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Biomedical subjects

T Itoh

Publications and source records attributed to T Itoh.

At least 253 records · Page 14Linked to original sources
PubMed2000

Enhanced neutrophilic granulopoiesis in rheumatoid arthritis. Involvement of neutrophils in disease progression.

OBJECTIVE: To investigate enhanced granulopoiesis in bone marrow of patients with rheumatoid arthritis (RA), and the role of neutrophils in RA pathogenesis. METHODS: Aspirated bone marrow cells and peripheral blood leukocytes from patients with RA and non-RA patient controls were analyzed morphologically and by 2 color flow cytometry. Thirteen iliac bones (8 RA, 5 non-RA) were examined by light and transmission electron microscope (TEM). RESULTS: The percentage of CD15+CD16- cells (immature neutrophils) in RA bone marrow (64.3+/-13.4%, mean +/- SD) increased significantly compared to that of non-RA controls (43.2+/-14.3%), whereas the fraction of CD15+CD]6+ cells (mature neutrophils)was greatly decreased (RA 21.8+/-10.1%; non-RA 38.1+/-8.9%). The absolute number of CD15+CD16- cells also increased markedly in RA bone marrow. The ratio of immature cells to the total granulocytes (% CD15+CD16- to % CD15+) correlated with the Lansbury Index score (R = 0.76, p<0.0001). TEM observations revealed that abundant immature neutrophils adhered closely to the trabeculae of the iliac bone. Margins of trabeculae were mostly irregular, especially in severe RA, and collagenous fibers frequently disappeared in those trabeculae with ragged margins. CONCLUSION: In RA bone marrow, immature neutrophils (CD15+CD16-) were markedly increased in number; by contrast, no changes were found for mature cells. Augmented production of immature neutrophils (at the promyelocyte-to-myelocyte stage) might lead to the destruction of collagenous fibers in RA bone trabeculae, as revealed by TEM. Generalized bone destruction in RA might, at least in part, be caused by enhanced production of immature neutrophils.

Adult↗
PubMed2000

Diminished calcium homeostasis and increased susceptibility to excitotoxicity of JS 3/16 progenitor cells after differentiation to oligodendroglia.

JS 3/16, derived from passaged oligodendroglial cultures prepared from rat cerebral white matter, differentiate from progenitors (OP) into complex process-bearing, galactocerebroside-positive but myelin basic protein-negative immature oligodendrocyte-like cells (ImO) after withdrawal of trophic factors. We found that JS 3/16 ImO are markedly more susceptible than OP to cell death after sustained alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate glutamate receptor (AMPA-GluR) activation. This excitotoxicity is preceded by loss of intracellular Ca(2+) homeostasis, which is more marked in ImO than OP. We identified three factors likely to contribute to the diminished Ca(2+) homeostatic capacity of ImO. First, signal intensities of immunoreactive GluR2, GluR3, and GluR4 AMPA-GluR subunits are increased 1.3- to 2.2-fold in ImO over OP without comparable changes in RNA editing and alternative splicing. Second, transcriptional levels of genes encoding Na(+)-Ca(2+) exchanger proteins and a plasma membrane ATPase (PMCA1), which are necessary for Ca(2+) extrusion across the plasma membrane, are lower in ImO than in OP. Third, ImO have more depolarized basal mitochondrial membrane potential (Delta Psi) than OP, and Delta Psi collapses within 15 min after onset of AMPA-GluR activation in almost all ImO, but not in the majority of OP. This Delta Psi collapse limits the capacity of ImO mitochondria to buffer the rise in intracellular Ca(2+) caused by AMPA-GluR activation. The JS 3/16 line provides a valuable system for analysis of intracellular Ca(2+) homeostasis and AMPA-GluR-mediated excitotoxicity in the oligodendroglial lineage.

Animals↗
PubMed2000

Relationship between p53 overexpression and the proliferative activity in hepatocellular carcinoma.

Relationship between p53 protein overexpression and clinicopathological findings and the proliferative activity was studied in 50 cases of hepatocellular carcinoma (34 biopsy and 16 surgically resected cases) using immunohistochemistry. Overexpression of p53 was observed in 26.5% of biopsy cases and 31. 3% of surgically resected cases. Investigation of the relationship between the p53-positive rate and the clinical stage of HCC showed that it was significantly higher in Stage IV (the most advanced cancer; 54.5%) than in Stage I/II/III (13.0%) (p<0.05). Examination of the relationship between the p53-positive rate and tumor differentiation in the biopsy cases showed that p53 was positive in 9.1% of well differentiated carcinomas, 21.4% of moderately differentiated carcinomas, and 55.6% of poorly differentiated carcinomas, indicating that p53 positivity increased as tumors became less differentiated. The p53-positive rate of poorly differentiated carcinoma (55.6%) was significantly higher than that of well and moderately differentiated carcinoma (16.0%) (p<0.05). In the surgically resected cases, p53 overexpression tended to be more frequent in the less differentiated parts of each tumor nodule. In cases with nodule in nodule pattern of HCC, the p53-positive rate was different among nodules with the same level of differentiation. Examination of tumor cell proliferative activity using the proliferating cell nuclear antigen L.I. showed that this indicator was significantly higher in the p53-positive tumors than in the p53-negative tumors (52.7+/-32.4% vs. 32.4+/-15.3%: p<0.05). These results suggest that p53 overexpression may be involved in determining the dedifferentiation and the proliferative activity of HCC. Examination of the surgically resected cases confirmed that p53 overexpression became heterogeneous during the multistep carcinogenesis and growth process of HCC, which is considered to develop from a single cell. This finding suggests that p53 overexpression may be involved in tumor progression.

Aged↗
PubMed2000

[Sphincter-preserving surgery for lower rectal cancer aimed at improving postoperative bowel function].

Much attention has been focused on sphincter-preserving surgery for patients with lower rectal cancer, leading to renewed interest in the outcome of postoperative bowel function. Some patients who undergo sphincter-preserving surgery experience bowel dysfunction, such as frequent stools, severe constipation, soiling, and incontinence. These symptoms were thought to be correlate with lower resting pressure, lower rectal compliance, sensory disturbance of the anal canal, spasm, and delayed transit in the colon above the anastomosis. To improve postoperative bowel function, reconstruction with the colonic J-pouch has been performed, which results in a satisfactory functional outcome. About 80% of patients with a J-pouch were able to tolerate over 10 minutes after feeling the desire to defecate. An anorectal manometric study showed no abnormal spastic movement of the neorectum and a transit study showed that the J-pouch group was superior to the straight group with respect to the smoothness of movement of radiopaque markers from the cecum to anal ring, although a small number of markers were retained in the colonic J-pouch. Patients who received a colonic J-pouch had fewer defecation problems in daily life. Further study is need to improve postoperative bowel movement in patients who undergo sphincter-preserving surgery.

Anal Canal↗
PubMed2000

[Bellini duct carcinoma of the kidney: a case report].

This is a report of a case of Bellini duct carcinoma of the kidney. A 72-year-old male was admitted to our hospital for the treatment of left renal tumor. The abdominal computed tomographic scan showed hypoattenuating tumor with infiltrative spread into the renal cortex. The renal angiography revealed a hypovascular tumor. Left nephro-ureterectomy was performed because transitional cell carcinoma was suspected in the frozen section. The gross examination revealed an infiltrating white-gray tumor centered in the renal medulla. No hemorrhage was discovered, but partial necrosis was found. Capsular infiltration was not seen. Histologically, tumor cells were mostly scattered and partially showed a papillary and tubular structure. Cells had abundant eosinophilic cytoplasm and large irregular nuclei. Immunohistochemical studies revealed positive reactions for cytokeratin, epithelial membrane antigen and ulex europaeus agglutinin. We diagnosed this patient with Bellini duct carcinoma. He died due to drastic progression of metastasis from carcinoma two months postoperatively.

Aged↗
PubMed2000

[A study on the appropriate time point for the assessment of Helicobacter pylori eradication--evaluation from the re-positive rate of H. pylori after successful eradication and delayed decrease of 13C-urea breath test levels].

We attempted to evaluate the appropriate time point for the assessment of Helicobacter pylori eradication after treatment. One hundred and nine patients with gastroduodenal diseases were enrolled this study. All of them were received proton pomp inhibitor based triple therapy and diagnosed as eradication of H. pylori infection at initial assessment. They were followed up over six months. The diagnosis of H. pylori eradication was determined by rapid urease test, culture, histology and 13C-urea breath test (UBT), and the initial assessment of the eradication was performed on 31-90 days after finishing eradication therapy. Re-appearance rate of H. pylori after initial diagnosis of eradication was 4.6% (5/109), and the mean follow-up period of them was 16.3 months. The time period of initial assessment of eradication in these 5 patients were 35, 37, 42, 49 and 60 days after treatment, respectively. On the other hand, there were 6 patients who were diagnosed as failed of eradication therapy by 13C-UBT, and being success at following period. All of the 13C-UBT levels of these 6 patients were less than 10/1000 and were decreased within negative range subsequently. The time periods of initial diagnosis of these patients except one were within 2 months after treatment. It was concluded that the assessment time of H. pylori eradication should be performed over 2 months after eradication therapy.

Adult↗
PubMed2000

[Locoregional adoptive immunotherapy using LAK cells and IL-2 against liver metastases from digestive tract cancer].

We investigated the clinical efficacy of locoregional and systemic adoptive immunotherapy (AIT) with or without interleukin-2 (IL-2) against solid metastatic lesions from digestive tract cancer. Eighteen patients, who were treated with more than 10(10) lymphokine-activated killer (LAK) cells, were enrolled in this study. Seven of the 18 patients received hepatic arterial infusion (HAI) of LAK cells with or without IL-2 against metastatic liver tumors (locoregional therapy group). The remaining 11 patients received systemic transfer of LAK cells with IL-2 against metastatic lesions located in organs other than the liver (systemic therapy group). Three of 7 locoregional therapy group patients showed clinically significant tumor regressions that were evaluated as being equivalent to partial response (PR). Two of the 11 systemic therapy group patients showed significant tumor regressions, but this response rate was much lower than that of the locoregional therapy group. The 2 effective cases in the systemic therapy group were esophageal cancer patients. Locoregional AIT with or without IL-2 against liver metastases from digestive tract cancer could be an effective therapeutic modality in some patients who are refractory to conventional therapies (e.g., chemotherapy and radiotherapy). It is necessary to find a new way to augment the anti-tumor effect of this therapy in combination with prior or concomitant chemotherapy.

Adult↗
PubMed2000

Experimental use of a compact centrifugal pump and membrane oxygenator as a cardiopulmonary support system.

Compactness and high performance are the most important requirements for a cardiopulmonary support system. The Nikkiso (HPM-15) centrifugal pump is the smallest (priming volume; 25 ml, impeller diameter; 50 mm) in clinically available centrifugal pumps. The Kuraray Menox (AL-2000) membrane oxygenator, made of double-layer polyolefin hollow fiber, has a minimum priming volume (80 ml) and a low pressure loss (65 mm Hg at 2.0 L/min of blood flow) compared with other oxygenators. The aim of this study was to evaluate the performance of the most compact cardiopulmonary support system (total priming volume: 125 ml) in animal experiments. The cardiopulmonary bypass was constructed in a canine model with the Nikkiso pump and Menox oxygenator in comparison with a conventional cardiopulmonary support system. The partial cardiopulmonary bypass was performed for 4 h to evaluate the gas exchange ability, blood trauma, serum leakage, hemodynamics, and blood coagulative parameters. The postoperative plasma free hemoglobin level of the compact cardiopulmonary system was 29.5 +/- 10.21 mg/dl (mean +/- SD), which was lower than that of the conventional cardiopulmonary system, 48.75 +/- 27.39 mg/dl (mean +/- SD). This compact cardiopulmonary system provided the advantage in terms of reduction of the priming volume and less blood damage. These results suggested the possibility of miniaturization for the cardiopulmonary bypass support system in open-heart surgery in the near future.

Animals↗
PubMed2000

Gross and microscopic anatomy of the extraorbital lacrimal gland of the common marmoset (Callithrix jacchus).

PURPOSE: The lacrimal gland is often selected for microscopic examination in toxicologic studies. However, this gland is difficult to find within the orbit in marmosets at necropsy. Therefore, we examined the extraorbital lacrimal glands in marmosets. METHODS: The formalin-fixed craniums of four marmosets were used in a topographic study to confirm location of the lacrimal gland, and the results were applied to a routine toxicologic study in marmosets. RESULTS: The extraorbital lacrimal gland was located on the temporal surface of the zygomaticofrontal process and was covered with the temporalis muscle. The gland was easily detached from the surrounding tissue, and its histologic features were the same as those of the intraorbital lacrimal gland. CONCLUSIONS: The extraorbital lacrimal glands have been reported in some New World monkeys, but to the authors' knowledge, this is the first report in marmosets. Identification and characterization of this gland will be useful for toxicologic studies in marmosets.

Animals↗
PubMed2000

Bond strength of brackets cemented with light-cured glass-ionomer cements to contaminated enamel.

PURPOSE: To examine the effect of contamination on the bond strength of orthodontic brackets cemented with either a commercial (Fuji Ortho LC) or an experimental light-cured glass-ionomer cement to enamel, and the effect of etching times on the bond strength. MATERIALS & METHODS: Simulated metal brackets were applied with the cements to bond polished and etched (37% phosphoric acid) bovine enamel with and without contamination by water, human saliva, and blood. After 1-day water immersion, the shear bond strengths were measured. The fractured surfaces were examined using SEM. Additional tests were conducted on: (1) the Knoop hardness of the contaminated cements, (2) the HEMA composition of the cements, (3) the viscosity of the cements, and (4) the intensity of transmitted visible light through the contaminants. The results were compared by ANOVA and Duncan's tests at P=0.05. RESULTS: Water and saliva reduced the bond strength to polished and etched enamel, except for the bond strength of Fuji Ortho LC to polished enamel. The blood contamination produced poor bond strengths to polished and etched enamel. The experimental cement showed higher bond strengths to polished enamel with water and saliva contamination than Fuji Ortho LC. The bond strength of the experimental cement to etched enamel with and without contamination were comparable to those of Fuji Ortho LC. SEM micrographs revealed that the specimens exhibiting high bond strengths to polished and etched enamel mainly had cement-enamel interface failure and cement-metal mesh interface failure, respectively. Fuji Ortho LC had higher HEMA concentration than the experimental cement. The highest viscosity was measured with blood, followed by saliva and water. Blood contamination, showing the highest attenuation of the light intensity, reduced Knoop hardness of the experimental cement and Fuji Ortho LC.

Acid Etching, Dental↗
PubMed2000

The effects of visual input on postural control mechanisms: an analysis of center-of-pressure trajectories using the auto-regressive model.

New measures to characterize center-of-pressure (COP) trajectories during quiet standing were proposed and then utilized to investigate changes in postural control with respect to visual input. Eleven healthy male subjects (aged 20-27 years) were included in this study. An instrumented force platform was used to measure the time-varying displacements of the COP under each subject's feet during quiet standing. The subjects were tested under eyes-open and eyes-closed conditions. The COP time series were separately analyzed for the medio-lateral and antero-posterior directions. The proposed measures were obtained from the parameter estimation of auto-regressive (AR) models. The percentage contributions and geometrical moment of AR coefficients showed statistically significant differences between vision conditions. The present COP displacements under the eyes-open condition showed higher correlation with the past COP displacements at longer lag times, when compared to the eyes-closed condition. In contrast, no significant differences between vision conditions were found for conventional summary statistics, e.g., the total length of the COP path. These results suggest that the AR parameters are useful for the evaluation of postural stability and balance function, even for healthy young individuals. The role of visual input in the postural control system and implications of the findings were discussed.

Adult↗
PubMed1999

Effect of Shimotsu-to (a Kampo medicine, Si-Wu-Tang) and its constituents on triphasic skin reaction in passively sensitized mice.

Previous studies have reported that mice passively sensitized with anti-DNP (dinitrophenol) IgE antibody exhibited IgE-mediated skin reaction with an immediate phase response (IPR) at 1 h and a late phase response (LPR) at 24 h after the challenge of DNFB (dinitrofluorobenzene). We recently found that a third phase inflammatory reaction with intense and persisting infiltration of eosinophils, named very late phase response (vLPR), was induced by DNFB challenge peaking at 8 days. In this study, we examined the effects of a Kampo medicine, Shimotsu-to (Si-Wu-Tang), and its constituent crude drugs on triphasic skin reaction in passively sensitized mice. Shimotsu-to inhibited ear swelling in LPR and vLPR after DNFB challenge in a dose-dependent manner, and slightly diminished the scratching behavior considered to be associated with pruritus in IPR. The inhibitory effect on LPR and vLPR was partly due to Cnidii Rhizoma (Senkyu) in Shimotsu-to formulation, especially its fraction 5 containing cnidilide. On the other hand, Angelicae Radix (Toki) rather than Cnidii Rhizoma (Senkyu) in Shimotsu-to, inhibited the scratching behavior, although it did not inhibit the ear swelling in IPR. These findings indicate that the Shimotsu-to formulation is useful for the inhibition of cutaneous inflammatory diseases.

Animals↗
PubMed1999

Reduction of tyrosine kinase B and tyrosine kinase C inductions by treatment with neurotrophin-3 after transient middle cerebral artery occlusion in rat.

Infarct volume and immunoreactivities for trkB and trkC in rat brain were compared at 24 h after 90 min of transient middle cerebral artery occlusion (MCAO) between animal groups with or without neurotrophin-3 (NT-3, 10 microg/250 g animal). Treatment of rat brain with topical application of NT-3 significantly reduced infarct volume (P = 0.02) and trkB and trkC inductions. These data suggest that NT-3 reduced the ischemic injury along with the reduction of trkB and trkC inductions.

Administration, Topical↗
PubMed1999

Role of the monocarboxylic acid transport system in the intestinal absorption of an orally active beta-lactam prodrug: carindacillin as a model.

Transport of carbenicillin (CBPC) and its orally active prodrug (carindacillin, CIPC) was studied with rat intestinal brush border membrane vesicles (BBMV). CIPC was transported uphill into BBMV in the presence of a H(+) gradient, indicating that CIPC absorption is carrier-mediated. Indeed, CIPC was predominantly transported by the monocarboxylic acid transport system, although it might be possible that CIPC possesses some affinity to the oligopeptide transporter. In contrast, CBPC exhibited no affinity to either the oligopeptide or the monocarboxylic acid transport system. Apparent uptake clearance of CIPC was approximately 70-fold greater than that of CBPC. It was clarified that the modification of the chemical structure of CBPC (a dicarboxylic acid) to CIPC (a monocarboxylic acid) by ester formation may have resulted in the increased affinity to the monocarboxylic acid transport system, which, in turn, led to improved absorption of the prodrug.

Algorithms↗
PubMed1999

NH2-terminal pentapeptide of endothelial interleukin 8 is responsible for the induction of apoptosis in leukemic cells and has an antitumor effect in vivo.

We have reported that endothelial interleukin 8 (IL-8) induces apoptosis in leukemic cells in vitro and in vivo, and that interaction between endothelial cells and leukemic cells causes induction of apoptosis through the release of endothelial IL-8 (Y. Terui et al., Biochem. Biophys. Res. Commun., 243: 407-411, 1998; Y. Terui et al., Blood, 92: 2672-2680, 1998). Here, we examined whether a pentapeptide corresponding to the NH2-terminal region of endothelial IL-8 can induce apoptosis in leukemic cells. The NH2-terminal pentapeptide Ala-Val-Leu-Pro-Arg (AVLPR) was found to significantly induce apoptosis in the leukemic cell lines K562, HL-60, Jurkat, and Daudi, as compared with the COOH-terminal pentapeptide Arg-Glu-Ala-Asn-Ser (REANS). Moreover, the NH2-terminal pentapeptide AVLPR significantly inhibited growth of i.p. and s.c. tumor masses of K562 cells and induced apoptosis in these cells in vivo. The active site of endothelial IL-8 is the NH2-terminal pentapeptide AVLPR, and this may serve as a new therapy for hematological malignancies.

Animals↗