Toward the Elucidation of the Competing Role of Evaporation and Thermal Decomposition in Ionic Liquids: A Multitechnique Study of the Vaporization Behavior of 1-Butyl-3-methylimidazolium Hexafluorophosphate under Effusion Conditions.

The evaporation/decomposition behavior of the imidazolium ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (BMImPF6) was investigated in the overall temperature range 425-551 K by means of the molecular-effusion-based techniques Knudsen effusion mass loss (KEML) and Knudsen effusion mass spectrometry (KEMS), using effusion orifices of different size (from 0.2 to 3 mm in diameter). Specific effusion fluxes measured by KEML were found to depend markedly on the orifice size, suggesting the occurrence of a kinetically delayed evaporation/decomposition process. KEMS experiments revealed that other species are present in the vapor phase besides the intact ion pair BMImPF6(g) produced by the simple evaporation BMImPF6(l) = BMImPF6(g), with relative abundances depending on the orifice size-the larger the orifice, the larger the contribution of the BMImPF6(g) species. By combining KEML and KEMS results, the conclusion is drawn that in the investigated temperature range, when small effusion orifices are used, a significant part of the mass loss/volatility of BMImPF6 is due to molecular products formed by decomposition/dissociation processes rather than to evaporated intact ion pairs. Additional experiments performed by nonisothermal thermogravimetry-differential thermal analysis (TG-DTA) further support the evidence of simultaneous evaporation/decomposition, although the conventional decomposition temperature derived from TG curves is much higher than the temperatures covered in effusion experiments. Partial pressures of the BMImPF6(g) species were derived from KEMS spectra and analyzed by second- and third-law methods giving a value of ΔevapH298K° = 145.3 ± 2.9 kJ·mol-1 for the standard evaporation enthalpy of BMImPF6. A comparison is done with the behavior of the 1-butyl-3-methylimidazolium bis(trifluoromethyl)sulfonylimide (BMImNTf2) ionic liquid.

Guanine Oxidation in Double-stranded DNA by MnTMPyP/KHSO(5): At Least Three Independent Reaction Pathways.

In order to better define the mechanism and the products of guanine oxidation within DNA, we investigated the details of the mechanism of guanine oxidation by a metalloporphyrin, Mn-TMPyP, associated to KHSO(5) on oligonucleotides. We found that the three major products of guanine oxidation are formed by independent reaction routes. The oxidized guanidinohydantoin (1) and the proposed spiro compound 3 derivatives are not precursors of imidazolone lesion (Iz). These guanine lesions as well as their degradation products, may account for non-detected guanine oxidation products on oxidatively damaged DNA.

Spontaneous echo-contrast as an in vivo indicator of rheological imbalance in dilatative cardiomyopathy.

The aim of this study was to evaluate coagulative and hemorheologic assessment in patients with dilatative cardiomyopathy with or without spontaneous echo contrast (SEC). We studied 45 patients, 35 males and 10 females (mean age 72.1 +/- 9.2). We measured whole blood viscosity, plasmatic fibrinogen, prothrombin time (PT), activated partial thromboplastin time (aPTT), D-dimer and red cell morphology with Zipursky-Forconi method. Transthoracic and transesophageal echocardiography was performed in all patients to evaluate the presence of SEC in left atrium. We divided all the patients into two groups: the 1st group of 20 patients with SEC and Atrial Fibrillation (AF) in 80% of cases, and the 2nd group of 25 patients without SEC and AF in 31%. Our results show that in patients with SEC there is a statistically significant increase of whole blood viscosity and plasma fibrinogen in comparison with patients without SEC. Red cell morphology in all patients demonstrates a reversed EMI. D-Dimer, was out of the normal range in about 1/3 of the patients in both groups. An analysis of our results points out that in patients with SEC and AF, with a major risk factor for cardioembolic stroke, we have alterations of hemorheologic assessment with an increase of whole blood viscosity and fibrinogen that seems to be caused by an increase of red cells aggregability favoured by fibrinogen. Our conclusions are that SEC in patients with dilatative cardiomyopathy and AF is an important in vivo indicator of hemorheologic imbalance and an important marker for cardioembolic risk stroke evaluation.

[Standard electromyographic and kinesiographic parameters in a sample of healthy population]. / Ricerca parametri elettromiografici e kinesiografici standard in un campione di popolazione sana.

The authors have examined through the electromygraphic-kinesiographic system provided, the mandibolar movements and the electric activity of the masseter and temporal muscles of group of 25 subjects, aged 22-25 (15 women and 10 men), with complete natural dentition, whose history and clinical examination of cranio-mandibular disorders were negative. The aim of the study is to analyse the values come out by these instrumental researches and to compare them with the already existing literature, trying to obtain standard data of "normality", to be used as comparative and diagnostic parameters for this age range and, on the other hand, as a further method of evaluation for electromyiografic-kinesiographic and electromyiographic analysis of subjects suffering from algic-dysfunctional pathology of the cranio-mandibular apparatus. The analysed champion of healthy subjects, with symmetrical electromyiographic normal values (temporan muscles 0.5-2.5 microvolts, masseter muscles 0.5-2.0 microvolts), presents physiological mandibular movementes along the three space axes: furthermore the results outlined by the existing literature, according to which the female champion has a lower muscular electric potential and mandibular dinamic paths than the male champion, are confirmed. The authors point out the importance of computerised clinical research, not only to get data, but also to store them and to be able to compare them in long term.

Botryomycosis: first report of human brain involvement.

A 57-year-old man, previously well except for dental caries and a history of Wolff-Parkinson-White syndrome, presented with marching right-sided motor seizures of sudden onset. Cerebral arteriography and scan demonstrated an avascular left frontal lobe mass. At operation, it was identified as an abscess and was totally excised. Histologically, granules resembling those seen in actinomycosis were demonstrated in the abscess wall, but special stains revealed gram-positive cocci in chains within and outside the granules. Fungal spores, mycelia, or branching filamentous structures were absent. Acid-fast stains were negative, and alpha-hemolytic streptococcus was recovered in pure culture from the abscess. While the patient was convalescing with penicillin therapy, a dental survey revealed the presence of periodontal abscesses which were drained by exodontia. Culture of the tooth sockets showed alpha-hemolytic streptococcus and Staphylococcus aureus. The literature on this relatively rare bacterial disease which histologically resembles actinomycosis is reviewed.

Primary non-skeletal intracranial cartilaginous neoplasms: report of a chondroma and a mesenchymal chondrosarcoma.

The clinical and pathological features of two rare, primary non-skeletal intracranial cartilaginous tumours, a chondroma and a mesenchymal chondrosarcoma, are presented. The literature with respect to clinical, pathological, and possible pathogenetic features is reviewed. The chondroma was successfully resected and the patient has had no recurrence since the operation in 1956. The clinical course of the mesenchymal chondrosarcoma was characterized by rapidly recurring tumour, slowed somewhat by cobalt therapy and frequent surgical interventions. Death occurred some 16 months after the initial resection. There were no metastases.