Bilateral pneumonia and inappropriate secretion of antidiuretic hormone in a premature infant.

A 6-week-old infant born prematurely had severe hyponatremia and other features of the syndrome of inappropriate secretion of antidiuretic hormone (SIADH). This disturbance was believed to be secondary to extensive bilateral pneumonia with collapse of the right upper lobe. Although this association has been recognized in adults, this is the first report of its occurrence in an infant. SIADH must be considered in the differential diagnosis of hyponatremia in association with pneumonia in an infant.     

Klebsiella pneumonia with pneumatocele formation in a newborn infant

The case of a premature infant with bacteriologically proved klebsiella pneumonia in the first week of life is reported. The clinical course was complicated by the early formation of pneumatoceles and subsequent recurrent pneumothoraces. Treatment consisted of antibiotic therapy and chest tube drainage. Satisfactory clinical recovery, growth and psychomotor development were noted at 1 year of age, despite the persistence of a pneumatocele in the right lung.     

Photosynthetic activity of diimidoester-modified cells,permeaplasts, and cell-free membrane fragments of the blue-green alga Anacystis nidulans

On treating the blue-green alga Anacystis nidulans with dimethylsuberimidate up to 70% of the free NH₂ of the photosynthetic membrane is amidinated, and presumably inter- and intramolecular cross-links are established in the membrane proteins. Amidination destroys the ability of A. nidulans to photoreduce HCO₃^? but leaves the photochemical activities of Photosystems II and I nearly intact. With added electron acceptors, photosynthetic O₂ evolution can be demonstrated both with permeable cells (permeaplasts) prepared by digestion of the cell wall of dimethylsuberimidate-reacted A. nidulans with lysozyme, as well as with heavy membrane particles (36 000 × g) prepared from dimethylsuberimidate-reacted cells.Permeaplasts prepared from dimethylsuberimidate-reacted cells resist damage in hypoosmotic medium, whereas those prepared from unreacted cells are induced to release C-phycocyanin. On the other hand, the former are inactivated more easily by heat stress than the latter. On this basis, it is concluded that cross-linking with dimethylsuberimidate confers functional instability to photosynthetic membranes.     

A new synthesis of the tripeptide Gly-His-Lys with antimicrobial activity

Summary A new solid phase synthesis of the growth-modulating tripeptide Gly-His-Lys is described. 2-Chlorotrityl chloride resin and 9-fluorenylmethoxycarbonyl-(Fmoc), 4-methyltrityl-(Mtt) protecting groups were used. The synthetic tripeptide was tested for its activity against bacteria, yeast and fungi. The in vitro effect of the tripeptide on DNA, RNA and protein synthesis was studied as well.