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1.
Mol Biol Evol ; 41(7)2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38842255

RESUMEN

The origins and extreme morphological evolution of the modern dog breeds are poorly studied because the founder populations are extinct. Here, we analyse eight 100 to 200 years old dog fur samples obtained from traditional North Swedish clothing, to explore the origin and artificial selection of the modern Nordic Lapphund and Elkhound dog breeds. Population genomic analysis confirmed the Lapphund and Elkhound breeds to originate from the local dog population, and showed a distinct decrease in genetic diversity in agreement with intense breeding. We identified eleven genes under positive selection during the breed development. In particular, the MSRB3 gene, associated with breed-related ear morphology, was selected in all Lapphund and Elkhound breeds, and functional assays showed that a SNP mutation in the 3'UTR region suppresses its expression through miRNA regulation. Our findings demonstrate analysis of near-modern dog artifacts as an effective tool for interpreting the origin and artificial selection of the modern dog breeds.


Asunto(s)
Pelaje de Animal , Selección Genética , Animales , Perros/genética , Polimorfismo de Nucleótido Simple , Cruzamiento , Suecia , Variación Genética , MicroARNs/genética
2.
J Am Chem Soc ; 145(31): 17164-17175, 2023 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-37440344

RESUMEN

One of the hallmarks of multicomponent metal-organic frameworks (MOFs) is to finely tune their active centers to achieve product selectivity. In particular, obtaining bimetallic MOF hollow structures with precisely tailored redox centers under the same topology is still challenging despite a recent surge of such efforts. Herein, we present an engineering strategy named "cluster labilization" to generate hierarchically porous MOF composites with hollow structures and tunable active centers. By partially replacing zirconium with cerium in the hexanuclear clusters of UiO-66, unevenly distributed yolk-shell structures (YSS) were formed. Through acid treatment or annealing of the YSS precursor, single-shell hollow structures (SSHS) or double-shell hollow structures (DSHS) can be obtained, respectively. The active centers in SSHS and DSHS differ in their species, valence, and spatial locations. More importantly, YSS, SSHS, and DSHS with distinct active centers and microenvironments exhibit tunable catalytic activity, reversed selectivity, and high stability in the tandem reaction and the photoreaction.

3.
Opt Express ; 30(21): 39142-39151, 2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36258461

RESUMEN

Water-based coherent detection of broadband terahertz (THz) wave has been recently proposed with superior performances, which can alleviate the limited detection bandwidth and high probe laser energy requirement in the solid- and air-based detection schemes, respectively. Here, we demonstrate that the water-based detection method can be extended to the aqueous salt solutions and the sensitivity can be significantly enhanced. The THz coherent detection signal intensity scales linearly with the third-order nonlinear susceptibility χ(3) or quadratically with the linear refractive index η0 of the aqueous salt solutions, while the incoherent detection signal intensity scales quadratically with χ(3) or quartically with η0, proving the underlying mechanism is the four-wave mixing. Both the coherent and incoherent detection signal intensities appear positive correlation with the solution concentration. These results imply that the liquid-based THz detection scheme could provide a new technique to measure χ(3) and further investigate the physicochemical properties in the THz band for various liquids.

4.
Phys Rev Lett ; 128(9): 093902, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35302828

RESUMEN

Both solids and gases have been demonstrated as the materials for terahertz (THz) coherent detection. The gas-based coherent detection methods require a high-energy probe laser beam and the detection bandwidth is limited in the solid-based methods. Whether liquids can be used for THz detection and relax these problems has not yet been reported, which becomes a timely and interesting topic due to the recent observation of efficient THz wave generation in liquids. Here, we propose a THz coherent detection scheme based on liquid water. When a THz pulse and a fundamental laser beam are mixed on a free-flowing water film, a second harmonic (SH) beam is generated as the plasma is formed. Combining this THz-induced SH beam with a control SH beam, we successfully achieve the time-resolved waveform of the THz field with the frequency range of 0.1-18 THz. The required probe laser energy is as low as a few microjoules. The sensitivity of our scheme is 1 order of magnitude higher than that of the air-based method under comparable detection conditions. The scheme is sensitive to the THz polarization and the phase difference between the fundamental and control SH beams, which brings direct routes for optimization and polarization sensitive detection. Energy scaling and polarization properties of the THz-induced beam indicate that its generation can be attributed to a four-wave mixing process. This generation mechanism makes simple relationships among the probe laser, THz-induced SH, and THz field, favorable for robustness and flexibility of the detection device.

5.
Opt Express ; 28(6): 7843-7857, 2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32225420

RESUMEN

The effect of the growth of ambient pressures on the penetration of laser welded molybdenum (Mo) alloy was explored. It was found that when ambient pressure rose from 0.1 MPa to 1.8 MPa, the penetration of base metal (BM) was significantly reduced, which was only 17% of that obtained under ambient pressure of 0.1 MPa. Moreover, the mechanism underlying the significant reduction of the penetration of BM was analyzed. At first, by using a high-resolution scanning electron microscope (SEM), the size and the number of nano-sized metallic particles generated during laser welding under different ambient pressures were surveyed. Furthermore, the scattering and absorption of the nano-sized metallic particles for laser energy under different ambient pressures were investigated; afterwards, by applying a high-speed camera and a spectrometer, the transient behaviors and spectral signals of plasmas during fiber laser spot welding under different ambient pressures were monitored. On this basis, the inverse bremsstrahlung absorption of plasmas for laser energy under different ambient pressures was explored; finally, fiber laser spot welding test was carried out on glass/metal composite samples under different ambient pressures to survey the influence of the change of ambient pressure on dynamic behaviors of the molten pool during the welding.

6.
J Am Chem Soc ; 140(6): 2363-2372, 2018 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-29345141

RESUMEN

Sufficient pore size, appropriate stability, and hierarchical porosity are three prerequisites for open frameworks designed for drug delivery, enzyme immobilization, and catalysis involving large molecules. Herein, we report a powerful and general strategy, linker thermolysis, to construct ultrastable hierarchically porous metal-organic frameworks (HP-MOFs) with tunable pore size distribution. Linker instability, usually an undesirable trait of MOFs, was exploited to create mesopores by generating crystal defects throughout a microporous MOF crystal via thermolysis. The crystallinity and stability of HP-MOFs remain after thermolabile linkers are selectively removed from multivariate metal-organic frameworks (MTV-MOFs) through a decarboxylation process. A domain-based linker spatial distribution was found to be critical for creating hierarchical pores inside MTV-MOFs. Furthermore, linker thermolysis promotes the formation of ultrasmall metal oxide nanoparticles immobilized in an open framework that exhibits high catalytic activity for Lewis acid-catalyzed reactions. Most importantly, this work provides fresh insights into the connection between linker apportionment and vacancy distribution, which may shed light on probing the disordered linker apportionment in multivariate systems, a long-standing challenge in the study of MTV-MOFs.

8.
Phys Rev Lett ; 119(23): 235001, 2017 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-29286697

RESUMEN

In the widely studied two-color laser scheme for terahertz (THz) radiation from a gas, the frequency ratio of the two lasers is usually fixed at ω_{2}/ω_{1}=1:2. We investigate THz generation with uncommon frequency ratios. Our experiments show, for the first time, efficient THz generation with new ratios of ω_{2}/ω_{1}=1:4 and 2∶3. We observe that the THz polarization can be adjusted by rotating the longer-wavelength laser polarization and the polarization adjustment becomes inefficient by rotating the other laser polarization; the THz energy shows similar scaling laws with different frequency ratios. These observations are inconsistent with multiwave mixing theory, but support the gas-ionization or plasma-current model. This study pushes the development of the two-color scheme and provides a new dimension to explore the long-standing problem of the THz generation mechanism.

9.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 346-9, 2017 Feb.
Artículo en Zh | MEDLINE | ID: mdl-30264959

RESUMEN

As emerging modalities, terahertz time-domain spectroscopy and imaging have been widely applied to investigate the optical properties of different biological tissues. The substrate materials are usually needed for biological spectroscopic measurements. The ultra-broadband and facility in remote sensing of the terahertz air-biased-coherent-detection (ABCD) system mean it is a good potential tool for the spectroscopic study of biological tissues. In this paper, the optical parameters of four typical substrate materials (quartz, high-density polyethylene, teflon and paraffin) are measured using terahertz ABCD spectrometer. The absorption coefficients and refractive indices are presented in the frequency range of 1~15 THz. It is demonstrated that high-density polyethylene and paraffin are good candidates as sample substrate for broadband terahertz biological spectroscopic measurement. However, quartz and teflon which are common substrate materials in narrowband (0.1~3 THz) terahertz system can not be utilized in high terahertz frequency range because they have strong absorption above 5 THz.


Asunto(s)
Espectroscopía de Terahertz , Refractometría
10.
Artículo en Zh | MEDLINE | ID: mdl-30133234

RESUMEN

Objective: To record the discovery of Culex inatomii in Chongming, Shanghai. Methods: Larvae and adult mosquitos of Cx. inatomii were collected in Dongtan of Chongming Island from May to November in 2015 and 2016, and their morphological characteristics were observed. The genomic DNA was extracted from adult mosquitos, PCR was performed to amplify the cytochrome c oxidaseⅠ(COⅠ) gene. Multiple alignment of COⅠ sequence was conducted with ClustalW2. Pairwise distances within and between species were calculated using MEGA v5.10 based on COⅠ sequences of Cx. inatomii, Cx. modestus, Cx. pipiens pallens, and Cx. tritaeniorhynchus. The phylogenetic tree of the above four species was constructed using neighbor joining, maximum likelihood, and Bayesian methods. Results: One hundred and fifty-six adult female mosquitos and 36 larvae of Cx. inatomii were collected. Larvae were reared to adult stage in the laboratory (17 female, 19 male). Morphologically, the subapical lobe of the sidepiece in male genitalia was divided into two parts, the anterior part having 2 bladed setae, and the posterior part having 1 bladed setae and 1 lanceolar strong setae. This strucutre can be used to distinguish Cx. inatomii from Cx. modestus. PCR of COⅠ resulted in products of approximately 650 bp. They were sequenced and the sequencing result was submitted to GenBank (accession number, KX555565-KX555570). Multiple sequence alignment revealed a 96% sequence similarity of COⅠ between Cx. inatomii and Cx. modestus. The genetic distance between Cx. inatomii and Cx. modestus was 0.047, and that within them each was 0.003 and 0.011, respectively. The phylogenetic tree showed that the four species clustered as a monophyletic clade, and each formed an individual lineage. Cx. inatomii had a closer relationship with Cx. modestus, while distant from the other two species. Conclusion: We recorded the discovery of Cx. inatomii in Chongming, Shanghai.


Asunto(s)
Culex , Animales , Teorema de Bayes , China , Femenino , Larva , Masculino , Filogenia , Alineación de Secuencia
11.
Guang Pu Xue Yu Guang Pu Fen Xi ; 36(2): 322-5, 2016 Feb.
Artículo en Zh | MEDLINE | ID: mdl-27209723

RESUMEN

Indium Phosphide (InP) has attracted great physical interest because of its unique characteristics and is indispensable to both optical and electronic devices. However, the optical property of InP in the terahertz range (0. 110 THz) has not yet been fully characterized and systematically studied. The former researches about the properties of InP concentrated on the terahertz frequency between 0.1 and 4 THz. The terahertz optical properties of the InP in the range of 4-10 THz are still missing. It is fairly necessary to fully understand its properties in the entire terahertz range, which results in a better utilization as efficient terahertz devices. In this paper, we study the optical properties of undoped (100) InP wafer in the ultra-broad terahertz frequency range (0.5-18 THz) by using air-biased-coherent-detection (ABCD) system, enabling the coherent detection of terahertz wave in gases, which leads to a significant improvement on the dynamic range and sensitivity of the system. The advantage of this method is broad frequency bandwidth from 0.2 up to 18 THz which is only mainly limited by laser pulse duration since it uses ionized air as terahertz emitter and detector instead of using an electric optical crystal or photoconductive antenna. The terahertz pulse passing through the InP wafer is delayed regarding to the reference pulse and has much lower amplitude. In addition, the frequency spectrum amplitude of the terahertz sample signal drops to the noise floor level from 6.7 to 12.1 THz. At the same time InP wafer is opaque at the frequencies spanning from 6.7 to 12.1 THz. In the frequency regions of 0.8-6.7 and 12.1-18 THz it has relativemy low absorption coefficient. Meanwhile, the refractive index increases monotonously in the 0.8-6.7 THz region and 12.1-18 THz region. These findings will contribute to the design of InP based on nonlinear terahertz devices.

12.
Anal Chem ; 86(3): 1808-15, 2014 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-24417222

RESUMEN

The ability to detect spatial and temporal microRNA (miRNA) distribution at the single-cell level is essential for understanding the biological roles of miRNAs and miRNA-associated gene regulatory networks. We report for the first time the development of a target-primed RCA (TPRCA) strategy for highly sensitive and selective in situ visualization of miRNA expression patterns at the single-cell level. This strategy uses a circular DNA as the probe for in situ hybridization (ISH) with the target miRNA molecules, and the free 3' terminus of miRNA then initiates an in situ RCA reaction to generate a long tandem repeated sequence with thousands of complementary segments. After hybridization with fluorescent detection probes, target miRNA molecules can be visualized with ultrahigh sensitivity. Because the RCA reaction can only be initiated by the free 3' end of target miRNA, the developed strategy offers the advantage over existing ISH methods in eliminating the interference from precursor miRNA or mRNA. This strategy is demonstrated to show high sensitivity and selectivity for the detection of miR-222 expression levels in human hepatoma SMMC-7721 cells and hepatocyte L02 cells. Moreover, the developed TPRCA-based ISH strategy is successfully applied to multiplexed detection using two-color fluorescent probes for two miRNAs that are differentially expressed in the two cell lines. The results reveal that the developed strategy may have great potential for in situ miRNA expression analysis for basic research and clinical diagnostics.


Asunto(s)
Cartilla de ADN/genética , Hibridación Fluorescente in Situ/métodos , MicroARNs/genética , MicroARNs/metabolismo , Técnicas de Amplificación de Ácido Nucleico/métodos , Secuencia de Bases , Línea Celular Tumoral , Color , Regulación Neoplásica de la Expresión Génica , Humanos , Imagen Molecular , Análisis Espacio-Temporal
13.
Artículo en Zh | MEDLINE | ID: mdl-25223053

RESUMEN

OBJECTIVE: To clone and express the aegyptin-like protein (alALP) encoding gene from Aedes albopictus salivary gland, and analyze its antigenicity. METHODS: The homology, secondary structure and antigen peptides of alALP and aegyptin protein (GenBank No. ABF18122.1) was analyzed by bioinformatics software tools. Total RNA was extracted from Ae. albopictus salivary gland. The coding region of alALP (GenBank No. AY826121) was amplified by PCR. RT-PCR product was digested with restriction enzyme and ligated into a pGEX-6P-1 vector. The recombinant pGEX-6P-1-alALP plasmid was transformed into E. coli BL21 and induced by IPTG. The recombinant soluble GST-alALP fusion protein was purified with Glutathione Sepharose 4B. The expression product was analyzed by SDS-PAGE and Western blotting. Mice were immunized each with 60 microg purified GST-alALP at every 2 weeks for 3 times, and mouse anti-GST-alALP serum was prepared. Western blotting assay with mice anti-GST-alALP serum and serum of mice exposed to Ae. albopictus bites was used to analyze its antigenicity. RESULTS: Bioinformatics prediction results showed that alALP and aegyptin had 65.58% homology with a similar secondary structure, and a conservative polypeptide. The product of RT-PCR was 762 bp. The recombinant plasmid pGEX-6P-1-alALP was confirmed by double restriction enzyme digestion, PCR and sequencing. SDS-PAGE and Western blotting analysis showed that the bacteria containing recombinant plasmid pGEX-6p-1-alALP expressed a soluble recombinant fusion protein (M(r) 56 000) after being induced with IPTG. Western blotting analysis revealed that GST-alALP protein was recognized by mouse anti-GST-alALP serum and serum of mice ex- posed to Ae. albopictus bites. CONCLUSION: Mature peptide gene of alALP can be expressed in prokaryotic expression system, and the recombinant protein shows antigenicity.


Asunto(s)
Aedes/inmunología , Antígenos/inmunología , Proteínas de Insectos/inmunología , Proteínas y Péptidos Salivales/inmunología , Animales , Western Blotting , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Expresión Génica , Vectores Genéticos , Ratones , Plásmidos , Reacción en Cadena de la Polimerasa , Proteínas Recombinantes/inmunología
14.
Chem Commun (Camb) ; 59(18): 2541-2559, 2023 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-36749364

RESUMEN

Recently, Zr- and Ti-based metal-organic frameworks (MOFs) have gathered increasing interest in the field of chemistry and materials science, not only for their ordered porous structure, large surface area, and high thermal and chemical stability, but also for their various potential applications. Particularly, the unique features of Zr- and Ti-based MOFs enable them to be a highly versatile platform for catalysis. Although much effort has been devoted to developing Zr- and Ti-based MOF materials, they still suffer from difficulties in targeted synthesis, especially for Ti-based MOFs. In this Feature Article, we discuss the evolution of Zr- and Ti-based MOFs, giving a brief overview of their synthesis and structures. Furthermore, the catalytic uses of Zr- and Ti-based MOF materials in the previous 3-5 years have been highlighted. Finally, perspectives on the Zr- and Ti-based MOF materials are also proposed. This work provides in-depth insight into the advances in Zr- and Ti-based MOFs and boosts their catalytic applications.

15.
Front Neurol ; 14: 1187813, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37602242

RESUMEN

Gerstmann-Sträussler-Scheinker syndrome (GSS) is a rare genetic prion disease caused by a mutation in the prion protein (PRNP) gene. It is typically characterized by progressive cerebellar ataxia and slowly progressive dementia. We present a case study of the GSS from China in which a 45-year-old male with a progressive gait and balance disorder developed cerebellar ataxia onset but was misdiagnosed as spinocerebellar ataxia (SCA) for 2 years. The patient's clinical, electrophysiological, and radiological data were retrospectively analyzed. Examination revealed ataxia, dysarthria, muscle weakness, areflexia in lower limbs, including a pyramidal sign, whereas cognitive decline was insignificant. His late mother had a similar unsteady gait. An electroencephalogram (EEG) showed normal findings, and 14-3-3 protein was negative. A brain MRI was performed for global brain atrophy and ventricular enlargement. Positron emission tomography-computed tomography (PET-CT) (18F-fluoro-2-deoxy-d-glucose, FDG) images showed mild to moderate decreased glucose metabolism in the left superior parietal lobe and left middle temporal lobe. According to genetic testing, his younger brother also had the P102L variant in the PRNP gene. This single case adds to the clinical and genetic phenotypes of GSS.

16.
World J Clin Cases ; 10(14): 4535-4540, 2022 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-35663070

RESUMEN

BACKGROUND: Regular abdominal massage can be used to treat digestive symptoms such as bloating and constipation and is reported to reduce abdominal discomfort, improve digestive function, and increase the quality of life, without serious adverse effects. Isolated pancreatic injury is rare, and most often occurs during severe trauma such as steering wheel impact injury. To our knowledge, pancreatic injury caused by massage has not yet been reported in the literature. CASE SUMMARY: A 57-year-old woman was referred to our hospital for acute abdominal pain and transient syncope. On examination, she had low hemoglobin concentration and a high white blood cell count and neutrophil percentage. Plain computed tomography of the abdomen revealed a substantial hemorrhage in the abdominal cavity. A large amount of exudate in the pancreatic area was considered a hematoma. Preoperative diagnosis was difficult. Her hemoglobin and blood pressure did not rise even after blood. We suspected progressive bleeding in the abdominal cavity and urgently performed exploratory laparotomy. During the operation, the pancreas was confirmed to be ruptured; hence, spleen-preserving pancreatic body and tail resection were performed. A pancreatic fistula was found on the 15th d after the operation, and the patient was discharged with a drainage tube on the 24th d after active treatment. Subsequently, it was discovered that the patient had undergone a vigorous abdominal massage the day before the abdominal pain began. To our knowledge, this is the first report of isolated pancreatic injury and massive abdominal hemorrhage caused by abdominal massage. CONCLUSION: Our findings indicate that any action that increases intra-abdominal pressure may cause internal organ damage. We also review similar cases reported in the literature.

17.
Chemosphere ; 297: 134215, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35248597

RESUMEN

In this work, a desulfurization method using natural amino acid salts (AAS), which can be green prepared by biological fermentation, is proposed to remove H2S from raw biogas. Biogas purification and fertilizer production can be simultaneously achieved to close sulfur recycle. The reaction kinetic characteristics of H2S absorption with three kinds of AAS, including potassium ß-alaninate (PA), potassium sarcosinate (PS) and potassium l-prolinate (PP) are first studied. Kinetic parameters including orders of reaction, rate constants, pre-exponential factors and activation energies are given. AAS absorbent exhibits good potential for biogas desulfurization. Higee (high gravity) technology is utilized to intensify H2S removal. The effects of operating conditions on H2S removal efficiency are investigated and PP shows the best desulfurization performance. The phytotoxicity of AAS and amino acid salt sulfide (AASS) is assessed by the germination index of mungbean seeds. PP and its salt sulfide (PPS) show relatively low phytotoxicity and their allowable agricultural feeding concentrations are below 0.08 M and 0.04 M, respectively. The desulfurization method demonstrates a green route for biogas purification to achieve sulfur recycle.


Asunto(s)
Biocombustibles , Sulfuro de Hidrógeno , Aminoácidos , Reactores Biológicos , Sulfuro de Hidrógeno/química , Potasio , Sales (Química) , Sulfuros , Azufre/metabolismo
18.
ACS Appl Mater Interfaces ; 14(2): 3476-3484, 2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34985879

RESUMEN

Supports can widely affect or even dominate the catalytic activity and selectivity of nanoparticles because atomic geometry and electronic structures of active sites can be regulated, especially at the interface of nanoparticles and supports. However, the underlying mechanisms of most systems are still not fully understood yet. Herein, we construct the interface of Co3O4/TiO2 to boost ammonium perchlorate (AP) catalytic decomposition. This catalyst shows enhanced catalytic performance. With the addition of 2 wt % Co3O4/TiO2 catalysts, AP decomposition peak temperature decreases from 435.7 to 295.0 °C and activation energy decreases from 211.5 to 137.7 kJ mol-1. By combining experimental and theoretical studies, we find that Co3O4 nanoparticles can be strongly anchored onto TiO2 supports accompanied by charge transfer. Moreover, at the interfaces in the Co3O4/TiO2 nanostructure, NH3 adsorption can be enhanced through hydrogen bonds. Our research studies provide new insights into the promotion effects of the nanoparticle/support system on the AP decomposition process and inspire the design of efficient catalysts.

19.
Dalton Trans ; 51(15): 5782-5787, 2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35353878

RESUMEN

A triphenylphosphine-modified tetra-nuclear Cu(I) coordinated cluster was constructed for enhanced chemodynamic therapy (CDT) by increasing the number of metal centers. Once inside human bladder cancer (T24) cells, a larger amount of copper accumulated compared with the mono-nuclear Cu(I) complex; the additional copper could generate more •OH and then induce more obvious apoptosis via a Fenton-like reaction, thus further increasing the tumor inhibition effect and ultimately improving the CDT efficiency.


Asunto(s)
Cobre , Neoplasias , Línea Celular Tumoral , Humanos , Peróxido de Hidrógeno , Compuestos Organofosforados
20.
Anal Chem ; 83(1): 14-7, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21117628

RESUMEN

This work reports the development of a new molecular beacon-based junction sensing system with highly sensitive DNA detection and a strong capability to identify SNPs. The single linear probe typically labels the midsection of the oligonucleotide, but our next-generation junction sensing system uses a hairpin-structured MB with labels on each end of the oligonucleotide to maintain the cleaving activity of our newly designed ssDNA-cleaved endonuclease, Nt.BbvCI, rather than the typical dsDNA-cleaved endonuclease. These design improvements guarantee a true and efficient target-triggered enzymatic recycling amplification process in our sensing system. They also afford a faster and more sensitive response toward target DNA than the first-generation junction sensing system.


Asunto(s)
Técnicas Biosensibles/métodos , ADN/análisis , ADN/genética , Desoxirribonucleasa I/metabolismo , Técnicas de Amplificación de Ácido Nucleico/métodos , Sondas de Oligonucleótidos/química , Sondas de Oligonucleótidos/genética , Secuencia de Bases , ADN/metabolismo , Sondas de Oligonucleótidos/metabolismo
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