Low pressure plasma functionalized cellulose fiber for the remediation of petroleum hydrocarbons polluted water.

This work reports the first example of effective purification, at laboratory level, of water polluted by petroleum hydrocarbons, by means of low pressure plasma fluorine grafted cellulose fiber extracted from Spanish Broom. In order to improve the affinity of the cellulosic surface towards water dispersed hydrocarbons, its original hydrophilic character was turned to super-hydrophobic, by a fluorine functionalization. Batch experiments were performed with the aim of studying kinetic and thermodynamic aspects of the adsorption process, as a function of the initial total hydrocarbon load and of the adsorbent amount. The kinetics data showed that the fiber removal efficiency ranged between 80-90% after one minute of contact time, in dependence of the initial hydrocarbon/fiber weight ratio (20-240 mg/g). A maximum adsorption capacity larger than 270 mg/g was estimated by fitting the adsorption isotherm measurements with the Langmuir model. It turned out that the functionalized fiber is capable to perform a significant hydrocarbons removal action if compared to other cellulosic materials reported in the literature. Finally, the efficiency of the plasma modified cellulose fiber, after iterative re-uses, was studied.

Thermal structural evolutions of DMPC-water biomimetic systems investigated by Raman Spectroscopy.

Many cell membranes of living organisms can be represented as phospholipid bilayers immersed into a water environment. The physical-chemical interactions at the membranes/water interface are responsible for the stabilization of the membranes. In addition, the drug efficiency, the pharmaceutical mechanism and the improvement of the drug design can be addressed to the interactions between the membranes-water interface with the drug and to the membrane-drug interface. In this framework, it is important to find membranes models able to simulate and simultaneously simplify the biological systems to better understand both physical and chemical interactions at the interface level. Dimyristoylphosphatidylcholine (DMPC) is a synthetic phospholipid used in order to make Multilamellar Vesicle (MLV), Large Unilamellar Vesicle (LUV) and Giant Unilamellar Vesicle (GUV). In order to understand the mechanisms of vesicle formation, we have analyzed mixtures of DMPC and water by micro-Raman spectroscopy at different temperatures in the range between 10 and 35 °C. Particularly, we analyzed the temperature dependence of the CN vibrational frequency, which appears well correlated to the order degree of the various phases. These investigations, beyond the determination of phospholipid hydrocarbon chains order, provide information about the conformation of the lipid membranes. We have identified the mixture of DMPC/water that is best suited for Raman studies and can be used as an in-vitro model for biological systems. A peculiar frequency shift across the transition gel-ripple-liquid crystalline phases has been proposed as a useful diagnostic marker to detect the "order degree" and subsequently the phases of biomimetic membranes made by DMPC.

Orthogonal electronic coupling in multicentre arylamine mixed-valence compounds based on a dibenzofulvene-thiophene conjugated bridge.

Herein we present organic mixed-valence compounds with an innovative H-shape design, where four redox centres are bridged "vertically" via a dibenzofulvene backbone and "horizontally" via a bis-(dibenzofulvene)-thiophene bridge. These compounds are easily oxidized to stable highly charged radical species which show intense intervalence charge transfer transitions in the near infrared region. Interestingly, depending on the position of the arylamine substituents on the bridge, both vertical and horizontal electron transfer pathways can be optically induced.

Mesomorphism and electrochemistry of thienoviologen liquid crystals.

The thienoviologen series 4,4'-(2,2'-bithiophene-5,5'-diyl)bis(1-alkylpridinium)X2, with = counterion is a new class of electron acceptor materials which show very interesting electrochromic and electrofluorescence properties. Depending on the length, m, of the promesogenic alkyl chains, and on the counterion, thienoviologens might become liquid crystals. Here, we present the mesomorphic behaviour, and the electrochemical and spectroelectrochemical properties in solution of new thienoviologens of the series and (I = iodide; NTf2(-) = bis(tri-fuoromethylsulfonyl)imide) with m = 8, 12. Interestingly, we found that only the compounds are liquid crystals, exhibiting a calamitic behaviour in contrast to the homologous compounds of the series with m = 9-11 and X = NTf2(-), which showed columnar rectangular mesophases. The electrochemical study here reported allowed us to explain for the first time the anomalous behaviour of these thienoviologens already observed in cyclic voltammetry, where two apparently irreversible redox processes occur. This can be explained by a comproportionation reaction in which the neutral species rapidly reduces the dication to the radical-cation, due to its strong reducing power. Electrochemical reduction of the thienoviologens causes electrochromism since a new absorption band, occurring at 660 nm in the electronic spectra, appears with the negative potential bias applied. With a LUMO level of 3.64 eV, similar to those of the C60 and of other n-type materials, these compounds can find applications in several electronics devices, where their liquid crystalline properties can be used to control film morphology and geometry, provided they have good electron mobility.

Antiproliferative effect of millimeter radiation on human erythromyeloid leukemia cell line K562 in culture: ultrastructural- and metabolic-induced changes.

In the present study we compared the proliferation behavior, the ultrastructural morphology and the glycolitic metabolism of K562 cells irradiated by low-power wide-band millimeter waves, with those of sham-exposed K562 cells (control), maintained in the same culture conditions. The gigaHertz radiation treatments, performed between 53-78 10(9) Hz, induced a noticeable inhibition of the cell proliferation that could be related to relevant ultrastructural changes. Such effects brought the irradiated cell system to lose the homeostasis and to trigger defense/reparatory mechanisms in order to reestablish a new steady state. (13)C-Nuclear magnetic resonance data on the kinetic of glucose metabolism demonstrated that the irradiated cells enhanced the glycolitic aerobic pathway, indicating that such system need to produce an extra-bioenergy. Most of the ATP synthesized served probably to perform the above processes resulting in a significant decrease of the proliferation rate without significant cell death increment.

Chitosan and poly(methyl vinyl ether-co-maleic anhydride) microparticles as nasal sustained delivery systems.

An original dosage form for nasal delivery based on the encapsulation of hydrophilic drug in chitosan-poly(methyl vinyl ether-co-maleic anhydride) (CH-PVM/MA) microparticles prepared by spray-drying technique was developed. Microparticles were characterized in terms of morphology, size, swelling properties, encapsulation efficiency and drug release. The physical state of the drug and the polymer was determined by scanning electron microscopy (SEM) and infrared spectroscopy (IR). Propranolol hydrochloride (PH) was a beta-blocker, used for the treatment of hypertension and was chosen as a model of hydrophilic drug. SEM studies showed spherical particles with smooth surfaces for chitosan hydrochloride (CH-HCl), whereas rather gross surface defects resulted from the incorporation of poly(methyl vinyl ether-co-maleic anhydride) (PVM/MA). In vitro release studies revealed a sustained release of propranolol HCl from microparticles and in particular chitosan hydrochloride provided the lowest release of drug.

Anomalous phase transition in dipalmitoylphosphatidylethanolamine/palmitoylphosphatidylcholine/water system.

An anomalous phase transition with a marked rise in specific heat, the isobaric thermal expansion coefficient, and the compressibility coefficient at 62.5 degrees C for an equimolar mixture of 1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine (DPPE) and 1-palmitoyl-sn-glycero-3-phosphocholine (PLPC), in water (34 wt.%) has been shown by differential scanning calorimetry, scanning dilatometry and isothermal compressibility measurements. This transition occurs 15 degrees C above a first-order transition observed in the same system. (31)P and (2)H nuclear magnetic resonance results are consistent with the occurrence of 'defects' in the bilayer in the temperature range between the first and the anomalous phase transitions. It is proposed that conically, PLPC molecules prefer regions with high curvature in the defective bilayer, while DPPE molecules are mostly confined to the flat regions of the bilayers.

In vivo metabolic studies of glucose, ATP and 2,3-DPG in beta-thalassaemia intermedia, heterozygous beta-thalassaemic and normal erythrocytes: 13C and 31P MRS studies.

13C and 31P magnetic resonance spectroscopy was used to characterize the in vivo kinetics of glucose metabolism and intracellular ATP and 2,3-DPG concentrations in erythrocytes obtained from beta-thalassaemia intermedia, heterozygous beta-thalassaemic and normal individuals and maintained in suspension. Except for an upfield chemical shift in the 2P and 3P resonance of 2,3-DPG in the thalassaemia intermedia erythrocytes, the 31P spectra were comparable between all three blood types, showing similar concentrations of ATP (from 4.5 to 5.2 mumol/g Hb) and 2,3-DPG (from 17.2 to 19.7 mumol/g Hb). However, the profile of glucose metabolism was quite different in beta-thalassaemia intermedia erythrocytes, whereas glucose was consumed at a rate of 0.089 +/- 0.035 fmol/cell/h, significantly higher than that of normal (0.032 +/- 0.018 fmol/cell/h; P = 0.01) and heterozygous (0.025 +/- 0.004 fmol/cell/h; P = 0.01) erythrocytes. This near 3-fold faster rate of glucose metabolism in the thalassaemia intermedia erythrocytes could not be accounted for by any increase in glucose flux via the Embden-Meyerhof pathway, since no significant difference in 3-13C-lactate synthesis was observed among the three blood types (in units of fmol/cell/h, normal, 0.021 +/- 0.013; heterozygous, 0.021 +/- 0.006; beta-thalassaemia intermedia 0.045 +/- 0.025). These results reflect an accelerated rate of glucose metabolism in thalassaemia intermedia erythrocytes because the contribution of reticulocytes to this altered pattern of metabolism could be excluded. As the only other route of glucose metabolism in erythrocytes is the pentose phosphate pathway (PPP), these results indicate that the PPP is more active in beta-thalassaemia intermedia erythrocytes, perhaps as a consequence of their elevated intracellular oxidative state.

[Reliability of M-mode and B-mode echocardiography in detection of left intra-atrial masses (author's transl)]. / Affidabilita' della ecocardiografia M-mode/B-mode nella identificazione delle masse intra-atriali sinistre.

Although the role of echocardiography in the detection of left atrial masses is well established, reliability of the method is yet unknown. In 312 patients who underwent cardiac surgery, echocardiographic and anatomic findings were confronted. Pre-operative diagnosis was confirmed in the 8 cases with prolapsing tumors: in the remaining patients we had 5 false positive and 9 false negative diagnosis. So in our experience, sensibility has 73.5 and specificity 98.20.

[Fixed subvalvular left ventricular outflow tract obstruction. Comparison of the diagnostic usefulness of mono- and bi-dimensional echocardiography]. / Ostacolo all'efflusso del ventricolo sinistro sottovalvolare fisso. Confronto tra utilità diagnostica della ecocardiografia mono-bidimensionale.

Because Cross-Sectional Echocardiography offers the advantage of correct spatial orientation, it is said to permit a more exact localization of the level of the outflow tract obstruction and a determination of the nature of the lesion. Our experience confirms that B-Mode Echo is more reliable in diagnosing an extensive sub-valvular narrowing, while the existence of a thin sub-valvular membrane can also be detected by M-Mode examination. The latter has moreover proven very useful in that it records indirect signs of obstruction, such as a mid-systolic closure of the aortic cusps. We therefore suggest that both methods should be employed in studying these patients.

[The pathology of mitral porcine valves. Echocardiographic relief in 5 cases with intra-para-prosthetic regurgitation (author's transl)]. / Patologia delle protesi mitraliche porcine. Rilievi ecocardiografici in cinque casi con rigurgito intra-para-protesico.

Echocardiograms were performed in five patients with severe mitral porcine valve insufficiency due to the para-valvular leak in three cases and to a torn and flail cusp in two cases. We believe that diastolic fluttering of the vusps, decrease or increase of diastolic slope of either the stent or the anterior leaflet as well as decrease of the amplitude of motion of the leaflets cannot be regarded as typical diagnostic features as previously described. In our experience specific signs are only represented by a chaotic diastolic movement of one or both leaflets.

[Right atrial angiosarcoma. report of a case treated successfully by surgery (author's transl)]. / Angiosarcoma dell'atrio destro. Aspetti clinici, ecocardiografici ed istologici in un caso operato con successo.

A 32 years old male presented with symptoms and signs of congestive heart failure. The echocardiographic and angiographic examinations demonstrated a large right atrial tumor prolapsing in the right ventricle through the tricuspid orifice. The patient underwent successful surgical resection of the tumor. Histologically in the lesion was diagnosed as angiosarcoma.

[Aneurysm of ascending aorta associated with aortic valve incompetence. Surgical correction by replacement of right coronary artery in 15 patients (author's transl)]. / L'aneurisma dell'aorta ascendente associata ad insufficienza valvolare. Correzione chirurgica radicale con reimpianto delle coronarie in 15 pazienti.

15 patients with aneurysm of ascending aorta associated with aortic valve incompetence has been treated by the replacement of the aortic valve and ascending aorta with reimplantation of the right coronary artery in 8 patients and both coronary arteries in 7. The operative mortality was 13% (2 patients). The follow up interval ranged from 6 months to three years (mean 20 months) and in all 13 patients there was an improving of functional class. A post-operative angiography was performed in 6 patients and in all of them was demonstrated the patency of the neoostia, a minimum paravalvular leak in one patient, and a pseudoaneurysm in another one. Proving the necessity of complete replacement of aneurysmal aorta, the Authors discuss the technique adopted with particular reference to the problem of reimplantation of the coronary arteries.

[Mitral insufficiency due to rupture of chordae tendineae. The diagnostic usefulness of M-mode echocardiography (author's transl)]. / Insufficienza mitralica da rottura di corde tendinee. Utilità diagnostica della ecocardiografia bidimensionale.

Mitral insufficiency due to ruptured chordae tendinaee is not easily diagnosed by M-mode Echocardiography: of the several patterns that have been described, none has proven quite reliable. Two-dimensional study, on the other hand, seems to be more useful in that it permits to identify an abnormal movement of the involved leaflet which appears quite characteristic. Out of a group of 14 patients we were able to diagnose chordal rupture in 5 proven cases. Further investigation is necessary to ascertain specificity and sensitivity if this echo pattern.

[Uncommon evolution of aneurysm of the ascending aorta in Marfan syndrome. A case report (author's transl)]. / Evoluzione insolita di aneurisma dell'aorta ascendente nella sindrome di Marfan. A proposito di un caso.

The Authors report a case of aneurysm of the ascending aorta in Marfan syndrome, with fatal outcome (2 months after the onset of the symptoms), caused neither by dissection nor by rupture of the aorta, but by serious myocardial involvement due to anoxic damage and acute volume overload of left ventricle. The Authors describe the possible mechanisms of this evolution and point out the usefulness of the identification of this uncommon evolution for a useful and opportune surgical therapy.