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991.
Crossreactive B cells are present during a primary but not secondary response in BALB/c mice expressing a bcl-2 transgene. 总被引:6,自引:0,他引:6
While it is clear that multiple genetic factors lead to autoimmune diseases such as systemic lupus erythematosus (SLE), it appears that an environmental stimulus is also required to trigger the disease in susceptible individuals. We have previously demonstrated that B cells making crossreactive antibodies that bind to both phosphorylcholine (PC), a component of pneumococcal cell wall polysaccharide, and double stranded DNA (dsDNA) can be found in BALB/c mice immunized with PC coupled to a protein carrier. While these B cells are normally eliminated in vivo by apoptosis, they can be recovered ex vivo by fusion with a cell line overexpressing the anti-apoptotic gene bcl-2. This observation led us to ask whether in vivo expression of bcl-2 might abrogate immunologic tolerance during an ongoing immune response. In the present study, we have examined BALB/c mice that constitutively express a bcl-2 transgene in the B cell compartment. Bcl-2 transgenic BALB/c mice have an expanded B cell number, but display no evidence of anti-dsDNA antibodies in the serum even following immunization with PC coupled to a protein carrier. Crossreactive anti-DNA, anti-PC B cells can be recovered by hybridoma technology late in the primary response, but do not appear in the memory B cell compartment. Thus, in vivo expression of bcl-2 can rescue B cell autoreactivity in the primary immune response, but is not sufficient for activation of these B cells or for their maintenance in the memory compartment. 相似文献
992.
Surgical resection is standard treatment for hepatocellular carcinoma but is often not possible in the presence of cirrhosis or poor liver function. We present a method of performing limited hepatectomy in patients with hepatocellular carcinoma and cirrhosis. We call this method laparoscopy-assisted mini-laparotomy (LAML). The site of the tumor is localized by ultrasound through a laparoscope, and a small skin incision is made over that site to facilitate removal of the portion of liver containing the tumor. Eleven patients underwent limited hepatic resection by LAML. The tumors were on the margin of the liver. There was no hospital mortality or serious complications. The average length of hospital stay was 6.4 days. LAML can be safely performed for hepatocellular carcinoma in cirrhotic patients. It decreases operating time, length of hospital stay, and blood loss. 相似文献
993.
994.
Boguniewicz M Abramovits W Paller A Whitaker-Worth DL Prendergast M Cheng JW Wang P Tong KB 《Journal of drugs in dermatology : JDD》2007,6(4):416-423
Atopic dermatitis (AD) increases health care utilization, affects patient quality of life, places a burden on caregivers, decreases patient/parent productivity, and adds to health care costs. Few studies have examined the effect of specific treatment modalities across a variety of AD-related outcomes. This prospective, multicenter, open-label longitudinal study of adult and pediatric patients with moderate to severe AD was conducted to evaluate the effect of a specific therapeutic intervention on AD-related outcomes over a period of 6 months. Surveys collected physician clinical assessments and patient- and caregiver-reported data across the following domains: clinical outcome, health care utilization/costs, quality of life, physical appearance, productivity/absenteeism, and medication compliance. This study is intended to help guide future research efforts on the net costs and benefits of different interventions across a diverse set of domains and in larger populations. 相似文献
995.
Kuo PC Shen YC Yang ML Wang SH Thang TD Dung NX Chiang PC Lee KH Lee EJ Wu TS 《Journal of natural products》2007,70(12):1906-1909
Cytotoxicity-guided phytochemical investigation of a methanolic extract of Croton tonkinensis afforded two new kaurane diterpenoids (1, 2) and 10 known ent-kaurane-type diterpenoids (3- 12). The structures of 1 and 2 were based on analysis of spectroscopic and mass spectral data. Compounds 3- 12 were identified by comparison of their spectroscopic and physical data with those reported in the literature. Selected compounds from this plant were examined for cytotoxic and anti-inflammatory activities. Compounds 4 and 9 showed the highest cytotoxic activity against the tested tumor cell lines. Compounds 3, 4, 6, 8, 9, and 11 had IC 50 values less than 5 microM and were more potent than the nonspecific NOS inhibitor L-NAME in inhibiting LPS-induced NO production. 相似文献
996.
Tyan CC Liang WM Shy HY Kuo HW Lin JG Chen HW Chen JJ 《Acupuncture & electro-therapeutics research》2007,32(1-2):87-96
This study was to provide a standardized definition of the positioning method of finger placement on the radial artery for pulse diagnosis in traditional Chinese medicine (TCM); that is, to define the locations of Cun, Guan and Chi in TCM. A total of 200 subjects (100 males and 100 females, 18-40 years of age) were recruited from the general population. According to ancient TCM records, the "6% of the elbow length" (ELx6%) is used as the standard method of establishing the length of Cun. We hypothesized that the highest point of "prominent bone" (PB) is the lower limit of Cun, so "the distance between the distal wrist crease and the highest point of the PB" (DWP) is considered the length of Cun. If this hypothesis holds, then we can define the locations of Cun, Guan and Chi by using the ratio 6:6:7 from the ancient TCM records. The distribution of relative bias and paired t-test were used to verify the findings. The mean value of relative bias of DWP compared with ELx6% was close to 0% (males = 2.1%, SD = 12.2%; females = 0.2%, SD = 12.6%). The paired t-test confirmed that there was no significant difference (p > 0.05) between the mean values of the DWP and ELx6%. Therefore, it is reasonable to assume that the length of the Cun is equal to the length of the DWP. Our findings confirm that the location of Cun is from the distal wrist crease to the highest point of PB. 相似文献
997.
The role of the VEGF-C/VEGFR-3 axis in cancer progression 总被引:9,自引:0,他引:9
Su JL Yen CJ Chen PS Chuang SE Hong CC Kuo IH Chen HY Hung MC Kuo ML 《British journal of cancer》2007,96(4):541-545
Vascular endothelial growth factor (VEGF) receptor 3 (VEGFR-3) (also called VEGFR-3) is activated by its specific ligand, VEGF-C, which promotes cancer progression. The VEGF-C/VEGFR-3 axis is expressed not only by lymphatic endothelial cells but also by a variety of human tumour cells. Activation of the VEGF-C/VEGFR-3 axis in lymphatic endothelial cells can facilitate metastasis by increasing the formation of lymphatic vessels (lymphangiogenesis) within and around tumours. The VEGF-C/VEGFR-3 axis plays a critical role in leukaemic cell proliferation, survival, and resistance to chemotherapy. Moreover, activation of the VEGF-C/VEGFR-3 axis in several types of solid tumours enhances cancer cell mobility and invasion capabilities, promoting cancer cell metastasis. In this review, we discuss the novel function and molecular mechanism of the VEGF-C/VEGFR-3 axis in cancer progression. 相似文献
998.
Chen YC Lu PH Pan SL Teng CM Kuo SC Lin TP Ho YF Huang YC Guh JH 《Biochemical pharmacology》2007,74(1):10-19
Cancer chemotherapeutic agents that interfere with tubulin/microtubule function are in extensive use. Quinolone is a common structure in alkaloids and its related components exhibit several pharmacological activities. In this study, we have identified the anticancer mechanisms of 2-phenyl-4-quinolone. 2-Phenyl-4-quinolone displayed anti-proliferative effect in several cancer types, including hormone-resistant prostate cancer PC-3, hepatocellular carcinoma Hep3B and HepG2, non-small cell lung cancer A549 and P-glycoprotein-rich breast cancer NCI/ADR-RES cells. The IC(50) values were 0.85, 1.81, 3.32, 0.90 and 1.53 microM, respectively. 2-Phenyl-4-quinolone caused G2/M arrest of the cell-cycle and a subsequent apoptosis. The turbidity assay showed an inhibitory effect on tubulin polymerization. After immunochemical examination, the data demonstrated that the microtubules were arranged irregularly into dipolarity showing prometaphase-like states. Furthermore, 2-Phenyl-4-quinolone induced the Mcl-1 cleavage, the phosphorylation of Bcl-2 and Bcl-xL (12-h treatment), and the caspase activation including caspase-8, -2 and -3 (24-h treatment). The exposure of cells to 2-phenyl-4-quinolone caused Cdk1 activation by several observations, namely (i) elevation of cyclin B1 expression, (ii) dephosphorylation on inhibitory Tyr-15 of Cdk1, and (iii) dephosphorylation on Ser-216 of Cdc25c. Moreover, a long-term treatment (36h) caused the release reaction and subsequent nuclear translocation of AIF. In summary, it is suggested that 2-phenyl-4-quinolone displays anticancer effect through the dysregulation of mitotic spindles and induction of mitotic arrest. Furthermore, participation of cell-cycle regulators, Bcl-2 family of proteins, activation of caspases and release of AIF may mutually cross-regulate the apoptotic signaling cascades induced by 2-phenyl-4-quinolone. 相似文献
999.
Song F Lu S Gunnet J Xu JZ Wines P Proost J Liang Y Baumann C Lenhard J Murray WV Demarest KT Kuo GH 《Journal of medicinal chemistry》2007,50(12):2807-2817
High-throughput screening of a subset of the J&J compound library containing the carboxylic acid functional group uncovered a bromophenyl derivative as a moderate potent GPR40 agonist. Chemical elaboration of this bromophenyl led to the discovery of a novel series of GPR40 agonists with submicromolar potency. Among them, 22 and 24 behaved as full agonists when compared to the endogenous GPR40 ligand linolenic acid in a functional Ca+2 flux assay in HEK cells expressing GPR40 receptor. Several GPR40 agonists have also demonstrated the ability to induce glucose-mediated insulin secretion in the mouse MIN6 pancreatic beta-cell line. Our data supports the hypothesis that GPR40 may play an important role in fatty acid-mediated glucose-dependent insulin secretion. Compound 22 exhibited good pharmacokinetic profile in rat and may serve as a good candidate for in vivo study and may help to determine if GPR40 agonists would be beneficial in the treatment of type II diabetes. 相似文献
1000.
Wen CC Kuo YH Jan JT Liang PH Wang SY Liu HG Lee CK Chang ST Kuo CJ Lee SS Hou CC Hsiao PW Chien SC Shyur LF Yang NS 《Journal of medicinal chemistry》2007,50(17):4087-4095
In this study, 221 phytocompounds were evaluated for activity against anti-severe acute respiratory syndrome associated coronavirus (SARS-CoV) activities using a cell-based assay measuring SARS-CoV-induced cytopathogenic effect on Vero E6 cells. Ten diterpenoids (1-10), two sesquiterpenoids (11 and 12), two triterpenoids (13 and 14), five lignoids (15-19), curcumin (20), and reference controls niclosamide (21) and valinomycin (22) were potent inhibitors at concentrations between 3.3 and 10 microM. The concentrations of the 22 compounds to inhibit 50% of Vero E6 cell proliferation (CC50) and viral replication (EC50) were measured. The selective index values (SI = CC50/EC50) of the most potent compounds 1, 5, 6, 8, 14, and 16 were 58, >510, 111, 193, 180, and >667, respectively. Betulinic acid (13) and savinin (16) were competitive inhibitors of SARS-CoV 3CL protease with Ki values = 8.2 +/- 0.7 and 9.1 +/- 2.4 microM, respectively. Our findings suggest that specific abietane-type diterpenoids and lignoids exhibit strong anti-SARS-CoV effects. 相似文献