3.9), (P value: 0.0001 and 0.0005, respectively). Furthermore, patients with high baseline ANC (≥6,015/µL), AEC (≥215/µL), PLR (≥0.15) had more distant metastases in comparison to patients with low baseline ANC (<6,015/µL), AEC (<215/µL), PLR (<0.15) (P value: 0.024, 0.001, and 0.001, respectively). High ANC, NLR, MLR and PLR are associated with poor OS (P value: 0.046, 0.0003, 0.027, and <0.0001, respectively). CONCLUSIONS: High ANC, AEC, NLR, and PLR are associated with distant metastases on presentation in gastric cancer. In the era of cancer immunotherapy, whether these immune phenomena predict the response of gastric cancer to immunotherapy is unknown.

15.
PLoS One ; 10(4): e0124189, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25831123

RESUMO

BACKGROUND: Xanthine oxidoreductase (XOR) is involved in oxidative metabolism of purines and is a source of reactive oxygen species (ROS). As such, XOR has been implicated in oxidant-mediated injury in multiple cardiopulmonary diseases. XOR enzyme activity is regulated, in part, via a phosphorylation-dependent, post-translational mechanism, although the kinase(s) responsible for such hyperactivation are unknown. METHODS AND RESULTS: Using an in silico approach, we identified a cyclin-dependent kinase 5 (CDK5) consensus motif adjacent to the XOR flavin adenine dinucleotide (FAD) binding domain. CDK5 is a proline-directed serine/threonine kinase historically linked to neural development and injury. We tested the hypothesis that CDK5 and its activators are mediators of hypoxia-induced hyperactivation of XOR in pulmonary microvascular endothelial cells (EC) and the intact murine lung. Using complementary molecular and pharmacologic approaches, we demonstrated that hypoxia significantly increased CDK5 activity in EC. This was coincident with increased expression of the CDK5 activators, cyclin-dependent kinase 5 activator 1 (CDK5r1 or p35/p25), and decreased expression of the CDK5 inhibitory peptide, p10. Expression of p35/p25 was necessary for XOR hyperactivation. Further, CDK5 physically associated with XOR and was necessary and sufficient for XOR phosphorylation and hyperactivation both in vitro and in vivo. XOR hyperactivation required the target threonine (T222) within the CDK5-consensus motif. CONCLUSIONS AND SIGNIFICANCE: These results indicate that p35/CDK5-mediated phosphorylation of T222 is required for hypoxia-induced XOR hyperactivation in the lung. Recognizing the contribution of XOR to oxidative injury in cardiopulmonary disease, these observations identify p35/CDK5 as novel regulators of XOR and potential modifiers of ROS-mediated injury.


Assuntos
Hipóxia Celular/fisiologia , Quinase 5 Dependente de Ciclina/metabolismo , Fosfotransferases/metabolismo , Xantina Desidrogenase/metabolismo , Animais , Linhagem Celular , Quinase 5 Dependente de Ciclina/genética , Flavina-Adenina Dinucleotídeo/metabolismo , Pulmão/metabolismo , Fosfotransferases/genética , Estrutura Terciária de Proteína , Interferência de RNA , RNA Interferente Pequeno , Ratos , Espécies Reativas de Oxigênio/metabolismo
16.
Am J Respir Cell Mol Biol ; 51(1): 94-103, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24490973

RESUMO

Cigarette smoke (CS) is the most common cause of chronic obstructive pulmonary diseases (COPD), including emphysema. CS exposure impacts all cell types within the airways and lung parenchyma, causing alveolar tissue destruction through four mechanisms: (1) oxidative stress; (2) inflammation; (3) protease-induced degradation of the extracellular matrix; and (4) enhanced alveolar epithelial and endothelial cell (EC) apoptosis. Studies in human pulmonary ECs demonstrate that macrophage migration inhibitory factor (MIF) antagonizes CS-induced apoptosis. Here, we used human microvascular ECs, an animal model of emphysema (mice challenged with chronic CS), and patient serum samples to address both the capacity of CS to alter MIF expression and the effects of MIF on disease severity. We demonstrate significantly reduced serum MIF levels in patients with COPD. In the murine model, chronic CS exposure resulted in decreased MIF mRNA and protein expression in the intact lung. MIF deficiency (Mif(-/-)) potentiated the toxicity of CS exposure in vivo via increased apoptosis of ECs, resulting in enhanced CS-induced tissue remodeling. This was linked to MIF's capacity to protect against double-stranded DNA damage and suppress p53 expression. Taken together, MIF appears to antagonize CS-induced toxicity in the lung and resultant emphysematous tissue remodeling by suppressing EC DNA damage and controlling p53-mediated apoptosis, highlighting a critical role of MIF in EC homeostasis within the lung.


Assuntos
Dano ao DNA/efeitos dos fármacos , Oxirredutases Intramoleculares/fisiologia , Pulmão/patologia , Fatores Inibidores da Migração de Macrófagos/fisiologia , Doença Pulmonar Obstrutiva Crônica/etiologia , Enfisema Pulmonar/etiologia , Fumaça/efeitos adversos , Animais , Apoptose/efeitos dos fármacos , Western Blotting , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/patologia , Humanos , Técnicas Imunoenzimáticas , Inflamação/etiologia , Inflamação/metabolismo , Inflamação/patologia , Pulmão/efeitos dos fármacos , Pulmão/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Estresse Oxidativo , Doença Pulmonar Obstrutiva Crônica/metabolismo , Doença Pulmonar Obstrutiva Crônica/patologia , Enfisema Pulmonar/metabolismo , Enfisema Pulmonar/patologia , Proteína Supressora de Tumor p53/metabolismo
17.
Am J Respir Cell Mol Biol ; 50(5): 932-41, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24304496

RESUMO

Apoptosis is a key pathologic feature in acute lung injury. Animal studies have demonstrated that pathways regulating apoptosis are necessary in the development of acute lung injury, and that activation of p38 mitogen-activated protein kinase (MAPK) is linked to the initiation of the apoptotic cascade. In this study, we assessed the role of the MAPK-activated protein kinase (MK) 2, one of p38 MAPK's immediate downstream effectors, in the development of apoptosis in an animal model of LPS-induced pulmonary vascular permeability. Our results indicate that wild-type (WT) mice exposed to LPS demonstrate increased apoptosis, as evidenced by cleavage of caspase 3 and poly (ADP-ribose) polymerase 1 and increased deoxynucleotidyl transferase-mediated dUDP nick-end labeling staining, which is accompanied by increases in markers of vascular permeability. In contrast, MK2(-/-) mice are protected from pulmonary vascular permeability and apoptosis in response to LPS. Although there was no difference in activation of caspase 3 in MK2(-/-) compared with WT mice, interestingly, cleaved caspase 3 translocated to the nucleus in WT mice while it remained in the cytosol of MK2(-/-) mice in response to LPS. In separate experiments, LPS-induced apoptosis in human lung microvascular endothelial cells was also associated with nuclear translocation of cleaved caspase 3 and apoptosis, which were both prevented by MK2 silencing. In conclusion, our data suggest that MK2 plays a critical role in the development of apoptosis and pulmonary vascular permeability, and its effects on apoptosis are in part related to its ability to regulate nuclear translocation of cleaved caspase 3.


Assuntos
Apoptose/fisiologia , Caspase 3/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Pulmão/irrigação sanguínea , Proteínas Serina-Treonina Quinases/metabolismo , Transporte Ativo do Núcleo Celular , Animais , Permeabilidade Capilar , Células Cultivadas , Endotélio Vascular/citologia , Endotélio Vascular/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Poli(ADP-Ribose) Polimerases
18.
Free Radic Biol Med ; 60: 336-46, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23380026

RESUMO

Cigarette smoke (CS) exposure is unquestionably the most frequent cause of emphysema in the United States. Accelerated pulmonary endothelial cell (EC) apoptosis is an early determinant of lung destruction in emphysema. One of the pathogenic causes of emphysema is an alveolar oxidant and antioxidant imbalance. The enzyme xanthine oxidoreductase (XOR) has been shown to be a source of reactive oxygen species (ROS) in a multitude of diseases (S. Sakao et al., FASEB J.21, 3640-3652; 2007). The contribution of XOR to CS-induced apoptosis is not well defined. Here we demonstrate that C57/bl6 mice exposed to CS have increased pulmonary XOR activity and protein levels compared to filtered-air-exposed controls. In addition, we demonstrate that primary pulmonary human lung microvascular endothelial cells exposed to cigarette smoke extract undergo increased rates of caspase-dependent apoptosis that are reliant on XOR activity, ROS production, and p53 function/expression. We also demonstrate that exogenous XOR is sufficient to increase p53 expression and induce apoptosis, suggesting that XOR is an upstream mediator of p53 in CS-induced EC apoptosis. Furthermore, we show that XOR activation results in DNA double-strand breaks that activate the enzyme ataxia telangiectasia mutated, which phosphorylates histone H2AX and upregulates p53. In conclusion, CS increases XOR expression, and the enzyme is both sufficient and necessary for p53 induction and CS-induced EC apoptosis.


Assuntos
Células Endoteliais/metabolismo , Enfisema Pulmonar/metabolismo , Fumar/efeitos adversos , Xantina Desidrogenase/metabolismo , Animais , Apoptose/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Células Endoteliais/citologia , Células Endoteliais/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Fosforilação/efeitos dos fármacos , Enfisema Pulmonar/enzimologia , Enfisema Pulmonar/patologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo
19.
Int J Rheum Dis ; 15(2): 136-43, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22462416

RESUMO

AIM: To estimate the prevalence of rheumatic diseases in Lebanon and to explore their distribution by geographic location, age, and gender. METHOD: Using the Community Oriented Program for the Control of Rheumatic Diseases (COPCORD) methodology, a random sample of 3530 individuals aged 15 and above was interviewed from the six Lebanese governorates. Positive respondents were evaluated by rheumatologists using the internationally accepted classification criterion of the American College of Rheumatology for the diagnosis of rheumatic diseases. RESULTS: Prevalence rates of current and past musculoskeletal problems were 24.4% and 8.4%, respectively. Shoulder (14.3%), knee (14.2%) and back (13.6%) were the most common pain sites. Point prevalence of rheumatic diseases was 15.0%. The most frequent types of rheumatic diseases were of mechanical origin, namely soft tissue rheumatism (5.8%) and osteoarthritis (4.0%). Rheumatoid arthritis (1.0%) and spondylathropathies (0.3%) constituted the most common inflammatory diseases. Coastal areas had the lowest prevalence of all diseases except for fibromyalgia. All diseases showed an increasing prevalence pattern with age and a higher prevalence among women than men. CONCLUSION: This is the first study to give population-based estimates of rheumatic diseases in Lebanon. The high burden calls for public health attention for early detection, control and prevention of these conditions. Point prevalence of individual diseases was within the range of results from other COPCORD surveys with some variations that can be attributed to differences in methodology and geo-ethnic factors.


Assuntos
Medicina Comunitária , Doenças Reumáticas/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Entrevistas como Assunto , Líbano/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Distribuição Aleatória , Inquéritos e Questionários , Adulto Jovem
20.
BMC Med Res Methodol ; 11: 52, 2011 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-21507231

RESUMO

BACKGROUND: Currently, there is one Behçet's disease (BD) specific self reporting questionnaire developed and published in the literature, The Leeds BD-quality of life (QoL). We conducted a cross-cultural adaptation and validation of the Arabic version of the Leeds BD-QoL METHODS: A cross-sectional study was conducted among 41 consecutive patients attending rheumatology clinics at the American University of Beirut Medical Center between June and December 2007. The BD-QoL questionnaire, the Katz Index of Activities of Daily Living (ADL) and the Lawton Instrumental Activities of Daily Living (IADL) questionnaires were co-administered during the same visit, and severity scores were calculated. Cross-cultural adaptation of BD-QoL was performed using forward and backward translations of the original questionnaire. Internal consistency and test-retest reliability of the final version were determined. Exploratory Factor Analysis (EFA) was used to assess the dimensionality of the scale items. External construct validity was examined by correlating Arabic BD-QoL with the severity score, ADL and IADL. RESULTS: The 30 items of the adapted Arabic BD-QoL showed a high internal consistency (KR-20 coefficient 0.89) and test-retest reliability (Spearman's test 0.91). The convergence of all 30 items suggests that the 30-item adapted Arabic BD-QoL scale is unidimensional. BD-QoL did not correlate with any of the patients' demographics. Still, it was positively correlated with patient severity score (r 0.4, p 0.02), and IADL (but not ADL). CONCLUSIONS: This cross-cultural adaptation has produced an Arabic BD-QoL questionnaire that is now available for use in clinical settings and in research studies, among Arabic speaking patients.


Assuntos
Síndrome de Behçet/epidemiologia , Qualidade de Vida , Inquéritos e Questionários , Atividades Cotidianas , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Doenças Reumáticas/epidemiologia , Autorrelato , Índice de Gravidade de Doença
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