B lymphocyte regulation of human hematopoiesis

Epstein Barr virus (EBV)-transformed B lymphoblastoid cell lines (BLCL) were derived from seven different individuals. The ability of BLCL supernatants to stimulate hematopoietic colony formation in vitro was tested in a conventional stem cell assay system. Supernatants promoted the growth of single (GM, E, MK) as well as multi-lineage (GEMM) colonies in bone marrow cultures. Our results indicate that EBV-transformed B lymphocytes produce cytokines that affect in vitro stem cell proliferation and differentiation. These studies demonstrate the regulatory potential of activated B lymphocytes in human hematopoiesis.     

Elevated acetyl‐CoA by amino acid recycling fuels microalgal neutral lipid accumulation in exponential growth phase for biofuel production

Microalgal neutral lipids [mainly in the form of triacylglycerols (TAGs)], feasible substrates for biofuel, are typically accumulated during the stationary growth phase. To make microalgal biofuels economically competitive with fossil fuels, generating strains that trigger TAG accumulation from the exponential growth phase is a promising biological approach. The regulatory mechanisms to trigger TAG accumulation from the exponential growth phase (TAEP) are important to be uncovered for advancing economic feasibility. Through the inhibition of pyruvate dehydrogenase kinase by sodium dichloroacetate, acetyl‐CoA level increased, resulting in TAEP in microalga Dunaliella tertiolecta. We further reported refilling of acetyl‐CoA pool through branched‐chain amino acid catabolism contributed to an overall sixfold TAEP with marginal compromise (4%) on growth in a TAG‐rich D. tertiolecta mutant from targeted screening. Herein, a three‐step α loop‐integrated metabolic model is introduced to shed lights on the neutral lipid regulatory mechanism. This article provides novel approaches to compress lipid production phase and heightens lipid productivity and photosynthetic carbon capture via enhancing acetyl‐CoA level, which would optimize renewable microalgal biofuel to fulfil the demanding fuel market.     

Properties and Expression of Na+/K+-ATPase α-Subunit Isoforms in the Brain of the Swamp Eel,Monopterus albus,Which Has Unusually High Brain Ammonia Tolerance

The swamp eel, Monopterus albus, can survive in high concentrations of ammonia (>75 mmol l⁻¹) and accumulate ammonia to high concentrations in its brain (∼4.5 µmol g⁻¹). Na⁺/K⁺-ATPase (Nka) is an essential transporter in brain cells, and since NH₄ ⁺ can substitute for K⁺ to activate Nka, we hypothesized that the brain of M. albus expressed multiple forms of Nka α-subunits, some of which might have high K⁺ specificity. Thus, this study aimed to clone and sequence the nka α-subunits from the brain of M. albus, and to determine the effects of ammonia exposure on their mRNA expression and overall protein abundance. The effectiveness of NH₄ ⁺ to activate brain Nka from M. albus and Mus musculus was also examined by comparing their Na⁺/K⁺-ATPase and Na⁺/NH₄ ⁺-ATPase activities over a range of K⁺/NH₄ ⁺ concentrations. The full length cDNA coding sequences of three nkaα (nkaα1, nkaα3a and nkaα3b) were identified in the brain of M. albus, but nkaα2 expression was undetectable. Exposure to 50 mmol l⁻¹ NH₄Cl for 1 day or 6 days resulted in significant decreases in the mRNA expression of nkaα1, nkaα3a and nkaα3b. The overall Nka protein abundance also decreased significantly after 6 days of ammonia exposure. For M. albus, brain Na⁺/NH₄ ⁺-ATPase activities were significantly lower than the Na⁺/K⁺-ATPase activities assayed at various NH₄ ⁺/K⁺ concentrations. Furthermore, the effectiveness of NH₄ ⁺ to activate Nka from the brain of M. albus was significantly lower than that from the brain of M. musculus, which is ammonia-sensitive. Hence, the (1) lack of nkaα2 expression, (2) high K⁺ specificity of K⁺ binding sites of Nkaα1, Nkaα3a and Nkaα3b, and (3) down-regulation of mRNA expression of all three nkaα isoforms and the overall Nka protein abundance in response to ammonia exposure might be some of the contributing factors to the high brain ammonia tolerance in M. albus.     

Stage-specific mortality of Rhagoletis indifferens (Diptera: Tephritidae) exposed to three species of Steinernema nematodes

Mortality of larval, pupal, and adult western cherry fruit fly, Rhagoletis indifferens (Tephritidae) exposed to the steinernematid nematodes Steinernema carpocapsae, Steinernema feltiae, and Steinernema intermedium, was determined in the laboratory and field. Larvae were the most susceptible stage, with mortality in the three nematode treatments ranging from 62 to 100%. S. carpocapsae and S. feltiae were equally effective against larvae at both 50 and 100 infective juveniles (IJs)/cm². S. intermedium was slightly less effective against larvae than the other two species. Mortalities of R. indifferens larvae at 0, 2, 4, and 6 days following their introduction into soil previously treated with S. carpocapsae and S. feltiae at 50 IJs/cm² were 78.6, 92.5, 95.0, and 77.5% and 87.5, 52.5, 92.5, and 70.0%, respectively, and at 100 IJs/cm² were 90.0, 92.0, 100.0, and 84.0% and 90.0, 50.0, 42.0, and 40.0%, respectively. There was no decline in mortality caused by S. carpocapsae as time progressed, whereas there was in one test with S. feltiae. Larval mortalities caused by the two species were the same in a 1:1:1 vermiculite:peat moss:sand soil mix and a more compact silt loam soil. In the field, S. carpocapsae and S. feltiae were equally effective against larvae. Pupae were not infected, but adult flies were infected by all three nematode species in the laboratory. S. carpocapsae was the most effective species at a concentration of 100 IJs/cm² and infected 11–53% of adults that emerged. The high pathogenicity of S. carpocapsae and S. feltiae against R. indifferens larvae and their persistence in soil as well as efficacy in different soil types indicate both nematodes hold promise as effective biological control agents of flies in isolated and abandoned lots or in yards of homeowners.     

A general framework for propagule dispersal in mangroves

Dispersal allows species to shift their distributions in response to changing climate conditions. As a result, dispersal is considered a key process contributing to a species' long‐term persistence. For many passive dispersers, fluid dynamics of wind and water fuel these movements and different species have developed remarkable adaptations for utilizing this energy to reach and colonize suitable habitats. The seafaring propagules (fruits and seeds) of mangroves represent an excellent example of such passive dispersal. Mangroves are halophytic woody plants that grow in the intertidal zones along tropical and subtropical shorelines and produce hydrochorous propagules with high dispersal potential. This results in exceptionally large coastal ranges across vast expanses of ocean and allows species to shift geographically and track the conditions to which they are adapted. This is particularly relevant given the challenges presented by rapid sea‐level rise, higher frequency and intensity of storms, and changes in regional precipitation and temperature regimes. However, despite its importance, the underlying drivers of mangrove dispersal have typically been studied in isolation, and a conceptual synthesis of mangrove oceanic dispersal across spatial scales is lacking. Here, we review current knowledge on mangrove propagule dispersal across the various stages of the dispersal process. Using a general framework, we outline the mechanisms and ecological processes that are known to modulate the spatial patterns of mangrove dispersal. We show that important dispersal factors remain understudied and that adequate empirical data on the determinants of dispersal are missing for most mangrove species. This review particularly aims to provide a baseline for developing future research agendas and field campaigns, filling current knowledge gaps and increasing our understanding of the processes that shape global mangrove distributions.     

Effects of substerilizing doses of gamma radiation on adult longevity and level of inherited sterility in Teia anartoides (Lepidoptera: Lymantriidae)

The effects of substerilizing doses of gamma radiation on the longevity and level of inherited sterility in the Australian moth Teia anartoides Walker were determined. Six day-old male pupae were treated with 0, 100, and 160 Gy of gamma radiation by using a 1.25 MeV Cobalt60 irradiation source. Laboratory studies of male longevity showed that radiation had little impact in adult moths of the P1, F1, and F2 generations. Inherited deleterious effects resulting from irradiation were observed in the progeny of F1 and F2 generations. Outcrosses between substerile parental males or their highly sterile male progeny to wild-type females did not affect female fecundity. However, adverse effects were observed for these crosses in the rates of successful egg hatch and postembryonic development. Fertility was always greater in out-crosses involving a P1 male than in any of the F1 out-crosses. F1 males were always more sterile than F1 females, and the level of sterility for the F1 and F2 generations was higher than that of the controls. The incidence of larval and pupal mortality was higher in the F2 than the F1 generation. A dose of 100 Gy had the highest success in inducing deleterious effects that were inherited through to the F2 generation. Our results indicated that the use of partially sterilizing doses of radiation has good potential as a selective strategy for management or eradication of T. anartoides.     

Unveiling The Mechanism of The Dendrite Nucleation and Growth in Aqueous Zinc Ion Batteries

Aqueous zinc ion batteries (ZIBs) exhibit great potential for next-generation energy storage devices. However, significant challenges exist, including the uncontrollable formation of Zn dendrite and side reactions during zinc stripping and plating. The mechanism of Zn dendrite nucleation has yet to be fully understood. In this work, the first principles simulations are used to investigate the Zn dendrite formation process. The unintentionally adsorbed O²⁻ and OH⁻ ions are the inducing factors for Zn dendrite nucleation and growth on the Zn (0001) plane due to significantly increased Zn diffusion barriers. A top-down method is demonstrated to suppress the dendrite using delaminated V₂CT_x to capture O²⁻ and OH⁻ ions thanks to reduced Zn diffusion barriers. The experimental results revealed significantly suppressed Zn dendrite nucleation and growth, resulting in a layer-by-layer deposit/stripping of Zn. Based on the electrochemical evaluations, the V₂CT_x-coated Zn composite delivers a high coulombic efficiency of 99.3% at 1.0 mAh cm⁻². Furthermore, the full cell achieves excellent cyclic performance of 93.6% capacity retention after 2000 cycles at 1 A g⁻¹. This strategy has broad scalability and can be widely applied in designing metallic anodes for rechargeable batteries.     

Rethinking the evolution of extant sub‐Saharan African suids (Suidae,Artiodactyla)

Gongora, J., Cuddahee, R. E., do Nascimento, F. F., Palgrave, C. J., Lowden, S., Ho, S. Y. W., Simond, D., Damayanti, C. S., White, D. J., Tay, W. T., Randi, E., Klingel, H., Rodrigues‐Zarate, C. J., Allen, K., Moran, C. & Larson, G. (2011). Rethinking the evolution of extant sub‐Saharan African suids (Suidae, Artiodactyla). —Zoologica Scripta, 40, 327–335. Although African suids have been of scientific interest for over two centuries, their origin, evolution, phylogeography and phylogenetic relationships remain contentious. There has been a long‐running debate concerning the evolution of pigs and hogs (Suidae), particularly regarding the phylogenetic relationships among extant Eurasian and African species of the subfamily Suinae. To investigate these issues, we analysed the mitochondrial and nuclear DNA sequences of extant genera of Suidae from Eurasia and Africa. Molecular phylogenetic analyses revealed that all extant sub‐Saharan African genera form a monophyletic clade separate from Eurasian suid genera, contradicting previous attempts to resolve the Suidae phylogeny. Two major sub‐Saharan African clades were identified, with Hylochoerus and Phacochoerus grouping together as a sister clade to Potamochoerus. In addition, we find that the ancestors of extant African suids may have evolved separately from the ancestors of modern day Sus and Porcula in Eurasia before they colonised Africa. Our results provide a revision of the intergeneric relationships within the family Suidae.     

Recovery of Corneal Endothelial Cells from Periphery after Injury

Background

Wound healing of the endothelium occurs through cell enlargement and migration. However, the peripheral corneal endothelium may act as a cell resource for the recovery of corneal endothelium in endothelial injury.

Aim

To investigate the recovery process of corneal endothelial cells (CECs) from corneal endothelial injury.

Methods

Three patients with unilateral chemical eye injuries, and 15 rabbit eyes with corneal endothelial chemical injuries were studied. Slit lamp examination, specular microscopy, and ultrasound pachymetry were performed immediately after chemical injury and 1, 3, 6, and 9 months later. The anterior chambers of eyes from New Zealand white rabbits were injected with 0.1 mL of 0.05 N NaOH for 10 min (NaOH group). Corneal edema was evaluated at day 1, 7, and 14. Vital staining was performed using alizarin red and trypan blue.

Results

Specular microscopy did not reveal any corneal endothelial cells immediately after injury. Corneal edema subsided from the periphery to the center, CEC density increased, and central corneal thickness decreased over time. In the animal study, corneal edema was greater in the NaOH group compared to the control at both day 1 and day 7. At day 1, no CECs were detected at the center and periphery of the corneas in the NaOH group. Two weeks after injury, small, hexagonal CECs were detected in peripheral cornea, while CECs in mid-periphery were large and non-hexagonal.

Conclusions

CECs migrated from the periphery to the center of the cornea after endothelial injury. The peripheral corneal endothelium may act as a cell resource for the recovery of corneal endothelium.