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1.
Pest Manag Sci ; 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38629775

RESUMEN

BACKGROUND: Saliva has a crucial role in determining the compatibility between piercing-sucking insects and their hosts. The brown planthopper (BPH) Nilaparvata lugens, a notorious pest of rice in East and Southeast Asia, secretes gelling and watery saliva when feeding on rice sap. Nlsalivap-5 (NlSP5) and Nlsalivap-7 (NlSP7) were identified as potential planthopper-specific gelling saliva components, but their biological functions remain unknown. RESULTS: Here, we showed by transcriptomic analyses that NlSP5 and NlSP7 were biasedly expressed in the salivary glands of BPHs. Using the clustered regularly interspaced short palindromic repeats (CRISPR)/Cas9-mediated genome-editing system, we constructed NlSP5 and NlSP7 homozygous mutants (NlSP5-/- and NlSP7-/-). Electrical penetration graph assay showed that NlSP5-/- and NlSP7-/- mutants exhibited abnormal probing and feeding behaviors. Bioassays revealed that the loss-of-function of NlSP5 and NlSP7 significantly reduced the fitness of BPHs, with extended developmental duration, shortened lifespan, reduced weight, and impaired fecundity and hatching rates. CONCLUSION: These findings deepen our understanding of the BPH-host interaction and may provide potential targets for the management of rice planthoppers. © 2024 Society of Chemical Industry.

3.
J Opt Soc Am A Opt Image Sci Vis ; 41(2): 241-251, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38437336

RESUMEN

A recently proposed method is upgraded to convert two amplitude phase modulation systems (APMSs) to pure phase elements (PPEs), for generating the stable propagation Bessel beam and the axial multifoci beam, respectively. Phase functions of the PPEs are presented analytically. Numerical simulations by the complete Rayleigh-Sommerfeld method demonstrate that the converted PPE has implemented the same optical functionalities as the corresponding APMS, in either the longitudinal or the transverse direction. Compared with the traditional APMS, the converted PPE possesses many advantages such as fabrication process simplification, system complexity reduction, production cost conservation, alignment error avoidance, and experimental precision enhancement. These inherent advantages position the PPE as an ideal choice and driving force behind further advancements in optical system technology.

4.
Biochem Biophys Rep ; 36: 101566, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37965067

RESUMEN

Cancer stem cells (CSCs) are crucial in the pathogenesis of human cancers. Existing studies reported that microRNA (miRNA) modulates the stemness of CSCs. We discovered that renal cell CSCs have suppressed miR-381. Suppression of miR-381 promotes renal cell tumorigenesis and CSC-like properties. Furthermore, the forced expression of miR-381 prevents the renal cell tumorigenesis and CSC-like properties. Mechanistically, renal cell CSCs have been found to interact with SOX4 through miR-381 directly. miR-381 inhibits renal cell CSC-like properties and tumorigenesis via downregulating SOX4. Examination of the patient-derived xenografts (PDX) and patient cohorts reveals that miR-381 may be able to forecast the advantages of Sunitinib in RCC patients. Moreover, the introduction of SOX4 could reverse the sensitivity of miR-381 overexpression RCC cells to Sunitinib-induced cell apoptosis. These results indicated that miR-381 is critical in renal cell CSC-like properties and tumorigenesis, making it the ideal therapeutic target for RCC.

5.
J Control Release ; 364: 718-733, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37944669

RESUMEN

Adipose-derived mesenchymal stem cell-derived small extracellular vesicles (Ad-MSC-sEVs/AMEs) combined with scaffold materials are used in tissue-engineered bladders; however, the lack of retention leads to limited distribution of AMEs in the scaffold areas and low bioavailability of AMEs after bladder reconstruction. To improve retention of AMEs, we developed a novel strategy that modifies the surface charge of the bladder acellular matrix (BAM) via oxidative self-polymerization of dopamine-reducing graphene oxide (GO) and AMEs using ε-polylysine-polyethylene-distearyl phosphatidylethanolamine (PPD). We evaluated two BAM surface modification methods and evaluated the biocompatibility of materials and PPD and electrostatic adherence effects between PPD-modified AMEs and rGO-PDA/BAM in vivo and in vitro. Surface modification increased retention of AMEs, enhanced regeneration of bladder structures, and increased electrical conductivity of rGO-PDA/BAM, thereby improving bladder function recovery. RNA-sequencing revealed 543 miRNAs in human AMEs and 514 miRNAs in rat AMEs. A Venn diagram was used to show target genes of miRNA with the highest proportion predicted by the four databases; related biological processes and pathways were predicted by KEGG and GO analyses. We report a strategy for improving bioavailability of AMEs for bladder reconstruction and reveal that enriched miR-21-5p targets PIK3R1 and activates the PI3K/Akt pathway to promote cell proliferation and migration.


Asunto(s)
Vesículas Extracelulares , Células Madre Mesenquimatosas , MicroARNs , Ratas , Humanos , Animales , Ingeniería de Tejidos/métodos , Vejiga Urinaria/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Matriz Extracelular/metabolismo , MicroARNs/metabolismo
6.
Opt Lett ; 48(20): 5419-5422, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37831882

RESUMEN

We propose what we believe to be a new kind of diffractive phase element, i.e., vortex phase plate (VPP) with phase singularities along the azimuth direction. Phase function of the proposed VPP is given analytically. Axial intensity oscillations of propagating Bessel beams are ideally suppressed by using the proposed VPP. Compared with the traditional amplitude mask, the proposed VPP takes such advantages as a simpler fabrication procedure and a lower cost.

7.
J Opt Soc Am A Opt Image Sci Vis ; 40(7): 1425-1433, 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37706744

RESUMEN

The binary amplitude filter (BAF) is employed to generate stable propagation Bessel beams and axial multifoci beams, rather than the traditional continuous amplitude filter (CAF). We introduce a parameter along the azimuth direction, i.e., angular order of the BAF, to weaken transverse intensity asymmetry. Numerical simulations reveal that the BAF implements the same optical functionalities as the CAF. The BAF holds advantages over the traditional CAF: a simpler fabrication process, a lower cost, and a higher experimental accuracy. It is believed that the BAF should have many practical applications in future optical systems.

8.
iScience ; 26(9): 107495, 2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37636036

RESUMEN

Timely diagnosis of Schistosoma infection, particularly in the early stage is crucial for identifying infected hosts and then taking effective control strategies. Here, metagenomic next-generation sequencing was used to identify pathogen-specific circulating DNAs (cDNAs) in the sera/plasma of New Zealand rabbits infected with S. japonicum, and the identified cDNAs were validated by PCR and qPCR. Loop-mediated isothermal amplification (LAMP)-based CRISPR-Cas12a and recombinase polymerase amplification-based lateral flow strip (RPA-LF) methods combined with the newly identified cDNA were developed to evaluate the potentials for diagnosing murine and human schistosomiasis. The results indicated that twenty-two cDNAs were identified. The developed LAMP-based CRISPR/Cas12a and RPA-LF methods showed a good potential for diagnosing murine or human schistosomiasis as early as 5 days of post-infection with 5 cercariae infection. In a word, S. japonicum specific cDNAs in circulation of infected hosts could be effective biomarkers for detecting Schistosoma infection particularly for early stages.

9.
Polymers (Basel) ; 15(14)2023 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-37514523

RESUMEN

Ethylene-vinyl acetate copolymer (EVA) was added at different contents to the thermoplastic polyurethane (TPU) matrix to form a non-compatible blending system, and foaming materials with high pore density were prepared using the supercritical carbon dioxide extrusion method. The influence of the phase morphology and crystal morphology of the TPU/EVA blend on its foaming behavior was studied. The results show that EVA changed the phase morphology and crystal morphology of the blends, leading to the improved melt viscosity and crystallinity of the blend system. At the same time, interfacial nucleation increases the density of cells and decreases the cell thickness and size, which is beneficial for improving the foaming properties of the blends. For the EVA content of 10% (mass fraction), the cell size is small (105.29 µm) and the cell density is the highest (3.74 × 106 cells/cm3). Based on the TPU/EVA phase morphology and crystal morphology, it is found that the sea-island structure of the blend has better foaming properties than the bicontinuous structure.

10.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 31(3): 850-854, 2023 Jun.
Artículo en Chino | MEDLINE | ID: mdl-37356950

RESUMEN

OBJECTIVE: To investigate the causes of ineffectiveness of platelet transfusion with monoclonal antibody solid phase platelet antibody test (MASPAT) matching in patients with allogeneic hematopoietic stem cell transplantation and explore the strategies of platelet transfusion. METHODS: A case of donor-specific HLA antibodies (DSA) induced by transfusion which ultimately resulted in transplantation failure and ineffective platelet transfusion with MASPAT matching was selected, and the causes of ineffective platelet transfusion and platelet transfusion strategy were retrospectively analyzed. RESULTS: The 32-year-old female patient was diagnosed as acute myeloid leukemia (high risk) in another hospital with the main symptoms of fever and leukopenia, who should be admitted for hematopoietic stem cell transplantation after remission by chemotherapy. In the course of chemotherapy, DSA was generated due to platelet transfusion, and had HLA gene loci incompatible with the donor of the first transplant, leading to the failure of the first transplant. The patient received platelet transfusion for several times before and after transplantation, and the results showed that the effective rate of MASPAT matched platelet transfusion was only 35.3%. Further analysis showed that the reason for the ineffective platelet transfusion was due to the missed detection of antibodies by MASPAT method. During the second hematopoietic stem cell transplantation, the DSA-negative donor was selected, and the matching platelets but ineffective transfusion during the primary transplantation were avoided. Finally, the patient was successfully transplanted and discharged from hospital. CONCLUSIONS: DSA can cause graft failure or render the graft ineffective. For the platelet transfusion of patients with DSA, the platelet transfusion strategy with matching type only using MASPAT method will miss the detection of antibodies, resulting in invalid platelet transfusion.


Asunto(s)
Trasplante de Células Madre Hematopoyéticas , Transfusión de Plaquetas , Femenino , Humanos , Adulto , Anticuerpos Monoclonales , Estudios Retrospectivos , Antígenos HLA
11.
Sci Rep ; 13(1): 8510, 2023 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-37231062

RESUMEN

Manganese dioxide nanoparticles (MnO2-NPs) have a wide range of applications in biomedicine. Given this widespread usage, it is worth noting that MnO2-NPs are definitely toxic, especially to the brain. However, the damage caused by MnO2-NPs to the choroid plexus (CP) and to the brain after crossing CP epithelial cells has not been elucidated. Therefore, this study aims to investigate these effects and elucidate potential underlying mechanisms through transcriptomics analysis. To achieve this objective, eighteen SD rats were randomly divided into three groups: the control group (control), low-dose exposure group (low-dose) and high-dose exposure group (high-dose). Animals in the two treated groups were administered with two concentrations of MnO2-NPs (200 mg kg-1 BW and 400 mg kg-1 BW) using a noninvasive intratracheal injection method once a week for three months. Finally, the neural behavior of all the animals was tested using a hot plate tester, open-field test and Y-type electric maze. The morphological characteristics of the CP and hippocampus were observed by H&E stain, and the transcriptome of CP tissues was analysed by transcriptome sequencing. The representative differentially expressed genes were quantified by qRT-PCR. We found that treatment with MnO2-NPs could induce learning capacity and memory faculty decline and destroy the structure of hippocampal and CP cells in rats. High doses of MnO2-NPs had a more obvious destructive capacity. For transcriptomic analysis, we found that there were significant differences in the numbers and types of differential genes in CP between the low- and high-dose groups compared to the control. Through GO terms and KEGG analysis, high-dose MnO2-NPs significantly affected the expression of transporters, ion channel proteins, and ribosomal proteins. There were 17 common differentially expressed genes. Most of them were transporter and binding genes on the cell membrane, and some of them had kinase activity. Three genes, Brinp, Synpr and Crmp1, were selected for qRT-PCR to confirm their expression differences among the three groups. In conclusion, high-dose MnO2-NPs exposure induced abnormal neurobehaviour, impaired memory function, destroyed the structure of the CP and changed its transcriptome in rats. The most significant DEGs in the CP were within the transport system.


Asunto(s)
Nanopartículas , Óxidos , Ratas , Animales , Óxidos/toxicidad , Óxidos/química , Compuestos de Manganeso/química , Plexo Coroideo , Transcriptoma , Ratas Sprague-Dawley , Nanopartículas/toxicidad
12.
Artículo en Inglés | MEDLINE | ID: mdl-37165492

RESUMEN

PURPOSE: Homocysteine (Hcy)-induced endothelial cell injury is a key event in atherosclerosis pathogenesis. In this study, we aimed to explore the mechanisms underlying Hcy-induced endothelial injury by assessing the effects of Hcy on endothelial cell proliferation and the microRNA (miR)-129-5p/fibroblast growth factor 2 (FGF2) axis. METHODS: Human umbilical vein endothelial cells (HUVECs) were treated with Hcy to construct an endothelial cell injury model. Expression levels of FGF2 in Hcy-induced HUVECs were determined using quantitative real-time polymerase chain reaction and western blotting. An FGF2 overexpression lentiviral vector was constructed to upregulate FGF2 expression in HUVECs via lentivirus transduction. A cell counting kit-8 assay was used to explore the effects of FGF2 overexpression on HUVEC proliferation. An upstream regulatory miRNA was predicted, and its target-binding relationship with FGF2 was evaluated using a dual-luciferase reporter assay. RESULTS: We found that FGF2 expression in HUVECs was inhibited by Hcy treatment. Lentivirus transduction led to the overexpression of FGF2 in HUVECs, which significantly reversed the effect of Hcy on endothelial cell proliferation. miR-129-5p was experimentally validated as an upstream regulator of FGF2, and its decreased levels in HUVECs led to increased FGF2 expression. In addition, HUVEC proliferation was enhanced by the knockdown of miR-129-5p, and this effect was reversed by Hcy treatment. CONCLUSION: Taken together, the results of this study revealed that Hcy inhibits FGF2 expression in HUVECs, and FGF2 is regulated by upstream miR-129-5p to improve the effect of Hcy on endothelial cell proliferation.

13.
J Chem Phys ; 158(17)2023 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-37129304

RESUMEN

We outline techniques for the control and measurement of the nucleation of crystalline materials. Small angle x-ray scattering/wide angle x-ray scattering x-ray diffraction measurements are presented that demonstrate the impact of low power, continuous, non-cavitational ultrasound on the nucleation and crystallization of a wax-n-eicosane dissolved in a heptane/toluene solvent. A mathematical-physical approach based on the rectification of heat and mass transport by such a low power oscillating pressure field is outlined, and it is suggested that this approach be combined with dissipative particle dynamics computational modeling to develop a predictive method capable of modeling the impact of low power oscillating pressure fields (acoustics and ultrasonics) on a wide range of nucleating systems. Combining the ultrasound pitch and catch speed of sound measurements with low power harmonically oscillating pressure fields to monitor and control nucleation presents the prospect of entirely new industrially significant methods of process control in crystallization. It also offers new insights into nucleation processes in general. However, for the acoustic control technique to be widely applied , further theoretical and modeling work will be necessary since, at present, we are unable to predict the precise effect of low power ultrasound in any given situation.

14.
Microvasc Res ; 148: 104541, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37116781

RESUMEN

OBJECTIVE: To investigate the feasibility of laser speckle contrast imaging (LSCI) for monitoring urethral blood flow (UBF). MATERIALS AND METHODS: In this study, 18 healthy, virgin female Sprague-Dawley rats aged 8-week-old were used. The animals were divided into the sham group (n = 9) and the vaginal distension (VD) group (n = 9). The sham group underwent one catheterization of the vagina without distension and the VD group underwent one VD. Following the VD or sham treatment for one week, LSCI assessment of urethral blood flow was performed during bladder filling and leak point pressure (LPP) process. RESULTS: During the LPP process, in the VD group, the mean LPP was significantly lower than in the sham group (p < 0.05) and the mean UBF level was also significantly lower than in the sham group (p < 0.05) in the LPP condition. The mean relative change of UBF (Δ Flow) was significantly different between the sham group and VD group. The value was 0.646 ± 0.229 and 0.295 ± 0.19, respectively (p < 0.05). During the bladder filling process, the VD group had a significant lower mean UBF level than the sham group under full bladder conditions (p = 0.008). The mean ΔFlow was also significantly lower than in the sham group. The value was 0.115 ± 0.121 and 0.375 ± 0.127, respectively (p = 0.016). CONCLUSIONS: The results confirmed that LSCI was able to determine UBF in female rats. The VD group had lower baseline UBF and lower increases in UBF during bladder filling and LPP process compared with the sham group.


Asunto(s)
Imágenes de Contraste de Punto Láser , Incontinencia Urinaria de Esfuerzo , Ratas , Femenino , Animales , Ratas Sprague-Dawley , Incontinencia Urinaria de Esfuerzo/terapia , Vagina/fisiología , Uretra/fisiología , Modelos Animales de Enfermedad
15.
ACS Appl Mater Interfaces ; 15(10): 13086-13096, 2023 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-36853078

RESUMEN

The agglomeration of graphene sheets and undesired pore size distribution usually lead to unsatisfactory electrochemical properties of reduced graphene oxide (RGO) film electrodes. Herein, crumpled exfoliated graphene (EG) sheets are adopted as the microstructure-regulating agent to tune the morphology and micro-/mesopore amounts with the aim of increasing active surface sites and ion transportation paths in electrodes. With the optimum ratio between EG and GO, the resulting 75%-EG/RGO shows significantly improved specific gravimetric capacitance (Cs) and rate capability when compared with pure RGO electrodes in a symmetrical supercapacitor system. Moreover, when coupling the 75%-EG/RGO cathode with a Zn anode to form a Zn ion hybrid supercapacitor (ZHS), the 75%-EG/RGO exhibits a much higher Cs of 327.39 F g-1 at 0.1 A g-1 and can maintain 91.7% capacitance after 8000 cycles. Systematic ex situ X-ray diffraction (XRD) and X-ray photoelectron spectra (XPS) measurements reveal that the charge storage mechanism is based on both reversible physical adsorption and dual ion uptake. Furthermore, the quasi-solid-state flexible ZHS also presents high capacitive performance and can maintain ∼100% capacitance under various bending states, demonstrating potential application in wearable electronics. This strategy opens up a new path for constructing high-performance graphene film electrodes.

16.
Ying Yong Sheng Tai Xue Bao ; 34(1): 196-202, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36799394

RESUMEN

Precipitation and landscape pattern are two main factors affecting runoff process of the watershed. Understanding their runoff effect is of great significance to water resources management and ecological construction of watershed. Based on the data of precipitation, runoff, and land use from 1958 to 2020, we analyzed the characteristics of precipitation, landscape pattern and runoff in Lianshui watershed in red soil hilly area of southern Jiangxi Pro-vince, established the relationship between precipitation, landscape pattern and annual runoff, flood runoff, low runoff, respectively. The results showed that the annual precipitation, runoff and annual maximum one-day runoff in the watershed showed a non-significant downward trend during the study period, while the annual minimum one-day runoff showed a non-significant upward trend but with the largest inter-annual variation range. Forested land was the landscape type with the highest proportion in watershed, and other woodland had the most dramatic variation. At the landscape level, Shannon diversity index, Shannon evenness index, patch density and landscape shape index increased from 1.125, 0.541, 0.667 and 16.925 in 1980 to 1.348, 0.614, 0.731 and 18.172 in 2020, respectively, while the landscape contagion index decreased from 68.237 in 1980 to 64.293 in 2020. The overall landscape diversity, fragmentation degree and shape complexity of the watershed increased, the spatial distribution tended to be uniform, and the connectivity decreased. The correlation coefficients between precipitation and annual runoff, flood runoff, low runoff were 0.907, 0.594 and 0.558, respectively. At the class level, the reduction of cultivated land had a greater impact on annual runoff, flood runoff, and low runoff, while the overall change at the landscape level promoted a decrease in annual runoff and flood runoff and an increase in low runoff. The contribution rate of precipitation variation and landscape pattern evolution to the change of annual runoff, flood runoff ,and low runoff were 17.8%, 82.2% and 1.5%, 98.5% and -8.8%, 108.8%, respectively. Our results could provide theoretical refe-rence for landscape pattern allocation and comprehensive management of soil and water loss.


Asunto(s)
Bosques , Suelo , Recursos Hídricos , Agua/análisis , China , Monitoreo del Ambiente
17.
Artículo en Chino | WPRIM (Pacífico Occidental) | ID: wpr-982140

RESUMEN

OBJECTIVE@#To investigate the causes of ineffectiveness of platelet transfusion with monoclonal antibody solid phase platelet antibody test (MASPAT) matching in patients with allogeneic hematopoietic stem cell transplantation and explore the strategies of platelet transfusion.@*METHODS@#A case of donor-specific HLA antibodies (DSA) induced by transfusion which ultimately resulted in transplantation failure and ineffective platelet transfusion with MASPAT matching was selected, and the causes of ineffective platelet transfusion and platelet transfusion strategy were retrospectively analyzed.@*RESULTS@#The 32-year-old female patient was diagnosed as acute myeloid leukemia (high risk) in another hospital with the main symptoms of fever and leukopenia, who should be admitted for hematopoietic stem cell transplantation after remission by chemotherapy. In the course of chemotherapy, DSA was generated due to platelet transfusion, and had HLA gene loci incompatible with the donor of the first transplant, leading to the failure of the first transplant. The patient received platelet transfusion for several times before and after transplantation, and the results showed that the effective rate of MASPAT matched platelet transfusion was only 35.3%. Further analysis showed that the reason for the ineffective platelet transfusion was due to the missed detection of antibodies by MASPAT method. During the second hematopoietic stem cell transplantation, the DSA-negative donor was selected, and the matching platelets but ineffective transfusion during the primary transplantation were avoided. Finally, the patient was successfully transplanted and discharged from hospital.@*CONCLUSIONS@#DSA can cause graft failure or render the graft ineffective. For the platelet transfusion of patients with DSA, the platelet transfusion strategy with matching type only using MASPAT method will miss the detection of antibodies, resulting in invalid platelet transfusion.


Asunto(s)
Femenino , Humanos , Adulto , Transfusión de Plaquetas , Anticuerpos Monoclonales , Estudios Retrospectivos , Antígenos HLA , Trasplante de Células Madre Hematopoyéticas
18.
J Org Chem ; 87(23): 16084-16089, 2022 12 02.
Artículo en Inglés | MEDLINE | ID: mdl-36395460

RESUMEN

Despite several synthetic approaches that have been developed for α-deuterated amino acids, the synthesis of ß-deuterated amino acids has remained a challenge. Herein, we disclose a palladium catalyzed H/D exchange protocol for a ß-deuterated N-protected amino amide, which can be converted to a ß-deuterated amino acid simply by removal of protecting groups. This protocol is highly efficient, simply manipulated, and appliable for deuterium-labeling of many amino amides. In addition, deuterium labeling of phenylalanine derivatives was also successful when pivalic acid served as an additive to promote the H/D exchange process.


Asunto(s)
Aminoácidos , Paladio , Deuterio , Amidas , Catálisis
19.
Ying Yong Sheng Tai Xue Bao ; 33(8): 2251-2259, 2022 Aug.
Artículo en Chino | MEDLINE | ID: mdl-36043834

RESUMEN

Baseflow is an important part of water resources. Exploring the characteristics of baseflow and its response to precipitation is of great significance to optimize the partition of water resources. Based on the data of daily precipitation and runoff from 1982 to 2019 in Jiuqushui watershed, we analyzed the characteristics of baseflow change, investigated the time lag effect of baseflow on precipitation, and calculated the contribution rate of precipitation to baseflow change by using digital filtering method, cross wavelet transform method, and slope change ratio of accumulative quantity method. The results showed that during the study period, the variation trend of annual baseflow depth and annual baseflow index was not significant, with annual average values of 384.21 mm and 0.44, respectively. The depth of baseflow in spring and summer was greater than that in autumn and winter, while the baseflow index showed an opposite pattern. Annual precipitation affected the dynamic change of annual baseflow depth, with the effects in spring and summer being stronger than that in autumn and winter. The lag time of baseflow in spring, summer, autumn and winter were 3.5-10.3, 1.5-8.5, 2-10, 2-13 and 5-20.5 days, while the average annual lag time was 6.4, 4.9, 5.3, 6.8 and 10.8 days, respectively. The annual baseflow depth changed abruptly in 1992. The contribution rate of precipitation to baseflow change was 68.2%, and that of other factors was 31.8%. The results could provide scientific basis for evaluating the hydrological effects of forests and ensuring water ecological security of rivers in the red soil region of southern China.


Asunto(s)
Hidrología , Ríos , China , Bosques , Suelo
20.
Front Bioeng Biotechnol ; 10: 927036, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782501

RESUMEN

With the rapid development of nanotechnology and nanoscience, nanosafety assessment has raised public concern. Although many studies have illustrated that nanomaterials could lead to genotoxicity, the early alterations of DNA methylation with nanomaterials under low-dose exposure have not been completely clear. In this study, we investigated the potential effect and molecular mechanism of AgNPs on the alternation of DNA methylation fingerprints in HEK293T cells under sublethal exposure. Intriguingly, silver nanoparticle treatment increased 5-mC level and changed methylation-related enzyme contents. Mechanistically, we scrutinized the changes in the molecular signaling and biological functions by means of MeDIP-Seq and RNA-seq. Our results revealed that AgNPs might undermine a number of vital regulatory networks including the metabolic processes, biological regulation and other cellular processes. More specifically at the DNA methylation fingerprints, there were 12 up-regulated and simultaneous hypomethylated genes, and 22 down-regulated and concomitant hypermethylated genes in HEK293T cells responding to AgNPs. Notably, these genes were primarily involved in lipid metabolism and ion metabolism. Together, these responsive genes might be used as early sensitive indicators for the variations of early epigenetic integrity through changing the DNA methylation fingerprints, as reflective of biological risk and toxicity of silver nanoparticles under realistic exposure scenarios.

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