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1.
Virol J ; 18(1): 122, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34108000

RESUMEN

Using viral metagenomics, viral nucleic acid in 30 respiratory secretion samples collected from children with unknown etiological acute respiratory disease were investigated. Sequences showing similarity to human parainfluenza virus 1, anellovirus, bocavirus, coxsackievirus A4, human parechovirus (HPeV), and alphaflexivirus were recovered from these samples. Complete genomes of one anellovirus, one coxsackievirus A4, three parechoviruses were determined from these libraries. The anellovirus (MW267851) phylogenetically clustered with an unpublished anellovirus (MK212032) from respiratory sample of a Vietnamese patient, forming a separate branch neighboring to strains within the genus Betatorquevirus. The genome of coxsackievirus A4 (MW267852) shares the highest sequence identity of 96.4% to a coxsackievirus A4 (MN964079) which was identified in clinical samples from children with Hand, Foot, and Mouth Disease (HFMD). Two (MW267853 and MW267854) of the three parechoviruses belong to HPeV-1 and the other one (MW267855) belongs to HPeV-6. Recombination analysis indicated that an HPeV-1 (MW267854) identified in this study is a putative recombinant occurred between HPeV-1 and HPeV-3. Whether these viruses have association with specific respiratory disease calls for further investigation.


Asunto(s)
Parechovirus , Infecciones por Picornaviridae , Enfermedades Respiratorias , Viroma , Niño , Genoma Viral , Humanos , Parechovirus/genética , Filogenia , Infecciones por Picornaviridae/diagnóstico , ARN Viral , Enfermedades Respiratorias/diagnóstico , Enfermedades Respiratorias/virología , Análisis de Secuencia de ADN
2.
JAMA ; 325(1): 50-58, 2021 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-33300950

RESUMEN

Importance: Among all subtypes of breast cancer, triple-negative breast cancer has a relatively high relapse rate and poor outcome after standard treatment. Effective strategies to reduce the risk of relapse and death are needed. Objective: To evaluate the efficacy and adverse effects of low-dose capecitabine maintenance after standard adjuvant chemotherapy in early-stage triple-negative breast cancer. Design, Setting, and Participants: Randomized clinical trial conducted at 13 academic centers and clinical sites in China from April 2010 to December 2016 and final date of follow-up was April 30, 2020. Patients (n = 443) had early-stage triple-negative breast cancer and had completed standard adjuvant chemotherapy. Interventions: Eligible patients were randomized 1:1 to receive capecitabine (n = 222) at a dose of 650 mg/m2 twice a day by mouth for 1 year without interruption or to observation (n = 221) after completion of standard adjuvant chemotherapy. Main Outcomes and Measures: The primary end point was disease-free survival. Secondary end points included distant disease-free survival, overall survival, locoregional recurrence-free survival, and adverse events. Results: Among 443 women who were randomized, 434 were included in the full analysis set (mean [SD] age, 46 [9.9] years; T1/T2 stage, 93.1%; node-negative, 61.8%) (98.0% completed the trial). After a median follow-up of 61 months (interquartile range, 44-82), 94 events were observed, including 38 events (37 recurrences and 32 deaths) in the capecitabine group and 56 events (56 recurrences and 40 deaths) in the observation group. The estimated 5-year disease-free survival was 82.8% in the capecitabine group and 73.0% in the observation group (hazard ratio [HR] for risk of recurrence or death, 0.64 [95% CI, 0.42-0.95]; P = .03). In the capecitabine group vs the observation group, the estimated 5-year distant disease-free survival was 85.8% vs 75.8% (HR for risk of distant metastasis or death, 0.60 [95% CI, 0.38-0.92]; P = .02), the estimated 5-year overall survival was 85.5% vs 81.3% (HR for risk of death, 0.75 [95% CI, 0.47-1.19]; P = .22), and the estimated 5-year locoregional recurrence-free survival was 85.0% vs 80.8% (HR for risk of locoregional recurrence or death, 0.72 [95% CI, 0.46-1.13]; P = .15). The most common capecitabine-related adverse event was hand-foot syndrome (45.2%), with 7.7% of patients experiencing a grade 3 event. Conclusions and Relevance: Among women with early-stage triple-negative breast cancer who received standard adjuvant treatment, low-dose capecitabine maintenance therapy for 1 year, compared with observation, resulted in significantly improved 5-year disease-free survival. Trial Registration: ClinicalTrials.gov Identifier: NCT01112826.


Asunto(s)
Capecitabina/administración & dosificación , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Adulto , Capecitabina/efectos adversos , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Esquema de Medicación , Femenino , Estudios de Seguimiento , Síndrome Mano-Pie/etiología , Humanos , Quimioterapia de Mantención , Mastectomía , Persona de Mediana Edad , Clasificación del Tumor , Estadificación de Neoplasias , Neoplasia Residual , Observación , Neoplasias de la Mama Triple Negativas/mortalidad , Neoplasias de la Mama Triple Negativas/patología , Neoplasias de la Mama Triple Negativas/cirugía
3.
Int J Syst Evol Microbiol ; 70(1): 624-630, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31697226

RESUMEN

A novel Vogesella strain, YM-1T, was recovered from human urine in PR China in 2017. Cells of strain YM-1T were Gram-stain-negative, rod-shaped, aerobic, motile, non-spore-forming and poly-ß-hydroxybutyrate-accumulating. The strain contained C16:1ω6c/C 16:1ω7c, C16:0 and C18:0ω7c as major fatty acids; phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol and an unidentified phospholipid as major polar lipids; and ubiquinone-8 as the predominant respiratory quinone. Comparison of 16S rRNA gene sequences indicated that this strain had highest similarities to Vogesella perlucida DS-28T (98.8 %) and Vogesella mureinivorans 389T (98.1 %). The results of phylogenetic analysis based on the 16S rRNA gene sequences revealed that the novel strain was clustered and well separated with V. perlucida DS-28T and V. mureinivorans 389T within the genus Vogesella. The average nucleotide identity (ANI) and amino acid identity (AAI) analyses showed that this strain was not identified as V. perlucida DS-28T or V. mureinivorans 389T, with values well below the threshold limit for species demarcation (ANI <88.1 %, AAI <88.6 %). Based on the above results, strain YM-1T is proposed to be a novel species of the genus Vogesella with the name Vogesella urethralis sp. nov. (YM-1T=NBRC 113779=CGMCC 1.17135).


Asunto(s)
Betaproteobacteria/clasificación , Filogenia , Orina/microbiología , Bacterias Aerobias/genética , Técnicas de Tipificación Bacteriana , Composición de Base , Betaproteobacteria/aislamiento & purificación , China , ADN Bacteriano/genética , Ácidos Grasos/química , Humanos , Hidroxibutiratos/metabolismo , Hibridación de Ácido Nucleico , Fosfolípidos/química , Poliésteres/metabolismo , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
4.
Mol Biol Rep ; 47(8): 5997-6007, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32710389

RESUMEN

Heat shock factors (HSFs) play crucial roles in various plant stress responses. However, the current knowledge about HSFs in cassava, an important crop, is still insufficient. In this research, we identified 32 cassava HSF genes (MeHSFs) and clustered them into three groups (A, B, C) based on phylogenetic analysis and structural characteristics. Conserved motif analyses showed that MeHSFs display domains characteristic to HSF transcription factors. Gene structure analyses suggested that 29 MeHSFs contained only two exons. All identified 32 cassava MeHSFs were distributed on 13 chromosomes. Their expression profiles revealed that the different MeHSFs were expressed differentially in different tissues, most high expression genes belonged to group A. The similar MeHSFs were up-regulated after treatment with both PEG and abscisic acid (ABA), which implied that these MeHSFs may participate in resistance to simulated drought stress associated with the ABA signaling pathway. In addition, several MeHSFs were induced during postharvest physiological deterioration (PPD) in cassava. Our results provided basic but important knowledge for future gene function analysis of MeHSFs toward efforts in improving tolerance to abiotic stress and PPD in cassava.


Asunto(s)
Sequías , Genes de Plantas , Factores de Transcripción del Choque Térmico/biosíntesis , Manihot/genética , Proteínas de Plantas/biosíntesis , Estrés Fisiológico/genética , Ácido Abscísico/farmacología , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Mapeo Cromosómico , Cromosomas de las Plantas/genética , Exones/genética , Almacenamiento de Alimentos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Factores de Transcripción del Choque Térmico/química , Factores de Transcripción del Choque Térmico/genética , Intrones/genética , Manihot/metabolismo , Especificidad de Órganos , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/genética , Raíces de Plantas/metabolismo , Polietilenglicoles/farmacología , Homología de Secuencia de Aminoácido , Especificidad de la Especie
5.
Biomacromolecules ; 15(11): 4260-71, 2014 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-25287757

RESUMEN

A fully biobased and supertough thermoplastic vulcanizate (TPV) consisting of polylactide (PLA) and a biobased vulcanized unsaturated aliphatic polyester elastomer (UPE) was fabricated via peroxide-induced dynamic vulcanization. Interfacial compatibilization between PLA and UPE took place during dynamic vulcanization, which was confirmed by gel measurement and NMR analysis. After vulcanization, the TPV exhibited a quasi cocontinuous morphology with vulcanized UPE compactly dispersed in PLA matrix, which was different from the pristine PLA/UPE blend, exhibiting typically phase-separated morphology with unvulcanized UPE droplets discretely dispersed in matrix. The TPV showed significantly improved tensile and impact toughness with values up to about 99.3 MJ/m(3) and 586.6 J/m, respectively, compared to those of 3.2 MJ/m(3) and 16.8 J/m for neat PLA, respectively. The toughening mechanisms under tensile and impact tests were investigated and deduced as massive shear yielding of the PLA matrix triggered by internal cavitation of VUPE. The fully biobased supertough PLA vulcanizate could serve as a promising alternative to traditional commodity plastics.


Asunto(s)
Materiales Biocompatibles/química , Plásticos Biodegradables/química , Peróxidos/química , Poliésteres/química , Elastómeros/química
6.
Cleft Palate Craniofac J ; 51(1): 23-9, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22849639

RESUMEN

OBJECTIVES: This study was conducted to measure the soft tissue of the alar base and the piriform aperture area of the maxillary bone of unilateral cleft lips with secondary nasal deformities when secondary operation are necessary to classify the alar base depression and to provide a clinical reference for the second surgery. METHODS: Twenty-six patients with unilateral cleft lip with secondary nasal deformity were treated at the Department of Oral and Maxillofacial Surgery, School of Stomatology, China Medial University. Nose data were attained preoperatively and postoperatively. Correlations were made between the soft tissue and the bony depression and patient satisfaction with the nasi basis. Classifications were then made based on these data. RESULTS: When the distance discrepancy of the bilateral piriform aperture depression was less than 4.5 mm, we obtained a fine appearance for the nose by repairing only the soft tissues. When it was more than 5 mm, we had to combine repair of the soft tissue with a bone graft or the restitution of the alveolar cleft. When the distance was between 4.5 mm and 5 mm, the surgeon considered both the wishes of the patient and the clinic's standard procedure. CONCLUSIONS: For patients with cleft lips and palates, the bony depression was not the only factor that resulted in postoperative alar depression. Anthropometry of the nose prior to surgery was important for choosing the methods that would yield satisfactory results.


Asunto(s)
Antropometría , Labio Leporino/clasificación , Labio Leporino/cirugía , Maxilar/anomalías , Maxilar/cirugía , Nariz/anomalías , Nariz/cirugía , Adolescente , Adulto , Niño , China , Femenino , Humanos , Masculino , Rinoplastia
7.
Avian Pathol ; 42(4): 335-41, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23782167

RESUMEN

This experiment was performed to explore the relationship between 5-hydroxytryptamine (5-HT) levels in pulmonary arterioles and in pulmonary vascular remodelling in broilers. Pulmonary arterial hypertension was induced by injecting cellulose microparticles intravenously. Pulmonary hypertension syndrome (PHS) morbidity, right ventricle/total ventricle weight ratio (RV/TV), packed cell volume (PCV), haemoglobin concentration (HB), vessel wall area to vessel total area ratio (WA/TA) and mean tunica media thickness in pulmonary arterioles (mMTPA) were measured. Proliferating cell nuclear antigen (PCNA), argyrophilic nucleolar organizer region proteins (Ag-NORs) and 5-HT content in pulmonary arterioles were determined. The results showed that injecting cellulose microparticles intravenously in broilers could successfully increase the PHS morbidity, significantly elevate RV/TV, PCV and HB, significantly increase mMTPA and WA/TA, and significantly increase the argyrophilic particles in smooth muscle cell nucleoli, PCNA-positive cells in the medial layer, and the 5-HT content in pulmonary arterioles. Correlation analysis showed that the level of 5-HT was strongly positively correlated with PCNA and Ag-NORs. The results indicated that the increase of 5-HT in the tunica media could possibly promote the proliferation of smooth muscle cells in pulmonary arterioles and thus the occurrence of pulmonary vascular remodelling.


Asunto(s)
Arteriolas/metabolismo , Pollos , Hipertensión Pulmonar/veterinaria , Pulmón/irrigación sanguínea , Neovascularización Fisiológica/fisiología , Enfermedades de las Aves de Corral/metabolismo , Serotonina/metabolismo , Animales , Celulosa/administración & dosificación , Hematócrito , Hemoglobinas/metabolismo , Hipertensión Pulmonar/metabolismo , Antígeno Nuclear de Célula en Proliferación/metabolismo , Túnica Media/metabolismo
8.
Int J Biol Macromol ; 236: 123960, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-36921823

RESUMEN

Biobased poly(lactic acid)/lignin (PLA/lignin) composites are limited by poor mechanical properties resulted from poor compatibility and low interfacial adhesion. Herein, we reported a novel approach to improve compatibility and interfacial adhesion of PLA/lignin composites via reactive compatibilization with epoxidized natural rubber (ENR) as a compatibilizer. Interfacial tension calculation indicated that lignin tended to act as interfacial phase between PLA and ENR, but morphology analysis demonstrated lignin was wrapped with a layer of ENR and dispersed in PLA matrix, which was attributed to the interfacial reaction of ENR with both PLA and lignin. The interfacial reaction was confirmed by Fourier transform infrared spectroscopy. The compatibility and interfacial adhesion between PLA and lignin were improved significantly by incorporation and increase in the content of ENR, as evidenced by the reduced interfacial gaps, blurry phase boundaries, and enhanced elastic response. As such, the mechanical properties of PLA/lignin composites were enhanced significantly. The tensile strength and elongation at break of PLA/lignin (W/W, 80/20) were improved by 15 % and 77 %, respectively, with the incorporation of only 1 wt% ENR. We believe this approach to compatibilize PLA/lignin composites is promising because it would not require costly modification of lignin and would not compromise the sustainability of composites.


Asunto(s)
Lignina , Goma , Lignina/química , Goma/química , Poliésteres/química , Resistencia a la Tracción
9.
Int J Biol Macromol ; 244: 125202, 2023 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-37270117

RESUMEN

Cellulose nanocrystal (CNC) shows great potential in reinforced composites but it is difficult to disperse in epoxy thermosets due to its poor dispersity in epoxy monomers. Herein, we reported a novel approach to disperse CNC in epoxidized soybean oil (ESO)-derived epoxy thermosets uniformly by using the reversibility of dynamic imine-containing ESO-derived covalent adaptable network (CAN). The crosslinked CAN was deconstructed by an exchange reaction with ethylenediamine (EDA) in dimethyl formamide (DMF), leading to a solution of deconstructed CAN with plenty of hydroxyl and amino groups, which could form strong hydrogen bonds with hydroxyl groups of CNC and thus facilitated and stabilized dispersion of CNC in the deconstructed CAN solution. Epoxy composite with well-dispersed CNC was finally achieved by a reformation of CAN through the removal of DMF and EDA. In this way, the epoxy composites with CNC content up to 30 wt% were successfully prepared and showed drastically reinforced mechanical properties. The tensile strength and Young's modulus of the CAN were improved by up to ∼70 % and ∼45 times with the incorporation of 20 and 30 wt% CNC, respectively. The composites showed excellent reprocessability without significant loss in mechanical properties after reprocessing.


Asunto(s)
Celulosa , Nanopartículas , Celulosa/química , Resistencia a la Tracción , Módulo de Elasticidad , Nanopartículas/química , Resinas Epoxi
10.
Zhonghua Wai Ke Za Zhi ; 50(4): 338-41, 2012 Apr.
Artículo en Zh | MEDLINE | ID: mdl-22800787

RESUMEN

OBJECTIVE: To initially evaluate the application of artificial vertebra of n-HA/PA66 in anterior reconstruction of lower cervical spine fracture and dislocation. METHODS: In this study, 84 patients with lower cervical spine fracture and dislocation received anterior cervical discectomy, spinal canal decompression or subtotal corpectomy, spinal canal decompression and reconstruction by n-HA/PA66 composite artificial vertebral body combined with plate instrumentation. Neurological function was followed up by improvement rate of Frankel and situations of the supporting body was observed by X ray and 3D-CT in 3, 12, 24 months postoperatively. The intervertebral height, physical arc (reflected by Cobb angle) and the locations and fusion rate of the supporting body were assessed in order to evaluate the stability of the cervical spine and alignment improvements. RESULTS: All the patients underwent operation successfully and were followed up for 6 to 24 months with an average of 12 months. The preoperative symptoms were improved to varying degrees. Imaging studies showed that in all cases graft fusion were achieved, and cervical alignments, intervertebral height, cervical spine stability and the locations of the artificial vertebral body were well maintained. No displacement and subsidence of the artificial vertebral body occurred. Postoperative immediate intervertebral height (2.4 ± 0.2) cm, preoperative intervertebral height (1.9 ± 0.1) cm, comparisons of the two groups was statistically significant (q = 2.48, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group intervertebral height was not statistically significant (P > 0.05). Preoperative Cobb angle was 9.8° ± 1.2°, postoperative immediate Cobb angle was 16.6° ± 1.2°, comparisons of the two groups was statistically significant (q = 14.25, P < 0.001). The immediate, 3 month, 1 year, 2 year period follow-up group Cobb angle was not statistically significant (P > 0.05). CONCLUSIONS: n-HA/PA66 artificial vertebral body can provide early cervical spine support and stability and effectively maintain the biological alignment and cervical intervertebral height. It has high rate of graft fusion and is convenient to observe by X-ray. Therefore, n-HA/PA66 can be taken as an ideal graft for anterior lower cervical spine fracture and dislocation operation, but further follow-up study is still required to evaluate the long-term effects.


Asunto(s)
Sustitutos de Huesos , Vértebras Cervicales/lesiones , Nanoestructuras , Fracturas de la Columna Vertebral/cirugía , Fusión Vertebral/instrumentación , Adolescente , Adulto , Anciano , Vértebras Cervicales/cirugía , Descompresión Quirúrgica , Femenino , Estudios de Seguimiento , Fijación Interna de Fracturas , Humanos , Hidroxiapatitas , Luxaciones Articulares/complicaciones , Luxaciones Articulares/cirugía , Masculino , Persona de Mediana Edad , Nylons , Fracturas de la Columna Vertebral/complicaciones , Adulto Joven
11.
Eur Spine J ; 20(12): 2240-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21544594

RESUMEN

Biodegradable copolymer α-TCP/poly(amino acid) composite artificial lamina was prepared and used in goat cervical vertebra resection repair. Cervical 4 was removed by laminectomy, and a vertebra defect of 27 × 9 mm was made. α-TCP/poly(amino acid) composite artificial lamina was inserted in the test group. The efficiency of the copolymer during repair and reconstruction of the goats' vertebra was tested by using X-ray, CT scanning, and histological and biomechanical measurements. In the 24 weeks following the operation, the artificial lamina refrained from shifting, and no dural adhesion pressure was observed. In contrast, the control group suffered from infiltration of soft tissue in the spinal canal, dural pressure and α-TCP/poly(amino acid) degradation. In conclusion, α-TCP/poly(amino acid) composite artificial lamina can significantly prevent scar tissue from infiltrating the spinal canal.


Asunto(s)
Implantes Absorbibles , Materiales Biocompatibles , Vértebras Cervicales/cirugía , Cicatriz/prevención & control , Enfermedades de la Columna Vertebral/prevención & control , Animales , Cabras , Polímeros , Adherencias Tisulares/prevención & control , Cicatrización de Heridas
12.
J Adv Prosthodont ; 13(1): 55-64, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33747395

RESUMEN

PURPOSE: To investigate the biomechanical effect of marginal bone resorption (MBR) on the mandibular mini implant (MI)-retained overdenture (MI-OD) on the edentulous model. MATERIALS AND METHODS: The experimental mandibular edentulous model was modified from a commercial model with 2 mm thick artificial soft tissue under denture base. Two MIs (Φ2.6 mm × 10 mm) were bilaterally placed between the lateral incisor and the canine area and attached with magnetic attachments. Three groups were set up as follows: 1) alveolar bone around the MI without MBR (normal group), 2) with MBR to 1/2 the length of the implant (resorption group), and 3) complete denture (CD) without MI (CD group). Strain around the MI, pressure near the first molar area, and displacement of denture were simultaneously measured, loading up to 50 N under bilateral/unilateral loading. Statistical analysis was performed using independent-samples t test and one-way ANOVA (α=.05). RESULTS: The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure in CD was higher than in MI-ODs (P <.05), while there was no statistical difference between the normal and resorption group (P >.05). Similarly, the CD demonstrated a greater displacement of the denture base than did the MI-ODs during bilateral and unilateral loadings (P <.05). CONCLUSION: The strain around the MI with MBR was approximately 1.5 times higher than that without MBR. The pressure on posterior alveolar ridge and denture displacement of MI-ODs significantly decreased compared to CDs, even when MBR occurs. Bilateral balanced occlusion was recommended for MI-ODs, especially when MBR occurred.

13.
Water Environ Res ; 92(1): 115-122, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31424587

RESUMEN

A high-performance bagasse-based adsorbent was prepared from agricultural waste bagasse by grafting of acrylamide and aminating with diethylenetriamine. Effects of catalyst dosage, acrylamide concentration, reaction temperature, and bath ratio on the grafting yield were investigated. The adsorption performances for mercury ions were evaluated by batch adsorption experiments and kinetic experiments. The results show that the adsorbent has high adsorption capacity for mercury in a wide range of pH values. The adsorption capacity could be as high as 813.0 mg/g, and the removal percentage for mercury ions can reach 99.9%. The kinetic adsorption experiments show it can achieve adsorption equilibrium rapidly, which implies that the adsorbent has a strong ability to capture mercury ions. Besides, the bagasse-based adsorbent showed promising regeneration performance, and its adsorption amount of regenerated adsorbent only slightly decreased after five recycling. PRACTITIONER POINTS: An amino-rich adsorbent was prepared from bagasse. The adsorbent possesses high adsorption capacity and high removal efficiency for mercury. The aminated bagasse adsorbs mercury rapidly. The adsorbent functionalized with amino possesses strong affinity toward mercury.


Asunto(s)
Mercurio , Contaminantes Químicos del Agua , Purificación del Agua , Adsorción , Celulosa , Concentración de Iones de Hidrógeno , Iones , Cinética
14.
Carbohydr Polym ; 244: 116449, 2020 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-32536394

RESUMEN

Superhydrophilic and underwater superoleophobic textiles exhibit excellent oil/water separation performance but are limited by the poor stability and environmental incompatibility. Inspired by strong adhesion of marine mussels, we designed and fabricated a stable and eco-friendly superhydrophilic and underwater superoleophobic cotton fabric (CF) from all renewable resources through in-situ surface deposition of polydopamine (PDA) particles followed by adsorption of hydrophilic chitosan via dip coating at room temperature. The as-prepared superhydrophilic and underwater superoleophobic CF exhibited outstanding oil/water separation performance with separation efficiency and water flux higher than 99 % and 15,000 L m-2 h-1, respectively. Moreover, it not only showed excellent resistance to mechanical abrasion and ultrasound treatment but also had outstanding superwetting stability against acid/alkali/salt erosion. We believed that the eco-friendly superhydrophilic and underwater superoleophobic CF would exhibit great potential in oil/water separation especially under harsh conditions.


Asunto(s)
Quitosano/química , Fibra de Algodón , Indoles/química , Polímeros/química , Purificación del Agua , Emulsiones/química , Filtración , Aceites/química
15.
Zhongguo Gu Shang ; 33(11): 1022-6, 2020 Nov 25.
Artículo en Zh | MEDLINE | ID: mdl-33269851

RESUMEN

Periprosthetic infection after hip replacement is a clinical catastrophic disease, which often leads to the failure of the prosthesis. It needs the combination of systemic antibiotics to cure the infection, which brings huge burden to doctors and patients. There are strict indications for debridement and one-stage revision of the prosthesis, and few cases meet the requirements. The second revision is still the gold standard for the treatment of periprosthetic infection. It is suitable for all infection conditions and has a high success rate. On the second phase of renovation, the antibiotic sustained release system plays a key role, and the carrier of antibiotic sustained-release system is the focus of current research, including classic bone cement and absorbable biomaterials. Bone cement has strong mechanical strength, but the antibiotic release shows a sharp decline trend; the absorbable biomaterials can continuously release antibiotics with high concentration, but the mechanical strength is poor, so it could not use alone. The combination of bone cement and absorbable biomaterials will be an ideal antibiotic carrier. PMMA is the most commonly used antibiotic carrier, but the antibiotic release concentration is decreased sharply after 24 hours. It will be difficult to control the infection and increase the risk of bacterial resistance if it is lower than the minimum inhibitory concentration. The biodegradable materials can release antibiotics completely, with long release time and high concentration, but low mechanical strength. Antibiotic spacer plays an important role in the control of infection. In the future, how to further extend the antibiotic release time of antibiotic sustained-release system, increase the amount of antibiotic release and maintain the mechanical strength of the material will be studied.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Infecciones Relacionadas con Prótesis , Antibacterianos/uso terapéutico , Artroplastia de Reemplazo de Cadera/efectos adversos , Cementos para Huesos , Humanos , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , Infecciones Relacionadas con Prótesis/cirugía , Reoperación
16.
Biomacromolecules ; 9(11): 3157-64, 2008 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18937401

RESUMEN

A novel environmentally friendly thermoplastic soy protein/polyester blend was successfully prepared by blending soy protein isolate (SPI) with poly(butylene succinate) (PBS). To improve the compatibility between SPI and PBS, the polyester was pretreated by introducing different amounts of urethane and isocyanate groups before blending. The blends containing pretreated PBS showed much finer phase structures because of good dispersion of polyester in protein. Consequently, the tensile strength and modulus of blends increased obviously. A lower glass transition temperature of protein in the blends than that of the pure SPI, which was caused by the improvement of the compatibility between two phases, was observed by dynamic mechanical analyzer (DMA). The hydrophobicity, water resistance, and moisture absorption at different humidities of the blends were modified significantly due to the incorporation of PBS.


Asunto(s)
Butileno Glicoles/química , Polímeros/síntesis química , Proteínas de Soja/química , Interacciones Hidrofóbicas e Hidrofílicas , Transición de Fase , Polímeros/química , Conformación Proteica , Resistencia a la Tracción
17.
Int J Biol Macromol ; 115: 786-791, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29702166

RESUMEN

Development of biodegradable polyurethane materials is the most promising in the wider context of the "greening" of industrial chemistry. To tackle this challenge, a novel biodegradable polyurethane foam from all bioresource-based polyols (lignin and soy oil-derived polyols) and polymeric methyldiphenyl diisocyanate (pMDI) have been synthesized via a one-pot and self-rising process. All these foam samples have the internal cellular morphology and microstructure. FTIR result exhibits characteristic peaks of polyurethane, and indicates covalent bonds between soy-based polyurethane and lignin, and the lignin powders can react with pMDI via active -H and -CNO. In addition, hydrogen bonding also plays an important role in forming the 3D structures. These interactions and chemical bonds made the prepared foam samples form the 3D macromolecular structure with improved mechanical, thermal, and biodegradable properties. The reaction process is time-saving and cost-effective as it requires no blowing agent and minimum processing steps, while exploring the potential of using the higher content of nature bioresource constituents.


Asunto(s)
Lignina/química , Fenómenos Mecánicos , Polímeros/química , Poliuretanos/química , Aceite de Soja/química , Tecnología Química Verde , Poliuretanos/metabolismo
18.
Int J Biol Sci ; 12(6): 653-66, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27194943

RESUMEN

The dwarfing mechanism of Rht-dp in dwarf Polish wheat (DPW) is unknown. Each internode of DPW was significantly shorter than it in high Polish wheat (HPW), and the dwarfism was insensitive to photoperiod, abscisic acid (ABA), gibberellin (GA), cytokinin (CK), auxin and brassinolide (BR). To understand the mechanism, three sets of transcripts, DPW, HPW, and a chimeric set (a combination of DPW and HPW), were constructed using RNA sequencing (RNA-Seq). Based on the chimeric transcripts, 2,446 proteins were identified using isobaric tags for relative and absolute quantification (iTRAQ). A total of 108 unigenes and 12 proteins were considered as dwarfism-related differentially expressed genes (DEGs) and differentially expressed proteins (DEPs), respectively. Among of these DEGs and DEPs, 6 DEGs and 6 DEPs were found to be involved in flavonoid and S-adenosyl-methionine (SAM) metabolisms; 5 DEGs and 3 DEPs were involved in cellulose metabolism, cell wall plasticity and cell expansion; 2 DEGs were auxin transporters; 2 DEPs were histones; 1 DEP was a peroxidase. These DEGs and DEPs reduced lignin and cellulose contents, increased flavonoid content, possibly decreased S-adenosyl-methionine (SAM) and polyamine contents and increased S-adenosyl-L-homocysteine hydrolase (SAHH) content in DPW stems, which could limit auxin transport and reduce extensibility of the cell wall, finally limited cell expansion (the cell size of DPW was significantly smaller than HPW cells) and caused dwarfism in DPW.


Asunto(s)
ARN de Planta/análisis , Análisis de Secuencia de ARN/métodos , Triticum/genética , Triticum/metabolismo , Ácido Abscísico/metabolismo , Brasinoesteroides/metabolismo , Celulosa/metabolismo , Citocininas/metabolismo , Flavonoides/metabolismo , Regulación de la Expresión Génica de las Plantas/genética , Regulación de la Expresión Génica de las Plantas/fisiología , Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , ARN de Planta/genética , Esteroides Heterocíclicos/metabolismo
19.
Bioresour Technol ; 194: 403-6, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26216781

RESUMEN

Development of highly cost-effective, highly operation-convenient and highly efficient natural polymer-based adsorbents for their biodegradability and biocompatibility, and supply of safe drinking water are the most threatening problems in water treatment field. To tackle the challenges, a new kind of efficient recyclable magnetic chitosan/cellulose hybrid microspheres was prepared by sol-gel method. By embedding magnetic γ-Fe2O3 nanoparticles in chitosan/cellulose matrix drops in NaOH/urea aqueous solution, it combined renewability and biocompatibility of chitosan and cellulose as well as magnetic properties of γ-Fe2O3 to create a hybrid system in heavy metal ions removal.


Asunto(s)
Celulosa/química , Quitosano/química , Metales Pesados/química , Microesferas , Contaminantes Químicos del Agua/química , Adsorción , Materiales Biocompatibles/química , Cadmio/química , Cobre/química , Compuestos Férricos , Concentración de Iones de Hidrógeno , Cinética , Plomo/química , Magnetismo , Nanopartículas , Hidróxido de Sodio/química , Electricidad Estática , Temperatura , Urea/química , Agua/química , Purificación del Agua
20.
PLoS One ; 9(5): e96537, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24816840

RESUMEN

Bioactive gibberellins (GAs) comprise an important class of natural plant growth regulators and play essential roles in cotton fiber development. To date, the molecular base of GAs' functions in fiber development is largely unclear. To address this question, the endogenous bioactive GA levels in cotton developing fibers were elevated by specifically up-regulating GA 20-oxidase and suppressing GA 2-oxidase via transgenic methods. Higher GA levels in transgenic cotton fibers significantly increased micronaire values, 1000-fiber weight, cell wall thickness and cellulose contents of mature fibers. Quantitative RT-PCR and biochemical analysis revealed that the transcription of sucrose synthase gene GhSusA1 and sucrose synthase activities were significantly enhanced in GA overproducing transgenic fibers, compared to the wild-type cotton. In addition, exogenous application of bioactive GA could promote GhSusA1 expression in cultured fibers, as well as in cotton hypocotyls. Our results suggested that bioactive GAs promoted secondary cell wall deposition in cotton fibers by enhancing sucrose synthase expression.


Asunto(s)
Pared Celular/enzimología , Fibra de Algodón/normas , Giberelinas/metabolismo , Glucosiltransferasas/metabolismo , Gossypium/enzimología , Proteínas de Plantas/metabolismo , Secuencia de Aminoácidos , Pared Celular/genética , Celulosa/biosíntesis , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Giberelinas/farmacología , Glucosiltransferasas/clasificación , Glucosiltransferasas/genética , Gossypium/genética , Hipocótilo/enzimología , Hipocótilo/genética , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Datos de Secuencia Molecular , Filogenia , Reguladores del Crecimiento de las Plantas/metabolismo , Reguladores del Crecimiento de las Plantas/farmacología , Proteínas de Plantas/clasificación , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Interferencia de ARN , Homología de Secuencia de Aminoácido
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