Ion irradiation of N2O ices and NO2:N2O4 ice mixtures: first steps to understand the evolution of molecules with the N−O bond in space

Astronomical observations towards star forming regions have revealed the presence of molecules with the N-O bond such as NO, N2O, and HNO. These species are considered potential precursors of prebiotic molecules. Thus understanding nitrogen and oxygen chemistry may help us to better understand the origin and evolution of prebiotic molecules in space. However, species with the N−O bond are poorly studied and laboratory works on the effects induced on them by solar wind and galactic cosmic rays are still scarce. For this, we wanted to study the effects of ion bombardment on molecules with the N−O bond. We focus here on N2O ices and NO2:N2O4 = 1:1 ice mixtures (at 16 and 50/60 K) irradiated with 200 keV protons. Infrared transmission spectroscopy (8000−500 cm-¹; 1.25−20 μm) was used to analyze the samples. Irradiation of N2O ices and NO2:N2O4 ice mixtures produces comparable effects independent of the irradiation temperature, NO being the main product. Moreover, we show that the maximum amount of N2O and N2O4 destroyed by irradiation, at the highest dose reached in our experiments, is equal to about 98 and 70%, respectively. The dose range covered in the experiments has been compared with the astrophysical timescale of surface processing in space, showing that irradiation of N2O and NO2:N2O4 mixtures can produce, within 10⁵−10⁸ years, amounts of solid NO ice detectable towards star forming regions by the James Webb Space Telescope

Impact of use of oral anticancer drugs on activity of Italian oncology practices: results of a survey conducted by the Italian Society of Medical Oncology (AIOM)

AIMS AND BACKGROUND: In recent years, the number of oral anticancer drugs used in clinical practice has rapidly increased. The Italian Society of Medical Oncology (AIOM) conducted a survey to describe the impact of the use of oral anticancer drugs on the daily activity of Italian oncology practices. METHODS AND STUDY DESIGN: A survey questionnaire was distributed to the coordinators of the regional sections of AIOM. A 6-month period was considered, from January 1, 2010 to June 30, 2010. The survey addressed (1) quantitative aspects of the use of oral anticancer drugs; (2) practical aspects in the management of patients treated with these drugs; (3) issues related to treatment costs and reimbursement procedures. RESULTS: Thirty-six questionnaires were received from institutions distributed throughout the Italian territory. Oral anticancer drugs (both chemotherapy and molecularly targeted agents) accounted for a significant proportion (17%) of prescribed treatments. Among the responding institutions, there were different dispensation procedures of oral drugs to patients: drugs were dispensed by the pharmacist (57%) or directly by the medical oncologist (23%) or nurse (20%). The medical oncologist played a major role in the communication with patients (73% alone and a further 24% in cooperation with other professional figures) and was the point of reference in the event of side effects in 97% of cases. In most cases, the reimbursement of drug costs was separated ("File F" procedure) from the flat fare received by the hospital for outpatient visits or day-hospital access. CONCLUSIONS: Optimal organization of oral anticancer treatment warrants the cooperation and integration of multiple professional figures. At least three figures are involved in patient management in the hospital: the medical oncologist, the nurse, and the hospital pharmacist. Oral anticancer treatments are associated with specific reimbursement issues: in the majority of cases, the cost of the drug is reimbursed separately from the cost of patient access

Breast cancer "tailored follow-up" in Italian oncology units: a web-based survey

urpose: Breast cancer follow-up procedures after primary treatment are still a controversial issue. Aim of this study was to investigate, through a web-based survey, surveillance methodologies selected by Italian oncologists in everyday clinical practice. Methods: Referents of Italian medical oncology units were invited to participate to the study via e-mail through the SurveyMonkey website. Participants were asked how, in their institution, exams of disease staging and follow-up are planned in asymptomatic women and if surveillance continues beyond the 5th year. Results: Between February and May 2013, 125 out of 233 (53.6%) invited referents of Italian medical oncology units agreed to participate in the survey. Ninety-seven (77.6%) referents state that modalities of breast cancer follow-up are planned according to the risk of disease progression at diagnosis and only 12 (9.6%) oncology units apply the minimal follow-up procedures according to international guidelines. Minimal follow-up is never applied in high risk asymptomatic women. Ninety-eight (78.4%) oncology units continue follow-up in all patients beyond 5 years. Conclusions: Our survey shows that 90.4% of participating Italian oncology units declare they do not apply the minimal breast cancer follow-up procedures after primary treatment in asymptomatic women, as suggested by national and international guidelines. Interestingly, about 80.0% of interviewed referents performs the so called "tailored follow-up", high intensity for high risk, low intensity for low risk patients. There is an urgent need of randomized clinical trials able to determine the effectiveness of risk-based follow-up modalities, their ideal frequency and persistence in time

Circular dichroism and UV-Vis absorption spectroscopic monitoring of production of chiral silver nanoparticles templated by guanosine 50-monophosphate

Herein we report the chemical reduction of silver ions incorporated into chiral supramolecular nanostructures by NaBH4 in buffered (basic) and unbuffered conditions. In situ self-assembly of guanosine 50-monophosphate (50-GMP) templated by Ag(I) and generation of silver nanoparticles (NPs) were continuously monitored by CD and UV-Vis spectroscopy measurements. 50-GMP has been identified as an efficient chiral organic ligand to complex silver ions into a hierarchical helical nanostructure and is a useful capping agent for stabilizing silver NPs with a size diameter lower than 20 nm. The observation of opposite signed bands in the CD spectra of Ag(I)/50-GMP complexes at different pH has suggested the existence of opposite-handed supramolecular helical structures depending on pH. Both helical supramolecular structures induce chirality in the silver NPs during their growth of the same handedness as shown by the CD signals in the plasmon resonance band

REVERSIBLE INTERCONVERSION BETWEEN A SUPRAMOLECULAR POLYMER AND A DISCRETE OCTAMERIC SPECIES FROM A GUANOSINE DERIVATIVE BY DYNAMIC CATION BINDING AND RELEASE

The tunable interconversion between two highly ordered supramolecular motifs (G-quartet K+-templated column and G-ribbon) of a lipophilic guanosine derivative fueled by cation complexation and release in a cryptand [2.2.2] containing guanosine solution is reported. The process is controlled by the sequential addition of acid and base

Synergetic antibacterial effects of silver Nanoparticles@Aloe vera prepared via a green method

Aloe Vera-conjugated Ag nanoparticles (AgNPs@AV hybrids) are synthesized in large quantities by reducing silver nitrate with Aloe Vera pulp extract at room temperature. TEM image reveals that these NPs are predominantly spherical with an average of 25 nm in diameter. The crystal structure of AgNPs@AV is determined by XRD. The cytotoxicity of AgNPs@AV hybrids is detected by carrying out the cell viability measurement on Human Dermal Fibroblasts (HDF) cells, the results show that no obvious cytotoxicity is observed. Compared with Vera gel and Ag NPs (washed from Vera gel) alone, AgNPs@AV hybrids possess more excellent antibacterial activity on E. coli even at very low concentratio