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1.
Nat Rev Genet ; 15(6): 367-78, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24733023

RESUMO

Genes on the mammalian X chromosome are present in one copy in males and two copies in females. The complex mechanisms that regulate the X chromosome lead to evolutionary and physiological variability in gene expression between species, the sexes, individuals, developmental stages, tissues and cell types. In early development, delayed and incomplete X chromosome inactivation (XCI) in some species causes variability in gene expression. Additional diversity stems from escape from XCI and from mosaicism or XCI skewing in females. This causes sex-specific differences that manifest as differential gene expression and associated phenotypes. Furthermore, the complexity and diversity of X dosage regulation affect the severity of diseases caused by X-linked mutations.


Assuntos
Transtornos Cromossômicos , Cromossomos Humanos X , Regulação da Expressão Gênica , Doenças Genéticas Ligadas ao Cromossomo X , Caracteres Sexuais , Inativação do Cromossomo X , Animais , Transtornos Cromossômicos/genética , Transtornos Cromossômicos/metabolismo , Cromossomos Humanos X/genética , Cromossomos Humanos X/metabolismo , Feminino , Doenças Genéticas Ligadas ao Cromossomo X/genética , Doenças Genéticas Ligadas ao Cromossomo X/metabolismo , Humanos , Masculino , Mosaicismo
2.
J Anim Physiol Anim Nutr (Berl) ; 100(1): 46-52, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26351060

RESUMO

Hy-Line Gray commercial pullets were maintained under 8-h photoperiods, 16-h photoperiods and 16-h photoperiods supplemented with a diet containing 20 or 200 mg/kg melatonin (MEL) to investigate the role of MEL in sexual development. A total of 256 Hy-Line Gray commercial pullets were placed, four birds to a cage, in four similar light-proof rooms (8-h photoperiod) at 6 weeks of age. At 70 day, three rooms containing a total of 192 birds were transferred to a 16-h photoperiod, whereas 64 birds were maintained under the 8-h photoperiod. Diets containing MEL at 20 and 200 mg/kg were fed to birds in two of the rooms under 16-h photoperiods. Birds maintained under an 8-h photoperiod matured 11.25 day later than those maintained under a 16-h photoperiod (p < 0.05). The group of birds receiving 20 mg/kg MEL matured 1.19 day later than those maintained under the 16-h photoperiod and 10.06 day earlier than those maintained under the 8-h photoperiod. The group of birds receiving 200 mg/kg MEL matured 3.13 day later than those maintained under a 16-h photoperiod and 8.12 day earlier than those maintained under an 8-h photoperiod. The average body weight of birds maintained under the 8-h photoperiod was greater than that of birds maintained under the 16-h photoperiod (p < 0.05) and was similar between the different MEL groups. The abdominal fat weight was lower in 16L:8D group compared with 8L:16D group (p < 0.05). The concentrations of follicle-stimulating hormone, luteinizing hormone, oestrogen and insulin did not differ significantly among the groups. The melatonin concentration in 200 mg/kg melatonin group was higher than that observed in the other groups; however, this concentration did not differ significantly (p > 0.05). These data suggest that the birds did not perceive the final 8-h photoperiod as being part of the night when they were given the MEL diets; continuously high plasma MEL was not observed in birds that responded as if they were in constant darkness. However, the later maturity of the groups administered MEL diets compared with the groups maintained under a constant 16-h photoperiod clearly indicated that MEL has some influence on the sexual maturity of pullets.


Assuntos
Galinhas/fisiologia , Melatonina/farmacologia , Fotoperíodo , Maturidade Sexual/efeitos dos fármacos , Tecido Adiposo , Ração Animal/análise , Animais , Peso Corporal , Suplementos Nutricionais , Feminino , Melatonina/administração & dosagem , Músculo Esquelético/fisiologia , Oviposição
3.
Genet Mol Res ; 14(2): 5793-803, 2015 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-26125778

RESUMO

We observed the influence of different concentrations of Rhizoma paridis total saponins (RPTS) on the apoptosis of colorectal cancer cells and explored the internal mechanism involved. We determined whether RPTS influences the interleukin-6 (IL-6)/Janus kinase (JAK)-signal transducer and activator of transcription-3 (STAT3) apoptosis molecular pathway and looked for colon cancer-related signal transduction pathways or targets inducing apoptosis. We also cultured SW480 colorectal cancer cells using different concentrations of RPTS (10, 20, 40, and 80 µg/ mL), and observed the effect of RPTS on SW480 cell morphology under a fluorescence inverted microscope. We detected serum IL-6 using the polymerase chain reaction and the expression of JAK-STAT3 protein by western blot. After treating SW480 with RPTS and Hoechst 33258 dyeing, we found that the typical apoptosis morphology had changed. Secretion of IL-6 in the serum decreased significantly (P < 0.05), and STAT3 levels were reduced. RPTS can significantly promote apoptosis in SW480 colorectal cancer cells. The mechanism may be that it suppresses the secretion of IL-6 and inhibits the IL-6/JAK-STAT3 protein signaling pathway.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Interleucina-6/biossíntese , Janus Quinases/biossíntese , Saponinas/administração & dosagem , Apoptose/efeitos dos fármacos , Apoptose/genética , Linhagem Celular Tumoral , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/genética , Janus Quinases/genética , Fosforilação , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Fator de Transcrição STAT3/biossíntese , Fator de Transcrição STAT3/genética , Saponinas/química , Transdução de Sinais/efeitos dos fármacos
4.
Sci Robot ; 7(62): eabj6660, 2022 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-35044796

RESUMO

The lunar nearside has been investigated by many uncrewed and crewed missions, but the farside of the Moon remains poorly known. Lunar farside exploration is challenging because maneuvering rovers with efficient locomotion in harsh extraterrestrial environment is necessary to explore geological characteristics of scientific interest. Chang'E-4 mission successfully targeted the Moon's farside and deployed a teleoperated rover (Yutu-2) to explore inside the Von Kármán crater, conveying rich information regarding regolith, craters, and rocks. Here, we report mobile exploration on the lunar farside with Yutu-2 over the initial 2 years. During its journey, Yutu-2 has experienced varying degrees of mild slip and skid, indicating that the terrain is relatively flat at large scales but scattered with local gentle slopes. Cloddy soil sticking on its wheels implies a greater cohesion of the lunar soil than encountered at other lunar landing sites. Further identification results indicate that the regolith resembles dry sand and sandy loam on Earth in bearing properties, demonstrating greater bearing strength than that identified during the Apollo missions. In sharp contrast to the sparsity of rocks along the traverse route, small fresh craters with unilateral moldable ejecta are abundant, and some of them contain high-reflectance materials at the bottom, suggestive of secondary impact events. These findings hint at notable differences in the surface geology between the lunar farside and nearside. Experience gained with Yutu-2 improves the understanding of the farside of the Moon, which, in return, may lead to locomotion with improved efficiency and larger range.

6.
Poult Sci ; 86(5): 917-20, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17435026

RESUMO

This paper is concerned with the effects of photoperiod on ovarian morphology and carcass traits at sexual maturity in egg-type hens. Two hundred fifty-six commercial egg-type pullets were initially subjected to a photoperiod of 23L:1D, which was reduced to 22L:2D at 1 wk, to 18L:6D at 2 wk, and to 16L:8D at 3 wk. From 4 to 20 wk, the photoperiod was 8L:16D. At 20 wk, 32 pullets were individually caged in individually lit cages, with 8 cages per unit. Two cage units were placed into 4 photoperiods of 17L:7D, 15L:9D, 13L:11D, and 11L:13D, respectively. Each bird was processed when it reached sexual maturity (SM), and carcass and ovarian morphology were assessed. The results showed that photoperiod had an effect on the timing of SM, and the age at first egg was 5.7 d earlier for hens exposed to the 17L:7D photoperiod than the 11L:13D photoperiod. However, photoperiod had no effect on BW at SM. A photoperiod of 11L:13D limited ovarian follicle formation and increased carcass protein and lipid compared with birds on longer photoperiods, whereas the 17L:7D photoperiod restricted ovary and oviduct full development. These results indicated that excessively long and short photoperiods can restrict reproductive development in egg-type hens.


Assuntos
Composição Corporal/fisiologia , Galinhas/fisiologia , Ovário/anatomia & histologia , Fotoperíodo , Maturidade Sexual/fisiologia , Animais , Feminino
7.
Sci Rep ; 5: 10153, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25950082

RESUMO

Spin-wave nonreciprocity arising from dipole-dipole interaction is insignificant for magnon wavelengths in the sub-100 nm range. Our micromagnetic simulations reveal that for the nanoscale magnonic crystals studied, such nonreciprocity can be greatly enhanced via synthetic antiferromagnetic coupling. The nonreciprocity is manifested as highly asymmetric magnon dispersion curves of the magnonic crystals. Furthermore, based on the study of the dependence of the nonreciprocity on an applied magnetic field, the antiparallel alignment of the magnetizations is shown to be responsible for the enhancement. Our findings would be useful for magnonic and spintronics applications.

8.
Am J Trop Med Hyg ; 63(1-2): 94-101, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11358004

RESUMO

A new virus named Sitiawan virus (SV) was isolated from sick broiler chicks in chicken embryos. The virus replicated well with cytopathogenic effect (CPE) in the chicken B-lymphocyte cell line LSCC-BK3. The virus was an enveloped RNA virus of approximately 41 nm in size with hemagglutinating activity (HA) to goose erythrocytes. It was cross-reactive with Japanese encephalitis virus (JEV), a member of flaviviruses by HA inhibition tests but not by cross-virus neutralization tests. The cDNA fragment of NS5 gene was amplified with primers corresponding to NS5 gene of flaviviruses. The nucleotide sequences were 92% homologous to Tembusu virus, a member of the mosquito-borne virus cluster of the genus Flavivirus. In cross-neutralization tests with Tembusu virus, antiserum to SV did not neutralize Tembusu virus, and antiserum to Tembusu virus neutralized more weakly to SV than against homologous virus. These results indicate that SV is a new virus which can be differentiated serologically from Tembusu virus but is otherwise similar with respect to nucleotide sequence. The virus causes encephalitis, growth retardation, and increased blood glucose levels in inoculated chicks.


Assuntos
Galinhas , Encefalite Viral/veterinária , Infecções por Flavivirus/veterinária , Flavivirus/isolamento & purificação , Flavivirus/patogenicidade , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Animais , Embrião de Galinha/crescimento & desenvolvimento , Embrião de Galinha/virologia , Galinhas/crescimento & desenvolvimento , Primers do DNA , DNA Viral/isolamento & purificação , Encefalite Viral/epidemiologia , Encefalite Viral/virologia , Flavivirus/genética , Flavivirus/ultraestrutura , Infecções por Flavivirus/epidemiologia , Infecções por Flavivirus/virologia , Malásia/epidemiologia , Doenças das Aves Domésticas/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Organismos Livres de Patógenos Específicos
9.
Biosens Bioelectron ; 17(6-7): 573-84, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11959480

RESUMO

Surface plasmon resonance (SPR) biosensors offer the capability for continuous real-time monitoring. The commercial instruments available have been large in size, expensive, and not amenable to field applications. We report here an SPR sensor system based on a prototype two-channel system similar to the single channel Spreeta devices. This system is an ideal candidate for field use. The two-channel design provides a reference channel to compensate for bulk refractive index (RI), non-specific binding and temperature variations. The SPR software includes a calibration function that normalizes the response from both channels, thus enabling accurate referencing. In addition, a temperature-controlled enclosure utilizing a thermo-electric module based on the Peltier effect provides the temperature stability necessary for accurate measurements of RI. The complete SPR sensor system can be powered by a 12V battery. Pre-functionalized, disposable, gold-coated thin glass slides provide easily renewable sensor elements for the system. Staphylococcus aureus enterotoxin B (SEB), a small protein toxin was directly detectable at sub-nanomolar levels and with amplification at femtomolar levels. A regeneration procedure for the sensor surface allowed for over 60 direct detection cycles in a 1-month period.


Assuntos
Enterotoxinas/análise , Imunoensaio/instrumentação , Imunoensaio/métodos , Ressonância de Plasmônio de Superfície/instrumentação , Ressonância de Plasmônio de Superfície/métodos , Animais , Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Materiais Revestidos Biocompatíveis/química , Enterotoxinas/imunologia , Desenho de Equipamento , Vidro/química , Cabras , Ouro/química , Microquímica , Leite/química , Miniaturização , Modelos Teóricos , Coelhos , Água do Mar/química , Sensibilidade e Especificidade , Temperatura , Fatores de Tempo , Urina/química
10.
Vestn Otorinolaringol ; (5): 69-71, 1990.
Artigo em Russo | MEDLINE | ID: mdl-2267701

RESUMO

The advantages of the method of endonasal vibromassage with air pressure oscillations (at 10-12 Hz and 24-30 mm Hg) are: lack of injuries, lack of pain, and simultaneous effect on all nasal and nasopharyngeal structures. The application of endonasal vibropneumomassage in patients with vasomotor rhinitis proved effective in the case of the nervous form of the disease lasting for no longer than a year.


Assuntos
Massagem , Nariz , Rinite Vasomotora/terapia , Vibração , Humanos , Fatores de Tempo
11.
Oncogene ; 32(42): 5038-47, 2013 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23178488

RESUMO

TRIM11 (tripartite motif-containing protein 11), an E3 ubiquitin ligase, is known to be involved in the development of the central nervous system. However, very little is known regarding the role of TRIM11 in cancer biology. Here, we examined the expression profile of TRIM11, along with two stem cell markers CD133 and nestin, in multiple glioma patient specimens, glioma primary cultures derived from tumors taken at surgery and normal neural stem/progenitor cells (NSCs). The oncogenic function of TRIM11 in glioma biology was investigated by knockdown and/or overexpression in vitro and in vivo experiments. Our results showed that TRIM11 expression levels were upregulated in malignant glioma specimens and in high-grade glioma-derived primary cultures, whereas remaining low in glioblastoma multiforme (GBM) stable cell lines, low-grade glioma-derived primary cultures and NSCs. The expression pattern of TRIM11 strongly correlated with that of CD133 and nestin and differentiation status of malignant glioma cells. Knock down of TRIM11 inhibited proliferation, migration and invasion of GBM cells, significantly decreased epidermal growth factor receptor (EGFR) levels and mitogen-activated protein kinase activity, and downregulated HB-EGF (heparin-binding EGF-like growth factor) mRNA levels. Meanwhile, TRIM11 overexpression promoted a stem-like phenotype in vitro (tumorsphere formation) and enhanced glial tumor growth in immunocompromised mice. These findings suggest that TRIM11 might be an indicator of glioma malignancy and has an oncogenic function mediated through the EGFR signaling pathway. TRIM11 overexpression potentially leads to a more aggressive glioma phenotype, along with increased malignant tumor growth and poor survival. Taken together, clarification of the biological function of TRIM11 and pathways it affects may provide novel therapeutic strategies for treating malignant glioma patients.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Glioma/patologia , Ubiquitina-Proteína Ligases/genética , Antígeno AC133 , Adulto , Idoso , Animais , Antígenos CD/genética , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Diferenciação Celular , Movimento Celular , Proliferação de Células , Ciclina D1/genética , Receptores ErbB/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Glioblastoma/genética , Glioblastoma/patologia , Glioma/metabolismo , Glioma/mortalidade , Glicoproteínas/genética , Fator de Crescimento Semelhante a EGF de Ligação à Heparina , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Nestina/genética , Oncogenes , Peptídeos/genética , Transdução de Sinais , Proteínas com Motivo Tripartido , Células Tumorais Cultivadas , Ubiquitina-Proteína Ligases/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Oncogene ; 27(32): 4456-66, 2008 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-18372912

RESUMO

Id-1 (Inhibitor of DNA binding/differential-1) plays a positive role in tumorigenesis through regulation of multiple signaling pathways. Recently, it is suggested that upregulation of Id-1 in cancer cells promotes chromosomal instability. However, the underlying molecular mechanism is not known. In this study, we report a novel function of Id-1 in regulation of mitosis through physical interaction with Cdc20 (cell division cycle protein 20) and Cdh1 (Cdc20 homolog 1). During early mitosis, Id-1 interacts with Cdc20 and RASSF1A (Ras association domain family 1A), leading to enhanced APC(Cdc20) activity, which in turn promotes cyclin B1/securin degradation and premature mitosis. During late mitosis, Id-1 binds to Cdh1 and disrupts the interaction between Cdh1 and APC, resulting in suppression of APC(Cdh1) activity. On the other hand, overexpression of Cdh1 leads to Id-1 protein degradation, suggesting that Id-1 may also act as a substrate of APC(Cdh1). The negative effect of Id-1 on APC(Cdh1) results in suppression of APC(Cdh1)-induced Aurora A and Cdc20 degradation, leading to failure in cytokinesis. As a result, overexpression of Id-1 in human prostate epithelial cells leads to polyploidy in response to microtubule disruption, and this effect is abolished when Id-1 expression is suppressed using antisense technology. These results demonstrate a novel function of Id-1 in promoting chromosomal instability through modification of APC/C activity during mitosis and provide a novel molecular mechanism accounted for the function of Id-1 as an oncogene.


Assuntos
Proteínas de Ciclo Celular/fisiologia , Instabilidade Cromossômica , Proteína 1 Inibidora de Diferenciação/fisiologia , Microtúbulos/fisiologia , Mitose , Complexos Ubiquitina-Proteína Ligase/fisiologia , Ciclossomo-Complexo Promotor de Anáfase , Aurora Quinases , Proteínas Cdc20 , Linhagem Celular , Ciclina B/metabolismo , Ciclina B1 , Fase G1 , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Supressoras de Tumor/fisiologia , Ubiquitina/metabolismo
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