Dry Reforming of Methane over Pyrochlore-Type La2Ce2O7-Supported Ni Catalyst: Effect of Particle Size of Support.

The properties of supports (such as oxygen vacancies, oxygen species properties, etc.) significantly impact the anti-carbon ability due to their promotional effect on the activation of CO2 in dry reforming of methane (DRM). Herein, pyrochlore-type La2Ce2O7 compounds prepared using co-precipitation (CP), glycine nitrate combustion (GNC) and sol-gel (S-G) methods, which have highly thermal stability and unique oxygen mobility, are applied as supports to prepare Ni-based catalysts for DRM. The effect of the calcining temperature (500, 600 and 700 °C) on La2Ce2O7(CP) has also been investigated. Based on multi-technique characterizations, it is found that the synthesis method and calcination temperature can influence the particle size of the La2Ce2O7 support. Changes in particle size strongly modulate the pore volume, specific surface area and numbers of surface oxygen vacancies of the La2Ce2O7 support. As a result, the distribution of supported Ni components is affected due to the different metal-support interaction, thereby altering the activity of the catalysts for cracking CH4. Moreover, the supports' abilities to adsorb and activate CO2 are also adjusted accordingly, accelerating the removal of the carbon deposited on the catalysts. Finally, La2Ce2O7(CP 600) with an appropriate particle size exhibits the best catalytic activity and stability in DRM.

Comparative analysis on the outcomes in circumcising children using modified Chinese ShangRing and conventional surgical circumcision.

OBJECTIVE: To compare the differences and outcomes of surgical procedures, clinical effect, complications and patients' satisfaction between disposable oval-shaped circumcision device (Modified Chinese ShangRing series, Kiddie love®) and conventional circumcision in the treatment of children with phimosis or redundant prepuce. METHODS: The clinical data were retrospectively analyzed in 114 children with phimosis or redundant foreskin undergone circumcision using a disposable oval-shaped circumcision device, a modified Chinese ShangRing series, Kiddie Love® (Kiddie Love group) in our hospital between January 2018 and February 2020, and another 114 children with similar conditions circumcised by conventional surgical procedure before January 2018 (conventional group). The two groups were compared regarding the operative time, intraoperative blood loss, postoperative pain scores, healing time, the incidence of complications and guardian's satisfaction. RESULTS: Circumcision was successfully completed in children in both groups. The operative time, intraoperative blood loss, postoperative pain scoring in 24 h by VAS, pain at the removal of the device or stitches and wound healing were (6.4 ± 1.6) min, (34.1 ± 6.4) min; (0.7 ± 0.2) ml, (2.6 ± 0.6) ml; (2.2 ± 1.0) points, (1.3 ± 0.5) points; (23.7 ± 3.9)day, (15.9 ± 2.8)day, respectively for Kiddie Love group and conventional group(either P < 0.05 or P > 0.05). The two groups were significantly different in the incidence of hematoma, edema and incision dehiscenceyet were insignificant in incision infection. Children in both groups were followed up from 6 to 31 months (mean: 23 months), and the satisfaction rate was 94.7% (108/114) in parents of the children circumcised by the ShangRing and 83.3% (95/114) in those of children treated by conventional circumcision (P < 0.05). CONCLUSION: Modified Chinese ShangRing, Kiddie Love®, has superiorities, including simpler procedure, shorter operative time, less blood loss, fewer complications, better cosmetic results and higher satisfaction of patients over conventional circumcision in the treatment of children with phimosis or redundant foreskin, and worthy of wider clinical recommendation.

Transcriptome Differences in Porcine Alveolar Macrophages from Tongcheng and Large White Pigs in Response to Highly Pathogenic Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Infection.

Porcine reproductive and respiratory syndrome virus (PRRSV) is a single-stranded positive-sense RNA virus that can cause devastating reproductive failure and respiratory tract lesions, which has led to serious damage to the swine industry worldwide. Our previous studies have indicated that Tongcheng (TC) pigs, a Chinese local breed, have stronger resistance or tolerance to PRRSV infection than Large White (LW) pigs. This study aims to investigate their host transcriptome differences in porcine alveolar macrophages (PAMs) at 7 days post challenge. Transcriptome profiling of PAMs from PRRSV infected and control pigs of these two breeds were performed using RNA-sequencing. For both breeds, there were 1257 common differentially expressed genes (DEGs) in response to PRRSV infection, involving hepatic fibrosis/hepatic stellate cell activation, phospholipase C, and granulocyte adhesion and diapedesis pathways. For TC pig, 549 specific DEGs were identified, including VAV2, BCL2 and BAX, which were enriched in activation of leukocyte extravasation and suppression of apoptosis. While, 898 specific DEGs were identified in LW pigs, including GNAQ, GNB5, GNG2, CALM4 and RHOQ, which were involved in suppression of Gαq and PI3K-AKT signaling. This study provides an insight into the transcriptomic comparison of resistant and susceptible pigs to PRRSV infection. TC pigs may promote the extravasation and migration of leukocytes to defend against PRRSV infections and suppress apoptosis of the infected macrophages to increase antigen presentation, thereby reducing the lung lesions.

Development of a colloidal gold immunochromatographic strip assay for simple and fast detection of human α-lactalbumin in genetically modified cow milk.

The qualitative and quantitative declaration of food ingredients is important to consumers, especially for genetically modified food as it experiences a rapid increase in sales. In this study, we designed an accurate and rapid detection system using colloidal gold immunochromatographic strip assay (GICA) methods to detect genetically modified cow milk. First, we prepared 2 monoclonal antibodies for human α-lactalbumin (α-LA) and measured their antibody titers; the one with the higher titer was used for further experiments. Then, we found the optimal pH value and protein amount of GICA for detection of pure milk samples. The developed strips successfully detected genetically modified cow milk and non-modified cow milk. To determine the sensitivity of GICA, a quantitative ELISA system was used to determine the exact amount of α-LA, and then genetically modified milk was diluted at different rates to test the sensitivity of GICA; the sensitivity was 10 µg/mL. Our results demonstrated that the applied method was effective to detect human α-LA in cow milk.

Investigation of four candidate genes (IGF2, JHDM1A, COPB1 and TEF1) for growth rate and backfat thickness traits on SSC2q in Large White pigs.

As important quantitative traits, the growth rate and backfat thickness are controlled by multiple genes. The aim of this investigation was to evaluate the effect of the single and multiple SNPs of four candidate genes (IGF2, JHDM1A, COPB1 and TEF-1) on growth rate and backfat thickness. The four candidate genes were mapped on the p arm of SSC 2, and there are several QTLs, such as average daily gain, backfat thickness, an imprinted QTLs affecting muscle mass and fat deposition have been reported in this region. The polymorphisms of these genes were detected using PCR-RFLP methods, mixed procedure was used to analyze the single marker association with the growth and backfat thickness traits, and the gene-gene combination was investigated using multiple-markers analysis. The single marker association analysis indicated that the IGF2 intron-3 g.3072G > A and the substitution g.93G > A of TEF-1 gene were significantly associated with the age at 100 kg (P < 0.05). The JHDM1A 3'UTR g.224C > G, the c.3096C > T polymorphism of COPB1 gene and the substitution g.93G > A of TEF-1 gene were all significantly associated with the backfat at the shoulder (P < 0.05), backfat at the last rib, backfat at the lumbar, and the average backfat thickness, respectively. The multiple-markers analysis indicated that IGF2 and TEF-1 integrated gene networks for the age at 100 kg. Therefore, we can suggest that the polymorphism of IGF2 and TEF-1 gene could be used in marker-assisted selection for the age at 100 kg in Large White pigs.

Detection of HbsAg and hATIII genetically modified goats (Caprahircus) by loop-mediated isothermal amplification.

In this study, sensitive and rapid detection systems were designed using a loop-mediated isothermal amplification (LAMP) method to detect the genetically modified goats. A set of 4 primers were designed for each exogenous nucleic acids HBsAg and hATIII. The DNA samples were first amplified with the outer and inner primers and released a single-stranded DNA,of which both ends were stem-loop structure. Then one inner primer hybridized with the loop, and initiated displacement synthesis in less than 1 h. The result could be visualized by both agarose gel electrophoresis and unaided eyes directly after adding SYBR GREEN 1. The detection limit of LAMP was ten copies of target molecules, indicating that LAMP was tenfold more sensitive than the classical PCR. Furthermore, all the samples of genetically modified goats were tested positively by LAMP, and the results demonstrated that the LAMP was a rapid and sensitive method for detecting the genetically modified organism.

Molecular characterization, expression profiles of the porcine SDC2 and HSPG2 genes and their association with hematologic parameters.

Heparan sulfate proteoglycans (HSPGs) located at the cell surface and in the extracellular matrix of most animal tissues are proteoglycan coreceptors that carry heparan sulfate chains, and play a vital role in infections of many diseases. HSPGs are classified as glypican, syndecan, perlecan and agrin according to different core proteins. Syndecan-2 (SDC2) is one of the four coding genes of syndecan, while heparan sulfate proteoglycan 2 (HSPG2) is for perlecan. In this study, we cloned the cDNA of porcine SDC2 and analyzed its genomic structure. The porcine SDC2 and HSPG2 were mapped to SSC4p12-13 and SSC6q24-25 by the SCHP panel respectively, further IMpRH panel analysis showed that they were most closely linked to the marker SWR362 and SW709. One special domain named the 4.1 m domain (putative band 4.1 homologues' binding motif) was found in the prediction amino acid sequence of porcine SDC2. RT-PCR showed that both of porcine SDC2 and HSPG2 were expressed widely in detected tissues: heart, liver, spleen, lung, kidney, stomach, muscle, fat and lymph. Upon stimulation in healthy Tongcheng piglets with PRRSV, SDC2 mRNA did not induce a prominent change in the PAMs, while HSPG2 mRNA displayed a dramatic decline. In addition, synonymous mutation g.32A>G of the SDC2 gene was detected and confirmed to be significantly associated with hematocrit, mean corpuscular volume and hemoglobin concentration in the peripheral blood (p < 0.05). A single nucleotide polymorphism g.83.A>G was found in the HSPG2 gene and the association analysis showed that it was significantly associated with mean corpuscular hemoglobin (p < 0.05). Our results confirmed the relation of porcine SDC2 and HSPG2 to the immunity in pigs, and these two genes could be used as candidate genes for improving immune traits in industrial pig breeding.

Immunochromatography detection of human lactoferrin protein in milk from transgenic cattle.

Transgenic technologies have opened a new era of transgenesis, characterized by manipulating intraspecies or interspecies genes in microorganisms, plants, or animals to change them in desired directions. The advent of genetically modified animals and related products has raised the need for analytical methods, nucleotide- or protein-based, to qualitatively and quantitatively determine the biotechnology ingredients. In this study, we collected milk samples containing human lactoferrin (hLF) protein, to exploit appropriate detection means for exogenous hLF protein. We preliminarily developed two types of competitive immunochromatography strips for quick detection, based on gold-conjugated hLF protein or gold-conjugated polyclonal antibody. As control methods, sodium dodecyl sulfate polyacrylamide gel electrophoresis, dot blot, and Western blot methods were used to check the accuracy of strips, and highly sensitive ELISA with chemiluminescent substrates was developed to determine the concentration of hLF in milk. Comparing the test results of lateral flow strips with qualitative assays, we found our strips gave the same results in a few minutes, showing great advantages with no need of professional technicians or any equipment. Our results demonstrated that all the applied methods were effective to detect hLF, suggesting that they could be used to monitor the production of transgenic milk.

Repair of missing linker defects in UiO-66 by a "molecular patch" boosting the 1-hexene hydroformylation reaction.

Fabrication of MOFs with missing linker defects has become a common means to improve catalytic performances. However, the stability of the defects deserves to be investigated first. In this work, we found that 3-phenylpropionaldehyde (3-PPA) could coordinate with the missing linker defects of UiO-66, which highlighted the instability of the missing linker defects. 3-PPA acted as a molecular patch for the modification of the Rh/UiO-66 catalyst, which repaired the open Zr6 sites and resulted in a remarkable improvement of aldehyde selectivity (from 50.0% to 89.6%) in 1-hexene hydroformylation.

Introduction of TiO2 enhancing the catalytic performance of Ti(SO4)2/SiO2 for dimethyl ether oxidation.

The introduction of a small amount of TiO2 changes the surface properties of the SiO2 material, which further significantly affects the dispersion state of Ti(SO4)2. The differences in acidity and redox caused by the distribution of Ti(SO4)2 are closely related to the catalyst performance for dimethyl ether (DME) oxidation. In particular, the calcination temperature could adjust the surface hydroxyl content of TiO2/SiO2, which determines the dispersion of Ti(SO4)2 components, resulting in distinct acid sites and Ti valence. The most number of weak acid sites and the highest proportion of Ti3+/Ti4+ in the Ti(SO4)2/TS-400 °C catalyst remarkably promote the formation of dimethoxymethane (DMM) from 14.4% to 82.6%, compared to the Ti(SO4)2/SiO2 catalyst.

Highly efficient acrylic acid production from formaldehyde and acetic acid over the NASICON-type catalyst.

The condensation of formaldehyde and acetic acid to acrylic acid (AA) is considered as one of the important routes for the clean and high value utilization of coal-based methanol derivatives. Herein, we successfully synthesized environment-friendly NASICON catalysts using Ti(SO4)2 as the titanium source. With guaranteed high selectivity (∼78%), the space time yield of AA + MA (methyl acrylate) can be up to 123.9 µmol g-1 min-1, far higher than the results reported previously. Based on the characterizations, it is demonstrated that the modulation of the acidic and basic properties (including distribution, ratio of B/L, etc.) led by the specific elemental and hybrid TiP2O7 phase plays crucial roles in catalyst supremacy.

Unsaturated Penta-Coordinated Mo5c5+ Sites Enabled Low-Temperature Oxidation of C-H Bonds in Ethers.

Selective oxidation of C-H bonds under mild conditions is one of the most important and challenging issues in utilization of energy-related molecules. Molybdenum oxide nanostructures containing Mo5+ species are effective for these reactions, but the accurate identification of the structure of active Mo5+ species and the catalytic mechanism remain unclear. Herein, unsaturated penta-coordinated Mo5c5+ with a high fraction in MoOx fabricated by the hydrothermal method were identified as the active sites for low-temperature oxidation of dimethyl ether (DME) by the deep correlation of characterizations, density functional theory calculations, and activity results, giving a methyl formate selectivity of 96.3% and DME conversion of 12.5% at unreported 110 °C. Low-temperature electron spin resonance (ESR) and quasi in situ X-ray photoelectron spectra (XPS) with the designed experiments confirm that the Mo5c5+ species can be formed in situ. Molybdenum located at the pentachronic site is preferable to significantly promote the oxidation of the C-H bond in CH3O* at lower temperatures.

Detection of two exogenous genes in transgenic cattle by loop-mediated isothermal amplification.

Nucleotide-based analytical approaches are indispensable and effective, targeting for the transgenic ingredients in biotechnical products in terms of safety assessment. In this study, a loop-mediated isothermal amplification method was developed for the specific detection of exogenous nucleic acids of hLTF/hLALBA-induced transgenic cattle. The detection limit of the LAMP method was proved to be as low as 10 copies of target molecules in optimized systems, and to be 10-100 times more sensitive than the conventional PCR. Furthermore, fluorescent dye SYBR Green I was used to visualize the color changes of LAMP products by naked eyes in daylight, which resulted in distinct colors between positive and negative reactions. For the detection of transgenes, all the transgenic samples collected from hLTF and hLALBA-induced cattle were amplified by LAMP in 1 h, followed by direct visual SYBR Green I dying or gel electrophoresis. Results showed that transgenic and non-transgenic samples exhibited distinct properties in colors or electrophoresis profiles. Thus, all the results indicated that the LAMP assay was a simple and convenient method for the test of transgenic animals.

Association of two porcine reproductive and respiratory syndrome virus (PRRSV) receptor genes, CD163 and SN with immune traits.

CD163 and sialoadhesin (SN) were reported as two essential receptors for the porcine reproductive and respiratory syndrome virus. To investigate the relationship between these two genes and porcine immunity, we assigned porcine CD163 and SN respectively to SSC5q21-q24 and SSC17q23 by IMpRH. Expression profiles revealed that CD163 and SN were ubiquitously expressed in ten tissues, and were expressed highly in lymph gland, spleen and liver, which implied the potential functions of CD163 and SN in immunity. Moreover, a single nucleotide polymorphism (SNP) c.3534C>T was found in 3'-UTR of the CD163 gene and association analysis showed that this gene was significantly associated with the IgG content in blood (P < 0.05). A novel missense mutation c.878A>G located in exon4 of the SN gene which caused the amino acid transition from histidine to arginine was detected, and it was significantly associated with the WBC count in the peripheral blood (P < 0.05). These results provided fundamental evidence for CD163 and SN as two functional candidate genes affecting immunity in pigs.

Investigation of four porcine candidate genes (H-FABP, MYOD1, UCP3 and MASTR) for meat quality traits in Large White pigs.

Meat quality traits are economically important traits of swine, and are controlled by multiple genes as complex quantitative traits. In the present study four genes, H-FABP (heart fatty acid-binding protein), MASTR (MEF2 activating motif and SAP domain containing transcriptional regulator), UCP3 (uncoupling protein 3) and MYOD1 (myogenic differentiation 1) were researched in Large White pigs. The polymorphisms H-FABP T/C of 5'UTR, MYOD1 g.257 A>C, UCP3 g.1406 G>A in exon 3 and MASTR c.187 C>T have been reported to be associated with meat quality traits in pigs. The aim of this study was to analyze the effect of single and multiple markers for single traits in Large White pigs. The single marker association analysis showed that the H-FABP and MASTR genes were associated with IMF (intramuscular fat content) (P < 0.05), and that the g.257 A>C of MYOD1 gene was most significantly related to muscle pH value (P < 0.01). The multiple markers for IMF were analyzed by combining the markers and quantitative trait modes into the linear regression. The results revealed that H-FABP and MASTR integrate gene networks for IMF. Thus, our study results suggested that H-FABP and MASTR polymorphisms could be used as genetic markers in the marker-assisted selection towards the improvement of IMF in Large White pigs.

Complete chloroplast genome of Plantago asiatica and its phylogenetic position in Plantaginaceae.

Plantago asiatica, an herbaceous perennial species of Plantaginaceae, has been used as a traditional herbal medicine plant in China. In this study, the complete chloroplast (cp) genome of P. asiatica was sequenced and assembled using genome skimming data. The cp genome was 165,045 bp in length including the large single-copy (LSC, 82,964 bp) and small single-copy (SSC, 4,633 bp) regions separated by two copies of inverted region (IR, 38,724 bp). The cp genome encoded 113 unique genes, consisting of 79 protein-coding genes, 30 tRNA genes, and four rRNA genes, additionally with 27 duplicated genes in the IR regions. Phylogenetic analysis indicated that the representative species from Plantago was monophyletic and they were divided into four subgenera. P. asiatica belongs to the subgenus Plantago and was sister to P. rigida with high bootstrap value support.

Integration of Transcriptome and Proteome in Lymph Nodes Reveal the Different Immune Responses to PRRSV Between PRRSV-Resistant Tongcheng Pigs and PRRSV-Susceptible Large White Pigs.

Porcine reproductive and respiratory syndrome (PRRS) is an infectious disease that seriously affects the swine industry worldwide. Understanding the interaction between the host immune response and PRRS virus (PRRSV) can provide insight into the PRRSV pathogenesis, as well as potential clues to control PRRSV infection. Here, we examined the transcriptome and proteome differences of lymph nodes between PRRSV-resistant Tongcheng (TC) pigs and PRRSV-susceptible Large White (LW) pigs in response to PRRSV infection. 2245 and 1839 differentially expressed genes (DEGs) were detected in TC and LW pigs upon PRRSV infection, respectively. Transcriptome analysis revealed genetic differences in antigen presentation and metabolism between TC pigs and LW pigs, which may lead to different immune responses to PRRSV infection. Furthermore, 678 and 1000 differentially expressed proteins (DEPs) were identified in TC and LW pigs, and DEPs were mainly enriched in the metabolism pathways. Integrated analysis of transcriptome and proteome datasets revealed antigen recognition capacity, immune activation, cell cycles, and cell metabolism are important for PRRSV clearance. In conclusion, this study provides important resources on transcriptomic and proteomic levels in lymph nodes for further revealing the interaction between the host immune response and PRRSV, which would give us new insight into molecular mechanisms related to genetic complexity against PRRSV.

Selective oxidation conversion of methanol/dimethyl ether.

As important platform compounds, methanol and dimethyl ether (DME) are vital bridges between the coal chemical, petrochemical and fine chemical industries. At present, the synthesis of methanol/DME has been industrialized, and the production capacity is much larger than the market demand. Therefore, the conversion of methanol/DME into more valuable chemicals is an important and significant topic. The synthesis of high value-added oxygenated chemicals and diesel oil additives from methanol/DME by an oxidation method has attracted substantial attention due to it being green and environmentally friendly and having good atom economy. In this feature article, we have summarized the recent advances in the synthesis of formaldehyde, methyl formate, dimethoxymethane, and polyoxymethylene dimethyl ethers, from the selective oxidation of methanol/DME, and further discussed the adsorption and activation of reactant molecules, selective cleavage of C-O, C-H or O-H bonds in methanol/DME molecules and the C-O chain growth in the target products. In the end, major challenges and future prospects are proposed from the viewpoint of catalyst design and application. It is expected that this feature article will provide theoretical guidance for the activation and cleavage of C-O, C-H, or O-H bonds in other small molecules of alcohol/ether as well as low-carbon alkanes, so as to synthesize high value-added chemicals.

Change of Gut Microbiota in PRRSV-Resistant Pigs and PRRSV-Susceptible Pigs from Tongcheng Pigs and Large White Pigs Crossed Population upon PRRSV Infection.

Porcine Reproductive and Respiratory Syndrome (PRRS) is one of the serious infectious diseases that threatens the swine industry. Increasing evidence shows that gut microbiota plays an important role in regulating host immune responses to PRRS virus (PRRSV). The aim of this study was to investigate gut microbiota difference between PRRSV-resistant pigs and PRRSV-suspectable pigs derived from a Tongcheng pigs and Large White pigs crossed population. PRRSV infection induces an increase in the abundance and diversity of gut microbiota. Correlation analysis showed that 36 genera were correlated with viral loads or weight gain after PRRSV infection. Prevotellaceae-NK3B31-group, Christensenellaceae-R7-group, and Parabacteroides were highly correlated with both viral load and weight gain. Notably, the diversity and abundance of beneficial bacteria such as Prevotellaceae-NK3B31-group was high in resistant pigs, and the diversity and abundance of pathogenic bacteria such as Campylobacter and Desulfovibrio were high in susceptible pigs. Gut microbiota were significantly associated with immune function and growth performance, suggesting that these genera might be related to viremia, clinical symptoms, and disease resistance. Altogether, this study revealed the correlation of gut microbiota with PRRSV infection and gut microbiota interventions may provide an effective prevention against PRRSV infection.

Oxidative coupling of methane over Mo-Sn catalysts.

A novel Mo-Sn catalyst for the oxidative coupling of methane was designed using a hydrothermal method. At 650 °C, the conversion of methane was 8.6% and the selectivity of the C2 hydrocarbons reached as high as 98.1% over the Mo1Sn3 catalyst, with a CO2 selectivity of only 0.8%. We demonstrated that the deep oxidation of methane to CO2 was further inhibited due to the synergistic effects of moderately strong basic sites and reactive oxygen species on the catalyst surface.