Protein microarray biosensors based on imaging ellipsometry techniques and their applications

After years of development, biosensors based on imaging ellipsometry and biosensors based on total internal reflection imaging ellipsometry have been successfully implemented in various engineering systems. Their experimental setups, detection principles, and biological and clinical applications are briefly reviewed.     

Isolation of Fucoxanthin from the Rhizoid of Laminaria japonica Aresch

Fucoxanthin was extracted from the intact rhizoid of Laminariajaponica Aresch with dimethyl sulfoxide （DMSO）, and then recovered from the DMSO extract by partitioning into ethyl acetate and subsequent evaporation. Some isolation conditions such as solvent volume and extraction time were screened. The quantity and quality of the extracted fucoxanthin were determined by spectral analysis （absorption spectra and fluorescence emission spectra）. The results indicated that： （1） the average total content of fucoxanthin was 122.1μg in 1 g of fresh L. japonica rhizoid; （2） in comparison with the widely used organic solvent, acetone, DMSO was much more effective for the extraction of fucoxanthin; （3） both DMSO volume and extraction time influenced extraction efficiency such as the recovery rate and purity of fucoxanthin （1 g of fresh L. japonica rhizoid treated with 4 mL DMSO for 60 min, yielded 〉 88% of the total fucoxanthin with purity 0.63）; （4） when （NH4）2SO4 concentration was in the range of 0.5-1.0 mol/L, the pigments rapidly and entirely moved from DMSO into the ethyl acetate phase; （5） the ethyl acetate and DMSO were recycled using a rotary evaporator.     

Creation of Transgenic Bananas Expressing Human Lysozyme Gene for Panama Wilt Resistance

Human lysozyme （HL） inhibits Fusarium oxysporum （FocR4） growth in vitro. To obtain transgenic bananas （Musa spp.） that are resistant to Panama wilt （F. oxysporum）, we introduced an HL gene that is driven by a constitutive cauliflower mosaic virus 35S promoter into the banana via Agrobacteriummediated transformation. PCR confirmed that 51 transgenic plants were obtained. The development of Panama wilt symptoms were examined after the plants had been grown in pots. The non-transgenic plants developed typical fusarium symptoms 60 d after FocR4 inoculation, whereas 24 of 51 transgenic plants remained healthy. The transgenic banana plants that showed resistance to FocR4 in the pots were then planted in a field that was heavily infected with FocR4 for further investigation. Eleven of 24 plants devel- oped symptoms before bud emergence; another 11 plants showed symptoms after bud emergence and the remaining two plants, H-67 and H-144, remained healthy and were able to fruit. Northern blotting analysis demonstrated that H-67 and H-144, bearing the strongest resistance to Panama wilt, had the highest level of HL expression and that the expression of HL was well correlated with the FocR4 resistance of transgenic plants. We conclude that Agrobacterium-mediated transformation, with the assistance of particle bombardment, is a powerful approach for banana transformation and that a transgenic HL gene can cause resistance of the crop to FocR4 in the field.     

Hydro-ecological effects of artificial Pinus tabulaeformis carr. and Hippophae rhamnoides woods in the low mountainous upland of Western Liaoning Province, China

Pinus tabulaeformis carr. and Hippophae rhamnoides are widely planted in the low mountainous upland and loess plateau and are the main species for afforestation in the semiarid region. To expound their roles in controlling severe soil and water losses and the mechanism of their roles, a study on the hydro-ecological effects of the woods was carried out during 2002–2004, using the runoff plot method set up in different woods and conducting a physical and chemical analyses of the soil. The experimental woods are located in the low mountainous upland of Western Liaoning Province, China where the annual average air temperature is 5.4–8.7°C, the annual precipitation is 450–580 mm, of which June averages 238.9 mm, and the annual average humidity is 38%–82%. The coverage rate of vegetation is 28%. The age of Pinus tabulaeformis carr. is 28 a, its distribution density is 2825 ind.·hm2, and its coverage rate is 0.75, while those of Hippophae rhamnoides are 11a, 8950 ind.·hm² and 0.90, respectively. The results showed that the intercepting rates of canopy in Pinus tabulaeformis carr. and Hippophae rhamnoides were 23.08% and 32.28%. The litter intercepting rate averaged 14.17% in the Pinus tabulaeformis carr. woods and 20.8% in the Hippophae rhamnoides woods, respectively. The runoff depths in Pinus tabulaeformis carr. and Hippophae rhamnoides were 2.516 mm and 0.893 mm, while erosion amounts were 15.57 t·km^?2 and 0.76 t·km^?2, respectively. Under the comprehensive action in the artificial woods, the runoff depth and erosion amount from the woodland were 1/20 and 1/50 of those from the wasteland, respectively, which indicated the immense hydro-ecological functions of Pinus tabulaeformis carr. and Hippophae rhamnoides woods Litter and dead roots would decompose into organic matter and nutrient substances with the help of microbes, and would thus distinctly improve the physical and chemical properties of the soil. In comparison with the wasteland, the bulk density of soil decreased in the woodland, while the content of organic matter, total N, total K, and available K significantly increased. The physical properties of soil in the woodland, such as total porosity, noncapillary porosity, saturated moisture content, noncapillary water-holding capacity, were distinctly higher in surface soil (0–20 cm) than those in the soil at the depth of 20–40 cm. There was no significant difference of pH, total P, and available P among different land types or at different soil depths. The noncapillary water-holding capacities in Pinus tabulaeformis carr. and Hippophae rhamnoides were 182.1% and 275.9% times those of wasteland, respectively.     

Efficient cardiomyocyte differentiation of embryonic stem cells by bone morphogenetic protein-2 combined with visceral endoderm-like cells

As the signals required for cardiomyocyte differentiation and functional regulation are complex and only partly understood, the mechanisms prompting the differentiation and specification of pluripotential embryonic stem (ES) cells into cardiomyocytes remain unclear. We hypothesized that a combined technology system, cocultured with a visceral endoderm (VE) - like cell line, END-2, and added cytokine BMP-2, would induce high percentage conversion of murine ES-D3 cell line into cardiomyocytes, and derived cardiomyocytes in this system would exhibit more mature characteristics. It was observed that 92% (P<0.01) ES cell-derived aggregates in this system exhibited rhythmic contractions, and the contractile areas were greater. By contrast, in ES cells cultured alone, on the feeder layer of END-2 cells, or with added BMP-2, the total percentage of beating aggregates was 19, 69 (P<0.01) and 44% (P<0.01), respectively. All the rhythmically contractile cells derived from ES cells expressed cardiac-specific proteins for troponin T. Among them, the combined system resulted in significantly increased cardiac-specific genes (NKx2.5, alpha-MHC). Transmission electron microscopy (TEM) revealed varying degrees of myofibrillar organization, and the combined system resulted in a more mature phenotype such as Z bands, nascent intercalated discs and gap junctions. Before shifting to the cardiomyocyte phenotype, this system could accelerate apoptosis of the cell population (P<0.01). The inductive efficacy of this system can provide an opportunity to facilitate cardiomyocyte differentiation of ES cells. The inducible effects of this system may depend on increasing cardiac-specific gene expression and the induction of apoptosis in cells that are not committed to cardiac differentiation.     

多重耐药鲍曼不动杆菌同源性分析

目的研究台州医院中心重症监护病房（ICU）及脑外重症监护病房（SICU）2006年1月出现的多重耐药鲍曼不动杆菌（MDR-AB）的耐药性、碳青霉烯酶基因型及同源性。方法运用VITEK-60全自动微生物仪对分离自2006年1月ICU和SICU患者多重耐药鲍曼不动杆菌8株进行菌种的重新鉴定,采用微量板稀释法测定β-内酰胺类、氨基糖苷类、氟喹喏酮类等17种抗菌药物的体外最低抑菌浓度（MIC）（其中头孢哌酮／舒巴坦、美洛配能采用K-B法测定耐药性）。采用PCR对8株菌株进行OXA型碳青霉烯酶基因型检测,运用脉冲场凝胶电泳分析菌株的同源性。结果8株菌株仅对头孢哌酮／舒巴坦敏感,对头孢菌素类、氨基糖苷类、氟喹喏酮类和碳青霉烯类等抗菌药物均显示出较高水平的耐药;8株菌株均产OXA-23型碳青霉烯酶;脉冲场凝胶电泳证实其为同一克隆。结论本组鲍曼不动杆菌为多重耐药株,同一克隆株在不同感染个体的相互传播,导致了这次院内感染的流行。     

脂多糖诱导肝细胞HepG2释放HMGB-1的研究

观察小剂量LPS(lipopolysaccharide)刺激下非坏死HepG2细胞是否存在HMGB1(high mobility group box-1 protein)移位及释放.以终浓度为100μg/L的LPS作用HepG2和RAW264.7细胞0、4、8、12、16、20、24h.LPS作用16~24h,HepG2和RAW264.7细胞培养上清中均可以检测到明显的HMGB1,与对照组差别有显著性(P<0.05).而MTT法和上清中LDH(lactate dehydrogenase)含量测定显示,LPS处理24h的HepG2存活率仍然非常高.免疫荧光观察到HMGB1的释放伴随着其从细胞核向胞浆的移位.由此可见,经LPS诱导,非坏死状态的HepG2细胞可发生HMGB1的移位及释放.     

The Syndrome of Sea Cucumber （Apostichopusjaponicus） Infected by Virus and Bacteria

A outbreak of disease with symptoms of evisceration and skin ulteration led to mass mortality in sea cucumber Apostichopus japonicus cultivated in indoor ponds near the Dalian coast from December 2004 to April 2005. Spherical virus particles with a diameter of 75-200 nm were found in the cytoplasm of cells in the water-system, the alimentary canal and in the respiratory trees of the diseased and dying sea cucumber individuals by electron microscopic observation of ultrathin sections. Examination by negative stained samples revealed that all the diseased sea cucumbers were infected by the virus, while the healthly ones cultivated outside the contagious area were not. Two bacterial strains were also isolated from the diseased animals. When exposed to a medium containing the virus particles, regardless of whether the bacterial suspension was added, healthy sea cucumbers exhibited identical disease symptoms as the ones in the indoor ponds, and had a mortality of 90%-100%. However, when exposed to a medium in which there was only one of the two bacterial strains, 30%-80% of the sea cucumbers were infected and nearly 20% died. Negative staining showed that the viral particles were detected only in the bodies of the tested animals that were exposed to the viral medium Histopathologically, the diseased sea cucumbers are characterized by karyopycnosis, and disintegration of the endoplasmic reticula and mitochondria in the epithelial cells in the water-system, the respiratory tree and the alimentary canal.     

清洁级、SPF级SD大鼠血液生理、生化测定与比较

目的 测定清洁级、SPF级SD大鼠血液生理、生化指标并进行比较,了解不同环境SD大鼠血液生理、生化指标的差异.方法 利用法国产BASIC半自动血液生化分析仪和意大利产HS-18全自动血球计数仪对不同环境SD大鼠10项血液生化值和18项血液常规值进行测定.结果 清洁级、SPF级SD大鼠葡萄糖(GLU)、总胆固醇(TC)、白细胞(WBC)、血红蛋白(HGB)、平均红细胞血红蛋白浓度(MCHC)、血小板(PLT)、血小板比积(PCT)、血小板平均体积(MPV)比较有非常显著差异;丙氨酸氨基转移酶(ALT)、红细胞(RBC)比较有极显著差异;红细胞比积(HCT)比较有显著差异.结论 不同环境对SD大鼠血液生理、生化测定结果有较大影响.