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1.
Nano Lett ; 24(1): 245-253, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38157424

RESUMO

Mechanically strong and damage-tolerant corrosion protection layers are of great technological importance. However, corrosion protection layers with high modulus (>1.5 GPa) and tensile strength (>100 MPa) are rare. Here, we report that a 130 µm thick densified wood veneer with a Young's modulus of 34.49 GPa and tensile strength of 693 MPa exhibits both low diffusivity for metal ions and the ability of self-recovery from mechanical damage. Densified wood veneer is employed as an intermediate layer to render a mechanically strong corrosion protection structure, referred to as "wood corrosion protection structure", or WCPS. The corrosion rate of low-carbon steel protected by WCPS is reduced by 2 orders of magnitude than state-of-the-art corrosion protection layers during a salt spray test. The introduction of engineered wood veneer as a thin and mechanically strong material points to new directions of sustainable corrosion protection design.

2.
Pharmacol Res ; 191: 106776, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37084858

RESUMO

The paucity of medications with novel mechanisms for pain treatment combined with the severe adverse effects of opioid analgesics has led to an imperative pursuit of non-opioid analgesia and a better understanding of pain mechanisms. Here, we identify the putative glutamatergic inputs from the paraventricular thalamic nucleus to the nucleus accumbens (PVTGlut→NAc) as a novel neural circuit for pain sensation and non-opioid analgesia. Our in vivo fiber photometry and in vitro electrophysiology experiments found that PVTGlut→NAc neuronal activity increased in response to acute thermal/mechanical stimuli and persistent inflammatory pain. Direct optogenetic activation of these neurons in the PVT or their terminals in the NAc induced pain-like behaviors. Conversely, inhibition of PVTGlut→NAc neurons or their NAc terminals exhibited a potent analgesic effect in both naïve and pathological pain mice, which could not be prevented by pretreatment of naloxone, an opioid receptor antagonist. Anterograde trans-synaptic optogenetic experiments consistently demonstrated that the PVTGlut→NAc circuit bi-directionally modulates pain behaviors. Furthermore, circuit-specific molecular profiling and pharmacological studies revealed dopamine receptor 3 as a candidate target for pain modulation and non-opioid analgesic development. Taken together, these findings provide a previously unknown neural circuit for pain sensation and non-opioid analgesia and a valuable molecular target for developing future safer medication.


Assuntos
Analgesia , Analgésicos não Narcóticos , Camundongos , Animais , Núcleos da Linha Média do Tálamo , Núcleo Accumbens/fisiologia , Dor/tratamento farmacológico
3.
World J Urol ; 41(12): 3611-3618, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37898576

RESUMO

PURPOSE: Culture-negative urine specimens can be rapidly screened by urine flow cytometry (UFC), while low positive predictive value (PPV) limits the clinical application. We explored the factors associated with a low PPV. METHODS: A total of 5095 urine specimens were analyzed with UFC and culture. Diagnostic performance of leukocytes, bacteria, and BACT-info flags was evaluated by sensitivity, specificity, PPV, and negative predictive value (NPV). The association of contaminated culture and squamous epithelial cell count and BACT-info flag was performed by logistic regression analysis. RESULTS: The NPVs of parallel combination of bacteria and leucocytes were 98.9% in males and 97.9% in females, and PPVs of serial combination were 86.6% and 77.8% in men and women, respectively. The PPV of Gram-negative flag was higher than that of Gram-positive flag. The proportions of contamination in the urine culture results of false positive specimens were 86.9% in males and 98.5% in females at the cutoff points of the serial combination, and these parameters were 53.2% in males and 85.6% in females for the Gram-positive flag. There was a statistically significant association between contaminated cultures and squamous epithelial cells count in females, but not in males. Associations between contaminated cultures and Gram-positive flags or Gram-pos/-neg flags were statistically significant, but there was no association between contaminated cultures and Gram-negative flags. CONCLUSIONS: A serial combination of leukocytes and bacteria may maximize PPV in the diagnosis of bacterial urinary tract infection by urine flow cytometry, and contamination is the main reason for a low PPV.


Assuntos
Infecções Bacterianas , Infecções Urinárias , Masculino , Humanos , Feminino , Valor Preditivo dos Testes , Citometria de Fluxo/métodos , Infecções Urinárias/microbiologia , Urinálise/métodos , Bactérias , Sensibilidade e Especificidade , Urina/microbiologia
4.
Br J Anaesth ; 130(4): 446-458, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36737387

RESUMO

BACKGROUND: Corticotropin-releasing factor (CRF) neurones in the paraventricular nucleus (PVN) of the hypothalamus (PVNCRF neurones) can promote wakefulness and are activated under anaesthesia. However, whether these neurones contribute to anaesthetic effects is unknown. METHODS: With a combination of chemogenetic and molecular approaches, we examined the roles of PVNCRF neurones in isoflurane anaesthesia in mice and further explored the underlying cellular and molecular mechanisms. RESULTS: PVN neurones exhibited increased Fos expression during isoflurane anaesthesia (mean [standard deviation], 218 [69.3] vs 21.3 [7.3]; P<0.001), and ∼75% were PVNCRF neurones. Chemogenetic inhibition of PVNCRF neurones facilitated emergence from isoflurane anaesthesia (11.7 [1.1] vs 13.9 [1.2] min; P=0.001), whereas chemogenetic activation of these neurones delayed emergence from isoflurane anaesthesia (16.9 [1.2] vs 13.9 [1.3] min; P=0.002). Isoflurane exposure increased CRF protein expression in PVN (4.0 [0.1] vs 2.2 [0.3], respectively; P<0.001). Knockdown of CRF in PVNCRF neurones mimicked the effects of chemogenetic inhibition of PVNCRF neurones in facilitating emergence (9.6 [1.1] vs 13.0 [1.4] min; P=0.003) and also abolished the effects of chemogenetic activation of PVNCRF neurones on delaying emergence from isoflurane anaesthesia (10.3 [1.3] vs 16.0 [2.6] min; P<0.001). Acute, but not chronic, stress delayed emergence from isoflurane anaesthesia (15.5 [1.5] vs 13.0 [1.4] min; P=0.004). This effect was reversed by chemogenetic inhibition of PVNCRF neurones (11.7 [1.6] vs 14.7 [1.4] min; P=0.001) or knockdown of CRF in PVNCRF neurones (12.3 [1.5] vs 15.3 [1.6] min; P=0.002). CONCLUSIONS: CRF neurones in the PVN of the hypothalamus neurones modulate isoflurane anaesthesia and acute stress effects on anaesthesia through CRF signalling.


Assuntos
Anestesia , Isoflurano , Camundongos , Animais , Hormônio Liberador da Corticotropina/metabolismo , Hormônio Liberador da Corticotropina/farmacologia , Núcleo Hipotalâmico Paraventricular/metabolismo , Isoflurano/farmacologia , Hipotálamo/metabolismo
5.
Acta Pharmacol Sin ; 44(5): 1095-1104, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36418428

RESUMO

CKLF (chemokine-like factor)-MARVEL transmembrane domain containing protein 6 (CMTM6) is a novel regulator to maintain the stability of PD-L1. CMTM6 can colocalize and interact with PD-L1 on the recycling endosomes and cell membrane, preventing PD-L1 from lysosome-mediated degradation and proteasome-mediated degradation thus increasing the half-life of PD-L1 on the cell membrane. The difficulties in obtaining stable full-length PD-L1 and CMTM6 proteins hinder the research on their structures, function as well as related drug development. Using lauryl maltose neopentyl glycol (LMNG) as the optimized detergent and a cell membrane mimetic strategy, we assembled a stable membrane-bound full-length CMTM6-PD-L1 complex with amphipol A8-35. When the PD-1/PD-L1-CMTM6 interactions were analyzed, we found that CMTM6 greatly enhanced the binding and delayed the dissociation of PD-1/PD-L1, thus affecting immunosuppressive signaling and anti-apoptotic signaling. We then used the CMTM6-PD-L1 complex as immunogens to generate immune repertoires in camels, and identified a functional anti-CMTM6 nanobody, called 1A5. We demonstrated that the anti-CMTM6 nanobody greatly decreased T-cell immunosuppression and promoted apoptotic susceptibility of tumor cells in vitro, and mainly relied on the cytotoxic effect of CD8+ T-cells to exert tumor growth inhibitory effects in CT26 tumor-bearing mice. In conclusion, the stable membrane-bound full-length CMTM6-PD-L1 complex has been successfully used in studying PD-1/PD-L1-CMTM6 interactions and CMTM6-targeting drug development, suggesting CMTM6 as a novel tumor immunotherapy target.


Assuntos
Antígeno B7-H1 , Proteínas com Domínio MARVEL , Neoplasias , Anticorpos de Domínio Único , Animais , Camundongos , Antígeno B7-H1/metabolismo , Linfócitos T CD8-Positivos/metabolismo , Neoplasias/imunologia , Neoplasias/terapia , Receptor de Morte Celular Programada 1/metabolismo , Proteínas com Domínio MARVEL/imunologia , Proteínas com Domínio MARVEL/metabolismo , Engenharia de Proteínas/métodos , Anticorpos de Domínio Único/biossíntese
6.
Eur J Nucl Med Mol Imaging ; 49(6): 1810-1821, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35013776

RESUMO

PURPOSE: Overexpression of epithelial cell adhesion molecule (EpCAM) plays essential roles in tumorigenesis and tumor progression in almost all epithelium-derived cancer. Monitoring EpCAM expression in tumors can be used for the diagnosis, staging, and prognosis of cancer patients, as well as guiding the individualized treatment of EpCAM-targeted drugs. In this study, we described the synthesis and evaluation of a site-specifically [99mTc]Tc-labeled EpCAM-targeted nanobody for the SPECT/CT imaging of EpCAM expression. METHODS: We first prepared the [99mTc]Tc-HYNIC-G4K; then, it was site-specifically connected to EpCAM-targeted nanobody NB4. The in vitro characteristics of [99mTc]Tc-NB4 were investigated in HT-29 (EpCAM positive) and HL-60 (EpCAM negative) cells, while the in vivo studies were performed using small-animal SPECT/CT in the subcutaneous tumor models and the lymph node metastasis model to verify the specific targeting capacity as well as the potential applications of [99mTc]Tc-NB4. RESULTS: [99mTc]Tc-NB4 displayed a high EpCAM specificity both in vitro and in vivo. SPECT/CT imaging revealed that [99mTc]Tc-NB4 was cleared rapidly from the blood and normal organs except for the kidneys, and HT-29 tumors were clearly visualized in contrast with HL-60 tumors. The uptake value of [99mTc]Tc-NB4 in HT-29 tumors was increased continuously from 3.77 ± 0.39%ID/g at 0.5 h to 5.53 ± 0.82%ID/g at 12 h after injection. Moreover, the [99mTc]Tc-NB4 SPECT/CT could clearly image tumor-draining lymph nodes. CONCLUSION: [99mTc]Tc-NB4 is a broad-spectrum, specific, and sensitive SPECT radiotracer for the noninvasive imaging of EpCAM expression in the epithelium-derived cancer and revealed a great potential for the clinical translation.


Assuntos
Neoplasias , Tomografia Computadorizada de Emissão de Fóton Único , Animais , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Humanos , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Tecnécio , Tomografia Computadorizada de Emissão de Fóton Único/métodos
7.
Sensors (Basel) ; 22(14)2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35890891

RESUMO

The millimeter wave (mmWave) channel is dominated by line-of-sight propagation. Therefore, the acquisition of angle-of-arrival (AoA) and polarization state of the wave is of great significance to the receiver. In this paper, we investigate AoA and polarization estimation in a mmWave system employing dual-polarized antenna arrays. We propose an enhanced AoA estimation method using a localized hybrid dual-polarized array for a polarized mmWave signal. The use of dual-polarized arrays greatly improves the calibration of differential signals and the signal-to-noise ratio (SNR) of the phase offset estimation between adjacent subarrays. Given the estimated phase offset, an initial AoA estimate can be obtained, and is then used to update the phase offset estimation. This leads to a recursive estimation with improved accuracy. We further propose an enhanced polarization estimation method, which uses the power of total received signals at dual-polarized antennas to compute the cross-correlation-to-power ratio instead of using only one axis dipole. Thus the accuracy of polarization parameter estimation is improved. We also derive a closed-form expression for mean square error lower bounds of AoA estimation and present an average SNR analysis for polarization estimation performance. Simulation results demonstrate the superiority of the enhanced AoA and polarization parameter estimation methods compared to the state of the art.

8.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35409244

RESUMO

Sugars, which are critical osmotic compounds and signalling molecules in plants, and Sugars Will Eventually be Exported Transporters (SWEETs), which constitute a novel family of sugar transporters, play central roles in plant responses to multiple abiotic stresses. In the present study, a member of the SWEET gene family from cucumber (Cucumis sativus L.), CsSWEET2, was identified and characterized. Histochemical analysis of ß-glucuronidase expression in transgenic Arabidopsis plants showed that CsSWEET2 is highly expressed in the leaves; subcellular localization indicated that CsSWEET2 proteins are localized in the plasma membrane and endoplasmic reticulum. Heterologous expression assays in yeast demonstrated that CsSWEET2 encodes an energy-independent hexose/H+ uniporter that can complement both glucose and fructose transport deficiencies. Compared with wild-type Arabidopsis plants, transgenic Arabidopsis plants overexpressing CsSWEET2 had much lower relative electrolyte leakage levels and were much more resistant to cold stress. Sugar content analysis showed that glucose and fructose levels in the transgenic Arabidopsis plants were significantly higher than those in the wild-type plants. Taken together, our results suggest that, by mediating sugar metabolism and compartmentation, CsSWEET2 plays a vital role in improving plant cold tolerance.


Assuntos
Arabidopsis , Cucumis sativus , Arabidopsis/genética , Arabidopsis/metabolismo , Resposta ao Choque Frio , Cucumis sativus/metabolismo , Frutose/metabolismo , Regulação da Expressão Gênica de Plantas , Glucose/metabolismo , Hexoses/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética
9.
J Environ Manage ; 319: 115652, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35820309

RESUMO

In this study, a universal method that combined fixed-point monitoring and numerical simulation was used to understand the source, fate and risks of antibiotics in environment. Results showed that the antibiotic concentration in vegetables, soil and manure from 53 fixed-point monitoring sampling sites were ND-18.47, ND-1438.50 and ND-24710.00 µg kg-1, respectively. There were positive correlations between the antibiotic concentrations of vegetables and soil as well as between soil and manure. The average Amountsoil/manure values were 1.48-46.02, indicating that antibiotics built up pseudo persistent residues in soil due to repeated fertilization. The modified level-III fugacity model showed that tetracyclines and fluoroquinolones tend to remain in soil given their sorption and mobility, while sulfonamides were highly distributed in plants, especially in leaves. Norfloxacin, ofloxacin, sulfadiazine, sulfamethoxazole and sulfisoxazole were found to be risk factors in facility agriculture and should be continuously monitored during agricultural production. Most importantly, we used the inversion method to determine the recommended maximum residue limits of antibiotics in soil. This will not only allow for better control of the amount of the antibiotics in the environment, but also act as a potential method to assess the risks of pollutants without maximum residue limits in the environment.


Assuntos
Poluentes do Solo , Solo , Agricultura , Antibacterianos/análise , Monitoramento Ambiental/métodos , Esterco/análise , Solo/química , Poluentes do Solo/análise , Verduras
10.
Molecules ; 27(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35011461

RESUMO

Glucosinolates (GSLs) are important precursor compounds with anticancer activities in Brassicaceae vegetables and are readily hydrolyzed by myrosinase. Given the diversity of these species, establishing an accurate and universal method to quantify intact GSLs in different plant tissues is necessary. Here, we compared and optimized three tissue disruption methods for sample preparation. After microwave treatment for 90 s, 13 GSLs in homogenized Chinese cabbage samples were recovered at 73-124%. However, a limitation of this method was that different tissues could not be processed under the same microwave conditions. Regarding universality, GSLs in Brassicaceae vegetables could be extracted from freeze-dried sample powder with 70% methanol (v/v) or frozen-fresh sample powder with 80% methanol (v/v). Moreover, heating extraction is necessary for GSLs extracted from frozen-fresh sample powder. Average recoveries of the two optimized methods were 74-119% with relative standard deviations ≤ 15%, with the limits of quantification 5.72-17.40 nmol/g dry weight and 0.80-1.43 nmol/g fresh weight, respectively. Notably, the method for analyzing intact GSLs was more efficient than that for desulfo-GSLs regarding operational complexity, detection speed and quantification accuracy. The developed method was applied to identify the characteristic GSLs in 15 Brassicaceae vegetables, providing a foundation for further research on GSLs.


Assuntos
Brassicaceae/química , Cromatografia Líquida de Alta Pressão , Análise de Alimentos , Glucosinolatos/análise , Glucosinolatos/química , Espectrometria de Massas em Tandem , Verduras/química , Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Reprodutibilidade dos Testes
11.
Acta Pharmacol Sin ; 41(3): 348-357, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31506573

RESUMO

Intestinal mucositis is a common side effect of anticancer regimens that exerts a negative impact on chemotherapy. Superoxide dismutase (SOD) is a potential therapy for mucositis but efficient product is not available because the enzyme is degraded following oral administration or induces an immune reaction after intravascular infusion. Multi-modified Stable Anti-Oxidant Enzymes® (MS-AOE®) is a new recombinant SOD with better resistance to pepsin and trypsin. We referred it as MS-SOD to distinguish from other SODs. In this study we investigated its potential to alleviate 5-FU-induced intestinal injury and the mechanisms. An intestinal mucositis model was established in C57/BL6 mice by 5-day administration of 5-FU (50 mg/kg every day, ip). MS-SOD (800 IU/10 g, ig) was given once daily for 9 days. 5-FU caused severe mucositis with intestinal morphological damage, bodyweight loss and diarrhea; MS-SOD significantly decreased the severity. 5-FU markedly increased reactive oxygen species (ROS) and inflammatory cytokines in the intestine which were ameliorated by MS-SOD. Furthermore, MS-SOD modified intestinal microbes, particularly reduced Verrucomicrobia, compared with the 5-FU group. In Caco2 cells, MS-SOD (250-1000 U/mL) dose-dependently decreased tBHP-induced ROS generation. In RAW264.7 cells, MS-SOD (500 U/mL) had no effect on LPS-induced inflammatory cytokines, but inhibited iNOS expression. These results demonstrate that MS-SOD can scavenge ROS at the initial stage of injury, thus play an indirect role in anti-inflammatory and barrier protein protection. In conclusion, MS-SOD attenuates 5-FU-induced intestinal mucositis by suppressing oxidative stress and inflammation, and influencing microbes. MS-SOD may exert beneficial effect in prevention of intestinal mucositis during chemotherapy in clinic.


Assuntos
Fluoruracila/efeitos adversos , Mucosa Intestinal/metabolismo , Superóxido Dismutase/metabolismo , Administração Oral , Animais , Fluoruracila/administração & dosagem , Fluoruracila/metabolismo , Injeções Intraperitoneais , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/metabolismo , Superóxido Dismutase/administração & dosagem
12.
Plant Cell Rep ; 38(6): 731-739, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30903268

RESUMO

KEY MESSAGE: OsIAAGLU could catalyze the reaction of IAA with glucose to generate IAA-glucose. Overexpression of OsIAAGLU in rice resulted in altered rice shoot architecture and root gravitropism. The distribution and levels of indole-3-acetic acid (IAA) within plant tissues are well known to play vital roles in plant growth and development. An important mechanism of regulating free IAA levels in monocots is formation of IAA ester conjugates. In this study, a cytosol-localized protein encoded by the rice gene of indole-3-acetic acid glucosyltransferase (OsIAAGLU) was found to catalyze the reaction of free IAA with glucose to generate IAA-glucose. Expression of OsIAAGLU could be induced by IAA and NAA. The number of tillers and leaf angle was significantly increased with a concomitant decrease in plant height and panicle length in the transgenic rice lines overexpressing OsIAAGLU compared to the wild-type (WT) plants. Phenotypes of iaaglu mutants constructed using the CRISPR/Cas9 system had no obvious differences with WT plants. Furthermore, overexpression of OsIAAGLU resulted in reduced sensitivity to IAA/NAA and altered gravitropic response of the roots in the transgenic plants. Free IAA contents in the leaves, root tips, and lamina joint of OsIAAGLU-overexpressing transgenic lines were lower than those of WT plants. These results support that OsIAAGLU could play a regulatory role in IAA homeostasis and rice architecture.


Assuntos
Glucose/química , Glucose/farmacologia , Ácidos Indolacéticos/química , Ácidos Indolacéticos/farmacologia , Oryza/efeitos dos fármacos , Oryza/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Regulação da Expressão Gênica de Plantas/genética , Oryza/genética , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/genética , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética
13.
Small ; 14(47): e1802372, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30307695

RESUMO

Precision medicine has made a significant breakthrough in the past decade. The most representative success is the molecular targeting therapy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKI) in non-small-cell lung cancer (NSCLC) with oncogenic drivers, approved by the US Food and Drug Administration (FDA) as first-line therapeutics for substituting chemotherapy. However, the rapidly developed TKI resistance invariably leads to unsustainable treatment. For example, gefitinib is the first choice for advanced NSCLC with EGFR mutation, but most patients would soon develop secondary EGFRT790M mutation and acquire gefitinib resistance. TKI resistance is a severe emergency issue to be solved in NSCLC, but there are a few investigations of nanomedicine reported to address this pressing problem. To overcome EGFRT790M -associated drug resistance, a novel delivery and therapeutic strategy is developed. A PD-L1 nanobody is identified, and first used as a targeting ligand for liposomal codelivery. It is found that simvastatin/gefitinib combination nanomedicine can remodel the tumor microenvironment (e.g., neovascularization regulation, M2-macrophage repolarization, and innate immunity), and display the effectiveness of reversing the gefitinib resistance and enhancing the EGFRT790M -mutated NSCLC treatment outcomes. The novel simvastatin-based nanomedicine provides a clinically translatable strategy for tackling the major problem in NSCLC treatment and demonstrates the promise of an old drug for new application.


Assuntos
Antígeno B7-H1/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Neovascularização Patológica/metabolismo , Anticorpos de Domínio Único/imunologia , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Resistencia a Medicamentos Antineoplásicos/genética , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/uso terapêutico , Receptores ErbB/genética , Gefitinibe/administração & dosagem , Gefitinibe/uso terapêutico , Humanos , Mutação , Nanomedicina/métodos , Neovascularização Patológica/tratamento farmacológico , Sinvastatina/administração & dosagem , Sinvastatina/uso terapêutico , Anticorpos de Domínio Único/metabolismo
14.
Bioconjug Chem ; 29(5): 1703-1713, 2018 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-29617563

RESUMO

This work reported a new method of design for the immobilization of acetylcholinesterase (AChE) based on its molecular structure to improve its sensitivity and stability. The immobilization binding site on the surface of AChE was determined using MOLCAD's multi-channel functionality. Then, 11 molecules ((+)-catechin, (-)-epicatechin, (-)-gallocatechin, hesperetin, naringenin, quercetin, taxifolin, (-)-epicatechin gallate, flupirtine, atropine, and hyoscyamine) were selected from the ZINC database (about 50 000 molecules) as candidate affinity ligands for AChE. The fluorescence results showed that the binding constant Kb between AChE and the ligands ranged from 0.01344 × 104 to 4.689 × 104 M-1 and there was one independent class of binding site for the ligands on AChE. The AChE-ligand binding free energy ranged from -12.14 to -26.65 kJ mol-1. Naringenin, hesperetin, and quercetin were the three most potent immobilized affinity ligands. In addition, it was confirmed that the binding between the immobilized ligands only occurred at a single site, located in an inactive area on the surface of AChE, and did not affect the enzymatic activity as shown through a competition experiment and enzyme assay. This method based on protein surface structural recognition with high sensitivity and stability can be used as a generic approach for design of the enzyme immobilization and biosensor development.


Assuntos
Acetilcolinesterase/química , Enzimas Imobilizadas/química , Acetilcolinesterase/metabolismo , Aminopiridinas/química , Aminopiridinas/farmacologia , Sítios de Ligação , Antagonistas Colinérgicos/química , Antagonistas Colinérgicos/farmacologia , Descoberta de Drogas , Enzimas Imobilizadas/metabolismo , Flavonoides/química , Flavonoides/farmacologia , Humanos , Cinética , Ligantes , Modelos Moleculares , Ligação Proteica
15.
J Sep Sci ; 41(3): 713-722, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29134768

RESUMO

A modified quick, easy, cheap, effective, rugged, and safe method was established for simultaneous extraction and cleanup of multiple antibiotics in leafy vegetables, and ultra-high performance liquid chromatography with tandem mass spectrometry was used for analysis. Antibiotics in leafy vegetables were extracted with citric acid/sodium citrate in mixed solvents consisting of acetonitrile/methanol (85:15, v/v) from 10 g of vegetables. Octadecylsilyl and graphitized carbon black were used as dispersant adsorbents. This method was able to effectively extract all of the target antibiotics from leafy vegetables. The average recoveries of 20 antibiotics ranged from 57 to 91%. The limits of detection were 0.33-2.92 µg/kg. The developed method subsequently demonstrated its selectivity, sensitivity, and reliability for detecting multiple antibiotics in 15 samples. Antibiotic residues in vegetables have attracted great concern with respect to human health. It is recommended that standards should be established for antibiotic residues in vegetables to ensure food safety.


Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão , Resíduos de Drogas/análise , Extração em Fase Sólida , Espectrometria de Massas em Tandem , Verduras/química , Adsorção , Limite de Detecção , Metanol , Folhas de Planta/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes
16.
Ecotoxicol Environ Saf ; 159: 120-126, 2018 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-29734067

RESUMO

This study investigated the occurrence and sources of polycyclic aromatic hydrocarbons (PAHs) from arable soils in Beijing and compared them with 4 other types of soils: soil from uncultivated land, an incineration plant, a suburb and a woodland. The total concentrations of PAHs ranged from 189.3 to 888.7 µg/kg (mean: 518.2 µg/kg for greenhouses and 455.2 µg/kg for fields). The seven carcinogenic PAHs accounted for 11.2-81.3% of Σ15PAHs in arable soils. Benzo[a]pyrene toxic equivalent (BaPeq) concentrations were 82.8 µg/kg and 85.4 µg/kg in greenhouses and fields, respectively. Greenhouses and fields were both dominated by PAHs with 3 and 4 rings. Acenaphthene (ACE), indeno[1,2,3-cd] pyrene (IcdP) and benzo[ghi]perylene (BghiP) were the major compounds. These results showed that there was insignificant difference between the soil from greenhouses and fields and both had low carcinogenic potential risk. The diagnostic ratios suggested that the arable soils were mainly contaminated by coal/biomass combustion. Based on a positive matrix factorization (PMF) model, six sources were identified including coal combustion, waste incineration, tar, diesel combustion, biomass burning and gasoline combustion. Coal and gasoline combustion contributed over 40% of the measured PAHs in arable soils. Diesel combustion, tar and waste incineration were the main sources of pollution for soil from the uncultivated land, woodland and incineration plant/suburban. It was concluded that PMF was effective in determining the source apportionment. Urbanization and the evolution of human activities have caused PAH sources to become more complicated in industrial areas compared to regions with little human disturbance. Because of this, various factors need to be considered to control the PAH contamination in arable soils.


Assuntos
Carcinógenos/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Pequim , Biomassa , Carvão Mineral , Monitoramento Ambiental , Gasolina , Atividades Humanas , Incineração , Urbanização
17.
Mediators Inflamm ; 2017: 7659023, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28250578

RESUMO

Obesity has been associated with osteoarthritis (OA) due to increased mass and metabolic factors which are independent of the biomechanical contribution to joint load. Resveratrol, a natural polyphenolic compound, exerts protective effects on OA through its anti-inflammatory property. However, the mechanism of resveratrol on obesity-related OA is unclear. To investigate the effect and possible mechanism of oral resveratrol on obesity-related OA, we fed C57BL/6J mice with a high-fat diet (HFD) for 16 weeks to establish obesity-related OA model; then two doses (22.5 mg/kg and 45 mg/kg) of resveratrol were given by gavage for additional 12 weeks. Mice with HFD significantly increased body weights compared to the control mice, while resveratrol treatment did not cause obvious weight loss. Histological assessments showed that resveratrol at 45 mg/kg significantly improved OA symptoms. Levels of serum IL-1ß and leptin were decreased by resveratrol treatment and positively correlated with Mankin scores. Moreover, resveratrol significantly inhibited the expression of TLR4 and TRAF6 in cartilage. These results suggest that HFD induced obesity can lead to the occurrence of OA, and resveratrol may alleviate OA pathology by decreasing the levels of systematic inflammation and/or inhibiting TLR4 signaling pathway in cartilage. Thus, resveratrol might be a promising therapeutic treatment for obesity-related OA.


Assuntos
Osteoartrite/tratamento farmacológico , Estilbenos/uso terapêutico , Administração Oral , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/uso terapêutico , Western Blotting , Dieta Hiperlipídica/efeitos adversos , Ensaio de Imunoadsorção Enzimática , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Osteoartrite/metabolismo , Resveratrol , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais/efeitos dos fármacos , Estilbenos/administração & dosagem
18.
Appl Microbiol Biotechnol ; 99(2): 919-28, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25557628

RESUMO

A novel multiplex detection array based on Luminex xMAP technology was developed and validated for simultaneous detection of five major viruses causing swine reproductive diseases. By combining one-step asymmetric multiplex reverse transcription polymerase chain reaction (RT-PCR) with xMAP bead-based hybridization and flow cytometry analysis, the resulting multiplex assay was capable of detecting single and mixed infections of PRRSV, PCV-2, PRV, CSFV, and PPV in a single reaction. The assay accurately detected and differentiated 23 viral strains used in this study. The low detection limit was determined as 2.2-22 copies/µL (corresponding to 0.5-6.8 fg/µL DNA template) on plasmid constructs containing viral fragments. The intra-assay and inter-assay variances (CV%) were low that ranged from 2.5 to 5.4 % and 4.1 to 7.6 %, respectively. The assay was applied to test field samples and detected single and mixed viral infections. The detection rate was higher than that of uniplex conventional PCR and RT-PCR methods. The detection of PRRSV by the bead-based multiplex assay was comparable with a commercially available real time RT-PCR kit. The test procedure on purified DNA or RNA samples could be completed within 2 h. In conclusion, the bead-based suspension array presented here proved to be a high-throughput practical tool that provided highly specific and sensitive identification of single and multiple infections of five major viruses in pigs and boar semen.


Assuntos
Circovirus/isolamento & purificação , Vírus da Febre Suína Clássica/isolamento & purificação , DNA Viral/isolamento & purificação , Parvovirus Suíno/isolamento & purificação , Vírus da Síndrome Respiratória e Reprodutiva Suína/isolamento & purificação , RNA Viral/isolamento & purificação , Animais , Circovirus/classificação , Peste Suína Clássica/diagnóstico , Peste Suína Clássica/virologia , Primers do DNA , DNA Viral/genética , Reação em Cadeia da Polimerase Multiplex , RNA Viral/genética , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Manejo de Espécimes , Suínos/virologia , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia
19.
Plasmid ; 74: 9-14, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24864033

RESUMO

OBJECTIVES: To learn the prevalence of the primary classical broad-host-range (BHR) IncA/C, IncN, IncP, IncQ, and IncW plasmids in dominant gram-negative bacilli from inpatients in a teaching hospital in southern China. METHODS: A multiplex polymerase chain reaction based on the replicons of BHR IncA/C, IncN, IncP, IncQ, and IncW plasmids was developed and used to determine these BHR plasmids. The difference in prevalence rates among the different species from three specimens was evaluated by a binary logistic regression model and the differences between multidrug-resistant organisms (MDRO) and non-MDRO were assessed using a chi-square test. RESULTS: The average positive detection percentages of the replicons were 4.3%, 3.7%, 3.0%, 2.6%, and 1.9%, respectively, for IncN, IncP, IncQ, IncW, and IncA/C in descending order. The distribution of all five BHR plasmids did not differ significantly between specimens collected from wounds and urine, although both were significantly higher than those of sputum. The prevalence rates of all five BHR plasmids in MDROs were significantly higher than those in non-MDRO for Enterobacteriaceae; however, no significant difference was seen in non-fermenting gram-negative bacilli (NFGNB). CONCLUSIONS: BHR IncA/C, IncN, IncP, IncQ, and IncW plasmids, which occur more often in bacilli from wound and urine specimens than those of sputum, are widespread in Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Enterobacter cloacae, Pseudomonas aeruginosa, and Acinetobacter baumannii strains isolated from inpatients. The prevalence rates in MDRO are higher than those in non-MDRO for Enterobacteriaceae but not significantly different for NFGNB.


Assuntos
Bacillus/genética , Bacillus/isolamento & purificação , Especificidade de Hospedeiro/genética , Plasmídeos/genética , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana/métodos , Criança , Pré-Escolar , Farmacorresistência Bacteriana , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Humanos , Lactente , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase Multiplex , Proteus mirabilis/genética , Proteus mirabilis/isolamento & purificação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/isolamento & purificação , Replicon/genética , Sensibilidade e Especificidade , Manejo de Espécimes , Adulto Jovem
20.
Lab Med ; 55(1): 56-61, 2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-37184444

RESUMO

BACKGROUND: The mortality and morbidity rates in children with lower respiratory tract infection (LRTI) remain high. OBJECTIVE: To describe the number of bacteria that is associated with leukocytes in differential diagnosis of bacterial, mycoplasma, and viral LRTI in children. METHODS: Sputum smears were Gram stained for counting single-morphology bacteria associated with leukocytes. The differential diagnostic values of bacterial number were assessed in children with LRTI. RESULTS: The area under the receiver operating characteristic (ROC) curve was 0.95 for bacterial number in the differential diagnosis of bacterial infection from mycoplasma and viral infections. The area under the ROC curve was 0.62 for procalcitonin and 0.94 for bacterial number in the differential diagnosis of bacterial infection from mycoplasma infection. CONCLUSION: The number of bacteria associated with leukocytes in sputum was valuable and rapid in differential diagnosis of bacterial infection in children with suspected bacterial, mycoplasma, and viral LRTI.


Assuntos
Infecções Bacterianas , Infecções Respiratórias , Criança , Humanos , Pró-Calcitonina , Diagnóstico Diferencial , Escarro/microbiologia , Bactérias , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/complicações , Infecções Respiratórias/microbiologia , Infecções Bacterianas/diagnóstico , Leucócitos
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