Clinical significance of adrenal computed tomography in Addison's disease.

Adrenal computed tomographic (CT) scanning was conducted in twelve patients with Addison's disease during the clinical course. In tuberculous Addison's disease (n = 8), three of four patients examined during the first two years after disease onset had bilaterally enlarged adrenals, while one of four had a unilaterally enlarged one. At least one adrenal gland was enlarged after onset in all six patients examined during the first four years. Thereafter, the adrenal glands may atrophy bilaterally, in contrast to adrenal glands in idiopathic Addison's disease, which atrophy bilaterally from disease onset (n = 2). Adrenal calcification was a less sensitive clue in tracing pathogenesis, i.e., adrenal calcification was observed in five of eight patients with tuberculous Addison's disease, but not in idiopathic patients. Thus, adrenal CT scanning could show the etiology of Addison's disease (infection or autoimmunity) and the phase of Addison's disease secondary to tuberculosis, which may be clinically important for initiating antituberculous treatment.     

Immunohistochemical and immunoelectron microscopic analyses of alpha-amylase isozymes in human intrahepatic biliary epithelium and hepatocytes.

The expression and localization of the pancreatic and salivary isozymes of alpha-amylase in the intrahepatic biliary epithelium and hepatocytes were examined by the immunohistochemical method with polyclonal and monoclonal antibodies in 45 normal autopsied human livers. Immunoelectron microscopic studies with the protein A-gold method were performed with the monoclonal antibodies (MAb) on seven of the livers. The intrahepatic biliary system was divided into large ducts, septal ducts, interlobular ducts, bile ductules, and peribiliary glands. Immunohistochemically, pancreatic isozyme was observed in the supranuclear cytoplasm of the epithelium of large ducts, septal ducts, and peribiliary glands in almost all livers. Interlobular ducts expressed pancreatic isozyme in only four (9%) livers. Bile ductules and hepatocytes were negative for pancreatic isozyme in all cases. Expression of salivary isozyme was observed in the supranuclear cytoplasm of the epithelium of large ducts, septal ducts, interlobular ducts, bile ductules, and peribiliary glands in almost all livers, although the expression in interlobular ducts and bile ductules was weak. Hepatocytes were weakly positive for salivary isozyme. Immunoelectron microscopy revealed that both pancreatic and salivary isozymes were located in the supranuclear cytoplasm of the epithelium of large ducts, septal ducts, and peribiliary glands, and that hepatocytes had no pancreatic isozyme but contained salivary isozyme. These data suggest that pancreatic and salivary isozymes of alpha-amylase are produced by the intrahepatic biliary epithelium and secreted into intrahepatic biliary lumens, and that they may play an important role in the physiology of the intrahepatic biliary tree and hepatic bile. It is also suggested that hepatocytes produce a small amount of salivary alpha-amylase that may be secreted into the biliary tree.     

Enhanced growth of the red algaPorphyra yezoensis Ueda in high CO2 concentrations

Leafy thalli of the red algaPorphyra yezoensis Ueda, initiated from conchospores released from free-living conchocelis, were cultured using aeration with high CO₂. It was found that the higher the CO₂ concentration, the faster the growth of the thalli. Aeration with elevated CO₂ lowered pH in dark, but raised pH remarkably in light with the thalli, because the photosynthetic conversion of HCO ₃ ^? to OH^? and CO₂ proceeded much faster than the dissociation of hydrated CO₂ releasing H⁺. Photosynthesis of the alga was found to be enhanced in the seawater of elevated dissolved inorganic carbon (DIC, CO₂ + HCO ₃ ^? + CO ₃ ^? ). It is concluded that the increased pH in the light resulted in the increase of DIC in the culture media, thus enhancing photosynthesis and growth. The relevance of the results to removal of atmospheric CO₂ by marine algae is discussed.     

Translocation of colicin E1 through cytoplasmic membrane of Escherichia coli

The product of the malE—lacZ gene fusion was reported to compete with some proteins including outer membrane lipoprotein in the protein translocation across the Echerichia coli membrane. The fusion product also inhibited colicin E1 export. Furthermore, globomycin, which accumulated prolipoprotein in the membrane, inhibited the translocation of colicin E1 in the wild-type cells, but not in lipoprotein-negative mutant cells. Since colicin E1 contains the internal signal-like sequence [Proc. Natl. Acad. Sci. USA (1982) 79, 2827–2831], these results suggest that colicin E1 is exported by the aid of this sequence at a common site for maltose-binding protein and lipoprotein translocation.     

Degradation of Xyloglucan by Wall-bound Enzymes from Soybean Tissue I. Occurrence of Xyloglucan-degrading Enzymes in Soybean Cell Wall

An enzyme preparation that catalyzes the degradation of xyloglucanwas obtained by extraction of the cell walls of soybean hypocotylswith a buffer containing 1.0 M NaCl. The enzyme preparationwas shown to catalyze two-step degradation of xyloglucan. Thepolysaccharide was first degraded into comparatively large fragments,which were then further degraded into monosaccharides. In orderto elucidate the mode of degradation of the xyloglucan duringcell growth, the activities of xyloglucandegrading enzymes ofsoybean-hypocotyl segments were assayed at different stagesof elongation. The total activities of the degrading enzymeswere lower in the elongating regions than in the non-elongatingregions. However, high levels of endo-ß-l,4-glucanasewere found in the elongating regions. These results suggestthat xyloglucan is hydrolyzed by endo-ß-1,4-glucanaseinto comparatively large fragments at the initial stage of growthand the resulting fragments are further degraded into monosaccharidesduring cell elongation. (Received May 20, 1981; Accepted August 8, 1981)     

Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide by 3-chloro-D-alanine hydrogen chloride-lyase (deaminating) of Pseudomonasputida

Synthesis of D-cysteine from 3-chloro-D-alanine and hydrogen sulfide is catalyzed by highly purified 3-chloro-D-alanine hydrogen chloride-lyase from $\text{Pseudomonas}\text{putida}$. The synthetic reaction proceeds optimally at pH 8.5, as a function of enzyme concentration and incubation time. The enzymatically synthesized D-cysteine was isolated from the large scale reaction mixture and identified by physicochemical means.     

Catalytic activity and arrangement of subunit polypeptides in rat liver cytochrome c oxidase as studied by proteolysis

Cytochrome c oxidase from rat liver was incubated with various proteinases of different specificities and the enzymic activity was measured after various incubation times. A loss of catalytic activity was found after digestion with proteinase K, aminopeptidase M and a mitochondrial proteinase from rat liver. In each case the decrease in enzymic activity was compared with the changes in intensities of the polypeptide pattern obtained after sodium dodecyl sulfate polyacrylamide gel electrophoresis. The susceptibilities of the subunit polypeptides of the soluble cytochrome c oxidase to proteinases were very different. Whereas subunit I was most susceptible, subunits V–VII were rather resistant to degradation. From the relative inaccessibility of subunits V–VII to proteinases it is likely that these polypeptides are buried in the interior of the enzyme complex.