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1.
Anal Chem ; 2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33656332

RESUMO

In vitro noncontact cell-based coculture models are frequently employed to study cell-to-cell communication. However, these models cannot accurately represent the complexity of in vivo signaling. d-Lactate is an unusual metabolite produced and released by cancer cells. The characterization of d-lactate is challenging as it shares the same mass but has much lower amounts compared with l-lactate. Herein, d-α-hydroxy acids were specifically recognized and dehydrogenated by d-α-hydroxy acid dehydrogenase. The dehydrogenation products were rapidly quaternized for enhancement of mass signals. An on-probe enzymatic dehydrogenation-derivatization method was proposed for chiral analysis of α-hydroxy acids at the single-cell level. It is a promising amplification methodology and affords over 3 orders of magnitude signal enhancement. Furthermore, direct contact coculture models were used to precisely mimic the tumor microenvironment and explore the communication between cancer and normal cells. Single-cell mass spectrometry (SCMS) was further applied to easily sample cell extracts and study the differences of the aspects of small molecule metabolism in cocultured cells. On the basis of direct contact coculture SCMS, several differential small molecule metabolites and differences of oxidative stress between cocultured and monocultured normal cells were successfully detected. Additionally, d-lactate was discovered as a valuable differential metabolite with application of the two developed methods. It may account for the cancer-associated metabolic behavior of normal cells. These changes could be relieved after d-lactate metabolism-related drug treatment. This discovery may promote the investigation of d-lactate metabolism, which may provide a novel direction for cancer therapy.

2.
Surg Endosc ; 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33650005

RESUMO

BACKGROUND: Previous upper abdominal surgery (PUAS) is considered a contraindication to laparoscopic surgery. Whether LCBDE-PC is feasible and beneficial for patients with PUAS remains unclear. This study aimed to evaluate the feasibility and benefits of LCBDE-PC for patients with PUAS. METHODS: From June 2011 to September 2019, 1167 patients who underwent laparoscopic procedures for choledocholithiasis were reviewed retrospectively. Perioperative outcomes were compared between patients with and without PUAS in un-matched and matched cohorts. RESULTS: LCBDE-PC was performed successfully in 88.3% of patients with PUAS, and 92.5% of patients without PUAS (P > 0.05). Multivariate analysis showed that PUAS was not a risk factor that affected successful performance of LCBDE-PC. Although a higher rate of conversion to open surgery and longer operative time were observed in patients with PUAS, no significant differences were found between patients with and without PUAS in multivariate and propensity score analysis (P > 0.05). A predictive nomogram for LCBDE-PC failure was developed based on potential predictors from the least absolute shrinkage and selection operator (LASSO) regression model. Successful performance of LCBDE-PC was associated with operative time. A linear regression model for operative time showed impacted stone in the CBD and intraoperative laser use was the most important factor in determining the operative time. CONCLUSION: LCBDE-PC is feasible and beneficial for patients with PUAS. However, patients with PUAS with a high possibility of LCBDE-PC failure from the nomogram and a longer operative time from the linear regression model should be cautious when undergoing LCBDE-PC.

3.
J Biomol Struct Dyn ; : 1-12, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33645467

RESUMO

Hydroxylated polychlorinated biphenyls (HO-PCBs), as the major metabolites of PCBs, have been reported to act as estrogen receptor ß (ERß) agonists. However, the chemical-biological interactions governing their activities toward ERß have not been elucidated. Therefore, three dimensional quantitative structure-activity relationship (3D-QSAR), molecular docking and molecular dynamics (MD) simulations, to the best of our knowledge, for the first time were performed to explore the correlation between the structures and activities. The best 3D-QSAR model presented higher predictive ability (R2cv=0.543, R2pred=0.5793/R2cv=0.543, R2pred=0.6795) based on comparative molecular field analysis (CoMFA) and comparative similarity indices analysis (CoMSIA), respectively. At the same time, the derived contour maps indicated the important structural features required for improving the activity. Furthermore, molecular docking studies and MD simulations predicted the binding mode and the interactions between the ligand and the receptor. All the results would lead to a better understanding of the specific mechanism of HO-PCBs on estrogen receptor ß (ERß).Communicated by Ramaswamy H. Sarma.

4.
Nanoscale ; 2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33634799

RESUMO

Photon upconversion is a fascinating phenomenon that can convert low-energy photons to high-energy photons efficiently. However, most previous relevant research has been focused on upconversion systems with a sufficiently low lanthanide emitter concentration, such as 2 mol% for Er3+ in an Er-Yb coupled system. Realizing the upconversion from lanthanide heavily doped systems in particular, the emitter sublattice is still a challenge. Here, we report a mechanistic strategy to achieve the intense upconversion of the holmium sublattice in a core-shell-based nanostructure design through interfacial energy transfer channels. This design allowed a spatial separation of Ho3+ and sensitizers (e.g., Yb3+) into different regions and unwanted back energy transfers between them could then be minimized. By taking advantage of the dual roles of Yb3+ as both a migrator and energy trapper, a gradual color change from red to yellowish green was achievable upon 808 nm excitation, which could be further markedly enhanced by surface attaching indocyanine green dyes to facilitate the harvesting of the incident excitation energy. Moreover, emission colors could be tuned by applying non-steady state excitation. Such a fine-tunable color behavior holds great promise in anti-counterfeiting. Our results present a facile but effective conceptual model for the upconversion of the holmuim sublattice, which is helpful for the development of a new class of luminescent materials toward frontier applications.

5.
Proc Natl Acad Sci U S A ; 118(8)2021 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-33558418

RESUMO

The expansion of anatomically modern humans (AMHs) from Africa around 65,000 to 45,000 y ago (ca. 65 to 45 ka) led to the establishment of present-day non-African populations. Some paleoanthropologists have argued that fossil discoveries from Huanglong, Zhiren, Luna, and Fuyan caves in southern China indicate one or more prior dispersals, perhaps as early as ca. 120 ka. We investigated the age of the human remains from three of these localities and two additional early AMH sites (Yangjiapo and Sanyou caves, Hubei) by combining ancient DNA (aDNA) analysis with a multimethod geological dating strategy. Although U-Th dating of capping flowstones suggested they lie within the range ca. 168 to 70 ka, analyses of aDNA and direct AMS 14C dating on human teeth from Fuyan and Yangjiapo caves showed they derive from the Holocene. OSL dating of sediments and AMS 14C analysis of mammal teeth and charcoal also demonstrated major discrepancies from the flowstone ages; the difference between them being an order of magnitude or more at most of these localities. Our work highlights the surprisingly complex depositional history recorded at these subtropical caves which involved one or more episodes of erosion and redeposition or intrusion as recently as the late Holocene. In light of our findings, the first appearance datum for AMHs in southern China should probably lie within the timeframe set by molecular data of ca. 50 to 45 ka.

6.
Artigo em Inglês | MEDLINE | ID: mdl-33606493

RESUMO

The formation of zigzags, chevrons, Y-junctions, and line segments is demonstrated in thin films formed from cylindrical morphology silicon-containing conformationally asymmetric rod-coil diblock copolymers and triblock terpolymers under solvent annealing. Directed self-assembly of the block copolymers within trenches yields well-ordered cylindrical microdomains oriented either parallel or transverse to the sidewalls depending on the chemical functionalization of the sidewalls, and the location and structure of concentric bends in the cylinders is determined by the shape of the trenches. The innate etching contrast, the spontaneous sharp bends and junctions, and the range of demonstrated periodicity and line/space ratios make these conformationally asymmetric rod-coil polymers attractive for nanoscale pattern generation.

7.
Plant Dis ; 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33543992

RESUMO

Cucumis metuliferus, also called horned cucumber or jelly melon, is considered as a wild species in the Cucumis genus and a potential material for nematodes- or viruses-resistant breeding (Provvidenti, et al. 1977; Sigüenza et al. 2005; Chen et al. 2020). This species, originating from Africa, has been cultivated as a fruit in China in recent years. In July 2020, a mosaic disease was observed on C. metuliferus growing in five fields (approximately 0.7 hectare) in Urumqi, Xijiang, China, where more than 85~100% of the field plants exhibited moderate to severe viral disease-like leaf mosaic and/or deformation symptoms. Delayed flowering and small and/or deformed fruits on the affected plants could result in yield loss of about 50%. To identify the causal pathogen, the symptomatic leaf samples were collected from the five fields (five plants/points for each field) and their total RNAs were extracted using a commercial RNA extraction kit. The universal potyviral primers (Ha et al. 2008) and specific primers for a number of frequently-occurring, cucurbit crop-infecting viruses including Papaya ringspot virus (PRSV) (Lin et al. 2013), Cucumber mosaic virus (CMV) and Watermelon mosaic virus (WMV) were designed and used for detection by RT-PCR. The result showed that only the WMV primers (forward: 5'-AAGTGTGACCAAGCTTGGACTGCA-3' and reverse: 5'-CTCACCCATTGTGCCAAAGAACGT-3') could amplify the corresponding target fragment from the total RNA templates, and direct sequencing of the RT-PCR products and GenBank BLAST confirmed the presence of WMV (genus Potyvirus) in the collected C. metuliferus samples. To complete Koch's postulates, the infected C. metuliferus leaves were ground in the sodium phosphate buffer (0.01 M, pH 7.0) and the sap was mechanically inoculated onto 30 four-leaf-stage C. metuliferus seedlings (two leaves for each seedling were inoculated) kept in an insect-proof, temperature-controlled greenhouse at 25~28℃. Twenty-five of the inoculated plants were observed to have apparent leaf mosaic similar to the field symptoms two weeks after inoculation, and positive result was obtained in RT-PCR detection for the symptomatic leaves of inoculated plants using the WMV primers aforementioned, confirming the virus as the pathogen of C. metuliferus in Urumqi. To our knowledge, this is the first report of WMV naturally infecting C. metuliferus in China. We obtained the full-length sequence of the WMV Urumqi isolation (WMV-Urumqi) by sequencing the RT-PCR amplicons from seven pairs of primers spanning the viral genome and the 5'RACE and 3'RACE products. The complete sequence of WMV-Urumqi (GenBank accession no. MW345911) is 10046 nucleotides (nt) long and contains an open reading frame that encodes a polyprotein of 3220 amino acids (aa). WMV-Urumqi shares the highest nt identity (95.9%) and aa identity (98.0%) with the Cucurbita pepo-infecting isolation (KX664483) from Shanxi province, China. Our findings provide a better understanding of the host range and genetic diversity of WMV, and a useful reference for virus-resistant breeding involving C. metuliferus.

8.
BMC Surg ; 21(1): 81, 2021 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-33579250

RESUMO

BACKGROUND: The prognostic value of external vs internal pancreatic duct stents after pancreaticoduodenectomy remains controversial. This study aimed to evaluate the benefits of external and internal stents using the Fistula Risk Score system with regard to the incidence of clinically relevant postoperative pancreatic fistula. METHODS: A total of 382 patients who underwent pancreaticoduodenectomy with duct to mucosa pancreaticojejunostomy were retrospectively enrolled from January 2015 to October 2019. The receiver operating characteristic curve was performed for subgroup analysis of the patients at different levels of risk for pancreatic fistula. RESULTS: There were no significant differences in terms of pancreatic fistula or other postoperative complications. According to the receiver operating characteristic curve threshold of 3.5, 172 patients with a Fistula Risk Score ≥ 4 and 210 patients with a Fistula Risk Score < 4 were divided into separate groups. The number of valid cases was insufficient to support the subsequent research in patients with a Fistula Risk Score < 4. In patients with a Fistula Risk Score ≥ 4, the use of an external pancreatic duct stent was significantly more effective than the use of an internal stent, especially with regard to the risk for pancreatic fistula (Grade C) (P = 0.039), at ameliorating the incidence of clinically relevant postoperative pancreatic fistula (P = 0.019). Additionally, the incidence of lymphatic leakage was significantly higher in the external stent group compared with the internal stent group (P = 0.040). CONCLUSIONS: Compared with internal stents, the use of an external stent could reduce the incidence of clinically relevant postoperative pancreatic fistula in patients with a Fistula Risk Score ≥ 4. More large-scale prospective clinical trials are warranted to further clarify our results.


Assuntos
Ductos Pancreáticos/cirurgia , Fístula Pancreática/prevenção & controle , Pancreaticoduodenectomia/métodos , Pancreaticojejunostomia/métodos , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fístula Pancreática/epidemiologia , Fístula Pancreática/etiologia , Pancreaticoduodenectomia/efeitos adversos , Complicações Pós-Operatórias/epidemiologia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Stents , Resultado do Tratamento
9.
Surg Endosc ; 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33619595

RESUMO

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) has gained wide popularity for the treatment of choledocholithiasis. However, it remains unclear whether LCBDE is a better alternative option for the patients with difficult biliary stones. Thus, the aim of the present study was to explore the safety and efficacy of LCBDE for these patients by retrospectively analyzing our data and combing with literature review. METHODS: Between September 2011 and February 2019, 1064 consecutive patients who underwent LCBDE at Shanghai Tenth People's Hospital were reviewed. The clinical data of patients with difficult biliary stones were selected and retrospectively analyzed. RESULTS: Of these patients, 334 cases were confirmed with difficult biliary stones, and the overall complete stone clearance rate was 98.8% (330/334). 34 cases (10.2%) were performed with laser lithotripsy. A total of 296 patients (88.6%) underwent primary closure of common bile duct, and T-tube drainage was indwelled in 38 patients (11.4%). No bile duct injury, bleeding, perforation and surgery-related deaths were observed. The overall morbidity rate was 6.6%. 16 cases (4.8%) occurred in bile leakage with primary closure procedure, and all of them were managed successfully with conservative therapy. The median follow-up period was 9 months with stone recurrence occurring in 9 patients (2.7%). There was no evidence of bile duct stricture in all cases. CONCLUSIONS: The current study suggests that LCBED is a considerable safe and effective option for the patients with difficult biliary stones. A randomized clinical trial is needed to further evaluate the benefit of LCBDE in this subgroup.

10.
Artigo em Inglês | MEDLINE | ID: mdl-33606057

RESUMO

Fluorine (F) in water has a negative effect on the environment and human health. Schwertmannite has potential remediation to contamination in solution. In this study, the adsorption mechanism and influencing factors of synthetic schwertmannite for low-concentration F were studied through batch experiments. The results suggested that the adsorption of F by schwertmannite reached equilibrium after about 60 min, and the adsorption efficiency exceeded 94%. The experimental data can be best-fit by the pseudo-second-order kinetic and Langmuir models well. Schwertmannite showed effective adsorption at pH 4, dosage 1.5 g L-1, low temperature, and low concentration of co-existing anion. The adsorption process was a spontaneous and exothermic reaction, which was dominated by chemical adsorption. FT-IR and XPS spectra analysis revealed that F adsorption on schwertmannite through the surface complexation and anion exchange reaction between SO42- and OH- with F-, especially the primary role of OH-. The results can provide theoretical support for the schwertmannite application in the treatment of F-containing wastewater.

11.
Phys Chem Chem Phys ; 23(7): 4187-4194, 2021 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-33586748

RESUMO

Double-layered V2O5 and its analogues have received increasing attention as a proper cathode for Mg2+, Na+, Li+ ion batteries, even for ammonium ion batteries. Our theoretical research focuses on the effects of NH4+ ions on the structural stability and the ion diffusion properties of double-layered V2O5. The elastic constant calculations indicate the NH4+ and water contents have a dramatic influence on the stability of the electrode. When the ratio of H2O and ammonia ions decreases to (NH4)0.125V2O5·0.125H2O, double-layered bronze will transform into other phases. The predicted specific capacity for the redox process from (NH4)0.5V2O5·0.5H2O to (NH4)0.125V2O5·0.125H2O is 54.6 mA h g-1, which agrees with the experimental value of 55.6 mA h g-1. From the diffusion barrier calculations, it is found that the H2O molecules can shield the polarization of NH4+ and lower the diffusion barrier of NH4+ ions. Furthermore, the migrations of common charge carriers in NH4+ pre-intercalated V2O5 have also been studied, which implies that Li+, Zn2+, Na+, Mg2+ ions may move easily in the electrode with energy barriers lower than 525 meV. Our findings match well with the reported experimental results. A special structure of Mg6NH4V8O20 with a much higher Mg ion concentration has been reported. Our findings show that the theoretical specific density of Mg batteries based on NH4+ pre-intercalated V2O5 can be improved to 431 mA h g-1, which is 2.5 times larger than the reported values. This work highlights the effects of the ratio of NH4+ and H2O on double-layered V2O5 and provides insights into designing vanadium oxide based fast-diffusion multivalent ion conductors, which are suitable for battery applications.

12.
AIDS Care ; : 1-7, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33525906

RESUMO

Little is known about pre-exposure prophylaxis (PrEP) awareness and willingness among male rural-to-urban migrant workers, a high-risk population of HIV infection and transmission in China. The aim of this study was to assess the awareness of and willingness to use PrEP among this vulnerable population in two cities in Guangxi Zhuang autonomous region, a province in southwestern China. A cross-sectional survey was conducted among male rural-to-urban migrant workers in Guangxi province, during June to August, 2015. Multivariable logistic regression analysis was used to examine the factors related to PrEP acceptance. Among 669 male rural-to-urban migrant workers surveyed, the HIV prevalence was 1.79%. Among the 657 HIV-negative participants, 23.0% had heard of PrEP, 1.2% had used PrEP, and 64.7% were willing to use PrEP. Being afraid of HIV/AIDS (OR = 2.08, 95%CI: 1.04-4.19) and willing to have an HIV test (OR = 3.74, 95%CI: 1.64-8.52) were associated with willingness to use PrEP. The findings suggest that among male migrant workers in Southwestern China, the awareness of and willingness to use PrEP were relatively low. Given the fact that the HIV prevalence was high among this population, more educational campaigns about PrEP and targeted interventions are necessary for this high-risk population in Guangxi.

13.
Cancer Res ; 2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33402390

RESUMO

Although obesity is one of the strongest risk factors for esophageal adenocarcinoma (EAC), the molecular mechanisms underlying this association remain unclear. We recently identified 4 EAC-specific master regulator transcription factors (MRTF) ELF3, KLF5, GATA6, and EHF. In the present study, Gene Set Enrichment Analysis (GSEA) of both EAC patient samples and cell line models unbiasedly underscore fatty acid synthesis as the central pathway downstream of three MRTF (ELF3, KLF5, GATA6). Further characterizations unexpectedly identified a transcriptional feedback loop between MRTF and fatty acid synthesis, which mutually activated each other through the nuclear receptor PPARG. MRTF cooperatively promoted PPARG transcription by directly regulating its promoter and a distal EAC-specific enhancer, leading to PPARG overexpression in EAC. PPARG was also elevated in Barrett's esophagus, a recognized precursor to EAC, implying that PPARG might play a role in the intestinal metaplasia of esophageal squamous epithelium. Upregulation of PPARG increased de novo synthesis of fatty acids, phospholipids, and sphingolipids as revealed by mass spectrometry-based lipidomics. Moreover, ChIP-Seq, 4C-Seq, and a high-fat diet murine model together characterized a novel, noncanonical, and cancer-specific function of PPARG in EAC. PPARG directly regulated the ELF3 super-enhancer, subsequently activating the transcription of other MRTF through an interconnected regulatory circuitry. Together, elucidation of this novel transcriptional feedback loop of MRTF/PPARG/fatty acid synthesis advances our understanding of the mechanistic foundation for epigenomic dysregulation and metabolic alterations in EAC. More importantly, this work identifies a potential avenue for prevention and early intervention of EAC by blocking this feedback loop.

14.
Anal Chem ; 93(4): 2385-2393, 2021 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-33439630

RESUMO

This work highlights the use of push-pull hydroxylphenylpolyenylpyridinium fluorophores coupled with trimethyl lock quinone to engineer the ratiometric two-photon probes for cellular and intravital imaging of mitochondrial NAD(P)H:quinone oxidoreductase 1 (NQO1), a critical antioxidant enzyme responsible for detoxifying quinones. As a typical representative, QBMP showed favorable binding with NQO1 with a Michaelis constant of 12.74 µM and exhibited a suite of superior properties, including rapid response (4 min), large Stokes shift (162 nm), ultralow detection limit (0.9 nM), favorable two-photon cross section for the released fluorophore (70.5 GM), and deep tissue penetration (225 µm) in fixed brain tissues. More importantly, this probe was successfully applied for distinguishing different NQO1-expressing cancer and normal cells, revealing decreased NQO1 activity in a cellular Parkinson's disease model, screening NQO1 inducers as neuroprotective agents, and imaging of NQO1 in live mouse brain.

15.
Bull Environ Contam Toxicol ; 106(1): 134-145, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33392691

RESUMO

To explore the adsorption removal mechanism of Mg-Al layered double oxides (LDOs) for low-concentration (≤ 5 mg L-1) Cr(VI), the adsorption kinetics, adsorption isotherms and its influencing factors were studied by batch experiments. Cr(VI) adsorption reached equilibrium after 6, 11 and 15 h for initial Cr(VI) concentrations of 1, 3 and 5 mg L-1, respectively, and the final adsorption efficiency exceeded 99.0%. The residual concentration of Cr(VI) was within the allowable limit of Drinking Water Quality Standard of World Health Organization (0.05 mg L-1). The experimental data fitted the pseudo-second-order and Freundlich models well. Mg-Al LDOs showed effective adsorption efficiency in the range of pH 3-9, and the adsorption efficiency was influenced by anions competition (HPO42- > SO42- > CO32- > NO3- > Cl-). The analyses of XRD, SEM and FT-IR spectra suggested adsorption Cr(VI) on Mg-Al LDOs was caused by capturing dichromate ions to reconstruct its structure. Therefore, Mg-Al LDOs is promising adsorbents for the low-concentration Cr(VI) treatment in polluted surface water and groundwater.


Assuntos
Óxidos , Poluentes Químicos da Água , Adsorção , Cromo/análise , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
16.
Nat Neurosci ; 24(2): 186-196, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33432196

RESUMO

Retrotransposons can cause somatic genome variation in the human nervous system, which is hypothesized to have relevance to brain development and neuropsychiatric disease. However, the detection of individual somatic mobile element insertions presents a difficult signal-to-noise problem. Using a machine-learning method (RetroSom) and deep whole-genome sequencing, we analyzed L1 and Alu retrotransposition in sorted neurons and glia from human brains. We characterized two brain-specific L1 insertions in neurons and glia from a donor with schizophrenia. There was anatomical distribution of the L1 insertions in neurons and glia across both hemispheres, indicating retrotransposition occurred during early embryogenesis. Both insertions were within the introns of genes (CNNM2 and FRMD4A) inside genomic loci associated with neuropsychiatric disorders. Proof-of-principle experiments revealed these L1 insertions significantly reduced gene expression. These results demonstrate that RetroSom has broad applications for studies of brain development and may provide insight into the possible pathological effects of somatic retrotransposition.

17.
Plant Dis ; 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33507099

RESUMO

Three of the cereal cyst nematodes, Heterodera avenae, H. filipjevi and H. latipons are considered to be the most economically important cyst nematodes that affect cultivated cereals around the world. H. filipjevi was first detected in China from Xuchang, Henan Province in 2010 (Peng et al. 2010) and now has been recorded in the Central China of Henan, Shandong and Anhui provinces and the Northwest China of Xinjiang Uygur Autonomous Region (Cui et al. 2020). In June 2019, 42 samples consisting of roots and soil were collected from winter wheat fields in Hebei Province of North China. Cysts were detected in 37 soil samples with a mean of 6.4 ± 1.67 cysts per 100 ml of soil. Cysts and second-stage juveniles (J2s) were extracted from root and soil following Cobb's sieving gravity method. Morphological and molecular studies of J2s and cysts confirmed its identity with H. filipjevi in 5 samples from Handan (N36°10'052" and E114°35'056"; N36°37'054" and E114°22'052"), Xingtai (N36°53'060" and E114°30'011") and Shijiazhuang (N 37°26'048" and E 116°05'039") in Hebei Province, China. Morphologically, the cysts are lemon-shaped, light or dark brown in color. The vulval cone is bifenestrate with horseshoe-shaped semifenestrae, strongly globular bullae, and well-developed underbridge. Measurements (mean +_ sd (range)) of cysts (n=10), body length not including neck is 743.0 ± 36.1 µm (665 - 780 µm), body width is 559.0 ± 50.0 µm (455 - 639 µm), length / width ratio is 1.33 ± 0.07 (1.20 - 1.46); neck length is 99.3 ± 8.8 µm (85 - 122 µm); fenestrae length is 56.8 ± 5.0 µm (49 - 65 µm) and width is 25.5 ± 1.8 µm (21.1 - 27.8 µm); underbridge length is 84.0 ± 8.1 µm (62 - 93 µm); and vulval slit length is 8.6 ± 0.5 µm (7.2 - 9.1 µm). Measurements of J2s (n = 12), body length is 541 ± 11.4 µm (490 - 578 µm); stylet length is 22.3 ± 0.5 µm (22.0 - 25.0 µm) with anchor-shaped basal knobs; tail length is 57.7 ± 3.7 µm (52.7 - 65.2 µm), and hyaline tail terminal length is 36.5 ± 2.8 µm (32 - 39.8 µm). The tail had a sharp terminus. Morphology of the cysts and J2s were consistent with the record of H. filipjevi (Peng et al. 2010; Subbotin et al. 2010). The amplifications of rDNA-internal transcribed spacer (ITS) fragments were generated with a PCR fragment of 1054 bp from single cysts of each population, using primers TW81 and AB28 (Joyce et al. 1994). The PCR tests for each sample were repeated five times. The PCR product was purified and sequenced. All nucleotide sequences of ITS-rDNA were submitted to GenBank under accession numbers MW282843-6. Sequences from the ITS region were more than 99.5% identical to those of H. filipjevi from Egypt (KF225725), Turkey (KR704308, KR704293 and MN848333) and China (KT314234, MT254744 and KY448473). These results from ITS supported its identity as H. filipjevi. The results were also confirmed by species specific sequence characterized amplified region primers of H. filipjevi (Peng et al. 2013). Pathogenicity of the H. filipjevi was confirmed by infection of winter wheat (Triticum aestivum L cv. 'Aikang58') and examination of the nematode development and reproduction. Wheat seeds were germinated in petri dishes and then transplanted into five polyvinyl chloride tubs (3 cm in diameter, 25 cm in length) that contained 150 cm3 of a sterile soil mixture (loamy soil: sand = 1:1), each with 5 cysts (mean of 252.0 eggs/cyst). Plants were grown in an artificial climate box for one week at 14/18°C, two weeks at 16/20°C, five weeks at 18/25°C and two weeks at 22/30°C, under 8 h of darkness/16 h light and normal culturing practices (Cui et al. 2015). The parasitic J2s, third and fourth-stage juveniles, and adult females were observed in roots stained with acid fuchsin at 10, 20, 30, and 50 days after inoculation (DAI), and an average of 32.0 cysts per tubes were extracted 70 DAI. The new cyst' morphological and molecular characteristics were identical to the H. filipjevi cysts from the original soil samples. Three other tubes without cysts were set as control and there were no newly formed cysts. Heterodera avenae and H. filipjevi had been detected in a total of 16 wheat-producing provinces in China, which resulted in losses of 1.9 billion CNY year-1 (Cui et al. 2015). To our knowledge, this is the first report of H. filipjevi in Hebei Province of North China. Cereal cyst nematodes are easily transferred to non-infested areas by many avenues, resulting in increased species and pathotype complexity (Cui et al. 2020). Once H. filipjevi continues to spread in main wheat producing area of China, it could become be a new threat to cereals production. It is time to take effective control methods to prevent H. filipjevi further dispersal, especially through the farming machinery transmission. Hebei Province is one of the most important major grain-producing areas, our findings will be very beneficial for H. filipjevi management and further research on winter wheat in Hebei Province, North China.

18.
J Hazard Mater ; 401: 123265, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-32629347

RESUMO

Reusing biogas slurry (BS) in agricultural drip irrigation systems may provide a solution to deal with the adverse environmental impacts of applying BS. Biofouling and scaling are two leading issues in drip irrigation emitters. This study investigated a practice that applied electromagnetic fields (EMFs) to control biofilms and scales. The bacterial communities and mineral precipitations in the clogging substances of emitters were determined. Results showed that EMFs inhibited the growth of microbes, and influenced BS physicochemical parameters. Consequently, EMFs shifted the bacterial communities with reduced diversities. Network analyses revealed that bacterial species under EMFs treatments showed lower average connectivities and simpler interactions, which were responsible for the decreases of extracellular polymers substances (EPS). Moreover, EMFs treatments not only reduced the carbonates in emitters, but also prevented the depositions of phosphates, silicates, and quartzes. EMFs also had impacts on the lattice parameters and crystal volumes of carbonates. In addition, the changes in bacterial communities and EPS contents were associated with the reductions of various minerals. Accordingly, EMFs effectively mitigated biofilms and scales with the fixed clogging substances reduced by 29.1-53.8 %. These findings demonstrated that applying EMFs is an effective anti-biofouling and anti-scaling treatment with potential applications in BS irrigation systems.

19.
Cancer Lett ; 497: 89-99, 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33038492

RESUMO

The human genome contains thousands of noncoding RNAs (ncRNAs), which are thought to lack open reading frames (ORFs) and cannot be translated. Some ncRNAs reportedly have important functions, including epigenetic regulation, chromatin remolding, protein modification, and RNA degradation, but the functions of most ncRNAs remain elusive. Through the application and development of ribosome profiling and sequencing technologies, an increasing number of studies have discovered the translation of ncRNAs. Although ncRNAs were initially defined as noncoding RNAs, a number of ncRNAs actually contain ORFs that are translated into peptides. Here, we summarize the available methods, tools, and databases for identifying and validating ncRNA-encoded peptides/proteins, and the recent findings regarding ncRNA-encoded small peptides/proteins in cancer are compiled and synthesized. Importantly, the role of ncRNA-encoding peptides/proteins has application prospects in cancer research, but some potential challenges remain unresolved. The aim of this review is to provide a theoretical basis that might promote the discovery of more peptides/proteins encoded by ncRNAs and aid the further development of novel diagnostic and prognostic cancer markers and therapeutic targets.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 248: 119264, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33310274

RESUMO

Hydrogen peroxide (H2O2), depending on its levels, plays a crucial role in either modulating various biological processes as a signal molecule, or mediating oxidative damage as a toxin. Therefore, monitoring intracellular H2O2 levels is pivotal for exploring its physiological and pathological roles. Using a modified 2-(2'-hydroxyphenyl) benzothiazole (HBT) as the fluorophore, and a pinacol phenylborate ester as the responsive group, herein we developed an excited-state intramolecular proton transfer (ESIPT)-based probe BTFMB. The probe exhibited turn-on fluorescence response, large Stokes shift (162 nm) and low detection limit (109 nM) toward H2O2, and was successfully applied for monitoring exogenous and endogenous production of H2O2, and identifying accumulation of H2O2 during the ferroptosis process.

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