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B Schneider

Publications and source records attributed to B Schneider.

At least 37 records · Page 2Linked to original sources
PubMed2005

Histomorphometry of tumour cell nuclei in astrocytomas using shape analysis, densitometry and topometric analysis.

Although tumour cell nuclei are important histological structures for grading of astrocytomas according to the WHO-classification of brain tumours, there is no reported morphometric study of astrocytomas which describes quantitatively the four main morphologic criteria of tumour cell nuclei: size, shape, texture (densitometric characteristics) and spatial relationships between the nuclei (topometric analysis). Using a set of morphometric parameters describing these criteria as well as the Ki67-proliferation index, 74 astrocytomas from 74 patients were studied by means of a digital image analysis system. The objective of the study was to test, if these morphometric parameters were sufficient for statistical discrimination between pilocytic astrocytomas WHO-grade I, astrocytomas grade II and anaplastic astrocytomas grade III. Our results showed a correct reclassification of 97.3% (72/74) of the cases with respect to the tumour grade by means of cross-validated discriminant analysis. Morphometric parameters characterizing nuclear shape (shape factors, Fourier-amplitudes) showed the most prominent differences between the three groups of cases, followed by topometric parameters (number of neighbours per nucleus, distances between the nuclei). Less pronounced differences between the tumour grades were found for parameters characterizing nuclear size, nuclear texture and the Ki67-proliferation index. In conclusion, the present morphometric procedure provided good discrimination between the tumour grades, supporting the view that histomorphometry of tumour cell nuclei could be a valuable tool for grading of astrocytomas.

Algorithms↗
PubMed2005

Definition of an uptake pharmacophore of the serotonin transporter through 3D-QSAR analysis.

The serotonergic system plays a critical role in a wide variety of physiological and behavioral processes. Dysregulation of the tightly controlled extracellular concentration of serotonin (5-hydroxytryptamine, 5-HT) appears to be at the origin of a host of metabolic and psychiatric disorders. Since the plasma membrane 5-HT transporter (SERT) is the major protagonist in regulating extracellular 5-HT concentration, SERT is the target of most drugs interacting with the serotonergic system. Unfortunately, some of the drugs towards SERT (e.g. amphetamine derivatives) interfere with cell homeostasis leading to cell toxicity. Developing new SERT ligands devoid of any side-effect represents a major priority in the treatment of 5-HT-associated pathologies. Here, we report structure-activity relationships (SAR) and three-dimensional QSAR (3D-QSAR) studies of a library of 121 compounds including 5-HT analogs, harmanes, benzothiazoles, indanones, amphetamine derivatives and substrate-type 5-HT releasers, with the goal of identifying the structural determinants crucial for SERT uptake. In the absence of data about the bioactive form of 5-HT, conformational analysis of 5-HT was performed using quantum chemistry calculations. This led to three 5-HT stable conformers with anti, -gauche and +gauche side-chain conformation. These conformers, used as templates for superimposition with all the library compounds, enabled the design of a reliable 6-points pharmacophore representative of SERT uptake activity. Molecular dynamics (MD) simulations performed with compounds that are efficiently, moderately, poorly or not transported by SERT allowed to assess the validity of our pharmacophore. Altogether, our data provide for the first time a reliable pharmacophore of SERT uptake activity, which may help to the design of new drugs targeting SERT.

Adult↗
PubMed2005

Tako-tsubo-like left ventricular dysfunction: clinical presentation, instrumental findings, additional cardiac and non-cardiac diseases and potential pathomechanisms.

Tako-tsubo-like left ventricular dysfunction phenomenon (TTP) has primarily been described in Japan and is characterized by transient left ventricular apical ballooning in the absence of coronary artery disease, associated with chest symptoms, electrocardiographic changes and minimal cardiac enzymes release. Aim of the present review is to summarize the current knowledge about TTP. TTP has been described predominantly in females. TTP occurs also outside Japan. Clinical symptoms comprise anginal chest pain, dyspnea and syncope. TTP occurs frequently after acute emotional or physical stress. Electrocardiographic ST- elevations may be present only for several hours. Then, normalization of the ST-segment occurs, followed by negative T waves, which persist for months. Arterial hypertension in TTP is found in up to 76%, hyperlipidaemia in up to 57%, diabetes mellitus in up to 12% and smoking in up to 18% of the patients. Several pathomechanisms have been proposed: myocardial stunning due to increased catecholamine levels, coronary vasospasm, atherosclerotic plaques rupture, myocarditis, catecholamine-induced hyperkinesis of the basal left ventricular segments and genetic. Patients with TTP should be monitored like patients with myocardial infarction. Care should be taken in the application of catecholamines and nitrates. Betablockers should be given in the acute and chronic phase, and possibly indefinitely to prevent recurrences. The prognosis of TTP is assumed to be good, but in the acute phase there are deaths due to multisystem organ failure, cardiogenic shock, ventricular fibrillation and ventricular rupture. The long term prognosis of TTP patients is largely unknown.

Humans↗
PubMed2004

Coenzyme Q10 serum levels in Huntington's disease.

Mitochondrial dysfunction contributes to the neurodegenerative process in Huntington's disease (HD). Coenzyme Q10 (CoQ10) enhances mitochondrial complex I activity and may therefore provide a therapeutic benefit in HD. We compared serum CoQ10 levels of previously untreated-and treated HD patients with those of healthy controls. CoQ10 did not significantly (ANCOVA F(dF 2, dF 55) = 2.57; p=0.086) differ between all three groups. However, the post hoc analysis showed no significant (p = 0.4) difference between treated HD patients ([CoQ10]: 88.12 [mean]+/-24.44 [SD], [range] 48.75-146.32 [pg/million platelets]) and controls (93.71+/-20.72, 65.31-157.94), however previously untreated HD patients (70.10+/-21.12, 38.67-106.14) had marked (p = 0.051) lower CoQ10 results than treated HD patients and controls (p = 0.017). Our results support that CoQ10 supplementation in HD patients may reduce impaired mitochondrial function in HD.

Adult↗
PubMed2004

[Significance of voice constitution as a predisposition for occupational voice disorders].

Occupational voice disorders have been increasing for years. The aim of this study was to examine whether a constitutionally weak voice should be regarded as a risk factor for developing such voice disorders. In a prospective study, 15 female teacher students with a normal vocal constitution were compared with 18 students with constitutionally weak voices during teaching practice. There was a significant difference in the mean fundamental frequency of both groups after teaching for 30 min. Students with constitutionally weak voices tended to have increased values. Taking into consideration the physiological aspects of an increasing fundamental frequency as a sign of vocal fatigue, a constitutionally weak voice has to be regarded as a potential risk factor for developing a voice disorder in vocally intensive occupations. To prevent future vocal problems by appropriate prophylactic intervention (i.e. voice therapy, introduction to vocal hygiene), a phoniatric examination of vocal constitution and endurance is recommended at the beginning of a voice dependent professional career.

Adolescent↗
PubMed2004

Synergistic interaction of two independent genetic loci causes extreme elevation of serum IgA in mice.

Understanding the molecular regulation of immunoglobulin A (IgA) expression is important as it plays an essential role in the first-line defence through mucosal secretions. Using inbred mouse strains, we identified two independent and dominant acting genetic loci that synergistically cause a 40-fold upregulation in serum IgA levels when introduced into the murine strain C57Bl/6J (B6). The first locus on chromosome 12 appears to be mainly responsible for the natural four-fold higher IgA levels in C3HeB/FeJ (C3H) compared to B6 mice. A second independent, chemically induced mutation on chromosome 5 caused a two-fold elevation when transferred from C3H into B6 mice. Both loci in concert effect a 40-fold elevation against the B6 genetic background. We determined the chromosomal localization of the two loci simultaneously by a one-step mapping process. The chemically induced mutation was identified within the immunoglobulin joining chain (IgJ) gene on chromosome 5. The major serum IgA modifier between the C3H and B6 was located on chromosome 12. This modifier region was mapped to a 350 kb region containing several immunoglobulin heavy-chain genes and the Ig alpha germline switch gene. We speculate that by interfering with both IgA expression and distribution, synergistic regulation of IgA is achieved.

Amino Acid Transport Systems, Neutral↗
PubMed2004

Reduction of clozapine-induced hypersalivation by pirenzepine is safe.

INTRODUCTION: Hypersalivation is known as a frequent, disturbing, and socially stigmatizing side effect of therapy with the atypical antipsychotic clozapine. It has been shown that the addition of the anticholinergic pirenzepine is able to reduce clozapine-induced hypersalivation, probably by blocking M4-receptors. Nevertheless, a pharmacokinetic interaction between both compounds cannot be excluded. METHODS: In this pilot study, 29 schizophrenic patients (ICD-10; 51.7 % female; age: 36.7 +/- 8.7 years [mean +/- SD]) were included. Serum concentrations of clozapine and its pharmacologically active metabolite N-desmethylclozapine were determined under steady-state conditions by automated HPLC with UV detection before and after addition of pirenzepine for 3 days. RESULTS: Significantly fewer patients reported hypersalivation after addition of pirenzepine (69 % vs. 34.5 %, P = 0.002). No significant differences of clozapine and N-desmethylclozapine serum levels before (329 +/- 181 ng/ml and 218.0 +/- 123.4 ng/ml, respectively) and 3 days after (336 +/- 215 ng/ml and 235.9 +/- 164.4 ng/ml, respectively) addition of pirenzepine were found. In three patients, however, clozapine serum levels increased; this was probably unrelated to pirenzepine. CONCLUSION: In conclusion, treatment of clozapine-induced hypersalivation with pirenzepine is a recommendable combination with low risk of additional side effects.

Adult↗
PubMed2004

'Candidatus Phytoplasma spartii', 'Candidatus Phytoplasma rhamni' and 'Candidatus Phytoplasma allocasuarinae', respectively associated with spartium witches'-broom, buckthorn witches'-broom and allocasuarina yellows diseases.

Spartium witches'-broom (SpaWB), buckthorn witches'-broom (BWB) and allocasuarina yellows (AlloY) are witches'-broom and yellows diseases of Spartium junceum (Spanish broom), Rhamnus catharticus (buckthorn) and Allocasuarina muelleriana (Slaty she-oak), respectively. These diseases are associated with distinct phytoplasmas. The SpaWB, BWB and AlloY phytoplasmas share <97.5 % 16S rDNA sequence similarity with each other and with other known phytoplasmas, including the closely related phytoplasmas of the apple proliferation group. Also, the SpaWB, BWB and AlloY phytoplasmas each have a different natural plant host. Based on their unique properties, it is proposed to designate the mentioned phytoplasmas as novel 'Candidatus' species under the names 'Candidatus Phytoplasma spartii', 'Candidatus Phytoplasma rhamni' and 'Candidatus Phytoplasma allocasuarinae', respectively.

DNA, Bacterial↗
PubMed2004

Retrolective, comparative, epidemiological cohort study with parallel groups design for evaluation of efficacy and safety of drugs with "well-established use".

UNLABELLED: The randomized controlled clinical trial (RCT) is accepted as the "golden standard" for the evaluation of efficacy and safety of new drugs. In contrast, to demonstrate efficacy and safety of drugs with "well-established use" that have been on the European Community market for long time, observational comparative epidemiological studies can be used according to the European drug regulation directive. However, because comparative epidemiological cohort studies can share some risk of bias with other nonrandomized observational study designs, there is a need for an approach that could effectively reduce the bias risk in this type of studies. STUDY OBJECTIVES: The purpose of the study was to evaluate the therapeutic efficacy and safety of a long-term complementary therapy of primary, non-metastatic breast carcinoma patients treated with standardized European mistletoe extract Iscador("mistletoe") in addition to the conventional adjuvant oncologic therapy, and compared to the control group treated with the conventional therapy alone. METHODS: The multicenter, comparative, retrolective, pharmaco-epidemiological cohort study with parallel groups design and randomly selected centers that routinely used both treatments was carried out according to Good Epidemiological Practice rules under a standard operating procedure control. The test group patients received the mistletoe extract treatment subcutaneously for at least 3 months, while the control group patients of the same cohort was exclusively treated with the conventional therapy. The patients were followed up for at least 3 years or until death. The primary endpoint of efficacy was the incidence of adverse reactions to the conventional oncologic therapy. Secondary endpoints were change from baseline of the symptoms associated with the disease and treatment as well as overall survival. All endpoints were adjusted to baseline imbalance and confounders. Safety was assessed descriptively by the number of patients with adverse drug reactions (ADRs) attributed to the test treatment. RESULTS: 1442 patients (710 tests and 732 controls) were eligible for the "per protocol" analysis of efficacy and safety. At baseline, the test group had a more advanced disease and worse prognostic factors profile. After a median follow-up of 66 vs. 60 months, and a median mistletoe therapy duration of 52 months, significantly fewer test group patients (16.2%) than control patients (54.0%) developed ADRs attributed to the conventional therapy [adjusted odds ratio, OR (95% confidence interval, CI), OR = 0.47 (0.32-0.67), p < 0.001]. In the test group, the majority of the symptoms disappeared more frequently, and overall mortality hazard was significantly lower [adjusted hazard ratio, HR (95% CI), HR = 0.46 (0.22-0.96), p = 0.038] than in the control group. Systemic ADRs attributed to the test treatment developed in 0.8%, and local ADRs in 17.3% of the patients. ADR severity was mild to intermediate. Tumor enhancement was not observed. CONCLUSIONS: Complementary therapy of patients with primary, non-metastatic breast carcinoma with the mistletoe extract Iscador was safe and in comparison to the control group within the same study cohort showed considerably fewer ADRs attributed to concurrent conventional therapy, reduced disease symptoms, and suggested a significant improvement of survival. Despite some methodical limitations that require careful study planning and conduction as well as critical interpretation, the applied study design seems suitable to evaluate the efficacy and safety of drugs with "well-established use", particularly in oncology.

Antineoplastic Agents, Phytogenic↗
PubMed2004

Elongated styloid process: when is it really elongated?

OBJECTIVE: The styloid process (SP) is often denoted as elongated when it is longer than 30 mm or 33 mm. These dimensions, based on early reports, do not respect the natural variation of the SP. The aim of this study is to investigate the natural variation of the length of the SP. Knowing this variation is a prerequisite for consistent terminology in anatomy and anthropology; it is essential for the classification of the SP as elongated on panoramic radiographs (PRs). MATERIALS AND METHODS: 1000 consecutive PRs of a normal population were retrieved from inactive files at the Dental School of the Hannover Medical University. Measurements of the length of the SPs were made directly on the radiographs from the caudal margin of the tympanic plate to the tip of the SP. RESULTS: On 521 of the 1000 PRs the length of the SP could be measured at least on one side. As there was no significant difference between distributions on the left and right side, both sides were combined to give a total of 837 measurements. The median was 28.0 mm, the interquartile range was from 23.0 mm to 36.0 mm. The distribution depends significantly on age and gender. The 90th percentile varies between 42 mm for women under 35 years and 49 mm for men aged over 35 years. CONCLUSIONS: The medians in our sample correspond to the thresholds for elongated SP quoted in the literature. Our results show that these thresholds are too low, since they are exceeded in 50% of normal patients. We propose that the SP should be considered to be elongated only if its length exceeds 45 mm, which corresponds to the average of the 90th percentiles for different sex and age groups.

Adult↗
PubMed2004

Serum level of VEGF-D in patients with primary lymphedema.

Recent studies have indicated that vascular endothelial growth factor-D (VEGF-D) stimulates lymphangiogenesis in humans. Furthermore, mutations of vascular endothelial growth factor receptor 3 (VEGFR-3) have been observed in families with hereditary lymphedema. The lack of stimulation of lymphangiogenesis could lead to production of even more VEGF-D to obtain stimulation of lymphangiogenesis resulting in a high serum level of VEGF-D. The aim of the present study was to compare the serum level of VEGF-D in patients with primary lymphedema with healthy controls. In a prospective study, the serum level of VEGF-D was determined by a solid phase ELISA in patients with primary lymphedema and compared with healthy controls. In the group of patients with primary lymphedema the serum level of VEGF-D was significantly higher compared with controls (p=0.0047). The increased levels of VEGF-D observed in the present study suggest that primary lymphedema may be based on defective stimulation of VEGFR-3.

Adult↗
PubMed2003

Change in patients' body weight after 12 months of treatment with glimepiride or glibenclamide in Type 2 diabetes: a multicentre retrospective cohort study.

AIMS/HYPOTHESIS: Our study compared the effects of glimepiride or glibenclamide treatment on body weight over 12 months of treatment in patients with Type 2 diabetes in routine outpatient practice. METHODS: This new retrospective study design used data from physicians in a restricted manner (retrolective). Data from case report forms from 520 patients from 91 randomly selected centres were assessed and covariance analysis performed. RESULTS: The influence of practice and patient characteristics on treatment assignment was low, reflecting the design of randomised controlled trials. Mean weight loss and reduction in body mass index from baseline to study endpoint were greater with glimepiride than with glibenclamide (-2.04+/-3.99 kg vs -0.58+/-3.65 kg, p<0.001; -0.71+/-1.38 kg/m(2) vs -0.20+/-1.28 kg/m(2), p<0.001). Duration of treatment at baseline influenced treatment outcome, but propensity score, sex, age and fasting blood glucose at baseline did not. Both glimepiride and glibenclamide led to decreases in fasting blood glucose (-2.43+/-0.24 mmol/l vs -3.03+/-0.24 mmol/l; p<0.001 vs baseline) and HbA(1c) (-1.23+/-0.09% vs -1.26+/-0.09%; p<0.001 vs baseline). Both treatments were associated with a decrease in serum total cholesterol and low density lipoprotein cholesterol. Triglycerides were lower in the glibenclamide group and high density lipoprotein cholesterol was higher in the glimepiride group only. CONCLUSIONS/INTERPRETATION: Initial treatment of Type 2 diabetes with glimepiride was associated with a significantly greater decrease in body weight and body mass index than treatment with glibenclamide, while providing equivalent glycaemic control.

Blood Glucose↗
PubMed2003

Implementation of the Vienna Hydrotherapy Group for Laryngectomees--a pilot study.

GOALS: Laryngectomy involves several problems for the individual, such as the need to cope with a stoma, adjustment to tracheostomal breathing, and the formation of a voice. Contact with water, resulting in aspiration, may prove fatal for laryngectomized patients in the absence of appropriate aids. The aim of this pilot study was to conduct a hydrotherapy group for laryngectomized patients and to evaluate its feasibility and outcome in relation to the goals of therapy. PATIENTS AND METHODS: Six male patients who had undergone laryngectomy were included in a pilot study. The patients underwent a structured hydrotherapy rehabilitation program (three times a week for 8 weeks), using a special underwater therapy device. The patients' posture was controlled by posturography and their endurance capacity by standard ergometry and the 6-min walk. The parameters of fatigue, expectoration, mobility, elasticity/flexibility, postural control/coordination, and general well being were registered on a visual analog scale (VAS). Quality of life was assessed by having the patients fill out the German version of the SF-36 Health Survey. MAIN RESULTS: Posturograpy findings showed an improvement of two subtests ( p<0.028). Exercise testing showed an improved endurance capacity ( p<0.028). The patients were able to walk a greater distance in the 6-min walking test ( p<0.028). The VAS also showed an improvement of endurance capacity ( p<0.028), fatigue ( p<0.028), expectoration ( p<0.043), mobility of the neck and shoulder ( p<0.027), flexibility ( p<0.027), postural control and coordination ( p<0.028), and general well being ( p<0.028). On the SF-36 Health Survey, the patients were improved in the items "Physical functioning" ( p<0.027), "Vitality" ( p<0.027) "Role-physical" ( p<0.026), and "Social functioning" ( p<0.043). CONCLUSIONS: A hydrotherapy group for laryngectomized patients proved to be safe, feasible, and effective in this pilot study.

Activities of Daily Living↗
PubMed2003

Molecular mapping of QTLs for Fusarium head blight resistance in spring wheat. II. Resistance to fungal penetration and spread.

Fusarium head blight (FHB, scab) causes severe yield and quality losses, but the most serious concern is the mycotoxin contamination of cereal food and feed. The cultivation of resistant varieties may contribute to integrated control of this fungal disease. Breeding for FHB resistance by conventional selection is feasible, but tedious and expensive. The aim of this work was to detect QTLs for combined type I and type II resistance against FHB and estimate their effects in comparison to the QTLs identified previously for type II resistance. A population of 364, F1 derived doubled-haploid (DH) lines from the cross 'CM-82036' (resistant)/'Remus' (susceptible) was evaluated for components of FHB resistance during 2 years under field conditions. Plants were inoculated at anthesis with a conidial suspension of Fusarium graminearum or Fusarium culmorum. The crop was kept wet for 20 h after inoculation by mist-irrigation. Disease severity was assessed by visual scoring. Initial QTL analysis was performed on 239 randomly chosen DH lines and extended to 361 lines for putative QTL regions. Different marker types were applied, with an emphasis on PCR markers. Analysis of variance, as well as simple and composite interval mapping, revealed that two genomic regions were significantly associated with FHB resistance. The two QTLs on chromosomes 3B (Qfhs.ndsu-3BS) and 5A (Qfhs.ifa-5A) explained 29 and 20% of the phenotypic variance, respectively, for visual FHB severity. Qfhs.ndsu-3BS appeared to be associated mainly with resistance to fungal spread, and Qfhs.ifa-5A primarily with resistance to fungal penetration. Both QTL regions were tagged with flanking SSR markers. These results indicate that FHB resistance was under the control of two major QTLs operating together with unknown numbers of minor genes. Marker-assisted selection for these two major QTLs appears feasible and should accelerate the development of resistant and locally adapted wheat cultivars.

Analysis of Variance↗
PubMed2003

Serum levels of osteoprotegerin increase with age in a healthy adult population.

Regulation of the balance of osteoblastic and osteoclastic activity is critical for the understanding of normal cell biology and forms the basis of metabolic bone diseases. Our study reports about influences of age and gender on serum levels of osteoprotegerin (OPG) and its association to other clinical parameters of bone metabolism in a precisely determined cohort of 1134 healthy subjects at 17 Austrian outpatient bone clinics, aged between 19 and 96 years (females n = 687, 50 +/- 21 years, 19-94, and males n = 447, 52 +/- 13.5 years, 24-96). Mean OPG serum levels for all participants were 50.83 +/- 51.47 pg/ml (n = 1134; median 36, 2-584) and we observed a sharp increase in females after 60 years and in males after 70 years of age. OPG serum levels increased significantly by age, 2.1 pg/ml in females and 1.9 pg/ml in males for every year (P < 0.0001). Correlation of OPG serum levels and several bone parameters of bone metabolism showed that OPG negatively correlated with serum iPTH (r = -0.14; P < 0.001) and with serum estradiol in females (r = -0.16, P < 0.0001). Bone mineral density measured by DXA method at the spine and at the hip did not correlate with OPG serum levels, except a borderline negative correlation at the trochanteric region (r = -0.1, P < 0.05) in females only. Our results show a significant increase of osteoprotegerin with age in healthy females and males but fluctuations do not predict bone mineral density under in vivo conditions.

Adult↗
PubMed2003

Assessment of vitamin D and calcium status in healthy adult Austrians.

BACKGROUND: Because there is reason to assume that also in Austria calcium and vitamin D malnutrition is wide-spread, we initiated a comprehensive study on calcium and vitamin D status in relation to bone health in a large group of the normal adult population. SUBJECTS AND METHODS: We assessed dietary calcium and vitamin D intake, serum concentrations of Ca2+, phosphate, alkaline phosphatase, 25(OH)D, 1,25(OH)2D, parathyroid hormone (PTH), follicle-stimulating hormone (FSH), sex hormones and bone mineral density (BMD) by double-energy X-ray absorptiometry at five different skeletal sites in 648 females and 400 males (age 21-76 years). RESULTS: Mean daily intake of vitamin D (101 IU, range 0.2-320) and calcium (569 mg, range 40-2170) was significantly less than the respective recommended dietary allowances. Two hundred and seventy-one (26%) individuals had hypovitaminosis D with serum 25(OH)D < 12 ng mL(-1), while serum Ca2+ was less than normal in 82 (7.8%) subjects. Multiple regression analysis revealed significant correlations between mean calcium intake and BMD in the femoral region in the men (r = 0.13, P < 0.05) though not in the women. No consistent data could be obtained for associations between BMD and vitamin D status, except for 25(OH)D and BMD at the spine in the men (r = 0.10, P < 0.05). 25(OH)D correlated negatively (P < 0.05) with age in the women (r = -0.11) and with PTH in the women (r = -0.11) and men (r = -0.16). Inversely, a significant (P < 0.001) age-related increase in PTH was observed in both sexes (men, r = 0.19; women, r = 0.14). CONCLUSIONS: Prevalence of hypovitaminosis D in adult Austrians is an imminent risk for development of secondary hyperparathyroidism with advancing age, and requires timely correction of nutritional deficits.

Absorptiometry, Photon↗