[Study on quantificational analysis method for the non-crystalline content in blast furnace slag].

Quantificational analysis method for the non-crystalline and crystalline contents in blast furnace slag was studied by means of X-ray diffraction. The process of quantificational analysis method includes standard samples preparation, samples preparation, X-ray diffraction measurement and data treatment. The data treatment includes integration areas of non-crystalline curve and crystalline peaks in certain diffraction angle range, linear fitting and quantificational coefficient determination. The preparation methods of standard samples for X-ray diffraction of blast furnace slag were proposed, including 100% crystalline sample and 100% non-crystalline sample. The 100% crystalline sample can be obtained by heating blast furnace slag for 12 h at 1 000-1 200 degrees C, and the 100% non-crystalline sample can be obtained by quenching the molten slag with enough water. The X-ray diffraction method of quantificational analysis of non-crystalline content in blast furnace slag was proposed with the 100% non-crystalline and 100% crystalline standard samples, and the quantificational coefficient can be obtained by linear regression on the integration areas of non-crystalline curve and crystalline peaks of X-ray diffraction in the 2-theta range 20 degrees-40 degrees. This method is suitable for the blast furnace slag with the non-crystalline content over 80%. The non-crystalline and crystalline contents of original blast furnace slag are obtained by combining the X-ray diffraction results and mathematical treatment, and this method is suitable for the blast furnace slag with the non-crystalline content over 90%, whose process includes preparing the 100% crystalline standard sample by heating blast furnace slag for 12 h at 1000-1200 degrees C, samples preparation with the 0.02 interval in the 0-0.1 mass ratio range of 100% crystalline to original slag, X-ray diffraction measurement of the samples prepared and data treatment using iterative linear regression. The quantificational analysis method for blast furnace slag can be applied to various kinds of blast furnace slag from different steel plants.

The release of cytochrome c and the regulation of the programmed cell death progress in the endosperm of winter wheat (Triticum aestivum L.) under waterlogging.

It has been shown in mammalian systems that the mitochondria can play a key role in the regulation of apoptosis by releasing intermembrane proteins (such as cytochrome c) into the cytosol. Cytochrome c released from the mitochondria to the cytoplasm activates proteolytic enzyme cascades, leading to specific nuclear DNA degradation and cell death. This pathway is considered to be one of the important regulatory mechanisms of apoptosis. Previous studies have shown that endosperm cell development in wheat undergoes specialized programmed cell death (PCD) and that waterlogging stress accelerates the PCD process; however, little is known regarding the associated molecular mechanism. In this study, changes in mitochondrial structure, the release of cytochrome c, and gene expression were studied in the endosperm cells of the wheat (Triticum aestivum L.) cultivar "huamai 8" during PCD under different waterlogging durations. The results showed that waterlogging aggravated the degradation of mitochondrial structure, increased the mitochondrial permeability transition (MPT), and decreased mitochondrial transmembrane potential (ΔΨm), resulting in the advancement of the endosperm PCD process. In situ localization and western blotting of cytochrome c indicated that with the development of the endosperm cell, cytochrome c was gradually released from the mitochondria to the cytoplasm, and waterlogging stress led to an advancement and increase in the release of cytochrome c. In addition, waterlogging stress resulted in the increased expression of the voltage-dependent anion channel (VDAC) and adenine nucleotide translocator (ANT), suggesting that the mitochondrial permeability transition pore (MPTP) may be involved in endosperm PCD under waterlogging stress. The MPTP inhibitor cyclosporine A effectively suppressed cell death and cytochrome c release during wheat endosperm PCD. Our results indicate that the mitochondria play important roles in the PCD of endosperm cells and that the increase in mitochondrial damage and corresponding release of cytochrome c may be one of the major causes of endosperm PCD advancement under waterlogging.

[Isolation and Identification of Human Umbilical Cord and Placenta-derived Stem Cells and Their Component Analysis].

OBJECTIVE: Clinical transplantation evidence has been indicated that umbilical cord blood (UCB) can be useful in the hematopoietic reconstitution in the children, but can not be well in the adult hematopoietic transplantation because of the low count. This study was to evaluate a new method for collecting stem cells from human placenta and umbilical cord, and to comparatively analyze the similarity and difference of quality and quantity of the cells. METHODS: The UCB was collected, in same time the placental tissue was sterily collected; the umbilical placenta was collected by perfusing the blood (UPB) cord arterial and venous vascules with 0.9% saline; the mesenchymal stem cells (MSC) from same source of umbilical cord and placental tissues were isolated and cultured. The cell colony assay and flow cytometry were performed to determine the proliferation capacities and cell markers of UMSC and PMSC. RESULTS: The total nuclear cells (NC) and hematopoietic stem cells (CD34(+)) from UPB and UCB were (17.45 ± 16.86) × 10(8), (6.9 ± 4.61) × 10(8) and (2.97 ± 2.25) × 10(6), (1.91 ± 1.7) × 10(6), respectively. Furthermore, the UPB contained more early precursor of hematopoietic stem cells (CD33(+) CD34(-)) (6.2 ± 13.5) × 10(5), (0.2 ± 0.8) × 10(5) ; and high proportion of MSC to NC (25.21 ± 18.69, 0.05 ± 0.10)%, respectively in 62 samples. There were no difference of the MSC level in UPB and UCB, as well as in the morphology and cell markers. CONCLUSION: UPB has rich hematopoietic stem cells and mesenchymal stem cells. Placenta may offer another source for hematopoietic stem cells in research of hematopoietic stem cells and regeneration medicine.