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T Kühn

Publications and source records attributed to T Kühn.

At least 19 recordsLinked to original sources
PubMed2005

Contamination of the alluvial plain, feeding-stuffs and foodstuffs with polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans (PCDD/Fs), dioxin-like polychlorinated biphenyls (DL-PCBs) and mercury from the River Elbe in the light of the flood event in August 2002.

Meadow soils, feeding-stuffs and foodstuffs from the alluvial plain of the river Elbe were analyzed in respect of PCDD/Fs, DL-PCBs and mercury with a view to assessing the consequences of the extreme flood of August 2002. The PCDD/F concentrations in the soils range from 3 to 2100 ng WHO-TEQ/kg dm, and for the DL-PCBs the range was 0.32 to 28 ng WHO-TEQ/kg dm. On the basis of established threshold values >40% of the areas are only fit for restricted usage. Mercury concentrations range from 0.11 to 17 mg/kg dm, whereby the action value of 2 mg/kg dm is exceeded in about 50% of the soil samples. A cumulative memory effect from past floods rather than a recent contamination from August 2002 is documented. Soils taken from behind broken dykes showed significantly lower concentrations. Grass, hay and grass silage originating from pasture land in Lower Saxony were taken before and immediately after the flooding. PCDD/Fs range from 0.29 to 16 ng WHO-TEQ/kg, the maximum permitted value of 0.75 ng WHO-TEQ/kg was exceeded in about 50% of the samples. Muscle-tissue from cattle, sheep, lamb and a roe deer as well as untreated milk from individual cows returned values ranging from 0.76 to 5.9 pg WHO-PCDD/F-TEQ/g fat, and 10% of the samples returned values higher than the permitted maximum of 3 pg WHO-PCDD/F-TEQ/g fat. The action value of 2 pg WHO-PCDD/F-TEQ/g fat was exceeded in 33% of the samples. No direct connection between these results and the effects of the flood could be established. A major input path for PCDD/Fs is the tributary Mulde, which discharges contaminated sediments from its catchment area into the Elbe.

Animal Feed↗
PubMed2004

[Chronic musculoskeletal pain--aspects for assessment in private disability compensation (I)].

Pain is the most frequent symptom of diseases of the musculoskeletal system. Moreover pain is the most frequent complaint in applications for governmental or private disability compensation. Since pain remains a subjective sensory perception, it is the task of assessment to prove all the proband's information for consistency. Both multidimensionality of chronic pain and a high impact of psychosomatic comorbidity imply that not only orthopaedic and traumatologic but as well psychosomatic competence for legal assessment is required.

Chronic Disease↗
PubMed2004

Subcellular vesicular aggregations of GABAB R1a and R1b receptors increase with age in neurons of the developing mouse brain.

GABA(B) receptors play a critical neuromodulatory role in the central nervous system. It has been suggested that both the functional role and the cellular distribution of GABA(B) receptors in the neuronal network change during post-natal maturation. In the present study, the cellular and subcellular distribution patterns of the GABA(B) R1a/b receptors have been analysed in different brain regions of the mouse using immunocytochemistry with isoform-specific antisera. GABA(B) R1-immunoreactivity (IR) was present from the first post-natal day (P0) on in most regions of the brain. Neurones exhibited diffuse GABA(B) R1-IR labelling throughout somata and larger proximal dendrites as well as some fine neuronal processes. After P5, distinct punctuated staining was apparent. The number of such GABA(B) IR granules per cell increased with age in a sigmoidal manner from P5 to P60. Electron microscopy revealed GABA(B) IR as clusters of small clear vesicles of 30-50 nm diameter within the cytoplasm and close to the cell membrane at extrasynaptic locations, as well as at pre-synaptic and post-synaptic specialisations. The increase in GABA(B) R1-IR punctuate staining during brain maturation points to increasing functional participation and heterogeneity of GABA(B) receptors as the complexity of the central nervous system expands with growth and development.

Aging↗
PubMed2004

[Sentinel node biopsy in breast cancer].

The international consensus conference from St. Gallen concerning the treatment of early breast cancer concluded in 2003, that sentinel node biopsy was now accepted as method allowing axillary staging in breast cancer. This procedure may avoid complete lymph node dissection in appropriate cases. Since numerous questions associated with the technique are still not defined and the procedure itself is not yet standardized, the German Society of Senology defined the conditions for the routine clinical use of sentinel node biopsy in an interdisciplinary consensus meeting.

Breast Neoplasms↗
PubMed2002

Breast MRI for monitoring response of primary breast cancer to neo-adjuvant chemotherapy.

The objective of the present study was to monitor response to preoperative chemotherapy with breast MRI in patients with large breast cancer. Fifty-eight women in whom core biopsy had confirmed the presence of breast carcinoma underwent breast MRI prior to beginning chemotherapy and before surgical excision. In 24 cases patients underwent one or two additional examinations during chemotherapy to monitor their progress. Breast MRI included both T2-weighted spin-echo sequences and T1-weighted gradient-echo sequences before and 1, 2, 3, and 8 min after bolus injection of gadolinium-DTPA. Tumor size and the dynamic contrast medium uptake patterns of the respective carcinomas were evaluated and compared with the final histology findings. Based on their MR tomographic findings (change in tumor size and intensity of contrast media uptake), patients were assigned to groups with non-response (NR), partial response (PR), and complete response (CR). Based on MR tomographic findings, there were 12 patients in the NR group, 34 in the PR group, and 12 in the CR group. In NR group contrast medium uptake tended to increase or show no more than minimal decrease. Diagnostic accuracy for assigning patients to the NR group was 83.3% and to the PR group 82.4%. In patients whose tumors showed only slight response to chemotherapy, breast MRI proved very reliable in determining the size of the lesions. In patients whose tumors displayed significant response and in the CR group, the size of the residual tumor was underestimated in 8 of 12 cases. In 66.7% of patients in the CR group histology revealed residual tumor masses in areas up to 5 cm in diameter. During chemotherapy, intensity of contrast medium uptake decreased in 88.2% of patients with PR and in all patients with CR. Reliable determination of response was possible within 6 weeks following the initiation of chemotherapy. Breast MRI is suitable as a monitoring method. The determination of residual tumor size is unreliable in carcinomas exhibiting significant response to chemotherapy which may lead to false-negative results. The method may be employed for monitoring response to chemotherapy after 6 weeks.

Adult↗
PubMed2001

Fluorine-18 2-deoxy-2-fluoro-D-glucose PET in the preoperative staging of breast cancer: comparison with the standard staging procedures.

The present study compared the diagnostic accuracy of fluorine-18 2-deoxy-2-fluoro-D-glucose positron emission tomography (FDG-PET) with conventional staging techniques. The differentiation between malignant and benign lesions and the detection of multifocal disease, axillary and internal lymph node involvement, and distant metastases were evaluated. One hundred and seventeen female patients were prospectively examined using FDG-PET and conventional staging methods such as chest X-ray, ultrasonography of the breast and liver, mammography and bone scintigraphy. All patients were examined on a modern full-ring PET scanner. Histopathological analysis of resected specimens was employed as the reference method. The readers of FDG-PET were blinded to the results of the other imaging methods and to the site of the breast tumour. The sensitivity and specificity of FDG-PET in detecting malignant breast lesions were 93% and 75% respectively. FDG-PET was twofold more sensitive (sensitivity 63%, specificity 95%) in detecting multifocal lesions than the combination of mammography and ultrasonography (sensitivity 32%, specificity 93%). Sensitivity and specificity of FDG-PET in detecting axillary lymph node metastases were 79% and 92% (41% and 96% for clinical evaluation). FDG-PET correctly indicated distant metastases in seven patients. False-positive or false-negative findings were not encountered with FDG-PET. Chest X-ray was false-negative in three of five patients with lung metastases. Bone scintigraphy was false-positive in four patients. Three patients were upstaged since FDG-PET detected distant metastases missed with the standard staging procedure. It is concluded that, compared with the imaging methods currently employed for initial staging, FDG-PET is as accurate in interpreting the primary tumour and more accurate in screening for lymph node metastases and distant metastases. Due to a false-negative rate of 20% in detecting axillary lymph node metastases, FDG-PET cannot replace histological evaluation of axillary status.

Adult↗
PubMed2001

Impact of the axillary nodal status on sentinel node mapping in breast cancer and its relevance for technical proceeding.

OBJECTIVE: The aim of this study is to analyze whether the axillary status influences the lymphatic mapping procedure in malignant breast disease and whether clinically relevant consequences for the technique of Sentinel Node (SN) biopsy may be drawn from this information. MATERIALS AND METHODS: SN biopsy was performed in 150 consecutive patients using a combination of the radioguided and the blue-dye technique. Axillary status was compared with the number of detected nodes. In cases of numerous nodes with tracer uptake, the radioactivity of each radiolabeled node was measured separately in a dose calibrator. We analyzed whether an increased tracer uptake could possibly indicate a 'true' or 'dominant' SN. Blue dye uptake was registered and compared with radioactivity. The findings were related to the histologic results. RESULTS: In patients with a positive axillary status, significantly more radiolabeled nodes were detected than in node negative patients (median 3 vs. 2; p < 0.001). In 54/86 patients with numerous SNs a 'dominant' node with at least twice the radioactivity than other marked nodes could be identified (62.8%). From 26 cases with axillary involvement, 20 patients (76.9%) were identified by the 'dominant' and the remaining six women (23.1%) by others than the seemingly leading SN. CONCLUSION: Axillary lymph node involvement influences the drainage pattern in breast cancer. Patients with numerous SNs have an increased risk of axillary involvement. A high tracer uptake does not permit the identification of a 'true' SN. A lack of surgical accuracy may lead to pitfalls if the axilla is not screened carefully for all radioactive nodes.

Adult↗
PubMed2000

[Work disability: malignant tumors as markers of noticeable risk in occupational groups].

A risk adequate premium development of private disability insurance requires a correct valuation of the disability probability. If the reasons for disability are known, especially the share of cancer, the development of damage within a job class can be anticipated. For this a relatively small collective is enough. The new findings should be substantiated as far as possible by further analysis and can be the basis for the evaluation of disability probabilities of job classes within the business in force.

Adult↗
PubMed2000

Axilloscopy and endoscopic sentinel node detection in breast cancer patients.

BACKGROUND: Sentinel node biopsy is a promising technique that allows the axillary status of breast cancer patients to be predicted with high accuracy. Reducing false negative results remains a major challenge for the improvement of this procedure. Furthermore, new techniques are required to achieve axillary clearing with less morbidity in cases of unsuccessful mapping or multicentric carcinoma. We analyzed whether axilloscopy and endoscopic sentinel node biopsy is a feasible procedure for visualization of the axillary space and resection of the sentinel node using endoscopic techniques. METHODS: Following blue dye-guided lymphography and liposuction of the axillary fat, endoscopic axillary sentinel node biopsy was performed in 35 breast cancer patients. We then assessed the exposure of anatomical landmarks, the detection rate of the sentinel node, the false negative rate, and the accuracy of consecutive axillary clearing. RESULTS: In almost every case, an excellent anatomical orientation was achieved. The detection rate for the sentinel node was 83.3%. In one case, the sentinel node did not reflect the status of the residual axilla. A mean number of 17.1 lymph nodes was harvested at consecutive axillary clearing. CONCLUSIONS: Axilloscopy and endoscopic sentinel node biopsy, following liposuction of the axillary fat, is a feasible procedure that allows identification and minimally invasive resection of the sentinel node with high accuracy. The endoscopic approach might help to minimize the pitfalls of sentinel node biopsy by visualizing the axillary space. In future, it may become a technique that enables minimally invasive axillary clearing when complete lymphadenectomy is required.

Adult↗
PubMed2000

In vivo spectroscopy in dermatology: methods and new fields of application.

BACKGROUND: The human skin is an easily accessible organ on which non-invasive examination methods can be applied. Remittance spectroscopy uses registration of the proportion of reflected light from the skin surface. Optical characteristics of skin are determined by scattering, reflection and absorption. The remittance is influenced by various test conditions and topography. Spectroscopic methods are applied for determination of microcirculation, measuring of erythema and pigmentation and in pharmacology and toxicology of applied drugs. CONCLUSION: The standardization of spectroscopic measurement of human skin is essential to reduce error sources. In future a better investigation of skin structures and molecules, which are responsible for optical characteristics of skin and a more precise evaluation of spectroscopic signals are necessary to get more information about the state of skin and to develop new fields of applications, such as early diagnosis of skin diseases or monitoring of metabolic processes.

Erythema↗
PubMed2000

[Laparoscopic intraoperative differential diagnosis of adnexal tumors. A pilot study of 20 premenopausal patients].

AIM: The purpose of the study was to determine the feasibility and potential clinical value of laparoscopic intraoperative sonography in the female genital tract. PATIENTS AND METHOD: Intraoperative ultrasound was performed in 20 consecutive premenopausal patients with adnexal masses during laparoscopy using a 7.5 MHz semiflexible transducer. RESULTS: Laparoscopic ultrasound of the female genital tract improves image resolution. Furthermore, this new method allows accurate localisation of early tubal pregnancy and may be helpful if laparoscopic evaluation of the inner genital tract is impaired by severe adhesions. In 7 out of 20 patients, the therapeutical procedure was clearly influenced by the laparoscopic ultrasound findings, resulting in a benefit for the patients in all seven cases. CONCLUSION: Intraoperative laparoscopic ultrasound may improve minimal invasive management of adnexal masses.

Adnexal Diseases↗
PubMed1999

Early detection and accurate description of extent of metastatic bone disease in breast cancer with fluoride ion and positron emission tomography.

PURPOSE: Previous studies have shown that bone metastases are revealed by magnetic resonance imaging (MRI) or bone marrow scintigraphy several months before they are visible by conventional bone scintigraphy (BS). We present a new approach for detecting bone metastases in patients with breast cancer. We compared findings obtained with fluoride ion (F-18) and positron emission tomography (PET) with those obtained with conventional BS. PATIENTS AND METHODS: Thirty-four breast cancer patients were prospectively examined using F-18-PET and conventional BS. F-18-PET and BS were performed within 3 weeks of each other. Metastatic bone disease was previously known to be present in six patients and was suspected (bone pain or increasing levels of tumor markers, Ca(2+), alkaline phosphatase) in 28 patients. Both imaging modalities were compared by patient-by-patient analysis and lesion-by-lesion analysis, using a five-point scale for receiver operating characteristic (ROC) curve analysis. A panel of reference methods was used, including MRI (28 patients), planar x-ray (17 patients), and spiral computed tomography (four patients). RESULTS: With F-18-PET, 64 bone metastases were detected in 17 patients. Only 29 metastases were detected in 11 patients with BS. As a result of F-18-PET imaging, clinical management was changed in four patients (11.7%). For F-18-PET, the area under the ROC curve was 0.99 on a lesion basis (for BS, it was 0.74; P <.05) and 1.00 on a patient basis (for BS, it was 0.82; P <.05). CONCLUSION: F-18-PET demonstrates a very early bone reaction when small bone marrow metastases are present, allowing accurate detection of breast cancer bone metastases. This accurate detection has a significant effect on clinical management, compared with the effect on management brought about by detection with conventional BS.

Adult↗
PubMed1999

[Endoscopic axillary lymph node excision--results of a pilot study].

OBJECTIVE: Assessment of axillary nodal status with reduced shoulder-arm-morbidity remains a major challenge for primary surgery of breast cancer patients. In a pilot study endoscopic axillary lymph node dissection was evaluated. MATERIAL AND METHODS: In 30 breast cancer patients axillary lymphadenectomy was performed after liposuction using an endoscopic approach. During a learning phase of 15 cases an open revision was routinely carried out. Later complete endoscopic lymph node dissection was performed. The exposition of anatomical landmarks, the number of resected lymph nodes, postoperative lymphorrhea, histopathological signs of traumatisation were assessed as well as intra and postoperative complications. RESULTS: In any case we found excellent exposure of anatomical landmarks. Following a learning curve of 15 cases the average number of resected lymph nodes was equal to the average number of lymph nodes resected with conventional techniques (18.2 vs. 18.4, median 17 vs 18). Minimal intraoperative complications were observed. Postoperative lymphorrhea and seroma rate were not remarkably reduced in comparison with open procedures. CONCLUSIONS: Our study demonstrates, that endoscopic lymph node dissection may be performed with a low complication rate and with identical accuracy as achieved by open techniques.

Axilla↗
PubMed1995

[Endoscopic therapy of adnexa tumors using endobag extraction].

Evidence of 39 treated cases of cystic adnexal tumours of unclarified quality indicates that laparoscopic resection with subsequent extraction of the entire tumour in an endobag could provide the possibility of an endoscopic operation even in cases of indistinct tumours or of patients with enhanced perioperative risks. In particular patients with increased morbidity due to immobilisation might especially benefit from the technique.

Adult↗