Nano magnetite-loaded biochar boosted methanogenesis through shifting microbial community composition and modulating electron transfer.

A batch anaerobic fermentation system was employed to clarify how nano magnetite-loaded biochar can improve methanogenic performance of the propionate-degrading consortia (PDC). The nano magnetite-loaded biochar was prepared in a sequential hydrothermal and pyrolysis procedure using the household waste (HW), biogas residue (BR) and Fe (NO3)3 as pristine materials. Comprehensive characterization showed that the nano magnetite-loaded biochar ameliorated the biochar properties with large specific surface area, high electrochemical response and low electron transfer resistance. PDC supplemented with the magnetite/BR-originated biochar composites displayed excellent methanogenic performance, where the methane production rate was enhanced by 1.6-fold compared with the control. The nano magnetite-loaded biochar promoted methane production probably by promoting direct interspecies electron transfer between syntrophic bacteria (e.g., Syntrophobacter and Thauera) and their partners (e.g., Methanosaeta). In this process, magnetite might be responsible for triggering rapidly extracellular electron release, whereas both external functional groups and intrinsic graphitic matrices of biochar might work as electron bridges for electron transport.

Food availability on the shore: Linking epilithic and planktonic microalgae to the food ingested by two intertidal gastropods.

Research on the interaction of primary producers and consumers is crucial for understanding trophic transfer in intertidal food webs. This study explores the association between epilithic and planktonic microalgae, and gut contents of two targeted intertidal gastropods, the periwinkle Echinolittorina radiata (splash zone) and the limpet Cellana toreuma (mid-intertidal zone). With the application of gut fluorescence technique and metabarcoding, this study investigates the quantity and composition of two different sources of microalgae (epilithic and planktonic) and the food ingested by the gastropods. The results suggest the following findings: 1) The planktonic microalgae have higher compositional similarity to the gut contents of grazing gastropods. 2) Increased gut pigment content in C. toreuma is observed with increasing abundance of epilithic and planktonic microalgae. However, there was no such pattern observed for E. radiata. This difference could be attributed to potentially divergent foraging behaviours of the two species that inhabit different shore heights.

Characterization of the complete mitochondrial genome of Coelastrum_sp.F187.

Coelastrum is a genus of green algae that belongs to the Scenedesmaceae family. There is little information available about this genus. A phylogenetic analysis of the ITS2 sequences showed that Coelastrum is a paraphyletic group. To better explore the phylogenetic status of this genus, we report the mitochondrial genome sequence of Coelastrum sp. F187 using next-generation sequencing technology. The complete mitochondrial genome is 52,888 bp in size and encodes 43 conventional mitochondrial genes, including 14 protein-coding genes (PCGs), 24 transfer RNA (tRNA) genes, and four ribosomal RNA (rRNA) genes. Most of the PCGs (12/14) and all tRNAs were located in the heavy chain and the light chain, respectively. The phylogenetic analysis based on the complete mitochondrial genome sequences indicated that Coelastrum is closely related to Pectinodesmus pectinatus. The sequenced complete mitochondrial genome of Coelastrum sp. F187 provides fundamental molecular data that will be useful for species identification, population genetics, and evolutionary relationships.

PTEN status is related to cell proliferation and self-renewal independent of CD133 phenotype in the glioma-initiating cells.

CD133 is extensively used as a surface marker to identify and isolate glioma-initiating cells (GICs) from malignant brain tumors; however, instances of CD133(-) cells exhibiting similar properties have also been reported. To clarify the availability of CD133 as the GIC marker, we first evaluated the ratio of CD133(+) cells and malignancy of glioma spheroids GIC1 and GIC2, respectively. GIC1, which showed a lower percentage of CD133(+) cells, exhibited a highly aggressive behavior in comparison with GIC2. The following experiments demonstrated that tumor suppressor PTEN was lost in GIC1, resulting in the activation of AKT pathway. Overexpression of recombinant PTEN in GIC1 suppressed its proliferation and self-renew without significant effect on CD133 expression level, indicating that the inconsistence between the ratio of CD133(+) cells and proliferation and self-renewal capacity of GIC1 and GIC2 was caused by PTEN deficiency. To further validate our conclusion, a series of GICs were analyzed and the percentages of CD133(+) cells could not reflect the degrees of cell proliferation and self-renewal characteristics in the PTEN deficient GICs, suggesting that the application of CD133 as the GIC maker was restricted by PTEN loss. Furthermore, down-regulation of PTEN in the PTEN-expressing GICs could break the positive correlation between the ratio of CD133(+) cells and proliferation and self-renewal capacity. Our results demonstrated that PTEN status is related to cell proliferation and self-renewal independent of CD133 phenotype in the glioma-initiating cells, resulting in the limitations of CD133 as a biomarker for PTEN deficient GICs.

[Study on vitrification of porcine embryos by open pulled straw method].

291 embryos (Blastocyst/Morula) from 20 donor sows were vitrified by two step method with OPS (open pulled straw) in solution I (TCM199 + 20% FBS + 10% EG + 10% DMSO) for 3min, and solution II (TCM199 + 20% FBS + 20% EG + 20% DMSO + 0.4mol/L SUC) for 1min, stored in liquid nitrogen for 3 months, and transferred into 8 recipient sows after warming, one recipient sow was pregnant and 8 alive piglets were born. This is the first paper to report getting alive piglets by vitrification in China.