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1.
ACS Omega ; 7(12): 10622-10626, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35382316

RESUMO

An organic photodetector prepared by a simple solution method based on renewable citrus pectin with an optimized concentration of aluminum nitrate (AlC05) is introduced herein. The effects of different concentrations of aluminum nitrate on the morphology and optical properties were investigated through various characterization methods. An AlC concentration of 0.5 mg/mL was found to provide the highest on/off ratio and acceptable rise and decay times. Also, the optimized device (Al/AlC0.5/ITO) exhibited good stability and repeatability at a 0.1 V bias under 440 nm visible light. Based on these results, citrus pectin materials were successfully used to fabricate an organic photodetector with a simple and cost-efficient fabrication process, while taking into account environmental commitments.

2.
ACS Appl Mater Interfaces ; 14(4): 5959-5972, 2022 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-35049269

RESUMO

Gamma radiolysis behaviors and mechanisms of silica-filled o-cresol formaldehyde epoxy are studied at 2.20 × 10-5 to 1.95 × 10-1 Gy/s. The radiolysis-induced changes in chemical structures do not severely affect its thermostability. The slightly deteriorated mechanical strength at temperature exceeding 100 °C is accompanied by the declining glass transition temperature (from 185.9 to 172.2 °C) and enhanced damping ability. The gas yields of hydrogen, methane, and carbon dioxide manifest a remarkable dose rate effect. Based on the Schwarzschild law, their yields at an extremely low dose rate are accurately predicted by the established master curves. Besides, the latent radiolysis of gas products and postradiation effect are found with caution. The radiation-caused residual spin species are proved to be composed of silica defects and a phenoxy-type free radical with a tert-butyl group, according to the experimental results, theoretical calculations, and spectra simulations. The lower vertical ionization potential (7.6 eV) and adiabatic ionization potential (7.1 eV) are primarily due to the ionization of the benzene ring moiety with the tert-butyl group, which is likely to suffer from radiolysis. The calculated bond dissociation energy (260.8-563.5 kJ/mol) of the typical chemical bonds of epoxy is consistent with its radiolytic vulnerability and degradation mechanisms.

3.
Environ Res ; 209: 112732, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35077715

RESUMO

Decomposing cyanobacterial bloom-induced black blooms been seen as an issue in the management of freshwater ecosystems, but its effect on sulfate-reducing bacteria (SRB) in shallow freshwater lakes is not clear. The objective of this study is to present an in-depth investigation of black bloom effects on the activities and composition of SRB, as well as the interactions between SRB and other bacteria. Water and surface sediments samples were collected from a shallow freshwater lake during black and non-black blooms. Sulfate reduction rates (SRRs) in the water column were determined from the linear regression of sulfate depletion with time. Quantitative real-time polymerase chain reactions (qPCRs), targeting the dsrA gene and Illumina sequencing of 16S rDNA, were used to estimate the SRB population and SRB community structures, respectively. Our data indicate that although a higher abundance of SRB was responsible for the higher SRR in the bottom water (34.09 ±â€¯2.37 nmol mL-1 day-1) than in the surface water (14.57 ±â€¯2.91 nmol mL-1 day-1) during black blooms, cell-specific sulfate reduction rates (csSRRs) in the distinct water layers were not significantly different (P = 0.95), with the value of approximately 0.017 fmol cell-1 day-1. Additionally, Desulfomicrobium and Desulfovibrio were the two main genera of SRB in the water column during black bloom season, while Desulfobulbus, Desulfobacca and Desulfatiglans genera were identified in the sediments of both the black and non-black blooms in genera pools. Each SRB genus preferentially associated with bacteria for specific functions in the bacterial co-occurrence network, regardless of whether black booms occurred or not. These results extend our knowledge on the importance of SRB during black blooms and the adaptation of SRB to environmental changes in freshwater lakes.


Assuntos
Cianobactérias , Lagos , Ecossistema , Eutrofização , Lagos/química , Sulfatos
4.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 38(5): 443-447, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-37088749

RESUMO

OBJECTIVE: To investigate the effects of ZnO nanoparticles (ZnO NPs) on proliferation and apoptosis of human lung epithelial cells BEAS-2B and its molecular mechanisms. METHODS: BEAS-2B cells were treated with ZnO NPs at concentrations of 3, 6 and 12 µg/ml for 12 h and 24 h, the control group was not treated with ZnO NPs, each with 3 replicate wells. Cell viability was detected by CCK-8 method, and the half lethal concentration (IC50) was analyzed. Then, the BEAS-2B cells were treated with ZnO NPs at selected concentrations of 3 and 6 µg/ml for 24 h respectively,each group was set with 3 replicate. Cell morphology was observed under inverted microscope. The morphology of cell nuclei was observed by Hochest33342 staining. The morphology of apoptosis was observed by AO staining and scanning electron microscopy. Cell cycle progression, cell apoptosis rate and the level of reactive oxygen species(ROS)were detected by flow cytometry. Western blot was used to detect the expression levels of Bcl-2 and Bax protein. RESULTS: Compared with the control group, the cell viability of cells treated with ZnO NPs were decreased significantly(P<0.01), and the IC50 was 6.13 µg/ml at 24 h of drug treatment. After the cells were treated with ZnO NPs for 24 h, the levels of ROS were increased significantly(P<0.05, P<0.01)in 3 µg/ml, 6 µg/ml groups. The cell cycle was arrested at G2/M phase, chromatin condensation and apoptotic bodies were induced, apoptosis rate was increased significantly(P<0.01) in 6 µg/ml group. The expression of Bcl-2 was decreased(P<0.05), and the expression of Bax was increased (P<0.05) in cells treated with 6 µg/ml ZnO NPs for 24 h. CONCLUSION: ZnO NPs induced ROS accumulation, blocked progress of cell cycle and induced cell apoptosis in BEAS-2B cells.


Assuntos
Óxido de Zinco , Humanos , Óxido de Zinco/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Apoptose , Células Epiteliais , Proteínas Proto-Oncogênicas c-bcl-2 , Pulmão/metabolismo , Proliferação de Células
5.
Zhonghua Nan Ke Xue ; 28(4): 307-313, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37477451

RESUMO

OBJECTIVE: To observe the clinical effects of pre-suture ligation and suture knot positioning in single-operator circumcision with the stapler. METHODS: Totally 120 six to fourteen years old children with phimosis or redundant prepuce were equally and randomly assigned to receive traditional single-operator circumcision with the stapler (group 1), single-operator circumcision with double suture knots for positioning the cutting plane with the stapler (group 2), or pre-suture ligation plus single-operator suture knot positioning circumcision with the stapler (group 3). We recorded and comparatively analyzed the operation time, intraoperative blood loss and hematoma, the number of residual suture knots, the patients' satisfaction with foreskin reservation, sutured frenulum and incision aesthetics, and the rates of surgical conversion, severe postoperative dysuria, severe wound exudation and perioperative anxiety of the parents and surgeon. RESULTS: Statistically significant differences were observed among the three groups in the operation time, intraoperative blood loss, incidence of intraoperative hematoma, number of residual suture knots, the patients' satisfaction with foreskin reservation, sutured frenulum and incision aesthetics, and the rates of surgical conversion, severe postoperative dysuria, severe wound exudation and perioperative anxiety of the parents and surgeon (P < 0.05). Compared with group 1, group 3 showed obviously less operation time and intraoperative blood loss and lower incidence of intraoperative hematoma, number of residual suture knots and rates of surgical conversion and perioperative anxiety of the parents and surgeons, and higher rates of patients' satisfaction with foreskin reservation, sutured frenulum and incision aesthetics. The intraoperative blood loss, incidence of intraoperative hematoma, and the rates of severe postoperative dysuria, severe wound exudation and perioperative anxiety of the parents and surgeon were lower in group 3 than in group 2. CONCLUSION: Pre-suture ligation plus single-operator suture knot positioning circumcision with the stapler helps reduce the operation time, intraoperative blood loss, incidence of intraoperative hematoma, number of residual suture knots and rates of surgical conversion and perioperative anxiety of the parents and surgeon, and increase the patients' satisfaction with foreskin reservation, sutured frenulum and incision aesthetics.

6.
Zhonghua Nan Ke Xue ; 27(4): 324-329, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-34914215

RESUMO

OBJECTIVE: To observe the clinical effect of single-suture versus that of double-suture knot in positioning the cutting plane in circumcision with a stapler. METHODS: We randomly assigned 120 patients with redundant prepuce or phimosis into three groups of an equal number to receive traditional circumcision without suture knot (group 1), circumcision with single-suture knot (group 2), and circumcision with double-suture knot (group 3) for positioning of the cutting plane. We recorded and compared the operation time, intraoperative blood loss, the rates of frenulum sewing, non-frenulum sewing, poor frenulum sewing and surgical conversion, intraoperative anxiety of the doctors, postoperative ecchymosis, and satisfaction with the retained ventral and dorsal prepuce and postoperative penile appearance among the three groups. RESULTS: There were statistically significant differences among the three groups in the surgery time, intraoperative blood loss, the rates of frenulum sewing, non-frenulum sewing, poor frenulum sewing and surgical conversion, intraoperative anxiety of the doctors, and satisfaction with the retained ventral and dorsal prepuce and postoperative penile appearance, (P < 0.05), but not in postoperative ecchymosis (P = 0.849). The rate of satisfaction with the retained dorsal prepuce was remarkably higher in group 3 than in group 2 (P = 0.003), and the intraoperative anxiety rate of the doctors was lower in the former than in the latter group (P = 0.003). CONCLUSIONS: Both single- and double-suture knots for positioning the cutting plane in circumcision with a stapler can help reduce the operation time, intraoperative blood loss, the rates of frenulum sewing, non-frenulum sewing, poor frenulum sewing and surgical conversion, intraoperative anxiety of the doctors, and satisfaction with the retained ventral and dorsal prepuce and postoperative penile appearance, and double-suture knot positioning has an even higher application value in decreasing the intraoperative anxiety of the doctors and increasing the satisfaction with the retained dorsal prepuce.


Assuntos
Circuncisão Masculina , Fimose , Prepúcio do Pênis , Humanos , Masculino , Fimose/cirurgia , Período Pós-Operatório , Suturas
7.
Zhonghua Nan Ke Xue ; 27(7): 621-625, 2021 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-34914229

RESUMO

OBJECTIVE: To investigate the efficiency and complications of modified urethral reconstruction with lingual mucosa in the treatment of complicated anterior urethral stricture (CAUS). METHODS: We retrospectively studied the clinical data on 10 cases of CAUS treated by modified urethral reconstruction with lingual mucosa from December 2017 to June 2019 concerning the age of the patients and the causes, location and length of urethral stricture. We statistically analyzed the pre- and post-operative maximum urine flow rate (Qmax), scores on Mental Status Scale in Non-psychiatric Settings (MSSNS) and quality of life (QOL) scores and observed post-operative complications such as abnormal taste, tongue numbness, urinary tract infection, urethral diverticulum, and urethral stricture. RESULTS: Compared with the baseline, Qmax was significantly improved and the MSSNS and QOL scores dramatically decreased at 3, 6 and 12 months after surgery (P < 0.01). Paraurethral infection developed in 1 case postoperatively, which was cured after dressing change, external urethral orifice stenosis occurred in another, which was improved after regular urethral orifice expansion, and mild tongue numbness was found in 2 cases at 1 month but gradually restored to abnormal. Urethrography showed no urethral diverticulum before catheter removal. CONCLUSIONS: Lingual mucosa is an ideal alternative material for urethral reconstruction in the treatment of CAUS, and lateral lingual mucosa can be easily obtained. Modified urethral reconstruction by embedding lingual mucosa in the dorsal base of the urethra, with the advantages of definite effectiveness and few postoperative complications, is worthy of clinical application.


Assuntos
Estreitamento Uretral , Humanos , Masculino , Mucosa , Qualidade de Vida , Estudos Retrospectivos , Língua , Uretra , Estreitamento Uretral/etiologia , Estreitamento Uretral/cirurgia
8.
Zhonghua Nan Ke Xue ; 27(3): 226-230, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-34914304

RESUMO

OBJECTIVE: To observe the clinical effect of prostatic artery embolization (PAE) in the treatment of high-risk patients with BPH. METHODS: Nine high-risk patients with BPH underwent PAE in the Third Affiliated Hospital of Anhui Medical University from January 2016 to June 2018. We followed up the patients and obtained their IPSS, quality of life score (QOL), postvoid residual urine volume (PVR), maximum urinary flow rate (Qmax), prostate volume (PV), hours of undisturbed sleep (HUS), Self-Rating Anxiety Scale score (SAS) and incidence of postoperative complications before and at 6, 12 and 24 months or longer after surgery, followed by comparative analysis of the parameters. RESULTS: Compared with baseline, IPSS, QOL, PVR, Qmax, PV, HUS and SAS were all significantly improved in the patients at 6, 12 and ≥24 months after PAE (P < 0.05). Only 1 case complained of mild numbness in the buttocks, which was gradually relieved after acupuncture therapy. CONCLUSIONS: Prostatic artery embolization is definitely effective for the treatment of high-risk patients with BPH with the bladder volume ≥200 ml, with few postoperative complications, and can be used as an effective therapeutic supplementary for improving the urination symptoms of the patients.


Assuntos
Embolização Terapêutica , Hiperplasia Prostática , Artérias , Humanos , Masculino , Próstata/cirurgia , Hiperplasia Prostática/terapia , Qualidade de Vida
9.
ACS Appl Mater Interfaces ; 13(34): 41287-41302, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34410100

RESUMO

The γ radiolysis behavior of polydimethylsiloxane (PDMS) in the radiation-thermal environments (dose rate, 0.2 Gy/s) is studied to pinpoint the basic knowledge of the temperature (20-70 °C) effects. The non-monotonous temperature effects on the formation of gas products, paramagnetic species in silica, and cross-linking density are proposed to correlate with the complex chemical reaction mechanisms. Besides, molecular dynamics simulation and theoretical calculation are first performed simultaneously based on the radical chemistry and intricate material composition, making it easier to comprehend and further harness the radiolysis mechanisms and structure deterioration of PDMS. The γ radiation-induced primary gas products and dominant cross-linking phenomena are reproduced by the molecular dynamics simulations with a reactive force field, and the reaction mechanisms and physicochemical interactions among PDMS chains, gas products, reactive radicals, and silica fillers are thoroughly studied at the atomic scale. The thermochemistry of the barrierless radical coupling reactions and reactions with explicit high-barrier transition states is calculated at the M06-2X theoretical level with the 6-311g(d, p) basis set. The barrierless reactions are all exothermal with the heat release of 321-618 kJ/mol, while the potential barriers for reactions with explicit transition states vary between 37 and 229 kJ/mol. The results show that γ radiation-induced radicals are crucial for the ensuing gas formation and cross-linking reactions, especially for the radical coupling reactions. The radical chemistry involved in the radiolytic PDMS is the key to understand and simulate its radiolysis behavior, according to the experimental and simulated results.

10.
BMC Cardiovasc Disord ; 20(1): 124, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32156261

RESUMO

BACKGROUND: Heparin-binding protein (HBP), a potent inducer of increased vascular permeability, is a potentially useful biomarker for predicting outcomes in patients with postoperative myocardial injury-related cardiogenic shock (MIRCS). We aimed to evaluate and validate HBP as a prognostic biomarker for postoperative MIRCS. METHODS: We performed a case-control study in 792 patients undergoing cardiac surgery from January 1, 2016, to August 1, 2019, including 172 patients with postoperative MIRCS and 620 age- and sex-matched controls. The association between HBP and MIRCS was determined by multivariate logistic regression analysis. Receiver operating characteristic curves (ROCs) with area under the curve (AUC) were performed to calculate the cut-off value, sensitivity and specificity. The association between HBP and cardiac troponin T (cTnT) was determined by multivariable linear regression analysis. Blood samples were drawn from the coronary sinus and arterial line of the cardiopulmonary bypass (CPB) before aortic cross-clamping (time point 1) and 5 min after aortic declamping (time point 2). RESULTS: Before aortic cross-clamping, coronary sinus HBP (HBPCS1) showed no differences between the two groups. However, after declamping, the MIRCS group had a significantly higher sinus HBP level (HBPCS2) than did the control group. HBPCS2 predicted MIRCS with an AUC of 0.85 (95% CI: 0.81-0.89, cut-off: 220 ng/ml, sensitivity: 92% and specificity: 70%). After adjusting for confounding factors, we found that HBP was an independent risk factor for MIRCS (OR: 7.65, 95% CI: 4.86-12.06, P < 0.01) and was positively associated with cTnT (ß > 0, P < 0.01). CONCLUSIONS: Elevated levels of coronary sinus HBP were useful biomarkers for predicting MIRCS after cardiac surgery.


Assuntos
Peptídeos Catiônicos Antimicrobianos/sangue , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Choque Cardiogênico/etiologia , Idoso , Biomarcadores/sangue , Proteínas Sanguíneas , Procedimentos Cirúrgicos Cardíacos/mortalidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , Choque Cardiogênico/sangue , Choque Cardiogênico/diagnóstico , Choque Cardiogênico/mortalidade , Fatores de Tempo , Troponina T/sangue , Regulação para Cima
11.
J Nanosci Nanotechnol ; 20(3): 1756-1764, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31492340

RESUMO

Organic-inorganic CoFe2O4/polyaniline (CoFe2O4/PA) nanocomposites with embedded structures were synthesized by combining the sol-gel auto-combustion process and in-situ oxidative polymerization. The phases and morphologies of the prepared samples were identified. The pure CoFe2O4 samples exhibited inferior microwave-absorption properties in a frequency range of 2-18 GHz. Upon the incorporation of PA, the formed CoFe2O4/PA nanocomposites exhibited rather good absorption performances. When the sample thickness was 2.5 mm, the maximum reflection loss (RL) reached -22.3 dB, while the RL below -10 dB corresponded to the range of 11.0-17.1 GHz, which contains almost the entire Ku-band, making the structure promising for commercial and military applications. A physical model was employed to explain the effects of the embedded structure on the microwave-absorption performances. The excellent microwave-absorption performances could be attributed to the interfacial polarization and repeated reflection of the microwaves inside the CoFe2O4/PA composite.

12.
Arch Med Sci ; 15(3): 765-773, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31110544

RESUMO

INTRODUCTION: The purpose of the present study was to evaluate the antiproliferative activity of dehydrocostus lactone against human BON-1 cancer cell lines and to explore the possible underlying mechanism. MATERIAL AND METHODS: MTT cell viability assay was used to determine cytotoxic effects of dehydrocostus lactone in BON-1 cells. Fluorescence and transmission electron microscopic (TEM) techniques were used to study the effect of the compound on cellular morphology and apoptosis. Flow cytometry was used to assess the effect on cell cycle phase distribution. Effects of the drug on cell apoptosis and mitochondrial membrane potential were analyzed by flow cytometry using annexin v and rhodamine-123 as fluorescent probes. RESULTS: The results of the present study indicated that dehydrocostus lactone significantly (p < 0.01) inhibited the growth of BON-1 cancer cells. These growth inhibitory effects of dehydrocostus lactone on BON-1 were found to be time and concentration-dependent. The IC50 of dehydrocostus lactone were found to be 71.9 µM and 52.3 µM at 24 and 48 h time intervals respectively. The growth inhibitory effects of dehydrocostus lactone were found to be due to loss of mitochondrial membrane potential, the induction of apoptosis and sub-G1 cell cycle arrest. CONCLUSIONS: Dehydrocostus inhibits in vitro gastrinoma cancer cell growth and therefore may prove beneficial in the management of gastrinoma cancer.

13.
Kaohsiung J Med Sci ; 35(2): 95-101, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30848029

RESUMO

Cathepsin S plays an important role in the pathogenesis of several cardiovascular diseases; however, the relationship between serum cathepsin S and cerebral infarction (CI) is still unknown. This study aimed to investigate the relationship between acute phase serum cathepsin S level and cerebral infarction. A total of 202 stroke patients were enrolled into this study, and were divided into cerebral infarction (n = 140) group and non-cerebral infarction group (non-CI, n = 62). Fifty healthy individuals were recruited as the control group. Serum levels of cathepsin S and cystatin C were measured at days 1, 7, and 14 posthospitalization. Compared to the non-CI group, the CI group had significantly higher rates of hypertension, dyslipidemia, and smoking (all P < 0.05). The CI group had significantly higher cathepsin S levels and cathepsin S to cystatin C ratio (CatS/CysC) at both days 1 and 7 posthospitalization (both P < 0.05). Multivariate logistic regression analysis demonstrated that cathepsin S level (day 7) and CatS/CysC (days 1 and 7) were the associated factors with CI (all P < 0.05). Receiver operating characteristic (ROC) curve analysis revealed that the Area Under Curve (AUC) value of CatS-day7, CatS/CysC-day1, and CatS/CysC-day7 were 0.726 (95% CI: 0.652-0.800, P < 0.001), 0.641 (95% CI: 0.559-0.723, P = 0.001), and 0.721 (95% CI: 0.645-0.797, P = 0.039), respectively. Cathepsin S and CatS/CysC were associated with acute CI, and may have the potential to be the diagnostic biomarkers for CI. Our findings help to better understand the role of serum cathepsin S level in CI.


Assuntos
Proteínas de Fase Aguda/metabolismo , Catepsinas/sangue , Infarto Cerebral/sangue , Cistatina C/sangue , Idoso , Infarto Cerebral/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC
15.
Carbohydr Polym ; 206: 609-615, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30553364

RESUMO

Self-cross-linked aerogel based on pectin and melamine-formaldehyde resin (MF) was fabricated via freeze-drying method using water as solvent, where pectin is structural material meanwhile acting as acid to catalyse the cross-linking of MF. The cross-linking reaction easily occurs without additional additives, which can be significantly accelerated at elevated temperatures, with a critical value of about 55 °C. The obtained aerogel shows network microstructures as observed with SEM. With increasing pectin content, the aerogel shows significantly increased compressive modulus. The compressive modulus of M10Pe5 arrives 23.2 MPa, the specific modulus of which arrives 188 MPa cm3/g, while pure MF aerogel are too fragile to keep intact after freeze-dried. The resulting aerogel has good thermal stability, excellent water resistance (can be second dried with limited strength loss) and low flammability. This partially bio-based novel aerogel with impressive properties is promising in many applications.

16.
Pestic Biochem Physiol ; 148: 159-165, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29891367

RESUMO

Low levels of endosulfan are known to stimulate mast cells to release allergic mediators, while imidacloprid can inhibit IgE-mediated mast cell degranulation. However, little information about the effects of both pesticides together on mast cell degranulation is available. To measure the effects, IgE-activated mouse bone marrow-derived mast cells (BMMCs) were treated with imidacloprid and endosulfan, individually, and simultaneously at equi-molar concentrations in tenfold steps ranging from 10-4 to 10-11 M, followed by measuring several allergy-related parameters expressed in BMMCs: the mediator production and influx of Ca2+, the phosphorylation content of NF-κB in the FcεRI signaling pathway. Then, the effects of the mixtures on IgE-induced passive systemic anaphylaxis (PSA) of BALB/c was detectded. This study clearly showed that the application of equi-molar mixtures of both pesticides with 10-4-10-5 M significantly inhibited the IgE-mediated mouse bone marrow-derived mast cells degranulation in vitro and 10-4 M of them decreased IgE-mediated PSA in vivo, as the application of imidacloprid at the same concentration alone did. Morever endosulfan alone had no remarkable stimulatory effects on any of the factors measured. In conclusion, simultaneous application of equi-molar concentrations of both pesticides generally showed highly similar responses compared to the responses to imidacloprid alone, suggesting that the effects of the mixture could be solely attributed to the effects of imidacloprid.


Assuntos
Anafilaxia/induzido quimicamente , Células da Medula Óssea/efeitos dos fármacos , Degranulação Celular/efeitos dos fármacos , Endossulfano/farmacologia , Imunoglobulina E/administração & dosagem , Mastócitos/efeitos dos fármacos , Neonicotinoides/farmacologia , Nitrocompostos/farmacologia , Praguicidas/farmacologia , Anafilaxia/metabolismo , Animais , Células da Medula Óssea/metabolismo , Cálcio/metabolismo , Endossulfano/administração & dosagem , Transporte de Íons , Mastócitos/metabolismo , Camundongos Endogâmicos BALB C , NF-kappa B/metabolismo , Neonicotinoides/administração & dosagem , Nitrocompostos/administração & dosagem , Fosforilação , Receptores de IgE/metabolismo , Transdução de Sinais
17.
J Sci Food Agric ; 97(15): 5168-5175, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28436030

RESUMO

BACKGROUND: High-pressure processing is gaining popularity in the food industry. However, its effect on the Maillard reaction during high-pressure-assisted pasteurization and sterilization is not well documented. This study aimed to investigate the effects of high hydrostatic pressure on the Maillard reaction during these processes using amino acid (lysine or arginine)-sugar (glucose or fructose) solution models. RESULTS: High pressure retarded the intermediate and final stages of the Maillard reaction in the lysine-sugar model. For the lysine-glucose model, the degradation rate of Amadori compounds was decelerated, while acceleration was observed in the arginine-sugar model. Increased temperature not only accelerated the Maillard reaction over time but also formed fluorescent compounds with different emission wavelengths. Lysine reacted with the sugars more readily than arginine under the same conditions. In addition, it was easier for lysine to react with glucose, whereas arginine reacted more readily with fructose under high pressure. CONCLUSION: High pressure exerts different effects on lysine-sugar and arginine-sugar models. © 2017 Society of Chemical Industry.


Assuntos
Arginina/química , Lisina/química , Açúcares/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Pressão Hidrostática , Reação de Maillard , Modelos Químicos
18.
ACS Appl Mater Interfaces ; 8(47): 32557-32564, 2016 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-27933853

RESUMO

Highly efficient flame retardant polyurethane foams with alginate/clay aerogel coatings were fabricated using a freeze-drying method. The microstructure and the interaction of the samples were characterized with scanning electron and optical microscopy (SEM) and (OM). The results show that PU foam has a porous structure with pore sizes of several hundred microns, and that of aerogel ranges from 10 to 30 µm. The PU foam matrix and the aerogel coatings have strong interactions, due to the infusion of aerogel into the porous structure of the foam and the tension generated during the freeze-drying process. Both the PU foam and the aerogel exhibit good thermal stabilities, with onset decomposition temperatures above 240 °C. Combustion parameters, including LOI, TTI, HRR, TSR, FIGRA, CO, and CO2, all indicate significantly reduced fire risk. Total heat release of all but one of the samples was maintained, indicating that the flame retardant mechanism is to decrease flame spread rate by forming a heat, oxygen, and smoke barrier, rather than by reducing fuel content. This facile and inexpensive post-treatment of PU foam could expand its fire safe applications.

19.
ACS Appl Mater Interfaces ; 8(15): 9917-24, 2016 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-27045343

RESUMO

A novel biomass-based mechanically strong and electrically conductive polymer aerogel was fabricated from aniline and biodegradable pectin. The strong hydrogen bonding interactions between polyaniline (PANI) and pectin resulted in a defined structure and enhanced properties of the aerogel. All the resultant aerogels exhibited self-surppoted 3D nanoporous network structures with high surface areas (207-331m(2)/g) and hierarchical pores. The results from electrical conductivity measurements and compressive tests revealed that these aerogels also had favorable conductivities (0.002-0.1 S/m) and good compressive modulus (1.2-1.4 MPa). The aerogel further used as electrode for supercapacitors showed enhanced capacitive performance (184 F/g at 0.5 A/g). Over 74% of the initial capacitance was maintained after repeating 1000 cycles of the cylic voltammetry test, while the capacitance retention of PANI was only 57%. The improved electrochemical performance may be attributed to the combinative properties of good electrical conductivity, BET surface areas, and stable nanoporous structure of the aerogel. Thus, this aerogel shows great potential as electrode materials for supercapacitors.

20.
ACS Appl Mater Interfaces ; 8(2): 1468-77, 2016 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-26710881

RESUMO

Electromagnetic microwave absorption materials have attracted a great deal of attention. Foams for the low density and tunable porosity are considered as ideal microwave absorbents, while with the requirement of improving their inherent electromagnetic properties. In this manuscript, an innovative, easy, and green method was presented to synthesize an electromagnetic functionalized Ni/carbon foam, in which the formation of Ni nanoparticles and carbon occurred simultaneously from an affordable alginate/Ni(2+) foam precursor. The resultant Ni/carbon foam had a low density (0.1 g/cm(-3)) and high Ni nanoparticles loading (42 wt %). These Ni nanoparticles with a diameter of about 50-100 nm were highly crystallized and evenly embedded in porous graphite carbon without aggregation. Also, the resultant foam had a high surface area (451 m(2) g(-1)) and porosity and showed a moderate conductivity (6 S/m) and significant magnetism. Due to these special characteristics, the Ni/carbon foam exhibited greatly enhanced microwave absorption ability. Only with 10 wt % of functional fillers being used in the test template, the Ni/carbon foam based composite could reach an effective absorption bandwidth (below -10 dB) of 4.5 GHz and the minimum reflection value of -45 dB at 13.3 GHz with a thickness of 2 mm, while the traditional carbon foam and nano-Ni powder both showed very weak microwave absorption (the minimum reflection value < -10 dB). This foam was demonstrated to be a lightweight, high performance, and low filler loading microwave absorbing material. Furthermore, the detailed absorption mechanism of the foam was investigated. The result showed that the derived strong dielectric loss, including conductivity loss, interface polarization loss, weak magnetic loss, and naoporosity, contributes a great electromagnetic absorption.

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