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Biomedical subjects

C Trautmann

Publications and source records attributed to C Trautmann.

At least 19 recordsLinked to original sources
PubMed2006

3D tissue culture substrates produced by microthermoforming of pre-processed polymer films.

We describe a new technology based on thermoforming as a microfabrication process. It significantly enhances the tailoring of polymers for three dimensional tissue engineering purposes since for the first time highly resolved surface and bulk modifications prior to a microstructuring process can be realised. In contrast to typical micro moulding techniques, the melting phase is avoided and thus allows the forming of pre-processed polymer films. The polymer is formed in a thermoelastic state without loss of material coherence. Therefore, previously generated modifications can be preserved. To prove the feasibility of our newly developed technique, so called SMART = Substrate Modification And Replication by Thermoforming, polymer films treated by various polymer modification methods, like UV-based patterned films, and films modified by the bombardment with energetic heavy ions, were post-processed by microthermoforming. The preservation of locally applied specific surface and bulk features was demonstrated e.g. by the selective adhesion of cells to patterned microcavity walls.

Animals↗
PubMed2005

[Background concentrations of molds in house dust. Determination of mold concentrations in dwellings without known mold infestations in three parts of Germany].

Mold concentrations of house dust samples from dwellings reportedly free from mold infestations were analysed to obtain background values. Samples from carpet floors were taken from 80 dwellings in three parts of Germany in winter and summer. Samples were analysed with the cultivation method (using suspension). This resulted in the detection of 35 mold species or genera. Concentrations of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summer. In contrast concentrations of Aspergillus and Penicillium in the summer samples were nearly equal to those in the winter samples. The majority of the various molds were only found in a number of samples too small for a reliable comparison of the winter and summer findings to be made. The results were compared with findings of other authors. The authors propose the concentrations of the 95th percentile of each species (when representing over 10,000 KBE/g of dust) as background values, while a threefold higher value is regarded as an indication of mold presence. An exception should be made for the concentrations of molds which increase sharply in the outdoor air in summer. Because of the difficulty in estimating the outdoor influence, no evaluation proposals can be given for these species for the summer season.

Air Pollution, Indoor↗
PubMed2005

[Quality assurance in the diagnosis of indoor fungi].

In co-ordination with the Umweltbundesamt Berlin, the Landesgesundheitsamt Baden-Wurttemberg (LGA) initiated external quality assurance in the diagnosis of indoor fungi in autumn 2001. Four of six fungal strains commonly found indoors have to be fully identified (on the genus and species level). There are two distributions per year; the six distributions hitherto carried out resulted in correct identification by 46-89% of laboratories (40-71 participants, total 148). It is clear from the results that repeat participants were more successful. In addition to the pure cultures sent out we offered actual samples (two air samples, one wood material, one sample of house dust, hitherto); 43- 69% of participating laboratories also took part in this facultative investigation of actual samples and 29-62% were successful. Results that differed considerably revealed problems while treating and evaluating actual samples. Therefore, activities in this field should be enhanced. In conclusion, external quality assurance in the diagnosis of indoor fungi is a useful management aid in the maintenance and improvement of laboratory performance.

Air Pollution, Indoor↗
PubMed2005

[Molds in air-sampling and detection. Validation of sampling methods to verify molds in air].

The assessment of mold concentrations in air samples requires generally accepted evaluation criteria. It is not possible to derive guideline values based on risk assessment. Background concentrations are therefore used as the basis for the assessment of measured concentrations. The assessment criteria established by the Federal Environmental Agency in Berlin and by the State Health Agency of Baden-Wurttemberg are founded on the experience of some laboratories. The general application of these criteria is only meaningful if validated and generally applied methods of analysis are used. Until now, laboratories have been using many different methods for sampling and detection of culturable molds and total spore counts in air. In this study, different steps for sampling by impaction or filtration are validated. The results presented will contribute to standardization of sampling and detection of molds in air.

Air Pollutants↗
PubMed2005

[Molds in house dust. Sampling and detection].

Examination of dust samples is widely used to detect sources of mold growth in indoor environments. The advantage of this investigation is that house dust can be regarded as a passive sampler collecting mold spores over a long time period. No generally accepted method exists, however, for sampling and analysis of house dust for the detection of molds. Therefore, results obtained by different laboratories are not comparable. Measurements with standardized validated methods are a prerequisite to assess concentrations of molds in indoor environments. The method presented is based on sampling with a modified filter holder (in accordance with VDI 4300 page 8). Mini-sieves of different sizes are used for sample preparation. The fraction <63 microm is used for cultivation of molds after suspension. Problems of dust sampling and preparation are discussed. Criteria for the detection of sources of mold growth based on dust samples are presented elsewere.

Air Pollutants, Occupational↗
PubMed2005

[Background concentrations of molds in air. Determination of mold concentrations in dwellings without known mold infestations in three parts of Germany].

The mold concentration of indoor air and outdoor air in three parts of Germany was investigated in both winter and summer. In total, air samples from 80 dwellings, reportedly free from mold infestations, were analysed with both the cultivation method and the total spore count method. With the cultivation method, 40 mold species and genera were differentiated, while with the total spore count method, 11 spore types were distinguished. The concentration of the genera Alternaria, Cladosporium, Fusarium and yeast increased in summertime. In contrast, the concentrations of Aspergillus and Penicillium measured in summer were nearly equal to those measured in winter. The majority of the various molds were only found in a small number of samples, too small for a reliable comparison of the winter and summer findings. The 95th percentile of the indoor mold concentrations is suggested as the upper limit of the background concentration. The results are discussed comparing the assessment proposals of various authors, and a new assessment proposal is described.

Air Pollution, Indoor↗
PubMed2004

Microthermoforming as a novel technique for manufacturing scaffolds in tissue engineering (CellChips).

The CellChip is a microstructured polymer scaffold, which favours a three-dimensional cultivation of cells within an array of cubic microcontainers. The manufacturing process used so far is microinjection moulding combined with laser-based perforation. In a first attempt to simplify the process, costly perforation was avoided by using commercially available, inexpensive microfiltration membranes for the bottom of the microcavities. Microthermoforming is a promising novel technique which allows the CellChip to be produced from thin film. Working pressures of approximately 4000 kPa were required for the adequate moulding of 50 microm thick films from three different polymers (polystyrene, polycarbonate, cyclo-olefin polymer). Integrating drafts and chamfers in micromoulds is not going to eliminate an uneven thickness profile, but reduces demoulding forces. Microthermoformed CellChips of polycarbonate were perforated by an ion track technique to guarantee a sufficient supply of medium and gases to the cells. The prestructured CellChips were irradiated with 1460 MeV xenon ions at a fluence of a few 10(6) ions/cm2. The tracks were etched in an aqueous solution of 5 N NaOH at 30 degrees C, which resulted in cylindrical pores approximately 2 microm in diameter. Microinjection-moulded, membrane-bonded and thermoformed CellChips were subjected to comparative examination for viability in a cell culture experiment with parenchymal liver cells (HepG2). The cells stayed viable over a period of more than 20 days. No significant differences in viability between injection-moulded, membrane-bonded, and thermoformed CellChips were observed.

Journal Article↗
PubMed2002

Jetlike component in sputtering of LiF induced by swift heavy ions.

Angular distributions of sputtered atoms from SiO2 and LiF single crystals were measured under the irradiation of 1 MeV/u swift heavy ions. In contrast to the almost isotropic distribution of SiO2, an additional jetlike component was observed for LiF. The total sputtering yield of SiO2 ( approximately 10(2) atoms/ion) can be reproduced by an extended inelastic thermal spike model, whereas the huge yield of LiF ( approximately 10(4) atoms/ion) needs a substantial decrease of the sublimation energy to be described by the model.

Journal Article↗
PubMed2001

Microstructured glass chip for ion-channel electrophysiology.

We present a technique by which it is possible to produce a planar sensor for ion channel electrophysiology from glass substrates. Apertures with diameters in the low micrometer to submicrometer range are achieved by irradiation of a glass chip with a single heavy ion and subsequent wet track etching. The function of the device is demonstrated by recordings of single channel currents mediated by the model ion channel gramicidin A in lipid bilayers spanning the micromachined aperture.

Electrolytes↗
PubMed2000

Effect of stress on track formation in amorphous iron boron alloy: ion tracks as elastic inclusions

In a recently developed model of ion beam induced plastic deformation of amorphous solids, ion tracks are described as cylindrical thermoelastic inclusions formed upon local heating and shear stress relaxation along the ion trajectories. According to this model, track formation can be influenced or even suppressed by an applied stress. This model prediction is tested by studying the influence of stress on the etching of tracks of 2.4 GeV Pb in foil samples of the glassy metal Fe 81B 13.5Si 3.5C (2), where a compressive in-plane stress was built up in limited zones by preirradiation with a high fluence of 200 MeV Xe ions. The variation of the size of the observed etch pits with the local stress is found to be consistent with the model predictions, thus confirming the thermal spike origin of the tracks.

Journal Article↗
PubMed1997

Cutaneous involvement in prelymphomatous angioimmunoblastic lymphadenopathy.

We describe prelymphomatous angioimmunoblastic lymphadenopathy with cutaneous involvement in a 73-year-old female patient. A maculopapular skin eruption was the first sign of the disease. Skin histology showed extensive perivascular and periadnexal mixed lymphoid infiltrates including centroblasts and immunoblasts with a high proliferative index and with focal erythrocyte extravasation. Lymph node histology confirmed the diagnosis, showing nearly complete effacement of the follicular architecture, a mixed lymphoid infiltrate, and numberous high endothelial venules in an expanded T-cell zone. Immunohistochemistry, however, demonstrated preservation of at least some follicular structures. T-cell receptor gene rearrangement analysis revealed oligoclonal patterns in both lymph node and skin specimens. In contrast, immunoglobulin heavy-chain gene rearrangement analysis revealed a polyclonal pattern. Accordingly, the disease was classified as a prelymphomatous stage of angioimmunoblastic lymphadenopathy with dysproteinemia (AILD) with specific involvement of both lymph node and skin. The patient was treated with high-dose corticosteroids, and long-lasting remission was induced. In contrast to our case, most reported cases of AILD show a monoclonal T-cell pattern indicating AILD-type lymphoma. Therefore we discuss the concept of prelymphomatous AILD developing into AILD-type lymphoma. Persistence of some antigenic stimulus may induce the proliferation of a monoclonal population of lymphoid cells from a polyclonal background in a multistep fashion. Proper treatment of AILD at an early, prelymphomatous stage may protract or inhibit development of full-blown, fatal AILD-type lymphoma.

Aged↗
PubMed1997

Symmetric lipomatoses in female patients.

BACKGROUND: Symmetric lipomatoses are characterized by marked symmetric deposition of diffusely distributed fatty tissue. Though relatively common disorders, they are rather rarely reported in the literature, possibly being misdiagnosed as general obesity. While the differential diagnosis of symmetric lipomatosis versus general obesity may not appear difficult in males, it is obviously problematic in females. OBSERVATIONS: We describe the findings in 6 representative female patients with symmetric lipomatoses: 3 with benign (multiple) symmetric lipomatosis and 3 with female zonal obesity. The former disorder was characterized by massive, firm, symmetric fat deposition predominantly around the neck and shoulder girdle and was clearly associated with alcohol abuse and/or liver disease. There were no malignant tumors of the upper airways. In the latter case, fatty tissue had accumulated mainly at the buttocks and thighs but characteristically spared the feet and hands. Tenderness was a common symptom. This disorder showed familial predisposition. Histology in both cases revealed normal fatty tissue which was neither encapsulated nor septally divided. CONCLUSIONS: We suggest that the term 'symmetric lipomatoses' refers to two separate disorders, benign (multiple) symmetric lipomatosis and female zonal obesity.

Adipose Tissue↗
PubMed1997

[Mass development of Stachybotrys chartarum on compostable plant pots made from recycled paper].

After handling plants grown in decomposable pots made of recycling paper, three women working in a big horticulture developed very painful inflammated efflorescences at the finger-tips, followed by scaling off the skin. The pots appeared to be very mouldy. Black masses of conidia of Stachybotrys chartarum and perithecia of Chaetomium globosum were identified on almost every pot. Apart from various other fungal genera, Trichoderma und Acremonium were frequently detected. Considering the observed symptoms, special attention was payed to the mycotoxin producing species St. chartarum. To evaluate the inhalative spore load, air sampling was performed. The detection of St. chartarum in the air was only possible with the spore trap (sampling of particles) but not with the Andersen sampler (detection of colony forming units). Without moving the pots, measurements yielded values of 30-100 St. chartarum conidia per m3 of air. The concentration of air-borne conidia increased drastically by handling the pots, thus attaining up to 7,500 conidia per m3 of air for St. chartarum only. The occurrence of St. chartarum in such amounts is alarming because of possible toxin production. In addition, the allergenic stress by fungal spores has to be emphasized. The results are discussed with regard to general medical-mycological aspects related to the degradation of environmentally-friendly decomposable materials.

Acremonium↗
PubMed1996

[Rare variants of cutaneous T-cell lymphomas].

Besides the classical forms of cutaneous T-cell lymphoma (C-CTCL), such as mycosis fungoides and Sézary's syndrome, unique variants may be encountered. The classification of these rare cutaneous T cell lymphomas is problematic and controversial. Newer classifications of lymphoma in general, such as the Revised European-American Lymphoma (REAL) Classification, emphasize well-established clinico-pathological entities. It seems appropriate to attempt to bring greater clarity to the classification of cutaneous T-cell lymphomas using the same principles. In this review, we list and characterize the rare variants of cutaneous T-cell lymphoma, such as (1) clinical, histological and immunological variants of mycosis fungoides; (2) progressive cutaneous T-cell lymphoma (P-CTCL) including transformed classical cutaneous T-cell lymphoma (TC-CTCL) and primary progressive cutaneous T-cell lymphoma (PP-CTCL); (3) angiocentric and angioimmunoblastic cutaneous T-cell lymphomas; (4) large cell anaplastic, CD30+ cutaneous T-cell lymphoma; (5) HTLV-I-associated adult T-cell leukemia/lymphoma (ATLL); (6) cutaneous manifestations of primary extracutaneous T-cell neoplasias; (7) unclassifiable cutaneous T-cell lymphoma.

Antigens, CD↗
PubMed1996

Severe calciphylaxis in a renal patient on long-term oral anticoagulant therapy.

The pathogenesis of calciphylaxis, a potentially life-threatening condition, is not well understood. Several factors such as end-stage renal disease (azotemia), hyperparathyroidism, hyperphosphatemia, hypercalcemia, a high calcium-phosphate product, and the use of steroids and cytotoxic drugs after kidney transplantation are believed to interact in calciphylaxis. Recently, hypercoagulability due to functional protein C deficiency has been suggested to play a pathogenic role in this condition. Here, we present a renal transplant patient, with secondary hyperparathyroidism and on long-term oral anticoagulant therapy, who developed calciphylaxis with severe skin necrosis of her legs. The patient's condition improved dramatically after total parathyroidectomy. Hypercoagulability, therefore, does not appear to have played a significant role in this case of calciphylaxis.

Administration, Oral↗
PubMed1996

Fulminant metastatic calcinosis with cutaneous necrosis in a child with end-stage renal disease and tertiary hyperparathyroidism.

Metastatic calcinosis is a common feature of chronic renal failure. Its first manifestations are bone demineralization and non-visceral and/or visceral calcification with mostly mural deposits in arteries and arterioles. It is initially characterized by hyperphosphataemia followed by secondary or tertiary hyperparathyroidism. Cutaneous involvement is a rare complication. Histologically, the lesions show vascular calcification with ischaemic skin necrosis. Extreme cases may produce calcinosis cutis (calciphylaxis), i.e. disseminated calcification of the subcutaneous tissue and dermis in the form of hard painful cutaneous nodules and plaques with subsequent ulceration. Metastatic calcinosis is a disease affecting adults, while the dystrophic or idiopathic type can develop in children. We present the case of a 6-year-old boy with end-stage renal disease, attributed to congenital renal hypoplasia, and accompanied by secondary hyperparathyroidism. He developed fulminant tertiary hyperparathyroidism and metastatic calcinosis of the lungs, as well as cutaneous necrosis of the buttocks and legs, subsequent to calcification of arteries and arterioles. A maternal renal transplant failed to function. The serum parathormone, calcium and phosphate levels could not be controlled by maintenance dialysis, phosphate binders and calcitriol. Total parathyroidectomy without autotransplantation of parathyroid tissue rapidly returned the serum parathormone, calcium and phosphate levels to normal. In addition, topical treatment using merbromine solution and hydrocolloid dressings, healed the ulcers with significant scar formation, within 2.5 months after parathyroidectomy. A renewed increase of the calcium x phosphate product, 2 months after parathyroidectomy, was attributed to mobilization of calcium compounds from the viscera, as confirmed by a chest X-ray.

Calcinosis↗
PubMed1996

Remission of scleromyxoedema following treatment with extracorporeal photopheresis.

Scleromyxoedema, a disseminated papular and sclerotic variant of lichen myxoedematosus, is a rare disease with a chronic progressive course, and little tendency towards spontaneous remission. The treatment of scleromyxoedema has been largely ineffective. Aggressive chemotherapeutic agents have been used, often leading to therapy-related morbidity and mortality. We report a 41-year-old woman with scleromyxoedema, associated with a monoclonal gammopathy of IgG-kappa type, whose condition almost completely cleared with 12 monthly sessions of extracorporeal photopheresis. The patient had previously not responded to isotretinoin, and chlorambucil with prednisolone.

Adult↗