bluuebunny/crossref_metadata_2025_split huggingface dataset:
The G‐455A polymorphism of the fibrinogen BΒ‐gene relates to plasma fibrinogen in male cases, but does not interact with environmental factors in causing myocardial infarction in either men or women
Authors: Leander K. , Wiman B. , Hallqvist J. , Falk G. , De Faire U. 
Published: March 2003

Objectives.  To elucidate the association between a genetic polymorphism of the fibrinogen Bβ‐gene (G‐455A) and plasma fibrinogen levels and myocardial infarction (MI), respectively. In addition, to explore potential synergistic gene–environment interactions involving this polymorphism – until now, these data were unavailable.Design setting and subjects.  This case‐referent study of subjects aged 45–70 and living in Stockholm includes 834 men and 346 women with first‐time MI and 1034 men and 494 women randomly chosen as referents from the population. The cases were identified between 1992 and 1994 at the 10 emergency hospitals in Stockholm County.Main outcome measures.  MI and plasma fibrinogen levels.Results.  Crude analyses associated a high level of plasma fibrinogen with an increased risk of MI in both men and women. However, the relative risk decreased after controlling for other risk factors. The multivariate‐adjusted odds ratio (OR) (95% confidence interval) was 1.6 (1.2–2.3) for men and 1.5 (0.9–2.6) for women. Presence of the A allele at the G‐455A polymorphic site indicated higher plasma fibrinogen levels than the presence of the G allele, but the difference was only statistically significant for male cases. The ‐455A allele was not associated with an increased risk of MI. Furthermore, there were no strong indications of synergistic interaction between the G‐455A polymorphism and any of the environmental exposures considered.Conclusions.  In this large number of MI cases and referents, a high level of plasma fibrinogen was independently associated with increased risk of MI in men but not in women. The presence of the A allele at the G‐455A polymorphism of the fibrinogen Bβ‐gene was not associated with increased risk of MI, and no synergistic gene–environment interactions were detected.
The molecular genetics of cardiovascular disease: clinical implications
Authors: Stephens J. W. , Humphries S. E. 
Published: March 2003

Abstract. Stephens JW, Humphries SE (University College London, London). The molecular genetics of cardiovascular disease: clinical implications (Review). J Inter Med 2003; 253: 120–127.Coronary heart disease (CHD) is one of the main leading causes of death worldwide. CHD is a complex condition resulting from numerous gene–gene and gene–environment interactions. A large number of candidate genes exist. We review the evidence for the role of apolipoprotein E, lipoprotein lipase and interleukin‐6 in CHD and their interaction with smoking (an environmental risk). The main objective of genetic research into CHD is to provide a complete risk assessment, complementing the well‐studied traditional clinical and biochemical risk factors. Unravelling the role that functional gene polymorphisms play in determining risk, and in determining the levels of intermediate phenotypes is crucial to our understanding of the key metabolic pathways and physiology not only in the diseased, but also in the disease‐free state. The identification of new molecules (implicated in the relevant metabolic pathways) may subsequently lead to potential targets for therapeutic intervention. Improving our molecular understanding may also lead to the development of improved diagnostics. Sequencing of the entire genome is now a reality. Advances in technology, such as the development of ‘gene chips’ may allow us to study 100 000 genes at a time on a single chip. Such advances will amplify the power available to us in the realms of research into genetic physiology and interaction with environmental stimuli. The insights that these novel approaches may yield are eagerly awaited.
Fuzzy logic approaches to the analysis of HREM images of III–V compounds
Authors: Hillebrand R. 
Published: March 2003

It is known that high‐resolution electron microscopy (HREM) can provide quantitative information on the properties of crystalline materials. The HREM patterns of layered structures of III–V semiconductors vary with the chemical composition of the latter within the sublattices, which is also influenced by interdiffusion. Local variations of the crystal cell similarity are recorded for image analysis and compared with templates of known material composition.Of the advanced theories of data interpretation, the now well‐established fuzzy logic is highly suited for corresponding image processing techniques. Combining neighbouring image cell similarities, the underlying chemical composition is evaluated by applying fuzzy logic criteria of inference to masks of about 1 nm × 1 nm in size.The new approach can be used to localize regions of significant changes in composition, i.e. edge detection, and to determine the composition across the interface region. The methods introduced prove successfully applicable to simulated as well as to experimental images of AlAs/AlxGa1−xAs. Similarity/composition relations of nonlinear as well as nonmonotonic characteristics are studied to establish an alternative fuzzy logic approach.
Stereological estimation of the total number of ECL cells and related parameters using the smooth, vertical fractionator in the rat oxyntic mucosa
Authors: Bendtsen T. F. , Nyengaard J. R. , Grimelius L. , Gundersen H. J. G. 
Published: March 2003

SummaryDuring the last 10 years many attempts have been made to estimate the number of enterochromaffin‐like (ECL) cells in various animal studies. This is the first presentation of an unbiased stereological estimator of the total number of histamine‐positive ECL cells per rat and linked to estimators of related parameters: total volume of the oxyntic mucosa, total oxyntic mucosal surface area, total oxyntic serosal surface area, surface amplification factor, average thickness of the oxyntic mucosa, total and mean volume of the ECL cells, total number of oxyntic glands and pits, mean number of ECL cells per gland, and mean number of ECL cells and glands per oxyntic serosal surface area.This study is the first application of the smooth fractionator and includes a description of all sources of sampling variance in the smooth fractionator design with newly developed predictors.
On the influence of imaging conditions and algorithms on the quantification of surface topography
Authors: Wendt U. , Stiebe‐Lange K. , Smid M. 
Published: March 2003

SummaryThe influence of the microscopical magnification resulting in different voxel size and shape and of the algorithm on parameters used for the quantification of the surface topography is studied using topographical images obtained by confocal laser scanning microscopy. Fracture surfaces and wire‐eroded surfaces of steel were used as samples. The values obtained for the global topometry parameters normalized surface area, mean profile segment length and fractal dimension depend with different degrees on the microscopic magnification and on the algorithm used to compute these values. The topometry values can only be used to establish correlations between the topography and materials properties and for the modelling of surface generating processes if the imaging and computing details are given.
Impairment of cytoskeleton‐dependent vesicle and organelle translocation in green algae: combined use of a microfocused infrared laser as microbeam and optical tweezers
Authors: Holzinger A. , Monajembashi S. , Greulich K. O. , Lütz‐Meindl U. 
Published: March 2003

SummaryA Nd‐YAG laser at 1064 nm is used as optical tweezers to move intracellular objects and a laser microbeam to cause impairment of cytoskeleton tracks and influence intracellular motions in desmidiaceaen green algae. Naturally occurring migrations of large nuclei are inhibited in Micrasterias denticulata and Pleurenterium tumidum when the responsible microtubules are targeted with a laser microbeam generating 180 mW power in the focal plane. Impairment of the microtubule tracks appears to be irreversible, as the nucleus cannot pass the former irradiated area in Pleurenterium or remains abnormally dislocated in Micrasterias. The actin filament‐dependent movement of secretory vesicles and smaller particles can be manipulated by the same IR‐laser at 90 mW when functioning as optical tweezers. In Closterium lunula particles are displaced from their cytoplasmic tracks for up to 10 µm but return to their tracks immediately after removing the light pressure gained by the optical tweezers. The cytoplasmic tracks consist of actin filament cables running parallel to the longitudinal axis of Closterium cells as depicted by Alexa phalloidin staining and confocal laser scanning microscopy. Dynamics and extensibility of the cytoplasmic strands connecting particles to the tracks are also demonstrated in the area of large vacuoles which are surrounded by actin filament bundles. In Micrasterias trapping of secretory vesicles by the optical tweezers causes irreversible malformations of the cell shape. The vesicle accumulation itself dissipates within 30 s after removing the optical tweezers, also indicating reversibility of the effects induced, in the case of actin filament‐mediated processes.
Time‐resolved, three‐dimensional quantitative microscopy of a droplet spreading on solid substrates
Authors: Be’er A. , Lereah Y. 
Published: March 2003

SummaryA polarized microscope was used to study the spreading of mercury droplets on thin silver films. Using the differential interference contrast (DIC) method and semi‐quantitative measurements of the optical path difference (OPD), the three‐dimensional shape of the liquid droplet that wets the solid surface was constructed with an angle resolution of 1°. The evolution of the droplet shape was determined with a time resolution of 0.04 s. The quantitative results are compared with other wetting‐reaction systems. In particular, it is demonstrated that the droplet has a spherical‐cup shape during the entire wetting‐reaction process.
Effects of Adrenalectomy and of Mineralocorticoid Receptor/Glucocorticoid Receptor Ligands in Female Brown Norway and Fischer 344 Rats and F1 Hybrids
Authors: Marissal‐Arvy N. , Mormède P. 
Published: March 2003

AbstractOur previous studies suggested that the mineralocorticoid receptor (MR) of Brown Norway (BN) male rats is active independently of the presence of its ligands (i.e. constitutively active), and that glucocorticoid receptor (GR)‐mediated mechanisms are more efficient in BN than in Fischer 344 (F344) male rats. Such functional differences in corticosteroid receptors led us to compare the effect of adrenalectomy (ADX) and MR/GR‐mediated actions (treatments with deoxycorticosterone, DOC and RU 28362, respectively) on female rats from both strains, and, within the framework of a genetic study, to investigate how these differences were inherited in rats of the first generation (F1) born from the crossbreeding between BN and F344 inbred rats. This study extends our previous hypotheses of a constitutive activation of MR and of a greater efficiency of GR in males to females of the BN strain. In both strains, female rats were less sensitive to ADX and to treatments with DOC or RU 28362 than males. Globally, F1 hybrid BN×F344 rats inherited the functional characteristics of MR and GR of BN rats.
Ontogeny of Plurihormonal Cells in the Anterior Pituitary of the Mouse, as Studied by Means of Hormone mRNA Detection in Single Cells
Authors: Seuntjens E. , Hauspie A. , Vankelecom H. , Denef C. 
Published: March 2003

AbstractThe expression of mRNA of growth hormone (GH), prolactin (PRL), pro‐opiomelanocortin (POMC) and the common glycoprotein hormone α‐subunit (αGSU) was studied by means of single cell reverse transcriptase‐polymerase chain reaction in male mouse pituitary cells at key time points of fetal and postnatal development: embryonic day 16 (E16); postnatal day 1 (P1) and young‐adult age (P38). At E16, the hormone mRNAs examined were detectable, although only in 44% of total cells. Most of the hormone‐positive cells expressed only one of the tested hormone mRNAs (monohormonal) but 14% of them contained more than one hormone mRNA (plurihormonal cells). Combinations of GH mRNA with PRL mRNA, of αGSU mRNA with GH and/or PRL mRNA and of POMC mRNA with GH and/or PRL mRNA or αGSU mRNA were found. As expected, the proportion of hormone‐positive cells rose as the mouse aged. The proportions of plurihormonal cells followed a developmental pattern independent of that of monohormonal cells and characteristic for each hormone mRNA examined. Cells coexpressing POMC mRNA with GH or PRL mRNA significantly rose in proportion between E16 and P1, while the proportion of cells coexpressing GH and PRL mRNA markedly increased between P1 and P38. The occurrence of cells displaying combined expression of αGSU mRNA with GH and/or PRL mRNA did not significantly change during development. Remarkably, the population of cells expressing PRL mRNA only, was larger at E16 than at P1 and expanded again thereafter. In conclusion, the normal mouse pituitary develops a cell population that is capable of expressing multiple hormone mRNAs, thereby combining typical phenotypes of different cell lineages. These plurihormonal cells are already present during embryonic life. This population is of potential physiological relevance because development‐related factors appear to determine which hormone mRNAs are preferentially coexpressed. Coexpression of multiple hormone mRNAs may represent a mechanism to respond to temporally increased endocrine demands. The data also suggest that the control of combined hormone expression is different from that of single hormone expression, raising questions about the current view on pituitary cell lineage specifications.
Annexin‐1 (Lipocortin‐1)‐Immunoreactivity in the Folliculo‐Stellate Cells of Rat Anterior Pituitary: The Effect of Adrenalectomy and Corticosterone Treatment on Its Subcellular Distribution
Authors: Ozawa H. , Miyachi M. , Ochiai I. , Tsuchiya S. , Morris J. F. , Kawata M. 
Published: March 2003

AbstractIn the pituitary gland, annexin‐1 (lipocortin‐1) located in folliculo‐stellate (FS) cells has been advocated as one of the candidates for paracrine agents produced by FS cells that modulate the release of pituitary hormones. However, the expression and distribution pattern of annexin‐1 in FS cells under different circulating corticosteroid conditions has not been examined. Thus, by means of pre‐embedding immunoelectron microscopy, we investigated the expression of annexin‐1 in FS cells under different corticosteroid conditions. Annexin‐1‐immunoreactivity was observed in the cytoplasm; especially intense immunoreactivity was detected in the follicle surface of FS cells under control conditions. After adrenalectomy, annexin‐1‐immunoreactivity almost disappeared, but the immunoreactivity recovered with corticosterone replacement. The expression of glucocorticoid receptor immunoreactivity in the nucleus of FS cells also showed a similar pattern to annexin‐1 associated with the changes in the corticosteroid conditions. However, S‐100 immunoreactivity, a marker for FS cells, was not changed whatever the corticosteroid conditions. These results confirm that glucocorticoids regulate the annexin‐1 expression and demonstrate the translocation of annexin‐1 from intracellular to pericellular sites in the FS cells of the rat anterior pituitary gland.
Focal dystonia of the lateral pterygoid muscles treated with botulinum toxin
Authors: MOLLER E. , DALAGER T. , FUGLSANG‐FREDERIKSEN A. , PRYTZ S. , WERDELIN L. M. , BAKKE M. 
Published: March 2003

Oromandibular dystonia (OD) is a movement disorder characterized by involuntary activity of the craniofacial muscles. The present study deals with dystonic activity in the lateral pterygoid muscles (LP) of two women causing mandibular overbite, tiredness in the face and chewing and speech difficulties in one (HN, 61 years). In the other (BS, 37 years) OD was characterized by irregular lateral and protrusive jaw movements with and without tooth contact and frequent bilateral headache.By intra‐oral approach and without attempt to distinguish between the two heads the activity of LP was assessed by quantitative electromyography (EMG). Concentric needle electrodes were used for diagnosis and follow‐up, monopolar cannula electrodes for the EMG‐guided injection of botulinum toxin (Botox®, Allergan Inc., USA). In addition, activity in the temporal, masseter and digastric muscles was recorded with bipolar surface electrodes and mandibular movements were assessed graphically. Compared with reference values of postural activity, OD in both patients was associated with a marked increase in LP. Botox injections resulted in transient reduction of spontaneous and maximal activity, but it took two to three treatments with intervals of 3–4 months to obtain distinct subjective and clinical improvement. However, in HN followed for 18 months after breakthrough of treatment, the effect of the two latest injections lasted 8–9 months or three to four times longer than typical. Using quantitative EMG to locate the abnormal activity and to guide injections, treatment of LP dystonia with botulinum toxin is effective and safe.
The effect of local anaesthesia of the mandible on external‐load compensation during jaw closing
Authors: ABBINK J. H. , VAN DER BILT A. , VAN DER GLAS H. W. , BOSMAN F. 
Published: March 2003

In the past, chewing experiments with simulated food resistance have shown that jaw muscle responses to overcome the resisting load are mainly of sensory origin and only partly pre‐programmed, even if loading can be anticipated (Ottenhoff et al., 1992). It is unknown to what extent the several types of sensors involved in adjusting jaw‐muscle activity contribute to this response. Such sensors are, for example, periodontal receptors, sensitive to pressure on the teeth, and jaw muscle spindles, sensitive to changes in muscle length and therefore to changes in jaw position.We studied the activity of the masseter and temporal muscles during rhythmic open–close movements of the jaw. An electromagnetic device generated a load that simulated food resistance during jaw closing. Halfway the experiment, local anaesthesia was applied to the front part of the mandible with the aim to reduce possible feedback from periodontal receptors in this region to the jaw muscles.Anaesthesia did not affect the activity of the masseter muscles and their responses to the simulated food resistance. In the temporal muscles the reflex response (latency <120 ms) to the loading also did not change. However, with anaesthesia less temporal muscle activity was observed towards the end of jaw closing and during clenching. The results indicate that periodontal receptors in the mandible contribute little to the strong reflex responses of the jaw muscles to loading. Near the end of jaw closing and during clenching, when forces on the teeth are larger, output of periodontal receptors in the mandible may facilitate the activity of the temporal muscles. This facilitation may have been reduced by anaesthesia.
Task‐related electromyographic spectral changes in the human jaw muscles
Authors: FARELLA M. , VAN EIJDEN T. M. , BACCINI M. , MICHELOTTI A. 
Published: March 2003

The masticatory muscles differ in their fibre type composition. It can therefore be expected that their electromyographic (EMG) power spectra will differ during the performance of different bite force tasks. In the present study surface EMG activity was picked up from the masseter, and anterior and posterior temporalis muscles of nine adult subjects. Direction and magnitude of bite force were recorded using a three‐component force transducer. Bite forces were exerted in five different directions: vertical, forward, backward, to the right and to the left of the subject. Non‐vertical forces were kept at an angle of 15° from the vertical. Force levels of 25, 50, 100 and 200 N were exerted in each of the investigated directions. Data collected were analysed by means of a regression model for repeated measurements.It appeared that the mean power frequency (MPF) values of the posterior temporalis were significantly lower (P < 0·01) than those of the masseter and anterior temporalis. The MPF values of the masseter muscles decreased with an increase of bite force magnitude (P < 0·001) whereas the MPF values of the anterior and posterior temporalis did not change significantly (P > 0·05). The MPF values were significantly influenced by the direction of bite force (P < 0·01). The observed changes of MPF are possibly related to the recruitment of different fibre types and support the concept that the masticatory muscles behave heterogeneously.
Patients' assessment of efficiency of physiotherapeutic treatment modalities in temporomandibular disorders (TMD)
Authors: HUGGER A. , PAAK S. , BOLLMANN F. , STÜTTGEN U. 
Published: March 2003

Especially in the last 10 years the aetiological significance of occlusion for TMD was relativated and the search for other alternative therapeutic strategies was intensified. For the treatment of myogenous and arthrogenous problems in TMD different kinds of physiotherapy are reported. Our intention of the present pilot study was focused on patients' perception of efficiency of different physiotherapeutic modalities and in relation to splint therapy.A total of 187 patients of the TMD clinic in Düsseldorf were retrospectively asked to fill out a questionnaire with topics on physiotherapeutic home training programme (HTP), on professional physiotherapy (PP), on splint therapy (ST) and overall assessment of treatment effort (OATE). Eighty‐one questionnaires could be analysed and evaluated in relation to three diagnostic TMD subgroups (myogenous, arthrogenous and mixed).The HTP was positively assessed in 74%, PP in 70% and ST only in 38%. Fifty‐one per cent of patients could realize HTP regularly per day, 86% of patients could realise PP regularly per week. The majority of patients felt improvement after some weeks/months of HTP resp. PP. No significant relation could be detected between TMD subgroups and patients'assessment to HTP, PP, ST and OATE. Based on patients' assessment the results indicate that physiotherapeutic treatment modalities are highly efficient, whereas a differentiation between mentioned TMD subgroups does not seem to exist. A minority of patients (c. 20–25% of clinical cases) does not respond to dental‐occlusal and physiotherapeutic therapy very well. Therefore, a multidisciplinary psychosocial‐based treatment approach might be useful in these cases.