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112.
Imaging mass spectrometry (IMS) is an emergent and innovative approach for measuring the composition, abundance and regioselectivity of molecules within an investigated area of fixed dimension. Although providing unprecedented molecular information compared with conventional MS techniques, enhancement of protein signature by IMS is still necessary and challenging. This paper demonstrates the combination of conventional organic washes with an optimized aqueous‐based buffer for tissue section preparation before matrix‐assisted laser desorption/ionization (MALDI) IMS of proteins. Based on a 500 mM ammonium formate in water–acetonitrile (9:1; v/v, 0.1% trifluororacetic acid, 0.1% Triton) solution, this buffer wash has shown to significantly enhance protein signature by profiling and IMS (~fourfold) when used after organic washes (70% EtOH followed by 90% EtOH), improving the quality and number of ion images obtained from mouse kidney and a 14‐day mouse fetus whole‐body tissue sections, while maintaining a similar reproducibility with conventional tissue rinsing. Even if some protein losses were observed, the data mining has demonstrated that it was primarily low abundant signals and that the number of new peaks found is greater with the described procedure. The proposed buffer has thus demonstrated to be of high efficiency for tissue section preparation providing novel and complementary information for direct on‐tissue MALDI analysis compared with solely conventional organic rinsing. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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114.
The most challenging task of creating a bioengineered ovary to restore fertility in cancer patients is choosing an appropriate biomaterial to encapsulate isolated preantral follicles and ovarian cells. In this study, as a biocompatible and biodegradable biomaterial containing fibrin-like bioactivity and manageable physical properties, PEGylated fibrin aims to encapsulate isolated ovarian stromal cells as a first step of creating an engineered ovarian tissue. For this purpose, human ovarian stromal cells were isolated from frozen-thawed ovarian tissue and cultured in the PEGylated fibrin hydrogels (PEG:Fib), which were fabricated by combining two different molar ratios of PEG:Fib (10:1 and 5:1) and two thrombin concentrations. The samples were analyzed at days 0 and 5 of in vitro for cell density, proliferation (Ki67), and apoptosis (caspase-3). Moreover, LIVE/DEAD and PrestoBlue assays assessed cell viability and proliferation on days 1, 3, and 5. The effect of PEGylation on the biodegradation behavior of fibrin was evaluated by measuring the remaining mass ratio of non-modified fibrin, PEG:Fib 10:1, and PEG:Fib 5:1 hydrogels after 1, 2, 3, 5, 8, 11, and 15 days. The results showed that PEGylated fibrin hydrogels enhanced scaffold stability and supported cell viability and proliferation. In addition, PEG:Fib 5:1 T50 indicated a significantly higher cell density dynamic and non-significantly lower expression of caspase-3 on day 5. Besides, uniformity of cell distribution inside the hydrogel and a tendency to a high rate of Ki67-positive cells was observed in PEG:Fib 10:1 T50 hydrogels. In conclusion, this study reveals the positive effects of PEGylated fibrin hydrogels on isolated human ovarian stromal cells. Based on such promising findings, we believe that this matrix should be tested to encapsulate isolated human ovarian follicles. 相似文献
115.
miRNA has recently emerged as a potential biomarker for breast cancer. Even though many studies have identified ethnic variation affecting miRNA regulation, the effect of cancer stage within specific ethnicities on miRNA epigenetic remains unclear. The present study is designed to investigate miRNA regulation from two distinct ethnicities in specific cancer stages (non-Hispanic white and non-Hispanic black) using the TCGA dataset. Differentially expressed miRNAs were calculated by using the edgeR package. miRNAs with the highest or lowest log fold Change from each cancer stage were selected as a potential biomarker. miRNA-gene interaction was analyzed by using spearman correlation analysis, CLUEGO, and DIANA-mirpath. The association of biomarker candidates with diagnostic and prognostic performance was assessed using ROC and Kaplan-Meier survival analysis. miRNA-gene interaction analysis revealed the involvement of selected miRNAs in cancer progression. From eleven selected aberrant miRNAs, four of the miRNAs (hsa-mir-495, hsa-mir-592, hsa-mir-6501, and hsa-mir-937) are significantly detrimental to breast cancer diagnosis and prognosis. Hence, our result provides valuable information to explore miRNA’s role in each cancer stage between non-Hispanic white and non-Hispanic black. 相似文献
116.
将香焦组织与氧电极偶合,制成了草酸生物组织电极。在静态和流动条件下,测得电极的线性响应范围分别为8.8×10~(-5)~6.3×10~(-4)mol/L和5.0×10~(-5)~1.8×10~(-3)mol/L,二者的相关系数均为0.9998。研究了介质条件、pH、温度、流速、取样量和固定化等条件的影响。测定了电极的选择性和使用寿命等性能。计算了该实验条件下酶反应的米氏常数。采用静态法和流动注射法测得7份草酸标液的平均回收率分别为98.4%和98.9%。电极已用于一些食品中草酸的测定,所得结果与文献报道基本一致。 相似文献
117.
The morphologically undifferentiated cells of nonregenerant callous tissue of Cereus peruvianus cultured in the original medium and in medium supplemented with tyrosine were used as an alkaloid source. Comparison of alkaloid
production by C. peruvianus plants and by callous tissues indicated that alkaloid levels were almost twice as high in callous tissues as in shoots of
C. peruvianus plants. The ratio of alkaloid concentration between mature plant and morphologically und ifferentiated cells of callous tissue
was 1∶1.7. A relationship between culture medium containing tyrosine and alkaloid production was also observed in the callous
tissues of C. peruvianus. Since increased alkaloid production may be induced by additional factors such as tyrosine, increasing levels of tyrosine
or other conditions of the culture medium may be considered factors for inducing higher alkaloid production by C. peruvianus callous tissues. 相似文献
118.
乳腺癌与血清微量元素关系的分析 总被引:2,自引:0,他引:2
经临床、病理、放射或CT检查确诊的22名乳腺癌患者。在放疗前后分析血清中Fe、Zn、Cu、Mn、Se、Cr、Co、Ni的含量。结果显示:1.乳腺癌患者与健康人比较Cu、Ni含量增加,而Fe、Zn含量减少;2.健康人锌与其他元素的比值与乳腺癌患者比较,Fe/Zn上升,而Cu/Zn下降;3.乳腺癌患者放疗后与放疗前比较,Zn、Fe、Se、Co含量降低,而Cu、Ni含量增加,因此放疗时要针对降低元素给予合理的补充。 相似文献
119.
Role of Regulatory Peptide in Pathogenesis of Shock 总被引:1,自引:0,他引:1
The present study evaluated the pathogenetic roles of three kinds of regulatory peptide. The results showed that (i) plasma endothelin(ET) level elevated significantly in septic shock rats, persistent intravenous drip of low doses ET caused development of shock state in normal rats and the irreversible outcome of light hemorrhagic shock. Furthermore, i. v. administration of specific ET-antiserum was significantly effective to septic shock rats, (Ⅱ) Plasma calcitonin gene-related peptide (CGRP) increased by 260% in septic shock rats, i. v. drip of low doses CGRP both in early and late sepsis were effective to shock rats, (Ⅱi) An-giotensin-Ⅱ (ANG-Ⅱ) contents of heart and aorta increased dramatically both in early and late septic shock, and inhibiting its increase with Captopril in late sepsis significantly improved the shock state, but results were inverse in early sepsis. It could be concluded that ET was one of the most important factors participating in the pathogenesis of shock, CGRP had a compens 相似文献
120.
The DNA fragment corresponding to the tissue plasminogen activator (tPA) sequence 174-262 (Kringle-2 domain) has been synthesized by using the solid phase phosphotriester method. The Kringle-2 domain of human tPA was expressed in Escherichia colt by secretion into the periplasmic space using the Lpp-Lac promoter and PIN-Ⅲ OmpA2 signal sequence. About two thirds of the expression product was secreted into the periplasmic space , and purified with ammonium sulfate fractionation, affinity chro-matography on Lysine-Sepharose, and FPLC-Mono Q exchange chromatography. The amino acid composition observed from the Kringle-2 purified from E. coli is identical with that expected for the 174-262 fragment of human tPA. Radio binding assay shows that the recombinant Kringle-2 domain possesses the activity of fibrin binding. 相似文献