Biomedical subjects
Publications and source records attributed to A Holzer.
The Otorhinolaryngologist may need information about patients with central language disorders. Some behavioural features and intervention strategies are discussed for evaluating aphasic syndromes.
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Nonesterified fatty acids (NEFA) from C12 to C24 have been determined in sera of 13 young women at menstruation, and in the follicular and luteal phase of the menstrual cycle applying a new gas chromatographic microliter method. Neither the total NEFA content nor the concentrations of individual fatty acids showed significant differences in the three phases of the menstrual cycle. With the exception of stearic acid we found almost constant relative concentration values for the individual fatty acids within the medium range of the long-chain NEFA spectrum. Intraindividual and interindividual dispersion was hardly greater than the variation caused by the method of determination itself, whereas the intra- and interindividual scattering of the rim fractions of the NEFA spectrum was much more distinct. The coefficients of variation for the as well as individual NEFA content related to all examined women at any phase of the menstrual cycle were lower than 40% with the exception of the rare erucic acid, behenic acid and lignoceric acid.
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Non-esterified fatty acids (NEFA) from C12 to C24 are assayed in human serum or plasma in a four-step procedure: extraction, volume reduction, methylation and gas chromatography. NEFA are extracted with chloroform--heptane--methanol from 50--100 microliter of serum or plasma buffered with phosphate. After adding ethyl acetate the volume of the extract is reduced under partial reflux to 5--7 microliter. Potassium carbonate, methyl iodide and a crown ether are added to the dry concentrate and the NEFA are selectively methylated with a yield of 100% by heating in a microrefluxer for 10 min. Gas chromatography is carried out with 1 microliter of the reaction mixture on a packed column by temperature-programmed operation. Thirteen individual fatty acids are determined in sera of normal adults. The coefficients of variation for 24 determinations of a pooled serum were 2.7% for the total NEFA content and 3--10% for most of the individual NEFA.
The respiratory pathophysiology of placental insufficiency is well understood, whereas the metabolic effects of chronical or acute malnutrition still need further evaluation. In a comprehensive study of 20 deliveries respiratory parameters and substrates of carbohydrate- and lipid-metabolism were analysed simultaneously from maternal blood at 4 cm dilatation, at cord clamping immediately delivery and 2 hours post partum as well as from arterial and venous umbical blood samples. Normal deliveries were compared with cases of fetal retardation and moderate acute fetal acidosis. For glucose, insulin, c-peptide and pyruvate a strong rise in maternal blood during labour was observed as well as for the non-esterified fatty acids (NEFA), which have a high materno-fetal gradient. Arterio-venous differences of concentrations were found in the umbilical cord blood for glucose, pyruvate and NEFA. In cases of chronical insufficiency of the placenta especially elevated lactate levels were measured, whereas a moderate fetal acidosis obviously leads to an additional feto-maternal pyruvate transfer. The results lead to the conclusion that the fetal metabolism has considerable means of adaptation during delivery even under chronical or moderate acute stress conditions.
Serum concentrations of non-esterified fatty acids (NEFA) remain unchanged up to the 21th week of gestation in comparison to non-pregnant women; also after the 37th gestational week only slightly increased concentrations are observed in women without labour. Under delivery, however, NEFA in maternal serum are approximately three times higher than those of non-pregnant women. This increase occurs only in NEFA with a chain-length of C12 to C18. Post partum values reach those of non-pregnant women within a few days. The concentrations of NEFA with a chain-length of C12 to C18 in umbilical artery and vein are significantly lower than in maternal serum.
Investigating the for gestationally caused changes and their restitution p. partum we determined in 104 women without metabolic disorders the apolipoproteins A and B respectively in serum, in the main lipoprotein fractions VLDL, IDL, LDL, HDL and in the "rest protein" remaining after separation of the lipoproteins from the serum. In gestation there is an increase in the serum level of apo A of about 30% (p less than 0.001) reaching its maximum in the middle period of pregnancy. The post partal restitution of these changes takes more than 5 weeks happening faster at primarily delactated women. Gestational changes concerning apo A are only caused by a 30% higher concentration of apo A in HDL (p less than 0.001). The serum level of apo B seems to increase continuously meanwhile gestation reaching its maximum from about 60% (p less than 0.001) at the term. The restitution of the gestational changes concerning apo B also requires more than 5 weeks showing no dependence from lactation. The changes of serum apo B are quantitatively most influenced by the 45% higher concentration of apo B in LDL (p less than 0.001), despite the marked changes of apo B in relation to the nonpregnant comparative group found in VLDL and IDL respectively with either 270% (each p less than 0.001). Hyperbetalipoproteinemia in pregnancy was proved in 32%, but in no case the ratio apo B/apo A showed pathological values, because of also raised levels of apo A in these women. By this astonishing phenomenon the gestational hyperlipoproteinemia is characterized as an autonomic metabolic situation, which represents no earlier described type according to the Fredrickson classification.(ABSTRACT TRUNCATED AT 250 WORDS)