bluuebunny/crossref_metadata_2025 huggingface dataset:
Construction of the Side-Chain in 14β-Androst-5-ene Derivatives. Preparation of 14β-Pregnenolone
Authors: Černý Ivan , Buděšínský Miloš , Drašar Pavel , Pouzar Vladimír
Published: July 2002

Stepwise side-chain construction schemes leading to pregnane derivatives were tested in the 14β-androst-5-ene series. 6β-Methoxy-3α,5-cyclo-5α,14β-androstan-17-one (I) gave after methylenation and hydroboration the 17α-hydroxymethyl derivative III. Subsequent oxidation to the aldehyde VI, Grignard reaction with methylmagnesium iodide, and reoxidation led to the ketone VII and to the isomeric 17β-derivative VIII as a minor product. Final i-steroid cleavage of VII furnished the known 14β,17α-pregnenolone IX; the minor product VIII gave the 17β-isomer X. Alternatively, the ketone X was prepared from 6β-methoxy-3α,5-cyclo-5α,14β-androstan-17α-ol p-toluenesulfonate (XI) by cyanide substitution, diisobutylaluminum hydride reduction to the aldehyde XIV, and further as described for IX. The mass and NMR spectra of the four pregnenolone derivatives IX, X, XVIII, and XIX, isomeric in positions 14 and 17, were studied.
17-(O-(2-Carboxyethyl)oxime) Derivatives of Androstanes of 3-Hydroxy-5α-, -5β-, -5-ene and 3-Oxo-4-ene Series
Authors: Pouzar Vladimír , Černý Ivan
Published: July 2002

Androstane 17-(O-(2-carboxyethyl)oxime) derivatives were prepared either by the reaction of 17-keto derivatives with corresponding substituted hydroxylamine or by the addition of 17-oximino derivatives to the alkyl acrylate and subsequent hydrolysis. Oxidation of the hydroxy group in position 3 in derivatives of this type was performed either by the Oppenauer reaction, transforming 5-ene derivatives into 3-oxo-4-enes, or with Jones reagent in the case of saturated 5α- or 5β-derivatives. Configuration 17E in the whole series of oximes was confirmed by the 1H and 13C NMR spectroscopy.
Synthesis of Pyrazole Analogs from Argentatin B
Authors: Martínez Roberto , Limón Elda , Arellano María del R. , Martínez Mariano , Brito Marco
Published: July 2002

The pyrazole derivatives 3'-(2-R-phenyl)[3,2-c]pyrazole-16,24-epoxy-25-hydroxy-9 ,19-cyclostane Va - Vf have been prepared in a three step reaction from argentatin B. The structure of all the compounds synthesized was corroborated by 1H and 13C NMR, IR and mass spectroscopy.
Synthesis of Substituted Furo[2',3':4,5]pyrrolo[1,2-d][1,2,4]triazolo[3,4-f][1,2,4]triazines
Authors: Bobošík Vladimír , Krutošíková Alžbeta , Dandárová Miloslava
Published: July 2002

The title compounds were prepareed by reaction of 1,2-dihydrofuro[2',3':4,5]pyrolo[1,2-d][1,2,4]-1-hydrazones by cyclization with triethyl orthoformiate or triethyl orthoacetate. All compounds were characterized by elemental analyses, UV and 1H NMR spectra.
Chemometric Analysis of Substituent Effects. VII. Inductive Effect as a Basic Substituent Effect. Isoeffect Substituent Constant
Authors: Pytela Oldřich , Halama Aleš
Published: July 2002

The paper deals with chemometric analysis of the inductive effect. The notion of inductive effect is discussed, and unambiguous definitions are given for the notions of triad: reaction centre-basic skeleton-substituent, and the therewith connected definitions of inductive effect. For a quantitative description of inductive effect 7 types of chemical models were selected including noncyclic compounds, cyclic, and bicyclic compounds, derivatives of quinuclidine, 3-substituted benzoic acids, sulfonamides and pyridines. Altogether 139 sets of experimental data from literature have been used including altogether 1 294 points (9.3 points per set, 5 points at least) reflecting substituent effects of 34 substituents. It has been found that for a standard model the dissociation of substituted bicycloalkanecarboxylic acids only is satisfactory, all the other models reflecting also the mesomeric effects to variable extent (up to 10%). A distinctly different substitution behaviour was observed with 19F and 13C NMR chemical shifts of 4-substituted 1-fluoro- or 1-methylbicyclo[2.2.2]octanes. The earlier suggested model of substituent effects based on different way of transmission of substituent effects (3 classes) has been used for separating the inductive and mesomeric effects: it is mathematically presented as a set of straight lines with the intersection point at the so-called isoeffect substituent constant. Using the modified method of conjugated deviations a chemometric scale has been created for the inductive effect which agrees very well with the conventional scales given in literature; the only differences were observed for F and CH=O substituents (which are overestimated and underestimated, respectively, in literature). In the context given the inductive effect appears as a fundamental quantity forming a basis for quantitative description of other effects transferred by electrons.
Synthesis of 2α,3α-Epoxy-9β-benzoyloxy-β-agarofuran and 2,3-Dehydro-4β,12-epoxy-9β-benzoyloxy-β-dihydroagarofuran
Authors: Nan Fajun , Liu Lijun , Xiong Zhaoming , Chen Yonggang , Li Tongshuang , li Yulin
Published: July 2002

The first stereoselective synthesis of 2α,3α-epoxy-9β-benzoyloxy-β-agarofuran (3) and 2,3-dehydro-4β,12-epoxy-9β-benzoyloxy-β-dihydroagarofuran (4) from (-)-carvone in 13 steps, respectively, has been described. In addition, the synthesis of 2,3-dehydro-4β,9β-dihydroxy-β-dihydroagarofuran (13) has also been reported. By the reduction of 4 to give 13, the 4β,12-epoxy configuration of 4 was established.
Metallomicellar Hydrolytic Catalysts Containing Ligand Surfactants Derived from Alkyl Pyridin-2-yl Ketoxime
Authors: Cibulka Radek , Dvořák David , Hampl František , Liška František
Published: July 2002

N-Hexyl- (2a), N-octyl- (2b), N-decyl- (2c) and N-dodecyl-N-[2-(hydroxyimino)-2-(pyridin-2-yl)ethyl]dimethylammonium (2d) nitrates were synthesized as water-soluble cationic ligand surfactants. Three types of micellar catalytic systems employing salts 2 were prepared: homomicellar water solutions of salts 2, comicellar solutions of salts 2 with an inert cationic tenside hexadecyltrimethylammonium bromide (CTAB) and comicellar systems consisting of complexes of ligand surfactants 2 with transition metal ions (Co(II), Ni(II), Cu(II) and Zn(II)) and CTAB. Hydrolytic efficiency of all micellar and metallomicellar systems was tested by measuring the kinetics of the model substrate cleavage under pseudo-first-order reaction conditions. Of the above-mentioned catalysts, comicellar systems of salts 2 comicellized with CTAB were most efficient. In all cases, with the exception of Zn(II), coordination of a metal ion decreased the hydrolytic efficiency of salts 2.
Acetal Formation is Responsible for the Non-Closed Form of Monensin A in Methanolic Solution
Authors: Sedmera Petr , Pospíšil Stanislav
Published: July 2002

NMR evidence shows that so-called non-closed form of monensin A free acid reported to exist in methanol is in fact due to acetal formation at C-25. The 25-alkoxy derivatives retain this conformation even in non-polar media.
Oxidation of the [nido-6,9-C2B8H10]2- Anion - An Alternative Source of the 1,6- and 1,10-Dicarba-closo-decaboranes(10)
Authors: Štíbr Bohumil , Janoušek Zbyněk , Trammell Matthew , Grüner Bohumír , Plzák Zbyněk
Published: July 2002

The oxidation of the [nido-6,9-C2B8H10]2- (1) dianion with CuCl2, is supposed to proceed via an unstable closo-2,6-C2B8H10 (2) intermediate, which is then rearranged into closo-1,6-C2B8H10 (3) (yields 30-35%). The synthesis is accompanied by the formation of the isomeric closo-dicarbaboranes 1,10-C2B8H10 (4) and 1,2-C2B8H10 (5) and the whole procedure can be modified to isolate only isomer 4 (yield 35%). Side products from the synthesis consist of a complex and so far unseparable mixture, in which arachno-4,6-C2B7H13, chloro derivatives closo-C2B8H9Cl, and trimeric compounds of a closo-(C2B8H9)2-C2B8H8 formulation were detected by GLC/MS techniques. These findings point to the involvement of a radical-chain mechanism in the reaction.
Gravity Effect on the Formation of Periodic Precipitation Patterns
Authors: Holba Vladislav , Fusek Frederik
Published: July 2002

The effect of gravity on the formation of Liesegang patterns of Ag2Cr2O7in gelatin and that of PbI2in agar was investigated. Spatial arrangement of Liesegang bands was measured in the parallel and antiparallel orientation to the gravitational field in a single sample with all other parameters kept fixed. The experimental results are discussed in terms of the prenucleation theory of periodic precipitation.
Synthesis and Acid-Catalyzed Hydrolysis of Some 3-(4-Methoxyphenyl)propyl Glucuronates
Authors: Poláková Monika , Joniak Dušan , Ďuriš Miloslav
Published: July 2002

3-(4-Methoxyphenyl)propyl D-glucuronate, 3-(4-methoxyphenyl)propyl methyl 4-O-methyl-α-Dglucopyranosiduronate, 3-(4-methoxyphenyl)propyl 1,2,3,4-tetra-O-acetyl-α-D-glucopyranuronate and 3-(4-methoxyphenyl)propyl 1,2-(S):3,5-di-O-benzylidene-α-D-glucofuranuronate were prepared as a model substances for the ester lignin-saccharide bonds. Rates of acid-catalyzed hydrolysis of the prepared compounds in 1 M HCl in acetonitrile-water 3 : 1 at 20 °C have been measured by LC-DAD analysis and it showed the low stability of the ester bonds towards acid hydrolysis.
Dichotomy in the Ring Opening Reaction of 5-[(2-Furyl)methylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione with Cyclic Secondary Amines
Authors: Šafář Peter , Považanec František , Prónayová Naďa , Baran Peter , Kickelbick Guido , Kožíšek Jozef , Breza Martin
Published: July 2002

5-[(2-Furyl)methylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione (1a) treated with equimolar amount of pyrrolidine or hexahydroazepine afforded 5-(pyrrolidine)- (2a) or 5-[(hexahydro- azepine-1-yl)-2-hydroxypenta-2,4-dien-1-ylidene]-2,2-dimethyl-1,3-dioxane-4,6-dione (2d). Their treatment with hydrobromic acid led to cyclization and formation of stable 5-cyclopentenyl-4H-1,3-dioxine hydrobromides (3a, 3d). Under the same conditions 1a treated with morpholine or piperidine yielded a mixture of 2b, 3b and 2c, 3c, respectively. The corresponding 3-substituted furans 1b-1e gave only substituted 5-cyclopentenyl-4H-1,3-dioxines (3e-3i). The use of an excess amine in reaction with 1a yielded unexpectedly 5-(3,5-dihetaryl-cyclopent-2-en-1-ylidene)-2,2-dimethyl-1,3-dioxane-4,6-diones (9a-9c) and 5-[5-hexahydroazepin-1-ium-1-ylidene-2-(hexahydroazepin-1-yl)cyclopent-1-en-1-yl]-2,2-dimethyl-4-oxo-4H-1,3-dioxin-6-olates (10).
Coupling of Electron Transfer and Bond Dissociation Processes in Dinuclear Complexes with Rhodium and Iridium Reaction Centres Bridged by 2,2'-Bipyrimidine
Authors: Kaim Wolfgang , Reinhardt Ralf , Greulich Stefan , Sieger Monika , Klein Axel , Fiedler Jan
Published: July 2002

The complexes [{MCl(η5-C5Me5)}2(μ-bpym)](PF6)2, bpym = 2,2'-bipyrimidine and M = Rh or Ir, were obtained as isomerically pure species (M = Ir) or as mixtures of cis/trans isomers (M = Rh). Even though these compounds undergo partial dissociation into the mononuclear bpym- and solvento-complexes in DMF or acetonitrile, cyclic voltammetry and, in part, spectroscopy (NMR, EPR, UV-VIS) could be used to analyze their reduction with up to five electrons. In acetonitrile at room temperature, the dirhodium compound displays two sequential chloride-dissociative two-electron cathodic steps, leading to the very reactive [{Rh(η5-C5Me5)}2(μ-bpym)]. At -15 °C in DMF, the diiridium compound was found to be sufficiently inert towards dissociation; it is then reversibly reduced to an EPR-detectable radical cation [{IrCl(η5-C5Me5)}2(μ-bpym)]•+ before two separated chloride-dissociative steps occur.
Adsorptive Stripping Voltammetric Determination of Aluminium Using Arsenazo III
Authors: Komersová Alena , Bartoš Martin , Kalcher Kurt , Vytřas Karel
Published: July 2002

A new analytical method for the indirect determination of trace amounts of aluminium(III) is based on the adsorptive accumulation of an azo dye, Arsenazo III, on the hanging mercury drop electrode. In the presence of Al(III) forming complexes with the dye, its peak occurring at -330 mV decreases. Optimized experimental conditions were found as follows: supporting electrolyte, acetate or chloroacetate-acetate buffer (pH 3.6); accumulation potential, -50 mV vs SCE; accumulation time, 120 s; Arsenazo III concentration, 5 · 10-7 mol l-1; scan rate, 20 mV s-1; initial potential, -500 mV; final potential, 0 mV; FSDPV mode; pulse amplitude, 50 mV; pulse duration, 100 ms; pulse interval, 10 ms. Under these experimental conditions, the calibration dependence was linear in the concentration range 0-6 μmol l-1 with a detection limit of 3.7 · 10-8 mol l-1 (1 ppb, calculated as 3σ for n = 10). Interference of iron(III) can be suppressed by addition of L-ascorbic acid, the effect of numerous divalent metal ions is negligible. Serious interfering effects were observed for U(VI) as UO22+, both Cr(III) and Cr(VI), and F-. The method developed was verified using a certified reference material (SRM 1575 Pine Needles); no statistically significant differences between the determined and declared contents were found.
The Synthesis and Structural Characterization of a Two-Dimensional Coordination Polymer [Co(H2O)(phen)(μ4-bta)1/2]n (H4bta = Benzenetetracarboxylic Acid)
Authors: Chu De-Qing , Xu Ji-Qing , Tang Ao-Qing
Published: July 2002

Complex [Co(H2O)(phen)(μ4-bta)1/2]n was hydrothermally synthesized from sodium benzene-1,2,4,5-tetracarboxylate, 1,10-phenanthroline and CoCl2·6H2O, and structurally characterized by single-crystal X-ray crystallography, showing that it possesses a novel two-dimensional polymeric structure.
Intramolecular Diels-Alder Cycloadditions of cis-Cyclohexadienediols Derived Enzymatically from (2-Azidoethyl)benzene. Construction of Highly Functionalized Bridged Isoquinoline Synthons
Authors: Zezula Josef , Hudlický Tomáš , Ghiviriga Ion
Published: July 2002

(3aR,7aS)-4-(2-Azidoethyl)-2,2-dimethyl-3a,7a-dihydrobenzo[1,3]dioxole (22) was converted in two steps to trienes23and24, which upon heating underwent intramolecular Diels-Alder reactions to give mixtures of isomeric 11,11-dimethyl-5-oxo-10,12-dioxa-4-azatetracyclo[6.5.2.01,6.09,13]pentadec-14-ene-7-carboxylates25,26and27,28, respectively. These products were separated and identified. For comparison, intermolecular Diels-Alder cycloaddition of diene22with maleic anhydride was carried out. Products of this reaction, 1-(2-azidoethyl)-4,4-dimethyl-3,5,10-trioxatetracyclo[5.5.2.02,6.08,12]tetradec-13-ene-9,11-diones (29and30) were converted to methyl ester analogues of31and32in a two-step sequence. The stereochemical outcome of these cycloadditions is discussed as well as their possible utilization in organic synthesis, especially in total synthesis of some alkaloids.
Methods of appointment and qualifications of club doctors and physiotherapists in English professional football: some problems and issues
Authors: Waddington I , Roderick M , Naik R
Published: July 2002

Objective—To examine the methods of appointment, experience, and qualifications of club doctors and physiotherapists in professional football.

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

Results—In almost all clubs, methods of appointment of doctors are informal and reflect poor employment practice: posts are rarely advertised and many doctors are appointed on the basis of personal contacts and without interview. Few club doctors had prior experience or qualifications in sports medicine and very few have a written job description. The club doctor is often not consulted about the appointment of the physiotherapist; physiotherapists are usually appointed informally, often without interview, and often by the manager without involving anyone who is qualified in medicine or physiotherapy. Half of all clubs do not have a qualified (chartered) physiotherapist; such unqualified physiotherapists are in a weak position to resist threats to their clinical autonomy, particularly those arising from managers' attempts to influence clinical decisions.

Conclusions—Almost all aspects of the appointment of club doctors and physiotherapists need careful re-examination.
Injuries in whitewater kayaking
Authors: Fiore D C , Houston J D
Published: July 2002

Objective—To provide epidemiological data on whitewater kayaking injuries using a descriptive study.

Methods—A retrospective survey was distributed at whitewater events and club meetings, and made available and advertised on the world wide web, through postings and announcements to newsgroups, related sites, and search engines. Data on sex, age, experience, and ability were collected. Injury data collected included mechanism, activity, difficulty of rapid, and self reported severity.

Results—Of the 392 kayaking respondents included in the final analysis, 219 suffered 282 distinct injury events. The number of days spent kayaking per season was the only independent predictor of injury. The overwhelming majority of injuries occurred while the kayaker was still in the boat (87%). Striking an object was the most common mechanism of injury (44%), followed by traumatic stress and overuse (25% each). The most common types of injury were abrasion (25%), tendinitis (25%), contusion (22%), and dislocation (17%). The upper extremity, especially the shoulder, was the most commonly injured area of the body. Although half of injured kayakers sought medical care for their injury, and almost one third missed more than one month of kayaking because of the injury, almost all (96%) reported a complete or good recovery.

Conclusions—Factors relating to likelihood of injury appear to be connected with exposure, namely the number of days a year that the sport was pursued. Except for class V (extreme) kayakers, reports of injuries paralleled the number of participants. Kayakers reported injuries predominantly on rivers that they assessed to be at a level appropriate to their skills.
Are synchronised swimmers at risk of amenorrhoea?
Authors: Ramsay R , Wolman R
Published: July 2002

Objective—Synchronised swimming is a sport that shares certain characteristics with other aesthetically pleasing sports such as gymnastics and dance. The purpose of this investigation was to ascertain whether the highest ranked synchronised swimmers in the United Kingdom experience menstrual abnormalities, a common medical problem seen in these related activities.

Methods—Twenty three members of the Great Britain synchronised swimming squad completed a questionnaire on menstrual history. Body composition and Vo2maxwere measured in the laboratory during regular physiological screening.

Results—Three of the 23 subjects were oligomenorrhoeic and none were amenorrhoeic. All were postmenarchal. Mean estimated body fat percentage was 23%, and mean Vo2maxwas 47.2 ml/kg/min.

Conclusions—It appears that synchronised swimmers in the United Kingdom are relatively protected from menstrual disturbances for reasons that cannot be explained in isolation.
Human embryonic stem cells and respect for life
Authors: Meyer John R
Published: July 2002

The purpose of this essay is to stimulate academic discussion about the ethical justification of using human primordial stem cells for tissue transplantation, cell replacement, and gene therapy. There are intriguing alternatives to using embryos obtained from elective abortions and in vitro fertilisation to reconstitute damaged or dysfunctional human organs. These include the expansion and transplantation of latent adult progenitor cells.
Are medical ethicists out of touch? Practitioner attitudes in the US and UK towards decisions at the end of life
Authors: Dickenson Donna L
Published: July 2002

Objectives—To assess whether UK and US health care professionals share the views of medical ethicists about medical futility, withdrawing/withholding treatment, ordinary/extraordinary interventions, and the doctrine of double effect

Design, subjects and setting–A 138-item attitudinal questionnaire completed by 469 UK nurses studying the Open University course on “Death and Dying” was compared with a similar questionnaire administered to 759 US nurses and 687 US doctors taking the Hastings Center course on “Decisions near the End of Life”.

Results–Practitioners accept the relevance of concepts widely disparaged by bioethicists: double effect, medical futility, and the distinctions between heroic/ordinary interventions and withholding/ withdrawing treatment. Within the UK nurses' group a “rationalist” axis of respondents who describe themselves as having “no religion” are closer to the bioethics consensus on withholding and withdrawing treatment.

Conclusions—Professionals' beliefs differ substantially from the recommendations of their professional bodies and from majority opinion in bioethics. Bioethicists should be cautious about assuming that their opinions will be readily accepted by practitioners.
Advance directives in psychiatric care: a narrative approach
Authors: Widdershoven Guy , Berghmans Ron
Published: July 2002

Advance directives for psychiatric care are the subject of debate in a number of Western societies. By using psychiatric advance directives (or so-called “Ulysses contracts”), it would be possible for mentally ill persons who are competent and with their disease in remission, and who want timely intervention in case of future mental crisis, to give prior authorisation to treatment at a later time when they are incompetent, have become non-compliant, and are refusing care. Thus the devastating consequences of recurrent psychosis could be minimised.

Ulysses contracts raise a number of ethical questions. In this article the central issues of concern and debate are discussed from a narrative perspective. Ulysses contracts are viewed as elements of an ongoing narrative in which patient and doctor try to make sense of and get a hold on the recurrent crises inherent in the patient's psychiatric condition.
Doctors' authoritarianism in end-of-life treatment decisions. A comparison between Russia, Sweden and Germany
Authors: Richter Jörg , Eisemann Martin , Zgonnikova Elena
Published: July 2002

Objectives—The study was performed in order to investigate how end-of-life decisions are influenced by cultural and sociopolitical circumstances and to explore the compliance of doctors with patient wishes

Participants and measurement—Five hundred and thirty-five physicians were surveyed in Sweden (Umeå), Germany (Rostock and Neubrandenburg), and in Russia (Arkhangelsk) by a questionnaire. The participants were recruited according to availability and are not representative. The questionnaire is based on the one developed by Molloy and co-workers in Canada which contains three case vignettes about an 82-year-old Alzheimer patient with an acute life-threatening condition; the questionnaire includes different levels of information about his treatment wishes. We have added various questions about attitudes determining doctors' decision making process (legal and ethical concerns, patient's and family wishes, hospital costs, patient's age and level of dementia and physician's religion).

Results—Swedish physicians chose fewer life-prolonging interventions as compared with the Russian and the German doctors. Swedish physicians would perform cardiopulmonary resuscitation (CPR) in the event of a cardiac arrest less frequently, followed by the German doctors. More than half the Russian physicians decided to perform CPR irrespective of the available information about the patient's wishes. Level of dementia emerged as the most powerful determining attitude-variable for the decision making in all three countries.

Conclusions—The lack of compliance with patient wishes among a substantial number of doctors points to the necessity of emphasising ethical aspects both in medical education and clinical practice. The inconsistency in the treatment decisions of doctors from different countries calls for social consensus in this matter.
Individual autonomy and state involvement in health care
Authors: Rice Thomas
Published: July 2002

This article examines the ethical basis for government involvement in health care. It first provides the case for individual autonomy, focusing on the justifications–particularly ethical ones–for allowing individuals to make their own choices in health care, and to control more of their own resources in doing so. Next, it provides the opposite case–for abridging individual autonomy, and in particular, for redistributing resources from those who are well off to those who are not. The overriding reason for favouring the latter case, which trumps the notion of individual autonomy, is to ensure that individuals who are at a disadvantage have an equal probability of attaining good health.
Lung function, biological monitoring, and biological effect monitoring of gemstone cutters exposed to beryls
Authors: Wegner Ralf , Heinrich-Ramm Regine , Nowak Dennis , Olma Karin , Poschadel Bernd , Szadkowski Dieter
Published: July 2002

OBJECTIVES

Gemstone cutters are potentially exposed to various carcinogenic and fibrogenic metals such as chromium, nickel, aluminium, and beryllium, as well as to lead. Increased beryllium concentrations had been reported in the air of workplaces of beryl cutters in Idar-Oberstein, Germany. The aim of the survey was to study the excretion of beryllium in cutters and grinders with occupational exposure to beryls—for example, aquamarines and emeralds—to examine the prevalence of beryllium sensitisation with the beryllium lymphocyte transformation test (BeLT), to examine the prevalence of lung disease induced by beryllium, to describe the internal load of the respective metals relative to work process, and to screen for genotoxic effects in this particular profession.

METHODS

In a cross sectional investigation, 57 out of 100 gemstone cutters working in 12 factories in Idar-Oberstein with occupational exposure to beryls underwent medical examinations, a chest radiograph, lung function testing (spirometry, airway resistance with the interrupter technique), and biological monitoring, including measurements of aluminium, chromium, and nickel in urine as well as lead in blood. Beryllium in urine was measured with a newly developed direct electrothermal atomic absorption spectroscopy technique with a measurement limit of 0.06 μg/l. Also, cytogenetic tests (rates of micronuclei and sister chromatid exchange), and a BeLT were performed. Airborne concentrations of beryllium were measured in three factories. As no adequate local control group was available, the cutters were categorised into those with an exposure to beryls of >4 hours/week (group A) and ⩽4 hours/week (group B).

RESULTS

Clinical, radiological, or spirometric abnormalities indicating pneumoconiosis were detected in none of the gemstone cutters. Metal concentrations in biological material were far below the respective biological limit values, and beryllium in urine was only measurable in subjects of group A. Cytogenetic investigations showed normal values which were independent of the duration of beryllium exposure. In one subject, the BeLT was positive. Beryllium stimulation indices were significantly higher in subjects with detectable beryllium in the urine than in those with beryllium concentrations below the detection limit (p<0.05). In one factory, two out of four measurements of airborne beryllium concentrations were well above the German threshold limit value of 2 μg/m3(twofold and 10-fold), and all gemstone cutters working in this factory had measurable beryllium concentrations in urine.

CONCLUSION

No adverse clinical health effects were found in this cross sectional investigation of gemstone cutters working with beryls. However, an improvement in workplace hygiene is recommended, accompanied by biological monitoring of beryllium in urine.
Lung cancer in Yorkshire chrome platers, 1972–97
Authors: Sorahan Tom , Harrington J Malcolm
Published: July 2002

OBJECTIVES

To investigate mortality from lung cancer in chrome platers, a group exposed to chromic acid.

METHODS

The mortality of a cohort of 1087 chrome platers (920 men, 167 women) from 54 plants situated in the West Riding of Yorkshire, United Kingdom, was investigated for the period 1972–97. All subjects were employed as chrome platers for ⩾3 months and all were alive on 31 May 1972. Mortality data were also available for a cohort of 1163 comparison workers with no known occupational exposure to chrome compounds (989 men, 174 women). Information on duration of chrome work and smoking habits collected for a cross sectional survey carried out in 1969–72 were available for 916 (84.3%) of the chrome platers; smoking habits were available for 1004 (86.3%) comparison workers. Two analytical approaches were used, indirect standardisation and Poisson regression.

RESULTS

Based on serial mortality rates for the general population of England and Wales, significantly increased mortality from lung cancer was observed (obs) in male chrome platers (obs 60, expected (exp) 32.5, standardised mortality ratio (SMR) 185, p<0.001) but not in male comparison workers (obs 47, exp 36.9, SMR 127). Positive trends were not shown for duration of employment exposed to chrome, although data on working after 1972 were not available.

CONCLUSIONS

Confident interpretation is not possible but occupational exposures to hexavalent chromium may well have been involved in the increased mortality from lung cancer found in this cohort of chrome platers.
Suicide in the farming community: methods used and contact with health services: Table 1
Authors: Booth Nicholas , Briscoe Martin , Powell Roy
Published: July 2002

Farmers have a high rate of suicide (1% of suicides in England and Wales). This study sought to test whether farmers would be less likely to have been in contact with primary or mental health services before death due to their reluctance to seek help. The study also sought to identify other characteristics that differentiated suicide among male farmers from other professional groups. A retrospective case-control design was used comparing male farmers with an age and sex matched control group. Cases were all members of the farming community within the Exeter Health District on whom suicide or open verdict had been recorded between 1979 and 1994. 63 Cases were identified and entered into the study. Controls were non-farmers with the same verdict who were matched for age (5 year age bands) sex and social class. Farmers were significantly more likely to use firearms to kill themselves (42% of farmersv11% controls). They were less likely to use a car exhaust or to die by poisoning (9% farmersv50% controls). Farmers were significantly less likely to leave a suicide note (21% farmersv41% controls). There was no significant difference between farmers and controls for numbers in contact with their general practitioner or mental health services in the 3 months before death. There may be some differences in help seeking behaviour between farmers and the general population as over 30% of farmers presented with exclusively physical symptoms. General practitioners should consider depressive and suicidal intention in farmers presenting with physical problems. When depression is diagnosed consideration should be given to the temporary removal of firearms as the high rate of suicide in the farming community may be strongly influenced by access to means.
Radiological progression and its predictive risk factors in silicosis
Authors: Lee H S , Phoon W H , Ng T P
Published: July 2002

OBJECTIVES

To investigate the risk factors predicting radiological progression in silicosis in a prospective cohort study of patients with silicosis who were previously exposed to silica from granite dust.

METHODS

From among a total of 260 patients with silicosis contracted from granite work, 141 with available serial chestxray films of acceptable quality taken over a period of 2 to 17 (mean 7.5) years, were selected for study. Ninety four (66.7%) had ended exposure 5 or more years perviously (mean 10.1 years, maximum 28 years). Radiological progression was assessed by paired comparison of the initial and most recent radiographs, with two or more steps of increase in profusion of small opacities according to the 12 point scale of the International Labour Organisation (ILO) classification of radiographs of pneumoconiosis, taken from the majority reading by a panel of three independent readers.

RESULTS

Overall, 37% of patients with silicosis had radiological evidence of progression. From the initial radiographs, 24 (31.6%) of those with radiological profusion category 1, 15 (37.5%) of those with radiological profusion category 2, and 13 (52%) of those with complicated silicosis (including all seven with category 3 profusion of small opacities) showed radiological progression. As expected, progression was more likely to be found after longer periods of follow up (the interval between the two chestxray films) with a 20% increased odds of progression for every additional year of follow up. After adjustment for varying intervals of follow up, the probability of radiological progression was found to be significant if large opacities were present in the initial chestxray film. Progression was also less likely to be found among those who had ended exposure to silica longer ago, although the result was of borderline significance (p=0.07). Tuberculosis was also associated with increased likelihood of progression (borderline significance).

CONCLUSIONS

There is a high probability of radiological progression in silicosis after high levels of exposure to granite dust among workers who were followed up for up to 17 years. A significant risk factor is the extent of radiological opacities in the initial chestxray film. The probability of progression is also likely to be reduced with longer periods after the end of exposure.
Effects of air pollution on changes in lung function induced by exercise in children with chronic respiratory symptoms
Authors: Timonen K L , Pekkanen J , Tiittanen P , Salonen R O
Published: July 2002

Objective: To investigate how daily variations in ambient air pollution, especially in particles, during the cold of winter affect repeated measurements of baseline lung function and exercise induced bronchial responsiveness among primary school children with chronic respiratory symptoms.

Methods: During alternate school weeks (mamimum five) from February to April 1994, 33 children took part in exercise challenge tests (n=141 tests). The exercise challenges were conducted outdoors in a school yard in the centre of Kuopio, Finland. Spirometric lung functions were measured indoors before the exercise, and 3 and 10 minutes after. Daily mean concentrations of PM10, black smoke (BS), NO2, CO, SO2, and particle size and numbers were monitored at a nearby fixed monitoring site.

Results: Daily variations in ambient air pollution were not associated with enhanced bronchial responsiveness. However, increased concentrations of BS, PM10, particle numbers, NO2, and CO were consistently associated with an impairment of baseline lung functions. The reductions in forced vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) were 0.5% and 0.6%, respectively, for each 10 μg/m3increase in BS (lag 2).

Conclusion: Particles derived from combustion affect baseline lung function rather than bronchial responsiveness among children with chronic respiratory symptoms.
Temporal and spatial relations between age specific mortality and ambient air quality in the United States: regression results for counties, 1960–97
Authors: Lipfert F W , Morris S C
Published: July 2002

Objective: To investigate longitudinal and spatial relations between air pollution and age specific mortality for United States counties (except Alaska) from 1960 to the end of 1997.

Methods: Cross sectional regressions for five specific periods using published data on mortality, air quality, demography, climate, socioeconomic status, lifestyle, and diet. Outcome measures are statistical relations between air quality and county mortalities by age group for all causes of death, other than AIDS and trauma.

Results: A specific regression model was developed for each period and age group, using variables that were significant (p<0.05), not substantially collinear (variance inflation factor <2), and had the expected algebraic sign. Models were initially developed without the air pollution variables, which varied in spatial coverage. Residuals were then regressed in turn against current and previous air quality, and dose-response plots were constructed. The validity of this two stage procedure was shown by comparing a subset of results with those obtained with single stage models that included air quality (correlation=0.88). On the basis of attributable risks computed for overall mean concentrations, the strongest associations were found in the earlier periods, with attributable risks usually less than 5%. Stronger relations were found when mortality and air quality were measured in the same period and when the locations considered were limited to those of previous cohort studies (for PM2.5and SO42-). Thresholds were suggested at 100–130 μg/m3for mean total suspended particulate (TSP), 7–10 μg/m3for mean sulfate, 10–15 ppm for peak (95th percentile) CO, 20–40 ppb for mean SO2.Contrary to expectations, associations were often stronger for the younger age groups (<65 y). Responses to PM, CO, and SO2declined over time; responses in elderly people to peak O3increased over time as did responses to NO2for the younger age groups. These results generally agreed with previous prospective cohort and ecological studies for comparable periods, age groups, and pollutants, but they also suggest that the results of those previous studies may no longer be applicable.

Conclusions: Spatially derived relations between air quality and mortality vary significantly by age group and period and may be sensitive to the locations included in the analysis.
Brittle Addison's disease: a new variation on a familiar theme
Authors: Gill Geoffrey V , Williams Gareth
Published: July 2002

Unstable and unpredictable disease control in diabetes or asthma, with frequent hospitalisations, is frequently referred to as ‘brittle’. We describe two cases of Addison's disease with recurrent hospitalisations in hypo-adrenal crises. Both patients had significant psychosocial disruption, and failure to take hydrocortisone replacement therapy was admitted in one and biochemically proven in the other. We propose that ‘brittle’ Addison's disease in these cases was due to poor treatment compliance related to psychosocial factors. These features have particular similarities with the syndrome of brittle diabetes.
Trends in diagnostic and therapeutic criteria in Graves' disease in the last 10 years
Authors: Escobar-Jiménez F , Férnandez-Soto M L , Luna-López V , Quesada-Charneco M , Glinoer D
Published: July 2002

A questionnaire describing a typical clinical case of Graves' disease and 10 variations on it was mailed to 70 Spanish units of endocrinology with the aim of assessing the new diagnostic and therapeutic trends for hyperthyroidism caused by Graves' disease in Spain and to compare the results obtained from previous studies carried out in Europe and Spain 10 years previously.

 Responses indicated that thyrotrophin (98%) and free thyroxine (88%) were the most used tests in the in vitro diagnosis of Graves' disease with a significant decrease in the use of total thyroxine, total triiodothyronine, and thyroglobulin in comparison with the surveys conducted 10 years previously in Europe and Spain. The presence of antibodies against the thyrotrophin receptor was the most frequently used immune marker in the diagnosis (78%) and the new use of antithyroperoxidase antibodies (36%) in diagnosis is noteworthy. Antithyroid drugs remain the treatment of choice (98%). Surgery was used mainly for large size goitres (33%) and radioiodine for recurrences after medical (61%) or surgical (80%) treatment.

 In conclusion, the responses obtained from this questionnaire provide insight into current specialist diagnostic and therapeutic practices with respect to Graves' disease and which could be of value to non-specialist units of endocrinology.
Status of antithyroid antibodies in Bangladesh
Authors: Hasanat M A , Rumi M A K , Alam M N , Hasan K Nadim , Salimullah M , Salam M A , Fariduddin M , Mahtab Hajera , Khan A K Azad
Published: July 2002

To study autoimmunity among thyroid diseases, 397 thyroid patients (age 30 (13) years; M/F 75/322) from two referral centres in Bangladesh and 94 healthy controls (age 30 (13) years; M/F 24/70) were studied for antimicrosomal and antithyroglobulin antibodies. Thyroid patients were clinically grouped as suspected autoimmune thyroid disease (AITD), non-autoimmune, or indeterminate groups (where no decision could be reached). Antimicrosomal antibody was strongly positive in 19.4% and weakly positive in 7.3% of patients but only 4.3% and 2.1% respectively in the controls (χ2 = 17.852; p = 0.000) whereas strong and weak positivity were 27.2% and 6.8% in patients compared with 8.5% and 4.3% respectively in the controls (χ2 = 16.916; p = 0.000) for antithyroglobulin antibody. Antibodies were positive in 63.0% with Hashimoto's thyroiditis, 36.4% with Graves' disease, and 44.7% with atrophic thyroiditis among the autoimmune group. In the non-autoimmune group antibodies were positive in 100% with multinodular hypothyroidism, 46.7% with subacute thyroiditis, 40.0% with suspected iodine deficiency goitre, 31.3% with toxic multinodular goitre, 30.8% with non-toxic solitary nodules, and 19.4% with simple diffuse goitre. None was positive for antimicrosomal antibody without being positive for antithyroglobulin antibody. The two antibodies strongly correlated in both patients (r = 0.977, p = 0.000) and controls (r = 0.986, p = 0.000). About 9% (36/397) of patients were mismatched with the final diagnosis on antibody measurement; most of them had Hashimoto's thyroiditis (33/36). Prevalence of AITD among thyroid patients was 48.36%. Specificity of antimicrosomal and antithyroglobulin antibodies were 93% and 87%. It was concluded that AITD is not uncommon in Bangladesh; antimicrosomal antibody is a useful marker for AITD and unless antibodies are checked, an appreciable number of patients with AITDs will remain undetected.
Genetic testing for inherited breast and ovarian cancer syndromes: important concepts for the primary care physician
Authors: Taylor M R G
Published: July 2002

The remarkable advances in the area of genetic testing are transforming the way clinical medicine is practised. In the case of the inherited breast-ovarian cancer syndrome the ability to engage in genetic testing of BRCA genes has raised novel issues over caring for patients who are at increased risk for these malignancies. The primary care physician is likely to play a pivotal role in identifying such persons. As only 10–15% of all breast cancers are caused by directly heritable mutations, cultivating the ability to identify those who may be at increased risk is an important skill for the primary care physician. Once it is established that an individual is at risk of BRCA mutation, the physician must understand the potential benefits and drawbacks of the various genetic BRCA tests. Taking such factors into account leads to the development of an appropriate plan for evaluation. Careful attention must also be paid to social and psychological issues that may affect patients and their families.
Aborted sudden cardiac death: a clinical perspective
Authors: Mazeika P
Published: July 2002

Sudden cardiac death in the community remains a major public health problem. The purpose of this article is to outline the epidemiology, pathophysiology, and immediate treatment of the cardiac arrest victim. The subsequent in-hospital diagnostic evaluation and management will then be discussed with an emphasis on the role of the implantable cardioverter-defibrillator. A systematic and evidence based approach should help to optimize patient care.
Living kidney donation: a comparison of laparoscopic and conventional open operations
Authors: Waller J R , Hiley A L , Mullin E J , Veitch P S , Nicholson M L
Published: July 2002

Laparoscopic donor nephrectomy has the potential to lessen the burden placed on live kidney donors. This study describes the first British comparison of donor morbidity and recovery following conventional open donor nephrectomy (ODN) and laparoscopic donor nephrectomy (LDN).

An initial series of LDN (n=20) was compared to a historical control group of ODN (n=34). Laparoscopic operations were performed via a transperitoneal approach, the kidney being removed through a 6–12 cm Pfannensteil incision. Open operations were performed using a retroperitoneal flank approach with resection of the 12th rib. Postoperatively, donors were managed with a patient controlled analgesia system.

LDN was associated with shorter mean (SD) inpatient stay (6 (2) v 4 (1) days; p=0.0001) and lower parenteral narcotic requirements (morphine 179 (108) v 67 (54) mg; p=0.0001). Laparoscopic donors started driving their cars sooner (2 (1.5) v 6 (4) weeks; p=0.0001) and returned to work more quickly (5 (3) v 12 (6) weeks; p=0.0001) than open nephrectomy donors. There were no differences in recipient serum creatinine levels at three months post-transplant but two recipients of transplant kidneys retrieved laparoscopically (10%) developed ureteric obstruction, whereas this complication did not occur after ODN (p=0.13).

LDN is associated with less postoperative pain and a substantial improvement in donor recovery times. It is not yet clear whether or not the outcome of the recipient kidney transplants are the same after ODN and LDN and much more experience is required before the place of this new technique can be defined.
Linking the physiological parameters of nitrate uptake with root morphology and topology in wheat (Triticum durum) and citrus (Citrus volkameriana) rootstock
Authors: Sorgonà A , Cacco G
Published: July 2002

The relationships between net nitrate uptake and root morphology and topology were investigated in wheat (Triticum durum Desf.) and citrus (Citrus volkameriana Ten. & Pasq.) seedlings in which root systems were modified by supplying different nutrient concentrations. Root morphological and topological changes were assessed by the number of root tips, the total root length, and the topological index. The net nitrate uptake process was evaluated during the induction and inhibition "feedback" regulation phases. In wheat seedlings, an increase in the external nitrate concentration, at either high or no phosphate, brought about an increase in number of root tips but did not affect total root length. A similar pattern was observed in citrus seedlings. Citrus seedlings also exhibited a shift in root branching pattern from herringbone to dichotomous with an increase in the external nitrate concentration. Conversely, wheat root topology was unaffected by nutrient treatments. A high level of nitrate supplied to wheat and citrus root systems reduced the full induction of the nitrate uptake rate and cumulative nitrate uptake but increased the half-time of reaching the full induction in net nitrate uptake (t1/2kind). Finally, a negative correlation between number of root tips and t1/2kindwas found in both species, while only in citrus seedlings was a positive correlation between t1/2kindand the topological index observed. The data suggest that root morphology has a greater effect on nitrate uptake than root topology.Key words: root morphology, root topology, net nitrate uptake, Citrus volkameriana, Triticum durum.