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T Sano

Publications and source records attributed to T Sano.

At least 163 records · Page 9Linked to original sources
PubMed2000

Dedifferentiated liposarcoma of retroperitoneum and mesentery: varied growth patterns and histological grades--a clinicopathologic study of 32 cases.

The purpose of this study was to obtain further information regarding cellular differentiation and proliferative characteristics of dedifferentiated liposarcoma (DDL) arising in the retroperitoneum and mesentery for accurate diagnosis and prognostic criteria. The patients included 20 men and 12 women, mean age, 60 years (range, 33 to 80 years). Twenty-seven tumors were located in the retroperitoneum and 5 in the mesentery. Tumor size ranged from 9 to 51 cm (mean, 24 cm). Follow-up was available on all patients and ranged from 4 to 243 months (mean, 64 months). Twenty-four (75%) patients developed local recurrences, 3 (9%) had distant metastasis, and 16 (50%) died of the disease. The predominant histology of dedifferentiation (DD) included fibrosarcoma or malignant fibrous histiocytoma (MFH) in 15 (47%), myxofibrosarcoma (myxoid MFH) in 5 (16%), mixed type in 10 (31%), and a whorling pattern in 2 (6%). Divergent differentiation, such as osseous, osteosarcomatous, chondrosarcomatous, and leiomyosarcomatous, was observed in 9 (28%). Immunoreactivity for vimentin, desmin, CD34, neurofilament, alpha-smooth muscle actin, p53, and MDM2 was observed in 32 (100%), 14 (44%), 8 (25%), 13 (41%), 14 (44%), 19 (59%), and 18 (56%) of DD areas, respectively. On the basis of a histological grading using MIB-1 (MIB-1 index range, 3% to 80%; mean, 27%) to replace mitosis counts (1 to 35/10 high-power fields [HPF]; mean, 13/10 HPF), 16 tumors each were classified as low-grade (grade 2) and high-grade (grade 3). The mixed type with poorly differentiated areas including scattered lipoblasts could be mistaken for myxoid liposarcoma but lacked the C/EBP-homologous protein-translocated in liposarcomat (CHOP-TLS) fusion genes specific for myxoid liposarcoma. Period to the first recurrence and histological grade using the MIB-1 index were associated with overall survival. Identification of DD areas, especially a poorly recognized variant of the mixed type, careful follow-up to detect early recurrence, and histological malignancy grading combined with proliferation indices are important in providing an accurate prognosis for all patients with retroperitoneal and mesenteric liposarcoma.

Adult↗
PubMed2000

Long-term magnetic resonance imaging after temporomandibular joint discectomy without replacement.

PURPOSE: The intracapsular changes in patients who underwent discectomy without disc replacement were evaluated by magnetic resonance imaging (MRI) to determine the long-term outcome of this procedure. PATIENTS AND METHODS: Thirty-three patients observed for an average of 9 years 4 months (5 to 24 years) and 10 asymptomatic volunteers underwent MRI using T1- and T2-weighted images and 3-dimensional fast imaging with a steady precession sequence (FISP-3D) technique. The intracapsular changes, especially those in the joint space, were compared with the postoperative clinical findings. RESULTS: MRI examination of the temporomandibular joint in the 33 patients (35 joints) indicated the presence of tissue with an intermediate or high signal intensity in the joint space. This tissue covered the articular surface of the condyle and fossa. Thirty-two joints had no pain or only occasional, mild pain (3 joints). No patient had severe joint pain or a low signal intensity in the joint space on MRI examination. There was no correlation between joint noise and the presence of a tissue deformity in the joint space. MRI of 2 patients with limited mouth opening showed tissue with high signal intensity in the joint space as well as an exostosis on the eminence and hypertrophy of the condyle. CONCLUSION: Long-term success is possible with discectomy without replacement. This appears to be attributable to the formation of new tissue between the condyle and fossa that acts as a pseudodisc.

Adult↗
PubMed2000

Right trisegment portal vein embolization for biliary tract carcinoma: technique and clinical utility.

BACKGROUND: Right portal vein embolization has become popular in preparation for right hepatic lobectomy. However, right trisegment portal vein embolization (R3PE) is not well established. METHODS: We performed R3PE in 15 patients with biliary tract carcinoma and 1 patient with primary sclerosing cholangitis. We used 2 types of 5.5 F triple-lumen balloon catheters to embolize portal branches of the right trisegment (the left medial, the right anterior, and the right posterior segments). RESULTS: R3PE was successful in all patients without any complications. The calculated volume of the right lobe significantly (P < .01) decreased from 650 +/- 161 cm3 before embolization to 585 +/- 143 cm3 after embolization; the volume of the left lateral segment significantly (P < .0005) increased from 240 +/- 58 cm3 to 361 +/- 66 cm3. The volume of the left medial segment was unchanged. The volume gain of the left lateral segment was larger in patients with R3PE than in those patients (n = 41) with right portal vein embolization (122 +/- 39 cm3 vs 66 +/- 35 cm3; P < .0001). Two of the 16 patients underwent only laparotomy because of peritoneal dissemination, and the remaining 14 patients underwent right hepatic trisegmentectomy with caudate lobectomy. In addition, portal vein resection was also performed in 5 patients, and pancreatoduodenectomy and right hemicolectomy was performed in 3 patients. One patient died of posthepatectomy liver failure 87 days after surgery, a mortality rate of 7.1% (1/14 patients). CONCLUSIONS: R3PE is more useful than standard right portal vein embolization in preparation for right hepatic trisegmentectomy and has the potential to increase the safety of this high-risk surgery for patients with biliary tract carcinoma.

Adult↗
PubMed2000

Fructooligosaccharide consumption enhances femoral bone volume and mineral concentrations in rats.

We examined whether the enhanced mineral absorption resulting from fructooligosaccharide (FOS) consumption affects femoral bone structure and mineral concentrations, using histomorphometrical and X-ray microanalysis. Male Wistar rats (n = 16; 42 d old) were divided into two groups, a control group (n = 8) and a FOS group (5 g/100 g FOS in the diet, n = 8). After a 3-d adaptation period, constant amounts of calcium (95 mg/d) and magnesium (8 mg/d) were fed to the rats in each group, using a pair-feeding protocol. At age 60 d, a 3-d metabolic study was initiated. Calcium and magnesium absorptions were calculated. The rats were then killed, and the right femur was embedded in polyester resin. The distal metaphysis was sagittal-sectioned, and the middle of the diaphysis and neck were cross-sectioned. Calcium, magnesium and phosphorus concentrations in the three samples were then measured. Calcium and magnesium absorptions were significantly greater in FOS-fed rats. Trabecular bone volume at the metaphysis and bone volume at the neck of the femur in FOS-fed rats were also significantly greater than those in control rats. The mineral concentration (Ca, Mg and P) in each region of the bone surface was greater in FOS-fed rats. There was a significant relationship between absorbed calcium and calcium concentrations in bone (r = 0.722, P < 0.001), and a similar relationship was found for magnesium (r = 0.720, P < 0.001). These results suggest that the enhanced calcium and magnesium absorption due to FOS consumption might enhance femoral bone volume and mineral concentrations.

Absorption↗
PubMed2000

Scanning electron microscopy subsequent to a combined treatment of NaOCl and EDTA in some non-collagenous calcified matrixes.

Using backscattered electron (BSE) imaging and scanning electron microscopy, subsequent to a combined treatment of sodium hypochlorite (NaOCl) and ethylenediamine tetra-acetic acid (EDTA) or only with EDTA etching, we observed some structures of non-collagenous calcified matrixes with the aim of revealing the correlation of deposition between calcification degree and organic amount. In human tooth enamel, the NaOCl-EDTA method eroded more intensively the hypocalcified prisms of enamel tufts containing a relatively large amount of EDTA-insoluble organic matter than the hypercalcified normal prismatic enamel containing a small amount of the organic matter. Afibrillar cementum, one of the non-collagenous calcified tissues similar to the enamel, has been reported to consist of organic-rich and poor incremental lamellae. The BSE imaging showed an alternation pattern of hypocalcification and hypercalcification. The hypocalcified lamellae were retained by EDTA etching, while the hypercalcified lamellae showed a resistance against the NaOCl-EDTA method. In the non-collagenous calcareous concretions of human pineal body, organic-rich and poor, and hyper- and hypocalcified incremental lamellae have been reported. The deposition pattern of calcification degree and organic amount was similar to that in afibrillar cementum, and the hypercalcified lamellae showed a resistance against the NaOCl-EDTA method. In conclusion, the high and the lower calcified regions of non-collagenous calcified matrixes contained smaller and larger amounts of EDTA-insoluble organic matter respectively. Moreover, scanning electron microscopy subsequent to the NaOCl-EDTA method corresponding to the BSE imaging clearly showed fine calcified structures compared with the BSE imaging.

Calcification, Physiologic↗
PubMed2000

Blunting of pulmonary but not systemic vasodilator responses to dobutamine in newborn lambs.

Little is known about the changes in systemic and pulmonary vascular responses to dobutamine that occur during postnatal development. To address this question, vascular pressures and cardiac output were measured in anesthetized 1- to 2-d-old (n = 6), 7- to 10-d-old (n = 7), and 6- to 8-wk-old lambs (n = 6) while dobutamine was infused incrementally in the dose range of 0.5-40 microg x kg(-1) x min(-1). Dobutamine reduced pulmonary vascular resistance in the three age groups (all p<0.005). However, although this reduction reached a plateau over the infusion range of 15-40 microg x kg(-1) x min(-1) at all ages, its magnitude was less (p<0.02) in 1- to 2-d-old lambs (24+/-2%) than in 7- to 10-d-old (41+/-7%) or 6- to 8-wk-old lambs (42+/-6%). Over the same infusion range, dobutamine produced a fall in systemic vascular resistance (all p<0.005) that was proportionally similar in 1- to 2-d-old (51+/-3%), 7- to 10-d-old (48+/-3%), and 6- to 8-wk-old lambs (42+/-6%). In separate subgroups of 1- to 2-d-old lambs, pulmonary and systemic responses to dobutamine were not affected by pretreatment with selective alpha1-, beta1-, or beta2-adrenoceptor antagonists. Taken together, these findings suggest that the pulmonary but not systemic vasodilator response to dobutamine in lambs is blunted in the initial days after birth, and that this pulmonary effect is not directly related to the adrenoceptor-stimulating properties of dobutamine.

Adrenergic Antagonists↗
PubMed2000

Expression of corticotropin-releasing hormone messenger ribonucleic acid in human pituitary corticotroph adenomas associated with proliferative potential.

Among the factors that promote the growth of human pituitary corticotroph adenomas (hPCAs), the proliferative potential of CRH secreted by hPCAs on these tumors is not well known. In this study, the CRH messenger ribonucleic acid (mRNA) transcripts were demonstrated on paraffin sections using the quantitative in situ hybridization method in 37 of 43 hPCAs, including 17 of 22 microadenomas, 15 of 15 macroadenomas, and 5 of 6 locally invasive adenomas according to Hardy's classification of pituitary adenomas. The more important findings were that CRH mRNA signal intensity in pituitary corticotroph adenoma cells was linearly correlated with Ki-67 tumor growth fractions (r = 0.802; P < 0.0001), and in macroadenoma and locally invasive adenoma cells it was significantly higher than in microadenoma cells (P = 0.035). On the other hand, CRH mRNA transcript accumulation was absent or negligible in 10 normal pituitary glands (P = 0.005). This is the first report of the frequent expression of CRH mRNA localized in human pituitary corticotroph adenoma cells. These results indicate that CRH from a local source of corticotroph adenoma cells not only has autocrine/paracrine functions in corticotroph adenomatous tissue, but also is an important factor associated with a proliferative potential of hPCAs.

Adenoma↗
PubMed2000

Fucoidan is the active component of fucus vesiculosus that promotes contraction of fibroblast-populated collagen gels.

The fibroblast-populated collagen gel culture method has been evaluated as a dermal model of wound contraction and granulation in tissues during the wound healing process and as an in vitro model of dermal tissue. We previously reported that an extract of Fucus vesiculosus promoted fibroblast-populated collagen gel contraction and that the promotion of the gel contraction was due to the increased expression of integrin alpha2beta1 on the surface of the fibroblasts. In this study, we investigated the active component of the extract of this alga using extraction and fractionation techniques. Water extraction of the alga was followed by precipitation with excess ethanol and then gel filtration with the boundary molecular weight of 30,000. The high molecular weight fraction obtained from gel filtration was fractionated by ion exchange chromatography on diethylaminoethyl cellulose column to give active fractions that have more polar properties. These polar, high molecular weight fractions which contained molecules with fucose and sulfate groups showed significant gel contraction-promoting activity and integrin expression-enhancing activity, and were estimated to be the sulfated-polysaccharide fucoidan. Commercially available fucoidan showed similar activities to the above-described fraction of this alga. Although it remains necessary to precisely identify the specific active component, the above results indicate that fucoidan is the active component which promotes collagen gel contraction, and also indicate the possibility that it dose so by enhancing the integrin alpha2beta1 expression.

Anticoagulants↗
PubMed2000

Synthesis of methoxy-2-quinolones via pummerer-type cyclization of N-aryl-N-methyl-3-(phenylsulfinyl)propionamides.

The thionium ions 10 generated by Pummerer reaction of N-aryl-N-methyl-3-(phenylsulfinyl)propionamides 4 caused not only an electrophilic cyclization reaction producing 2-quinolones 8, but also the formation of the vinyl sulfides 5 and 6 in favor of the latter reaction. On the other hand, the treatment of the vinyl sulfides 5 and 6 with p-toluenesulfonic acid induced cyclization to afford the 2-quinolones 8 in excellent to moderate yields, depending on the electronic properties of the aromatic ring, thus providing a convenient method for the synthesis of methoxy-2-quinolones.

Acetic Anhydrides↗
PubMed2000

A chiral synthesis of four stereoisomers of 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, an inducer of Parkinson-like syndrome.

Four stereoisomers of 1,3-dimethyl-1,2,3,4-tetrahydroisoquinoline, an inducer of Parkinson-like syndrome, were synthesized by applying a new method of 1,2,3,4-tetrahydroisoquinoline (TIQ) synthesis utilizing the Pummerer reaction as a key step. The chiral centers at C-1 and C-3 were constructed by two routes starting from alaninol (3) and 1-phenylethylamine (4) as a chiral source. Enantiomerically pure 1,3-dimethyl-TIQs (1R,3S)-(2) [corrected], (1S,3R)-(ent-2) [corrected], (1S,3S)-(1) [corrected], and (1R,3R)-(ent-1) [corrected] were prepared in a stereochemically unambiguous manner from 3 in 11 steps (route I) and from 4 in 6 steps (route II). The conformations of tetrahydroisoquinoline ring in 1-methyl, 3-methyl, and 1,3-dimethyl-TIQs were discussed on the basis of their CD, 1H-NMR spectra, and steric energies.

Chromatography, High Pressure Liquid↗
PubMed2000

Effects of intravenous theophylline, aminophylline and ethylenediamine on antigen-induced bronchoconstriction in guinea pigs.

The antiasthmatic effect of i.v. injection of theophylline was compared with that of aminophylline by using an antigen-induced bronchoconstriction model in sensitized guinea pigs. Both theophylline and aminophylline showed dose-dependent inhibition of antigen-induced bronchoconstriction. Statistically significant differences were observed at theophylline doses of 20 and 40 mg/kg and at aminophylline doses of 25 and 50 mg/kg. Thus, antiasthmatic effects of both drugs appeared to be similar. In addition, intravenous ethylenediamine did not influence either airflow in normal guinea pigs or bronchoconstriction induced by antigen at doses up to 30 mg/kg. In conclusion, the ethylenediamine in aminophylline may not influence the antiasthmatic action of theophylline, and the therapeutic effects of theophylline and aminophylline are suggested to be similar.

Aminophylline↗
PubMed2000

Method for linking a synthesized protein to its mRNA-DNA complex.

A nascent protein remains in a complex with its ribosome and mRNA if the stop codon is deleted from the mRNA. In the same manner, mRNA forms a stable complex with DNA if the transcription termination is blocked. In principle, if both mRNA translation and DNA transcription termination are prevented, the protein should stay in a complex with its mRNA and DNA. A method is designed to test these possibilities. Using an immobilized luciferase gene sequence, a functional luciferase protein is produced that remains associated through its mRNA with its DNA, confirming the feasibility of the proposed scheme. It has potential application for in vitro synthesis of proteins and protein micro-arrays.

DNA↗
PubMed2000

Mucosal change of the stomach with low-grade mucosa-associated lymphoid tissue lymphoma after eradication of Helicobacter pylori: follow-up study of 48 cases.

Low-grade mucosa-associated lymphoid tissue (MALT) lymphoma of the stomach has been demonstrated to be closely linked to Helicobacter pylori (H. pylori) and to be frequently remissioned after the cure of H. pylori infection. Several previous studies have focused on proliferating lymphocytes but little is known about gastric epithelial change and the duration of the remission after the cure of H. pylori infection. We performed a long-term follow-up investigation on the effects of anti-H. pylori treatment on MALT lymphoma and chronic gastritis at the histologic and molecular levels. Forty-eight patients with low-grade gastric MALT lymphoma and 28 chronic gastritis patients in whom H. pylori infection was eradicated were studied. After eradication, 43 MALT lymphoma patients showed complete histologic remission and continuous remission was observed during follow-up for up to 43 months (mean, 17.8 months). As for epithelial changes after eradication, "emptiness of lamina propria" was more pronounced in the mucosa with MALT lymphoma than that with chronic gastritis, and its severity in MALT lymphoma cases significantly decreased during the observation period whereas the glandular area increased. Cystic change of the fundic gland also occurred more frequently in MALT lymphoma cases than chronic gastritis cases. B-cell clonality before eradication analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) was detected in almost all MALT lymphoma cases (43 cases), but rare in chronic gastritis cases (6 cases). After eradication, in spite of histologic regression, 21 MALT lymphoma patients had a persistent monoclonal population during the follow-up period. B-cell monoclonality preceding the malignant transformation was noted in 4 cases. These observations indicate that 1) complete histologic remission of low-grade gastric MALT lymphomas seems stable even if a monoclonal B cell population is detectable in some cases, 2) there may be a stage of disease where monoclonal B cells are present but there is no histologic evidence of MALT lymphoma, and 3) regenerative change of the damaged glands may occur in histologic regressed MALT lymphoma cases.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2000

Highly efficient kinetic resolution of beta-halohydrins catalyzed by a chiral 1,2-diamine.

Kinetic resolution of racemic beta-halohydrins has been achieved by reaction with benzoyl chloride in the presence of a catalytic amount (0.3 mol%) of a chiral diamine combined with diisopropylethylamine to afford the corresponding benzoates and unreacted beta-halohydrins in good to excellent enantioselectivities. The benzoate can be converted to the corresponding allylic benzoate without loss of optical purity by treatment with (1,5-diazabicyclo[4.3.0]non-5-ene).

Acylation↗
PubMed2000

Relationship between vanadate induced relaxation and vanadium content in guinea pig taenia coli.

Abstract: Vanadate has been known to induce a transient increase in high K+ induced contraction, and also gradually relax the high K+ contraction itself in guinea pig taenia coli. The relationship between the rate of relaxation and ion content of Na+, K+, and V ion at the cellular level was investigated when vanadate was applied to contracted muscle. Tissue Na+ and V ion content increased linearly, depending on the time after vanadate treatment, reaching maximum levels of approximately 50 mM x kg(-1) and 0.25 mM x kg(-1) wet weight, respectively. There was a positive correlation between the V ion and Na+ contents, while there was a negative correlation between both ions and the relaxed rate of the high K+ induced contraction. The uptake of V ion was affected by the external K+ concentration, and the maximum rate of V ion uptake decreased to 40% in the presence of 90 mM external K+. These results suggest that a small amount of V ion was enough to inhibit the Na+ pump activity and muscle contraction in the high K+ solution.

Animals↗
PubMed2000

[Extended liver resection for hilar cholangiocarcinoma].

Liver resection for hilar cholangiocarcinoma should be designed for individual patients, based on both precise diagnosis of cancer extent and accurate evaluation of hepatic functional reserve. Therefore we have developed various types of hepatic segmentectomy. Combined caudate lobectomy is essential in every patient with separated hepatic confluence. So-called extensive hepatectomy, resection of 50% or more of the hepatic mass, includes right lobectomy and right or left trisegmentectomy. Right lobectomy with caudate lobectomy is indicated when the progression of cancer is predominant in the right anterior and posterior segmental bile ducts. The plane of liver transection is along the Cantlie line, and the left hepatic duct is divided just at the right side of the umbilical portion of the left portal vein. Right trisegmentectomy with caudate lobectomy is performed in carcinoma which involves the right hepatic ducts in continuity with the left medial segmental bile duct. The umbilical portion of the left portal vein is freed from the umbilical plate by dividing the small portal branches arising from the cranial side of the umbilical portion. Then the left lateral segmental bile ducts are exposed and divided at the left side of the umbilical portion of the left portal vein. Left trisegmentectomy with caudate lobectomy is suitable for carcinoma which involves the left intrahepatic bile duct in continuity with the right anterior segmental bile duct. Liver transection is advanced along the right portal fissure. The right posterior segmental bile duct is usually divided distal to the confluence of the inferior and superior branches.

Bile Duct Neoplasms↗