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1.
EBioMedicine ; 51: 102621, 2020 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-31901869

RESUMO

BACKGROUND: Approximately 1 in 33 newborns is affected by congenital anomalies worldwide. We aimed to develop a practical model for identifying infants with a high risk of congenital cataracts (CCs), which is the leading cause of avoidable childhood blindness. METHODS: This case-control study was performed in the Zhongshan Ophthalmic Center and involved 2005 subjects, including 1274 children with CCs and 731 healthy controls. The CC identification models were established based on birth conditions, family medical history, and family environmental factors using the random forest (RF) and adaptive boosting methods (trained by 1129 CC cases and 609 healthy controls), which were tested by internal 4-fold cross-validation and external validation (145 CC cases and 122 healthy controls). The models were also tested using 4 datasets with gradually reduced proportions of CC patients (bilateral cases) to validate their performance in an approximate simulation of a clinical environment with a relatively low disease prevalence. FINDINGS: The CC identification models showed high discrimination in both the 4-fold cross validation (area under the curve (AUC)=0.91 [95% confidence interval: 0.88-0.94] in bilateral cases; 0.82 [0.77-0.89] in unilateral cases) and external validation (AUC=0.93±0.05 in bilateral cases; 0.86±0.01 in unilateral cases), and achieved stable performance in the clinical tests (AUC=0.94-0.96 in the four subgroups by RF). Furthermore, family history of CC, low parental education level, and comorbidity were identified as the top three most relevant factors to both bilateral and unilateral CC diagnosis. INTERPRETATION: Our CC identification models can accurately discriminate CC patients from healthy children and have the potential to serve as a complementary screening procedure, especially in undeveloped and remote areas.

2.
Aging (Albany NY) ; 12(1): 784-807, 2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31927532

RESUMO

C-C motif chemokine ligand 14 (CCL14) is a chemokine promoting the activation of immune cells. However, the relationship between CCL14 expression, tumor immunity, and prognosis in Hepatocellular Carcinoma (HCC) remain unclear. CCL14 expression and its influence on tumor prognosis were analyzed by the ONCOMINE, Tumor Immune Estimation Resource (TIMER) and Kaplan-Meier plotter. The relationship between CCL14 expression and tumor immunity were analyzed by TIMER and Gene Expression Profiling Interactive Analysis (GEPIA). CCL14 expression was significantly lower in several human cancers, including HCC, than in corresponding normal tissues. CCL14 expression in HCC tissues correlated with prognosis. Low CCL14 expression associated with poorer overall survival, disease-specific survival, progression-free survival, and relapse-free survival in multiple cohorts of HCC patients, particularly at early disease stages (stage 1+2 or grade 2). CCL14 showed strong correlation with tumor-infiltrating B cells, CD4+ and CD8+ T cells, macrophages, neutrophils, and dendritic cells. CCL14 expression in HCC negatively correlated with expression of several immune cell markers, including exhausted T cell markers, PD-1, TIM-3 and CTLA-4, suggesting its role in regulating tumor immunity. These findings demonstrate that CCL14 is a potential prognostic biomarker that determines cancer progression and correlated with tumor immune cells infiltration in HCC.

3.
Theranostics ; 10(2): 657-670, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31903143

RESUMO

Rationale: Nanomaterials capable of specifically interacting with proteins are very important for protein storage and vaccine delivery. Supramolecular hydrogels based on peptides have emerged as promising vaccine adjuvants because of their good compatibility, ease of antigen incorporation and display, and efficiency in activating immune responses. Methods: We synthesized a self-assembling peptide (Fbp-GDFDFDYDK(γE)2-NH2, Comp. 1 ) serving as a supramolecular protein chaperone for protein antigen delivery. The gelation was triggered by simply mixing Comp. 1 and proteins. The vaccine adjuvant potential of Comp. 1 was demonstrated by using two protein antigens, ovalbumin (OVA) and hepatitis B surface antigen (HBsAg). Results: The peptide derivative Comp. 1 exhibited high protein binding capacity. Upon contacting proteins, Comp. 1 rapidly formed coassembled nanofibers/hydrogels with the proteins, which greatly delayed the release of protein antigens. Our supramolecular protein chaperone significantly stimulated specific antibody titers by assisting protein delivery to antigen-presenting cells, promoting dendritic cell (DC) maturation, prolonging antigen accumulation and retention in the lymph nodes, and eliciting the secretion of cytokines. Most importantly, our supramolecular protein chaperone strongly stimulated the cellular immune response and significantly retarded tumor growth. Conclusion: Our study demonstrated the great potential of the supramolecular protein chaperone in protein storage and delivery, vaccine production and tumor immunotherapy.

4.
Artigo em Inglês | MEDLINE | ID: mdl-31930756

RESUMO

The emergence of ceria (CeO2) as an efficient catalyst for selective hydrogenation of alkynes has attracted great attention. Intensive research efforts have been devoted to the understanding of the underlying catalytic mechanism, in particular to H2/CeO2 interaction. In this work, we show that the adsorption of propyne (C3H4) on ceria, another key aspect of the propyne-to-propene hydrogenation reaction, strongly depends on the ceria surface reduction, surface hydroxylation, and water. Through the combination of infrared reflection absorption spectroscopy (IRAS) and density functional theory (DFT) calculations, the dissociation of propyne and the formation of methylacetylide (CH3CC-) have been identified. We demonstrate that propyne adsopts a heterolytic dissociation on the reduced ceria surface by forming a methylacetylide ion onto the oxygen vacancy site and transferring a proton to the nearby oxygen site (OH group), while water molecule that competes with the chemisorbed methylacetylide on the vacancy site assists the homolytic dissociation pathway via rebounding this methylacetylide to the nearby oxygen site.

5.
Analyst ; 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-31934695

RESUMO

A low-cost tap water fingerprinting technique was evaluated using the coffee-ring effect, a phenomenon by which tap water droplets leave distinguishable "fingerprint" residue patterns after water evaporates. Tap waters from communities across southern Michigan dried on aluminum and photographed with a cell phone camera and 30× loupe produced unique and reproducible images. A convolutional neural network (CNN) model was trained using the images from the Michigan tap waters, and despite the small size of the image dataset, the model assigned images into groups with similar water chemistry with 80% accuracy. Synthetic solutions containing only the majority species measured in Detroit, Lansing, and Michigan State University tap waters did not display the same residue patterns as collected waters; thus, the lower concentration species also influence the tap water "fingerprint". Residue pattern images from salt mixtures with an array of sodium, calcium, magnesium, chloride, bicarbonate, and sulfate concentrations were analyzed by measuring features observed in the photographs as well as using principal component analysis (PCA) on the image files and particles measurements. These analyses together highlighted differences in the residue patterns associated with the water chemistry in the sample. The results of these experiments suggest that the unique and reproducible residue patterns of tap water samples that can be imaged with a cell phone camera and a loupe contain a wealth of information about the overall composition of the tap water, and thus, the phenomenon should be further explored for potential use in low-cost tap water fingerprinting.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31897660

RESUMO

Immune checkpoint inhibitors (ICIs) represent a major breakthrough for cancer treatment. However, evidence regarding the use of ICIs in pancreatic cancer (PC) remained scarce. To assess the efficacy and safety of ICIs plus chemotherapy, patients with advanced PC were retrospectively recruited and were treated with either chemotherapy alone or chemotherapy plus ICIs. Patients previously treated with any agents targeting T-cell co-stimulation or checkpoint pathways were excluded. The primary outcome was overall survival (OS). The secondary outcomes were progression-free survival (PFS), overall response rate (ORR) and safety. In total, 58 patients were included (combination, n = 22; chemotherapy, n = 36). The combination group showed a significantly longer OS than the chemotherapy group [median, 18.1 vs 6.1 months, hazard ratio (HR) 0.46 (0.23-0.90), P = 0.021]. The median PFSs were 3.2 months in the combination group and 2.0 months in the chemotherapy group [HR 0.57 (0.32-0.99), P = 0.041]. The combination group and the chemotherapy group had similar ORRs (18.2% vs 19.4%, P = 0.906). All patients who achieved a partial response received a doublet chemotherapy regimen regardless of co-treatment with ICIs. Grade 3 or higher adverse events occurred in 31.8% of the patients in the combination group and in 16.9% of those receiving chemotherapy. Although the incidence of serious treatment-related adverse events was higher in the combination group than in the chemotherapy group, the difference was not significant (P = 0.183). Our findings suggest that the combination of ICIs with chemotherapy is both effective and tolerable for advanced PC. ICIs combined with a doublet chemotherapy regimen might be a preferable choice.

7.
Cell Signal ; 68: 109536, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31927036

RESUMO

Tamoxifen (TAM) is frequently used to treat patients with estrogen receptor-positive (ER+) breast cancer; however, the development of endocrine resistance represents a major impediment for successful treatment. Recent studies have demonstrated that long non-coding RNAs (lncRNAs) may serve critical roles in regulating endocrine resistance in breast cancer. In the present study, it was determined that the expression of lncRNA in nonhomologous end joining pathway 1 (LINP1) was increased in tamoxifen-resistant breast cancer cells, and that LINP1 knockdown significantly attenuated the tamoxifen resistance and viability of tamoxifen-resistant breast cancer cells in vitro and in vivo. LINP1 knockdown increased apoptosis in cells following treatment with tamoxifen. Furthermore, LINP1 overexpression resulted in increased cell mobility by regulating the EMT process. Mechanistically, LINP1 is a direct target of ER-mediated transcriptional repression, and both tamoxifen treatment and hormone deprivation increased the expression of LINP1. LINP1 overexpression was associated with downregulation of the levels of ER protein and attenuated the estrogen response, which is a pivotal contributing factor to anti-estrogen resistance. Taken together, the present study highlights the pivotal role of LINP1 in tamoxifen resistance, which may serve as a potential target to improve the effectiveness and efficacy of tamoxifen treatment in breast cancer.

8.
J Food Biochem ; : e13141, 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31899549

RESUMO

"Golden delicious" apples were dipped in 100 mg/L acibenzolar-S-methyl (ASM) to investigate the fruit quality and softening during 12 days of storage. Weight loss, flesh firmness, ethylene release, respiratory rate, content of total soluble solids and titratable acid, the activity of pectinase, cellulase, and ß-glucosidase, and water-insoluble pectin and water-soluble pectin contents were investigated. The results demonstrated that ASM treatment inhibited ethylene release and respiratory rate, reduced titratable acidity, and enhanced total soluble solids content in apples. Moreover, application of ASM suppressed the reduction of flesh firmness, activity of pectin methylesterase, and polygalacturonase. Cellulase, ß-glucosidase, and degradation of protopectin in apple fruit were also suppressed by ASM treatment during storage. In conclusion, ASM could maintain fruit quality by regulating cell wall-degrading enzymes during storage. PRACTICAL APPLICATIONS: Application of acibenzolar-S-methyl after harvest has the potential of delaying fruit softening by regulating cell wall-degrading enzymes, thus retain fruit quality.

9.
Biosci Rep ; 40(1)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31868207

RESUMO

Connexins are the membrane proteins that form high-conductance plasma membrane channels and are the important constituents of gap junctions and hemichannels. Among different types of connexins, connexin 43 is the most widely expressed and studied gap junction proteins in astrocytes. Due to the key involvement of astrocytes in memory impairment and abundant expression of connexins in astrocytes, astroglial connexins have been projected as key therapeutic targets for Alzheimer's disease. On the other hand, the role of connexin gap junctions and hemichannels in memory formation and consolidation has also been reported. Moreover, deletion of these proteins and loss of gap junction communication result in loss of short-term spatial memory. Accordingly, both memory formation and memory deteriorating functions of astrocytes-located connexins have been documented. Physiologically expressed connexins may be involved in the memory formation, while pathologically increased expression of connexins with consequent excessive activation of astrocytes may induce neuronal injury and cognitive decline. The present review describes the memory formation as well as memory deteriorating functions of astroglial connexins in memory disorders of different etiology with possible mechanisms.

10.
J Comput Chem ; 41(1): 6-13, 2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31568571

RESUMO

The elementometalation process is a fundamental chemical step in several catalytic cycles. In this work, density functional theory computations have elucidated the detailed elementometalation mechanism of activated alkyne RCCR(RCO2 Me) by Cp2 TaH3 and rationalized the selectivity in experimental findings. The calculated results show that in the formation process of (E)-olefin monohydride((E)-Pro), the Gibbs free energy barrier is low and the entire reaction is spontaneous and exothermic; thus, (E)-Pro can be formed easily. The formation of (Z)-η2 -olefin monohydride complex ((Z)-Pro) is difficult due to its high Gibbs free energy barrier. The formation process (E)-Pro consists of the following five steps: hydride H1-shift, conformational isomerism 1, hydride H2-shift, conformational isomerism 2, and olefin coordination process. Topological analysis shows that there is a five-membered ring plane structure in the reaction pathway and that the final product (E)-Pro belongs to a typical η2 -olefin monohydride complex. Our calculated results provide an explanation for experimental observations and useful insights for further development of olefin functionalization. © 2019 Wiley Periodicals, Inc.

11.
Dent Traumatol ; 2019 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-31797525

RESUMO

BACKGROUND/AIMS: Lacerations of the oral mucosa and fractures of alveolar processes commonly occur in traumatic dental injuries (TDIs). Impaired wound healing and tissue regeneration have severe consequences on the quality of life. Bone marrow mesenchymal stem cells (BMMSCs) possess the ability of self-renewal, and multipotential differentiation. Treatment with low level sodium fluoride (NaF) has emerged as a promising approach to enhance wound repair. The aim of this study was to assess the effects of low level NaF on soft tissue healing and on the proliferation, migration and extracellular matrix synthesis of BMMSCs. MATERIAL AND METHODS: BMMSCs derived from mice were treated with 50 µM, 500 µM or 5 mM NaF for 12, 24 and 48 h and cell proliferation was assessed by the MTS assay. Cell motility was detected at 12 and 24 h by a wound healing assay, and osteoblastic differentiation for 21 days by 1% Alizarin-Red-S staining in 50 µM NaF-treated BMMSCs. Gene expression of Runx2 and Osteocalcin was evaluated by quantitative real-time PCR. An experimental rat skin wound model was employed, and levels of c-Myc, Ki67, Fibronectin and Vimentin were assessed by immunohistochemistry. RESULTS: There was a significant induction in the proliferation and migration of BMMSCs treated with 50 µM NaF. The expression of Ki67 and c-Myc protein was increased in tissues treated with 50 µM NaF and the expression of Fibronectin and Vimentin in the 50 µM NaF treated tissues was stimulated. Alizarin Red staining revealed enhanced mineralization in 50 µM NaF treated BMMSCs with increased expression of Runx2 and Osteocalcin, indicating their upregulated osteogenic differentiation. CONCLUSION: Low level NaF could promote soft tissue healing and hard tissue regeneration.

12.
Ultramicroscopy ; : 112912, 2019 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-31812451

RESUMO

The evolution of the scanning modules for scanning transmission electron microscopes (STEM) allows now to generate arbitrary scan pathways, an approach currently explored to improve acquisition speed and to reduce electron dose effects. In this work, we present the implementation of a random scan operating mode in STEM achieved at the hardware level via a custom scan control module. A pre-defined pattern with fully shuffled raster order is used to sample the entire region of interest. Subsampled random sparse images can then be extracted at successive time frames, to which suitable image reconstruction techniques can be applied. With respect to the conventional raster scan mode, this method permits to limit dose accumulation effects, but also to decouple the spatial and temporal information in hyperspectral images. We provide some proofs of concept of the flexibility of the random scan operating mode, presenting examples of its applications in different spectro-microscopy contexts: atomically-resolved elemental maps with electron energy loss spectroscopy and nanoscale-cathodoluminescence spectrum images. By employing adapted post-processing tools, it is demonstrated that the method allows to precisely track and correct for sample instabilities and to follow spectral diffusion with a high spatial resolution.

13.
Cancer Med ; 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31814295

RESUMO

BACKGROUND: The distant metastasis was the most predictive characters of poor prognosis for triple-negative breast cancer (TNBC). We aimed to evaluate the correlation between patient characters and preferential distant metastatic sites (DMS) and its effects on prognosis. METHODS: Using the 2010-2014 Surveillance, Epidemiology, and End Results Program (SEER) data, patients with TNBC were classified into eight histologic subtypes. Patient characters were compared using a chi-squared test. Logistic regression was used for identification of predictive factors. The log-rank testing was utilized with disease-specific survival (DSS) and overall survival (OS) as the primary outcomes. RESULTS: A total of 23 270 patients with TNBC were involved, including 1544 patients with distant metastatic cancer. Bone metastasis was diagnosed in 559 cases, brain metastasis in 124 cases, liver metastasis found in 369 cases and lung metastasis in 492 cases. Histologic subtypes including metaplastic breast carcinoma and invasive lobular carcinoma showed significant differences in preferential DMS compared with invasive ductal carcinoma. Furthermore, we found different histologic subtypes with specific DMS showed various prognosis. We also evaluated different DMS of specific histologic subtypes showed different prognosis. CONCLUSION: Certain histologic subtypes of breast cancer are associated with preferential DMS and prognosis; this knowledge may help to further understand the mechanism of breast cancer metastasis and to monitor the prognosis of patients with TNBC.

14.
Artigo em Inglês | MEDLINE | ID: mdl-31789034

RESUMO

The development of the information age has made resistive random access memory (RRAM) a critical nanoscale memristor device (MD). However, due to the randomness of the area formed by the conductive filaments (CFs), the RRAM MD still suffers from a problem of insufficient reliability. In this study, the memristor of Ag/ZrO2/WS2/Pt structure is proposed for the first time, and a layer of two-dimensional (2D) WS2 nanosheets was inserted into the MD to form 2D material and oxide double-layer MD (2DOMD) to improve the reliability of single-layer devices. The results indicate that the electrochemical metallization memory cell exhibits a highly stable memristive switching and concentrated ON- and OFF-state voltage distribution, high speed (∼10 ns), and robust endurance (>109 cycles). This result is superior to MDs with a single-layer ZrO2 or WS2 film because two layers have different ion transport rates, thereby limiting the rupture/rejuvenation of CFs to the bilayer interface region, which can greatly reduce the randomness of CFs in MDs. Moreover, we used the handwritten recognition dataset (i.e., the Modified National Institute of Standards and Technology (MNIST) database) for neuromorphic simulations. Furthermore, biosynaptic functions and plasticity, including spike-timing-dependent plasticity and paired-pulse facilitation, have been successfully achieved. By incorporating 2D materials and oxides into a double-layer MD, the practical application of RRAM MD can be significantly enhanced to facilitate the development of artificial synapses for brain-enhanced computing systems in the future.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31849021

RESUMO

BACKGROUND: There is limited evidence on the clinical and cost benefits of screening for atrial fibrillation (AF) with electrocardiogram (ECG) in asymptomatic adults. METHODS: We adapted a previously published Markov model to evaluate the clinical and economic impact of one-time screening for non-valvular AF (NVAF) with a single 12-lead ECG and a 14-day extended screening with a hand-held ECG device (Zenicor single-lead ECG, Z14) compared with no screening. Clinical events considered included ischemic stroke, systemic embolism, major bleeds, myocardial infarction, and death. Epidemiology and effectiveness data for extended screening were from the STROKESTOP study. Risks of clinical events in NVAF patients were derived from ARISTOTLE. Analyses were conducted from the perspective of a third-party payer, considering a population with undiagnosed NVAF, aged 75 years in the USA. Costs and utilities were discounted at a 3% annual rate. Parameter uncertainty was formally considered via deterministic and probabilistic sensitivity analyses (DSA and PSA). Structural uncertainty was assessed via scenario analyses. RESULTS: In a hypothetical cohort of 10,000 patients followed over their lifetimes, the number of additional AF diagnoses was 54 with 12-lead ECG and 255 with Z14 compared with no screening. Both screening strategies led to better health outcomes (ischemic strokes avoided: ECG 12-lead, 9.8 and Z14, 42.2; quality-adjusted life-years gained: ECG 12-lead, 31 and Z14, 131). Extended screening and one-time screening were cost effective compared with no screening at a willingness-to-pay (WTP) threshold of $100,000 per QALY gained ($58,728/QALY with ECG 12-lead and $47,949/QALY with Z14 in 2016 US dollars). ICERs remained below $100,000 per QALY in all DSA, most PSA runs, and in all scenario analyses except for a scenario assuming low anticoagulation persistence. CONCLUSIONS: Our analysis suggests that, screening the general population at age 75 years for NVAF is cost effective at a WTP threshold of $100,000. Both extended screening and one-time screening for NVAF are expected to provide health benefits at an acceptable cost.

16.
Acta Biomater ; 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31857259

RESUMO

Increasing evidence has suggested that paracrine mechanisms might be involved in the underlying mechanism of mesenchymal stem cells (MSCs) transplantation, and exosomes are an important component of this paracrine role. However, MSCs are usually exposed to normoxia (21% O2) in vitro but experience large differences in oxygen concentration in the body under hypoxia. Indeed, hypoxic precondition of MSCs can enhance their paracrine effects. The main purpose of this study was to determine whether exosomes derived from MSCs under hypoxia (Hypo-Exos) exhibit greater effects on bone fracture healing than those under normoxia (Exos). Using in vivo bone fracture model and in vitro experiments including cell proliferation assay, cell migration assay and so on, we confirmed that Hypo-Exos administration promoted angiogenesis, proliferation and migration to a greater extent when compared to Exos. Furthermore, utilizing a series in vitro and in vivo gain and loss of function experiments, we confirmed a functional role for exosomal miR-126 in the process of bone fracture healing. Meanwhile, we found that knockdown of hypoxia inducible factor 1 (HIF-1α) resulted in a significant decrease of miR-126 in MSCs and exosomes, thereby abolishing the effects of Hypo-Exos. In conclusion, our results demonstrated a mechanism by which Hypo-Exos promote bone fracture healing through exosomal miR-126. Moreover, hypoxia preconditioning mediated enhanced production of exosomal miR-126 through the activation of HIF-1α. Hypoxia preconditioning represents an effective and promising method for the optimization of the therapeutic actions of MSC-derived exosomes for bone fracture healing. STATEMENT OF SIGNIFICANCE: Studies have confirmed that transplantation of exosomes exhibit similar therapeutic effects and functional properties to directly-transplanted stem cells but have less significant adverse effects. However, during in vitro culture conditions, MSCs are usually exposed to normoxia (21% O2) which is very different to the oxygen concentrations found in the body under natural physiological conditions. Our results demonstrated a mechanism by which Hypo-Exos promote bone fracture healing through exosomal miR-126 and the SPRED1/Ras/Erk signaling pathway. Moreover, hypoxia preconditioning mediated enhanced production of exosomal miR-126 through the activation of HIF-1α. Hypoxia preconditioning represents an effective and promising method for the optimization of the therapeutic actions of MSC-derived exosomes for bone fracture healing.

17.
Reproduction ; 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31710595

RESUMO

Health risk of human exposure to microcystin-leucine arginine (MC-LR) has drawn more and more attention in recent years. In the present study, MC-LR inhibited miR-3473g expression of mouse granulosa cells both in vitro and in vivo. By dual-luciferase reporter assay, we confirmed miR-3473g is able to bind the 3'-untranslated region of steroidogenic acute regulatory protein (StAR) mRNA and suppress StAR expression. Thus, down-regulation of miR-3473g after MC-LR exposure led to StAR overexpression. Excessive StAR probably transported much more cholesterol into the inner membrane of the mitochondria and finally resulted in overproduction of progesterone. Our results revealed that MC-LR exposure was associated with premature luteinization of granulosa cells and may adversely affect women's fertility.

18.
J Hazard Mater ; : 121557, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31735469

RESUMO

Ceramic membranes allow a high filtration flux with a low fouling propensity. Direct filtration of municipal wastewater using flat-sheet ceramic membranes (FSCM) is an attractive and promising technology for wastewater treatment and resource recovery. Urgent need is to determine the fouling behavior of FSCM and its optimal cleaning strategy in direct filtration applications. This study was conducted on pre-coagulation of sewage with FeCl3 (20 mg Fe/L) or polyaluminum chloride (15 mg Al/L), followed by FSCM filtration at around 1.0 m/d (as high as 41.7 L/m2-h in flux). The results showed that the coagulation-FSCM filtration removed chemical oxygen demand and total phosphorus by up to 90.0% and 99.9%, respectively. The pollutants (organics and nutrients) in the sewage influent were concentrated into the sludge for potential resource recovery. Without pre-coagulation, foulants easily entered the membrane pores, causing rapid membrane fouling. Chemically enhanced coagulation greatly decreased the membrane fouling rate by aggregating various foulants into flocs. Fouled membranes were effectively renewed by physical means, such as water flushing and sonication, or a short period of chemical backwashing with NaOH, HCl or oxidizing agents. The study revealed the fouling mechanisms of FSCM in sewage filtration and developed effective cleaning strategies for its long-term operation.

19.
Int J Biol Macromol ; 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31756475

RESUMO

A neutral polysaccharide WM-NP-60 was successfully isolated and purified from a phytopathogenic fungus Sporisorium reilianum (Fries). The characteristics and potential antitumor activities of WM-NP-60 were studied. WM-NP-60 was a water-soluble polysaccharide. The molecular weight of WM-NP-60 was 15.6 kDa. The main chain of WM-NP-60 was composed of ß-1,6-D-Glcp and its side chains were ß-1,3-D-Glcp. The side chains bound to the main chain with glycosyl groups at the C-3 positions. Gal might be attached to the backbone as a side chain or bound to the linear ß-1,3-D-Glcp side chain. WM-NP-60 could inhibit the proliferation of HepG2 and SGC7901 cells in a dose-dependently manner. In addition, it was found that WM-NP-60 triggered the HepG2 and SGC7901 cell cycle arrest at the G1 phase and induced apoptosis of HepG2 and SGC7901 cells. Taken together, these results suggested that WM-NP-60 possessed a tumor-suppressive activity and might be regarded as a potential natural anti-tumor drug.

20.
Artigo em Inglês | MEDLINE | ID: mdl-31760543

RESUMO

In this study, the effect of biochar (BC) derived from Litchi chinensis Sonn. and its modification, including Ca-biochar (Ca-BC) and Fe-Mn-biochar (Fe-Mn-BC), on the transportation of oestrone (E1) in water and soil was investigated. Fe-Mn-BC showed better adsorption ability than other types of biochar (BC, Ca-BC) under different conditions (humic acid, pH, ionic strength) in an aqueous environment. The maximum mass of sorbent at 298 K increased from 1.12 mg g-1 (BC) to 4.18 mg g-1 (Fe-Mn-BC). Humic acid had a greater impact on aqueous E1 adsorption on these biochars than did the pH and ionic strength. Fe-Mn-BC as a soil amendment had a great control of E1 transport in soil, and no leachate of E1 was observed in the column experiment. E1 mobility showed strong retardation in amended soil with Ca-BC (Rf = 11.2) compared with raw soil (Rf = 7.1). These results suggested that Fe-Mn-BC was more effective in controlling E1 transportation, and Fe-Mn-BC could be used as an alternative and inexpensive adsorbent to reduce E1 contaminants from water and soil.

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