Search

To assess the optimal dietary protein requirement of adult red swamp crayfish (Procambarus clarkii) farming in the rice field, six isoenergetic and isolipid diets were formulated to contain graded levels of 28%, 31%, 34%, 37%, 40% and 43% crude protein (called Diet 28–43 group). Each diet was assigned to a triplicate of 20 experimental crayfish with the average initial body weight of (15.17 ± 0.23) g for 42 days. Our results showed that the final body weight, weight gain rate and specific growth rate of red swamp crayfish adult in the Diet 34, Diet 37, Diet 40 and Diet 43 groups were significantly higher than those of other groups (P 0.05). Activities of trypsin and lipase in the intestine were significantly affected by dietary protein levels (P 0.05). Moreover, higher dietary protein significantly increased the antioxidant and non-specific immunity enzyme activity. Broken-line regression analysis based on weight gain rate and specific growth rate showed that the optimal dietary protein level for maximum growth performance of crayfish was 32.68%. According to the present study on the growth performance, the muscle of Diet 28 group (SM) and Diet 34 group (LM) individuals were selected for transcriptome sequencing. The results showed that there were 444 differential genes in SM and LM, of which 282 genes were up-regulated and 162 genes were down-regulated. DEGs of SM and LM groups differential genes were mainly enriched in citrate cycle, pyruvate cycle, glycolysis/gluconeogenesis, etc. Beyond that, transcriptomic results also hinted that glycolysis/gluconeogenesis and citrate cycle signaling pathways might be its growth change mechanisms. In addition, the aldo, eno, pk, pdhb, adh, sdha, fh, mdh2, cs were also identified as the key factors involved in glycolysis/gluconeogenesis and citrate cycle pathways. In conclusion, combining growth performance and transcriptome data, we recommended that diets with 32.68%− 34.00% protein were optimal for red swamp crayfish in the rice-shrimp farming pattern.

Summary: Precursors of hematopoietic stem cells (pre-HSCs) have been identified as intermediate precursors during the maturation process from hemogenic endothelial cells to HSCs in the aorta-gonad-mesonephros (AGM) region of the mouse embryo at embryonic day 10.5. Although pre-HSCs acquire an efficient adult-repopulating ability after ex vivo co-culture, their native hematopoietic capacity remains unknown. Here, we employed direct transplantation assays of CD45−VE-cadherin(VC)+KIT+(V+K+) cells (containing pre-HSCs) into immunodeficient neonatal mice that permit engraftment of embryonic hematopoietic precursors. We found that freshly isolated V+K+ cells exhibited significantly greater B-1 lymphocyte-biased repopulating capacity than multilineage repopulating capacity. Additionally, B cell colony-forming assays demonstrated the predominant B-1 progenitor colony-forming ability of these cells; however, increased B-2 progenitor colony-forming ability emerged after co-culture with Akt-expressing AGM endothelial cells, conditions that support pre-HSC maturation into HSCs. Our studies revealed an unexpected B-1 lymphocyte bias of the V+K+ population and acquisition of B-2 potential during commitment to the HSC fate. : Yoshimoto and colleagues demonstrate an unexpected inherent B-1-biased repopulation ability of E10.5 pre-HSCs in immunodeficient neonatal mice. The B-1-biased pre-HSCs acquire B-2 potential following ex vivo co-culture, reflecting the developmental process of hemogenic endothelial cells to HSCs through B-1-biased state in vivo. Notably, the E10.5 pre-HSCs are the first B-1a repopulating cells upon direct transplantation without co-culture. Keywords: mouse embryos, hematopoietic stem cells (HSCs), pre-HSC, AGM, B-1a cells, hemogenic endothelial cells

As a potentially unlimited autologous cell source, patient induced pluripotent stem cells (iPSCs) provide great capability for tissue regeneration, particularly in spinal cord injury (SCI). However, despite significant progress made in translation of iPSC-derived neural progenitor cells (NPCs) to clinical settings, a few hurdles remain. Among them, non-invasive approach to obtain source cells in a timely manner, safer integration-free delivery of reprogramming factors, and purification of NPCs before transplantation are top priorities to overcome. In this study, we developed a safe and cost-effective pipeline to generate clinically relevant NPCs. We first isolated cells from patients' urine and reprogrammed them into iPSCs by non-integrating Sendai viral vectors, and carried out experiments on neural differentiation. NPCs were purified by A2B5, an antibody specifically recognizing a glycoganglioside on the cell surface of neural lineage cells, via fluorescence activated cell sorting. Upon further in vitro induction, NPCs were able to give rise to neurons, oligodendrocytes and astrocytes. To test the functionality of the A2B5+ NPCs, we grafted them into the contused mouse thoracic spinal cord. Eight weeks after transplantation, the grafted cells survived, integrated into the injured spinal cord, and differentiated into neurons and glia. Our specific focus on cell source, reprogramming, differentiation and purification method purposely addresses timing and safety issues of transplantation to SCI models. It is our belief that this work takes one step closer on using human iPSC derivatives to SCI clinical settings.