Embryo implantation into the maternal uterus is a crucial step for the successful establishment of mammalian pregnancy. Following the attachment of embryo to the uterine luminal epithelium, uterine ...stromal cells undergo steroid hormone-dependent decidualization, which is characterized by stromal cell proliferation and differentiation. The mechanisms underlying steroid hormone-induced stromal cell proliferation and differentiation during decidualization are still poorly understood. Ribonucleotide reductase, consisting of two subunits (RRM1 and RRM2), is a rate-limiting enzyme in deoxynucleotide production for DNA synthesis and plays an important role in cell proliferation and tumorgenicity. Based on our microarray analysis, Rrm2 expression was significantly higher at implantation sites compared with interimplantation sites in mouse uterus. However, the expression, regulation, and function of RRM2 in mouse uterus during embryo implantation and decidualization are still unknown. Here we show that although both RRM1 and RRM2 expression are markedly induced in mouse uterine stromal cells undergoing decidualization, only RRM2 is regulated by progesterone, a key regulator of decidualization. Further studies showed that the induction of progesterone on RRM2 expression in stromal cells is mediated by the AKT/c-MYC pathway. RRM2 can also be induced by replication stress and DNA damage during decidualization through the ATR/ATM-CHK1-E2F1 pathway. The weight of implantation sites and deciduoma was effectively reduced by specific inhibitors for RRM2. The expression of decidual/trophoblast prolactin-related protein (Dtprp), a reliable marker for decidualization in mice, was significantly reduced in deciduoma and steroid-induced decidual cells after HU treatment. Therefore, RRM2 may be an important effector of progesterone signaling to induce cell proliferation and decidualization in mouse uterus.
Background: Ribonucleotide reductase M2 (RRM2) is a rate-limiting step for DNA synthesis. It is still unknown how RRM2 is involved in decidualization.
Results: RRM2 is highly expressed in the decidua and up-regulated by progesterone and DNA damage. Decidualization is significantly inhibited by specific RRM2 inhibitors.
Conclusion: RRM2 is essential for mouse decidualization.
Significance: This study will shed light on understanding the mechanism underlying decidualization.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
This study determined the prevalence of lifetime and current smoking and the correlates of current smoking in nurses working in psychiatric and general hospitals in China. Of 807 distributed ...questionnaires, 799 nurses who were working in two psychiatric hospitals (n=387, 48.4%), and one general hospital (n=412, 51.6%) had analyzable data. Socio-demographic, alcohol use and smoking data were collected with a self-reported questionnaire. Work-related stress was evaluated with the Nurse Stress Inventory. In the whole sample, the lifetime smoking prevalence was 7.6% (females=2.1% vs. males=48.9%, p<0.0001; psychiatric nurses=14.5% vs. non-psychiatric nurses=1.2%, p<0.0001). The prevalence of current smoking was 7.1% (females=2.1% vs. males=44.7%, p<0.0001; psychiatric nurses=13.4% vs. non-psychiatric nurses=1.2%, p<0.0001). In a multiple logistic regression analysis, age 30 years or older, male gender, having children, being a psychiatric nurse and alcohol consumption were positively associated with smoking, while being a nursing officer was negatively associated with smoking (r2 = 0.513, p<0.0001). Considering the harmful effects of smoking as well as second-hand smoking in the presence of children, effective measures to promote smoking cessation for male, older and psychiatric nurses and those with children are warranted.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, VSZLJ
This paper characterizes the rarely mentioned but very damaging defects formed during the hot-cutting process of alumina green tape. Surface and edge morphologies of the hot-cutting surface and a ...natural surface were examined by optical microscope and scanning electron microscope before and after the sintering process. Obviously different from the natural surface, the hot-cutting surface had a transverse crack-like defect scattered over the surface and a tearing, notch-like defect on the lower edge. A 31 × 22 full factorial experiment was conducted to evaluate the flexural strength controlled by the hot-cutting defect and inherent defects in ceramics. Variance analysis revealed a significant interaction between surface and wearing. The wearing factor had a statistically significant impact on the fracture strength of the top surface but not that of the side and bottom surfaces.
Full text
Available for:
IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Background Determination of the proper orientation of the knee articular surface is required both for correction of knee malalignment by osteotomy and for correct component alignment in knee ...arthroplasty. We sought to determine whether the patients＇ sex and lower extremity alignment （hip-knee-ankle angle） affects proper knee realignment in osteotomy or component alignment in total knee arthroplasty. Methods We examined 199 healthy adult knees with malalignment of 〈5°to determine the mechanical medial distal femoral angle, mechanical medial proximal tibial angle, surgical transepicondylar axis angle, and discrepancies between bone-cut orientations of osteotomy or total knee arthroplasty and the joint line of the distal femoral condyles, posterior femoral condyles and proximal tibial plateaus, using a three-dimensional computed tomography model. Results The mean mechanical medial distal femoral angle and mean mechanical medial proximal tibial angle were （94.4±1.9）° and （87.6±1.8）° respectively for women and （93.8±2.0）° and （87.1±1.4）° respectively for men. The surgical transepicondylar axis angle was （2.9±1.6）° for women and （3.2±1.7）° for men. Independent of sex, the hip-knee-ankle angle was closely related to the mechanical medial distal femoral angle and mechanical medial proximal tibial angle, but not to the surgical transepicondylar axis angle. A slightly more valgus alignment of the knee and a more valgus angulation of the distal femoral joint line were found in women, whereas a more varus angulation of the proximal tibial joint line was found in men. Sex had the greatest effect on knee joint line orientation when the lower extremity was valgus in alignment. Conclusions A more valgus femoral joint line can be expected in women and in persons with valgus lower extremity aliqnment; a more varus tibial joint line can be found in men and in persons with varus lower extremity alignment.
In insects, the sense of smell is mainly mediated by olfactory receptors (Ors). Olfactory co-receptor (Orco), which is co-expressed with the Ors in almost all olfactory receptor neurons (ORNs), is ...demonstrated to be an essential component in the insect olfactory system. It can be potential target for developing novel olfactory-disruption strategy to control insect pests. In this study, two full-length cDNA sequences encoding Orcos (CmedOrco and ChsupOrco) were cloned from two Lepidopteran rice pests, the rice leaffolder, Cnaphalocrocis medinalis and the rice striped stem borer, Chilo suppressalis. The amino acid sequences of CmedOrco and ChsupOrco showed high similarity to the previously identified Orcos from other insect species. Bioinformatic prediction and cellular immunofluorescence indicated that CmedOrco and ChsupOrco were both seven-transmembrane proteins with intracellular N-termini and extracellular C-termini. mRNA expression levels of the two Orcos were much higher in male and female antennae than those in non-olfactory tissues, and the ChsupOrco transcripts reached a peak level in adults compared to other life stages. Our results provide a foundation from which it will be possible to elucidate the roles of Orco in moth olfaction and for the development of environment-friendly management strategies of these two rice insect pests.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Rheumatoid arthritis (RA) is a common disease characterized by chronic inflammation and irreversible destruction of articular cartilage and bone. In this report, we examined the anti-inflammatory and ...anti-arthritic effects of a novel leflunomide analogue, UTL-5b (also known as GBL-5b), for potential RA treatment. Using a carrageenan-induced edema study in rats, UTL-5b exhibited a better anti-inflammatory effect as compared with leflunomide and its metabolite. The chronic efficacy of UTL-5b was examined using type II collagen-induced arthritis (CIA) mouse model. UTL-5b exerted an anti-arthritic effect in a dose-dependant manner with mice given 30 mg/kg exhibiting amelioration of disease early in the trial, but losing statistical significance over time. In contrast, mice treated with 60 mg/kg showed reduced clinical disease parameters early in the trial and these effects were sustained over the ten week trial period. Mechanistic studies indicate that UTL-5b is an inhibitor of TNF-α production in vivo. Oral administration of UTL-5b prior to i.p. injection with lethal dose of lipopolysaccharide (LPS)/D-galactosamine markedly reduced the levels of serum TNF-α and increased survival rates of animals from septic shock-induced death. Acute toxicity study using mice receiving increasing doses of UTL-5b showed that no animals were killed by UTL-5b at 2,000 mg/kg (LD(50) >2,000 mg/kg). Our studies show that UTL-5b represents a novel anti-inflammatory and anti-arthritic agent with potential therapeutic application for RA treatment.
In this paper, the hot cutting surface and edge formed at green state are characterized and researched. Surface morphology of the hot-cutting green state and co-fired state is observed by optical ...microscope and SEM, and compared with that of the natural surface that formed in tape casting. The Weibull statistical strength test is introduced to evaluate the influence to the quality and reliability and the fractography is examined and analysed by optical microscope and SEM. Comparing the hot-cutting surface and edge before and after co-firing shows the great similarity with each other, which indicate the firing process can't cure the damage occurred in hot-cutting process, while the comparing between the hot-cutting surface and natural surface shows the hot-cutting surface is not only much coarser, but also with ravine-like defect on the surface and defect scraggly-like at the edge. The Weibull statistical strength test reveals the two-kinds of defect leads to a remarkable decrease in strength and also a increasing variability, which means a lower reliability compared to the natural surface. The fractography analysis shows the ravine-like defect introduced at the edge is more dangerous than the defect on the surface and the natural defect inside the volume.
In insects,the sense of smell is mainly mediated by olfactory receptors（Ors）.Olfactory co-receptor（Orco）,which is coexpressed with the Ors in almost all olfactory receptor neurons（ORNs）,is ...demonstrated to be an essential component in the insect olfactory system.It can be potential target for developing novel olfactory-disruption strategy to control insect pests.In this study,two full-length cDNA sequences encoding Orcos（CmedOrco and ChsupOrco） were cloned from two Lepidopteran rice pests,the rice leaffolder,Cnaphalocrocis medinalis and the rice striped stem borer,Chilo suppressalis.The amino acid sequences of CmedOrco and ChsupOrco showed high similarity to the previously identified Orcos from other insect species. Bioinformatic prediction and cellular immunofluorescence indicated that CmedOrco and ChsupOrco were both seven-transmembrane proteins with intracellular N-termini and extracellular C-termini.mRNA expression levels of the two Orcos were much higher in male and female antennae than those in non-olfactory tissues,and the ChsupOrco transcripts reached a peak level in adults compared to other life stages.Our results provide a foundation from which it will be possible to elucidate the roles of Orco in moth olfaction and for the development of environment-friendly management strategies of these two rice insect pests.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
30.
词义的动态范畴化在语言不同维度上的实现 Zeng, Rong
Wai yu jiao xue yu yan jiu,
01/2020, Volume:
52, Issue:
1
Journal Article
Dynamic categorization refers to the immediate change or diachronic evolution of semantic categories at the lexical, sentence and discourse meaning levels under the influence of metaphor, metonymy, ...base/profile and other working mechanisms. From the perspective of "dynamic categorization" in cognitive linguistics, this paper analyzes the performance of dynamic categorization of word meaning in different dimensions of language, so as to make a reasonable interpretation of its derivations. It is found that, at the word meaning level, this categorization is all about lexical features and relations. At the sentence level, it is mainly about categorization of grammatical terms and the structural relationships. At the level of discourse, it is chiefly about the categorization of the evaluation meaning.
PDF
