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1.
Spectrochim Acta A Mol Biomol Spectrosc ; 253: 119602, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33667889

RESUMO

Motivated from increasing demands of non-contact optical temperature sensing, the Yb3+-Er3+ and Eu3+ doped NaY9Si6O26 (NYS) oxide phosphors were designed by high-temperature solid-state reaction method. The phase purity of the as-prepared samples was checked from XRD patterns. For the upconversion luminescence in NYS:Yb3+,Er3+, the optimal Er3+ doping content was determined to be 1 mol%, and the characteristic emission peaks of Er3+ were observed in the region of 500-700 nm. In Eu3+ activated NYS phosphors, it has been found that the emissions originating in 5D1 and 5D0 levels demonstrate different change tendencies in intensity with Eu3+ doping concentration. By studying the temperature-dependent luminescent spectra, it was indicated that the emissions intensities from different excited states of Er3+ change differently with temperature. Two kinds of fluorescence intensity ratio (FIR) strategies were used in NYS:10%Yb3+,1%Er3+, containing thermally-coupled levels and non-thermally-coupled levels. In the NYS:3%Eu3+ phosphor, it was found that the FIR for 577 and 536 nm emissions follows a linear relation with temperature. The high sensitivities in the present phosphors indicate the potential application in optical temperature sensing.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 251: 119431, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33461136

RESUMO

A series of Ca5.93-m-x-2ySrmBa(PO4)4O:xEu2+,yCe3+,yLi+ (0 ≤ m ≤ 0.5, 0 ≤ x ≤ 0.07, 0 ≤ y ≤ 0.05) phosphors were designed via solid-state reaction method, and the photoluminescence properties were studied for application in white light-emitting diodes (LEDs). When a small amount of Sr2+ was introduced into the initial Ca6Ba(PO4)4O host, the solid solution was formed, which was verified by the XRD technique. The Eu2+ in the host shows intense yellow emitting light, which can be largely enhanced by incorporating Sr2+ in the host. When the Ce3+ was doped into the host, blue emission was received under 380 nm excitation, and the optimal Ce3+ concentration is for y = 0.04. Very efficient energy transfer (ET) from Ce3+ to Eu2+ appeared in the Ce3+-Eu2+ codoped samples, and the yellow emission of Eu2+ can be further enhanced by this ET. The thermal-quenching luminescence of the as-prepared samples was evaluated by the temperature-dependent emission spectra, which indicated that the introduction of Sr2+ can improve the thermally luminescence stability of Eu2+. The fabrication of the LEDs device revealed that the Ce3+-Eu2+ activated samples in this work could show potential applications in white LEDs.

3.
Artif Intell Med ; 111: 102004, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33461688

RESUMO

Functional connectivity networks (FCNs) provide a potential way for understanding the brain organizational patterns and diagnosing neurological diseases. Currently, researchers have proposed many methods for FCN construction, among which the most classic example is Pearson's correlation (PC). Despite its simplicity and popularity, PC always results in dense FCNs, and thus a thresholding strategy is usually needed in practice to sparsify the estimated FCNs prior to the network analysis, which undoubtedly causes the problem of threshold parameter selection. As an alternative to PC, sparse representation (SR) can directly generate sparse FCNs due to the l1 regularizer in the estimation model. However, similar to the thresholding scheme used in PC, it is also challenging to determine suitable values for the regularization parameter in SR. To circumvent the difficulty of parameter selection involved in these traditional methods, we propose a hyperparameter-free method for FCN construction based on the global representation among fMRI time courses. Interestingly, the proposed method can automatically generate sparse FCNs, without any thresholding or regularization parameters. To verify the effectiveness of the proposed method, we conduct experiments to identify subjects with mild cognitive impairment (MCI) and Autism spectrum disorder (ASD) from normal controls (NCs) based on the estimated FCNs. Experimental results on two benchmark databases demonstrate that the achieved classification performance of our proposed scheme is comparable to four conventional methods.

4.
Biomaterials ; 269: 120666, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33461057

RESUMO

The presence of immunosuppressive innate immune cells such as myeloid derived suppressor cells (MDSCs), Ly6C-high monocytes, and tumor-associated macrophages (TAMs) at a tumor can inhibit effector T cell and NK cell function. Immune checkpoint blockade using anti-PD-1 antibody aims to overcome the immune suppressive environment, yet only a fraction of patients responds. Herein, we test the hypothesis that cargo-free PLG nanoparticles administered intravenously can divert circulating immune cells from the tumor microenvironment to enhance the efficacy of anti-PD-1 immunotherapy in the 4T1 mouse model of metastatic triple-negative breast cancer. In vitro studies demonstrate that these nanoparticles decrease the expression of MCP-1 by 5-fold and increase the expression of TNF-α by more than 2-fold upon uptake by innate immune cells. Intravenous administration of particles results in internalization by MDSCs and monocytes, with particles detected in the liver, lung, spleen, and primary tumor. Nanoparticle delivery decreased the abundance of MDSCs in circulation and in the lung, the latter being the primary metastatic site. Combined with anti-PD-1 antibody, nanoparticles significantly slowed tumor growth and resulted in a survival benefit. Gene expression analysis by GSEA indicated inflammatory myeloid cell pathways were downregulated in the lung and upregulated in the spleen and tumor. Upregulation of extrinsic apoptotic pathways was also observed in the primary tumor. Collectively, these results demonstrate that cargo-free PLG nanoparticles can reprogram immune cell responses and alter the tumor microenvironment in vivo to overcome the local immune suppression attributed to myeloid cells and enhance the efficacy of anti-PD-1 therapy.

5.
Meat Sci ; 172: 108347, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33091723

RESUMO

This study defined the pH threshold for dark cutting beef of Asian consumers using a web-based survey and examined their preferences for beef appearance. Ninety individual images of beef steaks with different pH values were randomly selected to be scored by 4322 respondents. Gender, age and beef eating habits of respondents were found to impact on color preferences. With respondent's visual score of 4 set as the acceptance threshold, linear regression analysis between visual scores and beef instrumental colorimetrics, showed that the acceptance thresholds of instrumental color values were L* ≥ 31.4, a* ≥ 16.4, b* ≥ 6.5, chroma ≥17.4 and hue ≥22.5. These corresponded to pH threshold values of 6.11, 6.20, 6.28, 6.25 and 6.29, respectively. This pH benchmark (6.11 to 6.29) for dark cutters is higher than pH thresholds applied in most countries, indicating that Asian consumers prefer darker meat than expected, however, the likely tenderness of beef with pH's at this level merits consideration.

6.
Transpl Infect Dis ; : e13544, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33326670

RESUMO

BACKGROUND: Human herpesvirus 6 (HHV-6) reactivation is relatively common after allogeneic hematopoietic stem cell transplantation (allo-HSCT). However, the incidence of HHV-6 reactivation and the clinical outcomes following unmanipulated haploidentical HSCT (haplo-HSCT) remain unknown. METHOD: We prospectively monitored blood HHV-6 DNA using real-time quantitative polymerase chain reaction weekly until day 100 post unmanipulated haplo-HSCT in patients with hematological malignancies. RESULTS: From November 2016 to March 2017, 102 patients (58 male and 44 female, median age 25(2-58) years old) were enrolled. Within 100 days post-transplantation, 27 patients (27/136, 19.9%) developed HHV-6 viremia with a median onset time of 14 (7-98) days. The cumulative incidence of HHV-6 reactivation on day 100 post-HSCT was 25.5 ± 4.3% in haplo-HSCT. The median HHV-6 copy number was 1.45 × 103 (5.48 × 102 -2.00 × 104 ) copies/ml. The HHV-6 viremia duration time was 7 days in 23 patients, 14 days in one patient and 21 days in one patient. In multivariate analysis, prior HHV-6 reactivation was an independent risk factor for grade 2-4 graft-versus-host disease (GVHD). But it did not influence the overall survival (OS)(HR 1.624, 95%CI 0.768-3.432, P = .204), disease-free survival (DFS) (HR 1.640, 95%CI 0.799-3.367, P = .177) and non-relapse mortality (NRM) (HR 1.644, 95%CI 0.670-4.038, P = .278). CONCLUSION: The reactivation of HHV-6 after unmanipulated haploidentical transplantation predicts the occurrence of grade 2-4 a-GVHD, but it may not influence the overall survival (OS), disease-free survival (DFS) and non-relapse mortality (NRM).

7.
Int J Biol Sci ; 16(14): 2527-2541, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32792855

RESUMO

Excess glucocorticoid (GC) production is known to induce obesity and insulin resistance through increased activation of the glucocorticoid receptor (GR). The molecular mechanism for the non-genomic effects of excessive circulating GC on the insulin-signalling pathway in skeletal muscle is unknown. The plant alkaloid berberine has been shown to attenuate insulin resistance and inhibit gluconeogenesis in type 2 diabetic animals. A highly bioavailable berberine formulation termed Huang-Gui solid dispersion (HGSD), is a preparation of berberine coupled to sodium caprate and this markedly improving berberines bioavailability. Here we examined how HGSD treatment attenuated GR-mediated alteration in PI3K signalling and insulin resistance in diabetic rats, dexamethasone-treated mice and in insulin resistant C2C12 skeletal muscle cells. Blood glucose and skeletal muscle GC levels were increased and insulin signalling impaired in skeletal muscle of type 2 diabetic rats compared to controls. Treatment of these animals with HGSD restored blood glucose and skeletal muscle GC levels to that of controls. Insulin resistant C2C12 skeletal muscle cells exhibited impaired insulin signalling compared to controls and treatment of HGSD and RU486, an antagonist of GR, restored insulin signalling to that of control cells. Administration of dexamethasone to mice increased GR/GRα-associated PI3K and reduced IRS1-associated PI3K, phosphorylated-AKT, and membrane GLUT4 translocation resulting in a higher blood glucose concentration compared to controls. HGSD treatment of these mice improved insulin resistance by reducing the association of GR/GRα with PI3K. Excess GC-induced insulin resistance is mediated by increased association of GR with PI3K and treatment with HGSD attenuates these effects. We hypothesize that HGSD may be a promising candidate drug for the treatment of type 2 diabetes by reducing the association of GR with PI3K in skeletal muscle.

8.
BMC Med Educ ; 20(1): 100, 2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32234040

RESUMO

BACKGROUND: The flipped-classroom model is increasingly being adopted in competency-based medical education. However, it poses a major challenge to students who have not mastered self-regulated learning strategies. This study explores which self-regulated learning skills affect student learning performance in the first 2 years of medical school at a university in the midwestern United States. METHODS: Survey data were used to assess how 146 first- and second-year medical students' use of self-regulated learning strategies affected their performance on standardized tests. RESULTS: Based on the results of regression analysis and content analysis, it was found that the use of peer learning and help-seeking positively affected the performance of first- and second-year students, respectively; whereas the use of rehearsal had a negative effect on student learning outcomes. CONCLUSIONS: The study findings imply that during the transition period from traditional lecture-intensive learning to flipped-classroom learning, promoting peer learning and help-seeking could significantly improve students' academic achievement.

10.
Eur J Pharmacol ; 873: 172955, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32001218

RESUMO

Glomerular mesangial matrix expansion and cell autophagy are the most important factors in the development of kidney damage under diabetic conditions. The activation of AMPK might be an important treatment target for diabetic nephropathy. Berberine has multiple effects on all types of diabetic complications as an activator of AMPK. However, the poor bioavailability of berberine limits its clinical applications. Huang-Gui Solid Dispersion (HGSD), a new formulation of berberine developed in our lab, has 4-fold greater bioavailability than berberine. However, its therapeutic application and mechanism still need to be explored. In the present study, the effect of HGSD on kidney function in type 2 diabetic rats and db/db mice was investigated. The results demonstrated that HGSD improved kidney function in these two animal models, decreased the glomerular volume and increased autophagy. Meanwhile, AMPK phosphorylation levels and autophagy-related protein expression were significantly increased, and extracellular matrix protein deposition-related protein expression was decreased after treatment. The present study indicated that HGSD protected against diabetic kidney dysfunction by inhibiting glomerular mesangial matrix expansion and activating autophagy. The mechanism of HGSD in the treatment of diabetic nephropathy might be connected to the activation of AMPK phosphorylation.


Assuntos
Autofagia/efeitos dos fármacos , Berberina/farmacologia , Nefropatias Diabéticas/tratamento farmacológico , Células Mesangiais/efeitos dos fármacos , Proteínas Quinases Ativadas por AMP/efeitos dos fármacos , Animais , Berberina/farmacocinética , Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/complicações , Nefropatias Diabéticas/patologia , Composição de Medicamentos , Ativação Enzimática/efeitos dos fármacos , Proteínas da Matriz Extracelular/metabolismo , Teste de Tolerância a Glucose , Testes de Função Renal , Masculino , Fosforilação , Ratos , Ratos Wistar
11.
Reprod Domest Anim ; 55(3): 384-392, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31945221

RESUMO

Hypothalamic gonadotropin-releasing hormone (GnRH) controls the activity of hypothalamic-pituitary-gonadal axis and plays a key role in the reproductive performance of animals. In this study, five single nucleotide polymorphisms (SNPs), namely g.991T > C, g.1041T > C g.3424T > C, g.3462C > A and g.3463Inde A, were detected in the GnRH gene of 162 water buffaloes by Sanger sequencing. Each SNP was associated with more than two sperm quality traits of ejaculate volume, sperm concentration, post-thaw sperm motility and sperm abnormality. g.3424T > C and g.3462C > A were related to these four traits and had a remarkable effect on ejaculate volume. The three other SNPs were related to sperm concentration, post-thaw sperm motility and sperm abnormality. Moreover, six haplotypes (H1: TCCAI, H2: CTTC-, H3: TCCCI, H4: CTTA-, H5: CCTA- and H6: CTCC-) composed of five SNPs comprising seven different combined genotypes were generated by linkage disequilibrium analysis. Statistics followed by one-way ANOVA indicated that water buffaloes with the haplotype combination H1H1 had the highest genotypic frequency, and those with the H4H4 haplotype combination had the highest ejaculate volume. The sperm concentration of those with haplotype combination H1H5 was higher than that of the other genotypes. In summary, our study showed a remarkable association between the SNPs of GnRH and sperm quality traits of Chinese water buffalo.


Assuntos
Búfalos/genética , Hormônio Liberador de Gonadotropina/genética , Polimorfismo de Nucleotídeo Único , Análise do Sêmen , Animais , Búfalos/fisiologia , Ejaculação , Congelamento , Desequilíbrio de Ligação , Masculino , Preservação do Sêmen/veterinária , Contagem de Espermatozoides , Motilidade Espermática/genética , Espermatozoides/anormalidades , Espermatozoides/fisiologia
12.
Int J Biol Macromol ; 147: 233-240, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31923517

RESUMO

The polysaccharide (OJP1), extracted from the root of Ophiopogon japonicus, is a well-known traditional Chinese medicine used to treat cardiovascular diseases. The present study was set up to investigate the cardioprotective effect of OJP1 on isoproterenol (ISO)-induced myocardial ischemia injury in rats. Results showed that pretreatment with OJP1 (100, 200 and 300 mg/kg) significantly reduced ISO-induced ST-segment elevation and the heart index, attenuated the levels of marker enzymes (AST, LDH, CK and CK-MB), along with a significantly enhanced the activities of ATPases. Moreover, pretreatment with OJP1 not only enhanced the activities of SOD, GPx and CAT in serum and myocardium, but also decreased the level of MDA. The biochemical and histopathological analysis also showed that OJP1 can alleviate the myocardial injury induced by ISO. Taken together, our results indicated that oral administration of OJP1 offered significant cardioprotective effect against the damage induced by ISO through enhancement of endogenous antioxidants.


Assuntos
Cardiotônicos/uso terapêutico , Isquemia Miocárdica/tratamento farmacológico , Ophiopogon/química , Polissacarídeos/uso terapêutico , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , ATPase de Ca(2+) e Mg(2+) , Cardiotônicos/farmacologia , Catalase/metabolismo , Eletrocardiografia , Endotelina-1/metabolismo , Glutationa Peroxidase/metabolismo , Isoproterenol , Malondialdeído/metabolismo , Isquemia Miocárdica/sangue , Isquemia Miocárdica/induzido quimicamente , Isquemia Miocárdica/diagnóstico por imagem , Miocárdio/enzimologia , Miocárdio/patologia , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase/metabolismo , Especificidade de Órgãos/efeitos dos fármacos , Polissacarídeos/farmacologia , Ratos Sprague-Dawley , Albumina Sérica Humana/metabolismo , ATPase Trocadora de Sódio-Potássio/metabolismo , Superóxido Dismutase/metabolismo
13.
Biotechnol Bioeng ; 117(1): 210-222, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31544959

RESUMO

Metastases are preceded by stochastic formation of a hospitable microenvironment known as the premetastatic niche, which has been difficult to study. Herein, we employ implantable polycaprolactone scaffolds as an engineered premetastatic niche to independently investigate the role of interleukin-10 (IL10), CXCL12, and CCL2 in recruiting immune and tumor cells and impacting breast cancer cell phenotype via lentiviral overexpression. Lentivirus delivered from scaffolds in vivo achieved sustained transgene expression for 56 days. IL10 lentiviral expression, but not CXCL12 or CCL2, significantly decreased tumor cell recruitment to scaffolds in vivo. Delivery of CXCL12 enhanced CD45+ immune cell recruitment to scaffolds while delivery of IL10 reduced immune cell recruitment. CCL2 did not alter immune cell recruitment. Tumor cell phenotype was investigated using conditioned media from immunomodulated scaffolds, with CXCL12 microenvironments reducing proliferation, and IL10 microenvironments enhancing proliferation. Migration was enhanced with CCL2 and reduced with IL10-driven microenvironments. Multiple linear regression identified populations of immune cells associated with tumor cell abundance. CD45+ immune and CD8+ T cells were associated with reduced tumor cell abundance, while CD11b+Gr1+ neutrophils and CD4+ T cells were associated with enhanced tumor cell abundance. Collectively, biomaterial scaffolds provide a tool to probe the formation and function of the premetastatic niche.

14.
Ann Biomed Eng ; 48(1): 477-489, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31549327

RESUMO

For most cancers, metastasis is the point at which disease is no longer curable. Earlier detection of metastasis, when it is undetectable by current clinical methods, may enable better outcomes. We have developed a biomaterial implant that recruits metastatic cancer cells in mouse models of breast cancer. Here, we investigate spectral ultrasound imaging (SUSI) as a non-invasive strategy for detecting metastasis to the implanted biomaterial scaffolds. Our results show that SUSI, which detects parameters related to tissue composition and structure, identified changes at an early time point when tumor cells were recruited to scaffolds in orthotopic breast cancer mouse models. These changes were not associated with acellular components in the scaffolds but were reflected in the cellular composition in the scaffold microenvironment, including an increase in CD31 + CD45-endothelial cell number in tumor bearing mice. In addition, we built a classification model based on changes in SUSI parameters from scaffold measurements to stratify tumor free and tumor bearing status. Combination of a linear discriminant analysis and bagged decision trees model resulted in an area under the curve of 0.92 for receiver operating characteristics analysis. With the potential for early non-invasive detection, SUSI could facilitate clinical translation of the scaffolds for monitoring metastatic disease.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Tecidos Suporte , Ultrassonografia/métodos , Animais , Materiais Biocompatíveis , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos
15.
Cancer Res ; 80(3): 602-612, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31662327

RESUMO

Monitoring metastatic events in distal tissues is challenged by their sporadic occurrence in obscure and inaccessible locations within these vital organs. A synthetic biomaterial scaffold can function as a synthetic metastatic niche to reveal the nature of these distal sites. These implanted scaffolds promote tissue ingrowth, which upon cancer initiation is transformed into a metastatic niche that captures aggressive circulating tumor cells. We hypothesized that immune cell phenotypes at synthetic niches reflect the immunosuppressive conditioning within a host that contributes to metastatic cell recruitment and can identify disease progression and response to therapy. We analyzed the expression of 632 immune-centric genes in tissue biopsied from implants at weekly intervals following inoculation. Specific immune populations within implants were then analyzed by single-cell RNA-seq. Dynamic gene expression profiles in innate cells, such as myeloid-derived suppressor cells, macrophages, and dendritic cells, suggest the development of an immunosuppressive microenvironment. These dynamics in immune phenotypes at implants was analogous to that in the diseased lung and had distinct dynamics compared with blood leukocytes. Following a therapeutic excision of the primary tumor, longitudinal tracking of immune phenotypes at the implant in individual mice showed an initial response to therapy, which over time differentiated recurrence versus survival. Collectively, the microenvironment at the synthetic niche acts as a sentinel by reflecting both progression and regression of disease. SIGNIFICANCE: Immune dynamics at biomaterial implants, functioning as a synthetic metastatic niche, provides unique information that correlates with disease progression. GRAPHICAL ABSTRACT: http://cancerres.aacrjournals.org/content/canres/80/3/602/F1.large.jpg.See related commentary by Wolf and Elisseeff, p. 377.


Assuntos
Materiais Biocompatíveis , Recidiva Local de Neoplasia , Animais , Carvão Mineral , Progressão da Doença , Camundongos , Resultado do Tratamento , Microambiente Tumoral
16.
ACS Appl Mater Interfaces ; 11(51): 48162-48171, 2019 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-31777247

RESUMO

Laser reduction of graphene oxide (GO) produces graphene effectively. As a low-power laser source, commercial digital video disc (DVD) drives provide a versatile platform to produce reduced graphene films in designed 2D patterns. However, research on how GO characteristics affect its laser reduction efficiency in DVD drives is rarely conducted. Here, we investigate how heating the GO dispersion affects the photoreduction process of GO films in a LightScribe DVD drive. Without noticeably changing the oxygen content, such mild heat treatment significantly improves GO's absorption in the visible region, resulting in significant enhancement on GO's laser reduction efficiency. We demonstrate that the laser reduction efficiency increases with the increasing treatment time. The enhanced reduction level greatly improves the performance of laser-scribed graphene electrodes in applications such as glucose sensors (with an optimal linear response range up to 2550 µM) and supercapacitors (with an optimal areal capacity of 1.37 mF cm-2 at the scan rate of 50 mV s-1). This proposed approach provides general insights into the production of laser-reduced graphene with low-power laser sources, for advanced device applications such as wearable electronics and flexible microelectronics.

18.
Proc Natl Acad Sci U S A ; 116(30): 14947-14954, 2019 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-31285339

RESUMO

Traumatic primary spinal cord injury (SCI) results in paralysis below the level of injury and is associated with infiltration of hematogenous innate immune cells into the injured cord. Methylprednisolone has been applied to reduce inflammation following SCI, yet was discontinued due to an unfavorable risk-benefit ratio associated with off-target effects. In this study, i.v. administered poly(lactide-coglycolide) nanoparticles were internalized by circulating monocytes and neutrophils, reprogramming these cells based on their physicochemical properties and not by an active pharmaceutical ingredient, to exhibit altered biodistribution, gene expression, and function. Approximately 80% of nanoparticle-positive immune cells were observed within the injury, and, additionally, the overall accumulation of innate immune cells at the injury was reduced 4-fold, coinciding with down-regulated expression of proinflammatory factors and increased expression of antiinflammatory and proregenerative genes. Furthermore, nanoparticle administration induced macrophage polarization toward proregenerative phenotypes at the injury and markedly reduced both fibrotic and gliotic scarring 3-fold. Moreover, nanoparticle administration with the implanted multichannel bridge led to increased numbers of regenerating axons, increased myelination with about 40% of axons myelinated, and an enhanced locomotor function (score of 6 versus 3 for control group). These data demonstrate that nanoparticles provide a platform that limits acute inflammation and tissue destruction, at a favorable risk-benefit ratio, leading to a proregenerative microenvironment that supports regeneration and functional recovery. These particles may have applications to trauma and potentially other inflammatory diseases.


Assuntos
Imunomodulação , Metilprednisolona/administração & dosagem , Monócitos/imunologia , Nanopartículas/metabolismo , Neutrófilos/imunologia , Traumatismos da Medula Espinal/terapia , Animais , Feminino , Imunidade Inata , Injeções Intravenosas , Metilprednisolona/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Nanopartículas/administração & dosagem , Nanopartículas/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Traumatismos da Medula Espinal/imunologia
19.
Epigenomics ; 11(11): 1283-1305, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31355678

RESUMO

Aim: To investigate the effect of UBE2T gene on radiotherapy for osteosarcoma. Materials & methods: Gene Expression Omnibus database, RT-qPCR and immunohistochemical analysis were performed. Cell proliferation and cell cycle experiments were conducted after knockdown of UBE2T. Cell scratch, reactive oxygen species production and apoptosis experiments were conducted after the combination of radiotherapy and UBE2T silencing. Then the xenograft mode was further conducted. Results: UBE2T was highly expressed in human osteosarcoma. Suppression of UBE2T inhibited osteosarcoma cell proliferation and induced cell cycle arrest at the G2/M phase. Downregulation of UBE2T combined with radiation can substantially inhibit clonal formation and migration, and promote apoptosis of osteosarcoma cells in vitro and in vivo. Conclusion: UBE2T downregulation can enhance the radiosensitivity of osteosarcoma in vitro and in vivo.


Assuntos
Apoptose , Neoplasias Ósseas/radioterapia , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Osteossarcoma/radioterapia , Tolerância a Radiação/genética , Enzimas de Conjugação de Ubiquitina/metabolismo , Animais , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Ciclo Celular , Feminino , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Osteossarcoma/metabolismo , Osteossarcoma/patologia , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas , Enzimas de Conjugação de Ubiquitina/genética , Raios X , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Int J Biol Macromol ; 139: 30-39, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31306703

RESUMO

The purpose of this work is to stabilize zein nanoparticles with anionic polysaccharides-chondroitin sulfate (CS) to overcome the poor colloidal stability of zein nanoparticles. The average molecular weight of CS was 20.51 kDa and the disaccharide composition of CS was 70.71% monosulfated disaccharide Di2S and 29.29% disulfated disaccharide Di2,6 diS. Zein/CS composite nanoparticles were fabricated by antisolvent precipitation method at pH 4.0. The optimal mass ratio of zein to CS was 1:1 (w/w). Zein/CS composite nanoparticles showed mean size of 148 nm and PDI < 0.2, maintaining great stability at pH 3.0 to 8.0. Meanwhile, these prepared nanoparticles were also stable to heat treatment and was stable to a range of ionic strength of 0-15 mM at pH 4.0 and 0-10 mM at pH 7.0. The composite nanoparticles exhibited regular spherical structures, and CS was deposited on the surface of zein mainly by electrostatic interactions. In the process, the addition of urea and sodium dodecyl sulfate indicated that it also involved both hydrogen bonding and hydrophobic interactions. In addition, cytotoxicity assay on human renal epithelial cells-293 cells indicated that zein/CS composite nanoparticles were essentially nontoxic.


Assuntos
Precipitação Química , Sulfatos de Condroitina/química , Sulfatos de Condroitina/isolamento & purificação , Nanopartículas/química , Nanotecnologia/métodos , Solventes/química , Zeína/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Concentração Osmolar , Propriedades de Superfície
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