The effects of environmental factors on some vegetative characteristics of Quercus brantii in Kouh gachan,Ilam, west of Iran

In this study the effects of environmental factors on some vegetative characteristics of Quercus brantii was investigated in Kouh gachan, Ilam, West of Iran, using multivariate analysis. Therefore 64 sample plots with a size of 200?m² were considered for measuring the vegetative parameters. Some environmental factors such as slope, aspect and soil depth were recorded in all sample plots. The Detrended Correspondence Analysis (DCA) was used to investigate the relation between vegetative parameters and environmental factors. Redundancy analysis (RDA) analysis was also used to interpret the results. The results of DCA analysis showed that the effect of environmental factors on vegetation cover is significant. Slope had the smallest and the soil depth had the biggest effect on vegetative characteristics of Quercus brantii. The results also confirmed the usage of RDA analysis for investigating the relationship between environmental factors and vegetative characteristics.     

Genotype-Phenotype Correlations in Ornithine Transcarbamylase Deficiency: A Mutation Update

Ornithine transcarbamylase(OTC) deficiency is an X-linked trait that accounts for nearly half of all inherited disorders of the urea cycle.OTC is one of the enzymes common to both the urea cycle and the bacterial arginine biosynthesis pathway; however, the role of OTC has changed over evolution. For animals with a urea cycle, defects in OTC can trigger hyperammonemic episodes that can lead to brain damage and death. This is the fifth mutation update for human OTC with previous updates reported in 1993, 1995, 2002, and 2006. In the2006 update, 341 mutations were reported. This current update contains 417 disease-causing mutations, and also is the first report of this series to incorporate information about natural variation of the OTC gene in the general population through examination of publicly available genomic data and examination of phenotype/genotype correlations from patients participating in the Urea Cycle Disorders Consortium Longitudinal Study and the first to evaluate the suitability of systematic computational approaches to predict severity of disease associated with different types of OTC mutations.     

The Neuroprotective Ability of Polyethylene Glycol is Affected by Temperature in Ex Vivo Spinal Cord Injury Model

Immediate membrane sealing after spinal cord injury (SCI) can prevent further degradation and result in ultimate functional recovery. It has been reported that polyethylene glycol (PEG) can repair membrane damage caused by mechanical insults to the spinal cord. Furthermore, membrane fluidity and its sealing process vary at different temperatures. Here, we have assessed the possible synergistic effects of PEG and temperature on the repair of neural membranes in an SCI model. The effects of PEGs (400, 1,000 and 2,000 Da) were studied at different temperatures (25, 37 and 40 °C) by means of compound action potential (CAP) recovery and a lactate dehydrogenase (LDH) assay. Isolated spinal cords were mounted in a double sucrose gap chamber, where the amplitude and area of CAPs were recorded after implementing injury, in the presence and absence of PEG. Moreover, the LDH assay was used to assess the effects of PEG on membrane resealing. Data showed that the least CAP recovery occurred at 25 °C, followed by 37 and 40 °C, in all treated groups. Moreover, maximum CAP amplitude recovery, 65.46 ± 5.04 %, was monitored in the presence of PEG400 at 40 °C, followed by 41.49 ± 2.41 % in PEG1000 and 37.36 ± 1.62 % in PEG2000. Furthermore, raising the temperature from 37 to 40 °C significantly increased CAP recovery in the PEG2000 group. Similar recovery patterns were obtained by CAP area measurements and LDH assay. The results suggest that application of low-molecular weight PEG (PEG400) in mild hyperthermia conditions (40 °C) provides the optimum condition for membrane sealing in SCI model.