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641.
Differential chemokine response of murine macrophages stimulated with cytokines and infected with Listeria monocytogenes 总被引:1,自引:0,他引:1
During inflammatory processes the infected macrophage is a rich source of
chemokines which induce infiltration of leukocytes to the site of
infection. We investigated the regulation of chemokine production by murine
macrophages in response to infection with the intracellular bacterial
pathogen, Listeria monocytogenes. As a source of quiescent macrophages,
murine bone marrow-derived macrophages (BMM) cultured under serum-free
conditions were used. With RT-PCR, we detected induction of RNA message for
the chemokines macrophage inflammatory protein (MIP)-2, KC, MIP-1alpha,
MIP-1beta, IFN-gamma-inducible protein- 10 and RANTES in L.
monocytogenes-infected macrophages. Accordingly, ELISA-detectable
MIP-1alpha, MIP-2 and KC protein was induced by infection with L.
monocytogenes. In contrast, L. monocytogenes infection of BMM alone failed
to induce considerable expression of monocyte chemoattractant protein
(MCP)-1 at the mRNA or protein level, but co-treatment with IFN-gamma was
necessary. Release of infection- triggered MIP-2, MIP-1alpha and KC was
negatively regulated by IFN- gamma. Similarly, IL-4 stimulated MCP-1
release by infected macrophages but reduced production of MIP-1alpha, MIP-2
and KC. IL-10 turned out to be a general deactivator in terms of macrophage
chemokine production. IL-13 had no effect on MIP-1alpha, MIP-2 and KC
production by infected BMM, but slightly reduced MCP-1 release. By using
IFN-gamma and IL-4 gene deletion mutant mice, in vivo regulation of these
chemokines by IL- 4 and IFN-gamma in listeriosis was studied. In summary,
our results show that chemokines are produced by macrophages infected with
L. monocytogenes, and that chemokine release is differentially regulated by
the macrophage modulators IFN-gamma, IL-4, IL-10 and IL-13.
相似文献
642.
Vidal F; Fugger EF; Blanco J; Keyvanfar K; Catala V; Norton M; Hazelrigg WB; Black SH; Levinson G; Egozcue J; Schulman JD 《Human reproduction (Oxford, England)》1998,13(2):308-312
Using fluorescent in-situ hybridization (FISH) we have evaluated, on a
blind basis, the efficiency of flow cytometry to separate human X- and
Y-chromosome bearing spermatozoa. Our data demonstrate that human
spermatozoa can be sorted to a purity of 80-90% for X spermatozoa and of
60-70% for Y spermatozoa. Our results using triple FISH fully agree with
the sorting treatment used in each case and corroborate the efficiency of
the flow sorting technique for sperm sex selection. In these limited
samples (200-500 sperm/donor), the frequencies of disomic or diploid
spermatozoa were not increased when comparing the sorted samples with
unselected samples or with our control series.
相似文献
643.
Immune responses to the expressed products of the CSP antigen gene of Plasmondium falciparum south in China isolate FCC1/HN in Hela cell@Yu XB
@Liu YW
@Luo SH 相似文献
644.
Mahendra Jain Rakhee Kapadia Ravirajsinh N Jadeja Menaka C Thounaojam Ranjitsinh V Devkar SH Mishra 《Asian Pacific Journal of Tropical Biomedicine》2011,1(6):443-447
Objective
To evaluate the cytotoxicity and hepatoprotective potentials of extracts, fractions or isolated compound from the leaves of Feronia limonia (F. limonia).Methods
Qualitative phytochemical analysis of extracts, fractions or compound was performed by means of thin layer chromatography and spectroscopic assays. The % purity of compound was measured by analytical HPLC. Extracts, fractions or compound have been individually evaluated for their cytotoxicity effects (10, 20, 100, 250, 500, 750 and 1 000 µg/mL). Based on the inhibitory concentration (IC50) obtained from the cell viability assay, graded concentrations of extracts, fractions or isolated compound were assessed (10, 20, 50, 100, 200 µg/mL) for its hepatoprotective potential against CCl4-induced hepatotoxicity by monitoring activity levels of serum glutamatic pyruvatic transaminase (SGPT) and serum glutamic oxaloacetic transaminase (SGOT).Results
Results indicated that the methanol extract of F. limonia was non-toxic and hepatoprotective in nature as compared with the petroleum ether extract. The acetone fraction of methanolic extract also showed similar properties but the subsequent two fractions were cytotoxic. However, the pure compound isolated from the penultimate fraction of methanolic extract was non-toxic and hepatoprotective in nature. Biochemical investigations (SGOT, SGPT) further corroborated these cytological observations.Conclusions
It can be concluded from this study that F. limonia methanol extract, some fractions and pure isolated compound herein exhibit hepatoprotective activity. However, cytotoxicity recorded in the penultimate fraction and investigation of structural details of pure compound warrants further study. 相似文献645.
0 引言 冠心病患者冠状动脉 (冠脉 )病变程度与左室功能受损程度是否存在平行关系尚有争议 .有研究提示冠脉病变程度影响左室功能 ,有人却认为冠脉病变程度对左室功能无直接影响 .近年研究证实冠心病患者左室舒张功能损害出现于左室收缩功能损害之前 .为此 ,我们探讨冠脉病变程度及侧支循环的建立对左室舒张功能的影响 .1 对象和方法1.1 对象 1997- 0 1/ 1998- 0 6我院心血管内科作选择性冠脉造影和左室造影 ,符合以下条件者 :1左前降支、左回旋支和右冠脉至少有一支管腔狭窄直经≥ 75 %或左主干狭窄≥5 0 % ;2原发病为冠心病 ;3排除… 相似文献
646.
Stereotactic breast biopsy with a biopsy gun 总被引:36,自引:1,他引:36
Parker SH; Lovin JD; Jobe WE; Luethke JM; Hopper KD; Yakes WF; Burke BJ 《Radiology》1990,176(3):741-747
One hundred three patients underwent stereotactic breast biopsy with an 18-, 16-, or 14-gauge cutting needle and a biopsy gun. After biopsy, a localization wire was placed and surgical biopsy performed. There was agreement of the histologic results in 89 cases (87%) including 14 of 16 cancers (87%) (kappa = 0.806). The gun biopsy yielded the correct diagnosis in four cases involving a lesion (including one cancer) that was missed at the surgical biopsy. Nine cases in which the lesion was missed at gun biopsy can be related to insufficient needle size, the greater difficulty in using one of the two stereotactic devices, and early inexperience with the technique. A 14-gauge needle was used in the last 29 biopsies, the results of which agreed with the surgical pathologic findings in 28 cases (97%). With greater experience, stereotactic-guided large-gauge automated percutaneous biopsy may prove to be an acceptable alternative to surgical biopsy in women with breast masses suspected at mammography. 相似文献
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650.
A 3-yr-old boy presented with a monoarthritis. Persistence of the condition
and some unusual features led to re-evaluation of the original
investigations, when a diagnosis of extensive plexiform neurofibroma
involving his right leg was made. This previously unreported presentation
of neurofibromatosis is discussed.
相似文献