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T Riedel

Publications and source records attributed to T Riedel.

10 recordsLinked to original sources
PubMed2000

Anticompton spectrometer element studies

Sensitive measurements of the trace elements require the use of an active suppression of the overall detection background. For this reason, an anticompton system made of NaI and HPGe has been constructed at the new underground laboratory in Garching near Munich for analysis of irradiated samples. Significantly improved limits for trace elements' concentration in nylon have been obtained. A suppression factor of 16 in the energy region of 100-400 keV was reached.

Journal Article↗
PubMed1999

[Supply of emergency physicians for patients with stroke in the Münster area. A cross-sectional study of the quality of regional health care].

BACKGROUND AND OBJECTIVE: Advances in understanding the pathophysiology and treatment of stroke have led to changed requirements, including the prehospital phase, for the care of patients with acute stroke. Rapid transport to a regional stroke centre is nowadays considered to be the standard for optimal quality of care. A retrospective cross-sectional analysis was undertaken in 1996 in the region of the town of Münster to test the quality of medical care provided by physicians on emergency call. PATIENTS AND METHODS: 250 of 3001 protocols (8.3%) filled in by emergency call physicians were selected in which the initial diagnosis of transitory ischaemic attack, stroke or cerebral haemorrhage had been made. Quality of patient care was assessed according to the following criteria; (1) complete medical treatment (blood sugar, blood pressure, cardiac rhythm and arterial oxygen saturation, including relevant treatment of any abnormality) (2) action time (arrival of emergency doctor within 12 min and arrival at hospital within 50 min); (3) type of the admission hospital (stroke centre defined as a hospital experienced in the treatment of stroke, with neurological and medical departments, as well as 24-hour cover for computed cranial tomography). A summated indicator of "optimal care" was used to determine whether the three stated criteria were met. RESULTS: Mean age of the stroke patients was 72.3 years. While the above mentioned quality criteria for the action time were met in 93.5% of patients, only 56.0% were admitted to a stroke centre, and this was significantly more often the final destination for patients under the age of 65 years than for older ones (p = 0.049). The quality indicator "complete medical treatment" was met for 27.2% of the transported patients. Measured according to present-day criteria, only 18.6% of patients received such optimal treatment. CONCLUSION: This analysis indicates that modern prehospital treatment of stroke patients does not reach adequate standards. In particular, it is not comprehensive. While the "action time" is usually adequate, there are deficiencies regarding the quality of medical care and the choice of the admission hospital. Further education for emergency physicians with respect to the management of stroke syndrome should be an integral part of any regional quality programme. The number of hospitals with adequate competence in the acute management of stroke cases is still insufficient.

Aged↗
PubMed1999

[The multimodal interdisciplinary therapeutic program in chronic back pain. A new treatment strategy].

The epidemic-like rise in chronic low back pain in western industrial nations is less an expression of a medical than a psychosocial phenomenon. Differentiation between acute, chronic or chronifying pain is of crucial importance for therapeutic procedures. Pain syndromes in the muscular-skeletal system tend to become chronic to a far larger extent than expected. More than 80 % of low back pain represents a functional pain syndrome and does not show any pathoanatomical correlate. Pain existing independently seems to be predestined by a somatic and psychosocial deconditioning syndrome. Those at risk of chronifying pain or those whose pain is already chronic should be given an interdisciplinary, multimodal therapeutic program. A pilot study was carried out in our clinic: multidisciplinary treatment was given to our patients (of which over 90 % belonged to stages II and III on the Gerbershagen scale) and the result was significant improvement in the measurements of pain intensity, sensoric and affective pain perception, their list of complaints, the common scale of depression and the pain disability index. Taking previously published studies into consideration, it is safe to say that a multidisciplinary, multimodal program of therapy even after stay in hospital results in considerable relief of pain and improvement in the ability to cope with the pain for patients with chronified pain syndromes in the muscular-skeletal system which are resistant to treatment on an outpatient basis.

Chronic Disease↗
PubMed1998

[Application of the laryngeal mask for elective percutaneous dilatation tracheotomy].

Percutaneous dilatational tracheostomy is an increasingly accepted procedure for bed-side tracheostomy. The exact positioning of the endotracheal tube, the localization of the point for puncturing the trachea and damage to the endotracheal tube and the cuff as well as to the bronchoscope due to the puncturing process are technical problems which can endanger the course of the operation. In a prospective randomized study, we examined whether use of the laryngeal mask airway (LMA) is a real alternative to the endotracheal tube during tracheostomy. Of 48 consecutive patients only 43 fulfilled all criteria for this study: PaO2 > 100 mmHg, PaCO2 < 45 mmHg (in patients with head injury < 35 mmHg) under intermittent positive pressure ventilation (IPPV) with a mean ventilation pressure of < 25 mmHg and an FiO2 of 1.0. Patients with intestinal obstruction, hemorrhages of the mouth and nose and unfavourable anatomic conditions were not included in this study. Three more patients had to be excluded from the study because of technical problems. In 21 patients tracheostomy was performed using an endotracheal tube (ET group) and in 19 patients using a LMA (LM group). After positioning of the endotracheal tube or the LMA, tracheostomy was performed in the usual way. Arterial blood gases (PaO2 and PaCO2) were investigated before positioning of the endotracheal tube or the LMA, five minutes after this procedure and five minutes after the end of tracheostomy. Mean arterial pressure (MAP), heart frequency (HF) and peripheral oxygen saturation (SpO2), endexpiratory CO2 partial pressure (PetCO2) and minute ventilation volume (MVV) were registered every 60 seconds. The ET group and LM group did not differ regarding basic diseases, age and severity of illness. Before the beginning of tracheostomy, there were no differences in MAP, HF, SpO2, PetCO2 and PaCO2 between the two groups. Before tracheostomy, only PaO2 was significantly higher in the LM group than in the ET group. Immediately before the insertion of the tracheal cannula and five minutes after the end of tracheostomy, there were no differences in the measured parameters of the two groups. An increase in PetCO2 and a decrease in minute ventilation volume were observed in both groups. Regarding technical complications, the LMA is a safe alternative to the endotracheal tube. The choice of method should depend on the basic disease and the patient's ventilation requirements at the time of tracheostomy, while there is still a call for safe instruments guaranteeing sufficient sealing of the respiratory tract during the dilatational tracheostomy and simultaneous avoidance of technical problems during puncturing of the trachea and widening of the point of puncturing.

Adult↗
PubMed1994

Exendin-4 and exendin-(9-39)NH2: agonist and antagonist, respectively, at the rat parietal cell receptor for glucagon-like peptide-1-(7-36)NH2.

Exendin-4 is a novel peptide from Heloderma suspectum venom which is 53% homologous with glucagon-like peptide-1 GLP-1-(7-36)NH2, a stimulant of cAMP-dependent H+ production in rat parietal cells. It was the aim of the present study to determine whether this effect of GLP-1-(7-36)NH2 is shared by exendin-4, and whether the responses to either peptide are blocked by exendin-(9-39)NH2, a competitive specific exendin receptor antagonist. In enriched rat parietal cells H+ production was measured indirectly by [14C]aminopyrine accumulation. cAMP production was determined by radioimmunoassay. [125I]GLP-1-(7-36)NH2 was prepared using chloramine T followed by high pressure liquid chromatography (HPLC) purification. Exendin-4 (10(-12) - 10(-8) M) stimulated [14C]aminopyrine accumulation in a concentration-dependent manner (EC50 = 7.6 x 10(-11) M). At the maximally effective concentration (10(-9) M) exendin-4 was as effective as GLP-1-(7-36)NH2 reaching 70-80% of the response to 10(-4) M histamine. Likewise, exendin-4 (10(-11) - 10(-7) M) stimulated parietal cell cAMP production up to 2.8-fold. Maximal stimulation by exendin-4 of [14C]aminopyrine accumulation was not affected by ranitidine (10(-4) M), but was concentration-dependently reduced by exendin-(9-39)NH2 (10(-11) - 10(-7) M). At the maximal concentration, exendin-(9-39)NH2 completely abolished the responses to 10(-9) M exendin-4 and to 10(-9) M GLP-1-(7-36)NH2 while not altering stimulation by 10(-4) M histamine. Binding of [125I]GLP-1-(7-36)NH2 to enriched parietal cells was displaced by exendin-4 (Ki = 4.6 x 10(-10) M) as well as by exendin-(9-39)NH2 (Ki = 4.0 x 10(-9) M).(ABSTRACT TRUNCATED AT 250 WORDS)

Aminopyrine↗
PubMed1990

[Status of data of HLA-typed donors for unrelated bone marrow transplantation in Hannover: organization and results].

The pool of HLA-A, B and C-typed blood donors in Hannover for cell-donation increased from 2162 in 1988 to 2406 in 1989. 1032 blood donors declared their readiness to donate thrombocytes; 667 would like to donate bone marrow, 453 of them have undergone complete HLA-A, B, C and DR-typing. Until August 31, 1989 we looked in our data bank for an HLA-identical bone marrow donor for 84 patients from other transplantation centers and for 19 patients who are being looked after in Hannover and in national and international data banks.

Blood Donors↗
PubMed1984

Possible association between HLA-DR5 and superficial spreading melanoma (SSM).

Previous analyses of possible associations between MHC determinants and cutaneous malignant melanoma (MM) have been inconclusive. We have investigated 98 patients with special emphasis on histologically determined subtypes of MM, and 5 multiple-case families. In addition to HLA-ABC and DR typing, complement allotypes of C2, C4A, C4B, BF were determined. Among the unrelated patients HLA-DR5 and, secondarily, B49 were observed to be associated with superficial spreading (SSM) but not with nodular (NM) or lentigo maligna melanoma (LMM). In families with MM, no definite segregation of the disease according to HLA and complement haplotypes was discernible. Moreover, no coincidence of haplotypes occurred in patients of the different families. HLA region recombinations including B/DR and/or DR/GLO were found in all the families investigated.

Adolescent↗
PubMedDate not supplied

Oxyntomodulin: a cAMP-dependent stimulus of rat parietal cell function via the receptor for glucagon-like peptide-1 (7-36)NH2.

We have previously shown that in highly enriched rat gastric parietal cells the intestinal peptide hormones oxyntomodulin and glucagon-like peptide-2 (GLP-2) compete for receptor-binding with glucagon-like peptide-1 (GLP-1), a potent cAMP-dependent stimulus of H+ production in vitro. It is, however, unknown whether oxyntomodulin and GLP-2 elicit a biological response by interacting with the GLP-1 receptor. Therefore, we used enriched rat parietal cells to investigate the effects of both hormones on the production of cAMP and H+ ([14C]aminopyrine accumulation). Both parameters were stimulated by oxyntomodulin in a concentration-dependent manner. EC50 values were 6.2.10(-8) and 2.5.10(-7) M oxyntomodulin for stimulation of H+ and cAMP production, respectively. The maximally effective concentrations for stimulation of [14C]aminopyrine accumulation and cAMP production were 1.10(-6) and 1.10(-5) M oxyntomodulin, respectively. At these concentrations oxyntomodulin was nearly as effective as 10(-4) M histamine and equally effective as 10(-8) M GLP-1 (7-36)NH2. In the enriched parietal cell preparation there was no immunocytochemical evidence of contaminating D cells. Accordingly, the responses to oxyntomodulin and GLP-1 (7-36)NH2 were not augmented by incubating the cells in the presence of a polyclonal anti-somatostatin antibody. [14C]Aminopyrine accumulation in response to oxyntomodulin was inhibited by the GLP-1 (7-36)NH2 receptor antagonist, exendin (9-39)NH2, but not by the H2-receptor antagonist, ranitidine. Oxyntomodulin and carbachol acted additively to stimulate [14C]aminopyrine accumulation. GLP-2 (10(-7) to 10(-5)M) was without effect on basal H+ and cAMP production; however, at 10(-5) M GLP-2 markedly inhibited oxyntomodulin-stimulated [14C]aminopyrine accumulation. It is concluded that, by interacting with parietal cell receptors for GLP-1 (7-36)NH2, oxyntomodulin, but not GLP-2, directly stimulates H+ production by activating the adenylate cyclase.

Aminopyrine↗