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1.
Orthod Craniofac Res ; 2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-32202038

RESUMO

OBJECTIVE: To investigate the morphological characteristics of the mandible in subjects with impacted mandibular second molars by measuring and analyzing the mandible in three dimensions. SETTING AND SAMPLE POPULATION: In this retrospective study, the data of a total of 52,609 subjects who underwent cone-beam computed tomography (CBCT) for diagnosis and treatment were reviewed. According to the inclusion and exclusion criteria, 183 subjects with impacted mandibular second molars and 176 age- and sex-matched controls were included. METHODS: A retrospective case-control study was designed. The 183 subjects were divided into two groups: group 1 (G1) comprised 120 patients with unilaterally impacted mandibular second molars, and group 2 (G2) comprised 63 patients with bilaterally impacted mandibular second molars. Group 3 (G3) contained 176 age- and sex-matched controls. The mandible was reconstructed with nineteen landmarks using Mimics software. Twelve linear lengths and 3 angles were measured. RESULTS: The bilateral germination gap, mandibular body width and gonion width in G1 were significantly lower than those in G3 (P < 0.05), while the gnathion angle and first molar width values in G1 were significantly higher than those in G3 (P < 0.05). The results in G2 were similar to those in G1, but the differences between G2 and G3 were greater than those between G1 and G3. There were no significant differences in the other measurements among the groups. CONCLUSION: The mandibles of the subjects with impacted second molars were constricted in terms of the sagittal length and transverse width.

2.
Int J Biol Macromol ; 154: 173-181, 2020 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-32194099

RESUMO

A silane unit with enhanced synergism that is realized using one cationic quaternary ammonium salt (QAS) to draw anionic bacteria to two N-halamine functionalities was designed and polymerized on cellulose for superior biocidability. A monomer containing one tertiary amine, one amide N-H, and one imide N-H, was synthesized via alcoholysis of 3-triethoxysilylpropyl succinic anhydride with 2-(dimethylamino)ethan-1-ol and following esterification with 5-(4-hydroxyphenyl)hydantoin. The triethoxysilyl groups of the monomer were hydrolyzed to silanol groups to condense with counterparts in different hydrolyzates and with hydroxyl groups on cellulose to form a polymeric modifier. Each silane unit of the modifier has one QAS and two N-halamine functionalities (quat/di-N-halamines) after quaternization of the tertiary amine and chlorination of the amide and imide hydrogens. The resultant cellulose suppressed (7 logs) both Staphylococcus aureus and Escherichia coli within 3 min, demonstrating an enhanced synergism since the inactivation rate is faster than counterparts decorated with only N-halamine and with synergistic units of one cationic center and one N-halamine. The modifier exhibited promising stability and rechargeability toward washings, UV irradiation, and long-term storage. The proved enhanced synergism from the integration of one cationic center with multiple N-halamines directs the synthesis of more powerful biocides for developing antibacterial polymers.

3.
J Hazard Mater ; 386: 121977, 2020 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-31911381

RESUMO

Removal of hazardous NO at low temperature via photo-assisted selective catalytic reduction (photo-SCR) strategy is promising, however fully harvesting of solar energy and achieving high SO2/H2O tolerance still remain a challenge. Herein, the phosphoric acid modified natural attapulgite(P-ATP) was employed as a matrix to immobilize CeVO4 by microwave hydrothermal method. Results show that P-ATP provides abundant active sites facilitating the in situ grow of CeVO4 nanorods on its surface which hierarchically construct a dendritic-like photocatalyst. The near-infrared (NIR) light is upconverted to visible and UV light through CeVO4 which not only broaden the absorption range of solar light, but also build Z-scheme heterostructure with P-ATP enhancing the redox potential of charge carriers. The CeVO4/P-ATP nanocomposite can reach as high as 92 % for NO conversion under full-spectrum solar irradiation, while retaining nearly 60 % conversion under NIR light. Moreover, the catalyst exhibits outstanding tolerance with SO2 and H2O due to the presence of Ce species which can prevent NH3 from being sulfated, while ATP prevent catalyst from being corroded by H2O. This work may open up a new window for full-spectrum driven SCR of NO based on cost-effective mineral catalyst.

4.
Mol Genet Genomic Med ; 8(1): e1046, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31785132

RESUMO

BACKGROUND: Human leukocyte antigen (HLA)-DP is an HLA class II molecule. Overexpression of HLA class II molecules in placental trophoblast cells may induce pregnancy loss. However, the association between HLA-DP and pregnancy loss remains unclear. HLA-DPA1 is an HLA-DP peptide chain. The objective of this study was to assess the association between HLA-DPA1 genetic polymorphism and anembryonic pregnancy, a type of early pregnancy loss, in the Chinese population. METHODS: A case-control study was designed to compare the frequencies of HLA-DPA1 gene polymorphisms in an anembryonic pregnancy group and a control group. Sixty-eight cases and 122 controls were recruited. Statistical analysis was performed to assess the correlation between single-nucleotide polymorphisms (SNPs) and anembryonic pregnancy susceptibility. MassARRAY high-throughput DNA analysis was used to analyze 19 HLA-DPA1 SNPs. To explore how HLA-DPA1 polymorphism could affect anembryonic pregnancy, HLA-DPA1 serum levels were analyzed by ELISA. RESULTS: Homozygous typing of rs1431403 (CC and TT) significantly increased the risk of anembryonic pregnancy in the case group (ORCC  = 3.13, 95% CI: 1.50-6.53; ORTT  = 2.96, 95% CI: 1.31-6.66; ORCC+TT  = 3.06, 95% CI: 1.62-5.78). In samples with high HLA-DPA1 levels (≥1,500 pg/ml), the homozygous rs1431403 genotypes (nCC  = 21, 43.8%; nTT  = 20, 57.1%) were observed more frequently than were heterozygous genotypes. CONCLUSION: HLA-DPA1 rs1431403 may be a risk factor for anembryonic pregnancy in the Chinese population. Homozygous rs1431403 genotypes (CC and TT) may increase the risk of anembryonic pregnancy by aberrantly increasing the HLA-DPA1 levels.

5.
J Ethnopharmacol ; 246: 112221, 2020 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-31494203

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Donkey (Equus asinus) milk has become a medical and nutrient product since ancient times. In addition, donkey milk was regarded as a medicinal food and substitute product for infant formula in some ancient western countries. Chinese ancient medical books documented the medicinal value of donkey milk, using donkey milk to treat diabetes, cough and jaundice. AIM OF THE STUDY: To investigate the donkey milk's components and anti-diabetic effect of donkey milk in vitro and in vivo and to study the molecular mechanism of donkey milk was an anti-diabetic medication. MATERIALS AND METHODS: In this study, the gastrointestinal digested donkey milk was simulated in vitro and its products of protein digestion were analyzed by SDS-PAGE. We then performed cell viability assay, insulin secretion assay, animal experiments and ELISA assays to study the anti-diabetic effect of donkey milk in vitro and in vivo. Donkey milk's anti-diabetic molecular mechanism and specific targets were detected by using quantitative real time PCR. RESULTS: Lysozyme (LZ) and α-lactalbumin (α-La) exhibited significantly lower digestibility and higher retention than the other components of donkey milk. In vitro, 500 µg/mL of donkey milk could improve damaged ß-cells viability significantly (P < 0.0001). In vivo, the blood glucose and HOMA-IR of diabetic rats treated with donkey milk were 14.23 ±â€¯5.18 mM and 74.94 ±â€¯23.62, respectively, whereas the diabetic group were 22.18 ±â€¯2.23 mM and 112.16 ±â€¯18.44, respectively (P < 0.01). The SOD value of donkey milk group was 265.87 ±â€¯21.29 U/L, while the SOD value of diabetic group was 193.20 ±â€¯52.07 U/L (P < 0.05). These results indicated that the blood glucose was reduced, the ability of the body to eliminate free radicals was enhanced, antioxidant levels in the body was increased, insulin resistance was improved in type 2 diabetic rats after donkey milk powder fed for 4 weeks. Furthermore, donkey milk could treat diabetes through down-regulating phosphoenolpyruvate carboxykinase 1 (Pck1) and glucose-6-phosphatase (G6PC). CONCLUSIONS: Donkey milk has played an important role in the treatment of type 2 diabetes, and contributed to the development of the donkey milk products.


Assuntos
Equidae , Leite/metabolismo , Animais , Glicemia , Linhagem Celular , Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2/metabolismo , Insulina/metabolismo , Masculino , Camundongos , Leite/química , Ratos
6.
Nanoscale ; 11(46): 22440-22445, 2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31746893

RESUMO

High-throughput growth of large size transition metal dichalcogenide (TMD) single crystals is an important challenge for their applications in the next generation electronic and optoelectronic integration devices. Here we report the high-throughput growth of submillimeter monolayer TMD single crystals by two-stage space confined chemical vapor deposition, where the nucleation density of TMD crystals is significantly decreased for the growth of large size monolayer crystals by the space confinement effect. Moreover, high-throughput growth of submillimeter TMD crystals is also achieved by stacking the substrates along the perpendicular direction to the flow of the reaction gases. The mobilities of the TMD materials produced in this way are up to 1.2, 17.0 and 25.0 cm2 (V s)-1 for monolayer WS2, WSe2 and MoS2 single crystals, respectively. The results demonstrate that two-stage space confined growth is a highly promising method for high-throughput fabrication of high-quality submillimeter monolayer TMD single crystals, which will pave a new pathway to large-scale production of TMD-based electronic and optoelectronic devices.

7.
Front Psychol ; 10: 1443, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293484

RESUMO

An important theme in the development of self-psychology is the attempt by scholars to construct a self-model with universal cultural adaptability. Among them, representatives are the tripartite model of self-built by Triandis, the theory of the independent self and interdependent self-proposed by Markus and Kitayama, Yang Kuo-Shu's four-part theory of the Chinese self, Hwang Kwang-Kwo's Mandala model of self, and Shiah Yung-Jong's Non-self-Theory. However, these models have a difficult time explaining the structure and development of the Chinese self in Chinese cultural background. After pondering over Chinese traditional culture and the Chinese self, inspired by the archetype of Taiji diagram, in this paper, we construct the Taiji Model of Self. The Taiji Model of Self can not only properly represent the Chinese self-structure, but also explain the growth course of the Chinese self and four kinds of life realms of Chinese people with satisfactory cultural and ecological validity.

8.
Sensors (Basel) ; 19(12)2019 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-31234545

RESUMO

The Chang'e-4 (CE-4) lunar rover, equipped with a visible and near-IR imaging spectrometer (VNIS) based on acousto-optic tunable filter spectroscopy, was launched to the far side of the moon on December 8, 2018. The detection band of the VNIS ranges from 0.45 to 2.4 µm. Because of the weak reflection of infrared radiation from the lunar surface, a static electronic phase-locked acquisition method is adopted in the infrared channel for signal amplification. In this paper, full-link simulations and modeling are conducted on the infrared channel information flow of the instrument. The signal characteristics of the VNIS are analyzed in depth, and the signal to noise ratio (SNR) prediction and laboratory verification are presented. On 4 January 2019, the VNIS started working successfully and acquired high-resolution spectrum data of the far side of the moon for the first time. Through analysis we have found that the SNR ratio is in line with our predictions, and the data obtained by VNIS in orbit are consistent with the information model proposed in this paper.

9.
J Biomed Nanotechnol ; 15(8): 1781-1791, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31219021

RESUMO

The growth, migration and spread of malignant tumors requires a large number of new blood vessels to supply nutrients. In our previous study, it was found that the hyaluronic acid (HA) modified novel antiangiogenic peptide ES2-AF has better solubility, longer half-life, stronger targeting than non-modified ES2-AF, and it significantly inhibited the formation of new blood vessels. In the current work, we studied the stability of ES2-AF after HA modification, including heat stability, longterm stability, and pH stability. After treatment with HA-ES2-AF, cell apoptosis and the cell cycle were analyzed using flow cytometry. The inhibitory effect of HA-ES2-AF on tumors was investigated in vivo in HepG2 tumor-bearing nude mice. All the above results showed that HA-ES2-AF significantly improved stability, effectively induced apoptosis of endothelial cells, caused G1 phase arrest of endothelial cells, and decreased the percentage of cells in G2 and S phases. In vivo, HA-ES2-AF exhibited an inhibitory effect on tumors growth. In addition, the results provide a reliable basis for studying the inhibition of neovascularization and anti-tumor drugs in the future.


Assuntos
Nanopartículas , Neoplasias , Inibidores da Angiogênese , Animais , Ácido Hialurônico , Camundongos , Camundongos Nus
10.
Genes (Basel) ; 10(5)2019 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-31035529

RESUMO

In order to study the assembly mechanism of phycocyanin in red algae, the apo-phycocyanin genes (pcB and pcA) were cloned from Gracilariopsis lemaneiformis. The full length of phycocyanin ß-subunit (pcB) contained 519 nucleotides encoding a protein of 172 amino acids, and the full length of phycocyanin α-subunit(pcA) contained 489 nucleotides encoding a protein of 162 amino acids. Expression vector pACYCDuet-pcB-pcA was constructed and transformed into E. coli BL21 with pET-ho-pcyA (containing ho and pcyA gene to synthesize phycocyanobilin). The recombinant strain showed fluorescence activity, indicating the expression of optically active phycocyanin in E. coli. To further investigate the possible binding sites between phycocyanobilin and apo-phycocyanin, Cys-82 and Cys-153 of the ß subunit and the Cys-84 of the α subunit were respectively mutated, and four mutants were obtained. All mutant strains had lower fluorescence intensity than the non-mutant strains, which indicated that these mutation sites could be the active binding sites between apo-phycocyanin and phycocyanobilin (PCB). This research provides a supplement for the comprehensive understanding of the assembly mechanism of optically active phycocyanin in red algae.


Assuntos
Ficobilinas/genética , Ficocianina/genética , Rodófitas/genética , Sequência de Aminoácidos/genética , Sítios de Ligação/genética , Clonagem Molecular , Escherichia coli , Mutação/genética
11.
Int J Nanomedicine ; 14: 2573-2589, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31040673

RESUMO

Background: In the past few years, significant progress has been made in inhibiting neovascularization at the tumor site, cutting off the nutrient supply of the tumor, and inhibiting tumor growth and metastasis. However, many proteins/peptides have the disadvantage of poor stability, short half-life, and uncertain targeting ability. Chemical modification can be used to overcome these disadvantages; many polyethylene glycol-modified proteins/peptides have been approved by US FDA. The purpose of this study was to obtain a novel anti-angiogenic chondroitin sulfate (CS)-peptide nanoparticle conjugate with efficient anti-neovascularization and tumor targeting ability and an acceptable half-life. Materials and methods: The CS-ES2-AF nanoparticle conjugate was synthesized and characterized using 1H-nuclear magnetic resonance spectroscopy, transmission electron microscopy, and particle size and zeta potential analyzer. The anti-angiogenic ability was studied using MTT, migration, tube formation, and chick chorioallantoic membrane assays. The targeting ability of CS-ES2-AF was studied by ELISA, surface plasmon resonance, and bioimaging. The pharmacokinetics was also studied. Results: The CS-ES2-AF could self-assemble into stable nanoparticles in aqueous solution, which significantly enhances its anti-neovascularization activity, tumor targeting more explicit, and prolongs its half-life. Conclusion: CS is an effective protein/peptide modifier, and CS-ES2-AF displayed good potential in tumor targeting therapy.


Assuntos
Inibidores da Angiogênese/farmacologia , Sulfatos de Condroitina/farmacologia , Nanopartículas/química , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/uso terapêutico , Animais , Movimento Celular , Sulfatos de Condroitina/química , Sulfatos de Condroitina/farmacocinética , Sulfatos de Condroitina/uso terapêutico , Membrana Corioalantoide/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Nanopartículas/ultraestrutura , Neoplasias/irrigação sanguínea , Neoplasias/patologia , Neovascularização Patológica/tratamento farmacológico , Tamanho da Partícula , Peptídeos/uso terapêutico , Espectroscopia de Prótons por Ressonância Magnética , Fatores de Tempo , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Gene ; 697: 123-130, 2019 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-30794916

RESUMO

Haematococcus pluvialis is an economic microalga to produce astaxathin. To study the nitrogen metabolic process of H. pluvialis, the transcription level and enzyme content of nitrite reductase at different nitrate and phosphorus concentrations were studied. In this research, nitrite reductase gene (nir) was first cloned from H. pluvialis, which consists of 5592 nucleotides and includes 12 introns. The cDNA ORF is 1776 bp, encoding a 592 amino acid protein with two conserved domains. Phylogenetic analysis showed that the nir gene in H. pluvialis had the highest affinity with other freshwater green algae. Nitrogen and phosphorus play an important role in the growth of H. pluvialis. The single factor experiments of nitrogen on growth conditions showed that the group with 0.2 g/L NaNO3 had a relative high biomass. The single factor experiments of phosphorus on growth conditions showed that the group with 0.06 g/L K2HPO4 had a relative high biomass. The transcription level and enzymatic activity of nitrite reductase were detected at different nitrate and phosphorus concentrations. In the absence of nitrogen and phosphorus in the medium, nitrite reductase activity is the highest. This research provides theoretical guidance for optimization of culture medium for H. pluvialis and also provides an experimental basis for understanding of nitrogen metabolism pathway in H. pluvialis.


Assuntos
Clorofíceas/genética , Nitrito Redutases/genética , Clorófitas/genética , Nitritos/metabolismo , Nitrogênio/metabolismo , Fósforo/metabolismo , Filogenia
13.
Chem Commun (Camb) ; 55(19): 2753-2756, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30672935

RESUMO

ITQ-37 and ITQ-43 possessing mesoporous structures have aroused great interest because of their promising applications involving large molecules. However, it is challenging to synthesize these zeolites. Herein, MAS-ITQ-37 and MAS-ITQ-43 with enhanced Si/Ge ratios of 1.7 and 3.0 have been synthesized by using a simple matrine-derived organic structure-directing agent.

14.
Carbohydr Polym ; 208: 302-313, 2019 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-30658804

RESUMO

Most solid tumors require neovascularization during their growth. In our previous study, ES2 (IVRRADRAAVP) was covalently conjugated to soluble chitooligosaccharide chloride (HTCOSC) to form one novel HTCOSC-ES2 conjugate, which displayed better anti-angiogenic activity. In this work, the intracellular distribution and endocytosis of the conjugate in endothelial cells, as well effects on endothelial cell cycle and apoptosis were investigated. In addition, pharmacokinetic and antitumor studies were conducted. HTCOSC-ES2 entered the cell via clathrin and lipid valve pathway and was transported to the nucleus via lysosomal transport mechanism. Unlike ES2, HTCOSC-ES2 effectively inhibited the growth of endothelial cells and promoted apoptosis; thus, it could inhibit tumor angiogenesis, resulting in strong anti-tumor activity in vivo. The half-life of HTCOSC-ES2 was also prolonged, and its clearance was delayed. Immunohistochemistry assays showed that HTCOSC-ES2 obviously reduced the microvessel density, decreased the expression of VEGF, and increased the expression of caspase-3.


Assuntos
Antineoplásicos/farmacocinética , Antineoplásicos/uso terapêutico , Quitina/análogos & derivados , Peptídeos/química , Animais , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Quitina/química , Endocitose/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Feminino , Citometria de Fluxo , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL
15.
Carbohydr Polym ; 207: 79-90, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30600066

RESUMO

Endostatin (ES) has attracted considerable attention for the treatment of anti-angiogenesis-related disorders. An 11-amino-acid peptide (ES2, IVRRADRAAVP) from the amino terminal of ES is of interest because it is the main active fragment of ES. However, both ES and ES2 have a poor stability and a short half-life, and other disadvantages need to be further resolved. Thus, we conjugated ES2 to glycol-split heparin derivatives (GSHPs) to yield the polymer-peptide conjugate, GSHP-ES2. This study showed that GSHP-ES2 exhibited increased stability, a wider pH activity range, better inhibition of endothelial cell proliferation, migration and tube formation in vitro, better anti-angiogenic activity and a longer half-life in vivo compared with ES2. These results also indicate that GSHP-ES2 has good potential for the treatment of angiogenesis-related diseases, either alone or in combination with other chemicals.


Assuntos
Inibidores da Angiogênese/farmacologia , Endostatinas/farmacologia , Glicopeptídeos/farmacologia , Heparina/química , Oligopeptídeos/farmacologia , Inibidores da Angiogênese/síntese química , Inibidores da Angiogênese/farmacocinética , Inibidores da Angiogênese/toxicidade , Animais , Linhagem Celular , Movimento Celular/efeitos dos fármacos , Galinhas , Estabilidade de Medicamentos , Endostatinas/síntese química , Endostatinas/farmacocinética , Endostatinas/toxicidade , Feminino , Glicopeptídeos/síntese química , Glicopeptídeos/farmacocinética , Glicopeptídeos/toxicidade , Meia-Vida , Humanos , Camundongos Endogâmicos BALB C , Oligopeptídeos/síntese química , Oligopeptídeos/farmacocinética , Oligopeptídeos/toxicidade , Peixe-Zebra
16.
Hum Pathol ; 85: 194-201, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30500418

RESUMO

Histone deacetylase 1 (HDAC1) has been shown to be closely associated with tumor development. We investigated its effects on survival and biological behavior in gastric cancer (GC). HDAC1 expression and glycolysis activity were analyzed in a cohort of 252 samples of primary GC tumors and in vitro study. High HDAC1 (HDAC1High) staining was seen in 60.7% patients with GCs, which was significantly greater than was seen in normal epithelial cells (19.4%; P < .005). HDAC1High expression was associated with larger tumor size (P = .001), advanced T stage (P = .001), lymph node metastases (N stage; P < .001), and lymphovascular invasion (P = .005). Univariate and multivariate survival analyses showed HDAC1 expression to be an independent prognostic factor for both disease-free survival and overall survival (P < .05). In vitro studies showed a notably decreased glycolysis rate in HDAC1 knockdown cells. In patients' samples, HDAC1High expression was always accompanied with high Maximal standardized uptake value (SUVmax) value (P < .05). A hypoxia-inducible factor (HIF)-1α response element-luciferase reporter system showed HDAC1 to affect HIF1α activity in a dose-dependent manner. In conclusion, HDAC1 promotes glycolysis in GC and affects HIF-1α activity in tumor progression and metastasis. HDAC1High expression was also an independent adverse prognostic factor for overall survival and disease-free survival.


Assuntos
Glicólise/fisiologia , Histona Desacetilase 1/metabolismo , Metástase Linfática/patologia , Neoplasias Gástricas/metabolismo , Estômago/patologia , Linhagem Celular Tumoral , Progressão da Doença , Feminino , Mucosa Gástrica/metabolismo , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Neoplasias Gástricas/patologia , Taxa de Sobrevida
17.
Chemistry ; 25(9): 2184-2188, 2019 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-30521132

RESUMO

A new germanosilicate zeolite named SCM-15 (Sinopec Composite Material No. 15), the first zeolite containing a 3-dimensional (3D) channel system with interconnected 12-, 12-, and 10-ring channels (pore sizes: 6.1×7.2, 6.1×7.4, and 5.2×5.9 Å), has been synthesized using neutral 4-pyrrolidinopyridine as organic structure-directing agents (OSDAs). Its structure has been determined by combining single-crystal electron diffraction (SCED) and synchrotron powder X-ray diffraction (SPXD) data. The unique open framework structure of SCM-15 is related to that of FOS-5 (BEC), ITQ-7 (ISV), PKU-16 (POS), ITQ-26 (IWS), ITQ-21, Beta polymorph B, and SU-78B, since all these framework structures can be constructed from similar chains which are connected through shared 4-ring or double 4-ring (d4r) units. Based on this relation, six topologically reasonable 3D large or extra-large pore hypothetical zeolites are predicted.

18.
PLoS One ; 13(12): e0208853, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30533058

RESUMO

Aurantiochytrium limacinum has received attention because of its abundance of polyunsaturated fatty acids (PUFAs), particularly docosahexaenoic acid (DHA). DHA is synthesized through the polyketide synthase (PKS) pathway in A. limacinum. The related enzymes of the PKS pathway are mainly expressed by three gene clusters, called pks1, pks2 and pks3. In this study, the full-length pks3 gene was obtained by polymerase chain reaction amplification and Genome Walking technology. Based on a domain analysis of the deduced amino acid sequence of the pks3 gene, 3-ketoacyl-ACP reductase (KR) and dehydratase (DH) enzyme domains were identified. Herein, A. limacinum OUC168 was engineered by gene knock-in of KR and DH using the 18S rDNA sequence as the homologous recombination site. Total fatty acid contents and the degree of unsaturation of total fatty acids increased after the kr or dh gene was knocked in. The cloning and functional study of the pks3 gene of A. limacinum establishes a foundation for revealing the DHA synthetic pathway. Gene knock-in of the enzyme domain associated with PKS synthesis has the potential to provide effective recombinant strains with higher DHA content for industrial applications.


Assuntos
Hidroliases/genética , Oxirredutases/genética , Estramenópilas/genética , Clonagem Molecular , Ácidos Docosa-Hexaenoicos/metabolismo
19.
J Control Release ; 288: 1-13, 2018 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-30170067

RESUMO

Anti-flt1 peptide (GNQWFI, AF) specifically binds to Vascular Endothelial Growth Factor Receptor 1 (VEGFR1), thereby inhibiting the interaction of VEGFR1 with a series of ligands. ES2 (IVRRADRAAVP) can effectively inhibit the proliferation and invasion of endothelial cells and play a key role in anti-angiogenesis. AF and ES2 peptides differ in their activity. To better exploit the advantages of both, we designed a new peptide called ES2-AF (IVRRADRAAVPGGGGGGNQWFI). Hyaluronic acid (HA) is widely used in the pharmaceutical industry because of its biodegradable and high load performance. The HA-specific cell surface receptor CD44 was highly expressed in the tumour site during the anti-tumour study. Therefore, we used HA as a modifier to chemically modify ES2-AF; it was expected that the modified compound would have preferable solubility, stronger targeting, longer half-life, and better anti-angiogenesis effects in vivo. In this study, the anti-proliferative, anti-migration and targeting activities of HA-ES2-AF in vitro were studied by MTT, ELISA, transwell and SPR assays. Meanwhile, the anti-neovascularization activity of HA-ES2-AF in vivo was studied by CAM assay, and the targeting of HA-ES2-AF to tumour tissue was studied by bioimaging techniques. Finally, we also studied the half-life of HA-ES2-AF in vivo. In short, the bioactivity of the new peptide ES2-AF was enhanced to a certain extent, and ES2-AF modified by HA had higher anti-neovascularization activity in vitro and in vivo, had stronger targeting to tumour tissue, and had a significantly prolonged half-life in vivo. These results laid the foundation for its further development into targeting anti-tumour drugs.


Assuntos
Antineoplásicos/administração & dosagem , Endostatinas/administração & dosagem , Ácido Hialurônico/administração & dosagem , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Neovascularização Patológica/tratamento farmacológico , Fragmentos de Peptídeos/administração & dosagem , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Animais , Linhagem Celular , Embrião de Galinha , Membrana Corioalantoide/efeitos dos fármacos , Membrana Corioalantoide/fisiologia , Feminino , Camundongos Nus , Ratos Wistar
20.
Heliyon ; 4(9): e00778, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30211335

RESUMO

The purpose of this work was to study the sulfur concentration on bioleaching of heavy metals from pig manure employing indigenous sulfur-oxidizing bacteria. Also, the variations in physicochemical properties of pig manure before and after bioleaching were investigated. The results showed that sulfur concentration significantly affected the rate of acidification, sulfate production and metal solubilization during pig manure bioleaching process. A Michaelis-Menten type equation was utilized to interpret the relationships between sulfur concentration, sulfate production and metal solubilization in the bioleaching process. The rates of metal solubilization during pig manure bioleaching were well described by a first order kinetic equation related to time. After 12 days of bioleaching, 93%-97% of Zn, 96%-98% of Mn and 48%-94% of Cu were leached out from pig manure, respectively. The metals remaining in the pig manure residual were mainly existed in stable forms. In addition, elemental analysis showed that bioleaching process could significantly modify the dewaterbility and organic composition of pig manure. However, fertility analysis found that 9.0%-19.1% of nitrogen, 68.5%-71.0% of phosphorus, 76.5%-78.8% of potassium and 47.5%-49.4% of the total organic carbon (TOC) were lost from pig manure in the bioleaching process. Therefore, bioleaching process used in this study could be applied to remove heavy metals effectively from the pig manure, but more detailed studies need to be done to decrease the nutrients loss from pig manure.

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