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1.
Biomaterials ; 241: 119910, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32135354

RESUMO

Sulfur dioxide (SO2) with the largest quantity and widest distribution in the atmosphere is closely related to many nervous system diseases via mitochondria respiration. It is of great significance to monitor this gaseous molecule during various physiological and pathological processes, but currently the task still remains challenging due to the lack of reliable tools. Through-bond energy transfer (TBET) is a relatively new strategy to fabricate ratiometric fluorescent probes, which does not need spectral overlap between the energy donor and acceptor while provides high energy-transfer efficiency. It offers strong dual fluorescence emission peaks as well as large wavelength differences between the two peaks, which increases the bioimaging resolution and reliability. Herein, we developed a TBET-based ratiometric probe (TBET-SO2) with a series of superior properties for in vivo SO2 imaging. Excited by near-infrared pulsed laser (810 nm), the probe undergoes TBET and produces far-red emission (611 nm). It achieved significant energy-transfer efficiency (90.5%) and large spectral gap between two peaks (△λ = 118 nm). Upon reacting with SO2, TBET-SO2 showed ~30-fold enhancement of ratiometric signal contributed by the baseline resolved emissions. A detection limit of as low as 0.09 µM was obtained. Furthermore, TBET-SO2 was successfully applied for visualizing the mitochondrial SO2 in living cells and mice brain tissue during the neuroinflammation process induced by SO2 pollution.

2.
Int J Mol Sci ; 21(3)2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32028614

RESUMO

The BRI1-EMS suppressor 1 (BES1)/brassinazole-resistant 1 (BZR1) transcription factors, key components in the brassinosteroid signaling pathway, play pivotal roles in plant growth and development. However, the function of BES1/BZR1 in crops during stress response remains poorly understood. In the present study, we characterized ZmBES1/BZR1-5 from maize, which was localized to the nucleus and was responsive to abscisic acid (ABA), salt and drought stresses. Heterologous expression of ZmBES1/BZR1-5 in transgenic Arabidopsis resulted in decreased ABA sensitivity, facilitated shoot growth and root development, and enhanced salt and drought tolerance with lower malondialdehyde (MDA) content and relative electrolyte leakage (REL) under osmotic stress. The RNA sequencing (RNA-seq) analysis revealed that 84 common differentially expressed genes (DEGs) were regulated by ZmBES1/BZR1-5 in transgenic Arabidopsis. Subsequently, gene ontology and KEGG pathway enrichment analyses showed that the DEGs were enriched in response to stress, secondary metabolism and metabolic pathways. Furthermore, 30 DEGs were assigned to stress response and possessed 2-15 E-box elements in their promoters, which could be potentially recognized and bound by ZmBES1/BZR1-5. Taken together, our results reveal that the ZmBES1/BZR1-5 transcription factor positively regulates salt and drought tolerance by binding to E-box to induce the expression of downstream stress-related genes. Therefore, our study contributes to the better understanding of BES1/BZR1 function in the stress response of plants.

3.
Chem Commun (Camb) ; 56(7): 1050-1053, 2020 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-31868186

RESUMO

It has been speculated that both the intracellular viscosity and H2O2 level in Alzheimer's disease (AD) brains are higher than that in healthy brains, but direct evidence from living beings is scarce. Herein, we report a NIR emissive fluorescent probe with a large Stokes shift for the associated detection of mitochondrial viscosity and H2O2 in live rat brains with AD for the first time.


Assuntos
Doença de Alzheimer/metabolismo , Corantes Fluorescentes/química , Peróxido de Hidrogênio/análise , Mitocôndrias/metabolismo , Compostos de Quinolínio/química , Precursor de Proteína beta-Amiloide/genética , Animais , Corantes Fluorescentes/efeitos da radiação , Corantes Fluorescentes/toxicidade , Células HeLa , Humanos , Luz , Masculino , Camundongos Endogâmicos BALB C , Camundongos Transgênicos , Mitocôndrias/química , Imagem Óptica/métodos , Presenilina-1/genética , Compostos de Quinolínio/efeitos da radiação , Compostos de Quinolínio/toxicidade , Viscosidade
4.
Head Neck ; 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31872505

RESUMO

BACKGROUND: This study tries to find the patterns of new nodules in contralateral thyroid lobe among papillary thyroid carcinomas (PTCs) after lobectomy using ultrasonography. METHODS: Of note, 456 PTCs were enrolled. Clinicopathological features of primary tumors and sonographic patterns of new nodules in contralateral lobe were documented. Logistic regression analysis was performed to identify risk factors for new nodules. RESULTS: The overall incidence of new nodules was 41.9%. 96.3% of new nodules were no greater than 1 cm while only 10.5% of those were with high suspicion of malignancy. There was no difference in the incidence and sonographic patterns of new nodules between patients with an original tumor size <1 cm (n = 267) vs 1 to 4 cm (n = 189). Multivariate logistic regression analysis showed age (OR, 1.021; 95% CI, 1.001-1.041; P = .036) played risk factor for new nodules while tumor size >1 cm did not. CONCLUSION: New nodules in the contralateral lobe were common, but usually small and benign by ultrasound features. Older age was found to be a risk factor to predict new nodules. This study supports lobectomy for 1-4 cm PTC in terms of incidence of new nodules on the remnant lobe.

5.
Anal Chem ; 91(24): 15757-15762, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31724390

RESUMO

The detection of hydroxyl radical (·OH) in vivo faces challenges as ·OH has short lifetime and low concentration in the body. Fluorescence imaging within the second near-infrared window (NIR-II, 1000-1700 nm) is a promising approach to in vivo organ and tissue imaging, but ·OH fluorescent probes emitting at this region have not been reported up to now because of the difficulty of probe design. Herein, we report the strategy to fabricate the first NIR-II probe for ·OH by directly breaking/recovering the conjugated system and rigid planar structure of an organic fluorophore, which could regulate the fluorescence intensity regardless of emission wavelength. This activable probe, Hydro-1080, emitted in 1000-1400 nm after responding to ·OH. Hydro-1080 exhibited excellent sensitivity (LOD = 0.5 nM) and selectivity to ·OH. It was able to track subtle variation of [·OH] in liver induced by external stimuli and offered clear images with high contrast. This work also indicates that this simple and straightforward strategy can be extended to develop NIR-II fluorescent probes efficiently.

6.
Chem Commun (Camb) ; 55(49): 7037-7040, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31143887

RESUMO

A π-extended red absorbing Se-rhodamine (Se-NR) was synthesised and characterized. By masking the amine of Se-NR as an azide, we successfully constructed a bio-orthogonally activatable photosensitizer (Se-NR-Az). Se-NR-Az was not photocytotoxic, but when activated by the Staudinger reaction, photocytotoxicity was restored.


Assuntos
Azidas/farmacologia , Fotoquimioterapia , Fármacos Fotossensibilizantes/farmacologia , Rodaminas/farmacologia , Selênio/farmacologia , Azidas/química , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células HeLa , Humanos , Estrutura Molecular , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/química , Rodaminas/química , Selênio/química , Relação Estrutura-Atividade
7.
Abdom Radiol (NY) ; 44(1): 310-317, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30088050

RESUMO

PURPOSE: To evaluate the utility of real-time contrast-enhanced ultrasound (CEUS)-guided coaxial needle biopsies for focal liver lesions (FLL) that were inconspicuous or could not be accurately identified the active site on B-mode ultrasound (US). MATERIALS AND METHODS: This prospective study included 76 patients who had CEUS-guided coaxial needle biopsies for FLL between December 2015 and June 2017. We recorded characteristics of target lesions. We evaluated conspicuity of target lesions and accuracy of identifying the active site of target lesions on B-mode US and CEUS using a 5-point scale. Patients were divided into three groups, and analyzed according to body mass index (BMI). Based on the final diagnosis, the diagnostic performance was evaluated. RESULTS: The mean size and depth of target lesions were 41.5 ± 28.5 and 47.9 ± 18.9 mm on CEUS, respectively. In arterial phase, the enhanced pattern of target lesions varied. The conspicuity of target lesions and accuracy of identifying the active site of target lesions was significantly improved on CEUS compared to B-mode US (p < 0.05). The three BMI groups had significant differences in conspicuity of target lesions after using CEUS (p < 0.05). The high BMI group had a greater change in conspicuity of lesions compared to the normal BMI group or the low BMI group (p < 0.05). The sensitivity, specificity, and accuracy of this technique for the diagnosis of FLL were 92.8%, 100%, and 93.4%, respectively. CONCLUSION: Real-time CEUS-guided coaxial needle biopsy can be very useful for FLL that are inconspicuous or cannot be accurately identified the active site on B-mode US.


Assuntos
Meios de Contraste , Aumento da Imagem/métodos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Ultrassonografia de Intervenção/métodos , Adulto , Idoso , Biópsia por Agulha , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Talanta ; 167: 134-142, 2017 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-28340703

RESUMO

Hydrogen sulfide (H2S) is a kind of gaseous signalling molecule that plays pivotal role in various biological processes. So far, it is still a challenge to develop convenient and reliable methods for H2S detection in lysosomes. Herein, we developed a novel ratiometric two-photon fluorescent probe LR-H2S for imaging H2S in lysosomes. Upon the addition of H2S (using Na2S as a donor) to LR-H2S in buffer solution, the azide group is reduced to amino group and subsequently the carbamate ester is cleaved by 1,6-elimination, resulting in a fluorescence emission increase at 541nm and a concomitant emission decrease at 475nm. Under two-photon excitation of 840nm, an 80-fold fluorescence ratio (F541/F475) enhancement was observed with a wide linear range of 25-2500µM. The detection limit was calculated to be 0.70µM based on 3σ/k method, indicating that the probe can detect H2S with a high sensitivity. The probe also shows excellent selectivity toward H2S among other biological interference species and features with low cytotoxicity and favorable two-photon properties. Furthermore, LR-H2S can easily localize in lysosomes and vividly illuminate endogenous/exogenous H2S level and distribution in lysosomes of living SGC-7901 cells.


Assuntos
Corantes Fluorescentes/metabolismo , Sulfeto de Hidrogênio/metabolismo , Lisossomos/metabolismo , Imagem Molecular/métodos , Fótons , Linhagem Celular Tumoral , Sobrevivência Celular , Humanos
9.
Chem Sci ; 7(8): 5230-5235, 2016 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30155173

RESUMO

As a pivotal signalling molecule involved in various physiological and pathological processes, nitric oxide (NO) has motivated increasing interest in the last few decades. Although a considerable number of fluorescent probes have been developed for NO imaging, the in situ tracking of this gas molecule in biological events remains a big challenge, mainly because of the relatively short excitation and/or emission wavelengths, which are subject to background interference and lowered collection efficiency in deep-tissue imaging. Herein, we report a far-red emissive (650 nm) two-photon (TP) excitable NRNO probe, using Nile Red as the TP fluorophore, for NO detection and imaging both in vitro and in vivo. The NRNO probe shows a fast (within 180 s) and specific fluorescence response toward NO with a limit of detection (LOD) as low as 46 nM. The excellent properties of NRNO enable it to sensitively detect both exogenously and endogenously generated NO in living cells. The "NIR in" and "far-red out" lights lead to improved penetrating ability, thus endowing the probe with high resolution for the illumination of deep tissues. It is therefore able to visualize the NO generation in a lipopolysaccharide (LPS)-mediated inflammation process for the first time. Our results demonstrate that NRNO could be a practical tool for studying the NO-related biological events. Moreover, this study also suggests the possibility of using Nile Red and its derivatives to develop far-red emissive TP probes, which is an important, yet undeveloped area.

10.
Zhen Ci Yan Jiu ; 34(3): 175-9, 2009 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-19761111

RESUMO

OBJECTIVE: To study the underlying mechanism of electroacupuncture (EA) in relieving depression. METHODS: A total of 30 Wistar rats were randomly divided into normal control group (n=10), model group (n=10) and EA group (n=10). Depression model was established by lonely raising and chronic unpredictable mild stress for 21 days. EA (2 Hz, 1 mA) was applied to "Baihui" (GV 20) and "Sanyinjiao" (SP 6) for 20 min, once daily for 14 days. The expression (option density) of hippocampal somatostatin (SS) and SS mRNA was detected by using immunohistochemistry and reversed transcription-polymerase chain reaction (RT-PCR) techniques respectively. RESULTS: Compared to normal control group, the crossing movement and rearing movement times of open-field test, and sucrose consumption in model group decreased significantly (P < 0.01), and hippocampal SS and SS mRNA expressions were downregulated remarkably (P < 0.05). Compared to model group, the crossing movement and rearing movement times in EA group increased considerably (P < 0.01), and hippocampal SS and SS mRNA expressions were upregulated remarkably (P < 0.05). No significant difference was found between EA and normal control groups in SS and SS mRNA expression. CONCLUSION: EA can effectively improve depression rats' behavior activity and upregulate hippocampal SS and SS mRNA expression.


Assuntos
Depressão/terapia , Eletroacupuntura , Hipocampo/metabolismo , Somatostatina/genética , Somatostatina/metabolismo , Estresse Psicológico/complicações , Animais , Doença Crônica , Depressão/etiologia , Depressão/genética , Depressão/metabolismo , Modelos Animais de Doenças , Expressão Gênica , Humanos , Masculino , Distribuição Aleatória , Ratos , Ratos Wistar
11.
Zhen Ci Yan Jiu ; 34(2): 89-92, 119, 2009 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-19685720

RESUMO

OBJECTIVE: To study the effect of electroacupuncture (EA) on liver cytochrome P450 1 A 1 immunoactivity, superoxide dismutase (SOD) and malondialdehyde (MDA) contents in nonalcoholic fatty liver disease (NAFLD) rats. METHODS: Thirty male SD rats were randomized into normal control (n = 10), model (n = 10) and EA (n = 10) groups. NAFLD model was established by feeding the animal with high-fat forage for 8 weeks. EA (1.6-2 Hz, 1-4 mA) was applied to bilateral "Zusanli" (ST 36), "Fenglong" (ST 40), "Sanyinjiao" (SP 6) and "Taichong" (LR 3) for 15 min, once daily for 4 weeks. Then the rats anesthetized with ether were killed for collecting liver tissue. Following homogenate and centrifugalization of the partial liver tissue, the supernatant was collected for assaying superoxide dismutase (SOD) and malondialdehyde (MDA) contents by xanthinoxidase chromometry and thio-malonylurea chromometry respectively. The other partial liver tissue samples were fixed in 10% formalin, followed by paraffin imbedding and sectioning (4 microm), and staining with streptavidin-perosidase methods respectively for displaying hepatic pathological changes and cytochrom P450 1 A 1 immunoreaction. RESULTS: Compared with control group, hepatic SOD content of model group was significantly lower (P < 0.05), and MDA level and cytochrome P450 1 A 1 (CYP 1 A 1) integrated optic density (IOD) value were obviously higher in model group (P < 0.05). In comparison with model group, liver SOD level of EA group increased considerably (P < 0.05), while MDA level and CYP 1 A 1 IOD of EA group decreased evidently in EA group (P < 0.05). CONCLUSION: EA can effectively reduce lipid peroxidation and up-regulate CYP 1 A 1 expression in nonalcoholic fatty liver tissue, which may contribute to its effect in improving fatty liver.


Assuntos
Citocromo P-450 CYP1A1/análise , Eletroacupuntura , Fígado Gorduroso/terapia , Peroxidação de Lipídeos , Fígado/enzimologia , Animais , Fígado Gorduroso/metabolismo , Masculino , Malondialdeído/análise , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo
12.
Zhen Ci Yan Jiu ; 33(2): 111-5, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18630587

RESUMO

OBJECTIVE: To investigate the mechanism of electroacupuncture (EA) in treating nonalcoholic fatty liver disease (NAFLD) in rats. METHODS: Thirty male SD rats were randomized into normal control, NAFLD model and EA groups, with 10 cases in each. NAFLD model was established by feeding the rats with high-fat food for 8 weeks. EA (2 Hz, 4 mA) was applied to "Zusanli" (ST 36), "Fenglong" (ST 40), "Sanyinjiao" (SP 6), and "Taichong" (LR 3) for 15 min, once daily for 4 weeks. Fasting blood sugar (FBG) and serum free fatty acids (FFA) were detected with chromatometry; serum insulin (INS) was determined with radioimmunoassay; homeostasis model assessment insulin resistance (HOMA-IR) and liver index (LI) were calculated. Liver tissue was cut into sections for detecting pathological changes. RESULTS: Compared with normal control group, FBG, INS, FFA, HOMA-IR and LI of model group increased significantly (P<0.05), and hepatic diffuse steatosis with cellular necrosis and inflammatory cell infiltration was obvious. In comparison with model group, all the 5 indexes in EA group decreased significantly (P<0.05), and pathological changes as hepatic steatosis, etc. were significantly reduced. CONCLUSION: EA may be used to effectively improve NAFLD by lowering insulin resistance.


Assuntos
Eletroacupuntura , Fígado Gorduroso/terapia , Resistência à Insulina , Animais , Ácidos Graxos não Esterificados/sangue , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado/patologia , Masculino , Medicina Tradicional Chinesa , Ratos , Ratos Sprague-Dawley
13.
Zhen Ci Yan Jiu ; 33(2): 116-9, 2008 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-18630588

RESUMO

OBJECTIVE: To observe the effect of electroacupuncture( EA) on synovia superoxide dismutase (SOD) activity, malondialdehyde (MDA) and nitric oxide (NO) contents in rabbits with knee osteoarthritis (KOA). METHODS: A total of 40 New Zealand rabbits were randomly divided into control, model, massage and EA groups, with 10 cases in each. KOA model was established by gypusum fixing method. EA (1.6-2 Hz, 1-2 mA) was applied to left "Yanglingquan" (GB 34), "Xuehai" (SP 10), "Zusanli" (ST 36) and "Liangqiu" (ST 34) for 25 min, once daily for 21 days. For massage group, the affected knee joint was pressed, kneaded, stretched and rotated repeatedly for 15 min every time, followed by forced running about 100 m. The intra-joint synovia was collected (0.4-0.6 ml) for detecting contents of SOD with xanthine oxidase method, MDA with thiobarbituric acid method and NO with nitrate reductase method. RESULTS: Compared with control group, synovia SOD activity in model group decreased considerably (P<0.05), while MDA and NO contents increased significantly (P<0.05). After 3 weeks' treatment, compared with pre-treatment and model group, synovia SOD activity increased markedly (P<0.05), and MDA and NO contents lowered remarkably in both EA and massage groups (P<0.05). No significant differences were found between EA and massage groups in these 3 indexes (P>0.05). CONCLUSION: Both EA and massage can raise synovia SOD activity and lower MDA and NO content, which may contribute to their effect in relieving knee osteoarthritis in the rabbit.


Assuntos
Eletroacupuntura , Osteoartrite do Joelho/terapia , Líquido Sinovial/metabolismo , Animais , Feminino , Radicais Livres , Articulação do Joelho/patologia , Masculino , Malondialdeído/análise , Óxido Nítrico/fisiologia , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/patologia , Coelhos , Superóxido Dismutase/metabolismo
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