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1.
Genes Cells ; 29(7): 599-607, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782708

RESUMO

WT 9-12 is one of the cell lines commonly used for autosomal dominant polycystic kidney disease (ADPKD) studies. Previous studies had described the PKD gene mutations and polycystin expression in WT 9-12. Nonetheless, the mutations occurring in other ADPKD-associated genes have not been investigated. This study aims to revisit these mutations and protein profile of WT 9-12. Whole genome sequencing verified the presence of truncation mutation at amino acid 2556 (Q2556X) in PKD1 gene of WT 9-12. Besides, those variations with high impacts included single nucleotide polymorphisms (rs8054182, rs117006360, and rs12925771) and insertions and deletions (InDels) (rs145602984 and rs55980345) in PKD1L2; InDel (rs1296698195) in PKD1L3; and copy number variations in GANAB. Protein profiles generated from the total proteins of WT 9-12 and HK-2 cells were compared using isobaric tags for relative and absolute quantitation (iTRAQ) analysis. Polycystin-1 was absent in WT 9-12. The gene ontology enrichment and reactome pathway analyses revealed that the upregulated and downregulated proteins of WT 9-12 relative to HK-2 cell line leaded to signaling pathways related to immune response and amino acid metabolism, respectively. The ADPKD-related mutations and signaling pathways associated with differentially expressed proteins in WT 9-12 may help researchers in cell line selection for their studies.


Assuntos
Mutação , Rim Policístico Autossômico Dominante , Canais de Cátion TRPP , Rim Policístico Autossômico Dominante/genética , Rim Policístico Autossômico Dominante/metabolismo , Rim Policístico Autossômico Dominante/patologia , Humanos , Linhagem Celular , Canais de Cátion TRPP/genética , Canais de Cátion TRPP/metabolismo , Polimorfismo de Nucleotídeo Único , Variações do Número de Cópias de DNA
2.
Neuropathol Appl Neurobiol ; 48(6): e12828, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35689364

RESUMO

OBJECTIVES: Acute Nipah (NiV) encephalitis is characterised by a dual pathogenetic mechanism of neuroglial infection and ischaemia-microinfarction associated with vasculitis-induced thrombotic occlusion. We investigated the contributions of these two mechanisms in fatal cases. MATERIALS AND METHODS: We analysed brain tissues (cerebrum, brainstem and cerebellum) from 15 autopsies using light microscopy, immunohistochemistry (IHC), in situ hybridisation and quantitative methods. RESULTS: Three types of discrete plaque-like parenchymal lesions were identified: Type 1 with neuroglial IHC positivity for viral antigens and minimal or no necrosis; Type 2 with neuroglial immunopositivity and necrosis; and Type 3 with necrosis but no viral antigens. Most viral antigen/RNA-positive cells were neurons. Cerebral glial immunopositivity was rare, suggesting that microinfarction played a more important role in white matter injury. Type 1 lesions were also detected in the brainstem and cerebellum, but the differences between cerebral cortex and these two regions were not statistically significant. In the cerebral cortex, Type 1 lesions overwhelmingly predominated, and only 14% Type 1 vs 69% Type 2 lesions were associated with thrombosis. This suggests that neuronal infection as a mechanism of pathogenesis was more important than microinfarction, both in general and in Type 1 lesions in particular. Between the 'early' group (<8-day fever) and the 'late' group (≥8-day fever), there was a decrease of Type 1 and Type 2 lesions with a concomitant increase of Type 3 lesions, suggesting the latter possibly represented late-stage microinfarction and/or neuronal infection. CONCLUSION: Neuronal infection appears to play a more important role than vasculopathy-induced microinfarction in acute NiV encephalitis.


Assuntos
Encefalite , Infecções por Henipavirus , Encefalite/patologia , Infecções por Henipavirus/patologia , Humanos , Imuno-Histoquímica , Neurônios/patologia
3.
Food Technol Biotechnol ; 60(1): 80-88, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35440880

RESUMO

Research background: Tiger milk mushroom (Lignosus rhinocerus) is a medicinal mushroom that is geographically distributed in the region of South China, Thailand, Malaysia, Indonesia, Philippines and Papua New Guinea. Consumption of its sclerotium has been reported to treat various ailments. However, its anticancer potential towards oral cancer cell lines is yet to be determined considering the traditional method of its consumption by biting/chewing of the sclerotium. Experimental approach: Mushroom sclerotial powder of cultivar TM02® was extracted and fractionated in a chromatographic column prior to cytotoxicity testing against a panel of human oral cancer cell lines. The capability of the identified bioactive fraction in regulating several molecules associated with its tumour necrosis factor (TNF) pathway was investigated. Results and conclusions: 2,5-Diphenyl-2H-tetrazolium bromide (MTT) proliferation assay indicated that cell lines ORL-48 (derived from gingiva), ORL-188 (derived from the tongue) and ORL-204 (derived from buccal mucosa) were inhibited by cold water extract of L. rhinocerus sclerotia and its high-molecular-mass fraction (HMM) in varying degrees with ORL-204 being most affected. Hence, the treatment of ORL-204 with HMM mushroom extract was further investigated. HMM mushroom extract induced apoptosis and G0/G1 phase cell cycle arrest through caspase-3/7 cleavage. Activities of MIP2 and COX-2 were downregulated by 0.2- and 4.6-fold respectively in the HMM mushroom extract-treated ORL-204 cells. Novelty and scientific contribution: Using ORL-204, we showed that HMM mushroom extract may act via the TNF pathway at various network sites as a potential dietary compound for cancer prevention and natural adjunct therapeutic to conventional cancer treatment.

4.
PLoS Pathog ; 15(11): e1007863, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31730673

RESUMO

Enterovirus A71 (EV-A71) causes hand, foot and mouth disease epidemics with neurological complications and fatalities. However, the neuropathogenesis of EV-A71 remains poorly understood. In mice, adaptation and virulence determinants have been mapped to mutations at VP2-149, VP1-145 and VP1-244. We investigate how these amino acids alter heparin-binding phenotype and shapes EV-A71 virulence in one-day old mice. We constructed six viruses with varying residues at VP1-98, VP1-145 (which are both heparin-binding determinants) and VP2-149 (based on the wild type 149K/98E/145Q, termed KEQ) to generate KKQ, KKE, KEE, IEE and IEQ variants. We demonstrated that the weak heparin-binder IEE was highly lethal in mice. The initially strong heparin-binding IEQ variant acquired an additional mutation VP1-K244E, which confers weak heparin-binding phenotype resulting in elevated viremia and increased virus antigens in mice brain, with subsequent high virulence. IEE and IEQ-244E variants inoculated into mice disseminated efficiently and displayed high viremia. Increasing polymerase fidelity and impairing recombination of IEQ attenuated the virulence, suggesting the importance of population diversity in EV-A71 pathogenesis in vivo. Combining in silico docking and deep sequencing approaches, we inferred that virus population diversity is shaped by electrostatic interactions at the five-fold axis of the virus surface. Electrostatic surface charges facilitate virus adaptation by generating poor heparin-binding variants for better in vivo dissemination in mice, likely due to reduced adsorption to heparin-rich peripheral tissues, which ultimately results in increased neurovirulence. The dynamic switching between heparin-binding and weak heparin-binding phenotype in vivo explained the neurovirulence of EV-A71.


Assuntos
Encéfalo/virologia , Proteínas do Capsídeo/metabolismo , Enterovirus Humano A/genética , Infecções por Enterovirus/virologia , Enterovirus/genética , Heparina/metabolismo , Fatores de Virulência/metabolismo , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Proteínas do Capsídeo/química , Proteínas do Capsídeo/genética , Enterovirus/química , Infecções por Enterovirus/epidemiologia , Infecções por Enterovirus/metabolismo , Heparina/química , Interações Hospedeiro-Patógeno , Humanos , Camundongos , Camundongos Endogâmicos ICR , Mutação , Fenótipo , Eletricidade Estática , Células Tumorais Cultivadas , Virulência , Fatores de Virulência/química , Fatores de Virulência/genética , Replicação Viral
5.
Clin Exp Nephrol ; 25(11): 1163-1172, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34254206

RESUMO

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a monogenic kidney disorder that impairs renal functions progressively leading to kidney failure. The disease affects between 1:400 and 1:1000 ratio of the people worldwide. It is caused by the mutated PKD1 and PKD2 genes which encode for the defective polycystins. Polycystins mimic the receptor protein or protein channel and mediate aberrant cell signaling that causes cystic development in the renal parenchyma. The cystic development is driven by the increased cyclic AMP stimulating fluid secretion and infinite cell growth. In recent years, natural product-derived small molecules or drugs targeting specific signaling pathways have caught attention in the drug discovery discipline. The advantages of natural products over synthetic drugs enthusiast researchers to utilize the medicinal benefits in various diseases including ADPKD. CONCLUSION: Overall, this review discusses some of the previously studied and reported natural products and their mechanisms of action which may potentially be redirected into ADPKD.


Assuntos
Chalconas/farmacologia , Flavanonas/farmacologia , Metformina/farmacologia , Extratos Vegetais/farmacologia , Rim Policístico Autossômico Dominante/tratamento farmacológico , Quercetina/farmacologia , Antioxidantes/farmacologia , Curcumina/farmacologia , Diterpenos/farmacologia , Diterpenos do Tipo Caurano/farmacologia , Emodina/farmacologia , Compostos de Epóxi/farmacologia , Antagonistas de Estrogênios/farmacologia , Humanos , Hipoglicemiantes/farmacologia , Fenantrenos/farmacologia , Extratos Vegetais/uso terapêutico , Inibidores de Proteínas Quinases/farmacologia , Resveratrol/farmacologia
6.
Lab Invest ; 100(9): 1262-1275, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32601355

RESUMO

Coxsackievirus A16 (CV-A16) is one of the major causes of mild and self-limiting hand-foot-and-mouth disease (HFMD) in young children, which may occasionally leads to serious neurological complications. In this study, we had developed a novel, consistent, orally infected CV-A16 HFMD hamster model with encephalomyelitis. Four groups of 7-day-old hamsters in a kinetic study were orally infected with mouse-adapted CV-A16 strains and sacrificed at 1-4 days post infection (dpi), respectively. Tissues were studied by light microscopy, immunohistochemistry to detect viral antigens, in situ hybridization to detect viral RNA, and by viral titration. In a separate transmission experiment, orally infected index hamsters were housed together with contact hamsters to investigate oral and fecal viral shedding by virus culture and reverse transcription polymerase chain reaction (RT-PCR). At severe infection/death endpoints, index and contact hamster infection were also histopathologically analyzed. In the kinetic study, infected hamsters developed signs of infection at 4 dpi. Viral antigens/RNA were localized to brainstem (medulla/pons; reticular formation and motor trigeminal nucleus) and spinal cord anterior horn neurons, oral squamous epithelia and epidermis from 3 to 4 dpi. Salivary and lacrimal glands, myocardium, brown adipose tissue, intestinal smooth muscle, and skeletal muscle infection was also demonstrated. Viremia at 1 dpi and increasing viral titers in various tissues were observed from 2 dpi. In the transmission study, all contact hamsters developed disease 3-5 days later than index hamsters, but demonstrated similar histopathological findings at endpoint. Viral culture and RT-PCR positive oral washes and feces confirmed viral shedding. Our hamster model, orally infected by the natural route for human infection, confirmed CV-A16 neurotropism and demonstrated squamous epitheliotropism reminiscent of HFMD, attributes not found in other animal models. It should be useful to investigate neuropathogenesis, model person-to-person transmission, and for testing antiviral drugs and vaccines.


Assuntos
Cricetinae/virologia , Modelos Animais de Doenças , Encefalomielite/virologia , Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/virologia , Boca/virologia , Animais , Antígenos Virais/metabolismo , Criança , Encefalomielite/diagnóstico , Enterovirus Humano A/genética , Enterovirus Humano A/metabolismo , Fezes/virologia , Doença de Mão, Pé e Boca/diagnóstico , Humanos , Imuno-Histoquímica , Hibridização In Situ , Boca/patologia , Mucosa Bucal/patologia , Mucosa Bucal/virologia , RNA Viral/genética , Sensibilidade e Especificidade
7.
J Virol ; 92(6)2018 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-29263272

RESUMO

Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) are closely related enteroviruses that cause the same hand, foot, and mouth disease (HFMD), but neurological complications occur only very rarely in CV-A16 compared to EV-A71 infections. To elucidate host responses that may be able to explain these differences, we performed transcriptomic analysis and real-time quantitative PCR (RT-qPCR) in CV-A16-infected neuroblastoma cells (SK-N-SH), and the results showed that the radical S-adenosylmethionine domain containing 2 (RSAD2) was the highest upregulated gene in the antimicrobial pathway. Increased RSAD2 expression was correlated with reduced viral replication, while RSAD2 knockdown cells were correlated with increased replication. EV-A71 replication showed no apparent correlation to RSAD2 expressions. Absent in melanoma 2 (AIM2), which is associated with pyroptotic cell death, was upregulated in EV-A71-infected neurons but not in CV-A16 infection, suggesting that the AIM2 inflammasome played a significant role in suppressing EV-A71 replication. Chimeric viruses derived from CV-A16 and EV-A71 but containing swapped 5' nontranslated regions (5' NTRs) showed that RSAD2 expression/viral replication and AIM2 expression/viral replication patterns may be linked to the 5' NTRs of parental viruses. Differences in secondary structure of internal ribosomal entry sites within the 5' NTR may be responsible for these findings. Overall, our results suggest that CV-A16 and EV-A71 elicit different host responses to infection, which may help explain the apparent lower incidence of CV-A16-associated neurovirulence in HFMD outbreaks compared to EV-A71 infection.IMPORTANCE Although coxsackievirus A16 (CV-A16) and enterovirus A17 (EV-A71) both cause hand, foot, and mouth disease, EV-A71 has emerged as a leading cause of nonpolio, enteroviral fatal encephalomyelitis among young children. The significance of our research is in the identification of the possible differing and novel mechanisms of CV-A16 and EV-A71 inhibition in neuronal cells that may impact viral neuropathogenesis. We further showed that viral 5' NTRs may play significant roles in eliciting different host response mechanisms.


Assuntos
Regiões 5' não Traduzidas , Proteínas de Ligação a DNA/metabolismo , Enterovirus Humano A/fisiologia , Enterovirus Humano C/fisiologia , Neurônios/metabolismo , Proteínas/metabolismo , Replicação Viral/fisiologia , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Técnicas de Silenciamento de Genes , Humanos , Neurônios/patologia , Neurônios/virologia , Oxirredutases atuantes sobre Doadores de Grupo CH-CH , Proteínas/genética
8.
J Med Virol ; 90(6): 1164-1167, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29457642

RESUMO

Enterovirus A71 (EV-A71) neutralization escape mutants were generated with monoclonal antibody MAB979 (Millipore). The VP2-T141I and VP1-D14N substitutions were identified. Using reverse genetics, infectious clones with these substitutions were constructed and tested by neutralization assay with immune sera from mice and humans. The N-terminus VP1-14 is more important than EF loop VP2-141 in acute human infection, mainly because it recognised IgM present in acute infection. The N-terminus VP1 could be a useful target for diagnostics and therapeutic antibodies in acute infection.


Assuntos
Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Proteínas do Capsídeo/imunologia , Enterovirus Humano A/imunologia , Epitopos/imunologia , Adulto , Animais , Proteínas do Capsídeo/genética , Mapeamento de Epitopos , Epitopos/genética , Humanos , Epitopos Imunodominantes/imunologia , Camundongos , Mutação de Sentido Incorreto
9.
Arch Virol ; 162(3): 727-737, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27878462

RESUMO

Enterovirus A71 (EV-A71) and coxsackievirus A16 (CV-A16) are closely related enteroviruses that cause hand, foot and mouth disease (HFMD) in children. Serious neurological complications almost always occur in EV-A71 infection, but are rare in CV-A16 infection. Based on the hypothesis that this may be because EV-A71 infects neuronal cells more easily than CV-A16, we compared virus infection, replication and spread of EV-A71 and CV-A16 in SK-N-SH cells. We found that CV-A16 invariably showed significantly lower replication and caused less necrotic cell death in SK-N-SH cells, compared with EV-A71. This was not due to a lower proportion of CV-A16-infected cells, since both viruses showed similar proportions of infected cells at all time points analyzed. Furthermore, reduced replication of CV-A16 in SK-N-SH cells does not appear to be due to limited viral receptor availability, which might limit viral entry, because experiments with viral RNA-transfected cells showed the same results as for live virus infections. On the other hand, no differences were observed between EV-A71 and CV-A16 in RD cells and results were generally similar in RD cells for both viruses. Taken together, our findings suggest that the poor growth of CV-A16 and EV-A71in SK-N-SH cells, compared with RD cells, may be due to cell type-specific restrictions on viral replication and spread. Furthermore, the lower viral replication and necrotic cell death in CV-A16-infected SK-N-SH cells, compared with EV-A71-infected SK-N-SH cells, is consistent with the lower prevalence of neurotropism observed in CV-A16-associated HFMD outbreaks. Nonetheless, in vivo data and more extensive comparisons of different viral strains are essential to confirm our findings.


Assuntos
Enterovirus Humano A/fisiologia , Doença de Mão, Pé e Boca/virologia , Neurônios/virologia , Linhagem Celular , Replicação do DNA , Enterovirus , Enterovirus Humano A/química , Enterovirus Humano A/classificação , Enterovirus Humano A/crescimento & desenvolvimento , Humanos , Cinética , RNA Viral/genética , RNA Viral/metabolismo , Replicação Viral
10.
Proc Natl Acad Sci U S A ; 110(36): 14753-8, 2013 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-23959904

RESUMO

Enterovirus 71 (EV71) typically causes mild hand-foot-and-mouth disease in children, but it can also cause severe neurological disease. Recently, epidemic outbreaks of EV71 with significant mortality have been reported in the Asia-Pacific region, and EV71 infection has become a serious public health concern worldwide. However, there is little information available concerning EV71 neuropathogenesis, and no vaccines or anti-EV71 drugs have been developed. Previous studies of this disease have used monkeys and neonatal mice that are susceptible to some EV71 strains as models. The monkey model is problematic for ethical and economical reasons, and mice that are more than a few weeks old lose their susceptibility to EV71. Thus, the development of an appropriate small animal model would greatly contribute to the study of this disease. Mice lack EV71 susceptibility due to the absence of a receptor for this virus. Previously, we identified the human scavenger receptor class B, member 2 (hSCARB2) as a cellular receptor for EV71. In the current study, we generated a transgenic (Tg) mouse expressing hSCARB2 with an expression profile similar to that in humans. Tg mice infected with EV71 exhibited ataxia, paralysis, and death. The most severely affected cells were neurons in the spinal cord, brainstem, cerebellum, hypothalamus, thalamus, and cerebrum. The pathological features in these Tg mice were generally similar to those of EV71 encephalomyelitis in humans and experimentally infected monkeys. These results suggest that this Tg mouse could represent a useful animal model for the study of EV71 infection.


Assuntos
Doenças do Sistema Nervoso Central/genética , Modelos Animais de Doenças , Infecções por Enterovirus/genética , Proteínas de Membrana Lisossomal/genética , Receptores Depuradores/genética , Animais , Western Blotting , Encéfalo/metabolismo , Encéfalo/patologia , Encéfalo/virologia , Linhagem Celular Tumoral , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/virologia , Chlorocebus aethiops , Enterovirus Humano A/fisiologia , Infecções por Enterovirus/metabolismo , Infecções por Enterovirus/virologia , Interações Hospedeiro-Patógeno , Humanos , Imuno-Histoquímica , Proteínas de Membrana Lisossomal/metabolismo , Camundongos , Camundongos Transgênicos , Receptores Depuradores/metabolismo , Medula Espinal/metabolismo , Medula Espinal/patologia , Medula Espinal/virologia , Fatores de Tempo , Células Vero
11.
BMC Med ; 13: 226, 2015 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-26381232

RESUMO

BACKGROUND: To investigate the long-term effects on immunity of an inactivated enterovirus 71 (EV71) vaccine and its protective efficacy. METHODS: A sub-cohort of 1,100 volunteers from Guangxi Province in China was eligible for enrolment and randomly administered either the EV71 vaccine or a placebo on days 0 and 28 in a phase III clinical trial and then observed for the following 2 years with approval by an independent ethics committee of Guangxi Zhuang Autonomous Region, China. Serum samples from the 350 participants who provided a full series of blood samples (at all the sampling points) within the 2-year period were collected. Vaccine-induced immune effects, including the neutralizing antibody titres and cross-protection against different genotypes of EV71, were examined. This study also evaluated the protective efficacy of this vaccine based upon clinical diagnosis. RESULTS: This sub-cohort showed a >60% drop-out rate over 2 years. The seroconversion rates among the 161 immunized subjects remained >95% at the end of study. The geometric mean titres of neutralizing antibodies (anti-genotype C4) 360 days after vaccination in 350 subjects were 81.0 (subjects aged 6-11 months), 98.4 (12-23 months), 95.0 (24-35 months), and 81.8 (36-71 months). These titres subsequently increased to 423.1, 659.0, 545.0, and 321.9, respectively, at 540 days post-immunization (d.p.i.), and similar levels were maintained at 720 d.p.i. Higher IFN-γ/IL-4-specific responses to the C4 genotype of EV71 and cross-neutralization reactivity against major EV71 genotype strains were observed in the vaccine group compared to those in the placebo group. Five EV71-infected subjects were observed in the placebo-treated control group and none in the vaccine-immunized group in per-protocol analysis. CONCLUSION: These results are consistent with the induction of dynamic immune responses and protective efficacy of the vaccine against most circulating EV71 strains. TRIAL REGISTRATION NUMBER: Clinicaltrials.gov, NCT01569581, Trial registration date: March 2012.


Assuntos
Infecções por Enterovirus/prevenção & controle , Vacinação , Vacinas de Produtos Inativados/administração & dosagem , Vacinas Virais/administração & dosagem , Anticorpos Antivirais/sangue , Antígenos Virais/imunologia , Pré-Escolar , China , Proteção Cruzada , Método Duplo-Cego , Enterovirus Humano A/imunologia , Feminino , Humanos , Lactente , Masculino , Resultado do Tratamento
12.
Am J Pathol ; 184(3): 714-20, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24378407

RESUMO

Enterovirus 71 (EV71; family Picornaviridae, species human Enterovirus A) usually causes hand, foot, and mouth disease, which may rarely be complicated by fatal encephalomyelitis. We investigated extra-central nervous system (extra-CNS) tissues capable of supporting EV71 infection and replication, and have correlated tissue infection with expression of putative viral entry receptors, scavenger receptor B2 (SCARB2), and P-selectin glycoprotein ligand-1 (PSGL-1). Formalin-fixed, paraffin-embedded CNS and extra-CNS tissues from seven autopsy cases were examined by IHC and in situ hybridization to evaluate viral antigens and RNA. Viral receptors were identified with IHC. In all seven cases, the CNS showed stereotypical distribution of inflammation and neuronal localization of viral antigens and RNA, confirming the clinical diagnosis of EV71 encephalomyelitis. In six cases in which tonsillar tissues were available, viral antigens and/or RNA were localized to squamous epithelium lining the tonsillar crypts. Tissues from the gastrointestinal tract, pancreas, mesenteric nodes, spleen, and skin were all negative for viral antigens/RNA. Our novel findings strongly suggest that tonsillar crypt squamous epithelium supports active viral replication and represents an important source of viral shedding that facilitates person-to-person transmission by both the fecal-oral or oral-oral routes. It may also be a portal for viral entry. A correlation between viral infection and SCARB2 expression appears to be more significant than for PSGL-1 expression.


Assuntos
Encefalomielite/virologia , Enterovirus Humano A/fisiologia , Proteínas de Membrana Lisossomal/metabolismo , Glicoproteínas de Membrana/metabolismo , Tonsila Palatina/virologia , Receptores Depuradores/metabolismo , Replicação Viral , Adolescente , Adulto , Sistema Nervoso Central/virologia , Criança , Epitélio/virologia , Humanos , Inflamação , Masculino , Boca , RNA Viral/genética , Receptores Virais/metabolismo , Adulto Jovem
13.
Mod Pathol ; 27(5): 657-64, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24186135

RESUMO

Burkholderia pseudomallei causes a potentially fatal infection called melioidosis. We have developed a nonfluorescent, colorimetric in situ hybridization assay using a specific probe to target 16s rRNA of B. pseudomallei in formalin-fixed, paraffin-embedded infected tissues for diagnostic purposes and to study infectious disease pathology. A 63-base pair DNA probe was synthesized and labeled with digoxigenin by PCR. Probe specificity was confirmed by BLAST analysis and by testing on appropriate microbial controls. The in situ hybridization assay was specifically and consistently positive for B. pseudomallei, showing strongly and crisply stained, single bacillus and bacilli clusters in mainly inflamed tissues in seven human acute melioidosis cases and experimentally infected mouse tissues. Intravascular and extravascular bacilli were detected in both intracellular and extracellular locations in various human organs, including lung, spleen, kidney, liver, bone marrow, and aortic mycotic aneurysm, particularly in the inflamed areas. Intravascular, intracellular bacteria in melioidosis have not been previously reported. Although the identity of infected intravascular leukocytes has to be confirmed, extravascular, intracellular bacilli appear to be found mainly within macrophages and neutrophils. Rarely, large intravascular, extracellular bacillary clusters/emboli could be detected in both human and mouse tissues. B. cepacia and non-Burkholderia pathogens (16 microbial species) all tested negative. Nonpathogenic B. thailandensis showed some cross-hybridization but signals were less intense. This in situ hybridization assay could be usefully adapted for B. pseudomallei identification in other clinical specimens such as pus and sputum.


Assuntos
Burkholderia pseudomallei/isolamento & purificação , Melioidose/diagnóstico , Animais , Humanos , Hibridização In Situ , Melioidose/patologia , Camundongos , Sensibilidade e Especificidade
14.
J Infect Dis ; 207(3): 469-78, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23175762

RESUMO

Nipah virus (NiV) and Hendra virus (HeV) are closely related, recently emerged paramyxoviruses that are capable of causing considerable morbidity and mortality in several mammalian species, including humans. Henipavirus-specific vaccines are still commercially unavailable, and development of novel antiviral strategies to prevent lethal infections due to henipaviruses is highly desirable. Here we describe the development of adeno-associated virus (AAV) vaccines expressing the NiV G protein. Characterization of these vaccines in mice demonstrated that a single intramuscular AAV injection was sufficient to induce a potent and long-lasting antibody response. Translational studies in hamsters further demonstrated that all vaccinated animals were protected against lethal challenge with NiV. In addition, this vaccine induced a cross-protective immune response that was able to protect 50% of the animals against a challenge by HeV. This study presents a new efficient vaccination strategy against henipaviruses and opens novel perspectives on the use of AAV vectors as vaccines against emergent diseases.


Assuntos
Dependovirus/genética , Vetores Genéticos/genética , Infecções por Henipavirus/imunologia , Infecções por Henipavirus/prevenção & controle , Vacinas Sintéticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Linhagem Celular Tumoral , Cricetinae , Modelos Animais de Doenças , Infecções por Henipavirus/virologia , Humanos , Imunidade Humoral , Imunoglobulina G/imunologia , Masculino , Camundongos , Vacinas Sintéticas/genética , Vacinas Virais/genética
15.
Electrophoresis ; 34(17): 2495-502, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23784731

RESUMO

Confirmation of oral squamous cell cancer (OSCC) currently relies on histological analysis, which does not provide clear indication of cancer development from precancerous lesions. In the present study, whole saliva proteins of patients with OSCC (n = 12) and healthy subjects (n = 12) were separated by 2DE to identify potential candidate biomarkers that are much needed to improve detection of the cancer. The OSCC patients' 2DE saliva protein profiles appeared unique and different from those obtained from the healthy subjects. The patients' saliva α1-antitrypsin (AAT) and haptoglobin (HAP) ß chains were resolved into polypeptide spots with increased microheterogeneity, although these were not apparent in their sera. Their 2DE protein profiles also showed presence of hemopexin and α-1B glycoprotein, which were not detected in the profiles of the control saliva. When subjected to densitometry analysis, significant altered levels of AAT, complement C3, transferrin, transthyretin, and ß chains of fibrinogen and HAP were detected. The increased levels of saliva AAT, HAP, complement C3, hemopexin, and transthyretin in the OSCC patients were validated by ELISA. The strong association of AAT and HAP with OSCC was further supported by immunohistochemical staining of cancer tissues. The differently expressed saliva proteins may be useful complementary biomarkers for the early detection and/or monitoring of OSCC, although this requires validation in clinically representative populations.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Bucais/metabolismo , Saliva/metabolismo , Proteínas e Peptídeos Salivares/metabolismo , Adulto , Idoso , Biomarcadores Tumorais/química , Carcinoma de Células Escamosas/química , Eletroforese em Gel Bidimensional , Ensaio de Imunoadsorção Enzimática , Haptoglobinas/química , Haptoglobinas/metabolismo , Humanos , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Pessoa de Meia-Idade , Neoplasias Bucais/química , Proteômica/métodos , Proteínas e Peptídeos Salivares/química , Língua/química , Língua/metabolismo , Língua/patologia , alfa 1-Antitripsina/química , alfa 1-Antitripsina/metabolismo
16.
BMC Complement Altern Med ; 13: 192, 2013 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-23889893

RESUMO

BACKGROUND: The absence of commercialized vaccines and antiviral agents against dengue has made the disease a major health concern around the world. With the current dengue virus transmission rate and incidences, the development of antiviral drugs is of vital need. The aim of this project was to evaluate the possibility of developing a local medicinal plant, Phyllanthus as an anti-dengue agent. METHODS: Cocktail (aqueous and methanolic) extracts were prepared from four species of Phyllanthus (P.amarus, P.niruri, P.urinaria, and P.watsonii) and their polyphenolic compounds were identified via HPLC and LC-MS/MS analysis. MTS assay was then carried out to determine the maximal non-toxic dose (MNTD) of the extracts, followed by screening of the in vitro antiviral activity of aqueous cocktail extracts against DENV2 by means of time-of-addition (pre-, simultaneous and post-) using RT-qPCR. The differentially expressed proteins in the treated and infected cells were analysed with two dimensional gel electrophoresis experiments. RESULTS: Several active compounds including gallic acid, geraniin, syringin, and corilagen have been identified. The MNTD of both aqueous and methanolic extracts on Vero cells were 250.0 µg/ml and 15.63 µg/ml respectively. Phyllanthus showed strongest inhibitory activity against DENV2 with more than 90% of virus reduction in simultaneous treatment. Two-dimensional analysis revealed significantly altered levels of thirteen proteins, which were successfully identified by tandem MS (MS/MS). These altered proteins were involved in several biological processes, including viral entry, viral transcription and translation regulations, cytoskeletal assembly, and cellular metabolisms. CONCLUSIONS: Phyllanthus could be potentially developed as an anti-DENV agent.


Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Dengue/virologia , Phyllanthus/química , Extratos Vegetais/farmacologia , Animais , Chlorocebus aethiops , Ácido Gálico/farmacologia , Glucosídeos/farmacologia , Humanos , Taninos Hidrolisáveis/farmacologia , Fenilpropionatos/farmacologia , Plantas Medicinais , Espectrometria de Massas em Tandem , Células Vero
17.
Arch Physiol Biochem ; 129(1): 186-197, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32813560

RESUMO

AIM: A high-fat diet (HFD) can lead to obesity and related metabolic disorders. This study evaluated the preventive efficacy of myricetin derivative-rich fraction (MD) from Syzygium malaccense leaf extract against HFD-induced obesity, hyperglycaemia, and oxidative stress in C57BL/6J mice. METHODS: HFD-fed mice were administered MD (50 mg/kg, 100 mg/kg, and 150 mg/kg) or 2 mg/kg metformin (positive control) orally for 16 weeks. Normal diet and HFD-fed control groups received normal saline. RESULTS: MD dose of 50 mg/kg was better than 100 mg/kg and 150 mg/kg in significantly reducing weight-gain, glucose intolerance, insulin resistance, lipid accumulation in liver and kidney, and improving the serum lipid profile. Lowered protein carbonyls and lipid hydroperoxides in urine and tissue homogenates and elevated reduced glutathione, ferric reducing antioxidant power (FRAP), and Trolox equivalent antioxidant capacity (TEAC) levels in tissue homogenates indicated amelioration of oxidative stress. CONCLUSION: MD has therapeutic value in the prevention and management of obesity, hyperglycaemia, and oxidative stress.


Assuntos
Intolerância à Glucose , Resistência à Insulina , Syzygium , Camundongos , Animais , Intolerância à Glucose/etiologia , Intolerância à Glucose/prevenção & controle , Antioxidantes/metabolismo , Dieta Hiperlipídica/efeitos adversos , Syzygium/metabolismo , Camundongos Endogâmicos C57BL , Obesidade/etiologia , Obesidade/prevenção & controle , Obesidade/tratamento farmacológico , Estresse Oxidativo , Lipídeos
18.
Int J Med Mushrooms ; 25(4): 27-42, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075082

RESUMO

Ganoderma neo-japonicum Imazeki is a medicinal mushroom consumed by the indigenous people in Malaysia as a remedy for diabetes. This study aims to validate the efficacy of G. neo-japonicum polysaccharides (GNJP) on obesity-induced type 2 diabetes mellitus (T2DM) in C57BL/6J mice. Mice were divided into seven groups; normal diet (ND)-control, high-fat-diet (HFD)-control, HFDGNJP-treated (50, 100, 200 mg/kg b.w.), HFDMET (metformin 50 mg/kg; positive-control) and ND-GNJP (200 mg/kg b.w.). Mice were administered GNJP or metformin orally for 10 weeks (thrice/week) and sacrificed after an oral glucose tolerance test. Body weight, serum biochemicals, liver histology, adipocyte gene expressions, glucose and insulin levels were measured. HFD caused obesity, dyslipidemia, and diabetes in the untreated groups. GNJP (50 mg/kg b.w.) supplementation prevented weight gain and liver steatosis, improved serum lipid profile and glucose tolerance and attenuated hyperglycemia and hyperinsulinemia more effectively when compared with the other treatment groups. The prevention of obesity and lipid dysregulation is plausibly attributed to the increased hormone-sensitive lipase and reduced Akt-1 and Ppary gene expressions while the up-regulation of AdipoQ (adiponectin), Prkag2 and Slc2a4 genes served to sensitize insulin and improve glucose uptake. Thus, supplementation with an appropriate dose of GNJP has promising efficacies in preventing HFD aka obesity-induced T2DM and associated metabolic abnormalities.


Assuntos
Agaricales , Basidiomycota , Diabetes Mellitus Tipo 2 , Resistência à Insulina , Metformina , Animais , Camundongos , Diabetes Mellitus Tipo 2/prevenção & controle , Agaricales/metabolismo , Camundongos Endogâmicos C57BL , Glicemia/metabolismo , Obesidade/complicações , Obesidade/prevenção & controle , Insulina/metabolismo , Polissacarídeos , Dieta Hiperlipídica/efeitos adversos , Metformina/uso terapêutico , Basidiomycota/metabolismo , Lipídeos
19.
Virol J ; 9: 155, 2012 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-22877087

RESUMO

Enterovirus 71 (EV71) causes severe neurological diseases resulting in high mortality in young children worldwide. Development of an effective vaccine against EV71 infection is hampered by the lack of appropriate animal models for efficacy testing of candidate vaccines. Previously, we have successfully tested the immunogenicity and protectiveness of a candidate EV71 vaccine, containing recombinant Newcastle disease virus capsids that display an EV71 VP1 fragment (NPt-VP11-100) protein, in a mouse model of EV71 infection. A drawback of this system is its limited window of EV71 susceptibility period, 2 weeks after birth, leading to restricted options in the evaluation of optimal dosing regimens. To address this issue, we have assessed the NPt-VP11-100 candidate vaccine in a hamster system, which offers a 4-week susceptibility period to EV71 infection. Results obtained showed that the NPt-VP11-100 candidate vaccine stimulated excellent humoral immune response in the hamsters. Despite the high level of antibody production, they failed to neutralize EV71 viruses or protect vaccinated hamsters in viral challenge studies. Nevertheless, these findings have contributed towards a better understanding of the NPt-VP11-100 recombinant protein as a candidate vaccine in an alternative animal model system.


Assuntos
Anticorpos Antivirais/sangue , Proteínas do Capsídeo/imunologia , Enterovirus Humano A/imunologia , Imunização/métodos , Vacinas Virais/imunologia , Animais , Anticorpos Neutralizantes/sangue , Proteínas do Capsídeo/administração & dosagem , Cricetinae , Modelos Animais de Doenças , Infecções por Enterovirus/prevenção & controle , Mesocricetus , Vacinas Sintéticas/administração & dosagem , Vacinas Sintéticas/imunologia , Vacinas Virais/administração & dosagem
20.
J Virol ; 84(1): 661-5, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19864378

RESUMO

Enterovirus 71 (EV71) causes childhood hand, foot, and mouth disease and neurological complications, and no vaccines or therapeutic drugs are currently available. Formaldehyde-inactivated whole-virus vaccines derived from EV71 clinical isolates and a mouse-adapted virus (MAV) were tested in a mouse model of EV71 encephalomyelitis. After only two immunizations, given to mice at 1 and 7 days of age, the MAV vaccine protected mice at 14 days of age from disease. Tissues from immunized mice were negative for virus by viral culture, reverse transcriptase PCR, immunohistochemistry analysis, and in situ hybridization. Cross-neutralizing EV71 antibodies to strains with genotypes B3, B4, and C1 to C5 generated in immunized adult mice were able to passively protect 14-day-old mice from disease.


Assuntos
Encefalomielite/prevenção & controle , Infecções por Enterovirus/prevenção & controle , Enterovirus , Vacinas de Produtos Inativados/farmacologia , Animais , Anticorpos Neutralizantes/imunologia , Proteção Cruzada , Modelos Animais de Doenças , Formaldeído/farmacologia , Genótipo , Humanos , Imunização , Camundongos , Vacinas de Produtos Inativados/uso terapêutico
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