Female semiochemicals stimulate male courtship but dampen female sexual receptivity.

Chemical communication plays a vital role in mate attraction and discrimination among many insect species. Here, we document a unique example of semiochemical parsimony, where four chemicals act as both aphrodisiacs and anti-aphrodisiacs in different contexts in Bactrocera dorsalis. Specifically, we identified four female-specific semiochemicals, ethyl laurate, ethyl myristate, ethyl cis-9-hexadecenoate, and ethyl palmitate, which serve as aphrodisiacs to attract male flies and arouse male courtship. Interestingly, these semiochemicals, when sexually transferred to males during mating, can function as anti-aphrodisiacs, inhibiting the receptivity of subsequent female mates. We further showed that the expression of elongase11, a key enzyme involved in the biosynthesis of these semiochemicals, is under the control of doublesex, facilitating the exclusive biosynthesis of these four semiochemicals in females and guaranteeing effective chemical communication. The dual roles of these semiochemicals not only ensure the attractiveness of mature females but also provide a simple yet reliable mechanism for female mate discrimination. These findings provide insights into chemical communication in B. dorsalis and add elements for the design of pest control programs.

Nanoscale Visualization of Symmetry-Breaking Electronic Orders and Magnetic Anisotropy in a Kagome Magnet YMn6Sn6.

A kagome lattice hosts a plethora of quantum states arising from the interplay between nontrivial topology and electron correlations. The recently discovered kagome magnet RMn6Sn6 (R represents a rare-earth element) is believed to showcase a kagome band closely resembling textbook characteristics. Here, we report the characterization of local electronic states and their magnetization response in YMn6Sn6 via scanning tunneling microscopy measurements under vector magnetic fields. Our spectroscopic maps reveal a spontaneously trimerized kagome electronic order in YMn6Sn6, where the 6-fold rotational symmetry is disrupted while translational symmetry is maintained. Further application of an external magnetic field demonstrates a strong coupling of the YMn6Sn6 kagome band to the field, which exhibits an energy shift discrepancy under different field directions, implying the existence of magnetization-response anisotropy and anomalous g factors. Our findings establish YMn6Sn6 as an ideal platform for investigating kagome-derived orbital magnetic moment and correlated magnetic topological states.

Neuroprotection of Human Umbilical Cord-Derived Mesenchymal Stem Cells (hUC-MSCs) in Alleviating Ischemic Stroke-Induced Brain Injury by Regulating Inflammation and Oxidative Stress.

Brain injury caused by stroke has a high rate of mortality and remains a major medical challenge worldwide. In recent years, there has been significant attention given to the use of human Umbilical cord-derived Mesenchymal Stem Cells (hUC-MSCs) for the treatment of stroke in different adult and neonate animal models of stroke. However, using hUC-MSCs by systemic administration to treat ischemic stroke has not been investigated sufficiently. In this study, we conducted various experiments to explore the neuroprotection of hUC-MSCs in rats. Our findings demonstrate that an intravenous injection of a high dose of hUC-MSCs at 2 × 10^7 cells/kg markedly ameliorated brain injury resulting from ischemic stroke. This improvement was observed one day after inducing transient middle cerebral artery occlusion (MCAO) and subsequent reperfusion in rats. Notably, the efficacy of this single administration of hUC-MSCs surpassed that of edaravone, even when the latter was used continuously over three days. Mechanistically, secretory factors derived from hUC-MSCs, such as HGF, BDNF, and TNFR1, ameliorated the levels of MDA and T-SOD to regulate oxidative stress. In particular, TNFR1 also improved the expression of NQO-1 and HO-1, important proteins associated with oxidative stress. More importantly, TNFR1 played a significant role in reducing inflammation by modulating IL-6 levels in the blood. Furthermore, TNFR1 was observed to influence the permeability of the blood-brain barrier (BBB) as demonstrated in the evan's blue experiment and protein expression of ZO-1. This study represented a breakthrough in traditional methods and provided a novel strategy for clinical medication and trials.

Orientational Nanoconjugation with Gold Endows Marked Antimicrobial Potential and Drugability of Ultrashort Dipeptides.

Antibiotic resistance is a global threat. Antimicrobial peptides (AMPs) are highly desirable to treat multidrug-resistant pathogen infection. However, few AMPs are clinically available, due to high cost, instability, and poor selectivity. Here, ultrashort AMPs (2-3 residues with an N-terminal cysteine) are designed and assembled as gold nanoparticles. Au-S conjugation and ultrashort size restrict nonspecific reactions and peptide orientation, thus concentrating positively charged residues on the surface. The nanostructured assemblies enormously enhance antimicrobial abilities by 1000-6000-fold and stability. One representative (Au-Cys-Arg-NH2, Au_CR) shows selective antibacterial activity against Staphylococcus aureus with 10 nM minimal inhibitory concentration. Au_CR has comparable or better in vivo antimicrobial potency than vancomycin and methicillin, with low propensity to induce resistance, little side effects, and high stability (17.5 h plasma half-life). Au_CR acts by inducing collapse of membrane potential and rupture of the bacterial membrane. The report provides insights for developing AMP-metal nanohybrids, particularly tethering nonspecific reactions and AMP orientation on the metal surface.

Polarization-Sensitive Detector of Two-Dimensional Multilayer Hybrid Perovskite Crystals Showing High Polarization Ratio to Weak Light.

Two-dimensional (2D) hybrid perovskite materials have been widely used for polarization-sensitive photodetection due to their fascinating optical and physical attributes. However, studies on those materials that enable strong polarized-light activities under a weak-light condition remain quite scarce. Here, by tailoring aromatic cation into 3D prototype, we have successfully obtained a new 2D hybrid perovskite, (FPEA)2 (MA)Pb2 Br7 (1, where FPEA is 4-fluorophenethylammonium and MA is methylammonium). The alternative alignment of inorganic and organic structural components results in significant anisotropy, including optical absorption and electric conductivity. The coupling effect of these anisotropic properties in 1 gives rise to strong dichroic activities toward detecting polarized light. Especially, under weak light intensity (∼330 nW/cm2 ), it can still generate a large polarization ratio up to 1.35, which is even higher than those of some typical 2D materials (i. e., GeSe ∼1.09). Besides, single crystal-based photodetector of 1 displays fascinating detecting performances, including large photocurrent on/off ratio (∼104 ), fast response time (∼154/182 µs) and excellent antifatigued stability. These findings disclose the potentials of 1 as a robust candidate for detecting weak polarized light, which has practical applications in the field of polarized optoelectronics.

Enantioselective Synthesis of 2,3,3a,8a-Tetrahydrofuro[2,3-b]benzofuran Scaffolds Enabled by Cu(II)/SPDO-Catalyzed [3+2] Cycloaddition of 2,3-Dihydrofuran and Quinone Esters.

An asymmetric [3+2] cycloaddition of quinone esters with 2,3-dihydrofuran has been realized via a newly developed Cu(II)/SPDO complex. It provides straightforward access to 2,3,3a,8a-tetrahydrofuro[2,3-b]benzofurans (TFB) with high enantioselectivity (up to 97.5:2.5 er) and diastereoselectivity (all >20:1 dr). The resulting adducts contain two adjacent stereocenters and a continuously functionalized benzene ring. Additionally, this transformation could be easily performed on a gram scale, allowing for expedient synthesis of natural dihydroaflatoxin D2 and aflatoxin B2.

The response of ecosystem vulnerability to climate change and human activities in the Poyang lake city group, China.

Ecosystem vulnerability is an ecological response of the environment to external damage. Studying the influencing factors and spatiotemporal changes of ecosystem vulnerability is helpful to maintain ecological balance. At present, studies on ecosystem vulnerability are relatively homogeneous and rarely integrate climate change and human activities. Based on a habitat-function framework, this study analyzed the response of ecosystem vulnerability on climate change and human activities in the Poyang Lake City Group (PLCG) in 2010, 2015 and 2020. The spatial agglomeration of ecosystem vulnerability has been analyzed by using GeoDa model. The interaction of factors on ecosystem vulnerability have been analyzed by using geographical detector. It can be seen that the ecosystem vulnerability of the PLCG have increased from 2010 to 2020. The impacts of climate change to the ecosystem vulnerability have showed a positive correlation. Meanwhile, the key factors leading to the change of ecological vulnerability are still human activities. This methodology demonstrates a high level of robustness when applied to other research domains. This research is conducive to maintaining the integrity of the ecosystem, realizing the development of man and nature, and promoting the sound and rapid development of economic society.

Desorption of sulfamethoxazole from polyamide 6 microplastics: Environmental factors, simulated gastrointestinal fluids, and desorption mechanisms.

Microplastics (MPs) can enrich pollutants after being released into the environment, and the contaminants-loaded MPs are usually ingested by organisms, resulting in a potential dual biotoxic effect. In this paper, the adsorption behavior of Sulfamethoxazole (SMX) on Polyamide 6 (PA6) MPs was systematically investigated and simulated by the kinetic and isotherm models. The effect of environmental conditions (pH, salinity) on the adsorption process was studied, and the desorption behavior of SMX-loaded PA6 MPs was focused on simulating the seawater, ultrapure water, gastric and intestinal fluids. We found that lower pH and solubilization of SMX by gastrointestinal components (bovine serum albumin (BSA), sodium taurocholate (NaT), and pepsin) can reduce the electrostatic interaction between the surface charge of PA6 MPs and SMX. The result will lead to an increase in the desorption capacity of SMX-loaded PA6 MPs in gastrointestinal fluids and therefore will provide a reasonable mechanism for the desorption of SMX-loaded PA6 MPs in the gastrointestinal fluids. This study will provide a theoretical reference for studying the desorption behavior of SMX-loaded PA6 MPs under gastrointestinal conditions.

RNAi-mediated knockdown of α-Spectrin depresses reproductive performance in female Bactrocera dorsalis.

The female reproductive potential plays a crucial role in reproduction, population dynamics and population maintenance. However, the function of endogenous genes in undifferentiated germ cells has been largely unknown in Bactrocera dorsalis. In this study, the conservative analysis showed that α-Spectrin shared a similarity in B. dorsalis and other dipteral flies. Further, the differential expression of α-Spectrin was examined in B. dorsalis by RT-qPCR, and the expression pattern of α-Spectrin protein was identified in female adult ovaries by using immunostaining. During the development of ovary, the change on the number of undifferentiated germ cells was also characterized and analyzed. To understand the function of α-Spectrin in B. dorsalis ovary, the RNAi-based knockdown was conducted, and the RNAi efficiency was examined by RT-qPCR, western blot and bioassay. The results revealed that the α-Spectrin dsRNA could strikingly decrease the expression level of α-Spectrin in ovaries and diminish oviposition and ovary size as a consequence of downregulation of α-Spectrin. Overall, our study facilitates reproductive research on the function of conservative genes in B. dorsalis ovary, which may provide a new insight into seeking novel target genes for pest management control.

FSCN1 promotes proliferation, invasion and glycolysis via the IRF4/AKT signaling pathway in oral squamous cell carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a disease with increasing incidence worldwide that leads to deformity and death. In OSCC, fascin actin-bundling protein 1 (FSCN1) is an oncogene involved in the tumorigenesis process. However, the functions and potential mechanisms of FSCN1 in the OSCC tumorigenesis process have not been reported thus far. METHODS: We used qRT‒PCR to detect the expression of FSCN1 in 40 paired OSCC tumor tissues (tumor) and neighboring noncancerous tissues. The role of FSCN1 was also assessed in vitro through colony formation, CCK-8, and transwell assays. Moreover, glucose consumption was detected. Western blotting was used to confirm the interaction of FSCN1, IRF4 and AKT. RESULTS: FSCN1 was remarkably overexpressed in OSCC tissues and cell lines compared to corresponding controls. In addition, colony formation, CCK-8, and transwell assays revealed a notable reduction in OSCC growth and invasion when FSCN1 was silenced. FSCN1 silencing remarkably suppressed OSCC glycolysis. Mechanistic studies showed that FSCN1 achieves its function partially by activating interferon regulatory factor 4 (IRF4) and the AKT pathway in OSCC. CONCLUSION: In conclusion, our study investigated the functions and mechanisms of the FSCN1/IRF4/AKT pathway in OSCC progression. In OSCC, FSCN1 is likely to be a biomarker and therapeutic target.

Undocumented Migrants Reintroducing COVID-19, Yunnan Province, China.

To limit the spread of severe acute respiratory syndrome coronavirus 2, the government of China has been monitoring infected travelers and minimizing cold-chain contamination. However, other factors might contribute to recurring outbreaks. We analyze the role of undocumented migrants as potential transmitters of severe acute respiratory syndrome coronavirus 2 in China.

Topical review: recent progress of charge density waves in 2D transition metal dichalcogenide-based heterojunctions and their applications.

Charge density wave (CDW) is an intriguing physical phenomenon especially found in two-dimensional (2D) layered systems such as transition-metal dichalcogenides (TMDs). The study of CDW is vital for understanding lattice modification, strongly correlated electronic behaviors, and other related physical properties. This paper gives a review of the recent studies on CDW emerging in 2D TMDs. First, a brief introduction and the main mechanisms of CDW are given. Second, the interplay between CDW patterns and the related unique electronic phenomena (superconductivity, spin, and Mottness) is elucidated. Then various manipulation methods such as doping, applying strain, local voltage pulse to induce the CDW change are discussed. Finally, examples of the potential application of devices based on CDW materials are given. We also discuss the current challenge and opportunities at the frontier in this research field.

Topiramate, acupuncture, and BoNT-A for chronic migraine: a network meta-analysis.

BACKGROUND: Botulinum neurotoxin A (BoNT-A) was the primary choice for preventive treatment of chronic migraine. Topiramate and acupuncture showed promising effect for chronic migraine, but their effectiveness relative to BoNT-A was rarely studied. We aimed to perform a network meta-analysis to compare the effectiveness and acceptability between topiramate, acupuncture, and BoNT-A. METHODS: We searched OVID Medline, Embase, the Cochrane register of controlled trials (CENTRAL), the Chinese Clinical Trial Register, and clinicaltrials.gov for randomized controlled trials (RCTs) that compared topiramate, acupuncture, and BoNT-A with any of them or placebo in the preventive treatment of chronic migraine. A network meta-analysis was performed by using a frequentist approach and a random-effects model. The primary outcomes were reduction in monthly headache days and monthly migraine days at week 12. Acceptability was defined as the number of dropouts owing to adverse events. RESULTS: We included 15 RCTs (n = 2545). Eleven RCTs were at low risk of bias. The network meta-analyses (n = 2061) showed that acupuncture (2061 participants; standardized mean difference [SMD] -1.61, 95% CI: -2.35 to -0.87) and topiramate (582 participants; SMD -0.4, 95% CI: -0.75 to -0.04) ranked the most effective in the reduction of monthly headache days and migraine days, respectively; but they were not significantly superior over BoNT-A. Topiramate caused the most treatment-related adverse events and the highest rate of dropouts owing to adverse events. CONCLUSIONS: Topiramate and acupuncture were not superior over BoNT-A; BoNT-A was still the primary preventive treatment of chronic migraine. Large-scale RCTs with direct comparison of these three treatments are warranted to verified the findings.

Deficiency of X-ray repair cross-complementing group 1 in primordial germ cells contributes to male infertility.

X-ray repair cross-complementing group 1 (Xrcc1), a key DNA repair gene, plays a vital role in maintaining genomic stability and is highly expressed in the early stages of spermatogenesis, but the exact functions remain elusive. Here we generated primordial germ cell-specific Xrcc1 knockout (cXrcc1-/-) mice to elucidate the effects of Xrcc1 on spermatogenesis. We demonstrated that Xrcc1 deficiency results in infertility in male mice due to impaired spermatogenesis. We found that cXrcc1-/- mice exhibited smaller size of testes as well as lower sperm concentration and motility than the wild-type mice. Mechanistically, we demonstrated that Xrcc1 deficiency in primordial germ cells induced elevated levels of reactive oxygen species, mitochondria dysfunction, apoptosis, and loss of stemness of spermatogonial stem cells (SSCs) in testes. In Xrcc1-deficienct SSCs, elevated oxidative stress and mitochondrial dysfunction could be partially reversed by treatment with the antioxidant N-acetylcysteine (NAC), whereas NAC treatment did not restore the fertility or ameliorate the apoptosis caused by loss of Xrcc1. Overall, our findings provided new insights into understanding the crucial role of Xrcc1 during spermatogenesis.-Xu, C., Xu, J., Ji, G., Liu, Q., Shao, W., Chen, Y., Gu, J., Weng, Z., Zhang, X., Wang, Y., Gu, A. Deficiency of X-ray repair cross-complementing group 1 in primordial germ cells contributes to male infertility.

Emergence of human avian influenza A(H7N9) virus infections in Wenshan City in Southwest China, 2017.

BACKGROUND: The emergence of human infection with avian influenza A(H7N9) virus was reported in Wenshan City, southwestern China in 2017. The study describes the epidemiological and virological features of the outbreak and discusses the origin of the infection. METHODS: Poultry exposure and timelines of key events for each patient were collected. Samples derived from the patients, their close contacts, and environments were tested for influenza A(H7N9) virus by real-time reverse transcription polymerase chain reaction. Genetic sequencing and phylogenetic analysis were also conducted. RESULTS: Five patients were reported in the outbreak. An epidemiological investigation showed that all patients had been exposed at live poultry markets. The A(H7N9) isolates from these patients had low pathogenicity in avian species. Both epidemiological investigations of chicken sources and phylogenetic analysis of viral gene sequences indicated that the source of infection was from Guangxi Province, which lies 100 km to the east of Wenshan City. CONCLUSIONS: In the study, a sudden emergence of human cases of H7N9 was documented in urban area of Wenshan City. Chickens were an important carrier in the H7N9 virus spreading from Guangxi to Wenshan. Hygienic management of live poultry markets and virological screening of chickens transported across regions should be reinforced to limit the spread of H7N9 virus.

Characterizing potential repelling volatiles for "push-pull" strategy against stem borer: a case study in Chilo auricilius.

BACKGROUND: Massive techniques have been evaluated for developing different pest control methods to minimize fertilizer and pesticide inputs. As "push-pull" strategy utilizes generally non-toxic chemicals to manipulate behaviors of insects, such strategy is considered to be environmentally friendly. "Push-pull" strategy has been extraordinarily effective in controlling stem borers, and the identification of new "pushing" or "pull" components against stem borers could be significantly helpful. RESULTS: In this study, the results of field trapping assay and behavioral assay showed the larvae of C.auricilius, one kind of stem borers, could be deterred by rice plant under tilling stage, its main host crop. The profiles of volatiles were compared between rice plants under two different developmental stages, and α-pinene was identified as a key differential component. The repelling activity of α-pinene against C.auricilius was confirmed by Y-tube olfactometer. For illuminating the olfactory recognition mechanism, transcriptome analysis was carried out, and 13 chemosensory proteins (CSPs) were identified in larvae and 19 CSPs were identified in adult of C.auriciliu, which was reported for the first time in this insect. Among these identified CSPs, 4 CSPs were significantly regulated by α-pinene treatment, and CSP8 showed good binding affinity with α-pinene in vitro. CONCLUSIONS: Overall, C.auricilius could be repelled by rice plant at tilling stage, and our results highlighted α-pinene as a key component in inducing repelling activity at this specific stage and confirmed the roles of some candidate chemosensory elements in this chemo-sensing process. The results in this study could provide valuable information for chemosensory mechanism of C.auricilius and for identification of "push" agent against rice stem borers.

Purification and characterization of a new xylanase with excellent stability from Aspergillus flavus and its application in hydrolyzing pretreated corncobs.

A new extracellular xylanase was purified from a non-toxic mesophilic fungus Aspergillus flavus, and characterized as the ß-1, 4-endoxylanase (designated as AfXynA) that appeared in a single protein band on SDS-PAGE with a molecular mass of 20.2 kDa, which is different from all other reported xylanases from the same strain. The AfXynA exhibited a specific activity of 838.2 U/mg. Its optimal temperature and pH were determined to be 55 °C and 7.5, respectively. It was stable up to 50 °C and within pH 3.5-10.5. AfXynA also exhibited an excellent tolerance to various proteases. This new xylanase had an endohydrolytic mode of action and could hydrolyze xylotriose to xylobiose through transglycosylation. It could efficiently degrade xylan to mainly yield xylobiose, xylotriose, xylopentose and xylohexaose. In addition, the AfXynA was effective in hydrolyzing pretreated corncobs, and shows a great potential in the production of xylooligosaccharides. These unique enzymatic properties make the AfXynA attractive for more biotechnological applications.

An outbreak of epidemic keratoconjunctivitis caused by human adenovirus type 8 in primary school, southwest China.

BACKGROUND: Two outbreaks of epidemic keratoconjunctivitis (EKC) occurred successively with an interval of 5 days in two primary boarding schools in Weixi Lisu Autonomous County, Diqing, and Tibetan Autonomous Prefecture, Yunnan. The aims of this study were to determine the intensity and characteristics of the outbreaks, as well as the clinical manifestations in the patients, the risk factors for infection and the pathogen responsible for the two outbreaks. METHODS: An outbreak investigation was conducted in two primary schools, and a case-control study including patients from the Weixi County Ethnic Primary School was performed. Relevant specimens were collected according to the case definition, and next-generation sequencing was employed to identify the pathogen. An epidemiological investigation method was used to analyse the related epidemiological characteristics, such as risk factors. The phylogenetic tree was constructed by MEGA 7.0. RESULTS: A total of 331 acute conjunctivitis cases, including probable cases of EKC, were reported in the two schools, and the attack rates were 30.59% (171/559, 95%CI: 26.76-34.42) and 20.41% (160/784, 95%CI: 17.58-23.24), respectively. Cases occurred in all grades and classes in both schools, and only one staff member in each school presented illness. The epidemics lasted for 54 days and 45 days, respectively. The patients had typical manifestations of EKC, such as acute onset, follicular hyperplasia, pseudomembrane formation, preauricular lymphadenopathy, corneal involvement and blurred vision, and a relatively long disease course (average 9.40 days, longest 23 days and shortest 7 days). The risk factor for infection was close contact with a patient or personal items contaminated by a patient. The pathogen responsible for the outbreaks was HAdV-8. The virus was highly similar to the 2016 HAdV-8 strain from Tibet, China. CONCLUSIONS: This study strongly suggests that HAdV-8 could lead to serious consequences. This is the second report of a HAdV-8-associated EKC outbreak in mainland China. Tibetan HAdV-8 might be circulating in southwest China; therefore, it is necessary to monitor the pathogens causing acute conjunctivitis in this area.

Characterization of a novel xylanase from Aspergillus flavus with the unique properties in production of xylooligosaccharides.

A novel xylanase from the filamentous fungus Aspergillus flavus was purified and characterized as the ß-1, 4-endoxylanase (designed as AfXynB) with a molecular mass (32.2 kDa), which is different from all of the previously reported xylanases from the same strain. AfXynB was optimally active at pH 7.5 and 55 °C, respectively. It was stable up to 50 °C within range of pH 4.0-9.5, and displayed an excellent tolerance to various cations, reagents, and proteases. AfXynB showed specific activity toward beechwood xylan but no detected activity toward CMC and pNP-ß-D-xylopyranoside. The xylanase is a typical endo-xylanase; it could hydrolyze beechwood xylan to only yield xylobiose (X2) and xylopentaose (X5). Actually, this may be the first report for the endo-xylanases that displayed such a unique hydrolytic property. These findings in the present study have great implications for its future applications of the novel xylanase.

Purification and characterization of a novel ß-glucosidase from Aspergillus flavus and its application in saccharification of soybean meal.

Aspergillus flavus has been regarded as a potential candidate for its production of industrial enzymes, but the details of ß-glucosidase from this strain is very limited. In herein, we first reported a novel ß-glucosidase (AfBglA) with the molecular mass of 94.2 kDa from A. flavus. AfBglA was optimally active at pH 4.5 and 60 °C and is stable between pH 3.5 and 9.0 and at a temperature of up to 55 °C for 30 min remaining more than 90% of its initial activity. It showed an excellent tolerance to Trypsin, Pepsin, Compound Protease, and Flavourzyme and its activity was not inhibited by specific certain cations. AfBglA displayed broad substrate specificity, it acted on all tested pNP-glycosides and barley glucan, indicating this novel ß-glucosidase exhibited a ß-1, 3-1, 4-glucanase activity. Moreover, the AfBglA could effectively hydrolyze the soybean meal suspension into glucose and exhibit a strong tolerance to the inhibition of glucose at a concentration of 20.0 g/L during the saccharification. The maximum amount of the glucose obtained by AfBglA corresponded to 67.0 g/kg soybean meal. All of these properties mentioned above indicated that the AfBglA possibly attractive for food and feed industry and saccharification of cellulolytic materials.