Evaluating the efficacy of vaginal dehydroepiandosterone for vaginal symptoms in postmenopausal cancer survivors: NCCTG N10C1 (Alliance).

BACKGROUND: Women with estrogen deficiencies can suffer from vaginal symptoms that negatively impact sexual health. This study evaluated vaginal dehydroepiandrosterone (DHEA) for alleviation of vaginal symptoms. METHODS: This three-arm randomized, controlled trial evaluated DHEA 3.25 mg and DHEA 6.5 mg, each compared to a plain moisturizer (PM) over 12 weeks, to improve the severity of vaginal dryness or dyspareunia, measured with an ordinal scale, and overall sexual health using the Female Sexual Function Index (FSFI). Postmenopausal women with a history of breast or gynecologic cancer who had completed primary treatment, had no evidence of disease, and reported at least moderate vaginal symptoms were eligible. The mean change from baseline to week 12 in the severity of vaginal dryness or dyspareunia for each DHEA dose was compared to PM and analyzed by two independent t tests using a Bonferroni correction. RESULTS: Four hundred sixty-four women were randomized. All arms reported improvement in either dryness or dyspareunia. Neither DHEA dose was statistically significantly different from PM at 12 weeks (6.25 mg, p = .08; 3.25 mg, p = 0.48), although a significant difference at 8 weeks for 6.5 mg DHEA was observed (p = 0.005). Women on the 6.5 mg arm of DHEA reported significantly better sexual health on the FSFI (p < 0.001). There were no significant differences in provider-graded toxicities and few significant differences in self-reported side effects. CONCLUSION: PM and DHEA improved vaginal symptoms at 12 weeks. However, vaginal DHEA, 6.5 mg, significantly improved sexual health. Vaginal DHEA warrants further investigation in women with a history of cancer.

Continuous flow enzyme-catalyzed polymerization in a microreactor.

Enzymes immobilized on solid supports are increasingly used for greener, more sustainable chemical transformation processes. Here, we used microreactors to study enzyme-catalyzed ring-opening polymerization of ε-caprolactone to polycaprolactone. A novel microreactor design enabled us to perform these heterogeneous reactions in continuous mode, in organic media, and at elevated temperatures. Using microreactors, we achieved faster polymerization and higher molecular mass compared to using batch reactors. While this study focused on polymerization reactions, it is evident that similar microreactor based platforms can readily be extended to other enzyme-based systems, for example, high-throughput screening of new enzymes and to precision measurements of new processes where continuous flow mode is preferred. This is the first reported demonstration of a solid supported enzyme-catalyzed polymerization reaction in continuous mode.

Methodology for detecting residual phosphoric acid in polybenzoxazole fibers.

Because of the premature failure of in-service soft-body armor containing the ballistic fiber poly[(benzo-[1,2-d:5,4-d']-benzoxazole-2,6-diyl)-1,4-phenylene] (PBO), the Office of Law Enforcement Standards (OLES) at the National Institute of Standards and Technology (NIST) initiated a research program to investigate the reasons for this failure and to develop testing methodologies and protocols to ensure that these types of failures do not reoccur. In a report that focused on the stability of the benzoxazole ring that is characteristic of PBO fibers, Holmes, G. A.; Rice, K.; Snyder, C. R. J. Mater. Sci. 2006, 41, 4105-4116, showed that the benzoxazole ring was susceptible to hydrolytic degradation under acid conditions. Because of the processing conditions for the fibers, it is suspected by many researchers that residual phosphoric acid may cause degradation of the benzoxazole ring resulting in a reduction of ballistic performance. Prior to this work, no definitive data have indicated the presence of phosphoric acid since the residual phosphorus is not easily extracted and the processed fibers are known to incorporate phosphorus containing processing aids. Methods to efficiently extract phosphorus from PBO are described in this article. Further, characterization determined that the majority of the extractable phosphorus in PBO was attributed to the octyldecyl phosphate processing aid with some phosphoric acid being detected. Analysis by matrix assisted laser desorption ionization of model PBO oligomers indicates that the nonextractable phosphorus is attached to the PBO polymer chain as a monoaryl phosphate ester. The response of model aryl phosphates to NaOH exposure indicates that monoaryl phosphate ester is stable to NaOH washes used in the manufacturing process to neutralize the phosphoric acid reaction medium and to extract residual phosphorus impurities.

Synthesis of Polymerizable Cyclodextrin Derivatives for Use in Adhesion-Promoting Monomer Formulations.

The synthesis of the cyclodextrin derivatives reported herein was assisted by extensive literature research together with structure-property relationships derived from three-dimensional molecular modeling. These studies led to the hypothesis that many of the 21 hydroxyl groups on beta-cyclodextrin molecules could be derivatized to form a closely related family of analogous chemical compounds containing both polymerizable groups and hydrophilic ionizable ligand (substrate-binding) groups, each attached via hydrolytically-stable ether-linkages. The vinylbenzylether polymerizable groups should readily homopolymerize and also copolymerize with methacrylates. This could be highly useful for dental applications because substantially all contemporary dental resins and composites are based on methacrylate monomers. Due to hydrophilic ligands and residual hydroxyl groups, these cyclodextrin derivatives should penetrate hydrated layers of dentin and enamel to interact with collagen and tooth mineral. Analyses indicated that the diverse reaction products resulting from the method of synthesis reported herein should comprise a family of copolymerizable molecules that collectively contain about 30 different combinations of vinylbenzyl and hexanoate groups on the various molecules, with up to approximately seven of such groups combined on some of the molecules. Although the hypothesis was supported, and adhesive bonding to dentin is expected to be significantly improved by the use of these polymerizable cyclodextrin derivatives, other efforts are planned for improved synthetic methods to ensure that each of the reaction-product molecules will contain at least one copolymerizable moiety. The long-term objective is to enable stronger and more durable attachments of densely cross-linked polymers to hydrated hydrophilic substrates. Capabilities for bonding of hydrolytically stable polymers to dental and perhaps other hydrous biological tissues could provide widespread benefits.

Randomized comparison of a nicotine inhaler and bupropion for smoking cessation and relapse prevention.

OBJECTIVE: To compare the combination of a nicotine inhaler and bupropion to either treatment alone for initiating smoking abstinence and relapse prevention. METHODS: Smokers were randomized to receive a nicotine inhaler, bupropion, or both for 3 months. At 3 months, smoking-abstinent study participants were randomized to their initial medications or placebo. Participants who were smoking at 3 months were randomized to an alternative treatment regimen or placebo. This study was conducted from July 2001 to January 2003. RESULTS: A total of 1700 smokers were randomized to treatment (phase 1) for 3 months. Among the 941 study participants eligible for randomization to the phase 2 trial, 837 continued in the study. For the phase 2 trial, 405 smoking-abstinent participants were randomized to relapse prevention for 9 additional months, and 432 smokers were randomized to re-treatment for an additional 3 months. At the end of the initial 3 months of treatment (phase 1), 82 (14%) of 566, 145 (26%) of 567, and 194 (34%) of 567 study participants receiving a nicotine inhaler, bupropion, or both, respectively, were abstinent from smoking. Of the 405 smoking-abstinent participants at the end of 3 months, the bupropion group had more smokers than the placebo group (mean No. of smokers, 1.5 vs 1.1; P < .001), and the nicotine inhaler group had higher smoking abstinence rates at 12 months than the placebo group. Those receiving combination therapy had reduced rates of relapse to smoking for the first 3 months of relapse prevention, but this difference disappeared after the initial 3 months. Of the 432 study participants who were smoking at the end of 3 months and who received an alternative treatment regimen, the 223 smokers initially assigned to a nicotine inhaler were more likely to stop smoking at 6 months if they were re-treated with bupropion instead of placebo (8 [7%] of 111 vs 0 [0%] of 112; P = .003), and the 209 smokers initially treated with bupropion and re-treated with a nicotine inhaler did not have significantly higher smoking abstinence rates (6 [6%] of 104 vs 3 [3%] of 105; P = -.50). CONCLUSION: Combined therapy with a nicotine inhaler and bupropion increased smoking abstinence rates. Continuation of the initial combination therapy does not appear to prevent relapse to smoking. Timing of re-treatment and alternative approaches to relapse prevention should be further examined.

Significant parameters in the optimization of MALDI-TOF-MS for synthetic polymers.

One of the most significant issues in any analytical practice is optimization. Optimization and calibration are key factors in quantitation. In matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), instrument optimization is a limitation restricting quantitation. An understanding of the parameters that are most influential and the effects of these parameters on the mass spectrum is required for optimization. This understanding is especially important when characterizing synthetic polymers by MALDI-TOF-MS, due to the breadth of the polymer molecular mass distribution (MMD). Two considerations are important in quantitation, additivity of signal and signal-to-noise (S/N). In this study, the effects of several instrument parameters were studied using an orthogonal experimental design to understand effects on the signal-to-noise (S/N) of a polystyrene distribution. The instrument parameters examined included detector voltage, laser energy, delay time, extraction voltage, and lens voltage. Other parameters considered were polymer concentration and matrix. The results showed detector voltage and delay time were the most influential of the instrument parameters for polystyrene using all trans-retinoic acid (RA) as the matrix. These parameters, as well as laser energy, were most influential for the polystyrene with dithranol as the matrix.

North Central Cancer Treatment Group N10C2 (Alliance): a double-blind placebo-controlled study of magnesium supplements to reduce menopausal hot flashes.

OBJECTIVE: Hot flashes are a common symptom in breast cancer survivors that can negatively impact quality of life. Preliminary data suggested that magnesium might be used as an effective low-cost treatment of hot flashes with minimal adverse effects. METHODS: A four-arm, double-blind, placebo-controlled, randomized trial was conducted. Postmenopausal women with a history of breast cancer and bothersome hot flashes were randomized into treatment groups of magnesium oxide 800 or 1,200 mg daily or corresponding placebo groups at a 2:2:(1:1) ratio. Hot flash frequency and hot flash score (number × mean severity) were measured using a validated hot flash diary. A 1-week baseline period preceded initiation of study medication. The primary endpoint was intrapatient difference in mean hot flash score between baseline and treatment periods, comparing each magnesium group with the combined placebo groups using a gatekeeping procedure. Results were analyzed using repeated-measures and growth curve models on weekly hot flash scores based on a modified intent-to-treat principle. RESULTS: Two hundred eighty-nine women enrolled between December 2011 and March 2013. Study groups were well balanced for baseline characteristics. Mean hot flash scores, mean hot flash frequencies, and associated changes during the treatment period were similar for each group. An increased incidence of diarrhea and a corresponding lower incidence of constipation were reported in magnesium arms compared with placebo. No statistically significant difference in other toxicities or quality-of-life measures was observed. CONCLUSIONS: The results of this trial do not support the use of magnesium oxide for hot flashes.

Phase III randomized, placebo-controlled, double-blind study of intravenous calcium and magnesium to prevent oxaliplatin-induced sensory neurotoxicity (N08CB/Alliance).

PURPOSE: Cumulative neurotoxicity is a prominent toxicity of oxaliplatin-based therapy. Intravenous calcium and magnesium have been extensively used to reduce oxaliplatin-induced neurotoxicity. This trial was designed to definitively test whether calcium/magnesium decreases oxaliplatin-related neurotoxicity. PATIENTS AND METHODS: In all, 353 patients with colon cancer undergoing adjuvant therapy with FOLFOX (fluorouracil, leucovorin, and oxaliplatin) were randomly assigned to intravenous calcium/magnesium before and after oxaliplatin, a placebo before and after, or calcium/magnesium before and placebo after. The primary end point was cumulative neurotoxicity measured by the sensory scale of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Chemotherapy-Induced Peripheral Neuropathy 20 tool. RESULTS: There were no statistically significant neuropathy differences among the study arms as measured by the primary end point or additional measures of neuropathy, including clinician-determined measurement of the time to grade 2 neuropathy by using the National Cancer Institute Common Terminology Criteria for Adverse Events scale or an oxaliplatin-specific neuropathy scale. In addition, calcium/magnesium did not substantially decrease oxaliplatin-induced acute neuropathy. CONCLUSION: This study does not support using calcium/magnesium to protect against oxaliplatin-induced neurotoxicity.

Raman spectroscopic analysis of human skin tissue sections ex-vivo: evaluation of the effects of tissue processing and dewaxing.

Raman spectroscopy coupled with K-means clustering analysis (KMCA) is employed to elucidate the biochemical structure of human skin tissue sections and the effects of tissue processing. Both hand and thigh sections of human cadavers were analyzed in their unprocessed and formalin-fixed, paraffin-processed (FFPP), and subsequently dewaxed forms. In unprocessed sections, KMCA reveals clear differentiation of the stratum corneum (SC), intermediate underlying epithelium, and dermal layers for sections from both anatomical sites. The SC is seen to be relatively rich in lipidic content; the spectrum of the subjacent layers is strongly influenced by the presence of melanin, while that of the dermis is dominated by the characteristics of collagen. For a given anatomical site, little difference in layer structure and biochemistry is observed between samples from different cadavers. However, the hand and thigh sections are consistently differentiated for all cadavers, largely based on lipidic profiles. In dewaxed FFPP samples, while the SC, intermediate, and dermal layers are clearly differentiated by KMCA of Raman maps of tissue sections, the lipidic contributions to the spectra are significantly reduced, with the result that respective skin layers from different anatomical sites become indistinguishable. While efficient at removing the fixing wax, the tissue processing also efficiently removes the structurally similar lipidic components of the skin layers. In studies of dermatological processes in which lipids play an important role, such as wound healing, dewaxed samples are therefore not appropriate. Removal of the lipids does however accentuate the spectral features of the cellular and protein components, which may be more appropriate for retrospective analysis of disease progression and biochemical analysis using tissue banks.

Phase III, randomized, double-blind, placebo-controlled evaluation of pregabalin for alleviating hot flashes, N07C1.

PURPOSE: Hot flashes are a common problem for which effective and safe treatments are needed. The current trial was conducted on the basis of preliminary promising data that pregabalin decreased hot flashes. PATIENTS AND METHODS: A double-blind, placebo-controlled, randomized trial design was used to compare pregabalin at target doses of 75 mg twice daily and 150 mg twice daily with a placebo. Hot flash frequencies and scores (frequency times mean severity) were recorded daily during a baseline week and for six treatment weeks. The primary end point for this study was the change-from-baseline hot flash score during treatment week 6 between the 150 mg twice daily target pregabalin treatment and placebo. Nonparametric Wilcoxon rank sum tests, two-sample t tests, and chi(2) tests were used to compare the primary and secondary hot flash efficacy end points between pregabalin treatments and placebo. RESULTS: Hot flash score changes available for 163 patients during the sixth treatment week compared with a baseline week decreased by 50%, 65%, and 71% in the placebo, and target 75 mg twice daily and 150 mg twice daily pregabalin arms, respectively (P = .009 and P = .007, comparing respective pregabalin arms to the placebo arm). While some toxicities were significantly more common in the pregabalin arms, being more evident with the higher dose, pregabalin was generally well tolerated by most patients. CONCLUSION: Pregabalin decreases hot flashes and is reasonably well tolerated. A target dose of 75 mg twice daily is recommended. Its effects appear to be roughly comparable to what has been reported with gabapentin and with some newer antidepressants.

Phase III, placebo-controlled trial of three doses of citalopram for the treatment of hot flashes: NCCTG trial N05C9.

PURPOSE: Up to 75% of women experience hot flashes, which can negatively impact quality of life. As hot flash physiology is not definitively understood, it cannot be assumed that effective agents represent class effects. Therefore, there is a continued need for rigorous evaluation to identify effective nonhormonal options for hot flash relief. METHODS: A randomized, double-blind trial evaluated citalopram at target doses of 10, 20, or 30 mg/d versus placebo for 6 weeks. Postmenopausal women with at least 14 bothersome hot flashes per week recorded hot flashes for 7 days before starting treatment and were then titrated to their target doses. The primary end point was the change from baseline to 6 weeks in hot flash score. RESULTS: Two hundred fifty-four women were randomly assigned onto this study. Data for hot flash scores and frequencies showed significant improvement in hot flashes with citalopram over placebo, with no significant differences among doses. Reductions in mean hot flash scores were 2.0 (23%), 7.0 (49%), 7.7 (50%), and 10.7 (55%) for placebo and 10, 20, and 30 mg of citalopram, respectively (P

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry interlaboratory comparison of mixtures of polystyrene with different end groups: statistical analysis of mass fractions and mass moments.

A matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) interlaboratory comparison was conducted on mixtures of synthetic polymers having the same repeat unit and closely matching molecular mass distributions but with different end groups. The interlaboratory comparison was designed to see how well the results from a group of experienced laboratories would agree on the mass fraction, and molecular mass distribution, of each polymer in a series of binary mixtures. Polystyrenes of a molecular mass near 9000 u were used. Both polystyrenes were initiated with the same butyl initiator; however, one was terminated with -H (termed PSH) and the other was terminated with -CH2CH2OH (termed PSOH). End group composition of the individual polymers was checked by MALDI-TOF MS and by nuclear magnetic resonance (NMR). Five mixtures were created gravimetrically with mass ratios between 95:5 and 10:90 PSOH/PSH. Mixture compositions where measured by NMR and by Fourier transform infrared spectrometry (FT-IR). NMR and FT-IR were used to benchmark the performance of these methods in comparison to MALDI-TOF MS. Samples of these mixtures were sent to any institution requesting it. A total of 14 institutions participated. Analysis of variance was used to examine the influences of the independent parameters (participating laboratory, MALDI matrix, instrument manufacturer, TOF mass separation mode) on the measured mass fractions and molecular mass distributions for each polymer in each mixture. Two parameters, participating laboratory and instrument manufacturer, were determined to have a statistically significant influence. MALDI matrix and TOF mass separation mode (linear or reflectron) were found not to have a significant influence. Improper mass calibration, inadequate instrument optimization with respect to high signal-to-noise ratio across the entire mass range, and poor data analysis methods (e.g., baseline subtraction and peak integration) seemed to be the greatest obstacles in the correct application of MALDI-TOF MS to this problem. Each of these problems can be addressed with proper laboratory technique.

The influence of electrospray deposition in matrix-assisted laser desorption/ionization mass spectrometry sample preparation for synthetic polymers.

Although electrospray sample deposition in matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS) sample preparation increases the repeatability of both the MALDI signal intensity and the measured molecular mass distribution (MMD), the electrospray sample deposition method may influence the apparent MMD of a synthetic polymer. The MMDs of three polymers of differing thermal stability, polystyrene (PS), poly(ethylene glycol) (PEG), and poly(propylene glycol) (PPG), were studied by MALDI time-of-flight (TOF) MS as the electrospray deposition voltage was varied. The MMDs obtained using the electrospray deposition method were compared with those obtained for hand-spotted samples. No change was observed in the measured polymer MMD when the electrospray deposition voltage was varied in the analysis of PS, but those of PEG and PPG changed at higher electrospray voltages due to increased ion fragmentation. It was also shown that the fragmentation in the hand-spotted samples is dependent on the matrix used in sample preparation.