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1.
Curr Med Imaging ; 20: 1-14, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389368

RESUMO

BACKGROUND: Magnetic resonance imaging (MRI) is a handy diagnostic tool for orthopedic disorders, particularly spinal and joint diseases. METHODS: The lumbar intervertebral disc is visible in the T1 and T2 weight sequences of the spine MRI, which aids in diagnosing lumbar disc herniation, lumbar spine tuberculosis, lumbar spine tumors, and other conditions. The lumbar intervertebral disc cannot be seen accurately in the Spectral Attenuated Inversion Recovery (SPAIR) due to weaknesses in the fat and frequency offset parameters, which is not conducive to developing the intelligence diagnosis model of medical image. RESULTS: In order to solve this problem, we propose a composite framework, which is first to use the contrast limited adaptive histogram equalization (CLAHE) method to enhance the SPAIR image contrast of the spine MRI and then use the non-local means method to remove the noise of the image to ensure that the image contrast is uniform without losing details. We employ the Information Entropy (IE), Peak signal-to-noise ratio (PSNR), and feature similarity index measure (FSIM) to quantify image quality after enhancement by the composite framework. CONCLUSION: The outcomes of the experiments' output images and quantitative data indicate that our composite framework is better than others.


Assuntos
Aumento da Imagem , Imageamento por Ressonância Magnética , Humanos , Aumento da Imagem/métodos , Imageamento por Ressonância Magnética/métodos , Razão Sinal-Ruído , Vértebras Lombares/diagnóstico por imagem
2.
Plast Reconstr Surg ; 153(2): 348e-360e, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-37171265

RESUMO

BACKGROUND: Adipose tissue engineering plays a key role in the reconstruction of soft-tissue defects. The acellular adipose matrix (AAM) is a promising biomaterial for the construction of engineered adipose tissue. However, AAM lacks sufficient adipoinduction potency because of the abundant loss of matrix-bound adipokines during decellularization. METHODS: An adipose-derived extracellular matrix collagen scaffold, "adipose collagen fragment" (ACF), was prepared using a novel mechanical method that provides sustained release of adipokines. Here, the authors used label-free proteomics methods to detect the protein components in AAM and ACF. In vivo, ACF was incorporated into AAM or acellular dermal matrix and implanted into nude mice to evaluate adipogenesis. Neoadipocytes, neovessels, and corresponding gene expression were evaluated. The effects of ACF on adipogenic differentiation of human adipose-derived stem cells and tube formation by human umbilical vein endothelial cells were tested in vitro. RESULTS: Proteomics analysis showed that ACF contains diverse adipogenic and angiogenic proteins. ACF can release diverse adipokines and induce highly vascularized, mature adipose tissue in AAM, and even in nonadipogenic acellular dermal matrix. Higher expression of adipogenic markers peroxisome proliferator-activated receptor gamma and CCAAT/enhancer-binding protein alpha and greater numbers of tubule structures were observed in ACF-treated groups in vitro. CONCLUSION: The combination of ACF and AAM could serve as a novel and promising strategy to construct mature, vascularized adipose tissue for soft-tissue reconstruction. CLINICAL RELEVANCE STATEMENT: The combined use of AAM and ACF has been proven to induce a highly vascularized, mature, engineered adipose tissue in the nude mouse model, which may serve as a promising strategy for soft-tissue reconstruction.


Assuntos
Tecido Adiposo , Engenharia Tecidual , Camundongos , Animais , Humanos , Engenharia Tecidual/métodos , Camundongos Nus , Preparações de Ação Retardada/metabolismo , Matriz Extracelular/metabolismo , Colágeno/metabolismo , Células Endoteliais da Veia Umbilical Humana , Alicerces Teciduais/química
3.
Front Pharmacol ; 14: 1288697, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38035018

RESUMO

Aim of the Study: Brachial plexus block (BPB) is widely used for patients undergoing upper limb surgeries. Ropivacaine is the most commonly used local anesthetic for BPB. This study aimed to identify the optimal ropivacaine concentration for BPB in adult patients undergoing upper limb surgeries. Materials and Methods: PubMed, Embase, the Cochrane Library, and Web of Science were searched to identify randomized controlled trials (RCTs) that compared the effects of different concentrations of ropivacaine for BPB in adult patients undergoing upper limb surgeries. The primary outcomes were the onset time of sensory and motor block. RevMan 5.4 software was used for analysis. The GRADE approach was used to assess evidence quality. Results: Nine studies involving 504 patients were included. Compared to 0.5% ropivacaine, 0.75% ropivacaine shortened the onset time of sensory (WMD, -2.54; 95% CI; -4.84 to -0.24; <0.0001, moderate quality of evidence) and motor blockade (WMD, -2.46; 95% CI, -4.26 to -0.66; p = 0.01; moderate quality of evidence). However, 0.5% and 0.75% ropivacaine provided similar duration time of sensory (WMD, -0.07; 95% CI, -0.88 to 0.74; p = 0.81; high quality of evidence) and motor blockade (WMD, -0.24; 95% CI, -1.12 to 0.65; p = 0.55; high quality of evidence), as well as time to first request for oral analgesia (WMD, -1.57; 95% CI, -3.14 to 0.01; p = 0.5; moderate quality of evidence). Conclusion: Moderate-quality evidence suggested that, in terms of the onset time of sensory and motor blockade, 0.75% ropivacaine is a preferred concentration for BPB in upper limb surgeries. Systematic Review Registration: identifier CRD42023392145.

4.
Polymers (Basel) ; 15(3)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36772004

RESUMO

Eco-gelled coal gangue materials (EGCGMs) are usually produced using coal gangue, slag, and fly ash in a highly alkaline environment. Herein, to improve the mechanical properties of such materials, polypropylene fibers were uniformly mixed with them. An unconfined compressive strength test and a three-point bending test of the fiber-reinforced EGCGMs under different conditions were conducted. Based on the performance degradation control technology of the fiber structure, the interface mechanism of the composite materials was analyzed from the micro level using scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). In the mechanical test, the 28 d UCS and flexural properties of the fiber-reinforced EGCGMs were analyzed using the Box-Behnken design response surface design method and orthogonal design method, respectively. The order of significance was as follows: sodium hydroxide, fiber length, and fiber content. Within the scope of the experimental study, when the NaOH content is 3, the fiber content is 5 ‱, and the fiber length is 9 mm, the mechanical properties are the best. Based on the microscopic equipment, it was discovered that the amorphous ecological glue condensation product formed by the reaction of slag and fly ash in the alkaline environment was filled between the coal gangue particles and the fibers, and several polymerization products accumulated to form a honeycomb network topology. The distribution of fibers in the EGCGM matrix could be primarily divided into single embedded and network occurrences. The fiber inhibits the crack initiation and development of the matrix through the crack resistance effect, and improves the brittleness characteristics through the bridging effect during the failure process, which promotes the ductility of the ecological cementitious coal gangue matrix.The results presented herein can provide a theoretical basis for improving the mechanical properties of alkali-activated geopolymers.

5.
Aesthet Surg J ; 42(5): NP337-NP350, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-36413201

RESUMO

BACKGROUND: Skin filler is an option for treating skin aging and wrinkles; however, currently used fillers are limited by poor biocompatibility, rapid degradation, and possible hypersensitivity reactions. Autologous adipose tissue-derived products have been recognized as promising options for skin rejuvenation. OBJECTIVES: This study aimed to develop a novel adipose-derived product for skin filling. METHODS: Adipose collagen fragment (ACF) was prepared through pulverization, filtration, and centrifugation. The macrography, structure, types of collagen, and cell viability of ACF were evaluated by immunostaining, western blotting, and cell culture assays. ACF, nanofat, and phosphate-buffered saline (9 spots/side, 0.01 mL/spot) were intradermally injected in the dorsal skin of 36 female BALB/c nude mice; the skin filling capacity and the collagen remodeling process were then investigated. Twenty-one female patients with fine rhytides in the infraorbital areas were enrolled and received clinical applications of ACF treatment. Therapeutic effects and patients' satisfaction scores were recorded. RESULTS: The mean [standard deviation] yield of ACF from 50 mL of Coleman fat was 4.91 [0.25] mL. ACF contained nonviable cells and high levels of collagen I, collagen IV, and laminin. Fibroblasts and procollagen significantly increased in ACF and ACF-treated dermis (P < 0.05). Overall, 85.7% of patients were satisfied with the therapy results, and no infections, injection site nodules, or other unwanted side effects were observed. CONCLUSIONS: ACF significantly improved dermal thickness and collagen synthesis and may serve as a potential autologous skin filler.


Assuntos
Preenchedores Dérmicos , Camundongos , Animais , Feminino , Camundongos Nus , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Tecido Adiposo
6.
FASEB J ; 36(10): e22550, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36098482

RESUMO

Clinical unpredictability and variability following fat grafting remain non-negligible problems due to the unknown mechanism of grafted fat retention. The role of the extracellular matrix (ECM), which renders cells with structural and biochemical support, has been ignored. This study aimed to clarify the ECM remodeling process, related cellular events, and the spatiotemporal relationship between ECM remodeling and adipocyte survival and adipogenesis after fat grafting. Labeled Coleman fat by the matrix-tracing technique was grafted in nude mice. The ECM remodeling process and cellular events were assessed in vivo. The related cytokines were evaluated by qRT-PCR. An in vitro cell migration assay was performed to verify the chemotactic effect of M2-like macrophages on fibroblasts. The results demonstrated that in the periphery, most of the adipocytes of the graft survived or regenerated, and the graft-derived ECM was gradually replaced by the newly-formed ECM. In the central parts, most adipocytes in the grafts died shortly after, and a small part of the graft-derived and newly-formed ECM was expressed with irregular morphology. Adipose ECM remodeling is associated with increased infiltration of macrophages and fibroblasts, as well as up-regulated expression of cytokines in the adipose tissue. To sum up, our results describe the various preservation mode of fat grafts after transplantation and underscore the importance of macrophage-mediated ECM remodeling in graft preservation after fat grafting. The appreciation and manipulation of underlying mechanisms that are operant in this setting stand to explore new therapeutic approaches and improve clinical outcomes of fat grafting.


Assuntos
Tecido Adiposo , Matriz Extracelular , Animais , Citocinas , Macrófagos , Camundongos , Camundongos Nus
7.
Biomater Adv ; 135: 212744, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35929203

RESUMO

Skin photoaging is one of the most serious public health problems in the 21st century that may lead to thin, saggy, and structurally weakened skin. Adipokine therapy toward skin photoaging is always associated with poor permeability, biologic stability and the short in vivo release duration. Our laboratory previously extracted an extracellular matrix component of adipose tissue by purely physical methods, namely "adipose collagen fragment (ACF)", which holds promise for preventing skin photoaging. However, the injection treatment of ACF requires repeated preparation processes and injection procedures, which may be time-consuming and painful. Therefore, we describe the fabrication and assessment of a detachable ACF-microneedle (ACF-MN) patch that creates minimally invasive dermal microtrauma upon application. And we evaluated the morphology characterization, mechanical properties and puncture performance in vitro. The delivery efficiency of ACF from the patches was estimated in vitro and vivo. Then, the therapeutic efficacy was identified through applying ACF-MN patches into the dermis of UVA-induced photoaging mice and the related detection of skin photoaging was estimated. Our results demonstrated that ACF-MN exhibited well skin puncture performance and could release ACF component slowly. Meanwhile, this microneedle device loaded with ACF exhibited the treatment efficiency on skin photoaging in a mouse model. Therefore, implantation of the microtrauma-mediated, long-acting ACF-MN system can be utilized as a potential candidate for preventing skin photoaging in the clinic.


Assuntos
Colágeno , Envelhecimento da Pele , Tecido Adiposo , Animais , Colágeno/administração & dosagem , Agulhamento Seco , Camundongos , Pele , Raios Ultravioleta/efeitos adversos
8.
Immunopharmacol Immunotoxicol ; 44(5): 757-765, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35616237

RESUMO

BACKGROUND: Fentanyl is an analgesic used against pancreatitis-related pain, while whether it ameliorates severe acute pancreatitis (SAP) has yet to be checked. This study aims to determine fentanyl-delivered effect on SAP and the mechanism underlying this effect. METHODS: Rat SAP models were established, following fentanyl treatment. The serum activity of amylase (AMY), lipase (LIP), and diamine oxidase (DAO) was detected by enzyme-linked immunosorbent assay (ELISA). Histological examination was performed in the pancreatic and intestinal tissues with hematoxylin-eosin staining. After transfection with matrix metalloproteinase (MMP) 9 overexpression plasmids, Caco-2 monolayers were treated with fentanyl and subsequently exposed to lipopolysaccharide (LPS). The transepithelial electrical resistance (TEER) value was determined in rat intestinal mucosa through an Ussing chamber assisted by Analyze & Acquire, and in Caco-2 cell monolayers through a voltohmmeter. Intestinal mucosa and paracellular permeabilities were determined by fluorescein isothiocyanate (FITC)-labeled dextran assay. The expressions of ZO-1, Occludin, MMP9, Fas and Fas ligand (FasL) in rat intestinal mucosa and/or Caco-2 monolayers were analyzed by qRT-PCR or/and western blot. RESULTS: Fentanyl alleviated SAP-related histological alterations in the pancreas and intestines, reduced the elevated levels of SAP-related AMY, LIP, and DAO, but promoted the levels of ZO-1 and Occludin. In SAP rats and Caco-2 monolayers, SAP-related or LPS-induced TEER value decreases, permeability increases, and increases in the expressions of MMP9, Fas, and FasL were reversed partly by fentanyl. Notably, MMP9 overexpression could reverse the above fentanyl-delivered in vitro effects. CONCLUSIONS: Fentanyl alleviates intestinal mucosal barrier damage in rats with SAP by inhibiting the MMP9/FasL/Fas pathway.


Assuntos
Amina Oxidase (contendo Cobre) , Pancreatite , Doença Aguda , Amina Oxidase (contendo Cobre)/metabolismo , Amina Oxidase (contendo Cobre)/farmacologia , Amilases/metabolismo , Animais , Células CACO-2 , Dextranos/metabolismo , Amarelo de Eosina-(YS)/metabolismo , Proteína Ligante Fas/metabolismo , Fentanila/metabolismo , Fluoresceína-5-Isotiocianato/análogos & derivados , Fluoresceína-5-Isotiocianato/metabolismo , Hematoxilina/metabolismo , Hematoxilina/farmacologia , Humanos , Mucosa Intestinal , Lipase/metabolismo , Lipopolissacarídeos/farmacologia , Metaloproteinase 9 da Matriz , Ocludina/metabolismo , Ocludina/farmacologia , Pancreatite/induzido quimicamente , Pancreatite/tratamento farmacológico , Pancreatite/metabolismo , Ratos
9.
Pflugers Arch ; 474(3): 343-353, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34989875

RESUMO

Although miR-10b-3p has been identified to be involved in cerebral ischemia injury, its impact and specific mechanism in cerebral ischemia injury remain unclear. The effects of Mir-10b-3p were investigated by establishing rat and cell models of ischemia/reperfusion (I/R) injury. Oxygen-glucose deprivation/reperfusion (OGD/R) was performed on pheochromocytoma-12 (PC12) cells. MiR-10b-3p expression levels in brain tissues and PC12 cells were detected by qRT-PCR. The impacts of miR-10b-3p on neurological deficits, infarct volume, inflammatory factor expression, in vivo brain water content, cell viability, and cell apoptosis were assessed. The relationship between miR-10b-3p and KLF5 was determined by TargetScan and luciferase reporter assay. The rescue experiments were performed to confirm the role of this axis in cerebral ischemia injury. Mir-10b-3p levels in rat brain tissue and PC12 cells were significantly decreased after I/R injury. MiR-10b-3p overexpression obviously reduced neurological deficits, infarct volume, brain water content, inflammatory factors expression, and neuronal apoptosis in the brain of ischemia-stroked rats. Meanwhile, miR-10b-3p upregulation also inhibited cell viability and apoptosis of OGD/R-induced PC12 cells. Besides, KLF5 was identified as a target of miR-10b-3p, and rescue experiments revealed that KLF5 was involved in the regulation of miR-10b-3p in ischemic injury. Our results demonstrated that miR-10b-3p had the neuroprotective effects against ischemia injury by targeting KLF5 and provided a potential underlying target for ischemic stroke treatment.


Assuntos
Isquemia Encefálica , MicroRNAs , Traumatismo por Reperfusão , Animais , Apoptose , Isquemia Encefálica/genética , Isquemia Encefálica/metabolismo , Infarto , Isquemia , Fatores de Transcrição Kruppel-Like/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Água
10.
J Surg Res ; 271: 171-179, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34815074

RESUMO

BACKGROUND: Myocardial injury induced by sepsis is the most common cause of death. Topiroxostat has been found to have organ protective effects, but its role in septic shock-related cardiomyocyte damage is still unclear and needs further study. MATERIAL AND METHODS: An endotoxemic shock model in rats was constructed. After topiroxostat treatment, hemodynamic parameters, myocardial injury marker enzymes, oxidative stress, myocardial injury, and apoptosis were measured by polyphysiograph, enzyme-linked immunosorbent assay, hematoxylin and eosin staining, TUNEL staining, and western blot. During in vitro experiments, the effect of topiroxostat on cell vitality, oxidative stress, inflammatory factors, apoptosis-related markers, phosphorylated-p65 (p-p65) and p65 expressions were measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, and western blot. RESULTS: Topiroxostat improved myocardial dysfunction and superoxide dismutase activity while suppressing levels of creatine kinase, lactate dehydrogenase and malondialdehyde in serum of endotoxemic shock rats. Additionally, topiroxostat augmented dry-wet weight ratios of the hearts in rats. Meanwhile, topiroxostat was proved to alleviate interstitial edema and apoptosis in myocardial tissues of endotoxemic shock rats. During in vitro experiments, topiroxostat pretreatment elevated lipopolysaccharide (LPS)-induced H9c2 cell vitality, and alleviated oxidative stress and inflammation. Moreover, topiroxostat pretreatment downregulated apoptosis-related markers, p-p65, and p-p65/p65 levels in LPS-induced H9c2 cells. CONCLUSIONS: Topiroxostat attenuated LPS-induced myocardial injury via repressing apoptosis and oxidative stress.


Assuntos
Lipopolissacarídeos , Nitrilas , Animais , Apoptose , Lipopolissacarídeos/farmacologia , Nitrilas/farmacologia , Estresse Oxidativo , Piridinas/farmacologia , Piridinas/uso terapêutico , Ratos
11.
Aesthet Surg J ; 42(5): NP337-NP350, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-34849564

RESUMO

BACKGROUND: Skin filler is an option for treating skin aging and wrinkles; however, currently used fillers are limited by poor biocompatibility, rapid degradation, and possible hypersensitivity reactions. Autologous adipose tissue-derived products have been recognized as promising options for skin rejuvenation. OBJECTIVES: This study aimed to develop a novel adipose-derived product for skin filling. METHODS: Adipose collagen fragment (ACF) was prepared through pulverization, filtration, and centrifugation. The macrography, structure, types of collagen, and cell viability of ACF were evaluated by immunostaining, western blotting, and cell culture assays. ACF, nanofat, and phosphate-buffered saline (9 spots/side, 0.01 mL/spot) were intradermally injected in the dorsal skin of 36 female BALB/c nude mice; the skin filling capacity and the collagen remodeling process were then investigated. Twenty-one female patients with fine rhytides in the infraorbital areas were enrolled and received clinical applications of ACF treatment. Therapeutic effects and patients' satisfaction scores were recorded. RESULTS: The mean [standard deviation] yield of ACF from 50 mL of Coleman fat was 4.91 [0.25] mL. ACF contained nonviable cells and high levels of collagen I, collagen IV, and laminin. Fibroblasts and procollagen significantly increased in ACF and ACF-treated dermis (P < 0.05). Overall, 85.7% of patients were satisfied with the therapy results, and no infections, injection site nodules, or other unwanted side effects were observed. CONCLUSIONS: ACF significantly improved dermal thickness and collagen synthesis and may serve as a potential autologous skin filler.


Assuntos
Preenchedores Dérmicos , Envelhecimento da Pele , Tecido Adiposo , Animais , Colágeno/metabolismo , Matriz Extracelular/metabolismo , Feminino , Fibroblastos/metabolismo , Humanos , Camundongos , Camundongos Nus
12.
Front Cell Dev Biol ; 9: 722427, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34631708

RESUMO

Ultraviolet A (UVA) radiation is the major contributor to skin photoaging, associated with increased collagen degradation and reactive oxygen species (ROS) expression. Adipokines have been proven as promising therapeutic agents for skin photoaging. However, adipokine therapy is generally limited by the short in vivo release duration and biological instability. Therefore, developing a treatment that provides a sustained release of adipokines and enhanced therapeutic effects is desirable. In this study, we developed a novel mechanical processing technique to extract adipose tissue-derived ECM components, named the "adipose collagen fragment" (ACF). The physical characterization, injectability, collagen components, residual DNA/RNA and adipokine release pattern of ACF were identified in vitro. L929 cells were treated with ACF or phosphate-buffered saline for 24 h after UVA irradiation in vitro. The expression of senescence-associated xß-galactosidase (SA-ß-gal), ROS and antioxidase were investigated. Then, we evaluated its therapeutic efficacy by injecting ACF and phosphate-buffered saline, as a control, into the dermis of photoaging nude mice and harvesting skin samples at weeks 1, 2, and 4 after treatment for assessment. The content of adipokines released from ACF was identified in vivo. The collagen synthesis and collagen degradation in ACF implants were evaluated by immune staining. Dermal thickness, fibroblast expression, collagen synthesis, ROS level, antioxidase expression, capillary density, and apoptotic cell number were evaluated by histological assessment, immune staining, and polymerase chain reaction in the skin samples. We demonstrated that ACF is the concentrated adipose extracellular matrix collagen fragment without viable cells and can be injected through fine needles. The lower expression of SA-ß-gal, ROS and higher expression of antioxidase were observed in the ACF-treated group. ACF undergoes collagen degradation and promotes neocollagen synthesis in ACF implants. Meanwhile, ACF serves as a sustained-release system of adipokines and exhibits a significantly higher therapeutic effect on mouse skin photoaging by enhancing angiogenesis, antioxidant abilities, antiapoptotic activities, and collagen synthesis through sustainedly releasing adipokines. To sum up, ACF is an adipokines-enriched, sustained-release extracellular matrix collagen scaffold that can prevent UVA-induced skin photoaging in mice. ACF may serve as a novel autologous skin filler for skin rejuvenation applications in the clinic.

13.
Bioresour Technol ; 328: 124827, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33609886

RESUMO

To protect microalgae that are used for photosynthetic CO2 fixation against high NO concentrations from coal-fired flue gas, 500 µM exogenous spermidine was added into Chlorella sp. solution resulting in an elevation of biomass yield by 30.5% under 327 ppm NO. Metabolomics, proteomics and enzyme activities were analyzed, revealing three effects of spermidine on Chlorella sp. resistance to NO stress. First, spermidine induced NO fixation in amino acids and their metabolites, mainly in form of 5-oxoproline (1.51-fold), which occurred through intracellular conversion reactions between citrulline and arginine. Accordingly, cellular respiration was strengthened along with a weakened NO inhibition, which enhanced active transport with ATP consumption. Second, spermidine guarded Chlorella sp. against peroxidation damage by improving activity of antioxidant enzymes. Finally, it protected the photosynthetic system of Chlorella sp. by increasing abundance of related enzymes to enhance carbon fixation. Thus exogenous spermidine improved biomass production against NO environment.


Assuntos
Chlorella , Microalgas , Biomassa , Dióxido de Carbono , Carvão Mineral , Redes e Vias Metabólicas , Óxido Nítrico , Espermidina/farmacologia
14.
ACS Appl Mater Interfaces ; 12(26): 28975-28984, 2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32501667

RESUMO

Nitric oxide (NO) gas therapy has aroused intense interest in recent years. l-Arginine (l-Arg) reacts with reactive oxygen species (ROS) in tumor cells to generate NO. This phenomenon represents an effective method for tumor therapy. However, endogenous ROS levels in most types of tumor cells cannot enable an effective reaction. ß-Lapachone is generally used to increase H2O2, which can oxidize guanidine derivatives to form nitric oxide in tumor cells. In addition, based on the ferrocene (Fc)-catalyzed Fenton reaction, ·OH is generated from H2O2, and the ONOO- could be generated from an interaction between ·O2- (generated through the Haber-Weiss reaction) and NO. Arg-rich poly(ε-caprolactone) (PCL)-b-PArg, a macromolecular NO donor, was accurately synthesized to avoid premature l-Arg leakage during in vivo transport. In this design, the self-assembled PCL-b-PArg nanoparticles were dressed with the tumor-shreddable masking (PEG-b-PDMA, a negatively charged pH-sensitive hydrophilic diblock polymer), to prepare P-lapa-Fc nanoparticles and hide penetrative capability in the circulation. The experimental results confirmed that this synergistic therapy based on ROS and NO had a significant inhibitory effect on cancer cells, thereby providing new inspiration for NO gas treatment.


Assuntos
Óxido Nítrico/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Arginina/química , Linhagem Celular Tumoral , Portadores de Fármacos/química , Humanos , Peróxido de Hidrogênio/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Polímeros/química
15.
ACS Appl Mater Interfaces ; 11(29): 25654-25663, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31246402

RESUMO

The reactive oxygen species (ROS)-responsive intelligent drug delivery system has developed rapidly in recent years. However, because of the low concentration of ROS in most types of tumor cells, it is not possible to rapidly and effectively stimulate the drug delivery system to release the active drug. Here, we introduced "sequential induced activation processes" for efficient tumor therapy by designing a new ROS-responsive drug release platform. ß-Lapachone, a positively charged nitrogen mustard (NM) prodrug, and two diblock molecules (mPEG-AcMH and PAsp-AcMH) are self-assembled to form prodrug primary micelles, which are further aggregated into nanoparticles that facilitate drug codelivery. When administered by intravenous injection, the nanoparticles reach the tumor site and enter the tumor cells by endocytosis. The ß-lapachone released in the tumor cells induces a large amount of H2O2, and the ROS-responsive NM prodrug is activated to form activated NM, quinone methide, and boric acid under the induction of H2O2. The activated NM leads to tumor cell apoptosis.


Assuntos
Portadores de Fármacos , Naftoquinonas , Neoplasias Experimentais , Animais , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Preparações de Ação Retardada/farmacologia , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Endocitose , Feminino , Células HeLa , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Naftoquinonas/química , Naftoquinonas/farmacocinética , Naftoquinonas/farmacologia , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/metabolismo , Neoplasias Experimentais/patologia , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
Mycopathologia ; 183(4): 679-689, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29572768

RESUMO

BACKGROUND: Candidemia is one of the most common nosocomial bloodstream infections. Early diagnosis and antifungal treatment improve clinical outcomes in some studies but not all, with diverse data reported from different institutions. Similarly, antifungal resistance is more common in the USA than in Europe, but there is little data regarding the microbiology and clinical course of candidemia in adult patients in Asia. AIMS: (1) To capture species distribution and drug resistance rates among Candida bloodstream isolates, (2) to describe clinical features of candidemia, and (3) to identify factors associated with all-cause mortality, with emphasis on early initiation of antifungal treatment, at a large tertiary University Hospital in China. METHODS: In this single-center retrospective study, we identified all patients with candidemia, between 2008 and 2014. Demographic and clinical characteristics, microbiological information, details of antifungal therapy and clinical outcomes were collected. RESULTS: We studied 166 patients. 71 (42.8%) had cancer. Candida albicans was the most frequent species (37.3%), followed by C. parapsilosis (24.1%), C. tropicalis (22.8%), and C. glabrata (14.5%). Antifungal resistance was more frequent in non-albicans strains and especially C. glabrata. Twenty patients received inappropriate treatment with all-cause mortality of 35%. The remaining 146 patients had significantly lower mortality (21.9%, P = 0.045). Among patients who received antifungal treatment, mortality rate increased with time to appropriate antifungal therapy (AAT): 13.7%, for < 24 h, 21.1% for 24-48 h, 23.1% for > 48 h, and 32.4% among patients who received no AT (χ2 for trend P = 0.039). Initiating AAT more than 24 h after blood culture collection was an independent risk factor for mortality, after adjustment for other confounders (OR 7.1, 95% CI 1.3-39.4, P = 0.024). CONCLUSIONS: Candida albicans was the most frequent cause of candidemia at a large tertiary hospital in China, but antifungal resistance is a growing concern among non-albicans Candida species. The mortality rate of patients treated with ineffective antifungal agents based on in vitro susceptibilities was similar to that of patients who received no treatment at all, and delayed initiation of antifungal treatment was associated with increased risk of death.


Assuntos
Antifúngicos/farmacologia , Candida/classificação , Candida/isolamento & purificação , Candidemia/microbiologia , Candidemia/mortalidade , Farmacorresistência Fúngica , Adulto , Idoso , Idoso de 80 Anos ou mais , Antifúngicos/administração & dosagem , Candida/efeitos dos fármacos , Candidemia/tratamento farmacológico , Candidemia/patologia , China/epidemiologia , Feminino , Hospitais Universitários , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Centros de Atenção Terciária , Resultado do Tratamento , Adulto Jovem
17.
Chem Commun (Camb) ; 53(91): 12302-12305, 2017 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-29094131

RESUMO

Entirely oligosaccharide-based supramolecular amphiphiles were constructed via host-guest interactions between ferrocene-terminated acetylated-maltoheptaose (Fc-AcMH) and ß-cyclodextrin-terminated four-arm star maltoheptaose (MH4-ß-CD). The amphiphiles could self-assemble to form spherical supramolecular nanoparticles to provide efficient drug delivery platforms. The combination of a pH-sensitive covalent acetal group and the oxidation-sensitive noncovalent host-guest interaction of ß-CD and ferrocene provided the obtained fully oligosaccharide-based supramolecular amphiphiles. The structures of these amphiphiles could respond to the intracellular microenvironment.


Assuntos
Sistemas de Liberação de Medicamentos , Compostos Ferrosos/química , Glucanos/química , Metalocenos/química , Oligossacarídeos/química , beta-Ciclodextrinas/química , Antibióticos Antineoplásicos/química , Antibióticos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Doxorrubicina/farmacologia , Corantes Fluorescentes/química , Corantes Fluorescentes/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Substâncias Macromoleculares/química , Micelas , Nanopartículas/química , Imagem Óptica , Tamanho da Partícula
18.
Biomed Pharmacother ; 85: 218-224, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27914827

RESUMO

BACKGROUND: In vitro culture of neural stem cell-derived neurons serves as an excellent model to study anesthetic-induced neurotoxicity. In our study, we examined the functional role of long non-coding RNA, IGF2AS, in regulating ketamine-induced neurotoxicity in murine neural stem cells. METHODS: Murine E18.5 brain-derived neural stem cells were cultured in vitro. During neural differentiation stage, ketamine-induced gene expression changes of IGF2 and IGF2AS were recorded by qRT-PCR. Neural stem cell culture was then infected by IGF2AS siRNA. The protective effect of IGF2AS inhibition on ketamine-induced apoptosis and neurite loss was assessed by TUNEL and neurite growth assays. BDNF and Akt, two candidates of downstream signaling pathways associated with IGF2AS inhibition, were further examined by western blot in neural stem cell culture. RESULTS: In neural stem cell culture, IGF2 was downregulated, but IGF2AS upregulated by in vitro treatment of ketamine in dose-dependent manner. Transfection of IGF2AS-specific siRNA effectively downregulated endogenous IGF2AS expression in neural stem cells. In addition, IGF2AS inhibition significantly alleviated ketamine-induced neuronal apoptosis and neurite loss in neural stem cell-derived neurons. Western blot study revealed that IGF2AS inhibition upregulated downstream pro-neuronal signaling pathway proteins BDNF and Akt. CONCLUSIONS: Inhibiting endogenous IGF2AS can protect anesthetic-induced neurotoxicity in neural stem cells, possibly through complimentary IGF2 upregulation and its associated downstream signaling pathways.


Assuntos
Anestésicos Dissociativos/toxicidade , Apoptose/efeitos dos fármacos , Células-Tronco Embrionárias/efeitos dos fármacos , Ketamina/toxicidade , Degeneração Neural , Células-Tronco Neurais/efeitos dos fármacos , RNA Longo não Codificante/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Relação Dose-Resposta a Droga , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/patologia , Feminino , Regulação da Expressão Gênica , Idade Gestacional , Fator de Crescimento Insulin-Like II/genética , Fator de Crescimento Insulin-Like II/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neuritos/patologia , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , Interferência de RNA , RNA Longo não Codificante/genética , Transfecção
19.
Biomed Pharmacother ; 82: 298-303, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27470366

RESUMO

BACKGROUND: Long non-coding RNA IGF2AS was initially identified as a cancer regulator in wilm's tumors. In this study, IGF2AS was investigated of its functions in inducing neural development and protecting local-anesthetic induced neurotoxicity in dorsal root ganglion (DRG) in spinal cord. METHODS: Explant of mouse spinal cord DRG was transfected with IGF2AS specific siRNA. The effect of IGF2AS inhibition on neural development was assessed by neurite growth assay, qRT-PCR and western blot assay, respectively. IGF2AS-downregulated DRG explant was then exposed to local anesthetic agent, lidocaine in vitro. The possible protective effects of IGF2AS inhibition on lidocaine-induced DRG neuron apoptosis and neurite loss were further assessed by TUNEL assay, neurite growth assay, qRT-PCR and western blot assays. RESULTS: SiRNA-mediated IGF2AS inhibition promoted neuronal growth, and induced IGF2, BDNF and NT3 upregulations at both gene and protein expressions. In lidocaine-exposed DRG neurons, endogenous IGF2AS inhibition was effective to protect local-anesthetic induced neuronal apoptosis and neurite loss. Further molecular characterization demonstrated that the neuronal protection of IGF2AS inhibition was also associated with upregulations of IGF2, BDNF and NT3 in DRG neurons. CONCLUSIONS: Inhibiting endogenous IGF2AS may promote neuronal growth and protect local-anesthetic induced neurotoxicity in DRG neurons, possibly through complimentary IGF2 upregulation and autocrine activation neurotrophin genes.


Assuntos
Anestésicos Locais/toxicidade , Gânglios Espinais/patologia , Neurônios/citologia , Neurotoxinas/toxicidade , RNA Longo não Codificante/antagonistas & inibidores , Animais , Animais Recém-Nascidos , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Lidocaína/toxicidade , Camundongos Endogâmicos C57BL , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , RNA Longo não Codificante/metabolismo
20.
Antimicrob Agents Chemother ; 60(6): 3348-54, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27001817

RESUMO

The objective of the study was to determine the effects of Candida albicans respiratory tract colonization on Acinetobacter baumannii pneumonia in a rat model. Rats were colonized with C. albicans by instillation of 3 × 10(6) CFU into their airways, while sterile saline was instilled in the control group. The colonized rats were further divided into two groups: treated with amphotericin B or not. The rats were subsequently infected with A. baumannii (10(8) CFU by tracheobronchial instillation). A. baumannii lung CFU counts, cytokine lung levels, and rates of A. baumannii pneumonia were compared between groups. In vitro expression of A. baumannii virulence genes was measured by reverse transcription (RT)-PCR after 24-hour incubation with C. albicans or with Mueller-Hinton (MH) broth alone. Rats with Candida colonization developed A. baumannii pneumonia more frequently and had higher A. baumannii CFU burdens and heavier lungs than controls. After A. baumannii infection, lung interleukin 17 (IL-17) concentrations were lower and gamma interferon (IFN-γ) concentrations were higher in Candida-colonized rats than in controls. Candida-colonized rats treated with amphotericin B had a decreased rate of A. baumannii pneumonia and lower IFN-γ levels but higher IL-17 levels than untreated rats. Expression of basC, barB, bauA, ptk, plc2, and pld2 was induced while expression of ompA and abaI was suppressed in A. baumannii cultured in the presence of C. albicans C. albicans colonization facilitated the development of A. baumannii pneumonia in a rat model. Among Candida-colonized rats, antifungal treatment lowered the incidence of A. baumannii pneumonia. These findings could be due to modification of the host immune response and/or expression of A. baumannii virulence genes by Candida spp.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/patogenicidade , Antifúngicos/uso terapêutico , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Pneumonia/tratamento farmacológico , Pneumonia/microbiologia , Acinetobacter baumannii/metabolismo , Animais , Candida albicans/metabolismo , Interleucina-10/metabolismo , Interleucina-17/metabolismo , Interleucina-2/metabolismo , Interleucina-5/metabolismo , Interleucina-6/metabolismo , Pulmão/metabolismo , Pulmão/microbiologia , Masculino , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real
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