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T Tani

Publications and source records attributed to T Tani.

At least 163 records · Page 9Linked to original sources
PubMed1997

Effect of a glutamine-enriched diet on small bowel allograft during immunosuppressive therapy.

The effect of an orally administered glutamine-enriched elemental diet was examined following orthotopic small bowel allotransplantation using Brown Norway rats as donors and Lewis rats as recipients. The recipients was treated with FK 506 and randomized to receive glutamine-free elemental enteral diet solution (glutamine-free group), glutamine-enriched elemental diet solution containing 7500 mg of glutamine per 100 g diet (glutamine-enriched group) or standard chow (chow group) ad libitum for 7 d. There were no histological changes due to resection. Weight loss in the glutamine-enriched group was significantly less than that of the chow group. Both plasma glutamine levels and the ratio of glutamine to total amino acids in the homogenate of the graft mucosa of the glutamine-enriched group were significantly higher than those of the glutamine-fee group. Villous height and crypt depth were significantly decreased in the glutamine-free group. The BrdU labeling index in the graft epithelium and alkaline phosphatase activity in the homogenate of the graft mucosa of the glutamine-enriched group were significantly higher than those of the glutamine-free group. Therefore, orally administered glutamine-enriched elemental diet appears to promote the regeneration and differentiation of the graft mucosa following small bowel allotransplantation.

Aging↗
PubMed1997

Reflexes evoked in human erector spinae muscles by tapping during voluntary activity.

We studied the stretch reflexes, an early R1 and a late R2, by tapping the voluntarily contracted erector spinae muscles and recording from the same spinal level with the subject in the prone position. The onset latencies increased progressively towards the caudal level from 8.8 +/- 0.7 ms at T5-6 to 15.9 +/- 1.1 ms at L4-5 for R1, and from 33.3 +/- 2.7 ms at T5-6 to 49.1 +/- 2.8 ms at L4-5 for R2. The latency changed significantly (P < 0.05) between two adjacent segments from T5-6/T6-7 through L1-2/L2-3 for R1 and T5-6/T6-7 through L3-4/L4-5 for R2. When recorded remote from the stimulus site, R1, considered segmental in origin, showed, as expected, only a small latency change consistent with the time required for the mechanical event to propagate to the recording site. In contrast R2 was shorter in latency with more rostral stimulation irrespective of the distance to the recording sites. This finding implies a centripetal propagation of the afferent impulse along the central pathway, which shortens with more rostral site of stimulation. Of the two components, the more reproducible R1 has a potential diagnostic value for segmental evaluation of thoracic nerve root compression and truncal neuropathies.

Adult↗
PubMed1997

Isolation and molecular characterization of mRNA transport mutants in Schizosaccharomyces pombe.

Nucleocytoplasmic transport of mRNA is essential for eukaryotic gene expression. However, how mRNA is exported from the nucleus is mostly unknown. To elucidate the mechanisms of mRNA transport, we took a genetic approach to identify genes, the products of which play a role in that process. From about 1000 temperature -sensitive (ts- or cs-) mutants, we identified five ts- mutants that are defective in poly(A)+ RNA transport by using a situ hybridization with an oligo(dT)50 as a probe. These mutants accumulate poly(A)+ RNA in the nuclei when shifted to a nonpermissive temperature. All five mutations are tightly linked to the ts- growth defects, are recessive, and fall into four different groups designated as ptr 1-4 (poly(A)+ RNA transport). Interestingly, each group of mutants has a differential localization pattern of poly(A)+ RNA in the nuclei at the nonpermissive temperature, suggesting that they have defects at different steps of the mRNA transport pathway. Localization of a nucleoplasmin-green fluorescent protein fusion suggests that ptr2 and ptr3 have defects also in nuclear protein import. Among the isolated mutants, only ptr2 showed a defect in pre-mRNA splicing. We cloned the ptr2+ and ptr3+ genes and found that they encode Schizosaccharomyces pombe homologues of the mammalian RCC1, a guanine nucleotide exchange factor for RAN/TC4, and the ubiquitin-activating enzyme E1 involved in ubiquitin conjugation, respectively. The ptr3+ gene is essential for cell viability, and Ptr3p tagged with green fluorescent protein was localized in both the nucleus and the cytoplasm. This is the first report suggesting that the ubiquitin system plays a role in mRNA export.

Amino Acid Sequence↗
PubMed1997

The prp1+ gene required for pre-mRNA splicing in Schizosaccharomyces pombe encodes a protein that contains TPR motifs and is similar to Prp6p of budding yeast.

The prp (pre-mRNA processing) mutants of the fission yeast Schizosaccharomyces pombe have a defect in pre-mRNA splicing and accumulate mRNA precursors at a restrictive temperature. One of the prp mutants, prp1-4, also has a defect in poly(A)+ RNA transport. The prp1+ gene encodes a protein of 906 amino acid residues that contains 19 repeats of 34 amino acids termed tetratrico peptide repeat (TPR) motifs, which were proposed to mediate protein-protein interactions. The amino acid sequence of Prp1p shares 29.6% identity and 50.6% similarity with that of the PRP6 protein of Saccharomyces cerevisiae, which is a component of the U4/U6 snRNP required for spliceosome assembly. No functional complementation was observed between S. pombe prp1+ and S. cerevisiae PRP6. We examined synthetic lethality of prp1-4 with the other known prp mutations in S. pombe. The results suggest that Prp1p interacts either physically or functionally with Prp4p, Prp6p and Prp13p. Interestingly, the prp1+ gene was found to be identical with the zer1+ gene that functions in cell cycle control. These results suggest that Prp1p/Zer1p is either directly or indirectly involved in cell cycle progression and/or poly(A)+ RNA nuclear export, in addition to pre-mRNA splicing.

Alleles↗
PubMed1997

Improving effect of carteolol on bodyweight and carbohydrate and lipid metabolic responses in the OLETF rat.

1. Carteolol, a non-selective beta-blocker with intrinsic sympathomimetic activity, admixed in a pellet diet was administered to Otsuka Long-Evans Tokushima Fatty (OLETF) rats, an animal model of spontaneous non-insulin-dependent diabetes mellitus with mild obesity. A high dose of carteolol (0.02%) suppressed bodyweight gain without affecting food and water consumption until the appearance of glycosuria. Carteolol tended to reduce the cumulative incidence of glycosuria at 26 weeks after the beginning of administration (55, 17 and 25% in control rats, and in rats fed a low (0.002%) and high dose of carteolol, respectively). 2. At the 26th week of administration, the high dose of carteolol decreased visceral fat weight, such as that of retroperitoneal and epididymal adipose tissue, whereas the liver and the kidney were not affected. 3. Although plasma glucose and triglyceride levels in non-fasted rats were elevated with age, carteolol tended to delay the increases in those parameters. Carteolol suppressed the increase in plasma glucose levels, which indicate the diabetic pattern, in a 25th week oral glucose tolerance test. 4. These findings indicate that carteolol induces improvements in bodyweight and carbohydrate and lipid metabolism in an obese condition. Consequently, carteolol may be useful for the treatment of hypertension with obesity in order to prevent cardiovascular events.

Adipose Tissue↗
PubMed1997

Comparison of acute physiology and chronic health evaluation III and II for prediction of mortality in multiple organ failure patients treated by plasma exchange.

This study examined the efficacy of a different scoring system for multiple organ failure (MOF) patients treated by plasma exchange (PE). Twenty-five patients with MOF resulting from fulminant hepatitis who had been treated by PE for a total number of 91 PEs in a consecutive period of 22 months were included in our study. Data were collected from each patient to compute acute physiology and chronic health evaluation (APACHE) II and APACHE (AP) III scores. The sensitivity, specificity, and correct prediction of outcomes were measured. The correct prediction of outcomes was 86.5%in AP III and 77.5% in AP II. For the prediction of patient mortality, the AP III system seems to be more reliable than AP II.

APACHE↗
PubMed1997

Theoretical background of effect mechanism by extracorporeal immunomodulation.

Therapeutic plasmapheresis has usually been applied to diseases with unknown causes. Clear analysis of the mechanism of the effect that apheresis has on diseases derived from unknown causes has not been completed. The effect of leukocytapheresis on ulcerative colitis (UC) or rheumatoid arthritis (RA) also lacks clear analysis, but removal of 10(10) adhesive cells resulted in the suppression of both acute and chronic inflammatory reactions. The number of cells removed was not unreasonable for efficacy. A quite acceptable explanation is that the cells activated in the inflammatory lesions are more adhesive than nonactivated cells. However, only a few minutes of contact with the surface of the device can activate blood immune cells. All of the apheresis therapies, not only leukocytapheresis, should be evaluated for their efficacies, excluding the effects of contact activation. According to results presently available, the suppressive effect of leukocytapheresis on RA or UC is through to depend upon the removal of activated inflammation related cells that might transfer inflammatory signals. It may be that those cells removed are bound because of cell stimulation caused by microorganisms or foreign bodies.

Arthritis, Rheumatoid↗
PubMed1997

Blood purification for critical care medicine: endotoxin adsorption.

Many kinds of blood purifying technologies have been applied to the treatment of critically ill patients since 1979 when plasma exchange with hollow-fiber membranes was developed. These technologies have been applied not only to the removal of toxic substances, but also to the treatment of objective diseases and the removal of the factors relating to the associated inflammation. This article summarizes these methods and their efficacies for critically ill patients, especially those with severe sepsis. Attempts have been made to remove endotoxin, the main cause of sepsis, from the circulation using polymyxin B immobilized fiber, charcoal hemoperfusion, and plasma or whole blood exchange. Attempts have also been made to remove proinflammatory cytokines, eicosanoides, and coagulative factors from the circulation in the human body. Continuous hemofiltration or hemodiafiltration is the representative technology. The efficacy of these methods has been established, but several issues remain unresolved. All methods of the treatment of severe sepsis are discussed with reference to treatment indications, efficacy, and outcome parameters. In particular, the clinical results of endotoxin removal with polymyxin B immobilized fiber are summarized in this article.

Adsorption↗
PubMed1997

gamma-Pyrones from Gonystylus keithii, as new inhibitors of parathyroid hormone (PTH)-induced Ca release from neonatal mouse calvaria.

New gamma-pyrones, 9'-oxopodopyrone (3) and 8-methyl-9'-oxopodopyrone (4) were isolated from the leaves of Gonystylus keithii, along with known gamma-pyrones, 10'-oxopodopyrone (1) and 8-methyl-10'-oxopodopyrone (2). These gamma-pyrones markedly inhibited the bovine parathyroid hormone (PTH)-induced Ca release from neonatal mouse calvaria in vitro. It is the first time that gamma-pyrones showed inhibitory effects on bone resorption, and these compounds may be seed compounds of new drugs for osteoporosis.

Animals↗
PubMed1997

Pyrrole butyric acid derivatives as inhibitors of steroid 5 alpha-reductase.

A series of pyrrole butyric acid derivatives was synthesized and evaluated for inhibitory activity on human and rat steroid 5 alpha-reductase in vitro and ex vivo. 3-Benzoyl-4-alkylpyrrole-1-butyric acids and 1-methyl-2-alkyl-3-benzoylpyrrole-5-butyric acid derivatives were effective inhibitors. Structure activity relationships were evaluated among the 37 compounds synthesized. Compound 37 (HQL-1069) shows potent inhibitory activities against both rat and human 5 alpha-reductase.

5-alpha Reductase Inhibitors↗
PubMed1997

Medicinal foodstuffs. VI. 1) Histamine release inhibitors from kidney bean, the seeds of Phaseolus vulgaris L.: chemical structures of sandosaponins A and B.

Two new olean-12-ene-type triterpene oligoglycosides, named sandosaponins A and B, were isolated from kidney bean, the seed of Phaseolus vulgaris L., together with three known saponins, soyasaponins I and V and dehydrosoyasaponin 1. The structures of sandosaponins A and B were determined on the basis of chemical and physicochemical evidence, which included the chemical derivation of sandosapogenol from a known sapogenol, soyasapogenol B. Five saponins obtained from kidney bean were found to inhibit histamine release from rat exudate cells induced by an antigen-antibody reaction and, among them, sandosaponins A and B showed the most potent inhibitory activity.

Animals↗
PubMed1997

Expression of MAGE genes in colorectal carcinomas.

The human genes MAGE-1 and MAGE-3 encode tumor rejection antigens recognized on melanoma cells by cytotoxic T lymphocytes (CTL). These antigens are potentially useful as targets for specific immunotherapy. Expression of MAGE genes in some malignant tumors has been reported, but MAGE gene expression in colorectal carcinomas has not been studied adequately. Therefore, we studied MAGE-1,2,3, and 4 a/4 b expression at the mRNA level, in 40 cases of surgery for colorectal carcinoma, using the reverse transcription polymerase chain reaction (RT-PCR). MAGE-1,2,3, and 4 a/4 b genes were expressed in 3 (7.5%), 6 (15.0%), 13 (32.5%), and 5 (12.5%), respectively, of these 40 cases. A total of 19 of the 40 samples (47.5%) expressed at least one of the MAGE genes. The relationships between clinicopathologic factors and MAGE gene expression were also examined. The frequency of lymph node metastasis was significantly higher in MAGE-3-positive than in MAGE-3-negative cases (p < 0.05). All these cases classified as Duke's D expressed the MAGE-3 gene. This rate of expression was significantly higher than that for all other the Duke's classifications together (p < 0.05). Our findings suggest that MAGE-specific immunotherapy against colorectal carcinomas may be feasible.

Aged↗
PubMed1997

Waveform changes due to conduction block and their underlying mechanism in spinal somatosensory evoked potential: a computer simulation. Technical note.

Based on a square-wave solid-angle analysis, a simplified mathematical model was produced for computing a sequence of potential change in a volume conductor generated by an impulse traveling along a nerve fiber. A conduction block was simulated as a phenomenon in which a depolarization wavefront stops traveling when it reaches a certain point, although the following repolarization wavefront continues to travel until it reaches the same point. The spinal somatosensory evoked potential (SSEP) was produced as an algebraic sum of simulated nerve fiber action potentials (NFAPs). With a conduction block, an NFAP that was normally triphasic showed a positive-negative diphasic wave with reduced negativity at the point of the block, diphasic waves with enhanced negativity at points immediately preceding the block, and initial-positive waves alone or abolition of any wave at points beyond the block. The absence of their terminal-positive phases paradoxically enhanced the negative peak of the spinal SSEPs in a partial block that involved only the constituent fastest fibers, because phase cancellation of the phases between the terminal-positive phases of the fastest fibers and the negative phases of the slower fibers, which normally happens, failed to occur. At the points immediately preceding the block, the identical mechanism sustained the spinal SSEP enhancement even when every fiber was included in the block. The computer model predicted that localization of the precise site of conduction block can be achieved by demonstrating an abrupt reduction in the amplitude of the spinal SSEP, which is accompanied by an increased negative wave caudally and an enhanced monophasic positive wave rostrally.

Computer Simulation↗
PubMed1997

Distinct changes in the laminin composition of basement membranes in human seminiferous tubules during development and degeneration.

We studied the distribution of laminin (Ln) chains and their integrin (Int) receptors in normal developing and adult and in atrophied human testes by using immunohistochemistry. Immunostaining for EHS Ln and type IV collagen was used to identify basement membranes (BMs). In the BM of seminiferous epithelium of fetal testis, a panel of monoclonal antibodies showed immunoreactivity for Ln alpha 1-, alpha 2-, beta 1-, beta 2- and gamma 1-chains, suggestive of the presence of Lns 1 to 3. In BM of adult seminiferous epithelium with active spermatogenesis, immunoreactivity for Ln beta 2- and gamma 1-chains was found but not for Ln alpha-chains, suggesting a complex of Ln chains not compatible with any known trimers. Instead, with polyclonal Ln antiserum and monoclonal antibody to type IV collagen, a distinct BM-like reactivity was seen. In atrophied testes, prominent immunoreactivities for Ln chains, compatible with Lns 1 to 3, were seen in the thickened BM of seminiferous tubules, hence suggestive of reappearance of fetal Lns. Among the subunits of Ln-binding Int receptors in fetal seminiferous tubules, a strong immunoreactivity for Int beta 1- and Int alpha 6-subunits was seen throughout the seminiferous epithelium, other Int subunits being found in interstitial cells. In the adult and atrophied testes, immunoreactivities for Int beta 1- and Int alpha 6-subunits were seen to be confined to the basal aspect of the seminiferous epithelium whereas immunoreactivities for Int alpha 1-, alpha 2-, alpha 3- and beta 4-subunits were seen in the myoid cells. The results show that both maturation and degenerative changes of human testes are accompanied by distinct changes in the Ln expression of BM of seminiferous epithelium, which appears to accompany epithelial differentiation of the Sertoli cells. Furthermore, they suggest the presence of a novel Ln trimer in BM of adult human seminiferous tubules.

Adult↗
PubMed1997

Protective effect of nafamostat mesilate in early wound healing.

BACKGROUND: Tensile strength in rat ileal anastomosis is diminished after injection with superoxide dismutase. We have studied the immunohistochemistry of extracellular matrix to investigate changes associated with this loss of tensile strength. A serine proteinase inhibitor, Nafamostat mesilate, was used to evaluate its potential for maintaining tensile strength. STUDY DESIGN: Four groups of rats underwent ileal anastomosis, Groups 1 and 2 were controls. Groups 3 and 4 were given superoxide dismutase and Nafamostat mesilate, respectively, after anastomosis. RESULTS: In controls, groups 1 and 2, tensile strength decreased to 58 percent and 57 percent, respectively, of the initial value measured immediately after anastomosis 1 day postoperatively and both dropped to 33 percent 3 days postoperatively. After 5 days, tensile strength recovered to 83 percent of initial value. In comparison with controls, administration of superoxide dismutase significantly attenuated the loss of tensile strength on day 1 (94 percent of initial value, p < 0.01) and on days 3, 5 and 7 (p < 0.05). Similar results were found after administration of Nafamostat mesilate on days 3 and 5 (p < 0.05). In group 1, degradation of the collagen layer in the anastomosis was observed, with disappearance of immunostaining for fibronectin and vitronectin on day 3. In both groups 3 and 4, these changes were significantly attenuated with intense immunostaining for plasminogen activator inhibitor-1; fibronectin and vitronectin were seen particularly among collagen fibers on both sides of the anastomosis. CONCLUSIONS: These findings suggest that degradation of extracellular matrix causes loss of tensile strength early after anastomosis. Nafamostat mesilate may be clinically useful to prevent breakdown of intestinal anastomoses.

Anastomosis, Surgical↗
PubMed1997

[Role of endothelin-B receptors in the pulmonary circulation].

Endothelin-1 (ET-1) is a potent vasoactive peptide and is thought to play an important role in the regulation of vascular tone. ET-1 can both constrict blood vessels, via endothelin-A (ET-A) receptors in vascular smooth muscle cells, and dilate then via endothelin-B (ET-B) receptors in endothelial cells in the systemic circulation. To determine the role of ET-B receptors in the pulmonary circulation, we examined the hemodynamic effects of a selective ET-B receptor agonist (IRL 1620) in rats. In rat lungs perfused with a salt solution, IRL 1620 caused pulmonary vasoconstriction in a dose-dependent manner. In lungs perfused with a hypoxic half-blood solution (10% O2), doses of IRL 1620 less than 10 nM caused pulmonary vasodilation, but higher doses caused pulmonary vasoconstriction. IRL 1620 caused transient vasodilation of the systemic circulation at every dose used (0.1, 1, and 5 nmol/kg) in anesthetized rats. In contrast, the effects of IRL 1620 on the pulmonary circulation varied with the dose. Small doses (0.1 or 1 nmol/kg) caused pulmonary vasodilation, but a higher dose (5 nmol/kg) caused pulmonary vasoconstriction. These results show tachyphylaxis in the pulmonary vasodilator response to IRL 1620, but not in the systemic vasodilator response. The present data show the dual action (vasoconstriction and vasodilation) of ET-B receptors.

Animals↗
PubMed1997

Evaluation of plasma (1-->3)-beta-D-glucan measurement by the kinetic turbidimetric Limulus test, for the clinical diagnosis of mycotic infections.

The present multicentre clinical study was conducted to assess the clinical utility of a new diagnostic method for deep mycosis in which (1-->3)-beta-D-glucan, a fungal cell wall component existing in plasma, was quantitatively measured by the kinetic turbidimetric Limulus test (WB003). Plasma (1-->3)-beta-D-glucan concentrations were 0.57 +/- 0.10 microgram/l in 92 healthy subjects and 0.62 +/- 0.32 microgram/l in 26 patients with non-mycotic diseases (disease control group). In comparison with these healthy subjects and patients with non-mycotic diseases, patients with mycosis had significantly higher plasma (1-->3)-beta-D-glucan concentrations: 19.63 +/- 73.28 micrograms/l in 12 patients with candidaemia, 11.28 +/- 21.42 micrograms/l in 7 patients with urinary Candida infection, 4.84 +/- 12.71 micrograms/l in 5 patients with pulmonary candidiasis, and 12.21 +/- 31.31 micrograms/l in 4 patients with invasive pulmonary aspergillosis. On the statistical analysis of these data, a cut-off value was set at 1.0 microgram/l. Using this cut-off value, 3 patients with pulmonary cryptococcosis and 4 patients (4/6) with pulmonary aspergilloma were all negative with low plasma (1-->3-beta-D-glucan levels. The test WB003 provided equivalent or higher efficiency of diagnosis of candidiasis and aspergillosis, in comparison with commercially available antigen detection kits, demonstrating its utility as a diagnostic reagent. It may also be useful in assessing therapeutic effectiveness when used periodically after treatment.

Adolescent↗