Intestinal absorption of D-xylose in the early post-operative period

To assess intestinal absorption in the early post-operative period, portal and subclavian vein catheters were implanted into 8 pigs. For direct d-xylose infusion into the upper small intestine a feeding tube was inserted via a gastrostomy. Four control animals (Group 1) underwent an open and close laparotomy after catheter and tube implantation. Four pigs (Group 2) underwent a standardised ileocoecostomy. At 6, 24, 36, 48 and 72 h after surgery, d-xylose was infused into the small intestine in both groups of animals. After single-dose administration the absorption kinetics were measured in the pre- and post-hepatic blood compartment. With increasing time after operation the rate and extent of d-xylose absorption returned towards normal but there were significant differences in the d-xylose kinetics between the two groups. The absorption kinetics and d-xylose uptake recovered more rapidly in the control group than in those who underwent ileocoecostomy. Effective enteral feeding in controls after 36 h was achieved, but in Group 2 was delayed until 48 h post-operatively. Absorption capacity returned to normal after 48 h in controls and after 72 h in Group 2.

[Use of the stable nitrogen isotope 15N in assessing liver metabolism in hormonal contraception]

In 37 women with long-term use of oral contraceptives (average use 13.4 years) and 12 women who had not taken oral contraceptives for at least 5 years we determined the serum enzymes ALAT, ASAT, Gamma-GT and conducted the 15N-ammonium test as a marker of partial metabolic performance of the liver. In addition we studied total protein, protein fractions in the serum and haematologic parameter. 18 out of 37 women showed a morbid result in the 15N-ammonium test. In 4 of these 18 women morphological changes representing hepatic damage caused by contraceptives could be detected. On the average ALAT, Gamma-GT and 15N-ammonium test in both groups are clearly different. Because the enzymic levels are being in the normal range, only the 15N ammonium test enables to give a hepatotoxic evidence. It is possible to conclude that long-term use of oral contraceptives influences the liver metabolism.

[Aspects of healthy and pathologically changed laryngeal epithelium in a model. 2]

Atrophy of laryngeal epithel at aged men can in model according to the literature lead back on prolongation of mitosis cycles. An increasing tendency of cornification and decreasing formation of pegs in range of basilar membrane are also demonstrable. Formation and development of a tumor instance a pathological evolution of tissue in model.

[Healthy and pathologically changed laryngeal epithelium in a model. 1]

This model attempts to consummate the biological processes of laryngeal epithel on a biophysical basis with the end of prediction optimally therapeutic methods.

[Relations between disordered exocrine pancreas function, alcohol consumption and age in alcoholics]

During clinical withdrawal treatment, a disturbed exocrine pancreas function was found in 28 per cent of 72 alcohol addicts, which occurred in connection with an alcohol-induced pancreatitis. The clinical course was mainly quiescent. Altered bicarbonate concentrations and enzyme dissociations were found as a result of the secretin pancreozymin test. In alcohol addicts, the maximum activity of the amylase output was reached as early as 20 minutes and that of bicarbonate, trypsin and chemotrypsin not until 40 minutes post stimulationem. The sums of the logarithmically transformed 40-minute output of bicarbonate, amylase and trypsin displayed significant differences between the alcohol-addict and control groups. The degree of severity of the disturbed exocrine pancreas function was essentially a function of the daily amount of alcohol taken by the addict and of the age of the patient. The dysfunction was most evident in the 30-to-50-year-old patients. Chronic consumption of alcohol is assumed to give rise to a selective effect on the hydro-kinetic and ecbolic pancreas function.

[Involutional peculiarities of digestion and resorption--deduction of preventive and therapeutic needs]

First indication of an age-related alteration of digestive tract can be proseed an age of fourty. In healthy elderly man functional capacity of nutritions is lowered. Normally the digestive capacity will be sufficient provided a reasonable nourishment. Usually the intestinal absorptive capacity tends to decrease in the elderly. But following delayed intestinal transit of nutritients absorption to a certain degree can occur sufficiently. Considering the nutrition of elderly people recommendations are given.

A modified D-xylose absorption test

A modified D-xylose-test is described which enables intestinal absorption to be assessed independently of renal and hepatic function. The speed of appearance of the peak of D-xylose-concentration in plasma after an oral administrated dose and the extent of absorption in the small intestine as a time-function, were analysed by graphic-mathematical evaluation of the kinetics of plasma D-xylose concentration after oral and intravenous administration. Small intestinal functional integrity was assessed in 172 normal individuals (aged from 3 to 96 years), also in 9 patients with coeliac disease. The speed and the extent of D-xylose absorption were significantly reduced in all cases of untreated coeliac disease and during relapse. There were no differences between normal individuals and treated patients. Experience over many years indicates that the modified D-xylose-test is a simple, reliable and inexpensive standard method for detecting changes in intestinal absorption.

Age-dependent alterations of intestinal absorption. II. A clinical study using a modified d-xylose absorption test

With advancing age functional and morphological changes take place within the intestinal tract. The age-dependency of intestinal absorption has been studied using a D-xylose absorption test. The absorption rate (constant k12), the time of appearance of the relative maximum of the D-xylose concentrations in the blood serum after oral administration (time tm), and the extent of the relative absorption in the small intestine as a function of time RA(t) were determined by graphic-mathematical evaluation of the blood level kinetics of D-xylose after oral and intravenous administration. Within the age range of 3 to 96 yr, it has been proven that a slowing down of intestinal absorption occurs with advancing age. By prolonging the period during which the food components are absorbed in the small intestine (shift of tm towards the absorption processes take place at a slower rate. Absorption disorders in old age are due to morbidity and not, sui generis, to involution.

Age-dependent alterations of intestinal absorption. I. Theoretical aspects

To test the absorption of orally administered D-xylose in the upper small intestine its concentration in the blood plasma must be measured. Absorption is determined as a function of time by subtraction of the blood values found after intravenous administration, which would indicate the rates of metabolism and extraction of xylose by the body. It is suggested that comparison with the behavior of a proposed four compartment model may give a biological interpretation of the results. The possible dependence of amount and rate of absorption can be determined if the same time after feeding of the same diet is used in each absorption measurement. It is suggested that the time point to be used for administration be that time at which the highest concentration of xylose in the peripheral blood is found.

[Senile changes in the resorption and elimination processes and their importance in pharmacotherapy]

On the basis of experimental and theoretical examinations the senile changes in man's absorbent system and renal excretory function were analysed. It was found that intestinal absorption and summary elimination are delayed with advancing years. Practical consequences with regard to dosage and dosage intervals can be derived for geriatric pharmacotherapy. By the example of selected groups of drugs the necessity for revised dosage instructions and application intervals in old age is explained.

[Simulation of the effect of biologically active substances in models]

The results obtained from historadioautographic examinations of the epithelium of the small intestine of rats under the action of procaine served as a basis for examining the proliferative system by using a model. The following results have been obtained through computerized simulation: 1. The maximum life-time of the enterocytes is prolonged at constant villous height, which means that on average the villous is studded with older cells than normally. 2. The prolonged time of generation of the proliferatively active cryptic epithelial cells calls for a pronounced reduction in the pool of reserve cells (cells in the G0 phase, non-growth fraction), i.e. for their activation in order to realize the system characteristics described under 1. 3. The condition of the system induced by procaine may be compared, in its changed tendency, neither to the changing tendencies during aging nor to those under pathological conditions. It is rather a new condition that is being produced and which is characterized, inter alia, by the characteristics described under 1 and 2.

The influence of biologically active substances on the regenerative processes of enterocytes in the small intestine of the rat

The influence of a prolonged treatment with procaine or Turigeran on the cell population kinetics of the mucous membrane of the small intestine was studied by means of 3H-thymidine histoautoradiography in 240 12-month-old male Wistar rats. The investigations produced the following findings: 1. There are no differences in the cell population kinetics of the mucous membrane of the small intestine between procaine- and Turigeran-treated animals. But as, on the other hand, significant differences are found between treated and untreated animals in terms of all cell-kinetic characteristics, this effect has to be attributed to procaine alone. 2. In treated animals the partial stages of the cell cycle are prolonged as a result of which the generation time is delayed. 3. Due to the fact that the transit time of the cells in the crypts and on the villi is reduced, a greater number of labelled cells can finally be observed despite reduced proliferation rates in the crypts (labelling index) of treated animals. 4. Procaine will continue to act with undiminished effectiveness for at least two weeks after discontinuation of treatment.

Age-dependencies in the process of enteric absorption

Founded upon experimental and theoretical investigation at age-dependence of the absorping system in human beings is analysed. Starting from a compartment model the absorption, velocity of absorption and effectivity of absorption are defined in the physical sense. The experimental investigations results in a general decrease of the velocity of all the processes in the absorping system with increasing age. This is the reason for a temporal changed kinetic behaviour of aged systems. By comparison between young and aged systems with reference to their kinetic properties we find the following results: With increasing age we observe a decrease of the velocity of absorption and of the effectivity of absorption, but with regard to the quantity of intestinal absorption not a difference between young and aged is pointed out.

[Enteral resorption in the immediate postoperative phase following selective proximal vagotomy]

The postoperative absorption of the small intestine after selective proximal vagotomy was found out by means of the modified D-xylose absorption test in 23 patients on operating day, and on 1st, 5th, 8th, 9th and, 10th postoperative day. The constant of the adsorption speed was reduced on the operating day and decreased further to the 4th postoperative day. Afterwards the preoperative value was obtained approximately. The temporal state of the relative maximum of the curve of serum concentration (the moment tm) occurred in the same time interval. The tm-value obtained the preoperative value approximately. The dimensions of the absorption in the small intestine was reduced by 36% on the operating day, by 20,5% on the 1st postoperative day, and by 10% on the 4th postoperative day on the arithmetical average. The influence of the gastric emptying after SPV and of gastro-intestinal hormones on the process of absorption was discussed.

Influence of dimethylsulfoxide on transcription by bacteriophage T3-induced RNA polymerase

Dimethylsulfoxide (DMSO) up to 25% (v/v) does not cause irreversible alterations of T3 DNA at 42.5 degrees C as assayed by transcription with T3-specific RNA polymerase. The optimal temperature for the formation of polyanion-resistant ternary complexes of the enzyme, T3 DNA, and nascent RNA chains is lowered by 12.5 degrees C in the presence of 20% (v/v) DMSO. The same solvent concentration, however, decreased the temperature optimal for T3 RNA chain elongation by only 2.5 degrees C, indicating that DMSO preferably affects the initiation of T3 RNA synthesis. DMSO accelerates the loss of T3-specific RNA polymerase activity at 24.5 degrees C. Nevertheless, the speed with which the binary complexes between the phage RNA polymerase and DNA are inactivated by heat (42.5 degrees C) is not altered in presence of 20% (v/v) DMSO. The binding of T3-induced RNA polymerase to T3 DNA in polyanion-resistant ternary complexes is influenced by DMSO which makes the enzyme accessible to the inhibitory action of polyvinyl sulfate. Elongation of T3 RNA chains is slowed down by 20% (v/v) DMSO.

[The aging of intermitotic cells (author's transl)]

The aging of the cells depends on their mitotic activity, which is particularly evident in multicellular organisms. By way of histoautoradiography we studied the cell kinetics on a total of 244 Wistar rats aged 6 days, 6 weeks, 6, 12, 23 and 28 months respectively, with these studies being centred on the mucosa of the small intestine since this mucosa is one of those tissues with the highest cell metabolism. We succeeded in demonstrating that the regeneration rate of cells per hour in the crypts of the small intestine and the migration speed of the enterocytes differ in young and old individuals and that the intermitotic cells have age-dependent properties as well. In addition, we could prove that intermitotic cells too have a non-growth fraction which, at an advanced age, decreases only a little, although significantly in terms of statistics. For the easily vulnerable crypt epithelium it is a reserve capacity and can be included in the proliferating pool, if necessary.

[Postoperative small intestinal absorption after cholecystectomy]

The postoperative resorption in the small intestine after cholecystectomie was found out by means of the modified D-xylose resorption test on the 2-th, 4-th, 6-th an 8-th postoperative day for 14 patients. The velocity and the dimension of the enteral resorption of D-xylose was lower in the immediate postoperative phase. The dimension of the D-xylose resorption was normalized on 4. p. o. day and obtained the preoperative starting-value on the 8-th postoperative day. The myoelectrical activity of the small intestine normalized in a shorter time after cholecystectomy than the enteral resorption. A formal parallelism consists between the normalisation of the motoric activity of the stomach and the xylose-resorption in the immidiate postoperative phase. For the small intestine resorption in the postoperative phase completely clarified and required further investigations. The influences of electrolyte displacement and disturbances of the microcirculation in the postoperative period in the small intestine resorption were discussed.

Effect of temperature on the transcription by bacteriophage T3-induced RNA polymerase

Bacteriophage T3-induced RNA polymerase is rapidly inactivated at 42 degrees C. Addition of T3 DNA delays this process for 30 s and reduces the rate with which the enzyme activity is lost indicating that a labile binary complex between T3 DNA and polymerase must have been formed. The ternary complex between T3-specific RNA polymerase, T3 DNA, and nascent RNA chains obtained when the enzyme is incubated with T3 DNA, GTP, ATP, and UTP is stable to heat (42 degrees C) and only slowly inactivated by polyvinyl sulfate. The optimal temperature for the formation of polyanionresistant ternary complexes is 30 degrees C while the elongation of T3 RNA chains proceeds fastest at 38 degrees C.

[Aging and resorption]

The enteral absorption in dependence of age has been tested by D-xylose. From the additional investigation of the D-xylose reaction in the blood plasma one can detect statistically ascertained age relation in comparison between young and old healthy test persons. Though in old age the absorption process is retarded a sufficient absorption at a longer time at diminished speed of passage of the ingesta in old age.