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1.
Otolaryngol Head Neck Surg ; : 194599820904055, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32122245

RESUMO

OBJECTIVE: To describe our clinical experience with surgical treatments for sinonasal phosphaturic mesenchymal tumors diagnosed at our institution. STUDY DESIGN: Retrospective case series. SETTING: Affiliated Sixth People's Hospital, Shanghai Jiao Tong University. SUBJECTS AND METHODS: We retrospectively reviewed the medical records of 10 patients diagnosed with phosphaturic mesenchymal tumors associated with tumor-induced osteomalacia between December 2014 and October 2019. RESULTS: There were 4 men and 6 women with a disease course of 1 to 19 years. All patients exhibited hypophosphatemia and tumor-induced osteomalacia. The tumor was located in the sinonasal region, frontal bone, and temporal bone in 8 patients, 1 patient, and 1 patient, respectively. Technetium-99m octreotide scintigraphy was used for tumor localization in 4 cases. Six patients underwent endoscopic resection; the remaining 4 underwent unilateral transorbital anterior and posterior ethmoid artery ligation + endoscopic resection, endoscopic resection + skull base repair, internal carotid artery stenting + transcatheter arterial embolization + temporal bone tumor excision + adipose tissue plugging, and endoscopic resection + transfrontal craniotomy (n = 1 each). Two patients had a history of incomplete endoscopic resection. All patients achieved clinical remission and normalized biochemical indices after surgery. Only 1 patient developed recurrence and died of a brain hernia. CONCLUSIONS: A diagnosis of sinonasal phosphaturic mesenchymal tumors should be based on a combination of clinical, imaging, and pathological findings. Technetium-99m octreotide scintigraphy helps in locating the tumor. Complete surgical excision guarantees clinical remission, and preoperative transcatheter arterial embolization or feeding artery ligation may reduce intraoperative bleeding in cases of highly vascularized tumors.

2.
Chem Commun (Camb) ; 56(19): 2933-2936, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-32040106

RESUMO

We developed a novel enzyme-free amplified SERS immunoassay by combining silver nanoparticle (AgNP)-linked immunoreaction and SERS transduction for the detection of disease biomarkers. As a proof of concept, our method was successfully illustrated with the disease biomarker α-fetoprotein with the detection limit of 3.3 × 10-13 g mL-1 and a double-blind experiment consisting of tens of serum samples was performed to confirm its reliability.

3.
J Proteome Res ; 2020 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-32073269

RESUMO

Accurate identification of lipids in biological samples is a key step in lipidomics studies. Multidimensional nuclear magnetic resonance (NMR) spectroscopy is a powerful analytical tool for this purpose as it provides comprehensive structural information on lipid composition at atomic resolution. However, the interpretation of NMR spectra of complex lipid mixtures is currently hampered by limited spectral resolution and the absence of a customized lipid NMR database along with user-friendly spectral analysis tools. We introduce a new two-dimensional (2D) NMR metabolite database "COLMAR Lipids" that was specifically curated for hydrophobic metabolites presently containing 501 compounds with accurate experimental 2D 13C-1H heteronuclear single quantum coherence (HSQC) chemical shift data measured in CDCl3. A new module in the public COLMAR suite of NMR web servers was developed for the (semi)automated analysis of complex lipidomics mixtures (http://spin.ccic.osu.edu/index.php/colmarm/index2). To obtain 2D HSQC spectra with the necessary high spectral resolution along both 13C and 1H dimensions, nonuniform sampling in combination with pure shift spectroscopy was applied allowing the extraction of an abundance of unique cross-peaks belonging to hydrophobic compounds in complex lipidomics mixtures. As shown here, this information is critical for the unambiguous identification of underlying lipid molecules by means of the new COLMAR Lipids web server, also in combination with mass spectrometry, as is demonstrated for Caco-2 cell and lung tissue cell extracts.

4.
Anal Chim Acta ; 1099: 119-125, 2020 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-31986268

RESUMO

γ-Glutamyl transpeptidase (GGT) has attracted considerable attention for its regulatory effect on glutathione metabolism in living organisms; further, its close relationship with physiological dysfunctions such as hepatitis and liver cancers has enhanced its applicability. Therefore, the accurate detection of GGT levels is particularly important for the early diagnosis of diseases. Thus, we herein report the development of a surface-enhanced Raman spectroscopic (SERS) probe, namely bis-s,s'-((s)-4,4'-thiolphenylamide-Glu) (b-(s)-TPA-Glu), that comprises of a γ-glutamyl moiety for detection of the GGT activity. In this system, detection was achieved by observing differences in the SERS spectral profiles of the b-(s)-TPA-Glu probe and its corresponding hydrolysis product that resulted from the catalytic action of GGT. This SERS probe system exhibited a high selectivity toward GGT due to a combination of its specific catalytic action and the distinctive spectroscopic fingerprint of the SERS technique. The developed SERS approach was also found to be approximately linear in the range of 0.2-200 U/L, and a limit of detection of 0.09 U/L was determined. Furthermore, the proposed SERS method was suitable for detection of the GGT activity of clinical serum samples and also for evaluation of the inhibitors of GGT. Consequently, this approach is considered to be a promising diagnostic and drug screening tool for GGT-associated diseases.

5.
New Phytol ; 225(4): 1618-1634, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31574168

RESUMO

Kiwifruit (Actinidia spp.) is a climacteric fruit with high sensitivity to ethylene, influenced by multiple ethylene-responsive structural genes and transcription factors. However, the roles of other post-transcriptional regulators (e.g. miRNAs) necessary for ripening remain elusive. High-throughput sequencing sRNAome, degradome and transcriptome methods were used to identify further contributors to ripening control in the kiwifruit (A. deliciosa cv 'Hayward'). Two NAM/ATAF/CUC domain transcription factors (AdNAC6 and AdNAC7), both predicted targets for miR164, showed significant upregulation by exogenous ethylene. Gene expression analysis and luciferase reporter assays indicated that Ade-miR164 and one of its precursor miRNAs (Ade-MIR164b) were repressed by ethylene treatment and negatively correlated with AdNAC6/7 expression. Subsequent analysis indicated that both AdNAC6 and AdNAC7 proteins are transcriptional activators and physically bind the promoters of AdACS1 (1-aminocyclopropane-1-carboxylate synthase), AdACO1 (1-aminocyclopropane-1-carboxylic acid oxidase), AdMAN1 (endo-ß-mannanase) and AaTPS1 (terpene synthase). Moreover, subcellular analysis indicated that the location of the AdNAC6/7 proteins was influenced by Ade-miR164. Multiple omics-based approaches revealed a novel regulatory link for fruit ripening that involved ethylene-miR164-NAC. The regulatory pathway for miR164-NAC is present in various fruit (e.g. Rosaceae fruit, citrus, grape), with implications for fruit ripening regulation.

6.
J Chem Theory Comput ; 16(2): 1311-1318, 2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-31877033

RESUMO

Molecular dynamics (MD) simulations provide a unique atomic-level description of the structure and dynamics of proteins, which is essential for the mechanistic understanding of protein interactions and function in living organisms. However, traditional MD force fields that are optimized for folded proteins often generate overly compact structures and incorrect characteristics of intrinsically disordered proteins (IDPs) and protein regions (IDRs), thereby limiting the quantitative insights that can be gained from MD simulations. We introduce the residue-specific protein force field, ff99SBnmr2, which is derived from ff99SBnmr1 by balancing the backbone dihedral angle potentials in a residue-specific manner to quantitatively reproduce dihedral angle distributions from an experimental coil library. The new force field substantially improves the backbone conformational ensembles of disordered proteins, protein regions, and peptides while keeping well-defined protein structures stable and accurate. This balanced new force field should enable a myriad of applications that require quantitative descriptions of IDPs, IDRs, loop dynamics, and folding/unfolding equilibria in the presence and absence of interaction partners.


Assuntos
Aminoácidos , Dipeptídeos/química , Simulação de Dinâmica Molecular , Dobramento de Proteína , Técnicas Eletroquímicas , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Conformação Proteica
7.
Methods Mol Biol ; 2050: 175-179, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31468492

RESUMO

Electroporation refers to the application of high strength electric pulse to create transient pores in the membrane, thereby enabling the passage of hydrophilic molecules into the cells. Based on the properties of cell and cell wall, the electroporation parameters vary among the algal species. Here, we demonstrated the optimized protocol for successful introduction of recombinant DNA (~5000 bp) into Nannochloropsis oceanica. The linearized recombinant plasmid that harbors eGFP and Bh-sle as the reporter and marker gene, respectively, was electroporated into the electrocompetent N. oceanica cells at voltage of 2200 V, 50 µF, resistance at 600 Ω using electroporator, and the transformed cells were then screened by molecular analysis. The report exemplifies a straightforward and reliable electroporation strategy for generating transgenic N. oceanica cells.

8.
ACS Sens ; 4(12): 3234-3239, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31736302

RESUMO

A functional surface-enhanced Raman scattering (SERS) nanosensor which can simultaneously detect nitric oxide (NO) and peroxynitrite (ONOO-) in living cells is explored. The SERS nanosensor is fabricated through modifying gold nanoparticles (AuNPs) with newly synthesized 3,4-diaminophenylboronic acid pinacol ester (DAPBAP), which has two reactive groups. The simultaneous detection achieved in this work is not only because of the SERS spectral changes of the nanosensor resulting from the dual reactivity of DAPBAP on AuNPs with NO and ONOO- but also by the narrow SERS bands suitable for multiplex detection. Owing to the combination of SERS fingerprinting information and chemical reaction specificity, the nanosensor has great selectivity for NO and ONOO-, respectively. In addition, the nanosensor has a wide linearity range from 0 to 1.0 × 10-4 M with a submicromolar sensitivity. More importantly, simultaneous monitoring of NO and ONOO- in the Raw264.7 cells has been fulfilled by this functional nanosensor, which shows that the SERS strategy will be promising in comprehension of the physiological issues related with NO and ONOO-.

9.
Anal Chem ; 91(24): 15686-15693, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31718151

RESUMO

Knowledge of the chemical identity of metabolite molecules is critical for the understanding of the complex biological systems to which they belong. Since metabolite identities and their concentrations are often directly linked to the phenotype, such information can be used to map biochemical pathways and understand their role in health and disease. A very large number of metabolites however are still unknown; i.e., their spectroscopic signatures do not match those in existing databases, suggesting unknown molecule identification is both imperative and challenging. Although metabolites are structurally highly diverse, the majority shares a rather limited number of structural motifs, which are defined by sets of 1H and 13C chemical shifts of the same spin system. This allows one to characterize unknown metabolites by a divide-and-conquer strategy that identifies their structural motifs first. Here, we present the structural motif-based approach "SUMMIT Motif" for the de novo identification of unknown molecular structures in complex mixtures, without the need for extensive purification, using NMR in tandem with two newly curated NMR molecular structural motif metabolomics databases (MSMMDBs). For the identification of structural motif(s), first, the 1H and 13C chemical shifts of all the individual spin systems are extracted from 2D and 3D NMR spectra of the complex mixture. Next, the molecular structural motifs are identified by querying these chemical shifts against the new MSMMDBs. One database, COLMAR MSMMDB, was derived from experimental NMR chemical shifts of known metabolites taken from the COLMAR metabolomics database, while the other MSMMDB, pNMR MSMMDB, is based on predicted chemical shifts of metabolites of several existing large metabolomics databases. For molecules consisting of multiple spin systems, spin systems are connected via long-range scalar J-couplings. When this motif-based identification method was applied to the hydrophilic extract of mouse bile fluid, two unknown metabolites could be successfully identified. This approach is both accurate and efficient for the identification of unknown metabolites and hence enables the discovery of new biochemical processes and potential biomarkers.

10.
Biomed Environ Sci ; 32(8): 592-601, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31488235

RESUMO

OBJECTIVE: To investigate the development and characterizations of the hepatocytes isolated from fetal ovine and to determine the effect of hypoxia on their growth and metabolism. METHODS: Fresh hepatocytes were isolated from the liver of fetal ovine at late gestation, cultured in specific media, and exposed to normoxia (21% O2) or hypoxia (2% O2). The cellular characteristics and population purity were identified by immunocytochemistry and flow cytometry (FCM). The effects of hypoxia on cell cycle and apoptosis of the hepatocytes were evaluated by FCM, whereas the cellular ultrastructure changes were examined with a transmission electron microscope. RESULTS: The cell purity of hepatocytes was over 95%. Under hypoxia exposure, the hepatocytes showed a gradual increase in proportion at the S phase and in proliferative index, followed with a compatible increase in apoptosis and progressively decreased cell viability. Additionally, the organelles of the hepatocytes demonstrated dramatic changes, including swelling of mitochondria, disorder in cristae arrangement, expansion of endoplasmic reticulum, and a large number of circular lipid droplets emerging in the cytoplasm. CONCLUSION: Fetal ovine hepatocytes could be primarily cultured in a short-term culture system with a high purity of over 95% and with their preserved original characteristics. Hypoxia could induce changes in ultrastructural and inhibit the proliferation of cultured fetal ovine hepatocytes through apoptotic mechanisms.


Assuntos
Feto/fisiologia , Hepatócitos/fisiologia , Oxigênio/análise , Ovinos/fisiologia , Anaerobiose , Animais , Técnicas de Cultura de Células
11.
ACS Omega ; 4(4): 7543-7549, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-31459847

RESUMO

The exploration of simultaneous removal of co-existing or multiple pollutants from water by the means of nanomaterials paves a new avenue that is free from secondary pollution and inexpensive. In the aquatic environment, river water contains a mixture of ions, which can influence the adsorption process. In this respect, removing heavy metal ions becomes a true challenge. Here, four heavy metal ions, namely, Pb2+, Cd2+, Cu2+, and Ni2+, have been successfully removed simultaneously from river water using ultrafine mesoporous magnetite (Fe3O4) nanoparticles (UFMNPs) based on the affinity of these metal ions toward the UFMNP surfaces as well as their unique mesoporous structure, promoting the easy adsorption. The individual removal efficiencies of Pb2+, Cd2+, Cu2+, and Ni2+ ions from river water were 98, 87, 90, and 78%, respectively, whereas the removal efficiencies of the mixed Pb2+, Cd2+, Cu2+, and Ni2+ ions were 86, 80, 84, and 54%, respectively, in the same river water. Thus, the data clearly indicate the complex removal of heavy metal ions in multi-ion systems. This study has demonstrated the huge potential of UFMNPs to be effective for their use in wastewater treatment, especially to simultaneously remove multiple heavy metal ions from aqueous media.

12.
Mol Med Rep ; 20(2): 1915-1924, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31257527

RESUMO

Kidney­type glutaminase (GLS1) plays a significant role in tumor metabolism. Our recent studies demonstrated that GLS1 was aberrantly expressed in hepatocellular carcinoma (HCC) and facilitated tumor progression. However, the roles of GLS1 in intrahepatic cholangiocarcinoma (ICC) remain largely unknown. Thus, the aim of this study was to evaluate the expression and clinical significance of GLS1 in ICC. For this purpose, combined data from the Oncomine database with those of immunohistochemistry were used to determine the expression levels of GLS1 in cancerous and non­cancerous tissues. Second, a wound­healing assay and Transwell assay were used to observe the effects of the knockdown and overexpression of GLS1 on the invasion and migration of ICC cells. We examined the associations between the expression of GLS1 and epithelial­mesenchymal transition (EMT)­related markers by western blot analysis. Finally, we examined the associations between GLS1 levels and clinicopathological factors or patient prognosis. The results revealed that GLS1 was overexpressed in different digestive system tumors, including ICC, and that GLS1 expression in ICC tissue was higher than that in peritumoral tissue. The overexpression of GLS1 in RBE cells induced metastasis and invasion. Moreover, the EMT­related markers, E­cadherin and Vimentin, were regulated by GLS1 in ICC cells. By contrast, the knockdown of GLS1 expression in QBC939 cells yielded opposite results. Clinically, a high expression of GLS1 in ICC samples negatively correlated with E­cadherin expression and positively correlated with Vimentin expression. GLS1 protein expression was associated with tumor differentiation (P=0.001) and lymphatic metastasis (P=0.029). Importantly, patients with a high GLS1 expression had a poorer overall survival (OS) and a shorter time to recurrence than patients with a low GLS1 expression. Multivariate analysis indicated that GLS1 expression was an independent prognostic indicator. On the whole, the findings of this study demonstrated that GLS1 is an independent prognostic biomarker of ICC. GLS1 facilitates ICC progression and may thus prove to be a therapeutic target in ICC.


Assuntos
Biomarcadores Tumorais/genética , Colangiocarcinoma/genética , Glutaminase/genética , Recidiva Local de Neoplasia/genética , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Colangiocarcinoma/patologia , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Prognóstico , Vimentina/genética
13.
J Hazard Mater ; 379: 120823, 2019 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-31276918

RESUMO

A three-dimensional (3D) substrate was developed by assembling a monolayer of graphitic carbon nitride (O-g-C3N4) on Ag nanorod arrays (Ag NRs) for sensitive and recyclable surface enhanced Raman scattering (SERS) detection. The prepared Ag NRs/O-g-C3N4 substrate not only generated a significant Raman enhancement effect as a result of the strong π-π stacking interaction between O-g-C3N4 and the analytes but also possessed excellent self-cleaning property via visible-light irradiation that was attributed to its outstanding catalytic performance. Highly sensitive SERS detection could be achieved with a LOD of 8.2 × 10-10 M for R6 G, and the substrate could be used repeatedly for at least four cycles with tolerable intensity attenuation. In addition, the 3D substrate exhibited long-term stability originating from the electron-donor effect of O-g-C3N4 and high reproducibility due to the uniform decoration of O-g-C3N4 on the Ag NRs through the strong interaction. Furthermore, using Ag NRs/O-g-C3N4, the recyclable detection of antibiotics in a water sample was demonstrated with high sensitivity, which indicates that the 3D Ag NRs/O-g-C3N4 substrate is a promising candidate for eliminating the challenges of single-use SERS substrates and building a portable SERS platform to sense organic molecular species.

14.
Biotechnol Bioeng ; 116(11): 3006-3015, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31282986

RESUMO

There has been growing interest in using microalgae as production hosts for a wide range of value-added compounds. However, microalgal genetic improvement is impeded by lack of genetic tools to concurrently control multiple genes. Here, we identified two novel strong promoters, designated Pt202 and Pt667, and delineated their potential role on simultaneously driving the expression of key lipogenic genes in Phaeodactylum tricornutum. In silico analyses of the identified promoter sequences predicted the presence of essential core cis elements such as TATA and CAAT boxes. Regulatory role of the promoters was preliminarily assessed by using GUS reporter which demonstrated strong GUS expression. Thereafter, two key lipogenic genes including malic enzyme (PtME) and 5-desaturase (PtD5b), were overexpressed by the two promoters Pt202 and Pt667, respectively, in P. tricornutum. Combinatorial gene overexpression did not impair general physiological performance, meanwhile neutral lipid content was remarkably increased by 2.4-fold. GC-MS analysis of fatty acid methyl esters revealed that eicosapentaenoic acid (EPA; C20:5) was increased significantly. The findings augment a crucial kit to microalgal genetic tools that could facilitate the multiple-gene expression driven by various promoters, and promote microalgae for industrial bioproduction.

15.
Biomed Res Int ; 2019: 5696801, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31179330

RESUMO

This study aimed at clarifying the mechanism and role of survivin in hypoxia-induced multidrug resistance (MDR) of laryngeal carcinoma cells. Human laryngeal cancer cells were incubated under hypoxia or normoxia. The expression of survivin was silenced by performing RNA interference. Additionally, by Western blot and real-time quantitative RT-PCR, survivin expression was detected. The sensitivity of human laryngeal carcinoma cells to multiple drugs was measured by CCK-8 assay. Meanwhile, the apoptosis of cells induced by cisplatin or paclitaxel was assessed by Annexin-V/propidium iodide staining analysis. Under hypoxic conditions, the upregulation of survivin was abolished by RNA interference. Then, CCK-8 analysis demonstrated that the sensitivity to multiple agents of laryngeal carcinoma cells could be increased by inhibiting survivin expression (P < 0.05). Moreover, Annexin-V/propidium iodide staining analysis revealed that decreased expression of survivin could evidently increase the apoptosis rate of laryngeal carcinoma cells that were induced by cisplatin or paclitaxel evidently (P < 0.05). Our data suggests that hypoxia-elicited survivin may exert a pivotal role in regulating hypoxia-induced MDR of laryngeal cancer cells by preventing the apoptosis of cells induced by chemotherapeutic drug. Thus, blocking survivin expression in human laryngeal carcinoma cells may provide an avenue for gene therapy.


Assuntos
Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Hipóxia , Neoplasias Laríngeas/tratamento farmacológico , Survivina/metabolismo , Survivina/farmacologia , Anexina A5/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Expressão Gênica , Humanos , Paclitaxel/farmacologia , Interferência de RNA , Survivina/genética , Regulação para Cima
16.
Neural Regen Res ; 14(10): 1814-1822, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31169200

RESUMO

Accumulating studies suggest that neuroinflammation characterized by microglial overactivation plays a pivotal role in the pathogenesis of Parkinson's disease. As such, inhibition of microglial overactivation might be a promising treatment strategy to delay the onset or slow the progression of Parkinson's disease. Ginsenoside Rb1, the most active ingredient of ginseng, reportedly exerts neuroprotective effects by suppressing inflammation in vitro. The present study aimed to evaluate the neuroprotective and anti-inflammatory effects of ginsenoside Rb1 in a lipopolysaccharide-induced rat Parkinson's disease model. Rats were divided into four groups. In the control group, sham-operated rats were intraperitoneally administered normal saline for 14 consecutive days. In the ginsenoside Rb1 group, ginsenoside Rb1 (20 mg/kg) was intraperitoneally injected for 14 consecutive days after sham surgery. In the lipopolysaccharide group, a single dose of lipopolysaccharide was unilaterally microinjected into the rat substantial nigra to establish the Parkinson's disease model. Lipopolysaccharide-injected rats were treated with normal saline for 14 consecutive days. In the ginsenoside Rb1 + lipopolysaccharide group, lipopolysaccharide was unilaterally microinjected into the rat substantial nigra. Subsequently, ginsenoside Rb1 was intraperitoneally injected for 14 consecutive days. To investigate the therapeutic effects of ginsenoside Rb1, behavioral tests were performed on day 15 after lipopolysaccharide injection. We found that ginsenoside Rb1 treatment remarkably reduced apomorphine-induced rotations in lipopolysaccharide-treated rats compared with the lipopolysaccharide group. To investigate the neurotoxicity of lipopolysaccharide and potential protective effect of ginsenoside Rb1, contents of dopamine and its metabolites in the striatum were measured by high-performance liquid chromatography. Compared with the lipopolysaccharide group, ginsenoside Rb1 obviously attenuated the lipopolysaccharide-induced depletion of dopamine and its metabolites in the striatum. To further explore the neuroprotective effect of ginsenoside Rb1 against lipopolysaccharide-induced neurotoxicity, immunohistochemistry and western blot assay of tyrosine hydroxylase were performed to evaluate dopaminergic neuron degeneration in the substantial nigra par compacta. The results showed that lipopolysaccharide injection caused a large loss of tyrosine hydroxylase-immunoreactive neurons in the substantia nigra and a significant decrease in overall tyrosine hydroxylase expression. However, ginsenoside Rb1 noticeably reversed these changes. To investigate whether the neuroprotective effect of ginsenoside Rb1 was associated with inhibition of lipopolysaccharide-induced microglial activation, we examined expression of the microglia marker Iba-1. Our results confirmed that lipopolysaccharide injection induced a significant increase in Iba-1 expression in the substantia nigra; however, ginsenoside Rb1 effectively suppressed lipopolysaccharide-induced microglial overactivation. To elucidate the inhibitory mechanism of ginsenoside Rb1, we examined expression levels of inflammatory mediators (tumor necrosis factor-α, interleukin-1ß, inducible nitric oxide synthase, and cyclooxygenase 2) and phosphorylation of nuclear factor kappa B signaling-related proteins (IκB, IKK) in the substantia nigra with enzyme-linked immunosorbent and western blot assays. Our results revealed that compared with the control group, phosphorylation and expression of inflammatory mediators IκB and IKK in the substantia nigra of lipopolysaccharide group rats were significantly increased; whereas, ginsenoside Rb1 obviously reduced lipopolysaccharide-induced changes on the lesioned side of the substantial nigra par compacta. These findings confirm that ginsenoside Rb1 can inhibit inflammation induced by lipopolysaccharide injection into the substantia nigra and protect dopaminergic neurons, which may be related to its inhibition of the nuclear factor kappa B signaling pathway. This study was approved by the Experimental Animal Ethics Committee of Shandong University of China in April 2016 (approval No. KYLL-2016-0148).

17.
Food Sci Biotechnol ; 28(2): 319-327, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30956843

RESUMO

This study aims at examining the level of biogenic amines (BAs) in different kinds of sufu commonly consumed in China. The correlation between different BAs and physical and chemical index in sufu samples was also investigated. The results proved that different processing technologies altered the distribution of BAs in commercial sufu. Total BA level was significantly correlated with salt content and pH. Some of the sufu samples in this survey contained higher levels of BAs, of which 26.6% of the samples might induce histamine poisoning, 15.6% might induce headache in virtue of phenylethylamine, and 23.4% might cause migraine and headache in virtue of tyramine. Moreover, 6.3% of the sufu samples with total BA content over 1000 mg/kg may be harmful to human health. From the food safety perspective, some sufu should not be excessively consumed daily and should be processed under strict sanitary conditions to decrease the BA level.

18.
Anal Chem ; 91(10): 6507-6513, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-30916930

RESUMO

Tyrosinase (TYR) which can catalyze the oxidation of catechol is recognized as a significant biomarker of melanocytic lesions, thus developing powerful methods for the determination of TYR activity is highly desirable for the early diagnosis of melanin-related diseases, including melanoma. Herein, we develop a novel portable and recyclable surface-enhanced Raman scattering (SERS) sensor, prepared by assembling gold nanoparticles and p-thiol catechol ( p-TC) on an ITO electrode, for detecting TYR activity via the SERS spectral variation caused by the conversion of p-TC into its corresponding quinone under TYR catalysis. The developed SERS sensor has a rapid response to TYR within 1 min under the optimized conditions and shows high selectivity for TYR with the detection limit at 0.07 U/mL. Importantly, this SERS sensor can be easily regulated by applying negative voltage to achieve circular utilization, favoring the automation of SERS detection. Furthermore, the presented recyclable SERS sensor can perform well on both the determination of TYR activity in serum and the assessment of TYR inhibitor, demonstrating huge potential in the sensitive, selective, and facile detection of TYR activity for disease diagnosis and drug screening related with TYR.

19.
Talanta ; 198: 527-533, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30876595

RESUMO

Assay technologies capable of detecting biomarker concentrations in unprocessed whole blood samples are fundamental for applications in medical diagnostics. SERS nano-tags integrated magnetic-separation biosensor (MSB) was realized for the first time for immunoassay in whole blood. The reliability and sensitivity of this method rely, in a large extent, on the quality and properties of the SERS nano-tags. The constructed silicacoated Ag SERS nano-tags as labels were used in a rapid and specific MSB immune sensor to detect Matrix Metalloproteinases 9 (MMP-9) in unprocessed blood samples. With fast screening ability and outstanding sensitivity, we anticipate that this method would greatly promote practical application of stroke-based early-stage cancer diagnosis.


Assuntos
Imunoensaio , Metaloproteinase 9 da Matriz/sangue , Humanos , Campos Magnéticos , Nanopartículas Metálicas/química , Prata/química , Análise Espectral Raman/instrumentação , Propriedades de Superfície
20.
Sci Adv ; 5(1): eaau3795, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30729156

RESUMO

Commercialization of algal lipids and biofuels is still impractical owing to the unavailability of lipogenic strains and lack of economically viable oil extraction strategies. Because lipogenesis is governed by multiple factors, success in generating industrial-suitable algal strains using conventional strategies has been limited. We report the discovery of a novel bZIP1 transcription factor, NobZIP1, whose overexpression results in a remarkable elevation of lipid accumulation and lipid secretion in a model microalga Nannochloropsis oceanica, without impairing other physiological properties. Chromatin immunoprecipitation-quantitative PCR analysis revealed that the key genes up- and down-regulated by NobZIP1 are involved in lipogenesis and cell wall polymer synthesis, respectively, which, in turn, induce lipid overproduction and secretion. Among these regulated genes, UDP-glucose dehydrogenase was shown to alter cell wall composition, thus also boosting lipid secretion. In summary, these results offer a comprehensive strategy for concurrent lipid overproduction and secretion, strongly increasing the commercial potential of microalgae.

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