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1.
Org Lett ; 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34240601

RESUMO

An efficient cascade reaction of 1-indanylidenemalononitrile with 3-benzylidenebenzofuran-2(3H)-one divergently promoted by DABCO or chiral organocatalyst was developed under mild reaction conditions, and various spiro-dihydrofluorene-benzofuranones were produced in gratifying results, respectively. It is worth noting that both the spiro and axially chiral products can be obtained by tuning the reaction conditions. The mechanism of the transformation was also studied by quantum chemical calculations.

2.
Appl Environ Microbiol ; : AEM0093821, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34260307

RESUMO

Biofilm formation is important in both the environmental and intestinal phases of the Vibrio cholerae life cycle. Nevertheless, most studies of V. cholerae biofilm formation focus on mono-species cultures, whereas nearly all biofilm communities found in nature consist of a variety of microorganisms. Multi-species biofilms formed between V. cholerae and other bacteria in the environment and the interactions that exist between these species are still poorly understood. In this study, the influence of Escherichia coli on the biofilm formation of V. cholerae was studied in the context of both in vitro coculture and in vivo coinfection. To understand the underlying synergistic mechanisms between these two species and to investigate the role of E. coli in V. cholerae biofilm formation, different pathotypes of E. coli and corresponding deletion mutants lacking genes that influence flagella motility, curli fibers, or type I pili were cocultured with V. cholerae. Our findings demonstrate that the presence of commensal E. coli increases biofilm formation at the air-liquid interface in vitro and the generation of biofilm-like multicellular clumps in the mice feces. Examination of laboratory E. coli flagellar-motility mutants ΔfliC and ΔmotA in the dual-species biofilm formation suggests that flagellar motility plays an important role in the synergistic interaction and co-aggregation formation between V. cholerae and E. coli. This study facilitates a better understanding of how V. cholerae resides in harsh environments and colonizes the intestine. IMPORTANCE Biofilms play an important role in the V. cholerae life cycle. Until now, mono-species biofilm formation of V. cholerae has been well studied. However, in nature, bacteria live in complex microbial communities, where biofilm is mostly composed of multiple microbial species that interact to cooperate with or compete against each other. Uncovering how V. cholerae forms multi-species biofilm is critical for furthering our understanding of how V. cholerae survives in the environment and transitions to infecting the human host. In this work, the dual-species biofilm between V. cholerae and E. coli was investigated. We demonstrate that the presence of commensal E. coli increased overall biofilm formation. Furthermore, we demonstrate that the motility of E. coli flagella is important for V. cholerae and E. coli to form co-aggregation clumps in dual-species biofilm. These results shed light on a new mechanism for understanding the survival and pathogenesis of V. cholerae.

3.
Vaccine ; 2021 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-34253417

RESUMO

BACKGROUND: In China, 13-valent pneumococcal conjugate vaccine (PCV13) has been available since 2017, but only via the private market with low uptake rate. We assessed the direct effectiveness of PCV13 against community acquired pneumonia (CAP) associated with PCV13 serotype carriage (VT-CAP). METHODS: We conducted an observational cohort study of children born during 12-Dec-2016 to 30-Nov-2018 identified in the Suzhou Centers for Disease Control vaccine registry database, and who had at least one inpatient or outpatient record at the Suzhou University Affiliated Children's hospital (SCH) health-information-system (HIS) database. The vaccine registry cohort was followed through the HIS database through 30-Jun-2019 to identify hospitalized VT-CAP. Pneumococci were isolated from deep upper respiratory aspirates and serotyped with Quellung reactions. RESULTS: We included 139,127 children of whom 9024 (6.5%) received 1 + PCV13 doses (95.8% received 2 + doses). Within the total cohort, we identified 548 children hospitalized at SCH for VT-CAP, of whom 10 had received 2 + PCV13 doses. Adjusted for demographics, receipt of other childhood vaccines, and underlying medical conditions, the first visit vaccine effectiveness among children who had received 2 + PCV13 doses was 60.9% (95% CI: 25.8% to 79.4%) for VT-CAP and 17.9% (95% CI: 5.5% to 28.6%) for clinical CAP. Incidence rate reductions per 100,000 child-years of observation for all visits were 208 (95% CI: 118 to 298) for VT-CAP and 720 (95% CI: 304 to 1135) for clinical CAP. CONCLUSIONS: PCV13 was protective against hospitalized VT-CAP and clinical CAP with large associated incidence rate reductions among children living in Suzhou, China.

4.
Expert Rev Hematol ; 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34275403

RESUMO

BACKGROUND: Relapsed/refractory (R/R) classical HL (cHL) and systemic anaplastic large-cell lymphoma (sALCL) treatment options are limited in China and there is a need for new therapies. RESEARCH DESIGN AND METHODS: This single-arm, open-label, multicenter, Phase II study assessed efficacy, safety, and pharmacokinetics (PK) of single-agent brentuximab vedotin in Chinese patients with R/R cHL or sALCL. Patients received brentuximab vedotin as a 1.8 mg/kg intravenous infusion on Day 1 of a 3-week cycle (maximum 16 cycles). RESULTS: Patients (N=39) received a median of 10 cycles (range: 2-16) of brentuximab vedotin. The objective response rate was 69% (95% CI: 52-83%). Median duration of response, progression-free survival and overall survival were 12.1 months, 13.5 months (95% CI: 6.8 months-not estimable) and not reached after a median follow-up of 16.6 months. Twenty seven (69%) patients achieved an objective response (complete response: n=11 [28%]; partial response: n=16 [41%]). Brentuximab vedotin was well-tolerated with no on-study deaths. AEs were generally manageable and reversible. No new safety signals were identified. PK were consistent with those previously described in Western populations. CONCLUSION: Brentuximab vedotin had a positive benefit-risk profile for Chinese patients with R/R cHL or sALCL confirming it as a potential treatment option. CLINICAL TRIAL REGISTRATION: www.clinicaltrials.gov identifier is NCT02939014.

5.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 43(3): 406-413, 2021 Jun 30.
Artigo em Chinês | MEDLINE | ID: mdl-34238417

RESUMO

Objective To evaluate the diagnostic performance of 1.5-T non-contrast free-breathing whole-heart magnetic resonance coronary angiography(MRCA)for≥50% and≥70% coronary artery stenosis in coronary artery disease(CAD).Methods Forty-one patients clinically scheduled for invasive coronary angiography(ICA)underwent 1.5-T non-contrast free-breathing whole-heart MRCA.The diagnostic performance for≥50% and≥70% stenosis was evaluated and compared using ICA as a reference standard.Results MRCA was completed in all the 41 patients with the total acquisition time of(10.1 ± 2.2)min.The sensitivity,specificity,and accuracy of MRCA for≥50% and≥70% stenosis were 100%(95% CI:89%-100%)and 82%(95%CI:63%-94%),38%(95%CI:9%-76%)and 54%(95%CI:25%-81%),and 88%(95%CI:73%-95%)and 73%(95%CI:57%-85%)on a per-patient basis,respectively;they were 95%(95%CI:87%-99%)and 86%(95%CI:73%-95%),58%(95%CI:45%-71%)and 76%(95%CI:65%-85%),and 78%(95%CI:69%-84%)and 80%(95%CI:71%-86%)on a per-vessel basis,respectively.The sensitivity of MRCA for≥50% stenosis was higher than that for≥70% stenosis(97%vs.88%,χ 2=5.73,P=0.017),and the specificity showed an opposite trend(86% vs. 94%,χ 2=14.12,P<0.001)on a per-segment basis.Conclusions The 1.5-T non-contrast whole-heart MRCA can detect both≥50% and≥70% coronary artery stenosis with high sensitivity and accuracy.MRCA showed lower sensitivity while higher specificity for≥70% stenosis than for≥50% stenosis on a per-segment basis.


Assuntos
Estenose Coronária , Angiografia Coronária , Estenose Coronária/diagnóstico por imagem , Humanos , Angiografia por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Valor Preditivo dos Testes , Sensibilidade e Especificidade
6.
Plant Dis ; 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34270913

RESUMO

Tobacco (Nicotiana tabacum L.) is an annual, leafy, herb of the genus Nicotiana in the family Solanaceae. It is an important commercial crop in China. In 2020, a leaf spot disease was observed on tobacco leaves in commercial fields in the Hunan Province of China. Symptoms appeared as water-soaked, yellow-green spots, then turned dark brown, and coalesced into larger necrotic lesions, often leading to leaf wilt. Approximately 20% of the plants in a 50-ha area were infected, exhibiting symptomatic spots on 60% of these leaves. Symptomatic leaf samples were collected and cut into small pieces, sterilized with 70% ethanol for 10 s, 0.1% HgCl2 for 40s, rinsed with sterile distilled water for three times, plated on potato dextrose agar (PDA) and incubated at 26°C in the dark. Isolates with similar morphology were developed from ten samples. Fungal isolates produced densely, white to dark green, aerial mycelium. Conidia were straight, hyaline, aseptate, cylindrical, contained oil globules, and 15 to 25 µm × 3.0 to 4.0 µm (n=50). Appressoria were dark brown, irregularly shaped, 5.5 to 10.0 µm × 4.5 to 6.5 µm (n=50). These morphological characteristics were typical of Colletotrichum cliviicola (Yang et al. 2009). For molecular identification, the internal transcribed spacer (ITS) region of rDNA, actin (ACT), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and chitin synthase (CHS-1) genes of a representative isolate CS16-2 were amplified and sequenced using the primer pairs as described previously (Weir et al. 2012). These sequences were deposited in GenBank (GenBank Accession Nos. MW649137 for ITS, MW656181 for ACT, MW656182 for GAPDH and MW656183 for CHS-1). BLAST analysis showed that they had 99.46% to 100% identity to the corresponding sequences of C. cliviicola strains. A concatenated phylogenetic tree was generated, using the ACT, GAPDH and CHS-1 sequences of the isolate CS16-2 and other closely matching Colletotrichum species obtained from the GenBank. We found that the CS16-2 was grouped with the C. cliviicola clade with 97% bootstrap support, including the C. cliviicola strain AH1B6 (Wang et al. 2016). Pathogenicity was tested spraying 2-month-old potted tobacco plants until runoff with a conidial suspension (105 spores/ml). Leaves were mock inoculated with sterilized water. The pathogenicity tests were performed twice, with three replicate plants each. Plants were kept in humid chambers at 26°C with a 12-h photoperiod. Five days post-inoculation, the inoculated plants developed symptoms of consisting of the yellow-brown necrotic lesion resembling the symptoms that were observed in fields, while the control plants remained symptomless. C. cliviicola was re-isolated and identified by morphological and molecular methods as described above. Currently, C. cliviicola has been reported to be the causal agent of anthracnose in some plants, such as soybean (Zhou et al. 2017) and Zamioculcas zamiifolia (Barbieri et al. 2017). However, to our knowledge, this is the first report of C. cliviicola causing leaf spot on tobacco in China and even in the word. Given that the may greatly affect the yield and quality of tobacco production, growers should be prepared to manage this new disease. This work might provide further insight for disease diagnosis on tobacco as some other Colletotrichum species, such as C. fructicola (Wang et al. 2016) and C. karsti (Zhao et al. 2020), have also been responsible for anthracnose.

7.
Opt Lett ; 46(14): 3412-3415, 2021 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-34264226

RESUMO

In this Letter, an imaging spectrometer in which a freeform concave grating is the only optical component in the system is introduced. The degrees of freedom of optical freeform surfaces and a variable line-spacing (VLS) grating are used to realize imaging spectrometers. A point-by-point system design method is proposed that can generate a good initial solution rapidly. By exploring the limitations of the system specifications, it is demonstrated that the spectral dispersion, spectral resolving power, and system length can be improved significantly by using the freeform VLS concave grating. It is also found that freeform surfaces with higher degrees of freedom than a toroid can further improve system performance when using a VLS grating.

8.
Opt Lett ; 46(13): 3183-3186, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34197411

RESUMO

Due to a high Raman threshold and serious thermal effect, a challenge is to achieve efficient continuous-wave (CW) operation of a crystalline Raman laser at 1.5 µm. Based on effective thermal management and the self-Raman effect, we demonstrate, to our knowledge, the first efficient CW operation of a Nd:YVO4 Raman laser at 1.5 µm. We achieve 685 mW of CW eye-safe emission at 1524.5 nm by the use of a 20-mm-long composite Nd:YVO4 and 300-µm pump beam radius, with a diode-to-Stokes conversion efficiency of 4.8%. Lasers operating at ∼1.5µm have found many important applications in various areas such as optical communication, laser radar, laser ranging, remote sensing, and spectral research.

9.
Se Pu ; 39(4): 376-383, 2021 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-34227757

RESUMO

The ratio of stable isotopes of the elements in explosives differs depending on the raw materials obtained from different geographical sources or the production processes adopted. Hence, this ratio can be used as an important index for the comparison and trace of explosives. Isotope ratio mass spectrometry (IRMS), a high-precision method for the analysis of stable isotope ratios, has evolved into a mature tool in this regard. In combination with elemental analysis, gas chromatography, liquid chromatography, etc., IRMS is widely used in food safety, environmental protection, forensic science, and other fields. IRMS also plays an important role in the comparison and trace of explosives. Since its application to distinguish trinitrotoluene (TNT) produced in different countries in 1975, IRMS has been successfully used in the analysis of various explosives. However, there is no systematic summary on the research progress on the stable isotope ratio analysis of common explosives. This paper provides a brief description of the related principle, instrumental composition, and characteristics of stable isotope ratio analysis. Methods for the stable isotope ratio analysis of common explosives such as ammonium nitrate, black powder, TNT, pentaerythritol tetranitrate (PETN), and cyclotrimethylene trinitroamine (RDX) are reviewed. The bulk stable isotopic ratio analysis method was used in most of the studies to determine the total isotope ratio of the sample. A compound-specific isotope analysis method was also employed to determine the isotope ratio of organic explosives in a complex matrix. The reported stable isotope ratios of explosives such as ammonium nitrate, black powder, and TNT produced in different countries are summarized. The discrimination ability of the stable isotope ratio for explosives is discussed. Based on the stable isotope ratio, explosives from different sources can be distinguished effectively. By combining the results of elemental analysis with the ICP-MS results, the discrimination efficiency of different samples could be further improved. The influence of relevant factors on the isotope ratio during the production and storage of explosives are collated. There is a strong correlation between the stable isotope ratios of explosives and raw materials. The stable isotope ratios of TNT, PETN, and other explosives are related to that of nitric acid used in the production. The stable isotope ratios of nitrogen and oxygen in the explosive are relatively stable and almost unchanged within one year of production. The complexity of the environmental matrix at the explosion site and the low concentration of explosive residues make the stable isotope analysis of explosive residues challenging. However, the changes in the stable isotope ratio before and after the explosion are discussed. Since there is no information on the application of stable isotope analysis to the traceability of explosives, the paper mentions that the standardized explosive sample pretreatment, stable isotope analysis method, collection and analysis of large amounts of explosive samples, and explosive stable isotope database are the basis of explosive traceability. This paper also outlines the existing challenges in the analysis of the stable isotope ratios of explosives, including the small number of explosive samples, lack of a stable isotope explosive analysis database, and difficulty in the stable isotope analysis of explosive residues. Possible solutions to these problems are proposed, followed by suggestions for the future development of the stable isotope ratio analysis of common explosives. The suggestions include establishing an effective extraction and enrichment method for explosive residues, combining IRMS with GC or LC for analyzing explosives, establishing a comprehensive process for the analysis of the stable isotope ratios of inorganic and organic explosives, and comparison and analysis of the stable isotope analysis data using statistical methods.

10.
Chem Asian J ; 2021 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-34101364

RESUMO

Due to consumption of more than 2% of the world's annual energy supply by Haber-Bosch process and the strongest triple bond (N≡N) in nature, directly coupling N2 with small molecules is particularly important and challenging, let alone in a catalytic fashion. Here we first demonstrate that a NNN-type pincer phosphorus complex could act as a catalyst to couple dinitrogen with a series of small molecules including carbon dioxide, formaldehyde, N-ethylidenemethylamine, and acetonitrile in the presence of diborane(4) under a mild condition by theoretical calculations. N2 fixation proceeds via a stepwise mechanism involving initial N2 activation by diborane(4), followed by intramolecular isomerization to a key intermediate (zwitterion). Such a zwitterion can be used to couple a series of small molecules with activation barriers of 23.5-25.2 kcal mol-1 . All these findings could be particularly useful for main group chemistry aimed at N2 activation.

11.
JMIR Med Educ ; 7(2): e24358, 2021 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-34142976

RESUMO

BACKGROUND: The inverted classroom model differs from the traditional teaching model as it reverses the pattern of knowledge transfer and internalization. In recent years, this new teaching model has received much attention in undergraduate medical education. Pathophysiology is a course in the undergraduate Chinese medical curriculum that is critical in bridging basic medical science and clinical medicine. OBJECTIVE: The purpose of this study was to investigate the application of inverted classroom in delivering the course on pathophysiology to Chinese undergraduate medical students. METHODS: In the spring semester of 2018, inverted classroom teaching was implemented for second-year clinical medicine students at the College of Medicine at Nanchang University. The topics of hypoxia and respiratory failure were selected for the inverted classroom study. The effect of the inverted classroom on teaching pathophysiology was evaluated using classroom performance metrics, a final examination, and questionnaires. RESULTS: This study found that students in the inverted classroom group achieved higher scores in their in-course assessments (82.35 [SD 11.45] vs 81.33 [SD 9.51], respectively) and in their final exams (73.41 [SD 10.37] vs 71.13 [SD 11.22], respectively) than those in the traditional lecture-based group, but the scores were not significantly different (P=.13, unpaired two-tailed t test). There was also no significant difference in the distribution of the score segments in the class quiz (P=.09, chi-square test) and in the final exams (P=.25, chi-square test) between the 2 groups. Further, most of the students reported that the inverted classroom increased their learning motivation, made them more confident, and helped them understand the content on pathophysiology better. The students in the inverted classroom also improved in their problem-solving skills and teamwork abilities. However, some students from the inverted classroom group also reported that the self-learning and preparatory work before class increased their learning burden. CONCLUSIONS: This study shows the feasibility and promise of inverted classroom for teaching pathophysiology to undergraduate Chinese medical students. The inverted classroom improves students' learning interests and attitudes toward learning. However, further studies are required to assess the benefits of broader acceptance and implementation of the inverted classroom among Chinese undergraduate medical students.

12.
Chem Commun (Camb) ; 57(55): 6776-6779, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34137399

RESUMO

We report the straightforward synthesis of ATP-responsive nanoscale metal azolate framework-7 (MAF-7) for gene/drug codelivery. The MAF-7 functions as (i) the armour to preserve DNAzymes, (ii) an ATP scavenger to lower the intracellular ATP level, and (iii) a built-in Zn2+ arsenal to initiate the biocatalysis of DNAzymes, ultimately inhibiting P-gp expression to enhance chemotherapy.

13.
Anal Chem ; 93(24): 8536-8543, 2021 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-34107211

RESUMO

Nitric oxide (NO) is a molecule of physiological importance, and the function of NO depends on its concentration in biological systems, particularly in cells. Concentration-based analysis of intracellular NO can provide insight into its precise role in health and disease. However, current methods for detecting intracellular NO are still inadequate for quantitative analysis. In this study, we report a quantitative mass spectrometry probe approach to measure NO levels in cells. The probe, Amlodipine (AML), comprises a Hantzsch ester group that reacts with NO to form a pyridine, Dehydro Amlodipine (DAM). Quantification of DAM by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) allows specific measurement of intracellular NO levels. Notably, the AML/NO reaction proceeds rapidly (within 1 s), which is favorable for NO detection considering its large diffusivity and short half-life. Meanwhile, studies under simulated physiological conditions revealed that the AML response to NO is proportional and selective. The presented UPLC-MS/MS method showed high sensitivity (LLOQ = 0.24 nM) and low matrix interference (less than 15%) in DAM quantification. Furthermore, the mass spectrometry probe approach was demonstrated by enabling the measurement of endogenous and exogenous NO in cells. Hence, the quantitative UPLC-MS/MS method developed using AML as a probe is expected to be a new method for intracellular NO analysis.


Assuntos
Óxido Nítrico , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia Líquida , Reprodutibilidade dos Testes
14.
Biochem Biophys Res Commun ; 567: 79-85, 2021 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-34144504

RESUMO

circRNAs have been suggested to modulate NSCLC tumorigenesis and drug resistance. Whether circSNX6 affects NSCLC remains unclear. In this study, we aim to investigate the role of circSNX6 in drug resistance of NSCLC exposed to cisplatin. RT-qPCR method was used to investigate expression levels of circSNX6, miR-137 and CXCL12. MTT, cell colony formation and TUNEL assays were utilized to assess cell viability, proliferation, apoptosis, respectively. Xenograft assay was conducted to examinein vivotumor growth. circSNX6 overexpression caused enhanced cell viability and proliferation of H1299 and Calu-1, while it inhibited apoptosis under cisplatin treatment. miR-137 inhibitor greatly rescued cell viability, proliferation and apoptosis of circSNX6 knockdown H1299 cells. miR-137 mimic increased ROS generation, as well as reduced GSH and SOD levels, whereas miR-137 inhibitor exerted opposing effect. circSNX6 knockdown also enhanced ROS generation, as well as decreased GSH and SOD levels. CXCL12 partially restored miR-137 mimic-modulated cell viability, proliferation and apoptosis. Herein, our group proposes circSNX6 as key regulator for drug resistance of NSCLC. The findings provide solid groundings for understanding of NSCLC pathogenesis and development of therapeutics.

15.
Neural Netw ; 143: 133-147, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-34139629

RESUMO

Inspired by the success of classical neural networks, there has been tremendous effort to develop classical effective neural networks into quantum concept. In this paper, a novel hybrid quantum-classical neural network with deep residual learning (Res-HQCNN) is proposed. We firstly analyse how to connect residual block structure with a quantum neural network, and give the corresponding training algorithm. At the same time, the advantages and disadvantages of transforming deep residual learning into quantum concept are provided. As a result, the model can be trained in an end-to-end fashion, analogue to the backpropagation in classical neural networks. To explore the effectiveness of Res-HQCNN , we perform extensive experiments for quantum data with or without noisy on classical computer. The experimental results show the Res-HQCNN performs better to learn an unknown unitary transformation and has stronger robustness for noisy data, when compared to state of the arts. Moreover, the possible methods of combining residual learning with quantum neural networks are also discussed.

16.
Artigo em Inglês | MEDLINE | ID: mdl-34097222

RESUMO

Contamination of soils by nickel (Ni) has become a serious environmental problem throughout the world, and this substance wields dangerous effects on the ecosystem and food chain. A pot experiment was conducted to examine the effect of rice straw (RS), rice straw biochar (BI), and calcite (CC) at 1% and 2% application rates in a Ni-contaminated soil. The objective was to potentially stabilize Ni and reduce its bioavailability to spinach (Spinacia Oleracea L.). Spinach plants were grown in a Ni-contaminated Ultisol (commonly known as a red clay soil). Plant growth parameter results indicated that a BI 2% application rate significantly increased the root and shoots dry biomass increased by 1.7- and 6.3-fold, respectively, while essential nutrients were enhanced in the spinach plant compared to those in the untreated soil (CK). Moreover, adding amendments significantly decreased CaCl2 extractable Ni by 62.5% 94.1%, and 87.2%, while the toxicity characteristics leaching procedure (TCLP) fell by 26.7%, 47.8%, and 41.7% when using RS, BI, and CC, respectively, at 2% compared to CK. The Ni concentrations in the spinach roots declined by 51.6%, 73.3%, and 68.9%, and in the shoots reduced by 54.1%, 76.7%, and 70.8% for RS, BI, and CC, at a 2% application rate, respectively. Bio-concentration factor (BCF) and translocation factor (TF) dropped significantly by as much as 72.7% and 20%, respectively, for BI 2% application rate. Results of the present study clearly indicated that biochar potential soil amendments for Ni stabilization, thereby reducing its bioavailability in the Ni-contaminated soil. This process enhanced the safety of food to be consumed and mitigated security risks.

17.
Clin Cancer Res ; 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34108177

RESUMO

Purpose: Enfortumab vedotin (EV) is an antibody-drug conjugate (ADC) targeting NECTIN4 (encoded by the PVRL4/NECTIN4 gene) approved for treatment-refractory metastatic urothelial cancer. Factors that mediate sensitivity or resistance to EV are unknown. In the present study, we sought to 1) examine heterogeneity of NECTIN4 gene expression across molecular subtypes of bladder cancer and 2) determine if NECTIN4 expression mediates EV sensitivity or resistance. Experimental Design: Molecular subtyping and NECTIN4 expression data from seven muscle-invasive bladder cancer clinical cohorts (n=1,915 total specimens) were used to assess NECTIN4 expression across molecular subtypes. The outcome of the transcriptomic analysis was relative NECTIN4 expression in the consensus molecular subtypes of bladder cancer. Expression of NECTIN4 was validated in bladder cancer cell lines. NECTIN4 was stably over-expressed or knocked down in basal and luminal bladder cancer cell lines and EV drug sensitivity assays were performed, as measured by cell proliferation and clonogenic assays. Results: NECTIN4 expression is heterogenous across molecular subtypes of bladder cancer and significantly enriched in luminal subtypes. NECTIN4 expression is positively correlated with luminal markers GATA3, FOXA1, and PPARG across all cohorts. NECTIN4 expression is both necessary and sufficient for EV sensitivity in luminal and basal subtypes of urothelial bladder cancer cells. Downregulation of NECTIN4 leads to EV resistance. Conclusions: Sensitivity to EV is mediated by expression of NECTIN4, which is enriched in luminal subtypes of bladder cancer. These findings may have implications for biomarker development, patient selection and the inclusion of molecular subtyping in ongoing and future EV clinical trials.

18.
BMC Plant Biol ; 21(1): 255, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34082694

RESUMO

BACKGROUND: Rice (Oryza sativa) bacterial leaf blight (BLB), caused by the hemibiotrophic Xanthomonas oryzae pv. oryzae (Xoo), is one of the most devastating diseases affecting the production of rice worldwide. The development and use of resistant rice varieties or genes is currently the most effective strategy to control BLB. RESULTS: Here, we used 259 rice accessions, which are genotyped with 2 888 332 high-confidence single nucleotide polymorphisms (SNPs). Combining resistance variation data of 259 rice lines for two Xoo races observed in 2 years, we conducted a genome-wide association study (GWAS) to identify quantitative trait loci (QTL) conferring plant resistance against BLB. The expression levels of genes, which contains in GWAS results were also identified between the resistant and susceptible rice lines by transcriptome analysis at four time points after pathogen inoculation. From that 109 candidate resistance genes showing significant differential expression between resistant and susceptible rice lines were uncovered. Furthermore, the haplotype block structure analysis predicted 58 candidate genes for BLB resistance based on Chr. 7_707158 with a minimum P-value (-log 10 P = 9.72). Among them, two NLR protein-encoding genes, LOC_Os07g02560 and LOC_Os07g02570, exhibited significantly high expression in the resistant line, but had low expression in the susceptible line of rice. CONCLUSIONS: Together, our results reveal novel BLB resistance gene resources, and provide important genetic basis for BLB resistance breeding of rice crops.


Assuntos
Regulação da Expressão Gênica de Plantas , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Oryza/genética , Doenças das Plantas/microbiologia , Transcriptoma , Regulação da Expressão Gênica de Plantas/imunologia , Genótipo , Haplótipos , Doenças das Plantas/genética , Polimorfismo de Nucleotídeo Único , Locos de Características Quantitativas
19.
Front Endocrinol (Lausanne) ; 12: 651534, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34122333

RESUMO

Background: Universal salt iodization (USI) was implemented in mainland China in 1996. The prevalence of hyperthyroidism and its risk factors now require examination. Methods: Data were acquired from a nationwide Thyroid, Iodine, and Diabetes Epidemiological survey (TIDE 2015-2017) of 78,470 subjects from 31 provinces. Iodine status, and thyroid hormones and antibodies were measured. Results: After two decades of USI, the prevalence of overt hyperthyroidism (OH), Graves' disease (GD), severe subclinical hyperthyroidism (severe SCH), and mild subclinical hyperthyroidism (mild SCH) in mainland China was 0.78%, 0.53%, 0.22%, and 0.22%, respectively. OH and GD prevalence were higher in women than in men (OH: 1.16% vs. 0.64%, P<0.001; GD: 0.65% vs. 0.37%, P<0.001).Prevalence was significantly decreased after 60 years-of-age compared with 30-39 years-of-age (OH:0.61% vs. 0.81%, P<0.001; GD: 0.38% vs. 0.57%, P<0.001).Excessive iodine(EI) and deficient iodine(DI) were both related to increased prevalence of OH (odds ratio [OR] 2.09, 95% confidence interval [CI] 1.68-2.59; OR1.35, 95%CI 1.07-1.72, respectively); however, only deficient iodine was associated with increased prevalence of GD (OR1.67, 95%CI 1.30-2.15). Increased thyroid peroxidase antibody and thyroglobulin antibody levels were significantly associated with prevalence of OH and GD, but not severe SCH and mild SCH. Although hyperthyroidism was more prevalent in women, the association disappeared after adjusting for other factors such as antibody levels. Conclusion: OH and GD prevalences in mainland China are stable after two decades of USI. Iodine deficiency, elevated thyroid antibody levels, and middle age are the main risk factors for OH and GD. The severe SCH population, rather than the mild SCH population, shows similar characteristics to the OH population.

20.
Invest Ophthalmol Vis Sci ; 62(7): 3, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-34061951

RESUMO

Purpose: To investigate the effects of ex vivo-induced bone marrow myeloid-derived suppressor cells (BM-MDSCs) on allogeneic immune responses in corneal transplantation. Methods: Bone marrow cells from C57BL/6J (B6) mice were cultured with IL-6 and GM-CSF for four days. The ex vivo induction of the BM-MDSCs was assessed using flow cytometry, inducible nitric oxide synthase (iNOS) mRNA expression using reverse transcription-quantitative polymerase chain reaction, and nitric oxide (NO) production in allogeneic stimulation. T-cell proliferation and regulatory T-cell (Treg) expansion were investigated on allogeneic stimulation in the presence of ex vivo-induced BM-MDSCs. IFN-γ, IL-2, IL-10, and TGF-ß1 protein levels were measured using enzyme-linked immunosorbent assays. After subconjunctival injection of ex vivo-induced BM-MDSCs, the migration of the BM-MDSCs into corneal grafts, allogeneic corneal graft survival, neovascularization, and lymphangiogenesis were assessed using flow cytometry, slit-lamp microscopy, and immunohistochemistry. Results: The combination of GM-CSF and IL-6 significantly induced BM-MDSCs with increased iNos mRNA expression. The ex vivo-induced BM-MDSCs promoted NO release in allogeneic stimulation in vitro. The ex vivo-induced BM-MDSCs inhibited T-cell proliferation and promoted Treg expansion. Decreased IFN-γ and increased IL-2, IL-10, and TGF-ß1 production was observed in coculture of ex vivo-induced BM-MDSCs. Injected ex vivo-induced BM-MDSCs were confirmed to migrate into the grafts. The injected BM-MDSCs also prolonged corneal graft survival and prevented angiogenesis and lymphangiogenesis. Conclusions: The ex vivo-induced BM-MDSCs have suppressive effects on allogeneic immune responses and prolong corneal allograft survival via the iNOS pathway, indicating that they may be a potential therapeutic tool for corneal transplantation.

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