A deep tissue fluorescence imaging system with enhanced SHG detection capabilities

We describe a novel two‐photon fluorescence microscopy system capable of producing high‐quality second harmonic generation (SHG) images in thick turbid media by using an innovative detection system. This novel detection system is capable of detecting photons from a very large surface area. This system has proven effective in providing images of thick turbid samples, both biological and artificial. Due to its transmission detection geometry, the system is particularly suitable for detecting SHG signals, which are generally forward directed. In this article, we present comparative data acquired simultaneously on the same sample with the forward and epidetection schemes. Microsc. Res. Tech. 77:368–373, 2014. © 2014 Wiley Periodicals, Inc.     

透明质酸在皮肤创伤修复中的应用

透明质酸(HA)吸水性强、生物相容性好,在创伤愈合中具有特殊的生物活性,在创伤治疗领域中应用广泛。本文对HA在创伤敷料、皮肤组织工程等创伤修复领域中的应用进展作一综述。     

玉米淀粉乳液在B级生活用纸中的工艺实践

将玉米淀粉按比例混合,制备成玉米淀粉乳液,作为造纸湿部添加剂加入纸浆中,可增强纤维之间的连接,具有稳定纸张纹路作用,能够显著提高原纸的物理性能.该文就玉米淀粉乳液在B级生活用纸中的工艺实践与应用作了介绍.     

In vitro stability and compatibility of tenecteplase in central venous access devices

Central venous access devices (CVADs) aid in the delivery of nutritional support, infusion therapy, and hemodialysis. Maintaining continuous flow through these devices is challenging, because they are susceptible to complications such as thrombi occlusion. Therefore, CVADs may require treatment with anticoagulant or thrombolytic agents. Using these agents as locking solutions has been widely investigated; however, few publications have described the compatibility of the therapeutic with the CVAD itself. The objective of this investigation was to evaluate the in vitro stability and compatibility of a thrombolytic biologic agent, tenecteplase, with various CVAD materials. Tenecteplase was reconstituted to 1 mg/mL with either sterile water for injection or bacteriostatic water for injection (0.9% benzyl alcohol) then incubated in glass vials, polysulfone/silicone vascular access ports, and polyurethane or silicone catheters for up to 96 hours. Biochemical assays including protein monomer, protein one-chain, and in vitro bioactivity were used to assess tenecteplase's compatibility with the investigated diluents and materials every 24 hours. Antimicrobial testing was also performed for up to 28 days on bacteriostatic water for injection-reconstituted samples only. Our results showed tenecteplase to be compatible with both types of diluents (in glass vials) and catheters for up to 72 hours. Furthermore, tenecteplase was compatible with the polysulfone/silicone vascular access ports for up to 24 hours. Finally, bacteriostatic water for injection-reconstituted tenecteplase effectively met USP criteria for the inhibition of growth of micro-organisms. This study serves as an example of a best practice to evaluate the in vitro stability and compatibility of a biologic agent with CVAD materials.     

Isolation of a pollen specific promoter in tritordeum

The promoter is an important cis-acting element in regulating gene expression. Tissue specific promoters play a key role in genetic engineering. A promoterless plasmid containing UidA gene was transformed into tritordeum by barmbadment. Histochemical analysis of various tissues in transgenic tritordeum was carried to examine tissue-specific expression of GUS activity. The pollen-specific promoter was trapped and identified successfully in a transformant line. PCR method was used to isolate this pollen-specific promoter with DNA extracted from leaves as templates, using primer P1 of rice pollen specific promoter as forward primer, a fragment of UidA gene as the reverse primer P2. By sequencing and analyzing the amplified 1052bp DNA fragment from PCR reaction, a part of UidA gene and a flanking sequence were obtained. Some essential elements of plant promoters were found in the sequence. To determine the function of this promoter, the cloned promoter fragment was fused with uidA gene, then cloned into a plasmid and transformed into Triticum durum. The transgenic plant transformed by this vector showed GUS expression only in pollen. Therefore a pollen-specific promoter was trapped and isolated successfully, and it could be used in gene regulation study and genetic engineering.     

Application of flow cytometric DNA measurements in the detection of irradiated onions

Nuclei from meristem tissue cells of onion bulbs γ-irradiated (60–90 Gy) for sprout inhibition and non-irrádiated control bulbs were isolated periodically during ambient (27–32°C) storage, stained with the fluorochrome 4′,6-diamidino-2-phenylindole and their DNA distribution histograms measured by flow cytometry (FCM). Nuclei from irradiated onions showed a broader DNA distribution profile appearing as a wide (high) coefficient of variation (CV, 4–78%) of the G₀/G₁ peak as compared with non-irradiated samples (CV, 2.39%). The DNA index (DI) of the diploid cells in control onions was 1 as against 0.74 in irradiated samples which indicated the presence of G₀/G₁ cells with abnormal DNA content in the meristem tissue cells of irradiated onions. The results indicate the potential application of quantitating changes in DNA content using FCM by determining CV of the G₀/G₁ peak as well as DI for differentiating irradiated from non-irradiated onion bulbs.     

超声波对果蔬渗糖及组织细胞的影响

通过跟踪测定果蔬组织中含糖量的变化及显微切片技术 ,对超声波影响果蔬渗糖及组织细胞完整性问题进行了比较研究。结果表明 ,与常规渗糖方法相比 ,超声波提高果蔬组织渗糖速度的幅度在 3 8 63 %以上。超声波可以显著提高果蔬组织的渗糖速率 ,同时可以明显降低糖煮对果蔬组织细胞结构的破坏作用