Adjuvant Action of Capsular Polysaccharide of Klebsiella pneumoniae on Antibody Response

The sequence of histological changes in the regional lymph node and other lymphoid organs of mice injected with the capsular polysaccharide of Klebsiella pneumoniae (CPS-K) or bacterial lipopolysaccharide (LPS) was followed. Injection of CPS-K, but not LPS, induced the following characteristic histological changes in the regional lymph node. In the early stage there was a marked decrease in the number of small lymphocytes, accompanied by the appearance of scattered fragmented nuclei and infiltration of polymorphonuclear neutrophilic leukocytes, and in the late stage there was marked proliferation of macrophage-like cells and pyroninophilic cells. Histological changes in the thymus and spleen and changes in cell populations in the bone marrow and peripheral blood after CPS-K injection were essentially the same as after LPS injection. Since CPS-K has a much stronger adjuvant action on antibody response than does LPS, it is suggested that the characteristic histological changes in the regional lymph node after injection of CPS-K are closely related to its extraordinarily strong adjuvant action.     

Involvement of the cholinergic mechanism in DDT and dieldrin action in the insect central nervous system

The effects of DDT and dieldrin on cholinergic neurotransmission were studied using the sixth abdominal ganglion of the cockroach. Spontaneous electrical discharges in the ganglion recorded with an extracellular electrode were augmented by 0.1 mM DDT and 1 microM dieldrin. This stimulating action was partly blocked by 0.5 mM d-tubocurarine and 0.1 mM hemicholinium-3 and disappeared in a high Mg2+-low Ca2+ medium. DDT and dieldrin increased both ACh release and ACh content in the ganglion. These results suggested that DDT and dieldrin stimulate both ACh release and synthesis.     

Involvement of transforming growth factor-alpha secreted by macrophages in metallothionein induction by endotoxin

The mechanism of metallothionein (MT) induction of the liver by endotoxin, which is mediated by a factor secreted by endotoxin-stimulated macrophages, was studied in vitro. MT induction of the liver cells by the endotoxin-stimulated macrophage conditioned medium was inhibited by a monoclonal antiepidermal growth factor (EGF) / transforming growth factor-alpha (TGF-alpha) receptor antibody, which acts as an antagonist of EGF and TGF-alpha. MT was induced by the substance, which was adsorbed by polyclonal antibody to TGF-alpha, but not by a monoclonal antibody to EGF, in the conditioned medium of endotoxin-stimulated macrophages. These results suggest that TGF-alpha secreted by macrophages is involved in MT induction by endotoxin.     

Dietary supplementation of N-3 fatty acids and hydroperoxide levels in rat retinas

Docosahexaenoic acid (DHA) plays an important role in visual and neural development in mammals. In the present study, effect of dietary supplementation with n-3 fatty acids, primarily docosahexaenoic acid (DHA) with high purity, on the fatty acid composition of photoreceptor cells of young rats (fed from 4 weeks) was investigated. DHA in rod outer segment (ROS) membranes was significantly increased in the group of high DHA feeding (9.69% total energy). Other n-3 fatty acids (α-linolenic acid (ALA) and eicosapentaenoic acid (EPA)) included in the diets with DHA (0.95%～5.63% total energy) also significantly increased the proportion of DHA compared with the linoleic acid diet groups. However, the proportions of arachidonic acid (ARA) and other long chain n-6 fatty acids (22:4n6 and 22:5n6) were suppressed in these n-3 fatty acids-fed groups. Phospholipid hydroperoxides in ROS membranes were determined using a highly sensitive analytical technique, chemiluminescence-high performance liquid chromatography (CL-HPLC). There was no increasing tendency in the hydroperoxide levels of ROS membranes containing high content of DHA, and phosphatidylethanolamine hydroperoxide (PEOOH) was much lower than phosphatidylcholine hydroperoxide (PCOOH) under normal light conditions, which implies that DHA supplementation does not much affect the peroxidizability of ROS membranes in vivo. But UV irradiation on separated ROS membranes accelerated the formation of phospholipid hydroperoxides in high DHA feeding rats, and PEOOH was produced more efficiently than PCOOH in vitro.     

Rapid Purification and Crystallization of Thermostable Malate Dehydrogenase Isolated from a Thermophilic Bacterium,Thermus flavus AT 62

A structural study of the water-soluble dextran made by Leuconostoc mesenteroides strain C (NRRL B-1298) was conducted by enzymic degradation and subsequent ¹³C-NMR analysis of the native dextran and its limit dextrins. The α-l,2-debranching enzyme removed almost all of the branched D-glucose residues, and gave a limit dextrin having a much longer sequence of the internal chain length (degree of linearity: n = 24.5 compared with the value of n = 3.3 for the native dextran). The degree of hydrolysis with debranching enzyme corresponded to the content of α-1,2-linkages determined by chemical methods, which suggested that most of the α-l,2-linkages in the dextran B-1298 constituted branch points of a single D-glucose residue. A synergistic increase of susceptibility of the dextran B-1299 was observed by simultaneous use of debranching enzyme and endodex-tranase. ¹³C-NMR spectral analysis indicated the similarity of structure of dextran B-1298 to that of B-1396, rather than that of B-1299. Occurrence of α-l,3-linkages in the limit dextrin was supported by a newly visualized chemical shift at 83.7 ppm.     

Release,Regeneration and Mutant Induction of Pleurotus cornucopiae (‘Tamogitake’) Protoplasts

Both enantiomers of aliphatic and aromatic cyanohydrins were hydrolyzed with the aid of Rhodococcus butanica ATCC 21197 to afford optically active α-hydroxy acids. The usefulness of this reaction is demonstrated by the synthesis of optically pure (R)-4-dodecanolide, a defensive secretion of rove beetles, starting from (R)-2-hydroxydecanenitrile.     

A Japanese child with geleophysic dysplasia caused by a novel mutation of FBN1

Geleophysic dysplasia (GD) is a rare disorder characterized by severe short stature, short hands and feet, limited joint mobility, skin thickening, characteristic facial features (e.g., a “happy” face), and cardiac valvular disorders that often result in an early death. The genes ADAMTSL2 (a disintegrin-like and metalloprotease with thrombospondin type 1 motif-like 2) and FBN1 (fibrillin 1) were recently identified as causative genes for GD. Here, we describe a 10-year-old Japanese female with GD who was born to non-consanguineous parents. At the age of 11 months, she was referred to our hospital because of very short stature for her age (− 4.4 standard deviations of the age-matched value) and a “happy” face with full cheeks, a shortened nose, hypertelorism, and a long and flat philtrum, characteristic of GD. Her hands and feet were small, her skin was thickened, and her joint mobility was generally limited. She had cardiac valvular disorders and history of recurrent respiratory failure. Mutation analysis revealed no abnormalities in ADAMTSL2. However, analysis of FBN1 revealed a novel heterozygous mutation (c.5161T > T/G) in exon 41, which encodes transforming growth factor-β-binding protein-like domain 5 (TB5). GD is an extremely rare disorder and, to our knowledge, only one case of GD with an FBN1 mutation has been reported in Japan. Similar to the previously reported cases of GD, the mutation in the current patient was located in the TB5 domain, which suggests that abnormalities in this domain of FBN1 are responsible for GD.     

Hybrid Oligomer of Cyclonucleotides and Deoxynucleotides. A High Anti Left-handed Double Helical DNA Structure

Abstract

It has been shown by us that oligonucleotides containing cyclonucleosides with a high anti glycosidic conformation take left-handed, single and double helical structures (S. Uesugi, J. Yano, E. Yano and M. Ikehara, J. Am. Chem. Soc. 99, 2313 (1977) and references therein). In order to see whether DNA can adopt the high anti left-handed double helical structure or not, a self-complementary hexanucleotide containing 6,2′-O-cyclocytidine (C^○), 8,2′-O-cyclo- guanosine (G^○), deoxycytidine and deoxyguanosine, C^○G^{○dCdGC ○}G^○, was synthesized. Corresponding hexanucleotide containing only cyclonucleosides, C^○G^○C^○G^○C^○G^○, was also synthesized. Their conformation was examined by UV, CD and ¹H NMR spectroscopy. C^○G^○C^○G^○C^○G^○ forms an unusually stable, left-handed duplex. Imino proton NMR spectra and the results of nuclear Overhauser effect experiments strongly suggest that C^○G^○dCdGC^○G^○ take a left-handed double helical structure where the deoxynucleoside residues are involved in hydrogen bonding and take a high anti glycosidic conformation. Thus it is revealed that DNA could form a high anti, left-handed double helix which is different from that of Z-DNA under some constrained conditions.