bluuebunny/crossref_metadata_2025_split huggingface dataset:
Impact of smokeless tobacco use on smoking in northern Sweden
Authors: Rodu B. , Stegmayr B. , Nasic S. , Asplund K. 
Published: March 2003

Abstract. Rodu B, Stegmayr B, Nasic S, Asplund K (University of Alabama at Birmingham, AL, USA and University Hospital, Umeå, Sweden). Impact of smokeless tobacco use on smoking in northern Sweden. J Intern Med 2002; 252: 398–404.Background and objectives. For many years Swedish men have had the world's lowest rates of smoking and smoking‐related mortality. Despite these facts, a thorough analysis of tobacco use patterns in Sweden has not been performed. The purpose of this study was to examine the prevalence and interaction of cigarette smoking and use of Swedish moist snuff (snus) in the population of northern Sweden.Design. The study cohort of 2998 men and 3092 women aged 25–64 was derived from the northern Sweden MONICA study, consisting of population‐based surveys in 1986, 1990, 1994 and 1999. Detailed information on tobacco use was used to develop prevalence data, and the prevalence ratio was used to compare rates amongst various subgroups.Results. Amongst men ever‐tobacco use was stable in all survey years at about 65%, but the prevalence of smoking declined from 23% in 1986 to 14% in 1999, whilst snus use increased from 22% to 30%. In women the prevalence of smoking was more stable in the first three surveys (∼27%) but was 22% in 1999, when snus use was 6%. In all years men showed higher prevalence of ex‐smoking than women. A dominant factor was a history of snus (PR = 6.18, CI = 4.96–7.70), which was more prevalent at younger ages.Conclusions. The recent transition from smoking to snus use amongst men, and incipiently amongst women, in northern Sweden is remarkable and relevant to the global discussion on strategies to reduce smoking.
Difficult treatment issues in sarcoidosis
Authors: Baughman R. P. , Lynch J. P. 
Published: March 2003

Abstract.Baughman RP, Lynch JP (University of Cincinnati, Cincinnati, OH, USA; University of Michigan, AnnArbor, MI, USA). Difficult treatment issues in sarcoidosis (Minisymposium).J Intern Med2003;253:41–45.The management of sarcoidosis includes several crucial decisions. Not all patients with sarcoidosis need treatment. At least a third of patients will never be treated. It is unclear whether asymptomatic patients ever need therapy, even if they have extensive lung disease. One reason that clinicians are reluctant to start therapy is that many patients who are started on corticosteroids have a difficult time getting off therapy, even after 2 years. In the chronic patient, alternatives to corticosteroids have been developed. These include drugs such as methotrexate, azathioprine and hydroxychloroquine. These agents have been the standard second line of therapy for patients with chronic disease. However, these drugs do not always work. In addition, they are associated with their own toxicities. Another group of sarcoidosis patients have also emerged. These are the refractory patients, who have progressive disease whilst on therapy. For these patients, new agents such as thalidomide and the monoclonal antibodies to tumour necrosis factor have been occasionally helpful. This paper reviews several important issues in the management of sarcoidosis.
A targeted approach significantly increases the identification rate of patients with undiagnosed haemochromatosis
Authors: Cadet E. , Capron D. , Perez A. S. , Crépin S. N. , Arlot S. , Ducroix J.‐P. , Dautréaux M. , Fardellone P. , Leflon P. , Merryweather‐Clarke A. T. , Livesey K. J. , Pointon J. J. , Rose P. , Harcourt J. , Emery J. , Sueur J. M. , Feyt R. , Robson K. J. H. , Rochette J. 
Published: March 2003

Abstract.  Cadet E, Capron D, Perez AS, Crépin SN, Arlot S, Ducroix J‐P, Dautréaux M, Fardellone P, Leflon P, Merryweather‐Clarke AT, Livesey KJ, Pointon JJ, Rose P, Harcourt J, Emery J, Sueur JM, Feyt R, Robson KJH, Rochette J (Université Jules Verne de Picardie, Amiens, France; MRC Molecular Haematology Unit, Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK; University of Oxford, Institute of Health Sciences, Oxford, UK; University of Cambridge, Institute of Public Health, Cambridge, UK; Biobanque de Picardie, Amiens, France; and Centre d'examens de santé de la Somme, Amiens, France). A targeted approach significantly increases the identification rate of patients with undiagnosed haemochromatosis. J Intern Med 2003; 253: 217–224.Objective.  To determine the optimal means of identifying patients with undiagnosed haemochromatosis.Design.  Case–control study where cases are defined by the presence of specific clinical diagnoses or symptoms.Setting.  Primary care patients were recruited from three Oxfordshire practices and secondary care patients were recruited from those patients attending specialist clinics in Amiens University Hospital.Subjects.  A total of 569 patients recruited via hospital clinics and 60 primary care patients (recruited from 4022 consultations) presenting with the following haemochromatosis associated conditions, diabetes, arthralgia/chronic fatigue, osteoporosis or arthropathy were studied. The control group, a total of 991 healthy volunteers, were recruited through a Health Appraisal Centre. Patients and controls were included in the study if they or their family members had not previously been diagnosed with hereditary haemochromatosis.Main outcome measures.  Serum ferritin concentration, transferrin saturation (Tsat) and presence of HFE mutations, C282Y and H63D. The check‐up in controls consisted of a questionnaire, clinical examination, biochemical tests and screening for the presence of the C282Y and H63D mutations.Results.  Patient groups presenting with unstable diabetes or chronic fatigue and arthralgia together with a raised serum ferritin concentration showed an enrichment in the haemochromatosis‐associated genotype HH/YY, odds ratio (OR) = 40.1, confidence interval (CI) = 8.0–202.1 and OR = 103, CI = 22.9–469.7, respectively.Conclusion.  Patients presenting to hospital clinics with haemochromatosis associated conditions should be screened biochemically for iron overload. Only those with a serum ferritin >300 μg L−1 or Tsat >40% should subsequently go on to be genotyped for HFE mutations. The patients at greatest risk of having undiagnosed haemochromatosis are those presenting with unstable diabetes, or fatigue and/or arthralgia in the absence of any other explanation.
Fever of unknown origin in adults: 40 years on
Authors: Knockaert D. C. , Vanderschueren S. , Blockmans D. 
Published: March 2003

Abstract.  Knockaert DC, Vanderschueren S, Blockmans D. (Gasthuisberg University Hospital, Leuven, Belgium). Fever of unknown origin in adults: 40 years on (Review). J Intern Med 2003; 253: 263–275.A revision of the criteria of fever of unknown origin (FUO), established in 1961, is desirable because of important evolutions in medical practice and the emergence of new patient populations. The development of rapid laboratory tests and powerful diagnostic tools, such as ultrasonography, computed tomography and magnetic resonance imaging often makes hospitalization unnecessary and new categories of patients such as those with HIV infection, neutropenia, immunosuppression and nosocomial illness require an approach different from classical FUO. The more then 200 reported causes of FUO can be classified into four diagnostic categories; infections, tumours, noninfectious inflammatory diseases (NIID) and miscellaneous. A uniform classification system is highly wanted to allow comparison between different series. The reports of the 1990s show slight changes in the distribution of causes, namely less infections, less tumours, more NIID and more undiagnosed cases. A uniform diagnostic strategy cannot be determined. The initial investigation should be directed by potentially diagnostic clues revealed by extensive history, meticulous physical examination and a standard set of laboratory tests. 18Fluoro‐deoxy‐glucose‐positron‐emitted‐tomgraphy is a new valuable total body scintigraphy in the search for the site of origin of the fever. In view of the rather good long‐term prognosis, a wait‐and‐see strategy may be more appropriate than a systematic staged approach. Elderly patients and patients with episodic fever represent two specific groups of classical FUO that require a distinct approach. HIV‐associated, nosocomial and neutropenic FUO should be considered as separate clinical entities.
Imaging surface and submembranous structures with the atomic force microscope: a study on living cancer cells, fibroblasts and macrophages
Authors: Braet  , Seynaeve  , De Zanger  , Wisse  
Published: March 2003

Atomic force microscopy (AFM) has been used to image a wide variety of cells. Fixed and dried‐coated, wet‐fixed or living cells were investigated. The major advantage of AFM over SEM is the avoidance of vacuum and electrons, whereas imaging can be done at environmental pressure and in aqueous conditions. Evidence of the successful application of AFM in biological imaging is provided by comparing results of AFM with SEM and/or TEM. In this study, we investigated surface and submembranous structures of living and glutaraldehyde‐fixed colon carcinoma cells, skin fibroblasts and liver macrophages by AFM. Special attention was paid to the correct conditions for the acquisition of images of the surface of these cells, because quality SEM examinations have already been abundantly presented.AFM imaging of living cells revealed specific structures, such as the cytoskeleton, which were not observed by SEM. Membrane structures, such as ruffles, lamellipodia, microspikes and microvilli, could only clearly be observed after fixing the cells with 0.1% glutaraldehyde. AFM images of living cells were comparable to SEM images of fixed, dried and coated cells, but contained a number of artefacts due to tip–sample interaction. In addition, AFM imaging allowed the visualization of cytoplasmic submembranous structures without the necessity for further preparative steps, allowing us: (i) to follow cytoskeletal changes in fibroblasts under the influence of the microfilament disrupting agent latrunculin A; (ii) to study particle phagocytosis in macrophages. Therefore, in spite of the slow image acquisition of the AFM, the instrument can be used for high‐resolution real‐time studies of dynamic changes in submembranous structures.
Saving the photons: mapping X‐rays by position‐tagged spectrometry
Authors: MOTT R. B. , FRIEL J. J. 
Published: March 2003

Since the early years of X‐ray spectrometry in electron microscopes, mapping the locations of chemical elements has been important. The X‐rays needed in large numbers for this are rare, owing to poor production efficiency compared with electron signals, and at risk of loss by many mechanisms such as missing the limited solid angle of the detector, absorption before reaching the detector and pulse pile‐up conventional digital mapping hardware reduces the information contained in the X‐ray spectrum at each pixel to the itegrated counts from a few regions of interest.The acquisition technique of position‐tagged spectrometry eliminates the conflict between the desire to see full frame X‐ray images quickly versus the analytical advantages of having complete spectra for each pixel. As the beam is scanned rapidly relative to traditional X‐ray mapping, photons are counted in a virtual 3‐D multichannel analyser on disk, preserving both spatial and spectral information. Along with the sophisticated post‐processing allowed by storing an entire spectrum per pixel, a unique degree of dynamic interaction with the developing data is made possible by integrating many short scans instead of using a single long dwell time at each pixel.
Microstructural analysis of silicon carbide monofilaments
Authors: Shatwell R. A. , Dyos K. L. , Prentice C. , Ward Y. , Young R. J. 
Published: March 2003

In the development of monofilaments, a good understanding of the process/property relationships is essential. Transmission electron microscopy (TEM) is a powerful tool but too slow and expensive to be used routinely. Alternative, cheaper techniques have therefore been investigated. The microstructures of three SiC monofilaments (DERA Sigma SM1140+, Textron SCS‐6 and Ultra‐SCS) and some experimental samples were studied using a combination of TEM, electron microprobe analysis, Raman microprobe analysis, thermo‐gravimetric analysis (TGA) and differential scanning calorimetry (DSC). It was found that the Raman technique was complementary to TEM and easily identified the presence of amorphous C and Si. These could not be seen by electron or X‐ray diffraction techniques. DSC indicated the presence of free Si in the DERA Sigma SM1140+ monofilament by a distinctive peak at ∼1400 °C. TGA showed the reaction of monofilament components with gaseous species. The Textron SCS‐6 and Ultra species lost weight as C was oxidized to gaseous CO. By contrast, the Sigma monofilament gained weight from formation of SiO2 from the free Si. The separations of the transverse optical phonon peaks in the Raman spectra were correlated with the density of stacking faults in the SiC crystallites. This was similar in all monofilaments. Analysis of the polarization of the Raman scattering gave information on the orientation of crystallites. The crystallites in SM1140+ and SCS‐6 were orientated predominantly with the <111> parallel to the radius. Preliminary interpretation of the polarized Raman scattering from Ultra‐SCS indicated more than one orientation of crystallite. One possibility was a mixture of <111> and <110> directions parallel to the radius.
The role of tip plasmons in near‐field Raman microscopy
Authors: Milner R. G. , Richards D. 
Published: March 2003

The enhancement in electric field strength in the vicinity of a metal tip, through the excitation of plasma modes in the tip, is investigated using the finite difference time domain method; such tip enhancement has significant potential for application in scanning near‐field Raman microscopy. To represent an experimentally realistic geometry the near‐field probe is described by a conical metal tip with a spherical apex, with radii 20 nm and 200 nm considered, in close proximity to a glass substrate. Illumination through the substrate is considered, both at normal incidence and close to the critical angle, with the polarization in the plane of incidence. By modelling the frequency dependent dielectric response of the metal tip we are able to highlight the dependence on the scattering geometry of the nature of the electromagnetic excitations in the tip. In particular, the strongest electric field enhancement with the greatest confinement occurs for the excitation of modes localized at the tip apex, excited only for off‐normal incidence. Bulk modes excited in the tip also produce enhancement, although over a larger area and with significantly less enhancement than that of the localized modes; however, the excitation of bulk modes is independent of the angle of incidence.
A new approach for high‐pressure freezing of primary culture cells: the fine structure and stimulation‐associated transformation of cultured rabbit gastric parietal cells
Authors: Sawaguchi A. , Mcdonald K. L. , Karvar S. , Forte J. G. 
Published: March 2003

SummaryA newly designated procedure for high‐pressure freezing of primary culture cells provided excellent ultrastructure of rabbit gastric parietal cells. The isolated parietal cells were cultivated on Matrigel‐coated aluminium plates for conventional subsequential cryoimmobilization by high‐pressure freezing. The ultrastructure of different organelles (Golgi apparatus, mitochondria, multivesicular bodies, etc.) was well preserved compared to conventional chemical fixation. In detail, actin filaments were clearly shown within the microvilli and the subapical cytoplasm. Another striking finding on the cytoskeleton system is the abundance of microtubules among the tubulovesicles. Interestingly, some microtubules appeared to be associating with tubulovesicles. A large number of electron‐dense coated pits and vesicles were observed around the apical membrane vacuoles in cimetidine‐treated resting parietal cells, consistent with an active membrane uptake in the resting state. Immunogold labelling of H+/K+‐ATPase was seen on the tubulovesicular membranes. When stimulated with histamine, the cultured parietal cells undergo morphological transformation, resulting in great expansion of apical membrane vacuoles. Immunogold labelling of H+/K+‐ATPase was present not only on the microvilli of expanded apical plasma membrane vacuoles but also in the electron‐dense coated pits. The present findings provide a clue to vesicular membrane trafficking in cultured gastric parietal cells, and assure the utility of the new procedure for high‐pressure freezing of primary culture cells.
The Central Effects of Orexin‐A in the Hypothalamic‐Pituitary‐Adrenal Axis In Vivo and In Vitro in Male Rats
Authors: Russell S. H. , Small C. J. , Dakin C. L. , Abbott C. R. , Morgan D. G. A. , Ghatei M. A. , Bloom S. R. 
Published: March 2003

AbstractOrexin‐A is synthesized in the posterolateral hypothalamus and immunoreactive fibres project to many central nervous system structures, including the paraventricular nucleus, which is rich in corticotropin releasing factor (CRF) neurones and neuropeptide Y (NPY) innervation. We investigated the central effects of orexin‐A on the hypothalamic‐pituitary‐adrenal (HPA) axis by measuring plasma concentrations of corticosterone and adrenocorticotropic hormone (ACTH) in vivo. We explored the potential neuropeptide pathways involved by investigating the effects of orexin‐A on CRF, NPY, arginine vasopressin (AVP) and noradrenaline release from hypothalamic explants in vitro. Intracerebroventricular (i.c.v.) injection of orexin‐A (3 nmol) in male rats stimulated increases in plasma concentrations of corticosterone between 10 and 40 min after injection, and of plasma ACTH at 20 and 90 min after injection. Orexin‐A significantly stimulated CRF and NPY release from hypothalamic explants in vitro. Orexin‐A did not stimulate CRF release in the presence of the selective NPY Y1 receptor antagonist, BIBP3226. BIBP3226 alone did not alter CRF release from hypothalamic explants. Orexin‐A had no effect in vitro on the release of other neuropeptides, AVP and noradrenaline, involved in the central regulation of the HPA axis. These results suggest that orexin‐A is involved in activation of the HPA axis, and that these effects could be mediated via the release of NPY.
Effects of Melanocortin Receptor Ligands on Thyrotropin‐Releasing Hormone Release: Evidence for the Differential Roles of Melanocortin 3 and 4 Receptors
Authors: Kim M. S. , Small C. J. , Russell S. H. , Morgan D. G. A. , Abbott C. R. , AlAhmed S. H. , Hay D. L. , Ghatei M. A. , Smith D. M. , Bloom S. R. 
Published: March 2003

AbstractThe hypothalamic melanocortin system is important in the central regulation of food intake and body weight. We have previously demonstrated that intracerebroventricular administration of α‐melanocyte stimulating hormone (α‐MSH), a nonselective MC3 and MC4 receptor agonist, stimulated plasma thyroid‐stimulating hormone, and agouti‐related protein (AgRP), an MC3 and MC4 receptor antagonist, suppressed it. In this study, we investigated the effects of MC3 and MC4 receptor (MC3‐R and MC4‐R) selective agonists and antagonists on the release of thyrotropin‐releasing hormone (TRH) from hypothalamic explants in vitro. α‐MSH stimulated TRH release from the rat hypothalamic explants (α‐MSH 100 nM 230 ± 22.9% basal, P < 0.005). In contrast, γ2‐MSH, a selective MC3‐R agonist, suppressed TRH release (γ2‐MSH 10 µM 76.2 ± 7.4% basal, P < 0.05). AgRP (83‐132), a nonselective MC3/4‐R antagonist, induced no change in TRH release whilst JKC‐363 (cyclic [Mpr11, D‐Nal14, Cys18, Asp22‐NH2]‐β‐MSH 11‐22), a selective MC4‐R antagonist, suppressed it (JKC‐363 10 nM 57.2 ± 11.5% basal, P < 0.05). Both AgRP (83‐132) and JKC‐363 blocked α‐MSH stimulated TRH release but only AgRP (83‐132) blocked the inhibitory effect of γ2‐MSH on TRH release. These data suggest differential roles for the MC3 and MC4 receptors in TRH release; MC3‐R agonism inhibiting and MC4‐R agonism stimulating TRH release.
Variation in Reproductive Behaviour within a Sex:Neural Systems and Endocrine Activation
Authors: Rhen T. , Crews D. 
Published: March 2003

AbstractIntrasexual variation in reproductive behaviour, morphology and physiology is taxonomically widespread in vertebrates, and is as biologically and ecologically significant as the differences between the sexes. In this review, we examine the diverse patterns of intrasexual variation in reproductive behaviours within vertebrates. By illustrating the genetic, cellular, hormonal and/or neural mechanisms underlying behavioural variation in a number of species, another level of complexity is added to studies of brain organization and function. Such information increases our understanding of the unique and conserved mechanisms underlying sex and individual differences in behaviour in vertebrates as a whole. Here, we show that intrasexual variation in behaviour may be discrete or continuous in nature. Moreover, this variation may be due to polymorphism at a single genetic locus or many loci, or may even be the result of phenotypic plasticity. Phenotypic plasticity simply refers to cases where a single genotype (or individual) can produce (or display) different phenotypes. Defined in this way, plasticity subsumes many different types of behavioural variation. For example, some behavioural phenotypes are established by environmental factors during early ontogeny, others are the result of developmental transitions from one phenotype early in life to another later in life, and still other strategies are facultative with different behaviours displayed in different social contexts.
Physiological Concentrations of Melatonin and Corticosterone in Stress and their Relationship with Phagocytic Activity
Authors: Barriga C. , Martín M. I. , Ortega E. , Rodriguez A. B. 
Published: March 2003

AbstractThe aim of the present work was to investigate the possible connection between melatonin, corticosterone and the nonspecific immune response under both basal and stressed conditions. The concentrations used in the present study were as determined in an earlier work, and corresponded to the minimum and maximum concentrations of the hormones melatonin and corticosterone over one circadian cycle in mice subjected to stress and in a basal group of mice. The concentrations were 15 pg/ml and 90 pg/ml of melatonin and 50 ng/ml and 200 ng/ml of corticosterone for incubations of the basal group macrophages, and 15 pg/ml and 70 pg/ml and 200 ng/ml and 500 ng/ml of melatonin and corticosterone, respectively, for incubations of macrophages from the group of stressed mice. The results indicate that corticosterone stimulates antigen ingestion at all physiological doses tested in the macrophages from the unstressed mice. The greatest phagocytic stimulation was obtained in macrophages from mice in a basal situation, and which had been incubated with the diurnal concentrations of the two hormones (maximum corticosterone 200 ng/ml; minimum melatonin 15 pg/ml). When the macrophages were from stressed mice, neither corticosterone nor melatonin led to any change in their phagocytic activity.