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The primary and initial manifestations of hypertension encompass arterial hypoelasticity and histiocyte senescence. Oxidative stress plays a pivotal role in the progression of senescence. Elevated intracellular oxidative stress levels will directly induce cell damage, disrupt normal physiological signal transduction, which can cause mitochondrial dysfunction to accelerate the process of senescence. Alizarin, an anthraquinone active ingredient isolated from Rubia cordifolia L., has a variety of pharmacological effects, including antioxidant, anti-inflammatory and anti-platelet. Nevertheless, its potential in lowering blood pressure (BP) and mitigating hypertension-induced vascular senescence remains uncertain. In this study, we used spontaneously hypertensive rats (SHR) and human umbilical vein endothelial cells (HUVECs) to establish a model of vascular senescence in hypertension. Our aim was to elucidate the mechanisms underpinning the vascular protective effects of Alizarin. By assessing systolic blood pressure (SBP) and diastolic blood pressure (DBP), H&E staining, SA-ß-Gal staining, vascular function, oxidative stress levels, calcium ion concentration and mitochondrial membrane potential, we found that Alizarin not only restored SBP and increased endothelium-dependent relaxation (EDR) in SHR, but also inhibited oxidative stress-induced mitochondrial damage and significantly delayed the vascular senescence effect in hypertension, and the mechanism may be related to the activation of VEGFR2/eNOS signaling pathway.
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Antraquinonas , Antihipertensivos , Senescencia Celular , Células Endoteliales de la Vena Umbilical Humana , Hipertensión , Mitocondrias , Óxido Nítrico Sintasa de Tipo III , Estrés Oxidativo , Ratas Endogámicas SHR , Transducción de Señal , Receptor 2 de Factores de Crecimiento Endotelial Vascular , Estrés Oxidativo/efectos de los fármacos , Animales , Humanos , Ratas , Mitocondrias/metabolismo , Mitocondrias/efectos de los fármacos , Antraquinonas/farmacología , Senescencia Celular/efectos de los fármacos , Antihipertensivos/farmacología , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Óxido Nítrico Sintasa de Tipo III/metabolismo , Hipertensión/metabolismo , Hipertensión/tratamiento farmacológico , Receptor 2 de Factores de Crecimiento Endotelial Vascular/metabolismo , Transducción de Señal/efectos de los fármacos , Masculino , Presión Sanguínea/efectos de los fármacos , Ratas Endogámicas WKYRESUMEN
Electronic skins have received increasing attention due to their great application potential in wearable electronics. Meanwhile, tremendous efforts are still needed for the fabrication of multifunctional composite hydrogels with complex structures for electronic skins via simple methods. In this work, a novel three-dimensional (3D) printing composite hydrogel with stretchability, conductivity, and strain-sensing ability is produced using a one-step photocuring method to achieve a dual-signal response of the electronic skin. The composite hydrogel exhibits a triple-network structure composed of silk microfibers (SMF), regenerated silk fibroin (RSF), and polyacrylamide (PAM). The establishment of triple networks is based on the electrostatic interaction between SMF and RSF, as well as the chemically cross-linked RSF and PAM. Thanks to its specific structure and components, the composite hydrogel possesses enhanced mechanical properties (elastic modulus of 140 kPa, compressive stress of 21 MPa, and compression modulus of 600 kPa) and 3D printability while retaining stretchability and flexibility. The interaction between negatively charged SMF and cations in phosphate-buffered saline endows the composite hydrogel with good conductivity and strain-sensing ability after immersion in a low-concentration (10 mM) salt solution. Moreover, the 3D printing composite hydrogel scaffold successfully realizes real-time monitoring. Therefore, the proposed hydrogel-based ionic sensor is promising for skin tissue engineering, real-time monitoring, soft robotics, and human-machine interfaces.
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Resinas Acrílicas , Conductividad Eléctrica , Fibroínas , Hidrogeles , Impresión Tridimensional , Dispositivos Electrónicos Vestibles , Fibroínas/química , Resinas Acrílicas/química , Hidrogeles/química , Humanos , BiónicaRESUMEN
Neonicotinoids (NEOs) have indeed become the most widely used insecticides worldwide. Concerns have been raised about their potential impact on newborns due to maternal exposure and their unique neurotoxic mode of action. However, it is still poorly understood whether in utero exposure of pregnant women to environmental NEOs and their metabolites can cause carryover effects on vulnerable newborns and subsequent health consequences. In this study, we determined the concentrations of 13 NEOs and their metabolites in the first urine collected from 92 newborns, both preterm and full-term, in southern China during 2020 and 2021. NEOs and their metabolites were identified in 91 urine samples, with over 93% of samples containing a cocktail of these compounds, confirming their maternal-fetal transfer. N-desmethyl-acetamiprid, imidaclothiz, clothianidin and flonicamid were the most commonly detected analytes, with detection frequencies of 59-87% and medians of 0.024-0.291 ng/mL in the urine. The relative abundance of imidaclothiz was significantly higher in preterm newborns, those with head circumferences below 33 cm, birth lengths less than 47 cm, and weights below 2500 g (p < 0.05). When comparing newborns in the 2nd quartile of imidaclothiz concentrations with those in the 1st quartile, we observed a significant increase in the odds of preterm outcomes in the unadjusted model (odds ratio = 3.24, 95% confidence interval = 1.02-10.3). These results suggest that exposure to elevated concentrations of imidaclothiz may be associated with preterm birth.
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Insecticidas , Nacimiento Prematuro , Tiazoles , Humanos , Recién Nacido , Femenino , Embarazo , Insecticidas/análisis , Neonicotinoides , China , NitrocompuestosRESUMEN
Vascular dementia (VD) is one of the most common causes of dementia, taking account for about 20% of all cases. Although studies have found that selenium supplementation can improve the cognitive ability of Alzheimer's patients, there is currently no research on the cognitive impairment caused by VD. This study aimed to investigate the role and mechanism of Amorphous selenium nanodots (A SeNDs) in the prevention of VD. The bilateral common carotid artery occlusion (BCCAO) method was used to establish a VD model. The neuroprotective effect of A SeNDs was evaluated by Morris water maze, Transcranial Doppler TCD, hematoxylin-eosin (HE) staining, Neuron-specific nuclear protein (Neu N) staining and Golgi staining. Detect the expression levels of oxidative stress and Calcium-calmodulin dependent protein kinase II (CaMK II), N-methyl-D-aspartate receptor subunit NR2A, and postsynaptic dense protein 95 (PSD95). Finally, measure the concentration of calcium ions in neuronal cells. The results showed that A SeNDs could significantly improve the learning and memory ability of VD rats, restore the posterior arterial blood flow of the brain, improve the neuronal morphology and dendritic remodeling of pyramidal cells in hippocampal CA1 area, reduce the level of oxidative stress in VD rats, increase the expression of NR2A, PSD95, CaMK II proteins and reduce intracellular calcium ion concentration, but the addition of selective NR2A antagonist NVP-AAMO77 eliminated these benefits. It suggests that A SeNDs may improve cognitive dysfunction in vascular dementia rats by regulating the NMDAR pathway.
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Demencia Vascular , Selenio , Ratas , Animales , Demencia Vascular/tratamiento farmacológico , Demencia Vascular/metabolismo , Selenio/farmacología , Selenio/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Calcio/metabolismo , Estrés Oxidativo , Hipocampo , Neuronas/metabolismo , Aprendizaje por LaberintoRESUMEN
BACKGROUND: In a previous study, we found that traditional Chinese medicine (TCM) alleviated the clinical symptoms and improved the quality of life (QoL) in patients with hepatocellular carcinoma (HCC). OBJECTIVES: A cohort was continuously followed up to determine the impact of the TCM adjuvant therapies on the prognosis of HCC after conventional treatments. METHODS: We did a retrospective monocentric cohort study including 175 eligible patients. The participants who received TCM adjuvant therapies were termed as TCM group. For the purpose of stratification analysis, the patients who received TCM adjuvant therapies over 3 months per year were further classified into the high frequency group, while the rest of the TCM users were classified into the low frequency group. Non-users were recorded as the control group. The primary outcome was overall survival (OS) and the secondary outcome was the mean progression-free survival (mPFS) primarily introduced in this study, referring to the time from initial diagnosis to the latest progression over the number of disease progressions. Analyses used Cox proportional hazards and Kaplan-Meier (K-M) methods, adjusted for stratification factors. RESULTS: Until June 30, 2021, 56 patients survived, 21 patients were lost to follow-up, and 98 patients died from the disease. Each disease progression of every individual was recorded, and most of the PFS was within 1 year. The baseline data of the allocated groups were balanced, the result revealed that TCM adjuvant therapies might have little influence on OS (P = .129). However, the 1, 3, and 5-year progression-free survival rates of the patients in TCM and control group were 68.75%, 37.50%; 25.00%, 8.33% and 8.33%, 2.08%, respectively, indicating TCM use significantly extended the mPFS, and decreased the risk of disease progression by a factor of 0.676 (P = .006). In the patients with BCLC stage B HCC, compared with controls, a 37-month median OS advantage in the high frequency group was noted (P = .045); and the high frequency of TCM use significantly suppressed disease progression (P = .001). CONCLUSIONS: The present study revealed that TCM adjuvant therapies could postpone disease progression in HCC. Furthermore, using TCM over 3 months per year might extend OS in patients with intermediate HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Medicina Tradicional China , Estudios Retrospectivos , Calidad de Vida , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Estudios de Cohortes , Pronóstico , Progresión de la EnfermedadRESUMEN
Neural interface is a powerful tool to control the varying neuron activities in the brain, where the performance can directly affect the quality of recording neural signals and the reliability of in vivo connection between the brain and external equipment. Recent advances in bioelectronic innovation have provided promising pathways to fabricate flexible electrodes by integrating electrodes on bioactive polymer substrates. These bioactive polymer-based electrodes can enable the conformal contact with irregular tissue and result in low inflammation when compared to conventional rigid inorganic electrodes. In this review, we focus on the use of silk fibroin and cellulose biopolymers as well as certain synthetic polymers to offer the desired flexibility for constructing electrode substrates for a conformal neural interface. First, the development of a neural interface is reviewed, and the signal recording methods and tissue response features of the implanted electrodes are discussed in terms of biocompatibility and flexibility of corresponding neural interfaces. Following this, the material selection, structure design and integration of conformal neural interfaces accompanied by their effective applications are described. Finally, we offer our perspectives on the evolution of desired bioactive polymer-enabled neural interfaces, regarding the biocompatibility, electrical properties and mechanical softness.
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Neuronas , Polímeros , Polímeros/química , Reproducibilidad de los Resultados , Neuronas/fisiología , Encéfalo/fisiología , Electrodos ImplantadosRESUMEN
Hepatocellular Carcinoma (HCC) is one of the most common malignant tumors in the world. Although the current treatment methods for HCC are gradually increasing, its efficacy still cannot meet the medical needs of patients with liver cancer, and new and effective treatment strategies are urgently needed. The total flavonoids of Oldenlandia diffusa (FOD) are the main active components in Oldenlandia diffusa, which have anti-inflammatory, antioxidant and anti-tumor effects, but their mechanism of action in liver cancer is unclear. In this study, we examined the effect of FOD on HCC. Using both in vitro and in vivo models, we confirmed that FOD inhibited HCC proliferation and induced apoptosis and autophagy. Mechanistic studies have shown that FOD induces apoptosis and activates autophagy in HCC cells by inducing endoplasmic reticulum stress (ER stress) and activating the PERK-eIF2α-ATF4 signaling pathway. Taken together, our results suggest that FOD is a potential anticancer drug targeting ER stress for the treatment of HCC.
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Doxorubicin (DOX), a broad-spectrum anti-tumor drug, has severe cardiotoxic side effects that limit its clinical application. Perillaldehyde (PAE) is the main component of volatile oil extracted from the stems and leaves of Herbaceous plant-perilla, which demonstrates antioxidant, anti-inflammatory, hypolipidemic, and other health functions. The present study aimed to explore the protective effect of perillaldehyde on DOX-induced cardiotoxicity in rats and to confirm its possible mechanism. The results showed that PAE could significantly improve cardiac function, alleviate myocardial fibrosis, and attenuate oxidative stress and inflammatory responses in DOX-induced cardiotoxicity in rats. Mechanistically, PAE could DOX-induced cardiotoxicity, which is related to its regulation of the PI3K/Akt signaling pathway and inhibition of NHE1 phosphorylation. Therefore, the finding demonstrates that perillaldehyde may be a promising cardioprotective agent for the prevention and treatment of cardiotoxicity caused by DOX.
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Cardiotoxicidad , Proteínas Proto-Oncogénicas c-akt , Ratas , Animales , Cardiotoxicidad/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-akt/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Doxorrubicina/efectos adversos , Estrés Oxidativo , Apoptosis , Miocitos Cardíacos/metabolismoRESUMEN
A triazine derivative containing nitrogen and silicon (SiN) was synthesized and the SiN hybrid aerogel was covered on the surface of bamboo fiber (BF). The modified BF was identified as MBF. The MBF and ammonium polyphosphate (APP) were used to regulate the flame retardancy and mechanical properties of polylactic acid (PLA). The PLA/BF composites were investigated using limiting oxygen index (LOI), UL-94 vertical combustion, cone calorimetry, thermogravimetric analysis linked with infrared spectra (TG-IR) etc. The char residue of MBF at 800 °C is as high as 43.5 % which is 200 % more than that of BF. Incorporating 9 wt% APP generates a PLA9 which displays the UL-94 V2 rating and a LOI value of 28.0 vol%. PLA9/MBF composites display the UL-94 V0 rating and increased LOI values while PLA9/BF composites obtain the UL-94 V2 rating and decreased LOI. The MBF reduces the release of flammable gases during combustion, enhances charring ability and decreases the thermal conductivity of composites. Besides, the tensile and impact strength of PLA9/20MBF is 20 % and 37 % more than that of PLA9/20BF due to stronger interfacial adhesion. This work provides a good method to regulate the flame retardancy and mechanical properties of PLA/BF composites.
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Compuestos de Amonio , Retardadores de Llama , Silicio , Nitrógeno , Retardadores de Llama/análisis , Microscopía Electrónica de Rastreo , Poliésteres/química , Polifosfatos/química , Compuestos de Amonio/química , Fibras de la DietaRESUMEN
In clinic, there is still no unified standard for the treatment of non-alcoholic fatty liver disease (NAFLD), and the development of effective novel drugs to alleviate NAFLD remains a challenge. This study aimed to explore the effect and mechanism of amorphous selenium nanodots (A SeNDs) in alleviating NAFLD. Model rats with NAFLD were induced by the high-fat diet (HFD). Histomorphology was used to observe liver tissue, automatic biochemical analyzer was used to analyze liver function indicators, and ELISA kit was used to detect the effect of A SeNDs on oxidative stress and inflammatory factors in NAFLD rats. The results exhibited that A SeNDs could reduce hepatocyte steatosis, liver index, blood lipid level, and transaminase level in NAFLD rats. Furthermore, A SeNDs could relieve the oxidative stress and inflammatory reaction and maintain liver tissue structure in NAFLD rats. Mechanistically, A SeNDs (0.3 mg/kg/day) inhibit the phosphorylation of JNK/p38 MAPK pathways after activating vascular endothelial growth factor receptor 1 (VEGFR1) in the liver of rats with NAFLD to allay oxidative stress and inflammatory response and improves hepatic structure and liver function. Therefore, it should be an important method to mitigate NAFLD by supplementing A SeNDs to normalize hepatic structure and liver function.
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Enfermedad del Hígado Graso no Alcohólico , Selenio , Animales , Dieta Alta en Grasa/efectos adversos , Lípidos , Hígado , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Fosforilación , Ratas , Selenio/metabolismo , Selenio/farmacología , Transducción de Señal/fisiología , Transaminasas/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismoRESUMEN
Silk fibroin has become a promising biomaterial owing to its remarkable mechanical property, biocompatibility, biodegradability, and sufficient supply. However, it is difficult to directly construct materials with other formats except for yarn, fabric and nonwoven based on natural silk. A promising bioinspired strategy is firstly extracting desired building blocks of silk, then reconstructing them into functional regenerated silk fibroin (RSF) materials with controllable formats and structures. This strategy could give it excellent processability and modifiability, thus well meet the diversified needs in biomedical applications. Recently, to engineer RSF materials with properties similar to or beyond the hierarchical structured natural silk, novel extraction and reconstruction strategies have been developed. In this review, we seek to describe varied building blocks of silk at different levels used in biomedical field and their effective extraction and reconstruction strategies. This review also present recent discoveries and research progresses on how these functional RSF biomaterials used in advanced biomedical applications, especially in the fields of cell-material interactions, soft tissue regeneration, and flexible bioelectronic devices. Finally, potential study and application for future opportunities, and current challenges for these bioinspired strategies and corresponding usage were also comprehensively discussed. In this way, it aims to provide valuable references for the design and modification of novel silk biomaterials, and further promote the high-quality-utilization of silk or other biopolymers.
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Dementia in Parkinson's disease (PD) has become a major factor affecting the quality of life of patients with Parkinson's disease. Early detection and timely prevention can delay the progression of dementia, improve the quality of life of patients, and reduce the burden on society. This article is aimed at studying how to analyze the efficacy of moxibustion in the treatment of Parkinson's disease through meta-analysis on the basis of smart medicine. This article puts forward the related conceptual knowledge of smart medicine and meta-analysis and moxibustion treatment and proposes a deep learning method based on smart medicine to analyze the effects of moxibustion treatment on patients. The experiment in this article can be seen from the data in one of the figures that the highest curative effect of using a single moxibustion to treat Parkinson's disease is about 46%, while the curative effect of using a combination of moxibustion and Western medicine has reached 90%. It can be seen that a single moxibustion is not as effective as a combination of the two for Parkinson's disease. From the data in one of the tables, it can be seen that the proportion of Parkinson's disease in 2016 was 15%, showing an increase of 5%. By 2020, the proportion of Parkinson's disease was as high as 38%, and the growth rate reached 9%. It can be seen that the prevalence of this disease is getting higher and higher. Parkinson's disease has caused many undesirable effects on patients, such as slow movement, mental disorders, and a decline in mental state. Therefore, it is urgent to study the treatment of Parkinson's disease. Moxibustion can improve the patient's blood circulation and help the patient's local limbs to recover more easily and can help improve the patient's motor function.
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Citronellal (CT) is an acyclic monoterpene aldehyde isolated from lemon citronella, which could ameliorate vascular endothelial dysfunction in atherosclerosis in our previous study, however, whether CT can alleviate vascular endothelial dysfunction related with type 2 diabetes (T2DM) is still unknown. So, we investigated the role of CT in vascular dysfunction related to T2DM and the mechanism involved. T2DM rat model was induced by a single intraperitoneal injection of low-dose streptozotocin (STZ) (60 mg/kg) to rats fed with high-fat diet (HFD) (4 weeks). After treated with CT (150 mg/kg/d), both the thoracic aorta injury and micro-vascular pathological injury in T2DM rats ex vivo were alleviated, and the oxidative stress in T2DM rats treated with CT were attenuated, manifested as increased content of endothelial nitric oxide synthase (eNOS) and superoxide dismutase (SOD), and decreased content of malondialdehyde (MDA). Furthermore, CT (15 µg/L) increased the migration capacity of human umbilical vein endothelial cells (HUVECs) under high glucose circumstance (30 mM), and increased the endothelial-dependent relaxation in thoracic aorta isolated from T2DM rats in vitro. Finally, all of these effects of CT were blocked by fingolimod (FTY720), a sphingosine-1-phosphate receptor agonist, and the expression of sphingosine-1-phosphate receptor 1 (S1P1) was increased by CT. In conclusion, CT improved vascular function through S1P/S1P1 signaling pathway.
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Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Monoterpenos Acíclicos , Aldehídos , Animales , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/metabolismo , Dieta Alta en Grasa/efectos adversos , Endotelio Vascular , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Humanos , Óxido Nítrico Sintasa de Tipo III/metabolismo , Ratas , Transducción de Señal , Estreptozocina/efectos adversosRESUMEN
BACKGROUND: Vascular cognitive dysfunction in patients with vascular dementia (VD) is a kind of severe cognitive dysfunction syndrome caused by cerebrovascular diseases. At present, effective drugs to improve the cognitive function of VD patients still need to be explored. Transient Receptor Potential Melastatin 2 (TRPM2) channel is a nonspecific cation channel that plays a key role in the toxic death of neurons. Perillaldehyde (PAE) has the protective effect of epilepsy and insomnia and other central nervous system diseases. The aim of this study is to explore whether PAE improves cognitive function in VD rats and to investigate the potential mechanisms in vivo and vitro. METHODS: VD rats were induced by bilateral common carotid arteries occlusion (2-vessel occlusion [2VO]) and treated with PAE for 4 weeks. The neuroprotective effects of PAE was subsequently assessed by the Morris water maze, hematoxylin-eosin (HE) staining, Golgi staining, electron microscopy, Neuron-specific nuclear protein (Neu N) staining, and TdT-mediated dUTP nick end labeling (TUNEL) staining. After primary hippocampal neurons were isolated, cell viability was detected by MTT assay and intracellular Ca2+ concentration was detected by calcium imaging assay. The content of Nitriteoxide (NO), Malondialdehyde (MDA) and Superoxide dismutase (SOD) activity in serum of rats were observed by Enzyme Linked Immunosorbent Assay (ELISA). Immunohistochemistry, Western blot, and Confocal laser scanning were used to detect the expression levels of N-methyl-D-asprtate receptor-2B (NR2B) and TRPM2. RESULTS: The results showed that PAE can improve the number and activity of neurons, increase the length and number of dendrites in hippocampus, decrease the Vv value and PE value of neuronal nucleus and mitochondrial structure significantly, increase the s value and L value in nucleus structure, decrease the s value and L value in mitochondrial structure, and improve the learning and memory ability of rats significantly. And PAE can strengthen the ability of antioxidant stress confirmed by increasing the activity of SOD and reducing the production of MDA. The results of western blot, immunohistochemistry and immunofluorescence showed that PAE could reduce the level of TRPM2 and increase the expression of NR2B. CONCLUSIONS: Taken together, our findings provide evidence that the neuroprotective effects of PAE in VD rats maybe through TRPM2 inhibition and subsequent activation of NMDAR signaling pathway.
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Monoterpenos Acíclicos/farmacología , Aldehídos/farmacología , Fármacos Cardiovasculares/farmacología , Cardiomiopatías Diabéticas/prevención & control , Monoterpenos Acíclicos/uso terapéutico , Aldehídos/uso terapéutico , Animales , Fármacos Cardiovasculares/uso terapéutico , Cardiomiopatías Diabéticas/complicaciones , Cardiomiopatías Diabéticas/metabolismo , Cardiomiopatías Diabéticas/patología , Fibrosis/metabolismo , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/prevención & control , Masculino , Ratas Sprague-Dawley , Receptor 1 de Factores de Crecimiento Endotelial Vascular/genética , Receptor 1 de Factores de Crecimiento Endotelial Vascular/metabolismo , Disfunción Ventricular Izquierda/complicaciones , Disfunción Ventricular Izquierda/metabolismo , Disfunción Ventricular Izquierda/patología , Disfunción Ventricular Izquierda/prevención & controlRESUMEN
In the present study we developed novel luminescent magnetic nanocomposites termed Fe3O4@polyaniline/carbon dots. First, Fe3O4 magnetic nanoparticles were prepared by the coprecipitation method. The nanoparticles were then coated with polyaniline using the in situ growth method to form Fe3O4@polyaniline nanohybrids, which were endowed with amino functional groups on the surface and avoided the aggregation of Fe3O4 nanoparticles. The X-ray diffraction pattern demonstrated that the crystalline phase of the Fe3O4 nanoparticles was an inverse spinel structure and was not changed in the Fe3O4@polyaniline nanohybrids. The saturation magnetization and the coercive force of the as-prepared Fe3O4@polyaniline nanohybrids measured by a vibrating sample magnetizer were 63.7 emu·g-1 and zero respectively, which indicated that the Fe3O4@polyaniline nanohybrids exhibited excellent superparamagnetism. The Fe3O4@polyaniline nanohybrids were conjugated with carbon dots, prepared from orange juice, via the amide bond between the amino groups on the surface of the Fe3O4@polyaniline nanohybrids and the carboxyl groups on the surface of carbon dots. The obtained luminescent magnetic nanocomposites Fe3O4@polyaniline/carbon dots showed good photoluminescent properties, which hinted that the nanocomposites have potential in drug tracing and magnetic targeted drug delivery. Finally, the anticancer drug methotrexate was loaded into the Fe3O4@polyaniline/carbon dots nanocomposites, forming a novel magnetic targeted drug delivery system. The results confirmed that the novel drug delivery system exhibited excellent drug-loading capability for methotrexate of ca. 70%, and emits strong fluorescence at the wavelength of 360 nm. An in vitro release experiment of the drug delivery system indicated that the cumulative release percentage of methotrexate was 17.2% in the phosphate-buffered saline (pH = 7.4) within 36 h.
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Metotrexato , Nanocompuestos , Compuestos de Anilina , Carbono , Fenómenos MagnéticosRESUMEN
This study presents a novel and effective method, i.e., adding nitrite into acidic fermentations after ultrasonic (US) pretreatment to form free nitrous acid (FNA), to further enhance hydrogen yield. Experimental results showed that when 180â¯mg/L nitrite was added into the US (2â¯W/mL, 15â¯min) pretreated waste activated sludge (WAS), the maximal hydrogen yield of 24.81⯱â¯1.24â¯mL/gâ¯VSS (volatile suspended solids) was obtained under acidic fermentation (1.0â¯mg/Lâ¯FNA was initially formed under this condition), which was 2.21-folds (or 1.36-folds) of that from US pretreatment (or FNA treatment) alone. This combination approach caused a positive synergy on sludge disintegration and enhanced the transformation of the released organics from non-biodegradable to biodegradable. Further study showed that the inhibiting effect of this combination method on hydrogen consuming microorganism was severer. Considering its pollution free, this combination strategy is an attractive technology for hydrogen recovery from WAS.
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Ácido Nitroso , Aguas del Alcantarillado , Fermentación , Hidrógeno , UltrasonidoRESUMEN
In this study, nascent silk nanoribbons (SNRs) with an average thickness of 0.4 nm were extracted from natural silkworm silk by partially dissolving degummed silk (DS) in sodium hydroxide (NaOH)/urea solution at -12 °C. In this gentle treatment, the solvent could not destroy the nanofibrillar structure completely, but the chosen conditions would influence the dimensions of resulting SNRs. Molecular dynamics simulations of silk models indicated that the potential of mean force required to break hydrogen bonds between silk fibroin chains was 40% larger than that of van der Waals interactions between ß-sheet layers, allowing the exfoliating treatment. It was found that the resulting SNRs contained a single ß-sheet layer and amorphous silk fibroin molecules, which could be considered as the basic building block of DS consisting of hierarchical structures. The demonstrated technique for extracting ultrathin SNRs having the height of a single ß-sheet layer may provide a useful pathway for creating stronger and tougher silk-based materials and/or adding functionality and durability in materials for various applications. The hierarchical structure model based on SNRs may afford more insight into the structure and property relationship of fabricating silk-based materials.
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CONTEXT: Temporal lobe epilepsy (TLE) is resistant to antiepileptic drugs (AEDs) and is associated with cognitive impairment. The modern Chinese medicine, compound Danshen dripping pills (CDDP), is clinically effective in treating epilepsy and improving cognitive impairment. OBJECTIVE: This study evaluated the protective effects of CDDP alone and in combination with carbamazepine (CBZ) on kainic acid-induced TLE and cognitive impairment in rats. MATERIALS AND METHODS: Sprague-Dawley rats were randomly divided into five groups: control (sham operated), model, CDDP, CBZ and combined. A TLE model was then created via bilateral intrahippocampal injection of 0.35 µg kainic acid (KA). Rats received CDDP (85 mg/kg), CBZ (100 mg/kg) or combined (85 mg/kg CDDP +100 mg/kg CBZ) via intragastric administration for 90 d, respectively. Seizure intensity, apoptosis and glial cell line-derived neurotrophic factor (GDNF) were measured. Furthermore, the improvement in cognitive impairment and hippocampal neuronal damage was evaluated. RESULTS: CDDP combined with CBZ significantly decreased seizure severity and frequency (p < 0.05) and ameliorated cognitive impairment (p < 0.05). The model group showed a significant reduction of neurons and Bcl-2/Bax expression in the hippocampus CA3 area (p < 0.01), the combined groups significantly reversed these change (p < 0.01). GDNF expression in the combined groups showed a clear increase over the model group (p < 0.05). CONCLUSION: These findings support the use of CDDP as an adjuvant drug for the treatment of TLE and cognitive deficit. Its mechanism might be related to an anti-apoptosis effect and up-regulation of GDNF.