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M Tori

Publications and source records attributed to M Tori.

At least 19 recordsLinked to original sources
PubMed2001

Sesquiterpenes and monoterpenes from the bark of Inula macrophylla.

Eleven new sesquiterpenes (1--11) and two thymol derivatives (12, 13), along with 12 known sesquiterpenes and monoterpenes, were isolated from the bark of Inula macrophylla. Their structures were determined on the basis of spectral evidence (especially by HREIMS and 2D NMR) as well as chemical transformations. The structure of macrophyllic acid A (1) was confirmed by X-ray analysis, and the absolute configuration of 1 was determined on the basis of the appropriate chemical conversions and the application of a modified Mosher's method.

Crystallography, X-Ray↗
PubMed2001

Thymol derivatives from Eupatorium fortunei.

Sixteen new thymol derivatives have been isolated from Eupatorium fortunei and their structures determined based on spectroscopic data. They were classified into three groups (i-iii) depending on the oxidation levels: (i) one oxygen function at the 9-position, (ii) two oxygen functions at the 8- and 9-positions, and (iii) three oxygen functions at the 8-, 9-, and 10-positions. The hydroxyl groups are acylated with tigloyl, angeloyl, acetyl, isobutyryl, 3-methyl-2-butenoyl, or 2-methylbutyryl moieties. The compounds having chiral centers showed no specific rotation and exist as racemic mixtures.

Chromatography, High Pressure Liquid↗
PubMed2000

Initial T-cell activation required for transplant vasculopathy in retransplanted rat cardiac allografts.

BACKGROUND: A precise understanding of immunological mechanisms is needed to prevent transplant vasculopathy. METHODS: The developing process of transplant vasculopathy was investigated by retransplanting rat cardiac allografts and measuring the expressions of 21 different genes inside the retransplanted allografts under nonimmunosuppressive conditions. RESULTS: Significant transplant vasculopathy developed if WKY hearts were grafted to LEW and retransplanted to WKY 5 days after the initial grafting, but it did not in allografts retransplanted 3 days after the initial grafting. The disease did not progress in retransplanted isografts or if nude rats were used as the initial recipients. However, the development of transplant vasculopathy was not affected by changing the second recipients to the F1 progeny of donor x recipient or to nude animals. Among the expressions of 21 different genes observed in allografts at 1, 14, 30, or 60 days after retransplantation, those of T-cell activation-related genes, such as interferon-y and Fas ligand, showed the earliest and the most dramatic difference between 3- and 5-day-retransplanted allografts whereas macrophage/monocyte activation-related genes showed little difference. Furthermore, reverse transcription-polymerase chain reaction analyses of allografts retransplanted to nude animal indicated that T cells of the initial recipient origin survive and remain activated even 60 days after retransplantation. CONCLUSIONS: The T-cell response occurring between 3 and 5 days after grafting was identified as the critical parameter to the disease progression. Once alloreactive T cells enter a graft, they may be able to survive a long period and promote chronic rejection.

Animals↗
PubMed2000

Importance of donor-derived lymphocytes in the protection of pancreaticoduodenal or islet grafts from recurrent autoimmunity: a role for RT6+NKR-P1+ T cells.

BACKGROUND: A rat pancreas transplantation model with insulin-dependent diabetes mellitus (IDDM) recurrence was established using a Wistar-Furth (WF; RT1u, RT6.2) rat as a donor and diabetes-prone (DP; RT1u, rt6.1 gene carrier) BioBreeding rat as a recipient. Interestingly, NKR-P1+TCRalphabeta+ (NKT) cells have recently been reported to have immunoregulatory functions in preventing autoimmune diabetes. The purpose of this study was to specifically examine the contribution of NKT cells in the prevention of IDDM recurrence. METHODS: Graft survivals with or without anti-intercellular adhesion molecule-1/leukocyte function-associated antigen-1 monoclonal antibodies were examined comparing pancreaticoduodenal (PD) transplantation with islet transplantation or pancreas-alone transplantation excluding duodenum and peripancreatic lymph nodes, in an IDDM recurrent model. The cells of the spleen were analyzed by flow cytometry (including intracellular interleukin (IL)-4 analysis), and serum cytokine levels (IL-4 and interferon-gamma) were determined by enzyme-linked immunosorbent assays (ELISA). RESULTS: Only those DP recipients transplanted with PD grafts with monoclonal antibody treatment were free from IDDM. Flow cytometric analyses of spleen cells showed that NKT cells in them, compared with those in the recurrent DP recipients (mean <7%), increased significantly (13.7+/-3.1% in the total splenic T cells), most of which (85.9+/-4.3%) were derived from the donor (RT6.2+). The absolute number of RT6+NKT cells significantly increased in the nonrecurrent DP recipients, whereas that of RT6-NKT cells was similar with those of the other recurrent DP recipients. These RT6+NKT cells were predominantly CD4+ and showed significantly more expressions of intracellular IL-4 than the other T cells. By ELISA, serum interferon-gamma was not detectable (< 13 pg/ml) in any of the rats. However, IL-4 was detected at 111.6+/-47.8 pg/ml only in the nonrecurrent DP recipients. CONCLUSIONS: Unlike islet or pancreas-alone transplants, NKT cells, especially RT6+NKT cells derived from PD grafts, may have an important immunoregulatory function of preventing IDDM recurrence, involving a Th2 deviation.

ADP Ribose Transferases↗
PubMed2000

Cyclization into hydrindanones using samarium diiodide

Samarium(II) iodide has been employed to promote vinylogous pinacol coupling reaction of aldehyde onto alpha,beta-unsaturated ketones. The diastereoselectivity of 6-endo products was changed by addition of a proton source and/or HMPA and by the reaction temperature. The cyclization reactions described herein provide a general approach to the syntheses of 3,3-dimethylhydrindanes with a cis-relationship between the OH at C-4 and the proton at C-3a with good diastereoselectivity and under mild reaction conditions.

Journal Article↗
PubMed2000

Macrophyllols A and B, two unusual novel sesquiterpene and monoterpene dimers from the bark of Inula macrophylla.

[structure: see text] Two novel sesquiterpene and monoterpene dimers, macrophyllols A (1) and B (2), were isolated from the bark of Inula macrophylla. Their structures were determined on the basis of spectral evidence (especially HREIMS and 2D NMR) as well as chemical transformation. The structure of macrophyllol A (1) was confirmed by X-ray analysis. The possible biosynthetic pathways of macrophyllols A (1) and B (2) are discussed.

Dimerization↗
PubMed2000

Four alkaloids, lucidine B, oxolucidine A, lucidine A, and lucidulinone from Lycopodium lucidulum.

The structures of four alkaloids extracted from Lycopodium lucidulum (Lycopodiaceae) were established by X-ray and 2D NMR spectroscopic analyses. The dihydro-derivative of oxolucidine A, which was obtained by NaBH4 reduction of oxolucidine A, was treated with p-bromobenzoyl chloride to afford crystals, whose X-ray crystallographic analysis established the stereostructure, including the absolute configuration. The 2D NMR spectra of tetrahydrodeoxylucidine B were fully analyzed to establish the full structure of lucidine B, and the hitherto unknown stereochemistry at the C-14 position was established as beta-H. The structure of a new alkaloid, lucidulinone, was determined by spectroscopic analysis to be luciduline lactam.

Alkaloids↗
PubMed2000

Active cell migration in retransplanted rat cardiac allografts during the course of chronic rejection.

BACKGROUND: Chronic allograft vasculopathy (CAV) is caused by the infiltration of host immune cells to a graft, but it has been technically difficult to monitor the movements of the cells in graft rejection. METHODS: We used a male-specific gene, SRY, as a marker to investigate the dynamics of host cells in a model of CAV in which immunosuppression was unnecessary and anti-male responses were practically negligible. Fluorescent-based real-time quantitative polymerase chain reaction (PCR) was adapted to estimate the fraction of host cells in a graft by the ratio of SRY to IL-2 gene. Using this technique, we studied the turnover and migration of host cells during the course of CAV progression by retransplanting female allografts from male to female or from female to male rats. RESULTS: We detected histologic CAV 60 days after retransplantation in allografts retransplanted to the F(1) progeny of donor x recipient on the 5th day, but not in those retransplanted on the 3rd day, regardless of the mismatches in the genders. Most of the initial infiltrating cells disappeared rapidly in both cases. The fraction of migrating cells from the second recipient, however, continuously increased in allografts developing CAV, and 60 days after retransplantation exceeded 50%, whereas it stayed at 5% to 15% in those not developing CAV. ED-1-positive macrophages/monocytes were likely candidates for the migrated cells. CONCLUSION: We have developed a simple method to measure the migration of host cells into a graft. This technique was useful, at least in certain rat strains, to investigate the cellular mechanisms of chronic cardiac allograft rejection.

Animals↗
PubMed1999

Model of mouse pancreaticoduodenal transplantation.

Our technical procedure for mouse pancreaticoduodenal transplantation is described. A number of methods were attempted. Among them, a modification of S. Lee's method was thought to be the most successful procedure, which was performed with end-to-side anastomosis of the donor portal vein to the inferior vena cava and that of the donor aortic patch to the aorta. Even with this method, however, arterial thrombosis or venous stenosis of the anastomoses was inevitable without the use of some devices as well as special skills in microsurgery.

Anastomosis, Surgical↗
PubMed1999

Significant role of intragraft lymphoid tissues in preventing insulin-dependent diabetes mellitus recurrence in whole pancreaticoduodenal transplantation.

Graft recurrence of insulin-dependent diabetes mellitus (IDDM) was examined. Islet transplantation or pancreas-alone transplantation excluding the duodenum and peripancreatic lymph nodes was compared with whole pancreaticoduodenal transplantation. A Wistar Furth (WF; RT1(u), RT6.2) to major histocompatibility complex (MHC)-compatible diabetes-prone (DP; RT1(u), RT6.1 gene carrier)-biobreeding (BB) rat transplantation model was used. Only DP recipients that had been transplanted with whole pancreaticoduodenal grafts were free from IDDM recurrence (>60 days postgrafting) when treated with anti-intercellular adhesion moluecule-1 (ICAM)-1/leukocyte function-associated antigen-1 (LFA-1) monoclonal antibodies (mAbs). In the spleen cells of the DP rats that had accepted pancreatic grafts (60 days postgrafting), flow cytometric analysis showed that NKR-P1(+)TCRalphabeta(+) (NKT) cells had proliferated markedly, with the proportion of 12.8 +/- 1.7% in the total splenic T cells, most of which (86.2%) were derived from the donor (RT6.2(+)). By enzyme-linked immunonosorbent assay (ELISA), serum interferon gamma (IFN-gamma) was not detected (<13 pg/ml) in all rats. However, interleukin-4 (IL-4) was detected as 158.8 +/- 28.0 pg/ml in the nonrecurrent DP recipients. These data suggested that to prevent IDDM recurrence in the pancreatic graft, the lymphocytes in the pancreaticoduodenal grafts are necessary. Also, the donor-derived NKT cells might have some immunoregulatory functions with a Th2 deviation.

Animals↗