Expression of nerve growth factor precursor, mature nerve growth factor and their receptors during cerebral ischemia-reperfusion injury

We investigated nerve growth factor precursor （proNGF） and mature NGF expression in ischemic and non-ischemic cortices after cerebral ischemia-reperfusion injury. In both ischemic and non-ischemic cortices, proNGF was found to be present in the extracellular space and cytoplasm. In addition, mature NGF was expressed in extracellular space, but with a very low signal. In ischemic cortex only, proNGF was significantly decreased, reaching a minimal level at 1 day. Mature NGF was increased at 4 hours, then reached a minimal level at 3 days. The p75 neurotrophin receptor （p75NTR） was significantly decreased after ischemia, and increased at 3 days after ischemia. These results confirmed that proNGF was the predominant form of NGF during the pathological process of cerebral ischemia-repeffusion injury. In addition, our findings suggest that ischemic injury may influence the conversion of proNGF to mature NGF, and that proNGF/p75NTR may be involved in reperfusion injury.

EXPRESSING HUMAN MATURED BRAIN-DERIVED NEUROTROPHIC FACTOR GENE IN E.Coli AND DETERMINING ITS BIOACTIVITY

Objective Expressing the human matured brain-derived neurotrophic factor (mBDNF) gene in E. Coli and determining its bioactivity. Methods The resulting gene of mBDNF was subcloned into the EcoRI-BamHI site or the expression vector plasmid pBV220. The ligation products were used to transform the competent E. Coli DH5a. The proteins or mBDNF were experessed by temperature inducing. The expression products were dealed with solubilizing inclusion bodies and refolding protein. It was introduced into the embryonic chicken DRG to test whether the expressed mBDNF is a biologically active protein. Results The recombinant plasmid pBV/mBDNF was success- fully constructed. By temperature inducing, under the control of the bacteriophage λPL promoter, the experessed mBDNF protein was a 14Kd non-fusion protein,which existed in E. Coli as inclusion bodies. The size or expressed mBDNF is identical to the prediction. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of embryonic 8-day-old chicken DRG neurons as compared to control. Conclusion Tke mBDNF gene can be expressed bioactively in E. Coli.

Seepage Mitigation in Hydropower Dams by Optimization in Roller Compacted Concrete Interlayer (Monoliths) Joint Bonding Technology

Roller Compacted Concrete (RCC) has gained favorable recognition in hydropower and water resource dam construction. With optimization in construction technology and materials used for RCC Dams, cost is no longer a major disadvantage as compared to environmental impact, that is, wildlife habitat disruption. In as much as it has become optimal for investment in hydropower dam construction, the scourge for dam failure is still eminent, which is as a result of excessive seepage compromising the integrity of the mechanical properties of the dam. The aim of the paper is to highlight successful application methods in joint bonding to avoid excessive seepage and reduce the autogenous healing to a few years of operation. In view of optimization, this paper presents a comprehensive study on the influences of interlayer joints bonding quality from RCC mix performances and how it consolidates the RCC layers to withstand the shear strength along the interface, especially on the high dams. The case study is the RCC dam at the 750 MW Kafue Gorge Lower Hydropower Station. The scope of the study reviews the joint type judged by Modified Maturity Factor (MMF) with joint surface long time exposed in regions with dry and high temperature, technical measures of layer bonding quality control under condition of long time joint surface exposure, effects of joints shear strength and impermeability of the RCC layers when under the conditions of plastic and elasticity. The subtle observations made during the dam construction phases were with respect to the optimal use of materials in relation to RCC mix designs and the basis for equipment calibration for monitoring important data that can be referenced during analysis of shear forces acting on the RCC dam over time.

An Investigation of Polymorphism in <i>SMO</i>and <i>LMF</i>1 Genes and Their Association with Body Size in White Fulani and Muturu Cattle Breeds

Cattle production is integral to the people of Africa and her economy. To improve cattle productivity, there is a need to inculcate molecular marker-assisted selection into current breeding practices. In this study, we investigated, in White Fulani and Muturu cattle breeds, polymorphism of two candidate genes (Smoothened—SMO and Lipase Maturation Factor 1—LMF1) that have been reported to influence body size in cattle. The SMO gene encodes for the SMO (smoothened) receptor protein;a membrane signal transducer that plays a role in the control of bone formation and adipogenesis. LMF1 encodes for the LMF1 protein which regulates post-translational maturation of vascular lipases. Desired regions of the genes were amplified and genotyped by direct DNA sequencing or Polymerase chain reaction—Restriction Fragment Length Polymorphism. For association study, linear body measurements traits (BMTs) that can be used to predict body size were measured on each animal and values of BMTs measured were compared between both breeds. Very significant (P < 0.001) differences, in favour of White Fulani, were observed for all the BMTs compared. Six (6) previously reported SNP (G21234C, C22424T and C22481T, T22939C, C23329T and T23458G) were found on the SMO while LMF1 was monomorphic at the expected (T > C) exon 4 mutation site. Association analysis revealed that polymorphism on G21234C, C22424T, T22939C and T23458G loci significantly affected BMTs (P < 0.05 or 0.01) in both cattle breeds. The outcome of this study showed that SMO gene could be a useful candidate gene to facilitate marker assisted selection for body size while LMF1 is monomorphic in the cattle breeds.

Brain-Derived Glia Maturation Factor b Participates in Lung Injury Induced by Acute Cerebral Ischemia by Increasing ROS in Endothelial Cells

Brain damage can cause lung injury. To explore the mechanism underlying the lung injury induced by acute cerebral ischemia(ACI), we established a middle cerebral artery occlusion(MCAO) model in male Sprague-Dawley rats. We focused on glia maturation factor b(GMFB) based on quantitative analysis of the global rat serum proteome.Polymerase chain reaction, western blotting, and immunofluorescence revealed that GMFB was overexpressed in astrocytes in the brains of rats subjected to MCAO. We cultured rat primary astrocytes and confirmed that GMFB was also up-regulated in primary astrocytes after oxygen-glucose deprivation(OGD). We subjected the primary astrocytes to Gmfb RNA interference before OGD and collected the conditioned medium(CM) after OGD.We then used the CM to culture pulmonary microvascular endothelial cells(PMVECs) acquired in advance and assessed their status. The viability of the PMVECs improved significantly when Gmfb was blocked. Moreover,ELISA assays revealed an elevation in GMFB concentration in the medium after OGD. Cell cultures containing recombinant GMFB showed increased levels of reactive oxygen species and a deterioration in the state of the cells.In conclusion, GMFB is up-regulated in astrocytes after ACI, and brain-derived GMFB damages PMVECs by increasing reactive oxygen species. GMFB might thus be an initiator of the lung injury induced by ACI.