Interspecies/Intergroup Complementation of Orthotospovirus Replication and Movement through Reverse Genetics Systems.

Orthotospoviruses, the plant-infecting bunyaviruses, cause serious diseases in agronomic crops and pose major threats to global food security. The family of Tospoviridae contains more than 30 members that are classified into two geographic groups, American-type and Euro/Asian-type orthotospovirus. However, the genetic interaction between different species and the possibility, during mixed infections, for transcomplementation of gene functions by orthotospoviruses from different geographic groups remains underexplored. In this study, minireplicon-based reverse genetics (RG) systems have been established for Impatiens necrotic spot virus (INSV) (an American-type orthotospovirus) and for Calla lily chlorotic spot virus and Tomato zonate spot virus (CCSV and TZSV) (two representative Euro/Asian orthotospoviruses). Together with the earlier established RG system for Tomato spotted wilt virus (TSWV), a type species of the Orthotospovirus American-clade, viral replicase/movement proteins were exchanged and analyzed on interspecies transcomplementation. Whereas the homologous RNA-dependent RNA polymerase (RdRp) and nucleocapsid (N) protein supported the replication of orthotospoviruses from both geographic groups, heterologous combinations of RdRp from one group and N from the other group were unable to support the replication of viruses from both groups. Furthermore, the NSm movement protein (MP), from both geographic groups of orthotospoviruses, was able to transcomplement heterologous orthotospoviruses or a positive-strand Cucumber mosaic virus (CMV) in their movement, albeit with varying efficiency. MP from Rice stripe tenuivirus (RSV), a plant-infecting bunyavirus that is distinct from orthotospoviruses, or MP from CMV also moves orthotospoviruses. Our findings gain insights into the genetic interaction/reassortant potentials for the segmented plant orthotospoviruses. IMPORTANCE Orthotospoviruses are agriculturally important negative-strand RNA viruses and cause severe yield-losses on many crops worldwide. Whereas the emergence of new animal-infecting bunyaviruses is frequently associated with genetic reassortants, this issue remains underexposed with the plant-infecting orthotospovirus. With the development of reverse genetics systems for orthotospoviruses from different geographic regions, the interspecies/intergroup replication/movement complementation between American- and Euro/Asian-type orthotospoviruses were investigated. Genomic RNAs from American orthotospoviruses can be replicated by the RdRp and N from those of Euro/Asia-group orthotospoviruses, and vice versa. However, their genomic RNAs cannot be replicated by a heterologous combination of RdRp from one geographic group and N from another geographic group. Cell-to-cell movement of viral entity is supported by NSm from both geographic groups, with highest efficiency by NSm from viruses belonging to the same group. Our findings provide important insights into the genetic interaction and exchange ability of viral gene functions between different species of orthotospovirus.

Natural Occurrence of cowpea mild mottle virus infecting sesame (Sesamum indicum L.) in Anhui Province, China.

Sesame (Sesamum indicum L.) is one of the primary oilseed crops in China, and often intercropped with shorter crops like peanuts and soybeans. Cowpea mild mottle virus (CpMMV), a member of the Betaflexiviridae family, has been reported in numerous countries worldwide and can infect natural hosts including cowpeas, soybeans, common beans, peanuts, and tomatoes, causing symptoms such as leaf mottling, mosaic patterns, or spotted patterns on the infected leaves. CpMMV is transmitted by whiteflies in nature and by mechanical inoculation in laboratory settings (Iwaki et al., 1982). In September 2023, while surveying soybean virus diseases in Huang-Huai-Hai region of China, we observed sesame plants near a soybean field (longitude 115.76°E, latitude 32.89°N) showing stunted growth, leaf mottling, and mosaic patterns. These symptoms affected approximately one-third of the sesame plants in a 0.1-hectare field. To identify the virus associated with symptomatic leaves, two sesame samples were collected for small RNA deep sequencing. Total RNA was extracted using TRIZOL and sent to BGI for library construction and sequencing with the BGISEQ-500 sequencer. De novo assembly of sRNA reads was performed using Velvet software (version 1.2.10) as described (Su et al., 2016), followed by BLASTn and BLASTx searches against the nonredundant nucleotide and protein databases. CpMMV was identified from sesame plants, with twenty-three contigs ranging from 51 to 368 nucleotides showing similarity to CpMMV, covering 33.7% of the total CpMMV genome. The largest CpMMV contig, spanning 368 nucleotides (nt), exhibited 97% identity to CpMMV isolate Anhui_SZ_DN1383 (Genbank Accession No. MN908944.1) from soybean (Wei et al., 2020). To validate the presence of CpMMV in sesame, RNA from each sample was individually extracted, and CpMMV was detected by reverse-transcription polymerase chain reaction (RT-PCR) according to the manufacturer's instructions (Vazyme, Nanjing, China). Primers were designed based on two small RNA-assembled contigs spanning the CpMMV triple gene block protein 1 (TGBp1) and TGBp2 ORF (Forward: 5´-GGTACCAAAAGATAAGCTTGTTATCTTG-3´; Reverse: 5´-TTAGTACCGTCTCTGTAACAGCCA-3´). Both sesame samples tested RT-PCR positive for CpMMV. The PCR amplicon (597 nt) of these two sesame samples were purified and sequenced. Sequences shared 100% nucleotide identity between them. Nucleotide sequence comparisons confirmed the virus as CpMMV (Accession No. PP767740), exhibiting >99% identity to CpMMV isolate HN_SQ (MW354940.1). Phylogenetic analysis of the 597 nt amplicon, using MEGA7 with eighteen other CpMMV isolates, revealed that the CpMMV isolate from sesame was most closely related to soybean isolates HN_SQ (MW354940.1) and Anhui_SZ_DN1383 (MN908944.1). To fulfill Koch's postulates, healthy sesame leaves were rub-inoculated with crude extracts from CpMMV-infected field samples. RT-PCR confirmed systemic infection at 4 weeks post-inoculation, with symptoms of stunted height, leaf mottle, and mosaic mirroring those observed in the field. Previously, CpMMV has been experimentally documented to infect sesame (Thouvenel et al., 1982), but to our best knowledge, this is the first report of CpMMV infecting sesame under natural conditions. With widespread whiteflies in the Huang-Huai-Hai region of China, CpMMV poses a significant risk to sesame production and may serve as a reservoir, threatening nearby crops such as soybeans.

Rescue of tomato spotted wilt virus entirely from complementary DNA clones.

Negative-stranded/ambisense RNA viruses (NSVs) include not only dangerous pathogens of medical importance but also serious plant pathogens of agronomic importance. Tomato spotted wilt virus (TSWV) is one of the most important plant NSVs, infecting more than 1,000 plant species, and poses major threats to global food security. The segmented negative-stranded/ambisense RNA genomes of TSWV, however, have been a major obstacle to molecular genetic manipulation. In this study, we report the complete recovery of infectious TSWV entirely from complementary DNA (cDNA) clones. First, a replication- and transcription-competent minigenome replication system was established based on 35S-driven constructs of the S(-)-genomic (g) or S(+)-antigenomic (ag) RNA template, flanked by the 5' hammerhead and 3' ribozyme sequence of hepatitis delta virus, a nucleocapsid (N) protein gene and codon-optimized viral RNA-dependent RNA polymerase (RdRp) gene. Next, a movement-competent minigenome replication system was developed based on M(-)-gRNA, which was able to complement cell-to-cell and systemic movement of reconstituted ribonucleoprotein complexes (RNPs) of S RNA replicon. Finally, infectious TSWV and derivatives carrying eGFP reporters were rescued in planta via simultaneous expression of full-length cDNA constructs coding for S(+)-agRNA, M(-)-gRNA, and L(+)-agRNA in which the glycoprotein gene sequence of M(-)-gRNA was optimized. Viral rescue occurred with the addition of various RNAi suppressors including P19, HcPro, and γb, but TSWV NSs interfered with the rescue of genomic RNA. This reverse genetics system for TSWV now allows detailed molecular genetic analysis of all aspects of viral infection cycle and pathogenicity.

Traffic Signal Timing Optimization Model Based on Video Surveillance Data and Snake Optimization Algorithm.

With the continued rapid growth of urban areas, problems such as traffic congestion and environmental pollution have become increasingly common. Alleviating these problems involves addressing signal timing optimization and control, which are critical components of urban traffic management. In this paper, a VISSIM simulation-based traffic signal timing optimization model is proposed with the aim of addressing these urban traffic congestion issues. The proposed model uses the YOLO-X model to obtain road information from video surveillance data and predicts future traffic flow using the long short-term memory (LSTM) model. The model was optimized using the snake optimization (SO) algorithm. The effectiveness of the model was verified by applying this method through an empirical example, which shows that the model can provide an improved signal timing scheme compared to the fixed timing scheme, with a decrease of 23.34% in the current period. This study provides a feasible approach for the research of signal timing optimization processes.

Development of a Mini-Replicon-Based Reverse-Genetics System for Rice Stripe Tenuivirus.

Negative-stranded RNA (NSR) viruses include both animal- and plant-infecting viruses that often cause serious diseases in humans and livestock and in agronomic crops. Rice stripe tenuivirus (RSV), a plant NSR virus with four negative-stranded/ambisense RNA segments, is one of the most destructive rice pathogens in many Asian countries. Due to the lack of a reliable reverse-genetics technology, molecular studies of RSV gene functions and its interaction with host plants are severely hampered. To overcome this obstacle, we developed a mini-replicon-based reverse-genetics system for RSV gene functional analysis in Nicotiana benthamiana. We first developed a mini-replicon system expressing an RSV genomic RNA3 enhanced green fluorescent protein (eGFP) reporter [MR3(-)eGFP], a nucleocapsid (NP), and a codon usage-optimized RNA-dependent RNA polymerase (RdRpopt). Using this mini-replicon system, we determined that RSV NP and RdRpopt are indispensable for the eGFP expression from MR3(-)eGFP. The expression of eGFP from MR3(-)eGFP can be significantly enhanced in the presence of four viral suppressors of RNA silencing (VSRs), NSs, and P19-HcPro-γb. In addition, NSvc4, the movement protein of RSV, facilitated eGFP trafficking between cells. We also developed an antigenomic RNA3-based replicon in N. benthamiana. However, we found that the RSV NS3 coding sequence acts as a cis element to regulate viral RNA expression. Finally, we made mini-replicons representing all four RSV genomic RNAs. This is the first mini-replicon-based reverse-genetics system for monocot-infecting tenuivirus. We believe that the mini-replicon system described here will allow studies of the RSV replication, transcription, cell-to-cell movement, and host machinery underpinning RSV infection in plants. IMPORTANCE Plant-infecting segmented negative-stranded RNA (NSR) viruses are grouped into three genera: Orthotospovirus, Tenuivirus, and Emaravirus. Reverse-genetics systems have been established for members of the genera Orthotospovirus and Emaravirus. However, there is still no reverse-genetics system available for Tenuivirus. Rice stripe virus (RSV) is a monocot-infecting tenuivirus with four negative-stranded/ambisense RNA segments. It is one of the most destructive rice pathogens and causes significant damage to the rice industry in Asian countries. Due to the lack of a reliable reverse-genetics system, molecular characterizations of RSV gene functions and the host machinery underpinning RSV infection in plants are extremely difficult. To overcome this obstacle, we developed a mini-replicon-based reverse-genetics system for RSV in Nicotiana benthamiana. This is the first mini-replicon-based reverse-genetics system for tenuivirus. We consider that this system will provide researchers a new working platform to elucidate the molecular mechanisms dictating segmented tenuivirus infections in plants.

Comparison of Properties of Poly(Lactic Acid) Composites Prepared from Different Components of Corn Straw Fiber.

In recent years, under the pressure of resource shortage and white pollution, the development and utilization of biodegradable wood-plastic composites (WPC) has become one of the hot spots for scholars' research. Here, corn straw fiber (CSF) was chosen to reinforce a poly(lactic acid) (PLA) matrix with a mass ratio of 3:7, and the CSF/PLA composites were obtained by melt mixing. The results showed that the mechanical properties of the corn straw fiber core (CSFC) and corn straw fiber skin (CSFS) loaded PLA composites were stronger than those of the CSFS/PLA composites when the particle size of CSF was low. The tensile strength and bending strength of CSFS/CSFC/PLA are 54.08 MPa and 87.24 MPa, respectively, and the elongation at break is 4.60%. After soaking for 8 hours, the water absorption of CSF/PLA composite reached saturation. When the particle size of CSF is above 80 mesh, the saturated water absorption of the material is kept below 7%, and CSF/PLA composite has good hydrophobicity, which is mainly related to the interfacial compatibility between PLA and CSF. By observing the microstructure of the cross section of the CSF/PLA composite, the research found that the smaller the particle size of CSF, the smoother the cross section of the composite and the more unified the dispersion of CSF in PLA. Therefore, exploring the composites formed by different components of CSF and PLA can not only expand the application range of PLA, but also enhance the application value of CSF in the field of composites.

Cytoplasmic and nuclear Sw-5b NLR act both independently and synergistically to confer full host defense against tospovirus infection.

Plant intracellular nucleotide-binding leucine-rich repeat (NLR) receptors play critical roles in mediating host immunity to pathogen attack. We use tomato Sw-5b::tospovirus as a model system to study the specific role of the compartmentalized plant NLR in dictating host defenses against the virus at different infection steps. We demonstrated here that tomato NLR Sw-5b distributes to the cytoplasm and nucleus, respectively, to play different roles in inducing host resistances against tomato spotted wilt orthotospovirus (TSWV) infection. The cytoplasmic-enriched Sw-5b induces a strong cell death response to inhibit TSWV replication. This host response is, however, insufficient to block viral intercellular and long-distance movement. The nuclear-enriched Sw-5b triggers a host defense that weakly inhibits viral replication but strongly impedes virus intercellular and systemic movement. Furthermore, the cytoplasmic and nuclear Sw-5b act synergistically to dictate a full host defense of TSWV infection. We further demonstrated that the extended N-terminal Solanaceae domain (SD) of Sw-5b plays critical roles in cytoplasm/nucleus partitioning. Sw-5b NLR controls its cytoplasm localization. Strikingly, the SD but not coil-coil domain is crucial for Sw-5b receptor to import into the nucleus to trigger the immunity. The SD was found to interact with importins. Silencing both importin α and ß expression disrupted Sw-5b nucleus import and host immunity against TSWV systemic infection. Collectively, our findings suggest that Sw-5b bifurcates disease resistances by cytoplasm/nucleus partitioning to block different infection steps of TSWV. The findings also identified a new regulatory role of extra domain of a plant NLR in mediating host innate immunity.

Perioperative and long-term results of ultrasonography-guided single- and multiple-tract percutaneous nephrolithotomy for staghorn calculi.

BACKGROUND: It is possible that this condition will lead to urosepsis and progressive deterioration of renal function in the absence of surgical intervention. Several recent clinical studies have shown that multi-tract percutaneous nephrolithotomy (M-PCNL) has a similar stone free rate (SFR) as standard percutaneous nephrolithotomy (S-PCNL). As a result, M-PCNL was also recommended as a treatment option for staghorn calculi. AIM: To examine the perioperative and long-term results of ultrasonography-guided single- and M-PCNL. METHODS: This was a retrospective cohort study. Between March 2021 and January 2022, the urology department of our hospital selected patients for the treatment of staghorn calculi using percutaneous nephrolithotomy. The primary outcomes were complication rate and SFR, and the characteristics of patients, operative parameters, laboratory measurements were also collected. RESULTS: In total, 345 patients were enrolled in the study (186 in the S-PCNL group and 159 in the M-PCNL group). The SFR in the M-PCNL group was significantly higher than that in the S-PCNL group (P = 0.033). Moreover, the incidence rates of hydrothorax (P = 0.03) and postoperative infection (P = 0.012) were higher in the M-PCNL group than in the S-PCNL group. Logistic regression analysis demonstrated that post-operative white blood cell count (OR = 2.57, 95%CI: 1.90-3.47, P < 0.001) and stone size (OR = 1.59, 95%CI: 1.27-2.00, P < 0.001) were associated with a higher overall complication rate in the S-PCNL group. Body mass index (OR = 1.22, 95%CI: 1.06-1.40, P = 0.004) and stone size (OR = 1.70, 95%CI: 1.35-2.15, P < 0.001) were associated with increased overall complications in the M-PCNL group. CONCLUSION: Multiple access tracts can facilitate higher SFR while slightly increasing the incidence of acceptable complications.

Macrocyclization of 3-triflyloxybenzynes with tetrahydrofuran via an anionic thia-Fries rearrangement.

A novel and uncommon macrocyclization reaction between 3-triflyloxybenzynes and tetrahydrofuran has been developed for the first time, providing a direct method for the synthesis of a range of functionalized 19-membered polyether macrocycles in moderate to good yields. The process was proposed to proceed through an anionic thia-Fris rearrangement under transition metal-free conditions, leading to the formation of four new C-O bonds and one new C-S bond in a single step.

Direct Access to Trifluoromethyl-Substituted Carbamates from Carbon Dioxide via Copper-Catalyzed Cascade Cyclization of Enynes.

A copper-catalyzed cascade cyclization of enynes with Togni's reagent, carbon dioxide, and amines has been successfully developed. The reaction provides a direct and efficient route to a range of trifluoromethyl-substituted carbamates, which are difficult to access using existing methods. Mild reaction conditions, good functional tolerance, and wide substrate scope are the feactures of the protocol.

Iridium-Catalyzed Three-component Coupling Reaction of Carbon Dioxide, Amines, and Sulfoxonium Ylides.

The first iridium-catalyzed three-component coupling reaction of carbon dioxide, amines, and sulfoxonium ylides has been developed, providing an efficient and straightforward method for the construction of a range of structurally diverse O-ß-oxoalkyl carbamates in moderate to excellent yields. This novel protocol features the use of readily available substrates, wide substrate scope, and good functional group tolerance. Moreover, the phosgene-free strategy was successfully applied to the synthesis of a potential antitumor agent.

A Three-Phase Four-Component Coupling Reaction: Selective Synthesis of o-Chloro Benzoates by KCl, Arynes, CO2, and Chloroalkanes.

A transition-metal-free three-phase four-component coupling reaction (3P-4CR) involving KCl, arynes, chloroalkanes and CO2 has been reported for the first time, enabling the incorporation of both chloro and CO2 into an aryne simultaneously. The reactions for the synthesis of different types of o-chloro benzoates can be selectively modulated by the chloroalkane utilized. The corresponding products can be alternatively transformed for postsynthetic functionalizations conveniently.

A four-component coupling reaction of carbon dioxide, amines, cyclic ethers and 3-triflyloxybenzynes for the synthesis of functionalized carbamates.

A novel four-component coupling reaction of carbon dioxide, amines, cyclic ethers and 3-triflyloxybenzynes has been developed for the first time, providing an efficient method for the synthesis of a series of functionalized carbamate derivatives in moderate to high yields. The process proceeds under mild, transition metal-free and fluoride-free conditions, leading to the formation of two new C-O bonds, one new C-N bond and one C-H bond in a single step.