Biomedical subjects

M Beyer

Publications and source records attributed to M Beyer.

At least 91 records · Page 5Linked to original sources

PubMed1992

[Effect of the starch sources barley, corn, potatoes and their ration fractions on the nutrient digestibility and energy utilization in ruminants. 1. Comparative studies of nutrient digestibility in cattle and sheep].

Rations with energy parts of 50, 25 and 10% from barley, maize and potatoes were investigated comparatively by means of total metabolism experiments with oxen with a view to arriving at a more precise estimation equation of net energy fat for cattle. Parallel to the investigations with oxen the energy and nutrients digestibility of the rations in wethers was measured. The crude fibre content of the rations ranged from 166 to 271 g and the starch content from 69 to 330 g/kg DM. The daily starch intake of the oxen ranged from 575 to 2739 g on nutrition level (NL) 1.7 and from 365 to 1804 g on NL 1.1. The energy digestibility of the rations in oxen with energy parts of 50% barley, maize and potatoes was on average 73.5, 73.9 and 75.3%, of the rations with energy parts of 25% on average 72.2, 71.6 and 72.4% and of the rations with energy parts of 10% on average 68.8, 69.5 and 69.8%. The digestibility of energy and nutrients in cattle and sheep was in good agreement excepted crude protein and crude fat; these were digested 4-5%-units lower from cattle than from sheep. The increase of the nutrition level by one unit lowered the digestibility of rations with energy parts of 50 and 25% from concentrates in cattle about 3-6 units and of rations with energy parts of 10% from concentrates about one %-unit. Information about rumen physiological data is given comparatively between cattle and sheep.

Animal Feed↗

PubMed1992

Comparison of energy deposition and utilization of feedstuffs and rations between growing and adult pigs.

The effect of energy deposition and the utilization of feedstuffs and rations were compared between growing and adult pigs. The good agreement in the data leads to the conclusion, that the energy deposition effect of feedstuffs and rations in growing pigs can be estimated with an equation based on measurements in adult pigs. Exceptions are feedstuffs which are digested bacterially to a relatively high part in the large intestine, as e.g. sugar beet pulp, raw potatoes or similar feed.

Aging↗

PubMed1992

[The energetic utilization of rations with steamed potatoes in growing swine].

The energetic utilization of rations with steamed potatoes (40 and 50% of DM of ration) was measured in 8 growing pigs, live weight 30-70 kg by means of respiration experimental techniques. The experiments were carried out using the difference method (3 periods feeding basal diet and 3 periods feeding basal diet plus potatoes). The digestibility of energy of the steamed potatoes amounted to 94%, that of organic substances 96% and that of crude protein 77%. The metabolizable energy amounted to 16.1 and the energy deposition to 12.0 MJ/kg DM of steamed potatoes, 74.5% utilization respectively. The results in growing pigs are very similar to the results in adult pigs.

Animal Feed↗

PubMed1992

[Neo-angiogenesis after transplantation of a free skeletal muscle flap to the myocardium of the dog].

For the study of the process of neovascularization the effects of the transplantation of a free skeletal muscle flap on the heart of the dog were studied. For this purpose, in 14 mongrel dogs a myocardial infarction of the anterior wall of the heart was produced by the selective injection of microspheres into the left anterior descending artery. In 12 of those, on the area of infarction 4 weeks later a free pectoralis muscle flap was transplanted with its pars anterior in contact with the myocardium (group A). The arterial anastomosis was achieved with the internal mammary artery, the venous flow directed into the right atrium. In 2 other dogs (group B) the pectoralis flap was transplanted with irt pars anterior on a healthy myocardium. In 2 further dogs (group C) the pectoralis flap was transplanted on a infarcted myocardium with its pars posterior, i.e. the muscle fascia interponed. 16 weeks later a microcorrosion-cast-preparation and histological examinations showed in group A and B a prominent capillary network penetrating from the muscle into the myocardium, whereas in group C the muscle fascia inhibited this process. Thus, for the process of neovascularization the "bloody" contact between a skeletal muscle graft and the myocardium is necessary. Results are discussed with regard to possible factors inducing neoangiogenesis.

Anastomosis, Surgical↗

PubMed1992

Cardiac arrhythmias during experimental induction and management of myocardial infarction in the dog.

The experimental production of a myocardial infarction (MI) in the dog was achieved adopting a new catheter technique. After induction of the MI, a variety of arrhythmias appeared and were classified according to the Lown-classification as more or less severe. The therapy was achieved with antiarrhythmics class 1-111 (Vaughn-Williams classification) for late premature ventricular beats or couplets. Sinus tachycardia was often terminated by occular or sinus carotis pressure or a new selective sinus blocking agent. Results showed Amiodarone to be the drug of choice in the treatment of severe arrhythmias (Lown IV and V) like triplets or salves of extrasystolies. Ventricular fibrillation always resulted in the death of the animal, because fibrillation was not convertible by direct current cardioversion, endovenous injection of Lidocaine or even internal cardiac massage. The registration of hemodynamic parameters (left ventricular end diastolic pressure, wedge pressure, pulmonary and aortic pressure) was shown to be important in controlling the therapy, as well as blood gas and electrolyte analysis.

Animals↗

PubMed1992

A cardiac assist device as blood supply in ischemic heart disease.

Before the event of modern bypass surgery revascularisation of the heart was tried with the transplantation of pedicled muscle flaps onto the heart. For patients who cannot undergo bypass surgery this method could be--in a modified way--of help. This was shown in 12 dogs. In those a free muscle flap was transplanted onto the heart which had undergone a previous artificial infarction. The muscle flap was anastomosed with the a. mammaria, venous flow was directed into the right atrium. After 5 months the muscle was almost completely atrophic, but a fit capillary network was penetrating the underlying myocardium.

Animals↗

PubMed1991

Hemodynamic effects of the D- and L-isomers of sotalol on normal myocardium.

This study investigated the hemodynamic effects of the D-isomer of sotalol in open-chest rats and compared this to the action of the L-isomer and the racemic DL-sotalol. Hemodynamic and additional isovolumic maximum measurements were registered at the end and 5 minutes after an intravenous infusion period of 7 minutes. DL- (1 and 2 mg/kg) and L-sotalol (2 mg/kg) caused a significant reduction in the heart rate and in the indices of contractility during and after infusion. D-sotalol (2, 4, and 8 mg/kg), however, decreased the contractility only transiently after very high doses at high plasma concentrations. Thus, while the effects of the beta-blocking L-isomer were comparable to those of DL-sotalol, only a slight and transient hemodynamic action of comparable doses of D-sotalol was found. These findings may be of significance for the proposed use of the D-isomer as a class-III antiarrhythmic agent.

Animals↗

PubMed1991

Reference intervals for serum thyrotropin: dependence on the population investigated.

In order to elucidate possible differences of reference intervals in various populations, serum basal thyrotropin (TSH) was measured in euthyroid healthy volunteers (N = 170), in thyroid out-patients (N = 215), in geriatric (N = 354) and in seriously ill (N = 32) patients. The results, except in the healthy control subjects, were compared to the TSH responses (delta TSH) in the Thyrotropin Releasing Hormone test. Normal ranges calculated from the basal TSH of the euthyroid groups of different age were similar. There was a significant positive correlation of basal to delta TSH in all groups but the regression equations expressing the qualitative connection of basal and delta TSH were rather different. The basal TSH cut off point predicting a positive TRH-test (i.e. euthyroidism) with more than 95% probability was higher in the geriatric groups (greater than 0.7 mU/l versus greater than 0.4 mU/l in the other groups). In thyroid out-patients and geriatric patients a measurable (greater than 0.1 mU/l) basal TSH indicated measurable delta TSH (thus excluding clinical hyperthyroidism), while in seriously ill patients only a basal TSH greater than 0.2 mU/l was reliably predictive in this respect. Thus, various populations have different reference intervals for TSH. This fact must be considered when the sensitive TSH is used in different populations as the primary screening parameter for thyroid dysfunctions.

Adolescent↗

PubMed1991

[The energetic utilization of sugar beets, dried chips, cane sugar and apple pectin by growing swine. 2. Nitrogen and energy metabolism].

The energetic utilization of rations with raw and steamed sugar beets, dried sugar beet pulp (16 measured values each), sucrose and apple pectin (8 measured values each) as supplement feed to a basic ration was measured at 4 growing pigs each in the live weight range of between 40 and 130 kg. The utilization of the energy in the rations amounted to 69.1 +/- 5.5, 68.3 +/- 7.1, 60.9 +/- 5.8, 70.5 +/- 4.1 and 69.9 +/- 6.9% (same sequence as above). The utilization values for the supplemented feedstuffs were 69.2 +/- 7.4, 68.0 +/- 10.0, 55.9 +/- 9.7, 72.2 +/- 7.6 and 71.7 +/- 17.3%. The average retention value of the digestible pectin was derived from the test results with dried sugar beet pulp and apple pectin as 5.8 kJ/g. An influence of the ontogenetic development on energy utilization cannot be derived from the comparison of the retention effect of digestible nutrients measured at growing pigs and that derived from adult pigs.

Animal Feed↗

PubMed1991

[The energetic utilization of rations with dried concentrates, potatoes, sugar beets, apple pectin and cane sugar by growing, intact and ileorectostomized swine. 2. Comparison of results].

Results of the measuring of the total metabolism of growing intact pigs (INT) and pigs with ileorectal anastomoses (IRA) are compared. The 16 comparisons are based on studies with rations of dried feedstuffs and rations containing between 30 and 50% of the DM raw or steamed potatoes and sugar beets, sucrose and apple pectin. On an average of all comparisons the relative values for the digestibility of energy, DM and the organic matter as well as for the metabolizability of the energy were between 81 and 82% (values measured at INT animals = 100). The comparison also refers to the crude nutrients, the water-soluble carbohydrates, the starch and the pectin. As a tendency, the IRA utilized the metabolizable energy better than the INT animals. The energy maintenance requirement of the IRA animals was--by 15%--significantly higher than that of the INT animals. There is not yet an answer to the question in how far comparative studies of INT and IRA animals make verified statements with regard to the differences in the energetic utilization of the precaecally and postileally digested nutrients possible. For this, further experiments will be necessary.

Anastomosis, Surgical↗

PubMed1991

[The energy metabolism of growing swine in the liveweight range of 10-50 kg. I. Study design, feed intake and digestibility].

Studies of the energy metabolism at maintenance and growth levels after the feeding of rations with a crude protein content of 17-24% and 44-47% resp. were carried out with hybrid pigs of line 150 in the live weight range between 10 and approximately 50 kg. This paper gives information on the methods and the outlay of the experiment and presents results concerning feed intake, live weight development and digestibility. Feed intake increased on average with growing live weight by 30-35 g DM/kg live weight. Feed conversion ranged from 1.2 to 1.8 kg DM/kg live weight gain in the first period and from 2.3 to 3.2 kg DM/kg live weight gain in the last period. The digestibility of the energy in the rations with a crude protein content of between 17 and 24% averaged 80% and that of the rations with a crude protein content of 44-47% averaged 86%. In the course of ontogenetic development the digestibility increased up to about 30 kg LW. The influence of the nutritional level on the level of digestibility was unequal in the experiments. In one experiment a decrease (1% unit) and in two experiments an increase (1-3% units) of the digestibility after the feeding of growth level in contrast to maintenance level could be observed. The change of rations with a varying protein content did not result in an influence on the digestibility level in comparison with the constant feeding of one ration.

Absorption↗

PubMed1991

[The energy metabolism of growing swine in the body weight range of 10-50 kg. 2. Nitrogen and energy metabolism].

Investigations were carried out about nitrogen and energy metabolism feeding rations with 17-24 and 44-47% crude protein content on maintenance and growing level to castrated male hybrid pigs of line 150. In growing periods the N deposition amounted to 10 g/animal.d (15 kg live weight), 18 g/animal.d (30 kg LW) and 21 g/animal.d (greater than 40 kg LW) on lower protein feeding level. In experiments with higher protein feeding level the corresponding results were 17, 22 and 22 g N deposition/animal.d. The partial utilization of metabolizable energy for deposition amounted to 70% for the rations with 17-24% protein content and to 59% for the rations with 44-47% protein content, without correlation to the animals development and the alternation in the protein feeding level. The results of regression analysis about maintenance requirement were 814, 775 and 806 kJ metabolizable energy/kg LW0.62.d in trials feeding rations with 17-24% crude protein content as well as 764, 846 and 818 kJ metabolizable energy/kg LW0,62.d in trials feeding rations with 44-47% crude protein content. 1,5-1,8 MJ metabolizable energy were used per MJ protein energy deposition and 1,3-1,4 MJ per MJ fat energy deposition respectively. The energy deposition per kg live weight gain amounted to values between 9 (10 kg LW) and 18 MJ (60 kg LW).

Animal Feed↗

PubMed1990

[Hemodynamic effects of disopyramide on postischemic and normal myocardium].

The acute effects of i.v. disopyramide (1.5 mg/kg) on the hemodynamics of postischemic hearts were investigated in comparison to normal ventricles. Infusion (7 min) was started in rats 20 min after 3 x 4 min of global ischemia during the period of stable postischemic dysfunction. 15 minutes after disopyramide i.v. (vs. NaCl control data) the cardiac output was reduced to 82 +/- 4% (vs. 101 +/- 5%; p less than 0.01) and dp/dtmax to 77 +/- 5% (vs. 83 +/- 3%). The maximum isovolumic pressure generating capacity as load-independent index of myocardial contractility was reduced to 89 +/- 2% (vs. 95 +/- 2%; p less than 0.05). In contrast to the results on postischemic myocardium no measureable change of the hemodynamics was detectable after the identical dose in normal animals without left ventricular dysfunction. Our results indicate an increased sensitivity of postischemic myocardium with modestly reduced contractile function to the hemodynamic effects of disopyramide, especially to the negative-inotropic effects.

Animals↗

PubMed1990

Degradation of phenanthrene, fluorene and fluoranthene by pure bacterial cultures.

Bacterial mixed cultures able to degrade the polycyclic aromatic hydrocarbons (PAH) phenanthrene, fluorene and fluoranthene, were obtained from soil using conventional enrichment techniques. From these mixed cultures three pure strains were isolated: Pseudomonas paucimobilis degrading phenanthrene; P. vesicularis degrading fluorene and Alcaligenes denitrificans degrading fluoranthene. The maximum rates of PAH degradation ranged from 1.0 mg phenanthrene/ml per day to 0.3 mg fluoranthene/ml per day at doubling times of 12 h to 35 h for growth on PAH as sole carbon source. The protein yield during PAH degradation was about 0.25 mg/mg C for all strains. Maximum PAH oxidation rates and optimum specific bacterial growth were obtained near pH 7.0 and 30 degrees C. After growth entered the stationary phase, no dead end-products of PAH degradation could be detected in the culture fluid.

Alcaligenes↗

PubMed1990

[Measuring of the energy turnover in adult swine during feeding of rations with potato starch, potatoes, beets, pressed shreds and coarse fodder as supplements to a basic ration. 2. Evaluation and discussion of the results for further development of energetic feed rating for swine].

Energy metabolism measurings of male castrates of a live weight between 90 and 180 kg after feeding rations with a wide variety in the content of various carbohydrates (crude fibre 36-185, water soluble carbohydrates 25-306, starch 272-683 g/kg DM) formed the experimental basis of the considerations. Energy retention depended significantly on the digestibility and metabolizability of the energy, on energy concentration and the crude fibre content of the rations. By means of multiple regression analyses the energetic effect of 1 g digested matter of the carbohydrate fraction was assessed as follows: 12.9 kJ for starch, 12.1 kJ for disaccharides, 11.5 kJ for the remaining water soluble carbohydrates and 10.4 kJ for bacterially fermentable carbohydrates (BFC). There was a difference between the energetic effective value of starch and BFC. This corresponds completely to the difference in the utilization of metabolizable energy between exclusively precaecal and postileal digestion. The following conclusions are drawn for the further development of the energetic feed evaluation for pigs in the framework of the GDR feed evaluation system: --There are to be differentiated fixed values for the retention of digestible carbohydrates for the fractions starch, water soluble carbohydrates (pectin) and bacterially fermentable carbohydrates. --The influence of the digestibility of the energy in the ration on the energetic retention effect of BFC is small. The integration of these variables into an estimation equation for the energetic feed value is therefore not necessary.

Animal Feed↗

PubMed1990

[Energy requirements of pregnant and lactating sows].

The energy requirement of pregnant and lactating sows is derived on the basis of extensive experimental studies of the energy metabolism (indirect calorimetry, slaughtering) according to the factorial method. For the first reproduction cycle (RC) 0.41 MJ metabolizable energy (ME) or 0.29 MJ net energy fat, pig (NEFpig) resp. were necessary for energy maintenance requirement for pregnant and lactating sows and, depending on age, 0.44 MJ ME or 0.31 MJNEFpig in the second or third RC and 0.47 MJ ME/kg LW0.75.d or 0.33 MJ NEFpig/kg LW0.75.d in the 4th-8th RC. A linear increase of up to 6% of the energy requirement caused by pregnancy between the 85th and 115th day of pregnancy is taken into consideration. Energy requirement per 1 MJ retention both in pregnancy and lactation is 1.45 MJ ME or 1.03 MJ NEFpig, per 1 MJ milk yield it is 1.33 MJ ME or 0.91 MJ NEFpig. 1 MJ body energy for milk yield corresponds to 1.20 MJ ME or 0.82 MJ NEFpig. Equations describing energy retention in the products of conception, uterus and udder are established as well as equations characterizing the connections between live weight gain or loss and energy content of the gain or loss.

Animals↗

PubMed1990

[Negative inotropic effect of flecainide on the post-ischemic heart with limited contractile function].

The hemodynamic effects of 7 min i.v. flecainide were examined in rats with postischemic left ventricular dysfunction. For quantification of contractile function the isovolumic left ventricular pressure generating capacity and dp/dtmax were determined. Fifteen min after infusion the isovolumic maximum pressure was reduced for 33 mm Hg after flecainide (2 mg/kg; n = 12), whereas in the controls only a minimal reduction (12 mm Hg; n = 13) was found; dp/dtmax was also significantly reduced after flecainide. The results indicate - in contrast to prior investigations on normal hearts - a considerable negative action of 2 mg/kg flecainide i.v. on postischemic myocardium with reduced contractile function.

Animals↗

PubMed1989

[Skiing injuries: analysis in a German ski area].

An analysis of frequencies, causes and injury patterns in skiing with emphasis to knee injuries was done. In our clinic next to the slopes of the ski resort Pfronten and the skiing region Ostallgäu skiing injuries contribute with 58% of all stationary treated sports injuries to a big part of our in-patients. Out of all skiing injuries 52% are ligament lesions and 63% concern the knee joint. Thus the knee ligament lesions are leading in our sports related orthopaedic surgery. The results of this analysis were compared with data from Swiss skiing areas and Austrian and German university clinics. Possible ways of injury prophylaxis are presented.

Adult↗