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Hydrogen bonds play a crucial role in chemistry and biology. Numerous experimental and theoretical studies have been devoted to the elucidation of the structures and the energetics of hydrogen bonds, establishing key features of both intra-molecular and inter-molecular hydrogen bonds by means of different spectroscopic measurements and quantum chemical calculations. In particular, the interaction between acids and water occurs via formation of a hydrogen bond with the acid as the hydrogen donor and the water oxygen as the acceptor. If an electronegative center exists in the acid, another weaker hydrogen bond may be formed with this center as the hydrogen acceptor and the water as the hydrogen donor. Formation of two hydrogen bonds therefore constructs a ring-like structure in the 1:1 acid-water complex. Microwave spectroscopy studies of the dimers of nitric acid [1], sulfuric acid [2], and several carboxylic acids (formic [3], acetic [4], propanonic [5], trifluoroacetic acid [6], trans- and gauche-difluoroacetic [7]) with water have confirmed this structural feature. In many of such spectra, large amplitude motions of the water moiety produce a hyperfine structure of the transition lines. With the aim of getting insight on the behaviour of this kind of dimers, we recorded and assigned the mua- and mub-type rotational spectra of the water complex with both the s-cis and s-trans forms of acrylic acid, the simplest unsaturated carboxylic acid. Besides the parent species, also the spectra of eight isotopomers (COOH-H218O, COOH-D2O, COOD-H2O, COOD-D2O, COOH-DOH, COOH-HOD, COOD-DOH, COOD-HOD) for each conformer were analysed. From the comparison of the rotational constants of all species, precise structural information is obtained. The mub-type transition lines of the parent species and 18O isotopomers are split in two components and a picture of the potential energy surface that leads to this motion has been attempted by quantum-mechanical calculations.

Background Recent guidelines recommend early surgical treatment of hip fractures in the elderly. Understanding the factors that delay surgical intervention is essential in order to facilitate early treatment. The aim of the present study is to determine the factors delaying surgical treatment of hip fractures in elderly patients for more than 2 days. Methods Assessment of hospital discharge records and chart review of 1733 consecutive patients undergoing surgery for hip fractures between 2004-2007 at the two Italian wards of Sant�Orsola-Malpighi Hospital, Bologna (N=1286) and S. Maria della Scaletta Hospital, Imola (N=447). Logistic regression models were used to examine potential predictors of surgery delay including gender, age, ward, comorbidity, type of intervention (partial or total hip replacement, reduction and internal fixation), International Normalized Ratio (INR), Haemoglobin (Hb), American Society of Anaesthesiologists (ASA) score, and day of admission (categorized as Monday to Wednesday, Thurday-Friday, Saturday-Sunday). Results 923 (53.3%) patients were operated within 2 days of admission to the hospital. Age, arrhythmia, type of intervention (partial or total hip replacement), INR score>1.5 and an ASA score of 4 compared to 1-2, admission on Thurdays-Friday or Saturday-Sunday and ward significantly predicted a surgery delay of more than 2 days. The Hosmer-Lemeshow test denoted a good model fit (χ�=12.2, p=0.14). Conclusions Both organization and medical problems accounted for delays of surgical treatment of hip fractures. A multidisciplinary approach, with early input by medical and anaesthetic teams, is needed for managing elderly patients with hip fracture. The availability of the operating theater during the weekend and established protocols aimed to optimize the patient flow logistics may be crucial to make hospitals more patient-centered and to improve patient outcomes

2-Oxazolidinone (systematic name 1,3-oxazolidin-2-one) is a five-member heterocyclic ring exhibiting potential medicinal roperties. It is the pharmacophore of a class of antimicrobial agents which have a unique structure and good activity gainst Gram-positive pathogenic bacteria (e.g. linezolid, the first in clinical use 2-oxazolidinone antibiotic). Often the functionality of drugs is related to their conformational flexibility and ability to form non covalent interactions with ts urroundings. In order to understand how substitution affect these properties, a series of oxazolidone compounds has been studied by means of millimeter wave free jet Stark modulated absorption spectroscopy [1] and quantum mechanical calculations. The achieved data will be presented. [1] C. Calabrese, A. Maris, L. Evangelisti, L.B. Favero, S. Melandri and W. Caminati, J. Phys. Chem. A, 117, 13712 (2013).

Viene svolta un’accurata messa a punto delle più recenti acquisizioni scientifiche e cliniche in tema di implantologia dentaria, con particolare riferimento a biomateriali e biotecnologie, capacità dell’imaging, indicazioni, tecniche di realizzazione, valutazione delle resa del trattamento, aspetti di attività chirurgica, rapporti con l’estetica, impiego in ortodontia, aspetti psicologici. Per molti di questi argomenti si affrontano anche i complementari aspetti di interesse medico-legale, quali l’inquadramento normativo della sperimentazione, la responsabilità professionale nell’insuccesso, l’obbligo di informazione al paziente, la valutazione del danno, l’invocabilità della “speciale difficoltà”, le problematiche intrinseche della componente estetica del trattamento, le criticità medico-legali degli impianti a fini ortodontici e nell’approccio psicologico al paziente. Una sintesi, dunque, degli aspetti tecnici, clinici e medico-legali operata da esperti di particolare qualificazione nell’ambito della propria competenza in un settore odontoiatrico di grande applicazione per il quale si pongono interrogativi con delicati risvolti clinici, deontologici e medico-forensi.

OBJECTIVE - It is still controversial whether sirolimus-eluting stent (SES) and paclitaxel-eluting stent (PES) are equally effective in patients with diabetes. In these patients, multiple individual variables may be responsible for neointimal hyperplasia, thus making difficult the comparison of the two drug-eluting stents (DES). RESEARCH DESIGN AND METHODS - We designed a prospective, randomized study to compare the efficacy in prevention of restenosis of SES and PES, both implanted in the same diabetic patient with multiple de novo coronary artery lesions undergoing elective percutaneous coronary intervention. We enrolled 60 patients with diabetes with at least two significant de novo angiographic stenoses in different coronary segments. The primary end point was in-stent late luminal loss (LLL) at 8-month angiographic follow-up. RESULTS - A total of 120 lesions were successfully treated with the randomly assigned DES (SES, n=60; PES, n=60). In-stent LLL was lower in the SES than in the PES group (0.26 ± 0.4 vs. 0.50 ± 0.6 mm; P = 0.01). Coronary lesions treated with SES presented a reduced in-stent LLL in 40 (68%) patients, while PES resulted in a lower in-stent LLL in 19 (32%) patients (P = 0.0002). At multivariable analysis, the type of DES implanted was the only independent predictor of in-stent LLL (odds ratio 2.3 [95% CI 1.1-5.0]; P = 0.03). CONCLUSIONS - SES directly compared with PES in the same diabetic patient is associated with a decrease in the extent of in-stent LLL at 8 months, suggesting a reduced risk of restenosis. © 2008 by the American Diabetes Association.

A cladistic analysis of Megadontosuchus arduini from the middle Eocene of Monte Duello (NE Italy) confirms its tomistomine relationships, but the low number of scorable characters determines a low resolution within the tomistomine clade. However, Megadontosuchus is clearly distinct from the other Eocene European or North African tomistomines, in having a moderate elongated but robust rostrum, massive maxillary and dentary teeth and large supratemporal fenestrae. The rostrum and teeth characteristics could indicate that M. arduini had a degree of feeding specialization intermediate between Maroccosuchus zennaroi and the Eocene European tomistomines. A summary of tomistomine palaeobiogeo− graphy suggests that despite only one species with a rather restricted range survives at present, such a clade had a glorious past with a world wide distribution documented by a conspicuous fossil record that starts at least in the early Eocene. At present, a detailed knowledge of tomistomine palaeobiogeography is hindered by the lack of modern taxonomic revisions of some fossil remains and therefore by the poor understanding of phylogenetic relationships.

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