Production of Gas-Phase Uranium Fluoroanions Via Solubilization of Uranium Oxides in the [1-Ethyl-3-Methylimidazolium]+[F(HF)2.3]- Ionic Liquid.

A new methodology for gas-phase uranium ion formation is described in which UO2 is dissolved in neat N-ethyl,N'-methylimidazolium fluorohydrogenate ionic liquid [EMIm+][F(HF)2.3-], yielding a blue-green solution. The solution was diluted with acetonitrile and then analyzed by electrospray ionization mass spectrometry. UF6- (a U(V) species) was observed at m/z = 352, and other than cluster ions derived from the ionic liquid, nothing else was observed. When the sample was analyzed using infusion desorption chemical ionization, UF6- was the base peak, and it was accompanied by a less intense UF5- that most likely was formed by elimination of a fluorine radical from UF6-. Formation of UF6- required dissolution of UO2 followed by or concurrent with oxidation of uranium from the + 4 to the + 5 state and finally formation of the fluorouranate. Dissolution of UO3 produced a bright yellow solution indicative of a U(VI) species; however, electrospray ionization did not produce abundant U-containing ions. The abundant UF6- provides a vehicle for accurate measurement of uranium isotopic abundances free from interference from minor isotopes of other elements and a convenient ion synthesis route that is needed gas-phase structure and reactivity studies like infrared multiphoton dissociation and ion-molecule dissociation and condensation reactions. The reactive fluorohydrogenate ionic liquid may also enable conversion of uranium in oxidic matrices into uranium fluorides that slowly oxidize to uranyl fluoride under ambient conditions, liberating the metal for facile measurement of isotope ratios without extensive chemical separations. Graphical abstract ᅟ.

Mass separator for radioactive isotopes.

A new isotope separator has been designed, constructed, and put into routine operation for separation of 133Xe providing a major advancement and significant cost reduction in preparation of this radioactive isotope. The design features and advantages are discussed that expedite high purity separation of relatively small quantities of this isotope. These advantages could be easily used to expedite separation of other shorter-lived radioactive isotopes.

Fukushima Daiichi reactor source term attribution using cesium isotope ratios from contaminated environmental samples.

RATIONALE: Source term attribution of environmental contamination following the Fukushima Daiichi Nuclear Power Plant (FDNPP) disaster is complicated by a large number of possible similar emission source terms (e.g. FDNPP reactor cores 1-3 and spent fuel ponds 1-4). Cesium isotopic analyses can be utilized to discriminate between environmental contamination from different FDNPP source terms and, if samples are sufficiently temporally resolved, potentially provide insights into the extent of reactor core damage at a given time. METHODS: Rice, soil, mushroom, and soybean samples taken 100-250 km from the FDNPP site were dissolved using microwave digestion. Radiocesium was extracted and purified using two sequential ammonium molybdophosphate-polyacrylonitrile columns, following which (135)Cs/(137) Cs isotope ratios were measured using thermal ionization mass spectrometry (TIMS). Results were compared with data reported previously from locations to the northwest of FDNPP and 30 km to the south of FDNPP. RESULTS: (135)Cs/(137)Cs isotope ratios from samples 100-250 km to the southwest of the FDNPP site show a consistent value of 0.376 ± 0.008. (135)Cs/(137)Cs versus (134)Cs/(137)Cs correlation plots suggest that radiocesium to the southwest is derived from a mixture of FDNPP reactor cores 1, 2, and 3. Conclusions from the cesium isotopic data are in agreement with those derived independently based upon the event chronology combined with meteorological conditions at the time of the disaster. CONCLUSIONS: Cesium isotopic analyses provide a powerful tool for source term discrimination of environmental radiocesium contamination at the FDNPP site. For higher precision source term attribution and forensic determination of the FDNPP core conditions based upon cesium, analyses of a larger number of samples from locations to the north and south of the FDNPP site (particularly time-resolved air filter samples) are needed.

Radioxenon spiked air.

Four of the radioactive xenon isotopes ((131m)Xe, (133m)Xe, (133)Xe and (135)Xe) with half-lives ranging from 9 h to 12 days are produced from nuclear fission and can be detected from days to weeks following their production and release. Being inert gases, they are readily transported through the atmosphere. Sources for release of radioactive xenon isotopes include operating nuclear reactors via leaks in fuel rods, medical isotope production facilities, and nuclear weapons' detonations. They are not normally released from fuel reprocessing due to the short half-lives. The Comprehensive Nuclear-Test-Ban Treaty has led to creation of the International Monitoring System. The International Monitoring System, when fully implemented, will consist of one component with 40 stations monitoring radioactive xenon around the globe. Monitoring these radioactive xenon isotopes is important to the Comprehensive Nuclear-Test-Ban Treaty in determining whether a seismically detected event is or is not a nuclear detonation. A variety of radioactive xenon quality control check standards, quantitatively spiked into various gas matrices, could be used to demonstrate that these stations are operating on the same basis in order to bolster defensibility of data across the International Monitoring System. This paper focuses on Idaho National Laboratory's capability to produce three of the xenon isotopes in pure form and the use of the four xenon isotopes in various combinations to produce radioactive xenon spiked air samples that could be subsequently distributed to participating facilities.

A phase II evaluation of cediranib in the treatment of recurrent or persistent endometrial cancer: An NRG Oncology/Gynecologic Oncology Group study.

PURPOSE: Cediranib is a multi-tyrosine kinase inhibitor targeting vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and fibroblast growth factor (FGF) receptors. This phase II study was conducted to assess activity and tolerability of single-agent cediranib in recurrent/persistent endometrial cancer. PATIENTS AND METHODS: Eligible patients had recurrent or persistent endometrial cancer after receiving one or two prior cytotoxic regimens, measurable disease, and Gynecologic Oncology Group (GOG) performance status of ≤2 (≤1 if two prior cytotoxic regimens given). Cediranib 30mg orally daily for a 28daycycle was administered until disease progression or prohibitive toxicity. Microvessel density (MVD) was measured in tumor tissue from initial hysterectomy specimens and correlated with clinical outcome. Primary endpoints were tumor response and surviving progression-free for six months without subsequent therapy (6-month event-free survival [EFS]). RESULTS: Of 53 patients enrolled, 48 were evaluable for cediranib efficacy and toxicity. Median age was 65.5 years, 52% of patients had received prior radiation, and 73% of patients received only one prior chemotherapy regimen. A partial response was observed in 12.5%. Fourteen patients (29%) had six-month EFS. Median progression-free survival (PFS) was 3.65 months and median overall survival (OS) 12.5 months. No grade 4 or 5 toxicities were observed. A trend towards improved PFS was found in patients whose tumors expressed high MVD. CONCLUSION: Cediranib as a monotherapy treatment for recurrent or persistent endometrial cancer is well tolerated and met protocol set objectives for sufficient activity to warrant further investigation. MVD may be a useful biomarker for activity.

137Cs activities and 135Cs/137Cs isotopic ratios from soils at Idaho National Laboratory: a case study for contaminant source attribution in the vicinity of nuclear facilities.

Radiometric and mass spectrometric analyses of Cs contamination in the environment can reveal the location of Cs emission sources, release mechanisms, modes of transport, prediction of future contamination migration, and attribution of contamination to specific generator(s) and/or process(es). The Subsurface Disposal Area (SDA) at Idaho National Laboratory (INL) represents a complicated case study for demonstrating the current capabilities and limitations to environmental Cs analyses. (137)Cs distribution patterns, (135)Cs/(137)Cs isotope ratios, known Cs chemistry at this site, and historical records enable narrowing the list of possible emission sources and release events to a single source and event, with the SDA identified as the emission source and flood transport of material from within Pit 9 and Trench 48 as the primary release event. These data combined allow refining the possible number of waste generators from dozens to a single generator, with INL on-site research and reactor programs identified as the most likely waste generator. A discussion on the ultimate limitations to the information that (135)Cs/(137)Cs ratios alone can provide is presented and includes (1) uncertainties in the exact date of the fission event and (2) possibility of mixing between different Cs source terms (including nuclear weapons fallout and a source of interest).

Randomised phase II study of docetaxel plus vandetanib versus docetaxel followed by vandetanib in patients with persistent or recurrent epithelial ovarian, fallopian tube or primary peritoneal carcinoma: SWOG S0904.

BACKGROUND: Vandetanib is an oral tyrosine kinase inhibitor of VEGFR-2/3, EGFR and RET, which has demonstrated clinical activity as a single agent and in combination with taxanes. We explored the efficacy, safety and toxicity of docetaxel and vandetanib in women with recurrent ovarian cancer (OC). METHODS: Women with refractory or progressive OC were randomised 1:1 to docetaxel (75 mg/m(2), IV)+vandetanib (100mg daily, PO, D+V) or docetaxel (75 mg/m(2), D). Up to three additional cytotoxic regimens for recurrence and prior anti-angiogenic agents (as primary therapy) were allowed. The primary end-point was progression free survival (PFS). The study had 84% power to detect a PFS hazard ratio of 0.65, using a one-sided P of 0.1. This corresponds to an increase in median PFS from 3.6 months to 5.6 months. Patients progressing on D were allowed to receive single agent vandetanib (D → V). RESULTS: 131 Patients were enrolled; two were excluded. 16% had received prior anti-angiogenic therapy. The median PFS estimates were 3.0 mos (D+V) versus 3.5 (D); HR: 0.99 (80% CI: 0.79-1.26). 61 Patients on D+V were assessable for toxicity; 20(33%) had treatment-related Grade (G) 4 events, primarily haematologic. Similarly, 17 (27%) of 64 patients receiving D had G4 events, primarily haematologic. 27 Evaluable patients crossed-over to V. 1/27(4%) experienced a G4 event. G3 diarrhoea was observed in 4% D → V patients. Median OS was 14 mos (D+V) versus 18 mos (D → V); HR(OS): 1.25 (80% CI: 0.93-1.68). Crossover vandetanib response was 4% (1/27 evaluable patients). High plasma IL-8 levels were associated with response to D+V. CONCLUSIONS: Combination docetaxel+vandetanib did not prolong PFS relative to docetaxel alone in OC patients. No unexpected safety issues were identified.

Generation of gas-phase zirconium fluoroanions by electrospray of an ionic liquid.

RATIONALE: New approaches for forming anions are sought that have strong abundance and no isobaric overlap, attributes that are compatible with the measurement of isotope ratios. Fluoroanions are particularly attractive because fluorine is monoisotopic, and thus will not have overlapping isobars with the isotope of interest. Since many elements do not have positive electron affinity values, they do not form stable negative atomic ions, and hence are not compatible with isotope ratio measurement using high sensitivity isotope ratio mass spectrometers such as accelerator mass spectrometers. METHODS: Zirconium fluoroanions were prepared using the fluorinating ionic liquid (IL) 1-ethyl-3-methylimidazolium fluorohydrogenate, which was used to generate abundant [ZrF5](-) ions using electrospray ionization. The IL was dissolved in acetonitrile, combined with a dilute solution of either Zr(4+) or ZrO(2+), and then electrosprayed. Mass analysis and collision-induced dissociation experiments were conducted using a time-of-flight mass spectrometer. Cluster structures were predicted using density functional theory calculations. RESULTS: The fluorohydrogenate IL solutions generated abundant [ZrF5](-) ions starting from solutions of both Zr(4+) and ZrO(2+). The mass spectra also contained IL-bearing cluster ions, whose compositions indicated the presence of [ZrF6](2-) in solution, a conclusion supported by the structural calculations. Rinsing out the zirconium-IL solution with acetonitrile decreased the IL clusters, but enhanced [ZrF5](-), which was sorbed by the polymeric electrospray supply capillary, and then released upon rinsing. This reduced the ion background in the mass spectrum. CONCLUSIONS: The fluorohydrogenate-IL solutions are a facile way to form zirconium fluoroanions in the gas phase using electrospray. The approach has potential as a source of fluoroanions for isotope ratio measurements, which would enable high-sensitivity measurement of minor zirconium isotopes without overlapping isobars caused by the charge carrier (i.e., the monoisotopic fluorine atoms).

Fluorohydrogenate cluster ions in the gas phase: electrospray ionization mass spectrometry of the [1-ethyl-3-methylimidazolium(+)][F(HF)2.3(-)] ionic liquid.

Electrospray ionization of the fluorohydrogenate ionic liquid [1-ethyl-3-methylimidazolium][F(HF)2.3] ionic liquid was conducted to understand the nature of the anionic species as they exist in the gas phase. Abundant fluorohydrogenate clusters were produced; however, the dominant anion in the clusters was [FHF(-)], and not the fluoride-bound HF dimers or trimers that are seen in solution. Density functional theory (DFT) calculations suggest that HF molecules are bound to the clusters by about 30 kcal/mol. The DFT-calculated structures of the [FHF(-)]-bearing clusters show that the favored interactions of the anions are with the methynic and acetylenic hydrogen atoms on the imidazolium cation, forming planar structures similar to those observed in the solid state. A second series of abundant negative ions was also formed that contained [SiF5(-)] together with the imidazolium cation and the fluorohydrogenate anions that originate from reaction of the spray solution with silicate surfaces.

Pharmacodynamic stimulation of thrombogenesis by angiotensin (1-7) in recurrent ovarian cancer patients receiving gemcitabine and platinum-based chemotherapy.

PURPOSE: This randomized, double-blind, placebo-controlled Phase 2 study evaluated safety and efficacy of A(1-7) for reduction in Grade 3-4 thrombocytopenia in patients receiving myelosuppressive chemotherapy. Pharmacodynamic activity of A(1-7) in platelet production and retention of scheduled dose intensity were also determined. METHODS: Thirty-four patients with ovarian, Fallopian tube, or peritoneal carcinoma receiving gemcitabine and carboplatin or cisplatin were evaluated. Patients were randomized to receive study drug subcutaneously at 100 mcg/kg (n = 11), 300 mcg/kg (n = 13), or placebo (n = 10) following chemotherapy for up to six cycles. Hematologic variables were obtained throughout each treatment cycle. RESULTS: There were no drug-related safety issues. There were no instances of Grade 4 thrombocytopenia in patients who received 100 mcg/kg treatment compared to 6 % of chemotherapy cycles for patients receiving placebo (p = 0.07). The maximal percentage increase in platelet concentration from baseline was higher for patients who received 100 mcg/kg A(1-7) compared to placebo (p = 0.02). This increase was accompanied by a reduction in the nadir absolute neutrophil count (p = 0.04). Relative dose intensity for the combination chemotherapy was higher for patients who received 100 mcg/kg A(1-7) compared to placebo (p = 0.04). There were no differences in outcomes for patients receiving 300 mcg/kg dose compared to placebo. CONCLUSIONS: A 100 mcg/kg dose of A(1-7) was shown to produce pharmacodynamic effects on peripheral blood platelet counts, preserve planned dose intensity, and reduce Grade 3-4 thrombocytopenia following gemcitabine and platinum chemotherapy. These findings are consistent with A(1-7)-induced stimulation of thrombogenesis in the bone marrow following marrow-toxic chemotherapy.

Radioactive cesium isotope ratios as a tool for determining dispersal and re-dispersal mechanisms downwind from the Nevada Nuclear Security Site.

Fractionation of the two longer-lived radioactive cesium isotopes ((135)Cs and (137)Cs) produced by above ground nuclear tests have been measured and used to clarify the dispersal mechanisms of cesium deposited in the area between the Nevada Nuclear Security Site and Lake Mead in the southwestern United States. Fractionation of these isotopes is due to the 135-decay chain requiring several days to completely decay to (135)Cs, and the 137-decay chain less than one hour decay to (137)Cs. Since the Cs precursors are gases, iodine and xenon, the (135)Cs plume was deposited farther downwind than the (137)Cs plume. Sediment core samples were obtained from the Las Vegas arm of Lake Mead, sub-sampled and analyzed for (135)Cs/(137)Cs ratios by thermal ionization mass spectrometry. The layers proved to have nearly identical highly fractionated isotope ratios. This information is consistent with a model where the cesium was initially deposited onto the land area draining into Lake Mead and the composite from all of the above ground shots subsequently washed onto Lake Mead by high intensity rain and wind storms producing a layering of Cs activity, where each layer is a portion of the composite.

Cesium isotope ratios as indicators of nuclear power plant operations.

There are multiple paths by which radioactive cesium can reach the effluent from reactor operations. The radioactive (135)Cs/(137)Cs ratios are controlled by these paths. In an effort to better understand the origin of this radiation, these (135)Cs/(137)Cs ratios in effluents from three power reactor sites have been measured in offsite samples. These ratios are different from global fallout by up to six fold and as such cannot have a significant component from this source. A cesium ratio for a sample collected outside of the plant boundary provides integration over the operating life of the reactor. A sample collected inside the plant at any given time can be much different from this lifetime ratio. The measured cesium ratios vary significantly for the three reactors and indicate that the multiple paths have widely varying levels of contributions. There are too many ways these isotopes can fractionate to be useful for quantitative evaluations of operating parameters in an offsite sample, although it may be possible to obtain limited qualitative information for an onsite sample.

Comparison of focus groups on cancer and employment conducted face to face or by telephone.

Findings from telephone focus groups have not been compared previously to findings from face-to-face focus groups. We conducted four telephone focus groups and five face-to-face focus groups in which a single moderator used the same open-ended questions and discussion facilitation techniques. This comparison was part of a larger study to gain a better understanding of employment experiences after diagnosis of gynecologic cancer. Offering the telephone option made it easier to recruit women from rural areas and geographically distant cities. Interaction between participants occurred in both types of focus group. Content analysis revealed that similar elements of the employment experience after cancer diagnosis were described by telephone and face-to-face participants. Participants disclosed certain emotionally sensitive experiences only in the telephone focus groups. Telephone focus groups provide useful data and can reduce logistical barriers to research participation. Visual anonymity might help some participants feel more comfortable discussing certain personal issues.

Employment and quality of survivorship among women with cancer: domains not captured by quality of life instruments.

BACKGROUND: Many quality of life instruments assess the amount of paid work in combination with role function at home in the same items and do not specifically assess social support in the workplace. The goal of this study was to obtain women's views on the relationship between employment and health-related quality of life. METHODS: A focus group and questionnaire study was conducted among 73 women with gynecologic cancer who were employed at diagnosis and 25 people who provided them with psychosocial support. RESULTS: The women held a variety of blue collar and white collar jobs at diagnosis. Employment provided a strong sense of accomplishment and a welcome distraction during treatment. The employment experience was described as distinct from role function at home. No one equated working more hours with better quality of life. Social support at work could be poor at the same time that support from family and friends grew stronger. CONCLUSIONS: The contribution to their quality of life that cancer survivors feel they receive from employment may not be linearly related to the quantity of their role function in the workplace. Employment-related items could be useful as an adjunct to standard quality of life measures.

Cancer-related tasks involving employment: opportunities for clinical assistance.

Many cancer survivors experience unmet psychosocial needs related to their jobs, and women often fare worse than men in this regard. However, little research exists on ways to assist patients with cancer in preventing or managing common job problems. We conducted focus groups and a survey among 73 women who were employed at the time of presentation of a gynecologic cancer. We compared the findings with existing recommendations and professional standards for occupational rehabilitation. Participants described different cancer-related employment tasks in three time periods: just after diagnosis, during primary treatment, and after primary treatment is completed. The more difficult tasks included communicating with supervisors and coworkers, determining company policies, applying for employer-sponsored benefits, handling finances, managing symptoms on returning to work, finding effective solutions to cancer-related job problems, leaving the job with dignity if too sick or if the job ended, and making career plans. The cancer care team may be able to help meet the psychosocial needs of employed cancer survivors by screening for job concerns, providing information, formulating a return-to-work plan, treating symptoms, consulting with professionals who have employment-related expertise, and giving other forms of assistance.

Blunt abdominal trauma with ruptured 16-week cornual ectopic pregnancy.

Trauma is the leading cause of nonobstetric morbidity and mortality in pregnancy. Care of the pregnant trauma patient is well documented in the medical literature; however, little has been written about the management of trauma patients with ectopic or cornual pregnancy. Herein, we report the previously undocumented occurrence of a traumatic rupture of a cornual ectopic pregnancy. The use of trauma ultrasound, computerized tomography, as well as obstetrical evaluation prevented an imminent life-threatening complication of this patient's pregnancy.

Continuous abdominal fascial closure: a randomized controlled trial of poly(L-lactide/glycolide).

OBJECTIVE: The objective was to compare the handling characteristics and

Phase III trial of paclitaxel at two dose levels, the higher dose accompanied by filgrastim at two dose levels in platinum-pretreated epithelial ovarian cancer: an intergroup study.

PURPOSE: To determine if increasing the dose of paclitaxel increases the probability of clinical response, progression-free survival, or overall survival in women who have persistent or recurrent ovarian cancer, and whether doubling the dose of prophylactic filgrastim accompanying the higher paclitaxel dose decreases the frequency of neutropenic fever. PATIENTS AND METHODS: Consenting patients with persistent, recurrent, or progressing ovarian cancer, despite first-line platinum therapy (but no prior taxane), were randomly assigned to paclitaxel 135 mg/m2, 175 mg/m2, or 250 mg/m2 over 24 hours every 3 weeks. Patients receiving paclitaxel 250 mg/m2 were also randomly assigned to 5 or 10 microg/kg of filgrastim per day subcutaneously. RESULTS: Accession to the paclitaxel 135-mg/m2 arm was closed early. Among the 271 patients on the other regimens with measurable disease, partial and complete response on paclitaxel 250 mg/m2 (36%) was significantly higher than on 175 mg/m2 (27%, P =.027). This difference was more evident among patients who never responded to prior platinum. However, progression-free and overall survival results were similar. The median durations of overall survival were 13.1 and 12.3 months for paclitaxel 175 mg/m2 and 250 mg/m2, respectively. Thrombocytopenia, neuropathy, and myalgia were greater with paclitaxel 250 mg/m2 (P <.05). The incidence of neutropenic fever after the first cycle of paclitaxel 250 mg/m2 was 19% and 18% on the 5-microg/kg and 10-microg/kg filgrastim dose, respectively (22% for paclitaxel 175 mg/m2 without filgrastim). CONCLUSION: Paclitaxel exhibits a dose effect with regard to response rate, but there is more toxicity and no survival benefit to justify paclitaxel 250 mg/m2 plus filgrastim. Doubling the filgrastim dose from 5 to 10 microg/kg did not reduce the probability of neutropenic fever after high-dose paclitaxel.