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T Nishi

Publications and source records attributed to T Nishi.

At least 73 records · Page 4Linked to original sources
PubMed2000

Intestinal fat suppresses protein-induced exocrine pancreatic secretion in chronically bile-pancreatic juice-diverted rats.

Previously, we showed that the increase in pancreatic enzyme secretion was lower after feeding a casein diet containing fat than that after feeding a fat-free casein diet in chronically bile-pancreatic juice (BPJ)-diverted rats. In the present study, we determined whether the suppressive effects of fats on flow volume of BPJ and pancreatic enzyme secretion depend on delaying gastric emptying and examined the characteristics of the suppression with intraduodenal instillation of soybean oil or lecithin in BPJ-diverted rats. The study was conducted as three separate experiments using conscious rats with chronic BPJ diversion by means of a common bile-pancreatic duct catheter. The flow volume of BPJ and the secretion of pancreatic amylase and trypsin were determined after intraduodenal instillation of the test solution. Exocrine pancreatic secretion was strongly stimulated by administration of guanidinated casein hydrolysate (HGC, 150 mg/ml) in chronic BPJ-diverted rats. However, pancreatic secretion after administration of an emulsion containing HGC with either soybean oil (100 mg/ml) or mixed fat (50 mg/ml soybean oil + 50 mg/ml lecithin) was much lower than that after administration of HGC alone. In contrast, administration of the soybean oil emulsion without HGC resulted in a small, but significant increase in the volume of BPJ. The suppressive effects of soybean oil (100 mg/ml) on the increases in the BPJ flow and enzyme secretion were similar to those of sodium taurocholate (10 mg/ml), and there was no additive effect of soybean oil on taurocholate suppression. In conclusion, duodenally instilled soybean oil suppressed increases in flow volume of BPJ and pancreatic enzyme secretion induced by HGC in chronic BPJ-diverted rats, showing that the suppressive effect of the fat does not depend on delaying gastric emptying.

Animals↗
PubMed2000

Early prediction of long-term survival and the timing of liver transplantation after the Kasai operation.

BACKGROUND/PURPOSE: The aim of this study was to determine early prognostic indicators for the prediction of long-term survival rate and timing of the liver transplantation after the Kasai operation. METHODS: A retrospective chart study was performed on 142 patients with biliary atresia (BA). The patients were divided in a success and a failure group, according to whether the patients serum bilirubin levels returned to normal (less than 1.0 mg/dL) within 3 months. The differences in survival rates and performance status between the 2 groups were analyzed statistically. RESULTS: The difference in cumulative survival rate between the 2 groups was striking. When the current status of the 40 patients who had survived for over 12 years was compared, 16 patients (53.3%) from the success group and 1 (9.1%) from the failure group had normal bilirubin levels, normal growth, no esophageal varix, and no hypersplenism. From the Kaplan-Meier survival curve, 3 types of deterioration were identified. Type 1 was death within 3 years. In type 2, deterioration occurred from 4 to 13 years. Type 3 was defined as unexpected deterioration in the success group, and its incidence was extremely low. CONCLUSIONS: Serum bilirubin level at 3 months after the Kasai operation can be used to predict long-term survival and the time when the onset of liver failure is likely to occur.

Biliary Atresia↗
PubMed2000

Umbilical cord ulcer: a serious in utero complication of intestinal atresia.

We have experienced six cases of umbilical cord ulcer that resulted in life-threatening antenatal fetal haemorrhage. Fetal distress and bloody amniotic fluid that led to intrauterine and neonatal death in four patients complicated the pregnancy courses. The remaining two infants are still alive. All the infants had upper intestinal atresia below the papilla of Vater. Pathologically, umbilical arteries and surrounding Wharton's jelly were necrotic in all cases. Activated macrophages containing pigment granules were present within the ulcer bed, necrotic areas of Wharton's jelly and fetal membranes. During the same period, we encountered 38 other cases of upper intestinal atresia and the placentae were examined in 23 cases. Microscopic degeneration of Wharton's jelly was seen in three out of 23 cases. Total bile acids content in amniotic fluid was elevated in one case of umbilical cord ulcer. We speculate that the umbilical cord ulcer is closely related to in utero regurgitation of the bile. We also think that the incidence of this serious association is higher than has been reported previously.

Adult↗
PubMed2000

Clinicopathological studies of esophageal carcinosarcoma: analyses of its morphological characteristics using endoscopic, histological, and immunohistochemical procedures.

BACKGROUND AND STUDY AIMS: Carcinosarcoma of the esophagus is a rare malignant neoplasm consisting of both carcinomatous and sarcomatous components, which characteristically forms polypoid tumors. PATIENTS AND METHODS: Seven carcinosarcomas were analyzed using endoscopic, histological, and immunohistochemical procedures. Endoscopically, six of the seven lesions were found to be of the protruding type, while the other one was an ulcerating tumor. RESULTS: In all seven cases, the carcinomatous component consisted of differentiated squamous cell carcinoma, and the sarcomatous component was spindle cell carcinoma. Histological analyses demonstrated that the majority of the protruding tumors consisted of the sarcomatous component, while the ulcerating tumor mainly consisted of squamous cell carcinoma. The Ki-67 (MIB-1) labeling index (LI) of the carcinomatous component (28.2%) did not differ significantly from that of the sarcomatous component (25.5%). The sarcomatous component showed abundant expression of type IV collagen and laminin. CONCLUSIONS: It is conceivable that the carcinomatous and sarcomatous components grow separately from the early stage of the tumors, and that the sarcomatous component forms a protruding tumor mass because it has abundant stroma positive for type IV collagen and laminin.

Aged↗
PubMed2000

Clinicopathologic study of mass-screened neuroblastoma with special emphasis on untreated observed cases: a possible histologic clue to tumor regression.

Spontaneous regression and maturation of neuroblastoma (NB) are well documented and occur frequently in infants, including those detected by mass screening. To seek histologic clues for regression/maturation in mass-screened NB, clinicopathologic features of 12 tumors that were resected after 2 to 18 months of untreated observation were reviewed. Unobserved screened and age-matched unscreened patients were also studied. To evaluate the possible important role of apoptosis, apoptotic cells were detected by in situ deoxyribonucleic acid (DNA) nick end labeling and immunohistochemical stain for activated caspase-3. Nests with a varying degree of reduced cellularity ("less cellular" and "hypocellular" nests) were common in patients younger than 18 months of age, and were rare in older patients. Two characteristic cells, which have not been focused previously, were frequent, especially in the hypocellular nests. One showed amorphic eosinophilic cytoplasm with pyknotic nuclei and the other contained plump cytoplasm with well-maintained nuclei. These cells were also observed in 89% of the unobserved screened NBs and 79% of the age-matched unscreened patients with good outcome, whereas they could not be confirmed in any of the age-matched unscreened NBs with poor outcome. The amorphic and plump cells were negative for activated caspase-3 and in situ DNA nick end labeling. From these results, the authors hypothesize that these cells most likely represent a degenerative process, in either a state before the activation of caspase-3 or a caspase-independent form of cell death. The presence of less cellular and hypocellular nests with amorphic/plump cells may serve as one of the important clues in predicting tumor prognosis.

Age Factors↗
PubMed2000

Natural course of neuroblastoma detected by mass screening: s 5-year prospective study at a single institution.

PURPOSE: To describe various favorable courses of neuroblastoma (NBL) detected by mass screening and to present our observation program as a temporary treatment option, to be used until a final decision is made regarding the mass screening program for 6-month-old infants. PATIENTS AND METHODS: Between October 1993 and November 1999, 26 of 51 patients with NBL detected by mass screening were enrolled in our observation program. The criteria for observation included urinary vanillylmandelic acid (VMA) and homovanillic acid (HVA) levels less than 50 microg/mg creatinine, smaller tumor size (< 5.0 cm), preoperative status, and granted informed consent. Patients were divided into four groups according to changes in urinary VMA and HVA values and tumor size. Patients who no longer fulfilled criteria underwent surgery. RESULTS: The observation period ranged from 4 to 73 months. Urinary VMA and HVA levels decreased in 19 of 26 patients, often by age 16 months. Eighteen patients had regressing tumors, and in 10 of these cases, the tumor was undetectable or barely detectable by imaging techniques. Four patients younger than 12 months had increased tumor marker levels and tumor volume, histologically reflecting neuroblastic proliferation. The remaining three patients, all older than 18 months, had varied tumor marker levels but increased tumor volume, histologically reflecting an increase in Schwann cells. No upgrading of tumor stage or unfavorable biologic factor was noted in any patient. CONCLUSION: None of our patients showed evidence of transition from favorable to unfavorable prognosis, a finding that points to a reduction in the significance of screening as a public health measure. Until results of ongoing screening trials involving older patients have been evaluated, the observation program can be used as a temporary measure to avoid, with little risk, unnecessary surgical intervention.

Abdominal Neoplasms↗
PubMed2000

[Research and development of cilostazol: an antiplatelet agent].

In our study, we focused on the fact that platelets play a significant role in thrombus formation in the arterial vessels, and started exploratory research on the antiplatelet agent with a vasodilating action in order to discover a more effective drug for arterial thrombosis. We synthesized many 2(1H)-quinolinone derivatives and evaluated their inhibition of platelet aggregation and their vasodilating activities. First we found cilostamide, which has an amide moiety in the side chain. This compound possessed desired activities, but it caused a side effect of tachycardia, and so, unfortunately, we were unable to pursue its development. After many efforts to modify the side chain moiety to eliminate this side effect, we finally invented cilostazol (OPC-13013), a 2(1H)-quinolinone derivative with a tetrazol ring in the side chain. Cilostazol inhibited human platelet aggregation induced by various stimuli including shear stress in vitro and showed potent antiplatelet effects both in vitro and ex vivo. It was also shown that the drug has antithrombotic effects in experimental thrombus models and a vasodilating activity of the femoral artery and vertebral artery. The mechanism of the action for cilostazol is specific inhibition of cyclic nucleotide phosphodiesterase type 3 (PDE3). Cilostazol was marketed first in Japan in 1988 and later in seven other countries for the treatment of chronic arterial occlusion. It was launched in the U.S. in 1999, and approved in United Kingdom for the treatment of intermittent claudication. More recently, cilostazol was shown to be effective in a clinical prevention study on recurrence of cerebral infarction, and has been applied to the approval of the indication in Japan.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed2000

Production of betacyanins by a cell suspension culture of table beet (Beta vulgaris L.).

A cell suspension culture of table beet (Beta vulgaris L.) was established for efficient betacyanin production from violet callus induced from the hypocotyls of aseptic seedlings. This suspension culture produced large amounts of betacyanins. The betacyanin content increased with increasing cell growth during the log phase. Reducing the total nitrogen concentration (30 mM) and modifying the ratio of ammonium to nitrate (1:14) resulted in an increased betacyanin content. Supplementation of Fe2+ to the LS medium also promoted betacyanin production. The maximal betacyanin yield was achieved with a 2 mM Fe2+ concentration. Combining these conditions, we established a revised LS medium to improve betacyanin productivity (250 mg/l for a 14-day culture).

Carbocyanines↗
PubMed2000

Sigmoid sinus thrombosis after mild closed head injury in an infant: diagnosis by magnetic resonance imaging in the acute phase--case report.

Intracranial sinus thrombosis following a mild closed head injury without a skull fracture or intracranial hematoma is extremely rare. A 23-month-old girl presented with vomiting and gait ataxia 1 day after occipital trauma. Computed tomography revealed a slightly increased density area in the region of the left sigmoid sinus. T1-weighted magnetic resonance (MR) imaging demonstrated an isointense area in the left sigmoid sinus and T2-weighted imaging showed a hyperintense area reflecting the characteristics of oxyhemoglobin. MR angiography and cerebral angiography indicated occlusion of the left sigmoid sinus. After 4 days of conservative treatment, her symptoms subsided completely. Follow-up MR angiography and cerebral angiography showed recanalization of the sigmoid sinus. The MR images and MR angiograms were useful for both early diagnosis and follow-up. Treatment should reflect the severity of individual cases, and early diagnosis will help achieve a good outcome.

Acute Disease↗
PubMed2000

Suppression of the tissue factor-dependent coagulation cascade: a contributing factor for the development of intratumoral hemorrhage in glioblastoma.

To clarify factors that may contribute to the development of intratumoral hemorrhage, we analyzed the expression of tissue factor (TF), an initiator of the extrinsic coagulation pathway, and of tissue factor pathway inhibitor (TFPI) in glioblastomas with or without massive intratumoral hematoma. Among 196 glioma cases reviewed, there were 13 with macroscopic intratumoral hemorrhage. We focused on the glioblastomas and used immunoblot- and immunohistochemical methods to compare the expression of TF and TFPI in 9 glioblastomas with macroscopic hematoma and 30 glioblastomas without macroscopic hemorrhage. Although TF was expressed in most glioblastomas irrespective of the presence or absence of macroscopic hemorrhage, the staining patterns differed significantly: TF-positive glioma cells were diffusely present in the non-hemorrhage group; in the group with hemorrhage, positive cells, primarily macrophages, were scattered throughout the tissue examined. The expression of TFPI was significantly higher in the group with than in the group without hemorrhage. Our results suggest that local suppression of the TF-dependent coagulation cascade is a contributing factor that permits the occurrence of intratumoral hemorrhage.

Adult↗
PubMed2000

Gene delivery with optimized electroporation parameters shows potential for treatment of gliomas.

Electroporation, a standard laboratory method of introducing exogenous molecules into cells, has been gaining importance as a very effective non-viral physical technique of gene delivery. In this study, we have used subcutaneous model of the C6 rat glioma cells and established an optimal condition to obtain very high gene expression in tumor tissues using both reporter and functional genes. Tumors grown on the flanks of Wistar rats are exposed and directly injected with plasmid DNA having the constructs of luciferase, green fluorescent protein and, the fragment of the diphtheria toxin, DT-A. The tumors are then subjected to square wave pulses from an electroporator. Gene expression is found to be several orders of magnitude higher when the tumors are pulsed with the optimized electrical parameters compared to the controls. For luciferase, the enhancement is approximately 135-fold, for the green fluorescent protein, gene expression is seen over a wide area within the sections examined, as contrast to a few punctate dots in the control specimens, and finally, DT-A shows massive death in the tumor tissue. A special circular array of six needles through which pulses are delivered with rotating electric field is found to be highly efficient in transferring genes inside the tumor. Direct injection of plasmid DNA followed by electroporation allows very high in vivo gene transfer and its subsequent expression into tumor tissues. This method may be applicable to any solid tumor.

Animals↗
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

Frequent expression of sialyl Le(a) in human esophageal squamous cell carcinoma.

Sialyl Le(a) antigen (CA19-9), a member of a family of high molecular weight glycoproteins, was originally described as a gastrointestinal- and pancreatic-specific tumor marker. Recent studies have demonstrated that sialyl Le(a) is a ligand for E-selectin and may play an important role in tumor metastasis. However, expression patterns of sialyl Le(a) have not yet been established in human esophageal carcinomas. In this study, we examined sialyl Le(a) expression and its histopathological localization in human esophageal squamous cell carcinoma. Sialyl Le(a) immunoreactivity was detected in 28 (51.9%) of the 54 esophageal squamous cell carcinomas, regardless of the depth of tumor invasion, vascular invasion or lymph nodal status. In 13 cases (29.5%), significant sialyl Le(a) expression was detected not only in the intramucosal carcinoma components, but also in the invasive carcinoma components. These observation suggested that sialyl Le(a) expression is associated with early-stage cancer progression.

CA-19-9 Antigen↗
PubMed2000

[Schwannoma].

Explore the source record for details and available documents.

Brain Neoplasms↗
PubMed1999

Apple-peel intestinal atresia associated with balanced reciprocal translocation t(2;3)(q31.3;p24.2) mat.

Apple peel intestinal atresia is an apple-peel-appearing bowel obstruction of unknown cause. We describe a Japanese girl with the apple-peel jejunal atresia associated with apparently balanced reciprocal translocation between chromosomes 2 and 3, t(2;3)(q31. 3;p24.2)mat. The translocation breakpoints in the patient may become candidate regions for the putative gene causing apple-peel atresia. Alternatively, the association of the two abnormalities in the patient is coincidental because her phenotypically normal mother had the same chromosome translocation.

Chromosome Banding↗
PubMed1999

Tissue factor expressed in pituitary adenoma cells contributes to the development of vascular events in pituitary adenomas.

BACKGROUND: Tissue factor (TF) was initially identified as an important factor in the initiation of coagulation. TF has recently been found to be expressed highly in certain types of malignant tumors. It has also been reported to be involved in systemic coagulopathy in cancer patients and in the proliferative and invasive activities of tumor cells. Tissue factor pathway inhibitor (TFPI) is a strong biologic inhibitor of TF. To the authors' knowledge, this is the first study of the expression of TF and TFPI in human pituitary adenoma. METHODS: The expression of TF and TFPI were analyzed by immunohistochemical methods in human pituitary adenoma samples. To examine whether TF and TFPI expression influence the proliferative and/or invasive character of pituitary adenomas, the authors determined the MIB-1 labeling indices and invasiveness of all the pituitary adenomas they examined. Furthermore, to determine whether TF contributes to coagulation inside adenoma tissues, the incidence of cysts or hematomas in adenomas was analyzed. RESULTS: In cells from 29 of 83 pituitary adenomas, overexpression of TF was observed. This was not the case for normal pituitary gland cells. TFPI was not expressed in either the adenomas or the normal pituitary glands from adenoma-bearing individuals. The expression of TF was significantly correlated with the formation of cysts or hematomas in pituitary adenomas. However, no such correlation with either the proliferative activity or the invasive character of the adenomas was observed. CONCLUSIONS: Locally overexpressed TF in adenoma cells may contribute to the development of vascular events, such as infarction and/or hemorrhagic infarction, in pituitary adenomas.

Adenoma↗
PubMed1999

A novel human CC chemokine, eotaxin-3, which is expressed in IL-4-stimulated vascular endothelial cells, exhibits potent activity toward eosinophils.

IL-4 has been shown to be involved in the accumulation of leukocytes, especially eosinophils, at sites of inflammation by acting on vascular endothelial cells. To identify novel molecules involved in the IL-4-dependent eosinophil extravasation, cDNA prepared from HUVEC stimulated with IL-4 was subjected to differential display analysis, which revealed a novel CC chemokine designated as eotaxin-3. The human eotaxin-3 gene has been localized to chromosome 7q11.2, unlike most other CC chemokine genes. The predicted mature protein of 71 aa showed 27-42% identity to other human CC chemokines. The recombinant protein induced a transient increase in the cytosolic Ca2+ concentration and in vitro chemotaxis on eosinophils. Furthermore, in cynomolgus monkeys, the accumulation of eosinophils was observed at the sites where the protein was injected. Eotaxin-3 inhibited the binding of 125I-eotaxin, but not 125I-macrophage inflammatory protein-1alpha, to eosinophils and acted on cell lines transfected with CCR-3, suggesting that eotaxin-3 recognized CCR-3. IL-13 as well as IL-4 up-regulated eotaxin-3 mRNA in HUVEC, whereas neither TNF-alpha, IL-1beta, IFN-gamma, nor TNF-alpha plus IFN-gamma did. The expression profile of eotaxin-3 is different from those of eotaxin, RANTES, and monocyte chemoattractant protein-4, which are potent eosinophil-selective chemoattractants and are induced by either TNF-alpha or TNF-alpha plus IFN-gamma. These results suggest that eotaxin-3 may contribute to the eosinophil accumulation in atopic diseases.

Amino Acid Sequence↗