ELONGATED HYPOTCOTYL5 and SPINE BASE SIZE1 together mediate light-regulated spine expansion in cucumber.

Plant trichome development is influenced by diverse developmental and environmental signals, but the molecular mechanisms involved are not well understood in most plant species. Fruit spines (trichomes) are an important trait in cucumber (Cucumis sativus L.), as they affect both fruit smoothness and commercial quality. Spine Base Size1 (CsSBS1) has been identified as essential for regulating fruit spine size in cucumber. Here, we discovered that CsSBS1 controls a season-dependent phenotype of spine base size in wild-type plants. Decreased light intensity led to reduced expression of CsSBS1 and smaller spine base size in wild-type plants, but not in the mutants with CsSBS1 deletion. Additionally, knockout of CsSBS1 resulted in smaller fruit spine base size and eliminated the light-induced expansion of spines. Overexpression of CsSBS1 increased spine base size and rescued the decrease in spine base size under low light conditions. Further analysis revealed that ELONGATED HYPOTCOTYL5 (HY5), a major transcription factor involved in light signaling pathways, directly binds to the promoter of CsSBS1 and activates its expression. Knockout of CsHY5 led to smaller fruit spine base size and abolished the light-induced expansion of spines. Taken together, our study findings have clarified a CsHY5-CsSBS1 regulatory module that mediates light-regulated spine expansion in cucumber. This finding offers a strategy for cucumber breeders to develop fruit with stable appearance quality under changing light conditions.

Long noncoding RNA ANRIL alleviates hypoxia-induced pulmonary microvascular endothelial cell damage.

BACKGROUND: High-altitude pulmonary oedema (HAPE) is a form of noncardiogenic pulmonary oedema. Studies have found that long noncoding RNA (lncRNA) plays an important role in HAPE. ANRIL is significant in pulmonary illnesses, which implies that alterations in ANRIL expression levels may be involved in the beginning and development of HAPE. However, the specific mechanism is indistinct. The present study is meant to explore the effect and mechanism of ANRIL on hypoxic-induced injury of pulmonary microvascular endothelial cells (PMEVCs). METHODS: In the hypoxic model of PMVECs, overexpression of ANRIL or knockdown of miR-181c-5p was performed to assess cell proliferation, apoptosis, and migration. Furthermore, the levels of apoptosis-related proteins, inflammatory factors, and vascular active factors were also measured. RESULTS: The results showed that, after 24 h of hypoxia, PMVECs proliferation and migration were suppressed in comparison to the control group, along with an increase in apoptosis, a decrease in the expression of ANRIL, and an increase in the expression of miR-181c-5p (all p < .05). The damage caused by hypoxia in PMVECs can be lessened by overexpressing ANRIL, which also inhibits the production of TNF-α, iNOS, and VEGF as well as BAX and cleaved caspase-3 (all p < .05). Further experimental results showed that overexpression of ANRIL and knockdown of miR-181c-5p had the same protection against hypoxic injury in PMVECs (all p < .05). CONCLUSIONS: Our study suggests that ANRIL may prevent hypoxia injury to PMVECs in HAPE through the negative regulation of miR-181c-5p.

Evaluation and systematic review of guidance documents for status epilepticus.

Guidance documents play a pivotal role in shaping the management of status epilepticus (SE). However, the methodological quality of these documents remains uncertain. In this systematic review, we comprehensively searched 12 literature and guideline databases to assess the quality of clinical practice guidelines and consensus statements related to SE management using the AGREE II methodology. Additionally, we summarized the associated recommendations. We identified a total of 14 clinical practice guidelines and 11 consensus statements spanning the period from 1993 to 2022. The median score for clarity of presentation was 71.8% (ranging from 15.3% to 91.7%), indicating generally good clarity. However, the aspect of editorial independence received poor ratings, with a median score of 32.1% (ranging from 0% to 83.3%). Notably, the 2016 guideline published by the American Epilepsy Society in Epilepsy (AES) received the highest overall scores. Across these guidance documents, there was consistency in the definition and diagnosis of SE. However, significant variability was observed in therapeutic recommendations, particularly in terms of the timing for adding or changing medications. The methodological approaches used in most SE guidance documents require improvement, and the disparities in recommendations highlight existing gaps in evidence. Enhanced methodological rigor results in increased standardization of the guideline, consequently augmenting its reference value. Given the urgency of SE as an emergency condition, it is imperative that these documents also address relevant management strategies before admission.

Predictive Value of CFIm25 Expression in Peripheral Blood Monocytes for Coronary Atherosclerosis.

Background: Cleavage factor Im25 (CFIm25) regulates cell function by affecting mRNA editing processes and plays diverse roles in various diseases. Studies have found that peripheral blood monocytes are valuable in diagnosing and prognosing coronary atherosclerosis. However, no studies have examined the predictive value of CFIm25 expression in peripheral blood monocytes for coronary atherosclerosis. Methods and Results: We collected the coronary angiography results of 267 patients and calculated the Gensini score to evaluate their degree of coronary atherosclerosis. We isolated peripheral blood monocytes and detected CFIm25 RNA expression. Based on their Gensini score, we divided the patients into negative (0, n = 46), mild lesion (≤ 8, n = 71), moderate lesion (8-23, n = 76), and severe lesion (≥ 23, n = 74) groups. Results showed that CFIm25 expression correlated negatively with the Gensini score and the number of involved coronary vessels. Univariate and multivariate binary logistic regression analyses showed that CFIm25 expression in peripheral blood monocytes was a protective factor for severe lesions, ≥ 50% stenosis, and three-vessel lesions. The areas under the receiver operating characteristic curve of CFIm25 expression for predicting lesions, severe lesions, ≥50% stenosis, and three-vessel lesions were 0.743, 0.735, 0.791, and 0.736, respectively. Conclusions: CFIm25 expression in peripheral blood monocytes correlates negatively with the degree of coronary atherosclerosis and helps predict the severity and number of coronary artery lesions.

Chlorothalonil exposure compromised mouse oocyte in vitro maturation through inducing oxidative stress and activating MAPK pathway.

Chlorothalonil (CTL) is widely used in agricultural production and antifoulant additive globally due to its broad spectrum and non-systemic properties, resulting in its widespread existence in foods, soil and water. Extensive evidence demonstrated that exposure to CTL induced adverse effects on organisms and in particular its reproductive toxicity has been attracted public concern. However, the influences of CTL on oocyte maturation is mysterious so far. In this study, we documented the toxic effects of CTL on oocyte in vitro maturation and the related underlying mechanisms. Exposure to CTL caused continuous activation of spindle assembly checkpoints (SAC) which in turn compromised meiotic maturation in mouse oocyte, featured by the attenuation of polar body extrusion (PBE). Detection of cytoskeletal dynamics demonstrated that CTL exposure weakened the acetylation level of α-tubulin and impaired meiotic spindle apparatus, which was responsible for the aberrant state of SAC. Meanwhile, exposure to CTL damaged the function of mitochondria, inducing the decline of ATP content and the elevation of reactive oxygen species (ROS), which thereby induced early apoptosis and DNA damage in mouse oocytes. In addition, exposure to CTL caused the alteration of the level of histone H3 methylation, indicative of the harmful effects of CTL on epigenetic modifications in oocytes. Further, the CTL-induced oxidative stress activated mitogen-activated protein kinase (MAPK) pathway and injured the maturation of oocytes. In summary, exposure to CTL damaged mouse oocyte in vitro maturation via destroying spindle assembly, inducing oxidative stress and triggering MAPK pathway activation.

Na2S2O3 Catalyzed Three-Component Synthesis and Anti-Bacterial Activity of 3-Methyl-4-(hetero)arylmethylene isoxazole-5(4H)-ones.

An efficient and green method for synthesizing 3-methyl-4-(hetero) arylmethylene isoxazole-5(4H)-ones was developed using a recyclable and environmental-friendly catalyst, Na2S2O3, and 16 target compounds were successfully synthesized under the obtained optimal reaction condition. Using rifampicin as a positive control, the antibacterial activity of all synthesized compounds was tested by micro dilution method, among them, 3-methyl-4-[(2,4-dimethoxyphenyl) methylene]-isoxazole-5-one (4 m) presented wonderful antimicrobial activity, which may contribute to the development of anti-tuberculosis drugs.

"UHPLC-Q-TOF/MS-chemometrics-network pharmacology" integrated strategy to discover quality markers of raw and stir-fried Fructus Tribuli and process optimization of stir-fried Fructus Tribuli.

INTRODUCTION: Fructus Tribuli, the dried ripe fruit of Tribulus terrestris L., has various beneficial effects, including liver-calming and depression-relieving effects. Raw Fructus Tribuli (RFT) and stir-fried Fructus Tribuli (SFT) are included in the Chinese Pharmacopoeia 2020 edition (Ch. P 2020). However, owing to the lack of specific regulations on SFT-processing parameters in Ch. P 2020, it is difficult to ensure the quality of commercially available SFT. OBJECTIVE: The present study aimed to screen the quality markers (Q-markers) of RFT and SFT and optimize the processing technology of SFT based on the identified Q-markers. METHODS: First, the ultra-high-performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UHPLC-Q-TOF/MS) technology as well as multiple statistical analysis along with network pharmacology was used to comprehensively identify the Q-markers of RFT and SFT. Then, based on single-factor experiments, the Box-Behnken design (BBD) response surface methodology (RSM) was used to optimize the processing technology of SFT and perform process validation. RESULTS: A total of 63 components were identified in RFT and SFT extracts. Terrestrosin D and Terrestrosin K were initially considered the Q-markers of RFT and SFT, respectively. The optimum processing technology conditions were 208°C, 14 min, and 60 r·min-1. Three batches of process validation were performed, and the mean composite score was 56.87, with a relative standard deviation (RSD) value of 1.13%. CONCLUSION: The content of steroidal saponin components in RFT was significantly different before and after stir-frying. Terrestrosin D and Terrestrosin K were validated as the Q-markers of RFT and SFT, respectively. The identification of Q-markers for RFT and SFT offered a clear index for optimizing the SFT-processing technology and provided a basis for the quality control of RFT and SFT decoction pieces.

Hypothetical protein MAA_07646 is required for stress resistance and pathogenicity in Metarhizium robertsii.

Metarhizium robertsii, a vital entomopathogenic fungus for pest management, relies on various virulence-related proteins for infection. Identifying these proteins, especially those with unknown functions, can illuminate the fungus's virulence mechanisms. Through RNA-seq, we discovered that the hypothetical protein MAA_07646 was significantly upregulated during appressorium formation in M. robertsii. In this study, we characterized MAA_07646, finding its presence in both the nucleus and cytoplasm. Surprisingly, it did not affect vegetative growth, conidiation, or chemical tolerance. However, it played a role in heat and UV radiation sensitivity. Notably, ΔMAA_07646 exhibited reduced virulence in Galleria mellonella larvae due to impaired appressorium formation and decreased expression of virulence-related genes. In conclusion, MAA_07646 contributes to thermotolerance, UV resistance, and virulence in M. robertsii. Understanding its function sheds light on the insecticidal potential of M. robertsii's hypothetical proteins.

External Fields Assisted Highly Efficient Oxygen Evolution Reaction of Confined 1T-VSe2 Ferromagnetic Nanoparticles.

As a clean and effective approach, the introduction of external magnetic fields to improve the performance of catalysts has attracted extensive attention. Owing to its room-temperature ferromagnetism, chemical stability, and earth abundance, VSe2 is expected to be a promising and cost-effective ferromagnetic electrocatalyst for the accomplishment of high-efficient spin-related OER kinetics. In this work, a facile pulsed laser deposition (PLD) method combined with rapid thermal annealing (RTA) treatment is used to successfully confine monodispersed 1T-VSe2 nanoparticles in amorphous carbon matrix. As expected, with external magnetic fields of 800 mT stimulation, the confined 1T-VSe2 nanoparticles exhibit highly efficient oxygen evolution reaction (OER) catalytic activity with an overpotential of 228 mV for 10 mA cm-2 and remarkable durability without deactivation after >100 h OER operation. The experimental results together with theoretical calculations illustrate that magnetic fields can facilitate the surface charge transfer dynamics of 1T-VSe2 , and modify the adsorption-free energy of *OOH, thus finally improving the intrinsic activity of the catalysts. This work realizes the application of ferromagnetic VSe2 electrocatalyst in highly efficient spin-dependent OER kinetics, which is expected to promote the application of transition metal chalcogenides (TMCs) in external magnetic field-assisted electrocatalysis.

Zebrafish cox17 modulates primitive erythropoiesis via regulation of mitochondrial metabolism to facilitate hypoxia tolerance.

Cox17 is required in the assembly of mitochondrial intermembrane space (IMS) and Cu metallization of cytochrome C oxidase (CcO) in mitochondria as well as Cu homeostasis in cells. Cox deficiency is associated with hematopoietic diseases such as tubulopathy and leukodystrophy, but whether and how cox17 functions in hematopoiesis are still unknown. Here, we report the effects of zebrafish cox17 deficiency on primitive erythropoiesis, mitochondrial metabolism, and hypoxia tolerance. Cox17-/- larvae were sensitive to hypoxia stress, with reduced primitive erythropoiesis. Meanwhile, cox17-/- mutants showed a significant reduction in the expression of pivotal transcriptional regulators in erythropoiesis, such as scl, lmo2, and gata1a at 14 h post fertilization (hpf), with expression remaining downregulated for scl but upregulated for lmo2 and gata1a at 24 hpf. Mechanistically, cox17-/- mutants showed impaired mitochondrial metabolism, coupled with a significant decrease in the mitochondrial membrane potential, ATP and SAM content, and the ratio of SAM and SAH. Additionally, disrupting mitochondrial metabolism in wild type (WT) larvae treated with carbonyl cyanide 3-chlorophenylhydrazone (CCCP) could mimic the primitive erythropoiesis defects observed in cox17-/- mutants. Moreover, cox17-/- mutants exhibited significantly downregulated WNT signaling and upregulated ER stress, with a significant reduction of beta-Catenin in gata1a+ cells and of binding enrichment in both scl and lmo2 promoters of the WNT transcriptional factor TCF4. This is the first report on the novel linkage of cox17 deficiency with defective primitive erythropoiesis and reduced hypoxia tolerance. This study has shed light on the potential mechanism by which Cox deficiency, especially cox17 deficiency, induces Cu homeostasis imbalance, leading to hematopoietic diseases.

Zero-Dimensional Halides with ns2 Electron (Sb3+) Activation to Generate Broad Photoluminescence.

Organic-inorganic metal halides (OIMHs) have various crystal structures and offer excellent semiconducting properties. Here, we report three novel OIMHs, (PPA)6InBr9 (PPA = [C6H5(CH2)3NH3]+), (PBA)2SbBr5, and (PBA)2SbI6 (PBA = [C6H5(CH2)4NH3]+), showing typical zero-dimensional (0D) structure, octahedra dimers, and corner-sharing one-dimensional chains and crystallized in the monoclinic system with P21, P21/c, and C2/c space groups, respectively. (PPA)6InBr9, (PBA)2SbBr5, and (PBA)2SbI6 have experimental optical band gaps of ∼3.16, ∼2.24, and 1.48 eV, respectively. (PPA)6InBr9 exhibits bright-orange light emission centered at 642 nm with a full-width at half-maximum of 179 nm (0.51 eV) and a Stokes shift of 277 nm (1.46 eV). After Sb3+ doping, the peak position did not change, and the photoluminescence quantum yield increased significantly from 9.2 to 53.0%. The efficient emission of Sb:(PPA)6InBr9 stems from the isolated ns2 luminescent center and strong electron-phonon coupling, making the spin-forbidden 3P1-1S0 observable. By combining commercial blue and green phosphors with orange-red-light-emitting (PPA)6In0.99Sb0.01Br9, a white-light-emitting diode was constructed, with the color-rendering index reaching up to 92.3. Our work highlights three novel 0D OIMHs, with chemical doping of Sb3+ shown to significantly enhance the luminescence properties, demonstrating their potential applications in solid-state lighting.

Transgenerational Effects and Mechanisms of Tributyltin Exposure on Neurodevelopment in the Male Offspring of Rats.

This study aimed to investigate the transgenerational effects of tributyltin exposure on rat neurodevelopment in male offspring and the potential mechanisms. Neonatal female rats were exposed to the environmental level of tributyltin and then mated with nonexposed males after sexual maturity to produce the F1 generation. The F1 generation (with primordial germ cell exposure) was mated with nonexposed males to produce nonexposed offspring (the F2 and F3 generations). Neurodevelopmental indicators and behavior were observed for the F1, F2, and F3 generations during postnatal days 1-25 and 35-56, respectively. We found premature eye-opening and delayed visual positioning in newborn F1 rats and anxiety and cognitive deficits in prepubertal F1 male rats. These neurodevelopmental impacts were also observed in F2 and F3 males. Additionally, F1-F3 males exhibited increased serotonin and dopamine levels and a loose arrangement of neurons in the hippocampus. We also observed a reduction in the expression of genes involved in intercellular adhesion and increased DNA methylation of the Dsc3 promoter in F1-F3 males. We concluded that tributyltin exposure led to transgenerational effects on neurodevelopment via epigenetic reprogramming in male offspring. These findings provide insights into the risks of neurodevelopmental disorders in offspring from parents exposed to tributyltin.

Metarhizium robertsii MrAbaA affects conidial pigmentation via regulating MrPks1 and MrMlac1 expression.

Pigments of conidia play a crucial role in fungal defense against environmental stressors such as UV radiation. The molecular basis of conidial pigmentation has been studied in the entomopathogenic fungus Metarhizium robertsii, while limited information been reported on function mechanisms transcription factors governing conidial pigmentation. Here, we identified transcription factor MrAbaA binding to the promoter regions of both MrPks1 and MrMlac1 in M. robertsii using yeast one-hybrid technology. Chromatin immunoprecipitation quantitative PCR assays further confirmed the interaction. Furthermore, overexpression of MrAbaA in M. robertsii resulted in increased conidial pigment accumulation and enhanced tolerances to UV stress by upregulated the MrPks1 and MrMlac1 expression. Taken together, MrAbaA affects conidial pigmentation by interacting with the promoter regions of both MrPks1 and MrMlac1 in M. robertsii. This work advances the understanding of the regulation mechanism for conidial pigmentation in entomopathogenic fungi.

Unexpected Discovery and Expression of Amphibian Class II Endogenous Retroviruses.

Endogenous retroviruses (ERVs) are the remnants of past retroviral infections. Fossil records of class II retroviruses have been discovered in a range of vertebrates, with the exception of amphibians, which are known only to possess class I and class III-like ERVs. Through genomic mining of all available amphibian genomes, we identified, for the first time, class II ERVs in amphibians. The class II ERVs were found only in Gymnophiona (caecilians) and not in the genomes of the other amphibian orders, Anura (frogs and toads) and Caudata (salamanders and newts), which are phylogenetically closely related. Therefore, the ERV endogenization occurred after the split of Gymnophiona, Anura, and Caudata (323 million years ago). Investigation of phylogenetic relationship and genomic structure revealed that the ERVs may originate from alpha- or betaretroviruses. We offer evidence that class II ERVs infiltrated amphibian genomes recently and may still have infectious members. Remarkably, certain amphibian class II ERVs can be expressed in diverse tissues. This discovery closes the major gap in the retroviral fossil record of class II ERVs and provides important insights into the evolution of class II ERVs in vertebrates.IMPORTANCE Class II retroviruses, largely distributed among mammals and birds, are of particular importance for medicine and economics. Class II ERVs have been discovered in a range of vertebrates, with the exception of amphibians, which are known only to possess class I and class III-like ERVs. Here, for the first time, we discovered class II ERVs in amphibians. We also revealed that the ERVs may originate from alpha- or betaretroviruses. We revealed that class II ERVs were integrated into amphibian genomes recently and certain amphibian class II ERVs can be expressed in diverse tissues. Our discovery closes the major gap in the retroviral fossil record of class II ERVs, and also indicates that amphibians may be still infected by class II retroviruses.

Reassortment with dominant chicken H9N2 influenza virus contributed to the fifth H7N9 virus human epidemic.

H9N2 Avian influenza virus (AIV) is regarded as a principal donor of viral genes through reassortment to co-circulating influenza viruses that can result in zoonotic reassortants. Whether H9N2 virus can maintain sustained evolutionary impact on such reassortants is unclear. Since 2013, avian H7N9 virus had caused five sequential human epidemics in China; the fifth wave in 2016-2017 was by far the largest but the mechanistic explanation behind the scale of infection is not clear. Here, we found that, just prior to the fifth H7N9 virus epidemic, H9N2 viruses had phylogenetically mutated into new sub-clades, changed antigenicity and increased its prevalence in chickens vaccinated with existing H9N2 vaccines. In turn, the new H9N2 virus sub-clades of PB2 and PA genes, housing mammalian adaptive mutations, were reassorted into co-circulating H7N9 virus to create a novel dominant H7N9 virus genotype that was responsible for the fifth H7N9 virus epidemic. H9N2-derived PB2 and PA genes in H7N9 virus conferred enhanced polymerase activity in human cells at 33°C and 37°C, and increased viral replication in the upper and lower respiratory tracts of infected mice which could account for the sharp increase in human cases of H7N9 virus infection in the 2016-2017 epidemic. The role of H9N2 virus in the continual mutation of H7N9 virus highlights the public health significance of H9N2 virus in the generation of variant reassortants of increasing zoonotic potential.IMPORTANCEAvian H9N2 influenza virus, although primarily restricted to chicken populations, is a major threat to human public health by acting as a donor of variant viral genes through reassortment to co-circulating influenza viruses. We established that the high prevalence of evolving H9N2 virus in vaccinated flocks played a key role, as donor of new sub-clade PB2 and PA genes in the generation of a dominant H7N9 virus genotype (G72) with enhanced infectivity in humans during the 2016-2017 N7N9 virus epidemic. Our findings emphasize that the ongoing evolution of prevalent H9N2 virus in chickens is an important source, via reassortment, of mammalian adaptive genes for other influenza virus subtypes. Thus, close monitoring of prevalence and variants of H9N2 virus in chicken flocks is necessary in the detection of zoonotic mutations.

Sacubitril/valsartan attenuates myocardial ischemia/reperfusion injury via inhibition of the GSK3ß/NF-κB pathway in cardiomyocytes.

In ischemia/reperfusion (I/R) injury, both inflammation and apoptosis play a vital role, and the inhibition of excessive inflammation and apoptosis show substantial clinical potential in the treatment of I/R disease. The role of sacubitril/valsartan (SAC/VAL)-a first-in-class angiotensin receptor-neprilysin inhibitor (ARNI)-in inflammation regulation and apoptosis in the context of I/R injury needs to be further explored. In this study, we investigate the short- and long-term effects of SAC/VAL administration in treating adult murine I/R injury both in vivo and in vitro. Our results verified that the application of SAC/VAL could reduce infarct size and suppress apoptosis and the inflammatory response in the acute phase post I/R. Long-term application of SAC/VAL for four weeks significantly improved ventricular function and reversed pathological ventricular remodeling. Mechanistically, SAC/VAL treatment induces the inhibition of the GSK3ß-mediated NF-κB pathway through synergistically blocking angiotensin 1 receptor (AT1R) and activating natriuretic peptide receptor (NPR). In summary, we reported the therapeutic role of SAC/VAL in regulating the GSK3ß/NF-κB signaling pathway to suppress the inflammatory response and apoptosis, thereby reducing cardiac dysfunction and remodeling post I/R.

Boosting the OER Performance of Nitrogen-Doped Ni Nanoclusters Confined in an Amorphous Carbon Matrix.

Nanoclusters are ideal electrocatalysts due to their high surface activity. However, their high activities also lead to serious agglomeration and performance attenuation during the catalytic process. Here, highly dispersed Ni nanoclusters (∼3 nm) confined in an amorphous carbon matrix are successfully fabricated by pulsed laser deposition, followed by rapid temperature annealing treatment. Then, the Ni nanoclusters are further doped with nitrogen element through a clean N2 radio frequency plasma technology. It is found that the nitrogen-doped Ni nanoclusters obtained under optimized conditions showed superior OER performance with a very low overpotential of 240 mV at a current density of 10 mA/cm2, together with good stability. The excellent OER performance of the nanoclusters can be attributed to the unique confined structure and nitrogen doping, which not only provide more active sites but also improve the conductivity. Our work provides a controllable method for the construction of a novel confined structure with controllable nitrogen doping, which can be used as a high-efficiency OER electrocatalyst.

An R195K Mutation in the PA-X Protein Increases the Virulence and Transmission of Influenza A Virus in Mammalian Hosts.

In the 21st century, the emergence of H7N9 and H1N1/2009 influenza viruses, originating from animals and causing severe human infections, has prompted investigations into the genetic alterations required for cross-species transmission. We previously found that replacement of the human-origin PA gene segment in avian influenza virus (AIV) could overcome barriers to cross-species transmission. Recently, it was reported that the PA gene segment encodes both the PA protein and a second protein, PA-X. Here, we investigated the role of PA-X. We found that an H9N2 avian influenza reassortant virus bearing a human-origin H1N1/2009 PA gene was attenuated in mice after the loss of PA-X. Reverse genetics analyses of PA-X substitutions conserved in human influenza viruses indicated that R195K, K206R, and P210L substitutions conferred significantly increased replication and pathogenicity on H9N2 virus in mice and ferrets. PA-X R195K was present in all human H7N9 and H1N1/2009 viruses and predominated in human H5N6 viruses. Compared with PA-X 195R, H7N9 influenza viruses bearing PA-X 195K showed increased replication and transmission in ferrets. We further showed that PA-X 195K enhanced lung inflammatory responses, potentially due to decreased host shutoff function. A competitive transmission study in ferrets indicated that 195K provides a replicative advantage over 195R in H1N1/2009 viruses. In contrast, PA-X 195K did not influence the virulence of H9N2 AIV in chickens, suggesting that the effects of the substitution were mammal specific. Therefore, future surveillance efforts should scrutinize this region of PA-X because of its potential impact on cross-species transmission of influenza viruses.IMPORTANCE Four influenza pandemics in humans (the Spanish flu of 1918 [H1N1], the Asian flu of 1957 [H2N2], the Hong Kong flu of 1968 [H3N2], and the swine origin flu of 2009 [H1N1]) are all proposed to have been caused by avian or swine influenza viruses that acquired virulence factors through adaptive mutation or reassortment with circulating human viruses. Currently, influenza viruses circulating in animals are repeatedly transmitted to humans, posing a significant threat to public health. However, the molecular properties accounting for interspecies transmission of influenza viruses remain unclear. In the present study, we demonstrated that PA-X plays an important role in cross-species transmission of influenza viruses. At least three human-specific amino acid substitutions in PA-X dramatically enhanced the adaptation of animal influenza viruses in mammals. In particular, PA-X 195K might have contributed to cross-species transmission of H7N9, H5N6, and H1N1/2009 viruses from animal reservoirs to humans.

MoS2 Nanoribbons with a Prolonged Photoresponse Lifetime for Enhanced Visible Light Photoelectrocatalytic Hydrogen Evolution.

The high recombination rate of photoinduced electron-hole pairs limits the hydrogen production efficiency of the MoS2 catalyst in photoelectrochemical (PEC) water splitting. The strategy of prolonging the lifetime of photoinduced carriers is of great significance to the promotion of photoelectrocatalytic hydrogen production. An ideal approach is to utilize edge defects, which can capture photoinduced electrons and thus slow down the recombination rate. However, for two-dimensional MoS2, most of the surface areas are inert basal planes. Here, a simple method for preparing one-dimensional MoS2 nanoribbons with abundant inherent edges is proposed. The MoS2 nanoribbon-based device has a good spectral response in the range of 400-500 nm and has a longer lifetime of photoinduced carriers than other MoS2 nanostructure-based photodetectors. An improved PEC catalytic performance of these MoS2 nanoribbons is also experimentally verified under the illumination of 405 nm by using the electrochemical microcell technique. This work provides a new strategy to prolong the lifetime of photoinduced carriers for further improvement of PEC activity, and the evaluation of photoelectric performance provides a feasible way for transition-metal dichalcogenides to be widely used in the energy field.

High stability of photovoltaic cells with phenethylammonium iodide-passivated perovskite layers and printable copper phthalocyanine-modified carbon electrodes.

Defects caused by the structural disorder of perovskites and voltage loss resulting from mismatched band structure are important issues to address to improve the performance of carbon-based perovskite solar cells. Different from the conventional approaches of additive-based passivation of perovskite precursors and introducing a hole-transport layer between the perovskite layer and carbon electrode, herein we report a defect-healing method using phenethyl ammonium iodide (PEAI) treatment and band-structure modification using high-work-function inorganic copper phthalocyanine (CuPc). Because of its relatively smoother surfaces and lower defect content, the optimized device after PEAI-based passivation of the perovskite achieves a power conversion efficiency (PCE) of 11.74%. The PCE is further raised to 13.41% through the auxiliary energy-level matching and high hole extraction abilities of the CuPc-modified carbon electrode. The best-performing device exhibits excellent moisture tolerance and thermal stability with minor current density-voltage hysteresis.