Avoiding Loss of Catalytic Activity of Pd Nanoparticles Partially Embedded in Nanoditches in SiC Nanowires

Nanoditches from selective etching of periodically twinned SiC nanowires were employed to hinder the migration and coalescence of Pd nanoparticles supported on the nanowires, and thus to improve their catalytic stability for total combustion of methane. The results show that the etched Pd/SiC catalyst can keep the methane conversion of almost 100% while the unetched one has an obvious decline in the catalytic activity from 100 to 82% after ten repeated reaction cycles. The excellent catalytic stability originates from the limitation of the nanoditches to the migration and growth of Pd nanoparticles

Quantitative Analysis and Comparison Study of [18F]AlF-NOTA-PRGD2, [18F]FPPRGD2 and [68Ga]Ga-NOTA-PRGD2 Using a Reference Tissue Model

With favorable pharmacokinetics and binding affinity for αvβ3 integrin, 18F-labeled dimeric cyclic RGD peptide ([18F]FPPRGD2) has been intensively used as a PET imaging probe for lesion detection and therapy response monitoring. A recently introduced kit formulation method, which uses an 18F-fluoride-aluminum complex labeled RGD tracer ([18F]AlF-NOTA-PRGD2), provides a strategy for simplifying the labeling procedure to facilitate clinical translation. Meanwhile, an easy-to-prepare 68Ga-labeled NOTA-PRGD2 has also been reported to have promising properties for imaging integrin αvβ3. The purpose of this study is to quantitatively compare the pharmacokinetic parameters of [18F]FPPRGD2, [18F]AlF-NOTA-PRGD2, and [68Ga]Ga-NOTA-PRGD2. U87MG tumor-bearing mice underwent 60-min dynamic PET scans following the injection of three tracers. Kinetic parameters were calculated using Logan graphical analysis with reference tissue. Parametric maps were generated using voxel-level modeling. All three compounds showed high binding potential (BpND = k3/k4) in tumor voxels. [18F]AlF-NOTA-PRGD2 showed comparable BpND value (3.75±0.65) with those of [18F]FPPRGD2 (3.39±0.84) and [68Ga]Ga-NOTA-PRGD2 (3.09±0.21) (p>0.05). Little difference was found in volume of distribution (VT) among these three RGD tracers in tumor, liver and muscle. Parametric maps showed similar kinetic parameters for all three tracers. We also demonstrated that the impact of non-specific binding could be eliminated in the kinetic analysis. Consequently, kinetic parameter estimation showed more comparable results among groups than static image analysis. In conclusion, [18F]AlF-NOTA-PRGD2 and [68Ga]Ga-NOTA-PRGD2 have comparable pharmacokinetics and quantitative parameters compared to those of [18F]FPPRGD2. Despite the apparent difference in tumor uptake (%ID/g determined from static images) and clearance pattern, the actual specific binding component extrapolated from kinetic modeling appears to be comparable for all three dimeric RGD tracers

The Mitochondrial Genome of Baylisascaris procyonis

BACKGROUND: Baylisascaris procyonis (Nematoda: Ascaridida), an intestinal nematode of raccoons, is emerging as an important helminthic zoonosis due to serious or fatal larval migrans in animals and humans. Despite its significant veterinary and public health impact, the epidemiology, molecular ecology and population genetics of this parasite remain largely unexplored. Mitochondrial (mt) genomes can provide a foundation for investigations in these areas and assist in the diagnosis and control of B. procyonis. In this study, the first complete mt genome sequence of B. procyonis was determined using a polymerase chain reaction (PCR)-based primer-walking strategy. METHODOLOGY/PRINCIPAL FINDINGS: The circular mt genome (14781 bp) of B. procyonis contained 12 protein-coding, 22 transfer RNA and 2 ribosomal RNA genes congruent with other chromadorean nematodes. Interestingly, the B. procyonis mtDNA featured an extremely long AT-rich region (1375 bp) and a high number of intergenic spacers (17), making it unique compared with other secernentean nematodes characterized to date. Additionally, the entire genome displayed notable levels of AT skew and GC skew. Based on pairwise comparisons and sliding window analysis of mt genes among the available 11 Ascaridida mtDNAs, new primer pairs were designed to amplify specific short fragments of the genes cytb (548 bp fragment) and rrnL (200 bp fragment) in the B. procyonis mtDNA, and tested as possible alternatives to existing mt molecular beacons for Ascaridida. Finally, phylogenetic analysis of mtDNAs provided novel estimates of the interrelationships of Baylisasaris and Ascaridida. CONCLUSIONS/SIGNIFICANCE: The complete mt genome sequence of B. procyonis sequenced here should contribute to molecular diagnostic methods, epidemiological investigations and ecological studies of B. procyonis and other related ascaridoids. The information will be important in refining the phylogenetic relationships within the order Ascaridida and enriching the resource of markers for systematic, population genetic and evolutionary biological studies of parasitic nematodes of socio-economic importance

Cellular therapies for treating pain associated with spinal cord injury

Spinal cord injury leads to immense disability and loss of quality of life in human with no satisfactory clinical cure. Cell-based or cell-related therapies have emerged as promising therapeutic potentials both in regeneration of spinal cord and mitigation of neuropathic pain due to spinal cord injury. This article reviews the various options and their latest developments with an update on their therapeutic potentials and clinical trialing

The role of hSCs in promoting neural differentiation of hUC-MSCs in spinal cord injury

Qiuli Wu,1,* You Chen,1,* Guangzhi Ning,1 Shiqing Feng,1 Junling Han,2 Qiang Wu,1 Yulin LI,1 Hong Wu,1 Hongyu Shi1 1Department of Orthopedics, Tianjin Medical University General Hospital, Tianjin, People's Republic of China; 2Tianjin Union Stem Cell and Gene Engineering Co., Ltd, Tianjin, People's Republic of China * These authors contributed equally to this paper Abstract: Cell therapy is a promising approach to treating spinal cord injury (SCI). Previous studies demonstrated that co-transplantation of human umbilical cord mesenchymal stem cells (hUC-MSCs) and human Schwann cells (hSCs) was an effective strategy by which to promote the regeneration of corticospinal fibers and locomotor recovery after SCI in rats. However, the neural differentiation potential of hUC-MSCs was not fully understood. In the present study, we examined the influence of hSCs on the survival and differentiation of hUC-MSCs in SCI rats. Four groups of rats were implanted with Dulbecco's Modified Eagle's Medium (DMEM), hSCs, hUC-MSCs, or a combination of hSCs and hUC-MSCs, respectively. Our results demonstrated that MAB1281 immunopositive cells appeared in the injured site of the transplanted cell groups, while myelin basic protein and high-molecular-weight neurofilament immunopositive cells were detected only in the co-transplantation group under the positive background of MAB1281. Furthermore, polymerase chain reaction (PCR) and Western blot showed significantly higher expression of myelin basic protein and high-molecular-weight neurofilament and lower expression of glial fibrillary acidic protein in the co-transplantation group (P < 0.05), which correlated strongly with immunofluorescence findings. These results suggest that hSCs could induce hUC-MSC differentiation into neurons and oligodendrocytes and inhibit the formation of glial scarring after SCI. The neural differentiation of hUC-MSCs is likely induced by soluble factors provided by hSCs. Keywords: spinal cord injury, Schwann cell, human umbilical cord mesenchymal stem cell, cell transplantation, neural differentiatio

Incidence and epidemiology of spinal cord injury within a closed American population: the United States military (2000–2009)

The objective of this study was to characterize the incidence of spinal cord injury (SCI) within the population of the United States military from 2000–2009. This investigation also sought to define potential risk factors for the development of SCI