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In this paper, a combination of theoretical modeling, finite element simulation, and experimental methods is employed to investigate the forming mechanism and evolutionary pattern of the stagnant region during mechanical scratching with a diamond wedge tool. The study is structured as follows: Firstly, a theoretical calculation model for the geometric parameters of the stagnant region on the formed groove surface is established based on the contact friction partition mechanism and slip-line field theory. The model indicates that the geometric parameters lB-sg, lV-sg, and ∆lsg of the stagnant region are determined by the length of the stagnant region lp-sg in the plastic flow plane and the transformation parameters. Secondly, the formation process of the stagnant region in mechanical scratching is investigated using an orthogonal cutting simulation model with a negative rake angle tool. The results reveal that the stagnant region is a plastic deformation region formed due to the geometrical characteristics of the negative front surface of the scratching tool and its excessive extrusion, which leads to the formation of adhesive friction within the material. Thirdly, the characteristics of the stagnant region are determined through scratching experiments. Compared to the material in the plastic flow region, the material within the stagnant region exhibits finer and denser microstructures, reduced surface hardening peaks and hardened layer depths, and significantly improved surface roughness. Finally, the evolutionary pattern of the stagnant region under the influence of scratching processing parameters is examined based on the theoretical calculation model of the geometric parameters and the scratching experiment. The findings indicate that as the wedge angle of the scratching tool decreases, the relief angle increases, the absolute value of the rotation angle around the Y-axis decreases, the scratching speed decreases, and the material's plastic adherence improves, the PI/k value decreases, the lp-sg value increases, and consequently, the geometric parameters lB-sg, lV-sg, and ∆lsg of the stagnant region on the formed groove surface also increase. The deviation analysis of the geometric parameters of the stagnant region reveals a consistent trend between the theoretical and experimental values of lV-sg and ∆lsg, with maximum deviations of 15 µm and 4.13%, respectively. This study provides theoretical and experimental evidence for the establishment of the theoretical model of the stagnant region in mechanical scratching, the analysis of its forming mechanism, and the control of the stagnant region geometric parameters on the formed groove surface.
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We present a PPh3/DDQ-mediated regiospecific selective N-functionalization of arylhydrazines with primary benzylic alcohols and aryl carboxylic acids for the synthesis of N1-benzyl arylhydrazines and N2-acyl arylhydrazines, respectively. This metal- and base-free approach features very short reaction times (about 10 min), broad substrate scope, good functional group tolerance, and mild reaction conditions. Furthermore, N1-benzlated products have also been successfully applied to the concise synthesis of N-substituted indoles and anticancer drug MDM2 inhibitor.
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BACKGROUND: The microneedle fractional radiofrequency system (MFRS) is able to rejuvenate facial appearance by heating and coagulating certain depth of skin tissue. OBJECTIVE: To evaluate the safety and efficacy of a novel vacuum-assisted MFRS for facial contour tightening. METHODS: This prospective, randomized, split-face study included 21 patients who underwent three treatments with a vacuum-assisted MFRS at 1-month intervals. Half of the face was treated with the MFRS; the other half was untreated (control). Facial volume changes and wrinkles were objectively measured using a three-dimensional imaging system and VISIA-CR. RESULTS: Volume changes of the treated midface were -0.24 ± 0.75, -0.59 ± 0.92, and -0.55 ± 0.65 mL at 1, 3, 6 months follow-up; however, measurements of the control side were 0.08 ± 0.70, -0.08 ± 0.53, and - 0.10 ± 0.86 mL, indicating significant reductions (p < 0.05). The number of facial wrinkles on the treated side was significantly reduced to 12.44 ± 4.85 at 3 months and sustained at 6 months (11.11 ± 4.100) compared to the control side (14.89 ± 5.26 and 13.22 ± 4.44, respectively; p < 0.05). No long-term side effects occurred. CONCLUSION: The vacuum-assisted MFRS is safe and effective and is recommended for improving facial tightening and reducing wrinkles. This technology is sufficient to ensure the insertion depth, thus helping to improve the treatment accuracy and safety. The MFRS provides sustained effects for at least 6 months.
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We have recently demonstrated that Sox10 -expressing ( Sox10 + ) cells give rise to mainly type-III neuronal taste bud cells that are responsible for sour and salt taste. The two tissue compartments containing Sox10 + cells in the surrounding of taste buds include the connective tissue core of taste papillae and von Ebner's glands (vEGs) that are connected to the trench of circumvallate and foliate papillae. In this study, we used inducible Cre mouse models to map the cell lineages of connective tissue (including stromal and Schwann cells) and vEGs and performed single cell RNA-sequencing of the epithelium of Sox10-Cre/tdT mouse circumvallate/vEG complex. In vivo lineage mapping showed that the distribution of traced cells in circumvallate taste buds was closely linked with that in the vEGs, but not in the connective tissue. Sox10 , but not the known stem cells marker Lgr5 , expression was enriched in the cell clusters of main ducts of vEGs that contained abundant proliferating cells, while Sox10-Cre/tdT expression was enriched in type-III taste bud cells and excretory ductal cells. Moreover, multiple genes encoding pathogen receptors are enriched in the vEG main ducts. Our data indicate that the main duct of vEGs is a source of Sox10 + taste bud progenitors and susceptible to pathogen infections.
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CRISPR/Cas9 methods are a powerful in vivo approach to edit the genome of Drosophila melanogaster. To convert existing Drosophila GAL4 lines to LexA driver lines in a secondary school classroom setting, we applied the CRISPR-based genetic approach to a collection of Gal4 'driver' lines. The integration of the yellow+ coat color marker into homology-assisted CRISPR knock-in (HACK) enabled visual selection of Gal4-to-LexA conversions using brightfield stereo-microscopy available in a broader set of standard classrooms. Here, we report the successful conversion of eleven Gal4 lines with expression in neuropeptide-expressing cells into corresponding, novel LexA drivers. The conversion was confirmed by LexA- and Gal4-specific GFP reporter gene expression. This curriculum was successfully implemented in a summer course running 16 hours/week for seven weeks. The modularity, flexibility, and compactness of this course should enable development of similar classes in secondary schools and undergraduate curricula, to provide opportunities for experience-based science instruction, and university-secondary school collaborations that simultaneously fulfill research needs in the community of science.
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Protein phase separation plays a very important role in many biological processes and is closely related to the occurrence and development of some serious diseases. So far, the fluorescence imaging method and fluorescence correlation spectroscopy (FCS) have been frequently used to study the phase separation behavior of proteins. Due to the wide size distribution of protein condensates in phase separation from nano-scale to micro-scale in solution and living cells, it is difficult for the fluorescence imaging method and conventional FCS to fully reflect the real state of protein phase separation in the solution due to the low spatio-temporal resolution of the conventional fluorescence imaging method and the limited detection area of FCS. Here, we proposed a novel method for studying the protein phase separation process by objective scanning-based fluorescence cross-correlation spectroscopy (Scan-FCCS). In this study, CRDBP proteins were used as a model and respectively fused with fluorescent proteins (EGFP and mCherry). We first compared conventional FCS and Scan-FCS methods for characterizing the CRDBP protein phase separation behaviors and found that the reproducibility of Scan-FCS is significantly improved by the scanning mode. We studied the self-fusion process of mCherry-CRDBP and EGFP-CRDBP and observed that the phase change concentration of CRDBP was 25 nM and the fusion of mCherry-CRDBP and EGFP-CRDBP at 500 nM was completed within 70 min. We studied the effects of salt concentration and molecular crowding agents on the phase separation of CRDBP and found that salt can prevent the self-fusion of CRDBP and molecular crowding agents can improve the self-fusion of CRDBP. Furthermore, we found the recruitment behavior of CRDBP to ß-catenin proteins and studied their recruitment dynamics. Compared to conventional FCS, Scan-FCCS can significantly improve the reproducibility of measurements due to the dramatic increase of detection zone, and more importantly, this method can provide information about self-fusion and recruitment dynamics in protein phase separation.
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Proteínas de Fluorescência Verde , Espectrometria de Fluorescência , Espectrometria de Fluorescência/métodos , Proteínas de Fluorescência Verde/química , Proteínas Luminescentes/química , Proteínas Recombinantes de Fusão/química , Proteína Vermelha Fluorescente , Separação de FasesRESUMO
Increasing immunotherapy response rate and durability can lead to significant improvements in cancer care. To address this challenge, a novel multivalent immune checkpoint therapeutic platform is constructed through site-specific ligation of anti-PD-L1 nanobody (Nb) on ferritin (Ftn) nanocage. Nb-Ftn blocks PD-1/PD-L1 interaction and downregulates PD-L1 levels via endocytosis-induced degradation. In addition, the cage structure of Ftn allows encapsulation of indocyanine green (ICG), an FDA-approved dye. Photothermal treatment with Nb-Ftn@ICG induces immunogenic death of tumor cells, which improves systemic immune response via maturation of dendritic cells and enhanced infiltration of T cells. Moreover, Nb-Ftn encapsulation significantly enhances cellular uptake, tumor accumulation and retention of ICG. In vivo assays showed that this nanoplatform ablates the primary tumor, suppresses abscopal tumors and inhibits tumor metastasis, leading to a prolonged survival rate. This work presents a novel strategy for improving cancer immunotherapy using multivalent nanobody-ferritin conjugates as immunological targeting and enhancing carriers.
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Antígeno B7-H1 , Ferritinas , Imunoterapia , Imunoterapia/métodos , Camundongos , Animais , Ferritinas/imunologia , Antígeno B7-H1/imunologia , Antígeno B7-H1/antagonistas & inibidores , Anticorpos de Domínio Único/imunologia , Anticorpos de Domínio Único/farmacologia , Neoplasias/terapia , Neoplasias/imunologia , Modelos Animais de Doenças , Verde de Indocianina , Humanos , Linhagem Celular TumoralRESUMO
We report herein the first examples of electrochemical radical retro-allylation of homoallylic alcohols via the cleavage of the C(sp3)-C(sp3) bond. In this reaction, a variety of sulfonyl hydrazides were employed as the environmentally friendly radical sources via an electrochemical dehydrazination with the release of N2 and H2 as the byproducts, leading to sulfonyl allylic compounds in moderate to good yields. The reaction features metal- and base-free reaction conditions, broad functional group tolerance, and a broad substrate scope.
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Enzymes are considered safe and effective therapeutic tools for various diseases. With the increasing integration of biomedicine and nanotechnology, artificial nanozymes offer advanced controllability and functionality in medical design. However, several notable gaps, such as catalytic diversity, specificity and biosafety, still exist between nanozymes and their native counterparts. Here we report a non-metal single-selenium (Se)-atom nanozyme (SeSAE), which exhibits potent nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-mimetic activity. This novel single atom nanozyme provides a safe alternative to conventional metal-based catalysts and effectively cuts off the cellular energy and reduction equivalents through its distinctive catalytic function in tumors. In this study, we have demonstrated the substantial efficacy of SeSAE as an antitumor nanomedicine across diverse mouse models without discernible systemic adverse effects. The mechanism of the NADPH oxidase-like activity of the non-metal SeSAE was rationalized by density functional theory calculations. Furthermore, comprehensive elucidation of the biological functions, cell death pathways, and metabolic remodeling effects of the nanozyme was conducted, aiming to provide valuable insights into the development of single atom nanozymes with clinical translation potential.
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Nanotecnologia , Neoplasias , Animais , Camundongos , Metais , Catálise , Neoplasias/tratamento farmacológico , NanomedicinaRESUMO
BACKGROUND: The excellent efficacy is mitigated by the limited safety profile of microfocused ultrasound procedures. OBJECTIVE: We sought to assess the safety and tightening efficacy of a novel microfocused ultrasound. METHODS: The randomized middle and lower face and submental region of the participants were treated with the novel device using the following transducers: M4.5, D4.5, M3.0, and D3.0. Improvement in paired comparison of pretreatment and posttreatment photographs, three-dimensional (3D) volumetric assessments, skin thickness measured by B-ultrasonography, and skin photoaging parameters were evaluated. Adverse events and patient satisfaction were also recorded. RESULTS: A total of 20 participants (20 female) were enrolled. Fourteen of 20 participants (70%) were judged to show clinically significant facial tightening during 3-month follow-up (P < 0.05). The mean volumetric change in the lower face, as quantitatively assessed after 3 months was -0.29 mL compared with +0.42 mL on the control side (P < 0.05). The VAS pain score was 3.00 ± 1.19 without any oral or intramuscular anesthesia. CONCLUSIONS: A small sample size, lack of clinical scales, and impersonalized treatment parameters. The novel microfocused ultrasound appears to be a safe and effective modality for lower-face tightening. CLINICAL TRIAL REGISTRATION NUMBER: ChiCTR 2200064666.
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Liquid-liquid phase separation (LLPS) of fused in sarcoma (FUS) has emerged as a fundamental principle underpinning cellular function and malfunction. However, we know little about the FUS phase transition process from individual molecules to nanoscale condensates, which plays important roles in neurodegenerative diseases. Here, we propose the fluorescence correlation spectroscopy (FCS) method to quantitatively study the phase separation process of FUS protein with the fluorescent tag-enhanced green fluorescent protein (EGFP), from individual molecules to nanoscale condensates. The characteristic diffusion time (τD) of the protein condensates can be obtained from the FCS curve, which increases with the growth of the protein hydration radius. The bigger the τD value of the protein condensates, the larger the condensates formed by the phase separation of FUS. By this method, we discovered that the critical concentration for FUS to phase separation was 20 nM. We then plotted FUS phase diagrams based on τD under different concentrations of NaCl and found that both low-salt and high-salt concentrations tended to promote FUS-EGFP phase separation. Our results showed that ATP has a good inhibitory effect on FUS phase separation, and its inhibition constant IC50 was 3.2 mM. Finally, we evaluated the inhibition efficiency of single-stranded DNA sequences (ssDNA) on FUS phase separation and demonstrated that ssDNA containing three copies of TCCCCGT had relatively strong inhibition efficiency. In summary, our work provides detailed insight into the FUS phase transition process from individual molecules to nanoscale condensates at nanomolar concentrations and can be exploited for drug screening of neurodegenerative diseases.
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Proteína FUS de Ligação a RNA , Humanos , Doenças Neurodegenerativas/metabolismo , Separação de Fases , Análise Espectral , Proteína FUS de Ligação a RNA/químicaRESUMO
The Coding Region Determinant-Binding Protein (CRDBP) is a carcinoembryonic protein, and it is overexpressed in various cancer cells in the form of granules. We speculated the formation of CRDBP granules possibly through liquid-liquid phase separation (LLPS) processes due to the existence of intrinsically disordered regions (IDRs) in CRDBP. So far, we did not know whether or how phase separation processes of CRDBP occur in single living cells due to the lack of in vivo methods for studying intracellular protein phase separation. Therefore, to develop an in situ method for studying protein phase separation in living cells is a very urgent task. In this work, we proposed an efficient method for studying phase separation behavior of CRDBP in a single living cell by combining in situ fluorescence correlation spectroscopy (FCS) and fluorescence cross-correlation spectroscopy (FCCS) with a fluorescence protein fusion technique. We first predicted and confirmed that CRDBP has phase separation in solution by conventional fluorescence imaging and FCS methods. And then, we in situ studied the phase separation behaviors of CRDBP in living cells and observed three states of CRDBP phase separation such as monomer state, cluster state, and granule state. We studied the effects of CRDBP truncated forms and its inhibitor on the CRDBP phase separation. Furthermore, we discovered the recruitment of CRDBP to ß-catenin protein in living cells and investigated the effects of CRDBP structures and inhibitor on CRDBP recruitment behavior. This finding may help us to further understand the mechanism of CRDBP protein for regulating Wnt signaling pathway. Additionally, our results documented that FCS/FCCS is an efficient and alternative method for studying protein phase separation in situ in living cells.
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Proteínas de Transporte , Proteínas Intrinsicamente Desordenadas , Proteínas de Transporte/metabolismo , Cateninas/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Grânulos Citoplasmáticos/metabolismoRESUMO
Objective: A protein-based leaking-proof theranostic nanoplatform for dual-modality imaging-guided tumor photodynamic therapy (PDT) has been designed. Impact Statement: A site-specific conjugation of chlorin e6 (Ce6) to ferrimagnetic ferritin (MFtn-Ce6) has been constructed to address the challenge of unexpected leakage that often occurs during small-molecule drug delivery. Introduction: PDT is one of the most promising approaches for tumor treatment, while a delivery system is typically required for hydrophobic photosensitizers. However, the nonspecific distribution and leakage of photosensitizers could lead to insufficient drug accumulation in tumor sites. Methods: An engineered ferritin was generated for site-specific conjugation of Ce6 to obtain a leaking-proof delivery system, and a ferrimagnetic core was biomineralized in the cavity of ferritin, resulting in a fluorescent ferrimagnetic ferritin nanoplatform (MFtn-Ce6). The distribution and tumor targeting of MFtn-Ce6 can be detected by magnetic resonance imaging (MRI) and fluorescence imaging (FLI). Results: MFtn-Ce6 showed effective dual-modality MRI and FLI. A prolonged in vivo circulation and increased tumor accumulation and retention of photosensitizer was observed. The time-dependent distribution of MFtn-Ce6 can be precisely tracked in real time to find the optimal time window for PDT treatment. The colocalization of ferritin and the iron oxide core confirms the high stability of the nanoplatform in vivo. The results showed that mice treated with MFtn-Ce6 exhibited marked tumor-suppressive activity after laser irradiation. Conclusion: The ferritin-based leaking-proof nanoplatform can be used for the efficient delivery of the photosensitizer to achieve an enhanced therapeutic effect. This method established a general approach for the dual-modality imaging-guided tumor delivery of PDT agents.
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BACKGROUND: Cutaneous erythema is one of the most common signs of arteriovenous malformations (AVMs) in the head and neck region, influencing aesthetic appearance. Surgical resection of AVMs may lead to cicatrization of the skin or aggravation of the lesion. Laser treatment, although effective in improving superficial vascular lesions, cannot prevent deep AVMs from further development. OBJECTIVE: The authors propose an absolute ethanol embolization therapy that can effectively and safely eradicate the nidus with a favorable aesthetic outcome. METHODS: The authors conducted a retrospective observational study of 14 AVM patients with distinct cutaneous erythema in the head and neck region undergoing embolotherapy in a single primary care center. Symptoms before and after treatment, complications, and degree of devascularization were recorded and assessed. Changes in cutaneous redness were evaluated using a previously reported quantitative measurement. RESULTS: Complete symptomatic relief was observed in 5 patients, and major improvement was observed in 9 patients. The mean Δ a * value of the color change had a significant reduction of 6.50 ± 4.04, p < .001, indicating a remarkable remission of cutaneous erythema. CONCLUSION: Ethanol embolization is an effective and safe treatment for head and neck AVMs with excellent aesthetic outcomes and might become a potential treatment method for other superficial vascular anomalies.
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Malformações Arteriovenosas , Embolização Terapêutica , Humanos , Etanol/uso terapêutico , Resultado do Tratamento , Malformações Arteriovenosas/cirurgia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Eritema/etiologia , Eritema/terapia , Estudos RetrospectivosRESUMO
Image inpainting is an active area of research in image processing that focuses on reconstructing damaged or missing parts of an image. The advent of deep learning has greatly advanced the field of image restoration in recent years. While there are many existing methods that can produce high-quality restoration results, they often struggle when dealing with images that have large missing areas, resulting in blurry and artifact-filled outcomes. This is primarily because of the presence of invalid information in the inpainting region, which interferes with the inpainting process. To tackle this challenge, the paper proposes a novel approach called separable mask update convolution. This technique automatically learns and updates the mask, which represents the missing area, to better control the influence of invalid information within the mask area on the restoration results. Furthermore, this convolution method reduces the number of network parameters and the size of the model. The paper also introduces a regional normalization technique that collaborates with separable mask update convolution layers for improved feature extraction, thereby enhancing the quality of the restored image. Experimental results demonstrate that the proposed method performs well in restoring images with large missing areas and outperforms state-of-the-art image inpainting methods significantly in terms of image quality.
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Liupao tea as a type of dark tea can relieve irritable bowel syndrome by regulating gut microbiota, but the mechanism has not been fully explained. An ultra-high performance liquid chromatography along with quadrupole time of flight tandem mass spectrometry was used to analyze the phytochemicals in Liupao tea. Then, we explored the effects of Liupao tea against IBS. From the results of chemical analysis, we identified catechins, polyphenols, amino acids, caffeine, polysaccharides and other components in Liupao tea. The open-field test, gastrointestinal function-related indexes, histochemical assays, measurements of cytokine and aquaporin 3 (AQP3), and determination of serum metabolites were utilized to monitor the physiological consequences of Liupao tea administration in rats with irritable bowel syndrome. The results showed that Liupao tea had a significant protective effect on irritable bowel syndrome. Liupao tea increased locomotive velocity while reducing interleukin-6, interleukin-1ß, and tumor necrosis factor-α levels, as well as gastrointestinal injury. Moreover, Liupao tea increased the AQP3 levels of renal tissues but reduced the AQP3 levels of gastrointestinal tissues. Liupao tea reduced the Firmicutes/Bacteroides ratio and significantly reconstructed the microbial pattern. Liupao tea relieved irritable bowel syndrome by repairing gastrointestinal dysfunction, regulating the secretion of pro-inflammatory cytokines, modulating water metabolism, and restoring microbial homeostasis.
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Introduction: Roxadustat treatment in PD patients is equivalent to ESAs in increasing hemoglobin (Hb). But blood pressure, cardiovascular parameters, cardio-cerebrovascular complications and prognosis in the two groups before and after treatment has not been sufficiently discussed. Methods: Sixty PD patients who were treated with roxadustat for renal anemia in our PD center recruited from June 2019 to April 2020 as roxadustat group. PD patients treated with rHuEPO were enrolled at a 1:1 ratio as rHuEPO group using the method of propensity score matching. Hb, blood pressure, cardiovascular parameters, cardio-cerebrovascular complications and prognosis were compared between the two group. All patients were followed up for at least 24 months. Results: There were no significant differences in baseline clinical data or laboratory values between roxadustat group and rHuEPO group. After 24 months of follow-up, there was no significant difference in Hb levels (p > 0.05). There were no significant changes in blood pressure, or the incidence of nocturnal hypertension before and after treatment in roxadustat group (p > 0.05), while blood pressure significantly increased in rHuEPO group after treatment (p < 0.05). Compared with roxadustat group after follow-up, rHuEPO group had a higher incidence of hypertension, the levels of cardiovascular parameters were worse and cardio-cerebrovascular complications had a higher incidence (p < 0.05). Cox regression analysis showed age, systolic blood pressure, fasting blood glucose, and rHuEPO use before baseline were risk factors for cardio-cerebrovascular complications in PD patients, while treatment with roxadustat was a protective factor for cardiovascular and cerebrovascular complications. Conclusion: Compared with rHuEPO, roxadustat had less influence on blood pressure or cardiovascular parameters, and it was associated with a lower risk of cardio-cerebrovascular complications in patients undergoing PD. Roxadustat has a cardio-cerebrovascular protective advantage in PD patients with renal anemia.
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The metabolic reprogramming of tumors requires high levels of adenosine triphosphate (ATP) to maintain therapeutic resistance, posing a major challenge for photothermal therapy (PTT). Although raising the temperature helps in tumor ablation, it frequently leads to severe side effects. Therefore, improving the therapeutic response and promoting healing are critical considerations in the development of PTT. Here, we proposed a gas-mediated energy remodeling strategy to improve mild PTT efficacy while minimizing side effects. In the proof-of-concept study, a Food and Drug Administration (FDA)-approved drug-based hydrogen sulfide (H2 S) donor was developed to provide a sustained supply of H2 S to tumor sites, serving as an adjuvant to PTT. This approach proved to be highly effective in disrupting the mitochondrial respiratory chain, inhibiting ATP generation, and reducing the overexpression of heat shock protein 90 (HSP90), which ultimately amplified the therapeutic outcome. With the ability to reverse tumor thermotolerance, this strategy delivered a greatly potent antitumor response, achieving complete tumor ablation in a single treatment while minimizing harm to healthy tissues. Thus, it holds great promise to be a universal solution for overcoming the limitations of PTT and may serve as a valuable paradigm for the future clinical translation of photothermal nanoagents.
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Nanopartículas , Neoplasias , Humanos , Terapia Fototérmica , Neoplasias/tratamento farmacológico , Temperatura , Linhagem Celular Tumoral , Nanopartículas/uso terapêutico , FototerapiaRESUMO
Inorganic mineral particles play an important role in the formation of atmospheric aerosols in the Sichuan Basin. Atmospheric haze formation is accompanied by the phase transition of mineral particles under high humidity and stable climatic conditions. Backward trajectory analysis was used in this study to determine the migration trajectory of atmospheric mineral particles. Furthermore, Positive matrix factorization (PMF) was used to analyze the sources of atmospheric mineral particles. The phase transition mechanisms of atmospheric mineral particles were studied using ion chromatography, inductively coupled plasma emission spectrometry, total organic carbon analysis, X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy coupled with energy dispersive spectrometry, and grand canonical Monte Carlo methods. Three migration and phase transition paths were identified for the mineral particles. Sources of atmospheric mineral particles included combustion, vehicle emissions, industrial emissions, agricultural sources, and mineral dust. The main mineral phases in atmospheric particles, calcite and dolomite, were transformed into gypsum, and muscovite may be transformed into kaolinite. The phase transition of mineral particles seriously affects the formation of aerosols and worsens haze. Typically, along the Nanchong-Suining-Neijiang-Zigong-Yibin path, calcite is converted into gypsum under the influence of man-made inorganic pollution gases, which worsen the haze conditions and cause slight air pollution for 3-5 days. However, along the Guangyuan-Mianyang-Deyang-Chengdu-Meishan-Ya'an path, anthropogenic volatile organic compounds (VOCs) hindered gypsum formation from dolomite. Furthermore, dolomite and VOCs formed stable adsorption systems (system energies from -0.41 to -4.76 eV, long bonds from 0.20 to 0.24 nm). The adsorption system of dolomite and m/p-xylene, with low system energy (-1.46 eV/-1.33 eV) and significant correlation (r2 = 0.991, p < 0.01), was the main cause of haze formation. Consequently, calcite gypsification and dolomite--VOC synergism exacerbated regional haze conditions. This study provides a theoretical reference for the mechanism of aerosol formation in basin climates.
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Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Humanos , Poluentes Atmosféricos/análise , Compostos Orgânicos Voláteis/análise , Sulfato de Cálcio/análise , Estações do Ano , Carbonato de Cálcio/análise , Emissões de Veículos/análise , Aerossóis/análise , Monitoramento Ambiental/métodos , ChinaRESUMO
OBJECTIVE: We aimed to compare clinical and survival differences between B-cell (B-NHL) and NKT-cell non-Hodgkin lymphomas (NKT-NHL) located in the nasal cavity (NC), nasopharynx, and paranasal sinuses, which are always categorized as one sinonasal type. STUDY DESIGN: Patients diagnosed with primary B-NHL and NKT-NHL in the nasal cavity, nasopharynx, and paranasal sinuses from Surveillance, Epidemiology, and End Results (SEER) database were included (1975-2017). SETTING: Population-based cohort study. METHODS: We conducted univariate and multivariate Cox regressions and Kaplan-Meier analysis to examine survival outcomes of B/NKT-NHL in the nasal cavity, nasopharynx, and paranasal sinuses, respectively. RESULTS: Overall, most B-NHL cases originated from the nasopharynx, while the majority of NKT-NHL cases occurred in the nasal cavity. Notably, the cancer-special survival (CSS) outcomes improved significantly in all sinonasal B-NHL cases over time, whereas no such improvement trend was observed in each sinonasal NKT-NHL type. Additionally, increasing age was linked with an elevated risk of death in B-NHL, particularly in the nasal cavity (Hazard ratio [HR]: 3.37), rather than in NKT-NHL. Compared with B-NHL, the adverse effect of a higher stage on CSS was more evident in NKT-NHL, particularly in its nasopharynx site (HR: 5.12). Furthermore, radiotherapy was beneficial for survival in patients with sinonasal B-NHL and NKT-NHL, except in the nasopharynx NKT-NHL. However, chemotherapy has only been beneficial for CSS in patients with paranasal sinuses B-NHL (HR: 0.42) since 2010, rather than in other types of B/NKT-NHL. CONCLUSION: Although B-NHL and NKT-NHL in the nasal cavity, nasopharynx and paranasal sinuses have similar anatomical locations, their clinicodemographics and prognoses are largely different and should be treated and studied as distinct diseases.