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61.
Background aimsSeveral studies have reported functional improvement after transplantation of in vivo-derived neural progenitor cells (NPC) into injured spinal cord. However, the potential of human embryonic stem cell-derived NPC (hESC-NPC) as a tool for cell replacement of spinal cord injury (SCI) should be considered.MethodsWe report on the generation of NPC as neural-like tubes in adherent and feeder-free hESC using a defined media supplemented with growth factors, and their transplantation in collagen scaffolds in adult rats subjected to midline lateral hemisection SCI.ResultshESC-NPC were highly expressed molecular features of NPC such as Nestin, Sox1 and Pax6. Furthermore, these cells exhibited the multipotential characteristic of differentiating into neurons and glials in vitro. Implantation of xenografted hESC-NPC into the spinal cord with collagen scaffold improved the recovery of hindlimb locomotor function and sensory responses in an adult rat model of SCI. Analysis of transplanted cells showed migration toward the spinal cord and both neural and glial differentiation in vivo.ConclusionsThese findings show that transplantation of hESC-NPC in collagen scaffolds into an injured spinal cord may provide a new approach to SCI.  相似文献   
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Trichoderma brevicompactum, a new species, was isolated from soil or tree bark in North, Central and South America, including the Caribbean Islands, and southwestern and southeastern Asia. Morphological and physiological characters, the internal transcribed spacer regions of the rDNA cluster (ITS1-5.8SrDNA-ITS2) and partial sequences of translation elongation factor 1-alpha (tef1) are described. Trichoderma brevicompactum is characterized by a pachybasium-type morphology, morphologically resembling other small-spored species referable to Trichoderma section Pachybasium but with essentially subglobose conidia. It is most closely related phylogenetically to Hypocrea lutea, from which it differs in morphological and physiological characters.  相似文献   
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Russian Journal of Bioorganic Chemistry - Fe3O4@SiO2–Pr@L-proline magnetic nanoparticles were synthesized and their efficiency as nanocatalyst for the synthesis of new derivatives of bis...  相似文献   
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Chlorobaculum [Cba.] tepidum is known to grow optimally at 48–52 °C and can also be cultured at ambient temperatures. In this paper, we prepared constant temperature, temperature shift, and temperature shift followed by backshift cultures and investigated the intrinsic properties and spectral features of chlorosomes from those cultures using various approaches, including temperature-dependent measurements on circular dichroism (CD), UV–visible, and dynamic light scattering. Our studies indicate that (1) chlorosomes from constant temperature cultures at 50 and 30 °C exhibited more resistance to heat relative to temperature shift cultures; (2) as temperature increases bacteriochlorophyll c (BChl c) in chlorosomes is prone to demetalation, which forms bacteriopheophytin c, and degradation under aerobic conditions. Some BChl c aggregates inside reduced chlorosomes prepared in low-oxygen environments can reform after heat treatments; (3) temperature shift cultures synthesize and incorporate more BChl c homologs with a smaller substituent at C-8 on the chlorin ring and less BChl c homologs with a larger long-chain alcohol at C-173 versus constant-temperature cultures. We hypothesize that the long-chain alcohol at C-173 (and perhaps together with the substituent at C-8) may account for thermal stability of chlorosomes and the substituent at C-8 may assist self-assembling BChls; and (4) while almost identical absorption spectra are detected, chlorosomes from different growth conditions exhibited differences in the rotational length of the CD signal, and aerobic and reduced chlorosomes also display different Qy CD intensities. Further, chlorosomes exhibited changes of CD features in response to temperature increases. Additionally, we compare temperature-dependent studies for the Cba. tepidum chlorosomes and previous studies for the Chloroflexus aurantiacus chlorosomes. Together, our work provides useful and novel insights on the properties and organization of chlorosomes.  相似文献   
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Length–weight parameters were estimated for 37 freshwater fish species of Iran belonging to seven families. Significant length–weight relationships with high correlation coefficients were found for all species.  相似文献   
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Russian Journal of Bioorganic Chemistry - An efficient, green and new avenue for the synthesis of novel derivatives of pyrano[3,2-c]chromene-diones using the reaction between aldehydes,...  相似文献   
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