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G Meyer

Publications and source records attributed to G Meyer.

At least 19 recordsLinked to original sources
PubMed2006

Evaluation of a new disinfection procedure for ultrasound probes using ultraviolet light.

Following 183 ultrasound examinations, a randomized trial was conducted to compare three procedures for disinfection of probes under routine conditions: dry wiping with a soft, dry, non-sterile paper towel, antiseptic wiping with a towel impregnated with disinfectant spray and dry wiping followed by a 10 min ultraviolet C (UVC) cycle in a disinfection chamber. After ultrasonography, swabs were taken from transducer heads before and after cleaning and streaked onto plates that were then cultured. The number of colonies per plate was counted and organisms identified. The median microbial reduction was 100% for UVC, 98.4% for antiseptic wiping and 87.5% for dry wiping (P<0.001). The percentage of negative specimens was 88% for UVC, 16% for antiseptic wiping and 4% for dry wiping (P<0.0001). Microbial flora was isolated from 12 probes (6.6%) before cleaning, whereas specimens obtained after cleaning contained no pathogens except in one case after antiseptic wiping. UVC disinfection of ultrasound probe may provide a useful method for reducing the bacterial load under routine conditions.

Adult↗
PubMed2006

Understanding of diabetes prevention studies: questionnaire survey of professionals in diabetes care.

AIMS/HYPOTHESIS: Diabetes prevention studies have reported reductions of diabetes risk by up to 60%. Since the underlying metabolic changes are small, the clinical significance of this effect may be overestimated. The present survey explores the extent to which different formats of presenting study results may influence diabetes healthcare professionals' perceptions of the importance of intervention effects on diabetes risk. SUBJECTS, MATERIALS AND METHODS: Participants of three European diabetes conferences (160 nurse educators, 112 physicians, 27 other professionals) were presented with a questionnaire that included nine items, in which results from three diabetes prevention studies were presented in different ways. RESULTS: Participation rate was 96%. Effects were interpreted as important or very important by 92% (255/276) when results were presented as proportions of subjects with diabetes (14% intervention group, 29% control group), by 87% (248/285) when results were communicated as a risk reduction of 57%, by 39% (110/284) when the corresponding fasting plasma glucose values were presented (mean difference 0.3 mmol/l), and by 18% (52/283) when glycosylated haemoglobin values were used (6.0 vs 6.1%). Corresponding results of the three diabetes prevention studies were rated as being of identical importance by only 23, 13 and 16% of participants, respectively. CONCLUSIONS AND INTERPRETATION: Healthcare professionals rate the benefit of preventive interventions substantially higher when changes in diabetes risk are communicated rather than related glycaemic parameters. Transformation of continuous metabolic data into diagnostic categories may impair understanding of study effects.

Allied Health Personnel↗
PubMed2006

Hydrogen adsorption kinetics on Pd/Ce0.8Zr0.2O2.

Hydrogen adsorption on Pd/Ce(0.8)Zr(0.2)O(2) was studied by temperature-programmed reduction, volumetric measurements and IR spectroscopy. Hydrogen uptake and reduction rate at 353 K are strongly dependent on the hydrogen pressure. At relatively high hydrogen partial pressure, reduction involves PdO, the surface and a significant fraction of the bulk of the ceria based oxide. Formation of oxygen vacancies even at low temperature (<373 K) is observed. The hydrogen adsorption process is mainly irreversible, as is shown by an increase in the (2)F(5/2)-->(2)F(7/2) electronic transition of Ce(3+) with hydrogen pressure and surface dehydroxylation. This "severe" reduction has a negative effect on the subsequent hydrogen adsorption capability. The decrease of hydrogen uptake capacity and rate during adsorption can be associated with the partial loss of superficial OH and the presence of Ce(3+), which deactivates Pd electronically.

Adsorption↗
PubMed2006

Laparoscopic partial myectomy: an experimental reflux model.

BACKGROUND: A number of different surgical procedures have been described for the treatment of gastroesophageal reflux disease. Moreover, modifications and completely new techniques are being introduced on a regular basis. Nonetheless, in most cases of novel laparoscopic techniques profound experimental data have not been collected prior to their clinical introduction. Due to the lack of an animal model of inadequate esophageal sphincter function, most experimental studies on antireflux procedures were done on normally functioning esophageal sphincters. METHODS: It is well-known that myotomy alone cannot induce sphincter insufficiency in animal models. In addition, complete myectomy is associated with severe mortality and, therefore, is not useful as an experimental model. This study introduces a new model of laparoscopic partial in vivo myectomy. The procedure described here forms a myectomy of the esophagus using scissors and a sponge on the side of the greater gastric curvature. The size of the myectomy is approximately 6 x 1.5 cm and was successfully performed in a consecutive series of eight experimental animals (male German house pigs). RESULTS: Following an intensive team training on dead animals, the procedure was performed with success via the laparoscope in all study animals (n = 8). The sphincter pressure as determined by manometry was significantly reduced from 7.7 mmHg (range, 4.5-9.1; preoperative values) to 2.2 mmHg (range, 0-6.8; early postoperative values) and 2.3 mmHg (range, 0-3.7) at 8 weeks after surgery (p < 0.001). In addition, the length of the lower esophageal sphincter as well as the sphincter pressure vector volume were significantly reduced early as well as at 8 weeks after laparoscopic myectomy. Furthermore, endoscopy and reflux testing were pathologic compared with control animals. CONCLUSIONS: Laparoscopic partial myectomy results in complete sphincter insufficiency with only little procedure-related morbidity. This procedure allows for the experimental evaluation of surgical procedures on the gastroesophageal junction. Future modifications of surgical antireflux procedures can therefore be evaluated in an experimental setting prior to their clinical introduction.

Animals↗
PubMed2006

[Optimizing the nursing process by new management instruments. The Northern Germany Nursing Research Network].

The Northern Germany Nursing Research Network (Pflegeforschungsverbund Nord) has dedicated itself to developing management instruments intended to optimize the nursing process. It is coordinated by the administrative office of the Institute of Public Health and Nursing Research (Institut für Public Health und Pflegeforschung IPP, director: Prof. Dr. Stefan Görres), Department of "Interdisziplinäre Alterns- und Pflegeforschung", University of Bremen. Four partial projects are currently being worked on in two groups: Group A--"Deficient areas of nursing action": The projects belonging to this group are "Individual care-patterns of elderly people and their determinants" (University of Bremen) and "Mobility Restrictions in Nursing Homes-Multicentre Observational Study (MORIN)" (University of Hamburg). The purpose of these studies is to examine the relevance of quantitatively significant risk combinations from a nursing science perspective. Group B--"The generation and testing of nursing action management instruments": The projects in this area are "Nursing rounds as instruments of quality assurance in home-based care" (University of Applied Sciences, Bremen) and "Predicting the risk of falls, efficiency of standard scales in opposition to nursing assessment-Cluster-Randomised Controlled Trial (PROFESSION)" (University of Hamburg). These studies concentrate in a unique manner on the generation and testing of management/control instruments suitable for application to nursing action.

Activities of Daily Living↗
PubMed2006

[The German nursing expert standards: powerful instruments to improve nursing practice or of doubtful benefit?].

The German Network for the Development of Quality in Nursing has published so-called "National Expert Standards" on selected nursing issues. These are implemented into nursing practice, used by health authorities to evaluate the quality of nursing care and also for legal judgement. Evidence-based quality criteria for practice guidelines are currently not met. The expert standards lack rigorous methods for development, transparent reporting and clarity. Implementation tools to allow structured implementation are not provided. Vague recommendations offer various possibilities of interpretation. Effectiveness of the expert standards has not yet been proven. Future nursing guidelines should take into account international quality criteria.

Clinical Competence↗
PubMed2006

Epidemiological evaluation of the multifactorial aetiology of abfractions.

The purpose of this study was to determine risk indicators for the aetiology of abfractions (cervical wedge-shaped defects) on teeth using dental and medical variables obtained in a population-based sample of the cross-sectional epidemiological 'Study of Health in Pomerania' (SHIP). Medical history, dental, and sociodemographic parameters of 2707 representatively selected subjects 20-59 years of age with more than four natural teeth were checked for associations with the occurrence of abfractions using a two-level logistic regression model on a tooth and a subject level. The estimated prevalence of developing abfractions generally increased with age. The following independent variables were associated with the occurrence of abfractions: buccal recession of the gingiva, odds ratio (OR) = 6.7; occlusal wear facets of scores 1, 2 and 3, OR = 1.5, 1.9, 1.9; tilted teeth, OR = 1.4; inlays, OR = 1.6; toothbrushing behaviour, OR = 1.9 to 2.0 (two and three times a day versus once a day). First premolars had the highest estimated risk for developing abfractions, followed by the second premolars. Maxillary and mandibular teeth behaved similarly in terms of abfractions, with the exception of mandibular canines, which had a much lower estimated risk of incurring abfractions than did maxillary canines. The results of this analysis indicated that abfractions are associated with occlusal factors, like occlusal wear, inlay restorations, altered tooth position and tooth brushing behaviour. This study delivers further evidence for a multifactorial aetiology of abfractions.

Adult↗
PubMed2006

Indicators of lifetime endogenous estrogen exposure and risk of venous thromboembolism.

BACKGROUND: Lifetime estrogen exposure has been related to breast cancer risk, osteoporosis, and cardiovascular disease but data on venous thromboembolism (VTE) risk are limited. METHODS: Data from a hospital-based case-control study among 608 postmenopausal women (191 with a first episode of idiopathic VTE and 417 age-matched controls) were used to determine whether estrogen exposure, as assessed by age at menopause [classified as early (< or = 45 years), normal (46-54 years) and late menopause (> or = 55 years)] and parity, was associated with the risk of VTE. RESULTS: After adjustment for potential confounding variables, the risk of VTE was increased with each year's delay in the menopause [odds ratio (OR) = 1.06, 95% confidence interval (CI) = 1.02-1.10, P < 0.0075]. When compared with women with normal menopause used as a reference, the adjusted OR for VTE was 0.59 (95% CI = 0.36-0.97) and 2.53 (95% CI = 1.28-4.99) for women with early menopause and late menopause, respectively (P = 0.001). Adjusted OR for VTE was also higher for women with more than two children when compared with those with less than or equal to two children (1.56, 95% CI = 1.03-2.34, P = 0.03). The lowest risk of VTE was observed in women with early menopause and lower parity (adjusted OR = 0.60, 95% CI = 0.30-1.24), the highest risk was among women with late menopause who have had more than two children (adjusted OR = 3.41, 95% CI = 1.46-9.25). CONCLUSION: These results show that the longer exposure to endogenous estrogen is associated with an increased VTE risk.

Age Factors↗
PubMed2006

Obesity and risk of venous thromboembolism among postmenopausal women: differential impact of hormone therapy by route of estrogen administration. The ESTHER Study.

BACKGROUND: Oral estrogen use and elevated body mass index (BMI) increase the risk of venous thromboembolism (VTE). Recent data suggest that transdermal estrogen might be safe with respect to thrombotic risk. However, the impact of transdermal estrogen on the association between overweight (25 kg m(-2) < BMI < or = 30 kg m(-2)) or obesity (BMI >30 kg m(-2)) and VTE risk has not been investigated. METHODS: We carried a multicenter case-control study of VTE among postmenopausal women aged 45-70 years, between 1999 and 2005, in France. Case population consisted of women with a first documented idiopathic VTE. We recruited 191 hospital cases matched with 416 hospital controls and 62 outpatient cases matched with 181 community controls. RESULTS: The odds ratio (OR) for VTE was 2.5 [95% confidence interval (CI):1.7-3.7] for overweight and 3.9 (95% CI: 2.2-6.9) for obesity. Oral, not transdermal, estrogen was associated with an increased VTE risk (OR = 4.5; 95% CI: 2.6-7.7 and OR = 1.1; 95% CI: 0.7-1.7, respectively). Compared with non-users with normal weight, the combination of oral estrogen use and overweight or obesity further enhanced VTE risk (OR = 10.2; 95% CI: 3.5-30.2 and OR = 20.6; 95% CI: 4.8-88.1, respectively). However, transdermal users with increased BMI had similar risk as non-users with increased BMI (OR = 2.9; 95% CI: 1.5-5.8 and OR = 2.7; 95% CI: 1.7-4.5 respectively for overweight; OR = 5.4; 95% CI: 2.1-14.1 and OR = 4.0; 95% CI: 2.1-7.8 respectively for obesity). CONCLUSIONS: In contrast to oral estrogen, transdermal estrogen does not confer an additional risk of idiopathic VTE in women with increased BMI. The safety of transdermal estrogen on thrombotic risk has to be confirmed.

Administration, Cutaneous↗
PubMed2006

Clinical probability and alveolar dead space measurement for suspected pulmonary embolism in patients with an abnormal D-dimer test result.

BACKGROUND: Most patients with suspected pulmonary embolism (PE) have a positive D-dimer test and undergo diagnostic imaging. Additional non-invasive bedside tests are required to reduce the need for further diagnostic tests. OBJECTIVES: We aimed to determine whether a combination of clinical probability assessment and alveolar dead space fraction measurement can confirm or exclude PE in patients with an abnormal D-dimer test. METHODS: We assessed clinical probability of PE and alveolar dead space fraction in 270 consecutive in- and outpatients with suspected PE and positive D-dimer. An alveolar dead space fraction < 0.15 was considered normal. PE was subsequently excluded or confirmed by venous compression ultrasonography, spiral computed tomography and a 3-month follow-up. Radiologists were unaware of the results of clinical probability and capnography. RESULTS: PE was confirmed in 108 patients (40%). Capnography had a sensitivity of 68.5% (95% confidence interval [CI]: 58.9-77.1%) and a specificity of 81.5% (95% CI: 74.6-87.1%) for PE. Forty-five patients (16.6%) had both a low clinical probability and normal capnography (sensitivity: 99.1%, 95% CI: 94.9-100%) and 34 patients (12.6%) had both a high clinical probability and abnormal capnography (specificity: 100%, 95% CI: 97.7-100%). CONCLUSION: Capnography alone does not exclude PE accurately. The combination of clinical probability and capnography accurately excludes or confirms PE and avoids further testing in up to 30% of patients.

Capnography↗
PubMed2006

German dental faculty attitudes towards computer-assisted simulation systems correlated with personal and professional profiles.

BACKGROUND: Computer technology is increasingly used in practical training at universities. However, in spite of their potential, computer-assisted simulation (CAS) systems still appear to be underutilised. OBJECTIVES: To investigate the practical usage of CAS/computer-assisted learning (CAL) systems, the familiarity and level of use of CAS systems, as well as the acceptance of approved learning content and English as the language of instruction in CAS/CAL systems. METHODS: A survey was conducted in the Departments of Conservative Dentistry and Prosthetic Dentistry of all 32 dental schools in Germany. Besides investigating the usefulness of, familiarity with and level of current usage of CAS systems, the questionnaire also contained questions regarding each respondent's gender, age, academic rank, experience in academia and computer skills, all of which correlated with the responses. RESULTS: The response rate was 90% (112 out of 125). The use of CAS/CAL systems was considered 'partly' to 'very' useful for evaluating the acquisition of knowledge (83.9%), qualitative issues (73.2%) and processes (72.3%) of dental preparation exercises and complex treatment strategies. However, only about half the respondents reported that they knew of, and even fewer used, the following systems in preclinical or clinical training: EDUnet (KaVo, Germany) (46.3%/0.9 %), PREPassistant (KaVo, Germany) (50%/0.9%), or the DentSim system (DenX, Israel) (52.8%/1.9%). The virtual simulation system VRDTS-CP (Novint, USA), used by none of the respondents, was known to only 16.5%. Responders agreed at least partly to accept approved learning content (74.9%) and English as the language of instruction (82.1%) as the standards for CAS systems. CONCLUSION: The survey indicates a distinct discrepancy between a generally positive attitude towards the usefulness of computer technology for dental education, the level of familiarity with current computer systems and their actual use. However, two prerequisites for ultimately decreasing the cost and increasing the usage of CAS systems--the acceptance of approved learning content and English as the language of instruction in CAS systems--seem to be generally accepted by respondents.

Adult↗
PubMed2006

Computer-assisted learning and simulation systems in dentistry--a challenge to society.

INTRODUCTION: Computer technology is increasingly used in practical training at universities. However, in spite of their potential, computer-assisted learning (CAL) and computer-assisted simulation (CAS) systems still appear to be underutilized in dental education. MATERIALS AND METHODS: Advantages, challenges, problems, and solutions of computer-assisted learning and simulation in dentistry are discussed by means of MEDLINE, open Internet platform searches, and key results of a study among German dental schools. RESULTS: The advantages of computer-assisted learning are seen for example in self-paced and self-directed learning and increased motivation. It is useful for both objective theoretical and practical tests and for training students to handle complex cases. CAL can lead to more structured learning and can support training in evidence-based decision-making. The reasons for the still relatively rare implementation of CAL/CAS systems in dental education include an inability to finance, lack of studies of CAL/CAS, and too much effort required to integrate CAL/CAS systems into the curriculum. CONCLUSION: To overcome the reasons for the relative low degree of computer technology use, we should strive for multicenter research and development projects monitored by the appropriate national and international scientific societies, so that the potential of computer technology can be fully realized in graduate, postgraduate, and continuing dental education.

Computer Simulation↗
PubMed2005

S-CMC-Lys-dependent stimulation of electrogenic glutathione secretion by human respiratory epithelium.

Glutathione (GSH) is one of the most important defense mechanisms against oxidative stress in the respiratory epithelial lining fluid. Considering that GSH secretion in respiratory cells has been postulated to be at least partially electrogenic, and that the mucoregulator S-carbocysteine lysine salt monohydrate (S-CMC-Lys) can cause an activation of epithelial Cl(-) conductance, the purpose of this study was to verify whether S-CMC-Lys is able to stimulate GSH secretion. Experiments have been performed by patch-clamp technique, by high-performance liquid chromatography (HPLC) assay, and by Western blot analysis on cultured lines of human respiratory cells (WI-26VA4 and CFT1-C2). In whole-cell configuration, after cell exposure to 100 microM S-CMC-Lys, a current due to an outward GSH flux was observed, which was inhibitable by 5-nitro-2-(3-phenylpropylamino)-benzoate and glibenclamide. This current was not observed in CFT1-C2 cells, where a functional cystic fibrosis transmembrane conductance regulator (CFTR) is lacking. Inside-out patch-clamp experiments (GSH on the cytoplasm side, Cl(-) on the extracellular side) showed the activity of a channel, which was able to conduct current in both directions: the single channel conductance was 2-4 pS, and the open probability (P(o)) was low and voltage-independent. After preincubation with 100 microM S-CMC-Lys, there was an increase in P(o), in the number of active channels present in each patch, and in the relative permeability to GSH vs Cl(-). Outwardly directed efflux of GSH could also be increased by protein kinase A, adenosine 5'-triphosphate, and cyclic adenosine monophosphate (cAMP) added to the cytoplasmic side (whole-cell configuration). The increased secretion of GSH observed in the presence of S-CMC-Lys or 8-bromoadenosine-3',5'-cyclic monophosphate was also confirmed by HPLC assay of GSH on a confluent monolayer of respiratory cells. Western blot analysis confirmed the presence of CFTR in WI-26VA4 cells. This study suggests that S-CMC-Lys is able to stimulate a channel-mediated GSH secretion by human respiratory cells: electrophysiological and pharmacological characteristics of this channel are similar to those of the CFTR channel.

Carbocysteine↗
PubMed2005

[Treatment of venous thromboembolic disease].

Adequate initial anticoagulant treatment is required to prevent thrombus growth and recurrence. Intravenous unfractionated heparin is being replaced by low-molecular-weight heparin as the anticoagulant of choice for initial treatment of venous thromboembolism. Vitamin K antagonists remain the only oral anticoagulant available (target international normalized ratio: 2.5). The duration of therapy should be individualized according to the risk of recurrence and the risk of bleeding. Three months of treatment is usually adequate if thrombosis was provoked by a reversible risk factor such as surgery. For patients with unprovoked ("idiopathic") thrombosis, anticoagulant treatment for at least 6 months is indicated. For patients with a recurrence of venous thromboembolism or with an irreversible risk factor such as cancer, indefinite anticoagulant therapy is recommended. Long-term treatment with low-molecular-weight heparin is usually preferable for patients with active cancer. Systemic thrombolysis is indicated for patients with massive pulmonary embolism but controversy persists for those with isolated right ventricular dysfunction.

Anticoagulants↗
PubMed2005

Techniques and results of laparoscopic antireflux surgery in Germany.

BACKGROUND: This study aimed to evaluate the development and outcomes of laparoscopic antireflux surgery in Germany using a nationwide representative survey. METHODS: A written questionnaire including 34 detailed questions and 288 structured items about diagnostic and therapeutic approaches, number of procedures, complications, and mortality was sent to 546 randomly selected German surgeons (33% of the registered general surgeons) at the end of 2000. RESULTS: The response rate was 72%, and a total of 2,540 antireflux procedures were reported. According to the survey, 81% of all procedures were performed laparoscopically, and 0.1% were performed thoracoscopically. As reported, 65% were total fundoplications, 31% were partial fundoplications, and 4% were other procedures. Of the surgeons who had experience with laparoscopic antireflux techniques (29%), 71% preferred a 5-trocar technique, and 91% used the Harmonic Scalpel for dissection. There were significant technical variations among the surgical procedures (e.g., use and size of the bougie, length of the wrap, additional gastropexy, fixation of the wrap). The overall complication rate for laparoscopic fundoplication was 7.7% (5.7% surgical and 2% nonsurgical complications), including rates of 0.6% for esophageal perforations and 0.6% for splenic lesions. The conversion rate was 2.9%; the reoperation rate was 1.6%; and the overall hospital mortality rate was 0.13%. The authors observed a striking learning curve difference in complication rates between hospitals performing fewer than 10 laparoscopic antireflux techniques annually and those performing more than 10 fundoplications per year (14% vs 5.1%, p < 0.001). Long-term dysphagia and interventions occasioned by dysphagia occurred significantly more often after total fundoplications than after partial fundoplications (6.6% vs 2.4%; p < 0.001). Similar findings were reported for Nissen versus floppy Nissen procedures. The overall failure rate, however, was similar for both groups (Nissen 8.7%; partial 9%, difference not significant). CONCLUSIONS: Until now, no unique laparoscopic antireflux technique has been accepted, and a number of different antireflux procedures with numerous modifications have been reported. The morbidity and mortality rates reported in this article compare very well with those in the literature, and 1-year-follow-up results are promising.

Gastroesophageal Reflux↗
PubMed2005

Zero-field incommensurate spin-Peierls phase with interchain frustration in TiOCl.

We report on the magnetic, thermodynamic, and optical properties of the quasi-one-dimensional quantum antiferromagnets TiOCl and TiOBr, which have been discussed as spin-Peierls compounds. The observed deviations from canonical spin-Peierls behavior, e.g., the existence of two distinct phase transitions, have been attributed previously to strong orbital fluctuations. This can be ruled out by our optical data of the orbital excitations. We show that the frustration of the interchain interactions in the bilayer structure gives rise to incommensurate order with a subsequent lock-in transition to a commensurate dimerized state. In this way, a single driving force, the spin-Peierls mechanism, induces two separate transitions.

Journal Article↗