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1.
Brain ; 147(2): 566-589, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37776513

RESUMO

Cerebral malaria is the deadliest complication that can arise from Plasmodium infection. CD8 T-cell engagement of brain vasculature is a putative mechanism of neuropathology in cerebral malaria. To define contributions of brain endothelial cell major histocompatibility complex (MHC) class I antigen-presentation to CD8 T cells in establishing cerebral malaria pathology, we developed novel H-2Kb LoxP and H-2Db LoxP mice crossed with Cdh5-Cre mice to achieve targeted deletion of discrete class I molecules, specifically from brain endothelium. This strategy allowed us to avoid off-target effects on iron homeostasis and class I-like molecules, which are known to perturb Plasmodium infection. This is the first endothelial-specific ablation of individual class-I molecules enabling us to interrogate these molecular interactions. In these studies, we interrogated human and mouse transcriptomics data to compare antigen presentation capacity during cerebral malaria. Using the Plasmodium berghei ANKA model of experimental cerebral malaria (ECM), we observed that H-2Kb and H-2Db class I molecules regulate distinct patterns of disease onset, CD8 T-cell infiltration, targeted cell death and regional blood-brain barrier disruption. Strikingly, ablation of either molecule from brain endothelial cells resulted in reduced CD8 T-cell activation, attenuated T-cell interaction with brain vasculature, lessened targeted cell death, preserved blood-brain barrier integrity and prevention of ECM and the death of the animal. We were able to show that these events were brain-specific through the use of parabiosis and created the novel technique of dual small animal MRI to simultaneously scan conjoined parabionts during infection. These data demonstrate that interactions of CD8 T cells with discrete MHC class I molecules on brain endothelium differentially regulate development of ECM neuropathology. Therefore, targeting MHC class I interactions therapeutically may hold potential for treatment of cases of severe malaria.


Assuntos
Malária Cerebral , Camundongos , Humanos , Animais , Malária Cerebral/patologia , Malária Cerebral/prevenção & controle , Células Endoteliais/patologia , Encéfalo/patologia , Barreira Hematoencefálica/patologia , Linfócitos T CD8-Positivos , Endotélio/patologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças
2.
J Am Chem Soc ; 146(21): 14889-14897, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38747066

RESUMO

Ni-rich cathodes are some of the most promising candidates for advanced lithium-ion batteries, but their available capacities have been stagnant due to the intrinsic Li+ storage sites. Extending the voltage window down can induce the phase transition from O3 to 1T of LiNiO2-derived cathodes to accommodate excess Li+ and dramatically increase the capacity. By setting the discharge cutoff voltage of LiNi0.6Co0.2Mn0.2O2 to 1.4 V, we can reach an extremely high capacity of 393 mAh g-1 and an energy density of 1070 Wh kg-1 here. However, the phase transition causes fast capacity decay and related structural evolution is rarely understood, hindering the utilization of this feature. We find that the overlithiated phase transition is self-limiting, which will transform into solid-solution reaction with cycling and make the cathode degradation slow down. This is attributed to the migration of abundant transition metal ions into lithium layers induced by the overlithiation, allowing the intercalation of overstoichiometric Li+ into the crystal without the O3 framework change. Based on this, the wide-potential cycling stability is further improved via a facile charge-discharge protocol. This work provides deep insight into the overstoichiometric Li+ storage behaviors in conventional layered cathodes and opens a new avenue toward high-energy batteries.

3.
Small ; 20(5): e2304452, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37752683

RESUMO

Carbon-based hole transport layer-free perovskite solar cells (PSCs) based on methylammonium lead triiodide (MAPbI3 ) have become one of the research focus due to low cost, easy preparation, and good optoelectronic properties. However, instability of perovskite under vacancy defects and stress-strain makes it difficult to achieve high-efficiency and stable power output. Here, a soft-structured long-chain 2D pentanamine iodide (abbreviated as "PI") is used to improve perovskite quality and interfacial mechanical compatibility. PI containing CH3 (CH2 )4 NH3 + and I- ions not only passivate defects at grain boundaries, but also effectively alleviate residual stress during high temperature annealing via decreasing Young's modulus of perovskite film. Most importantly, PI effectively increases matching degree of Young's modulus between MAPbI3 (47.1 GPa) and carbon (6.7 GPa), and strengthens adhesive fracture energy (Gc ) between perovskite and carbon, which is helpful for outward release of nascent interfacial stress generated under service conditions. Consequently, photoelectric conversion efficiency (PCE) of optimal device is enhanced from 10.85% to 13.76% and operational stability is also significantly improved. 83.1% output is maintained after aging for 720 h at room temperature and 25-60% relative humidity (RH). This strategy of regulation from chemistry and physics provides a strategy for efficient and stable carbon-based PSCs.

4.
BMC Cancer ; 24(1): 904, 2024 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-39068410

RESUMO

The lncRNA NEAT1 has been shown to promote the progression of several cancers, containing laryngeal squamous cell carcinoma (LSCC). However, the precise mechanism by which it promotes LSCC progression remains unclear. In this study, we verified the high expression of lncRNA NEAT1 in LSCC tissues and cells using RT-qPCR. Analysis of clinical data exhibited that high expression of lncRNA NEAT1 was associated with a history of smoking, worse T stage, lymph node metastasis, and later TNM stage in patients with LSCC. The promotion effect of lncRNA NEAT1 on LSCC cell proliferation, migration, invasion, and tumor growth in vivo was verified by CCK-8, plate clone formation, Transwell, and nude mouse tumorigenicity assays. Bioinformatics prediction and double luciferase reporter gene assay verified the binding of miR-411-3p to lncRNA NEAT1 and FZD3 mRNA, and inhibition of miR-411-3p reversed the inhibitory effect of lncRNA NEAT1 on FZD3 expression in LSCC cells. We also verified that lncRNA NEAT1-mediated FZD3 activation in the Wnt pathway affects LSCC development. In conclusion, we demonstrate that lncRNA NEAT1 promotes the progression of LSCC, and propose that the lncRNA NEAT1/miR-411-3p/FZD3 axis may be an effective target for LSCC therapy.


Assuntos
Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Neoplasias Laríngeas , MicroRNAs , RNA Longo não Codificante , Via de Sinalização Wnt , Humanos , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Neoplasias Laríngeas/genética , Neoplasias Laríngeas/patologia , Neoplasias Laríngeas/metabolismo , Via de Sinalização Wnt/genética , Proliferação de Células/genética , Movimento Celular/genética , Animais , Camundongos , Masculino , Feminino , Linhagem Celular Tumoral , Invasividade Neoplásica/genética , Receptores Frizzled/genética , Receptores Frizzled/metabolismo , Camundongos Nus , Pessoa de Meia-Idade , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/genética , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo
5.
Cell Biol Int ; 48(1): 31-45, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37655528

RESUMO

Arachidonic acid metabolism plays a crucial role in the development and progression of inflammatory and metabolic liver diseases. However, its role in hepatocellular carcinoma (HCC) remains unclear. In this study, we investigated the expression of key genes involved in the arachidonic acid metabolism pathway in HCC using a combination of bioinformatics, proteomics and immunohistochemistry analyses. Through a comprehensive analysis of publicly available datasets, clinical HCC tissues, and tissue microarrays, we compared the expression of hepatic arachidonic acid metabolic genes. We observed significant downregulation of cytochrome P450 (CYP450) pathway genes at both the messenger RNA and protein levels in HCC tissues compared to normal liver tissues. Furthermore, we observed a strong correlation between the deregulation of the arachidonic acid metabolism CYP450 pathway and the pathological features and prognosis of HCC. Specifically, the expression of CYP2C8/9/18/19 was significantly correlated with pathological grade (r = -.484, p < .0001), vascular invasion (r = -.402, p < .0001), aspartate transaminase (r = -.246, p = .025), gamma-glutamyl transpeptidase (r = -.252, p = .022), alkaline phosphatase (r = -.342, p = .002), alpha-fetoprotein (r = -.311, p = .004) and carbohydrate antigen 19-9 (r = -.227, p = .047). Moreover, we discovered a significant association between CYP450 pathway activity and vascular invasion in HCC. Collectively, these data indicate that arachidonic acid CYP450 metabolic pathway deregulation is implicated in HCC progression and may be a potential predictive factor for early recurrence in patients with HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/metabolismo , Neoplasias Hepáticas/metabolismo , Ácido Araquidônico , Sistema Enzimático do Citocromo P-450/genética
6.
J Craniofac Surg ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38252538

RESUMO

PURPOSE: To investigate the clinical manifestations, imaging, pathology, and prognosis of orbital solitary fibrous tumors (OSFTs). In addition, the surgical incisions and the treatment outcomes were also evaluated. METHODS: A total of 89 patients with pathologically confirmed primary OSFTs were enrolled onto this study. Clinical and histopathological characteristics, imaging data, treatment modalities, and follow-up time, including tumor recurrence and death, were documented. The outcome measures included overall survival and disease-free survival time. RESULTS: Among 89 eligible cases, the median age of presentation was 39 years (range: 5-80 years) at the initial diagnosis. The most common presenting symptom was painless proptosis (54, 60.67%), then palpable mass (31, 34.83%), swelling (29, 32.58%), and impaired ocular motility (27, 30.34%). Tumor-related severe impaired vision was found in 11 patients (12.36%), including no-light-perception blindness (6, 6.74%), light-perception (2, 2.25%), and hand-movement (1, 1.12%). The preoperative imaging (computed tomography and magnetic resonance imaging) accurate diagnostic rate of OSFTs was 17.98% (16, 95% CI: 0.098-0.261), and misdiagnosis rate was 25.84% (23, 95% CI: 0.166-0.351). Grossly intact masses were excised for 27 patients (30.34%). Among the 89 patients, 33 (37.08%) were recurrences, and the median of these recurrent patients' interval between the first and the last operation was 7.33 years (range: 0.12-29.69 years). In 81 patients with complete follow-up data, the median course of the disease was 9.64 years (range: 1.55-33.65 years) from the onset OSFT. The overall survival rate of the 81 patients was 93.83% with a median course of 8.48 years (range: 0.38-30.4 years) from diagnosis of OSFT, and the disease-free survival rate of 81 patients was 91.36% with a median follow-up of 4.76 years (range: 0.08-19.22 years) after the last surgery. Of all the 81 patients, 5 patients (6.17%) developed local recurrence, and 3 patients (3.70%) died from tumor-related diseases, including pulmonary metastasis (2, 2.47%) and complications from intracranial lesions (1, 1.23%). Ten patients (11.24%) received postoperational radiation therapy, including 125I seeds implantation (5, 6.17%) and external beam radiotherapy (5, 6.17%), and remained no recurrence. CONCLUSIONS: In this series, OSFTs showed long courses and easy recurrence. Although it was very important to choose a proper surgical incision for intact resection of OSFTs at the initial surgery to avoiding recurrence, preoperative imaging is of very limited use since it is not able to identify OSFTs effectively. Postoperative radiotherapy may be beneficial to reduce the recurrence of OSFTs with malignant pathologic features.

7.
Nano Lett ; 23(21): 9900-9906, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37862605

RESUMO

Scanning near-field optical microscope (SNOM) with nanoscale spatial resolution has been a powerful tool in studying the plasmonic properties of nano materials/structures. However, the quantification of the SNOM measurement remains a major challenge in the field due to the lack of reliable methodologies. We employed the point-dipole model to describe the tip-surface interaction upon laser illumination and theoretically derived the quantitative relationship between the measured results and the actual near-field electric field strength. Thus, we can experimentally reconstruct the near-field electric field through this theoretically calculated relationship. We also developed an experimental technique together with FEM simulation to get the above relationship experimentally and reconstruct the near-field electric field from the measurement by SNOM.

8.
Cancer ; 129(13): 2013-2022, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-36951498

RESUMO

BACKGROUND: Minimal residual disease (MRD) is an important prognostic factor for survival in adults with acute leukemia. The role of pretransplantation MRD status in myelodysplastic syndrome with excess blasts (MDS-EB) is unknown. This study retrospectively analyzed the relationship between pretransplantation MRD status and long-term survival. MATERIALS AND METHODS: Patients with MDS-EB who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) from March 5, 2005, to November 8, 2020, were included. The relationship between pretransplantation MRD status and long-term survival was analyzed using univariate and multivariate logistic regression models. RESULTS: Of 220 patients with MDS-EB who underwent allo-HSCT, 198 were eligible for inclusion in this multicenter, retrospective cohort study. Complete remission was attained in 121 (61.1%) patients, and 103 patients underwent detection of MRD pretransplantation, with 67 patients being MRD-positive and 36 patients being MRD-negative. The median follow-up time was 16 months, the median age was 41 years (6-65 years), and 58% of the patients were men. The 3-year disease-free survival (DFS) and overall survival (OS) probabilities for all patients were 70.1% and 72.9%, respectively. For patients in complete remission, the 3-year DFS and OS probabilities were 72.2% and 74.8%, respectively. Further analysis found that the 3-year DFS rates of MRD-negative and MRD-positive patients were 85.6% and 66.5% (p = .045), respectively, whereas the 3-year OS rates were 91.3% and 66.4% (p = .035), respectively. Univariate and multivariate analyses showed that poor pretransplantation MRD clearance was an independent prognostic risk factor for DFS and OS. CONCLUSION: Poor pretransplantation MRD clearance is an independent prognostic risk factor for long-term survival after allo-HSCT for patients with MDS-EB. PLAIN LANGUAGE SUMMARY: Poor minimal residual disease clearance pretransplanation is an independent prognostic risk factor for long-term survival after allogeneic hematopoietic stem cell transplantation for patients with myelodysplastic syndrome with excess blasts.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Adulto , Masculino , Humanos , Feminino , Prognóstico , Estudos Retrospectivos , Neoplasia Residual/diagnóstico , Síndromes Mielodisplásicas/terapia , Fatores de Risco
9.
Small ; 19(21): e2300175, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36843265

RESUMO

The construction of a protective layer for stabilizing anion redox reaction is the key to obtaining long cycling stability for Li-rich Mn-based cathode materials. However, the protection of the exposed surface/interface of the primary particles inside the secondary particles is usually ignored and difficult, let alone the investigation of the impact of the surface engineering of the internal primary particles on the cycling stability. In this work, an efficient method to regulate cycling stability is proposed by simply adjusting the distribution state of the boron nickel complexes coating layer. Theoretical calculation and experimental results display that the full-surface boron nickel complexes coating layer can not only passivate the activity of interface oxygen and improve its stability but also play the role of sharing voltage and protective layer to gradually activate the oxygen redox reaction during cycling. As a result, the elaborately designed cobalt-free Li-rich Mn-based cathode displays the highest discharge-specific capacity retentions of 91.1% after 400 cycles at 1 C and 94.3% even after 800 cycles at 5 C. In particular, the regulation strategy has well universality and is suitable for other high-capacity Li-rich cathode materials.

10.
Hepatology ; 75(2): 338-352, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34455616

RESUMO

BACKGROUND AND AIMS: Hepatic ischemia-reperfusion injury (IRI) is a common complication of hepatectomy and liver transplantation. However, the mechanisms underlying hepatic IRI have not been fully elucidated. Regulator of G-protein signaling 14 (RGS14) is a multifunctional scaffolding protein that integrates the G-protein and mitogen-activated protein kinase (MAPK) signaling pathways. However, the role of RGS14 in hepatic IRI remains unclear. APPROACH AND RESULTS: We found that RGS14 expression increased in mice subjected to hepatic ischemia-reperfusion (IR) surgery and during hypoxia reoxygenation in hepatocytes. We constructed global RGS14 knockout (RGS14-KO) and hepatocyte-specific RGS14 transgenic (RGS14-TG) mice to establish 70% hepatic IRI models. Histological hematoxylin and eosin staining, levels of alanine aminotransferase and aspartate aminotransferase, expression of inflammatory factors, and apoptosis were used to assess liver damage and function in these models. We found that RGS14 deficiency significantly aggravated IR-induced liver injury and activated hepatic inflammatory responses and apoptosis in vivo and in vitro. Conversely, RGS14 overexpression exerted the opposite effect of the RGS14-deficient models. Phosphorylation of TGF-ß-activated kinase 1 (TAK1) and its downstream effectors c-Jun N-terminal kinase (JNK) and p38 increased in the liver tissues of RGS14-KO mice but was repressed in those of RGS14-TG mice. Furthermore, inhibition of TAK1 phosphorylation rescued the effect of RGS14 deficiency on JNK and p38 activation, thus blocking the inflammatory responses and apoptosis. CONCLUSIONS: RGS14 plays a protective role in hepatic IR by inhibiting activation of the TAK1-JNK/p38 signaling pathway. This may be a potential therapeutic strategy for reducing incidences of hepatic IRI in the future.


Assuntos
MAP Quinase Quinase Quinases/metabolismo , Proteínas RGS/genética , Proteínas RGS/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Alanina Transaminase/metabolismo , Animais , Apoptose , Aspartato Aminotransferases/metabolismo , Hipóxia Celular , Células Cultivadas , Ativação Enzimática , Hepatócitos/metabolismo , Inflamação/genética , Inflamação/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Fígado/metabolismo , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Fosforilação , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
11.
Hepatology ; 76(1): 94-111, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-34735734

RESUMO

BACKGROUND AND AIMS: Hepatic ischemia-reperfusion (HIR) injury, a common clinical complication of liver transplantation and resection, affects patient prognosis. Ring finger protein 5 (RNF5) is an E3 ubiquitin ligase that plays important roles in endoplasmic reticulum stress, unfolded protein reactions, and inflammatory responses; however, its role in HIR is unclear. APPROACH AND RESULTS: RNF5 expression was significantly down-regulated during HIR in mice and hepatocytes. Subsequently, RNF5 knockdown and overexpression of cell lines were subjected to hypoxia-reoxygenation challenge. Results showed that RNF5 knockdown significantly increased hepatocyte inflammation and apoptosis, whereas RNF5 overexpression had the opposite effect. Furthermore, hepatocyte-specific RNF5 knockout and transgenic mice were established and subjected to HIR, and RNF5 deficiency markedly aggravated liver damage and cell apoptosis and activated hepatic inflammatory responses, whereas hepatic RNF5 transgenic mice had the opposite effect compared with RNF5 knockout mice. Mechanistically, RNF5 interacted with phosphoglycerate mutase family member 5 (PGAM5) and mediated the degradation of PGAM5 through K48-linked ubiquitination, thereby inhibiting the activation of apoptosis-regulating kinase 1 (ASK1) and its downstream c-Jun N-terminal kinase (JNK)/p38. This eventually suppresses the inflammatory response and cell apoptosis in HIR. CONCLUSIONS: We revealed that RNF5 protected against HIR through its interaction with PGAM5 to inhibit the activation of ASK1 and the downstream JNK/p38 signaling cascade. Our findings indicate that the RNF5-PGAM5 axis may be a promising therapeutic target for HIR.


Assuntos
Proteínas de Membrana , Fosfoproteínas Fosfatases , Traumatismo por Reperfusão , Ubiquitina-Proteína Ligases , Animais , Apoptose , Humanos , Fígado/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , Fosfoproteínas Fosfatases/metabolismo , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
12.
Cell Commun Signal ; 21(1): 167, 2023 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-37386564

RESUMO

BACKGROUND: Immunogenic cell death (ICD), which releases danger-associated molecular patterns (DAMP) that induce potent anticancer immune response, has emerged as a key component of therapy-induced anti-tumor immunity. The aim of this work was to analyze whether the carbonic anhydrase IX inhibitor S4 can elicit ICD in glioma cells. METHODS: The effects of S4 on glioma cell growth were evaluated using the CCK-8, clonogenic and sphere assays. Glioma cell apoptosis was determined by flow cytometry. Surface-exposed calreticulin (CRT) was inspected by confocal imaging. The supernatants of S4-treated cells were concentrated for the determination of HMGB1and HSP70/90 expression by immunoblotting. RNA-seq was performed to compare gene expression profiles between S4-treated and control cells. Pharmacological inhibition of apoptosis, autophagy, necroptosis and endoplasmic reticulum (ER) stress was achieved by inhibitors. In vivo effects of S4 were evaluated in glioma xenografts. Immunohistochemistry (IHC) was performed to stain Ki67 and CRT. RESULTS: S4 significantly decreased the viability of glioma cells and induced apoptosis and autophagy. Moreover, S4 triggered CRT exposure and the release of HMGB1 and HSP70/90. Inhibition of either apoptosis or autophagy significantly reversed S4-induced release of DAMP molecules. RNA-seq analysis indicated that the ER stress pathway was deregulated upon exposure to S4. Both PERK-eIF2α and IRE1α- XBP1 axes were activated in S4-treated cells. Furthermore, pharmacological inhibition of PERK significantly suppressed S4-triggered ICD markers and autophagy. In glioma xenografts, S4 significantly reduced tumor growth. CONCLUSIONS: Altogether, these findings suggest S4 as a novel ICD inducer in glioma and might have implications for S4-based immunotherapy. Video Abstract.


Assuntos
Endorribonucleases , Glioma , Humanos , Anidrase Carbônica IX , Morte Celular Imunogênica , Proteínas Serina-Treonina Quinases
13.
Analyst ; 148(3): 507-511, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36594781

RESUMO

Here, hydrophilic carbon dots (H-CDs) are prepared by a facile room temperature method. The strength of hydrogen bonds can be controlled by introducing proton and aprotic solvents, respectively, so as to realize the tunable aggregation state of H-CDs. Because of the ultrasensitive response to dimethyl sulfoxide (DMSO), H-CDs can serve as optical probes for detecting DMSO in a linear range of 0.005% to 0.75% and with a detection limit of 0.001%.

14.
Magn Reson Chem ; 61(6): 386-391, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36929032

RESUMO

Two new sesquiterpenoids, dendroaduoid A (1) and dendroaduol (2), together with four known sesquiterpenoids were isolated from the stems of Dendrobium aduncum. Their structures were identified by HR-ESI-MS and NMR experiments, and the complete assignments of 1 H and 13 C NMR data for two new sesquiterpenoids were obtained by the aid of HSQC, HMBC, 1 H-1 H COSY, NOESY, and ECD techniques. The cytotoxic effects of the isolated compounds on four tumor cell lines (HCT-116, HepG2, A549, and SW1990) were evaluated using MTT assay. Otherwise, the inhibitory activity of these six sesquiterpenoids on glycosidase was also evaluated.


Assuntos
Dendrobium , Sesquiterpenos , Linhagem Celular Tumoral , Sesquiterpenos/farmacologia
15.
Magn Reson Chem ; 61(8): 481-486, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37227105

RESUMO

Six lactone derivatives, including four α-pyrones derivatives (1-4), two α-furanone derivatives (5 and 6), were isolated from the Dendrobium pendulum. Structural elucidation of these undescribed lactone derivatives were accomplished on the basis of detailed nuclear magnetic resonance analysis, and the absolute configurations of compounds 1-4 were confirmed by electronic circular dichroism (ECD) techniques. The cytotoxic effects of isolated compounds on human breast cancer cell MDA-MB-231 were evaluated by the MTT assay.


Assuntos
Antineoplásicos , Dendrobium , Humanos , Estrutura Molecular , Lactonas/farmacologia , Lactonas/química , Dendrobium/química , Espectroscopia de Ressonância Magnética
16.
J Craniofac Surg ; 34(2): e115-e120, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36123763

RESUMO

PURPOSE: To report management of a series of patients with primary malignant lacrimal sac tumors and to compare these results to the previously published literature. MATERIALS AND METHODS: A total of 27 patients with pathologically confirmed primary malignant lacrimal sac lesions were enrolled into this study. Pathological classifications, clinical characteristics, various treatment modalities and follow-up time, including tumor recurrence, were documented. The outcome measures included overall survival, progression-free survival, and median survival time. RESULTS: Among 27 eligible cases, 33.33% (9/27) of the tumor was non-Hodgkin B-cell lymphoma, and 33.33% (9/27) was squamous cell carcinoma; both were the most common tumor in this series, followed by adenocarcinoma 18.52% (5/27), then melanoma 7.41% (2/27). Treatment modalities included surgery, radiotherapy, and/or chemotherapy, the overall survival rate of 27 patients was 70.37%, with a median follow-up of 45 months (range: 7 mo-16 y), 8 patients had died from metastatic disease, but 13 patients remained without evidence of recurrent tumor. The 5-year overall survival and progression-free survival for all cases were 73.33% and 66.67%, respectively. The median survival time for 5 deceased patients with interstitial brachytherapy was 98 months, and 5-year survival rate was 60%. CONCLUSIONS: In this series, among primary malignant lacrimal sac tumors, the proportion of lymphoma had increased when compared with the previously published literature, and multidisciplinary therapy may lead to a good prognosis in the majority of patients with the tumors and patients may benefit more from interstitial brachytherapy than external beam radiotherapy.


Assuntos
Adenocarcinoma , Neoplasias Oculares , Doenças do Aparelho Lacrimal , Ducto Nasolacrimal , Humanos , Ducto Nasolacrimal/patologia , Doenças do Aparelho Lacrimal/patologia , Neoplasias Oculares/patologia , Recidiva Local de Neoplasia/patologia , Adenocarcinoma/patologia
17.
Angew Chem Int Ed Engl ; 62(22): e202302170, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37002861

RESUMO

Layered transition metal oxide cathodes have been one of the dominant cathodes for lithium-ion batteries with efficient Li+ intercalation chemistry. However, limited by the weak layered interaction and unstable surface, mechanical and chemical failure plagues their electrochemical performance, especially for Ni-rich cathodes. Here, adopting a simultaneous elemental-structural atomic arrangement control based on the intrinsic Ni-Co-Mn system, the surface role is intensively investigated. Within the invariant oxygen sublattice of the crystal, a robust surface with the synergistic concentration gradient and layered-spinel intertwined structure is constructed on the model single-crystalline Ni-rich cathode. With mechanical strain dissipation and chemical erosion suppression, the cathode exhibits an impressive capacity retention of 82 % even at the harsh 60 °C after 150 cycles at 1 C. This work highlights the coupling effect of structure and composition on the chemical-mechanical properties, and the concept will spur more researches on the cathodes that share the same sublattice.

18.
Angew Chem Int Ed Engl ; 62(16): e202300384, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-36840689

RESUMO

In overcoming the Li+ desolvation barrier for low-temperature battery operation, a weakly-solvated electrolyte based on carboxylate solvent has shown promises. In case of an organic-anion-enriched primary solvation sheath (PSS), we found that the electrolyte tends to form a highly swollen, unstable solid electrolyte interphase (SEI) that shows a high permeability to the electrolyte components, accounting for quickly declined electrochemical performance of graphite-based anode. Here we proposed a facile strategy to tune the swelling property of SEI by introducing an inorganic anion switch into the PSS, via LiDFP co-solute method. By forming a low-swelling, Li3 PO4 -rich SEI, the electrolyte-consuming parasitic reactions and solvent co-intercalation at graphite-electrolyte interface are suppressed, which contributes to efficient Li+ transport, reversible Li+ (de)intercalation and stable structural evolution of graphite anode in high-energy Li-ion batteries at a low temperature of -20 °C.

19.
J Am Chem Soc ; 144(25): 11338-11347, 2022 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-35700279

RESUMO

Single-crystalline Ni-rich cathodes with high capacity have drawn much attention for mitigating cycling and safety crisis of their polycrystalline analogues. However, planar gliding and intragranular cracking tend to occur in single crystals with cycling, which undermine cathode integrity and therefore cause capacity degradation. Herein, we intensively investigate the origin and evolution of the gliding phenomenon in single-crystalline Ni-rich cathodes. Discrete or continuous gliding forms are revealed with new surface exposure including the gliding plane (003) and reconstructed (-108) under surface energy drive. It is also demonstrated that the gliding process is the in-plane migration of transition metal ions, and reducing oxygen vacancies will increase the migration energy barrier by which gliding and microcracking can be restrained. The designed cathode with less oxygen deficiency exhibits outstanding cycling performance with an 80.8% capacity retention after 1000 cycles in pouch cells. Our findings provide an insight into the relationship between defect control and chemomechanical properties of single-crystalline Ni-rich cathodes.

20.
Anal Chem ; 94(6): 2882-2890, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35112843

RESUMO

The endoplasmic reticulum (ER) is crucial for the regulation of multiple cellular processes, such as cellular responses to stress and protein synthesis, folding, and posttranslational modification. Nevertheless, monitoring ER physiological activity remains challenging due to the lack of powerful detection methods. Herein, we built a two-stage cascade recognition process to achieve dynamic visualization of ER stress in living cells based on a fluorescent carbon dot (CD) probe, which is synthesized by a facile one-pot hydrothermal method without additional modification. The fluorescent CD probe enables two-stage cascade ER recognition by first accumulating in the ER as the positively charged and lipophilic surface of the CD probe allows its fast crossing of multiple membrane barriers. Next, the CD probe can specifically anchor on the ER membrane via recognition between boronic acids and o-dihydroxy groups of mannose in the ER lumen. The two-stage cascade recognition process significantly increases the ER affinity of the CD probe, thus allowing the following evaluation of ER stress by tracking autophagy-induced mannose transfer from the ER to the cytoplasm. Thus, the boronic acid-functionalized cationic CD probe represents an attractive tool for targeted ER imaging and dynamic tracking of ER stress in living cells.


Assuntos
Estresse do Retículo Endoplasmático , Retículo Endoplasmático , Autofagia , Retículo Endoplasmático/metabolismo , Corantes Fluorescentes/metabolismo
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