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F Klink

Publications and source records attributed to F Klink.

72 records · Page 4Linked to original sources

Molecular genetic evidence for early evolutionary origin of budding peptidoglycan-less eubacteria.

Recent studies on the cell wall composition of budding, non-prosthecate bacteria have shown that representatives of the genera Planctomyces and Pasteuria (sensu Staley, 1973) lack the peptidoglycan moiety, which is the characteristic feature of eubacterial cell walls, but possess an as yet unidentified protein sheet instead; in this respect Planctomyces and Pasteuria strains resemble certain archaebacteria more than eubacteria. To determine their phylogenetic positions, the 16S ribosomal RNAs of three budding, peptidoglycan-less strains with and without stalks were subjected to partial sequence analyses. As we report here, the comparison of data with those obtained from about 320 eubacterial and 40 archaebacterial strains revealed that the strains investigated are not members of the archaebacterial kingdom but represent an ancient line of descent of the eubacterial kingdom. Furthermore the diphtheria toxin reaction of Planctomyces and Pasteuria shows that they behave like eubacteria.

Bacteria↗

Two contrary modes of chemolithotrophy in the same archaebacterium.

Sulphur-dependent archaebacteria, which are found around nearly boiling continental solfataric springs and mud holes, can be assigned to two distinct branches: the aerobic, sulphur-oxidizing Sulfolobales and the strictly anaerobic sulphur-reducing Thermoproteales. Here, we report the isolation of a group of extremely thermophilic solfataric archaebacteria that are able to grow either strictly anaerobically by reduction, or fully aerobically by oxidation of molecular sulphur, depending on the oxygen supply. We have also established that the ability to grow in these two ways is shared by Sulfolobus brierleyi, a well-known less thermophilic sulphur-oxidizing archaebacterium capable of ore-leaching. The phenomenon may be dependent on a fundamental switch in genome expression. These organisms might represent the primitive fore-runners of sulphur-oxidizing archaebacteria, meeting their energy requirements either by oxidation or by reduction of the same element.

Archaea↗

[Chromosomal mosaicism after diagnostic chorionic villi biopsy. Subsequent study of the placenta].

Among 311 diagnostic chromosomal analyses after CVS eleven results (mostly chromosomal mosaicism) did not fit completely with the chromosomal sets found in the fetuses and newborns. In all cases chromosomal mosaicism was restricted to the placenta only. All children born after the diagnosis of a chromosomal mosaicism in the placenta were normal. In six cases the investigation of the placenta after termination of pregnancy or birth was possible. In all those cases the mosaicism could be found within the placenta, however, in some cases in a very low percentage. Although occurrence of chromosomal mosaicism in the placenta can hinder chromosomal diagnosis after CVS, the advantages of the method are not neutralized.

Abortion, Eugenic↗

[Risk of infection in premature infants with premature rupture of fetal membranes in correlation to respiratory distress syndrome].

The spectrum of infective agents in 58 preterm deliveries with premature rupture of the membranes (PROM) is examinated by assessment of bacteriological swabs. In the earliest weeks of gestation all children had severe RDS. Nearly 40% of the detected pathogens belonged to the non pathogenic vaginal flora. E. coli, Streptococcus species, Klebsiella and Candida were predominant in the group of facultative pathogenic infective agents. There is an enlarged colonization in maternal swabs after greater than 24 h. In nearly 80% of the children with severe RDS pathogens could be detected. Ascending infection is followed more often by severe RDS. In case of premature labor refractory to tocolytic therapy or slight vaginal bleeding, cervical swabs should be taken. Pathological findings must be treated by local antiseptic agents or antibiotic therapy. If there are any signs of intrauterine infection the pregnancy must be terminated to avert damage from the newborn.

Bacteria↗

[Bacteriologic studies of the amniotic fluid following amniocentesis].

After transabdominal amniocentesis puncture needles and samples of amniotic fluid were microbiologically examined. The antibacterial activity of the amniotic fluid after inoculation of different germs was compared. Positive microbiological results were found in 43 of total 573 puncture needles, but there were germs of the skin flora in 40 cases. Five amniotic fluid samples out of total 424 were contaminated, whereby skin commensals were detected in four samples. The bacteriostatic activity against the examined germs was individually. Complete growth inhibition over 24 hours was observed in cultures with coagulase-negative Staphylococcus, Staph. aureus and E. coli, a less growth inhibition over nearly 10 hours for Pseudomonas aeruginosa. The growth of Strep. faecalis was not suppressed. As result of the frequent observation of skin commensals in amniocentesis puncture needles and amniotic fluid samples clear lines for the performance of the amniocentesis on antiseptic condition basis and for the diagnostic and therapeutic procedure in case of positive microbiological findings were recommended.

Amniocentesis↗