Biomedical subjects

K Semmler

Publications and source records attributed to K Semmler.

21 records · Page 2Linked to original sources

PubMedDate not supplied

Prevention of congenital malformations in infants of insulin-dependent diabetic mothers.

From April 1977 to April 1981, 420 deliveries of infants of insulin-dependent diabetic women were performed in our department. Of the infants delivered, 23 had congenital malformations (5.5%). The malformation rate was 1.4% for infants of 420 nondiabetic women. Strict metabolic control was begun after 8 wk gestation in 292 of the diabetic women who delivered 22 infants with congenital malformations (7.5%). Intensive treatment was begun before conception in 128 diabetic women planning pregnancy. There was only one malformation in infants of this group (0.8%), a significant reduction from the anomaly rate in the late registrants (X2 = 7.84; P less than 0.01). These observations indicate that reasonable metabolic control started before conception and continued during the first weeks of pregnancy can prevent malformations in infants of diabetic mothers.

Congenital Abnormalities↗

PubMedDate not supplied

The effect of sterols on structures formed in the gel/subgel phase state of dipalmitoylphosphatidylcholine bilayers.

The effect of cholesterol and lanosterol on the formation of structures in the gel/subgel phase of 1,2-dipalmitoylphosphatidylcholine was investigated using freeze-fracture electron microscopy and X-ray diffraction. Mixtures with up to 25 mol% sterol were analysed after annealing for between several days and some months at 4 degrees C. Bilayers of DPPC with 5 or 10 mol% sterol showed a domain structure in the gel state. There are rounded or lens-like and often inclined plates within less smooth either plane or striped bilayer areas. The stripes are formed by parallel lines separated by a distance of 30-60 nm. Parallel lines can be induced also in the less smooth but plane areas by warming up to 25 degrees C. X-ray diffraction showed two lamellar repeat spacings at 6.45 and 8.3 nm in both 5 and 10 mol% samples. The plates are interpreted as domains of (nearly) pure DPPC within the sterol containing bilayer. Stripes are present if the concentration of cholesterol is below a critical value (approx. 15 mol%). With time of incubation at 4 degrees C curved deformations appear in parts of the bilayers. Two main types are formed. The small type has a repeat distance of about 100 nm and the large type of about 400 nm. The curved deformations were progressively flattened by warming up to 25-32 degrees C with an accompanying reappearance of stripes but no plates. After prolonged annealing at 4 degrees C there is also the formation of regular ripples. It is concluded that in presence of 5 and 10 mol% sterol in bilayers of 1,2-dipalmitoy-phosphatidylcholine the immiscibility of gel phase and subgel phase changes during prolonged annealing at 4 degrees C. We assume a rearrangement of the molecules into a homogeneous phase state with liquid-ordered properties.

1,2-Dipalmitoylphosphatidylcholine↗

PubMedDate not supplied

[Morphology of the placenta in relation to glycemia status in pregnancy in diabetes mellitus].

Morphological investigations in 569 placentas of diabetic women have been performed. The histological results of 300 placentas from diabetic women delivered between 1969 and 1973 were compared to 269 placentas of diabetic women from the time period 1979 to 1983. The latest time period was characterised by normoglycemic metabolic control throughout pregnancy. Besides the morphological findings clinical results especially the perinatal mortality and morbidity during the two time periods are discussed. Morphological changes in the placenta of diabetic women are depending one the quality of metabolic control during pregnancy, independing on the White classes. Normoglycemia reduces placental maturation disorders, perinatal mortality and morbidity.

Birth Weight↗