Glycoconjugates are an important class of biomolecules that regulate numerous biological events in cells. However, these complex, medium-size molecules are metabolically unstable, which hampers detailed investigations of their functions as well as their potential application as pharmaceuticals. Here we report sialidase-resistant analogues of ganglioside GM3 containing a monofluoromethylene linkage instead of the native -sialoside linkage.
View Article and Find Full Text PDFBackground: The relationship between infarct dimensions and neurologic severity in patients with acute pontine infarctions remains unclear. This study aimed to clarify the morphometric predictive value of magnetic resonance imaging for motor deficits in pontine infarction.
Methods: Nineteen patients with an acute pontine infarction (12 males and 7 females, 70.
RE derivatives, which are cell-permeable and non-electrophilic dual-specificity protein phosphatase inhibitors developed in our laboratory, inhibit CDC25A/B non-competitively, as determined by means of kinetic experiments. To identify the binding site of RE derivatives, we designed and synthesized the new probe molecule RE142, having a Michael acceptor functionality for covalent bond formation with the enzyme, a biotin tag to enable enrichment of probe-bound peptide(s), and a chemically cleavable linker to facilitate release of probe-bound peptides from avidin beads. LC-MS analysis indicated that RE142 binds to one of the residues Cys384-Tyr386 of CDC25A, within a pocket adjacent to the catalytic site.
View Article and Find Full Text PDFThe Spontaneously Diabetic Torii (SDT) rat is a new model for non-obese type 2 diabetes. In the present study, we investigated changes in insulin secretion from the pancreas of male SDT rats aged 8, 16, and 24 weeks in order to analyze pancreatic function. An analysis of glucose-stimulated insulin secretion (GSIS) in isolated islets showed a marked reduction in insulin secretion in pre-diabetic 16-week-old SDT rats.
View Article and Find Full Text PDFThis paper examines the present and potential role of effluent trading in water quality management. In particular, it focuses upon the case of the Chesapeake Bay on the east coast of the US, where the implementation of a trading system has been discussed and undertaken. Potential benefits of effluent trading include advantages such as the following: (1) With appropriate monitoring and enforcement, the total pollutant loadings can be kept at or below the prespecified level.
View Article and Find Full Text PDFThirty-three sudden infant death syndrome (SIDS)-related civil and criminal lawsuits in Japan were retrieved from judicial precedent databases "Hanrei Masutar (Judicial Decisions Master)" and "Hanrei Taikei (Judicial Decisions System) using "SIDS" as a keyword. Sleeping posture and developmental stage of occurrence were studied in each of the cases retrieved, whether or not a legal autopsy had been performed. The influence exerted on court decisions by Japanese definitions of SIDS as well as the relationship between causes of death and court decisions were studied.
View Article and Find Full Text PDFDual-space, single-contrast arthrotomolgraphy of the TMJ was performed on a 19-year-old woman with a history of pain and clicking. Simultaneous multi-layer arthrotomography with computed radiography was used for the present examination. Anterior disc displacement with reduction was observed in the sagittal plane, together with a double line in the lower joint space.
View Article and Find Full Text PDFRoutine screening of compounds for inhibition of ADP-induced platelet aggregation in vitro revealed that 1,1'-hexamethylenebis[3-cyclohexyl-3-[(cyclohexylimino) (4-morpholinyl) methyl]urea] (1) was active and represented the first example of a bis(acylguanidine) with possible antithrombotic activity. In order to develop a structure-activity relationship for this class of compounds, we synthesized a number of new bis(acylguanidines). These were tested in vitro, and several analogues were also active.
View Article and Find Full Text PDFForty-three cases of primary pontine hemorrhage were seen in our hospital from 1979 to 1986. We studied the correlations between clinical signs, CT, ABR findings and their outcomes, and then reported surgical results. The case consisted of 30 males and 13 females between 32 to 73 years with an average age of 54.
View Article and Find Full Text PDFSafety, tolerance, and pharmacology of 9-beta-methylcarbacyclin calcium (ciprostene calcium) was investigated in healthy male volunteers. This stable prostacyclin analogue was infused intravenously into groups of 12, 11, and three volunteers for three, six, and eight hours, respectively, in doses up to 480 ng/kg/min. Based on the tolerance data obtained, a single-blind, placebo-controlled study was conducted.
View Article and Find Full Text PDFRoutine screening of compounds for inhibition of collagen-induced platelet aggregation in vitro revealed 4,5-bis-(4-methoxyphenyl)-1,2,3-thiadiazole (2) was active and it represents the first example of a 1,2,3-thiadiazole with possible antithrombotic activity. In order to develop a structure-activity relationship for this heterocycle, a number of new 4(5)-mono- and -disubstituted 1,2,3-thiadiazoles were synthesized. These were tested in our screen and a number of additional active compounds were found.
View Article and Find Full Text PDFWhen thrombin, tissue thromboplastin or Russell's viper venom was added to a suspension of either lymphocytes or neutrophils containing normal plasma, aggregation of these cells ensued. The aggregate formed one gelatinous mass which was readily separable from the cell free supernatant, an aliquot of which caused platelet aggregation. This leukocyte derived platelet aggregatory substance had characteristics similar to thrombin but not AGEPC.
View Article and Find Full Text PDFSeveral prostaglandin D (PGD) analogues have been synthesized, incorporating the following variations: (a) varying degrees of side-chain unsaturation, (b) C-9 hydroxy removed or in the unnatural 9 beta configuration, (c) metabolically stabilized analogues (e.g., 15-methyl, 16,16-dimethyl, 17-phenyl, etc.
View Article and Find Full Text PDFPlatelet aggregation was measured in rat and human platelet-rich plasma (PRP) after the addition of various amounts of arachidonic acid (AA), prostaglandin H2 (PGH2), adenosine diphosphate (ADP), or collagen. AA but not PGH2 caused rat platelets to aggregate in citrated or heparinized PRP. Both AA and PGH2 produced significant amounts of thromboxane A2 (TxA2) measured as thromboxane B2 (TxB2).
View Article and Find Full Text PDFA thiazole derivative, 4,5-bis(p-methoxyphenyl)-2-(trifluoromethyl)-thiazole was found to be a potent inhibitor of collagen-induced platelet aggregation, in vitro, using platelets from at at least six species, including man. It was active in human platelet-rich plasma at a concentration of 1 ng/ml. While its antiplatelet activity was greater than that of flurbiprofen, its cyclooxygenase activity was equivalent to that of flurbiprofen.
View Article and Find Full Text PDFIn our continuing effort to discover compound which inhibit collagen-induced platelet aggregation, we have screened compounds in a mouse pulmonary thromboembolism screen. Methyl 4,5-bis(4-methoxyphenyl)-2-thiazoleacetate (3) was very active in the above screen. However, 3 was active for less than 5 min when given orally to guinea pigs.
View Article and Find Full Text PDFThe prostanoid 3-oxa-4,5,6-trinor-3,7-inter-m-phenylene PGE1 (OI-PGE1) has been shown to be a more potent inhibitor of ADP-induced human platelet aggregation than PGE1. OI-PGE1 inhibits ex vivo ADP-induced platelet aggregation for 60 minutes after an oral dose of 20 mg/kg to rats. Present studies compare duration of ex vivo inhibition of ADP-induced platelet aggregation in the rat by OI-PGE1, its methyl ester and amide after administration by various routes.
View Article and Find Full Text PDFThe prostanoid 3-oxa-4,5,6-trinor-3,7-inter-m-phenylene-PGE1-amide (OI-PGE1-amide) has a prolonged duration of oral platelet aggregation inhibitory activity when compared to the parent free acid (OI-PGE1) in the rat. When incubated in rat plasma at 1 microgram/ml for 30 seconds prior to addition of ADP, OI-PGE1-amide inhibits in vitro rat platelet aggregation approximately 50%. OI-PGE1 inhibits at 1 ng/ml.
View Article and Find Full Text PDFBull Environ Contam Toxicol
October 1979
2-(4'-Isobutylphenyl)propionic acid, ibuprofen, is an antiinflammatory agent which possesses moderate platelet aggregation inhibitory activity. It was therefore of interest to determine what effect the replacement of the phenyl group of ibuprofen by a 3-pyridyl ring would have on platelet aggregation inhibitory activity. As a result, 6-isobutyl-alpha-methyl-o-pyridineacetic acid (7) and its 2-chloro analogue 13 were synthesized.
View Article and Find Full Text PDFThe effects of lysolecithin (LPC) on aggregation, serotonin release, shape, and lysis of rabbit, pig, or human platelets in platelet-rich plasma (PRP) or Tyrode albumin solution were examined during prolonged incubation. LPC added to citrated or heparinized PRP from humans or rabbits at a final concentration above 100 muM caused instantaneous inhibition of platelet aggregation induced by adenosine diphosphate (ADP), epinephrine (human PRP only), collagen, or thrombin. The inhibitory effect of LPC was found to be partially reversible over a period of 60-90 min.
View Article and Find Full Text PDFThe synthesis of dl-4,5,6-trinor-3,7-inter-m-phenylene-3-oxaprostaglandins of the E1 and F1alpha series from 6-endo-(1-heptenyl)-bicyclo[3:1:0]hexan-3-one (III), is described. Preliminary biological screening data for gerbil colon smooth muscle stimulation, rat blood pressure and substrate specificity toward 15-hydroxyprostaglandin dehydrogenase is presented. Platelet function studies, both in vitro and in vivo of dl-4,5,6-trinor-3,7-inter-m-phenylene-3-oxa-PGE1, methyl ester (VIII) are presented.
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