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.

Randomized controlled trial of sirolimus for renal transplant recipients at high risk for nonmelanoma skin cancer

Sirolimus has antineoplastic effects and may reduce skin cancer rates in kidney transplant patients. This prospective, multicenter, randomized, open-label, controlled trial randomized 86 kidney transplant recipients (≥1 year posttransplant) with history of nonmelanoma skin cancer (NMSC) to continue calcineurin inhibitor (CNI) or convert to sirolimus. Patients were stratified by number of NMSC lesions (0-5, 6-20) in previous year. Primary end point was number of biopsy-confirmed new NMSC lesions per patient-year. Yearly NMSC rate was significantly lower with sirolimus (1.31 vs. 2.48 lesions/patient-year; p = 0.022). Squamous cell carcinoma occurred at a lower rate in the sirolimus versus CNI group (p = 0.038); basal cell carcinoma rate was similar in both. A lower proportion of patients receiving sirolimus developed new or recurrent NMSC (56.4% vs. 80.9%; p = 0.015) or new squamous cell carcinoma (41.0% vs. 70.2%; p = 0.006). No sirolimus patients and one CNI continuation patient experienced acute rejection. Incidence of treatment-emergent adverse events was similar between groups; however, discontinuation rates related to adverse events were significantly higher with sirolimus (46.2% vs. 0%; p < 0.001). In kidney transplant recipients with history of NMSC, conversion from CNI to sirolimus reduced rates of NMSC, without increasing acute rejection risk.

An oncogenic role of miR-142-3p in human T-cell acute lymphoblastic leukemia (T-ALL) by targeting glucocorticoid receptor-α and cAMP/PKA pathways

MicroRNAs (miRNAs) are a family of 19-24 nucleotide non-coding RNAs with posttranscriptional regulatory functions. The involvement of miRNAs in normal hematopoiesis implies that deregulated miRNAs might contribute to leukemogenesis. To date, although certain miRNAs have been established a clear oncogenic role in hematological malignancies, other individual miRNAs potentially involved in human leukemogenesis still remain elusive. In this report, we showed that miR-142-3p was upregulated in human T-leukemic cell lines and primary T-leukemic cells isolated from T-cell acute lymphoblastic leukemia (T-ALL) patients and its expressive levels were correlated with patients' prognosis. Such an oncogenic role of miR-142-3p could be explained by its targeting cyclic adenosine monophosphate (cAMP)/protein kinase A (PKA) and glucocorticoid receptor alpha (GRα). High levels of miR-142-3p resulted in low levels of cAMP and weak activity of PKA, thus relieving the inhibitory effect of PKA on T-leukemic cell proliferation. Meanwhile, miR-142-3p decreased GRα protein expression by directly targeting the 3'-untranslational region of GRα mRNA, leading to glucocorticoid resistance. Transfection of the miR-142-3p inhibitor effectively converted glucocorticoid resistance, because of the resultant increase of GRα expression and PKA activity. These findings suggest that miR-142-3p is critical in T-cell leukemogenesis and may serve as a potential therapeutic target in T-ALL patients.

Effect of denosumab versus zoledronic acid on health-related quality of life in patients with metastatic breast cancer

272

Background: Patients with breast cancer and bone metastases often experience skeletal-related events (SREs) and pain, which can impact health-related quality of life (HRQoL). Denosumab is superior to zoledronic acid (ZA) in preventing SREs and more effective in delaying moderate or severe pain in patients with advanced breast cancer. We now describe the effect of denosumab or ZA treatment on HRQoL in these patients.

Methods: Patients enrolled in this double-blind, double-dummy study were randomized to receive denosumab (120 mg SC) or ZA (4 mg IV) every 4 weeks. Patients completed the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire at baseline (BL), day 8, and each monthly visit to assess overall HRQoL. Higher scores (range 0 to 108) reflect a better HRQoL. Changes in HRQoL were summarized through month 18, when 30% of patients had died or dropped out due to disease progression or withdrawal of consent. Increases or decreases of ≥ 5 points in the FACT-G total score were considered clinically meaningful. Pain was evaluated by the Brief Pain Inventory–Short Form (BPI-SF). HRQoL was assessed in subgroups with no/mild pain or moderate/severe pain at BL.

Results: The BL mean (SD) FACT-G score was similar for denosumab (n = 956) 72.7 (16.4) and ZA (n = 952) 73.6 (16.5) groups and increased from BL to month18 for both groups reflecting improved HRQoL. An average of 3.2% more (range 0.9% to 6.8%) denosumab-treated patients than ZA-treated patients experienced a ≥ 5-point increase in HRQoL from months 1 to 18. Fewer denosumab than ZA-treated patients reported a ≥ 5-point decrease in HRQoL (average 2.7% fewer; range 0.6% to 5.8%). Among patients with no/mild pain at BL, an average of 4.1% more (range -0.6% to 9.3%) denosumab-treated patients had a ≥ 5-point increase in FACT-G score from month 4 to 18. In this same subgroup, fewer denosumab-treated patients had a ≥ 5-point decrease in HRQoL over 18 months (average 2.4% fewer; range -4.4% to 6.3%). Similar patterns in FACT-G scores were noted for the subgroup with moderate/severe pain at BL.

Conclusions: In patients with advanced breast cancer, a greater proportion treated with denosumab than ZA had a meaningful improvement in HRQoL regardless of BL pain level.

Clinical outcomes following switch from venlafaxine ER to desvenlafaxine in nonresponders and responders

OBJECTIVE

This post hoc analysis examined efficacy and tolerability of open-label desvenlafaxine in patients with major depressive disorder switched from blinded placebo, venlafaxine extended release (ER), or desvenlafaxine.

RESEARCH DESIGN AND METHODS

Patients who completed 8 weeks of double-blind therapy with placebo (n = 176), venlafaxine ER (n = 175), or desvenlafaxine (n = 143) enrolled in a 10-month, open-label extension study and received desvenlafaxine 200 to 400 mg/d. Efficacy (17-item Hamilton Depression Rating Scale [HDRS(17)]) was assessed separately for nonresponders and responders to double-blind treatment. Tolerability during the first month of open-label desvenlafaxine was assessed.

RESULTS

Among nonresponders (n = 134) to double-blind placebo, venlafaxine ER, and desvenlafaxine, mean decreases in HDRS(17) scores were -10.9, -7.3, and -7.7, respectively; HDRS(17) response rates were 67%, 53%, and 48%, respectively. Although responders (n = 360) to double-blind placebo, venlafaxine ER, and desvenlafaxine had more modest decreases on the HDRS(17), response rates were higher (84%, 87%, and 83%, respectively). Rates of adverse events were highest during week 1, and decreased afterward for the remainder of the first month of treatment.

CONCLUSIONS

Among nonresponders to 8 weeks of double-blind venlafaxine ER, desvenlafaxine, or placebo, 48% to 67% subsequently responded to open-label desvenlafaxine. Over 80% of responders to double-blind therapy maintained response on open-label desvenlafaxine. The switch from venlafaxine ER to desvenlafaxine was well tolerated.

Wld(S) protects against peripheral neuropathy and retinopathy in an experimental model of diabetes in mice

AIMS/HYPOTHESIS

We aimed to evaluate the effect of the mutant Wld(S) (slow Wallerian degeneration; also known as Wld) gene in experimental diabetes on early experimental peripheral diabetic neuropathy and diabetic retinopathy.

METHODS

The experiments were performed in four groups of mice: wild-type (WT), streptozotocin (STZ)-induced diabetic WT, C57BL/Wld(S) and STZ-induced diabetic C57BL/Wld(S). In each group, intraperitoneal glucose and insulin tolerance tests were performed; blood glucose, glycated haemoglobin and serum insulin were monitored. These mice were also subjected to the following behavioural tests: grasping test, hot-plate test and von Frey aesthesiometer test. For some animals, sciatic-tibial motor nerve conduction velocity, tail sensory nerve conduction velocity and eye pattern electroretinogram were measured. At the end of the experiments, islets were isolated to detect glucose-stimulated insulin secretion, ATP content and extent of apoptosis. The NAD/NADH ratio in islets and retinas was evaluated. Surviving retinal ganglion cells were estimated by immunohistochemistry.

RESULTS

We found that the Wld(S) gene is expressed in islets and protects beta cells against multiple low doses of STZ by increasing the NAD/NADH ratio, maintaining the ATP concentration, and reducing apoptosis. Consistently, significantly higher insulin concentrations, lower blood glucose concentrations, and better glucose tolerance were observed in Wld(S) mice compared with WT mice after STZ treatment. Furthermore, Wld(S) alleviated abnormal sensory responses, nerve conduction, retina dysfunction and reduction of surviving retinal ganglion cells in STZ-induced diabetic models.

CONCLUSIONS/INTERPRETATION

We provide the first evidence that expression of the Wld(S) gene decreases beta cell destruction and preserves islet function in STZ-induced diabetes, thus revealing a novel protective strategy for diabetic models.

Copper metallization for current very large scale integration

As silicon technology scaling progresses to the 32 nm node or even further, the design on the propagation of electromagnetic signals becomes increasingly appealing due to their unyielding constraints on interconnect delay. Because of its high conductivity and electromigration resistance, Cu is now the interconnect materials in current VLSI. To ensure the signal propagation via the Cu interconnects upon the increasingly reduction in the interconnect width, related issues on Cu interconnects, such as electron scattering at surfaces and grain boundaries, electromigration failure and surface oxidation, still need to be further understood and addressed. Besides this, the performance of low-k dielectrics and reliable barrier structures, which are also much important among the device parts, are required to be further improved to minimize the signal delay and to prevent penetration of different materials, respectively. On the basis of the paper published at Recent Patent on Nanotechnology 2007; 1: 193-209, this review will focus on recent patents and some studies on Cu metallization including Cu interconnect wires, low-k dielectrics and related barrier materials as well as manufacturing techniques in VLSI, which are one of the most essential concerns in microelectronic industry and decide further development of VLSI. This review will benefit for the design of the Cu metallization in the current VLSI.

Induction of the glucocorticoid-induced leucine zipper gene limits the efficacy of dendritic cell vaccines

Dendritic cell (DC) vaccines have shown great promise in generating anti-tumor immune responses but have generally fallen short of producing durable cures. Determining mechanisms by which these vaccines fail will provide one strategy towards improving their success. Several manipulations of DCs have improved their migration and longevity, but the immune inhibitory environment surrounding tumors provides a powerful suppressive influence. To determine the mechanisms by which DCs at the site of the tumor convert to a suppressive phenotype, we evaluated pathways in DCs that become expressed at the tumor site. Our results revealed that tumors lead to induction of the glucocorticoid induced leucine zipper (GILZ) gene in DCs, and that this gene is critical for the development of tumor induced tolerance of both DCs and T cells. Previous data suggested that GILZ is a pivotal gene in the balance between activation and tolerance of DCs. Our new data show that GILZ is highly upregulated in DCs in the tumor microenvironment in vivo and that blockade of this gene in DC vaccines significantly improves long term survival. These results suggest that GILZ may be an ideal candidate gene to target for novel immune-based tumor therapies.

Body fat distribution and their associations with cardiovascular risk, insulin resistance and β-cell function: are there differences between men and women?

OBJECTIVE

The objective was to examine the independent and gender-specific effects of WC and BMI on CVD risk factors, insulin resistance and β-cell function.

DESIGN

A cross-sectional study of 2931 adults aged 20-79 years was carried out in Fujian province by multi-stratified sampling from July 2007 to May 2008. Gender-specific differences of WC and BMI on CVD risk factors, insulin resistance and β-cell function were displayed jointly by WC and BMI tertiles. The homeostasis model assessment of insulin resistance (HOMA-IR) index and the quantitative insulin-sensitivity check index (QUICKI): l/(log G0 ± log I0) were used to estimate insulin sensitivity; insulin secretion was assessed using the HOMA-β index; β-cell function was quantified as the ratio of the incremental insulin to glucose responses over the first 30 min during the OGTT (△I30/△G30). The oral disposition index (DIo) was calculated as ΔI(30) /ΔG(30) × 1/fasting insulin. The Matsuda index is defined as 10,000/sqrt (FBG × FPI × [G × I]) where FPG is fasting glucose, FPI is fasting insulin, G is mean glucose during the OGTT (calculated from glucose samples at 0, 30, and 120 min), and I is mean insulin during the OGTT (calculated from insulin samples at 0, 30, and 120 min).

RESULTS

Waist circumference and BMI correlated with each other in both men (0.756, p < 0.001) and women (0.728, p < 0.001). The two indexes were independently associated with CVD risk factors (such as hypertension, metabolic syndrome, and dyslipidaemia) in both men and women. BMI was better than WC in assessing the risk of diabetes in men (p = 0.003 for BMI, and p = 0.234 for WC), while WC was better than BMI in predicting diabetes in women (p < 0.001 for WC, and p = 0.831 for BMI). There were significant associations between BMI and insulin resistance or β-cell function even after adjustment for WC except for DIo in male subjects, but WC only associated with HOMA-IR positively or the Matsuda index and QUICKI negatively after adjustment for BMI. For women, associations between WC and insulin resistance or β-cell function remained strong even after adjustment for BMI besides DIo. However, there were no independent relations of BMI to insulin resistance and β-cell function except for Matsuda index with a significant negative association after adjustment for WC in women.

CONCLUSION

Body mass index and WC were independently associated with CVD risk factors. There were differences in the gender-specific relevance of measures of body fat distribution in assessing the insulin resistance, β-cell function and thus the risk of diabetes. Therefore, WC should be measured in addition to BMI to assess CVD risk accurately and implement efficient treatment strategies.

The correlation between the oral glucose tolerance test 30-minutes plasma glucose and risk factors for diabetes and cardiovascular diseases: a cross-sectional epidemiological study of diabetes in Fujian Province in the South-East of China

OBJECTIVE

To investigate the correlation between abnormal oral glucose tolerance test (OGTT) 30-min plasma glucose (PG) and risk factors and metabolic abnormalities of diabetes and cardiovascular diseases (CVD).

METHODS

Participants (no.=2457) underwent a physical examination, blood biochemistry examination, OGTT, and a 12-lead electrocardiogram. We measured fasting PG (FPG) and PG at 30 min (30minPG) and 1 h (1hPG) of the OGTT. The association between an increase in 30minPG (by 1 SD) and the metabolic abnormalities of diabetes and CVD such as hypertension, overweight and obesity, central obesity, and hyperlipidemia; osteoporosis was assessed by logistic regression analysis after controlling for FPG and 2hPG.

RESULTS

This analysis showed that an increase of 30minPG by 1 SD (1.92 mmol/l) significantly increased the risk of chronic metabolic abnormalities in diabetes and CVD such as hypertension, overweight, and obesity, central obesity, hyperlipidemia, and osteoporosis. Stepwise multiple regression analysis also showed that 30minPG was significantly correlated with male gender, smoking, FPG, 2hPG, total cholesterol, waist/hip ratio, and blood pressure.

CONCLUSIONS

An elevation of 30minPG increased the risk of diabetes and CVD. The increased risk was independent of FPG, 2hPG, age, sex, and smoking status.

Magnetic Resonance Imaging Estimation of Longitudinal Relaxation Rate Change (ΔR1) in Dual Gradient Echo Sequences Using an Adaptive Model

Magnetic Resonance Imaging (MRI) estimation of contrast agent concentration in fast pulse sequences such as Dual Gradient Echo (DGE) imaging is challenging. An Adaptive Neural Network (ANN) was trained with a map of contrast agent concentration estimated by Look-Locker (LL) technique (modified version of inversion recovery imaging) as a gold standard. Using a set of features extracted from DGE MRI data, an ANN was trained to create a voxel based estimator of the time trace of CA concentration. The ANN was trained and tested with the DGE and LL information of six Fisher rats using a K-Fold Cross-Validation (KFCV) method with 60 folds and 10500 samples. The Area Under the Receiver Operator Characteristic Curve (AUROC) for 60 folds was used for training, testing and optimization of the ANN. After training and optimization, the optimal ANN (4:7:5:1) produced maps of CA concentration which were highly correlated (r =0.89, P < 0.0001) with the CA concentration estimated by the LL technique. The estimation made by the ANN had an excellent overall performance (AUROC = 0.870).

Naloxone in the management of hepatic encephalopathy

BACKGROUND/AIM

This study aimed to assess the effectiveness and safety of naloxone in the management of hepatic encephalopathy (HE).

METHODS

Cochrane collaboration methodology was used in a meta-analysis of randomized controlled trials of naloxone therapy for HE.

RESULTS

Seventeen randomized trials were identified with 15 studies involving 1054 patients meeting criteria for inclusion. Naloxone use was associated with a significant improvement in HE [relative risk (RR) 1.46; 95% confidence interval (CI) 1.27-1.67; P = 0.0005]. This comparison showed statistical heterogeneity (P < 0.10, and χ2 = 44.93). Subgroup analysis indicated naloxone administered parenterally by intermittent or continuous infusions to be effective (RR 1.34; 95% CI 1.17-1.53; P < 0.0001). A significant in trials by infusion route (RR 1.42; 95% CI 1.19-1.69; P < 0.0001) interaction was observed.

CONCLUSIONS

Naloxone may improve HE. However, published data are limited.

Abstract P1-13-05: The Effect of Treatment with Denosumab or Zoledronic Acid on Health-Related Quality of Life in Patients with Metastatic Breast Cancer

Background: Patients with breast cancer and bone metastases often experience skeletal-related events (SREs) and pain, which may impact health-related quality of life (HRQoL). Denosumab is a fully human monoclonal antibody against RANKL shown to be superior in delaying/preventing SREs and more effective in delaying moderate or severe pain in patients with advanced breast cancer compared with zoledronic acid (ZA). Previously reported results from this study population showed that both denosumab and ZA patients showed improvement or maintenance in HRQoL relative to baseline (BL), and a greater proportion of denosumab-treated patients had a clinically meaningful improvement in HRQoL. We now describe the effect of denosumab and ZA treatment on HRQoL among patients with varying degrees of pain at BL.

Methods: Enrolled patients received subcutaneous (SC) denosumab 120 mg or intravenous (IV) ZA 4 mg every 4 weeks in a double-blind, double-dummy fashion. Pain was evaluated using the Brief Pain Inventory — Short Form (BPI). Patients were divided into 2 subgroups based on the level of pain reported at BL: no/mild pain or moderate/severe pain. Patients completed the Functional Assessment of Cancer Therapy-General (FACT-G) questionnaire at BL, day 8, and before each monthly visit to assess overall HRQoL. Higher scores (range 0 to 108) represent better HRQoL. Improvement, maintenance, and worsening of HRQoL were assessed through month 18, when 30% of patients had dropped out due to death, disease progression, or withdrawal of consent. A change of ≥5 points (increase or decrease) in the FACT-G total score was considered a meaningful improvement.

Results: Among patients who reported no/mild pain at baseline, more denosumab-treated patients had a ≥5-point increase in their FACT-G score from month 4 onwards. Over the 18 month period, an average of 4.1% more (range: −0.6% to 9.3%) denosumab-treated patients experienced meaningful improvement in HRQoL than ZA-treated patients. There were also fewer denosumab-treated patients experiencing ≥5-point decrease in HRQoL over 18 months (average of 2.4% fewer [range:-4.4% to 6.3% fewer]). Similar patterns were also noted for patients with moderate/severe pain at baseline. An average of 3.0% more (range:-1.7% to 7.9%) denosumab-treated patients had ≥5-point increase in FACT-G scores compared with ZA-treated patients over 18 months. A lower proportion of denosumab-treated patients (3.5% fewer [range: −1.1% to 11.5% fewer]) than ZA-treated patients had a decrease ≥5-points in their FACT-G score over 18 months.

Conclusion: In patients with breast cancer and bone metastases, a greater proportion treated with denosumab than ZA had a meaningful improvement in HRQoL regardless of their pain level at BL.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-13-05.

Association of single-nucleotide polymorphisms in HLA class II/III region with knee osteoarthritis

OBJECTIVE

A genome-wide association study and a replication using Japanese, Spanish and Greek Caucasian populations have recently indicated two single-nucleotide polymorphisms (SNPs) (rs7775228 and rs10947262) associated with knee Osteoarthritis (OA) susceptibility. We have further evaluated the association in knee OA subjects from Han Chinese and Australian Caucasian origin.

METHODS

Two independent case-control association studies were performed using Han Chinese and Australian Caucasian populations. The two SNPs were genotyped in patients who had primary symptomatic knee OA with radiographic confirmation and/or received total knee replacement surgery as well as in matched controls. They were subjected to statistic analyses.

RESULTS

A total of 991 OA patients and 1536 controls were genotyped. No significant difference was detected in genotype or allele frequencies of the two SNPs between knee OA and control groups in the two populations (all P>0.05). The association was also negative even after stratification by sex, body mass index (BMI) and Kellgren/Lawrence scores. The significant heterogeneity was detected between Chinese and Japanese (both P<0.05). In the Caucasian samples, no significant heterogeneity was detected (both P>0.05). The result of meta-analysis showed significant association between knee OA and rs10947262 in total subjects [summary OR=1.26, 95%confidence intervals (CI)=1.07-1.27, P=3 × 10(-8)] and in Caucasian samples (summary OR=1.28, 95%CI=1.04-1.57, P=0.02).

CONCLUSION

We demonstrated no association between the two SNPs in human leukocyte antigen (HLA) class II/III region and knee OA in Han Chinese population. A significant association was detected between SNP rs10947262 and knee OA in Caucasian subjects. Further replication studies are required to identify the impact of controversial association.

Comparison of the safety and efficacy of cyclosporine minimization versus cyclosporine elimination in de novo renal allograft patients receiving sirolimus

The safety and efficacy of concentration-controlled use of sirolimus (SRL) and cyclosporine (CsA) followed by CsA minimization (CsAm) or elimination (CsAe) beginning at week 13 was compared in a phase 4, open-label, randomized (1:1) trial of renal transplant recipients enrolled between March 2004 and November 2005. The primary endpoint was renal function, measured at 12 months using the Nankivell formula, in patients remaining on therapy. Though a total enrollment of 140 patients in each group was planned to provide an 80% power to detect a difference in means, only 207 subjects were enrolled in this study. Demographic characteristics were similar between groups, with 98.1% recipients of first grafts, 69.1% from living donors, and 7.2% diabetics. At 12 months, there were no differences in renal function (61.08 vs 65.24 mL/min, P = .132); incidence of biopsy-confirmed acute rejection (14.3% vs 22.5%, P = .152); and patient (89.5% vs 92.2%, P = .632), graft (87.6% vs 88.2%, P = .999), and death-censored graft (98.1% vs 94.1%, P = .166) survivals between CsAm and CsAe groups, respectively. There were no differences in the overall rate of study-drug discontinuation (32.4% vs 36.3%, P = .562) but more patients discontinued because of lack of efficacy/graft loss in the CsAe group (4.8% vs 14.7%, P = .018). This study was underpowered to demonstrate the superiority of one regimen over the other. In summary, SRL immunotherapy combined with CsA minimization or elimination showed comparative safety and efficacy. Both regimens offer potential treatment options for de novo renal allograft recipients.

Highly Efficient Near-IR Photoluminescence of Er Immobilized in Mesoporous SBA-15

SiO(2) mesoporous molecular sieve SBA-15 with the incorporation of erbium ions is studied as a novel type of nanoscopic composite photoluminescent material in this paper. To enhance the photoluminescence efficiency, two schemes have been used for the incorporation of Er(3+) where (1) Er(3+) is ligated with bis-(perfluoromethylsulfonyl)-aminate (PMS) forming Er(PMS)(x)-SBA-15 and (2) Yb(3+) is codoped with Er(3+) forming Yb-Er-SBA-15. As high as 11.17 × 10(-21)cm(2) of fluorescent cross section at 1534 nm and 88 nm of "effective bandwidth" have been gained. It is a 29.3% boost in fluorescent cross section compared to what has been obtained in conventional silica. The upconversion coefficient in Yb-Er-SBA-15 is relatively small compared to that in other ordinary glass hosts. The increased fluorescent cross section and lowered upconversion coefficient could benefit for the high-gain optical amplifier. Finally, the Judd-Ofelt theory has also been used for the analyses of the optical spectra of Er(PMS)(x)-SBA-15.

Electron scattering and electrical conductance in polycrystalline metallic films and wires: impact of grain boundary scattering related to melting point

For electrical conductance in polycrystalline metallic films and wires, the reflection coefficient of electrons at grain boundaries is explored and found to be proportional to the square root of the melting points of metals. As validated by available experimental results, this exploration enables classical models to take an essential role in theoretically predicting the electrical conductance of low-dimensional metals. One thus sees that the mechanism dominating the suppression of electrical conductance is transformed from the surface scattering into the grain boundary scattering as the ratio of film thickness (or wire diameter) to grain size rises. Furthermore, the impact of grain boundary scattering becomes less important for metals with lower melting points.

Novel and recurrent TRPV4 mutations and their association with distinct phenotypes within the TRPV4 dysplasia family

BACKGROUND

Mutations in TRPV4, a gene that encodes a Ca(2+) permeable non-selective cation channel, have recently been found in a spectrum of skeletal dysplasias that includes brachyolmia, spondylometaphyseal dysplasia, Kozlowski type (SMDK) and metatropic dysplasia (MD). Only a total of seven missense mutations were detected, however. The full spectrum of TRPV4 mutations and their phenotypes remained unclear.

OBJECTIVES AND METHODS

To examine TRPV4 mutation spectrum and phenotype-genotype association, we searched for TRPV4 mutations by PCR-direct sequencing from genomic DNA in 22 MD and 20 SMDK probands.

RESULTS

TRPV4 mutations were found in all but one MD subject. In total, 19 different heterozygous mutations were identified in 41 subjects; two were recurrent and 17 were novel. In MD, a recurrent P799L mutation was identified in nine subjects, as well as 10 novel mutations including F471del, the first deletion mutation of TRPV4. In SMDK, a recurrent R594H mutation was identified in 12 subjects and seven novel mutations. An association between the position of mutations and the disease phenotype was also observed. Thus, P799 in exon 15 is a hot codon for MD mutations, as four different amino acid substitutions have been observed at this codon; while R594 in exon 11 is a hotspot for SMDK mutations.

CONCLUSION

The TRPV4 mutation spectrum in MD and SMDK, which showed genotype-phenotype correlation and potential functional significance of mutations that are non-randomly distributed over the gene, was presented in this study. The results would help diagnostic laboratories establish efficient screening strategies for genetic diagnosis of the TRPV4 dysplasia family diseases.

Inhibitory regulation of acid-sensing ion channel 3 by zinc

Acid-sensing ion channel 3 (ASIC3) is a proton-gated, voltage-insensitive Na(+) channel that is expressed primarily in peripheral sensory neurons and plays an important role in pain perception, particularly as a pH sensor following cardiac ischemia. We previously reported that ASIC3 currents are not affected by zinc at nanomolar concentrations. In this study, we examined the potential role of micromolar zinc in the regulation of ASIC3. In CHO cells expressing ASIC3, we found that ASIC3 currents triggered by dropping the pH from 7.4 to 6.0 were inhibited by pretreatment with zinc in a concentration-dependent manner; the half-maximum inhibitory concentration of zinc was 61 muM. ASIC currents activated by a relatively small drop in pH from 7.4 to 7.2 or 7.0 were also subject to inhibition by zinc. The inhibition was fast and pH independent, and occurred within a relatively narrow range of zinc concentrations between 30 and 300 muM. Further, increasing extracellular Ca(2+) concentrations from 2 to 10 mM failed to affect inhibition of ASIC3 currents by zinc. Experimentally elevating intracellular zinc levels did not affect the inhibition of ASIC3 currents by equal concentrations of extracellular zinc, and modification of cysteine or histidine residues had no effect on the inhibition of ASIC3 currents by zinc. These collective results suggest that zinc is an important regulator of ASIC3 at physiological concentrations, that zinc inhibits ASIC3 in a pH- and Ca(2+)-independent manner, and that inhibition of ASIC3 currents is dependent upon the interaction of zinc with extracellular domain(s) of ASIC3.

Effects of intermixing on modulation p-doped quantum dot superluminescent light emitting diodes

Different capping of quantum dot (QD) materials is known to produce different degrees of intermixing during a post-growth thermal annealing process. We report a study of the effect of different degrees of intermixing on modulation beryllium doped quantum dot superluminescent light emitting diodes (QD-SLEDs). The intermixed QD-SLEDs show high device performance whilst achieving a large central emission wavelength shift of approximately 100nm compared to the as-grown device. The evolution of the emission spectra and power with drive current suggest a transition from QD-like to QW-like behavior with increasing degree of intermixing. A selective area intermixed QD-SLED is demonstrated, and with optimized differential intermixing, such structures should allow ultra-broadband sources to be realized.

Effect of Saliva Contamination and Decontamination on Bovine Enamel Bond Strength of Four Self-etching Adhesives

Salivary contamination before and after priming could significantly reduce the enamel bond strength of self-etching adhesives. Proper isolation should be performed before and during application of the adhesives and placement of the resin composite. Thorough water-spraying could significantly improve the μTBS of saliva-contaminated enamel.

Reply to comment on 'Modelling of surface energies of elemental crystals'

In reply to the comment by Luo et al, our theoretical model for the surface energy of elemental crystals is further developed to improve the prediction accuracy of the surface energy of the high-Miller-index facets. It is considered that the previous predicted unit surface area could not denote the actual one since the facets now are uneven. With the modification, the accuracy for the prediction of surface energy in units of J m(-2) is improved.

Characterization of acid-sensing ion channels in medium spiny neurons of mouse striatum

Acid-sensing ion channels (ASICs) regulate synaptic activities and play important roles in neurodegenerative diseases. They are highly expressed in the striatum, where medium spiny neurons (MSNs) are a major population. Given that the properties of ASICs in MSNs are unknown, in this study, we characterized ASICs in MSNs of the mouse striatum. A rapid drop in extracellular pH induced transient inward currents in all MSNs. The pH value for half-maximal activation was 6.25, close to that obtained in homomeric ASIC1a channels. Based on psalmotoxin 1 and zinc sensitivity, ASIC1a (70.5% of neurons) and heteromeric ASIC1a-2 channels (29.5% of neurons) appeared responsible for the acid-induced currents in MSNs. ASIC currents were diminished in MSNs from ASIC1, but not ASIC2, null mice. Furthermore, a drop in pH induced calcium influx by activating homomeric ASIC1a channels. Activation of ASICs increased the membrane excitability of MSNs and lowering extracellular Ca2+ potentiated ASIC currents. Our data suggest that the homomeric ASIC1a channel represents a majority of the ASIC isoform in MSNs. The potential function of ASICs in the striatum requires further investigation.

A p-type-doped quantum dot superluminescent LED with broadband and flat-topped emission spectra obtained by post-growth intermixing under a GaAs proximity cap

Broadband superluminescent light emitting diodes are realized by a post-growth annealing process, on modulation p-doped multiple InAs/InGaAs/GaAs quantum dot layer structures, under a GaAs proximity cap. The device exhibits a large and flat emission with spectral width up to 132 nm at 2 mW. This is mainly attributed to the reduction of the energy separation between the ground state and the excited state, in addition to the optical quality of the intermixed modulation p-doped quantum dot materials being comparable to that of the as-grown sample.