bluuebunny/crossref_metadata_2025 huggingface dataset:
Redirecting Retroviral Tropism by Insertion of Short, Nondisruptive Peptide Ligands into Envelope
Authors: Gollan Timothy J. , Green Michael R.
Published: July 2002

A potentially powerful approach for in vivo gene delivery is to target retrovirus to specific cells through interactions between cell surface receptors and appropriately modified viral envelope proteins. Previously, relatively large (>100 residues) protein ligands to cell surface receptors have been inserted at or near the N terminus of retroviral envelope proteins. Although viral tropism could be altered, the chimeric envelope proteins lacked full activity, and coexpression of wild-type envelope was required for production of transducing virus. Here we analyze more than 40 derivatives of ecotropic Moloney murine leukemia virus (MLV) envelope, containing insertions of short RGD-containing peptides, which are ligands for integrin receptors. In many cases pseudotyped viruses containing only the chimeric envelope protein could transduce human cells. The precise location, size, and flanking sequences of the ligand affected transduction specificity and efficiency. We conclude that retroviral tropism can be rationally reengineered by insertion of short peptide ligands and without the need to coexpress wild-type envelope.
A Monte Carlo Study of Insoluble Block Orientations in Swollen Cores of Multimolecular Block Copolymer Micelles
Authors: Limpouchová Zuzana , Procházka Karel
Published: July 2002

Conformations of tethered chains in restricted spherical volumes with an increasing radius were studied by Monte Carlo simulations. Simulations were performed on a tetrahedral lattice at relatively high densities of the occupied lattice sites. A simultaneous self-avoiding walk of all tethered chains creates the starting conformations of the multi-chain system which are futher equilibrated by a modified algorithm similar to that of Siepmann and Frenkel. In this paper, only a geometric excluded volume effect of segments is considered. Selectively chosen series of data for changing numbers of chains, N, their lengths, L, and radii of the sphere, R, give information on the system behavior under various conditions. In this part of our systematic study of tethered chains in constrained volumes, we present angular distribution functions of the end-to-end, end-to-gravity center distances, etc. for system studied in previous paper. The second class of studied conformational characteristics are the distributions of projections of the end-to-end vectors into the selected directions (i.e. the radial direction and the direction of the first-to-second polymer segment connection).
The Crystal and Molecular Structure of Butorphanol Hydrogen Tartrate
Authors: Jegorov Alexandr , Sobotík Roman , Pakhomova Svetlana , Ondráček Jan , Novotný Jiří , Hušák Michal , Kratochvíl Bohumil
Published: July 2002

The structure of butorphanol hydrogen tartrate {(9R,13S,14S)-(-)-17-(cyclobutylmethyl)morphinan-3,14-diol (2S,3S)-(-)-hydrogen tartrate} (C21H29NO2 .C4H6O6) was solved by direct methods and refined anisotropically to the R value of 0.029 for 2 069 observed reflections. The title morphine analogue crystallizes in the triclinic space group P1 with lattice parameters a = 7.620(1), b = 9.140(1), c = 9.591(1) Å, α = 105.48(1), β = 112.91(1), γ = 84.29(1)°, Z = 1. The butorphanol B ring possesses the 3E envelope conformation with small 3H2 distortion, C and D rings have a regular chair conformation. The intramolecular N17-H17...O2 hydrogen bond is observed in crystal structure of the title compound. The butorphanol and hydrogen tartrate molecules are joined together by means of O2-H(O2)...O7, O1-H(O1)...O7' and O3-H(O3)...O8" hydrogen bonds to form networks.
Isomorphic Co-Crystallization of Ammonium and Rubidium Bromocarnallites
Authors: Christov Christomir , Balarew Christo , Tepavitcharova Stefka
Published: July 2002

The solubility isotherm of the system NH4Br.MgBr2.6 H2O - RbBr.MgBr2.6 H2O - H2O has been investigated at 75 °C and formation of a continuous series of mixed crystals is established. The factors determining the values of the distribution coefficients of the components between the crystalline and liquid phases are discussed.
Reactions of 2,4,4,6-Tetraaryl-4H-thiopyrans with Chlorine: An Unusual Reaction Route
Authors: Šebek Pavel , Kroulík Jiří , Sedmera Petr , Havlíček Vladimír , Kuthan Josef
Published: July 2002

2,4,4,6-Tetraaryl-4H-thiopyrans Ia - Ig react smoothly with carbon disulfide solution of chlorine already at 0 °C yielding the corresponding 3,5-dichloro derivatives IIa - IIg. With longer reaction time and temperature raised to 20 °C, the 4H-thiopyrans Ia - Ie gave exclusively the trichloro derivatives IIIa - IIIe whereas If and Ig underwent a nonselective chlorination leading to multicomponent mixtures of products. Isolation of sulfoxides IVa and IVe from the chlorination of Ia and Ie (upon hydrolysis of the reaction mixture) allowed us to formulate the reaction mechanism for the formation of compounds type III. 1H, 13C NMR, and mass spectra of the prepared compounds are discussed in detail.
Equilibria of Reactions Between Nitrogen Oxides and Calcium Hydroxide
Authors: Erdös Emerich , Mocek Karel
Published: July 2002

A general analysis of chemical equilibria in a system consisting of the gaseous nitrogen monoxide, nitrogen dioxide, water vapor, carbon dioxide, oxygen, and the solid calcium hydroxide is carried out with respect to the equilibrium partial pressures of nitrogen oxides. The conditions are defined, under which the calcium hydroxide is transformed to the calcium carbonate. The corresponding equilibrium equations are derived for all nine regions of existence of described system. The results are illustrated graphically and discussed from the point of removing the nitrogen oxides from waste gases.
Crystal Structure of the Adduct Hexahydroxotelluric Acid-Disodium Ethylenediaminetetraacetate-Water (1/1/2)
Authors: Císařová Ivana , Podlahová Jana , Podlaha Jaroslav
Published: July 2002

The title compound crystallizes in the form of racemic twins of hexagonal symmetry from slightly acidic aqueous solutions containing H6TeO6 and Na2H2edta in a broad range of molar ratios. The crystals are of excellent quality and high diffraction power, thus enabling the structure determination with a precission not routinely attainable by conventional single crystal X-ray diffraction (R = 0.015 at room temperature). The building units of the structure, held together by a system of hydrogen bonds, are the octahedral Te(OH)6 molecule, the H2edta2- anion with protonated nitrogens, two water molecules and two sodium cations surrounded by ten oxygens in the O4Na(mi-O)2NaO4 moiety of irregular geometry.
Lithium and Ammonium Selenates
Authors: Havlíček David , Mička Zdeněk , Boublíková Radka
Published: July 2002

The Li2SeO4-H2SeO4-H2O and (NH4)2SeO4-Li2SeO4-H2O systems were studied at 30 °C to obtain data for determining the conditions of formation of the compound (NH4)4LiH3(SeO4)4, whose characteristics correspond to those of substances possessing significant dielectric properties. The results were used to construct the pseudoternary LiNH4SeO4-NH4HSeO4 -H2O section in the quaternary system, which gave evidence that only (NH4)3H(SeO4)2 forms in the crystallization region of the compound sought. Attention was also paid to lithium ammonium selenate, which was characterized by its X-ray, spectral, and thermal analysis data.
Synthesis of Heterocyclic Ketene N,S-Acetals and Their Reactions with α,β-Unsaturated Nitriles
Authors: El-Shafei Ahmed K. , El-Saghier Ahmed M. M. , Soliman Ahmed M.
Published: July 2002

Substituted 3H-pyrido[2,1-b]benzoxazoles and 3H-pyrido[2,1-b]benzothiazoles were prepared by base catalyzed cycloaddition of benzylidenemalonitrile with benzoxazolylidene- or benzothiazolylidenepentane-1,3-dione.
Liquid-Liquid Phase Separation in Multicomponent Polymer Systems. XXVI. Blends of Two Polydisperse Polymers
Authors: Šolc Karel , Koningsveld Ronald
Published: July 2002

A method for computing phase diagrams of polydisperse A/B polymer blends is proposed, based on Flory-Huggins-Staverman thermodynamics, and employed to obtain cloud-point curves (CPCs), shadow curves, spinodals and coexistence curves for a series of systems. Often bimodal CPCs and shadow curves result, even for systems with a concentration-independent interaction parameter g. The importance of coexistence curves, as opposed to CPCs, for judging the A/B miscibility, recently observed in polydisperse blends, is confirmed in this study. Particular attention is here paid to the critical state. Analytical relations are derived for the critical point (CP) and the critical slopes of the CPC and shadow curve, as well as for the criterion of CP stability, all in terms of various molar-mass averages of A and B. The latter criterion then yields conditions for the existence of heterogeneous double CPs and triple CPs, important as markers announcing the proximity of a three-phase region. Interestingly, the sign of the critical CPC slope depends solely on the relative magnitude of the rz/rw ratios for the two polymers A and B. Hence, a CP located at the CPC's top should not be interpreted as a proof of both polymers' monodispersity. The validity of derived analytical relations is confirmed by numerically computed phase diagrams.
Cytochrome P-450 and Peroxidase Oxidize Detoxication Products of Carcinogenic Aristolochic Acids (Aristolactams) to Reactive Metabolites Binding to DNA in vitro
Authors: Stiborová Marie , Frei Eva , Schmeiser Heinz H. , Wiessler Manfred
Published: July 2002

We report the analysis of DNA adducts formed from aristolactams I and II, which are the final metabolites derived from carcinogenic aristolochic acids in vivo, after their oxidation by microsomal cytochrome P-450 and horseradish peroxidase in vitro. DNA adducts were detected and quantified using the nuclease P1-enhanced variation of the 32P-postlabeling assay. Quantitative analysis revelead that the extent of modification of DNA by aristolactams activated by peroxidase was more than one order of magnitude higher than for activation by microsomal cytochrome P-450. Peroxidase catalyzes the formation of active oxygen in the presence of NADH, H2O2 and aristolactams. Aristolactams are also oxidized by mammalian peroxidase prostaglandin H synthase. The possible role of aristolactams in carcinogenesis induced by aristolochic acid is discussed.
Kinetic Study of the Oxidation of Glycine by Permanganate Ions in Acid Medium
Authors: Insausti Maria J. , Mata-Pérez Fernando , Alvarez-Macho Maria P.
Published: July 2002

The oxidation of glycine by permanganate ions was studied in a buffered solution at pH 2.2. An autocatalytic reaction was observed, autocatalyzed by a soluble form of Mn(IV). Autocatalytic S-shaped kinetic curves were obtained by the spectrophotometric method and characterized by the time ti vs concentration in the inflection point.
Conformation of 5-Amino-5-deoxypentonolactams
Authors: Kefurt Karel , Havlíček Jaroslav , Hamerníková Michaela , Kefurtová Zdeňka , Votavová Hana
Published: July 2002

Four configuration isomers of 5-amino-5-deoxy-D-pentonolactam 1a-4a and their tri-O-acetyl derivatives 1b-4b were studied using NMR and CD spectroscopy. For all compounds chemical shifts of the 1H and 13C nuclei as well as of vicinal coupling constants were obtained. Comparison of the observed 3J(H,H) with those calculated for various conformations by a modified Karplus relationship led to the assignment of predominant conformation 3H4(D) or 4H3(D) to the lactams 1a-4a and 1b-4b in solution. The most important factor for determining the conformation seems to be the pseudoequatorial position of the substituent on the carbon next to the carbonyl group. The results of the CD spectra of the lactams 1a-4a in water, interpreted according to the currently used rules, agreed with the NMR results.
Adsorption and Oxidation of Thiosulfate on a Platinum Electrode in Acid Solution
Authors: Loučka Tomáš
Published: July 2002

The adsorption of thiosulfate on a platinum electrode was measured at the open circuit potential. A monolayer of the adsorption products covers the electrode at lower thiosulfate concentrations. The charge used up during the reduction of the monolayer roughly corresponds to 0.5 electron per surface site (e.p.s.), the charge used up during the oxidation of the monolayer after reduction corresponds approximately to 4 e.p.s. Multiple adsorbed layers, which are presumably constituted mainly by adsorbed sulfur, build up at higher thiosulfate concentrations. The amount of the adsorbed substance increases with increasing thiosulfate concentration and time of adsorption. Desorption from the surface coated by multiple layers can take place in supporting electrolyte solution. The build-up of multiple adsorbed sulfur layers also takes place during adsorption from solutions of colloidal sulfur.
The Template Synthesis and Characterization of New Mono- and Dinuclear Podand Schiff Base Complexesof Scandium Group Elements
Authors: Luks Emilia , Radecka-Paryzek Wanda
Published: July 2002

The partial Schiff base condensation reactions between 2,6-diacetylpyridine and 1,3-phenylenediamine in the presence of scandium(III), yttrium(III) and lanthanum(III) ions as template agents afford new mono- and dinuclear hexadentate complexes of podate type, depending on the molar ratio of starting materials used in the synthesis. They were characterized by IR, UV-VIS, 1H NMR, and mass spectral data as well as by thermogravimetric and elemental analyses.
Catalytic Activity of Cu Ion-Exchanged Metalloaluminophosphates in NO Decomposition
Authors: Dědeček Jiří , Vondrová Alena , Čejka Jiří
Published: July 2002

NO decomposition was investigated over Cu ion-exchanged aluminophosphate molecular sieve catalysts. Cu ions in cationic positions balanced by one framework negative charge in the metalloaluminophosphates of AlPO-5 and AlPO-11 structures exhibited catalytic activity in NO decomposition comparable with that of Cu-ZSM-5. No catalytic activity of the Cu ions incorporated during synthesis of molecular sieves into the framework in tetrahedral positions (CuAlPO-11) was observed. The catalytic activity of Cu-MeAlPO-5 and Cu-MeAlPO-11 was observed with various divalent metal ions of the MeAlPO-5 and MeAlPO-11 frameworks (Me = Zn, Mg, Fe, Co) and also with Cu exchanged SAPO-5 molecular sieves. The Cu-MeAlPO-5 and Cu-MeAlPO-11 catalysts differed only in the temperature of the maximum observed catalytic activity.
Transfer of Charge in a Particulate Iron-Electrolyte System
Authors: Gál Miroslav F. , Gálová Miriam , Turoňová Andrea
Published: July 2002

Mechanism of the charge transfer through a heterogeneous system consisting of Fe powder particles suspended in nickel-plating electrolyte was studied in the regime of electrolysis. Conductivity and impedance spectra were used to elucidate the contribution of solid particles to the charge transfer through the cell. Combined short-circuit and collision mechanism takes place in low-density suspensions. A complete elucidation of the mechanism is complicated by the presence of powder particles of three groups: particles carrying the charge, uncharged particles representing just a barrier to the charge transfer and particles passivated during the electrolysis by adsorption of an isolating layer of Fe and Ni hydroxocomplexes. The formation of powder aggregates in high-density suspensions was indirectly evidenced.
Synthesis, Crystal Structure and Magnetic Properties of Novel Complex [μ-(NC)-Fe(CN)3(NO)-μ-(CN)-Cu(ept)]n·4nH2O (ept = N-(2-Aminoethyl)propane-1,3-diamine)
Authors: Smékal Zdeněk , Kameníček Jiří , Svoboda Ingrid , Escuer Albert
Published: July 2002

The novel complex [μ-(NC)-Fe(CN)3(NO)-μ-(CN)-Cu(ept)]n·4nH2O (ept = N-(2-aminoethyl)- propane-1,3-diamine) was obtained by the reaction of Cu(ClO4)2·6H2O with N-(2-amino- ethyl)propane-1,3-diamine and Na2[Fe(CN)5NO]·2H2O in water. This compound was characterized by IR, UV-VIS and EPR spectroscopies and magnetic measurement. Single-crystal X-ray structure analysis revealed that the title complex has a one-dimensional polymeric structure containing hexacoordinate iron(II) with five cyanide ligands (two of them, in trans position, bridging) and one nitrosyl group, and pentacoordinate copper(II) with N-(2-aminoethyl)propane-1,3-diamine and two sites occupied by bridging cyanide ligands. Magnetic investigation revealed a very weak antiferromagnetic interaction between the copper atoms (superexchange interaction parameter J = -1.7(1) cm-1; H = -JSiSi+1) within the chain through the diamagnetic [Fe(CN)5NO]2- ions.
Synthesis and Cytostatic Activity of N-[2-(Phosphonomethoxy)alkyl] Derivatives of N6-Substituted Adenines, 2,6-Diaminopurines and Related Compounds
Authors: Holý Antonín , Votruba Ivan , Tloušťová Eva , Masojídková Milena
Published: July 2002

N6-Substituted adenine and 2,6-diaminopurine derivatives of 9-[2-(phosphonomethoxy)- ethyl] (PME), 9-[(R)-2-(phosphonomethoxy)propyl] [(R)-PMP] and enantiomeric (S)-PMP series were synthesized by reactions of primary or secondary amines with 6-chloro-9-{[2-(diisopropoxyphosphoryl)methoxy]alkyl}purines (26-28) or 2-amino-6-chloro-9-{[2-(diisopropoxy- phosphoryl)methoxy]alkyl}purines (29-31) followed by treatment of the diester intermediates32with bromo(trimethyl)silane and hydrolysis. Diesters32were also obtained by reaction ofN6-substituted purines with synthons23-25bearing diisopropoxyphosphoryl group. Alkylation of 2-amino-6-chloropurine (9) with diethyl [2-(2-chloroethoxy)ethyl]phosphonate (148) gave the diester149which was analogously converted toN6-substituted 2,6-diamino- 9-[2-(2-phosphonoethoxy)ethyl]purines151-153. Alkylation ofN6-substituted 2,6-diaminopurines with (R)-[(trityloxy)methyl]oxirane (155) followed by reaction of thus-obtained intermediates156with dimethylformamide dimethylacetal and condensation with diisopropyl [(tosyloxy)methyl]phosphonate (158) followed by deprotection of the intermediates159gaveN6-substituted 2,6-diamino-9-[(S)-3-hydroxy-2-(phosphonomethoxy)propyl]purines160-163. The highest cytostatic activityin vitrowas exhibited by the followingN6-derivatives of 2,6-diamino-9-[2-(phosphonomethoxy)ethyl]purine (PMEDAP): 2,2,2-trifluoroethyl (53), allyl (54), [(2-dimethylamino)ethyl] (68), cyclopropyl (75) and dimethyl (91). In CCRF-CEM cells, the cyclopropyl derivative75is deaminated to the guanine derivative PMEG (3) which is then converted to its diphosphate.
Correlates of prepubertal bone mineral density in cystic fibrosis
Authors: Haslam R H M , Borovnicar D J , Stroud D B , Strauss B J G , Bines J E
Published: July 2002

AIM

To examine early factors in bone mineral accretion in cystic fibrosis (CF).

METHODS

In 22 prepubertal children with CF and mild lung disease, the relation between total body bone mineral density (BMD) and measures of body composition, biochemistry, lung function, and physical activity was studied.

RESULTS

There was a non-significant mild reduction in mean total body BMD. No relation was found between BMD and anthropometric indices, fat free soft tissue, degree of lung disease, degree of fat malabsorption, dietary energy intake, or level of physical activity. Significant impairments in physical growth were apparent in this population and were found to correlate with degree of lung disease.

CONCLUSION

A CF specific factor appears unlikely to be associated with the osteopenia commonly found in CF. Careful attention to general aspects of lifestyle and nutrition is recommended to maximise bone mineral accretion in this population.
Escin/diethylammonium salicylate/heparin combination gels for the topical treatment of acute impact injuries: a randomised, double blind, placebo controlled, multicentre study
Authors: Wetzel D , Menke W , Dieter R , Smasal V , Giannetti B , Bulitta M
Published: July 2002

Objectives:To investigate the clinical efficacy and safety of escin-containing gels in the topical treatment of blunt impact injuries.

Methods:Competitors in soccer, handball, or karate competitions were enrolled within two hours of sustaining a strain, sprain, or contusion and treated three times with the trial gel within a period of eight hours. Patients were randomised to three parallel groups consisting of two active treatment gels, containing escin (1% or 2%), 5% diethylammonium salicylate, and 5000 IU heparin, or placebo gel. Tenderness produced by pressure was measured at 0 (baseline), 1, 2, 3, 4, 6, and 24 hours after enrolment (within two hours of the injury). Tenderness was defined as the amount of pressure (measured by a calibrated caliper at the centre of the injury) that first produced a pain reaction as reported by the patient.

Results:A total of 158 patients were enrolled; 156 were evaluated in the intention to treat analysis. The primary efficacy variable was the area under the curve for tenderness over a six hour period. The gel preparations containing 1% and 2% escin were significantly more effective (a priori ordered hypotheses testing controlling the multiple α = 5% significance level) than placebo (p1= 0.0001 and p2= 0.0002 respectively). The treatment effects were 5.7 kp h/cm2(95% confidence interval (CI) 2.9 to 8.5) and 5.9 kilopond (kp) h/cm2(95% CI 2.9 to 8.8) between 1% escin and placebo and between 2% escin and placebo respectively. These results were supported by secondary efficacy variables. The time to reach the baseline contralateral tenderness value (resolution of pain) at the injured site was shorter in the treatment groups than in the placebo group (p<0.0001). Both active gel preparations produced more rapid pain relief than the placebo gel. No relevant differences were detected between the two active gels. The safety and tolerability of the escin-containing gels were excellent.

Conclusions:Escin/diethylammonium salicylate/heparin combination gel preparations are effective and safe for the treatment of blunt impact injuries.
Public deliberation and private choice in genetics and reproduction
Authors: Parker Michael
Published: July 2002

The development of human genetics raises a wide range of important ethical questions for us all. The interpersonal dimension of genetic information in particular means that genetics also poses important challenges to the idea of patient-centredness and autonomy in medicine. How ought practical ethical decisions about the new genetics be made given that we appear, moreover, no longer to be able to appeal to unquestioned traditions and widely shared communitarian values? This paper argues that any coherent ethical approach to these questions must be able both to uphold the moral status of the individual and at the same time recognise the communitarian, interpersonal dimensions both of the world in which we live and of personal autonomy itself. The paper then goes on to propose an approach to the resolution of the ethical questions raised by the use of the new genetics in reproductive choice through the development of a coherent and principled process of public reason and justification oriented towards the support and development of personal autonomy.
Who should know about our genetic makeup and why?
Authors: Takala Tuija , Gylling Heta Aleksandra
Published: July 2002

Recent developments in biology have made it possible to acquire more and more precise information concerning our genetic makeup. Although the most far-reaching effects of these developments will probably be felt only after the Human Genome Project has been completed in a few years' time, scientists can even today identify a number of genetic disorders which may cause illness and disease in their carriers. The improved knowledge regarding the human genome will, it is predicted, in the near future make diagnoses more accurate and treatments more effective, and thereby considerably reduce and prevent unnecessary suffering. On the other hand, however, the knowledge can also be, depending on the case, futile, distressing or plainly harmful. This is why we propose to answer in this paper the dual question: who should know about our genetic makeup and why? Through an analysis of prudential, moral and legal grounds for acquiring the information, we conclude that, at least on the levels of law and social policy, practically nobody is either duty-bound to receive or entitled to have that knowledge.
Working with mentally ill homeless persons: should we respect their quest for anonymity?
Authors: Melamed Yuval , Fromer Dafna , Kemelman Ziona , Barak Yoram
Published: July 2002

In recent years, the homeless population has received much attention as authorities attempt to comprehend this phenomenon and offer solutions. When striving to establish a relationship with the homeless person, many problems arise. We encounter this dilemma when respecting the right of the mentally ill to dwell neglected in the streets and simultaneously observe their inability to comprehend provisions such as housing, shelter, medical and mental care which contribute to their human dignity. The polarities of autonomy versus involuntary treatment are highlighted when treating the homeless population.
Like marriage, without the romance
Authors: Portmann John
Published: July 2002

Physicians and philosophers have contributed to the field of medical ethics several different paradigms for the physician-patient relationship. Here I suggest another: marriage. Patients usually enter into relationships as we enter marriage: we allow our high hopes to obscure the possibility of deep disappointment. The argument of the essay encourages renewed focus on the contractual element of physician-patient relationships.
A double dose of double effect
Authors: Kendall C E
Published: July 2002

This paper presents a clinically orientated illustration of the doctrine of double effect. The case of an elderly gentleman with advanced cancer is discussed, with particular emphasis on two dilemmas encountered during the terminal phase of his illness. The author describes how the doctrine of double effect was applied to help the team make some complex management decisions.
Medical confidentiality and the protection of Jehovah's Witnesses' autonomous refusal of blood
Authors: Muramoto Osamu
Published: July 2002

Mr Ridley of the Watch Tower Society (WTS), the controlling religious organisation of Jehovah's Witnesses (JWs), mischaracterises the issue of freedom and confidentiality in JWs' refusal of blood by confusing inconsistent organisational policies with actual Biblical proscriptions. Besides exaggeration and distortion of my writings, Ridley failed to present substantive evidence to support his assertion that no pressure exists to conform to organisational policy nor systematic monitoring which compromises medical confidentiality. In this refutation, I present proof from the WTS's literature, supported by personal testimonies of JWs, that the WTS enforces its policy of blood refusal by coercive pressure to conform and through systematic violation of medical confidentiality. Ridley's lack of candour in dealing with the plea of dissident JWs for freedom to make personal and conscientious decisions regarding blood indicates that a serious breach of ethics in the medical care of JWs continues. The medical community should be seriously concerned.
Mortality and cancer incidence among Swedish lumberjacks exposed to phenoxy herbicides: Table 1
Authors: Thörn Åke , Gustavsson Per , Sadigh Jonas , Westerlund-Hännestrand Brita , Hogstedt Christer
Published: July 2002

OBJECTIVES

To determine mortality and cancer incidence relative to exposure to phenoxy herbicides.

METHODS

A cohort of Swedish lumberjacks of which 261 were exposed to phenoxy herbicides, and 250 were unexposed, was followed up for mortality from 1954 to 1994, and for cancer incidence from 1958 to 1992. The number of days of exposure to phenoxy herbicides was determined from pay slips. With the county population as a reference, standardised mortality ratios and cancer incidence ratios (SMR and SIR) were calculated.

RESULTS

Mortality and cancer incidence were low with two exceptions; a small but highly exposed group of foremen showed an increased cancer incidence (SIR 274, 95% confidence interval (95% CI) 100 to 596), and over all mortality (SMR 141, 95% CI 68 to 260). Of three cases of non-Hodgkin's lymphoma, two were found among the most exposed workers.

CONCLUSIONS

The results provide some support to claims of previous studies that exposure to phenoxy herbicides might be related to non-Hodgkin's lymphoma and to an increased overall cancer risk.
Associations between ambient ozone, hydrocarbons, and childhood wheezy episodes: a prospective observational study in south east London
Authors: Buchdahl Roger , Willems Charlotte Daman , Vander Margaret , Babiker Abdel
Published: July 2002

OBJECTIVES

To explore the hypothesis that hydrocarbon species and other air pollutants which accumulate at low and high concentrations of ozone are more directly associated with childhood wheezy episodes than ozone.

METHODS

Prospective observational study over 1 year set in the Lewisham district of south east London. The daily attendance rate of children with acute wheeze at the accident and emergency department of Lewisham Hospital was related to local measurements of ozone, hydrocarbon species, nitrogen dioxide (NO2), sulphur dioxide (SO2) and small particulate matter with diameter <10μm (PM10).

RESULTS

An inverse relation was found between the air pollutants and ozone. After seasonal and meteorological adjustment a non-linear U shaped trend was found between incidence of wheeze and ozone. The trend was significant in children <2 years of age but not in older children. In the younger age group, after adjustment for season, temperature, wind speed, and respiratory infection, the incidence relative to that at the mean daily ozone concentration of 32.7 μg/m3, was estimated to increase by 65% (95% confidence interval (95% CI) 22% to 122%) at an ozone concentration of 5 μg/m3(1.5 SDs below the mean) and by 63% (95%CI −6% to 184%) at 80 μg/m3(2.5 SDs above the mean). For several hydrocarbons there were significant positive linear relations found, again in children <2 years of age but not older children. For benzene, the incidence increased by 8% (95% CI 2 to 13%) per SD (SD 2.8 μg/m3) increase in benzene concentration. A same day association between incidence and ozone was found to be the most significant but for other pollutants a lag of 2 days gave the most significant associations. No significant association was found for the non-hydrocarbon pollutants including SO2, NO2, and PM10.

CONCLUSIONS

A U shaped relation was found between ozone and the incidence of wheezy episodes in young children. Certain hydrocarbon pollutants accumulate in the atmosphere when ozone concentrations are low, and are associated with childhood wheezy episodes. However, the U shaped association of ozone on incidence cannot be explained by these other pollutants. The finding supports an earlier finding that incidences of wheeze are at a minimum when ozone concentrations are 30–40 μg/m3.
Effect of exposure to lead on postural control in workers
Authors: Ratzon N , Froom P , Leikin E , Kristal-Boneh E , Ribak J
Published: July 2002

OBJECTIVES

To examine the effect of lead on postural control of workers who have been exposed to lead.

METHODS

63 Male, lead battery workers mean (SD) age 41.0 (7.4) were compared with 48 age matched male controls after excluding those with acute or chronic diseases. Exposed workers had mean (SD) past blood lead concentrations of 37.5 (9.2) μg/dl and 11.2 (5.7) years of employment. Postural control was measured with a computerised postural sway measurement system which measured both sway and total movements.

RESULTS

Workers standing straight with eyes open on the bare plates had sway and total movements which were not notably different from controls. On the other hand increased movements were needed in the exposed workers to maintain stability (the general stability quotient 18.2 (5.4)v15.4 (4.4) in controls, p<0.01) when standing directly on the footplates with closed eyes,, and with the head tilted (15.0 (3.8)v11.5 (3.0) in controls, p<0.001). Exposed workers also had a trend for less ability to synchronise anterior posterior and lateral sway in the stress positions (0.0625) than had non-exposed workers . Significant but low correlations were found between the estimate of the chronic internal dose of lead and three of 10 of the postural control measurements, and present lead blood concentrations and only one of the 10 measurements and (rvalues ranged from 0.21 to 0.31, p⩽0.03).

CONCLUSIONS

These findings suggest that lead affects postural control in asymptomatic workers. Further studies are warranted to find whether workers with decreased postural control are at increased risk of accidents and the relation, if any, of these measurements with subsequent morbidity.
Prevalence and pattern of occupational exposure to hand transmitted vibration in Great Britain: findings from a national survey
Authors: Palmer Keith T , Griffin Michael J , Bendall Holly , Pannett Brian , Coggon David
Published: July 2002

OBJECTIVES

To estimate the number of workers in Great Britain with significant occupational exposure to hand transmitted vibration (HTV). Also, to identify the occupations and industries where such exposures arise, and the main sources of exposure.

METHODS

A questionnaire was posted to 22 194 men and women aged 16–64, comprising 21 201 subjects selected at random from the age-sex registers of 34 general practices in England, Scotland, and Wales, and a further 993 subjects selected at random from the central pay registers of the three armed services. Among other things, the questionnaire asked about exposure to sources of HTV in current and earlier employment. Responses were assessed by occupation and industry, and prevalence estimates for the country as a whole were derived from census information on occupational and industrial populations nationally. Estimates were also made in exposed workers of the average daily dose of vibration (A(8) root mean squared (rms) for the past week, based on their reported sources and durations of exposure.

RESULTS

Usable questionnaires were returned by 12 907 subjects (overall response rate 58%). From these it was estimated that some 4.2 million men and 667 000 women in Great Britain are exposed to HTV at work in a 1 week period, and that personal daily exposures to vibration exceed a suggested action level equivalent to 2.8 ms-2for 8 hours (A(8) >2.8 ms-2rms) in at least 1.2 million men and 44 000 women. High estimated doses (A(8) >5 ms-2rms) arose most often in bricklayers and masons, gardeners and groundsmen, carpenters and joiners, electricians and electrical maintenance fitters, and builders and building contractors. The industries where high A(8) values most often arose were construction, motor vehicle repair and maintenance, manufacture of basic metals, and agriculture. The most common sources of exposure were hammer drills, hand held portable grinders, and jigsaws.

CONCLUSIONS

Exposure to HTV is surprisingly prevalent, and preventive measures and health surveillance may be warranted for many men in Britain. Control strategies should focus on prevention at source, with priority accorded to the common sources of exposure and the occupations in which significant exposures tend to arise. Many vibratory tools that are common in Britain have been overlooked in previous surveys, highlighting an important focus for future research.
Cohort mortality and cancer incidence survey of recent entrants (1982–91) to the United Kingdom rubber industry: preliminary findings: Table 1
Authors: Straughan J K , Sorahan T
Published: July 2002

OBJECTIVES

To monitor the occurrence of stomach and lung cancer in a newly defined cohort of United Kingdom rubber workers and to report findings for other cancers in an early period of follow up.

METHODS

A prospective cohort of 9031 male and female workers from 42 United Kingdom rubber factories has been enumerated. All employees had a minimum of 12 months employment and were first employed at one of the participating factories in the period 1982–91. Mortality data were available for the period 1983–98 and cancer registration data for the period 1983–94. The mortality and cancer incidence experienced by the cohort were compared with expected values based on national rates defined by period, age, and sex.

RESULTS

Mortality from lung cancer was close to expectation (men: observed (obs) 11, expected (exp) 12.70, standardised mortality ratio (SMR) 87, 95% confidence interval (95% CI) 43 to 155; women: obs 0, exp 1.34, SMR 0, 95% CI 0 to 275). Mortality from stomach cancer was unexceptional (men: obs 1, exp 2.69, SMR 37, 95% CI 1 to 207; women: obs 0, exp 0.24, SMR 0, 95% CI 0 to 1537). Many statistical comparisons were made both for mortality data and for cancer registration data; only one difference between observed and expected numbers was significant (mortality from cancer of the testis: obs 3 exp 0.51, SMR 589, 95% CI 122 to 1722). Corresponding findings for incident cancers of the testis were unexceptional (obs 5, exp 5.13, standardised registration ratio (SRR) 97, 95% CI 32 to 227).

CONCLUSION

The findings should be treated with caution as they relate to an early period of follow up. Nevertheless, they hold out the prospect that the increased SMRs for stomach and lung cancers reported for historical cohorts of United Kingdom rubber workers may not be apparent in more recent cohorts.
Evaluation of a modified German version of the Q16 questionnaire for neurotoxic symptoms in workers exposed to solvents
Authors: Ihrig A , Triebig G , Dietz M C
Published: July 2002

OBJECTIVES

To assess sensitivity and specificity of a questionnaire designed to detect neurotoxic symptoms in workers exposed to solvents and in patients with a psycho-organic syndrome.

METHODS

The Swedish Q16 is a self administered questionnaire for neurotoxic symptoms. The modified German version consists of 18 questions. The results were analysed from 1166 questionnaires which were completed by adults belonging to the following groups; 483 workers with occupational exposure to solvents and 193 non-exposed controls, 25 patients with a psycho-organic syndrome, 25 sex and age matched patients with a lung disease, and a sample of 440 people from the general population.

RESULTS

The German Q18 was easy to handle and quick to perform. Workers exposed to solvents reported significantly more complaints than controls (2.9v2.5). All patients with a psycho-organic syndrome had five or more complaints. This was true for only 32% of patients with lung disease. These comparisons showed that chronic exposure to solvents was associated with subjective complaints related particularly to cognitive functions. In the sample of the general population, age, education level, smoking habits, and time of performance showed no significant influence on the Q18 result. Women had significantly more complaints than men (3.2v2.3). People who reported drinking alcohol occasionally or moderately had significantly fewer complaints than teetotalers.

CONCLUSIONS

The German Q18 has an acceptable sensitivity and reliability, a reasonable specificity, and a good practicability. It is a useful instrument for screening workers exposed to solvents. A cut off point of 5 for men is recommended, and a cut off point of 6 for women is proposed.
Comparing performance on a simulated 12 hour shift rotation in young and older subjects
Authors: Reid K , Dawson D
Published: July 2002

OBJECTIVES

To simulate a 12 hour shift rotation and measure the difference in performance if any, between older and younger subjects. Significant reductions in neurobehavioural performance during shift work and particularly night work have long been recognised. There are conflicting reports of the effects of 12 hour shifts on performance, alertness, and safety. Furthermore, research suggests that older shift workers have more sleep disruption and maladaption to shift work. When this is combined with longer hours at work there may be considerable reductions in performance for older compared with younger workers.

METHODS

Thirty two subjects were allocated to groups according to age. Group one had 16 subjects with a mean (SD) age of 21.2 (2.7) years, and group two had 16 subjects with a mean (SD) age of 43.9 (6.8) years. Subjects came to the laboratory for six consecutive days and completed a simulated 12 hour shift rotation consisting of two 12 hour day shifts (0700–1900), followed by two 12 hour night shifts (1900–0700). During the work period subjects completed a computer administered neurobehavioural performance task every hour.

RESULTS

Performance for the older subjects was consistently lower than for the younger subjects. There was a significant difference in performance across the shift between older and younger subjects. There was a significant change in performance across the shifts in the older subjects, such that performance significantly increased across the day shifts and decreased across the night shifts. By contrast, the younger subjects were able to maintain performance across both day shifts and the second night shift.

CONCLUSIONS

There are significant differences in performance of older and younger subjects during a simulated 12 hour shift rotation. Future studies both in the field and the laboratory would be useful in determining whether this is typical and if there are any important consequences for the older worker on 12 hour shifts.
Urinary 1-hydroxypyrene in coke oven workers relative to exposure, alcohol consumption, and metabolic enzymes
Authors: Zhang J , Ichiba M , Hara K , Zhang S , Hanaoka T , Pan G , Yamano Y , Takahashi K , Tomokuni K
Published: July 2002

OBJECTIVES

To investigate the influence of personal lifestyle—such as smoking and alcohol consumption—on urinary 1-hydroxypyrene (1-OHP) concentrations in coke oven workers exposed to polycyclic aromatic hydrocarbons (PAHs) and to evaluate the association of 1-OHP concentrations with the genetic polymorphism of several metabolic enzymes including cytochromeP-450 (CYP) 1A1 and glutathione S-tranferases (GSTs).

METHODS

The study population contained 162 coke oven workers and 58 controls employed at the largest iron and steel factory in China. Personal data were collected at the interview. 1-OHP in urine was measured with high performance liquid chromatography with fluorescence detection. Genetic polymorphisms were identified by the polymerase chain reaction (PCR) method.

RESULTS

A positive association between excretion of urinary 1-OHP and the levels of exposure to PAHs was confirmed. Those people who consumed ⩾50 g/day ethanol had significantly higher 1-OHP excretion than did other coke oven workers (p<0.01). No significant difference in urinary 1-OHP was found between smokers and non-smokers, in both controls and exposed subjects. The variant homozygotes at exon 7 of the CYP1A1 gene had significantly higher urinary 1-OHP concentrations than other CYP1A1 genotypes among the exposed workers (p=0.03). There was less association between the concentrations of 1-OHP and the GSTM1, GSTP1, or GSTT1 polymorphism.

CONCLUSIONS

The present study confirmed that urinary 1-OHP is a good biomarker for exposure to PAHs. Alcohol consumption affected urinary 1-OHP excretion. The variant genotypes of the CYP1A1 gene may result in the enhancement of PAH metabolites. It is helpful to understand the role of individual susceptibility on metabolism of carcinogens. These findings suggest that the modulating effect of individual lifestyle factors or genetic nature should be considered in future studies on occupational exposure to PAHs and in evaluating the health risk from harmful chemicals.
Stimulation of IL-8 release from epithelial cells by gas cooker PM10: a pilot study
Authors: Dick C A J , Dennekamp M , Howarth S , Cherrie J W , Seaton A , Donaldson K , Stone V
Published: July 2002

OBJECTIVE

To measure the effect of matter collected by a method that has a 50% efficiency for particles with an aerodynamic diameter of 10 μm (PM10), generated by gas and electric cooking, on A549 epithelial cells with and without nitrogen dioxide (NO2).

METHOD

Multiple indoor PM10samples were collected on Teflon filters during the use of gas or electric cookers. Interleukin-8 (IL-8) concentrations were measured with a sandwich enzyme linked immunosorbent assay (ELISA) system.

RESULTS

Treatment of A549 cells with PM10generated from gas cooking resulted in increased concentrations of IL-8 compared with untreated cells; particles from the electric cooker had no effect. NO2did not alter the concentration of IL-8.

CONCLUSION

PM10generated by gas cooking has the potential to cause proinflammatory effects in lung cells. This may have implications for susceptible people.
Small area estimation of incidence of cancer around a known source of exposure with fine resolution data
Authors: Kokki E , Ranta J , Penttinen A , Pukkala E , Pekkanen J
Published: July 2002

OBJECTIVES

To describe the small area system developed in Finland. To illustrate the use of the system with analyses of incidence of lung cancer around an asbestos mine. To compare the performance of different spatial statistical models when applied to sparse data.

METHODS

In the small area system, cancer and population data are available by sex, age, and socioeconomic status in adjacent “pixels”, squares of size 0.5 km × 0.5 km. The study area was partitioned into sub-areas based on estimated exposure. The original data at the pixel level were used in a spatial random field model. For comparison, standardised incidence ratios were estimated, and full bayesian and empirical bayesian models were fitted to aggregated data. Incidence of lung cancer around a former asbestos mine was used as an illustration.

RESULTS

The spatial random field model, which has been used in former small area studies, did not converge with present fine resolution data. The number of neighbouring pixels used in smoothing had to be enlarged, and informative distributions for hyperparameters were used to stabilise the unobserved random field. The ordered spatial random field model gave lower estimates than the Poisson model. When one of the three effects of area were fixed, the model gave similar estimates with a narrower interval than the Poisson model.

CONCLUSIONS

The use of fine resolution data and socioeconomic status as a means of controlling for confounding related to lifestyle is useful when estimating risk of cancer around point sources. However, better statistical methods are needed for spatial modelling of fine resolution data.
Routine diagnostic procedures for chronic encephalopathy induced by solvents: survey of experts
Authors: van der Hoek J A F , Verberk M M , van der Laan G , Hageman G
Published: July 2002

OBJECTIVES

To study the routine diagnostic procedures used in different countries for chronic toxic encephalopathy (CTE) induced by solvents.

METHODS

By means of a postal questionnaire selected international experts were asked about the methods they use to diagnose patients suspected of having CTE induced by solvents, the number of patients, entrance criteria, and the results of these diagnostic procedures.

RESULTS

18 Experts working in 18 diagnostic centres responded. Most of them agreed that a diagnostic procedure for CTE induced by solvents should contain an interview and neurological, physical, and neuropsychological examinations. However, the tests used were very different, as were the classifications for CTE. Depending on the institute, a diagnosis of CTE was made in 6%–70% of the referred patients. The proportion of patients with CTE stage I ranged from 0% to 33%, stage II from 5% to 100%, and stage III from 0% to 95%.

CONCLUSION

The intentions of the two 1985 conferences that aimed at clarity and uniformity of diagnosis of CTE induced by solvents are far from reached. It is possible, now the conditions are more favourable, to aim at this important goal and recommend some refinement of the then proposed criteria.