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Y Tajima

Publications and source records attributed to Y Tajima.

At least 109 records · Page 6Linked to original sources
PubMed1996

In vivo modulation of proliferating cell nuclear antigen in growth plate chondrocytes from normal, hypophysectomized, growth hormone-treated hypophysectomized rats: a comparative immunohistochemical study with image analysis.

Growth hormone (GH) regulates the proliferation and maturation of chondrocytes in the epiphyseal growth plate, in which a temporal dimension is superimposed on the septal organization of the tissue. In this study we investigated the in vivo effects of hypophysectomy (Hypox) and injection of GH into Hypox animals (Hypox + GH) on the proliferative activity of the growth plate chondrocytes. We assessed the immunohistochemical expression of proliferating cell nuclear antigen (PCNA) in paraffin-embedded tissues, using monoclonal antibody PC 10 against PCNA combined with immunogold-silver staining. We subjected the immunostained sections to computer-based image analysis by ACAS 570 interactive laser cytometry employing a conventional microscopic light source. Hypox was carried out on 20 rats at 8 weeks of age, half of which received a hypodermic injection of human GH at a dose of 1 IU/kg twice a day for 1 week after the operation. Another group of five rats of the same age were used as normal controls. In normal rats, a distinct PCNA immunoreaction was observed in the proliferative zone, whereas a remarkable diminution of the number of immunoreactive cells in this zone was apparent in Hypox animals. On the other hand, marked hyperplasia of PCNA-positive cells was seen in the proliferative zone of the Hypox + GH rat growth plate. The immunoreactive cells of this zone in Hypox + GH animals exhibited increased nuclear size and staining intensity of PCNA compared with those in normal and Hypox rats. These findings were further confirmed by computer-based image analysis of the specimens in terms of cell integrated value, area, perimeter, and shape factor. These different patterns of PCNA expression may imply that GH specifically promotes the proliferation phase of the chondrocytes in the proliferative zone. The data also suggest that GH influences not only cell replication activity but also cell kinetics of chondrocytes in the growth plate during their lifespan.

Animals↗
PubMed1996

Synergistic effect of polyoxotungstates in combination with beta-lactam antibiotics on antibacterial activity against methicillin-resistant Staphylococcus aureus.

The in vitro antibacterial effect of the combination of various polyoxometalates with beta-lactam antibiotics on methicillin-resistant Staphylococcus aureus (MRSA) strains is investigated by the use of both the National Committee for Clinical Laboratory Standards (NCCLS) disk method and the agar dilution method. Keggin-structural polyoxotungstates such as K7[PTi2W10O40].6H2O (5) and K7[BVW11O40].7H2O (8) and their lacunary species formulated by [XW11O39]n- and[XW9O34]n- potentiated the antibacterial activity of beta-lactam antibiotics such as oxacillin, piperacillin and cefazolin on MRSA with high selectivity. The depression of bacterial growth with the coexistence of polyoxotungstates and oxacillin was confirmed by the measurement of the bacterial turbidity at 660nm. Polyoxomolybdates and polyoxovanadates, on the other hand, exhibited hardly any synergistic effect in combination with oxacillin. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) of the membrane proteins separated from MRSA revealed that polyoxotungstates depressed the formation of penicillin-binding protein 2'(PBP2'), an enzyme which is essential for cell wall construction in the MRSA growth. It is concluded that polyoxotungstates make the MRSA strains susceptible to beta-lactam antibiotics.

Anti-Bacterial Agents↗
PubMed1996

[Mini review: a factor enhanced the antibacterial effect of beta-lactams on methicillin-resistant Staphylococcus aureus].

We found a factor (Factor T) in aged mixtures of tungstate and phosphate which greatly enhances the antibacterial effects of beta-lactams on methicillin-resistant Staphylococcus aureus (MRSA), while Factor T alone did not strongly inhibit bacterial growth. The effect on methicillin-susceptible S.aureus was weak. There was no synergism of Factor T with other classes of antibiotics, nor with other groups of bacteria. Factor T is probably a complex of phosphate and tungstate, and reduced the expression of penicillin-binding protein-2', thus sensitizing the MRSA strains to beta-lactams.

Drug Synergism↗
PubMed1995

Successful surgical treatment of secondary Kwashiorkor after total gastrectomy: report of a case.

We report herein the case of a 56-year-old woman who developed secondary Kwashiorkor 9 years after undergoing a total gastrectomy for early gastric cancer. Until she began developing the symptoms of Kwashiorkor, including general fatigue, edema of the face and extremities, anemia, alopecia, and weight loss, she had been leading a normal life post-gastrectomy. Her symptoms were alleviated by total parenteral nutrition (TPN) therapy, but reappeared soon after TPN therapy was discontinued. Therefore, she required several subsequent courses of TPN. In an attempt to permanently resolve the ongoing Kwashiorkor symptoms, reconstructive surgery involving transposition of the jejunum from the previous Graham method to the interposition method was performed 10 years after the initial gastrectomy. After the second operation, her malnutrition was completely alleviated, and she has been in good health for the 8 years since. To our knowledge, there has been no other report of the symptoms of secondary Kwashiorkor after total gastrectomy being alleviated by altering the procedure of reconstruction of the intestinal tract. Thus, we recommend surgical treatment to alter the digestive continuity to a more physiological pathway for selected patients with secondary Kwashiorkor syndrome.

Anastomosis, Surgical↗
PubMed1995

Insulin-like growth factor-I and transforming growth factor-alpha stimulate differentiation of type A spermatogonia in organ culture of adult mouse cryptorchid testes.

This study assessed the effect of growth factors on testicular germ cell differentiation in vitro. Testicular fragments of experimentally prepared cryptorchid testes of adult mice were cultured for 9 days in serum-free media containing various concentrations of IGF-I, TGF-alpha, FGF, and PDGF. Their histology was then examined under a light microscope. Each type of germ cell and mitotic cell in the seminiferous tubules was counted per 1000 Sertoli cells. IGF-I at a concentration of 10 ng/ml induced maximal differentiation of type A spermatogonia. TGF-alpha at concentrations ranging from 1 to 10 ng/ml also stimulated differentiation, whereas FGF and PDGF did not show any stimulation of spermatogonial differentiation in this experimental system.

Animals↗
PubMed1995

[Clinical bacteriological analysis of Vibrio vulnificus infection--a report of five case].

Clinical features in Vibrio infection are generally represented by gastrointestinal involvements such as food poisoning, and its prognosis is usually good. However, Vibrio vulnificus infection not uncommonly causes serious problems including sepsis, necrotizing fasciitis of the extremities, and other conditions, sometimes resulting in fatal outcome. In the present study, we analyzed clinical microbiological aspects of five cases with V. vulnificus infection. All the strains of V. vulnificus isolated in five patients are oxidase-positive Gram negative rods presenting comma-like configuration, which were yielded on TCBS agar forming green colonies; they were grayish-white in color and viscous in texture on 5% sheep blood agar, identification of bacteria were done using VITEK AMS (BioMérieux). Piperacillin and third-generation cephalosporins were found to have bactericidal activities against these strains. All five cases we experienced have primary ailments, and three cases out of the five had taken perishable sea-food before showing disease symptoms. V. vulnificus has two infection channels; one is external wound and the other is oral intake. The latter is said that it may become serious. This has a rather short period from the starting the symptoms to death, and there is high death rate. For life-saving, it is inevitably necessary to dose an effective antibacterial medicine in the early stage. If we suspect this bacteria in the test laboratory, it is important to report this to the clinical doctor. In other words, this is one of the bacteria that needs prompt treatment and further microbiology testing.

Adult↗
PubMed1995

[Peripheral T-cell lymphoma with abundant ATL-like cells in the blood].

A 69-year-old woman was admitted to our hospital because of leucocytosis and systemic lymphadenopathy. On admission, white blood cell count was 163,000/microliters, most of which consisted of flower-like cells with convoluted nuclei in the peripheral blood. In the abnormal lymphocyte cells surface-marker test by flow cytometry showed that they expressed CD2, CD3, CD4, CD29, CD45RA, and CD38, but not CD8, CD16, and CD25. Serum anti-Human T-lymphotropic virus type-I (HTLV-I) antibody was negative in particle agglutination, enzyme-linked immunosorbent assay (ELISA) and western-blotting assay. HTLV-I proviral DNA in the abnormal lymphocyte cells was not detected by southern blotting hybridization technique. Moreover, HTLV-I provirus was not detected using a polymerase-chain-reaction (PCR). A monoclonal rearrangement of the TCR-beta chain gene was evident by using DNA probe in southern blot hybridization. Because of the rapid progress of the disease, chemotherapy was started immediately after admission. Though, this patient became refractory, and she died about 1 year after admission.

Aged↗
PubMed1995

[Arylsulfatase].

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Arylsulfatases↗
PubMed1994

Molecular cloning of a novel Ca(2+)-binding protein (calmegin) specifically expressed during male meiotic germ cell development.

During mammalian spermatogenesis, many specific molecules are expressed. We have recently identified a 93-kDa male meiotic germ cell-specific antigen (Meg 1) exclusively expressed in germ cells from the pachytene spermatocyte to the spermatid stage using the monoclonal antibody TRA 369 (Watanabe, D., Sawada, K., Koshimizu, U., Kagawa, T., and Nishimune, Y. (1992) Mol. Reprod. Dev. 33, 307-312). In this study, we cloned a cDNA representing this antigen from a mouse testis cDNA expression library, using the monoclonal antibody TRA 369. Northern blotting showed that this transcript was 2.3 kilobases in length and was expressed only in the testis and not in other somatic tissues or in the ovary. The expression of the mRNA was first detected at the pachytene spermatocyte stage of male germ cell development, and this expression was correlated with the expression of the protein. Sequence analysis of the cDNA revealed that the predicted protein consists of 611 amino acids, including a hydrophobic NH2 terminus characteristic of a signal peptide, two sets of internal repetitive sequences (four repeats of IPDPSAVKPEDWDD and GEWXPPMIPNPXYQ), and a hydrophilic COOH terminus. The deduced amino acid sequence has 58% homology with dog calnexin (the ER membrane phosphoprotein of pancreatic cells) and significant partial homology with calreticulin (high affinity Ca(2+)-binding protein of the ER membrane) at the repetitive sequence. Furthermore, we demonstrated the 45Ca2+ binding ability of this antigen by a 45Ca2+ overlay assay, and the name calmegin is proposed for this antigen. Calmegin is a novel Ca(2+)-binding protein that is specifically expressed in spermatogenesis. The highly regulated, specific, and abundant expression of calmegin suggests that it has important roles in spermatogenesis.

Amino Acid Sequence↗
PubMed1994

Characterization of an established transplantable adenocarcinoma of the gallbladder in Syrian golden hamster.

A carcinoma of the gallbladder was transplantable in Syrian golden hamsters. The tumor was induced by subcutaneous injection of N-nitrosobis (2-oxopropyl) amine (BOP) following dissection of the common duct and preparation of a cholecysto-duodenostomy. The histology revealed a poorly differentiated adenocarcinoma. The tumor was inoculated into the cavity of the gallbladder and subcutaneous tissue of the hamster and was transplantable (uptake rate was 100%). This tumor expressed blood group-related antigens, including A, H, and P-glycoproteins. To our knowledge, this is the first report of carcinoma of the gallbladder transplantable in a laboratory animal.

Adenocarcinoma↗
PubMed1994

X-ray evidence for the elongation of thin and thick filaments during isometric contraction of a molluscan smooth muscle.

The elongation of thin and thick filaments during isometric contraction of a molluscan smooth muscle was studied by measuring spacing changes of meridional reflections in the medium-angle X-ray diffraction pattern. X-ray patterns from the anterior byssus retractor muscle of Mytilus edulis in the resting, active, and catch states were taken from the same part of a muscle bundle at a fixed specimen-to-detector distance, using imaging plates and 10 s exposure to synchrotron radiation. The third-order reflection (9.2 A) of the axial period of actin, and the fourteenth-order reflection (10.4 A) of the axial subunit-repeat of the thick filament are increased in spacing in the active and catch states. From accurately measured changes in the axial distance of the 9.2 A layer line from the origin, thin filament elongations in the active and catch states are estimated to be 0.48 and 0.32%, respectively, in a muscle that maintains a tension of 12.2 kg cm-2 in the active state and 9.8 kg cm-2 in the catch state. Thick filament elongations in the active and catch states are similarly estimated to be 0.33, and 0.28%, respectively, based on the axial shift of the 10.4 A reflection. The 0.48% elongation of the thin filament in the active state agrees with an elongation that is presumed by White and Thorson (1973) to estimate the lower limit of the thin-filament stiffness. It seems that in the catch state the activated and resting thin filament structures are intermixed. The activated parts of the thin filament are probably more elongated than the apparent value, 0.32%.

Actin Cytoskeleton↗
PubMed1994

Computer-aided image analysis applied to immunogold-silver staining: evaluation of proliferating cell nuclear antigen (PCNA)-reactive sites in paraffin sections.

Feasibility of the combination of the immunogold-silver staining method (IGSS) and computer-aided image analysis was assessed for the detection of antigen in an immunostained, paraffin-embedded section. Using low-temperature IGSS, we stained a specimen of human oral squamous cell carcinoma with a monoclonal antibody, PC 10, against a proliferating cell nuclear antigen (PCNA/cyclin), and the section was analyzed by ACAS 570 interactive laser cytometry. The PCNA-positive cells, exhibiting a heteromorphic texture, were contrasted by the dark staining of their nuclei, but showed heterogeneity in staining intensity from cell to cell. Using a conventional microscope light source rather than a laser, and by employing the COMPLEMENT DATA program (which permits inversion of the data values) installed in the ACAS 570 software system, we were able to obtain a 'complemental image' which replicated the real immunohisto-morphology. Approximately 30-35 cells from three different areas in the same section were selected by DEFINE CELL and MARK AREA programs, and quantitative image analysis was performed in terms of cell integrated value, area, perimeter, and shape factor indicated in histogram form. The combined utilization of IGSS with computer-aided image analysis was demonstrated to offer a crucial advantage for the quantitative assessment of immunostained sections.

Humans↗
PubMed1994

Immunohistochemical analysis of EGF in epiphyseal growth plate from normal, hypophysectomized, and growth hormone-treated hypophysectomized rats.

Epiphyseal growth plate cartilages from the proximal tibia of normal, hypophysectomized, and growth hormone (GH)-treated hypophysectomized rats were subjected to immunohistochemistry for detection of epidermal growth factor (EGF). In the normal growth plate, EGF was distributed mainly in the proliferative zone. Hypophysectomy resulted in considerable atrophy of the chondrocytes and the cartilage matrix (a decreased number of mature-type chondrocytes and a decreased ratio of proliferating to hypertrophic chondrocytes) and a significant diminution of EGF immunoreactivity. Treatment with GH reversed these effects of hypophysectomy, causing an increased thickness of the growth plate and EGF-reactive sites in all chondrocyte layers. The most intense immunostaining for EGF, however, was frequently seen in the nuclei of chondrocytes with flattened appearance. It appears that EGF could be incorporated or synthesized in chondrocytes having marked mitogenic activity. The present results, taken with previous data on EGF involvement in growth of cartilaginous tissue in vivo and in vitro, strongly suggest that EGF-immunoreactive chondrocytes are involved in cartilage proliferation and growth under the specific influence of GH.

Animals↗
PubMed1994

Malignant melanoma within an intradermal nevus.

We describe a case of malignant "dermal" melanoma that arose within a preexisting intradermal nevus. Clinically, the lesion had recently enlarged. Histologically, two patterns were noted. One was an intradermal nevus in the upper portion of the dermis; the other was a deeper nodule composed of malignant neoplastic cells that extended into the reticular dermis. No melanocytic epidermal junctional activity was noted. Despite careful clinical investigation, no alternative primary source was found. Neoplastic transformation of the intradermal nevus without junctional activity is our proposed interpretation of the lesion's histology. Immunohistochemical stains demonstrated that the deeper dermal neoplastic cells were positive for both HMB-45 and PCNA, whereas the superficial nevoid-appearing cells were negative; these findings support our postulate that this melanoma arose within an intradermal nevus. It is important to distinguish this neoplasm from other diagnostic possibilities, including a metastatic lesion originating from another site.

Aged↗
PubMed1994

Possible mechanism of action of beta-lactam-enhancing factor on methicillin-resistant Staphylococcus aureus.

We have recently found a factor (Factor T) in aged mixtures of tungstate and phosphate which greatly enhances the antibacterial effects of beta-lactams on methicillin-resistant strains of staphylococcal species such as methicillin-resistant Staphylococcus aureus (MRSA), but shows only weak effects on methicillin-susceptible S. aureus and bacterial strains other than staphylococci. Factor T alone did not strongly inhibit cell metabolism and bacterial growth unless an excess amount was added. When Factor T was added to the culture medium beforehand, the growth of MRSA cells was rapidly suppressed just after addition of oxacillin (MPIPC). However, the growth of the cells was inhibited gradually when these two reagents were added in reverse order. For full expression of the enhancing effect, it seemed necessary for cells of MRSA strains to be incubated with Factor T for at least 2-3 hr. When the cells were washed after being sensitized by incubating them for 5 hr with Factor T, it took approximately 1 hr for the cells to recover their resistance to MPIPC. Factor T reduced the amount of penicillin-binding protein-2' (PBP 2'), and thus sensitized the MRSA strains to beta-lactams.

Anti-Bacterial Agents↗