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1.
Sci Robot ; 7(62): eabj6660, 2022 Jan 19.
Article in English | MEDLINE | ID: mdl-35044796

ABSTRACT

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.

2.
J Anim Physiol Anim Nutr (Berl) ; 100(1): 46-52, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26351060

ABSTRACT

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.


Subject(s)
Chickens/physiology , Melatonin/pharmacology , Photoperiod , Sexual Maturation/drug effects , Adipose Tissue , Animal Feed/analysis , Animals , Body Weight , Dietary Supplements , Female , Melatonin/administration & dosage , Muscle, Skeletal/physiology , Oviposition
3.
Genet Mol Res ; 14(2): 5793-803, 2015 May 29.
Article in English | MEDLINE | ID: mdl-26125778

ABSTRACT

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.


Subject(s)
Colorectal Neoplasms/drug therapy , Interleukin-6/biosynthesis , Janus Kinases/biosynthesis , Saponins/administration & dosage , Apoptosis/drug effects , Apoptosis/genetics , Cell Line, Tumor , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Gene Expression Regulation, Neoplastic/drug effects , Humans , Interleukin-6/genetics , Janus Kinases/genetics , Phosphorylation , Plant Extracts/administration & dosage , Plant Extracts/chemistry , STAT3 Transcription Factor/biosynthesis , STAT3 Transcription Factor/genetics , Saponins/chemistry , Signal Transduction/drug effects
4.
Sci Rep ; 5: 10153, 2015 May 07.
Article in English | MEDLINE | ID: mdl-25950082

ABSTRACT

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.

5.
Nat Rev Genet ; 15(6): 367-78, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24733023

ABSTRACT

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.


Subject(s)
Chromosome Disorders , Chromosomes, Human, X , Gene Expression Regulation , Genetic Diseases, X-Linked , Sex Characteristics , X Chromosome Inactivation , Animals , Chromosome Disorders/genetics , Chromosome Disorders/metabolism , Chromosomes, Human, X/genetics , Chromosomes, Human, X/metabolism , Female , Genetic Diseases, X-Linked/genetics , Genetic Diseases, X-Linked/metabolism , Humans , Male , Mosaicism
7.
Oncogene ; 32(42): 5038-47, 2013 Oct 17.
Article in English | MEDLINE | ID: mdl-23178488

ABSTRACT

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.


Subject(s)
Brain Neoplasms/genetics , Glioma/genetics , Glioma/pathology , Ubiquitin-Protein Ligases/genetics , AC133 Antigen , Adult , Aged , Animals , Antigens, CD/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/mortality , Brain Neoplasms/pathology , Cell Differentiation , Cell Movement , Cell Proliferation , Cyclin D1/genetics , ErbB Receptors/genetics , Female , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , Glioblastoma/genetics , Glioblastoma/pathology , Glioma/metabolism , Glioma/mortality , Glycoproteins/genetics , Heparin-binding EGF-like Growth Factor , Humans , Intercellular Signaling Peptides and Proteins/genetics , Male , Mice , Mice, Inbred BALB C , Middle Aged , Mitogen-Activated Protein Kinases/metabolism , Nestin/genetics , Oncogenes , Peptides/genetics , Signal Transduction , Tripartite Motif Proteins , Tumor Cells, Cultured , Ubiquitin-Protein Ligases/metabolism , Xenograft Model Antitumor Assays
8.
Oncogene ; 27(32): 4456-66, 2008 Jul 24.
Article in English | MEDLINE | ID: mdl-18372912

ABSTRACT

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.


Subject(s)
Cell Cycle Proteins/physiology , Chromosomal Instability , Inhibitor of Differentiation Protein 1/physiology , Microtubules/physiology , Mitosis , Ubiquitin-Protein Ligase Complexes/physiology , Anaphase-Promoting Complex-Cyclosome , Aurora Kinases , Cdc20 Proteins , Cell Line , Cyclin B/metabolism , Cyclin B1 , G1 Phase , Humans , Protein Serine-Threonine Kinases/metabolism , Tumor Suppressor Proteins/physiology , Ubiquitin/metabolism
9.
Poult Sci ; 86(5): 917-20, 2007 May.
Article in English | MEDLINE | ID: mdl-17435026

ABSTRACT

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.


Subject(s)
Body Composition/physiology , Chickens/physiology , Ovary/anatomy & histology , Photoperiod , Sexual Maturation/physiology , Animals , Female
10.
Biosens Bioelectron ; 17(6-7): 573-84, 2002 Jun.
Article in English | MEDLINE | ID: mdl-11959480

ABSTRACT

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.


Subject(s)
Enterotoxins/analysis , Immunoassay/instrumentation , Immunoassay/methods , Surface Plasmon Resonance/instrumentation , Surface Plasmon Resonance/methods , Animals , Biosensing Techniques/instrumentation , Biosensing Techniques/methods , Coated Materials, Biocompatible/chemistry , Enterotoxins/immunology , Equipment Design , Glass/chemistry , Goats , Gold/chemistry , Microchemistry , Milk/chemistry , Miniaturization , Models, Theoretical , Rabbits , Seawater/chemistry , Sensitivity and Specificity , Temperature , Time Factors , Urine/chemistry
11.
Am J Trop Med Hyg ; 63(1-2): 94-101, 2000.
Article in English | MEDLINE | ID: mdl-11358004

ABSTRACT

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.


Subject(s)
Chickens , Encephalitis, Viral/veterinary , Flavivirus Infections/veterinary , Flavivirus/isolation & purification , Flavivirus/pathogenicity , Poultry Diseases/epidemiology , Poultry Diseases/virology , Animals , Chick Embryo/growth & development , Chick Embryo/virology , Chickens/growth & development , DNA Primers , DNA, Viral/isolation & purification , Encephalitis, Viral/epidemiology , Encephalitis, Viral/virology , Flavivirus/genetics , Flavivirus/ultrastructure , Flavivirus Infections/epidemiology , Flavivirus Infections/virology , Malaysia/epidemiology , Poultry Diseases/blood , Reverse Transcriptase Polymerase Chain Reaction/veterinary , Specific Pathogen-Free Organisms
12.
Vestn Otorinolaringol ; (5): 69-71, 1990.
Article in Russian | MEDLINE | ID: mdl-2267701

ABSTRACT

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.


Subject(s)
Massage , Nose , Rhinitis, Vasomotor/therapy , Vibration , Humans , Time Factors
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