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1.
Carbohydr Polym ; 224: 115147, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472826

RESUMO

Here, we designed a self-healing composite hydrogel with antioxidant and antibacterial activities by using cellulose nanofibrils (CNF) and tannic acid (TA) as functional additives. Excellent mechanical stability, moldability, stretchability and rapid self-healing ability without any external intervention were realized in one system due to the combined dynamic borate ester bonding between polyvinyl alcohol-borax (PB) and multi-hydrogen bonding between different components. The rheological measurements indicated the incorporation of CNF and TA to PB system substantially affected the viscoelasticity of hydrogels. The unique antioxidant and antibacterial properties were achieved due to the complexation of TA. These high performance multifunctional hydrogels opens a window for a broad application in the field of smart devices and surface engineering.

2.
Carbohydr Polym ; 224: 115197, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472838

RESUMO

In order to obtain new retention and drainage-aid agent, exfoliated xylan-g-QCS/MMT nanocomposites were prepared. Briefly, quaternized chitosan azide (QCS-N3) was intercalated into the layer of montmorillonite (MMT) to enlarge the interplanar gallery; subsequently, QCS-N3/MMT was grafted with xylan by click chemistry, during this process, the interlayer space of MMT was further increased till exfoliated. Subsequently, the exfoliated xylan-g-QCS/MMT was evaluated to act as retention and drainage-aid agent. The initial critical concentration of xylan-g-QCS/MMT was 0.01 mg/g in the adsorption behavior on cellulosic substrate. The maximum flocculation efficiency for CaCO3 was 37.41%. When dosages were about 0.01 mg/g, oSR values were the lowest. All these results show that retention and drainage-aid performance of xylan-g-QCS/MMT was better than only xylan, QCS or MMT. The study combined three kinds of natural resources to prepare organic/inorganic nanocomposites, providing a new method to develop papermaking additive and achieve high-value utilization of natural resources.

3.
Environ Int ; 132: 105127, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31487610

RESUMO

Although atmospheric microplastics have been found to be ubiquitous even on untraversed mountains and have potential impacts on human health, little information concerning their sampling methodology and transport is currently available. Until a realistic quantification of suspended atmospheric microplastics (SAMPs) is obtained, however, any potential health risk assessment for this pollutant will be open to criticism for using an ambiguous dataset. To address this knowledge gap, in May 2019 a trial experiment was performed to explore the potential relationship between sampling volume and SAMP abundance. A significant logarithmic regression between SAMP abundance and the sampling volume of filtrated air was found and the sufficient volume of filtrated air for accurate SAMP quantification was recommended. Investigation results indicated that fibrous and fragment-shaped SAMPs comprised 91% of all of the identified synthetic particles. Interestingly, for the first time, plastic microbeads were also observed in the collected air, constituting 9% of the all of the SAMPs by quantity. Spectral analysis revealed that these SAMPs consisted of polyethylene terephthalate (PET), epoxy resin (EP), polyethylene (PE), alkyd resin (ALK), rayon (RY), polypropylene (PP), polyamide (PA), and polystyrene (PS). PET, EP, PE, and ALK constituted the majority (90%) of all of the polymer types, with quantitative percentages of 51%, 19%, 12%, and 8%, respectively. Based on our numerical modeling simulation, the approximate transport flux of SAMPs during June in Shanghai was estimated, ranging from 9.94 × 104 n/(m·d) to 6.52 × 105 n/(m·d), with a mean of 3.00 ±â€¯1.58 × 105 n/(m·d). The goal of our study was to provide an essential methodological aid for the accurate determination of SAMPs in the environment and a better understanding of terrestrial microplastic transport in megacities.

4.
ACS Sens ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31402650

RESUMO

Ultraviolet (UV) photochromism is observed from natural light in amorphous TiO2 nanotube arrays (NTAs) for the first time. Surface color of the NTAs film would change from light yellow to dark brown eventually, either under ultraviolet bulb irradiation or basking under natural sunlight. This photochromism is attributed to the appearance of Ti3 + ions in the TiO2 NTAs after UV illumination. Furthermore, a UV radiation cumulative dosimeter is designed and fabricated, consisting of a photochromic film and a colorimetric card, which convert invisible ultraviolet rays into visible color changes. This device helps people to understand intuitively how much UV radiation has been received in total from surrounding environments, which is of great importance for skin safety and public health.

5.
Environ Sci Technol ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31408609

RESUMO

Although atmospheric transport and deposition could be an important pathway of terrestrial pollutants to the ocean, little information concerning the presence and distribution of these suspended atmospheric microplastics in marine air is available. We investigated, for the first time, the occurrence and distribution of suspended atmospheric microplastics (SAMPs) in the west Pacific Ocean. In this study, the spatial distribution, morphological appearance, and chemical composition of suspended atmospheric microplastics were studied through continuous sampling during a cruise. SAMPs abundance ranged from 0 to 1.37 n/m3, the median of 0.01 n/m3. Fiber, fragment, and granule SAMPs quantitively constituted 60%, 31%, and 8% of all MPs, respectively. Interestingly, plastic microbeads with numerical proportion of 5% were also observed. A high suspended atmospheric microplastics abundance was found in the coastal area (0.13 ± 0.24 n/m3), while there was less amount detected in the pelagic area (0.01 ± 0.01 n/m3). The amount of suspended atmospheric microplastics collected during the daytime (0.45 ± 0.46 n/m3) was twice the amount collected at night (0.22 ± 0.19 n/m3), on average. Our observations provide field-based evidence that suspended atmospheric microplastics are an important source of microplastics pollution in the ocean, especially the pollution caused by textile microfibers.

6.
Chem Biol Drug Des ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31452330

RESUMO

In this study, a peptide-drug conjugate was designed and synthesized by connecting a transferrin receptor (TfR) targeted binding peptide analog BP9a (CAHLHNRS) with doxorubicin (DOX) through N-succinimidyl-3-maleimidopropionate (SMP) as the cross-linker. Confocal laser scanning microscopy results indicated that free DOX mainly accumulated in the nuclei of both TfR overexpressed HepG2 hepatoma cells and L-O2 normal liver cells expressing low level of TfR; Most of the BP9a-DOX conjugate displayed cytoplasmic location, and its cellular uptake by HepG2 cells was obviously reduced by TfR blockage test. Nevertheless, the cellular uptake of this conjugate by L-O2 cells was much less than that of free DOX. Meanwhile, the BP9a-DOX conjugate exhibited lower in vitro antiproliferative activity against HepG2 cells than free DOX, but its cytotoxic effect on L-O2 cells was decreased compared with that of free DOX. These results suggest that BP9a could be applied as a potential TfR targeted peptide vector for selective drug delivery. This article is protected by copyright. All rights reserved.

7.
Clin Exp Rheumatol ; 37 Suppl 118(3): 209-216, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31376261

RESUMO

Sjögren's syndrome (SS) is a chronic autoimmune disease characterised by lymphocytic infiltration in exocrine glands with secretory dysfunction. Although both environmental triggers and genetic predisposition have been recognised as important factors in the initiation and development of SS, the pathogenesis of SS is complex and still largely unclear. Animal models have served as useful tools for studying SS pathogenesis with several advantages. A number of animal models recapitulating key characteristics of primary SS patients including secretory dysfunction, glandular inflammation and presence of autoantibodies were developed in the past years. The studies based on the animal models of SS have provided significant insight in SS pathogenesis and therapeutic intervention. This review summarises current animal models with primary SS-like symptoms including spontaneous models, genetically modified models, induced models and humanised models, and discusses their contribution to the understanding of SS aetiology and therapies.

8.
Gynecol Endocrinol ; : 1-5, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464150

RESUMO

The aim of this study was to evaluate the effect of granulocyte colony-stimulating factor (G-CSF) on thin endometrium (≤7 mm) in women undergoing frozen-thawed embryo transfer (FET). This retrospective cohort study includes 271 infertile patients with thin endometrium. 117 patients who received intrauterine perfusion of G-CSF before the day of administration of progesterone were defined as G-CSF group, whereas 154 patients who refused to use G-CSF treatment were defined as control group. In the G-CSF group, significantly higher endometrial thickness was observed after G-CSF perfusion (p < .001). When we divided the G-CSF group into two subgroups according to whether they conceived, the endometrial thickness increased from 6.02 ± 0.92 mm to 6.98 ± 1.20 mm in the conception group (p < .001) and from 6.21 ± 0.96 mm to 6.87 ± 1.16 mm in the non-conception group (p < .001). However, there were no significant differences between the two subgroups in respect to the endometrial thickness both before and after G-CSF perfusion. The implantation rate, hCG positive rate and clinical pregnancy rate were similar between G-CSF group and control group. Thus, our study fails to demonstrate that G-CSF has the potential to improve pregnancy outcome but has the potential to increase endometrial thickness of the women with thin endometrium in FET cycles.

9.
Artigo em Inglês | MEDLINE | ID: mdl-31433751

RESUMO

BACKGROUND AND AIMS: Secretory clusterin (sCLU) is a protein biosensor of oxidative stress and inflammation, which is involved in numerous physiological processes, such as carcinogenesis, tumor growth and tissue remodelling. sCLU is up-regulated in many cancers, which affects cell apoptosis and invasion. Overexpression of sCLU also confers treatment resistance to many varied anti-cancer therapies. Therefore sCLU could be an attractive target in cancer therapy. In the present study, we study the role of targeting sCLU using small interfering RNAs (siRNAs) on cell apoptosis, invasion and sensitivity to chemotherapy in human cancer in human osteosarcoma cells. METHODS: Expression of sCLU in 98 cases of osteosarcoma was detected by immunohistochemistry. The sCLU levels in 98 cases and clinical data and survival was compared. siRNA-mediated sCLU gene silencing on cell apoptosis, viability , invasion and chemosensitivity to doxorubicin in osteosarcoma cells were detected. RESULTS: sCLU expression was found in 59 (60%) of the 98 patients. A positive correlation was observed between sCLU expression and metastatic disease (P = 0.036) and a negative correlation between sCLU expression and response to chemotherapy (P = 0.002). Targeting sCLU expression in osteosarcoma cells induces significant reduction of cellular growth and higher rates of spontaneous endogenous apoptosis. In addition, targeting sCLU expression inhibits invasion of osteosarcoma cells. Furthermore, targeting sCLU expression significantly sensitized to chemotherapeutic drugs doxorubicin. CONCLUSIONS: Overexpression of sCLU was significantly correlated with metastasis and chemosensitivity in osteosarcoma cells. The described sCLU-specific siRNA that can potently silence sCLU gene expression may thus prove valuable agents during antitumor therapy.

10.
Mar Pollut Bull ; 146: 173-182, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31426144

RESUMO

Plastic pollution, including microplastics (MPs), poses a global threat to environmental and human health. Studies on the transference of MPs along marine food webs are limited. In the present study, we investigated MP pollution in 11 wild fish species (193 individuals) and 8 wild crustacean species (136 individuals) captured from the Zhoushan fishing ground, off the East China Sea. The average abundance of MPs found in two main tissues, the gill and gastrointestinal (GI) tract, were 0.77 ±â€¯1.25 and 0.52 ±â€¯0.90 items/individual, respectively. The MPs we found were predominantly fiber-shaped, blue, and composed of polyester polymers. Our results suggest that MP pollution is ubiquitous in the East China Sea. We suggest that MPs are likely aggregated in the higher trophic level fish species throughout the marine food web. Furthermore, we suggest that marine organisms which occupy higher trophic levels might be suitable MP indicator species.

11.
Proc Natl Acad Sci U S A ; 116(35): 17213-17218, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31405985

RESUMO

Two-dimensional monolayer materials, with thicknesses of up to several atoms, can be obtained from almost every layer-structured material. It is believed that the catalogs of known 2D materials are almost complete, with fewer new graphene-like materials being discovered. Here, we report 2D graphene-like monolayers from monoxides such as BeO, MgO, CaO, SrO, BaO, and rock-salt structured monochlorides such as LiCl, and NaCl using first-principle calculations. Two-dimensional materials containing d-orbital atoms such as HfO, CdO, and AgCl are predicted. Adopting the same strategy, 2D graphene-like monolayers from mononitrides such as scandium nitride (ScN) and monoselenides such as cadmium selenide (CdSe) are discovered. Stress engineering is found to help stabilize 2D monolayers, through canceling the imaginary frequency of phonon dispersion relation. These 2D monolayers show high dynamic, thermal, kinetic, and mechanic stabilities due to atomic hybridization, and electronic delocalization.

12.
Xenobiotica ; : 1-11, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31424332

RESUMO

Polygonum multiflorum Thunb. (PM) is a famous traditional Chinese medicine with liver tonic effect, but arousing great concerns for hepatotoxicity issue. In this study, we elucidated the contribution of the two major compounds, emodin-8-O-ß-D-glucoside (EG) and 2,3,5,4´-tetrahydroxyl diphenylethylene-2-O-glucoside (TSG), in PM-induced liver injury. Based on LC-MS, the two concerned compounds were detected simultaneously in the sera of patients with PM-induced liver injury. In the lipopolysaccharide (LPS)-mediated inflammatory stress rat model, by the analysis of plasma biochemistry and liver histopathology, we observed that the solo treatment of EG, not TSG, could induce significant liver injury; and the combined administration of EG and TSG caused more severe liver injury than that of EG. Metabolomics analysis revealed that the EG-triggered liver injury was associated with significant disturbances of sphingolipids and primary bile acids metabolism pathways. In the combined administration group, much more disturbances in EG-triggered metabolic pathways, as well as alterations of several additional pathways such as retinol metabolism and vitamin B6 metabolism, were observed. Taken together, we considered EG was involved in the idiosyncratic liver injury of PM, and TSG played a synergetic role with EG, which contributed to the understanding of the hepatotoxic basis of PM.

13.
Environ Technol ; : 1-12, 2019 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-31446846

RESUMO

The purpose of this study was to investigate the effects of increasing salinity on the performance and microbial community structure in a sequencing batch reactor (SBR) treating low C/N ratio wastewater. The SBR was subjected to a gradual increased salinity from 0 wt% to3.0 wt% under low Chemical Oxygen Demand (COD)/N ratio, operating for 80 days. The study results indicated that high salinity decreased the removal efficiency of ammonium ( NH4+-N ) from 77.09% (1.0 wt%) to 45.7% (3.0wt%). The organic matter removal are not significantly affected by the high salinity. Non-metric Multi-Dimensional Scaling (NMDS) analysis showed that the gradual increased salinity altered the overall bacterial community structure, and low salinity (1wt%) promoted the bacterial diversity, while high salinity (2 and 3 wt%) significantly decreased the bacterial diversity in low C/N ratio activated sludge system. Further analysis revealed that two genera related to nitrification process (unclassified-Nitrosomonadales and g-Nitrospira) were inhibited, while a genus related to organic removal (Piscicoccus) and three genera related to denitrification (Rodobacteraceae, Denitromonas and Hyphomicrobium) increased significantly at a salinity of 3 wt%. This study provides insights of shifts in the bacteria community under the stress of high salinity in low C/N ratio of activated sludge systems.

14.
CNS Neurosci Ther ; 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31411808

RESUMO

INTRODUCTION: The occurrence of circadian rhythm disorder in patients with Alzheimer's disease (AD) is closely related to the abnormal deposition of amyloid-ß (Aß), and d-Ser2-oxyntomodulin (Oxy) is a protease-resistant oxyntomodulin analogue that has been shown to exert neuroprotective effects. AIMS: This study aimed to explore whether Oxy, a new GLP-1R/GCGR dual receptor agonist, can improve the Aß-induced disrupted circadian rhythm and the role of GLP-1R. METHODS: A mouse wheel-running experiment was performed to explore the circadian rhythm, and western blotting and real-time PCR were performed to assess the expression of the circadian clock genes Bmal1 and Per2. Furthermore, a lentivirus encoding an shGLP-1R-GFP-PURO was used to interfere with GLP-1R gene expression and so explore the role of GLP-1R. RESULTS: The present study has confirmed that Oxy could restore Aß31-35-induced circadian rhythm disorders and improve the abnormal expression of Bmal1 and Per2. After interfering the GLP-1R gene, we found that Oxy could not improve the Aß31-35-induced circadian rhythm disorder and abnormal expression of clock genes. CONCLUSION: This study demonstrated that Oxy could improve Aß31-35-induced circadian rhythm disorders, and GLP-1R plays a critical role. This study thus describes a novel target that may be potentially used in the treatment of AD.

15.
Int Immunopharmacol ; 75: 105833, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31450152

RESUMO

Hepatic fibrosis is a reversible would-healing response following chronic liver injury of different aetiologies and represents a major worldwide health problem. Up to date, there is no satisfactory drugs treated for liver fibrosis. The present study was to investigate hepatoprotection of yangonin against liver fibrosis induced by thioacetamide (TAA) in mice and further to clarify the involvement of farnesoid X receptor (FXR) in vivo and in vitro. Yangonin treatment remarkably ameliorated TAA-induced liver injury by reducing relative liver weight, as well as serum ALT and AST activities. Moreover, yangonin alleviated TAA-induced accumulation of bile acids through increasing the expression of bile acid efflux transporters such as Bsep and Mrp2, and reducing hepatic uptake transporter Ntcp expression, all of these are FXR-target genes. The liver sections stained by H&E indicated that the histopathological change induced by TAA was improved by yangonin. Masson and Sirius red staining indicated the obvious anti-fibrotic effect of yangonin. The mechanism of anti-fibrotic effect of yangonin was that yangonin reduced collagen content by regulating the genes involved in hepatic fibrosis including COL1-α1 and TIMP-1. Besides, yangonin inhibited hepatic stellate cell activation by reducing TGF-ß1 and α-SMA expression. In addition, yangonin protected against TAA-induced hepatic inflammation via its inhibition of NF-κB and TNF-α. These hepatoprotective effects of yangonin were abrogated by guggulsterone which is a FXR antagonist. In vitro experiment further demonstrated dose-dependent activation of FXR by yangonin using dual-luciferase reporter assay. In summary, yangonin produces hepatoprotection against TAA-induced liver fibrosis via FXR activation.

16.
Molecules ; 24(15)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390736

RESUMO

Four new lignan glycosides; urenalignosides A-D (1-4), along with 12 known ones (5-16) were isolated from Urena lobata. Their structures were determined on the basis of extensive spectroscopic and spectrometric data (1D and 2D NMR; IR; CD; and HRESIMS). Compounds 2-4; 6; 7; 10; and 11 showed inhibition of nitric oxide production in lipopolysaccharide-induced RAW 264.7 macrophage cells with IC50 values in the range of 25.5-98.4 µM (positive control; quercetin; IC50 = 7.2 ± 0.2 µM).

17.
Medicine (Baltimore) ; 98(32): e16592, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31393358

RESUMO

RATIONALE: Refractory nasopharyngeal carcinoma is challenging to treat and at present there is no standard treatment or any good choice. PATIENT CONCERNS: Although the three patients in our case reports had already underwent multiple treatments before, they still suffered from disease recurrence of nasopharyngeal carcinoma. DIAGNOSIS: They were diagnosed as refractory nasopharyngeal carcinoma. INTERVENTIONS: A continuous infusion of Endostar, an antiangiogenic agent, combined with chemotherapy and radiation therapy was given to treat the patients. OUTCOMES: Patients showed complete or partial response to the combined therapy as evidenced by regression of tumors and decrease in plasma Epstein-Barr virus (EBV) DNA load. LESSONS: Continuous infusions of Endostar in combination with chemotherapy and/or radiation therapy showed promising efficacy and safety. The combination therapy indicates a new approach to treat refractory nasopharyngeal carcinoma.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Endostatinas/uso terapêutico , Carcinoma Nasofaríngeo/tratamento farmacológico , Neoplasias Nasofaríngeas/tratamento farmacológico , Proteínas Recombinantes/uso terapêutico , Adulto , Quimiorradioterapia/métodos , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo/terapia , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia
18.
ACS Nano ; 13(8): 8854-8864, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31322335

RESUMO

The development of silicon-based anode materials is important for improving the energy density of current lithium ion batteries. However, there are still strong demands for these materials with better cycle stability and higher reversible capacity. Here, a kind of dual bond restricted MXene-Si-CNT composite anode materials with enhanced electrochemical performance is reported. These dual bonds have been clearly revealed by an X-ray photoelectron spectroscopy technique and also proven by theoretical calculations with spontaneous reaction energy values (-0.190 and -0.429 eV/atom for Ti-Si and C-Si bonds, respectively). The cycle stability of the composites, prepared by a facile ball-milling synthetic method, can obviously be improved because of the existence of these dual bonds and the multidimensional constructed architecture. The MXene-Si-CNT composite with 60 wt % silicon possesses the best overall performance, with ∼80% capacity retention after 200 cycles, and achieves 841 mAh g-1 at 2 A g-1. This approach demonstrates a promising strategy to exploit high-performance anode materials and lessens the immanent negative effect of silicon-based materials. Furthermore, it is significant to extend this method to other anode materials with serious volumetric change problems during the cycling process.

19.
Biosens Bioelectron ; 142: 111518, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326861

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative illness that affects the elderly population worldwide. The definite diagnosis of AD still depends on post-mortem pathological examination of amyloid plaques consisting of amyliod-ß peptides (Aß) fibrils in the brain so far. However, these fibrils are not closely linked to the development of the disease. Alternatively, soluble Aß are believed to be more reliable biomarkers for early diagnosis of AD. Here, we report a simple approach to quantitative detection of soluble Aß species using N-(6-(benzothiazol-2-yl)pyridin-3-yl)-5-(dimethylamino)naphthalene-1-sulfonamide (BPNS) as a ratiometric fluorescence Zn2+ probe. This ratiometric fluorescence assay is based on the competition of soluble Aß with BPNS for Zn2+, that is, soluble Aß species with higher chelation affinity can capture Zn2+ from BPNS‒Zn2+ adduct, thereby reactivating the ratiometric fluorescence response of BPNS. BPNS exhibited perfect linear relationship (R2 = 0.998) in accordance with the concentration of soluble Aß in the presence of Zn2+. The assay possesses strong anti-interference capacity against exogenous agent or the other proteins, thanks to the high selectivity for soluble Aß species. Importantly, this assay can quantitatively detect soluble Aß species from different types of biological fluids, such as artificial cerebrospinal fluid (ACSF), serum, and plasma in half an hour. This assay provides a low-cost, fast, sensitive, and simple approach for quantitative detection of soluble Aß species and may serve as a potential tool for early-stage AD diagnosis.

20.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(3): 199-203, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31257798

RESUMO

OBJECTIVE: To analyze the expression and relationship of hypoxia-inducible factor-1α (HIF-1α), vascular endothelial growth factor (VEGF) and kinase insert domain receptor (KDR) in local skin tissues of pressure injury and investigate the possible mechanism of stage 3 pressure injury refractory wound. METHODS: Forty male SD rats were randomly divided into normal control group, compressed 3 d, 5 d, 7 d, and 9 d groups. Stage 3 pressure injury animal model were established by magnet compression. The morphology of skin was observed by HE staining. The expression of VEGF was detected by immunohistochemistry. The expression levels of HIF-1α, VEGF and KDR protein in skin tissue were detected by Western blot. One-way analysis of variance and LSD test were performed on the data. RESULTS: ①The HE results showed that compared with the normal control group, the epidermis of the compressed group was gradually thickened, the number of blood vessels was decreased, the collagen arrangement disordered and inflammatory cells infiltration were increased. ②Immunohistochemical results showed that the expression of VEGF protein in the 3 d group was significantly higher than that in the normal control group (P<0.01). The expression of VEGF protein in the skin tissue of 5 d, 7 d and 9 d groups was lower than that in normal control group (P<0.05). WB results were consistent with immunohistochemistry results. ③WB results showed that the expression of HIF-1α in the skin tissues of the rats in 3 d, 5 d and 7 d groups was higher than that in the normal control group (P<0.01 or P<0.05). The expression of KDR protein was lower than that of the normal control group (P<0.05 or P<0.01). CONCLUSION: HIF-1α mediated reduction of VEGF and KDR protein expression and decreased tissue angiogenesis may be one of the important causes of chronic dysfunction of stage 3 pressure injury.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Pressão/efeitos adversos , Pele/lesões , Fator A de Crescimento do Endotélio Vascular/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
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