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1.
J Org Chem ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632865

RESUMO

The photochemistry of noncovalent interactions to promote organic transformations is an emerging approach to providing fresh opportunities in synthetic chemistry. Generally, the external substance is necessary to add as an interaction partner, thereby sacrificing the atom economy of the reaction. Herein, we describe a catalyst-free and noncovalent interaction-mediated strategy to access the olefination of N-tosylhydrazones using acetone as a solvent and an interaction partner. This protocol also features broad substrate scope, excellent functional group compatibility, and mild reaction conditions without transition metals. Moreover, the gram-scale synthesis of olefins and the generation of pharmaceutical intermediates highlighted its practical applicability. Lastly, mechanistic studies indicate that the reaction was initiated via noncovalent interactions between acetone and N-tosylhydrazone anion, which is also supported by density functional theory calculations.

2.
Cell Stem Cell ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38631356

RESUMO

Understanding cellular coordination remains a challenge despite knowledge of individual pathways. The RNA exosome, targeting a wide range of RNA substrates, is often downregulated in cellular senescence. Utilizing an auxin-inducible system, we observed that RNA exosome depletion in embryonic stem cells significantly affects the transcriptome and proteome, causing pluripotency loss and pre-senescence onset. Mechanistically, exosome depletion triggers acute nuclear RNA aggregation, disrupting nuclear RNA-protein equilibrium. This disturbance limits nuclear protein availability and hinders polymerase initiation and engagement, reducing gene transcription. Concurrently, it promptly disrupts nucleolar transcription, ribosomal processes, and nuclear exporting, resulting in a translational shutdown. Prolonged exosome depletion induces nuclear structural changes resembling senescent cells, including aberrant chromatin compaction, chromocenter disassembly, and intensified heterochromatic foci. These effects suggest that the dynamic turnover of nuclear RNA orchestrates crosstalk between essential processes to optimize cellular function. Disruptions in nuclear RNA homeostasis result in systemic functional decline, altering the cell state and promoting senescence.

3.
Anal Chem ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634427

RESUMO

The identification of a specific tumor cell is crucial for the early diagnosis and treatment of cancer. However, it remains a challenge due to the limited sensitivity and accuracy, long response time, and low contrast of the recent approaches. In this study, we develop a dual miRNA-triggered DNA walker (DMTDW) assisted by APE1 for the specific recognition of tumor cells. miR-10b and miR-155 were selected as the research models. Without miR-10b and miR-155 presence, the DNA walker remains inactive as its walking strand of W is locked by L1 and L2. After miR-10b and miR-155 are input, the DNA walker is triggered as miR-10b and miR-155 bind to L1 and L2 of W-L1-L2, respectively, unlocking W. The DNA walker is driven by endogenous APE1 that is highly catalytic and is highly expressed in the cytoplasm of tumor cells but barely expressed in normal cells, ensuring high contrast and reaction efficiency for specific recognition of tumor cells. Dual miRNA input is required to trigger the DNA walker, making this strategy with a high accuracy. The DMTDW strategy exhibited high sensitivity for miRNA analysis with a detection limit of 44.05 pM. Living cell-imaging experiments confirmed that the DMTDW could effectively respond to the fluctuation of miRNA and specifically identified MDA-MB-231 cells from different cell lines. The proposed DMTDW is sensitive, rapid, and accurate for specific tumor cell recognition. We believe that the DMTDW strategy can become a powerful diagnostic tool for the specific recognition of tumor cells.

4.
Sci Rep ; 14(1): 8203, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589529

RESUMO

The neural network method is a type of machine learning that has made significant advances over the past few years in a variety of fields, particularly text, speech, images, videos, etc. In areas where data is unstructured, traditional machine learning has not been able to surpass the 'glass ceiling'; therefore, researchers have turned to neural networks as auxiliary tools to achieve significant breakthroughs or develop new research methods. An array of computational chemistry challenges can be addressed using neural networks, including virtual screening, quantitative structure-activity relationships, protein structure prediction, materials design, quantum chemistry, and property prediction, among others. This paper proposes a strategy for predicting the chemical properties of fruits by using graph neural networks, and it aims to provide some guidance to researchers and streamline the identification process.


Assuntos
Frutas , Redes Neurais de Computação , Aprendizado de Máquina , Relação Quantitativa Estrutura-Atividade
5.
Heliyon ; 10(7): e28465, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596109

RESUMO

Background: Grade IV circular hemorrhoids are difficult to treat. We aim to describe the modified whitehead hemorrhoidectomy procedure and to assess the effectiveness and safety of this procedure for grade IV circular hemorrhoid patients. Methods: Patients with grade Ⅳ circular hemorrhoids who underwent modified Whitehead hemorrhoidectomy and partial hemorrhoidectomy for fourth-degree circular mixed hemorrhoids were retrospectively reviewed. Clinical data were extracted from the database at our institution, and long-term postoperative complications were assessed through repeated outpatient examinations and telephonic communication. Results: A total of 205 patients were included in this study. The mean operative time was 59.2 ± 13.8 min. The average hospital stay was 4.6 ± 1.0 days. For postoperative complications, 66 (32.2%) patients had urinary retention, 10 (4.9%) patients had a sense of incomplete rectal emptying, 5 (2.4%) patients had anal incontinence, and 6 (2.9%) patients had wound infection. For long-term postoperative complications, 3 (1.5%) patients experienced mild to moderate anal stricture, 2 (1%) patients experienced mucosal ectropion, they all had smooth recoveries, and none of them needed secondary surgery. None of these patients had a hemorrhoid recurrence. A total of 205 patients who received modified Whitehead hemorrhoidectomy and 161 who received partial hemorrhoidectomy were included. There were no residual hemorrhoids in patients who received modified Whitehead hemorrhoidectomy, and none had hemorrhoid recurrence. Fifty-eight patients who received partial hemorrhoidectomy had hemorrhoidal residues, and 19 patients experienced hemorrhoid recurrence. After modified Whitehead hemorrhoidectomy, 3 patients developed anal stenosis, and 2 had mucosal ectropion. Four patients developed anal stricture after partial hemorrhoidectomy, and none had mucosal ectropion. They all had smooth recoveries, and none of them needed a secondary surgery. For the mean duration of surgery, postoperative bleeding, postoperative pain, wound infection, sense of incomplete rectal emptying, anal incontinence, and urinary retention, no statistically significant differences were found between the two groups. Conclusions: Compared with partial hemorrhoidectomy, modified whitehead hemorrhoidectomy is an effective and safe surgical procedure and does not significantly increase the risk of anal stenosis and mucosal ectropion for grade IV circular hemorrhoid patients. Prospective randomized controlled trials are needed to verify our results.

6.
J Chromatogr A ; 1722: 464864, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38598890

RESUMO

In this study, a novel piperidinium-sulfonate based zwitterionic hydrophilic monolith was prepared through thermally initiated co-polymerization of a piperidinium-sulfonate monomer 3-(4-((methacryloyloxy)methyl)-1-methylpiperidin-1-ium-1-yl)propane-1-sulfonate (MAMMPS), and a hydrophilic crosslinker N,N'-methylenebisacrylamide (MBA) using n-propanol and H2O as porogenic system. Satisfactory mechanical and chemical stabilities, good repeatability and high column efficiency (120,000 N/m) were obtained on the optimal monolith. The resulting poly(MAMMPS-co-MBA) monolith showed a typical HILIC retention behavior over an ACN content range between 5 and 95 %. Furthermore, this column exhibited good separation performance for various polar compounds. Compared to quaternary ammonium-sulfonate based zwitterionic hydrophilic monolith, i.e. poly(N,N-dimethyl-N-methacryloxyethyl-N-(3-sulfopropyl)ammonium betaine-co-MBA), the poly(MAMMPS-co-MBA) monolith displayed stronger retention and better selectivity for the tested phenolic and amine compounds at different pH conditions. Finally, this column was applied for the separation of six sulfonamide antibiotics, and the analytical characteristics of the method were evaluated in terms of precision, repeatability, limits of detection (LOD) and quantitation (LOQ). Overall, this study not only developed a novel HILIC monolithic column, but also proved the potential of piperidinium-sulfonate based zwitterionic chemistry as stationary phase, which further increased the structure diversity of zwitterionic HILIC stationary phases.

7.
Artigo em Inglês | MEDLINE | ID: mdl-38597996

RESUMO

We have previously identified a latent interaction mechanism between non-small cell lung cancer cells (NSCLCC) and their associated macrophages (TAM) mediated by mutual paracrine activation of the HMGB1/RAGE/NF-κB signaling. Activation of this mechanism results in TAM stimulation and PD-L1 upregulation in the NSCLCC. In the present work, we found that free DOX at a low concentration that does not cause DNA damage could activate the HMGB1/RAGE/NF-κB/PD-L1 pathway byinducing oxidative stress. It was thus proposed that a combination of low-dose DOX and a PD-L1 blocker delivered in the NSCLC tumor would achieve synergistic TAM stimulation and thereby synergetic anti-tumor potency. To prove this idea, DOX and BMS-202 (a PD-L1 blocker) were loaded to black phosphorus (BP) nanoparticles after dosage titration to yield the BMS-202/DOX@BP composites that rapidly disintegrated and released drug cargo upon mild photothermal heating at 40 °C. In vitro experiments then demonstrated that low-dose DOX and BMS-202 delivered via BMS-202/DOX@BP under mild photothermia displayed enhanced tumor cell toxicity with a potent synergism only in the presence of TAM. This enhanced synergism was due to an anti-tumor M1-like TAM phenotype that was synergistically induced by low dose DOX plus BMS-202 only in the presence of the tumor cells, indicating the damaged tumor cells to be the cardinal contributor to the M1-like TAM stimulation. In vivo, BMS-202/DOX@BP under mild photothermia exhibited targeted delivery to NSCLC graft tumors in mice and synergistic anti-tumor efficacy of delivered DOX and BMS-202. In conclusion, low-dose DOX in combination with a PD-L1 blocker is an effective strategy to turn TAM against their host tumor cells exploiting the HMGB1/RAGE/NF-κB/PD-L1 pathway. The synergetic actions involved highlight the value of TAM and the significance of modulating tumor cell-TAM cross-talk in tumor therapy. Photothermia-responsive BP provides an efficient platform to translate this strategy into targeted, efficacious tumor therapy.

8.
Pediatr Nephrol ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38589698

RESUMO

BACKGROUND: Lowe syndrome is characterized by the presence of congenital cataracts, psychomotor retardation, and dysfunctional proximal renal tubules. This study presents a case of an atypical phenotype, investigates the genetic characteristics of eight children diagnosed with Lowe syndrome in southern China, and performs functional analysis of the novel variants. METHODS: Whole-exome sequencing was conducted on eight individuals diagnosed with Lowe syndrome from three medical institutions in southern China. Retrospective collection and analysis of clinical and genetic data were performed, and functional analysis was conducted on the five novel variants. RESULTS: In our cohort, the clinical symptoms of the eight Lowe syndrome individuals varied. One patient was diagnosed with Lowe syndrome but did not present with congenital cataracts. Common features among all patients included cognitive impairment, short stature, and low molecular weight proteinuria. Eight variations in the OCRL gene were identified, encompassing three previously reported and five novel variations. Among the novel variations, three nonsense mutations were determined to be pathogenic, and two patients harboring novel missense variations of uncertain significance exhibited severe typical phenotypes. Furthermore, all novel variants were associated with altered protein expression levels and impacted primary cilia formation. CONCLUSION: This study describes the first case of an atypical Lowe syndrome patient without congenital cataracts in China and performs a functional analysis of novel variants in the OCRL gene, thereby expanding the understanding of the clinical manifestations and genetic diversity associated with Lowe syndrome.

9.
Chem Commun (Camb) ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591991

RESUMO

An efficient electrochemical dual C(sp3)-H amination was developed under metal-free and chemical oxidant-free conditions. A series of imidazo[1,5-a]quinazolin-5(4H)-ones and 5-oxo-4,5-dihydroimidazo[1,5-a]quinazoline-3-carbonitriles can be obtained in high yields and the product distribution can be modulated by virtue of this method. The reaction mechanism was investigated and the corresponding intermediates were studied. The reaction features a broad substrate scope, regulation of the product distribution, mild conditions and scalable preparation.

10.
Adv Mater ; : e2314271, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38569202

RESUMO

Transition metal chalcogenides (TMCs) emerge as promising anode materials for sodium-ion batteries (SIBs), heralding a new era of energy storage solutions. Despite their potential, the mechanisms underlying their performance enhancement and susceptibility to failure in ether-based electrolytes remain elusive. This study delves into these aspects, employing CoS2 electrodes as a case in point to elucidate the phenomena. The investigation reveals that CoS2 undergoes a unique irreversible and progressive solid-liquid-solid phase transition from its native state to sodium polysulfides (NaPSs), and ultimately to a Cu1.8S/Co composite, accompanied by a gradual morphological transformation from microspheres to a stable 3D porous architecture. This reconstructed 3D porous structure is pivotal for its exceptional Na+ diffusion kinetics and resilience to cycling-induced stress, being the main reason for ultrastable cycling and ultrahigh rate capability. Nonetheless, the CoS2 electrode suffers from an inevitable cycle life termination due to the microshort-circuit induced by Na metal corrosion and separator degradation. Through a comparative analysis of various TMCs, a predictive framework linking electrode longevity is established to electrode potential and Gibbs free energy. Finally, the cell failure issue is significantly mitigated at a material level (graphene encapsulation) and cell level (polypropylene membrane incorporation) by alleviating the NaPSs shuttling and microshort-circuit.

11.
Molecules ; 29(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611712

RESUMO

Zeolite microspheres have been successfully applied in commercial-scale separators such as oxygen concentrators. However, further enhancement of their applications is hampered by the post-synthetic shaping process that formulates the zeolite powder into packing-sized spherical bodies with various binders leading to active site blockage and suboptimal performance. Herein, binderless zeolite microspheres with a tunable broad size range from 2 µm to 500 µm have been developed with high crystallinity, sphericity over 92%, monodispersity with a coefficient of variation (CV) less than 5%, and hierarchical pore architecture. Combining precursor impregnation and steam-assisted crystallization (SAC), mesoporous silica microspheres with a wide size range could be successfully transformed into zeolite. For preserved size and spherical morphology, a judicious selection of the synthesis conditions is crucial to ensure a pure phase, high crystallinity, and hierarchical architecture. For the sub-2-µm zeolite microsphere, low-temperature prolonged aging was important so as to suppress external zeolization that led to a large, single macroporous crystal. For the large 500 µm sphere, ultrasound pretreatment and vacuum impregnation were crucial and facilitated spatially uniform gel matrix dispersion and homogenous crystallization. The obtained zeolite 5A microspheres exhibited excellent air separation performance, while the 4A microspheres displayed ammonium removal capabilities. This work provides a general strategy to overcome the existing limitations in fabricating binder-free technical bodies of zeolites for various applications.

12.
Front Immunol ; 15: 1368516, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601146

RESUMO

Background: Differences in border zone contribute to different outcomes post-infarction, such as left ventricular aneurysm (LVA) and myocardial infarction (MI). LVA usually forms within 24 h of the onset of MI and may cause heart rupture; however, LVA surgery is best performed 3 months after MI. Few studies have investigated the LVA model, the differences in border zones between LVA and MI, and the mechanism in the border zone. Methods: The LVA, MI, and SHAM mouse models were used. Echocardiography, Masson's trichrome staining, and immunofluorescence staining were performed, and RNA sequencing of the border zone was conducted. The adipocyte-conditioned medium-treated hypoxic macrophage cell line and LVA and MI mouse models were employed to determine the effects of the hub gene, adiponectin (ADPN), on macrophages. Quantitative polymerase chain reaction (qPCR), Western blot analysis, transmission electron microscopy, and chromatin immunoprecipitation (ChIP) assays were conducted to elucidate the mechanism in the border zone. Human subepicardial adipose tissue and blood samples were collected to validate the effects of ADPN. Results: A novel, simple, consistent, and low-cost LVA mouse model was constructed. LVA caused a greater reduction in contractile functions than MI owing to reduced wall thickness and edema in the border zone. ADPN impeded cardiac edema and promoted lymphangiogenesis by increasing macrophage infiltration post-infarction. Adipocyte-derived ADPN promoted M2 polarization and sustained mitochondrial quality via the ADPN/AdipoR2/HMGB1 axis. Mechanistically, ADPN impeded macrophage HMGB1 inflammation and decreased interleukin-6 (IL6) and HMGB1 secretion. The secretion of IL6 and HMGB1 increased ADPN expression via STAT3 and the co-transcription factor, YAP, in adipocytes. Based on ChIP and Dual-Glo luciferase experiments, STAT3 promoted ADPN transcription by binding to its promoter in adipocytes. In vivo, ADPN promoted lymphangiogenesis and decreased myocardial injury after MI. These phenotypes were rescued by macrophage depletion or HMGB1 knockdown in macrophages. Supplying adipocytes overexpressing STAT3 decreased collagen disposition, increased lymphangiogenesis, and impaired myocardial injury. However, these effects were rescued after HMGB1 knockdown in macrophages. Overall, the IL6/ADPN/HMGB1 axis was validated using human subepicardial tissue and blood samples. This axis could serve as an independent factor in overweight MI patients who need coronary artery bypass grafting (CABG) treatment. Conclusion: The IL6/ADPN/HMGB1 loop between adipocytes and macrophages in the border zone contributes to different clinical outcomes post-infarction. Thus, targeting the IL6/ADPN/HMGB1 loop may be a novel therapeutic approach for cardiac lymphatic regulation and reduction of cell senescence post-infarction.


Assuntos
Proteína HMGB1 , Infarto do Miocárdio , Camundongos , Animais , Humanos , Interleucina-6/metabolismo , Adiponectina/genética , Adiponectina/metabolismo , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Retroalimentação , Infarto do Miocárdio/metabolismo , Macrófagos/metabolismo , Adipócitos/metabolismo
13.
J Pharm Anal ; 14(3): 348-370, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38618251

RESUMO

Emerging research suggests a potential association of progression of Alzheimer's disease (AD) with alterations in synaptic currents and mitochondrial dynamics. However, the specific associations between these pathological changes remain unclear. In this study, we utilized Aß42-induced AD rats and primary neural cells as in vivo and in vitro models. The investigations included behavioural tests, brain magnetic resonance imaging (MRI), liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) analysis, Nissl staining, thioflavin-S staining, enzyme-linked immunosorbent assay, Golgi-Cox staining, transmission electron microscopy (TEM), immunofluorescence staining, proteomics, adenosine triphosphate (ATP) detection, mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) assessment, mitochondrial morphology analysis, electrophysiological studies, Western blotting, and molecular docking. The results revealed changes in synaptic currents, mitophagy, and mitochondrial dynamics in the AD models. Remarkably, intervention with Dengzhan Shengmai (DZSM) capsules emerged as a pivotal element in this investigation. Aß42-induced synaptic dysfunction was significantly mitigated by DZSM intervention, which notably amplified the frequency and amplitude of synaptic transmission. The cognitive impairment observed in AD rats was ameliorated and accompanied by robust protection against structural damage in key brain regions, including the hippocampal CA3, primary cingular cortex, prelimbic system, and dysgranular insular cortex. DZSM intervention led to increased IDE levels, augmented long-term potential (LTP) amplitude, and enhanced dendritic spine density and length. Moreover, DZSM intervention led to favourable changes in mitochondrial parameters, including ROS expression, MMP and ATP contents, and mitochondrial morphology. In conclusion, our findings delved into the realm of altered synaptic currents, mitophagy, and mitochondrial dynamics in AD, concurrently highlighting the therapeutic potential of DZSM intervention.

14.
Mater Today Bio ; 26: 101031, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38558772

RESUMO

Developing a self-elastic sponge integrating active and passive hemostatic mechanisms for the effective management of uncontrolled coagulopathic hemorrhage remains a challenge. We here developed a chitosan-based sponge by integrating freeze-drying, chemical decoration of alkyl chains and phosphate groups, and physical loading of thrombin. The sponge exhibited high mechanical strength, self-elasticity, and rapid shape recovery. The sponge facilitated blood cell adhesion, aggregation, and activation through hydrophobic and electrostatic interactions, as well as accelerated blood clotting. The sponge exhibited higher efficacy than commercial gauze and gelatin sponge in managing uncontrolled hemorrhage from heparinized rat tail amputation, liver superficial injury, and liver perforating wound models. In addition, the sponge exhibited favorable biodegradability and biocompatibility. These findings revealed that the developed sponge holds great potential as a novel hemostat for effectively managing uncontrolled coagulopathic hemorrhage from superficial and perforating wounds.

15.
ACS Omega ; 9(12): 14489-14499, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38559975

RESUMO

Endometrial cancer (EC) is a frequently diagnosed gynecologic cancer. Identifying reliable prognostic genes for predicting EC onset is crucial for reducing patient morbidity and mortality. Here, a comprehensive strategy with transcriptomic and proteomic data was performed to measure EC's characteristics. Based on the publicly available RNA-seq data, death-associated protein kinase 3, recombination signal-binding protein for the immunoglobulin kappa J region, and myosin light chain 9 were screened out as potential biomarkers that affect the EC patients' prognosis. A linear model was further constructed by multivariate Cox regression for the prediction of the risk of being malignant. From further integrative analysis, exosomes were found to have a highly enriched role that might participate in EC occurrence. The findings were validated by qRT-polymerase chain reaction (PCR) and western blotting. Collectively, we constructed a prognostic-gene-based model for EC prediction and found that exosomes participate in EC incidents, revealing significantly promising support for the diagnosis of EC.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38564097

RESUMO

BACKGROUND AND OBJECTIVE: GB221 is a recombinant humanized anti-HER2 monoclonal antibody. The purpose of this study was to evaluate the pharmacokinetic, safety, and immunogenicity of GB221 in healthy Chinese adults in comparison to trastuzumab (Herceptin®). METHODS: In this randomized, double-blind, parallel-group phase I clinical trial, 88 subjects were randomized 1:1 to receive a single intravenous infusion (90-100 min) of GB221 or trastuzumab (6 mg/kg). The primary pharmacokinetic parameters-maximum observed serum concentration (Cmax), area under the serum concentration-time curve from zero to the last quantifiable concentration at time t (AUC0-t), and area under the serum concentration-time curve from time zero to infinity (AUC0-∞)-of GB221 and trastuzumab were compared to establish whether the 90% confidence interval (CI) attained the 80-125% bioequivalence standard. Safety and immunogenicity were also evaluated. RESULTS: The GB221 group (n = 43) and the trastuzumab group (n = 44) showed similar pharmacokinetic characteristics. The geometric mean ratios (90% CI) of Cmax, AUC0-t, and AUC0-∞ between the two groups were 107.53% (102.25-113.07%), 108.31% (103.57-113.26%), and 108.34% (103.57-113.33%), respectively. The incidence of treatment-emergent adverse events (TEAEs) was 83.7% (36/43) of the subjects in the GB221 group and 95.5% (42/44) of the subjects in the trastuzumab group. No subjects withdrew from the trial due to TEAEs, and there were no occurrences of serious adverse events. All subjects tested negative for antidrug antibodies (ADA). CONCLUSION: GB221 demonstrated similar pharmacokinetics to trastuzumab and comparable safety and immunogenicity in healthy Chinese adults.

17.
J Hazard Mater ; 470: 134154, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38581871

RESUMO

In this work, a multiplexed colorimetric strategy was initiated for simultaneous and fast visualization of dyes using low-cost and easy-to-prepare indicator papers as sorbents. Response surface methodology (RSM) was employed to model statistically and optimize the process variables for dyes extraction and colorimetric assays. Multiplexed colorimetry was realized by virtue of synchronous color alignments from different dimensions of multiple dyes co-stained colorimetric cards under RSM-optimized conditions, and smartphone-based image analysis was subsequently performed from different modes to double-check the credibility of colorimetric assays. As concept-to-proof trials, simultaneous visualization of dyes in both beverages and simulated dye effluents was experimentally proved with results highly matched to HPLC or spiked amounts at RSM-predicted staining time as short as 50 s ∼3 min, giving LODs as low as 0.97 ± 0.22/0.18 ± 0.08 µg/mL (tartrazine/brilliant blue) for multiplexed colorimetry, which much lower than those obtained by single colorimetry. Since this is the first case to propose such a RSM-guided multiplexed colorimetric concept, it will provide a reference for engineering of other all-in-one devices which can realize synchronous visualization applications within limited experimental steps.

18.
Opt Lett ; 49(8): 2053-2056, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38621074

RESUMO

Plasmonic nanosensors and the dynamic control of light fields are of the utmost significance in the field of micro- and nano-optics. Here, our study successfully demonstrates a plasmonic nanosensor in a compact coupled resonator system and obtains the pressure-induced transparency phenomenon for the first time to our knowledge. The proposed structure consists of a groove and slot cavity coupled in the metal-insulator-metal waveguide, whose mechanical and optical characteristics are investigated in detail using the finite element method. Simulation results show that we construct a quantitative relationship among the resonator deformation quantity, the applied pressure variation, and the resonant wavelength offset by combining the mechanical and optical properties of the proposed system. The physical features contribute to highly efficient plasmonic nanosensors for refractive index and optical pressure sensing with sensitivity of 1800 nm/RIU and 7.4 nm/MPa, respectively. Furthermore, the light waves are coupled to each other in the resonators, which are detuned due to the presence of pressure, resulting in the pressure-induced transparency phenomenon. It is noteworthy to emphasize that, unlike previously published works, our numerical results take structural deformation-induced changes in optical properties into account, making them trustworthy and practical. The proposed structure introduces a novel, to the best of our knowledge, approach for the dynamic control of light fields and has special properties that can be utilized for the realization of various integrated components.

19.
Nat Aging ; 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38622407

RESUMO

Skeletal muscle aging is a key contributor to age-related frailty and sarcopenia with substantial implications for global health. Here we profiled 90,902 single cells and 92,259 single nuclei from 17 donors to map the aging process in the adult human intercostal muscle, identifying cellular changes in each muscle compartment. We found that distinct subsets of muscle stem cells exhibit decreased ribosome biogenesis genes and increased CCL2 expression, causing different aging phenotypes. Our atlas also highlights an expansion of nuclei associated with the neuromuscular junction, which may reflect re-innervation, and outlines how the loss of fast-twitch myofibers is mitigated through regeneration and upregulation of fast-type markers in slow-twitch myofibers with age. Furthermore, we document the function of aging muscle microenvironment in immune cell attraction. Overall, we present a comprehensive human skeletal muscle aging resource ( https://www.muscleageingcellatlas.org/ ) together with an in-house mouse muscle atlas to study common features of muscle aging across species.

20.
PLoS One ; 19(4): e0297912, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38573995

RESUMO

The bulkhead additional thrust during shield tunneling, the force of friction between shield and soil, and the additional grouting pressure can cause additional stress in the surrounding soil, thereby disturbing existing buildings and structures. However, few studies focused on the disturbance situation when the shield tunneling machine approaches the receiving well. If the additional stress and deformation of the receiving well are too excessive, it could result in the collapse of the receiving well. Based on the two-stage method, this study derived the calculation formula of the additional stress and deformation of the receiving well enclosure structure caused by shield tunneling. Taking a shield machine receiving engineering as the context, this study established a numerical simulation model and compared theoretical calculation, the results of numerical simulation model and on-site monitoring data. Finally, the additional stress of the receiving well is analyzed. The research findings demonstrate that the theoretical prediction results, numerical simulation calculation results, and on-site monitoring data exhibit relatively small calculation errors, which validated the applicability of the theoretical prediction formula and numerical simulation model. As the distance between the shield machine and the receiving well decreases, the disturbance to the receiving well increases sharply. When the distance between the cutter head and the receiving well is less than three times the shield length, it is crucial to enhance the deformation monitoring of the receiving well. The primary factors affecting the additional load and deformation of the receiving well enclosure structure are the force of friction between shield and soil and the additional thrust of the cutterhead. The disturbance caused by the additional grouting pressure on the enclosure structure can be ignored.


Assuntos
Engenharia , Equipamentos de Proteção , Simulação por Computador , Fricção , Solo
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