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1.
Nature ; 628(8009): 741-745, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38658686

RESUMEN

Extensive efforts have been undertaken to combine superconductivity and the quantum Hall effect so that Cooper-pair transport between superconducting electrodes in Josephson junctions is mediated by one-dimensional edge states1-6. This interest has been motivated by prospects of finding new physics, including topologically protected quasiparticles7-9, but also extends into metrology and device applications10-13. So far it has proven challenging to achieve detectable supercurrents through quantum Hall conductors2,3,6. Here we show that domain walls in minimally twisted bilayer graphene14-18 support exceptionally robust proximity superconductivity in the quantum Hall regime, allowing Josephson junctions to operate in fields close to the upper critical field of superconducting electrodes. The critical current is found to be non-oscillatory and practically unchanging over the entire range of quantizing fields, with its value being limited by the quantum conductance of ballistic, strictly one-dimensional, electronic channels residing within the domain walls. The system described is unique in its ability to support Andreev bound states at quantizing fields and offers many interesting directions for further exploration.

2.
Nature ; 616(7956): 270-274, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37045919

RESUMEN

The most recognizable feature of graphene's electronic spectrum is its Dirac point, around which interesting phenomena tend to cluster. At low temperatures, the intrinsic behaviour in this regime is often obscured by charge inhomogeneity1,2 but thermal excitations can overcome the disorder at elevated temperatures and create an electron-hole plasma of Dirac fermions. The Dirac plasma has been found to exhibit unusual properties, including quantum-critical scattering3-5 and hydrodynamic flow6-8. However, little is known about the plasma's behaviour in magnetic fields. Here we report magnetotransport in this quantum-critical regime. In low fields, the plasma exhibits giant parabolic magnetoresistivity reaching more than 100 per cent in a magnetic field of 0.1 tesla at room temperature. This is orders-of-magnitude higher than magnetoresistivity found in any other system at such temperatures. We show that this behaviour is unique to monolayer graphene, being underpinned by its massless spectrum and ultrahigh mobility, despite frequent (Planckian limit) scattering3-5,9-14. With the onset of Landau quantization in a magnetic field of a few tesla, where the electron-hole plasma resides entirely on the zeroth Landau level, giant linear magnetoresistivity emerges. It is nearly independent of temperature and can be suppressed by proximity screening15, indicating a many-body origin. Clear parallels with magnetotransport in strange metals12-14 and so-called quantum linear magnetoresistance predicted for Weyl metals16 offer an interesting opportunity to further explore relevant physics using this well defined quantum-critical two-dimensional system.

3.
Mol Biol Rep ; 51(1): 114, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227268

RESUMEN

BACKGROUND: The production of interferons (IFNs) is essential for the control of viral infections, and interferon regulatory factor 7 (IRF7) is considered as a vital regulator for the transcription of type I IFNs. Amphibians appear to possess a highly expanded type I IFN repertoire, consisting of intron-containing genes as observed in fish, and intronless genes as in other higher vertebrates. However, the knowledge on transcriptional regulatory mechanism of these two types of type I IFN genes is rather scarce in amphibians. METHODS AND RESULTS: A IRF7 gene named as Np-IRF7 was identified in Tibetan frog (Nanorana parkeri), and bioinformatic analysis revealed that the predicted protein of Np-IRF7 contains several important structural features known in IRF7. Expression analysis showed that Np-IRF7 gene was widely expressed and rapidly induced by poly(I:C) in different organs/tissues. Interestingly, luciferase reporter assay revealed that intronless IFN promoters were more effectively activated than intron-containing IFN promoter in Np-IRF7-transfected cells. Moreover, the overexpression of Np-IRF7 could induce the expression of ISGs and suppress the replication of FV3 in A6 cells. CONCLUSION: Np-IRF7 is indeed the ortholog of known IRF7, and IRF7 is structurally conserved in different lineages of vertebrates. Np-IRF7 played distinct roles in the activation of intron-containing and intronless type I IFN promoters, thus inducing the expression of interferon-stimulated antiviral effectors and providing a protection against ranavirus infection. The present research thus contributes to a better understanding of regulatory function of IRF7 in the IFN-mediated antiviral response of anuran amphibians.


Asunto(s)
Factor 7 Regulador del Interferón , Interferón Tipo I , Animales , Humanos , Factor 7 Regulador del Interferón/genética , Tibet , Anuros/genética , Intrones/genética , Interferón Tipo I/genética
4.
Clin Oral Implants Res ; 35(4): 427-442, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38314615

RESUMEN

OBJECTIVE: This study aimed to synthesize zinc-incorporated nanowires structure modified titanium implant surface (Zn-NW-Ti) and explore its superior osteogenic and antibacterial properties in vitro and in vivo. MATERIALS AND METHODS: Zn-NW-Ti was synthesized via displacement reactions between zinc sulfate solutions and the titanium (Ti) surface, which was pretreated by hydrofluoric acid etching and hyperthermal alkalinization. The physicochemical properties of the Zn-NW-Ti surface were examined. Moreover, the biological effects of Zn-NW-Ti on MC3T3-E1 cells and its antibacterial property against oral pathogenic bacteria (Staphylococcus aureus, Porphyromonas gingivalis, and Actinobacillus actinomycetemcomitans) compared with sandblasted and acid-etched Ti (SLA-Ti) and nanowires modified Ti (NW-Ti) surface were assessed. Zn-NW-Ti and SLA-Ti modified implants were inserted into the anterior extraction socket of the rabbit mandible with or without exposure to the mixed bacterial solution (S. aureus, P. gingivalis, and A. actinomycetemcomitans) to investigate the osteointegration and antibacterial performance via radiographic and histomorphometric analysis. RESULTS: The Zn-NW-Ti surface was successfully prepared. The resultant titanium surface appeared as a nanowires structure with hydrophilicity, from which zinc ions were released in an effective concentration range. The Zn-NW-Ti surface performed better in facilitating the adhesion, proliferation, and differentiation of MC3T3-E1 cells while inhibiting the colonization of bacteria compared with SLA-Ti and NW-Ti surface. The Zn-NW-Ti implant exhibited enhanced osseointegration in vivo, which was attributed to increased osteogenic activity and reduced bacterial-induced inflammation compared with the SLA-Ti implant. CONCLUSIONS: The Zn-incorporated nanowires structure modified titanium implant surface exhibited improvements in osteogenic and antibacterial properties, which optimized osteointegration in comparison with SLA titanium implant surface.


Asunto(s)
Implantes Dentales , Nanocables , Animales , Conejos , Titanio/farmacología , Titanio/química , Staphylococcus aureus , Antibacterianos/farmacología , Oseointegración , Bacterias , Zinc/química , Zinc/farmacología , Propiedades de Superficie , Osteogénesis
5.
Can J Infect Dis Med Microbiol ; 2024: 6698387, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38361762

RESUMEN

To evaluate the prevalence and quality of antimicrobial prescriptions using a Global Point Prevalence Survey (PPS) tool and help identify targets for improvement of antimicrobial prescribing and inform the development of antimicrobial stewardship activities. Antimicrobial prescriptions for inpatients staying at a hospital overnight were surveyed on one weekday in October 2018, November 2019, and November 2020. Data including basic patient information, antimicrobial drugs, quality evaluation of antimicrobial drug prescription, and the risk factors of nosocomial infection were collected from doctor network workstation. Patient information was anonymized and entered in the PPS Web application by physicians. A total of 720 patients (median age, 62 years) were surveyed. Of them, 246 (34.2%) were prescribed antimicrobials on the survey days. Hospital-wide antimicrobial use had a significantly decreasing trend (P < 0.001). The most commonly prescribed antimicrobial drugs were third-generation cephalosporins (40.5%), followed by quinolones (21.8%) and second-generation cephalosporin (12.5%). In our study, cefoperazone/sulbactam, ceftazidime, and levofloxacin were the most commonly used antimicrobials. The most common indication for antimicrobial use was pneumonia or lower respiratory tract infection (159/321, 49.5%). Antimicrobial for surgical prophylaxis represented 16.2% of the total antibiotic doses. Of those, 67.3% were administered for more than 24 h. The rate of adherence to antibiotic guidelines was 61.4%. The indications for antimicrobials were not documented in 54.5% of the prescriptions. Stop/review date was documented for 36.8% of prescriptions. The PPS tool is useful in identifying targets to enhance the quality of antimicrobial prescriptions to improve the adherence rate in hospitals. This survey can be used as a control to assess the rational application quality of antimicrobial after regular application of antimicrobial intervention.

6.
Int Microbiol ; 2023 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-38062211

RESUMEN

Aeromonas salmonicida is the typical pathogen causing furunculosis, reported widely in salmonids. Because of multiple serotypes, the control of A. salmonicida-caused disease has increasingly received much attention. Recently, A. salmonicida infection was reported in non-salmonid fish species. Here, a pathogenic A. salmonicida, named as As-s, was isolated from cultured snakehead (Channa argus) in a local fish farm in Shandong, China. As-s displayed clear hemolysis, amylase, and positive catalase activities, and grew at a wide range of temperatures (10-37 °C) and pH values (5.5-8.5). As-s was highly sensitive to cefuroxime sodium, ceftriaxone, ceftazidime, piperacillin, and cefoperazone and also apparently sensitive to chloramphenicol, erythromycin, and 25% cinnamaldehyde. The Virulence array protein gene cloning' results suggested that As-s has this gene compared with the other two vapA-containing strains, despite a close relationship of these strains via phylogenetic analysis. Severe ulcers on skin, muscle, and abnormal liver, and hemorrhage in pectoral/ventral fins and anal region were observed, and exophthalmos were also noticed in infected juvenile snakehead, as well as necrosis and infiltration of blood cells emerged in the internal organs using pathological section. In addition, As-s caused high mortality in snakehead, consistently with its immune gene response. This study reports the first isolation of vapA-absent A. salmonicida in snakehead.

7.
J Nanobiotechnology ; 21(1): 194, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37322478

RESUMEN

BACKGROUND: Polarization of microglia, the resident retinal immune cells, plays important roles in mediating both injury and repair responses post-retinal ischemia-reperfusion (I/R) injury, which is one of the main pathological mechanisms behind ganglion cell apoptosis. Aging could perturb microglial balances, resulting in lowered post-I/R retinal repair. Young bone marrow (BM) stem cell antigen 1-positive (Sca-1+) cells have been demonstrated to have higher reparative capabilities post-I/R retinal injury when transplanted into old mice, where they were able to home and differentiate into retinal microglia. METHODS: Exosomes were enriched from young Sca-1+ or Sca-1- cells, and injected into the vitreous humor of old mice post-retinal I/R. Bioinformatics analyses, including miRNA sequencing, was used to analyze exosome contents, which was confirmed by RT-qPCR. Western blot was then performed to examine expression levels of inflammatory factors and underlying signaling pathway proteins, while immunofluorescence staining was used to examine the extent of pro-inflammatory M1 microglial polarization. Fluoro-Gold labelling was then utilized to identify viable ganglion cells, while H&E staining was used to examine retinal morphology post-I/R and exosome treatment. RESULTS: Sca-1+ exosome-injected mice yielded better visual functional preservation and lowered inflammatory factors, compared to Sca-1-, at days 1, 3, and 7 days post-I/R. miRNA sequencing found that Sca-1+ exosomes had higher miR-150-5p levels, compared to Sca-1- exosomes, which was confirmed by RT-qPCR. Mechanistic analysis found that miR-150-5p from Sca-1+ exosomes repressed the mitogen-activated protein kinase kinase kinase 3 (MEKK3)/JNK/c-Jun axis, leading to IL-6 and TNF-α downregulation, and subsequently reduced microglial polarization, all of which contributes to reduced ganglion cell apoptosis and preservation of proper retinal morphology. CONCLUSION: This study elucidates a potential new therapeutic approach for neuroprotection against I/R injury, via delivering miR-150-5p-enriched Sca-1+ exosomes, which targets the miR-150-5p/MEKK3/JNK/c-Jun axis, thereby serving as a cell-free remedy for treating retinal I/R injury and preserving visual functioning.


Asunto(s)
Exosomas , MicroARNs , Daño por Reperfusión , Ratones , Animales , Microglía/metabolismo , MicroARNs/metabolismo , Exosomas/metabolismo , Daño por Reperfusión/metabolismo , Células de la Médula Ósea/metabolismo
8.
Zhongguo Zhong Yao Za Zhi ; 48(11): 2876-2895, 2023 Jun.
Artículo en Zh | MEDLINE | ID: mdl-37381950

RESUMEN

Microbial transformation is an efficient enzymatic approach for the structural modification of exogenous compounds to obtain derivatives. Compared with traditional chemical synthesis, the microbial transformation has in fact the undoubtable advantages of strong region-and stereo-selectivity, and a low environmental and economic impact on the production process, which can achieve the reactions challenging to chemical synthesis. Because microbes are equipped with a broad-spectrum of enzymes and therefore can metabolize various substrates, they are not only a significant route for obtaining novel active derivatives, but also an effective tool for mimicking mammal metabolism in vitro. Artemisinin, a sesquiterpene with a peroxy-bridged structure serving as the main active functional group, is a famous antimalarial agent discovered from Artemisia annua L. Some sesquiterpenoids, such as dihydroartemisinin, artemether, and arteether, have been developed on the basis of artemisinin, which have been successfully marketed and become the first-line antimalarial drugs recommended by WHO. As revealed by pharmacological studies, artemisinin and its derivatives have exhibited extensive biological activities, including antimalarial, antitumor, antiviral, anti-inflammatory, and immunomodulatory. As an efficient approach for structural modification, microbial transformation of artemisinin and its derivatives is an increasingly popular strategy that attracts considerable attention recently, and numerous novel derivatives have been discovered. Herein, this paper reviewed the microbial transformation of artemisinin and its artemisinin, including microbial strains, culture conditions, product isolation and yield, and biological activities, and summarized the advances in microbial transformation in obtaining active derivatives of artemisinin and the simulation of in vivo metabolism of drugs.


Asunto(s)
Antimaláricos , Artemisininas , Animales , Antimaláricos/farmacología , Antivirales , Arteméter , Mamíferos
9.
Zhongguo Dang Dai Er Ke Za Zhi ; 25(6): 595-599, 2023 Jun 15.
Artículo en Zh | MEDLINE | ID: mdl-37382128

RESUMEN

OBJECTIVES: To study the clinical features of children with febrile seizures after Omicron variant infection. METHODS: A retrospective analysis was performed on the clinical data of children with febrile seizures after Omicron variant infection who were admitted to the Department of Neurology, Children's Hospital Affiliated to the Capital Institute of Pediatrics, from December 1 to 31, 2022 (during the epidemic of Omicron variant; Omicron group), and the children with febrile seizures (without Omicron variant infection) who were admitted from December 1 to 31, in 2021 were included as the non-Omicron group. Clinical features were compared between the two groups. RESULTS: There were 381 children in the Omicron group (250 boys and 131 girls), with a mean age of (3.2±2.4) years. There were 112 children in the non-Omicron group (72 boys and 40 girls), with a mean age of (3.5±1.8) years. The number of children in the Omicron group was 3.4 times that in the non-Omicron group. The proportion of children in two age groups, aged 1 to <2 years and 6-10.83 years, in the Omicron group was higher than that in the non-Omicron group, while the proportion of children in two age groups, aged 4 to <5 years and 5 to <6 years, was lower in the Omicron group than that in the non-Omicron group (P<0.05).The Omicron group had a significantly higher proportion of children with cluster seizures and status convulsion than the non-Omicron group (P<0.05). Among the children with recurrence of febrile seizures, the proportion of children aged 6-10.83 years in the Omicron group was higher than that in the non-Omicron group, while the proportion of children aged 3 years, 4 years, and 5 years in the Omicron group was lower than that in the non-Omicron group (P<0.05). CONCLUSIONS: Children with febrile seizures after Omicron variant infection tend to have a wider age range, with an increase in the proportion of children with cluster seizures and status convulsion during the course of fever.


Asunto(s)
Epidemias , Epilepsia Generalizada , Convulsiones Febriles , Masculino , Femenino , Humanos , Niño , Lactante , Preescolar , Convulsiones Febriles/etiología , Estudios Retrospectivos , Convulsiones , Fiebre
10.
Nano Lett ; 21(15): 6678-6683, 2021 Aug 11.
Artículo en Inglés | MEDLINE | ID: mdl-34296602

RESUMEN

We describe how the out-of-plane dielectric polarizability of monolayer graphene influences the electrostatics of bilayer graphene-both Bernal (BLG) and twisted (tBLG). We compare the polarizability value computed using density functional theory with the output from previously published experimental data on the electrostatically controlled interlayer asymmetry potential in BLG and data on the on-layer density distribution in tBLG. We show that monolayers in tBLG are described well by polarizability αexp = 10.8 Å3 and effective out-of-plane dielectric susceptibility ϵz = 2.5, including their on-layer electron density distribution at zero magnetic field and the interlayer Landau level pinning at quantizing magnetic fields.

11.
J Am Chem Soc ; 143(49): 20811-20817, 2021 12 15.
Artículo en Inglés | MEDLINE | ID: mdl-34846141

RESUMEN

The aim of molecular electronics is to miniaturize active electronic devices and ultimately construct single-molecule nanocircuits using molecules with diverse structures featuring various functions, which is extremely challenging. Here, we realize a gate-controlled rectifying function (the on/off ratio reaches ∼60) and a high-performance field effect (maximum on/off ratio >100) simultaneously in an initially symmetric single-molecule photoswitch comprising a dinuclear ruthenium-diarylethene (Ru-DAE) complex sandwiched covalently between graphene electrodes. Both experimental and theoretical results consistently demonstrate that the initially degenerated frontier molecular orbitals localized at each Ru fragment in the open-ring Ru-DAE molecule can be tuned separately and shift asymmetrically under gate electric fields. This symmetric orbital shifting (AOS) lifts the degeneracy and breaks the molecular symmetry, which is not only essential to achieve a diode-like behavior with tunable rectification ratio and controlled polarity, but also enhances the field-effect on/off ratio at the rectification direction. In addition, this gate-controlled symmetry-breaking effect can be switched on/off by isomerizing the DAE unit between its open-ring and closed-ring forms with light stimulus. This new scheme offers a general and efficient strategy to build high-performance multifunctional molecular nanocircuits.

12.
Acta Pharmacol Sin ; 42(8): 1347-1353, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33116249

RESUMEN

To discover effective drugs for COVID-19 treatment amongst already clinically approved drugs, we developed a high throughput screening assay for SARS-CoV-2 virus entry inhibitors using SARS2-S pseudotyped virus. An approved drug library of 1800 small molecular drugs was screened for SARS2 entry inhibitors and 15 active drugs were identified as specific SARS2-S pseudovirus entry inhibitors. Antiviral tests using native SARS-CoV-2 virus in Vero E6 cells confirmed that 7 of these drugs (clemastine, amiodarone, trimeprazine, bosutinib, toremifene, flupenthixol, and azelastine) significantly inhibited SARS2 replication, reducing supernatant viral RNA load with a promising level of activity. Three of the drugs were classified as histamine receptor antagonists with clemastine showing the strongest anti-SARS2 activity (EC50 = 0.95 ± 0.83 µM). Our work suggests that these 7 drugs could enter into further in vivo studies and clinical investigations for COVID-19 treatment.


Asunto(s)
Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Reposicionamiento de Medicamentos , SARS-CoV-2/efectos de los fármacos , Internalización del Virus/efectos de los fármacos , Línea Celular , Aprobación de Drogas , Ensayos Analíticos de Alto Rendimiento , Humanos , Pruebas de Sensibilidad Microbiana , SARS-CoV-2/fisiología , Glicoproteína de la Espiga del Coronavirus/efectos de los fármacos
13.
Angew Chem Int Ed Engl ; 60(22): 12274-12278, 2021 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-33650169

RESUMEN

Charge transport in a single-molecule junction is extraordinarily sensitive to both the internal electronic structure of a molecule and its microscopic environment. Two distinct conductance states of a prototype terphenyl molecule are observed, which correspond to the bistability of outer phenyl rings at each end. An azobenzene unit is intentionally introduced through atomically precise side-functionalization at the central ring of the terphenyl, which is reversibly isomerized between trans and cis forms by either electric or optical stimuli. Both experiment and theory demonstrate that the azobenzene side-group delicately modulates charge transport in the backbone via a single-molecule stereoelectronic effect. We reveal that the dihedral angle between the central and outer phenyl ring, as well as the corresponding rotation barrier, is subtly controlled by isomerization, while the behaviors of the phenyl ring away from the azobenzene are hardly affected. This tunability offers a new route to precisely engineer multiconfigurational single-molecule memories, switches, and sensors.

14.
Acta Pharmacol Sin ; 41(9): 1133-1140, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32555446

RESUMEN

Since the outbreak of novel coronavirus pneumonia (COVID-19) in December 2019, more than 2,500,000 people worldwide have been diagnosed with SARS-CoV-2 as of April 22. In response to this epidemic, China has issued seven trial versions of diagnosis and treatment protocol for COVID-19. According to the information that we have collected so far, this article provides an overview of potential therapeutic drugs and compounds with much attention, including favipiravir and hydroxychloroquine, as well as traditional Chinese medicine, which have been reported with good clinical treatment effects. Moreover, with further understanding of SARS-CoV-2 virus, new drugs targeting specific SARS-CoV-2 viral components arise and investigations on these novel anti-SARS-CoV-2 agents are also reviewed.


Asunto(s)
Antivirales/farmacología , Betacoronavirus/efectos de los fármacos , Infecciones por Coronavirus , Medicina Tradicional China/métodos , Pandemias , Neumonía Viral , Betacoronavirus/fisiología , COVID-19 , Protocolos Clínicos , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/fisiopatología , Humanos , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/etiología , Neumonía Viral/fisiopatología , SARS-CoV-2
15.
Zhongguo Zhong Yao Za Zhi ; 45(18): 4416-4422, 2020 Sep.
Artículo en Zh | MEDLINE | ID: mdl-33164371

RESUMEN

Twenty-six batches of Gardeniae Fructus from different producing area were collected for the development of the fingerprint, and the main components of Gardeniae Fructus were identified by liquid chromatography-mass spectrometry. The producing areas of Gardeniae Fructus were distinguished by chemical pattern recognition technology, and the index components of Gardeniae Fructus were quantitated. An UPLC wavelength switching method was adopted, and the separation was carried out on a Waters Acquity UPLC HASS C_(18)(2.1 mm×100 mm, 1.7 µm) column using the mobile phase of acetonitrile-0.5% formic acid water for gradient elution. Principal component analysis(PCA) and orthogonal partial least square discriminant analysis(OPLS-DA) were used for the data ana-lysis. The results showed that the similarity of 26 batches of Gardeniae Fructus was more than 0.89, and ten common peaks were defined. Sixteen compounds including monoterpenes, iridoids and diterpenoids were identified by reference identification, literature comparison and high-resolution mass spectrometry data analysis. The distinguishment of origin of Gardeniae Fructus was realized by PCA and OPLS-DA analysis, and two quality differential markers were screened as geniposide and crocin Ⅰ. The contents of crocin Ⅰ, crocin Ⅱ and geniposide in Gardeniae Fructus from different places were different. These results will provide reference for the geographical origin traceability of Gardeniae Fructus.


Asunto(s)
Medicamentos Herbarios Chinos , Gardenia , Cromatografía Líquida de Alta Presión , Frutas , Control de Calidad
16.
Virol J ; 16(1): 166, 2019 12 30.
Artículo en Inglés | MEDLINE | ID: mdl-31888694

RESUMEN

BACKGROUND: Enterovirus 71 (EV71) and coxsackievirus A16 (CA16) are the two main etiological agents of Hand, Foot and Mouth Disease (HFMD). Simple and rapid detection of EV71 and CA16 is critical in resource-limited settings. METHODS: Duplex real time reverse-transcription recombinase aided amplification (RT-RAA) assays incorporating competitive internal amplification controls (IAC) and visible RT-RAA assays combined with lateral flow strip (LFS) for detection of EV71 and CA16 were developed respectively. Duplex real time RT-RAA assays were performed at 42 °C within 30 min using a portable real-time fluorescence detector, while LFS RT-RAA assays were performed at 42 °C within 30 min in an incubator. Recombinant plasmids containing conserved VP1 genes were used to analyze the sensitivities of these two methods. A total of 445 clinical specimens from patients who were suspected of being infected with HFMD were used to evaluate the performance of the assays. RESULTS: The limit of detection (LoD) of the duplex real time RT-RAA for EV71 and CA16 was 47 copies and 38 copies per reaction, respectively. The LoD of the LFS RT-RAA for EV71 and CA16 were both 91 copies per reaction. There was no cross reactivity with other enteroviruses. Compared to reverse transcription-quantitative PCR (RT-qPCR), the clinical diagnostic sensitivities of the duplex real time RT-RAA assay were 92.3% for EV71 and 99.0% for CA16, and the clinical diagnostic specificities were 99.7 and 100%, respectively. The clinical diagnostic sensitivities of the LFS RT-RAA assay were 90.1% for EV71 and 94.9% for CA16, and the clinical diagnostic specificities were 99.7 and 100%, respectively. CONCLUSIONS: The developed duplex real time RT-RAA and LFS RT-RAA assays for detection of EV71 and CA16 are potentially suitable in primary clinical settings.


Asunto(s)
Enterovirus Humano A/aislamiento & purificación , Enterovirus/aislamiento & purificación , Enfermedad de Boca, Mano y Pie/diagnóstico , Técnicas de Diagnóstico Molecular/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Enterovirus/genética , Enterovirus Humano A/genética , Humanos , Sensibilidad y Especificidad
17.
Virol J ; 16(1): 86, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31262315

RESUMEN

BACKGROUND: Human adenoviruses are a common group of viruses that cause acute infectious diseases. Human adenovirus (HAdV) 3 and HAdV 7 cause major outbreaks of severe pneumonia. A reliable and practical method for HAdV typing in clinical laboratories is lacking. A simple, rapid and accurate molecular typing method for HAdV may facilitate clinical diagnosis and epidemiological control. METHODS: We developed and evaluated duplex real-time recombinase-aided amplification (RAA) assays incorporating competitive internal controls for detection of HAdV 3 and HAdV 7, respectively. The assays were performed in a one-step in a single tube reaction at 39° for 20 min. RESULTS: The analytical sensitivities of the duplex RAA assays for HAdV 3 and HAdV 7 were 5.0 and 14.8 copies per reaction, respectively (at 95% probability by probit regression analysis). No cross-reaction was observed with other types of HAdV or other common respiratory viruses. The duplex RAA assays were used to detect 152 previously-defined HAdV-positive samples. These results agreed with those obtained using a published triplex quantitative real-time PCR protocol. CONCLUSIONS: We provide the first report of internally-controlled duplex RAA assays for the detection of HAdV 3 and HAdV 7. These assays effectively reduce the rate of false negative results and may be valuable for detection of HAdV 3 and HAdV 7 in clinical laboratories, especially in resource-poor settings.


Asunto(s)
Adenovirus Humanos/aislamiento & purificación , Técnicas de Amplificación de Ácido Nucleico/métodos , Técnicas de Amplificación de Ácido Nucleico/normas , Recombinasas/genética , Adenovirus Humanos/genética , Humanos , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Reacción en Cadena en Tiempo Real de la Polimerasa/normas , Infecciones del Sistema Respiratorio/epidemiología , Sensibilidad y Especificidad , Serogrupo , Temperatura
18.
J Cell Mol Med ; 22(1): 131-140, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28816021

RESUMEN

CD155, one of the nectin-like molecule family members, is involved in cell adhesion and motility. CD155 is overexpressed in several human cancers, but its role in proliferation and apoptosis of colorectal cancer remains unclear. We found that CD155 was up-regulated in colorectal cancer tissues. CD155 knockdown via shRNA lentiviruses inhibited colon cancers cell migration and invasion, with a reduction in the expression of FAK, Src and MMP-2. CD155 down-regulation also suppressed colon cancer cell proliferation, accompanied by changing expressions of some molecules related to cell cycle. Finally, CD155 knockdown increased the expression ratio between Bax and Bcl-2, resulting in a significant increase in colon cancer cell apoptosis. Taken together, these results demonstrate that CD155 is involved in not only migration and invasion but also proliferation and survival abilities of colon cancer cells, suggesting that CD155 is one of key molecules promoting the growth and metastasis of colorectal cancer.


Asunto(s)
Apoptosis , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Técnicas de Silenciamiento del Gen , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptores Virales/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Adulto , Animales , Carcinogénesis/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Femenino , Silenciador del Gen , Humanos , Masculino , Ratones Endogámicos BALB C , Persona de Mediana Edad , Invasividad Neoplásica , Regulación hacia Arriba/genética , Ensayos Antitumor por Modelo de Xenoinjerto
19.
J Biol Chem ; 292(49): 20270-20280, 2017 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-29042442

RESUMEN

1α,25-Dihydroxyvitamin D3 (1,25(OH)2D3) is the active form of vitamin D, which is responsible for reducing the risk for diabetes mellitus (DM), decreasing insulin resistance, and improving insulin secretion. Previous studies have shown that 1,25(OH)2D3 inhibited the activity of FoxO1, which has been implicated in the regulation of glucose metabolism. However, its function and mechanism of action in DM-induced energy disorders and also in bone development remains unclear. Here, using in vitro and in vivo approaches including osteoblast-specific, conditional FoxO1-knock-out mice, we demonstrate that 1,25(OH)2D3 ameliorates abnormal osteoblast proliferation in DM-induced oxidative stress conditions and rescues the impaired glucose and bone metabolism through FoxO1 nuclear exclusion resulting from the activation of PI3K/Akt signaling. Using alizarin red staining, alkaline phosphatase assay, Western blot, and real-time qPCR techniques, we found that 1,25(OH)2D3 promotes osteoblast differentiation and expression of osteogenic phenotypic markers (i.e. alkaline phosphatase (1), collagen 1 (COL-1), osteocalcin (OCN), and osteopontin (OPN)) in a high-glucose environment. Moreover, 1,25(OH)2D3 increased both total OCN secretion and levels of uncarboxylated OCN (GluOC) by phosphorylating FoxO1 and promoting its nuclear exclusion, indicated by Western blot and cell immunofluorescence analyses. Taken together, our findings confirm that FoxO1 is a key mediator involved in glucose homeostasis and indicate that 1,25(OH)2D3 improves glucose metabolism and bone development via regulation of PI3K/Akt/FoxO1/OCN pathway.


Asunto(s)
Proteína Forkhead Box O1/metabolismo , Osteogénesis/efectos de los fármacos , Vitamina D/análogos & derivados , Animales , Núcleo Celular/química , Proliferación Celular , Glucosa/metabolismo , Homeostasis/efectos de los fármacos , Ratones , Ratones Endogámicos NOD , Osteoblastos/metabolismo , Osteocalcina/efectos de los fármacos , Osteocalcina/metabolismo , Estrés Oxidativo , Fosforilación , Vitamina D/farmacología
20.
Cell Physiol Biochem ; 51(6): 2523-2535, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30562752

RESUMEN

BACKGROUND/AIMS: Inflammation plays a vital role in the etiology and pathogenesis of chronic noncommunicable diseases (NCDs), which are the leading health issues throughout the world. Our previous studies verified the satisfactory therapeutic effects of Coccomyxa gloeobotrydiformis (CGD) polysaccharide on several NCDs. In this study, we aimed to investigate the anti-inflammatory effects of CGD polysaccharide, and the corresponding molecular mechanisms, on lipopolysaccharide (LPS)-induced inflammation in RAW264.7 cells. METHODS: A viability assay and a lactate dehydrogenase (LDH) assay were used to measure the cytotoxic effects of CGD polysaccharide on LPS-stimulated RAW264.7 cells. To investigate the potential anti-inflammatory mechanisms of CGD polysaccharide in LPS-stimulated RAW264.7 cells, nitric oxide (NO) production was determined using a NO assay and the expression of inflammatory mediators (PGE2, iNOS and COX-2), inflammatory cytokines (TNF-α, IL-6, IL-1ß and IL-10) and inflammation-related signaling pathways (the MAPK/NF-κB, PI3K/AKT/JNK, JAK/STAT and Nrf2/HO-1pathways) were observed by western blotting. The translocation of NF-κB p65 was also observed using an immunofluorescent assay. RESULTS: CGD polysaccharide significantly inhibited LPS-induced NO production and PGE2 expression by reducing the expression of iNOS and COX-2. It also suppressed the expression of the pro-inflammatory cytokines TNF-α, IL-6 and IL-1ß, and up-regulated the expression of the anti-inflammatory cytokine IL-10. Further experiments demonstrated that CGD polysaccharide could inhibit inflammatory signaling pathways (the MAPK/NF-κB, PI3K/AKT/JNK and JAK/STAT pathways). At the same time, it enhanced the anti-inflammatory pathway Nrf2/HO-1. In addition, CGD polysaccharide did not display any cytotoxic effects, even at a high concentration. CONCLUSION: Taken together, the results suggest that CGD polysaccharide significantly inhibits LPS-induced inflammation in RAW264.7 cells. This effect lies in its regulatory effects on the signaling pathways MAPK/ NF-κB, PI3K/AKT/JNK, JAK/STAT and Nrf2/HO-1.Our findings reveal that CGD polysaccharide has the potential to be used as a relatively safe and effective drug as part of the treatment of NCDs.


Asunto(s)
Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Lipopolisacáridos/inmunología , Macrófagos/efectos de los fármacos , Polisacáridos/farmacología , Animales , Antiinflamatorios/química , Ciclooxigenasa 2/inmunología , Citocinas/inmunología , Dinoprostona/inmunología , Inflamación/inmunología , Macrófagos/inmunología , Ratones , Microalgas/química , Óxido Nítrico/inmunología , Óxido Nítrico Sintasa de Tipo II/inmunología , Polisacáridos/química , Células RAW 264.7
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