Bringing Machine-Learning Enhanced Quantum Chemistry and Microwave Spectroscopy to Conformational Landscape Exploration: the Paradigmatic Case of 4-Fluoro-Threonine

A combined experimental and theoretical study has been carried out on 4-fluoro-threonine, the only naturally occurring fluorinated amino acid. Fluorination of the methyl group significantly increases the conformational complexity with respect to the parent amino acid threonine. The conformational landscape has been characterized in great detail, with special attention given to the inter-conversion pathways between different conformers. This led to the identification of 13 stable low-energy minima. The equilibrium population of so many conformers produces a very complicated and congested rotational spectrum that could be assigned through a strategy that combines several levels of quantum chemical calculations with the principles of machine learning. Twelve conformers out of 13 could be experimentally characterized. The results obtained from the analysis of the intra-molecular interactions can be exploited to accurately model fluorine-substitution effects in biomolecules.

Proximate, fatty acids and metals in edible marine bivalves from Italian market: Beneficial and risk for consumers health

Seafood is recognized as a healthy food choice due to high contents of essential nutrients, including polyunsaturated fatty acids (PUFAs) of the n-3 family. However, seafood is often contaminated by toxic compounds, which have adverse effects on human health. The aim of this study was to provide information about the percentage of edible part, condition index and the benefit and risk for human consumers health associated to the consumption of eight bivalve species (Flexopecten glaber, Mimachlamys varia, Modiolus barbatus, Mytilus galloprovincialis, Ostrea edulis, Ruditapes philippinarum, Solen marginatus and Venus verrucosa) of high commercial value, purchased from Taranto local fish markets. High percentage of edibility and condition index were found in all analysed species. The relatively high protein content, low levels of lipid and high percentage of healthy n-3 PUFAs make M. varia, O. edulis, S. marginatus, M. galloprovincialis, M. barbatus more suitable for benefit to consumers. Provisional tolerable weekly intake and hazard index calculated on the basis of trace metals in edible tissues, indicated specific recommendations for a responsible daily consumption of shellfish. For the most part of studied species, the estimated balance between beneficial and risk for consumers recommend a daily portion (RDP) lesser of 60 g/person/day than M. galloprovincialis, O. edulis and R. philippinarum (≥60 g/person/day). Careful risk-benefit considerations should promote seafood consumption while minimizing exposure to toxic contaminants.

Laboratory measurements and astronomical search for cyanomethanimine

CONTEXT

C-cyanomethanimine (HNCHCN), existing in the two Z and E isomeric forms, is a key prebiotic molecule, but, so far, only the E isomer has been detected toward the massive star-forming region. Sagittarius B2(N) using transitions in the radio wavelength domain.

AIMS

With the aim of detecting HNCHCN in Sun-like-star forming regions, the laboratory investigation of its rotational spectrum has been extended to the millimeter-/submillimeter-wave (mm-/submm-) spectral window in which several unbiased spectral surveys have been already carried out.

METHODS

High-resolution laboratory measurements of the rotational spectrum of C-cyanomethanimine were carried out in the 100-420 GHz range using a frequency-modulation absorption spectrometer. We then searched for the C-cyanomethanimine spectral features in the mm-wave range using the high-sensitivity and unbiased spectral surveys obtained with the IRAM 30-m antenna in the ASAI context, the earliest stages of star formation from starless to evolved Class I objects being sampled.

RESULTS

For both the Z and E isomers, the spectroscopic work has led to an improved and extended knowledge of the spectroscopic parameters, thus providing accurate predictions of the rotational signatures up to ~700 GHz. So far, no C-cyanomethanimine emission has been detected toward the ASAI targets, and upper limits of the column density of ~ 10¹¹-10¹² cm^-2 could only be derived. Consequently, the C-cyanomethanimine abundances have to be less than a few 10^-10 for starless and hot-corinos. A less stringent constraint, ≤ 10^-9, is obtained for shocks sites.

CONCLUSIONS

The combination of the upper limits of the abundances of C-cyanomethanimine together with accurate laboratory frequencies up to ~ 700 GHz poses the basis for future higher sensitivity searches around Sun-like-star forming regions. For compact (typically less than 1″) and chemically enriched sources such as hot-corinos, the use of interferometers as NOEMA and ALMA in their extended configurations are clearly needed.

Assessing hand hygiene compliance among healthcare workers in six Intensive Care Units

INTRODUCTION

Healthcare associated infections (HAIs) are a cause of high morbidity, disability and reduced quality of life, as well as mortality and rising costs for health systems. Preventing the HAI risk by planning and implementing effective preventive strategies is important to safeguard patient health.

METHODS

The study aimed to evaluate the presence of procedures and protocols for infection control, to assess the adhesion to the different aspects of hand hygiene (HH) and hand washing technique by healthcare workers in six ICUs. A perspective observational study was conducted in six ICUs. In each ICU, the adherence by health care workers to both hand hygiene practices and standard precautions was assessed, as well as the presence of procedures and written protocols.

RESULTS

The findings showed that in all the involved ICUs, 73 of 142 required protocols and procedures were available. Specifically, 59 of 79 were available for general measure of risk control, 12 of 15 for hand hygiene, and 24 of 48 for standard precautions and isolation measures. Also, the results showed highly variable levels of adherence to the best hygiene practices in all the ICUs involved in the study, with compliance rates ranging from 3% to 100%, and 73 of 142 required protocols were available at the study time.

CONCLUSIONS

Overall, the involved ICUs showed low levels of adherence to best hygiene practices. This suggests the need to implement immediate strategies for infection control in the ICUs. A multidisciplinary intervention could be effective in preventing and control the HAI risk.score was reached only by the third year students with regard to the proper HH. The level of knowledge about HAI was inadequate.A periodically check of nursing students' knowledge would be advisable in order to fill any gaps, improve training, reduce HAI and increase prevention measures compliance.

[Occupational and environmental cancer in southern Sardinia: a survey on ten years of hospitalizations]

Based on hospital discharges in 1001-2010, we calculated risk of tumours with an elevated occupational and environmental etiological fraction by health district of residence within the Local Health Unit (LHU) N. 8 of Sardinia. With reference to the age and gender-specific hospitalization rates of the whole LHU, residents in the urban Cagliari health district showed an excess risk of haemolymphopoietic cancer (RR = 1.07; 95% CI 1.03-1.12) and bladder cancer (RR = 1.10; 95% CI 1.05-1.16); in both instances, risks were higher among female residents. The highest excess risk for lung cancer was observed among residents in the Quartu-Parteolla health district (RR = 1.13; 95% CI 1.05-1.21), and it was slightly higher among male residents. The results appear to confirm the role of urban factors in increasing cancer risk.

The pharmacokinetics of one single preoperative dose of metronidazole or tinidazole

Eight patients who were subjected to colorectal surgery received 1500 mg metronidazole and another 8 patients 1600 mg tinidazole. The two groups of patients were comparable in respect to age, body size, diagnoses, types of operations, premedication, and anaesthesia. Concentrations of the parent compounds and hydroxy-metronidazole were determined by high pressure liquid chromatography in serum and tissues (subcutaneous fat, rectus abdominal muscle, peritoneum, greater omentum, distal ileum, colon, appendix). The serum and tissue concentrations of metronidazole and tinidazole were within overlapping ranges. Hydroxy-metronidazole but not hydroxy-tinidazole was detected. The total area under the serum curves was 505 (SD: +/- 181) mg . h/l for metronidazole, 137 (+/- 38) mg . h/l for hydroxy-metronidazole, and 810 (+/- 286) mg . h/l for tinidazole. The serum half-life values in the same order were 8.5, 11.2, and 14.2 hours. The distribution volume (Vd,area) were 30.1 liter for metronidazole and 38.8 liter for tinidazole. The range of tissue concentrations were completely overlapping. The two regimens can, consequently, be assessed as pharmacokinetically similar.