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1.
Proc Natl Acad Sci U S A ; 119(51): e2211193119, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36520670

RESUMEN

An interplay of geometrical frustration and strong quantum fluctuations in a spin-1/2 triangular-lattice antiferromagnet (TAF) can lead to exotic quantum states. Here, we report the neutron-scattering, magnetization, specific heat, and magnetocaloric studies of the recently discovered spin-1/2 TAF Na2BaCo(PO4)2, which can be described by a spin-1/2 easy axis XXZ model. The zero-field neutron diffraction experiment reveals an incommensurate antiferromagnetic ground state with a significantly reduced ordered moment of about 0.54(2) µB/Co. Different magnetic phase diagrams with magnetic fields in the ab plane and along the easy c-axis were extracted based on the magnetic susceptibility, specific heat, and elastic neutron-scattering results. In addition, two-dimensional (2D) spin dispersion in the triangular plane was observed in the high-field polarized state, and microscopic exchange parameters of the spin Hamiltonian have been determined through the linear spin wave theory. Consistently, quantum critical behaviors with the universality class of d = 2 and νz = 1 were established in the vicinity of the saturation field, where a Bose-Einstein condensation (BEC) of diluted magnons occurs. The newly discovered quantum criticality and fractional magnetization phase in this ideal spin-1/2 TAF present exciting opportunities for exploring exotic quantum phenomena.

2.
Anal Chem ; 2024 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-39263911

RESUMEN

Eu isotopes are promising tracers across various scientific domains such as planetary, earth, and marine science, yet their high-precision analysis has been challenging due to the similar geochemical properties of rare earth elements (REEs). In this study, a novel two-column chromatographic approach was developed utilizing AG50W-X12 and TODGA resins to separate Eu effectively from matrix and interfering elements like Ba, Nd, Sm, and Gd, while ensuring high Eu yields (99.4 ± 0.4%, n = 19) and low blanks (<20 pg). The robustness of this method is evidenced by various rock types and different Eu loading masses. The efficient purification of Eu facilitated the establishment of a high-precision calibration technique with standard-sample bracketing (SSB) and internal normalization (Nd). When a Nu Plasma 1700 multicollector-inductively coupled plasma-mass spectrometry (MC-ICP-MS) instrument was employed, repeated purification and analysis of various Geological Reference Materials (GRMs) confirmed that the long-term external precision of δ153/151Eu is better than 0.04‰ (2 standard deviation (2SD)), which represents a 2-5-fold increase in precision compared to previously reported methods. Additionally, the high-precision Eu isotopic compositions of five GRMs, including basalts, andesite, syenite, and marine sediment, were measured. The high-precision Eu isotope techniques presented herein open up new avenues for Eu isotope geochemistry.

3.
Angew Chem Int Ed Engl ; : e202417357, 2024 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-39365280

RESUMEN

With the development of mechanophores, polymer mechanochemistry has emerged as a powerful tool for creating force-responsive materials with a variety of desired functions, ranging from color change to molecular release. However, it remains challenging to improve the efficiency of mechanochemical activation, especially for mechanophores embedded within polymer networks, which has profound implications for translating mechanochemical responses into materials-centered applications. The physical and chemical conditions under spatial confinement differ significantly from those in the surrounding bulk environment, offering opportunities to facilitate mechanochemical activation. In this Minireview, we discuss and summarize recent progress in polymer mechanochemistry within confined spaces including surfaces/interfaces, polymer assemblies, and other nanostructures, specifically focusing on the effects of spatial confinement on the enhancement of mechanophore activation. We envision that combining confinement effects with advances in molecular and materials engineering will further improve the activation efficiency, capitalizing more fully on the potential of mechanophores toward practical applications.

4.
Int J Cancer ; 152(1): 7-14, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-35362560

RESUMEN

We aimed to determine participation in low-dose computed tomography (LDCT) of individuals with a family history of common cancers in a population-based screening program to provide timely evidence in high-risk populations in China. The analysis was conducted using data from the Cancer Screening Program in Urban China (CanSPUC), which recruited 282 377 participants aged 40 to 74 years from eight cities in the Henan province. Using the CanSPUC risk score system, 55 428 participants were evaluated to have high risk for lung cancer and were recommended for LDCT. We calculated the overall and group-specific participation rates using family history of common cancers and compared differences in participation rates between different groups. Odds ratios (ORs) and 95% confidence intervals were derived by multivariable logistic regression. Of the 55 428 participants, 22 260 underwent LDCT (participation rate, 40.16%). Family history of lung, esophageal, stomach, liver and colorectal cancer was associated with increased participation in LDCT screening. The odds of participants with a family history of one, two, three and four or more cancer cases undergoing LDCT screening were 1.9, 2.7, 2.8 and 3.5 times, respectively, than those without a family history of cancer. Compared to those without a history of cancer, participation in LDCT gradually increased as the number of cancer cases in the family increased (P < .001). Our findings suggest that there is room for improvement in lung cancer screening given the relatively low participation rate. Lung cancer screening in populations with a family history of cancer may improve efficiency and cost-effectiveness; however, this requires further verification.


Asunto(s)
Detección Precoz del Cáncer , Neoplasias Pulmonares , Humanos , Detección Precoz del Cáncer/métodos , Neoplasias Pulmonares/diagnóstico por imagen , Neoplasias Pulmonares/epidemiología , Tomografía Computarizada por Rayos X/métodos , Tamizaje Masivo , China/epidemiología
5.
Acta Radiol ; 64(5): 1943-1949, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36423247

RESUMEN

BACKGROUND: Satisfactory magnetic resonance imaging (MRI) of those patients with involuntary head motion due to brain diseases is essential in avoiding missed diagnosis and guiding treatment. PURPOSE: To investigate the clinical feasibility of artificial intelligence-assisted compressed sensing single-shot fluid-attenuated inversion recovery (ACS-SS-FLAIR) in evaluating patients with involuntary head motion due to brain diseases, compared with the conventional T2-FLAIR with parallel imaging (PI-FLAIR). MATERIAL AND METHODS: A total of 33 uncooperative patients with brain disease were prospectively enrolled. Two readers independently reviewed images acquired with ACS-SS-FLAIR and PI-FLAIR at a 3.0-T MR scanner. In the aspects of qualitative evaluation of image quality, overall image quality and lesion conspicuity of ACS-SS-FLAIR and PI-FLAIR were assessed and then statistically compared by paired Wilcoxon rank-sum test. For quantitative evaluation, the relative contrast of lesion-to-cerebral parenchyma were calculated and compared. RESULTS: Overall image quality scores of ACS-SS-FLAIR evaluated by two readers were 2.94 ± 0.24 and 2.91 ± 0.29, respectively, both of which were significantly higher than that of PI-FLAIR, respectively (P < 0.001 and <0.001). Lesion conspicuity scores of were 2.74 ± 0.47 and 2.79 ± 0.44, both of which were significantly higher than that of PI-FLAIR, respectively (P < 0.001 and <0.001). In the quantitative evaluation for image quality, the relative contrast of lesion-to-cerebral parenchyma was 0.34 ± 0.09 in the ACS-SS-FLAIR sequence, significantly larger than that in the PI-FLAIR sequence (P = 0.001). CONCLUSION: The ACS-SS-FLAIR sequence is clinically feasible in the MRI workup of those patients with involuntary head motion due to brain diseases, showing shorter image acquisition time and better image quality compared with conventional PI-FLAIR.


Asunto(s)
Inteligencia Artificial , Encefalopatías , Humanos , Estudios de Factibilidad , Imagen por Resonancia Magnética/métodos , Encefalopatías/diagnóstico por imagen , Encefalopatías/patología , Movimiento (Física) , Encéfalo/diagnóstico por imagen , Encéfalo/patología
6.
Pestic Biochem Physiol ; 197: 105695, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38072550

RESUMEN

Nuclear receptors play a crucial role in various signaling and metabolic pathways, such as insect molting and development. Buprofezin (2-tert-butylimino-3-isopropyl-5-phenyl-perhydro-1, 3, 5-thiadiazin-4-one), a chitin synthesis inhibitor, causes molting deformities and slow death in insects by inhibiting chitin synthesis and interfering with their metabolism. This study investigated whether buprofezin affects insect ecdysteroid signaling pathway. The treatment of buprofezin significantly suppressed the transcription levels of SfHR3 and SfHR4, two nuclear receptor genes, in third-instar nymphs of Sogatella furcifera. Meanwhile, the transcription levels of SfHR3 and SfHR4 in first-day fifth-instar nymphs were induced at 12 h after 20E treatment. In addition, the silencing of SfHR3 and SfHR4 genes in first-day fifth-instar nymphs caused severe developmental delay and molting failure, resulting in a significant reduction of survival rates at 7.36% and 2.99% on the eighth day, respectively. Further analysis showed that the silencing SfHR3 and SfHR4 significantly inhibited the transcription levels of chitin synthesis and degradation-related genes. These results indicate that buprofezin can inhibits chitin synthesis and degradation by suppressing the signal transduction of 20E through SfHR3 and SfHR4, leading to molting failure and death. This study not only expands our understanding of the molecular mechanism of buprofezin in pest control but also lays a foundation for developing new control strategies of RNAi by targeting SfHR3 and SfHR4.


Asunto(s)
Hemípteros , Muda , Animales , Muda/genética , Hemípteros/metabolismo , Insectos , Receptores Citoplasmáticos y Nucleares/metabolismo , Quitina/metabolismo , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo
7.
Pol J Pathol ; 74(2): 136-140, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36106424

RESUMEN

AIM OF THE STUDY: Aim of the study is To investigate the effect of lentinan on proliferation and apoptosis of human astrocytoma U251 cells. Lentinan was dissolved in DMEM complete medium to form different concentrations (0, 25, 50, 100, 200, 400, 500, 600 µg/ml). CCK8 was used to detect the effect of lentinan with different concentrations on proliferation of human astrocytoma U251 cells, and the expression of Ki-67 was detected by immunofluorescence. In addition, the effect of different concentrations of lentinan on apoptosis of human astrocytoma U251 cells was detected by flow cytometry. Compared with the blank control group, 50 and 100 µg/ml lentinan significantly promoted proliferation of human astrocytoma U251 cells. When the concentration is more than 100 µg/ml, the cell activity gradually decreases, and the cell activity is the lowest when the concentration is 600 µg/ml. In addition, the low concentration lentinan (25, 50, and 100 µg/ml) had no significant effect on apoptosis of human astrocytoma U251 cells. However, lentinan above 200 µg/ml significantly promoted apoptosis of human astrocytoma U251 cells and had a concentration gradient effect, and the highest apoptosis rate was at 600 µg/ml. CONCLUSIONS: Lentinan can effectively inhibit proliferation and promote apoptosis of human astrocytoma U251 cells.


Asunto(s)
Astrocitoma , Lentinano , Humanos , Lentinano/farmacología , Línea Celular Tumoral , Proliferación Celular , Apoptosis
8.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(1): 5-10, 2023 Jan 15.
Artículo en Zh | MEDLINE | ID: mdl-36655657

RESUMEN

OBJECTIVES: To study the clinical features of children with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant infection. METHODS: A retrospective analysis was performed on the medical data of 201 children with coronavirus disease 2019 (COVID-19) who were hospitalized and diagnosed with SARS-CoV-2 Omicron variant infection in Quanzhou First Hospital from March 14 to April 7, 2022. Among the 201 children, there were 34 children with asymptomatic infection and 167 with symptomatic infection. The two groups were compared in terms of clinical features, results of experimental examinations, and outcome. RESULTS: Of all the 201 children, 161 (80.1%) had a history of exposure to COVID-19 patients and 132 (65.7%) had a history of COVID-19 vaccination. Among the 167 children with symptomatic infections, 151 had mild COVID-19 and 16 had common COVID-19, with no severe infection or death. Among the 101 children who underwent chest CT examination, 16 had ground glass changes and 20 had nodular or linear opacities. The mean time to nucleic acid clearance was (14±4) days for the 201 children with Omicron variant infection, and the symptomatic infection group had a significantly longer time than the asymptomatic infection group [(15±4) days vs (11±4) days, P<0.05]. The group vaccinated with one or two doses of COVID-19 vaccine had a significantly higher positive rate of IgG than the group without vaccination (P<0.05). The proportions of children with increased blood lymphocyte count in the symptomatic infection group was significantly lower than that in the asymptomatic infection group (P<0.05). Compared with the asymptomatic infection group, the symptomatic infection group had significantly higher proportions of children with increased interleukin-6, increased fibrinogen, and increased D-dimer (P<0.05). CONCLUSIONS: Most of the children with Omicron variant infection have clinical symptoms, which are generally mild. The children with symptomatic infection are often accompanied by decreased or normal blood lymphocyte count and increased levels of interleukin-6, fibrinogen, and D-dimer, with a relatively long time to nucleic acid clearance. Some of them had ground glass changes on chest CT.


Asunto(s)
COVID-19 , Ácidos Nucleicos , Niño , Humanos , Infecciones Asintomáticas , COVID-19/diagnóstico , COVID-19/inmunología , COVID-19/virología , Vacunas contra la COVID-19 , Fibrinógeno , Interleucina-6 , Estudios Retrospectivos , SARS-CoV-2
9.
Small ; 18(24): e2201896, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35560706

RESUMEN

Reported herein is a highly active and durable hydrogen evolution reaction (HER) electrocatalyst, which is constructed following a tandem interface strategy and functional in alkaline and even neutral medium (pH ≈ 7). The ternary composite material, consisting of conductive nickel foam (NF) substrate, Ni3 S2 -MoS2 heterostructure, and TiO2 coating, is synthesized by the hydrothermal method and atomic layer deposition (ALD) technique. Representative results include: (1) versatile characterizations confirm the proposed composite structure and strong electronic interactions among comprised sulfide and oxide species; (2) the material outperforms commercial Pt/C by recording an overpotential of 115 mV and a Tafel slope of 67 mV dec-1 under neutral conditions. A long-term stability in alkaline electrolytes up to 200 h and impressive overall water splitting behavior (1.56 V @ 10 mA cm-2 ) are documented; (3) implementation of ALD oxide tandem layer is crucial to realize the design concept with superior HER performance by modulating a variety of heterointerface and intermediates electronic structure.

10.
Insect Mol Biol ; 31(6): 798-809, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35899838

RESUMEN

Sogatella furcifera is one of the most serious insect pests that affect rice in Asia. One class of small RNAs (sRNAs; ~22 nt long) is miRNAs, which participate in various biological processes by regulating the expression of target genes in a spatiotemporal manner. However, the role of miRNAs in nymph-to-adult transition in S. furcifera remains unknown. In this study, we sequenced sRNA libraries of S. furcifera prepared from individuals at three different developmental stages (pre-moult, moulting and early adult). A total of 253 miRNAs (134 known and 119 novel) were identified, of which 12 were differentially expressed during the nymph-to-adult developmental transition. Moreover, Real time quantitative PCR (RT-qPCR) analysis revealed that all 12 miRNAs were differentially expressed among five different nymph tissues and 14 different developmental stages (first to fifth instar nymphs and 1-day-old adults). Injection of miR-2a-2 mimic/antagomir and miR-305-5p-1 mimic/antagomir into 1-day-old fifth instar nymphs significantly increased the mortality rate. In addition, a defective moulting phenotype was observed in nymphs injected with miR-2a-2 and miR-305-5p-1, suggesting that these miRNAs are involved in S. furcifera nymph-adult transition. In conclusion, these results reveal the function of critical miRNAs in S. furcifera nymph-adult transition, and also provide novel potential targets of insecticides for the long-term sustainable management of S. furcifera.


Asunto(s)
Hemípteros , Insecticidas , MicroARNs , Animales , Ninfa/genética , Antagomirs , Hemípteros/genética
11.
Arch Insect Biochem Physiol ; 110(1): e21879, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35247285

RESUMEN

The Decapentaplegic gene controls wing patterning and spreading by regulating downstream genes in many insect species. However, the molecular characteristics, expression, and biological function of Dpp in Sogatella furcifera remain poorly understood. In this study, we cloned the Dpp gene from S. furcifera and examined its expression levels in different development stages, wing typed adults, and tissues. Then, the function of SfDpp gene was analyzed using an RNA interference (RNAi)-based approach. The results showed that the full-length complementary DNA  of the SfDpp gene consists of 1034 bp and contains a 954-bp open reading frame encoding 317 amino acids. SfDpp has a transforming growth factor-ß (TGF-ß) propeptide superfamily domain and a TGF-ß superfamily domain, typical of members of the TGF-ß superfamily. Quantitative real-time polymerase chain reaction showed that the expression of SfDpp reached its highest expression level 40 min after eclosion. RNAi-based gene silencing inhibited transcript levels of the corresponding messenger RNA in S. furcifera nymphs injected with double-stranded RNA of SfDpp and resulted in death of 29.17% and 26.67% of 4th and 5th instar nymphs, respectively. The wing deformity rate of the adults was 74.12% and 3.41% after SfDpp gene silencing in 4th and 5th instar nymphs, respectively. Examining wing development-associated genes showed that two target genes of Dpp (Vestigial and Spalt) were both dramatically downregulated after SfDpp was silenced. Our results demonstrate that downregulated SfDpp in early development causes wing expansion failure in S. furcifera. Thus, Dpp may be a target gene for restricting the migration of rice-damaging planthoppers.


Asunto(s)
Hemípteros , Animales , Hemípteros/genética , Metamorfosis Biológica , Ninfa/genética , Factor de Crecimiento Transformador beta , Alas de Animales
12.
Hepatobiliary Pancreat Dis Int ; 21(4): 370-377, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35778316

RESUMEN

BACKGROUND: ATP-binding cassette transporter G1 (ABCG1) regulates cellular cholesterol homeostasis and plays a significant role in tumor immunity. But, for hepatocellular carcinoma (HCC), the role of ABCG1 has not been investigated. Thus, the aim of this study was to evaluate the prognostic value and clinicopathological significance of ABCG1 in HCC. METHODS: One hundred and four adult patients with HCC were enrolled, and ABCG1 expression in paired HCC specimens was determined by immunohistochemistry. All these patients were stratified by ABCG1 expression, Kaplan-Meier analysis was used to compare the overall survival (OS) and recurrence-free survival (RFS), and Cox regression analysis was used to determine independent predictors of tumor recurrence. RESULTS: Upregulation of ABCG1 was observed in HCC samples compared to matched tumor-adjacent tissues. Patients with high nuclear ABCG1 expression had lower OS and RFS (P = 0.012 and P = 0.020, respectively). High nuclear ABCG1 expression was related to larger tumor size (P = 0.004) and tumor recurrence (P = 0.027). Although ABCG1 was expressed in the cytoplasm, cytosolic expression could not predict the outcome in patients with HCC. A new stratification pattern was established based on the heterogenous ABCG1 expression pattern: high risk (Highnucleus/Lowcytosol), moderate risk (Highnucleus/Highcytosol or Lownucleus/Lowcytosol), and low risk (Lownucleus/Highcytosol). This ABCG1-based risk stratification could distinguish the different OS and RFS in patients with HCC. Multivariate Cox regression analysis indicated that ABCG1 high risk was an independent predictor of poor RFS (P = 0.015). CONCLUSIONS: High nuclear ABCG1 expression indicates poor prognosis in patients with HCC. Asymmetric distribution of ABCG1 in the nucleus and cytoplasm may have an important role in tumor recurrence.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 1 , Adulto , Biomarcadores de Tumor/análisis , Carcinoma Hepatocelular/patología , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/patología , Recurrencia Local de Neoplasia , Pronóstico
13.
Pestic Biochem Physiol ; 173: 104779, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33771258

RESUMEN

The isoprene branching pathway is a unique downstream synthesis pathway of juvenile hormone (JH) in arthropods, which plays an important role in the growth, development, and reproduction of insects. Juvenile hormone acid O-methyltransferase (JHAMT) and farnesoic acid O-methyltransferase (FAMeT) are two key proteins that are regulated in the isoprene branching pathway. Based on the available transcriptomic and genomic data of Sogatella furcifera, full-length cDNAs of SfJHAMT and SfFAMeT were identified. In vitro injection of dsRNA targeted to silence SfJHAMT and SfFAMeT inhibited the fecundity, ovarian development, and transcription levels of SfKr-h1 and SfVg significantly. Of note, The transcription levels of SfJHAMT and SfFAMeT are regulated mutually; i.e., silencing of SfJHAMT causes an increase in the SfFAMeT transcription level and vice versa, and the negative effect of simultaneous silencing on reproduction is greater. The results revealed a coordinated effect of SfJHAMT and SfFAMeT on the reproductive capabilities of S. furcifera. Furthermore, a JH analog (methoprene) partially rescued the negative effect of simultaneous silencing by SfJHAMT and SfFAMeT on reproduction. In addition, the expression profile analysis after insecticide stress showed that triazophos (LC25) can induce the transcription of SfMet and SfKr-h1 to promote JH signal transduction, which affects the transcription of SfVg and ultimately promotes the reproduction of S. furcifera. The results of the present study lay a foundation to further explain the isoprene branch pathway function in insect reproduction and can open up new avenues for sustainable pest control while expanding the current understanding of molecular mechanisms through which insecticides stimulate reproduction and lead to pest resurgence.


Asunto(s)
Hemípteros , Insecticidas , Animales , Fertilidad , Insecticidas/toxicidad , Hormonas Juveniles , Reproducción
14.
Bioprocess Biosyst Eng ; 44(5): 995-1002, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33159544

RESUMEN

To study the difference in transcriptome level of fatty acid metabolism pathway in Bamei pork and the difference of pork quality caused by the difference. In this study, Bamei pigs breeding in Huzhu farm of QingHai province were selected as the test object, compared with Gansu Black pigs. Four indexes of nutmeg acid (DX1), palmitic acid (DX2), stearic acid (DX3) and linoleic acid (DX4) were set. The expression profiles of fat metabolism related genes between the two groups samples were analysed by GCMS metabolomics and transcriptomics, then coexpression network analysis were conducted to obtain phenotypic related genes. The results showed that the metabolic levels of DX3 and DX4 were significantly higher than those of other fatty acids. Among these differences, the ENSSSCG00000024681 (G1) and ENSSSCG00000036883 (G2) genes play important regulatory roles in fatty acid metabolism, and the upregulated expression of their gene obviously affects the level of fatty acid metabolism, thereby affecting the quality and taste of pork. In addition, we found that there was a good correlation between the same lines, and the genetic traits of the hybrid lines of Bamei pig and Black pig are more inclined to Bamei pig. In the independent fatty acid metabolism, "Mg2+"and flavin adenine dinucleotide are more active, which plays an important role in energy utilization. Therefore, we can be inferred that the metabolism of stearic acid and linoleic acid are important fatty acids for pork quality. It also further confirms that the research method of combined omics is of great significance for the study of species traits and gene functions.


Asunto(s)
Ácidos Grasos , Metabolismo de los Lípidos , Metaboloma , Carne de Cerdo , Transcriptoma , Animales , Especificidad de la Especie , Porcinos
15.
J Insect Sci ; 21(4)2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34333649

RESUMEN

Chitin deacetylases (CDAs) are chitin-degrading enzymes that play a key role in insect molting. In this study, we identified and characterized four full-length cDNAs of CDAs from Sogatella furcifera (Horváth). Developmental expression showed that SfCDA1 and SfCDA2 were expressed at all nymph developmental stages, SfCDA3 and SfCDA4 were mainly expressed in the third-instar to fifth-instar nymph stages, whereas tissue-specific analyses indicated that four CDA genes were mainly high expressed in the integument and head during the fifth-instar nymph. RNA interference (RNAi) results revealed that SfCDA1, SfCDA2, and SfCDA4 are associated with molting defect and high mortality with nymph-adult molting. Furthermore, transcripts of chitin synthase 1 variants (SfCHS1, SfCHS1a, and SfCHS1b) were significantly downregulated and causing significant changes in the expression levels of trehalases (TRE1 and TRE2) in the SfCDA1, SfCDA2, and SfCDA4 dsRNA treatment groups. By contrast, no significant phenotypic characteristics were observed after dsSfCDA3 injection. Taken together, our results suggest that SfCDA1, SfCDA2, and SfCDA4 play a vital role in nymph-adult transition, and these genes could regulate chitin biosynthesis expression levels.


Asunto(s)
Amidohidrolasas/genética , Hemípteros , Animales , Quitina/biosíntesis , Quitina/genética , ADN Complementario , Genes de Insecto , Hemípteros/genética , Proteínas de Insectos/genética , Muda/genética , Ninfa/genética , Filogenia , Interferencia de ARN , Alas de Animales/crecimiento & desarrollo
16.
Nano Lett ; 20(5): 3160-3168, 2020 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-32207627

RESUMEN

How an interfacial superconductivity emerges during the nucleation and epitaxy is of great importance not only for unveiling the physical insights but also for finding a feasible way to tune the superconductivity via interfacial engineering. In this work, we report the nanoscale creation of a robust and relatively homogeneous interfacial superconductivity (TC ≈ 13 K) on the epitaxial FeTe surface, by van der Waals epitaxy of single-quintuple-layer topological insulator Bi2Te3. Our study suggests that the superconductivity in the Bi2Te3/FeTe heterostructure is generated at the interface and that the superconductivity at the interface does not enhance or weaken with the increase of the Bi2Te3 thickness beyond 1 quintuple layer (QL). The observation of the topological surface states crossing Fermi energy in the Bi2Te3/FeTe heterostructure with the average Bi2Te3 thickness of about 20 QL provides further evidence that this heterostructure may potentially host Majorana zero modes.

17.
Small ; 16(35): e2002432, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32700457

RESUMEN

Reported herein is comprehensive study of a highly active and stable cobalt catalyst for overall water splitting. This composite SFCNF/Co1- x S@CoN, consisting of S-doped flexible carbon nanofiber (SFCNF) matrix, Co1- x S nanoparticles, and CoN coatings, is prepared by integration of electrospinning and atomic layer deposition (ALD) technique. Representative results include the following: 1) ultrathin CoN layer is deposited by ALD on the surface of flexible substrate without any sacrifice of SFCNF and Co1- x S; 2) the composite exhibits strong electrocatalytic activity in both acidic and basic solutions. The overpotentials of hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are 20 and 180 mV, respectively, at a current density of 10 mA cm-2 in basic medium. A small Tafel slope of 54.4 mV dec-1 is observed in 0.5 m H2 SO4 electrolyte; 3) tested as overall water splitting electrode, the composite records a current density of 10 mA cm-2 at a relative low cell voltage of 1.58 V and long-term stability for 20 h at a current density of up to 50 mA cm-2 . The superior performance for overall water splitting is probably attributed to the synergistic effect of Co1- x S and ALD CoN. Specifically, implementation of ALD can be extended to innovate nanostructured materials for overall water splitting and even other renewable energy aspects.

18.
Glob Chang Biol ; 26(6): 3356-3367, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32281177

RESUMEN

Plastic pollution is a global concern given its prevalence in aquatic and terrestrial ecosystems. Studies have been conducted on the distribution and impact of plastic pollution in marine ecosystems, but little is known on terrestrial ecosystems. Plastic mulch has been widely used to increase crop yields worldwide, yet the impact of plastic residues in cropland soils to soil health and crop production in the long term remained unclear. In this paper, using a global meta-analysis, we found that the use of plastic mulch can indeed increase crop yields on average by 25%-42% in the immediate season due to the increase of soil temperature (+8%) and moisture (+17%). However, the unabated accumulation of film residues in the field negatively impacts its physicochemical properties linked to healthy soil and threatens food production in the long term. It has multiple negative impacts on plant growth including crop yield (at the mean rate of -3% for every additional 100 kg/ha of film residue), plant height (-2%) and root weight (-5%), and soil properties including soil water evaporation capacity (-2%), soil water infiltration rate (-8%), soil organic matter (-0.8%) and soil available phosphorus (-5%) based on meta-regression. Using a nationwide field survey of China, the largest user of plastic mulch worldwide, we found that plastic residue accumulation in cropland soils has reached 550,800 tonnes, with an estimated 6%-10% reduction in cotton yield in some polluted sites based on current level of plastic residue content. Immediate actions should be taken to ensure the recovery of plastic film mulch and limit further increase in film residue loading to maintain the sustainability of these croplands.


Asunto(s)
Agricultura , Plásticos , China , Productos Agrícolas , Ecosistema , Abastecimiento de Alimentos , Suelo
19.
Clin Lab ; 66(10)2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-33073965

RESUMEN

BACKGROUND: CC chemokine ligand-18 (CCL-18) and CX3 chemokine ligand 1 (CX3CL1) are key factors of vascular and tissue injury in chronic respiratory diseases. Here, we investigated the value of CCL-18 and CX3CL1 in diagnosis and prognosis of patients with chronic obstructive pulmonary disease and chronic cor pulmonale (COPD&CCP). METHODS: First, we investigated the expression profile of CCL-18 and CX3CL1 in serum of COPD&CCP patients. Then the relationship of the level of CCL-18 and CX3CL1 with clinicopathological characteristics was analyzed. Subsequently, we evaluated the diagnostic accuracy of CCL-18 and CX3CL1 to discriminate COPD&CCP. The prognostic value and therapy outcome were also evaluated. RESULTS: Compared to healthy subjects, the level of CCL-18 (8.01 ± 2.01 ng/mL) and CX3CL1 (2,096.11 ± 306.09 ng/mL) was significantly increased in COPD&CCP patients (p < 0.05). The upregulation of CCL-18 and CX3CL1 was significantly correlated with clinicopathological characteristics including CRP, IL-6, FIB, NT-proBNP, FEV1, FEV1/FVC, PASP, LVEF, and T wave anomaly. The combination of CCL-18 and CX3CL1 showed high precision for discriminating COPD&CCP with high AUC values (0.828), sensitivity (66.1%), and specificity (92.5%). Furthermore, CCL-18 and CX3CL1 acted as independent factors which lead to poor clinical benefits and indicated poor prognosis of COPD&CCP patients. CONCLUSIONS: Taken together, our results indicated that CCL-18 and CX3CL1 could act as suitable biomarkers in prognosis and prognostic evaluation of COPD&CCP.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Enfermedad Cardiopulmonar , Quimiocina CX3CL1 , Quimiocinas CC , Humanos , Proyectos Piloto , Pronóstico , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico
20.
Int J Neurosci ; 130(11): 1156-1160, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31944864

RESUMEN

Purpose: Sjögren-Larsson syndrome is a rare, autosomal, recessive neurocutaneous disorder caused by mutations in the ALDH3A2 gene, which encodes the fatty aldehyde dehydrogenase enzyme. Deficiency in fatty aldehyde dehydrogenase results in an abnormal accumulation of toxic fatty aldehydes in the brain and skin, which cause spasticity, intellectual disability, ichthyosis, and other clinical manifestations. We present the clinical features and mutation analyses of a case of SLS.Materials and Methods: The family history and clinical data of the patient were collected. Genomic DNA was extracted from peripheral blood samples of the patient and her parents, and next-generation sequencing was performed. The candidate mutation sites that required further validation were then sequenced by Sanger sequencing. Bioinformatics software PSIPRED and RaptorX were used to predict the secondary and tertiary structures of proteins.Results: The patient, a five-year-old girl with complaints of cough for three days and intermittent convulsions for seven hours, was admitted to the hospital. Other clinical manifestations included spastic paraplegia, mental retardation, tooth defects, and ichthyosis. Brain magnetic resonance imaging showed periventricular leukomalacia. Genetic screening revealed compound heterozygous mutations in the ALDH3A2 gene: a frameshift mutation c.779delA (p.K260Rfs*6) and a missense mutation c.1157A > G (p.N386S). Neither of the ALDH3A2 alleles in the compound heterozygote patient were able to generate normal fatty aldehyde dehydrogenase, which were likely responsible for her phenotype of Sjögren-Larsson syndrome.Conclusion: The compound heterozygous mutations found in the ALDH3A2 gene support the diagnosis of Sjögren-Larsson syndrome in the patient and expand the genotype spectrum of the gene.


Asunto(s)
Aldehído Oxidorreductasas/genética , Síndrome de Sjögren-Larsson/diagnóstico , Síndrome de Sjögren-Larsson/genética , Preescolar , Femenino , Mutación del Sistema de Lectura , Humanos , Mutación Missense , Linaje , Síndrome de Sjögren-Larsson/fisiopatología
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