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1.
Nat Commun ; 12(1): 5298, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489428

RESUMO

Ferroelectricity, the electrostatic counterpart to ferromagnetism, has long been thought to be incompatible with metallicity due to screening of electric dipoles and external electric fields by itinerant charges. Recent measurements, however, demonstrated signatures of ferroelectric switching in the electrical conductance of bilayers and trilayers of WTe2, a semimetallic transition metal dichalcogenide with broken inversion symmetry. An especially promising aspect of this system is that the density of electrons and holes can be continuously tuned by an external gate voltage. This degree of freedom enables measurement of the spontaneous polarization as free carriers are added to the system. Here we employ capacitive sensing in dual-gated mesoscopic devices of bilayer WTe2 to directly measure the spontaneous polarization in the metallic state and quantify the effect of free carriers on the polarization in the conduction and valence bands, separately. We compare our results to a low-energy model for the electronic bands and identify the layer-polarized states that contribute to transport and polarization simultaneously. Bilayer WTe2 is thus shown to be a fully tunable ferroelectric metal and an ideal platform for exploring polar ordering, ferroelectric transitions, and applications in the presence of free carriers.

2.
Anat Histol Embryol ; 49(4): 440-450, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32128873

RESUMO

The present study was conducted to evaluate the effect of histamine and to characterise its receptor subtypes in reticular groove (RG) smooth muscle of adult goats. The studies were done using floor and lip regions of RG. We used tension experiments on smooth muscle of RG isolated from adult goat for functional characterisation of H1 and H2 receptors. Western blotting and immunohistochemistry experiments were conducted for molecular characterisation of these receptors. Histamine evoked concentration-dependent contraction of isolated RG circular and longitudinal smooth muscle preparation. Pyrilamine antagonised the action of histamine. Histamine did not induce any relaxant effect on RG preparations. Additionally, cimetidine did not produce any significant effect on histamine-induced response. Non-selective histaminic receptor antagonist cyproheptadine attenuated the contraction response to histamine in the smooth muscle. Molecular characterisation and localisation of H1 and H2 receptor proteins confirmed the presence of these receptors in RG. It is most likely that histamine-induced contractile effect in RG smooth muscle of goats is mediated by H1 histaminic receptors.


Assuntos
Cabras/metabolismo , Histamina/metabolismo , Músculo Liso/fisiologia , Receptores Histamínicos/fisiologia , Estômago de Ruminante/fisiologia , Animais , Western Blotting , Cimetidina/farmacologia , Ciproeptadina/farmacologia , Relação Dose-Resposta a Droga , Cabras/anatomia & histologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Antagonistas dos Receptores H2 da Histamina/farmacologia , Imuno-Histoquímica , Contração Muscular/efeitos dos fármacos , Contração Muscular/fisiologia , Pirilamina/farmacologia , Receptores Histamínicos/classificação , Estômago de Ruminante/anatomia & histologia
3.
Sci Rep ; 10(1): 2164, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-32034180

RESUMO

Transplacental transmission (TPT) of wild-type Indian BTV-1 had never been experimentally proved. This study was first time investigated TPT of Indian BTV-1 (isolated from aborted and stillborn goat fetal spleens). The sequential pathology, virological and immune cell kinetics (CD4+, CD8+ T-lymphocytes and NK cells in spleen and PBMCs), and apoptosis in IFNAR1-blocked pregnant mice during early (infected on 1 GD) and mid (infected on 8 GD) gestation have been studied. There was higher rate of TPT during mid stage (71.43%) than early (57.14%) stage. In early stage reduced implantation sites, early embryonic deaths, abortions, and necro-haemorrhagic lesions had observed. Mid stage, congenital defects and neurological lesions in foetuses like haemorrhages, diffuse cerebral edema, necrotizing encephalitis and decreased bone size (Alizarin red staining) were noticed. BTV-1 antigen was first time demonstrable in cells of mesometrium, decidua of embryos, placenta, uterus, ovary, and brain of foetuses by immunohistochemistry and quantified by real-time qRT-PCR. BTV-inoculated mice were seroconverted by 7 and 5 dpi, and reached peak levels by 15 and 9 dpi in early and mid gestation, respectively. CD4+ and CD8+ cells were significantly decreased (increased ratio) on 7 dpi but subsequently increased on 15 dpi in early gestation. In mid gestation, increased CD8+ cells (decreased ratio) were observed. Apoptotic cells in PBMCs and tissues increased during peak viral load. This first time TPT of wild-type Indian BTV-1 deserves to be reported for implementation of control strategies. This model will be very suitable for further research into mechanisms of TPT, overwintering, and vaccination strategies.


Assuntos
Bluetongue/patologia , Doenças Fetais/imunologia , Doenças Fetais/patologia , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez/patologia , Receptor de Interferon alfa e beta/deficiência , Animais , Antígenos Virais/imunologia , Bluetongue/imunologia , Bluetongue/transmissão , Bluetongue/virologia , Vírus Bluetongue/imunologia , Vírus Bluetongue/patogenicidade , Osso e Ossos/anormalidades , Encéfalo/anormalidades , Feminino , Doenças Fetais/virologia , Camundongos , Gravidez , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/virologia , Receptor de Interferon alfa e beta/genética , Baço/imunologia , Linfócitos T/imunologia
4.
Gene ; 515(2): 385-90, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23266630

RESUMO

MicroRNAs are short non-coding RNAs that can regulate gene expression during various crucial cell processes such as differentiation, proliferation and apoptosis. Changes in expression profiles of miRNA play an important role in the development of many cancers, including CRC. Therefore, the identification of cancer related miRNAs and their target genes are important for cancer biology research. In this paper, we applied TSK-type recurrent neural fuzzy network (TRNFN) to infer miRNA-mRNA association network from paired miRNA, mRNA expression profiles of CRC patients. We demonstrated that the method we proposed achieved good performance in recovering known experimentally verified miRNA-mRNA associations. Moreover, our approach proved successful in identifying 17 validated cancer miRNAs which are directly involved in the CRC related pathways. Targeting such miRNAs may help not only to prevent the recurrence of disease but also to control the growth of advanced metastatic tumors. Our regulatory modules provide valuable insights into the pathogenesis of cancer.


Assuntos
Neoplasias Colorretais/genética , Simulação por Computador , Lógica Fuzzy , MicroRNAs/genética , Redes Neurais de Computação , RNA Mensageiro/genética , Algoritmos , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Humanos , Modelos Genéticos , Interferência de RNA
5.
Gene ; 506(2): 408-16, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22759510

RESUMO

In this work we applied a TSK-type recurrent neural fuzzy approach to extract regulatory relationship among genes and reconstruct gene regulatory network from microarray data. The identified signature has captured the regulatory relationship among 27 differentially expressed genes from microarray dataset. We applied three different methods viz., feed forward neural fuzzy, modified genetic algorithm and recurrent neural fuzzy, on the same data set for the inference of GRNs and the results obtained are almost comparable. In all tested cases, TRNFN identified more biologically meaningful relations. We found that 87.8% of the total interactions extracted by TRNFN are correct in accordance with the biological knowledge. Our analysis resulted in 2 major outcomes. First, upregulated genes are regulated by more genes than downregulated genes. Second, tumor activators activate other tumor activators and suppress tumor suppressers strongly in the disease environment. These findings will help to elucidate the common molecular mechanism of colon cancer, and provide new insights into cancer diagnostics, prognostics and therapy.


Assuntos
Neoplasias do Colo/genética , Biologia Computacional/métodos , Redes Reguladoras de Genes , Análise de Sequência com Séries de Oligonucleotídeos , Algoritmos , Neoplasias do Colo/metabolismo , Lógica Fuzzy , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Modelos Estatísticos , Neoplasias/metabolismo , Redes Neurais de Computação , Saccharomyces cerevisiae/metabolismo
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