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Biomedical subjects

K Kitajima

Publications and source records attributed to K Kitajima.

At least 199 records · Page 11Linked to original sources

Isolation and characterization of a novel type of sialoglycoproteins (hyosophorin) from the eggs of medaka, Oryzias latipes: nonapeptide with a large N-linked glycan chain as a tandem repeat unit.

We found a novel type of sialoglycoprotein (SGP) with apparent molecular mass ranging from 15,000 to 100,000 Da in the unfertilized eggs of the medaka fish, Oryzias latipes. From fertilized eggs we isolated the corresponding sialoglycopeptides of apparent molecular weight 7000. The amino acid and carbohydrate compositions of these glycoproteins and glycopeptides are very similar, if not identical, and they contain 90%, by weight, of carbohydrate, the predominant sugars being Gal, GlcNAc, and NeuAc. The chemical and physical data indicate that 15- to 100-kDa SGPs are made up of tandem repeat structures whose repeating unit is 7-kDa sialoglycopeptide, and, upon fertilization, higher molecular weight SGPs undergo proteolytic depolymerization to the least structural unit, 7-kDa sialoglycopeptide. As is the case with polysialoglycoproteins (PSGP) found in salmonid fish eggs, a novel family of sialoglycoproteins has been proven to be a major component of cortical alveoli of medaka eggs, namely, hyosophorin. However, we found that they differ markedly from PSGPs (salmonid fish egg hyosophorins) in terms of the carbohydrate composition. The chemical composition and the results of Smith degradation indicate that SGP contains one large N-linked glycan chain per repeat unit. We have determined the amino acid sequence of 7-kDa sialoglycopeptide: Asp-Ala-Ala-Ser-Asn*-Gln-Thr-Val-Ser, where * indicates the asparagine residue to which a large glycan chain consisting of Fuc2Man3Gal15GlcNac9NeuAc6 is attached. The direct experimental evidence for the presence of a polyprotein structure suggests that the covalent nature of the higher molecular weight SGPs should be expressed as [Asp-Ala-Ala-Ser-Asn*-Gln-Thr-Val-Ser]N, where N = 2 to 14 but for the major fraction N = 12.

Amino Acid Sequence↗

Inter- and intracellular luminal formation in porcine thyroid tissues cultured in a collagen substrate.

Porcine thyroid epithelial cells, isolated and cultured on a type I collagen substrate, formed a monolayered sheet. When the apical surface of the monolayer was further covered with the same collagen substrate, the epithelial cells migrated and formed intercellular follicular lumen-like structures. In addition, a true intracellular follicular lumen sometimes appeared, especially in cells of the monolayer region. It was proved by serial sections that the intracellular follicular lumina, 1-5 microns in diameter, lined by rather long microvilli and stained for PAS, had no openings to the extracellular space. The intracellular lumina are presumed to fuse with each other to form an intercellular follicular lumen, or fuse with the performed intercellular follicular lumen. Auto-radiographic studies using 125I revealed that iodination of thyroglobulin takes place in the peripheral region of both intracellular and intercellular follicular lumina.

Animals↗

[Immunohistochemical study of keratin-positive cells in human prostatic cancer].

The purpose of this study is to demonstrate the localization and distribution of keratin-positive cells (KPC) in the various pathological types of prostatic cancer, and to investigate the correlation between the basal cell and KPC. The localization of keratin was immunohistochemically investigated in 20 benign prostatic hyperplasia (BPH) and 33 human prostatic adenocarcinomas by the indirect immunoperoxidase technique, using anti human keratin rabbit serum on frozen sections. In BPH, strongly positive staining for keratin was detected in the cytoplasm of basal cells. Glandular epithelial cells were positive. In the cancer sections, no KPC was observed in all 6 cases of the large acinar type, all 10 cases of the small acinar type and all 12 cases of the column and cord type. On the other hand, KPC remained around the cancer cell populations in all 10 cases of the cribriform type. In the fused gland type, KPC was localized in 3 of 9 cases and in the medullary type 3 of 7 cases. If KPC was regarded as the marker of the basal cell as shown in BPH, it would be speculated that the absence of KPC occurred in some type of prostatic cancer showed the disappearance of basal cell. That is, KPC could not be detected in large acinar, small acinar and column and cord type, while KPC remained completely or partially in the cribriform, fused gland and medullary type. These histochemical alteration would suggest the different degree of malignancy in the various histological type of prostatic cancer.

Adenocarcinoma↗

[Pathomorphological study of local extension and progression of prostate cancer].

The interrelationship among localization of tumor, local extension, lymph node metastasis and various histological grades was investigated in 31 consecutive series of prostate cancer treated by radical prostatectomy. Surgical specimens were examined by step sections cut perpendicular to the urethra. Each tumor was graded histologically in accordance with WHO-Mostofi grading (evaluated by nuclear anaplasia and structural differentiation), Gleason's and M.D. Anderson's grading systems. The areas of the prostate was divided into 4 quadrants delimited vertically along the urethral axis and transversely at the level of utricle, i.e. anterior/superior, anterior/inferior, posterior/superior and posterior/inferior quadrants. Topographical localization and extension of each tumor was examined in accordance with the above area subdivision. Every tumor was growing at least in the posterior/inferior area. All cases with tumor progression to the anterior/superior area also revealed extensive tumor growth in the other two or three quadrants. Therefore, prostate cancer appears to be originated from the posterior/inferior area of the prostate and terminated in the anterior/superior area as local extension. In 31 cases examined, capsular invasion was noted in 22, seminal vesicle invasion in 16, and lymph node metastasis in 12 cases. All cases with seminal vesicle invasion also showed capsular invasion. None of the cases without capsular and/or seminal vesicle invasion had lymph node metastasis. Thus, it is inferred that prostate cancer is initially growing locally, extending to the capsule and seminal vesicle and then metastasizes to the pelvic lymph nodes. As for the histological grading, higher grade tumors tended to show higher incidence of capsular and seminal vesicle invasion and lymph node metastasis.(ABSTRACT TRUNCATED AT 250 WORDS)

Humans↗

[Stereo architecture of the connective tissue papillae of lips and gingiva in newborn dogs].

The surface structure of the connective tissue papillae of lips and gingiva of newborn dogs 1 and 4 weeks after birth were observed by scanning electron microscopy. 1. Long term HCl treatment successfully removed the epithelial cell layer from the connective tissue over a large area of fixed material. 2. Connective tissue papillae of labial skin, labial mucosa and alveolar and gingival mucosa were exposed and it became clear that connective tissue papillae were highly developed at the labial margin and just beneath the gingival margin. 3. In the hair growing area of the labial skin, connective tissue papillae became smaller, and some ridge-like structures were found running vertically. 4. On the lining mucosa such as the labial and alveolar mucosa, the surface of the connective tissue papillae showed only ridge-like structures running vertically. 5. From the results of both light and electron microscopy, we concluded that there was a tendency for the area to have a thick epithelial cell layer which contained highly developed connective tissue papillae. This suggested that the blood vessels in the connective tissue papillae can carry nutrients closer to more epithelial cells penetrating deeply into the epithelium thickness.

Animals↗

[Three-dimensional structure of the connective tissue core of the lingual papillae in the crab-eating macaque (Macaca fascicularis)].

The three-dimensional structure of the connective tissue core (CTC) of the four types of lingual papillae of the crab-eating macaque (Macaca fascicularis) was studied by scanning electron microscopy after removal of the epithelial cell layer by long-term treatment with hydrochloric acid at room temperature and compared with the results obtained from light microscopy. 1) Filiform papillae are densely distributed on the dorsal surface of the anterior two thirds of the tongue. Fungiform papillae are scattered among these filiform papillae, and are numerous at the anterior margin of the tongue. The connective tissue core of each filiform papilla looked like a lifting human hand with its palm towards the tongue tip. By using light microscopy, AF-positive elastic fibers were accumurated very densely just beneath the basal region of the anterior column epithelium of each filiform papilla. 2) CTC of fungiform papilla showed coralliform structure whose branches were ramified a few times. On the top of each branch there was a small depression where a taste bud was situated. 3) After removal of the epithelial cell layer of the foliate papilla, longitudinal grooves coinciding with the epithelial slits were observed. Some glandular ducts were seen protruding towards the exfoliated epithelium. 4) After removal of the covering epithelium of the vallate papilla, numerous small rod-shaped secondary CT cores appeared on the large primary CT core.

Animals↗

[Treatment of chronic myelogenous leukemia (CML)--VP(M) regimen starting during its chronic phase, and the second nation-wide survey on the long-term survivors of CML in Japan].

Eighty-three patients in the chronic phase of Ph1-positive chronic myelogenous leukemia (CML) have been treated with busulfan or other alkylating agents in a conventional way hitherto acknowledged. During its chronic phase, 31 cases of these 83 had received an additional intermittent therapy every 4 to 6 months, consisting of vincristine 2 mg or vindesine 3 mg per week, prednisolone 20 to 30 mg per day, and partly 6-mercaptopurine 50 to 100 mg, combined with allopurinol 200 to 300 mg per day for 2 to 3 weeks. The 50% survival of these patients using the Kaplan-Meier's method was 73, 7 months and 5-year survival was 70.2%, while those of the remaining patients were 41.2 months and 13.4%, respectively. The second nation-wide survey of long-term survivors of CML in Japan was attempted. CML totalling 195 surviving over 7 years from the initial diagnosis and 113 of CML surviving over one year from the blastic crisis had been collected by the end of March 1988. The longest survivors of the former group was for 21.3 years, while the latter 4.6 years. In addition, recent increase of the annual incidence of the above both groups was clarified. These results strongly support the progress of chemotherapy of CML in recent years.

Adolescent↗

[Chemotherapy of chronic myelogenous leukemia--VP(M) regimen initiated during its chronic phase, and evaluation of MCNU in the phase of blastic crisis].

Seventy-four patients in the chronic phase of Ph1-positive chronic myelogenous leukemia (CML) have been treated with busulfan or other alkylating agents in a conventional way. During its chronic phase, 24 of these 74 cases had received additional intermittent therapy every 4 to 6 months, consisting of vincristine 2 mg or vindesine 3 mg per week, prednisolone 20-30 mg per day and partly 6 mercaptopurine 50 to 100 mg, combined with allopurinol 200 to 300 mg per day for 2 to 3 weeks. The 50% survival of these patients using the Kaplan-Meier's method was 73.7 months and 5-year survival was 69.6%, against 40.5 months and 14.4%, respectively, in the remaining patients. Nine patients in the blastic or accelerated phase of Ph1-positive CML have been treated with new regimens including MCNU. All cases had been refractory for usual types of induction chemotherapy. The new regimen consisted of MCNU 50-100 mg, combined with vindesine or 6-MP plus allopurinol or prednisolone. Five out of 9 cases attained complete remission and 1 partial remission. The major adverse effect of this regimen was slight liver damage. MCNU could be regarded as an useful agent in the blastic phase as well as in the chronic phase of CML.

Adolescent↗

Use of a bacteriophage-derived endo-N-acetylneuraminidase and an equine antipolysialyl antibody to characterize the polysialyl residues in salmonid fish egg polysialoglycoproteins. Substrate and immunospecificity studies.

Polysialoglycoproteins (PSGP), a class of glycoproteins containing oligo(poly)sialylglycan chains, are the major glycoprotein components in cortical alveoli of a number of Salmonidae fish eggs. Lake trout, Salvelinus namaycush, egg PSGP (PSGP(Sn)) differs from rainbow trout, Salmo gairdneri, egg PSGP (PSGP(Sg)) in its sialic acid composition; the former contains both N-acetyl- and N-glycolyl-D-neuraminic acid residues, designated Neu5Ac and Neu5Gc, while the latter contains only Neu5Gc residues. Fragmentation analysis of oligo(poly)sialyl chains in lake trout PSGP(Sn) has established that there are two distinct types of oligo(poly)sialyl structures in this PSGP molecule, namely alpha-2,8-linked oligo/poly(Neu5Ac) and alpha-2,8-linked oligo/poly(Neu5Gc). No hybrid structure having both Neu5Ac and Neu5Gc residues in the fragment oligosialic acids was detected. These two distinct PSGP preparations from eggs of lake trout and rainbow trout have been used to compare their immunoreactivity with anti-polysialyl antibodies (H.46) and sensitivity to a bacteriophage-derived (Escherichia coli K1F) endo-N-acetylneuraminidase (Endo-N). H.46 was found to cross-react only with lake trout PSGP(Sn) in immunodiffusion assays but not with rainbow trout PSGP(Sg), indicating that H.46 is a specific probe for alpha-2,8-linked poly(Neu5Ac) but not for poly(Neu5Gc). In contrast, Endo-N was found to catalyze the hydrolysis of both alpha-2,8-linked poly (Neu5Ac) and poly(Neu5Gc), so that this enzyme can be used as a diagnostic reagent for detecting both types of polysialic acids. H.46 was used in indirect immunofluorescence experiments to localize PSGP(Sn) in cortical alveoli isolated from lake trout eggs.

Animals↗

Molecular cloning and characterization of cDNAs coding for apo-polysialoglycoprotein of rainbow trout eggs. Multiple mRNA species transcribed from multiple genes contain diverged numbers of exact 39-base (13-amino acid) repeats.

Polysialoglycoprotein (PSGP) of unfertilized eggs of rainbow trout (Salmo gairdneri) consists of tandem repeats (about 25) of a glycotridecapeptide, Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Gly (* denotes the attachment site of a polysialoglycan chain) (Kitajima, K., Inoue, Y., and Inoue, S. (1986) J. Biol. Chem. 261, 5262-5269). By using oligodeoxynucleotide probes based on the above sequence, we isolated a genomic clone for apoPSGP which contains 39-base pair repeats (5'-GACGACGCCACCTCTGAAGCT-GCGACCGGCCCGTCTGGC-3') encoding the tridecapeptide. Using a fragment of this genomic DNA as a probe, we next screened a cDNA library constructed with mRNA from immature ovaries of rainbow trout. Nucleotide sequencing analyses of cDNA clones thus obtained revealed that apoPSGP is encoded by multiple mRNA species consisting of diverged numbers (6-32) of the 39-base repeat encoding the tridecapeptide unit and homologous 5'- and 3'-bordering regions. The encoded protein consists of three distinct regions: the N-region consisting of a putative signal peptide and a pro-peptide, the R-region containing diverged numbers of the tandem repeat of 13-amino acid residues, and the C-region with six amino acid residues. Southern blot analysis showed that multiple mRNAs are transcribed from multiple genes for apoPSGP containing diverged numbers of the 39-base pair repeat. Thus, the genes for apoPSGP constitute a multigene family. Expression of the mRNAs is stage and organ specific, i.e. they are expressed only in immature ovaries and not in mature ovaries or in any other organ.

Amino Acid Sequence↗

Comparative structures of the apopolysialoglycoproteins from unfertilized and fertilized eggs of salmonid fishes.

The complete amino acid sequence of the major polysialoglycoproteins (PSGPs) from two genera of salmonid fish eggs, Salvelinus and Oncorhynchus, has been determined. The occurrence of tandem repeats of a genus-specific dodeca- and tridecapeptide was found for the apoPSGP of Salvelinus leucomaenis pluvius (Slp) and Oncorhynchus masou ishikawai (Omi), respectively, their amino acid sequences being highly homologous with that of rainbow trout [Salmo gairdneri (Sg)] apoPSGP (*denotes the glycosylation site; mean value of N = approximately 25): H-PSGP(Slp): (Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-)N H-PSGP(Omi): (Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Ser-)N H-PSGP(Sg): (Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Gly-)N Within 5-7 min following fertilization H-PSGP is converted to the low-molecular-mass PSGP (L-PSGP) by a specific protease (PSGPase). We have purified L-PSGP from the fertilized eggs of S. leucomaenis pluvius and Oncorhynchus keta (chum salmon) and compared it with rainbow trout egg L-PSGP(Sg) by analysis of their amino acid sequence: L-PSGP(Slp): Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Asp L-PSGP(Ok): Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Ser L-PSGP(Sg): Asp-Asp-Ala-Thr*-Ser*-Glu-Ala-Ala-Thr*-Gly-Pro-Ser-Gly The data support the conclusion that H-PSGP is degraded in vivo 5-7 min after fertilization to L-PSGP by proteolytic cleavage at the position two residues C-terminally to the Pro residue, i.e., -Pro-Ser-Xaa-Asp-(Xaa = either Gly, Ser, or Asp) by the action of PSGPase.

Amino Acid Sequence↗

KDN-glycoprotein: a novel deaminated neuraminic acid-rich glycoprotein isolated from vitelline envelope of rainbow trout eggs.

A new acidic glycoprotein containing deaminated neuraminic acid (KDN = 3-deoxy-D-glycero-D-galacto-nonulosonic acid; greater than 50%, w/w) was isolated from vitelline envelope of the unfertilized eggs of rainbow trout (Salmo gairdneri). This glycoprotein is designated as "KDN-glycoprotein" because it contains only KDN but no sialic acid as the acidic carbohydrate moieties. Other major carbohydrate components of KDN-glycoprotein were Gal and GalNAc. Thr and Ala accounted for 71% (mol/mol) of amino acid composition. A possible occurrence of KDN-KDN linkages, i.e. oligoKDN groups has been suggested in the carbohydrate chains presumably linked O-glycosidically to the core protein.

Amino Acids↗

Exclusion chromatography with controlled-pore glass beads to isolate Chlorella chromatin and its applications.

A simple and rapid method was developed to isolate chromatin from the unicellular alga, Chlorella, by exclusion chromatography utilizing controlled-pore glass beads. This method takes advantage of the giant size of the chromatin supramolecules and does not require the preliminary isolation of cell nuclei. In order to raise the histone yield, commercially available materials were silanized with dimethyldichlorosilane. The isolated algal chromatin had properties similar to those of other organisms, and the histones contained all five components found in calf thymus. A hierarchy of the higher order structures was also observed in the algal chromatin. This method can be used for the study of chromatin in various cell types, especially in microbial cells, from the viewpoints of not only mere preparation but also cell dynamics and fractionation in relation to the specific components or activities. Some application examples are presented.

Cell Cycle↗

A proteinase associated with cortices of rainbow trout eggs and involved in fertilization-induced depolymerization of polysialoglycoproteins.

A novel proteinase that acts on polysialoglycoprotein (PSGP) was found in the cortex fraction of the unfertilized eggs of rainbow trout. This enzyme (designated PSGPase) is responsible for specific depolymerization of cortical vesicular 200- to 9-kDa PSGP in vivo upon fertilization. We have succeeded in measuring the enzyme activity in an in vitro system by using 3H-labeled PSGP as the substrate. In the in vitro system PSGPase is active only at concentrations of NaCl below 40 mM and at low temperature (optimum temperature, about 16 degrees C), which are the conditions most suitable for egg activation.

Animals↗

A B-cell line having chromosome 14 aberration at break band q11 derived from an adult T-cell leukemia patient.

A B-cell line having translocations of chromosome 14 at break band q11 (the assigned locus of the alpha-chain gene of the T-cell antigen receptor) and chromosome 3 at break band p25 (the assigned locus of the c-raf-1 oncogene) was established from peripheral blood leukocytes of an adult T-cell leukemia (ATL) patient. The same chromosome 14 aberration at break band q11 and chromosome 3 aberration at break band p25 were also found in fresh T-cell leukemia cells. The B-cell line is surface immunoglobulin (sIg)+, immunoglobulin gene rearrangement+, ATL-specific antigen (ATLA)+, HTLV-1 proviral genome+, Epstein-Barr virus (EBV)-associated nuclear antigen (EBNA)+ and the EBV DNA genome+. The fresh T-leukemic cells were T-cell receptor gene rearrangement+, the HTLV-1 proviral genome+ and EBV DNA genome.

B-Lymphocytes↗