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Flexibility is one of the important mechanical performance parameters of stent. The flexibility of tapered stents, especially self-expanding tapered stents, remains unknown. In this study, we developed a new selfexpanding tapered stent for tapered arteries and performed a numerical investigation of stent flexibility by using finite element method. The effect of stent design parameters, including taper and link space width, on stent flexibility was studied. The flexibility of the proposed stent was also compared with that of traditional cylindrical stents. Results show that the tapered stent is more flexible than the traditional cylindrical stent. Furthermore, the flexibility of the tapered stent increases with increasing stent taper and stent link space width. The increase in the stent link space width can contribute to the reduction in the peak stress. Therefore, tapered stents with high link space width will improve the stent flexibility. This work provides useful information for improvement of stent design and clinical selection.
The aim of this study was to clarify effects of Clozapine and its metabolites on insulin resection and expression of glucose transporter 2 (GLUT2) located in cell membrane of isolated rat's islets.
The cells of isolated rat's islets were prepared by a modified collagenase digestion methods. At 5.5 mmol/L glucose, the cells of islets was treated with 1mmol/L clozapine, desmethyl-clozapine(DCLO), clozapine N-oxide(CNO), respectively, blank control group was also set.
1. After incubation 48h, the insulin in supernatant was assayed by radioimmunoassay.
2. The cells of isolated rat's islets in each group were detected GLUT2 mRNA level with RT-PCR and its protein expression with Western-blot.
1. Compared to control group, clozapine significantly inhibited insulin secretion (P=0.007< 0.01); DCLO has a tendency to inhibit insulin secretion after 48h of incubation, but no significant difference was found (P=0.154>0.05). There was no difference of insulin secretion between CNO group and the control group after 48h of incubation (P>0.05).
2. The mRNA and protein expression of GLUT2 located in cell membrane of slets: clozapine group was significantly lower than control group (P=0.017< 0.05, P=0.035< 0.05), DCLO group was also lower than control group, but no significant difference was found (P>0.05), and no significant difference between CNO group and control group (P>0.05).
Clozapine can inhibit GLUT2 expression of cells of islets, and then hamper glucose transport through cell membrane, which was one of mechanisms to explain the effect of clozapine on insulin secretion.
The aim of this study was to compare the clinical efficacy and the safety of venlafaxine and fluoxetine in the treatment of obsessive-compulsive disorder (OCD).
One hundred and Eight inpatients who met the Diagnostic and Statistical Manual of Mental Disorders, the Forth Edition(DSM-IV) for OCD were involved in this study. The subjects were randomly divided into venlafaxine group or fluoxetine group. Efficacy of venlafaxine and fluoxetine in treatment of OCD were assessed with Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and Clinical Global Impression-Severity(CGI-S), the side effects were evaluated with Treatment Emergent Symptom Scale (TESS).
The therapeutic efficacy in venlafaxine group was similar to that in fluoxetine (70.36%vs68.29%, P>0.05) after eight weeks’ therapy. The improve-rates of Y-BOCS after 2 weeks’ therapy of venlafaxine were significant higher than those of baseline, while the improve-rates of Y-BOCS after 4 weeks’ therapy of fluoxetine were significant higher than those of baseline(P< 0.05). The side effects of venlafaxine group were similar to fluoxetine group (P>0.05).
The results indicate that both venlafaxine and fluoxetine is effective in the treatment of OCD, but venlafaxine work faster than fluoxutine.
In Korean culture, co-sleeping of parents and children are quite common, which is different from the Western culture where solitary sleeping of children is preferred. In this study, we evaluate the sleep environment factors that effect on children sleep disorder, and parent's parenting stress and mental health.
Surveys were conducted to 115 participating parents of preschool children sleeping behaviour lecture. Seventy-one completed surveys were analyzed for the study. The mean age of target children was 53 ± 23 months. Parents’ mental health was evaluated by using several forms such as Insomnia Severity Index, Korean-Parenting Stress Index short form, and The Patient Health Questionnaire-9. Children's sleeping environment and quality were assessed by Child Sleep Habit Questionnaire and Sleep environment survey.
Pearson correlation analysis (P < 0.05) was conducted to evaluate the relationship between the sleep disorder of children, and the parent's parenting stress and mental health. Analyzing the data through the partial least square path modeling, co-sharing would have negative effect; bed-sharing could have negative effect on the depressing emotion of parents (P = 0.065). Solitary sleeping of children could have positive effect on parent's mental health (P < 0.01).
Preschool children's sleeping disorder occurs more often in co-sleeping children with parents than solitary sleeping children. Parents’ parenting stress is related to the parent's age and depression, further related to the children sleeping disorder and their sleep environment. Although, it is difficult to generalize the exact cause, evaluation and improvement of children's sleep environment would help to reduce the parent's parenting stress.
Disclosure of interest
The authors have not supplied their declaration of competing interest.
BMI z (BMIz) score based on the Centers for Disease Control and Prevention growth charts is widely used, but it is inaccurate above the 97th percentile. We explored the performance of alternative metrics based on the absolute distance or % distance of a child’s BMI from the median BMI for sex and age. We used longitudinal data from 5628 children who were first examined <12 years to compare the tracking of three BMI metrics: distance from median, % distance from median and % distance from median on a log scale. We also explored the effects of adjusting these metrics for age differences in the distribution of BMI. The intraclass correlation coefficient (ICC) was used to compare tracking of the metrics. Metrics based on % distance (whether on the original or log scale) yielded higher ICCs compared with distance from median. The ICCs of the age-adjusted metrics were higher than that of the unadjusted metrics, particularly among children who were (1) overweight or had obesity, (2) younger and (3) followed for >3 years. The ICCs of the age-adjusted metrics were also higher compared with that of BMIz among children who were overweight or obese. Unlike BMIz, these alternative metrics do not have an upper limit and can be used for assessing BMI in all children, even those with very high BMIs. The age-adjusted % from median (on a log or linear scale) works well for all ages, while unadjusted % from median is better limited to older children or short follow-up periods.
The gut is composed of a single layer of intestinal epithelial cells and plays important roles in the digestion and absorption of nutrients, immune and barrier functions and amino acid metabolism. Weaning stress impairs piglet intestinal epithelium structural and functional integrities, which results in reduced feed intake, growth rates and increased morbidity and mortality. Several measures are needed to maintain swine gut development and growth performance after weaning stress. A large body of evidence indicates that, in weaning piglets, glutamine, a functional amino acid, may improve growth performance and intestinal morphology, reduce oxidative damage, stimulate enterocyte proliferation, modulate cell survival and death and enhance intestinal paracellular permeability. This review focuses on the effects of glutamine on intestinal health in piglets. The aim is to provide evidentiary support for using glutamine as a feed additive to alleviate weaning stress.
The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
Co-receptor tropism has been identified to correlate with HIV-1 transmission and the disease progression in patients. A molecular epidemiology investigation of co-receptor tropism is important for clinical practice and effective control of HIV-1. In this study, we investigated the co-receptor tropism on HIV-1 variants of 85 antiretroviral-naive patients with Geno2pheno algorithm at a false-positive rate of 10%. Our data showed that a majority of the subjects harboured the CCR5-tropic virus (81.2%, 69/85). No significant differences in gender, age, baseline CD4+ T-cell counts and transmission routes were observed between subjects infected with CXCR4-tropic or CCR5-tropic virus. The co-receptor tropism appeared to be associated with the virus genotype; a significantly more CXCR4-use was predicted in CRF01_AE infections whereas all CRF07_BC and CRF08_BC were predicted to use CCR5 co-receptor. Sequences analysis of V3 revealed a higher median net charge in the CXCR4 viruses over CCR5 viruses (4.0 vs. 3.0, P < 0.05). The predicted N-linked glycosylation site between amino acids 6 and 8 in the V3 region was conserved in CCR5 viruses, but not in CXCR4 viruses. Besides, variable crown motifs were observed in both CCR5 and CXCR4 viruses, of which the most prevalent motif GPGQ existed in both viral tropism and almost all genotypes identified in this study except subtype B. These findings may offer important implications for clinical practice and enhance our understanding of HIV-1 biology.
Recent experiments on thin films flowing down a vertical fibre with varying nozzle diameters present a wealth of new dynamics that illustrate the need for more advanced theory. We present a detailed analysis using a full lubrication model that includes slip boundary conditions, nonlinear curvature terms and a film stabilization term. This study brings to focus the presence of a stable liquid layer playing an important role in the full dynamics. We propose a combination of these physical effects to explain the observed velocity and stability of travelling droplets in the experiments and their transition to isolated droplets. This is also supported by stability analysis of the travelling wave solution of the model.
Although application of organic fertilizers has become a recommended way for developing sustainable agriculture, it is still unclear whether above-ground and below-ground crops have similar responses to chemical fertilizers (CF) and organic manure (OM) under the same farming conditions. The current study investigated soil quality and crop yield response to fertilization of a double-cropping system with rapeseed (above-ground) and sweet potato (below-ground) in an infertile red soil for 2 years (2014–16). Three fertilizer treatments were compared, including CF, OM and organic manure plus chemical fertilizer (MCF). Organic fertilizers (OM and MCF) increased the yield of both above- and below-ground crops and improved soil biochemical properties significantly. The current study also found that soil-chemical properties were the most important and direct factors in increasing crop yields. Also, crop yield was affected indirectly by soil-biological properties, because no significant effects of soil-biological activities on yield were detected after controlling the positive effects of soil-chemical properties. Since organic fertilizers could not only increase crop yield, but also improve soil nutrients and microbial activities efficiently and continuously, OM application is a reliable agricultural practice for both above- and below-ground crops in the red soils of China.
To investigate whether amnestic mild cognitive impairment (aMCI) identified with visual memory tests conveys an increased risk of Alzheimer’s disease (risk-AD) and if the risk-AD differs from that associated with aMCI based on verbal memory tests.
4,771 participants aged 70.76 (SD = 6.74, 45.4% females) from five community-based studies, each a member of the international COSMIC consortium and from a different country, were classified as having normal cognition (NC) or one of visual, verbal, or combined (visual and verbal) aMCI using international criteria and followed for an average of 2.48 years. Hazard ratios (HR) and individual patient data (IPD) meta-analysis analyzed the risk-AD with age, sex, education, single/multiple domain aMCI, and Mini-Mental State Examination (MMSE) scores as covariates.
All aMCI groups (n = 760) had a greater risk-AD than NC (n = 4,011; HR range = 3.66 – 9.25). The risk-AD was not different between visual (n = 208, 17 converters) and verbal aMCI (n = 449, 29 converters, HR = 1.70, 95%CI: 0.88, 3.27, p = 0.111). Combined aMCI (n = 103, 12 converters, HR = 2.34, 95%CI: 1.13, 4.84, p = 0.023) had a higher risk-AD than verbal aMCI. Age and MMSE scores were related to the risk-AD. The IPD meta-analyses replicated these results, though with slightly lower HR estimates (HR range = 3.68, 7.43) for aMCI vs. NC.
Although verbal aMCI was most common, a significant proportion of participants had visual-only or combined visual and verbal aMCI. Compared with verbal aMCI, the risk-AD was the same for visual aMCI and higher for combined aMCI. Our results highlight the importance of including both verbal and visual memory tests in neuropsychological assessments to more reliably identify aMCI.
Vessel flexure can be triggered naturally by surgical operation, heart pulsation and body movement. It may affect the mechanical behavior of the stent and the existence of a stent may in turn cause vessel injury. In the present study, the finite element method is employed to study the interaction between stent and vessel during vessel flexure. Two- and four-link stents made of stainless steel 316L and magnesium alloy WE43 are considered. Results indicate that longitudinal deformation of the stent can be caused by vessel flexure, and the higher levels of stress exist in the link struts. The existence of the stent could induce significant stress concentration and straightened deformation on vessel wall in the course of vessel flexure. Stents with more links or made of harder materials show greater anti-deformation capability, thus inducing a more severe stress concentration and straightened deformation on the vessel wall. The bending direction also affects the mechanical performance of the vessel-stent system. The results obtained could provide useful information for better stent designs and clinical decisions.
Phenoloxidase (PO) plays a key role in melanin biosynthesis during insect development. Here, we isolated the 2310-bp full-length cDNA of PPO1 from Zeugodacus tau, a destructive horticultural pest. qRT-polymerase chain reaction showed that the ZtPPO1 transcripts were highly expressed during larval–prepupal transition and in the haemolymph. When the larvae were fed a 1.66% kojic acid (KA)-containing diet, the levels of the ZtPPO1 transcripts significantly increased by 2.79- and 3.39-fold in the whole larvae and cuticles, respectively, while the corresponding PO activity was significantly reduced; in addition, the larval and pupal durations were significantly prolonged; pupal weights were lowered; and abnormal phenotypes were observed. An in vitro inhibition experiment indicated that KA was an effective competitive inhibitor of PO in Z. tau. Additionally, the functional analysis showed that 20E could significantly up-regulate the expression of ZtPPO1, induce lower pupal weight, and advance pupation. Knockdown of the ZtPPO1 gene by RNAi significantly decreased mRNA levels after 24 h and led to low pupation rates and incomplete pupae with abnormal phenotypes during the larval-pupal interim period. These results proved that PO is important for the normal growth of Z. tau and that KA can disrupt the development of this pest insect.
Introduction: ex-specific diagnostic cutoffs may improve the test characteristics of high-sensitivity troponin assays for the diagnosis of myocardial infarction. Sex-specific cutoffs for ruling in MI improve the sensitivity of the assay for MI among women, and improve the specificity of diagnosis among men. We hypothesized that the use of sex-specific high-sensitivity Troponin T (hsTnT) cutoffs for ruling out MI at the time of ED arrival would improve the classification efficiency of the assay by enabling more patients to have MI ruled out at the time of ED arrival while maintaining diagnostic sensitivity. The objective of this study was to quantify the test characteristics of sex-specific cutoffs of an hsTnT assay for acute myocardial infarction (AMI) when performed at ED arrival in patients with chest pain. Methods: This retrospective study included consecutive ED patients with suspected cardiac chest pain evaluated in four urban EDs were, excluding those with ST-elevation AMI, cardiac arrest or abnormal kidney function. The primary outcomes was AMI at 7 days. Secondary outcomes included major adverse cardiac events (MACE: all-cause mortality, AMI and revascularization) and the individual MACE components. We quantified test characteristics (sensitivity, negative predictive value, likelihood ratios and proportion of patients ruled out) for multiple combinations of sex-specific rule-out cutoffs. We calculated net reclassification improvement compared to universal rule-out cutoffs of 5ng/L (the assays limit of detection) and 6ng/L (the FDA-approved limit of quantitation for US laboratories). Results: 7130 patients, including 3931 men and 3199 women, were included. The 7-day incidence of AMI was 7.38% among men and 3.78% among women. Universal cutoffs of 5 and 6 ng/L ruled out AMI with 99.7% sensitivity in 33.6 and 42.2% of patients. The best-performing combination of sex-specific cutoffs (8g/L for men and 6ng/L for men) ruled out AMI with 98.7% sensitivity in 51.9% of patients. Conclusion: Sex-specific hsTnT cutoffs for ruling out AMI at ED arrival may achieve substantial improvement in classification performance, enabling more patients to be ruled out at ED arrival, while maintaining acceptable diagnostic sensitivity for AMI. Universal and sex-specific rule-out cutoffs differ by only small changes in hsTnT concentration. Therefore, these findings should be confirmed in other datasets.
Introduction: Patients with chronic kidney disease (CKD) are at high risk of cardiovascular events, and have worse outcomes following acute myocardial infarction (AMI). Cardiac troponin is often elevated in CKD, making the diagnosis of AMI challenging in this population. We sought to quantify test characteristics for AMI of a high-sensitivity troponin T (hsTnT) assay performed at emergency department (ED) arrival in CKD patients with chest pain, and to derive rule-out cutoffs specific to patient subgroups stratified by estimated glomerular filtration rate (eGFR). We also quantified the sensitivity and classification performance of the assays limit of detection (5 ng/L) and the FDA-approved limit of quantitation (6 ng/L) for ruling out AMI at ED arrival. Methods: Consecutive patients in four urban EDs from the 2013 calendar year with suspected cardiac chest pain who had a Roche Elecsys hsTnT assay performed on arrival were included f. This analysis was restricted to patients with an eGFR< 60 ml/min/1.73m2. The primary outcome was 7-day AMI. Secondary outcomes included major adverse cardiac events (death, AMI and revascularization). Test characteristics were calculated and ROC curves were generated for eGFR subgroups. Results: 1416 patients were included. 7-day AMI incidence was 10.1%. 73% of patients had an initial hsTnT concentration greater than the assays 99th percentile (14 ng/L). TCurrently accepted cutoffs to rule out MI at ED arrival ( 5 ng/L and 6 ng/L) had 100% sensitivity for AMI, but no patients with an eGFR less than 30 ml/min/1.73M had hsTnT concentrations below these thresholds. We derived eGFR-adjusted cutoffs to rule out MI with sensitivity >98% at ED arrival, which were able to rule out 6-42% of patients, depending on eGFR category. The proportion of patients able to be accurately ruled-in with a single hsTnT assay was substantially lower among patients with an eGFR <30 ml/min/1.73m2 (6-20% vs 25-43%). We also derived eGFR-adjusted cutoffs to rule-in AMI with specificity >90%, which accurately ruled-in up to 18% of patients. Conclusion: Cutoffs achieving acceptable diagnostic performance for AMI using single hsTnT sampling on ED arrival may have limited clinical utility, particularly among patients with very low eGFR. The ideal diagnostic strategy for AMI in patients with CKD likely involves serial high-sensitivity troponin testing with diagnostic thresholds customized to different eGFR categories.
Plant height and lodging resistance can affect rice yield significantly, but these traits have always conflicted in crop cultivation and breeding. The current study aimed to establish a rapid and accurate plant type evaluation mechanism to provide a basis for breeding tall but lodging-resistant super rice varieties. A comprehensive approach integrating plant anatomy and histochemistry was used to investigate variations in flexural strength (a material property, defined as the stress in a material just before it yields in a flexure test) of the rice stem and the lodging index of 15 rice accessions at different growth stages to understand trends in these parameters and the potential factors influencing them. Rice stem anatomical structure was observed and the lignin content the cell wall was determined at different developmental stages. Three rice lodging evaluation models were established using correlation analysis, multivariate regression and artificial radial basis function (RBF) neural network analysis, and the results were compared to identify the most suitable model for predicting optimal rice plant types. Among the three evaluation methods, the mean residual and relative prediction errors were lowest using the RBF network, indicating that it was highly accurate and robust and could be used to establish a mathematical model of the morphological characteristics and lodging resistance of rice to identify optimal varieties.
Whether monozygotic (MZ) and dizygotic (DZ) twins differ from each other in a variety of phenotypes is important for genetic twin modeling and for inferences made from twin studies in general. We analyzed whether there were differences in individual, maternal and paternal education between MZ and DZ twins in a large pooled dataset. Information was gathered on individual education for 218,362 adult twins from 27 twin cohorts (53% females; 39% MZ twins), and on maternal and paternal education for 147,315 and 143,056 twins respectively, from 28 twin cohorts (52% females; 38% MZ twins). Together, we had information on individual or parental education from 42 twin cohorts representing 19 countries. The original education classifications were transformed to education years and analyzed using linear regression models. Overall, MZ males had 0.26 (95% CI [0.21, 0.31]) years and MZ females 0.17 (95% CI [0.12, 0.21]) years longer education than DZ twins. The zygosity difference became smaller in more recent birth cohorts for both males and females. Parental education was somewhat longer for fathers of DZ twins in cohorts born in 1990–1999 (0.16 years, 95% CI [0.08, 0.25]) and 2000 or later (0.11 years, 95% CI [0.00, 0.22]), compared with fathers of MZ twins. The results show that the years of both individual and parental education are largely similar in MZ and DZ twins. We suggest that the socio-economic differences between MZ and DZ twins are so small that inferences based upon genetic modeling of twin data are not affected.
The Universe is permeated by hot, turbulent, magnetized plasmas. Turbulent plasma is a major constituent of active galactic nuclei, supernova remnants, the intergalactic and interstellar medium, the solar corona, the solar wind and the Earth’s magnetosphere, just to mention a few examples. Energy dissipation of turbulent fluctuations plays a key role in plasma heating and energization, yet we still do not understand the underlying physical mechanisms involved. THOR is a mission designed to answer the questions of how turbulent plasma is heated and particles accelerated, how the dissipated energy is partitioned and how dissipation operates in different regimes of turbulence. THOR is a single-spacecraft mission with an orbit tuned to maximize data return from regions in near-Earth space – magnetosheath, shock, foreshock and pristine solar wind – featuring different kinds of turbulence. Here we summarize the THOR proposal submitted on 15 January 2015 to the ‘Call for a Medium-size mission opportunity in ESAs Science Programme for a launch in 2025 (M4)’. THOR has been selected by European Space Agency (ESA) for the study phase.