Transplantation of a Peripheral Nerve with Neural Stem Cells Plus Lithium Chloride Injection Promote the Recovery of Rat Spinal Cord Injury

Transplantation of neural stem cells (NSCs) holds great potential for the treatment of spinal cord injury (SCI). However, transplanted NSCs poorly survive in the SCI environment. We injected NSCs into tibial nerve and transplanted tibial nerve into a hemisected spinal cord and investigated the effects of lithium chloride (LiCl) on the survival of spinal neurons, axonal regeneration, and functional recovery. Our results show that most of the transplanted NSCs expressed glial fibrillary acidic protein, while there was no obvious expression of nestin, neuronal nuclei, or acetyltransferase found in NSCs. LiCl treatment produced less macrosialin (ED1) expression and axonal degeneration in tibial nerve after NSC injection. Our results also show that a regimen of LiCl treatment promoted NSC differentiation into NF200-positive neurons with neurite extension into the host spinal cord. The combination of tibial nerve transplantation with NSCs and LiCl injection resulted in more host motoneurons surviving in the spinal cord, more regenerated axons in tibial nerve, less glial scar area, and decreased ED1 expression. We conclude that lithium may have therapeutic potential in cell replacement strategies for central nervous system injury due to its ability to promote survival and neuronal generation of grafted NSCs and reduced host immune reaction

Pathogen-origin horizontally transferred genes contribute to the evolution of Lepidopteran insects

<p>Abstract</p> <p>Background</p> <p>Horizontal gene transfer (HGT), a source of genetic variation, is generally considered to facilitate hosts' adaptability to environments. However, convincing evidence supporting the significant contribution of the transferred genes to the evolution of metazoan recipients is rare.</p> <p>Results</p> <p>In this study, based on sequence data accumulated to date, we used a unified method consisting of similarity search and phylogenetic analysis to detect horizontally transferred genes (HTGs) between prokaryotes and five insect species including <it>Drosophila melanogaster</it>, <it>Anopheles gambiae</it>, <it>Bombyx mori</it>, <it>Tribolium castaneum </it>and <it>Apis mellifera</it>. Unexpectedly, the candidate HTGs were not detected in <it>D. melanogaster</it>, <it>An. gambiae </it>and <it>T. castaneum</it>, and 79 genes in <it>Ap. mellifera </it>sieved by the same method were considered as contamination based on other information. Consequently, 14 types of 22 HTGs were detected only in the silkworm. Additionally, 13 types of the detected silkworm HTGs share homologous sequences in species of other Lepidopteran superfamilies, suggesting that the majority of these HTGs were derived from ancient transfer events before the radiation of Ditrysia clade. On the basis of phylogenetic topologies and BLAST search results, donor bacteria of these genes were inferred, respectively. At least half of the predicted donor organisms may be entomopathogenic bacteria. The predicted biochemical functions of these genes include four categories: glycosyl hydrolase family, oxidoreductase family, amino acid metabolism, and others.</p> <p>Conclusions</p> <p>The products of HTGs detected in this study may take part in comprehensive physiological metabolism. These genes potentially contributed to functional innovation and adaptability of Lepidopteran hosts in their ancient lineages associated with the diversification of angiosperms. Importantly, our results imply that pathogens may be advantageous to the subsistence and prosperity of hosts through effective HGT events at a large evolutionary scale.</p

A new species of Polycelis (Platyhelminthes, Tricladida, Planariidae) from China

In this paper, a new species of Polycelis of the family Planariidae from China is described. Mature individuals have 80–140 eyespots; the testes are well-developed and most of them occupy the entire dorso-ventral space; the penis is a long cone with well-developed musculature; the boundary between the penis bulb and penis papilla is vague and the bulbar cavity is not observed; the bursal canal is surrounded by a well-developed coat of circular muscles, and a thin layer of longitudinal muscles. The karyotype shows a diploid complement of 38 chromosomes, with the formula 2n = 38 = 24m + 14sm