bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple eIF4GI-Specific Protease Activities Present in Uninfected and Poliovirus-Infected Cells
Authors: Zamora Miguel , Marissen Wilfred E. , Lloyd Richard E.
Published: July 2002

Cleavage of eukaryotic translation initiation factor 4GI (eIF4GI) is required for shutoff of host cell translation during poliovirus (PV) infection of HeLa cells. Reports published by several groups have led to confusion whether this cleavage is mediated by viral 2A protease (2A
pro
) or a putative cellular enzyme (termed eIF4Gase) which is activated by 2A
pro
or other aspects of viral infection. Here we have further investigated eIF4Gase activities in PV-infected cells. Column purification of eIF4GI cleavage activity separated two activities which generated N-terminal cleavage products of different lengths. Both activities were detected using either native eIF4G or radiolabeled recombinant eIF4G as the substrate. Analysis of cleavage products formed by each activity on native and mutant substrates suggests that one activity cleaves eIF4G1 at or very near the 2A
pro
cleavage site and the other activity cleaves approximately 40 residues upstream of the 2A
pro
cleavage site. When PV infections in HeLa cells were supplemented with 2 mM guanidine, which indirectly limits expression of 2A
pro
, two distinct C-terminal cleavage fragments of eIF4GI were detected. These C-terminal cleavage fragments of eIF4GI were purified from infected cells, and a new eIF4GI cleavage site was mapped to a unique site 43 amino acids upstream of the known 2A
pro
cleavage site. Further, eIF4GI cleavage in vivo could be blocked by addition of zVAD to PV-guanidine infections. zVAD is a broad-spectrum caspase inhibitor which had no effect on 2A
pro
cleavage activity or PV polyprotein processing. Lastly, similar types of eIF4Gase cleavage activities were also detected in uninfected cells under various conditions, including early apoptosis or during cell cycle transit. The data suggest that the same types of eIF4GI cleavage activities which are generated in PV-infected cells can also be generated in the absence of virus. Taken together, the data support a model in which multiple cellular activities process eIF4GI in PV-infected cells, in addition to 2A
pro
.
Vaccine-Induced Immune Responses in Rodents and Nonhuman Primates by Use of a Humanized Human Immunodeficiency Virus Type 1
pol
Gene
Authors: Casimiro Danilo R. , Tang Aimin , Perry Helen C. , Long Romnie S. , Chen Minchun , Heidecker Gwendolyn J. , Davies Mary-Ellen , Freed Daniel C. , Persaud Natasha V. , Dubey Sheri , Smith Jeffrey G. , Havlir Diane , Richman Douglas , Chastain Michael A. , Simon Adam J. , Fu Tong-Ming , Emini Emilio A. , Shiver John W.
Published: July 2002

A synthetic gene consisting of the reverse transcriptase (RT) and integrase (IN) domains of human immunodeficiency virus type 1 (HIV-1)
pol
was constructed using codons most frequently used in humans. The humanized
pol
gave dramatically improved levels of Rev-independent, in vitro protein production in mammalian cells and elicited much stronger cellular immunity in rodents than did virus-derived gene. Specifically, BALB/c mice were immunized with plasmids and/or recombinant vaccinia virus constructs expressing the synthetic gene. High frequencies of Pol-specific T lymphocytes were detected in these animals by the gamma interferon enzyme-linked immunospot assay against pools of short overlapping peptides. Characterization of the stimulatory peptides from these pools indicates that the optimized gene constructs are able to effectively activate both CD4
+
and CD8
+
T cells. Immunization of rhesus macaques with DNA vaccines expressing the humanized
pol
coupled to a human tissue plasminogen activator leader sequence led to pronounced in vitro cytotoxic T-lymphocyte killing activities and enhanced levels of circulating Pol-specific T cells, comparable to those observed in HIV-1-infected human subjects. Thus, optimizing the immunogenic properties of HIV-1 Pol at the level of the gene sequence validates it as an antigen and provides an important step toward the construction of a potent
pol
-based HIV-1 vaccine component.
DNA Cleavage and Packaging Proteins Encoded by Genes U
L
28, U
L
15, and U
L
33 of Herpes Simplex Virus Type 1 Form a Complex in Infected Cells
Authors: Beard Philippa M. , Taus Naomi S. , Baines Joel D.
Published: July 2002

Previous studies have indicated that the U
L
6, U
L
15, U
L
17, U
L
28, U
L
32, and U
L
33 genes are required for the cleavage and packaging of herpes simplex viral DNA. To identify proteins that interact with the U
L
28-encoded DNA binding protein of herpes simplex virus type 1 (HSV-1), a previously undescribed rabbit polyclonal antibody directed against the U
L
28 protein fused to glutathione
S
-transferase was used to immunopurify U
L
28 and the proteins with which it associated. It was found that the antibody specifically coimmunoprecipitated proteins encoded by the genes U
L
28, U
L
15, and U
L
33 from lysates of both HEp-2 cells infected with HSV-1(F) and insect cells infected with recombinant baculoviruses expressing these three proteins. In reciprocal reactions, antibodies directed against the U
L
15- or U
L
33-encoded proteins also coimmunoprecipitated the U
L
28 protein. The coimmunoprecipitation of the three proteins from HSV-infected cells confirms earlier reports of an association between the U
L
28 and U
L
15 proteins and represents the first evidence of the involvement of the U
L
33 protein in this complex.
HLA-Cw*04
and Hepatitis C Virus Persistence
Authors: Thio Chloe L. , Gao Xiaojiang , Goedert James J. , Vlahov David , Nelson Kenrad E. , Hilgartner Margaret W. , O'Brien Stephen J. , Karacki Peter , Astemborski Jacquie , Carrington Mary , Thomas David L.
Published: July 2002

In studies of acute hepatitis C virus (HCV) infection, the early host immune response is one of the determinants of viral persistence. The class I human leukocyte antigens (HLA), which present foreign antigen to cytolytic T cells, are integral components of this response. We hypothesized that the highly polymorphic
HLA
genes affect the outcome of an HCV infection. To test this hypothesis, we molecularly typed 231 persons with well-documented clearance of an HCV infection and 444 matched persistently infected persons.
HLA-A*1101
(odds ratio [OR], 0.49; 95% confidence interval [95% CI], 0.27 to 0.89),
HLA-B*57
(OR, 0.62; 95% CI, 0.39 to 1.00), and
HLA-Cw*0102
(OR, 0.43; 95% CI, 0.21 to 0.89) were associated with viral clearance, whereas
HLA-A*2301
(OR, 1.78; 95% CI, 1.01 to 3.11) and
HLA-Cw*04
(OR, 1.78; 95% CI, 1.21 to 2.59) were associated with viral persistence.
HLA-Cw*04
is in strong linkage disequilibrium with
HLA-B*53
and
HLA-B*35
, but only
HLA-B*53
(OR, 1.70; 95% CI, 0.95 to 3.06) and the
Cw*04-B*53
haplotype (OR, 1.76; 95% CI, 0.94 to 3.26) were weakly associated with viral persistence.
HLA-B*53
has similar, but not necessarily identical, binding specificity to some
HLA-B*35
subtypes (
B*35-Px
group). The association with the
B*35-Px
group was less strong than with
HLA-B*53
alone. The association of
HLA-Cw*04
with HCV persistence was codominant (two copies of the gene were more strongly associated with persistence than one copy). However,
HLA-Cw*04
was not associated with HCV RNA levels among the persistently infected individuals. Since Cw*04 is a ligand for the killer immunoglobulin-like receptors on natural killer cells, these cells may be involved in recovery from HCV infection. Further investigation is needed to understand the relationship between class I alleles and HCV clearance.
Human Immunodeficiency Virus Type 1 Neutralization Measured by Flow Cytometric Quantitation of Single-Round Infection of Primary Human T Cells
Authors: Mascola John R. , Louder Mark K. , Winter Christine , Prabhakara Ranjani , De Rosa Stephen C. , Douek Daniel C. , Hill Brenna J. , Gabuzda Dana , Roederer Mario
Published: July 2002

There is currently intensive research on the design of novel human immunodeficiency virus type 1 (HIV-1) vaccine immunogens that can elicit potent neutralizing antibodies. A prerequisite for comparing and optimizing these strategies is the ability to precisely measure neutralizing antibody responses. To this end, we sought to develop an assay that directly quantifies single-round HIV-1 infection of peripheral blood mononuclear cells (PBMC). Initial experiments demonstrated that essentially all productively infected PBMC could be identified by flow cytometric detection of intracellular p24 antigen (p24-Ag). After infection of PBMC with HIV-1, p24
+
lymphocytes could be distinguished beginning 1 day postinfection, and the majority of CD8
−
T cells were p24-Ag positive by 3 to 4 days postinfection. To directly quantify first-round infection, we included a protease inhibitor in PBMC cultures. The resulting 2-day assay was highly sensitive and specific for the detection of HIV-1-infected PBMC. Serial dilutions of virus stocks demonstrated that the number of target cells infected was directly related to the amount of infectious virus input into the assay. In neutralization assays, the flow cytometric enumeration of first-round infection of PBMC provided quantitative data on the number of target cells infected and on the inactivation of infectious virus due to reaction with antibody. We also used this single-round assay to compare the percentage of cells expressing p24-Ag to the number of copies of HIV-1
gag
per 100 PBMC. The precision and reproducibility of this assay will facilitate the measurement of HIV-1 neutralization, particularly incrementally improved neutralizing antibody responses generated by new candidate vaccines.
Measles Virus Preferentially Transduces the Basolateral Surface of Well-Differentiated Human Airway Epithelia
Authors: Sinn Patrick L. , Williams Greg , Vongpunsawad Sompong , Cattaneo Roberto , McCray Paul B.
Published: July 2002

Measles virus (MV) is typically spread by aerosol droplets and enters via the respiratory tract. The progression of MV infection has been widely studied; yet, the pathway for virus entry in polarized human airway epithelia has not been investigated. Herein we report the use of a replication-competent Edmonston vaccine strain of MV expressing enhanced green fluorescent protein (MV-eGFP) to infect primary cultures of well-differentiated human airway epithelia. Previous studies with polarized Caco-2 cells (intestine-derived human epithelia) and MDCK cells (kidney-derived canine epithelia) demonstrated that MV primarily infected and exited the apical surface. In striking contrast, our results indicate that MV preferentially transduces human airway cells from the basolateral surface; however, virus release remains in an apical direction. When MV-eGFP was applied apically or basolaterally to primary cultures of airway epithelia, discrete foci of eGFP expression appeared and grew; however, the cell layer integrity was maintained for the duration of the study (7 days). Interestingly, utilizing immunohistochemistry and confocal microscopy, we observed widespread expression of the receptor for the vaccine strain of MV (CD46) at greatest abundance on the apical surface of the differentiated human airway epithelia as well as in human tracheal tissue sections. These data suggest that the progression of MV infection through the respiratory epithelium may involve pathways other than direct binding and entry through the apical surface of airway epithelia.
NK T Cells Contribute to Expansion of CD8+T Cells and Amplification of Antiviral Immune Responses to Respiratory Syncytial Virus
Authors: Johnson Teresa R. , Hong Seokmann , Van Kaer Luc , Koezuka Yasuhiko , Graham Barney S.
Published: July 2002

CD1d-deficient mice have normal numbers of T lymphocytes and natural killer cells but lack Vα14+natural killer T cells. Respiratory syncytial virus (RSV) immunopathogenesis was evaluated in 129×C57BL/6, C57BL/6, and BALB/c CD1d−/−mice. CD8+T lymphocytes were reduced in CD1d−/−mice of all strains, as shown by cell surface staining and major histocompatibility complex class I tetramer analysis, and resulted in strain-specific alterations in illness, viral clearance, and gamma interferon (IFN-γ) production. Transient activation of NK T cells in CD1d+/+mice by α-GalCer resulted in reduced illness and delayed viral clearance. These data suggest that early IFN-γ production and efficient induction of CD8+-T-cell responses during primary RSV infection require CD1d-dependent events. We also tested the ability of α-GalCer as an adjuvant to modulate the type 2 immune responses induced by RSV glycoprotein G or formalin-inactivated RSV immunization. However, immunized CD1-deficient or α-GalCer-treated wild-type mice did not exhibit diminished disease following RSV challenge. Rather, some disease parameters, including cytokine production, eosinophilia, and viral clearance, were increased. These findings indicate that CD1d-dependent NK T cells play a role in expansion of CD8+T cells and amplification of antiviral responses to RSV.
Absolute Crystal Structure Determination of Ergot Alkaloid - Dihydroergocristine Methanesulfonate Monohydrate
Authors: Čejka Jan , Ondráček Jan , Hušák Michal , Kratochvíl Bohumil , Jegorov Alexandr , Stuchlík Josef
Published: July 2002

Dihydroergocristine methanesulfonate monohydrate crystallizes in orthorhorhombic space group P21212 (No. 18) with Z = 4, a = 12.736(2) Å, b = 39.089(5) Å, c = 7.130(1) Å, V = 3549.6(9) Å3. The indole moiety is nearly planar, both the ergoline ring C and the tripeptide ring F addopt an envelope E6 conformation. The ergoline ring D and the tripeptide ring E have a chair 1C4 conformation. The conformation of the ring G is between E1 and 5T1. The benzene ring H is planar. The structure was solved by direct methods and refined anisotropically to the final R value of 0.078 for 4219 statistically significant observed reflections [I o 1.96s(I)]. The absolute chirality was determined based on anomalous dispersion as: C4 (R), C8 (R), C6 (R), C17 (R), C25 (S), C24 (S), C19 (S).
Effect of Concentrated Uni-Univalent Electrolytes on Oxidation Kinetics of Sulfur of Chelate Ligands in Co(III) Complexes with H2O2, IO4- and S2O82-
Authors: Vollárová Oľga , Benko Ján
Published: July 2002

The effect of concentrated uni-univalent electrolytes on the oxidation kinetics of sulfur in the chelate ligands (-SCH2CH2NH2-)-, (-SOCH2CH2NH2-)-, (-SCH2COO-)2-, and (-SOCH2COO-)2- bound in Co(III) complexes with various oxidants (H2O2, IO4-, S2O82- has been studied at 298.2 K. The results show that the changes observed in the rate constants are due to interactions between the supporting electrolyte and solvent.
Competitive Hydrogenation of Unsaturated Hydrocarbons by Hydrogen Transfer from Ammonium Formateon a Palladium Catalyst
Authors: Dobrovolná Zuzana , Červený Libor
Published: July 2002

Competitive hydrogenation of alkenes (cyclohexene, hex-1-ene, hept-1-ene, oct-1-ene) and dienes (octa-1,7-diene, cyclohexa-1,3-diene) was carried out by catalytic hydrogen transfer from ammonium formate on palladium in methanol. The adsorptivity and reactivity of the hydrocarbons decreased in the series: cyclic diene > linear diene > linear 1-alkene > cyclic alkene.
Characterization of Glycoprotein Fraction from Carp Pituitaries Isolated Using Concanavalin A as the Affinity Ligand
Authors: Hulová Irena , Barthová Jana , Ryšlavá Helena , Kašička Václav
Published: July 2002

Glycoproteins that have affinity to Concanavalin A were isolated from the acetone-dried pituitaries of common carp (Cyprinus carpio L.). Two fractions of glycoproteins were separated using gel chromatography on Superdex 75HR. The fraction with lower molecular weight (30 000) corresponding to the carp gonadotropin cGtH II was composed of two subunits as determined using SDS-PAGE. This protein fraction was further divided into four components using reversed-phase HPLC. Two fractions were pure α and β subunits of cGtH II as follows from immunodetection and from determination of N-terminal amino acid sequences. The other two were a mixture of α and β subunits as was also revealed by N-terminal analysis. Capillary electrophoresis was also used for characterization of isolated glycoproteins.
The Effect of Electrostatic Properties and Abibility to Form Hydrogen-Bonds on the Activity of Brassinosteroid Side-Chain Analogs
Authors: Brosa Carme , Zamora Ismael , Terricabras Emma , Kohout Ladislav
Published: July 2002

Molecular modeling studies on three brassinosteroids analogs having ester and amide function in the side chain have been performed. The activity of such compounds from the structural point of view is discussed in terms of electrostatic potential and ability to form hydrogen bonds.
Cycloaddition Reactions of Furo[2,3-b]pyrroles
Authors: Sleziak Róbert , Krutošíková Alžbeta
Published: July 2002

Reactions of furo[2,3-b]pyrroles with dimethyl butynedioate and ethyl propynoate were investigated. The reaction course is influenced by the substituents on the fused system. Products of [4+2]cycloaddition to the furan ring leading to indole derivatives have been observed. In the case of the reaction of methyl 6H-furo[2,3-b]pyrrole-5-carboxylate (1a) with dimethyl butynedioate, products of [4+2]cycloaddition to the furan ring as well as of Michael addition to the pyrrole ring leading to N-substituted indole derivative 3 have been observed.
Platinum(II) Complexes of Pyridines. A Review
Authors: Śliwa Wanda , Deska Małgorzata
Published: July 2002

The chemistry of platinum(II) complexes of pyridine and related compounds is reviewed. Also the oxidative addition reaction to platinum(II) complexes of pyridines, as a method of conversion of Pt(II) into Pt(IV) species is described. A review with 90 references.
Sterically Crowded Heterocycles. X. A New Mechanistic Approach to the Ferricyanide Oxidation of 4,6'-Disubstituted 1-(Pyridin-2'-yl)-2,6-diphenylpyridinium Salts
Authors: Pohl Radek , Böhm Stanislav , Kuthan Josef
Published: July 2002

The oxidations of the title perchlorates, bearing the sterically diverse 6'-substituents (H, Me, Et, i-Pr, n-Bu, t-Bu and Ph) in two series with the same 4-substituents (Ph and t-Bu) lead to pairs of isomeric 3',5-disubstituted (Z)-1'-phenyl-3'-(2-phenylimidazo[1,2-a]pyridin-3-yl)prop-2'- en-1'-ones and 3,6'-disubstituted [5-phenyl-1-(6'-pyridin-2'-yl)-1H-pyrrol-2-yl](phenyl)methanones except where the both variable substituents are t-Bu and then only pyrrolic product is formed. Considering steric interactions of the substituents in some intermediate and/or transition states a multistep mechanism for the oxidative transformation is proposed and supported by model PM3-PECI calculations of some radical intermediates.
Regioselective Double Cyclisation of 1,2,4,5-Tetrakis(bromomethyl)benzene with Tosylated Diethylenetriamine. Towards Conformationally Biased Bis(perazacrown) Receptors
Authors: Hodačová Jana , Závada Jiří , Junk Peter C.
Published: July 2002

Of three possible tricyclic regioisomers, the reaction of 1,2,4,5-tetrakis(bromomethyl)benzene with tosylated diethylenetriamine affords selectively a single product which has been assigned structure 4,7,10,15,18,21-hexakis(4-methylbenzenesulfonyl)-4,7,10,15,18,21-hexa- azatricyclo[11.9.1.12,12]tetracosa-1(23),2(24),12-triene with the aid of X-ray crystal analysis.
Synthesis of 21-Hydroxy-6β,19-epoxypregn-4-ene-3,20-dione
Authors: Hniličková Jaroslava , Kohout Ladislav
Published: July 2002

21-Hydroxy-6β,19-epoxypregn-4-ene-3,20-dione was prepared from 20-oxopregn-5-en-3β-yl acetate in seven steps.
1-Deamino-1(15)-carba and -Dicarba Analogues of Endothelin-1
Authors: Hlaváček Jan , Marcová Renáta , Buděšínský Miloš , Slaninová Jiřina
Published: July 2002

Sulfanyl-methylene and ethylene bridges were inserted into the molecule of endothelin-1 (ET-1) as other possible isosteric replacements of its outer disulfide linkage. The [1-deamino-1-carba]ET-1, [1-deamino-15-carba]ET-1 and [1-deamino-1,15-dicarba]ET-1 were synthesized either by a fragment condensation of protected cyclic pentadecapeptides with carboxy-terminal hexapeptides of the endothelin-1 sequence or by step-wise coupling on polymer support of the entire henicosapeptide sequences from carboxy-terminus. The analogues were devoid of uterotonic activity in comparison with the parent ET-1.
Studies Toward an Asymmetric Synthesis of CP-263,114 and CP-225,917
Authors: Devaux Jean-François , O'Neil Steven V. , Guillo Nathalie , Paquette Leo A.
Published: July 2002

An enantioselective approach to construction of the complex framework of the CP compounds is presented. The synthesis relies on initial elaboration of the two sidechains. The "upper" appendage was asymmetrically dihydroxylated with both AD-mix reagents in order to lend flexibility to the scheme and provide the necessary handle for evolving the additional stereogenic centers. These fragments were linked to benzoic acidviaBirch reduction-alkylation and subsequent cuprate addition. A series of functionalization reactions including dissolving metal reduction, Claisen rearrangement, iodolactonization, regioselective epoxide cleavage-oxidation, and intramolecular Wadsworth-Emmons cyclization took advantage of highly efficient stereocontrol. However, this flexibility was thwarted when deprotonation of a penultimate intermediate failed to be regioselective in the proper direction.
Versatile Enantioselective Synthesis of Four Diastereomers of Serricornin, a Sex Pheromone of the Cigarette Beetle, Using the SAMP/RAMP-Hydrazone Method
Authors: Job Andreas , Nagelsdiek René , Enders Dieter
Published: July 2002

Serricornin is a female-produced sex pheromone of the cigarette beetle (Lasioderma serricorne), which is a pest of dried foodstuffs and tobacco. We report a versatile and short synthesis of all possible 6,7-syn-isomers of serricornin, including the natural isomer. Starting from the SAMP and RAMP derivatives of diethyl ketone we obtained four different enantiopure and diastereomerically pure serricornins. The main advantage of this method is that only a single kind of chiral starting material is needed for the construction of three stereogenic centers. During the synthesis further useful intermediates including (R)- and (S)-1-benzyloxy-2-methylpentan-3-one (4) and (2S,3R)- and (2R,3S)-1-iodo-3-(methoxy- methoxy)-2-methylpentane (9) were obtained.
Homologation of O-Acetylated Methyl Hexopyranosides with a Grignard C1 Reagent
Authors: Grzeszczyk Barbara , Zamojski Aleksander
Published: July 2002

Three methyl 2,3,4-tri-O-acetyl-α-D-hexopyranosides of the manno, gluco, and galacto configuration were oxidized to the corresponding methyl hexodialdo-1,5-pyranosides and then reacted with allyloxymethylmagnesium chloride. Methyl heptopyranosides of the D- and L-glycero-α-D-manno-, -α-D-gluco, and -α-D-galacto configuration were obtained in moderate yields. Migration of the 4-O-acetyl group in the products was observed. An interpretation of the results was proposed.
Preparation of Intermediates for Fluorinated Lignans by Conjugated and Tandem Additions on 3-Fluorofuran-2(5H)-one
Authors: Kvíčala Jaroslav , Vlasáková Růžena , Plocar Jakub , Paleta Oldřich , Pelter Andrew
Published: July 2002

Two syntheses of 3-fluorofuran-2(5H)-one (1) based on Wittig-Horner reaction of ethyl (diethoxyphosphoryl)fluoroacetate (15) with 2-oxoethyl acetate (16) or on transformation of D-erythronolactone (10) are given. 3-Fluorofuran-2(5H)-one (1) and ethyl 2-fluorobut- 2-enoate (2) undergo conjugate addition with soft nucleophiles based on arene- carboxaldehyde dithioacetals 7 to form 2-fluorolactones 3 and 2-fluoroalkanoates 4. Intermediate enolates can be trapped in the sense of tandem addition with arenecarboxaldehydes 8 or (arylmethyl)bromides 9 to form intermediates 5 and 6 for fluorolignans. Although the conjugate addition proceeds with low stereoselectivity yielding mixture of both diastereoisomers, the electrophile in tandem addition attacks the intermediary fluoroenolate exclusively anti to its bulky β-substituent in good accord with non-fluorinated furan- 2(5H)-ones.
Crystal Structures of Dihydro-α-ergokryptine and Dihydro-β-ergokryptine Mesylates
Authors: Čejka Jan , Kratochvíl Bohumil , Jegorov Alexandr , Cvak Ladislav
Published: July 2002

The absolute crystal structures of two related ergot alkaloids dihydro-α-ergokryptine mesylate (1) monohydrate ethanol solvate and dihydro-β-ergokryptine mesylate (2) monohydrate methanol solvate have been determined by X-ray diffraction and compared with the published structures of dihydroergocristine mesylate (3) monohydrate and dihydroergotamine mesylate (4) monohydrate.
The Bender Equation of State and Virial Coefficients
Authors: Malijevský Anatol , Hujo Tomáš
Published: July 2002

The second and third virial coefficients calculated from the Bender equation of state (BEOS) are tested against experimental virial coefficient data. It is shown that the temperature dependences of the second and third virial coefficients as predicted by the BEOS are sufficiently accurate. We conclude that experimental second virial coefficients should be used to determine independently five of twenty constants of the Bender equation. This would improve the performance of the equation in a region of low-density gas, and also suppress correlations among the BEOS constants, which is even more important. The third virial coefficients cannot be used for the same purpose because of large uncertainties in their experimental values.
Urinary calcium excretion in enterally fed disabled children
Authors: Shetty A K , Carlin J , Mughal M Z
Published: July 2002

The urine calcium/creatinine (Ca/Cr) ratio was measured in 17 enterally tube fed disabled children. Urine Ca/Cr ratios were inversely related to dietary calcium intake in immobile children (r = −0.57, p < 0.05) but not in those who were able to stand or walk (mobile children) (r = 0.4, p = 0.51). None of the subjects had evidence of nephrocalcinosis or renal calculi detectable by renal ultrasonography.
A comparison of lactate concentration in plasma collected from the toe, ear, and fingertip after a simulated rowing exercise
Authors: Forsyth J J , Farrally M R
Published: July 2002

Objective—To examine the validity of using blood taken from the toe for the assessment of plasma lactate concentration in rowers. To achieve this, values were compared with those taken from the fingertip and earlobe.

Methods—Nine subjects exercised at two separate submaximum workloads on the Concept II rowing ergometer. The loads, each lasting four minutes, elicited mean (SD) heart rate responses of 160.1 (8.5) and 180.1 (5.7) beats/min, which corresponded to 76.4 (6.1)% and 91.9 (4.7)% of the estimated heart rate maximum of the subjects. Blood was simultaneously removed after the cessation of exercise by three experimenters and was analysed for plasma lactate concentration.

Results—At 76.4% of estimated heart rate maximum, the mean (SD) plasma lactate concentrations sampled from the fingertip, toe, and earlobe were 6.36 (1.58), 5.81 (1.11), and 5.29 (1.24) mmol/l respectively. At 91.9% of estimated heart rate maximum, respective values were 8.81 (2.30), 8.53 (1.37), and 8.41 (2.35) mmol/l. No significant differences (p>0.05) were found between any of the sites at either work intensity.

Conclusions—The toe may offer a practical alternative for assessing the concentration of lactate during rowing, having the advantage that repeated blood samples can be removed without interruption of the rowing action.
Isokinetic performance and shoulder mobility in elite volleyball athletes from the United Kingdom
Authors: Wang Hsing-Kuo , Macfarlane Alison , Cochrane Tom
Published: July 2002

Objectives—To evaluate the differences in strength and mobility of shoulder rotator muscles in the dominant and non-dominant shoulders of elite volleyball players.

Methods—Isokinetic muscle strength tests were performed at speeds of 60 and 120°/s, and shoulder mobility was examined in ten players from the England national men's volleyball squad. The subjects also completed a questionnaire that included a visual prompt and analogue pain scale.

Results—The range of motion of internal rotation on the dominant side was less than that on the non-dominant side (p<0.01). The average peak strength at 60°/s external eccentric contraction was lower than that of internal concentric contraction in the dominant arm, but was higher in the non-dominant arm. Six of the ten subjects reported a shoulder problem, described as a diffuse pain located laterally on the dominant shoulder.

Conclusions—These elite volleyball players had a lower range of motion (internal rotation) and relative muscle imbalance in the dominant compared with the non-dominant shoulder.
Computerised cognitive assessment of athletes with sports related head injury
Authors: Collie A , Darby D , Maruff P
Published: July 2002

Professional and amateur participants in many sports are at risk of brain injury caused by impact with other players or objects. In many cases, mild cognitive deficits may persist after the common neurological signs of brain injury have passed. In recent years, the athlete's cognitive status after concussion has been measured with conventional “paper and pencil” neuropsychological tests. However, such tests are not ideal for sporting settings, as they are designed for the detection of gross cognitive impairments at a single assessment, not for the identification of mild cognitive deficits on repeated assessment. A number of computerised cognitive assessment tests and test batteries have been developed over the past two decades. These batteries offer major scientific and practical advantages over conventional neuropsychological tests which make them ideal for the assessment of cognitive function in sportspeople. This review first describes the problems associated with cognitive assessment of people with sports related cognitive deficits, and then critically examines the utility of conventional neuropsychological and computerised cognitive tests in sporting settings.
The VISA-A questionnaire: a valid and reliable index of the clinical severity of Achilles tendinopathy
Authors: Robinson J M , Cook J L , Purdam C , Visentini P J , Ross J , Maffulli N , Taunton J E , Khan K M
Published: July 2002

Background—There is no disease specific, reliable, and valid clinical measure of Achilles tendinopathy.

Objective—To develop and test a questionnaire based instrument that would serve as an index of severity of Achilles tendinopathy.

Methods—Item generation, item reduction, item scaling, and pretesting were used to develop a questionnaire to assess the severity of Achilles tendinopathy. The final version consisted of eight questions that measured the domains of pain, function in daily living, and sporting activity. Results range from 0 to 100, where 100 represents the perfect score. Its validity and reliability were then tested in a population of non-surgical patients with Achilles tendinopathy (n = 45), presurgical patients with Achilles tendinopathy (n = 14), and two normal control populations (total n = 87).

Results—The VISA-A questionnaire had good test-retest (r= 0.93), intrarater (three tests,r= 0.90), and interrater (r= 0.90) reliability as well as good stability when compared one week apart (r= 0.81). The mean (95% confidence interval) VISA-A score in the non-surgical patients was 64 (59–69), in presurgical patients 44 (28–60), and in control subjects it exceeded 96 (94–99). Thus the VISA-A score was higher in non-surgical than presurgical patients (p = 0.02) and higher in control subjects than in both patient populations (p<0.001).

Conclusions—The VISA-A questionnaire is reliable and displayed construct validity when means were compared in patients with a range of severity of Achilles tendinopathy and control subjects. The continuous numerical result of the VISA-A questionnaire has the potential to provide utility in both the clinical setting and research. The test is not designed to be diagnostic. Further studies are needed to determine whether the VISA-A score predicts prognosis.
Concurrent occurrence of gastric adenocarcinoma and duodenal neuroendocrine cell carcinoma: a composite tumour or collision tumours ?
Authors: Fukui H , Takada M , Chiba T , Kashiwagi R , Sakane M , Tabata F , Kuroda Y , Ueda Y , Kawamata H , Imura J , Fujimori T
Published: July 2002

BACKGROUND

Neuroendocrine cell (NEC) carcinoma is occasionally accompanied by adenocarcinoma but the relationship between these two morphologically distinct tumours is unclear. Two hypotheses have arisen regarding the mechanism for the association of adenocarcinoma and NEC carcinoma. One is that both are derived from a common multipotential epithelial stem cell. The second hypothesis is that adenocarcinoma and NEC carcinoma arise from a multipotential epithelial stem cell and a primitive NEC, respectively.

AIMS

To elucidate the relationship between the two histologically distinct tumours, adenocarcinoma of the stomach and NEC carcinoma of the duodenum.

PATIENT/METHODS

We present a case in which the tumour extended across the pyloric ring, the gastric portion of which revealed adenocarcinoma while the duodenal portion showed argyrophil NEC carcinoma. The two histologically distinct lesions of the tumour were examined by immunohistochemistry and genetic analysis of p53.

RESULTS

The gastric region was negative for chromogranin A staining but positive for carcinoembryonic antigen (CEA) staining. In contrast, the duodenal region was positive for chromogranin A but negative for CEA. All tumour regions showed a point mutation in p53 gene at exon 7 (GGC (glycine)→GTC (valine) at codon 245). The distal portion of the duodenal tumour showed an additional point mutation inp53 gene at exon 5 (GCC (alanine)→GTC (valine) at codon 129).

CONCLUSIONS

The two histologically distinct tumours, adenocarcinoma of the stomach and NEC carcinoma of the duodenum, appear to be derived from a common epithelial cell.
Polymicrobial tenosynovitis withPasteurella multocidaand other Gram negative bacilli after a Siberian tiger bite
Authors: Isotalo P A , Edgar D , Toye B
Published: July 2002

Mammalian bites present a considerable clinical problem because they are often associated with bacterial infections.Pasteurella multocida is a microorganism that commonly infects both canine and small feline bites. Zoonotic infections developing after large feline bites have been recognised, although their reports are limited. We describe a 35 year old man who was bitten by a Siberian tiger and who developed infectious tenosynovitis secondary to P multocida, Bergeyella (Weeksella) zoohelcum, and Gram negative bacteria most like CDC group EF-4b and comamonas species. The latter three bacteria have not been isolated previously from large feline bite wounds.
Psychiatric disorders and fitness to drive
Authors: Niveau Gérard , Kelley-Puskas Melissande
Published: July 2002

Objective—In Switzerland, as in some other European countries, medical doctors may breach patient confidentiality and report to police authorities any patient who seems prone to automobile accidents or traffic violations. The aim of this study was to see if those patients reported to authorities actually represent a higher risk than drivers not reported to the police.

Design—This study was designed following a case-control study comparing the characteristics of a group of psychiatric patients who were reported to authorities for preventive purposes, with the characteristics of another group of people who had disorders that were noticed at the time of an accident or traffic violation.

Results—The results show that medical doctors tended to report male patients, patients with a low level of education, and patients with a severe psychiatric background. The subjects of the control group, who had often been involved in accidents or committed traffic violations in the past, did not possess these characteristics.

Conclusions—The breach of medical confidentiality by doctors in reporting to authorities patients who are allegedly at risk is ethically questionable as long as the evaluation of driving performance does not rely on objective bases.
Support for ethical dilemmas in individual cases: experiences from the Neu-Mariahilf hospital in Goettingen
Authors: Simon Alfred
Published: July 2002

Prompted by a recommendation of the two Christian hospital associations in Germany, the Neu-Mariahilf Hospital in Goettingen set up a health ethics committee in autumn 1998. It is the committee's task to give support to staff members, patients and their relatives in individual cases where ethical dilemmas arise. The following article descibes the committee's work by means of three cases.
Imagination and medical education
Authors: Evans Donald
Published: July 2002

Rival and apparently exclusive views have been canvassed about the instrumental use of the humanities in medical education. The novel is seen as offering exemplifications of moral principles on the one hand, whilst on the other such an approach is said to miss the essence of reading a novel by misrepresenting the engagment of the reader. The use of the humanities in medicine as a stimulus to reflective practice is presented as a preferable account which recognises that there is truth in each of the former views.
Literary narrative in medical practice
Authors: Kottow M , Kottow A
Published: July 2002

It is generally accepted that the practice of medicine could be improved by turning to the humanities in general, and to narrative and text interpretation in particular. Neverthless, there is hardly any agreement as to the nature of the clinical text, whether it be the patient's narrative that needs to be richly understood, or the patient as patient who must be both personally and clinically deciphered.

We suggest that literary narratives depicting medical situations might serve as testimonials of the way medicine has or is being practised in a variety of social settings, and of the ways patients experience disease and medical care. By reading these texts, health care professionals could compare the situations and values involved in such narratives with current medical practices, thus perceiving how clinical encounters have changed and improved or, perhaps, continue to carry a burden of past flaws.
Amiodarone-induced thyroid disorders: a clinical review
Authors: Loh Keh-Chuan
Published: July 2002

Although amiodarone is regarded as a highly effective anti-arrhythmic agent, its use may lead to alterations in thyroid gland function and/or thyroid hormone metabolism, partly because of its rich iodine content. Patients treated with amiodarone may manifest altered thyroid hormone profile without thyroid dysfunction, or they may present with clinically significant amiodarone-induced hypothyroidism or amiodarone-induced thyrotoxicosis. The former results from the inability of the thyroid to escape from the Wolff-Chaikoff effect. It prevails in areas with high dietary iodine intake, and it is readily managed by discontinuation of amiodarone or thyroid hormone replacement. Amiodarone-induced thyrotoxicosis occurs more frequently in areas with low iodine intake; it may arise from iodine-induced excessive thyroid hormone synthesis (type I) or destructive thyroiditis with release of preformed hormones (type II). Type I should be treated with thionamides alone or in combination with potassium perchlorate, whereas type II benefits from treatment with glucocorticoids. Surgery may be a feasible option for patients who require long-term amiodarone treatment.
Posterior leukoencephalopathy syndrome
Authors: Garg R K
Published: July 2002

Posterior leukoencephalopathy syndrome is a newly recognised brain disorder that predominantly affects the cerebral white matter. Oedematous lesions particularly involve the posterior parietal and occipital lobes, and may spread to basal ganglia, brain stem, and cerebellum. This rapidly evolving neurological condition is clinically characterised by headache, nausea and vomiting, seizures, visual disturbances, altered sensorium, and occasionally focal neurological deficit. Posterior leukoencephalopathy syndrome is often associated with an abrupt increase in blood pressure and is usually seen in patients with eclampsia, renal disease, and hypertensive encephalopathy. It is also seen in the patients treated with cytotoxic and immunosuppressive drugs such as cyclosporin, tacrolimus, and interferon alfa. The lesions of posterior leukoencephalopathy are best visualised with magnetic resonance (MR) imaging. T2 weighted MR images, at the height of symptoms, characteristically show diffuse hyperintensity selectively involving the parieto-occipital white matter. Occasionally the lesions also involve the grey matter. Computed tomography can also be used satisfactorily to detect hypodense lesions of posterior leukoencephalopathy. Early recognition of this condition is of paramount importance because prompt control of blood pressure or withdrawal of immunosuppressive agents will cause reversal of the syndrome. Delay in the diagnosis and treatment can result in permanent damage to affected brain tissues.
Whose standard is it, anyway? How the tobacco industry determines the International Organization for Standardization (ISO) standards for tobacco and tobacco products
Authors: Bialous Stella A , Yach Derek
Published: July 2002

OBJECTIVE

To describe the extent of the tobacco industry involvement in establishing international standards for tobacco and tobacco products and the industry influence on the International Organization for Standardization (ISO).

METHODS

Analysis of tobacco industry documents made public as part of the settlement of the Minnesota Tobacco Trial and the Master Settlement Agreement. Search words included “ISO”, “CORESTA”, “Barclay”, “compensation and machine smoking”, “tar and nicotine deliveries”, and the name of key players, in different combinations.

RESULTS

It is clear that the tobacco industry, through the Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA), play a major role in determining the scientific evidence and suggesting the standards that are eventually adopted as international standards for tobacco and tobacco products in several areas, including the measurement of cigarette tar and nicotine yield.

CONCLUSIONS

ISO's tobacco and tobacco products standards are not adequate to guide tobacco products regulatory policies, and no health claims can be made based on ISO's tobacco products standards. There is an urgent need for tobacco control advocates and groups worldwide to be more involved with the work of the ISO, both directly and through their national standardisation organisations.
Policy makers' perspectives on tobacco control advocates' roles in regulation development: Table 1
Authors: Montini Theresa , Bero Lisa A
Published: July 2002

OBJECTIVE

To identify, from policy makers' perspectives, strategies that enhance tobacco control advocates' effectiveness in the regulatory arena.

DESIGN

Key informant interview component of a comparative case study of regulatory agencies in the USA.

SUBJECTS

Policy makers involved in the development of four regulatory tobacco control policies (three state and one federal).

METHODS

Interviews of policy makers, field notes, and deliberation minutes were coded inductively.

RESULTS

Policy makers considered both written commentary and public testimony when developing tobacco control regulations. They triaged written commentary based upon whether the document was from a peer reviewed journal, a summary of research evidence, or from a source considered credible. They coped with in-person testimony by avoiding being diverted from the scientific evidence, and by assessing the presenters' credibility. Policy makers suggested that tobacco control advocates should: present science in a format that is well organised and easily absorbed; engage scientific experts to participate in the regulatory process; and lobby to support the tobacco control efforts of the regulatory agency.

CONCLUSIONS

There is an important role for tobacco control advocates in the policy development process in regulatory agencies.
Second hand smoke and risk assessment: what was in it for the tobacco industry?
Authors: Hirschhorn Norbert , Bialous Stella Aguinaga
Published: July 2002

OBJECTIVE

To describe how the tobacco industry attempted to trivialise the health risks of second hand smoke (SHS) by both questioning the science of risk assessment of low dose exposure to other environmental toxins, and by comparing SHS to such substances about which debate might still exist.

METHODS

Analysis of tobacco industry documents made public as part of the settlement of litigation in the USA (Minnesota trial and the Master Settlement Agreement) and available on the internet. Search terms included: risk assessment, low dose exposure, and the names of key players and organisations.

RESULTS/CONCLUSION

The tobacco industry developed a well coordinated, multi-pronged strategy to create doubt about research on exposure to SHS by trying to link it to the broader discussion of risk assessment of low doses of a number of toxins whose disease burden may still be a matter of scientific debate, thus trying to make SHS their equivalent; and by attempting, through third party organisations and persons, to impugn the agencies using risk assessment to establish SHS as a hazard.
Application of a rating system to state clean indoor air laws (USA)
Authors: Chriqui J F , Frosh M , Brownson R C , Shelton D M , Sciandra R C , Hobart R , Fisher P H , el Arculli R , Alciati M H
Published: July 2002

Objective: To develop and implement a system for rating state clean indoor air laws.

Design: The public health interest of state clean indoor air laws is to limit non-smoker exposure to environmental tobacco smoke (ETS). Current estimates of health risks and methods available for controlling ETS provided a framework for devising a ratings scale. An advisory committee applied this scale to each of seven site specific smoking restrictions and two enforcement related items. For each item, a target score of +4 was identified. The nine items were then combined to produce a summary score for each state. A state that achieved the target across all nine items would receive a summary score of 36 points and be eligible to receive an additional 6 points for exceeding the target on six of the nine items, resulting in a maximum summary score of 42 points. Individual scores were also adjusted to reflect state level preemption measures. Each state's law was evaluated annually from 1993 through 1999.

Setting: USA.

Main outcome measure: A summary score measuring the extensiveness of the state's clean indoor air law.

Results: State laws restricting smoking in the seven individual locations of interest were relatively weak. The overall mean score across the location restrictions ranged from 0.72 in 1993 to 0.98 in 1999. Mean scores were higher for the enforcement items than for the location restrictions. Summary scores ranged from 0 to 20 in 1993 and 0 to 31 in 1994 through 1999. Average summary scores ranged from 8.71 in 1993 to 10.98 in 1999. By the end of 1999, scores increased for 22 states; however, between 1995 and 1997 there were no changes in the summary scores. Three states scored zero points across all years. From 1993 through 1999, there was a 41% increase in the number of states that had in place state level preemption measures.

Conclusion: The number of newly enacted state clean indoor air laws has remained relatively stagnant since 1995. With a few exceptions, as of the end of 1999, progress in enacting state laws to meet specified public health targets for reducing exposure to ETS was relatively low. Thus, state laws in the USA provide, on average, only minimal protection in specified areas and, given the increase in preemption, are increasingly undermining those passed in localities.