bluuebunny/crossref_metadata_2025 huggingface dataset:
Epstein-Barr Virus Nuclear Antigen 3C Putative Repression Domain Mediates Coactivation of the LMP1 Promoter with EBNA-2
Authors: Lin Jeffrey , Johannsen Eric , Robertson Erle , Kieff Elliott
Published: July 2002

The Epstein-Barr virus (EBV) nuclear antigen 3C (EBNA-3C) regulates virus and cell genes and is essential for EBV-mediated transformation of primary B lymphocytes. EBNA-3C associates with the cellular DNA sequence-specific transcription factors RBP-Jκ and PU.1 and coactivates the EBV LMP1 promoter with EBNA-2 in BL2 and Raji cells under conditions of restrictive growth. We now find that EBNA-3C is similar to EBNA-LP in coactivating the LMP1 promoter with EBNA-2 in non-EBV-infected Burkitt lymphoma cells under conditions of maximal cell growth, whereas the EBV Cp promoter is repressed under the same conditions. EBNA-3A and EBNA-3B coactivation are at most 40% that of EBNA-3C. The RBP-Jκ binding sites of EBNA-2 and the LMP1 promoter are not required for EBNA-3C coactivation, whereas the PU.1 site in the LMP1 promoter is required for EBNA-2-mediated activation and EBNA-3C coactivation. EBNA-3C amino acids (aa) 365 to 545, including most of the previously identified repression domain (M. Bain, R. J. Watson, P. J. Farrell, and M. J. Allday, J. Virol. 70:2481–2489, 1996), are necessary and sufficient for coactivation with wild-type EBNA-2. EBNA-3C can also coactivate with the EBNA-2 acidic activating domain; this activation does not require aa 343 to 545. These data indicate that there are at least two mechanisms by which EBNA-3C coactivates the LMP1 promoter with EBNA-2. Of the proteins that interact with EBNA-3C in a yeast two-hybrid screen, only the ubiquitin-like proteins SUMO-1 and SUMO-3/hSMT3B map to aa 365 to 545, implicating these molecules in EBNA-3C coactivation. In addition, SUMO-1 associates at a high level with EBNA-3C in lymphoblasts. Promoter coactivation by EBNA-3C is likely to be important in ensuring adequate levels of LMP1, while inhibition of the EBNA-Cp promoter under the same conditions prevents uncontrolled up-regulation of EBNA expression from a positive-feedback loop.
The Central Conserved Cystine Noose of the Attachment G Protein of Human Respiratory Syncytial Virus Is Not Required for Efficient Viral Infection In Vitro or In Vivo
Authors: Teng Michael N. , Collins Peter L.
Published: July 2002

The G glycoprotein of human respiratory syncytial virus (RSV) was identified previously as the viral attachment protein. Although we and others recently showed that G is not essential for replication in vitro, it does affect the efficiency of replication in a cell type-dependent fashion and is required for efficient replication in vivo. The ectodomain of G is composed of two heavily glycosylated domains with mucin-like characteristics that are separated by a short central region that is relatively devoid of glycosylation sites. This central region contains a 13-amino acid segment that is conserved in the same form among RSV isolates and is overlapped by a second segment containing four cysteine residues whose spacings are conserved in the same form and which create a cystine noose. The conserved nature of the cystine noose and flanking 13-amino acid segment suggested that this region likely was important for attachment activity. To test this hypothesis, we constructed recombinant RSVs from which the region containing the cysteine residues was deleted together with part or all of the conserved 13-amino acid segment. Surprisingly, each deletion had little or no effect on the intracellular synthesis and processing of the G protein, the kinetics or efficiency of virus replication in vitro, or sensitivity to neutralization by soluble heparin in vitro. In addition, neither deletion had any discernible effect on the ability of RSV to infect the upper respiratory tract of mice and both resulted in a 3- to 10-fold reduction in the lower respiratory tract. Thus, although the G protein is necessary for efficient virus replication in vivo, this activity does not require the central conserved cystine noose region.
Bipartite Signal for Genomic RNA Dimerization in Moloney Murine Leukemia Virus
Authors: Ly Hinh , Parslow Tristram G.
Published: July 2002

Retroviral virions each contain two identical genomic RNA strands that are stably but noncovalently joined in parallel near their 5′ ends. For certain viruses, this dimerization has been shown to depend on a unique RNA stem-loop locus, called the dimer initiation site (DIS), that efficiently homodimerizes through a palindromic base sequence in its loop. Previous studies with Moloney murine leukemia virus (Mo-MuLV) identified two alternative DIS loci that can each independently support RNA dimerization in vitro but whose relative contributions are unknown. We now report that both of these loci contribute to the assembly of the Mo-MuLV dimer. Using targeted deletions, point mutagenesis, and antisense oligonucleotides, we found that each of the two stem-loops forms as predicted and contributes independently to dimerization in vitro through a mechanism involving autocomplementary interactions of its loop. Disruption of either DIS locus individually reduced both the yield and the thermal stability of the in vitro dimers, whereas disruption of both eliminated dimerization altogether. Similarly, the thermal stability of virion-derived dimers was impaired by deletion of both DIS elements, and point mutations in either element produced defects in viral replication that correlated with their effects on in vitro RNA dimerization. These findings support the view that in some retroviruses, dimer initiation and stability involve two or more closely linked DIS loci which together align the nascent dimer strands in parallel and in register.
Subcellular Localization and Topology of the p7 Polypeptide of Hepatitis C Virus
Authors: Carrère-Kremer Séverine , Montpellier-Pala Claire , Cocquerel Laurence , Wychowski Czeslaw , Penin François , Dubuisson Jean
Published: July 2002

Although biological and biochemical data have been accumulated on most hepatitis C virus proteins, the structure and function of the 63-amino-acid p7 polypeptide of this virus have never been investigated. In this work, sequence analyses predicted that p7 contains two transmembrane passages connected by a short hydrophilic segment. The C-terminal transmembrane domain of p7 was predicted to function as a signal sequence, which was confirmed experimentally by analyzing the translocation of a reporter glycoprotein fused at its C terminus. The p7 polypeptide was tagged either with the ectodomain of CD4 or with a Myc epitope to study its membrane integration, its subcellular localization, and its topology. Alkaline extraction studies confirmed that p7 is an integral membrane polypeptide. The CD4-p7 chimera was detected by immunofluorescence on the surface of nonpermeabilized cells, indicating that it is exported to the plasma membrane. However, pulse-chase analyses showed that only approximately 20% of endoglycosidase H-resistant CD4-p7 was detected after long chase times, suggesting that a large proportion of p7 stays in an early compartment of the secretory pathway. Finally, by inserting a Myc epitope in several positions of p7 and analyzing the accessibility of this epitope on the plasma membrane of HepG2 cells, we showed that p7 has a double membrane-spanning topology, with both its N and C termini oriented toward the extracellular environment. Altogether, these data indicate that p7 is a polytopic membrane protein that could have a functional role in several compartments of the secretory pathway.
Human Herpesvirus 8 Glycoprotein B (gB), gH, and gL Can Mediate Cell Fusion
Authors: Pertel Peter E.
Published: July 2002

Herpesvirus entry into cells and herpesvirus-induced cell fusion are related processes in that virus penetration proceeds by fusion of the viral envelope and cell membrane. To characterize the human herpesvirus 8 (HHV-8) glycoproteins that can mediate cell fusion, a luciferase reporter gene activation assay was used. Chinese hamster ovary (CHO) cells expressing the HHV-8 glycoproteins of interest along with a luciferase reporter gene under the control of the T7 promoter were cocultivated with human cells transfected with T7 RNA polymerase. Because HHV-8 glycoprotein B (gB) expressed in CHO cells localizes to the perinuclear region, a truncated form of gB (designated gBMUT) that lacks putative endocytosis signals was constructed by deletion of the distal 58 amino acids of the cytoplasmic tail. HHV-8 gBMUTwas expressed efficiently on the surface of CHO cells. HHV-8 gB, gH, and gL could mediate the fusion of CHO cells with two different human cell types, embryonic kidney cells and B lymphocytes. Substituting gBMUTfor gB significantly enhanced the fusion of CHO cells with human embryonic kidney cells but not B lymphocytes. Thus, two human cell types known to be susceptible to HHV-8 entry were also suitable targets for cell fusion induced by HHV-8 gB, gH, and gL. For human embryonic kidney cells and B cells at least, optimal fusion was noted with the expression of all three HHV-8 glycoproteins.
Antagonistic Analogs of Oxytocin with Substituted Phenylalanine or Tyrosine in Position 2
Authors: Ježek Rudolf , Žertová Miroslava , Slaninová Jiřina , Majer Pavel , Procházka Zdenko
Published: July 2002

Solid phase method on p-methylbenzhydrylamine resin was used for the synthesis of seven analogs of oxytocin with non-coded amino acids in position 2. [L-Phe(4-Me)2]oxytocin (I), [D-Phe(4-Me)2]oxytocin (II), [L-Phe(2-Me,4-Et)2]oxytocin (III), [D-Phe(2-Me,4-Et)2]oxytocin (IV), [D-Tyr(Me)2]oxytocin (V), [D-Tyr(Et)2]oxytocin (VI) and [L-Tyr(2-Me)2]oxytocin (VII) were synthesized. All analogs with D-stereoisomer of alkyl or alkoxy substituted phenylalanine possess uterus in vitro inhibiting activity. In the case of L-stereoisomers the structure activity relationship is more complicated. As far as the pressor activity is concerned, the analogs have either very low agonistic activity or low degree of antagonism.
Effect of Temperature on the Solubility Diagrams of Ammonium Bromcarnallite
Authors: Christov Christomir , Balarew Christo
Published: July 2002

The solubility isotherms of the systems NH4Br - MgBr2 - H2O and NH4Br . MgBr2 . 6 H2O - MgBr2 - H2O have been investigated by the physicochemical analysis method at 75 °C and formation of carnallite type double salt is established. The effect of temperature on the crystallization conditions is discussed.
Quaternary Isoquinoline Alkaloids and Some Diterpenoid Alkaloids in Plants of the Czech Republic
Authors: Slavík Jiří , Slavíková Leonora
Published: July 2002

The root bark and the stem bark of Berberis vulgaris L. (16.2 and 6.0 wt.% of total alkaloids) yielded berberine (IIa), magnoflorine (I) and jatrorrhizine (IIc) as major quaternary alkaloids along with small quantities of palmatine (IIb) and alkaloid BV 1. Oxyacanthine and berbamine were separated from the non-quaternary fraction. Isocorydine was the main alkaloid in the leaves. Magnoflorine was also isolated from the stem bark and twigs of Magnolia x soulangeana SOULANGE-BODIN, M. x speciosa REICHENB., and M. kobus DC., from the tubers of Aconitum firmum REICHENB., and from the roots of Clematis recta L. (iodide, 0.52 wt.%). Small amounts of magnoflorine were detected in Magnolia x soulangeana cv. Alexandrina and cv. Norbertiana, in Aconitum callibotryon REICHENB., in the roots of A. vulparia REINCHENB., and in Actaea spicata L. In Aconitum firmum, A. callibotryon, A. vulparia, Clematis recta and Actaea spicata, the presence of corytuberine was also demonstrated. From the tubers of Aconitum firmum (0.97 wt.% of total bases), hypaconitine (IIIb) was separated as the major alkaloid accompanied with small amounts of aconitine (IIIa), mesaconitine (IIIc), and deoxyaconitine (IIId). In A. callibotryon, mesaconitine and an unidentified alkaloid were found as the dominant basic components together with small quantities of aconitine and hypaconitine.
The 1- and 2-Naphthylalanine Analogs of Oxytocin and Vasopressin
Authors: Procházka Zdenko , Slaninová Jiřina
Published: July 2002

Solid phase technique on p-methylbenzhydrylamine resin was used for the synthesis of four analogs of oxytocin and four analogs of vasopressin with the non-coded amino acids L- or D- and 1- or 2-naphthylalanine and D-homoarginine. [L-1-Nal2]oxytocin, [D-1-Nal2]oxytocin, [L-2-Nal2]oxytocin, [D-2-Nal2]oxytocin, [L-1-Nal2, D-Har8]vasopressin, [D-1-Nal2, D-Har8]vasopressin, [L-2-Nal2, D-Har8]vasopressin and [D-2-Nal2, D-Har8]vasopressin were synthesized. All eight analogs were found to be uterotonic inhibitors in vitro and in vivo. Analogs with 2-naphthylalanine are stronger inhibitors, particularly in the vasopressin series than the analogs with 1-naphthylalanine. Analogs with 1-naphthylalanine have no activity in the pressor test, analogs with 2-naphthylalanine are weak pressor inhibitors.
Dimethyl Sulfate Induced Nucleophilic Substitution of the [Bis(1,2-dicarbollido)-3-cobalt(1-)]ate Ion. Syntheses, Properties and Structures of Its 8,8'-μ-Sulfato, 8-Phenyland 8-Dioxane Derivatives
Authors: Plešek Jaromír , Heřmánek Stanislav , Franken Andreas , Císařová Ivana , Nachtigal Christiane
Published: July 2002

Syntheses and structures of [8,8'-μ-(OSO2O)(1,2-C2B9H10)2-3-Co]-and [(8-Ph-1,2-C2B9H10)-3-Co-(1',2'-C2B9H11]- ions and of [(8-dioxane-1,2-C2B9H10)-3-Co-(1',2'-C2B9H11)] zwitterion are described. All compounds result on dimethyl sulfate induced nucleophilic B-substitution of the parent cobalta-carborane sandwich ion under acid catalysis. A general mechanism is proposed. Constitutions of all compounds are inferred from the mass and multinuclear NMR spectroscopy and all structures are established by X-ray diffraction. Selected NMR and X-ray data are presented.
A New Pharmacophore of Potential Antimycobacterial Activity: The Disulfide Group in the Ring of Alicyclic Compounds
Authors: Stachel Hans-Dietrich , Odlerová Želmíra , Waisser Karel
Published: July 2002

A series of thirty 2,3-dithiabicyclo[3.3.0]octa-4,8-diene derivatives was examined for antimycobacterial activity against Mycobacterium tuberculosis, M. kansasii, M. avium, and M. fortuitum. The structure-activity relationships were analysed by Free-Wilson method. The authors consider the disulfide moiety to be the pharmacophore of antimycobacterial activity. To verify the idea, several other monocyclic sulfides, 3,4-dihydro-1,2-dithiolane derivatives, were also evaluated.
Synthesis and Characterization of (μ-Oxalato)nickel(II), Copper(II) and Zinc(II) Complexes with Chelating Polyamines
Authors: Smékal Zdeněk , Trávníček Zdeněk , Nádvorník Milan , Šindelář Zdeněk , Klička Roman , Marek Jaromír
Published: July 2002

New binuclear complexes of the type [(Ni(aep)2)2ox](ClO4)2 (1) (aep = 2-(2-aminoethyl)pyridine, H2ox = oxalic acid), [(Ni(ept)H2O)2ox](NO3)2 (2), (ept = N-(2-aminoethyl)-1,3-diaminopropane), [(Cu(aep)H2O)2ox](ClO4)2 (3), [(Cu(ept))2ox](NO3)2·H2O (4) and [(Zn(L))2ox](ClO4)2·nH2O (L = ept, n = 0 (5); L = N,N'-bis(3-aminopropyl)-1,2-diaminoethane (3,2,3-tet), n = 4 (6)) have been prepared and studied by IR and UV-VIS spectroscopies. Spectroscopic data are consistent with oxalate-bridged structures between six-coordinate (N4O2 or N3O3) Ni(II) (compounds 1 and 2), (N2O3 or N3O2) Cu(II) (compounds 3 and 4) or (N3O2 or N4O2) Zn(II) (compounds 5 and 6). The crystal structure of [(Cu(aep)H2O)2ox](ClO4)2 (3) has been determined by single-crystal X-ray analysis. The copper atom is coordinated by two oxygen atoms of the oxalato ligand, two nitrogen atoms belonging to aep and one oxygen atom of water in a square-pyramidal arrangement. The intermetallic distance of Cu(1)-Cu(1a) is 5.204(2) Å. The temperature dependence of magnetic susceptibilities (94-298 K) was measured for 1 and 3. Magnetochemical measurements show that metal ions in these compounds are antiferromagnetically coupled, J = -17 and -160 cm-1 (H = -2JS1S2) for 1 and 3, respectively.
To the Mechanism of 2-Nitroanisole Carcinogenicity: in vitro Metabolism of 2-Nitroanisole Mediated by Peroxidasesand Xanthine Oxidase
Authors: Stiborová Marie , Schmeiser Heinz H. , Frei Eva
Published: July 2002

The in vitro enzymatic metabolism of carcinogenic 2-nitroanisole was investigated using peroxidases (horseradish peroxidase and prostaglandin H synthase) and xanthine oxidase catalyzing oxidative and reductive reactions, respectively. The oxidation of 2-nitroanisole catalyzed by horseradish peroxidase exhibits the Michaelis-Menten kinetics. The Michaelis constant (Km) and the maximal velocity (Vmax) values for this substrate were determined at pH 5.0, 7.0, 7.6 and 8.0. At optimal pH (7.6), the Km and Vmax values are 0.219 μmol/l and 34.45 pmol/min per nmol peroxidase, respectively. The oxidation of 2-nitroanisole is inhibited by radical trapping agents (NADH, ascorbate, glutathione and nitrosobenzene). This indicates that the peroxidase-mediated oxidation of 2-nitroanisole proceeds via a radical mechanism. Active oxygen species are formed during the horseradish peroxidase-catalyzed reactions in the presence of NADH, hydrogen peroxide and 2-nitroanisole. 2-Nitroanisole is also oxidized by mammalian prostaglandin H synthase. Using the nuclease P1-enhanced variation of the 32P-postlabelling assay, the formation of DNA adducts was detected in DNA treated with 2-nitroanisole and xanthine oxidase. No DNA binding was detected after oxidation of 2-nitroanisole with horseradish peroxidase and prostaglandin H synthase. The results presented (the formation of DNA adducts after 2-nitroanisole activation by xanthine oxidase and that of radicals and/or superoxide radicals during the reactions with peroxidases) strongly suggest the participation of 2-nitroanisole both in the initiation and in the promotion phases of carcinogenesis.
The Retro-Michael Reaction of 1,5-Dicarbonyl Compounds: Scope and Limitation
Authors: Wang Jian-Xin , Li Tong-Shuang
Published: July 2002

Under catalysis of NaOH or KOH adsorbed on glass wool and by using steam distillation, (20R,S)-4,4,5,14-tetramethyl-18,19-dinor-13,17-seco-5β,8α,9β,10α,14β-cholestane-13,17-dione (1) and 3,14-dioxo-14,15-seco-5α-cholestan-15-al (4) gave good yield (>59%) of the corresponding tricyclic compounds (8a, 8b and 10a) via a retro-Michael reaction at 250 °C. While 5-oxo-4-nor-3,5-secocholestan-3-oic acid (6) and ethyl 5-oxo-4-nor-3,5-secocholestan-3-oate (7) afforded low yield (<15%) of the retro-Michael cleavage products (12a, 12b) at the same conditions. Thus, the retro-Michael reaction worked well for 1,5-diketones and 1,5-keto aldehydes but gave poor yield for 1,5-keto esters and 1,5-keto acids.
Perfluoroalkylation of 6-Iodopurines by Trimethyl(perfluoroalkyl)silanes. Synthesis of 6-(Perfluoroalkyl)purine Bases, Nucleosides and Acyclic Nucleotide Analogues
Authors: Hocek Michal , Holý Antonín
Published: July 2002

A CuI/KF mediated perfluoroalkylation reaction of various 9-substituted 6-iodopurines 1 with trimethyl(trifluoromethyl)silane or heptafluoropropyl(trimethyl)silane was used for the synthesis of the corresponding 6-(trifluoromethyl)- and 6-(heptafluoropropyl)purine derivatives (purine bases, nucleosides and acyclic nucleotide analogues) in moderate to good yields.
Synthesis and Crystal Structures of Dimethylsilylene-Bridged (Amidocyclopentadienyl)dichlorotitanium(IV) Complexes with Various Substituents on the Cyclopentadienyl Ligand
Authors: Zemánek Jaroslav , Štěpnička Petr , Fejfarová Karla , Gyepes Róbert , Císařová Ivana , Horáček Michal , Kubišta Jiří , Varga Vojtech , Mach Karel
Published: July 2002

(Amidocyclopentadienyl)dichlorotitanium(IV) complexes of the general formula [TiCl2{η5:η1(N)-C5(1-SiMe2Nt-Bu-2,3,4-Me3-5-R)}], where R = H (6b), Ph (6c), 4-fluorophenyl (6d) and 1-methylallyl (6e) were synthesized and characterized by spectral methods. Solid-state structure of [TiCl2{η5:η1(N)-C5Me4(SiMe2Nt-Bu)}] (6a) and 6d determined by single-crystal X-ray diffraction showed that variation of the ring substituent R has only a negligible effect on the molecular structure of the complexes. The NMR spectra indicate that motion of the bulky substituent R in compounds 6c, 6d and 6e is hindered below ca 50 °C.
Linear Chaining of Etienic Acid Derivatives with the Amide Bond. Synthesis of Oligomeric Steroids
Authors: Černý Ivan , Buděšínský Miloš , Pouzar Vladimír , Drašar Pavel
Published: July 2002

Synthesis of linear molecules containing two to four steroid units connected with the amide bonds was developed. As a repeating unit, 3β-hydroxyandrost-5-ene-17β-carboxylic acid (etienic acid) was used. An active ester of this acid with N-hydroxysuccinimide and its 3-azido analogue were prepared and methods for the preparation of higher oligomers were studied.
Transient forces generated by projectiles on variable quality mouthguards monitored by instrumented impact testing
Authors: Warnet L , Greasley A
Published: July 2002

Objectives—(a) To determine the force-time trace that occurs when a spring mounted simulated upper jaw is impacted; (b) to examine if mouthguards of variable quality have significant influence on such force-time traces; (c) to attempt to relate physical events to the profile of the force-time traces recorded.

Methods—A simulated jaw, consisting of ceramic teeth inserted into a hard rubber arch reinforced with a composite jawbone, was fitted with various mouthguards as part of a previous round robin study. A clinical assessment distinguished good, bad, and poor mouthguards, and these were each fitted to the jaw, which was then submitted to instrumental impact tests under conditions expected to produce tooth fractures. The force-time trace was recorded for such impact events.

Results—The spring mounting method caused two distinct peaks in the force-time trace. The initial one was related to inertia effects and showed an increase in magnitude with impactor velocity as expected. The second peak showed features that were related to the differences in the mouthguards selected.

Conclusions—The use of a force washer within a conical ended impactor enabled force-time traces to be recorded during the impact of a spring mounted simulated jaw fitted with mouthguards of variable quality. The spring mounting system causes an initial inertial peak followed by a second peak once the spring mount has fully compressed. Good fitting guards, which keep most teeth intact, result in high stiffness targets that in turn generate high reaction forces in the impactor. If the spring mounting is omitted, the two peaks are combined to give even higher reaction forces. The force-time trace offers some potential for assessing both overall mouthguard performance and individual events during the impact sequence. Mouthguards with good retention to the jaw remained attached during the impact event and helped to preserve the structural integrity of the target. This in turn developed high forces in the second part of the force-time trace. Guards that detached during impact and allowed tooth fractures showed lower forces in the second part of the test. The force profile measured offered some quantitative support to, and agreement with, the observed clinical quality of the mouthguards.
Computerised cognitive assessment of concussed Australian Rules footballers
Authors: Makdissi M , Collie A , Maruff P , Darby D G , Bush A , McCrory P , Bennell K
Published: July 2002

Background—“Paper and pencil” neuropsychological tests play an important role in the management of sports related concussions. They provide objective information on the athlete's cognitive function and thus facilitate decisions on safe return to sport. It has been proposed that computerised cognitive tests have many advantages over such conventional tests, but their role in this domain is yet to be established.

Objectives—To measure cognitive impairment after concussion in a case series of concussed Australian Rules footballers, using both computerised and paper and pencil neuropsychological tests. To investigate the role of computerised cognitive tests in the assessment and follow up of sports related concussions.

Methods—Baseline measures on the Digit Symbol Substitution Test (DSST), Trail Making Test-Part B (TMT), and a simple reaction time (SRT) test from a computerised cognitive test battery (CogState) were obtained in 240 players. Tests were repeated in players who had sustained a concussive injury. A group of non-injured players were used as matched controls.

Results—Six concussions were observed over a period of nine weeks. At the follow up, DSST and TMT scores did not significantly differ from baseline scores in both control and concussed groups. However, analysis of the SRT data showed an increase in response variability and latency after concussion in the injured athletes. This was in contrast with a decrease in response variability and no change in latency on follow up of the control players (p<0.02).

Conclusion—Increased variability in response time may be an important cognitive deficit after concussion. This has implications for consistency of an athlete's performance after injury, as well as for tests used in clinical assessment and follow up of head injuries.
Effects of rapid weight loss on mood and performance among amateur boxers
Authors: Hall C J , Lane A M
Published: July 2002

Aims—To examine the effects of rapid weight loss on mood and performance among amateur boxers.

Methods—Participants were 16 experienced amateur boxers. In stage 1, structured interviews were used to assess the type of strategies that boxers used to reduce weight and the value of performing at their desired weight in terms of performance. In stage 2, boxers completed a 4 × 2 minute (1 minute recovery) circuit training session. Boxers completed the circuit training session on three different occasions with a week between each. The first test was used to familiarise the boxers with the circuit training task; the second and third tasks were at their training weight and championship weight, respectively. Participants were given one week to reduce their body weight to their championship weight using their preferred weight making strategies; boxers reduced their body weight by an average of 5.16% of body weight.

Results—Boxers typically lost weight by restricting fluid and food intake in the week leading to competition. Repeated measures multivariate analysis of variance results indicated that rapid weight loss among boxers was associated with poor performance, increased anger, fatigue, and tension, and reduced vigour.

Conclusions—Strategies used to make weight by boxers are associated with poor performance and a negative mood profile.
Validation of Ottawa ankle rules protocol in Greek athletes: study in the emergency departments of a district general hospital and a sports injuries clinic
Authors: Papacostas E , Malliaropoulos N , Papadopoulos A , Liouliakis C
Published: July 2002

Objective—To validate the Ottawa ankle rules protocol for predicting ankle and midfoot fractures in Greek athletes.

Method—A prospective survey in the emergency departments of a district general hospital and a sports injury clinic in Greece over nine months. A clinical evaluation was made of 122 patients with acute ankle and/or midfoot injury, and then radiographs were taken.

Results—Nine ankle and eight midfoot fractures were detected. The sensitivity of the Ottawa ankle rules protocol in predicting fractures in both the malleolar and midfoot zones was 100%. The negative predictive value for each of these areas was also 1.0. Specificity was estimated to be 0.3 for ankle fractures and 0.4 for midfoot fractures. Positive predictive values were 0.16 and 0.28 respectively. A possible reduction of up to 28.7% was found in the need for radiography.

Conclusions—Use of the Ottawa ankle rules protocol in evaluating injured Greek athletes resulted in 100% sensitivity when performed by orthopaedic residents or sports medicine doctors, and had the potential to reduce the use of radiography.
Exertion induced rhabdomyolysis of the long head of the triceps: Figure 1
Authors: Goubier J-N , Silbermann Hoffman O , Oberlin C
Published: July 2002

The case is reported of bilateral rhabdomyolysis of the long head of the triceps following intensive exercise in a 30 year old male weightlifter. The diagnosis was based on myalgias localised to one muscle and raised levels of muscle enzymes. Magnetic resonance imaging helped to locate the site and extent of muscular involvement. Treatment consisted of complete rest and adequate intravenous perfusion to allow clearance of the clinical and biological abnormalities and prevent renal involvement.
Soluble E-cadherin is a valid prognostic marker in gastric carcinoma
Authors: Chan A O O , Lam S K , Chu K M , Lam C M , Kwok E , Leung S Y , Yuen S T , Law S Y K , Hui W M , Lai K C , Wong C Y , Hu H C , Lai C L , Wong J
Published: July 2002

BACKGROUND

Gastric cancer remains a major cause of cancer mortality globally but no good prognostic tumour marker is available. Soluble fragment of E-cadherin protein has been reported to increase in the sera of patients with cancer and recently was found to be elevated in 67% of patients with gastric cancer.

AIMS

To investigate if serum soluble E-cadherin is a valid prognostic marker in gastric cancer.

METHODS

Concentrations of soluble E-cadherin from 116 patients with histologically confirmed gastric adenocarinoma and 40 healthy subjects were measured using an immunoenzymometric method with a commercially available sandwich ELISA kit based on monoclonal antibodies.

RESULTS

The logarithm of the means of soluble E-cadherin concentration was significantly higher in patients with gastric cancers (mean 3.85 (SD 0.28)) than in healthy subjects (3.71 (0.18)) (p=0.001), and in palliative/conservatively treated cancers (3.91 (0.35)) than in operable cancers (3.78 (0.19)) (p=0.015). The logarithm of the concentrations correlated with tumour size (p=0.032) and carcinoembryonic antigen concentrations (p=0.001). The cut off value calculated from discriminant analysis on operability and inoperability/palliative treatment was 7025 ng/ml. Soluble E-cadherin concentrations higher than this cut off value predicted tumour (T4) depth invasion (p=0.020, confidence interval (CI) 1.008–1.668) and palliative/conservative treatment (p=0.023, CI 1.038–2.514). In contrast, the relative risks for lymph node (N2) metastasis, distant metastasis, and stage III/IV disease were 1.41, 1.33, and 1.55 respectively, despite not reaching statistical significance.

CONCLUSION

Serum soluble E-cadherin is a potential valid prognostic marker for gastric cancer. A high concentration predicts palliative/conservative treatment and T4 invasion.
‘End-of-life’ decision making within intensive care - objective, consistent, defensible?
Authors: Ravenscroft Andrew J , Bell M D Dominic
Published: July 2002

Objective—To determine the objectivity, consistency and professional unanimity in the initiation, continuation and withdrawal of life-prolonging procedures in intensive care–to determine methods, time-scale for withdrawal and communication with both staff and relatives–to explore any professional unease about legality, morality or professional defensibility.

Design—A structured questionnaire directed at clinical nurse managers for intensive care.

Setting—All intensive care units in the Yorkshire region.

Results—The survey reported a lack of consistency and objectivity in decision making in this area, with accompanying unease amongst staff.

Conclusions—There is a need to work towards more consistent care, both before and during admission, for the protection of the individual patient and to allow rational assessment of intensive care need. Comprehensive audit should lead to objective defensible decisions and facilitate informed choice. More open debate and better communication should minimise this issue as a source of stress amongst staff in intensive care.
One principle and a fourth fallacy of disability studies
Authors: Harris John
Published: July 2002

This brief paper shows that the idea of benefits to the subject compensating for the harms of disability is at best self defeating and at worst sinister. Equally benefits to third parties while real are dubious as compensating factors. This shows that disabilities are just that, a net loss and not a net gain.
Don't cry for us Argentinians: two decades of teaching medical humanities
Authors: Acuña Leopoldo E
Published: July 2002

Medical humanities—history, literature, anthropology, ethics and fine arts applied to medicine—play an important role in medical education. For more than 20 years an effort has been made to obtain an academic identity for such a multidisciplinary approach. A distinction between humanitarianism and humanism is attempted here, the former being associated with medical care and the latter with medical education. In order more precisely to define the relationship between the arts and medicine, an alternative term “medical kalology”, as-yet-unsanctioned, coined after the rules of medical terminology, is proposed.

The Department of Medical Humanities in the School of Medicine, National University of La Plata, submits the following apologia: Don't cry for us Argentinians, since the teaching of medical humanities has helped our doctors to function more truly humanistically during the past two decades, and we intend to continue with this calling in the future.
Workplace exposures and oesophageal cancer
Authors: Parent Marie-Élise , Siemiatycki Jack , Fritschi Lin
Published: July 2002

OBJECTIVES

To describe the relation between oesophageal cancer and many occupational circumstances with data from a population based case-control study.

METHODS

Cases were 99 histologically confirmed incident cases of cancer of the oesophagus, 63 of which were squamous cell carcinomas. Various control groups were available; for the present analysis a group was used that comprised 533 population controls and 533 patients with other types of cancer. Detailed job histories were elicited from all subjects and were translated by a team of chemists and hygienists for evidence of exposure to 294 occupational agents. Based on preliminary results and a review of literature, a set of 35 occupational agents and 19 occupations and industry titles were selected for this analysis. Logistic regression analyses were adjusted for age, birthplace, education, respondent (self or proxy), smoking, alcohol, and β-carotene intake.

RESULTS

Sulphuric acid and carbon black showed the strongest evidence of an association with oesophageal cancer, particularly squamous cell carcinoma. Other substances showed excess risks, but the evidence was more equivocal—namely chrysotile asbestos, alumina, mineral spirits, toluene, synthetic adhesives, other paints and varnishes, iron compounds, and mild steel dust. There was considerable overlap in occupational exposure patterns and results for some of these substances may be mutually confounded. None of the occupations or industry titles showed a clear excess risk; the strongest hints were for warehouse workers, food services workers, and workers from the miscellaneous food industry.

CONCLUSIONS

The data provide some support for an association between oesophageal cancer and a handful of occupational exposures, particularly sulphuric acid and carbon black. Many of the associations found have never been examined before and warrant further investigation.
Mental health insurance claims among spouses of frequent business travellers
Authors: Dimberg L A , Striker J , Nordanlycke-Yoo C , Nagy L , Mundt K A , Sulsky S I
Published: July 2002

Objectives: Following up on two earlier publications showing increased psychological stress and psychosocial effects of travel on the business travellers this study investigated the health of spouses of business travellers.

Methods: Medical claims of spouses of Washington DC World Bank staff participating in the medical insurance programme in 1997–8 were reviewed. Only the first of each diagnosis with the ninth revision of the international classification of diseases (ICD-9) recorded for each person was included in this analysis. The claims were grouped into 28 diagnostic categories and subcategories.

Results: There were almost twice as many women as men among the 4630 identified spouses. Overall, male and female spouses of travellers filed claims for medical treatment at about a 16% higher rate than spouses of non-travellers. As hypothesised, a higher rate for psychological treatment was found in the spouses of international business travellers compared with non-travellers (men standardised rate ratios (RR)=1.55; women RR=1.37). For stress related psychological disorders the rates tripled for both female and male spouses of frequent travellers (≥ four missions/year) compared with those of non-travelling employees. An increased rate of claims among spouses of travellers versus non-travellers was also found for treatment for certain other diagnostic groups. Of these, diseases of the skin (men RR=2.93; women RR=1.41) and intestinal diseases (men RR=1.31; women RR=1.47) may have some association with the spouses' travel, whereas others, such as malignant neoplasms (men RR=1.97; women RR=0.79) are less likely to have such a relation.

Conclusion: The previously identified pattern of increased psychological disorders among business travellers is mirrored among their spouses. This finding underscores the permeable boundary between family relations and working life which earlier studies suggested, and it emphasises the need for concern within institutions and strategies for prevention.
Reversible sensorineural hearing loss after non-otological surgery under general anaesthetic
Authors: Pau H , Selvadurai D , Murty G E
Published: July 2002

Acute sensorineural hearing loss can occur after both otolaryngological and non-otolaryngological procedures. The mechanism of such hearing loss remains unproved; but nitrous oxide has been implicated and where used, attendants should be aware of its potential damage to hearing. It is essential that patients with sudden hearing loss are identified as soon as possible as the recovery rate had been shown to be higher in those who presented early; and as our case demonstrates, complete recovery is possible. Anaesthetists, non-otolaryngological surgeons, and ward nurses must be aware of this early postoperative complication if appropriate treatment is to be instituted.
Teaching medical undergraduates basic clinical skills in hospice—is it practical?
Authors: Franks Alison L
Published: July 2002

Aim

Basic clinical skills teaching to medical undergraduates was a new departure for the hospice stimulated by the changing philosophies and organisation of students' training. This study was undertaken to assess the practicalities of the venture.

Method

Questionnaires were designed for each of the three major groups of people involved, namely the students, the patients, and the hospice nurses. Involved patients completed theirs after teaching sessions, while the students and nurses were given two different questionnaires each, one at the start and another at the end of the academic year.

Results

All students completed both questionnaires. Overall they had acquired adequate skills to pass their end of year assessments and considered themselves more comfortable with difficult situations than may otherwise have been the case. The majority of patients had enjoyed the experience and found it personally educational and a change to hospice routines. The nurses' response rates were very poor, limiting any conclusions that could be drawn.

Conclusion

The venture was successful, stimulating, and practical for patients and students. Its impact on the nurses remains uncertain but, by their unusual lack of opinion expression, it can be inferred tentatively that this was minimal.
Management of the impalpable testis: a six year review together with a national experience
Authors: Williams E V , Appanna T , Foster M E
Published: July 2002

The management of undescended testes remains variable, and the use of laparoscopy for localisation is controversial. This study reviews the need for laparoscopy and also assesses the current practice among a cohort of surgeons.

A retrospective review of all patients undergoing orchidopexy was performed, together with a postal survey of all members of the Welsh Surgical Society.

Of the 139 orchidopexies performed, the testis was deemed impalpable in 39 (28%) cases. All patients were treated with groin exploration, and only in two (5%) patients was the testis not located. From the survey, replies were received from 90 (81%) surgeons, of whom 65 (72%) were still performing orchidopexy. Forty eight (74%) surgeons performed orchidopexy between the age of 2 and 3, and only 32 (36%) performed preoperative investigations. The follow up period was variable with the majority of patients seen at six weeks.

Laparoscopy for the impalpable testis is not initially warranted. An inguinal exploration is regarded as the definitive investigation. This has the advantage of providing the diagnosis and treatment in the majority of cases.
Management of neurogenic dysphagia
Authors: Bakheit A M O
Published: July 2002

Dysphagia is common in patients with neurological disorders. It may result from lesions in the central or peripheral nervous system as well as from diseases of muscle and disorders of the neuromuscular junction. Drugs that are commonly used in the management of neurological conditions may also precipitate or aggravate swallowing difficulties in some patients. Neurogenic dysphagia often results in serious complications, including pulmonary aspiration, dehydration, and malnutrition. These complications are usually preventable if the dysphagia is recognised early and managed appropriately.
Use of corporate sponsorship as a tobacco marketing tool: a review of tobacco industry sponsorship in the USA, 1995-99
Authors: Rosenberg N Jennifer , Siegel Michael
Published: July 2002

OBJECTIVE

To describe the nature and extent of tobacco company sponsorship in the USA during the period 1995-99 and analyse this sponsorship in a marketing context.

DESIGN

A cross-sectional study of tobacco company sponsorships identified through a customised research report from IEG Inc, and from internet web site searches.

METHODS

First, a customised report was received from IEG Inc, which identified sponsorship activities for Philip Morris, RJ Reynolds, Brown & Williamson, Lorillard, and US Tobacco for the years 1997 and 1998. Second, the internet was systematically searched for tobacco industry sponsorships during the period 1995-99 by the same parent companies and their respective brands.

RESULTS

During the period 1995-99, tobacco companies sponsored at least 2733 events, programmes, and organisations in the USA. Sponsorships involved all 50 states and the District of Columbia, and the minimum total funding amount of these sponsorships was $365.4 million. Tobacco corporate sponsorships involved numerous small, community based organisations, both through direct funding and through grants to larger umbrella organisations, and many of these organisations were part of the public health infrastructure.

CONCLUSIONS

Tobacco corporate sponsorship serves as an important marketing tool for tobacco companies, serving both a sales promotion and public relations function. Public health practitioners need to develop better surveillance systems for monitoring tobacco sponsorship, to seek out alternative funding sources for tobacco company sponsored events and organisations, and to consider promoting a ban on tobacco sponsorship, possibly linking such regulation to the creation of alternative funding sources.
Reflections on lichenology: achievements over the last 40 years and challenges for the future
Authors: Richardson D HS
Published: July 2002

In June 2000, at the joint meeting of the Canadian Botanical Association and the Canadian Society of Plant Physiologists, the author of this review was presented with the George Lawson Medal for lifelong contributions to botany and was invited to prepare a special contribution for the Canadian Journal of Botany. Subsequently, an invitation was received to give the Swinscow Lecture to the British Lichen Society and the Linnean Society in London. This commentary is a written version of that January 2001 lecture and presents a personalized view of developments in those areas of lichenology studied by the author during a career in Canada and other parts of the world. Aspects touched upon include lichen identification, spore dispersal, nutrient transfer between the symbionts, water relations, and lichen strategies in particular climatic regions. The value of lichens for monitoring pollutants is noted, and the developing problem of lichen conservation is discussed. Finally, a plea is made regarding the value of field teaching and field excursions with respect to recruiting the next generation of lichenologists.Key words: lichens, asci, carbohydrate transfer, ecophysiology, pollution, old-growth forests, lichen societies.
Ca2+binding to bovine lactoferrin enhances protein stability and influences the release of bacterial lipopolysaccharide
Authors: Rossi Paola , Giansanti Francesco , Boffi Alberto , Ajello Maria , Valenti Piera , Chiancone Emilia , Antonini Giovanni
Published: July 2002

Bovine lactoferrin (bLf) is known to damage the outer membrane of Gram-negative bacteria by binding to bacterial lipopolysaccharide (LPS). We report that LPS is released from bacterial outer membranes also when apo- or metal-saturated Lf is separated from bacterial cells by a dialysis membrane. This process occurs in phosphate-buffered saline with no added Ca2+and Mg2+and is hindered by addition of these cations. The effect of bLf is similar to that induced by EDTA and has been ascribed to chelation of Ca2+. In fact, it may be envisaged that Ca2+-binding sites on LPS have different affinities and that bLf can remove those ions that are more weakly bound. Ca2+binding does not alter Lf iron-binding properties significantly or its UV and CD spectral features but brings about changes in the FT-IR bands due to carboxylate residues. Ca2+binding is characterized by an apparent dissociation constant of 6 µM and a stoichiometry of 1.55 Ca2+per Lf molecule; it enhances bLf stability towards chemical and thermal denaturation. The increase in stability takes place in both the apo- and iron-saturated forms but not in the desialilated protein, indicating that the carboxylate groups of the sialic acid residues present on two of the glycan chains are involved in Ca2+binding.Key words: lactoferrin, calcium, antibacterial activity, lipopolysaccharides, protein stability, denaturation.
Liquefied strength ratio from liquefaction flow failure case histories
Authors: Olson Scott M , Stark Timothy D
Published: July 2002

The shear strength of liquefied soil, su(LIQ), mobilized during a liquefaction flow failure is normalized with respect to the vertical effective stress (σ 'vo) prior to failure to evaluate the liquefied strength ratio, su(LIQ)/σ 'vo. Liquefied strength ratios mobilized during 33 cases of liquefaction flow failure are estimated using a procedure developed to directly back-analyze the liquefied strength ratio. In ten cases, sufficient data regarding the flow slide are available to incorporate the kinetics, i.e., momentum, of failure in the back-analysis. Using liquefied strength ratios back-calculated from case histories, relationships between liquefied strength ratio and normalized standard penetration test blowcount and cone penetration test tip resistance are proposed. These relationships indicate approximately linear correlations between liquefied strength ratio and penetration resistance up to values of qc1and (N1)60of 6.5 MPa and 12 blows/ft (i.e., blows/0.3 m), respectively.Key words: liquefaction, flow failure, liquefied shear strength, stability analysis, kinetics, penetration resistance.