bluuebunny/crossref_metadata_2025_split huggingface dataset:
Attitudes towards clinical research amongst participants and nonparticipants
Authors: Madsen S. M. , Mirza M. R. , Holm S. , Hilsted K. L. , Kampmann K. , Riis P. 
Published: March 2003

Abstract. Madsen SM, Mirza MR, Holm S, Hilsted KL, Kampmann K, Riis P (Copenhagen University Hospital in Herlev, Herlev, Denmark; Odense University Hospital in Odense, Odense C, Denmark; University of Manchester, Manchester, UK; Copenhagen University Hospital in Herlev, Herlev, Denmark; and Odense University Hospital in Odense, Odense C, Denmark). Attitudes towards clinical research amongst participants and nonparticipants. J Intern Med 2002; 251: 156–168. Objectives. To investigate attitudes to clinical research amongst cancer trial participants and nonparticipants, and to compare results with those from previous studies amongst participants in noncancer trials. Design. Trial participating respondents were given three questionnaires during the clinical trials. Respondents amongst patients declining randomization answered a single questionnaire. Setting. Participants and nonparticipants in randomized clinical cancer trials. Subjects. Forty‐one participants and 47 nonparticipants in cancer trials. Results. Altruistic motives of physicians to conduct medical research were highly rated. Attitudes towards clinical research were positive in all groups, with nonparticipant respondents being the least positive. Eight to nine tenths found scientific testing necessary before general health service implementation. Trial participants were, as compared with nonparticipating respondents, more positive towards both participation of self and others. Both personal and altruistic motives for participation were highly rated. Primary reasons for nonparticipation were fear of ‘the unknown’ and/or unease with randomization. Only a minority felt a moral problem created by declining trial participation. Respondents amongst noncancer participants were more satisfied with the information given than both cancer participants and cancer nonparticipants. Negative experiences in cancer participants generally dealt with frustration related to seeing too many physicians at check‐up appointments. Conclusion. Attitudes towards clinical research are generally positive even in cancer nonparticipants. Both personal and altruistic motives for participation were highly rated. A fear of ‘the unknown’ and resentments towards randomization were primary reasons to renounce participation. Seeing too many physicians at check‐up appointments seems to be an important factor for negative experiences in cancer trial participants.
A C‐1291G polymorphism in the α2A‐adrenergic receptor gene (ADRA2A) promoter is associated with cortisol escape from dexamethasone and elevated glucose levels
Authors: Rosmond R. , Bouchard C. , Björntorp P. 
Published: March 2003

Abstract. Rosmond R, Bouchard C, Björntorp P (Sahlgrenska University Hospital, Göteborg, Sweden; Pennington Biomedical Research Center, LA, USA). A C‐1291G polymorphism in the α2A‐adrenergic receptor gene (ADRA2A) promoter is associated with cortisol escape from dexamethasone and elevated glucose levels. J Intern Med 2002; 251: 252–257. Objectives. The objective of the current study was to examine the potential impact of a C → G substitution at position −1291 of the α2A‐adrenergic receptor gene (ADRA2A) promoter on obesity and estimates of insulin, glucose, and lipid metabolism as well as circulating hormones, including salivary cortisol in 284 unrelated Swedish men born in 1944. Main outcome measures. The subjects were genotyped by using PCR amplification of the promoter region of the ADRA2A gene followed by digestion with the restriction enzyme MspI. Results. The frequencies were 0.23 for allele C and 0.77 for allele G. The observed genotype frequencies were 45.8 and 54.2% for C/G and G/G, respectively. Heterozygotes (n=121) had significantly (P=0.009) higher salivary cortisol levels after 0.5 mg dexamethasone compared with G/G homozygotes (n=143). Fasting glucose was found to be significantly (P=0.017) higher in heterozygotes than in G/G homozygotes. The latter group had also a borderline significantly (P=0.080) higher mean diastolic blood pressure. These results were all adjusted for the potential confounding effect of body mass index (BMI) and waist‐to‐hip ratio (WHR). Other measurements such as BMI, WHR, abdominal sagittal diameter, total testosterone, insulin‐like growth factor I, serum leptin, fasting insulin and serum lipids were not different across the ADRA2A genotype groups. Conclusions. In conclusion, we have shown that an C → G polymorphism at position −1291 of the ADRA2A gene is associated with a subnormal cortisol response to dexamethasone, elevated glucose levels and perhaps increased diastolic blood pressure. The pathophysiology could involve an altered density of the α2A‐AR that destabilizes the sympathetic–hypothalamic–pituitary–adrenal systems in those with genetic vulnerability in the α2A‐adrenergic receptor gene promoter.
Prospects for chemoprevention of cancer
Authors: TAMIMI R. M. , LAGIOU P. , ADAMI H.‐O. , TRICHOPOULOS D. 
Published: March 2003

Tamimi RM, Lagiou P, Adami H‐O, Trichopoulos D (Harvard School of Public Health, Boston, MA, USA; University of Athens Medical School, Goudi, Athens, Greece; and Karolinska Institute, University of Stockholm, Stockholm, Sweden). Prospects for chemoprevention of cancer (Review). J Intern Med 2002; 251: 286–300.The recent progress in molecular biology and pharmacology has increased the likelihood that cancer prevention will rely increasingly on interventions collectively termed `chemoprevention'. Cancer chemoprevention is the use of agents to inhibit, delay or reverse carcinogenesis. A number of potential targets for chemoprevention have recently been identified. Many classes of agents including antioestrogens, anti‐inflammatories, antioxidants and other diet‐derived agents have shown a great deal of promise. In this review, we will begin by describing the general classes of chemopreventive agents and the mechanisms by which these agents act. We will then describe the opportunities that presently exist for chemoprevention of specific cancers.
Is lipoprotein(a) a predictor for survival in patients with established coronary artery disease? Results from a prospective patient cohort study in northern Sweden
Authors: GLADER C. AHLBECK , BIRGANDER L. SLUNGA , STENLUND H. , DAHLÉN G. H. 
Published: March 2003

Abstract.  Ahlbeck Glader C, Slunga Birgander L, Stenlund H, Dahlén GH (Umeå University, Umeå, Sweden). Is lipoprotein(a) a predictor for survival in patients with established coronary artery disease? Results from a prospective patient cohort study in northern Sweden. J Intern Med 2002; 252: 27–35. Objectives. Lipoprotein(a) [Lp(a)] is a known risk factor for the development of atherosclerosis. The aim of the present study was to test the importance of Lp(a) as a predictor for the further prognosis in patients with established coronary artery disease. Design.  A prospective patient cohort study was carried out. Setting and subjects.  The cohort consists of 1216 patients who were examined with coronary angiography at the University Hospital in Umeå, Sweden, because of stable effort angina. Main outcome measures.  Lipids, Lp(a), fibrinogen, antithrombin III (AT III), sedimentation rate and clinical data were registered at angiography. After a mean follow‐up time of 6.7 years information on survival was collected from the municipal census lists and death certificates were examined. Total mortality and mortality because of cardiovascular disease were both used as outcome variables in the survival analyses. Results.  The total mortality in the patient cohort was 16.4%. An Lp(a) level of 300 mg L−1 or more was found in 30% of the study population and was found to be an independent predictor for death. A high fibrinogen, a low AT III level, a depressed left ventricular function and a high coronary obstruction score were other significant independent predictors of death. Total cholesterol, HDL‐ and LDL‐cholesterol were not related to survival in this study, but a substantial proportion of the population probably received lipid‐lowering agents during the study period. Conclusions.  An Lp(a) level exceeding 300 mg L−1 indicates a poor further prognosis and may help to identify patients who probably need powerful secondary prevention programmes to improve their prognosis.
The association between leptin and proinsulin is lost with central obesity
Authors: Söderberg S. , AhrÉn B. , Eliasson M. , Dinesen B. , Olsson T. 
Published: March 2003

Abstract. Söderberg S, Ahrén B, Eliasson M, DinesenB, Olsson T (Umeå University, Umeå, Lund University and Luleå Hospital, Lund, Sweden; and Steno Diabetes Center, Gentofte, Denmark). The association between leptin and proinsulin is lost with central obesity. J Intern Med 2002; 252: 140–148.Objective.  Hyperproinsulinaemia and hyperleptinaemia are interrelated features of the insulin resistance syndrome that are linked to the prospective risk of cardiovascular diseases. Whether the association between leptin and proinsulin is different between groups displaying different degrees of risk for cardiovascular diseases is not known. We therefore examined this association in men versus women and in pre‐ versus postmenopausal women from a population‐based sample.Design and subjects.  Healthy subjects (n = 158; 85 men and 73 pre‐ and postmenopausal women) from the Northern Sweden Monitoring of Trends and Determinants in Cardiovascular Disease population were studied with a cross‐sectional design.Methods.  Anthropometric measurements (body mass index and waist circumference) and oral glucose tolerance tests were performed. Enzyme‐linked immunosorbent assays were used for the analyses of specific insulin and proinsulin, and radioimmunoassay for leptin. Insulin resistance and β‐cell function were calculated according to the homeostasis assessment model. Partial correlation coefficients adjusted for age and measures of adiposity were calculated and multiple linear regression analyses were performed with leptin as dependent variable.Results.  In nonobese men and premenopausal women and in obese postmenopausal women, leptin was significantly associated with proinsulin after stratification for waist circumference. Furthermore, a multivariate analyses taking age and measures of adiposity into account, showed that high fasting proinsulin was a significant predictor of high leptin in these groups. In contrast, this association was lost with increasing central obesity in men and premenopausal women.Conclusions.  This study shows that both the degree of adiposity and the hormonal milieu influence the association between circulating leptin and proinsulin in a normal population. Therefore, the insulin resistance syndrome seems to be characterized by lost association between leptin and proinsulin, which may be explained by dysfunction in the adipoinsular axis.
Tobacco use and cancer causation: association by tumour type
Authors: Kuper H. , Boffetta P. , Adami H.‐O. 
Published: March 2003

Abstract.  Kuper H, Boffetta P, Adami H‐O (London School of Hygiene and Tropical Medicine, London, UK; Karolinska Institutet, Stockholm, Sweden; and International Agency for Research on Cancer, Lyon, France). Tobacco use and cancer causation: association by tumour type (Review). J Intern Med 2002; 252: 206–224.In the second part of our review we describe the association between tobacco use and risk of specific cancer types. There is evidence for an established association of tobacco use with cancer of the lung and larynx, head and neck, bladder, oesophagus, pancreas, stomach and kidney. In contrast, endometrial cancer is less common in women who smoke cigarettes. There are some data suggesting that tobacco use increases the risk for myeloid leukaemia, squamous cell sinonasal cancer, liver cancer, cervical cancer, colorectal cancer after an extended latency, childhood cancers and cancer of the gall bladder, adrenal gland and small intestine. Other forms of cancer, including breast, ovarian and prostate cancer, are unlikely to be linked to tobacco use.
Major bleeding complications after cardiopulmonary resuscitation: impact of thrombolytic treatment
Authors: Kurkciyan I. , Meron G. , Sterz F. , Müllner M. , Tobler K. , Domanovits H. , Schreiber W. , Bankl H. C. , Laggner A. N. 
Published: March 2003

Abstract.  Kurkciyan I, Meron G, Sterz F, Müllner M, Tobler K, Domanovits H, Schreiber W, Bankl HC, Laggner AN (General Hospital of Vienna, University of Vienna, Vienna, Austria). Major bleeding complications after cardiopulmonary resuscitation: impact of thrombolytic treatment. J Intern Med 2003; 253: 128–135.Objective.  The risk of bleeding complications caused by thrombolysis in patients with cardiac arrest and prolonged cardiopulmonary resuscitation is unclear. We evaluate the complication rate of systemic thrombolysis in patients with out‐of‐hospital cardiac arrest caused by acute myocardial infarction, especially in relation to duration of cardiopulmonary resuscitation.Design.  The study was designed as retrospective cohort study, the risk factor being systemic thrombolysis and the end‐point major haemorrhage, defined as life‐threatening and/or need for transfusion. Over 10.5 years, emergency cardiac care data, therapy, major haemorrhage and outcome of 265 patients with acute myocardial infarction admitted to an emergency department after successful cardiopulmonary resuscitation were registered.Results.  We observed major haemorrhage in 13 of 132 patients who received thrombolysis (10%, 95% confidence interval 5–15%), five of these survived to discharge, none died because of this complication. Major haemorrhage occurred in seven of 133 patients in whom no thrombolytic treatment had been given (5%, 95% confidence interval 1–9%), two of these survived to discharge. Taking into account baseline imbalances between the groups, the risk of bleeding was slightly increased if thrombolytics were used (odds ratio 2.5, 95% confidence interval 0.9–7.4) but this was not significant (P = 0.09). There was no clear association between duration of resuscitation and bleeding complications (z for trend = 1.52, P = 0.12). Survival was not significantly better in patients receiving thrombolysis (odds ratio 1.6, 0.9–3.0, P = 0.12).Conclusions.  Bleeding complications after cardiopulmonary resuscitation are frequent, particularly in patients with thrombolytic treatment, but do not appear to be related to the duration of resuscitation. In the light of possible benefits on outcome, thrombolytic treatment should not be withheld in carefully selected patients.
Exercise stress testing, myocardial perfusion imaging and stress echocardiography for detecting restenosis after successful percutaneous transluminal coronary angioplasty: a review of performance
Authors: Dori G. , Denekamp Y. , Fishman S. , Bitterman H. 
Published: March 2003

Abstract.  Dori G, Denekamp Y, Fishman S, Bitterman H (Carmel Medical Center, Haifa, Israel; Israel Institute of Technology, Israel). Exercise stress testing, myocardial perfusion imaging and stress echocardiography for detecting restenosis after successful percutaneous transluminal coronary angioplasty: a review of performance (Review). J Intern Med 2003; 253: 253–262.When chest symptoms recur in a patient who underwent percutaneous transluminal coronary angioplasty (PTCA), it is necessary to rule out restenosis (R). Three main noninvasive tests suggest the presence of R: exercise stress test (XT), myocardial perfusion imaging (MPI) and stress echocardiography (s‐echo). The objectives of this review were: (1) to estimate the pretest probability of R as a function of time after PTCA in symptomatic patients and (2) to obtain an approximation of the diagnostic parameters of the XT, MPI and s‐echo for detecting R. A MEDLINE search (English‐language, years: 1980–2001) was conducted to identify studies examining post‐PTCA functional testing for diagnosing R. Data from the studies were pooled. Comparing studies was often difficult due to varying methodology in the studies.Pretest probability of R in symptomatic patients increases in a nonlinear fashion from 20% or less at 1 month, to nearly 90% at 1‐year postangioplasty. The approximated accuracy of the XT, MPI, and s‐echo for detecting R was 62, 82 and 84%, respectively. During the first month after PTCA, none of the noninvasive modalities is able to accurately detect R. Late (7–9 months) after PTCA, the pretest probability of R is high and therefore the noninvasive measure may be spared. Our analysis suggests that MPI and s‐echo should be preferred over the XT for diagnosing R.
Hyperhomocysteinaemia is associated with coronary events in type 2 diabetes
Authors: Becker A. , Kostense P. J. , Bos G. , Heine R. J. , Dekker J. M. , Nijpels G. , Bouter L. M. , Stehouwer C. D. A. 
Published: March 2003

Abstract.  Becker A, Kostense PJ, Bos G, Heine RJ, Dekker JM, Nijpels G, Bouter LM, Stehouwer CDA (VU University Medical Center, Amsterdam, the Netherlands). Hyperhomocysteinaemia is associated with coronary events in type 2 diabetes. J Intern Med 2003; 253: 293–300.Objectives.  Amongst nondiabetic individuals, a high serum homocysteine concentration is an independent but relatively weak risk factor for coronary events. However, it is not known whether homocysteine increases risk of coronary events in type 2 diabetes. Therefore, we examined the combined effect of homocysteine and type 2 diabetes on risk of fatal and nonfatal coronary events.Subjects.  We assessed the 10‐year risk of coronary events associated with homocysteine amongst diabetic (n = 140) and nondiabetic (n = 361) individuals.Design.  We did this in the Hoorn Study, a population‐based study of glucose tolerance and related complications in Caucasian men and women aged 50–75 years.Results.  The incidence rate for coronary events was 2.63 (29 of 140) per 100 person‐years amongst diabetic and 1.29 (42 of 361) amongst nondiabetic individuals. Amongst diabetic individuals, risk of coronary events increased 28% for each 5‐μmol L−1 increment of homocysteine (hazard ratio, 1.28; 95% CI, 1.02–1.58). This risk was independent of age, sex, hypertension, total cholesterol, HDL‐cholesterol, cigarette smoking, body mass index and glomerular filtration rate. In nondiabetic participants, homocysteine was not associated with an increased risk of coronary events (hazard ratio for each 5‐μmol L−1 increment of homocysteine, 0.86; 0.52–1.41).Conclusions.  These data suggest that homocysteine is significantly associated with coronary events in individuals with type 2 diabetes, independent of traditional cardiovascular risk factors. Investigation of the effect of treatment with vitamin B on prognosis of individuals with type 2 diabetes is warranted.
Multiphoton microscopy in life sciences
Authors: König K. 
Published: March 2003

Near infrared (NIR) multiphoton microscopy is becoming a novel optical tool of choice for fluorescence imaging with high spatial and temporal resolution, diagnostics, photochemistry and nanoprocessing within living cells and tissues. Three‐dimensional fluorescence imaging based on non‐resonant two‐photon or three‐photon fluorophor excitation requires light intensities in the range of MW cm−2 to GW cm−2, which can be derived by diffraction limited focusing of continuous wave and pulsed NIR laser radiation. NIR lasers can be employed as the excitation source for multifluorophor multiphoton excitation and hence multicolour imaging. In combination with fluorescence in situ hybridization (FISH), this novel approach can be used for multi‐gene detection (multiphoton multicolour FISH). Owing to the high NIR penetration depth, non‐invasive optical biopsies can be obtained from patients and ex vivo tissue by morphological and functional fluorescence imaging of endogenous fluorophores such as NAD(P)H, flavin, lipofuscin, porphyrins, collagen and elastin. Recent botanical applications of multiphoton microscopy include depth‐resolved imaging of pigments (chlorophyll) and green fluorescent proteins as well as non‐invasive fluorophore loading into single living plant cells.Non‐destructive fluorescence imaging with multiphoton microscopes is limited to an optical window. Above certain intensities, multiphoton laser microscopy leads to impaired cellular reproduction, formation of giant cells, oxidative stress and apoptosis‐like cell death. Major intracellular targets of photodamage in animal cells are mitochondria as well as the Golgi apparatus. The damage is most likely based on a two‐photon excitation process rather than a one‐photon or three‐photon event. Picosecond and femtosecond laser microscopes therefore provide approximately the same safe relative optical window for two‐photon vital cell studies. In labelled cells, additional phototoxic effects may occur via photodynamic action. This has been demonstrated for aminolevulinic acid‐induced protoporphyrin IX and other porphyrin sensitizers in cells. When the light intensity in NIR microscopes is increased to TW cm−2 levels, highly localized optical breakdown and plasma formation do occur. These femtosecond NIR laser microscopes can also be used as novel ultraprecise nanosurgical tools with cut sizes between 100 nm and 300 nm. Using the versatile nanoscalpel, intracellular dissection of chromosomes within living cells can be performed without perturbing the outer cell membrane. Moreover, cells remain alive. Non‐invasive NIR laser surgery within a living cell or within an organelle is therefore possible.
Transmission electron microscopy of the interface between bone and pseudowollastonite implant
Authors: De Aza P. N. , Luklinska Z. B. , Anseau M. R. , Guitian F. , De Aza S. 
Published: March 2003

This paper reports on the structural morphology of the interface in vivo between implants composed of bioactive synthetic pseudowollastonite ceramic and bone in rat tibias. Thin sections of the interfaces were examined after 6 and 8 weeks of implantation period in a high resolution transmission electron microscope up to the lattice plane resolution level.The interfaces developed normal biological and chemical activities and remained reactive over the 8‐week period. The regions showing direct bone tissue bonding to the implant contained nanocrystals of hydroxyapatite‐like phase growing epitaxially across the interface in the [002] direction. The nanocrystals were also identified in the bone tissue formed in the interfacial area.The reactivity of the implant caused in the first instance formation of an amorphous woven type of bone, which transformed into a crystalline lamellar type containing collagen fibres. The Ca/P ratio of the interfacial region was found to be between 1.67 in the mature bone tissue formed about 5 µm from the interface, and 2.06 in the regions right at the interface.
Simultaneous phase and amplitude extraction from a single defocused image of a homogeneous object
Authors: Paganin D. , Mayo S. C. , Gureyev T. E. , Miller P. R. , Wilkins S. W. 
Published: March 2003

SummaryWe demonstrate simultaneous phase and amplitude extraction from a single defocused image of a homogeneous object. Subject to the assumptions explicitly stated in the derivation, the algorithm solves the twin‐image problem of in‐line holography and is capable of analysing data obtained using X‐ray microscopy, electron microscopy, neutron microscopy or visible‐light microscopy, especially as they relate to defocus and point projection methods. Our simple, robust, non‐iterative and computationally efficient method is applied to data obtained using an X‐ray phase contrast ultramicroscope.