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1.
J Am Chem Soc ; 145(47): 25834-25841, 2023 Nov 29.
Artículo en Inglés | MEDLINE | ID: mdl-37967373

RESUMEN

Magnetic nanocatalysts with properties of easy recovery, induced heating, or magnetic levitation play a crucial role in advancing intelligent techniques. Herein, we report a method for the synthesis of versatile core-shell-type magnetic nanocatalysts through "noncontact" hydrogen spillover-driven reduction and migration of iron oxide with the assistance of Pd. In situ analysis techniques were applied to visualize the dynamic evolution of the magnetic nanocatalysts. Pd facilitates the dissociation of hydrogen molecules into activated H*, which then spills and thus drives the iron oxide reduction, gradual outward split, and migration through the carbonaceous shell. By controlling the evolution stage, nanocatalysts having diverse architectures including core-shell, split core-shell, or hollow type, each featuring Pd or PdFe loaded on the carbon shell, can be obtained. As a showcase, a magnetic nanocatalyst (Pd-loaded split core-shell) can hydrogenate crotonaldehyde to butanal (26 624 h-1 in TOF, ∼100% selectivity), outperforming reported Pd-based catalysts. This is due to the synergy of the enhanced local magnetothermal effect and the preferential adsorption of -C═C on Pd with a small d bandwidth. Another catalyst (PdFe-loaded split core-shell) also delivers a robust performance in phenylacetylene semihydrogenation (100% conversion, 97.5% selectivity) as PdFe may inhibit the overhydrogenation of -C═C. Importantly, not only Pd, other noble metals (e.g., Pt, Ru, and Au) also showed a similar property, revealing a general rule that hydrogen spillover drives the dynamic reduction, splitting, and migration of encapsulated nanosized iron oxide, resulting in diverse structures. This study would offer a structure-controllable fabrication of high-performance magnetic nanocatalysts for various applications.

2.
Adv Mater ; 35(31): e2302793, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37208970

RESUMEN

Catalysts with designable intelligent nanostructure may potentially drive the changes in chemical reaction techniques. Herein, a multi-function integrating nanocatalyst, Pt-containing magnetic yolk-shell carbonaceous structure, having catalysis function, microenvironment heating, thermal insulation, and elevated pressure into a whole is designed, which induces selective hydrogenation within heating-constrained nanoreactors surrounded by ambient environment. As a demonstration, carbonyl of α, ß-unsaturated aldehydes/ketones are selectively hydrogenated to unsaturated alcohols with a >98% selectivity at a nearly complete conversion under mild conditions of 40 °C and 3 bar instead of harsh requirements of 120 °C and 30 bar. It is creatively demonstrated that the locally increased temperature and endogenous pressure (estimated as ≈120 °C, 9.7 bar) in the nano-sized space greatly facilitate the reaction kinetics under an alternating magnetic field. The outward-diffused products to the "cool environment" remain thermodynamically stable, avoiding the over-hydrogenation that often occurs under constantly heated conditions of 120 °C. Regulation of the electronic state of Pt by sulfur doping of carbon allows selective chemical adsorption of the CO group and consequently leads to selective hydrogenation. It is expected that such a multi-function integrated catalyst provides an ideal platform for precisely operating a variety of organic liquid-phase transformations under mild reaction conditions.

3.
Child Abuse Negl ; 129: 105642, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35509141

RESUMEN

BACKGROUND: Chinese parents and students, especially senior high school students, attach great importance to academic performance. Some studies have confirmed that childhood neglect is related to academic performance. However, the internal mechanism is relatively underexplored. OBJECTIVE: Guided by life course theory and bioecological theory, this study examined the relationship between childhood neglect and academic performance using a serial mediation model that included belief in a just world (PBJW) and academic resilience as hypothesized mediators. METHODS: A sample of 614 tenth grade students (297 males and 307 females, and 10 who did not report their sex; Mage = 15.75 years old, SD = 0.71 years old) completed questionnaires regarding demographics, childhood neglect, PBJW, academic resilience, and academic performance. RESULTS: After demographic covariates were controlled for, the results revealed that: (a) childhood neglect was negatively associated with academic performance; (b) PBJW and academic resilience mediated the link between childhood neglect and academic performance in a parallel fashion; and (c) PBJW and academic resilience also mediated the link between childhood neglect and academic performance in a sequential fashion. CONCLUSIONS: Childhood neglect is negatively related to adolescent academic performance, and the relation is mediated by PBJW and academic resilience both parallelly and sequentially.


Asunto(s)
Rendimiento Académico , Maltrato a los Niños , Adolescente , Niño , China/epidemiología , Femenino , Humanos , Lactante , Masculino , Padres , Estudiantes
4.
J Mol Histol ; 52(5): 1067-1080, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34398360

RESUMEN

Lipid metabolism is closely related to the improvement of vascular calcification (VC) in chronic kidney disease (CKD). Globular adiponectin (gAd) has been reported to be involved in the development of VC in CKD, but the detailed regulatory role remains unclear. The present study is aimed to investigate the biological function and the underlying regulation mechanism of gAd in the process of VC during CKD. Vascular smooth muscle cells (VSMCs) calcification was determined by Alizarin Red S staining. Protein signaling related with VC was tested by western blotting. The expression and intracellular localization of runt-related transcription factor 2 (Runx2) was detected by immunofluorescence and uraemic rat with VC was established by a two-step nephrectomy. Combined with the results of Alizarin Red S staining, we discovered that ß-glycerophosphate (ß-Gp)-induced the osteoblastic differentiation of VSMCs was significantly reversed by gAd treatment. Along with the VSMCs calcification and the increase of Runx2 in ß-Gp-exposed VSMCs, the activities of protein kinase B (AKT) and Wnt/ß-catenin pathway were enhanced, but that were counteracted by the exposure of gAd in rat and human VSMCs. After administration with agonists of the Wnt (SKL2001) and AKT (SC79), there appeared more osteoblastic differentiation and higher expression of Runx2 in gAd-treated VSMCs, but showing lower impact in the presence of SC79 than that in the presence of SKL2001. In the in vivo experiments, intravenous injection of gAd also significantly inhibited VC and Runx2 level in uraemic rat in a dose-dependent manner, possibly through regulating Wnt/ß-catenin pathway. This study demonstrates that gAd ameliorates osteoblastic differentiation of VSMCs possibly by blocking PI3K/AKT and Wnt/ß-catenin signaling transduction. The findings provide an important foundation for gAd in treating VC in kidney diseases.


Asunto(s)
Adiponectina/farmacología , Diferenciación Celular , Músculo Liso Vascular/citología , Miocitos del Músculo Liso/citología , Osteoblastos/citología , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Vía de Señalización Wnt , Animales , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Activación Enzimática/efectos de los fármacos , Glicerofosfatos/farmacología , Humanos , Masculino , Miocitos del Músculo Liso/efectos de los fármacos , Osteoblastos/efectos de los fármacos , Osteogénesis/efectos de los fármacos , Ratas Sprague-Dawley , Uremia/patología , Vía de Señalización Wnt/efectos de los fármacos
5.
Neurochem Int ; 148: 105110, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34166749

RESUMEN

As a subjective mood-related disorder with an unclear mechanism, depression has many problems in its diagnosis, which offers great space and value for research. At present, the methods commonly used to judge whether an animal model of depression has been established are mainly by biochemical index detection and behavioral tests, both of which inevitably cause stress in animals. Stress-induced hair growth inhibition has been widely reported in humans and animals. The simplicity of collecting hair samples and the observable state of hair growth has significant advantages; we tried to explore whether the parameters related to hair growth could be used as auxiliary indicators to evaluate a depression model in animals. The length and weight of the hair were calculated. Correlation analysis was conducted between the depressive behavioral results and the glucocorticoid levels in hair and serum. Learned helplessness combined with chronic restraint stress, and chronic unpredictable stress in the animal were detectable by superficial observation, weight ratio, and length of hair, and follicular development scores were significantly reduced compared to the control. The hair growth parameters of rats with depression, the rise in corticosterone, and the corresponding changes in behavioral parameters were significantly correlated. The neurotrophic factors, glucocorticoid-receptor (GR), brain-derived neurotrophic factor (BDNF), fibroblast growth factor 2 (FGF2), and fibroblast growth factor 5 (FGF5), are associated with depression and hair growth. Significant differences were detected between the stress and control groups, suggesting that the mechanism underlying the stress-phenomenon inhibition of hair growth may be related to growth factor mediation.


Asunto(s)
Depresión/psicología , Cabello/crecimiento & desarrollo , Estrés Psicológico/psicología , Animales , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor 2 de Crecimiento de Fibroblastos/metabolismo , Factor 5 de Crecimiento de Fibroblastos/metabolismo , Glucocorticoides/metabolismo , Cabello/química , Folículo Piloso/crecimiento & desarrollo , Desamparo Adquirido , Masculino , Fenotipo , Ratas , Ratas Sprague-Dawley , Receptores de Glucocorticoides/metabolismo , Restricción Física
6.
Pharmacol Res ; 163: 105232, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33027716

RESUMEN

Patients with colorectal cancer treated with 5-fluorouracil (5-FU) and irinotecan (CPT-11) exhibit a risk for chemotherapy-induced colitis (CIC) that may lead to fatal consequences. Cryptotanshinone (CTS) is a natural compound extracted from the root of Salvia miltiorrhiza Bunge that shows potent antitumor activities. We previously reported CTS relieved 5-FU/ CPT-11 induced colitis in tumor-free mice. In this study, we studied the effect of CTS on 5-FU/ CPT-11 induced colitis in mice with colitis associated colon cancer (CAC). The effects of CTS on CIC were evaluated by disease activity index (DAI) and histological assessment via hematoxylin-and-eosin staining. Serum lipids and lipid-metabolic enzymes were detected by commercial kits. Fecal microbial diversity was detected by 16S ribosomal RNA gene sequencing. To find the role of fecal bacteria in CAC mice with 5-FU/ CPT-11 induced colitis, pseudo-germ-free mice were established by intragastric administration of mixed antibiotics. Except for decreasing tumor number (3 ± 1 vs 6 ± 1, p < 0.05), CTS significantly alleviated DAI (1.9 ± 0.6 vs 2.6 ± 0.5, p < 0.05) and regulated serum lipids in CAC mice with 5-FU/ CPT-11induced colitis. Compared with model group, CTS significantly increased serum triglycerides (TG) (1.13 ± 0.26 mM vs 0.79 ± 0.03 mM, p < 0.05), high density lipoprotein (HDL) (3.88 ± 0.1 mM vs 3.28 ± 0.05 mM, p < 0.001) and oxidized low-density lipoprotein (oxLDL) (288.12 ± 65.92 ng/mL vs 150.72 ± 42.13 ng/mL, p < 0.05) level but decreased serum adiponectin level (1177.47 ± 179.2 pg/mL vs 1523.43 ± 91.8 pg/mL, p < 0.05). Among fecal bacteria significantly correlated with lipid metabolism, CTS significantly decreased the abundance of g__norank_f__Muribaculaceae (21.15 % ± 5.7 % vs 41.84 ± 12.0 %, p < 0.01) but increased that of g_Lactobacillus (11.13 % ± 6.6 % vs 5.7 % ± 4.6 %, p < 0.05), g__Alistipes (3.66 % ± 0.7 % vs 1.47 % ± 1,0%, p < 0.01) and g__Odoribacter (1.31 % ± 0.7 % vs 0.30 % ± 0.2 %, p < 0.01). In addition, the development of CIC and abnormal lipid metabolism were significantly prevented in pseudo-germ-free mice. Therefore, we concluded CTS alleviated 5FU/CPT-11 induced colitis in CAC mice via regulating fecal flora associated lipid metabolism.


Asunto(s)
Antiinflamatorios/uso terapéutico , Colitis/tratamiento farmacológico , Neoplasias del Colon/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Metabolismo de los Lípidos/efectos de los fármacos , Fenantrenos/uso terapéutico , Animales , Antiinflamatorios/farmacología , Antineoplásicos , Bacterias/efectos de los fármacos , Bacterias/genética , Bacterias/metabolismo , Colitis/inducido químicamente , Colitis/microbiología , Colitis/patología , Colon/efectos de los fármacos , Colon/patología , Neoplasias del Colon/microbiología , Neoplasias del Colon/patología , Heces/microbiología , Fluorouracilo , Microbioma Gastrointestinal/genética , Irinotecán , Masculino , Ratones Endogámicos BALB C , Fenantrenos/farmacología , ARN Ribosómico 16S
7.
Turk Pediatri Ars ; 55(3): 334, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33061768
8.
Exp Ther Med ; 18(5): 3737-3740, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31656537

RESUMEN

Intellectual disability (ID) is a non-specific phenotype present in a genetically heterogeneous group of disorders. The genetic cause of ID remains elusive in the majority of patients due to this extreme heterogeneity. Whole exome sequencing technology has been applied to identify pathogenic gene variants responsible for ID. The present report described a 1.7-year-old female patient who had severe ID with the specific features of delayed motor development, language disorders and abnormal facial features. Exome analysis identified a novel pathogenic variant of the SETD5 gene [c.2025_2026delAG (p.Gly676Valfs*2)]. The variant was a frameshift mutation, causing termination of the protein in advance. These findings indicated that this mutation of the SETD5 gene may be a genetic cause for ID. The present study aimed to provide a meaningful exploration of ID and the identification of clinical core genetic pedigrees.

9.
Turk Pediatri Ars ; 54(2): 125-128, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31384148

RESUMEN

Teratoma is a rare tumor of the central nervous system that belongs to intracranial germ cell tumors. We report a 2-month-old male child with an immature teratoma of the posterior fossa. Physical and laboratory examinations were normal. Though a radiologic examination was characteristic for this neoplasm, it was insufficient to make a definite diagnosis. Combining the radiologic findings with a histopathologic examination contributed to diagnosing immature teratoma and differentiating it from other subtypes of intracranial germ cell tumors. Our aim was to provide a greater understanding of immature teratoma by reporting this case.


Teratom, merkezi sinir sisteminin nadir görülen bir tümörü olup intrakranial germ hücreli tümörlerden birisidir. Bu makalede, posterior fossanin immatür teratomu bulunan 2 aylik bir erkek çocugu sunmaktayiz. Fizik baki ve laboratuvar bulgulari normal saptandi. Radyolojik inceleme bu neoplazma açisindan belirgin bulunmasina ragmen, kesin tani koymak için yetersizdi. Radyolojik bulgularin histopatolojik inceleme ile birlestirilmesi, immatür teratomun tanisina ve immatür teratomun intrakraniyal germ hücreli tümörlerinin diger alt türlerinden ayirt edilmesine katkida bulunmustur. Bu olguyu sunarak, immatür teratomun daha iyi anlasilmasini saglamayi amaçladik.

10.
Biomed Res Int ; 2019: 9105768, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31016203

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the effects of bone marrow stromal stem cells (BMSCs) on renal ischemia-reperfusion injury (RIRI) and dynamically monitor engrafted BMSCs in vivo for the early prediction of their therapeutic effects in a rat model. METHODS: A rat model of RIRI was prepared by clamping the left renal artery for 45 min. One week after renal artery clamping, 2 × 106 superparamagnetic iron oxide- (SPIO-) labeled BMSCs were injected into the renal artery. Next, MR imaging of the kidneys was performed on days 1, 7, 14, and 21 after cell transplantation. On day 21, after transplantation, serum creatinine (Scr) and urea nitrogen (BUN) levels were assessed, and HE staining and TUNEL assay were also performed. RESULTS: The body weight growth rates in the SPIO-BMSC group were significantly higher than those in the PBS group (P < 0.05), and the Scr and BUN levels were also significantly lower than those in the PBS group (P < 0.05). HE staining showed that the degree of degeneration and vacuole-like changes in the renal tubular epithelial cells in the SPIO-BMSC group was significantly better than that observed in the PBS group. The TUNEL assay showed that the number of apoptotic renal tubular epithelial cells in the SPIO-BMSC group was significantly lower than that in the PBS group. The T2 value of the renal lesion was the highest on day 1 after cell transplantation, and it gradually decreased with time in both the PBS and SPIO-BMSC groups but was always the lowest in the SPIO-BMSC group. CONCLUSION: SPIO-labeled BMSC transplantation can significantly promote the recovery of RIRI and noninvasive dynamic monitoring of engrafted cells and can also be performed simultaneously with MRI in vivo for the early prediction of therapeutic effects.


Asunto(s)
Células de la Médula Ósea/citología , Riñón/patología , Células Madre Mesenquimatosas/citología , Daño por Reperfusión/patología , Animales , Medios de Contraste/administración & dosificación , Modelos Animales de Enfermedad , Femenino , Imagen por Resonancia Magnética/métodos , Nanopartículas de Magnetita/administración & dosificación , Trasplante de Células Madre Mesenquimatosas/métodos , Ratas , Ratas Sprague-Dawley , Arteria Renal/patología , Coloración y Etiquetado/métodos
11.
Ital J Pediatr ; 45(1): 37, 2019 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-30867013

RESUMEN

BACKGROUND: Neural tube defects (NTDs) are birth defects of the brain, spine, or spinal cord invoked by the insufficient intake of folic acid in the early stages of pregnancy and have a complex etiology involving both genetic and environmental factors. So the study aimed to explore the association between alterations in maternal one-carbon metabolism and NTDs in the offspring. METHODS: We conducted a case-control study to get a deeper insight into this association, as well as into the role of genetic polymorphisms. Plasma concentrations of folate, homocysteine (Hcy), S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH) and genotypes and alleles distributions of 52 SNPs in 8 genes were compared for 61 women with NTDs-affected offspring and 61 women with healthy ones. RESULTS: There were significant differences between groups with regard to plasma folate, SAM, SAH and SAM/SAH levels. Logistic regression results revealed a significant association between maternal plasma folate level and risk of NTDs in the offspring. For MTHFD1 rs2236225 polymorphism, mothers having GA genotype and A allele exhibited an increased risk of NTDs in the offspring (OR = 2.600, 95%CI: 1.227-5.529; OR = 1.847, 95%CI: 1.047-3.259). For MTHFR rs1801133 polymorphism, mothers having TT and CT genotypes were more likely to affect NTDs in the offspring (OR = 4.105, 95%CI: 1.271-13.258; OR = 3.333, 95%CI: 1.068-10.400). Moreover, mothers carrying T allele had a higher risk of NTDs in the offspring (OR = 1.798, 95%CI: 1.070-3.021). For MTRR rs1801394 polymorphism, the frequency of G allele was significantly higher in cases than in controls (OR = 1.763, 95%CI: 1.023-3.036). Mothers with NTDs-affected children had higher AG genotype in RFC1 rs1051226 polymorphism than controls, manifesting an increased risk for NTDs (OR = 3.923, 95%CI: 1.361-11.308). CONCLUSION: Folic acid deficiency, MTHFD1 rs2236225, MTHFR rs1801133, MTRR rs1801349 and RFC1 rs1051226 polymorphisms may be maternal risk factors of NTDs.


Asunto(s)
Deficiencia de Ácido Fólico/genética , Predisposición Genética a la Enfermedad/epidemiología , Defectos del Tubo Neural/genética , Polimorfismo de Nucleótido Simple/genética , Adulto , Carbono/metabolismo , Estudios de Casos y Controles , Distribución de Chi-Cuadrado , China , Femenino , Ferredoxina-NADP Reductasa/genética , Deficiencia de Ácido Fólico/diagnóstico , Deficiencia de Ácido Fólico/epidemiología , Marcadores Genéticos/genética , Genotipo , Humanos , Recién Nacido , Modelos Logísticos , Masculino , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Antígenos de Histocompatibilidad Menor/genética , Defectos del Tubo Neural/epidemiología , Defectos del Tubo Neural/fisiopatología , Oportunidad Relativa , Embarazo , Valores de Referencia
12.
RSC Adv ; 9(60): 35003-35010, 2019 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-35530687

RESUMEN

Stem cell imaging in vivo is critical to elucidate the homing, distribution, survival, and repair mechanisms and to evaluate the therapeutic effects of engrafted stem cells. Unfortunately, unimodal imaging of stem cells does not simultaneously satisfy all current requirements owing to their intrinsic limitations. Obviously, bimodal or multimodal imaging of stem cells is a promising strategy for circumventing this issue. This study aimed to design and synthesize a novel dual-modal polyethylene glycol-modified magnetic nanoparticle (Fe3+-PEG-MNP) based on natural biomaterials including melanin and Fe ions for photoacoustic (PA) and magnetic resonance (MR) imaging of stem cells in vivo. The Fe3+-PEG-MNPs were characterized and their PA/MR imaging capability and cytotoxicity were evaluated. Bone marrow mesenchymal stem cells (BM-MSCs) labeled with Fe3+-PEG-MNPs were subjected to PA and MR imaging in vitro and in vivo. Consequently, Fe3+-PEG-MNPs displayed many superior properties, including ultra-small particle size, higher stability, water solubility, easy labeling of cells, lower cytotoxicity, high biosafety, excellent capability of PA/MR imaging, high sensitivity and long-term monitoring in vitro and in vivo. In particular, PA and MR signals of labeled BM-MSCs were maintained for at least 35 and 28 d, respectively, in vivo. Therefore, Fe3+-PEG-MNPs are ideal dual-modal PA/MR nanoparticles for non-invasive and effective monitoring of engrafted stem cells in vivo.

13.
Pediatr Neurosurg ; 53(6): 401-406, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30391955

RESUMEN

Choroid plexus papilloma (CPP) is a rare benign tumor of the central nervous system. Bilateral lateral ventricle CPP is extremely uncommon. In this case report, we described a case of bilateral lateral ventricle CPP in a 4-month-old female patient conceived by in vitro fertilization (IVF). Neurological examination and imaging were performed. In neurological examination, meningeal irritation signs and sunset phenomenon were positive. Brain computed tomography (CT) and magnetic resonance imaging (MRI) displayed masses located in the trigone of the bilateral lateral ventricle with hydrocephalus. Contrast-enhanced MRI showed intense homogeneous enhancement. The diagnoses of bilateral lateral ventricle CPP related to hydrocephalus and extravasation of cerebrospinal fluid (CSF) were made. Repeated surgical procedures via parietotemporal craniotomy were performed, and the diagnosis was confirmed by histopathology examination. The patient presented with delayed development during a follow-up period of 1 year. In conclusion, imaging is an effective approach of investigation. CPP could be highly suspected according to the features of hydrocephalus, lobulated appearance, and homogeneous enhancement on imaging. Total surgical removal is a valid curative method for CPP.


Asunto(s)
Neoplasias del Ventrículo Cerebral/cirugía , Ventrículos Laterales/diagnóstico por imagen , Ventrículos Laterales/patología , Papiloma del Plexo Coroideo/diagnóstico por imagen , Papiloma del Plexo Coroideo/patología , Neoplasias del Ventrículo Cerebral/patología , Femenino , Fertilización In Vitro , Humanos , Hidrocefalia/líquido cefalorraquídeo , Hidrocefalia/patología , Hidrocefalia/cirugía , Lactante , Ventrículos Laterales/cirugía , Imagen por Resonancia Magnética , Papiloma del Plexo Coroideo/cirugía , Tomografía Computarizada por Rayos X
14.
Int J Nanomedicine ; 13: 1749-1759, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29606868

RESUMEN

BACKGROUND: Melanin and manganese are both indispensable natural substances that play crucial roles in the human body. Melanin has been used as a multimodality imaging nanoplatform for biology science research because of its natural binding ability with metal ions (eg, 64Cu2+, Fe3+, and Gd3+). Because of its effects on T1 signal enhancement, Mn-based nanoparticles have been used in magnetic resonance (MR) quantitative cell tracking in vivo. Stem cell tracking in vivo is an essential technology used to characterize engrafted stem cells, including cellular viability, biodistribution, differentiation capacity, and long-term fate. METHODS: In the present study, manganese(II) ions chelated to melanin nanoparticles [MNP-Mn(II)] were synthesized. The characteristics, stem cell labeling efficiency, and cytotoxicity of the nanoparticles were evaluated. MR imaging of the labeled stem cells in vivo and in vitro were also further performed. In T1 relaxivity (r1), MNP-Mn(II) were significantly more abundant than Omniscan. Bone marrow-derived stem cells (BMSCs) can be labeled easily by coincubating with MNP-Mn(II), suggesting that MNP-Mn(II) had high biocompatibility. RESULTS: Cell Counting Kit-8 assays revealed that MNP-Mn(II) had almost no cytotoxicity when used to label BMSCs, even with a very high concentration (1,600 µg/mL). BMSCs labeled with MNP-Mn(II) could generate a hyperintense T1 signal both in vitro and in vivo, and the hyperintense T1 signal in vivo persisted for at least 28 days. CONCLUSION: Taken together, our results showed that MNP-Mn(II) possessed many excellent properties for potential quantitative stem cell tracking in vivo.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Manganeso/química , Melaninas/química , Nanopartículas/química , Células Madre/citología , Animales , Materiales Biocompatibles/química , Diferenciación Celular , Quelantes/química , Masculino , Nanopartículas/uso terapéutico , Ratas Sprague-Dawley , Distribución Tisular
15.
J Biomed Mater Res A ; 105(1): 131-137, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27588709

RESUMEN

Tracking transplanted stem cells is necessary to clarify cellular properties and improve transplantation success. In this study, we designed and synthesized melanin-based gadolinium3+ (Gd3+ )-chelate nanoparticles (MNP-Gd3+ ) of ∼7 nm for stem cell tracking in vivo. MNP-Gd3+ possesses many beneficial properties, such as its high stability and sensitivity, shorter T1 relaxation time, higher cell labeling efficiency, and lower cytotoxicity compared with commercial imaging agents. We found that the T1 relaxivity (r1 ) of MNP-Gd3+ was significantly higher than that of Gd-DTPA; the nanoparticles were taken up by bone mesenchymal stem cells (BMSCs) via endocytosis and were broadly distributed in the cytoplasm. Based on an in vitro MTT assay, no cytotoxicity of labeled stem cells was observed for MNP-Gd3+ concentrations of less than 800 µg/mL. Furthermore, we tracked MNP-Gd3+ -labeled BMSCs in vivo using 3.0T MRI equipment. After intramuscular injection, MNP-Gd3+ -labeled BMSCs were detected, even after four weeks, by 3T MRI. We concluded that MNP-Gd3+ nanoparticles at appropriate concentrations can be used to effectively monitor and track BMSCs in vivo. MNP-Gd3+ nanoparticles have potential as a new positive MRI contrast agent in clinical applications. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 131-137, 2017.


Asunto(s)
Células de la Médula Ósea/citología , Rastreo Celular/métodos , Medios de Contraste , Gadolinio , Imagen por Resonancia Magnética/métodos , Melaninas , Células Madre Mesenquimatosas/citología , Nanopartículas , Animales , Células de la Médula Ósea/metabolismo , Medios de Contraste/química , Medios de Contraste/farmacología , Gadolinio/química , Gadolinio/farmacología , Ensayo de Materiales , Melaninas/química , Melaninas/farmacología , Células Madre Mesenquimatosas/metabolismo , Nanopartículas/química , Nanopartículas/uso terapéutico , Ratas , Ratas Sprague-Dawley
16.
Yao Xue Xue Bao ; 51(3): 444-9, 2016 03.
Artículo en Chino | MEDLINE | ID: mdl-29859027

RESUMEN

The study aims to develop a rapid, specific and sensitive method for quantitative analysis of trace impurities in levofloxacin formulation using LC-MS/MS. The quality of the different formulations from 19 plants was evaluated in the contents of the impurities. The results indicated that there were 5 impurities in the samples, and the content was different in the products with same formulation by different plants. The products of 3 plants were in good quality with impurities level under 0.01%. Levofloxacin N(4')-methyl quaternary impurity was first reported as the formulation impurity. The impurities were tightly correlated to the reservation of drug, process control of formulation and storage during transportation. The results suggest that our method is sensitive and specific to detect the trace impurities in formulation, and can be used to monitor the quality of commercial drug product.


Asunto(s)
Contaminación de Medicamentos , Levofloxacino/análisis , Levofloxacino/normas , Cromatografía Liquida , Espectrometría de Masas en Tándem
17.
Yao Xue Xue Bao ; 51(10): 1564-71, 2016 10.
Artículo en Chino | MEDLINE | ID: mdl-29932601

RESUMEN

The research aimed to investigate the suppression effect of Mai Shu which contains hawthorn, hippophae, medlar, phytosterols(ß-sitosterol, stigmasterol and campesterol), ß-glucan and lycopeneon formation of atherosclerotic plaque in apolipoprotein E knock-out (ApoE-/-) mice. Liquid chromatography-ultravioletmass spectrometry(LC-UV-MC) methods were used to analyze the main chemical composition of Mai Shu. Atherosclerotic mice models were established by high-fat diet. The mice were administrated with Mai Shu (1, 2, 4 g·kg-1·d-1) or other contrast materials by intragastric route for 10 weeks continuously. At the end of administration, the blood of mice was collected for tests of the serum total cholesterol(TC), total triglyceride(TG) and high density lipoprotein cholesterol(HDL-C) level. Atherosclerotic lesions in aorta and aortic root were assessed by calculating the relative area of lesions(oil red O stained). Intravital fluorescence microscopic system was used to evaluate the leukocyte-endothelial adhesion in mesenteric artery of mice by detecting the rolling velocity of white blood cells(WBC). Collagenous fibers and macrophages in lesions were detected by sirius red staining and immunological histological chemistry to evaluate the atherosclerotic plaque stability. Results showed that Mai Shu contains various flavonoids(9.5%), phytosterols(23.8%) and polysaccharides(8.9%). The serum lipid level of model animals was significantly higher than the control animals. Serum TC level was decreased by Mai Shu (4 g·kg-1, P < 0.001) compared to the untreated model. Serum TG level was reduced by Mai Shu (1, 2, 4 g·kg-1) compared to model(P < 0.01). Area of atherosclerotic lesions in aorta and aortic root was decreased in Mai Shu group (aorta: 1 g·kg-1, P < 0.05; 2 g·kg-1, P < 0.01; 4 g·kg-1, P < 0.001; aortic root: 2, 4 g·kg-1, P < 0.01). Rolling velocity of white blood cells of Mai Shu (4 g·kg-1, P < 0.001) group was increased over the untreated model. Collagenous fibers in lesions were observationally increased by Mai Shu (1, 2 g·kg-1) and macrophages were decreased (2, 4 g·kg-1) compared to model. These results demonstrate that Mai Shu can obviously decrease the serum lipid levels and the risk of leukocyte-endothelial adhesion in ApoE-/- mice. The effect of Mai Shu may be associated with the decrease of macrophages in plaque.


Asunto(s)
Aterosclerosis/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Placa Aterosclerótica/tratamiento farmacológico , Animales , Aorta/patología , Colesterol/sangre , Dieta Alta en Grasa , Modelos Animales de Enfermedad , Macrófagos/citología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados para ApoE , Fitosteroles/farmacología , Triglicéridos/sangre
18.
Stem Cells Int ; 2016: 2018474, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26649047

RESUMEN

Despite advances in our understanding of spinal cord injury (SCI) mechanisms, there are still no effective treatment approaches to restore functionality. Although many studies have demonstrated that transplanting NT3 gene-transfected bone marrow-derived mesenchymal stem cells (BMSCs) is an effective approach to treat SCI, the approach is often low efficient in the delivery of engrafted BMSCs to the site of injury. In this study, we investigated the therapeutic effects of magnetic targeting of NT3 gene-transfected BMSCs via lumbar puncture in a rat model of SCI. With the aid of a magnetic targeting cells delivery system, we can not only deliver the engrafted BMSCs to the site of injury more efficiently, but also perform cells imaging in vivo using MR. In addition, we also found that this composite strategy could significantly improve functional recovery and nerve regeneration compared to transplanting NT3 gene-transfected BMSCs without magnetic targeting system. Our results suggest that this composite strategy could be promising for clinical applications.

19.
Zhongguo Zhong Yao Za Zhi ; 40(5): 894-6, 2015 Mar.
Artículo en Chino | MEDLINE | ID: mdl-26087552

RESUMEN

A new sesquiterpenoid, 8α-hydroxy-6ß-methoxy-1-oxoeremophila-7 (11), 9 (10) -diene-12, 8-olide (1) and five known compounds, petasin (2), caffeic acid (3), hepta-cosanol (4), ß-sitosterol (5) and ß-daucosterol (6) have been isolated from the roots of Ligularia intermedia. The compounds were isolated by column chromatography on silica gel and Sephadex LH-20, and identified based on spectral analyses (MS, 1H-NMR, 13C-NMR).


Asunto(s)
Asteraceae/química , Medicamentos Herbarios Chinos/química , Raíces de Plantas/química , Medicamentos Herbarios Chinos/aislamiento & purificación , Imagen por Resonancia Magnética , Estructura Molecular , Espectrometría de Masa por Ionización de Electrospray
20.
Neural Regen Res ; 10(3): 404-11, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25878588

RESUMEN

An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7-8. Superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesenchymal stem cells reached the lesion site in these rats than in those without magnetic guidance or superparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan (BBB) locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guidance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

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