Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 5 de 5
Filtrar
1.
Phys Rev Lett ; 129(15): 156401, 2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36269973

RESUMO

Chiral materials have attracted significant research interests as they exhibit intriguing physical properties, such as chiral optical response, spin-momentum locking, and chiral induced spin selectivity. Recently, layered transition metal dichalcogenide 1T-TaS_{2} has been found to host a chiral charge density wave (CDW) order. Nevertheless, the physical consequences of the chiral order, for example, in electronic structures and the optical properties, are yet to be explored. Here, we report the spectroscopic visualization of an emergent chiral electronic band structure in the CDW phase, characterized by windmill-shaped Fermi surfaces. We uncover a remarkable chirality-dependent circularly polarized Raman response due to the salient in-plane chiral symmetry of CDW, although the ordinary circular dichroism vanishes. Chiral Fermi surfaces and anomalous Raman responses coincide with the CDW transition, proving their lattice origin. Our Letter paves a path to manipulate the chiral electronic and optical properties in two-dimensional materials and explore applications in polarization optics and spintronics.

2.
Gene Ther ; 16(7): 840-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19440222

RESUMO

To study the effects of excision repair cross-complementing 1 (ERCC1) on the pathophysiological process of brain ischemia, we examined the changes in ERCC1 expression, as well as the functional significance of ERCC1 in the rat brain following middle cerebral artery occlusion (MCAO). The results were as follows: (1) ERCC1 immunopositive cells were widely distributed in various brain regions. ERCC1 expression was localized to the nuclei of neurons and astrocytes. (2) ERCC1 expression, as determined by western blot, increased at 3 days, remaining until 14 days, in the ipsilateral cortex and striatum following MCAO. Immunohistochemical analysis demonstrated that ischemia induced increased ERCC1 expression within the periinfarct core, with increasingly less expression toward the core. (3) Knockdown of ERCC1 expression by intraventricular injection of antisense plasmids increased DNA damage and infarct volume in the ischemic brain. (4) ERCC1 overproduction, by injection of expression plasmids, significantly reduced infarct volume and the accumulation of DNA-damaged neurons. Taken together, these results indicate that both endogenous ERCC1 and exogenous ERCC1 have an important neuroprotective function in the brain. In addition, administration of ERCC1 to the brain could prove to be a successful strategy for neuronal protection against ischemic injury.


Assuntos
Isquemia Encefálica/prevenção & controle , Encéfalo/metabolismo , Reparo do DNA/fisiologia , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Infarto da Artéria Cerebral Média/metabolismo , Fármacos Neuroprotetores/farmacologia , Animais , Western Blotting , Encéfalo/patologia , Isquemia Encefálica/patologia , Dano ao DNA/efeitos dos fármacos , Dano ao DNA/fisiologia , DNA Antissenso , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Endonucleases/genética , Técnicas de Silenciamento de Genes , Proteínas de Fluorescência Verde/metabolismo , Infarto da Artéria Cerebral Média/patologia , Masculino , Fármacos Neuroprotetores/administração & dosagem , Plasmídeos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes de Fusão/metabolismo , Coloração e Rotulagem , Fatores de Tempo , Distribuição Tecidual
3.
Shanghai Kou Qiang Yi Xue ; 5(1): 29-31, 1996 Mar.
Artigo em Zh | MEDLINE | ID: mdl-15160053

RESUMO

Expending dental-arch is one of the methods being used popularly in orthodontics.but there are few researches on its basical laws.In this paper,we used mathematic methods to discuss the relationship of the arch-length(S),the width(A),and the length of dental-arch(H).We devised a mathematic model,hoping it could be useful to orthodontic therapy.

4.
J Lipid Res ; 34(8): 1451-5, 1993 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-8105016

RESUMO

Several lipases and their cofactors are involved in the absorption, transport, storage, and mobilization of lipids. As part of an effort to examine the role of these enzymes in plasma lipid metabolism and genetic susceptibility to atherosclerosis, we report the chromosomal mapping of their genes in mouse. Restriction fragment length variants for each gene were identified, typed in an interspecific cross, and tested for linkage to known chromosomal markers. The gene for pancreatic lipase resides on chromosome 19, while the gene for its cofactor, colipase, is on chromosome 17. A gene for a protein with sequence similarity to pancreatic lipase was tightly linked (no observed recombination) to the gene for pancreatic lipase, suggesting a gene cluster. The gene for hormone-sensitive lipase is near the gene cluster containing apolipoproteins C-II and E on chromosome 7. The gene for hepatic lipase is near the gene for apolipoprotein A-I on chromosome 9. The carboxyl ester lipase gene resides on chromosome 2. Previously, we have mapped the gene for lipoprotein lipase to chromosome 8. Thus, with the exception of pancreatic lipase and a related protein, these lipase genes, including several that are members of a gene family, are widely dispersed in the genome. Comparison of chromosomal locations for these genes in mouse and humans shows that the previously observed interspecies syntenies are preserved.


Assuntos
Mapeamento Cromossômico , Colipases/genética , Lipase/genética , Lipólise , Esterol Esterase/genética , Animais , Carboxilesterase , Hidrolases de Éster Carboxílico/genética , Marcadores Genéticos , Hormônios/farmacologia , Fígado/enzimologia , Escore Lod , Camundongos , Camundongos Endogâmicos C57BL , Família Multigênica , Pâncreas/enzimologia , Polimorfismo de Fragmento de Restrição , Software
5.
Genomics ; 18(2): 295-307, 1993 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-8288233

RESUMO

We report the chromosomal mapping of 43 loci for 40 randomly isolated mouse liver cDNA clones by linkage analysis in an interspecific backcross of ((C57BL/6J x Mus spretus) x C57BL/6J). The clones were sequenced from both sides and a subset was examined for expression in various mouse tissues. Fifteen of the 40 mapped cDNA clones are either identical or strongly related to known sequences in GenBank, while 25 represent new genes. Additional loci mapped in this cross include 53 simple sequence repeat polymorphisms and 40 restriction fragment length variants from previously characterized cDNA markers. Nine homologous human genes were identified for 7 mouse liver cDNA clones. One clone that maps to mouse chromosome 3 (D3Ucla1) identified a novel homologous segment (synteny) on human chromosome 18q23 (D18S372E). These studies provide linkage mapping and initial characterization of random cDNA clones that may provide a resource for the positional candidate cloning of disease genes.


Assuntos
Mapeamento Cromossômico , DNA Complementar/genética , Fígado , Animais , Linhagem Celular , Clonagem Molecular , Feminino , Humanos , Células Híbridas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Sequências Repetitivas de Ácido Nucleico
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA