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Biomedical subjects

M Noda

Publications and source records attributed to M Noda.

At least 649 records · Page 36Linked to original sources
PubMed1981

Structure of the baboon endogenous virus genome: nucleotide sequences of the long terminal repeat.

The entire nucleotide sequence of the long terminal repeat (LTR) of baboon endogenous virus (BaEV) M7 was determined, which consisted of 554 base pairs (bp). At both ends of the LTR, 13 bp sequences, AAATGAAAAGTAA and TGATTCTAACATC, were detected to be inverted repeats. The structure with these inverted repeats resembles those of other retroviruses and transposable elements. a Hogness box, TATAAAA, and a putative poly(A)-addition signal, AGTAAA, were present within the right-hand half of the LTR, where the initiation and termination of the viral RNA synthesis seems to occur in the integrated BaEV genome. The primer-binding site of at least 14 bp long was found just outside of the LTR where the strong stop DNA started, and the primer for reverse transcription in BaEV seemed to be tRNAPro. Several structural features are commonly detected in the LTRs of BaEV and other retroviruses. Our studies suggest that BaEV has evolved from a common ancestor with other mammalian type C viruses. Close relationships between BaEV and a feline endogenous virus, RD114, are demonstrated.

Cloning, Molecular↗
PubMed1981

Structure of the baboon endogenous virus genome: cloning of circular virus DNA in bacteriophage lambda.

Linear, small and large circular forms of unintegrated viral DNAs were detected in Hirt supernatant fraction of human cultured cells infected with baboon endogenous virus M7. The circular M7 DNAs were cloned in bacteriophage lambda, Charon 28. Seventeen independent clones were isolated and analyzed by restriction endonuclease mapping. Nine clones were carrying a viral sequence of 8.6 kilobase pairs (kb) with two tandem repeats of 0.6 kb, which correspond to the large circular form of the unintegrated M7 DNA. Eight other clones had the viral insert of 8.0 kb, i. e., the small circular form, and were deleted one of the repeated sequences. The repeated sequences correspond to the long terminal repeats of 0.6 kb, located at both ends of the linear M7 DNA of 8.6 kb. One of the recombinants of the large circular M7 DNA had an inversion of 2.5 kb. One end of the inverted sequence was near the terminus of the long terminal repeats and the other in the gag gene region. The inversion seems to be occurred by integration of a viral DNA within itself during early periods of infection. The mechanism of the processes leading to integration is discussed from the structure of these unintegrated M7 DNAs as the precursors.

Bacteriophage lambda↗
PubMed1981

Studies on proteinases from the digestive organs of sardine. I. Purification and characterization of three alkaline proteinases from the pyloric caeca.

Three alkaline proteinases designated I, II and III are found in the pyloric caeca of sardine and isolated by (NH4)2SO4 fractionation, DEAE-cellulose chromatography and gel filtration on Sephadex G-100. The final preparations were judged homogeneous by multiple criteria. The molecular weights of the enzymes I, II and III were determined by the sedimentation equilibrium method to be 22 900, 28 700 and 27 000, respectively. The isoelectric points were 5.45, 5.30 and 4.85, and the sedimentation coefficients (S0 20, w) were 2.91, 3.06 and 2.94, respectively. Enzymes II and III had similar amino acid compositions which were different from that of enzyme I, especially in the content of lysine, valine and tyrosine. All the enzymes belonged to a group of serine proteases. Enzymes II and III were found to be an anionic alpha-chymotrypsin-like enzymme and an anionic trypsin-like enzyme, respectively. Although these fish enzymes had properties in common with those of bovine pancreatic cationic trypsin and chymotrypsin, they are distinctly different in their optimum pH, pH stability, net charge and immunological properties.

Amino Acids↗
PubMed1981

Studies on proteinases from the digestive organs of sardine. II. Purification and characterization of two acid proteinases from the stomach.

Two fish acid proteinases designated acid proteinase I and II were found and isolated by (NH4)2SO4 fractionation, CM-cellulose chromatography and gel filtration on Sephadex G-100. The final preparations were judged nearly homogeneous by multiple criteria. The molecular criteria. The molecular weights of the enzymes I and II were determined by the sedimentation equilibrium method to be 37 000 and 33 400, respectively. The sedimentation coefficients (S0 20, w) were 3.06 and 3.09, respectively. Enzymes I and II contained similar amino acid composition except for the contents of histidine, arginine, threonine, serine and proline. Enzymes I and II differed from each other in optimal pH and stability at pH 7. Each enzyme could scarcely hydrolyze a synthetic pepsin substrate, N-acetyl-L-phenylalanyl-3,5-diiodo-L-tyrosine (APDT). Both of the enzymes were inhibited by acid proteinase specific reagents: pepstatin, diazoacetyl-DL-norleucine methyl ester (DAN), 1,2-epoxy-3-(p-nitrophenoxy) propane (EPNP) and p-bromophenacyl bromide. These results indicate fish enzymes are similar to mammalian pepsin and microbial acid proteinases in their active site structure having two different carboxyl groups, although they differ in regard to a number of molecular and enzymatic properties.

Amino Acids↗
PubMed1981

Isolation and characterization of the bovine corticotropin/beta-lipotropin precursor gene.

The entire bovine corticotropin/beta-lipotropin precursor gene has been isolated as a set of overlapping genomic DNA fragments which extend over a length of approximately 17000 base pairs. Restriction mapping of the cloned DNA fragments and nucleotide sequence analysis of the whole mRNA-coding segments and their surrounding regions have established that the corticotropin/beta-lipotropin precursor gene is approximately 7300-base-pairs long and contains two intervening sequences; one with an approximate length of 4000 base pairs is located within the segment encoding the 5'-untranslated region of the mRNA, and the other with an approximate length of 220 base pairs interrupts the protein-coding sequence near the signal peptide region. Sequence analysis of more than 200 base pairs preceding the proximal end of the corticotropin/beta-lipotropin precursor gene has revealed a 'Hogness box' and a variant of the model sequence d(G-G-TC-C-A-A-T-C-T) as well as palindrome structures as observed in other eukaryotic genes. Furthermore, some sequence similarities in the 5'-flanking region are found between the corticotropin/beta-lipotropin precursor gene and the mouse alpha-globin and beta-globin genes, all of which are negatively regulated by glucocorticoids. At least four homologous repetitive sequences are distributed at 3000-5000-base-pair distances in the corticotropin/beta-lipotropin precursor gene region; two such sequences are located in the 5'-flanking region, and one within each intervening sequence. Blot hybridization analysis of bovine pituitary nuclear RNA has indicated that the entire corticotropin/beta-lipotropin precursor gene is transcribed into a primary hnRNA product, which is then spliced to form the mature mRNA.

Adrenocorticotropic Hormone↗
PubMed1981

Mode of action of staphylococcal leukocidin: relationship between binding of 125I-labeled S and F components of leukocidin to rabbit polymorphonuclear leukocytes and leukocidin activity.

The binding of (125)I-labeled S component to rabbit polymorphonuclear leukocytes was found to be concentration dependent and saturable at 37 degrees C. Scatchard analysis of the binding curve gave a straight line, indicating that S component binds to a single population of sites. The dissociation constant, K(D), derived from the Scatchard plot was 5.57 x 10(-9) M, and the number of binding sites per leukocyte was calculated to be approximately 5,300. Unlabeled S component (10(-8) M) or subunit B of cholera toxin (10(-7) M) readily competed with (125)I-labeled S component binding, and the labeled S component, preincubated with ganglioside G(M1) at equimolar proportions for 5 min, lost the binding capacity to the leukocyte membranes. The binding number of (125)I-labeled F component to leukocidin-sensitive cells, such as rabbit polymorphonuclear leukocytes and the established human myelocytic leukemia cells, in the absence and in the presence of the unlabeled S component (2.1 nM), was calculated to be 50 and 1,300 molecules per cell, respectively. This increased binding of the labeled F component was time and temperature dependent. The binding number of labeled F component to other cell types comparatively insensitive to leukocidin, such as erythrocytes, adipocytes, intestinal cells, and HeLa cells, was calculated to be less than 50 molecules per cell in spite of the sufficient amount of unlabeled S component bound to their cells. These observations are consistent with the view that in rabbit leukocyte the S component, preferentially bound to the cell surface at 5,300 molecules per cell, contributes to enhance the F component binding up to about 1,300 molecules per cell and may thus play a role of synergistic action of both leukocidin components on the cell membranes in the leukocytolysis.

Adipose Tissue↗
PubMed1981

[CT in normal pressure hydrocephalus--correlation between CT and clinical response to shunting (author's transl)].

CT scans were obtained on 33 patients (age 73y. to 31y.) with the diagnosis of normal pressure hydrocephalus. In each case, the diagnosis was made on the basis of the symptoms, CT and cisternographic findings. Underlying diseases of normal pressure hydrocephalus are ruptured aneurysms (21 cases), arteriovenous malformations (2 cases), head trauma (1 case), cerebrovascular accidents (1 case) and idiopathy (8 cases). Sixteen of 33 patients showed marked improvement, five, moderate or minimal improvement, and twelve, no change. The results were compared with CT findings and clinical response to shunting. CT findings were classified into five types, bases on the degree of periventricular hypodensity (P.V.H.), the extent of brain damage by underlying diseases, and the degree of cortical atrophy. In 17 cases of type (I), CT shows the presence of P.V.H. with or without minimal frontal lobe damage and no cortical atrophy. The good surgical improvements were achieved in all cases of type (I) by shunting. In 4 cases of type (II), CT shows the presence of P.V.H. and severe brain damage without cortical atrophy. The fair clinical improvements were achieved in 2 cases (50%) by shunting. In one case of type (III), CT shows the absence of P.V.H. without brain damage nor cortical atrophy. No clinical improvement was obtained by shunting in this type. In 9 cases of type (IV) with mild cortical atrophy, the fair clinical improvement was achieved in two cases (22%) and no improvement in 7 cases. In 2 cases of type (V) with moderate or marked cortical atrophy, no clinical improvement was obtained by shunting. In conclusion, it appeared from the present study that there was a good correlation between the result of shunting and the type of CT, and clinical response to shunting operation might be predicted by classification of CT findings.

Adult↗
PubMed1981

[Normal pressure hydrocephalus (NPH) following subarachnoid hemorrhage (SAH)-clinical consideration of CT and development of hydrocephalus after SAH (author's transl)].

CT scans were used to evaluate the development of the hydrocephalus, periventricular hypodensity (PVH) and the degree of the brain damage on 33 patients with the normal pressure hydrocephalus (NPH), following the subarachnoid hemorrhage (SAH), and the following conclusion can be drawn from our study. 1) NPH occurs in 33 cases out of 156 cases of subarachnoid hemorrhage (21%), and there was a relatively high incidence of normal pressure hydrocephalus following rupture of the anterior communicating artery aneurysm. 2) Factors causing NPH may be the arterial vasospasms and subarachnoid blood clot of the basal cistern verified by CT. 3) According to the repeated CT and lumbar tap after SAH, PVH, and, hydrocephalus usually become apparent around 7-10 days and most prominent around 3-4 weeks after SAH except for acute hydrocephalus appeared immediately after severe SAH. 4) The results were compared with CT findings and clinical response to shunting. The clinical improvements were achieved in cases (85%), in which CT showed PVH, small brain damage in the frontal lobe due to vasospasms or intracerebral hematoma, and no cortical atrophy. 5) Repeated CT can give better informations on the development of hydrocephalus in cases of SAH and can provide the indication for a shunt.

Adult↗
PubMed1980

Crystallization and properties of staphylococcal leukocidin.

Two components (F and S) of leukocidin were isolated and purified from broth culture of V8 strain of Staphylococcus aureus. There was loss of leukocidin activity during the separation, which was regained by mixing the components. Each component was apparently homogeneous by several criteria. The F and S components were crystallized (by salting out with saturated (NH4)2SO4 at pH 7.0) in the form of square plates and very fine needles, respectively, and the molecular weights of the components were approx. 32 000 and 31 000, respectively. The isoelectric points of the F and S components were pH 9.08 and 9.39, respectively. No detectable half-cystine and free sulfhydryl groups were found in either component. Amino-terminal amino acid analysis of both components showed a single alanine residue. The F and S components of leukocidin acted synergistically on granulocytes from rabbit peripheral blood and a minimum lethal dose of 0.5 ng of each component destroyed all granulocytes at a concentration of 10(6) cells/20 microliter.

Amino Acids↗
PubMed1980

The protein-coding sequence of the bovine ACTH-beta-LPH precursor gene is split near the signal peptide region.

The pituitary hormones corticotropin (ACTH) and beta-lipotropin (beta-LPH) are formed from a large common precursor. Recently, we have elucidated the whole primary structure of the bovine ACTH-beta-LPH precursor (designated alternatively as preproopiocortin) by determining the nucleotide sequence of cloned DNA complementary to the mRNA coding for the precursor protein. The amino acid sequence assigned has disclosed a characteristic repetitive structure of the ACTH-beta-LPH precursor. The repetitive units of the precursor protein each contain a melanotropin (MSH) sequence (alpha-, beta- or gamma-MSH) as well as other peptide components such as beta-endorphin and corticotropin-like intermediate lobe peptide (CLIP). The repetitive units as well as their peptide components are each bounded by paired basic amino acid residues, which apparently represent the sites of proteolytic processing. Several studies have confirmed the translational initiation site and protein structure assigned (see also ref. 11 and refs therein). In view of the recent knowledge about the organization of eukaryotic genes (see refs 12, 13 for reviews), it would be of particular interest to investigate the relationship between the repetitive structure of the ACTH-beta-LPH precursor containing different functional components and the arrangement of the protein-coding sequence in its gene. We have now isolated and characterized bovine genomic DNA fragments encoding this precursor protein and have demonstrated that the protein sequence is encoded by two non-consecutive DNA segments. An intron (intervening sequence) of approximately 2.2 kilobase pairs separates the smaller exon (mRNA-coding sequence), which contains the gene sequence encoding the signal peptide, from the larger exon, which contains the gene sequence for most of the protein structure, including the known biologically active component peptides.

Adrenocorticotropic Hormone↗
PubMed1980

Ultrastructural study of granular cell ameloblastoma.

A granular cell ameloblastoma occurring in the anterior mandible of a 49-year-old woman has been studied both histologically and ultrastructurally. Histologically the tumor in this case showed a mixed type of follicular, granulal cell, and acanthomatous type of ameloblastoma. Many granular cells seemed to gather around the periphery of each tumor island. Electron-microscopically the cytoplasmic granules were measured as approximately 0.6 mu in diameter, and were surrounded by limiting membrane. Most of these granules revealed high electron density and their contents showed various patterns--osmiophilic homogeneous, fingerprint, and small particles--and were identified as lysosomes. However, no enamel matrix precursor was identified in either lysosome or cytoplasm. All the granular cells showed regular nuclei and no degeneration. Though lysosomes might play a role of autophagy and of remodeling the cytoplasm, its presence seems to have an active function in tumor cells, as opposed to the aging or degenerating function.

Ameloblastoma↗
PubMed1980

Fixation and inactivation of staphylococcal leukocidin by phosphatidylcholine and ganglioside GM1 in rabbit polymorphonuclear leukocytes.

Staphylococcal leukocidin is resolved by chromatography on carboxymethyl cellulose columns into two components, which are designated F (fast) and S (slow). Fixation and inactivation of both components were studied as follows. (i) Leukocidin activity was confined to the first 10 min of intoxication, and the maximal effect resulted from treating 10(6) rabbit peripheral polymorphonuclear leukocytes per 20 mul with 0.5 ng of each component of leukocidin. The S component was more responsible for the interaction with the leukocytes than the F component. (ii) The F component was inactivated by phosphatidylcholine at concentrations which corresponded to molar proportions of 1:1 and bound to [(14)C]phosphatidylcholine at equimolar proportions. (iii) The S component was inactivated by ganglioside G(M1) at 1:1 molar proportions, but not by any of the related glycolipids. Ganglioside G(M1) also was precipitated with the S component by a gel diffusion technique. Subunit B of cholera toxin competitively inhibited the binding of the S component to rabbit leukocyte membranes. This indicates that ganglioside G(M1) may resemble or be part of the receptor site for the S component.

Animals↗
PubMed1979

Mutagenic activity of selenium compounds.

The mutagenicities of selenate (SeO2/4-) and selenite (SeO2/3-) were determined by two bacterial assay systems: Kada's rec-assay and Ames's Salmonella test. In both assays, these compounds were found to be weak mutagens. In the Salmonella test, selenate (0.05 revertants/nmole) and selenite (0.2 revertants/nmole) gave rise to base-pair substitution.

Bacillus subtilis↗
PubMed1978

18p-Mosaicism: case report and review.

The case of a 5-month-old male infant with 18p- mosaic, who has intractable seizures and severe ophthalmological abnormalities in addition to many clinical manifestations usually described in the 18p- syndrome, is reported. The proportions of abnormal cells are 7-8% in blood and 55% in skin. About 35% of the short arm of chromosome 18 is deleted. to our knowledge the present report is the fifth one of 18p-mosaic. The main interest of this case resides in the fact that it shows a serious clinical picture despite the low proportion of abnormal cells in blood and the small degree of deletion of the short arm of chromosome 18.

Chromosome Deletion↗