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In this paper we compare a bottom-up approach and a top-down technique to realize efficient SERS substrates for plasmonic "label-free" nanobiosensors. We demonstrate that SERS enhancement factors of the order of ~ 107 can be reproducibly obtained using Au photonic quasi crystals arrays of nano-pillars.

The control of light with artificial structures is one of the key issues in modern photonics. The last decade has been characterized by artificial electromagnetic (EM) materials, including photonic crystals (PCs) and photonic quasi-crystals (PQCs), making these very attractive given that there are new possibilities to control the EM field in innovative way. Quasiperiodic crystals (QCs) are a new class of materials that have fascinating optical properties lying somewhere between those of disordered and period structures.[1-3] With the use of PCs and PQCs, it is possible to synthesize novel artificial structures characterized by selective EM responses, which, in turn, undergo significant frequency shifts, in presence of biological material. Since the initial discovery of Surface-Enhanced Raman Scattering (SERS), an increased amount of work has been done on the research of substrates for highly efficient Raman scattering enhancement due to their extraordinary potential for trace analysis and biological tags. Recently, the plasmonic optical responses of metal nanoparticles, based on Localized Surface Plasmon Resonances (LSPR) in the visible and near IR region, has been intensively researched. It has been demonstrated that the plasmon resonance is closely related to the size and shape of metal nanoparticles and to the dielectric properties of the surrounding medium. In SERS spectroscopy it is of crucial importance to develop systems of interacting metal nanostructures capable of producing high field enhancement with highly reproducible characteristics on controllable metal-dielectric substrates. In the present work we studied artificial electromagnetic (EM) nanomaterials to develop innovative plasmonic nanobiosensors based on SERS and working in the visible frequency band. Au photonic crystals (PCs) and photonic quasi crystals (PQCs) are proposed for the engineering of reproducible SERS substrates. Using a molecular monolayer of pMA (p-mercaptoaniline) as a Raman reporter, we show that high values of SERS enhancement factors can be achieved in photonic structures. We have demonstrated experimentally measured SERS enhancement 1) GSERS=1.3*107 in lithographically defined Square-based periodic PCs of triangular-shape with side size d=200nm and pitch A=300nm, 2) GSERS=1.4*107 in Thue Morse (ThMo) PQC arrays of Au nano cylinders with 185nm side size and 80nm minimum interparticle separation, and, 3) GSERS=1.4*108 in 8-fold PQC arrays of cylinders with diameter D=125nm and FF= 0.18. The resulting PQC nanostructured films, both ThMo and octagonal arrangements, can serve as good SERS substrate, exhibit large electromagnetic field enhancement factors for pMA, and can readily be used in ultrasensitive, molecule-specific sensing utilizing vibrational signatures. To demonstrate the feasibility of the fabricated nanostructures as efficient SERS substrates for biological applications, we devised a method to deposit single cells (human prostatic) on the photonic surfaces. Preliminary results on SERS sampling of single prostatic human cells indicated that the present engineered metamaterials may be used as an ultrasensitive Raman probe to monitor subtle molecular changes in the cell and open up interesting new opportunities in biosensing.

Summary In this paper we present efficient SERS substrates for plasmonic "label-free" nanobiosensors realized by electron beam lithograhy. We demonstrate that SERS enhancement factors of the order of ~107 can be reproducibly obtained using Au photonic quasi crystals arrays of nano-pillars. Introduction Since the initial discovery of surface-enhanced Raman scattering (SERS), an increased amount of work has been done on the research of substrates for highly efficient Raman scattering enhancement due to their extraordinary potential for trace analysis and biological tags. Recently, the plasmonic optical responses of metal nanoparticles based on localized surface plasmon resonances (LSPR) and significant fluorescence enhancement in the visible and near IR region, have been intensively researched. Many groups have demonstrated that the plasmon resonance is closely related to the size and shape of metal nanoparticles and the dielectric properties of the surrounding medium. The possibility of engineering complex metal nanoparticle arrays with distinctive plasmonic resonances extending across the entire visible spectrum can have a significant impact on the design and fabrication of novel nanodevices based on broadband plasmonic enhancement. In the present work we studied artificial electromagnetic (EM) nanomaterials such as photonic crystals (PCs) and photonic quasi-crystals (PQCs) to develop innovative plasmonic nanobiosensors based on SERS and working in the visible frequency band. With the use of PCs and PQCs, it is possible to synthesize novel artificial structures characterized by selective EM responses, which, in turn, undergo significant frequency shifts, in presence of biological material. Using a molecular monolayer of pMA (p-mercaptoaniline) as a Raman reporter, we show that higher values of SERS enhancement factors can be achieved in PQCs structures compared to their periodic counterparts. To demonstrate the feasibility of the fabricated nanostructures as efficient SERS substrates for biological applications, we devised a method to deposit single cells (human prostatic) on the photonic surfaces. Discussion In this work, our engineered substrates were manufactured using direct-write electron beam lithography (EBL). We fabricated 2D PQCs operating in the frequency band of visible based on resonant metallic structures in a Thue-Morse (ThMo) arrangement.1,2 The EBL process is essential to achieve the well-control of size, shape, composition, and configuration of plasmonic nanostructures. In fig. 1a, a SEM image of the 2D Au QC realized, with 60nm-Au nanopillars side size of 185nm in a ThMo sequence with a step of 270nm is shown. Fig. 1b shows the Stokes Raman spectra of pMA molecular monolayers deposited on top of the Au PQC. The three dominant Stokes modes (390, 1077, 1590 cm-1), arising from bending and stretching modes in the benzene rings of the pMA molecule, can clearly be distinguished in all the spectra. SERS spectra were collected with a 785 nm laser resulting in power at the sampling point of ~1.7 mW. To demonstrate the feasibility of the fabricated nanostructures as efficient SERS substrates for biological applications, we devised a method to deposit single cells (human prostatic) on the photonic surfaces. In Fig. 2a is represented the Raman image obtained by confocal sampling of one of the cells. Image reconstruction was performed by use of the peak intensity at 1320 cm-1, a signal characteristic of the wagging vibration of CH2 groups in the glycine unit. Fig.2b represents the spectra collected at position A. Spectra collected at different locations within the cell boundary display a widely variable scattering response. This ultrasensitive Raman probe may be advantageously used to monitor subtle molecular changes in the cell and opens up interesting new opportunities in the early diagnosis of diseases, especially in connection to tissue analysis. Conclusions In this work SERS substrates based on PCs and PQCs are presented. The 2D-PQC pattern with ThMo arranged Au nanorods with a side size of 185 nm and a depth of 60 nm has been uniformly formed by EBL in areas of 200 µm2. The engineered substrates exhibit very efficient Raman scattering enhancement estimated using pMA (p-mercaptoaniline) as a probe molecule which is attributed to the coupling electromagnetic SERS enhancement mechanism with additional localization field within nanoparticles on glass. We have demonstrated an experimentally measured SERS enhancement GSERS=1.32*107 in lithographically defined PQC arrays of Au nanoparticles. The resulting PQC nanostructured film can serve as good SERS substrate, exhibits large electromagnetic field enhancement factors for pMA, and can readily be used in ultrasensitive, molecule-specific sensing utilizing vibrational signatures. Preliminary results on SERS sampling of single prostatic human cells indicated that the present engineered metamaterials may be used as an ultrasensitive Raman probe to monitor subtle molecular changes in the cell and open up interesting new opportunities in biosensing, specially in connection to tissue analysis.- References [1]L. Moretti and V. Mocella, Opt. Exp., 15, 15314, 2007. [2]M. Rippa, R. Capasso, P. Mormile, S. De Nicola, M. Zanella, , L. Manna, G. Nenna, L. Petti, Nanoscale, 5, 331.

In this paper we compare a bottom-up approach and a top-down technique to realize efficient SERS substrates for plasmonic "label-free" nanobiosensors. We demonstrate that SERS enhancement factors of the order of ~ 107 can be reproducibly obtained using Au photonic quasi crystals arrays of nano-pillars

The control of light with artificial structures is one of the key issues in modern photonics. Since the initial discovery of Surface-Enhanced Raman Scattering (SERS), an increased amount of work has been done on the research of substrates for highly efficient Raman scattering enhancement due to their extraordinary potential for trace analysis and biological tags. Recently, the plasmonic optical responses of metal nanoparticles, based on Localized Surface Plasmon Resonances (LSPR) in the visible and near IR region, has been intensively researched. It has been demonstrated that the plasmon resonance is closely related to the size and shape of metal nanoparticles and to the dielectric properties of the surrounding medium. In SERS spectroscopy it is of crucial importance to develop systems of interacting metal nanostructures capable of producing high field enhancement with highly reproducible characteristics on controllable metal-dielectric substrates. The possibility of engineering complex metal nanoparticle arrays with distinctive plasmonic resonances extending across the entire visible spectrum can have a significant impact on the design and fabrication of novel nanodevices based on broadband plasmonic enhancement. Electron beam lithography (EBL) is an ideal method for the fabrication of engineered SERS substrates by controlling both the shape and the position of each particle at the nanoscale. In the present work we studied artificial electromagnetic (EM) nanomaterials to develop innovative plasmonic nanobiosensors based on SERS and working in the visible frequency band. Au photonic crystals (PCs) and photonic quasi crystals (PQCs) are proposed for the engineering of reproducible SERS substrates. Using a molecular monolayer of pMA (p-mercaptoaniline) as a Raman reporter, we show that high values of SERS enhancement factors can be achieved in photonic structures. To demonstrate the feasibility of the fabricated nanostructures as efficient SERS substrates for biological applications, we devised a method to deposit single cells (human prostatic) on the photonic surfaces. Preliminary results on SERS sampling of single prostatic human cells indicated that the present engineered metamaterials may be used as an ultrasensitive Raman probe to monitor subtle molecular changes in the cell and open up interesting new opportunities in biosensing.

Current research efforts on cutting-edge materials, such as Photonic Crystals (PCs), self-organizing nanomaterials, and polymeric and composite materials, are focused on obtaining novel or unique properties enabled by specialized molecular electronic, structural designs or dopants. While most metamaterials developed to date consist of passive material constituents, several studies have emerged where material constituents containing electrooptics, nonlinear optics, or active (gain) material are involved [1]. Control and tuning of the metamaterial electromagnetic response are gaining research interests as a natural research development to attain functionality in metamaterials [2, 3]. In a photonic device application, liquid crystal (LC) is the choice material when a control and tuning is pursued, as evidenced in wide applications to the optical display and photonics switching devices. But, often the geometrical properties of the photonic structures give problems for controlling the alignment of the LC. In this paper we studied a reproducible way to create specific orientational order fields in liquid crystals by means of novel nanostructured aligning surfaces. Two different metamaterial-liquid crystal structures are fabricated with the metamaterials as LC alignment layers. E-beam lithography was used to pattern the electron-sensitive polymer 1D PC structures. The nanostructured aligning surfaces have been characterized by Scanning Electron Microscopy. The Photonic Crystals-Dispersed Liquid Crystalline Metamaterials (PCs-DLCMs) have been investigated through polarized optical microscopy. The threshold voltage for the nematic LCs in a glass cell is also measured as a function of the frequency of the external electric field. [1] D. H. Werner, D.-H. Kwon, I. C. Khoo, A.V. Kildeshev and V.M. Shalaev, "Liquid crystal-clad near-infrared metamaterials with tunable negative-zero-positive refractive indices," Opt. Exp., vol. 15, pp. 3342-3347, 2007. [2] L. Petti, M. Rippa, J. Zhou, L. Manna and P. Mormile, "A Novel hybrid organic/inorganic photonic crystal slab showing a resonance action at the Band Edge", Nanotechnology, vol.22, 285307, 2011. [3] L. Petti, M. Rippa, J. Zhou, L. Manna, M. Zanella and P. Mormile, "Novel hybrid organic/inorganic 2D Quasiperiodic PC: from diffraction pattern to vertical light extraction", Nanoscale Research Letters, vol.6, 371, 2011.

In this paper a two-dimensional (2D) active nanograting photonic crystal (PC) which consists of air rods with a gammadion shape in a nanocomposite prepared by incorporating CdSe/CdS core/shell nanorods (NR) in a polymer is proposed and experimentally demonstrated. Scanning electron microscopy and spectra measurements are used to characterize the experimental structure. The vertical extraction of the light, by the coupling of the modes guided by the PQC slab to the free radiation via Bragg scattering, consists of a very narrow orange emission band at 610 nm with a full width at half-maximum (FWHM) of 14 nm. In this work the integration of CdSe/CdS core/shell nanorods in planar gammadion nanogratings is proposed as a new method to develop active devices based on organic photonics. The active nanocomposite containing colloidal semiconductor quantum rods of nanometer size scale is patterned to fabricate a 2D active PC. The 2D-PC pattern with gammadion rods with a side size of 550 nm and a depth of 350 nm has been uniformly formed by electron beam lithography in large areas of 900x900 µm2. The active gammadion-PC has been designed to match the properties of the active photonic material by changing the geometrical parameters of the structure to obtain, eventually, enhanced performances of the PC device. The possibility to pattern active materials open the route to the development of new high performing optical devices such as organic light-emitting diodes, ultra-low threshold lasers, sensors and non-linear devices.

Functional dyspepsia (FD) is a highly prevalent gastrointestinal disorder characterized by alterations in gastric motility. Yarrow (Achillea millefolium L., Fam Asteraceae) preparations are traditional remedies used to treat dyspeptic complaints. Herein, we investigated the effect of a standardized dry water extract obtained from A. millefolium flowering tops (AME) on gastric motility.The effect of AME on motility was evaluated on the resting tone of the isolated gastric antrum and on gastric emptying in vivo (phenol red meal method) both in control mice and in the model of cancer chemotherapy (cisplatin)-induced gastric abnormalities.The AME contracted mouse and human gastric strips and this action was unaffected by hexamethonium and tetrodotoxin, but strongly reduced by atropine. Among various chemical ingredients in yarrow, choline, but not the flavonoids rutin and apigenin, mimicked the action of AME. Furthermore, AME deprived of choline did not exert a contractile effect. In vivo, AME stimulated gastric emptying both in control and in cisplatin-treated mice, being more active in pathological states.It is concluded that (i) AME exerts a direct spasmogenic effect on gastric antrum; (ii) choline is the chemical ingredient responsible of such effect; (iii) the prokinetic effect of AME observed in vivo could provide the pharmacological basis underlying its traditional use in the treatment of dyspepsia.

Bromelain (BR) is a cysteine protease with inhibitory effects on intestinal secretion and inflammation. However, its effects on intestinal motility are largely unexplored. Thus, we investigated the effect of this plant-derived compound on intestinal contractility and transit in mice.Contractility in vitro was evaluated by stimulating the mouse isolated ileum, in an organ bath, with acetylcholine, barium chloride, or electrical field stimulation. Motility in vivo was measured by evaluating the distribution of an orally administered fluorescent marker along the small intestine. Transit was also evaluated in pathophysiologic states induced by the pro-inflammatory compound croton oil or by the diabetogenic agent streptozotocin.Bromelain inhibited the contractions induced by different spasmogenic compounds in the mouse ileum with similar potency. The antispasmodic effect was reduced or counteracted by the proteolytic enzyme inhibitor, gabexate (15 × 10(-6) mol L(-1) ), protease-activated receptor-2 (PAR-2) antagonist, N(1) -3-methylbutyryl-N(4) -6-aminohexanoyl-piperazine (10(-4) mol L(-1) ), phospholipase C (PLC) inhibitor, neomycin (3 × 10(-3) mol L(-1) ), and phosphodiesterase 4 (PDE4) inhibitor, rolipram (10(-6) mol L(-1) ). In vivo, BR preferentially inhibited motility in pathophysiologic states in a PAR-2-antagonist-sensitive manner.Our data suggest that BR inhibits intestinal motility - preferentially in pathophysiologic conditions - with a mechanism possibly involving membrane PAR-2 and PLC and PDE4 as intracellular signals. Bromelain could be a lead compound for the development of new drugs, able to normalize the intestinal motility in inflammation and diabetes.

Comunicazione poster

Nonalcoholic fatty liver disease (NAFLD) is becoming an increasing cause of chronic liver damage. The decision of start a medical treatment is based on the documented risk of progression to cirrhosis and liver cancer, when steatohepatitis (NASH) occurs. The therapy of this syndrome requires, as obviously, some considerations on the natural history of the condition, on the efficacy and safety of various therapeutic options, as well as on the costs. Treatment of patients with NAFLD has typically been focused on the management of associated conditions such as obesity, diabetes mellitus and hyperlipemia. Weight loss improves insulin sensitivity, and NASH may resolve with weight reduction. Insulin resistance seems to be the common denominator in many cases of NAFLD. Two classes of drugs have been shown to correct insulin resistance: biguanides (e.g., metformin) and thiazolidinediones (e.g., rosiglitazone and pioglitazone). The last two decades have witnessed a considerable progress in the understanding of the mechanisms respon-sible for the fibrogenic progression of chronic liver diseases. Several drugs believed to be hepatoprotective or antifibrotic agent as UDCA, betaine, vitamin E, lecithin, beta-carotene and selenium have been used in patients with NASH. Silybin is the main component of silymarin that is absorbed when linked whith a phytosome. This substance reduces in rats the lipid-peroxidation and the activaction of hepatic stellate cells. In humans, some non controlled data show that silybin is able to reduce insulin resistance, liver steatosis and plasma markers of liver fibrosis.

Hydroxytyrosol, a polyphenolic compound of chemical and biological interest, present as the main polyphenol in olive oil vegetation waters (VW), was purified from VW by means of a chromatographic method based on three steps. The compound was identified by UV, IR, H-1- and C-13-NMR and EIMS. Its preparation from a natural source, as VW, for laboratory use (analytical and biological studies, for example) is convenient from an economic and ecological point of view. The compound, labile in air and light, was transformed into the more stable triacetyl derivative, which was characterized by spectroscopic analysis, using the techniques mentioned above.

Gastrointestinal cancer is one of the leading causes of cancer mortality in the world. Therefore, numerous efforts are being made to find chemoprotective substances able to reduce its incidence. Amongst these, green tea, one of the most popular beverages world-wide, has been reported to provide protective effects against gastrointestinal cancer.To critically evaluate all epidemiological studies reporting an association between green tea consumption and a reduced risk of gastrointestinal cancer.Epidemiological studies of green tea consumption in relation to gastrointestinal cancer or preneoplastic lesions were identified through computerized literature searches using the following databases: Medline (Pubmed), Embase, Amed, CISCOM, Phytobase and Cochrane Library. Only epidemiological studies indicating the type of tea (green tea) and the site of either cancer or precancerous lesions (stomach or intestine) were included. No language restrictions were imposed.Twenty-one epidemiological investigations met our inclusion/exclusion criteria.These studies seemed to suggest a protective effect of green tea on adenomatous polyps and chronic atrophic gastritis formations. By contrast, there was no clear epidemiological evidence to support the suggestion that green tea plays a role in the prevention of stomach and intestinal cancer.

Three new pinolidoxins called epi-, dihydro-, and epoxy-pinolidoxin (2, 4, and 5, respectively)were isolated from Ascochyta pinodes grown on wheat, and theirs structures were determined using spectroscopic and chemical methods. They were characterized as 7-epi-, 5,6-dihydro-, and 5,6-epoxy-pinolidoxin, respectively. Assayed on pea and bean leaves, epipinolidoxin and dihydropinolidoxin caused necrotic lesions, whereas epoxypinolidoxin was inactive. Only epipinolidoxin and epoxypinolidoxin were active using the brine shrimp assay.

Two additional cytochalasins were isolated from liquid culture filtrates of Phoma exiqua var. heteromorpha together with some already known cytochalasins. The two new metabolites, named cytochalasin U and V, represent the first natural occurrence of a 25,26-dioxa[16] and 25-oxa[15]cytochalasan, respectively, both bearing a formyl group on the macrocyclic ring. Cytochalasins U and V showed respectively significant and weak activity in the brine shrimp assay.

We have evaluated the effect of cannabinoid drugs, administered intraperitoneally (i.p.) or intracerebroventricularly (i.c.v.) on upper gastrointestinal transit in control and in croton oil-treated mice. The cannabinoid agonists, WIN 55,212-2 (2-239 nmol mouse(-1)) and cannabinol (24-4027 nmol mouse(-1)), decreased while the CB(1) antagonist SR141716A (2-539 nmol mouse(-1)) increased transit in control mice. WIN 55,212-2, cannabinol and SR141716A had lower ED(50) values when administered i.c.v., than when administered i.p. The CB(2) antagonist SR144528 (52 nmol mouse(-1), i.p.) was without effect. During croton oil (0.01 ml mouse(-1), p.o.)-induced diarrhoea, the ED(50) values of i.p. -injected WIN 55,212-2 and cannabinol (but not SR141716A) were significantly decreased (compared to control mice). However, the ED(50) values of WIN 55,212-2 were similar after i.p. or i.c.v. administration. The inhibitory effects of WIN 55,212-2 and cannabinol were counteracted by SR141716A (16 nmol mouse(-1), i.p.) but not by SR144528 (52 nmol mouse(-1), i.p.) both in control and croton-oil treated mice. Ganglionic blockade with hexamethonium (69 nmol mouse(-1), i.p.) did not modify the inhibitory effect of i.p. -injected cannabinoid agonists either in control or in croton-oil treated mice. The lower ED(50) values of cannabinoid drugs after i.c.v. administration suggest a central (CB(1)) site of action. However, a peripheral site of action is suggested by the lack of effect of hexamethonium. In addition, croton oil-induced diarrhoea enhances the effect of cannabinoid agonists by a peripheral mechanism.

Putaminoxin and pinolidoxin, two structurally related nonenolides, isolated respectively from organic extracts of Phoma putaminum and Aschochyta pinodes cultures, together with some of their natural analogs and synthetic derivatives, were used in a structure-activity relationship study. Their phytotoxic, antifungal and zootoxic activities were assayed with the aim to find compounds with potential herbicidal properties. The strongest phytotoxic compounds proved to be putaminoxin and pinolidoxin, whose activity appeared to be correlated to the integrity of the nonenolide ring and to the presence of both the hydroxy groups and the unmodified propyl side chain. None of the assayed nonenolides showed antifungal activity, whereas pinolidoxin analogs and derivatives showed high to weak zootoxicity.

Two lower limb amputees with infected contralateral axillofemoral prosthetic grafts received preserved human arteries after removal of the infected materials. Both grafts grew organisms (Enterococcus species, plus Staphylococcus species in one). Long length arterial conduits were fashioned from freshly harvested (in one patient) and cryopreserved (in another one) cadaveric iliac and femoral arteries. One arterial homograft had ABO-compatibility with the recipient. No immunosuppressive drugs were administered after repeat arterial reconstructions. After 12 and 15 months both grafts are still patent, without parietal changes at ultrasonography; the patients have a viable remaining lower extremity and are free of symptoms or re-infection.

A case of acute iliofemoral artery thrombosis occurring 32 years after radiation therapy is reported. Radiological and MRI findings are described; the patient was successfully treated by intra-arterial thrombolysis and PTA-stent.

Blunt arterial injuries secondary to bone fractures are frequently associated with nerve, vein and soft tissue lesions. A delayed diagnosis or treatment is the main cause of high amputation rate. Thirty-four patients presenting acute arterial occlusion (15 cases), false aneurysms (13 cases) or AVFs (6 cases) of the extremity were identified between 1983 and 1995. To repair injured arteries, ligation (3 cases), patch angioplasty (6 cases), autogenous vein (15 patients) or PTFE (4 cases) interposition or bypass grafting were made. Percutaneous embolization by coils was performed in 3 AVFs of small limb arteries. Associated venous lesions were treated in 9 patients. External fixation of long bone fractures was made in 29 patients, before vascular reconstruction, to prevent further injury during orthopedic stabilization. Fasciotomies were made in 6 patients to treat compartmental hypertension. Early reexplorations were necessary to correct technical defects in 4 patients. Hyperbaric oxygen therapy was applied in 7 patients to control bacterial contamination and improve wound healing. Primary (2 cases) or secondary (3 cases) amputations were carried out in unsalvageable limbs. Nerve or extensive muscle damage caused poor functional outcome in 4 patients. A multidisciplinary diagnostic and management strategy is required to improve limb and patient survival.

Among complications of vascular access operations, symptomatic steal syndrome is uncommon, but may lead to ischemia of the hand. Between 1983 and 1995, 5 patients with hemodialysis fistulas presented rest pain of finger necrosis with a wrist-brachial index of 0.56 (range 0.35 to 0.63) improving to 0.96 (range 0.72 to 1.05) after digital pressure of the fistula. Ligation of distal radial artery was performed in 3 patients with side-to-end radiocephalic fistula, while basilic vein was distally ligated in a case of side-to-side brachiobasilic fistula. A vein "banding" procedure reduce fistula flow and improved distal perfusion in one patient, while a true venous aneurysm of the cephalic vein was treated by excision and replacement with a tapered PTFE graft. Hemodynamic assessment is required during surgical correction, but it may also be useful in pre- and intra-operative evaluation of patients undergoing therapeutical AVFs to prevent arterial insufficiency of the hand.

We review some chemical and biological aspects of toxic metabolites produced in vitro by phytopathogenic Ascochyta species, fungi having agrarian and toxicological importance. In particular, here the isolation of some known and new cytochalasins from A. heteromorpha and A. lathyri, four new nonenolides from A. pinodes and a new trisubstituted derivative of salycilic aldehyde from A. pisi are described. Furthermore, the identification of medicarpin, phytoalexin found in the chickpea seeds naturally infected by A. rabiei is also reported.

To evaluate dilatation of visceral arteries secondary to anomalies and collateral circulation.Case report.Department of Vascular Surgery, University Hospital.Two patients with secondary visceral aneurysms were reported. First patient (case 1) had a mid-aortic dysplastic syndrome with multiple aneurysms of the celiac trunk and right renal artery. Other patient (- case 2) presented an inferior pancreaticoduodenal artery aneurysm associated with proximal common hepatic artery occlusion.The case 1 was submitted to aortic and left renal artery angioplasty (PTFEE), while in the case 2 the resection of aneurysm was performed.Both patients had complete resolution of symptoms and are alive today.Clinical observations confirmed the development of visceral artery aneurysms secondary to arterial hypertension and collateral circulation.

Sir, Diet is thought to be one of the most important contributing factors to cancer risk (Bingham and Riboli, 2004). Among the dietary improvements that can reduce the risk of cancer, Stein and Colditz (2004) highlighted the promising relationship between prostate cancer and tomatoes intake. Here, we wish to draw attention to Allium vegetables (i.e. garlic and onion), which, on the basis of epidemiological studies, have been showing promising signs of possessing chemopreventive activity in patients with prostate cancer. Garlic (Allium sativum) and onion (Allium cepa) are among the oldest of all cultivated plants and now used as a food and for medical purpose (e.g. garlic for hypercholesterolaemia and hypertension) (Capasso et al, 2003). Site-specific, case–control studies and cohort studies suggest a preventive effect of Allium vegetables consumption against stomach, colorectal and prostate cancer, although evidence for a protective effect against cancer at other sites, including the breast, is still lacking (Ernst, 2000). Most notably, a population-based, case–control study, performed on 238 patients with prostate cancer and 471 male control subjects, investigated the association between intake of Allium vegetables and the risk of prostate cancer (Hsing et al, 2002). It was found that men in the category of highest intake of Allium vegetables (>10 g day−1) had a statistically significant lower risk of contracting prostate cancer than did those in the category of lowest intake (2.2 g day−1). The reduced risk of prostate cancer associated with Allium vegetables was independent of body size, intake of other foods and total calorie intake, and was more pronounced for men with localized than with advanced prostate cancer (Hsing et al, 2002). Experimental studies have shown that the chemopreventive activity of Allium vegetables is related to their content of organosulphur compounds (OSCs). Although how these compounds achieve chemoprevention is not fully understood, several modes of action have been proposed (Knowles and Milner, 2001; Griffiths et al, 2002; Rahman, 2003; Thomson and Ali, 2003). These include: (i) effect on drug metabolising enzymes (i.e. induction of phase II detoxification enzymes, including glutathione transferases, quinine reductase, epoxide hydrolase and glucuronosyl transferase, that inactivate toxic substances and facilitate their excretion); (ii) antioxidant activity (garlic preparations exhibit radical scavenging activity and decrease lipid peroxidation, which is relevant in the light of the observation that tumour promotion may involve oxygen radicals); (iii) tumour growth inhibition that has been documented in several carcinoma cell lines, including prostate carcinoma cells; (iv) induction of apoptosis, which coincides with an increase in the percentage of cells blocked in the G2/M phase of the cell cycle (possibly through a depression in p34cdc2 kinase); and (v) effective stimulation of the immune response (OSCs stimulates proliferation of lymphocytes and macrophage phagocytosis, induce the infiltration of macrophages and lymphocytes in transplanted tumours, induce splenic hypertrophy, stimulate release of interleukin-2, tumour necrosis factor-α and interferon-γ, enhance natural killer cell, killer cell and lymphokine-activated killer cell activity). In conclusion, promising data from clinical studies suggest that the regular consumption of garlic and onion may prevent prostate cancer. Allium-derived organosulphoric compounds may be responsible, at least in part, for the anticarcinogenic activity. The unique property of garlic and onion may be clinically important, because their daily intake for a prolonged period is expected to be free of risk.

When Escherichia coli 30 S ribosomal subunits are reacted with protein-protein bifunctional reagents, a number of protein pairs as well as aggregates containing three or more ribosomal proteins are formed. In the present study we have purified one of the protein pairs obtained by reaction of 30 S ribosomal subunits with either radioactive or nonradioactive dimethylsuberimidate. Following molecular weight determination and ammonolysis, the pair was shown to consist of ribosomal proteins S5 and S8. The "native" structure of the complex was surmised from its capacity to be reconstituted into a biologically active 30 S ribosomal subunit. From peptide maps and primary structure determination of various peptides it was demonstrated that the cross-linking bond between ribosomal proteins S5 and S8 involves primarily the residues Lys-93 of protein S8 and the COOH-terminal lysine (Lys-166) of ribosomal protein S5. This result is substantiated by the finding that a mutant carrying an altered S5 lacking the COOH-terminal lysine yields a greatly reduced amount of S5-S8 cross-link. In addition to the points of cross-linking it was found that Lys-30, Lys-68, and Lys-86 of S8 and Lys-5 of S5 react with dimethylsuberimidate, indicating that these residues are available for reaction and suggesting their topographical localization on the ribosomal surface.

This bibliography updates a previous one published in this journal (FSPB, 1976, 2, 191-206). The bibliography consists of 730 journal articles selected from 14 journals. The articles are arranged under 38 subject headings, with headings arranged alphabetically. and authors listed alphabetically under each heading. For ease of use the articles are numbered consecutively 1-730. The bibliography should be useful for courses and seminars emphasizing current literature.

This bibliography updates four previous ones which may be obtained from JSAS Catalog of Selected Documents in Psychology. The bibliography consists of 530 journal articles selected from 15 journals. The articles are arranged under 34 subject headings. Headings are arranged alphabetically; as are authors under each heading. For ease of use the articles are numbered consecutively 1-530. The number of articles under a heading varies from 2 to 44. The bibliography should be useful for courses and seminars emphasizing current literature.

The degree of macroscopic orientation of molten fibrous samples of nematic semiflexible polymers has been investigated by x-ray diffraction. Melting of highly oriented fibers is followed by a partial loss of macroscopic orientation but does not produce collapse of the fiber. The residual orientational order remains unaltered for a considerable time. The degree of orientational order depends on the temperature and undergoes odd-even fluctuations according to the parity of the number of carbon atoms contained in the flexible part of the monomer unit. Extrapolation of the order parameter to the isotropization temperature leads to a value of about 0.63 for even-type polymers and to about 0.47 for odd-type polymers. An intermediate value is found for a copolymer containing equal amounts of even and odd monomer units along the polymer chain.

Degre d'ordre caracterisant la phase nematique des homologues monomeres et dimeres des polyarylates-O(CH 2 ) n COO−C 6 H 4 −C(CH 3 )=HC−C 6 H 4 O

Intoxicated and nonintoxicated subjects competed in a reaction time situation against either a potentially threatening opponent or a nonthreatening opponent. The results indicated that the intoxicated subjects initiated higher levels of attack than the nonintoxicated subjects only in the threatening situation. It was concluded that aggression is not just a consequence of the pharmacological action of alcohol. Instead, alcohol-induced aggression appears to be a function of the interaction of alcohol consumption and the degree of threat or provocation inherent in a particular situation.