[Stress distribution and deformation of uterosacral ligament and cardinal ligament under different working conditions simulated by the finite element model]

OBJECTIVE

To establish the finite element model of uterosacral ligament (USL) and cardinal ligament (CL) and analyze the stress distribution and deformation with USL and CL under different working conditions.

METHODS

Patients with stage Ⅲ-Ⅳ pelvic organ prolapse (POP) and healthy female volunteers were selected for research subject, and divided into anterior uterus group and posterior uterus group. Two POP patients and two volunteers were selectd into the anterior uterus group and posterior uterine group respectively. Pelvic MRI scan was performed in two groups. Based on the original MRI data sets, the finite element model of USL and CL was constructed by using the software such as the Mimics, and the stress distribution and deformation of USL and CL were simulated.

RESULTS

Under the premise of the elastic modulus fixed and three different working conditions such as 60 cmH2O, 99 cmH2O and 168 cmH2O (1 cmH2O=0.098 kPa) with abdominal pressure generated by maximum Valsalva maneuver, according to the present conditions and the simulation, the trend was analyzed: the stress and deformation of the uterus, anterior vaginal wall, USL and CL in two groups were mainly distributed in the middle and lower part of the anterior vaginal wall or the ligament and the cervix-vagina junction, the maximum stress and the maximum displacement were mainly concentrated in the lower region of the anterior vaginal wall. With increasing of abdominal pressure generated by the maximum Valsalva maneuver, the maximum stress values of the POP patient in anterior uterus group under three different working conditions were: 0.027 9, 0.046 0, 0.078 0 MPa, and the maximum displacement values were: 9.145 5, 15.090 0, 25.607 0 mm. The maximum stress values of the volunteer in anterior uterus group under three different working conditions were: 0.012 6, 0.020 8, 0.035 3 MPa, and the maximum displacement values were: 1.816 7, 2.997 5, 5.086 7 mm. The maximum stress values of the POP patient in posterior uterine group under three different conditions were: 0.069 4, 0.114 6, 0.194 5 MPa, and the maximum displacement values were: 11.658 0, 19.236 0, 32.643 0 mm. The maximum stress values of the volunteer in posterior uterus group under three different working conditions were: 0.009 1, 0.015 1, 0.025 6 MPa, and the maximum displacement values were: 2.581 6, 4.259 6, 7.228 4 mm. The maximum stress values and the maximum displacement values were all increased with increasing of abdominal pressure in the two groups. The maximum stress values and the maximum displacement values of the POP patients were greater than those of volunteers. Under different working conditions, the maximum stress values and maximum displacement values of the posterior uterus POP patient were all greater than those of the anterior uterus POP patient.

CONCLUSIONS

The finite element model of USL and CL is completely based on the MRI technology and the model is real and reliable. The increase of abdominal pressure will produce a larger stress and deformation of USL and CL, which is one of the reasons causing the injury of the ligament.

The dysregulation of endoplasmic reticulum stress response in acute-on-chronic liver failure patients caused by acute exacerbation of chronic hepatitis B

Although endoplasmic reticulum (ER) stress is critical in various liver diseases, its role in acute-on-chronic liver failure (AoCLF) caused by acute exacerbation of chronic hepatitis B (CHB) is still elusive. This study aimed to analyse ER stress responses in the progression of HBV-related AoCLF. Normal liver tissues (n = 10), liver tissues of CHB (n = 12) and HBV-related patients with AoCLF (n = 19) were used. Electron microscopy of the ultrastructure of the ER was carried out on liver specimens. The gene and protein expression levels of ER stress-related genes were measured. We further analysed the correlation between the expression levels of ER stress-related molecules and liver injury. Electron microscopy identified typical features of the ER microstructure in AoCLF subjects. Among the three pathways of unfolded protein responses, the PKR-like ER kinase and inositol-requiring enzyme 1 signalling pathway were activated in CHB subjects and inactivated in AoCLF subjects, while the activating transcription factor 6 signalling pathway was sustained in the activated form during the progression of AoCLF; the expression of glucose-regulated protein (Grp)78 and Grp94 was gradually decreased in AoCLF subjects compared to healthy individuals and CHB subjects, showing a negative correlation with serum ALT, AST and TBIL; moreover, the ER stress-related apoptosis molecules were activated in the progression of acute exacerbation of CHB. The dysregulated ER stress response may play a complicated role in the pathogenesis of AoCLF, and a severe ER stress response may predict the occurrence of AoCLF caused by acute exacerbation of CHB.

Mutation screening of DUOX2 in Chinese patients with congenital hypothyroidism

BACKGROUND

Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder in infancy. Dual oxidase 2 gene (DUOX2) mutations have been reported to be one of the leading genetic causes of CH.

AIM

The aim of this study was to screen for DUOX2 gene mutations among CH patients in the Guangxi Zhuang Autonomous Region of China and to define the relationships between DUOX2 genotypes and clinical phenotypes.

MATERIALS AND METHODS

Blood samples were collected from 45 CH patients in Guangxi Zhuang Autonomous Region, China, and genomic DNA was extracted from peripheral blood leukocytes. All exons of the DUOX2 gene together with their exon-intron boundaries were screened by Sanger sequencing.

RESULTS

Sequencing analysis of DUOX2 in 45 CH patients revealed ten different variants in thirteen individuals. The variants included five known mutations, namely c.3329G>A (p.R1110Q), c.1588A>T (p.K530X), c.2635G>A (p.E879K), c.2524C>T (p.R842X) and c.4027G>T (p.L1343F), and one novel frame shift variant c.3340delC (p.L1114SfsX56), as well as four novel missense variants c.903G>T (p.W301C), c.2048G>T (p.R683L), c.1736T>C (p.L579P) and c.3413C>A (p.A1138D). The variant p.K530X is highly recurrent in our patient cohort but the clinical phenotypes vary greatly among those carrying this variant. Most patients with monoallelic or biallelic DUOX2 pathogenic variants turned out to be cases of transient congenital hypothyroidism (TCH), while three patients with triallelic DUOX2 pathogenic variants were associated with permanent congenital hypothyroidism (PCH).

CONCLUSIONS

The prevalence of DUOX2 pathogenic variants was high (29 %) among patients with CH in Guangxi, China. Monoallelic and biallelic DUOX2 pathogenic variants were mainly associated with TCH, while triallelic DUOX2 pathogenic variants were associated with PCH. Our study expanded the DUOX2 mutation spectrum, and functional studies of the novel mutations need to be conducted in the future.

Gankyrin facilitates follicle-stimulating hormone-driven ovarian cancer cell proliferation through the PI3K/AKT/HIF-1α/cyclin D1 pathway

Gankyrin is a regulatory subunit of the 26kD proteasome complex. As a novel oncoprotein, gankyrin is expressed aberrantly in cancers from several different sites and has been shown to contribute to oncogenesis in endometrial and cervical carcinomas. Neither gankyrin's contribution to the development of epithelial ovarian cancer nor its interaction with follicle-stimulating hormone (FSH)-driven proliferation in ovarian cancer has been studied. Here we have found that gankyrin is overexpressed in ovarian cancers compared with benign ovarian cystadenomas and that gankyrin regulates FSH upregulation of cyclin D1. Importantly, gankyrin regulates PI3K/AKT signaling by downregulating PTEN. Prolonged AKT activation by FSH stimulation of the FSH receptor (FSHR) promotes gankyrin expression, which, in turn, enhances AKT activation by inhibiting PTEN. Overexpression of gankyrin decreases hypoxia inducible factor-1α (HIF-1α) protein levels, but has little effect on HIF-1α mRNA levels, which could be attributed to gankyrin mediating HIF-1α protein stability via the ubiquitin-proteasome pathway. Reduction in HIF-1α protein stability led to attenuation of the binding with cyclin D1 promoter, resulted in abolishment of the negative regulation of cyclin D1 by HIF-1α, which promotes proliferation of ovarian cancer cells. Our results document that gankyrin regulates HIF-1α protein stability and cyclin D1 expression, ultimately mediating FSH-driven ovarian cancer cell proliferation.

The endoplasmic reticulum stress response is associated with insulin resistance-mediated drug resistance in HepG2 cells

Insulin resistance has a close relationship with tumorigenesis, tumor progression, and cancer prognosis. Importantly, the liver is the main target tissue of insulin, and the resistance to chemotherapeutic agents has been reported in hepatocarcinoma. However, little is known about the relationship between drug resistance and insulin resistance in hepatocarcinoma. Therefore, we treated HepG2 cells (a human hepatoma cell line) with high concentrations of insulin to establish a cell-based model of insulin resistance (HepG2/IR cells) to define the relationship between insulin resistance and the resistance to chemotherapy. We identified that HepG2/IR cells exhibited stable insulin resistance, with decreased glucose consumption, reduced glycogen synthesis, and decreased expression of the insulin receptor gene. HepG2/IR cells also exhibited endoplasmic reticulum (ER) dilatation and degranulation. Molecular markers of endoplasmic reticulum stress, including glucose-regulated protein78 (GRP78) and phosphorylated protein kinase R-like ER kinase (p-PERK), increased significantly, which was accompanied by increased reactive oxygen metabolism and decreased mitochondrial membrane potential. In addition, HepG2/IR cells were resistant to the chemotherapy agent Adriamycin, which was accompanied by the upregulation of multidrug resistance gene 1/ P-glycoprotein (P-gp; an endoplasmic reticulum chaperone that plays a role in ER stress), and enhanced drug efflux. These data suggest that the endoplasmic reticulum (ER) stress response was active in HepG2/IR cells, and that insulin resistance was related to drug resistance in HepG2 cells. Interestingly, the ER stress and chemotherapy resistance observed in HepG2/IR cells could be reversed by treatment with the insulin sensitizer pioglitazone. Therefore, our study suggests that there is a close relationship between the resistance to chemotherapy and insulin resistance in HepG2 cells, and that the ER stress response play a role in insulin resistance-mediated drug resistance in hepatocarcinoma cells.

KEYWORDS

Insulin resistance, drug resistance, P-gp, endoplasmic reticulum stress, HepG2 cells.

Isolation and characterization of 16 polymorphic microsatellite loci for Euchiloglanis kishinouyei

A total of 16 novel polymorphic microsatellite marker loci were isolated from a genomic library of Euchiloglanis kishinouyei and further characterized using a sample from a wild population consisting of 40 individuals. The number of alleles among loci ranged from three to 17 and the observed and expected heterozygosities ranged from 0·030 to 0·950 and 0·163 to 0·980, respectively. The average polymorphic information content (PIC) of all loci was 0·450.

The expression of P2X7 receptors on peripheral blood mononuclear cells in patients with primary Sjögren's syndrome and its correlation with anxiety and depression

OBJECTIVES

To study surface expression of P2X7 receptors (P2X7R) on peripheral blood mononuclear cells (PBMC) in patients with primary Sjögren's syndrome (pSS), and its correlation with anxiety and/or depression.

METHODS

The Hamilton Anxiety Scale (HAMA) and Hamilton Rating Scale for Depression (HRSD) were used to assess 31 patients with pSS. P2X7R expression on the surface of CD14+ and CD14- PBMC, with or without ATP stimulation, was measured by flow cytometry. IL-1β and IL-6 levels in blood plasma and supernatant after ATP stimulation were measured by ELISA. Nineteen patients with rheumatoid arthritis (RA), 18 patients with anxiety and/or depression, and 20 healthy cases were used as controls.

RESULTS

P2X7R expression was detected in all subjects. Compared with no ATP stimulation, significant up-regulation of P2X7R expression on CD14+ PBMC was observed after ATP stimulation in the pSS group only (p=0.001), while on CD14- PBMC there was significant up-regulation in both the pSS (p<0.001) and anxiety/depression (p=0.003) groups. After ATP stimulation, P2X7R expression on CD14+ PBMC in the pSS group was significantly higher than the RA group (p=0.044), anxiety/depression group (p=0.004) and healthy controls (p=0.002). Moreover, in the pSS group, P2X7R expression on CD14+ PBMC was significantly positively correlated to IL-1β supernatant levels (r=0.447, p=0.025). Overall, there were 45.2% (14/31) patients with anxiety and 32.3% (10/31) with depression, in the pSS group. P2X7R expression on CD14- PBMC was significantly positively correlated to scores of anxiety (r=0.344, p=0.030) and depression (r=0.319, p=0.045).

CONCLUSIONS

Surface expression of P2X7R on PBMC in patients with pSS was significantly higher than controls, suggesting P2X7R may contribute to the complex pathogenesis of pSS and also anxiety and/or depression.

Cooling Process Window Development for Injection Molding

The great impact of the injection molding cooling process on both productivity and product quality makes it essential to optimize the cooling conditions as well as the cooling system design. The current practice in injection molding process development, to identify the final operating conditions, which is a time consuming iteration between model design and product line, is costly in both material and time. This defect in the process development also raises the necessity to establish a method, which can provide the manufacturer not only with an optimum but also with a window around the optimum for the operating conditions, so as to avoid this time with consuming process to determine the feasible operating conditions. This paper presents a methodology, which combines an optimization algorithm with a mold cooling analysis, to obtain an optimal cooling processing condition and a cooling window in the injection molding of plastics as an aid for mold designing and manufacturing. The cooling effect, which is characterized through uniform cooling and short cooling time, is quantified in terms of mold cooling simulation output. A mathematical model is then formulated based on semi-empirical criteria and solved numerically by implementing an optimization algorithm. Based upon the resultant final optimum cooling condition, a relaxation scheme scheme is developed by the authors and performed, followed by a sensitivity analysis to determine the cooling window. At last, the application of this method is demonstrated by two industrial molds: a drilling housing and a compact drill battery pack. This approach will help in designing a proper cooling system for a mold and in determining an operating range to achieve better part quality and higher productivity.

Fast determination of antibiotics in whole blood

There is a need for analytical methods capable of monitoring blood antibiotic levels in real time. Here we present a method for quantifying antibiotic levels in whole blood that does not require any sample pretreatment. The tests employ the enzyme penicillinase to assay for penicillin G, penicillin V and ampicillin using a flow-injected biosensor, the Enzyme Thermistor. Optimal flow rates, sample volumes and pH were determined to be 0.5 mL/min, 100 μL and 7.0, respectively. Analysis of the antibiotics diluted in buffer gave a linear range of 0.17-5.0 mM. Calibration curves prepared using blood spiked with the antibiotics gave a linear range of 0.17-2.0 mM. Linear regression values for all of the calibration curves were 0.998 or higher. Assay cycle time was 5 min. The relative standard deviation value for 100 determinations of a mock blood sample spiked with penicillin G was 6.71%. Despite the elimination of sample pretreatment, no detectable clogging or signal drift was observed. The assay provides a fast, simple, reliable analytical method for determining antibiotic concentrations in blood without the need for any sample pretreatment. This is an important first step towards developing a device capable of real-time monitoring of antibiotic levels in whole blood. The technology has the potential to significantly improve the outcomes of patients undergoing critical care.

Evaluating the efficacy of current clinical practice of adjuvant chemotherapy in postmenopausal women with early-stage, estrogen or progesterone receptor-positive, one-to-three positive axillary lymph node, breast cancer

PURPOSE

We evaluated the benefit of the current clinical practice of adjuvant chemotherapy for postmenopausal women with early-stage, estrogen- or progesterone-receptor-positive (er/pr+), one-to-three positive axillary lymph node (1-3 ln+), breast cancer (esbc).

METHODS

Using the Manitoba Cancer Registry, we identified all postmenopausal women diagnosed with er/pr+ 1-3 ln+ esbc during the periods 1995-1997, 2000-2002, and 2003-2005 (n = 156, 161, and 171 respectively). Treatment data were obtained from the Manitoba Cancer Registry and by linkage with Manitoba administrative databases. Seven-year survival data were available for the 1995-1997 and 2000-2002 populations. Using Cox regression, we assessed the independent effect of the clinical practice of adjuvant chemotherapy on disease-free (dfs) and overall survival (os).

RESULTS

Clinical breast cancer treatments did not differ significantly between the 2000-2002 and 2003-2005 populations. Adjuvant chemotherapy was administered in 103 patients in the 2000-2002 population (64%) and in 44 patients in the 1995-1997 population [28.2%; mean difference: 36%; 95% confidence interval (ci): 31% to 40%; p < 0.0001]. Compared with 1995-1997, 2000-2002 was not significantly associated with an incremental dfs benefit for patients over a period of 7 years (2000-2002 vs. 1995-1997; adjusted hazard ratio: 0.98; 95% ci: 0.64 to 1.4).

CONCLUSIONS

The treatment standard of adjuvant chemotherapy in addition to endocrine therapy may not be effective for all women with er/pr+ 1-3 ln+ esbc. There could be a subgroup of those women who do not benefit from adjuvant chemotherapy as expected and who are therefore being overtreated. Further studies with a larger sample size are warranted to confirm our results.

Protective effect of Puerarin on β-amyloid-induced neurotoxicity in rat hippocampal neurons

Puerarin (CAS Number 3681-99-0), a major isoflavone glycoside purified from Pueraria lobata, was reported to possess antioxidative and estrogen-like biological activities. Recent studies showed that puerarin protects different cell types from damage caused by a variety of toxic stimuli. In the present study, we investigated the neuroprotective effect of puerarin against Aβ25-35-induced neurotoxicity in cultured hippocampal neurons, as well as the underlying mechanism(s). Following exposure of cells to Aβ25-35, cell survival and glutathione peroxidase (GSH-Px) and catalase (CAT) activities were reduced while production of reactive oxygen species (ROS) was increased. Preincubation of the cells with puerarin prior to Aβ25-35 exposure increased cell survival and GSH-Px and CAT activities and decreased ROS production. It was previously shown that overactivation of glycogen synthase kinase-3β (GSK-3β) is implicated in Aβ-induced cell death. In this study, Aβ25-35 treatment is found to increase GSK-3β activity and pretreatment with puerarin preventesAβ-induced activation of GSK-3β based on Western blot analysis. In addition, puerarin is shown to activate protein kinase B (PKB)/Akt, an important upstream kinase of GSK-3β, possibly promoting subsequent GSK-3β inhibition. Our data suggest that puerarin attenuates cell death induced by Aβ25-35 via various mechanisms, which might be beneficial for the treatment of Alzheimer's disease.

Dysfunction of fronto-limbic brain circuitry in depression

BACKGROUND

depression is characterized by a stable negative bias toward emotional stimuli. This bias is associated with abnormal activities in emotion-processing regions (such as the amygdala) and cognitive-control regions (such as the dorsolateral prefrontal cortex [DLPFC]). However, it remains unclear whether the emotion-processing and cognitive-control regions affect negative cognitive bias independently or reciprocally.

EXPERIMENTAL PROCEDURE

a functional magnetic resonance imaging (fMRI) study of 16 depressed patients and 16 matched control subjects was conducted during an emotion-interference task.

RESULTS

the accuracies were significantly lower in the depressed group than in the control group when subjects attended to the happy and the neutral faces. Compared with control participants, depressed patients showed abnormal activity in bilateral amygdala and the right DLPFC. In addition, a significant correlation was found between the right amygdala and the right DLPFC when subjects observed the happy faces.

CONCLUSIONS

the results suggest that the dysfunction in positive emotion-processing and cognitive-control regions may reciprocally affect negative cognitive bias. Additionally, altered positive emotional interference processing in the fronto-limbic brain circuitry might be another cause of negative cognitive bias that finally leads to depression.

Increase in Body Mass Index, Waist Circumference and Waist-to-Height Ratio is Associated with High Blood Pressure in Children and Adolescents in China

This study compared the association between blood pressure (BP) and obesity in 1145 Chinese children and adolescents (608 males, 537 females) using data from the 2006 China Health and Nutrition Survey. Obesity was diagnosed by body mass index (BMI), waist circumference (WC) and waist-to-height ratio (WHtR). Analysis of variance was used to analyse the difference in BP among different subgroups. Odds ratios (OR) were calculated and multivariate logistic regression analysis was carried out. The prevalence of high systolic and diastolic BP increased directly with corresponding increments in BMI, WC and WHtR, although the prevalence and OR of high BP were higher when increased BMI was combined with WC (OR 3.39; 95% confidence interval [CI] 1.79, 6.41) or WHtR (OR 3.28; 95% CI 1.71, 6.30). In conclusion, increased BMI, WC and WHtR were directly associated with high BP in Chinese children and adolescents.