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141.
Shi M Yu DH Chen Y Zhao CY Zhang J Liu QH Ni CR Zhu MH 《World journal of gastroenterology : WJG》2012,18(8):840-846
AIM: To examine fibroblast activation protein (FAP) expression in pancreatic ductal adenocarcinoma (PDAC) and to analyze its relationship with the clinicopathology of PDAC.METHODS: FAP expression was examined in 134 PDAC specimens by immunohistochemistry, and in four pancreatic cancer cell lines (SW1990, Miapaca-2, AsPC-1 and BxPC-3) by Western blotting assay. We also analyzed the association between FAP expression in PDAC cells and the clinicopathology of PDAC patients.RESULTS: The results showed that the FAP was ex-pressed in both stromal fibroblast cells (98/134, 73.1%) and carcinoma cells (102/134, 76.1%). All 4 pancreatic cancer cell lines expressed FAP protein at different levels. Protein bands corresponding to the proteolytically active 170-kDa seprase dimer and its 88-kDa seprase subunit were identified. Higher FAP expression in carcinoma cells was associated with tumor size (P < 0.001), fibrotic focus (P = 0.003), perineural invasion (P = 0.009) and worse clinical outcome (P = 0.0085).CONCLUSION: FAP is highly expressed in carcinoma cells and fibroblasts in PDAC tissues, and its expression is associated with desmoplasia and worse prognosis. 相似文献
142.
目的制备具有防治增生性瘢痕(HS)作用的载丹酚酸B的穿膜肽TAT修饰脂质体(SAB-TAT-LIP),建立其质量评价方法,并初步考察其对体外人皮肤成纤维(HSF)细胞增殖和迁移的影响。方法采用pH梯度逆向蒸发法制备脂质体,超滤法测其包封率,以包封率为评价指标,采用Box-Behnken响应面法优化脂质体的处方工艺;考察其形态、粒径、Zeta电位、体外释放、体外透皮吸收和稳定性等理化性质;在此基础上采用MTT法考察其对HSF细胞增殖的作用,采用划痕法和Transwell小室法考察其对HSF细胞迁移和侵袭的作用。结果 SAB-TAT-LIP的药物包封率为(86.70±0.85)%,平均粒径为(219.90±5.09)nm,Zeta电位(-9.25±0.92)m V,体外24h累积释放率为62.49%,无突释效应,体外32h皮肤累积透过率为17.21%,透过速率为(28.33±4.9)μg/(cm2·h),真皮层滞留量为(44.39±6.87)μg/cm2,4℃放置10d稳定性良好。SAB-TAT-LIP能够显著地抑制HSF细胞的增殖、迁移和侵袭,与对照组相比,差异显著(P0.01)。结论优化得到的SAB-TAT-LIP包封率较高、粒径较小,体外释放和透皮行为均满足局部透皮给药制剂的体外释放和透皮规律,对体外HSF细胞的增殖、迁移和侵袭具有抑制作用。 相似文献
143.
目的传承历代中药调剂操作经验,规范现代中药小包装饮片调剂操作技术。方法通过查阅历代古籍和现代文献,系统整理和分析中药饮片小包装的历史渊源、使用利弊、包装选择、使用现状及调剂规程等五方面情况,回顾小包装饮片的发展历程,总结调剂操作经验,编排现代调剂操作规程。结果中药小包装饮片调剂具有独特的优势,"审、摆、看、对、拿、掂、分、核、包、发"的"十字口诀"是其主要操作要点。结论中药小包装饮片调剂"十字口诀"易记、易懂、易操作,提高临床调剂质量、规范调剂技能具有指导意义。 相似文献
144.
Ide J Aoki T Ishivata S Glusa E Strukova SM 《Bulletin of experimental biology and medicine》2007,144(6):760-763
We studied activation of cultured cardiomyocytes and cardiac fibroblasts from chick embryos induced by agonists of PAR1 (thrombin
and PAR1 peptide agonist) and PAR2 (trypsin, factor Xa, and peptide SLIGRL) by analyzing changes in intracellular Ca2+ concentration ([Ca2+]i) and cardiac fibroblast proliferation. Exposure of cardiomyocytes with thrombin induced immediate permanent dose-dependent
increase in [Ca2+]i. Ca2+ response decreased in a calcium-free medium. Peptide agonists of PAR1 and PAR2 also stimulated the increase in [Ca2+]i in cardiomyocytes. Thrombin induced a short-term increase in [Ca2+]i in cardiac fibroblasts and potentiated cell proliferation. PAR2 agonists trypsin and peptide SLIGRL stimulated proliferation
of cardiac fibroblasts. Our results indicate that cardiomyocytes and cardiac fibroblasts from chick embryos have at least
two types of PAR (types 1 and 2).
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 144, No. 12, pp. 609–612, December, 2007 相似文献
145.
Pleshkanyova OG Dubrovina IV Teryushkova ZhI Sukhikh GT 《Bulletin of experimental biology and medicine》2007,144(1):154-158
We studied the effects of trophoblastin and polydeoxyribonucleotide on the morphology and functional characteristics of fibroblasts
in the culture of skin cells. Positive effects of trophoblastin and polydeoxyribonucleotide on fibroblast growth and survival
during culturing were demonstrated. Trophoblastin exhibited similar effects on cells of early and late passages. Polydeoxyribonucleotide
exhibited a more pronounced effect on cells of late passages, whose growth activity decreased with age. Being a multicomponent
preparation, trophoblastin stimulated processes leading to positive dynamic of cell development and vital activity. Polydeoxyribonucleotide
had a favorable impact on functioning of basal cell structures at the level of cell nucleus and maintained high level of cells
with complete DNA set.
__________
Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 3, pp. 173–177, July, 2007 相似文献
146.
Suzdal'tseva YG Burunova VV Petrakova NV Vakhrushev IV Yarygin KN Yarygin VN 《Bulletin of experimental biology and medicine》2007,143(1):147-154
The expression of cytoplasmic and surface proteins in cultured human skin fibroblasts, human umbilical cord cells obtained
after normal delivery on gestation week 38–40, and mesenchymal bone marrow stem cells was compared by the methods of immunocytochemistry
and flow cytofluorometry. Bone marrow mesenchymal stem cells expressed a great variety of marker proteins typical of stem
and progenitor cells and did not express proteins typical of differentiated cells. Fibroblast-like umbilical cord cells expressed
markers of both stem cells and differentiated cells. Fibroblasts of dermal origin were characterized by intensive expression
of proteins typical of differentiated cells.
__________
Translated from Kletochnye Tehnologii v Biologii i Medicine, No. 1, pp. 38–45, January, 2007 相似文献
147.
目的检测甲状腺乳头状癌(papillary thyroid carcinoma,PTC)相关成纤维细胞(tumor-associated fibroblasts,TAFs)中成纤维细胞特异性蛋白-1(fibroblast-specific protein 1,FSP1/S100A4)、平滑肌肌动蛋白-ɑ(ɑ-smooth-muscle actin,ɑ-SMA)和成纤维细胞活化蛋白(fibroblast-activated protein,FAP-ɑ)的表达,探究其与PTC发生、发展的关系。方法通过免疫组化SP法检测FSP1/S100A4、ɑ-SMA、FAP-ɑ在正常甲状腺组织和PTC中的表达情况,并分析这些指标与重要临床病理参数的关系。结果FSP1/S100A4、ɑ-SMA和FAP-ɑ在PTC间质细胞中可见阳性表达,而在正常甲状腺组织的滤泡上皮或间质细胞内均不表达。患者肿瘤的大小、是否有淋巴结转移及TNM的不同分期与FAP-ɑ的阳性病例数有统计学差异(χ^2=6.833,P<0.05;χ^2=10.296,P<0.05;χ^2=4.910,P<0.05);ɑ-SMA阳性病例数在是否被膜侵犯、淋巴结转移有显著差异(χ^2=6.008,P<0.05;χ^2=11.766,P<0.05),而S100A4的阳性病例数在患者的性别、年龄、瘤体的大小、有无被膜侵犯、有无淋巴结转移及患者的TNM分期差异均没有统计学意义(P>0.05)。结论PTC中TAFs的存在可能提示肿瘤具有较强的侵袭转移能力,TAFs有望成为PTC诊疗的一个新靶点。 相似文献
148.
目的探讨脂肪干细胞来源外泌体(adipose-derived stem cell released exosomes,ADSC-Exos)对糖尿病小鼠创面愈合的影响。方法取患者自愿捐赠脂肪组织,采用酶消化法分离培养ADSCs,并于第3代细胞上清液提取Exos(ADSC-Exos);透射电镜观察ADSC-Exos形态,Western blot检测膜表面标志性蛋白Alix、CD63,纳米颗粒跟踪分析仪检测粒径分布。取患者自愿捐赠皮肤组织,采用酶消化法分离培养成纤维细胞。将PKH26标记的ADSC-Exos与第5代成纤维细胞培养,共聚焦荧光显微镜观察其能否进入细胞,采用细胞计数试剂盒8(cell counting kit 8,CCK-8)及划痕法观察ADSC-Exos对成纤维细胞增殖及迁移的影响。取24只8周龄Balb/c雄性小鼠制备糖尿病模型后,背部制备直径8 mm全层皮肤缺损创面,实验组(n=12)及对照组(n=12)创面真皮层分别注射0.2 mL ADSC-Exos及PBS。第1、4、7、11、16、21天大体观察创面愈合情况,计算创面愈合率;第7、14、21天取材,行组织学(HE及Masson)及CD31免疫组织化学染色,观察创面结构、胶原纤维及新生血管情况。结果ADSC-Exos为边缘清晰、大小分布均匀的膜性囊泡;粒径为40~200 nm,平均102.1 nm;膜表面标志性蛋白Alix、CD63均呈阳性。ADSC-Exos与成纤维细胞复合培养观察示,ADSC-Exos可进入成纤维细胞胞内,并能促进成纤维细胞增殖及迁移。动物实验显示,实验组小鼠背部创面愈合明显快于对照组,各时间点创面愈合率差异均有统计学意义(P<0.05)。与对照组比较,实验组创面结构愈合更好,愈合前期新生微血管更多,愈合后期胶原纤维沉积更多;其中,第7、14、21天创面缺损长度,第7、14天微血管数量,第14、21天胶原纤维沉积百分比,组间差异均有统计学意义(P<0.05)。结论ADSC-Exos通过促进创面血管新生以及成纤维细胞增殖、迁移和胶原合成来促进糖尿病小鼠创面愈合。 相似文献
149.
The role of gadolinium chelates in the mechanism of nephrogenic systemic fibrosis: A critical update
Jean-Marc Idée Nathalie Fretellier Caroline Robic Claire Corot 《Critical reviews in toxicology》2014,44(10):895-913
Nephrogenic systemic fibrosis (NSF) is an iatrogenic scleroderma-like fibrosing systemic disorder occurring in patients with severe or end-stage renal disease. It was established as a new clinical entity in the year 2000. A causal role for gadolinium chelates (GC), widely used as contrast agents for magnetic resonance imaging, was suggested six years later. It rapidly appeared that the occurrence of NSF was associated with prior administration of GCs with lower thermodynamic stability, leading to warnings being published by health authorities and learned societies worldwide. Although a role for the chelated form of the less stable GCs has been proposed, the most commonly accepted hypothesis involves the gradual release of dissociated gadolinium in the body, leading to systemic fibrosis. However, the entire chain of events is still not fully understood in a causal way and many uncertainties remain. 相似文献
150.
目的:建立筋骨草的显微鉴别方法。方法:采用石蜡切片、表面制片及数码显微成像等技术,研究筋骨草根、根茎、茎、叶和花等部位的显微特征。结果:确立了筋骨草根、根茎、茎、叶、花等部位的显微鉴别特征。结论:实验建立的显微鉴别特征可作为筋骨草鉴别的参考依据。 相似文献