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1.
Nano Lett ; 24(18): 5498-5505, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38619556

RESUMO

Revealing low-dimensional material growth dynamics is critical for crystal growth engineering. However, in a practical high-temperature growth system, the crystal growth process is a black box because of the lack of heat-resistant imaging tools. Here, we develop a heat-resistant optical microscope and embed it in a chemical vapor deposition (CVD) system to investigate two-dimensional (2D) crystal growth dynamics. This in situ optical imaging CVD system can tolerate temperatures of ≤900 °C with a spatial resolution of ∼1 µm. The growth of monolayer MoS2 crystals was studied as a model for 2D crystal growth. The nucleation and growth process have been imaged. Model analysis and simulation have revealed the growth rate, diffusion coefficient, and spatial distribution of the precursor. More importantly, a new vertex-kink-ledge model has been suggested for monolayer crystal growth. This work provides a new technique for in situ microscopic imaging at high temperatures and fundamental insight into 2D crystal growth.

2.
Oncologist ; 29(2): e248-e258, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-37874923

RESUMO

OBJECTIVE: To evaluate the presence and subtypes of tertiary lymphatic structures (TLSs) in urothelial carcinoma of the bladder (UCB) and to analyze their associated clinicopathological characteristics and prognostic significance. METHODS: The study enrolled 580 patients with surgically treated UCB, including 313 non-muscle invasive bladder cancer (NMIBC) and 267 muscle-invasive bladder cancer (MIBC). The presence and subtypes of TLSs were identified by immunohistochemistry (CD20, CD3, Bcl-6, and CD21). TLSs were classified into non-GC (nGC) TLS and GC TLS subtypes based on germinal center (GC) formation. Disease-free survival (DFS) was used as an endpoint outcome to evaluate the prognostic significance of TLS and its subtypes in UCB. RESULTS: TLSs were more common in MIBC than in NMIBC (67.8% vs 48.2%, P < .001), and the tumor-infiltrating lymphocyte (TIL) mean density was significantly higher in MIBC than in NMIBC (24.0% vs 17.5%, P < .001). Moreover, a positive correlation was found between TLS presence and GC structure formation and TIL infiltration in UCB. Endpoint events occurred in 191 patients. Compared to patients with endpoint events, patients without disease progression exhibited higher TIL density and more TLSs (P < .05). Kaplan-Meier curves showed that TLS was associated with better DFS in NMIBC (P = .041) and MIBC (P = .049). However, the Cox multivariate analysis did not demonstrate the prognostic significance of TLS. CONCLUSIONS: TLS is heterogeneous in UCB, and that TLS and GC structures are related to TIL density and prognostic events. However, TLS as a prognostic indicator remains unclear, warranting further investigation.


Assuntos
Carcinoma de Células de Transição , Neoplasias não Músculo Invasivas da Bexiga , Estruturas Linfoides Terciárias , Neoplasias da Bexiga Urinária , Humanos , Prognóstico , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Carcinoma de Células de Transição/cirurgia , Carcinoma de Células de Transição/patologia , Bexiga Urinária/cirurgia , Bexiga Urinária/patologia , Estruturas Linfoides Terciárias/patologia , Linfócitos do Interstício Tumoral/patologia
3.
Anal Chem ; 95(11): 4966-4973, 2023 03 21.
Artigo em Inglês | MEDLINE | ID: mdl-36890667

RESUMO

Fungicide abuse leads to the emergence of fungicide-resistant fungal pathogens, thus posing a threat to agriculture and food safety. Here, we developed an isothermal amplification refractory mutation system (termed iARMS) allowing us to resolve genetic mutations, enabling rapid, sensitive, and potentially field-applicable detection of fungicide-resistant crop fungal pathogens. iARMS yielded a limit of detection of 25 aM via a cascade signal amplification strategy of recombinase polymerase amplification (RPA) and Cas12a-mediated collateral cleavage at 37 °C within 40 min. Specificity for fungicide-resistant Puccinia striiformis (P. striiformis) detection was guaranteed by RPA primers and the flexible sequence of gRNA. The iARMS assay allowed us to detect as low as 0.1% cyp51-mutated P. striiformis that showed resistance to the demethylase inhibitor (DMI), which was 50 times more sensitive than the sequencing techniques. Thus, it is promising for the discovery of rare fungicide-resistant isolates. We applied iARMS to investigate the emergence of fungicide-resistant P. striiformis in western China and found that its proportion was over 50% in Qinghai, Sichuan, and Xinjiang Province. iARMS can serve as a molecular diagnostic tool for crop diseases and facilitate precision plant disease management.


Assuntos
Fungicidas Industriais , Fungicidas Industriais/farmacologia , Mutação , Fungos , Inocuidade dos Alimentos , China , Técnicas de Amplificação de Ácido Nucleico/métodos , Sensibilidade e Especificidade , Recombinases
4.
Soft Matter ; 19(4): 588-608, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36633123

RESUMO

Water-repellent interfaces with high performance have emerged as an indispensable platform for developing advanced materials and devices. Inspired by the pitcher plant, slippery liquid-infused porous surfaces (SLIPSs) with reliable hydrophobicity have proven to possess great potential for various applications in droplet and bubble manipulation, droplet energy harvesting, condensation, fog collection, anti-icing, and anti-biofouling due to their excellent properties such as persistent surface hydrophobicity, molecular smoothness, and fluidity. This review aims to introduce the development history of interaction between SLIPSs and fluids as well as the design principles, preparation methods, and various applications of some of the more typical SLIPSs. The fluid manipulation strategies of the slippery surfaces have been proposed including the wettability pattern, oriented micro-structure, and geometric gradient. At last, the application prospects of SLIPSs in various fields and the challenges in the design and fabrication of slippery surfaces are analyzed. We envision that this review can provide an overview of the fluid manipulating processes on slippery surfaces for researchers in both academic and industrial fields.

5.
J Biochem Mol Toxicol ; 37(8): e23387, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37247193

RESUMO

As the most common selenium derivative, methylseleninic acid (MSA) has attracted wide attention. Its apoptotic induction ability and the possible molecular mechanism in human bladder cancer (BC) J82 and T24 cells were investigated in the present study. We found that the survival of J82 and T24 cells were inhibited in a dose-dependent manner after MSA treatment. Propidium iodide (PI) staining and Annexin V-fluorescein isothiocyanate/PI double staining clarified that MSA stocked cells at G2 /M phase and caused apoptosis in J82 and T24 cells. Further, typical morphological features of apoptotic cells were also observed. Accumulation of reactive oxygen species (ROS) and loss of mitochondrial membrane potential were also detected by dichlorodihydrofluorescein diacetate and Rhodamin123 staining. Meanwhile, pretreatment with N-acetylcysteine, an ROS scavenging agent, found that the apoptosis of BC cells induced by MSA was related to the production of ROS. Western blot analysis results showed that MSA interrupted Bax/Bcl-2 balance, stimulated cytochrome c release into the cytoplasm, activated caspase-9 and caspase-3, and finally induced the apoptosis of the BC cells. These findings demonstrated that MSA was able to induce apoptosis in J82 and T24 cells through ROS-mediated mitochondrial apoptosis.


Assuntos
Apoptose , Neoplasias da Bexiga Urinária , Humanos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/metabolismo , Potencial da Membrana Mitocondrial
6.
J Environ Manage ; 348: 119494, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-37924696

RESUMO

Livestock is an important source of greenhouse gas emissions (GHGE) in China. Understanding the greenhouse gas (GHG) emission trends and reduction strategies in livestock is crucial for promoting low-carbon transformation of the livestock sector (LS) and achieving the goal of "carbon peak and carbon neutralization". First, based on the life cycle assessment and IPCC coefficient methods, we calculated the GHGE of the LS in 31 provinces of China from 2000 to 2020 and identified the temporal and spatial evolution of GHG emission intensity. The LMDI method was then used to analyze the influence of efficiency, structure, economy, and population size on GHGE. Finally, the STIRPAT model was used to simulate the future evolution trend of the LS emissions under the SSPs scenario. The results revealed that the GHGE in the life cycle of livestock production decreased from 535.47 Mt carbon dioxide equivalent (CO2e) in 2000 to 532.18 Mt CO2e in 2020, and the main source was CH4 emissions from enteric fermentation of livestock. Economic and efficiency factors markedly influenced the changes in GHGE from the LS in China. Further, economic factors contributed >40% to the increase in GHGE in most provinces. Under the SSP1, SSP2, and SSP4 scenarios, livestock production can achieve the carbon peak target in 2030. Under the baseline scenario (SSP2), the GHGE of China's LS in 2030 and 2060 are expected to be 491.48 Mt CO2e and 352.11 Mt CO2e, respectively. The focus of mitigation measures for livestock production in the future is to optimize the production structure of the LS, promote the low-carbon transformation of the energy structure of livestock feeding, and establish an efficient and intensive management model. In addition, we focus on emission reduction in key areas, such as Northeast and Northwest China, while optimizing diet and reducing food waste from the consumer side.


Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos , Animais , Efeito Estufa , Gado , Alimentos , China
7.
Molecules ; 28(23)2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38067533

RESUMO

The flower of Syringa pubescens Turcz. is used in Chinese folk medicine and also as a flower tea for healthcare. The effects of five drying methods on the active compound contents, the antioxidant abilities, anti-inflammatory properties and enzyme inhibitory activities were evaluated. The plant materials were treated using shade-drying, microwave-drying, sun-drying, infrared-drying and oven-drying. The seven active compounds were simultaneously determined using an HPLC method. Furthermore, the chemical profile was assessed using scanning electron microscopy, ultraviolet spectroscopy and infrared spectroscopy. The antioxidant capacities and protective effects on L02 cells induced with hydrogen peroxide were measured. The anti-inflammatory effects on lipopolysaccharide-induced RAW264.7 cells were investigated. The enzyme inhibitory activities were determined against α-amylase, α-glucosidase cholinesterases and tyrosinase. The results indicated that drying methods had significant influences on the active compound contents and biological properties. Compared with other samples, the OD samples possessed low IC50 values with 0.118 ± 0.004 mg/mL for DPPH radical, 1.538 ± 0.0972 for hydroxyl radical and 0.886 ± 0.199 mg/mL for superoxide radical, while the SHD samples had stronger reducing power compared with other samples. The SHD samples could be effective against H2O2-induced injury on L02 cells by the promoting of T-AOC, GSH-PX, SOD and CAT activities and the reducing of MDA content compared with other samples. Furthermore, SPF samples, especially the SHD sample, could evidently ameliorate inflammation through the inhibition of IL-6, IL-1ß and TNF-α expression. All the studied SPF samples exhibited evidently inhibitory effects on the four enzymes. The IC50 values of inhibitory activity on α-glucosidase and α-amylase from SHD sample were 2.516 ± 0.024 and 0.734 ± 0.034 mg/mL, respectively. SD samples had potential inhibitory effects on cholinesterases and tyrosinase with IC50 values of 3.443 ± 0.060 and 1.732 ± 0.058 mg/mL. In consideration of active compound contents and biological activities, it was recommended that SHD and SD be applied for drying SPF at an industrial scale.


Assuntos
Antioxidantes , Syringa , Antioxidantes/farmacologia , Antioxidantes/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Monofenol Mono-Oxigenase , alfa-Glucosidases , Peróxido de Hidrogênio , Anti-Inflamatórios/farmacologia , Flores , alfa-Amilases , Colinesterases
8.
Proc Natl Acad Sci U S A ; 116(22): 10937-10942, 2019 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-31085638

RESUMO

Mirabegron (Myrbetriq) is a ß3-adrenoreceptor agonist approved for treating overactive bladder syndrome in human patients. This drug can activate brown adipose tissue (BAT) in adult humans and rodents through the ß3-adrenoreceptor-mediated sympathetic activation. However, the effect of the mirabegron, approved by the US Food and Drug Administration, on atherosclerosis-related cardiovascular disease is unknown. Here, we show that the clinical dose of mirabegron-induced BAT activation and browning of white adipose tissue (WAT) exacerbate atherosclerotic plaque development. In apolipoprotein E-/- (ApoE-/-) and low-density lipoprotein (LDL) receptor-/- (Ldlr-/-) mice, oral administration of clinically relevant doses of mirabegron markedly accelerates atherosclerotic plaque growth and instability by a mechanism of increasing plasma levels of both LDL-cholesterol and very LDL-cholesterol remnants. Stimulation of atherosclerotic plaque development by mirabegron is dependent on thermogenesis-triggered lipolysis. Genetic deletion of the critical thermogenesis-dependent protein, uncoupling protein 1, completely abrogates the mirabegron-induced atherosclerosis. Together, our findings suggest that mirabegron may trigger cardiovascular and cerebrovascular diseases in patients who suffer from atherosclerosis.


Assuntos
Acetanilidas/farmacologia , Tecido Adiposo Marrom/efeitos dos fármacos , Aterosclerose/patologia , Lipólise/efeitos dos fármacos , Tiazóis/farmacologia , Agentes Urológicos/farmacologia , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/efeitos dos fármacos , Tecido Adiposo Branco/metabolismo , Animais , Aterosclerose/fisiopatologia , LDL-Colesterol/sangue , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout para ApoE , Receptores de LDL/genética
9.
J Craniofac Surg ; 33(2): e118-e122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34334752

RESUMO

OBJECTIVE: The aim of this study was to investigate the effectiveness, safety, complications, and prognosis of endoscopic endonasal surgery for pituitary adenomas with cavernous sinus invasion (CSI). METHODS: The clinical data of 803 pituitary adenomas with CSI surgeries performed in our single ward between January 1, 2006 and December 31, 2018 were retrospectively reviewed. The resection degree, bone invasion, endocrine examination, complications, and outcome were retrospectively summarized. RESULTS: Gross total resection was achieved in 394 patients (49.1%) subtotal resection in 171 patients (21.3%) and partial resection in 238 patients (29.6%). Clinically variable analyses showed that there was a significant correlation between CSI and female, older age, operation history, and non-gross total resection (NGTR). Among the pituitary adenomas with CSI, there was a significant correlation between bone invasive and NGTR, Knosp classification, recurrence. K-M curves showed that young age, larger tumors, bilateral invasion, Grade 4 of Knosp classification, NGTR, and bone invasion were associated with pituitary adenomas regrowth. Multivariate analysis revealed that bone invasion, NGTR, and Grade 4 of Knosp classification were independent risk factors for pituitary adenomas regrowth. There was a significant correlation between CSI and female, older age, operation history, and tumor resection degree. CONCLUSIONS: There was a significant correlation between CSI and female, older age, operation history, and tumor resection degree. The patients with CSI and bone invasion were likely to recurrent. Non-gross total resection, bone invasion, and Grade 4 of Knosp classification were independent risk factors for pituitary adenomas regrowth. Endoscopic endonasal surgery is an excellent choice for pituitary adenomas with CSI.


Assuntos
Adenoma , Seio Cavernoso , Neoplasias Hipofisárias , Adenoma/cirurgia , Seio Cavernoso/patologia , Seio Cavernoso/cirurgia , Feminino , Humanos , Processos Neoplásicos , Nariz/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem , Neoplasias Hipofisárias/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
10.
Int J Mol Sci ; 23(23)2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36499285

RESUMO

The utilization of symbiosis with beneficial microorganisms has considerable potential for increasing growth and resistance under abiotic stress. The endophytic root fungus Piriformospora indica has been shown to improve plant growth under salt and drought stress in diverse plant species, while there have been few reports of the interaction of P. indica with soybean under salt stress. In this study, the symbiotic system of P. indica and soybean (Glycine max L.) was established, and the effect of P. indica on soybean growth and salt tolerance was investigated. The colonized and non-colonized soybeans were subjected to salt stress (200 mmol/L NaCl), and the impairments in chlorophyll and increasing relative conductivity that can be caused by salt stress were alleviated in the P. indica-colonized plants. The accumulation of malondialdehyde (MDA), hydrogen peroxide (H2O2), and superoxide anion (O2−) were lower than that in non-colonized plants under salt treatment, whereas the activities of antioxidant enzymes were significantly increased by P. indica colonization, including superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), and glutathione reductase (GR). Importantly, without salt treatment, the Na+ concentration was lower, and the K+ concentration was higher in the roots compared with non-colonized plants. Differential expressions of ion transporter genes were found in soybean roots after P. indica colonization. The P. indica colonization positively regulated the transcription level of PM H+-ATPase, SOS1, and SOS2. The study shows that P. indica enhances the growth and salt tolerance of soybean, providing a strategy for the agricultural production of soybean plants in saline-alkali soils.


Assuntos
Basidiomycota , Glycine max , Antioxidantes/farmacologia , Peróxido de Hidrogênio/metabolismo , Basidiomycota/genética , Tolerância ao Sal/genética , Expressão Gênica , Raízes de Plantas
11.
Int J Mol Sci ; 23(17)2022 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-36077224

RESUMO

Rare cold-inducible 2 (RCI2) genes from alfalfa (Medicago sativa L.) are part of a multigene family whose members respond to a variety of abiotic stresses by regulating ion homeostasis and stabilizing membranes. In this study, salt, alkali, and ABA treatments were used to induce MsRCI2D and MsRCI2E expression in alfalfa, but the response time and the expression intensity of the MsRCI2D,-E genes were different under specific treatments. The expression intensity of the MsRCI2D gene was the highest in salt- and alkali-stressed leaves, while the MsRCI2E gene more rapidly responded to salt and ABA treatment. In addition to differences in gene expression, MsRCI2D and MsRCI2E differ in their subcellular localization. Akin to MtRCI2D from Medicago truncatula, MsRCI2D is also localized in the cell membrane, while MsRCI2E is different from MtRCI2E, localized in the cell membrane and the inner membrane. This difference might be related to an extra 20 amino acids in the C-terminal tail of MsRCI2E. We investigated the function of MsRCI2D and MsRCI2E proteins in alfalfa by generating transgenic alfalfa chimeras. Compared with the MsRCI2E-overexpressing chimera, under high-salinity stress (200 mmol·L-1 NaCl), the MsRCI2D-overexpressing chimera exhibited a better phenotype, manifested as a higher chlorophyll content and a lower MDA content. After salt treatment, the enzyme activities of SOD, POD, CAT, and GR in MsRCI2D- and -E-overexpressing roots were significantly higher than those in the control. In addition, after salt stress, the Na+ content in MsRCI2D- and -E-transformed roots was lower than that in the control; K+ was higher than that in the control; and the Na+/K+ ratio was lower than that in the control. Correspondingly, H+-ATPase, SOS1, and NHX1 genes were significantly up-regulated, and the HKT gene was significantly down-regulated after 6 h of salt treatment. MsRCI2D was also found to regulate the expression of the MsRCI2B and MsRCI2E genes, and the MsRCI2E gene could alter the expression of the MsRCI2A, MsRCI2B, and MsRCI2D genes. MsRCI2D- and -E-overexpressing alfalfa was found to have higher salt tolerance, manifested as improved activity of antioxidant enzymes, reduced content of reactive oxygen species, and sustained Na+ and K+ ion balance by regulating the expression of the H+-ATPase, SOS1, NHX1, HKT, and MsRCI2 genes.


Assuntos
Medicago sativa , Tolerância ao Sal , Álcalis/metabolismo , Antioxidantes/metabolismo , Regulação da Expressão Gênica de Plantas , Homeostase , Medicago sativa/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Tolerância ao Sal/genética , Sódio/metabolismo
12.
Pak J Pharm Sci ; 35(1): 35-40, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35221270

RESUMO

Syringa pubescens Turcz is commonly used folk medicinal herb in west of Henan Province of China. In this work, water and various concentration of methanol, ethanol and acetone in water were used as solvent to extract echinacoside and oleuropein from S. pubescens. The antioxidant properties of different extracts were evaluated using various in vitro assays. The highest yields of echinacoside and oleuropein were obtained by using the 60% aqueous methanol and 80% aqueous ethanol, respectively. The extracts of water, aqueous ethanol or methanol showed strong antioxidant abilities. Furthermore, the high correlation between echinacoside content and antioxidant properties was found. The contribution of oleuropein content was not significant to antioxidant abilities. These findings indicate that S. pubescens can be used as a new natural antioxidant resource.


Assuntos
Antioxidantes/farmacologia , Glicosídeos/farmacologia , Glucosídeos Iridoides/farmacologia , Fitoterapia , Syringa/química , Acetona , Antioxidantes/química , Medicamentos de Ervas Chinesas , Etanol , Glicosídeos/química , Glucosídeos Iridoides/química , Metanol , Solventes/química , Água
13.
Small ; 17(8): e2007803, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33522147

RESUMO

Lubricant-infused slippery surface exhibits a series of superior properties such as pressure tolerance, self-healing, oil-repellence, etc. Especially when being applied in an aqueous environment, the reliable bubble manipulating ability of slippery surface offers great opportunities to develop advanced systems in the field of gas transport, water splitting, etc. To improve the strength and the functionality of slippery surfaces, a sliced lubricant-infused slippery (SLIS) track is presented here, possessing both flexibility and toughness for underwater bubble manipulation. The rigid slippery slices with hydrophobic porous structure are linked by the liquid bridge of silicone oil, resulting in a continuous lubricant layer for bubble transfer. Taking advantage of this unique assembled structure, the in situ bubble controlling process, that is, pinning and moving, is achieved via the stretching/releasing of an elastic SLIS track. Besides, on the basis of the integrated design, a hypothesis of underwater gas mining is proved in the all-in-one process including the micro-bubble generation, bubble collection, and gas transport. The current design paves an avenue to reinforce the structure of slippery surfaces, and should promote the function of underwater bubble manipulation toward real-world applications.


Assuntos
Lubrificantes , Água , Interações Hidrofóbicas e Hidrofílicas , Porosidade
14.
Phytochem Anal ; 32(6): 1074-1081, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33837595

RESUMO

INTRODUCTION: Syringa pubescens Turcz. was reported to be abundant in the Funiu Mountains of Henan Province and can be used to treat hepatitis and cirrhosis. In order to develop and utilise the resource, a fast and simple technique to extract bioactive compounds is needed. OBJECTIVES: Our aims were to provide an extraction technique of glycosides from S. pubescens and study the antioxidant activity of this material. METHODS: Box-Behnken design (BBD) was employed with three factors at three levels. The process parameters such as ethanol concentration (X1 ), temperature (X2 ), and solvent-solid ratio (X3 ) could significantly influence efficiency and yield of target compounds. High-performance liquid chromatography (HPLC) was used to determine the content of glycosides. DPPH (α,α-diphenyl-ß-picrylhydrazyl), ABTS (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) and reducing power were used to evaluate the antioxidant activity of S. pubescens extract. RESULTS: The optimal parameters for the maximal extraction yield were obtained with ethanol concentration of 68%, temperature of 89°C, solvent-solid ratio of 46 mL/g, and time of 20 min. The S. pubescens extract showed strong antioxidant properties in vitro. CONCLUSION: The findings indicated the potential application of solvothermal extraction method to extract bioactive compounds from S. pubescens Turcz. Furthermore, the S. pubescens extract could be used as an important resource of antioxidant activity.


Assuntos
Syringa , Antioxidantes , Glicosídeos , Glucosídeos Iridoides
15.
J Cell Biochem ; 121(1): 81-92, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31081133

RESUMO

Prostate cancer (PC) is one of the most common malignant tumors in man. Peimine (PM) is a bioactive substance isolated from Fritillaria. Previous studies have shown that PM could inhibit the occurrence of a variety of cancers. However, the roles of PM in PC and its related mechanism have not been elucidated. Calcium (Ca2+ ) is an important intracellular messenger involved in a variety of cell processes. In this study, we found that the appropriate doses of PM (2.5, 5, and 10 µM) significantly inhibited the growth of PC cells (DU-145, LNCap, and PC-3), but has no significant effect on normal prostate cells (RWPE-1). In addition, PM treatment inhibited the invasion and migration of PC-3 cells and blocked the epithelial-mesenchymal transition process. These effects were exhibited a dose-dependent manner. Furthermore, the current results also showed that PM treatment significantly increased the Ca2+ concentration, the increased Ca2+ promoted the phosphorylation of Ca2+ /calmodulin-dependent protein kinase II (CaMKII) and c-Jun N-terminal kinase (JNK), further inhibited the growth and invasion of PC-3 cells, and induced its apoptosis. Ca2+ chelator BAPTA-AM (1 µM) could counteract the increase of intracellular Ca2+ concentration. Similarly, JNK pathway inhibitor SP600125 (10 µM) also inhibited cell growth and invasion and induced apoptosis. In addition, experiments in nude mice showed that PM inhibited tumor formation through Ca2+ /CaMKII/JNK signaling pathway. In conclusion, our results show that PM inhibits the growth and motility of prostate cancer cells and induces apoptosis by disruption of intracellular calcium homeostasis through Ca2+ /CaMKII/JNK pathway.


Assuntos
Apoptose , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Cálcio/metabolismo , Cevanas/farmacologia , MAP Quinase Quinase 4/metabolismo , Neoplasias da Próstata/metabolismo , Animais , Antracenos/farmacologia , Sinalização do Cálcio , Linhagem Celular Tumoral , Movimento Celular , Sobrevivência Celular , Fritillaria/química , Homeostase/efeitos dos fármacos , Humanos , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Transplante de Neoplasias , Fosforilação , Cicatrização
16.
Neurosurg Rev ; 43(5): 1373-1381, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31493062

RESUMO

To investigate the effectiveness of endoscopic fenestration in the patients with prior failed ventriculoperitoneal (VP) shunt treatment of suprasellar arachnoid cysts (SACs). Between 2012 and 2018, four pediatric patients of SACs with previous failed VP shunt treatment were surgically treated using endoscopic ventriculocystocisternostomy (VCC) in our hospital. The clinical symptoms, imaging data, and surgical outcomes were collected and analyzed retrospectively. A literature review is provided with regard to the reasons of shunt failure and surgical outcome of further endoscopic fenestration in the previously reported patients of SACs with prior failed VP shunt. For the 4 cases, the initial clinical symptoms relieved or even disappeared after shunt placement, but, respectively, recurred 2, 6, 11, and 6 months later. MR scans were conducted when the clinical symptoms reappeared and showed a cyst had greatly enlarged after shunt placement. Furthermore, VP shunt-related slit ventricle was also demonstrated in 3 cases. Clinical improvement and cysts shrinkage occurred in all 4 patients after VCC. Slit ventricle and hydrocephalus were also resolved. Three patients had their shunt apparatus removed after VCC, and another patient's guardian refused to remove the shunt apparatus. Subdural hematoma occurred in one case after shunt apparatus removal. Four patients have been stable during follow-up period (mean follow-up 26.5 months). All the three patients whose VP shunt were removed were shunt independence. There were 24 patients who underwent endoscopic fenestration as an alternative to the failed VP shunt treatment in the published reports. Added our 4 patients to the published group, the effective rate of endoscopic fenestration for SACs following previous failed VP shunt treatment was approximately 93% (26/28). Of the 24 patients, the shunt apparatuses were in situ or reimplantation in 9 patients due to shunt dependence. The correction to recognize the SAC is the first condition to select the optimal management philosophy. The analysis of the series suggests endoscopic operation is still an effective and safe option in the SAC patients with previous failed VP shunt, and the shunt apparatus can be removed for some patients. The short interval time between shunt operation and endoscopic fenestration is conductive to return patients to the shunt-free state.


Assuntos
Cistos Aracnóideos/cirurgia , Cistos do Sistema Nervoso Central/cirurgia , Endoscopia/métodos , Procedimentos Neurocirúrgicos/métodos , Derivação Ventriculoperitoneal/efeitos adversos , Cistos Aracnóideos/diagnóstico por imagem , Cistos do Sistema Nervoso Central/diagnóstico por imagem , Pré-Escolar , Feminino , Seguimentos , Hematoma Subdural/etiologia , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Complicações Pós-Operatórias/epidemiologia , Falha de Tratamento , Resultado do Tratamento
17.
Proc Natl Acad Sci U S A ; 114(26): E5226-E5235, 2017 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-28607065

RESUMO

Long-term uninterrupted therapy is essential for maximizing clinical benefits of antiangiogenic drugs (AADs) in cancer patients. Unfortunately, nearly all clinically available AADs are delivered to cancer patients using disrupted regimens. We aim to develop lifetime, nontoxic, effective, orally active, and low-cost antiangiogenic and antitumor drugs for treatment of cancer patients. Here we report our findings of long-term maintenance therapy with orally active, nontoxic, low cost antiangiogenic chemotherapeutics for effective cancer treatment. In a sequential treatment regimen, robust antiangiogenic effects in tumors were achieved with an anti-VEGF drug, followed by a low-dose chemotherapy. The nontoxic, low dose of the orally active prodrug capecitabine was able to sustain the anti-VEGF-induced vessel regression for long periods. In another experimental setting, maintenance of low-dose capecitabine produced greater antiangiogenic and antitumor effects after AAD plus chemotherapy. No obvious adverse effects were developed after more than 2-mo of consecutive treatment with a low dose of capecitabine. Together, our findings provide a rationalized concept of effective cancer therapy by long-term maintenance of AAD-triggered antiangiogenic effects with orally active, nontoxic, low-cost, clinically available chemotherapeutics.


Assuntos
Capecitabina/farmacologia , Neoplasias Experimentais , Neovascularização Patológica , Células A549 , Administração Oral , Animais , Ensaios de Seleção de Medicamentos Antitumorais , Feminino , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Neoplasias Experimentais/irrigação sanguínea , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Neovascularização Patológica/tratamento farmacológico , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Fatores de Tempo
18.
Proc Natl Acad Sci U S A ; 114(45): E9635-E9644, 2017 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-29078273

RESUMO

Anti-VEGF drugs are commonly used for treatment of a variety of cancers in human patients, and they often develop resistance. The mechanisms underlying anti-VEGF resistance in human cancer patients are largely unknown. Here, we show that in mouse tumor models and in human cancer patients, the anti-VEGF drug-induced kidney hypoxia augments circulating levels of erythropoietin (EPO). Gain-of-function studies show that EPO protects tumor vessels from anti-VEGF treatment and compromises its antitumor effects. Loss of function by blocking EPO function using a pharmacological approach markedly increases antitumor activity of anti-VEGF drugs through inhibition of tumor angiogenesis. Similarly, genetic loss-of-function data shows that deletion of EpoR in nonerythroid cells significantly increases antiangiogenic and antitumor effects of anti-VEGF therapy. Finally, in a relatively large cohort study, we show that treatment of human colorectal cancer patients with bevacizumab augments circulating EPO levels. These findings uncover a mechanism of desensitizing antiangiogenic and anticancer effects by kidney-produced EPO. Our work presents conceptual advances of our understanding of mechanisms underlying antiangiogenic drug resistance.


Assuntos
Inibidores da Angiogênese/farmacologia , Antineoplásicos/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Eritropoetina/metabolismo , Rim/efeitos dos fármacos , Neovascularização Patológica/tratamento farmacológico , Animais , Bevacizumab/farmacologia , Estudos de Coortes , Neoplasias Colorretais/metabolismo , Humanos , Rim/metabolismo , Camundongos , Neovascularização Patológica/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo
19.
Minim Invasive Ther Allied Technol ; 29(6): 317-325, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31495241

RESUMO

Background: Microscopic transsphenoidal surgery (MTS) has been considered as the gold standard for transsphenoidal pituitary surgery, but nowadays endoscopic transsphenoidal surgery (ETS) has become popular due to its wide view and improved lighting.Material and methods: The electronic databases were systematically searched, and the meta-analyses of the eligible studies that evaluated endoscopic versus microscopic methods in patients with pituitary surgery were conducted with Review Manager 5.0. The primary outcomes included visual improvement, gross tumor removal (GTR), cerebrospinal fluid (CFS) leak, diabetes insipidus (DI), other complications, and length of hospital stay. The Egger's test was conducted to estimate possible publication bias.Results: In total, 13 articles eventually met the inclusion criteria. The meta-analyses suggested that the differences with regard to visual improvement, overall complication rate, GTR, CSF leak, diabetes insipidus (DI), meningitis, visual impairment, syndrome of inappropriate antidiuretic hormone secretion (SIADH), new onset hypopituitarism, and hypothyroidism between the endoscopic and microscopic groups were not statistically significant. The length of hospital stay was much longer with the microscopic approach when compared with the endoscopic method.Conclusion: The endoscopic and microscopic approaches show similar effects and complication rates. The endoscopic technique could be adopted as a reasonable alternative in pituitary surgery.


Assuntos
Endoscopia , Iluminação , Hipófise , Humanos , Tempo de Internação , Hipófise/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Osso Esfenoide/cirurgia , Resultado do Tratamento
20.
Nanotechnology ; 30(3): 034003, 2019 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-30444726

RESUMO

With its atomically smooth surface yet no dangling bond, chemical inertness and high temperature sustainability, the insulating hexagonal boron nitride (h-BN) can be an ideal substrate for two-dimensional (2D) material growth and device measurement. In this review, research progress on the chemical growth of 2D materials on h-BN has been summarized, such as chemical vapor deposition and molecular beam epitaxy of graphene and various transition metal dichalcogenides. Further, stacking of the as-grown 2D materials relative to h-BN, thermal expansion matching between the deposited materials and h-BN, electrical property of 2D materials on h-BN have been discussed in detail.

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