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Background: Transforming coniferous plantation into broadleaved or mixed broadleaved-coniferous plantations is the tendency of forest management strategies in subtropical China. However, the effects of this conversion on soil phosphorus (P) cycling microbial functional genes are still unknown. Methods: Soil samples were collected from 0-20, 20-40, and 40-60 cm (topsoil, middle layer, and subsoil, respectively) under coniferous Pinus massoniana (PM), broadleaved Erythrophleum fordii (EF), and their mixed (PM/EF) plantation in subtropical China. Used metagenomic sequencing to examine the alterations of relative abundances and molecular ecological network structure of soil P-cycling functional genes after the conversion of plantations. Results: The composition of P-cycling genes in the topsoil of PM stand was significantly different from that of PM/EF and EF stands (p < 0.05), and total phosphorus (TP) was the main factor causing this difference. After transforming PM plantation into EF plantation, the relative abundances of P solubilization and mineralization genes significantly increased in the topsoil and middle layer with the decrease of soil TP content. The abundances of P-starvation response regulation genes also significantly increased in the subsoil (p < 0.05), which may have been influenced by soil organic carbon (SOC). The dominant genes in all soil layers under three plantations were phoR, glpP, gcd, ppk, and ppx. Transforming PM into EF plantation apparently increased gcd abundance in the topsoil (p < 0.05), with TP and NO3 --N being the main influencing factors. After transforming PM into PM/EF plantations, the molecular ecological network structure of P-cycling genes was more complex; moreover, the key genes in the network were modified with the transformation of PM plantation. Conclusion: Transforming PM into EF plantation mainly improved the phosphate solubilizing potential of microorganisms at topsoil, while transforming PM into PM/EF plantation may have enhanced structural stability of microbial P-cycling genes react to environmental changes.
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OBJECTIVE: The purpose of this study was to evaluate the yield, viability, clinical safety, and efficacy of the stromal vascular fraction (SVF) separated with a new protocol with all clinical-grade drugs. MATERIALS AND METHODS: SVF cells were isolated from lipoaspirate obtained from 13 participants aged from 30 to 56 years by using a new clinical protocol and the laboratory protocol. The cell yield, viability, morphology, mesenchymal stem cell (MSC) surface marker expression, and differentiation abilities of the SVF cells harvested from the two protocols were compared. Furthermore, three related clinical trials were conducted to verify the safety and efficiency of SVF cells isolated by the new clinical protocol. RESULTS: There were no significant differences in the yield, viability, morphology, and differentiation potential of the SVFs isolated with the clinical protocol and laboratory protocol. Adipose-derived mesenchymal stem cell (ASC) surface marker expression, including that of CD14, CD31, CD44, CD90, CD105, and CD133, was consistent between the two protocols. Clinical trials have demonstrated the effectiveness of the SVF isolated with the new clinical protocol in improving skin grafting, promoting mechanical stretch-induced skin regeneration and improving facial skin texture. No complications occurred. CONCLUSION: SVF isolated by the new clinical protocol had a noninferior yield and viability to that of the SVF separated by the laboratory protocol. SVFs obtained by the new protocol can be safely and effectively applied to improve skin grafting, promote mechanical stretch-induced skin regeneration, and improve facial skin texture. TRIAL REGISTRATION: The trials were registered with the ClinicalTrials.gov (NCT03189628), the Chinese Clinical Trial Registry (ChiCTR2000039317), and the ClinicalTrials.gov (NCT02546882). All the three trials were not patient-funded trials. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Transplantation of adipose-derived stem cells (ASCs) is a promising option in the field of chronic wounds treatment. However, the effectiveness of ASCs therapies has been hampered by highly inflammatory environment in chronic wound areas. These problems could be partially circumvented using efficient approaches that boost the survival and anti-inflammatory capacity of transplanted ASCs. Here, by application of mechanical stretch (MS), we show that ASCs exhibits increased survival and immunoregulatory properties in vitro. MS triggers the secretion of macrophage colony stimulating factor (M-CSF) from ASCs, a chemokine that is linked to anti-inflammatory M2-like macrophages polarization. When the MS-ASCs were transplanted to chronic wounds, the wound area yields significantly faster closure rate and lower inflammatory mediators, largely due to macrophages polarization driven by transplanted MS-ASCs. Thus, our work shows that mechanical stretch can be harnessed to enhance ASCs transplantation efficiency in chronic wounds treatment.
Subject(s)
Adipose Tissue , Macrophages , Wound Healing , Wound Healing/physiology , Macrophages/metabolism , Animals , Adipose Tissue/cytology , Humans , Mice , Stress, Mechanical , Stem Cells/cytology , Stem Cells/metabolism , Cells, Cultured , Male , Macrophage Colony-Stimulating Factor/metabolism , Stem Cell Transplantation/methods , Inflammation/therapy , Mice, Inbred C57BLABSTRACT
Cancer vaccines hold great potential for clinical cancer treatment by eliciting T cell-mediated immunity. However, the limited numbers of antigen-presenting cells (APCs) at the injection sites, the insufficient tumor antigen phagocytosis by APCs, and the presence of a strong tumor immunosuppressive microenvironment severely compromise the efficacy of cancer vaccines. Trained innate immunity may promote tumor antigen-specific adaptive immunity. Here, a personalized cancer vaccine is developed by engineering the inactivated probiotic Escherichia coli Nissle 1917 to load tumor antigens and ß-glucan, a trained immunity inducer. After subcutaneous injection, the cancer vaccine delivering model antigen OVA (BG/OVA@EcN) is highly accumulated and phagocytosed by macrophages at the injection sites to induce trained immunity. The trained macrophages may recruit dendritic cells (DCs) to facilitate BG/OVA@EcN phagocytosis and the subsequent DC maturation and T cell activation. In addition, BG/OVA@EcN remarkably enhances the circulating trained monocytes/macrophages, promoting differentiation into M1-like macrophages in tumor tissues. BG/OVA@EcN generates strong prophylactic and therapeutic efficacy to inhibit tumor growth by inducing potent adaptive antitumor immunity and long-term immune memory. Importantly, the cancer vaccine delivering autologous tumor antigens efficiently prevents postoperative tumor recurrence. This platform offers a facile translatable strategy to efficiently integrate trained immunity and adaptive immunity for personalized cancer immunotherapy.
Subject(s)
Cancer Vaccines , Neoplasms , Probiotics , Humans , Trained Immunity , Dendritic Cells , Neoplasms/therapy , Antigens, Neoplasm , Lymphocyte Activation , Probiotics/therapeutic use , Tumor MicroenvironmentABSTRACT
Direct ascorbic acid fuel cells (DAAFCs) employ biocompatible ascorbic acid (AA) as fuel, allowing convenient storage, transportation, and fueling as well as avoiding fuel crossover. The AA oxidation reaction (AAOR) largely governs the performance of DAAFCs. However, AAOR electrocatalysts currently have low activity, and state-of-the-art ones are limited to carbon black. Herein, we report the synthesis of an unprecedented AAOR electrocatalyst comprising 3.9 ± 1.1 nm CeO2 nanoparticles evenly distributed on carbon black simply by the wet chemical precipitation of Ce(OH)3 and a subsequent heat treatment. The resultant CeO2/C shows a remarkable AAOR activity with a peak current density of 13.1 mA cm-2, which is 1.7 times of that of carbon black (7.67 mA cm-2). According to X-ray photoelectron spectroscopy (XPS), the surface Ce3+ of CeO2 appears to contribute to the AAOR activity. Furthermore, our density functional theory (DFT) calculation reveals that that the proton of the hydroxyl group of AA can easily migrate to the bridging O sites of CeO2, resulting in a faster AAOR with respect to the pristine carbon, -COOH, and -C=O sites of carbon. After an i-t test, CeO2/C loses 17.8% of its initial current density, which is much superior to that of carbon black. CeO2 can capture the electrons generated by the AAOR to protect the -COOH and -C=O sites from being reduced. Finally, DAAFCs fabricated with CeO2/C exhibit a remarkable power density of 41.3 mW cm-2, which is the highest among proton-exchange-membrane-based DAAFCs in the literature.
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Against the backdrop of low-carbon development, it is imperative to cultivate a modernized industrial system and new development model. Industrial collaborative agglomeration (ICA) between manufacturing and producer services may offer an opportunity to aid carbon reduction in this scenario. Using balanced panel data of China's 30 provinces and municipalities from 2008 to 2019, this paper attempts to investigate the influences of ICA on carbon emission efficiency (CEE), its heterogeneous effects, impact mechanisms, and spillover effects. Our main findings can be concluded as follows: (1) There is a U-shaped relationship between ICA and CEE; namely, ICA will inhibit first and then promote CEE. (2) The heterogeneity results further indicate that this U-shaped relationship is significant in the eastern area while there exists an inverted U-shaped relationship between ICA and CEE in the western area; however, the influence of ICA on CEE is not significant in the central area. (3) More deeply, the mechanism identification uncovers that industrial structure upgrading and green technological innovation are important channels through which ICA affects CEE. (4) Importantly, we unfold that ICA in the local area has spatial spillover effects; namely, it will influence CEE in neighboring areas, which also presents a U-shaped relationship. These findings provide not only new insights into understanding the environmental effects of ICA but also helpful inspiration for regional policymakers to scientifically formulate industrial development policies and effectively implement carbon emission control actions.
Subject(s)
Carbon , Climate , China , Commerce , Industrial Development , Economic DevelopmentABSTRACT
Aeschynanthussmaragdinus F.Wen & J.Q.Qin, a new species of Gesneriaceae from the monsoon rain forest in Mangbang township, Tengchong City, Yunnan Province, China, is described and illustrated here. It morphologically resembles A.chiritoides C.B.Clarke in size, shape and hairs on the leaf blades. But it can easily be distinguished from the latter by the green corolla limb with brownish-red to maroon lower lobes. At the same time, the hairs of the pedicel and calyx lobes, the length of the staminode and the size of the seed grain can also help distinguish both. It is provisionally assessed as Data Deficient (DD), according to the IUCN Red List Categories and Criteria, because field surveys for this new taxon have not been completed.
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The use of ordered catalyst layers, based on micro-/nanostructured arrays such as the ordered Nafion array, has demonstrated great potential in reducing catalyst loading and improving fuel cell performance. However, the size (diameter) of the basic unit of the most existing ordered Nafion arrays, such as Nafion pillar or cone, is typically limited to micron or submicron sizes. Such small sizes only provide a limited number of proton transfer channels and a small specific area for catalyst loading. In this work, the ordered Nafion array with a pillar diameter of only 40 nm (D40) was successfully prepared through optimization of the Nafion solvent, thermal annealing temperature, and stripping mode from the anode alumina oxide (AAO) template. The density of D40 is 2.7 × 1010 pillars/cm2, providing an abundance of proton transfer channels. Additionally, D40 has a specific area of up to 51.5 cm2/cm2, which offers a large area for catalyst loading. This, in turn, results in the interface between the catalyst layer and gas diffusion layer becoming closer. Consequently, the peak power densities of the fuel cells are 1.47 (array as anode) and 1.29 W/cm2 (array as cathode), which are 3.3 and 2.9 times of that without array, respectively. The catalyst loading is significantly reduced to 17.6 (array as anode) and 61.0 µg/cm2 (array as cathode). Thus, the nanosized Nafion array has been proven to have high fuel cell performance with low Pt catalyst loading. Moreover, this study also provides guidance for the design of a catalyst layer for water electrolysis and electrosynthesis.
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Catalyst coated membrane (CCM) is the core component of proton exchange membrane fuel cells and is routinely fabricated by spraying Pt/C slurries onto membrane, resulting in low activity and thick catalyst layer (CL, 5-10 µm) with an unaffordable Pt loading of 0.2-0.4 mg cm-2 and a large mass transfer resistance at cathode. Highly active ultrathin ultralow-Pt CL (UUCL) is urgently required, but remains rare. Herein, wet-chemical direct growth of UUCLs on both sides of membrane to achieve integrated ultrathin ultralow-Pt catalyst coated membranes (UUCCMs) with a cathodic CL thickness of 79.7 ± 15.0 nm and a Pt loading of 20.2 ± 1.6 µg cm-2 is reported. The key to this unique fabrication is the release of proton from membrane to regioselectively initiate the growth of interconnected Pd nanoneedle clusters array on membrane, followed by high-density deposition of Pt nanoparticles on Pd (Pt/Pd UUCLs). The single cell of UUCCMs exhibits the highest mass peak power density of 59.9 W mgPt,Cathode -1 in the literature. The exceptional activity originates from high electrochemically active surface area, remarkable oxygen reduction reaction activity closely correlated with strain, and electronic effect at Pt/Pd interface, as well as improved mass transfer and optimal water management.
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This study was designed to investigate the toxic metal (aluminum (Al), arsenic (As), chromium (Cr), cadmium (Cd), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)) concentrations in drinking water and different foodstuffs meat (pork, beef, and mutton), cereals (rice, flour, corn, millet), beans (cowpeas, tofu), potatoes (potato, sweet potato), solanaceous fruits (pepper, eggplant, bitter gourd, cucumber), vegetables (cabbage, cauliflower, spinach), and fruits (apples, watermelons, pears, grapes)) and then estimate the potential health risks of toxic metal consumption to local residents in industrial regions of northern Ningxia, China. As in drinking water, Cr in meat, Pb in cereals, Pb in beans, As and Pb in potatoes, Pb in solanaceous fruits, Cr and Ni in vegetables, and Ni and Pb in fruits were the most contaminated heavy metals in the corresponding food with over-standard rates of 16.7%, 12.5%, 5.1%, 60%, 50%, 50%, 38.2%, 44.4%, 44.4%, 31.8%, and 31.8%, respectively.The results of the deterministic assessment of health risks showed that the total noncarcinogenic risk value of dietary intake of toxic metals by the local population was 5.6106, indicating that toxic metals pose a high noncarcinogenic risk. The order of the non-carcinogenic risk is HIcereal (1.2104) > HIsolanaceous fruit (0.9134) > HIVegetables (0.8726) > HIFruit (0.8170) > HIMeat (0.7269) > HIDrinking water (0.6139) > HIBeans (0.2991) > HIPotatoes (0.1573). The total carcinogenic health risk from exposure to toxic metals through dietary intake was 9.98 × 10-4, indicating that the total cancer risk value of residents is beyond the acceptable range (10-4) under the current daily dietary exposure and implies a high risk of cancer. The order of the carcinogenic risk is RDrinking water (2.34 × 10-4) > RMeat (2.11 × 10-4) > Rsolanaceous fruit (1.89 × 10-4) > RFruit (1.88 × 10-4) > Rcereal (1.36 × 10-4) > RPotatoes (2.44 × 10-5) > RVegetables (1.51 × 10-5) > RBeans (0). The probabilistic assessment results showed that 98.83% of the population is exposed to severe noncarcinogenic risk and 87.02% is exposed to unacceptable carcinogenic risk. The sensitivity analysis showed that drinking water, local cereals, vegetables, and fruits were the major contributors to health risks. Our results indicated that the daily dietary exposure of residents in industrial regions of northern Ningxia poses a serious threat to human health, and it is suggested that relevant departments should strengthen monitoring and control of the current situation of toxic metal pollution in the environment and continue to pay attention and take measures to reduce the exposure of toxic metals in the diets of residents in this area.
Subject(s)
Arsenic , Drinking Water , Fabaceae , Metals, Heavy , Soil Pollutants , Animals , Cattle , Humans , Drinking Water/analysis , Lead/analysis , Soil Pollutants/analysis , Metals, Heavy/toxicity , Metals, Heavy/analysis , Diet , Arsenic/analysis , Vegetables , Chromium/toxicity , Chromium/analysis , Nickel/analysis , China , Edible Grain/chemistry , Risk Assessment , Environmental MonitoringABSTRACT
Eight potentially toxic elements (PTEs, including nickel (Ni), copper (Cu), zinc (Zn), arsenic (As), cadmium (Cd), lead (Pb), chromium (Cr), and mercury (Hg)) in Lycium barbarum L. (wolfberries) and the associated root soil from a genuine producing area were analyzed. The potential ecological risk of PTEs in the soil and the health risk of PTEs through wolfberry consumption were determined. Geostatistical methods were used to predict the PTE concentrations in the wolfberries and soil. Positive matrix factorization (PMF) was applied to identify the source of PTEs in the soil. The PTE concentrations in the soils were within the standard limits, and Cd in the wolfberries exceeded the standard limit at only one site. The bioconcentration factors (BCF) order for the different PTEs was Cd > Cu > 1 > Zn > Cr > As > Ni > Pb, indicating that Cd and Cu were highly accumulated in wolfberries. The multiple regression models for Ni, Cu, Zn, As, Pb, and Cr concentrations in the wolfberries exhibited good correlations (p < 0.1). The ecological risk for Hg in the soil was high, whereas the risks for the remaining PTEs were mostly medium or low. Health risks for inhabitants through wolfberry consumption were not obvious. The spatial distributions of the PTEs in the soil differed from the PTE concentrations in the wolfberries. Source identification results were in the order of natural source (48.2%) > industrial activity source (27.8%) > agricultural activity source (14.5%) > transportation source (9.5%). The present study can guide the site selection of wolfberry cultivation and ensure the safety of wolfberry products when considering PTE contamination.
Subject(s)
Arsenic , Lycium , Mercury , Metals, Heavy , Soil Pollutants , Soil , Metals, Heavy/toxicity , Metals, Heavy/analysis , Soil Pollutants/analysis , Environmental Monitoring/methods , Cadmium , Risk Assessment , Arsenic/analysis , Zinc , ChinaABSTRACT
Proton exchange membrane water electrolyzers (PEMWEs) are capable of mass-producing green hydrogen with renewable and wave-trough electricity, but confront the challenge of the lack of advanced electrocatalysts to accelerate sluggish oxygen evolution reaction (OER). Herein, we report the synthesis of ultrafine IrRu alloy nanoparticles (1.6 ± 0.3 nm) by coprecipitation of IrCl3, RuCl3, and HCOONa in water to allow Ir3+ and Ru3+ to be well dispersed and enclosed in the matrix of crystalline HCOONa, followed by heat treatment of HCOONa to reduce Ir3+ and Ru3+. Remarkably, the overpotential of IrRu toward acidic OER at 10 mA cm-2 is merely 230 and 194 mV at 51 and 204 µgIrRu cm-2, respectively. The high electrochemically active surface area (ECSA) of 577.1 m2 g-1 and high specific activity (SA) of 22.7 µA cm-2 at 1.45 V vs RHE would contribute to the exceptional OER activity. In addition, the electron transfer from Ir to Ru in IrRu should significantly boost the OER activity according to X-ray photoelectron spectroscopy (XPS). IrRu also shows an excellent stability during 10 h of a chronopotentiometry (CP) test at 10 mA cm-2. Eventually, the high OER activity of IrRu was verified in a PEMWE.
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STUDY DESIGN: Retrospective Cohort Study. OBJECTIVES: This study aimed to develop survival prediction models for spinal Ewing's sarcoma (EWS) based on machine learning (ML). METHODS: We extracted the SEER registry's clinical data of EWS diagnosed between 1975 and 2016. Three feature selection methods extracted clinical features. Four ML algorithms (Cox, random survival forest (RSF), CoxBoost, DeepCox) were trained to predict the overall survival (OS) and cancer-specific survival (CSS) of spinal EWS. The concordance index (C-index), integrated Brier score (IBS) and mean area under the curves (AUC) were used to assess the prediction performance of different ML models. The top initial ML models with best performance from each evaluation index (C-index, IBS and mean AUC) were finally stacked to ensemble models which were compared with the traditional TNM stage model by 3-/5-/10-year Receiver Operating Characteristic (ROC) curves and Decision Curve Analysis (DCA). RESULTS: A total of 741 patients with spinal EWS were identified. C-index, IBS and mean AUC for the final ensemble ML model in predicting OS were .693/0.158/0.829 during independent testing, while .719/0.171/0.819 in predicting CSS. The ensemble ML model also achieved an AUC of .705/0.747/0.851 for predicting 3-/5-/10-year OS during independent testing, while .734/0.779/0.830 for predicting 3-/5-/10-year CSS, both of which outperformed the traditional TNM stage. DCA curves also showed the advantages of the ensemble models over the traditional TNM stage. CONCLUSION: ML was an effective and promising technique in predicting survival of spinal EWS, and the ensemble models were superior to the traditional TNM stage model.
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The non-catalytic hydrosilylation reaction has much high activation energy due to large differences in the energy of HOMO-LUMO pairing and restriction of the orbital symmetry overlap. For Pt(0)-catalytic hydrosilylation, the electronic structure of Me3SiH has been modified by the oxidative addition of Pt(0). It not only narrows down the energy differences between the bonding orbitals but also improves the orbital overlap symmetry, leading to the effective decrease of the activation energy. The trouble for the Pt(0)-catalytic hydrosilylation is the formation of the majority of the Pt-containing intermediates. Because they are fallen into the deep potential-energy, the reductive eliminations are energetically prohibitive, which is the essence of Pt-contamination. The reductive elimination can be achieved with the ligand exchange method, and the energy barrier can be tuned by suitable ligands.
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PtCoRh nanorods with an average width of 1.6 ± 0.2 nm show an overpotential of 6.1 mV at 10 mA cm-2 toward acidic HER. The exceptional activity originates from a high electrochemically active surface area of 130.1 m2 gPt-1 and a unique Pt-H bond strength appropriately tuned by Co and Rh.
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Insufficient tumor accumulation and distribution of photosensitizers as well as low antitumor immunity severely restrict the therapeutic efficacy of photothermal therapy (PTT). Cancer-associated fibroblasts (CAFs) play a key role in tumor extracellular matrix (ECM) remodeling and immune evasion. Reshaping tumor microenvironment via CAF regulation might provide a potential approach for complete tumor elimination in combination with PTT. Here, tumor cell-derived microparticles co-delivering calcipotriol and Indocyanine green (Cal/ICG@MPs) are developed to modulate CAFs for improved PTT efficacy. Cal/ICG@MPs efficiently target tumor tissues and regulate CAFs to reduce tumor ECM, resulting in enhanced tumor accumulation and penetration of ICG to generate strong PTT efficacy and activate CD8+ T cell-mediated antitumor immunity. In addition, Cal/ICG@MPs-triggered CAF regulation enhances tumor infiltration of CD8+ T cells and ameliorates CAF-induced antigen-mediated activation-induced cell death of tumor-specific CD8+ T cells in response to PTT, eliciting long-term antitumor immune memory to inhibit tumor recurrence and metastasis. Our results support Cal/ICG@MPs as a promising drug to improve PTT efficacy in cancer treatment.
Subject(s)
Cancer-Associated Fibroblasts , Neoplasms , CD8-Positive T-Lymphocytes , Cell Line, Tumor , Humans , Indocyanine Green/pharmacology , Neoplasms/therapy , Photothermal Therapy , RecurrenceABSTRACT
The perioperative trauma-related platelet recruitment and activation severely affect tumor recurrence and metastasis. Therefore, efficiently killing residual tumor cells and simultaneously inhibiting platelet activation to block platelet-cancer cell interaction might be a promising strategy to prevent postoperative tumor recurrence and metastasis. Methods: Biodegradable PLGA electrospun nanofibrous films co-delivering doxorubicin-loaded tumor repopulating cell-derived microparticles (DOX-MPs) and aspirin (ASA) were developed as the implant materials (DOX-MPs/ASA@NF) for postoperative in-situ treatment. The characterization, cytotoxicity against tumor cells, inhibition in platelet activation-triggered proliferation, migration and metastasis of tumor cells and in vivo anti-recurrence and anti-metastasis activity induced by DOX-MPs/ASA@NF were systematically evaluated. Results: PLGA nanofibrous films facilitate the enhanced distribution of DOX-MPs as well as DOX-MPs and ASA release in a time-programmed manner within the tumor resection cavity. The released DOX-MPs efficiently kill the residual tumor cells, while ASA decreases platelet activation and inhibits platelet-promoted proliferation, migration and metastasis of tumor cells, resulting in the remarkable inhibition of postoperative tumor recurrence and metastasis. Conclusions: DOX-MPs/ASA@NF may be a promising candidate to prevent the recurrence and metastasis of resectable tumors.
Subject(s)
Nanofibers , Cell Line, Tumor , Doxorubicin/pharmacology , Humans , Neoplasm Recurrence, Local/drug therapy , Neoplasm Recurrence, Local/prevention & control , Neoplasm, Residual/drug therapy , Platelet Aggregation InhibitorsABSTRACT
The berries of Lycium barbarum L. (Goji) are widely used as a Chinese traditional herbal medicine and functional food because of their reported beneficial pharmacological effects. However, there are reports of Goji berries being contaminated by chemical residues that could pose a hazard to humans. In this study, samples of L. barbarum L. berries were collected from plantations in a genuine production area and supermarkets in Ningxia, China. The major hazardous chemicals, including pesticides (dichlorvos, omethoate, cypermethrin, fenvalerate, malathion, and deltamethrin) and metals (lead (Pb), cadmium (Cd), copper (Cu), nickel (Ni), zinc (Zn), and arsenic (As)), were quantified by gas chromatography and inductively coupled plasma-optical emission spectrometry. In addition, associated daily exposures and health risks were determined using deterministic and probabilistic assessments. The levels of five pesticides from the plantation samples were considerably lower than the maximum residue limits; only dichlorvos was detected in the supermarket samples, and deltamethrin was not detected in any samples. Cu, Zn, As, Pb, Ni and Cd were detected in samples from both sources. The hazard quotient values of individual hazardous chemicals and the hazard index of combined hazardous chemicals were considerably less than 1, indicating the absence of a non-carcinogenic effect of hazardous chemical exposures through Goji berry consumption. The R value of As was much less than 10-6, which shows that consumption of the Goji berries had no obvious carcinogenic risks. The potentially harmful effects of the L. barbarum L. are more likely from berries obtained from plantations than those from supermarkets, and metal exposure is more dangerous than pesticide exposure. However, on the basis of our analysis, no population would be exposed hazardous chemicals exceeding existing standards, and the factors most affecting the health risk were exposure frequency and As content.