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2.
BMC Psychiatry ; 22(1): 597, 2022 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-36076225

RESUMO

BACKGROUND: Borna disease virus 1 (BoDV-1) is a non-segmented, negative-strand RNA virus that persistently infects mammals including humans. BoDV-1 worldwide occurring strains display highly conserved genomes with overlapping genetic signatures between those of either human or animal origin. BoDV-1 infection may cause behavioral and cognitive disturbances in animals but has also been found in human major depression and obsessive-compulsive disorder (OCD). However, the impact of BoDV-1 on memory functions in OCD is unknown. METHOD: To evaluate the cognitive impact of BoDV-1 in OCD, event-related brain potentials (ERPs) were recorded in a continuous word recognition paradigm in OCD patients (n = 16) and in healthy controls (n = 12). According to the presence of BoDV-1-specific circulating immune complexes (CIC), they were divided into two groups, namely group H (high) and L (low), n = 8 each. Typically, ERPs to repeated items are characterized by more positive waveforms beginning approximately 250 ms post-stimulus. This "old/new effect" has been shown to be relevant for memory processing. The early old/new effect (ca. 300-500 ms) with a frontal distribution is proposed to be a neural correlate of familiarity-based recognition. The late old/new effect (post-500 ms) is supposed to reflect memory recollection processes. RESULTS: OCD patients were reported to show a normal early old/new effect and a reduced late old/new effect compared to normal controls. In our study, OCD patients with a high virus load (group H) displayed exactly these effects, while patients with a low virus load (group L) did not differ from healthy controls. CONCLUSION: These results confirmed that OCD patients had impaired memory recollection processes compared to the normal controls which may to some extent be related to their BoDV-1 infection.


Assuntos
Doença de Borna , Vírus da Doença de Borna , Transtorno Obsessivo-Compulsivo , Animais , Complexo Antígeno-Anticorpo , Vírus da Doença de Borna/genética , Potenciais Evocados , Humanos , Mamíferos , Reconhecimento Psicológico
3.
Front Cell Infect Microbiol ; 11: 681937, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34447698

RESUMO

Dengue virus (DENV) infection is prevalent in tropical and subtropical regions of the world, which is fatal if untreated symptomatically. Emergence of new genotype within serotypes led to enhanced severity. The objective of the study is to identify the molecular characteristics of the DENV circulated during 2017 outbreak in Tamil Nadu, India, and to investigate the role of inflammatory cytokines in different "serotypes" and in "dengue severity". A total of 135 suspected samples were tested for DENV infection using IgM, IgG, and qPCR assay; where 76 samples were positive for DENV and analyzed for 12 inflammatory cytokines using ELISA. Serotyping shows 14 DENV-1, 22 DENV-2, 7 DENV-3, and 33 DENV-4, where DENV-4 was predominant. Among 76, 42 isolates were successfully sequenced for C-prM region and grouped. A lineage shift was observed in DENV-4 genotype. Irrespective of serotypes, IFNγ was significantly elevated in all serotypes than control as well as in primary infection than secondary, indicating its role in immune response. GM-CSF and IP-10 were significantly elevated in secondary infection and could be used as prognostic biomarkers for secondary infection. Our observation shows differential cytokine expression profile varied with each serotype, indicating serotype/genotype-specific viral proteins might play a major role in dengue severity. DENV-4 as dominant serotype was reported in Tamil Nadu for the first time during an outbreak with a mixed Th1/Th17 cytokine expression profile that correlated with disease severity. We conclude it is essential to identify circulating viral genotype and their fitness by mutational analysis to correlate with disease severity and immune status, as this correlation will be helpful in diagnostics and therapeutics applications.


Assuntos
Vírus da Dengue , Dengue , Citocinas , Dengue/epidemiologia , Vírus da Dengue/genética , Surtos de Doenças , Genótipo , Humanos , Índia/epidemiologia , Filogenia , Sorogrupo
4.
Hum Immunol ; 82(6): 438-445, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33766427

RESUMO

Dengue virus (DENV) infection is mostly prevalent in tropical and sub-tropical regions of the world. Though most DENV infections are self-limiting febrile like-illness, a small proportion of secondary infection is fatal, if untreated symptomatically. Among various factors involved in severe dengue, immune enhancement by cytokine is the major one. The objective of the study is to elucidate serum cytokine expression among primary and secondary infection and determine if any signature cytokine is correlated with disease severity. Seventy-six serum samples at acute time points were collected during the 2017 DENV outbreak in Madurai, Tamil Nadu. Among the 76 serum samples, 49 belong to primary and 27 to secondary DENV infection. Interestingly, a large number of primary infection presented with DHF/DSS symptoms and, children were found prone to DHF and DSS in secondary infection. The serum samples were analysed for inflammatory cytokines, namely IL-1ß, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-17A, IFN-γ, TNF-α, IP-10 and GM-CSF using ELISA assay as well as mRNA analysis using qPCR. Among the 12 inflammatory cytokines analysed IP-10 and GMCSF mRNA and protein shows significant upregulation in secondary infection. Similarly, a strong correlation was observed between GM-CSF and IP-10 with thrombocytopenia, ascites, serous effusion and spontaneous bleeding. Based on the observations, GM-CSF and IP-10 could be a potential prognostic biomarkers for secondary DENV infection.


Assuntos
Biomarcadores/sangue , Quimiocina CXCL10/sangue , Vírus da Dengue/fisiologia , Dengue/imunologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/sangue , Adolescente , Adulto , Idoso , Criança , Dengue/diagnóstico , Surtos de Doenças , Progressão da Doença , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Prognóstico , Índice de Gravidade de Doença , Trombocitopenia , Adulto Jovem
5.
Front Cell Dev Biol ; 8: 586158, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330463

RESUMO

MicroRNAs regulate gene expression at post-transcriptional levels. Some of them appear to regulate brain development and are involved in neurodevelopmental disorders. This has led to the suggestion that the role of microRNAs in neuronal development and function may be more central than previously appreciated. Here, we review the data about miR-9 function to depict the subtlety, complexity, flexibility and limited functional conservation of this essential developmental regulatory system. On this basis we propose that species-specific actions of miR-9 could underlie to a large degree species differences in brain size, shape and function.

6.
Virus Res ; 260: 142-150, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30508603

RESUMO

Dengue fever is the most prevalent arthropod-borne viral disease, and no specific therapeutic or promising antiviral drug is available for its treatment. Peptide inhibitors are less toxic than synthetic compounds and have found proven effective against viral infections. Here, three peptides that mimic part of the E protein of the dengue virus (DENV) were synthesized and evaluated for their inhibitory activity against four serotypes of DENV in African green monkey kidney (Vero) and rhesus macaque (Macaca mulatta) monkey kidney (LLC-MK2) cell lines. The three peptides, Pep1, Pep2, and Pep3 are located in domains I, II, and III of the E protein respectively. All three peptides effectively reduced >80% of focus forming units in the virus treated mammalian cell lines than control and exhibited their IC50 in the range of 10-33 µM. Pep1 was found effective against DENV-2, DENV-3, and DENV-4 (IC80 below 50 µM). Pep2 showed the highest inhibitory activity against all four serotypes (IC50 below 20 µM). Pep3 reduced the 80% focus forming units in all serotypes at the concentration of 40 µM. Evaluation of peptides at different time points of viral infection in the mammalian cell lines revealed that the peptides inhibited viral infection by binding to the virus and not by binding to cellular receptors and blocking viral entry. The peptides assumedly exert their inhibitory effects by binding to the E protein and repressing its conformational changes; this prevents the virus from binding to cellular receptors, thereby inhibiting viral entry. Hence, these peptides might limit viral spread and reduce the virus's ability to infect.


Assuntos
Antivirais/farmacologia , Vírus da Dengue/efeitos dos fármacos , Vírus da Dengue/fisiologia , Oligopeptídeos/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/síntese química , Linhagem Celular , Chlorocebus aethiops , Concentração Inibidora 50 , Macaca mulatta , Testes de Sensibilidade Microbiana , Oligopeptídeos/síntese química
7.
Sci Rep ; 8(1): 10720, 2018 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-30013072

RESUMO

Macrofungi belonging to the phylum Basidiomycota are mostly used as medicinal mushrooms in many countries. In the present study, hundred basidiocarp of macrofungi were collected from Tamilnadu during rainy season. The basidiocarp was found in association with root/trunk of living trees, wood log and decayed matter. Among the hundred basidiocarp, 49 were grown into axenic cultures. Notable variations in the macroscopic characteristics of the basidiome and culture morphology were observed. To study the genetic diversity, the molecular taxonomy of the isolates was carried out using internal transcribed spacer (ITS) and 5.8S rRNA gene sequence marker. Thirty-two strains belonging to the order Polyporales, Hymenochataeles and Russuales under the division Basidiomycota were classified based on phylogeny analysis. This study provides first evidence for the occurrence of species Fulvifomes fastuosus (LDCMY39 and LDCMY43) and Ganoderma wiiroense (LDCMY02, LDCMY08, LDCMY11, LDCMY17 and LDCMY19) from southern India. Molecular evidence for the existence of Phellinus badius was given for the first time as well. These data enhance our understanding on the diversity of macrofungi in India, which could be further exploited for biomedical applications.


Assuntos
Basidiomycota/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Filogenia , RNA Ribossômico 5,8S/genética , Variação Genética , Índia , Análise de Sequência de DNA
8.
BMC Dev Biol ; 18(1): 3, 2018 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-29471810

RESUMO

BACKGROUND: MiR-9 is a small non-coding RNA that is highly conserved between species and primarily expressed in the central nervous system (CNS). It is known to influence proliferation and neuronal differentiation in the brain and spinal cord of different vertebrates. Different studies have pointed to regional and species-specific differences in the response of neural progenitors to miR-9. METHODS: In ovo and ex ovo electroporation was used to overexpress or reduce miR-9 followed by mRNA in situ hybridisation and immunofluorescent stainings to evaluate miR- expression and the effect of changed miR-9 expression. RESULTS: We have investigated the expression and function of miR-9 during early development of the mid-hindbrain region (MH) in chick. Our analysis reveals a closer relationship of chick miR-9 to mammalian miR-9 than to fish and a dynamic expression pattern in the chick neural tube. Early in development, miR-9 is diffusely expressed in the entire brain, bar the forebrain, and it becomes more restricted to specific areas of the CNS at later stages. MiR-9 overexpression at HH9-10 results in a reduction of FGF8 expression and premature neuronal differentiation in the mid-hindbrain boundary (MHB). Within the midbrain miR-9 does not cause premature neuronal differentiation it rather reduces proliferation in the midbrain. CONCLUSION: Our findings indicate that miR-9 has regional specific effects in the developing mid-hindbrain region with a divergence of response of regional progenitors.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , MicroRNAs/genética , Rombencéfalo/embriologia , Rombencéfalo/metabolismo , Animais , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Divisão Celular/genética , Embrião de Galinha , Sequência Conservada/genética , Regulação para Baixo/genética , Evolução Molecular , Mesencéfalo/citologia , Mesencéfalo/embriologia , Mesencéfalo/metabolismo , MicroRNAs/metabolismo , Tubo Neural/embriologia , Tubo Neural/metabolismo , Neurogênese/genética , Células-Tronco/citologia , Células-Tronco/metabolismo
9.
J Exp Neurosci ; 10: 101-120, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27721656

RESUMO

MicroRNAs (miRNAs) are a class of small regulatory RNAs involved in gene regulation. The regulation is effected by either translational inhibition or transcriptional silencing. In vertebrates, the importance of miRNA in development was discovered from mice and zebrafish dicer knockouts. The miRNA-9 (miR-9) is one of the most highly expressed miRNAs in the early and adult vertebrate brain. It has diverse functions within the developing vertebrate brain. In this article, the role of miR-9 in the developing forebrain (telencephalon and diencephalon), midbrain, hindbrain, and spinal cord of vertebrate species is highlighted. In the forebrain, miR-9 is necessary for the proper development of dorsoventral telencephalon by targeting marker genes expressed in the telencephalon. It regulates proliferation in telencephalon by regulating Foxg1, Pax6, Gsh2, and Meis2 genes. The feedback loop regulation between miR-9 and Nr2e1/Tlx helps in neuronal migration and differentiation. Targeting Foxp1 and Foxp2, and Map1b by miR-9 regulates the radial migration of neurons and axonal development. In the organizers, miR-9 is inversely regulated by hairy1 and Fgf8 to maintain zona limitans interthalamica and midbrain-hindbrain boundary (MHB). It maintains the MHB by inhibiting Fgf signaling genes and is involved in the neurogenesis of the midbrain-hindbrain by regulating Her genes. In the hindbrain, miR-9 modulates progenitor proliferation and differentiation by regulating Her genes and Elav3. In the spinal cord, miR-9 modulates the regulation of Foxp1 and Onecut1 for motor neuron development. In the forebrain, midbrain, and hindbrain, miR-9 is necessary for proper neuronal progenitor maintenance, neurogenesis, and differentiation. In vertebrate brain development, miR-9 is involved in regulating several region-specific genes in a spatiotemporal pattern.

10.
J Cell Mol Med ; 16(11): 2592-610, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22863662

RESUMO

Transplantation is common in clinical practice where there is availability of the tissue and organ. In the case of neurodegenerative disease such as Parkinson's disease (PD), transplantation is not possible as a result of the non-availability of tissue or organ and therefore, cell therapy is an innovation in clinical practice. However, the availability of neuronal cells for transplantation is very limited. Alternatively, immortalized neuronal progenitors could be used in treating PD. The neuronal progenitor cells can be differentiated into dopaminergic phenotype. Here in this article, the current understanding of the molecular mechanisms involved in the differentiation of dopaminergic phenotype from the neuronal progenitors immortalized with SV40 LT antigen is discussed. In addition, the methods of generating dopaminergic neurons from progenitor cells and the factors that govern their differentiation are elaborated. Recent advances in cell-therapy based transplantation in PD patients and future prospects are discussed.


Assuntos
Antígenos Transformantes de Poliomavirus/metabolismo , Diferenciação Celular/fisiologia , Transplante de Células/métodos , Neurônios Dopaminérgicos/citologia , Animais , Antígenos Transformantes de Poliomavirus/genética , Técnicas de Cultura de Células , Linhagem Celular Transformada , Transformação Celular Viral , Vetores Genéticos , Humanos , Doença de Parkinson/patologia , Doença de Parkinson/terapia
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