This paper deals with chiral enzymatic resolution of 4-arylthio-2-butanols by lipase to prepare potential intermediates of $\beta$-lactam antibiotics. Among several lipases employed, lipase P type ...enzyme gave the highest ee value to prepare (R)-4-arylthio-2-butyl acetate. The enzymatic resolution of phenyl substituted alcohol (6a) using lipase P showed the highest ee value (99.7%) among those of 4-arylthio-2-butanol derivatives. Lipase P mediated hydrolysis of acylester 7a gave also (R)-alcohol 6a selectively. For determination of enantiomeric purity of these enzymatic resolved analytes, liquid chromatographic analysis was performed using two coupled Chiralcel OD and (R,R)-WhelkO chiral column.
The purpose of CEDA (certified electronic document authority) is to guarantee reliability and stability of electronic documents. When using storage and issuance services which are one of core ...services offered by CEDA, users register their electronic documents and they are issued to a third party later on. In this process, issuance of partial information (part page) instead of the entire registered information prevents unnecessary leakage of information and improves readability of documents. A method which minimizes information leakage upon loss of encryption and decryption keys was proposed.
Fms-like tyrosine kinase 3 internal tandem duplication (FLT3 ITD) mutation is related to poor prognosis in normal-karyotype acute myeloid leukemia (AML). However, the prognostic significance of the ...mutation at relapse has not been adequately investigated. We investigated the prognostic significance of the FLT3 ITD mutation at relapse in normal-karyotype AML patients.
We analyzed 69 normal-karyotype AML patients, in whom paired bone marrow samples taken at initial diagnosis and subsequent relapse were analyzed for the FLT3 ITD mutation at the Asan Medical Center between 1995 and 2009.
Forty patients showed a persistent wild-type genotype, 11 showed the FLT3 ITD mutation at diagnosis and relapse, and 9 lost and another 9 acquired the mutation at relapse. The mutation status at relapse affected the overall survival (OS), with the mutation group showing shorter OS and survival after relapse than the wild-type group did (P<0.001 and P<0.001, respectively), despite having received more frequent stem cell transplantation after relapse than the wild-type group did. However, no difference was detected in the OS and survival after relapse with regard to the mutation status at diagnosis.
The patients with FLT3 ITD mutation at relapse showed poorer prognoses than those without the mutation. However, mutation status at diagnosis did not affect the outcome. These results suggest that, in normal-karyotype AML patients with relapse, the prognostic significance of FLT3 ITD mutation at relapse is greater than that of the mutation status at diagnosis.
Stomach cancer is prevalent in Korea. The purpose of this study was to evaluate the characteristics of superficial gastric cancers detected at SOK Sokpeynhan Internal Medical Network, the nationwide ...primary health care institutions.
We prospectively analysed the clinicopathologic and endoscopic characteristics of 218 superficial gastric cancer patients diagnosed using gastric endoscopy at SOK network from January 2011 through December 2011.
The mean age was 58.5 years old and male to female ratio was 1.7 : 1. Asymptomatic patients were most common (45.0%). The macroscopic classification revealed that simple types (63.8%) were more common than complex types (36.2%). The most common type was IIc (28.4%) and other types were as follows; IIb (16.1%), IIb+IIc (13.3%), IIa (10.6%), III (9.2%), IIa+IIc (7.3%), IIc+IIa (6.0%), IIc+IIb (5.0%). The most commonly involved sites were the body (53.1%) and greater curvature (32.6%) of the stomach. The size of lesion was less than 1 cm (69.3%) and less than 5 mm (33.5%) in diameter. The most common pathologic type was tubular adenocarcinoma (75.7%). Helicobacter pylori infection rate was 50.2%. Fifty five percent of the cases were diagnosed via endoscopy of National Health Insurance Corporation screenings.
Superficial gastric cancers in 2011 at primary health care SOK network were different from those of previous reports. Type IIc was most common but type IIb was more prevalent and the body and greater curvature of the stomach were the most commonly involved sites. Therefore, careful observation of the proximal gastric mucosa and mucosal color change is needed.
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