Comparing Sonazoid contrast-enhanced ultrasound to contrast-enhanced CT and MRI for differentially diagnosing renal lesions: a prospective multicenter study.

PURPOSE: To evaluate the diagnostic performance of contrast-enhanced (CE) ultrasound using Sonazoid (SNZ-CEUS) by comparing with contrast-enhanced computed tomography (CE-CT) and contrast-enhanced magnetic resonance imaging (CE-MRI) for differentiating benign and malignant renal masses. MATERIALS AND METHODS: 306 consecutive patients (from 7 centers) with renal masses (40 benign tumors, 266 malignant tumors) diagnosed by both SNZ-CEUS, CE-CT or CE-MRI were enrolled between September 2020 and February 2021. The examinations were performed within 7 days, but the sequence was not fixed. Histologic results were available for 301 of 306 (98.37%) lesions and 5 lesions were considered benign after at least 2 year follow-up without change in size and image characteristics. The diagnostic performances were evaluated by sensitivity, specificity, positive predictive value, negative predictive value, and compared by McNemar's test. RESULTS: In the head-to-head comparison, SNZ-CEUS and CE-MRI had comparable sensitivity (95.60 vs. 94.51%, P = 0.997), specificity (65.22 vs. 73.91%, P = 0.752), positive predictive value (91.58 vs. 93.48%) and negative predictive value (78.95 vs. 77.27%); SNZ-CEUS and CE-CT showed similar sensitivity (97.31 vs. 96.24%, P = 0.724); however, SNZ-CEUS had relatively lower than specificity than CE-CT (59.09 vs. 68.18%, P = 0.683). For nodules > 4 cm, CE-MRI demonstrated higher specificity than SNZ-CEUS (90.91 vs. 72.73%, P = 0.617) without compromise the sensitivity. CONCLUSIONS: SNZ-CEUS, CE-CT, and CE-MRI demonstrate desirable and comparable sensitivity for the differentiation of renal mass. However, the specificity of all three imaging modalities is not satisfactory. SNZ-CEUS may be a suitable alternative modality for patients with renal dysfunction and those allergic to gadolinium or iodine-based agents.

Analysis of deformation mechanism of rainfall-induced landslide in the Three Gorges Reservoir Area: Piansongshu landslide.

The Three Gorges Reservoir Area (TGRA) is characterized by unique geological features that increase its susceptibility to landslides. These slopes are especially prone to destabilization when influenced by external triggers like rainfall. This research focuses on the Piansongshu landslide within the TGRA, aiming at unraveling the complex internal deformation mechanisms of landslides triggered by rainfall and providing critical insights for their prevention and mitigation. The study begins with on-site geological surveys to meticulously examine the macroscopic signs and mechanisms of deformation. It then utilizes the GeoStudio numerical simulation software to assess the landslide's stability, focusing on the changes in internal seepage fields and stability under various rainfall scenarios. Results indicate that continuous rainfall leads to the formation of a temporary saturation zone on the slope, which gradually deepens. In regions with more pronounced deformation, the infiltration line at the leading edge of accumulation notably protrudes towards the surface. Notably, the stability coefficient of the secondary shear surface of the landslide fluctuates more significantly than that of the primary sliding surface. Higher rainfall intensity and longer duration are positively correlated with a more pronounced decrease in stability coefficients. The impact on stability also varies across different rainfall patterns. As rainfall infiltrates over time, the slope's safety factor gradually decreases. This reduction continues even post-rainfall, indicating a delayed restoration period before stability returns to a safe level. These results yield valuable data for forecasting and mitigating landslides.

Association between gut microbiota and central retinal artery occlusion: A two-sample Mendelian randomization study.

PURPOSE: The gut microbiota might be closely related to central retinal artery occlusion (CRAO), but the causality has not been well defined. Two-sample Mendelian randomization (MR) study was used to reveal the potential causal effect between the gut microbiota and CRAO. METHODS: Data for gut microbiota were obtained from the genome-wide association studies of the Dutch Microbiome Project (DMP) (n = 7738) and the MiBioGen consortium (n = 18,340), and data on CRAO were obtained from samples of FinnGen project (546 cases and 344,569 controls). Causalities of exposures and outcomes were explored mainly using the inverse variance weighted method. In addition, multiple sensitivity analyses including MR-Egger, weighted median (WM), simple mode, weighted mode, and MR Pleiotropy RESidual Sum and Outlier were simultaneously applied to validate the final results. RESULTS: We identified three microbial pathways (two risk factors/one protective factor) and seven microbial taxa (two risk factors/five protective factors) associated with CRAO in the DMP study. Based on the data from the MiBioGen consortium, we identified seven microbial taxa (two risk factors/five protective factors) associated with CRAO, including the Eubacterium genus, which was consistently identified as a risk factor in both the DMP and the MiBioGen consortium MR analyses. CONCLUSION: Our study implicates the potential causal effects of specific microbial taxa and pathways on CRAO, potentially providing new insights into the prevention and treatment of CRAO through specific gut microbial taxa and pathway. Since our conclusion is a hypothesis derived from secondary genome-wide association studies (GWAS) data analysis, further research is needed for confirmation.

Umpolung reactivity of strained C-C σ-bonds without transition-metal catalysis.

Umpolung is an old and important concept in organic chemistry, which significantly expands the chemical space and provides unique structures. While, previous research focused on carbonyls or imine derivatives, the umpolung reactivity of polarized C-C σ-bonds still needs to explore. Herein, we report an umpolung reaction of bicyclo[1.1.0]butanes (BCBs) with electron-deficient alkenes to construct the C(sp3)-C(sp3) bond at the electrophilic position of C-C σ-bonds in BCBs without any transition-metal catalysis. Specifically, this transformation relies on the strain-release driven bridging σ-bonds in bicyclo[1.1.0]butanes (BCBs), which are emerged as ene components, providing an efficient and straightforward synthesis route of various functionalized cyclobutenes and conjugated dienes, respectively. The synthetic utilities of this protocol are performed by several transformations. Preliminary mechanistic studies including density functional theory (DFT) calculation support the concerted Alder-ene type process of C-C σ-bond cleavage with hydrogen transfer. This work extends the umpolung reaction to C-C σ-bonds and provides high-value structural motifs.

C166 EVs potentiate miR cardiac reprogramming via miR-148a-3p.

We have demonstrated that directly reprogramming cardiac fibroblasts into new cardiomyocytes via miR combo improves cardiac function in the infarcted heart. However, major challenges exist with delivery and efficacy. During a screening based approach to improve delivery, we discovered that C166-derived EVs were effective delivery agents for miR combo both in vitro and in vivo. In the latter, EV mediated delivery of miR combo induced significant conversion of cardiac fibroblasts into cardiomyocytes (∼20%), reduced fibrosis and improved cardiac function in a myocardial infarction injury model. When compared to lipid-based transfection, C166 EV mediated delivery of miR combo enhanced reprogramming efficacy. Improved reprogramming efficacy was found to result from a miRNA within the exosome: miR-148a-3p. The target of miR-148a-3p was identified as Mdfic. Over-expression and targeted knockdown studies demonstrated that Mdfic was a repressor of cardiomyocyte specific gene expression. In conclusion, we have demonstrated that C166-derived EVs are an effective method for delivering reprogramming factors to cardiac fibroblasts and we have identified a novel miRNA contained within C166-derived EVs which enhances reprogramming efficacy.

Modifying miRs for effective reprogramming of fibroblasts to cardiomyocytes.

Reprogramming scar fibroblasts into cardiomyocytes has been proposed to reverse the damage associated with myocardial infarction. However, the limited improvement in cardiac function calls for enhanced strategies. We reported enhanced efficacy of our miR reprogramming cocktail miR combo (miR-1, miR-133a, miR-208a, and miR-499) via RNA-sensing receptor stimulation. We hypothesized that we could combine RNA-sensing receptor activation with fibroblast reprogramming by chemically modifying miR combo. To test the hypothesis, miR combo was modified to enhance interaction with the RNA-sensing receptor Rig1 via the addition of a 5'-triphosphate (5'ppp) group. Importantly, when compared with unmodified miR combo, 5'ppp-modified miR combo markedly improved reprogramming efficacy in vitro. Enhanced reprogramming efficacy correlated with a type-I interferon immune response with strong and selective secretion of interferon ß (IFNß). Antibody blocking studies and media replacement experiments indicated that 5'ppp-miR combo utilized IFNß to enhance fibroblast reprogramming efficacy. In conclusion, miRs can acquire powerful additional roles through chemical modification that potentially increases their clinical applications.

Retinoblastoma and polydactyly in a child with 46, XY, 15pstk+ karyotype-A case report and literature review.

BACKGROUND: Retinoblastoma (Rb) is the most common intraocular malignancy in childhood, originating from primitive retinal stem cells or cone precursor cells. It can be triggered by mutations of the RB1 gene or amplification of the MYCN gene. Rb may rarely present with polydactyly. METHODS: We conducted karyotype analysis, copy number variation sequencing, and whole-genome sequencing on the infant proband and his family. The clinical course and laboratory results of the proband's infant were documented and collected. We also reviewed the relevant literature. RESULTS: A 68-day-old boy presented with preaxial polydactyly and corneal edema. His intraocular pressure (IOP) was 40/19 mmHg, and color Doppler imaging revealed vitreous solid mass-occupying lesions with calcification in the right eye. Ocular CT showed flaky high-density and calcification in the right eye. This was classified as an International Retinoblastoma Staging System group E retinoblastoma with an indication for enucleation. Enucleation and orbital implantation were performed on the child's right eye. Karyotype analysis revealed an abnormal 46, XY, 15pstk+ karyotype, and the mother exhibited diploidy of the short arm of chromosome 15. The Alx-4 development factor, 13q deletion syndrome, and the PAPA2 gene have been reported as potential mechanisms for Rb combined with polydactyly. CONCLUSION: We report the case of a baby boy with Rb and polydactyly exhibiting a 46, XY, 15pstk+ Karyotype. We discuss potential genetic factors related to both Rb and polydactyly. Furthermore, there is a need for further exploration into the impact of chromosomal polymorphisms in Rb with polydactyly.

Exploring the impact of college graduates' place attachment on entrepreneurial intention upon returning to hometowns: A study based on the theory of planned behavior.

The issue of the continuing decline of rural areas caused by urbanization has become a global concern. Encouraging college graduates to return to their hometowns to start businesses is an important initiative for countries to achieve sustainable rural development. Drawing from the Theory of Planned Behavior (TPB), this study introduces two additional variables: place attachment and entrepreneurial self-efficacy. Through a series of three model refinements, a comprehensive theoretical framework has been formulated to elucidate Chinese college graduates' hometown-based entrepreneurial intention and behavior. The samples for this study were 1151 college graduates selected from diverse universities across China. This study aims to explore the influence of college graduates' hometown-based entrepreneurial intention using Structural Equation Modelling. This analytical approach illuminates how variables such as college graduates' place attachment, entrepreneurial self-efficacy, subjective norm for hometown-based entrepreneurship, and attitude towards hometown-based entrepreneurship affected their hometown-based entrepreneurial intention. The research findings reveal the following insights: (1) The overall levels of college graduates' place attachment and hometown-based entrepreneurial intention were relatively low. (2) College graduates' place attachment, entrepreneurial self-efficacy, subjective norm for hometown-based entrepreneurship, and attitude towards hometown-based entrepreneurship, had a positive impact on their hometown-based entrepreneurial intention. (3) College graduates' place attachment and subjective norm for hometown-based entrepreneurship had a significant impact on their hometown-based entrepreneurial intention through the mediating variable of entrepreneurial self-efficacy. This study then makes policy recommendations from theoretical and managerial aspects.

Pest recognition in microstates state: an improvement of YOLOv7 based on Spatial and Channel Reconstruction Convolution for feature redundancy and vision transformer with Bi-Level Routing Attention.

Introduction: In order to solve the problem of precise identification and counting of tea pests, this study has proposed a novel tea pest identification method based on improved YOLOv7 network. Methods: This method used MPDIoU to optimize the original loss function, which improved the convergence speed of the model and simplifies the calculation process. Replace part of the network structure of the original model using Spatial and Channel reconstruction Convolution to reduce redundant features, lower the complexity of the model, and reduce computational costs. The Vision Transformer with Bi-Level Routing Attention has been incorporated to enhance the flexibility of model calculation allocation and content perception. Results: The experimental results revealed that the enhanced YOLOv7 model significantly boosted Precision, Recall, F1, and mAP by 5.68%, 5.14%, 5.41%, and 2.58% respectively, compared to the original YOLOv7. Furthermore, when compared to deep learning networks such as SSD, Faster Region-based Convolutional Neural Network (RCNN), and the original YOLOv7, this method proves to be superior while being externally validated. It exhibited a noticeable improvement in the FPS rates, with increments of 5.75 HZ, 34.42 HZ, and 25.44 HZ respectively. Moreover, the mAP for actual detection experiences significant enhancements, with respective increases of 2.49%, 12.26%, and 7.26%. Additionally, the parameter size is reduced by 1.39 G relative to the original model. Discussion: The improved model can not only identify and count tea pests efficiently and accurately, but also has the characteristics of high recognition rate, low parameters and high detection speed. It is of great significance to achieve realize the intelligent and precise prevention and control of tea pests.

Combination of gold nanoclusters and silicon quantum dots for ratiometric fluorometry: One system, two mechanisms.

A ratiometric fluorometry based on silicon quantum dots (SiQDs) and gold nanoclusters (AuNCs) is constructed for detecting activity of butyrylcholinesterase (BChE) in human serum. By using thiobutyrylcholine iodide (BTCh) as the substrate of BChE-catalyzed hydrolysis reaction, variation of fluorescence emission from AuNCs is employed as an indicator of BChE activity since one of the hydrolysis products, thiocholine (TCh), would influence the aggregation state of AuNCs and consequently led to the change of fluorescence quantum efficiency of AuNCs. It is interesting that there are two mechanisms working for the fluorescence emission of aggregated AuNCs: aggregation-induced emission enhancement (AIEE) and aggregation-caused quenching (ACQ) with the presence of TCh at very low and higher concentration levels, respectively. Although both of these mechanisms can be utilized for sensing BChE, their opposite influence on the fluorescence emission of aggregated AuNCs should be worthy of attention, especially in the process of developing fluorescence methods for detecting trace targets by using AuNCs. In order to eliminate the fluctuation of fluorophotometer, SiQDs is chosen as the fluorophore to develop by ratiometric fluorescence methods in this work. Additionally, obvious aggregation of AuNCs induces significant decrease of inner filter effect (IFE) on the fluorescence emitted from SiQDs, while mild aggregation of AuNCs demonstrates little IFE. The linear ranges for detecting activity of BChE are 0.004 - 0.05 U/L and 0.5 - 20 U/L by ratiometric fluorometry based on the AIEE and ACQ, respectively. The very different responses originated from AIEE and ACQ of AuNCs would respectively make their own contributions to the determination of BChE activities at very low or high levels, which facilitate the developments of enhanced or quenched fluorescence methods. However, the detection of BChE activities at medium levels might suffer from the combination of AIEE and ACQ with ambiguous fractions. Therefore, it must be careful during the processes of developing and applying fluorescence methods based on the AIEE and ACQ of AuNCs, as well as the process of evaluating their analytical performance.

Knowledge mapping of spastic cerebral palsy. A bibliometric analysis of global research (2000-2022).

BACKGROUND: Cerebral palsy (CP) is characterized by abnormal pronunciation, posture, and movement. Spastic CP accounts for more than 70% of all CP. To date, there has been no bibliometric analysis to summarize study on spastic CP. Here, we aim to conduct a bibliometric analysis of spastic CP to summarize this field's knowledge structure, research hotspots, and frontiers. METHOD: Publications about spastic CP were searched utilizing the Web of Science Core Collection (WoSCC) database from 1 January 2000 to 30 November 2022, the WoSCC literature analysis wire, VOSviewer 1.6.18, CiteSpace 6.1.R4 and Online analysis platform for bibliometrics were used to conduct the analysis. RESULTS: A total of 3988 publications, consisting of 3699 articles and 289 reviews, were included in our study. The United States emerged as the most productive country, while Kathleen Univ Leuven was the most productive institution. The leading author was Desloovere K. A total of 238 journals contributed to this field, with Developmental medicine and child neurology being the leading journal. Important keywords and keyword clusters included Spastic cerebral palsy, Reliability, and Gross motor function. Keywords identified through burst detection indicated that hotspots in this field were management, randomized controlled trials, and definition. CONCLUSION: Based on the analysis of bibliometric on spastic CP over the past 20 years, the trends and the knowledge graph of the countries, institutions, authors, references, and the keywords have been identified, providing accurate and expedited insights into critical information and potentially new directions in the study of spastic CP.

Visualization of production and remediation of acetaminophen-induced liver injury by a carboxylesterase-2 enzyme-activatable near-infrared fluorescent probe.

Acetaminophen (APAP) overdose, also known as APAP poisoning, may directly result in hepatic injury, acute liver failure and even death. Nowadays, APAP-induced liver injury (AILI) has become an urgent public health issue in the developing world so the early accurate diagnosis and the revelation of underlying molecular mechanism of AILI are of great significance. As a major detoxifying organ, liver is responsible for metabolizing chemical substances, in which human carboxylesterase-2 (CES2) is present. Hence, we chose CES2 as an effective biomarker for evaluating AILI. By developing a CES2-activatable and water-soluble fluorescent probe PFQ-E with superior affinity (Km = 5.9 µM), great sensitivity (limit of detection = 1.05 ng/mL), near-infrared emission (655 nm) and large Stokes shift (135 nm), activity and distribution of CES2 in cells were determined or imaged effectively. More importantly, the APAP-induced hepatotoxicity and the underlying molecular mechanism of pathogenesis of AILI were investigated by measuring the "light-up" response of PFQ-E towards endogenous CES2 in vivo for the first time. Based on the superior performance of the probe PFQ-E for sensing CES2, we believe that it has broad potential in clinical diagnosis and therapy response evaluation of AILI.

π-Electron Fluctuation-Induced P+ /C- Ambiphilic Interaction for Intramolecular CAr -H Bond Activation.

Herein, we describe how computational mechanistic understanding has led directly to the discovery of new 2H-phosphindole for C-CAr bond activation and dearomatization reaction. We uncover an unexpected intramolecular C-H bond activation with a 2H-phosphindole derivative. This new intriguing experimental observation and further theoretical studies led to an extension of the reaction mechanism with 2H-phosphindole. Through DFT calculations, we confirm that within a five-membered ring, the polarizable PC3 unit orchestrates the formation of an electrophilic phosphorus atom (P+ ) and a nucleophilic carbon atom (C- ). This kinetically accessible ambiphilic phosphorus/carbon couple is spatially separated by geometric constraints, and their reactivity is modulated through structural resonance.

Navigating Technostress in primary schools: a study on teacher experiences, school support, and health.

The COVID-19 pandemic has led to a global shift toward online education, which has increased the use of technology for communication, management, and remote teaching. This study aimed to investigate how primary school teachers in China used technology during the Pandemic and to what extent they experienced Technostress, as well as the impact of Technostress on work-family conflicts and technology-induced health issues. A survey was conducted among 1,172 primary school teachers, and the results revealed that teachers exhibited a moderate to a high level of Technostress during the Pandemic, with differences observed in gender, age, and headteacher duties. Furthermore, Technostress was positively correlated with work-family conflicts and technology-induced health issues. Technology use intensity was found to directly impact work-family conflicts and personal health and indirectly impact them via the agency effects of Technostress. School support moderated the indirect relationship between technology use intensity and work-family conflicts and health issues, with higher levels of school support leading to less apparent impacts of technology intensity on work-family conflicts and personal health via the agency effect of Technostress. These findings provide timely insights for post-pandemic teacher training and technology management and suggest the importance of school support in promoting sustainable educational development.

Amniotic membrane transplantation combined with conjunctival flap covering surgery for the treatment of corneal perforations in fungal keratitis.

Purpose: To investigate the efficiency of amniotic membrane transplantation (AMT) combined with conjunctival flap covering surgery (CFCS) for patients with corneal perforations in fungal keratitis (FK). Methods: In this non-comparative, retrospective case series, 16 participants of corneal perforation in FK were successfully treated by a combination of multilayer AMT and bipedicle conjunctival flap with partial tenon's capsule. Corneal healing, recurrence of FK, visual acuity, and relevant complications were reported as outcome measures. Results: Sixteen patients (13 male, 3 female) had a mean age of 58.8 ± 10.3 (range 29-72) years. The mean diameter of corneal perforation was 1.9 ± 0.7 (range 0.5-2.8) mm. Corneal perforations healed and all the patients preserved their eyeballs. During the 11.0 ± 4.4 (range 6-18) months of follow-up, there was no recurrence of FK in any of these cases. Visual acuity improved in 15 eyes (93.8 %) and remained unchanged in 1 patient (6.3 %) who had no light perception when first admitted. All 6 patients who accepted secondary keratoplasty showed improved best corrected visual acuity of more than 4 lines. The most frequently found fungi were Aspergillus species (6 of 16, 37.5 %) and Fusarium species (4 of 16, 25.0 %), followed by 1 Scedosporium apiospermum (1 of 16, 6.3 %). Conclusions: Combination AMT with CFCS is a safe and effective surgery for patients with corneal perforations in FK, particularly where eye banks and fresh corneas are not available. This surgery could preserve the integrity of the eyeball and avoid the recurrence of FK. Besides, it provides a greater opportunity for further optical keratoplasty.

Numerical Reconstruction of Cyclist Impact Accidents: Can Helmets Protect the Head-Neck of Cyclists?

Cyclists are vulnerable road users and often suffer head-neck injuries in car-cyclist accidents. Wearing a helmet is currently the most prevalent protection method against such injuries. Today, there is an ongoing debate about the ability of helmets to protect the cyclists' head-neck from injury. In the current study, we numerically reconstructed five real-world car-cyclist impact accidents, incorporating previously developed finite element models of four cyclist helmets to evaluate their protective performances. We made comparative head-neck injury predictions for unhelmeted and helmeted cyclists. The results show that helmets could clearly lower the risk of severe (AIS 4+) brain injury and skull fracture, as assessed by the predicted head injury criterion (HIC), while a relatively limited decrease in AIS 4+ brain injury risk can be achieved in terms of the analysis of CSDM0.25. Assessment using the maximum principal strain (MPS0.98) and head impact power (HIP) criteria suggests that helmets could lower the risk of diffuse axonal injury and subdural hematoma of the cyclist. The helmet efficacy in neck protection depends on the impact scenario. Therefore, wearing a helmet does not seem to cause a significant neck injury risk level increase to the cyclist. Our work presents important insights into the helmet's efficacy in protecting the head-neck of cyclists and motivates further optimization of protective equipment.

Investigation of Conjunctival Goblet Cell and Tear MUC5AC Protein in Patients With Graves' Ophthalmopathy.

Purpose: The aim of this study was to investigate conjunctival goblet cell density (GCD) and tear mucin-5AC (MUC5AC) protein levels in patients with Graves' ophthalmopathy (GO) and their association with dry eye indicators. Methods: A total of 99 patients with GO (54 active, 45 inactive) and 40 healthy controls were recruited. Comprehensive ophthalmic examinations, including the external eye, ocular surface, GCD, and tear MUC5AC ELISA, were performed. The GCD examination was performed in temporal bulbar conjunctiva, including IVCM GCD by in vivo confocal microscopy (IVCM) and filled GCD of cytokeratin-7 and MUC5AC-positive co-immunomarkers by impression cytology. Tear MUC5AC protein was detected using samples extracted from Schirmer strips. Results: The GO group showed a significant decrease in IVCM GCD, filled GCD, and normalized tear MUC5AC protein compared to controls, with the active GO group showing the greatest decrease (all P < 0.05). Tear MUC5AC protein levels in GO correlated with those of IVCM GCD (r = 0.40, P < 0.001) and filled GCD (r = 0.54, P < 0.001, respectively). Higher ocular surface disease index (r = -0.22, P < 0.05; r = -0.20, P < 0.05; r = -0.21, P < 0.05) and lisamine green staining (r = -0.23, P < 0.05; r = -0.38, P < 0.001; r = -0.42, P < 0.001) were associated with lower tear MUC5AC protein levels, IVCM GCD, and filled GCD, respectively, which decreased with increasing clinical activity score (r = -0.24, P < 0.05; r = -0.28, P < 0.01; r = -0.27, P < 0.01) and conjunctival congestion score (r = -0.27, P < 0.01; r = -0.33, P < 0.001; r = -0.42, P < 0.001). Conclusions: The goblet cell count and tear MUC5AC protein in GO eyes were decreased, possibly due to ocular surface inflammation. Translational Relevance: This study observed the change of tear film mucin in GO patients.

A novel intramolecular charge transfer-based near-infrared fluorescent probe with large Stokes shift for highly sensitive detection of cysteine in vivo.

Cysteine (Cys) distribute widely in organisms as the crucial components of proteins, and play important roles in pathophysiological processes of human body. Low level of Cys might induce hepatic injury, edema and growth retardation, while superfluous level of Cys is found to be closely relevant to Alzheimer's and Parkinson's diseases. In this work, a novel near-infrared (NIR) fluorescent probe PFQ-C was developed for highly selective detection of Cys in living cells and mice by utilizing the cyclization removal reaction between acrylate group and Cys. The superior sensitivity (limit of detection, 0.036 µM), NIR emission (655 nm), large Stokes shift (135 nm) and low cytotoxicity of the probe highlight its broad potential for future clinical applications. The response mechanism of the probe towards Cys was clarified by spectroscopy, chromatography and theoretical calculation. In addition, results of fluorescence imaging of cells and mice revealed the good performance of the probe for monitoring the distributions and variations of Cys activity in vivo, which is very useful for the researches on diseases associated with Cys.

Effects of phosphine ligands in nickel-catalyzed decarbonylation reactions of lactone.

Due to the ubiquity of carbonyl compounds and the abundance of nickel on the earth, nickel-catalyzed decarbonylation has garnered increasing attention in recent years. This type of reaction has seen significant developments in various aspects; however, certain challenges concerning reactivity, selectivity, and transformation efficiency remain pressing and demand urgent resolution. In this study, we employed DFT calculations to investigate the mechanism of nickel-catalyzed decarbonylation reactions involving lactones, as well as the effects of phosphine ligands. Mechanically, Ni(0) first activates the C(acyl)-O bond of the lactone, followed by a decarbonylation step, and ultimately results in reductive elimination under carbonyl coordination to yield the product. Through a comprehensive examination of the electronic and steric effects of the phosphine ligands, we deduced that the electronic effect of the ligand plays a dominant role in the decarbonylation reaction. By enhancing the electron-withdrawing ability of the ligand, the energy barrier of the entire reaction can be significantly reduced. The obtained insights should be valuable for understanding the detailed mechanism and the role of phosphine ligands in nickel catalysis. Moreover, they offer crucial clues for the rational design of more efficient catalytic reactions.