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Rural waste accumulation leads to heavy metal soil pollution, impacting microbial communities. However, knowledge gaps exist regarding the distribution and occurrence patterns of bacterial communities in multi-metal contaminated soil profiles. In this study, high-throughput 16 S rRNA gene sequencing technology was used to explore the response of soil bacterial communities to various heavy metal pollution in rural simple waste dumps in karst areas of Southwest China. The study selected three habitats in the center, edge, and uncontaminated areas of the waste dump to evaluate the main factors driving the change in bacterial community composition. Pollution indices reveal severe contamination across all elements, except for moderately polluted lead (Pb); contamination severity ranks as follows: Mn > Cd > Zn > Cr > Sb > V > Cu > As > Pb. Proteobacteria, Actinobacteria, Chloroflexi, and Acidobacteriota predominate, collectively constituting over 60% of the relative abundance. Analysis of Chao and Shannon indices demonstrated that the waste dump center boasted the greatest bacterial richness and diversity. Correlation data indicated a predominant synergistic interaction among the landfill's bacterial community, with a higher number of positive associations (76.4%) compared to negative ones (26.3%). Network complexity was minimal at the dump's edge. RDA analysis showed that Pb(explained:46%) and Mn(explained:21%) were the key factors causing the difference in bacterial community composition in the edge area of the waste dump, and AK(explained:42.1%) and Cd(explained:35.2%) were the key factors in the center of the waste dump. This study provides important information for understanding the distribution patterns, co-occurrence networks, and environmental response mechanisms of bacterial communities in landfill soils under heavy metal stress, which helps guide the formulation of rural waste treatment and soil remediation strategies.

Artemisia argyi, a perennial herb of the genus Artemisia in the family Asteraceae, holds significant importance in Chinese traditional medicine, referred to as “Aicao”. Here, we report a high-quality reference genome of Artemisia argyi L. cv. beiai, with a genome size up to 4.15 Gb and a contig N50 of 508.96 Kb, produced with third-generation Nanopore sequencing technology. We predicted 147,248 protein-coding genes, with approximately 68.86% of the assembled sequences comprising repetitive elements, primarily long terminal repeat retrotransposons(LTRs). Comparative genomics analysis shows that A. argyi has the highest number of specific gene families with 5121, and much more families with four or more members than the other 6 plant species, which is consistent with its more expanded gene families and fewer contracted gene families. Furthermore, through transcriptome sequencing of A. argyi in response to exogenous MeJA treatment, we have elucidated acquired regulatory insights into MeJA’s impact on the phenylpropanoid, flavonoid, and terpenoid biosynthesis pathways of A. argyi. The whole-genome information obtained in this study serves as a valuable resource for delving deeper into the cultivation and molecular breeding of A. argyi. Moreover, it holds promise for enhancing genome assemblies across other members of the Asteraceae family. The identification of key genes establishes a solid groundwork for developing new varieties of Artemisia with elevated concentrations of active compounds.

Abstract Stereoselectivity control and understanding in the metal-catalyzed reactions are fundamental issues in catalysis. Here we report sterically controlled rhodium-catalyzed SN2’-type substitution reactions of optically active tertiary propargylic alcohols with arylmetallic species affording the non-readily available enantioenriched tetrasubstituted allenes via either exclusive syn- or anti-β-OH elimination, respectively, under two sets of different reaction parameters. Detailed mechanistic experiments and density functional theory (DFT) studies reveal that the exclusive anti-Rh(I)-OH elimination is dictated by the simultaneous aid of in situ generated boric acid and ambient water, which act as the shuttle in the hydroxy relay to facilitate the Rh(I)-OH elimination process via a unique ten-membered cyclic transition state (anti-TS2_u). By contrast, the syn-Rh(III)-OH elimination in C–H bond activation-based allenylation reaction is controlled by a four-membered cyclic transition state (syn- TS3) due to the steric surroundings around the Rh(III) center preventing the approach of the other assisting molecules. Under the guidance of these mechanistic understandings, a stereodivergent protocol to construct the enantiomer of optically active tetrasubstituted allenes from the same starting materials is successfully developed.

Temperature-triaxial pressure permeability testing at the axial pressure of 8 MPa and confining pressure of 10 MPa, closed shale system pyrolysis experiment by electrical heating and scanning electron microscopy analysis are used to study the evolution mechanism of in-situ permeability in the direction parallel to bedding of low-maturity shale from Member 2 (K2n2) of Cretaceous Nenjiang Formation in northern Songliao Basin with mainly Type I kerogen under the effect of temperature. With the increasing temperature, the in-situ permeability presents a peak-valley-peak tendency. The lowest value of in-situ permeability occurs at 375 °C. Under the same temperature, the in-situ permeability decreases with the increase of pore pressure. The in-situ permeability evolution of low-maturity shale can be divided into 5 stages: (1) From 25 °C to 300 °C, thermal cracking and dehydration of clay minerals improve the permeability. However, the value of permeability is less than 0.01×10−3 μm2; (2) From 300 °C to 350 °C, organic matter pyrolysis and hydrocarbon expulsion result in mineral intergranular pores and micron pore-fractures, these pores and fractures form an interconnected pore network at limited scale, improving the permeability. But the liquid hydrocarbon, with high content of viscous asphaltene, is more difficult to move under stress and more likely to retain in pores, causing slow rise of the permeability. (3) From 350 °C to 375 °C, pores are formed by organic matter pyrolysis, but the adsorption swelling of liquid hydrocarbon and additional expansion thermal stress constrained by surrounding stress compress the pore-fracture space, making liquid hydrocarbon difficult to expel and permeability reduce rapidly. (4) From 375 °C to 450°C, the interconnected pore network between different mineral particles after organic matter conversion, enlarged pores and transformation of clay minerals promote the permeability to increase constantly even under stress constraints. (5) From 450°C to 500 °C, the stable pore system and crossed fracture system in different bedding directions significantly enhance the permeability. The organic matter pyrolysis, pore-fracture structure and surrounding stress in the different stages are the key factors affecting the evolution of in-situ permeability.

Transition-metal-catalyzed couplings of propargylic alcohol derivatives with organometallic reagents proceeds via two-electron transformations, which present limitations in scope and selectivity. Here, the authors present visible-light-mediated copper-catalyzed cyanation of propargylic oxalates to form allenenitriles via a one-electron pathway

To understand the distribution characteristics and potential ecological risks of heavy metals in soils in the typical volcanic area, 2,592 soil samples were collected from the surface layer (0–20 cm) and 269 samples were collected from the middle (80–100 cm) and deep layers (180–200 cm) in northeast of Hainan province, China. Accordingly, eight heavy metals (Cu, Pb, Zn, Cr, Ni, Cd, As, and Hg) were analyzed and determined. The effects of different parent materials and land use types on the accumulation of heavy metals in soils were compared, and the primary heavy metal sources were analyzed. The pollution level and ecological risk of heavy metals in soils in the study area were evaluated using the geo-accumulation index (Igeo) and potential ecological risk indices (Ei & RI). The results showed that, except that of Pb, the median concentrations of the analyzed heavy metals in the surface soils were higher than the background concentrations in the Hainan Island soils, indicating varying degrees of accumulation. The influence of land use type on the accumulation of heavy metals in surface soils varied from that of the parent materials. Anthropogenic activities highly influenced As, Cd, Hg, and Pb concentrations, whereas geological conditions primarily influenced Cr, Cu, Ni, and Zn concentrations. The Igeo results showed that the mean value of the eight metal elements were greater than zero, except for Pb. In the surface soils, the Igeo values of As, Cd, Hg, and Zn mostly fell into the light to moderate pollution class, and those of Cr, Cu, and Ni fell into the medium and heavy pollution class. The RI of the study area showed a high to significantly high ecological risk because of the Cd, Hg, and Ni concentrations. The results give a new insight in the parent material's geochemical control on the heavy metal elements in soils, and it can serve as a reference for the background value of local soil heavy metals and provide a scientific basis for controlling the potential ecological risk of heavy metals and reasonable land use plans.

Endoplasmic reticulum stress (ERS)-mediated autophagy is indispensable for modulation of replication and pathogenesis of numerous mammalian viruses. We have previously shown that classical swine fever virus (CSFV) infection induces ERS-mediated autophagy for maintaining viral replication both in vivo and in vitro, however, the underlying mechanism remains unclarified. Here we found that CSFV infection activates the PERK pathway-dependent complete autophagy to promote viral replication in cultured PK-15 and 3D4/2 cells. Likewise, our results also suggested the essential roles of the IRE1/GRP78-mediated complete autophagy in CSFV replication in vitro. Furthermore, we suggested that CSFV infection induces activation of the PERK and IRE1 pathway for potential immunoregulation via promoting transcription of proinflammatory cytokine (IFN-γ and TNF-α) genes in the CSFV-infected cells. Finally, pharmacological treatment of PERK- or IRE1-pathway regulators, and the corresponding SiRNAs interventions did not affect the viabilities of the cells, excluding the potential interference elicited by altered cell viabilities. Taken together, our results suggest that CSFV infection induces complete autophagy through activation of the PERK and IRE1 pathway to facilitate viral replication in cultured cells, and modulation of proinflammatory cytokines may be a potential mechanism involved in this event. Our findings will open new horizons for molecular mechanisms of sustainable replication and pathogenesis of CSFV, and lay a theoretical foundation for the development of ERS-autophagy-targeting therapeutic strategies for clinical control of CSF.

Hainan Island is the main planting base of tropical plants in China.Evaluating the level of soil pollution in this area has a great significance.In this study, we assessed the contamination levels, sources and ecological risk of 16 priority polycyclic aromatic hydrocarbons (PAHs) in agricultural soils of northern Hainan Island.A total of 100 surface soil samples were collected from plantations (coffee, banana, yam, sugarcane, orange, passion fruit and guava) and analyzed for PAHs concentration using gas chromatography equipped with a mass spectrometry detector (GC-MS).The average of ∑16PAHs from plantation soil was 37.6 ng/g, which was below the background of national soil and the no pollution limit of 200 ng/g determined by Netherlands.Three-, four- and five-ring PAHs were dominant components, accounting for 25.8%, 26.8% and 23.5% of the total PAHs, respectively.Source analysis suggested that PAHs of soil in these plantations were mainly derived from the exhaust gas of locomotives and partially from oil spill as well as low temperature combustion of coal and biomass.In ecological risk assessment, the benzo(a) pyrene equivalent concentration (∑16BaPeq) presented a much lower level than the guideline values announced by Chinese Environmental Protection Agency, demonstrating that the PAHs contamination level in solis was acceptable.

Qiongzhong Limushan-Wanling area is located in the middle of Hainan Island, where has an abundance of selenium-rich and iodine-rich soil resources.The distribution characteristics of Se and I contents were analyzed based on the analysis results of soil samples in the topsoil (0-20 cm), middle-layer-soil(80-100 cm), and deep-soil (180-200 cm) of the study area.The correlation characteristics of Se and I in soil and their relationship with elevation potentially indicate that the input of rainfall to soil Se and I is a key factor leading to the enrichment of Se and I.By analyzing the correlation and change law between the contents of Se, I and the contents of pH, soil organic matter, Al2O3 and Fe2O3 in top, middle and deep layer soil, the enrichment and migration of Se and I in the vertical section of soil in the study area was summarized.These results can provide scientific basis for the efficient use of local high-quality land resources and provide new evidence for the study of soil Se source and migration.

Newcastle disease (ND) is an acute and highly contagious disease caused by the Newcastle disease virus (NDV) infecting poultry, which has caused great harm to the poultry industry around the world. Rapid diagnosis of NDV is important to early treatment and early institution of control measures. In this review, we comprehensively summarize the most recent research into NDV, including historical overview, molecular structure, and infection mechanism. We then focus on detection strategies for NDV, including virus isolation, serological assays (such as hemagglutination and hemagglutination-inhibition tests, enzyme linked immunosorbent assay, reporter virus neutralization test, Immunofluorescence assay, and Immune colloidal gold technique), molecular assays (such as reverse transcription polymerase chain reaction, real-time quantitative PCR, and loop-mediated isothermal amplification) and other assays. The performance of the different serological and molecular biology assays currently available was also analyzed. To conclude, we examine the limitations of currently available strategies for the detection of NDV to lay the groundwork for new detection assays.

Chiral pyrazolone derivatives show promising biological activity in commercial drugs. Here, the authors report an enantioselective allenylation of pyrazolones by fine tuning of Trost’s ligands, which leads to a chiral pocket featuring high efficiency and asymmetric induction in the catalytic process.

Chiral amines find use as chiral ligands, resolving reagents and versatile building blocks as well as in pharmaceuticals and agrochemicals. Here, the authors developed Pyrinap ligands for the copper-catalyzed enantioselective A3-coupling of terminal alkynes, aldehydes, and amines affording optically active propargylic amines.

Abstract Background Capsid (C) protein plays an important role in the replication of classical swine fever virus (CSFV). The ubiquitin proteasome system (UPS) involves in replication of many viruses via modulation of viral proteins. The relationship of CSFV with UPS is poorly understood and the impact of 26S proteasome on C protein has never been reported before. Methods In this study, fused C protein with an EGFP tag is expressed in PK-15 and 3D4/2 cells. MG132 and 3-methyladenine (3-MA) are used to detect the roles of 26S proteasome and autophagolysosome in expression levels of C protein. Truncated and mutant C proteins are used to find the exact residues responsible for the degradation of C protein. Immunoprecipitaion is performed to find whether C protein is ubiquitinated or not. Results C-EGFP protein expresses in a cleaved form at a low level and is degraded by 26S proteasome which could be partly inhibited by MG132. C-terminal residues play more important roles in the degradation of C protein than N-terminal residues. Residues 260 to 267, especially M260 and L261, are crucial for the degradation. In addition, C-terminal residues 262 to 267 determine cleavage efficiency of C protein. Conclusions CSFV C protein is degraded by 26S proteasome in a ubiquitin-independent manner. Last 8 residues at C-terminus of immature C protein play a major role in proteasomal degradation of CSFV C protein and determine the cleavage efficiency of C protein by signal peptide peptidase (SPP). Our findings provide valuable help for fully understanding degradation process of C protein and contribute to fully understanding the role of C protein in CSFV replication.

Diseases caused by Flaviviridae have a wide global and economic impact due to high morbidity and mortality. Flaviviridae infection usually leads to severe, acute or chronic diseases, such as liver injury and liver cancer resulting from hepatitis C virus (HCV) infection, dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS) caused by dengue virus (DENV). Given the highly complex pathogenesis of Flaviviridae infections, they are still not fully understood at present. Accumulating evidence suggests that host autophagy is disrupted to regulate the life cycle of Flaviviridae. Organelle-specific autophagy is able to selectively target different organelles for quality control, which is essential for regulating cellular homeostasis. As an important sub process of autophagy, lipophagy regulates lipid metabolism by targeting lipid droplets (LDs) and is also closely related to the infection of a variety of pathogenic microorganisms. In this review, we briefly understand the LDs interaction relationship with Flaviviridae infection, outline the molecular events of how lipophagy occurs and the related research progress on the regulatory mechanisms of lipophagy in Flaviviridae infection. Exploring the crosstalk between viral infection and lipophagy induced molecular events may provide new avenues for antiviral therapy.

Highly enantioselective synthesis of allenes has been relying, so far, on the steric hindrance of substrates. Here the authors achieve excellent stereocontrol in the synthesis of chiral allenes with a palladium-DTBM-SEGPHOS catalytic system in a non-substrate-dependent manner.

Intestinal microbiota dysregulation is considered the primary trigger of low-grade inflammation responsible for weight loss due to heat stress. 1,8-Cineole is the major bacteriostatic agent in eucalypt and possesses remarkable anti-inflammatory properties. However, the mechanisms of its effect on intestinal microbiota remain unclear. In this study, 1,8-cineole was prepared into microcapsules prior to use as feed supplement in chickens. The microencapsulation efficiency and chemical stability of 1,8-cineole microcapsules were evaluated. The chicken treatment with 1,8-cineole microcapsules (1 or 3%) for 45 days, in the presence or absence of heat stress for fifteen days, commenced on Day 31, with or without an antibiotics mix (Abx) for three days on Day 27. Performance parameters were measured once a week from Day 30 through Day 45. Surface and entrapped concentration of 1,8-cineole was estimated as 7.89 g/100 g powder in the microcapsules. The time to maximal concentration (Tmax), terminal half-life (T1/2), and the area under plasma concentration-time curve (AUC0-t) of the encapsulated 1,8-cineole were higher than those of the nonencapsulated in treated chickens, although the maximal concentrations (Cmax) were similar. Chickens treated under higher temperatures with 1,8-cineole microcapsules exhibited lower levels of grade inflammation and higher body weight gain. Dietary 1,8-cineole microcapsules recovered the normal structure of upper ileum and altered the ratio of gut microbiota under heat stress and increased the ratio of Lactobacillus and Escherichia, whereas the proportion of Salmonella decreased based on 16S rRNA analysis of the upper ileum microbiota. In vitro, 1,8-cineole effectively inhibited the growth of Salmonella as demonstrated by inhibition zone assay. In summary, our findings elucidated the interaction between 1,8-cineole and intestinal microbiota as a new mechanism for the anti-heat stress effect of 1,8-cineole in preventing low-grade inflammation and weight loss. The results suggest that 1,8-cineole microcapsules may be a good feed supplement to protect against heat stress injury.

The 26S proteasome, in charge of intracellular protein degradation, plays significant roles in the modulation of various cellular activities as well as in the interplay between virus and host. However, studies about the relationship between 26S proteasome and classical swine fever virus (CSFV) is limited up to now. MG132 is a proteasome inhibitor and has been extensively used in studies about replication of many viruses. Herein, we investigated the role of MG132 in CSFV replication and results showed that MG132 significantly decreased virus titers and viral RNA copies in CSFV-infected PK-15 cells. Further studies demonstrated that MG132 upregulated the expression of several interferon-stimulated genes (ISGs), in CSFV-infected cells. Since the activation of ISGs is controlled by the JAK-STAT signal pathway, we next examined the effect of MG132 on the expression and localization of key molecular STAT1 in the infected cells using Western blot and confocal laser scanning microscopy, respectively. Results showed that CSFV infection and viral NS4A protein decreased the protein level of STAT1, and MG132 promoted the accumulation of STAT1 in the nucleus of cells adjacent to the CSFV-infected cells. Besides, MG132 did not affect the expressions of IFN-α, STAT1, Mx1, OAS1, and PKR genes in cells without CSFV. In conclusion, we identify that MG132 significantly inhibits CSFV replication in vitro, in which the activation of the JAK-STAT pathway and the subsequent upregulation of expressions of ISGs might play significant roles, providing a potential preventive method for CSF.

Viruses have evolved many mechanisms to escape host antiviral responses. Previously, we found that classical swine fever virus (CSFV) infection induces autophagy using the autophagosome as a self-replication site, thereby evading the host immune response and promoting long-term infection. However, the underlying mechanisms used by CSFV to enter autophagosomes and the mechanism by which autophagy promotes viral replication remain unclear. We found that CSFV infection inhibited autophagy receptor nuclear dot protein 52 kDa (NDP52) expression, ubiquitination, and SUMO2-4 modification. Further analyses revealed that CSFV mediated ubiquitination and SUMOylation of NDP52 via Pten-induced kinase 1 (PINK1)-Parkin. Moreover, NDP52 inhibition also inhibited CSFV replication and the induction of mitophagy marker proteins expression. Inhibition of NDP52 reduced CD63 expression and binding to CSFV E2 protein, which has an essential role in persistent CSFV infection. As NDP52 has a close relationship with the NF-κB innate immunity pathway and plays an important role in the antiviral response, we investigated whether NDP52 inhibited CSFV replication through the release of immune factors and antivirus signals. Our results showed that inhibiting NDP52 boosted interferon and TNF release and promoted NF-κB pathway activation. In summary, we found that NDP52 inhibition not only reduces CSFV binding and entry into autophagic vesicles, but also inhibits CSFV replication by active NF-κB antiviral immune pathways. Our data reveal a novel mechanism by which NDP52, an autophagy receptor, mediates CSFV infection, and provide new avenues for the development of antiviral strategies.

Lipids metabolism plays a significant role in cellular responses to virus pathogens. However, the impact of lipids metabolism in CSFV infection is not yet confirmed. In the present study, for the fist time, we performed serum lipidomics analysis of piglets infected with CSFV based on ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS), and identified 167 differentially expressed lipid metabolites. Interestingly, free fatty acids (FFAs) accumulated significantly in these metabolites, accompanied by an increase in sphingolipids and a decrease in glycerolipids and glycerophospholipids, suggesting that CSFV infection markedly changed the serum lipid metabolism of piglets. FFAs are the principal constituents of many complex lipids and are essential substrates for energy metabolism. Based on this, we focused on whether FFAs play a prominent role in CSFV infection. We found that CSFV infection induced FFAs accumulation in vivo and in vitro, which is due to increased fatty acid biosynthesis. Meanwhile, we discovered that alteration of cellular FFAs accumulation by a mixture of FFAs or inhibitors of fatty acid biosynthesis affects progeny virus production in vitro. Furthermore, in the absence of glucose or glutamine, CSFV still has replication capacity, which is significantly reduced with the addition of fatty acid beta oxidation inhibitors, suggesting that the process of FFAs enter the mitochondria for beta oxidation to produce ATP is necessary for virus replication. Finally, we demonstrated CSFV induced FFAs accumulation results in impaired type I IFN signaling-mediated antiviral responses by down-regulating RIG-I-like receptors (RLRs) signaling molecules, which may represent a mechanism of CSFV replication. Taken together, these findings provide the first data on lipid metabolites during CSFV infection and reveal a new view that CSFV infection requires FFAs to enhance viral replication.

Endoplasmic reticulum (ER) stress-mediated autophagy plays significant roles in replication and pathogenesis of many animal viruses. However, the relationship between ER stress, autophagy, and viral replication during in vivo and in vitro infection of classical swine fever virus (CSFV) remains unclear. In this study, we established a pig model for CSFV infection and found that viral loads of CSFV differed in 10 kinds of infected organs, and that the degree of tissue lesions was to some extent positively correlated with CSFV replication in vivo. Next, we found that CSFV infection not only induced ER stress and subsequently activated three unfolded protein responses (UPR) pathways including protein kinase R-like ER kinase (PERK), inositol requiring enzyme 1 (IRE1), and activating transcription factor-6 (ATF-6) pathways, but also triggered complete autophagy in main immune organs and partial nonimmune organs exhibiting severer pathological injuries and higher viral loads. However, only the IRE1 pathway and no autophagy were activated in some other nonimmune organs with slighter pathologies and lower viral loads. These results indicate a potential link between CSFV-induced ER stress and autophagy, both of which are associated with the CSFV replication in vivo. We further performed in vitro experiments and found that CSFV infection activates the PERK and IRE1 pathways and autophagy in cultured porcine kidney cell lines (PK-15) and macrophage cell lines (3D4/2), and pharmacological regulation of ER stress remarkably changed autophagic activities induced by CSFV, suggesting that CSFV-induced autophagy can be mediated by ER stress possibly via the PERK and IRE1 pathway. Furthermore, treatment with ER stress regulators significantly altered copy numbers of NS5B genes, expression of Npro proteins, and viral titers in CSFV-infected cells or in cells treated with autophagy regulators prior to CSFV infection, suggesting the requirement of ER stress-mediated autophagy for CSFV replication in vitro. Collectively, our data demonstrate that CSFV induces ER stress-mediated autophagy to sustain its replication in vivo and in vitro, which may be one of the potential strategies exploited by CSFV for immune evasion. This finding will provide new insights into mechanisms of replication and pathogenesis of CSFV, and development of new strategies for controlling CSF.

Gamma-butyrolactones are widespread in Nature, however direct catalytic methods to access them are limited. Here, the authors report a gold-catalyzed cycloisomerization of allenoic acids to acces γ-butyrolactones and apply it to the asymmetric synthesis of xestospongienes E, F, G, and H and other naturally occurring lactones.

Porcine circovirus associated diseases (PCVAD) is a contagious disease of swine caused by porcine circovirus type 2 (PCV2). The capsid protein (Cap) is the sole structural protein and the main antigen of PCV2. Cap is the principal immunogenic protein and induces humoral and cellular immunity. CD154 and GM-CSF are immune adjuvants that enhance responses to vaccines. However, whether these two cellular molecules could produce an enhanced effect in PCV2 vaccines still needs to be further studied. The results of PCR and restriction enzyme showed that the recombinant lentiviral plasmids pCDH-TB-Cap, pCDH-TB-Cap-CD154 and pCDH-TB-Cap were successfully constructed. Western blot and IFA showed that the three fusion proteins TB-Cap, TB-Cap-CD154 and TB-Cap-GM-CSF were stably expressed in CHO-K1 cells. Indirect ELISA assay showed that mice immunized with TB-Cap-CD154 and TB-Cap-GM-CSF fusion proteins produced higher PCV2-specific antibodies than mice immunized with the TB-Cap and a commercial vaccine (p < 0.0001). Moreover, lymphocyte proliferation and flow cytometry showed that the cellular immune response of each immune group was significantly enhanced (p < 0.0001). After PCV2 challenge, the results revealed that the viral loads in serum, lung and kidney of all vaccinated groups were significantly lower than the PBS group (p < 0.0001). The transcription levels of IL-2, IFN-gamma, IL-4 and IL-10 cytokines in the TB-Cap, TB-Cap-CD154 and TB-Cap-GM-CSF groups were significantly higher than those in the PBS and recombinant vaccine groups (p < 0.0001). These results indicated that CD154 and GM-CSF could enhance the ability of TB-Cap protein to induce the body to produce PCV2 specific antibodies and increase the transcription level of cytokines. Thus, CD154 and GM-CSF molecules were a powerful immunoadjuvant for PCV2 subunit vaccines. The novel TB-Cap-CD154 and TB-Cap-GM-CSF subunit vaccine has the potential to be used for the prevention and control of PCVAD.

Formation of vicinal, quaternary stereocentres is challenging, but such products are commonly encountered in nature. Here, the authors report a palladium catalysed process to form vicinal quaternary carbons via propargylation, including in enantiopure form when optically active starting materials are employed.

Autophagy is a general protective mechanism for maintaining homeostasis in eukaryotic cells, regulating cellular metabolism, and promoting cell survival by degrading and recycling cellular components under stress conditions. The degradation pathway that is mediated by autophagy receptors is called selective autophagy, also named as xenophagy. Autophagy receptor NDP52 acts as a ‘bridge’ between autophagy and the ubiquitin-proteasome system, and it also plays an important role in the process of selective autophagy. Pathogenic microbial infections cause various diseases in both humans and animals, posing a great threat to public health. Increasing evidence has revealed that autophagy and autophagy receptors are involved in the life cycle of pathogenic microbial infections. The interaction between autophagy receptor and pathogenic microorganism not only affects the replication of these microorganisms in the host cell, but it also affects the host’s immune system. This review aims to discuss the effects of autophagy on pathogenic microbial infection and replication, and summarizes the mechanisms by which autophagy receptors interact with microorganisms. While considering the role of autophagy receptors in microbial infection, NDP52 might be a potential target for developing effective therapies to treat pathogenic microbial infections.

A protocol has been developed to prepare 1,2-allenyl ketones using molecular oxygen in air or pure oxygen as the oxidant from 2,3-allenylic alcohols with moderate to good yields under mild conditions. In this reaction CuCl (20 mol %) with 1,10-phenanthroline (10 mol %) and bipyridine (10 mol %) was used as the catalyst. It is interesting to observe that the use of the mixed ligands is important for the higher yields of this transformation: With the monoligand approach developed by Markó et al., the yields are relatively lower.

An efficient route to prepare 4-(1',3'-dien-2'-yl)-2,5-dihydrofuran derivatives based on homodimeric coupling cyclization reaction of 2,3-allenols in presence of Pd[Cl.sub.2]/NaI as catalyst is reported.

A new functionalization of indoles through the Pd[(OAc).sub.2]-catalyzed reaction of indoles with 2-acetoxymethyl-substituted electron-deficient alkenes to afford 3-(2-methoxycarbonyl-2-propenyl)indoles in which [beta]-OAc functional group was used for the regeneration of Pd(II) species is reported. It was found that for N-protected indoles the reaction proceeded smoothly in the presence of 5 mol % of Pd[(acac).sub.2] and 10 mol % of PP[h.sub.3] at 80 degree Celsius in HOAc, while for N-unprotected indoles, the reaction was carried out by using 5 mol % of Pd[(dba).sub.2] or 2.5 mol % of P[d.sub.2][(dba).sub.3]-CHC[l.sub.3] with 10 mol % of 2,2'-bipyridine as the catalyst in toluene.

A highly regioselective Cu(I)-catalyzed anti-carbometallation of secondary terminal propargylic alcohols with 1 degree alkyl or aryl Grignard reagents affording 2-substituted allylic alcohols was developed. By using this method, optically active allylic alcohols is prepared from optically active propargylic alcohols without obvious loss of the enantiopurity.

Four cationic palladium intermediates are characterized by the high-resolution ESI-FTMS technology. It provides direct evidence for the mechanism of Pd(0)-catalyzed three dimensional component tandem double addition cyclization of organic halides, 2-(2,3-allenyl)malonates and imines.

A highly stereoselective iodolactonization of alkylidenecyclopropyl esters with iodine or N-iodosuccinimide (NIS) in aqueous CH3CN to afford 4,5-trans-1,5-cis-3-oxabicyclo[3.1.0]hexane-2-ones is described. The stereoselectivity might be controlled by the steric effects of the substituent group of the C=C bond.

A good regio- and selectivity was observed for the PdCl2-catalyzed cyclocarbonylation of 2-alkynols with CuCl2 affording (Z)-alpha-chloroalkylidene-beta-lactones. The Pd(II)-catalyzed cyclocarbonylation of 2-alkynols with CuBr2 was also studied.

A report is presented on the results of the PdCl2-catalyzed cyclocarbonylation of propargylic amines affording (E)-alpha-chloroalkylidene-beta-lactams highly selectively. The reaction of the readily available optically active propargylic amines provides a convenient synthesis of the corresponding (E)-alpha-chloroalkyl-beta-lactams with high ee values.

The halohydroxylation of 1,2-allenyl sulfides or selenides with Br(sub 2) (CuBr(sub 2) or NBS) or I(sub 2) and water demonstrate a fair good regioselectivity leading to the synthesis of synthetically important 3-organosulfur or seleno-2-haloallylic alcohols. The conclusion states that the stereoselectivity depends on the nature of X(super +) and S or Se, showing a Z-selectivity with the matched Lewis acid-base pair.

Main observation and conclusion: Allenes and oxindoles are two classes of very important compounds for medicinal chemistry and organic chemistry. Thus, it is of high interest to combine an allene and an oxindole into one molecule. Herein, the first example of palladium‐catalyzed exclusive 2,3‐allenylation reaction of oxindoles with 2,3‐allenylic carbonates has been successfully developed. A rationale for the selectivity of 2,3‐allenylation over the expected 1,3‐alkadienylation has been proposed. [ABSTRACT FROM AUTHOR]

Research has been conducted on 1,3,5-tribromo-2,4,6-trienylbenzenes. The synthesis of these compounds has been carried out via amination, alkylation and etherification methods and the details are presented.

Research has been conducted on the allene chemistry. The results of the palladium(0)-catalyzed coupling-cyclization of 2,3-allenamides and organic iodides are presented.

Research has been conducted on the palladium(II) catalysts. The ability of these catalysts to catalyze the coupling reactions of 2,3- and 3,4-allenols with allylic halides in DMA in producing 2,5-dihydrofurans and 5,6-dihydro-2H-pyrans has been investigated and discussed.

The organozinc reagent coupling reactions with alkenyl halides, showing both pathway I- and pathway II-type regiochemistry, are described. Results reveal two coupling patterns for the palladium(0)-catalyzed reaction of allenic/propargylic zinc reagents with organic halides. Data indicate that the regioselectivity of the coupling reaction depends on both organic halide structure and 1-arylalk-1-ynes.

Research has been conducted on the preparation of beta-halobutenolides. Results indicate that they can be prepared by CuX (sub)2-mediated halolactonization reaction of 2,3-allenoic acids.

A methodology was presented which offers an efficient general high-yielding route to beta, gamma-unsaturated beta-haloketones with different substitution patterns. It makes use of a finding that 3,4-pentadien-2-one's hydrohalogenation reaction with metal halides in HOAc at room temperature selectively afforded 4-halo-4-penten-2-ones in high yields. It possesses utility in the organic synthesis of coumpounds such as homoallylic alcohols and substituted beta, gamma-unsaturated enones.

A study was conducted to determine the type of stereoinduction which would be manifested on the configuration of the carbon atom at the alpha-methyl-gamma-butyrolactone ring beta-position after a substitution is made at the 1'-position of the 2'alkenyl group. Beta,gamma-disubstituted alpha-(Z)-(chloromethylene)-gamma-butyrolactone derivatives were synthesized using a method involving Pd(II)-catalyzed 4'-halo-2'-alkenyl 2-alkynoate cyclization. Stereochemical results are presented and analyzed.

The palladium(II)-catalyzed cyclization of acyclic 2'-alkenyl-2-alkynoates in the presence of cupric chloride provides an efficient stereoeselective route to alpha-(chloromethylene)-gamma-butyrolactones. The process involves the formation of a chloropalladium species, followed by insertion of an olefinic bond to the carbon-palladium bond. Cupric chloride then induces the formation of the C-Cl bond. The stereochemical mechanism is also discussed.

Main observation and conclusion: The first example of Rh‐catalyzed kinetic resolution of 1,3‐disubstituted allene‐1,3‐dienes involving intramolecular [4+2]‐cycloaddition has been developed. Followed by C=C isomerization, the reaction finally afforded aza‐[4.3.0]bicyclic compounds with a very high enantio‐ and E‐selectivity. The mechanism has been unveiled by careful control experiments. The synthetic potentials of highly enantioenriched bicyclic products have also been demonstrated. [ABSTRACT FROM AUTHOR]

An efficient monofluorination method is developed to synthesize [beta]-fluorobutenolides. The process involves the electrophilic fluorocycliziation of 2,3-allenoic acids with selectfluor in MeCN in the presence of 10 equiv of [H.sub.2]O or pure water.

An electrophilic interaction was developed of 2,3-allenoates with PhSeCl affording 3-phenylseleno-4-oxo-2(E)-alkenoates in good yields and excellent regio- and stereo-selectivity. Although the amount of water in air and commercially available MeCN might be very different, the reaction might be easily reproduced by using anhydrous MeCN under [N.sub.2] with the addition of a specified amount of water.

The Sonogashira coupling of 3-iodoalk-2-en-1-ols in presence of iodine with terminal propargyl alcohols to form 4-alkyn-2-ene-1,6-diols is described. The results revealed that different alkyl or aryl groups could be introduced into different positions of furans due to the substituent-loading capability of 3-iodoalkenols and diversity of the terminal propargyl alcohols and allylic bromides.

Zn[I.sub.2] is identified as the catalyst for the one-step synthesis of allenes from terminal alkynes and aldehydes with morpholine as the base in toluene. The reaction has proceeded via the intermediacy of propargylic amines and it is applicable for both aromatic and aliphatic aldehydes.