[Experience with percutaneous endoscopic gastrostomy in the nutrition of a patient with 3rd and 4th degree facial burns]. / Percutan endoszkópos gastrostomán át táplált III-IV. fokú arcégett beteg kezelésével nyert tapasztalataink.

Recovery after thermal injury depends in great proportion on nutrition. A major problem is accounted in patients with facial burn, because they can not be nourished per vias naturales. Eliminating disadvantages of parenteral nutrition, but utilizing the advantages of enteral nutrition, we have tried a new method of treatment in a patient whose case is presented. On the second day after injury a percutaneous endoscopic gastrostomy was made. On the 7th day after injury and on the 4th day from the beginning of enteral nutrition complete intake of food and liquid was assured through the percutaneous endoscopic gastrostoma. We had no complication related to the gastrostoma. Nutrition through the percutaneous endoscopic gastrostoma at our patient provided a "natural" route to assure liquid, electrolite and energy balance, prevented atrophy of intestinal mucosa and its metabolic and immunologic complications. With the use of percutaneous endoscopic gastrostoma the possible complications of central line catheter were omitted. Our opinion is that percutaneous endoscopic gastrostomy is a safe and effective method for the clinical nutrition of burned patients.

The gene encoding the elongation factor P protein is essential for viability and is required for protein synthesis.

Elongation factor P (EFP) is a protein that stimulates the peptidyltransferase activity of fully assembled 70 S prokaryotic ribosomes and enhances the synthesis of certain dipeptides initiated by N-formylmethionine. This reaction appears conserved throughout species and is promoted in eukaryotic cells by a homologous protein, eIF5A. Here we ask whether the Escherichia coli gene encoding EFP is essential for cell viability. A kanamycin resistance (KanR) gene was inserted near the N-terminal end of the efp gene and was cloned into a plasmid, pMAK705, that has a temperature-sensitive origin of replication. After transformation into a recA+ E. coli strain, temperature-sensitive mutants were isolated, and their chromosomal DNA was sequenced. Mutants containing the efp-KanR gene in the chromosome grew at 33 degrees C only in the presence of the wild-type copy of the efp gene in the pMAK705 plasmid and were unable to grow at 44 degrees C. Incorporation of various isotopes in vivo suggests that translation is impaired in the efp mutant at 44 degrees C. At 44 degrees C, mutant cells are severely defective in peptide-bond formation. We conclude that the efp gene is essential for cell viability and is required for protein synthesis.

Structure of the chicken link protein gene: exons correlate with the protein domains.

The structure of the chicken link protein gene has been determined from a series of genomic clones that cover the entire coding region as well as the complete 3'-untranslated region and a small portion of the 5'-untranslated region. The gene is greater than 80 kilobase pairs long and is present in a single copy in the chicken genome. The link protein gene contains at least five exons with four encoding the entire protein. The domain of link protein that has homologies with immunoglobulin-like proteins and the tandemly repeated hyaluronic acid binding domains are each encoded by separate exons. The exon-intron structure indicates that the link protein gene may have arisen by exon duplication and exon shuffling.

Inactivation of pig muscle 3-phosphoglycerate kinase by thiol modification depends on reagent size.

Two thiol groups (out of the total seven) of pig muscle 3-phosphoglycerate kinase can be alkylated in 0.1 M Tris/Hcl buffer, pH 7.5, at 20 degrees C either with methyl iodide or with iodoacetamide in a second-order reaction with rate constants 0.05 +/- 0.02 M-1S-1 and 0.23 +/- 0.05 M-1S-1 respectively. The slow reaction of the remaining five thiols with Ellman's reagent (Nbs2), which requires the unfolding of the protein, is not affected by the nature of the alkylating reagent. While methylation of the two reactive thiols does not affect either the specific activity of the enzyme or the Km values of the substrates, carboxamidomethylation is accompanied by the loss of enzymic activity. Both the methylated and the carboxamidomethylated enzymes bind 3-phosphoglycerate or MgATP practically with the same binding constants as the native enzyme, as detected by fluorimetric titration of enzymes complexed with 1-anilinonaphthalenesulfonate (ANS). Thus, inactivation during carboxamidomethylation cannot be due to changes in the substrate-binding ability of the enzyme. The substrate-caused changes in the fluorescence emission spectrum of ANS bound to the carboxamidomethylated enzyme are different from the changes observed with the native enzyme. The fluorescence properties of the methylated enzyme do not differ from those of the native enzyme. These differences may reflect the different mode of substrate binding to the carboxamidomethylated enzyme as compared to the native or the methylated one. Thus, the special steric requirements of the enzymic reaction are possibly not fulfilled after carboxamidomethylation. The presence of the equilibrium mixture of substrates lessens the reactivity of the fast-reacting thiols towards both alkylating agents, a finding that indicates the effects of substrates on the local conformation around these groups.