Isolation, genome analysis and comparison of a novel parainfluenza virus 5 from a Siberian tiger (Panthera tigris).

Paramyxoviruses are important pathogens affecting various animals, including mammals and humans. Parainfluenza virus 5 (PIV5)-a member of the family Paramyxoviridae-is a major threat to the health of mammals and humans. However, studies on terrestrial wild animals infected with PIV5 are scanty. In this study, we utilized reverse transcription PCR to detect PIV5 infection in the visceral organ tissues of a Siberian tiger (Panthera tigris ssp. altaica) with vomiting, diarrhea, and dyspnea before its death. A novel PIV5 (named SR strain) with a slowly progressive cytopathic effect was isolated in Vero cells and validated using a transmission electron microscope. Full-length sequencing and analysis revealed that the whole genome of the PIV5 SR strain contained 15,246 nucleotides (nt) and seven non-overlapping genes (3'-N-V/P-M-F-SH-HN-L-5') encoding eight proteins. Phylogenetic analysis of three PIV5 strains identified in the same zoo confirmed that PIV5 strains SR and ZJQ-221 shared the closest genetic relationship as they were clustered in the same branch, while the recently found Siberian tiger strain SZ2 kept a certain distance and formed a relatively unique branch. Furthermore, mutations of nt and amino acids (aa) between strains ZJQ-221, SR, and SZ2 were identified. In summary, we report the identification and genomic characterization of a novel PIV5 strain SR isolated in a Siberian tiger, which may help future research on interspecific transmission mechanisms.

Fabrication of ultra-stable and high-efficient CoP-based electrode toward seawater splitting at industrial-grade current density.

The mild and rapid construction of economical, efficient and ultrastable electrodes for hydrogen production via water splitting at industrial-grade current density remains extremely challenging. Herein, a one-step mild electroless plating method is proposed to deposit cobalt phosphorus (CoP)-based species on robust nickel net (NN, denoted as Co-P@NN). The tight interfacial contact, corrosion-proof self-supporting substrate and synergistic effect of Co-P@Co-O contribute greatly to the rapid electron transport, high intrinsic activity and long-term durability in the alkaline simulated seawater (1.0 M KOH + 0.5 M NaCl). Attractively, Co-P@Co-O also achieves ultrastable catalysis for over 2880 h with negligible activity attenuation under various alkaline extreme conditions (simulated seawater, high-salt environment, domestic sewage and so on). Furthermore, this work successfully constructs a series of ternary elemental doped (Ni, S, B, Fe and so on) CoP-based catalytic electrodes for highly efficient overall seawater splitting (OSWS). This work demonstrates not only an ideal platform for the versatile strategy of mildly obtaining CoP-based electrocatalysts but also the pioneering philosophy of large-scale hydrogen production.

Mild construction of an Fe-B-O based flexible electrode toward highly efficient alkaline simulated seawater splitting.

It is essential to construct self-supporting electrodes based on earth-abundant iron borides in a mild and economical manner for grid-scale hydrogen production. Herein, a series of highly efficient, flexible, robust, and scalable Fe-B-O@FeBx modified on hydrophilic cloth (denoted as Fe-B-O@FeBx/HC, 10 cm × 10 cm) are fabricated by mild electroless plating. The overpotentials and Tafel slope values for the hydrogen and oxygen evolution reactions are 59 mV and 57.62 mV dec-1 and 181 mV and 65.44 mV dec-1, respectively; only 1.462 V is required to achieve 10 mA cm-2 during overall water splitting (OWS). Fe-B-O@FeBx/HC maintains its high catalytic activity for more than 7 days at an industrial current density (400 mA cm-2), owing to the loosened popcorn-like Fe-B-O@FeBx that is firmly loaded on a 2D-layered and mechanically robust substrate along with its fast charge and mass transfer kinetics. The chimney effect of core-shell borides@(oxyhydro)oxides enhances the OWS performance and protects the inner metal borides from further corrosion. Moreover, the flexible Fe-B-O@FeBx/HC electrode has a low cost for grid-scale hydrogen production ($2.97 kg-1). The proposed strategy lays a solid foundation for universal preparation, large-scale hydrogen production and practical applications thereof.

Fabrication of Ultra-Durable and Flexible NiPx -Based Electrode toward High-Efficient Alkaline Seawater Splitting at Industrial Grade Current Density.

Designing nonprecious metal-based electrocatalysts to yield sustainable hydrogen energy by large-scale seawater electrolysis is challenging to global emissions of carbon neutrality and carbon peaking. Herein, a series of highly efficient, economical, and robust Ni-P-based nanoballs grown on the flexible and anti-corrosive hydrophobic asbestos (NiPx @HA) is synthesized by electroless plating at 25 °C toward alkaline simulated seawater splitting. On the basis of the strong chemical attachment between 2D layered substrate and nickel-rich components, robust hexagonal Ni5 P4 crystalline modification, and fast electron transfer capability, the overpotentials during hydrogen/oxygen evolution reaction (HER/OER) are 208 and 392 mV at 200 mA cm-2 , and the chronopotentiometric measurement at 500 mA cm-2 lasts for over 40 days. Additionally, the versatile strategy is broadly profitable for industrial applications and enables multi-elemental doping (iron/cobalt/molybdenum/boron/tungsten), flexible substrate employment (nickel foam/filter paper/hydrophilic cloth), and scalable synthesis (22 cm × 22 cm). Density functional theory (DFT) also reveals that the optimized performance is due to the fundamental effect of incorporating O-source into Ni5 P4 . Therefore, this work exhibits a complementary strategy in the construction of NiPx -based electrodes and offers bright opportunities to produce scalable hydrogen effectively and stably in alkaline corrosive electrolytes.

Mild Construction of "Midas Touch" Metal-Organic Framework-Based Catalytic Electrodes for Highly Efficient Overall Seawater Splitting.

Mild construction of highly efficient and durable practical electrodes for overall water splitting (OWS) at industrial-grade current density is currently a significant challenge. Herein, metal-organic framework (MOF) materials are grown in situ on the surface of carbon cloth (CC) at 25 °C, and quickly "interspersed" by cobalt-boron (Co-B) via electroless plating for 30 min to obtain a highly efficient and stable CoB@MOF@CC self-supporting electrode. Owing to the large specific surface area, abundant active sites, and porous structure, the MOF-based CC modified by bamboo leaf-like ultrathin CoB has remarkable electrochemical catalysis efficiency. The CoB@MOF@CC electrode exhibits excellent performance during the hydrogen evolution reaction (η10  = 57 mV, η500  = 266 mV) and oxygen evolution reaction (η10  = 209 mV, η500  = 423 mV) in alkaline simulated seawater, and is durable for 2500 h at 500 mA cm-2 . The OWS performance is obviously enhanced by employing the prepared electrode, which only requires 1.49 V to achieve 10 mA cm-2 and is durable for over 360 h at industrial-grade current densities in alkaline high-salt, real seawater, rainwater, and urea electrolytes.

Sulfur doped FeOx nanosheet arrays supported on nickel foam for efficient alkaline seawater splitting.

Developing economical, efficient and stable bifunctional catalysts for hydrogen production from seawater is of great significance for hydrogen utilization. Herein, sulfur doped iron oxide nanosheet arrays supported on nickel foam (FeOx-Ni3S2@NF) are prepared by a one-pot solvothermal reaction. Owing to the high intrinsic activity of FeOx-Ni3S2, the large catalytic specific surface area of nanosheet arrays and the fast charge transportation capability achieved by the self-supporting configuration, the FeOx-Ni3S2@NF electrode delivers excellent catalytic performance in alkaline simulated seawater (1 M KOH + 0.5 M NaCl). Impressively, a low overpotential of 120 mV at 50 mA cm-2 with a Tafel slope of 57 mV dec-1 for the hydrogen evolution reaction and an overpotential of 470 mV at 200 mA cm-2 with a Tafel slope of 62 mV dec-1 for the oxygen evolution reaction are achieved. More importantly, the voltage is only 1.5 V at 50 mA cm-2 for continuous overall water splitting for 100 h at 200 mA cm-2 with negligible decay in alkaline simulated seawater with almost 100% Faraday efficiency. This work provides a simple and universal strategy to prepare highly efficient bifunctional catalytic materials, promoting the development of Earth-abundant materials to catalyse seawater splitting to produce high-purity hydrogen.

Low oxygen tension favored expansion and hematopoietic reconstitution of CD34(+) CD38(-) cells expanded from human cord blood-derived CD34(+) Cells.

Oxygen tension is an important factor that regulates hematopoietic stem cells (HSCs) in both in vivo hematopoietic microenvironment and ex vivo culture system. Although the effect of oxygen tension on ex vivo expansion of HSCs was extensively studied, there were no clear descriptions on physiological function and gene expression analysis of HSCs under different oxygen tensions. In this study, the effects of oxygen tension on ex vivo expansion characteristics of human umbilical cord blood (UCB)-derived CD34(+) cells are evaluated. Moreover, the physiological function of expanded CD34(+) cells was assessed by secondary expansion ability ex vivo and hematopoietic reconstitution ability in vivo. Also, genetic profiling was applied to analyze the expression of genes related to cell function. It was found that low oxygen tension favored expansion of CD34(+) CD38(-) cells. Additionally, CD34(+) cells expanded under low oxygen tension showed better secondary expansion ability and reconstitution ability than those under atmospheric oxygen concentration. Finally, the genetic profiling of CD34(+) CD38(-) cells cultured under low oxygen tension was more akin to freshly isolated cells. These results collectively demonstrate that low oxygen tension was able to better maintain both self-renewal and hematopoietic reconstitution potential and may lay an experimental basis for clinical transplantation of HSCs.

Chinese biobanking initiatives.

Due to the requirement for comprehensive clinical research efforts in China, the importance of biobanking in modern clinical research is outlined in this overview. Hospitals, universities, and research institutes have been well organized as fundamental resources for Chinese biobanking initiatives and the resulting bio-sample collections. Here, a brief history and time line of development of biobanking in China will be introduced, as well as strategic designs for future biobanking development.

The Shanghai biobanking DNA quality control program.

Method validation is one of the crucial processes for a professional biobank. However, there are no routine guidelines specially designed for such studies. Therefore, in line with the need for competence in testing and calibration, the International Organization for Standardization (ISO) concept has been introduced to biobanking as a model for Quality Management Systems in this field. Accurate interpretation of the experimental data about the human genome depends on the quality of the genomic DNA. In this study, we focused on the validation of DNA quantitation by spectrophotometry, a basic bio-analytical method in molecular biology. The key factors of precision, accuracy testing, and linearity assessment are presented in assessing the method quality. Internal and external quality controls have been included as required. Our data show that the method of spectrophotometry is qualified for DNA quantitation.

The effects of ROS-mediating oxygen tension on human CD34(+)CD38(-) cells induced into mature dendritic cells.

Oxygen tension regulates the biological characteristics of hematopoietic stem and progenitor cells (HSPCs) by modulating intracellular reactive oxygen species (ROS). To better understand oxygen tension mechanism on HSPCs culture, gene expression analysis of human CD34(+)CD38(-) HSPCs was performed using microarrays. The CD34(+)CD38(-) HSPCs cultured under normoxia, hypoxia, or with N-acetyl cysteine (NAC, an ROS scavenger) were isolated for transcriptional profilings. Compared to normoxia group, 1 gene was up-regulated and 22 genes were down-regulated in hypoxia group, while 1 gene was up-regulated and 29 genes were down-regulated in NAC group. These differently expressed genes were involved in cell surface markers, blood activation and differentiation. The common down-regulated genes related to dendritic cells (DCs) maturation (CD80, CD86, and JAG1) were confirmed by real-time RT-PCR. Furthermore, the analysis of the phenotypes of DCs, including the DC-characteristic surface molecule CD1a, the costimulatory molecules CD80 and CD86, and HLA-DR, associated with the capacity of DCs to stimulate allogeneic T cells, showed that hypoxia-mediating ROS inhibited the potential of CD34(+)CD38(-) HSPCs differentiating to mature DCs. All these results demonstrated that hypoxia-reducing ROS down-regulated the genes driving CD34(+)CD38(-) HSPCs differentiation, which provides an interesting molecular hint to direct their development to DCs during cultures.

[Effect of regulating intracellular ROS with antioxidants on the ex vivo expansion of cord blood CD34+ cells].

AIM: To investigate the effect of regulating intracellular ROS with antioxidants on the ex vivo expansion of cord blood CD34(+) cells. METHODS: The levels of reactive oxygen species (ROS) in cord blood CD34(+) cells were reduced by superoxide dismutase (SOD), catalase (CAT) or N-acetylcysteine (NAC) in ex vivo expansion. The expansion of CD34(+) cells reducing ROS levels with antioxidant was studied. RESULTS: It was observed that the generation of ROS was increased markedly by the cytokine combination. ROS was eliminated by antioxidant effectively. With the addition of antioxidant at different concentration, ROS was reduced to different levels. The percentage of CD34(+) cells and CD34(+)CD38(-) cells, the colony growth of colony-forming cells (CFC) and the re-expansion capability of CD34(+) cells were enhanced by 2 000 U/mL SOD, 200 U/mL CAT or 2 mmol/L NAC. However, its effect on fold expansion of CD34(+) cells was not significant. The expansion of the cells was inhibited by 8 000 U/mL SOD, 1 000 U/mL CAT or 5 mmol/L NAC. CONCLUSION: The proportion of hematopoietic stem and progenitor cells in the culture substance was increased markedly with the addition of low dose antioxidants in ex vivo expansion.

Comparison between the effects of normoxia and hypoxia on antioxidant enzymes and glutathione redox state in ex vivo culture of CD34(+) cells.

Hypoxia maintained biological characteristics of CD34(+) cells through keeping lower intracellular reactive oxygen specials (ROS) levels. The effects of normoxia and hypoxia on antioxidant enzymes and glutathione redox state were compared in this study. Hypoxia decreased the mRNA expression of both catalase (CAT) and glutathione peroxidase (GPX), but not affected mRNAs expression of superoxide dismutase (SOD). While the cellular GPX activities under hypoxia were apparently less than those under normoxia, neither SOD activities nor CAT activities were affected by hypoxia. The analysis of glutathione redox status and ROS products showed the lower oxidized glutathione (GSSG) levels, the higher reduced glutathione (GSH) levels, the higher GSH/GSSG ratios, and the less O(2)- and H(2)O(2) generation under hypoxia (versus normoxia). Meanwhile more primary CD34(+)CD38(-) cells were obtained when cultivation was performed under hypoxia or with N-acetyl cysteine (the precursor of GSH) under normoxia. These results demonstrated the different responses of anti-oxidative mechanism between normoxia and hypoxia. Additionally, the present study suggested that the GSH-GPX antioxidant system played an important role in HSPCs preservation by reducing peroxidation.

Role of the plasma membrane ROS-generating NADPH oxidase in CD34+ progenitor cells preservation by hypoxia.

Hypoxia favored the preservation of progenitor characteristics of hematopoietic stem and progenitor cells (HSPCs) in bone marrow. This work aimed at studying the role of reactive oxygen species (ROS)-generating NADPH oxidase system regulated by hypoxia in ex vivo cultures of cord blood CD34+ cells. The results showed that NADPH oxidase activity and ROS generation were reduced in hypoxia with respect to normal oxygen tension. Meanwhile the ROS generation was found to be inhibited by diphenyleneiodonium (the NADPH oxidase inhibitor), or N-acetylcysteine (the ROS scavenger). Accordingly NADPH oxidase mRNA and p67 protein levels decreased in hypoxia. The analysis of progenitor characteristics, including the proportion of cultured cells expressing the HSPCs marker CD34+CD38-, colony production ability of the colony-forming cells (CFCs), and the re-expansion capability of the cultured CD34+ cells, showed that either 5% pO(2) or reduced ROS favored preserving the characteristics of CD34+ progenitors, and promoted the expansion of CD34+CD38- cells as well. The above results demonstrated that hypoxia effectively maintained biological characteristics of CD34+ cells through keeping lower intracellular ROS levels by regulating NADPH oxidase.