Measurements of All-Particle Energy Spectrum and Mean Logarithmic Mass of Cosmic Rays from 0.3 to 30 PeV with LHAASO-KM2A

We present the measurements of all-particle energy spectrum and mean logarithmic mass of cosmic rays in the energy range of 0.3-30 PeV using data collected from LHAASO-KM2A between September 2021 and December 2022, which is based on a nearly composition-independent energy reconstruction method, achieving unprecedented accuracy. Our analysis reveals the position of the knee at 3.67±0.05±0.15  PeV. Below the knee, the spectral index is found to be -2.7413±0.0004±0.0050, while above the knee, it is -3.128±0.005±0.027, with the sharpness of the transition measured with a statistical error of 2%. The mean logarithmic mass of cosmic rays is almost heavier than helium in the whole measured energy range. It decreases from 1.7 at 0.3 PeV to 1.3 at 3 PeV, representing a 24% decline following a power law with an index of -0.1200±0.0003±0.0341. This is equivalent to an increase in abundance of light components. Above the knee, the mean logarithmic mass exhibits a power law trend towards heavier components, which is reversal to the behavior observed in the all-particle energy spectrum. Additionally, the knee position and the change in power-law index are approximately the same. These findings suggest that the knee observed in the all-particle spectrum corresponds to the knee of the light component, rather than the medium-heavy components.

[Current status and development trend of vascular compressive therapy]

As a non-invasive and safe physical therapy modality, compressive therapy plays an indispensable role in the treatment of vascular diseases and wounds. However, the concept of compressive therapy has not been widely adopted at present. And there are also problems such as non-standard treatment methods and inconsistent standards of pressure devices. Therefore, it is urgent to improve the standard system of compressive therapy, improve the level of diagnosis and treatment of related diseases, and promote the further development of compressive therapy.

[Current status of registered drug and vaccine pediatric clinical trials in China]

Objective: To evaluate the current status of the registered pediatric drug or vaccine clinical trials in China for the purpose of providing a reference for the development of pediatric clinical trials in China. Methods: We collected the data about registered pediatric clinical trials that were conducted from September 6, 2013(Mandatory registration start date) to September 6, 2019 (Cut-off date) at Chinadrugtrials.org.cn platform. The survey items included trial name and number, drug classification, sponsor's information, current trial status, completion status, etc. The clinical trials were categorized by drug group (includes chemical medicine, traditional Chinese medicine and natural medicine, biological products) and by vaccine group. Results: During the six years 349 pediatric clinical trials were registered on the platform, including 162 pediatric drug trials and 187 vaccine trials. The numbers of chemical drugs and biological products registered in 2018 were 23 and 11, respectively, the highest in the history. The number of pediatric clinical trials of traditional Chinese medicine and natural medicine was 11 in 2014, but from 2015 to 2018 only 2 to 4 trials were registered each year. The overall completion rates of the registered drug and vaccine clinical trials were 22.8% (37/162) and 41.7%(78/187), respectively. Only 42 international multicenter pediatric clinical trial projects were registered on the platform. The numbers of drug and vaccine phase Ⅰ clinical trials were 4 and 46, respectively. Thirty-six pediatric endocrine system agent clinical trials were carried out, with the largest number of all the drug categories registered on the platform. Conclusions: In recent years the number of registered pediatric drug and vaccine clinical trials increased in China. However, the number is still very limited. It is urgent to further promote the development of pediatric clinical trials.

Biological Characteristics and Genetic Diversity of Phomopsis asparagi, Causal Agent of Asparagus Stem Blight

Asparagus stem blight is a regional disease. In the present study, we compared strains of Phomopsis asparagi from six different provinces to determine their biological characteristics and genetic diversity, differences in the pycnidium and conidium production, pathogenicity, and growth rate. Considerable differences were established in the pycnidium and conidium production among the P. asparagi strains from the six studied provinces. The largest pycnidium and conidium production had the strains from Fujian, followed by those from Hainan. The virulence of P. asparagi strains was significantly different but without a correlation with the geographical source of the strain. FJ2 had the highest virulence, followed by HN2, SD4, and SD5, whereas SD5 had the lowest virulence. The colony diameter and dry weight of the strains of asparagus stem blight fungus from the six provinces were substantially different. The colonies of HN1-5 had the largest diameters, whereas those of XT1-5, LT1-3, FJ1-5, and SX6 had smaller diameters. Four primers with good repeatability and strong specificity were selected from 100 intersimple sequence repeat (ISSR) primers. ISSR-PCR amplification was performed on 36 strains of asparagus stem blight fungus, and a large number of repeatable DNA fingerprints were obtained. Most of the amplified fragments were within 300 to 500 bp. In all, 69 total points, 64 multiple points, and 92.75% polymorphism points were established. The number of ISSR gene sites detected by four primers ranged from 14 to 20, with an average of 16 multiple sites. The copolymerization was divided into three groups: XT1-5, LT1-3, and FJ1-5, which were clustered into the first group; SD1-6, SX1-6, and HB1-6, clustered into the second group; and HN1-5 in the third group. The results of the cluster analysis revealed that the strains of the neighboring provinces had a nearer phylogenetic relationship than that between distant ones. Therefore, the system evolution of P. asparagi is related to the geographical distribution of its strains.

[The expression and role of PLUNC, TLR2 and NF-κB in nasal polyps]

Objective:To investigate the expression of palate, lung, nasal epithelium clone (PLUNC), Tolllike receptor 2 (TLR-2) and nuclear factor-Kappa B (NF-κB) in nasal polyps tissues and normal inferior turbinate mucosa. To analysethe correlation of their expression and to provide a new treatment of nasal polyps.Method:The specimens were divided into two groups: nasal polyps tissues group (n = 46) and normal inferior turbinate mucosa group (n = 19). EOS and others inflammatory cells was detected by HE staining. performing immunohistochemistry, we investigated the expression and distribution of PLUNC, TLR2 and NF-κB. Meanwhile we evaluated the positive expression and correlation of PLUNC, TLR2 and NF-κB between experimental group and control group. All data were processed by using SPSS 21.0 software.Result:EOS infiltration was significantly higher than the control group (P< 0.05). The expression level of PLUNC in experimental group is significantly lower, there is a statistical significance (P< 0. 05). The expression of TLR2 and NF-κB in experimental group is obviously higher than the control group, with statistical significance (P< 0.05). Spearman correlation analysia showed that PLUNC in experimental group is negatively correlated with TLR2 and NF-κB (r= －0.675, r= －0.550, P< 0.05). TLR2 is positively correlated with NF-κB (r= 0.540, P< 0.05). EOS infiltration degree positive correlation with TLR2 and NF-κB exist (r= 0.417, r= 0.470, P< 0.05), degree negative correlation with PLUNC exist (r= －0.859, P< 0.05).Conclusion:PLUNC expression in nasal polyps is lower than the normal inferior turbinate group. TLR2 and NF-κB expression in nasal polyps are higher than the normal inferior turbinate group.suggesting that the formation of nasal nolyps may be associated with lower natural immunity and the existing of infectious agents.

[A case report of myoepithelial carcinoma in the nasal septum]

Summary To explore the clinical features and treatment methods of myoepithelial carcinoma in the nasal septum.Myoepithelial carcinoma occurs in malignant epithelial tumors of the parotid region,from the nasal septum is more rare.The clinical feature of myoepithelial carcinoma in the nasal septum was atypical .The patients is mainly characterized by nasal obstruction,CT of tumor invasion nasal septum,on the right of the sinuses and lamina papyracea; pathology examination showed CK,S-100 protein and vimentin were positive,eventually,diagnosed with nasal septum myoepithelial carcinoma.

Danshen (Salvia miltiorrhiza) protects ovariectomized rats fed with high-saturated fat-sucrose diet from bone loss

Dietary patterns may interfere with the efficacy of herbal intervention. Our results demonstrated the protective effects of Salvia miltiorrhiza aqueous extract (SMA) on bone metabolism were influenced by levels of dietary fat and sucrose in ovariectomized (OVX) rats through its actions on attenuating lipid deposition and oxidative stress in rats.

INTRODUCTION

Salvia miltiorrhiza (SM), also known as Danshen, has been tested as an osteoporosis treatment in a series of small, short human trials that generally report improvements in bone property. However, dietary patterns may interfere with the effects of herbal intervention. We hypothesized that dietary fat and sucrose levels could influence the effects of SM supplementation on bone in estrogen-deficient animals.

METHODS

Six-month-old Sprague-Dawley sham or OVX rats were fed either a low-saturated fat-sucrose (LFS, a diet that was similar in composition to normal rat chow) or a high-fat-sucrose (HFS) diet and OVX rats were treated (8 rats/group) with SM aqueous extract (SMA, 600 mg/kg/day), 17β-estradiol (1 mg/kg/day), or vehicle for 12 weeks.

RESULTS

SMA significantly improved bone properties as revealed by the increase in trabecular bone mineral density and decrease in trabecular separation at proximal metaphysis of the tibia (PT) in HFS-fed OVX rats, but not in LFS-fed OVX rats. SMA greatly reduced lipid deposition and malondialdehyde levels, improved the activities of superoxide dismutase, catalase, and glutathione peroxidase in the livers of HFS-fed OVX rats. SMA could directly improve the proliferation and differentiation in vitro in an H₂O₂-induced preosteoblast cell model by attenuating cellular reactive oxygen species levels.

CONCLUSIONS

The protective effects of SMA on bone metabolism were influenced by dietary fat and sucrose levels in OVX rats. The ability of SMA to reduce bone loss in HFS-fed OVX rats was associated with the attenuation of lipid deposition and oxidative stress levels.

[The effect of liraglutide in combination with human umbilical cord mesenchymal stem cells treatment on glucose metabolism and β cell function in type 2 diabetes mellitus]

OBJECTIVE

To observe the effect of liraglutide (LIRA) in combination of umbilical cord mesenchymal stem cells (hUC-MSCs) in treating type 2 diabetes mellitus.

METHODS

Eligibility criteria for subjects includes: type 2 diabetes mellitus with more than 10 years duration; having been treated with secretagogues, metformin and insulin in combination with LIRA for at least 6 months; poor glycemic control [glycosylated hemoglobin A1c(HbA1c) 7%-10%]. Totally, twelve patients were enrolled and randomly divided into two groups: the group A (LIRA group, n=6) and the group B (LIRA+ hUC-MSCs group, n=6). The hUC-MSCs were transplanted through infusing of 1×10(6) cells /kg via pancreatic artery directed by interventional radiology on the first day, and followed by infusing 1×10(6) cells /kg through peripheral vein on the eighth, the fifteenth and the twenty-second day sequentially. The control subjects were infused with saline. Both groups were treated with LIRA for 24 weeks at the same period. Fasting plasma glucose(FPG), 2h postprandial plasma glucose(2hPG) and HbA1c were measured. A 75 g oral glucose tolerance test(OGTT)was performed. The early phase of C peptide(CP) secretion function(ΔCP30/ΔG30), the total amount of C peptide secretion function(AUCCP180)and Homeostasis model assessment of insulin resistance (HOMA-IR) were calculated.

RESULTS

(1) The baseline FPG, 2hPG, HbA1c, ΔCP30/ΔG30, AUCCP180 and HOMA-IR were comparable between the two groups(P>0.05). (2) Compared with subjects in group A, FPG, 2hPG and HbA1c levels were significantly decreased in subjects in group B [(8.33±0.99) mmol/L vs (6.64±0.79)mmol/L, (13.85±0.86) mmol/L vs (8.65±1.12) mmol/L, (7.82±0.31)% vs (6.82±0.53)%, P<0.05]. (3) Compared with group A, ΔCP30/ΔG30 and AUCCP180 were significantly increased, and HOMA-IR was significantly decreased in group B(0.22±0.13 vs 0.70±0.38, 12.52±5.30 vs 21.16±3.17, 9.46±4.88 vs 4.30±2.68, P<0.05).

CONCLUSION

LIRA treatment in combination with hUC-MSCs improves glucose metabolism and the β cell function in type 2 diabetic patients. (ClinicalTrials.gov NCT01954147).

Association between IL18-607C/A and -137G/C polymorphisms and susceptibility to non-small cell lung cancer in a Chinese population

Lung cancer is one of the main causes of cancer-related mortality in males and females worldwide. A pleiotropic effect has been observed in the interleukin 18 gene (IL18); its effects include the activation of natural killer cell cytotoxicity and the promotion of the Th1 immune response through the alteration of the expression of interferon-γ and TNF-α in humans. IL18 is therefore involved in the elimination of tumor cells in the human body. We recruited 357 patients with non-small cell lung cancer (NSCLC) and 414 controls to evaluate the correlation between two genetic variations (IL18-607C/A and IL18-137G/C) and the pathogenesis of NSCLC. We used polymerase chain reaction-restriction fragment length polymorphism to genotype IL18-607C/A and IL18-137G/C. Statistical analysis revealed that individuals harboring the AA genotype of IL18-607C/A had an increased risk of NSCLC compared to those harboring the CC genotype (OR = 2.20, 95%CI = 1.30-3.74). Individuals expressing the A allele of IL18-607C/A had an elevated risk of developing NSCLC compared to those expressing the C allele (OR = 1.31, 95%CI = 1.06-1.62). In summary, our analysis shows that the IL18-607C/A genetic variation is related to the risk of NSCLC, whereas the IL18-137G/C variation is not. Therefore, the IL18-607C/A variation is related to the pathogenesis of NSCLC in the Chinese population studied.

[Research advances in drug-induced autoimmune hepatitis]

Drug induced autoimmune hepatitis (DIAIH) refers to the liver injury mediated by drug-induced autoimmune reaction. Since it has similar clinical features as idiopathic autoimmune hepatitis, it is often difficult to make differential diagnosis in clinical practice. A deep understanding of the development, pathogenesis, related drugs, risk factors, and clinical and histological features of DIAIH helps with the correct diagnosis and treatment of DIAIH.

[Preliminary application of amide proton transfer imaging signal in acute ischemic stroke]

OBJECTIVE

To apply amide proton transfer magnetic resonance imaging (APT-MRI) technique to acute ischemic stroke, and to discuss clinical values of the APT-MRI main parameter - MTRasym(3.5 ppm).

METHODS

A total of 18 emergency admitted patients, with acute ischemic stroke from Beijing Hospital, were recruited from March to November 2015. Eventually, 18 patients (male 14, female 4, average age 72 years old, age ranged from 52 to 92 years, symptom onset ≤24 hours, 2 patients≤ 6 hours) were included in this study. All patients underwent MR scanning on the brain at 3.0 Tesla. Besides the conventional scans for stroke, the APT sequence (saturation time 0.8 s, saturation power 2 μT) was performed. APT weighted (APTW) images were calculated using magnetization transfer ratio asymmetry at 3.5 ppm with respect to water. MRI signals in APTW, diffusion weighted images (DWI) and fluid attenuated iversion recovery (FLAIR) were visually evaluated. Shapiro-Wilk tests were performed to find out the distribution of MTRasym(3.5 ppm) in the whole sample, infarction regions, and normal appearing white matter (NAWMs), respectively. Detrended normal P-P plots were also used to evaluate its normality. Paired-t test and two-sample t test were applied to compare the mean MTRasym(3.5 ppm) of infarction regions with that of contra lateral NAWMs.

RESULTS

(1) High signal intensity was observed in DWI and FLAIR in all 18 patients. However, signal intensity was somewhat different in APTW. 13 patients were found decreased APT effect, and 5 patients were with equal APT effect in infarction regions. In NAWMs, 14 patients were found equal APT effect, and 4 patients were with decreased APT effect. (2) MTRasym(3.5 ppm)s were proven, with Shapiro-Wilk test, to distribute normally within the whole sample (W=0.964, P=0.288), infarction regions (W=0.962, P=0.645), and NAWMs(W=0.929, P=0.187). However, its normality was not so satisfactory due to greater deviations (absolute value>0.06) of some cases in detrended normal P-P plots. (3) Paired-t test analysis showed that MTRasym(3.5 ppm) in infarction regions (-0.035%±1.020%) was significantly lower than that in NAWMs (0.386%±0.790%) (t=-2.273, P=0.036). However, there was no statistically significant difference between infarction regions and NAWMs when two sample t-test was performed (t=-1.386, P=0.175).

CONCLUSION

MTRasym(3.5 ppm) can be used to evaluate acute ischemic stroke with a broad future scope in clinical.

Sensitive determinations of Cu, Pb, Cd, and Cr elements in aqueous solutions using chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy

In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R² of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 μg/mL for the unitary solution, and in the range of 0.025-0.420 μg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.

Application of retrograde dissection method for isolation of bone marrow cells from rat femurs and tibiae

Currently, there is no practical and efficient method for the isolation of bone marrow cells (BMCs) from rat femurs and tibiae. Here, we attempted to develop a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae. Rat femurs and tibiae were dissected from the ankle to the hip joint; subsequently, a three-step "locate-slide-twist" procedure was performed using scissors and forceps to remove the femurs and tibiae completely, from the surrounding musculature. The bones were flushed with phosphate-buffered saline to harvest BMCs. The femurs and tibiae were dissected in 1.8 ± 0.6 min, and the BMC suspension preparation time was 13.1 ± 2.3 min. The bone marrow cavities did not incur any fractures or injuries during the isolation. Culture of harvested BMCs for 72 h led to a significant increase in cell number from 4.4 ± 0.3 x 106 to 6.9 ± 0.7 x 10(6) (P < 0.01) with no significant decrease in viability (98.1 ± 0.6% vs 96.2 ± 1.1%; P > 0.05). Microscopic examination of the isolated BMCs after the 72-h incubation period revealed the no-microbial or muscle cell contamination. Furthermore, flow cytometry revealed that cultured BMCs (72-h culture) grew well. Here, we have reported a rapid, simple, effective, and non-contaminating method for the isolation of BMCs from rat femurs and tibiae by using retrograde dissection. This method can be used to harvest a large number of viable BMCs without the risk of contamination from muscle and connective tissues.

Polymorphism identification in BMP15 and GDF9 genes and their association with egg production in chickens

1. Mutations in growth differentiation factor 9 (GDF9) and bone morphogenetic protein 15 (BMP15) are significantly associated with reproductive performance in mammals and the objective of the present study was to identify polymorphic sites and elucidate the association between genotypes in BMP15 and GDF9 and egg production. 2. Polymorphisms in BMP15 exon1 and GDF9 exon2 were detected by DNA sequencing and PCR-RFLP. Three SNPs were detected in each of BMP15 (A111G, C231T and C34T) and GDF9 (G593A, T824C and C896T). C34T leads to the substitution of Leu by Phe, which was predicted to affect protein function. 3. Results of the association analysis indicated that C34T had an effect on total egg production at 300 d of age (EN) and age at first laying (AFE). G593A affected EN and both C231T and C896T influenced AFE. The TGC1TGC1 diplotype in BMP15 had the highest EN. 4. In conclusion, EN may be significantly improved by marker-assisted selection of the BMP15 genotypes in maternal lines of Shaobo hens.

Acidity measurement of iron ore powders using laser-induced breakdown spectroscopy with partial least squares regression

Laser-induced breakdown spectroscopy (LIBS) with partial least squares regression (PLSR) has been applied to measuring the acidity of iron ore, which can be defined by the concentrations of oxides: CaO, MgO, Al₂O₃, and SiO₂. With the conventional internal standard calibration, it is difficult to establish the calibration curves of CaO, MgO, Al₂O₃, and SiO₂ in iron ore due to the serious matrix effects. PLSR is effective to address this problem due to its excellent performance in compensating the matrix effects. In this work, fifty samples were used to construct the PLSR calibration models for the above-mentioned oxides. These calibration models were validated by the 10-fold cross-validation method with the minimum root-mean-square errors (RMSE). Another ten samples were used as a test set. The acidities were calculated according to the estimated concentrations of CaO, MgO, Al₂O₃, and SiO₂ using the PLSR models. The average relative error (ARE) and RMSE of the acidity achieved 3.65% and 0.0048, respectively, for the test samples.

Genetic polymorphisms of the BMAP-28 and MASP-2 genes and their correlation with the somatic cell score in Chinese Holstein cattle

DNA sequencing, nested polymerase chain reaction (PCR), and PCR-restriction fragment length polymorphism were used to investigate mutations in the coding regions of the bovine myeloid antimicrobial peptide-28 (BMAP-28) and mannan-binding lectin-associated serine protease-2 (MASP-2) genes in 249 Chinese Holstein dairy cows. The associations between the polymorphisms and somatic cell score (SCS) were analyzed to determine the potential of these genes as genetic markers for breeding mastitis-resistant dairy cattle. The results revealed a C-86G synonymous mutation in the BMAP-28 gene that caused no alteration in the amino acid sequence. G553A mutation was found in the MASP-2 gene that led to the substitution of glycine with serine. The chi-square test showed that the G553A mutation was in Hardy-Weinberg equilibrium in the Chinese Holstein dairy cows, whereas the C-86G mutation was not. The variance analysis of the influence of group loci and different genotypes on the SCS showed that the SCS of genotype CC was significantly lower than those of genotypes CG and GG (P < 0.05) of the C-86G mutation, and that the SCS of genotype GG was significantly lower than those of genotypes GA and AA (P < 0.05) of the G553A mutation. Genotype combination analysis showed that the combination of the BMAP-28 genotype CC and the MASP-2 genotype GG was the best one, in which the SCS was significantly lower than those in the other combinations. Thus, this combination might be useful as a molecular and genetic marker of mastitis in Chinese Holstein dairy cows.

CCL17 Induces Trophoblast Migration and Invasion by Regulating Matrix Metalloproteinase and Integrin Expression in Human First-Trimester Placenta

Chemokines and chemokine receptors have been implicated a pivotal role in trophoblast differentiation and in the formation of a functionally normal placenta. In this study, we present data that highlight the involvement of chemokine ligand 17/chemokine receptor 4 (CCL17/CCR4) expression at the fetomaternal interface and expand its biological relevance of influence during trophoblast differentiation and placentation. By immunohistochemistry, we found that CCL17 was abundantly expressed in the decidua and trophoblasts, especially in cell columns. The receptor for CCL17, CCR4, was specifically expressed in invading interstitial extravillous trophoblasts. Furthermore, by transwell migration, invasion assays, and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, we found that exogenous CCL17 concentrations paralleled the invasive potential of cytotrophoblasts to some extent, with no significant effect on cell proliferation. Using Western blotting, we demonstrated that the stimulatory effect of CCL17 was related to the expression of matrix metalloproteinase 2 (MMP-2), MMP-13, integrin α5, and integrin β1, although it downregulated tissue inhibitors of MMP-1 expression. In conclusion, our findings suggest that CCL17, as a differentiation-related molecule coexpressed by decidua and trophoblast, stimulates extravillous trophoblast migration and directs invasion mainly via modulating integrins, MMPs, and its inhibitor levels.

Abstract P6-07-02: Pharmacoeconomic evaluation of denosumab for the treatment of bone metastases in patients with advanced breast cancer in Canada

Background: Skeletal-related events (SREs) occur in 80% of patients with advanced breast cancer (BC) and bone metastases. SREs are costly and can be painful and debilitating, impacting patients’ quality of life and morbidity. While intravenous bisphosphonates such as pamidronate (PAM) and zoledronic acid (ZA) have demonstrated clinical benefit in reducing SREs, skeletal metastases remain a problem as treatments that are more efficacious, well tolerated, more convenient and less costly to administer are needed. Denosumab (XGEVA™) is a novel subcutaneous human monoclonal antibody therapy that significantly reduces the risk of developing SREs in patients with bone metastases from BC.

Objective: The objective of this project is to estimate the incremental cost-effectiveness of denosumab relative to ZA and PAM in the treatment of advanced BC patients with bone metastases.

Methods: A lifetime Markov model with four-week cycle lengths was developed with three health states: on treatment; off treatment; and death. The model included the risk of an SRE for patients on and off treatment and adverse events during treatment. Efficacy was measured as reduction in SREs. Head-to-head efficacy data, transition probabilities, and risk of adverse events were obtained from the clinical trial of denosumab versus ZA. (Stopeck AT et al JCO 2010) Efficacy data compared to PAM was determined from a published network meta-analysis. (Ford JA et al Eur J Cancer 2012) The baseline SRE risk was derived from clinical trial data due to the absence of real-world Canadian data. Analyses were conducted from the Canadian healthcare system perspective and reported in 2011 $CAD. Resource use was determined from a Canadian retrospective chart review of oncology patients with SREs. Costs were based on the published literature, the Ontario Case Costing Initiative, and input from a physician panel. Utility inputs were based on a time trade-off study. (Matza LS et al. Eur J Health Econ 2013) Bisphosphonate administration costs were derived from a published time and motion study. (Dranitsaris G et al. J Oncol Pharm Pract 2001) Outcomes were measured as both SREs avoided and quality-adjusted life years (QALYs) gained. Dominance was assessed or incremental cost-effectiveness ratios calculated per SRE avoided and per QALY gained, for denosumab compared to ZA and PAM. Future costs and QALYs were discounted at 5% per annum. Sensitivity analyses were conducted to test the robustness of the results.

Results: Denosumab was dominant and resulted in $5,733 in cost savings compared to ZA and $2,566 in cost savings compared to PAM based on a probabilistic analysis. Cost savings was driven by differences in drug administration costs and reduction in SREs. SREs avoided were 0.27 and 0.57 compared to ZA and PAM respectively. Denosumab resulted in 0.012 QALYs gained and 0.025 QALYs gained per patient compared to ZA and PAM, respectively. Sensitivity analyses showed the results were robust but most sensitive to drug administration costs and the relative risk of SREs.

Conclusion: Compared to both ZA and PAM, denosumab is more efficacious and offers better value for money (i.e. dominant) in Canada for managing SREs in patients with advanced BC and bone metastases.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-07-02.

Relationships between biochemical and physiological changes induced by exercise in postmyocardial infarction patients

AIM

AIM of the study was to examine the relationships between biochemical and physiological changes induced by exercise in postmyocardial infarction patients (PMIP) during the early stages of cardiac rehabilitation.

METHODS

Forty-nine male non-blockade recent PMIP, aged 63.8 ± 4.7 years, performed a graded exercise test on a motorised treadmill until volitional cessation or reaching any of the American College of Sports Medicine criteria. Blood pressure and rate-pressure product (RPP) were recorded every three minutes. A 12-lead electrocardiogram was monitored continuously and heart rate (HR) was taken from this. Blood samples were obtained by two methods; those used for testing blood lactate (BL) were taken from an already warmed finger tip before and during exercise, and the others used for enzymatic analysis based on lactate dehydrogenase (LDH), lactate dehydrogenase isoenzyme 1 (LDH-1), creatine kinase (CK) and creatine kinase polypeptide sub-unit MB (CK-MB) were collected by venipuncture from the antecubital vein pre and immediate post exercise test.

RESULTS

Highly significant correlations existed between exercise-induced changes in HR, RPP, BL and ST segment level with increased enzymes activity in serum, and 73.1% to 90.1% of the variance in percentage increase of the enzyme activity could be predicted from the variance in percentage increase of HR during exercise. However, the mechanism of these relationships may differ.

CONCLUSION

Since the rise in serum enzymes during submaximal exercise is primarily attributed to changes in membrane permeability in fatigued muscle, these relationships provide useful guidance to health professionals obtaining biochemical information about muscle fatigue.

Preventive effect of tert-butylhydroquinone on scrotal heat-induced damage in mouse testes

To investigate the effect of tert-butylhydroquinone (tBHQ) on scrotal heat-induced damage in mice testes, 8-week-old mice were divided into 6 groups and administered with or without tBHQ through diet (10 mg/g), intraperitoneal injection (100 mg/kg body weight), or intratestis injection (12.5 mg/kg body weight), respectively. After single scrotal heat exposure (42 °C for 25 min), trunk blood and testes were collected 48 h later. The testes from diet and intraperitoneal tBHQ-treated mice showed more compact interstitial cells and less germ cell loss in the seminiferous epithelium compared with their corresponding non-tBHQ groups. However, intratestis tBHQ treatment showed no marked difference relative to the non-treatment group. In addition, pre-treatment of tBHQ caused lower testosterone concentrations and reduced expression of cytochrome P450 17α-hydroxylase/17,20-lyase (CYP 17) compared to the corresponding non-tBHQ groups. The results indicated that scrotal heat-induced structural damage was partly prevented by pre-treatment of tBHQ, which could be used as an effective antioxidant for preventing scrotal heat-mediated male infertility.

The chemokine CXCL6 restricts human trophoblast cell migration and invasion by suppressing MMP-2 activity in the first trimester

STUDY QUESTION

Can the chemokine CXCL6 affect trophoblast cell migration and invasion in human first-trimester placenta?

SUMMARY ANSWER

Chemokine CXCL6 inhibits trophoblast cell migration and invasion by suppressing matrix metalloproteinase (MMP)-2 activity in human first-trimester placenta.

WHAT IS KNOWN ALREADY

Several chemokines including CXCL8, CXCL12, CXCL14, CXCL16, CX3CL1, CCL14 and CCL4 can promote or inhibit trophoblast cell migration and invasion in human first-trimester placenta.

STUDY DESIGN, SIZE, DURATION

We used the trophoblast cell line HTR8/SVneo cells, primary trophoblast cells and villi explants to investigate the effect of rhCXCL6 on trophoblast cell migration and invasion.

PARTICIPANTS/MATERIALS, SETTING, METHODS

First, the CXCL6 RNA transcript level was detected in HTR8/SVneo cells derived from human first-trimester, second-trimester and third-trimester placenta by RT-PCR. Protein expression of CXCL6 and its receptors was tested in first-trimester placenta by immunohistochemistry. Secreted CXCL6 protein was detected in HTR8/SVneo cell supernatants by enzyme-linked immunosorbent assay. Secondly, the effect of rhCXCL6 on HTR8/SVneo cell proliferation was assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Thirdly, the effect of rhCXCL6 on cell migration and invasion of HTR8/SVneo cells, primary trophoblast cells and villi explants was tested by transwell migration and invasion assays, respectively. Last, MMP-2 and MMP-9 activity in the supernatants of HTR8/SVneo and primary trophoblast cells treated by rhCXCL6 in the invasion assay was assessed by gelatin zymography.

MAIN RESULTS AND THE ROLE OF CHANCE

Abundance of the CXCL6 RNA transcript increased with pregnancy development. CXCL6 and its receptor were expressed in several cells at the human maternal-fetal interface. RhCXCL6 inhibited trophoblast cell migration and invasion by suppressing MMP-2 activity.

LIMITATIONS, REASONS FOR CAUTION

These experiments are only in vitro.

WIDER IMPLICATIONS OF THE FINDINGS

According to the literature, CXCL6 could promote tumour cell migration and invasion by accelerating MMP-9 activity. However, CXCL6 inhibited trophoblast cell migration and invasion by suppressing MMP-2 activity in human first-trimester interface. These data suggest that strict regulation of CXCL6 is required for normal migration and invasion of cells, such as those involved at the maternal-fetal interface.

Reliability and validity of the overactive bladder symptom score in Hong Kong Chinese

OBJECTIVE

To validate the Hong Kong Chinese translation of the Overactive Bladder Symptom Score questionnaire (OABSS-HKC).

DESIGN

Cross-sectional study.

SETTING

Five urology clinics of different regional hospitals in Hong Kong.

PARTICIPANTS

The Overactive Bladder Symptom Score questionnaire was translated and culturally adapted for Hong Kong Chinese, according to the Principles of Good Practice for the Translation and Cultural Adaptation Process for Patient-Reported Outcomes Measures. Chinese-speaking patients with overactive bladder symptoms were recruited from five urology clinics. The patients completed the OABSS-HKC, a 3-day micturition diary, International Prostate Symptom Scores, and the Patient Perception of Bladder Condition questionnaires (visit 1), and again after a 2-week interval (visit 2). Test-retest reliability was evaluated by the intraclass correlation coefficient and weighted Kappa coefficient. The relationship between OABSS-HKC total scores and items in the comparison measures was evaluated using Spearman's correlation coefficients.

RESULTS

The OABSS-HKC was successfully translated and culturally adapted. Fifty-one patients completed the validation study. A high level of reliability was observed between the OABSS-HKC total score answered at visit 1 and 2 for all subjects (intraclass correlation coefficient, 0.82) and among the four items answered (weighted Kappa coefficients, 0.57-0.75). The OABSS-HKC total score correlated significantly with numbers of micturitions, incontinence and urgency episodes recorded in the 3-day micturition diary, as well as the total International Prostate Symptom Scores and the Patient Perception of Bladder Condition score. However, the OABSS-HKC total score was not significantly associated with nocturia episodes, total voided volume, or number of pads used.

CONCLUSIONS

The OABSS-HKC total scores are reliable and moderately valid for the quantitative evaluation of overactive bladder symptoms in Hong Kong Chinese-speaking adults.

D2 lymphadenectomy can disseminate tumor cells into peritoneal cavity in patients with advanced gastric cancer

We sought to determine the dissemination of gastric cancer cells before and after radical D2 surgery and to determine the effectiveness of EIPL in preventing post-operative peritoneal metastasis. 64 patients were recruited with advanced gastric cancer for our final analysis. Complete curative gastrectomy with D2 lymphadenectomy was performed on the 64 patients. Before surgery, peritoneal lavage fluid was collected for cytological analysis by cell smearing and immunohistochemistry to detect disseminated cancer cells (S1). Following tumor and lymph node resection, peritoneal lavage fluid was collected for cytological examination (S2). The patients were treated by extensive intra-operative peritoneal lavage (EIPL) with normal saline (n = 31) or distilled water (n = 33). The peritoneal lavage fluid was collected for cytological examination (S3). At S1 stage, 18 patients (28.1%) were positive for disseminated cancer cells in their abdominal fluid. After D2 lymphadenectomy, 34 patients (53.1%) had disseminated cancer cells in their abdominal fluid at stage S2, which indicated that the D2 lymphadenectomy caused in an additional 16 (16/46, 34.8%) patients positive for disseminated cancer cells. After EIPL with either normal saline or distilled water at the S3 stage), all the patients were negative for disseminated cancer cells in their abdominal fluid. A total of six patients died, and four patients had recurrencent cancer. These findings indicate that D2 lymphadenectomy can disseminate gastric cancer cells, and post-operative lavage of the abdominal cavity can eliminate cancer cell dissemination and decrease the risk of peritoneal metastasis.

SLICC/ACR damage index independently associated with left ventricular diastolic dysfunction in patients with systemic lupus erythematosus

Left ventricular (LV) diastolic dysfunction has been reported in both active and inactive systemic lupus erythematosus (SLE) patients without clinical evidence of cardiovascular disease. However, the relationship between the long-term inflammatory burden reflected by the SLICC/ACR damage index and LV diastolic function has not been studied. Eighty-two SLE patients and 82 controls matched for age, sex, body mass index, blood pressure and heart rate underwent echocardiography with tissue Doppler imaging (TDI). LV diastolic function was estimated by the myocardial early diastolic velocity (E') at the lateral annulus. There were 51 patients (62.2%) with nephritis, 23 patients (28.0%) with hypertension, 21 patients (25.6%) with vasculitis, 16 patients (19.5%) with pulmonary hypertension, 4 patients (4.9%) with cerebrovascular disease and 2 patients (2.4%) with diabetes mellitus. Sixty-two patients (75.6%) were taking prednisone and 35 patients (42.7%) used a immunosuppressant. Forty-five patients (54.8%) had active disease and suffered from disease-related end-organ damage. Patients with SLICC/ACR damage index ≥1 had more evidence of LV diastolic dysfunction with lower lateral annulus E' (9.6 ± 3.4 vs 12.9 ± 3.5 cm/s, p < 0.001) than those without. In addition, the proportion of patients with abnormal LV myocardial relaxation (defined as lateral E' < 10.0 cm/s) (51.1% vs 16.2%, χ(2) = 10.8, p = 0.001) were significantly higher. Multivariate analysis showed that the SLICC/ACR damage index ≥1 was independently associated with LV diastolic dysfunction (OR = 3.80, 95%CI: 1.21-11.95, p = 0.023) after adjusting for hypertension, disease duration and medical therapy. This may suggest that the overall inflammatory burden in SLE, as reflected by SLICC/ACR damage index, is associated with the development of diastolic dysfunction in SLE patients.

Optimally enhanced optical emission in laser-induced breakdown spectroscopy by combining spatial confinement and dual-pulse irradiation

In laser-induced breakdown spectroscopy (LIBS), a pair of aluminum-plate walls were used to spatially confine the plasmas produced in air by a first laser pulse (KrF excimer laser) from chromium (Cr) targets with a second laser pulse (Nd:YAG laser at 532 nm, 360 mJ/pulse) introduced parallel to the sample surface to re-excite the plasmas. Optical emission enhancement was achieved by combing the spatial confinement and dual-pulse LIBS (DP-LIBS), and then optimized by adjusting the distance between the two walls and the interpulse delay time between both laser pulses. A significant enhancement factor of 168.6 for the emission intensity of the Cr lines was obtained at an excimer laser fluence of 5.6 J/cm(2) using the combined spatial confinement and DP-LIBS, as compared with an enhancement factor of 106.1 was obtained with DP-LIBS only. The enhancement mechanisms based on shock wave theory and reheating in DP-LIBS are discussed.

Quantum dot-based nanocomposites for biomedical applications

Quantum dot (QD) has been extensively investigated as a nanoprobe to replace conventional organic dyes due to its unique optical properties. However, nanotoxicity of QD greatly hampers its biomedical applications, particularly in in vivo imaging. It is critical to functionalize QD and/or composite QD with other functional materials for biocompatibility, multifunction and expanded applications. In this review, advances of QD-based nanocomposites are addressed with emphasis of their synthesis, fundamental understanding and applications in biosensor, multimodal imaging, drug delivery, diagnostics and cancer therapy. Some specific QD-based bionanosystems and future development directions are also discussed.

Selective Upregulation of Brain-Derived Neurotrophic Factor (BDNF) Transcripts and BDNF Direct Induction of Activity Independent N-Methyl-D-Aspartate Currents in Temporal Lobe Epilepsy Patients with Hippocampal Sclerosis

Brain-derived neurotrophic factor (BDNF) plays a critical role in many aspects of neuronal biology and hippocampal physiology and pathology, and has been implicated as a potential therapeutic target in temporal lobe epilepsy (TLE). BDNF total mRNA and its six transcripts were compared in the hippocampal tissue of TLE patients with or without hippocampal sclerosis (HS) by real-time fluorescence quantitative polymerase chain reaction. Excitatory actions induced by BDNF on hippocampal cells were investigated by whole-cell patch-clamp recordings. Statistically significant increases in three human BDNF mRNA transcripts were observed in TLE patients with HS compared with those without HS (transcripts 2, 3 and 5 exhibited 2.1-, 2.3-and 4.1-fold increases, respectively); there were no significant increases in other transcripts. BDNF directly induced N-methyl-d-aspartate currents in dentate granule cells of TLE patients with HS. These results demonstrated that BDNF transcripts were selectively upregulated in TLE patients with HS compared with those without HS. Moreover, BDNF induced excitability of dentate granule cells in TLE patients with HS.

Enhancement of optical emission from laser-induced plasmas by combined spatial and magnetic confinement

To enhance optical emission in laser-induced breakdown spectroscopy, both a pair of permanent magnets and an aluminum hemispherical cavity (diameter: 11.1 mm) were used simultaneously to magnetically and spatially confine plasmas produced by a KrF excimer laser in air from pure metal and alloyed samples. High enhancement factors of about 22 and 24 in the emission intensity of Co and Cr lines were acquired at a laser fluence of 6.2 J/cm2 using the combined confinement, while enhancement factors of only about 11 and 12 were obtained just with a cavity. The mechanism of enhanced optical emission by combined confinement, including shock wave in the presence of a magnetic field, is discussed. The Si plasmas, however, were not influenced by the presence of magnets as Si is hard to ablate and ionize and hence has less free electrons and positive ions. Images of the laser-induced Cr and Si plasmas show the difference between pure metallic and semiconductor materials in the presence of both a cavity and magnets.

Generation of high-temperature and low-density plasmas for improved spectral resolutions in laser-induced breakdown spectroscopy

Improved spectral resolutions were achieved in laser-induced breakdown spectroscopy (LIBS) through generation of high-temperature and low-density plasmas. A first pulse from a KrF excimer laser was used to produce particles by perpendicularly irradiating targets in air. A second pulse from a 532 nm Nd:YAG laser was introduced parallel to the sample surface to reablate the particles. Optical scattering from the first-pulse plasmas was imaged to elucidate particle formation in the plasmas. Narrower line widths (full width at half maximums: FWHMs) and weaker self-absorption were observed from time-integrated LIBS spectra. Estimation of plasma temperatures and densities indicates that high temperature and low density can be achieved simultaneously in plasmas to improve LIBS resolutions.

Measurement of w-InN/h-BN Heterojunction Band Offsets by X-Ray Photoemission Spectroscopy

X-ray photoelectron spectroscopy has been used to measure the valence band offset (VBO) of the w-InN/h-BN heterojunction. We find that it is a type-II heterojunction with the VBO being -0.30 ± 0.09 eV and the corresponding conduction band offset (CBO) being 4.99 ± 0.09 eV. The accurate determination of VBO and CBO is important for designing the w-InN/h-BN-based electronic devices.

Multifunctional CuO nanowire devices: p-type field effect transistors and CO gas sensors

We report the properties of a field effect transistor (FET) and a gas sensor based on CuO nanowires. CuO nanowire FETs exhibit p-type behavior. Large-scale p-type CuO nanowire thin-film transistors (10(4) devices in a 25 mm(2) area) are fabricated and we effectively demonstrate their enhanced performance. Furthermore, CuO nanowire exhibits high and fast response to CO gas at 200 degrees C, which makes it a promising candidate for a poisonous gas sensing nanodevice.

Evolution of the clock from yeast to man by period-doubling folds in the cellular oscillator

Analysis of genome-wide oscillations in transcription reveals that the cell is an oscillator and an attractor and that the maintenance of a stable phenotype requires that maximums in expression in clusters of transcripts must be poised at antipodal phases around the steady state-this is the dynamic architecture of phenotype. Plots of the path through concentration phase space taken by all of the transcripts of Saccharomyces cerevisiae yield a simple three-dimensional surface. How this surface might change as period lengthens or as a cell differentiates is at the center of current work. We have shown that changes in gene expression in response to mutation or perturbation by drugs occur through a folding or unfolding of the surface described by this circle of transcripts and we suggest that the path from this 40-minute oscillation to the cell cycle and circadian rhythms takes place through a series of period-two or period-three bifurcations. These foldings in the surface of the putative attractor result in an increasingly dense set of nested trajectories in the concentrations of message and protein. Evolutionary advantage might accrue to an organism that could change period by changes in just one or a few genes as day length increased from 4 hours in the prebiotic Earth, through 8 hours during the expansion of photoautotrophs, to the present 24 hours.

Improving interval estimation of binomial proportions

In this paper, we propose one new confidence interval for the binomial proportion; our interval is based on the Edgeworth expansion of a logit transformation of the sample proportion. We provide theoretical justification for the proposed interval and also compare the finite-sample performance of the proposed interval with the three best existing intervals-the Wilson interval, the Agresti-Coull interval and the Jeffreys interval-in terms of their coverage probabilities and expected lengths. We illustrate the proposed method in two real clinical studies.

Effect of inhaled formaldehyde on learning and memory of mice

In this study, we investigated the effect of inhaled formaldehyde on learning and memory capacity. After exposure to 0 (control), 1 and 3 mg/m(3) of gaseous formaldehyde respectively, the behavior of mice in a Morris water maze, the expression of NR1, NR2B mRNA and oxidative damage levels in mice brain were analyzed. The water maze performance, the activities of dismutase superoxide (SOD) and levels of glutathione (GSH) decreased significantly in 3 mg/m(3) group (P < 0.01, compared with control group); while malondialdehyde (MDA) contents and expression of NR1 and NR2B genes increased significantly after exposure to 3 mg/m(3) of gaseous formaldehyde (P < 0.05, <0.01, <0.01, compared with control group). These findings indicate that inhaled formaldehyde negatively affects learning and memory at 3 mg/m(3) of gaseous formaldehyde but not at lower levels. Oxidative stress-induced neuron damages in the brain may be the possible mechanism for these effects.

PRACTICAL IMPLICATIONS

This study indicates that inhaled formaldehyde starts to negatively affect learning and memory at a middle concentration of formaldehyde without interference of other indoor air pollutants. Oxidative damage, and the alteration of NMDA receptor expression, which were induced by formaldehyde inhalation, may be the possible mechanism for gaseous formaldehyde-induced neurotoxicity.

Continuous veno-venous haemofiltration attenuates myocardial mitochondrial respiratory chain complexes activity in porcine septic shock

Increasing evidence indicates that mitochondrial dysfunction plays an important role in modulating the development of septic shock. In the present study, we investigated whether continuous veno-venous haemofiltration (CVVH) with high-volume might improve myocardial mitochondrial dysfunction in a porcine model of peritonitis-induced septic shock. Sixteen male Landrace pigs weighing 31 +/- 5 kg were randomly assigned to normal control group (n = 4), peritonitis group (n = 6) and peritonitis plus CVVH group (n = 6). All animals were anaesthetised and mechanically ventilated. After baseline examinations, the peritonitis group and the peritonitis plus CVVH group underwent induction of peritonitis. One hour later, the animals in the peritonitis plus CVVH group received treatment with high-volume CVVH. Twelve hours after treatment, the animals were sacrificed. Animals in the peritonitis group were killed 13 hours after induction of peritonitis. Peritonitis challenge induced septic shock associated with increased blood lactate and high-volume CVVH improved lactate acidosis. Compared with the peritonitis group, cardiac output, stroke volume and mean arterial pressure were better maintained in peritonitis plus CVVH group. More importantly, high-volume CVVH improved myocardial mitochondrial complex I activity (0.22 +/- 0.03 vs. 0.15 +/- 0.04, P = 0.04). These results suggest that high-volume CVVH improves haemodynamics and heart dysfunction in septic shock and the improvement may be attributed to amelioration of myocardial mitochondrial dysfunction.

New Inference Rules for Max-SAT

Exact Max-SAT solvers, compared with SAT solvers, apply little inference at each node of the proof tree. Commonly used SAT inference rules like unit propagation produce a simplified formula that preserves satisfiability but, unfortunately, solving the Max-SAT problem for the simplified formula is not equivalent to solving it for the original formula. In this paper, we define a number of original inference rules that, besides being applied efficiently, transform Max-SAT instances into equivalent Max-SAT instances which are easier to solve. The soundness of the rules, that can be seen as refinements of unit resolution adapted to Max-SAT, are proved in a novel and simple way via an integer programming transformation. With the aim of finding out how powerful the inference rules are in practice, we have developed a new Max-SAT solver, called MaxSatz, which incorporates those rules, and performed an experimental investigation. The results provide empirical evidence that MaxSatz is very competitive, at least, on random Max-2SAT, random Max-3SAT, Max-Cut, and Graph 3-coloring instances, as well as on the benchmarks from the Max-SAT Evaluation 2006.

Spectral power distribution and quantum yields of Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode

Quantum yields for multichannel transition emissions have been determined in Sm3+-doped heavy metal tellurite glass under the pumping of blue lighting emitting diode for the first time. To achieve this goal, the necessary fluorescence spectra were measured and calibrated in an integrating sphere, which was connected to a CCD detector with a 400 microm-core optical fiber. The spectral power distribution of the sample under the blue LED pumping was derived from the measured spectra firstly, and then the quantum yields for the visible emissions of Sm3+ were calculated based on the distribution and the total quantum yields in visible region is 7.55%. For accurate measurements, integrating sphere method is proved to be a reliable and reproducible way to characterize luminescence and laser materials.

Exciton dissociation in organic light emitting diodes at the donor-acceptor interface

Experimental in situ photoluminescence and transient photovoltage results show that the interface formed by N, N{'}-Bis(naphthalene-1-yl)-N, N{'}-bis(phenyl) benzidine (NPB) and tris(8-hydroxyquinoline) aluminum (Alq{3}) acts as an exciton dissociation site. Because of this dissociation effect, excitons formed in NPB at or within a diffusion length of the interface tend to dissociate before they radiatively decay to generate blue light. This suggests that the action of the "hole-blocking layer" used in indium tin oxide\NPB\hole-blocking layer\Alq{3}\aluminium to promote blue light emission from the NPB is more "exciton dissociation inhibition" than "hole blocking."

Performance of silicon nanocrystal non-volatile memory devices under various programming mechanisms

Non-volatile memory devices based on silicon nanocrystal synthesized with very low energy Si+ implantation are fabricated. Memory performance under various programming mechanisms including Fowler-Nordheim (FN), drain-bias channel-hot-electron (DCHE), and source-bias channel-hot-electron (SCHE) has been investigated. It is observed that the DCHE yields the largest memory window among the three programming mechanisms. The DCHE and SCHE have similar endurance characteristics, but the SCHE has a longer retention time than the DCHE. Both the DCHE and SCHE have a larger memory window, a better endurance and a longer retention time as compared to the FN. Explanations to the phenomena are given.

Sensitive electrochemical enzyme immunoassay microdevice based on architecture of dual ring electrodes with a sensing cavity chamber

A novel electrochemical detection architecture was investigated for enzyme immunoassay sensors. Microchips with dual-ring working and counter electrodes, and a sensing cavity chamber were made on glass slides. The glass surface of the microchip was coated by 3-aminopropyltriethoxysilane (APTES). Goat IgG, as a example, was covalently captured on APTES-modified glass surfaces through glutaraldehyde (GA) as a cross-linker. Enzyme substrate, p-aminophenyl phosphate (PAPP) was prepared by electrolysis. The enzyme conversion from home-synthetic PAPP to p-aminophenol (PAP) was examined by differential pulse voltammetry (DPV). A competitive inhibition enzyme-linked immunosorbant assay (ELISA) was designed to test the system. Experimental results demonstrate that a detection limit of 118 fg/ml of goat IgG and a dynamic range of 118 fg/ml to 1.18 ng/ml, up to five orders of magnitude could be achieved. Due to its novel architecture design and electronic detection scheme, the method can be used to fabricate portable electrochemical ELISA lab-on-chip systems. The technology could have great potential in clinical diagnostic applications.

Changes in the expression of Fas on T lymphocytes after allogeneic fetal thymus transplantation in systemic lupus erytematosus mice

BACKGROUND

Systemic lupus erythematosus (SLE) is an autoimmune disorder that can produce inflammation in many organ systems. The rate of spontaneous apoptosis in lymphocytes from human SLE patients has been reported to be increased both in vivo and in vitro. Studies of fetal thymus transplantation in an autoimmune syndrome indicate that cellular immunity can be reconstituted and regulatory T cell functions can be normalized.

OBJECTIVES

The aim of this study was to assess changes in Fas expression on T lymphocytes following fetal thymus transplant.

METHODS

(B/CxB6) F1 (H-2d/h) female F1 mice were assigned to groups designated transplantation, normal, and control. Mice in the transplantation and control groups received parental BALB/c lymphocytes intravenously. Thirty days after injection of the lymphocytes, each F1 mouse in the transplantation group received a fetal thymus graft under the right renal capsule. Mice in the control group did not receive thymus transplant and mice in the normal group received neither parental lymphocytes nor a fetal thymus graft. All mice received cyclosporin A at 2 mg/kg daily for the first 12 days after transplantation or starting on the corresponding day. Thirty days after thymus transplantation, F1 mice were sacrificed and expression of Fas in peripheral blood lymphocytes was analyzed by flow cytometry.

RESULTS

The percentage of CD4Fas+ T lymphocytes was significantly increased in the control group and the transplantation group compared with the normal group. Corresponding significant differences were observed for CD8Fas+, CD4CD25Fas', and CD45RB(low)Fas+ T lymphocytes.

CONCLUSIONS

In this study, we found that fetal thymus transplantation had a significant effect on the expression of Fas by T cell subtypes in SLE mice.