bluuebunny/crossref_metadata_2025 huggingface dataset:
Membrane Recognition by Vesicular Stomatitis Virus Involves Enthalpy-Driven Protein-Lipid Interactions
Authors: Carneiro Fabiana A. , Bianconi M. Lucia , Weissmüller Gilberto , Stauffer Fausto , Da Poian Andrea T.
Published: July 2002

Vesicular stomatitis virus (VSV) infection depends on the fusion of viral and cellular membranes, which is mediated by virus spike glycoprotein G at the acidic environment of the endosomal compartment. VSV G protein does not contain a hydrophobic amino acid sequence similar to the fusion peptides found among other viral glycoproteins, suggesting that membrane recognition occurs through an alternative mechanism. Here we studied the interaction between VSV G protein and liposomes of different phospholipid composition by force spectroscopy, isothermal titration calorimetry (ITC), and fluorescence spectroscopy. Force spectroscopy experiments revealed the requirement for negatively charged phospholipids for VSV binding to membranes, suggesting that this interaction is electrostatic in nature. In addition, ITC experiments showed that VSV binding to liposomes is an enthalpically driven process. Fluorescence data also showed the lack of VSV interaction with the vesicles as well as inhibition of VSV-induced membrane fusion at high ionic strength. Intrinsic fluorescence measurements showed that the extent of G protein conformational changes depends on the presence of phosphatidylserine (PS) on the target membrane. Although the increase in PS content did not change the binding profile, the rate of the fusion reaction was remarkably increased when the PS content was increased from 25 to 75%. On the basis of these data, we suggest that G protein binding to the target membrane essentially depends on electrostatic interactions, probably between positive charges on the protein surface and negatively charged phospholipids in the cellular membrane. In addition, the fusion is exothermic, indicating no entropic constraints to this process.
Respiratory Syncytial Virus (RSV) Nonstructural (NS) Proteins as Host Range Determinants: a Chimeric Bovine RSV with NS Genes from Human RSV Is Attenuated in Interferon-Competent Bovine Cells
Authors: Bossert Birgit , Conzelmann Karl-Klaus
Published: July 2002

Bovine respiratory syncytial virus (BRSV) escapes from cellular responses to alpha/beta interferon (IFN-α/β) by a concerted action of the two viral nonstructural proteins, NS1 and NS2. Here we show that the NS proteins of human RSV (HRSV) are also able to counteract IFN responses and that they have the capacity to protect replication of an unrelated rhabdovirus. Even combinations of BRSV and HRSV NS proteins showed a protective activity, suggesting common mechanisms and cellular targets of HRSV and BRSV NS proteins. Although able to cooperate, NS proteins from BRSV and HRSV showed differential protection capacity in cells from different hosts. A chimeric BRSV with HRSV NS genes (BRSV h1/2) was severely attenuated in bovine IFN competent MDBK and Klu cells, whereas it replicated like BRSV in IFN-incompetent Vero cells or in IFN-competent human HEp-2 cells. After challenge with exogenous IFN-α, BRSV h1/2 was better protected than wild-type BRSV in human HEp-2 cells. In contrast, in cells of bovine origin, BRSV h1/2 was much less resistant to exogenous IFN than wild-type BRSV. These data demonstrate that RSV NS1 and NS2 proteins are major determinants of host range. The differential IFN escape capacity of RSV NS proteins in cells from different hosts provides a basis for rational development of attenuated live RSV vaccines.
Synthesis of Porphyrin Heterobinuclear Ligands
Authors: Král Vladimír , Pánková Magdalena , Günterová Jana , Bělohradský Martin , Anzenbacher Pavel
Published: July 2002

A series of mono- or biscrown and azacrown ether porphyrin derivatives IIIb - IIIi, IVb and IVc were synthesized as model systems for cytochrome c oxidase. The arrangement of the porphyrin and the crown ether subunits and their spatial relation has been investigated by 1H NMR spectroscopy. The complexation properties of the synthesized ligands have also been studied.
Structure of the Products of Coupling of Substituted Ethylidene Malononitrile with Aryldiazonium Salts: Polarographic and Acid Dissociation Measurements
Authors: Helmy Ahlam M. A. , Morsi Mohamed A. , Elnagdi Mohamed H.
Published: July 2002

The structure of products of coupling of (α-ethoxycarbonyl-β-amino)ethylidene malononitrile (Ia) and (α-cyano-β-amino)ethylidene malononitrile (Ib) with aromatic diazonium salts could be established to be the corresponding hydrazone IIa (α-ethoxycarbonyl-α-phenylhydrazono-β-amino)ethylidene malononitrile and IIb (α-cyano-α-p-bromophenylhydrazono-β-amino)ethylidene malononitrile, via inspection of acid dissociation constants and the electrochemical behaviour of these products. IIa and IIb showed pKa ≈ 6 which is comparable to that of 2-phenylhydrazono-3-iminobutyronitrile (IV). The polarograms were found to be similar and consisted mainly of 4e reduction wave characteristic for hydrazones; also similar to the model hydrazone IV. The behaviour of 1-(p-methoxyphenyl)-3,5-dicyano-4-amino-6-iminopyridazine (IIIb) was found to be totally different. It did not reveal any potentiometrically traceable ionization step in aqueous media. Moreover its polarograms were totally different and consisted of two 2e waves. The more positive was E1/2-pH dependent and the more negative was E1/2-pH independent. Both waves were assigned for saturation of exocyclic and endocyclic C=N linkage. The mechanism of the electrode processes is also discussed.
On the Catalytic Effect of Dialkyl Derivatives of Thiourea on the Electrochemical Reduction of Zinc(II) Ions
Authors: Dalmata Grażyna
Published: July 2002

N,N'-Dimethyl-, N,N'-diethyl-, N,N'-diisopropyl- and N,N'-dibutylthiourea increase the rate of Zn(II) electroreduction in 1 M NaClO4. Increasing size of alkyl radical for the successive derivatives causes increase of their adsorption on mercury which, in turn, causes the increase of Zn(II) electroreduction rate. Electroreduction rate is also influenced by the change of molecule orientation on the electrode.
Enzymatically Catalyzed Generation of Electronically Excited States in a Synthetic Copolymer with a Schiff Base in Pendant Groups
Authors: Zoulík Robert , Pavlíček Zdeněk , Vohlídal Jiří , Šubr Vladimír
Published: July 2002

The copolymer of N-(2-hydroxypropyl)methacrylamide and N-[N-(N-methacryloylglycyl)glycyl]hexane- 1,6-diamine (17.6 mole %) was prepared as a model compound for investigation of the mechanism of enzymatically catalyzed generation of electronically excited states in proteins. The amino end groups of the copolymer side chains were transformed into a Schiff base by reaction with glycolaldehyde. The modified copolymer was characterized by its ultraviolet, visible and fluorescence spectra. The enzymatically catalyzed oxidation of the modified copolymer was carried out in a phosphate buffer at pH 7 using horseradish peroxidase as the enzyme. The generation of electronically excited states was demonstrated by chemiluminescence measurement and by a spectroscopic procedure based on transfer of the excitation energy to bilirubin.
Possibility of Anaesthetical Activity Prediction of N-(Pyrrolidinyl)ethyl Esters of Alkoxyphenylcarbamic Acids
Authors: Hatrík Štefan , Lehotay Jozef , Čižmárik Jozef
Published: July 2002

A back-propagation-type neural network consisting of three layers was used for predicting of surface and infiltration anaesthetical activity of pyrrolidinylethyl esters of 2- and 3-alkoxyphenylcarbamic acids. The prediction of local anaesthesia was based on the knowledge of this property for piperidinylethyl esters, piperidinylpropyl esters and azepanylethyl esters of 2- and 3-alkoxy- phenylcarbamic acids. The structural formulas of compounds pre-processed to the numerical input and RP-HPLC capacity factors (characterizing the lipophility of tested compounds) were used for generating inputs for the neural network. Anaesthetical activities of tested drugs calculated by neural network were in a good agreement with the experimentally measured data. Average error of predicted values ranges from 2% for the surface anaesthesia of pyrrolidinylethyl esters of 2-alkoxy- phenylcarbamic acids to 15% for the infiltration anaesthesia of pyrrolidinylethyl esters of 3-alkoxyphenylcarbamic acids.
Polarographic Determination of 6-β-D-Glucopyranosyloxy-7-hydroxycoumarin
Authors: Barek Jiří , Hrnčíř Roman , Moreira Josino C. , Zima Jiří
Published: July 2002

The polarographic behaviour was studied for 6-β-D-glucopyranosyloxy-7-hydroxycoumarin, a natural compound serving as an optical whitening agent. The substance can be quantitated by tast polarography, differential pulse polarography using a conventional dropping mercury electrode, and differential pulse polarography using a static mercury drop electrode over the regions of 20-1 000, 2-1 000, and 0.2-1 000 μmol l-1, respectively. The methods developed for the quantitation of the compound were applied to its direct determination in a raw product.
Spectral Investigation of Stability of the Peroxo Complexes M2[V2O2(O2)4H2O] . aq (M = N(CH3)4, N(C4H9)4) in Solutions
Authors: Schwendt Peter , Liščák Karol
Published: July 2002

Infrared spectra of solutions of M2[V2O2(O2)4H2O] . aq (M = N(CH3)4, N(C4H9)4) in heavy water and acetonitrile indicate that in concentrated solutions (c >= 0.5 mol dm-3) the asymmetric structure of the [V2O2(O2)4H2O]2- anion remains preserved for some time. Electronic spectra suggest that in more dilute solutions (c = 10-3-10-4 mol dm-3) of the M2[V2O2(O2)4H2O] . aq complexes in water and acetonitrile the dinuclear ion decomposes faster to [VO(O2)2H2O]-, followed by a relatively slow liberation of the peroxidic oxygen and formation of vanadate ions. The dinuclear complex is more stable in dilute chloroform solutions. The 51V NMR spectrum of an aqueous solution of [N(CH3)4]2[V2O2(O2)4H2O] (c = 1.3 mol dm-3) taken after a partial decomposition suggests the simultaneous presence of [V2O2(O2)4H2O]2-, [VO(O2)2H2O]-, (VnO3n)n- (n = 4, 5, 6), [HmV10O28](6-m)-, and other unidentified species.
1-Carba-arachno-pentaborane(10) Derivatives
Authors: Wrackmeyer Bernd , Schanz Hans-Jörg
Published: July 2002

The formation of organo substituted 1-carba-arachno-pentaborane(10) derivatives is shown to proceed in high yield via in situ generated 1,1,1-tris(diethylboryl)propane (2) from diethyl(propyn-1-yl)borane (1) by hydroboration with an excess of diethylborane (hydride bath). In the hydride bath, exchange reactions between 2 and other geminal bis(diethylboryl)alkanes take place until the carbaborane skeleton is formed. If tris(diethylboryl)methane is used under the same conditions, the corresponding 1-carba-arachno-pentaborane(10) derivatives 11 and 12 are formed in mixture with other unknown boranes or carboranes. 11B and 13C NMR data are presented to allow for straightforward identification of the 1-carba-arachno-pentaboranes(10).
Peptidomimetic Inhibitors of Extracellular Aspartic Proteinases of Candida albicans and Candida tropicalis
Authors: Brožková Kateřina , Křížová Ivana , Pavlíčková Libuše , Hradilek Martin , Fusek Martin , Ruml Tomáš , Souček Milan , Pichová Iva
Published: July 2002

In an attempt to develop effective inhibitors of Candida secreted aspartic proteinases, we have prepared a series of N-protected peptides varying in the type of scissile bond replacement, in the P and P' side chains as well as in the N- and C-terminal modifications. The compounds were tested in vitro with the chromogenic peptide substrate using purified secreted proteinases of C. albicans and C. tropicalis. Our results have confirmed that the binding of inhibitors and their effectiveness is influenced by a number of enzyme-inhibitor interactions. Moreover, factors like solvation/desolvation contribute to the optimal binding energy of the inhibitors.
Effects of Bridgehead Substituents on the Stability of the 1-Norbornyl Radical
Authors: Adcock William , Lunsmann Dieter
Published: July 2002

The electrochemical reductive cleavage of a series of 4-X-substituted bicyclo[2.2.1]heptan- 1-yl bromides and iodides (X = H, F, Cl, Br, I, SnMe3) was investigated by means of cyclic voltammetry. By application of the dissociative electron-transfer theory, the variations in the peak reduction potentials translate to values for the weakening of the C-Br and C-I bond dissociation energies (∆D) upon replacement of H by all the substituents (X). The ∆D values suggest significant through-space stabilizing interactions (homohyperconjugation) in the 4-X-substituted bicyclo[2.2.1]heptane radical species.
Reactions of Carbonyl Compounds in Basic Solutions. Part 34. The Mechanism of the Base-Catalysed Ring Fission of 2,3-Diphenylcycloprop-2-en-1-one
Authors: Bowden Keith , Burgess Emma J.
Published: July 2002

The rate coefficients for the base-catalysed ring fission of a series of 2-phenyl-3-(2-, 3- or 4-substituted phenyl)cycloprop-2-en-1-ones to give the corresponding (E)-2,3-diphenylacrylic acids have been determined in water at 30.0 °C, as well as for the unsubstituted compound at 40.0, 50.0 and 60.0 °C. The effects of meta- and para-substituents on the rates have been correlated using the Hammett equation to give a reaction constant, ρ, equal to ca 1.2 at 30 °C. For the unsubstituted compound, the activation parameters have been calculated and the kinetic solvent isotope effect has been studied. The effects of ortho-substituents on the rates appear to be mainly polar, rather than steric, in origin. The evidence indicates a mechanistic pathway which proceeds by addition of hydroxide anion to the ketone, which is rate-determining. The adduct suffers ring fission to give the final product via a carbanionic intermediate.
Porcine Liver Esterase-Catalyzed Hydrolysis of Methyl Tri-O-acetyl-β-D-arabinopyranoside, Methyl Tri-O-acetyl-β-D-ribopyranoside and Methyl Tri-O-acetyl-β-D-ribofuranoside
Authors: Moravcová Jitka , Kefurt Karel , Hladůvková Romana , Staněk Jan
Published: July 2002

Methyl 2,3,4-tri-O-acetyl-β-D-arabinopyranoside (1), methyl 2,3,4-tri-O-acetyl-β-D-ribopyranoside (2), and methyl 2,3,5-tri-O-acetyl-β-D-ribofuranoside (3) were deacetylated in porcine liver esterase-catalyzed reactions. Triacetate 1 gave methyl 3,4-di-O-acetyl-β-D-arabinopyranoside in 70% preparative yield while the regioselectivities found for the substrates 2 and 3 were substantially lower. Both the Michaelis constant and maximum rate were calculated for deacetylation of 1, 2, and 3. The results were interpreted using an active site model for the esterase proposed by Jones.
Cytostatic 6-Arylpurine Nucleosides II. Synthesis of Sugar-Modified Derivatives: 9-(2-Deoxy-β-D-erythro-pentofuranosyl)-, 9-(5-Deoxy-β-D-ribofuranosyl)- and 9-(2,3-Dihydroxypropyl)-6-phenylpurines
Authors: Hocek Michal , Holý Antonín , Votruba Ivan , Dvořáková Hana
Published: July 2002

9-(2-Deoxy-β-D-erythro-pentofuranosyl)-6-(4-substituted phenyl)purines, 9-(5-deoxy-β-D-ribofuranosyl)-6-(4-substituted phenyl)purines and 9-(2,3-dihydroxypropyl)-6-(4-substituted phenyl)purines were prepared by the Suzuki-Miyaura cross-coupling reactions of the corresponding protected 9-substituted 6-chloropurines with substituted phenylboronic acids followed by MeONa mediated deprotection. In contrast to the highly active 6-phenylpurine ribonucleosides, the title compounds did not show any considerable cytostatic activity.
Synthesis of Unsaturated Sulfur-Linked (1→4)-Disaccharides by Substitution of Tosyloxy Group in 1,6-Anhydro-3,4-dideoxy-2-O-tosyl-β-D-erythro-hex-3-enopyranose with 1-Thiohexopyranoses
Authors: Bartoš Petr , Černý Miloslav , Tišlerová Iva , Trnka Tomáš
Published: July 2002

A novel method for the synthesis of unsaturated sulfur-linked (1→4)-disaccharides is described. The starting 1,6-anhydro-3,4-dideoxy-2-O-tosyl-β-D-erythro-hex-3-enopyranose (3) was reacted with potassium salt of acetylated 1-thiohexopyranoses of D-gluco-, D-galacto-, and L-galacto-configuration to give acetylated β-glycopyranosyl-(1→4)-1,6-anhydro-2,3-dideoxy-4-thio-β-D-erythro-hex-2-enopyranoses 8-10. Their acid methanolysis under mild conditions afforded the corresponding methyl glycosides 11-13. The structure of new compounds was confirmed by 1H NMR and mass spectra data.
Spiro[4.5]deca-2,7-diene-1,6-dione and Spiro[5.5]undeca-2,8-diene-1,7-dione. Synthesis, Reductions and Palladium-Catalyzed Allylic Substitutions
Authors: Sirbu Doina , Sunel Valeriu
Published: July 2002

Spiro[4,5]deca-2,7-diene-1,6-dione (2a) and spiro[5,5]undeca-2,8-diene-1,7-dione (2b) were prepared by a direct synthesis starting from diethyl malonate. The two-step 1,2-reductions (NaBH4/CeCl3) of the diones gave cis/trans-diols, which could be easily transformed into diacetates. Both diacetates were subjected to Pd(0)-catalyzed allylic alkylations, in which the relative stereochemistry was retained.
Management of medical confidentiality in English professional football clubs: some ethical problems and issues
Authors: Waddington I , Roderick M
Published: July 2002

Objective: To examine the ways in which confidential matters are dealt with in the context of the relationship between the club doctor (or physiotherapist) and the player as patient in English professional football clubs.

Methods: Semistructured tape recorded interviews with 12 club doctors, 10 club physiotherapists, and 27 current and former players. A questionnaire was also sent to 90 club doctors; 58 were returned.

Results: There is among club doctors and physiotherapists no commonly held code of ethics governing how much and what kind of information about players may properly be passed on to managers; associated with this, there is considerable variation from one club to another in terms of the amount and kind of information passed on to managers. In some clubs, medical staff attempt to operate more or less on the basis of the rules governing confidentiality that apply in general practice, but in other clubs, medical staff are more ready to pass on personal information about players. In some situations, this raises serious ethical questions.

Conclusions: Guidelines dealing with confidentiality in practitioner-patient relationships in medical practice have long been available and have recently been restated, specifically in relation to the practice of sports medicine, by the British Olympic Association, the British Medical Association, and the Football Association. This is a welcome first step. However, if the guidelines are to have an impact on practice, detailed consideration needs to be given to ensuring their effective implementation; if this is to be achieved, consideration also needs to be given to identifying those aspects of the culture and organisation of professional football clubs that may hinder the full and effective implementation of those guidelines.
Genetics services in a social, ethical and policy context: a collaboration between consumers and providers: Table 1
Authors: Wertz Dorothy C , Gregg Robin
Published: July 2002

We report a unique, collaborative effort by users and providers of genetic services to arrive at outlines for optimal ethics and clinical practice. Using focus groups of consumers (users) and providers (held separately), a provider-consumer project team developed 1) a consumer wish list, 2) an experientially based ethical overview of situations arising in practice, and 3) detailed suggestions for consumer-provider interactions in clinical settings. Consumers were primarily interested in accurate information, respect for persons, a smoothly functioning team, with the consumer as an equal member of the team, family integrity, and providers who knew the limits of their knowledge and were willing to refer. “Non-directive” counselling and privacy were not major issues in consumer focus groups; some thought providers should openly state their own opinions. Providers had a rather different list of priorities.

Books and papers on clinical ethics usually originate from bioethicists and physicians. This pilot project is unique in including consumers and providers equally.
How to select publications on occupational health: the usefulness of Medline and the impact factor
Authors: Gehanno J F , Thirion B
Published: July 2002

OBJECTIVES

Publications in the field of occupational health appear in various journals, including those of other medical specialties. This complicates the follow up of literature for specialists in this field. On the basis of Medline and the impact factor, this diversity was assessed, and a cost effective method for selecting the most pertinent journals in the practice of occupational health was proposed.

METHODS

A Medline search identified all the articles published in 1998 with occupational diseases or occupational exposures as the main topic. These articles were classified based on the journals in which they appeared. The journals were then compared according to their subject area, the number of articles that were published in the fields studied, and their impact factor.

RESULTS

The search retrieved 2247 articles, published in 577 different journals in 1998. Each journal published between one and 105 articles during this period (mean 3.89). However, only 1.4% of the journals accounted for more than 25% of the total articles published. More than half of the articles were published in journals dealing with general practice or medical specialties other than occupational health. Only 66% of retrieved journals had an impact factor, and more than 80% of the articles were published in journals with an impact factor <2.

CONCLUSION

Simply following up occupational health journals is not sufficient to meet the requirements of the occupational health professional. Moreover, the use of the impact factor cannot be considered as a reliable research tool to assess follow up. Two lists of eight and 38 journals were thus set up. They permit a literature coverage of 27% and 52% respectively in the specific fields studied, and this seems to be the optimal compromise between time and literature covered. Lastly, practical procedures are suggested to follow up literature and obtain abstracts from selected journals on the internet.
Incidence of cancer among commercial airline pilots
Authors: Rafnsson Vilhjálmur , Hrafnkelsson Jón , Tulinius Hrafn
Published: July 2002

OBJECTIVES

To describe the cancer pattern in a cohort of commercial pilots by follow up through the Icelandic Cancer Registry.

METHODS

This is a retrospective cohort study of 458 pilots with emphasis on subcohort working for an airline operating on international routes. A computerised file of the cohort was record linked to the Cancer Registry by making use of personal identification numbers. Expected numbers of cancer cases were calculated on the basis of number of person-years and incidences of cancer at specific sites for men provided by the Cancer Registry. Numbers of separate analyses were made according to different exposure variables.

RESULTS

The standardised incidence ratio (SIR) for all cancers was 0.97 (95% confidence interval (95% CI) 0.62 to 1.46) in the total cohort and 1.16 (95% CI 0.70 to 1.81) among those operating on international routes. The SIR for malignant melanoma of the skin was 10.20, 95% CI 3.29 to 23.81 in the total cohort and 15.63, 95% CI 5.04 to 36.46 in the restricted cohort. Analyses according to number of block-hours and radiation dose showed that malignant melanomas were found in the subgroups with highest exposure estimates, the SIRs were 13.04 and 28.57 respectively. The SIR was 25.00 for malignant melanoma among those who had been flying over five time zones.

CONCLUSIONS

The study shows a high occurrence of malignant melanoma among pilots. It is open to discussion what role exposure of cosmic radiation, numbers of block-hours flown, or lifestyle factors—such as possible excessive sunbathing—play in the aetiology of cancer among pilots. This calls for further and more powerful studies. The excess of malignant melanoma among those flying over five time zones suggests that the importance of disturbance of the circadian rhythm should be taken into consideration in future studies.
A new cause of 'non-responsiveness' in coeliac disease?
Authors: Jennings J S R , Wyatt J I , Howdle P D
Published: July 2002

A 42 year old man presented with gluten-responsive coeliac disease and secondary pancreatic insufficiency. Subsequently his symptoms relapsed and repeat small intestinal biopsy showed villous atrophy and infiltration by leukaemic cells, despite continuation of a gluten-free diet. Serious causes of relapse and non-responsiveness in coeliac disease include enteropathy-associated T-cell lymphoma, ulcerative jejunitis and an end-stage hypoplastic mucosa. This is the first report of non-responsiveness due to infiltration by leukaemia.
Staphylococcus lugdunensisendocarditis
Authors: Farrag N , Lee P , Gunney R , Viagappan G M
Published: July 2002

A case of Staphylococcus lugdunensisendocarditis is presented with low back pain suggesting a secondary bone focus of infection. An umbilical skin lesion may have been an additional embolic phenomenon. The case highlights the aggressive nature of S lugdenensis endocarditis compared with other coagulase negative staphylococci and its association with native heart valves. In addition the importance of full identification of coagulase negative staphylococci isolated from patient samples in a case of suspected S lugdenensis infection is emphasised. Antibiotic treatment may be insufficient alone in the treatment of S lugdenensis endocarditis and early recourse to surgical intervention and valve replacement should therefore be considered.
Familiar drugs may prevent cancer
Authors: Sharma R A , Gescher A J , O'Byrne K J , Steward W P
Published: July 2002

Despite positive results in large scale chemoprevention trials, many physicians are unaware of the potential cancer preventive properties of drugs in common usage. The antioestrogen tamoxifen and the selective cyclo-oxygenase-2 inhibitor celecoxib have been licensed in the USA for the chemoprevention of breast and colorectal cancers respectively in selected high risk individuals. Similarly, folate and retinol have been shown to decrease the incidence of colorectal cancer and squamous cell carcinoma of the skin respectively in large scale intervention trials. Other retinoids have proved efficacious in the tertiary chemoprevention of cancers of the breast and head/neck. Epidemiological evidence also exists in favour of aspirin, non-steroidal anti-inflammatory drugs, and angiotensin converting enzyme inhibitors preventing certain cancers. Phytochemicals may represent less toxic alternatives to these agents. Although some of these drugs are available without prescription and most are not yet licensed for use in cancer chemoprevention, physicians and students of medicine should be aware of this accumulating evidence base. Practitioners should be amenable to patient referral to discuss complex issues such as risk estimation or potential benefit from intervention.
A new variant of Carney's triad: phaeochromocytoma and chondrosarcoma
Authors: Wahid S T , Jones R , Chawla S L , Connolly V M , Kelly W F , Bilous R W
Published: July 2002

A 61 year old hypertensive woman presented in 1986 with a right scapular chondrosarcoma. She developed type 1 diabetes mellitus in 1991 and suffered a stroke in 1991. Chest radiography showed pulmonary metastases in 1997. Further radiological staging detected a right sided phaeochromocytoma, which was subsequently removed in 1998. Before this, repeated urine estimations of vanillylmandelic acid had been normal. Her diabetes was cured by adrenalectomy. It is believed that the combination of phaeochromocytoma and extrapulmonary chondrosarcoma represents a new variant of Carney's triad.
Adrenal mass in a diabetic with hypergastrinaemia
Authors: Elasha H M S , Devendra D , Travis S , Wilkins D , Newman P , Wilkin T J
Published: July 2002

A 50 year old man originally presented in 1980 at the age of 31 with diarrhoea, weight loss, and abdominal pain. He was initially treated with steroids for presumed inflammatory bowel disease. About a month later he presented with severe abdominal pain, and a laparotomy revealed multiple jejunal perforations and a possible mass in the head of the pancreas. He made a good recovery during which time a nasogastric tube was in place for two weeks. A markedly raised serum gastrin level confirmed the diagnosis of Zohlinger-Ellison syndrome. Other gut hormone levels were normal. A parathyroid adenoma was suspected on account of raised calcium and parathyroid hormone levels.
Adult intussusception—an elusive diagnosis
Authors: Sotheran W J , Wise M H
Published: July 2002

An 81 year old woman presented, as an emergency, with a two day history of abdominal pain. The pain was intermittent and confined to the right upper quadrant. She had no other symptoms and normally enjoyed good health. Examination revealed tenderness in the right hypochondrium. Investigations revealed a mildly raised serum alkaline phosphatase. All other haematological and biochemical parameters were within normal limits. A provisional diagnosis of biliary colic was made.
A state of confusion
Authors: Sofat N , Higgens C S
Published: July 2002

A 66 year old right handed man was admitted via the accident and emergency department with confusion and weakness. His wife gave most of the history, saying he had not been able to express himself clearly for the last day and looked weak. He had no history of ischaemic heart disease, hypertension, hypercholesterolaemia, diabetes mellitus, or previous strokes. He smoked 10 cigarettes a day and drank alcohol only socially. He had been diagnosed with rheumatoid arthritis 20 years before. His drug history included diclofenac. On examination, the admitting doctor found that he had an expressive dysphasia and a right hemiparesis. He had a blood pressure of 140/70 mm Hg, pulse 80 beats/min and regular, both first and second heart sounds present with no added sounds and his chest was clear. His abdomen was soft and non-tender with no organomegaly. He had bilateral metacarpophalangeal joint swelling in his hands with ulnar deviation. On further neurological assessment he had an upper motor neurone right facial nerve palsy and the rest of his cranial nerves were normal. In his limbs, in addition to the right hemiparesis, he also had an ulnar nerve palsy in his left hand.
Fever with pain in bilateral shoulder joints
Authors: Kapoor S , Mehtani A , Batra S
Published: July 2002

A 15 year old male presented with a history of moderate fever with pain and limitation of movement of both shoulder joints for three weeks. On clinical examination the patient was febrile (100°F) and there was tenderness around the shoulder and proximal half of his upper arm on both sides. There was periarticular muscle spasm but no signs of any collection. There was restriction of both active and passive movements. There were no other significant findings.
Education and training in internal medicine in Europe
Authors: Hillen H F P
Published: July 2002

Sir William Osler was the Regius Professor of Medicine in Oxford at the end of World War I. In those days there was a great demand for postgraduate medical education. This was the motive for the foundation of the Fellowship of Postgraduate Medicine, under the presidency of William Osler. Osler himself had received his postgraduate education in Europe, from 1872 to 1874, during a two year sabbatical leave in teaching clinics in Germany. It was during this period that internal medicine was introduced as a specialty in the schools of medicine in Berlin, Göttingen, and Vienna.1 Postgraduate education in these clinics was directed at the practice of clinical medicine and was based on the latest advances in physiology, bacteriology, and pathology. The switch from mere observation to understanding had been made.
Visual disturbances and weight gain
Authors: Sharma S , Granot R , Thomas N , Wilcsek G A , White C , Fitzsimons R , Tidmarsh J , Tuch B E
Published: July 2002

A 51 year old man presented with a two year history of gradually deteriorating vision in his left eye, accompanied by 34 kg weight gain, easy bruising, and hypertension which was relatively resistant to conventional treatment. The patient denied any history of headaches. On examination, his general appearance was as shown (fig 1). On ocular examination his visual acuity was 6/6 in the right and 6/12 in the left eye. A left relative afferent pupillary defect was present and fundoscopically there was left optic nerve atrophy. Numerous investigations were performed, including Humphrey's field analysis (fig 2), and a cerebral magnetic resonance imaging (MRI) scan (fig 3). Eye positions on left lateral gaze were as shown (fig 4).
Diabetes and rapidly advancing pneumonia
Authors: Bhansali A , Suresh V , Chaudhry D , Vaiphei K , Dash R J , Kotwal N
Published: July 2002

A 20 year man, who was known to have had type 1 diabetes for the past one year, had high grade fever with chills and rigors, and cough with expectoration for 15 days. He was admitted with epigastric pain, vomiting, and tachypnoea after not taking insulin for four days before admission.
Autoamputation of the tongue
Authors: Pantanowitz L
Published: July 2002

Editor,—The case published by Patel et al recently of autoamputation of the tongue is an unusual life threatening incident worthy of reporting.1 However, the authors' statement that such an occurrence has never before been reported is inaccurate. At least five cases of autoamputation of the tongue have been reported in the English literature.2, 3, 4, 5, 6 I had previously been involved in reporting a case of tongue autoamputation in a mentally retarded patient after a flupenthixol injection.2 Self mutilation in this case was secondary to neuroleptic induced acute atypical orolingual dyskinesia. Bizarre and sporadic oral self injurious acts resulting in traumatic glossectomy have been known to occur among psychotic patients.3 Amputation of the tongue has also been documented after a motor vehicle accident, in which the unrestrained passenger was forced to bite down on his tongue with enough force to amputate a segment.4 Furthermore, self inflicted amputation of the tongue has been noted by other authors to cause macroglossia that compromised the upper airway, as well as result in life threatening secondary infections.5  6 Finally, serious oral self mutilation may be a rare pathological behavioural pattern that is observed in various neurological conditions such as encephalitis, coma, cerebral palsy, autism, mental retardation, seizures, as well as familial dysautonomia, Lesch-Nyhan syndrome, Tourette's syndrome, and the Cornelia de Lange syndrome.2 Clinicians should be aware of these possible underlying conditions when they are confronted with a patient presenting with such unusual self inflicted oral injuries.
Does history repeat itself in medicine?
Authors: Abdul-Aziz L A S
Published: July 2002

Editor,—I read with interest Dr Cook's “personal view”, on whether history repeats itself in medicine, and I think his article demonstrates his topic vividly. Another illustration is the attribution of the discovery of the pulmonary circulation uniquely to William Harvey (1578–1657).
Sleep deprivation and junior doctors’ performance and confidence
Authors: Lewis K E , Blagrove M , Ebden P
Published: July 2002

Purpose of study

To determine whether sleep deprivation affects not only junior doctors’ performance in answering medical questions but whether their ability to judge their own performance is also affected by lack of sleep.

Methods

A questionnaire based follow up study in two district general hospitals of the Carmarthenshire NHS Trust. Eleven house officers and 15 senior house officers (SHOs) within the medical directorate participating in the on-call rota were recruited between July 1999 and May 2000.

Results

SHOs answered significantly more questions correctly (p=0.04) and were more confident than house officers when they were either correct or incorrect (p<0.001). Length of unbroken or continuous sleep is associated with more correct answers (p=0.03) and higher energy (p=0.09) and confidence (p=0.07) scores self rated by the profile of mood states. Length of continuous sleep was not related to the appropriateness of confidence, as measured by the “within-subject confidence-accuracy correlation” (p=0.919).

Conclusions

SHOs performed better than house officers even allowing for sleep loss. Sleep deprivation had adverse effects on mood and performance but junior doctors can still monitor their performance and retain insight into their own ability when sleep deprived.
Integrated care pathways for vascular surgery: an analysis of the first 18 months
Authors: Sweeney A B , Flora H S , Chaloner E J , Buckland J , Morrice C , Barker S G E
Published: July 2002

Objectives

A review of the use of previously described integrated care pathways (ICPs) established for three elective vascular surgical procedures.

Design

A retrospective analysis of information gathered prospectively over an initial 18 month period of use of vascular surgical ICPs.

Subjects

Patients admitted to a single vascular unit for “open” repair of abdominal aortic aneurysm (AAA), carotid endarterectomy, or femoropopliteal bypass grafting.

Methods

An analysis of variance data, length of stay, and costings after the use of ICPs, compared with previous clinical practice.

Results

Variance data were gathered for each of the three procedures. Variances of medication prescribing and delays in discharge were common to all procedures. In particular: (i) gastrointestinal complications were more specific to AAA repair and (ii) wound drains were removed a day later than originally proposed after femoropopliteal bypass. Overall, improved efficiency due to use of ICPs reduced the length of stay for all procedures, which was reflected in a potential cost saving of some 25%.

Conclusion

There are clear benefits to the use of ICPs, resulting in more structured, efficient, and cost effective patient care. Recommended changes to current practice based on variance analysis will require continued audit to sustain this “evidence based” approach.
Comparison of the nicotine content of tobacco used in bidis and conventional cigarettes
Authors: Malson Jennifer L , Sims Kristi , Murty Ram , Pickworth Wallace B
Published: July 2002

OBJECTIVE

To compare the nicotine content of 12 unfiltered brands of bidi cigarettes (hand rolled cigarettes imported from India) with 8 popular brands of filtered and unfiltered US and conventional cigarettes from India.

MAIN OUTCOME MEASURES

Identical laboratory procedures were used to determine nicotine content (in duplicate) and physical characteristics.

RESULTS

The nicotine concentration in the tobacco of bidi cigarettes (21.2 mg/g) was significantly greater than the tobacco from the commercial filtered (16.3 mg/g) and unfiltered cigarettes (13.5 mg/g).

CONCLUSIONS

Bidi cigarettes contain higher concentrations of nicotine than conventional cigarettes. Therefore, it is logical to presume that bidi smokers are at risk of becoming nicotine dependent. These findings belie a popular belief among US teens that bidis are a safe alternative to commercial cigarettes.
Genome size and microsatellites: the effect of nuclear size on amplification potential
Authors: Garner Trenton WJ
Published: July 2002

Although the frequency of microsatellite DNA regions generally increases with increasing genome size, genome size has a negative effect on polymerase chain reaction (PCR) amplification. Thus, researchers developing sets of PCR primers, as is commonly done for microsatellite DNA regions, may encounter greater difficulty when working with species that have larger genomes. I investigated the effect of genome size on overall amplification success using data from nine different metazoan taxa. The proportion of primer sets that did not amplify PCR products was strongly and positively correlated with the haploid C value of the target species. Increasing genome size may affect amplification success negatively because of a decrease in target:nontarget DNA or by dilution of the available primer pool by nonspecific binding.Key words: microsatellites, genome size, amplification success.
Probabilistic slope stability analysis for practice
Authors: El-Ramly H , Morgenstern N R , Cruden D M
Published: July 2002

The impact of uncertainty on the reliability of slope design and performance assessment is often significant. Conventional slope practice based on the factor of safety cannot explicitly address uncertainty, thus compromising the adequacy of projections. Probabilistic techniques are rational means to quantify and incorporate uncertainty into slope analysis and design. A spreadsheet approach for probabilistic slope stability analysis is developed. The methodology is based on Monte Carlo simulation using the familiar and readily available software, Microsoft® Excel 97 and @Risk. The analysis accounts for the spatial variability of the input variables, the statistical uncertainty due to limited data, and biases in the empirical factors and correlations used. The approach is simple and can be applied in practice with little effort beyond that needed in a conventional analysis. The methodology is illustrated by a probabilistic slope analysis of the dykes of the James Bay hydroelectric project. The results are compared with those obtained using the first-order second-moment method, and the practical insights gained through the analysis are highlighted. The deficiencies of a simpler probabilistic analysis are illustrated. Key words: probabilistic analysis, slope stability, Monte Carlo simulation, spatial variability.
AN EXTENSION OF AN AUTOMATED TERMINATION METHOD OF RECURSIVE FUNCTIONS
Authors: KAMAREDDINE FAIROUZ , MONIN FRANCOIS
Published: July 2002

Inductive proofs are commonly used in automated deduction systems or functional programming, such as for instance the ProPre system, for establishing the termination of recursively defined functions. Such proofs deal with the structural orderings of the term algebras that define the domain of the functions. However there exists other interesting functions whose termination requires different underlying orderings. To treat a class of such functions that are not taken into account by systems such as ProPre, we develop termination properties that can be shown automatically. In contrast with the ProPre system that builds formal trees based on inductive proofs, we generate measures that satisfy an extended termination property and well-founded orderings which ensure the termination of the functions.
SMOOTHNESS OF N-BODY SCATTERING AMPLITUDES
Authors: SKIBSTED ERIK
Published: July 2002

We prove smoothness of the 2-cluster-2-cluster and 2-cluster-N-cluster scattering amplitudes under a general short range condition on the potential and under a discreteness assumption on the channel energies.
WEYL ALGEBRAS, FOURIER TRANSFORMATIONS AND INTEGRALS ON FINITE-DIMENSIONAL HOPF ALGEBRAS
Authors: NILL FLORIAN
Published: July 2002

The "Weyl algebras" [Formula: see text], σ, σ′ ∈ {+, –}, over a finite-dimensional Hopf algebra H are defined to be the abstract algebras generated by left or right (σ = ±) multiplication operators Qσ (ψ), ψ ∈ H, and left or right (σ′ = ±) translation operators Pσ′ (a), [Formula: see text] dual of H. It is shown that these algebras are all isomorphic to End (H). Fourier transformations are defined as intertwiners [Formula: see text] implementing a natural isomorphism [Formula: see text]. As a byproduct, this formalism provides a new proof of the invertibility of the antipode and the uniqueness (up to multiplication by a constant) of left and right integrals on finite-dimensional Hopf algebras. If H is a star Hopf algebra, the canonical representations of [Formula: see text] become star representation and Fourier transformation becomes an isometry w.r.t. a natural choice of nondegenerate hermitian forms on H and [Formula: see text]. Some comments on the relation with the C*-approach of Woronowicz and Podleś & Woronowicz are added.
BEYOND STRONG SUBADDITIVITY? IMPROVED BOUNDS ON THE CONTRACTION OF GENERALIZED RELATIVE ENTROPY
Authors: RUSKAI MARY BETH
Published: July 2002

New bounds are given on the contraction of certain generalized forms of the relative entropy of two positive semi-definite operators under completely positive mappings. In addition, several conjectures are presented, one of which would give a strengthening of strong subadditivity.

As an application of these bounds in the classical discrete case, a new proof of 2-point logarithmic Sobolev inequalities is presented in an Appendix.
MIND THE GAP
Authors: LITIM DANIEL F.
Published: July 2002

We discuss an optimisation criterion for the exact renormalisation group based on the inverse effective propagator, which displays a gap. We show that a simple extremisation of the gap stabilises the flow, leading to better convergence of approximate solutions towards the physical theory. This improves the reliability of truncations, most relevant for any high precision computation. These ideas are closely linked to the removal of a spurious scheme dependence and a minimum sensitivity condition. The issue of predictive power and a link to the Polchinski RG are discussed as well. We illustrate our findings by computing critical exponents for the Ising universality class.
From CKM Matrix to MNS Matrix: A Model Based on SUSY SO(10) × U(2)F Symmetry
Authors: Chen Mu-Chun , Mahanthappa K. T.
Published: July 2002

We construct a realistic model based on SUSY SO(10) with U(2) flavor symmetry. A set of symmetric mass textures give rise to very good predictions; 15 masses and 6 mixing angles are predicted by 11 parameters. Both the vacuum oscillation and LOW solutions are favored for the solar neutrino problem.
DOMAIN WALL RESISTIVITY BASED ON A LINEAR RESPONSE THEORY
Authors: TATARA GEN
Published: July 2002

The resistivity due to a domain wall in a ferromagnetic metal is calculated based on a linear response theory. The scattering by impurities is taken into account. The electron-wall interaction is derived from the exchange interaction between the conduction electron and the magnetization by use of a local gauge transformation in the spin space. This interaction is treated perturbatively to the second order. The classical (Boltzmann) contribution from the wall scattering turns out to be negligiblly small if the wall is thick compared with the fermi wavelength. In small contacts a large classical domain wall resistance is expected due to a thin wall trapped in the constriction. In the dirty case, where quantum coherence among electrons becomes important at low temperature, spin flip scattering caused by the wall results in dephasing and hence suppresses weak localization. Thus the quantum correction due to the wall can lead to a decrease of resistivity. This effect grows rapidly at low temperature where the wall becomes the dominant source of dephasing. Conductance change in the quantum region caused by the motion of the wall is also calculated.
MAGNETO-THERMAL INSTABILITIES IN AN ORGANIC SUPERCONDUCTOR
Authors: Mola M. M. , Hill S. , Qualls J. S. , Brooks J. S.
Published: July 2002

Angle and temperature dependent torque magnetization measurements are reported for the organic superconductor κ-( ET)2Cu(NCS)2 , at extremely low temperatures (~ Tc /103). Magneto-thermal instabilities are observed in the form of abrupt magnetization (flux) jumps. We carry out an analysis of the temperature and field orientation dependence of these flux jumps based on accepted models for layered type-II superconductors. Using a simple Bean model, we also find a critical current density of 4 × 108 A/m 2 from the remnant magnetization, in agreement with previous measurements.