Search PubMed⌕ Search

Biomedical subjects

T Tani

Publications and source records attributed to T Tani.

At least 55 records · Page 3Linked to original sources
PubMed2001

Effects of zinc deficiency and corticosterone elevation on bone marrow in rats.

OBJECTIVE: The effects of zinc deficiency and serum corticosterone elevation, in a zinc-deficient state, on rat bone marrow were studied. MATERIALS AND METHODS: Male Sprague-Dawley rats were divided into the following four groups: zinc-adequate (ZA), restricted ZA (RZA), zinc-deficient (ZD) and ZD with the injection of Mifepristone (ZD+Mife). Platelet and reticulocyte counts, levels of serum zinc and corticosterone, bone marrow cellularity and morphological alterations of marrow were examined in all rats. RESULTS: Decreased marrow cellularity, decreased numbers of peripheral platelets and reticulocytes, and increased adipocytes in the marrow were observed in ZD rats. The injection of Mifepristone improved marrow cellularity, and increased the number of platelets, while decreasing adipocytes in the marrow in ZD rats. CONCLUSION: Both zinc deficiency itself and the associated serum corticosterone elevation induced bone marrow suppression in rats.

Adipocytes↗
PubMed2001

Clonal analysis of esophageal squamous cell carcinoma with intraepithelial components.

OBJECTIVE: In tumors of the upper aerodigestive tract, field carcinogenesis is a prevailing concept which suggests that such tumors are commonly of multiclonal origin. METHODS: To test this possibility, we applied a PCR-based clonality assay utilizing the polymorphic locus of the human androgen receptor gene (HUMARA) in female patients with esophageal squamous cell carcinomas (SCCs). DNA was extracted from small pieces of tissues microdissected from multiple points of intraepithelial and invasive parts of each tumor and the adjacent epithelia in 12 cases. The HUMARA locus was PCR amplified with or without prior digestion with Hpa II. PCR products were analyzed by a genetic analyzer and polyacrylamide gel electrophoresis followed by silver staining. RESULTS: In each of 8 informative cases, the pattern of X chromosome inactivation of the major cell population in each sample was common among the samples from the invasive part and among those samples, if any, from the intraepithelial part, and was concordant between the intraepithelial and invasive parts in 5 cases and discordant in 1 case. Out of the samples of adjacent epithelia, a monoclonal pattern was demonstrated in 8 basal cell hyperplasias and 3 dysplasias, of which 2 and 1, respectively, showed inactivation patterns discordant with those of the concomitant cancers. CONCLUSION: Esophageal SCCs may often be preceded or accompanied by multiclonal precancerous lesions, and may develop through the outgrowth of single or less commonly multiple dominant clones.

Aged↗
PubMed2001

Cellular membranes that undergo cyclic changes in tension: Direct measurement of force generation by an in vitro contractile vacuole of Paramecium multimicronucleatum.

The contractile vacuole of the fresh water protozoan Paramecium is a membrane-bound vesicle that expels excess cytosolic water, acquired osmotically, through its periodic exocytotic activity. The in vitro contractile vacuole, isolated in a small amount of cytosol from the Paramecium cell and confined under mineral oil, showed periodic rounding and slackening at regular intervals for an extended time. The contractile vacuole rounded against the cytosol-mineral oil boundary tension. The tension at the surface of the contractile vacuole is, therefore, assumed to increase during the rounding phase. We first estimated the tension relative to the boundary tension from the degree of compression of the contractile vacuole by the boundary. We then determined the absolute value for the tension at the surface of the contractile vacuole from the degree of bending of an elastic carbon fiber microcantilever (8 microm thick; 2 mm long), whose free end was placed at the surface of an in vitro contractile vacuole. The tension was found to increase to its maximum value of approximately 5 mN m(-)(1) when the contractile vacuole rounded. This value was more than 35 times higher than that for the slackened contractile vacuole. Electron micrographs of conventional thin sections of chemically fixed in vitro contractile vacuoles as well as those of in vivo contractile vacuoles obtained from rapid frozen and cryosubstituted cells revealed the lack of any ultrastructural evidence for the presence of a fibrous network system surrounding the contractile vacuole. Thus we conclude that the mechanism(s) by which tension is developed at the surface of the contractile vacuole membrane resides in the contractile vacuole membrane itself. We propose a hypothesis that periodic changes in the spontaneous curvature of the contractile vacuole's lipid bilayer membrane is involved in the periodic development of higher contractile vacuole membrane tension. The isolated CV promises to be an excellent model system for understanding the molecular mechanisms of the dynamics of biological membrane.

Animals↗
PubMed2001

The influence of commonly prescribed synthetic drugs for peptic ulcer on the pharmacokinetic fate of glycyrrhizin from Shaoyao-Gancao-tang.

The influence of synthetic drugs prescribed for peptic ulcer on the pharmacokinetic fate of glycyrrhizin (GL) from Shaoyao-Gancao-tang (SGT, a traditional Chinese formulation, Shakuyaku-Kanzo-to in Japanese) was investigated in rats. Co-administration of histamine H2-receptor antagonist (cimetidine) and anticholinergic drug (scopolamine butyl bromide) with SGT didn't influence the area under the plasma concentration-time curves (AUC) of glycyrrhetic acid (GA), an active metabolite derived from GL in SGT. The AUC of GA from SGT were significantly reduced by co-administration of synthetic drugs commonly used for peptic ulcer in a triple therapy (OAM), a combination of a proton pump inhibitor (omeprazole) and two antibiotics (amoxicillin and metronidazole). We found that the reduction of AUC in OAM treatment was due to the antibacterial effect of amoxicillin and metronidazole on intestinal bacteria in rat which lead to the decrease of GL-hydrolysis activity. The present study suggests that it may not be a proper way to use triple therapy containing antibiotics simultaneously with SGT for healing of chronic ulcers.

Amoxicillin↗
PubMed2001

A Kampo formulation: Byakko-ka-ninjin-to (Bai-Hu-Jia-Ren-Sheng-Tang) inhibits IgE-mediated triphasic skin reaction in mice: the role of its constituents in expression of the efficacy.

We have demonstrated that oral administration of a Kampo formulation, Byakko-ka-ninjin-to (Bai-Hu-Jia-Ren-Sheng-Tang), inhibited IgE-mediated triphasic skin reaction, including immediate phase response (IPR), late phase response (LPR) and very late phase response (vLPR), in passively sensitized mice with anti-DNP IgE antibody. Variant formulations of Byakko-ka-ninjin-to without Gypsum Fibrosum (Sekko), Glycyrrhizae Radix (Kanzo) or Oryzae Semen (Kobei) attenuated the inhibitory effect as compared with that of Byakko-ka-ninjin-to. The decreased effect of Byakko-ka-ninjin-to without Kanzo was restored by the addition of Kanzo to the variant formulations before oral administration, while the decreased effect of Byakko-ka-ninjin-to without Sekko could not be recovered by the addition of Sekko. Comparison of HPLC profiles of variant formulations without one crude drug with that of original Byakko-ka-ninjin-to revealed that some peaks could be detected only when five constituent crude drugs were simultaneously present during the preparation of Byakko-ka-ninjin-to formulation. Since elimination of Sekko from the Byakko-ka-ninjin-to constituents attenuated the efficacy although it did not show any activity per se, mutual interaction of Sekko with other constituents during the preparation may result in the production of new components. These findings suggest that the effect of Byakko-ka-ninjin-to formulation on cutaneous inflammatory disease can differ from the sum of the effect of the individual constituents.

2,4-Dinitrophenol↗
PubMed2001

Prediction of functional recovery in patients with myocardial infarction after revascularization--comparison of low-dose dobutamine stress echocardiography with fluorine-18 fluorodeoxyglucose positron emission tomography.

The present study investigated the agreement between low-dose dobutamine stress echocardiography (LDDSE) and fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) and compared each technique's ability to detect myocardial viability and predict functional recovery in 30 patients. All patients underwent revascularization, followed by echocardiography 5+/-3 months. Of the 390 segments analyzed by echocardiography before revascularization, 110 (28%) had abnormal wall motion. LDDSE showed viability in 66 sites of the 110 dyssynergic segments and 58 of these viable segments recovered their wall motion. With FDG-PET, 78 of the 110 dyssynergic segments were diagnosed as viable and 62 of these showed improvement of the wall motion. The sensitivities for LDDSE and FDG-PET to assess functional recovery were 84% and 90%, respectively; specificities were 80% and 64%, respectively. Positive predictive values for LDDSE and FDG-PET were 88% and 79%; negative predictive values were 75% and 78%, respectively. Both methods had good sensitivity for detecting improvement in regional function after revascularization, but LDDSE had a higher specificity for detecting viability and a better positive predictive value for left ventricular functional recovery.

Aged↗
PubMed2001

Immunolocalization of aquaporin-8 in rat digestive organs and testis.

Expression of aquaporin-8 mRNA has previously been shown in hepatocytes, pancreatic acinar cells, colon epithelial cells and seminiferous tubules of the testis in the rat by in situ hybridization technique. However, immunolocalization of this water channel has not yet been demonstrated. In the present study, the localization of immunoreactive aquaporin-8 and expression of the mRNA were examined in rat organs (cerebrum, cerebellum, eye, salivary gland, heart, lung, liver, pancreas, esophagus, stomach, jejunum, ileum, colon, testis, ovary, kidney, spleen and lymphnode) by immunohistochemistry using an antibody against aquaporin-8 and ribonuclease protection assay. Aquaporin-8 was distinctly immunolocalized on the apical membranes of pancreatic acinar cells and mucosal epithelium of the colon and jejunum. In the liver, the bile canalicular membrane of hepatocytes was immunostained. In the testis, immunoreactive aquaporin-8 was demonstrated on the luminal side of the seminiferous tubules. At high magnification, the peroxidase reaction products appeared on the ramified cytoplasmic membrane of Sertoli cells surrounding the residual bodies or spermatogenic cells. Specificity of the antibody was verified by Western blot analysis showing a minor approximately 28 kDa band (deduced deglycosylated form of aquaporin-8) and a major approximately 30 kDa band (glycosylated form) in these organs. The intensity of aquaporin-8 immunoreactivity was approximately comparable to that of aquaporin-8 mRNA expression in the liver, pancreas, colon, jejunum and testis. The aquaporin-8 mRNA expression in the hepatocytes was presumed to be closely associated with the structure of bile canaliculi since the message was detected in hepatocytes immediately after isolation from the liver but not in cells following cultivation for three days. The localization of immunoreactive aquaporin-8 indicated functions for this water channel in the secretion of bile and pancreatic juice, and the secretion or absorption of water in the colon and jejunum, and the maturation or liberation of spermatogenic cells in the testis.

Animals↗
PubMed2001

Immunolocalization of aquaporin-9 in rat hepatocytes and Leydig cells.

The aquaporin (AQP)-9 gene was recently isolated from human and rat liver cDNA libraries as a member of the water channel family for water and neutral solutes. Although the expression of AQP9 mRNA has been demonstrated in several organs including the liver and testis by Northern blot analysis, the cellular and subcellular localization of the AQP9 protein remains unclear. In the present light and electron microscopic immunohistochemical study, the localization of the AQP9 immunoreactivity was examined in fifteen kinds of rat organs using an antibody against rat AQP9 synthetic peptide. The antibody immunostained a major band of approximately 33 kDa in the liver by Western blot analysis. Immunoreactivity for AQP9 was found exclusively in the liver and testis among the organs examined. In the liver, positive staining appeared selectively along the space of Disse. Immunoelectron microscopy confirmed the localization of AQP9 on the surface of hepatocyte microvilli facing the space of Disse. In the testis, the plasma membrane of Leydig cells located between seminiferous tubules was conspicuously immunoreactive to the antibody. Intense mRNA expression was detected in the liver and testis but not in other organs by ribonuclease protection assay. These findings suggest a specific role for AQP9 in the transport of water and non-charged solutes in hepatocytes and Leydig cells.

Animals↗
PubMed2001

Increased expression of S100A4 and its prognostic significance in esophageal squamous cell carcinoma.

S100A4 has been implicated in invasion and metastasis of cancer, but prognostic significance of its expression in esophageal squamous cell carcinoma remains unclear. In this study, we examined the expression of S100A4 by Western blot analysis and immunohistochemistry in surgically resected esophageal squamous cell carcinoma. The relationship between S100A4 tissue status and clinicopathological findings was analyzed to assess the prognostic significance of S100A4 in esophageal squamous cell carcinoma. The S100A4 protein level was significantly higher in tumor tissue than in corresponding normal esophageal mucosa (p<0.05) in 22 cases of esophageal carcinoma by Western blot analysis. S100A4 expression was detected in 25% of 52 cases of esophageal squamous cell carcinoma by immunohistochemistry and correlated with the depth of invasion (p<0.05). Patients with S100A4-positive carcinoma had significantly poorer prognosis than those with S100A4-negative carcinoma, which was also true in the cases with deep invasion of the primary cancer (T3, T4) (p<0.01 and p<0.05, respectively). Moreover, S100A4 tissue status remained the only independent prognostic parameter in the multivariate analysis. Our results suggest that S100A4 may play a key role in the progression of esophageal carcinoma and that immunohistochemical detection of S100A4 in the primary tumor may be useful for the prediction of a poor prognosis.

Adult↗
PubMed2001

The metastatic odyssey: the integrin connection.

This article explores the mechanistic basis of carcinoma progression by focusing on the contribution of integrins. Integrins are essential for progression because of their ability to mediate physical interactions with extracellular matrices and their ability to regulate signaling pathways that control actin dynamics and cell movement, and for growth and survival. This article centers on a6 integrins (a6B1 and a6B4), which are receptors for the laminin family of basement membrane components. Numerous studies have implicated these integrins in cancer progression and have provided a rationale for studying the mechanistic basis of their contribution to aggressive disease.

Actins↗
PubMed2001

[Tumor ablation with MRI navigation--a novel method of microwave coagulation therapy for hepatic tumor].

Fifty-eight patients with hepatic tumor which consisted of 22 hepatocellular carcinomas and 36 metastatic liver tumors were treated by microwave coagulation therapy with MRI navigation. The tumors were located in all segments of liver except S1. In 24 cases among them, the abdominal approach was difficult, because the tumors were located just below the diaphragm. These cases were selected for thoracoscope-assisted microwave ablation under MR-guidance across the diaphragm. All MR data were collected on a vertically oriented open MRI system (0.5 T SIGNA SP/i system: GE Medical Systems). The microwave electrode was introduced into the liver through a 14G needle via a percutaneous puncture with real-time MR image navigation. Microwave ablations at 60 W for 60 seconds were repeated several times depending on the tumor size. MR imaging may be employed as a reliable guide for percutaneous puncture. Moreover, sufficient safety margin could be obtained for hepatic tumor ablation. MR-guided microwave thermoablation therapy is a feasible method of treatment for hepatic tumors.

Carcinoma, Hepatocellular↗
PubMed2001

[Four cases of multiple liver metastasis of colorectal cancer treated with hepatic resection after chemotherapy].

Four cases of multiple liver metastasis of colorectal cancer treated with hepatic resection after chemotherapy were investigated. The 4 patients consisted of 3 males and 1 female with a mean age of 67.8 years. Two patients underwent systemic chemotherapy, and the other 2 received hepatic arterial infusion chemotherapy. The effect was PR in all patients, and mean duration until resection was 8.5 months. One patient had lung metastasis and one had recurrence in a local lesion and residual liver after hepatic resection, but all patients remain alive. The longest survival periods in 4 patients who underwent hepatic resection and 13 who did not were 32 and 24 months, respectively. It is suggested that hepatic resection after chemotherapy for multiple liver metastasis of colorectal cancer may be useful for improvement of outcome.

Aged↗
PubMed2001

[Hepatic infusion of docetaxel using PEIT for a patient with stage IV breast cancer].

Hepatic infusion of docetaxel using PEIT was performed for a patient with stage IV breast cancer. Docetaxel was effective to a solitary liver metastatic lesion. A 64-year-old woman was admitted to our hospital because of a left breast mass that was bleeding. She was diagnosed with stage IV breast cancer. Surgery was performed on February 16th. The pathological diagnosis was invasive ductal carcinoma, and hormone receptors were negative. Two weeks after operation, monthly docetaxel injections were given together with doxifluidine 400 mg/day p.o., cyclophosphamide 50 mg/day p.o., and fadrozole hydrochloride hydrate 2 mg/day p.o. After two courses, hepatic infusion of docetaxel was performed using PEIT after informed consent. The patient's high serum CEA and CA15-3 level returned to the normal range. A metastatic lesion on CT changed to a cystic pattern. These results suggest that PEIT is worth trying in patients with solitary liver metastasis from breast cancer.

Antineoplastic Agents, Phytogenic↗
PubMed2001

[Wood creosote: a historical study and its preparation in combination with herbal drugs].

Two kinds of creosote have been found based on historical evidence of the medicinal uses and origins. One is wood creosote, and distillate of wood-tar containing guaiacol and creosol. The other type of creosote is coal-tar creosote, obtained from coal-tar, containing naphthalene and anthracene as the major constituents. Wood creosote was prepared for the first time in Germany in 1830 and was used for medicinal purposes. It had been listed officially in the German, American, and Japanese Pharmacopoeia as an antibacterial agent for the treatment of pulmonary tuberculosis, diarrhea, and external injury. In recent days, it has been deleted from the Pharmacopoeia in Western countries and not officially used for medicinal purposes. However, wood creosote is still been listed in the Japanese Pharmacopoeia and is used for the treatment of diarrhea. Since the interest of common people in herbal medicines and self-medication has been increasing, the use of wood creosote has also been modified in combination with some herbal drugs, "Seiro-gan" especially is quite popular in Japan as a self-medication for digestive trouble, including food poisoning or diarrhea.

Creosote↗
PubMed2001

[Incidence of systolic pulmonary venous flow reversal in patients with mitral valve prolapse: influence of the prolapse site].

OBJECTIVES: Systolic pulmonary venous flow reversal identified by pulsed Doppler echocardiography is useful for the diagnosis of severe mitral regurgitation. The direction of the mitral regurgitant jet in severe mitral regurgitation significantly influences the systolic pulmonary venous flow reversal in an experimental model. This study investigated the influence of the site of mitral valve prolapse on the incidence of systolic pulmonary venous flow reversal in patients with severe mitral regurgitation using transthoracic color Doppler echocardiography. METHODS: This study included 59 consecutive patients with severe mitral regurgitation (regurgitant fraction > 50%) due to mitral valve prolapse. Exclusion criteria were left ventricular ejection fraction < 45%, non sinus rhythms, associated aortic valve disease, bileaflet prolapse, and inadequate Doppler recordings. Right upper pulmonary venous flow was recorded and regurgitant fraction of mitral regurgitation measured by transthoracic color Doppler echocardiography. The sites of mitral valve prolapse were confirmed at operation in all patients. RESULTS: The incidence of systolic pulmonary venous flow reversal was 78% (14/18) in the patients with anterior leaflet prolapse, 82% (9/11) in the patients with medial commissure prolapse, 75% (12/16) in the patients with posterior middle scallop prolapse, 20% (2/10) in the patients with posterior medial scallop prolapse, and 25% (1/4) in the patients with posterior lateral scallop prolapse. There were no significant differences in regurgitant fraction between the five groups. The incidence of systolic pulmonary venous flow reversal was significantly lower in the patients with posterior medial scallop prolapse compared to the other sites of mitral valve prolapse (p < 0.01). CONCLUSIONS: Assessment of the severity of mitral regurgitation by systolic pulmonary venous flow reversal using transthoracic color Doppler echocardiography may be underestimated in patients with prolapse of the posterior medial scallop.

Aged↗
PubMed2000

Development of rabbit parthenogenetic oocytes and nuclear-transferred oocytes receiving cultured cumulus cells.

The present study determined a suitable parthenogenetic activation procedure for rabbit oocytes and examined the developmental potential of enucleated oocytes receiving cultured cumulus cells. Unfertilized oocytes recovered from superovulated rabbits were activated with one or two sets of electrical pulses, with or without subsequent administration of 6-dimethylaminopurine (6-DMAP). The proportion of oocytes treated with one or two sets of electrical pulses and 6-DMAP that cleaved (87% and 98%, respectively) and developed into blastocysts (77% and 85%, respectively) was significantly higher (P < 0.05) than those activated with electrical pulses alone (30% and 42% for cleavage, 7% and 17% for blastocysts). Cumulus cells separated from ovulated oocytes obtained from mature rabbits were cultured for three to five passages and then induced to quiescence by serum starvation before nuclear transfer. The enucleated oocytes receiving cumulus cells were activated with electrical pulses followed by the addition of 6-DMAP, and cultured in vitro for 5 to 6 d or transferred to pseudopregnant recipient females 1 d after activation. Of 186 nuclear-transferred oocytes, 123 (66%) cleaved and 42 (23%) developed into blastocysts. After transfer of 174 nuclear-transferred oocytes to 8 recipient females, a total of 3 implantation sites were observed in 3 recipient females but no fetuses were obtained.

Adenine↗