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Establishment of cellular polarity is one of the key events during oocyte maturation. Inscuteable (Insc) has been identified as a key regulator of cell polarity during asymmetric division in Drosophila. However, the function of its evolutionarily conserved mammalian homologue, mInscuteable (mInsc), in mouse meiotic maturation is not clear. In this study, we investigated the roles of mInsc in mouse oocyte maturation. mInsc was detected at all stages of oocyte maturation. The protein level of mInsc was slightly higher at the germinal vesicle breakdown (GVBD) stage and remained constant during mouse oocyte maturation. The subcellular localization of mInsc overlapped with spindle microtubules. Disruption of microtubules and microfilaments caused changes in the localization of mInsc. Depletion or overexpression of mInsc significantly decreased the maturation rates of mouse oocytes. Depletion of mInsc significantly affected asymmetric division, spindle assembly, alignments of chromosomes and actin cap formation. Taken together, our results demonstrated that mInsc regulates meiotic spindle organization during mouse meiotic maturation.
Annexin A2 (ANXA2) is reported to be associated with cancer development. To investigate the roles ANXA2 plays during the development of cancer, the RNAi method was used to inhibit the ANXA2 expression in caco2 (human colorectal cancer cell line) and SMMC7721 (human hepatocarcinoma cell line) cells. The results showed that when the expression of ANXA2 was efficiently inhibited, the growth and motility of both cell lines were significantly decreased, and the development of the motility relevant microstructures, such as pseudopodia, filopodia, and the polymerization of microfilaments and microtubules were obviously inhibited. The cancer cell apoptosis was enhanced without obvious significance. The possible regulating pathway in the process was also predicted and discussed. Our results suggested that ANXA2 plays important roles in maintaining the malignancy of colorectal and hepatic cancer by enhancing the cell proliferation, motility, and development of the motility associated microstructures of cancer cells based on a possible complicated signal pathway.
Maternal one-carbon metabolism during pregnancy is crucial for fetal development and programming by DNA methylation. However, evidence on one-carbon biomarkers other than folate is lacking. We, therefore, investigated whether maternal plasma methyl donors, that is, choline, betaine and methionine, are associated with birth outcomes. Blood samples were obtained from 115 women during gestation (median 26·3 weeks, 90 % range 22·7–33·0 weeks). Plasma choline, betaine, methionine and dimethylglycine were measured using HPLC-tandem MS. Multivariate linear and logistic regression models were used to estimate the association between plasma biomarkers and birth weight, birth length, the risk of small-for-gestational-age and large-for-gestational-age (LGA). Higher level of maternal betaine was associated with lower birth weight (–130·3 (95 % CI –244·8, –15·9) per 1 sd increment for log-transformed betaine). Higher maternal methionine was associated with lower risk of LGA, and adjusted OR, with 95 % CI for 1 sd increase in methionine concentration was 0·44 (95 % CI 0·21, 0·89). Stratified analyses according to infant sex or maternal plasma homocysteine status showed that reduction in birth weight in relation to maternal betaine was only limited to male infants or to who had higher maternal homocysteine status (≥5·1 µmol/l). Higher maternal betaine status was associated with reduced birth weight. Maternal methionine was inversely associated with LGA risk. These findings are needed to be replicated in future larger studies.
The special application environment puts forward the higher requirement of reliability of parts made from titanium alloy Ti–6Al–4V, which is closely related to the machining-induced residual stress. For the fact of the non-linear distribution of residual stress beneath the machined surface, distribution of peripheral milling-induced residual stress and its effect on fatigue performance of titanium alloy Ti–6Al–4V are still confusing. In the present study, residual stress profile induced by peripheral milling of Ti–6Al–4V is first studied. And then, energy criteria are proposed to characterise the whole state of the residual stress field. Finally, the effects of residual stress profile and surface energy on tensile–tensile fatigue performance of titanium alloy Ti–6Al–4V are discussed. The conclusions were drawn that the variation trend of surface residual stress (σr,Sur), maximum compressive residual stress (σC,ax), location (hr0) and response depth (hry) of residual stress profile with cutting parameters showed a similar pattern for both measure directions those parallel (σ1) and perpendicular (σ3) to the cutting direction. Cutting speed and feed rate have a main effect on surface residual stress, and the depth of cut has little effect on all the four key factors of residual stress profile. With the increase of cutting speed and feed rate, machining-induced surface energy tends to become larger. But increasing the depth of cut caused the strain energy stored in unit time to decrease. Furthermore, the effect of depth of cut on surface energy was weakened when the value of cutting depth becomes larger. Both the surface compressive residual stress and the maximum compressive residual stress are beneficial for prolonging the fatigue life, while large value of machining-induced surface energy leads to a decrease of fatigue life. Analysis of variance result shows that maximum residual compressive stress has a greater impact on fatigue life than other residual stress factors.
Healthcare-associated infections (HAIs) are a major worldwide public-health problem, but less data are available on the long-term trends of HAIs and antimicrobial use in Eastern China. This study describes the prevalence and long-term trends of HAIs and antimicrobial use in a tertiary care teaching hospital in Hefei, Anhui, China from 2010 to 2017 based on annual point-prevalence surveys. A total of 12 505 inpatients were included; 600 HAIs were recorded in 533 patients, with an overall prevalence of 4.26% and a frequency of 4.80%. No evidence was found for an increasing or decreasing trend in prevalence of HAI over 8 years (trend χ2 = 2.15, P = 0.143). However, significant differences in prevalence of HAI were evident between the surveys (χ2 = 21.14, P < 0.001). The intensive care unit had the highest frequency of HAIs (24.36%) and respiratory tract infections accounted for 62.50% of all cases; Escherichia coli was the most common pathogen (16.67%). A 44.13% prevalence of antimicrobial use with a gradually decreasing trend over time was recorded. More attention should be paid to potential high-risk clinical departments and HAI types with further enhancement of rational antimicrobial use.
Nine possible native point defects in MgCaSi have been studied by employing density functional theory based ab initio calculations. The complex chemical potential limits are first determined using a two-dimension (∆μMg, ∆μCa) diagram, then the defect formation energies as a function of the atomic chemical potential are gained. The energetic results show that under Mg-rich conditions, the most favorable defect is MgCa rather than MgSi, while CaMg is predominant compared to CaSi under Ca-rich conditions. The bonding energy is first introduced to uncover the intrinsic feature of defect formation energy. The local geometric distortion around CaMg, MgSi, and CaSi antisite defects gradually increases due to the smaller atomic radii from Ca to Mg and Si, showing the important role of the geometrical mismatch. The density of states indicates that the higher stability of CaMg and MgCa originates from the smaller deviation of the Fermi level from the pseudo-gap.
Disclosing the diagnosis of Alzheimer's disease (AD) to a patient is controversial. There is significant stigma associated with a diagnosis of AD or dementia in China, but the attitude of the society toward disclosure of such a diagnosis had not been formally evaluated prior to our study. Therefore, we aimed to evaluate the attitude toward disclosing an AD diagnosis to patients in China with cognitive impairment from their caregivers, and the factors that may affect their attitude.
We designed a 17-item questionnaire and administered this questionnaire to caregivers, who accompanied patients with cognitive impairment or dementia in three major hospitals in Shanghai, China. The caregiver's attitude toward disclosing the diagnosis of AD as evaluated by the questionnaire was compared to that of disclosing the diagnosis of terminal cancer.
A majority (95.7%) of the 175 interviewed participants (mean 14.2 years of education received) wished to know their own diagnosis if they were diagnosed with AD, and 97.6% preferred the doctor to tell their family members if they were diagnosed with AD. If a family member of the participants suffered from AD, 82.9% preferred to have the diagnosis disclosed to the patient. “Cognitive impairment” was the most accepted term by caregivers to disclose AD diagnosis in Chinese.
This study suggests most of the well-educated individuals in a Chinese urban area favored disclosing the diagnosis when they or their family members were diagnosed with AD.
Salivary α-amylase (sAA) is responsible for the ‘pre-digestion’ of starch in the oral cavity and accounts for up to 50 % of salivary protein in human saliva. An accumulating body of literature suggests that sAA is of nutritional importance; however, it is still not clear how sAA is related to individual's nutritional status. Although copy number variations (CNV) of the salivary amylase gene (AMY1) are associated with variation in sAA levels, a significant amount of sAA variation is not explained by AMY1 CNV. To measure sAA responses to gustatory stimulation with citric acid, we used sAA ratio (the ratio of stimulated sAA levels to those of resting sAA) and investigated acute sAA responses to citric acid in children with normal (Normal-BMI, n 22) and low (Low-BMI, n 21) BMI. The AMY1 gene copy number was determined by quantitative PCR. We, for the first time, demonstrated attenuated acute sAA responses (decreased sAA ratio) to gustatory stimulation in Low-BMI (thinness grade 3) children compared with the Normal-BMI children, which suggest that sAA responses to gustatory stimulation may be of nutritional importance. However, child's nutritional status was not directly related to their resting or stimulated sAA levels, and it was not associated with AMY1 gene copy number. Finally, AMY1 CNV might influence, but did not eventually determine, sAA levels in children.
To assess correlations between cruciferous vegetable intake and urinary isothiocyanate (ITC) level, in addition to glutathione S-transferase (GST) genotypes and other individual factors.
The study included cohort participants whose urinary ITC levels had been previously ascertained. Urinary ITC was assessed using HPLC. Usual dietary intake of cruciferous vegetables was assessed using a validated FFQ and total dietary ITC intake was calculated. Recent cruciferous vegetable intake was determined. GST genotypes were assessed using duplex real-time quantitative PCR assays. Spearman correlations were calculated between the covariates and urinary ITC levels and linear regression analyses were used to calculate the mean urinary ITC excretion according to GST genotype.
Urban city in China.
The study included 3589 women and 1015 men from the Shanghai Women’s and Men’s Health Studies.
Median urinary ITC level was 1·61 nmol/mg creatinine. Self-reported usual cruciferous vegetable intake was weakly correlated with urinary ITC level (rs=0·1149; P<0·0001), while self-reported recent intake was more strongly correlated with urinary ITC (rs=0·2591; P<0·0001). Overall, the GST genotypes were not associated with urinary ITC level, but significant differences according to genotype were observed among current smokers and participants who provided an afternoon urine sample. Other factors, including previous gastrectomy or gastritis, were also related to urinary ITC level.
The study suggests that urinary secretion of ITC may provide additional information on cruciferous vegetable intake and that GST genotypes are related to urinary ITC level only in some subgroups.
Neurosyphilis (NS) may present with neuropsychiatric disorders characterized by cognitive impairment, personality disorders, and confusion, among others. Very few studies have focused on neuropsychiatric disorders secondary to NS in elderly people.
A retrospective chart review was performed to characterize the psychiatric findings, clinical signs and symptoms, laboratory findings, and brain magnetic resonance imaging results of ten elderly inpatients with NS.
In these ten patients, the most common presenting symptoms included a wide variety of psychiatric manifestations. The serum rapid plasma regain (RPR) and Treponema pallidum particle agglutination assay (TPPA) of the ten patients were positive, with positive CSF TPPA and RPR rates of 100% and 60%, respectively. In addition, 90% of the patients demonstrated abnormal imaging, including cerebral atrophy, infarct ischemic stroke, and hydrocephalus.
Our findings support the importance of serological tests for syphilis as a routine component of the evaluation of patients with clinically evident neurological or psychiatric symptoms. If the serology is positive, all of the patients should be examined with a lumbar puncture. Moreover, psychiatric illnesses secondary to NS in the elderly also deserve medical attention.
This paper is concerned with the Hopf bifurcation analysis of tumor-immune system competition model with two delays. First, we discuss the stability of state points with different kinds of delays. Then, a sufficient condition to the existence of the Hopf bifurcation is derived with parameters at different points. Furthermore, under this condition, the stability and direction of bifurcation are determined by applying the normal form method and the center manifold theory. Finally, a kind of Runge-Kutta methods is given out to simulate the periodic solutions numerically. At last, some numerical experiments are given to match well with the main conclusion of this paper.
Stone coal is an important vanadium-bearing resource in China. Most vanadium exists in stone coal as V(III), which is stable and not easily to be extracted. The V(III) should be oxidized to V(IV) and/or V(V) by roasting with additives at high temperature and then extracted by acid leaching and/or water leaching. Hence, the vanadium valency in roasted stone coal can reflect the roasting efficiency and leaching rate. In traditional digestion process, the V(V) can oxidize V(III) in solution and this causes great error to the determination of vanadium valency. In this study, the V(IV) and V(V) in roasted stone coal is dissolved firstly in 5% of hydrochloric acid at room temperature for 1h because the V(III) embedded in crystal lattice can not dissolve in dilute acid. The acid solution containing V(IV) and V(V) is titrated by 0.02 M ammonium ferrous sulfate (AFS), and the jump in titration curve indicates the reducing of V(V) to V(IV) by ferrous ion. The volume of V(V) can be calculated according to the consumption of AFS. The total volume of vanadium can be determined by potassium permanganate oxidation-ammonium ferrous sulfate titrimetric method. Hence, the volume of V(IV) can be obtained by deducting the quantity of V(V) from the total vanadium. Secondly, the undissolved residue is digested in Teflon vessel by phosphoric acid and hydrofluoric acid at 90 °C for 2h. The digestion solution is also titrated by AFS under nitrogen atmosphere, and the jump in titration curve denotes the reducing of V(IV) to V(III) by ferrous ion in phosphoric acid medium. So, the volume of V(III) and V(IV) can be obtained in the same way. This method is characterized by high measuring accuracy and excellent reproducibility.
Hypoxia inducible factor 1 (HIF-1) is a key transcriptional factor activated during cerebral ischemia, which regulates a great number of downstream genes, including those associated with cell death. In the present study, we aimed to test the hypothesis that post-ischemic HIF-1α up-regulation might promote autophagy activation; thereby, HIF-1α inhibitor 2ME2 might prevent neurons from ischemic injury through inhibiting autophagy.
Global ischemia was induced using the four-vessel occlusion model (4-VO) in Sprague-Dawley rats (male, 250-280g). 2-Methoxyestradiol (2ME2, 5mg/kg, i.p.) was administrated to down-regulate HIF-1α expression. Post-ischemic beclin-1 and LC3 protein expression was determined at different time points through Western blot assay. Neuronal injury was determined by cresyl violet staining and TUNEL staining in coronal histological sections.
The expression of beclin-1 and the ratio of LC3-II/LC3-I increased significantly at 12 and 24 h after ischemia. 2ME2 could remarkably inhibit the up-regulation of beclin-1 and the increase of LC3-II/LC3-I ratio during reperfusion. Moreover, 2ME2 and 3-MA exhibited powerful protective effects against ischemic/reperfusion induced neuronal injury.
This study confirmed that autophagy participated in post-ischemic neuronal injury. 2ME2, a HIF-1α inhibitor, might significantly decrease autophagy activation after cerebral ischemia and relieve post-ischemic neuronal injury. Our findings demonstrate that autophagy could be a potential target for neuronal protection after cerebral ischemia.
Although moissanite has been found in various rocks, reliable primary moissanite has been reported only from kimberlites and meteorites. The Dabie Mountain moissanite reported in this paper is the first occurrence of primary moissanite hosted by serpentinite. It differs from synthetic silicon carbide in optical properties, inclusions and infrared spectrum. The biaxiality of the Dabie Mountain moissanite is thought to be the result of intracrystal deformation. In reference to the ultrahigh pressure (7—8 GPa) signature of exsolution of rod-like apatite, clinopyroxene and rutile in garnets, and magnetite lamellae in olivine reported in the Dabieshan, we inferred that the moissanite from the Dabie Mountains was probably generated at a depth of 180 km; and then subducted to a depth of 210—250 km, where the moissanite became biaxial before its exhumation.
Semi-dwarfism is an important agronomic trait in rice breeding programmes. sd-1, termed the ‘Green Revolution gene’, confers semi-dwarf stature, increases harvest index, improves lodging resistance, and is associated with increased responsiveness to nitrogen fertilizer. It has contributed substantially to the significant increase in rice production. In this paper, a novel semi-dwarf mutant in rice is reported. Genetic analysis revealed that only a single dominant gene locus non-allelic to sd-1, temporarily designated Sdt97, is involved in the control of semi-dwarfism of the mutant. The semi-dwarfism of the mutant could be partly restored to the tall wild-type by application of exogenous GA3, suggesting that the mutant gene Sdt97 may be involved in the gibberellin (GA) synthesis pathway and not the GA response pathway in rice. A residual heterozygous line (RHL) population derived from a recombinant inbred line (RIL) was developed. Simple sequence repeat (SSR) and bulked segregation analysis (BSA) combined with recessive class analysis (RCA) techniques were used to map Sdt97 to the long arm of chromosome 6 at the interval between two STS markers, N6 and TX5, with a genetic distance of 0·2 cM and 0·8 cM, respectively. A contig map was constructed based on the reference sequence aligned by the Sdt97 linked markers. The physical map of the Sdt97 locus was defined to a 118 kb interval, and 19 candidate genes were detected in the target region. This is the first time that a dominant semi-dwarf gene has been reported in rice. Cloning and functional analysis of gene Sdt97 will help us to learn more about molecular mechanism of rice semi-dwarfism.
To increase our understanding of the relationships of trunk fat mass (FMtrunk) and four anthropometric indices in Chinese males, 1090 males aged 20–40 years were randomly recruited from the city of Changsha, China. Waist circumference (WC) and hip circumference (HC) were measured using standardized equipment, and three other anthropometric indices of BMI, waist:hip ratio (WHR) and conicity index (CoI) were calculated using weight, height, HC and WC. FMtrunk (in kg) was measured using a Hologic QDR 4500 W dual-energy X-ray absorptiometry scanner. There was an increasing trend of FMtrunk, %FMtrunk (percentage of FMtrunk) and BMI, WC, WHR, CoI in successively older age groups (e.g. the mean FMtrunk values were 4·63 (sd 2·58), 5·39 (sd 2·74), 5·93 (sd 2·82), 6·57 (sd 2·94) in four 5-year age groups, respectively). FMtrunk and %FMtrunk were significantly correlated with four anthropometric indices with the Pearson's correlation coefficients ranging from 0·25 to 0·86. Principal component analysis was performed to form three principal components that interpreted over 99·5% of the total variation of four related anthropometric indices in all age groups, with over 65% of the total variation accounted by principal component 1. Multiple regression analyses showed that three principal components explained a greater variance (R2 70·0–80·1%) in FMtrunk than did BMI or WC alone (R2 57·8–74·1%). The present results suggest that there is an increasing trend of FMtrunk and four anthropometric indices in successively older age groups; that age has important effects on the relationships of FMtrunk and studied anthropometric indices; and that the accuracy of predicting FMtrunk using four anthropometric indices is higher than using BMI or WC alone.
Myofibre composition in longissimus dorsi (LD) muscle of Erhualian (EHL) and Large White (LW) pigs was investigated by determining the ratios of mRNA abundances of four myosin heavy chain (MyHC) isoforms (MyHC I, MyHC 2a, MyHC 2x and MyHC 2b) using multiplex RT-PCR. The relationship between expression of growth hormone receptor (GHR) and peroxisome proliferator-activated receptor α coactivator-lα (PGC-lα) mRNAs and changes ofmyofibre type composition during postnatal growth from 3 to 180 days of age were analysed. At 3 days of age, proportions of MyHC I, 2a and 2x fibres were high while only a few MyHC 2b fibres were differentiated. Dramatic changes were observed from day 3 to day 20 with significantly decreased MyHC I, 2a and 2x fibres but abrupt increases in MyHC 2b fibres in both breeds of pigs. Breed difference was exhibited only from day 90, with higher MyHC 2b but less MyHC I and 2a expression in LW pigs. Developmental pattern of GHR mRNA expression in LD muscle coincided with that of MyHC 2b, with LW pigs expressing higher abundance of GHR mRNA. PGC-lα mRNA expression followed distinct patterns in the two breeds of pigs, a higher level of PGC-lα mRNA being expressed in LD muscle of EHL pigs, the breed that possessed more oxidative fibres (MyHC I and MyHC 2a).
Ribonuclease P (RNase P) catalyzes the 5′
maturation of precursor tRNA transcripts and, in bacteria,
is composed of a catalytic RNA and a protein. We investigated
the oligomerization state and the shape of the RNA alone
and the holoenzyme of Bacillus subtilis RNase
P in the absence of substrate by synchrotron small-angle
X-ray scattering and affinity retention. The B. subtilis
RNase P RNA alone is a monomer; however, the scattering
profile changes upon the addition of monovalent ions, possibly
suggesting different interdomain angles. To our surprise,
the X-ray scattering data combined with the affinity retention
results indicate that the holoenzyme contains two RNase
P RNA and two RNase P protein molecules. We propose a structural
model of the holoenzyme with a symmetrical arrangement
of the two RNA subunits, consistent with the X-ray scattering
results. This (P RNA)2(P protein)2
complex likely binds substrate differently than the conventional
(P RNA)1(P protein)1 complex; therefore,
the function of the B. subtilis RNase P holoenzyme
may be more diverse than previously thought. These revisions
to our knowledge of the RNase P holoenzyme suggest a more
versatile role for proteins in ribonucleoprotein complexes.
Three gibbon species inhabit the tropical and subtropical forests in China, all of which occur in Yunnan Province: the crested gibbon Hylobates concolor, lar gibbon H. lar, and hoolock gibbon H. hoolock. As a result of deforestation and over-hunting, all three species are gravely endangered in China and may be on the verge of extinction; they are now considered to be the nation's rarest animals. A recent census and survey of crested gibbons in Yunnan Province, partly funded from FFPS's Oryx 100% Fund, revealed new information on the distribution, status and conservation of gibbons in China. The authors made recommendations for future conservation measures, and these are now being considered by the Chinese Academy of Sciences and the Chinese Government.
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