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2.
Bioorg Med Chem Lett ; : 128095, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33965530

RESUMO

Human esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers in human digestive system. It is necessary to discover novel antitumor agents for the treatment of esophageal cancers because of its poor prognosis. Indoline has been reported as an efficient anticancer fragment to design novel anticancer agents. In this work, indoline derivatives were designed, synthesized and explored their anticancer activity. Compound 9d, which exhibited potent antiproliferative activity with IC50 values of 1.84 µM (MGC-803 cells), 6.82 µM (A549 cells), 1.61 µM (Kyse30 cells), 1.49 µM (Kyse450 cells), 2.08 µM (Kyse510 cells) and 2.24 µM (EC-109 cells), respectively. The most active compound 9d was identified as a tubulin inhibitor targeting colchicine binding site with an IC50 value of 3.4 µM. Compound 9d could strongly suppress the tubulin polymerization in Kyse450 cells. The results of molecular docking also suggested compound 9d could tightly bind into the colchicine binding site of tubulin. Besides, compound 9d inhibited the growth of KYSE450 cells in a time and dose-dependent manner. All the results suggest that the indoline derivatives may be a class of novel tubulin inhibitors with potential anticancer activity, and which is worthy of further study.

4.
Biomed Res Int ; 2021: 6628016, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33954186

RESUMO

Aim: This study is aimed at exploring the relationship between green behavior intentions and green behavior and analyzing the moderating role of ethical leadership in this relationship. Background: Nurses' green behavior can directly reduce costs and protect the natural environment and organizational sustainability by saving resources and energy. It is not clear how green behavior intention affects green behavior or how the positive influence of green behavior intention on green behavior can be enhanced. Design and Methods. This is a cross-sectional study, and the surveys are collected from 3 hospitals in China. Of the initial cohort of 489 nurses, 89.6% were female. There were 327 subjects (66.9%) aged 35 or less, 267 subjects (54.6%) with 10 years or less of work experience, and 220 unmarried subjects (44.9%). Data were collected from January to July 2018, using three surveys: green behavior intentions, green behavior, and ethical leadership. Results: Green behavior intentions impacted employee green behavior (b = 0.32, t = 5.37, p < 0.01). The interaction term for green behavior intentions and ethical leadership was significant (b = 0.28, t = 2.53, p ≤ 0.01); the conditional direct effect of green behavior intentions was only significant at a high level of ethical leadership (conditional effect = 0.53, SE = 0.16, t = 3.38, p < 0.01, 95% confidence interval of 0.22-0.84). Conclusion: The intention to engage in green behavior influences nurses' green behavior positively, and the relationship is stronger when ethical leadership is high in the organization than when ethical leadership is low. The results of this study can help both academics and practitioners to understand the micromechanism of environmentally sustainable development in more detail and to identify the mechanisms and boundary conditions of green behavioral intentions, green behavior, and ethical leadership.

5.
Rice (N Y) ; 14(1): 35, 2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33847838

RESUMO

BACKGROUND: Chromosome segment substitution lines (CSSLs) can be used to dissect complex traits, from which single-segment substitution lines (SSSLs) containing a target quantitative trait loci (QTL) can be developed, and they are thus important for functional analysis and molecular breeding. RESULTS: A rice line with short wide grains, CSSL-Z563, was isolated from advanced-generation backcross population (BC3F6) derived from 'Xihui 18' (the recipient parent) and 'Huhan 3' (the donor parent). Z563 carried seven segments from 'Huhan 3', distributed on chromosomes 3, 7, and 8, with average substitution length of 5.52 Mb. Eleven QTLs for grain size were identified using secondary F2 population of 'Xihui 18'/Z563. The QTLs qGL3-1, qGL3-2, and qGL7 control grain length in Z563 and have additive effects to reduce grain length; qGW3-1 and qGW3-2 control grain width in Z563 and have additive effects to increase grain width. Four SSSLs, three double-segment substitution lines (D1-D3), and two triple-segment substitution lines (T1 and T2) were developed containing the target QTLs. The genetic stability of eight QTLs, including qGL3-2, qGL3-1, and qGL7, was verified by the SSSLs. D1 (containing qGL3-2 and qGL3-1), D2 (qGL3-1 and qGL7), and T1 (qGL3-2, qGL3-1, and qGL7) had positive epistatic effects on grain length, and their grain length was shorter than that of the corresponding SSSLs. The QTL qGL3-2 was fine-mapped to a 696 Kb region of chromosome 3 containing five candidate genes that differed between 'Xihui 18' and Z563. These results are important for functional research on qGL3-2 and molecular breeding of hybrid rice cultivars. CONCLUSIONS: The short and wide grain of Z563 was mainly controlled by qGL3-1, qGL3-2, qGL7, qGW3-1 and qGW3-2. The major QTL qGL3-2 was fine-mapped to a 696 Kb region of chromosome 3 containing five candidate genes. Different QTLs pyramiding displayed various phenotypes. In essence, the performance after pyramiding of genes depended on the comparison between the algebraic sum of the additive and epistatic effects of QTLs in the pyramidal line and the additive effect value of the single QTL. The results lay good foundation in the functional analysis of qGL3-2 and molecular design breeding of novel hybrid rice cultivars.

6.
Ophthalmology ; 2021 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-33857574

RESUMO

COVID-19 quarantine provides the largest intervention data of myopia progression in schoolchildren. We found grade is an important risk factor, and COVID-19-induced modifications of student's online time and outdoor activity time sufficiently change myopia progression.

7.
Nucleic Acids Res ; 49(7): 4008-4019, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33721016

RESUMO

The compact CRISPR/Cas9 system, which can be delivered with their gRNA and a full-length promoter for expression by a single adeno-associated virus (AAV), is a promising platform for therapeutic applications. We previously identified a compact SauriCas9 that displays high activity and requires a simple NNGG PAM, but the specificity is moderate. Here, we identified three compact Cas9 orthologs, Staphylococcus lugdunensis Cas9 (SlugCas9), Staphylococcus lutrae Cas9 (SlutrCas9) and Staphylococcus haemolyticus Cas9 (ShaCas9), for mammalian genome editing. Of these three Cas9 orthologs, SlugCas9 recognizes a simple NNGG PAM and displays comparable activity to SaCas9. Importantly, we generated a SlugCas9-SaCas9 chimeric nuclease, which has both high specificity and high activity. We finally engineered SlugCas9 with mutations to generate a high-fidelity variant that maintains high specificity without compromising on-target editing efficiency. Our study offers important minimal Cas9 tools that are ideal for both basic research and clinical applications.

8.
Pathogens ; 10(3)2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33668946

RESUMO

Patients with antiretroviral therapy interruption have a high risk of virological failure when re-initiating antiretroviral therapy (ART), especially those with HIV drug resistance. Next-generation sequencing may provide close scrutiny on their minority drug resistance variant. A cross-sectional study was conducted in patients with ART interruption in five regions in China in 2016. Through Sanger and next-generation sequencing in parallel, HIV drug resistance was genotyped on their plasma samples. Rates of HIV drug resistance were compared by the McNemar tests. In total, 174 patients were included in this study, with a median 12 (interquartile range (IQR), 6-24) months of ART interruption. Most (86.2%) of them had received efavirenz (EFV)/nevirapine (NVP)-based first-line therapy for a median 16 (IQR, 7-26) months before ART interruption. Sixty-one (35.1%) patients had CRF07_BC HIV-1 strains, 58 (33.3%) CRF08_BC and 35 (20.1%) CRF01_AE. Thirty-four (19.5%) of the 174 patients were detected to harbor HIV drug-resistant variants on Sanger sequencing. Thirty-six (20.7%), 37 (21.3%), 42 (24.1%), 79 (45.4%) and 139 (79.9) patients were identified to have HIV drug resistance by next-generation sequencing at 20% (v.s. Sanger, p = 0.317), 10% (v.s. Sanger, p = 0.180), 5% (v.s. Sanger, p = 0.011), 2% (v.s. Sanger, p < 0.001) and 1% (v.s. Sanger, p < 0.001) of detection thresholds, respectively. K65R was the most common minority mutation, of 95.1% (58/61) and 93.1% (54/58) in CRF07_BC and CRF08_BC, respectively, when compared with 5.7% (2/35) in CRF01_AE (p < 0.001). In 49 patients that followed-up a median 10 months later, HIV drug resistance mutations at >20% frequency such as K103N, M184VI and P225H still existed, but with decreased frequencies. The prevalence of HIV drug resistance in ART interruption was higher than 15% in the survey. Next-generation sequencing was able to detect more minority drug resistance variants than Sanger. There was a sharp increase in minority drug resistance variants when the detection threshold was below 5%.

9.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-33658363

RESUMO

Blood pH is tightly maintained between 7.35 and 7.45, and acidosis (pH <7.3) indicates poor prognosis in sepsis, wherein lactic acid from anoxic tissues overwhelms the buffering capacity of blood. Poor sepsis prognosis is also associated with low zinc levels and the release of High mobility group box 1 (HMGB1) from activated and/or necrotic cells. HMGB1 added to whole blood at physiological pH did not bind leukocyte receptors, but lowering pH with lactic acid to mimic sepsis conditions allowed binding, implying the presence of natural inhibitor(s) preventing binding at normal pH. Testing micromolar concentrations of divalent cations showed that zinc supported the robust binding of sialylated glycoproteins with HMGB1. Further characterizing HMGB1 as a sialic acid-binding lectin, we found that optimal binding takes place at normal blood pH and is markedly reduced when pH is adjusted with lactic acid to levels found in sepsis. Glycan array studies confirmed the binding of HMGB1 to sialylated glycan sequences typically found on plasma glycoproteins, with binding again being dependent on zinc and normal blood pH. Thus, HMGB1-mediated hyperactivation of innate immunity in sepsis requires acidosis, and micromolar zinc concentrations are protective. We suggest that the potent inflammatory effects of HMGB1 are kept in check via sequestration by plasma sialoglycoproteins at physiological pH and triggered when pH and zinc levels fall in late stages of sepsis. Current clinical trials independently studying zinc supplementation, HMGB1 inhibition, or pH normalization may be more successful if these approaches are combined and perhaps supplemented by infusions of heavily sialylated molecules.


Assuntos
Acidose/sangue , Proteína HMGB1/sangue , Sepse/sangue , Sialoglicoproteínas/sangue , Zinco/sangue , Acidose/imunologia , Acidose/metabolismo , Acidose/patologia , Proteínas de Transporte , Proteína HMGB1/farmacologia , Humanos , Concentração de Íons de Hidrogênio , Imunidade Inata , Lipopolissacarídeos/farmacologia , Polissacarídeos/química , Sepse/imunologia , Sepse/patologia , Ácidos Siálicos/química , Sialoglicoproteínas/química , Zinco/metabolismo
10.
Abdom Radiol (NY) ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33660041

RESUMO

PURPOSE: To investigate the computed tomography (CT) and magnetic resonance imaging (MRI) characteristics of ovarian serous borderline tumors (SBTs), and evaluate whether CT and MRI can be used to distinguish micropapillary from typical subtypes. MATERIALS AND METHODS: We retrospectively reviewed the clinical features and CT and MR imaging findings of 47 patients with SBTs encountered at our institute from September 2013 to December 2019. 30 patients with 58 histologically proven typical SBT and 17 patients with 26 micropapillary SBT were reviewed. Preoperative CT and MR images were evaluated, by two observers in consensus for the laterality, maximum diameter (MD), morphology patterns, internal architecture, attenuation or signal intensity, ADC value, enhancement patterns of solid portions (SP), and extra-ovarian imaging features. RESULTS: The median age were similar between typical SBT and SBT-MP (32.5 years, 36 years, respectively, P>0.05). Morphology patterns between two subtypes were significantly different on CT and MR images (P < 0.001). Irregular solid tumor (21/37, 56.76%) was the major morphology pattern of typical SBT tumor, while unilocular cyst with mural nodules (14/20, 70%) was the major morphology pattern of SBT-MP on CT images. Similarly, papillary architecture with internal branching (PA&IB) (17/21, 80.95%) was the major morphology pattern of typical SBT tumor, while unilocular cyst with mural nodules (4/6, 66.67%) was the major pattern of SBT-MP on MR images. PA&IB all showed slightly hyperintense papillary architecture with hypointense internal branching on T2-weighted MRI. More calcifications were found in typical SBT (24/37, 64.86%) than SBT-MP mass lesion (6/20, 30%) (P < 0.05). Hemorrhage was less frequently visible in (20/37, 54.05%) typical SBT lessons than SBT-MP mass lesion (18/20, 90%) (P < 0.05). The ovarian preservation is more seen in typical SBT (38/58, 65.52%) than SBT-MP (12/28, 42.86%) in our series (P < 0.05). Mean ADC value of solid portions (papillary architecture and mural nodules) was 1.68 (range from 1.44 to 1.85) × 10-3 mm2/s for typical SBT and 1.62 (range from 1.45 to 1.7) × 10-3 mm2/s for that of SBT-MP. The solid components of the two SBT subtypes showed wash-in appearance enhancements after contrast injection both in CT and MR images except 2 of SBT-MP with no enhancement as complete focal hemorrhage on MR images. CONCLUSION: Morphology and internal architecture are two major imaging features that can help to distinguish between SBT-MP and typical SBT.

11.
Commun Biol ; 4(1): 198, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33580179

RESUMO

Cystatin C (Cst-3) is a potent inhibitor of cysteine proteases with diverse biological functions. As a secreted protein, the potential interaction between Cst-3 and extracellular matrix components has not been well studied. Here we investigated the interaction between Cst-3 and heparan sulfate (HS), a major component of extracellular matrix. We discovered that Cst-3 is a HS-binding protein only at acidic pH. By NMR and site-directed mutagenesis, we identified two HS binding regions in Cst-3: the highly dynamic N-terminal segment and a flexible region located between residue 70-94. The composition of the HS-binding site by two highly dynamic halves is unique in known HS-binding proteins. We further discovered that HS-binding severely impairs the inhibitory activity of Cst-3 towards papain, suggesting the interaction could actively regulate Cst-3 activity. Using murine bone tissues, we showed that Cst-3 interacts with bone matrix HS at low pH, again highlighting the physiological relevance of our discovery.

12.
Am J Physiol Gastrointest Liver Physiol ; 320(5): G700-G711, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33624527

RESUMO

This study was designed to investigate whether transcutaneous auricular vagal nerve stimulation (taVNS) would be able to improve major pathophysiologies of functional dyspepsia (FD) in patients with FD. Thirty-six patients with FD (21 F) were studied in two sessions (taVNS and sham-ES). Physiological measurements, including gastric slow waves, gastric accommodation, and autonomic functions, were assessed by the electrogastrogram (EGG), a nutrient drink test and the spectral analysis of heart rate variability derived from the electrocardiogram (ECG), respectively. Thirty-six patients with FD (25 F) were randomized to receive 2-wk taVNS or sham-ES. The dyspeptic symptom scales, anxiety and depression scores, and the same physiological measurements were assessed at the beginning and the end of the 2-wk treatment. In comparison with sham-ES, acute taVNS improved gastric accommodation (P = 0.008), increased the percentage of normal gastric slow waves (%NSW, fasting: P = 0.010; fed: P = 0.007) and vagal activity (fasting: P = 0.056; fed: P = 0.026). In comparison with baseline, 2-wk taVNS but not sham-ES reduced symptoms of dyspepsia (P = 0.010), decreased the scores of anxiety (P = 0.002) and depression (P < 0.001), and improved gastric accommodation (P < 0.001) and the %NSW (fasting: P < 0.05; fed: P < 0.05) by enhancing vagal efferent activity (fasting: P = 0.015; fed: P = 0.048). Compared with the HC, the patients showed increased anxiety (P < 0.001) and depression (P < 0.001), and decreased gastric accommodation (P < 0.001) and %NSW (P < 0.001) as well as decreased vagal activity (fasting: P = 0.047). The noninvasive taVNS has a therapeutic potential for treating nonsevere FD by improving gastric accommodation and gastric pace-making activity via enhancing vagal activity.NEW & NOTEWORTHY Treatment of functional dyspepsia is difficult due to various pathophysiological factors. The proposed method of transcutaneous auricular vagal nerve stimulation improves symptoms of both dyspepsia and depression/anxiety, and gastric functions (accommodation and slow waves), possibly mediated via the enhancement of vagal efferent activity. This noninvasive and easy-to-implement neuromodulation method will be well received by patients and healthcare providers.

13.
Pediatr Surg Int ; 37(6): 745-754, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33538868

RESUMO

PURPOSE: Postoperative adhesive bowel obstruction (ABO) is a common complication especially in complicated appendicitis. This study aimed to analyze the risk factors for ABO following appendectomy in children with complicated appendicitis, and establish a scoring model for predicting postoperative ABO and treatment option to relieve the obstruction. METHODS: From December 2014 to January 2020, all files of consecutive patients with complicated appendicitis underwent appendectomy were reviewed. Univariate and multivariate analyses were used to screen out the risk factors of postoperative ABO, and establish a scoring model for predicting postoperative ABO and surgical relief to relieve the obstruction. RESULTS: Of the 780 patients, 87 (11.2%) had ABO following appendectomy, including 27 who underwent surgical relief. Age ≤ 6 years, overweight and obesity, duration of symptoms ≥ 36 h, C-reactive protein ≥ 99 mg/L, duration of operation ≥ 60 min, intraoperative peritoneal lavage, and postoperative flatus time ≥ 20 h were independent risk factors for postoperative ABO. The final scoring model for postoperative ABO included factors above, and exhibited a high degree of discrimination (area under the curve [AUC]: 0.937; 95% confidence interval [CI] 0.913-0.960) corresponding to an optimal cut-off value of 6: 82.8% sensitivity, 92.6% specificity. Furthermore, the scoring model showed a sensitivity of 74.1% and a specificity of 91.7% for patients wo underwent surgical relief to relieve obstruction with the optimal cut-off value of 9. CONCLUSION: Risk factors for postoperative ABO should be taken seriously in children with complicated appendicitis. The scoring model is a novel but promising method to predict postoperative ABO and provide reference for clinical decision-making to relieve the obstruction.

14.
J Org Chem ; 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33573381

RESUMO

The K2S2O8-mediated transition metal-free oxidative cross-coupling reaction of activated olefins with N-alkyl amides was developed, and the reaction gave N-allylic amides in moderate to good yield. This reaction protocol was suitable for different kinds of activated olefins.

15.
ACS Chem Neurosci ; 12(3): 462-472, 2021 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-33435671

RESUMO

Allosteric inhibitors have lately received great attention because of their unique advantages, representing a more suitable choice for combinatory therapeutics targeting resistance-relevant signaling cascades. Among the various inhibitors, an allosteric small-molecule inhibitor, JBJ-04-125-02, has been proven to be effective against EGFRT790M/L858R mutant in vivo and in vitro. Herein, an in silico approach was adopted to shed light on the deep understanding of the higher selectivity of JBJ-04-125-02 against EGFRT790M/L858R mutant than wild-type EGFR. Our results indicate that JBJ-04-125-02 prefers to bind with the EGFRT790M/L858R mutant, stabilizes the inactive conformation, and further allosterically affects the conformations and dynamics of the interlobe cleft, including both the allosteric site and the ATP-binding site. Furthermore, docking results confirm that the binding of JBJ-04-125-02 at the allosteric site decreases the binding affinity of ANP (an ATP analogue) at the orthosteric site, especially for the Mut-holo one, which might further inhibit the function of EGFR. The present work provides a clear picture of the mutant-selective inhibition mechanism of an allosteric inhibitor of EGFR. The findings might pave the way for designing allosteric drugs targeting EGFR mutant lung cancer patients, which also takes a step forward in terms of drug resistance caused by protein mutations.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33411665

RESUMO

A Gram-stain-negative, aerobic, motile, short-rod-shaped bacterium with nicosulfuron-degrading ability, designated strain LAM1902T, was isolated from a microbial consortium enriched with nicosulfuron as a sole nitrogen and energy source. The optimal temperature and pH for growth of strain LAM1902T were 30 °C and pH 6.0, respectively. Strain LAM1902T could grow in the presence of NaCl with concentration up to 4.0 % (w/v). Comparative analysis of 16S rRNA gene sequences revealed that LAM1902T was closely related to the members of the family Pseudomonadaceae to the genus Pseudomonas, with the highest similarity to Pseudomonas nitroreducens DSM 14399T (99.6 %), Pseudomonas nitritireducens WZBFD3-5A2T (99.3 %) and Pseudomonas panipatensis Esp-1T (98.8 %). Multi-locus sequence analysis based on both concatenated sequences of the 16S rRNA gene and three housekeeping genes (gyrB, rpoB and rpoD) further confirmed the intrageneric phylogenetic position of strain LAM1902T. The genomic DNA G+C content of LAM1902T was 64.8 mol%. The low values of in silico DNA-DNA hybridization (less than 43.7 %) and average nucleotide identity (less than 90.9 %) also showed that the strain was distinctly different from known species of the genus Pseudomonas. The major fatty acids were C16 : 0, C17 : 0 cyclo and anteiso C15 : 0. Ubiquinone Q-9 was detected as the predorminant respiratory quinone. The major polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and aminophospholipid. Based on phylogenetic, phenotypic and chemotaxonomic analyses and genome comparisons, we conclude that strain LAM1902T represents a novel species, for which the name Pseudomonas nicosulfuronedens sp. nov. is proposed. The type strain is LAM1902T (=JCM 33860T=KCTC 72830T).


Assuntos
Consórcios Microbianos , Filogenia , Pseudomonas/classificação , Piridinas/metabolismo , Compostos de Sulfonilureia/metabolismo , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Fosfolipídeos/química , Pseudomonas/isolamento & purificação , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Ubiquinona/química
17.
Int J Toxicol ; 40(2): 171-177, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33307919

RESUMO

Increasing evidence indicates that environmental pollutants can change human gut microbiota. Microcystin-leucine arginine (MC-LR), considered a major hazard to mammals, is one of the important contaminants. However, little is known about the long-term influence of MC-LR on gut microbial communities. We aimed to investigate the effect of MC-LR on gut microbiota composition and functions by conducting a chronic exposure of male mice to MC-LR via the oral route. Using 16S rRNA gene sequencing analysis on cecum samples of mice, our results showed that significant changes of species diversity were observed in the gut microbiota of MC-LR-exposed mice. In addition, comparative analysis of the microbial communities showed that the reduction of the Actinobacteria and Saccharibacteria populations was detected in MC-LR-exposed mice. Collectively, our study highlighted the significant effects of MC-LR on the shift of gut microbial communities which could contribute to the development of metabolic syndromes.

18.
Biosens Bioelectron ; 172: 112766, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33126177

RESUMO

The 2019 novel coronavirus disease (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected all aspects of human life. Rapid, accurate, sensitive and user friendly detection method is urgently needed to facilitate early intervention and control the spread of SARS-CoV-2. Here, we propose a one-pot visual SARS-CoV-2 detection system named "opvCRISPR" by integrating reverse transcription loop-mediated isothermal amplification (RT-LAMP) and Cas12a cleavage in a single reaction system. We demonstrate that the collateral activity against single-stranded DNA (ssDNA) reporters of activated Cas12a triggered by RT-LAMP amplicon increases detection sensitivity and makes detection results observable with naked eye. The opvCRISPR enables detection at nearly single molecule level in 45 min. We validate this method with 50 SARS-CoV-2 potentially infected clinical samples. The opvCRISPR diagnostic results provide 100% agreement with the Centers for Disease Control and Prevention (CDC)-approved quantitative RT-PCR assay. The opvCRISPR holds great potential for SARS-CoV-2 detection in next-generation point-of-care molecular diagnostics.


Assuntos
/métodos , Sistemas CRISPR-Cas , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificação de Ácido Nucleico/métodos , /genética , Sequência de Bases , /instrumentação , Humanos , Técnicas de Diagnóstico Molecular/instrumentação , Técnicas de Diagnóstico Molecular/estatística & dados numéricos , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas de Amplificação de Ácido Nucleico/estatística & dados numéricos , Pandemias , RNA Viral/genética , Sensibilidade e Especificidade
19.
Phytochemistry ; 182: 112596, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33321444

RESUMO

Phytochemical investigation of mastic, a resin produced by Pistacia lentiscus, led to the isolation and identification of 16 tirucallane triterpenoids, 13 (1-13) of which are undescribed. Their structures and absolute configurations were elucidated based on the analysis of spectroscopic data and single-crystal X-ray diffraction. Compounds 12 and 13 are unusual 7(8 â†’ 9)abeo-tirucallane triterpenoids. Anti-inflammatory assays indicated that compounds 7, 8, 14, and 16 exhibited stronger inhibitory NO production activities (IC50 = 7.7-13.4 µM) than that of the positive control dexamethasone (IC50 = 19.5 µM). In addition, compound 1 showed comparable cytotoxic activity against HepG2 cells to that of doxorubicin (IC50 = 4.92 VS 1.34 µM).


Assuntos
Antineoplásicos Fitogênicos , Pistacia , Triterpenos , Anti-Inflamatórios/farmacologia , Triterpenos/farmacologia
20.
Artigo em Inglês | MEDLINE | ID: mdl-33190833

RESUMO

Organic pollutants in electroplating wastewater can be removed by photodegradation, however the effect mechanism of heavy metal ions on photocatalytic activity still remains unknown. Herein, we firstly reported the self-assembly synthesis of titanium dioxide/reduced graphene oxide (TiO2/rGO) composites for phenol-4-sulfonic acid (PSA) removal, and investigated the effects of Cu2+ ions on photocatalytic efficiency. During the self-assemble process, rGO nanosheets were connected together to form network macropores, and simultaneously induced the deposition of hierarchically nanostructured TiO2 microspheres. The synergetic effects of TiO2 microspheres and rGO nanosheets improved the photocatalytic activity by enhancing light adsorption ability, stabilizing electron-hole separation and decreasing band gap energy. The Cu2+ ions in wastewater showed positive and negative effects on PSA photodegradation. In the photocatalytic reaction, the electron-induced reduction reaction of Cu(II) into Cu(0) or Cu(I) took place, which inhibited electron-hole recombination and thus enhanced photocatalytic activity. However, the high chemical stability of PSA-Cu(II) complex compounds held back PSA photodegradation. The appropriate concentrations of Cu2+ ions at around 25 mg/L accelerated PSA photodegradation over TiO2/rGO composites. The PSA degradation into CO2 and H2O was performed by using hydroquinone, benzoquinone and maleic acid as degradation intermediates. Hence, TiO2/rGO composites are novel multifunctional photocatalysts to purify electroplating wastewater.

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