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1.
J Am Chem Soc ; 146(6): 4178-4186, 2024 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-38301245

RESUMEN

DNA origami, comprising a long folded DNA scaffold and hundreds of linear DNA staple strands, has been developed to construct various sophisticated structures, smart devices, and drug delivery systems. However, the size and diversity of DNA origami are usually constrained by the length of DNA scaffolds themselves. Herein, we report a new paradigm of scaling up DNA origami assembly by introducing a novel branched staple concept. Owing to their covalent characteristics, the chemically conjugated branched DNA staples we describe here can be directly added to a typical DNA origami assembly system to obtain super-DNA origami with a predefined number of origami tiles in one pot. Compared with the traditional two-step coassembly system (yields <10%), a much greater yield (>80%) was achieved using this one-pot strategy. The diverse superhybrid DNA origami with the combination of different origami tiles can be also efficiently obtained by the hybrid branched staples. Furthermore, the branched staples can be successfully employed as the effective molecular glues to stabilize micrometer-scale, super-DNA origami arrays (e.g., 10 × 10 array of square origami) in high yields, paving the way to bridge the nanoscale precision of DNA origami with the micrometer-scale device engineering. This rationally developed assembly strategy for super-DNA origami based on chemically conjugated branched staples presents a new avenue for the development of multifunctional DNA origami-based materials.


Asunto(s)
Nanoestructuras , Nanoestructuras/química , Nanotecnología , ADN/química , Análisis de Secuencia por Matrices de Oligonucleótidos , Conformación de Ácido Nucleico
2.
J Am Chem Soc ; 145(16): 9343-9353, 2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37070733

RESUMEN

DNA origami has played an important role in various biomedical applications, including biosensing, bioimaging, and drug delivery. However, the function of the long DNA scaffold involved in DNA origami has yet to be fully exploited. Herein, we report a general strategy for the construction of a genetically encoded DNA origami by employing two complementary DNA strands of a functional gene as the DNA scaffold for gene therapy. In our design, the complementary sense and antisense strands can be directly folded into two DNA origami monomers by their corresponding staple strands. After hybridization, the assembled genetically encoded DNA origami with precisely organized lipids on the surface can function as the template for lipid growth. The lipid-coated and genetically encoded DNA origami can efficiently penetrate the cell membrane for successful gene expression. After decoration with the tumor-targeting group, the antitumor gene (p53) encoded DNA origami can elicit a pronounced upregulation of the p53 protein in tumor cells to achieve efficient tumor therapy. The targeting group-modified, lipid-coated, and genetically encoded DNA origami has mimicked the functions of cell surface ligands, cell membrane, and nucleus for communication, protection, and gene expression, respectively. This rationally developed combination of folding and coating strategies for genetically encoded DNA origami presents a new avenue for the development of gene therapy.


Asunto(s)
Nanoestructuras , Proteína p53 Supresora de Tumor , Proteína p53 Supresora de Tumor/genética , ADN/genética , Sistemas de Liberación de Medicamentos , ADN Complementario , Lípidos , Conformación de Ácido Nucleico , Nanotecnología/métodos
3.
Angew Chem Int Ed Engl ; 62(51): e202315093, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-37906116

RESUMEN

DNA nanostructures have played an important role in the development of novel drug delivery systems. Herein, we report a DNA origami-based CRISPR/Cas9 gene editing system for efficient gene therapy in vivo. In our design, a PAM-rich region precisely organized on the surface of DNA origami can easily recruit and load sgRNA/Cas9 complex by PAM-guided assembly and pre-designed DNA/RNA hybridization. After loading the sgRNA/Cas9 complex, the DNA origami can be further rolled up by the locking strands with a disulfide bond. With the incorporation of DNA aptamer and influenza hemagglutinin (HA) peptide, the cargo-loaded DNA origami can realize the targeted delivery and effective endosomal escape. After reduction by GSH, the opened DNA origami can release the sgRNA/Cas9 complex by RNase H cleavage to achieve a pronounced gene editing of a tumor-associated gene for gene therapy in vivo. This rationally developed DNA origami-based gene editing system presents a new avenue for the development of gene therapy.


Asunto(s)
Sistemas CRISPR-Cas , Edición Génica , Sistemas CRISPR-Cas/genética , ARN Guía de Sistemas CRISPR-Cas , Terapia Genética , ADN/genética
4.
Anal Chem ; 94(2): 1178-1186, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-34985881

RESUMEN

As a class of electrochemiluminescence (ECL) enhancers, silver-based materials have broad application prospects. In this work, a novel silver metal-organic framework (AgMOF) was developed as a self-enhanced ECL emitter by one-step mixing and standing at room temperature. The AgMOF could produce strong and stable ECL emissions based on a double-amplification method, which originated from the aggregation-induced ECL emission of ligands and catalyzing S2O82- to produce more SO4•- by silver. Moreover, an ECL resonance energy transfer (ECL-RET) biosensor with AgMOF as a donor and BHQ2 as an acceptor was fabricated by duplex-specific nuclease (DSN)-assisted target recycling amplification to detect miRNA-107. The biosensor exhibited a strong ECL-RET effect due to the higher ECL emission of the AgMOF and perfect match of spectra between the AgMOF and BHQ2. Upon the introduction of DSN and target miRNAs, the specific DNA-RNA binding and nuclease cleaving could trigger the detachment of BHQ2, resulting in an increased ECL signal of AgMOF. Benefiting from the ECL-RET and DSN-assisted target recycling amplification methods, this biosensor achieved a wide linear relationship range from 20 to 120 fM with a low limit of detection (4.33 fM). This research presents an effective emitter for self-enhanced ECL systems, which broadens the potential ECL applications of silver-based nanomaterials.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , MicroARNs , Técnicas Biosensibles/métodos , Técnicas Electroquímicas/métodos , Transferencia de Energía , Límite de Detección , Mediciones Luminiscentes/métodos , Plata
5.
Chemistry ; 28(54): e202201437, 2022 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-35735906

RESUMEN

Metal-organic frameworks (MOFs) with abundant active sites, a class of materials composed of metal nodes and organic ligands, is widely used for photocatalytic degradation of pollutants. However, the rapid recombination of photoinduced carriers of MOFs limits its photocatalytic degradation performance. Herein, Ti3 C2 Tx nanosheets-based NH2 -MIL-101(Fe) hybrids with Schottky-heterojunctions were fabricated by in situ hydrothermal assembly for improved photocatalytic activity. The photodegradation efficiencies of the NH2 -MIL-101(Fe)/Ti3 C2 Tx (N-M/T) hybrids for phenol and chlorophenol were 96.36 % and 99.83 % within 60 minutes, respectively. The N-M/T Schottky-heterojunction duly transferred electrons to the Ti3 C2 Tx nanosheets surface via built-in electric fields, effectively suppressing the recombination of photogenerated carriers, thereby improving the photocatalytic performance of NH2 -MIL-101(Fe). Moreover, the Fe-mixed-valence in the N-M/T led to improvement in the efficiency of the in situ generated photo-Fenton reactions, further enhancing the photocatalytic activity with more generated reactive oxygen species (ROS). The study proposes a highly effective removal of phenolic pollutants in wastewater.


Asunto(s)
Clorofenoles , Contaminantes Ambientales , Estructuras Metalorgánicas , Ligandos , Estructuras Metalorgánicas/química , Fenoles , Especies Reactivas de Oxígeno , Titanio , Aguas Residuales
6.
Fish Shellfish Immunol ; 128: 260-268, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35934240

RESUMEN

Diplothylacus sinensis is reported as an intriguing parasitic barnacle that can negatively affect the growth, molting, reproduction in several commercially important portunid crabs. To better understand the molecular mechanisms of host-parasite interactions, we characterized the gene expression profiles from the healthy and D. sinensis infected Portunus sanguinolentus by high-through sequence method. Totally, the transcriptomic analysis generated 52, 266, 600 and 51, 629, 604 high quality reads from the infected and control groups, respectively. The clean reads were assembled to 90,740 and 69,314 unigenes, with the average length of 760 bp and 709 bp, respectively. The expression analysis showed that 18,959 genes were significantly changed by the parasitism of D. sinensis, including 4769 activated genes and 14,190 suppressed genes. The differentially expressed genes were categorized into 258 KEGG pathways and 647 GO terms. The GO analysis mapped 13 DEGs related to immune system process and 32 DEGs related to immune response, respectively, suggesting a potential alteration of transcriptional expression patterns in complement cascades of P. sanguinolentus. Additionally, 4 representative molting-related genes were down-regulated in parasitized group, indicating D. sinensis infection appeared to suppress the producing of ecdysteroid hormones. In conclusion, the present study improves our understanding on parasite-host interaction mechanisms, which focuses the function of Ecdysone receptor, Toll-like receptor and cytokine receptor of crustacean crabs infestation with rhizocephalan parasites.


Asunto(s)
Braquiuros , Parásitos , Thoracica , Animales , Braquiuros/genética , Ecdisona , Ecdisteroides , Perfilación de la Expresión Génica , Masculino , Receptores de Citocinas/genética , Natación , Thoracica/genética , Transcriptoma
7.
Anal Chem ; 93(42): 14178-14186, 2021 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-34637279

RESUMEN

Developing a coreactant-free ratiometric electrochemiluminescence (ECL) strategy based on a single luminophore to achieve more accurate and sensitive microRNA (miRNA) detection is highly desired. Herein, utilizing zinc-metal organic frameworks (Zn-MOFs) as the single luminophore, a novel dual-potential ratiometric ECL biosensor was constructed for ultrasensitive detection of miRNA-133a. The as-prepared Zn-MOFs exhibited simultaneous cathode and anode ECL emission. Furthermore, the Zn-MOFs were confirmed to be a multichannel ECL sensing platform with excellent annihilation and coreactant ECL emission. The corresponding ECL behaviors were investigated in detail. Benefiting from the hybridization chain reaction (HCR) amplification technology, N,N-diethylethylenediamine (DEAEA) was modified on hairpin DNA, and the gained products loaded with quantities of DEAEA enhanced the anodic ECL intensity of Zn-MOFs. In the presence of miRNA-133a, the ECL intensity ratio of anode to cathode (Ia/Ic) was significantly increased, which realized the ultrasensitive ratiometric detection of miRNA-133a. In addition, without an exogenous coreactant, the biosensor revealed superb accuracy and stability. Under optimal conditions, the detection linearity of miRNA-133a was from 50 aM to 50 fM with a low detection limit of 35.8 aM (S/N = 3). This is the first work to use Zn-MOFs as a single emitter for reliable ratiometric ECL bioanalysis, which provides a new perspective for fabricating a ratiometric ECL biosensor platform.


Asunto(s)
Técnicas Biosensibles , Estructuras Metalorgánicas , MicroARNs , Técnicas Electroquímicas , Límite de Detección , Mediciones Luminiscentes , Zinc
8.
Sensors (Basel) ; 22(1)2021 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-35009823

RESUMEN

The concentration of trace gases in the atmospheric environment is extremely low, but it has a great impact on the living environment of organisms. Photoacoustic spectroscopy has attracted extensive attention in the field of trace gas detection because of its high sensitivity, good selectivity, and fast response. As the core of a photoacoustic detection setup, the photoacoustic cell has a significant impact on detection performance. To improve detection sensitivity, a sphere-tube coupled photoacoustic cell (STPAC) was developed, which was mainly composed of a diffuse-reflective sphere and an acoustic resonance tube. Modulated light was reflected multiple times in the sphere to increase optical path, and photoacoustic (PA) signals were further amplified by the tube. Based on STPAC, a PA gas detection setup was built with a laser diode (LD) at 450 nm as the light source. The experimental results showed that the minimum detection limit (noise equivalent concentration, NEC) of NO2 was ~0.7 parts per billion (ppb). Compared with the T-type PA cell (TPAC) in which the modulated light passed through the sphere, the signal-to-noise ratio of STPAC was increased by an order of magnitude at the same concentration of the NO2 sample.


Asunto(s)
Gases , Dióxido de Nitrógeno , Acústica , Relación Señal-Ruido , Análisis Espectral
9.
Phys Chem Chem Phys ; 21(22): 11731-11739, 2019 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-31114818

RESUMEN

A novel family of two-dimensional (2D) crystalline metal superhalogens V3X8 (X = F, Cl, Br, I) with intrinsic magnetism was predicted using first-principles calculations in the framework of density functional theory (DFT). The calculation results show that the V3Cl8 monolayer is an intrinsic anti-ferromagnetic semiconductor (AFS) with an indirect bandgap of 0.086 eV at the PBE functional level, while the V3X8 (X = F, Br, I) monolayer exhibits a fascinating ferromagnetic half-metal (FH) property with 100% spin-polarization at the Fermi level. Such 2D materials possess robust dynamical stability as well as thermal stability at room temperature except for V3Br8. In addition, Monte Carlo simulations based on the Ising model with the classical Heisenberg model estimate a Curie temperature of approximately 77 K and 103 K for the V3F8 and V3I8 systems, respectively. Furthermore, we predict an extraordinary phenomenon induced by biaxial compressive strain from the ferromagnetic half-metal (FH) to the ferromagnetic semiconductor (FS) at 2% strain and then to the antiferromagnetic metal (AM) with the biaxial strain increasing up to about 6.3% in the 2D V3I8 monolayer. In the case of 2D V3F8, as the strain varies from -10% to 8%, a series of electronic and magnetic phase transitions of AFS-AM-FH-AFS will occur. These tunable magnetic and electronic properties of 2D halides originate from the competition between AFM direct nearest-neighbor d-d exchange and FM superexchange via halogen p states, which leads to a variety of magnetic states. The explored controllable magnetic properties, electronic properties and the high Curie temperature render the 2D V3I8 monolayer a promising candidate for applications in magnetic logic devices and strain sensor devices.

10.
PLoS One ; 19(5): e0299772, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38758836

RESUMEN

Tourism efficiency has become an important role in promoting tourism competitiveness and driving sustainable development. It is particularly important to identify and agnalyze the factors and mechanisms that affect efficiency. This paper firstly evaluates the tourism efficiency of 11 coastal provinces regions in China from 2010 to 2020 by using the DEA-BBC model that includes undesirable outputs. After that, it investigates the internal driving mechanism of the efficiency change through the Malmquist index and its decomposition. Finally, it analyzes the external influencing elements of tourist efficiency by the Tobit model. The results show that: (1) Although the average value of the tourism efficiency was changed from 0.727 to 0.707, it does not achieve the target. Its trend shows fluctuating from 2010-2020, which indicates that the tourism efficiency of most provincial regions is not optimal. The main factor that restricts tourism efficiency is scale efficiency. (2) By analyzing the dynamic trend, it is found that the average increase of technical efficiency is 14.0%, the average increase of technical change is 9.5%, and the average increase of MI index is 25.4%. It indicates that the overall tourism efficiency of 11 coastal provinces region in China is on the rise. (3) The spatial difference of tourism efficiency is significant, but there is no obvious spatial correlation. (4) The influencing factors of tourism efficiency are consumer demand, industrial structure, labor force and urbanization.


Asunto(s)
Turismo , China , Humanos , Desarrollo Sostenible/tendencias , Modelos Teóricos
11.
Photoacoustics ; 36: 100591, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38322617

RESUMEN

Atmospheric aerosols play a pivotal role in the earth-atmospheric system. Analyzing their optical properties, specifically absorption and scattering coefficients, is essential for comprehending the impact of aerosols on climate. When different optical properties of aerosols are individually measured using multiple devices, cumulative errors in the detection results inevitably occur. To address this challenge, based on photoacoustic spectroscopy (PAS) and integrating sphere (IS) scattering enhancement, a compact gas cell (PASIS-Cell) was developed. The PASIS-Cell comprises a dual-T-type photoacoustic cell (DTPAC) and an IS. IS is coupled with DTPAC through a transparent quartz tube, thereby enhancing the scattering signal without compromising the acoustic characteristics of DTPAC. Concurrently, DTPAC can realize high-performance photoacoustic detection of absorption signal. Experimental results demonstrate that PASIS-Cell can simultaneously invert atmospheric aerosol absorption and scattering coefficients, with a minimum detection limit of less than 1 Mm-1, showcasing its potential in the analysis of aerosol optical properties.

12.
Front Nutr ; 11: 1265878, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38439922

RESUMEN

Background: Lung cancer is the most common global cancer in terms of incidence and mortality. Its main driver is tobacco smoking. The identification of modifiable risk factors isa public health priority. Green tea consumption has been examined in epidemiological studies, with inconsistent findings. Thus, we aimed to apply Mendelian randomization to clarify any causal link between green tea consumption and the risk of lung cancer. Methods: We utilized a two-sample Mendelian randomization (MR) approach. Genetic variants served as instrumental variables. The goal was to explore a causal link between green tea consumption and different lung cancer types. Green tea consumption data was sourced from the UK Biobank dataset, and the genetic association data for various types of lung cancer were sourced from multiple databases. Our analysis included primary inverse-variance weighted (IVW) analyses and various sensitivity test. Results: No significant associations were found between green tea intake and any lung cancer subtypes, including non-small cell lung cancer (adenocarcinoma and squamous cell carcinoma) and small cell lung cancer. These findings were consistent when applying multiple Mendelian randomization methods. Conclusion: Green tea does not appear to offer protective benefits against lung cancer at a population level. However, lung cancer's complex etiology and green tea's potential health benefitssuggest more research is needed. Further studies should include diverse populations, improved exposure measurements and randomized controlled trials, are warranted.

13.
Biology (Basel) ; 12(1)2023 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-36671789

RESUMEN

Among the anthropogenic stresses that marine ecosystems face, biological invasions are one of the major threats. Recently, as a result of increasingly intense anthropogenic disturbance, numerous marine species have been introduced to their non-native ranges. However, many introduced species have uncertain original sources. This prevents the design and establishment of methods for controlling or preventing these introduced species. In the present study, genomic sequencing and population genetic analysis were performed to detect the geographic origin of the introduced Pinctada fucata population in the Mischief Reef of the South China Sea. The results of population genetic structure analysis showed a close relationship between the Mischief Reef introduced population and the Lingshui population, indicating that Lingshui may be the potential geographical origin. Furthermore, lower heterozygosity and nucleotide diversity were observed in the introduced population in Mischief Reef, indicating lower genetic diversity than in other native populations. We also identified some selected genomic regions and genes of the introduced population, including genes related to temperature and salinity tolerance. These genes may play important roles in the adaptation of the introduced population. Our study will improve our understanding of the invasion history of the P. fucata population. Furthermore, the results of the present study will also facilitate further control and prevention of invasion in Mischief Reef, South China Sea.

14.
Zhonghua Zhong Liu Za Zhi ; 34(1): 21-5, 2012 Jan.
Artículo en Zh | MEDLINE | ID: mdl-22490850

RESUMEN

OBJECTIVE: To investigate the relationship between p16 expression and cell proliferation and prognosis in gastric cancer patients. METHODS: Gastric cancer cell lines SGC-7901, MKN45, MKN28, human embryonic kidney cell line HEK293, human fibroblast cell line MRC-5, and surgical specimens of gastric carcinoma and adjacent normal gastric mucosa from 65 patients were included in this study. RT-PCR, MTT and FCM assays were used to detect p16 expression in gastric cancer cell lines and surgical specimens of gastric cancer. MTT assay was used to determine cancer cell viability and FCM to detect cell cycle. Kaplan-Meier survival curve and Log-Rank statistics were used to analyze the relationship between p16 expression and survival of petients with gastric cancer. RESULTS: Gastric cancer cell lines were mostly negative for p16 expression, and p16 was re-expressed after the cells transfected with p16 gene by adenovirus AdCMV-p16. p16 re-expression resulted in the decrease of cancer cell viability and cancer cell cycle arrest with increased G(1) phase and decreased S phase. p16 expression in cancer specimens was 32.3% (21/65), significantly lower than the 81.5% (53/65) in normal mucosa (χ(2) = 32.124, P < 0.001). The disease-free survival was significantly shorter in p16-negative patients than that in p16-positive patients (P < 0.01), but not the overall survival (P > 0.05). p16 expression was significantly correlated with differentiation and lymph node metastasis, but not significantly correlated with sex, age, tumor size or invasion depth of the gastric cancer. CONCLUSIONS: p16 gene is important for cancer cell proliferation. The inactivation gives cancer cells a high activity for proliferation and metastasis, and then influences the disease-free survival of gastric cancer patients.


Asunto(s)
Inhibidor p16 de la Quinasa Dependiente de Ciclina/metabolismo , Genes p16 , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Adenoviridae/genética , Adulto , Anciano , Puntos de Control del Ciclo Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Supervivencia sin Enfermedad , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Invasividad Neoplásica , ARN Mensajero/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Tasa de Supervivencia , Transfección
15.
Nanoscale ; 14(48): 17862-17870, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36458678

RESUMEN

Based on complementary base pairing, nucleic acid molecules have acted as engineerable building blocks to prepare versatile nanostructures with unique shapes and sizes. Benefiting from excellent programmability and biocompatibility, rationally designed nucleic acid nanostructures have been widely employed in biomedical applications. With the development of the chemical biology of nucleic acids, various stimuli-responsive nucleic acid nanostructures have been constructed by tailored chemical modification with multifunctional components. In this minireview, we summarize the representative and latest research about the employment of stimuli-responsive nucleic acid nanostructures for drug delivery in response to endogenous and exogenous stimuli (redox gradient, pH, nuclease, biomacromolecule, and light). We also discuss the broad prospects and remaining challenges of nucleic acid nanotechnology in biomedical applications.


Asunto(s)
Nanoestructuras , Ácidos Nucleicos , Ácidos Nucleicos/química , ADN/química , Nanoestructuras/química , Nanotecnología , Sistemas de Liberación de Medicamentos
16.
J Ophthalmol ; 2022: 6699596, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35223091

RESUMEN

AIM: To analyze the pooled incidence rate in repositioning surgery by considering different materials and designs. METHODS: All published studies investigating the repositioning surgery of toric intraocular lenses (IOLs) before September 1, 2020, were searched and evaluated. The R3.5.2 software was used to extract the data, and a single arm meta-analysis was performed. RESULTS: 19 cases from 18 published studies articles were included in the meta-analysis. The pooled incidence rate in repositioning surgery was 2% (I 2 = 53%, P heterogeneity<0.01). Plate and silicone IOLs had significantly higher incidence rates (6% for each) than loop (2%) and hydrophobic acrylate (2%). Incidence rates of Acrysof, Staar, TECNIS, PhysIOL SA, T-flex 623T, and Microsil 6116TU groups were 1% (95% CI [1%-2%]), 6% (95% CI [4%-9%]), 3% (95% CI [2%-4%]), 1.40% (1/71), 3.03% (1/33), and 4.76% (1/21), respectively. CONCLUSIONS: The pooled incidence rate of repositioning surgery in IOLs was 2%. Materials and designs would be risk factors for the rotational stability of the toric IOLs. Pooled incidence rates of the hydrophobic acrylate and loop group were lower than those of the silicone and plate group. Product identity is the main driver of heterogeneity.

17.
Artículo en Inglés | MEDLINE | ID: mdl-36011836

RESUMEN

Thirty samples of surface sediments (0-5 cm) from the northern Beibu Gulf were analyzed to determine the spatial distribution, potential risks and sources of six heavy metals (Cr, Cu, Zn, As, Cd and Pb). The concentrations (mg/kg, dw) of Cr, Cu, Zn, As, Cd and Pb were 15.38 ± 6.06, 6.54 ± 3.23, 41.86 ± 17.03, 6.92 ± 2.75, 0.04 ± 0.02 and 17.13 ± 6.38, respectively. Higher levels of Cr, Cu, Cd and Zn were observed in the western part of the study area. According to the potential ecological risk indexes and sediment quality guidelines, the measured metals were assessed at low contamination levels, with Pb posing the largest ecological risks. The results of positive matrix factorization (PMF) indicated that Cr and Zn mainly originated from natural geological background sources, while Cu, As, Cd and Pb were influenced by anthropogenic sources such as atmospheric deposition and anthropogenic activities. These three sources contributed 60.4%, 28.1% and 11.5% of the heavy metals, respectively. In addition, further research should be conducted focusing on the general relationships between As and various controls in sediments of the northern Beibu Gulf.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Cadmio , China , Monitoreo del Ambiente , Sedimentos Geológicos , Plomo , Metales Pesados/análisis , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
18.
Innovation (Camb) ; 3(2): 100217, 2022 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-35243471

RESUMEN

Based on predictable, complementary base pairing, DNA can be artificially pre-designed into versatile DNA nanostructures of well-defined shapes and sizes. With excellent addressability and biocompatibility, DNA nanostructures have been widely employed in biomedical research, such as bio-sensing, bio-imaging, and drug delivery. With the development of the chemical biology of nucleic acid, chemically modified nucleic acids are also gradually developed to construct multifunctional DNA nanostructures. In this review, we summarize the recent progress in the construction and functionalization of chemically modified DNA nanostructures. Their applications in the delivery of chemotherapeutic drugs and nucleic acid drugs are highlighted. Furthermore, the remaining challenges and future prospects in drug delivery by chemically modified DNA nanostructures are discussed.

19.
Mitochondrial DNA B Resour ; 7(1): 277-279, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35097215

RESUMEN

The complete mitochondrial genome of the Cephalopholis urodeta (Serranidae: Epinephelinae) was sequenced by next-generation sequencing method on the basis of one female specimen collected from coral reef areas at the Mischief Reef, South China Sea. The mitogenome is 16,593 bp in length, including 13 protein-coding genes, 22 tRNA genes, two rRNA genes and a D-loop region. The overall content of A + T is 55.66%, which is significantly higher than the C + G content (44.34%). Among four bases, C shows the lowest frequency (15.99%). Phylogenetic tree based on the 13 protein-coding genes was constructed for analyzing the position of C. urodeta. The results provide useful insights into further studies on population genetics and phylogenetics of groupers.

20.
Mitochondrial DNA B Resour ; 7(1): 180-181, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35028412

RESUMEN

In the present study, the complete mitogenome of Cephaloscyllium fasciatum has been sequenced and assembled. The complete mitochondrial genome is 16,509 bp in length and contains 37 mitochondrial genes and a control region as other fishes. The nucleotide composition of C. fasciatum mitogenome showed an anti-G bias and an excess of AT content. Furthermore, maximum-likelihood phylogenetic tree was constructed based on 13 protein-coding genes of C. fasciatum and other 15 sharks. This work will provide molecular data for studies on phylogeny and evolution in the family Scyliorhinidae.

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