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71.
Intratracheal administration of liposomal clodronate accelerates alveolar macrophage reconstitution following fetal liver transplantation 总被引:1,自引:0,他引:1
Everhart MB Han W Parman KS Polosukhin VV Zeng H Sadikot RT Li B Yull FE Christman JW Blackwell TS 《Journal of leukocyte biology》2005,77(2):173-180
To facilitate study of alveolar macrophages in vivo, we developed a method to rapidly and efficiently replace resident alveolar macrophages with macrophages of a different (donor) genotype. Chimeric mice were generated by lethal irradiation followed by fetal liver transplantation (FLT) using green fluorescent protein (GFP) transgenic reporter mice as donors. Kinetics of peripheral blood monocyte (PBM) and alveolar macrophage reconstitution was determined 4 and 10 weeks post-FLT by quantifying the percentage of GFP+ cells. To enhance the recruitment of donor monocytes into the lung after FLT, mice were treated with intratracheal administration of liposomal clodronate to deplete host alveolar macrophages at 6 weeks post-FLT. PBM reconstitution occurred by 4 weeks after FLT (85.7+/-1.6% of CD11b+/Gr-1+ monocytes were GFP+), and minimal alveolar macrophage repopulation was observed (9.5% GFP+). By 10 weeks following FLT, 48% of alveolar macrophages were GFP+ by immunostaining of macrophages on lung tissue sections, and 55.1 +/- 1.6% of lung lavage macrophages were GFP+ by fluorescein-activated cell sorter analysis. Clodronate treatment resulted in a significant increase in GFP+ alveolar macrophages 10 weeks after FLT. By immunostaining, 90% of macrophages were GFP+ on lung tissue sections and 87.5 +/- 1.1% GFP+ in lung lavage (compared with GFP-transgenic controls). The ability of newly recruited alveolar macrophages to clear Pseudomonas aeruginosa and activate nuclear factor-kappaB in response to Eschericia coli lipopolysaccharide demonstrated normal macrophage function. Optimizing this methodology provides an important tool for the study of specific genes and their contribution to alveolar macrophage function in vivo. 相似文献
72.
A mutation in the gene TNFRSF11B encoding osteoprotegerin causes an idiopathic hyperphosphatasia phenotype 总被引:5,自引:0,他引:5
73.
目的研究神经疾病少年儿童患者脆性X综合征(fragjle X syndrome,FraX)的细胞遗传学检测和临床诊治特征。方法应用低叶酸培养基,对患神经疾病的18岁以下146例儿童行X染色体脆性部位的检测,对检出的Frax患儿给以叶酸为主辅以营养神经和神经康复的治疗。结果146例就诊患儿检出FraX13例,检出率为8.90%。以补充叶酸为主的综合治疗取得一定疗效,治疗效果与患儿年龄和原发神经疾病有关。结论FraX值得临床重视,早检出、早治疗收效较好。 相似文献
74.
T M McHugh Y J Wang H O Chong L L Blackwood D P Stites 《Journal of immunological methods》1989,116(2):213-219
A sensitive assay for the simultaneous detection of multiple serum antibodies by flow cytometry was developed. Polystyrene microspheres of 5, 7 and 9.3 micron in diameter were used as solid supports for the attachment of three different antigen preparations from Candida albicans. These antigens were a whole cell extract; a cytoplasmic protein extract and a cell wall polysaccharide. Microsphere-associated fluorescence was quantitated by flow cytometry, with the different sized microspheres analyzed separately using electronic volume gating. This procedure allowed for different antigen-coated microspheres with discrete sizes to be analyzed independently for immunofluorescence. The assay detected antibody levels in human serum at dilutions up to 10(-6) and provided complete discrimination, using all three antigen preparations, between antibody levels seen in healthy subjects and those seen in patients suspected of having a systemic Candida infection. A standard enzyme immunoassay (EIA) failed to provide complete discrimination between healthy subjects and patient samples: at least 17% of patient values fell within the healthy subject range using all three antigen preparations. The microsphere assay which allowed for the simultaneous detection of multiple antibodies, has increased dynamic range over EIA and provides for better discrimination of patients from healthy subjects in comparison to EIA. Precise quantitation of antibodies is possible and the rapid analysis of thousands of microspheres markedly enhances the statistical accuracy of the assay. We suggest this assay is likely to have many other important applications in immunologic testing. 相似文献
75.
The antigen-presenting environment in normal and human papillomavirus (HPV)-related premalignant cervical epithelium 总被引:13,自引:0,他引:13
The activation of HPV-specific T cells within the cervical microenvironment is likely to play an important part in the natural history of cervical intraepithelial neoplasia (CIN). The extent and the type of T cell activation will depend critically on the expression of MHC, costimulatory cell surface molecules and cytokines by keratinocytes and Langerhans cells within the cervical lesion. Expression of MHC class II (HLA-A-DR and -DQ), costimulatory/adhesion molecules (CD11a/18, CD50, CD54, CD58 and CD86) and cytokines (tumour necrosis factor-alpha (TNF-alpha) and IL-10) was therefore investigated by immunohistochemistry in normal squamous epithelium (n = 12), low-grade (n = 23) and high-grade (n = 18) squamous intraepithelial lesions of the cervix. CIN progression was associated with de novo expression of HLA-DR and CD54, and increased expression of CD58 by keratinocytes. However, significantly, there was no expression of any adhesion/costimulation molecule by epithelial Langerhans cells in any cervical biopsy studied. Furthermore, TNF-alpha, a potent activator of Langerhans cells, was expressed constitutively by basal keratinocytes in normal cervix (12+/12). but expression of this cytokine was absent in a number of CIN samples (20+/23 for low-grade, 12+/18 for high-grade CIN). Conversely, the suppressive cytokine IL-10 was absent in normal epithelium (0+/12), but was up-regulated in a number of CIN lesions (12+/23 for low-grade; 8+/18 for high-grade CIN). The restricted expression of costimulation/adhesion molecules and the nature of the cytokine microenvironment within the epithelium may act to limit effective immune responses in some CIN lesions. 相似文献
76.
目的:探讨动态脑电图监测对昏迷病人的应用价值。方法:对107例昏迷患者采用多次动态脑电图监测,分析脑电图改变与临床结局的关系。结果:平坦波型昏迷死亡率较高(94.7%),慢波型昏迷死亡率较低(30.3%),且预后较好。结论:对昏迷病人实施动态脑电图监测,可提高对预后评估及脑死亡的正确判断率。 相似文献
77.
J. -M. Chong Y. Shiozawa Y. Hayashi N. Funata T. Takizawa M. Koike M. Fukayama 《Virchows Archiv : an international journal of pathology》1996,428(4-5):261-266
We report a case of pancreatic acinar cell carcinoma which contained a large number of pleomorphic inclusions with fibrillary internal structures and mature zymogen granules. To clarify the significance of fibrillary inclusions in the differentiation of acinar cells of the pancreas, we further investigated fetal pancreases (gestational weeks 16, 17, 19, 20 and 28). We found two types of inclusions: type A, corresponding to fibrillary inclusion of neoplastic acinar cells, was observed only in a 19-week fetus; type B showed a homogeneous density similar to that of zymogen granules. Type B was observed in all the fetuses after the 17th gestational week. Although the type A inclusion might be generated throught a different mechanism than the type B inclusion, the appearance of a large number of fibrillary inclusions in neoplastic acinar cells may represent a transient form of zymogen granule. 相似文献
78.
目的 :介绍并分析适用于医学动态监测数据的稳健参数估计方法。方法 :结合分布假设和稳健统计给出了参数估计方法。首次提出了一种迭代求取形状参数稳健估计的算法。结果 :该方法对医学动态监测中某种生理量异常所占百分比值统计量的参数估计优于临床普遍采用的方法。结论 :通过对分布拟合、估计优效性和可实现性、估计稳健性等的理论分析和模拟实验表明该方法是一种高效、可靠的稳健参数估计方法 相似文献
79.
Analytical sensitivity, reproducibility of results, and clinical performance of five PCR assays for detecting Chlamydia pneumoniae DNA in peripheral blood mononuclear cells 总被引:7,自引:0,他引:7 下载免费PDF全文
Mahony JB Chong S Coombes BK Smieja M Petrich A 《Journal of clinical microbiology》2000,38(7):2622-2627
Chlamydia pneumoniae has been associated with atherosclerosis and coronary artery disease (CAD), and its DNA has been detected in atheromatous lesions of the aorta, carotid, and coronary arteries by a variety of PCR assays. The objective of this study was to compare the performances of five published PCR assays in the detection of C. pneumoniae in peripheral blood mononuclear cells (PBMCs) from patients with coronary artery disease. The assays included two conventional PCRs, one targeting a cloned PstI fragment and one targeting the 16S rRNA gene; two nested PCRs, one targeting the 16S rRNA gene and one targeting ompA; and a touchdown enzyme time release (TETR) PCR, targeting the 16S rRNA gene. All PCRs had similar analytical sensitivities and detected a minimum of 0.005 inclusion-forming units (IFU) of C. pneumoniae; the ompA nested PCR and the TETR PCR were slightly more sensitive and detected 0.001 IFU. Assay reproducibility was examined by testing 10 replicates of C. pneumoniae DNA by each assay. All five assays showed excellent reproducibility at high levels of DNA, with scores of 10 out of 10 for 0.01 IFU, but exhibited decreased reproducibility for smaller numbers of C. pneumoniae IFU for all tests. Pairwise comparison of test results indicated that there was a significant difference between tests (Cochran Q = 32.0, P<0.001), with the PstI fragment (P<0.001) and 16S rRNA (P = 0.002) assays having lower reproducibility than the nested ompA and TETR assays. To further analyze assay sensitivity, C. pneumoniae-infected U-937 mononuclear cells were added to whole blood, and extracted mononuclear-cell DNA was tested by each assay. All five assays showed similar sensitivities, detecting 15 infected cells; three assays detected 3 infected cells, while all assays were negative at the next dilution (1.5 infected cells). A striking difference in performance of the five assays was seen, however, when PBMCs from CAD patients were tested for C. pneumoniae DNA. The ompA nested PCR detected C. pneumoniae DNA in 11 of 148 (7.4%) specimens, the 16S rRNA nested PCR detected 2 positives among the 148 specimens (1.4%) (P<0.001), and the other 3 assays detected no positive specimens (P<0.001, compared with the ompA assay). These results indicate that analytical sensitivity alone does not predict the ability of an assay to detect C. pneumoniae in whole-blood-derived PBMCs. Before standardized assays can be used in wide-scale epidemiological studies, further characterization of these assays will be required to improve our understanding of their performance in the detection of C. pneumoniae in clinical material. 相似文献
80.
Fertility clinics worldwide routinely produce a large volume of 'waste' follicular aspirate, which is potentially an abundant source of immature ovarian follicles. Current attempts to cultivate these further in vitro to yield viable mature oocytes for fertility treatment have not yet achieved much success. Instead, recent lines of evidence have emerged that are suggestive of a potential stem cell niche within such immature ovarian follicles. The recent discovery of follicular renewal and putative germ-line stem cells within the postnatal mammalian ovary shook the foundations of reproductive biology by challenging the established dogma that mammalian females lose the capacity for germ cell renewal during fetal life, such that a fixed reserve of germ cells (oocytes) enclosed within follicles is endowed at birth. More intriguingly, another recent study in the Drosophila model provided compelling evidence that somatic progenies (nurse cells) of germ-line stem cells had the ability to revert back to the stem-cell-like state. This introduces the exciting possibility that within the mammalian ovarian follicle, similar somatic progenies of germ-line stem cells may also possess a greater intrinsic ability to revert back into functional stem cells. If this is the case, then a favored candidate would be the cumulus/granulosa of immature ovarian follicles, since such cells are true homologues of nurse cells found within the Drosophila ovary. The successful elucidation of a human germ-line stem cell niche within immature ovarian follicles is likely to have huge ramifications in stem cell biology and regenerative medicine. 相似文献