Transformation of electronic properties and structural phase transition from HfN to Hf3N4

We report investigation of the structural phase transition and electronic properties of Hf(1-x)N (0 ⩽ x ⩽ 0.25) using first principles calculations. The defective NaCl-type structure with Hf vacancies (V(Hf)) is found to be stable over a large phase region. Hf3N4 with the Zr3N4-type structure is only stable in relative small region and readily destabilized when the stoichiometric ratio of N to Hf deviates from 4/3. The electronic and optic properties of Hf(1-x)N are controlled by the concentration of V(Hf). The full depletion of excess free electrons from Hf atoms results in the structural phase transition of Hf3N4.

Cu₄ Cluster Doped Monolayer MoS₂ for CO Oxidation

The catalytic oxidation of CO molecule on a thermodynamically stable Cu₄ cluster doped MoS₂ monolayer is investigated by density functional theory (DFT) where the reaction proceeds in a new formation order of COOOCO* (O₂* + 2CO* → COOOCO*), OCO* (COOOCO* → CO₂ + OCO*), and CO₂ (OCO* → CO₂) desorption with the corresponding reaction barrier values of 0.220 eV, 0.370 eV and 0.119 eV, respectively. Therein, the rate-determining step is the second one. This low barrier indicates high activity of this system where CO oxidation could be realized at room temperature (even lower). As a result, the Cu₄ doped MoS₂ could be a candidate for CO oxidation with lower cost and higher activity without poisoning and corrosion problems.

Screening for and treatment of osteoporosis: construction and validation of a state-transition microsimulation cost-effectiveness model

This study aimed to document and validate a new cost-effectiveness model of osteoporosis screening and treatment strategies. The state-transition microsimulation model demonstrates strong internal and external validity. It is an important tool for researchers and policy makers to test the cost-effectiveness of osteoporosis screening and treatment strategies.

INTRODUCTION

The objective of this study was to document and validate a new cost-effectiveness model of screening for and treatment of osteoporosis.

METHODS

A state-transition microsimulation model using a lifetime horizon was constructed with seven Markov states (no history of fractures, hip fracture, vertebral fracture, wrist fracture, other fracture, postfracture state, and death) describing the most important clinical outcomes of osteoporotic fractures. Tracker variables were used to record patients' history, such as fracture events, duration of treatment, and time since last screening. The model was validated for Chinese postmenopausal women receiving screening and treatment versus no screening. Goodness-of-fit analyses were performed for internal and external validation. External validity was tested by comparing life expectancy, osteoporosis prevalence rate, and lifetime and 10-year fracture risks with published data not used in the model.

RESULTS

The model represents major clinical facets of osteoporosis-related conditions. Age-specific hip, vertebral, and wrist fracture incidence rates were accurately reproduced (the regression line slope was 0.996, R(2) = 0.99). The changes in costs, effectiveness, and cost-effectiveness were consistent with changes in both one-way and probabilistic sensitivity analysis. The model predicted life expectancy and 10-year any major osteoporotic fracture risk at the age of 65 of 19.01 years and 13.7%, respectively. The lifetime hip, clinical vertebral, and wrist fracture risks at age 50 were 7.9, 29.8, and 18.7% respectively, all consistent with reported data.

CONCLUSIONS

Our model demonstrated good internal and external validity, ensuring it can be confidently applied in economic evaluations of osteoporosis screening and treatment strategies.

Mutation of the rice ASL2 gene encoding plastid ribosomal protein L21 causes chloroplast developmental defects and seedling death

The plastid ribosome proteins (PRPs) play important roles in plastid protein biosynthesis, chloroplast differentiation and early chloroplast development. However, the specialised functions of individual protein components of the chloroplast ribosome in rice (Oryza sativa) remain unresolved. In this paper, we identified a novel rice PRP mutant named asl2 (Albino seedling lethality 2) exhibiting an albino, seedling death phenotype. In asl2 mutants, the alteration of leaf colour was associated with chlorophyll (Chl) content and abnormal chloroplast development. Through map-based cloning and complementation, the mutated ASL2 gene was isolated and found to encode the chloroplast 50S ribosome protein L21 (RPL21c), a component of the chloroplast ribosome large subunit, which was localised in chloroplasts. ASL2 was expressed at a higher level in the plumule and leaves, implying its tissue-specific expression. Additionally, the expression of ASL2 was regulated by light. The transcript levels of the majority of genes for Chl biosynthesis, photosynthesis and chloroplast development were strongly affected in asl2 mutants. Collectively, the absence of functional ASL2 caused chloroplast developmental defects and seedling death. This report establishes the important role of RPL21c in chloroplast development in rice.

The protective effect of huperzine A against hepatic ischemia reperfusion injury in mice

BACKGROUND

Nowadays, hepatic ischemia reperfusion (HI/R) injury is regarded as a serious concern in clinical practices. Huperzine A (HupA) is an alkaloid isolated from the Chinese folk medicine huperzia serrate, which has possessed diverse pharmacological actions.

METHODS

A mouse model of HI/R was caused by clamping the hepatic artery, the hepatoportal vein, and the bile duct with a vascular clamp for 30 minutes followed by reperfusion for 6 hours under anesthesia. The sham group experienced the identical procedure without hepatic ischemia. The HupA group received an injection into the tail vein 5 minutes prior to HI/R at the doses of 167 and 500 μg/kg. The vehicle group was injected with physiological saline instead of HupA. The liver function was assessed by determinations of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities. Tissue levels of superoxide dismutase (SOD), catalase (CAT), malondiadehyde (MDA), and glutathione (GSH) were also measured spectrophotometrically. In addition, the activities of hepatic inflammatory mediators such as nuclear factor kappa B (NF-κB) p65, tumor necrosis factors-α (TNF-α, interleukin-1β (IL-1β) and IL-6 were also measured. Furthermore, the apoptotic damage was evaluated by measuring caspase-3 activity in hepatic tissues.

RESULTS

Treatment with HupA in mice at the doses of 167 and 500 μg/kg remarkably reduced serum ALT and AST activities in HupA-treated ischemic mice. Furthermore, HupA treatment could enhance the activities of hepatic tissue SOD, CAT, and GSH but decrease MDA tissue content. The activities of inflammatory cytokines including NF-κB p65, TNF-α, IL-1β and IL-6 were all decreased in ischemic mice treated with HupA. Colorimetric test results illustrated that a marked reduction of caspase-3 activity was found in the HupA-treated group compared with the vehicle group.

CONCLUSION

Our present data suggest that HupA has a protective role against HI/R injury of mice and antioxidative, anti-inflammatory, and antiapoptotic actions are involved in its protection.

DFT study of CO oxidation on Cu2O–Au interfaces at Au–Cu alloy surfaces

CO oxidation on the Cu₂O–Au interface at Au–Cu alloy surfaces.

Presence of CD34(+)CD38(-)CD58(-) leukemia-propagating cells at diagnosis identifies patients at high risk of relapse with Ph chromosome-positive ALL after allo-hematopoietic SCT

Relapse of Ph chromosome-positive ALL (Ph(+)ALL) results from the persistence of leukemia-propagating cells (LPCs). In Ph(+)ALL, a xenograft assay recently determined that LPCs are enriched in the CD34(+)CD38(-)CD58(-) fraction. Therefore, the prognostic significance of LPCs in Ph(+)ALL subjects after allogeneic hematopoietic SCT (allo-HSCT) was investigated. A total of 80 consecutive adults with Ph(+)ALL who underwent allo-HSCT were eligible. A multi-parameter flow cytometry analysis examining CD58-FITC/CD10-PE/ CD19-APC-Cy7/CD34-PerCP/CD45-Vioblue/ CD38-APC on gated leukemia BM blasts was performed at diagnosis. Based on the original blast phenotypes, subjects were stratified into the CD34(+)CD38(-)CD58(-)group (N=15) and other phenotype group (N=65). During minimal residual disease monitoring, significantly higher levels of BCR/ABL transcripts were detected in subjects in the CD34(+)CD38(-)CD58(-) group than in other phenotype group, especially at 3 months post HSCT. In addition, CD34(+)CD38(-)CD58(-)LPCs are directly correlated with a higher 3-year cumulative incidence of relapse (CIR) and worse leukemia-free survival (LFS) and OS. Multivariate analyses indicated that presence of CD34(+)CD38(-)CD58(-) LPCs at diagnosis, and BCR-ABL reduction at 3 months post HSCT were independent risk factors for relapse, LFS and OS. Our data suggest that presence of CD34(+)CD38(-)CD58(-) LPCs at diagnosis allows rapid identification of high-risk patients for relapse after allo-HSCT.

Cloning and sequence analysis of the Blumea balsamifera DC farnesyl diphosphate synthase gene

Blumea balsamifera DC is a member of the Compositae family and is frequently used as traditional Chinese medicine. Blumea balsamifera is rich in monoterpenes, which possess a variety of pharmacological activities, such as antioxidant, anti-bacteria, and anti-viral activities. Farnesyl diphosphate synthase (FPS) is a key enzyme in the biosynthetic pathway of terpenes, playing an important regulatory role in plant growth, such as resistance and secondary metabolism. Based on the conserved oligo amino acid residues of published FPS genes from other higher plant species, a cDNA sequence, designated BbFPS, was isolated from B. balsamifera DC using polymerase chain reaction. The clones were an average of 1.6 kb and contained an open reading frame that predicted a polypeptide of 342 amino acids with 89.07% identity to FPS from other plants. The deduced amino acid sequence was dominated by hydrophobic regions and contained 2 highly conserved DDxxD motifs that are essential for proper functioning of FPS. Phylogenetic analysis indicated that FPS grouped with other composite families. Prediction of secondary structure and subcellular localization suggested that alpha helices made up 70% of the amino acids of the sequence.

Personal inhalation exposure to polycyclic aromatic hydrocarbons in urban and rural residents in a typical northern city in China

Personal inhalation exposure samples were collected and analyzed for polycyclic aromatic hydrocarbons (PAHs) for 126 selected volunteers during heating and non-heating seasons in a typical northern Chinese city, Taiyuan. Measured personal PAH exposure levels for the urban residents in the heating and non-heating seasons were 690 (540-1051) and 404 (266-544) ng/m(3) , respectively, while, for the rural residents, they were 770 (504-1071) and 312 (201-412) ng/m(3) , respectively. Thus, rural residents are exposed to lower PAH contamination in comparison with the urban residents in the non-heating seasons. In the heating season, personal PAH inhalation exposure levels were comparable between the urban and rural residents, in part owing to the large rate of residential solid fuel consumption in the rural area for household cooking and heating. The estimated incremental lifetime cancer risks (ILCR) due to PAH exposure in Taiyuan were 3.36 × 10(-5) and 2.39 × 10(-5) for the rural and urban residents, respectively, significantly higher than the literature-reported national average level, suggesting an urgent need of PAH pollution control to protect human health.

Characteristics of spermatogonial stem cells derived from neonatal porcine testis

The aim of this study was to isolate and characterise porcine spermatogonial stem cells (PSSCs). The putative porcine germline stem cells from testis were isolated successfully by an improving way of enrichment with lymphocyte separation medium (LSM). Results from RT-PCR analyses showed that PSSCs were positive for OCT4, SOX2, NANOG, PGP9.5, c-MYC, KEL4 and PRDM-14 which are multipotent stem cell markers. At the protein level, the results of immunofluorescence analyses showed that PSSCs were positive for OCT4, PGP9.5, SOX2 and CD29. We successfully differentiated these PSSCs into adipocytes and muscle cells and then defined their characteristics, including morphology, surface stem cell markers, and mechanical properties. But the experiment of teratoma formation was negative. The results indicated the PSSCs could be multipotent. Atomic force microscopy was used to characterise the morphological and mechanical properties of undifferentiated PSSCs, as well as the differentiated adipocytes and muscle cells, which could be potentially useful for distinguishing PSSCs from differentiated cells.

Haploidentical hematopoietic SCT may be superior to conventional consolidation/maintenance chemotherapy as post-remission therapy for high-risk adult ALL

Only 30% of high-risk adult ALL patients in their first complete remission (CR1) are able to receive an HLA-matched sibling stem cell transplant. The role of haploidentical hematopoietic SCT (haplo-HSCT) in post-remission therapy is not well established. Recently, we developed a novel protocol for unmanipulated haploidentical transplantation. In this study, we compared haplo-HSCT with conventional consolidation and maintenance chemotherapy in adult high-risk ALL patients. Between January 2000 and December 2012, 104 patients received conventional chemotherapy and 79 patients received haplo-HSCT. Patients who underwent haplo-HSCT had significantly improved 3-year OS (72.5% vs 26.6%; P<0.001), 3-year disease-free survival (DFS) (63.9% vs 21.1%; P<0.001) and 3-year relapse (18.7% vs 60.5%; P<0.001) rates. The non-relapse mortality (NRM) rate was not different between patients treated with haplo-HSCT vs chemotherapy (19.2% vs 14.4%; P=0.80). In multivariate analysis, the only factor associated with improved OS, better DFS and low risk of relapse was haplo-HSCT. The only factor associated with high NRM was enrollment before 2006. In conclusion, haplo-HSCT may be an option for adults with high-risk ALL in CR1 who do not have an HLA-matched donor.

Paediatric pseudoxanthoma elasticum with cardiovascular involvement

BACKGROUND

Pseudoxanthoma elasticum (PXE) is characterized by aberrant mineralization of connective tissues, causing considerable morbidity and mortality. The disease is typically of late onset, the skin manifestations first being noted in the teens or later. Another aberrant mineralization disorder, generalized arterial calcification of infancy (GACI), is present at birth and can demonstrate a phenotypic overlap with PXE.

OBJECTIVES

A patient with PXE was noted to have skin findings as early as at 6 years of age, with cardiovascular involvement. The purpose of this study was to examine the genetic basis of this phenotypic presentation in the spectrum of PXE/GACI.

METHODS

The patient's genotype was studied by sequencing ABCC6 and ENPP1, genes known to be associated with PXE and/or GACI.

RESULTS

Screening of the ABCC6 gene revealed two pathogenetic mutations, p.R1141X and g.del23-29. Analysis of the ENPP1 gene failed to demonstrate the presence of mutations.

CONCLUSIONS

This study demonstrates the presence of cutaneous findings of PXE in an 8-year-old paediatric patient, with cardiovascular involvement, illustrating the phenotypic spectrum of PXE.

Involvement of p38 in signal switching from autophagy to apoptosis via the PERK/eIF2α/ATF4 axis in selenite-treated NB4 cells

Selenite has emerged as an optional chemotherapeutic agent for hematological malignancies. Autophagy and apoptosis are both engaged in selenite-induced cell death. In a previous report, we have identified heat shock protein 90 (Hsp90) as a critical modulator of the balance between autophagy and apoptosis in selenite-treated leukemia cells. However, the mechanisms by which selenite mediates the crosstalk between autophagy and apoptosis remain largely unknown. Herein, we demonstrate that the endoplasmic reticulum (ER) stress-related PERK/eIF2α/ATF4 pathway and p38 are core modules for the selenite-induced switch to apoptosis from autophagy. We found that selenite activated PERK and eIF2α/ATF4 downstream to promote apoptosis. During this progression, p38 was dissociated from PERK-inhibiting Hsp90 and became autophosphorylated. Then, activated p38 further enhanced the docking of activating transcription factor 4 (ATF4) onto the CHOP (CCAAT/enhancer-binding protein homologous protein) promoter via eIF2α to enhance apoptosis. We also found that activated p38 suppressed the phosphorylation of eIF4E that directed ATF4 to bind to the MAP1LC3B (microtubule-associated protein 1 light chain 3B) promoter. Because of the deactivation of eIF4E, the association of ATF4 with the MAP1LC3B promoter was inhibited, and autophagy was compromised. Intriguingly, p53 played important roles in mediating the p38-mediated regulation of eIF2α and eIF4E. When activated by p38, p53 induced the phosphorylation of eIF2α and the dephosphorylation of eIF4E, particularly in the nucleus where the ATF4 transcription factor was modulated, ultimately resulting in differential expression of CHOP and LC3. Moreover, selenite exhibited potent antitumor effects in vivo. In an NB4 cell xenograft model, selenite induced apoptosis and hampered autophagy. In addition, related signaling proteins demonstrated similar changes to those observed in vitro. These data suggest that selenite may be a candidate drug for leukemia therapy.

Serological and virological surveillance of avian influenza A virus H9N2 subtype in humans and poultry in Shanghai, China, between 2008 and 2010

We report the serological evidence of low-pathogenic avian influenza (LPAI) H9N2 infection in an occupational poultry-exposed population and a general population. A serological survey of an occupational poultry-exposed population and a general population was conducted using a haemagglutinin-inhibiting (HI) assay in Shanghai, China, from January 2008 to December 2010. Evidence of higher anti-H9 antibodies was found in serum samples collected from poultry workers. During this period, 239 H9N2 avian influenza viruses (AIVs) were isolated from 9297 tracheal and cloacal paired specimens collected from the poultry in live poultry markets. In addition, a total of 733 influenza viruses were isolated from 1569 nasal and throat swabs collected from patients with influenza-like symptoms in a sentinel hospital, which include H3N2, H1N1, pandemic H1N1 and B, but no H9N2 virus was detected. These findings highlight the need for long-term surveillance of avian influenza viruses in occupational poultry-exposed workers.

MRI evaluation of BBB disruption after adjuvant AcSDKP treatment of stroke with tPA in rat

The primary limitation of thrombolytic treatment of ischemic stroke with tissue plasminogen activator (tPA) is the hemorrhagic risk. We tested AcSDKP (N-acetyl-seryl-aspartyl-lysyl-proline), as an auxiliary therapeutic agent, to reduce blood-brain barrier (BBB) disruption in a combination tPA thrombolytic treatment of stroke. Wistar rats subjected to embolic stroke were randomly assigned to either the tPA monotherapy group (n=9) or combination of tPA and AcSDKP treatment group (n=9) initiated at 4 h after ischemia. Magnetic resonance imaging (MRI) measurements were performed before and after the treatments. Immunohistochemical staining and measurements were performed to confirm MRI findings. Longitudinal MRI permeability measurements with gadolinium-diethylenetriamine penta-acetic acid (Gd-DTPA) demonstrated that combination treatment of acute embolic stroke with AcSDKP and tPA significantly reduced BBB leakage, compared to tPA monotherapy, at 3 and 6 days (18.3±9.8 mm3 vs. 65.0±21.0 mm3, p<0.001) after the onset of stroke, although BBB leakage was comparable between the two groups prior to the treatments (6.8±4.4 mm3 vs. 4.3±3.3 mm3, p>0.18). The substantial reduction of BBB leakage observed in the combination treatment group was closely associated with reduced ischemic lesions measured by T2 maps (113.6±24.9 mm3 vs. 188.1±60.8 mm3, p<0.04 at 6 days). Histopathological analysis of the same population of rats showed that the combination treatment significantly reduced parenchymal fibrin deposition (0.063±0.059 mm2 vs. 0.172±0.103 mm2, p<0.03) and infarct volume (146.7±35.9 mm3 vs. 199.3±60.4 mm3, p<0.05) compared to the tPA monotherapy at 6days after stroke. MRI provides biological insight into the therapeutic benefit of combination treatment of stroke with tPA and AcSDKP 4h after onset, and demonstrates significantly improved cerebrovascular integrity with neuroprotective effects compared with tPA monotherapy.

CD58, a novel surface marker, promotes self-renewal of tumor-initiating cells in colorectal cancer

Colorectal tumor-initiating cells (CT-ICs) have self-renewal capabilities and have an important role in tumorigenesis, metastasis, recurrence and treatment resistance in colorectal cancer. Multiple cell-surface molecules targeting CT-ICs, possibly representing different CT-IC subpopulations, have been reported. However, whether new surface markers exist, as well as the mechanisms by which the markers regulate self-renewal, remain unclear. In this study, we enriched a CT-IC population through a serum-free low-adhesion system in vitro. Within this population, we found that CD58 and CD44 were upregulated using a cDNA GeneChip, and CD44(high)CD58(high) cancer cells, the common existence of which was demonstrated by flow cytometry in multiple colon cancer cell lines and primary specimens, exhibited enhanced self-renewal ability, epithelial-mesenchymal transition ability and tumorigenicity, both in vitro and in vivo. Furthermore, activated CD58 upregulated the Wnt/β-catenin pathway and thus promoted self-renewal of CT-ICs; conversely, knockdown of CD58 significantly impaired sphere formation and tumor growth. With immunoprecipitation and western blotting approaches, CD58 was found to upregulate the Wnt pathway by degradation of Dickkopf 3. These results indicate that CD58 is a novel cell-surface marker that functionally regulates self-renewal of CT-ICs, which may provide an intriguing therapeutic target for the efficient killing and elimination of CT-ICs.

Comparison of long-term and short-term administration of itraconazole for primary antifungal prophylaxis in recipients of allogeneic hematopoietic stem cell transplantation: a multicenter, randomized, open-label trial

BACKGROUND

The optimal agents and duration of primary antifungal prophylaxis in recipients of allogeneic hematopoietic stem cell transplantation (allo-HSCT) remain a matter of discussion.

OBJECTIVE

Our objective was to compare the efficacy and safety of long-term and short-term administration of itraconazole (ITCZ) for primary antifungal prophylaxis in allo-HSCT recipients.

METHODS

This multicenter, randomized, open-label pilot study was performed in 4 transplant centers in China. Recipients of allo-HSCT without a history of invasive fungal disease (IFD) were randomly assigned to the long-term or the short-term arm. Randomization was carried out by a center computer system. Intravenous ITCZ was given to the patients in both study arms with a loading dose of 400 mg/day for 2 days followed by 200 mg/day until day +14 or when the white blood cell count was >1.0 × 10(9) /L, and then switched to oral ITCZ solution; prophylaxis was continued until day +30 post transplantation in the short-term arm or until day +90 in the long-term arm. The trough serum concentrations of ITCZ also were measured. The primary study endpoint was the incidence of IFD (proven, probable, and possible) within day +90 post transplantation.

RESULTS

A total of 128 recipients were enrolled in this study; 59 of them were randomized to the long-term arm and 62 were randomized to the short-term arm, forming the modified intent-to-treat (mITT) set. The incidence of IFD within day +90, the primary endpoint, was not significantly different between the 2 arms for the mITT set (6.78% in the long-term arm vs. 6.45% in the short-term arm, P = 0.94), or for the per-protocol set (6.90% in the long-term arm vs. 6.67% in the short-term arm, P = 0.96). From day +30 to day +90, the incidence of IFD was 0% and 6.45%, respectively, in the patients with long-term and short-term prophylaxis for the mITT set (P = 0.11). The mean trough serum concentrations of ITCZ was maintained at >500 ng/mL throughout administration. The incidences of withdrawal because of drug-related adverse events in patients with long-term and short-term prophylaxis were 6.78% and 0%, respectively (P = 0.05).

CONCLUSIONS

Long-term and short-term administration of ITCZ both seemed effective in preventing IFD in recipients of allo-HSCT. Further study with large sample size should be performed to evaluate this result. ITCZ shows the same pharmacokinetics in recipients of allo-HSCT as in non-recipients.

Holmium:YAG laser ablation combined intraurethral fluorouracil perfusion as treatment option for intraurethral Condyloma acuminata in men

AIM

Intraurethral condylomata acuminata (CA) is caused by human papilloma virus (HPV) infection which is transmitted by close physical and sexual contact. CA is often difficult to cure. There is limited research on the treatment of the patients with intraurethral CA. Here, we have reviewed our experiences on the treatment of intraurethral condylomatous with Holmium:YAG Laser ablation. A new and convenient mean of administering fluorouracil and lidocaine for the treatment of intraurethral condyloma acuminata is discussed. This study aimed to evaluate the experience and efficacy of Holmium:YAG Laser ablation with ureteroscopy and local administration of fluorouracil in the treatment of patients with intraurethral CA. The effects were investigated based on the rate of cure and relapse and the incidence of complications.

METHODS

The study included patients with intraurethral condylomatous who had undergone Holmium:YAG Laser ablation and intraurethral perfusion of fluorouracil. From May 2005 to October 2008, 25 patients (mean age 31.3 years, 19-63 years) with cystourethroscopy confirmed extensive lesions at the anterior urethra and biopsy of the lesions was compatible with condyloma acuminata. They all underwent Holmium:YAG Laser ablation with a transurethral Wolf 8/9.8 Fr rigid ureteroscope. And a week later, the patients initially accepted intraurethral installation of the mixture containing 1% fluorouracil and 1% tetracaine hydrochloride gel (lubricating jelly) in a volume of 20 mL. This mixture was given intraurethrally once weekly, and tip of the penis was clamped immediately to close the urethral meatus after administration by using an occlusive penile clamp and was retained for 20 minutes. Six treatments were given initially and after six weeks of rest, another cycle of six weekly treatments was given.

RESULTS

Ureteroscopic Holmium laser ablation was successfully performed in all patients with multifocal intraurethral CA. Mean CA warts body size was 3 mm (2-8) in diameter. Mean operative time was 22.8 minutes (range 13-41). No major intraoperative complications occurred. Intraurethral installation was well tolerated, although six patients complained occasional urethral pain while urinating. Three relapses in a 2-5 weeks of follow-up underwent repeat holmium laser ablation and installation of the fluorouracil mixture. In an average of six months of follow-up, the patients have no ureteral stricture or relapse of the CA.

CONCLUSION

The results of this study suggest that holmium:YAG laser ablation of the intraurethral CA combined with intraurethral perfusion of 5-fluorouracil and tetracaine hydrochloride gel mixture is an effective and safer therapy with a lower relapse rate for treatment of intraurethral CA.

Molecular imaging of pancreatic islet transplantation

Islet replacement therapy, pancreatic islet transplantation, is considered as a potential option for curing T1DM. However, the significant loss of implanted islets after islet transplantation prevents it from becoming a mainstream treatment modality. Due to the lack of reliable noninvasive real-time imaging techniques to track the survival of the islets, it is impossible to discover the specific causes for the loss of implanted islets, not to mention taking interventions in the early stage. Current achievements in molecular imaging has provided with several promising techniques, including optical imaging, PET and MRI, for noninvasive visualization, quantification and functional evaluation of transplanted islets in experimental conditions. Optical imaging seems to be the most convenient and cost-efficient modality, but the limited penetration distance hinders its application in large animal and human studies. PET combined with target-specific tracers is characterized by high specificity and sensitivity for detection of islet grafts, but observation time is rather short (i.e., several hours). MRI stands out for its long-term visualization of transplanted islet grafts with the aid of contrast agents. However, quantification of islets remains a problem to be solved. A novel technique, microencapsulation, provides a new perspective in multimodal imaging by optimizing the strengths of several modalities together. Although the application of molecular imaging in clinical settings is still limited, significant success and valuable information is achieved in the basic and clinical trials. However, islet transplantation still remains an experimental procedure, with ongoing researches focusing on islets availability, appropriate sites for implantation, new methods using biomaterials (e.g. microencapsulation), immune modulation and more.

Health-related quality of life of patients with newly diagnosed chronic myeloid leukemia treated with allogeneic hematopoietic SCT versus imatinib

To evaluate and compare the health-related quality of life (HRQOL) of patients with newly diagnosed CML in the first chronic phase (CML-CP1) receiving HLA-identical sibling donor (ISD) hematopoietic SCT (HSCT) or imatinib, a cross-sectional study that was part of a prospective cohort study at the Institute of Hematology, Peking University was performed. A total of 222 patients including 126 and 96 in the imatinib and ISD HSCT groups, respectively, were enrolled. HRQOL was measured using the Medical Outcomes Study 36-Item Short-Form Health Survey. The ISD HSCT group functioned significantly better on the role-physical functioning and mental health subscales, as well as the mental component summary (MCS) than the imatinib group. HRQOL was generally comparable to groups in the young population. Multivariate analysis showed that white blood cell count ≥ 30 × 10(9)/L and plts count ≥ 450 × 10(9)/L were the major adverse factors affecting HRQOL in long-term survivors. Imatinib therapy was also an adverse factor affecting the MCS (odds ratio=1.7, P=0.032). Thus, long-term CML-CP1 survivors receiving ISD HSCT can attain desirable HRQOL comparable to or better than that of patients receiving imatinib.

Tunable band gaps in silicene–MoS2heterobilayers

A sizable and tunable bandgap is realized in silicene–MoS₂heterobilayers.

Phase stability and elastic properties of (W0.5Al0.5)C phase with a novel NiAs-type structure

Using density-functional theory, we show that the NiAs-type is a more favorable structure for the (W_0.5Al_0.5)C phase than the experimentally proposed WC-type structure when we compare the thermodynamic, dynamic and elastic properties of the two types.

Curvature effect of SiC nanotubes and sheets for CO2capture and reduction

CO₂adsorption and reduction on SiC nanomaterials display a curvature effect.

Propensity for social interaction predicts nicotine-reinforced behaviors in outbred rats

Social and genetic factors can influence smoking behavior. Using olfactogustatory stimuli as the sensory cue for intravenous nicotine self-administration (SA), we previously showed that social learning of nicotine contingent odor cue prevented rats from developing conditioned taste aversion and allowed them to instead establish stable nicotine SA. We hypothesized that genetic factors influenced socially acquired nicotine SA. A heterogeneous stock (HS; N/NIH) of outbred rats was trained to self-administer nicotine using the social learning protocol. Both male and female HS rats acquired nicotine SA, but females self-administered more nicotine than males. After extinction, the context previously paired with nicotine SA, in conjunction with socially transmitted drug cues, was sufficient to cause reinstatement of drug-seeking behavior. Wide variation in both nicotine intake and reinstatement was observed. Using multiple regression analysis, we found that measures of social interaction were significant predictors of nicotine intake and reinstatement of drug seeking in both males and females. Furthermore, measures of depression were predictors of nicotine intake in both males and females, anxiety was a predictor only in males and response to novelty was a predictor only in females. In males, measures of both depression and anxiety predicted nicotine reinstatement. Together, these data supported the ideas that genetically determined propensities for emotional and social phenotypes are significant determinants for nicotine-reinforced behavior, and that the HS rat is a suitable tool for dissecting genetic mechanisms that may underlie the interaction between social behavior, anxiety, depression and smoking.

Asymmetric dimethylarginine attenuates serum starvation-induced apoptosis via suppression of the Fas (APO-1/CD95)/JNK (SAPK) pathway

Asymmetric dimethylarginine (ADMA) is synthesized by protein arginine methyltransferases during methylation of protein arginine residues and released into blood upon proteolysis. Higher concentrations of ADMA in blood have been observed in patients with metabolic diseases and certain cancers. However, the role of ADMA in colon cancer has not been well investigated. ADMA serum levels in human patients diagnosed with colon cancer were found to be higher than those present in healthy subjects. ADMA treatment of LoVo cells, a human colon adenocarcinoma cell line, attenuated serum starvation-induced apoptosis and suppressed the activation of the Fas (APO-1/CD95)/JNK (SAPK) (c-Jun N terminal protein kinase/stress-activated protein kinase)pathway. ADMA also suppressed the activation of JNK triggered by death receptor ligand anti-Fas mAb and exogenous C₂-ceramide. Moreover, we demonstrated that ADMA pretreatment protected LoVo cells from doxorubicin hydrochloride-induced cell death and activation of the Fas/JNK pathway. In summary, our results suggest that the elevated ADMA in colon cancer patients may contribute to the blocking of apoptosis of cancer cells in response to stress and chemotherapy.

Decreased expression of microRNA-375 in nonsmall cell lung cancer and its clinical significance

OBJECTIVE

Emerging evidence has shown the association of aberrant microRNA-375 (miR-375) expression with tumourigenesis in many types of human malignancy. This prospective study characterized the contribution of miR-375 to the initiation and progression of nonsmall cell lung cancer (NSCLC).

METHODS

The real-time reverse transcription-polymerase chain reaction was used to examine miR-375 levels prospectively in 96 pairs of samples of NSCLC tissue and adjacent noncancerous tissue (> 2 cm from cancer tissue). The relationship between miR-375 levels and clinico pathological features was also explored.

RESULTS

MiR-375 was downregulated in 89% (85/96) of NSCLC samples compared with matched noncancerous tissue samples. Decreased miR-375 correlated significantly with advanced disease stage and lymphatic metastasis. Univariate and multivariate Cox proportional hazard regression analyses revealed that underexpression of miR-375 was an unfavourable prognostic factor for overall survival in NSCLC.

CONCLUSIONS

This study suggested that miR-375 is a novel prognostic indicator in NSCLC and might be a potential target for diagnosis and gene therapy.

RhoA modulates functional and physical interaction between ROCK1 and Erk1/2 in selenite-induced apoptosis of leukaemia cells

RhoA GTPase dysregulation is frequently reported in various tumours and haematologic malignancies. RhoA, regulating Rho-associated coiled-coil-forming kinase 1 (ROCK1), modulates multiple cell functions, including malignant transformation, metastasis and cell death. Therefore, RhoA/ROCK1 could be an ideal candidate target in cancer treatment. However, the roles of RhoA/ROCK1 axis in apoptosis of leukaemia cells remain elusive. In this study, we explored the effects of RhoA/ROCK1 cascade on selenite-induced apoptosis of leukaemia cells and the underlying mechanism. We found selenite deactivated RhoA/ROCK1 and decreased the association between RhoA and ROCK1 in leukaemia NB4 and Jurkat cells. The inhibited RhoA/ROCK1 signalling enhanced the phosphorylation of Erk1/2 in a Mek1/2-independent manner. Erk1/2 promoted apoptosis of leukaemia cells after it was activated. Intriguingly, it was shown that both RhoA and ROCK1 were present in the multimolecular complex containing Erk1/2. GST pull-down analysis showed ROCK1 had a direct interaction with GST-Erk2. In addition, selenite-induced apoptosis in an NB4 xenograft model was also found to be associated with the RhoA/ROCK1/Erk1/2 pathway. Our data demonstrate that the RhoA/ROCK1 signalling pathway has important roles in the determination of cell fates and the modulation of Erk1/2 activity at the Mek–Erk interplay level.

Differential regulation of locomotor activity to acute and chronic cocaine administration by acid-sensing ion channel 1a and 2 in adult mice

Acid-sensing ion channels (ASICs) are densely expressed in the brain with ASIC1a and ASIC2 channels being the predominant subtypes. These channels are enriched at synaptic sites and are central for the regulation of normal synaptic transmission. Moreover, increasing evidence links ASICs to the pathogenesis of various neurological and neuropsychiatric disorders. In this study, we explore the putative role of ASIC1a and ASIC2 in the regulation of behavioral sensitivity to the psychostimulant cocaine by utilizing ASIC1a or ASIC2 knockout mice. Acute cocaine injection induced a typical dose-dependent increase in locomotor activities in wild-type (WT) mice. However, in ASIC1a and ASIC2 mutant mice, different motor responses to cocaine were observed. In ASIC1a(-/-) mice, cocaine induced a significantly less motor response at all doses (5, 10, 20, and 30 mg/kg), while in ASIC2(-/-) mice, cocaine (5-20 mg/kg) stimulated locomotor activity to an extent comparable to WT mice. Only at 30 mg/kg, the cocaine-stimulated motor activity was reduced in ASIC2(-/-) mice. In a chronic cocaine administration model (20mg/kg, once daily for 5 days), a challenge injection of cocaine (10mg/kg, after 2-week withdrawal) caused an evident behavioral sensitization in the cocaine-pretreated WT mice. This behavioral sensitization to challenge cocaine was also displayed in ASIC1a(-/-) and ASIC2(-/-) mice. However, ASIC2(-/-) mice showed less sensitization to challenge cocaine when compared to WT and ASIC1a(-/-) mice. Our results demonstrate the important role of ASIC1a and ASIC2 channels in the modulation of behavioral sensitivity to cocaine. The two synapse-enriched ASIC subtypes are believed to play distinguishable roles in the regulation of behavioral responses to acute and chronic cocaine administration.

A Global Model for Closely Intermeshing Counter-rotating Twin Screw Extruders with Flood Feeding

A composite model has been developed to simulate the extrusion process for intermeshing counter-rotating twin-screw extruders. An experimentally based melting model, solids conveying model, and new improved metering model, were combined to develop this formulation. The procedure for global design of a flood feed intermeshing counter-rotating twin screw extruder is presented. Illustrative calculations are made for polyvinyl chloride and high density polyethylene in this type of machines with different screw designs. Computations are made for axial variation of the fill factor, pressure, temperature and melting profiles. Simulations were found to match with experimental results well. The model was also applied to scale-up.

Experimental Studies on Screw Characteristics in Closely Intermeshing Counter-rotating Twin Screw Extruder

Experimental studies were carried out to characterize the screw pumping behavior of various screw elements for a closely intermeshing counter-rotating twin screw extruder. The pumping capacity of the screw elements was compared to earlier flow simulations by some the authors of this type of twin screw extruder.

Structure Development in the Melt Spinning of Polypropylene/Ethylene Butene Copolymer Blends and Birefringence Suppression Effect

Polypropylene (PP)/ethylene butene copolymer (EBM) blends were melt-spun into fibers. The fiber orientation was determined by wide angle diffraction (WAXS) and birefringence. The birefringence of the blend fibers was much lower than that of the pure PP or EBM filaments spun at the same stresses. WAXS study showed that the PP phase had the same orientation versus stress relationship in its blends and in its pure state. However, EBM phase demonstrated much lower birefringence in its blends than in its pure state. The mechanism was explained as following. In melt spinning of the blends, the PP phase crystallized first. Before the PP phase crystallized, both PP and EBM phase had comparable modulus leading uniform stress distribution. After the PP phase crystallized, the modulus of PP phase became much larger than that of the EBM melt. Thus it would take most of the stress if it was the continuous phase leaving the EBM phase crystallizing at much lower stresses. This led to a large birefringence suppression of the EBM phase. In melt spinning of the blends with only 1 to 10 wt.% of PP, the dispersed PP phase could coalesce into a continuous surface layer. Thus small amount of PP could largely decrease the birefringence of EBM fibers.

The efficacy and safety of antiviral therapy with lamivudine to stop the vertical transmission of hepatitis B virus

The purpose of this study was to investigate the efficacy and safety of lamivudine (LAM) in stopping the vertical transmission of hepatitis B virus (HBV). Pregnant women with normal alanine transaminase (ALT) (n = 100) and with abnormal ALT (n = 100) who were positive for hepatitis B e antigen (HBeAg), and with HBV DNA (deoxyribonucleic acid) levels ≥1.0 × 107 copies/ml were enrolled in this study. One hundred volunteers (50 with normal ALT, 50 with abnormal ALT) received 100 mg of LAM daily from the 24th to 32nd week of gestation and the untreated 100 volunteers served as controls. All infants received passive-active immunoprophylaxis. Compared to the control group, the study group got a marked reduction in serum levels (P < 0.001) and high negativity (P < 0.001) of HBV DNA before delivery. They also got normalization in ALT levels as much as controls received general medication (P > 0.05). The prenatal transmission rate in the study group was significantly lower than that of the control group (P < 0.05). There were no differences in incidences of congenital malformation between the two groups (P > 0.05). LAM treatment can effectively and safely stop vertical transmission of HBV and normalize the ALT levels of pregnant women.

Human papillomavirus (HPV) infection and the risk of esophageal squamous cell carcinoma

There is currently no consensus on the relationship between human papillomavirus (HPV) infection and the pathogenic process of esophageal squamous cell carcinoma (ESCC). Therefore, a retrospective study was performed to explore the association between HPV infection and ESCC, where 225 patients with diagnosed ESCC and 224 matched controls were enrolled in the study and stratified according to smoking and alcohol consumption. Enzyme-linked immunosorbent assay was used to determine seropositivity to HPV by the detection of either IgG or IgM anti-HPV antibodies. In the non-smoking and non-alcohol-consuming subgroup, the incidence of ESCC of HPV seropositive subjects was similar with that of HPV seronegative subjects (P= 0.737, odds ratio [OR] 1.14, 95% confidence interval [CI] 0.54-2.40). However, in the smoking subgroup, there was a significant difference in the incidence of ESCC between HPV seropositive subjects and HPV seronegative subjects (P= 0.009, OR 2.22, 95% CI 1.22-4.04). In addition, there was a significantly higher association of the development of ESCC in HPV seropositive patients that smoke and drink than those that do not (P < 0.001, OR 10.31, 95% CI 4.04-26.29). Therefore, HPV infection is not an independent risk factor for developing ESCC in the non-smoking and non-alcohol-consuming group. For smokers, however, HPV infection increases the risk of the incidence of ESCC.