Overexpression of nuclear distribution protein (hNUDC) causes pro-apoptosis and differentiation in Dami megakaryocytes

OBJECTIVES

Overexpression of hNUDC, a member of the nuclear distribution protein family, reduces cell population growth in prostate cancer cell lines, concurrent with induced morphological change and enhanced polyploidization. These phenomena are also closely associated with terminal phases of megakaryocyte maturation.

MATERIALS AND METHODS

In Dami cells, MTT and trypan blue assays were used to investigate cell viability and proliferation effects of hNUDC, and flow cytometry was used to analyse cell cycle and DNA content. Real-time RT-PCR was employed to detect mRNA expression. Activations of caspase-3, ERK, Akt and Stat-5 were determined by immunoblotting. May-Grünwald-Giemsa staining was performed to reveal cell morphology.

RESULTS AND CONCLUSION

Functional studies using adenovirus-mediated hNUDC overexpression led to inhibition of megakaryocyte proliferation via cell cycle arrest in G2/M transition phase. This process could have been be mediated by upregulation of p21 and downregulation of its downstream targets, including cyclin B1, cyclin B2 and c-myc. Enhanced apoptosis in turn ensued, characterized by increased caspase-3 activation, upregulation of pro-apoptotic Bax and downregulation of anti-apoptotic Bcl-2. Furthermore, hNUDC overexpression elevated the level of megakaryocyte maturation, associated with increased polyploidy, cell morphological changes and increased expression of cell surface differentiation markers, including CD10, CD44, CD41 and CD61. Our results further suggest that the ERK signalling pathway was involved in hNUDC overexpression-induced apoptosis. Taken together, this study provides experimental evidence for overexpression of hNUDC in Dami cells and suggests that activation of apoptotic machinery may be involved in megakaryocytic differentiation.

Pharmacokinetics, pharmacodynamics, and safety of landiolol hydrochloride in healthy Chinese subjects

OBJECTIVE

Landiolol is an ultra-short-acting β-blocker that appears to be more cardioselective and less toxic than esmolol. The main objective of this study was to investigate the pharmacokinetics, pharmacodynamics, and safety of landiolol hydrochloride in healthy Chinese volunteers.

METHODS

We set 2-dose regimen (L and H groups) [L (low): 0.125 mg/kg/min (1 min) loading→0.02 mg/kg/min (20 min) continuous, H (high): 0.25 mg/kg/min (1 min) loading→0.04 mg/kg/min (20 min) continuous]. 20 healthy subjects of either sex were allocated randomly to the L and H groups (n=10, and 10). Blood samples were collected over 1 h after continuous infusion and were determined using a validated liquid chromatography/mass spectrometry (LC/MS/MS) assay. The safety of landiolol hydrochloride was assessed by adverse events recording, 12-lead ECG findings, physical examination, laboratory testing, and vital signs.

RESULTS

The main pharmacokinetic parameters of landiolol hydrochloride in healthy Chinese subjects were as follows: doses of 2 groups (L and H); Cmax of 400±110 and 731±246 ng/mL; C21min of 327±109 and 508±141 ng/mL; Tmax of 10.1±6.5 and 6.2±5.7 min; t1/2 of 4.7±1.6 and 6.5±1.7 min. Landiolol hydrochloride was safe. There were no adverse events in any subject. The heart rates and blood pressures of subjects administered landiolol hydrochloride decreased, but no clinically significant changes were observed.

CONCLUSION

The concentration of landiolol hydrochloride rapidly reached steady state levels, and rapidly dissipated after completion of administration. Landiolol hydrochloride appears to have rapid onset and short action.

Multi-profile hidden Markov model for mood, dietary intake, and physical activity in an intervention study of childhood obesity

Motivated by an application to childhood obesity data in a clinical trial, this paper describes a multi-profile hidden Markov model (HMM) that uses several temporal chains of measures respectively related to psychosocial attributes, dietary intake, and energy expenditure behaviors of adolescents in a school setting. Using these psychological and behavioral profiles, the model delineates health states from the longitudinal data set. Furthermore, a two-level regression model that takes into account the clustering effects of students within school is used to assess the effects of school-based and community-based interventions and other risk factors on the transition between health states over time. The results from our study suggest that female students tend to decrease their physical activities despite a high level of anxiety about weight. The finding is consistent across intervention and control arms.

Efficient photon management with nanostructures for photovoltaics

Efficient photon management schemes are crucial for improving the energy conversion efficiency of photovoltaic devices; they can lead potentially to reduced material usage and cost for these devices. In this review, photon trapping mechanisms are discussed briefly in the beginning, followed by a summary of recent progress on a number of major categories of nanostructures with intriguing photon management properties. Specifically, nanostructures including nanowires, nanopillars, nanopyramids, nanocones, nanospikes, and so forth, have been reviewed comprehensively with materials including Si, Ge, CdS, CIGS, ZnO, etc. It is found that these materials with diverse configurations have tunable photon management properties, namely, optical reflectance, transmittance and absorption. Investigations on these nanostructures have not only shed light on the fundamental interplay between photons and materials at the nanometer scale, but also suggested a potential pathway for a new generation of photovoltaic devices.

Radiation hybrid QTL mapping of Tdes2 involved in the first meiotic division of wheat

Since the dawn of wheat cytogenetics, chromosome 3B has been known to harbor a gene(s) that, when removed, causes chromosome desynapsis and gametic sterility. The lack of natural genetic diversity for this gene(s) has prevented any attempt to fine map and further characterize it. Here, gamma radiation treatment was used to create artificial diversity for this locus. A total of 696 radiation hybrid lines were genotyped with a custom mini array of 140 DArT markers, selected to evenly span the whole 3B chromosome. The resulting map spanned 2,852 centi Ray with a calculated resolution of 0.384 Mb. Phenotyping for the occurrence of meiotic desynapsis was conducted by measuring the level of gametic sterility as seeds produced per spikelet and pollen viability at booting. Composite interval mapping revealed a single QTL with LOD of 16.2 and r (2) of 25.6 % between markers wmc326 and wPt-8983 on the long arm of chromosome 3B. By independent analysis, the location of the QTL was confirmed to be within the deletion bin 3BL7-0.63-1.00 and to correspond to a single gene located ~1.4 Mb away from wPt-8983. The meiotic behavior of lines lacking this gene was characterized cytogenetically to reveal striking similarities with mutants for the dy locus, located on the syntenic chromosome 3 of maize. This represents the first example to date of employing radiation hybrids for QTL analysis. The success achieved by this approach provides an ideal starting point for the final cloning of this interesting gene involved in meiosis of cereals.

Upregulated Hoxc6 expression is associated with poor survival in gastric cancer patients

Human Hox genes (Homeobox) have crucial roles in development and differentiation, regulating numerous processes including apoptosis, receptor signalling, differentiation, motility and angiogenesis. Aberrant expression of Hoxc6 gene has been reported in several tumor tissues and cancer cell lines. The prognostic significance of Hoxc6 in gastric cancer remains largely unknown.This study was aimed to investigate the clinical significance of Hoxc6 in gastric cancer.Total RNA of paired tissue samples (n=25) and a tissue microarray containing 161 paired tissues from patients with gastric cancers at different stages were collected. Quantitative real-time PCR and immunochemistry assay were carried out to investigate the expression of Hoxc6. Hoxc6 mRNA was increased in gastric cancer tissues ( 16 of 25) compared with the adjacent normal mucosa (P<0.05). Immunohistochemical detection showed that expression of Hoxc6 was associated with the depth of tumor invasion (P<0.05). Patients with higher expression levels of Hoxc6 had a shorter overall survival rate (P<0.05).Hoxc6 might contribute to the progression of gastric carcinogenesis and may be a significant predictor of poor survival in patients with gastric cancer after curative operations.

Development of a novel adenovirus-alphavirus hybrid vector with RNA replicon features for malignant hematopoietic cell transduction

To improve the expression levels of transgenes in malignant hematopoietic cells, we developed a novel adenoviral-alphavirus hybrid vector Ad5/F11p-SFV-GFP that contains a Semliki Forest Virus (SFV) replicon and chimeric fibers of Ad5 and Ad11p. Ad5/F11p-SFV-GFP infected >95% of K562, U937 or Jurkat cells and 23.65% of HL-60 cells, and led to moderate Enhanced Green Fluorescent Protein (EGFP) transgene expression intensity. The infection efficiency of Ad5/F11p-SFV-GFP in primary human leukemia cells ranged from 9.34-89.63% (median, 28.58%) at a multiplicity of infection (MOI) of 100, compared with only 3.37-44.54% (median, 10.42%) in cells infected by Ad5/F11p-GFP. Importantly, Ad5/F11p-SFV-GFP led to a significantly higher transgene expression level in primary leukemia cells, as indicated by the relative fluorescence intensity, compared to cells infected with Ad5/F11p-GFP. The increased expression of EGFP in Ad5/F11p-SFV-GFP-infected cells was associated with the accumulation of abundant subgenomic mRNA. Additionally, infection of K562, U937 or Jurkat cells by Ad5/F11p-SFV-GFP was significantly inhibited by blocking CD46 receptor; however, other factors may affect the gene-transfer efficiency of Ad5/F11p-SFV-GFP in primary leukemia cells. In conclusion, we successfully developed a novel adenoviral-alphavirus hybrid vector with RNA replicon features, which represents a promising vector for gene modifications during the production of cell-based vaccines for leukemia patients.

Growth factor receptor-bound protein 10-mediated negative regulation of the insulin-like growth factor-1 receptor-activated signalling pathway results in cognitive disorder in diabetic rats

Growth factor receptor-bound protein 10 (Grb10) is a Src homology 2 domain-containing protein and one of the binding partners for several transmembrane tyrosine kinase receptors, including insulin receptor (IR) and insulin-like growth factor-1 receptor (IGF1-R). The hippocampus, which is critical for cognitive functions, is one of the main distribution areas of Grb10 in the central nervous system. In recent years, diabetic encephalopathy has been defined as a third type of diabetes and the IGF1-IR pathway was shown to be critical for the neuropathogenic process of cognitive disorder in diabetes. However, the role of endogenous Grb10 in regulating the IGF1-IR pathway and neurobehavioural changes is not explicit. The present study aimed to determine the in vivo function of endogenous Grb10 in diabetic encephalopathy and the underlying mechanisms. Using stereotaxic surgical techniques and lentiviral vectors expressing specific short hairpin RNA, we could steadily knockdown Grb10 expression in the hippocampus. More importantly, we demonstrated that hippocampus-specific modulation of Grb10 protein levels led to a prominent remission of cognitive disorder, including improvements in both ultrastructural pathology and abnormal neurobehavioural changes. Our findings indicate that endogenous overexpression of Grb10 functions as a suppressor of the IGF1-IR pathway, which may represent an important mechanism for regulating cognitive disorder in diabetes.

Comparison of the safety and efficacy of conventional monopolar and 2-micron laser transurethral resection in the management of multiple nonmuscle-invasive bladder cancer

Objectives

To compare the safety and efficacy of conventional monopolar transurethral resection of bladder tumour (TURBT) and 2-micron continuous-wave laser resection (2-µm laser) techniques in the management of multiple nonmuscle-invasive bladder cancer (NMIBC), and to investigate long-term effects on tumour recurrence.

Methods

Patients with multiple NMIBC were randomized to receive TURBT or 2-µm laser in a nonblinded manner. All patients received intravesical chemotherapy with epirubicin (40 mg/40 ml) for 8 weeks, beginning 1 week after surgery, followed with monthly maintenance therapy for 12 months. Three-year follow-up data of preoperative, operative and postoperative management were recorded.

Results

In total, 120 patients were included: 56 in the TURBT group and 64 in the 2-µm laser group. Intra- and postoperative complications (including bladder perforation, bleeding and irritation) were less frequently observed in the 2-µm laser group compared with the TURBT group. There were no significant differences in first time to recurrence, overall recurrence or occurrence of urethral strictures.

Conclusions

The 2-µm laser resection method was more effective than TURBT in reducing rates of intra- and postoperative complications, but offered no additional benefit regarding tumour recurrence.

Prevalence and risk factors of asymptomatic intracranial arterial stenosis in a community-based population of Chinese adults

BACKGROUND AND PURPOSE

Intracranial arterial stenosis (ICAS) is one of the most common causes of ischaemic stroke in Asia. Knowledge of the prevalence and risk factors of asymptomatic ICAS is limited. The prevalence of ICAS was therefore investigated and its risk factors in a Chinese community-based population were explored.

METHODS

From 2010 to 2011, a stratified (by sex and age) random sample of 5440 participants aged 40 years or older were enrolled in the study. ICAS was assessed using transcranial Doppler. Logistic regression was used to evaluate potential risk factors associated with ICAS in participants.

RESULTS

In total, 13.2% (95% CI 12.3-14.1) of the subjects had ICAS, and women were more likely than men to have ICAS in the 40-49 year age group. Hypertension [odds ratio (OR) = 2.23, 95% CI 1.87-2.66], diabetes (OR = 1.99, 95% CI 1.62-2.45), left ventricular hypertrophy (OR = 1.66, 95% CI 1.18-2.34) and elevated high-sensitivity C-reactive protein (OR = 1.55, 95% CI 1.19-2.02) were independently associated with higher prevalence of ICAS after adjusting for age, gender, body mass index, smoking status and other covariates. Of the 716 ICAS individuals, 90.6% had one or more of these risk factors. Amongst the subjects who had at least one risk factor, 15.2% had ICAS.

CONCLUSIONS

Intracranial artery stenosis is common in the Chinese population. Individuals who had one or more risk factors were more likely to have ICAS, suggesting more aggressive risk factor management.

Effects of Process Conditions on the Dissolution of Carbon Dioxide in PS in Foaming Extruders

The effects of the main processing conditions on the dissolution behavior of CO2 in polystyrene melt were studied using a novel in-line method in connection with both single and twin-screw foaming extruders. Apparent solubility data obtained from the twin-screw extrusion experiments showed better consistency compared with those obtained from the single screw experiments, indicating the importance of enhanced mixing in affecting the gas dissolution and solubility behavior during an extrusion foaming process. Gas dissolution inside a twin-screw foaming extruder was further studied for CO2 in the polystyrene melt. The measured gas up-take was compared with the values calculated assuming equilibrium conditions in the gas injection zone in an effort to elucidate possible mechanisms for gas dissolution inside a foaming extruder during the actual foaming process.