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1.
J Hazard Mater ; 421: 126735, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34343882

RESUMO

Renewable wood sponge with lamellar structure, compressibility and three-dimensional porous frameworks exhibits excellent functionalization application potential in various fields. Herein, cobalt and nitrogen (Co/N) co-doped carbonized wood sponge (CoNCWS800) was prepared successfully for peroxymonosulfate (PMS) activation to degrade sulfamethoxazole (SMX). The CoNCWS800 material exhibited admirable catalytic activity in PMS activation to oxidize SMX molecules (99.7% within 60 min). Electron paramagnetic resonance (EPR) analysis, quenching tests and electrochemical experiments confirmed the existence of both radical (SO4·-,·OH and O2·-) and non-radical (1O2 and direct charge transfer) pathways during the SMX degradation process. Co species were verified as major contributors for the generation of multiple radicals via activating PMS. Surface defective structure and ketonic CO groups performed the positive linear correlation with reaction kinetic constants, revealing the critical role of the two active sites in PMS activation via non-radical process. This study provides a unique insight in PMS activation mechanism via both radical and non-radical pathways of wood sponge-based functional materials.


Assuntos
Cobalto , Nitrogênio , Peróxidos , Porosidade , Madeira
2.
J Hazard Mater ; 421: 126794, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34365236

RESUMO

Conversion of digestate into biochar-based catalysts is an effective strategy for disposal and resource utilization. The active sites on biochar correlated with reactive species formation in peroxymonosulfate (PMS) system directly. Clarifying the structure-performance relationship of digestate derived biochar in PMS system was essential for decomposition of contaminants. Herein, dairy manure digestate derived biochar (DMDB) was prepared for PMS activation and sulfamethoxazole (SMX) degradation. The higher pyrolysis temperature could promote effective sites generation. Especially, the DMDB-800 catalyst exhibited excellent performance for PMS activation, achieving 90.2% degradation of SMX within 60 min. Based on the correlation analysis between log (k) values and active sites, defects, graphite N and CO were identified as dominant sites for PMS activation. The 1O2 oxidation and surface electron transfer were critical routes for SMX degradation. Besides, the degradation pathways of SMX were proposed according to DFT calculations and intermediates determination. The cleavage of the sulfonamide bond, hydroxylation of the benzene ring and oxidation of the amino group mainly occurred during SMX degradation. Overall, this study provides deep insights into the enhanced mechanism of tunable active sites on DMDBs for PMS activation, boosting the application of digestate biochar for water treatment in advanced oxidation systems.


Assuntos
Biocombustíveis , Peróxidos , Domínio Catalítico , Carvão Vegetal , Sulfanilamida
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 264: 120275, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34411769

RESUMO

A turn on upconversion fluorescence probe based on the combination of ~32 nm NaYF4: Yb/Tm nanoparticles and MnO2 nanosheets has been established for rapid, sensitive detection of Fe2+ ions levels in aqueous solutions and serum. X-ray diffraction (XRD), transmission electron microscopy (TEM), absorption and emission spectra have been used to characterize the crystal structure, morphology and optical properties of the samples. MnO2 nanosheets on the surface of UCNPs act as a fluorescence quencher, resulting in the quenching of the blue fluorescence (with excitation/emission maximum of 980/476 nm) via fluorescence resonance energy transfer from upconversion nanoparticles to MnO2 nanosheets. With the adding of Fe2+, upconversion fluorescence of the nanocomposites recovers due to the reduction of MnO2 to Mn2+. Because of the low background of the probe offered by upconversion fluorescence, this probe can be used for detecting Fe2+ in aqueous solutions in the range of 0.1-22 µM with detection limit of 0.113 µM. The developed method has also been applied to detect 10 µM Fe2+ ions in serum with recoveries ranging from 97.6 to 105.3% for the five serum samples. Significantly, the probe shows fast response and stable signal, which is beneficial for long-time dynamic sensing. Thus, the proposed strategy holds great potential for disease diagnosis and treatment.


Assuntos
Compostos de Manganês , Nanopartículas , Transferência Ressonante de Energia de Fluorescência , Íons , Óxidos
4.
Food Chem ; 370: 131295, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34788955

RESUMO

Browning seriously causes postharvest deterioration of the yellow cultivars of Flammulina filiformis, yet the browning process and its mechanism have not been described. Changes of L*, a*, b* values, the browning and whiteness index during air contacted storage were evaluated, uncovering the great loss of brightness and meanwhile the accumulation of yellowness and redness. Browning tissue showed an increase of malondialdehyde, total phenolics, and browning-related enzyme activities of polyphenol oxidase and peroxidase, in contrast to the decrease of bioprotective catalase, superoxide, and dismutase. Non-targeted metabolomics revealed an upregulation of melanin synthesis under oxidation stress, and targeted LC-MS/MS verified the upregulation of l-dopa (3,4-dihydroxy-l-phenylalanine) during browning. Pyrrole-2,3,5-tricarboxylic acid was identified in the degradation products of browning pigments after alkaline hydrogen peroxide by LC-MS/MS, suggesting the existence of 5,6-dihydroxyindole-2-carboxylic acid derived units of eumelanin. Therefore, the biosynthesis of eumelanin via l-dopa pathway could participate in the enzymatic browning of postharvest F. filiformis.


Assuntos
Agaricales , Flammulina , Cromatografia Líquida , Di-Hidroxifenilalanina/análogos & derivados , Metabolômica , Espectrometria de Massas em Tandem
5.
Sci Total Environ ; 802: 149946, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34525759

RESUMO

Photovoltaic technology plays an important role in the sustainable development of clean energy, and arid areas are particularly ideal locations to build large-scale solar farms, all over the world. Modifications to the energy balance and water availability through the installation of large-scale solar farms, however, fundamentally affect the energy budget, water, and biogeochemical cycles. In-situ field observations, though, fail to draw definitive conclusions on how photovoltaic panels (PVs) affect the ambient environment, or how microclimates and soil moisture evolve under the long-term, continuous, cumulative influence of PVs. Here, we designed a synthetic model, integrating processes of energy budget and water cycle, to quantify the ecohydrological effects of PVs on soil microclimate and moisture regimes at different locations (zones) near individual PVs. Simulations run with a stochastically generated 100-year climate time series were examined to capture the evolutionary trends of soil microclimate and soil moisture. The results indicate that soil moisture content was increased by 59.8% to 113.6% in the Middle and Front zones, and soil temperature was decreased by 1.47 to 1.66 °C in all the sheltered zones, mainly because there was 5- 7 times more available water and ~27% less available radiation there, compared with the control zone. On the other hand, if the ground clearance of the PVs is too low, turbulence beneath hot PVs will have a significant influence on not only soil temperature but also soil moisture content. The innovative contribution of this study lies in reinforcing existing theoretical patterns for the development of soil microclimate and moisture dynamics influenced by PVs, and can be used to provide reliable insights into the hydrological and biogeochemical processes on Earth and the sustainable management of large-scale solar farms in arid ecosystems.


Assuntos
Microclima , Solo , China , Ecossistema , Fazendas , Água/análise
6.
Front Immunol ; 12: 759323, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34721434

RESUMO

Lauric acid (LA) is a crucial medium-chain fatty acid (MCFA) that has many beneficial effects on humans and animals. This study aimed to investigate the effects of LA on the intestinal barrier, immune functions, serum metabolism, and gut microbiota of broilers under lipopolysaccharide (LPS) challenge. A total of 384 one-day-old broilers were randomly divided into four groups, and fed with a basal diet, or a basal diet supplemented with 75 mg/kg antibiotic (ANT), or a basal diet supplemented with 1000 mg/kg LA. After 42 days of feeding, three groups were intraperitoneally injected with 0.5 mg/kg Escherichia coli- derived LPS (LPS, ANT+LPS and LA+LPS groups) for three consecutive days, and the control (CON) group was injected with the same volume of saline. Then, the birds were sacrificed. Results showed that LA pretreatment significantly alleviated the weight loss and intestinal mucosal injuries caused by LPS challenge. LA enhanced immune functions and inhibited inflammatory responses by upregulating the concentrations of immunoglobulins (IgA, IgM, and IgY), decreasing IL-6 and increasing IL-4 and IL-10. Metabolomics analysis revealed a significant difference of serum metabolites by LA pretreatment. Twenty-seven serum metabolic biomarkers were identified and mostly belong to lipids. LA also markedly modulated the pathway for sphingolipid metabolism, suggesting its ability to regulate lipid metabolism. Moreover,16S rRNA analysis showed that LA inhibited LPS-induced gut dysbiosis by altering cecal microbial composition (reducing Escherichia-Shigella, Barnesiella and Alistipes, and increasing Lactobacillus and Bacteroides), and modulating the production of volatile fatty acids (VFAs). Pearson's correlation assays showed that alterations in serum metabolism and gut microbiota were strongly correlated to the immune factors; there were also strong correlations between serum metabolites and microbiota composition. The results highlight the potential of LA as a dietary supplement to combat bacterial LPS challenge in animal production and to promote food safety.

7.
Front Oncol ; 11: 751086, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722305

RESUMO

In the past decade, cancer immunotherapy has achieved great success owing to the unravelling of unknown molecular forces in cancer immunity. However, it is critical that we address the limitations of current immunotherapy, including immune-related adverse events and drug resistance, and further enhance current immunotherapy. Lipids are reported to play important roles in modulating immune responses in cancer. Cancer cells use lipids to support their aggressive behaviour and allow immune evasion. Metabolic reprogramming of cancer cells destroys the equilibrium between lipid anabolism and catabolism, resulting in lipid accumulation within the tumour microenvironment (TME). Consequently, ubiquitous lipids, mainly fatty acids, within the TME can impact the function and phenotype of infiltrating immune cells. Determining the complex roles of lipids and their interactions with the TME will provide new insight for improving anti-tumour immune responses by targeting lipids. Herein, we present a review of recent literature that has demonstrated how lipid metabolism reprogramming occurs in cancer cells and influences cancer immunity. We also summarise the potential for lipid-based clinical translation to modify immune treatment.

8.
J Am Chem Soc ; 143(46): 19517-19524, 2021 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-34762414

RESUMO

We report the synthesis and characterization of two water-soluble container compounds (cavitand hosts) with rigidified open ends. One cavitand uses four (CH2)4's as spacers to bridge the adjacent walls, while another cavitand uses four CH2CH2OCH2CH2's bridges and features a wider open end. The spacers preorganize the deep cavitands into vase-like, receptive shapes and prevent their unfolding to the unreceptive kite-like conformation. Cycloalkane guests (C6-C8) and small n-alkanes (C5-C7) form 1:1 complexes with the cavitands and move freely in the cavitands' spaces. Hydrophilic compounds 1,4-dioxane, tetrahydrofuran, tetrahydropyran, pyridine, and 1-methylimidazole also showed good binding affinity to the new cavitands. Longer alkanes (C11-C14) and n-alcohols (C11-C16) are taken up with a -CH3 group fixed at the bottom of the cavity and the groups near the rim in compressed conformations. The methylene bridges appear to divide the cavitand into a narrow hydrophobic compartment and a broader space with exposure to the aqueous medium. Longer alkane guests (C15-C18), N,N-dimethyldioctylammonium, and dioctylamine induce the formation of capsules (2:1 host:guest complexes). The new cavitands showed selectivity for p/m-cresol isomers and xylene isomers. The cavitand with CH2CH2OCH2CH2 bridges bound long-chain α,ω-diols (C13-C15) and diamines in folded, U-shaped conformations with polar functions exposed to the aqueous medium. It was used to separate o-xylene from its isomers by using simple extraction procedures.

9.
Biomaterials ; 279: 121242, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34768151

RESUMO

Osteolysis at the tendon-bone interface can impair pullout strength during tendon-bone healing and lead to surgery failure, but the effects of clinical treatments are not satisfactory. Mesenchymal stem cell (MSC)-derived exosomes have been used as potent and feasible natural nanocarriers for drug delivery and have been proven to enhance tendon-bone healing strength, indicating that MSC-derived exosomes could be a promising therapeutic strategy. In this study, we explored Scleraxis (Scx) dynamically expressed in PDGFRα(+) bone marrow-derived mesenchymal stem cells (BMMSCs) during natural tendon-bone healing. Then, we investigated the role of PDGFRα(+) BMMSCs in tendon-bone healing after Scx overexpression as well as the underlying mechanisms. Our data demonstrated that Scx-overexpressing PDGFRα(+) BMMSCs (BMMSCScx) could efficiently inhibit peritunnel osteolysis and enhance tendon-bone healing strength by preventing osteoclastogenesis in an exosomes-dependent manner. Exosomal RNA-seq revealed that the abundance of a novel miRNA, miR-6924-5p, was highest among miRNAs. miR-6924-5p could directly inhibit osteoclast formation by binding to the 3'-untranslated regions (3'UTRs) of OCSTAMP and CXCL12. Inhibition of miR-6924-5p expression reversed the prevention of osteoclastogenic differentiation by BMMSCScx derived exosomes (BMMSCScx-exos). Local injection of BMMSCScx-exos or miR-6924-5p dramatically reduced osteoclast formation and improved tendon-bone healing strength. Furthermore, delivery of miR-6924-5p efficiently inhibited the osteoclastogenesis of human monocytes. In brief, our study demonstrates that BMMSCScx-exos or miR-6924-5p could serve as a potential therapy for the treatment of osteolysis during tendon-bone healing and improve the outcome.

10.
Iran J Basic Med Sci ; 24(8): 1050-1057, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34804422

RESUMO

Objectives: Colitis has a high prevalence rate, limited treatment options, and needs to be solved urgently. Application of Licochacone A (LA) or rBMMSCs alone in the treatment of colitis has a certain but limited effect. This study aims to develop an LA-based strategy to improve mesenchymal stem cells' (MSCs') therapeutic capacity in mice DSS-induced colitis by increasing the number of MSCs migrating to the inflammation site. Materials and Methods: In vivo, we injected MSCs pretreated with LA, MSCs alone, or PBS into the tail vein of colitis mice, and assessed the colon length, disease activity index (DAI) score, body weight, HAI score, and tracked the location of MSCs at day 10. In vitro, we knocked down the CXCR4 gene by siRNA and then treated it with LA, then tested the mRNA level of CXCR4 and the migration ability of group CXCR4, CXCR4+LA, LA, and control to verify the relationship between this effect and the SDF-1-CXCR4 signaling pathway. Results: The mice that received LA- pretreated MSCs had ameliorated body weight loss, preserved colon morphology, and decreased DAI and histological activity index (HAI) compared with the MSCs group. Besides, the number of MSCs migrating to the inflammation site significantly increased in group LA+MSCs, and expression of CXCR4 significantly increased too. Furthermore, we found that LA could partly revise the decrease of the migration of MSCs and the expression of CXCR4 mRNA caused by CXCR4-siRNA. Conclusion: LA may improve the migration ability of MSCs through increasing CXCR4 expression therapy enhancing their therapeutic activity.

11.
Transl Androl Urol ; 10(10): 3826-3836, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34804825

RESUMO

Background: At present, the low risk of bladder cancer (BCa)-specific death has allowed for investigation into treatment-related cardiotoxicity. To aid clinicians in selecting appropriate cardiovascular disease screening strategies and interventions, this study explored the heart-specific mortality and prognostic factors of patients with BCa after radical cystectomy (RC), radiotherapy (RT), or chemotherapy (CT), and compared their long-term heart-specific mortality with that of the general male population. Methods: We identified three different treatments for BCa patients from the Surveillance, Epidemiology, and End Results (SEER) database: RC, RT, and CT. Patients were included from 2000 to 2012 and followed through 2015. A cumulative mortality curve and competitive risk regression model were applied to evaluate the prognostic factors of heart-specific mortality, and standardized mortality ratios (SMRs) were calculated. Results: Of 39,500 men, 30.3%, 18.8%, and 50.9% received RC, RT, and CT, respectively. For patients with a survival period of less than 50 months, tumor-specific death exhibited a rapidly increasing trend, which subsequently flatlined. However, the rates heart-specific mortality and other causes exhibited a tendency to increase stably. The heart-specific and all-cause mortality rates of patients in any age group treated with the three abovementioned strategies were higher than those of the general population. The heart-specific mortality of patients with carcinoma in situ treated with RC and CT exceeded their all-cause mortality, while that of other tumor stages did not. The risks of heart-specific [sub-distribution hazard ratio (SHR) =1.38; 95% confidence interval (CI): 1.22-1.57] and tumor-specific (SHR =1.68; 95% CI: 1.60-1.77) deaths in patients who received RT were higher than those of patients who underwent CT. Conclusions: The risks of heart-specific and tumor-specific deaths in patients who received RT were higher than those of the RC and CT groups, especially in patients over 65 years of age who received RT.

12.
Neurobiol Learn Mem ; : 107557, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34808337

RESUMO

The hippocampus, retrosplenial cortex and anterior thalamus are key components of a neural circuit known to be involved in a variety of memory functions, including spatial, contextual and episodic memory. In this review, we focus on the role of this circuit in contextual memory processes. The background environment, or context, is a powerful cue for memory retrieval, and neural representations of the context provide a mechanism for efficiently retrieving relevant memories while avoiding interference from memories that belong to other contexts. Data from experimental lesions and neural manipulation techniques indicate that each of these regions is critical for contextual memory. Neurophysiological evidence from the hippocampus and retrosplenial cortex suggest that contextual information is represented within this circuit by population-level neural firing patterns that reliably differentiate each context a subject encounters. These findings indicate that encoding contextual information to support context-dependent memory retrieval is a key function of this circuit.

13.
Opt Express ; 29(23): 37747-37758, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34808841

RESUMO

Non-collinear stimulated Brillouin scattering (SBS) amplification can obtain high peak power Stokes output while ensuring the stability, but the frequency mismatch reduces the energy conversion efficiency of the system. In this paper, a dual-frequency pulse laser based on acousto-optic crystal modulation is designed. The output pulse pair can be used as pump and Stokes light, respectively, which realizes the active frequency matching of the gain medium Brillouin frequency shift during the SBS amplification process and helps to maintain ideal energy conversion efficiency. The dual-frequency laser finally produced a laser pulse pair with a pulse width adjustment range of 100 ps-50 ns, a frequency shift range of 0 GHz-2 GHz, and the polarization extinction ratio (PER) reaches 20.82dB.

14.
Ann Transl Med ; 9(18): 1440, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733992

RESUMO

Background: Bladder cancer is one of the most common carcinomas and it brings about huge social economic burden. There is not a reliable way to predict the prognosis of bladder patients. We develop the nomogram to predict the prognosis of bladder cancer patients. Methods: A total of 127 bladder cancer patients after radical cystectomy were studied retrospectively. Their clinicopathological data were collected for statistical analysis. Results: The level of albumin/globulin ratio (AGR), C-reactive protein/albumin ratio (CAR), neutrophil to lymphocyte ratio (NLR) and platelet to lymphocyte ratio (PLR) associated with pathological and hematological parameters like T stage and hemoglobin. Furthermore, the AGR was associated with overall survival (OS) and CAR, NLR, and PLR were associated with both OS and progression-free survival (PFS) (P<0.05). The multivariate analysis revealed that tobacco smoking, tumor T stage, M stage, NLR, CAR, and AGR were all independent predictors for OS of patients and tobacco smoking, tumor T stage, NLR, CAR, and AGR were independent predictors for PFS of patients. In addition, AGR, CAR, and NLR, as well as, the clinicopathological parameters in the development of nomograms with a C index of 0.901 (95% CI: 0.505-1.269) for OS, and 0.807 (95% CI: 0.755-0.858) for PFS. The nomograms were able to provide a prognosis of the OS with the area under the curve (AUC) =0.86. Further, tests assessed the PFS with the AUC =0.84. Conclusions: This study demonstrates that the nomograms of the inflammatory biomarkers were able to predict prognosis of bladder cancer patients after radical cystectomy.

15.
Sensors (Basel) ; 21(21)2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34770569

RESUMO

Copper elbows are an important product in industry. They are used to connect pipes for transferring gas, oil, and liquids. Defective copper elbows can lead to serious industrial accidents. In this paper, a novel model named YOT-Net (YOLOv3 combined triplet loss network) is proposed to automatically detect defective copper elbows. To increase the defect detection accuracy, triplet loss function is employed in YOT-Net. The triplet loss function is introduced into the loss module of YOT-Net, which utilizes image similarity to enhance feature extraction ability. The proposed method of YOT-Net shows outstanding performance in copper elbow surface defect detection.


Assuntos
Algoritmos , Cobre , Cotovelo
16.
Dev Comp Immunol ; 128: 104311, 2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34752843

RESUMO

NOD-like receptors (NLRs) are a kind of pattern recognition receptors, which are vital for detection of pathogen-associated molecular patterns (PAMPs) or damage-associated molecular patterns (DAMPs) and then trigger downstream immune responses in vertebrates. Although many NLR like genes have been identified in invertebrates in recent years, knowledge about their immune functions is still very limited. In the present study, a NLR like gene, designated as LvNLRPL1, was identified in Litopenaeus vannamei. It was widely expressed in multiple tissues and responsive to the infection of Vibrio parahaemolyticus. Knockdown of LvNLRPL1 could accelerate the proliferation of Vibrio in hepatopancreas and increase the mortality rate of shrimp after Vibrio infection. Meanwhile, knockdown of LvNLRPL1 also up-regulated the expression of Caspase 2, 3 and 5 in hemocytes, which caused apoptosis of more hemocytes. These results indicated that LvNLRPL1 played important immune functions in shrimp during Vibrio infection through regulating the apoptosis of hemocytes in shrimp. To our knowledge, this is the first time to reveal the immune function of a NLR like gene in crustaceans.

17.
Sci Total Environ ; : 151540, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34767892

RESUMO

Flower is an essential element in the human lifestyle but its role in disseminating antimicrobial resistance (AMR) between the environment and humans is unclear. In this study, we screened fresh flowers (Lilium spp.) collected from planting bases, market and florists in Guangzhou China aiming to investigate the prevalence of AMR genes, particularly cfr, optrA and poxtA mediating resistance to linezolid, a first-line drug for the treatment of different Gram-positive bacterial infections. We found 223 Enterococcus isolates consisting of Enterococcus faecalis, Enterococcus faecium and Enterococcus mundtii, and >50% of these isolates exhibited multiple-drug resistance. Additionally, 31 optrA-positive Enterococcus including 22 E. faecalis and 9 E. mundtii strains were recovered, however cfr and poxtA were not detected. The 22 E. faecalis strains were belonged to 7 Multilocus sequence types in which ST202 and ST376 were predominant and 9 E. mundtii strains from the same plantation bases were divided into three PFGE groups. Genetically, the majority of optrA were located on the chromosome and shared similar insertion sites and transpositions mediated by Tn554 family members. Plasmid-bearing optrA were identified in 6 E. faecalis strains where IS1216 family played key roles in horizontal transfer of optrA. These findings emphasize that the prevalence of drug resistant Enterococcus in fresh flowers is a latent danger and increases the risk of AMR dissemination to humans from the environment.

18.
J Exp Clin Cancer Res ; 40(1): 371, 2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34801071

RESUMO

BACKGROUND: Brain metastasis (BM) is thought to be related to the mortality and poor prognosis of non-small cell lung cancer (NSCLC). Despite promising development of NSCLC treatment, the treatment of NSCLC BM is still not optimistic due to the existence of the blood-brain barrier (BBB) that prevent drug penetration, as well as the short median survival time of the patients left for treatment. In this context, further development of quick and effective pre-clinical models is needed in NSCLC BM treatment. Here, we report a model system using zebrafish to promote the development of drugs for patients with NSCLC BM. METHODS: Three different NSCLC cell lines (H1975, A549 and H1299) were used to establish zebrafish BM models. The embryo age and cell number for injection were first optimized. Metastatic cells were observed in the brain blood vessels of zebrafish and were verified by hematoxylin-eosin (HE) staining. Then, the metastasis potentials of H1975 and A549 with manipulated microRNA-330-3p (miR-330-3p) expression were also investigated. Finally, sensitivities of H1975 and A549 to osimertinib and gefitinib were tested. RESULTS: This zebrafish BM model could distinguish NSCLC cell lines with different BM potential. Over-expressed miR-330-p significantly improved the BM potential of the A549 cells while knockdown miR-330-p reduced the BM ability of the H1975 cells. Both osimertinib and gefitinib showed inhibition effect in zebrafish BM model with the inhibition rate higher than 50 %. H1975 cell showed much higher sensitivity to osimertinib rather than gefitinib both in vivo and in vitro. CONCLUSIONS: We established zebrafish brain metastasis model for studying mechanism and treatment of NSCLC BM. This study provided a useful model for NSCLC brain metastasis that could be used to study the mechanism that drive NSCLC cells to the brain as well as identify potential therapeutic options.

19.
Pak J Pharm Sci ; 34(5): 1715-1722, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34803007

RESUMO

Ranitidine hydrochloride (RH) resinates were prepared by bath method using a highly acidic cation-exchange resin as the carrier. The drug-resinates combination pattern was characterized by DSC and X-ray diffraction. The influences of the types of the ion-exchange resin, initial RH concentration and the reaction temperature on the process of ion exchange were investigated. Three empirical kinetics models and thermodynamics equations were studied to the ion exchange process under different temperatures. The results showed that RH combined with ion-exchange resin not simple physical mixture but by ion bond, and the rate of ion exchange increased on increasing the initial drug concentration and reducing the temperature the resin. The in vitro drug release test showed that the release process was affected by the kind of countra-ion, ionic strength and temperature. Thermodynamics results showed that the ion exchange reaction between RH and cation-exchange resin was exothermic (ΔHθr,m< <0), and the drug release process could preferably be fitted with the first order equation. In conclusion, RH resinates were prepared by the bath method with strongly acidic cation-exchange (Amberlite® IRP69) with 5 mg/mL RH solution(100mL) stirred at 298K for 1h. Drug release from resinates was fitted with Viswanathan equation, and to achieve obvious sustained-release effect, the RH-resin complex should be further coated with a semipermeable membrane.

20.
Nat Commun ; 12(1): 6525, 2021 11 11.
Artigo em Inglês | MEDLINE | ID: mdl-34764271

RESUMO

The cereal endosperm is a major factor determining seed size and shape. However, the molecular mechanisms of endosperm development are not fully understood. Long noncoding RNAs (lncRNAs) function in various biological processes. Here we show a lncRNA, MISSEN, that plays an essential role in early endosperm development in rice (Oryza sativa). MISSEN is a parent-of-origin lncRNA expressed in endosperm, and negatively regulates endosperm development, leading to a prominent dent and bulge in the seed. Mechanistically, MISSEN functions through hijacking a helicase family protein (HeFP) to regulate tubulin function during endosperm nucleus division and endosperm cellularization, resulting in abnormal cytoskeletal polymerization. Finally, we revealed that the expression of MISSEN is inhibited by histone H3 lysine 27 trimethylation (H3K27me3) modification after pollination. Therefore, MISSEN is the first lncRNA identified as a regulator in endosperm development, highlighting the potential applications in rice breeding.

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