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J Akiba

Publications and source records attributed to J Akiba.

At least 19 recordsLinked to original sources
PubMed2001

Expression of angiogenic factors, basic fibroblast growth factor and vascular endothelial growth factor, in human biliary tract carcinoma cell lines.

In order to clarify angiogenic mechanism in biliary tract carcinoma, expressions and functions of basic fibroblast growth factor (bFGF) and its receptors (FGFR-1-4), and vascular endothelial growth factor (VEGF) and its receptors were investigated by using human biliary tract carcinoma cell lines (KMC-1, KMC-2, KMBC and KMG-C). Expression of bFGF was confirmed in KMC-1 and KMC-2, and that of FGFR-1-4 in all the cell lines except no FGFR-2 in KMC-2. Expression of VEGF was detected in all the cell lines, whereas the cell lines did not express VEGF receptors. Addition of anti-bFGF neutralizing antibody to the medium did not suppress cell proliferation, whereas exogenous bFGF with or without heparin accelerated cell proliferation in all cell lines. Addition of anti-bFGF neutralizing antibody or anti-VEGF neutralizing antibody to the co-culture of human umbilical vascular endothelial cells (HUVEC) and KMC-2 suppressed the proliferation of HUVEC. Surgically obtained cholangiocarcinoma tissues (n=7) were immunohistochemically negative to bFGF, while six of the seven were positive to VEGF. These findings suggested that human biliary tract carcinoma cells express both bFGF and VEGF not as autocrine growth factors but as angiogenic factors. On the other hand, expression of VEGF was found at a higher frequency than bFGF both in the cell lines and tissues.

Journal Article↗
PubMed2001

Retinal thickness measurements with optical coherence tomography and the scanning retinal thickness analyzer.

PURPOSE: To assess the reproducibility of retinal thickness measurements in normal subjects and to compare foveal thickness using optical coherence tomography (OCT) and the scanning retinal thickness analyzer (RTA). METHODS: Two examiners performed foveal thickness measurements in 24 eyes of 12 healthy subjects using both OCT and the scanning RTA. Intraclass correlation coefficients (ICC) (intra-examiner and inter-examiner) were calculated for the paired foveal thickness measurements obtained with each instrument. RESULTS: The average foveal thicknesses measured with OCT and the scanning RTA were 155.1 +/- 14.9 microm and 107.8 +/- 18.6 microm, respectively. The intra-examiner ICCs from the two sessions using the OCT and the scanning RTA were 0.99 and 0.78 and 0.89 and 0.99, respectively. The inter-examiner ICCs of the OCT and the scanning RTA were 0.99 and 0.99, respectively. There was a significant correlation between the foveal thickness measurements with these two instruments (R2 = 0.629, P < 0.0001). CONCLUSION: The foveal thicknesses measured using OCT and the scanning RTA in healthy subjects agreed with the previously reported data on foveal thickness. Both instruments can reproducibly quantitate foveal thickness.

Adult↗
PubMed2001

Variations of Weiss's ring.

BACKGROUND: Weiss's ring is an important index for diagnosing a posterior vitreous detachment (PVD). The authors studied the configurations of Weiss's ring because the ring has several variations. METHODS: Weiss's ring was examined biomicroscopically in 223 eyes with PVD and documented videographically using a scanning laser ophthalmoscope. The configurations of Weiss's ring were classified into four groups: a complete ring, a partial ring, a ball-like opacity, and a hole without a ring. RESULTS: In the 223 eyes with PVD, Weiss's ring was categorized as a complete ring in 63 eyes (28.3%), a partial ring in 128 eyes (57.4%), a ball-like opacity in 17 eyes (7.6%), and a hole without a ring in 15 eyes (6.7%). A complete ring was observed in 8 (57.1%) of 14 eyes with hyperopia (+3 diopters or more), in 25 (28.7%) of 87 eyes with emmetropia (between -1 and +1 diopter), and in 10 (16.1%) of 62 eyes with myopia (-3 diopters or more). Six months after the initial examinations, the contour of Weiss's ring remained unchanged in 86 (96.6%) of 89 eyes with fresh PVD. CONCLUSIONS: Scanning laser ophthalmoscope is a useful tool for observing Weiss's ring. A "classic" annular opacity around a hole in the prepapillary posterior vitreous cortex represents less than one third of the configurations of Weiss's ring, indicating that the term "ring" is erroneous.

Aged↗
PubMed2001

Expression and function of interleukin-8 in human hepatocellular carcinoma.

Expression and functions of interleukin (IL)-8, a pro-inflammatory cytokine with angiogenesis action, was examined in 23 surgically resected hepatocellular carcinoma (HCC) specimens and 7 HCC cell lines. In all HCC tissues, IL-8 expression was confirmed with reverse-transcription polymerase chain reaction method and enzyme-linked immunosorbent assay, and immunohistochemistry showed HCC cells were the major producer of IL-8 in the tissues. Microvessel density was measured by the double immunohistochemical staining of muscular vessels in HCC tissues, but the density was not related to the level of IL-8 in the HCC tissues. On the other hand, in the co-culture of human umbilical vein endothelial cells (HUVEC) and a HCC cell line (KIM-1), IL-8 produced by KIM-1 significantly accelerated the proliferation of HUVEC. In addition, cases with a high IL-8 level in cancerous tissue had a significantly higher frequency of portal vein invasion, venous invasion and bile duct invasion (p<0.05). In the cultures of 7 HCC cell lines IL-8 secretion into culture medium increased with the treatment of IL-1beta or tumor necrosis factor-alpha. This showed IL-8 expression is regulated by inflammatory cytokines. IL-8 produced by HCC is an angiogenesis factor of HCC, but it could have a much more important role in the invasion and metastasis of HCC.

Aged↗
PubMed2000

Scanning laser ophthalmoscope correlations with biomicroscopic findings and foveal function after macular hole closure.

OBJECTIVE: To investigate the relation between foveal findings and visual function in eyes with a resolved idiopathic macular hole after vitreous surgery. METHODS: We divided 28 eyes with postoperative idiopathic macular hole resolution into 3 groups based on postoperative biomicroscopic foveal findings of complete closure, partial closure, or atrophic closure. To evaluate foveal retinal function, scanning laser ophthalmoscope (SLO) microperimetry was performed preoperatively and 6 months postoperatively. RESULTS: Postoperatively in 18 eyes (64%), the foveal images became normal or almost normal and were classified as having complete closure, 6 eyes (21%) were classified as having partial closure, and 4 eyes (14%) as having atrophic closure. The corresponding visual acuity levels 6 months postoperatively were, respectively, 0.10, 0.35, and 0.64 (P<.01) based on LogMAR analysis. Preoperative SLO microperimetry detected an absolute scotoma at the bottom of all macular holes; postoperatively, the absolute scotoma disappeared in the 18 eyes with complete hole closure, but a relative scotoma was detected in 6 eyes. Of 6 eyes with partial closure, 1 had an absolute scotoma and 5 had a relative scotoma. An absolute scotoma was detected in 4 eyes with atrophic closure. CONCLUSIONS: After macular hole closure, SLO findings correlate both with biomicroscopic findings and foveal function. Better anatomical foveal recovery in eyes after macular hole closure results in better improvement of vision than in eyes in which the foveal anatomical findings are not as good.

Aged↗
PubMed2000

Effects of peroxynitrite on rabbit cornea.

BACKGROUND: Nitric oxide (NO) reacts rapidly with the superoxide anion to generate peroxynitrite, which has been found in the aqueous humor in eyes with uveitis. We evaluated the functional and anatomic effects of peroxynitrite on rabbit cornea. METHODS: One eye of each rabbit received an anterior chamber injection of 3-morpholinosydonimine N-ethylcarbamide (SIN-1), which simultaneously generates both NO and the superoxide anion. The corneal thickness was measured using an ultrasonic pachymeter before and after the injection. The eyes were fixed and the corneal specimens were prepared for electron microscopy. RESULTS: Anterior chamber injections of SIN-1 caused a significant increase in the corneal thickness (25.1+/-3.0 microm) 30 min after injection. Transmission electron microscopy showed swollen mitochondria and large vacuoles in the cytoplasm, and scanning electron microscopy revealed obscuring of the mosaic pattern by increased ruffling of endothelial cell surface and borders. CONCLUSION: The results suggest that peroxynitrite generated in the aqueous humor may cause corneal endothelial cell damage, which leads to transient corneal edema.

Animals↗
PubMed2000

[Burkitt's lymphoma occurring as a primary lymphomatous effusion].

A 39-year-old man was admitted with massive ascites. Specimens of ascitic fluid contained numerous cells with a FAB-L3 appearance, and small noncleaved cell lymphoma morphology. These cells expressed CD10, CD19, CD20, CD38, CD45, HLA-DR, and IgM antigens, and were positive for IgM and c-myc protein in cytoplasmic immunostaining tests. Clonal rearrangements of IgH and c-myc genes were detected by Southern blot analysis. No mass lesions were found by physical examination, and systemic computed photography did not reveal enlargement of lymph nodes, spleen, or liver. Bone marrow aspiration showed no infiltration of malignant cells. Ga scintigraphy indicated hot lesions only in the abdomen. These findings suggested that Burkitt's lymphoma had developed in the peritoneal cavity as a primary lymphomatous effusion. Chemotherapy with methotrexate, cyclophosphamide, vincristine, doxorubicin, etoposide, and dexamethasone was effective, and the patient has been free from the disease for 1 year since completion of consolidation treatment with autologous peripheral blood stem cell transplantation.

Adult↗
PubMed1999

Phenotypic consequence of the gene abnormality in the platelet glycoprotein IX gene observed in a patient with Bernard-Soulier syndrome through mammalian cell expression system.

We previously reported a patient with Bernard-Soulier syndrome (BSS) who had a homozygous missense mutation in the GPIX gene Phe55 (TTT) to Ser (TCT) replacement in the leucine-rich motif (LRM) of the GPIX polypeptide, as a probable cause of BSS phenotype. To study the effect of this mutation on the surface expression of the GPIb/IX complex and GPIX, we introduced this mutation into the cDNA of GPIX by site-directed mutagenesis and performed in vitro transfection studies with plasmid for mutant GPIX and other plasmids for GPIb/IX complex. Mutant GPIX could not increase the surface expression of GPIb-alpha, but also surface expression of GPIX itself. Immunostaining of the CHO-K1 cells transfected with two plasmids for mutant GPIX and GPIb-beta showed that mutant GPIX was weakly but certainly detected in the cytoplasm of the transfected cells. These findings indicate that this substitution is responsible for BSS phenotype and that the LRM of GPIX is a critically important element for an efficient expression of the GPIb/IX complex. They also suggest that the failure of GPIb/IX complex expression can be caused by a mechanism other than synthetic defect of the mutant protein.

Animals↗
PubMed1999

Interferon alfa receptor expression and growth inhibition by interferon alfa in human liver cancer cell lines.

Type I interferon (IFN) receptor consists of two chains (Hu-IFN-alphaR1 and Hu-IFN-alphaR2), and Hu-IFN-alphaR2 takes a soluble (Hu-IFN-alphaR2a), short (Hu-IFN-alphaR2b), or long (Hu-IFN-alphaR2c) form. We examined the expression of type I IFN receptor, the growth-suppression effect of IFN-alpha, and their relationship in 13 liver cancer cell lines. With reverse-transcription polymerase chain reaction (RT-PCR) analysis, the expressions of Hu-IFN-alphaR1, Hu-IFN-alphaR2a, and Hu-IFN-alphaR2c were confirmed in all cell lines, and that of Hu-IFN-alphaR2b in 12 cell lines. All cell lines expressed mRNAs of a transcriptional activator, interferon regulatory factor (IRF)-1, and its antagonistic repressor (IRF-2). Flow cytometry revealed weak expression of Hu-IFN-alphaR2 on the cell surface in 12 cell lines. The soluble-form protein of Hu-IFN-alphaR2 was detected at varying levels in culture supernatants of all cell lines with enzyme-linked immunosorbent assay (ELISA). Cell proliferation was suppressed in proportion to the dose of human natural IFN-alpha at 96 hours of culture, but it was not clearly related to the expression of Hu-IFN-alphaR2 protein on the cell surface. Investigations on the morphology, DNA, and cell cycle presented four growth suppression patterns as a result of IFN-alpha: 1) induction of apoptosis and blockage of cell cycle at the S phase (9 cell lines); 2) blockage at the S phase (2 cell lines); 3) induction of apoptosis and blockage at the G2/M phase (1 cell line); and 4) blockage at the G1 phase (1 cell line). There was no evidence showing that changes in the expressions of Bcl-2, Bcl-xL, Bak, and Bax lead directly to IFN-alpha-mediated apoptosis. Our findings demonstrated that IFN-alpha would express growth-suppression effects at varying degrees by inducing inhibition of cell-cycle progression with or without apoptosis, regardless of the expression level of Hu-IFN-alphaR2 protein on the cell surface.

Apoptosis↗
PubMed1999

Retinal detachment associated with a macular hole in severely myopic eyes.

PURPOSE: To investigate factors associated with extensive retinal detachment in severely myopic eyes with a macular hole. METHOD: Fifty-two consecutive eyes with a macular hole and severe myopia were retrospectively studied. RESULTS: An extensive retinal detachment, defined as extending beyond the cuff of subretinal fluid, was observed in 37 eyes (71%). Extensive retinal detachment developed in 36 (95%) of 38 eyes with a posterior staphyloma and in one (7%) of 14 eyes without a posterior staphyloma (P<.0001). Extensive retinal detachment also developed in 32 (89%) of 36 eyes with complete posterior vitreous detachment and in five (31%) of 16 eyes without posterior vitreous detachment (P<.0001). CONCLUSION: Posterior staphyloma rather than anteroposterior vitreomacular traction may contribute to the development of retinal detachment associated with a macular hole in severely myopic eyes.

Adult↗
PubMed1999

Posterior vitreous detachment induced by injection of plasmin and sulfur hexafluoride in the rabbit vitreous.

PURPOSE: To investigate whether an injection of plasmin and sulfur hexafluoride (SF6) can induce posterior vitreous detachment (PVD) without vitrectomy. METHODS: One eye each of 15 New Zealand white rabbits was assigned to one of three groups. Eyes in group 1 received a vitreous injection of 1 unit of human plasmin (0.1 mL reconstituted in balanced salt solution) and 0.5 mL of SF6; eyes in group 2 received a vitreous injection of plasmin alone; eyes in group 3 received a vitreous injection of SF6 alone. Seven days after injection, all animals were monitored electroretinographically and killed, and the eyes were enucleated. After fixation, scanning electron microscopy was performed. RESULTS: In group 1 eyes, the retinal surface was smooth except for the vitreous base, which showed complete separation of the vitreous cortex from the retina, indicating PVD. In group 2 and 3 eyes, sparse collagen fibers remained on the retinal surface. CONCLUSION: Vitreous injection of plasmin combined with SF6 can induce PVD without vitrectomy.

Animals↗
PubMed1999

Establishment and characterization of a new human hepatocellular carcinoma cell line, HAK-3, and its response to growth factors.

A new human hepatocellular (HCC) cell line, HAK-3, was established from a resected HCC of a Japanese, female patient. HAK-3 retains morphologic features of the original HCC, and proliferates in a monolayered sheet (doubling time: 26 h). HAK-3 is a single aneuploid cell population with a DNA index of 2.42, the karyotype is human, chromosomes are 80-85 (mode: 83), and secretes fibronectin and tissue polypeptide antigen. Epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF) dose-dependently accelerated the cell proliferation, while deletion-type hepatocyte growth factor (dHGF) tended to suppress the proliferation, and transforming growth factor (TGF)-alpha showed almost no influence. dHGF induced the decrease of cell adhesiveness, changed the cell morphology to spindle-shaped cells, increased cell movement, and showed chemotactic effects with the increase of its concentration gradient in cultures. HAK-3 would be useful in studies on the acceleration mechanisms of cancer cell proliferation by growth factors and of chemotaxis by dHGF.

Carcinoma, Hepatocellular↗
PubMed1998

Radiating retinal folds detected by scanning laser ophthalmoscopy using a diode laser in a dark-field mode in idiopathic macular holes.

BACKGROUND: The pathogenesis of idiopathic macular hole is unclear. We studied the morphologic features of idiopathic macular holes using a modification of the scanning laser ophthalmoscope (SLO). METHODS: Seventy-two eyes of 57 patients with macular hole (40 women, 17 men; age 66.1 +/- 6.4 years, mean +/- SD) were included in this study. The macular holes were classified according to the Gass classification (1988). The changes around the macular holes were recorded by SLO using both a confocal aperture with a helium-neon laser (633 nm) and a ring aperture (dark-field mode) with a diode laser (780 nm) to detect fine morphologic features. RESULTS: We successfully observed minute retinal wrinkling, i.e., radiating striae (fold type) and a dome configuration (dome type), around the macular holes using the SLO dark-field mode with a diode laser, which provides a deeper retinal image because of the longer wave-length laser and the indirect mode. A helium-neon laser with a confocal aperture sometimes failed to disclose the fine retinal wrinkles. Most of the stage 2 macular holes were of the fold type. The smaller the hole, the higher the prevalence of the fold type. As the holes progressed in size, the prevalence of the dome type increased. The radiating retinal folds disappeared after successful vitreous surgery. CONCLUSION: The SLO dark-field mode with a diode laser might be useful for clear observation of fine retinal features around macular holes. The retinal folds probably indicate the presence of traction on the macula and hence may be good markers for macular repair after vitreous surgery.

Aged↗
PubMed1998

Multiple inflammatory pseudotumors of the liver associated with acute myeloblastic leukemia.

A 26-year-old man, diagnosed with acute myelogenous leukemia had multiple inflammatory pseudotumors (IPT) in the liver. The patient presented complete remission after remission induction therapy, and then showed right upper quadrant discomfort and intermittent fever. An ultrasonography disclosed multiple hypoechoic nodules in the liver. A biopsy of the nodules showed focal liver cell necrosis with scant inflammatory cells, compatible with IPT. After several courses of chemotherapy, the nodules in the liver increased. The second liver biopsy of the nodule showed fibrosis. Multiple IPTs in the liver should be distinguished from abscess and metastatic nodules.

Adult↗