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41.
Purification and characterization of a 43-kilodalton extracellular serine proteinase from Cryptococcus neoformans 总被引:3,自引:0,他引:3
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An extracellular proteinase was purified from culture filtrates of Cryptococcus neoformans NHPY24 by DEAE ion-exchange chromatography and gelatin affinity column chromatography with azoalbumin as the substrate. The molecular mass of the purified enzyme was 43 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, its pH optimum was 7.0 to 8.0, and maximal activity was obtained at pH 7.5 and 37 degrees C. By isoelectric focusing, the purified enzyme had a pI of 4.77. Enzyme activity was inhibited by serine proteinase inhibitors such as phenylmethylsulfonyl fluoride and diisopropylfluorophosphate. The purified enzyme was thus a serine proteinase. It hydrolyzed natural substrates including hemoglobin, beta-casein, and gamma globulin. 相似文献
42.
Xanthii Fructus (XF) is an herb widely used in medicine for the treatment of a variety of inflammatory pathologies. In this study, using mouse peritoneal macrophages, we have examined whether XF affects nitric oxide (NO), tumor necrosis factor (TNF)-α, and interleukin (IL)-12p40 production induced by interferon (IFN)-γ and lipopolysaccharide (LPS). XF inhibits IFN-γ and LPS-induced NO production in a dose dependent manner. The decrease in NO synthesis was reflected as a decreased amount of inducible NO synthase protein. Furthermore, we also found that XF inhibits pro-inflammatory cytokine TNF-α production. However, treatment of XF in peritoneal macrophages had no effect on IL-12p40 production. These findings suggest that XF may be used in controlling macrophages-mediated inflammatory diseases. 相似文献
43.
Haijo Jung Hee-Joung Kim Sang-Ho Lee Sae-Rome Kim Chang Lyong Ji Jung-Han Kim Sun Kook Yoo Ki-Hwang Kim 《Journal of digital imaging》2004,17(2):100-108
This study evaluated the migration to full-PACS of medical image data archived using mini-PACS at two hospitals of the Yonsei University Medical Center, Seoul, Korea. A major concern in the migration of medical data is to match the image data from the mini-PACS with the hospital OCS (Ordered Communication System). Prior to carrying out the actual migration process, the principles, methods, and anticipated results for the migration with respect to both cost and effectiveness were evaluated. Migration gateway workstations were established and a migration software tool was developed. The actual migration process was performed based on the results of several migration simulations. Our conclusions were that a migration plan should be carefully prepared and tailored to the individual hospital environment because the server system, archive media, network, OCS, and policy for data management may be unique. 相似文献
44.
Implantation of bone marrow mononuclear cells using injectable fibrin matrix enhances neovascularization in infarcted myocardium 总被引:11,自引:0,他引:11
Ryu JH Kim IK Cho SW Cho MC Hwang KK Piao H Piao S Lim SH Hong YS Choi CY Yoo KJ Kim BS 《Biomaterials》2005,26(3):319-326
Neovascularization may improve cardiac function and prevent further scar tissue formation in infarcted myocardium. A number of studies have demonstrated that bone marrow-derived cells have the potential to induce neovascularization in ischemic tissues. In this study, we hypothesized that implantation of bone marrow mononuclear cells (BMMNCs) using injectable fibrin matrix further enhances neovascularization in infarcted myocardium compared to BMMNC implantation without matrix. To test this hypothesis, infarction was induced in rat myocardium by cryoinjury. Three weeks later, rat BMMNCs were mixed with fibrin matrix and injected into the infarcted myocardium. Injection of either BMMNCs or medium alone into infarcted myocardium served as controls. Eight weeks after the treatments, histological analyses indicated that implantation of BMMNCs using fibrin matrix resulted in more extensive tissue regeneration in the infarcted myocardium compared to BMMNC implantation without matrix. Examination with fluorescence microscopy revealed that cells labeled with a fluorescent dye prior to implantation survived in the infarcted myocardium at 8 weeks of implantation. Importantly, implantation of BMMNCs using fibrin matrix resulted in much more extensive neovascularization in infarcted myocardium than BMMNC implantation without matrix. The microvessel density in infarcted myocardium was significantly higher (p < 0.05) when BMMNCs were implanted using fibrin matrix (350 +/- 22 microvessels/mm2) compared to BMMNC implantation without matrix (262 +/- 13 microvessels/mm2) and medium injection (76 +/- 9 microvessels/mm2). In addition, average internal diameter of microvessels was significantly larger (p < 0.05) in BMMNC implantation with fibrin matrix group (14.6 +/- 1.2 microm) than BMMNC implantation without matrix group (10.2 +/- 0.7 microm) and medium injection group (7.3 +/- 0.5 microm). These results suggest that fibrin matrix could serve as a cell implantation matrix that enhances neovascularization efficacy for myocardial infarction treatment. 相似文献
45.
Immunohistochemical analysis of Smac/DIABLO expression in human carcinomas and sarcomas 总被引:27,自引:0,他引:27
Yoo NJ Kim HS Kim SY Park WS Park CH Jeon H Jung ES Lee JY Lee SH 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(3):382-388
Second mitochondria-derived activator of caspases (Smac/DIABLO) is released from mitochondria into the cytosol during apoptosis, promoting caspase activation by neutralizing the inhibition of inhibitor of apoptosis proteins (IAPs) on caspases. Alteration of apoptosis is essential for cancer development, and cancer cell death by radiation and chemotherapy is largely dependent upon apoptosis. In this study, archival tissues of 100 carcinomas and 50 sarcomas from various origins were analyzed by immunohistochemistry for the expression of Smac/DIABLO. Smac/DIABLO immunoreactivity was seen in 62 of 100 (62%) carcinomas, including 42 of 60 stomach carcinomas, 7 of 10 colorectal carcinomas, 4 of 10 lung carcinomas, 7 of 10 ovarian carcinomas, and 2 of 10 prostate carcinomas. Smac/DIABLO is expressed in 11 of 50 (22%) sarcomas, including 2 of 8 malignant schwannomas, 5 of 11 rhabdomyosarcomas, 2 of 7 malignant fibrous histiocytomas, 1 of 6 leiomyosarcomas, 0 of 8 angiosarcomas, 0 of 8 liposarcomas, and 1 of 2 Ewing's sarcomas. These data demonstrated that Smac/DIABLO expression levels vary depending on the individual cancer types. Furthermore, the present study showed that many human cancers do not express Smac/DIABLO, and suggest that lack of Smac/DIABLO expression in the cancer cells may inhibit apoptosis, thereby promoting their survival. 相似文献
46.
H2O2 enhances Ca2+ release from osteoblast internal stores 总被引:3,自引:0,他引:3
The physiological activity of osteoblasts is known to be closely related to increased intracellular Ca2+ activity ([Ca2+]i) in osteoblasts. The cellular regulation of [Ca2+]i in osteoblasts is mediated by Ca2+ movements associated with Ca2+ release from intracellular Ca2+ stores, and transmembrane Ca2+ influx via Na+-Ca2+ exchanger, and Ca2+ ATPase. Reactive oxygen species, such as H2O2, play an important role in the regulation of cellular functions, and act as signaling molecules or toxins in cells. In this study, we investigated the effects of H2O2 on cellular Ca2+ regulation in osteoblasts by measuring intracellular Ca2+ activities using cellular calcium imaging techniques. Osteoblasts were isolated from the femurs and tibias of neonatal rats, and cultured for 7 days. The cultured osteoblasts were loaded with a Ca2+-sensitive fluorescent dye, Fura-2, and fluorescence images were monitored using a cooled CCD camera, and subsequently analyzed using image analyzing software. The results obtained are as follows: (1) The osteoblasts with lower basal Ca2+ activities yielded a transient Ca2+ increase, a Ca2+ spike, while osteoblasts with higher basal Ca2+ activities showed a continuous increase in [Ca2+]i leading to cell death. (2) Ca2+ spikes, generated after removing Na+ from superfusing solutions, were blocked by H2O2 and this was followed by a sustained increase in Ca2+ activity. (3) ATP- induced Ca2+ spikes were inhibited by pretreating with H2O2 and this was followed by a continuous increase of [Ca2+]i. When cells were pretreated with the exogenous nitric oxide (NO) donor S-Nitroso-N-acetylpenicilance (SNAP, 50 microM), treatments of ATP (1 mM) induced a Ca2+ spike-like increase, but [Ca2+]i did not return to the basal level. (4) The expression of inositol- 1,4,5-triphosphate receptor (IP3R) was enhanced by H2O2. Our results suggest that H2O2 modulates intracellular Ca2+ activity in osteoblasts by increasing Ca2+ release from the intracellular Ca2+ stores. 相似文献
47.
This study was undertaken in order to estimate the incidence of leukemia among Koreans. Medical records were studied of patients with diagnoses of either ICD-9 038 (septicemia), or 204-208 (leukemias), or 284 (aplastic anemia), or 289 (other diseases of the blood and blood-forming organs) in the claims sent in by medical care institutions throughout the country to the Korea Medical Insurance Corporation (KMIC) during the period from January 1, 1986 to December 31, 1987. These records were abstracted in order to identify and confirm new cases of leukemia among the beneficiaries of KMIC, which covers about 10% of the whole Korean population. Using these data from the KMIC, the incidence rates of leukemia among Koreans were estimated as of July 1st, 1986 to June 30, 1987. The crude incidence rate of all types of leukemia among Koreans is estimated to be 3.45 (95% CI; 0.77-9.55) and 2.29 (95% CI; 0.28-7.81) per 100,000 in males and females, respectively. The cumulative rate for the age span 0-64 is 0.25% in males and 0.18% in females, and for the age span 0-74, 0.35% in males and 0.23% in females. The adjusted rates for the standard world population are 3.90 and 2.48 per 100,000 in males and females, respectively. The relative frequencies by type are 51.5% for AML, 21.6% for ALL, 20.2% for CML, and only 1.5% for CLL. The incidence patterns of various types of leukemia, of which this is the first report in Korea, are analyzed and presented.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
48.
Engineering of osteochondral tissue with bone marrow mesenchymal progenitor cells in a derivatized hyaluronan-gelatin composite sponge 总被引:11,自引:0,他引:11
The aim of this study was to investigate the potential of a composite matrix, containing esterified hyaluronic acid and gelatin, to facilitate the osteochondral differentiation of culture-expanded, bone marrow-derived mesenchymal progenitor cells. The cell loading characteristics and the effects of the matrix on cell differentiation were examined in vitro and in vivo. Empty and cell-loaded composites were cultivated for up to 28 days in a chemically defined medium with or without transforming growth factor-beta1 (TGF-beta1). A type II collagen-rich extracellular matrix was produced by cells loaded in the matrix and cultured in the presence of TGF-beta1. Empty and cell-loaded matrices were also implanted subcutaneously in immunodeficient mice. Three types of implant were used: empty (group I), cell-loaded matrices (Group II), and cell-loaded matrices cultured for 14 days in vitro in defined medium with TGF-beta1 (group III). No osteochondral differentiation was found in implanted empty matrices; however, the matrix supported osteochondrogenic cell differentiation in the cell-loaded implants. Preculture in vitro in a chondrogenic medium increased the percentage of osteochondral tissue found in the constructs after 3 weeks. These results indicate the potential use of this composite matrix for delivery of bone marrow-derived mesenchymal progenitor cells for the repair of chondral and osseous defects. The results also indicate that this composite matrix is useful for in vitro tissue engineering. 相似文献
49.
Shin HS Johng HM Lee BC Cho SI Soh KS Baik KY Yoo JS Soh KS 《Anatomical record. Part B, New anatomist》2005,284(1):35-40
Threadlike structures on the surfaces of internal organs, which are thought to be part of the Bonghan duct system, were first reported about 40 years ago, but have been largely ignored since then. Recently, they were rediscovered, and in this study we discuss the Feulgen reaction that specifically stains DNA in order to identify these structures on the surface of rabbit livers as part of the Bonghan system. The distribution, shapes, and sizes of their nuclei are found to be similar to those of intravascular threadlike structures. The endothelial nuclei are rod-shaped, 10-20 mum long, and aligned in a broken-line striped fashion. The threadlike structure consists of a bundle of several subducts, which is a characteristic feature of Bonghan ducts and distinguishes them morphologically from lymphatic vessels. In addition, the Feulgen reaction clearly demonstrates that the subducts pass through a corpuscle, which is usually irregular or oval-shaped and is connected to two or several threadlike structures that form a web on the surfaces of organs. Furthermore, spherical granules of about 1 mum in diameter are detected in the subducts. These granules were well stained by using the Feulgen reaction, which implies that they contain DNA. According to previous reports, a granule is a type of microcell and plays an essential role in the physiology and therapeutic effect of the Bonghan system and acupuncture. This role has yet to be elucidated. 相似文献
50.
Kim YS Cheon KA Kim BN Chang SA Yoo HJ Kim JW Cho SC Seo DH Bae MO So YK Noh JS Koh YJ McBurnett K Leventhal B 《Yonsei medical journal》2004,45(1):81-89
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders. 相似文献