Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 292
Filtrar
1.
J Hazard Mater ; 409: 124921, 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33421874

RESUMO

The discovery of plasmid-mediated tet(X) variants and efflux pump gene tmexCD1-toprJ1 conferring bacteria resistance to tigecycline has compromised glycylcycline as the last line of defense against infection, which poses serious threat to public health. Herein, real-time quantitative PCR was used to detect the abundance of seven tigecycline resistance genes (TRGs), including six tet(X) variants and tmexCD1-toprJ1, and insertion sequences ISCR2 and IS26. Then, the concentrations of nine antibiotics were quantified in fecal samples collected from 157 livestock farms in four Chinese provinces. TRGs, especially tet(X4), tmexCD1-toprJ1, and insertion sequences ISCR2 and IS26, were more abundant in chicken feces than in pig and cattle feces, suggesting the greater risk for the propagation of TRGs in chicken feces. Positive correlations (ρ = 0.3741-0.8275, P < 0.0001) between ISCR2/IS26 and TRGs (except tet(X1)) further demonstrated that ISCR2 mediates the transfer of tet(X3), tet(X4), and tet(X5) and that IS26 plays a certain role for the mobilization of tet(X4) and tmexCD1-toprJ1. Tetracyclines had no positive correlation with the abundance of TRGs (except tet(X1)), meanwhile florfenicol and tiamulin were positively correlated with TRGs. However, further research is needed to confirm whether or not florfenicol and tiamulin are potential driving factors of TRG accumulation.

2.
Cell Death Dis ; 12(1): 42, 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33414446

RESUMO

The regulation of homeostasis in the Ubiquitin (Ub) proteasome system (UPS) is likely to be important for the development of liver cancer. Tribbles homolog 2 (TRIB2) is known to affect Ub E3 ligases (E3s) in liver cancer. However, whether TRIB2 regulates the UPS in other ways and the relevant mechanisms are still unknown. Here, we reveal that TRIB2 decreased Ub levels largely by stimulating proteasome degradation of Ub. In the proteasome, proteasome 20S subunit beta 5 (PSMB5) was critical for the function of TRIB2, although it did not directly interact with TRIB2. However, poly (rC) binding protein 2 (PCBP2), which was identified by mass spectrometry, directly interacted with both TRIB2 and PSMB5. PCBP2 was a prerequisite for the TRIB2 induction of PSMB5 activity and decreased Ub levels. A significant correlation between TRIB2 and PCBP2 was revealed in liver cancer specimens. Interestingly, TRIB2 suppressed the K48-ubiquitination of PCBP2 to increase its level. Therefore, a model showing that TRIB2 cooperates and stimulates PCBP2 to reduce Ub levels was established. Additionally, the reduction in Ub levels induced by TRIB2 and PCBP2 was dependent on K48-ubiquitination. PCBP2 was one of the possible downstream factors of TRIB2 and their interaction relied on the DQLVPD element of TRIB2 and the KH3 domain of PCBP2. This interaction was necessary to maintain the viability of the liver cancer cells and promote tumor growth. Mechanistically, glutathione peroxidase 4 functioned as one of the terminal effectors of TRIB2 and PCBP2 to protect liver cancer cells from oxidative damage. Taken together, the data indicate that, in addition to affecting E3s, TRIB2 plays a critical role in regulating UPS by modulating PSMB5 activity in proteasome to reduce Ub flux, and that targeting TRIB2 might be helpful in liver cancer treatments by enhancing the oxidative damage induced by therapeutic agents.

3.
Artigo em Inglês | MEDLINE | ID: mdl-33398902

RESUMO

Tensile-strained Mxene/carbon nanotube (CNT) porous microspheres were developed as an electrocatalyst for the lithium polysulfide (LiPS) redox reaction. The internal stress on the surface results in lattice distortion with expanding Ti-Ti bonds, endowing the Mxene nanosheet with abundant active sites and regulating the d-band center of Ti atoms upshifted closer to the Fermi level, leading to strengthened LiPS adsorbability and accelerated catalytic conversion. The macroporous framework offers uniformed sulfur distribution, potent sulfur immobilization, and large surface area. The composite interwoven by CNT tentacle enhances conductivity and prevents the restacking of Mxene sheets. This combination of tensile strain effect and hierarchical architecture design results in smooth and favorable trapping-diffusion-conversion of LiPS on the interface. The Li-S battery exhibits an initial capacity of 1451 mAh g-1 at 0.2 C, rate capability up to 8 C, and prolonged cycle life.

4.
Food Chem ; 337: 127755, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777567

RESUMO

Since the beginning of the widespread use of pesticides, their removal from food has become a serious concern. In this study, the removal of residual pesticides (malathion and carbosulfan) from pak choi via treatment with ozonated water was investigated. Under the optimal treatment conditions, i.e., 2.0 mg/L ozonated water and a treatment duration of 15 min, malathion and carbosulfan were degraded by 53.0 and 33.0%, respectively, without any significant changes in color. Even though there was a slight decrease in vitamin C content (~7.9 mg/100 g) following the treatments, a significant decrease in the microbial colonies on the vegetables was observed. Additionally, the pesticide degradation mechanism showed good fitting with a "first + first"-order kinetic model (R2 > 0.9), and the slope (k) indicated that ozone had a more prominent degradation effect on malathion than on carbosulfan. Therefore, this study provides a theoretical basis for controlling agricultural pesticide residues in household applications.


Assuntos
Brassica rapa/química , Carbamatos/química , Carbamatos/isolamento & purificação , Malation/química , Malation/isolamento & purificação , Ozônio/química , Contaminação de Alimentos , Resíduos de Praguicidas/química , Resíduos de Praguicidas/isolamento & purificação , Verduras/química
5.
Opt Express ; 29(1): 377-384, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33362123

RESUMO

A vector ray-tracing model (VRT) has been developed to compute the optical caustics associated with the primary rainbow for an oblate spheroidal water drop illuminated by a Gaussian beam. By comparing the optical caustic structures (in terms of limiting rainbow and hyperbolic umbilic fringes) for a water drop with a Gaussian beam (GB) illumination with that for the same drop, but with parallel beam (PB) illumination, the influence of the Gaussian beam on the optical caustics is investigated. For a water drop with GB illumination and different drop/beam ratios (i.e., the ratio between the drop equatorial radius and the Gaussian beam waist), the location of cusp points and the curvature of the limiting rainbow fringe are also studied. We anticipate that these results not only confirm the approach to compute optical caustics for oblate spheroidal drops illuminated by a shaped beam, but may also lead to a new method for measuring the aspect ratio of spheroidal drops.

6.
J Pept Sci ; : e3294, 2020 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-33283388

RESUMO

With the extensive use of antibiotics in medicine, agriculture and food chemistry, the emergence of multi-drug resistant bacteria become more and more frequent and posed great threats to human health and life. So novel antimicrobial agents were urgently needed to defend the resistant bacteria. Jelleine-I was a small antimicrobial peptide (AMP) with eight amino acids in its sequence. It was believed to be an ideal template for developing antimicrobial agents. In the present study, the possible action mode against both gram-negative bacteria and gram-positive bacteria and in vivo antimicrobial activity was explored. Our results showed that Jelleine-I exhibits its antimicrobial activity mainly by disrupting the integrity of the cell membrane, which would not be affected by the conventional resistant mechanism. It also aims at some intracellular targets such as genomic DNA to inhibit the growth of microbes. In addition, the result of in vivo antimicrobial activity experiment showed that Jelleine-I performed a good therapeutic effect toward the mice with Escherichia coli infected peritonitis. Notably, Jelleine-I has negligible cytotoxicity toward the tested mammalian cells, indicating excellent cell selectivity between prokaryotic cells and eurkayotic cells. In summary, our results showed that Jelleine-I would be a potential candidate to be developed as a novel antimicrobial agent.

8.
J Pharmacol Exp Ther ; 2020 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-33318078

RESUMO

G protein-coupled estrogen receptor (GPER) might be involved in ulcerative colitis (UC), but the direct effect of GPER on UC is still unclear. We used male C57BL/6 mice to establish the acute colitis model with administration of dextran sulfate sodium (DSS), and explored the effect of GPER on acute colitis and its possible mechanism. The selective GPER agonist G-1 inhibited weight loss and colon shortening, and decreased the Disease Activity Index for colitis and histological damage in mice with colitis. All of these effects were prevented by a selective GPER blocker. G-1 administration prevented the dysfunction of tight-junction proteins expression and goblet cells in colitis model, thus inhibited the increase in mucosal permeability in colitis-suffering mice significantly. GPER activation reduced expression of glucose-regulating peptide-78 and anti-CCAAT/enhancer-binding protein homologous protein, and attenuated the three arms of the unfolded protein response in colitis. G-1 therapy inhibited the increase of cleavage caspase-3 and TUNEL positive cells in colonic crypts in the colitis model, increased the number of Ki67- and bromodeoxyuridine-positive cells in crypts, and reversed the decrease of cyclin D1 and cyclin B1 expression in colitis, indicating its protective effect on crypt cell. In cultured CCD841 cells G-1 treatment fought against cell injury induced by endoplasmic reticulum stress. These findings demonstrate that GPER activation prevents colitis by protecting the colonic crypt cells, which is associated with inhibition of endoplasmic reticulum stress. Significance Statement We demonstrate that GPER activation prevents the DSS-induced acute colitis by protecting the crypt cells, showing that it inhibited the crypt cell apoptosis and protected proliferation of crypt cell, which resulted in protection of the intestinal mucosal barrier. This protective effect was achieved (at least in part) by inhibiting ERS. Mucosal healing is regarded to be a key therapeutic target for colitis, and GPER is expected to become a new therapeutic target for colitis.

9.
Front Cell Infect Microbiol ; 10: 553837, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330119

RESUMO

Purpose: To develop a rapid detection reagent for SARS-CoV-2 antigen for the auxiliary diagnosis of new coronary pneumonia (COVID-19), and perform the methodological evaluation and clinical evaluation of the reagent. Method: SARS-CoV-2 N-protein test strip was created by combining fluorescent microsphere labeling technology and immunochromatographic technology, based on the principle of double antibody sandwich. Then we evaluated the analytical capability and clinical application of the strips. Result: The limit of detection of the strips for recombinant N protein was 100 ng/ml and for activated SARS -CoV-2 virus was 1 × 103 TCID50/ml. The strips also have high analytical specificity and anti-interference capability. According to the predetermined cut-off value, the specificity of the test strip in healthy controls and patients with other respiratory disease was 100.00 and 97.29%, the sensitivity in COVID-19 cases at progress stage and cured stage was 67.15 and 7.02%. The positive percentage agreement and negative percentage agreement of antigen strip to RNA test were 83.16 and 94.45%. Conclusion: SARS-CoV-2 fluorescence immunochromatographic test strip can achieve fast, sensitive and accurate detection, which can meet the clinical requirements for rapid detection of viruses on the spot.


Assuntos
Antígenos Virais/imunologia , /diagnóstico , /imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos Virais/análise , Criança , Pré-Escolar , Cromatografia de Afinidade/métodos , Feminino , Corantes Fluorescentes , Humanos , Limite de Detecção , Masculino , Microesferas , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Adulto Jovem
10.
Onco Targets Ther ; 13: 12015-12025, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244243

RESUMO

Purpose: Hepatocellular carcinoma (HCC) is a common malignant tumor with limited treatment. Our previous studies demonstrated that Huaier enhanced chemotherapy sensitivity and restrained HCC proliferation. This study aimed to identify differentially expressed proteins with Huaier treatment in HCC cells, providing molecular targets for future targeted therapy of HCC. Materials and Methods: The effects of Huaier on the cell cycle were determined by flow cytometry and Western blot (WB). Xenograft models were used to verify the effects of Huaier on tumor growth. Then, proteomics was performed to identify the potential proteins regulated by Huaier. The enrichment analysis of GO and KEGG was performed for the differentially expressed proteins. Western blot (WB) and immunohistochemistry (IHC) were used to detect the levels of proteins after Huaier treatment. After that the correlation of differentially expressed proteins with pathological stages was analyzed via the GEPIA database. We also analyzed candidate expression after Huaier treatment in HCC cells by WB and qRT-PCR. Furthermore, siRNA was performed to verify the targeted regulation of Huaier on candidate proteins. Results: First, the proteomics data showed that a total of 160 proteins were identified as differentially expressed proteins, among which six minichromosome maintenance (MCM) family members were enriched in the tumor-associated pathways after Huaier treatment. Moreover, MCM proteins were highly expressed in HCC and closely correlated with the survival of HCC patients. Finally, we confirmed that MCM proteins were targets of Huaier treatment in HCC cells. Conclusion: Huaier treatment was closely associated with the activation and inhibition of cancer-related pathways, and the MCM family was identified as a potential target in the antitumor process of Huaier. This study is helpful in understanding the molecular alterations and clinical relevance of HCC after Huaier treatment, which is beneficial for finding new targets and designing effective chemotherapy regimens for the future treatment of HCC.

11.
Front Psychiatry ; 11: 594466, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33244301

RESUMO

Subjects with ultra-high risk (UHR) states for psychosis show brain structural volume changes similar to first-episode psychosis and also elevated incidence of environmental risk factors like childhood trauma. It is unclear, however, whether early neurodevelopmental trajectories are altered in UHR. We screened a total of 12,779 first-year Chinese students to enroll 36 UHR subjects (based on clinical interviews) and 59 non-UHR healthy controls for a case-control study of markers of early neurodevelopment. Subjects underwent 3T MRI scanning and clinical characterization, including the childhood trauma questionnaire (CTQ). We then used the CAT12 toolbox to analyse structural brain scans for cortical surface complexity, a spherical harmonics-based marker of early neurodevelopmental changes. While we did not find statistically significant differences between the groups, a trend level finding for reduced cortical complexity (CC) in UHR vs. non-UHR subjects emerged in the left superior temporal cortex (and adjacent insular and transverse temporal cortices), and this trend level association was significantly moderated by childhood trauma (CTQ score). Our findings indicate that UHR subjects tend to show abnormal cortical surface morphometry, in line with recent research; more importantly, however, this association seems to be considerably modulated by early environmental impacts. Hence, our results provide an indication of environmental or gene × environment interactions on early neurodevelopment leading up to elevated psychosis risk.

12.
Artigo em Inglês | MEDLINE | ID: mdl-33245440

RESUMO

Laccases are versatile oxidases that are capable of decolorizing various synthetic dyes. Recombinant Bacillus amyloliquefaciens laccase was immobilized as magnetic cross-linked enzyme aggregates (M-CLEAs) for application in dye decolorization. Several parameters influencing the activity recovery were evaluated during the synthesis of M-CLEAs. With ammonium sulfate as precipitant, maximum activity was recovered by cross-linking with 0.16% glutaraldehyde for 1 h. The prepared M-CLEAs exhibited improved activity under alkaline conditions. It remained 74% activity after incubation at 60 °C for 5 h. Enhanced tolerance towards NaCl was also observed for the M-CLEAs, with 68% activity remaining in the presence of 1 M NaCl. The immobilized laccase could rapidly decolorize more than 93% of reactive black 5 and indigo carmine in 1 h, while its catalytic efficiency towards reactive blue 19 was relatively low. After four cycles of consecutive reuse, the M-CLEAs could decolorize 92% of indigo carmine. The easy recovery and reusability of M-CLEAs facilitate the potential application of bacterial laccase in dye decolorization.

13.
Redox Biol ; 38: 101801, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33232910

RESUMO

The biological functions of N6-methyladenosine (m6A) RNA methylation are mainly dependent on the reader; however, its role in lung tumorigenesis remains unclear. Here, we have demonstrated that the m6A reader YT521-B homology domain containing 2 (YTHDC2) is frequently suppressed in lung adenocarcinoma (LUAD). Downregulation of YTHDC2 was associated with poor clinical outcome of LUAD. YTHDC2 decreased tumorigenesis in a spontaneous LUAD mouse model. Moreover, YTHDC2 exhibited antitumor activity in human LUAD cells. Mechanistically, YTHDC2, via its m6A-recognizing YTH domain, suppressed cystine uptake and blocked the downstream antioxidant program. Administration of cystine downstream antioxidants to pulmonary YTHDC2-overexpressing mice rescued lung tumorigenesis. Furthermore, solute carrier 7A11 (SLC7A11), the catalytic subunit of system XC-, was identified to be the direct target of YTHDC2. YTHDC2 destabilized SLC7A11 mRNA in an m6A-dependent manner because YTHDC2 preferentially bound to m6A-modified SLC7A11 mRNA and thereafter promoted its decay. Clinically, a large proportion of acinar LUAD subtype cases exhibited simultaneous YTHDC2 downregulation and SLC7A11 elevation. Patient-derived xenograft (PDX) mouse models generated from acinar LUAD showed sensitivity to system XC- inhibitors. Collectively, the promotion of cystine uptake via the suppression of YTHDC2 is critical for LUAD tumorigenesis, and blocking this process may benefit future treatment.

14.
Int J Biol Sci ; 16(16): 3184-3199, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33162824

RESUMO

Background: Histone deacetylase (HDAC) inhibitors have emerged as a new class of anti-tumor agents for various types of tumors, including glioblastoma. Methods and results: We found that a novel HDAC inhibitor, MPT0B291, significantly reduced the cell viability and increased cell death of human and rat glioma cell lines, but not in normal astrocytes. We also demonstrated that MPT0B291 suppressed proliferation by inducing G1 phase cell cycle arrest and increased apoptosis in human and rat glioma cell lines by flow cytometry and immunocytochemistry. We further investigated the anti-tumor effects of MPT0B291 in xenograft (mouse) and allograft (rat) models. The IVIS200 images and histological analysis indicated MPT0B291 (25 mg/kg, p. o.) reduced tumor volume. Mechanistically, MPT0B291 increased phosphorylation and acetylation/activation of p53 and increased mRNA levels of the apoptosis related genes PUMA, Bax, and Apaf1 as well as increased protein level of PUMA, Apaf1 in C6 cell line. The expression of cell cycle related gene p21 was also increased and Cdk2, Cdk4 were decreased by MPT0B291. Conclusion: Our study highlights the anti-tumor efficacy of a novel compound MPT0B291 on glioma growth.

15.
Sheng Wu Gong Cheng Xue Bao ; 36(10): 1970-1978, 2020 Oct 25.
Artigo em Chinês | MEDLINE | ID: mdl-33169563

RESUMO

At present, SARS-CoV-2 is raging, and novel coronavirus pneumonia (COVID-19) has caused more than 35 million confirmed patients and more than 500 000 cases death, which seriously endanger human health, socioeconomic development, as well as global medical and public health systems. COVID-19 is highly contagious, has a long incubation period, and causes many death cases due to lack of effective specific treatment. Mesenchymal stem cells have powerful anti-inflammatory and immunoregulatory functions, and can effectively reduce the cytokine storm caused by coronavirus in patients, and improve the pulmonary fibrosis of patients, promote the repair of damaged lung tissue, and reduce the mortality. Currently, a number of related clinical trials of mesenchymal stem cell treatment of COVID-19 have been conducted, and have confirmed the safety and efficacy, suggesting a good clinical application prospect. While progress has been made in mesenchymal stem cell therapy for COVID-19, we should also catch sight of the problems and challenges faced by mesenchymal stem cell clinical trials under severe epidemic situation, including clinical trials design, stem cell quality management, and ethics in treatment. Only by paying attention to these can we guarantee the safe and effective development of mesenchymal stem cell clinical trials in the treatment of COVID-19.


Assuntos
Infecções por Coronavirus/terapia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Pneumonia Viral/terapia , Betacoronavirus , Ensaios Clínicos como Assunto , Humanos , Pandemias
16.
Br J Anaesth ; 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33039122

RESUMO

BACKGROUND: Myocardial injury after noncardiac surgery (MINS) is common, mostly silent, and a strong predictor of postoperative mortality. MINS appears to result from myocardial supply-demand mismatch. Recent data support restrictive perioperative transfusion strategies that can result in low postoperative haemoglobin concentrations. Whether low postoperative haemoglobin is associated with myocardial injury remains unknown. We therefore tested the hypothesis that anaemia is associated with an increased risk of myocardial injury in adults having noncardiac surgery. METHODS: We conducted a retrospective analysis of adults ≥45 yr old who had routine postoperative troponin T (TnT) monitoring after noncardiac surgery at the Cleverland Clinic (including those enrolled in the PeriOperative ISchemic Evaluation-2 Trial [POISE-2], the Safety of Addition of Nitrous Oxide to General Anaesthesia in At-risk Patients Having Major Non-cardiac Surgery [ENIGMA-II], Vascular Events In Noncardiac Surgery Patients Cohort Evaluation Study [VISION], and Anaesthetic Depth and Complications After Major Surgery [BALANCED] trial). Patients with baseline increase in TnT and non-ischaemic aetiologies for TnT increase were excluded. The association between postoperative haemoglobin concentration during the 3 initial postoperative days and the incidence of MINS (fourth-generation TnT ≥0.03 ng ml-1 judged as attributable to ischaemia) was assessed using a time-varying covariate Cox proportional hazards survival analysis. RESULTS: Among 6141 patients, 4480 were analysed. The incidence of MINS was 155/4480 (3.5%), ranging from 0/345 (0%) among patients whose lowest postoperative haemoglobin exceeded 13 g dl-1 to 52/611 (8.5%) in patients whose minimum postoperative haemoglobin was <8 g dl-1. The confounder-adjusted hazard ratio [95% confidence interval] for having MINS was 1.29 [1.16-1.42] for every 1 g dl-1 decrease in postoperative haemoglobin in a time-varying covariate analysis. Similar associations were identified in sensitivity analyses. CONCLUSION: Lower postoperative haemoglobin values are associated with MINS. Whether this association is modifiable by prevention or treatment of, anaemia remains to be determined.

17.
Cell Rep ; 32(11): 108133, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32937129

RESUMO

Type III CRISPR-Cas systems initiate an intracellular signaling pathway to confer immunity. The signaling pathway includes synthesis of cyclic oligo-adenylate (cOA) and activation of the RNase activity of type III accessory ribonuclease Csm6/Csx1 by cOA. After the immune response, cOA should be cleared on time to avoid constant cellular RNA degradation. In this study, we find a metal-dependent cOA degradation activity in Sulfolobus islandicus. The activity is associated with the cell membrane and able to accelerate cOA clearance at a high cOA level. Further, we show that a metal-dependent and membrane-associated DHH-DHHA1 family nuclease (MAD) rapidly cleaves cOA and deactivates Csx1 ribonuclease. The cOA degradation efficiency of MAD is much higher than the cellular ring nuclease. However, the subcellular organization may prevent it from degrading nascent cOA. Together, the data suggest that MAD acts as the second cOA degrader after the ring nuclease to remove diffused redundant cOA.

18.
Zhongguo Fei Ai Za Zhi ; 23(9): 811-817, 2020 Sep 20.
Artigo em Chinês | MEDLINE | ID: mdl-32758348

RESUMO

Ferroptosis is a recently recognized form of regulated cell death caused by an iron-dependent accumulation of lipid reactive species. However, little research on ferroptosis and lung cancer, one of the most common tumors, has been carried out. This paper tries to review the research progress of ferroptotic suppression and explain it from the different ways of ferroptosis occurrence. Furthermore, as inducing ferroptosis to treat cancer gets more attention, we introduce four kinds of ferroptosis-inducing compounds and new prospects for lung cancer therapy to provide new ideas for lung cancer treatment.

19.
Ecotoxicol Environ Saf ; 205: 111144, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32846295

RESUMO

Cadmium (Cd) contamination is the most common and extensive heavy metal pollution in the farmland of China. Phytoremediation is considered as a promising measure for Cd-contaminated soil remediation, but the remediation efficiency still needs to be enhanced. Biochar as an effective amendment medium is widely manufactured and studied for the soil remediation of heavy metals. In this study, a greenhouse pot trial was conducted to investigate the effects of cornstalk biochar on Cd accumulation of Beta vulgaris var. cicla L. (Beta vulgaris) in Cd contaminated soil. The Cd availability, speciation and nutrients in soil, biomass and Cd chemical forms in the Beta vulgaris root were studied to explore the mechanism that how the cornstalk biochar promoted Cd accumulation in Beta vulgaris. Biochar amendment reduced the DTPA-extractable Cd concentration and stimulated the growth of root. Compared to the Beta vulgaris without biochar treatment, the results of 5% biochar amendment showed that the root dry weight of Beta vulgaris increased to 267%, Cd accumulation in Beta vulgaris increased to 206% and the Cd concentration in leaves and roots increased by 36% and 52%, respectively. Additionally, after 5% biochar was applied to soil, the total content of organic matter-bound Cd and residual Cd increased by 38%, while the content of Fe-Mn oxides-bound Cd decreased by 40%. Meanwhile, Cd may mainly bind to the root cell wall and the ratio of NaCl-extracted Cd to HAc-extracted Cd increased to 166% with 5% biochar amendment. According to our study, Cd in soil can be removed by Beta vulgaris and phytoremediation efficiency can be improved with biochar amendment. The combination of phytoremediation and biochar amendment is a promising strategy for the Cd-contaminated soil remediation.


Assuntos
Beta vulgaris/metabolismo , Biodegradação Ambiental , Cádmio/metabolismo , Poluentes do Solo/metabolismo , Biomassa , Carvão Vegetal , China , Metais Pesados/análise , Solo/química , Poluentes do Solo/análise
20.
Emerg Microbes Infect ; : 1-27, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32799618

RESUMO

COVID-19 is caused by SARS-CoV-2 infection and was initially discovered in Wuhan. This outbreak quickly spread all over China and then to more than 20 other countries. SARS-CoV-2 fluorescent microsphere immunochromatographic test strips were prepared by the combination of time-resolved fluorescence immunoassay with a lateral flow assay. The analytical performance and clinical evaluation of this testing method was done and the clinical significance of the testing method was verified. The LLOD of SARS-CoV-2 antibody IgG and IgM was 0.121U/L and 0.366U/L. The specificity of IgM and IgG strips in healthy people and in patients with non-COVID-19 disease was 94%, 96.72% and 95.50%, 99.49%, respectively; and sensitivity of IgM and IgG strips for patients during treatment and follow-up was 63.02%, 37.61% and 87.28%, 90.17%, respectively. The SARS-CoV-2 antibody test strip can provide rapid, flexible and accurate testing, and is able to meet the clinical requirement for rapid on-site testing of virus. The ability to detect IgM and IgG provided a significant benefit for the detection and prediction of clinical course with COVID-19 patients.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA