Hypoxic conditioned medium derived from bone marrow mesenchymal stromal cells protects against ischemic stroke in rats

In recent years, studies have shown that the secretome of bone marrow mesenchymal stromal cells (BMSCs) contains many growth factors, cytokines, and antioxidants, which may provide novel approaches to treat ischemic diseases. Furthermore, the secretome may be modulated by hypoxic preconditioning. We hypothesized that conditioned medium (CM) derived from BMSCs plays a crucial role in reducing tissue damage and improving neurological recovery after ischemic stroke and that hypoxic preconditioning of BMSCs robustly improves these activities. Rats were subjected to ischemic stroke by middle cerebral artery occlusion and then intravenously administered hypoxic CM, normoxic CM, or Dulbecco modified Eagle medium (DMEM, control). Cytokine antibody arrays and label-free quantitative proteomics analysis were used to compare the differences between hypoxic CM and normoxic CM. Injection of normoxic CM significantly reduced the infarct area and improved neurological recovery after stroke compared with administering DMEM. These outcomes may be associated with the attenuation of apoptosis and promotion of angiogenesis. Hypoxic preconditioning significantly enhanced these therapeutic effects. Fourteen proteins were significantly increased in hypoxic CM compared with normoxic CM as measured by cytokine arrays. The label-free quantitative proteomics analysis revealed 163 proteins that were differentially expressed between the two groups, including 107 upregulated proteins and 56 downregulated proteins. Collectively, our results demonstrate that hypoxic CM protected brain tissue from ischemic injury and promoted functional recovery after stroke in rats and that hypoxic CM may be the basis of a potential therapy for stroke patients.     

Newly-formed photosynthates and the respiration rate of girdled stems of Korean pine (Pinus koraiensis Sieb. et Zucc.)

A stem-girdling experiment was carried out on an evergreen conifer, the Korean pine (Pinus koraiensis Sieb. et Zucc.), in mid summer in Northeast China. A 50 % higher respiration rate at the upper part of the stem was observed 3 d after stem girdling, and a stable higher rate (1.2–2.8 times) one week later. However, no higher soluble sugar or starch contents were found in the upper bark of the girdled stems in measurements over three weeks. These findings indicate that most of the newly-formed photosynthates were consumed by the high respiratory activity; this is also implied by the strong correlation between the photosynthetic photon flux over the canopy (PPF) and respiration at the upper parts of girdled stems. Moreover, the maximum PPF and cumulative PPF one day before measurement (PPFmax-Y and CPPF-Y, respectively) were closely correlated with the respiratory difference between the upper and the lower parts, but no such correlation was found with the instantaneous PPF (PPF-I) and cumulative PPF on the current day from sunrise to measured time point (CPPF-C). This shows that photosynthates newly formed by canopy needles need at least one day for transportation in order to increase the stem respiration at tree breast height.     

假苍耳的生活史进程中几种生理生化指标的变化

本文试图从生理生化的角度对假苍耳(Iva xanthifolia)生活史进程中可溶性糖类、赤霉素、单宁以及黄酮的变化进行探讨。通过对假苍耳在生长发育期间几种生理生化指标的测定, 结果表明, 在假苍耳生活史进程的不同阶段, 其体内各种代谢产物的含量基本都在种子或芽阶段具有最高含量。此外, 不同发育阶段可溶性还原糖含量的变化规律相似: 芽>花序>苗>成株>种子。除在花序和苗阶段没有测到海藻糖, 其他各阶段海藻糖的含量变化如下: 芽>成株>种子。另外, 只有在种子阶段检测到棉子糖, 其含量为15.43 mg.g-1。赤霉素含量的变化规律如下: 种子＞芽≈苗≈花序＞成株。单宁含量的变化趋势: 种子＞成株＞苗＞芽＞花序。黄酮含量的变化趋势: 种子＞芽＞成株≈花序＞苗。值得注意的是, 当单宁/黄酮的比值接近1时, 植物体内需要的单宁和黄酮的含量则相对较低; 相反, 当单宁/黄酮的比值接近0时, 植物体内需要的单宁和黄酮的含量则较高。     

Oncogenic GBX2 promotes the malignant behaviors of bladder cancer cells by binding to the ITGA5 promoter and activating its transcription

Functional & Integrative Genomics - In bladder cancer patients, metastasis after surgical resection and serious adverse reactions brought by cisplatin-based systemic chemotherapy make it urgent...     

piRNA-Triggered MIWI Ubiquitination and Removal by APC/C in Late Spermatogenesis

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Highlights? MIWI is a substrate of APC/C, and piRNA loading is essential for MIWI ubiquitination ? piRNA loading promotes MIWI binding to the APC/C substrate-binding subunit ? MIWI and piRNAs are coordinately eliminated in late spermatids ? Inhibition of MIWI destruction in late spermatids prevents sperm maturation     

Steady‐state and time‐resolved fluorescence of tetramethylrhodamine attached to DNA: correlation with DNA sequences

Time‐resolved fluorescence as well as steady‐state absorption and fluorescence were detected in order to study the interactions between tetramethylrhodamine (TAMRA) and DNA when TAMRA was covalently labeled on single‐ and double‐stranded oligonucleotides. Fluorescence intensity quenching and lifetime changes were characterized and correlated with different DNA sequences. The results demonstrated that the photoinduced electron transfer interaction between guanosine residues and TAMRA introduced a short lifetime fluorescence component when guanosine residues were at the TAMRA‐attached terminal of the DNA sequences. The discrepancy of two‐state and three‐state models in previous studies was due to the DNA sequence selection and sensitivity of techniques used to detect the short lifetime component. The results will help the design of fluorescence‐based experiments related to a dye labeled probe. Copyright © 2012 John Wiley & Sons, Ltd.     

少数民族林区可持续发展实证分析

本文对少数民族林区研究范畴进行了界定,通过运用AHP分析法构建可持续发展指标体系,对少数民族林区可持续发展指数和能力进行了分析,提出了少数民族林区可持续发展过程中出现的主要问题和可能影响可持续发展的各种因素。     

A rapid enzymatic assay for high-throughput screening of adenosine-producing strains

Adenosine is a major local regulator of tissue function and industrially useful as precursor for the production of medicinal nucleoside substances. High-throughput screening of adenosine overproducers is important for industrial microorganism breeding. An enzymatic assay of adenosine was developed by combined adenosine deaminase (ADA) with indophenol method. The ADA catalyzes the cleavage of adenosine to inosine and NH₃, the latter can be accurately determined by indophenol method. The assay system was optimized to deliver a good performance and could tolerate the addition of inorganic salts and many nutrition components to the assay mixtures. Adenosine could be accurately determined by this assay using 96-well microplates. Spike and recovery tests showed that this assay can accurately and reproducibly determine increases in adenosine in fermentation broth without any pretreatment to remove proteins and potentially interfering low-molecular-weight molecules. This assay was also applied to high-throughput screening for high adenosine-producing strains. The high selectivity and accuracy of the ADA assay provides rapid and high-throughput analysis of adenosine in large numbers of samples.