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1.
Water Sci Technol ; 89(8): 2132-2148, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38678414

RESUMEN

Given the substantial environmental pollution from industrial expansion, environmental protection has become particularly important. Nowadays, anion exchange membranes (AEMs) are widely used in wastewater treatment. With the use of polyvinyl alcohol (PVA), ethylene-vinyl alcohol (EVOH) copolymer, and methyl iminodiacetic acid (MIDA), a series of cross-linked AEMs were successfully prepared using the solvent casting technique, and the network structure was formed in the membranes due to the cross-linking reaction between PVA/EVOH and MIDA. Fourier transform infrared spectrometer, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to analyze the prepared membranes. At the same time, its comprehensive properties which include water uptake, linear expansion rate, ion exchange capacity, thermal stability, chemical stability, and mechanical stability were thoroughly researched. In addition, diffusion dialysis performance in practical applications was also studied in detail. The acid dialysis coefficient (UH+) ranged from 10.2 to 35.6 × 10-3 m/h. Separation factor (S) value ranged from 25 to 38, which were all larger than that of the commercial membrane DF-120 (UH+: 8.5 × 10-3 m/h, S: 18.5). The prepared membranes had potential application value in acid recovery.


Asunto(s)
Membranas Artificiales , Alcohol Polivinílico , Alcohol Polivinílico/química , Iminoácidos/química , Difusión , Purificación del Agua/métodos , Diálisis/métodos , Intercambio Iónico , Aniones/química , Polivinilos/química
2.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 51(5): 685-690, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-32975085

RESUMEN

OBJECTIVE: To analyze the epidemiological characteristics of hand, foot and mouth disease (HFMD) in Sichuan Province from 2013 to 2019. To study the correlation between meteorological factors and the incidence of HFMD and construct a prediction model. METHODS: The HMFD surveillance data and meteorological data from 2013 to 2019 in Sichuan Province were collected through the Chinese Center for Disease Control and Prevention and the China Meteorological data Network. Spearman correlation was used to analyze the relationship between HFMD incidence and meteorological factors. Multiple regression model and support vector regression (SVR) model were used to construct HFMD incidence prediction models respectively. RESULTS: A total of 615 840 cases of HFMD and 81 deaths were reported from 2013 to 2019. The average annual incidence rate was 107.31/105, and the mortality rate was 0.16/106. Spearman correlation analysis showed that the monthly incidence rate of HFMD was correlated with monthly average relative humidity (r=0.342), monthly average temperature (r=0.284), monthly average water vapor pressure (r=0.304) and monthly average days of precipitation (r=0.259). The prediction effect of the SVR model (R2=0.836) was better than the multiple regression model (R2=0.375). The SVR model provided a good fit to the monthly incidence of HFMD from 2013 to 2018, and can predict the peak incidence of HFMD in 2019. CONCLUSION: Relative humidity has the greatest influence on the incidence of HFMD. The fitting value of SVR model is in good agreement with the actual value, which is valuable in predicting the incidence of HFMD in Sichuan Province.


Asunto(s)
Enfermedad de Boca, Mano y Pie , China/epidemiología , Enfermedad de Boca, Mano y Pie/epidemiología , Humanos , Incidencia , Conceptos Meteorológicos , Temperatura
4.
Bioprocess Biosyst Eng ; 40(3): 361-372, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27796571

RESUMEN

Integrated approaches using in silico model-based design and advanced genetic tools have enabled efficient production of fuels, chemicals and functional ingredients using microbial cell factories. In this study, using a recently developed genome-scale metabolic model for Escherichia coli iJO1366, a mutant strain has been designed in silico for the anaerobic growth-coupled production of a simple polyol, glycerol. Computational complexity was significantly reduced by systematically reducing the target reactions used for knockout simulations. One promising penta knockout E. coli mutant (E. coli ΔadhE ΔldhA ΔfrdC ΔtpiA ΔmgsA) was selected from simulation study and was constructed experimentally by sequentially deleting five genes. The penta mutant E. coli bearing the Saccharomyces cerevisiae glycerol production pathway was able to grow anaerobically and produce glycerol as the major metabolite with up to 90% of theoretical yield along with stoichiometric quantities of acetate and formate. Using the penta mutant E. coli strain we have demonstrated that the ATP formation from the acetate pathway was essential for growth under anaerobic conditions. The general workflow developed can be easily applied to anaerobic production of other platform chemicals using E. coli as the cell factory.


Asunto(s)
Escherichia coli/genética , Escherichia coli/fisiología , Glicerol/química , Polímeros/química , Saccharomyces cerevisiae/genética , Acetatos/química , Anaerobiosis , Simulación por Computador , ADN/química , Escherichia coli/metabolismo , Fermentación , Formiatos/química , Genoma Bacteriano , Genoma Fúngico , Microbiología Industrial , Ingeniería Metabólica/métodos , Plásmidos/metabolismo , Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiología
5.
Blood Cells Mol Dis ; 59: 16-24, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27282562

RESUMEN

BACKGROUND: The multidrug resistance of leukemia cells is closely related to the microenvironment. The present leukemia microenvironment models focus on two-dimensional co-culture system in vitro which does not mimic the in vivo cell growth, while the 3D polystyrene (PS) scaffolds have the advantage. Stromal cell derived factor-1 may be involved in the shielding of endosteal niche from leukemia cells by binding to its receptor CXCR4, but the relationship between SDF-1/CXCR4 axis and leukemia cells is unclear. DESIGN AND METHODS: The experiments were built on the 3D PS scaffolds coated with osteoblasts. Stromal cells and MV4-11 cells were plated on the scaffolds. Then G-CSF, AMD3100 and cytarabine were added. Adhesive rate, SDF-1 level, migration state, apoptosis rate, and cell cycle of leukemia cells were observed after incubation at 24h and 48h. RESULTS: G-CSF decreased the level of SDF-1 and inhibited the expression of CXCR4 and promoted stationary phase leukemia cells to enter the mitotic phase and enhanced the killing effect of chemotherapeutic drugs. AMD3100 disrupted the interaction between tumors and matrix, mobilized the leukemia cells to keep away from the protective microenvironment and strengthened the cytotoxic effect of Ara-C. The combination of G-CSF and AMD3100 had stronger effects on killing the leukemia cells induced by Ara-C. CONCLUSION: It demonstrates that AMD3100 and G-CSF may inhibit adhesion and migration abilities of leukemia cells with the bone marrow niche. Both of them inhibit the role of SDF-1/CXCR4 directly or indirectly. Thus inhibiting SDF-1/CXCR4 axis may be helpful to the treatment of refractory AML.


Asunto(s)
Materiales Biomiméticos , Factor Estimulante de Colonias de Granulocitos/farmacología , Compuestos Heterocíclicos/farmacología , Leucemia/patología , Receptor Cross-Talk/efectos de los fármacos , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Bencilaminas , Adhesión Celular , Movimiento Celular , Células Cultivadas , Quimiocina CXCL12/metabolismo , Ciclamas , Citarabina/farmacología , Humanos , Leucemia Mieloide Aguda/patología , Poliestirenos , Receptores CXCR4/metabolismo , Células del Estroma/citología
6.
Biol Pharm Bull ; 37(5): 785-93, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24599033

RESUMEN

A set of polyethylene glycol (PEG)-resveratrol (RES) conjugates with amino acid as spacers was designed and synthesized to improve certain defects of resveratrol, such as poor solubility, its short half-life and the difficulty of obtaining controlled release. Amino acids, which are released along with RES, are necessary for human health and likely have a facilitating effect on the absorption of the drug. The prepared PEG conjugates were characterized by FT-IR, (1)H-NMR, X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Evaluation of free RES, loading capability, solubility and in vitro release of conjugates was also conducted. The results show that solubility in water of all the conjugates is over 900 mg·mL(-1) and controlled release of RES was achieved. Therefore, the developed PEG conjugate is a favorable system for modifying the solubility and bioavailability of RES.


Asunto(s)
Aminoácidos/química , Liberación de Fármacos , Polietilenglicoles/química , Estilbenos/química , Disponibilidad Biológica , Diseño de Fármacos , Profármacos/síntesis química , Profármacos/química , Profármacos/farmacocinética , Resveratrol , Solubilidad , Estilbenos/metabolismo
7.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(9): 2460-5, 2014 Sep.
Artículo en Zh | MEDLINE | ID: mdl-25532345

RESUMEN

A novel ultraviolet absorption spectrometry method was developed for the quantitative determination of HABS by adding ß-cyclodextrin with the molar ratio of 1:1 in strong interference aqueous solution. The results indicated that the effect of several common interfering flooding agents (SAS, OP-10, HPAM) on the determination of HABS could be greatly reduced in ß- cyclodextrin aqueous solution. Thus, the determination errors of the determined HABS were less than 2.0% under strong inter- ference, and the detection limit (S/N==3) of the method could be also as high was 8.3-9.1 x 10(-4) mg · L(-1). Various characterization results including 1H-NMR, TG-DSC and FTIR showed the interaction between ß-cyclodextrin and HABS. The results of H-NMR analysis showed that HABS molecule could enter into the interior of the cavity of ß-cyclodextrin molecule. TG-DSC analysis exhibited that the stable inclusion of ß-cyclodextrin and HABS could be automatically formed. The interactions between the functional groups of ß-cyclodextrin and HABS were showed by FTIR analysis, which also exhibited that the stable inclusion could be formed by HABS entering from the narrow or the broad mouth of the ß-cyclodextrin. The interference of the UV spectrum of HABS could be reduced by ß-cyclodextrin since the interaction between ß-cyclodextrin due to the interaction between ß-cyclodextrin and HABS in the inclusion complex.


Asunto(s)
beta-Ciclodextrinas/química , Espectrofotometría Ultravioleta
8.
Regen Ther ; 25: 308-319, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38327718

RESUMEN

Natural macromolecules like alginate and gelatin are employed to create medication delivery systems that are both safe and effective. Zirconium nanoparticles (ZrO2 NPs) have been proposed as a means of enhancing the alginate-gelatin hydrogel's physical and biological properties. This study combines the synthesis of the biopolymers gelatin and alginate nanofibers with nanoparticles of zirconium oxide (GA/NF- ZrO2 NPs). UV, XRD, FTIR, and SEM were used to characterize the synthesized nanofibers. The expression of osteogenic genes was analyzed by western blotting and qualitative real-time polymerase chain reaction (qRT-PCR). Based on our findings, MC3T3-E1 cells are performed for cell viability, apoptosis and reactive oxygen species production by GA/NF- ZrO2 NPs through the Wnt/ß-catenin signaling pathway. Cell migration was accelerated at 75 µg/mL concentration after 24 h of damage in a scratch wound healing assay. Proliferation of the MC3T3-E1 cell line was also detected. GA/NF-ZrO2 NPs influenced the osteogenic variation of MC3T3-E1 cells by inducing autophagy. Furthermore, the impact of obstruction on the temporomandibular joint (TMJ) is a subject of ongoing discussion and analysis within the context of animal models. Coordinated GA/NF-ZrO2 NPs on biomaterial nanofibers could be used to introduce physical signals for modifying MC3T3-E1 responds for orthodontic engineering constructs.

9.
Vaccine ; 41(28): 4183-4189, 2023 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-37244808

RESUMEN

BACKGROUND: The mechanism for anaphylaxis following mRNA COVID-19 vaccination has been widely debated; understanding this serious adverse event is important for future vaccines of similar design. A mechanism proposed is type I hypersensitivity (i.e., IgE-mediated mast cell degranulation) to polyethylene glycol (PEG). Using an assay that, uniquely, had been previously assessed in patients with anaphylaxis to PEG, our objective was to compare anti-PEG IgE in serum from mRNA COVID-19 vaccine anaphylaxis case-patients and persons vaccinated without allergic reactions. Secondarily, we compared anti-PEG IgG and IgM to assess alternative mechanisms. METHODS: Selected anaphylaxis case-patients reported to U.S. Vaccine Adverse Event Reporting System December 14, 2020-March 25, 2021 were invited to provide a serum sample. mRNA COVID-19 vaccine study participants with residual serum and no allergic reaction post-vaccination ("controls") were frequency matched to cases 3:1 on vaccine and dose number, sex and 10-year age category. Anti-PEG IgE was measured using a dual cytometric bead assay (DCBA). Anti-PEG IgG and IgM were measured using two different assays: DCBA and a PEGylated-polystyrene bead assay. Laboratorians were blinded to case/control status. RESULTS: All 20 case-patients were women; 17 had anaphylaxis after dose 1, 3 after dose 2. Thirteen (65 %) were hospitalized and 7 (35 %) were intubated. Time from vaccination to serum collection was longer for case-patients vs controls (post-dose 1: median 105 vs 21 days). Among Moderna recipients, anti-PEG IgE was detected in 1 of 10 (10 %) case-patients vs 8 of 30 (27 %) controls (p = 0.40); among Pfizer-BioNTech recipients, it was detected in 0 of 10 case-patients (0 %) vs 1 of 30 (3 %) controls (p >n 0.99). Anti-PEG IgE quantitative signals followed this same pattern. Neither anti-PEG IgG nor IgM was associated with case status with both assay formats. CONCLUSION: Our results support that anti-PEG IgE is not a predominant mechanism for anaphylaxis post-mRNA COVID-19 vaccination.


Asunto(s)
Anafilaxia , Vacunas contra la COVID-19 , COVID-19 , Femenino , Humanos , Masculino , Anafilaxia/etiología , COVID-19/prevención & control , Vacunas contra la COVID-19/efectos adversos , Inmunoglobulina E , Inmunoglobulina G , Inmunoglobulina M , Inmunosupresores , Polietilenglicoles/efectos adversos , ARN Mensajero , Vacunación/efectos adversos
10.
Shanghai Kou Qiang Yi Xue ; 31(4): 439-444, 2022 Aug.
Artículo en Zh | MEDLINE | ID: mdl-36710562

RESUMEN

PURPOSE: To guide clinical decision-making more efficiently via collecting and analyzing the imaging data of patients with Stafne bone cavity(SBC). METHODS: Six patients with SBC were retrospectively reviewed in Stomatological Hospital of Shandong University. By assessing cone-beam CT (CBCT) data, age, sex, complaint, cavity location, diameter at three dimension, maximal cross-sectional area of multi-planar reconstruction planes, content gray scale, morphological classification and its relationship with mandibular canal were recorded respectively. RESULTS: A total of 6 cases were inadvertently found on CBCT, with no symptoms. The locations of SBC were between mandibular molar region and mandibular angle, inferior border of mandible and mandibular canal, mostly at lingual side. Three were on the left and three were on the right. The bone cavity was elliptic and its long axis was consistent with the long axis of the mandible, with an average long axis diameter of (16.43±4.54) mm, horizontal axis diameter of (6.91±1.48) mm, vertical axis diameter of (10.24±2.10) mm. According to the multi-planar reconstruction planes readings, the maximal cross-sectional area of the bone cavity was (91.93±25.52) mm2, the maximal coronal area was (57.26±23.23) mm2, and the maximal sagittal area was (127.80±51.22) mm2. In view of the classification in the relationship between SBC marginal line and buccal cortical bone, there were 2 cases of type I cavity, 3 cases of type II cavity and 1 case of type III cavity. The connection between the bone cavity and the surrounding anatomical structure was classified into 3 conditions: covering penetration, adjacency and separation on the basis of the relative position between the cavity boundary with the mandibular inferior margin and the mandibular canal in sagittal plane. In addition, the content type could be primarily identified depending on estimation of corrected grey scale in the center of bone cavity. CONCLUSIONS: CBCT can make an intuitive and clear diagnosis of Stafne bone cavity, which brings great significance into the early clinical decision-making, thus not only avoiding unnecessary surgery, reducing the waste of additional medical resources, but also decreasing the physical and mental trauma of patients.


Asunto(s)
Diente Molar , Lengua , Humanos , Estudios Retrospectivos , Mandíbula/diagnóstico por imagen , Mandíbula/anatomía & histología , Tomografía Computarizada de Haz Cónico/métodos
11.
Viruses ; 14(12)2022 11 30.
Artículo en Inglés | MEDLINE | ID: mdl-36560696

RESUMEN

Coxsackievirus B5 (CVB5) is an important enterovirus B species (EV-Bs) type. We used the full-length genomic sequences of 53 viral sequences from the national hand, foot, and mouth disease surveillance network in the Chinese mainland (2001-2021). Among them, 69 entire VP1 coding region nucleotide sequences were used for CVB5 genotyping and genetic evolution analysis. Phylogenetic analysis based on a data set of 448 complete VP1 sequences showed that CVB5 could be divided into four genotypes (A-D) worldwide. Sequences from this study belonged to genotypes B and D, which dominated transmission in the Chinese mainland. Two transmission lineages of CVB5 have been discovered in the Chinese mainland, lineage 2 was predominant. Markov chain Monte Carlo analysis indicated that the tMRCA of CVB5 in the Chinese mainland could be traced to 1955, while the global trend could be traced to 1862, 93 years earlier than China. The evolution rate of CVB5 was higher in the Chinese mainland than worldwide. The spatiotemporal dynamics analysis of CVB5 assessed that virus transportation events were relatively active in Central, Northeast, North and Northwest China. Recombination analysis revealed frequent intertypic recombination in the non-structural region of CVB5 genotypes B and D with the other EV-Bs, revealing eight recombination lineages. Our study showed the molecular evolution and phylogeography of CVB5 that could provide valuable information for disease prevention.


Asunto(s)
Enterovirus Humano B , Enfermedad de Boca, Mano y Pie , Humanos , Filogenia , Epidemiología Molecular , Enterovirus Humano B/genética , Genotipo , China/epidemiología , Enfermedad de Boca, Mano y Pie/epidemiología
12.
Medicine (Baltimore) ; 101(33): e29249, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35984133

RESUMEN

The aim of the present study was to observe the abrasion of implant drills and postoperative reactions for the preparation of the interradicular immediate implant bed during the COVID-19 pandemic and beyond. Thirty-two implant drills were included in four groups: blank, improved surgery, traditional surgery, and control. In the improved surgery group, a dental handpiece with a surgical bur was used to decoronate the first molar and create a hole in the middle of the retained root complex, followed by the pilot drilling protocol through the hole. The remaining root complex was separated using a surgical bur and then extracted. Subsequently, the implant bed was prepared. Implant drills were used in the traditional surgery group to complete the decoronation, hole creation, and implant-drilling processes. The tooth remained intact until the implant bed was prepared. The surface roughness of the pilot drill was observed and measured. Surgery time, postoperative reactions (swelling, pain, and trismus), and fear of coronavirus disease 2019 scale (FCV-19S) were measured and recorded, respectively. Statistical analysis revealed significant difference with surface roughness among blank group (0.41 ± 0.05 µm), improved surgery group (0.37 ± 0.06 µm), traditional surgery group (0.16 ± 0.06 µm), and control group (0.26 ± 0.04 µm) (P < .001). Significant differences were revealed with surgery time between improved surgery group (5.63 ± 1.77 min) and traditional surgery group (33.63 ± 2.13 min) (P < .001). Swelling, pain, and trismus (improved group: r ≥ 0.864, P ≤ .006; traditional group: r ≥ 0.741, P ≤ .035) were positively correlated with the FCV-19S. This study proved that a new pilot drill could only be used once in traditional surgery but could be used regularly in improved surgery. Improved surgery was more effective, efficient, and economical than the traditional surgery. The higher FCV-19S, the more severe swelling, pain, and trismus.


Asunto(s)
COVID-19 , COVID-19/epidemiología , Implantación Dental Endoósea , Humanos , Diente Molar/cirugía , Dolor/cirugía , Pandemias/prevención & control , Trismo
13.
Opt Express ; 19(13): 12496-502, 2011 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-21716489

RESUMEN

By depositing a nanoscale photoconductive layer on a stable photorefractive (PR) polymeric film, consisting of the polymer poly[N-vinylcarbazole] (PVK) doped with 4,4'-n-pentylcyanobiphenyl (5CB) and C60, both the response rate and beam coupling properties were improved greatly. Systematic measurements and observations unveiled the role played by the additive layer in preventing ion injection from the ITO layer into the PR film and hence in mitigating the charge compensation. A strong fanning effect and high diffraction orders at small angles have demonstrated the excellent PR property in the modified samples used. To demonstrate great potential of the PR composite in the updatable applications, real time double exposure interferometry was performed accordingly with good results.


Asunto(s)
Compuestos de Bifenilo/química , Fulerenos/química , Holografía/instrumentación , Cristales Líquidos/química , Nanotecnología/instrumentación , Nitrilos/química , Polivinilos/química , Holografía/métodos , Interferometría/instrumentación , Interferometría/métodos , Modelos Teóricos , Nanotecnología/métodos , Refractometría/instrumentación , Refractometría/métodos , Temperatura
14.
Drug Chem Toxicol ; 34(2): 208-12, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21314471

RESUMEN

Polyethylene glycol 400 (PEG-400) has been used in injections. However, limited data are available concerning the toxicity of a high dose of PEG-400 following intravenous (i.v.) injection. The aim of the present study was to estimate the systemic toxicity and toxicokinetics of a high dose of PEG-400 in dogs following i.v. injection. Twenty-four dogs were divided into four groups: a control group receiving normal saline and three test groups receiving 4.23, 6.34, and 8.45 g/kg of PEG-400, respectively, by i.v. injection once a day for 30 days. The repeated-dose toxicity of PEG-400 was assessed. Toxicokinetic parameters of PEG-400 in dogs were estimated on days 1 and 30. Dry mouth and dry nasal mucus membrane were observed in dogs treated with 6.34 and 8.45 g/kg of PEG-400. Cloudy swelling of kidney cell and increased glomerular volume were observed in dogs treated with 8.45 g/kg of PEG-400 when the animals were sacrificed 24 hours after the last injection. No significant histological changes were found 21 days later. Repeated dosing did not affect the toxicokinetic profile of PEG-400 in dogs. This study has shown that the toxicity of a high dose of PEG-400 following repeated intravenous injections is low, and alterations produced are reversible.


Asunto(s)
Portadores de Fármacos/farmacocinética , Portadores de Fármacos/toxicidad , Polietilenglicoles/farmacocinética , Polietilenglicoles/toxicidad , Animales , Área Bajo la Curva , Pruebas de Química Clínica , Perros , Femenino , Pruebas Hematológicas , Inyecciones Intravenosas , Riñón/efectos de los fármacos , Riñón/metabolismo , Riñón/patología , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/patología , Masculino , Pruebas de Toxicidad
15.
J Mater Chem B ; 9(3): 536-566, 2021 01 28.
Artículo en Inglés | MEDLINE | ID: mdl-33289777

RESUMEN

Biomolecules have been thoroughly investigated in a multitude of solvents historically in order to accentuate or modulate their superlative properties in an array of applications. Ionic liquids have been extensively explored over the last two decades as potential replacements for traditional organic solvents, however, they are sometimes associated with a number of limitations primarily related to cost, convenience, accessibility, and/or sustainability. One potential solvent which is gaining considerable traction in recent years is the so-called deep eutectic solvent which holds a number of striking advantages, including biodegradability, inherently low toxicity, and a facile, low-cost, and solventless preparation from widely available natural feedstocks. In this review, we highlight recent progress and insights into biomolecular behavior within deep eutectic solvent-containing systems, including discussions of their demonstrated utility and prospects for the biostabilization of proteins and nucleic acids, free enzyme and whole-cell biocatalysis, various extraction processes (e.g., aqueous biphasic systems, nanosupported separations), drug solubilization, lignocellulose biomass treatment, and targeted therapeutic drug delivery. All indications point to the likelihood that these emerging solvents have the capacity to satisfy the requirements of environmental responsibility while unlocking biomolecular proficiency in established biomedical and biotechnological pursuits as well as a number of academic and industrial ventures not yet explored.


Asunto(s)
Materiales Biocompatibles/química , Líquidos Iónicos/química , Tamaño de la Partícula , Solventes/química , Propiedades de Superficie
16.
Environ Int ; 140: 105750, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32361124

RESUMEN

Coexposure of MPs and other contaminants adsorbed from the environment has raised many attentions, but the understanding of the combined effects of MPs and plastic additives are limited. Butylated hydroxyanisole (BHA), a widely used synthetic phenolic antioxidant in plastics, has gained high concerns due to their unintended environmental release and potential threat to aquatic organisms. This study was conducted to reveal the influences of MPs on the bioaccumulation and developmental toxicity of BHA in zebrafish larvae. As a result, MPs promoted the accumulation of BHA in zebrafish larvae and enhanced the toxicity of BHA in larvae development manifested by reduced hatching rates, increased malformation rates and decreased calcified vertebrae. Although the concentration of MPs was not sufficient to cause obvious developmental toxicity, the impacts of MPs on thyroid hormones status might contribute to the aggravated join toxicity. The metabolomic mechanism was revealed to be that the coexposure of BHA and MPs affected the development of zebrafish larvae via disturbing the metabolism of arachidonic acid, glycerophospholipid, and lipids. Our results emphasized that MPs, even at the nontoxic concentrations, in combination with additives caused health risk that should not be ignored.


Asunto(s)
Contaminantes Químicos del Agua , Pez Cebra , Animales , Antioxidantes , Microplásticos , Plásticos , Glándula Tiroides , Contaminantes Químicos del Agua/toxicidad
17.
J Biotechnol ; 139(1): 47-54, 2009 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-18822323

RESUMEN

The efficient conversion of lignocellulosic materials into fuel ethanol has become a research priority in producing affordable and renewable energy. The pretreatment of lignocelluloses is known to be key to the fast enzymatic hydrolysis of cellulose. Recently, certain ionic liquids (ILs) were found capable of dissolving more than 10wt% cellulose. Preliminary investigations [Dadi, A.P., Varanasi, S., Schall, C.A., 2006. Enhancement of cellulose saccharification kinetics using an ionic liquid pretreatment step. Biotechnol. Bioeng. 95, 904-910; Liu, L., Chen, H., 2006. Enzymatic hydrolysis of cellulose materials treated with ionic liquid [BMIM]Cl. Chin. Sci. Bull. 51, 2432-2436; Dadi, A.P., Schall, C.A., Varanasi, S., 2007. Mitigation of cellulose recalcitrance to enzymatic hydrolysis by ionic liquid pretreatment. Appl. Biochem. Biotechnol. 137-140, 407-421] suggest that celluloses regenerated from IL solutions are subject to faster saccharification than untreated substrates. These encouraging results offer the possibility of using ILs as alternative and non-volatile solvents for cellulose pretreatment. However, these studies are limited to two chloride-based ILs: (a) 1-butyl-3-methylimidazolium chloride ([BMIM]Cl), which is a corrosive, toxic and extremely hygroscopic solid (m.p. approximately 70 degrees C), and (b) 1-allyl-3-methylimidazolium chloride ([AMIM]Cl), which is viscous and has a reactive side-chain. Therefore, more in-depth research involving other ILs is much needed to explore this promising pretreatment route. For this reason, we studied a number of chloride- and acetate-based ILs for cellulose regeneration, including several ILs newly developed in our laboratory. This will enable us to select inexpensive, efficient and environmentally benign solvents for processing cellulosic biomass. Our data confirm that all regenerated celluloses are less crystalline (58-75% lower) and more accessible to cellulase (>2 times) than untreated substrates. As a result, regenerated Avicel((R)) cellulose, filter paper and cotton were hydrolyzed 2-10 times faster than the respective untreated celluloses. A complete hydrolysis of Avicel((R)) cellulose could be achieved in 6h given the Trichoderma reesei cellulase/substrate ratio (w/w) of 3:20 at 50 degrees C. In addition, we observed that cellulase is more thermally stable (up to 60 degrees C) in the presence of regenerated cellulose. Furthermore, our systematic studies suggest that the presence of various ILs during the hydrolysis induced different degrees of cellulase inactivation. Therefore, a thorough removal of IL residues after cellulose regeneration is highly recommended, and a systematic investigation on this subject is much needed.


Asunto(s)
Celulasa/metabolismo , Celulosa/metabolismo , Líquidos Iónicos/química , Adsorción , Cristalización , Cinética , Estabilidad Proteica , Espectroscopía Infrarroja por Transformada de Fourier , Temperatura , Trichoderma/enzimología
18.
Methods Enzymol ; 627: 1-21, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31630737

RESUMEN

Aliphatic polyesters are thermoplastic and biodegradable polymers with promising potentials to substitute synthetic polymers derived from petrochemicals. In particular, polylactides (PLAs) and other polylactones can be renewable and biocompatible. A more benign approach for polyester synthesis is the enzymatic polycondensation or ring-opening polymerization (ROP) reactions, whose outcomes largely depend on the reaction conditions including solvents, water content and temperature. This chapter illustrates several examples of enzymatic polymerization to polyesters using various solvents (i.e., organic solvents, supercritical fluids, ionic liquids, and aqueous biphasic systems). Hydrophobic solvents containing little water tend to promote the enzymatic polymerization and lead to high molecular masses of polyesters. Since some enzymatic polymerization reactions are performed at high temperatures (such as ring-opening polymerization of lactide at >100°C), these processes demand solvents with high boiling points (such as many ionic liquids). Supercritical fluids (such as supercritical CO2) can be "green" solvents, but their compatibility with enzymes and their practicability of scaling up remain as challenges. On the other hand, ionic liquids can be tailored to be compatible with enzymes and to have high thermal stability although the studies of their uses in enzymatic polycondensation and ROP reactions are still at an early stage.


Asunto(s)
Enzimas/metabolismo , Poliésteres/metabolismo , Polimerizacion , Solventes , Biocatálisis , Poliésteres/síntesis química
19.
PLoS One ; 14(12): e0225247, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31825954

RESUMEN

BACKGROUND: Epidemiological studies have shown that gastrointestinal Helicobacter pylori (H. pylori) infection is the main cause of chronic gastritis, but the relation between oral H. pylori and chronic periodontitis (CP) remains uncertain. A meta-analysis of published papers was performed to elucidate the correlation between oral H. pylori and CP. METHOD: To perform this meta-analysis, we searched papers published from 2000 to 2018 on PubMed, OVID, Springer Link, Chinese National Knowledge Infrastructure (CNKI) and Chinese Biology Medicine search engines. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) for the correlation between H. pylori and CP were estimated. Heterogeneity, publication bias and subgroup analyses were also conducted. RESULTS: A total of 918 papers on oral H. pylori and CP were collected, and 11 papers were in accordance with the inclusion criteria. Oral H. pylori was suggested to be correlated with CP. The results indicated that a H. pylori-positive state significantly increased the risk of CP 3.42 times (OR = 3.42; 95% CI = 2.71-4.31). A diagnostic test using polymerase chain reaction (PCR) showed a higher prevalence of H. pylori (OR = 3.70; 95% CI = 2.66-5.14) than did that using the rapid urease test (RUT) (OR = 3.13; 95% CI = 2.26-4.34). CONCLUSIONS: This paper demonstrated that CP was potentially correlated with oral H. pylori in adults and that oral H. pylori may be a possible risk factor for CP.


Asunto(s)
Periodontitis Crónica/epidemiología , Infecciones por Helicobacter/epidemiología , Helicobacter pylori , Comorbilidad , Humanos , Factores de Riesgo
20.
Artículo en Inglés | MEDLINE | ID: mdl-32039051

RESUMEN

Oral microbial dysbiosis is known to increase susceptibility of an individual to develop rheumatoid arthritis (RA). Individuals at-risk of RA may undergo different phases of disease progression. In this study, we aim to investigate whether and whereby the oral microbiome communities alter prior to symptoms of RA. Seventy-nine saliva samples were collected from 29 high-risk individuals, who were positive for anti-citrullinated protein antibodies (ACPA) and have no clinical arthritis, 27 RA patients and 23 healthy controls (HCs). The salivary microbiome was examined using 16S ribosomal RNA gene sequencing. Alpha and beta diversity analysis and the linear discriminant analysis were applied to examine the bacterial diversity, community structure and discriminatory taxa between three groups, respectively. The correlation between salivary bacteria and autoantibodies were analyzed. In the "pre-clinical" stages, salivary microbial diversity was significantly reduced comparing to RA patients and HCs. In contrast to HCs, like RA patients, individuals at high-risk for RA showed a reduction in the abundance of genus Defluviitaleaceae_UCG-011 and the species Neisseria oralis, but an expansion of Prevotella_6. Unexpectedly, the relative abundance of Porphyromonas gingivalis, reported as opportunistic pathogens for RA development, was significantly decreased in high-risk individuals. Additionally, we identified four genera in the saliva from high-risk individuals positively correlated with serum ACPA titers, and the other two genera inversely displayed. In summary, we observed a characteristic compositional change of salivary microbes in individuals at high-risk for RA, suggesting that oral microbiota dysbiosis occurs in the "pre-clinical" stage of RA and are correlated with systemic autoimmune features.


Asunto(s)
Artritis Reumatoide/epidemiología , Disbiosis/complicaciones , Interacciones Microbiota-Huesped , Boca/microbiología , Bacterias/clasificación , Bacterias/genética , Biodiversidad , Estudios de Casos y Controles , China , Femenino , Humanos , Masculino , Metagenómica , Persona de Mediana Edad , ARN Ribosómico 16S/genética , Medición de Riesgo
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