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1.
Br J Clin Pharmacol ; 89(11): 3340-3351, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37294011

RESUMO

AIMS: Despite the availability of newer antiseizure medications, carbamazepine (CBZ) remains the gold standard. However, patients of Asian ancestry are susceptible to CBZ-related severe cutaneous adverse reactions. Universal HLA-B*15:02 screening is a promising intervention to address this. With the increasing recognition of integrating real-world evidence in economic evaluations, the cost-effectiveness of universal HLA-B*15:02 screening was assessed using available real-world data in Malaysia. METHODS: A hybrid model of a decision tree and Markov model was developed to evaluate 3 strategies for treating newly diagnosed epilepsy among adults: (i) CBZ initiation without HLA-B*15:02 screening (current practice); (ii) universal HLA-B*15:02 screening prior to CBZ initiation; and (iii) alternative prescribing without HLA-B*15:02 screening. The model was populated with real-world inputs derived from the Malaysian population. From a societal perspective, base-case analysis and sensitivity analyses estimated the costs and outcomes over a lifetime. Incremental cost-effectiveness ratios were calculated. RESULTS: In the base-cases analysis, universal HLA-B*15:02 screening yielded the lowest total costs and the highest total quality-adjusted life years (QALYs) gained. Compared with current practice, universal screening was less costly by USD100 and more effective by QALYs increase of 0.1306, while alternative prescribing resulted in 0.1383 QALYs loss at additional costs of USD332. The highest seizure remission rate (56%) was estimated for universal HLA-B*15:02 screening vs. current practice (54%) and alternative prescribing (48%). CONCLUSION: Our study suggests that universal HLA-B*15:02 screening is a cost-effective intervention in Malaysia. With the demonstrated value of real-world evidence in economic evaluations, more relevant standardization efforts should be emphasized to better inform decision-making.


Assuntos
Análise de Custo-Efetividade , Síndrome de Stevens-Johnson , Adulto , Humanos , Benzodiazepinas/uso terapêutico , Carbamazepina/uso terapêutico , Análise Custo-Benefício , Antígenos HLA-B/genética , Antígeno HLA-B15/genética , Malásia/epidemiologia , Síndrome de Stevens-Johnson/epidemiologia
2.
Epilepsia ; 63(4): 936-949, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35170024

RESUMO

OBJECTIVE: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse drug reactions. Antiseizure medications (ASMs) with aromatic ring structure, including carbamazepine, are among the most common culprits. Screening for human leukocyte antigen (HLA) allele HLA-B*15:02 is recommended prior to initiating treatment with carbamazepine in Asians, but this allele has low positive predictive value. METHODS: We performed whole genome sequencing and analyzed 6 199 696 common variants among 113 aromatic ASM-induced SJS/TEN cases and 84 tolerant controls of Han Chinese ethnicity. RESULTS: In the primary analysis, nine variants reached genome-wide significance (p < 5e-08), one in the carbamazepine subanalysis (85 cases vs. 77 controls) and a further eight identified in HLA-B*15:02-negative subanalysis (35 cases and 53 controls). Interaction analysis between each novel variant from the primary analysis found that five increased risk irrespective of HLA-B*15:02 status or zygosity. HLA-B*15:02-positive individuals were found to have reduced risk if they also carried a chromosome 12 variant, chr12.9426934 (heterozygotes: relative risk = .71, p = .001; homozygotes: relative risk = .23, p < .001). All significant variants lie within intronic or intergenic regions with poorly understood functional consequence. In silico functional analysis of suggestive variants (p < 5e-6) identified through the primary and subanalyses (stratified by HLA-B*15:02 status and drug exposure) suggests that genetic variation within regulatory DNA may contribute to risk indirectly by disrupting the regulation of pathology-related genes. The genes implicated were specific either to the primary analysis (CD9), HLA-B*15:02 carriers (DOCK10), noncarriers (ABCA1), carbamazepine exposure (HLA-E), or phenytoin exposure (CD24). SIGNIFICANCE: We identified variants that could explain why some carriers of HLA-B*15:02 tolerate treatment, and why some noncarriers develop ASM-induced SJS/TEN. Additionally, this analysis suggests that the mixing of HLA-B*15:02 carrier status in previous studies might have masked variants contributing to susceptibility, and that inheritance of risk for ASM-induced SJS/TEN is complex, likely involving multiple risk variants.


Assuntos
Anticonvulsivantes , Síndrome de Stevens-Johnson , Anticonvulsivantes/efeitos adversos , Carbamazepina/efeitos adversos , DNA , Predisposição Genética para Doença/genética , Antígenos HLA-B/genética , Antígeno HLA-B15/genética , Humanos , Fatores de Risco , Síndrome de Stevens-Johnson/genética
3.
Int J Cancer ; 146(8): 2336-2347, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31469434

RESUMO

Nasopharyngeal carcinoma (NPC) is originated from the epithelial cells of nasopharynx, Epstein-Barr virus (EBV)-associated and has the highest incidence and mortality rates in Southeast Asia. Late presentation is a common issue and early detection could be the key to reduce the disease burden. Sensitivity of plasma EBV DNA, an established NPC biomarker, for Stage I NPC is controversial. Most newly reported NPC biomarkers have neither been externally validated nor compared to the established ones. This causes difficulty in planning for cost-effective early detection strategies. Our study systematically evaluated six established and four new biomarkers in NPC cases, population controls and hospital controls. We showed that BamHI-W 76 bp remains the most sensitive plasma biomarker, with 96.7% (29/30), 96.7% (58/60) and 97.4% (226/232) sensitivity to detect Stage I, early stage and all NPC, respectively. Its specificity was 94.2% (113/120) against population controls and 90.4% (113/125) against hospital controls. Diagnostic accuracy of BamHI-W 121 bp and ebv-miR-BART7-3p were validated. Hsa-miR-29a-3p and hsa-miR-103a-3p were not, possibly due to lower number of advanced stage NPC cases included in this subset. Decision tree modeling suggested that combination of BamHI-W 76 bp and VCA IgA or EA IgG may increase the specificity or sensitivity to detect NPC. EBNA1 99 bp could identify NPC patients with poor prognosis in early and advanced stage NPC. Our findings provided evidence for improvement in NPC screening strategies, covering considerations of opportunistic screening, combining biomarkers to increase sensitivity or specificity and testing biomarkers from single sampled specimen to avoid logistic problems of resampling.


Assuntos
Anticorpos Antivirais/sangue , DNA Viral/sangue , Herpesvirus Humano 4/isolamento & purificação , Carcinoma Nasofaríngeo/sangue , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/sangue , Neoplasias Nasofaríngeas/virologia , Biomarcadores Tumorais/sangue , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/imunologia , Estudos de Casos e Controles , Ensaio de Imunoadsorção Enzimática , Infecções por Vírus Epstein-Barr/sangue , Infecções por Vírus Epstein-Barr/virologia , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/imunologia , Humanos , MicroRNAs/sangue , Carcinoma Nasofaríngeo/patologia , Neoplasias Nasofaríngeas/patologia , Estadiamento de Neoplasias , Prognóstico
4.
Neurol Sci ; 41(3): 591-598, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31720899

RESUMO

INTRODUCTION: Genetic (idiopathic) generalized epilepsy (GGE) is a common form of epilepsy characterized by unknown aetiology and a presence of genetic component in its predisposition. METHODS: To understand the genetic factor in a family with GGE, we performed whole exome sequencing (WES) on a trio of a juvenile myoclonic epilepsy/febrile seizure (JME/FS) proband with JME/FS mother and healthy father. Sanger sequencing was carried out for validation of WES results and variant detection in other family members. RESULTS: Predictably damaging variant found in affected proband and mother but absent in healthy father in SCN1A gene was found to be associated with generalized epilepsy and febrile seizure. The novel non-synonymous substitution (c.5753C>T, p.S1918F) in SCN1A was found in all family members with GGE, of which 4/8 were JME subtypes, and/or febrile seizure, while 3 healthy family member controls did not have the mutation. This mutation was also absent in 41 GGE patients and 414 healthy Malaysian Chinese controls. CONCLUSION: The mutation is likely to affect interaction between the sodium channel and calmodulin and subsequently interrupt calmodulin-dependent modulation of the channel.


Assuntos
Epilepsia Generalizada/genética , Epilepsia Mioclônica Juvenil/genética , Canal de Sódio Disparado por Voltagem NAV1.1/genética , Convulsões Febris/genética , Adolescente , Adulto , Idoso , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Mutação , Linhagem , Sequenciamento do Exoma
5.
Int J Cancer ; 145(8): 2260-2266, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30698824

RESUMO

Nasopharyngeal carcinoma (NPC) is an epithelial cancer of the nasopharynx which is highly associated with Epstein-Barr virus (EBV). Worldwide, most of the top 20 countries with the highest incidence and mortality rates of NPC are low- and middle-income countries. Many studies had demonstrated that EBV could be detected in the tissue, serum and plasma of NPC patients. In this study, we explored the potential of assays based on non-invasive nasal washings (NW) as a diagnostic and prognostic tool for NPC. A total of 128 patients were evaluated for NW EBV DNA loads and a subset of these samples were also tested for 27 EBV and human miRNAs shortlisted from literature. EBV DNA and seven miRNAs showed area under the receiver operating characteristic curve (AUC) values of more than 0.7, suggestive of their potential utility to detect NPC. Logistic regression analyses suggested that combination of two NW assays that test for EBNA-1 and hsa-miR-21 had the best performance in detecting NPC. The trend of NW EBV DNA load matched with clinical outcome of 71.4% (10 out of 14) NPC patients being followed-up. In summary, the non-invasive NW testing panel may be particularly useful for NPC screening in remote areas where healthcare facilities and otolaryngologists are lacking, and may encourage frequent testing of individuals in the high risk groups who are reluctant to have their blood tested. However, further validation in an independent cohort is required to strengthen the utility of this testing panel as a non-invasive detection tool for NPC.


Assuntos
Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/isolamento & purificação , MicroRNAs/genética , Líquido da Lavagem Nasal/virologia , Carcinoma Nasofaríngeo/diagnóstico , Neoplasias Nasofaríngeas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , DNA Viral/genética , Detecção Precoce de Câncer/métodos , Infecções por Vírus Epstein-Barr/virologia , Feminino , Perfilação da Expressão Gênica/métodos , Herpesvirus Humano 4/genética , Herpesvirus Humano 4/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/genética , Carcinoma Nasofaríngeo/virologia , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/virologia , Nasofaringe/metabolismo , Nasofaringe/virologia , Reação em Cadeia da Polimerase/métodos , Prognóstico , Curva ROC , Adulto Jovem
6.
J Therm Biol ; 74: 14-22, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29801619

RESUMO

Heat shock response (HSR), in terms of transcription regulation of two heat shock proteins genes hsp70 and hsp90), was analysed in a widespread tropical copepod Pseudodiaptomus annandalei. The mRNA transcripts of both genes were quantified after copepods at a salinity of 20 underwent an acclimation process involving an initial acclimation temperature of 29 °C, followed by gradual thermal ramping to the target exposure temperature range of 24-36 °C. The respective cellular HSR and organismal metabolism, measured by respiratory activity at exposure temperatures, were compared. The fold change in mRNA expression for both hsp70 and hsp90 (8-9 fold) peaks at 32 °C, which is very close to 32.4 °C, the upper thermal optimum for respiration in the species. Unexpectedly, the modelled HSR curves peak at only 3 °C (hsp90) and 3.5 °C (hsp70) above the mean water temperature (29.32 °C) of the copepod in the field. We propose that copepods in tropical waters adopt a preparative HSR strategy, early at the upper limit of its thermal optimum, due to the narrow thermal range of its habitat thus precluding substantial energy demand at higher temperatures. However, the model suggests that the species could survive to at least 36 °C with short acclimation time. Nevertheless, the significant overlap between its thermal range of hsp synthesis and the narrow temperature range of its habitat also suggests that any unprecedented rise in sea temperature would have a detrimental effect on the species.


Assuntos
Aclimatação , Copépodes/metabolismo , Resposta ao Choque Térmico , Estresse Fisiológico , Temperatura , Animais , Estuários , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/metabolismo , RNA Mensageiro/metabolismo , Clima Tropical
7.
Pharmacogenet Genomics ; 27(7): 275-278, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28570299

RESUMO

The majority of the carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis CBZ-SJS/TEN are associated with HLA-B*15:02 in Asian populations where this allele is common. In contrast, the association with HLA-A*31:01 is only reported in Japanese and Europeans. This study aimed to further investigate the association with HLA-A*31:01 besides HLA-B*15:02 in a multiethnic Malaysian population. Twenty-eight CBZ-SJS/TEN cases and 227 CBZ-tolerant controls were recruited. Association was tested by comparing carrier frequencies of the alleles between cases and controls. Significant associations were detected between HLA-B*15:02 and CBZ-SJS/TEN in independent ethnic groups: Malays [P=2.00×10; odds ratio (OR): 49.0; 95% confidence interval (CI): 9.36-256.81], Chinese (P=0.0047; OR: 14.3; 95% CI: 2.38-86.03) and Indians (P=0.04; OR: 13.8; 95% CI: 1.51-124.99). Combined analysis of all ethnic groups showed a significant association with OR Cochran-Mantel-Haenszel (ORCMH) of 26.6 (95% CI: 12.80-55.25; PCMH=2.31×10). In Indians, HLA-A*31:01 was found to be associated significantly with CBZ-SJS/TEN (P=0.023; OR: 10.4; 95% CI: 1.64-65.79) and combined analyses of both variants, HLA-A*31:01 and HLA-B*15:02, increased the strength of the association (P=0.0068; OR: 14.3; 95% CI: 2.20-92.9). Besides HLA-B*15:02, our study found a new association between HLA-A*31:01 and CBZ-SJS/TEN in Indians.


Assuntos
Carbamazepina/efeitos adversos , Etnicidade/genética , Antígenos HLA-A/genética , Antígenos HLA-B/genética , Síndrome de Stevens-Johnson/etiologia , Síndrome de Stevens-Johnson/genética , Adolescente , Adulto , Idoso , Alelos , Povo Asiático/genética , Estudos de Casos e Controles , Criança , Feminino , Humanos , Malásia , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Int J Cancer ; 139(8): 1731-9, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27236004

RESUMO

Nasopharyngeal carcinoma (NPC) is an epithelial squamous cell carcinoma on the mucosal lining of the nasopharynx. The etiology of NPC remains elusive despite many reported studies. Most studies employ a single platform approach, neglecting the cumulative influence of both the genome and transcriptome toward NPC development. We aim to employ an integrated pathway approach to identify dysregulated pathways linked to NPC. Our approach combines imputation NPC GWAS data from a Malaysian cohort as well as published expression data GSE12452 from both NPC and non-NPC nasopharynx tissues. Pathway association for GWAS data was performed using MAGENTA while for expression data, GSA-SNP was used with gene p values derived from differential expression values from GEO2R. Our study identified NPC association in the gene ontology (GO) axonemal dynein complex pathway (pGWAS-GSEA = 1.98 × 10(-2) ; pExpr-GSEA = 1.27 × 10(-24) ; pBonf-Combined = 4.15 × 10(-21) ). This association was replicated in a separate cohort using gene expression data from NPC and non-NPC nasopharynx tissues (pAmpliSeq-GSEA = 6.56 × 10(-4) ). Loss of function in the axonemal dynein complex causes impaired cilia function, leading to poor mucociliary clearance and subsequently upper or lower respiratory tract infection, the former of which includes the nasopharynx. Our approach illustrates the potential use of integrated pathway analysis in detecting gene sets involved in the development of NPC in the Malaysian cohort.


Assuntos
Carcinoma/genética , Carcinoma/metabolismo , Dineínas/genética , Dineínas/metabolismo , Neoplasias Nasofaríngeas/genética , Neoplasias Nasofaríngeas/metabolismo , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Malásia , Masculino , Modelos Genéticos , Carcinoma Nasofaríngeo , Polimorfismo de Nucleotídeo Único , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , RNA Neoplásico/metabolismo , Transdução de Sinais
9.
Int J Cancer ; 136(3): 678-87, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24947555

RESUMO

Nasopharyngeal carcinoma (NPC) arises from the mucosal epithelium of the nasopharynx and is constantly associated with Epstein-Barr virus type 1 (EBV-1) infection. We carried out a genome-wide association study (GWAS) of 575,247 autosomal SNPs in 184 NPC patients and 236 healthy controls of Malaysian Chinese ethnicity. Potential association signals were replicated in a separate cohort of 260 NPC patients and 245 healthy controls. We confirmed the association of HLA-A to NPC with the strongest signal detected in rs3869062 (p = 1.73 × 10(-9)). HLA-A fine mapping revealed associations in the amino acid variants as well as its corresponding SNPs in the antigen peptide binding groove (p(HLA-A-aa-site-99) = 3.79 × 10(-8), p(rs1136697) = 3.79 × 10(-8)) and T-cell receptor binding site (p(HLA-A-aa-site-145) = 1.41 × 10(-4), p(rs1059520) = 1.41 × 10(-4)) of the HLA-A. We also detected strong association signals in the 5'-UTR region with predicted active promoter states (p(rs41545520) = 7.91 × 10(-8)). SNP rs41545520 is a potential binding site for repressor ATF3, with increased binding affinity for rs41545520-G correlated with reduced HLA-A expression. Multivariate logistic regression diminished the effects of HLA-A amino acid variants and SNPs, indicating a correlation with the effects of HLA-A*11:01, and to a lesser extent HLA-A*02:07. We report the strong genetic influence of HLA-A on NPC susceptibility in the Malaysian Chinese.


Assuntos
Antígenos HLA-A/genética , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único , Aminoácidos/análise , Povo Asiático , Carcinoma , Estudos de Coortes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Malásia , Carcinoma Nasofaríngeo
10.
Cancer Cell Int ; 14(1): 101, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25317078

RESUMO

BACKGROUND: Side population (SP) assay identifies cells with dye/drug extrusion ability, a characteristic of stem cells. Here, we determined if SP cells exist in a verified cell line originating from recurrent nasopharyngeal carcinoma (NPC) and a xenograft established from recurrent metastatic NPC. These cells were evaluated for stem-like properties via functional assays as well as for tumourigenicity. METHODS: We used Hoechst 33342 to identify the SP from non-SP (NSP) cells in HK1 NPC cell line and xeno-284 NPC xenograft. The cells were assayed for in vitro characteristics of cancer stem cells (CSC), gene expression and tumourigenicity ability. Student's t test was used to test for significance. RESULTS: Five to ten percent and less than 0.5% of HK1 and xeno-284 NPC cells, respectively, were SP cells. Fumitremorgin C (FTC), as opposed to verapamil, was effective in causing the cells to retain Hoechst 33342 dye. HK1 SP cells formed more holoclones, had more aldehyde dehydrogenase (ALDH) activity, divided asymmetrically and contained slow-proliferating cells. ABCG2, SOX2, TERT, MYC, Hedgehog, Notch, TGFß and Wnt signalling pathway genes were significantly upregulated in the SP cells. However, despite these differences in vitro, both HK1 SP and NSP cells had an overall similar tumourigenic potential in vivo. CONCLUSIONS: HK1 SP cells were ABCG2-specific as confirmed by FTC inhibition and gene expression data. Despite data from in vitro and gene expression experiments suggesting stem-like features, there was no significant difference in tumourigenic potential between SP and NSP cells. We conclude that SP assay alone is not sufficient to identify CSCs in HK1 cells. Our work also suggests the presence of a stem-cell like population among NPC cells which do not display increased tumourigenicity.

11.
Epilepsia ; 55(11): e120-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25266342

RESUMO

This study aimed to investigate the prevalence and association of HLA-B*15:02 with carbamazepine-induced Stevens-Johnson syndrome and toxic epidermal necrolysis (CBZ-SJS/TEN) in the Indian population in Malaysia, which mostly originated from Southern India. HLA-B alleles in five Indian case patients with CBZ-SJS/TEN and 52 CBZ-tolerant controls, and followed by a pooled sample of seven cases from two centers in Malaysia were analyzed. Positive association for HLA-B*15:02 with CBZ-SJS/TEN was detected in Indians (40% [2/5] vs. 3.8% [2/52], odds ratio [OR] 16.7, p = 0.0349), of which 80% (4/5) of the Indian patients originated from Southern India. A pooled sample of seven cases showed stronger association between HLA-B*15:02 and CBZ-SJS/TEN (57.1% [4/7] vs. 3.8% [2/52], OR 33.3, 95% confidence interval [CI] 4.25-162.21, p = 1.05 × 10(-3)). Subsequent meta-analysis on Indians from Malaysia and India further demonstrated a significant and strong association between HLA-B*15:02 and CBZ-SJS/TEN (OR 38.54; 95% CI 6.83-217.34, p < 1.0 × 10(-4)). Our study is the first on Indians predominantly from Southern India that demonstrated HLA-B*15:02 as a strong risk factor for CBZ-SJS/TEN despite a low population allele frequency. This stressed the importance of testing for HLA-B*15:02, irrespective of the ancestral background, including populations with low allele frequency.


Assuntos
Carbamazepina/farmacologia , Frequência do Gene/genética , Predisposição Genética para Doença , Antígeno HLA-B15/genética , Síndrome de Stevens-Johnson/epidemiologia , Síndrome de Stevens-Johnson/genética , Adolescente , Adulto , Idoso , Povo Asiático/genética , Epiderme/imunologia , Epiderme/patologia , Feminino , Antígeno HLA-B15/imunologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Necrose/imunologia , Fatores de Risco , Adulto Jovem
12.
Protein Expr Purif ; 95: 8-12, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24291446

RESUMO

This paper describes the recombinant production of a biologically active Epstein-Barr virus BZLF1 trans-activator, i.e., Z-encoded broadly reactive activator (ZEBRA), that recognized specific DNA motifs. We used auto-induction for histidine-tagged BZLF1 expression in Escherichia coli and immobilized cobalt affinity membrane chromatography for protein purification under native conditions. We obtained the purified BZLF1 at a yield of 5.4mg per gram of wet weight cells at 75% purity, in which 27% of the recombinant BZLF1 remained biologically active. The recombinant BZLF1 bound to oligonucleotides containing ZEBRA response elements, either AP-1 or ZIIIB, but not a ZIIIB mutant. The recombinant BZLF1 showed a specific DNA-binding activity which could be useful for functional studies.


Assuntos
DNA/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Transativadores/química , Transativadores/metabolismo , Cromatografia de Afinidade , DNA/química , Escherichia coli , Oligonucleotídeos/química , Oligonucleotídeos/metabolismo , Ligação Proteica , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Transativadores/genética , Transativadores/isolamento & purificação
13.
Ther Drug Monit ; 36(1): 3-9, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24342894

RESUMO

The authors describe a case of a 37-year-old Malay lady with an unusually slow carbamazepine clearance, which may be related to genetic polymorphisms of drug metabolizing enzymes and transporters. When given a small daily dose of 200 mg immediate-release carbamazepine, this patient experienced drowsiness. Subsequently, she reduced her carbamazepine dose to 200 mg twice a week (on Mondays and Fridays), resulting in poor seizure control. At the same time, the patient was diagnosed with hyperthyroidism and was given carbimazole and propranolol. Hyperthyroidism and the concurrent use of these antihyperthyroid agents may have further slowed down the metabolism of carbamazepine. Therapeutic drug monitoring of carbamazepine was carried out, and a slow carbamazepine clearance of 1.45 L·h⁻¹ per 70 kg was observed. Genotyping of selected genetic variants in CYP3A4, CYP3A5, EPHX1, ABCB1, and ABCC2 revealed that she has CYP3A5*3/*3 and ABCB1 3435-CC genotypes. Both genotypes have been shown to be associated with higher adjusted mean serum carbamazepine concentration in Chinese and Korean patients with epilepsy. Physicians should be vigilant about the risk of adverse effects among patients with a slow carbamazepine clearance, especially in Malays. Simulations of carbamazepine dosing regimen based on the pharmacokinetic parameters of this patient were performed to allow individualization of drug therapy.


Assuntos
Anticonvulsivantes/farmacocinética , Carbamazepina/farmacocinética , Epilepsia/tratamento farmacológico , Tireotoxicose/fisiopatologia , Adulto , Anticonvulsivantes/administração & dosagem , Anticonvulsivantes/uso terapêutico , Antitireóideos/uso terapêutico , Carbamazepina/administração & dosagem , Carbamazepina/uso terapêutico , Carbimazol/uso terapêutico , Relação Dose-Resposta a Droga , Monitoramento de Medicamentos , Feminino , Variação Genética , Genótipo , Humanos , Hipertireoidismo/tratamento farmacológico , Hipertireoidismo/fisiopatologia , Malásia , Adesão à Medicação , Proteína 2 Associada à Farmacorresistência Múltipla , Polimorfismo Genético , Propranolol/uso terapêutico , Tireotoxicose/tratamento farmacológico
14.
Epilepsy Res ; 189: 107070, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36584483

RESUMO

Epilepsy is a complex neurological disease that can be caused by both genetic and environmental factors. Many studies have been conducted to investigate the genetic risk variants and molecular mechanisms of epilepsy. Disruption of excitation-inhibition balance (E/I balance) is one of the widely accepted disease mechanisms of epilepsy. The maintenance of E/I balance is an intricate process that is governed by multiple proteins. Using whole exome sequencing (WES), we identified a novel GABRA1 c.448G>A (p.E150K) variant and ERBB4 c.1972A>T (p.I658F, rs190654033) variant in a Malaysian Chinese family with genetic generalized epilepsy (GGE). The GGE may be triggered by dysregulation of E/I balance mechanism. Segregation of the variants in the family was verified by Sanger sequencing. All family members with GGE inherited both variants. However, family members who carried only one of the variants did not show any symptoms of GGE. Both the GABRA1 and ERBB4 variants were predicted damaging by MutationTaster and CADD, and protein structure analysis showed that the variants had resulted in the formation of additional hydrogen bonds in the mutant proteins. GABRA1 variant could reduce the efficiency of GABAA receptors, and constitutively active ERBB4 receptors caused by the ERBB4 variant promote internalization of GABAA receptors. The interaction between the two variants may cause a greater disruption in E/I balance, which is more likely to induce a seizure. Nevertheless, this disease model was derived from a single small family, further studies are still needed to confirm the verifiability of the purported disease model.


Assuntos
Epilepsia Generalizada , Epilepsia , Humanos , Epilepsia Generalizada/genética , Epilepsia/genética , Convulsões , Família , Receptores de GABA-A/genética , Receptores de GABA-A/química , Ácido gama-Aminobutírico , Receptor ErbB-4/genética
15.
PeerJ ; 11: e16368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38047035

RESUMO

Climatic factors have commonly been attributed as the trigger of general flowering, a unique community-level mass flowering phenomenon involving most dipterocarp species that forms the foundation of Southeast Asian tropical rainforests. This intriguing flowering event is often succeeded by mast fruiting, which provides a temporary yet substantial burst of food resources for animals, particularly frugivores. However, the physiological mechanism that triggers general flowering, particularly in dipterocarp species, is not well understood largely due to its irregular and unpredictable occurrences in the tall and dense forests. To shed light on this mechanism, we employed ecological transcriptomic analyses on an RNA-seq dataset of a general flowering species, Shorea curtisii (Dipterocarpaceae), sequenced from leaves and buds collected at multiple vegetative and flowering phenological stages. We assembled 64,219 unigenes from the transcriptome of which 1,730 and 3,559 were differentially expressed in the leaf and the bud, respectively. Differentially expressed unigene clusters were found to be enriched with homologs of Arabidopsis thaliana genes associated with response to biotic and abiotic stresses, nutrient level, and hormonal treatments. When combined with rainfall data, our transcriptome data reveals that the trees were responding to a brief period of drought prior to the elevated expression of key floral promoters and followed by differential expression of unigenes that indicates physiological changes associated with the transition from vegetative to reproductive stages. Our study is timely for a representative general flowering dipterocarp species that occurs in forests that are under the constant threat of deforestation and climate change as it pinpoints important climate sensitive and flowering-related homologs and offers a glimpse into the cascade of gene expression before and after the onset of floral initiation.


Assuntos
Dipterocarpaceae , Transcriptoma , Animais , Transcriptoma/genética , Dipterocarpaceae/genética , Flores/genética , Perfilação da Expressão Gênica , Reprodução/genética
16.
Brain Commun ; 5(3): fcad182, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37361715

RESUMO

Reliable definitions, classifications and prognostic models are the cornerstones of stratified medicine, but none of the current classifications systems in epilepsy address prognostic or outcome issues. Although heterogeneity is widely acknowledged within epilepsy syndromes, the significance of variation in electroclinical features, comorbidities and treatment response, as they relate to diagnostic and prognostic purposes, has not been explored. In this paper, we aim to provide an evidence-based definition of juvenile myoclonic epilepsy showing that with a predefined and limited set of mandatory features, variation in juvenile myoclonic epilepsy phenotype can be exploited for prognostic purposes. Our study is based on clinical data collected by the Biology of Juvenile Myoclonic Epilepsy Consortium augmented by literature data. We review prognosis research on mortality and seizure remission, predictors of antiseizure medication resistance and selected adverse drug events to valproate, levetiracetam and lamotrigine. Based on our analysis, a simplified set of diagnostic criteria for juvenile myoclonic epilepsy includes the following: (i) myoclonic jerks as mandatory seizure type; (ii) a circadian timing for myoclonia not mandatory for the diagnosis of juvenile myoclonic epilepsy; (iii) age of onset ranging from 6 to 40 years; (iv) generalized EEG abnormalities; and (v) intelligence conforming to population distribution. We find sufficient evidence to propose a predictive model of antiseizure medication resistance that emphasises (i) absence seizures as the strongest stratifying factor with regard to antiseizure medication resistance or seizure freedom for both sexes and (ii) sex as a major stratifying factor, revealing elevated odds of antiseizure medication resistance that correlates to self-report of catamenial and stress-related factors including sleep deprivation. In women, there are reduced odds of antiseizure medication resistance associated with EEG-measured or self-reported photosensitivity. In conclusion, by applying a simplified set of criteria to define phenotypic variations of juvenile myoclonic epilepsy, our paper proposes an evidence-based definition and prognostic stratification of juvenile myoclonic epilepsy. Further studies in existing data sets of individual patient data would be helpful to replicate our findings, and prospective studies in inception cohorts will contribute to validate them in real-world practice for juvenile myoclonic epilepsy management.

17.
NPJ Genom Med ; 8(1): 28, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770509

RESUMO

Elevated impulsivity is a key component of attention-deficit hyperactivity disorder (ADHD), bipolar disorder and juvenile myoclonic epilepsy (JME). We performed a genome-wide association, colocalization, polygenic risk score, and pathway analysis of impulsivity in JME (n = 381). Results were followed up with functional characterisation using a drosophila model. We identified genome-wide associated SNPs at 8q13.3 (P = 7.5 × 10-9) and 10p11.21 (P = 3.6 × 10-8). The 8q13.3 locus colocalizes with SLCO5A1 expression quantitative trait loci in cerebral cortex (P = 9.5 × 10-3). SLCO5A1 codes for an organic anion transporter and upregulates synapse assembly/organisation genes. Pathway analysis demonstrates 12.7-fold enrichment for presynaptic membrane assembly genes (P = 0.0005) and 14.3-fold enrichment for presynaptic organisation genes (P = 0.0005) including NLGN1 and PTPRD. RNAi knockdown of Oatp30B, the Drosophila polypeptide with the highest homology to SLCO5A1, causes over-reactive startling behaviour (P = 8.7 × 10-3) and increased seizure-like events (P = 6.8 × 10-7). Polygenic risk score for ADHD genetically correlates with impulsivity scores in JME (P = 1.60 × 10-3). SLCO5A1 loss-of-function represents an impulsivity and seizure mechanism. Synaptic assembly genes may inform the aetiology of impulsivity in health and disease.

18.
Mol Carcinog ; 51 Suppl 1: E74-82, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22213098

RESUMO

Nasopharyngeal carcinoma (NPC) is a multifactorial and polygenic disease with high incidence in Asian countries. Epstein-Barr virus infection, environmental and genetic factors are believed to be involved in the tumorigenesis of NPC. The association of single nucleotide polymorphisms (SNPs) in LPLUNC1 and SPLUNC1 genes with NPC was investigated by performing a two-stage case control association study in a Malaysian Chinese population. The initial screening consisted of 81 NPC patients and 147 healthy controls while the replication study consisted of 366 NPC patients and 340 healthy controls. The combined analysis showed that a SNP (rs2752903) of SPLUNC1 was significantly associated with the risk of NPC (combined P = 0.00032, odds ratio = 1.62, 95% confidence interval = 1.25-2.11). In the subsequent dense fine mapping of SPLUNC1 locus, 36 SNPs in strong linkage disequilibrium with rs2752903 (r(2) ≥ 0.85) were associated with NPC susceptibility. Screening of these variants by electrophoretic mobility shift and luciferase reporter assays showed that rs1407019 located in intron 3 (r(2) = 0.994 with rs2752903) caused allelic difference in the binding of specificity protein 1 (Sp1) transcription factor and affected luciferase activity. This SNP may consequently alter the expression of SPLUNC1 in the epithelial cells. In summary, our study suggested that rs1407019 in intronic enhancer of SPLUNC1 is associated with NPC susceptibility in which its A allele confers an increased risk of NPC in the Malaysian Chinese population.


Assuntos
Glicoproteínas/genética , Neoplasias Nasofaríngeas/genética , Fosfoproteínas/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Autoantígenos , Carcinoma , Estudos de Casos e Controles , China/etnologia , Ensaio de Desvio de Mobilidade Eletroforética , Proteínas de Ligação a Ácido Graxo , Feminino , Predisposição Genética para Doença , Humanos , Íntrons , Desequilíbrio de Ligação , Malásia , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Razão de Chances , Proteínas/genética , Distribuição Aleatória , Adulto Jovem
19.
Genes Genomics ; 44(8): 957-966, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35689754

RESUMO

BACKGROUND: Current advances in the molecular biology of multiple myeloma (MM) are not sufficient to fully delineate the genesis and development of this disease. OBJECTIVE: This study aimed to identify molecular targets underlying MM pathogenesis. METHODS: mRNA expression profiling for 29 samples (19 MM samples, 7 MM cell lines and 3 controls) were obtained using microarray. We evaluated the in vitro effects of RAD54L gene silencing on the proliferation, apoptosis and cell cycle distribution in KMS-28BM human MM cells using siRNA approach. Cell proliferation was determined by MTS assay while apoptosis and cell cycle distribution were analysed with flow cytometry. Gene and protein expression was evaluated using RT-qPCR and ELISA, respectively. RESULTS: Microarray results revealed a total of 5124 differentially expressed genes (DEGs), in which 2696 and 2428 genes were up-regulated and down-regulated in MM compared to the normal controls, respectively (fold change ≥ 2.0; P < 0.05). Up-regulated genes (RAD54L, DIAPH3, SHCBP1, SKA3 and ANLN) and down-regulated genes (HKDC1, RASGRF2, CYSLTR2) have never been reported in association with MM. Up-regulation of RAD54L was further verified by RT-qPCR (P < 0.001). In vitro functional studies revealed that RAD54L gene silencing significantly induced growth inhibition, apoptosis (small changes) and cell cycle arrest in G0/G1 phase in KMS-28BM (P < 0.05). Silencing of RAD54L also decreased its protein level (P < 0.05). CONCLUSIONS: This study has identified possible molecular targets underlying the pathogenesis of MM. For the first time, we reveal RAD54L as a potential therapeutic target in MM, possibly functioning in the cell cycle and checkpoint control.


Assuntos
Mieloma Múltiplo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Perfilação da Expressão Gênica/métodos , Inativação Gênica , Humanos , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mieloma Múltiplo/genética , Mieloma Múltiplo/metabolismo , Proteínas Adaptadoras da Sinalização Shc/genética , Proteínas Adaptadoras da Sinalização Shc/metabolismo
20.
Biomed J ; 45(3): 542-548, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35660364

RESUMO

BACKGROUND: Periventricular nodular heterotopia (PVNH) is caused by abnormal neuronal migration, resulting in the neurons accumulate as nodules along the surface of the lateral ventricles. PVNH often cause epilepsy, psychomotor development or cognition problem. Mutations in FLNA (Filamin A) is the most common underlying genetic etiology. Our purpose is to delineate the clinical and imaging spectrum that differentiates FLNA-positive and FLNA-negative PVNH patients. METHODS: We included 21 patients with confirmed PVNH. The detailed clinical information, electroencephalography, and other clinical findings were recorded. Detailed brain MR imaging was assessed. Mutation analysis of the FLNA gene was used Sanger sequencing or a next generation sequencing based assay. RESULTS: FLNA mutations were identified in 9 patients (7 females and 2 males), including two nonsense, two splice site, three frameshift, and two missense mutations. In FLNA-positive group, 8 patients had anterior predominant bilateral symmetric presentation and only one had asymmetrical distribution and dilated ventricles. Extra-cerebral features were more often observed in FLNA-positive group than FLNA-negative group. CONCLUSION: Genetics of PVNH is heterogenous, and mutations in FLNA gene account for less than half of the patients in our cohort. Our finding between FLNA-positive and FLNA-negative patients could guide the clinicians to select relevant genetic testing.


Assuntos
Epilepsia , Heterotopia Nodular Periventricular , Encéfalo , Eletroencefalografia , Feminino , Filaminas/genética , Humanos , Imageamento por Ressonância Magnética , Masculino , Heterotopia Nodular Periventricular/diagnóstico por imagem , Heterotopia Nodular Periventricular/genética
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