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M Riess

Publications and source records attributed to M Riess.

10 recordsLinked to original sources
PubMed2000

Application of a purge and trap TDS-GC/MS procedure for the determination of emissions from flame retarded polymers.

Emissions of volatile organic compounds (VOCs) from different thermoplastic polymers used in electrotechnical applications were investigated using a purge and trap procedure that involved adsorption on Tenax GR. Results were compared to those for an operating TV set monitored in a test chamber. The analyses were in both cases carried out using thermodesorption gas chromatography with mass spectrometric detection (TDS-GC/MS). Substances identified were monomers, volatile additives, or related compounds. Special attention was given to the detection of halogenated compounds. Their origin was studied using reference samples and synthetic standards.

Air Pollutants↗
PubMed1997

Prejunctional neuropeptide Y receptors in human kidney and atrium.

The aim of our study was to characterize functionally prejunctional neuropeptide Y (NPY) receptors in human and rabbit renal cortex, as well as in human right atrium. Segments of human atrial appendages and of human and rabbit renal cortex were preincubated with [3H]noradrenaline, superfused with Krebs-Henseleit solution and stimulated electrically in superfusion chambers. The stimulation-induced outflow of radioactivity was taken as an index of endogenous noradrenaline release. The effects of subtype-selective NPY analogs on the stimulation-induced noradrenaline release were studied. NPY, its endogenous analog, peptide YY, and its C-terminal fragment, NPY13-36, but not its analog, [Leu31,Pro34]NPY, concentration dependently (1-100 nM) inhibited [3H]noradrenaline release in all tissues studied. NPY-induced inhibition of [3H]noradrenaline release in human and rabbit kidney was abolished by pretreatment with pertussis toxin. We conclude that prejunctional inhibition of noradrenaline release in human heart and human and rabbit kidney occurs through NPY receptors of the Y2 subtype, which appear to couple to a pertussis toxin-sensitive G protein.

Animals↗
PubMed1992

Improved thrombolysis in acute myocardial infarction with front-loaded administration of alteplase: results of the rt-PA-APSAC patency study (TAPS)

Thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) and anisoylated plasminogen streptokinase activator (APSAC) in myocardial infarction has been proved to reduce mortality. A new front-loaded infusion regimen of 100 mg of rt-PA with an initial bolus dose of 15 mg followed by an infusion of 50 mg over 30 min and 35 mg over 60 min has been reported to yield higher patency rates than those achieved with standard regimens of thrombolytic treatment. The effects of this front-loaded administration of rt-PA versus those obtained with APSAC on early patency and reocclusion of infarct-related coronary arteries were investigated in a randomized multicenter trial in 421 patients with acute myocardial infarction. Coronary angiography 90 min after the start of treatment revealed a patent infarct-related artery (Thrombolysis in Myocardial Infarction [TIMI] grade 2 or 3) in 84.4% of 199 patients given rt-PA versus 70.3% of 202 patients given APSAC (p = 0.0007). Early reocclusion within 24 to 48 h was documented in 10.3% of 174 patients given rt-PA versus 2.5% of 163 patients given APSAC. Late reocclusion within 21 days was observed in 2.6% of 152 patients given rt-PA versus 6.3% of 159 patients given APSAC. There were 5 in-hospital deaths (2.4%) in the rt-PA group and 17 deaths (8.1%) in the APSAC group (p = 0.0095). The reinfarction rate was 3.8% and 4.8%, respectively. Peak serum creatine kinase and left ventricular ejection fraction at follow-up angiography were essentially identical in both treatment groups. There were more bleeding complications after APSAC (45% vs. 31%, p = 0.0019).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Long-term acceptance of nasal continuous positive airway pressure therapy in 70 patients with sleep apnea over a 6-month treatment period].

NCPAP therapy is considered to be an effective method of treatment in cases of obstructive and mixed sleep apnea (SA). We investigated its effectiveness during initiation of therapy, and the acceptance of the ambulatory long-term treatment. Here we present the first 70 patients (68 m, 2f) treated with nCPAP for at least six to a maximum of 20 months (on average: eleven months). Sixty-seven of the 70 patients were effectively treated with a nCPAP pressure of 5-15 mbar. The apnea index was reduced from 49 apnea episodes per hour (range 12-125) to 2 episodes per hour (range 0-8) on average. Therapy failed in one case (anatomical defect of the nasopharynx) and had to be abandoned in two cases (claustrophobia, acute rhinitis). Sixty-three patients, decided in favour of ambulatory long-term therapy. These patients were asked to complete a questionnaire about their experience with nCPAP. Four patients abandoned therapy (all within the first four weeks because of intolerance towards the apparatus), and one patient died 10 days after terminating treatment of an infection of the upper airway. Fifty-eight patients (82% of all) are still undergoing treatment. Eighty-eight per cent of these are using nCPAP for 5-7 nights a week throughout the entire sleep period, or at least for five hours. All patients report a marked reduction in or elimination of subjective symptoms. Mild local side effects occur quite frequently, but can be greatly reduced or eliminated in most cases. In individual cases they lead to a shortening of the nocturnal duration of application.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

[Results of left heart catheterization study in 64 patients with nocturnal disorders of respiratory control (sleep apnea)].

Sleep apnea (SA) is associated with increased morbidity of the cardiovascular system, the interaction between the disordering of respiratory coordination and cardiovascular regulation being largely unknown. In 64 patients (age: mean = 54.1; range: 35-67 years) with an increased apnea index (AI greater than 10), a cardiac catheterisation investigation was performed to exclude coronary heart disease (CHD) or cardiomyopathy. CHD was excluded in 39 patients, 6 patients had coronary single-vessel disease, 9 patients coronary two-vessel, and 10 three vessel disease. In 10 patients, cardiomyopathy was detected, while high-grade impairment of the left ventricular ejection fraction (greater than 30%) was observed in five patients. With the exception of a single patient, CHD was observed only in patients in the over-fifty age group. Arterial hypertension was seen in 84% of the patients with, and in 69% of the patients without, CHD. The patient groups with and without coronary heart disease did not differ with respect to apnea index, ten minute index, or the average duration of the 30 longest apneic episodes. Anginal complaints, observed in a total of 72% of the patients, were one of the major indications for coronary angiography. These results do not support the assumption that SA is primarily a consequence of underlying cardiac disease, but do indicate that SA must be considered a cardiac risk factor, especially in view of the fact that pronounced nocturnal changes in blood gases and haemodynamics, together with malignant arrhythmias, are found in conjunction with this disturbance of breathing.

Adult↗
PubMed1989

[Diagnosis of sleep apnea: initial experiences with a staged procedure].

The high prevalence of sleep-related breathing disturbances (SRBD), in association with cardiopulmonary disease, and the impairment by such disorders of the quality of the patients life, together with the good response of SRBD to therapy when diagnosed early on, point up the importance of incorporating the diagnostic evaluation of SRBD into the routine medical and pneumological diagnostic work-up. Since classical polysomnography requires a considerable effort, a stepwise diagnostic procedure was needed for use in practice. This includes a narrowing down of the indications, a brief questionnaire and a detailed questionnaire. For positive demonstration of a respiratory disturbance or differential diagnostic purposes, the following measures are employed on an outpatient basis in the following order: High-resolution 24-hour (Holter) ECG; analysis of heart rate and respiratory sounds, including, in particular snoring, with the MESAM system; induction plethysmography and continuous oxygen partial pressure measurement (pO2tc). Only after exhaustive use has been made of the ambulatory work-up, are the following diagnostic inhospital measures employed in the order indicated: 10-channel recording using the SIDAS system (respiration 3 channels, oxygen saturation, EOG, actogram, heart rate, intrathoracic pressure fluctuations), complete polysomnography. Once SRBD has been established, the patient is sent to the sleep laboratory to establish a baseline. Baseline measurement is accompanied by the determination of a marker, that is, a readily determined parameter capable of providing information about the success of therapy, is established. This permits complete polysomnography to be concentrated on differential-diagnostic and treatment-refractory problem cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗
PubMedDate not supplied

Analysis of flame retarded polymers and recycling materials.

Recycling activities on polymeric materials are increasing and becoming more and more important in recent years. For polymers containing no flame retardants, suitable recycling strategies already exist. In order to investigate the recyclability of flame retarded polymers that contain brominated flame retardants, a number of samples were analysed as received from a recycling company. Following the identification and sorting of the samples according to type of polymers and flame retardants, material recycling was tested for the flame retarded polymers identified to occur most frequently. The reactivity of the flame retardants during the recycling procedure was studied by analysing for brominated dioxins and furans. The results demonstrate that flame retarded polymers can be recycled under certain experimental conditions.

Bromine↗