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1.
Carbohydr Polym ; 254: 117473, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33357927

RESUMO

To effectively and selectively remove toxic anionic dyes which are heavily discharged and to promote them recovery, a sustainable cellulose nanofiber/chitosan (CNF/CS) composite film was elaborately designed through a facile procedure. Based on the strong supporting effect of CNF and excellent compatibility between CNF and CS, the composite film presents low swelling and acid-proof properties, which can prevent the adsorption process from the disintegration of adsorbent. Moreover, the positive electrical property of CNF/CS film increases the discrepancy in adsorption capacities for anionic and cationic dyes. The maximum adsorption capacity of anionic methyl orange (MO) on CNF/CS film reaches 655.23 mg/g with a desirable recyclability. The adsorption behavior attributed to a physico-chemical and monolayer adsorption process. This work opens a new route for the development of eco-friendly and highly efficient adsorbents on selective removal and recycling of anionic dyes from wastewater.

2.
Bioresour Technol ; 303: 122949, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32058907

RESUMO

Reduction in water consumption and increase in ethanol concentration are two main challenges for bioethanol production from lignocellulosic materials. To address the two challenges, the aim of this work was to study the production of bioethanol from unwashed-pretreated rapeseed straw (RS) at high solid loading. RS pretreated with 1% (w w-1) H2SO4 at 160 °C for 10 min resulted in excellent digestibility and fermentability of pretreated RS. The unwashed-pretreated RS was subjected to presaccharification and fed-batch simultaneous saccharification and fermentation (P-FB-SSF) at a final solid loading of 22% (w w-1). Ethanol concentration and ethanol yield of 53.1 g L-1 (equivalent to 4.1% (w w-1) based on fermentation slurry) and 72.4% were obtained, respectively. In total, 92.1 g water g-1 ethanol was consumed, a much smaller amount than that observed with washing after pretreatment or fermentation performed at lower solid loading.


Assuntos
Brassica napus , Brassica rapa , Etanol , Fermentação , Hidrólise
3.
Polymers (Basel) ; 11(9)2019 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-31547358

RESUMO

An efficient electromagnetic interference (EMI) shielding paper with excellent water repellency and mechanical flexibility has been developed, by assembling silver nanowires (AgNWs) and hydrophobic inorganic ceramic on the cellulose paper, via a facile dip-coating preparation. Scanning electron microscope (SEM) observations confirmed that AgNWs were interconnected and densely coated on both sides of the cellulose fiber, which endows the as-prepared paper with high conductivity (33.69 S/cm in-plane direction) at a low AgNW area density of 0.13 mg/cm2. Owing to multiple reflections and scattering between the two outer highly conductive surfaces, the obtained composite presented a high EMI shielding effectiveness (EMI SE) of up to 46 dB against the X band, and ultrahigh specific EMI SE of 271.2 dB mm-1. Moreover, the prepared hydrophobic AgNW/cellulose (H-AgNW/cellulose) composite paper could also maintain high EMI SE and extraordinary waterproofness (water contact angle > 140°) by suffering dozens of bending tests or one thousand peeling tests. Overall, such a multifunctional paper might have practical applications in packaging conductive components and can be used as EMI shielding elements in advanced application areas, even under harsh conditions.

4.
Electron. j. biotechnol ; 41: 88-94, sept. 2019. tab, ilus, graf
Artigo em Inglês | LILACS | ID: biblio-1087247

RESUMO

Background: In industrial yeasts, selection and breeding for resistance to multiple stresses is a focus of current research. The objective of this study was to investigate the tolerance to multiple stresses of Saccharomyces cerevisiae obtained through an adaptive laboratory evolution strategy involving a repeated liquid nitrogen freeze­thaw process coupled with multi-stress shock selection. We also assessed the related resistance mechanisms and very high-gravity (VHG) bioethanol production of this strain. Results: Elite S. cerevisiae strain YF10-5, exhibiting improved VHG fermentation capacity and stress resistance to osmotic pressure and ethanol, was isolated following ten consecutive rounds of liquid nitrogen freeze­thaw treatment followed by plate screening under osmotic and ethanol stress. The ethanol yield of YF10-5 was 16% higher than that of the parent strain during 35% (w/v) glucose fermentation. Furthermore, there was upregulation of three genes (HSP26, HSP30, and HSP104) encoding heat-shock proteins involved in the stress response, one gene (TPS1) involved in the synthesis of trehalose, and three genes (ADH1, HXK1, and PFK1) involved in ethanol metabolism and intracellular trehalose accumulation in YF10-5 yeast cells, indicating increased stress tolerance and fermentative capacity. YF10-5 also showed excellent fermentation performance during the simultaneous saccharification and fermentation of VHG sweet potato mash, producing 13.40% (w/ v) ethanol, which corresponded to 93.95% of the theoretical ethanol yield. Conclusions: A multiple-stress-tolerant yeast clone was obtained using adaptive evolution by a freeze­thaw method coupled with stress shock selection. The selected robust yeast strain exhibits potential for bioethanol production through VHG fermentation.


Assuntos
Saccharomyces cerevisiae/fisiologia , Etanol/síntese química , Saccharomyces cerevisiae/genética , Seleção Genética , Estresse Fisiológico , Trealose , Leveduras , Cruzamento , Adaptação Fisiológica , Hipergravidade , Fermentação , Reação em Cadeia da Polimerase em Tempo Real , Congelamento , Proteínas de Choque Térmico
5.
ACS Appl Mater Interfaces ; 11(26): 23649-23658, 2019 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-31252483

RESUMO

Flexible strain sensors have attracted a great amount of attention for promising applications in next-generation artificially intelligent devices. However, it is difficult for conventional planar strain sensors to meet the requirements of miniature size and light weight for flexible electronics. Herein, a highly sensitive and stretchable fiber strain sensor with a millimeter diameter was innovatively fabricated by the capillary tube method to integrate silver nanowires (AgNWs) in polyurethane (PU) fibers. Scanning electron microscopy results demonstrate that AgNWs were embedded into the surface layer of PU fibers and formed completely conductive networks. The unique AgNW networks endow the PU/AgNW fibers with superior electrical conductivity of 3.1 S/cm, high elongation at break of 265%, wide response range of 43%, high gauge factor of 87.6 up to 22% strain, fast response time of 49 ms, and excellent reliability and stability. Such satisfactory stretchability and sensitivity is attributed to the combination of the highly stretchable PU matrix and the embedded architecture of the AgNW conductive network. Moreover, PU/AgNW fibers can be employed as wearable devices to detect various human motions and to drive light-emitting diodes at a lower voltage (2.7 V).

6.
Plant Mol Biol ; 98(4-5): 319-331, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30298427

RESUMO

The Lemnaceae, known as duckweed, the smallest flowering aquatic plant, shows promise as a plant bioreactor. For applying this potential plant bioreactor, establishing a stable and efficient genetic transformation system is necessary. The currently favored callus-based method for duckweed transformation is time consuming and genotype limited, as it requires callus culture and regeneration, which is inapplicable to many elite duckweed strains suitable for bioreactor exploitation. In this study, we attempted to establish a simple frond transformation system mediated by Agrobacterium tumefaciens for Lemna minor, one of the most widespread duckweed species in the world. To evaluate the feasibility of the new transformation system, the gene CYP710A11 was overexpressed to improve the yield of stigmasterol, which has multiple medicinal purposes. Three L. minor strains, ZH0055, D0158 and M0165, were transformed by both a conventional callus transformation system (CTS) and the simple frond transformation system (FTS). GUS staining, PCR, quantitative PCR and stigmasterol content detection showed that FTS can produce stable transgenic lines as well as CTS. Moreover, compared to CTS, FTS can avoid the genotype constraints of callus induction, thus saving at least half of the required processing time (CTS took 8-9 months while FTS took approximately 3 months in this study). Therefore, this transformation system is feasible in producing stable transgenic lines for a wide range of L. minor genotypes.


Assuntos
Agrobacterium tumefaciens/genética , Alismatales/genética , Engenharia Genética/métodos , Alismatales/metabolismo , Reatores Biológicos , Sistema Enzimático do Citocromo P-450/genética , Vetores Genéticos/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Reação em Cadeia da Polimerase , Estigmasterol/metabolismo , Transformação Genética/genética
7.
Oncogenesis ; 7(1): 12, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29362409

RESUMO

Cancer prognosis is poor for patients with blood-borne metastasis. Platelets are known to assist cancer cells in transmigrating through the endothelium, but ligands for the platelet-mediated cancer metastasis remain poorly defined. von Willebrand factor (vWF) is a major platelet ligand that has been widely used as a biomarker in cancer and associated inflammation. However, its functional role in cancer growth and metastasis is largely unknown. Here we report that gastric cancer cells from patients and cells from two well-established gastric cancer lines express vWF and secrete it into the circulation, upon which it rapidly becomes cell-bound to mediate cancer-cell aggregation and interaction with platelets and endothelial cells. The vWF-mediated homotypic and heterotypic cell-cell interactions promote the pulmonary graft of vWF-overexpressing gastric cancer BGC823 cells in a mouse model. The metastasis-promoting activity of vWF was blocked by antibodies against vWF and its platelet receptor GP Ibα. It was also reduced by an inhibitory siRNA that suppresses vWF expression. These findings demonstrate a causal role of cancer-cell-derived vWF in mediating gastric cancer metastasis and identify vWF as a new therapeutic target.

8.
BMC Gastroenterol ; 16(1): 57, 2016 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-27255554

RESUMO

BACKGROUND: Hexokinase-2 (HK2) and Beta2-adrenergic receptor (Beta2AR) are overexpressed in hepatocellular carcinoma (HCC) tissues and associated with poor prognosis. However, the synergistic effect of HK2 and Beta2AR in HCC prognosis is not elucidated. The present study aims to investigate the association between HK2 and Beta2AR expressions in HCC tissues, and to evaluate the synergistic effect of HK2 and Beta2AR in HCC prognosis. METHODS: Immunohistochemistry of HK2 and Beta2AR was performed on 155 paraffin embedded HCC samples retrieved from the archives of pathology department. Corresponding clinical data and prognostic data were collected through searching medical record systems, death registration systems and interviews with patient families. Spearman correlation test was performed to evaluate the association between HK2 and Beta2AR expression. Kaplan-Meier survival curves and Cox regressions were employed to evaluate HK2 and Beta2AR expression in HCC prognosis, respectively and synergistically. RESULTS: 109 of 155 HCC patients reached the death point, the survival time of HCC patients was 46.23 ± 31.01 months after curative surgical resections of HCC. Kaplan-Meier survival analysis showed that large tumor size (more than 5 cm) (hazard ratio (HR) = 8.42, 95 % confidence interval (CI) = 3.81-18.59, P < 0.0001), advanced TNM stage (III and IV stages) (HR = 2.09, 95%CI = 1.21-3.62, P < 0.001) and AFP more than 20 µg/L (HR = 1.49, 95%CI = 1.02-2.18, P = 0.0302) were predictors for poor prognosis. HK2 and Beta2AR positive expression was detected in 66 (42.58) and 122 (78.71 %) HCC samples respectively. In univariate analysis, HK2(+) (HR = 2.70, 95%CI = 1.76-4.15, P < 0.0001) and Beta2AR(+) (HR = 4.61, 96%CI = 3.14-6.76, P < 0.0001) were associated with poor prognosis. In multivariate analysis, HK2(+) (P < 0.0001) and Beta2AR(+) (P < 0.0001) were also associated with poor prognosis. HK2(+)/Beta2AR(+) in HCC samples had poorer prognosis compared with HK2(-)/Beta2AR(-) in both univariate analysis (HR = 4.69, 95%CI = 2.91-7.57, P < 0.0001) and multivariate analysis (P < 0.0001). HK2(+)/Beta2AR(+) in HCC samples had poorer prognosis compared with HK2(-)/Beta2AR(+) in both univariate analysis (HR = 1.76, 95%CI = 1.17-2.64, P = 0.003) and multivariate analysis (P = 0.004). CONCLUSION: HK2 and Beta2AR play important roles in HCC progression. HK2 and Beta2AR expression in HCC is correlated positively. Beta2AR may increase HCC invasion and metastasis in collaboration with HK2. HK2 and Beta2AR can predict HCC prognosis both independently and synergistically.


Assuntos
Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/cirurgia , Hexoquinase/metabolismo , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/cirurgia , Receptores Adrenérgicos beta 2/metabolismo , Carcinoma Hepatocelular/mortalidade , Sinergismo Farmacológico , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico
9.
Transl Neurosci ; 6(1): 157-161, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-28123799

RESUMO

BACKGROUND: Neuropsychiatric deficits can induce marked disability in patients with dementia and increase caregiver distress. Several studies have found that neuropsychiatric symptoms are common both in patients with Alzheimer's disease (AD) and patients with vascular dementia (VaD). However, there are few studies of the neuropsychiatric disturbances in large clinical samples of patients with mixed (cortical - subcortical) VaD from mainland China. This study aimed to investigate the neuropsychiatric symptoms in VaD patients in mainland China. METHODS: Eighty patients with mixed VaD for over 6 months duration, and their caregivers (VaD group), were recruited for interview in Zhongnan Hospital of Wuhan University, from June 2010 to June 2012. Eighty age- and sex-matched normal volunteers (control group) were interviewed at the same time. The Mini Mental State Examination (MMSE) and the Neuropsychiatric Inventory (NPI) were administered to the VaD patients, their caregivers, and normal volunteers. Group differences were analyzed using the unpaired t-test. RESULTS: The total mean scores of the NPI in the VaD group were higher than in the control group (P < 0.01). The subscale scores of NPI, including delusions, hallucinations, depression, apathy, irritability, agitation, aberrant motor behavior, and change in appetite were significantly higher in the VaD group than in the control group (P < 0.05-0.01). Compared with the mild VaD subgroup, the NPI subscale scores of apathy, irritability and total scores were significantly higher in the moderate VaD subgroup (P < 0.05-0.01); the NPI subscale scores of anxiety, apathy, irritability, and total scores were significantly higher in the severe VaD subgroup (P < 0.01). Compared with the moderate VaD subgroup, the NPI subscale scores of anxiety and apathy were significantly higher in the severe VaD subgroup (P < 0.05-0.01). CONCLUSIONS: Neuropsychiatric symptoms, such as hallucination, anxiety, apathy, irritability and aberrant action behavior, are common in patients with mixed VaD from mainland China; anxiety and apathy were more pronounced in the subgroup of severe VaD patients.

10.
Artigo em Inglês | MEDLINE | ID: mdl-24098169

RESUMO

In the title compound, [CdBr2(C8H8N2)2], the Cd(II) atom has a distorted tetra-hedral coordination formed by the two imino N atoms of two 2-methyl-benzimidazole ligands and two terminal bromide ligands. The Cd(II) atom is slightly out of the benzimidazole planes by 0.320 (3) and 0.210 (3) Å. The dihedral angle between the benzimidazole planes is 71.6 (2)°. In the crystal, mol-ecules are linked by N-H⋯Br hydrogen bonds into puckered layers parallel to (001).

11.
Biotechnol Biofuels ; 6(1): 72, 2013 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-23651472

RESUMO

BACKGROUND: Duckweed can thrive on anthropogenic wastewater and produce tremendous biomass production. Due to its relatively high starch and low lignin percentage, duckweed is a good candidate for bioethanol fermentation. Previous studies have observed that water devoid of nutrients is good for starch accumulation, but its molecular mechanism remains unrevealed. RESULTS: This study globally analyzed the response to nutrient starvation in order to investigate the starch accumulation in duckweed (Landoltia punctata). L. punctata was transferred from nutrient-rich solution to distilled water and sampled at different time points. Physiological measurements demonstrated that the activity of ADP-glucose pyrophosphorylase, the key enzyme of starch synthesis, as well as the starch percentage in duckweed, increased continuously under nutrient starvation. Samples collected at 0 h, 2 h and 24 h time points respectively were used for comparative gene expression analysis using RNA-Seq. A comprehensive transcriptome, comprising of 74,797 contigs, was constructed by a de novo assembly of the RNA-Seq reads. Gene expression profiling results showed that the expression of some transcripts encoding key enzymes involved in starch biosynthesis was up-regulated, while the expression of transcripts encoding enzymes involved in starch consumption were down-regulated, the expression of some photosynthesis-related transcripts were down-regulated during the first 24 h, and the expression of some transporter transcripts were up-regulated within the first 2 h. Very interestingly, most transcripts encoding key enzymes involved in flavonoid biosynthesis were highly expressed regardless of starvation, while transcripts encoding laccase, the last rate-limiting enzyme of lignifications, exhibited very low expression abundance in all three samples. CONCLUSION: Our study provides a comprehensive expression profiling of L. punctata under nutrient starvation, which indicates that nutrient starvation down-regulated the global metabolic status, redirects metabolic flux of fixed CO2 into starch synthesis branch resulting in starch accumulation in L. punctata.

12.
Biomed Pharmacother ; 67(4): 251-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23540285

RESUMO

In the tumor malignancy progression, lymph node metastasis (LNM) is recognized as an important factor. In this study, RNA interference (RNAi) was employed to down-regulate ANXA7 gene in Hca-F cells, a hepatocarcinoma cell line with high LNM rate. There was no significant effect on cell proliferation ability, but cell division, motility, and invasion abilities were markedly inhibited. By contrast, up-regulating the expression of ANXA7 gene in Hca-P cells with lower LNM rate, cell migration ability was improved and the percentage of cells in S phase was significantly decreased in vitro. Here, we reported that the expression of Ech1, GSN and JNK1 genes, which were relevant to tumor lymphatic metastasis, had been inhibited due to down-regulation ANXA7 gene and promoted due to up-regulation ANXA7 gene by western blot analysis. These results indicated that ANXA7 is a critical factor in the development of lymphatic metastasis in hepatocarcinoma progression.


Assuntos
Anexina A7/genética , Carcinoma Hepatocelular/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/patologia , Animais , Western Blotting , Isomerases de Ligação Dupla Carbono-Carbono/genética , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células , Regulação para Baixo , Gelsolina/genética , Neoplasias Hepáticas/genética , Metástase Linfática , Camundongos , Proteína Quinase 8 Ativada por Mitógeno/genética , Invasividade Neoplásica/genética , Interferência de RNA , Regulação para Cima
13.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 2): m188-9, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-22346859

RESUMO

The structure of the title compound, [Ni(NCS)(2)(C(6)H(8)N(2))(4)], consists of isolated mol-ecules of [Ni(NCS)(2)(Aim)(4)] (Aim = 1-allyl-imidazole), which contain a distorted octa-hedral NiN(6) chromophore. The NCS(-) anions are trans and four N atoms from the 1-allyl-imidazole ligands define the equatorial plane. The mean Mn-N(Aim) and Mn-N(NCS) distances are 2.105 (2) and 2.098 (2) Å, respectively. Weak C-H⋯N inter-actions contribute to the crystal packing stability.

14.
Artigo em Inglês | MEDLINE | ID: mdl-22259383

RESUMO

The structure of the title compound, [Mn(NCS)(2)(C(6)H(8)N(2))(4)], consists of isolated mol-ecules of [Mn(NCS)(2)(Aim)(4)] (Aim = 1-allyl-imidazole), which contain a compressed octa-hedral MnN(6) chromophore (site symmetry [Formula: see text]). The NCS(-) anions are trans and four N atoms from the Aim ligands define the equatorial plane. The mean Mn-N(Aim) and Mn-N(NCS) distances are 2.270 and 2.229 Å, respectively. Weak C-H⋯N inter-actions contribute to the crystal packing stability.

15.
Zhonghua Bing Li Xue Za Zhi ; 40(12): 830-3, 2011 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-22336209

RESUMO

OBJECTIVE: To study the expression of enoyl CoA hydratase 1 (ECH1) and the effect when down-regulation of ECH1 gene expression in mouse hepatocarcinoma cell. METHODS: Immunofluorescence was used for detecting the expression of ECH1, and stably transfected Hca-F cells with pGPU6/GFP/Neo-shRNA-ECH1 expression plasmids. Cell proliferation was assessed by Cell counting kit-8 (CCK8) assay. The Boyden-transwell assay (8 µm pore size) was performed to analyze the inhibitory effect of shRNA on Hca-F cell migration and invasion. RESULTS: ECH1 expression was obtained in the cytoplasm and upregulated expression in Hca-F cells than that in Hca-P cells. The down-regulation of ECH1 could inhibit the cell proliferation of Hca-F cells, decrease the number of cell pass through Transwell (27.07 ± 17.49) compared with scramble-negative (72.38 ± 18.83) and Hca-F controls (59.06 ± 30.33), decrease the migration capacities of Hca-F cells, increase the ratio of Hca-F cells in S phase (86.1%) compared with scramble-negative (75.8%) and Hca-F controls (66.2%) and decrease the ratio of G(1) phase (9.4%) compared with scramble-negative (24.2%) and Hca-F controls (30.3%). CONCLUSION: ECH1 serves as a potential critical factor attributes to tumor lymphatic metastasis.


Assuntos
Movimento Celular , Proliferação de Células , Enoil-CoA Hidratase/metabolismo , Neoplasias Hepáticas Experimentais/patologia , RNA Interferente Pequeno/genética , Animais , Ciclo Celular , Linhagem Celular Tumoral , Citoplasma/enzimologia , Regulação para Baixo , Enoil-CoA Hidratase/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas Experimentais/enzimologia , Metástase Linfática , Camundongos , Plasmídeos , Transfecção
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