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1.
Cell ; 186(18): 3968-3982.e15, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37586362

RESUMO

Ductal carcinoma in situ (DCIS) is a common precursor of invasive breast cancer. Our understanding of its genomic progression to recurrent disease remains poor, partly due to challenges associated with the genomic profiling of formalin-fixed paraffin-embedded (FFPE) materials. Here, we developed Arc-well, a high-throughput single-cell DNA-sequencing method that is compatible with FFPE materials. We validated our method by profiling 40,330 single cells from cell lines, a frozen tissue, and 27 FFPE samples from breast, lung, and prostate tumors stored for 3-31 years. Analysis of 10 patients with matched DCIS and cancers that recurred 2-16 years later show that many primary DCIS had already undergone whole-genome doubling and clonal diversification and that they shared genomic lineages with persistent subclones in the recurrences. Evolutionary analysis suggests that most DCIS cases in our cohort underwent an evolutionary bottleneck, and further identified chromosome aberrations in the persistent subclones that were associated with recurrence.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Feminino , Humanos , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Carcinoma Intraductal não Infiltrante/patologia , Progressão da Doença , Genômica/métodos , Análise da Expressão Gênica de Célula Única , Linhagem Celular Tumoral
2.
Nature ; 613(7945): 676-681, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36379225

RESUMO

The open-circuit voltage (VOC) deficit in perovskite solar cells is greater in wide-bandgap (over 1.7 eV) cells than in perovskites of roughly 1.5 eV (refs. 1,2). Quasi-Fermi-level-splitting measurements show VOC-limiting recombination at the electron-transport-layer contact3-5. This, we find, stems from inhomogeneous surface potential and poor perovskite-electron transport layer energetic alignment. Common monoammonium surface treatments fail to address this; as an alternative, we introduce diammonium molecules to modify perovskite surface states and achieve a more uniform spatial distribution of surface potential. Using 1,3-propane diammonium, quasi-Fermi-level splitting increases by 90 meV, enabling 1.79 eV perovskite solar cells with a certified 1.33 V VOC and over 19% power conversion efficiency (PCE). Incorporating this layer into a monolithic all-perovskite tandem, we report a record VOC of 2.19 V (89% of the detailed balance VOC limit) and over 27% PCE (26.3% certified quasi-steady state). These tandems retained more than 86% of their initial PCE after 500 h of operation.

3.
Nature ; 618(7963): 74-79, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36977463

RESUMO

The tunable bandgaps and facile fabrication of perovskites make them attractive for multi-junction photovoltaics1,2. However, light-induced phase segregation limits their efficiency and stability3-5: this occurs in wide-bandgap (>1.65 electron volts) iodide/bromide mixed perovskite absorbers, and becomes even more acute in the top cells of triple-junction solar photovoltaics that require a fully 2.0-electron-volt bandgap absorber2,6. Here we report that lattice distortion in iodide/bromide mixed perovskites is correlated with the suppression of phase segregation, generating an increased ion-migration energy barrier arising from the decreased average interatomic distance between the A-site cation and iodide. Using an approximately 2.0-electron-volt rubidium/caesium mixed-cation inorganic perovskite with large lattice distortion in the top subcell, we fabricated all-perovskite triple-junction solar cells and achieved an efficiency of 24.3 per cent (23.3 per cent certified quasi-steady-state efficiency) with an open-circuit voltage of 3.21 volts. This is, to our knowledge, the first reported certified efficiency for perovskite-based triple-junction solar cells. The triple-junction devices retain 80 per cent of their initial efficiency following 420 hours of operation at the maximum power point.

4.
Mol Cancer ; 23(1): 65, 2024 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-38532427

RESUMO

BACKGROUND: Abnormal angiogenesis is crucial for gallbladder cancer (GBC) tumor growth and invasion, highlighting the importance of elucidating the mechanisms underlying this process. LncRNA (long non-coding RNA) is widely involved in the malignancy of GBC. However, conclusive evidence confirming the correlation between lncRNAs and angiogenesis in GBC is lacking. METHODS: LncRNA sequencing was performed to identify the differentially expressed lncRNAs. RT-qPCR, western blot, FISH, and immunofluorescence were used to measure TRPM2-AS and NOTCH1 signaling pathway expression in vitro. Mouse xenograft and lung metastasis models were used to evaluate the biological function of TRPM2-AS during angiogenesis in vivo. EDU, transwell, and tube formation assays were used to detect the angiogenic ability of HUVECs. RIP, RAP, RNA pull-down, dual-luciferase reporter system, and mass spectrometry were used to confirm the interaction between TRPM2-AS, IGF2BP2, NUMB, and PABPC1. RESULTS: TRPM2-AS was upregulated in GBC tissues and was closely related to angiogenesis and poor prognosis in patients with GBC. The high expression level and stability of TRPM2-AS benefited from m6A modification, which is recognized by IGF2BP2. In terms of exerting pro-angiogenic effects, TRPM2-AS loaded with exosomes transported from GBC cells to HUVECs enhanced PABPC1-mediated NUMB expression inhibition, ultimately promoting the activation of the NOTCH1 signaling pathway. PABPC1 inhibited NUMB mRNA expression through interacting with AGO2 and promoted miR-31-5p and miR-146a-5p-mediated the degradation of NUMB mRNA. The NOTCH signaling pathway inhibitor DAPT inhibited GBC tumor angiogenesis, and TRPM2-AS knockdown enhanced this effect. CONCLUSIONS: TRPM2-AS is a novel and promising biomarker for GBC angiogenesis that promotes angiogenesis by facilitating the activation of the NOTCH1 signaling pathway. Targeting TRPM2-AS opens further opportunities for future GBC treatments.


Assuntos
Carcinoma in Situ , Neoplasias da Vesícula Biliar , MicroRNAs , RNA Longo não Codificante , Canais de Cátion TRPM , Humanos , Animais , Camundongos , Neoplasias da Vesícula Biliar/genética , RNA Longo não Codificante/genética , MicroRNAs/genética , Canais de Cátion TRPM/metabolismo , Angiogênese , Linhagem Celular Tumoral , Transdução de Sinais , RNA Mensageiro , Proliferação de Células , Receptor Notch1/metabolismo , Proteínas de Ligação a RNA/metabolismo
5.
Gastroenterology ; 165(5): 1219-1232, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37507075

RESUMO

BACKGROUND & AIMS: BiTE (bispecific T-cell engager) immune therapy has demonstrated clinical activity in multiple tumor indications, but its influence in the tumor microenvironment remains unclear. CLDN18.2 is overexpressed in solid tumors including gastric cancer (GC) and pancreatic ductal adenocarcinoma (PDAC), both of which are characterized by the presence of immunosuppressive cells, including regulatory T cells (Tregs) and few effector T cells (Teffs). METHODS: We evaluated the activity of AMG 910, a CLDN18.2-targeted half-life extended (HLE) BiTE molecule, in GC and PDAC preclinical models and cocultured Tregs and Teffs in the presence of CLDN18.2-HLE-BiTE. RESULTS: AMG 910 induced potent, specific cytotoxicity in GC and PDAC cell lines. In GSU and SNU-620 GC xenograft models, AMG 910 engaged human CD3+ T cells with tumor cells, resulting in significant antitumor activity. AMG 910 monotherapy, in combination with a programmed death-1 (PD-1) inhibitor, suppressed tumor growth and enhanced survival in an orthotopic Panc4.14 PDAC model. Moreover, Treg infusion enhanced the antitumor efficacy of AMG 910 in the Panc4.14 model. In syngeneic KPC models of PDAC, treatment with a mouse surrogate CLDN18.2-HLE-BiTE (muCLDN18.2-HLE-BiTE) or the combination with an anti-PD-1 antibody significantly inhibited tumor growth. Tregs isolated from mice bearing KPC tumors that were treated with muCLDN18.2-HLE-BiTE showed decreased T cell suppressive activity and enhanced Teff cytotoxic activity, associated with increased production of type I cytokines and expression of Teff gene signatures. CONCLUSIONS: Our data suggest that BiTE molecule treatment converts Treg function from immunosuppressive to immune enhancing, leading to antitumor activity in immunologically "cold" tumors.


Assuntos
Anticorpos Biespecíficos , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Animais , Camundongos , Linfócitos T Reguladores/metabolismo , Anticorpos Biespecíficos/genética , Anticorpos Biespecíficos/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Moléculas de Adesão Celular , Carcinoma Ductal Pancreático/tratamento farmacológico , Imunidade , Microambiente Tumoral , Claudinas
6.
Biochem Biophys Res Commun ; 704: 149661, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38417343

RESUMO

To date only four recombinant growth factors, including Filgrastim (rhG-CSF), have been approved by FDA as radiomitigators to ameliorate hematopoietic acute radiation syndrome (H-ARS). These approved agents are not stable under room-temperature, needing to be stored at 2-8 °C, and would not be feasible in a mass casualty scenario where rapid and cost-effective intervention is crucial. Delta-tocotrienol (δ-T3H), the most potent G-CSF-inducing agent among vitamin E isoforms, exhibited efficiency and selectivity on G-CSF production in comparison with TLR and STING agonists in mice. Five-dose δ-T3H was utilized as the optimal therapeutic regimen due to long-term G-CSF production and the best peripheral blood (PB) recovery of irradiated mice. Comparable with rhG-CSF, sequential administration of δ-T3H post-irradiation improved hematologic recovery and accelerated the regeneration of hematopoietic stem cells (HSCs) and hematopoietic progenitor cells (HPCs) in the bone marrow (BM) and spleen of 6.5Gy irradiated mice; and consistently enhanced repopulation of BM-HSCs. In 4.0Gy irradiated nonhuman primates, δ-T3H exhibited comparable efficacy as rhG-CSF to promote PB recovery and colony-formation of BM-HPCs. Altogether, we demonstrated that sequential administration of delta-tocotrienol ameliorates radiation-induced myelosuppression in mice and non-human primates through inducing G-CSF production, indicated δ-T3H as a promising radiomitigator for the management of H-ARS, particularly in a mass casualty scenario.


Assuntos
Medula Óssea , Células-Tronco Hematopoéticas , Vitamina E , Animais , Camundongos , Medula Óssea/patologia , Medula Óssea/efeitos da radiação , Fator Estimulador de Colônias de Granulócitos/efeitos dos fármacos , Fator Estimulador de Colônias de Granulócitos/metabolismo , Primatas , Proteínas Recombinantes/farmacologia , Vitamina E/análogos & derivados , Vitamina E/uso terapêutico
7.
J Transl Med ; 22(1): 422, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702814

RESUMO

BACKGROUND: Intrahepatic cholangiocarcinoma (ICC) is a highly malignant neoplasm and characterized by desmoplastic matrix. The heterogeneity and crosstalk of tumor microenvironment remain incompletely understood. METHODS: To address this gap, we performed Weighted Gene Co-expression Network Analysis (WGCNA) to identify and construct a cancer associated fibroblasts (CAFs) infiltration biomarker. We also depicted the intercellular communication network and important receptor-ligand complexes using the single-cell transcriptomics analysis of tumor and Adjacent normal tissue. RESULTS: Through the intersection of TCGA DEGs and WGCNA module genes, 784 differential genes related to CAFs infiltration were obtained. After a series of regression analyses, the CAFs score was generated by integrating the expressions of EVA1A, APBA2, LRRTM4, GOLGA8M, BPIFB2, and their corresponding coefficients. In the TCGA-CHOL, GSE89748, and 107,943 cohorts, the high CAFs score group showed unfavorable survival prognosis (p < 0.001, p = 0.0074, p = 0.028, respectively). Additionally, a series of drugs have been predicted to be more sensitive to the high-risk group (p < 0.05). Subsequent to dimension reduction and clustering, thirteen clusters were identified to construct the single-cell atlas. Cell-cell interaction analysis unveiled significant enhancement of signal transduction in tumor tissues, particularly from fibroblasts to malignant cells via diverse pathways. Moreover, SCENIC analysis indicated that HOXA5, WT1, and LHX2 are fibroblast specific motifs. CONCLUSIONS: This study reveals the key role of fibroblasts - oncocytes interaction in the remodeling of the immunosuppressive microenvironment in intrahepatic cholangiocarcinoma. Subsequently, it may trigger cascade activation of downstream signaling pathways such as PI3K-AKT and Notch in tumor, thus initiating tumorigenesis. Targeted drugs aimed at disrupting fibroblasts-tumor cell interaction, along with associated enrichment pathways, show potential in mitigating the immunosuppressive microenvironment that facilitates tumor progression.


Assuntos
Neoplasias dos Ductos Biliares , Fibroblastos Associados a Câncer , Colangiocarcinoma , Regulação Neoplásica da Expressão Gênica , Análise de Célula Única , Microambiente Tumoral , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Humanos , Microambiente Tumoral/genética , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Prognóstico , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Neoplasias dos Ductos Biliares/metabolismo , Transcriptoma/genética , Perfilação da Expressão Gênica , Redes Reguladoras de Genes , Comunicação Celular
8.
Ann Surg Oncol ; 31(1): 125-132, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37884700

RESUMO

BACKGROUND: Tumor necrosis has been indicated to correlate with dismal survival outcomes of a variety of solid tumors. However, the significance and prognostic value of tumor necrosis remain unclear in gallbladder carcinoma. The aim of this research is to explore the relationships between necrosis with long-term survival and tumor-related biological characteristics of patients with gallbladder carcinoma. PATIENTS AND METHODS: Patients with gallbladder carcinoma who accepted curative-intent resection in West China Hospital of Sichuan University (China) between January 2010 and December 2021 were retrospectively analyzed. Tumor necrosis was determined by staining the patient's original tissue sections with hematoxylin and eosin. Based on the presence of tumor necrosis, the pathologic features and survival outcomes were compared. RESULTS: This study enrolled 213 patients with gallbladder carcinoma who underwent curative-intent surgery, of whom 89 had tumor necrosis. Comparative analyses indicated that patients with tumor necrosis had more aggressive clinicopathological features, such as larger tumor size (p = 0.002), poorer tumor differentiation (p = 0.029), more frequent vascular invasion (p < 0.001), presence of lymph node metastasis (p = 0.014), and higher tumor status (p = 0.01), and experienced poorer survival. Univariate and multivariate analyses revealed that tumor necrosis was an independent prognostic factor for overall survival (multivariate: HR 1.651, p = 0.026) and disease-free survival (multivariate: HR 1.589, p = 0.040). CONCLUSIONS: Tumor necrosis can be considered as an independent predictive factor for overall survival and disease-free survival among individuals with gallbladder carcinoma, which was a valuable pathologic parameter.


Assuntos
Neoplasias da Vesícula Biliar , Humanos , Prognóstico , Neoplasias da Vesícula Biliar/patologia , Estudos Retrospectivos , Intervalo Livre de Doença , China , Estadiamento de Neoplasias
10.
Langenbecks Arch Surg ; 409(1): 51, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38305889

RESUMO

BACKGROUND: The neutrophil-lymphocyte ratio (NLR) and platelet distribution width (PDW) are associated with poor prognosis in various cancers. We aimed to analyze the prognostic value of the combination of preoperative NLR and PDW in patients with gallbladder carcinoma (GBC). METHODS: A total of 287 GBC patients who underwent curative-intent surgery in our institution was included. The relationship between NLR and PDW and clinicopathological features were analyzed. The receiver operating characteristic (ROC) curves were used to determine the optimal cutoff value for NLR and PDW. Overall survival (OS) was estimated using the Kaplan-Meier method. Meanwhile, the univariate and multivariate Cox regression models were used to assess the risk factors for OS. RESULTS: The optimal cutoff value of NLR and PDW was 3.00 and 14.76, respectively. In addition, survival analysis demonstrated that patients with NLR > 3.00 and PDW > 14.76 had a worse prognosis than patients with NLR ≤ 3.00 and PDW ≤ 14.76, respectively. The multivariate analysis showed that NLR and PDW were independent prognostic factors in the patients with GBC. When we combined NLR and PDW, the area under the ROC curve increased from 0.665 (NLR) and 0.632 (PDW) to 0.676. Moreover, the 1-, 3-, and 5-year OS of group A (patients with NLR ≤ 3.00 and PDW ≤ 14.76), group B (patients with either of NLR > 3.00 or PDW > 14.76) and group C (patients with NLR > 3.00 and PDW > 14.76) were 88.7%, 62.6%, 28.1%, 65.1%, 26.9%, 13.1%, and 34.8%, 8.3%, 0%, respectively. CONCLUSION: The combination of NLR and PDW may serve as a significant prognostic biomarker for GBC patients superior to either NLR or PDW alone.


Assuntos
Neoplasias da Vesícula Biliar , Neutrófilos , Humanos , Prognóstico , Estudos Retrospectivos , Linfócitos , Curva ROC
11.
Environ Toxicol ; 39(2): 952-964, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37975621

RESUMO

Di(2-ethylhexyl) phthalate (DEHP), an environmental endocrine disruptor, is one of the most common plasticizers and is widely used in various plastic products. DEHP induces apoptosis and oxidative stress and has been shown to have androgenic toxicity. However, the methods to combat DEHP-induced testicular damage and the mechanisms involved remain to be elucidated. In the present study, we used melatonin, which has strong antioxidant properties, to intervene in prepubertal mice and mouse Leydig cells (TM3) treated with DEHP or its metabolite mono(2-ethylhexyl) phthalate (MEHP). The results showed that melatonin protected against DEHP-induced testicular damage in prepubertal mice, mainly by protecting against DEHP-induced structural destruction of the germinal tubules and by attenuating the DEHP-induced decrease in testicular organ coefficients and testosterone levels. Transcriptomic analysis found that melatonin may attenuate DEHP-induced oxidative stress and apoptosis in prepubertal testes. In vitro studies further revealed that MEHP induces oxidative stress injury and increases apoptosis in TM3 cells, while melatonin reversed this damage. In vitro studies also found that MEHP exposure inhibited the expression levels of molecules related to the PI3K/AKT signaling pathway, and melatonin reversed this change. In conclusion, these findings suggest that melatonin protects against DEHP-induced prepubertal testicular injury via the PI3K/AKT signaling pathway, and provide a theoretical basis and experimental rationale for combating male reproductive dysfunction.


Assuntos
Dietilexilftalato , Melatonina , Masculino , Camundongos , Animais , Testículo , Melatonina/farmacologia , Dietilexilftalato/toxicidade , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Estresse Oxidativo , Apoptose
12.
Gastroenterology ; 163(5): 1267-1280.e7, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35718227

RESUMO

BACKGROUND & AIMS: The stroma in pancreatic ductal adenocarcinoma (PDAC) contributes to its immunosuppressive nature and therapeutic resistance. Herein we sought to modify signaling and enhance immunotherapy efficacy by targeting multiple stromal components through both intracellular and extracellular mechanisms. METHODS: A murine liver metastasis syngeneic model of PDAC was treated with focal adhesion kinase inhibitor (FAKi), anti-programmed cell death protein 1 (PD-1) antibody, and stromal hyaluronan (HA) degradation by PEGylated recombinant human hyaluronidase (PEGPH20) to assess immune and stromal modulating effects of these agents and their combinations. RESULTS: The results showed that HA degradation by PEGPH20 and reduction in phosphorylated FAK expression by FAKi leads to improved survival in PDAC-bearing mice treated with anti-PD-1 antibody. HA degradation in combination with FAKi and anti-PD-1 antibody increases T-cell infiltration and alters T-cell phenotype toward effector memory T cells. FAKi alters the expression of T-cell modulating cytokines and leads to changes in T-cell metabolism and increases in effector T-cell signatures. HA degradation in combination with anti-PD-1 antibody and FAKi treatments reduces granulocytes, including granulocytic- myeloid-derived suppressor cells and decreases C-X-C chemokine receptor type 4 (CXCR4)-expressing myeloid cells, particularly the CXCR4-expressing granulocytes. Anti-CXCR4 antibody combined with FAKi and anti-PD-1 antibody significantly decreases metastatic rates in the PDAC liver metastasis model. CONCLUSIONS: This represents the first preclinical study to identify synergistic effects of targeting both intracellular and extracellular components within the PDAC stroma and supports testing anti-CXCR4 antibody in combination with FAKi as a PDAC treatment strategy.


Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Hepáticas , Neoplasias Pancreáticas , Humanos , Camundongos , Animais , Neoplasias Pancreáticas/patologia , Adenocarcinoma/patologia , Hialuronoglucosaminidase/farmacologia , Hialuronoglucosaminidase/uso terapêutico , Ácido Hialurônico , Carcinoma Ductal Pancreático/genética , Neoplasias Hepáticas/tratamento farmacológico , Proteína-Tirosina Quinases de Adesão Focal , Citocinas/farmacologia , Morte Celular , Polietilenoglicóis/uso terapêutico , Microambiente Tumoral , Neoplasias Pancreáticas
13.
J Transl Med ; 21(1): 349, 2023 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-37237321

RESUMO

Gut microbiota is closely related to human health and disease because, together with their metabolites, gut microbiota maintain normal intestinal peristalsis. The use of antibiotics or opioid anesthetics, or both, during surgical procedures can lead to dysbiosis and affect intestinal motility; however, the underlying mechanisms are not fully known. This review aims to discuss the effect of gut microbiota and their metabolites on postoperative intestinal motility, focusing on regulating the enteric nervous system, 5-hydroxytryptamine neurotransmitter, and aryl hydrocarbon receptor.


Assuntos
Microbioma Gastrointestinal , Humanos , Intestinos/fisiologia , Motilidade Gastrointestinal , Disbiose
14.
J Org Chem ; 88(13): 8761-8769, 2023 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-37276259

RESUMO

The enantioselective synthesis of (+)-isolysergol was completed in 18 steps, and an overall yield of 11% was obtained from (2R)-(+)-phenyloxirane as a chiral pool. Key features of the synthesis include a stereoselective intramolecular 1,3-dipolar addition of nitrone with terminal olefin and a Cope elimination to furnish the D ring. A rhodium-catalyzed intramolecular [3 + 2] annulation of a benzene ring with α-imino carbenoid was designed to afford the 3,4-fused indole scaffold at the late stage of the synthesis.


Assuntos
Ergolinas , Catálise , Estrutura Molecular , Ciclização
15.
Phys Chem Chem Phys ; 25(23): 15756-15766, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37254560

RESUMO

As a new type of energetic material, cocrystal explosives demonstrate many excellent properties, such as high energy density and low sensitivity, due to the interaction between the molecules of the two components. The known decomposition temperature is 235 °C for CL-20/HMX cocrystals at a faster heating rate. CL-20 molecules could separate from the cocrystal matrix and decompose at a higher temperature, much lower than the decomposition temperature. The current work provided deep insight into the isothermal structural evolution of CL-20/HMX cocrystals with slow roasting at 190 °C. We found that the initial decomposition originates from separating CL-20 molecules from the surface along the (010) plane of the cocrystals. The gas products, such as NO2 and NO, escape from the largest exposed surface of the (010) plane and generates microbubbles and microholes. At the same time, the residual HMX molecules form δ-phase HMX crystals and shrink the volume by 72%. By increasing the time held at 190 °C, the decomposition of CL-20 molecules and recrystallization of the residual HMX molecules form a gully-like structure on the (010) plane of the CL-20/HMX cocrystal. After a long time at 190 °C, the CL-20 component completely decomposes, and all HMX molecules recrystallize in the δ-HMX form. The interaction between HMX and CL-20 molecules makes the decomposition rate of the CL-20/HMX cocrystal much slower than that of the CL-20 pure crystal with a similar decomposition activation energy during isothermal heating. This work can help to deeply understand the safety of CL-20/HMX cocrystal explosives at a temperature lower than the recognized decomposition temperature.

16.
Langenbecks Arch Surg ; 408(1): 382, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770780

RESUMO

BACKGROUND: The metastatic lymph node (LN) ratio (LNR) has shown to be an important prognostic factor in various gastrointestinal malignancies. Nevertheless, the prognostic significance of LNR in gallbladder carcinoma (GBC) remains to be determined. METHODS: From January 2007 to January 2018, 144 advanced GBC patients (T2-4 stages) who underwent curative surgery with at least 6 LNs retrieved were enrolled. Receiver operating characteristic (ROC) curve was performed to identify the optimal cut-off value for LNR. The clinicopathological features stratified by LNR level were analyzed. Meanwhile, univariate and multivariate Cox regression proportional hazard models were performed to identify risk factors for overall survival (OS). RESULTS: The optimal cut-off point for LNR was 0.28 according to the ROC curve. LNR>0.28 was associated with higher rate of D2 LN dissection (P=0.004) and higher tumor stages (P<0.001). Extent of liver resection, extrahepatic bile duct resection, tumor stage, LNR, margin status, tumor differentiation, and perineural invasion were associated with OS in univariate analysis (all P<0.05). GBC patients with LNR≤0.28 had a significantly longer median OS compared to those with LNR>0.28 (27.5 vs 18 months, P=0.004). Multivariate analysis indicated that tumor stage (T2 vs T3/T4; hazard ratio (HR) 1.596; 95% confidence interval (CI) 1.195-2.132), LNR (≤0.28 vs >0.28; HR 0.666; 95% CI 0.463-0.958), margin status (R0 vs R1; HR 1.828; 95% CI 1.148-2.910), and tumor differentiation (poorly vs well/moderately; HR 0.670; 95% CI 0.589-0.892) were independent prognostic factors for GBC (all P<0.05). CONCLUSIONS: LNR is correlated to advanced GBC prognosis and is a potential prognostic factor for advanced GBC with at least 6 LNs retrieved.


Assuntos
Carcinoma , Neoplasias da Vesícula Biliar , Humanos , Prognóstico , Razão entre Linfonodos , Estadiamento de Neoplasias , Linfonodos/patologia , Excisão de Linfonodo , Carcinoma/patologia , Estudos Retrospectivos
17.
Zhongguo Zhong Yao Za Zhi ; 48(9): 2343-2351, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37282863

RESUMO

This study explored the molecular mechanism of acteoside against hepatoma 22(H22) tumor in mice through c-Jun N-terminal kinase(JNK) signaling pathway. H22 cells were subcutaneously inoculated in 50 male BALB/c mice, and then the model mice were classified into model group, low-dose, medium-dose, and high-dose acteoside groups, and cisplatin group. The administration lasted 2 weeks for each group(5 consecutive days/week). The general conditions of mice in each group, such as mental status, diet intake, water intake, activity, and fur were observed. The body weight, tumor volume, tumor weight, and tumor-inhibiting rate were compared before and after administration. Morphological changes of liver cancer tissues were observed based on hematoxylin and eosin(HE) staining, and the expression of phosphorylated(p)-JNK, JNK, B-cell lymphoma-2(Bcl-2), Beclin-1, and light chain 3(LC3) in each tissue was detected by immunohistochemistry and Western blot. qRT-PCR was performed to detect the mRNA expression of JNK, Bcl-2, Beclin-1, and LC3. The general conditions of mice in model and low-dose acteoside groups were poor, while the general conditions of mice in the remaining three groups were improved. The body weight of mice in medium-dose acteoside group, high-dose acteoside group, and cisplatin group was smaller than that in model group(P<0.01). The tumor volume in model group was insignificantly different from that in low-dose acteoside group, and the volume in cisplatin group showed no significant difference from that in high-dose acteoside group. Tumor volume and weight in medium-dose and high-dose acteoside groups and cisplatin group were lower than those in the model group(P<0.001). The tumor-inhibiting rates were 10.72%, 40.32%, 53.79%, and 56.44% in the low-dose, medium-dose, and high-dose acteoside groups and cisplatin group, respectively. HE staining showed gradual decrease in the count of hepatoma cells and increasing sign of cell necrosis in the acteoside and cisplatin groups, and the necrosis was particularly obvious in the high-dose acteoside group and cisplatin group. Immunohistochemical results suggested that the expression of Beclin-1, LC3, p-JNK, and JNK was up-regulated in acteoside and cisplatin groups(P<0.05). The results of immunohistochemistry, Western blot, and qRT-PCR indicated that the expression of Bcl-2 was down-regulated in the medium-dose and high-dose acteoside groups and cisplatin group(P<0.01). Western blot showed that the expression of Beclin-1, LC3, and p-JNK was up-regulated in acteoside and cisplatin groups(P<0.01), and there was no difference in the expression of JNK among groups. qRT-PCR results showed that the levels of Beclin-1 and LC3 mRNA were up-regulated in the acteoside and cisplatin groups(P<0.05), and the level of JNK mRNA was up-regulated in medium-dose and high-dose acteoside groups and cisplatin group(P<0.001). Acteoside promotes apoptosis and autophagy of H22 cells in mice hepatoma cells by up-regulating the JNK signaling pathway, thus inhibiting tumor growth.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Masculino , Animais , Camundongos , Cisplatino/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/genética , Sistema de Sinalização das MAP Quinases , Proteína Beclina-1 , Apoptose , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/genética , Necrose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Linhagem Celular Tumoral , RNA Mensageiro/metabolismo , Autofagia
18.
Small ; 18(22): e2200824, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35523735

RESUMO

Constructing high-order DNA nano-architectures in large sizes is of critical significance for the application of DNA nanotechnology. Robust and flexible design strategies together with easy protocols to construct high-order large-size DNA nano-architectures remain highly desirable. In this work, the authors report a simple and versatile one-pot strategy to fabricate DNA architectures with the assistance of spherical gold nanoparticles modified with thiolated oligonucleotide strands (SH-DNA-AuNPs), which serve as "power strips" to connect various DNA nanostructures carrying complementary ssDNA strands as "plugs". By modulating the plug numbers and positions on each DNA nanostructure and the ratios between DNA nanostructures and AuNPs, the desired architectures are formed via the stochastic co-assembly of different modules. This SH-DNA-AuNP-mediated plug-in assembly (SAMPA) strategy offers new opportunities to drive macroscopic self-assembly to meet the demand of the fabrication of well-defined nanomaterials and nanodevices.


Assuntos
Nanopartículas Metálicas , Nanoestruturas , DNA/química , Ouro/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Nanotecnologia/métodos
19.
Inorg Chem ; 61(39): 15408-15415, 2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36126270

RESUMO

For the famous functional REF3 family, there exist two typical structures, that is, orthorhombic phase and hexagonal phase. In the present work, high pressure behaviors of the orthorhombic phase REF3 (RE = Sm to Lu and Y) were investigated by experimental methods and first-principles calculations. The pressure-induced phase transitions of GdF3, TbF3, YbF3, and LuF3 were studied by using in situ photoluminescence measurements in the diamond anvil cell. At room temperature, all these four compounds follow the phase transition route from orthorhombic to hexagonal phase at 5.5-20.6 GPa. The pressure ranges of phase transition are 5.5-9.3, 8.4-11.9, 13.5-20.3, and 14.8-20.6 GPa for GdF3, TbF3, YbF3, and LuF3, respectively. In combination with first-principles calculations, we infer that all orthorhombic REF3 members from Sm-Lu and Y obey the same orthorhombic-to-hexagonal phase transition rules under high pressures. For lanthanide trifluorides, the transition pressures increase as zero pressure volumes of REF3 in the orthorhombic phase become smaller. As the calculation results show, this is because the difference in value of energy from the two structures is larger. This work not only provides precise structural change but also benefits the understanding of two typical structures for rare-earth trifluorides, which may play a significant role in the applications of REF3.

20.
Phys Chem Chem Phys ; 24(4): 2396-2402, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35019913

RESUMO

Thermal mechanical responses under high temperature and high pressure are basic information to understand the performance of energetic materials. In this work, the pressure effects on the thermal decay of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) are explored. Up to the initial pressure of 4.6 GPa, the pressure dependent decomposition boundary is built and no phase transition occurs until the decomposition of the LLM-105 crystal. The decomposition temperature is significantly lifted via a weak loading pressure. The experimental measurement confirms the decomposition products, including NO2, CO2 and NH3, which are predicted by the density functional tight-binding molecular dynamics method. The calculation described the details of thermal decay in the initial stages under high pressure. The sudden drop in the shifts of the Raman modes associated with hydrogen bonds under high pressure indicates the strengthening of the intermolecular hydrogen bonds and the occurrence of intermolecular hydrogen transfer prior to crystal decomposition. The simulation supported the existence of intermolecular hydrogen transfer and provided the transfer path and decomposition mechanism. All of these jobs not only contribute significantly to the understanding of thermal decomposition of energetic materials as a function of pressure, but also contribute to the understanding of sensitivity mechanisms and safety issues.

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