Color-tunable stable quasi-2D hybrid metal halide perovskites: synthesis, characterization, and optical analysis

Metal halide perovskites show remarkable optical properties and useful applications in optoelectronic devices. However, the instability of three-dimensional (3D) metal halide perovskites limits their applications, leading to the emergence of more stable two-dimensional (2D) metal halide perovskites. Herein, we present a facile synthesis of the 2D hybrid metal halide perovskite (EDA)(MA)n-1PbnBr3n+1 (EDA: ethylene diammonium, MA: methylammonium), where n = 1-6, and MAPbBr3 perovskite layers using an anti-solvent co-precipitation technique. The synthesized materials exhibited tunable optical properties, and the color emissions of pure EDAPbBr4 and (EDA)(MA)2Pb3Br10 perovskites were successfully tailored by altering halide anion layers. The band gap decreases as the value of n in the (EDA)(MA)n-1PbnBr3n+1 compound increases from 1 to 6. The as-prepared materials were characterized using X-ray diffraction (XRD) technique, Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-Vis), photoluminescence spectroscopy (PL), scanning electron microscopy (SEM), and energy dispersive X-ray analysis (EDX). Finally, the stability of the 2D hybrid metal halide perovskite structures was evaluated under ambient conditions over different periods. Their tunable color emission was investigated and robust fluorescence was observed after 55 days. Thus, this study provides valuable insights into the synthesis and characterization of 2D hybrid metal halide perovskites for tunable color emission, highlighting their potential for use in various optoelectronic applications.

Engineering of nickel, cobalt oxides and nickel/cobalt binary oxides by electrodeposition and application as binder free electrodes in supercapacitors

Cobalt oxide, nickel oxide and cobalt/nickel binary oxides were synthesised by electrodeposition. To fine tune composition of CoNi alloys, growth parameters including voltage, electrolyte pH/concentration and deposition time were varied. These produced nanomaterials were used as binder free electrodes in supercapacitor cells and tested using three electrode setup in 2 MKOH aqueous electrolyte. Cyclic voltammetry and galvanostatic charge/discharge were used at different scan rates (5-100 mV/s) and current densities (1-10 A/g) respectively to investigate the capacitive behaviour and measure the capacitance of active material. Electrochemical impedance spectroscopy was used to analyse the resistive/conductive behaviours of these electrodes in frequency range of 100 kHz to 0.01 Hz at applied voltage of 10 mV. Binary oxide electrode displayed superior electrochemical performance with the specific capacitance of 176 F/g at current density of 1 A/g. This hybrid electrode also displayed capacitance retention of over 83% after 5000 charge/discharge cycles. Cell displayed low solution resistance of 0.35 Ω along with good conductivity. The proposed facile approach to synthesise binder free blended metal electrodes can result in enhanced redox activity of pseudocapacitive materials. Consequently, fine tuning of these materials by controlling the cobalt and nickel contents can assist in broadening their applications in electrochemical energy storage in general and in supercapacitors in particular.

From multi-segmented to core/shell nanorods: morphology evolution in Fe-Au nanorods by tuning fabrication conditions

Aiming to obtain hybrid magneto-plasmonic nanostructures, we have developed multisegmented and core/shell structured Fe-Au nanorods using template assisted electrochemical deposition. A facile method of tuning the growth pattern of multisegmented nanorods into core/shell structured is demonstrated. With a precise control of current density and deposition time, a brick-stacked wire like growth led to the formation of hollow nanotubes that could be further tuned to multilayered hollow nanotubes and core/shell structured nanorods. TEM imaging and STEM-EELS technique were used to explore the morphology, microstructure and the distribution of Au and Fe in the nanorods. The easy magnetization direction was found to be perpendicular to the nanorods' growth direction in the segmented nanorods. On the other hand, core/shell nanorods exhibited isotropic behavior. Our findings provide deeper insights into the fabrication of hybrid nanorods and the opportunity to tune the fabrication method to vary their morphology accordingly. Such studies will benefit design of hybrid nanorods with specific morphologies and physical properties and hence their integration into sensing, spintronics and other potential biomedical and technological applications.

Tuning Easy Magnetization Direction and Magnetostatic Interactions in High Aspect Ratio Nanowires

Cobalt nanowires have been synthesized by electrochemical deposition using track-etched anodized aluminum oxide (AAO) templates. Nanowires with varying spacing-to-diameter ratios were prepared, and their magnetic properties were investigated. It is found that the nanowires’ easy magnetization direction switches from parallel to perpendicular to the nanowire growth direction when the nanowire’s spacing-to-diameter ratio is reduced below 0.7, or when the nanowires’ packing density is increased above 5%. Upon further reduction in the spacing-to-diameter ratio, nanowires’ magnetic properties exhibit an isotropic behavior. Apart from shape anisotropy, strong dipolar interactions among nanowires facilitate additional uniaxial anisotropy, favoring an easy magnetization direction perpendicular to their growth direction. The magnetic interactions among the nanowires were studied using the standard method of remanence curves. The demagnetization curves and Delta m (Δm) plots showed that the nanowires interact via dipolar interactions that act as an additional uniaxial anisotropy favoring an easy magnetization direction perpendicular to the nanowire growth direction. The broadening of the dipolar component of Δm plots indicate an increase in the switching field distribution with the increase in the nanowires’ diameter. Our findings provide an important insight into the magnetic behavior of cobalt nanowires, meaning that it is crucial to design them according to the specific requirements for the application purposes.

Facile Organometallic Synthesis of Fe-Based Nanomaterials by Hot Injection Reaction

Fe-based colloids with a core/shell structure consisting of metallic iron and iron oxide were synthesized by a facile hot injection reaction of iron pentacarbonyl in a multi-surfactant mixture. The size of the colloidal particles was affected by the reaction temperature and the results demonstrated that their stability against complete oxidation related to their size. The crystal structure and the morphology were identified by powder X-ray diffraction and transmission electron microscopy, while the magnetic properties were studied at room temperature with a vibrating sample magnetometer. The injection temperature plays a very crucial role and higher temperatures enhance the stability and the resistance against oxidation. For the case of injection at 315 °C, the nanoparticles had around a 10 nm mean diameter and revealed 132 emu/g. Remarkably, a stable dispersion was created due to the colloids' surface functionalization in a nonpolar solvent.

Chemically synthesized nanoparticles of iron and iron-carbides

In this paper, we report a one-pot chemical synthesis technique for the preparation of iron and iron-carbide nanoparticles. Mössbauer spectroscopy, X-ray diffraction and magnetometry were used as the main tools to identify the different phases of Fe–C present. The influence of experimental parameters on the structural and compositional properties of nanoparticles was investigated in detail. These particles show ferromagnetic behavior with room temperature coercivity higher than 300 Oe. The X-ray diffraction was complemented by Mössbauer spectroscopy and thermo-magnetic analysis. Remarkably, the carbon content in iron-carbide nanoparticles (carbon rich or carbon poor iron-carbides) can be modulated simply by varying the experimental conditions, like the reaction time, temperature and iron precursor concentration. Magnetic properties can be tailored based upon crystallographic structure and particles composition.

In this paper, we report a one-pot chemical synthesis for the preparation of iron and iron-carbide nanoparticles.

Evaluating blood clot progression using magnetic particle spectroscopy

PURPOSE

To evaluate the thrombus maturity noninvasively providing the promise of much earlier and more accurate diagnosis of diseases ranging from stroke to myocardial infarction to deep vein thrombosis.

METHODS

Magnetic spectroscopy of nanoparticle Brownian rotation (MSB), a form of magnetic particle spectroscopy sensitive to Brownian rotation of magnetic nanoparticles, was used for the detection and characterization of blood clots. The nanoparticles' relaxation time was quantified by scaling the MSB spectra in frequency to match the spectra from nanoparticles in a reference state. The nanoparticles' relaxation time, in the bound state, was used to characterize the nanoparticle binding to thrombin on the blood clot. The number of nanoparticles bound to the clot was also estimated. Both the relaxation time and the weight of bound nanoparticles were obtained for clots of several ages, reflecting different stages of development and organization. The impact of clot development was explored using functionalized nanoparticles present during clot formation.

RESULTS

The relaxation time of the bound nanoparticles decreases for more mature, organized clots. The number of nanoparticles able to bind the clot diminishes quantitatively with clot age. On mature clots, the nanoparticles bind the thrombin on the surface while for developing clots the nanoparticles bind several thrombin molecules or become trapped in the clot matrix during formation.

CONCLUSIONS

By estimating the magnetic nanoparticles' relaxation time the clot age and organization can be predicted. The purposed methods are quick and minimally invasive for in vivo applications.

Blood clot detection using magnetic nanoparticles

Deep vein thrombosis, the development of blood clots in the peripheral veins, is a very serious, life threatening condition that is prevalent in the elderly. To deliver proper treatment that enhances the survival rate, it is very important to detect thrombi early and at the point of care. We explored the ability of magnetic particle spectroscopy (MSB) to detect thrombus via specific binding of aptamer functionalized magnetic nanoparticles with the blood clot. MSB uses the harmonics produced by nanoparticles in an alternating magnetic field to measure the rotational freedom and, therefore, the bound state of the nanoparticles. The nanoparticles' relaxation time for Brownian rotation increases when bound [A.M. Rauwerdink and J. B. Weaver, Appl. Phys. Lett. 96, 1 (2010)]. The relaxation time can therefore be used to characterize the nanoparticle binding to thrombin in the blood clot. For longer relaxation times, the approach to saturation is more gradual reducing the higher harmonics and the harmonic ratio. The harmonic ratios of nanoparticles conjugated with anti-thrombin aptamers (ATP) decrease significantly over time with blood clot present in the sample medium, compared with nanoparticles without ATP. Moreover, the blood clot removed from the sample medium produced a significant MSB signal, indicating the nanoparticles are immobilized on the clot. Our results show that MSB could be a very useful non-invasive, quick tool to detect blood clots at the point of care so proper treatment can be used to reduce the risks inherent in deep vein thrombosis.

Sensitivity Limits for in vivo ELISA Measurements of Molecular Biomarker Concentrations

The extremely high sensitivity that has been suggested for magnetic particle imaging has its roots in the unique signal produced by the nanoparticles at the frequencies of the harmonics of the drive field. That sensitivity should be translatable to other methods that utilize magnetic nanoparticle probes, specifically towards magnetic nanoparticle spectroscopy that is used to measure molecular biomarker concentrations for an “in vivo ELISA” assay approach. In this paper, we translate the predicted sensitivity of magnetic particle imaging into a projected sensitivity limit for in vivo ELISA. The simplifying assumptions adopted are: 1) the limiting noise in the detection system is equivalent to the minimum detectable mass of nanoparticles; 2) the nanoparticle’s signal arising from Brownian relaxation is completely eliminated by the molecular binding event, which can be accomplished by binding the nanoparticle to something so massive that it can no longer physically rotate and is large enough that Neel relaxation is minimal. Given these assumptions, the equation for the minimum concentration of molecular biomarker we should be able to detect is obtained and the in vivo sensitivity is estimated to be in the attomolar to zeptomolar range. Spectrometer design and nonspecific binding are the technical limitations that need to be overcome to achieve the theoretical limit presented.

Exchange Bias Effects in Iron Oxide-Based Nanoparticle Systems

The exploration of exchange bias (EB) on the nanoscale provides a novel approach to improving the anisotropic properties of magnetic nanoparticles for prospective applications in nanospintronics and nanomedicine. However, the physical origin of EB is not fully understood. Recent advances in chemical synthesis provide a unique opportunity to explore EB in a variety of iron oxide-based nanostructures ranging from core/shell to hollow and hybrid composite nanoparticles. Experimental and atomistic Monte Carlo studies have shed light on the roles of interface and surface spins in these nanosystems. This review paper aims to provide a thorough understanding of the EB and related phenomena in iron oxide-based nanoparticle systems, knowledge of which is essential to tune the anisotropic magnetic properties of exchange-coupled nanoparticle systems for potential applications.

Core/shell iron/iron oxide nanoparticles: are they promising for magnetic hyperthermia?

Core/shell iron/iron oxide nanoparticles are promising for magnetic hyperthermia provided their size is big enough (>14 nm) in order to minimize surface disorder and hollowing effects that seriously deteriorate their heating efficiency.

From core/shell to hollow Fe/γ-Fe₂O₃ nanoparticles: evolution of the magnetic behavior

High quality Fe/γ-Fe2O3 core/shell, core/void/shell, and hollow nanoparticles with two different sizes of 8 and 12 nm were synthesized, and the effect of morphology, surface and finite-size effects on their magnetic properties including the exchange bias (EB) effect were systematically investigated. We find a general trend for both systems that as the morphology changes from core/shell to core/void/shell, the magnetization of the system decays and inter-particle interactions become weaker, while the effective anisotropy and the EB effect increase. The changes are more drastic when the nanoparticles become completely hollow. Noticeably, the morphological change from core/shell to hollow increases the mean blocking temperature for the 12 nm particles but decreases for the 8 nm particles. The low-temperature magnetic behavior of the 12 nm particles changes from a collective super-spin-glass system mediated by dipolar interactions for the core/shell nanoparticles to a frustrated cluster glass-like state for the shell nanograins in the hollow morphology. On the other hand for the 8 nm nanoparticles core/shell and hollow particles the magnetic behavior is more similar, and a conventional spin glass-like transition is obtained at low temperatures. In the case of the hollow nanoparticles, the coupling between the inner and outer spin layers in the shell gives rise to an enhanced EB effect, which increases with increasing shell thickness. This indicates that the morphology of the shell plays a crucial role in this kind of exchange-biased systems.

Genetic divergence for high-molecular weight glutenin subunits (HMW-GS) in indigenous landraces and commercial cultivars of bread wheat of Pakistan

Wheat flour quality is an important consideration in the breeding and development of new cultivars. A strong association between high-molecular weight glutenin subunits (HMW-GS) and bread making quality has resulted in the widespread utilization of HMW-GS in wheat breeding. In this study, we analyzed 242 lines of wheat, including landraces from the provinces of Punjab and Baluchistan, as well as the commercial varieties of Pakistan, to determine allelic variation in the Glu-A1, Glu-B1, and Glu-D1 loci encoding HMW-GS. Higher genetic diversity was observed for HMW-GS in landraces from Baluchistan, followed by landraces collected from Punjab and then commercial varieties. Rare and uncommon subunits were observed in Glu-B1, whereas Glu-A1 was less polymorphic. However, Glu-B1 was the highest contributor to overall diversity (78%), with a total of 31 rare alleles, followed by Glu-D1 (20%) with the high quality 5+10 allele and other variants. Commercial cultivars possessed favorable alleles, potentially from indirect selection for wheat flour quality by the breeders; however, this indirect selection has decreased the pedigree base of commercial cultivars. The allelic combinations, including 2*, 5+10, and 17+18, showing high quality scores were frequent among landraces, indicating their usefulness in future crop improvement and breeding programs.

Enhanced magnetism in highly ordered magnetite nanoparticle-filled nanohole arrays

A new approach to develop highly ordered magnetite (Fe3O4) nanoparticle-patterned nanohole arrays with desirable magnetic properties for a variety of technological applications is presented. In this work, the sub-100 nm nanohole arrays are successfully fabricated from a pre-ceramic polymer mold using spin-on nanoprinting (SNAP). These nanoholes a then filled with monodispersed, spherical Fe3O4 nanoparticles of about 10 nm diameter using a novel magnetic drag and drop procedure. The nanohole arrays filled with magnetic nanoparticles a imaged using magnetic force microscopy (MFM). Magnetometry and MFM measurements reveal room temperature ferromagnetism in the Fe3O4-filled nanohole arrays, while the as-synthesized Fe3O4 nanoparticles exhibit superparamagnetic behavior. As revealed by MFM measurements, the enhanced magnetism in the Fe3O4-filled nanohole arrays originates mainly from the enhanced magnetic dipole interactions of Fe3 O4 nanoparticles within the nanoholes and between adjacent nanoholes. Nanoparticle filled nanohole arrays can be highly beneficial in magnetic data storage and other applications such as microwave devices and biosensor arrays that require tunable and anisotropic magnetic properties.

Magnetic entropy change in core/shell and hollow nanoparticles

The development of positive magnetic entropy change in the case of ferromagnetic (FM) nanostructures is a rare occurrence. We observe positive magnetic entropy change in core/shell (Fe/γ-Fe2O3) and hollow (γ-Fe2O3) nanoparticles and its origin is attributed to a disordered state in the nanoparticles due to the random distribution of anisotropy axes which inhibits any long range FM ordering. The effect of the energy barrier distribution on the magnetic entropy change and its impact on the universal behavior based on rescaled entropy change curves for core/shell and hollow nanostructures is discussed. Our study emphasizes that the magnetic entropy change is an excellent parameter to study temperature and field dependent magnetic freezing in such complex nanostructures.

Mechanism and controlled growth of shape and size variant core/shell FeO/Fe3O4 nanoparticles

We report a novel synthesis approach for the growth of core/shell FeO/Fe3O4 nanoparticles with controlled shape and size. FeO particles were partially oxidized to form core/shell FeO/Fe3O4 structures, as evidenced from transmission electron microscopy, X-ray diffraction, and magnetometry analysis. We find that the molar ratios and concentrations of surfactants are the key parameters in controlling the particle size. The particles can grow in either isotropic or anisotropic shapes, depending upon a chemical reaction scheme that is controlled kinetically or thermodynamically. The competitive growth rates of {111} and {100} facets can be used to tune the final shape of nanoparticles to spherical, cubic, octahedral, octopod, and cuboctahedral geometries. FeO particles can also be oxidized chemically or thermally to form Fe3O4 nanoparticles. By following the same synthesis technique, it is possible to synthesize rods and triangles of Fe3O4 by introducing twinnings and defects into the crystal structure of the seed. The thermally activated first-order Verwey transition at ~120 K has been observed in all the synthesized FeO/Fe3O4 nanoparticles, indicating its independence from the particle shape. These core/shell nanoparticles exhibit a strong shift in field-cooled hysteresis loops accompanied by an increase in coercivity (the so-called exchange bias effect), but the low field-switching behavior appears to vary with the particle shape.

Chemically synthesized hollow nanostructures in iron oxides

In this work, we report a detailed study of the formation of hollow nanostructures in iron oxides. Core/shell Fe/Fe-oxide nanoparticles were synthesized by thermal decomposition of Fe(CO)(5) at high temperature. It was found that 8 nm is the critical size above which the particles have a core/shell morphology, whereas below this size the particles exhibit a hollow morphology. Annealing the core/shell particles under air also leads to the formation of hollow spheres with a significant increase in the average particle size. In the case of the thermally activated Kirkendall process, the particles do not fully transform into hollow structures but many irregular shaped voids exist inside each particle. The 8 nm hollow particles are superparamagnetic at room temperature with a blocking temperature of 70 K whereas the core/shell particles are ferromagnetic.

A phase II Brown University Oncology Group study of docetaxel, oxaliplatin, and capecitabine (DOC) for metastatic esophagogastric cancer

e15541^

Background: We previously reported results of a phase I study of oxaliplatin, docetaxel, and capecitabine for advanced esophagogastric cancer (Evans et al, Am J C Onc 2007). In this phase II component we describe response rates, toxicity, and survival data. Methods: Patients with histologically confirmed metastatic esophagogastric squamous or adenocarcinoma were eligible. Patients received oxaliplatin 50mg/m2 and docetaxel 35mg/m2 on days 1 and 8 as well as capecitabine 750 mg/m2 twice daily on days 1–10 in each 21 day cycle. Results: 21 patients were enrolled and were evaluable. Median age was 65, range 46–83. All had adenocarcinoma histology. Three patients received prior adjuvant or neoadjuvant therapy. A total of 91 cycles were delivered, median of 4, range of 1–11. Median follow-up was 2 years; all patients have been followed for at least 1 year. Median overall survival was 11 months. The overall response rate was 43%. Three patients achieved a complete response. Two of these patients remain without evidence of disease at 38 and 12 months. Three patients experienced confirmed pulmonary emboli, and one patient expired at home with possible pulmonary embolism (exact cause unknown).Other Grade 3/4 toxicities were: nausea (3/21), fatigue (2/21), diarrhea (4/21), hand/foot (1/21), dehydration (3/21), esophagitis (2/21), infection (1/21), Electrolyte (3/21), neutropenic fever (2/21), neutropenia (4/21), anemia (1/21). Conclusions: DOC is an active and easily administered regimen for metastatic esophagogastric cancer. Consideration should be given for prophylactic anticoagulation for patients with metastatic esophagogastric cancer.

[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 .

Neoadjuvant bevacizumab, oxaliplatin, 5-fluorouracil, and radiation in clinical stage II-III rectal cancer

4105^

Background: This study evaluates induction bevacizumab and FOLFOX followed by concurrent chemoradiotherapy (CRT) with bevacizumab, weekly oxaliplatin, and continuous infusion 5-FU prior to surgical resection of newly-diagnosed Stage II or III rectal cancer. Methods: Eligible patients received one month of induction, biweekly bevacizumab (5mg/kg) and modified FOLFOX6. Patients then received 50.4Gy of radiation and concurrent bevacizumab (5 mg/kg on days 1, 15, and 29), oxaliplatin (50 mg/m2/week for 6 weeks), and 5-FU (200mg/m2/day) as a continuous IV infusion throughout radiation. Due to gastrointestinal toxicity, the oxaliplatin dose was reduced to 40 mg/m2/week. Resection was performed 4 to 8 weeks after the completion of CRT. Adjuvant chemotherapy was started after 4 but less than 12 weeks following surgical resection and consisted of 6 biweekly treatments of modified FOLFOX6 and bevacizumab. Results: Twenty-six eligible patients were treated. The median age was 50. One patient developed a grade 4 arrhythmia during induction chemotherapy and was removed from the study. Of the remaining 25 patients, there were no other grade 3 or 4 toxicities during induction FOLFOX/bevacizumab. Toxicity was more significant during chemoradiation. Any grade 3 toxicity was experienced by 19 of 25 (76%) patients. Grade 3 toxicities included diarrhea (40%), neutropenia (16%), pain (16%), fatigue (8%), nausea (8%), and radiation dermatitis (8%) and bleeding with menstruation (4%). Grade 4 toxicities included neutropenia (4%), sepsis (4%) and nausea/diarrhea (4%). Six of 25 resected patients (24%) had a complete pathologic response. Eight of 25 patients (32%) developed post-operative wound complications including infection/abscess (n=4), fistula (n=2), ischemic colonic reservoir (n=1) and sterile fluid collection (n=1). Nine of 25 (36%) patients developed postoperative wound complications including infection (n=4), delayed healing (n=3), leak/abscess (n=2), sterile fluid collection (n=2), ischemic colonic reservoir (n=1), and fistula (n=1). Conclusions: Concurrent oxaliplatin, bevacizumab, continuous infusion 5-FU and radiation causes significant gastrointestinal toxicity. The pathologic complete response rate of this regimen to similar to other fluorouracil based chemoradiaton regimens. The high incidence of post-operative wound complications is concerning and consistent with other reports utilizing bevacizumab prior to major surgical resections.

[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 .

Induction cetuximab (C) followed by C, paclitaxel (P), carboplatin (CP) and concurrent radiation (RT) for locoregionally advanced squamous cell carcinoma of the head and neck (SCCHN)

16504

Background: C is an IgG1 chimerized, monoclonal antibody that binds specifically to the epidermal growth factor receptor, which is expressed in 90–100% of HNC. We conducted a phase II study to evaluate the toxicity and efficacy of induction C followed by concurrent C with chemoRT for patients (pts) with SCCHN. Methods: Eligible pts had untreated stage III or IV, SCCHN. All pts received induction, single agent, C, 400 mg/m2 week 1, followed by 250 mg/m2 weeks 2, 3, and 4. Potentially operable pts then received C, 250 mg/m2, P 40 mg/m2 and CP AUC=1, weekly x 5 wks, with 45 Gy RT then underwent endoscopic biopsy. If the biopsy was negative, pts received 3 additional weekly doses of C, P, CP and 22–27 Gy boost RT. Inoperable pts received 8 weeks of C, P and CP and 66.6–72 Gy RT. All pts then received maintenance C 250 mg/m2/week x 24 weeks. Results: 29 pts have been enrolled. Male:Female 18:11. Median age = 55 (38–75). Primary sites included oral cavity (10 pts), oropharynx (1), larynx (12), hypopharynx (2), and glottis (4). The tumor stages were III (10 pts), IV (19). Toxicity data are available for 23 pts. 2 of 23 (9%) had grade (G) 4 toxicities (hypokalemia =1, ischemic colitis=1) however there were no treatment related deaths. G 2 toxicities included rash (52%), dysphagia (35%), mucositis (43.5%) and hypomagnesemia (9%). G 3 toxicities included rash (9%), dysphagia (44%), mucositis (26%) and XRT dermatitis (18%). Induction C responses by RECIST criteria were SD (14 pts) 61%, PR (7) 30%, and CR (1) 4%. Conclusion: C can be safely administered with chemoRT (CRT) for pts with HNC. C increases cutaneous toxicity but does not increase in-field CRT side effects. There were no unexpected high-grade adverse events. Preliminary single agent activity of C in untreated SCCHN is promising.

No significant financial relationships to disclose.

Shunt nephritis from Propionibacterium acnes in a solitary kidney

Since its initial description in 1965, immune complex glomerulonephritis associated with ventriculoatrial shunts (VAS) has been reported widely in the literature. The most common incriminating organism is Staphylococcus epidermidis, but less often, an organism generally regarded as nonpathogenic, such as Propionibacterium acnes, has been noted as the cause. Shunt infection usually occurs within a few months after placement or manipulation of the shunt, and shunt nephritis (SN) develops gradually over months to years after. Treatment involves mandatory removal of the shunt and antibiotics; prognosis is variable. We report a case of SN with P acnes that is unusual because of its occurrence in a solitary kidney 6 years after shunt placement, persistently negative blood cultures, and normal complement levels. Percutaneous biopsy of a solitary kidney should be considered if it is expected that the result may guide therapy of progressive renal failure.