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1.
Health Sci Rep ; 6(10): e1614, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37818312

RESUMO

Background and Aims: Noncommunicable diseases have emerged as a major cause of morbidity and mortality worldwide among which the majority of the deaths are caused by cardiovascular diseases. Estimating the risk of cardiovascular diseases helps eliminate the risk factors and prevent developing cardiovascular diseases in the future. The World Health Organization in association with the International Society of Hypertension has developed risk charts for the estimation of 10-year risk for cardiovascular diseases. This study aimed to estimate 10-year cardiovascular risk in the Nepalese population using nonlaboratory-based charts. Methods: A hospital-based cross-sectional study was conducted among 314 adults aged 40-74 years visiting the outpatient departments of Shishuwa Hospital in western Nepal. Systematic random sampling was used to select the participants. Questionnaire-guided short interviews, physical examination, and anthropometric measurements were done. The χ 2 test was used to test the significance and a p < 0.05 was considered statistically significant. Results: As per the risk estimation charts, high cardiovascular risk (20%-30%) was seen in 6.1% of total participants and moderate cardiovascular risk (10%-20%) was found in 29% of participants. The moderate-high risk was significantly higher among male participants compared to females (p < 0.01). Of all the participants, 22.0% were current smokers, 17.2% were alcohol users, 61.1% were hypertensive, and 35.7% were diabetics. Smoking tobacco, alcohol use, and hypertension were significantly more prevalent among the male participants. (p < 0.01) Adults in the 50-59 years age group had a significantly high prevalence of hypertension (p < 0.01), diabetes (p = 0.02), and alcohol abuse (p = 0.01). Conclusion: This study shows high cardiovascular risk among adult population in western Nepal. The 10-year cardiovascular risk score and risk factors were significantly higher among males than females. There seems to be a prompt necessity of health promotion interventions to reduce cardiovascular risk factors and prevent the burden of cardiovascular diseases in Nepal.

2.
Brain ; 146(4): 1342-1356, 2023 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-36226386

RESUMO

Understanding the exact molecular mechanisms involved in the aetiology of epileptogenic pathologies with or without tumour activity is essential for improving treatment of drug-resistant focal epilepsy. Here, we characterize the landscape of somatic genetic variants in resected brain specimens from 474 individuals with drug-resistant focal epilepsy using deep whole-exome sequencing (>350×) and whole-genome genotyping. Across the exome, we observe a greater number of somatic single-nucleotide variants in low-grade epilepsy-associated tumours (7.92 ± 5.65 single-nucleotide variants) than in brain tissue from malformations of cortical development (6.11 ± 4 single-nucleotide variants) or hippocampal sclerosis (5.1 ± 3.04 single-nucleotide variants). Tumour tissues also had the largest number of likely pathogenic variant carrying cells. low-grade epilepsy-associated tumours had the highest proportion of samples with one or more somatic copy-number variants (24.7%), followed by malformations of cortical development (5.4%) and hippocampal sclerosis (4.1%). Recurring somatic whole chromosome duplications affecting Chromosome 7 (16.8%), chromosome 5 (10.9%), and chromosome 20 (9.9%) were observed among low-grade epilepsy-associated tumours. For germline variant-associated malformations of cortical development genes such as TSC2, DEPDC5 and PTEN, germline single-nucleotide variants were frequently identified within large loss of heterozygosity regions, supporting the recently proposed 'second hit' disease mechanism in these genes. We detect somatic variants in 12 established lesional epilepsy genes and demonstrate exome-wide statistical support for three of these in the aetiology of low-grade epilepsy-associated tumours (e.g. BRAF) and malformations of cortical development (e.g. SLC35A2 and MTOR). We also identify novel significant associations for PTPN11 with low-grade epilepsy-associated tumours and NRAS Q61 mutated protein with a complex malformation of cortical development characterized by polymicrogyria and nodular heterotopia. The variants identified in NRAS are known from cancer studies to lead to hyperactivation of NRAS, which can be targeted pharmacologically. We identify large recurrent 1q21-q44 duplication including AKT3 in association with focal cortical dysplasia type 2a with hyaline astrocytic inclusions, another rare and possibly under-recognized brain lesion. The clinical-genetic analyses showed that the numbers of somatic single-nucleotide variant across the exome and the fraction of affected cells were positively correlated with the age at seizure onset and surgery in individuals with low-grade epilepsy-associated tumours. In summary, our comprehensive genetic screen sheds light on the genome-scale landscape of genetic variants in epileptic brain lesions, informs the design of gene panels for clinical diagnostic screening and guides future directions for clinical implementation of epilepsy surgery genetics.


Assuntos
Epilepsia Resistente a Medicamentos , Epilepsias Parciais , Epilepsia , Malformações do Desenvolvimento Cortical , Humanos , Epilepsia/patologia , Encéfalo/patologia , Epilepsia Resistente a Medicamentos/genética , Epilepsia Resistente a Medicamentos/cirurgia , Epilepsia Resistente a Medicamentos/metabolismo , Genômica , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/genética , Malformações do Desenvolvimento Cortical/metabolismo , Epilepsias Parciais/metabolismo , Nucleotídeos/metabolismo
3.
Clin Proteomics ; 19(1): 18, 2022 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-35610567

RESUMO

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is a common digestive tract malignant tumor with high incidence and dismal prognosis worldwide. However, the reliable biomarkers for clinical diagnosis and the underlying signaling pathways insights of ESCC are not unequivocally understood yet. The serum proteome may provide valuable clues for the early diagnosis of ESCC and the discovery of novel molecular insights. METHODS: In the current study, an optimized proteomics approach was employed to discover novel serum-based biomarkers for ESCC, and unveil abnormal signal pathways. Gene ontology (GO) enrichment analysis was done by Gene Set Enrichment Analysis (GSEA) and Metascape database, respectively. Pathway analysis was accomplished by GeneCards database. The correlation coefficient was assessed using Pearson and distance correlation analyses. Prioritized candidates were further verified in two independent validation sets by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) staining. RESULTS: A total of 633 non-redundant proteins were identified in the serum of patients with ESCC, of which 59 and 10 proteins displayed a more than 1.5-fold increase or decrease compared with healthy controls. Verification was performed for six candidate biomarkers, including S100A8/A9, SAA1, ENO1, TPI1 and PGAM1. Receiver operating characteristics (ROC) curve plotting showed the high diagnostic sensitivity and specificity of these six protein molecules as a biomarker panel: the area under characteristic curve (AUC) is up to 0.945. Differentially expressed proteins were subjected to functional enrichment analysis, which revealed the dysregulation of signaling pathways mainly involved in glycolysis, TLR4, HIF-1α, Cori cycle, TCA cycle, folate metabolism, and platelet degranulation. The latter finding was all the more noteworthy as a strong positive correlation was discovered between activated glycolysis and TLR4 pathways and unfavorable clinicopathological TNM stages in ESCC. CONCLUSIONS: Our findings propose a potential serum biomarker panel for the early detection and diagnosis of ESCC, which could potentially broaden insights into the characteristics of ESCC from the proteomic perspective.

4.
Viruses ; 13(7)2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34372582

RESUMO

Ebolavirus (EBOV) is a negative-sense RNA virus that causes severe hemorrhagic fever in humans. The matrix protein VP40 facilitates viral budding by binding to lipids in the host cell plasma membrane and driving the formation of filamentous, pleomorphic virus particles. The C-terminal domain of VP40 contains two highly-conserved cysteine residues at positions 311 and 314, but their role in the viral life cycle is unknown. We therefore investigated the properties of VP40 mutants in which the conserved cysteine residues were replaced with alanine. The C311A mutation significantly increased the affinity of VP40 for membranes containing phosphatidylserine (PS), resulting in the assembly of longer virus-like particles (VLPs) compared to wild-type VP40. The C314A mutation also increased the affinity of VP40 for membranes containing PS, albeit to a lesser degree than C311A. The double mutant behaved in a similar manner to the individual mutants. Computer modeling revealed that both cysteine residues restrain a loop segment containing lysine residues that interact with the plasma membrane, but Cys311 has the dominant role. Accordingly, the C311A mutation increases the flexibility of this membrane-binding loop, changes the profile of hydrogen bonding within VP40 and therefore binds to PS with greater affinity. This is the first evidence that mutations in VP40 can increase its affinity for biological membranes and modify the length of Ebola VLPs. The Cys311 and Cys314 residues therefore play an important role in dynamic interactions at the plasma membrane by modulating the ability of VP40 to bind PS.


Assuntos
Ebolavirus/genética , Proteínas da Matriz Viral/genética , Animais , Células COS , Membrana Celular/metabolismo , Chlorocebus aethiops , Cisteína/genética , Ebolavirus/metabolismo , Humanos , Lipídeos/fisiologia , Simulação de Dinâmica Molecular , Fosfatidilserinas/metabolismo , Polimorfismo de Nucleotídeo Único/genética , Ligação Proteica , Multimerização Proteica , Proteínas da Matriz Viral/metabolismo , Proteínas da Matriz Viral/ultraestrutura , Vírion/metabolismo , Montagem de Vírus/genética , Liberação de Vírus/genética
5.
J Phys Chem B ; 123(43): 9045-9053, 2019 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-31576755

RESUMO

The Ebola virus (EBOV) is a virulent pathogen that causes severe hemorrhagic fever with a high fatality rate in humans. The EBOV transformer protein VP40 plays crucial roles in viral assembly and budding at the plasma membrane of infected cells. One of VP40's roles is to form the long, flexible, pleomorphic filamentous structural matrix for the virus. Each filament contains three unique interfaces: monomer NTD-NTD to form a dimer, dimer-to-dimer NTD-NTD oligomerization to form a hexamer, and end-to-end hexamer CTD-CTD to build the filament. However, the atomic-level details of conformational flexibility of the VP40 filament are still elusive. In this study, we have performed explicit-solvent, all-atom molecular dynamic simulations to explore the conformational flexibility of the three different interface structures of the filament. Using dynamic network analysis and other calculational methods, we find that the CTD-CTD hexamer interface with weak interdomain amino acid communities is the most flexible, and the NTD-NTD oligomer interface with strong interdomain communities is the least flexible. Our study suggests that the high flexibility of the CTD-CTD interface may be essential for the supple bending of the Ebola filovirus, and such flexibility may present a target for molecular interventions to disrupt the Ebola virus functioning.


Assuntos
Membrana Celular/metabolismo , Nucleoproteínas/química , Nucleoproteínas/metabolismo , Multimerização Proteica , Proteínas do Core Viral/química , Proteínas do Core Viral/metabolismo , Humanos , Simulação de Dinâmica Molecular , Conformação Proteica , Domínios e Motivos de Interação entre Proteínas
6.
Phys Chem Chem Phys ; 21(23): 12530-12539, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31147666

RESUMO

The emergence of antibiotic-resistance is a major concern to global human health and identification of novel antibiotics is critical to mitigate the threat. Mutacin 1140 (MU1140) is a promising antimicrobial lanthipeptide and is effective against Gram-positive bacteria. Like nisin, MU1140 targets and sequesters lipid II and interferes with its function, which results in the inhibition of bacterial cell wall synthesis, and leads to bacteria cell lysis. MU1140 contains a structurally similar thioether cage for binding the lipid II pyrophosphate as for nisin. In addition to lipid II binding, nisin is known to form membrane pores. Membrane pore formation and membrane disruption is a common mode of action for many antimicrobial peptides, including gallidermin, a lantibiotic peptide with similar structural features as MU1140. However, whether and how MU1140 and its variants can form permeable membrane pores remains to be demonstrated. In this work, we explored the potential mechanisms of membrane pore formation by performing molecular simulations of the MU1140-lipid II complex in the bacterial membrane. Our results suggest that MU1140-lipid II complexes are able to form water permeating membrane pores. We find that a single chain of MU1140 complexed with lipid II in the transmembrane region can permeate water molecules across the membrane via a single-file water transport mechanism. The ordering of the water molecules in the single-file chain region as well as the diffusion behavior is similar to those observed in other biological water channels. Multiple complexes of MU1140-lipid II in the membrane showed enhanced permeability for the water molecules, as well as a noticeable membrane distortion and lipid relocation, suggesting that a higher concentration of MU1140 assembly in the membrane can cause significant disruption of the bacterial membrane. These investigations provide an atomistic level insight into a novel mode of action for MU1140 that can be exploited to develop optimized peptide variants with improved antimicrobial properties.


Assuntos
Bacteriocinas/farmacologia , Bactérias Gram-Positivas/efeitos dos fármacos , Simulação de Dinâmica Molecular , Peptídeos/farmacologia , Bacteriocinas/química , Membrana Celular/efeitos dos fármacos , Bactérias Gram-Positivas/citologia , Lipídeos/química , Lipídeos/farmacologia , Testes de Sensibilidade Microbiana , Peptídeos/química , Água/química
7.
Shock ; 49(4): 466-473, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28682939

RESUMO

BACKGROUND: A complete understanding of the role of the liver in burn-induced hypermetabolism is lacking. We investigated the acute effect of severe burn trauma on liver mitochondrial respiratory capacity and coupling control as well as the signaling events underlying these alterations. METHODS: Male BALB/c mice (8-12 weeks) received full-thickness scald burns on ∼30% of the body surface. Liver tissue was harvested 24 h postinjury. Mitochondrial respiration was determined by high-resolution respirometry. Citrate synthase activity was determined as a proxy of mitochondrial density. Male Sprague-Dawley rats received full-thickness scald burns to ∼60% of the body surface. Serum was collected 24 h postinjury. HepG2 cells were cultured with serum-enriched media from either sham- or burn-treated rats. Protein levels were analyzed via western blot. RESULTS: Mass-specific (P = 0.01) and mitochondrial-specific (P = 0.01) respiration coupled to ATP production significantly increased in the liver after burn. The respiratory control ratio for ADP (P = 0.04) and the mitochondrial flux control ratio (P = 0.03) were elevated in the liver of burned animals. Complex III and Complex IV protein abundance in the liver increased after burn by 17% and 14%, respectively. Exposure of HepG2 cells to serum from burned rats increased the pAMPKα:AMPKα ratio (P < 0.001) and levels of SIRT1 (P = 0.01), Nrf2 (P < 0.001), and PGC1α (P = 0.02). CONCLUSIONS: Severe burn trauma augments respiratory capacity and function of liver mitochondria, adaptations that augment ATP production. This response may be mediated by systemic factors that activate signaling proteins responsible for regulating cellular energy metabolism and mitochondrial biogenesis.


Assuntos
Queimaduras/metabolismo , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias/metabolismo , Animais , Citrato (si)-Sintase/metabolismo , Transporte de Elétrons/fisiologia , Células Hep G2 , Hepatócitos/metabolismo , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ratos , Ratos Sprague-Dawley
8.
Biochem Biophys Res Commun ; 493(1): 176-181, 2017 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-28917841

RESUMO

Ebola virus infections cause hemorrhagic fever that often results in very high fatality rates. In addition to exploring vaccines, development of drugs is also essential for treating the disease and preventing the spread of the infection. The Ebola virus matrix protein VP40 exists in various conformational and oligomeric forms and is a potential pharmacological target for disrupting the virus life-cycle. Here we explored graphene-VP40 interactions using molecular dynamics simulations and graphene pelleting assays. We found that graphene sheets associate strongly with VP40 at various interfaces. We also found that the graphene is able to disrupt the C-terminal domain (CTD-CTD) interface of VP40 hexamers. This VP40 hexamer-hexamer interface is crucial in forming the Ebola viral matrix and disruption of this interface may provide a method to use graphene or similar nanoparticle based solutions as a disinfectant that can significantly reduce the spread of the disease and prevent an Ebola epidemic.


Assuntos
Grafite/química , Nucleoproteínas/química , Nucleoproteínas/ultraestrutura , Proteínas do Core Viral/química , Proteínas do Core Viral/ultraestrutura , Proteínas da Matriz Viral/química , Proteínas da Matriz Viral/ultraestrutura , Sítios de Ligação , Simulação de Dinâmica Molecular , Ligação Proteica , Conformação Proteica , Multimerização Proteica
9.
J Burn Care Res ; 37(1): 53-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26361327

RESUMO

The long-term impact of burn trauma on skeletal muscle bioenergetics remains unknown. Here, the authors determined respiratory capacity and function of skeletal muscle mitochondria in healthy individuals and in burn victims for up to 2 years postinjury. Biopsies were collected from the m. vastus lateralis of 16 healthy men (26 ± 4 years) and 69 children (8 ± 5 years) with burns encompassing ≥30% of their total BSA. Seventy-nine biopsies were collected from cohorts of burn victims at 2 weeks (n = 18), 6 months (n = 18), 12 months (n = 25), and 24 months (n = 18) postburn. Hypermetabolism was determined by the difference in predicted and measured metabolic rate. Mitochondrial respiration was determined in saponin-permeabilized myofiber bundles. Outcomes were modeled by analysis of variance, with differences in groups assessed by Tukey-adjusted contrasts. Burn patients were hypermetabolic for up to 2 years postinjury. Coupled mitochondrial respiration was lower at 2 weeks (17 [8] pmol/sec/mg; P < .001), 6 months (41 [30] pmol/sec/mg; P = .03), and 12 months (35 [14] pmol/sec/mg; P < .001) postburn compared with healthy controls (58 [13] pmol/sec/mg). Coupled respiration was greater at 6, 12, and 24 months postburn vs 2 weeks postburn (P < .001). Mitochondrial adenosine diphosphate and oligomycin sensitivity (measures of coupling control) were lower at all time-points postburn vs control (P < .05), but greater at 6, 12, and 24 months postburn vs 2 weeks postburn (P < .05). Muscle mitochondrial respiratory capacity remains significantly lower in burn victims for 1-year postinjury. Mitochondrial coupling control is diminished for up to 2 years postinjury in burn victims, resulting in greater mitochondrial thermogenesis. These quantitative and qualitative derangements in skeletal muscle bioenergetics likely contribute to the long-term pathophysiological stress response to burn trauma.


Assuntos
Queimaduras/metabolismo , Queimaduras/fisiopatologia , Metabolismo Energético/fisiologia , Mitocôndrias Musculares/fisiologia , Músculo Esquelético/metabolismo , Músculo Esquelético/fisiopatologia , Adolescente , Adulto , Queimaduras/complicações , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
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