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Background: Gallbladder cancer (GBC) is an aggressive, uncommon malignancy, with variation in operative approaches adopted across centres and few large-scale studies to guide practice. We aimed to identify the extent of heterogeneity in GBC internationally to better inform the need for future multicentre studies. Methods: A 34-question online survey was disseminated to members of the European-African Hepatopancreatobiliary Association (EAHPBA), American Hepatopancreatobiliary Association (AHPBA) and Asia–Pacific Hepatopancreatobiliary Association (A-PHPBA) regarding practices around diagnostic workup, operative approach, utilization of neoadjuvant and adjuvant therapies and surveillance strategies. Results: Two hundred and three surgeons responded from 51 countries. High liver resection volume units (>50 resections/year) organised HPB multidisciplinary team discussion of GBCs more commonly than those with low volumes (p < 0.0001). Management practices exhibited areas of heterogeneity, particularly around operative extent. Contrary to consensus guidelines, anatomical liver resections were favoured over non-anatomical resections for T3 tumours and above, lymphadenectomy extent was lower than recommended, and a minority of respondents still routinely excised the common bile duct or port sites. Conclusion: Our findings suggest some similarities in the management of GBC internationally, but also specific areas of practice which differed from published guidelines. Transcontinental collaborative studies on GBC are necessary to establish evidence-based practice to minimise variation and optimise outcomes.

Brick masonry is a multicomponent composite material, characterized by a marked inhomogeneity, a highly anisotropic behavior arising from the complex interactions between joints and bricks, and a considerable spatial variability of material properties, particularly relevant in the case of historical masonries. The focus of this paper is on the interdependence between the spatial variability of mechanical properties of joints and the overall homogenized response of a given volume element of masonry. It is assumed that mechanical properties of bed joints may vary according to a fixed probability distribution and correlation function and the mechanical response of the volume element is investigated in terms of the overall elastic stiffness. As confirmed by preliminary results, the spatial variability of the mechanical properties may affect the overall response of a masonry wall.

Background. Patients with prior colorectal cancer (CRC) are at slightly increased risk of metachronous colorectal neoplasms, therefore endoscopic surveillance is indicated. Current recommendations of repeating examinations at 1, 3 and 5 years after surgery, are not tailored according to risk stratification. Our aim was to find predictive factors of colorectal neoplasms to build a predictive model, to spare colonoscopies for lowrisk patients. Methods. Multicenter retrospective study including patients with colon carcinoma surgically resected from 2001 to 2008 (training cohort) and from 2009 to 2013 (validation cohort). A predictive model for neoplasms occurrence at second surveillance colonoscopy was developed and externally validated. Results. 396 and 131 patients were included in training and validation cohort respectively. Patients with >=1 adenoma at the 2nd surveillance colonoscopy were 113/396 (28.5%) and 21/131 (16.5%) in the two groups. In the validation cohort, 3 cancers were found. Four variables were associated with higher risk of metachronous colorectal adenomas at 2nd surveillance colonoscopy on multivariate analysis: age >65 years old, left colectomy, >=1 advanced adenoma at basal colonoscopy and >=1 adenoma at first surveillance colonoscopy (table 1). The predictive model showed fair discrimination, with an area under the ROC curve of 0.69 and 0.64, in training and validation cohort respectively. In validation group, If patients with a low-risk profile (i.e. none of the risk factors) skip the 2nd surveillance colonoscopy, 25/131 (19.1%) exams would be saved while missing 2/ 21 (9.5%) patients with 1 adenoma; no cancer would be missed. Conclusions We provided a risk-stratification tool for adenoma occurrence after colon surgery, which could prove cost-effective to select patients who could skip the second surveillance colonoscopy.

Aims. Patients with prior colorectal cancer (CRC) are at slightly increased risk of metachronous colorectal neoplasms, therefore endoscopic surveillance is indicated. Current recommendations of repeating examinations at 1, 3 and 5 years after surgery, are not tailored according to risk stratification. Our aim was to find predictive factors of colorectal neoplasms to build a predictive model, to spare colonoscopies for low-risk patients. Methods. Multicenter retrospective study including patients with colon carcinoma surgically resected from 2001 to 2008 (training cohort) and from 2009 to 2013 (validation cohort). A predictive model for neoplasms occurrence at second surveillance colonoscopy was developed and externally validated. Results 396 and 131 patients were included in training and validation cohort, respectively. Patients with ≥1 adenoma at 2nd surveillance colonoscopy were 113/396 (28.5%) and 21/131 (16.5%) in the two groups. In validation cohort, 3 cancers were found. Four variables identified the low-risk patient's profile of developing metachronous colorectal adenomas: age ≤65 years old, right colectomy, no advanced adenoma at basal colonoscopy and no adenoma at first surveillance colonoscopy. The predictive model showed fair discrimination, with an area under the ROC curve of 0.69 and 0.64, in training and validation cohort. In validation group, If patients with a low-risk profile skip the 2nd surveillance colonoscopy, 25/131 (19.1%) exams would be saved while missing 2/21 (9.5%) patients with ≥1 adenoma; no advanced adenoma nor cancer would be missed. Conclusions We provided a risk-stratification tool for adenoma occurrence after colon surgery, which could prove cost-effective to select patients who could skip the second surveillance colonoscopy.

Background Most current models for predicting survival after resection of colorectal liver metastasis include largest diameter and number of colorectal liver metastases as dichotomous variables, resulting in underestimation of the extent of risk variation and substantial loss of statistical power. The aim of this study was to develop and validate a new prognostic model for patients undergoing liver resection including largest diameter and number of colorectal liver metastases as continuous variables. Methods A prognostic model was developed using data from patients who underwent liver resection for colorectal liver metastases at MD Anderson Cancer Center and had RAS mutational data. A Cox proportional hazards model analysis was used to develop a model based on largest colorectal liver metastasis diameter and number of metastases as continuous variables. The model results were shown using contour plots, and validated externally in an international multi-institutional cohort. Results A total of 810 patients met the inclusion criteria. Largest colorectal liver metastasis diameter (hazard ratio (HR) 1.11, 95 per cent confidence interval 1.06 to 1.16; P Conclusion The contour prognostic model, based on diameter and number of lesions considered as continuous variables along with RAS mutation, predicts overall survival after resection of colorectal liver metastasis.

Src tyrosine kinase (TK), a redox-sensitive protein overexpressed in dystrophin-deficient muscles, can contribute to damaging signaling by phosphorylation and degradation of β-dystroglycan (β-DG). We performed a proof-of-concept preclinical study to validate this hypothesis and the benefit-safety ratio of a pharmacological inhibition of Src-TK in Duchenne muscular dystrophy (DMD). Src-TK inhibitors PP2 and dasatinib were administered for 5 weeks to treadmill-exercised mdx mice. The outcome was evaluated in vivo and ex vivo on functional, histological and biochemical disease-related parameters. Considering the importance to maintain a proper myogenic program, the potential cytotoxic effects of both compounds, as well as their cytoprotection against oxidative stress-induced damage, was also assessed in C2C12 cells. In line with the hypothesis, both compounds restored the level of β-DG and reduced its phosphorylated form without changing basal expression of genes of interest, corroborating a mechanism at post-translational level. The histological profile of gastrocnemius muscle was slightly improved as well as the level of plasma biomarkers. However, amelioration of in vivo and ex vivo functional parameters was modest, with PP2 being more effective than dasatinib. Both compounds reached appreciable levels in skeletal muscle and liver, supporting proper animal exposure. Dasatinib exerted a greater concentration-dependent cytotoxic effect on C2C12 cells than the more selective PP2, while being less protective against H2O2 cytotoxicity, even though at concentrations higher than those experienced during in vivo treatments. Our results support the interest of Src-TK as drug target in dystrophinopathies, although further studies are necessary to assess the therapeutic potential of inhibitors in DMD.

The inhibiting effect of dithiocarbamate (DTC) on bronze alloy TM 23 corrosion in acid medium was evaluated. Dithiocarbamate parabanic and DTC glycoluril were successfully synthesised from parabanic acid and glycoluril respectively. The compounds were characterised using elemental analysis and infrared spectroscopy. Quantum chemical calculations, weight loss test, polarisation curves and adsorption isotherms were performed. Dithiocarbamate parabanic is a more effective inhibitor of bronze alloy TM 23 than DTC glycoluril in an aqueous solution of nitric acid. Quantum chemical calculation indicated that these inhibitors interact with bronze alloy surface through dithiocarbamate groups. The two substances studied, DTC parabanic and DTC glycoluril, act as inhibitors cathode for bronze alloy TM 23 in 0·1 mol L−1 nitric acid. The adsorption of these inhibitors on bronze alloy TM 23 surface in acid media follows the Langmuir adsorption isotherm.

The full speciation of the vanadium(V) complexation systems with two aminohydroxamic acids, aspartic-β- and glutamic-γ-hydroxamic acid, has been determined using potentiometric and spectroscopic techniques. Formation constants were calculated in a systematic study at different ligand to metal molar ratios and the coordination types are proposed. An almost constant value of the 51V NMR signal in neutral medium can be attributed to two (1:1 and 1:2 metal to ligand ratios) similar structures, both of which can be either protonated or deprotonated. The two ligands have a carboxylic group in the structure and show comparable biological activities. In this work analogous complexation behavior at physiological conditions was found despite the presence of two or three methylenic groups between the amino and hydroxamate groups. The carboxylic groups are quite distant from the hydroxamic groups and are not involved directly in the coordination process. Therefore the coordination structures are related to that found in the vanadium(V)-β-alaninehydroxamic acid in which there is not a carboxylic group.

The full speciation of vanadium(V) complexation systems with glycinehydroxamic acid and three α-aminohydroxamic acids (α-alanine-, α-threonine- and α-lysine-) has been achieved using potentiometric and spectroscopic techniques. Formation constants were calculated in a systematic study at different concentrations and ligand-to-metal molar ratios. In each case, in a neutral medium, two complexes were identified with 1:1 and 1:2 metal-to-ligand ratios, both of which can either be protonated or deprotonated depending on the acidity or basicity of the medium. Structures are proposed based on 51V NMR results. The 1:1 complex, VO2L ( VO 2 + = dioxovanadium(V) ion and L− = α-aminohydroxamate ligand), has a distorted trigonal bipyramidal structure in neutral medium and it exists as VO 2 HL + in acidic and as VO 2 (OH)L - in basic medium. The 1:2 complex, VO 2 H 2 L 2 + , which is formed in neutral medium, has an octahedral structure and also exists as VO 2 H 3 L 2 2 + and VO 2 HL 2 , in acidic and basic media, respectively. In all cases, only the hydroxamate group appears to be coordinated to the VO 2 + group.

Em estudos ambientais, conhecer as formas químicas em que se encontram os elementos no solo e suas relações com os teores disponíveis são importantes para a previsão do comportamento no sistema solo-planta. Para avaliar a distribuição de cobre e de zinco em solos do Estado de Minas Gerais e sua relação com a disponibilidade, realizou-se o experimento com amostras de seis solos naturais em duas profundidades, as quais foram contaminadas com os elementos de interesse e submetidas ao processo de extraçãoseqüencial que separa os elementos nas frações trocável, oxidável, redutível e residual. O fracionamento forneceu importantesinformações em relação à interação do cobre e do zinco com os constituintes dos solos e da compartimentação dessas espécies entre asvárias frações dos solos. Verificou-se uma maior distribuição de zinco nas frações trocável e residual, enquanto que o cobre seassociou preferencialmente às formas químicas mais estáveis, ou seja, redutível e residual. As baixas recuperações de zinco eprincipalmente de cobre na fração trocável no Chernossolo Argilúvico Carbonático (solo 2) e no Cambissolo Háplico eutróficolatossólico (solo 3) corresponde a sistemas solo-metal com as maiores forças de retenção, estando os elementos nesses solos menosdisponíveis. A predominância de cobre e principalmente de zinco associados à fração trocável no Cambissolo Háplico Tb distróficotípico (solo 4) e no Neossolo Quartzarênico órtico latossólico (solo 6) evidencia a maior mobilidade e disponibilidade dos metais nossolos mais ácidos e arenosos comparado com os demais.Abstract In environmental studies, knowledge of thechemical forms of copper and zinc and the relationships with thelevels available, are important for predicting the elementsbehavior in the soil-plant system. To assess the distribution ofcopper and zinc in soils of Minas Gerais State and their relationswith their availability, an experiment was carried out on samplesfrom six natural soils at two depths. The soil samples wereincubated with the elements of interest and subjected tosequential extraction for separation of the elements in sixfractions defined operationally. The results showed that thetechnique provided valuable information regarding theinteraction of copper and zinc in soil and their speciation invarious fractions of soils. There was a larger distribution of zincin the exchangeable fraction and residual, while copper waspreferably associated to more stable chemical forms, that is,related to reducible and residual forms. The nearly nullextractions of copper and zinc from the soluble fraction and theexchangeable Argilúvico Chernosol (soil 2) and Tb eutrophicHaplic Cambisol (soil 3) systems correspond to the soil-metalsystem with the largest retention and lower availability of theelements in these soils. The predominance of copper and zincassociated mainly with the soluble and exchangeable fractions inCambisol (soil 4) and latosol orthic Quartzarenic Neosol (soil 6)showed increased mobility and availability of the metals in moreacidic and sandy soil when compared with the other soils.

Three new complexes of the general formula: [Ni(RSO 2 N CS 2 )(dppe)], where R = CH 3 ( 1 ), CH 3 CH 2 ( 2 ), 2-CH 3 C 6 H 4 ( 3 ) and dppe = 1,2-bis(diphenylphosphine)ethane, were obtained in crystalline form by the one-pot reaction of the appropriate potassium N -R-sulfonyldithiocarbimate: RSO 2 N CS 2 K 2 · 2H 2 O and 1,2-bis(diphenylphosphine)ethane with nickel(II) chloride hexahydrate in ethanol/water mixture. The complex 1 forms monoclinic crystals ( P2 1 /c ) with two molecules in the asymmetric unit ( Z = 8), while the crystals of the complexes 2 and 3 are orthorhombic, Pbca ( Z = 8) and P2 1 2 1 2 1 ( Z = 4) respectively, with one molecule in the asymmetric unit. All complexes present a distorted square-planar environment around the Ni atom. The elemental analyses and the IR, 1 H NMR, 13 C NMR and 31 P NMR spectra are consistent with the formation of the nickel(II) complexes with mixed ligands.

The compound 5-amino-2-mercapto-1,3,4-thiadiazole (AMT) is utilized in the conservation of archaeological and artistic bronze artifacts, for their protection and for the removal of corrosion products. Many authors have discussed the utility and efficacy of this, but few have studied the products resulting from the reaction of AMT with bronze or with the corrosion products of bronze; this leaves the restorer with many doubts concerning the acceptability of this method. This paper discusses the study of products obtained from the reaction of AMT with synthesized corrosion products of bronze (malachite, paratacamite and brochantite) and with the commercial bronze alloy TM 23 (Cu 72%, Pb 15%, Zn 8% and Sn 5%). It was found that the film obtained from the direct reaction of AMT with the bronze alloy can be AMT itself, or the metallic complex Cu(C2H2N3S2)2·H2O if AMT is applied in a solution of an oxidizing acid. These results are expected to be of value to conservation scientists and restorers/ conserv...

The corrosion products of a TM 23 bronze-leaded alloy (Cu 72%, Pb 15%, Zn 8% and Sn 5%) were obtained in a salt spray cabinet after exposition during 120 h and 1000 h. The products obtained were studied using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction. The major products of bronze-leaded corrosion were oxides and basic salts of Cu, CuCl2·3Cu(OH)2, and Pb, Pb(OH)Cl. The results can be attributed to a kinetic control of the corrosion reactions.

Background and purpose: Mexiletine (Mex), an orally effective antiarrhythmic agent used to treat ventricular arrhythmias, has also been found to be effective for myotonia and neuropathic pain. It is extensively metabolized in humans but little information exists about the pharmacodynamic properties of its metabolites.

The mercury(II) bis(dialkyldithiocarbamate) complexes, Hg(S 2 CN-R 2 ) 2 , in which R =ethyl, n -propyl, n -butyl and iso-butyl were characterized by TG, DSC, FTIR and elemental analysis. The TG curves presented two thermal decomposition stages; the first stage can be attributed to the partial decomposition of ligand and also to mercury sulfide decomposition. The second stage is representative for the decomposition of ligand fragments. The overlaid TG/DSC curves indicated that the decomposition of the complexes takes place the liquid phase. According to the isothermal kinetic data the phase-boundary controlled kinetic models describes the best the decomposition of complexes. The data obtained by the Ozawa method suggest the following stability order for the complexes: i Bu> n Pr> n Bu>Et.

Potassium N-R-sulfonyldithiocarbimates, K2(RSO2NCS2), react with K2[PtCl4] in water/methanol to yield complex anions bis(N-R-sulfonyldithiocarbimato)platinate(II), [Pt(RSO2NCS2)2]2−, (R=C6H5 (1) and 4-BrC6H4 (2)) which were isolated as their n-Bu4N+ salts.The single crystal X-ray analysis showed that (Bu4N)2[Pt(C6H5SO2NCS2)2] crystallizes in the triclinic space group P 1 , and (Bu4N)2[Pt(4-BrC6H4SO2NCS2)2] crystallizes in the monoclinic space group P21/c with disorder in the two chains of the two univalent Bu4N+ cation and 4-BrC6H4 groups of the anion. All complexes present a similarly distorted square-planar configuration due to the asymmetric bidentate chelation by two sulfur atoms. In both compounds the Pt atoms are in the crystallographic center of symmetry. Elemental analyses, IR spectra and electronic spectra were also consistent with the formation of platinum–sulfur diamagnetic square planar complexes. The 1H NMR, 13C NMR and 195Pt NMR spectra showed the expected signals for the n-Bu4N+ cation and the anionic complexes.

Potassium N-R-sulfonyldithiocarbimates, K2(RSO2N=CS2) (R = Me, Ph, 2-MeC6H4), react with Pd(OAc)2 to yield complex anions bis(N-R-sulfonyldithiocarbimato)palladate(II), [Pd(RSO2N=CS2)2]2−, which were isolated as their n-Bu4N+ salts. When the reaction was performed in the presence of Ph3P in a 2:1 ratio with respect to Pd(OAc)2, the N-R-sulfonyldithiocarbimatobis(triphenylphosphine)palladium(II) complexes were obtained. Elemental analyses, i.r. spectra and electronic spectra data were consistent with the formation of palladium–sulfur diamagnetic square planar complexes in the first case and mixed square planar complexes of palladium with Ph3P and dithiocarbimates in the second case. The 1H-n.m.r., 13C-n.m.r. and 31P-n.m.r. spectra showed the expected signals for the Bu4N+ cation, Ph3P and the dithiocarbimate moieties.

Three new complexes of the general formula: [Ni(PPh3)2(RSO2N � /CS2)] where R � /2-CH3C6H4 (1), 4-CH3C6H4 (2) and 4-BrC6H4 (3) were obtained in crystalline form by the reaction of the appropriate potassium N -R-sulfonyldithiocarbimates (K2(RSO2N � /CS2)) and triphenylphosphine with nickel(II) chloride in ethanol � /water. The 1 complex crystallizes in the centrosymmetric space group of the triclinic system with two molecules per unit cell, while 2 and 3 complexes crystallize in the Pbca space group of the orthorhombic system with eight molecules per unit cell. The X-ray single-crystal analysis showed that all complexes present a similarly distorted square-planar configuration around the nickel atom due to the steric effect of the triphenylphosphine ligands and the didendate chelation by the two sulfur atoms of the dithiocarbimate ligand. The IR and UV � /Vis spectral data are consistent with the formation of almost square-planar nickel complexes. The 1 H NMR, 13 C NMR, 31 P NMR spectra showed the expected signals for the triphenylphosphine and the dithiocarbimate moieties. # 2002 Elsevier Science Ltd. All rights reserved.

Maintaining postural stability is a complex process [1] involving the coordinated actions of biomechanical, sensory, motor, and central nervous system components. A relatively simple biomechanical definition for postural stability can be formulated in terms of the position of the body center of gravity relative to the base of support. The body movements used to maintain postural stability, however, are complex because of the number of joint systems and muscles involved. The center of gravity (CoG) is the point at which the whole weight of a body may be considered to act. In humans who are standing quietly and vertically erect, the CoG is located at the level of the hips and slightly forward of the ankle joints. CoG height is 0.5527 of total height. CoG and center of mass (CoM) are equivalent points in space when the gravitational field is uniform and gravity is the only force under consideration.

Dagli autori viene descritto un caso di un paziente di anni 64 (cardiopatico, epatopatico, broncopneumopatia ostruttiva) da circa 12 anni in trattamento neuropsichiatrico per sindrome depressiva con componente catatonica nel quale, dopo la comparsa di una sindrome da ipertensione endocranica, era stata posta diagnosi di craniofaringioma cistico soprasellare a sviluppo prevalente verso il terzo ventricolo. Il paziente, non potendo essere sottoposto ad intervento chirurgico a cielo aperto per le sue condizioni generali, è stato trattato per via neuroendoscopica. Si è proceduto alla perforazione ed allo svuotamento della cisti del craniofaringioma attraverso il forame di Monro di destra ed al posizionamento di catetere ventricolare nel residuo cistico per trattamento chemioterapico postoperatorio con bleomicina. L'intervento chirurgico non ha presentato complicanze ed il decorso postoperatorio è risultato essere regolare con una completa scomparsa dei segni di ipertensione endocranica presentati dal paziente. Dopo tre mesi dal trattamento è stato necessario sottoporre il paziente all'impianto di un sistema derivativo ventricolo peritoneale per il presentarsi di un idrocefalo ipertensivo triventricolare. Il follow up a 6 mesi risulta essere buono non presentando il paziente segni di recidiva della lesione cistica. Gli autori prendono in considerazione la possibilità di estendere questo tipo di trattamento a tutti quei casi in cui un craniofarigioma a prevalente componente cistica sia associato ad un coinvolgimento del sistema ventricolare.

Reaction of potassium N-R-Sulfonyldithiocarbimates, K2(RSO2N=CS2) (R=Me, Ph, 4-MeC6H4, 2-MeC6H4, 4-ClC6H4, 4-BrC6H4), with CoCl2·6H2O, yielded the complex CoIII anions [Co(RSO2N=CS2)3]3-, which were isolated as their Bu4N+ salts. Elemental analyses, i.r. spectra and u.v.-vis. data were consistent with the formation of cobalt-sulfur diamagnetic octahedral (D3) complexes. The 1H and 13C n.m.r. spectra showed the expected signals for the Bu4N+ cation and the dithiocarbimate moieties. The 1H n.m.r. integrations were consistent with a 3:1 cation:anion ratio.