Surface Disordering and Nitrogen Loss in GaN under Ion Bombardment

The damage build-up and amorphization behavior in wurtzite GaN films under a wide range of implant conditions are studied by Rutherford backscattering / channeling spectrometry, transmission electron microscopy, and cathodoluminescence spectroscopy. A strong surface peak of lattice disorder, in addition to the expected damage peak in the region of the maximum of nuclear energy loss, has been observed for all implant conditions of this study. Capping of GaN with SiOx and SixNy layers prior to implantation does not eliminate surface disordering. This may suggest that nitrogen loss is not the main reason for the observed enhanced surface disorder, but, rather, the GaN surface acts as a strong sink for migrating point defects. However, pronounced loss of N during ion bombardment is observed for high dose implantation when the near-surface region is amorphized. Moreover, after amorphization, annealing at temperatures above about 400°C leads to complete decomposition of the near-surface layer.

A novel sheep vertebral bone defect model for injectable bioactive vertebral augmentation materials

New injectable bone substitutes have been developed that are, unlike polymethylmethacrylate, biologically active and have an osteogenic effect leading to osteogenesis and bone remodeling for vertebroplasty or kyphoplasty. In this study, we developed a sheep vertebral bone defect model to evaluate the new bioactive materials and assessed the feasibility of the model in vivo. Bone voids were experimentally created on lumbar vertebrae L2-L5 with L1 and L6 left intact as a normal control in mature sheep. The defect vertebrae L2-L5 in each sheep were randomized to receive augmentation with calcium phosphate cement (CPC) or sham. Vertebrae (L1-L6) were collected after 2 and 24 weeks of the cement augmentation and their strength and stiffness, as well as osseointegration activity and biodegradability, were evaluated. Finally, CPC significantly improved the strength and stiffness of vertebrae but did not yet restore it to the normal level at 24 weeks. Osteogenesis occurred at a substantially high level after 24 weeks of CPC augmentation or sham. Therefore, the sheep vertebral model with one void, 6.0 mm in diameter and 15.0 mm in depth, is replicable and can be used for evaluating the new injectable bioactive materials in vertebral augmentation or reconstruction.

Establishment of a paclitaxel resistant human breast cancer cell strain (MCF-7/Taxol) and intracellular paclitaxel binding protein analysis

Multidrug resistance of tumours is one of the most important factors that leads to chemotherapy failure. A multidrug-resistant breast cancer cell line, MCF-7/Taxol, was established from the drug-sensitive parent cell line MCF-7. The biological properties of MCF-7/Taxol, including its drug resistance profile and profile of paclitaxel binding proteins, were analysed and compared with the parent cell line. A number of paclitaxel binding proteins were present in MCF-7 cells but absent from MCF-7/Taxol cells, namely heat shock protein 90, actinin and dermcidin precursor. The identification of differential paclitaxel binding proteins between the multidrug-resistant MCF-7/Taxol cell line and the parent drug-sensitive cell line MCF-7 provides insight into possible mechanisms involved in resistance to these chemotherapy drugs.

Novel growth and properties of GaAs nanowires on Si substrates

Straight, vertically aligned GaAs nanowires were grown on Si(111) substrates coated with thin GaAs buffer layers. We find that the V/III precursor ratio and growth temperature are crucial factors influencing the morphology and quality of buffer layers. A double layer structure, consisting of a thin initial layer grown at low V/III ratio and low temperature followed by a layer grown at high V/III ratio and high temperature, is crucial for achieving straight, vertically aligned GaAs nanowires on Si(111) substrates. An in situ annealing step at high temperature after buffer layer growth improves the surface and structural properties of the buffer layer, which further improves the morphology of the GaAs nanowire growth. Through such optimizations we show that vertically aligned GaAs nanowires can be fabricated on Si(111) substrates and achieve the same structural and optical properties as GaAs nanowires grown directly on GaAs(111)B substrates.

Improved removal of arsenic from groundwater using pre-corroded steel and iron tailored granular activated carbon

The authors have combined corrosion of steel fittings or perforated sheets with granular activated carbon (GAC) that had been pre-treated with Fe(III)-citrate, to produce an innovative and low-maintenance technique for removing arsenic from groundwater. Removal of arsenic was measured using two GAC column configurations: rapid small scale column tests (RSSCT's) and mini-column tests. Independent variables included pH, pre-corrosion procedure, and idling of the column (i.e. intentionally stopping flow for defined times in order to create reducing conditions). Use of corroded steel plus pre-treated GAC removed arsenic to below 10 microg/L for up to 248,000 bed volumes (BV) at pH 6, compared to 7,000 BVs for pre-treated GAC without pre-corroded steel. Performance was not as good at pH 6.5 or 7.5. Idling the system recovered the iron corrosion ability by reducing the passive Fe(III) layer on pre-corroded steel surface, as a result the BVs to arsenic breakthrough was doubled. But idling also caused brief periods of arsenic and iron release after restart, due to reductive dissolution of arsenic-containing ferric oxides. GAC was also effective as filtration media for removal of iron (hydr)oxide particles (and associated arsenic) that was released from the pre-corroded iron.

Molecular characterization and expression analysis of the IFN-gamma related gene (IFN-gammarel) in grass carp Ctenopharyngodon idella

Interferon gamma (IFN-gamma), the only member of the type II class of interferons, has been identified in teleost fish. In addition to the IFN-gamma gene, fish possess an IFN-gamma related gene (IFN-gammarel) neighbouring the authentic IFN-gamma gene in the genome. In the present study, the cDNA sequence encoding 167 amino acids of IFN-gammarel and its genomic organization were identified in grass carp Ctenopharyngodon idella. The predicted protein sequence of grass carp IFN-gammarel (gcIFN-gammarel) showed 63% and 50% identities to zebrafish and common carp IFN-gammarel (previously termed as IFN-gamma1), respectively. The IFN-gammarel gene consists of 4 exons, with 3 intervening introns, spanning approximately 2kb of genomic sequence. The gcIFN-gammarel gene did not contain any polymorphic DNA repeats in the introns. Realtime PCR analysis showed that grass carp reovirus induced a high and long lasting (from days 1 to 7) expression of gcIFN-gammarel in spleen. The expression of gcIFN-gammarel in blood, head kidney, trunk kidney and spleen was also increased by bacterial peptidoglycan (PGN), lipopolysaccharide (LPS) and the interferon inducer polyI:C. The highest induction of gcIFN-gammarel expression by PGN was observed in spleen, then in blood and head kidney. Further analysis of the expression patterns of gcIFN-gammarel and PGN receptors, nucleotide oligomerization domains (NOD) 1 and 2, may suggest that IFN-gammarel was possibly activated in a NOD2-dependent mechanism.

Rainbow trout interleukin-2: cloning, expression and bioactivity analysis

In this study the rainbow trout (Oncorhynchus mykiss) interleukin-2 (IL-2) cDNA has been cloned, and its expression and bioactivity analysed in head kidney leucocytes. The IL-2 precursor encoded an open reading frame of 429 bp, that translates into a predicted protein of 142 aa, with a 20 aa signal peptide. The trout IL-2 had moderate protein homology (30.9% identity/48.3% similarity) with Fugu IL-2, the only IL-2 homologue identified in fish to date, with lower homology to avian (17.8% identity/23.2% similarity) and mammalian (34.2 identity/46.5% similarity) IL-2s. IL-2 expression was induced by the T cell mitogen PHA and by the mixed leucocyte reaction, where leucocytes from pairs of fish were cultured together for four days. Expression was also induced in vivo during bacterial (Yersinia ruckeri) infection. The Escherichia coli produced recombinant IL-2 was shown to increase the expression of two transcription factors, STAT5 and Blimp-1, known to be involved in IL-2 signalling in mammals, as well as IFN-gamma, gIP and IL-2 itself. The potential signalling pathways involved and possible use as an adjuvant for fish vaccines are discussed.

The search for the IFN-gamma receptor in fish: Functional and expression analysis of putative binding and signalling chains in rainbow trout Oncorhynchus mykiss

Interferons (IFNs), consisting of three major subfamilies, type I, type II (gamma) and type III (lambda) IFN, activate vertebrate antiviral defences once bound to their receptors. The three IFN subfamilies bind to different receptors, IFNAR1 and IFNAR2 for type I IFNs, IFNgammaR1 and IFNgammaR2 for type II IFN, and IL-28R1 and IL-10R2 for type III IFNs. In fish, although many types I and II IFN genes have been cloned, little is known about their receptors. In this report, two putative IFN-gamma receptor chains were identified and sequenced in rainbow trout (Oncorhynchus mykiss), and found to have many common characteristics with mammalian type II IFN receptor family members. The presented gene synteny analysis, phylogenetic tree analysis and ligand binding analysis all suggest that these molecules are the authentic IFNgammaRs in fish. They are widely expressed in tissues, with IFNgammaR1 typically more highly expressed than IFNgammaR2. Using the trout RTG-2 cell line it was possible to show that the individual chains could be differentially modulated, with rIFN-gamma and rIL-1beta down regulating IFNgammaR1 expression but up regulating IFNgammaR2 expression. Over-expression of the two receptor chains in RTG-2 cells revealed that the level of IFNgammaR2 transcript was crucial for responsiveness to rIFN-gamma, in terms of inducing gammaIP expression. Transfection experiments showed that the two putative receptors specifically bound to rIFN-gamma. These findings are discussed in the context of how the IFNgammaR may bind IFN-gamma in fish and the importance of the individual receptor chains to signal transduction.

A Comparison of Proximal Femoral Nail Antirotation and Dynamic Hip Screw Devices in Trochanteric Fractures

This prospective, randomized study compared the functional outcome and complications associated with a proximal femoral nail antirotation (PFNA) device with those of a traditional extramedullary device, the dynamic hip screw (DHS), in patients with trochanteric fracture. A total of 121 patients were randomized to the PFNA group ( n = 58) or the DHS group ( n = 63). Perioperative information and complications were recorded, and assessments of functional outcome were made. The DHS group required a longer operative time and was associated with greater blood loss than the PFNA group. The re-operation rate was lower in the PFNA group compared with the DHS group, especially in patients with unstable fractures, although there was no statistically significant difference in the overall complication rate between the two groups. There were no significant differences in functional outcome between the PFNA and the DHS groups. In conclusion, the PFNA device is useful in the treatment of trochanteric fractures.

High quality InAs quantum dots grown on patterned Si with a GaAs buffer layer

Ordered and dense InAs quantum dots grown on patterned Si(100) with a thin GaAs buffer layer have been investigated by transmission electron microscopy and electron energy loss spectroscopy. {111} faceted InAs quantum dots with good crystallinity were observed on top of the underlying GaAs buffer layer. It was revealed that the GaAs buffer layer and the lateral expansion of InAs have played key roles in releasing the misfit strain between InAs and Si and suppressing the formation of lattice defects in InAs quantum dots. These results suggest a possible pathway for the strain relaxation in the formation of quantum dots.

The effect of V/III ratio and catalyst particle size on the crystal structure and optical properties of InP nanowires

InP nanowires were grown on 111B InP substrates by metal-organic chemical vapour deposition in the presence of colloidal gold particles as catalysts. Transmission electron microscopy and photoluminescence measurements were carried out to investigate the effects of V/III ratio and nanowire diameter on structural and optical properties. Results show that InP nanowires grow preferably in the wurtzite crystal structure than the zinc blende crystal structure with increasing V/III ratio or decreasing diameter. Additionally, time-resolved photoluminescence (TRPL) studies have revealed that wurtzite nanowires show longer recombination lifetimes of approximately 2500 ps with notably higher quantum efficiencies.

Effect of macroscopic vascular invasion (MVI), extrahepatic spread (EHS), and ECOG performance status (ECOG PS) on outcome in patients with advanced hepatocellular carcinoma (HCC) treated with sorafenib: Analysis of two phase III, randomized, double-blind trials

4580^

Background: The landmark phase III SHARP trial (Llovet et al, N Engl J Med, 2008) showed that sorafenib is effective and safe for the treatment of advanced HCC. These results were confirmed in an Asian population in the phase III Asia-Pacific (AP) study (Cheng et al, Lancet Oncol, 2009). We compared outcomes of sorafenib treatment in patients enrolled in the SHARP and AP trials with known baseline predictors of poor prognosis. Methods: Patients with advanced, unresectable, measurable HCC, ECOG PS 0–2, Child-Pugh A, and no prior systemic therapy for HCC were randomized to sorafenib 400 mg BID or placebo (SHARP: N=602; AP: N=226). Patients in the AP study had more evolved disease and a predominance of hepatitis B infection. Endpoints included overall survival (OS), disease-control rate (DCR; defined as complete/partial response or stable disease by RECIST, maintained for ≥28 days from first demonstration of response), and safety. Results: Efficacy results are shown in the table . The incidence of grade 3/4 drug-related adverse events (AEs) across subgroups in each study was consistent with the overall population for each study. The most common grade 3/4 AEs in all sorafenib populations were hand-foot skin reaction and diarrhea. Conclusions: Sorafenib is effective and safe for the treatment of advanced HCC in patients globally, irrespective of baseline ECOG PS and presence or absence of MVI and/or EHS.

[Table: see text]

[Table: see text]

ASCO Conflict of Interest Policy and Exceptions

In compliance with the guidelines established by the ASCO Conflict of Interest Policy (J Clin Oncol. 2006 Jan 20;24[3]:519–521) and the Accreditation Council for Continuing Medical Education (ACCME), ASCO strives to promote balance, independence, objectivity, and scientific rigor through disclosure of financial and other interests, and identification and management of potential conflicts. According to the ASCO Conflict of Interest Policy, the following financial and other relationships must be disclosed: employment or leadership position, consultant or advisory role, stock ownership, honoraria, research funding, expert testimony, and other remuneration (J Clin Oncol. 2006 Jan 20;24[3]:520). The ASCO Conflict of Interest Policy disclosure requirements apply to all authors who submit abstracts to the Annual Meeting.

For clinical trials that began accrual on or after April 29, 2004, ASCO's Policy places some restrictions on the financial relationships of principal investigators (J Clin Oncol. 2006 Jan 20;24[3]:521). If a principal investigator holds any restricted relationships, his or her abstract will be ineligible for placement in the 2009 Annual Meeting unless the ASCO Ethics Committee grants an exception. Among the circumstances that might justify an exception are that the principal investigator (1) is a widely acknowledged expert in a particular therapeutic area; (2) is the inventor of a unique technology or treatment being evaluated in the clinical trial; or (3) is involved in international clinical oncology research and has acted consistently with recognized international standards of ethics in the conduct of clinical research. NIH-sponsored trials are exempt from the Policy restrictions. Abstracts for which authors requested and have been granted an exception in accordance with ASCO's Policy are designated with a caret symbol (^) in the Annual Meeting Proceedings.

For more information about the ASCO Conflict of Interest Policy and the exceptions process, please visit www.asco.org/conflictofinterest .

Efficacy and safety of sorafenib in patients with advanced hepatocellular carcinoma (HCC): Asia-Pacific (AP) trial subgroup analyses by baseline transaminase (ALT/AST)/α-fetoprotein (AFP) levels

4590^

Background: Results of the phase III, randomized, double blind, placebo-controlled AP trial demonstrated that sorafenib is effective and safe for the treatment of advanced HCC in patients from the AP region (Cheng et al, Lancet Oncol, 2009). Hepatic function influences treatment as a measure of organ damage and tumor stage. We performed subset analyses of the AP study dataset according to baseline hepatic function, as indicated by levels of ALT/AST and AFP. Methods: Patients (N=226) with advanced HCC, ECOG PS 0–2, Child-Pugh class A, and no prior systemic therapy were randomized 2:1 to receive sorafenib 400 mg BID or placebo. Endpoints included overall survival (OS), disease-control rate (DCR; defined as complete/partial response or stable disease by RECIST, maintained for ≥28 days from first demonstration of response), time to progression (TTP) and safety. Patients were grouped by baseline levels of ALT/AST (normal, mild, or moderate) and AFP (normal or abnormal). Results: Median TTP, OS and DCR by subset are shown in the table . The most common grade 3/4 adverse events in the sorafenib populations were hand-foot skin reaction and diarrhea. Conclusions: Sorafenib was effective and safe in patients from the AP region with advanced HCC within a broad range of baseline hepatic enzyme and AFP levels. These results suggest that sorafenib is an effective treatment for HCC, irrespective of baseline ALT/AST or AFP levels.

[Table: see text]

[Table: see text]

ASCO Conflict of Interest Policy and Exceptions

In compliance with the guidelines established by the ASCO Conflict of Interest Policy (J Clin Oncol. 2006 Jan 20;24[3]:519–521) and the Accreditation Council for Continuing Medical Education (ACCME), ASCO strives to promote balance, independence, objectivity, and scientific rigor through disclosure of financial and other interests, and identification and management of potential conflicts. According to the ASCO Conflict of Interest Policy, the following financial and other relationships must be disclosed: employment or leadership position, consultant or advisory role, stock ownership, honoraria, research funding, expert testimony, and other remuneration (J Clin Oncol. 2006 Jan 20;24[3]:520). The ASCO Conflict of Interest Policy disclosure requirements apply to all authors who submit abstracts to the Annual Meeting.

For clinical trials that began accrual on or after April 29, 2004, ASCO's Policy places some restrictions on the financial relationships of principal investigators (J Clin Oncol. 2006 Jan 20;24[3]:521). If a principal investigator holds any restricted relationships, his or her abstract will be ineligible for placement in the 2009 Annual Meeting unless the ASCO Ethics Committee grants an exception. Among the circumstances that might justify an exception are that the principal investigator (1) is a widely acknowledged expert in a particular therapeutic area; (2) is the inventor of a unique technology or treatment being evaluated in the clinical trial; or (3) is involved in international clinical oncology research and has acted consistently with recognized international standards of ethics in the conduct of clinical research. NIH-sponsored trials are exempt from the Policy restrictions. Abstracts for which authors requested and have been granted an exception in accordance with ASCO's Policy are designated with a caret symbol (^) in the Annual Meeting Proceedings.

For more information about the ASCO Conflict of Interest Policy and the exceptions process, please visit www.asco.org/conflictofinterest .

Impact of prior surgical resection with curative intent on the efficacy and safety of sorafenib in patients with advanced hepatocellular carcinoma (HCC): Subset analysis of the Asia-Pacific (AP) study

e15518^

Background: The multinational, phase III, randomized, double-blind, placebo-controlled AP study demonstrated that sorafenib is effective and safe for the treatment of advanced HCC in patients from the AP region (Cheng, et al. Lancet Oncol, 2009). Surgical resection with curative intent is a commonly used procedure for the treatment of HCC; however, tumor recurrence occurs in the majority of patients. Hence, it is of interest to analyze the efficacy and safety of sorafenib in patients who had undergone prior partial hepatectomy. Methods: Patients (N=226) with advanced HCC, ECOG PS 0–2, Child-Pugh class A, and no prior systemic therapy were randomized 2:1 to receive either sorafenib 400 mg BID or placebo. End points included overall survival (OS), disease-control rate (DCR; defined as complete/partial response or stable disease by RECIST, maintained for ≥28 d from first demonstration of response), time-to-progression (TTP), and safety. Results: Of 226 patients enrolled, 70 had previously undergone partial hepatectomy. Median TTP, OS, and DCR by subset are shown in the table. The safety profile of sorafenib in patients with and without prior hepatectomy was similar to that reported for the total study population. The most common grade 3/4 adverse events in the sorafenib groups were hand-foot skin reaction and diarrhea. Conclusions: Sorafenib was safe for the treatment of advanced HCC in patients from the AP region, whether or not they had undergone prior surgical resection. Sorafenib treatment resulted in similar TTP in patients with and without a history of prior partial hepatectomy, and the magnitude of TTP was similar in both groups to that in the overall population. Due to small sample size, further study is warranted. [Table: see text]

[Table: see text]

ASCO Conflict of Interest Policy and Exceptions

In compliance with the guidelines established by the ASCO Conflict of Interest Policy (J Clin Oncol. 2006 Jan 20;24[3]:519–521) and the Accreditation Council for Continuing Medical Education (ACCME), ASCO strives to promote balance, independence, objectivity, and scientific rigor through disclosure of financial and other interests, and identification and management of potential conflicts. According to the ASCO Conflict of Interest Policy, the following financial and other relationships must be disclosed: employment or leadership position, consultant or advisory role, stock ownership, honoraria, research funding, expert testimony, and other remuneration (J Clin Oncol. 2006 Jan 20;24[3]:520). The ASCO Conflict of Interest Policy disclosure requirements apply to all authors who submit abstracts to the Annual Meeting.

For clinical trials that began accrual on or after April 29, 2004, ASCO's Policy places some restrictions on the financial relationships of principal investigators (J Clin Oncol. 2006 Jan 20;24[3]:521). If a principal investigator holds any restricted relationships, his or her abstract will be ineligible for placement in the 2009 Annual Meeting unless the ASCO Ethics Committee grants an exception. Among the circumstances that might justify an exception are that the principal investigator (1) is a widely acknowledged expert in a particular therapeutic area; (2) is the inventor of a unique technology or treatment being evaluated in the clinical trial; or (3) is involved in international clinical oncology research and has acted consistently with recognized international standards of ethics in the conduct of clinical research. NIH-sponsored trials are exempt from the Policy restrictions. Abstracts for which authors requested and have been granted an exception in accordance with ASCO's Policy are designated with a caret symbol (^) in the Annual Meeting Proceedings.

For more information about the ASCO Conflict of Interest Policy and the exceptions process, please visit www.asco.org/conflictofinterest .