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2.
Nat Med ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31700183

RESUMO

Type 2 diabetes is characterized by insulin resistance and a gradual loss of pancreatic beta cell mass and function1,2. Currently, there are no therapies proven to prevent beta cell loss and some, namely insulin secretagogues, have been linked to accelerated beta cell failure, thereby limiting their use in type 2 diabetes3,4. The adipokine adipsin/complement factor D controls the alternative complement pathway and generation of complement component C3a, which acts to augment beta cell insulin secretion5. In contrast to other insulin secretagogues, we show that chronic replenishment of adipsin in diabetic db/db mice ameliorates hyperglycemia and increases insulin levels while preserving beta cells by blocking dedifferentiation and death. Mechanistically, we find that adipsin/C3a decreases the phosphatase Dusp26; forced expression of Dusp26 in beta cells decreases expression of core beta cell identity genes and sensitizes to cell death. In contrast, pharmacological inhibition of DUSP26 improves hyperglycemia in diabetic mice and protects human islet cells from cell death. Pertaining to human health, we show that higher concentrations of circulating adipsin are associated with a significantly lower risk of developing future diabetes among middle-aged adults after adjusting for body mass index (BMI). Collectively, these data suggest that adipsin/C3a and DUSP26-directed therapies may represent a novel approach to achieve beta cell health to treat and prevent type 2 diabetes.

3.
Nanomedicine (Lond) ; 2019 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-31696756

RESUMO

Aim: A redox-triggered camptothecin (CPT) liposomal system was developed for an improved clinical potential in tumor therapy. Materials & methods: CPT-phosphorylcholine conjugates (CPT-SS-GPCs: CPT-SS-3-GPC and CPT-SS-11-GPC) were synthesized by conjugating CPT to glycerylphosphorylcholine via disulfide bond linker. CPT-SS-GPCs could be assembled into liposomes. Different in vitro and in vivo analyses were used to evaluate the anticancer activities of CPT-SS-GPCs. Results: CPT-SS-GPCs liposomes exhibited extremely high drug loading and uniform size of 150-200 nm. Moreover, the rapid release of parent CPT in reductive condition and high cellular uptake of CPT-SS-GPCs liposomes were observed. At last, in vitro and in vivo anticancer assay showed the enhanced efficacy of CPT-SS-GPCs liposomes. Conclusion: Redox-triggered CPT-SS-GPC liposomes have great potential in tumor therapy.

4.
J Environ Manage ; 252: 109642, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31586745

RESUMO

Hexametaphosphate intercalated green rust (hexa-P GR) was fabricated by a coprecipitation process in an anaerobic environment to improve the adsorption of hexa-P GR for Cr(VI) and the total Cr under various aqueous conditions. Three kinetic models including the pseudo-first-order, intraparticle, and Elovich were appropriate in describing the adsorption of hexa-P GR towards Cr(VI) and the total Cr. The maximum mono-layer adsorption capacities (mg/g) of hexa-P GR for Cr(VI) at pH of 2 and 7 were 87.64 and 92.25, respectively, with the theoretical maximum capacity (mg/g) of 52.73 being obtained at pH of 7. Some competing cations existing in solutions such as Al3+, Ca2+, and Mg2+ would consume more hexa-P GR to remove Cr species. The neutral and weak alkaline environment was conducive to the hexa-P GR reuse, while the strong alkaline environment was beneficial to the removal of the total Cr. The orthogonal variables including the initial pH, the flow rate, and the Cr(VI) concentration all significantly influenced Cr removal. The sequences of reaction pathways referring to the adsorption of hexa-P GR differently occurred in various pH conditions.


Assuntos
Cromo , Poluentes Químicos da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Fosfatos
5.
J Asthma ; : 1-8, 2019 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-31514546

RESUMO

Purpose: The aim of this study was to investigate the efficacy and safety of tratinterol hydrochloride in bronchial asthma (BA) treatment. Methods: Patients enrolled in this study were distributed randomly into a treatment group (tratinterol hydrochloride) and an active control group (procaterol hydrochloride) and were treated for 2 weeks after running-in. The end points were changes in pulmonary function and clinical symptoms after administration. Safety indices were physical examinations, laboratory testing and spontaneous reporting. Findings: We enrolled 732 subjects, -365 in the treatment group and 367 in the active control group. Forced expiratory volume (FEV1), significantly increased in both group after treatment (P < 0.05). Least-squares (LS) means were -0.03/in the full-analysis set (FAS) and -0.02 in the per-protocol set (PPS) set, and 95% confidence intervals (CIs) for these sets were -0.09 to 0.03 and -0.08 to 0.04, respectively. Forced expiratory volume (FVC), morning peak expiratory flow (PEF) and asthma scores were significantly different with pretreatment (P < 0.05). There was no difference in asymptomatic days or frequency of relief medicine use (P > 0.05). No serious adverse events occurred. Implications: Tratinterol hydrochloride was effective, safe and not inferior to procaterol hydrochloride in treating BA.

6.
Ann Vasc Surg ; 2019 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-31536795

RESUMO

BACKGROUND: This study aims to present the performance data on stent-graft and multilayer bare stents (MBS) joint technique in the treatment of high-risk thoracoabdominal aortic aneurysm (TAAA). METHODS: From May 2012 to December 2015, 8 selective TAAA cases (ages 46-75 years) ineligible for surgical repair underwent the stent-graft and MBS joint procedure, and were closely followed up for a median of 32 months (range 14-58). Using computed tomography images, the aneurysm size, luminal blood flow diameter, and the covered visceral branches were analyzed. RESULTS: Technical success was achieved in all patients (100%, 8/8). Twenty-four visceral branches were covered by MBS in total. There was no complication or death during hospital stay. During follow-up period, no death or complication occurred. Aneurysm shrinkage (maximum diameter decrease ≥5 mm) was observed in 7 patients. No aneurysm expansion was observed. Total aneurysm sac thrombosis was observed in all patients. The majority of covered side branches (23/24) were successfully preserved. No visceral ischemia or bleeding complications was observed during follow-up. CONCLUSIONS: Total endovascular repair of TAAA using stent-graft and MBS joint technique may be a safe and effective alternative in high surgical risk patients. More approving clinical evidences about the safety and efficacy of this procedure are anticipated.

7.
Biomed Environ Sci ; 32(8): 614-623, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488237

RESUMO

OBJECTIVE: To develop methods for determining a suitable sample size for bioequivalence assessment of generic topical ophthalmic drugs using crossover design with serial sampling schemes. METHODS: The power functions of the Fieller-type confidence interval and the asymptotic confidence interval in crossover designs with serial-sampling data are here derived. Simulation studies were conducted to evaluate the derived power functions. RESULTS: Simulation studies show that two power functions can provide precise power estimates when normality assumptions are satisfied and yield conservative estimates of power in cases when data are log-normally distributed. The intra-correlation showed a positive correlation with the power of the bioequivalence test. When the expected ratio of the AUCs was less than or equal to 1, the power of the Fieller-type confidence interval was larger than the asymptotic confidence interval. If the expected ratio of the AUCs was larger than 1, the asymptotic confidence interval had greater power. Sample size can be calculated through numerical iteration with the derived power functions. CONCLUSION: The Fieller-type power function and the asymptotic power function can be used to determine sample sizes of crossover trials for bioequivalence assessment of topical ophthalmic drugs.

8.
Biomater Sci ; 7(11): 4720-4729, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31495835

RESUMO

Herein, we report a new type of biodegradable, high surface-area gold nanodandelions (GNDs). This report possesses important features and some are the first of its kind: (1) the large scale green synthesis of GNDs with high monodispersity and a circa 100% yield with consistent chemistry, manufacturing and controls (CMC); (2) cellular/physiological degradability of GNDs leading to its disassembly into debris, which is indicative of the potential for possible body clearance; (3) precision control of the chemicophysical properties of the GNDs including shape, petal number and size, all can be judiciously fine-tuned by the synthetic parameters; (4) highly efficient radiotheranostics of GNDs encompassing better enhanced computed tomography (CT) contrast and pronounced X-ray induced reactive oxygen species (ROS) generation than conventional spherical gold nanoparticles (AuNP). It is noteworthy that the GNDs demonstrate a unique combinational effect of radiosensitization (production of superoxide anions and hydroxyl radicals) and type II photodynamic interaction (generation of singlet oxygen). Given the above, our reported GNDs are promising in clinical translation as radiotheranostics.

9.
ACS Appl Mater Interfaces ; 11(41): 37411-37420, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31556583

RESUMO

Liposomes are the most valuable nanocarriers in clinical use because of their biocompatibility, biodegradation, and effective encapsulation of hydrophilic or hydrophobic drugs. However, their applications are limited by the structure and functions of the most common phospholipids used as the main component of the liposomes. In this work, novel series of thioether phosphatidylcholines (S-PCs) and S-PC-based liposomes (S-LPs) were developed for reactive oxygen species (ROS)-responsive drug release. First of all, S-PCs with different chain lengths were synthesized by a combination of click reaction and heterogeneous esterification. Differential scanning calorimetry studies indicated that S-PCs had different phase transition temperatures depending on their chain lengths. Their critical aggregation concentrations were measured by the fluorescence probe technique indicating the self-assembly ability. After that, S-PC-based stealth liposomes (S-LPs) containing DSPE-PEG2000 and cholesterol were prepared via a classic thin-film method. Doxorubicin (DOX) as a model drug was loaded in the stealth liposomes (DOX/S-LPs) by using the ammonium sulfate gradient method with high encapsulation efficiency. DOX/S-LPs were characterized by dynamic light scattering (DLS), transmission electron microscope (TEM), and cryogenic TEM, confirming their spherical structure with the bilayer thickness of about 4 nm. The ROS sensitivity of S-PCs and S-LPs was carefully evaluated in the presence of H2O2 by means of mass spectrometry, DLS, TEM, and ultraviolet spectroscopy and release study. The results indicated the significant structural change of S-LPs after H2O2 treatment, which demonstrated that S-LPs possessed an efficient ROS-triggered disintegration because of thioether oxidation of S-PCs. Finally, in vitro and in vivo anticancer efficiency assays revealed the improved drug potency of DOX/S-LPs, which can be attributed to ROS-triggered destruction of S-LPs after the uptake by tumor cells followed by rapid release of DOX. All together, as alternatives of traditional phosphatidylcholines, S-PC-based stealth liposomes are promising ROS-responsive carriers for the controlled delivery of drugs.

10.
Langmuir ; 35(40): 13031-13039, 2019 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-31537058

RESUMO

The increasing application of gold nanoparticles (AuNPs) in biomedicine requires extensive investigation of surface modification and stabilization to maximize their advantages for the diversity of more challenging biological utilization. Herein, a thiol-mediated multifunctional phospholipid ligand was designed while disclosing a zwitterionic nature to AuNPs. The ligand was synthesized by attachment to two bidentate lipoic acid (LA) anchor groups and incorporation of a zwitterionic phosphatidylcholine (PC) group, allowing for excellent hydrophilicity. As demonstrated through ultraviolet-visible spectroscopy, appropriate 7 nm diameter AuNPs modified with a 1,2-dilipoyl-sn-glycero-3-phosphorylcholine (di-LA-PC) compact ligand exhibited the best colloidal stability in a high NaCl concentration of up to 217 mM, different temperatures, and a wide range of pH values from 3 to 11 when compared to the traditional surfactants or thiol-contained amino acid surface modification cases. These AuNPs are also stable without specific interaction to positively/negatively charged proteins, possibly leading to prolonged blood circulation after in vivo administration. Moreover, much more resistance to ligand competition of dithiothreitol was found than other thiol-coated AuNPs, which further highlighted their affinity in an aqueous system. Biocompatibility of the zwitterionic ligand di-LA-PC-modified AuNPs was finally evaluated by hemolysis and cytotoxicity tests. Cumulatively, the remarkable stability and biocompatibility of AuNPs, multicoordinated with a di-LA-PC ligand, potentially motivated them as a practical alternative for surface tailoring in biotechnology.

11.
Nat Commun ; 10(1): 4267, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31537805

RESUMO

Identifying methylation quantitative trait loci (meQTLs) and integrating them with disease-associated variants from genome-wide association studies (GWAS) may illuminate functional mechanisms underlying genetic variant-disease associations. Here, we perform GWAS of >415 thousand CpG methylation sites in whole blood from 4170 individuals and map 4.7 million cis- and 630 thousand trans-meQTL variants targeting >120 thousand CpGs. Independent replication is performed in 1347 participants from two studies. By linking cis-meQTL variants with GWAS results for cardiovascular disease (CVD) traits, we identify 92 putatively causal CpGs for CVD traits by Mendelian randomization analysis. Further integrating gene expression data reveals evidence of cis CpG-transcript pairs causally linked to CVD. In addition, we identify 22 trans-meQTL hotspots each targeting more than 30 CpGs and find that trans-meQTL hotspots appear to act in cis on expression of nearby transcriptional regulatory genes. Our findings provide a powerful meQTL resource and shed light on DNA methylation involvement in human diseases.

12.
Trials ; 20(1): 538, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464626

RESUMO

BACKGROUND: Henoch-Schönlein purpura nephritis (HSPN) is the most common secondary glomerular disease in children. Currently, the treatment for HSPN is always selected based on the Kidney Disease Improving Global Outcomes guidelines; however, this approach may lead to undertreatment, especially in patients with persistent proteinuria that does not reach nephrotic levels and/or hematuria and those with a pathological classification between grades 1 and 3 according to the International Study of Kidney Disease in Children. This study was performed to evaluate the curative effect and safety of a traditional Chinese medicine (TCM) integrated treatment program in this type of HSPN. METHODS: This multicenter, open-label, large-sample, randomized controlled trial was performed in China and included 500 children with HSPN exhibiting mild pathological patterns. The treatment group to control group ratio was 2:1, and each group was further stratified into two types, light and heavy, according to urinary protein quantification and pathological type. The treatment group received tripterygium glycosides (TGs), tanshinone IIa sodium sulfonate injection, and Chinese herbs selected based on syndrome differentiation in TCM. The heavy and light subgroups received treatment courses and dosages of TG. In the control groups, the light group received benazepril hydrochloride tablets, low molecular weight heparin calcium injection, dipyridamole tablets, and a Chinese medicine placebo, while the heavy group received the same treatment plus prednisone. All groups were treated for 3 months and then followed up for 9 months. The efficacy and safety of the treatments were then evaluated among the groups. DISCUSSION: Currently, few treatments are available for HSPN patients with mild pathological patterns indicating light to moderate proteinuria and/or hematuresis. In this large-sample study, we provide a new approach for HSPN that includes an integrated treatment program that incorporates TCM. TRIAL REGISTRATION: Clinical Trials.gov, NCT03591471 . Re-registered on 19 July 2018.

13.
Zhonghua Wei Zhong Bing Ji Jiu Yi Xue ; 31(7): 811-814, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31441401

RESUMO

OBJECTIVE: A multicenter blinded randomized controlled trial (RCT) was conducted in accordance with international clinical trial standards to evaluate the efficacy and safety of Xuebijing injection in the treatment of severe community-acquired pneumonia (SCAP) under strict quality control condition. This article aims to illustrate key contents of the design ideas and implementation process of the RCT of Xuebijing injection in the treatment of SCAP, including the selection of research objects, design, implementation, and insights, etc., share experience with researchers of the respiratory and critical care, and provide reference for future studies in critical care.


Assuntos
Infecções Comunitárias Adquiridas/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Pneumonia/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Humanos
14.
BMJ Open ; 9(8): e028664, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31467049

RESUMO

INTRODUCTION: Sepsis is a major challenge with high incidence and is associated with high mortality worldwide. Current management of sepsis remains mainly supportive except for treatment with antibiotics. Both basic research and clinical investigation have shown that the Chinese herbal-derived therapeutic Xuebijing (XBJ) injection is beneficial for patients with sepsis. However, the quality of evidence supporting the therapeutic use of XBJ in sepsis is limited. The aim of this trial is to evaluate the Efficacy of Xuebijing Injection for Sepsis, compared with a placebo, on the outcome of patients with sepsis in the intensive care unit (ICU). METHODS AND ANALYSIS: In this multicentre, blinded randomised controlled trial, we are recruiting a total of 1800 subjects who met Sepsis 3.0 criteria. Subjects will be randomised (1:1) to receive XBJ, every 12 hours for 5 days or a matching placebo and usual care. The primary outcome is 28 days all-cause mortality. Secondary outcomes will be the improvement of Sequential Organ Failure Assessment scores, the improvement of the Acute Physiology and Chronic Health Evaluation II score, duration of mechanical ventilation, mortality in ICU and duration of stay in the ICU. Investigators, participants and statisticians will be blinded to the allocated treatment. ETHICS AND DISSEMINATION: This trial has been approved by all ethics committees of the centres that will participate in this trial. The findings of the study will be disseminated in peer-reviewed journals and present at conferences. Once this study is complete, the results of this trial may help provide evidence-based recommendations for complementary therapeutic options for patients with sepsis. TRIAL REGISTRATION NUMBER: NCT03238742 and ChiCTR-IPR-17012713.

15.
Mol Cell ; 75(6): 1229-1242.e5, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31377117

RESUMO

Interferon gamma (IFN-γ), critical for host defense and tumor surveillance, requires tight control of its expression. Multiple cis-regulatory elements exist around Ifng along with a non-coding transcript, Ifng-as1 (also termed NeST). Here, we describe two genetic models generated to dissect the molecular functions of this locus and its RNA product. DNA deletion within the Ifng-as1 locus disrupted chromatin organization of the extended Ifng locus, impaired Ifng response, and compromised host defense. Insertion of a polyA signal ablated the Ifng-as1 full-length transcript and impaired host defense, while allowing proper chromatin structure. Transient knockdown of Ifng-as1 also reduced IFN-γ production. In humans, discordant expression of IFNG and IFNG-AS1 was evident in memory T cells, with high expression of this long non-coding RNA (lncRNA) and low expression of the cytokine. These results establish Ifng-as1 as an important regulator of Ifng expression, as a DNA element and transcribed RNA, involved in dynamic and cell state-specific responses to infection.

16.
Immunity ; 51(4): 682-695.e6, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31353223

RESUMO

Innate lymphocytes maintain tissue homeostasis at mucosal barriers, with group 2 innate lymphoid cells (ILC2s) producing type 2 cytokines and controlling helminth infection. While the molecular understanding of ILC2 responses has advanced, the complexity of microenvironmental factors impacting ILC2s is becoming increasingly apparent. Herein, we used single-cell analysis to explore the diversity of gene expression among lung lymphocytes during helminth infection. Following infection, we identified a subset of ILC2s that preferentially expressed Il5-encoding interleukin (IL)-5, together with Calca-encoding calcitonin gene-related peptide (CGRP) and its cognate receptor components. CGRP in concert with IL-33 and neuromedin U (NMU) supported IL-5 but constrained IL-13 expression and ILC2 proliferation. Without CGRP signaling, ILC2 responses and worm expulsion were enhanced. Collectively, these data point to CGRP as a context-dependent negative regulatory factor that shapes innate lymphocyte responses to alarmins and neuropeptides during type 2 innate immune responses.

17.
Orphanet J Rare Dis ; 14(1): 160, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31262329

RESUMO

BACKGROUND: There are many public health issues to resolve regarding rare diseases, including a lack of data from large-scale studies. The objective of this study was to explore fundamental data for a list of rare diseases in China, based on a hospitalization summary reports (HSRs) database. The Target Rare Diseases List (TRDL) 2017 was generated using an expert consensus method in which experts listed diseases according to research priorities. Using codes of the 10th revision of the International Statistical Classification of Diseases and Related Health Problems (ICD-10) and key search terms of rare diseases in English and Chinese, data were obtained from HSRs of 96 hospitals, covering a population of over 15 million in China from 2014 to 2015. We extracted and analyzed information on demographics, hospitalizations, and readmissions. RESULTS: A total 281 rare diseases were included in the TRDL 2017. Altogether, 106,746 hospitalizations for a rare disease were captured from 1 January 2014 to 31 December 2015, accounting for 0.69% of inpatients during the same period. The top 10 rare diseases with most cases on the TRDL 2017 were thalassemia, idiopathic pulmonary arterial hypertension, pulmonary Langerhans cell histiocytosis, moyamoya disease, motor neuron disease, idiopathic pulmonary fibrosis, systemic sclerosis, hepatolenticular degeneration, coarctation of the aorta, and transposition of the great arteries. Among the 24 cities in the database, the five cities with the most types of the rare disease were Beijing, Changsha, Guangzhou, Shanghai, and Chengdu, with 191, 162, 143, 141, and 133 types, respectively. The five cities with most cases of the 281 rare diseases were Beijing, Guangzhou, Shanghai, Nanning, and Chengdu. The age distribution of rare diseases was 52% for the age group 25-64 years, and 27% of cases in the age group of 0-14 years were among children. The 10 highest readmission rates ranged from 35 to 65%. CONCLUSIONS: This study provided the TRDL 2017 and descriptive analysis of 281 rare diseases in a hospitalized population. Our study reveals important fundamental information that will be useful in national policy making and legislation; registry implementation; and diagnosis, treatment, and prevention of rare diseases in China.

18.
Epigenetics ; : 1-16, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31282290

RESUMO

DNA methylation (DNAm) and microRNAs (miRNAs) have been implicated in a wide-range of human diseases. While often studied in isolation, DNAm and miRNAs are not independent. We analyzed associations of expression of 283 miRNAs with DNAm at >400K CpG sites in whole blood obtained from 3565 individuals and identified 227 CpGs at which differential methylation was associated with the expression of 40 nearby miRNAs (cis-miR-eQTMs) at FDR<0.01, including 91 independent CpG sites at r2 < 0.2. cis-miR-eQTMs were enriched for CpGs in promoter and polycomb-repressed state regions, and 60% were inversely associated with miRNA expression. Bidirectional Mendelian randomization (MR) analysis further identified 58 cis-miR-eQTMCpG-miRNA pairs where DNAm changes appeared to drive miRNA expression changes and opposite directional effects were unlikely. Integration of genetic variants in joint analyses revealed an average partial between cis-miR-eQTM CpGs and miRNAs of 2% after conditioning on site-specific genetic variation, suggesting that DNAm is an important epigenetic regulator of miRNA expression. Finally, two-step MR analysis was performed to identify putatively causal CpGs driving miRNA expression in relation to human complex traits. We found that an imprinted region on 14q32 that was previously identified in relation to age at menarche is enriched with cis-miR-eQTMs. Nine CpGs and three miRNAs at this locus tested causal for age at menarche, reflecting novel epigenetic-driven molecular pathways underlying this complex trait. Our study sheds light on the joint genetic and epigenetic regulation of miRNA expression and provides insights into the relations of miRNAs to their targets and to complex phenotypes.

19.
Int J Mol Sci ; 20(14)2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31315232

RESUMO

Biomedical imaging modalities in clinical practice have revolutionized oncology for several decades. State-of-the-art biomedical techniques allow visualizing both normal physiological and pathological architectures of the human body. The use of nanoparticles (NP) as contrast agents enabled visualization of refined contrast images with superior resolution, which assists clinicians in more accurate diagnoses and in planning appropriate therapy. These desirable features are due to the ability of NPs to carry high payloads (contrast agents or drugs), increased in vivo half-life, and disease-specific accumulation. We review the various NP-based interventions for treatments of deep-seated tumors, involving "seeing better" to precisely visualize early diagnosis and "going deeper" to activate selective therapeutics in situ.

20.
J Orthop Surg Res ; 14(1): 226, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31324193

RESUMO

BACKGROUND: Avascular necrosis of the femoral head (ANFH) is a severe complication after high-dose glucocorticoid (GC) administration. The pathogenesis of GC-induced ANFH remains unclear. Though the important role of endothelial progenitor cells (EPCs) in the progression of GC-induced ANFH has been noticed, the effects of GCs on EPCs and the underlying mechanism still need further study. METHODS: Circulating EPCs were obtained from the peripheral blood of ANFH patients and healthy controls by Ficoll-density gradient centrifugation. CD133+CD34+ cells with DiI-Ac-LDL uptake and FITC-UEA-1 binding were considered as EPCs. Number and functions of EPCs were analyzed by flow cytometry, chemotaxis assay, and tube formation assay. EPCs from healthy controls were also treated by different concentrations of methylprednisolone and prednisolone in vitro, and cell growth and angiogenic function were evaluated. Expression of CXCR7 and its downstream Akt/GSK-3ß/Fyn pathway were also analyzed by western blots after cells treated by methylprednisolone in vitro. RESULTS: The number and functions of EPCs in patients with GC-induced ANFH were significantly decreased. In vitro study showed for the first time that except extremely high concentrations, low to medium concentrations of GCs did not have significant effects on EPCs' growth. Methylprednisolone and prednisolone both inhibited angiogenesis of EPCs even at low concentrations. Mechanism studies found CXCR7 was downregulated in EPCs after methylprednisolone treatment in vitro. Expression and phosphorylation of Akt and GSK-3ß were also decreased with an upregulation of Fyn expression after steroid treatment. CONCLUSIONS: Our study showed that GC-induced ANFH patients have reduced the number and impaired functions of circulating EPCs. GCs did not show a significant effect on the growth of EPCs in vitro except extremely high concentrations of GCs. However, GCs significantly impaired EPC angiogenic function in vitro, even at low concentrations. Our study also suggested that downregulation of CXCR7 and its downstream Akt/GSK-3ß/Fyn pathway in EPCs might be a novel mechanism of how GCs suppress EPCs' angiogenesis.

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