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T Meyer

Publications and source records attributed to T Meyer.

At least 19 recordsLinked to original sources
PubMed2007

[Modern diagnosis of Chlamydia trachomatis infections].

Chlamydia trachomatis is the most frequent sexually transmitted bacterial infection. Tests to diagnose C. trachomatis infections include growth on cell culture and assays detecting bacterial antigens or nucleic acids. Until recently, culture was considered the gold standard of testing because of its high specificity. However, the sensitivity of culture is limited. Nucleic acid amplification tests (NATs) have the highest sensitivity and are almost as specific as culture. They are best suited for screening. Chlamydial antigen EIAs are considerably less sensitive and specific, resulting in low positive predictive values, especially when low-prevalence populations are studied. Thus, positive results of chlamydia antigen EIAs should be confirmed by another test.

Bacterial Typing Techniques↗
PubMed2007

Effectiveness of low-intensity endurance training.

Recent studies point to the preventive efficacy of low-intensity endurance training in terms of cardiovascular risk factor modification and mortality reduction. In addition, it is frequently recommended as a means of stimulating fat metabolism. It was the intention of this study to clarify if endurance training effectiveness remains unimpaired when exercise intensity is reduced by a certain amount from "moderate" to "low", but total energy expenditure held constant. For this purpose, 39 healthy untrained subjects (44 +/- 7 yrs, 82 +/- 19 kg; 173 +/- 9 cm) were stratified for endurance capacity and sex and randomly assigned to 3 groups: "moderate intensity" (MOD, n = 13, 5 sessions per week, 30 min each, intensity 90 % of the anaerobic threshold [baseline lactate + 1.5 mmol/l]), "low intensity" (LOW, n = 13, 5 sessions per week, intensity 15 bpm below MOD, duration proportionally longer to arrive at the same total energy output as MOD), and control (CO, n = 13, no training). Training was conducted over 12 weeks and each session monitored by means of portable heart rate (HR) recorders. Identical treadmill protocols prior to and after the training program served for exercise prescription and documentation of endurance effects. VO (2max) improved similarly in both training groups (MOD + 1.5 ml x min (-1) x kg (-1); LOW + 1.7 ml x min (-1) x kg (-1); p = 0.97 between groups). Compared with CO (- 1.0 ml x min (-1) x kg (-1)) this effect was significant for LOW (p < 0.01) whereas there was only a tendency for MOD (p = 0.07). However, objective criteria (HR (max), maximal blood lactate) indicated that a different degree of effort was responsible for this finding. In comparison with CO (mean decrease of 3 bpm), average HR during incremental exercise decreased significantly by 9 bpm (MOD, p < 0.05 vs. CO) and 6 bpm (LOW, p = 0.26), respectively. However, there was no significant difference between MOD and LOW (p = 0.60), but for changes in oxygen uptake at the anaerobic threshold (VO (2AT)) it was observed that MOD was significantly more effective than CO (p = 0.048) and LOW (p = 0.04). It is concluded that within a middle-aged population of healthy untrained subjects, endurance training effectiveness might be slightly impaired when the training heart rate is chosen 15 bpm lower as compared to moderate intensity, but the total energy output held equal.

Adult↗
PubMed2006

Dynamic light scattering study of biaxial ordering in a thermotropic liquid crystal.

Dynamic light scattering from orientational order fluctuations in a liquid crystalline tetrapode reveals successive, weakly first-order isotropic to uniaxial and uniaxial to biaxial nematic phase transitions. The order parameter relaxation rates exhibit temperature dependences consistent with Landau-de Gennes mean field theory. Combined with previous evidence of a second-order uniaxial-biaxial transition in a closely related tetrapode, the present study supports the existence of a nematic-nematic tricritical point in thermotropic liquid crystals.

Journal Article↗
PubMed2006

Histological response of peritoneal carcinomatosis after hyperthermic intraperitoneal chemoperfusion (HIPEC) in experimental investigations.

BACKGROUND: In selected patients with peritoneal carcinomatosis from colorectal cancer prognosis can be improved by hyperthermic intraperitoneal chemotherapy (HIPEC) after cytoreductive surgery. The aim of this study was to evaluate the tumor response of peritoneal carcinomatosis in tumor-bearing rats treated with HIPEC. METHODS: CC531 colon carcinoma (2,5 x 106 cells), implanted intraperitoneally in Wag/Rija rats, was treated by hyperthermic intraperitoneal chemotherapy. After 10 days of tumor growth the animals were randomized into five groups of six animals each: group I: control (n = 6), group II: sham operated animals (n = 6), group III: hyperthermic intraperitoneal perfusion (HIP) without cytostatic drugs, group IV: HIPEC with mitomycin C in a concentration of 15 mg/m2 (n = 6), group V: mitomycin C i.p. alone in a concentration of 10 mg/m2 (n = 6). After 10 days the extent of tumor spread and histological outcome were analysed by autopsy. RESULTS: All control animals developed extensive intraperitoneal tumor growth. Histological tumor load was significantly reduced in group III and group V and was lowest in group IV. In group II tumor load was significantly higher than in group I. Implanted metastases were significantly decreased in group IV compared with group I and group II. CONCLUSION: These findings indicate that HIPEC is an effective treatment for peritoneal carcinomatosis in this animal model. HIPEC reduced macroscopic and microscopic intraperitoneal tumor spread.

Adenocarcinoma↗
PubMed2006

Investigations on safety of hyperthermic intraoperative intraperitoneal chemotherapy (HIPEC) with Mitomycin C.

AIMS: Previous safety monitoring of hyperthermic intraoperative intraperitoneal chemotherapy (HIPEC) with Mitomycin C (MMC) did not demonstrate any detectable safety hazard to the personnel. Nevertheless, those results have been discussed controversially because of the methodological problems employed in the evaluation of potential exposure. We re-evaluated possible safety hazards of HIPEC by applying different monitoring strategies. METHODS: We monitored air samples in the operation room during HIPEC. In addition, we measured MMC in plasma of the surgeon with a newly developed analytical method. All samples were analysed by HPLC-UV at 360nm. The permeability of the gloves was tested using two in vitro techniques: diffusion cells and a glass cell chamber. In-use and worst-case exposure scenarios were imitated for in vitro experiments. RESULTS: The analysis of the air samples (n=3) could not detect any MMC. We found no drug above the limit of detection (1microg MMC/L) in the plasma samples of the surgeons (n=5). A breakthrough of latex glove material was detected in only one (worst-case exposure scenario) of 40 diffusion cell experiments. CONCLUSIONS: Established methods of safety monitoring could not reveal any detectable risk on in-use exposure conditions. The wearing of doubled latex gloves should prevent the surgeon from dermal exposure to MMC during HIPEC.

Air Pollutants, Occupational↗
PubMed2006

Orientational order and dynamics of the dendritic liquid crystal organo-siloxane tetrapodes determined using dielectric spectroscopy.

The dielectric measurements have been carried out on the two zeroth generation dendrimers with four branched arms (called tetrapodes) based on the siloxane cores. The results are analyzed in the framework of the molecular theory of dielectric permittivity by Maier and Meier for nematogens. At least four molecular processes are resolved in the dielectric relaxation spectra in the nematic phase for each of the two tetrapodes. Three of them are assigned to the reorientation of the monomeric unit whereas the fourth is assigned to the rotation of the molecular segments in the individual arms of the monomeric unit around the long molecular axis. The dielectric relaxation strength of the low frequency process has been used to calculate the orientational order parameter. The dynamics of the resolved processes has been quantitatively analyzed using the results of the microscopic model of the rotational diffusion, given by Coffey and Kalmykov [W. T. Coffey and Yu. P. Kalmykov, Adv. Chem. Phys. 113, 487 (2000)] using the calculated order parameter. All molecular processes: the rotation around the short molecular axis (end-over-end rotation), precession around the director and the rotation around the long molecular axis (also called the spinning motion) are shown to have successfully been reproduced by the model. The anisotropy of the rotational diffusion coefficients gradually increases with a reduction in temperature, to a factor of 3 in the nematic phase relative to its isotropic phase.

Journal Article↗
PubMed2006

Bicuspid aortic valve: evaluation of the ability to participate in competitive sports: case reports of two soccer players.

UNLABELLED: Two competitive soccer players aged 23 and 17 years with known bicuspid aortic valve presented for sports-medical pre-participation screening. Both athletes were well trained and had a maximal oxygen uptake of 61 and 60 ml/min/kg, respectively. Echocardiography of the first athlete revealed an eccentric hypertrophy of the left ventricle (end-diastolic diameter 58-59 mm, septal and posterior myocardial wall thickness 12-13 mm) with good systolic and diastolic function and a functional bicuspid aortic valve with mild regurgitation. In the second athlete, echocardiography showed a bicuspid aortic valve with moderate regurgitation and a relative stenosis, a hypertrophied left ventricle (end-diastolic diameter 62-63 mm, myocardial wall thickness 13-16 mm) and dilation of the ascending aorta of 46 mm, which was confirmed by magnetic resonance imaging. According to international guidelines, the first athlete was allowed to participate in competitive soccer. Nevertheless, regular cardiologic examinations in intervals of 6 months were recommended. In the second case, the athlete was not allowed to take part in competitive sports due to the extended ecstasy of the ascending aorta and the concomitant risk of an aortic rupture. In addition, the left ventricular hypertrophy has to be considered as pathologic. Therefore, the athlete was only allowed to exercise in recreational sports with low and easily controllable intensities. CONCLUSION: In athletes with bicuspid aortic valve, besides the evaluation of the aortic valve, physiologic adaptations of the heart have to be differentiated from pathological changes. Furthermore, the aorta deserves special attention, because in the case of a (probably genetically determined) dilated ascending aorta, an elevated risk for aortic rupture is present during intensive and competitive exercise. A general judgement in athletes with bicuspid aortic valves on their ability to participate in competitive sports is, therefore, not possible.

Adolescent↗
PubMed2006

Characteristics of inline speedskating--incremental tests and effect of drafting.

Competitive inline speedskating combines a movement pattern similar to speedskating on ice with pack-oriented competition modes known from cycling. The deep-seated body position leads to high static load and, thus, restricted blood flow within propulsive muscles. This condition may affect lactate kinetics and limit V.O (2peak). The present study compares physiologic reactions to graded cycling and skating exercise among top-level inline speedskaters and quantifies the effect of drafting. Eight male inline speedskaters of the top national level were examined. The study consisted of two graded exhaustive exercise tests (cycling and speedskating) and a pairwise drafting test. All tests were carried out with simultaneous gas exchange (MetaMax 2, Cortex, Germany) and heart rate measurements as well as determination of blood lactate concentrations. Maximal values of oxygen consumption (cycling: 4.91 +/- 0.60; skating: 4.85 +/- 0.50 l . min (-1); p = 0.78), lactate concentration, or heart rate were similar for cycling and skating. At workloads corresponding to blood lactate concentrations of 4 mmol . l (-1) oxygen uptake (cycling: 3.24 +/- 0.65; skating: 3.97 +/- 0.40 l . min (-1); p < 0.05) and heart rate (cycling: 162 +/- 9; skating: 173 +/- 6 min (-1); p < 0.05) were significantly higher during skating. The differences in heart rate ranged between - 2 and 23 min (-1). The drafting effect was 15 +/- 6 % at 30 km . h (-1) (3.34 +/- 0.19 vs. 2.83 +/- 0.29 l . min (-1)) and 14 +/- 5 % at 33 km . h (-1) (3.87 +/- 0.26 vs. 3.32 +/- 0.27 l . min (-1)). During inline speedskating the attainment of VO2peak is not impaired when compared to cycling exercise. However, the derivation of exercise prescriptions from a stepwise cycling test does not seem appropriate. The drafting effect of inline speedskating is within the range known from cycling.

Adult↗
PubMed2006

[Perianal abscess and anal fistula in infancy and childhood. A congenital etiology?].

BACKGROUND: Perianal abscess and anal fistula in childhood are commonly treated in the same way as abscess and fistula in adults. We questioned whether they represent a cryptoglandular infection, as in adults, or two different diseases with the same symptoms. MATERIALS AND METHODS: We retrospectively analyzed all medical records of 80 children (seven male, 73 female) who underwent surgical treatment for primary perianal abscess or primary anal fistula during a 10-year period. The records were analyzed concerning age at appearance of lesion, sex, diagnosis (fistula and/or abscess), and anatomic localization of the lesion. RESULTS: Of all the children, 67.5% were treated during their 1st year of life and another 10% during their 2nd year (group 1: 77.5%, n=62). Only 22.5% were 3 or older (group 2, n=18). Group 1 contained significantly more male infants (m:f 30:1). However, much more balanced sex distribution was detected in group 2 (m:f 2.6:1), similarly to adults. Analyzing anatomic localization, a second important difference could be found: in contrast to group 2, almost two thirds of all anal fistulas/abscesses in group 1 were localized horizontally between 3:00 and 9:00 o'clock in crown-rump position. CONCLUSIONS: Divergences in preference of age, sex, and localization suggest a congenital etiology for anal fistulas and perianal abscesses in children.

Abscess↗
PubMed2006

Neuropsychological changes in a large sample of liver transplant candidates.

One-hundred forty-eight pre-liver transplant candidates completed a psychological interview and brief neuropsychological testing. Assessment measures included the Repeatable Battery of Neuropsychological Status, Shipley Institute of Living Scale, Trail Making Test Parts A and B (TMT-A and TMT-B), and the Folstein Mini Mental State Exam. Participants in our sample scored in the Below Average range of functioning (mean score = 100; SD = 10) on measures of memory (mean = 89.51, SD = 17.43), attention (mean = 87.62, SD = 17.23), and spatial perception (mean = 88.69, SD = 20.39). Scores reflected moderate to severe impairment in organization and processing speed (TMT-B completion time in seconds: mean = 137.22, SD = 88.64). Controlling for the effects of prior education, MELD scores were strongly correlated with poorer performance on immediate and delayed memory subtests (both P < .01), as well as with diminished attentional capacity (P = .03). MELD scores also were significantly related to slower completion times on the TMT-A and TMT-B (both P < .05). Furthermore, independent sample t tests indicated that patients with higher MELD scores (>10) experienced significantly greater difficulty with executive functioning (P < .05) and delayed memory (P < .05) than those with lower MELD scores. Thorough evaluations of cognitive functioning are needed pretransplant to identify and treat cases of subclinical hepatic encephalopathy before daily functioning becomes significantly impaired.

Attention↗
PubMed2006

[Validity of patient self report data in rehabilitation research: identifying circumstances of the patients' completion of questionnaires].

BACKGROUND: Self-report questionnaires have become wide-spread and are an integral part in different fields of rehabilitation. However, it is still unclear to what extent the validity of the patients' reports is affected by motivational factors. How difficult is it for the patient to fill out questionnaires? What are the situational characteristics in which the patients fill them out? The present study aims to identify the situational, motivational and cognitive requisites of the respondents and to analyse possible impacts on the validity of self-reports. METHOD: A total of n = 105 patients scheduled for inpatient rehabilitation were interviewed by means of a guided open-ended interview in the admission phase. It is a consecutive sample of all admissions in two rehabilitation clinics in Schleswig-Holstein, which provide each patient with a questionnaire to fill out prior to their stay. The analysis involved a description of statements (categories) that have been derived by content analysis based on the patient interviews. In addition, physicians rated various patients' characteristics at the end of their hospital stay. RESULTS: The participation rate of the patients was 95.5 %. Of all patients, 95 % filled out the questionnaires at home, 69 % without a break. 57 % of the patients interviewed had filled out the questionnaires by themselves without any help, another 22 % worked it through together with their partner or spouse. The extent of influence on the responses appeared to be dependent on the amount of help necessary. In a substantial number of patients the questionnaires were regarded as an "official" document that had to be worked through meticulously. Physicians attested 96 % of the patients to have provided honest reports with regard to personal characteristics, and 95 % to have shown a sufficient degree of willingness of self-disclosure. By and large the patients' perceptions of themselves fit with the perceptions the physician in 76 % of the patients from the physicians' point of view. All patients except one were attested a positive motivation to take part in rehabilitation activities in the clinic by the physician. In individual cases there were substantial deficits of cognitive capacities necessary to work through a questionnaire, as well as limitations in literacy. Four patients had insufficient mastery of the German language. DISCUSSION AND CONCLUSION: The vast majority of the patients possessed sufficient motivational and cognitive prerequisites to provide valid self-reports. Patients with problems in responding asked partners or others for help, its impact on the self-reports being as yet not clear-cut. In individual cases it can not be ruled out that patients who think about early retirement provide distorted statements.

Adult↗
PubMed2006

Recurrent laryngeal nerve monitoring during thyroid surgery in childhood.

INTRODUCTION: Diseases of the thyroid gland are one of the most common endocrinopathies in childhood. Neither benign nor malignant thyroid diseases are often treated surgically. But if surgical treatment is carried out, intraoperative damage of the recurrent laryngeal nerve (RLN) is a common and severe complication. In adult surgery, therefore, intraoperative monitoring (IOM) of the RLN is a method which has been used since several years. The question is whether this method can be used in paediatric surgery for the identification and functional control of the integrity of the RLN. METHODS: Surgical treatment of benign (9 x) or malignant (1 x) thyroid diseases was performed in ten children (median age: 13 years) with 16 nerves at risk (NAR). The function of the vocal cord was controlled in all children before and after surgery. Intraoperative identification and functional control of the recurrent nerve was performed using the Neurosign 100, placing a needle electrode transligamentously into the vocal muscle. All results before and after resection were documented. RESULTS: A clear and reliable identification of the RLN was possible in all cases. All NAR showed a constant physiological nerve signal before and after surgical resection of the thyroid gland. However in one young patient the postoperative control of the vocal cord revealed a partial paralysis despite the constant intraoperative signal of the RLN. The control on this patient after a period of six months showed a normal function. CONCLUSION: IOM of the RLN as used in adult surgery could easily be used in paediatric surgery as well. A clear and positive identification of the RLN was possible in all these patients. Therefore, IOM of the RLN could develop into a helpful and easy method for the prevention of intraoperative damage of the recurrent laryngeal nerve during thyroid surgery in childhood.

Adolescent↗
PubMed2006

The advantages and disadvantages of nerve monitoring during thyroid surgery in childhood.

BACKGROUND: Intraoperative damage of the recurrent laryngeal nerve (RLN) and the external branch of the superior laryngeal nerve (EBSLN) are common and cause complications in thyroid surgery. The method of intraoperative electrophysiological neuromonitoring (IONM) of the RLN and the EBSLN has been used in adults for several years. The question is whether IONM can be used in paediatric surgery for the identification and functional control of the RLN and the EBSLN, and what the advantages and disadvantages of using it are. METHODS: Surgical treatment of benign (n = 9) and malign (n = 2) thyroid diseases was carried out in eleven children (median age: 13 years) with a total of 18 nerves at risk (NAR). The function of the vocal cord was monitored in all children before and after surgery. Intraoperative identification and functional control of RLN and EBSLN was performed using the Neurosign 100. All results before and after resection of the thyroid gland were documented. RESULTS: A clear and reliable identification of the RLN and the EBSLN was possible in all cases. All NAR showed a constant physiological nerve signal before and after surgical resection of the thyroid gland. However, in one young patient the postoperative examination of the vocal cord revealed a partial paralysis on the left side after thyroidectomy, despite the constant intraoperative signal of the RLN. After a period of six months, normal functioning had resumed. CONCLUSION: The IONM of both RLN and EBSLN in adult surgery could be used successfully in paediatric surgery. In this study a clear and positive identification of both nerves was possible in all patients. Therefore the IONM of the RLN and EBSLN could develop into a successful and easy method for the prevention of intraoperative nerve damage during thyroid surgery in childhood and young adolescence. Assuming that a constant IONM signal represents a normal vocal cord, our evaluation showed that there is a small percentage of false negative and positive results.

Adolescent↗
PubMed2006

[Predicting gainful employment in a population sample of 4225 statutory pension insurance members covering a prognostic period of five years using a brief subjective prognostic employment scale (SPE Scale)].

PURPOSE: Vocational (dis-)ability is a key concept in social medicine. It plays a major role in the realm of statutory pension funds (e. g. appraisal of applications for early retirement) as well as in epidemiologic or rehabilitation research. In a former population-based survey reliability of a short scale assessing the subjective prognosis of gainful employment (SPE-Scale, range = 0 - 3) had been tested. We now wanted to explore whether the SPE-Scale allows a prediction of vocational outcomes (early retirement) in the population sample over longer periods of time. METHODS: Statutory pension insurees from Luebeck and surroundings aged between 40 and 55 were surveyed by questionnaire in 1999/2000. For 4225 subjects (= 95% of the original cohort) we obtained the following outcome data from pension fund records: dates of any applications for early retirement and beginning of retirement, date of death. The follow-up period covers 4.75 years on average. During this period 323 applications for early retirement (= 7.6%) were filed, and 200 subjects (= 4.7%) actually retired. RESULTS: First analysis including age and sex as covariates showed a threefold (SPE = 2) and eightfold (SPE = 3) risk of early retirement. Multivariate analysis (covariates: overall health status, number of chronic conditions, approved disability, subjective vocational ability, and length of sick leave measured at study onset) yielded a twofold risk of filing an application for early retirement (SPE = 3). CONCLUSIONS: The SPE-Scale is an appropriate screening instrument for hazards regarding gainful employment. It also can be recommended for use in epidemiologic or rehabilitation surveys.

Adult↗
PubMed2006

[Comparison of unspecific bronchial provocation during controlled and spontaneous inhalation].

Using controlled breathing patterns during inhalation of drugs is characterized by a high dose reproducibility which may be of advantage for bronchial provocation testing. In this study 30 healthy subjects with an anamnesis of atopy underwent in a randomized cross-over design bronchial provocation testing with methacholine either with the Viasys-Jäger-APS system or with controlled inhalations (AKITA-System) (controlled inhalation volume and flow). Measured was the frequency of positive test results. Positive test results were defined by a 20 % decline of FEV (1) or a 100 % increase of specific airway resistance (sRaw). There were no significant differences in the prevalence of positive test results obtained with both techniques: APS-FEV (1) : 8, AKITA-FEV (1) : 9; APS-sRaw: 18, AKITA-sRaw: 17. More subjects showed a 100 % increase of sRaw as compared to a 20 % decrease of FEV (1), which may be interesting in order to understand differences in the diagnostic information given by both parameters. However, there were some discrepancies: only in 25 of 30 cases (sRaw: 21 of 30 cases) the results (positive or negative) agreed between both techniques. Although the two techniques for bronchial provocation test showed some discrepancies, these data suggest that controlled inhalations may be an alternative to the APS-system.

Bronchial Provocation Tests↗
PubMed2006

Successful treatment of multiple actinic keratoses in organ transplant patients with topical 5% imiquimod: a report of six cases.

BACKGROUND: Nonmelanoma skin cancer represents a significant cause of morbidity in organ transplant recipients (OTRs). Cutaneous malignancies, mainly invasive squamous cell carcinoma and its precursor actinic keratosis (AK), appear approximately 5-10 years after organ transplantation. Impaired wound healing and high recurrence rates in immunocompromised patients treated with destructive therapies such as cryosurgery or topical 5-fluorouracil represent frequently known complications. OBJECTIVES: To evaluate the safety and efficacy of imiqimod 5% in the treatment of AKs in OTRs. METHODS: Six OTRs (two kidney, two heart, one lung and one liver) with extensive AKs were treated with imiquimod 5% cream two to three times weekly in an open-label uncontrolled, nonrandomized pilot study. RESULTS: In five of six patients treated with imiquimod 5% cream all AK lesions were cleared after 12-16 weeks. One patient showed partial response. Local adverse events at the site of application included erythema, oedema and mild erosion. No wound infection or scarring was observed in any of these patients. All graft-related laboratory parameters were stable during and after treatment. Immunosuppressive therapy remained unchanged throughout the treatment. CONCLUSIONS: These results suggest that imiquimod 5% cream may be useful for the local treatment of precancerous AK lesions in OTRs.

Administration, Cutaneous↗