ABSTRACT
A cascade Nazarov cyclization/dicycloexpansions reaction was developed for the precise synthesis of the angularly fused M/5/N (M = 5, 6; N = 4-9, 13) tricyclic skeletons. The prioritized expansion of the first ring played a critical role in the transformations, due to the release of ring strain, and the nature of the substituents present on the substrate is another influencing factor. This pioneering cascade reaction features broad substrates scope (33 examples), short reaction time, exceptional yields (up to 95%), and remarkable regioselectivities (> 20:1). Exploiting the synthetic application of this cascade reaction, we successfully executed a succinct total synthesis of nominal madreporanone for the first time.
ABSTRACT
An asymmetric intramolecular spiro-amination to high steric hindering α-C-H bond of 1,3-dicarbonyl via nitrene transfer using inactive aryl azides has been carried out by developing a novel Cp*Ir(III)-SPDO (spiro-pyrrolidine oxazoline) catalyst, thereby enabling the first successful construction of structurally rigid spiro-quaternary indolinone cores with moderate to high yields and excellent enantioselectivities. DFT computations support the presence of double bridging H-F bonds between [SbF6]- and both the ligand and substrate, which favors the plane-differentiation of the enol π-bond for nitrenoid attacking. These findings open up numerous opportunities for the development of new asymmetric nitrene transfer systems.
ABSTRACT
Porcine deltacoronavirus (PDCoV) is an emerging swine enteric coronavirus with zoonotic potential. The coronavirus spike (S) glycoprotein, especially the S1 subunit, mediates viral entry by binding to cellular receptors. However, the functional receptor of PDCoV remains poorly understood. In this study, we used the soluble PDCoV S1 protein as bait to capture the S1-binding cellular transmembrane proteins in combined immunoprecipitation and mass spectrometry analyses. A single guide RNA screen identified d-glucuronyl C5-epimerase (GLCE), a heparan sulfate-modifying enzyme, as a proviral host factor for PDCoV infection. GLCE knockout significantly inhibited the attachment and internalization stages of PDCoV infection. We also demonstrated the interaction between GLCE and PDCoV S with coimmunoprecipitation in both an overexpression system and PDCoV-infected cells. GLCE could be localized to the cell membrane, and an anti-GLCE antibody suppressed PDCoV infection. Although GLCE expression alone did not render nonpermissive cells susceptible to PDCoV infection, GLCE promoted the binding of PDCoV S to porcine amino peptidase N (pAPN), acting synergistically with pAPN to enhance PDCoV infection. In conclusion, our results demonstrate that GLCE is a novel cell-surface factor facilitating PDCoV entry and provide new insights into PDCoV infection. IMPORTANCE: The identification of viral receptors is of great significance, potentially extending our understanding of viral infection and pathogenesis. Porcine deltacoronavirus (PDCoV) is an emerging enteropathogenic coronavirus with the potential for cross-species transmission. However, the receptors or coreceptors of PDCoV are still poorly understood. The present study confirms that d-glucuronyl C5-epimerase (GLCE) is a positive regulator of PDCoV infection, promoting viral attachment and internalization. The anti-GLCE antibody suppressed PDCoV infection. Mechanically, GLCE interacts with PDCoV S and promotes the binding of PDCoV S to porcine amino peptidase N (pAPN), acting synergistically with pAPN to enhance PDCoV infection. This work identifies GLCE as a novel cell-surface factor facilitating PDCoV entry and paves the way for further insights into the mechanisms of PDCoV infection.
Subject(s)
Deltacoronavirus , Spike Glycoprotein, Coronavirus , Virus Internalization , Animals , Spike Glycoprotein, Coronavirus/metabolism , Spike Glycoprotein, Coronavirus/genetics , Swine , Deltacoronavirus/metabolism , Humans , Carbohydrate Epimerases/metabolism , Carbohydrate Epimerases/genetics , Protein Binding , Coronavirus Infections/virology , Coronavirus Infections/metabolism , Coronavirus Infections/veterinary , Swine Diseases/virology , Swine Diseases/metabolism , Cell Line , Receptors, Virus/metabolism , Virus Attachment , HEK293 Cells , Cell Membrane/metabolism , Cell Membrane/virologyABSTRACT
A protocol for the electrooxidative [3+2] annulation to generate indolo[2,3-b]indoles in an undivided cell is reported. It exhibits good yields with excellent regioselectivities and tolerates various functional groups without external chemical oxidants. Cyclic voltammetry and density functional theory calculations indicate that the [3+2] annulation is initiated by the simultaneous anodic oxidation of indole and aniline derivatives, and the step to determine the rate relies on the combination of radical cations.
ABSTRACT
The field of computational pathology[1,2] has witnessed remarkable progress in the development of both task-specific predictive models and task-agnostic self-supervised vision encoders[3,4]. However, despite the explosive growth of generative artificial intelligence (AI), there has been limited study on building general purpose, multimodal AI assistants and copilots[5] tailored to pathology. Here we present PathChat, a vision-language generalist AI assistant for human pathology. We build PathChat by adapting a foundational vision encoder for pathology, combining it with a pretrained large language model and finetuning the whole system on over 456,000 diverse visual language instructions consisting of 999,202 question-answer turns. We compare PathChat against several multimodal vision language AI assistants and GPT4V, which powers the commercially available multimodal general purpose AI assistant ChatGPT-4[7]. PathChat achieved state-of-the-art performance on multiple-choice diagnostic questions from cases of diverse tissue origins and disease models. Furthermore, using open-ended questions and human expert evaluation, we found that overall PathChat produced more accurate and pathologist-preferable responses to diverse queries related to pathology. As an interactive and general vision-language AI Copilot that can flexibly handle both visual and natural language inputs, PathChat can potentially find impactful applications in pathology education, research, and human-in-the-loop clinical decision making.
ABSTRACT
Background: Recovery time is a crucial factor in ensuring the safety and effectiveness of both patients and endoscopy centers. Propofol is often preferred due to its fast onset and minimal side effects. Remimazolam is a new intravenous sedative agent, characterized by its rapid onset of action, quick recovery and organ-independent metabolism. Importantly, its effect can be specifically antagonized by flumazenil. The primary goal of this study is to compare the recovery time of remimazolam besylate and propofol anesthesia during endoscopic procedures in elderly patients. Methods: 60 patients aged 65-95 years who underwent gastrointestinal endoscopy were randomly and equally assigned to two groups: the remimazolam group (Group R) and the propofol group (Group P). The primary measure was the recovery time, defined as the time from discontinuing remimazolam or propofol until reaching an Observer's Assessment of Alertness and Sedation scale (OAA/S) score of 5 (responds readily to name spoken in normal tone). The time required to achieve an OAA/S score of 3 (responds after name spoken loudly or repeatedly along with glazed marked ptosis) was also recorded and compared. Results: The recovery time for Group R (2.6 ± 1.6 min) was significantly shorter than that for Group P (10.8 ± 3.0 min), with a 95% confidence interval (CI): 6.949-9.431 min, p <0.001. Similarly, the time to attain an OAA/S score of 3 was significantly less in Group R (1.6 ± 0.9 min) compared to Group P (9.6 ± 2.6 min), with a 95% CI: 6.930-8.957 min, p <0.001. Conclusion: Our study demonstrated that remimazolam anesthesia combined with flumazenil antagonism causes a shorter recovery time for elderly patients undergoing gastrointestinal endoscopy compared to propofol. Remimazolam followed by flumazenil antagonism provides a promising alternative to propofol for geriatric patients, particularly during gastrointestinal endoscopy.
Subject(s)
Anesthesia Recovery Period , Benzodiazepines , Endoscopy, Gastrointestinal , Hypnotics and Sedatives , Propofol , Humans , Aged , Propofol/administration & dosage , Male , Female , Aged, 80 and over , Endoscopy, Gastrointestinal/methods , Hypnotics and Sedatives/administration & dosage , Hypnotics and Sedatives/adverse effects , Benzodiazepines/therapeutic useABSTRACT
Bridged chiral biaryls are axially chiral compounds with a medium-sized ring connecting the two arenes. Compared with plentiful methods for the enantioselective synthesis of biaryl compounds, synthetic approaches for this subclass of bridged atropisomers are limited. Here we show an atroposelective synthesis of 1,3-diaxial bridged eight-membered terphenyl atropisomers through an Co/SPDO (spirocyclic pyrrolidine oxazoline)-catalyzed aerobic oxidative coupling/desymmetrization reaction of prochiral phenols. This catalytic desymmetric process is enabled by combination of an earth-abundant Co(OAc)2 and a unique SPDO ligand in the presence of DABCO (1,4-diaza[2.2.2]bicyclooctane). An array of diaxial bridged terphenyls embedded in an azocane can be accessed in high yields (up to 99%) with excellent enantio- (>99% ee) and diastereoselectivities (>20:1 dr).
ABSTRACT
Purpose: To explore the effect of coronavirus disease 2019 (COVID-19) infection on neonates in plateau regions. Methods: Cases of newborns born to pregnant women infected with COVID-19 who received prenatal care or treatment at the Women and Children's Hospital of the Tibet Autonomous Region and the Lhasa People's Hospital between January 2020 and December 2022 (infected group) and newborns born to healthy pregnant women (non-infected group) who were included by age, underlying disease and length of hospital stay were retrospectively collected. According to the inclusion and exclusion criteria, 381 patients in the infected group and 314 patients in the non-infected group were included in the study. Results: The results of multivariate analysis showed that admission to the neonatal intensive care unit (OR = 3.342, 95% CI = 1.564-6.764), shortness of breath (OR = 2.853, 95% CI = 1.789-3.154), irregular breathing (OR = 2.465, 95% CI = 1.879-4.112) and neonatal jaundice (OR = 2.324, 95% CI = 1.989-2.445) were the factors influencing the low Apgar scores of neonates in the infected group (all P < 0.05). Conclusion: Neonates born to pregnant women infected with COVID-19 had lower Apgar scores and higher incidences of complications, such as shortness of breath, groaning, irregular breathing and neonatal jaundice, than newborns born to pregnant women not infected with COVID-19.
ABSTRACT
The accelerated adoption of digital pathology and advances in deep learning have enabled the development of robust models for various pathology tasks across a diverse array of diseases and patient cohorts. However, model training is often difficult due to label scarcity in the medical domain, and a model's usage is limited by the specific task and disease for which it is trained. Additionally, most models in histopathology leverage only image data, a stark contrast to how humans teach each other and reason about histopathologic entities. We introduce CONtrastive learning from Captions for Histopathology (CONCH), a visual-language foundation model developed using diverse sources of histopathology images, biomedical text and, notably, over 1.17 million image-caption pairs through task-agnostic pretraining. Evaluated on a suite of 14 diverse benchmarks, CONCH can be transferred to a wide range of downstream tasks involving histopathology images and/or text, achieving state-of-the-art performance on histology image classification, segmentation, captioning, and text-to-image and image-to-text retrieval. CONCH represents a substantial leap over concurrent visual-language pretrained systems for histopathology, with the potential to directly facilitate a wide array of machine learning-based workflows requiring minimal or no further supervised fine-tuning.
Subject(s)
Language , Machine Learning , Humans , WorkflowABSTRACT
Quantitative evaluation of tissue images is crucial for computational pathology (CPath) tasks, requiring the objective characterization of histopathological entities from whole-slide images (WSIs). The high resolution of WSIs and the variability of morphological features present significant challenges, complicating the large-scale annotation of data for high-performance applications. To address this challenge, current efforts have proposed the use of pretrained image encoders through transfer learning from natural image datasets or self-supervised learning on publicly available histopathology datasets, but have not been extensively developed and evaluated across diverse tissue types at scale. We introduce UNI, a general-purpose self-supervised model for pathology, pretrained using more than 100 million images from over 100,000 diagnostic H&E-stained WSIs (>77 TB of data) across 20 major tissue types. The model was evaluated on 34 representative CPath tasks of varying diagnostic difficulty. In addition to outperforming previous state-of-the-art models, we demonstrate new modeling capabilities in CPath such as resolution-agnostic tissue classification, slide classification using few-shot class prototypes, and disease subtyping generalization in classifying up to 108 cancer types in the OncoTree classification system. UNI advances unsupervised representation learning at scale in CPath in terms of both pretraining data and downstream evaluation, enabling data-efficient artificial intelligence models that can generalize and transfer to a wide range of diagnostically challenging tasks and clinical workflows in anatomic pathology.
Subject(s)
Artificial Intelligence , WorkflowABSTRACT
In recent years, the field of antibody drug conjugates (ADC) has seen a resurgence, largely driven by the clinical benefit observed in patients treated with ADCs incorporating camptothecin-based topoisomerase I inhibitor payloads. Herein, we present the development of a novel camptothecin ZD06519 (FD1), which has been specifically designed for its application as an ADC payload. A panel of camptothecin analogs with different substituents at the C-7 and C-10 positions of the camptothecin core was prepared and tested in vitro. Selected compounds spanning a range of potency and hydrophilicity were elaborated into drug-linkers, conjugated to trastuzumab, and evaluated in vitro and in vivo. ZD06519 was selected on the basis of its favorable properties as a free molecule and as an antibody conjugate, which include moderate free payload potency (â¼1 nmol/L), low hydrophobicity, strong bystander activity, robust plasma stability, and high-monomeric ADC content. When conjugated to different antibodies using a clinically validated MC-GGFG-based linker, ZD06519 demonstrated impressive efficacy in multiple cell line-derived xenograft models and noteworthy tolerability in healthy mice, rats, and non-human primates.
Subject(s)
Camptothecin , Immunoconjugates , Xenograft Model Antitumor Assays , Camptothecin/pharmacology , Camptothecin/chemistry , Immunoconjugates/pharmacology , Immunoconjugates/chemistry , Animals , Humans , Mice , Cell Line, Tumor , Drug Design , Female , RatsABSTRACT
Purpose: Pelvic floor disorder (PFD) seriously affects the everyday life of women. This cross-sectional study aimed to evaluate the prevalence and risk factors for postpartum PFD in women living in the Tibet Autonomous Region (TAR). Methods: Parous women who attended the outpatient gynaecology clinic at our hospital between June 2022 and August 2022 were screened in this study. The demographic and clinical data of these women were collected. Their pelvic floor functions were evaluated via a pelvic organ prolapse (POP) quantification examination, the Pelvic Floor Distress Inventory Questionnaire-20 (PFDI-20) and the Overactive Bladder Symptom Score (OABSS). Results: A total of 201 women were included in this study, of whom 81.09% (163/201) were Tibetan. Twenty-seven women (13.43%) were diagnosed with POP stage ≥2 and 27 women (13.43%) with an OABSS score ≥3. The median PFDI-20 total score was 4.17 (range 0-43.75). Han women (n = 38) in the TAR had much lower PFDI-20 total scores, compared with Tibetan women (n = 163) (p < 0.05). The results of the multiple linear regression models showed that the PFDI-20 scores obtained from women living in the TAR were closely related to parity, history of heavy weight lifting, age, history of instrumental deliveries, ethnicity and number of caesarean sections. Conclusion: Pelvic floor disorder is common among parous women living in the TAR. Ethnicity, parity, history of heavy weight lifting, age, history of instrumental deliveries and number of caesarean sections are the factors closely related to the PFDI-20 scores.
ABSTRACT
Purpose Renal cell carcinoma (RCC) is one of the most common malignant tumors of the urinary system, which has high metastasis. MicroRNAs (miRNAs) have been reported to participate in RCC progression. The present study aimed to understand the biological role and mechanism of miR-378a-3p in RCC. Methods RT-qPCR assay was used to assess miR-378a-3p and transducer of ERBB2 (TOB2) expression in RCC tissues and cell lines. CCK-8, clone formation, scratch, and transwell assays were carried out to evaluate cell proliferation, migration, and invasion. Furthermore, the target genes of miR-378a-3p were predicted by the online bioinformatics databases. Dual-luciferase reporter assay was used to validate the relationship between miR-378a-3p and TOB2. Results miR-378a-3p was highly expressed in RCC tissues and RCC cell lines. Besides, miR-378a-3p accelerated the progression of RCC by mediating cell proliferation, migration and invasion. More importantly, TOB2 was confirmed as a potential target gene of miR-378a-3p. The results of loss-of-function experiments showed that inhibition of TOB2 reversed the inhibitory roles of miR-378a-3p inhibitor on RCC progression. Conclusions miR-378a-3p promoted cell proliferation, migration and invasion through regulating TOB2 in RCC, which indicated a promising target for the treatment of RCC (AU)
Subject(s)
Humans , Carcinoma, Renal Cell/genetics , Carcinoma, Renal Cell/metabolism , Kidney Neoplasms/genetics , Kidney Neoplasms/metabolism , MicroRNAs/metabolism , Cell Line, Tumor , Cell Movement , Cell Proliferation , Gene Expression Regulation, NeoplasticABSTRACT
Objective @# To investigate the effect of micro/nano hierarchical structures on the adhesion and proliferation of MC3T3-E1 cells, evaluate the drug delivery potential of titanium surfaces, and provide a reference for the modification of selected areas of titanium surfaces to enhance drug delivery and slow drug release. @*Methods @# Pure titanium samples (10 mm in diameter and 2.5 mm in thickness) were randomly divided into a polished group (T), anodized group (TO), and micro/nano hierarchical structure group (FTO) according to the surface treatment of the titanium. The T group was polished, the TO group was treated with anodic oxidation technology, and the FTO group was treated by femtosecond laser etching combined with anodic oxidation technology. The three surface morphologies were observed by scanning electron microscopy (SEM), the wettability of the surface was measured by the contact angle, and the surface chemical composition was analyzed by X-ray energy dispersive spectroscopy (EDS). The depth of the FTO structure and the surface roughness were measured by confocal laser scanning microscopy (CLSM). MC3T3-E1 cell adhesion proliferation and differentiation on the surface of each group of samples was assessed by immunofluorescence staining, CCK-8, and semiquantitative analysis of Alizarin staining. A freeze-drying method was applied to load recombinant human bone morphogenetic protein-2 (rhBMP-2), and an enzyme-linked immunosorbent assay (ELISA) was used to assess the drug-loading potential of different surface structures. @* Results@#SEM revealed that the surface of T group titanium plates showed uniform polishing marks in the same direction. The surface of the TO group was a nanoscale honeycomb-like titanium dioxide (TiO2) nanotube structure, and the FTO group formed a regular and ordered micro/nano layered structure. The contact angle of the FTO group was the smallest at 32° ± 1.7°. Its wettability was the best. The average depth of the first-level structure circular pores was 93.6 μm, and the roughness was 1.5-2 μm. The TO and FTO groups contained a high percentage of oxygen, suggesting TiO2 nanotube formation. The FTO group had the most significant surface cell proliferation (P<0.001) and the largest cell adhesion surface area (P<0.05). rhBMP-2 was slowly released for 14 d after loading in the FTO group and promoted extracellular matrix mineralization (P<0.001). @*Conclusion @#Titanium surface microprepared hierarchical structure has the effect of promoting MC3T3-E1 cell adhesion, proliferation, and osteogenic differentiation with drug loading potential, which is a new method of titanium surface treatment.