A new Cinygmula McDunnough, 1933 species with distinct imaginal frontal fold from eastern Chinese Himalaya (Ephemeroptera: Heptageniidae).

In the family Heptageniidae (Ephemeroptera), Cinygmula hutchinsoni (Traver, 1939) from central Asia is the only species known to possess pointed claws and a distinct frontal fold. Here, a second similar species with the same combination of characters is described. Cinygmula longissima sp. nov. is found in the eastern Himalaya of China, shows stouter imaginal penes, darker wingbases, and narrower nymphal gills than the previous one. This discovery indicates that this species of Heptageniidae are not limited to central Asia but live in high-altitude alpine habitats.

JAM3: A prognostic biomarker for bladder cancer via epithelial­mesenchymal transition regulation

Understanding the intricate relationship between prognosis, immune function, and molecular markers in bladder cancer (BC) demands sophisticated analytical methods. To identify novel biomarkers for predicting prognosis and immune function in BC patients, we combined weighted gene co-expression network analysis (WGCNA) and least absolute shrinkage and selection operator (LASSO) regression analysis. This was conducted using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. Ultimately, we screened the junctional adhesion molecule 3 (JAM3) as an independent risk factor in BC. High levels of JAM3 were linked to adverse clinical parameters, such as higher T and N stages. Additionally, a JAM3-based nomogram model accurately predicted 1-, 3- and 5-year survival rates of BC patients, indicating potential clinical utility. Functional enrichment analysis revealed that high JAM3 expression activated the calcium signaling pathway, the extracellular matrix (ECM)-receptor interaction, and the PI3K-Akt signaling pathway, and was positively correlated with genes associated with epithelial­mesenchymal transition (EMT). Subsequently, we found that overexpression of JAM3 promoted the migration and invasion abilities in BC cells, regulating the expression levels of N-Cadherin, matrix metallopeptidase 2 (MMP2), and Claudin-1 thereby promoting EMT levels. Additionally, we showed that JAM3 was negatively correlated with anti-tumor immune cells such as CD8+T cells, while positively correlated with pro-tumor immune cells such as M2 macrophages, suggesting its involvement in immune cell infiltration. The immune checkpoint CD200 also showed a positive correlation with JAM3. Our findings revealed that elevated JAM3 levels are predictive of poor prognosis and immune cell infiltration in BC patients by regulating the EMT process.

Elementary Reactions in the Functional Triads of the Blue-Light Photoreceptor BLUF Domain.

The blue light using the flavin (BLUF) domain is one of the smallest photoreceptors in nature, which consists of a unique bidirectional electron-coupled proton relay process in its photoactivation reaction cycle. This perspective summarizes our recent efforts in dissecting the photocycle into three elementary processes, including proton-coupled electron transfer (PCET), proton rocking, and proton relay. Using ultrafast spectroscopy, we have determined the temporal sequence, rates, kinetic isotope effects (KIEs), and concertedness of these elementary steps. Our findings provide important implications for illuminating the photoactivation mechanism of the BLUF domain and suggest an engineering platform to characterize intricate reactions involving proton motions that are ubiquitous in nonphotosensitive protein machines.

Origin of the multi-phasic quenching dynamics in the BLUF domains across the species.

Blue light using flavin (BLUF) photoreceptors respond to light via one of nature's smallest photo-switching domains. Upon photo-activation, the flavin cofactor in the BLUF domain exhibits multi-phasic dynamics, quenched by a proton-coupled electron transfer reaction involving the conserved Tyr and Gln. The dynamic behavior varies drastically across different species, the origin of which remains controversial. Here, we incorporate site-specific fluorinated Trp into three BLUF proteins, i.e., AppA, OaPAC and SyPixD, and characterize the percentages for the Wout, WinNHin and WinNHout conformations using 19F nuclear magnetic resonance spectroscopy. Using femtosecond spectroscopy, we identify that one key WinNHin conformation can introduce a branching one-step proton transfer in AppA and a two-step proton transfer in OaPAC and SyPixD. Correlating the flavin quenching dynamics with the active-site structural heterogeneity, we conclude that the quenching rate is determined by the percentage of WinNHin, which encodes a Tyr-Gln configuration that is not conducive to proton transfer.

Single-Electron Oxidation-Initiated Enantioselective Hydrosulfonylation of Olefins Enabled by Photoenzymatic Catalysis.

Controlling the enantioselectivity of hydrogen atom transfer (HAT) reactions has been a long-standing synthetic challenge. While recent advances on photoenzymatic catalysis have demonstrated the great potential of non-natural photoenzymes, all of the transformations are initiated by single-electron reduction of the substrate, with only one notable exception. Herein, we report an oxidation-initiated photoenzymatic enantioselective hydrosulfonylation of olefins using a novel mutant of gluconobacter ene-reductase (GluER-W100F-W342F). Compared to known photoenzymatic systems, our approach does not rely on the formation of an electron donor-acceptor complex between the substrates and enzyme cofactor and simplifies the reaction system by obviating the addition of a cofactor regeneration mixture. More importantly, the GluER variant exhibits high reactivity and enantioselectivity and a broad substrate scope. Mechanistic studies support the proposed oxidation-initiated mechanism and reveal that a tyrosine-mediated HAT process is involved.

A new immune-related gene signature predicts the prognosis and immune escape of bladder cancer.

BACKGROUND: The biological roles of immune-related genes (IRGs) in bladder cancer (BC) need to be further elucidated. OBJECTIVE: To elucidate the predictive value of IRGs for prognosis and immune escape in BC. METHODS: We comprehensively analyzed the transcriptomic and clinical information of 430 cases, including 19 normal and 411 BC patients from the TCGA database, and verified 165 BC cases in the GSE13507 dataset. The risk model was constructed based on IRGs by applying LASSO Cox regression and exploring the relationship between the risk score and prognosis, gene mutations, and immune escape in BC patients. RESULTS: We identified 4 survival-related genes (PSMC1, RAC3, ROBO2 and ITGB3) among 6,196 IRGs in both the TCGA and GES13507 datasets,, which were used to establish a gene risk model by applying LASSO Cox regression. The results showed that the high-risk (HR) group was closely associated with poor survival or advanced pathological stage of BC. Furthermore, the risk score was found to be an independent risk factor for prognosis of BC patients. In addition, high-risk individuals showed a greater prevalence of TP53 mutations lower CD8+ T-cell and NK cell infiltration, higher Treg cell infiltration, higher expression of PD-L1, and higher immune exclusion scores than those in the low-risk (LR) group. Finally, the experimental verification shows that the model construction gene, especially PMSC1, plays an important role in the growth and metastasis of bladder cancer. CONCLUSIONS: These evidences revealed the vital role of IRGs in predicting prognosis, TP53 mutation and immune escape in BC patients.

Comprehensive analysis of integrin αvß3/α6ß1 in prognosis and immune escape of prostate cancer.

Integrin αvß3/α6ß1 are crucial in the transduction of intercellular cancer information, while their roles in prostate cancer (PCa) remain poorly understood. Here, we systematically analyzed the transcriptome, single nucleotide polymorphisms (SNPs) and clinical data of 495 PCa patients from the TCGA database and verified them in 220 GEO patients, and qPCR was used to validate the expression of the model genes in our patients. First, we found that integrin αvß3/α6ß1 was negatively correlated with most immune cell infiltration and immune functions and closely associated with poor survival in TCGA patients. Then, we divided these patients into two groups according to the expression level of αvß3/α6ß1, intersected differentially expressed genes of the two groups with the GEO dataset and identified eight biochemical recurrence-related genes (BRGs), and these genes were verified by qPCR in our patients. Next, these BRGs were used to construct a prognostic risk model by applying LASSO Cox regression. We found that the high-risk (HR) group showed poorer OS, PFS, biochemical recurrence and clinical characteristics than the low-risk (LR) group. In addition, the HR group was mainly enriched in the cell cycle pathway and had a higher TP53 mutation rate than the LR group. More importantly, lower immune cell infiltration and immune function, higher expression of PD-L1, PD-1, and CTLA4, and higher immune exclusion scores were identified in the HR group, suggesting a higher possibility of immune escape. These findings suggested the key role of integrin αvß3/α6ß1 in predicting prognosis, TP53 mutation and immune escape in PCa.

Coherent magnetic and electronic structure symmetry broken in frustrated bilayer Kagome ferromagnet Fe3Sn2.

In this letter, by measuring resistivity and magnetization with magnetic fieldHrotated inabplane and currentIalongcaxis, we studied the magnetic and electronic structure symmetry of frustrated topological bilayer Kagome ferromagnet Fe3Sn2. We observed that the curves of the resistivity and magnetization both showed broken two-fold symmetry from 5 K to 380 K. The further analysis indicates that there is a close causality between the spin arrangement and the electronic states in Fe3Sn2even above room temperature. These phenomena are closely related to the change in spin-orbit coupling (SOC) under the magnetic field. Our experimental results suggest that Fe3Sn2is an ideal platform to study the influence of spin arrangement on electronic state in topological materials and can also be used to design next generation magnetic devices by modulating SOC at external magnetic field.

An ultrafast phototrigger of the Trp5CN-Trp motif in a ß-hairpin peptide.

Phototriggers are useful molecular tools to initiate reactions in enzymes by light for the purpose of photoenzymatic design and mechanistic investigations. Here, we incorporated the non-natural amino acid 5-cyanotryptophan (W5CN) in a polypeptide scaffold and resolved the photochemical reaction of the W5CN-W motif using femtosecond transient UV/Vis and mid-IR spectroscopy. We identified a marker band of ∼2037 cm-1 from the CN stretch of the electron transfer intermediate W5CN·- in the transient IR measurement and found UV/Vis spectroscopic evidence for the W·+ radical at 580 nm. Through kinetic analysis, we characterized that the charge separation between the excited W5CN and W occurs in 253 ps, with a charge-recombination lifetime of 862 ps. Our study highlights the potential use of the W5CN-W pair as an ultrafast phototrigger to initiate reactions in enzymes that are not light-sensitive, making downstream reactions accessible to femtosecond spectroscopic detection.

Dissecting the Ultrafast Stepwise Bidirectional Proton Relay in a Blue-Light Photoreceptor.

Proton relays through H-bond networks are essential in realizing the functionality of protein machines such as in photosynthesis and photoreceptors. It has been challenging to dissect the rates and energetics of individual proton-transfer steps during the proton relay. Here, we have designed a proton rocking blue light using a flavin (BLUF) domain with the flavin mononucleotide (FMN)-glutamic acid (E)-tryptophan (W) triad and have resolved the four individual proton-transfer steps kinetically using ultrafast spectroscopy. We have found that after the photo-induced charge separation forming FMN·-/E-COOH/WH·+, the proton first rapidly jumps from the bridging E-COOH to FMN- (τfPT2 = 3.8 ps; KIE = 1.0), followed by a second proton transfer from WH·+ to E-COO- (τfPT1 = 336 ps; KIE = 2.6) which immediately rocks back to W· (τrPT1 = 85 ps; KIE = 6.7), followed by a proton return from FMNH· to E-COO- (τrPT2 = 34 ps; KIE = 3.3) with the final charge recombination between FMN·- and WH·+ to close the reaction cycle. Our results revisited the Grotthuss mechanism on the ultrafast timescale using the BLUF domain as a paradigm protein.

Survey on Energy Harvesting for Biomedical Devices: Applications, Challenges and Future Prospects for African Countries.

Self-powered biomedical devices, which are the new vision of Internet Of Things (IOT) healthcare, are facing many technical and application challenges. Many research works have reported biomedical devices and self-powered applications for healthcare, along with various strategies to improve the monitoring time of self-powered devices or to eliminate the dependence on electrochemical batteries. However, none of these works have especially assessed the development and application of healthcare devices in an African context. This article provides a comprehensive review of self-powered devices in the biomedical research field, introduces their applications for healthcare, evaluates their status in Africa by providing a thorough review of existing biomedical device initiatives and available financial and scientific cooperation institutions in Africa for the biomedical research field, and highlights general challenges for implementing self-powered biomedical devices and particular challenges related to developing countries. The future perspectives of the aforementioned research field are provided, as well as an architecture for improving this research field in developing countries.

Chirality flips of skyrmion bubbles.

The investigation of three-dimensional magnetic textures and chirality switching has attracted enormous interest from the perspective of fundamental research. Here, the three-dimensional magnetic structures of skyrmion bubbles in the centrosymmetric magnet MnNiGa were reconstructed with the vector field tomography approach via Lorentz transmission electron microscopy. The magnetic configuration of the bubbles was determined based on the reconstructed magnetic induction (B-field) at their surfaces and centers. We found that the bubbles easily switched their chirality but preserved their polarity to retain their singularity in the matrix of the material. Our results offer valuable insights into the chirality behavior of skyrmion bubbles.

Prognostic role of iodine values for gastric cancer after neoadjuvant chemotherapy: a strong independent prognostic factor.

PURPOSE We aimed to systematically explore the value of iodine values calculated from dual-energy computed tomography (DECT) as potential prognostic factors for locally advanced gastric cancer (LAGC) patients undergoing neoadjuvant chemotherapy (NAC). METHODS Eighty-five LAGC patients were examined using DECT before and after NAC and were divided into responders and non-responders based on the tumor regression grade (TRG). The iodine values, including portal- and delayed-phase iodine uptake (IU-p and IU-d, mg/ml) and total iodine uptake (TIU-p and TIU-d, mg) were acquired. Correlations between the reduction ratios of iodine values and TRG were analyzed. The diagnostic performance of parameters for differentiating responders from non-responders was calculated. Kaplan-Meier method was used for survival analysis. RESULTS The reduction ratios of total iodine uptake (%△TIU-p and %△TIU-d) were significantly correlated with TRG (p < 0.001). The ypN stage, %△TIU-p and %△TIU-d were significant factors influencing PFS (p < 0.050). A value of %△TIU-d≤62.19% was associated with negative prognosis [relative risk (RR):2.103; P = 0.021], as was ypN stage (RR:4.250; p = 0.003). CONCLUSION Iodine values (especially the TIU) are noninvasive quantitative parameters that are potentially helpful for evaluating the treatment response and survival prognosis of LAGC after NAC. %△TIU-d represents a strong independent prognostic factor, increasing preoperative risk assessment performance.

Magnetic Skyrmionic Bubbles at Room Temperature and Sign Reversal of the Topological Hall Effect in a Layered Ferromagnet Cr0.87Te.

The search for materials that exhibit topologically protected spin configurations, such as magnetic skyrmions, continues to be fueled by the promise of outstanding candidate components for spin-based applications. In this study, in situ Lorentz transmission electron microscopy directly images Bloch-type magnetic skyrmionic bubbles in a layered ferromagnet Cr0.87Te single crystal. Owing to the competition between a magnetic dipole interaction and uniaxial easy axis anisotropy, nanoscale magnetic bubbles with random chirality can be observed in a wide temperature range covering room temperature when the external magnetic field is applied along the out-of-plane direction. Moreover, high-density and stable skyrmionic bubbles are successfully realized at zero magnetic field by appropriate field-cooling manipulation. Additionally, a sign reversal of the Hall effect and the derived topological Hall effect is observed and discussed. As quasi-two-dimensional materials, the binary chromium tellurides hosting magnetic skyrmions could have many applications in low-dimensional skyrmion-based spintronic devices in an ambient atmosphere.

The nature of proton-coupled electron transfer in a blue light using flavin domain.

Proton-coupled electron transfer (PCET) is key to the activation of the blue light using flavin (BLUF) domain photoreceptors. Here, to elucidate the photocycle of the central FMN-Gln-Tyr motif in the BLUF domain of OaPAC, we eliminated the intrinsic interfering W90 in the mutant design. We integrated the stretched exponential function into the target analysis to account for the dynamic heterogeneity arising from the active-site solvation relaxation and the flexible H-bonding network as shown in the molecular dynamics simulation results, facilitating a simplified expression of the kinetics model. We find that, in both the functional wild-type (WT) and the nonfunctional Q48E and Q48A, forward PCET happens in the range of 105 ps to 344 ps, with a kinetic isotope effect (KIE) measured to be ∼1.8 to 2.4, suggesting that the nature of the forward PCET is concerted. Remarkably, only WT proceeds with an ultrafast reverse PCET process (31 ps, KIE = 4.0), characterized by an inverted kinetics of the intermediate FMNH˙. Our results reveal that the reverse PCET is driven by proton transfer via an intervening imidic Gln.

Quinoline-Based Photolabile Protection Strategy Facilitates Efficient Protein Assembly.

Native chemical ligation (NCL) provides a powerful solution to assemble proteins with precise chemical features, which enables a detailed investigation of the protein structure-function relationship. As an extension to NCL, the discovery of desulfurization and expressed protein ligation (EPL) techniques has greatly expanded the efficient access to large or challenging protein sequences via chemical ligations. Despite its superior reliability, the NCL-desulfurization protocol requires orthogonal protection strategies to allow selective desulfurization in the presence of native Cys, which is crucial to its synthetic application. In contrast to traditional thiol protecting groups, photolabile protecting groups (PPGs), which are removed upon irradiation, simplify protein assembly and therefore provide minimal perturbation to the peptide scaffold. However, current PPG strategies are mainly limited to nitro-benzyl derivatives, which are incompatible with NCL-desulfurization. Herein, we present for the first time that quinoline-based PPG for cysteine can facilitate various ligation strategies, including iterative NCL and EPL-desulfurization methods. 7-(Piperazin-1-yl)-2-(methyl)quinolinyl (PPZQ) caging of multiple cysteine residues within the protein sequence can be readily introduced via late-stage modification, while the traceless removal of PPZQ is highly efficient via photolysis in an aqueous buffer. In addition, the PPZQ group is compatible with radical desulfurization. The efficiency of this strategy has been highlighted by the synthesis of γ-synuclein and phosphorylated cystatin-S via one-pot iterative ligation and EPL-desulfurization methods. Besides, successful sextuple protection and deprotection of the expressed Interleukin-34 fragment demonstrate the great potential of this strategy in protein caging/uncaging investigations.

Direct Observation of Ultrafast Proton Rocking in the BLUF Domain.

We present direct observation of ultrafast proton rocking in the central motif of a BLUF domain protein scaffold. The mutant design has taken consideration of modulating the proton-coupled electron transfer (PCET) driving forces by replacing Tyr in the original motif with Trp, in order to remove the interference of a competing electron transfer pathway. Using femtosecond pump-probe spectroscopy and detailed kinetics analysis, we resolved an electron-transfer-coupled Grotthuss-type forward and reverse proton rocking along the FMN-Gln-Trp proton relay chain. The rates of forward and reverse proton transfer are determined to be very close, namely 51 ps vs. 52 ps. The kinetic isotope effect (KIE) constants associated with the forward and reverse proton transfer are 3.9 and 5.3, respectively. The observation of ultrafast proton rocking is not only a crucial step towards revealing the nature of proton relay in the BLUF domain, but also provides a new paradigm of proton transfer in proteins for theoretical investigations.

Ultrafast nonequilibrium dynamics of short-range protein electron transfer in flavodoxin.

Short-range protein electron transfer (ET) is ubiquitous in biology and is often observed in photosynthesis, photoreceptors and photoenzymes. These ET processes occur on an ultrafast timescale from femtoseconds to picoseconds at a short donor-acceptor distance within 10 Å, and thus couple with local environmental fluctuations. Here, we use oxidized Anabaena flavodoxin as a model system and have systematically studied the photoinduced redox cycle of the wild type and seven mutant proteins by femtosecond spectroscopy. We observed a series of ultrafast dynamics from the initial charge separation in 100-200 fs, subsequent charge recombination in 1-2 ps and final vibrational cooling process of the products in 3-6 ps. We further characterized the active-site solvation and observed the relaxations in 1-200 ps, indicating a nonergodic ET dynamics. With our new ET model, we uncovered a minor outer (solvent) reorganization energy and a large inner (donor and acceptor) reorganization energy, suggesting a frozen active site in the initial ultrafast ET while the back ET couples with the environment relaxations. The vibronically coupled back ET dynamics was first reported in D. vulgaris flavodoxin and here is observed in Anabaena flavodoxin again, completely due to the faster ET dynamics than the cooling relaxations. We also compared the two flavodoxin structures, revealing a stronger coupling with the donor tyrosine in Anabaena. All ultrafast ET dynamics are from the large donor-acceptor couplings and the minor activation barriers due to the reaction free energies being close to the inner reorganization energies. These observations should be general to many redox reactions in flavoproteins.