Regioselective Arylation of Amidoaryne Precursors via Ag-Mediated Intramolecular Oxy-Argentation.

An unprecedented silver-mediated intramolecular oxy-argentation of 3-amidoaryne precursors that quickly generates a heteroarylsilver species is developed. AgF acts as both a stoichiometric fluoride source and a reagent for the formation of a benzoxazolylsilver intermediate via aryne generation. Pd-catalyzed coupling reactions of (hetero)aryl iodides with a silver species, generated in situ, allow for the synthesis of various C7-arylated benzoxazoles. As a result, an aryl group is selectively introduced into the meta-position of 3-amidobenzyne precursors. Mechanistic studies have indicated the presence of a benzoxazolylsilver intermediate and revealed that the reaction proceeds via an intramolecular oxy-argentation process, which is initiated by a direct fluoride attack on the silyl group.

Prediction models for post-thrombectomy brain edema in patients with acute ischemic stroke: a systematic review and meta-analysis.

Objective: The objective of this study is to systematically evaluate prediction models for post-thrombectomy brain edema in acute ischemic stroke (AIS) patients. This analysis aims to equip clinicians with evidence-based guidance for the selection of appropriate prediction models, thereby facilitating the early identification of patients at risk of developing brain edema post-surgery. Methods: A comprehensive literature search was conducted across multiple databases, including PubMed, Web of Science, Embase, The Cochrane Library, CNKI, Wanfang, and Vip, aiming to identify studies on prediction models for post-thrombectomy brain edema in AIS patients up to January 2023. Reference lists of relevant articles were also inspected. Two reviewers independently screened the literature and extracted data. The Prediction Model Risk of Bias Assessment Tool (PROBAST) and the Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis (TRIPOD) guidelines were employed to assess study bias and literature quality, respectively. We then used random-effects bivariate meta-analysis models to summarize the studies. Results: The review included five articles, yielding 10 models. These models exhibited a relatively high risk of bias. Random effects model demonstrated that the AUC was 0.858 (95% CI 0.817-0.899). Conclusion: Despite the promising discriminative ability shown by studies on prediction models for post-thrombectomy brain edema in AIS patients, concerns related to a high risk of bias and limited external validation remain. Future research should prioritize the external validation and optimization of these models. There is an urgent need for large-scale, multicenter studies to develop robust, user-friendly models for real-world clinical application. Systematic review registration: https://www.crd.york.ac.uk, unique Identifier: CRD42022382790.

The support dilemma of stroke inpatients and family caregivers under COVID-19 prevention and control: a qualitative study in China.

China has implemented a strict isolation system in hospitals since the COVID-19 pandemic, that adversely affected the psychology of inpatients and their caregivers. Face-to-face, semi-structured interviews with 22 stroke inpatients from two municipal hospitals were conducted to explore the psychological, emotional and related support needs of stroke inpatients and their family caregivers under this environment. Results which showed that external support for stroke inpatients and their family caregivers was insufficient highlight the necessity for developing specific nursing interventions that meet the psychological and emotional needs of inpatients and the caregivers.

Colorectal cancer organoid models uncover oxaliplatin-resistant mechanisms at single cell resolution.

PURPOSE: Oxaliplatin-based chemotherapy is a standard treatment for advanced colorectal cancer (CRC) patients. However, chemoresistance-induced resistance is an essential cause for mortality. Therefore, it is necessary to study the mechanism of drug resistance in CRC. METHODS: Here, we established two strains of patient-derived organoids (PDOs) selected from oxaliplatin-resistant and treatment-naïve CRC patients. To dissect the drug-resistant mechanisms, these CRC-PDOs were subjected to single-cell RNA sequencing (scRNA-Seq). RESULTS: We found that the drug sensitivity test outcome from these organoids subjected to oxaliplatin and 5-FU exposure was consistent with the clinic readout. CRC-PDOs well recapitulated the morphology and histology of their parental biopsies based on HE and IHC staining of pathological biomarkers. The scRNA-Seq data filtered drug-resistant cell populations and related signaling pathways (e.g. oxidative phosphorylation and ATP metabolic process). The data also revealed several putative drug resistant-driven genes (STMN1, VEGFA and NDRG1) and transcription factors (E2F1, BRCA1, MYBL2, CDX2 and CDX1). CONCLUSION: We generated an oxaliplatin-resistant CRC organoid model that was employed to provide potential therapeutic targets for treating CRC patients exhibiting oxaliplatin-resistance.

Defining the ultrastructure of the hematopoietic stem cell niche by correlative light and electron microscopy.

The blood system is supported by hematopoietic stem and progenitor cells (HSPCs) found in a specialized microenvironment called the niche. Many different niche cell types support HSPCs, however how they interact and their ultrastructure has been difficult to define. Here, we show that single endogenous HSPCs can be tracked by light microscopy, then identified by serial block-face scanning electron microscopy (SBEM) at multiscale levels. Using the zebrafish larval kidney marrow (KM) niche as a model, we followed single fluorescently labeled HSPCs by light sheet microscopy, then confirmed their exact location in a 3D SBEM dataset. We found a variety of different configurations of HSPCs and surrounding niche cells, suggesting there could be functional heterogeneity in sites of HSPC lodgement. Our approach also allowed us to identify dopamine beta-hydroxylase (dbh) positive ganglion cells as a previously uncharacterized functional cell type in the HSPC niche. By integrating multiple imaging modalities, we could resolve the ultrastructure of single rare cells deep in live tissue and define all contacts between an HSPC and its surrounding niche cell types.

[Ecosystem structure and function of Sanmen Bay based on Ecopath model.] / 基于Ecopath模型的三门湾生态系统结构与功能.

Ecosystem structure determines material circulation, energy flow, and system function. Based on field investigation data in the Sanmen Bay, East China Sea from 2017 to 2018, ecological channel model was constructed by Ecopath, describing energy flow routes and functional characteristics of the Sanmen Bay ecosystem. Results showed that grazing food chain was the main energy circulation channel, and the trophic level of each functional group ranged from 1 to 3.80. Energy flow of the system was mainly concentrated in the first five levels, with an average energy conversion efficiency of 13.0%. Energy conversion efficiency was 12.8% and 14.5% from primary producers and debris, respectively. Connectance index (CI) and system omnivory index (SOI) were 0.40 and 0.24 respectively. Finn's cycling index (FIC) was 0.40, and Finn's mean path length (MPL) was 2.06. The ratio of total primary productivity to total respiration was 13.59. In conclusion, Sanmen Bay ecosystem was immature in material circulation and energy flow. This work is helpful to understand the structural and functional traits of coastal ecosystems in China.

Integration of a Metal-Organic Framework Film with a Tubular Whispering-Gallery-Mode Microcavity for Effective CO2 Sensing.

Carbon dioxide (CO2) sensing using an optical technique is of great importance in the environment and industrial emission monitoring. However, limited by the poor specific adsorption of gas molecules as well as insufficient coupling efficiency, there is still a long way to go toward realizing a highly sensitive optical CO2 gas sensor. Herein, by combining the advantages of a whispering-gallery-mode microcavity and a metal-organic framework (MOF) film, a porous functional microcavity (PF-MC) was fabricated with the assistance of the atomic layer deposition technique and was applied to CO2 sensing. In this functional composite, the rolled-up microcavity provides the ability to tune the propagation of light waves and the electromagnetic coupling with the surroundings via an evanescent field, while the nanoporous MOF film contributes to the specific adsorption of CO2. The composite demonstrates a high sensitivity of 188 nm RIU-1 (7.4 pm/% with respect to the CO2 concentration) and a low detection limit of ∼5.85 × 10-5 RIU. Furthermore, the PF-MC exhibits great selectivity to CO2 and outstanding reproducibility, which is promising for the next-generation optical gas sensing devices.

Aortic coarctation with cardiac fibroma in a young patient: a case report.

BACKGROUND: Cardiac fibroma and aortic coarctation are rarely observed concomitantly in the same patient. We report a case of cardiac fibroma with aortic coarctation treated with a hybrid surgical procedure. To the best of our knowledge, this is the first case of these two abnormalities existing in one patient. CASE SUMMARY: A 22-year-old female patient visited the clinic with a 10-year history of hypertension. Physical examination revealed blood pressure of the upper extremities 50 mmHg higher than that of the lower extremities. Computed tomography angiography revealed a post-ductal-type aortic coarctation at the beginning segment of the descending aorta along with a 7.7 cm × 5.1 cm left ventricular mass. Transthoracic echocardiogram showed a mass at the middle segments of the lateral wall and apex and posterior wall of the left ventricle. Cardiac magnetic resonance imaging also showed the mass with hypointense signal on T1, hyperintense signal on T2, and intense signal on late gadolinium enhancement. No evidences of metastatic lesions were observed on 18F-fluorodeoxyglucose positron emission tomography. The patient underwent a hybrid surgery involving aortic stent implantation and complete left ventricular mass removal. The gradient between stenosis returned to <10 mmHg after the procedure. Pathologic findings revealed cardiac fibroma. DISCUSSION: It is rare to encounter a patient suffering from both cardiac fibroma and aortic coarctation. No evidences indicated a single cause or syndrome resulting in the coexistence of these two abnormalities. A hybrid surgery involving aortic stent implantation and complete cardiac mass resection could optimize the treatment in such cases.

Flying Squirrel-Inspired Motion Control of a Light-Deformed Pt-PAzoMA Micromotor through Drag Force Manipulation.

Micromotors require stable and precise motion control for complex tasks such as microsurgery, drug delivery in vivo, or environmental monitoring ex vivo. However, a continuous control signal is needed for micromotors to achieve motion control during their whole journey, which hinders their application in areas where external control stimuli are limited or unavailable. Fortunately, nature suggests an excellent solution that flying squirrel exhibits motion tuning capability by deforming itself when jumping off a tall tree. Inspired by this, we propose a Pt-PAzoMA Janus micromotor that precisely changes its shape (from a spherical shape to an elliptical shape) under a brief light signal (450 nm) and maintains this deformation until next signal reception. The deformed elliptical micromotor performs relatively low-speed motion compared to the spherical one, which is further confirmed by massive simulation results. In addition, by investigating motion behavior experimentally and theoretically, it is proved that the motion modulation is caused by the drag force changing brought from the deformation. This method represents a different route to regulate the motion of micromotors without a continuous signal, which is useful in application scenarios where the environmental control signal is inaccessible/limited or long-time operation with minimum energy input is required to maintain motion manipulation. With further function modification, this kind of shape-changing micromotor has potential in optimizing drug diffusion efficiency by speed altering and long-term monitoring at the diseased area by confining the active range of the micromotor in the targeted area through deformation.