Sex-related dimorphism of the morphofunctional characteristics of the epiphysis in newborn children subjected to hypoxic impairment and asphyxia

In 72 newborn children (37 boys and 35 girls) who suffered from prenatal hypoxia and were born in an asphyxic state, we measured the level of melatonin in the umbilicial blood and observed clinical manifestations of the adaptation/stress syndrome. These data were compared with the results of morphological examination of the epiphyses from 27 stillborns (15 boys and 12 girls) who perished because of heavy prenatal hypoxia. The level of melatonin in the blood of ill newborn girls was much higher than that in boys, and both these indices were about two times higher than those in respective groups of healthy newborn children. At the same time, the pathomorphological examination showed that active epiphyseal cell units in the male fetuses were much more numerous. The results show that the epiphysis plays a significant role in determination of the sex-related dimorphism of the adaptation/stress syndrome in newborn children suffering from hypoxia- and asphyxia-evoked heavy CNS damage. The reasons and consequences of more intensive morphofunctional loading of the epiphyseal system in the male fetuses are discussed.     

A recessive mutation leading to vertebral ankylosis in zebrafish is associated with amino acid alterations in the homologue of the human membrane-associated guanylate kinase DLG3.

We describe the characterization of the zebrafish homologue of the human gene DLG3. The zebrafish dlg3 gene encodes a membrane-associated guanylate kinase containing a single PDZ domain. This gene was cloned using a gene-trap construct inserted in the gene's first intron. The insertion co-segregates with a viable mutation called humpback (hmp), which leads to formation of ankylotic vertebrae in adult fishes. Insertion and mutation have both been mapped to chromosome 12, in a segment which is syntenic with region p12 to q12 of human chromosome 17. The hmp mutant phenotype, however, appears to be due to two point mutations in the guanylate kinase domain rather than to the transgene insertion itself. The results of this study are discussed in the light of the possible function of the guanylate kinase domain.     

Actin participates in the structure of liver intermediate filaments

A dominating protein fraction (p45) having molecular weight of 45000 and pI 5.45 was found in the intermediate filaments pellet obtained from rat liver besides the present cytokeratins. Peptide mapping and radioimmunological assays with antibodies against this protein and muscle actin proved that the p45 protein belongs to the actin group. Immunoelectron microscopy revealed that this protein is located on the liver intermediate filaments. By melting of the cytokeratin complexes in urea it was established that p45 protein is complexed with the low molecular weight cytokeratin.     

Proteinases of small intestine enterocytes of swine. Purification and properties of aspartyl proteinase similar to cathepsin D

A new aspartic proteinase was isolated from porcine intestine mucosa by affinity chromatography on pepstatin-Sepharose 4B and gel filtration on Sephadex G-100. The enzyme was purified 1600-fold and appeared homogeneous upon polyacrylamide gel electrophoresis. The proteinase has a Mr 60 000 +/- 4000 Da. During sodium dodecyl sulfate polyacrylamide gel electrophoresis the enzyme produced a single protein band (Mr 30 000 +/- 3000 Da). Isoelectric focusing revealed that the enzyme has several multiple forms (pI 6.9, 7.5, 8,0). The enzyme is a glycoprotein containing 5.9% of carbohydrates; the mannose to galactose ratio is 1:3. The amino acid composition of the enzyme was studied. The proteinase splits an oxidized insulin B-chain and synthetic substrates. The pH optimum is 3.2. The enzyme is immunologically identical to porcine spleen cathepsin D.     

Selection of HLA compatible donors for patients with HLA antibodies

A strain of 1,507 typised donors enables 15.97 average donors to be selected for a thrombocyte transfusion in one of 75 patients selected at random with HLA antibodies being previously determined (1 to 66 donors per patient). HLA compatible donors were found for 72 patients (97.33 per cent). More than 5 HLA compatible donors could be found for 58 patients. The high number of compatible donors is based on the fact that among 1,507 donors there were 156 HLA homozygotes and 556 donors with 3 HLA-A or B-antigens respectively. Compatibility in the ABO-system was not taken into account.     

Catalytic function of a tyrosyl residue in tryptophanase

Tryptophanase has an essential tyrosyl residue/active site which can be modified by tetranitromethane. Pyridoxal 5'-phosphate can prevent this modification efficiently, whereas pyridoxal 5'-phosphate N-oxide cannot, indicating that the free pyridinium N is required for the interaction of the coenzyme with the tyrosyl residue, probably via a hydrogen bond. The weakened binding of the coenzyme to the modified enzyme was confirmed on gel filtration, the modified enzyme being dissociated from the coenzyme seven-fold faster than the native enzyme. Furthermore, absorption spectral analyses demonstrated that the modified enzyme can catalyze the transaldimination step, but fails to abstract the alpha-H of substrates. The tyrosyl residue, therefore, not only participates in coenzyme binding, but also contributes to alpha-H labilization.     

PHYLOGENETIC ANALYSIS OF THE MALE ONTOGENETIC PROGRAM IN AQUATIC AND TERRESTRIAL MONOCOTYLEDONS

The male program of ontogeny in flowering plants encompasses the events from meiosis of microsporocytes to fertilization. Three main sequences are discussed; the deposition of cell walls, changes in cytoplasmic organelles, and the program of nuclear divisions leading to the formation of two sperm cells and a vegetative cell in each pollen grain. Variations in these ontogenetic sequences are particularly apparent in the monocotyledons, which exhibit diversity in pollen morphology, wall structure, and mode of pollination. The male program of development has been compared in selected terrestrial monocotyledons belonging to the Liliaceae and Gramineae and aquatic members of the Cymodoceaceae, Najadaceae, and Zannichelliaceae. A total of 26 characters from the male program are discussed and then used to construct a cladogram derived only from developmental data for the five species. The polarity of only a few of the character transformations has been determined directly by observation of developmental sequences; most have been interpreted by outgroup analysis.     

Synthesis of intrathecal interferon in systemic lupus erythematosus with neurological complications.

Intrathecal synthesis of interferon in the absence of viral or bacterial infection was detected during the occurrence of neurological complications in two patients with systemic lupus erythematosus. The interferons displayed characteristics similar to those observed in the sera of patients with the disease. No interferon inducing activity was detected in the cerebrospinal fluid or serum of the two patients. These observations support the hypothesis of a localised mechanism of interferon induction in systemic lupus erythematosus which includes the interaction of lymphocytes with damaged tissues.     

Accumulation of pyrophosphate correlates with the increased level of nucleoside triphosphates in Escherichia coli

We measured the concentration of nucleoside triphosphates and inorganic pyrophosphate in Escherichia coli in conditions where nucleotide synthesis or nucleic acid synthesis was inhibited. The inhibitors that brought about an accumulation of some of the four ribonucleoside triphosphates also increased the pyrophosphate level. In a pyrimidine auxotrophic strain uracil starvation led to simultaneous accumulation of ATP and pyrophosphate, and they both rapidly returned to normal level when starvation was relieved. These results indicate the possible involvement of pyrophosphate in the reactions leading to the accumulation of nucleoside triphosphates.