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1.
J Med Virol ; 96(4): e29607, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628076

RESUMO

Hepatitis B e antigen (HBeAg) seropositivity during the natural history of chronic hepatitis B (CHB) is known to coincide with significant increases in serum and intrahepatic HBV DNA levels. However, the precise underlying mechanism remains unclear. In this study, we found that PreC (HBeAg precursor) genetic ablation leads to reduced viral replication both in vitro and in vivo. Furthermore, PreC impedes the proteasomal degradation of HBV polymerase, promoting viral replication. We discovered that PreC interacts with SUV39H1, a histone methyltransferase, resulting in a reduction in the expression of Cdt2, an adaptor protein of CRL4 E3 ligase targeting HBV polymerase. SUV39H1 induces H3K9 trimethylation of the Cdt2 promoter in a PreC-induced manner. CRISPR-mediated knockout of endogenous SUV39H1 or pharmaceutical inhibition of SUV39H1 decreases HBV loads in the mouse liver. Additionally, genetic depletion of Cdt2 in the mouse liver abrogates PreC-related HBV replication. Interestingly, a negative correlation of intrahepatic Cdt2 with serum HBeAg and HBV DNA load was observed in CHB patient samples. Our study thus sheds light on the mechanistic role of PreC in inducing HBV replication and identifies potential therapeutic targets for HBV treatment.


Assuntos
Vírus da Hepatite B , Hepatite B Crônica , Animais , Humanos , Camundongos , DNA Viral , Antígenos E da Hepatite B , Vírus da Hepatite B/genética , Metiltransferases , Proteínas Repressoras/genética , Replicação Viral
2.
Virus Genes ; 56(2): 109-119, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32026198

RESUMO

The nomenclature of the hepatitis B virus (HBV) genes and their products has developed stepwise, occasionally in an erratic way, creating many misunderstandings, especially among those who do not know the structure of HBV and its genome in detail. One of the most frequent misunderstandings, even presented in leading journals, is the designation of HBV "e"-antigen as envelope or early antigen. Another problem area are the so-called "pre" regions in the HBV genome present upstream of both the core and the surface genes of HBV, inadvertently suggesting that they may be a part of corresponding precursor proteins. Misnomers and misclassifications are frequent in defining the subgenotypes and serological subtypes of HBV. Even the well-established terminology for HBV surface (HBs) or HBV core (HBc) antigen deviates from the conventional virological nomenclature for viral envelopes or capsid proteins/antigens, respectively. Another matter of undesirable variability between publications is the numbering of the nucleotides and the graphical representation of genomic maps. This editorial briefly explains how the nomenclature evolved, what it really means, and suggests how it could be adapted to today's knowledge.


Assuntos
Anticorpos Anti-Hepatite B/imunologia , Antígenos E da Hepatite B/imunologia , Vírus da Hepatite B/imunologia , Hepatite B/imunologia , Epitopos/genética , Epitopos/imunologia , Variação Genética/genética , Variação Genética/imunologia , Hepatite B/genética , Hepatite B/virologia , Anticorpos Anti-Hepatite B/classificação , Antígenos do Núcleo do Vírus da Hepatite B/classificação , Antígenos do Núcleo do Vírus da Hepatite B/imunologia , Antígenos de Superfície da Hepatite B/classificação , Antígenos de Superfície da Hepatite B/imunologia , Antígenos E da Hepatite B/classificação , Vírus da Hepatite B/patogenicidade , Humanos , Terminologia como Assunto
3.
Zhongguo Zhong Yao Za Zhi ; 43(2): 345-352, 2018 Jan.
Artigo em Zh | MEDLINE | ID: mdl-29552854

RESUMO

Flavonoids are the most abundant constituents and induce these the rapeutic effects against inflammation, gastrointestinal infections, cardiovascular diseases, and respiratory. Most of these flavonoids have low content in Scutellarie Radix. It was difficult to detect some minor compounds by using LC-MS method with full scan. Based on the review of flavonoids that had been extracted from Scutellariae Radix, a method with PREC-IDA-EPI technique was developed and applied to Scutellariae Radix by using UPLC-MS/MS. A total of 97 flavonoids were identified, including 29 aglycones and 68 O-glycosides. This study laid the foundation for pharmacodynamicss of Scutellariae Radix.It is believed that an individual detection scheme based on the PREC-IDA-EPI technique could be used to identify unknown compounds.


Assuntos
Medicamentos de Ervas Chinesas/química , Flavonoides/isolamento & purificação , Scutellaria baicalensis/química , Cromatografia Líquida , Espectrometria de Massas em Tandem
4.
Biochim Biophys Acta ; 1845(1): 1-19, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24269900

RESUMO

N-myc down-regulated gene 1 (NDRG1) is a known metastasis suppressor in multiple cancers, being also involved in embryogenesis and development, cell growth and differentiation, lipid biosynthesis and myelination, stress responses and immunity. In addition to its primary role as a metastasis suppressor, NDRG1 can also influence other stages of carcinogenesis, namely angiogenesis and primary tumour growth. NDRG1 is regulated by multiple effectors in normal and neoplastic cells, including N-myc, histone acetylation, hypoxia, cellular iron levels and intracellular calcium. Further, studies have found that NDRG1 is up-regulated in neoplastic cells after treatment with novel iron chelators, which are a promising therapy for effective cancer management. Although the pathways by which NDRG1 exerts its functions in cancers have been documented, the relationship between the molecular structure of this protein and its functions remains unclear. In fact, recent studies suggest that, in certain cancers, NDRG1 is post-translationally modified, possibly by the activity of endogenous trypsins, leading to a subsequent alteration in its metastasis suppressor activity. This review describes the role of this important metastasis suppressor and discusses interesting unresolved issues regarding this protein.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neoplasias/terapia , Proteínas Supressoras de Tumor/fisiologia , Sequência de Aminoácidos , Animais , Proteínas de Ciclo Celular/análise , Proteínas de Ciclo Celular/química , Diferenciação Celular , Desenvolvimento Embrionário , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/análise , Peptídeos e Proteínas de Sinalização Intracelular/química , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Tripsina/fisiologia
5.
Viruses ; 16(6)2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38932231

RESUMO

Porcine hemagglutinating encephalomyelitis virus (PHEV) replicates in the upper respiratory tract and tonsils of pigs. Using an air-liquid interface porcine respiratory epithelial cells (ALI-PRECs) culture system, we demonstrated that PHEV disrupts respiratory epithelia homeostasis by impairing ciliary function and inducing antiviral, pro-inflammatory cytokine, and chemokine responses. This study explores the mechanisms driving early innate immune responses during PHEV infection through host transcriptome analysis. Total RNA was collected from ALI-PRECs at 24, 36, and 48 h post inoculation (hpi). RNA-seq analysis was performed using an Illumina Hiseq 600 to generate 100 bp paired-end reads. Differential gene expression was analyzed using DeSeq2. PHEV replicated actively in ALI-PRECs, causing cytopathic changes and progressive mucociliary disruption. Transcriptome analysis revealed downregulation of cilia-associated genes such as CILK1, DNAH11, LRRC-23, -49, and -51, and acidic sialomucin CD164L2. PHEV also activated antiviral signaling pathways, significantly increasing the expression of interferon-stimulated genes (RSAD2, MX1, IFIT, and ISG15) and chemokine genes (CCL5 and CXCL10), highlighting inflammatory regulation. This study contributes to elucidating the molecular mechanisms of the innate immune response to PHEV infection of the airway epithelium, emphasizing the critical roles of the mucociliary, interferon, and chemokine responses.


Assuntos
Betacoronavirus 1 , Células Epiteliais , Perfilação da Expressão Gênica , Interferons , Animais , Suínos , Células Epiteliais/virologia , Células Epiteliais/imunologia , Interferons/genética , Interferons/metabolismo , Interferons/imunologia , Betacoronavirus 1/imunologia , Betacoronavirus 1/genética , Imunidade Inata , Replicação Viral , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/virologia , Infecções por Coronavirus/veterinária , Citocinas/metabolismo , Citocinas/genética , Citocinas/imunologia , Transcriptoma , Mucosa Respiratória/virologia , Mucosa Respiratória/imunologia , Doenças dos Suínos/virologia , Doenças dos Suínos/imunologia , Doenças dos Suínos/genética , Células Cultivadas , Deltacoronavirus
6.
Neuroimage ; 83: 937-50, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23872496

RESUMO

Functional connectivity (FC) as measured by correlation between fMRI BOLD time courses of distinct brain regions has revealed meaningful organization of spontaneous fluctuations in the resting brain. However, an increasing amount of evidence points to non-stationarity of FC; i.e., FC dynamically changes over time reflecting additional and rich information about brain organization, but representing new challenges for analysis and interpretation. Here, we propose a data-driven approach based on principal component analysis (PCA) to reveal hidden patterns of coherent FC dynamics across multiple subjects. We demonstrate the feasibility and relevance of this new approach by examining the differences in dynamic FC between 13 healthy control subjects and 15 minimally disabled relapse-remitting multiple sclerosis patients. We estimated whole-brain dynamic FC of regionally-averaged BOLD activity using sliding time windows. We then used PCA to identify FC patterns, termed "eigenconnectivities", that reflect meaningful patterns in FC fluctuations. We then assessed the contributions of these patterns to the dynamic FC at any given time point and identified a network of connections centered on the default-mode network with altered contribution in patients. Our results complement traditional stationary analyses, and reveal novel insights into brain connectivity dynamics and their modulation in a neurodegenerative disease.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Esclerose Múltipla Recidivante-Remitente/fisiopatologia , Vias Neurais/fisiologia , Análise de Componente Principal , Descanso/fisiologia , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino
7.
J Neuroradiol ; 40(4): 267-80, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23433722

RESUMO

We investigated the cerebral networks involved in execution and mental imagery of sequential movements of the left foot, both performed at slow and fast speed. Twelve volunteers were scanned with a 3T MRI during execution and imagination of a sequence of ankle movements. Overt movement execution and motor imagery shared a common network including the premotor, parietal and cingulate cortices, the striatum and the cerebellum. Motor imagery recruited specifically the prefrontal cortex, whereas motor execution recruited specifically the sensorimotor cortex. We also found that slow movements specifically recruited frontopolar and right dorsomedian prefrontal areas bilaterally, during both execution and mental imagery, whereas fast movements strongly activated the sensorimotor cerebral cortex. Finally, we noted that anterior vermis, lobules VI/VII and VIII of the cerebellum were specifically activated during fast movements, both in imagination and execution. We show that the selection of the neural networks underlying voluntary movement of the foot is depending on the speed strategy and is sensitive to execution versus imagery. Moreover, to the light of surprising recent findings in monkeys showing that the vermis should no longer be considered as entirely isolated from the cerebral cortex (Coffman et al., 2011 [2]), we suggest that the anterior vermis contributes to computational aspects of fast commands, whereas more lateral cerebellar superior lobe and lobule VIII would regulate patterning and sequencing of submovements in conjunction with movement rate. We also suggest that execution of overt slow movements, which strongly involves prefrontal executive cortex as during motor mental imagery, is associated with conscious mental representation of the ongoing movements.


Assuntos
Articulação do Tornozelo/fisiologia , Encéfalo/fisiologia , Imaginação/fisiologia , Movimento/fisiologia , Rede Nervosa/fisiologia , Esforço Físico/fisiologia , Desempenho Psicomotor/fisiologia , Adulto , Mapeamento Encefálico/métodos , Potencial Evocado Motor/fisiologia , Retroalimentação Fisiológica/fisiologia , Feminino , Humanos , Masculino
8.
Chemosphere ; 334: 138953, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37196788

RESUMO

Widespread distributions of short-chain perfluoroalkyl substances (PFASs) has been recognized as a crucial environmental issue. However, multiple treatment techniques were ineffective due to their high polarity and mobility, contributing to a never-ending existence in the aquatic environment ubiquitously. The present study revealed potential technique of periodically reversing electrocoagulation (PREC) to perform efficient removal of short-chain PFASs including experimental factors (in the conditions of 9 V for voltage, 600 r/min of stirring speed, 10 s of reversing period, and 2 g/L of NaCl electrolyte), orthogonal experiments, actual application, and removal mechanism. Accordingly, based upon the orthogonal experiments, the removal efficiencies of perfluorobutane sulfonate (PFBS) in simulated solution could achieve 81.0% with the optimal parameters of Fe-Fe electrode materials, addition of 665 µL H2O2 per 10 min, and pH at 3.0. The PREC was further applied for treating the actual groundwater around a fluorochemical facility, consequently the removal efficiencies for typical short-chain perfluorobutanoic acid (PFBA), perfluoropentanoic acid (PFPeA), perfluorohexanoic acid (PFHxA), PFBS, and perfluoropentane sulfonate (PFPeS) were 62.5%, 89.0%, 96.4%, 90.0%, and 97.5%, respectively. The other long-chain PFASs contaminants had superior removal with the removal efficiencies up to 97%-100%. In addition, a comprehensive removal mechanism related to electric attraction adsorption for short-chain PFASs could be verified through the morphological analysis of ultimate flocs composition. The oxidation degradation was further revealed as the other removal mechanism by suspect and nontarget screening of intermediates formed in simulated solution, as well as density functional theory (DFT) calculation theory. Moreover, the degradation pathways about one CF2O molecule or CO2 eliminated with one C atom removed in PFBS by ·OH generated from the PREC oxidation process were further proposed. As a result, the PREC would be a promising technique for the efficient removal of short-chain PFASs from severely contaminated water bodies.


Assuntos
Fluorocarbonos , Água Subterrânea , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Peróxido de Hidrogênio/análise , Água Subterrânea/química , Eletrocoagulação , Fluorocarbonos/análise
9.
Chemosphere ; 307(Pt 2): 135874, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35926750

RESUMO

Increasing attentions have been paid on widespread contaminations of perfluoroalkyl substances (PFAS). Particularly, simultaneous occurrence of multiple PFAS in the aquatic environments globally has been recognized as a crucial emerging issue. The present study aimed to perform simultaneous removal of multiple PFAS contaminations from groundwater around a fluorochemical facility based upon the technique of periodically reversing electrocoagulation (PREC). Accordingly, the experiments were implemented on the best conditions, actual application, and removal mechanism in the process of PREC with Al-Zn electrodes. Consequently, 1 mg/L synthetic solution of ten PFAS could be eliminated ideally during the initial 10 min, under the optimal conditions involving voltage at 12 V, pH at 7.0, and electrolyte with NaCl. The maximum removal rates of perfluorobutanoic acid (PFBA), perfluorobutane sulfonate (PFBS), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonate (PFOS) were 90.9%, 91.0%, 99.7%, and 100%, respectively. The PREC performed a significant improvement for the wide scope of PFAS removal with the levels ranging from 10 µg/L to 100 mg/L. In addition, the optimized PREC technique was further applied to remove various PFAS contaminations from the natural groundwater samples underneath the fluorochemical facility, subsequently generating the removal efficiencies in the range between 31.3% and 99.9%, showing the observable advantages compared with other removal techniques for the actual application. Finally, the mechanism of PFAS removal was mainly related to enmeshment and synergistic bridging adsorption, together with oxidation degradation that determined by potential formation of short-chain PFAS in the PREC process. As a result, the PREC technique would be a promising technique for the efficient removal of multiple PFAS contaminations simultaneously from natural water bodies.


Assuntos
Ácidos Alcanossulfônicos , Fluorocarbonos , Água Subterrânea , Poluentes Químicos da Água , Eletrocoagulação , Fluorocarbonos/análise , Água Subterrânea/química , Cloreto de Sódio , Água , Poluentes Químicos da Água/análise
10.
Front Microbiol ; 13: 865124, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35359734

RESUMO

Up to now, it has not been clear whether occult hepatitis B virus (HBV) infection (OBI) can be treated with antiviral therapy whether OBI can develop drug resistance gene mutation or not. We report a middle-aged female patient with OBI who showed HBV reactivation (HBVr) during more than 3 years of intermittent entecavir (ETV) antiviral therapy: seropositive HBV surface antigen (HBsAg), increased e antigen (HBeAg), and repeatedly elevated serum HBV DNA. Genotype analysis showed that the patient was infected with HBV type B. Genetic sequencing of HBV showed the mutants of S143T, D144G, and G145R in the S gene region, and the mutant of site 1896 in the pre-Core region coexisted with the wild type (G1896A/G). No mutation was found in other HBV gene segments. Drug resistance gene analysis found RtL229W mutant, resistant to lamivudine but sensitive to ETV and other nucleoside analogs. This case of OBI provides us with the following clinical experiences: Firstly, it is necessary to detect HBV genotype, mutation, and drug-resistant genes at the initial diagnosis, which can be helpful for reasonable treatment. Secondly, identifying the risk factors and mechanisms associated with HBVr could help quantify the risk of HBVr and manage the clinical consequences. Thirdly, the OBI patients with hepatitis B e antigen-positive, HBV DNA > 1 × 103 IU/ml should be recommended regular and continuous antiviral therapy as soon as possible to prevent the occurrence of hepatocirrhosis and hepatocellular carcinoma (HCC).

11.
One Health ; 15: 100449, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36532675

RESUMO

Brucellosis is a typical zoonosis driven by various risk factors, including environmental ones. The present study aimed to explore the driving effect of environmental factors on human brucellosis in a high incidence rate area, which provides understanding and implications in mitigating disease transmission risk in a multi-system between the human-animal-environment interface for preventing and controlling brucellosis based on the One Health concept. Based on the monthly time series data of human brucellosis and environmental variables, a Seasonal Autoregressive Integrated Moving Average Model with explanatory variables (SARIMAX) was applied to assess the association between environmental indicators and human brucellosis incidence (IHB). The results indicated distinct seasonal fluctuation during the study duration, tending to climb from April to August. Atmospheric pressure, precipitation, relative humidity, mean temperature, sunshine duration, and normalized difference vegetation index significantly drive IHB. Moreover, the well-fitting and predicting capability were performed and assessed in the optimal model was the SARIMAX (0,1,1) (0,1,1)12 model with the normalized difference vegetation index (ß = 0.349, P = 0.036) and mean temperature (ß = 0.133, P = 0.046) lagged in 6 months, and the precipitation lagged in 1 month (ß = -0.090, P = 0.004). Our study suggests the association between environmental risk factors and human brucellosis infection, which can be contributed to mitigating the transmission risk in the environmental drivers in a multi-system interface through comprehensive prevention and intervention strategies based on the One Health concept.

12.
Chemosphere ; 248: 125951, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32000036

RESUMO

Severe contaminations of perfluoroalkanesulfonic acids (PFSAs) existed in the natural groundwater beneath a fluorochemical industrial park (FIP) in Fuxin of China. In the present study, systematic researches were performed to determine the best conditions of efficient treatment for 1 mg L-1 of PFSAs in the synthetic groundwater samples with the periodically reverse electrocoagulation (PREC) using the Al-Zn electrodes. Based upon the orthogonal experiments, the removal efficiencies of perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), and perfluorooctane sulfonate (PFOS) could reach 87.4%, 95.6%, and 100%, respectively, within the initial 10 min, under the optimal conditions of voltage at 12.0 V, pH at 7.0, and stirring speed at 400 rpm. In addition, the optimized PREC technique was further applied to remove the PFSA contaminations from the natural groundwater samples of the Fuxin FIP, subsequently generating the removal efficiencies of three target PFSA analytes in the range between 59.0% and 100% at 60 min. Moreover, the SEM-EDS analyses showed the hydroxide flocs formed during the process of PREC treatment had clear characteristics of floc aggregates, with the major constituents of O, Al, C, N, Zn, and F elements. As a result, long-chain PFHxS and PFOS tended to be eliminated completely from the natural groundwater by their absorptions on the Al-Zn hydroxide flocs, potentially because of their higher hydrophobicity compared with short-chain PFBS.


Assuntos
Ácidos Alcanossulfônicos/análise , Recuperação e Remediação Ambiental/métodos , Fluorocarbonos/análise , Poluentes Químicos da Água/análise , Ácidos Alcanossulfônicos/química , China , Eletrocoagulação , Fluorocarbonos/química , Água Subterrânea , Poluentes Químicos da Água/química
13.
Chemosphere ; 201: 303-309, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29525658

RESUMO

Increasing attentions have been paid on widespread perfluorooctanoic acid (PFOA) contaminations in the environment globally, especially in the industrial wastewaters and natural water bodies. In order to perform the treatment of PFOA simulated solution effectively with periodically reverse electrocoagulation (PREC), intensive studies were implemented on the conditions of treatment and adsorption mechanism. The optimal conversion rate of 1 mg L-1 PFOA treatment could be achieved 99.6% with Al-Zn electrode, when the voltage and stirring speed were set to 9 V and 500 rmp. The energy consumption of treating PFOA simulated aqueous solution at 20 min using Al-Zn electrodes was 43.93 kWh kg-1. In addition, the PREC technique was further applied to eliminate the PFOA contaminations in the natural groundwater, generating the conversion rate up to 79.4% at 60 min. Moreover, it was verified that PFOA contamination was adsorbed on the flocs of Zn0.61Al0.39(OH)2(CO3)0.195·xH2O by the detection of X-ray diffraction spectra (XRD) and Fourier transform infrared (FTIR) spectrum, the mainly mechanism was adsorption bringing and enmeshment, primarily resulting from the hydrophobic interaction of PFOA and Al-Zn hydroxide flocs.


Assuntos
Caprilatos/isolamento & purificação , Eletrocoagulação/métodos , Fluorocarbonos/isolamento & purificação , Purificação da Água/métodos , Adsorção , Caprilatos/química , Eletrodos , Fluorocarbonos/química , Água Subterrânea/química , Água/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
14.
Infect Genet Evol ; 33: 281-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25989376

RESUMO

HBV is characterized by a high genetic variability, which is the basis of its classification into eight genotypes (A-H). HBV infection is associated with different outcomes, from self-limiting acute hepatitis to active chronic hepatitis, asymptomatic carriage, and occult infection. The aim of this study was to analyze the genetic variability of HBV genotypes A and D isolates from 79 cases of self-limiting acute hepatitis and chronic hepatitis, in order to identify HBV variants associated with resolution or chronicity of acute HBV infection. The entire preS-S sequence and a fragment of 346 bp of the preC-C region, containing Enhancer II and Basal Core Promoter sequences, were analyzed. A phylogenetic analysis of preS/S region showed that the 45.45% (15/33) of isolates from acute hepatitis cases were genotype A compared to 8.69% (4/46) of chronic hepatitis cases. (p = 0.0002). Mutations associated with immune-escape (T131N, D144A/E, G145K), amino acid polymorphisms in "a determinant" domain of S protein and mutations/deletions in preC/C region were found in isolates from acute and chronic hepatitis B cases. In this study mutations/deletions in preS-S and preC-C regions, usually associated with fulminant acute hepatitis, advanced forms of liver disease and increased risk for HCC, were identified in HBV strains of genotype A and D obtained both from patients with self-limiting acute HBV infection and from persistent infected patients. This founding probably is due to the natural viral evolution under host immune response and to the circulation of a wide variety of HBV strains in our geographic area because of the ancient introduction of genotype D and the migrant fluxes from North Africa. Moreover, the analysis of circulation of new HBV antigenic variants is fundamental for the epidemiological surveys and for the evaluation of the impact of viral evolution on vaccine prophylaxis strategies.


Assuntos
Evolução Biológica , Variação Genética , Genótipo , Vírus da Hepatite B/genética , Hepatite B/virologia , Adulto , Idoso , Substituição de Aminoácidos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Filogenia , Polimorfismo Genético , Proteínas Virais/genética
15.
J Pharm Biomed Anal ; 87: 176-90, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23721687

RESUMO

The popularity of phosphodiesterase type 5 (PDE-5) enzyme inhibitors for the treatment of erectile dysfunction has led to the increase in prevalence of illicit sexual performance enhancement products. PDE-5 inhibitors, namely sildenafil, tadalafil and vardenafil, and their unapproved designer analogues are being increasingly used as adulterants in the herbal products and health supplements marketed for sexual performance enhancement. To date, more than 50 unapproved analogues of prescription PDE-5 inhibitors were found as adulterants in the literature. To avoid detection of such adulteration by standard screening protocols, the perpetrators of such illegal products are investing time and resources to synthesize exotic analogues and devise novel means for adulteration. A comprehensive review of conventional and advance analytical techniques to detect and characterize the adulterants is presented. The rapid identification and structural elucidation of unknown analogues as adulterants is greatly enhanced by the wide myriad of analytical techniques employed, including high performance liquid chromatography (HPLC), gas chromatography-mass spectrometry (GC-MS), liquid chromatography mass-spectrometry (LC-MS), nuclear magnetic resonance (NMR) spectroscopy, vibrational spectroscopy, liquid chromatography-Fourier transform ion cyclotron resonance-mass spectrometry (LC-FT-ICR-MS), liquid chromatograph-hybrid triple quadrupole linear ion trap mass spectrometer with information dependent acquisition, ultra high performance liquid chromatography-time of flight-mass spectrometry (UHPLC-TOF-MS), ion mobility spectroscopy (IMS) and immunoassay methods. The many challenges in detecting and characterizing such adulterants, and the need for concerted effort to curb adulteration in order to safe guard public safety and interest are discussed.


Assuntos
Técnicas de Química Analítica/métodos , Contaminação de Medicamentos/prevenção & controle , Inibidores da Fosfodiesterase 5/química , Carbolinas/análise , Carbolinas/química , Humanos , Imidazóis/análise , Imidazóis/química , Preparações Farmacêuticas/análise , Preparações Farmacêuticas/química , Preparações Farmacêuticas/normas , Inibidores da Fosfodiesterase 5/análise , Piperazinas/análise , Piperazinas/química , Preparações de Plantas/análise , Preparações de Plantas/química , Preparações de Plantas/normas , Purinas/análise , Purinas/química , Citrato de Sildenafila , Sulfonas/análise , Sulfonas/química , Tadalafila , Triazinas/análise , Triazinas/química , Dicloridrato de Vardenafila
16.
Artigo em Inglês | MEDLINE | ID: mdl-23959085

RESUMO

Numerous reports have highlighted the role of the endocannabinoid system in the addictive potential of MDMA (3,4-methylenedioxy-methamphetamine). A previous report showed that CB1 knockout (KOCB1) mice do not acquire MDMA self-administration, despite developing conditioned place preference (CPP). This contradiction could be due to the particular procedure of place conditioning used. The present work compares MDMA-induced CPP in KOCB1 mice using unbiased and biased procedures of place conditioning. In the unbiased procedure, MDMA induced CPP and reinstatement of the extinguished preference in wild type (WT) mice, but not in KOCB1 mice. In contrast, in a biased protocol of CPP, MDMA produced preference in both types of mice. The anxiolytic response induced by MDMA in the elevated plus maze (EPM) was observed only in KOCB1 mice and may have been responsible, at least partially, for the CPP in the biased procedure. A neurochemical analysis revealed that KOCB1 mice presented higher striatal DA and DOPAC levels in response to MDMA, but no alterations in their levels of monoamine transporters. In line with previous self-administration studies, our data suggest that CB1 receptors play an important role in the reinforcing effects of MDMA, and that the experimental procedure of CPP employed should be taken into account when drawing conclusions.


Assuntos
Condicionamento Operante/fisiologia , Alucinógenos/efeitos adversos , N-Metil-3,4-Metilenodioxianfetamina/efeitos adversos , Receptor CB1 de Canabinoide/metabolismo , Transtornos Relacionados ao Uso de Substâncias/patologia , Transtornos Relacionados ao Uso de Substâncias/fisiopatologia , Ácido 3,4-Di-Hidroxifenilacético/metabolismo , Análise de Variância , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Condicionamento Operante/efeitos dos fármacos , Modelos Animais de Doenças , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Ácido Homovanílico/metabolismo , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Knockout , Receptor CB1 de Canabinoide/deficiência , Reforço Psicológico , Fatores de Tempo
17.
World J Gastroenterol ; 18(39): 5570-5, 2012 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-23112549

RESUMO

AIM: To analysis the factors that predict the response to entecavir therapy in chronic hepatitis patients with hepatitis B virus (HBV) genotype C. METHODS: Fifty patients [hepatitis B e antigen (HBeAg)-negative:HBeAg-positive = 26:24] with HBV genotype C, who received naïve entecavir therapy for > 2 years, were analyzed. Patients who showed HBV DNA levels ≥ 3.0 log viral copies/mL after 2 years of entecavir therapy were designated as slow-responders, while those that showed < 3.0 log copies/mL were termed rapid-responders. Quantitative hepatitis B surface antigen (HBsAg) levels (qHBsAg) were determined by the Architect HBsAg QT immunoassay. Hepatitis B core-related antigen was detected by enzyme immunoassay. Pre-C and Core promoter mutations were determined using by polymerase chain reaction (PCR). Drug-resistance mutations were detected by the PCR-Invader method. RESULTS: At year 2, HBV DNA levels in all patients in the HBeAg-negative group were < 3.0 log copies/mL. In contrast, in the HBeAg-positive group, 41.7% were slow-responders, while 58.3% were rapid-responders. No entecavir-resistant mutants were detected in the slow-responders. When the pretreatment factors were compared between the slow- and rapid-responders; the median qHBsAg in the slow-responders was 4.57 log IU/mL, compared with 3.63 log IU/mL in the rapid-responders (P < 0.01). When the pretreatment factors predictive of HBV DNA-negative status at year 2 in all 50 patients were analyzed, HBeAg-negative status, low HBV DNA levels, and low qHBsAg levels were significant (P < 0.01). Multivariate analysis revealed that the low qHBsAg level was the most significant predictive factor (P = 0.03). CONCLUSION: Quantitation of HBsAg could be a useful indicator to predict response to entecavir therapy.


Assuntos
Antivirais/uso terapêutico , DNA Viral/sangue , Guanina/análogos & derivados , Hepatite B Crônica/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Guanina/uso terapêutico , Vírus da Hepatite B/genética , Vírus da Hepatite B/imunologia , Hepatite B Crônica/sangue , Hepatite B Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
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