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1.
Chirality ; 35(12): 983-992, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37464916

RESUMO

Fluoxetine (FLT) is a widely used antidepressant in clinical practice, which can be metabolized into active norfluoxetine (NFLT) in vivo. The stereoselectivity of FLT and NFLT enantiomers across the blood-brain barrier (BBB) is still to be clarified. In this study, accurate and reliable UPLC-MS/MS enantioselective analysis was established in rat plasma and brain. The characteristics of FLT and NFLT enantiomers across the BBB were studied by chemical knockout of rat transporters. We found that the dominant enantiomers of FLT and NFLT were S-FLT and R-NFLT, respectively, both in plasma and in brain. The FLT and NFLT enantiomers showed significant stereoselectivity across the BBB, and S-FLT and S-NFLT were the dominant configurations across the BBB. Chemical knockout of organic cation transporter 1 (OCT1) and OCT3 can affect the ratio of plasma FLT and NFLT enantiomers into the brain, suggesting that OCT1/3 is stereoselective for FLT and NFLT transport across the BBB.


Assuntos
Fluoxetina , Transportador 1 de Cátions Orgânicos , Ratos , Animais , Fluoxetina/análise , Fluoxetina/metabolismo , Transportador 1 de Cátions Orgânicos/metabolismo , Barreira Hematoencefálica , Cromatografia Líquida/métodos , Estereoisomerismo , Espectrometria de Massas em Tandem/métodos
2.
J Control Release ; 358: 78-97, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37076016

RESUMO

The establishment of in vitro models of the BBB is significant for the evaluation of the mechanism and permeability of drugs and their sustained-release formulations across the BBB. Among the different models, the immortalized human cell line hCMEC/D3 has the potential to be used for a standardized in vitro BBB model due to its high throughput, reproducibility, homology and low cost. The high permeability of the paracellular pathway and the low expression of both certain transporters and metabolic enzymes in this model lead to low physiological levels of physical, transport and metabolic barriers, thus limiting the application of these cells. The barrier properties of this model have been improved in different studies by various means. However, no systematic review has been conducted on the optimization of model-building conditions or on the regulation and expression of transporters in the models. Some existing reviews focus on the overall description of the entire field of blood-brain barrier in vitro models, lacking in-depth and systematic reviews on the experimental details and model evaluation methods based on hCMEC/D3.This paper deals with a detailed review on the optimization of multiple aspects and modalities of the hCMEC/D3 cell culture process, including initial medium, optimal serum levels, Transwell membrane materials, supra-membrane supports, inoculum density, endogenous growth factor, exogenous drug levels, co-culture and transfection methods, to provide references for the establishment and evaluation of hCMEC/D3 cell models.


Assuntos
Barreira Hematoencefálica , Células Endoteliais , Humanos , Barreira Hematoencefálica/metabolismo , Reprodutibilidade dos Testes , Células Endoteliais/metabolismo , Transporte Biológico , Linhagem Celular
3.
Sci Total Environ ; 875: 162563, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36870511

RESUMO

Low-molecular-weight organic acids (LMWOAs) prevalent in soil environments may influence the transport, fate, and orientation of microplastics (MPs) by mediating mineral interfaces. Nevertheless, few studies have reported their impact on the environmental behavior of MPs in soil. Here, the functional regulation of oxalic at mineral interfaces and its stabilizing mechanism for MPs were investigated. The results showed that oxalic drove MPs stability onto minerals and new adsorption pathways, which are dependent on the bifunctionality of minerals induced by oxalic acid. Besides, our findings reveal that in the absence of oxalic acid, the stability of hydrophilic and hydrophobic MPs on kaolinite (KL) mainly displays hydrophobic dispersion, whereas electrostatic interaction is dominant on ferric sesquioxide (FS). Moreover, the amide functional groups ([NHCO]) of PA-MPs may have positive feedback on the stability of MPs. In the presence of oxalic acid (2-100 mM), the MPs stability efficiency and property onto minerals were integrally increased in batch studies. Our results demonstrate the oxalic acid-activated interfacial interaction of minerals via dissolution coupled O-functional groups. Oxalic-induced functionality at mineral interfaces further activates electrostatic interaction, cation bridge effect, hydrogen forces, ligand exchange and hydrophobicity. These findings provide new insights into the regulating mechanisms of oxalic-activated mineral interfacial properties for environmental behavior of emerging pollutants.

4.
iScience ; 25(6): 104399, 2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35633943

RESUMO

The paper explores options for a 2050 carbon free energy future for India. Onshore wind and solar sources are projected as the dominant primary contributions to this objective. The analysis envisages an important role for so-called green hydrogen produced by electrolysis fueled by these carbon free energy sources. This hydrogen source can be used to accommodate for the intrinsic variability of wind and solar complementing opportunities for storage of power by batteries and pumped hydro. The green source of hydrogen can be used also to supplant current industrial uses of gray hydrogen produced in the Indian context largely from natural gas with important related emissions of CO2. The paper explores further options for use of green hydrogen to lower emissions from otherwise difficult to abate sectors of both industry and transport. The analysis is applied to identify the least cost options to meet India's zero carbon future.

5.
Dis Markers ; 2022: 4317480, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432631

RESUMO

Thyroid cancer (TC) is prone to recurrence, and biomarkers for predicting progression-free interval (PFI) are poorly explored. The study investigates the predictive value and underlying biological mechanisms of lncRNA CDKN2B-AS1 in TC. Combining RNA-seq and survival data, we identified that CDKN2B-AS1 was upregulated in TC samples and could be an excellent prognostic indicator. To exclude confounding factors, we divided patients into different subgroups using median CDKN2B-AS1 expression, and the effects of CDKN2B-AS1 on PFI and clinical features were explored in different clinical subgroups. Meanwhile, ssGSEA and ESTIMATE algorithms revealed that CDKN2B-AS1 overexpression may suggest the active state of the immune microenvironment. On the other hand, enrichment analysis also proved the potential influence of CDKN2B-AS1 on immune regulation in TC. Finally, we created a CDKN2B-AS1, microRNAs, and TFs network and discovered a new biomarker (CDKN2B-AS1) that might be employed as a therapeutic target in TC patients.


Assuntos
MicroRNAs , RNA Longo não Codificante , Neoplasias da Glândula Tireoide , Linhagem Celular Tumoral , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , Prognóstico , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Neoplasias da Glândula Tireoide/genética , Microambiente Tumoral/genética
6.
Micromachines (Basel) ; 14(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36677134

RESUMO

Diamond coatings were deposited on PCB (printed circuit board) carbide milling tool substrates under various schemes of acid and alkali pretreatment by hot filament chemical vapor deposition (HFCVD). Scanning electron microscopy and X-ray coating analysis were used to examine the surface morphology of the milling tools and the impact of de-cobalt from the substrate surface after pretreatment. Milling experiments were carried out to study the cutting performance of diamond-coated PCB micro-milling tools under various pretreatment processes. The results show that abrasive wear, coating flaking, and cutting-edge chipping are the main failure forms of coated PCB milling tools. The substrate pretreatment process with 20 min of alkali etching followed by 20 s of acid etching allows the diamond-coated micro-milling tools to produce the best film-substrate adhesion and substrate strength. These milling tools also have the longest service lives and are suitable for the high-speed cutting processing of PCB.

7.
Nat Commun ; 12(1): 6953, 2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34845233

RESUMO

The Japanese government has announced a commitment to net-zero greenhouse gas emissions by 2050. It envisages an important role for hydrogen in the nation's future energy economy. This paper explores the possibility that a significant source for this hydrogen could be produced by electrolysis fueled by power generated from offshore wind in China. Hydrogen could be delivered to Japan either as liquid, or bound to a chemical carrier such as toluene, or as a component of ammonia. The paper presents an analysis of factors determining the ultimate cost for this hydrogen, including expenses for production, storage, conversion, transport, and treatment at the destination. It concludes that the Chinese source could be delivered at a volume and cost consistent with Japan's idealized future projections.

8.
BMC Endocr Disord ; 21(1): 193, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34563184

RESUMO

BACKGROUND: Variants of chromodomain helicase DNA binding protein 7 (CHD7) gene are commonly associated with Kallmann syndrome (KS) and account for 5-6% of idiopathic hypogonadotropic hypogonadism (IHH) cases. Here we report a novel mutation of CHD7 gene in a patient with KS, which may contribute to the better understanding of KS. CASE PRESENTATION: A 29-year-old male patient with KS and a chief complaint of delayed puberty for 13 years (Tanner B Stage< 4) was admitted to the Department of Endocrinology of the First Affiliated Hospital of Zhejiang University (Hangzhou, China) in September 2019. Dual-energy X-ray absorptiometry (DEXA) showed low bone density in both lumbar spine (L1 ~ L5 mean Z-score - 3.0) and femoral neck (Z-score - 2.7). Dynamic contrast-enhanced magnetic resonance imaging (MRI) of pituitary and contrast-enhanced computed tomography (CT) showed no abnormal findings. Ophthalmological evaluation showed that his both eyes showed exotropia, and no sight loss was noted. Heterozygous c.1619G > T mutation of TCD7 gene (p.G4856V) was detected, whereas none of his family members had this mutation. Human chorionic gonadotropin (HCG) and human menopausal gonadotropin (HMG) were injected for three times/week to treat idiopathic hypogonadotropic hypogonadism (IHH). After several months of therapy, the patient's health condition improved. His testicles became larger, and his secondary sexual characteristics improved after treatment. CONCLUSION: Exploration of the novel splice-site mutation of CHD7 may further our current understanding of KS.


Assuntos
DNA Helicases/genética , Proteínas de Ligação a DNA/genética , Síndrome de Kallmann/genética , Mutação de Sentido Incorreto , Adulto , China , Análise Mutacional de DNA , Heterozigoto , Humanos , Hipogonadismo/diagnóstico , Hipogonadismo/genética , Hipogonadismo/terapia , Síndrome de Kallmann/complicações , Síndrome de Kallmann/diagnóstico , Síndrome de Kallmann/terapia , Imageamento por Ressonância Magnética , Masculino , Polimorfismo de Nucleotídeo Único , Puberdade Tardia/diagnóstico , Puberdade Tardia/etiologia , Puberdade Tardia/genética , Puberdade Tardia/terapia , Tomografia Computadorizada por Raios X
9.
J Int Med Res ; 48(10): 300060520961684, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33045897

RESUMO

Autoimmune polyglandular syndrome (APS) is a rare disease that is characterized by autoimmune reactions to multiple endocrine and non-endocrine organs, which can be divided into four main types. The principal manifestations of APS-3 are autoimmune thyroid disease and other autoimmune diseases, such as type 1 diabetes, atrophic gastritis, pernicious anemia, vitiligo, alopecia, and myasthenia gravis, but not Addison's disease or hypoparathyroidism. Here we report a case demonstrating the rare coexistence of growth hormone deficiency and hyperthyroidism with sexual dysgenesis, secondary amenorrhea, cardiomegaly, splenomegaly, hypoproteinemia, pleural effusion, seroperitoneum, pericardial effusion, anasarca, osteoporosis, vitamin D deficiency, iron-deficiency anemia, poor blood coagulation, leucocytopenia, peripheral neuropathy, hyperuricemia, ichthyosis, tinea cruris, and onychomycosis.


Assuntos
Doença de Addison , Hipertireoidismo , Poliendocrinopatias Autoimunes , Síndrome de Turner , Feminino , Hormônio do Crescimento , Humanos , Hipertireoidismo/complicações , Poliendocrinopatias Autoimunes/complicações
10.
Biosens Bioelectron ; 165: 112336, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32729480

RESUMO

Early and accurate disease diagnosis is of great appeal for saving patients' life, but requires biomarkers to be sensitively detected with simplicity, convenience, and low cost. Exploring the development of a high-performance fluorescence biosensor for biomarkers solid, equipment-free and visual biosensing is highly urgent but faces enormous challenges. Herein, we proposed a brand-new fluorescence system by integrating a typical aggregation induced emission dye (TPE-BTD) with dopamine for multiple biomarkers sensitive detection based on target-induced catalyzing oxidation. The system comprising TPE-BTD and dopamine emits strong fluorescence; with horseradish peroxidase (HRP) or HRP-mimicking DNAzyme and H2O2 being added, significant oxidation on dopamine occurs to generate dopachrome, which actuated the inner filter effect (IFE) due to the overlap of its absorbtion curve and emission spectrum of TPE-BTD, subsequently decreasing fluorescence emission and displaying a rapid and sensitive response to H2O2 and G-quadruplex DNA. We further apply TPE-BTD/dopamine system in analysis of glucose and DNA adenine methylation methyltransferase (Dam MTase) based on target-initiated signal transduction. Finally, TPE-BTD was employed as emitters in fabrication of paper biosensors, which can achieve solid, equipment-free and visual detection of multiple biomarkers based on the high emission performance of TPE-BTD, opening up a new pathway to development of biosensors for practical application. We expect this sensing conception will be helpful in development of practical biosensors, and this sensor will find more applications in disease diagnosis.


Assuntos
Técnicas Biossensoriais , DNA Catalítico , Quadruplex G , Biomarcadores , Humanos , Peróxido de Hidrogênio
11.
J Comput Assist Tomogr ; 44(2): 255-261, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195805

RESUMO

OBJECTIVE: We aimed to determine the effects of recombinant human growth hormone (rhGH) replacement on cognitive function in subjects with poststroke cognitive impairment using resting-state functional magnetic resonance imaging. METHODS: We included 60 patients with a first-ever stroke for 3 months and a diagnosis of cognitive impairment who were randomized 1:1 to receive either rhGH subcutaneously or placebo injection for 6 months. All subjects were required to receive the same rehabilitative therapy program. Both groups were subjected to pretreatment and posttreatment neuropsychological assessment using the Montreal Cognitive Assessment, serum neurotrophic factors, biomarkers of glucose and lipid metabolism, and functional magnetic resonance imaging during 6 months of the study period. The pattern of brain activity was determined by examining the functional connectivity and amplitude of low-frequency fluctuations (ALFF) of blood oxygen level dependent signal. RESULTS: Forty-three (82.7%) completed the study. Treatment with rhGH reduced levels of triglycerides and low-density lipoprotein cholesterol but did not significantly altered plasma concentrations of glucose and glycated hemoglobin. We found a significant increase in serum insulin-like growth factor 1 levels (32.6%; P < 0.001) in the rhGH-treated group compared with that in the controls. After 6 months of rhGH treatment, mean Montreal Cognitive Assessment score improved from 16.31 (5.32) to 21.19 (6.54) (P < 0.001). The rhGH group showed significant increased area of activation with increased ALFF values in the regions of the frontal lobe, putamen, temporal lobe, and thalamus (P < 0.05), relative to the baseline conditions. The correlation analysis revealed that the ALFF and functional connectivity of default mode network was positively correlated with the ΔMoCA score and ΔIGF-1 levels; that is, the more the scale score increased, the higher the functional connection strength. No undesirable adverse effects were observed. CONCLUSIONS: The rhGH replacement has a significant impact on global and domain cognitive functions in poststroke cognitive impairment.


Assuntos
Disfunção Cognitiva/complicações , Disfunção Cognitiva/tratamento farmacológico , Hormônio do Crescimento Humano/uso terapêutico , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Resultado do Tratamento
12.
ACS Appl Mater Interfaces ; 11(40): 36469-36475, 2019 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-31544453

RESUMO

The development of low cost, portable, and disposable biosensors for equipment-free and naked-eye biosensing is in eager demand for their widespread application in biomedical field, but it is still a challenge. Herein, we propose a novel paper analytical device (PAD) for truly equipment-free and naked-eye biosensing using dopamine as the chromogenic agent based on target-initiated catalyzed oxidation reaction. The dopamine-functionalized PAD (DPAD) possesses a significant three-dimensional net structure, excellent hydrophilicity, and unique response toward G-quadruplex DNAs against other DNAs, benefiting the bio/chemo reaction occurrence to assay target biomolecules. In light of the exceptional properties, the fabricated DPAD was applied in the analysis of Dam MTase through target-triggered exponential isothermal amplification. The recognition and methylation of H1 by Dam MTase contribute to formation of abundant hemin/G-quadruplexes, which catalyze oxidation of dopamine into dopachrome and reduce the dopamine amount on the DPAD surface. In comparison with the case in which Dam MTase is absent, an evident deep pink signal originating from dopachrome is observed directly by the naked eye and relied on Dam MTase concentrations. Therefore, truly equipment-free and naked-eye detection of Dam MTase is achieved with a detection limit of 1.46 U/mL. The fabricated DPAD not only achieves Dam MTase-visualized detection but also permits the accurate determination of other analytes by varying recognizable DNA's sequences, thus offering a universal biosensor and depicting significant potential for widespread applications in biomedical field.


Assuntos
Técnicas Biossensoriais/instrumentação , Técnicas Biossensoriais/métodos , Dopamina/análise , Papel , Catálise , Quadruplex G , Metiltransferases/metabolismo , Oxirredução
13.
J Mater Chem B ; 7(36): 5461-5464, 2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31490496

RESUMO

A cellulose paper-based biosensor was developed for the equipment-free and naked-eye detection of a transcription factor (TF) using dopamine as the signal-responsive material based on exonuclease III-assisted cycling amplification. Compared with other TF biosensors, the proposed biosensor demonstrates low-cost, portable, disposable, and naked-eye detection features.


Assuntos
Técnicas Biossensoriais , Celulose/química , Dopamina/química , Papel , Fatores de Transcrição/análise , Humanos , Tamanho da Partícula , Propriedades de Superfície
14.
Biosens Bioelectron ; 137: 82-87, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31082648

RESUMO

Surface plasmon resonance (SPR) biosensing strategies have drawn substantial attention due to their advantages of label free, real time, and high performance, but complicated modification procedures and strict reaction conditions of amplification tags associated with current SPR biosensors hinder their potential utilizations. Herein, an in situ prepared AgNPs-based SPR biosensor for MicroRNA (miRNA) sensitive detection was developed based on hybridization chain reaction (HCR) without the biomodification on amplification tags. The target miRNA initiated the HCR of the hairpin probes to generate long double strand DNA (dsDNA) chains that were immobilized on SPR disk. Thus, with Ag+ intercalating into dsDNA chains, large numbers of AgNPs generated after NaBH4 reduction, resulting in the significantly elevated SPR angle. Further, the SPR angle is positively proportional to target miRNA concentrations. As a result, the in situ generated AgNPs-based SPR biosensor realized exceptional let-7a detection with linear range of 0.001-0.1 pM and detection limit (LOD) of 0.35 fM, lower than that of other SPR biosensors that used modifiable amplification tags. Featured with the modification-free characteristic and excellent performance, the proposed strategy provides new way for ultrasensitive detection of miRNA, and allows to detect other biomarkers by simply verifying the target responsive substances, and thus has a great potential for health and early disease diagnosis.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas/química , MicroRNAs/isolamento & purificação , DNA/química , Ouro/química , Humanos , Limite de Detecção , MicroRNAs/química , Ressonância de Plasmônio de Superfície
15.
Eur J Radiol ; 113: 158-164, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30927942

RESUMO

BACKGROUND: Marrow fat accumulates in diabetic conditions but remains elusive. The published works on the relationships between marrow fat phenotypes and glucose homeostasis are controversial. PURPOSE: To detect the association of insulin resistance with marrow adiposity in postmenopausal women with newly diagnosed type 2 diabetes (T2D) using chemical shift-encoded water-fat MRI. METHODS: We measured vertebral proton density fat fraction (PDFF) by 3T-MRI in 75 newly diagnosed T2D and 20 nondiabetic postmenopausal women. Bone mineral density (BMD), whole body fat mass and lean mass were determined by dual-energy X-ray absorptiometry. Insulin sensitivity was estimated using the homeostasis model assessment of insulin resistance (HOMA-IR). RESULTS: Lumbar spine PDFF was higher in women with T2D (65.9 ± 6.8%) than those without diabetes (59.5 ± 6.1%, P = 0.009). There was a consistent inverse association between the vertebral PDFF and BMD. PDFF had a positive association with glycated hemoglobin and HOMA-IR but not with fasting plasma glucose and insulin. PDFF was significantly increased, and BMD was decreased in a linear trend from the lowest (<1.90) to highest (≥2.77) HOMA-IR quartile. Multivariate linear regression analyses revealed a positive association between log-transformed HOMA-IR and PDFF after adjustment for multiple covariates (ß = 0.382, P < 0.001). The positive association of HOMA-IR with PDFF remained robust when total body lean mass and fat mass, BMD was entered into the multivariate regression model, respectively (ß = 0.293 and ß = 0.251, respectively; all P <0.05). CONCLUSIONS: Elevated HOMA-IR was linked to higher marrow fat fraction in postmenopausal women with newly diagnosed T2D independently of body compositions.


Assuntos
Adiposidade/fisiologia , Doenças da Medula Óssea/patologia , Diabetes Mellitus Tipo 2/patologia , Resistência à Insulina/fisiologia , Absorciometria de Fóton/métodos , Tecido Adiposo/patologia , Composição Corporal/fisiologia , Água Corporal/fisiologia , Medula Óssea/patologia , Estudos Transversais , Feminino , Homeostase/fisiologia , Humanos , Vértebras Lombares , Imageamento por Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pós-Menopausa/fisiologia
16.
ACS Appl Mater Interfaces ; 11(18): 16958-16964, 2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-30993969

RESUMO

Photoelectrochemical (PEC) sensing techniques have attracted considerable concerns because of the intrinsic merit of complete separation between the excitation light and responsive current but still remain a great challenge for further potential application. It is assigned to the scarcity of photoactive materials with narrow band gap, good biosafety, and high photon-to-electron conversion efficiency and unfavorable processing methods for photoactive materials on indium tin oxide. Herein, we employed a perylene-based polymer (PTC-NH2) with exceptional photoelectrical properties to develop a red-light-driven PEC sensor for ultrasensitive biosensing based on its superior electrostatic intercalation efficiency in double-stranded DNA to that in single-stranded DNA, with DNA adenine methyltransferase (Dam MTase) as the model target. The prepared PTC-NH2 was characterized by Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, and PEC techniques, and the results demonstrated that PTC-NH2 rather than metal oxides/metal sulfides/C3N4/metal complexes enjoyed the prominent capacity of converting light to current. Benefiting from the unique PEC properties of PTC-NH2 and target-initiated hybridization chain reaction (HCR) signal amplification, ultrasensitive detection of Dam MTase was accessibly realized with the detection limit of 0.015 U/mL, which is lower than that of PEC, electrochemical, or fluorescent biosensors previously reported. Furthermore, the proposed PEC sensor has been also applied in screening Dam MTase activity inhibitors. Therefore, the perylene-based PEC sensor exhibits great potential in early accurate diagnosis of DNA methylation-related diseases.


Assuntos
Técnicas Biossensoriais , DNA/química , Substâncias Intercalantes/química , DNA Metiltransferases Sítio Específica (Adenina-Específica)/isolamento & purificação , DNA de Cadeia Simples/efeitos da radiação , Técnicas Eletroquímicas/métodos , Humanos , Luz , Perileno/química , DNA Metiltransferases Sítio Específica (Adenina-Específica)/química , Compostos de Estanho/química
17.
Endokrynol Pol ; 69(4)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29952410

RESUMO

INTRODUCTION: Oxytocin might be used therapeutically as an ally to rescue osteopathy resulting from diabetes. However, the in vivo effects of oxytocin on marrow adipogenesis in diabetes remain unknown. In this longitudinal study, we aimed to investigate the protective ef-fects of oxytocin on diabetes-induced marrow adiposity in rabbits using proton MR spectroscopy. MATERIAL AND METHODS: Forty-five female New Zealand rabbits were randomly divided into controls, diabetes, and diabetes treated with oxytocin (ip, 0.78 mg/kg) for six months. Marrow fat fraction (FF) was determined by proton MR spectroscopy at baseline, and at three and six months. Bone mineral density was measured by dual-energy X-ray absorptiometry. Serum biomarkers, glycolipid metabolism, and histological analysis of marrow adipocytes were determined. RESULTS: Oxytocin treatment had positive metabolic effects in diabetic rabbits, which was based on the changes in glucose metabolism, insulin sensitivity, and lipid profiles. The diabetic rabbits demonstrated dramatic marrow adiposity in a time-dependent manner; at three and six months the FF percentage changes from baseline were 10.1% and 25.8%, respectively (all P < 0.001). Moreover, oxytocin treatment significantly reversed FF values and quantitative parameters of marrow adipocyte in diabetic rabbits to levels of naive control rabbits. Oxytocin improved bone formation marker in diabetic rabbits compared to the saline group. Also, treatment of diabetic rabbits with oxytocin significantly mitigated bone deterioration when compared with the saline-treated diabetic group (all P < 0.05). CONCLUSIONS: Oxytocin appears to alleviate harmful effects of hyperglycaemia on marrow adiposity. Proton MR spectroscopy may be a valuable tool, providing complementary information on efficacy assessments.


Assuntos
Adipócitos , Medula Óssea/efeitos dos fármacos , Diferenciação Celular , Diabetes Mellitus Experimental/fisiopatologia , Ocitocina/farmacologia , Animais , Densidade Óssea , Medula Óssea/fisiologia , Feminino , Estudos Longitudinais , Espectroscopia de Prótons por Ressonância Magnética , Coelhos , Resultado do Tratamento
18.
Menopause ; 25(6): 676-682, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29360704

RESUMO

OBJECTIVE: The clinical consequences of insulin resistance and hyperinsulinemia on marrow lipid remain elusive. We aimed to explore the effects of anthropometric and biochemical measures, that is, estimates of insulin resistance, on marrow lipid accumulation in nondiabetic postmenopausal women using magnetic resonance (MR) spectroscopy. METHODS: The study participants were 91 nondiabetic postmenopausal women. Marrow fat fraction (FF) at the L3 vertebral body by single-voxel MR spectroscopy and bone mineral density (BMD) by dual-energy x-ray absorptiometry were measured. Their glucose and lipid metabolism were determined by biochemical analysis, and their insulin sensitivity was evaluated using the Homeostatic Model Assessment of Insulin Resistance (HOMA-IR). RESULTS: Adjusted for multiple covariates including age, years since menopause, body mass index, alcohol intake, tobacco use, physical activity, and serum lipid profile, the mean FF was significantly increased, and BMD at the lumbar spine, femoral neck, and total hip decreased as quartiles of HOMA-IR increased (P for trends <0.01). HOMA-IR had a positive association with FF (mean difference 0.300, P < 0.001) and a negative association with BMD at the lumbar spine (mean difference -0.182, P = 0.016), total hip (mean difference -0.219, P = 0.001), and femoral neck (mean difference -0.195, P = 0.013). The above described associations of HOMA-IR with FF, lumbar spine, and total hip BMD remained essentially unchanged; however, the association with femoral neck BMD lost significance after adjusting for the aforementioned confounders. CONCLUSION: In nondiabetic postmenopausal women, insulin resistance is correlated with marrow lipid expansion. This association persists after adjusting for the body mass index and other potential covariates, suggesting an independent effect of insulin resistance on marrow adiposity.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Medula Óssea/diagnóstico por imagem , Resistência à Insulina , Menopausa , Absorciometria de Fóton , Idoso , Antropometria , Diabetes Mellitus Tipo 2 , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Espectroscopia de Ressonância Magnética , Pessoa de Meia-Idade
19.
Sci Rep ; 4: 7204, 2014 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-25428185

RESUMO

There is a strong correlation between the surface enhanced Raman scattering (SERS) enhancement factor (EF), the excitation wavelength, and the feature properties (composition, size, geometry, and analytes). The prediction of the EF of specific substrates, crucial to the quantitative SERS detection, is however still very difficult. The present work presents smart liquid SERS substrates consisting of suspensions of Fe3O4/Au nanoparticles, which provide high spot-to-spot uniformity, reproducibility and good reversibility. The EF of these substrates can be reversibly tuned by applying an external magnetic field. The EF magnetic tuning is within 2 orders of magnitude per substrate in the range of 10(4)-10(7). The ability to reversibly adjust the SERS EF enables to reduce EF variations caused by external effects such as substrate-to-substrate differences and long-term-storage degradation. This improves the quantitative detection of analytes and might be a significant step forward in employing SERS for practical applications.

20.
Nanoscale ; 5(24): 12330-4, 2013 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-24162334

RESUMO

Silicon nanowires are important semiconductor with core/shell structure. In this work, the piezoelectric material alpha-quartz was grown in the interface of silicon nanowires by thermal treatment at 600 °C for 0.5 h. These nanowires were employed as starting materials to fabricate piezoelectric nanogenerators, which could convert kinetic energy into electrical one, exhibiting an output voltage of 36.5 V and a response current of 1.4 µA under a free-falling object of 300 g at a height of 30 cm.

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