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991.
Mirela Sedic Lee A. Gethings Johannes P.C. Vissers John P. Shockcor Stephen McDonald Olga Vasieva Maja Lemac James I. Langridge Danica Batinić Sandra Kraljević Pavelić 《Biochemical and biophysical research communications》2014
Idiopathic nephrotic syndrome (INS) is caused by renal diseases that increase the permeability of the glomerular filtration barrier without evidence of a specific systemic cause. The aim of the present work was to reveal inherent molecular features of INS in children using combined urinary proteomics and metabolomics profiling. In this study, label-free mass spectrometric analysis of urinary proteins and small molecule metabolites was carried out in 12 patients with INS versus 12 sex- and age-matched control subjects with normal renal function. Integration and biological interpretation of obtained results were carried out by Ingenuity IPA software. Validation of obtained proteomics data was carried out by Western blot method. Proteomics data have been deposited to the ProteomeXchange Consortium with the data set identifier PXD000765. This study indicates for the first time that paediatric INS is associated with up-regulation of afamin, hydroxyphenylacetate and uridine, and concomitant down-regulation in glutamine and phenylalanine levels, and many of these molecular species were previously shown to be involved in oxidative stress. Further studies in larger patient population are underway to investigate the role of oxidative stress in renal injury in paediatric INS. 相似文献
992.
993.
Milena Niño Kurt P. McLaren Henrik Meilby Mathieu Lévesque Byron Wilson Morag McDonald 《Plant Ecology》2014,215(10):1081-1097
We used data from experimental plots (control, partially cut and clear-cut) established in 1998, in a tropical dry forest (TDF) in Jamaica, to assess changes in above ground biomass (AGB) 10 years after disturbance. The treatments reduced AGB significantly in 1999 (partially cut: 37.6 %, clear-cut: 94.4 %) and after 10 years, AGB did not recover overall, nor did it recover in the clear-cut plots. Partially cut plots, however, recovered the lost AGB in 10 years via growth of uncut trees, which contributed significantly to biomass recovery, with only minor contributions from recruited trees and coppice shoots. For clear-cut plots, coppice shoots contributed significantly to the recovered AGB when compared with recruited biomass. Together, they recovered 26 % of AGB lost, despite recovering 78 % of the density and height of the control plots. The probability of survivorship decreased for trees with higher pre-treatment AGB values, but was higher for trees with multiple stems in 1998, regardless of treatment. The magnitude of biomass reduction varied among the species assessed and this had a differential effect on their ability to recover AGB. We estimate that it will take approximately 45.4 years for the clear-cut plots to recover pre-treatment AGB; this is significantly longer than AGB recovery time for some successional rainforests on abandoned pastures/farmland. Consequently, this TDF may not be as resilient as tropical rainforests. 相似文献
994.
995.
Eleonora Distrutti Julie-Ann O’Reilly Claire McDonald Sabrina Cipriani Barbara Renga Marina A. Lynch Stefano Fiorucci 《PloS one》2014,9(9)
The intestinal microbiota is increasingly recognized as a complex signaling network that impacts on many systems beyond the enteric system modulating, among others, cognitive functions including learning, memory and decision-making processes. This has led to the concept of a microbiota-driven gut–brain axis, reflecting a bidirectional interaction between the central nervous system and the intestine. A deficit in synaptic plasticity is one of the many changes that occurs with age. Specifically, the archetypal model of plasticity, long-term potentiation (LTP), is reduced in hippocampus of middle-aged and aged rats. Because the intestinal microbiota might change with age, we have investigated whether the age-related deficit in LTP might be attenuated by changing the composition of intestinal microbiota with VSL#3, a probiotic mixture comprising 8 Gram-positive bacterial strains. Here, we report that treatment of aged rats with VSL#3 induced a robust change in the composition of intestinal microbiota with an increase in the abundance of Actinobacteria and Bacterioidetes, which was reduced in control-treated aged rats. VSL#3 administration modulated the expression of a large group of genes in brain tissue as assessed by whole gene expression, with evidence of a change in genes that impact on inflammatory and neuronal plasticity processes. The age-related deficit in LTP was attenuated in VSL#3-treated aged rats and this was accompanied by a modest decrease in markers of microglial activation and an increase in expression of BDNF and synapsin. The data support the notion that intestinal microbiota can be manipulated to positively impact on neuronal function. 相似文献
996.
Sunil V. Badve Sanjoy K. Paul Kerenaftali Klein Philip A. Clayton Carmel M. Hawley Fiona G. Brown Neil Boudville Kevan R. Polkinghorne Stephen P. McDonald David W. Johnson 《PloS one》2014,9(12)
Objectives
To study the body mass index (BMI) trajectory in patients with incident end-stage kidney disease and its association with all-cause mortality.Methods
This longitudinal cohort study included 17022 adult patients commencing hemodialysis [HD] (n = 10860) or peritoneal dialysis [PD] (n = 6162) between 2001 and 2008 and had ≥6-month follow-up and ≥2 weight measurements, using the Australia and New Zealand Dialysis and Transplant Registry data. The association of time-varying BMI with all-cause mortality was explored using multivariate Cox regression models.Results
The median follow-up was 2.3 years. There was a non-linear change in the mean BMI (kg/m2) over time, with an initial decrease from 27.6 (95% confidence interval [CI]: 27.5, 27.7) to 26.7 (95% CI: 26.6, 26.9) at 3-month, followed by increments to 27.1 (95% CI: 27, 27.2) at 1-year and 27.2 (95% CI: 26.8, 27.1) at 3-year, and a gradual decrease subsequently. The BMI trajectory was significantly lower in HD patients who died than those who survived, although this pattern was not observed in PD patients. Compared to the reference time-varying BMI category of 25.1–28 kg/m2, the mortality risks of both HD and PD patients were greater in all categories of time-varying BMI <25 kg/m2. The mortality risks were significantly lower in all categories of time-varying BMI >28.1 kg/m2 among HD patients, but only in the category 28.1–31 kg/m2 among PD patients.Conclusions
BMI changed over time in a non-linear fashion in incident dialysis patients. Time-varying measures of BMI were significantly associated with mortality risk in both HD and PD patients. 相似文献997.
Purpose
Superimposition of two dimensional preoperative and postoperative facial images, including radiographs and photographs, are used to evaluate the surgical changes after orthognathic surgery. Recently, three dimensional (3D) imaging has been introduced allowing more accurate analysis of surgical changes. Surface based registration and voxel based registration are commonly used methods for 3D superimposition. The aim of this study was to evaluate and compare the accuracy of the two methods.Materials and methods
Pre-operative and 6 months post-operative cone beam CT scan (CBCT) images of 31 patients were randomly selected from the orthognathic patient database at the Dental Hospital and School, University of Glasgow, UK. Voxel based registration was performed on the DICOM images (Digital Imaging Communication in Medicine) using Maxilim software (Medicim-Medical Image Computing, Belgium). Surface based registration was performed on the soft and hard tissue 3D models using VRMesh (VirtualGrid, Bellevue City, WA). The accuracy of the superimposition was evaluated by measuring the mean value of the absolute distance between the two 3D image surfaces. The results were statistically analysed using a paired Student t-test, ANOVA with post-hoc Duncan test, a one sample t-test and Pearson correlation coefficient test.Results
The results showed no significant statistical difference between the two superimposition methods (p<0.05). However surface based registration showed a high variability in the mean distances between the corresponding surfaces compared to voxel based registration, especially for soft tissue. Within each method there was a significant difference between superimposition of the soft and hard tissue models.Conclusions
There were no significant statistical differences between the two registration methods and it was unlikely to have any clinical significance. Voxel based registration was associated with less variability. Registering on the soft tissue in isolation from the hard tissue may not be a true reflection of the surgical change. 相似文献998.
999.
A total of 1673 Mycosphaerella graminicola strains were assayed for DNA fingerprints and restriction fragment length polymorphism (RFLP) markers in the nuclear and mitochondrial genomes. The isolates were collected from 17 wheat fields located in 11 countries on five continents over a six year period (1989-1995). Our results indicate that genetic diversity in the nuclear genome of this fungus was high for all but three of the field populations surveyed and that populations sampled from different continents had similar frequencies for the most common RFLP alleles. Hierarchical analysis revealed that more than 90% of global gene diversity was distributed within a wheat field, while approximately 5% of gene diversity was distributed among fields within regions and approximately 3% was distributed among regions on different continents. These findings suggest that gene flow has occurred on a global scale. On average, each leaf was colonized by a different nuclear genotype. In contrast, only seven mtDNA haplotypes were detected among the 1673 isolates and the two most common mtDNA haplotypes represented approximately 93% of the world population, consistent with a selective sweep. Analysis of multilocus associations indicated that all field populations were in gametic equilibrium, suggesting that sexual recombination is a regular occurrence globally. 相似文献
1000.
Jaroch S Hölscher P Rehwinkel H Sülzle D Burton G Hillmann M McDonald FM 《Bioorganic & medicinal chemistry letters》2002,12(18):2561-2564
Dihydroquinolines have been synthesized and have been shown to be potent n-NOS inhibitors. Selectivity versus e-NOS was increased to approximately 100-fold through appropriate substitution at the benzene ring. 相似文献