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T Nishida

Publications and source records attributed to T Nishida.

At least 163 records · Page 9Linked to original sources
PubMed1999

Galardin inhibits collagen degradation by rabbit keratocytes by inhibiting the activation of pro-matrix metalloproteinases.

We investigated the inhibitory action of a synthetic peptidyl hydroxamate inhibitor of matrix metalloproteinase (MMP), Galardin (GM6001), on collagen degradation by rabbit corneal stromal fibroblasts (keratocytes) cultured three-dimensionally in the type I collagen gel with medium containing interleukin 1alpha (IL-1alpha) and/or plasminogen. Degradation of collagen fibrils during culture was measured by the release of hydroxyproline, and activation of MMPs was also analyzed by gelatin zymography and Western blotting. Plasmin activity was measured using a synthetic substrate. In the absence of plasminogen, treatment of the cells with IL-1alpha in collagen gel greatly enhanced the production of proMMP-1, -3 and -9, but no significant degradation of collagen was detected. In the presence of plasminogen, IL-1alpha stimulated collagen degradation by keratocytes in a dose-dependent manner. This resulted from the plasminogen activator-plasmin system-dependent activation of proMMP-1, -3 and -9. Galardin inhibited the collagen degradation in a dose-dependent fashion in the presence of plasminogen, whether IL-1alpha was present or not. Galardin inhibited the activation of proMMP-3, and also prevented the activation of proMMP-9 and the conversion of MMP-1 intermediates to the fully active MMP-1. Galardin did not affect plasmin activity. The present results suggest that Galardin inhibits IL-1alpha-stimulated collagen degradation in the presence of plasminogen, resulting from not only inhibiting active MMPs but also preventing the conversion of proMMPs to active MMPs.

Animals↗
PubMed1999

Effect of galardin on collagen degradation by Pseudomonas aeruginosa.

The authors examined the effect of a synthetic peptidyl hydroxamate inhibitor of matrix metalloproteinase, Galardin, on collagen degradation by Pseudomonas aeruginosa (P. aeruginosa) in the presence or absence of keratocytes. Type I collagen gels, with or without suspended keratocytes, were incubated under medium containing sterile P. aeruginosa culture broth and/or Galardin for 24 hr. Degradation of collagen fibrils during culture was measured by the release of hydroxyproline. The conditioned media were also subjected to gelatin zymography and Western blotting to analyse the activation, by P. aeruginosa factor(s), of matrix metalloproteinases (MMPs) released by keratocytes. The effects of protease inhibitors, aprotinin, leupeptin and pepstatin, on collagen degradation by P. aeruginosa were also examined. P. aeruginosa broth by itself induced collegen gel degradation. When keratocytes were present, P. aeruginosa broth increased the amount of degraded collagen even further. Galardin significantly reduced the amounts of collagen degraded by P. aeruginosa culture broth, whether keratocytes were present or absent in the gel. However, the protease inhibitors had no inhibitory effects on collagen degradation. Gelatin zymography and Western blotting revealed that inactive proMMP-1, -2 and -3, released by keratocytes, were converted to active forms in the presence of P. aeruginosa broth. Galardin decreased the amounts of active MMPs and increased those of inactive proMMPs, suggesting that Galardin inhibited the activation of proMMPs by P. aeruginosa. The present results suggest that Galardin inhibits the keratocyte-mediated collagen degradation by P. aeruginosa culture broth, resulting from preventing the conversion of proMMPs to active MMPs.

Animals↗
PubMed1999

Solitary splenic recurrence of ovarian cancer: case report and review of the literature.

We report a rare case of solitary recurrence of ovarian cancer in the spleen which developed 4 years after initial treatment. Only six cases have been reported in the literature and all were serous carcinoma. Our patient had a splenectomy without any complications but developed a liver metastasis 10 months after splenectomy.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1999

Localization and ultrastructure of pulmonary dendritic cells during delayed-type hypersensitivity reactions in mice.

Dendritic cells (DCs) are widely distributed in the airways and can serve as potent antigen-presenting cells. To clarify their involvement in the cell-mediated immune responses of the lung, we immunohistochemically investigated their distribution and kinetics during pulmonary delayed-type hypersensitivity (DTH) reactions induced in sensitized mice by intratracheal instillation of hapten. Cellular infiltrate appeared around the bronchiole and its accompanying blood vessel at 12 h after elicitation and progressively expanded by 48 h. As quantitated by computer-assisted morphometry, I-A(+) DCs and CD4(+) Th cells significantly increased in number around the bronchiole to a maximum at 24 h, whereas F4/80(+) macrophages were predominantly accumulated around the accompanying vessel with a peak at 48 h. Serial-section analysis revealed that DCs were colocalized with Th cells in the inflamed peribronchiolar tissue. Immunoelectron microscopy demonstrated that DCs found inside and around the capillaries and venules of peribronchiolar interstitium displayed round forms, indicating their emigration from here, while those situated far from the microvessels were elongated, often in close apposition to the lymphocytes. Mitosis of DCs was rarely seen. The present results suggest that peribronchiolar accumulation of DCs resulting from accelerated influx of blood-borne immature DCs and the interaction with T cells at the application site may play inducing roles in the development of pulmonary DTH reactions by enhancing the recruitment of macrophages.

Animals↗
PubMed1999

Spermatogenic ability is different among males in different Y chromosome lineage.

It is a controversial question whether sperm concentrations in humans are changing. Several researchers have reported on environmental factors affecting sperm quality, but the influence of genetic factors is still not fully understood. In this study, we examined the relationship between Y chromosome haplotypes and sperm concentration in fertile males. In addition, we determined the haplotypes of azoospermic patients. The results show that the mean sperm concentration correlates with Y chromosome type. Moreover, the occurrence of azoospermia is related to one particular Y chromosome lineage. Thus, males with a certain haplotype are at a disadvantage for fathering children. The difference of spermatogenic ability among men is important not only in pursuing male competition as in the past but also as relates to the future of modern human males.

Fertility↗
PubMed1999

Biliary bacterial infection decreased the secretion of bile acids and bilirubin into bile.

BACKGROUND: Bacterial cholangitis is frequently associated with serious complications. METHODS: The plasma disappearance rates and the biliary output of bile acids and bilirubin after percutaneous transhepatic biliary drainage (PTBD) were examined in 29 patients with extrahepatic biliary obstruction. RESULTS: Twenty-nine patients were divided into the bacteria-minus (n = 17) and bacteria-plus (n = 12) groups. Decreases in the plasma bile acid and bilirubin levels of the bacteria-minus group (t1/2 = 0.38 and 3.8 days for bile acids and bilirubin, respectively) were faster than those of the bacteria-plus group (t1/2 = 1.7 and 7.5 days). The bile flow rate was significantly increased in the bacteria-plus group compared with the bacteria-minus group. The calculated values of bilirubin and bile acid in the bile were higher in the bacteria-minus group than in the bacteria-plus group. CONCLUSIONS: Bacterial colonization in the bile stimulates bile duct cells to increase bile volume and inhibits the hepatocyte transport activity of bile acids and bilirubin.

Aged↗
PubMed1999

Activation of Kupffer cells and caspase-3 involved in rat hepatocyte apoptosis induced by endotoxin.

BACKGROUND/AIMS: Sepsis and lipopolysaccharides (LPS) cause mild to severe hepatic dysfunction. In this study, Kupffer cell activation, involvement of TNFalpha and caspases downstream of the TNFalpha receptor were examined in hepatocyte apoptosis induced by LPS. METHODS: In in vivo experiments, male Sprague-Dawley rats were injected intravenously with LPS, and small amounts of the blood and liver were sampled to evaluate apoptosis. Kupffer cells were inactivated by pretreatment with gadolinium chloride for 2 days. In in vitro experiments, hepatocytes and Kupffer cells were separately isolated from rat livers using collagenase perfusion. RESULTS: LPS induced time-dependent and dose-dependent increases in the number of TUNEL-positive cells, which coincided with the apoptotic features of hepatocytes demonstrated by electron microscopy and DNA ladder. Activation of caspase-3-like proteases was observed with an increase in the number of apoptotic hepatocytes. Immunostaining with activated caspase-3-specific antibody showed that caspase-3 was activated only in the cytoplasm of TUNEL-positive hepatocytes. Inactivation of Kupffer cells by gadolinium chloride was concomitantly accompanied by the prevention of caspase-3 activation, hepatocyte apoptosis and liver injury induced by LPS. The co-culture system of hepatocytes and Kupffer cells, but neither cell culture system, individually, showed LPS-induced hepatocyte apoptosis. Kupffer cell-conditioned medium induced hepatocyte apoptosis, whereas addition of anti-TNFalpha antibody to Kupffer cell-conditioned medium did not. Additions of acetyl-DEVD-CHO, acetyl-YVAD-CHO, and acetyl-IETD-CHO to Kupffer cell-conditioned medium decreased the number of apoptotic hepatocytes. CONCLUSIONS: These results suggest that the activation of Kupffer cells, TNFalpha and caspases downstream of TNFR1 were involved in hepatocyte apoptosis induced by LPS.

Alanine Transaminase↗
PubMed1999

Variable-speech-rate audiometry for hearing aid evaluation.

A new hearing aid evaluation method using variable-speech-rate audiometry (VSRA) was developed. VSRA was newly created based on the Japanese speech audiometry authorized by the Japan Audiological Society. The ordinary speech audiometry can not reveal a temporal factor in word discrimination ability of the hearing impaired. Since, with VSRA, we can compare several performance-intensity curves obtained from different speech-rate speech audiometries, the impact on the auditory system of each patient by the fast or slow speech rate could be easily determined. Taking the temporal factor of the auditory systems into consideration by using VSRA, hearing aid evaluation was performed for a master hearing aid with three types of signal processing and fitting for 36 hearing impaired subjects. Then hearing aid evaluation was performed using VSRA for a newly developed portable multi-function digital hearing aid with two types of signal processing and analog hearing aids which had been used by hearing-impaired patients. As a result, VSRA was useful for hearing aid evaluation, in particular, for cases when ordinary normal speech rate audiometry does not provide a significant difference in word discrimination scores. In addition, using VSRA revealed that amplitude compression is more effective for improvement of word discrimination than linear amplification.

Adolescent↗
PubMed1999

Combination therapy with irinotecan and cisplatin as neoadjuvant chemotherapy in locally advanced cervical cancer.

To evaluate the response rate and toxicity of the combination of irinotecan (CPT-11) and cisplatin in a neoadjuvant setting, a phase II study was conducted regarding the regimen of this combination in patients with locally advanced cervical cancer. Eligibility included patients with previously untreated stage Ib2, IIb, or IIIb squamous cell carcinoma with good performance status. CPT-11 (60 mg m(-2)) was administered intravenously on days 1, 8 and 15, followed by cisplatin (60 mg m(-2)) given intravenously on day 1. Treatment was repeated every 4 weeks for a total of two or three cycles. Among 23 eligible patients (median age: 59 years), three showed complete response (13%), 15 showed partial response (65%), for an overall response rate of 78% (95% confidence interval 58-90%). Stable disease was observed in four cases (17%) and progressive disease in one (4%). The median time to failure and median survival time have not yet been reached. Of the 52 treatment cycles administered, diarrhoea and grade 3 or 4 neutropenia were observed in 10% and 75% respectively. There were no therapy-related deaths. The combination of CPT-11 with cisplatin is a promising regimen for neoadjuvant chemotherapy in locally advanced cervical cancer. The toxicities of this regimen are well tolerated.

Adult↗
PubMed1999

Synergistic effect with Phe-Gly-Leu-Met-NH2 of the C-terminal of substance P and insulin-like growth factor-1 on epithelial wound healing of rabbit cornea.

1. We previously reported that substance P and insulin-like growth factor-1 (IGF-1) synergistically stimulate corneal epithelial wound healing in vitro and in vivo. We wished to identify which portion of the amino acid sequence of substance P might be responsible for this synergism. 2. Corneal epithelial migration was not affected by the addition of any one of the following factors: substance P; Phe-Gly-Leu-Met-NH2 (C-terminal of substance P); Val-Gly-Leu-Met-NH2 (C-terminal of neurokinin A, neurokinin B, and kassinin); Tyr-Gly-Leu-Met-NH2 (C-terminal of physalaemin); Ile-Gly-Leu-Met-NH2 (C-terminal of eledoisin); or Gly-Leu-Met-NH2 (common C-terminal of tachykinins). 3. In the presence of IGF-1, only substance P and Phe-Gly-Leu-Met-NH2 were synergistic in stimulating corneal epithelial migration in a dose-dependent fashion. 4. The combination of Phe-Gly-Leu-Met-NH2 and IGF-1 did not affect the incorporation of [3H]-thymidine into corneal epithelial cells. 5. Treatment with Phe-Gly-Leu-Met-NH2 and IGF-1, but not with Phe-Gly-Leu-Met-NH2 or IGF-1 alone, increased attachment of corneal epithelial cells to a fibronectin matrix. 6. The levels of alpha5 and beta1 integrin were not affected by Phe-Gly-Leu-Met-NH2 or IGF-1 alone, but they were significantly increased by the combination of Phe-Gly-Leu-Met-NH2 and IGF-1. 7. Topical application of the same combination facilitated corneal epithelial wound closure in vivo. 8. These results demonstrated that Phe-Gly-Leu-Met-NH2, a sequence of 4 amino-acids of the C-terminal of substance P, is the minimum sequence necessary to produce the synergistic effects of substance P and IGF-1 on corneal epithelial wound healing.

Administration, Topical↗
PubMed1999

A new preconditioning regimen with melphalan, busulphan and total body irradiation followed by low-dose immunosuppressant in allogeneic haemopoietic stem cell transplantation.

Twenty adult patients with high-risk leukaemia underwent allogeneic haemopoietic stem cell transplantation after melphalan, busulphan and total body irradiation followed by short-term methotrexate and low-dose cyclosporine or tacrolimus. Three patients developed veno-occlusive disease and no patient developed renal dysfunction. Seven patients experienced grade II-IV acute graft-versus-host disease (aGVHD) and five patients experienced grade III-IV. The 3-year probabilities of relapse and leukaemia-free survival were 22 +/- 11% (95% confidence interval) and 50 +/- 11%, respectively. These data suggest that this preconditioning regimen followed by a low-dose immunosuppressant provided a more anti-leukaemic effect without increased regimen-related toxicity and aGVHD.

Adult↗
PubMed1999

Secretion of phospholipid transfer protein by human hepatoma cell line, Hep G2, is enhanced by sodium butyrate.

Hep G2 cells were used to study the synthesis and secretion of phospholipid transfer protein (PLTP). Upon incubation of the cells at confluence with serum-free Dulbecco's modified Eagle's medium (DMEM), phosphatidylcholine (PC) transfer activity was found to accumulate in the culture media. The PC transfer activity in the media was effectively inhibited by rabbit anti-human PLTP immunoglobulin (Ig)G, thus indicating that the PC transfer activity was due to secreted PLTP. The molecular weight of Hep G2 PLTP was approximately 78 kDa by Western blot analysis, in agreement with the molecular weight obtained for purified human plasma PLTP. The PLTP secreted by Hep G2 also possessed an HDL conversion activity similar to that of human plasma PLTP. The addition of butyrate to the cell culture media resulted in a marked increase in the secretion of PLTP. After 24 h incubation with 4 mmol/L sodium butyrate, a more than twofold increase (P < 0.01) of PC transfer activity in the cell-conditioned media was obtained. The dose-dependent increase in the PC transfer activity in the media upon butyrate treatment was well correlated (r = 0.80, P < 0.01) with that of PLTP mass as determined by immuno-slot blot analysis of cell-conditioned media. The increased secretion of PLTP by Hep G2 treated with sodium butyrate was accompanied by a greater increase in the level of PLTP mRNA in the cells as determined by ribonuclease protection assay. In the presence of 4 mmol/L sodium butyrate, a fourfold increase (P < 0. 01) in mRNA level was obtained at 24 h. No stabilizing effect of butyrate on PLTP mRNA was apparent upon treatment of the cultured cells with the RNA synthesis inhibitor, actinomycin D. Thus, the up-regulatory effect of butyrate on PLTP gene expression seemed to have occurred at the transcriptional level.

Animals↗
PubMed1999

Connective tissue growth factor induces the proliferation, migration, and tube formation of vascular endothelial cells in vitro, and angiogenesis in vivo.

Connective tissue growth factor (CTGF) is a novel cysteine-rich, secreted protein. Recently, we found that inhibition of the endogenous expression of CTGF by its antisense oligonucleotide and antisense RNA suppresses the proliferation and migration of vascular endothelial cells. In the present study, the following observations demonstrated the angiogenic function of CTGF in vitro and in vivo: (i) purified recombinant CTGF (rCTGF) promoted the adhesion, proliferation and migration of vascular endothelial cells in a dose-dependent manner under serum-free conditions, and these effects were inhibited by anti-CTGF antibodies; (ii) rCTGF markedly induced the tube formation of vascular endothelial cells, and this effect was stronger than that of basic fibroblast growth factor or vascular endothelial growth factor; (iii) application of rCTGF to the chicken chorioallantoic membrane resulted in a gross angiogenic response, and this effect was also inhibited by anti-CTGF antibodies. (iv) rCTGF injected with collagen gel into the backs of mice induced strong angiogenesis in vivo. These findings indicate that CTGF is a novel, potent angiogenesis factor which functions in multi-stages in this process.

Allantois↗
PubMed1999

Clinicopathological significance of poorly differentiated thyroid carcinoma.

The clinicopathological importance of a heterogeneous group of poorly differentiated thyroid carcinomas is not fully understood. Using data obtained from 303 surgically treated patients with differentiated thyroid carcinomas, the correlations between the aggressive histologic features and the clinicopathological findings, postoperative recurrences, and prognosis were retrospectively examined. In 201 cases, the carcinomas were well differentiated. The remaining 102 cases of poorly differentiated carcinomas were divided into two groups: focal-poorly differentiated (<10%) and diffuse-poorly differentiated (> or = 10%) carcinomas according to the extent of the poorly differentiated component. These poorly differentiated carcinomas were associated with high age (focal-poorly differentiated and diffuse-poorly differentiated versus well differentiated: 55 years and 59 versus 49; p < 0.0001), frequent presence of lymph node metastases (70% and 66% versus 48%; p = 0.0099) and distant metastases at diagnosis (11% and 11% versus 2%; p = 0.0098), and extrathyroidal invasion (53% and 53% versus 21%; p < 0.0001). There was independent correlation with age and the presence of extrathyroidal invasion. Cases of diffuse-poorly differentiated carcinomas showed frequent relapse (diffuse-poorly differentiated versus focal-poorly differentiated and well differentiated: 45% versus 30% and 24%; p = 0.0062) and poor prognoses (mean survival period = 9.15 versus 19.03 and 20.87 years; p < 0.0001) compared with the well and focal-poorly differentiated carcinomas. These data suggest that diffuse-poorly differentiated carcinoma is an important clinicopathological entity.

Adenocarcinoma, Follicular↗
PubMed1999

Differential effects of epidermal growth factor and interleukin 6 on corneal epithelial cells and vascular endothelial cells.

PURPOSE: Epidermal growth factor (EGF) and interleukin 6 (IL-6) stimulate corneal epithelial wound healing. When applied to the cornea, these cytokines act on various types of cells and therefore may induce corneal neovascularization. We investigated the effects of EGF and IL-6 on cell proliferation and cell migration in rabbit corneal epithelial cells and human umbilical vein endothelial cells (HUVECs). METHODS: Corneal epithelial cells or HUVECs were cultured with EGF or IL-6 in the presence of 1% fetal bovine serum, and the number of cells were counted, or the radioactivity of [3H]thymidine-incorporated cells was measured. Monolayered cultured corneal epithelial cells or HUVECs were mechanically wounded, and then the cells were cultured with serum-free basal medium containing EGF or IL-6. After 12 or 24 h, the wounded area was measured. Corneal blocks were cultured with serum-free TC-199 medium containing EGF or IL-6 for 24 h, and then the length of the path of the corneal epithelium was measured. RESULTS: Estimated cell count and [3H]thymidine uptake showed that EGF stimulated cell proliferation in both corneal epithelial cells and HUVECs in a dose-dependent manner. In contrast, IL-6 did not affect cell proliferation in either cell type. Furthermore, EGF also stimulated cell migration by increasing the monolayer and organ-culture system in both cells in a dose-dependent fashion. However, IL-6 stimulated cell migration only in corneal epithelial cells and not in HUVECs. CONCLUSION: These results demonstrated that EGF stimulated cell proliferation and migration in both corneal epithelial cells and HUVECs. In contrast, IL-6 stimulated only corneal epithelial cell migration and did not affect cell proliferation in either cell type or cell migration in HUVECs. These results suggest that, when applied to the cornea, EGF might induce corneal neovascularization, and IL-6 probably would not.

Animals↗
PubMed1999

Synergistic effects of hyaluronan and fibronectin on epithelial migration in rabbit cornea in vitro.

PURPOSE: We investigated the interactions of hyaluronan with extracellular matrix proteins (fibronectin, laminin, and type IV collagen) on corneal epithelial migration by using an organ-culture system of rabbit corneas. METHODS: Rabbit corneal blocks were cultured in the absence or presence of various reagents for a total of 20 h. The corneal blocks were then fixed, dehydrated, embedded in paraffin, and stained by hematoxylineosin, and the length of the path of epithelial migration was measured. RESULTS: The addition of hyaluronan, fibronectin, or type IV collagen alone stimulated epithelial migration in a dose-dependent manner, but laminin did not. When corneal blocks were pretreated with extracellular matrix proteins (fibronectin, laminin, or type IV collagen) for 5 h and then were cultured for 15 h with hyaluronan, only pretreatment with fibronectin demonstrated a synergistic effect with hyaluronan on corneal epithelial migration. In contrast, when corneal blocks were pretreated with hyaluronan for 5 h and then cultured for 15 h with extracellular matrix proteins, the additive effects of hyaluronan with fibronectin or hyaluronan with type IV collagen were observed. The synergistic effects of hyaluronan and fibronectin on corneal epithelial migration were partially inhibited by the addition of antiserum against fibronectin. In contrast, the addition of antiserum against fibronectin receptor completely inhibited the synergistic effects of hyaluronan and fibronectin on epithelial migration. CONCLUSION: These results suggest that hyaluronan and fibronectin have a synergistic effect, with fibronectin pretreatment augmenting hyaluronan-stimulated corneal epithelial migration.

Animals↗
PubMed1999

Synthesis and antifungal activities of (2R,3R)-2-aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives as topical antifungal agents.

2-Aryl-1-azolyl-3-(substituted amino)-2-butanol derivatives I were prepared by ring-opening reaction of epoxides II with excess amine, and their antifungal activities were evaluated as topical agents. Azolyl-cyclic amine derivatives with a methylene group showed extremely strong activity with a broad spectrum in vitro. In general, anti-Trichophyton mentagrophytes activities of most of the topical antifungal agents are substantially reduced by addition of keratin (a major constituent of the keratinized tissue). However, the triazole derivative (2R,3R)-2-(2,4-difluorophenyl)-3-(4-methylenepiperidino)-1-(1H-1,2 ,4- triazol-1-yl)-2-butanol ((-)-40, KP-103) showed very little deactivation by addition of keratin. This biological characteristic of triazole derivative (-)-40 resulted in excellent therapeutic efficacy on dermatophytosis superior to that of the corresponding imidazole derivative ((-)-41).

Animals↗