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The effects of the bisbenzylisoquinoline alkaloids tetrandrine and berbamine on the action of IL-1, TNF and PAF were investigated in the rat subcutaneous air pouch model of inflammation. Both compounds were equipotent in the suppression of leukocyte infiltration into air pouches induced by IL-1 and TNF, with ED50 values in the range 20–30 mg/kg/3 days. Both were also equiptent in suppression of PMN infiltration induced by PAF with ED50 values in the same range as that for IL-1 and TNF. However, tetrandrine was more potent than berbamine as a suppressant of PAF-induced MNC infiltration, but much less potent than berbamine in carageenen-induced PMN infiltration. These results suggest that these bisbenzylisoquinolines may have value in the therapy of chronic inflammatory diseases where IL-1, TNF and PAF have a role in pathogenesis. 相似文献
5.
Effect of twenty-three chemotherapeutic agents on the adherence and growth of Giardia lamblia in vitro 总被引:3,自引:0,他引:3
A A Crouch W K Seow Y H Thong 《Transactions of the Royal Society of Tropical Medicine and Hygiene》1986,80(6):893-896
The sensitivity of Giardia lamblia to 23 chemotherapeutic agents was evaluated in vitro with a Growth Inhibition Assay and a recently developed Adherence Inhibition Assay. Of the four established anti-giardia drugs, tinidazole, metronidazole, and furazolidone were found to have strong inhibitory effects on both growth and adherence, while mepacrine had a strong effect on growth only. Three drugs (mefloquine, doxycycline and rifampin) not previously used in giardiasis were found to have significant activity in vitro and may deserve consideration for clinical evaluation of efficacy. Also, the concurrent use of these two in vitro methods provided significant insights into the modes of action of some of these drugs on G. lamblia. 相似文献
6.
一些保肝药物对原代培养大鼠肝细胞糖原合成功能的影响 总被引:1,自引:0,他引:1
本文参照PO Seglen的方法并加以修改,建立了原代培养大鼠肝细胞糖原合成功能的测定体系。观察到联苯双酯既能使正常肝细胞合成糖原增加88%,又能保护肝细胞完全拮抗四氯化碳对其功能的损伤;银耳多糖能使四氯化碳对肝细胞糖原合成功能的损伤减轻57%;去甲斑蝥素10μg/ml能增加肝细胞糖原合成,浓度增加到100μg/ml时,此作用减弱,1000μg/ml则明显抑制糖原的合成,而且在10~100μg/ml浓度时,即能加强四氯化碳的损伤作用;100μg/ml CL1500和熊果酸二钠单独应用可增加肝细胞糖原合成,但与四氯化碳同时应用,反而加重对糖原合成的抑制作用。 相似文献
7.
Identification of cathepsin C mutations in ethnically diverse papillon-Lefèvre syndrome patients 下载免费PDF全文
Hart PS Zhang Y Firatli E Uygur C Lotfazar M Michalec MD Marks JJ Lu X Coates BJ Seow WK Marshall R Williams D Reed JB Wright JT Hart TC 《Journal of medical genetics》2000,37(12):927-932
INTRODUCTION—Papillon-Lefèvre syndrome (PLS) is an autosomal recessive disorder characterised by palmoplantar keratoderma and severe, early onset periodontitis, which results from deficiency of cathepsin C activity secondary to mutations in the cathepsin C gene. To date, 13 different cathepsin C mutations have been reported in PLS patients, all of which are homozygous for a given mutation, reflecting consanguinity.
AIM—To evaluate the generality of cathepsin C mutations in PLS, we studied an ethnically diverse group of 20 unrelated families.
METHODS—Mutations were identified by direct automated sequencing of genomic DNA amplified for exonic regions and associated splice site junctions of the cathepsin C gene. Long range PCR was performed to determine the genomic structure of the cathepsin C gene.
RESULTS—The cathepsin C gene spans over 46 kb, with six introns ranging in size from 1.6 to 22.4 kb. Eleven novel mutations and four previously reported mutations were identified in affected subjects from 14 families. Missense mutations were most common (9/15), followed by nonsense mutations (3/15), insertions (2/15), and deletions (1/15). Among these 14 probands, two were compound heterozygotes. Affected subjects with transgressions of the dermal lesions onto the knees or elbows or both had mutations in both the pro- and mature regions of the enzyme, although most were in the mature region.
CONCLUSION—Mutations in the mature region of cathepsin C were more likely to be associated with the transgressions of the dermatological lesions, although the results were not statistically significant. A comprehensive list of all cathepsin C mutations described to date, representing 25 mutations from 32 families with PLS and related conditions, is also presented.
Keywords: cathepsin C; genetics; severe early onset periodontitis; hyperkeratosis 相似文献
AIM—To evaluate the generality of cathepsin C mutations in PLS, we studied an ethnically diverse group of 20 unrelated families.
METHODS—Mutations were identified by direct automated sequencing of genomic DNA amplified for exonic regions and associated splice site junctions of the cathepsin C gene. Long range PCR was performed to determine the genomic structure of the cathepsin C gene.
RESULTS—The cathepsin C gene spans over 46 kb, with six introns ranging in size from 1.6 to 22.4 kb. Eleven novel mutations and four previously reported mutations were identified in affected subjects from 14 families. Missense mutations were most common (9/15), followed by nonsense mutations (3/15), insertions (2/15), and deletions (1/15). Among these 14 probands, two were compound heterozygotes. Affected subjects with transgressions of the dermal lesions onto the knees or elbows or both had mutations in both the pro- and mature regions of the enzyme, although most were in the mature region.
CONCLUSION—Mutations in the mature region of cathepsin C were more likely to be associated with the transgressions of the dermatological lesions, although the results were not statistically significant. A comprehensive list of all cathepsin C mutations described to date, representing 25 mutations from 32 families with PLS and related conditions, is also presented.
Keywords: cathepsin C; genetics; severe early onset periodontitis; hyperkeratosis 相似文献
8.
Geok Hun Tan Khatijah Yusoff Heng Fong Seow Wen Siang Tan 《Journal of clinical virology》2007,38(1):49-56
BACKGROUND: Phage display is an alternative method for constructing and selecting antibodies with desired specificity towards an antigen. OBJECTIVES: To construct a library of single chain variable fragment (ScFv) towards hepatitis B core antigen (HBcAg). To isolate a ScFv phage clone that interacts with HBcAg and to develop a phage-ELISA for detecting the antigen. STUDY DESIGN: Mice were inoculated with HBcAg and RNA was extracted from their spleen cells. The genes encoding heavy (V(H)) and light (V(L)) chains were amplified, linked via PCR and cloned into a phagemid vector. Phage particles displaying ScFv were panned against HBcAg and a selected clone was characterized and employed as a diagnostic reagent for detecting HBcAg in serum samples. RESULTS: A phage clone that interacts with HBcAg was selected from the antibody library. The binding of the phage to HBcAg was inhibited by a cyclic peptide bearing the WSFFSNI sequence. A phage-ELISA was established using the recombinant phage and as low as 10ng of HBcAg can be detected by the assay. CONCLUSION: The ScFv displayed on the surface of filamentous phage is an alternative choice for diagnosis of HBcAg in serum samples. 相似文献
9.
W K Seow Y H Thong J G McCormack A Ferrante 《International archives of allergy and applied immunology》1988,85(1):63-68
Human neutrophil adherence was enhanced by recombinant human tumour necrosis factor-beta (TNF beta) but suppressed by recombinant human interleukin-2 (IL-2). The opposite effects of these two lymphokines were observed over a range of concentrations consistent with their other biological activities, occurred within 15 min of incubation, and were still evident after 60 min. Pretreatment of neutrophils with both IL-2 and TNF beta resulted in adherence values intermediate between the values obtained with the individual lymphokines. IL-2 suppressed the stimulatory effects of both the chemotactic peptide formyl-methionyl-leucyl-phenyl-alanine (FMLP) and the phorbol ester phorbol myristate acetate (PMA). The combination of TNF beta with either FMLP or PMA produced enhancement of neutrophil adherence which exceeded that of either agent alone. These effects of the lymphokines were not due to endotoxin contamination since their effects were sensitive to heating and insensitive to polymyxin B treatment. These experiments provide further evidence for the critical role of these lymphokines in the regulation of acute and chronic inflammatory processes. 相似文献
10.
Neulen J; Raczek S; Pogorzelski M; Grunwald K; Yeo TK; Dvorak HF; Weich HA; Breckwoldt M 《Molecular human reproduction》1998,4(3):203-206
Vascularization is a prominent event during corpus luteum formation,
providing low density lipoproteins for steroid biosynthesis and enabling
transport of secreted steroids. The process of vascularization is
controlled by specific regulators. Vascular endothelial growth factor
(VEGF), otherwise named vascular permeability factor (VPF), induces
endothelial cell proliferation as well as angiogenesis in vivo and
increases capillary permeability. Here we report the expression of VEGF/VPF
mRNA by cultured human luteinized granulosa cells (GC) for at least 10
days. Without HCG VEGF/VPF expression declined after day 4 and by day 10
was reduced to approximately 30% of the value at day 4. However, after
culture in the presence of 1 U/ml human chorionic gonadotrophin (HCG),
expression of VEGF/VPF mRNA by GC was four times greater than control
experiments by day 10, and increased 100% from day 4 to day 10.
Simultaneously, HCG supplementation increased VEGF/VPF secretion by GC.
Medium VEGF/VPF on day 3 was 13 pM without and 11 pM with HCG. Medium
VEGF/VPF on day 10 was 6 pM without HCG and 29 pM with HCG. These results
suggest that vascularization of the corpus luteum is induced by
HCG-mediated effects of VEGF/VPF.
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