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Presents information on a study which investigated the effect of ageing on the circulatory system in middle-aged men during thirty-three years of aerobic exercise. Methodology; Results of the study; Discussion.

In femtosecond Laser Ablation Ionisation Mass Spectrometry (fs-LIMS) short laser pulses are used to ablate, atomise, and ionise solid sample material shot-by-shot. When ablating non-conductive samples electric charging of the surface can occur. Depending on the geometry of the instrument, the surface charge can influence the spread of the ablation plume and reduce spectral quality. Methods to reduce surface charging were investigated using a non-conductive geological sample and a miniature fs-LIMS system with a co-linear ablation geometry. Pausing five seconds between consecutive laser bursts fired on non-coated material improved the spectral quality by giving surface charges more time to dissipate. However, best mass spectrometric results were achieved after the sample was sputter coated with a thin gold layer, as a conductive sample surface hinders charge build-up. Consequently, gold coating allowed operation of the laser system at much higher laser pulse energies improving sensitivity and reliability. It also removed the need to pause between laser bursts, speeding up the measurement acquisition., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Objective: The emergency department (ED) is a demanding environment, and critical events have been identified as contributors to stress. Debriefing is a possible intervention for staff, but there is little information regarding formulation and implementation. A needs assessment was conducted to describe the emotions of pediatric ED (PED) staff following critical events and assess opinions regarding debriefing., Method: This mixed methods study used convergent design for triangulation. After critical cases, PED staff members were given the Peritraumatic Distress Inventory (PDI). Additionally, a questionnaire with 2 open-ended questions on debriefing was administered. Themes were extracted from the questionnaire using directed content analysis., Results: A total of 719 responses were collected for 142 critical cases. Physical reactions were often endorsed in the PDI, and these reactions were mirrored in the qualitative data, which included physiological responses such as stress, adrenaline high, anxiety, fatigue, and overwhelm. Helplessness and grief were 2 of the emotional PDI items frequently endorsed, which were reflected in the qualitative strand by themes such as helplessness, sadness, disheartenment, and regret. There was considerable variability between critical cases such that not every critical case elicited a desire for a debrief., Conclusions: PED staff report measurable levels of stress after critical patient cases that warrant follow-up. Formal debriefing immediately after critical patient cases with specific caveats may be valuable for the reduction of stress. Any formal debriefing program will need to balance various goals with attention to the session length, setting, and timing., (Copyright © 2022 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

A novel H(2) molecular adsorption state on metal surfaces has been detected by temperature-programmed desorption and electron energy loss spectroscopy experiments of the H(2)/Pd(210) system. The molecular nature of this state has been verified by isotope exchange experiments. This molecular state leads to a decrease of the surface work function while atomic hydrogen on Pd(210) causes an increase. Ab initio total-energy calculations have confirmed all experimental findings. Through these calculations the microscopic nature of this novel molecular adsorption state could be identified; it turns out that this state is stabilized by the presence of atomic hydrogen on the Pd(210) surface.

Here we report the first observation of hyper-Rayleigh light scattering from bacteriorhodopsin in the form of an aqueous suspension of unoriented purple membranes. A typical purple membrane suspension used in our experiments contains approximately 10(8) randomly oriented purple membranes. Each purple membrane contains approximately 10(5) bacteriorhodopsin molecules in a two-dimensional crystallinearray. Hyper-Rayleigh light scattering is observed when the purple membrane suspension is illuminated with light that has a wavelength of 1064 nm. We propose that the 532-nm scattered light from each of the bacteriorhodopsin molecules in a single purple membrane is coherent, and that the scattered light from different purple membranes is incoherent. This proposal is supported by the following experimental observations: (a) the 532-nm light intensity is proportional to the square of the incident power, (b) the intensity of the 532-nm signal is linearly proportional to the concentration of purple membrane in solution, (c) the scattered 532-nm light is incoherent, (d) the scattered 532-nm light intensity decreases if the size of the purple membranes is reduced while the bacteriorhodopsin concentration is kept constant, and (e) the 532-nm light is due to the retinal chromophore of the bacteriorhodopsin molecule. The ratio of horizontal polarized hyper-Rayleigh scattered light to vertically polarized hyper-Rayleigh scattered light gives the angle (23 ± 4°) of the retinal axis with respect to the plane of the purple membrane. The hyperpolarizability of the bacteriorhodopsin molecule is found to be 5 ± 0.4 × 10(-27) esu.

72 patients at the age of 44 to 76 years with transitory ischaemic attacks which happened and for a short time reversible deficits, respectively, were diagnosed both conventionally duplex-sonographically and with the colour-coded duplex sonography under the question of vascular stenotic process in the region of the cervical vessels. After the ultrasound examination within two weeks an angiography was performed. As a result was shown that in 10 patients with an angiogram without pathological findings by means of the colour-coded duplex sonography in 3 cases plaque formations could be proved which could be clearly diagnosed only by colour marking.

The effects of pimobendan (UD-CG 115) on hemodynamics and exercise capacity after acute (single dose) and chronic (6 month) oral treatment, as well as acute treatment after 6 months were investigated in 67 patients with chronic heart failure of NYHA classes II or III, which had persisted in spite of treatment with diuretics and digitalis. They were treated with pimobendan (2.5 mg bid or 5 mg) or placebo in a randomized, double-blind multicenter trial. With a single administration before and after 6 months' treatment there was-compared to placebo-a significant fall in pulmonary capillary pressure (PCP) at rest (R) and during exercise (E) of 7% to 24%. Right atrial pressure (R) and pulmonary arterial pressure (PAP) (R, E) decreased after pimobendan on day 1; cardiac index (E) increased significantly. All other parameters were not influenced. After chronic therapy, PCP (E), PAP (E), LV stroke work index (E), and pulmonary resistance (R and E) values were significantly lowered by pimobendan when compared to day 1. Exercise duration was prolonged after 6 months by 83 s and 47 s after 5 and 10 mg/day, resp., compared to the placebo group (group difference not significant). Subjective wellbeing was improved in all three groups (no group difference). Clinical symptoms were not altered; six patients (two in each group) died suddenly. Another nine patients discontinued the trial prematurely because of poor efficacy or adverse events (no group difference). Overall, pimobendan was well-tolerated and had favorable effects on both acute and chronic hemodynamics and on exercise capacity. There was no evidence of any tolerance development.

In the investigation 17 patients with lung embolism being cared for with a Guenther-filter were post-observed during a period up to two years. Early complications after the implantation of the Guenther-filter did not occur in any case. Late complications after the implantation of the Guenther-filter were dislocations, deformations of the filter and breaks of the spokes. In the result of the post-observation the Guenther-filter application despite its easy handling should be regarded very critically.

72 Patients with occurred transitory ischemie attacks and passed reversible neurologie deficits were duplexsonographically diagnosed. After wards a renewed duplexsonographic investigation with color coding followed in all patients. The patients were angiographically diagnosed within two weeks. As a result in three of ten patients with an unobtrusive angiogramm plaques formations were proved by means of the color codes duplexsonography.

In the present paper the courses of the disease of 117 patients who due to an acute cerebrovascular insufficiency were admitted to the angiological department of a Dresden county hospital in the period from January 1989 to June 1990. Early complications which were frequently observed were urinary tract infections, pneumonias and recidivations of insult. On the basis of the results of examination can be confirmed that the prognosis is decisively determined by the ability of mobilisation during the first days.

In the cerebrovascular disease the EEG can give references at localisation, extension and course. The ability of statement is increased by methods of provocation and activation. On 35 patients with cerebrovascular insufficiency can be indicated that there are good correlations between changes on the large cerebral supply vessels and changes of the EEG, in particular in the carotid pressure trial.

On account of cerebrovascular insufficiencies or asymptomatic vascular noises which had taken place 45 patients were examined by means of Doppler sonography and after this by means of angiography. The judgement of the common carotid artery, the internal and external carotid arteries, the vertebral artery, the subclavian artery and the supratrochlear artery were involved into the ultrasound investigation. The sensitivity of the supratrochlear compression test was 50% in the diagnosis of high-degree stenoses and occlusions of the internal carotid artery, whereas the sensitivity of the complete ultrasound investigation way about 80%. The advantages and disadvantages of the ultrasound Doppler sonography investigation are discussed.

Thirty-eight skinfold calipers were compared in terms of dial accuracy, downscale force, and pressure at jaw openings of 10, 20, 30, 40, and 50 mm. Dynamic measures were made on four thicknesses of foam rubber. Foam rubber was used to simulate the compressibility of skinfolds and to eliminate subject and tester variability. Five caliper types were tested: 10 Harpenden (HRP), 9 Lange (LNG), 12 Slim Guide (85SG), 4 Skyndex (SKN), and 3 Lafayette (LF). Within-type variation was small and consistent across openings for dial accuracy, force, pressure, and foam rubber compressed thickness. Between-type pressures differed (p less than 0.01), with the HRP and LNG calipers having the highest but similar pressures and the SKN, LF, and 85SG calipers having the lowest but similar pressures. LF and LNG calipers (which differed from each other) had higher compressed foam rubber means than HRP, SKN, and 85SG calipers (p less than 0.01), which were similar to each other at three of four thicknesses. When average pressure was used as the covariate, differences between types were still large, with 97.5-99.3% of the variation explained by type. Compressibility of foam rubber was shown to be caliper specific. It is concluded that there are static and dynamic differences between the five major types of skinfold calipers. When measurer error is eliminated, the HRP, 85SG, and SKN calipers are similar to each other, but they give lower values than the LNG or LF calipers by approximately 50-100%, depending on compressed thickness. These differences should be noted when comparing skinfolds measured with dissimilar calipers.

In 30 patients suffered from acute myocardial infarction the serum levels of zinc, copper, cortisol, aldosterone, and triiodthyronine were determined. Zinc and triiodthyronine decrease, the other parameters increase. The serum levels of the tested parameters show a characteristic course within the first days after onset of myocardial infarction. There are significant differences between patients without complications and patients with complicated course inclusive of deaths. The differences exist already on the day of admission. Therefore we conclude zinc, copper, cortisol, and aldosterone levels as well as the course of T3 level are useful for prognosis of the clinical progress fo AMI. The tested parameters are helpful in differential diagnosis of chest pains caused by myocardial ischemia with or without myocardial infarction. The strong correlations between trace elements and hormones show new aspects due to the explanation of pathological alterations of serum levels in clinical medicine.

The application of an enzyme immunoassay for plasma renin activity in clinical diagnosis was studied and the following findings were obtained: 1. In patients with primary aldosteronism, very low renin activities were found. On the other hand, increased renin levels were observed in patients with secondary aldosteronism (renal artery stenosis, malignant hypertension, Bartter's syndrome). 2. Plasma renin activity was found to be considerably increased in Addison's disease. Measurements of Plasma renin were a guide-line for appropriate mineralocorticoid substitution in those patients. In 6 patients with salt-losing congenital adrenal hyperplasia due to 21-hydroxylase deficiency, the renin activity was also elevated and normalized after corticoid treatment. 3. During pregnancy, the renin levels showed an increasing tendency from the first to third trimester. Women with pre-eclampsia showed higher values than normal pregnant women. 4. An age-dependent change of renin activity was observed in newborns and children, especially markedly increased values during the first 5 days of life. 5. During the normal menstrual cycle the renin levels increased to a maximum in the mid-luteal phase. A significant increase of renin activity was found in women taking oral contraceptives. Previously, we reported on the determination of renin activity by an enzyme immunoassay (EIA) (Hubl et al., 1980). In this study, we examined the clinical application of this EIA.

The expert opinion on chronic arterial hypertension contains several problems, such as influence on choice of the profession and change of the profession, judgement of the traffic ability, judgment of the ability for military service, judgment of connective questions and judgment of capability of earning a living. Of particular importance is the expert opinion the following criteria shall be submitted to a complex valuation: etiology and degree of severity, therapeutic influencibility, physical efficiency, use of rehabilitation measures, side-effects of medicaments, prognosis of hypertension, taking into consideration the natural course and the complications after sufficiently long time fo observation and under optimum use of therapeutic and rehabilitative measures.

30 patients underwent implantation of the Mobin-Uppin filter for recurrent life threatening pulmonary embolism. 20 patients could be followed by phlebography. In 11 cases obstruction of the inferior vena cava was observed. Due to the collaterals having developed in the intermediate time there were no significant clinical symptoms below the obstruction.

Eight cases of Lyme borreliosis of clinical certainty with carditis are reported. In six patients, AV-blocks were predominant, two patients had a myopericarditis. Six acute cases were seropositive, but one case remained seronegative. The titer was border-line in that patient, who was studied 4 years after the acute disease. A Lyme carditis should be considered in each case, in which AV-blocks appear acutely.

It is reported on a new catheter technique for the determination of the cardiac output by means of the method of thermodilution. It consists of a thin sensorcatheter (3 Ch), which contains a microthermistor as temperature sensor and additionally two electrodes. The insertion of the catheter is carried out via puncture of the subclavian vein by means of a special introducer set, the outer sheath of which can used for injecting the cold solution. The positioning of the sensor catheter into the pulmonary artery may be done by intracardiac ECG monitoring with the help of the two electrodes. By means of these electrodes, however, also an electric stimulation of the right ventricle is possible, so that, for instance, haemodynamic investigations depending on stimulation parameters can be performed by only one catheter. The clinical test of the new catheter-set was very successful.

The problems of the phaeochromocytoma are in its rareness, its appearance--every patient with hypertension can be a carrier of a phaeochromocytoma--, its localisation--10% are situated outside the adrenal glands--, its operability with following permanent normalisation of the pressure. As hypertension is very frequent and the diagnostics is very expensive the finding of carriers of phaeochromocytomas is possible only by means of screening methods. Thus cases with an urgent suspicion are found. Such a method is described, the basis of which is a semiquantitative determination of the vanillic amygdalic acid. Instead of the usually used diazocolour-reagent in connection with a non-optimal buffer a complete nitrophenylantiazotate with a buffer of high ionic strength is taken. The pH-value 10 of the urine which is to be demanded for the colour reaction is thus reached in every case. In order to avoid falsely normal results with every urinary test a preparation with added vanillic amygdalic acid is performed and thus the presence of colour inhibitors is recognized. If the result is pathological a quantitative determination is necessary.

After indications to the great epidemiologic importance of hypertensive heart disease and its relationship with the ischaemic heart disease several results are reported collected during the past 10 years by examinations of more than 500 patients for early diagnosis of cardiac insufficiency in hypertension. The methods of microcatheterization of the pulmonary artery and radiography have been used (even under ergometrical exercise) as well as the calibrated apex cardiography and the echocardiography. For the practising physician a classification of hypertensive heart disease with 4 phases or forms is proposed. The paper ends with a demonstration of the close relationship between prevention and treatment of hypertension as well as between hypertensive and ischaemic heart disease at the same time in a sense of the integrative role of heart insufficiency.

Of the parameters in consideration for control of physiological rate responsive pacing special interest is directed to stroke volume. In search of indirect parameters which are correlated to stroke volume it is demonstrated on principle that systolic time intervals could be used. From the relation ejection time versus pre-ejection time (LVET/PEP) which is known for its correlation to stroke volume a simple algorithm is derived which is based on the realization that PEP is related to the reciprocal of cardiac output. First investigations with patients demonstrated the possibility of the computation of heart rate from PEP only, with good physiological significance.

In the sick sinus syndrome, in sinu-atrial conduction defects or in atrial flutter or fibrillation a stress-adapted, frequency-adapted stimulation cannot be obtained by the processing of the atrial potential. Here one depends on partly extracardiac parameters which contain informations about the metabolic and stress situation, respectively. A survey of the parameters for a frequency-adapted stimulation discussed at present is given and a critical valuation of them is carried out. It is shown that all parameters up to now experimentally and clinically, respectively, tested are more or less problematic and that the way out of the difficulty most consist in deriving the controlled variable for a stress adapted stimulation rate from several parameters.

The purpose of these investigations is to refer to the possibility of the reconstructive treatment of arterial obstructions by means of streptokinase. New application methods improved the chances of success of fibrinolysis. They run about 50%. The local application of smaller doses of streptokinase confines the contraindications to a certain extent. Obstruction in the pelvic area which are not older than three months and such ones in the femoropopliteal part up to 6 weeks are to be regarded as indication to the fibrinolysis. In the care of patients with arterial obstructive diseases importance should, therefore, be attached to the fact that thrombotic shifts should be recognized in time an the possibility of a fibrinolytic therapy is tested within the periods mentioned.

It is reported on the properties of the new catheter-tip pressure transducer IBW-79 (Ch 5) for applications in the left heart. The approach to the left ventricle was carried out with the help of Seldinger-technique (Ch 10) via A. femoralis. In all cases positioning of the pressure transducer in the left ventricle succeeded, but in 2 out of 12 patients there were complications after diagnostic program caused by the puncture. The pressure measurements were from a high quality and high fidelity. Zero shifts during the measurements were in the order of -0.5 kPa (-3.8 mm Hg), directions are given for correction or compensation. In our opinion the IBW-79 is a valuable new sensor-catheter for measuring the pressure in the left heart, above all for scientific applications.

The construction and the mechanical properties of a percutaneous, transvenous implantable thrombus filter on the pulmonary embolism prophylaxis is introduced. The pressure loss by this filter amounted to nearly 1/60 in comparison with the Mobin-Uddin umbrella filter. The effect of partial occlusions by thrombus is estimated theoretically by means of technical models. The anchoring of the fresh implanted filter is guaranteed in case of embolisation with covering up to 85% of the open surface. A much faster anchoring is to be expected by reaction of the tissue after few days. It also resists in the most unfavourable case imaginable.

It is reported on a new semiconductor-microtransducer with integrated pressure and temperature sensor for simultaneous intracorporal pressure and temperature measuring. The properties of the pressure and temperature canal are described in short and first clinical applications (pressure measuring of the right heart, determination of cardiac output by means of thermodilution). Further applications are discussed.