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1.
Am J Trop Med Hyg ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38579704

RESUMO

Dengue fever (DF) is an endemic infectious tropical disease and is rapidly becoming a global problem. Dengue fever is caused by one of the four dengue virus (DENV) serotypes and is spread by the female Aedes mosquito. Clinical manifestations of DF may range from asymptomatic to life-threatening severe illness with conditions of hemorrhagic fever and shock. Early and precise diagnosis is vital to avoid mortality from DF. A different approach is required to combat DF because of the challenges with the vaccines currently available, which are nonspecific; each is capable of causing cross-reaction and disease-enhancing antibody responses against the residual serotypes. MicroRNAs (miRNAs) are known to be implicated in DENV infection and are postulated to be involved in most of the host responses. Thus, they might be a suitable target for new strategies against the disease. The involvement of miRNAs in cellular activities and pathways during viral infections has been explored under numerous conditions. Interestingly, miRNAs have also been shown to be involved in viral replication. In this review, we summarize the role of known miRNAs, specifically the role of miRNA Let-7c (miR-Let-7c), miR-133a, miR-30e, and miR-146a, in the regulation of DENV replication and their possible effects on the initial immune reaction.

2.
Rev Med Virol ; 34(2): e2529, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38520650

RESUMO

The discovery of anti-retroviral (ARV) drugs over the past 36 years has introduced various classes, including nucleoside/nucleotide reverse transcriptase inhibitors, non-nucleoside reverse transcriptase inhibitors, protease inhibitor, fusion, and integrase strand transfer inhibitors inhibitors. The introduction of combined highly active anti-retroviral therapies in 1996 was later proven to combat further ARV drug resistance along with enhancing human immunodeficiency virus (HIV) suppression. As though the development of ARV therapies was continuously expanding, the variation of action caused by ARV drugs, along with its current updates, was not comprehensively discussed, particularly for HIV-1 infection. Thus, a range of HIV-1 ARV medications is covered in this review, including new developments in ARV therapy based on the drug's mechanism of action, the challenges related to HIV-1, and the need for combination therapy. Optimistically, this article will consolidate the overall updates of HIV-1 ARV treatments and conclude the significance of HIV-1-related pharmacotherapy research to combat the global threat of HIV infection.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , HIV-1 , Humanos , Infecções por HIV/tratamento farmacológico , Inibidores da Transcriptase Reversa/farmacologia , Inibidores da Transcriptase Reversa/uso terapêutico , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Terapia Antirretroviral de Alta Atividade
3.
BMC Chem ; 16(1): 111, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36482476

RESUMO

Quinolone is a privileged scaffold in medicinal chemistry and 4-Quinolone-3-Carboxamides have been reported to harbor vast therapeutic potential. However, conversion of N-1 substituted 4-Quinolone 3-Carboxylate to its corresponding carbamates is highly restrictive. This motivated us to adopt a much simpler, scalable and efficient methodology for the synthesis of highly pure N-1 substituted 4- Quinolone-3-Carboxamides with excellent yields. Our adopted methodology not only provides a robust pathway for the convenient synthesis of N-1 substituted 4- Quinolone-3-Carboxamides which can then be explored for their therapeutic potential, this may also be adaptable for the derivatization of other such less reactive carboxylate species.

4.
Talanta ; 249: 123659, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35728452

RESUMO

Quartz crystal microbalance (QCM)-based biosensors are highly attractive as rapid diagnostic devices for detecting infectious diseases. However, the fabrication of QCM-based biosensors often involves tedious processes due to the poor stability of the biological recognition elements. In this work, the simple self-polymerisation of dopamine was used to functionalise the QCM crystal surface with a molecularly imprinted polydopamine (MIPDA) sensing film for detecting the hepatitis B core antigen (HBcAg), a serological biomarker of hepatitis B. Recognition cavities that complemented the size and shape of HBcAg were observed on the QCM crystal surface after functionalisation with the MIPDA film. The MIPDA-QCM biosensor showed a selective affinity for HBcAg, recording frequency responses up to 7.8 folds larger towards HBcAg compared to human serum albumin at the same analyte concentrations. The biosensor response was enhanced by using the optimal concentrations of 10 mg mL-1 of dopamine and 1 mg mL-1 of template for MIPDA film formation, resulting in a low detection limit (0.88 µg mL-1) that enables the detection of clinically relevant titres of HBcAg. The detection process could be completed within 10 min after sample loading without additional steps for signal amplification, highlighting the practical advantages of the MIPDA-QCM biosensor for point-of-care detection of hepatitis B.


Assuntos
Técnicas Biossensoriais , Hepatite B , Impressão Molecular , Técnicas Biossensoriais/métodos , Dopamina , Hepatite B/diagnóstico , Antígenos da Hepatite B , Antígenos do Núcleo do Vírus da Hepatite B , Humanos , Indóis , Impressão Molecular/métodos , Polímeros , Quartzo , Técnicas de Microbalança de Cristal de Quartzo
5.
Emerg Infect Dis ; 28(2): 475-477, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35076371

RESUMO

A new Getah virus (GETV) strain, B254, was isolated from Culex fuscocephalus mosquitoes captured at Mount Ophir, Malaysia, in 2012. Phylogenetic analyses revealed that GETV B254 is distinct from the old Malaysia GETV MM2021 strain but closely related to group IV GETV from Russia (LEIV16275Mag), China (YN12031), and Thailand (GETV/SW/Thailand/2017).


Assuntos
Alphavirus , Culex , Culicidae , Animais , Malásia/epidemiologia , Filogenia
6.
Am J Trop Med Hyg ; 106(1): 187-191, 2021 09 27.
Artigo em Inglês | MEDLINE | ID: mdl-34583338

RESUMO

This study explored the contribution of viral respiratory infections (VRIs) in dengue-like illness (DLI) patients and their distinguishing clinicolaboratory parameters. Two hundred DLI patients were prospectively recruited (July 1- October 1, 2019) from a community clinic in Southern Malaysia. Patients ≥ 18 years with acute fever and fulfilling the WHO criteria of probable dengue were recruited. They underwent blood testing: blood counts, rapid dengue tests (nonstructural antigen-1/IgM) and polymerase chain reaction (PCR) for dengue, Zika, chikungunya, and Leptospira. Nasopharyngeal swabs (NPSs) were collected for FilmArray®RP2plus testing. From the 200 NPSs, 58 respiratory viruses (RVs) were detected in 54 patients. Of the 96 dengue-confirmed cases, 86 had dengue mono-infection, and 10 were coinfected with RVs. Of the 104 nondengue, 44 were RV positive and 4 Leptospira positive. Zika and chikungunya virus were not detected. Overall, the etiological diagnosis was confirmed for 72% of patients. Clinicolaboratory parameters were compared between dengue mono-infection and VRI mono-infection. Patients with coinfections were excluded. Multiple logistic regression showed that recent household/neighborhood history of dengue (adjusted odds ratio [aOR]: 5.9, 95% CI = 1.7-20.7), leukopenia (aOR: 12.5, 95% CI = 2.6-61.4) and thrombocytopenia (aOR: 5.5, 95% CI = 1.3-23.0) predicted dengue. Inversely, rhinorrhoea (aOR: 0.1, 95% CI = 0.01-0.3) and cough (aOR: 0.3, 95% CI = 0.1-0.9) favored VRI. Thus, VRIs comprise many infections diagnosed initially as DLIs. Early clinicolaboratory parameters can guide physicians screen patients for further testing.


Assuntos
Dengue/complicações , Infecções Respiratórias/complicações , Viroses/complicações , Adulto , Feminino , Humanos , Malásia , Masculino , Estudos Prospectivos , Adulto Jovem
7.
Viruses ; 13(6)2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071712

RESUMO

Alphavirus non-structural proteins 1-4 (nsP1, nsP2, nsP3, and nsP4) are known to be crucial for alphavirus RNA replication and translation. To date, nsP3 has been demonstrated to mediate many virus-host protein-protein interactions in several fundamental alphavirus mechanisms, particularly during the early stages of replication. However, the molecular pathways and proteins networks underlying these mechanisms remain poorly described. This is due to the low genetic sequence homology of the nsP3 protein among the alphavirus species, especially at its 3' C-terminal domain, the hypervariable domain (HVD). Moreover, the nsP3 HVD is almost or completely intrinsically disordered and has a poor ability to form secondary structures. Evolution in the nsP3 HVD region allows the alphavirus to adapt to vertebrate and insect hosts. This review focuses on the putative roles and functions of indel, repetition, and duplication events that have occurred in the alphavirus nsP3 HVD, including characterization of the differences and their implications for specificity in the context of virus-host interactions in fundamental alphavirus mechanisms, which have thus directly facilitated the evolution, adaptation, viability, and re-emergence of these viruses.


Assuntos
Alphavirus/genética , Evolução Molecular , Interações Hospedeiro-Patógeno , Proteínas não Estruturais Virais/genética , Alphavirus/metabolismo , Animais , Sítios de Ligação , Linhagem Celular , Humanos , Camundongos , Proteínas não Estruturais Virais/metabolismo , Replicação Viral
8.
PLoS Negl Trop Dis ; 15(5): e0009445, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34014983

RESUMO

BACKGROUND: Dengue fever is the most common mosquito-borne infection worldwide where an expanding surveillance and characterization of this infection are needed to better inform the healthcare system. In this surveillance-based study, we explored the prevalence and distinguishing features of dengue fever amongst febrile patients in a large community-based health facility in southern peninsular Malaysia. METHODS: Over six months in 2018, we recruited 368 adults who met the WHO 2009 criteria for probable dengue infection. They underwent the following blood tests: full blood count, dengue virus (DENV) rapid diagnostic test (RDT), ELISA (dengue IgM and IgG), nested RT-PCR for dengue, multiplex qRT-PCR for Zika, Chikungunya and dengue as well as PCR tests for Leptopspira spp., Japanese encephalitis and West Nile virus. RESULTS: Laboratory-confirmed dengue infections (defined by positive tests in NS1, IgM, high-titre IgG or nested RT-PCR) were found in 167 (45.4%) patients. Of these 167 dengue patients, only 104 (62.3%) were positive on rapid diagnostic testing. Dengue infection was significantly associated with the following features: family or neighbours with dengue in the past week (AOR: 3.59, 95% CI:2.14-6.00, p<0.001), cutaneous rash (AOR: 3.58, 95% CI:1.77-7.23, p<0.001), increased temperature (AOR: 1.33, 95% CI:1.04-1.70, p = 0.021), leucopenia (white cell count < 4,000/µL) (AOR: 3.44, 95% CI:1.72-6.89, p<0.001) and thrombocytopenia (platelet count <150,000/µL)(AOR: 4.63, 95% CI:2.33-9.21, p<0.001). Dengue infection was negatively associated with runny nose (AOR: 0.47, 95% CI:0.29-0.78, p = 0.003) and arthralgia (AOR: 0.42, 95% CI:0.24-0.75, p = 0.004). Serotyping by nested RT-PCR revealed mostly mono-infections with DENV-2 (n = 64), DENV-1 (n = 32) and DENV-3 (n = 17); 14 co-infections occurred with DENV-1/DENV-2 (n = 13) and DENV-1/DENV-4 (n = 1). Besides dengue, none of the pathogens above were found in patients' serum. CONCLUSIONS: Acute undifferentiated febrile infections are a diagnostic challenge for community-based clinicians. Rapid diagnostic tests are increasingly used to diagnose dengue infection but negative tests should be interpreted with caution as they fail to detect a considerable proportion of dengue infection. Certain clinical features and haematological parameters are important in the clinical diagnosis of dengue infection.


Assuntos
Vírus da Dengue/imunologia , Dengue/diagnóstico , Dengue/epidemiologia , Adulto , Idoso , Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Contagem de Células Sanguíneas , Estudos Transversais , Dengue/virologia , Ensaio de Imunoadsorção Enzimática , Feminino , Febre/diagnóstico , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
9.
Malays J Med Sci ; 27(2): 10-20, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32788837

RESUMO

In light of the limited protection conferred by current influenza vaccines, immunisation using universal influenza vaccines has been proposed for protection against all or most influenza sub-types. The fundamental principle of universal influenza vaccines is based on conserved antigens found in most influenza strains, such as matrix 2, nucleocapsid, matrix 1 and stem of hemagglutinin proteins. These antigens trigger cross-protective immunity against different influenza strains. Many researchers have attempted to produce the conserved epitopes of these antigens in the form of peptides in the hope of generating universal influenza vaccine candidates that can broadly induce cross-reactive protection against influenza viral infections. However, peptide vaccines are poorly immunogenic when applied individually owing to their small molecular sizes. Hence, strategies, such as combining peptides as multi-epitope vaccines or presenting peptides on vaccinia virus particles, are employed. This review discusses the clinical and laboratory findings of several multi-epitope peptide vaccine candidates and vaccinia-based peptide vaccines. The majority of these vaccine candidates have reached the clinical trial phase. The findings in this study will indeed shed light on the applicability of universal influenza vaccines to prevent seasonal and pandemic influenza outbreaks in the near future.

10.
Eur J Med Chem ; 179: 423-448, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31265935

RESUMO

HIV infection is a major challenge to mankind and a definitive cure or a viable vaccine for HIV is still elusive. HIV-1 is constantly evolving and developing resistant against clinically used anti-HIV drugs thus posing serious hurdles in the treatment of HIV infection. This prompts the need to developed new anti-HIV drugs; preferentially adopting intelligent ways to counteract an evolving virus. Highly Active Anti-Retroviral Therapy (HAART): a strategy involving multiple targeting through various drugs has proven beneficial in the management of AIDS. However, it is a complex regimen with high drug load, increased risk of drug interactions and adverse effects, which lead to poor patient compliance. Reverse transcriptase (RT) and Integrase (IN) are two pivotal enzymes in HIV-1 lifecycle with high structural and functional analogy to be perceived as drug-able targets for novel dual-purpose inhibitors. Designed multi-functional ligand (DML) is a modern strategy by which multiple targets can be exploited using a single chemical entity. A single chemical entity acting on multiple targets can be much more effective than a complex multi-drug regimen. The development of such multifunctional ligands is highly valued in anti-HIV drug discovery with the proposed advantage of being able to stop two or more stages of viral replication cycle. This review will encompass the evolution of the RT-IN dual inhibitory scaffolds reported so far and the contribution made by the leading research groups over the years in this field.


Assuntos
Fármacos Anti-HIV/farmacologia , Inibidores de Integrase de HIV/farmacologia , Integrase de HIV/metabolismo , Transcriptase Reversa do HIV/antagonistas & inibidores , HIV-1/efeitos dos fármacos , Inibidores da Transcriptase Reversa/farmacologia , Fármacos Anti-HIV/química , Inibidores de Integrase de HIV/química , Transcriptase Reversa do HIV/metabolismo , Humanos , Estrutura Molecular , Inibidores da Transcriptase Reversa/química
11.
Sci Rep ; 9(1): 4805, 2019 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-30886246

RESUMO

Besides causing mild hand, foot and mouth infections, Enterovirus A71 (EV-A71) is associated with neurological complications and fatality. With concerns about rising EV-A71 virulence, there is an urgency for more effective vaccines. The live attenuated vaccine (LAV) is a more valuable vaccine as it can elicit both humoral and cellular immune responses. A miRNA-based vaccine strain (pIY) carrying let-7a and miR-124a target genes in the EV-A71 genome which has a partial deletion in the 5'NTR (∆11 bp) and G64R mutation (3Dp°l) was designed. The viral RNA copy number and viral titers of the pIY strain were significantly lower in SHSY-5Y cells that expressed both let-7a and miR-124a. Inhibition of the cognate miRNAs expressed in RD and SHSY-5Y cells demonstrated de-repression of viral mRNA translation. A previously constructed multiply mutated strain, MMS and the pIY vaccine strain were assessed in their ability to protect 4-week old mice from hind limb paralysis. The MMS showed higher amounts of IFN-γ ex vivo than the pIY vaccine strain. There was absence of EV-A71 antigen in the skeletal muscles and spinal cord micrographs of mice vaccinated with the MMS and pIY strains. The MMS and pIY strains are promising LAV candidates developed against severe EV-A71 infections.


Assuntos
Enterovirus Humano A/imunologia , Doença de Mão, Pé e Boca/prevenção & controle , Vacinas Virais/administração & dosagem , Virulência/genética , Animais , Antígenos Virais/análise , Antígenos Virais/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Enterovirus Humano A/genética , Enterovirus Humano A/isolamento & purificação , Genoma Viral/genética , Doença de Mão, Pé e Boca/diagnóstico , Doença de Mão, Pé e Boca/imunologia , Doença de Mão, Pé e Boca/virologia , Humanos , Imunidade Celular , Imunidade Humoral , Imunogenicidade da Vacina , Camundongos , MicroRNAs/genética , Mutação , RNA Viral/isolamento & purificação , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/genética , Vacinas Atenuadas/imunologia , Carga Viral , Vacinas Virais/genética , Vacinas Virais/imunologia , Replicação Viral/imunologia
12.
Vector Borne Zoonotic Dis ; 19(7): 549-552, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30668248

RESUMO

Background: There is an escalation of frequency and magnitude of dengue epidemics in Malaysia, with a concomitant increase in patient hospitalization. Prolonged hospitalization (PH) due to dengue virus (DENV) infections causes considerable socioeconomic burden. Early identification of patients needing PH could optimize resource consumption and reduce health care costs. This study aims to identify clinicopathological factors present on admission that are associated with PH among patients with DENV infections. Methods: This study was conducted in a tertiary referral hospital in Southern Malaysia. Relevant clinical and laboratory data upon admission were retrieved from medical records of 253 consecutive DENV nonstructural protein 1 (NS1) antigen and PCR-positive hospitalized patients. The DENV serotype present in each patient was determined. Patients were stratified based on duration of hospital stay (<4 vs. ≥4 days). Data were analyzed using IBM® SPSS® 25.0. Multivariate logistic regression was performed to examine the association between PH and admission parameters. Results: Of 253 DENV hospitalized patients, 95 (37.5%) had PH (≥4 days). The mean duration of hospital stay was 3.43 ± 2.085 days (median = 3 days, interquartile range = 7 days). Diabetes mellitus (adjusted odds ratio [AOR] = 6.261, 95% confidence interval [CI] = 2.130-18.406, p = 0.001), DENV-2 serotype (AOR = 2.581, 95% CI = 1.179-5.650, p = 0.018), duration of fever ≤4 days (AOR = 2.423, 95% CI = 0.872-6.734, p = 0.09), and a shorter preadmission fever duration (AOR = 0.679, 95% CI = 0.481-0.957, p = 0.027) were independently associated with PH. However, PH was not found to be associated with symptoms on admission, secondary DENV infections or platelet count, hematocrit, or liver enzyme levels on admission. Conclusions: Early identification of these factors at presentation may alert clinicians to anticipate and recognize challenges in treating such patients, leading to more focused management plans that may shorten the duration of hospitalization.


Assuntos
Vírus da Dengue , Dengue/fisiopatologia , Febre , Tempo de Internação/estatística & dados numéricos , Adolescente , Adulto , Idoso , Criança , Dengue/sangue , Dengue/complicações , Complicações do Diabetes , Feminino , Humanos , Modelos Logísticos , Malásia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sorogrupo , Centros de Atenção Terciária , Proteínas não Estruturais Virais/genética
13.
PLoS One ; 13(7): e0200698, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30016369

RESUMO

Both obesity and DENV infections are growing public health concerns that have far-ranging socioeconomic effects, especially in developing countries. Despite the increasing prevalence of these conditions, there is a scarcity of data investigating the potential relationships between these two entities. Our study aims to examine the influence of obesity on various clinical and laboratory parameters amongst patients with DENV infections. A total of 335 hospitalized patients aged >12 years who were DENV non-structural protein 1 (NS1) antigen-positive were enrolled in this study. Clinical and laboratory variables were compared between patients with and without obesity. Multivariate analysis showed that the following admission clinical findings and laboratory results were independently associated with obesity; chills and rigors (AOR:2.653, 95% CI: 1.286-5.474), higher temperature (AOR:1.485, 95% CI: 1.080-2.042), higher systolic BP (AOR:1.057, 95% CI:1.037-1.078), raised haematocrit (AOR: 1.953, 95% CI: 1.010-3.778), elevated creatinine (AOR:3.504, 95% CI:1.351-9.008) and elevated ALT (AOR: 4.146, 95% CI:1.878-9.154). Obesity was found to be significantly associated with hospitalization >3 days (AOR: 1.990, 95% CI: 1.134-3.494) and the presence of increasing haematocrit with decreasing platelets (AOR: 2.134, 95% CI = 1.235-3.688). Serial assessment of laboratory data revealed that peak haematocrit was significantly higher and nadir platelets levels were significantly lower in obese patients. Both peak and admission levels of leukocyte counts, AST, ALT and creatinine were significantly higher in the obese group. Conversely, both admission and nadir albumin levels were lower for the obese group, although only nadir albumin levels achieved statistical significance. These findings support closer clinical monitoring of obese patients who present with DENV infections, as this patient cohort may possess an increased tendency towards developing more severe clinical manifestations of DENV infections as compared to non-obese patients.


Assuntos
Pressão Sanguínea , Vírus da Dengue , Dengue , Obesidade , Adolescente , Adulto , Idoso , Dengue/sangue , Dengue/complicações , Dengue/fisiopatologia , Feminino , Hematócrito , Hospitalização , Humanos , Contagem de Leucócitos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/complicações , Obesidade/fisiopatologia , Obesidade/virologia , Contagem de Plaquetas
14.
Infect Dis Poverty ; 7(1): 1, 2018 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-29335021

RESUMO

BACKGROUND: The frequency and magnitude of dengue epidemics continue to increase exponentially in Malaysia, with a shift in the age range predominance toward adults and an expansion to rural areas. Despite this, information pertaining to the extent of transmission of dengue virus (DENV) in the rural community is lacking. This community-based pilot study was conducted to establish DENV seroprevalence amongst healthy adults in a rural district in Southern Malaysia, and to identify influencing factors. METHODS: In this study undertaken between April and May 2015, a total of 277 adult participants were recruited from households across three localities in the Sungai Segamat subdistrict in Segamat district. Sera were tested for immunoglobulin G (IgG) (Panbio® Dengue Indirect IgG ELISA/high-titer capture) and immunoglobulin M (IgM) (Panbio®) antibodies. The plaque reduction neutralization test (PRNT) was conducted on random samples of IgG-positive sera for further confirmation. Medical history and a recall of previous history of dengue were collected through interviews, whereas sociodemographic information was obtained from an existing database. RESULTS: The overall seroprevalence for DENV infection was 86.6% (240/277) (95% CI: 83-91%). Serological evidence of recent infection (IgM/high-titer capture IgG) was noted in 11.2% (31/277) of participants, whereas there was evidence of past infection in 75.5% (209/277) of participants (indirect IgG minus recent infections). The PRNT assay showed that the detected antibodies were indeed specific to DENV. The multivariate analysis showed that the older age group was significantly associated with past DENV infections. Seropositivity increased with age; 48.5% in the age group of <25 years to more than 85% in age group of >45 years (P < 0.001). No associations with occupation, study site, housing type, comorbidity, educational level, and marital status were observed, although the latter two were statistically significant in the univariate analysis. None of the studied factors were significantly associated with recent DENV infections in the multivariate analysis, although there was a pattern suggestive of recent outbreak in two study sites populated predominately by Chinese people. The majority of infections did not give rise to recognizable disease (either asymptomatic or nonspecific symptoms) as only 12.9% of participants (31/240) recalled having dengue in the past. CONCLUSIONS: The predominantly rural community under study had a very high previous exposure to dengue. The finding of a high proportion of unreported cases possibly due to subclinical infections underscores the need for enhanced surveillance and control methods. This finding also has implications for measuring disease burden, understanding transmission dynamics, and hypothesizing effects on DENV vaccine efficacy and uptake.


Assuntos
Anticorpos Antivirais/sangue , Vírus da Dengue/imunologia , Dengue/epidemiologia , Dengue/imunologia , Estudos Soroepidemiológicos , Adulto , Fatores Etários , Dengue/sangue , Dengue/transmissão , Vírus da Dengue/isolamento & purificação , Surtos de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Voluntários Saudáveis , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Características de Residência , População Rural
15.
Proteomes ; 5(3)2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28895884

RESUMO

Septin forms a conserved family of cytoskeletal guanosine triphosphate (GTP) binding proteins that have diverse roles in protein scaffolding, vesicle trafficking, and cytokinesis. The involvement of septins in infectious viral disease pathogenesis has been demonstrated by the upregulation of SEPT5 protein and its mRNA in brain tissues of H5N1-infected chickens, thus, providing evidence for the potential importance of this protein in the pathogenesis of neurovirulence caused by the avian influenza virus. In this study, cloning, expression, and purification of Gallus gallus SEPT5 protein was performed in Escherichia coli. The SEPT5 gene was inserted into the pRSETB expression vector, transformed in the E. coli BL21 (DE3) strain and the expression of SEPT5 protein was induced by IPTG. The SEPT5 protein was shown to be authentic as it was able to be pulled down by a commercial anti-SEPT5 antibody in a co-immunoprecipitation assay. In vivo aggregation of the recombinant protein was limited by cultivation at a reduced temperature of 16 °C. Using co-immunoprecipitation techniques, the purified recombinant SEPT5 protein was used to pull down host's interacting or binding proteins, i.e., proteins of brains of chickens infected with the H5N1 influenza virus. Interacting proteins, such as CRMP2, tubulin proteins, heat-shock proteins and other classes of septins were identified using LCMS/MS. Results from this study suggest that the codon-optimized SEPT5 gene can be efficiently expressed in the E. coli bacterial system producing authentic SEPT5 protein, thus, enabling multiple host's proteins to interact with the SEPT5 protein.

16.
Platelets ; 28(7): 724-727, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28287000

RESUMO

Severe thrombocytopenia is common in dengue virus (DENV) infections. However, studies focusing on the role of profound thrombocytopenia (PT) (nadir platelet counts ≤ 20 000/mm3) in DENV infections are scarce. This study aims to identify the associated features and outcome of DENV patients with PT. It involves 237 adult hospitalized patients who were DENV PCR positive. The presence of comorbidity (AOR = 4.625; 95% CI = 1.113-19.230), higher admission hematocrit (AOR = 1.213; 95% CI = 1.067-1.379), lower admission albumin (AOR = 0.870; 95% CI = 0.766-0.988) and lower admission platelets (AOR = 0.980; 95% CI = 0.969-0.991) was associated with platelets ≤ 20 000/mm3 in multivariate logistic regression. PT was not affected by DENV serotypes, coinfections and secondary DENV infections. Patients with PT had significantly higher risk of experiencing warning signs (AOR = 3.709, 95% CI = 1.089-12.634) and longer hospital stay (AOR = 1.943, 95% CI = 1.010-3.774). However, severe dengue disease, hemorrhagic manifestations and need for intensive care were not significantly associated with PT.


Assuntos
Plaquetas/patologia , Hemorragia/sangue , Dengue Grave/sangue , Trombocitopenia/sangue , Adolescente , Adulto , Idoso , Plaquetas/metabolismo , Vírus da Dengue/patogenicidade , Vírus da Dengue/fisiologia , Feminino , Hematócrito , Hemorragia/patologia , Hospitalização , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Contagem de Plaquetas , Estudos Retrospectivos , Fatores de Risco , Albumina Sérica/metabolismo , Dengue Grave/complicações , Dengue Grave/patologia , Índice de Gravidade de Doença , Trombocitopenia/complicações , Trombocitopenia/patologia
17.
Sci Rep ; 6: 38692, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27995961

RESUMO

We report the computational and experimental efforts in the design and synthesis of novel neuraminidase (NA) inhibitors from ferulic acid and vanillin. Two proposed ferulic acid analogues, MY7 and MY8 were predicted to inhibit H1N1 NA using molecular docking. From these two analogues, we designed, synthesised and evaluated the biological activities of a series of ferulic acid and vanillin derivatives. The enzymatic H1N1 NA inhibition assay showed MY21 (a vanillin derivative) has the lowest IC50 of 50 µM. In contrast, the virus inhibition assay showed MY15, a ferulic acid derivative has the best activity with the EC50 of ~0.95 µM. Modelling studies further suggest that these predicted activities might be due to the interactions with conserved and essential residues of NA with ΔGbind values comparable to those of oseltamivir and zanamivir, the two commercial NA inhibitors.


Assuntos
Benzaldeídos/síntese química , Benzaldeídos/farmacologia , Bioensaio , Ácidos Cumáricos/síntese química , Ácidos Cumáricos/farmacologia , Vírus da Influenza A Subtipo H1N1/enzimologia , Modelos Moleculares , Neuraminidase/antagonistas & inibidores , Antivirais/síntese química , Antivirais/química , Antivirais/farmacologia , Benzaldeídos/química , Sítios de Ligação , Ácidos Cumáricos/química , Cristalografia por Raios X , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Concentração Inibidora 50 , Simulação de Acoplamento Molecular , Neuraminidase/química , Neuraminidase/metabolismo
18.
BMC Infect Dis ; 16(1): 406, 2016 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-27514512

RESUMO

BACKGROUND: The co-circulation of 4 DENV serotypes in geographically expanding area, has resulted in increasing occurrence of DENV co-infections. However, studies assessing the clinical impact of DENV co-infections have been scarce and have involved small number of patients. This study explores the impact of DENV co-infection on clinical manifestations and laboratory parameters. METHODS: This retrospective study involved consecutive hospitalized patients with non-structural protein 1 (NS1) antigen positivity during an outbreak (Jan to April 2014). Multiplex RT-PCR was performed directly on NS1 positive serum samples to detect and determine the DENV serotypes. All PCR-positive serum samples were inoculated onto C6/36 cells. Multiplex PCR was repeated on the supernatant of the first blind passage of the serum-infected cells. Random samples of supernatant from the first passage of C6/36 infected cells were subjected to whole genome sequencing. Clinical and laboratory variables were compared between patients with and without DENV co-infections. RESULTS: Of the 290 NS1 positive serum samples, 280 were PCR positive for DENV. Medical notes of 262 patients were available for analysis. All 4 DENV serotypes were identified. Of the 262 patients, forty patients (15.3 %) had DENV co-infections: DENV-1/DENV-2(85 %), DENV-1/DENV-3 (12.5 %) and DENV-2/DENV-3 (2.5 %). Another 222 patients (84.7 %) were infected with single DENV serotype (mono-infection), with DENV- 1 (76.6 %) and DENV- 2 (19.8 %) predominating. Secondary dengue infections occurred in 31.3 % patients. Whole genome sequences of random samples representing DENV-1 and DENV-2 showed heterogeneity amongst the DENVs. Multivariate analysis revealed that pleural effusion and the presence of warning signs were significantly higher in the co-infected group, both in the overall and subgroup analysis. Diarrhoea was negatively associated with co-infection. Additionally, DENV-2 co-infected patients had higher frequency of patients with severe thrombocytopenia (platelet count < 50,000/mm(3)), whereas DENV-2 mono-infections presented more commonly with myalgia. Elevated creatinine levels were more frequent amongst the co-infected patients in univariate analysis. Haemoconcentration and haemorrhagic manifestations were not higher amongst the co-infected patients. Serotypes associated with severe dengue were: DENV-1 (n = 9), DENV-2 (n = 1), DENV-3 (n = 1) in mono-infected patients and DENV-1/DENV-2 (n = 5) and DENV-1/DENV-3 (n = 1) amongst the co-infected patients. CONCLUSION: DENV co-infections are not uncommon in a hyperendemic region and co-infected patients are skewed towards more severe clinical manifestations compared to mono-infected patients.


Assuntos
Vírus da Dengue/genética , Dengue/patologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Coinfecção/epidemiologia , Coinfecção/patologia , Coinfecção/virologia , Dengue/diagnóstico , Dengue/epidemiologia , Dengue/virologia , Vírus da Dengue/classificação , Vírus da Dengue/isolamento & purificação , Surtos de Doenças , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Análise Multivariada , Razão de Chances , Filogenia , RNA Viral/isolamento & purificação , RNA Viral/metabolismo , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sorogrupo , Índice de Gravidade de Doença , Proteínas não Estruturais Virais/genética , Adulto Jovem
19.
J Invertebr Pathol ; 136: 10-22, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26880158

RESUMO

The world production of shrimp such as the Malaysian giant freshwater prawn, Macrobrachium rosenbergii is seriously affected by the white spot syndrome virus (WSSV). There is an urgent need to understand the host pathogen interaction between M. rosenbergii and WSSV which will be able to provide a solution in controlling the spread of this infectious disease and lastly save the aquaculture industry. Now, using Next Generation Sequencing (NGS), we will be able to capture the response of the M. rosenbergii to the pathogen and have a better understanding of the host defence mechanism. Two cDNA libraries, one of WSSV-challenged M. rosenbergii and a normal control one, were sequenced using the Illumina HiSeq™ 2000 platform. After de novo assembly and clustering of the unigenes from both libraries, 63,584 standard unigenes were generated with a mean size of 698bp and an N50 of 1137bp. We successfully annotated 35.31% of all unigenes by using BLASTX program (E-value <10-5) against NCBI non-redundant (Nr), Swiss-Prot, Kyoto Encyclopedia of Genes and Genome pathway (KEGG) and Orthologous Groups of proteins (COG) databases. Gene Ontology (GO) assessment was conducted using BLAST2GO software. Differentially expressed genes (DEGs) by using the FPKM method showed 8443 host genes were significantly up-regulated whereas 5973 genes were significantly down-regulated. The differentially expressed immune related genes were grouped into 15 animal immune functions. The present study showed that WSSV infection has a significant impact on the transcriptome profile of M. rosenbergii's hepatopancreas, and further enhanced the knowledge of this host-virus interaction. Furthermore, the high number of transcripts generated in this study will provide a platform for future genomic research on freshwater prawns.


Assuntos
Infecções por Vírus de DNA/veterinária , Hepatopâncreas/imunologia , Palaemonidae/virologia , Vírus da Síndrome da Mancha Branca 1 , Animais , Infecções por Vírus de DNA/genética , Infecções por Vírus de DNA/imunologia , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Palaemonidae/genética , Palaemonidae/imunologia , Filogenia , Reação em Cadeia da Polimerase em Tempo Real , Transcriptoma
20.
Molecules ; 20(7): 11830-60, 2015 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-26132907

RESUMO

In an effort to study curcumin analogues as an alternative to improve the therapeutic efficacy of curcumin, we screened the cytotoxic potential of four diarylpentanoids using the HeLa and CaSki cervical cancer cell lines. Determination of their EC50 values indicated relatively higher potency of 1,5-bis(2-hydroxyphenyl)-1,4-pentadiene-3-one (MS17, 1.03 ± 0.5 µM; 2.6 ± 0.9 µM) and 1,5-bis(4-hydroxy-3-methoxyphenyl)-1,4-pentadiene-3-one (MS13, 2.8 ± 0.4; 6.7 ± 2.4 µM) in CaSki and HeLa, respectively, with significantly greater growth inhibition at 48 and 72 h of treatment compared to the other analogues or curcumin. Based on cytotoxic and anti-proliferative activity, MS17 was selected for comprehensive apoptotic studies. At 24 h of treatment, fluorescence microscopy detected that MS17-exposed cells exhibited significant morphological changes consistent with apoptosis, corroborated by an increase in nucleosomal enrichment due to DNA fragmentation in HeLa and CaSki cells and activation of caspase-3 activity in CaSki cells. Quantitative real-time PCR also detected significant down-regulation of HPV18- and HPV16-associated E6 and E7 oncogene expression following treatment. The overall data suggests that MS17 treatment has cytotoxic, anti-proliferative and apoptosis-inducing potential in HPV-positive cervical cancer cells. Furthermore, its role in down-regulation of HPV-associated oncogenes responsible for cancer progression merits further investigation into its chemotherapeutic role for cervical cancer.


Assuntos
Apoptose/efeitos dos fármacos , Curcumina/análogos & derivados , Proteínas de Ligação a DNA/genética , Regulação para Baixo/efeitos dos fármacos , Proteínas Oncogênicas Virais/genética , Oncogenes , Proteínas E7 de Papillomavirus/genética , Proteínas Repressoras/genética , Neoplasias do Colo do Útero/virologia , Divisão Celular/efeitos dos fármacos , Curcumina/farmacologia , Feminino , Humanos , Microscopia de Fluorescência , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
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