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1.
J Zhejiang Univ Sci B ; 25(6): 499-512, 2024 Jun 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-38910495

RESUMO

Artificial vascular graft (AVG) fistula is widely used for hemodialysis treatment in patients with renal failure. However, it has poor elasticity and compliance, leading to stenosis and thrombosis. The ideal artificial blood vessel for dialysis should replicate the structure and components of a real artery, which is primarily maintained by collagen in the extracellular matrix (ECM) of arterial cells. Studies have revealed that in hepatitis B virus (HBV)-induced liver fibrosis, hepatic stellate cells (HSCs) become hyperactive and produce excessive ECM fibers. Furthermore, mechanical stimulation can encourage ECM secretion and remodeling of a fiber structure. Based on the above factors, we transfected HSCs with the hepatitis B viral X (HBX) gene for simulating the process of HBV infection. Subsequently, these HBX-HSCs were implanted into a polycaprolactone-polyurethane (PCL-PU) bilayer scaffold in which the inner layer is dense and the outer layer consists of pores, which was mechanically stimulated to promote the secretion of collagen nanofiber from the HBX-HSCs and to facilitate crosslinking with the scaffold. We obtained an ECM-PCL-PU composite bionic blood vessel that could act as access for dialysis after decellularization. Then, the vessel scaffold was implanted into a rabbit's neck arteriovenous fistula model. It exhibited strong tensile strength and smooth blood flow and formed autologous blood vessels in the rabbit's body. Our study demonstrates the use of human cells to create biomimetic dialysis blood vessels, providing a novel approach for creating clinical vascular access for dialysis.


Assuntos
Células Estreladas do Fígado , Poliésteres , Diálise Renal , Coelhos , Animais , Poliésteres/química , Proteínas Virais Reguladoras e Acessórias , Alicerces Teciduais , Transfecção , Biônica , Poliuretanos , Prótese Vascular , Matriz Extracelular/metabolismo , Humanos , Vírus da Hepatite B/genética , Colágeno , Engenharia Tecidual/métodos , Transativadores
2.
Genes (Basel) ; 15(6)2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38927696

RESUMO

Small auxin-upregulated RNAs (SAURs), as the largest family of early auxin-responsive genes, play important roles in plant growth and development processes, such as auxin signaling and transport, hypocotyl development, and tolerance to environmental stresses. However, the functions of few SAUR genes are known in the root development of sweet potatoes. In this study, an IbSAUR36 gene was cloned and functionally analyzed. The IbSAUR36 protein was localized to the nucleus and plasma membrane. The transcriptional level of this gene was significantly higher in the pencil root and leaf.This gene was strongly induced by indole-3-acetic acid (IAA), but it was downregulated under methyl-jasmonate(MeJA) treatment. The promoter of IbSAUR36 contained the core cis-elements for phytohormone responsiveness. Promoter ß-glucuronidase (GUS) analysis in Arabidopsis showed that IbSAUR36 is highly expressed in the young tissues of plants, such as young leaves, roots, and buds. IbSAUR36-overexpressing sweet potato roots were obtained by an efficient Agrobacterium rhizogenes-mediated root transgenic system. We demonstrated that overexpression of IbSAUR36 promoted the accumulation of IAA, upregulated the genes encoding IAA synthesis and its signaling pathways, and downregulated the genes encoding lignin synthesis and JA signaling pathways. Taken together, these results show that IbSAUR36 plays an important role in adventitious root (AR) development by regulating IAA signaling, lignin synthesis, and JA signaling pathways in transgenic sweet potatoes.


Assuntos
Regulação da Expressão Gênica de Plantas , Ácidos Indolacéticos , Ipomoea batatas , Proteínas de Plantas , Raízes de Plantas , Plantas Geneticamente Modificadas , Ipomoea batatas/genética , Ipomoea batatas/crescimento & desenvolvimento , Ipomoea batatas/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Ácidos Indolacéticos/metabolismo , Ácidos Indolacéticos/farmacologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Reguladores de Crescimento de Plantas/metabolismo , Reguladores de Crescimento de Plantas/genética , Regiões Promotoras Genéticas , Ciclopentanos/farmacologia , Ciclopentanos/metabolismo
3.
Sci Rep ; 14(1): 13424, 2024 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-38862629

RESUMO

**Ischemic stroke remains a leading cause of morbidity and mortality globally. Despite the advances in thrombolytic therapy, notably recombinant tissue plasminogen activator (rtPA), patient outcomes are highly variable. This study aims to introduce a novel predictive model, the Acute Stroke Thrombolysis Non-Responder Prediction Model (ASTN-RPM), to identify patients unlikely to benefit from rtPA within the critical early recovery window. We conducted a retrospective cohort study at Baoding No.1 Central Hospital including 709 adult patients diagnosed with acute ischemic stroke and treated with intravenous alteplase within the therapeutic time window. The ASTN-RPM was developed using Least Absolute Shrinkage and Selection Operator (LASSO) regression technique, incorporating a wide range of biomarkers and clinical parameters. Model performance was evaluated using Receiver Operating Characteristic (ROC) curves, calibration plots, and Decision Curve Analysis (DCA). ASTN-RPM effectively identified patients at high risk of poor response to thrombolysis, with an AUC of 0.909 in the training set and 0.872 in the validation set, indicating high sensitivity and specificity. Key predictors included posterior circulation stroke, high admission NIHSS scores, extended door to needle time, and certain laboratory parameters like homocysteine levels. The ASTN-RPM stands as a potential tool for refining clinical decision-making in ischemic stroke management. By anticipating thrombolytic non-response, clinicians can personalize treatment strategies, possibly improving patient outcomes and reducing the burden of ineffective interventions. Future studies are needed for external validation and to explore the incorporation of emerging biomarkers and imaging data.


Assuntos
Biomarcadores , AVC Isquêmico , Terapia Trombolítica , Ativador de Plasminogênio Tecidual , Humanos , AVC Isquêmico/tratamento farmacológico , AVC Isquêmico/diagnóstico , Masculino , Biomarcadores/sangue , Feminino , Terapia Trombolítica/métodos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Ativador de Plasminogênio Tecidual/uso terapêutico , Ativador de Plasminogênio Tecidual/administração & dosagem , Fibrinolíticos/uso terapêutico , Fibrinolíticos/administração & dosagem , Curva ROC , Resultado do Tratamento
4.
Gastrointest Endosc ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851456

RESUMO

BACKGROUND AND AIMS: Despite the benefits of artificial intelligence (AI) in small bowel (SB) capsule endoscopy (CE) image reading, information on its application in the stomach and SB CE is lacking. METHODS: In this multicenter, retrospective diagnostic study, gastric imaging data were added to the deep learning (DL)-based SmartScan (SS), which has been described previously. A total of 1,069 magnetically controlled gastrointestinal (GI) CE examinations (comprising 2,672,542 gastric images) were used in the training phase for recognizing gastric pathologies, producing a new AI algorithm named SS Plus. 342 fully automated, magnetically controlled CE (FAMCE) examinations were included in the validation phase. The performance of both senior and junior endoscopists with both the SS Plus-Assisted Reading (SSP-AR) and conventional reading (CR) modes was assessed. RESULTS: SS Plus was designed to recognize 5 types of gastric lesions and 17 types of SB lesions. SS Plus reduced the number of CE images required for review to 873.90 (1000) (median, IQR 814.50-1,000) versus 44,322.73 (42,393) (median, IQR 31,722.75-54,971.25) for CR. Furthermore, with SSP-AR, endoscopists took 9.54 min (8.51) (median, IQR 6.05-13.13) to complete the CE video reading. In the 342 CE videos, SS Plus identified 411 gastric and 422 SB lesions, whereas 400 gastric and 368 intestinal lesions were detected with CR. Moreover, junior endoscopists remarkably improved their CE image reading ability with SSP-AR. CONCLUSIONS: Our study shows that the newly upgraded DL-based algorithm SS Plus can detect GI lesions and help improve the diagnostic performance of junior endoscopists in interpreting CE videos.

5.
Reprod Toxicol ; : 108648, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909692

RESUMO

Previous retrospective cohort studies have found that, compared with oxygen tension in the uterus and fallopian tubes (2%-8%), exposure of pre-implantation embryos to atmospheric oxygen tension (AtmO2, 20%) during assisted reproductive technology(ART) can affect embryo quality, pregnancy outcomes and offspring health. However, current research on the effects and mechanisms of AtmO2 on the development of embryos and offspring is mainly limited to animal experiments. Human embryonic stem cells (hESCs) play a special and irreplaceable role in the study of early human embryonic development. In this study, we used hESCs as a model to elucidate the possible effects and mechanisms of AtmO2 exposure on human embryonic development. We found that exposure to AtmO2 can reduce cell viability, produce oxidative stress, increase DNA damage, initiate DNA repair, activate autophagy, and increase cell apoptosis. We also noticed that approximately 50% of hESCs survived, adapted and proliferated through high expression of self-renewal and pluripotency regulatory factors, and affected embryoid body differentiation. These data indicate that hESCs experience oxidative stress, accumulation of DNA damage, and activate DNA damage response under the selective pressure of AtmO2.Some hESCs undergo cell death, whereas other hESCs adapt and proliferate through increased expression of self-renewal genes. The current findings provide in vitro evidence that exposure to AtmO2 during the early preimplantation stage negatively affects hESCs.

6.
J Adv Res ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38879123

RESUMO

INTRODUCTION: The interplay between influential factors and the incidence of subthreshold depression (SD) in young adults remains poorly understood. OBJECTIVES: This study sought to understand the dietary habits, gut microbiota composition, etc. among individuals with SD in young adults and to investigate their association with SD occurrence. METHODS: Employing a cross-sectional approach, 178 individuals with SD, aged 18-32 years, were matched with 114 healthy counterparts. SD status was evaluated using the Zung Self-rating Depression Scale (SDS), Zung Self-rating Anxiety Scale (SAS), Beck Depression Inventory 2nd version (BDI-II), the 17-item Hamilton Rating Scales of Depression (HAMD-17), and Pittsburgh Sleep Quality Index (PSQI). Metagenomic sequencing was utilized to identify fecal microbial profiles. Dietary patterns were discerned via factor analysis of a 25-item food frequency questionnaire (FFQ). Logistic regression analysis and mediation analysis were performed to explore the potential links between gut microbiota, dietary patterns, and incident SD. RESULTS: Data on dietary habits were available for 292 participants (mean [SD] age, 22.1 [2.9] years; 216 [73.9 %] female). Logistic regression analysis revealed that dietary patterns Ⅰ (odds ratio [OR], 0.34; 95 % CI, 0.15-0.75) and IV (OR, 0.39; 95 % CI, 0.17-0.86 and OR, 0.39; 95 % CI, 0.18-0.84) were associated with reduced risk of SD. Distinct microbial profiles were observed in young adults with SD, marked by increased microbial diversity and taxonomic alterations. Moreover, mediation analysis suggested Veillonella atypica as a potential mediator linking SDS or BDI-II scores with a healthy dietary pattern rich in bean products, coarse grains, nuts, fruits, mushrooms, and potatoes (ß = 0.25, 95 % CI: 0.02-0.78 and ß = 0.18, 95 % CI: 0.01-0.54). CONCLUSIONS: Our findings highlight the complex interplay between dietary patterns, gut microbiota, and the risk of developing SD in young adults, underscoring the potential for dietary interventions and microbiome modulation in mental health promotion.

7.
Science ; 384(6698): 878-884, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38781395

RESUMO

Mechanical failure and chemical degradation of device heterointerfaces can strongly influence the long-term stability of perovskite solar cells (PSCs) under thermal cycling and damp heat conditions. We report chirality-mediated interfaces based on R-/S-methylbenzyl-ammonium between the perovskite absorber and electron-transport layer to create an elastic yet strong heterointerface with increased mechanical reliability. This interface harnesses enantiomer-controlled entropy to enhance tolerance to thermal cycling-induced fatigue and material degradation, and a heterochiral arrangement of organic cations leads to closer packing of benzene rings, which enhances chemical stability and charge transfer. The encapsulated PSCs showed retentions of 92% of power-conversion efficiency under a thermal cycling test (-40°C to 85°C; 200 cycles over 1200 hours) and 92% under a damp heat test (85% relative humidity; 85°C; 600 hours).

8.
Nanomicro Lett ; 16(1): 191, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38700650

RESUMO

Low-temperature processed electron transport layer (ETL) of TiO2 that is widely used in planar perovskite solar cells (PSCs) has inherent low carrier mobility, resulting in insufficient photogenerated electron transport and thus recombination loss at buried interface. Herein, we demonstrate an effective strategy of laser embedding of p-n homojunctions in the TiO2 ETL to accelerate electron transport in PSCs, through localized build-in electric fields that enables boosted electron mobility by two orders of magnitude. Such embedding is found significantly helpful for not only the enhanced crystallization quality of TiO2 ETL, but the fabrication of perovskite films with larger-grain and the less-trap-states. The embedded p-n homojunction enables also the modulation of interfacial energy level between perovskite layers and ETLs, favoring for the reduced voltage deficit of PSCs. Benefiting from these merits, the formamidinium lead iodide (FAPbI3) PSCs employing such ETLs deliver a champion efficiency of 25.50%, along with much-improved device stability under harsh conditions, i.e., maintain over 95% of their initial efficiency after operation at maximum power point under continuous heat and illumination for 500 h, as well as mixed-cation PSCs with a champion efficiency of 22.02% and over 3000 h of ambient storage under humidity stability of 40%. Present study offers new possibilities of regulating charge transport layers via p-n homojunction embedding for high performance optoelectronics.

9.
Surg Innov ; 31(3): 307-317, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38606504

RESUMO

BACKGROUND: Reconstructing bone defects in the upper extremities and restoring their functions poses a significant challenge. In this study, we describe a novel workflow for designing and manufacturing customized bone cement molds using 3D printing technology to reconstruct upper extremity defects after bone tumor resection. METHODS: Computer tomography data was acquired from the unaffected upper extremities to create a detachable mold, which can be customized to fit the joint precisely by shaping the bone cement accordingly. Fourteen patients who underwent reconstructive surgery following bone tumor resection in the proximal humerus (13 cases) or distal radius (1 case) between January 2014 and December 2022 were retrospectively evaluated. The medical records of this case series were reviewed for the demographic, radiological, and operative data. Metastasis, local recurrence, and complication were also reviewed. Additionally, Musculoskeletal Tumor Society Score (MSTS) and Visual Analogue Scale (VAS) were used to assess clinical outcomes. RESULTS: The mean follow-up period was 49.36 ± 15.18 months (range, 27-82 months). At the end of follow-up, there were no cases of metastasis or recurrence, and patients did not experience complications such as infection, dislocation, or implant loosening. Two cases complicated with subluxation (14.3%), and 1 case underwent revision surgery for prosthetic fracture (7.1%). The average MSTS score was 23.2 ± 1.76 (77.4%, range, 66.7%-86.7%), and the postoperative VAS score was 1.86 ± 1.03 (range, 1-4), which was significantly lower than that before surgery (average preoperative VAS score was 5.21 ± 2.00 (range, 2-8)) (P < .001). CONCLUSION: Customized 3D molds can be utilized to shape bone cement prostheses, which may serve as a potential alternative for reconstructing the proximal humerus and distal radius following en bloc resection of bone tumors. This reconstruction strategy offers apparent advantages, including precise matching of articular surfaces and comparatively reduced costs.


Assuntos
Cimentos Ósseos , Neoplasias Ósseas , Procedimentos de Cirurgia Plástica , Impressão Tridimensional , Humanos , Cimentos Ósseos/uso terapêutico , Neoplasias Ósseas/cirurgia , Feminino , Masculino , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Adulto , Pessoa de Meia-Idade , Extremidade Superior/cirurgia , Rádio (Anatomia)/cirurgia , Adulto Jovem , Úmero/cirurgia , Adolescente , Idoso , Tomografia Computadorizada por Raios X
10.
Food Funct ; 15(8): 4527-4537, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38576413

RESUMO

Artificial sweeteners (ASs) have been widely added to food and beverages because of their properties of low calories and sweet taste. However, whether the consumption of ASs is causally associated with cancer risk is not clear. Here, we utilized the two-sample Mendelian randomization (MR) method to study the potential causal association. Genetic variants like single-nucleotide polymorphisms (SNPs) associated with exposure (AS consumption) were extracted from a genome-wide association study (GWAS) database including 64 949 Europeans and the influence of confounding was removed. The outcome was from 98 GWAS data and included several types of cancers like lung cancer, colorectal cancer, stomach cancer, breast cancer, and so on. The exposure-outcome SNPs were harmonized and then MR analysis was performed. The inverse-variance weighted (IVW) with random effects was used as the main analytical method accompanied by four complementary methods: MR Egger, weighted median, simple mode, and weighted mode. Sensitivity analyses consisted of heterogeneity, pleiotropy, and leave-one-out analysis. Our results demonstrated that ASs added to coffee had a positive association with high-grade and low-grade serous ovarian cancer; ASs added to tea had a positive association with oral cavity and pharyngeal cancers, but a negative association with malignant neoplasm of the bronchus and lungs. No other cancers had a genetic causal association with AS consumption. Our MR study revealed that AS consumption had no genetic causal association with major cancers. Larger MR studies or RCTs are needed to investigate small effects and support this conclusion.


Assuntos
Estudo de Associação Genômica Ampla , Análise da Randomização Mendeliana , Neoplasias , Polimorfismo de Nucleotídeo Único , Edulcorantes , Humanos , Feminino , Neoplasias/genética , Edulcorantes/efeitos adversos , Chá , Café , Neoplasias Ovarianas/genética , Fatores de Risco
11.
J Nat Med ; 78(3): 702-708, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38662303

RESUMO

Two new sesterterpenoids, atractylodes japonica terpenoid acid I (1) and atractylodes japonica terpenoid aldehyde I (2), were isolated from the rhizomes of Atractylodes japonica Koidz. ex Kitam together with ten known compounds (3-12). Their structures were elucidated on the basis of comprehensive spectroscopic analysis (1D/2D NMR, HRESIMS and IR). In addition, all of these isolated compounds were evaluated for their cytotoxic activities against human gastric cancer cell MGC-803 and human hepatocellular cancer cell HepG-2. Most of them exhibited moderate to weak inhibitory effects with IC50 values in the range of 25.15-88.85 µM except for 9-12.


Assuntos
Atractylodes , Rizoma , Sesterterpenos , Atractylodes/química , Humanos , Estrutura Molecular , Linhagem Celular Tumoral , Sesterterpenos/química , Sesterterpenos/farmacologia , Sesterterpenos/isolamento & purificação , Rizoma/química , Células Hep G2 , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Espectroscopia de Ressonância Magnética , Extratos Vegetais/química , Extratos Vegetais/farmacologia
12.
Small Methods ; : e2400007, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38573877

RESUMO

The development of non-precious hydrogen oxidation reaction (HOR) catalysts is a major challenge for the commercialization of Pt-free fuel cells. Herein, a temperature-induced phase hybridization method is reported that greatly improves the catalytic performance of NiCu alloy for the HOR. The migration of W atoms hybridizes the interface of tungsten oxide (WOx) and tungsten carbide (WC) at the onset reduction temperature of WOx, leading to a greatly weakened H binding energy and an optimized OH binding energy, which endows NiCuW/WOx-WC@WC with favorable stability and CO resistance during HOR. The hybridization catalysts deliver a high mass activity of 29.37 mA mg-1 Ni and reach a peak power of 298 mW.cm-2 in H2-O2 anion exchange membrane fuel cells (AEMFCs).

13.
Int Immunopharmacol ; 133: 112004, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38613881

RESUMO

Silicosis is a hazardous occupational disease caused by inhalation of silica, characterized by persistent lung inflammation that leads to fibrosis and subsequent lung dysfunction. Moreover, the complex pathophysiology of silicosis, the challenges associated with early detection, and the unfavorable prognosis contribute to the limited availability of treatment options. Daphnetin (DAP), a natural lactone, has demonstrated various pharmacological properties, including anti-inflammatory, anti-fibrotic, and pulmonary protective effects. However, the effects of DAP on silicosis and its molecular mechanisms remain uncover. This study aimed to evaluate the therapeutic effects of DAP against pulmonary inflammation and fibrosis using a silica-induced silicosis mouse model, and investigate the potential mechanisms and targets through network pharmacology, proteomics, molecular docking, and cellular thermal shift assay (CETSA). Here, we found that DAP significantly alleviated silica-induced lung injury in mice with silicosis. The results of H&E staining, Masson staining, and Sirius red staining indicated that DAP effectively reduced the inflammatory response and collagen deposition over a 28-day period following lung exposure to silica. Furthermore, DAP reduced the number of TUNEL-positive cells, increased the expression levels of Bcl-2, and decreased the expression of Bax and cleaved caspase-3 in the mice with silicosis. More importantly, DAP suppressed the expression levels of NLRP3 signaling pathway-related proteins, including NLRP3, ASC, and cleaved caspase-1, thereby inhibiting silica-induced lung inflammation. Further studies demonstrated that DAP possesses the ability to inhibit the epithelial mesenchymal transition (EMT) induced by silica through the inhibition of the TGF-ß1/Smad2/3 signaling pathway. The experimental results of proteomic analysis found that the PI3K/AKT1 signaling pathway was the key targets of DAP to alleviate lung injury induced by silica. DAP significantly inhibited the activation of the PI3K/AKT1 signaling pathway induced by silica in lung tissues. The conclusion was also verified by the results of molecular and CETSA. To further verify this conclusion, the activity of PI3K/AKT1 signaling pathway was inhibited in A549 cells using LY294002. When the A549 cells were pretreated with LY294002, the protective effect of DAP on silica-induced injury was lost. In conclusion, the results of this study suggest that DAP alleviates pulmonary inflammation and fibrosis induced by silica by modulating the PI3K/AKT1 signaling pathway, and holds promise as a potentially effective treatment for silicosis.


Assuntos
Camundongos Endogâmicos C57BL , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Fibrose Pulmonar , Transdução de Sinais , Dióxido de Silício , Silicose , Umbeliferonas , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Umbeliferonas/farmacologia , Umbeliferonas/uso terapêutico , Silicose/tratamento farmacológico , Silicose/metabolismo , Fibrose Pulmonar/tratamento farmacológico , Fibrose Pulmonar/induzido quimicamente , Fosfatidilinositol 3-Quinases/metabolismo , Camundongos , Humanos , Pneumonia/tratamento farmacológico , Pneumonia/induzido quimicamente , Pneumonia/patologia , Anti-Inflamatórios/uso terapêutico , Anti-Inflamatórios/farmacologia , Masculino , Pulmão/patologia , Pulmão/efeitos dos fármacos , Modelos Animais de Doenças , Simulação de Acoplamento Molecular
14.
Reprod Biol Endocrinol ; 22(1): 51, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671458

RESUMO

BACKGROUND: Ovarian damage and follicle loss are major side effects of chemotherapy in young female patients with cancer. However, effective strategies to prevent these injuries are still lacking. The purpose of this study was to verify low-intensity pulsed ultrasound (LIPUS) can reduce ovarian injury caused by chemotherapy and to explore its underlying mechanisms in mice model. METHODS: The mice were randomly divided into the Control group, Cisplatin group, and Cisplatin + LIPUS group. The Cisplatin group and Cisplatin + LIPUS group were intraperitoneally injected with cisplatin every other day for a total of 10 injections, and the Control group was injected with saline. On the second day of each injection, the Cisplatin + LIPUS group received irradiation, whereas the other two groups received sham irradiation. We used a variety of biotechnologies to detect the differences in follicle count, granulosa cell apoptosis, fibrosis, transcriptome level, oxidative damage, and inflammation in differently treated mice. RESULT: LIPUS was able to reduce primordial follicle pool depletion induced by cisplatin and inhibit the apoptosis of granulosa cells. Transcriptomic results confirmed that LIPUS can reduce ovarian tissue injury. We demonstrated that LIPUS can relieve ovarian fibrosis by inhibiting TGF-ß1/Smads pathway. Meanwhile, it can reduce the oxidative damage and reduced the mRNA levels of proinflammatory cytokines caused by chemotherapy. CONCLUSION: LIPUS can reduce the toxic effects of chemotherapy drugs on ovaries, inhibit ovarian fibrosis, reduce the inflammatory response, and redcue the oxidative damage, reduce follicle depletion and to maintain the number of follicle pools.


Assuntos
Antineoplásicos , Cisplatino , Ovário , Ondas Ultrassônicas , Animais , Feminino , Camundongos , Cisplatino/efeitos adversos , Ovário/efeitos dos fármacos , Ovário/efeitos da radiação , Ovário/patologia , Antineoplásicos/efeitos adversos , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Folículo Ovariano/efeitos dos fármacos , Folículo Ovariano/efeitos da radiação , Terapia por Ultrassom/métodos
15.
Nature ; 629(8010): 92-97, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38503346

RESUMO

Ammonia is crucial as a fertilizer and in the chemical industry and is considered to be a carbon-free fuel1. Ammonia electrosynthesis from nitrogen under ambient conditions offers an attractive alternative to the Haber-Bosch process2,3, and lithium-mediated nitrogen reduction represents a promising approach to continuous-flow ammonia electrosynthesis, coupling nitrogen reduction with hydrogen oxidation4. However, tetrahydrofuran, which is commonly used as a solvent, impedes long-term ammonia production owing to polymerization and volatility problems. Here we show that a chain-ether-based electrolyte enables long-term continuous ammonia synthesis. We find that a chain-ether-based solvent exhibits non-polymerization properties and a high boiling point (162 °C) and forms a compact solid-electrolyte interphase layer on the gas diffusion electrode, facilitating ammonia release in the gas phase and ensuring electrolyte stability. We demonstrate 300 h of continuous operation in a flow electrolyser with a 25 cm2 electrode at 1 bar pressure and room temperature, and achieve a current-to-ammonia efficiency of 64 ± 1% with a gas-phase ammonia content of approximately 98%. Our results highlight the crucial role of the solvent in long-term continuous ammonia synthesis.

16.
Nat Commun ; 15(1): 2417, 2024 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-38499554

RESUMO

Ammonia is a crucial component in the production of fertilizers and various nitrogen-based compounds. Now, the lithium-mediated nitrogen reduction reaction (Li-NRR) has emerged as a promising approach for ammonia synthesis at ambient conditions. The proton shuttle plays a critical role in the proton transfer process during Li-NRR. However, the structure-activity relationship and design principles for effective proton shuttles have not yet been established in practical Li-NRR systems. Here, we propose a general procedure for verifying a true proton shuttle and established design principles for effective proton shuttles. We systematically evaluate several classes of proton shuttles in a continuous-flow reactor with hydrogen oxidation at the anode. Among the tested proton shuttles, phenol exhibits the highest Faradaic efficiency of 72 ± 3% towards ammonia, surpassing that of ethanol, which has been commonly used so far. Experimental investigations including operando isotope-labelled mass spectrometry proved the proton-shuttling capability of phenol. Further mass transport modeling sheds light on the mechanism.

17.
J Colloid Interface Sci ; 665: 500-509, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38547631

RESUMO

Constructing a heterojunction by combining two semiconductors with similar band structures is a successful approach to obtaining photocatalysts with high efficiency. Herein, a CuPc/DR-MoS2 heterojunction involving copper phthalocyanine (CuPc) and molybdenum disulfide with S-rich vacancies (13.66%) is successfully prepared by the facile hydrothermal method. Experimental results and theoretical calculations firmly demonstrated that photoelectrons exhibit an S-scheme charge transfer mechanism in the CuPc/DR-MoS2 heterojunction. The S-scheme heterojunction system has proven significant advantages in promoting the charge separation and transfer of photogenerated carriers, enhancing visible-light responsiveness, and achieving robust photoredox capability. As a result, the optimized 3CuPc/DR-MoS2 S-scheme heterojunction exhibits photocatalytic yields of CO and CH4 at 200 and 111.6 µmol g-1h-1, respectively. These values are four times and 4.5 times greater than the photocatalytic yields of pure DR-MoS2. This study offers novel perspectives on the advancement of innovative and highly effective heterojunction photocatalysts.

18.
Nat Commun ; 15(1): 2329, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38485944

RESUMO

Intragrain impurities can impart detrimental effects on the efficiency and stability of perovskite solar cells, but they are indiscernible to conventional characterizations and thus remain unexplored. Using in situ scanning transmission electron microscopy, we reveal that intragrain impurity nano-clusters inherited from either the solution synthesis or post-synthesis storage can revert to perovskites upon irradiation stimuli, leading to the counterintuitive amendment of crystalline grains. In conjunction with computational modelling, we atomically resolve crystallographic transformation modes for the annihilation of intragrain impurity nano-clusters and probe their impacts on optoelectronic properties. Such critical fundamental findings are translated for the device advancement. Adopting a scanning laser stimulus proven to heal intragrain impurity nano-clusters, we simultaneously boost the efficiency and stability of formamidinium-cesium perovskite solar cells, by virtual of improved optoelectronic properties and relaxed intra-crystal strain, respectively. This device engineering, inspired and guided by atomic-scale in situ microscopic imaging, presents a new prototype for solar cell advancement.

19.
Fitoterapia ; 174: 105874, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38417684

RESUMO

Five new sesquiterpenoids, dictamtrinorguaianols E and F (1-2), and dictameudesmnosides F, G, and H (3-5), along with seven known sesquiterpenoids (6-12) were isolated from Dictamnus dasycarpus Turcz. The structures of all new compounds were characterized by spectroscopic methods, including UV, IR, HR-ESI-MS, and 1D and 2D NMR. The In-vitro anti-proliferative activities of all the compounds against two human cancer cell lines (SW982 and A549) were evaluated by CCK-8 assay. Compounds 1 and 4 showed medium anti-proliferative activity against SW982 cells, with IC50 values of 3.49 ± 0.10 and 6.42 ± 1.23 µM, respectively. Additionally, compounds 2, 7, and 8 exhibited medium anti-proliferative activity against A549 cells, with IC50 values ranging from 0.80 ± 0.05 to 6.60 ± 0.46 µM.


Assuntos
Dictamnus , Sesquiterpenos , Humanos , Dictamnus/química , Estrutura Molecular , Linhagem Celular , Espectroscopia de Ressonância Magnética , Sesquiterpenos/farmacologia
20.
Comput Med Imaging Graph ; 113: 102354, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38341946

RESUMO

Lung granuloma is a very common lung disease, and its specific diagnosis is important for determining the exact cause of the disease as well as the prognosis of the patient. And, an effective lung granuloma detection model based on computer-aided diagnostics (CAD) can help pathologists to localize granulomas, thereby improving the efficiency of the specific diagnosis. However, for lung granuloma detection models based on CAD, the significant size differences between granulomas and how to better utilize the morphological features of granulomas are both critical challenges to be addressed. In this paper, we propose an automatic method CRDet to localize granulomas in histopathological images and deal with these challenges. We first introduce the multi-scale feature extraction network with self-attention to extract features at different scales at the same time. Then, the features will be converted to circle representations of granulomas by circle representation detection heads to achieve the alignment of features and ground truth. In this way, we can also more effectively use the circular morphological features of granulomas. Finally, we propose a center point calibration method at the inference stage to further optimize the circle representation. For model evaluation, we built a lung granuloma circle representation dataset named LGCR, including 288 images from 50 subjects. Our method yielded 0.316 mAP and 0.571 mAR, outperforming the state-of-the-art object detection methods on our proposed LGCR.


Assuntos
Granuloma , Pulmão , Humanos , Calibragem , Granuloma/diagnóstico por imagem , Granuloma/patologia , Pulmão/diagnóstico por imagem , Pulmão/patologia
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