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Synaptotagmin 1 (Syt1) is an abundant and important presynaptic vesicle protein that binds Ca2+ for the regulation of synaptic vesicle exocytosis. Our previous study reported its localization and function on spindle assembly in mouse oocyte meiotic maturation. The present study was designed to investigate the function of Syt1 during mouse oocyte activation and subsequent cortical granule exocytosis (CGE) using confocal microscopy, morpholinol-based knockdown and time-lapse live cell imaging. By employing live cell imaging, we first studied the dynamic process of CGE and calculated the time interval between [Ca2+]i rise and CGE after oocyte activation. We further showed that Syt1 was co-localized to cortical granules (CGs) at the oocyte cortex. After oocyte activation with SrCl2, the Syt1 distribution pattern was altered significantly, similar to the changes seen for the CGs. Knockdown of Syt1 inhibited [Ca2+]i oscillations, disrupted the F-actin distribution pattern and delayed the time of cortical reaction. In summary, as a synaptic vesicle protein and calcium sensor for exocytosis, Syt1 acts as an essential regulator in mouse oocyte activation events including the generation of Ca2+ signals and CGE.
One of the critical prerequisites for accurately measuring the mechanical properties of profiled fibers is the precise determination of their cross-sectional areas (CSAs). In this study, a new method is established for determining a single profiled fibers’ CSA based on the frozen section method and digital photo, pixel-ratio method (FS-DP). FS-DP is used to obtain a transverse section of a fiber, by acquiring an image of the cross section using optical microscopy or scanning electron microscopy, and then calculating the CSA using Photoshop. Using FS-DP, it was found that the shape of a fiber of silk changes little in a range of 50 μm, but varies considerably over a range of 1 m, while the CSA of cocoon silk (900 m) first increases and then decreases. Mechanical property tests showed that the elongation, strength, elastic modulus, and toughness values of the cocoon silk are consistent with those reported previously. Additionally, FS-DP was also used to observe other profiled fibers. The application tests indicated that FS-DP can be used to quickly and accurately obtain the CSA of a single profiled fiber, and that it is suitable for the large-scale determination and analysis of the mechanical properties of profiled fibers.
Apathy is a condition characterized by a lack of motivation that manifests in emotional, behavioral, and cognitive domains. Although previous studies have indicated that apathy is associated with frontal lesions, few studies have focused on the different subdomains of apathy, and no in vivo human biochemical data have been obtained to examine the neurochemical changes related to apathy in patients with Alzheimer's disease (AD). Thus, we investigated the frontal neurochemical alterations related to apathy among patients with AD using proton magnetic resonance spectroscopy (1H MRS).
Apathy was assessed through the Apathy Evaluation Scale (AES). 1H MRS was performed to measure neurochemical metabolite levels in the anterior cingulate region and right orbitofrontal region. Associations between neurochemical metabolites and the total score and subscores of each domain of the AES were analyzed.
Altogether, 36 patients completed the study. Patients with lower N-acetylaspartate/creatine ratios (NAA/Cr) in the anterior cingulate region demonstrated higher total apathy scores (β = −0.56, p = 0.003) with adjustments for age, gender, educational level, dementia severity, and depression severity. In a further analysis, a lower NAA/Cr in the anterior cingulate region was associated with all subdomains of apathy, including cognition (β = −0.43, p = 0.028), behavior (β = −0.55, p = 0.002), and emotion (β = −0.50, p = 0.005). No statistically significant associations were discovered in the right orbitofrontal region.
Our results suggest that apathy, in each of its cognitive, behavioral, or emotional subdomains is associated with brain neurochemical alterations in the anterior cingulate region. Abnormal neuronal integrity over the anterior cingulate cortex may exhibit a central role in causing all aspects of apathy in patients with AD.
A series of self-assembled WO3–BiVO4 nanostructured thin films with 17, 25, 50, 67, and 100 mol% WO3 were grown on the (001) yttria-stabilized zirconia (YSZ) substrate by pulsed laser deposition method. The microstructures including crystalline phases, epitaxial relationship, interface structures, and chemical composition distributions were investigated by a combination of various electron microscopy techniques including scanning electron microscopy, transmission electron microscopy, and X-ray energy dispersive spectroscopy. The monoclinic BiVO4 formed the matrix, in which WO3 nanopillars were embedded with specific epitaxial relationships. In BiVO4-rich sample, orthorhombic Bi2WO6 was formed. However, metastable hexagonal WO3 phase and orthorhombic WO3 phase coexisted in other composite samples. The thin amorphous layer at the film/substrate interface indicated that the mismatch strain between films and substrate is released. The hydrostatic tensile strain due to thermal expansion mismatch between BiVO4 and WO3 as well as the diffusion of Bi into the WO3 stabilized the metastable h-WO3. A WO3–BiVO4 pseudobinary phase diagram was proposed based on the magnitude of the thermal expansion mismatch and the distance of Bi diffusion, which can be applied to design the microstructures of WO3–BiVO4 heterojunctions and optimize their photoelectrochemical properties.
The prevalence of CHD has been well described worldwide except in Tibet. This study aimed to illustrate the prevalence and composition of CHD in Tibetan children according to altitude.
Methods and results
In the first part, we prospectively recruited 7088 unselected Tibetan children (4–17 years) from south-west Tibet. The total prevalence of CHD increased from 4.6/1000 below 4200 m to 13.4/1000 above 4700 m, with a female-to-male ratio of 1.3:3.1. The total prevalence and female prevalence of patent ductus arteriosus increased more than 10-fold. Females living above 4700 m had exceptionally high prevalence of patent ductus arteriosus (14.9/1000). The prevalence of atrial septal defect was comparable among different altitudes (3.3–3.8/1000). The prevalence of ventricular septal defect was 1.3/1000 below 4700 m, and no cases were found above this altitude. In the second part, we retrospectively reviewed the clinical data of 383 CHD children in Tibet and 73 children at lower altitudes. The percentage of isolated ventricular septal defect decreased from 54.8 to 3.1%, and the percentage of isolated patent ductus arteriosus increased from 8.2 to 68.4% with elevation. Children living below 4200 m (10.4–13.7%) had a larger proportion of complex CHD than those above this altitude (2.0–3.1%). Of the 20 Tibetan children with complex CHD, 14 (70.0%) lived below 4200 m.
A wide variation in CHD prevalence and composition existed in Tibetan children among different altitudes.
Hepatocellular carcinoma (HCC) is a primary liver malignancy that mainly occurs in patients with chronic liver disease and cirrhosis. Risk factors for HCC include hepatitis B virus (HBV) infection. However, the specific role of HBV infection in HCC development is not yet completely understood. In order to reveal the effects of HBV on HCC, we compare the genes of HCC patients infected with HBV with those who are not infected.
We encoded the genes of these two types of HCC in databases using enrichment scores of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway terms. A random forest algorithm was employed in order to distinguish these two types in the classifier, and a series of feature selection approaches was used in order to select their optimal features. Novel HBV-associated and -non-associated HCC genes were predicted, respectively, based on their optimal features in the classifier. A shortest-path algorithm was also employed in order to find all of the shortest-paths genes connecting the known related genes.
A total of 54 different features between HBV-associated and -non-associated HCC genes were identified. In total, 1236 and 881 novel related genes were predicted for HBV-associated and -non-associated HCC, respectively. By integrating the predicted genes and shortest path genes in their gene interaction network, we identified 679 common genes involved in the two types of HCC.
We identified the significantly different genetic features between two types of HCC. We also predicted related genes for the two types based on their specific features. Finally, we determined the common genes and features that were involved in both of these two types of HCC.
Introduction: The mortality of Parkinson’s disease (PD) and its associated risk factors among clinically definite PD patients in China has been rarely investigated. Our study aimed to identify the mortality rates and predictors of death in PD patients in China. Methods: 157 consecutive, clinically definite PD patients from the urban area of Shanghai were recruited from a central hospital based movement disorder clinic in 2006. All patients were regularly followed up at the clinic until December 31, 2011, or death. Mortality and associations with baseline demographics, health and medical factors were then determined within the cohort. Results: After 5 years, 11(7%) patients had died. The standardised mortality ratio was 0.62 (95% CI 0.32 to 1.07, P=0.104). The main causes of death were pneumonia (54.5%, 6/11) and digestive disorders (18.2%, 2/11), respectively. Age at onset, independent living, the mini mental state examination score, the Parkinson’s disease sleep scale score and the Epworth sleepiness scale score at baseline were statistically significantly different between the survival group and the deceased group (P<0.05). Across all participants, risk factors for death included low mini mental state examination score, and high Epworth sleepiness scale score according to a binary variable logistic regression analysis. Conclusions: This study confirms the similar survival of patients with PD to the control population up to a follow-up of 5 years. Interventions tailored to potential risk factors associated with death may offer further benefits.
We aim to investigate the formation of sub-galactic structure in the Lambda cold dark matter (CDM) cosmology. To accomplish our research goal, we have added various baryonic physics on the existing cosmological hydrodynamic code, GADGET-2. We performed two test runs to check our new implementations. We show our preliminary results from these test runs.
This paper discusses the effectiveness of hydroxyapatite (HAP) as an inorganic consolidant for physically weathered Indiana Limestone, and as a coupling agent between limestone and a silicate consolidant. A double application is investigated, in which samples are coated with HAP followed by a commercially available silicate-based consolidant (Conservare® OH-100). To artificially weather limestone, a thermal degradation technique was utilized. Diammonium hydrogen phosphate (DAP) salt was reacted with limestone, alone and with cationic precursors, to produce HAP films. The dynamic elastic modulus, water sorptivity and tensile strength of the treated stones were evaluated. HAP was found to be an effective consolidant for weathered Indiana Limestone, and its performance was enhanced by addition of millimolar quantities of calcium chloride. However, HAP was not useful as a coupling agent; a double treatment with DAP is more effective than sequential treatment with DAP and Conservare®.
Unawareness of deficits is common and is associated with poor outcomes in Alzheimer's disease (AD); however, little is known about correlated neurobiochemical changes.
Proton magnetic resonance spectroscopy was used to examine neurobiochemical correlates of unawareness of deficits as assessed by the Dementia Deficit Scale in 36 patients with AD. Magnetic resonance spectroscopy spectra were acquired from the anterior cingulate area and right orbitofrontal area. Concentrations of N-acetyl-aspartate (NAA), total creatine, and other neurometabolites were calculated.
Nineteen (52.8%) participants had relative unawareness of deficits. This condition was negatively correlated with NAA/creatine in the anterior cingulate area (β = −0.36, p = 0.025) and positively correlated with NAA/creatine in the right orbitofrontal area (β = 0.41, p = 0.009) after controlling for dementia severity.
These findings suggest unawareness of deficits in AD was associated with the altered neurochemical metabolites in the anterior cingulate area and right orbitofrontal area. However, the two areas might have opposite neuronal functions in unawareness of deficits.
A thalattosaur taxon, Concavispina biseridens, was recently named and briefly described. It is described here in detail and compared with other thalattosaurs, especially Xinpusaurus. Concavispina is characterized by a long skull, measuring approximately half the length of presacral portion of the vertebral column, two rows of blunt teeth on the anterior part of the maxilla, and neural spines that have convex anterior or posterior margins and V-shaped notches in their dorsal margins. Concavispina differs from all thalattosaurs except Xinpusaurus in that the anterior end of the maxilla is curved dorsally, less than five cervical vertebrae are present, and the proximal end of the humerus is wider than the distal end. Phylogenetic analysis of 40 characters suggests that Miodentosaurus occupies a basal position within Askeptosauridea, Paralonectes is the basalmost member of Thalattosauridea, Concavispina may form a clade with Xinpusaurus, and Chinese thalattosaurs do not have a close relationship with eastern Pacific forms as suggested by previous studies. Concavispina may have been similar to Xinpusaurus in overall locomotor style, but probably had a poorer swimming ability. Concavispina likely differed from Xinpusaurus in diet, for example by depending on softer food.
We report high-precision measurements of the Nusselt number as a function of the Rayleigh number in water-filled rectangular Rayleigh–Bénard convection cells. The horizontal length and width of the cells are 50.0 and 15.0 cm, respectively, and the heights , 25.0, 12.5, 6.9, 3.5, and 2.4 cm, corresponding to the aspect ratios , , , , , and . The measurements were carried out over the Rayleigh number range and the Prandtl number range . Our results show that for rectangular geometry turbulent heat transport is independent of the cells’ aspect ratios and hence is insensitive to the nature and structures of the large-scale mean flows of the system. This is slightly different from the observations in cylindrical cells where is found to be in general a decreasing function of , at least for and larger. Such a difference is probably a manifestation of the finite plate conductivity effect. Corrections for the influence of the finite conductivity of the top and bottom plates are made to obtain the estimates of for plates with perfect conductivity. The local scaling exponents of are calculated and found to increase from 0.243 at to 0.327 at .
Penaeus monodon (mean initial wet weight 1·19 (se 0·01) g) were fed seven diets in triplicate: a control diet (D1) without carotenoids; three diets formulated to supply 0·1 % astaxanthin alone (D2), 0·2 % astaxanthin alone (D3), and a combination of 0·1 % astaxanthin and 1 % cholesterol (D4); three diets with 0·07 % canthaxanthin alone (D5), 0·13 % canthaxanthin alone (D6), and a combination of 0·07 % canthaxanthin and 1 % cholesterol (D7). Weight gain (WG, %), specific growth rate (SGR, %/d) and survival were chosen as parameters of shrimp growth performance. Total antioxidant status (TAS), superoxide dismutase (SOD), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were chosen as indices of shrimp plasma antioxidant capacity. Meanwhile, digestibility, retention efficiency and tissue carotenoids were also investigated to determine the additive effect of cholesterol on the efficiency of astaxanthin and canthaxanthin. After 74 d rearing, WG and SGR of shrimp fed D2–D4 and D7 were higher than those of shrimp fed D1 (P < 0·05). Shrimp fed D4 had the highest survival. The apparent digestibility coefficients (ADC) of astaxanthin in D2–D4 were higher than those of canthaxanthin in D5–D7 (P < 0·05). Although ADC of astaxanthin were quite high (>98 %) in D2–D4 and no differences were found among them (P>0·05), the carotenoid retention efficiencies in the whole body, muscle and shell (D2–D3 treatments) were considerably low; however, cholesterol supplementation significantly improved the carotenoid retention efficiencies in the whole body, muscle and shell (D4 treatment). Accordingly, the addition of cholesterol also significantly enhanced the carotenoid contents of tissues. Shrimp fed supplemented carotenoid diets (D2–D7) had higher TAS and lower SOD, ALT and AST than shrimp fed D1 (P < 0·05). A low dissolved oxygen stress test was conducted for 7 d after the rearing trial and shrimp survival was also compared among the treatments. The survival of shrimp fed the diets supplemented with astaxanthin or canthaxanthin was higher than that of shrimp fed D1 during the stress test (P < 0·05). In conclusion, all data suggested that astaxanthin was better than canthaxanthin as the dietary carotenoid source in the commercial diet of P. monodon, and the supplement of cholesterol could positively enhance the efficiency of astaxanthin and canthaxanthin.
There are close links among hyperglycaemia, oxidative stress and diabetic complications. Glutamine (GLN) is an amino acid with immunomodulatory properties. The present study investigated the effect of dietary GLN on oxidative stress-relative gene expressions and tissue oxidative damage in diabetes. There were one normal control (NC) and two diabetic groups in the present study. Diabetes was induced by an intraperitoneal injection of nicotinamide followed by streptozotocin (STZ). Rats in the NC group were fed a regular chow diet. In the two diabetic groups, one group (diabetes mellitus, DM) was fed a common semi-purified diet while the other group received a diet in which part of the casein was replaced by GLN (DM-GLN). GLN provided 25 % of total amino acid N. The experimental groups were fed the respective diets for 8 weeks, and then the rats were killed for further analysis. The results showed that blood thioredoxin-interacting protein (Txnip) mRNA expression in the diabetic groups was higher than that in the NC group. Compared with the DM group, the DM-GLN group had lower glutamine fructose-6-phosphate transaminase 1, a receptor of advanced glycation end products, and Txnip gene expressions in blood mononuclear cells. The total antioxidant capacity was lower and antioxidant enzyme activities were altered by the diabetic condition. GLN supplementation increased antioxidant capacity and normalised antioxidant enzyme activities. Also, the renal nitrotyrosine level and Txnip mRNA expression were lower when GLN was administered. These results suggest that dietary GLN supplementation decreases oxidative stress-related gene expression, increases the antioxidant potential and may consequently attenuate renal oxidative damage in rats with STZ-induced diabetes.
We report an experimental investigation of the longitudinal space–time cross-correlation function of the velocity field, , in a cylindrical turbulent Rayleigh–Bénard convection cell using the particle image velocimetry (PIV) technique. We show that while Taylor’s frozen-flow hypothesis does not hold in turbulent thermal convection, the recent elliptic model advanced for turbulent shear flows (He & Zhang, Phys. Rev. E, vol. 73, 055303) is valid for the present velocity field for all over the cell, i.e. the isocorrelation contours of the measured have an elliptical curve shape and hence can be related to via with and being two characteristic velocities. We further show that the fitted is proportional to the mean velocity of the flow, but the values of are larger than the theoretical predictions. Specifically, we focus on two representative regions in the cell: the region near the cell sidewall and the cell’s central region. It is found that and are approximately the same near the sidewall, while at the cell centre.
The two major lineages of extant archosaurs, crocodylians and avians, diverged in the Triassic, but the details and timing of this event are incompletely understood. Fragmentary and phylogenetically uninformative specimens, in addition to poor temporal constraints on rock units from the Early and Middle Triassic, typify obstacles in identifying early archosaurs. This paper re-describes the partial skeleton of the only known specimen of Xilousuchus sapingensis Wu, 1981 from the Early Triassic Heshanggou Formation in north-central China. Originally assigned to the non-archosaurian archosauriform clade Proterosuchidae, an extensive phylogenetic analysis posits X. sapingensis as a crown-group archosaur within Suchia, thus making this taxon the unequivocally oldest known member of Archosauria. The age and phylogenetic position of X. sapingensis indicate that many archosaurs, including all major clades of non-archosaurian archosauriforms, the avianline, ornithosuchids, aetosaurs and paracrocodylomorph lineages, must have diverged by the end of the Early Triassic. X. sapingensis is part of a possible clade of sail-backed poposauroids that were common components of archosaur assemblages during the Early to Middle Triassic.
Prophylaxis and treatment with oseltamivir effectively controlled a community outbreak of pandemic influenza A (H1N1) in China. The genetic makeup of strains of different generations seemed to be stable. Travel in confined settings might accelerate the transmission of pandemic influenza in a community outbreak.
In this study, the influence of T5 heat treatment on tensile and fatigue behavior of hot-extruded Mg–10Gd–3Y (wt%) magnesium alloy has been investigated. High cycle fatigue tests were carried out at a stress rate (R) of −1 and a frequency of 100 Hz using hour-glass-shaped round specimens with a gauge diameter of 5.8 mm. The results show that fatigue strength (at 107 cycles) of Mg–10Gd–3Y magnesium alloy increases from 150 to 165 MPa after T5 heat treatment, i.e., the improvement of 10% in fatigue strength has been achieved. However, the crack growth resistance is lowered by T5 heat treatment. Results of microstructure observation and scanning electron microscopy-energy dispersive x-ray (SEM-EDX) analysis suggest that the fatigue strength in the Mg–10Gd–3Y magnesium alloy is determined by the threshold stress of basal slip, which is induced by solid solution hardening and precipitation hardening.
In this paper, using a scalarization method, we obtain sufficient conditions for the lower semicontinuity and continuity of the solution mapping to a parametric generalized weak vector equilibrium problem with set-valued mappings.
Six transgenic maize lines with the fully modified gene GFM Cry1A were obtained and polymerase chain reaction (PCR) analysis of their T5 generation plants indicated that foreign genes could be stably inherited. Three hybrids (Simi25Bt, Tongdan24Bt and Jidan209Bt) were created using the transgenic lines and combined with regular maize inbred lines. The results of resistance identification of the transgenic inbred lines and hybrids showed that the difference of resistance among transgenic lines was very significant; there also existed a difference among individuals of the same line and among the three hybrids. Compared with the control inbred line (CK), the average of four transgenic inbred lines in the number of tunnels per stalk, larval tunnel length per plant and length of surviving larvae were decreased by 70%, 80% and 70%, respectively. Enzyme-linked immunosorbent assay (ELISA) testing showed that the average of Bt Cry1A protein expression level for six transgenic inbred lines was 0.16% total protein and the highest expression level was 0.19%. At maturity, compared with the control variety (CK), the larval tunnel length per plant of the three hybrids (Simi25Bt, Tongdan24Bt and Jidan209Bt) was decreased by 39.97%, 36.20% and 53.83%, respectively, which was a decrease of 43.36% on average. The investigation of agronomic characters showed that there was no significant difference between the improved hybrids and the control in plant height, ear length, row number per ear, kernel number per row and 100-kernels weight. It is thought that the GFM Cry1A gene can be applied to improve resistance to corn-borer, and maize inbred lines with the Bt gene can be directly applied to conventional maize breeding.