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1.
Knee ; 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32057638

RESUMO

BACKGROUND: The purpose of the study was to determine blood loss, transfusion risk, and incidence of immediate postoperative complications in normal, overweight, and I-II obese patients undergoing simultaneous bilateral total knee arthroplasty (SBTKA). METHOD: We identified 1070 SBTKA procedures, and separated the patients into three groups on the basis of body mass index (BMI), including normal (BMI: 18.0-24.9 kg/m2), overweight (BMI: 25.0-29.9 kg/m2), and obese groups (BMI: ≥30.0 kg/m2). The primary outcome was total blood loss and secondary outcomes were dominant and hidden blood loss, transfusion rate and volume, hemoglobin (Hb) and hematocrit drop and other complications. RESULTS: Patient's blood volume increased gradually among normal, overweight, and obese groups. There was no significant difference in blood loss or incidence of complications among the three groups, while the transfusion rate in the normal group was higher than that in overweight (36.0% vs 27.6%, p = 0.007) and obese groups (36.0% vs 24.6%, p = 0.006). In addition, the independent risk factors for complications among all groups following SBTKA included lower level of preoperative Hb (p = 0.040), general anesthesia (p = 0.002), drain use (p = 0.005), and transfusion (p < 0.001). CONCLUSIONS: I-II obesity does not increase patient's blood loss, transfusion risk, or immediate postoperative complications following SBTKA. Obese and overweight patients may have lower transfusion needs compared with normal patients because of their higher basal blood volume. The risk factors for complications after SBTKA are lower level of preoperative Hb, general anesthesia, drain use and transfusion.

2.
Int J Biol Macromol ; 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32057848

RESUMO

The functional properties and physiological functions of whey protein isolate (WPI) decreased near its isoelectric point (PI). The Maillard reaction covalently binding polysaccharides to proteins is an effective method to improve the functional activities of proteins. WPI-inulin conjugates were prepared by wet-heating method at 70 °C for 2 h, 4 h and 6 h, respectively. New bonds at higher molecular zone appearing at SDS-PAGE, decreased free amino acid content and new formed CN bonds in FT-IR of conjugates compared with WPI confirmed the formation of the covalent bonds between WPI and inulin. As the increase of the reaction time, both the brown intensity and fluorescence intensity of WPI-inulin conjugates became higher. Amino acid contents, Circular dichroism analysis and SEM analysis presented the primary structure, secondary structure and surface structure change of protein after covalent with inulin. Emulsion properties of emulsion activity (EAI) and emulsion stability (ES) of WPI-inulin conjugates were assessed and both showed significantly enhanced compared with WPI at range of pH 3 to pH 7. AAPH+ scavenging test and ORAC measurement also revealed that covalent binding with inulin enhanced the antioxidant activities of WPI. This work presented the conjugation with inulin successfully enhanced the functional properties of WPI.

3.
Food Chem ; 315: 126268, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32018083

RESUMO

Starch digestion in pulse cellular matrices is primarily determined by the hindrance of cell walls limiting enzyme diffusion as well as the retention of starch granular structure. However, the effect of hydrothermal treatment on structure and digestion properties of entrapped pulse starches is not fully elucidated. In present study, we reported the variations in structure and enzyme susceptibility of pulse cells isolated at 60 °C followed by heated at 70, 80, 90, 100 °C, which were higher than the starch gelatinization temperature. Based on the thermal and crystalline properties, entrapped starches in pulse cells were not fully gelatinized even treated at 100 °C. Whilst, the digestion of entrapped pulse starches increased with higher temperature, but still much lower than the isolated starch treated at the same temperature. In addition to physical barriers (intact cell wall) and starch structural features (partial ordered crystalline structure), the soluble/insoluble proteinaceous materials in cells also synergistically reduced the starch digestibility.

4.
J Orthop Surg Res ; 15(1): 44, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32046768

RESUMO

BACKGROUND: The induced membrane technique has achieved good clinical results in the treatment of infected bone defects, and external fixation is the main method, but it causes inconvenience and complications in patients. In this study, our objective was to investigate the outcomes of using an antibiotic cement-coated locking plate as a temporary internal fixation in the first stage of the surgical induced membrane technique for treating extremities with infected bone defects. METHODS: We retrospectively analysed patients with lower extremity infected bone defects in our department between January 2013 and December 2017. All patients were treated with the induced membrane technique. In the first stage, the defects were stabilized with an antibiotic cement-coated locking plate as a temporary fixation after debridement, and polymethyl methacrylate cement was implanted to induce the formation of a membrane. In the second stage, bone grafting rebuilt the bone defects after infection control, and the temporary fixation was changed to a stronger fixation. RESULTS: A total of 183 patients were enrolled, with an average follow-up duration of 32.0 (12-66) months. There were 154 males and 29 females with an average age of 42.8 (10-68) years. The infection sites included 81 femurs, 100 tibias and 2 fibulas. After the first stage of treatment (infection control), 16 (8.7%) patients had recurrence of infection. In terms of the incidence of complications, 4 patients had poor wound healing, 2 patients had fixation failure and 1 patient had femoral fracture due to a fall. After the second stage of treatment (bone reconstruction), there were 24 (13.1%) recurrences of infection, with a mean time of 9.9 months (range 0.5 to 36). Among them, 18 patients underwent bone grafting after re-debridement, 6 received permanent placement of antibiotic bone cement after debridement and 2 patients refused further treatment and chose amputation. Bone healing was achieved in 175 (95.9%) patients at the last follow-up, and the average time to bone union was 5.4 (4-12) months. CONCLUSIONS: Antibiotic cement-coated locking plates have good clinical effects in the control of bone infection, but attention must be paid to the possible difficulty of skin coverage when applied in calves.

5.
Nucleic Acids Res ; 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-32020194

RESUMO

Hybridization chain reaction (HCR) was a significant discovery for the development of nanoscale materials and devices. One key challenge for HCR is the vulnerability to background leakage in the absence of the initiator. Here, we systematically analyze the sources of leakage and refine leak-resistant rule by using molecular thermodynamics and dynamics, biochemical and biophysical methods. Transient melting of DNA hairpin is revealed to be the underlying cause of leakage and that this can be mitigated through careful consideration of the sequence thermodynamics. The transition threshold of the energy barrier is proposed as a testing benchmark of leak-resistance DNA hairpins. The universal design of DNA hairpins is illustrated by the analysis of hsa-miR-21-5p as biomarker when used in conjunction with surface-enhanced Raman spectroscopy. We further extend the strategy for specific signal amplification of miRNA homologs. Significantly, it possibly provides a practical route to improve the accuracy of DNA self-assembly for signal amplification, and that could facilitate the development of sensors for the sensitive detection of interest molecules in biotechnology and clinical medicine.

6.
Nanoscale ; 2020 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-32016223

RESUMO

MXenes are a new type of two-dimensional (2D) transition metal carbide or carbonitride material with a 2D structure similar to graphene. The general formula of MXenes is Mn+1XnTx, in which M is an early transition metal element, X represents carbon, nitrogen and boron, and T is a surface oxygen-containing or fluorine-containing group. These novel 2D materials possess a unique 2D layered structure, large specific surface area, good conductivity, stability, and mechanical properties. Benefitting from these properties, MXenes have received increasing attention and emerged as new substrate materials for exploration of various applications including, energy storage and conversion, photothermal treatment, drug delivery, environmental adsorption and catalytic degradation. The progress on various applications of MXene-based materials has been reviewed; while only a few of them covered environmental remediation, surface modification of MXenes has never been highlighted. In this review, we highlight recent advances and achievements in surface modification and environmental applications (such as environmental adsorption and catalytic degradation) of MXene-based materials. The current studies on the biocompatibility and toxicity of MXenes and related materials are summarized in the following sections. The challenges and future directions of the environmental applications of MXene-based materials are also discussed and highlighted.

7.
Sci Total Environ ; 711: 135189, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32000352

RESUMO

The Budyko parameter, which controls the shape of Budyko curve, represents the superimposed impact of various periodic factors (including climatic factors, catchment characteristics, large-scale climate patterns, solar activity and anthropogenic activity) on the watershed water-energy balance dynamics. However, this superimposition is not conducive to identifying the drivers of Budyko parameter dynamics at different time scales, and thus affects parameter estimation. Here we obtain the Budyko parameter ω in the Fu's equation (one form of the Budyko framework) for the Wei River Basin (WRB), and then adopt the Empirical Mode Decomposition method to reveal the relationships between factors and ω series at multiple time scales by considering the interplay among different influencing factors. Results indicate that (1) ω series are decomposed into 4-, 12-, 20-, exceeding 20-year time scale oscillations and a residual component with an significantly increasing trend in the mainstream of the WRB, a non-significantly decreasing trend in the Jing River Basin and Beiluo River Basin; (2) by analyzing the residual trend component, evaporation ratio, soil moisture and effective irrigated area are found to induce the significant increase of ω in the upstream of the WRB, whereas that in the middle and lower reaches is dominated by baseflow and Niño 3.4; (3) ω dynamics at the 4-year time scale is dominated by evaporation ratio, aridity index, baseflow and soil moisture; baseflow, Pacific Decadal Oscillation (PDO) and sunspots attribute to the dynamics at 12-year time scale; all the factors except baseflow and soil moisture contribute to the dynamics at 20- or exceeding 20-year time scales. The results of this study will help identify the connection between watershed water-energy balance dynamics and changing environment at multiple time scales, and also be beneficial for guiding water resources management and ecological development planning on the Loess Plateau.

8.
Biosci Rep ; 40(1)2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-31894841

RESUMO

Substantial researches indicated that long non-coding RNAs (lncRNAs) exerted profound effects on chemo-resistance in cancer treatment. Nonetheless, the role of NORAD in non-small-cell lung cancer (NSCLC) remains unclear. In the present study, we chose NSCLC cell lines H446 and A549 to explore the function of non-coding RNA activated damage (NORAD) in response to cisplatin (DDP) resistance of NSCLC. Experimental data manifested that NORAD was up-regulated in DDP-resistant NSCLC tissues and cells. NSCLC patients with high NORAD expression suffered a poor prognosis. NORAD knockdown resensitized H446/DDP and A549/DDP to DDP. Besides, NORAD acted as a molecular sponge of miR-129-1-3p. MiR-129-1-3p showed a low level of expression in DDP-resistant NSCLC tissues. Moreover, miR-129-1-3p overexpression impaired DDP resistance in H446/DDP and A549/DDP cells. SOX4 was the downstream target of miR-129-1-3p. Especially, SOX4 overexpression offset the effects of NORAD silence on H446/DDP and A549/DDP cells resistance to DDP. NORAD knockdown resensitized H446/DDP and A549/DDP to DDP in NSCLC via targeting miR-129-1-3p/SOX4 axis, offering a brand-new target for NSCLC chemo-resistance.

9.
Sci Total Environ ; 712: 136502, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-31931197

RESUMO

What the extent of meteorological drought could trigger the corresponding hydrological drought with different levels? This question is an important topic in the field of drought propagation, which however has not been resolved. Therefore, a novel model based on a Bayesian network was proposed to address this issue in this study. In this model, the drought pooling and excluding methods were applied to eliminate minor drought events. A drought matching approach based on drought propagation time was proposed to achieve the one by one matching between different types of drought. Moreover, based on the matched drought events and the copula-based conditional probability model, the drought propagation thresholds of meteorological drought for triggering hydrological drought at various levels were determined. In addition, the interval conditional probability was calculated to further explore the sensitivity of hydrological drought response to different meteorological drought conditions. Furthermore, the propagation ratio was proposed to characterize the differences of drought propagation threshold among various regions. The Wei River Basin was selected as a case study. Results indicated that the results of drought propagation threshold were reliable and accurate. The increase of interval conditional probability showed a typical S-curve, which can intuitively obtain the probability of hydrological drought occurrence at different levels under specific meteorological drought condition, so as to effectively guide drought preparedness and mitigation. The propagation ratio can describe the overall resistance of the basin to meteorological drought, and it mainly depended on the meteorological and underlying surface conditions as well as groundwater supply.

10.
Acupunct Med ; : acupmed2017011626, 2020 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-31948263

RESUMO

OBJECTIVES: To determine how muscle spindles are involved in the pathophysiology of chronic myofascial trigger spots (MTrSs, similar to myofascial trigger points) in a rat injury model according to the characteristics of the Hoffmann reflex (H-reflex) and the anatomical relationship between muscle spindles and MTrSs. METHODS: 16 male Sprague-Dawley rats (7 weeks old) were randomly divided into experimental and control groups. A blunt strike injury and eccentric exercise were applied to the gastrocnemius muscle of rats in the experimental group once a week for 8 weeks as a MTrS modelling intervention. Subsequently, the rats were reared normally and rested for 4 weeks. At the end of the 12th week, the rats were examined for the presence of MTrSs defined by the detection of a palpable taut band exhibiting both a local twitch response and spontaneous electrical activity. After modelling, evocation of the H-reflex and morphological examination of muscle spindles and MTrSs were conducted. RESULTS: The threshold (0.35±0.04 mA) of the H-reflex and latency (1.24±0.18 ms) of the M wave recorded at MTrSs were not significantly different to those at non-MTrSs (P>0.05). Compared with non-MTrSs, a lower Mmax (4.28±1.27 mV), higher Hmax (median (IQR) 0.95 (0.80-1.08) mV) and Hmax/Mmax (median (IQR) 0.21 (0.16-0.40)), and shorter H wave latency (4.60±0.89 ms) were recorded at MTrSs (P<0.05). Morphologically, there was a close anatomical relationship between the MTrS cells and the muscle spindles. DISCUSSION: Compared with normal muscles, the H-reflex myoelectrical activity was enhanced and some muscle spindles might have been influenced by active MTrSs. Thus, muscle spindles may play an important role in the pathological mechanism underlying myofascial trigger points.

11.
Cancer Biomark ; 2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31929143

RESUMO

BACKGROUNDS: Previous studies have showed that long non-coding RNAs (lncRNAs) are critical regulators in many cancers. The aim of this study is to investigate the clinical role and functional effects of long non-coding RNA SNHG14 in pancreatic ductal adenocarcinoma (PDAC). METHODS: The expression of SNHG14 in 58 pairs of pancreatic cancer tissues and adjacent normal tissues was detected by quantitative real-time PCR (qRT-PCR) analysis. The correlations between SNHG14 expression and PDAC patients' clinicopathological characteristics and prognosis were statistically assessed. Cell counting kit-8 (CCK8) and transwell cell invasion assays were employed to detect the capacities of cell proliferation and cell invasion. The western blot analysis was used to detected the expression of E-cadherin and Vimentin. RESULTS: In the study, we found that SNHG14 expression was higher in PDAC tissue compared to adjacent normal tissues by qRT-PCR analysis. Higher SNHG14 expression was significantly associated with advanced TNM stage and positive lymph node metastasis in PDAC patients. Furthermore, we demonstrated that higher SNHG14 expression acted as a poor predictor in PDAC patients compared with lower SNHG14 expression. Moreover, we showed that higher SNHG14 expression promoted cell proliferation, cell colony formation and cell invasion ability in PDAC. Upregulation of SNHG14 expression promoted cell invasion by affecting E-cadherin expression via interacting with EZH2. CONCLUSIONS: Thus, these results indicated that SNHG14 expression acts as a prognostic maker for PDAC and potential target of PDAC treatment.

12.
J Agric Food Chem ; 68(4): 1091-1100, 2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-31896257

RESUMO

The physical structure of type 1 resistant starch (RS 1) could influence the metabolite production and stimulate the growth of specific bacteria in the human colon. In the present study, we isolated intact cotyledon cells from pinto bean seeds as whole pulse food and RS 1 model and obtained a series of cell wall integrities through controlled enzymolysis. In vitro human fecal fermentation performance and microbiota responses were tested, and we reported that the cell wall integrity controls the in vitro fecal fermentation rate of heat-treated pinto bean cells. The concentration of butyrate produced by pinto bean cell fermentation enhanced with weakened cell wall integrity, and certain beneficial bacterial groups such as Blautia and Roseburia genera were remarkably promoted by pinto bean cells with damaged cell wall integrity. However, the intact cell sample had a shape more similar to microbiota composition with the purified cell wall polysaccharides, rather than the damaged cells.

13.
Artif Cells Nanomed Biotechnol ; 48(1): 435-442, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31916466

RESUMO

Non-coding RNAs play an important role in the pathogenesis of prostate cancer (PC). This study aims to characterize the role of GAS5 rs145204276 and HOTAIR rs4759314 polymorphisms in the pathogenesis of PC. Both INS allele of GAS5 rs145204276 and A allele of HOTAIR rs4759314 were identified to increase the survival of PC patients. And patients carrying DEL/DEL + AG genotypes tend to present higher levels of HMGB1, GAS5, HOTAIR and lower levels of miR-1284 and miR-22. In addition, the transcription activity of GAS5 promoter was increased by the deletion allele of rs145204276 polymorphism, while the G allele of rs4759314 polymorphism increased the transcription activity of HOTAIR promoter. GAS5 and HOTAIR could bind to miR-1284 and miR-22, respectively, while miR-1284 and miR-22 could bind to the 3'UTR of HMGB1. Compared with the control group, the expressions of miR-1284 or miR-22 were decreased with the presence of GAS5 or HOTAIR, and the expression of HMGB1 was the highest in the GAS5 + HOTAIR group. In summary, the findings of this study demonstrated that both GAS5 rs145204276 and HOTAIR rs4759314 polymorphisms could affect the prognosis of PC by modulating the expression of HMGB1 via modulating the GAS5/miR-1284/HMGB1 and HOTAIR/miR-22/HMGB1 signalling pathways.

14.
J Agric Food Chem ; 68(1): 147-159, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31826616

RESUMO

This study was aimed at investigating the hypoglycemic and hypolipidemic effects of a polysaccharide (RTFP) isolated from Rosa roxburghii Tratt fruit on type-2 diabetic db/db mice. The results indicated that the oral administration of RTFP could significantly decrease the body weight, fat, and liver hypertrophy and the levels of fasting blood glucose, serum insulin, and serum lipids of the db/db mice. Histopathological observation showed that RTFP could effectively protect the pancreas, liver, and epididymal fat against damage and dysfunction. Real-time quantitative polymerase chain reaction analysis confirmed that the gene expression levels of peroxisome proliferator-activated receptors-γ (PPAR-γ), sterol regulatory element-binding protein-1 (SREBP-1c), acetyl-CoA carboxylase-1 (ACC-1), fatty acid synthase (FAS), and glucose-6-phosphatase (G6 Pase) were significantly down-regulated in the liver of db/db mice after treatment with RTFP. Moreover, RTFP treatment reversed gut dysbiosis by lowering the Firmicutes-to-Bacteroidetes ratio and enhancing the relative abundances of beneficial bacteria including Bacteroidaceae, Bacteroidaceae S24-7 group, and Lactobacillaceae. These findings suggest that RTFP can be used as a promising functional supplement for the prevention and treatment of type-2 diabetes mellitus.


Assuntos
Colo/microbiologia , Hiperglicemia/tratamento farmacológico , Hiperlipidemias/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Hipolipemiantes/administração & dosagem , Extratos Vegetais/administração & dosagem , Polissacarídeos/administração & dosagem , Rosa/química , Animais , Colo/metabolismo , Modelos Animais de Doenças , Frutas/química , Microbioma Gastrointestinal , Humanos , Hiperglicemia/metabolismo , Hiperglicemia/microbiologia , Hiperlipidemias/metabolismo , Hiperlipidemias/microbiologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Camundongos , Triglicerídeos/metabolismo
15.
Arch Environ Contam Toxicol ; 78(1): 117-123, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642948

RESUMO

As a commonly used pyrethroid insecticide, deltamethrin is very toxic to honeybees, which seriously threatens the managed and feral honeybee population. Because deltamethrin is a nerve agent, it may interfere with the nervous system of honeybees, such as dance behavior and memory-related characteristics. We found that the waggle dances were less precise in honeybees that consumed syrup containing deltamethrin (pesticide group) than those that consumed normal sucrose syrup (control group). Compared with the control group, honeybees of the pesticide group significantly increased number of circuits per 15 s, the divergence angle, return phases in waggle dances, as well as the crop content of the dance followers. Furthermore, six learning and memory-related genes were significantly interfered with the gene expression levels. Our data suggest that the sublethal dose of deltamethrin impaired the honeybees' learning and memory and resulted in cognitive disorder. The novel results assist in establishing guidelines for the risk assessment of pesticide to honeybee safety and prevention of nontarget biological agriculture pesticide poisoning.

16.
Angew Chem Int Ed Engl ; 59(4): 1619-1626, 2020 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-31710148

RESUMO

Carbon nanotubes (CNTs) have unusual physical properties that are valuable for nanotechnology and electronics, but the chemical synthesis of chirality- and diameter-specific CNTs and π-conjugated CNT segments is still a great challenge. Reported here are the selective syntheses, isolations, characterizations, and photophysical properties of two novel chiral conjugated macrocycles ([4]cyclo-2,6-anthracene; [4]CAn2,6 ), as (-)/(+)-(12,4) carbon nanotube segments. These conjugated macrocyclic molecules were obtained using a bottom-up assembly approach and subsequent reductive elimination reaction. The hoop-shaped molecules can be directly viewed by a STM technique. In addition, chiral enantiomers with (-)/(+) helicity of the [4]CAn2,6 were successfully isolated by HPLC. The new tubular CNT segments exhibit large absorption and photoluminescence redshifts compared to the monomer unit. The carbon enantiomers are also observed to show strong circularly polarized luminescence (glum ≈0.1). The results reported here expand the scope of materials design for bottom-up synthesis of chiral macrocycles and enrich existing knowledge of their optoelectronic properties.

17.
Crit Rev Food Sci Nutr ; 60(4): 695-708, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30638035

RESUMO

The objective of this review is to summarize knowledge on the inhibitory effects (IEs) of flavonoids on α-amylase (αA) and α-glucosidase (αG) relevant to the search of substitutes of acarbose (Aca). Flavonoids reported to be more effective at inhibiting αG than Aca have been summarized. The concept of "relative coefficient to Aca (RCAca)" has been proposed to integrate data from various reports. Correlations between hydrogen bond donors (H-donors), hydrogen bond acceptors (H-acceptors), partition coefficient values (XLog P3), and RCAca are discussed. Two kinds of binding modes between flavonoids and enzymes have been observed: (i) flavonoids directly bind to amino acid residues (AARs) in the active sites of enzymes and exclude the binding of substrate; (ii) flavonoids interact with AARs near the active site and close the channel to the active center. Some groups are correlated with stronger IEs: (i) substitutions of caffeoyl, galloyl, and prenyl groups in flavonoids enhance IEs; (ii) steric hindrance attenuates IEs, and linear molecules tend to be stronger inhibitors of porcine pancreatic αA (PPA). Whilst many achievements have been made, our understanding of the combined effects of different flavonoids, and flavonoids and Aca, remain ambiguous, and the effects of food matrices and stomach digestion on IEs of flavonoids are poorly understood. This review provides a comprehensive understanding on the use of flavonoids as αA and αG inhibitors for controlling diabetes.

18.
Ecotoxicol Environ Saf ; 188: 109889, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31704331

RESUMO

It is known that abamectin (ABM) inflicts oxidative damage on aquatic animals; however, knowledge about the immune response under pesticide-induced oxidative stress is incomplete. In the present study, several cellular and humoral immune parameters, including total haemocyte counts (THC), lysosomal membrane stability (LMS), activities of acid phosphatase (ACP), alkaline phosphatase (AKP) and lysozyme (LZM) were investigated to reveal the effects of ABM exposure on the immune defence mechanisms of the important freshwater crab, Erocheir sinensis. According to the results, a significant increase of THC was found in low concentration groups (0.03 and 0.06 mg/L), while dramatic decreases occurred in high concentration groups (0.12 and 0.24 mg/L) after 96 h of exposure. We also detected significant increases of reactive oxygen species (ROS) in haemocytes at 0.12 and 0.24 mg/L, and there was a dose- and time-dependent decrease of lysosomal membrane stability. These results suggest that the excessive generation of ROS induced by ABM may be leading the massive collapse of lysosomal membrane, which in turn may be causing the sharp drop of haemocyte counts in E. sinensis. The increase of hydrolytic enzymes ACP and AKP at low concentrations and the decrease at high concentrations also indicate an immune response associated with haemocytes status under stress. However, activities of LZM decreased significantly. After injection of Aeromonas hydrophil, mortalities increased under exposure to ABM and were positively related to ABM concentration. These results confirm that ABM exposure has the ability to impair immune defence and result in the host's susceptibility to pathogens.


Assuntos
Braquiúros/imunologia , Inseticidas/toxicidade , Ivermectina/análogos & derivados , Estresse Oxidativo/efeitos dos fármacos , Poluentes Químicos da Água/toxicidade , Animais , Braquiúros/efeitos dos fármacos , Braquiúros/metabolismo , Hemócitos/efeitos dos fármacos , Hemócitos/metabolismo , Hemócitos/patologia , Imunidade Inata/efeitos dos fármacos , Ivermectina/toxicidade , Lisossomos/efeitos dos fármacos , Lisossomos/metabolismo , Espécies Reativas de Oxigênio/metabolismo
19.
Food Chem ; 305: 125476, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31525589

RESUMO

Octenylsuccinate quinoa starch (OSQS) granule that stabilized Pickering emulsion gel with different gel networks by modulating the oil volume fraction (Φ) was developed as a carrier for lutein. Pickering emulsion gels stabilized by OSQS were achieved at Φ values ranging from 30% to 60%. Increasing Φ progressively increased the droplet size, storage modulus, and apparent viscosity, resulting in the formation of gel-like structure. Confocal laser scanning microscopy showed that OSQS formed a densely packed layer at the oil/water interface, the degree of aggregation between droplets increased, and the gel network enhanced through droplet flocculation with increasing Φ. After 31 days of storage, the retention index of lutein in the emulsion gel could reach 55.38%, and the corresponding half-life times increased from 12 to 41 days. This study will be useful for designing starch-based Pickering emulsion gel with tunable gel network and desirable characteristics as delivery carrier of sensitive bioactive compounds.


Assuntos
Chenopodium quinoa/metabolismo , Géis/química , Luteína/química , Amido/química , Succinatos/química , Emulsões/química , Meia-Vida , Luteína/metabolismo , Microscopia Confocal , Tamanho da Partícula , Reologia
20.
Mater Sci Eng C Mater Biol Appl ; 106: 110157, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753361

RESUMO

Surface modification of carbon nanotubes (CNTs) through controlled living polymerization has demonstrated to be a useful route for preparation of CNTs based polymer composites. However, surface oxidation of CNTs is often required to generate functional groups, which can be further utilized for immobilization of polymerization initiator and grafting polymers. The surface oxidation procedure is rather complex, high energy cost, low efficient and will destroy the structure of CNTs. Therefore, the development of simple and efficient strategies for preparation of CNTs based composites should be of great research interest and raised much attention recently. In this work, a novel mussel inspired strategy that combination of ATRP and ring-opening reaction has been developed for simultaneous preparation of glycosylated and PEGylated CNTs for the first time. CNTs were first coated with polydopamine (PDA) through self-polymerization of dopamine under alkaline aqueous solution. Then polymerization initiator was immobilized on CNT-PDA through simple esterification and amidation reaction to obtain CNT-PDA-Br. The PEGylated CNTs were synthesized through ATRP using CNT-PDA-Br as initiator and polyethylene glycol monoester acrylate and itaconic anhydride (IA) as the monomers. Finally, glucosamine was conjugated with IA via ring-opening reaction. The successful preparation of glycosylated and PEGylated CNTs (CNT-PDA-Poly(PEGMA-co-IA)-Glu) was confirmed by a number of characterization techniques in details. The obtained CNTs based composites showed improved aqueous dispersibility and desirable cytocompatibility, implying their biomedical application potential. As compared with the conventional covalent strategies, the mussel inspired method described in this work will not destroy the structure for introduction functional groups on the surface of CNTs, that can occur under rather mild experimental conditions, including room temperature, short reaction time and aqueous solution. On the other hand, the mussel inspired chemistry can also be used for surface modification of almost any materials regardless of their size, morphology and compositions. Therefore, we believe that the mussel inspired strategy should be a general method for fabrication of various polymer composites for different applications.

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