The site-selective acylations of β-hydroxyamides in the presence of other hydroxyl groups are described. Central to the success of this modification is the metal-template-driven acylation using pyridine ketoxime esters as acylating reagents in combination with CuOTf. This strategy enables β-hydroxyl groups to be site-selectively acylated in various derivatives, including sterically hindered secondary β-alcohol.
View Article and Find Full Text PDFSite-selective acylation of α-hydroxyl groups in amides has been achieved in the presence of other primary hydroxyl groups with intrinsic high reactivity. In this methodology, a relatively stable pyridine aldoxime ester was exploited as an acyl donor to suppress undesired acylation. The catalytic activation of a pyridine aldoxime ester with a Lewis acid produced a cationic complex, which preferentially attracted the Lewis basic α-hydroxyamide via a template effect, to thus facilitate o-acylation.
View Article and Find Full Text PDFBackground: Osteopontin (OPN) is a noncollagenous adhesion protein found at the site of atherosclerotic lesions. However, it has not yet been clarified whether or not OPN can promote atherosclerotic lesions. METHODS AND RESULTS We investigated the contribution of OPN to atherosclerosis by evaluating aortic sinus lesions of both OPN transgenic (Tg) and non-Tg mice fed an atherogenic diet (1.
View Article and Find Full Text PDFOsteopontin (OPN) is a soluble secreted phosphoprotein that binds with high affinity to several integrins and it has been found at the site of atherosclerotic lesions. However, the role of OPN expression in vivo is still poorly understood. To investigate the physiological role of OPN in detail, we generated transgenic mice (Tg) overexpressing the OPN gene under control of the cytomegalovirus enhancer/chicken beta-actin promoter.
View Article and Find Full Text PDFJ Card Fail
December 2001
Background: Interleukin (IL)-1 has profound effects on nonimmune cells and organs, including the heart. The effects of IL-1 on transgenic hearts have not yet been described.
Methods And Results: We generated transgenic mice overexpressing the human IL-1 gene under control of the cytomegalovirus enhancer/chicken beta-actin promoter.
Background: Compensatory enlargement (CE) of atherosclerotic human arteries has been reported; however, the pattern of arterial remodeling in response to plaque formation is not unique.
Hypothesis: The study was undertaken to determine the extent of coronary artery compensatory enlargement at stenotic lesions and to correlate the arterial compensatory enlargement with risk factors.
Methods: We studied 62 patients with stable angina and de novo single-vessel disease using intravascular ultrasound and obtained good images in 42 patients (68%).
The aim of this study was to further assess the role of pooled human immunoglobulin (PHIG) on cytokine production from PBMC stimulated with a bacterial superantigen. Human PBMC were cultured with Streptococcus pyrogenic exotoxin A (SPE-A) with or without PHIG and several proinflammatory cytokine levels of culture supernatants were measured. Serum cytokine levels of KD patients before and after PHIG therapy were also examined.
View Article and Find Full Text PDFStreptococcus pyogenes T1 was previously found to produce an acidic mitogenic exotoxin, designated A beta, antigenically distinct from erythrogenic toxin type A (ETA) of strains T1 and NY5. Following chemical analysis and biological characterization, we have renamed this toxin streptococcal mitogenic exotoxin Z (SMEZ). Physicochemical separation of SMEZ from ETA was successfully performed on a hydrophobic chromatograph.
View Article and Find Full Text PDFLarge, bilateral central pulmonary thromboemboli (PTE) led to cor pulmonale and severe hypoxemia in a patient who had undergone Hardy's operation. After several unsuccessful efforts (thrombolysis using a percutaneous catheter and aspiration of the emboli), mechanical clot fragmentation using a percutaneous transluminal angioplasty (PTA) balloon was attempted. This procedure was successful, resulting in a decrease in pulmonary artery pressure from 58/22 (mean 34) mmHg to 20/10 (mean 13) mmHg together with an increase in aortic pressure from 64/36 (mean 45) mmHg to 112/60 (mean 77) mmHg.
View Article and Find Full Text PDFIn vitro glucuronidation of 25-hydroxyvitamin D3 and its pro-form has been investigated by means of HPLC with UV detection. Although both substrates gave 3- and 25-glucuronides in the presence of the rat liver microsomal fraction and uridine-5'-diphosphoglucuronic acid, 25-hydroxyvitamin D3 and its pro-form yielded 3- and 25-glucuronide as the main product, respectively. The latter glucuronide is the one in which the tert-hydroxy group is conjugated.
View Article and Find Full Text PDFAdv Exp Med Biol
December 1997
A solid phase adsorption experiment was performed to detect anti-ETA alpha(NY5 strain ETA) nonneutralizing antibody. Toxin was applied to the Protein A-Sepharose column retaining IgG bound after pretreatment with test serum. Mitogenic activity recovered in the effluent and in the eluate containing the IgG was measured separately in rabbit lymphocyte culture.
View Article and Find Full Text PDFA highly purified streptococcal erythrogenic toxin type-A (SET-A) caused increased vascular permeability, erythema, and leukocyte emigration when injected into the skin of rabbits. A blueing reaction indicating increased vascular permeability appeared at 1 h, reaching the highest intensity between 4 and 5 h, decreasing thereafter and completely disappearing at 12 h after toxin injection. The intensity of the increase in permeability was found to be dose dependent.
View Article and Find Full Text PDFWe describe a new method to measure human serum antibody against streptococcal erythrogenic toxins that uses inhibition of lymphocyte mitogenicity of the toxins as the indicator. Sera from 53% of 53 Kawasaki disease patients contained specific inhibitory activity against A toxin, whereas only 15% had serum inhibitory activity against B toxin. The specific anti-A toxin serum inhibitor was found in 10% of 118 age-matched control patients suffering from various infections and allergic diseases (p = 0.
View Article and Find Full Text PDFStreptococcal erythrogenic toxin type A (ET-A) was purified from culture filtrate of Streptococcus pyogenes strain NY-5 grown in a chemically defined synthetic medium NCTC-135. We succeeded in simplifying the purification procedure, and obtained a highly purified preparation of ET-A. The purification procedure was the combination of ultrafiltration with Amicon PM-10 and YM-10 membranes, chromatofocusing with PBE-94 exchanger (pH 4.
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