Quantitative dynamic contrast-enhanced parameters and intravoxel incoherent motion facilitate the prediction of TP53 status and risk stratification of early-stage endometrial carcinoma.

BACKGROUND: The aim of the study was to investigate the value of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) and intravoxel incoherent motion (IVIM) in differentiating TP53-mutant from wild type, low-risk from non-low-risk early-stage endometrial carcinoma (EC). PATIENTS AND METHODS: A total of 74 EC patients underwent pelvic MRI. Parameters volume transfer constant (Ktrans), rate transfer constant (Kep), the volume of extravascular extracellular space per unit volume of tissue (Ve), true diffusion coefficient (D), pseudo-diffusion coefficient (D*), and microvascular volume fraction (f) were compared. The combination of parameters was investigated by logistic regression and evaluated by bootstrap (1000 samples), receiver operating characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: In the TP53-mutant group, Ktrans and Kep were higher and D was lower than in the TP53-wild group; Ktrans, Ve, f, and D were lower in the non-low-risk group than in the low-risk group (all P < 0.05). In the identification of TP53-mutant and TP53-wild early-stage EC, Ktrans and D were independent predictors, and the combination of them had an optimal diagnostic efficacy (AUC, 0.867; sensitivity, 92.00%; specificity, 80.95%), which was significantly better than D (Z = 2.169, P = 0.030) and Ktrans (Z = 2.572, P = 0.010). In the identification of low-risk and non-low-risk early-stage EC, Ktrans, Ve, and f were independent predictors, and the combination of them had an optimal diagnostic efficacy (AUC, 0.947; sensitivity, 83.33%; specificity, 93.18%), which was significantly better than D (Z = 3.113, P = 0.002), f (Z = 4.317, P < 0.001), Ktrans (Z = 2.713, P = 0.007), and Ve (Z = 3.175, P = 0.002). The calibration curves showed that the above two combinations of independent predictors, both have good consistency, and DCA showed that these combinations were reliable clinical prediction tools. CONCLUSIONS: Both DCE-MRI and IVIM facilitate the prediction of TP53 status and risk stratification in early-stage EC. Compare with each single parameter, the combination of independent predictors provided better predictive power and may serve as a superior imaging marker.

Use of biexponential and stretched exponential models of intravoxel incoherent motion and dynamic contrast-enhanced magnetic resonance imaging to assess the proliferation of endometrial carcinoma.

Background: It is important to assess the proliferation of endometrial carcinoma (EC) noninvasively using imaging methods. This prospective diagnostic study investigated the value of biexponential and stretched exponential models of intravoxel incoherent motion (IVIM) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in predicting the Ki-67 status of EC. Methods: In all, 70 patients with EC underwent pelvic MRI. The diffusion coefficient (D), pseudo diffusion coefficient (D*), perfusion fraction (f), distributed diffusion coefficient (DDC), water molecular diffusion heterogeneity index (α), volume transfer constant (Ktrans), rate transfer constant (Kep), and volume of extravascular extracellular space per unit volume of tissue (Ve) were compared. The area under the receiver operating characteristic (ROC) curve (AUC) was used to quantify diagnostic efficacy. Multivariate logistic regression and bootstrap (1,000 samples) analyses were used to establish and evaluate, respectively, the optimal model to predict Ki-67 status. Results: D, Ktrans, and Kep were lower while α was higher in the high-proliferation group as compared with low-proliferation group (all P values<0.05). D and Kep were independent predictors of Ki-67 status in EC, and the combination of these parameters had optimal diagnostic efficacy (AUC =0.920; sensitivity 85.71%; specificity 89.29%), which was significantly better than that of D (AUC =0.753; Z=2.874; P=0.004), α (AUC =0.715; Z=3.505; P=0.001), Ktrans (AUC =0.808; Z=2.741; P=0.006), and Kep (AUC =0.832; Z=2.147; P=0.032) alone. The validation model showed good accuracy (AUC =0.882; 95% confidence interval 0.861-0.897) and consistency (C-statistic =0.902). D, Kep, Ktrans, and α showed a slightly negative (r=-0.271), moderately negative (r=-0.534), slightly negative (r=-0.409), and slightly positive (r=0.488) correlation with the Ki-67 index, respectively (all P values <0.05). Conclusions: IVIM- and DCE-MRI-derived parameters, including D, α, Ktrans, and Kep, were associated with Ki-67 status in EC, and the combination of D and Kep may serve as a superior imaging marker for the identification of low- and high-proliferation EC.

GATA6 triggers fibroblast activation and tracheal fibrosis through the Wnt/ß-catenin pathway.

Tracheal fibrosis is a key abnormal repair process leading to fatal stenosis, characterized by excessive fibroblast activation and extracellular matrix (ECM) deposition. GATA6, a zinc finger-containing transcription factor, is involved in fibroblast activation, while its role in tracheal fibrosis remains obscure. The present study investigated the potential role of GATA6 as a novel regulator of tracheal fibrosis. It was found that GATA6 and α-smooth muscle actin (α-SMA) were obviously increased in tracheal fibrotic granulations and in TGFß1-treated primary tracheal fibroblasts. GATA6 silencing inhibited TGFß1-stimulated fibroblast proliferation and ECM synthesis, promoted cell apoptosis, and inactivated Wnt/ß-catenin pathway, whereas GATA6 overexpression showed the reverse effects. SKL2001, an agonist of Wnt/ß-catenin signaling, restored collagen1a1 and α-SMA expression which was suppressed by GATA6 silencing. Furthermore, in vivo, knockdown of GATA6 ameliorated tracheal fibrosis, as manifested by reduced tracheal stenosis and ECM deposition. GATA6 inhibition in rat tracheas also impaired granulation proliferation, increased apoptosis, and inactivated Wnt/ß-catenin pathway. In conclusion, our findings indicate that GATA6 triggers fibroblast activation, cell proliferation, and apoptosis resistance in tracheal fibrosis via the Wnt/ß-catenin signaling pathway. Targeting GATA6 may represent a promising therapeutic approach for tracheal fibrosis.

Evaluation of Amide Proton Transfer-Weighted Imaging for Risk Factors in Stage I Endometrial Cancer: A Comparison With Diffusion-Weighted Imaging and Diffusion Kurtosis Imaging.

Background: Endometrial cancer (EC) is one of the most common gynecologic malignancies in clinical practice. This study aimed to compare the value of diffusion-weighted imaging (DWI), diffusion kurtosis imaging (DKI), and amide proton transfer-weighted imaging (APTWI) in the assessment of risk stratification factors for stage I EC including histological subtype, grade, stage, and lymphovascular space invasion (LVSI). Methods: A total of 72 patients with stage I EC underwent pelvic MRI. The apparent diffusion coefficient (ADC), mean diffusivity (MD), mean kurtosis (MK), and magnetization transfer ratio asymmetry (MTRasym at 3.5 ppm) were calculated and compared in risk groups with the Mann-Whitney U test or independent samples t-test. Spearman's rank correlation was applied to depict the correlation of each parameter with risk stratification. The diagnostic efficacy was evaluated with receiver operating characteristic (ROC) curve analysis and compared using the DeLong test. A multivariate logistic regression was conducted to explore the optimal model for risk prediction. Results: There were significantly greater MTRasym (3.5 ppm) and MK and significantly lower ADC and MD in the non-adenocarcinoma, stage IB, LVSI-positive, high-grade, and non-low-risk groups (all p < 0.05). The MK and MTRasym (3.5 ppm) were moderately positively correlated with risk stratification as assessed by the European Society for Medical Oncology (EMSO) clinical practice guidelines (r = 0.640 and 0.502, respectively), while ADC and MD were mildly negatively correlated with risk stratification (r = -0.358 and -0.438, respectively). MTRasym (3.5 ppm), MD, and MK were identified as independent risk predictors in stage I EC, and optimal predictive performance was obtained with their combinations (AUC = 0.906, sensitivity = 70.97%, specificity = 92.68%). The results of the validation model were consistent with the above results, and the calibration curve showed good accuracy and consistency. Conclusions: Although similar performance was obtained with each individual parameter of APTWI, DWI, and DKI for the noninvasive assessment of aggressive behavior in stage I EC, the combination of MD, MK, and MTRasym (3.5 ppm) provided improved predictive power for non-low-risk stage I EC and may serve as a superior imaging marker.

Nitric oxide-releasing polyurethane/S-nitrosated keratin mats for accelerating wound healing.

Nitric oxide (NO) plays an important role in wound healing, due to its ability to contract wound surfaces, dilate blood vessels, participate in inflammation as well as promote collagen synthesis, angiogenesis and fibroblast proliferation. Herein, keratin was first nitrosated to afford S-nitrosated keratin (KSNO). As a NO donor, KSNO was then co-electrospun with polyurethane (PU). These as-spun PU/KSNO biocomposite mats could release NO sustainably for 72 h, matching the renewal time of the wound dressing. Moreover, these mats exhibited excellent cytocompatibility with good cell adhesion and cell migration. Further, the biocomposite mats exhibited antibacterial properties without inducing severe inflammatory responses. The wound repair in vivo demonstrated that these mats accelerated wound healing by promoting tissue formation, collagen deposition, cell migration, re-epithelialization and angiogenesis. Overall, PU/KSNO mats may be promising candidates for wound dressing.

Nitric oxide-releasing poly(ε-caprolactone)/S-nitrosylated keratin biocomposite scaffolds for potential small-diameter vascular grafts.

Rapid endothelialization and regulation of smooth muscle cell proliferation are crucial for small-diameter vascular grafts to address poor compliance, thromboembolism, and intimal hyperplasia, and achieve revascularization. As a gaseous signaling molecule, nitric oxide (NO) regulates cardiovascular homeostasis, inhibits blood clotting and intimal hyperplasia, and promotes the growth of endothelial cells. Due to the instability and burst release of small molecular NO donors, a novel biomacromolecular donor has generated increasing interest. In the study, a low toxic NO donor of S-nitrosated keratin (KSNO) was first synthesized and then coelectrospun with poly(ε-caprolactone) to afford NO-releasing small-diameter vascular graft. PCL/KSNO graft was capable to generate NO under the catalysis of ascorbic acid (Asc), so the graft selectively elevated adhesion and growth of human umbilical vein endothelial cells (HUVECs), while inhibited the proliferation of human aortic smooth muscle cells (HASMCs) in the presence of Asc. In addition, the graft displayed significant antibacterial properties and good blood compatibility. Animal experiments showed that the biocomposite graft could inhibit thrombus formation and preserve normal blood flow via single rabbit carotid artery replacement for 1 month. More importantly, a complete endothelium was observed on the lumen surface. Taken together, PCL/KSNO small-diameter vascular graft has potential applications in vascular tissue engineering with rapid endothelialization and vascular remolding.

Comparison of Diffusion Kurtosis Imaging and Amide Proton Transfer Imaging in the Diagnosis and Risk Assessment of Prostate Cancer.

OBJECTIVES: This study aims to evaluate and compare the diagnostic value of DKI and APT in prostate cancer (PCa), and their correlation with Gleason Score (GS). MATERIALS AND METHODS: DKI and APT imaging of 49 patients with PCa and 51 patients with benign prostatic hyperplasia (BPH) were collected and analyzed, respectively. According to the GS, the patients with PCa were divided into high-risk, intermediate-risk and low-risk groups. The mean kurtosis (MK), mean diffusion (MD) and magnetization transfer ratio asymmetry (MTRasym, 3.5 ppm) values among PCa, BPH, and different GS groups of PCa were compared and analyzed respectively. The diagnostic accuracy of each parameter was evaluated by using the receiver operating characteristic (ROC) curve. The correlation between each parameter and GS was analyzed by using Spearman's rank correlation. RESULTS: The MK and MTRasym (3.5 ppm) values were significantly higher in PCa group than in BPH group, while the MD value was significantly lower than in BPH group. The differences of MK/MD/MTRasym (3.5 ppm) between any two of the low-risk, intermediate-risk, and high-risk groups were all statistically significant (p <0.05). The MK value showed the highest diagnostic accuracy in differentiating PCa and BPH, BPH and low-risk, low-risk and intermediate-risk, intermediate-risk and high-risk (AUC = 0.965, 0.882, 0.839, 0.836). The MK/MD/MTRasym (3.ppm) values showed good and moderate correlation with GS (r = 0.844, -0.811, 0.640, p <0.05), respectively. CONCLUSION: DKI and APT imaging are valuable in the diagnosis of PCa and demonstrate strong correlation with GS, which has great significance in the risk assessment of PCa.

Fabrication of PCL/keratin composite scaffolds for vascular tissue engineering with catalytic generation of nitric oxide potential.

Tissue-engineered vascular grafts (TEVGs) have been proposed as a promising approach to fulfill the need for small-diameter blood vessel substitutes. However, common failure caused by thrombosis and neointimal proliferation after implantation has restricted their use in the clinic. Herein, a NO-generating scaffold for vascular tissue engineering was developed by coelectrospinning poly(ε-caprolactone) (PCL) with keratin. The morphology and surface chemical composition were characterized via SEM, ATR-FTIR spectroscopy and XPS. The biocomposite scaffold selectively enhanced the adhesion and growth of endothelial cells (ECs) while suppressing the proliferation of smooth muscle cells (SMCs) in the presence of GSH and GSNO due to the catalytic generation of NO. In addition, these mats displayed excellent blood compatibility by prolonging the blood-clotting time. In summary, these NO-generating PCL/keratin scaffolds have potential applications in vascular tissue engineering with rapid endothelialization and reduced SMC proliferation.

The Value of Low-dose Prospective Dual-energy Computed Tomography with Iodine Mapping in the Diagnosis of Gastric Cancer.

OBJECTIVES: This study investigated the radiation dose and value of prospective dualenergy computed tomography (DECT) in the diagnosis of gastric cancer. METHODS: Sixty patients scheduled for computed tomography (CT) for preoperative staging were divided into two groups. Thirty patients (Group A) underwent a single contrast-enhanced abdominal CT acquisition using a dual-source mode (100 kV/140 kV). Weighted average images of the two-kilovolt acquisitions and iodine maps were created. The remaining 30 patients underwent a standard CT scan (Group B). Two observers performed a blinded read of the images for gastric lesions, evaluating the image quality and recording effective dose. RESULTS: During the blinded read, observers found 90% (27/30) of the cancers in both groups. The mean imaging quality scores were 2.1±0.9 for Group A, and 2.3±1.1 for Group B. The effective mean doses were 6.59±0.59 mSv and 25.86±0.44 mSv for Groups A and B, respectively. Compared with the control group (B), the imaging quality in the low-dose group decreased a little, but the radiation dose substantially decreased by 74.6%. CONCLUSION: The new DECT technique is valuable for examining gastric cancer patients. The dualkV scan mode can substantially reduce radiation dose while preserving good diagnostic image quality.

Catalytic Generation of Nitric Oxide from Poly(ε-caprolactone)/Phosphobetainized Keratin Mats for a Vascular Tissue Engineering Scaffold.

Tissue-engineered vascular graft (TEVG) is a promising alternative to meet the clinical demand of organ shortages. Herein, human hair keratin was extracted by the reduction method, followed by modification with zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) through thiol-Michael addition to improve blood clotting nature. Then, phosphobetainized keratin (PK) was coelectrospun with poly(ε-caprolactone) (PCL) to afford PCL/PK mats with a ratio of 7:3. The surface morphology, chemical structure, and wettability of these mats were characterized. The biocomposite mats selectively enhanced adhesion, migration, and growth of endothelial cells (ECs) while suppressed proliferation of smooth muscle cells (SMCs) in the presence of glutathione (GSH) and GSNO due to the catalytic generation of NO. In addition, these mats exhibited good blood anticoagulant activity by reducing platelet adhesion, prolonging blood clotting time, and inhibiting hemolysis. Taken together, these NO-generating PCL/PK mats have potential applications as a scaffold for vascular tissue engineering with rapid endothelialization and reduced SMC proliferation.

Poly(ε-caprolactone)/keratin/heparin/VEGF biocomposite mats for vascular tissue engineering.

Vascular endothelial growth factor (VEGF) is an effective growth and angiogenic cytokine, which stimulates proliferation and survival of endothelial cells, and promotes angiogenesis and vascular permeability. Binding VEGF with heparin could protect it from rapid degradation, subsequently allowing it to be controlled release. Primarily, poly(ε-caprolactone) (PCL) and keratin were coelectrospun, followed by conjugating with heparin and subsequently binding VEGF. The loaded heparin and VEGF on these mats were quantified, respectively. The surface characteristics of mats were investigated by scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). The VEGF delivery results indicated these mats could sustainably release VEGF for 2 weeks. Cell viability assays suggested these mats were valid to accelerate human umbilical vein endothelial cells (HUVECs) proliferation, while inhibit human umbilical arterial smooth muscle cells (HUASMCs) growth under the combined actions of VEGF and heparin. The results tested by blood clotting times (APTT, PT, and TT), hemolysis, and platelet adhesion indicated the mats were blood compatible. To sum up, these biocomposite mats are ideal scaffolds for vascular tissue engineering.

PCL/sulfonated keratin mats for vascular tissue engineering scaffold with potential of catalytic nitric oxide generation.

Heparin-like polymers have a good anticoagulant effect due to some groups similar to heparin. Herein, sulfonated keratin(SK) was prepared by chain transfer radical polymerization of 3-sulfopropyl methacrylate(SPMA) to improve blood coagulation nature of keratin. Poly(ε-caprolactone)(PCL)/SK nanofibrous mats with the ratio of 7 and 3 were then fabricated by electrospinning. In vitro cytotoxicity and blood compatibility tests were performed to assess the biocompatibility. Viability of NIH 3T3 cells on PCL/SK mats was higher than that on the pristine PCL mats, indicating their good cytocompatibility. These sulfonated keratin-containing mats enhanced endothelial cell growth, while inhibited smooth muscle cell proliferation and reduced platelet adhesion in the presence of GSH and GSNO, as a result of NO generation. Furthermore, the biocomposite mats prolonged the activated partial thromboplastin time(APTT) effectively without hemolysis. Taken together, PCL/SK mats are potential for applications in vascular tissue engineering.

Use of a modified endotracheal tube for self-expandable metallic Y-shaped airway stent deployment without rigid bronchoscope or fluoroscopic guidance.

BACKGROUND: Self-expandable metallic Y-shaped airway stents (SEMYS) are commonly used in the management of airway stenosis and fistulae caused by thoracic neoplasms. METHODS: A new technique using a slightly modified regular endotracheal tube has been developed for the deployment of SEMYS with flexible bronchoscopy alone. The technique and devices are described. RESULTS: To date, successful deployment of SEMYS with this method has been carried out successfully in 17 out of 20 patients without major complications while the other 3 required conversion to rigid bronchoscopy because of limited pharyngeal cavity space, massive hemorrhage and severe cicatrization of the airway, respectively. CONCLUSIONS: This simplified deployment technique with the modified endotracheal tube enables safe, simple and fast insertion of SEMYS in a regular bronchoscopy suite, which may benefit the vast less privileged institutions where SEMYS are necessary but rigid bronchoscopy and fluoroscopy are not available. The skill of the bronchoscopist, cautious selection of patients and effective coordination of the operating team are crucial for the procedure.

Neurobiological Mechanisms of Metacognitive Therapy - An Experimental Paradigm.

INTRODUCTION: The neurobiological mechanisms underlying the clinical effects of psychotherapy are scarcely understood. In particular, the modifying effects of psychotherapy on neuronal activity are largely unknown. We here present data from an innovative experimental paradigm using the example of a patient with treatment resistant obsessive-compulsive disorder (trOCD) who underwent implantation of bilateral electrodes for deep brain stimulation (DBS). The aim of the paradigm was to examine the short term effect of metacognitive therapy (MCT) on neuronal local field potentials (LFP) before and after 5 MCT sessions. METHODS: DBS electrodes were implanted bilaterally with stereotactic guidance in the bed nucleus of the stria terminalis/ internal capsule (BNST/IC). The period between implantation of the electrodes and the pacemaker was used for the experimental paradigm. DBS electrodes were externalized via extension cables, yielding the opportunity to record LFP directly from the BNST/IC. The experimental paradigm was designed as follows: (a) baseline recording of LFP from the BNST/IC, (b) application of 5 MCT sessions over 3 days, (c) post-MCT recording from the BNST/IC. The Obsessive-Compulsive Disorder- scale (OCD-S) was used to evaluate OCD symptoms. RESULTS: OCD symptoms decreased after MCT. These reductions were accompanied by a decrease of the relative power of theta band activity, while alpha, beta, and gamma band activity was significantly increased after MCT. Further, analysis of BNST/IC LFP and frontal cortex EEG coherence showed that MCT decreased theta frequency band synchronization. DISCUSSION: Implantation of DBS electrodes for treating psychiatric disorders offers the opportunity to gather data from neuronal circuits, and to compare effects of therapeutic interventions. Here, we demonstrate direct effects of MCT on neuronal oscillatory behavior, which may give possible cues for the neurobiological changes associated with psychotherapy.

Primary Tracheal Mucosa-Associated Lymphoid Tissue Lymphoma Treated with a Water-Jet Hybrid Knife: A Case Report.

Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the trachea is very rare and is easily misdiagnosed as a bronchogenic carcinoma or benign tracheal tumor. Here, we report a clinical case where a new clinical approach involving a water-jet hybrid knife was employed in the diagnosis and treatment of primary tracheal MALT lymphoma.

Electrospun PCL/keratin/AuNPs mats with the catalytic generation of nitric oxide for potential of vascular tissue engineering.

Nitric oxide (NO)-generating materials are beneficial for vascular tissue engineering (VTE) scaffold because the produced NO would enhance endothelial cells viability while inhibit smooth muscle cell (SMC) proliferation and reduce platelet adhesion, resulting in ideal hemocompatibility and endothelialization. Herein, poly(ε-caprolactone) (PCL)/keratin biocomposite mats were first fabricated, followed by in situ gold (Au) nanoparticles loading to afford PCL/keratin/AuNPs mats. These mats were characterized using field emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The PCL/keratin/AuNPs mats were demonstrated to be capable of catalyzing NO release in the mimicked blood microenvironments. The generated NO could enhance human umbilical vein endothelial cell growth and inhibit human umbilical arterial SMC viability. In addition, these mats maintained the antibacterial activity of Au nanoparticles with good blood compatibility. Taken together, these keratin-based composite mats have potential usage in the VTE. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 3239-3247, 2018.

Heparinized PCL/keratin mats for vascular tissue engineering scaffold with potential of catalytic nitric oxide generation.

Heparins are capable of improving blood compatibility, enhancing HUVEC viability, while inhibiting HUASMC proliferation. Combination of biodegradable poly(ε-caprolactone) (PCL) with keratin and heparins would provide an anticoagulant and endothelialization supporting environment for vascular tissue engineering. Herein, PCL and keratin were first coelectrospun and then covalently conjugated with heparins. The resulting mats were surface-characterized by ATR-FTIR, SEM, WCA, and XPS. Cell viability data showed that the heparinized PCL/keratin mats could motivate the adhesion and growth of HUVEC, while inhibit HUASMC proliferation. In addition, these mats could prolong blood clotting time and reduce platelet adhesion as well as no erythrolysis. Interestingly, these mats could catalyze the NO donor in blood to release NO, which could enhance endothelial cell growth, while decrease smooth muscle cell proliferation and platelet adhesion. In summary, the heparinized mats would be a good candidate as a scaffold for vascular tissue engineering. This study is novel in that we prepared a type of heparinized tissue scaffold that could catalyze the NO donor to release NO to regulate endothelialization without angiogenesis and thrombus formation.

Comparative Analysis of microRNA Expression Profiles of Exosomes Derived from Normal and Hypoxic Preconditioning Human Neural Stem Cells by Next Generation Sequencing.

Stroke recovery is associated with neural stem cell (NSC) development and neurovascular unit reconstruction. The exosome, as an important intercellular player in neurovascular communication, mediates neuro-restorative events by transferring exosomal protein and RNA cargoes. In this study, we explored the role of exosomal microRNAs (miRNAs) in human NSCs (hNSCs), and analyzed the expression profiles of miRNAs in hNSC-derived and hypoxic preconditioning hNSC-derived exosomes with the help of next generation sequencing (NGS). The results demonstrated that a certain proportion of miRNAs were differentially expressed in both exosomes. In addition, target gene prediction and Gene Ontology (GO) enrichment analysis showed that these genes were associated with differential miRNAs primarily participating in biological processes (regulation of cellular process), cellular component (intracellular membrane-bounded organelle), and molecular function (binding). Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) pathway enrichment data suggested that most of targeted genes involved in PI3K-Akt, Hippo, MAPK, mTOR, and Endocytosis etc. signaling pathways. We identified the interesting and important expressed miRNA and considered that miR-98-3p might be a special hNSC-derived exosomal-miRNA which was significantly downregulated under hypoxic preconditioning. The hNSCs-derived exosomes were capable of modulating gene expression or promoting stroke therapy. We observed that after hypoxic preconditioning, the functions of these exosomes were changed, and exosomal-miRNAs expression profile was different. In summary, our study suggested that hNSC-derived exosomal miRNAs including hypoxic preconditioning exosomal miRNAs provided a new strategy for the diagnosis and treatment of stroke patients.

Neural Stem Cells Alleviate Inflammation via Neutralization of IFN-γ Negative Effect in Ischemic Stroke Model.

Inflammatory response generated by ischemic stroke commonly affects functional or structural recovery. The aim of this study was to examine the IFN-γ caused inflammatory effects on NSCs in vitro and in vivo. We found that IFN-γ did not affect NSCs proliferation but increased the SOD2 level of inflammatory oxidative stress in NSCs culturing. High dose IFN-γ (500 ng) injection aggravated the level of inflammation in the cerebral ischemic model but did not alter the repairing functions of the NSCs in vivo. NSCs based treatment, including the NSCs-IFN-γ combined treatment, significantly improved the ischemic microenvironment by decreasing CD4+, CD8+ T cells and microglia infiltration. Furthermore, anti-inflammatory cytokines IL-10 and TGF-ß1 expression were increased in the NSCs and combined treatment groups, but the level of pro-inflammatory cytokines (IL-1 ß, IL-6, IFN-γ, and TNF-α) were decreased. The IFN-γ/Stat1 signaling pathway was also activated. NSCs transplantation therefore promoted the neurological recovery of ischemic stroke rats mainly by altering the inflammatory microenvironment, neutralizing the negative effect of IFN-γ. In conclusion, in addition to promoting cell replacement or engraftment, the NSCs-based transplantation also enhanced the therapeutic effects of transplantation by optimizing its immune microenvironment of ischemic areas.

Neuronal firing activity in the basal ganglia after striatal transplantation of dopamine neurons in hemiparkinsonian rats.

The loss of nigral dopaminergic neurons and the resulting dopamine (DA) depletion in the striatum (STR) lead to altered neuronal activity and enhanced beta activity in various regions of the basal ganglia (BG) motor loop in patients with Parkinson's disease and in rodents in the 6-hydroxydopamine (6-OHDA)-lesioned rat model. Intrastriatal DA graft implantation has been shown to re-innervate the host brain and restore DA input. Here, DA cell grafts were implanted into the STR of 6-OHDA-lesioned rats and the effect on neuronal activity under urethane anesthesia (1.4g/kg, injected intraperitoneally) was tested in the entopeduncular nucleus (EPN, the equivalent to the human globus pallidus internus), the output nucleus of the BG, and the globus pallidus (GP, the equivalent to the human globus pallidus externus), a key region in the indirect pathway. In animals, which were transplanted with cells derived from the ventral mesencephalon of embryonic day 12 rat embryos into the STR, the rotational behavior induced by DA agonists in 6-OHDA-lesioned rats was significantly improved. This was accompanied by alleviated EPN firing rate and reinstated patterns of neuronal activity in the GP and EPN. Analysis of oscillatory activity revealed enhanced beta activity in both regions, which was reduced after grafting. In summary these data indicate restoration of BG motor loop toward normal activity by DA graft integration.