A triplet-triplet annihilation-based photon upconversion (TTA-UC) system with a low threshold excitation intensity () in plain water was developed. Water-soluble anionic porphyrin (PdTPPS) and diphenylanthracene (DCDPA) derivatives were used as light absorbers and emitter molecules, respectively, and no additives such as surfactants were required. The phosphorescence emission from PdTPPS under an excitation wavelength of 528 nm was quenched by DCDPA, resulting in triplet energy transfer, whereas fluorescence from DCDPA was observed in a short wavelength region (400-500 nm).
View Article and Find Full Text PDFThe first asymmetric synthesis of a very promising antituberculosis drug candidate, R207910, was achieved by developing two novel catalytic transformations; a catalytic enantioselective proton migration and a catalytic diastereoselective allylation of an intermediate alpha-chiral ketone. Using 2.5 mol % of a Y-catalyst derived from Y(HMDS)(3) and the new chiral ligand 9, 1.
View Article and Find Full Text PDFLysophosphatidic acid (LPA) is a simple phospholipid but has numerous biological effects through a series of G-protein-coupled receptors specific to LPA. In general, LPA is short-lived when applied in vivo, which hinders most pharmacological experiments. In our continuing study to identify stable LPA analogues capable of in vivo applications, we identified here lysophosphatidylmethanol (LPM) as a stable and pan-LPA receptor agonist.
View Article and Find Full Text PDFA chiral polynuclear Gd complex derived from Gd(O(i)Pr)(3) and FujiCAPO (2 or 3) catalytically generated Gd enolates through two distinct methods; transmetalation from enol silyl ethers and conjugate addition of cyanide to alpha,beta-unsaturated N-acyl pyrroles. These chiral enolates can be enantioselectively protonated by a proton in an asymmetric environment in the polynuclear catalyst. Thus, catalytic enantioselective protonation of enol silyl ethers was promoted by the Gd catalyst (5-10 mol %) in the presence of a stoichiometric amount of 2,6-dimethylphenol.
View Article and Find Full Text PDFIn polytocous animals, blastocysts are evenly distributed along each uterine horn and implant. The molecular mechanisms underlying these precise events remain elusive. We recently showed that lysophosphatidic acid (LPA) has critical roles in the establishment of early pregnancy by affecting embryo spacing and subsequent implantation through its receptor, LPA3.
View Article and Find Full Text PDFA general method for direct alkynylation of trifluoromethyl ketones was developed by using CuO(t)Bu-xantphos or phenanthroline complexes as catalysts. The ligands significantly enhanced the catalyst activity. In addition, KOTf, generated in the catalyst preparation step, exhibited some acceleration effects.
View Article and Find Full Text PDFThe elucidation of specific functions of protein kinase C (PKC) subtypes in physiological processes is an important challenge for the future development of new drug targets. Subtype-selective PKC agonists and antagonists are useful biological tools for this purpose. Most of the currently used PKC modulators elicit their activities through binding to the ATP binding site of PKC, which shares many features with other kinases.
View Article and Find Full Text PDFCatalytic asymmetric synthesis of the natural antibiotic fostriecin (CI-920) and its analogue 8-epi-fostriecin and evaluation of their biological activity are described. We used four catalytic asymmetric reactions to construct all of the chiral centers of fostriecin and 8-epi-fostriecin; cyanosilylation of a ketone, Yamamoto allylation, direct aldol reaction, and Noyori reduction, two of which were developed by our group. Catalytic enantioselective cyanosilylation of ketone 13 produced the chiral tetrasubstituted carbon at C-8.
View Article and Find Full Text PDFThe expression of 15 kinds of lectin-binding carbohydrates was examined histochemically in lung adenocarcinoma. The relation between expression of lectin binding carbohydrates and clinicopathologic factors was studied. The expression of peanut agglutinin (PNA) binding carbohydrates showed a high lymph node metastatic rate.
View Article and Find Full Text PDFCarbohydrate expression of cancer cells is closely related to the metastatic nature of colorectal cancer. In the present study we investigated the relevance of carbohydrate expression profiles of colorectal cancer cells in the primary lesion to metastatic distribution patterns as well as prognosis in 134 cases. Carbohydrate expression was estimated by histochemistry with 17 kinds of lectins and 3 kinds of Lewis-related monoclonal antibodies (MAbs), and correlations between the staining and clinicopathological parameters were examined.
View Article and Find Full Text PDFJ Hepatobiliary Pancreat Surg
December 2001
Ischemia reperfusion (I-R) of the liver induces various events leading to cell death (apoptosis) and subsequent cells proliferation. Recent experimental studies have described the protective effect of ischemic preconditioning (IPC) on I-R injury of the liver. However, the mechanisms involved in this protection remain unknown.
View Article and Find Full Text PDFJ Hepatobiliary Pancreat Surg
October 2001
The protein products of immediate early genes (IEGs) behave as transcriptional regulators and play an important role in the regulation of gene expression associated with liver cell proliferation and apoptosis. The aim of this study was to examine whether the transcription of IEGs was induced by obstructive jaundice during liver regeneration after 70% partial hepatectomy, and to examine their association with animal survival, cell proliferation, and apoptosis. Obstructive jaundice (OJ) was induced in rats by common bile duct ligation (CBDL), and 70% partial hepatectomy was performed 5 days after CBDL (OJ group).
View Article and Find Full Text PDFThis study was conducted to examine the lymph node metastasis-related carbohydrate epitopes of cancer cells in primary lesions of gastric cancer with submucosal invasion (sm gastric cancer). A total of 118 formalin-fixed and paraffin-embedded surgical specimens were studied. Carbohydrate epitopes were detected histochemically using 17 kinds of biotin-labeled lectins and three kinds of monoclonal antibodies (mAbs) against Thomsen-Friedenreich antigen (HB-T1), Tn (HB-Tn1), and sialyl Tn antigens (HB-STn1).
View Article and Find Full Text PDFFukushima J Med Sci
June 1998
We attempted to construct the contour of recurrence in primary lung adenocarcinoma with clinicopathologic variables based on data of 131 patients with completely resected primary lung adenocarcinoma. In univariate analysis, tumor size (more or less 3 cm in diameter), p-T, p-N, pathological stage, differentiation, ly factor and v factor were chosen for prognostic predictors. In multivariate analysis, v factor and p-N were independent variables of local recurrence and metastatic recurrence, respectively.
View Article and Find Full Text PDFSialyl-Tn antigen (STn) expression was studied immunohistochemically in 211 primary advanced gastric carcinomas. The overall rate of positive STn staining was 17% (35/211), and positive STn staining was found not to be correlated with tumor size, depth of invasion, lymph node metastasis, liver metastasis, or peritoneal metastasis. However, patients with tumors that were immunoreactive for STn demonstrated significantly lower survival (P < 0.
View Article and Find Full Text PDFThe aim of this study was to investigate the expression of the immediate early genes (IEGs), c-fos and c-jun, in the rat kidney and liver in two types of hemorrhage shock/resuscitation models. In the first group, hemorrhagic shock was induced by the withdrawal of blood through the carotid artery. A mean arterial blood pressure (MAP) of 40mmHg was maintained for 1h before blood was reperfused.
View Article and Find Full Text PDFWhether hemoglobin (Hb) encapsulated liposomes have vasoconstrictive activity remains controversial. We therefore examined the vascular activity of a liposome Hb, Neo red cell (NRC), in a simple in vitro model of Langendorff perfusion of the rat heart using Krebs-Henseleit (KH) solution as the perfusate. In the KH solution, NRC (Hb at 1 mg/ml), however, induced an immediate and abnormal increase in perfusion pressure.
View Article and Find Full Text PDFBackground: It is believed that EDTA-dependent panagglutination is associated with free carboxylic acids that support reactions of rare autoagglutinins.
Case Report: An ABO typing discrepancy occurred in an 88-year-old patient. The specificity of his autoagglutinin was demonstrated by panel cell study and absorption tests using normal donors' red cells or immunoadsorbents coated with A, B, or O substances.
Artif Cells Blood Substit Immobil Biotechnol
July 1997
We induced shock by exsanguination and administered Neo Red Cells (NRC) after 30 minutes to experimentally examine the efficacy of NRC on severe shock with respect to hemodynamics and oxygen transport capacity. Seven beagles were used for this experiment. After intravenous anesthesia, intratracheal intubation was performed, and inhalation of 50% oxygen was administered.
View Article and Find Full Text PDFTo predict a fetus at risk for neonatal alloimmune thrombocytopenia (NATP) caused by human platelet antigen (HPA)-4 incompatibility, we applied a sequence-specific polymerase chain reaction (PCR-SSP). We were able to determine the HPA-4 genotype of three infants at risk using amniotic fluid cells without the need for fetal blood sampling. The HPA-4 genotypes of amniotic fluid cells determined in this way were completely concordant with the genotype and phenotype of infants' venous blood samples obtained after delivery.
View Article and Find Full Text PDFA 55-year-old male with multiple endocrine neoplasia syndrome accompanied by hyperparathyroidism and hypergastrinemia was admitted because of local recurrence of thymic carcinoid tumor and a parathyroid adenoma. The recurrent thymic carcinoid tumor replaced anterior mediastinum, invaded brachiocephalic vein and superior vena cava, a disseminated nodule was found at pericardium. After induction chemotherapy using carboplatin and etoposide the operation was performed.
View Article and Find Full Text PDFSoybean agglutinin (SBA)-binding carbohydrate expression was studied immunohistochemically in 353 primary gastric carcinomas. The overall rate of positive SBA staining was 23% (81/353), and positive SBA staining was significantly correlated with tumor size, macroscopic tumor type, depth of invasion, lymph node metastasis, and venous invasion (P < 0.05).
View Article and Find Full Text PDFWe describe herein the results of performing a new technique of low anterior resection of the rectum using a PDS endoloop, on ten patients with rectal cancer. This technique involves first preparing the rectosigmoid colon with an anvil as in the conventional low anterior resection; then, after the stapler is inserted transanally, two endoloops are solid over the colon and rectum. The rectum is ligated by pushing the knot of the endoloop and a second knot is applied 2 cm proximal to the first.
View Article and Find Full Text PDFOperation of esophageal cancer accompanies a big surgical stress and postoperative pulmonary complications such as respiratory failure are observed at high frequencies. On the other hand, when a big stress is added to a body, a state of hypercoagulation in which blood coagulation mechanism is abnormally enhanced appears and this state is closely related to organ failures but has many unknown points. So, we examined 39 patients given excision of esophageal cancer with respect to occurrence of postoperative respiratory failures, participation of coagulopathy in aggravation and their degrees before and after the operation to find out the relationship between postoperative respiratory failure and the state of hypercoagulation.
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