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1.
J Cosmet Dermatol ; 2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39136194

RESUMO

BACKGROUND: Rosacea can be seen in many patients nowadays, and the related causes are complex. Despite a certain association between smoking and rosacea being reported by several studies, the actual causality has not been established for the possible bias and confounders. METHODS: We used Mendelian randomization (MR) to evaluate a potential causal effect of smoking on rosacea risk. Statistics on smoking and rosacea were obtained from the FinnGen project and Neale Lab Consortium. The causal association was assessed by multiple methods including inverse variance weighted (IVW), MR Egger, weighted median, and weighted mode. Furthermore, sensitivity analyses were also conducted to address pleiotropy, along with the leave-one-out method.R version 4.2.3 was applied for the analyses. RESULTS: The IVW estimation revealed that previous smoking has a deleterious effect on rosacea (odds ratio [OR] = 6.7729, 95% confidence interval [CI] = 1.5691-29.2356, p = 0.0104). By contrast, there was no statistically relationship between current smokers and rosacea (OR = 0.6180, 95% CI = 0.0605-6.3094, p = 0.6847). Results were similar in the analysis based on the weighted median method (previous smoking: OR = 8.6297, 95% CI = 1.0131-73.5071, p = 0.0486; current smoking: OR = 0.2896, 95% CI = 0.0106-7.9132, p = 0.4627). The stability of the causal effect estimates was supported by several sensitivity analyses and the leave-one-out method. CONCLUSION: Our MR study found support forrosacea risk and previous smoking. Although no evidence was found to increase the risk of rosacea in current smokers, to prevent various diseases associated with smoking, the public should be encouraged to avoid smoking at the very beginning.

2.
Appl Microbiol Biotechnol ; 107(23): 7135-7150, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37768347

RESUMO

Interleukin-18 binding protein (IL-18BP) is a natural IL-18 inhibitor in vivo, which can effectively neutralize IL-18 and inhibit the inflammatory signaling pathway induced by IL-18, thus playing an anti-inflammatory role. Traditional production methods primarily rely on eukaryotic animal cell expression systems, which often entail complex processes, lower yields, and increase production costs. In this study, we present a novel approach for expressing IL-18BP fusion protein using the Escherichia coli (E. coli) system. The N-terminal segment of IL-18BP was fused with the small ubiquitin-related modifier (SUMO) tag, enabling soluble expression, while the C-terminal segment was fused with the human IgG1 Fc fragment to prolong its in vivo lifespan. Through screening, we obtained a high-expression engineering strain from a single colony and developed optimized protocols for fermentation and purification of the recombinant SUMO-IL-18BP-Fc protein. The SUMO tag was subsequently cleaved using SUMO protease, and the purified recombinant human IL-18BP-Fc (rhIL-18BP-Fc) exhibited a purity exceeding 90% with a yield of 1 g per liter of bacterial solution. The biological activities and underlying mechanisms of rhIL-18BP-Fc were evaluated using cell lines and a mouse model. Our results demonstrated that rhIL-18BP-Fc effectively inhibited IL-18-stimulated IFN-γ production in KG-1a cells in vitro and ameliorated DSS-induced ulcerative colitis in mice. In conclusion, we successfully employed the SUMO fusion system to achieve high-level production, soluble expression, and prolonged activity of rhIL-18BP-Fc in E. coli. These findings lay the groundwork for future large-scale industrial production and pharmaceutical development of rhIL-18BP-Fc protein. KEY POINTS: • Effective expression, fermentation, and purification of bioactive rhIL-18BP-Fc protein in E. coli. • The rhIL-18BP-Fc protein has a great potential for the therapy of ulcerative colitis by inhibiting the expression of inflammatory factors.


Assuntos
Colite Ulcerativa , Interleucina-18 , Humanos , Camundongos , Animais , Interleucina-18/genética , Interleucina-18/metabolismo , Colite Ulcerativa/tratamento farmacológico , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes de Fusão/metabolismo
3.
Small ; 19(50): e2304610, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37632302

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease commonly associated with the accumulation of hyperactive immune cells (HICs), particularly macrophages of pro-inflammatory (M1) phenotype, accompanied by the elevated level of reactive oxygen species (ROS), decreased pH and O2 content in joint synovium. In this work, an immunomodulatory nanosystem (IMN) is developed for RA therapy by modulating and restoring the function of HICs in inflamed tissues. Manganese tetraoxide nanoparticles (Mn3 O4 ) nanoparticles anchored on UiO-66-NH2 are designed, and then the hybrid is coated with Mn-EGCG film, further wrapped with HA to obtain the final nanocomposite of UiO-66-NH2 @Mn3 O4 /Mn-EGCG@HA (termed as UMnEH). When UMnEH diffuses to the inflammatory site of RA synovium, the stimulation of microwave (MW) irradiation and low pH trigger the slow dissociation of Mn-EGCG film. Then the endogenously overexpressed hydrogen peroxide (H2 O2 ) disintegrates the exposed Mn3 O4 NPs to promote ROS scavenging and O2 generation. Assisted by MW irradiation, the elevated O2 content in the RA microenvironment down-regulates the expression of hypoxia-inducible factor-1α (HIF-1α). Coupled with the clearance of ROS, it promotes the re-polarization of M1 phenotype macrophages into anti-inflammatory (M2) phenotype macrophages. Therefore, the multifunctional UMnEH nanoplatform, as the IMN, exhibits a promising potential to modulate and restore the function of HICs and has an exciting prospect in the treatment of RA.


Assuntos
Artrite Reumatoide , Nanocompostos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Manganês , Catalase , Micro-Ondas , Artrite Reumatoide/tratamento farmacológico , Oxigênio/metabolismo
5.
Cells ; 12(10)2023 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-37408250

RESUMO

Extracellular vesicles (EVs) such as ectosomes and exosomes have gained attention as promising natural carriers for drug delivery. Exosomes, which range from 30 to 100 nm in diameter, possess a lipid bilayer and are secreted by various cells. Due to their high biocompatibility, stability, and low immunogenicity, exosomes are favored as cargo carriers. The lipid bilayer membrane of exosomes also offers protection against cargo degradation, making them a desirable candidate for drug delivery. However, loading cargo into exosomes remains to be a challenge. Despite various strategies such as incubation, electroporation, sonication, extrusion, freeze-thaw cycling, and transfection that have been developed to facilitate cargo loading, inadequate efficiency still persists. This review offers an overview of current cargo delivery strategies using exosomes and summarizes recent approaches for loading small-molecule, nucleic acid, and protein drugs into exosomes. With insights from these studies, we provide ideas for more efficient and effective delivery of drug molecules by using exosomes.


Assuntos
Micropartículas Derivadas de Células , Exossomos , Vesículas Extracelulares , Exossomos/metabolismo , Bicamadas Lipídicas/metabolismo , Sistemas de Liberação de Medicamentos , Vesículas Extracelulares/metabolismo
6.
Heliyon ; 9(6): e16867, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37313148

RESUMO

Considering the rarity and aggressive nature of retroperitoneal leiomyosarcoma (RLMS), several prognostic factors might contribute to the cancer-specific mortality of these patients. This study aimed to construct a competing risk-based nomogram to predict cancer-specific survival (CSS) for patients with RLMS. In total, 788 cases from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2015) were included. Based on the Fine & Gray's method, independent predictors were screened to develop a nomogram for predicting 1-, 3-, and 5-year CSS. After multivariate analysis, CSS was found significantly associated with tumor characteristics (tumor grade, size, range), as well as surgery status. The nomogram showed solid prediction power and was well calibrated. Through decision curve analysis (DCA), a favorable clinical utility of the nomogram was demonstrated. Additionally, a risk stratification system was developed and distinctive survival between risk groups was observed. In summary, this nomogram showed a better performance than the AJCC 8th staging system and can assist in the clinical management of RLMS.

7.
Artigo em Inglês | MEDLINE | ID: mdl-35722137

RESUMO

Hypertrophic scarring (HS), caused by excessive fibrosis of injured skin, imposes a psychological burden and creates a source of distress that impairs the quality of life of affected individuals. However, the gold standard for HS treatment has not yet been determined due to the complicated and difficult nature of the routines and procedures involved. Previous studies have indicated that the topical application of certain active components found in traditional Chinese medicines shows potential as a therapeutic alternative for scars. Here, single-cell RNA-sequencing was performed to determine cellular heterogeneity and identify marker genes and mechanisms associated with HS. It was found that fibroblasts comprise the largest proportion of HS cell types. The marker genes that were highly expressed in fibroblasts were extracellular matrix (ECM)-related, whereas ECM-receptor interactions and the transforming growth factor (TGF)-ß signalling pathway were also found to be active. Ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry, which was applied to identify the molecular compounds of Dispel-Scar Ointment (DSO), revealed 74 effective chemical components belonging to 14 types of constituents, such as flavonoids, tanshinones, salvianolic acids, glycosides, and phthalides. Furthermore, in vivo studies using rat scar models showed that the topical application of Salvia miltiorrhiza, Ligusticum chuanxiong, peach kernel, safflower, and motherwort exerted beneficial effects on fibroblasts. DSO promoted scar maturation and reduced scar areas, its efficacy being similar to that of topically applied silicone. Functional studies using immunofluorescence staining, western blotting, and quantitative real-time polymerase chain reaction demonstrated that DSO may target the TGF-ß/Smad pathway to inhibit collagen synthesis and promote ECM remodelling. However, further in vitro mechanistic research and single-drug prescription studies may be required to identify the specific effective compound or active ingredient of DSO, which would provide more substantial evidence regarding the potential therapeutic value of traditional herbs in HS.

9.
Genet Test Mol Biomarkers ; 25(7): 504-514, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34280005

RESUMO

Objective: This study was designed to analyze the expression of CSNK1D in hepatocellular carcinoma (HCC) and investigate the relationship between the expression of CSNK1D and the prognosis of HCC patients. Methods: The CSNK1D and alpha-fetoprotein (AFP) expression levels in patients with HCC and their corresponding clinical data were downloaded from The Cancer Genome Atlas (TCGA) and sorted with a Perl program. CSNK1D and AFP expression differences in liver tissue and liver cancer were compared and analyzed, based on the online database human cancer metastasis database, the relationships between the expression levels of CSNK1D and AFP and the proliferation and metastases of HCC were explored. The immunohistochemical data obtained from the Human Protein Atlas Database further verified the differences in the expression levels of CSNK1D and AFP in liver tissues and liver cancer tissues. Through Kaplan-Meier survival analysis, the effects of CSNK1D and AFP expression levels on the prognosis of patients with HCC were investigated, and the influences of and patients' gender, age and grades of cancer cells, tumor size, the status of lymph node metastasis, distant metastasis, and tumor stage on the expression of CSNK1D were analyzed with R language. The influence of differential expressions of CSNK1D on survival time was compared and the prognostic factors influencing the survival of HCC patients were statistically explored by univariate analysis and multivariate analysis. The potential influencing mechanism of CSNK1D on the prognosis of HCC patients was explored by Gene Set Enrichment Analysis (GSEA) enrichment. Results: The expression level of CSNK1D and AFP in cancer foci was significantly higher than that in normal tissues, However, in the same patient, the expression levels of AFP in paracarcinoma tissues and cancer tissues showed no significant difference. The expression level of CSNK1D in HCC with distant metastases was higher than that in those without metastasis, but the expression level of AFP in metastatic HCC was lower than that in those HCC without metastases. In immunohistochemical tests, CSNK1D was moderately positive in normal liver tissues, slightly positive in normal bile duct tissues, and highly positive in HCC. AFP was slightly positive in normal liver tissues and negative in HCC, but it was not detected in normal intrahepatic bile duct tissue. Survival analysis results suggested that the higher expression level of CSNK1D corresponded to the shorter survival period, whereas the expression level of AFP showed no significant influence on survival time. The expression level of CSNK1D was not correlated with gender, age, the status of lymph node metastasis status, or distant metastasis of patients. The main factors influencing the expression level of CSNK1D included tumor size, cancer cell grade, and tumor stage. The expression levels of CSNK1D in T2 and T3 were higher than that in T1. The expression levels of CSNK1D in G3 and G4 were higher than that in G1. The expression levels of CSNK1D in Stage II and Stage III were higher than that in Stage I. Univariate analysis suggested that tumor size, cell grade, distant metastasis, clinical stage, and CSNK1D expression level were the prognostic factors influencing the survival of patients. Multivariate analysis suggested that CSNK1D expression level was an independent factor influencing the prognosis of HCC patients. GSEA enrichment analysis indicated that CSNK1D mainly affected the prognosis of HCC patients through cell cycle, WNT signaling pathway, amino acid degradation metabolism, and other pathways. Conclusion: CSNK1D is an independent influencing factor for the prognosis of HCC patients and has the potential to be developed as a potential therapeutic target for HCC, and better than AFP in predicting the prognosis of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Caseína Quinase Idelta/genética , Adulto , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/patologia , Caseína Quinase I/genética , Caseína Quinase I/metabolismo , Caseína Quinase Idelta/metabolismo , Bases de Dados Genéticas , Feminino , Expressão Gênica/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Estimativa de Kaplan-Meier , Fígado/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Transcriptoma/genética , alfa-Fetoproteínas/genética , alfa-Fetoproteínas/metabolismo
10.
Magn Reson Med ; 80(4): 1568-1576, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29405374

RESUMO

PURPOSE: To develop a method that can separate and quantify the fast (>1 kHz) and slow exchange transfer and magnetization transfer components in Z-spectra. METHODS: Z-spectra were recorded as a function of mixing time using a train of selective pulses providing variable-delay multipulse build-up curves. Fast and slow transfer components in the Z-spectra were separated and quantified on a voxel-by-voxel basis by fitting the mixing time-dependent CEST signal using a 3-pool model. RESULTS: Phantom studies of glutamate solution, bovine serum albumin solution, and hair conditioner showed the capability of the proposed method to separate fast and slow transfer components. In vivo mouse brain studies showed a strong contrast between white matter and gray matter in the slow-transferring map, corresponding to an asymmetric component of the conventional semisolid magnetization transfer contrast. In addition, a fast-transferring proton map was found that was homogeneous across the brain and attributed to the total contributions of the fast-exchanging protons from proteins, metabolites, and a symmetric magnetization transfer contrast component. CONCLUSIONS: This new method provides a simple way to extract fast and slow transfer components from the Z-spectrum, leading to novel MRI contrasts, and providing insight into the different magnetization transfer contrast contributions.


Assuntos
Encéfalo , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Feminino , Glutamina/metabolismo , Camundongos , Camundongos SCID , Imagens de Fantasmas
11.
Oncol Res ; 26(3): 335-343, 2018 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-28390115

RESUMO

Long noncoding RNAs (lncRNAs) have been verified to participate in various types of malignant tumors, including osteosarcoma (OS), which is the most common primary bone tumor with outstanding morbidity. Although an increasing number of lncRNAs have been reported to mediate the occurrence of OS, the potential mechanisms are still unclear. This study intends to uncover the mechanism by which lncRNA LINC01133 functions as an miRNA sponge to mediate OS tumorigenicity. In this study, we found that the expression level of LINC01133 was statistically upregulated in OS tumor tissue and cell lines compared to noncancerous tissues and a normal human osteoplastic cell line. LINC01133 silencing could also observably suppress the proliferation, migration, and invasion of OS cells (HOS and U2-OS). Bioinformatics analysis predicted that LINC01133 specifically targeted miR-422a, which was validated by dual-luciferase reporter assay. Furthermore, functional experiments revealed that miR-422a played a tumor-suppressive role in OS progression and could effectively reverse the function of LINC01133. In summary, our study discovered that lncRNA LINC01133 aggravates the proliferation, migration, and invasion of OS by sponging miR-422a, which provides a novel insight in the tumorigenesis of OS.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Ósseas/patologia , Proliferação de Células , MicroRNAs/genética , Osteossarcoma/patologia , RNA Longo não Codificante/genética , Apoptose , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Carcinogênese , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Humanos , Osteossarcoma/genética , Osteossarcoma/metabolismo , Prognóstico , Taxa de Sobrevida , Células Tumorais Cultivadas
12.
NMR Biomed ; 30(12)2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28961344

RESUMO

The current study aims to assign and estimate the total creatine (tCr) signal contribution to the Z-spectrum in mouse brain at 11.7 T. Creatine (Cr), phosphocreatine (PCr) and protein phantoms were used to confirm the presence of a guanidinium resonance at this field strength. Wild-type (WT) and knockout mice with guanidinoacetate N-methyltransferase deficiency (GAMT-/-), which have low Cr and PCr concentrations in the brain, were used to assign the tCr contribution to the Z-spectrum. To estimate the total guanidinium concentrations, two pools for the Z-spectrum around 2 ppm were assumed: (i) a Lorentzian function representing the guanidinium chemical exchange saturation transfer (CEST) at 1.95 ppm in the 11.7-T Z-spectrum; and (ii) a background signal that can be fitted by a polynomial function. Comparison between the WT and GAMT-/- mice provided strong evidence for three types of contribution to the peak in the Z-spectrum at 1.95 ppm, namely proteins, Cr and PCr, the latter fitted as tCr. A ratio of 20 ± 7% (protein) and 80 ± 7% tCr was found in brain at 2 µT and 2 s saturation. Based on phantom experiments, the tCr peak was estimated to consist of about 83 ± 5% Cr and 17 ± 5% PCr. Maps for tCr of mouse brain were generated based on the peak at 1.95 ppm after concentration calibration with in vivo magnetic resonance spectroscopy.


Assuntos
Encéfalo/metabolismo , Creatina/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Fosfocreatina/metabolismo
13.
J Craniofac Surg ; 28(6): 1578-1581, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28749836

RESUMO

INTRODUCTION: Cosmetic injections of dermal fillers or fat could cause ophthalmic artery embolism and even blindness, the high-risk regions of which are considered glabellar, nasal dorsum, and nasolabial fold. Understanding anatomy of the related arteries is important for a physician to safely perform filler injections. To investigate the mechanisms of ophthalmic artery embolism following the injections, cadaver anatomy was studied. METHODS: Ophthalmic artery, facial artery, their branches, and anastomoses among them were anatomized in 12 fresh cadavers. Mimetic injections of hyaluronic acid were performed in glabellar region, nasal dorsum, and nasolabial fold, the relationships between injected filler and related arteries were then investigated. RESULTS: It was clearly found that 4 arteries were located in common injection regions and connected to ophthalmic artery: supratrochlear artery, supraorbital artery, dorsal nasal artery, and angular artery. In the glabellar region, the deep injection on the periosteum will be risky to injure supratrochlear artery and supraorbital artery, whereas in nasal dorsum and nasolabial fold, the sub- superficial musculo aponeurotic system layer injection has the possibility to injure dorsal nasal artery, angular artery, and facial artery. CONCLUSION: The anatomic mechanism of ophthalmic artery embolism is the anastomoses among the related arteries and ophthalmic artery. Based on the findings of the study, injections in periosteum layer at glabellar region or sub-superficial musculo aponeurotic system layer of nasal dorsum and nasolabial fold are not advised.


Assuntos
Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/efeitos adversos , Embolia , Artéria Oftálmica/anatomia & histologia , Embolia/etiologia , Embolia/patologia , Humanos , Modelos Biológicos
14.
Molecules ; 22(5)2017 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-28481233

RESUMO

Europium (Eu)-doped fluorapatite (FA) nanorods have a biocompatibility similar to that of hydroxyapatite (HA) for use as cell imaging biomaterials due to their luminescent property. Here, we discuss the new application of europium-doped fluorapatite (Eu-FA) nanorods as an anticancer drug carrier. The Eu-FA nanorods were prepared by using a hydrothermal method. The morphology, crystal structure, fluorescence, and composition were investigated. The specific crystal structure enables the effective loading of drug molecules. Doxorubicin (DOX), which was used as a model anticancer drug, effectively loaded onto the surface of the nanorods. The DOX release was pH-dependent and occurred more rapidly at pH 5.5 than at pH 7.4. The intracellular penetration of the DOX-loaded Eu-FA nanorods (Eu-FA/DOX) can be imaged in situ due to the self-fluorescence property. Treatment of melanoma A375 cells with Eu-FA/DOX elicited a more effective apoptosis rate than direct DOX treatment. Overall, Eu-FA exhibits potential for tracking and treating tumors and may be potentially useful as a multifunctional carrier system to effectively load and sustainably deliver drugs.


Assuntos
Apatitas/química , Doxorrubicina/farmacocinética , Portadores de Fármacos/química , Európio/química , Nanotubos/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Liberação Controlada de Fármacos , Humanos , Cinética , Luminescência , Imagem Óptica/métodos , Tamanho da Partícula , Porosidade , Propriedades de Superfície
15.
J Am Chem Soc ; 138(35): 11136-9, 2016 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-27548755

RESUMO

A two-step heteronuclear enhancement approach was combined with chemical exchange saturation transfer (CEST) to magnify (15)N MRI signal of molecules through indirect detection via water protons. Previous CEST studies have been limited to radiofrequency (rf) saturation transfer or excitation transfer employing protons. Here, the signal of (15)N is detected indirectly through the water signal by first inverting selectively protons that are scalar-coupled to (15)N in the urea molecule, followed by chemical exchange of the amide proton to bulk water. In addition to providing a small sensitivity enhancement, this approach can be used to monitor the exchange rates and thus the pH sensitivity of the participating (15)N-bound protons.


Assuntos
Imageamento por Ressonância Magnética/métodos , Isótopos de Nitrogênio/química , Prótons , Água/química
16.
Magn Reson Med ; 75(1): 88-96, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26445350

RESUMO

PURPOSE: To use the variable delay multipulse (VDMP) chemical exchange saturation transfer (CEST) approach to obtain clean amide proton transfer (APT) and relayed Nuclear Overhauser enhancement (rNOE) CEST images in the human brain by suppressing the conventional magnetization transfer contrast (MTC) and reducing the direct water saturation contribution. METHODS: The VDMP CEST scheme consists of a train of RF pulses with a specific mixing time. The CEST signal with respect to the mixing time shows distinguishable characteristics for protons with different exchange rates. Exchange rate filtered CEST images are generated by subtracting images acquired at two mixing times at which the MTC signals are equal, while the APT and rNOE-CEST signals differ. Because the subtraction is performed at the same frequency offset for each voxel and the CEST signals are broad, no B0 correction is needed. RESULTS: MTC-suppressed APT and rNOE-CEST images of human brain were obtained using the VDMP method. The APT-CEST data show hyperintensity in gray matter versus white matter, whereas the rNOE-CEST images show negligible contrast between gray and white matter. CONCLUSION: The VDMP approach provides a simple and rapid way of recording MTC-suppressed APT-CEST and rNOE-CEST images without the need for B0 field correction.


Assuntos
Algoritmos , Amidas/metabolismo , Encéfalo/metabolismo , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética/métodos , Proteínas/metabolismo , Humanos , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
J Magn Reson ; 246: 119-21, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25123540

RESUMO

The development of biocompatible hyperpolarized media is a crucial step towards application of hyperpolarization in vivo. This article describes the achievement of 1% hyperpolarization of 3-amino-1,2,4-triazine protons in water using the parahydrogen induced polarization technique based on signal amplification by reversible exchange (SABRE). Polarization was achieved in less than 1 min.

18.
Plast Reconstr Surg ; 133(2): 142e-153e, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24469185

RESUMO

BACKGROUND: Bone mesenchymal stem cells are progenitor cells for mesenchymal tissues. The objective of this study was to evaluate the subcutaneous ectopic osteogenesis of allogeneic bone mesenchymal stem cells, which were loaded on ß-tricalcium phosphate in canines without immunosuppressive therapy. METHODS: Osteoinduced allogeneic bone mesenchymal stem cells were seeded onto a ß-tricalcium phosphate scaffold to construct tissue-engineered bone. Four dogs (recipients) in the allogeneic group were subcutaneously implanted with the allogeneic bone mesenchymal stem cells/scaffold; four dogs (donors) in the autogeneic group were implanted with the autogeneic bone mesenchymal stem cells/scaffold complex; and four dogs in the control group were implanted with scaffold alone. Systemic immune responses were evaluated by measuring the T-lymphocyte CD4, CD8, and CD4/CD8 subsets of each group. Subcutaneous osteogenesis was compared between the three groups by histologic analysis at week 24 after implantation. RESULTS: Flow cytometry showed no significant differences in the number of CD4 and CD8 T cells and the CD4/CD8 T-cell ratios among the three groups. Histologically, at week 24, both the autogeneic and allogeneic complexes led to subcutaneous osteogenesis, whereas the control group alone did not. There were no significant differences in the percentage of osteogenic area between the allogeneic and the autogeneic complexes on histomorphometric analysis (p > 0.05), which was significantly higher than that produced by the control group alone (p < 0.001). CONCLUSION: The results demonstrate that osteoinduced, allogeneic bone mesenchymal stem cells loaded on ß-tricalcium phosphate enhanced ectopic bone formation in canines without immunosuppressive therapy.


Assuntos
Materiais Biocompatíveis , Fosfatos de Cálcio , Transplante de Células-Tronco Mesenquimais , Osteogênese , Alicerces Teciduais , Animais , Células Cultivadas , Cães , Feminino , Masculino , Transplante Homólogo
19.
J Mater Chem B ; 2(23): 3609-3617, 2014 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-32263797

RESUMO

Terbium (Tb) or europium (Eu)-doped fluorapatite nanorods (Tb/Eu-FHA) were prepared using a hydrothermal method. The structure, morphology, and luminescence of the products were determined using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), and photoluminescence spectra (PL). The surfaces of the Tb/Eu-FHA nanorods were further conjugated with hydrophilic cationic polymers, such as dextran, to enhance hydrophilicity, biocompatibility and cell penetration. Then, the dextran-coated nanorods were cocultured with bone marrow mesenchymal stem cells (BMSCs). A luminescence signal in the cells was detected after 12 hours with a laser scanning confocal microscope (LSCM). Labelled BMSCs were shown to reproducibly exhibit osteogenic differentiation potential in real-time PCR and ELISA assays. In vivo cell-tracking experiments also suggested that dextran-coated Tb-FHA nanorods could be used as a stable tracer of BMSCs. Therefore, dextran-coated Tb-FHA nanorods can be utilised for tracking and monitoring BMSCs in vitro and in vivo. Our current work attempts to provide an excellent fluorescent cell labelling agent for BMSCs in bone tissue engineering.

20.
J Craniofac Surg ; 24(6): 1980-6, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24220386

RESUMO

The purpose of this study was to determine the changes in teeth and hard tissues after preoperative modeling and bimaxillary anterior subapical osteotomy for the treatment of bimaxillary protrusion. Cephalometric analysis was used to evaluate the aesthetic effects and occlusal relationships obtained. The subjects included 19 women and 1 man (aged 19-41 years; average, 29 years) with bimaxillary protrusion who underwent anterior subapical osteotomy of both the maxilla and mandible, with simultaneous genioplasty, if required. Based on a preoperative computer-aided manufacturing/design-assisted and model surgical design and an occlusal guide plate, new occlusal relationships were established for the patients. In addition, the preoperative and postoperative cephalometric radiographs were systematically analyzed. In all patients, the surgical incisions underwent primary healing, with no infection or osteonecrosis. Significant differences were observed in the preoperative and postoperative values of all hard tissue and teeth parameters, except for SGn-FH degrees and Co-MP. The most obvious significant differences were seen in L1-OP°, Id-Pog-Go°, IIA°, U1E-Apog, L1E-Apog, U1E-NA, and L1-NA° (P < 0.001). Postoperative follow-up lasted for 12 to 36 months. All patients eventually achieved normal jaw relationships, tooth arch forms, and Spee curves. No evident irregularities of teeth arrangement or abnormal occlusal relationships were observed. All patients were satisfied with their postoperative facial appearance, except for 1 patient, who underwent repeat surgery because of relapse. With the use of a precise preoperative model surgical design, orthognathic surgery, a simple and time-saving technique, can be used to correct bimaxillary protrusion with satisfactory postoperative occlusal relationship and facial aesthetic appearance and minimal postoperative complications.


Assuntos
Má Oclusão/cirurgia , Mandíbula/cirurgia , Osteotomia Mandibular/métodos , Maxila/cirurgia , Osteotomia Maxilar/métodos , Terapia Assistida por Computador , Adulto , Cefalometria , Desenho de Equipamento/métodos , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Modelos Anatômicos , Planejamento de Assistência ao Paciente , Adulto Jovem
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