The scale of zebrafish pectoral fin buds is determined by intercellular K+ levels and consequent Ca2+-mediated signaling via retinoic acid regulation of Rcan2 and Kcnk5b.

K+ channels regulate morphogens to scale adult fins, but little is known about what regulates the channels and how they control morphogen expression. Using the zebrafish pectoral fin bud as a model for early vertebrate fin/limb development, we found that K+ channels also scale this anatomical structure, and we determined how one K+-leak channel, Kcnk5b, integrates into its developmental program. From FLIM measurements of a Förster Resonance Energy Transfer (FRET)-based K+ sensor, we observed coordinated decreases in intracellular K+ levels during bud growth, and overexpression of K+-leak channels in vivo coordinately increased bud proportions. Retinoic acid, which can enhance fin/limb bud growth, decreased K+ in bud tissues and up-regulated regulator of calcineurin (rcan2). rcan2 overexpression increased bud growth and decreased K+, while CRISPR-Cas9 targeting of rcan2 decreased growth and increased K+. We observed similar results in the adult caudal fins. Moreover, CRISPR targeting of Kcnk5b revealed that Rcan2-mediated growth was dependent on the Kcnk5b. We also found that Kcnk5b enhanced depolarization in fin bud cells via Na+ channels and that this enhanced depolarization was required for Kcnk5b-enhanced growth. Lastly, Kcnk5b-induced shha transcription and bud growth required IP3R-mediated Ca2+ release and CaMKK activity. Thus, we provide a mechanism for how retinoic acid via rcan2 can regulate K+-channel activity to scale a vertebrate appendage via intercellular Ca2+ signaling.

An unexpected hydratase synthesizes the green light-absorbing pigment fucoxanthin.

The ketocarotenoid fucoxanthin and its derivatives can absorb blue-green light enriched in marine environments. Fucoxanthin is widely adopted by phytoplankton species as a main light-harvesting pigment, in contrast to land plants that primarily employ chlorophylls. Despite its supreme abundance in the oceans, the last steps of fucoxanthin biosynthesis have remained elusive. Here, we identified the carotenoid isomerase-like protein CRTISO5 as the diatom fucoxanthin synthase that is related to the carotenoid cis-trans isomerase CRTISO from land plants but harbors unexpected enzymatic activity. A crtiso5 knockout mutant in the model diatom Phaeodactylum tricornutum completely lacked fucoxanthin and accumulated the acetylenic carotenoid phaneroxanthin. Recombinant CRTISO5 converted phaneroxanthin into fucoxanthin in vitro by hydrating its carbon-carbon triple bond, instead of functioning as an isomerase. Molecular docking and mutational analyses revealed residues essential for this activity. Furthermore, a photophysiological characterization of the crtiso5 mutant revealed a major structural and functional role of fucoxanthin in photosynthetic pigment-protein complexes of diatoms. As CRTISO5 hydrates an internal alkyne physiologically, the enzyme has unique potential for biocatalytic applications. The discovery of CRTISO5 illustrates how neofunctionalization leads to major diversification events in evolution of photosynthetic mechanisms and the prominent brown coloration of most marine photosynthetic eukaryotes.

Air pollutants, genetic susceptibility, and abdominal aortic aneurysm risk: a prospective study.

BACKGROUND AND AIMS: Air pollutants are important contributors to cardiovascular diseases, but associations between long-term exposure to air pollutants and the risk of abdominal aortic aneurysm (AAA) are still unknown. METHODS: This study was conducted using a sample of 449 463 participants from the UK Biobank. Hazard ratios and 95% confidence intervals for the risk of AAA incidence associated with long-term exposure to air pollutants were estimated using the Cox proportional hazards model with time-varying exposure measurements. Additionally, the cumulative incidence of AAA was calculated by using the Fine and Grey sub-distribution hazards regression model. Furthermore, this study investigated the combined effects and interactions between air pollutants exposure and genetic predisposition in relation to the risk of AAA onset. RESULTS: Long-term exposure to particulate matter with an aerodynamic diameter <2.5 µm [PM2.5, 1.21 (1.16, 1.27)], particulate matter with an aerodynamic diameter <10 µm [PM10, 1.21 (1.16, 1.27)], nitrogen dioxide [NO2, 1.16 (1.11, 1.22)], and nitrogen oxides [NOx, 1.10 (1.05, 1.15)] was found to be associated with an elevated risk of AAA onset. The detrimental effects of air pollutants persisted even in participants with low-level exposure. For the joint associations, participants with both high levels of air pollutants exposure and high genetic risk had a higher risk of developing AAA compared with those with low concentrations of pollutants exposure and low genetic risk. The respective risk estimates for AAA incidence were 3.18 (2.46, 4.12) for PM2.5, 3.09 (2.39, 4.00) for PM10, 2.41 (1.86, 3.13) for NO2, and 2.01 (1.55, 2.61) for NOx. CONCLUSIONS: In this study, long-term air pollutants exposure was associated with an increased risk of AAA incidence.

Customizable Click Biochemistry Strategy for the Design and Preparation of Glucagon-like Peptide-1 Conjugates and Coagonists.

The development of oligomeric glucagon-like peptide-1 (GLP-1) and GLP-1-containing coagonists holds promise for enhancing the therapeutic potential of the GLP-1-based drugs for treating type 2 diabetes mellitus (T2DM). Here, we report a facile, efficient, and customizable strategy based on genetically encoded SpyCatcher-SpyTag chemistry and an inducible, cleavable self-aggregating tag (icSAT) scheme. icSAT-tagged SpyTag-fused GLP-1 and the dimeric or trimeric SpyCatcher scaffold were designed for dimeric or trimeric GLP-1, while icSAT-tagged SpyCatcher-fused GLP-1 and the icSAT-tagged SpyTag-fused GIP were designed for dual GLP-1/GIP (glucose-dependent insulinotropic polypeptide) receptor agonist. These SpyCatcher- and SpyTag-fused protein pairs were spontaneously ligated directly from the cell lysates. The subsequent icSAT scheme, coupled with a two-step standard column purification, resulted in target proteins with authentic N-termini, with yields ranging from 35 to 65 mg/L and purities exceeding 99%. In vitro assays revealed 3.0- to 4.1-fold increased activities for dimeric and trimeric GLP-1 compared to mono-GLP-1. The dual GLP-1/GIP receptor agonist exhibited balanced activity toward the GLP-1 receptor or the GIP receptor. All the proteins exhibited 1.8- to 3.0-fold prolonged half-lives in human serum compared to mono-GLP-1 or GIP. This study provides a generally applicable click biochemistry strategy for developing oligomeric or dual peptide/protein-based drug candidates.

Experimental Quantum Non-Gaussian Coincidences of Entangled Photons.

Quantum non-Gaussianity, a more potent and highly useful form of nonclassicality, excludes all convex mixtures of Gaussian states and Gaussian parametric processes generating them. Here, for the first time, we conclusively test quantum non-Gaussian coincidences of entangled photon pairs with the Clauser-Horne-Shimony-Holt-Bell factor S=2.328±0.004 from a single quantum dot with a depth up to 0.94±0.02 dB. Such deterministically generated photon pairs fundamentally overcome parametric processes by reducing crucial multiphoton errors. For the quantum non-Gaussian depth of the unheralded (heralded) single-photon state, we achieve the value of 8.08±0.05 dB (19.06±0.29 dB). Our Letter experimentally certifies the exclusive quantum non-Gaussianity properties highly relevant for optical sensing, communication, and computation.

Experimental Generation of Spin-Photon Entanglement in Silicon Carbide.

A solid-state approach for quantum networks is advantageous, as it allows the integration of nanophotonics to enhance the photon emission and the utilization of weakly coupled nuclear spins for long-lived storage. Silicon carbide, specifically point defects within it, shows great promise in this regard due to the easy of availability and well-established nanofabrication techniques. Despite of remarkable progresses made, achieving spin-photon entanglement remains a crucial aspect to be realized. In this Letter, we experimentally generate entanglement between a silicon vacancy defect in silicon carbide and a scattered single photon in the zero-phonon line. The spin state is measured by detecting photons scattered in the phonon sideband. The photonic qubit is encoded in the time-bin degree of freedom and measured using an unbalanced Mach-Zehnder interferometer. Photonic correlations not only reveal the quality of the entanglement but also verify the deterministic nature of the entanglement creation process. By harnessing two pairs of such spin-photon entanglement, it becomes straightforward to entangle remote quantum nodes at long distance.

Targeting ATP-binding site of WRN Helicase: Identification of novel inhibitors through pocket analysis and Molecular Dynamics-Enhanced virtual screening.

WRN helicase is a critical protein involved in maintaining genomic stability, utilizing ATP hydrolysis to dissolve DNA secondary structures. It has been identified as a promising synthetic lethal target for microsatellite instable (MSI) cancers. However, few WRN helicase inhibitors have been discovered, and their potential binding sites remain unexplored. In this study, we analyzed potential binding sites for WRN inhibitors and focused on the ATP-binding site for screening new inhibitors. Through molecular dynamics-enhanced virtual screening, we identified two compounds, h6 and h15, which effectively inhibited WRN's helicase and ATPase activity in vitro. Importantly, these compounds selectively targeted WRN's ATPase activity, setting them apart from other non-homologous proteins with ATPase activity. In comparison to the homologous protein BLM, h6 exhibits some degree of selectivity towards WRN. We also investigated the binding mode of these compounds to WRN's ATP-binding sites. These findings offer a promising strategy for discovering new WRN inhibitors and present two novel scaffolds, which might be potential for the development of MSI cancer treatment.

Discovery of novel selective phosphodiesterase­1 inhibitors for the treatment of acute myelogenous leukemia.

Acute myelogenous leukemia (AML) is the most common form of acute leukemia in adults. PDE1 (Phosphodiesterase 1) is a subfamily of the PDE super-enzyme families that can hydrolyze the second messengers cAMP and cGMP simultaneously. Previous research has shown that suppressing the gene expression of PDE1 can trigger apoptosis of human leukemia cells. However, no selective PDE1 inhibitors have been used to explore whether PDE1 is a potential target for treating AML. Based on our previously reported PDE9/PDE1 dual inhibitor 11a, a series of novel pyrazolopyrimidinone derivatives were designed in this study. The lead compound 6c showed an IC50 of 7.5 nM against PDE1, excellent selectivity over other PDEs and good metabolic stability. In AML cells, compound 6c significantly inhibited the proliferation and induced apoptosis. Further experiments indicated that the apoptosis induced by 6c was through a mitochondria-dependent pathway by decreasing the ratio of Bcl-2/Bax and increasing the cleavage of caspase-3, 7, 9, and PARP. All these results suggested that PDE1 might be a novel target for AML.

The dual function of cGAS-STING signaling axis in liver diseases.

Numerous liver diseases, such as nonalcoholic fatty liver disease, hepatitis, hepatocellular carcinoma, and hepatic ischemia-reperfusion injury, have been increasingly prevalent, posing significant threats to global health. In recent decades, there has been increasing evidence linking the dysregulation of cyclic-GMP-AMP synthase (cGAS)-stimulator of interferon gene (STING)-related immune signaling to liver disorders. Both hyperactivation and deletion of STING can disrupt the immune microenvironment dysfunction, exacerbating liver disorders. Consequently, there has been a surge in research investigating medical agents or mediators targeting cGAS-STING signaling. Interestingly, therapeutic manipulation of the cGAS-STING pathway has yielded inconsistent and even contradictory effects on different liver diseases due to the distinct physiological characteristics of intrahepatic cells that express and respond to STING. In this review, we comprehensively summarize recent advancements in understanding the dual roles of the STING pathway, highlighting that the benefits of targeting STING signaling depend on the specific types of target cells and stages of liver injury. Additionally, we offer a novel perspective on the suitability of STING agonists and antagonists for clinical assessment. In conclusion, STING signaling remains a highly promising therapeutic target, and the development of STING pathway modulators holds great potential for the treatment of liver diseases.

Baicalein attenuates rotenone-induced SH-SY5Y cell apoptosis through binding to SUR1 and activating ATP-sensitive potassium channels.

Dopaminergic neurons in the substantia nigra (SN) expressing SUR1/Kir6.2 type ATP-sensitive potassium channels (K-ATP) are more vulnerable to rotenone or metabolic stress, which may be an important reason for the selective degeneration of neurons in Parkinson's disease (PD). Baicalein has shown neuroprotective effects in PD animal models. In this study, we investigated the effect of baicalein on K-ATP channels and the underlying mechanisms in rotenone-induced apoptosis of SH-SY5Y cells. K-ATP currents were recorded from SH-SY5Y cells using whole-cell voltage-clamp recording. Drugs dissolved in the external solution at the final concentration were directly pipetted onto the cells. We showed that rotenone and baicalein opened K-ATP channels and increased the current amplitudes with EC50 values of 0.438 µM and 6.159 µM, respectively. K-ATP channel blockers glibenclamide (50 µM) or 5-hydroxydecanoate (5-HD, 250 µM) attenuated the protective effects of baicalein in reducing reactive oxygen species (ROS) content and increasing mitochondrial membrane potential and ATP levels in rotenone-injured SH-SY5Y cells, suggesting that baicalein protected against the apoptosis of SH-SY5Y cells by regulating the effect of rotenone on opening K-ATP channels. Administration of baicalein (150, 300 mg·kg-1·d-1, i.g.) significantly inhibited rotenone-induced overexpression of SUR1 in SN and striatum of rats. We conducted surface plasmon resonance assay and molecular docking, and found that baicalein had a higher affinity with SUR1 protein (KD = 10.39 µM) than glibenclamide (KD = 24.32 µM), thus reducing the sensitivity of K-ATP channels to rotenone. Knockdown of SUR1 subunit reduced rotenone-induced apoptosis and damage of SH-SY5Y cells, confirming that SUR1 was an important target for slowing dopaminergic neuronal degeneration in PD. Taken together, we demonstrate for the first time that baicalein attenuates rotenone-induced SH-SY5Y cell apoptosis through binding to SUR1 and activating K-ATP channels.

Residential greenness and incident idiopathic pulmonary fibrosis: A prospective study.

BACKGROUND: The impact of residential greenness on incident idiopathic pulmonary fibrosis (IPF) is unknown. We aimed to assess the association between residential greenness and incident IPF, identify underlying pathways, and further evaluate the effect among different genetic subgroups. METHODS: 469,348 participants in the UK Biobank were included and followed until December 2020. Normalized difference vegetation index (NDVI) within 300-, 500-, 1000-, and 1500-m buffers (NDVI300m, NDVI500m, NDVI1000m, and NDVI1500m) were employed as indicators of greenness. The polygenic risk score (PRS) was constructed based on 13 independent SNPs. Cox models were fitted to assess the association of residential greenness with incident IPF. Casual mediation analyses were applied to evaluate potential mediators. FINDINGS: After a median follow-up of 11.85 years, 1574 IPF cases were identified. We found residential greenness inversely associated with incident IPF. The HRs (95%CIs) for each interquartile increase of NDVI300m, NDVI500m, NDVI1000m, NDVI1500m were 0.93 (0.87, 0.99), 0.92 (0.86, 0.98), 0.89 (0.83, 0.95), and 0.89 (0.83, 0.95), respectively. The association was stronger among individuals with intermediate or high genetic risk. In mediation analyses, the main mediators identified were PM2.5 and NO2, with proportion mediated estimated to be 31.92% and 40.61% respectively for NDVI300m. INTERPRETATION: Residential greenness was associated with reduced risk of incident IPF.

Breaking down barriers: rationalisations and motivation to stop among Chinese male smokers under cigarette dependence.

BACKGROUND: Smoking rationalisation beliefs are a huge barrier to quitting smoking. What types of rationalisations should be emphasised in smoking cessation interventions? Although past literature has confirmed the negative relationship between those beliefs and motivation to stop smoking, little is known regarding the importance and performance of those beliefs on motivation with varying cigarette dependence. The study aimed to ascertain rationalisations that are highly important for motivation yet perform poorly in different cigarette dependence groups. METHODS: The cross-sectional study was conducted from November 19 to December 9, 2023 in Guiyang City, China. Adult male current smokers were enrolled. Partial least squares structural equation modelling was used to test the hypothesis. The multi-group analysis was used to determine the moderating effect of cigarette dependence, and the importance-performance map analysis was utilised to assess the importance and performance of rationalisations. RESULTS: A total of 616 adult male current smokers were analysed, and they were divided into the low cigarette dependence group (n = 297) and the high cigarette dependence group (n = 319). Except for risk generalisation beliefs, smoking functional beliefs (H1: -ß = 0.131, P < 0.01), social acceptability beliefs (H3: ß = -0.258, P < 0.001), safe smoking beliefs (H4: ß = -0.078, P < 0.05), self-exempting beliefs (H5: ß = -0.244, P < 0.001), and quitting is harmful beliefs (H6: ß = -0.148, P < 0.01) all had a significant positive influence on motivation. Cigarette dependence moderated the correlation between rationalisations and motivation. In the high-dependence group, the social acceptability beliefs and smoking functional beliefs were located in the "Concentrate Here" area. In the low-dependence group, the social acceptability beliefs were also situated in there. CONCLUSIONS: Social acceptability beliefs and smoking functional beliefs showed great potential and value for improvement among high-dependence smokers, while only social acceptability beliefs had great potential and value for improvement among low-dependence smokers. Addressing these beliefs will be helpful for smoking cessation. The multi-group analysis and the importance-performance map analysis technique have practical implications and can be expanded to other domains of health education and intervention practice.

Catastrophic cascade of failures in interdependent hypergraphs.

The failures of individual agents can significantly impact the functionality of associated groups in interconnected systems. To reveal these impacts, we develop a threshold model to investigate cascading failures in double-layer hypergraphs with interlayer interdependence. We hypothesize that a hyperedge disintegrates when the proportion of failed nodes within it exceeds a threshold. Due to the interdependence between a node and its replica in the other layer, the disintegrations of these hyperedges could trigger a cascade of events, leading to an iterative collapse across these two layers. We find that double-layer hypergraphs undergo abrupt, discontinuous first-order phase transitions during systemic collapse regardless of the specific threshold value. Additionally, the connectivity measured by average cardinality and hyperdegree plays a crucial role in shaping system robustness. A higher average hyperdegree always strengthens system robustness. However, the relationship between system robustness and average cardinality exhibits non-monotonic behaviors. Specifically, both excessively small and large average cardinalities undermine system robustness. Furthermore, a higher threshold value can boost the system's robustness. In summary, our study provides valuable insights into cascading failure dynamics in double-layer hypergraphs and has practical implications for enhancing the robustness of complex interdependent systems across domains.

microRNA-3037 targeting CYP6CY2 confers imidacloprid resistance to Sitobion miscanthi (Takahashi).

The wheat aphid Sitobion miscanthi is a dominant and destructive pest in agricultural production. Insecticides are the main substances used for effective control of wheat aphids. However, their extensive application has caused severe resistance of wheat aphids to some insecticides; therefore, exploring resistance mechanisms is essential for wheat aphid management. In the present study, CYP6CY2, a new P450 gene, was isolated and overexpressed in the imidacloprid-resistant strain (SM-R) compared to the imidacloprid-susceptible strain (SM-S). The increased sensitivity of S. miscanthi to imidacloprid after knockdown of CYP6CY2 indicates that it could be associated with imidacloprid resistance. Subsequently, the posttranscriptional regulation of CYP6CY2 in the 3' UTR by miR-3037 was confirmed, and CYP6CY2 participated in imidacloprid resistance. This finding is critical for determining the role of P450 in relation to the resistance of S. miscanthi to imidacloprid. It is of great significance to understand this regulatory mechanism of P450 expression in the resistance of S. miscanthi to neonicotinoids.

Potential mechanisms of hexaconazole resistance in Fusarium graminearum.

The Fusarium head blight (FHB) caused by Fusarium graminearum is a serious fungal disease that can dramatically impact wheat production. At present, control is mainly achieved by the use of chemical fungicides. Hexaconazole (IUPAC name: 2-(2,4-dichlorophenyl)-1-(1,2,4-triazol-1-yl)hexan-2-ol) is a widely used triazole fungicide, but the sensitivity of F. graminearum to this compound has yet to be established. The current study found that the EC50 values of 83 field isolates of F. graminearum ranged between 0.06 and 4.33 µg/mL, with an average EC50 of 0.78 µg/mL. Assessment of four hexaconazole-resistant laboratory mutants of F. graminearum revealed that their mycelial growth, and pathogenicity were reduced compared to their parental isolates, and that asexual reproduction was reduced by resistance to hexaconazole. Meanwhile, the mutants appeared to be more sensitive to abiotic stress associated with SDS, and H2O2, while their tolerance of high concentration of Congo red, and Na+ and K+ increased. Molecular analysis revealed numerous point mutations in the FgCYP51 target genes that resulted in amino acid substitutions, including L92P and N123S in FgCYP51A, as well as M331V, F62L, Q252R, A412V, and V488A in FgCYP51B, and S28L, S256A, V307A, D287G and R515I in FgCYP51C, three of which (S28L, S256A, and V307A) were conserved in all of the resistant mutants. Furthermore, the expression of the FgCYP51 genes in resistant strains was found to be significantly (p < 0.05) reduced compared to their sensitive parental isolates. Positive cross-resistance was found between hexaconazole and metconazole and flutriafol, as well as with the diarylamine fungicide fluazinam, but not with propiconazole, and the phenylpyrrole fungicide fludioxonil, or with tebuconazole, which actually exhibited negative cross-resistance. These results provide valuable insight into resistant mechanisms to triazole fungicides in F. graminearum, as well as the appropriate selection of fungicide combinations for the control of FHB to ensure optimal wheat production.

Biosynthetic pathway analysis combined with feature-based molecular networking to comprehensively characterize the chemical constituents in seeds of Sterculia lychnophora.

INTRODUCTION: The seeds of Sterculia lychnophora Hance, commonly known as Pangdahai (PDH) in Chinese, have found extensive use in both culinary and traditional medicinal practices. However, a comprehensive understanding of the chemical composition of PDH has been lacking. OBJECTIVES: This study proposes a strategy that integrates biosynthetic pathway analysis with feature-based molecular networking (FBMN), aiming for a thorough and global characterization of the chemical compositions of PDH. METHODOLOGY: The FBMN map reveals potential compounds with structural similarity, and the MS/MS fragments could be annotated based on library matches, which could predict the plausible biosynthetic pathways in PDH, accomplishing the annotation of compounds clustered in FBMN by integrating biosynthetic pathways. RESULTS: Consequently, 126 compounds were plausibly or unambiguously identified, including 37 phenolic acids and glycosides, 20 flavonoids and glycosides, 12 procyanidins, 21 alkaloids, 22 lipids, and 14 others. Leveraging the information, 40 compounds, including 1 unique isoquinoline alkaloid and 2 rare linear furocoumarins, were isolated and confirmed. CONCLUSIONS: This study not only demonstrates a highly effective approach for identifying compounds within complex herbal mixtures but also establishes a robust foundation for the further development of PDH.

Quality markers of Dajianzhong decoction based on multicomponent qualitative and quantitative analysis combined with network pharmacology and chemometric analysis.

INTRODUCTION: Dajianzhong decoction (DJZD), a classic famous prescription, has a long history of medicinal application. Modern studies have demonstrated its clinical utility in the treatment of postoperative ileus (POI). But none of the current quality evaluation methods for this compound is associated with efficacy. OBJECTIVES: This study aimed to identify the quality markers (Q-Markers) connected to the treatment of POI in DJZD. METHODOLOGY: Ultra-performance liquid chromatography quadrupole Exactive Orbitrap mass spectrometry (UPLC-Q-Exactive Orbitrap-MS) was used to identify the main constituents in DJZD. Based on the qualitative results obtained by fingerprinting, chemical pattern recognition (CPR) was used to analyse the key components affecting the quality and finally to establish the network of the active ingredients in DJZD with POI. RESULTS: A total of 64 chemical components were detected. After fingerprint analysis, 13 common peaks were identified. The fingerprint similarity of 15 batches of samples ranged from 0.860 to 1.000. CPR analysis was able to categorically classify 15 batches of DJZD into two groups. And gingerenone A, methyl-6-gingerdiol, 6-gingerol, and hydroxy-ß-sanshool contributed to their grouping. Twelve common components interact with the therapeutic targets for treating POI. In addition, the mechanism of this prescription for treating POI may be related to the jurisdiction of the neurological system, the immunological system, and the inflammatory response. CONCLUSIONS: This integrated approach can accurately assess and forecast the quality of DJZD, presume the Q-Markers of DJZD for POI, and lay the foundation for studying the theoretical underpinnings and exploring the mechanism of DJZD in the treatment of POI.

Comparative proteomic analysis of seminal plasma exosomes in buffalo with high and low sperm motility.

BACKGROUND: Exosomes are nanosized membranous vesicles secreted by various types of cells, which facilitate intercellular communication by transporting bioactive compounds. Exosomes are abundant in biological fluids including semen, and their protein composition and the potential of seminal plasma exosomes (SPEs) as fertility biomarkers were elucidated in humans, however, little information is available regarding buffalo (Bubalus bubalis). Here, we examined protein correlation between spermatozoa, seminal plasma (SP), and SPEs, and we compared and analyzed protein differences between high-motility (H-motility) and low-motility (L-motility) SPEs in buffalo. RESULTS: SPEs were concentrated and purified by ultracentrifugation combined with sucrose density gradient centrifugation, followed by verification using western blotting, nanoparticle tracking analysis, and transmission electron microscopy. Protein composition in spermatozoa, SP and SPEs, and protein difference in H- and L-motility SPEs were identified by LC-MS/MS proteomic analysis and were functionally analyzed through comprehensive bioinformatics. Many SPEs proteins originated from spermatozoa and SP, and nearly one third were also present in spermatozoa and SP. A series of proteins associated with reproductive processes including sperm capacitation, spermatid differentiation, fertilization, sperm-egg recognition, membrane fusion, and acrosome reaction were integrated in a functional network. Comparative proteomic analyses showed 119 down-regulated and 41 up-regulated proteins in L-motility SPEs, compared with H-motility SPEs. Gene Ontology (GO) enrichment of differentially expressed proteins (DEPs) showed that most differential proteins were located in sperm and vesicles, with activities of hydrolase and metalloproteinase, and were involved in sperm-egg recognition, fertilization, single fertilization, and sperm-zona pellucida binding processes, etc. Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that differential proteins were mainly involved in the PPRP signaling pathway, calcium signaling pathway, and cAMP signaling pathway, among others. Furthermore, 6 proteins associated with reproduction were validated by parallel reaction monitoring analysis. CONCLUSION: This study provides a comprehensive description of the seminal plasma exosome proteome and may be of use for further screening of biomarkers associated with male infertility.

Reflective one-to-multi-polarization conversion via separate control of phase and magnitude.

Polarization manipulation is a key issue in electromagnetic (EM) research. Research on 90° polarization rotators and circularly-polarized wave generators has been widely conducted. In this study, a polarization conversion metasurface that can shift one linearly-polarized EM wave into multi-polarization outgoing waves at certain frequencies is demonstrated, including co-, cross-, left-hand, and right-hand circular-polarization components. The surface was made of periodically arranged chiral meta-atoms. The polarization manipulation method is based on the independent control of phase and magnitude, in which the phase control is based on the Berry-phase theory of linearly-polarized EM waves, while the magnitude control is based on the cavity mode theory of the microstrip structure. Both eigenmode analysis (EMA) and characteristic mode analysis (CMA) were utilized for magnitude control, which was further verified by the surface current distribution. Finally, the metasurface was fabricated and measured, showing good agreement between the measured and simulated results. This research proposed what we believe to be a novel polarization method, which can be potentially applied in polarization manipulation, EM radiation, filters, wireless sensors, etc., over a frequency range from optics to microwave bands.

Comprehensive measurement of the near-infrared refractive index of GaAs at cryogenic temperatures.

The refractive index is a critical parameter in optical and photonic device design. However, due to the lack of available data, precise designs of devices working in low temperatures are still frequently limited. In this work, we have built a homemade spectroscopic ellipsometer (SE) and measured the refractive index of GaAs at a matrix of temperatures (4 K < T < 295 K) and photon wavelengths (700 nm < λ < 1000 nm) with a system error of ∼0.04. We verified the credibility of the SE results by comparing them with afore-reported data at room temperature and with higher precision values measured by vertical GaAs cavity at cryogenic temperatures. This work makes up for the lack of the near-infrared refractive index of GaAs at cryogenic temperatures and provides accurate reference data for semiconductor device design and fabrication.