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This article provides an in-depth review of computational methods for predicting transcriptional regulators (TRs) with query gene sets. Identification of TRs is of utmost importance in many biological applications, including but not limited to elucidating biological development mechanisms, identifying key disease genes, and predicting therapeutic targets. Various computational methods based on next-generation sequencing (NGS) data have been developed in the past decade, yet no systematic evaluation of NGS-based methods has been offered. We classified these methods into two categories based on shared characteristics, namely library-based and region-based methods. We further conducted benchmark studies to evaluate the accuracy, sensitivity, coverage, and usability of NGS-based methods with molecular experimental datasets. Results show that BART, ChIP-Atlas, and Lisa have relatively better performance. Besides, we point out the limitations of NGS-based methods and explore potential directions for further improvement.
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Computational Biology , High-Throughput Nucleotide Sequencing , High-Throughput Nucleotide Sequencing/methods , Computational Biology/methods , Humans , Transcription Factors/genetics , Transcription Factors/metabolism , Gene Expression RegulationABSTRACT
Revealing low-dimensional material growth dynamics is critical for crystal growth engineering. However, in a practical high-temperature growth system, the crystal growth process is a black box because of the lack of heat-resistant imaging tools. Here, we develop a heat-resistant optical microscope and embed it in a chemical vapor deposition (CVD) system to investigate two-dimensional (2D) crystal growth dynamics. This in situ optical imaging CVD system can tolerate temperatures of ≤900 °C with a spatial resolution of â¼1 µm. The growth of monolayer MoS2 crystals was studied as a model for 2D crystal growth. The nucleation and growth process have been imaged. Model analysis and simulation have revealed the growth rate, diffusion coefficient, and spatial distribution of the precursor. More importantly, a new vertex-kink-ledge model has been suggested for monolayer crystal growth. This work provides a new technique for in situ microscopic imaging at high temperatures and fundamental insight into 2D crystal growth.
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Highly active nonprecious-metal single-atom catalysts (SACs) toward catalytic transfer hydrogenation (CTH) of α,ß-unsaturated aldehydes are of great significance but still are deficient. Herein, we report that Zn-N-C SACs containing Zn-N3 moieties can catalyze the conversion of cinnamaldehyde to cinnamyl alcohol with a conversion of 95.5% and selectivity of 95.4% under a mild temperature and atmospheric pressure, which is the first case of Zn-species-based heterogeneous catalysts for the CTH reaction. Isotopic labeling, in situ FT-IR spectroscopy, and DFT calculations indicate that reactants, coabsorbed at the Zn sites, proceed CTH via a "Meerwein-Ponndorf-Verley" mechanism. DFT calculations also reveal that the high activity over Zn-N3 moieties stems from the suitable adsorption energy and favorable reaction energy of the rate-determining step at the Zn active sites. Our findings demonstrate that Zn-N-C SACs hold extraordinary activity toward CTH reactions and thus provide a promising approach to explore the advanced SACs for high-value-added chemicals.
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BACKGROUND: Neoadjuvant therapy followed by surgery has become the standard of care for locally advanced esophageal squamous cell carcinoma (ESCC) and accurate pathological response assessment is critical to assess the therapeutic efficacy. However, it can be laborious and inconsistency between different observers may occur. Hence, we aim to develop an interpretable deep-learning model for efficient pathological response assessment following neoadjuvant therapy in ESCC. METHODS: This retrospective study analyzed 337 ESCC resection specimens from 2020-2021 at the Pudong-Branch (Cohort 1) and 114 from 2021-2022 at the Puxi-Branch (External Cohort 2) of Fudan University Shanghai Cancer Center. Whole slide images (WSIs) from these two cohorts were generated using different scanning machines to test the ability of the model in handling color variations. Four pathologists independently assessed the pathological response. The senior pathologists annotated tumor beds and residual tumor percentages on WSIs to determine consensus labels. Furthermore, 1850 image patches were randomly extracted from Cohort 1 WSIs and binarily classified for tumor viability. A deep-learning model employing knowledge distillation was developed to automatically classify positive patches for each WSI and estimate the viable residual tumor percentages. Spatial heatmaps were output for model explanations and visualizations. RESULTS: The approach achieved high concordance with pathologist consensus, with an R^2 of 0.8437, a RAcc_0.1 of 0.7586, a RAcc_0.3 of 0.9885, which were comparable to two senior pathologists (R^2 of 0.9202/0.9619, RAcc_0.1 of 8506/0.9425, RAcc_0.3 of 1.000/1.000) and surpassing two junior pathologists (R^2 of 0.5592/0.5474, RAcc_0.1 of 0.5287/0.5287, RAcc_0.3 of 0.9080/0.9310). Visualizations enabled the localization of residual viable tumor to augment microscopic assessment. CONCLUSION: This work illustrates deep learning's potential for assisting pathological response assessment. Spatial heatmaps and patch examples provide intuitive explanations of model predictions, engendering clinical trust and adoption (Code and data will be available at https://github.com/WinnieLaugh/ESCC_Percentage once the paper has been conditionally accepted). Integrating interpretable computational pathology could help enhance the efficiency and consistency of tumor response assessment and empower precise oncology treatment decisions.
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Soft-lithography is widely used to fabricate microstructured surfaces on plastics and elastomers for designable physical properties such as wetting and adhesions. However, it remains a big challenge to construct high-aspect-ratio microstructures on the surface of hydrogels due to the difficulty in demolding from the gel with low strength and stiffness. Demonstrated here is the engineering of tough hydrogels by soft-lithography to form well-defined micropillars. The mechanical properties of poly(acrylamide-co-methacrylic acid) hydrogels with dense hydrogen-bond associations severely depend on temperature, with Young's modulus increasing from 8.1 MPa at 15 °C to 821.8 MPa at -30 °C, enabling easy demolding at low temperatures. Arrays of micropillars are maintained on the surface of the gel, and can be used at room temperature when the gel restores soft and stretchable. The hydrogel also exhibits good shape-memory property, favoring tailoring the morphology with a switchable tilt angle of micropillars. Consequently, the hydrogel shows tunable wetting and adhesion properties, as manifested by varying contact angles and adhesion strengths. These surface properties can also be tuned by geometry and arrangement of micropillars. This facile strategy by harnessing tunable viscoelasticity of supramolecular hydrogels should be applicable to other soft materials, and broaden their applications in biomedical and engineering fields.
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PtIr-based nanostructures are fascinating materials for application in bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysis. However, the fabrication of PtIr nanocatalysts with clear geometric features and structural configurations, which are crucial for enhancing the bifunctionality, remains challenging. Herein, PtCo@PtIr nanoparticles are precisely designed and fabricated with a quasi-octahedral PtCo nanocrystal as a highly atomically ordered core and an ultrathin PtIr atomic layer as a compressively strained shell. Owing to their geometric and core-shell features, the PtCo@PtIr nanoparticles deliver approximately six and eight times higher mass and specific activities, respectively, as an ORR catalyst than a commercial Pt/C catalyst. The half-wave potential of PtCo@PtIr exhibits a negligible decrease by 9 mV after 10 000 cycles, indicating extraordinary ORR durability because of the ordered arrangement of Pt and Co atoms. When evaluated using the ORR-OER dual reaction upon the introduction of Ir, PtCo@PtIr exhibits a small ORR-OER overpotential gap of 679 mV, demonstrating its great potential as a bifunctional electrocatalyst for fabricating fuel cells. The findings pave the way for designing precise intermetallic core-shell nanocrystals as highly functional catalysts.
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Anaerobic digestion is an environmentally friendly method for reclaiming waste activated sludge. However, it cannot be overlooked that the solid residue generated from this process can still pose environmental risks and impose economic pressure on society. To mitigate and recycle the solid residue, this study utilized it as a primary raw material for manufacturing ceramsite with potential applications in wastewater treatment. The optimal ratio of solid residue to fly ash was demonstrated to be 6:4 with an additional 15% of clay supplementing the raw ceramsite materials. Furthermore, the optimal sintering process was established as preheating at 300 °C for 25 min followed by sintering at 1085 °C for 10 min, as determined through an L16 (44) Orthogonal test. The prepared ceramsite demonstrated advantageous performance parameters that exceeded the standards outlined in the Chinese industry standard CJ/T 299-2008 for water treatment artificial ceramsite. When utilized in an ozonation system, the ceramsite exhibited remarkable catalytic activity for phenol degradation by promoting the decomposition of molecular O3 into hydroxyl radicals. Additionally, it displayed minimal leaching of heavy metals and lower application costs. These findings emphasize its attractiveness in water and wastewater treatment processes and present a practical strategy for reclaiming this solid residue.
Subject(s)
Complex Mixtures , Metals, Heavy , Ozone , Sewage , Anaerobiosis , Metals, Heavy/analysis , Coal Ash , Solid WasteABSTRACT
The upregulation of vascular endothelial growth factor (VEGF) is strongly associated with the development of choroidal neovascularization (CNV) in patients with neovascular age-related macular degeneration (nAMD). Currently, the standard treatment for nAMD involves frequent intravitreal injections of anti-VEGF agents, which inhibit the growth of new blood vessels and prevent leakage. However, this treatment regimen places a significant burden on patients, their families, and healthcare providers due to the need for repeated visits to the clinic for injections. Gene therapy, which enables the sustained expression of anti-VEGF proteins after a single injection, can dramatically reduce the treatment burden. KH631 is a recombinant adeno-associated virus 8 vector that encodes a human VEGF receptor fusion protein, and it is being developed as a long-term treatment for nAMD. In preclinical studies using non-human primates, subretinal administration of KH631 at a low dose of 3 × 108 vg/eye resulted in remarkable retention of the transgene product in the retina and prevented the formation and progression of grade IV CNV lesions. Furthermore, sustained transgene expression was observed for more than 96 weeks. These findings suggest that a single subretinal injection of KH631 has the potential to offer a one-time, low-dose treatment for nAMD patients.
Subject(s)
Choroidal Neovascularization , Macular Degeneration , Animals , Humans , Vascular Endothelial Growth Factor A/metabolism , Retina/metabolism , Choroidal Neovascularization/genetics , Choroidal Neovascularization/therapy , Primates/genetics , Primates/metabolism , Intravitreal Injections , RNA , Macular Degeneration/pathology , Genetic Therapy/methods , Angiogenesis Inhibitors/pharmacology , Recombinant Fusion ProteinsABSTRACT
OBJECTIVES: CT and MR are often needed to determine the location and extent of brain lesions collectively to improve diagnosis. However, patients with acute brain diseases cannot complete the MRI examination within a short time. The aim of the study is to devise a cross-device and cross-modal medical image synthesis (MIS) method Cross2SynNet for synthesizing routine brain MRI sequences of T1WI, T2WI, FLAIR, and DWI from CT with stroke and brain tumors. MATERIALS AND METHODS: For the retrospective study, the participants covered four different diseases of cerebral ischemic stroke (CIS-cohort), cerebral hemorrhage (CH-cohort), meningioma (M-cohort), glioma (G-cohort). The MIS model Cross2SynNet was established on the basic architecture of conditional generative adversarial network (CGAN), of which, the fully convolutional Transformer (FCT) module was adopted into generator to capture the short- and long-range dependencies between healthy and pathological tissues, and the edge loss function was to minimize the difference in gradient magnitude between synthetic image and ground truth. Three metrics of mean square error (MSE), peak signal-to-noise ratio (PSNR), and structure similarity index measure (SSIM) were used for evaluation. RESULTS: A total of 230 participants (mean patient age, 59.77 years ± 13.63 [standard deviation]; 163 men [71%] and 67 women [29%]) were included, including CIS-cohort (95 participants between Dec 2019 and Feb 2022), CH-cohort (69 participants between Jan 2020 and Dec 2021), M-cohort (40 participants between Sep 2018 and Dec 2021), and G-cohort (26 participants between Sep 2019 and Dec 2021). The Cross2SynNet achieved averaged values of MSE = 0.008, PSNR = 21.728, and SSIM = 0.758 when synthesizing MRIs from CT, outperforming the CycleGAN, pix2pix, RegGAN, Pix2PixHD, and ResViT. The Cross2SynNet could synthesize the brain lesion on pseudo DWI even if the CT image did not exhibit clear signal in the acute ischemic stroke patients. CONCLUSIONS: Cross2SynNet could achieve routine brain MRI synthesis of T1WI, T2WI, FLAIR, and DWI from CT with promising performance given the brain lesion of stroke and brain tumor.
Subject(s)
Brain Neoplasms , Ischemic Stroke , Stroke , Male , Humans , Female , Middle Aged , Retrospective Studies , Magnetic Resonance Imaging , Stroke/diagnostic imaging , Brain/diagnostic imaging , Brain Neoplasms/diagnostic imaging , Tomography, X-Ray Computed , Image Processing, Computer-AssistedABSTRACT
OBJECTIVE: To establish a multi-dimensional representation solely on structural MRI (sMRI) for early diagnosis of AD. METHODS: A total of 3377 participants' sMRI from four independent databases were retrospectively identified to construct an interpretable deep learning model that integrated multi-dimensional representations of AD solely on sMRI (called s2MRI-ADNet) by a dual-channel learning strategy of gray matter volume (GMV) from Euclidean space and the regional radiomics similarity network (R2SN) from graph space. Specifically, the GMV feature map learning channel (called GMV-Channel) was to take into consideration spatial information of both long-range spatial relations and detailed localization information, while the node feature and connectivity strength learning channel (called NFCS-Channel) was to characterize the graph-structured R2SN network by a separable learning strategy. RESULTS: The s2MRI-ADNet achieved a superior classification accuracy of 92.1% and 91.4% under intra-database and inter-database cross-validation. The GMV-Channel and NFCS-Channel captured complementary group-discriminative brain regions, revealing a complementary interpretation of the multi-dimensional representation of brain structure in Euclidean and graph spaces respectively. Besides, the generalizable and reproducible interpretation of the multi-dimensional representation in capturing complementary group-discriminative brain regions revealed a significant correlation between the four independent databases (p < 0.05). Significant associations (p < 0.05) between attention scores and brain abnormality, between classification scores and clinical measure of cognitive ability, CSF biomarker, metabolism, and genetic risk score also provided solid neurobiological interpretation. CONCLUSION: The s2MRI-ADNet solely on sMRI could leverage the complementary multi-dimensional representations of AD in Euclidean and graph spaces, and achieved superior performance in the early diagnosis of AD, facilitating its potential in both clinical translation and popularization.
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BACKGROUND: Lagophthalmos, a common complication after blepharoptosis correction, has plagued oculoplastic surgeons. The goal of this study was to investigate the effect of tape eyelid closure on reducing the occurrence of lagophthalmos after blepharoptosis correction. METHODS: From April 2020 to June 2021, a total of 112 patients with severe congenital ptosis received corrective surgery at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University. Of these, 48 underwent frontalis muscle advancement technique and 64 underwent conjoint fascial sheath suspension. Preoperative data collected included demographics, levator function, Bell's phenomenon, and marginal reflex distance 1 (MRD1). Postoperative data included surgery type, MRD1, eyelid closure function, aesthetic outcomes (including eyelid contour, eyelid symmetry, and eyelid crease), keratitis, and other complications. RESULTS: Frontalis muscle advancement technique group: the median of safe eye closure time was 7.3 months (positive Bell's phenomenon; interquartile range [IQR], 3.8-10.8 months) and 13.9 months (poor Bell's phenomenon; IQR, 11.6-16.1 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.52 ± 0.82 vs 3.85 ± 0.58 mm, P < 0.05). Conjoint fascial sheath suspension group: the median of safe eye closure time was 5.7 months (positive Bell's phenomenon; IQR, 2.9-8.5 months) and 12.4 months (poor Bell's phenomenon; IQR, 8.1-16.7 months). There was a significant improvement between the preoperative and postoperative MRD1 (-1.02 ± 0.91 vs 4.15 ± 1.03 mm, P < 0.05). All patients/guardians were satisfied with the aesthetic outcomes. CONCLUSIONS: Tape tarsorrhaphy is a safe, easy-to-learn method for treating lagophthalmos with a good aesthetic outcome.
Subject(s)
Blepharoplasty , Blepharoptosis , Lagophthalmos , Humans , Blepharoptosis/surgery , Blepharoptosis/congenital , Oculomotor Muscles/surgery , Eyelids/surgery , Blepharoplasty/methods , Retrospective Studies , Treatment OutcomeABSTRACT
BACKGROUND: Severe congenital ptosis is a common ocular deformity in pediatric patients that can significantly impact visual development and aesthetic appearance, leading to negative psychosocial outcomes. The frontalis muscle advancement technique is a well-established surgical treatment for severe congenital ptosis. Aesthetic changes of the brow-eye continuum often plays an important role in ptosis surgery. METHODS: We conducted a single-center retrospective case series study of patients with severe congenital ptosis who underwent the frontalis muscle advancement technique at the Department of Plastic and Reconstructive Surgery, Xijing Hospital, Fourth Military Medical University between April 2020 and June 2021. The study aimed to evaluate the aesthetic changes of the eyebrow-eyelid continuum after surgery. The main outcome measurements included marginal reflex distance 1, palpebral fissure height, eyebrow position, upper eyelid to lower eyebrow distance, lower eyelid to upper eyebrow distance, and nasal base to lower eyelid distance. RESULTS: The study included 48 patients (66 eyelids), with 30 unilateral and 18 bilateral patients. Our analysis found that eyebrow height decreased by an average of 4.8% postoperatively relative to preoperatively in all patients. CONCLUSIONS: The frontalis muscle advancement technique has demonstrated effectiveness in achieving aesthetically pleasing outcomes in children with severe ptosis. It is crucial to pay careful attention to the brow-eye continuum during the correction process, as its harmony can greatly impact the final result.
Subject(s)
Blepharoplasty , Blepharoptosis , Humans , Child , Blepharoplasty/methods , Retrospective Studies , Blepharoptosis/surgery , Blepharoptosis/congenital , Esthetics , Muscles/surgery , Oculomotor Muscles/surgeryABSTRACT
Despite their limitations, epidemiological studies provide information useful for formulating effective and efficient injury prevention strategies. The aim is to carry out an epidemiology study of maxillofacial fracture in Xijing Hospital. Level of Evidence: Level II-therapeutic study.
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BACKGROUND: The superomedial pedicle reduction mammoplasty has gained popularity and is an important alternative approach for reduction mammoplasty, while the inferior pedicle reduction mammaplasty remains by far the most performed as it is considered to provide the best vascularization to the nipple-areola complex, allowing safe removal of large amount of redundant tissue. The authors conducted the first systematic review and meta-analysis in an attempt to declare the differences of the superomedial pedicle versus the inferior pedicle reduction technique by comparing the postoperative complications. METHODS: PubMed, MEDLINE, and Cochrane Library for clinical studies were queried from inception to January 1, 2024. Review Manager Version 5.4 was used for this meta-analysis. A random effects model was applied to OR, and 95%CI were determined using the Mantel-Haenszel method. The I2 test was used to assess heterogeneity, and the Newcastle-Ottawa scale was used to assess the risk of bias in the nonrandomized studies. RESULTS: Twelve observational comparative studies were included. The superomedial pedicle technique had a statistically lower rate of overall complications (OR 0.59, 95% CI 0.47-0.75; p < 0.0001) and delayed wound healing (OR 0.46, 95% CI 0.33-0.64; p < 0.00001) than the inferior pedicle technique. No significant differences in wound dehiscence, infection, seroma, hematoma, skin necrosis, fat necrosis, NAC necrosis, nipple sensation decrease or loss, asymmetry, hypertrophic scarring, and reoperation were noted. CONCLUSIONS: Both two techniques are equally safe and reliable, while the superomedial pedicle technique resulted in a statistically lower rate of overall complications and delayed wound healing. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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BACKGROUND: Poor Bell's phenomenon is often considered a relative contraindication for ptosis surgery, as it increases the risk of corneal exposure and dry eye symptoms after surgery. However, the Bell's phenomenon may vary in different individuals and sleep stages, making it inaccurate to predict the position of the eye during sleep based on awake examination. This study aimed to investigate the role of Bell's phenomenon in ptosis surgery and the management of nocturnal lagophthalmos. METHODS: We conducted a retrospective case series of 23 patients with ptosis and poor Bell's phenomenon who underwent different surgical techniques at Xijing Hospital from April 2020 to June 2021. We assessed Bell's phenomenon at different stages of sleep and collected data on ptosis degree, surgical approach, lagophthalmos, complications, and outcomes. RESULTS: Of the total 23 patients originally considered for study, 9 with frontalis muscle advancement technique, 8 with conjoint fascial sheath suspension, 4 with levator resection technique, and 2 with levator aponeurosis plication technique. All patients achieved satisfactory correction of ptosis. One patient had prolonged lagophthalmos and underwent reoperation to lower the eyelid height. Other complications were minor and resolved with conservative treatment. CONCLUSION: We conclude that poor Bell's phenomenon is not a relative contraindication for ptosis surgery. Nocturnal lagophthalmos should be monitored after ptosis surgery regardless of the Bell's phenomenon results. Tape eyelid closure can be an effective solution to protect the corneal surface during nocturnal lagophthalmos. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to Table of Contents or the online Instructions to Authors www.springer.com/00266 .
Subject(s)
Blepharoplasty , Blepharoptosis , Lagophthalmos , Humans , Retrospective Studies , Oculomotor Muscles/surgery , Blepharoptosis/surgery , Blepharoplasty/methods , Eyelids/surgeryABSTRACT
This meta-analysis aims to comprehensively assess the impact of laparoscopic radical prostatectomy (LRP) on wound infection in patients with prostate cancer (PCa). A systematic search was conducted, from database inception to November 2023, in EMBASE, Google Scholar, Cochrane Library, PubMed, Wanfang and China National Knowledge Infrastructure databases for randomized controlled trials (RCTs) comparing LRP with open radical prostatectomy (ORP) in the treatment of PCa. Two researchers independently screened the literature, extracted data and conducted quality assessments based on pre-defined inclusion and exclusion criteria. Stata 17.0 software was employed for data analysis. Overall, 15 RCTs involving 1458 PCa patients were included. The analysis revealed the incidence of wound infection (odds ratio [OR] = 0.28, 95% confidence interval [CI] = 0.16-0.51, p < 0.001) and complications (OR = 0.27, 95% CI = 0.20-0.37, p < 0.001) was significantly lower in the LRP group compared to the ORP group. This study demonstrates that LRP in PCa patients can effectively reduce the incidence of wound infections and complications, indicating significant therapeutic efficacy and justifying its broader clinical application.
Subject(s)
Laparoscopy , Prostatectomy , Prostatic Neoplasms , Surgical Wound Infection , Humans , Male , Prostatectomy/methods , Prostatectomy/adverse effects , Prostatic Neoplasms/surgery , Laparoscopy/methods , Laparoscopy/adverse effects , Surgical Wound Infection/prevention & control , Surgical Wound Infection/epidemiology , Surgical Wound Infection/etiology , Middle Aged , Aged , Randomized Controlled Trials as TopicABSTRACT
Purpose: To investigate the pharmacokinetics and tissue distribution of VGB racemate and its single enantiomers, and explore the potential of clinic development for single enantiomer S-VGB. Methods: In the pharmacokinetics study, male Sprague-Dawley rats were gavaged with VGB racemate or its single enantiomers dosing 50, 100 or 200 mg/kg, and the blood samples were collected during 12 h at regular intervals. In the experiment of tissue distribution, VGB and its single enantiomers were administered intravenously dosing 200 mg/kg, and the tissues including heart, liver, spleen, lung and kidney, eyes, hippocampus, and prefrontal cortex were separated at different times. The concentrations of R-VGB and S-VGB in the plasma and tissues were measured using HPLC. Results: Both S-VGB and R-VGB could be detected in the plasma of rats administered with VGB racemate, reaching Cmax at approximately 0.5 h with t1/2 2-3 h. There was no significant pharmacokinetic difference between the two enantiomers when VGB racemate was given 200 mg/kg and 100 mg/kg. However, when given at the dose of 50 mg/kg, S-VGB presented a shorter t1/2 and a higher Cl/F than R-VGB, indicating a faster metabolism of S-VGB. Furthermore, when single enantiomer was administered respectively, S-VGB presented a slower metabolism than R-VGB, as indicated by a longer t1/2 and MRT but a lower Cmax. Moreover, compared with the VGB racemate, the single enantiomers S-VGB and R-VGB had shorter t1/2 and MRT, higher Cmax and AUC/D, and lower Vz/F and Cl/F, indicating the stronger oral absorption and faster metabolism of single enantiomer. In addition, regardless of VGB racemate administration or single enantiomer administration, S-VGB and R-VGB had similar characteristics in tissue distribution, and the content of S-VGB in hippocampus, prefrontal cortex and liver was much higher than that of R-VGB. Conclusions: Although there is no transformation between S-VGB and R-VGB in vivo, those two enantiomers display certain disparities in the pharmacokinetics and tissue distribution, and interact with each other. These findings might be a possible interpretation for the pharmacological and toxic effects of VGB and a potential direction for the development and optimization of the single enantiomer S-VGB.
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Achieving electronic/steric control and realizing selectivity regulation in nanocatalysis remains a formidable challenge, as the dynamic nature of metal-ligand interfaces, including dissolution (metal leaching) and structural reconstruction, poses significant obstacles. Herein, we disclose carboranyls (CBs) as unprecedented carbon-bonded functional ligands (Eads.CB-Au(111)=-2.90â eV) for gold nanoparticles (AuNPs), showcasing their exceptional stabilization capability that is attributed by strong Au-C bonds combined with B-Hâ â â Au interactions. The synthesized CB@AuNPs exhibit core(Aun)-satellite(CB2Au-) structure, showing high stability towards multiple stimuli (110 °C, pH=1-12, thiol etchants). In addition, different from conventional AuNP catalysts such as triphenylphosphine (PPh3) stabilized AuNPs, dissolution of catalytically active gold species was suppressed in CB@AuNPs under the reaction conditions. Leveraging these distinct features, CB@AuNPs realized outstanding p : o selectivities in aromatic bromination. Unbiased arenes including chlorobenzene (up to >30 : 1), bromobenzene (15 : 1) and phenyl acrylate were examined using CB@AuNPs as catalysts to afford highly-selective p-products. Both carboranyl ligands and carboranyl derived counterions are crucial for such regioselective transformation. This work has provided valuable insights for AuNPs in realizing diverse regioselective transformations.
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Tetrazole is widely utilized as a bioisostere for carboxylic acid in the field of medicinal chemistry and drug development, enhancing the drug-like characteristics of various molecules. Typically, tetrazoles are introduced from their nitrile precursors through late-stage functionalization. In this work, we propose a novel strategy involving the use of diversely protected, unprecedented tetrazole aldehydes as building blocks. This approach facilitates the incorporation of the tetrazole group into multicomponent reactions or other chemistries, aiding in the creation of a variety of complex, drug-like molecules. These innovative tetrazole building blocks are efficiently and directly synthesized using a Passerini three-component reaction (PT-3CR), employing cost-effective and readily available materials. We further showcase the versatility of these new tetrazole building blocks by integrating the tetrazole moiety into various multicomponent reactions (MCRs), which are already significantly employed in drug discovery. This technique represents a unique and complementary method to existing tetrazole synthesis processes. It aims to meet the growing demand for tetrazole-based compound libraries and novel scaffolds, which are challenging to synthesize through other methods.
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Conventional hydrogels such as polyacrylamide and polyacrylic acid ones seldom exhibit phosphorescences at ambient conditions, which limit their applications as optical materials. We propose and demonstrate here a facile strategy to afford these hydrogels with room-temperature phosphorescence by polymerization-induced crystallization of dopant molecules that results in segregation and confinement of the gel matrix with carbonyl groups and thus clusterization-induced phosphorescence. As a model system, crown ethers (CEs) are dissolved in an aqueous solution of concentrated acrylamide that greatly increases the solubility of CEs. During the polymerization process, CEs crystallize to form large spherulites in the polyacrylamide hydrogel. The crystallization arises from the drastically reduced solubility of CEs after the conversion of monomers to polymers during the gel synthesis. The resultant composite hydrogel with a water content of 67 wt % exhibits extraordinary phosphorescence behavior yet maintains good stretchability and resilience. We found that the partial gel matrix is squeezed and confined by in situ-formed crystals, leading to carbonyl clusters and thus phosphorescence emission. The composite gel shows green phosphorescence with an emission peak at 512 nm and a lifetime of 342 ms. The afterglow emission is detectable by the naked eye for several seconds. This strategy has good universality, as validated in other hydrogels with different polymeric matrices and dopant molecules. The development of hydrogels with good mechanical and phosphorescent properties should merit the design of multifunctional soft machines with applications in biomedical and engineering fields.