Vaginal absorption of oestradiol and progesterone

The vaginal absorption of micronized oestradiol/progesterone from a hydrophilic matrix system was investigated before and after 10 days of treatment in 7 post-menopausal women with an average age of 56.1 yr.

Oestradiol and progesterone levels were measured on days 1 and 11 before administration and 0.5, 1, 2, 3, 4, 6, 8, 12, and 24 h afterwards by radioimmunoassay.

Peak values were seen 6–12 h after administration. This finding differs from those of other investigations. Sex hormone binding globulin (SHBG) and androgen concentrations were unchanged after 10 days of treatment.     

Ultrastructural and biochemical studies on the intestinal absorption of a medium-chain triglyceride (MCT), tricaprylin

The intestinal absorption of a medium-chain triglyceride (MCT) was studied by electron microscopy and biochemical analysis. In jejunal absorptive cells of rats fed tricaprylin, the smooth endoplasmic reticulum in the apical cytoplasm appeared to increase in number and contained one or two particles about 40–80 nm in diameter that were less electron dense and similar in size and profile to very low density lipoprotein. Similar particles were also observed packed in the dilated Golgi sacs and in the extended intercellular spaces. These particles were remarkably increased in number as compared with those in fasted rats. Biochemical analysis of lymph from the main intestinal lymph duct showed that caprylate was apparently demonstrated only in the lymph of rats given tricaprylin at the maximum rate 3h after oral administration. The study strongly suggests that medium-chain triglyceride is at least in part transported via lacteal, possibly in the form of very low density lipoprotein.     

Effects of saline loading on jejunal absorption of calcium,sodium, and water,and on parathyroid hormone secretion in the rat

Summary To investigate whether intestinal calcium absorption parallels that of sodium following extracellular fluid volume expansion, the effects of saline loading on intestinal transport of calcium. sodium and water were studied in rats by perfusing jejunal loops in situ.After calcium-free saline infusion net calcium absorption was reversed similar to that of sodium and water and net secretion occurred. Concurrently, blood-to-lumen (b-l) calcium flux, measured using⁴⁵Ca, increased significantly (P<0.001). Following expansion with calcium-containing Ringer a similar reversal of net calcium, sodium and water flux was also observed. Again, the b-l calcium flux increased but to a significantly lesser extent (P<0.05). Plasma ionized calcium remained unchanged after calcium-rich Ringer loading, but decreased significantly (P<0.001) when calcium was omitted from the solution. Plasma immunoreactive parathyroid hormone was unchanged after expansion with the calcium containing solution but increased following calcium-free infusion.It is concluded that after extracellular fluid volume expansion: 1. net jejunal calcium absorption is decreased; 2. the decrease parallels that of sodium and water; 3. b-l calcium transport is enhanced to a greater degree by calcium-free Ringer infusion than by a calcium-rich solution. This difference could be the result of increased parathyroid hormone secretion.     

Lymphatic absorption and metabolism of orally administered testosterone undecanoate in man

Summary [³H]-testosterone undecanoate ([³H]TU) was administered orally to 4 patients with a thoracic duct catheter after neck dissection surgery.Appearance of radioactivity in lymph, plasma and urine was measured at different times. Metabolites of TU in these fluids were investigated. Peak levels of radioactivity appeared simultaneously in lymph and plasma (2.5–5 h after administration) while the excretion in urine was highest approximately 2 h after the plasma and lymph peak. The main compounds appearing in the lymph were TU and 5-dihydrotestosterone undecanoate (5-DHTU), but 5-DHTU could not be detected. In plasma almost all metabolites were probably conjugated.During the first 24 h approximately 40% of the administered radioactivity was excreted in the urine. The total amount of radioactivity excreted in the urine during the first week was 45–48%. The predominant urinary metabolites were testosterone- and androsterone-glucuronide.The results indicate that TU is metabolized partly in the intestinal wall. The remaining TU and newlyformed 5-DHTU, at least partly, are absorbed via the lymphatic system.     

Status of essential trace metals in biological samples of diabetic mother and their neonates

Objective  There is accumulating facts that the metabolism of essential trace elements is altered in diabetic patients. The aim of present study was to compare the status of essential trace elements, chromium (Cr), manganese (Mn), and zinc (Zn) in biological samples (whole blood, urine and scalp hair) of insulin dependent diabetic mothers (age ranged 30–40) and their newly born infants (n = 76). An age matched 68 non-diabetic mothers and their infants, residing in the same locality, were selected as referents. For a comparative study, the biological samples of non-diabetic and diabetic pregnant and non pregnant of same age group and socio-economics status were also analysed. Methodology  The biological samples (scalp hair, blood and urine) were collected from study and referent groups. The Cr, Mn and Zn concentrations in all three biological samples were determined by a flame/electrothermal atomic absorption spectrometer, prior to microwave assisted acid digestion. The validity and accuracy of the methodology was checked by certified reference materials (CRMs) and using conventional wet acid digestion method on same CRMs. Results  The mean values of Cr, Mn and Zn in scalp hair and blood samples of diabetic mothers and their infants were significantly lower as compared to the referent mothers-infants pairs (p < 0.01), while urinary excretion of all these elements were high in diabetic mother–infant pair samples. Conclusion  The deficiencies of essential trace elements, Cr, Mn and Zn in biological samples of diabetic women, may play role in the pathogenesis of diabetes mellitus and impacts on their neonates.     

自然衰老大鼠不同部位骨组织形态、骨密度及骨代谢指标的变化

背景:大鼠是四足啮齿动物,其骨骼负重方面与直立行走的人类并不相同,且大鼠最大寿限内出现骨稳态破坏的时程变化与人也是不一致的.目的:分析不同大鼠自然衰老过程中骨代谢的变化.方法:将SD大鼠分为雌性组与雄性组,各40只.其中雌性组随机分为雌性7,10,15,20月龄组,各10只;雄性组随机分为雄性7,10,15,20月龄组...     

Nutritional and metabolic consequences of the early Maillard reaction of heat treated milk in the pig

Summary Background During the processing of foods, the Maillard reaction may occur contributing to altering the nutritional value of proteins. In dairy products the formation of lactuloselysine reduces the availability of lysine but the effects on the other nutrients are not very well known. Aim of the study Determination of the consequences of a high level of lactulose-lysine in milk on the bioavailability of skim milk nutrients and the kinetics of their appearance in the portal blood and of their urinary and faecal excretions and extrapolation to lower heat treatments and to man, using the pig model. Methods Sub-adult pigs were fitted, under anaesthesia, with permanent catheters in the portal vein, carotid artery and urethra, and with an electromagnetic flow probe around the portal vein. Each animal was successively fed with two experimental meals containing an equal amount of dried skim milk (SM), either lyophilised or heat treated to obtain an intense Maillard reaction, (M-SM) resulting in a 50 % lysine blockage. Portal and arterial concentrations and flux of individual amino acids (AA), glucose, galactose and fructoselysine were measured for a period of 12h after the meals. Lysine, fructoselysine and AA excreted in the urine and faeces within 72h were also determined. Results In M-SM containing 50 % blocked lysine, no other AA was chemically modified. Fructoselysine appeared in the portal blood very late compared to amino acids resulting from a very slow release and corresponded to 8.2 and 18.6 % of the ingested amount after 12 and 72h, respectively. Significant changes of the appearance in the portal blood were observed only for lysine (−60 %), alanine (−17 %) and cystine (+37 %). A small decrease in the digestibility of most AA during the same period was observed, which was significant after 48h for lysine, phenylalanine, cystine, aspartic acid, glycine and total AA (−6 %). Conclusion It was confirmed that lactuloselysine was not bioavailable. The loss in protein nutritive value was mainly due and proportional to the deterioration of lysine and, to a lesser extent, to the decrease in the digestibility of some essential AA. Taking into account the very high level of lactuloselysine in the M-SM sample studied, it may be concluded that in common foods such as milk, infant formulas, biscuits, bread, pasta, containing lower levels of blocked lysine, the nutritional loss is primarily due to the loss of lysine and to a less extent to the decrease in the digestibility of other essential AA. Received: 24 July 2001, Accepted: 12 November 2001     

NET ABSORPTION OF STARCH IN LOW BIRTH WEIGHT INFANTS

Abstract. Senterre, J. (Department of Paediatrics, University Hospital, Liège, Belgium). Net absorption of starch in low birth weight infants. Ada Paediatr Scand, 69: 653, 1980. —Twelve 3-day metabolic balance studies were carried out in 12 low birth weight infants fed an infant formula providing 3.5 g of corn starch per kilogram body weight per day. The mean coefficients of net absorption were 88±6% for starch, 70±14% for fat and 90±4% for nitrogen. No relationship was found between starch absorption and nitrogen or fat absorption. There was no relationship between starch absorption and the duration of starch feeding. It is concluded that the ability of young infants to digest large quantities of starch is most likely limited resulting from low pancreatic alpha-amylase activity. Nevertheless, from a practical point of view, small amounts of starch in infant formulas can be considered not only as a thickener but also as a source of calories.     

IMPORTANCE OF INSULIN ABSORPTION, SUBCUTANEOUS BLOOD FLOW, AND RESIDUAL BETA-CELL FUNCTION IN INSULIN THERAPY

Abstract. Lauritzen, T., Binder, C. and Faber, O. K. (Steno Memorial Hospital, Gentofte, Denmark). Importance of insulin absorption, subcutaneous blood flow, and residual beta-cell function in insulin therapy. Acta Paediatr Scand, Suppl. 283: 81, 1980.—The interaction between variation in insulin absorption and beta-cell function was studied as well as the possible relation between subcutaneous blood flow through the region of injection and the variability in insulin absorption. The results indicate that the dose of insulin, the type of insulin preparation and the local blood flow influence the insulin absorption. Residual endogenous insulin secretion, governed by the blood glucose values, serves as a modulator.     

THE BIOAVAILABILITY OF ORAL PENICILLIN V. A COMPARATIVE STUDY OF THE ABSORPTION OF DIFFERENT SALTS OF PENICILLIN V IN CHILDREN

ABSTRACT. Different salts of penicillin V (pc-V): potassium pc-V (Calciopen® and Kåvepenin®), calcium pc-V (Penicals®) and benzathine pc-V (Meropenin®) were given to 37 children (age 2 months to 4 years) with upper respiratory infections. The gastrointestinal absorption of the drug given in a mixture was followed for three hours after administration by determination of the serum levels from capillary samples. Administration of the mixtures containing the potassium pc-V resulted in a more rapid absorption and in significantly higher plasma concentrations at 30 min than did administration of the preparations containing the calcium and benzathine salts. In four children with coeliac disease, verified by intestinal biopsy, the absorption of potassium pc-V (Calciopen®) was compared with that of calcium pc-V (Penicals®). A decreased absorption was found and this was most pronounced when the calcium salt was given.