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T Gebhardt

Publications and source records attributed to T Gebhardt.

11 recordsLinked to original sources
PubMed2005

Growth, phenotype, and function of human intestinal mast cells are tightly regulated by transforming growth factor beta1.

BACKGROUND AND AIMS: Transforming growth factor beta1 (TGF-beta1) is expressed in the healthy human intestine and controls mucosal immune responses and inflammation by regulating the function of lymphocytes, macrophages, dendritic cells, and eosinophils. Here, we asked whether human intestinal mast cells (MC) might also be subject to immunoregulation by TGF-beta1. METHODS: MC were isolated from the intestinal mucosa, purified, and cultured in vitro in the presence of stem cell factor (SCF) with or without TGF-beta1. Growth characteristics, phenotype, and immunological mediator release of MC were analysed by reverse transcription-polymerase chain reaction, flow cytometry, immunocytochemistry, western blot, and different immunoassays, respectively. RESULTS: TGF-beta1 dose dependently (ED50 approximately = 0.1 ng/ml) inhibited SCF dependent growth of human intestinal MC by both enhancing apoptosis and decreasing proliferation. In parallel, TGF-beta1 increased the percentage of connective tissue-type MC expressing tryptase and chymase while downregulating expression of the receptors for IgE and SCF. Furthermore, TGF-beta1 dramatically changed the profile of mediators released by MC following IgE receptor crosslinking. Release of histamine, cysteinyl-leukotrienes, and tumour necrosis factor alpha was strongly reduced whereas prostaglandin D2 generation and cyclooxygenase 1 and 2 expression were upregulated by TGF-beta1. CONCLUSIONS: Our data indicate that TGF-beta1 acts as a novel potent inhibitor and modulator of human intestinal MC effector functions. The change in MC mediator release profile and protease expression induced by TGF-beta1 might be of relevance for the control of MC associated disorders of the intestine such as allergic reactions, Crohn's disease, irritable bowel syndrome, and parasitic infection.

Apoptosis↗
PubMed1996

[Chronic persistent cough in general practice: diagnosis and therapy in 329 patients over the course of 2 years].

Chronic Cough: Chronic persistent cough (CPC) lasting from several months to years - without radiographic or spirometric evidence of its cause - was a surprisingly frequent reason (5,7% of all new referrals) to consult our practice. Sophisticated diagnostic evaluation and therapeutic regimen are necessary. We performed a prospective study on 329 consecutive patients (106 male, 223 female) over a two-year period. 65% of the patients had cough as a consequence of bronchial hyperresponsiveness; 27% due to upper airways disease, i.e. often very common rhinitis or pharyngitis; 14% chronic bronchitis; 5% gastrooesophageal reflux (GER); 3% drug induced cough; 4% other causes. 10% of the patients discontinued the diagnostic evaluation prematurely. In 14% the cause for CPC remained unclear and no relief could be achieved. Furthermore, there is a need for consecutive studies to address the following questions: 1. The cause of the striking difference in gender (male : female = 1 : 2) remains unclear. 2. Wether a cough recorder - as occasionally reported in the literature - is needed for an objective evaluation of cough [9]. 3. A standardised methodology of 24 h pH monitoring for the diagnosis of CPC as a consequence of GER has yet to be established.

Adolescent↗
PubMed1989

[Extracorporeal lithotripsy of gallbladder calculi with piezoelectrically generated shock waves: initial experiences].

A piezoelectric lithotripter ("Piezolith 2300") was used in 24 patients for extracorporeal fragmentation of radiolucent gallbladder stones. In 19 patients with one stone and 4 patients with two stones (diameter: 0.8-3.1 cm) fragmentation to a maximal fragment size of 7 mm was achieved. One to three treatment sessions were necessary (mean 1.5). During adjuvant oral litholytic therapy with chenodeoxycholic acid and ursodeoxycholic acid (500 mg each daily up to 80 kg bodyweight and 750 mg in patients with more than 80 kg bodyweight) 4 patients came to be completely free of stones within a mean follow-up time of 15 weeks. Treatment was well tolerated by all patients, no analgesia or sedation was needed. Side effects were cutaneous petechiae in two patients, microscopic haematuria in two others and leucocyturia in another. We conclude that lithotripsy of gallbladder stones can be performed safely and effectively not only by the established underwater spark discharge type of lithotripter but also by the piezoelectric system.

Adult↗
PubMed1986

[Disintegration of kidney calculi with a piezoelectric instrument system. Initial clinical experiences].

Since December 1985 extracorporeal piezoelectric renal lithotripsy has been tested in humans. Up to now 50 patients with renal calculi have been treated. The lithotriptor consists of a special mobile table with an opening in the surface to apply shock waves. Urinary calculi are located by integrated ultrasound location systems. As the piezoelectrically generated high-energy sound pulse does not cause pain, treatment is possible without anesthesia. Permanent ultrasonic control of the stones in the focus during lithotripsy allows effective application of shock waves. With this piezoelectric system the electrocardiogram does not have to be triggered. So far the results have been encouraging and following these tests clinical application is expected to be successful.

Humans↗
PubMed1986

[Disintegration of kidney calculi by piezoelectrically generated high-energy sound waves. Physical principles and experimental studies].

The recently developed equipment for extracorporeal piezoelectric lithotripsy (EPL) represents an improvement concerning the shock-wave-induced disintegration of urinary calculi. While the usual spark gap transmitter needs a focusing reflector, the piezoelectric lithotriptor is based on a self-focusing spherical bowl transmitter. The stone is detected exclusively by ultrasound. For this purpose, an integrated sector scanner is used as well as the high-energy sound transmitter itself. With the piezoelectrically generated high-energy sound pulses we have succeeded in completely disintegrating implanted stones in the renal pelvis of dogs without injuring the morphology or function of the exposed kidneys.

Animals↗
PubMed1978

A comparative assessment of carbuterol, fenoterol and hexoprenaline in allergic asthma.

Carbuterol tablets (2,0 mg) were compared with the tablets of fenoterol (2,5 mg) and hexoprenaline (1 mg). The three drugs were shown to be equally effective for a period of 4 hours, but carbuterol and fenoterol exerted a statistically significant bronchodilating action for 7 and 8 hours respectively, while the action of hexoprenaline lasted for 4 hours in the majority of patients. The aerosols of carbuterol (200 mg) and fenoterol (400 mg) appeared to be similar in inhibiting exercise-induced asthma, whereas hexoprenaline (200 mg) did not appear to be as effective.

Adolescent↗
PubMedDate not supplied

[Extracorporeal shockwave therapy in tendionosis calcarea of the rotator cuff: comparison of different treatment protocols].

AIM OF THE STUDY: Extracorporeal shock wave therapy (ESWT) is a new therapeutic procedure for chronically painful calcifying tendinitis of the rotator cuff. The therapy may vary with the number of applied impulses or with impulse energy. Shock waves with an energy of 0.04 to 0.12 mJ/mm2 define low-dose ESWT, in contrast to high-dose ESWT (> 0.12 mJ/mm2). The aim of the study was to verify the hypothesis that either high-dose or low-dose ESWT could be effective if the total amount of applied energy was similar. METHOD: Fifty patients were assigned at random to 2 groups. The treatment consisted of 3 x 5000 low-dose impulses without anesthesia (group 1) and 1 x 5000 high-dose impulses with intravenous analgesia (group 2). The patients were examined at 6 weeks, 3 and 6 months after treatment. X-rays were performed at each visit. RESULTS: The Constant Score improved from 64.5 to 77.5 (group 1) and from 67.2 to 79.4 (group 2) before and 6 months after treatment (p < 0.05). The values on the visual analog scale which ranges from 0 (no pain) to 100 (maximal pain) improved from 76.8 to 48.8 (group 1) and from 75.4 to 45.6 (group 2) before and 6 months after treatment respectively. The final results for both Constant Score and visual analog scale were obtained after 3 months. X-rays showed a complete or subtotal calcific resorption in 8 (group 1, 32%) and 12 (group 2, 48%) patients. CONCLUSION: Extracorporeal shock wave therapy may be an alternative treatment of calcifying tendinitis of the shoulder. Both treatment protocols gave equivalent results.

Adult↗