Numb induces e-cadherin adhesion dissolution, cytoskeleton reorganization, and migration in tubular epithelial cells contributing to renal fibrosis

Numb, an endocytic protein, is involved in both neural differentiation and protein post-endocytic trafficking. Although negative Numb expression has been linked to human mammary carcinomas, little is known about its expression and functions in other diseases. In the present study, we observed that Numb is expressed in renal tubule epithelia and its expression is increased in the fibrotic kidney in vivo. We determined that in proximal tubular epithelial cells (NRK52E cells), TGF-β1 induces the expression of Numb and ectopic expression of Numb leads to dissolution of E-cadherin adhesion, reorganization of cytoskeleton, activation of Rac1 and Cdc42, and enhancement of migration. Either knockdown of α-adaptin or overexpression of Numb asparagine-proline-phenylalanine (NPF) mutant interferes with AP-2 dependent endocytosis and rescues Ecadherin level in NRK52E cells. Moreover, knockdown of integrin β1 or α-adaptin, and overexpression of a Numb dominant-negative form (Numb phosphotyrosine binding [PTB] domain) impair integrin endocytosis, and markedly inhibit Numb-induced cell migration and activation of Rac1 and Cdc42. Taken together, our work identifies Numb as an important player in renal fibrosis, by regulating epithelial-to-mesenchymal transition (EMT) process including E-cadherin adhesion dissolution, actin reorganization, and migration enhancement in NRK52E cells.

Identification and comparative proteomic study of quail and duck egg white protein using 2-dimensional gel electrophoresis and matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry analysis

A proteomic study of egg white proteins from 2 major poultry species, namely quail (Coturnix coturnix) and duck (Anas platyrhynchos), was performed with comparison to those of chicken (Gallus gallus) through 2-dimensional polyacrylamide gel electrophoresis (2-DE) analysis. By using matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF MS/MS), 29 protein spots representing 10 different kinds of proteins as well as 17 protein spots designating 9 proteins were successfully identified in quail and duck egg white, respectively. This report suggested a closer relationship between quail and chicken egg white proteome patterns, whereas the duck egg white protein distribution on the 2-DE map was more distinct. In duck egg white, some well-known major proteins, such as ovomucoid, clusterin, extracellular fatty acid-binding protein precursor (ex-FABP), and prostaglandin D2 synthase (PG D2 synthase), were not detected, while two major protein spots identified as “deleted in malignant brain tumors 1” protein (DMBT1) and vitellogenin-2 were found specific to duck in the corresponding range on the 2-DE gel map. These interspecies diversities may be associated with the egg white protein functions in cell defense or regulating/supporting the embryonic development to adapt to the inhabiting environment or reproduction demand during long-term evolution. The findings of this work will give insight into the advantages involved in the application on egg white proteins from various egg sources, which may present novel beneficial properties in the food industry or related to human health.

Risk of malignant progression in Barrett's esophagus indefinite for dysplasia

Barrett's esophagus is a well-recognized risk factor for esophageal adenocarcinoma. The natural history of Barrett's esophagus classified as ‘indefinite for dysplasia’ (IND) is poorly characterized. The aim of this study is to characterize the natural history of IND by determining the rate of neoplastic progression and identifying risk factors for progression. Patients from the University of Pennsylvania Health System pathology database and Barrett's esophagus registry with a diagnosis of IND between 2000 and 2014 were identified. Exclusion criteria included: (1) prior diagnosis of low-grade dysplasia (LGD), high-grade dysplasia (HGD), or esophageal adenocarcinoma (EAC); (2) presence of LGD, HGD, or EAC at the time of diagnosis of IND; and (3) lack of follow-up endoscopy after diagnosis. Patients with neoplastic progression were classified as having either prevalent disease (LGD, HGD, or EAC on surveillance biopsy within 12 months of IND diagnosis) or incident disease (LGD, HGD, or EAC on surveillance biopsy >12 months after IND diagnosis). One hundred six patients were eligible for analysis. Of 87 patients with follow-up endoscopy and biopsies within 1 year of IND diagnosis, 7 (8%) had prevalent disease (2 LGD, 4 HGD, 1 EAC). The prevalence of LGD was 2.3%, HGD was 4.6%, and EAC was 1.1%. Importantly, four of the seven prevalent (2 LGD, 2 HGD) cases were found to have dysplasia within 6 months of IND diagnosis. No demographic or endoscopic characteristics studied were associated with prevalent disease. Of the 106 IND patients, there were 66 patients without prevalent dysplasia with >1-year follow-up. Three (4.5%) progressed (1 to LGD after 12 months, 2 to HGD after 16.5 and 28 months), yielding an incidence rate for any dysplasia of 1.4 cases/100 person-years and HGD/EAC of 0.9/100 person-years. Risk factors for incident disease were smoking (p = 0.02) and Barrett's esophagus segment length (p = 0.03). IND is associated with considerable risk of prevalent dysplasia, especially within the first 6 months after diagnosis. However, the incidence of HGD/EAC is low and similar to previous studies of IND. These data suggest that IND patients should have repeat endoscopy within 6 months with careful surveillance protocols. Longer BE length and smoking history may help predict which patients are more likely to develop dysplasia, and therefore identify patients who may warrant even closer monitoring.

Function Clustering Self-Organization Maps (FCSOMs) for mining differentially expressed genes in Drosophila and its correlation with the growth medium

The central task of this study was to mine the gene-to-medium relationship. Adequate knowledge of this relationship could potentially improve the accuracy of differentially expressed gene mining. One of the approaches to differentially expressed gene mining uses conventional clustering algorithms to identify the gene-to-medium relationship. Compared to conventional clustering algorithms, self-organization maps (SOMs) identify the nonlinear aspects of the gene-to-medium relationships by mapping the input space into another higher dimensional feature space. However, SOMs are not suitable for huge datasets consisting of millions of samples. Therefore, a new computational model, the Function Clustering Self-Organization Maps (FCSOMs), was developed. FCSOMs take advantage of the theory of granular computing as well as advanced statistical learning methodologies, and are built specifically for each information granule (a function cluster of genes), which are intelligently partitioned by the clustering algorithm provided by the DAVID_6.7 software platform. However, only the gene functions, and not their expression values, are considered in the fuzzy clustering algorithm of DAVID. Compared to the clustering algorithm of DAVID, these experimental results show a marked improvement in the accuracy of classification with the application of FCSOMs. FCSOMs can handle huge datasets and their complex classification problems, as each FCSOM (modeled for each function cluster) can be easily parallelized.

Yes-associated protein (YAP) expression is involved in epithelial-mesenchymal transition in hepatocellular carcinoma

PURPOSE

To investigate biological impact of the downregulation of yes-associated protein (YAP) through RNA interference in the process of epithelial-mesenchymal transition in MHCC97H and MHCC97L.

METHODS

MHCC97H and MHCC97L cells were transiently transfected by YAP-siRNA. Furthermore, protein expressions and mRNA levels of characteristic markers of epithelial-mesenchymal transition (E-cadherin, N-cadherin) were examined by Western blotting and real-time polymerase chain reaction, and transwell invasion assay was used to detect changes of invasiveness of MHCC97H and MHCC97L cells.

RESULTS

The transfected group with YAP-siRNA in MHCC97H after 72 h by Western blotting showed obviously higher expression of E-cadherin compared with the control group (P < 0.05), and lower expression of N-cadherin (P < 0.05). In MHCC97L cells, the expression of E-cadherin was also significantly increased (P < 0.05); however, N-cadherin expression did not significantly change (P > 0.05). Moreover, compared with the control group, Transwell invasion assay showed that the number of the transfected groups was significantly decreased in MHCC97H and MHCC97L cell lines (both P < 0.05). The result of real-time polymerase chain reaction indicated that mRNA levels of E-cadherin increased (P < 0.05), but the mRNA levels of N-cadherin did not significantly change (P > 0.05) in these two cell lines, indicating some effects of post-transcriptional regulation mechanism after silencing YAP.

CONCLUSIONS

YAP expression in human hepatocellular carcinoma cell lines MHCC97H and MHCC97L is closely related with the characteristic markers of epithelial-mesenchymal transition, N-cadherin and E-cadherin expression.

Online monitoring of oil film using electrical capacitance tomography and level set method

In the application of oil-air lubrication system, electrical capacitance tomography (ECT) provides a promising way for monitoring oil film in the pipelines by reconstructing cross sectional oil distributions in real time. While in the case of small diameter pipe and thin oil film, the thickness of the oil film is hard to be observed visually since the interface of oil and air is not obvious in the reconstructed images. And the existence of artifacts in the reconstructions has seriously influenced the effectiveness of image segmentation techniques such as level set method. Besides, level set method is also unavailable for online monitoring due to its low computation speed. To address these problems, a modified level set method is developed: a distance regularized level set evolution formulation is extended to image two-phase flow online using an ECT system, a narrowband image filter is defined to eliminate the influence of artifacts, and considering the continuity of the oil distribution variation, the detected oil-air interface of a former image can be used as the initial contour for the detection of the subsequent frame; thus, the propagation from the initial contour to the boundary can be greatly accelerated, making it possible for real time tracking. To testify the feasibility of the proposed method, an oil-air lubrication facility with 4 mm inner diameter pipe is measured in normal operation using an 8-electrode ECT system. Both simulation and experiment results indicate that the modified level set method is capable of visualizing the oil-air interface accurately online.

Treatment and mechanism of BMMSCs on deep II degree scald of hamster skin

In this study, we examined the treatment and mechanism of BMMSC on a deep II degree scald of the hamster skin. A deep II degree scald model on the skin of 40 hamsters was duplicated and divided randomly into a stem cell plantation group (group A) and model control group (group B). Skin cells were cultured in vitro until the allogeneic BMMSCs of the 5th generation formed with a cell count of 1 x 10(7)/mL. Local injection plus liquid supernatant smearing was used to plant the cells into the position of the scald in the stem cell plantation group. The control group was given an equivalent amount of normal saline to observe the healing action, and 5 samples were taken in each group after 1, 3, 7, and 14 days for hematoxylin and eosin staining for physiological observation. Polymerase chain reaction was used to detect the amount of chymotrypsin in mast cells. The speed of healing in the stem cell transplantation group was greater than that in the control group; staining results showed that the quality of healing in the transplantation group was better than that in the control group. Chymotrypsin expression was detected in both groups, reaching a peak on day 3. BMMSCs can accelerate wound healing, and chymotrypsin in mast cells may participate in the wound healing process.

Prone positioning decreases cardiac output and increases systemic vascular resistance in neonates

OBJECTIVE

To evaluate the cardiovascular response to short-term prone positioning in neonates.

STUDY DESIGN

In this prospective study, we continuously monitored heart rate (HR), stroke volume (SV) and cardiac output (CO) by electrical velocimetry in hemodynamically stable neonates in each of the following positions for 10 min: supine, prone and back-to-supine position. Skin blood flow (SBF) was also continuously assessed on the forehead or foot using Laser Doppler technology. Systemic vascular resistance (SVR) index was calculated as mean blood pressure (BP)/CO. Data were analyzed using repeated measures analysis of variance.

RESULTS

Thirty neonates (gestational age: 35±4 weeks; postmenstrual age: 36±3 weeks) were enrolled. HR did not change in response to positioning. However, in prone position, SV, CO and SBF decreased and SVR index increased from 1.5±0.3 to 1.3±0.3 ml kg(-1) (mean ±s.d., P<0.01), 206±44 to 180±41 ml kg(-1) min(-1) (P<0.01), 0.54±0.30 to 0.44±0.29 perfusion units (P<0.01) and 0.25±0.06 to 0.30±0.07 mm Hg ml(-1) kg(-1) min(-1) (P<0.01), respectively. After placing the infants back-to-supine position, SV, CO, SBF and SVR index returned to baseline. The above pattern of cardiovascular changes was consistent in vast majority of the studied neonates.

CONCLUSIONS

Short-term prone positioning is associated with decreased SV, CO and SBF and increased calculated SVR index.

The timecourse of apoptotic cell death during postnatal remodeling of the mouse cochlea and its premature onset by triiodothyronine (T3)

Apoptosis underlies various forms of tissue remodeling during development. Prior to the onset of hearing, thyroid hormone (T3) promotes cochlear remodeling, which involves regression of the greater epithelial ridge (GER), a transient structure of columnar cells adjacent to the mechanosensory hair cells. We investigated the timecourse of apoptosis in the GER and the influence of ectopic T3 on apoptosis. In saline-treated mice, activated caspase 3-positive cells were detected in the GER between postnatal days 7 and 13 and appeared progressively along the cochlear duct from base to apex over developmental time. T3 given on P0 and P1 advanced the overall program of apoptosis and remodeling by ~4 days. Thyroid hormone receptor β was required for these actions, suggesting a receptor-mediated process of initiation of apoptosis. Finally, T3 given only at P0 or P1 resulted in deafness in adult mice, thus revealing a transient period of susceptibility to long-term damage in the neonatal auditory system.

Protease inhibitor-based triple therapy is highly effective for hepatitis C recurrence after liver transplant: a multicenter experience

INTRODUCTION

Hepatitis C (HCV) continues to be the leading indication for liver transplantation (LT). Sustained virological response (SVR) rates to pegylated interferon (PEG-IFN) and ribavirin (RBV) therapy for recurrent HCV in Genotype 1 (G1) LT recipients have been disappointing (30-40%). Experience with triple therapy using protease inhibitors (PI) boceprevir (BOC), telaprevir (TVR) in these patients has been limited.

MATERIAL AND METHODS

This national multicenter retrospective study included 76 patients (64 male, mean age 57 ± 6 years), treated for G1 HCV recurrence with either BOC (n = 41) or TVR (n = 35), who were non-responders or relapsers (n = 54), treatment naïve (n = 22) or had fibrosing cholestatic HCV (n = 3). 53 patients were on cyclosporine, 22 on tacrolimus and one patient on prednisone alone.

RESULTS

On treatment virologic response was observed in 84% (64/76), 83% in BOC and 85% in TVR group. A higher week 4 response after starting triple therapy (RVR) was noted in TVR group 25/35 (81%) as compared to BOC group 26/41 (63%); p value = 0.02. The end of treatment response was 78% and 75% in BOC and TVR group, respectively. SVR 12 weeks after treatment discontinuation was observed in 59.5% (22/37); 58.3% in the BOC group and 61.5% in TVR group. Treatment was discontinued early in 23 patients (serious adverse effects n = 19, treatment failure n = 4). Infections occurred in 5 patients with 2 deaths (all in BOC). Anemia was the most common side effect (n = 55, 72%) requiring erythropoietin and RBV dose reduction. In the BOC group, cyclosporine dose reduction was 2.2 ± 1.0 fold and 8.6 ± 2.4 fold with tacrolimus. In TVR group, dose reduction was 3.0 ± 1.4 with cyclosporine and 12 ± 5.7 fold with tacrolimus.

CONCLUSIONS

PI-based triple therapy appears more effective in producing HCV-RNA clearance than dual therapy. Tolerability is a serious issue and drug-drug interactions are manageable with close monitoring.

Household transmissibility of avian influenza A (H7N9) virus, China, February to May 2013 and October 2013 to March 2014

To study human-to-human transmissibility of the avian influenza A (H7N9) virus in China, household contact information was collected for 125 index cases during the spring wave (February to May 2013), and for 187 index cases during the winter wave (October 2013 to March 2014). Using a statistical model, we found evidence for human-to-human transmission, but such transmission is not sustainable. Under plausible assumptions about the natural history of disease and the relative transmission frequencies in settings other than household, we estimate the household secondary attack rate (SAR) among humans to be 1.4% (95% CI: 0.8 to 2.3), and the basic reproductive number R0 to be 0.08 (95% CI: 0.05 to 0.13). The estimates range from 1.3% to 2.2% for SAR and from 0.07 to 0.12 for R0 with reasonable changes in the assumptions. There was no significant change in the human-to-human transmissibility of the virus between the two waves, although a minor increase was observed in the winter wave. No sex or age difference in the risk of infection from a human source was found. Human-to-human transmissibility of H7N9 continues to be limited, but it needs to be closely monitored for potential increase via genetic reassortment or mutation.

Insufficient Protein Intake Is Associated With Increased Mortality in 630 Patients With Cirrhosis Awaiting Liver Transplantation

BACKGROUND

For patients awaiting liver transplantation, we aimed to determine the prevalence and predictors of insufficient protein intake as well as to determine whether very low protein intake was an independent predictor of malnutrition and mortality.

MATERIALS AND METHODS

Adults with cirrhosis who were activated on our local liver transplant waiting list between January 2000 and October 2009 were included. Estimated protein intake was derived from dietary records. Patients with incomplete dietary records were excluded. Multivariable logistic regression and competing risk analysis were used.

RESULTS

Of 742 potential patients, 112 were excluded due to insufficient data, leaving 630 patients for evaluation. Mean protein intake was 1.0 ± 0.36 g/kg/d and only 24% of patients met the expert consensus recommended threshold of > 1.2 g/kg of protein per day. Very low protein intake (< 0.8 g/kg/d) was associated with worse liver disease severity (as measured by Child-Pugh or MELD). Protein intake below 0.8 g/kg/d was an independent predictor both of malnutrition as measured by the subjective global assessment (adjusted odds ratio [95% confidence interval (CI)]: 2.0 [1.3-3.0]) and of transplant waiting list mortality (adjusted hazard ratio [95% CI]: 1.8 [1.2-2.7]).

CONCLUSION

In this large cohort of liver transplant waitlisted patients, very low protein intake was prevalent and independently associated with malnutrition and mortality. Unlike many other prognostic factors, protein intake is potentially modifiable. Prospective studies are warranted to evaluate the effect of targeted protein repletion on clinically relevant outcomes such as muscle mass, muscle function, immune function, and mortality.

Eight weeks of exercise training increases aerobic capacity and muscle mass and reduces fatigue in patients with cirrhosis

BACKGROUND & AIMS

Patients with cirrhosis have reduced exercise tolerance, measured objectively as decreased peak exercise oxygen uptake (peak VO2). Reduced peak VO2 is associated with decreased survival time. The effect of aerobic exercise training on peak VO2 has not been well studied in patients with cirrhosis. We evaluated the safety and efficacy of 8 weeks of supervised exercise on peak VO2, quadriceps muscle thickness, and quality of life.

METHODS

In a prospective pilot study, stable patients (79% male, 57.6 ± 6.7 years old) with Child-Pugh class A or B cirrhosis (mean Model for End-Stage Liver Disease score, 10 ± 2.2) were randomly assigned to groups that received exercise training (n = 9) or usual care (controls, n = 10) at the University of Alberta Hospital in Canada from February through June 2013. Supervised exercise was performed on a cycle ergometer 3 days/week for 8 weeks at 60%-80% of baseline peak VO2. Peak VO2, quadriceps muscle thickness (measured by ultrasound), thigh circumference, answers from Chronic Liver Disease Questionnaires, EQ-visual analogue scales, 6-minute walk distance, and Model for End-Stage Liver Disease scores were evaluated at baseline and at week 8. Analysis of covariance was used to compare variables.

RESULTS

At week 8, peak VO2 was 5.3 mL/kg/min higher in the exercise group compared with controls (95% confidence interval, 2.9-7.8; P = .001). Thigh circumference (P = .001), thigh muscle thickness (P = .01), and EQ-visual analogue scale determined self-perceived health status (P = .01) was also significantly higher in the exercise group compared with controls at week 8; fatigue subscores of the Chronic Liver Disease Questionnaires were lower in the exercise group compared with controls (P = .01). No adverse events occurred during cardiopulmonary exercise testing or training.

CONCLUSIONS

In a controlled prospective pilot trial, 8 weeks of supervised aerobic exercise training increased peak VO2 and muscle mass and reduced fatigue in patients with cirrhosis. No relevant adverse effects were observed. Larger trials are needed to evaluate the effects of exercise in patients with cirrhosis. ClinicalTrials.gov number: NCT01799785.

Asymptomatic bacteriuria is an independent predictor of urinary tract infections in an ambulatory cirrhotic population: a prospective evaluation

BACKGROUND & AIMS

Asymptomatic bacteriuria (ASB) is a risk factor for urinary tract infections (UTIs) in many patients without liver disease. It remains unclear whether a diagnosis of ASB in an outpatient with cirrhosis could be utilized to predict the subsequent development of a UTI. We undertook this study to determine the prevalence and incidence of ASB in an outpatient population and its association with UTI.

METHODS

We prospectively evaluated 108 adult outpatients with cirrhosis over a 6-month period. Monthly midstream urines (MSU) were performed to detect the occurrence of UTI and ASB (culture of ≥10(8) CFU/L of a urinary pathogen in the absence of UTI symptoms).

RESULTS

Of 108 patients enrolled, 99 completed at least one MSU, for a total of 489 MSUs. Total follow-up was 44 person-years. The incidences of ASB and UTI were 181 and 250 per 1000 person-years, respectively. The prevalences of ASB and UTI on the first MSU were 5 and 1%, respectively. In total, 8% of patients developed an episode of ASB and 11% developed a UTI during the study period. Univariate predictors of UTI were female gender, primary biliary cirrhosis, number of previous UTIs and preceding ASB. Preceding ASB was the only independent predictor of UTI on multivariate analysis, with an odds ratio of 6.2 (1.1-34.3), P = 0.04.

CONCLUSIONS

Cirrhotic patients have higher rates of ASB and UTI than reported in the general population. ASB is an independent predictor of UTI. Further studies are necessary to determine whether routine screening and antimicrobial treatment of ASB is warranted.

LincRNA-ROR induces epithelial-to-mesenchymal transition and contributes to breast cancer tumorigenesis and metastasis

LncRNAs have critical roles in various biological processes ranging from embryonic development to human diseases, including cancer progression, although their detailed mechanistic functions remain illusive. The lncRNA linc-ROR has been shown to contribute to the maintenance of induced pluripotent stem cells and embryonic stem cells. In this study, we discovered that linc-ROR was upregulated in breast tumor samples, and ectopic overexpression of linc-ROR in immortalized human mammary epithelial cells induced an epithelial-to-mesenchymal transition (EMT) program. Moreover, we showed that linc-ROR enhanced breast cancer cell migration and invasion, which was accompanied by generation of stem cell properties. Contrarily, silencing of linc-ROR repressed breast tumor growth and lung metastasis in vivo. Mechanistically, our data revealed that linc-ROR was associated with miRNPs and functioned as a competing endogenous RNA to mi-205. Specifically, linc-ROR prevented the degradation of mir-205 target genes, including the EMT inducer ZEB2. Thus our results indicate that linc-ROR functions as an important regulator of EMT and can promote breast cancer progression and metastasis through regulation of miRNAs. Potentially, the findings of this study implicate the relevance of linc-ROR as a possible therapeutic target for aggressive and metastatic breast cancers.

Severe muscle depletion predicts postoperative length of stay but is not associated with survival after liver transplantation

Muscle depletion or sarcopenia is associated with increased mortality in patients with cirrhosis; how it affects mortality after liver transplantation requires further study. In this study, we aimed to establish whether sarcopenia predicts increased morbidity or mortality after liver transplantation. We analyzed 248 patients with cirrhosis who had a computed tomography (CT) scan including the third lumbar vertebra before liver transplantation. Data were recovered from medical charts, the skeletal muscle cross-sectional area was measured with CT, and sarcopenia was defined with previously published sex- and body mass index-specific cutoffs. One hundred sixty-nine patients (68%) were male, and the mean age at transplantation was 55 ± 1 years. The etiologies of cirrhosis were hepatitis C virus (51%), alcohol (19%), autoimmune liver diseases (15%), hepatitis B virus (8%), and other etiologies (7%). Sarcopenia was present in 112 patients (45%), and it was more frequent in males (P = 0.002), patients with ascites (P = 0.02), and patients with higher bilirubin levels (P = 0.05), creatinine levels (P = 0.02), international normalized ratios (P = 0.04), Child-Pugh scores (P = 0.002), and Model for End-Stage Liver Disease scores (P = 0.002). The median survival period after liver transplantation was 117 ± 17 months for sarcopenic patients and 146 ± 20 months for nonsarcopenic patients (P = 0.4). Sarcopenic patients had longer hospital stays (40 ± 4 versus 25 ± 3 days; P = 0.005) and a higher frequency of bacterial infections within the first 90 days after liver transplantation (26% versus 15%, P = 0.04) in comparison with nonsarcopenic patients. In conclusion, sarcopenia is one of the most common complications in patients with cirrhosis and is predictive of longer hospital stays and a higher risk of perioperative bacterial infections after liver transplantation, but it is not associated with increased mortality.

Inhibition enhancer of zeste homologue 2 promotes senescence and apoptosis induced by doxorubicin in p53 mutant gastric cancer cells

OBJECTIVES

Enhancer of zeste homologue 2 (EZH2) is crucially involved in epigenetic silencing by acting as a histone methyltransferase. Although EZH2 is overexpressed in many cancers and is involved in malignant cell proliferation and invasion, the role of EZH2 in senescence induced by DNA damage has up to now remained largely unknown. In this study, we sought to explore the outcome of EZH2 depletion along with exposure of doxorubicin (DOX), and related mechanisms, in gastric cancer cells.

MATERIALS AND METHODS

Here, senescence induced by DNA damage was achieved in gastric cancer cells by DOX treatment. EZH2 was downregulated by transfection with siRNA or treated with (-)-epigallocatechin-3-gallate, a targeted inhibitor. Senescence-associated β galactosidase (SA-β-gal) and formation of senescence-associated heterochromatin foci were used to identify cell senescence. To investigate effects of EZH2 depletion on the cell cycle, apoptosis and proliferation, flow cytometry and MTT analysis were employed. Changes in p53-p21 axis activation were detected by Western blotting.

RESULTS

We found that cell proliferative arrest caused by DOX could be promoted by EZH2 depletion. Mechanistically, EZH2 depletion not only worked in coordination with DNA damage during the progression of cell senescence but also promoted apoptosis in p53 mutant cells. However, it had no cooperative relationship with DOX in p53 wild-type cells.

CONCLUSIONS

These data help unravel a crucial role for EZH2 in senescence and apoptosis in gastric cancer cells and that p53 genomic status was associated with different cell responses to EZH2 silencing.

A MELD-based model to determine risk of mortality among patients with acute variceal bleeding

BACKGROUND & AIMS

Patients with cirrhosis with acute variceal bleeding (AVB) have high mortality rates (15%-20%). Previously described models are seldom used to determine prognoses of these patients, partially because they have not been validated externally and because they include subjective variables, such as bleeding during endoscopy and Child-Pugh score, which are evaluated inconsistently. We aimed to improve determination of risk for patients with AVB.

METHODS

We analyzed data collected from 178 patients with cirrhosis (Child-Pugh scores of A, B, and C: 15%, 57%, and 28%, respectively) and esophageal AVB who received standard therapy from 2007 through 2010. We tested the performance (discrimination and calibration) of previously described models, including the model for end-stage liver disease (MELD), and developed a new MELD calibration to predict the mortality of patients within 6 weeks of presentation with AVB. MELD-based predictions were validated in cohorts of patients from Canada (n = 240) and Spain (n = 221).

RESULTS

Among study subjects, the 6-week mortality rate was 16%. MELD was the best model in terms of discrimination; it was recalibrated to predict the 6-week mortality rate with logistic regression (logit, -5.312 + 0.207 • MELD; bootstrapped R(2), 0.3295). MELD values of 19 or greater predicted 20% or greater mortality, whereas MELD scores less than 11 predicted less than 5% mortality. The model performed well for patients from Canada at all risk levels. In the Spanish validation set, in which all patients were treated with banding ligation, MELD predictions were accurate up to the 20% risk threshold.

CONCLUSIONS

We developed a MELD-based model that accurately predicts mortality among patients with AVB, based on objective variables available at admission. This model could be useful to evaluate the efficacy of new therapies and stratify patients in randomized trials.

VSL#3 ® probiotic therapy does not reduce portal pressures in patients with decompensated cirrhosis

BACKGROUND & AIMS

In patients with decompensated cirrhosis, bacterial translocation can contribute to splanchnic vasodilatation, decreased effective circulating volume, and portal hypertension. The primary objective of this randomized, double blind placebo controlled trial was to evaluate the effect of the probiotic VSL#3(®) on the hepatic venous pressure gradient (HVPG).

METHODS

Seventeen patients with decompensated cirrhosis and an HVPG of ≥ 10 mmHg were randomized to receive 2 months of VSL#3(®) or an identical placebo. HVPG, endotoxin, interleukin (IL)-6, IL-8, IL-10, renin, aldosterone, nitric oxide and stool microbiota were measured at baseline and study end.

RESULTS

Two of the 17 patients were taken off the trial before completion (one for alcohol abuse and the second for SBP - both in placebo arm). Data were analysed on the remaining 15 patients. The median model for end-stage liver disease score was 12, and 80% of patients had Child Pugh B disease. The treatment arm had a greater decrease in HVPG from baseline to study end than the placebo arm (median change from baseline -11.6% vs +2.8%), although this reduction was not statistically significant in either group. There was a significant reduction in the plasma aldosterone level in the VSL#3(®) group, but no significant changes in the other measured parameters, including the stool microflora analysis.

CONCLUSIONS

Within the limitations of our sample size, VSL#3(®) therapy does not appear to have a significant impact on portal pressure reduction in patients with decompensated cirrhosis.

The 22/11 risk prediction model: a validated model for predicting 30-day mortality in patients with cirrhosis and spontaneous bacterial peritonitis

OBJECTIVES

Clinicians do not have a validated tool for estimating the short-term mortality associated with spontaneous bacterial peritonitis (SBP). Accurate prognosis assessment is important for risk stratification and for individualizing therapy. We aimed therefore to develop and validate a model for the prediction of 30-day mortality in SBP patients receiving standard medical treatment (antibiotics and if indicated by guidelines, intravenous albumin therapy).

METHODS

We retrospectively identified SBP patients treated at a tertiary care center between 2003 and 2011 (training set). Multivariate regression modeling and receiver operating characteristic (ROC) curves were utilized for statistical analysis. An external data set of 109 SBP patients was utilized for validation.

RESULTS

Of the 184 patients in the training set, 66% were men with a median age of 55 years, a median MELD (Model for End-Stage Liver Disease) score of 20, and a 30-day mortality of 27%. Peripheral blood leukocyte count ≥11×10⁹ cells/l (odds ratio (OR) 2.5; 95% confidence interval CI: 1.2-5.2) and MELD score ≥22 (OR 4.6; 95% CI: 2.3-9.6) were independent predictors of 30-day mortality. Patients with neither, one, or both variables had 30-day mortality rates of 8%, 32%, and 52%, respectively. The findings in the validation set mirrored the training set.

CONCLUSIONS

In cirrhotic patients with SBP receiving standard therapy, MELD score ≥22 and peripheral blood leukocyte count ≥11×10⁹ cells/l are validated independent predictors of mortality. The mortality in a patient without either poor prognostic variable is ≤10% and with both variables is ≥50%. Trials aiming to reduce mortality should target patients in the moderate-risk to high-risk groups.

Mitochondrial bioenergetic deficits in the hippocampi of rats with chronic ischemia-induced vascular dementia

Vascular dementia (VD), defined as a loss of memory and cognitive function resulting from vascular lesions in the brain, is the second-most-common cause of dementia in the elderly, after Alzheimer's disease. In recent years, research has focused on the pathogenesis of VD, and mitochondrial bioenergetic deficits have been suggested to contribute to VD onset. To further investigate the role of mitochondria in VD, we used a rat model of VD, which involved permanent bilateral occlusion of the common carotid arteries (with a 1-week interval between artery occlusion to avoid an abrupt reduction in cerebral blood flow) leading to chronic cerebral hypoperfusion. Prior to occlusion, male Wistar rats underwent 7 days of Morris water maze training. Only animals that could swim and passed the Morris water maze test were chosen for the study. After 5 days of Morris water maze training, mitochondria from the hippocampi of rats, which were randomly selected from animals that could complete the Morris water maze test, were isolated for functional assessment. Mitochondria isolated from the hippocampi of rats from the ischemia group had decreased pyruvate dehydrogenase protein levels, and increased oxidative stress, as manifested by increased hydrogen peroxide production. The ischemia group mitochondria also exhibited decreased respiration coupled to decreased expression and activity of the electron transport chain complex IV (cytochrome c oxidase). These results indicate that the mitochondrial oxidative metabolism is inhibited in the hippocampi of rats following chronic ischemia-induced VD. As the mitochondrial oxidative metabolism deficits, namely mitochondrial bioenergetic deficits directly affect the functions of neurons, it may contribute to VD onset.

Apparent diffusion coefficients of normal uterus in premenopausal women with 3 T MRI

AIM

To investigate the apparent diffusion coefficient (ADC) values of the normal uterine cervical zonal structures (cervical epithelium, the junctional zone, and myometrium) during different phases of the menstrual cycle among premenopausal women in different age groups.

MATERIALS AND METHODS

Seventy healthy women, who were divided into three age groups (group A, 24 women in their twenties; group B, 23 women in their thirties; group C, 23 women in their forties), underwent 3 T magnetic resonance imaging (MRI) with T2-weighted and diffusion-weighted imaging (DWI) during the mid-proliferative and the mid-secretory phases.

RESULTS

The ADC values of each cervical zonal structure were significantly different from one another (p < 0.001). The ADC values of the epithelium and junctional zones were both lower during the mid-secretory phase than those during the mid-proliferative phase in each age group (p < 0.05). There were no significant differences in the ADC values of any of the cervical zones among the three age groups for a given phase (p > 0.05).

CONCLUSION

ADC values of normal cervical epithelium and the junctional zone change with different phases of the menstrual cycle, which should be taken into consideration when early cervical disease is detected, when monitoring treatment response, and differentiating early tumour recurrence.

Incidence and risk factors associated with de novo autoimmune hepatitis after liver transplantation

BACKGROUND/AIMS

De novo autoimmune hepatitis (AIH) describes the development of hepatitis with autoimmune features in liver transplant (LT) patients without prior diagnosis of AIH. We aimed to evaluate the incidence and risk factors for de novo AIH.

METHODS

A cohort of 576 patients with LT for aetiologies other than AIH was evaluated.

RESULTS

De novo AIH was diagnosed in 17 patients (3%) with an overall incidence of 4.0 cases per 1000 patient-years. By univariate Cox analysis, patients who received cyclosporine A had lower risk (HR 0.24, 95% CI 0.07-0.80, P = 0.02), whereas patients who had female donors (HR 3.03, 95% CI 1.11-8.25, P = 0.03), donors ≥40-years (HR 6.95, 95% CI 1.93-25.03, P = 0.003), and those who received tacrolimus (HR 4.39, 95% CI 1.47-13.13, P = 0.008) and mycophenolate mofetil (HR 6.37, 95% CI 1.62-25.13, P = 0.008) had higher risk. Survival was similar in patients with de novo AIH compared with the LT population (mean survival time, 17 ± 1.5 vs. 16 ± 0.5 years, Log-rank test; P = 0.4).

CONCLUSIONS

The incidence of de novo AIH is low and does not impact on long-term survival. Recipients of female or older donor grafts, or recipients using tacrolimus, or mycophenolate mofetil as part of their immunosuppressive regimen have a higher risk of de novo AIH, whereas LT recipients maintained on cyclosporine A have a lower risk.

Development and application of a loop-mediated isothermal amplification assay for rapid detection of Borrelia burgdorferi s. l. in ticks

A loop-mediated isothermal amplification (LAMP) assay was developed to detect Borrelia burgdorferi s. l. in ticks, which is a pathogen that causes Lyme disease. Cross-reactions with Chlamydia psittaci, Mycoplasma mycoides subsp. capri and some tick-borne pathogens were excluded. Analytical sensitivity of LAMP showed its detection limit was from 0.02 to 0.2 pg of DNA in detection of the reference samples at 65°C for 40 min. The performance of LAMP was assessed by testing 110 samples from susceptible tick species and comparing the results with conventional and nested PCR tests previously described. The results demonstrated that LAMP was significantly more sensitive than the conventional PCR (32.7% versus 15.5%, P < 0.05) and slightly more sensitive, although not significantly so, than nested PCR (32.7% versus 26.4%, P > 0.05). The assay was used to analyse a total of 1052 ticks collected from eight provinces in China. The results showed that the infection rates of B. burgdorferi s. l. varied from 12.5% to 88.9% across the different geographical sites. Selected positive samples were subjected to sequencing and sequence analysis for conformation of the accuracy of the assay. Here we report a highly sensitive, specific and easy diagnostic assay based on LAMP technology. These data indicate that LAMP is a useful approach for detecting B. burgdorferi s. l. in field-collected ticks and has the potential as an alternative tool for the ecological and epidemiological surveillance of Lyme disease.

Simultaneous detection of piroplasma infections in field Haemaphysalis qinghaiensis ticks by reverse line blotting

Piroplasmosis is caused by tick-borne haemoprotozoan parasites in the genera of Theileria and Babesia, in which numbers of agents are highly pathogenic for cattle, sheep and goats. We developed a reverse line blot (RLB) assay for detection and differentiation of four different parasites, in which 18S ribosomal RNA gene sequence was amplified with a set of universal primers specific for all members in the genera of Theileria and Babesia; and the probes were designed on the basis of hypervariable region 4 (V4 region) of 18S rRNA gene. Three Theileria and one Babesia can be detected simultaneously on this system and it was sensitive to detect a parasitemia level between 10(-5) and 10(-8)%. A total of 149 Haemaphysalis qinghaiensis ticks collected from Lintan County of Gannan Tibetan Autonomous Region was tested by RLB. Among these, 136 tick samples were also tested by a nested PCR assay developed previously. After comparison of these results, it showed that more T. luwenshuni was detected in RLB assay, while more T. uilenbergi was detected in H. qinghaiensis ticks by nested PCR. The RLB has shown capability for simultaneous detection of four species of piroplasm in H. qinghaiensis ticks, indicating its usefulness for epidemiological studies of piroplasmosis.

A facile preparation of novel multifunctional vectors by non-covalent bonds for co-delivery of doxorubicin and gene

In this study, novel multifunctional ternary complexes of biotinylated transferrin-avidin-biotin-poly(ethylene glycol)-poly(L-glutamate acid)/poly(2-(2-aminoethylamino) ethyl methacrylate)/doxorubicin-poly(L-aspartic acid)/pDNA (TAB/PIC-D/pDNA complexes) were prepared based on polyion complex micelles (PIC) and the avidin-biotin system, which aimed to target co-delivery of anti-cancer doxorubicin and gene. Cytotoxicity studies revealed that PIC-D could have anti-tumor effect on HeLa cells and HepG2 cells; TAB coating could increase the biocompatibility of PIC-D/pDNA complexes and the targeting delivery efficiency of doxorubicin. TAB/PIC-D/pDNA complexes possessed higher transfection efficiency than the unmodified complexes in serum, and transferrin could enhance luciferase expression in HeLa cells and HepG2 cells. Furthermore, confocal laser scanning microscopy showed that doxorubicin and gene could be delivered into HepG2 cells simultaneously by TAB/PIC-D/pDNA complexes. The formation of the ternary complexes provides a facile approach to constructing a multifunctional delivery system for targeted co-delivery of anticancer drugs and gene.

Feasibility and safety of stenting for symptomatic carotid arterial dissection

OBJECTIVE

To determine the procedural feasibility and safety of carotid angioplasty and stent placement of carotid artery dissection (CAD) patients who had failed antithrombotic therapy in acute dissection.

METHODS

A series of 33 consecutive patients (mean age, 40.21 years; 29 men and 4 women) who underwent angioplasty and stent placement for symptomatic carotid artery dissection (sCAD) from May 2005 to December 2010 in the Nanjing Stroke Registry Program (NSRP) was retrospectively reviewed. All the included patients had been diagnosed definitively based on catheter angiography, and had failed to respond to medical therapy during the course of initial hospital admission. The baseline and followed up data of these patients were collected and analyzed.

RESULTS

Of all the 33 included patients, 32 patients had achieved technical success without any intraoperative complications. Two patients manifested ipsilateral Horner sign on the next day after stenting, and one of them suffered from recurrence of transient ischaemic attack (TIA) during the course of follow up, but completely remission via antithrombotic therapy.

CONCLUSION

Endovascular stenting is a feasible and safe therapeutic strategy of CAD patients who have failed medical therapy.

Locoregional radiological treatment for hepatocellular carcinoma; Which, when and how?

Hepatocellular carcinoma (HCC) is one of the most frequent and deadliest cancers worldwide. Liver transplantation, surgical resection or local ablation offer the best survival advantages but most patients either present when the tumor is in an advanced stage or the degree of underlying liver disease precludes these options. Several therapies have been proposed for these patients with proven survival benefits. These therapies comprise the locoregional treatment for HCC, and include percutaneous ethanol injection (PEI), radiofrequency ablation (RFA), transarterial chemoembolization (TACE), transarterial radioembolization (TARE), and drug-eluting bead (DEB). PEI and RFA are considered curative treatments for early stage HCC; whereas TACE is a standard of care for intermediate stages. Additionally, evaluation of response to locoregional treatment in HCC is important, as objective response may become a surrogate marker for improved survival. Currently, there are several criteria for response assessment, including the World Health Organization (WHO), the Response Evaluation Criteria in Solid Tumors (RECIST), the European Association for the Study of the Liver Criteria (EASL), and the modified RECIST (mRECIST); however, there has been poor correlation between the clinical benefit provided by locoregional interventional therapies and conventional methods of response assessment. The aim of our study was to review and analyze the current evidence for radiological interventions in HCC, and to propose evidence based recommendations to improve the management of these patients.