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1.
Chem Asian J ; 2021 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-34626095

RESUMO

A new, eco-friendly and noble-metal-free formal [4+2] cycloaddition reaction was developed for the efficient synthesis of biologically interesting poly-substituted pyridines from easily available ketones and imines, whereby two sequential C-C bonds are formed. The given approach features a unique synthetic strategy of imines and ketones with wide substrate scope, good functional group tolerance, mild conditions and operational simplicity, which represents a more direct pathway to synthesize poly-substituted pyridines than traditional methods.

2.
Artigo em Inglês | MEDLINE | ID: mdl-34499488

RESUMO

Photoactuated liquid crystalline elastomer (LCE) materials are gaining much attention in many application fields, but challenges for the precise modulation of their photoresponses still exist. Researchers have explored various optical parameters, such as polarization, intensity, and wavelength, to obtain differential responses. The development of photoactuated LCE materials with wavelength-selective responsiveness is more versatile and has attracted more interest, but such LCE materials are commonly prepared by incorporating different molecular chromophores or dyes into the LCE matrices. When the surface plasmon resonance (SPR) characteristic of nanometals, which can generate strong photothermal conversion, and the difference of SPR absorption wavelength bands of different nanometals are considered, a strategy of constructing wavelength-selective actuation of LCE materials by using the SPR photothermal effect can be demonstrated, as done herein. The LCE nanocomposites doped by nanogold or nanosilver were fabricated and exhibited good SPR absorption but in different wavelength bands of the visible spectrum range. They had strong actuation under light irradiation with the wavelengths being inside their respective absorption band but could not be effectively actuated by the light beyond their respective absorption band. A smart electronic device, implementing a hierarchical structured LCE nanocomposite doped by nanogold and nanosilver in different domains as the two-switch actuator, was prepared and capable of outputting different signals in response to the different wavelength bands filtered from a light source, which released the actuator from the restriction of light scanning direction or position. Our work provides new insights for the convenient and precise photoactuation of the LCE actuators.

3.
Ecotoxicol Environ Saf ; 226: 112827, 2021 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-34571416

RESUMO

Reducing the production of odor during swine breeding has attracted attention. Ammonia (NH3) and hydrogen sulfide (H2S) contributed to the odor emissions from swine breeding because NH3 emissions are high and hydrogen sulfide (H2S) has a low odor threshold. Sodium butyrate reduces the odor emissions caused by NH3 and H2S, but the corresponding mechanism is unclear. After mixing the feces of six fattening pigs, the mixture was used to process in vitro fermentation experiment. The purpose was researching the effect of sodium butyrate reduced NH3 and H2S emissions in swine cecal contents. The control group was denoted CK, and the treatment groups with different sodium butyrate concentrations (0.015%, 0.030% and 0.150%) were denoted L, M and H. The NH3, H2S, total gas production and physicochemical indexes were measured, and the bacterial communities in the fermented product were analyzed by 16 S rDNA sequencing. The results showed that group M reduced NH3, H2S and total gas production by 17.96%, 12.26% and 30.30%, respectively. Sodium butyrate promoted SO42- accumulation and lowered the pH. Importantly, sodium butyrate decreased the relative abundance of bacteria positively correlated with NH3 and H2S production, but increased the negatively correlated ones. Proteobacteria made a greater contribution to reducing emissions than did other bacterial phyla. Our results showed that adding 0.030% sodium butyrate can significantly reduce NH3 and H2S production, which occurred via alterations in the physicochemical indicators to adjust the abundance of the bacteria related to odor production, including Proteobacteria.

4.
Ecotoxicol Environ Saf ; 225: 112815, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34562788

RESUMO

The application of manure compost may cause the transmission of antibiotic resistance genes (ARGs) in agroecological environment, which poses a global threat to public health. However, the driving factors for the transmission of ARGs from animal manure to agroecological systems remains poorly understood. Here, we explored the spatiotemporal variation in ARG abundance and bacterial community composition as well as relative driving factors in a soil-lettuce system amended with swine manure compost. The results showed that ARGs abundance had different variation trends in soil, lettuce phylloplane and endophyere after the application of swine manure compost. The temporal variations of total ARGs abundance had no significant different in soil and lettuce phylloplane, while lettuce endosphere enriched half of ARGs to the highest level at harvest. There was a significant linear correlation between ARGs and integrase genes (IGs). In contrast to the ARGs variation trend, the alpha diversity of soil and phylloplane bacteria showed increasing trends over planting time, and endosphere bacteria remained stable. Correlation analysis showed no identical ARG-related genera in the three parts, but the shared Proteobacteria, Pseudomonas, Halomonas and Chelativorans, from manure compost dominated ARG profile in the soil-lettuce system. Moreover, redundancy analysis and structural equation modelling showed the variations of ARGs may have resulted from the combination of multiple driving factors in soil-lettuce system. ARGs in soil were more affected by the IGs, antibiotic and heavy metals, and bacterial community structure and IGs were the major influencing factors of ARG profiles in the lettuce. The study provided insight into the multiple driving factors contribute to the variations of typical ARGs in different parts of soil-lettuce system, which was conducive to the risk assessment of ARGs in agroecosystem and the development of effective prevention and control measures for ARGs spread in the environment.


Assuntos
Alface , Solo , Animais , Antibacterianos , Resistência Microbiana a Medicamentos , Esterco , Suínos
5.
Physiol Rep ; 9(18): e15017, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34549531

RESUMO

Olfactory receptor 78 (Olfr78) is a G protein-coupled receptor (GPCR) that is expressed in the juxtaglomerular apparatus (JGA) of the kidney as well as the peripheral vasculature, and is activated by gut microbial metabolites. We previously reported that Olfr78 plays a role in renin secretion in isolated glomeruli, and that Olfr78 knockout (KO) mice have lower plasma renin activity. We also noted that in anesthetized mice, Olfr78KO appeared to be hypotensive. In this study, we used radiotelemetry to determine the role of Olfr78 in chronic blood pressure regulation. We found that the blood pressure of Olfr78KO mice is not significantly different than that of their WT counterparts at baseline, or on high- or low-salt diets. However, Olfr78KO mice have depressed heart rates on high-salt diets. We also report that Olfr78KO mice have lower renin protein levels associated with glomeruli. Finally, we developed a mouse where Olfr78 was selectively knocked out in the JGA, which phenocopied the lower renin association findings. In sum, these experiments suggest that Olfr78 modulates renin, but does not play an active role in blood pressure regulation at baseline, and is more likely activated by high levels of short chain fatty acids or hypotensive events. This study provides important context to our knowledge of Olfr78 in BP regulation.

6.
J Agric Food Chem ; 69(35): 10272-10280, 2021 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-34436886

RESUMO

Salt is very important for human health and food seasoning. Recently, several peptides isolated from natural food products have been reported exhibiting a salty taste or a saltiness-enhancing function. In this investigation, taste-active peptides occurring in commercial Chinese fermented soybean curd were isolated and identified using ultrafiltration, gel permeation chromatography, ion-exchange chromatography, and nano-LC/Q-TOF MS/MS. The salty taste-enhancing function of the target fractions was confirmed by both a rat taste cell model and/or human sensory evaluation. Four decapeptides were found as taste-active compounds. Among them, peptide E (EDEGEQPRPF) was the most potent saltiness-enhancing peptide: 0.4 mg/mL in 50 mmol/L NaCl solution could increase its salty perception equivalent to the salt level of 63 mmol/L NaCl reference solution. The sequence of the peptide has been found in the α'-subunit of ß-conglycinin [Glycine max]. The remaining peptides V (VGPDDDEKSW), DD (DEDEQPRPIP), and DG (DEGEQPRPFP) showed umami and kokumi tastes as well as a weak saltiness-enhancing sensation. These findings suggest that the decapeptide EDEGEQPRPF could be a possible alternative to partially reduce the amount of sodium intake without compromising for saltiness.


Assuntos
Cloreto de Sódio , Alimentos de Soja , Animais , China , Peptídeos , Ratos , Alimentos de Soja/análise , Espectrometria de Massas em Tandem , Paladar
7.
Vaccine ; 39(24): 3304-3309, 2021 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-33980399

RESUMO

OBJECTIVE: To analyze the serotype distribution and drug resistance of Streptococcus pneumoniae isolated from hospitalized patients of all ages in Zhongjiang county, Sichuan province, where the young children have just begun to vaccinate the PCV13 in private sector. METHODS: Serotypes were determined for 387 isolates of S. pneumoniae by Quellung reaction. Antibiotic susceptibility was tested with the E-test or disc diffusion method. RESULTS: The most common serotypes were type 19F and confirmed for 88 isolates (22.7%), followed by 19A (15.0%), 6B (7.8%), 16F (7.8%), 23F (7.0%) and 15A (4.4%). The coverage rates of PCV13 and PPSV23 were 63.3% and 65.1%. With the increase of age, the proportion of PCV13 types decreased significantly, from 71.3% (<2 years old) to 41.9% (≥60 years old). The intermediate rate and resistance rate of the isolates to oral penicillin were 48.6% and 45.2%, respectively. The resistance rate of erythromycin was high (94.4%). The PCV13 isolates was more resistant to penicillin than the non-PCV13 ones. CONCLUSION: The PCV13 coverage rate in pediatric isolates was higher than those in adult isolates. The adults, especially the elderly, may be the reservoir of non-PCV13 types. It is necessary to investigate the serotype distribution of S. pneumoniae based on all age population to assess potential epidemics of non-vaccine serotype associated with PCVs administration.


Assuntos
Infecções Pneumocócicas , Streptococcus pneumoniae , Adulto , Idoso , Antibacterianos/farmacologia , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Humanos , Lactente , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Infecções Pneumocócicas/epidemiologia , Infecções Pneumocócicas/prevenção & controle , Vacinas Pneumocócicas , Sorogrupo , Sorotipagem
8.
Int J Mol Med ; 47(5)2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33786607

RESUMO

Diabetic osteoporosis is a serious complication of diabetes affecting human bones. Uncarboxylated osteocalcin (GluOC), a small molecular protein specifically synthesized and secreted from osteoblasts, is of importance in regulating energy metabolism. In previous studies, the authors demonstrated that high glucose inhibited osteoblastic differentiation, but promoted adipocytic differentiation. GluOC promoted osteogenic and inhibited adipogenic differentiation under high glucose conditions. However, the corresponding receptors and signaling pathways through which GluOC exerts its effects on MC3T3E1 cells remain elusive. Thus, in the present study, Cell Counting kit­8 assays and western blot analysis were performed to assess the proliferation of MC3T3E1 cells. Alizarin Red S or Oil Red O staining, as well as reverse transcription­quantitative PCR analysis were performed to examine osteogenic and adipogenic differentiation. The cells were transfected with short interfering RNA or inhibitors to investigate the possible signaling pathways involved. The results revealed that G­protein coupled receptor, class C, group 6, subtype A (GPRC6A) receptor expression was markedly increased following the addition of GluOC to the MC3T3E1 cells. GPRC6A silencing decreased osteogenic gene expression, while it increased adipogenic gene expression. Furthermore, GluOC promoted osteoblast differentiation via the subsequent activation of the cyclic AMP (cAMP)/protein kinase A(PKA)/AMP­activated protein kinase (AMPK) signaling pathway in MC3T3E1 cells. On the whole, the results of the present study suggest that GluOC reverses the high glucose­induced inhibition of osteogenic differentiation via the GPRC6A/cAMP/PKA/AMPK signaling pathway in MC3T3E1 cells, and thus may prove to be beneficial in the treatment of diabetic osteoporosis.

9.
Ecotoxicol Environ Saf ; 213: 112003, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33588188

RESUMO

A green rust-coated expanded perlite (GR-coated Exp-p) microelectrode was synthesized and incorporated into a column-mode three-dimensional electrokinetic (3D-EK) platform to effectively pursue a continuous Cr(VI) removal from the aqueous solution. Brucite-like layers of GR were decorated onto the Exp-p material. The molar ratio of Fe(II) to Fe(III) played a most vital role among the three synthesis factors in influencing the performance of the particle electrode. For the equilibrium adsorption experiments, the target maximum adsorption capacity of 122 mg/g was predicted by a target optimizer and desirability function at the conditions following the pH of 4.7, the initial concentration of 172.4 mg/L, the dosage of 0.28 g/L, and the temperature of 28.96 °C, respectively. SO42-, Cl-, and NO3- fiercely competed with Cr(VI) anions in the acidic conditions for the locally positive sites. A low concentration and a slow flow were favored in the column-mode 3D-EK platform. The pseudo-first-order and Langmuir models were suitable for describing the kinetics and isotherms of the adsorption process, respectively. Cr(VI) anions were electrostatically attracted to the silanol groups and GR surface of the adsorbent, subsequently reduced in both heterogeneity and homogeneity, and finally immobilized by coordinating with silanediol groups and silanetriol groups.


Assuntos
Cromo/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Adsorção , Óxido de Alumínio , Ânions , Eletrodos , Compostos Férricos , Concentração de Íons de Hidrogênio , Cinética , Dióxido de Silício , Temperatura , Água , Poluentes Químicos da Água/análise
10.
ACS Nano ; 15(2): 2933-2946, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33529007

RESUMO

Transarterial radioembolization (TARE) is considered the standard treatment for intermediate-stage hepatocellular carcinoma (HCC). Iodine-131 (131I)-labeled lipiodol TARE is an effective treatment for HCC but has been withdrawn due to its poor retention in tumor lesions and significant distribution in normal tissues with severe side effects. In this work, a highly tumor-specific 131I-TARE agent with long-time retention is developed by simply introducing tyrosine to poly(vinyl alcohol) (PVA) drug-eluting microbeads (Tyr-PVA-DEBs). The labeling efficiency of 131I-labeled microbeads remains above 85% in 50% serum for 31 days. Micro-single-photon emission computed tomography/computed tomography (µSPECT/CT) evidences that the 131I-labeled microbeads accumulate in the orthotopic N1S1 hepatoma of rats for 31 days following intra-arterial injection. The cumulative radiation dose per cubic centimeter of the tumor is at least 13 678-fold higher than that of normal tissues. The highly tumor-selective radiation of the 131I-labeled microbeads allows localized delivery of 345.04 ± 139.16 Gy to the tumor following a single injection dose as low as 0.2 mCi of 131I. Moreover, the 131I-labeled microbeads are loaded with doxorubicin hydrochloride (DOX) through the carboxy groups on tyrosine of the polymer. The 131I-DOX-loaded microbeads present a synergetic antitumor effect without recurrence in comparison with the microbeads labeled with 131I or loading DOX alone, attributed to the sensitization of DOX to 131I-induced ionizing radiation damage to DNA under the embolization-induced hypoxia. Our results demonstrate a high tumor retention of 131I-labeled embolic agent for low-dose transarterial radio-chemoembolization (TARCE) with a synergetic therapeutic effect on treating HCC, showing potential for clinical application.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Animais , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/tratamento farmacológico , Radioisótopos do Iodo , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/tratamento farmacológico , Microesferas , Ratos
11.
J Pharmacol Exp Ther ; 377(1): 39-50, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33414131

RESUMO

Short-chain fatty acids (SCFAs) are metabolites produced almost exclusively by the gut microbiota and are an essential mechanism by which gut microbes influence host physiology. Given that SCFAs induce vasodilation, we hypothesized that they might have additional cardiovascular effects. In this study, novel mechanisms of SCFA action were uncovered by examining the acute effects of SCFAs on cardiovascular physiology in vivo and ex vivo. Acute delivery of SCFAs in conscious radiotelemetry-implanted mice results in a simultaneous decrease in both mean arterial pressure and heart rate (HR). Inhibition of sympathetic tone by the selective ß-1 adrenergic receptor antagonist atenolol blocks the acute drop in HR seen with acetate administration, yet the decrease in mean arterial pressure persists. Treatment with tyramine, an indirect sympathomimetic, also blocks the acetate-induced acute drop in HR. Langendorff preparations show that acetate lowers HR only after long-term exposure and at a smaller magnitude than seen in vivo. Pressure-volume loops after acetate injection show a decrease in load-independent measures of cardiac contractility. Isolated trabecular muscle preparations also show a reduction in force generation upon SCFA treatment, though only at supraphysiological concentrations. These experiments demonstrate a direct cardiac component of the SCFA cardiovascular response. These data show that acetate affects blood pressure and cardiac function through parallel mechanisms and establish a role for SCFAs in modulating sympathetic tone and cardiac contractility, further advancing our understanding of the role of SCFAs in blood pressure regulation. SIGNIFICANCE STATEMENT: Acetate, a short-chain fatty acid, acutely lowers heart rate (HR) as well as mean arterial pressure in vivo in radiotelemetry-implanted mice. Acetate is acting in a sympatholytic manner on HR and exerts negative inotropic effects in vivo. This work has implications for potential short-chain fatty acid therapeutics as well as gut dysbiosis-related disease states.


Assuntos
Acetatos/farmacologia , Pressão Sanguínea , Ácidos Graxos Voláteis/farmacologia , Frequência Cardíaca , Coração/efeitos dos fármacos , Contração Miocárdica , Acetatos/administração & dosagem , Animais , Ácidos Graxos Voláteis/administração & dosagem , Feminino , Coração/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Sistema Nervoso Simpático/efeitos dos fármacos , Sistema Nervoso Simpático/fisiologia
12.
ACS Nano ; 14(5): 6305-6322, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32378877

RESUMO

Previous studies on the treatment of hepatic cirrhosis have been focusing on how to inhibit liver fibrosis, while ignoring liver inflammation, a key and underlying factor that promotes cirrhosis. High mobility group box-1 (HMGB1) protein, a pro-inflammatory factor and fibroblast chemokine, can promote the proliferation of hepatic stellate cells (HSCs) and the development of hepatic inflammation and fibrosis, playing a key role in cirrhosis formation. In this study, we prepared pPB peptide (C*SRNLIDC*)-modified and HMGB1-siRNA-loaded stable nucleic acid lipid nanoparticles (HMGB1-siRNA@SNALP-pPB) to effectively treat hepatic cirrhosis by their dual antifibrotic and anti-inflammatory activities. The pPB peptide-modified and heat shock protein 47 (HSP47)-siRNA-loaded stable nucleic acid lipid nanoparticles (HSP47-siRNA@SNALP-pPB), which have only an antifibrotic effect without an anti-inflammatory effect, was used as control. The results demonstrated that HMGB1-siRNA@SNALP-pPB were actively targeted to HSCs by the mediation of pPB peptide, effectively silenced the HMGB1 gene, inhibited the activation and proliferation of HSCs, reduced the release of HMGB1 protein, inhibited collagen deposition and fibrosis formation in the liver, and significantly prolonged the survival time of cirrhotic mice models. HMGB1-siRNA@SNALP-pPB showed a stronger therapeutic effect on liver cirrhosis than HSP47-siRNA@SNALP-pPB. This study provides an actively targeted siRNA delivery system for cirrhosis treatment based on the dual antifibrotic and anti-inflammatory effects. In addition, this study clarified the role of inflammatory problems in cirrhosis treatment in addition to liver fibrosis, providing a useful idea and scientific basis for the development of cirrhosis treatment strategies in the future.


Assuntos
Células Estreladas do Fígado , Nanopartículas , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Células Estreladas do Fígado/patologia , Lipídeos , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/patologia , Camundongos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/uso terapêutico
13.
Nanotechnology ; 31(29): 295101, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32203949

RESUMO

Despite the promising target of immunosuppressive enzyme indoleamine-2,3-dioxygenase (IDO) for cancer immunotherapy, IDO blockade monotherapy does not show significant benefit to cancer patients in the clinic. Recent research has focused on the combinatorial therapy of the IDO inhibitor and the immune checkpoint blockade or chemotherapy. Here, we synthesize a drug conjugate methyltryptophan-paclitaxel (MP) by linking the IDO inhibitor, D-1-methyltryptophan (D-1MT), to the chemotherapeutic agent, paclitaxel (PTX), through an ester bond. MP exhibits a similar tubulin-stabilizing effect to PTX. Like PTX, MP binds to human serum albumin to form albumin-bound MP nanoparticles (MP NPs) with a particle size of ∼115 nm in diameter. MP NPs significantly improve the tumor concentration of D-1MT due to the hydrolysis of MP in tumors. The codelivery of PTX and D-1MT offered by MP NPs in tumors significantly enhances the anti-tumor effect compared with the albumin-bound PTX NPs. Immune cell phenotyping reveals that MP NPs ameliorate the immune environment through increasing the number of the effector CD8+ T cells, and decreasing the population of regulatory T cells and granulocyte-like myeloid-derived suppressor cells. These results prove that the design of the twin drug from the IDO inhibitor and PTX synergizes the anti-tumor effect and shows promise in clinical translation.


Assuntos
Albuminas/farmacologia , Antineoplásicos/farmacologia , Melanoma Experimental/tratamento farmacológico , Paclitaxel/farmacologia , Triptofano/análogos & derivados , Albuminas/química , Animais , Antineoplásicos/química , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/metabolismo , Linhagem Celular Tumoral , Composição de Medicamentos , Sinergismo Farmacológico , Feminino , Imunoterapia , Indolamina-Pirrol 2,3,-Dioxigenase/antagonistas & inibidores , Melanoma Experimental/imunologia , Camundongos , Nanopartículas , Paclitaxel/química , Tamanho da Partícula , Linfócitos T Reguladores/efeitos dos fármacos , Linfócitos T Reguladores/metabolismo , Resultado do Tratamento , Triptofano/química , Triptofano/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Wei Sheng Yan Jiu ; 49(6): 984-989, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33413776

RESUMO

OBJECTIVE: To analyze the contents of fat-soluble vitamins in different kinds of eggs and egg products in Hangzhou City. METHODS: The contents of fat-soluble vitamin A, vitamin E, vitamin K_1 and vitamin K_2(menaquinone-4, menaquinone-7 and menaquinone-9) in eggs and egg products were determined by the high-performance liquid chromatography method. The contents of vitamin D were determined by high performance liquid chromatography-tandem mass spectrometry. The determined contents were compared with the corresponding nutrient reference values. RESULTS: The contents of vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products were 64-278 µg RAE/100 g edible, 0. 2-9. 6 µg/100 g edible, 0. 59-2. 31 mg α-TE/100 g edible and 9. 5-84. 8 µg/100 g edible, respectively, accounting for 4%-192% of the corresponding nutrient reference values. The contents of fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in duck, goose and quail eggs were higher than those in chicken eggs and pigeon eggs. CONCLUSION: There are some differences in fat-soluble vitamin A, vitamin D, vitamin E and vitamin K in different eggs and egg products, but there is no significant difference between groups.


Assuntos
Ovos , Vitaminas , Animais , Cromatografia Líquida de Alta Pressão , Ovos/análise , Vitamina A/análise , Vitamina D , Vitaminas/análise
15.
Wei Sheng Yan Jiu ; 49(6): 990-997, 2020 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-33413777

RESUMO

OBJECTIVE: Comparison and analysis of α-, ß-, γ-, δ-tocopherol(T) and α-, ß-, γ-, δ-tocotrienol(T3) in 44 species of seafood and aquatic products is under processed to enrich the database of food composition in China and provide a scientific reference for dietary intake choice. METHODS: Quantitative and correlation analysis of eight vitamin E isomers were based on external calibration method with reversed-phase high-performance liquid chromatography-fluorescence detector, after hot saponification with alkaline and liquid-liquid extraction. RESULTS: The content of α-tocopherol equivalent(α-TE) in seafood and aquatic products varied greatly(from 0. 10 to 4. 01 mg/100 g edible), as well as the isomer forms. Aspect of vitamin E forms in aquatic fish, detection rates of α-T and α-T3 were both 100%, while the rates of γ-T and γ-T3 were 31. 58% and 68. 42%, respectively. Aspect of vitamin E forms in sea fish, detection rates α-T3, γ-T and γ-T3 were 28. 57%, 28. 57% and 35. 71%, respectively, while the rate of α-T was 100%. The form of vitamin E isomers in fish was at some extent different when they raise up in wild and farming environment, whereas there was no significant different in content of isomers. For shrimp and crabs, the content of α-TE was also various(from 0. 31 to 14. 27 mg/100 g edible), whereas α-T was the primary vitamin E form. And the content of α-T in female crabs was a little higher than that in male crabs, without statistic difference. With respect to correlation analysis, there was a strong correlation between γ-T and α-T3 in sea fish, while weak correlation of isomers in aquatic fish and certain correlations of isomers in shrimp and crab. CONCLUSION: The level of vitamin E content in seafood and aquatic products are quite different. Thus, it will bring in different effects on total activity and intake of vitamin E isomers by consumption of different species of seafood and aquatic products.


Assuntos
Tocotrienóis , Vitamina E , Animais , China , Feminino , Masculino , Alimentos Marinhos , Tocoferóis
16.
ACS Nano ; 13(9): 10242-10260, 2019 09 24.
Artigo em Inglês | MEDLINE | ID: mdl-31397999

RESUMO

Cancer photodynamic therapy (PDT) represents an attractive local treatment in combination with immunotherapy. Successful cancer PDT relies on image guidance to ensure the treatment accuracy. However, existing nanotechnology for co-delivery of photosensitizers and image contrast agents slows the clearance of PDT agents from the body and causes a disparity between the release profiles of the imaging and PDT agents. We have found that the photosensitizer Chlorin e6 (Ce6) is inherently bound to immunoglobulin G (IgG) in a nanomolarity range of affinity. Ce6 and IgG self-assemble to form the nanocomplexes termed Chloringlobulin (Chlorin e6 + immunoglobulin G). Chloringlobulin enhances the Ce6 concentration in the tumor without changing its elimination half-life in blood. Utilizing the immune checkpoint inhibitor antiprogrammed death ligand 1 (PD-L1) (αPD-L1) to prepare αPD-L1 Chloringlobulin, we have demonstrated a combination of Ce6-based red-light fluorescence image-guided surgery, stereotactic PDT, and PD-L1 blockade therapy of mice bearing orthotopic glioma. In mice bearing an orthotopic colon cancer model, we have prepared another Chloringlobulin that allows intraoperative fluorescence image-guided PDT in combination with PD-L1 and cytotoxic T lymphocyte antigen 4 (CTLA-4) dual checkpoint blockade therapy. The Chloringlobulin technology shows great potential for clinical translation of combinatorial intraoperative fluorescence image-guided PDT and checkpoint blockade therapy.


Assuntos
Imunoglobulina G/metabolismo , Imunoterapia , Cuidados Intraoperatórios , Neoplasias/terapia , Fotoquimioterapia , Porfirinas/química , Animais , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/metabolismo , Antígeno CTLA-4/antagonistas & inibidores , Antígeno CTLA-4/metabolismo , Linhagem Celular Tumoral , Feminino , Fluorescência , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Neoplasias/cirurgia , Porfirinas/farmacocinética , Ratos , Distribuição Tecidual
17.
Soft Matter ; 15(30): 6116-6126, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31286128

RESUMO

In this work, according to the characteristic of surface plasmon resonance (SPR) of metallic nanoparticles, we investigated the photo actuation performance of a liquid crystalline elastomer (LCE) nanocomposite with incorporated gold nanoparticles (nano-gold/LCE nanocomposite). The nano-gold/LCE nanocomposites were fabricated by incorporating gold nanoparticles into a polysiloxane-based LCE matrix via a novel experimental protocol, and characterized by a well-developed SPR absorption band in the visible spectrum range. The nano-gold/LCE nanocomposites demonstrated strong actuation upon irradiation with a quasi-daylight source; the reason lay in that the SPR response of gold nanoparticles performed efficient energy conversion from light energy to thermal energy, and thus offered an activation pathway for the nematic-isotropic transition of the LCE matrix. The nano-gold/LCE nanocomposites underwent rapid maximum axial contraction up to about one third of the original length under light irradiation, and this photo-stimulated muscle-like actuation was fully reversible via the on-off switching of the light source. The photo actuation properties of nano-gold/LCE nanocomposites with varying irradiation intensities and gold nanoparticle content were also investigated. In addition, the nano-gold/LCE nanocomposites demonstrated superior optical nonlinear properties, and revealed potential for the application area of mode-locking for laser technology.

18.
BMC Plant Biol ; 19(1): 323, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31319801

RESUMO

BACKGROUND: Exogenous 5-aminolevulinic acid (ALA) positively regulates plants chlorophyll synthesis and protects them against environmental stresses, although the protection mechanism is not fully clear. Here, we explored the effects of ALA on chlorophyll synthesis in tomato plants, which are sensitive to low temperature. We also examined the roles of the glutathione S-transferase (GSTU43) gene, which is involved in ALA-induced tolerance to oxidation stress and regulation of chlorophyll synthesis under low temperature. RESULTS: Exogenous ALA alleviated low temperature caused chlorophyll synthesis obstacle of uroporphyrinogen III (UROIII) conversion to protoporphyrin IX (Proto IX), and enhanced the production of chlorophyll and its precursors, including endogenous ALA, Proto IX, Mg-protoporphyrin IX (Mg-proto IX), and protochlorophyll (Pchl), under low temperature in tomato leaves. However, ALA did not regulate chlorophyll synthesis at the level of transcription. Notably, ALA up-regulated the GSTU43 gene and protein expression and increased GST activity. Silencing of GSTU43 with virus-induced gene silencing reduced the activities of GST, superoxide dismutase, catalase, ascorbate peroxidase, and glutathione reductase, and increased the membrane lipid peroxidation; while fed with ALA significant increased all these antioxidase activities and antioxidant contents, and alleviated the membrane damage. CONCLUSIONS: ALA triggered GST activity encoded by GSTU43, and increased tomato tolerance to low temperature-induced oxidative stress, perhaps with the assistance of ascorbate- and/or a glutathione-regenerating cycles, and actively regulated the plant redox homeostasis. This latter effect reduced the degree of membrane lipid peroxidation, which was essential for the coordinated synthesis of chlorophyll.


Assuntos
Ácido Aminolevulínico/metabolismo , Clorofila/metabolismo , Genes de Plantas/fisiologia , Glutationa Transferase/metabolismo , Lycopersicon esculentum/genética , Proteínas de Plantas/metabolismo , Ácido Aminolevulínico/farmacologia , Resposta ao Choque Frio , Glutationa Transferase/genética , Homeostase/efeitos dos fármacos , Peroxidação de Lipídeos , Lycopersicon esculentum/efeitos dos fármacos , Lycopersicon esculentum/metabolismo , Lycopersicon esculentum/fisiologia , Oxirredução/efeitos dos fármacos , Proteínas de Plantas/genética
19.
J Biomed Nanotechnol ; 15(8): 1771-1780, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31219009

RESUMO

Photothermal therapy (PTT) is a powerful technique for tumor ablation. However, there is a problem that PTT cannot accurately locate the tumor site, so it is easy to cause heat damage to the surrounding normal tissues. In this study, PEGylated amorphous manganese dioxide (MnO2) coated polydopamine (PDA) core-shell nanoparticles (PDA@MnO2-PEG) with regular morphology and uniform dimensions were prepared for acid-sensitive magnetic resonance imaging-guided tumor photothermal therapy. The results showed that amorphous MnO2 shell provided markedly acid-sensitive T1-weighted magnetic resonance imaging (MRI). The relaxation rate (r1 value) of PDA@MnO2-PEG in pH=7.4 was measured to be 0.310 mM-1·S-1, while that in pH=6 became 4.364 mM-1·S-1. In mice tumor models, MRI of tumors exhibited dramatically whitening effects compared with the signal before injection. Besides, the in vivo experiments revealed that the tumors in PTT group with PDA@MnO2-PEG injection and NIR laser irradiation were almost eliminated within 14 days, indicating the effective photothermal therapy of tumor generated by the PDA core. In conclusion, we successfully synthesized amorphous MnO2 coated PDA core-shell nanoparticles with the function of acid-sensitive magnetic resonance imaging guided photothermal therapy, which provide a new approach for improving the effect of photothermal therapy of tumors.


Assuntos
Nanopartículas , Animais , Indóis , Imageamento por Ressonância Magnética , Compostos de Manganês , Camundongos , Óxidos , Polímeros
20.
Nat Commun ; 10(1): 2206, 2019 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-31101816

RESUMO

Fluorophores with donor-acceptor-donor groups with the emission spanning the second near-infrared window (NIR-II) have recently received great attention for biomedical application. Yet, the mechanism underlying the equilibrium between fluorescence (radiative decay) and photothermal effect (non-radiative decay) of these fluorophores remains elusive. Here, we demonstrate that a lipophilic NIR-II fluorophore, BPBBT, possesses both twisted intramolecular charge transfer (TICT) and aggregation-induced emission (AIE) characteristics. Human serum albumin (HSA) binds to BPBBT, which changes the planarity of the fluorophore and restricts its intramolecular rotation. The binding results in alteration to the equilibrium between AIE and TICT state of BPBBT, tailoring its fluorescence and photothermal efficiency. Under the guidance of intraoperative NIR-II fluorescence image, the prepared HSA-bound BPBBT nanoparticles delineate primary orthotopic mouse colon tumor and metastatic lesions with dimensions as small as 0.5 mm × 0.3 mm, and offer photothermal ablation therapy with optimized timing, dosing and area of the laser irradiation.

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