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1.
Physiol Genomics ; 55(3): 147-153, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36847439

RESUMEN

Neijiang (NJ) and Yacha (YC) are two indigenous pig breeds in the Sichuan basin of China, displaying higher resistance to diseases, lower lean ratio, and slower growth rate than the commercial Western pig breed Yorkshire (YS). The molecular mechanisms underlying the differences in growth and development between these pig breeds are still unknown. In the present study, five pigs from NJ, YC, and YS breeds were subjected to the whole genome resequencing, and then the differential single-nucleotide polymorphisms (SNPs) were screened using a 10-kb window sliding in 1-kb step using the Fst method. Finally, 48,924, 48,543, and 46,228 nonsynonymous single-nucleotide polymorphism loci (nsSNPs) were identified between NJ and YS, NJ and YC, and YC and YS, which highly or moderately affected 2,490, 800, and 444 genes, respectively. Moreover, three nsSNPs were detected in the genes of acetyl-CoA acetyltransferase 1 (ACAT1) insulin-like growth factor 2 receptor (IGF2R), insulin-like growth factor 2 and mRNA-binding protein 3 (IGF2BP3), which potentially affected the transformation of acetyl-CoA to acetoacetyl-CoA and the normal functions of the insulin signaling pathways. Moreover, serous determinations revealed significantly lower acetyl-CoA content in YC than in YS, supporting that ACAT1 might be a reason explaining the differences in growth and development between YC and YS breeds. Contents of phosphatidylcholine (PC) and phosphatidic acid (PA) significantly differed between the pig breeds, suggesting that glycerophospholipid metabolism might be another reason for the differences between Chinese and Western pig breeds. Overall, these results might contribute basic information to understand the genetic differences determining the phenotypical traits in pigs.


Asunto(s)
Porcinos , Animales , Acetilcoenzima A , Genoma , Polimorfismo de Nucleótido Simple , Porcinos/genética , Porcinos/crecimiento & desarrollo
2.
Environ Monit Assess ; 193(6): 371, 2021 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-34059982

RESUMEN

Several epidemiological studies with small sample sizes have suggested that hair is a promising biomarker of exposure to polybrominated diphenyl ethers (PBDEs). We reanalyzed the data from human studies to investigate correlations between the concentrations of the five main congeners in hair and serum. We searched medical article databases for articles that reported correlation coefficients for concentrations of PBDEs in hair and serum. The methodological quality of the included articles was fully assessed. Then, the correlation coefficients were used for our analysis. Seven epidemiological studies were included in our analysis using the random-effects model. Significant positive relationships were found between the concentrations of the five congeners (BDE28, BDE47, BDE99, BDE100, BDE209) in serum and hair. The results of this study show that hair may be a promising biomarker for the biomonitoring human exposure to the five congeners of PBDEs within a certain detection range. Studies with a larger sample size are needed to explore the detection range.


Asunto(s)
Disruptores Endocrinos , Éteres Difenilos Halogenados , Biomarcadores , Monitoreo del Ambiente , Cabello/química , Éteres Difenilos Halogenados/análisis , Humanos
3.
Biomacromolecules ; 21(4): 1351-1367, 2020 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-32202418

RESUMEN

Chitosan (CS), a natural biopolymer, has been extensively explored for multiple applications including tissue engineering, gene therapy, bioimaging, and sewage treatment due to its abundant availability, intrinsic biocompatibility, biodegradability, and tunable biological properties. Nevertheless, the actual use of CS is limited because of its water-insolubility in physiological circumstances, which could be optimized by chemical modifications via active side groups. Etherification is one of the most widely used reactions to obtain water-soluble CS derivatives, such as hydroxybutyl CS (HBC). HBC, synthesized by grafting hydroxybutyl groups to the functional hydroxyl and amino groups of CS skeleton, has been demonstrated to possess superior biological properties over those of CS, especially satisfactory water solubility in neutral condition and reversible stimulus-response against external heat. Meanwhile, the unique characteristics of thermally sensitive "sol-gel" and "sol-micelle" transition have gained tremendous attention, which differ in heterogeneously and homogeneously synthesized HBC. Herein, we discuss the synthesis (heterogeneously and homogeneously) of HBC, favorable physiochemical properties of HBC, and HBC-centered biocomposites in a range of formulations or dosage forms such as sponges, gels, nanoparticles, nanofibers, and films. Meanwhile, we summarize the potential bioapplications and trends of HBC and HBC centered biocomposites and offer our perspectives on the plausible advances in this field in the near future.


Asunto(s)
Quitosano , Nanofibras , Nanopartículas , Quitosano/análogos & derivados , Ingeniería de Tejidos
4.
Biomater Sci ; 9(14): 4952-4967, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34075916

RESUMEN

In this study, an efficient composite hemostatic material (DA-diatom-T) was prepared, using a polydopamine layer as a linker to immobilize thrombin on the surface of diatom biosilica. DA-diatom-T retained the porous structure of the diatom with high water absorption capacity, which can absorb 31 times its own weight of water. The thrombin activity of DA-diatom-T was as high as 5.81 U mg-1 that could be maintained at 67% after 30 days at room temperature. DA-diatom-T exhibited non-toxicity to mouse fibroblast cell lines, favorable hemocompatibility and fast procoagulant ability. DA-diatom-T could promote the initiation of the coagulation process and increase platelet activity and blood clot strength to form a physical barrier at the wound. In an in vivo study, DA-diatom-T could significantly reduce the clotting time and reduce the bleeding volume. The above results showed that DA-diatom-T had potential as a new hemostatic material.


Asunto(s)
Diatomeas , Hemostáticos , Animales , Hemorragia/tratamiento farmacológico , Hemostáticos/farmacología , Indoles , Ratones , Polímeros , Trombina
5.
IEEE Trans Cybern ; 51(2): 815-828, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31567111

RESUMEN

With the development of social network platforms, discussion forums, and question answering websites, a huge number of short messages that typically contain a few words for an individual document are posted by online users. In these short messages, emotions are frequently embedded for communicating opinions, expressing friendship, and promoting influence. It is quite valuable to detect emotions from short messages, but the corresponding task suffers from the sparsity of feature space. In this article, we first generate term groups co-occurring in the same context to enrich the number of features. Then, two basic supervised topic models are proposed to associate emotions with topics accurately. To reduce the time cost of parameter estimation, we further propose an accelerated algorithm for our basic models. Extensive evaluations using three short corpora validate the efficiency and effectiveness of the accelerated models for predicting the emotions of unlabeled documents, in addition to generate the topic-level emotion lexicons.

6.
Int J Biol Macromol ; 147: 931-936, 2020 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-31739062

RESUMEN

The effect of NaOH/urea solution freeze-thaw pretreatment to the chitosan of purity and the degree of deacetylation from the crab shell was examined. Higher purity chitosan (CS1) was prepared. On this basis, the raw materials after the first demineralization were pretreated with NaOH/urea solution freeze-thaw under different freeze-thaw situations. The produced chitosans (CS1-CS4) were characterized in the ash content, solubility, protein content, degree of deacetylation, viscosity average molecular weight, SEM, FTIR, XRD, antimicrobial activity. The results showed that the freeze-thaw process had advantageous influence on decreasing the ash content and increasing degree of deacetylation and antibacterial activity. Moreover, the antibacterial property of the extracted chitosans seemed to be positively related to their degree of deacetylation. It is concluded that CS4 had the lowest ash content (0.052%), the highest degree of deacetylation (86.02%) and the greatest antibacterial activity. Therefore, we recommend CS4 as agent for industrial and pharmaceutical applications.


Asunto(s)
Braquiuros/química , Quitosano , Hidróxido de Sodio/química , Urea/química , Animales , Quitosano/química , Quitosano/aislamiento & purificación , Congelación
7.
Int J Biol Macromol ; 146: 99-109, 2020 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-31874265

RESUMEN

Biocompatibility and mechanical properties have always been important indicators for the application of hydrogel materials in tissue engineering. In this work, a high strength and toughness chitosan-poly (vinyl alcohol) (PVA) DN (double network) hydrogel based on multiple hydrogen bonding interactions was prepared by applying the simple freezing-heating alternate treatment to the chitosan-PVA alkaline solution. The PVA first network was prepared by freeze crystallization, and the chitosan second network was constructed by raising the chitosan/KOH/urea temperature to 45 °C. The dynamic hydrogen bonding presented in the first PVA network and the second chitosan network given the hydrogel superior compressive (60%-230 KPa), tensile (152 KPa-360%), recoverability (90.77% after 5 cycles) and anti-swelling properties. The results of in vitro cell compatibility and in vivo subcutaneous implantation in rats both indicated that the chitosan-PVA DN hydrogel had the ability to promote cell attachment and wound healing. This DN hydrogel based on hydrogen bonding is expected to be applied in the tissue engineering repair. In addition, the hydrogel preparation process is simple and non-toxic, which provides a reference for the production of green and safe tissue engineering hydrogels.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/química , Hidrogeles/química , Ensayo de Materiales , Alcohol Polivinílico/química , Ingeniería de Tejidos , Álcalis , Animales , Línea Celular , Enlace de Hidrógeno , Ratones , Ratas , Resistencia a la Tracción
8.
Adv Healthc Mater ; 9(21): e2000951, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-33006258

RESUMEN

Uncontrolled hemorrhage is the main reason of possible preventable death after accidental injury. It is necessary to develop a hemostatic agent with rapid hemostatic performance and good biocompatibility. In this study, a chitosan/diatom-biosilica-based aerogel is developed using dopamine as cross-linker by simple alkaline precipitation and tert-butyl alcohol replacement. The chitosan/diatom-biosilica aerogel exhibits favorable biocompatibility and multiscale hierarchical porous structure (from nanometer to micrometer), which can be controlled by the concentration of tert-butyl alcohol. The displacement of tert-butyl alcohol can keep the porosity of diatom-biosilica in aerogel and give it large surface with efficient water absorption ratio. 30% tert-butyl alcohol replacement of aerogel possesses the largest surface area (74.441 m2 g-1 ), water absorption capacity (316.83 ± 2.04%), and excellent hemostatic performance in vitro blood coagulation (≈70 s). Furthermore, this aerogel exhibits the shortest clotting time and lowest blood loss in rat hemorrhage model. The strong interface effect between aerogel and blood is able to promote erythrocytes aggregation, platelets adhesion, and activation, as well as, activate the intrinsic coagulation pathway to accelerate blood coagulation. All the above results demonstrate that chitosan/diatom-biosilica aerogel has great potential to be a safe and rapid hemostatic material.


Asunto(s)
Quitosano , Diatomeas , Hemostáticos , Animales , Quitosano/farmacología , Hemostasis , Hemostáticos/farmacología , Porosidad , Ratas
9.
Carbohydr Polym ; 236: 116067, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172882

RESUMEN

Stimuli-responsive gel volume variation is reversible and has shown promising applications, which may be potential for contraction or expansion fabrication, generating shrinking or swelling volume of the original. In this study, a thermo/photo dual-crosslinking hydrogel is prepared with methacrylated hydroxylbutyl chitosan (MHBC) and gelatin methacrylate (GelMA). The M/G hydrogel undergoes sol-gel phase transition under room temperature and shrinking deformation upon elevating temperature. Besides nontoxicity and biodegradability, dual crosslink endowed the composite hydrogel with strengthened and tunable mechanical property, controlled and repeatable contraction property in response to temperature elevation from 25 ℃ to 37 ℃, and enhanced cell adhesion in 3D culture. These peculiarities of M/G hydrogel provide great potential for application in contraction fabrication to acquire high resolution or small scale features that may be limited by fabrications devices.

10.
Carbohydr Polym ; 237: 116138, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32241433

RESUMEN

Schiff base reaction crosslinking hydrogels are advantageous by rapid formation and absence of external crosslinkers. However, poor mechanical hindered their broader applications. Here, a mechanically strengthened tissue adhesive was constructed through incorporation of chitin nano-whiskers (CtNWs) with a Schiff base crosslinking hydrogel of carboxymethyl chitosan (CMCS) and dextran dialdehyde (DDA). The optimal formulation of complexed hydrogel exhibited 1.87 folds higher compressive stress than non-complexed and 1.51 time higher adhesive strength on porcine skin. The complexed hydrogel exhibited negligible cytotoxicity, anti-swelling performance in PBS, optimum antibacterial and hemostatic capacities. In vivo implantation studies confirmed the complexed hydrogel was degradable without long-term inflammatory responses. Desirable efficacy of injectable complexed hydrogel as hemostat was demonstrated in rat liver injury model, which could avoid severe postoperative adhesion and necrosis as observed in the treatment with commercial 3 M™ vetbond™ tissue adhesive. The results highlighted that the complexed hydrogel potentiated rapid hemostasis and wound repair applications.


Asunto(s)
Materiales Biocompatibles , Hidrogeles , Adhesivos Tisulares , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/química , Quitosano/análogos & derivados , Quitosano/química , Fuerza Compresiva , Dextranos/química , Hemostáticos/síntesis química , Hemostáticos/química , Hidrogeles/síntesis química , Hidrogeles/química , Ratas , Porcinos , Adhesivos Tisulares/síntesis química , Adhesivos Tisulares/química
11.
Carbohydr Polym ; 236: 116051, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32172865

RESUMEN

Effective bleeding control is critical first step in current civilian and military trauma treatment, however commercially available hemostatic materials are difficult to achieve expected effects. In this study, a composite sponge (H-D) based on hydroxybutyl chitosan (HBC) and diatom-biosilica (DB) was designed for hemorrhage control. H-D exhibited hierarchical porous structure, favorable biocompatibility (hemolysis ratio < 5 %, no cytotoxicity), along with high and fast fluid absorbability (11-16 times than that of weight), given effective hemostasis effect (clotting time shortened by 70 % than that of control). In vitro coagulation tests demonstrated that H-D could provide strong interface effect to induce erythrocyte absorption and aggregation, as well as activating the intrinsic coagulation pathway and thus accelerated blood coagulation. These results proved that H-D composite sponge has great potential for hemorrhage control.


Asunto(s)
Materiales Biocompatibles/química , Quitosano/análogos & derivados , Diatomeas/química , Hemorragia/prevención & control , Hemostáticos/química , Dióxido de Silicio/química , Animales , Materiales Biocompatibles/toxicidad , Coagulación Sanguínea/efectos de los fármacos , Línea Celular , Quitosano/química , Quitosano/toxicidad , Equipos y Suministros , Hemólisis/efectos de los fármacos , Hemostáticos/toxicidad , Ratones , Agregación Plaquetaria/efectos de los fármacos , Porosidad , Conejos , Dióxido de Silicio/toxicidad
12.
J Mater Chem B ; 7(31): 4854-4866, 2019 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-31389952

RESUMEN

The efficient delivery of vaccines to draining lymph nodes and the induction of robust local immune responses are crucial for immunotherapy. Transdermal administration has been evidenced to facilitate the delivery of ingredients to lymph nodes. In this study, transfersomes with opposite surface charges were applied for antigen encapsulation and these were integrated with dissolving microneedles to investigate their effects on immune responses via transdermal immunization. The microneedles were easily inserted into mouse skin and achieved the local release of nanovaccines into the dermis through dissolution. Although anionic nanovaccines promoted cellular uptake via DC2.4, cationic nanovaccines exhibited stronger escape capacities from endocytic compartments, facilitating antigen processing via an MHC-I presentation pathway, and formed larger accumulations in lymph nodes. Compared with their anionic counterparts, the cationic nanovaccines more efficiently activated DC maturation and induced Th1 immunity; this was suggested by the significantly increased IgG2a/IgG1 ratio and elevated cytokine secretion from Th1 cells, without an enhancement in the Th2 response. Such an enhanced Th1 antigen-specific immune response in lymph nodes via a transdermal vaccine delivery platform is beneficial for potential immunotherapy approaches.


Asunto(s)
Inmunidad Humoral/inmunología , Ganglios Linfáticos/inmunología , Agujas , Vacunación/métodos , Vacunas/inmunología , Administración Cutánea , Animales , Células Dendríticas/inmunología , Femenino , Inmunidad Celular/inmunología , Interferón gamma/metabolismo , Interleucina-2/metabolismo , Masculino , Ratones Endogámicos BALB C , Ovalbúmina/administración & dosificación , Ovalbúmina/inmunología , Ratas Sprague-Dawley , Células TH1/inmunología , Vacunación/instrumentación , Vacunas/administración & dosificación
13.
Int J Biol Macromol ; 132: 1090-1097, 2019 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-30902715

RESUMEN

We have designed microcapsules-immobilized composite capsules and evaluated the oral delivery efficacy. The composite capsules were developed by encapsulating Perinereis aibuhitensis extract (PaE), a model substance possessing antioxidant activity, loaded gum Arabic/gelatin microcapsules in calcium alginate (CA) hydrogel (PaE:CA/GA/GE-CCs). In vitro antioxidant assay showed the obtained composite capsules were able to protect PaE from gastric acid, since O2- scavenging rate of encapsulated PaE was about 1.8 folds as that of free PaE after 5 h incubation in simulated gastrointestinal fluid. Moreover, in vivo study showed that after the treatment of oral administration for 30 days, the mice of PaE:CA/GA/GE-CCs group suffered significantly lower oxidative stress level than those of other groups, illustrated as higher SOD and catalase activity, as well as lower malondialdehyde content in liver cells. The results demonstrated the composite capsules could concentrate PaE in small intestine, and enhance the absorption efficiency and in vivo efficacy.


Asunto(s)
Alginatos/química , Antioxidantes/administración & dosificación , Antioxidantes/química , Portadores de Fármacos/química , Gelatina/química , Goma Arábiga/química , Hidrogeles/química , Administración Oral , Animales , Antioxidantes/farmacología , Cápsulas , Línea Celular , Supervivencia Celular/efectos de los fármacos , Portadores de Fármacos/toxicidad , Ensayo de Materiales , Ratones , Estrés Oxidativo/efectos de los fármacos
14.
Carbohydr Polym ; 224: 115176, 2019 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-31472871

RESUMEN

Weak mechanical properties, lack biocompatibility and relatively bioinert are formidable obstruct in application of bone repair materials. Multifunctional composite materials have been considered as a viable solution to this problem. Here, a new double network (DN) hydrogel was constructed by physical cross-linking of medical grade poly (vinyl alcohol) (PVA) and chitosan in KOH/urea dissolution system. The obtained hydrogel demonstrated excellent tensile strength (0.24 MPa), elongation at break (286%), and high compressive strength (0.11 MPa on the strain of 60%). Our studies showed that the prepared hydrogel had excellent biocompatibility in vitro and the introduction of hydroxyapatite (HAp) by surface mineralization imparted hydrogel the ability to induce rat bone marrow stem cells (rBMSCs) differentiation. The in vivo experiments revealed that the surface mineralized double network hydrogel significantly accelerated simultaneous regeneration of bone defects in a rabbit bone defect model. All the results indicated that this hydrogel has the potential as a bone repair material.


Asunto(s)
Huesos/efectos de los fármacos , Quitosano/química , Hidrogeles/química , Hidrogeles/farmacología , Minerales/química , Alcohol Polivinílico/química , Adsorción , Animales , Huesos/citología , Huesos/fisiología , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Fuerza Compresiva , Hidróxidos/química , Osteogénesis/efectos de los fármacos , Compuestos de Potasio/química , Conejos , Albúmina Sérica Bovina/química , Propiedades de Superficie , Resistencia a la Tracción , Ingeniería de Tejidos , Urea/química
15.
Int J Biol Macromol ; 121: 293-300, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30287376

RESUMEN

A thermo-sensitive hydroxybutyl chitosan (HBC) hydrogel was prepared by using 1,2­butene oxide as an etherification modifying agent. To obtain the maximum yield of HBC, response surface methodology (RSM) was applied to optimize its preparation conditions. Key factors were chosen firstly by Plackett-Burman design (PBD) experiments, such as the concentration of NaOH, the ratio of isopropanol to water and reaction temperature. Steepest ascent experiments were employed to reach the top region of the response and determine the appropriate levels of three key factors. A three-level-three-variable Box-Behnken design (BBD) was used to further optimize the synthesis parameters. The results indicated that when the concentration of NaOH and the ratio of isopropyl alcohol to water were 40.65% and 2.68:1 at reaction temperature of 59 °C, respectively, the yield of HBC production was 5.897 ±â€¯0.112 g and close to the predicted value (6.002 g), which demonstrated that the effectiveness of BBD model and the controllability for the yield of HBC in the heterogeneous reaction system.


Asunto(s)
Quitosano/análogos & derivados , Hidrogeles/química , Temperatura , Alquenos/química , Quitosano/química
16.
PLoS One ; 12(9): e0184120, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28877211

RESUMEN

Growth performance and meat quality are important traits for the pig industry and consumers. Adipose tissue is the main site at which fat storage and fatty acid synthesis occur. Therefore, we combined high-throughput transcriptomic sequencing in adipose and muscle tissues with the quantification of corresponding phenotypic features using seven Chinese indigenous pig breeds and one Western commercial breed (Yorkshire). We obtained data on 101 phenotypic traits, from which principal component analysis distinguished two groups: one associated with the Chinese breeds and one with Yorkshire. The numbers of differentially expressed genes between all Chinese breeds and Yorkshire were shown to be 673 and 1056 in adipose and muscle tissues, respectively. Functional enrichment analysis revealed that these genes are associated with biological functions and canonical pathways related to oxidoreductase activity, immune response, and metabolic process. Weighted gene coexpression network analysis found more coexpression modules significantly correlated with the measured phenotypic traits in adipose than in muscle, indicating that adipose regulates meat and carcass quality. Using the combination of differential expression, QTL information, gene significance, and module hub genes, we identified a large number of candidate genes potentially related to economically important traits in pig, which should help us improve meat production and quality.


Asunto(s)
Tejido Adiposo/metabolismo , Metabolismo de los Lípidos/fisiología , Músculo Esquelético/metabolismo , Tejido Adiposo/crecimiento & desarrollo , Animales , Perfilación de la Expresión Génica , Genes/genética , Genes/fisiología , Metabolismo de los Lípidos/genética , Músculo Esquelético/crecimiento & desarrollo , Fenotipo , Análisis de Componente Principal , Carácter Cuantitativo Heredable , Porcinos/genética , Porcinos/metabolismo , Transcriptoma/genética , Transcriptoma/fisiología
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