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T Kubota

Publications and source records attributed to T Kubota.

At least 37 records · Page 2Linked to original sources

Usefulness of the prognostic score for donor safety in living donor liver transplantation.

This study sought to determine whether a prognostic score is a useful indicator of donor safety using 13 consecutive donors enrolled for liver transplantation. The donor operations were right hepatic lobectomies (n = 10) and left hepatic lobectomies (n = 3). The postoperative maximal level of serum total bilirubin was used to assess the magnitude of surgical stress. Variables such as donor age, percentage of liver resection (PLR), indocyanine green 15-minute retention rate (ICGR15), operative blood loss, operation time, prognostic score and graft weight were evaluated as predictors of the magnitude of surgical stress. The PLR and prognostic score (PS) were calculated according to the following formulae: PLR (%) = 100*Graft weight (g)/standard liver volume of the donor (mL); PS = -84.6 + 0.933*PLR (%) +1.11*ICGR15 (%) +0.999*age (years); Standard liver volume (mL) = 706.2*body surface area (m2) + 2.39. No serious complications occurred after the donor operations. Maximal bilirubin ranged from 1.9 to 10.9 mg/dL. There were no mortalities, although there were two morbidities, bile leakage and prolonged liver dysfunction. Postoperative hyperbilirubinemia was observed in two donors and in one Gilbert's syndrome donor. Linear regression analysis of each variable indicated poor correlations between those variables and maximal bilirubin. However, close correlations were seen between maximal bilirubin and both donor age and PS except for the three patients who showed postoperative hyperbilirubinemia. In these uneventful donors, statistical formulae were obtained as follows: maximal bilirubin (PMB) = 0.271 + 0.056*donor age (correlation coefficient 0.612, P < .008), PMB = 1.541 + 0.059*PS (correlation coefficient 0.597, P < .009). In conclusion, PS is useful to predict maximal bilirubin and to ensure donor safety.

Age Factors↗

Surveillance of perioperative infections after adult living donor liver transplantation.

AIM: This study was conducted to clarify the management of perioperative infectious complications after adult living donor liver transplantation (LDLT). PATIENTS AND METHODS: Fourteen adult LDLT patients were enrolled in this study. We examined the occurrence of infectious complications in these cases and the relationships of infectious complications to UNOS status and MELD score. Surveillance culture and immunoserologic analyses were performed. From the results of these analyses, we made a diagram of infection surveillance using a matrix of time and sampling site. Using the diagram, we chose sensitive antibiotics as soon as possible. RESULTS: The infection site and its pathogen were able to be detected in four (28.5%) patients, all of whom had MRSA infections, together with lung aspergillosis in one case, pseudomonas pneumonia in another, and both in another. Two patients died of lung aspergillosis. Bacteria detected in the airway tended to spread to other sites during the postoperative period. In all four patients in whom infectious diseases were detected, and in a fifth patient in whom the site of infection was not known, the UNOS status was 1. The MELD score was calculated in eight patients, six of whom had high MELD scores (>20). CONCLUSION: Most cases were manageable by choosing and changing antibiotics and antifungal drugs according to the results of surveillance cultures twice a week. However, aspergillosis had an extremely poor prognosis. Patients with a high MELD score or low UNOS status, or both, showed poor prognosis; and in them, multiple drug resistance bacteria caused severe perioperative infectious complications.

Adult↗

Anti-tumour effects of nobiletin, a citrus flavonoid, on gastric cancer include: antiproliferative effects, induction of apoptosis and cell cycle deregulation.

AIM: To demonstrate the antitumour effects of nobiletin (5,6,7,8,3',4'-hexamethoxyflavone), a citrus flavonoid extracted from Citrus depressa Hayata, on human gastric cancer cell lines TMK-1, MKN-45, MKN-74 and KATO-III. MATERIALS AND METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the TdT-mediated dUTP biotin nick-end labelling (TUNEL) method and cell-cycle analysis revealed that nobiletin acted on these cells in several ways, namely by direct cytotoxicity, induction of apoptosis and modulation of cell cycle. The efficacy of combined treatment of nobiletin with a conventional anticancer drug, CDDP, was also examined. Treatment with nobiletin 24 h prior to CDDP administration showed a synergistic effect compared to the control. CONCLUSIONS: Although the effective dose and administration route of nobiletin require further investigation, our study represents a potential successful linking of this compound with the treatment of gastric cancer.

Anticarcinogenic Agents↗

The mechanism of hypoglycemia caused by hemodialysis.

BACKGROUND: Although it is well-known that plasma glucose concentration ((G)p) decreases during hemodialysis, the precise mechanism underlying this decrease has not yet been fully elucidated. The aim of the present study was to investigate the mechanism underlying hemodialysis-induced decrease (HID) in (G)p during the dialysis in vivo or in vitro. METHODS: Using high CO2/ HCO3- dialysate, we measured (G)p by a hexose kinase method ((G)pHK) and concentrations of electrolytes, as well as pH, PCO2 and PO2 for both plasma and dialysate samples at pre- and postdialyzer sites obtained from hemodialysis patients with nondiabetic chronic renal failure (CRF). Furthermore, we studied the effect of PCO2 and acetazolamide (ACZ) on the changes in (G)pHK during the dialysis in vitro. RESULTS: After the first dialysis of CRF patients, the (G)pHK decreased from 118.3 +/- 18.0 to 98.6 +/- 5.7 mg/dl (p < 0.05), the latter value being significantly lower than glucose concentration in dialysate samples (approximately 105 mg/dl) at predialyzer sites. In the experiments of blood samples from healthy volunteers, (G)pHK decreased significantly after elevating or lowering CO2 level in the dialysates. In contrast, when the difference in PCO2 between the blood and dialysate was reduced, the HID in (G)pHK was abolished during hemodialysis. The addition of 10(-4) M ACZ to the blood samples completely prevented the development of HID in (G)pHK caused by the perfusion of high or low CO2/HCO3- dialysates. CONCLUSIONS: During hemodialysis using high CO2/HCO3- dialysate, the HID in (G)p results from the diffusion of glucose from plasma into erythrocytes, probably due to the consumption of glucose resulting from the accelerated anaerobic metabolism induced by the changes in the cytoplasmic pH of erythrocytes.

Acetazolamide↗

Energetic protons from a few-micron metallic foil evaporated by an intense laser pulse.

With detailed experimental studies and hydrodynamics and particle-in-cell simulations we investigate the role of the prepulse in laser proton acceleration. The prepulse or pedestal (amplified spontaneous emission) can completely evaporate the irradiated region of a sufficiently thin foil; therefore, the main part of the laser pulse interacts with an underdense plasma. The multiparametric particle-in-cell simulations demonstrate that the main pulse generates the quasistatic magnetic field, which in its turn produces the long-lived charge separation electrostatic field, accelerating the ions.

Journal Article↗

Dipeptidyl peptidase IV on activated T cells as a target molecule for therapy of rheumatoid arthritis.

The extracellular domain of the T cell co-stimulatory molecule CD26 possesses dipeptidyl peptidase IV (DP IV) enzyme activity. Activated T cells are known to increase expression of cell surface DP IV and some specific inhibitors of this enzyme have been reported to suppress T cell function. Previously we have identified a DP IV inhibitor, designated TMC-2, found in culture supernatant of Aspergillus oryzae. Administration of TMC-2 to rats with adjuvant arthritis caused marked suppression of paw swelling. To elucidate the mechanism of TMC-2 antiarthritic activity, we have studied its effects on T cell function. Here we show that TMC-2 inhibited DP IV activity of CD26 immunoprecipitated from T cell lysates, and also inhibited proliferative responses of T cells to specific antigen or anti-CD3 antibody. Suppression of IL-2 production was demonstrated at both the mRNA and protein levels. TMC-2 did not alter the PTPase activity of pure CD45, but when this molecule was co-precipitated from T cell lysates together with associated CD26, its PTPase was virtually completely abolished by TMC-2. These results suggest that modulation of CD45 PTPase activity might be responsible for functional suppression of T cells by TMC-2. Because the effects of TMC-2 on T cells were reversible and it was not toxic at the concentrations used, TMC-2 may be a candidate novel therapeutic agent for rheumatoid arthritis.

Arthritis, Rheumatoid↗

Frameless stereotactic radiosurgery with mobile CT, mask immobilization and micro-multileaf collimators.

We present frameless stereotactic radiosurgery using mobile CT, thermal plastic mask fixation, a vacuum-form body immobilizer and micro-multileaf collimators. A linear accelerator and a self-moving helical CT scanner gantry were installed in the same room. The isocenter of irradiation can be also aligned with the center of the CT gantry by rotating the couch. A thermal plastic mask and vacuum-form body immobilizer was used for registration and immobilization. The advantages of this system are as follows: 1) Accurate and painless frameless fractionated irradiation can be performed smoothly, as the patient's head is fixed without exchanging the couch from CT scanning to irradiation system. 2) This mask system can be applied to children, infants or adults with a previous craniotomy bone flap that must have a fixation pin placed into it. This system can be also used for fractionated radiotherapy without painful skull pin-fixed frame. 3) 1 mm micro-multileaf collimators enable irregular contour irradiation. 4) Image fusion (among CT, MRI, angiography, and PET) and 3D images can be used for irradiation planning. 5) This system can be used on any part of the body. 6) This system can be installed in any irradiation room without any extension or new construction.

Brain Neoplasms↗

Pars plana vitrectomy assisted by triamcinolone acetonide for refractory uveitis: a case series study.

AIM: To examine the outcome of a triamcinolone acetonide (TA) assisted pars plana vitrectomy (PPV) for refractory uveitis. METHODS: Six patients suffering from proliferative vitreoretinopathy (PVR) with refractory uveitis underwent a TA assisted PPV. The patients consisted of one with Vogt-Koyanagi-Harada disease, one with acute retinal necrosis, one with Behçet's disease, and three with sarcoidosis. TA was inoculated into the vitreous cavity to visualise the vitreous. In four of six patients, 4 mg of TA were intentionally left in the vitreous cavity to reduce the degree of postoperative inflammation. RESULTS: The vitreous body was clearly seen using TA during surgery, which greatly helped us to perform a posterior hyaloid resection safely and thoroughly. As we previously observed in other disease, TA allowed us to visualise the transparent vitreous and thus was helpful in removing the vitreous cortex from the retina completely in uveitis. One patient (Behçet's disease, in whom TA was intentionally left) showed an elevated intraocular pressure (IOP) transiently after surgery which was controllable by topical eye drops. The remaining TA diminished day by day and had almost completely disappeared within a month from operation. CONCLUSION: TA improved the visibility of the hyaloid and the safety of the surgical procedures and no serious complications were observed after TA assisted PPV in uveitis. Although the long term effects are still unknown, this method appears to be potentially useful as an improved treatment for PVR associated with refractory uveitis.

Adult↗

Lymphadenectomy and adjuvant therapy in endometrial carcinoma: role of adjuvant chemotherapy.

To evaluate the therapeutic benefit of lymphadenectomy and adjuvant therapy, in particular chemotherapy, we retrospectively analysed survival rates and patterns of recurrence of endometrioid adenocarcinoma in 106 patients who underwent surgery including retroperitoneal lymphadenectomy. Adjuvant chemotherapy was administered to 46 patients (42 received a platinum-based regimen) and pelvic irradiation to 12. The 5-year survival rate of 23 patients with lymph node metastasis was worse than that of patients without lymph node metastasis (60% vs 96%, P<0.0001). Recurrence was observed in 14 patients (10 patients with chemotherapy, two with irradiation, and two without adjuvant therapy); the first site of recurrence was in distant sites in 12 patients; recurrence in the pelvic sidewall or exclusively in lymph nodes was not observed. The 5-year survival rate of 18 patients with lymph node metastasis treated with chemotherapy, was 61% including all 14 with macroscopically positive nodes and all nine with paraaortic metastasis. Of seven patients with bulky positives nodes, three patients with bulky paraaortic nodes died of the disease, three of the four patients with bulky pelvic but without bulky paraaortic nodes had no recurrence. In summary, lymphadenectomy may afford a survival benefit via the debulking of macroscopically positive nodes, and the predominance of distant recurrences suggests that chemotherapy is a suitable choice as an adjuvant therapy in endometrial carcinoma after lymphadenectomy.

Adenocarcinoma↗

Cimetidine modulates the antigen presenting capacity of dendritic cells from colorectal cancer patients.

Cimetidine, a H(2) receptor antagonist, has been reported to improve survival in gastrointestinal cancer patients. These effects have largely been attributed to the enhancing effects of cimetidine on the host's antitumour cell-mediated immune response, such as inhibition of suppressor T lymphocyte activity, stimulation of natural killer cell activity and increase of interleukin-2 production from helper T lymphocytes. We conducted an in vitro study on the effects of cimetidine on differentiation and antigen presenting capacity of monocyte-derived dendritic cells from advanced colorectal cancer patients and normal controls. As a result, an investigation of expression of surface molecules associated with dendritic cells by flow cytometric analyses showed that cimetidine had no enhancing effect on differentiation of dendritic cells from cancer patients and normal controls. An investigation of [(3)H]thymidine incorporation by allogeneic mixed lymphocyte reactions revealed that cimetidine increased the antigen presenting capacity of dendritic cells from both materials. Moreover, a higher antigen presenting capacity was observed in advanced cancer patients compared to normal controls. These effects might be mediated via specific action of cimetidine and not via H(2) receptors because famotidine did not show similar effects. Our results suggest that cimetidine may enhance the host's antitumour cell-mediated immunity by improving the suppressed dendritic cells function of advanced cancer patients.

Adult↗