bluuebunny/crossref_metadata_2025 huggingface dataset:
Self-assembly of bidentate ligands for combinatorial homogeneous catalysis based on an A-T base pair model
Authors: Breit Bernhard , Seiche Wolfgang
Published: March 2006

A new concept for generation of chelating ligand libraries for homogeneous metal complex catalysis based on self-assembly is presented. Thus, self-assembly of structurally simple monodentate ligands in order to give structurally more complex bidentate ligands is achieved employing hydrogen bonding. Based on this concept and on the 2-pyridone/hydroxypyridine tautomeric system, a new rhodium catalyst was identified which operated with excellent activity and regioselectivity upon hydroformylation of terminal alkenes. In order to generate defined unsymmetrical heterodimeric ligands, an A-T base pair analog-the aminopyridine/isoquinolone system-was developed which allows for complementary hydrogen bonding. Based on this platform, a 4 x 4 phosphine ligand library was screened in the course of the rhodium-catalyzed hydroformylation of 1-octene. A catalyst operating with outstanding activity and regioselectivity in favor of the linear aldehyde was discovered.
Hydrostannation of activated alkynes mediated by Stryker's reagent
Authors: Leung Lai To , Chiu Pauline
Published: March 2006

The treatment of activated alkynes with catalytic amounts of Stryker's reagent and tributylstannane resulted in hydrostannation. The reaction proceeds with high regioselectivity to produce α-stannated vinylstannanes exclusively.
First enantioselective one-pot, three-component imino Reformatsky reaction
Authors: Cozzi Pier Giorgio , Rivalta Eleonora
Published: March 2006

The Reformatsky reaction is the well-recognized carbon-carbon bond-forming reaction of α-halo esters with aldehydes or ketones in the presence of Zn metal to give β-hydroxy esters. Recently, it has been reported that Rh- and Ni-catalyzed Reformatsky reaction, in which R2Zn (R = Me, Et) acts as the Zn source, reacted smoothly with carbonyl compounds and imines. Taking advantage of N-methylephedrine as a cheap and recoverable chiral ligand, we have discovered the first homogeneous enantioselective Ni-catalyzed imino Reformatsky reaction. The process is a one-pot, three-component reaction, in which Me2Zn plays multiple roles as dehydrating agent, reductant, and coordinating metal. Broad scope, high enantiomeric excess, and a simple procedure are adding value to our findings.
New chiral tridentate ligands for asymmetric catalysis
Authors: Murtagh Kevin , Sweetman Brian A. , Guiry Patrick J.
Published: March 2006

The synthesis of new tridentate, isoquinoline-derived ligands, involving successive Suzuki cross-coupling reactions, is described. We were able to resolve 1-[3-(2-hydroxy-phenyl)-isoquinolin-1-yl]-naphthalen-2-ol via molecular complexation with N-benzylcinchonidinium chloride, whereas 1,3-bis(2-hydroxy-naphthalen-1-yl)-isoquinoline was resolved by chromatographic separation of its epimeric camphorsulfonates. Their barrier to rotation about the central biaryl axis was evaluated via racemization studies. Application of enantiopure 1,3-bis(2-hydroxynaphthalen-1-yl)-isoquinoline in the addition of diethylzinc to aldehydes proceeded in moderate yield but without asymmetric induction. A new tridentate ligand, 4-tert-butyl-2-chloro-6-[1-(2-hydroxymethyl-naphthalen-1-yl)-isoquinolin-3-yl]-phenol, was prepared in good yield and resolved by semipreparative high-performance liquid chromatography (HPLC). Its application in the addition of diethylzinc to a range of aromatic aldehydes proceeded in near perfect enantioselectivities at low ligand loadings of 1 mol %.
3-Aminopyrrolidine lithium amides as chiral ligands for alkyllithium derivatives: Synthesis, NMR analysis, and computational study of their mixed aggregates
Authors: Harrison-Marchand Anne , Valnot Jean-Yves , Corruble Aline , Duguet Nicolas , Oulyadi Hassan , Desjardins Stéphanie , Fressigné Catherine , Maddaluno Jacques
Published: March 2006

An overview of the role of 3-aminopyrrolidine lithium amides (3-APLi's) as chiral ligands for alkyllithiums (AlkLi's) is presented. Synthetic developments as well as NMR characterizations and computational interpretations have been simultaneously and complementarily conducted to improve the ligand design for a model reaction that is the condensation of AlkLi's on o-tolualdehyde, for which enantiomeric excesses up to 80 % were obtained. This study describes the whole chain going from the synthesis of the chiral 3-aminopyrrolidines (3-APs) (18 different 3-APs synthesized) to the characterization of the noncovalent mixed aggregates resulting from the interaction between the organolithium partners (3-APLi:AlkLi). Finally, the docking of the aldehyde on one lithium of the aggregate was analyzed by theoretical means on simplified models, in an attempt to understand the structure of the fully loaded pretransition complexes.
Torque control by metal-orbital interactions
Authors: Murakami Masahiro , Miyamoto Yasufumi , Hasegawa Munehiro , Usui Ippei , Matsuda Takanori
Published: March 2006

The silyl substituent of 3-silylcyclobutene prefers inward rotation rather than outward rotation during a thermal ring-opening reaction, giving the Z-isomer predominantly. This intriguing behavior was explained by assuming electron-accepting interactions between the low-lying σ*-orbital of the silicon-carbon linkage and the highest occupied molecular orbital (HOMO) of the opening cyclobutene system, which are possible only in the inward transition state. On the basis of this finding, a novel method for the stereoselective synthesis of functionalized 1,3-butadiene derivatives from cyclobutenones was developed. Boryl substituents exhibit even stronger preference for inward rotation than silyl substituents as a result of electron delocalization from the cyclobutene HOMO into the vacant p-orbital of boron at the inward transition state.
Alkenyl- and aryl[2-(hydroxymethyl)phenyl]dimethylsilanes: Tetraorganosilanes for the practical cross-coupling reaction
Authors: Nakao Yoshiaki , Sahoo Akhila K. , Imanaka Hidekazu , Yada Akira , Hiyama Tamejiro
Published: March 2006

Readily accessible and highly stable alkenyl- and aryl[2-(hydroxymethyl)phenyl]dimethylsilanes cross-couple with various aryl and alkenyl halides under mild reaction conditions employing K2CO3 as a base at 35-80 °C. The reaction tolerates a diverse range of functional groups including silyl protections. The silicon residue, cyclic silyl ether, is readily recovered and reused on a gram-scale synthesis. Intramolecular coordination of a proximal hydroxyl group is considered to efficiently form pentacoordinated silicates having a transferable group at an axial position.
Cycloruthenated compounds as efficient catalyst for asymmetric hydride transfer reaction
Authors: Sortais Jean-Baptiste , Barloy Laurent , Sirlin Claude , de Vries André H. M. , de Vries Johannes G. , Pfeffer Michel
Published: March 2006

Cycloruthenated complexes obtained by direct C-H activation of enantiopure aromatic primary and secondary amines are efficient catalysts in asymmetric hydride transfer reaction. Reduction of acetophenone has been achieved rapidly with enantiomeric excesses (ee's) ranging from 38 to 89 %. The importance of Ru-C bond in the catalytic efficiency is highlighted.
Connecting catalytic cycles by organometallic transformations in situ: Novel perspectives in the olefin metathesis field
Authors: Schmidt Bernd
Published: March 2006

Tandem sequences consisting of an olefin metathesis step and a subsequent non-metathesis reaction become accessible by organometallic transformations of the Ru-carbene species in situ. This contribution highlights some tandem sequences that rely on the conversion of the metathesis catalyst to Ru-hydrides, with special emphasis on the tandem ring-closing metathesis (RCM)-double-bond isomerization sequence.
Mucosal Immune Response in Cattle with Subclinical Johne's Disease
Authors: Weiss D. J. , Evanson O. A. , Souza C. D.
Published: March 2006

Mycobacterium avium subsp. paratuberculosis is the causative agent of Johne's disease, a chronic granulomatous enteritis of wild and domestic ruminants. During a long subclinical period, the organism persists in the intestine despite systemic cellular and humoral immune responses. To explore the mucosal immune response in Johne's disease, we isolated mononuclear leukocytes from the ileum of cows naturally infected with M. avium subsp. paratuberculosis and from cows that were not infected. We evaluated the immunophenotype of these cells and the proliferative responses after the addition of M. avium subsp. paratuberculosis sonicate or B-cell or T-cell mitogens. Although the percentage of T cells was increased in infected cows, these cells consisted mostly of memory (CD2+CD62L−) and regulatory (CD4+CD25+) T cells. Further evidence of immune hyporesponsiveness included a decrease in the percentage of T cells with an activated phenotype and a decrease in cells expressing major histocompatibility factor class II (MHC class II). Unlike the spleen, ileal lymphocytes from infected cows failed to proliferate in response to M. avium subsp. paratuberculosis sonicate. Additionally, ileal lymphocytes from infected cows proliferated poorly in response to concanavalin A and pokeweed mitogen, suggesting generalized T cell and B cell hyporesponsiveness. These results indicate that a state of tolerance may exist in the intestine of cows subclinically infected with M. avium subsp. paratuberculosis organisms in subclinically infected cows. This effect may be induced, at least in part, by proliferation of regulatory T cells that nonspecifically suppress mucosal immune responsiveness.
Pathogenesis of Newcastle Disease in Commercial and Specific Pathogen-free Turkeys Experimentally Infected with Isolates of Different Virulence
Authors: Piacenti A. M. , King D. J. , Seal B. S. , Zhang J. , Brown C. C.
Published: March 2006

The pathogenesis of five different Newcastle disease virus (NDV) isolates representing all pathotypes was examined in commercial and specific pathogen-free (SPF) turkeys. Experimentally-infected birds were monitored clinically and euthanatized, with subsequent tissue collection, for examination by histopathology, by immunohistochemistry for the presence of NDV nucleoprotein, and by in situ hybridization for the presence of replicating virus. Clinically, the lentogenic pathotype did not cause overt clinical signs in either commercial or SPF turkeys. Mesogenic viruses caused depression in some birds. Turkeys infected with velogenic neurotropic and velogenic viscerotropic isolates showed severe depression, and neurologic signs. Histologic appearances for all strains had many similarities to lesions observed in chickens inoculated with the various isolates; that is, lesions were present predominantly in lymphoid, intestinal, and central nervous tissues. However, in general, disease among turkeys was less severe than in chickens, and turkeys could be considered a subclinical carrier for some of the isolates.
Neuroblastoma with Neuronal Differentiation in the Spinal Cord in an Aberdeen Angus Heifer Calf
Authors: Steinberg H. , Peek S. F. , Nelson K. M.
Published: March 2006

A 5-month-old, female, Aberdeen Angus heifer presented to the veterinary medical teaching hospital for evaluation of slowly progressive hindlimb ataxia. The calf was clinically normal until 4 months of age, following routine pregnancy and delivery. Neurologic examination revealed marked symmetric spastic hindlimb paraparesis. Thoracolumbar radiographs and cerebrospinal fluid (CSF) analysis were unremarkable. A presumptive diagnosis of T3-L3 myelopathy was made, and neurologic status remained static for 3 months with broad-spectrum antibiotic and nonsteroidal anti-inflammatory therapy. Additional diagnostic tests were refused, and a necropsy was performed following euthanasia. A moderately well delineated, reddish-tan, soft mass 18 mm in diameter replaced 80% of the fourth lumbar spinal cord segment. Histologic examination revealed two distinct features: undifferentiated, primitive, polygonal-to-round cells with typical morphologic characteristics of primitive neuroectoderm; and interspersed areas containing myelinated axons and cells with neuronal differentiation. immunohistochemical examination confirmed the presence of primitive neuroepithelium and cells with neuronal differentiation.
Morphological and Immunohistochemical Features of Cryptosporidium andersoni in Cattle
Authors: Masuno K. , Yanai T. , Hirata A. , Yonemaru K. , Sakai H. , Satoh M. , Masegi T. , Nakai Y.
Published: March 2006

Light and electron microscopic features and immunohistochemical features of Cryptosporidium andersoni ( C. andersoni) and host reaction in the mucosa were studied. Although the affected cattle demonstrated no apparent clinical signs, a severe infection of C. andersoni was observed in the abomasum. C. andersoni were round in shape, measured 6-8 μm in size and were mainly observed to be freely located in the gastric pits, being attached in occasional cases to the surface of the abomasum epithelium. Frequent inflammatory cells had infiltrated the lamina propria of the affected mucosa, and frequent mitotic figures were observed in epithelial cells at the dilated isthmus. To access the cell kinetics, the number of epithelial cells infected with C. andersoni were counted and compared with noninfected cattle. The number of gastric pit cells in infected cattle was significantly higher than that in the controls. The number of proliferative cells determined by the Ki-67 antigen in C. andersoni infected cattle was also significantly higher than that in the controls. Transmission electron microscopy and scanning electron microscopy revealed that the morphology of the C. andersoni organism was common to those of other Cryptosporidium spp. immunohistochemically, several commercial antibodies against Cryptosporidium spp. showed positive reactions at the wall of these oocysts or parasitophorous vacuoles. This report is possibly the first to discuss the prominent hyperplasia of the abomasum mucosa, as well as morphologic features of C. andersoni in cattle.
Butyrylcholinesterase Activity, Cardiovascular Risk Factors, and Mortality in Middle-Aged and Elderly Men and Women in Jerusalem
Authors: Calderon-Margalit Ronit , Adler Bella , Abramson Joseph H , Gofin Jaime , Kark Jeremy D
Published: March 2006

Background: The association of butyrylcholinesterase (BuChE) with Alzheimer disease and the association of this disease with cardiovascular risk factors raise interest in the association of BuChE activity with cardiovascular risk factors and mortality.

Methods: A baseline cross-sectional study was conducted between 1985 and 1987, encompassing residents ≥50 years of age living in a Jewish neighborhood in western Jerusalem. Interviews were followed by examinations and nonfasting blood sampling (available for 1807 participants). Follow-up data to April 1996 on mortality and causes of death were obtained through record linkage with the Israeli Population Registry.

Results: BuChE activity was inversely related to age and was positively associated with serum concentrations of albumin (r = 0.35; P <0.001), cholesterol (r = 0.31; P <0.001), and triglycerides (r = 0.30; P <0.001). Enzyme activity was associated with measures of overweight, obesity, and body fat distribution (e.g., body mass index, r = 0.20; P <0.001). In multivariate analysis, the associations of enzyme activity with serum cholesterol, triglycerides, and albumin persisted strongly. After adjustment by Cox proportional hazards regression for other predictors of mortality in this population, individuals in the lowest quintile of BuChE activity had significantly higher mortality than those in the highest quintile [hazard ratios (95% confidence intervals): all-cause mortality, 1.62 (1.15–2.30); cardiovascular deaths, 1.79 (1.05–3.05)]. The association was attenuated by introduction of serum albumin into the models.

Conclusions: This is the first study to report on the association between BuChE and mortality. The relatively strong association of BuChE with serum lipid and albumin concentrations requires elucidation. Our results suggest that low BuChE activity may be a nonspecific risk factor for mortality in the elderly.
Fibroblast Growth Factor-1 and -2 Preserve Long-Term Repopulating Ability of Hematopoietic Stem Cells in Serum-Free Cultures
Authors: Yeoh Joyce S.G. , van Os Ronald , Weersing Ellen , Ausema Albertina , Dontje Bert , Vellenga Edo , de Haan Gerald
Published: March 2006

In this study, we demonstrate that extended culture of unfractionated mouse bone marrow (BM) cells, in serum-free medium, supplemented only with fibroblast growth factor (FGF)-1, FGF-2, or FGF-1 +2 preserves long-term repopulating hematopoietic stem cells (HSCs). Using competitive repopulation assays, high levels of stem cell activity were detectable at 1, 3, and 5 weeks after initiation of culture. FGFs as single growth factors failed to support cultures of highly purified Lin−Sca-1+c-Kit+(LSK) cells. However, cocultures of purified CD45.1 LSK cells with whole BM CD45.2 cells provided high levels of CD45.1 chimerism after transplant, showing that HSC activity originated from LSK cells. Subsequently, we tested the reconstituting potential of cells cultured in FGF-1 + 2 with the addition of early acting stimulatory molecules, stem cell factor +interleukin-11 + Flt3 ligand. The addition of these growth factors resulted in a strong mitogenic response, inducing rapid differentiation and thereby completely overriding FGF-dependent stem cell conservation. Importantly, although HSC activity is typically rapidly lost after short-term culture in vitro, our current protocol allows us to sustain stem cell repopulation potential for periods up to 5 weeks.
Aznalcóllar dam failure. Part 1: Field observations and material properties
Authors: Alonso E. E. , Gens A.
Published: March 2006

The paper describes the failure of Aznalcóllar dam, in southern Spain, in April 1998. The rockfill dam slid forward and released a flow of acid-saturated tailings. The geology and geomorphology of the site are described. The results of a detailed laboratory testing programme on the tailings material and on the overconsolidated high-plasticity foundation clay are given. Special attention is paid to the identification of cementation of the tailings and to the strength and consolidation properties of the foundation clay. Failure features are interpreted on the basis of the field evidence, taking into account the measured geotechnical properties of the materials involved.
Aznalcóllar dam failure. Part 2: Stability conditions and failure mechanism
Authors: Gens A. , Alonso E. E.
Published: March 2006

An analysis of the conditions that led to the failure of the Aznalcóllar dam is made in the paper. Pore water pressures prevailing in the foundation clay at the time of the failure have been established on the basis of piezometric observations made after the failure. A simplified consolidation analysis is first presented to interpret pore water pressure generation and dissipation and to evaluate the evolution of shear stresses along the potential failure plane. Both limit equilibrium and finite element analysis are used to back-analyse the failure and to derive representative strength parameters along the failure surface. Three-dimensional effects introduced by the layered nature of the foundation clay are then described. They provide an explanation for the location of the slide, which affected only the south-eastern portion of the embankment. The failure is examined in the final part of the paper from the perspective offered by the current knowledge of the strength behaviour of brittle clays. The significance of progressive failure is discussed, together with other factors that played a significant role in this case: the homogeneous nature and very low permeability of the foundation clay and the natural state of the clay, probably affected by some initial damage, which reduced the available strength along bedding planes.
Aznalcóllar dam failure. Part 3: Dynamics of the motion
Authors: Alonso E. E. , Gens A.
Published: March 2006

The motion of the Aznalcóllar dam slide, after the initiation of the failure, is examined in the paper. The moving mass remained essentially rigid, and Newton's second law provides the basic equation to determine the resulting dam displacement, velocity and acceleration. Resisting forces have been derived from a previous analysis of the conditions leading to failure. Pore water pressures induced by the forward motion of the dam are approximated as an undrained loading of the clay. Driving forces and their evolution in time derive from the liquefaction of tailings and the condition of constant volume of liquefied tailings pushing the moving dam forward. The stable ‘cliff’ left by the motion inside the tailings lagoon supports this hypothesis. The model is able to reproduce closely the distance travelled by the dam. It shows a low sensitivity with respect to reasonable changes of the main parameters. The model computes that the slide motion lasted about 15 s, and that the maximum acceleration experienced by the dam was 0·14g.
Autogenous deformations and viscoelasticity of UHPFRC in structures. Part II: numerical modelling
Authors: Habel K. , Charron J.-P. , Denarié E. , Brühwiler E.
Published: March 2006

Autogenous deformation is the main driving force for internal deformations in ultra-high performance fibre-reinforced concretes (UHPFRC). Experimental results of free and restrained shrinkage tests, described in part I of the current paper, are used to simulate the time-dependent behaviour of structural elements made of UHPFRC and normal-strength concrete (NSC). The validation of a numerical model is performed with experimental results of composite UHPFRC–concrete elements. The influence of the magnitude of UHPFRC autogenous shrinkage on deformations, stresses and crack formation in structural elements is determined in a parametric study. It is demonstrated that there are no excessive deformations and no crack formation in structural elements for magnitudes of autogenous shrinkage at 28 days below 1000 μm/m, that is, a value more than two times higher than that measured for the investigated UHPFRC.
Shear deformation in reinforced concrete beams with thin web
Authors: Debernardi P. G. , Taliano M.
Published: March 2006

In this paper the main results of an experimental campaign, carried out to analyse the shear deformation and interaction between moment and shear on the global and local deformations of reinforced concrete (RC) ‘I’ section simply supported beams with thin web, are discussed. A new theoretical model, which considers the lattice-like behaviour and applies the constitutive laws of the modified compressive field theory, is also proposed. The ‘concrete contribution’ of shear strength resistance is theoretically calculated. Experimental and theoretical results are then compared, showing the rotation of the principal compressive strain axis in the web. The influence of shear deformation on the deflection of the tested beams with thin web reaches 25% of the total deflection.
Ultrasonic inspection of concrete subjected to triaxial compressive loading history
Authors: Lu J. , Lin G. , Wang Z. , Xiao S.
Published: March 2006

An experimental study of the confined compression behaviour of concrete has been performed using 100 mm concrete cubes. The compressive strength, splitting tensile strength and ultrasonic velocity are measured before and after loading history, respectively. Based on the continuum damage mechanics theory, the reduction of compressive strength and splitting tensile strength denote the damage of concrete. The relationship between the damage and the decrease of ultrasonic velocity owing to triaxial loading history is investigated. According to the fitting of experimental data, the evolution equation of damage is obtained. The damage is found to be in a linear dependence relationship with the decrease of ultrasonic velocity. It is concluded that, being an important non-destructive detection method, ultrasonic inspection is convenient and applicable to the estimation of the damage of concrete under various loading patterns in engineering practice.
Evaluation of adverse effects of long-term orally administered carprofen in dogs
Authors: Raekallio Marja R. , Hielm-Björkman Anna K. , Kejonen Johanna , Salonen Hanna M. , Sankari Satu M.
Published: March 2006

Objective—To evaluate the adverse effects of carprofen in dogs after oral administration for 2 months.

Design—Prospective, randomized, blinded, placebo-controlled clinical trial.

Animals—22 dogs with osteoarthritis in the hip or elbow joint.

Procedure—13 dogs received orally administered carprofen daily for 2 months, and 9 dogs received a placebo for 2 months. Dogs were weighed, and serum and urine samples were collected before initiation of treatment and 4 and 8 weeks after initiation of treatment. Serum concentrations of total protein, albumin, urea, and creatinine and serum activities of alkaline phosphatase (ALP) and alanine aminotransferase (ALT) were measured. Urinary ALP-to-creatinine, γ-glutamyltransferase (GGT)-to-creatinine, and protein-to-creatinine ratios were calculated. Dogs were observed by owners for adverse effects.

Results—Serum protein and albumin concentrations were lower in treated dogs than in those that received placebo at 4 weeks, but not at 8 weeks. No changes were observed in serum urea or creatinine concentrations; ALP or ALT activity; or urinary ALP-to-creatinine, GGT-to-creatinine, or protein-to-creatinine ratios. Dogs' weights did not change. Severity of vomiting, diarrhea, and skin reactions did not differ between groups, but appetite was better in dogs receiving carprofen than in dogs in the placebo group.

Conclusions and Clinical Relevance—It is possible that the transient decreases in serum protein and albumin concentrations in dogs that received carprofen were caused by altered mucosal permeability of the gastrointestinal tract because no indications of renal or hepatic toxicity were observed. Carprofen appeared to be well tolerated by dogs after 2 months of administration.
Surgical approach to the coelomic cavity through the axillary and inguinal regions in sea turtles
Authors: Di Bello Antonio , Valastro Carmela , Staffieri Francesco
Published: March 2006

Objective—To describe a surgical approach to the coelomic cavity through the axillary and inguinal regions in sea turtles.

Design—Descriptive report.

Animals—9 loggerhead sea turtles (Caretta caretta) that had ingested fishhooks or monofilament fishing line.

Procedure—Turtles known to have ingested foreign bodies were anesthetized. For the extraction of fish-hooks located in the stomach, an approach to the coelomic cavity through the soft tissues of the left axillary region (along the cranial margin of the plastron) was made. For the removal of fishhooks and long fishing lines in other portions of the intestinal tract, an approach to the coelomic cavity was performed via the inguinal region. Foreign bodies were removed via gastrotomy or enterotomy.

Results—Of the 9 loggerhead turtles, 3 had a fish-hook in the stomach, 1 had a fishhook in the stomach and fishing line throughout the intestinal tract, 2 had a fishhook in the ileum and fishing line in the ileum and colon, and 3 had fishing line throughout the intestinal tract. Following surgery, 8 turtles recovered successfully; 1 turtle (in which an enterectomy was performed) died. After approximately 8 weeks, the surviving turtles were well enough to be released from captivity.

Conclusions and Clinical Relevance—Results indicated that an axillary approach to the coelomic cavity in sea turtles could be a useful alternative to plastron osteotomy. Moreover, the inguinal approach allows the exteriorization of the intestinal tract from jejunum to colon, which facilitates surgical removal of long linear foreign bodies ingested by turtles.
Extra-cellular chromate-reducing activity of the yeast cultures
Authors: Ksheminska Helena , Honchar Taras , Gayda Galyna , Gonchar Mykhailo
Published: March 2006

This paper reports on the experimental data supporting an essential role of extra-cellular reduction in chromate detoxification by baker’s and non-conventional yeasts. A decrease of chromate content in the yeast culture coincides with an increase of Cr(III) content in extra-cellular liquid. At these conditions, cell-bound chromium level was insignificant and a dominant part of extra-cellular Cr(III) species was detected in the reaction with chromazurol S only after mineralization of the cell-free samples. This phenomenon of chromium “disappearance” can be explained by the formation of Cr(III) stable complexes with extra-cellular yeast-secreted components which are “inaccessible” in the reaction with chromazurol S without mineralization. It was shown that increasing sucrose concentration in a growth medium resulted in an increase of chromate reduction. A strong inhibition of chromate reduction by 0.25 mM sodium azide, a respiration inhibitor and a protonophore, testifies that extra-cellular chromate detoxification depends on energetic status of the yeast cells. It was shown that Cr(III)-biochelates produced in extra-cellular medium are of a different chemical nature and can be separated into at least two components by ion-exchange chromatography on anionit Dowex 1x10. A total yield of the isolated Cr(III)-biocomplexes is approximately 65 % (from initial level of chromate) with a relative molar ratio 8:5.
Protein translocation through a tunnel induces changes in folding kinetics: A lattice model study
Authors: Contreras Martínez Lydia M. , Martínez‐Veracoechea Francisco J. , Pohkarel Prabhas , Stroock Abraham D. , Escobedo Fernando A. , DeLisa Matthew P.
Published: March 2006

Compaction of a nascent polypeptide chain inside the ribosomal exit tunnel, before it leaves the ribosome, has been proposed to accelerate the folding of newly synthesized proteins following their release from the ribosome. Thus, we used Kinetic Monte Carlo simulations of a minimalist on‐lattice model to explore the effect that polypeptide translocation through a variety of channels has on protein folding kinetics. Our results demonstrate that tunnel confinement promotes faster folding of a well‐designed protein relative to its folding in free space by displacing the unfolded state towards more compact structures that are closer to the transition state. Since the tunnel only forbids rarely visited, extended configurations, it has little effect on a “poorly designed” protein whose unfolded state is largely composed of low‐energy, compact, misfolded configurations. The beneficial effect of the tunnel depends on its width; for example, a too‐narrow tunnel enforces unfolded states with limited or no access to the transition state, while a too‐wide tunnel has no effect on the unfolded state entropy. We speculate that such effects are likely to play an important role in the folding of some proteins or protein domains in the cellular environment and might dictate whether a protein folds co‐translationally or post‐translationally. © 2006 Wiley Periodicals, Inc.
Effect of osmotic pressure on the production of retroviral vectors: Enhancement in vector stability
Authors: Coroadinha A.S. , Silva A.C. , Pires E. , Coelho A. , Alves P.M. , Carrondo M.J.T.
Published: March 2006

The use of Moloney murine leukaemia virus (MoMLV) derived retroviral vectors in gene therapy requires the production of high titer preparations. However, obtaining high titers of infective MoMLV retroviral vectors is difficult due to the vector inherent instability. In this work the effect of the cell culture medium osmotic pressure upon the virus stability was studied. The osmolality of standard medium was raised from 335 up to 500 mOsm/kg using either ionic (sodium chloride) or non‐ionic osmotic agents (sorbitol and fructose). It was observed that, independently of the osmotic agent used, the infectious vector inactivation rate was inversely correlated with the osmolality used in the production media; therefore, the use of high medium osmolalities enhanced vector stability. For production purposes a balance must be struck between cell yield, cell productivity and retroviral stability. From the conditions tested herein sorbitol addition, ensuring osmolalities between 410 and 450 mOsm/kg, yields the best production conditions; NaCl hampered the viral infectious production while fructose originates lower cell yields. Lipid extractions were performed for cholesterol and phospholipid analyses showing that more stable viral vectors had a 10% reduction in the cholesterol content. A similar reduction in cholesterol was observed in the producer cells. A detailed analysis of the major phospholipids composition, type and fatty acid content, by mass spectrometry did not show significant changes, confirming the decrease in the cholesterol to phospholipids ratio in the viral membrane as the major reason for the increased vector stability. © 2006 Wiley Periodicals, Inc.
Forensic psychiatric assessments in practice: a blind study of different forensic psychiatrists' assessments of the same cases
Authors: Belfrage Henrik , Lidberg Lars
Published: March 2006

Five senior psychiatrists from different forensic psychiatric settings in Sweden were given the task of assessing, independently of each other, material consisting of 40 randomly selected forensic psychiatric reports of non‐psychotic offenders, written previously by other forensic psychiatrists. The results show a remarkable degree of discrepancy in decision making among forensic psychiatrists. Overall, the differences appear to be random, but in some cases there were even negative correlations between assessments made by certain psychiatrists, that is, if one psychiatrist assessed an offender as in need of treatment, another one assessed him as not in need of treatment. Copyright © 1996 Whurr Publishers Ltd.
Psychosocial characteristics of young violent offenders: a comparative study
Authors: Katz Roger C. , Marquette Joe
Published: March 2006

When young people commit violent crimes such as homicide, the act is sometimes attributed to poorly controlled anger, rage or paranoid symptomatology. To test this assertion, we hypothesised that young men incarcerated for murder would show more anger, hostility and paranoid ideation, as well as increased levels of global psychopathology, than a cohort of non‐violent offenders and normal high school students. These predictions were not supported. Young murderers were indistinguishable from the two control groups on the MMPI‐A, the State‐Trait Anger Scale, and the SCL‐90‐R. Moreover, they showed no evidence of increased anger, paranoid features or global psychopathology relative to standardisation samples. Rather than being differentiated by personality characteristics, the data suggest that a history of gang membership and violent behaviour do a better job of discriminating between these groups. Copyright © 1996 Whurr Publishers Ltd.
Childhood experiences of patients with schizophrenia and a history of violence: a special hospital sample
Authors: Heads Tracey C. , Taylor Pamela J. , Leese Morven
Published: March 2006

Certain childhood experiences, including deprivation and/or abuse, have been shown to contribute to the development of delinquency and later criminality. Although specific illness factors influence violent or offending behaviour by people with schizophrenia, such childhood experiences may also be relevant. This study examined such factors in a sample of 102 patients with schizophrenia in a special hospital. Information was obtained from the hospital case notes. Experiences of a disordered family were found to be common, particularly for the women. Four main subgroups of patients were identified in terms of childhood experiences. Three groups, accounting for two‐thirds of the patients, had experiences of a range of problems in childhood before the manifest onset of schizophrenia. The first included patients with evidence of disorder of conduct but without remarkable environmental disadvantage (primary delinquency), the second those with multiple early environmental problems associated with a variety of personal conduct problems (secondary delinquency) and the third those with predominantly childhood neurotic problems in the absence of obvious family or environmental disturbance. Some 40% of the patients had ‘pure’ schizophrenia, its onset coming after an unremarkable childhood. Membership of one of the delinquency groups was associated with a significantly greater tendency to frequent, repeated violence. Group membership had no bearing on seriousness of violence, but there was a trend for people with ‘pure’ schizophrenia to have committed their index offence (usually the most serious) because of or mainly because of their psychotic symptoms. For patients with evidence of environmental disadvantage, conduct disorder or social difficulties as well as schizophrenia, there are likely to be complex interactions between such factors and symptoms of illness. For those with such experiences treatment is unlikely to be complete without attention to the impact and/or continuity of such problems. Copyright © 1997 Whurr Publishers Ltd.
Violence in schizophrenia and the syndrome of disorganisation
Authors: Baxter Richard
Published: March 2006

There is research evidence to support a significant and important if small association between schizophrenia and violence. Further it appears that some symptoms – delusions – may be particularly relevant. They do not, however, appear to account for all the excess of violence seen. The three‐syndrome model of schizophrenia (i.e. reality distortion, disorganisation and psychomotor poverty), is invoked to try and account for much of the remaining illness‐linked violence and to explore more explanatory possibilities. Whilst ‘impulsivity’ may be one common feature of neuroanatomical and biochemical theorising it is suggested that a principal feature of the disorganisation syndrome – expressive thought disorder – might hold an important place in clinical assessments if better tools were applied in its assessment. Copyright © 1997 Whurr Publishers Ltd.
Forensic psychiatry in Bulgaria
Authors: Dontschev Petko , Gordon Harvey
Published: March 2006

Forensic psychiatry in Bulgaria has been influenced by German, Russian and French concepts. Constrained by Soviet ideology, psychiatry in Bulgaria was affected by such political factors, but no real equivalent of the issue of Russian dissidents occurred. Concomitantly the positive Soviet orientation towards an effective system of community psychiatric care has been provided. With greater national independence in Eastern Europe, psychiatry in Bulgaria is now more amenable to liaison within the international community. Political and economic instability may hinder adequate development. Copyright © 1997 Whurr Publishers Ltd.
The need for longer term psychiatric care in medium or low security
Authors: Reed John
Published: March 2006

The provision of long‐term inpatient care for some mentally disordered patients is one objective of mental health policy. Because medium‐secure units were established in England with the objective of patients staying between 18 and 24 months, longer term care in secure conditions in England and Wales has mainly been provided by the high‐security (special) hospitals. There has been very limited provision specifically designed for patients needing longer term psychiatric care in security below the levels of the high‐security hospitals. This has led to patients being detained in inappropriate levels of security or in acute wards when rehabilitative care is more appropriate. A survey of all patients in all high‐ or medium‐secure units in England and Wales in December 1994 by questionnaire to their consultants showed that of some 1500 patients in the high‐security special hospitals, 490 would be more appropriately placed in longer term medium security and 150 in longer term low security. Of some 1250 patients in the current shorter stay medium‐secure units, 183 were considered to need longer term medium security and 278 longer term low security. To these must be added those in the general psychiatric service who need local/low secure care, perhaps 1300 in England. Overall there appears to be a need for some 750 beds in England and Wales offering long‐term medium security and 2000 beds offering longer term low security. Copyright © 1997 Whurr Publishers Ltd.
CNV predicts violent outcomes in patients released from special hospital
Authors: Howard Rick , Lumsden John
Published: March 2006

The ability of the Go/No Go contingent negative variation (CNV) to predict violent outcomes (violent re‐offending and suicide) was investigated in a sample of 44 male Broadmoor patients previously (in 1983) categorised as high or low risk on the basis of their Go/No Go CNV. An earlier (December 1990) follow‐up of the same sample had indicated that general criminal recidivism could be predicted by Go/No Go CNV (Howard & Lumsden, 1996). At 31 December 1994 a violent outcome had occurred in five of 21 high‐risk patients and in one of 23 low‐risk patients, yielding a predictive accuracy of 61.4% and a relative improvement over chance of 68%. High‐risk patients incurred five times as many violent reconvictions as did low‐risk patients. These results, whilst preliminary pending further follow‐up, offer the promise that the tragic consequences of releasing high‐risk mentally disordered offenders into the community might be prevented using a technique that is quick, cheap to administer and objective. Copyright © 1997 Whurr Publishers Ltd.
Reports of self‐injury in a maximum security hospital
Authors: Swinton Mark , Hopkins Richard , Swinton Jonathan
Published: March 2006

Previous studies have suggested that self‐injury rates vary during the day. This study is an analysis of all self‐injury incidents over an 18‐month period on the women's wards in a maximum security hospital. Self‐injury showed a marked peak late in the evening. Possible explanations are considered. Copyright © 1998 Whurr Publishers Ltd.
Adult criminality in previously hospitalized child psychiatric patients: with particular reference to girls and the use of ICD‐10 diagnoses
Authors: Wright Barry , McKenzie Immanuel , Stace Joanna , Berg Ian
Published: March 2006

A total of 171 children admitted to a psychiatric inpatient unit before age 13 were examined, between 1967 and 1980, using criminal offences between age 17 and 25 years as the main studied outcome. A retrospective cohort analytic design was employed using current classification systems. The children were followed up to the age of 25. About half of the males and a quarter of the females had received at least one standard list conviction by that time. Linear‐logistic modelling was used on boys and girls separately to explore childhood variables which were predictive of adult criminality. The important variables for boys were: large family size, parental criminality and a diagnosis of conduct disorder, and for girls were: having been in care prior to admission, parental criminality and a diagnosis of conduct disorder. The use of ICD‐10 diagnoses, the study of females and the investigation of a high‐risk population were particular features of this study. Copyright © 1998 Whurr Publishers Ltd.
Boys' lying and social adjustment in pre‐adolescence: teachers', peers' and self‐reports
Authors: Gervais Jean , Tremblay Richard E. , Héroux Diane
Published: March 2006

Boys' frequent lying was assessed twice over a 12‐month interval between 11 and 12 years of age, using teacher, peer and self‐reported data. Comparisons between the three sources of data revealed some concordance between peer and teacher reports on the frequency of lying, but a poor concordance between subjects' own and others' report on the frequency of lying. Behavioural characteristics of four groups of boys were compared: perceived and self‐reported liars; perceived and self‐reported non‐liars; not perceived and self‐reported liars; not perceived and self‐reported non‐liars. Boys perceived as liars were rated by peers as more aggressive, less likeable and more withdrawn. They were rated by teachers as fighting more, being more hyper‐active, oppositional and inattentive; the boys also reported more delinquent behaviours. Self‐reported liars were not perceived as having more adjustment problems but they reported more delinquent behaviours. Thus, results confirmed that preadolescent boys perceived as liars are also perceived by others and themselves as having more behaviour problems; however, the self‐reported liars are perceived as having behaviour problems only by themselves. These results indicated that the association between lying and social adjustment problems cannot be reduced to a negative reputation effect, but further studies were proposed to clarify the developmental links underlying the association. Copyright © 1998 Whurr Publishers Ltd.
Dramatherapy for mentally disordered offenders: changes in levels of anger
Authors: Reiss David , Quayle Marie , Brett Tim , Meux Clive
Published: March 2006

The aim of this study was to examine changes in levels of anger associated with a therapeutic theatre project. The population consisted of mentally disordered patients in a maximum security hospital, all of whom had a history of major violence. The subjects were being treated on a ward that specializes in psychotherapeutic interventions. Twelve young adult male patients, defined by structured interview for personality disorder and clinical diagnosis for mental illness, participated in a week‐long dramatherapy project. They were evaluated using self‐report questionnaires both before and after the week, as well as at three‐month follow‐up. Levels of anger significantly reduced from before to after the theatre week. This improvement was maintained at three‐month follow‐up. There was an associated increase in the frequency of attempts to control the expression of anger. It is concluded that a dramatherapy project within a psychotherapeutic environment may be an effective therapeutic modality for reducing anger levels in young mentally disordered offenders. Copyright © 1998 Whurr Publishers Ltd.
Long‐term medium‐security hospital units: a service gap of the 1990s?
Authors: Taylor Pamela J. , Maden Anthony , Jones Dilys
Published: March 2006

The majority of psychiatric patients, even those who also offend against the law, are likely to be served best by good community services but a few of them will need treatment in a secure hospital. Treatment in high security for patients from England and Wales is provided by three special hospitals. In the 1980s provision of medium‐secure hospital units began, but there is still a considerable shortfall of such beds. Data from a variety of settings suggest that the continuing gap in medium‐secure provision may be qualitative as well as quantitative. This paper considers the case for long‐term medium security, and the likely size and nature of demand. It would be misleading to assume that those with long‐term medium‐security needs constitute a homogeneous group. Some new facilities, probably built on to existing medium secure hospital units, are likely to be needed; if estimates of real need for high‐security places are correct, then some places already exist and are being used by default in the special hospitals. For some patients, notwithstanding the old image of special hospitals, these may be ideal placements if redesignated, even redesigned. A variety of provision and effective cooperation between purchasers and providers will be essential to satisfy real need and ensure that the number of patients needing secure accommodation remains more or less within present estimates. Copyright © 1996 Whurr Publishers Ltd.