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1.
J Chem Phys ; 151(8): 085102, 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31470725

RESUMO

In recent years, there has been a growing interest to quantify the energy landscape that governs ribosome dynamics. However, in order to quantitatively integrate theoretical predictions and experimental measurements, it is essential that one has a detailed understanding of the associated diffusive properties. Here, all-atom explicit-solvent simulations (50 µs of aggregate sampling) predict that the diffusion coefficient of a tRNA molecule will depend on its position within the ribosome. Specifically, during aa-tRNA accommodation (i.e., the process by which tRNA enters the ribosome), the apparent diffusion coefficient decreases by approximately an order of magnitude. By comparing these to values obtained with an energetically "smooth" model, we show that the observed nonuniform behavior likely arises from electrostatic and solvation interactions between the tRNA and ribosome. These calculations also reveal the hierarchical character of ribosomal energetics, where steric interactions induce a large-scale free-energy barrier, and short-scale roughness determines the rate of diffusive movement across the landscape.

2.
Glob Chang Biol ; 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31479577

RESUMO

Subsoil contains more than half of soil organic carbon (SOC) globally and is conventionally assumed to be relatively unresponsive to warming compared to the topsoil. Here we show substantial changes in carbon allocation and dynamics of the subsoil but not topsoil in the Qinghai-Tibetan alpine grasslands over 5 years of warming. Specifically, warming enhanced the accumulation of newly synthesized (14 C-enriched) carbon in the subsoil slow-cycling pool (silt-clay fraction) but promoted the decomposition of plant-derived lignin in the fast-cycling pool (macroaggregates). These changes mirrored an accumulation of lipids and sugars at the expense of lignin in the warmed bulk subsoil, likely associated with shortened soil freezing period and a deepening root system. As warming is accompanied by deepening roots in a wide range of ecosystems, root-driven accrual of slow-cycling pool may represent an important and overlooked mechanism for a potential long-term carbon sink at depth. Moreover, given the contrasting sensitivity of SOC dynamics at varied depths, warming studies focusing only on surface soils may vastly misrepresent shifts in ecosystem carbon storage under climate change. This article is protected by copyright. All rights reserved.

3.
Biomolecules ; 9(9)2019 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-31480279

RESUMO

Cold stress can induce neuroinflammation in the hippocampal dentate gyrus (DG), but the mechanism underlying neuronal apoptosis induced by cold stress is not well-understood. To address this issue, male and female C57BL/6 mice were exposed to a temperature of 4 °C for 3 h per day for 1 week, and glial cell activation, neuronal apoptosis, and neuroinflammation were evaluated by western blotting, immunofluorescence, terminal deoxynucleotidyl transferase 2'-deoxyuridine 5'-triphosphate (dUTP) nick end labeling, Nissl staining, and immunohistochemistry. Additionally, BV2 cells were treated with different concentrations of cortisol (CORT) for 3 h to mimic stress and molecular changes were assessed by western blotting, immunofluorescence, and co-immunoprecipitation. We found that excess CORT activated glial cells and increased neuroinflammation in the DG of mice exposed to cold temperatures, which was associated with increased acetylation and nuclear factor-κB signaling. These effects were mediated by the acetylation of lysine 9 of histone 3 and lysine 310 of p65, which resulted in increased mitogen-activated protein kinase phosphorylation, nuclear translocation of p65, microglia activation, and acetylation of high-mobility group box 1. Neuroinflammation was more severe in male compared to female mice. These findings provide new insight into the mechanisms of the cold stress response, which can inform the development of new strategies to combat the effects of hypothermia.

4.
Int J Mol Sci ; 20(18)2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31510090

RESUMO

The negative association between psychological stress and male fertility has been known for many years. This study was aimed at (i) identifying spermatogenesis impairment induced by psychological stress in rats and (ii) exploring the role of glucocorticoid receptor (GR) signaling in these adverse effects (if they exist). Male Sprague Dawley rats were exposed to a six-week period of unpredictable chronic mild stress (uCMS) along with cotreatment of GR antagonist RU486 (1 mg/kg/day). Testicular damage was assessed by testicular pathological evaluation, epididymal sperm concentration, serum testosterone levels, testicular apoptotic cell measurements, and cell cycle progression analyses. Rats in the uCMS group had decreased levels of serum testosterone and decreased epididymal sperm concentration. The uCMS-treated rats also had decreased numbers of spermatids and increased levels of apoptotic seminiferous tubules; additionally, cell cycle progression of spermatogonia was arrested at the G0/G1 phase. Furthermore, uCMS exposure caused an increase in serum corticosterone level and activated GR signaling in the testes including upregulated GR expression. RU486 treatment suppressed GR signaling and alleviated the damaging effects of stress, resulting in an increased epididymal sperm concentration. Overall, this work demonstrated for the first time that the activation of GR signaling mediates stress-induced spermatogenesis impairment and that this outcome is related to cell apoptosis and cell cycle arrest in germ cells.

5.
Int J Cardiol ; 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31399301

RESUMO

BACKGROUND: Vascular aging has profound effects on cardiovascular diseases. Endothelial to mesenchymal transition (EndMT) is defined as the acquisition of mesenchymal characteristics by endothelial cells (ECs) and has been found induced in a model of ECs aging. However, whether EndMT occurs during aging in vivo, the functional significance of EndMT on vascular biology and the underlying mechanisms remain unknown. METHODS AND RESULTS: In this study, we examined the vascular ECs from young (2 months old) and old (18 months old) mice, and demonstrated that aged ECs underwent EndMT. Moreover, the transwell assay showed that EndMT process was accompanied by increased endothelial permeability. It was found that sirtuin 6 (SIRT6), a nicotinamide adenine dinucleotide+ (NAD+)-dependent histone deacetylase, was down-regulated during ECs aging. Knockdown of SIRT6 in young ECs could induce EndMT. Next, we identified five long non-coding RNAs that are enriched in ECs for downstream effector of SIRT6; only metastasis associated lung adenocarcinoma transcript 1 (MALAT1) was significantly up-regulated in aged ECs. Knockdown of SIRT6 could increase MALAT1 levels. Furthermore, the ChIP assay and luciferase reporter gene assay confirmed that SIRT6 bound directly to the promoter region of MALAT1 and suppressed MALAT1 expression. Finally, we demonstrated that MALAT1 mediated aging-induced EndMT through increasing Snail expression. CONCLUSION: Our study provides in vivo evidence that ECs undergo EndMT during vascular aging, which increases endothelial permeability. SIRT6-mediated transcriptional suppression of MALAT1 is a key mechanism for EndMT. Manipulating EndMT may be considered as a new therapeutic strategy for retarding aging-associated vascular diseases.

6.
Aging (Albany NY) ; 11(15): 5757-5768, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31413207

RESUMO

In this study, we investigated the localization, morphological features and cellular interactions of telocytes in the rat testicular interstitium. Transmission electron microscopy (TEM) and immunohistochemical and immunofluorescence analyses of the rat testicular interstitium showed a distinct layer of telocytes surround the seminiferous tubules along with inner layer of peritubular myoid cells. The majority of the telocytes were made up of a small cell body and moniliform prolongations that contained mitochondria and secretory vesicles. Some other telocytes were observed possessing large cell bodies. Within the testicular interstitium, the telocytes formed a network connecting peritubular myoid cells, Leydig cells as well as blood vessels. Immunohistochemical and double immunofluorescence analyses showed that rat testicular telocytes express CD34 and PDGFRα, but are negative for vimentin and α-SMA. Our findings demonstrate the presence of telocytes in the rat testicular interstitium. These cells interact with peritubular myoid cells, seminiferous tubules, Leydig cells and blood vessels via long telopode extensions, which suggests their vital role in the intercellular communication between different cell types within the rat testis.

7.
J Exp Clin Cancer Res ; 38(1): 343, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391070

RESUMO

BACKGROUND: Kidney Renal Clear Cell Carcinoma (KIRC) accounts for 75% of all renal cancers. Previous study had conflict evidences regarding NR1B2 role in cancer, and its expression and biological role in KIRC remained unclear. Our aims were to characterize the role of NR1B2 in KIRC. METHODS: NR1B2 expression in TCGA database were analyzed. Clinical KIRC samples were examined by RT-PCR, western blot and tissue microarray (TMA). The relationship between NR1B2 expression and the clinical characteristics were evaluated. KIRC cell line were stably overexpressed NR1B2 or with an NR1B2 knocked down using lentivirus system. The cells were analyzed by migration and invasion assay, then injected into nude mice to assess tumor growth and metastasis. EMT marker expression and LATS 1/2-YAP pathway demonstration were detected by the TCGA database and western blot. RESULTS: The expression of NR1B2 in KIRC was significantly down-regulated in the TCGA database and our clinical samples. Moreover, NR1B2 expression negatively correlated with tumor stage and positively correlated with overall and disease-free survival rate. Univariate and multivariate analyses indicated the expression level of NR1B2 could be used as an independent factor for predicting the prognosis of KIRC. Overexpression NR1B2 significantly inhibited and knockdown NR1B2 markedly promoted KIRC cell invasion and metastasis both in vitro and in vivo. Mechanistic investigations revealed that NR1B2 might be a tumor suppressor to inhibit EMT through the LATS1/2-YAP pathway. CONCLUSIONS: our results defined NR1B2 as a tumor suppressor in KIRC that restricted EMT by the LATS1/2-YAP pathway.

8.
Clin Nephrol ; 2019 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-31448719

RESUMO

OBJECTIVE: To study the effects of early continuous veno-venous hemofiltration (CVVH) on organ function and intra-abdominal pressure (IAP) in severe acute pancreatitis (SAP) patients with abdominal compartment syndrome (ACS). MATERIALS AND METHODS: 48 SAP patients with ACS were included in this study. Among them, 37 patients, receiving both conventional treatment and hemofiltration therapy in the ICU, were regarded as the treatment group, and the rest, receiving only conventional treatment, were regarded as the control group. Symptoms, signs, and adverse reactions of both groups were observed and recorded during treatments. Serum and urine amylase, liver and kidney function, C-reactive protein, and intra-abdominal pressure of the patients were detected before and on days 1, 2, 3, 4, 5, and 6 after treatment. RESULTS: 1. Symptoms and signs in the treatment group disappeared quickly, and their hospitalization time was significantly shorter than those of control group (p < 0.05). 2. After treatment, on days 1, 2, 3, 4, 5, and 6, patients' serum and urine amylase levels, C-reactive protein, and intra-abdominal pressure were significantly lower, and liver and kidney function was significantly better than those of the control group (p < 0.05). CONCLUSION: Early hemofiltration in SAP with ACS can effectively reduce intra-abdominal pressure, improve symptoms, accelerate liver and renal function recovery, avoid multiple organ failure and decrease mortality rate.
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9.
J Med Food ; 2019 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-31460816

RESUMO

Lactoferrin (LF) is a multifunctional glycoprotein and has beneficial effects on the regulation of lipid metabolism. However, whether LF supplementation alleviates the development of atherosclerosis (AS) remains unclear. In the present study, all of 48 male Apolipoprotein E-/- mice were fed with high-fat diet with 1.25% added cholesterol and divided to four treatment groups with either distilled water (HFCD), LF solutions at 2 mg/mL (low LF), 10 mg/mL (middle LF or MLF), or 20 mg/mL (high LF or HLF) for 12 weeks. Oral glucose tolerance tests (OGTT) were performed at weeks 0, 4, 8, and 12. At the end of the experiment, lipids in serum, liver, and feces were determined. The livers, whole aortas, and aortic sinuses were pathologically examined. The protein expression of factors related to cholesterol synthesis, absorption, and excretion were detected through western blot. No significant difference in body weight, food intake, and OGTT was observed among the four groups. Compared with the HFCD group, the MLF and HLF groups had significantly decreased serum and hepatic cholesterol levels and significantly increased fecal cholesterol contents. LF alleviated the hepatic steatosis and lipid droplet, especially in the MLF group. LF also significantly decreased the average lesion areas in the whole aorta, especially in the MLF group. On the other hand, LF downregulated hepatic protein expression of HMG-CoA reductase (the rate-limiting enzyme in cholesterol synthesis) and upregulated cholesterol 7-alpha hydroxylase (the rate-limiting enzyme in bile acid synthesis from cholesterol). LF also downregulated the intestinal expression of Niemann-Pick C1-like 1 protein, which is known to bind to a critical mediator of cholesterol absorption. In conclusion, LF supplementation alleviates the AS in mice on HFCD likely by reducing the synthesis and absorption of cholesterol and increasing cholesterol excretion.

10.
Methods Mol Biol ; 2022: 129-151, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31396902

RESUMO

Over the last 20 years, the application of structure-based (Go-like) models has ranged from protein folding with coarse-grained models to all-atom representations of large-scale molecular assemblies. While there are many variants that may be employed, the common feature of these models is that some (or all) of the stabilizing energetic interactions are defined based on the knowledge of a particular experimentally obtained conformation. With the generality of this approach, there was a need for a versatile computational platform for designing and implementing this class of models. To this end, the SMOG 2 software package provides an easy-to-use interface, where the user has full control of the model parameters. This software allows the user to edit XML-formatted files in order to provide definitions of new structure-based models. SMOG 2 reads these "template" files and maps the interactions onto specific structures, which are provided in PDB format. The force field files produced by SMOG 2 may then be used to perform simulations with a variety of popular molecular dynamics suites. In this chapter, we describe some of the key features of the SMOG 2 package, while providing examples and strategies for applying these techniques to complex (often large-scale) molecular assemblies, such as the ribosome.

11.
Phys Rev Lett ; 122(25): 253201, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31347860

RESUMO

Stimulated Raman adiabatic passage (stirap) allows efficiently transferring the populations between two discrete quantum states and has been used to prepare molecules in their rovibrational ground state. In realistic molecules, a well-resolved intermediate state is usually selected to implement the resonant stirap. Because of the complex molecular level structures, the detuned stirap always coexists with the resonant stirap and may cause unexpected interference phenomenon. However, it is generally accepted that the detuned stirap can be neglected if compared with the resonant stirap. Here we report on the first observation of interference between the resonant and detuned stirap in the adiabatic creation of ^{23}Na^{40}K ground-state molecules. The interference is identified by observing that the number of Feshbach molecules after a round-trip stirap oscillates as a function of the hold time, with a visibility of about 90%. This occurs even if the intermediate excited states are well resolved, and the single-photon detuning of the detuned stirap is about 1 order of magnitude larger than the linewidth of the excited state and the Rabi frequencies of the stirap lasers. Moreover, the observed interference indicates that if more than one hyperfine level of the ground state is populated, the stirap prepares a coherent superposition state among them, but not an incoherent mixed state. Further, the purity of the hyperfine levels of the created ground state can be quantitatively determined by the visibility of the oscillation.

12.
Eur J Immunol ; 2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31348521

RESUMO

Recently, microRNAs (miRNAs) have been reported to play crucial roles in immune responses and other biological processes, but the role of miR-181a in myasthenia gravis (MG) has been relatively less studied. We found that miR-181a was downregulated in the peripheral blood mononuclear cells (PBMCs) of MG patients and was associated with QMGs and anti-AChR Ab levels. In vitro experiments indicated that miR-181a was involved in the modulation of CD4+ T cell activation and plasticity and that miR-181a decreased the expression level of the Th1-related transcription factor T-bet and the Th17-related transcription factor RORγt. In the in vivo experiment, miR-181a treatment alleviated experimental autoimmune myasthenia gravis (EAMG) symptoms and affected both CD4+ T cell differentiation and the production of anti-AChR antibodies. Moreover, in this study, we also found that IL-2 was regulated by miR-181a and that its expression level showed a strong negative correlation with miR-181a levels in MG patients. To illustrate that the expression levels of both IL-2 and miR-181a were sensitive to immunomodulatory therapy treatment in MG, we found that IL-2 and miR-181a were correlated with clinical severity. These findings demonstrate that miR-181a can contribute to the pathogenesis of MG by regulating IL-2 expression. This article is protected by copyright. All rights reserved.

13.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 44(5): 549-554, 2019 May 28.
Artigo em Chinês | MEDLINE | ID: mdl-31303619

RESUMO

OBJECTIVE: To analyze the clinical and image features for 12 patients of cerebral autosomal dominant arteriopathy with subcortical infarct and leucoencephalopathy (CADASIL).
 Methods: A total of 12 CADASIL patients were collected in Xiangya Hospital of Central South University from January 2013 to December 2018. The clinical manifestation, risk factors, MRI imaging data and NOTCH3 mutations were analyzed retrospectively.
 Results: The mean age of 12 patients was (47.25±9.49) years. The clinical manifestation was most common in cognitive impairment (75%) and stroke events (58.3%), and 2 cases showed cerebral hemorrhage. Migraine was only seen in 25% patients. All MRI showed white matter hyperintensity (WMH), lacune and enlarged perivascular space (PVS). WMH mainly occurred in the frontal parietal lobe (100%), temporal lobe (83.3%), external capsule (66.7%), occipital lobe (41.6%), callosum 41.6% and the temporal pole (33.3%), while lacune mainly appeared in frontal lobe (91.6%), parietal lobe(83.3%), temporal lobe(66.7%), basal ganglia (66.7%), brain stem (41.6%), occipital lobe (33.3%), cerebellum (8.3%). Enlarged PVS located in the basal ganglia (100%), partly under the cortex (45.4%). WMH of the patient with intracerebral hemorrhage was mild (Fezakas score 1-2), which was not found in external capsule. 16.7% of the patients had intracranial arterial stenosis. In 12 patients, 8 different Notch3 mutations were detected. The c1013G>c p.(Cys338Ser) located in exon 6, which was a new pathogenic mutation of CADASIL.
 Conclusion: The patients with cerebral hemorrhage have mild WMH and specific genotype, indicating that the clinical characteristics of CADASIL with cerebral hemorrhage may be related to image features and genotype.


Assuntos
CADASIL , Infarto Cerebral , Leucoencefalopatias , Adulto , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Lobo Temporal
14.
Carbohydr Polym ; 222: 114974, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320071

RESUMO

Stable hydrogels with a mechanically strong matrix microenvironment are favorable biomaterials for three-dimensional cell culture. Acidic collagen solution is commonly combined with chemical crosslinkers for rapid network formation. Herein, dialdehyde carboxymethyl cellulose (DCMC) was selected as an optimal crosslinking reagent for its excellent biocompatibility and suitable chemical reactivity. Both shielding of electrostatic attractions between these two oppositely charged biomaterials and obtaining concentrated collagen solution were achieved using a novel biphasic acetic acid /1-ethyl-3-methylimidazolim acetate (AA/[EMIM][Ac]) solvent system. Hydrogel composites containing more crosslinks were obtained by increasing collagen concentrations (5-25 mg/mL), as confirmed by the improved mechanical properties, thermal denaturation temperature, anti-enzymatic ability and compact microstructure. Moreover, cell proliferation assay demonstrated that all the obtained DCMC-crosslinked collagen hydrogel composites ensures commendable biocompatibility. This study provides a promising strategy for manipulating stable and biocompatible hydrogel composites by blending concentrated collagen solution with DCMC in a biphasic solvent system.

15.
Artigo em Inglês | MEDLINE | ID: mdl-31339772

RESUMO

Ischemia-reperfusion-induced acute kidney injury (IR-AKI) favors mitochondrial permeability transition pore (mPTP) opening and subsequent cell death. Cyclophilin D (CypD) is an essential component of the mPTP, and recent findings implicate the p53-CypD complex in cell death. To evaluate the role of p53-CypD following IR-AKI, we tested the hypothesis that the p53-CypD complex mediates renal tubular cell apoptosis in IR-AKI via mPTP opening. The expression of p53 and cleaved caspase-3 was significantly increased in rats subjected to IR-AKI compared with the normal control and sham-operated control. The underlying mechanisms were determined using an in vitro model of ATP-depletion. The inhibition of mPTP opening using the CypD inhibitor cyclosporin A or a siRNA for p53 in ATP-depleted HK-2 cells prevented mitochondrial membrane depolarization and reduced apoptosis. Furthermore, p53 binds to CypD in ATP-depleted HK-2 cells. These results suggest that the p53-CypD complex mediates renal tubular cell apoptosis in IR-AKI via mPTP opening.

16.
Mol Med Rep ; 20(2): 1613-1620, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257491

RESUMO

Renal tubular epithelial cell apoptosis is an important pathological mechanism of septic acute kidney injury (AKI). Endotoxin, also known as lipopolysaccharide (LPS), has a key role in septic AKI and can directly induce tubular epithelial cell apoptosis. The upregulation of receptor­interacting protein kinase 3 (RIPK3) in tubular epithelial cells has been reported in septic AKI, with RIPK3 mediating apoptosis in several cell types. In the present study, the effect of RIPK3 on endotoxin­induced AKI was investigated in mouse tubular epithelial cell apoptosis in vitro and in vivo. It was found that the expression of RIPK3 was markedly increased in endotoxin­induced AKI. Endotoxin­induced AKI and tubular epithelial cell apoptosis could be attenuated by GSK'872, a RIPK3 inhibitor. LPS stimulation also upregulated RIPK3 expression in tubular epithelial cells in a time­dependent manner. Both RIPK3 inhibitor and small interfering RNA (siRNA) targeting RIPK3 reduced LPS­induced tubular epithelial cell apoptosis in vitro. The expression of the proapoptotic protein Bax was induced by LPS and reversed by GSK'872 or RIPK3­siRNA. The present study revealed that RIPK3 mediated renal tubular cell apoptosis in endotoxin­induced AKI. RIPK3 may be a potential target for the prevention of renal tubular cell apoptosis in endotoxin­induced AKI.

17.
Aging (Albany NY) ; 11(13): 4641-4653, 2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-31305258

RESUMO

In this study, we investigated the neural changes and their relationships with interstitial cells (ICs) in the rumen of pre-weaning goats by transmission electron microscopy, western blot and immunofluorescence (antibody: general neuronal marker-Protein Gene Product (PGP9.5)/ IC marker-vimentin). The immunofluorescence results showed that PGP9.5-positive reaction was widely distributed in neuronal soma (NS) and nerve fibre (NF). The NSs were observed in the ganglia of the myenteric plexus (MP) but not in the submucosal plexus. The mean optical density (MOD) of the whole of PGP9.5-positive nerves and the protein expression level of PGP.5 in the rumen wall both decreased significantly with age. However an obvious increase MOD of PGP.5-positive NFs within the rumen epithelium were observed. In the MP, the nerves and ICs were interwoven to form two complex networks that gradually tightened with age. Furthermore, NSs and nerve trunks were surrounded by a ring-boundary layer consisting of several ICs that became physically closer with aging. Moreover, ICs were located nearby NFs within the ML, forming connections between ICs, smooth muscle cells and axons. This study describes the pattern of neural distribution and its association with ICs in the developing rumen which shed light on the postpartum development of ruminants.

18.
Nanoscale ; 11(28): 13484-13493, 2019 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-31289802

RESUMO

In this study, a structure of large-area orderly-arranged SiO2@Si core-shell nanoparticles decorated with Au nanoparticles was fabricated for surface-enhanced Raman spectroscopy (SERS). This hybrid structure features light confinement in the Si shells and a uniform distribution of localized electric hot spots. FDTD simulations were carried out to examine the near-field enhancement response of this structure. Results indicate that the strongly enhanced local electric field is attributed to the WGM-LSPR coupling, that is, the coupling of the whispering gallery mode (WGM) of Si nanoshells with the localized surface plasmon resonance (LSPR) of Au nanoparticles. The excitation of WGM comes primarily from the magnetic response of the Si shell with a minor modification by its electric response. The WGM-LSPR coupling of the structure is tunable through the change of geometric parameters of SiO2@Si particles. Raman scattering measurements were conducted on the samples fabricated, which agree well with the simulated results. The measured data gave a SERS G factor of ∼2 × 108 and showed highly sensitive and reproducible SERS signals of R6G with a high spatial uniformity on a 2 × 2 cm2 substrate consisting of an array of SiO2@Si (D = ∼220 nm/290 nm) particles whose outer surfaces were scattered with d = ∼20 nm Au particles.

19.
Photobiomodul Photomed Laser Surg ; 37(6): 349-355, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31188090

RESUMO

Objective: Photobiomodulation (PBM) can usefully promote wound healing and relieve pain via its biological effects, with a wide range of applications in clinical medicine. The aim of the present study was to investigate the effect of 660 and 830 nm PBM on orthodontic tooth movement. Background data: PBM is based on the biological effects of diode laser irradiation on tissues, promoting cell proliferation and activity. Materials and methods: An orthodontic force was applied to the upper right first molars exposed to a 660 and 830 nm PBM (LHH-500I; Beijing Long Hui Heng Medical Science and Technology Development Corporation) on days 0, 1, 2, 3, 4, 5, and 7 for 50 sec with power density of 0.1 W/cm2 (a beam area of 0.5 cm2, radiate power of 0.05 W), energy density of 5 J/cm2 within 14 days, and a control group with no laser irradiation. Tooth movement was analyzed using a stereomicroscope, the number of osteoclasts determined by tartrate-resistant acid phosphatase (TRAP), and the expression of bone remodeling factors evaluated by immunohistochemistry. Results: The expression of IL-1ß, RANKL, and OPG was significantly stimulated in the 660 and 830 nm groups. The expression of RANKL was significantly higher in the 660 nm group than in the 830 nm group on days 5 and 7; however, there was no significant difference in the expression of OPG and IL-1ß between the 660 and 830 nm groups on days 1, 2, 3, 4, 5, 7, and 14. On days 3 and 5, the number of osteoclasts in the 660 nm group was higher than that in the 830 nm group, and the difference was statistically significant. Tooth movement over 14 days was significantly higher in the 660 and 830 nm groups than in the control group, and there was no significant difference between the 660 and 830 nm groups finally. Conclusions: Both 660 and 830 nm can accelerate the orthodontic tooth movement and promote alveolar bone remodeling on the compression side. Although the difference of tooth movement over 14 days between the two groups was not statistically significant; however, 660 nm PBM to accelerate bone remodeling is stronger than 830 nm PBM at an early stage.

20.
Cell Death Dis ; 10(7): 476, 2019 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-31209210

RESUMO

Mesothelin (MSLN) is an attractive antigen for chimeric antigen receptor (CAR) T therapy and the epitope selection within MSLN is essential. In this study, we constructed two types of CARs targeting either region I of MSLN (meso1 CAR, also known as a membrane-distal region) or region III of MSLN (meso3 CAR, also known as a membrane-proximal region) using a modified piggyBac transposon system. We reported that, compared with meso1 CAR T cells, meso3 CAR T cells express higher levels of CD107α upon activation and produce increased levels of interleukin-2, TNF-α, and IFN-γ against multiple MSLN-expressing cancer cells in vitro. In a real-time cell analyzer system and a three-dimensional spheroid cancer cell model, we also demonstrated that meso3 CAR T cells display an enhanced killing effect compared with that of meso1 CAR T cells. More importantly, in a gastric cancer NSG mice model, meso3 CAR T cells mediated stronger antitumor responses than meso1 CAR T cells did. We further identified that meso3 CAR T cells can effectively inhibit the growth of large ovarian tumors in vivo. Collectively, our study provides evidences that meso3 CAR T-cell therapy performs as a better immunotherapy than meso1 CAR T-cell therapy in treating MSLN-positive solid tumors.

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