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1.
Virol Sin ; 39(3): 369-377, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38599520

RESUMEN

Infectious diseases caused by arboviruses are a public health concern in Pakistan. However, studies on data prevalence and threats posed by arboviruses are limited. This study investigated the seroprevalence of arboviruses in a healthy population in Pakistan, including severe fever with thrombocytopenia syndrome virus (SFTSV), Crimean-Congo hemorrhagic fever virus (CCHFV), Tamdy virus (TAMV), and Karshi virus (KSIV) based on a newly established luciferase immunoprecipitation system (LIPS) assays, and Zika virus (ZIKV) by enzyme-linked immunosorbent assays (ELISA). Neutralizing activities against these arboviruses were further examined from the antibody positive samples. The results showed that the seroprevalence of SFTSV, CCHFV, TAMV, KSIV, and ZIKV was 17.37%, 7.58%, 4.41%, 1.10%, and 6.48%, respectively, and neutralizing to SFTSV (1.79%), CCHFV (2.62%), and ZIKV (0.69%) were identified, as well as to the SFTSV-related Guertu virus (GTV, 0.83%). Risk factors associated with the incidence of exposure and levels of antibody response were analyzed. Moreover, co-exposure to different arboviruses was demonstrated, as thirty-seven individuals were having antibodies against multiple viruses and thirteen showed neutralizing activity. Males, individuals aged ≤40 years, and outdoor workers had a high risk of exposure to arboviruses. All these results reveal the substantial risks of infection with arboviruses in Pakistan, and indicate the threat from co-exposure to multiple arboviruses. The findings raise the need for further epidemiologic investigation in expanded regions and populations and the necessity to improve health surveillance in Pakistan.


Asunto(s)
Anticuerpos Neutralizantes , Anticuerpos Antivirales , Infecciones por Arbovirus , Arbovirus , Humanos , Pakistán/epidemiología , Estudios Seroepidemiológicos , Masculino , Femenino , Adulto , Infecciones por Arbovirus/epidemiología , Infecciones por Arbovirus/virología , Anticuerpos Antivirales/sangre , Adulto Joven , Persona de Mediana Edad , Arbovirus/inmunología , Arbovirus/aislamiento & purificación , Adolescente , Niño , Anticuerpos Neutralizantes/sangre , Factores de Riesgo , Anciano , Preescolar , Ensayo de Inmunoadsorción Enzimática
2.
Virol Sin ; 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38679334

RESUMEN

Ticks are a major parasite on the Qinghǎi-Tibet Plateau, western China, and represent an economic burden to agriculture and animal husbandry. Despite research on tick-borne pathogens that threaten humans and animals, the viromes of dominant tick species in this area remain unknown. In this study, we collected Dermacentor nuttalli ticks near Qinghǎi Lake and identified 13 viruses belonging to at least six families through metagenomic sequencing. Four viruses were of high abundance in pools, including Xinjiang tick-associated virus 1 (XJTAV1), and three novel viruses: Qinghǎi Lake virus 1, Qinghǎi Lake virus 2 (QHLV1, and QHLV2, unclassified), and Qinghǎi Lake virus 3 (QHLV3, genus Uukuvirus of family Phenuiviridae in order Bunyavirales), which lacks the M segment. The minimum infection rates of the four viruses in the tick groups were 8.2%, 49.5%, 6.2%, and 24.7%, respectively, suggesting the prevalence of these viruses in D. nuttalli ticks. A putative M segment of QHLV3 was identified from the next-generation sequencing data and further characterized for its signal peptide cleavage site, N-glycosylation, and transmembrane region. Furthermore, we probed the L, M, and S segments of other viruses from sequencing data of other tick pools by â€‹using the putative M segment sequence of QHLV3. By revealing the viromes of D. nuttalli ticks, this study enhances our understanding of tick-borne viral communities in highland regions. The putative M segment identified in a novel uukuvirus suggests that previously identified uukuviruses without M segments should have had the same genome organization as typical bunyaviruses. These findings will facilitate virus discovery and our understanding of the phylogeny of tick-borne uukuviruses.

3.
Nat Commun ; 15(1): 709, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38267417

RESUMEN

Anisotropic materials with oppositely signed dielectric tensors support hyperbolic polaritons, displaying enhanced electromagnetic localization and directional energy flow. However, the most reported hyperbolic phonon polaritons are difficult to apply for active electro-optical modulations and optoelectronic devices. Here, we report a dynamic topological plasmonic dispersion transition in black phosphorus via photo-induced carrier injection, i.e., transforming the iso-frequency contour from a pristine ellipsoid to a non-equilibrium hyperboloid. Our work also demonstrates the peculiar transient plasmonic properties of the studied layered semiconductor, such as the ultrafast transition, low propagation losses, efficient optical emission from the black phosphorus's edges, and the characterization of different transient plasmon modes. Our results may be relevant for the development of future optoelectronic applications.

4.
Infect Dis (Lond) ; 56(1): 59-65, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37850325

RESUMEN

BACKGROUND: Tick-borne viral diseases have become an increasingly important public health concern. Tamdy virus (TAMV) is a tick-borne virus of the genus Orthonairovirus in the family Nairoviridae. While some studies have suggested that TAMV is a pathogen associated with human febrile illness, its epidemiology and the risk of TAMV spill-over remain poorly understood. METHODS: Ticks were collected in Xinjiang, China, and grouped into pools. RT-PCR assays were used to detect TAMV RNA in these pools. The seroprevalence of TAMV was investigated using Immunofluorescence assays, Western blotting, and Luciferase immunoprecipitation system (LIPS) assays. RESULTS: TAMV RNA was detected in 17 out of 363 tick pools, resulting in a minimum infection rate (MIR) of 4.7%. Hyalomma asiaticum and Dermacentor nuttalli were identified as major tick vectors of TAMV. Phylogenetic analysis demonstrated that TAMV strains from Xinjiang are closely related to strains from other countries. Seroprevalence studies showed that TAMV exposure has been occurring in Xinjiang since at least 2006. Antibody responses to TAMV were detected in 1.1% (26/2296) of animals, including domestic animals and wild rodents. The seropositivity rates were as follows: sheep (1.7%), dog (2.3%), Marmota monax (0.8%), Meriones meridianus (3.5%). CONCLUSIONS: The research findings reveal that TAMV can be transmitted by ticks to various animal species, posing a significant public health risk. The wide distribution of TAMV and its tick vectors emphasise the importance of early preparedness and control measures. This study highlights the necessity for maintaining vigilance in addressing emerging zoonotic diseases transmitted by ticks.


Asunto(s)
Enfermedades por Picaduras de Garrapatas , Garrapatas , Animales , Humanos , Perros , Ovinos , Filogenia , Estudios Seroepidemiológicos , Zoonosis/epidemiología , Enfermedades por Picaduras de Garrapatas/epidemiología , ARN
5.
Nanoscale ; 15(21): 9297-9303, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37161768

RESUMEN

The number of excellent 2D materials is finite for nano optoelectric devices including transistors, diodes, sensors, and so forth, thus the modulation of 2D materials is important to improve the performance of the current eligible 2D materials, and even to transform unqualified 2D materials into eligible 2D materials. Here we develop a fine laser doping strategy based on highly controllable laser direct writing, and investigate its effectivity and practicability by doping multilayer molybdenum ditelluride (MoTe2). Power-gradient laser doping and patterned laser doping, for the first time, are presented for designable and fine doping of 2D materials. The laser-induced polar transition of MoTe2 indicates good controllability of the method for the carrier concentration distribution in MoTe2. Multiple devices with finely tuned energy band structures are demonstrated by means of power-gradient laser doping and patterned laser doping, further illustrating the design capability of a precise energy band in 2D materials.

6.
Medicine (Baltimore) ; 101(42): e31266, 2022 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-36281139

RESUMEN

Diabetic macular edema (DME) is the complication of diabetic retinopathy, the leading cause of vision loss among diabetic patients. Metformin is the main antidiabetic treatment. It is preferable for its great anti-angiogenic and anti-inflammatory effects. Anti-vascular endothelial growth factor (VEGF) therapy is the preferable treatment for DME despite its lack of convincing results in some patients. To assess whether the combination of metformin and anti-VEGF drugs may decrease the risk of anti-VEGF resistance among DME patients. We included DME patients with a central retinal thickness (CRT) ≥ 250 µm who consecutively underwent at least 3 anti-VEGF therapies from January 1, 2020, to December 30, 2021. Anti-VEGF resistance was defined as persistent macular edema with decreased CRT ≤ 25% after 3 anti-VEGF injections. 109 patients were considered for this research, of whom 65 (59.6%) were resistant to anti-VEGF therapy. The mean CRT of the non-metformin group decreased from 344.88 ± 129.48 to 318.29 ± 123.23 (20.85%) and from 415.64 ± 144.26 to 277.11 ± 99.25 (31.51%) (P = .031) in the metformin group. Moreover, the metformin group had fewer resistant patients than the non-metformin, 24 (45.3%) versus 41 (73.2%). Furthermore, a considerable gain in visual acuity was observed in both groups, with a BCVA gain of 40.41% in the metformin group and 39.9% in the non-metformin group. Metformin may be combined with an anti-VEGF drug to minimize the risk of anti-VEGF resistance among DME patients. Moreover, it can serve to design effective therapeutic deliveries.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Edema Macular , Metformina , Humanos , Antiinflamatorios/uso terapéutico , Diabetes Mellitus/tratamiento farmacológico , Retinopatía Diabética/complicaciones , Hipoglucemiantes/uso terapéutico , Edema Macular/tratamiento farmacológico , Edema Macular/etiología , Metformina/uso terapéutico , Ranibizumab/uso terapéutico , Factor A de Crecimiento Endotelial Vascular
8.
Virol Sin ; 37(1): 107-114, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35234635

RESUMEN

Severe fever with thrombocytopenia syndrome (SFTS), caused by SFTS virus (SFTSV) infection, was first reported in 2010 in China with an initial fatality of up to 30%. The laboratory confirmation of SFTSV infection in terms of detection of viral RNA or antibody levels is critical for SFTS diagnosis and therapy. In this study, a new luciferase immunoprecipitation system (LIPS) assay based on pREN2 plasmid expressing SFTSV NP gene and tagged with Renilla luciferase (Rluc), was established and used to investigate the levels of antibody responses to SFTSV. Totally 464 serum samples from febrile patients were collected in the hospital of Shaoxing City in Zhejiang Province in 2019. The results showed that 82 of the 464 patients (17.7%) had antibody response to SFTSV, which were further supported by immunofluorescence assays (IFAs). Further, qRT-PCR and microneutralization tests showed that among the 82 positive cases, 15 patients had viremia, 10 patients had neutralizing antibody, and one had both (totally 26 patient). However, none of these patients were diagnosed as SFTS in the hospital probably because of their mild symptoms or subclinical manifestations. All the results indicated that at least the 26 patients having viremia or neutralizing antibody were the missed diagnosis of SFTS cases. The findings suggested the occurrence of SFTS and the SFTS incidence were higher than the reported level in Shaoxing in 2019, and that LIPS may provide an alternative strategy to confirm SFTSV infection in the laboratory.


Asunto(s)
Infecciones por Bunyaviridae , Phlebovirus , Síndrome de Trombocitopenia Febril Grave , Anticuerpos Antivirales , China/epidemiología , Humanos , Inmunoprecipitación , Luciferasas/genética , Diagnóstico Erróneo , Phlebovirus/genética , Síndrome de Trombocitopenia Febril Grave/diagnóstico
9.
Natl Sci Rev ; 9(12): nwac020, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36694799

RESUMEN

The second-order nonlinear Hall effect observed in the time-reversal symmetric system has not only shown abundant physical content, but also exhibited potential application prospects. Recently, a third-order nonlinear Hall effect has been observed in MoTe2 and WTe2. However, few-layer MoTe2 and WTe2 are usually unstable in air and the observed third-order nonlinear Hall effect can be measured only at low temperature, which hinders further investigation as well as potential application. Thus, exploring new air-stable material systems with a sizable third-order nonlinear Hall effect at room temperature is an urgent task. Here, in type-II Weyl semimetal TaIrTe4, we observed a pronounced third-order nonlinear Hall effect, which can exist at room temperature and remain stable for months. The third-order nonlinear Hall effect is connected to the Berry-connection polarizability tensor instead of the Berry curvature. The possible mechanism of the observation of the third-order nonlinear Hall effect in TaIrTe4 at room temperature has been discussed. Our findings will open an avenue towards exploring room-temperature nonlinear devices in new quantum materials.

10.
Nanotechnology ; 32(50)2021 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-34530404

RESUMEN

Achieving a large enhancement of local electromagnetic fields in the ultraviolet waveband is desirable for some applications such as surface-enhanced Raman scattering and surface-enhanced fluorescence. In addition, it is more significant for some applications such as plasmon-enhanced harmonic generation to enhance the intensity of local electromagnetic fields and increase their decay time at the same time. In this paper, using the finite-difference time-domain method, we numerically demonstrate that using the linearly polarized light with a wavelength of 325 nm as the illumination light, an isolated triangular Al-SiO2-Al hybrid nanoplate with optimized geometric parameters can produce a local electric field enhanced by a factor of about 108 at one of its top apexes, and produce two local electric fields enhanced by a factor of about 150 at two transverse dielectric/metal interfaces of one of its longitudinal side edges. Moreover, we also numerically demonstrate that the decay time of enhanced local electric fields produced by the isolated triangular Al-SiO2-Al hybrid nanoplate is about 1.6 times as large as that of enhanced local electric fields produced by an isolated triangular Al nanoplate. These unique properties of the isolated triangular Al-SiO2-Al hybrid nanoplate arise because of both the transverse coupling and the longitudinal coupling of localized surface plasmon polaritons in this structure. Our findings make triangular Al-SiO2-Al hybrid nanoplates very promising for application in many fields such as surface-enhanced Raman scattering and plasmon-enhanced harmonic generation.

11.
RSC Adv ; 10(55): 33544-33548, 2020 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-35515068

RESUMEN

Atomic-thin MoS2 materials have attracted increasing attention due to their potentials in numerous fields. However, in 2D-MoS2 sheets, the edge region usually has unique features differing from the interior region, which has potential application in enhancing catalysts and shape-dependent 2D-nanodevices. However, fabricating it cost-effectively is still very difficult. Here, we present one universal method to obtain various shape-dependent closed-edge 2D-MoS2 nanobelts only using one simple step, and width of the MoS2 nanobelts (minimum of 270 nm) were adjustable. Our strategy opens a new fabrication route for closed-edge 2D-MoS2 nanobelts, and in principle, this method is also suitable for other CVD-grown 2D materials.

12.
Cell Rep ; 21(10): 2671-2677, 2017 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-29212015

RESUMEN

Although the intrinsic mechanisms that control whether stem cells divide symmetrically or asymmetrically underlie tissue growth and homeostasis, they remain poorly defined. We report that the RNA-binding protein fragile X mental retardation protein (FMRP) limits the symmetric division, and resulting expansion, of the stem cell population during adaptive intestinal growth in Drosophila. The elevated insulin sensitivity that FMRP-deficient progenitor cells display contributes to their accelerated expansion, which is suppressed by the depletion of insulin-signaling components. This FMRP activity is mediated solely via a second conserved RNA-binding protein, LIN-28, known to boost insulin signaling in stem cells. Via LIN-28, FMRP controls progenitor cell behavior by post-transcriptionally repressing the level of insulin receptor (InR). This study identifies the stem cell-based mechanism by which FMRP controls tissue adaptation, and it raises the possibility that defective adaptive growth underlies the accelerated growth, gastrointestinal, and other symptoms that affect fragile X syndrome patients.


Asunto(s)
Proteínas de Drosophila/metabolismo , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/metabolismo , Intestinos/citología , Proteínas de Unión al ARN/metabolismo , Células Madre/citología , Células Madre/metabolismo , Animales , Proteínas de Drosophila/genética , Femenino , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Proteínas de Unión al ARN/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo
13.
Mol Biol Cell ; 27(19): 2911-23, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27489338

RESUMEN

Polyploid cancer cells exhibit chromosomal instability (CIN), which is associated with tumorigenesis and therapy resistance. The mechanisms that induce polyploidy and how these mechanisms contribute to CIN are not fully understood. Here we evaluate CIN in human cells that become polyploid through an experimentally induced endoreplication cycle. When these induced endoreplicating cells (iECs) returned to mitosis, it resulted in aneuploidy in daughter cells. This aneuploidy resulted from multipolar divisions, chromosome missegregation, and failure in cytokinesis. The iECs went through several rounds of division, ultimately spawning proliferative cells of reduced ploidy. iECs have reduced levels of the kinesin-14 HSET, which likely accounts for the multipolar divisions, and overexpression of HSET reduced spindle multipolarity. However, HSET overexpression had only mild effects on CIN, suggesting that additional defects must contribute to genomic instability in dividing iECs. Overall our results suggest that transient endoreplication cycles generate a diverse population of proliferative aneuploid cells that have the potential to contribute to tumor heterogeneity.


Asunto(s)
Inestabilidad Cromosómica/genética , Cinesinas/metabolismo , Aneuploidia , Línea Celular , Línea Celular Tumoral , Proliferación Celular , Centrosoma/metabolismo , Centrosoma/fisiología , Inestabilidad Cromosómica/fisiología , Cromosomas , Regulación hacia Abajo , Endorreduplicación/genética , Inestabilidad Genómica/genética , Inestabilidad Genómica/fisiología , Humanos , Cinesinas/genética , Mitosis/genética , Poliploidía , Huso Acromático/metabolismo , Polos del Huso/metabolismo
14.
J Cell Sci ; 127(Pt 22): 4833-45, 2014 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-25236602

RESUMEN

Wnt-ß-catenin (ß-catenin is also known as CTNNB1 in human) signaling through the ß-catenin-TCF complex plays crucial roles in tissue homeostasis. Wnt-stimulated ß-catenin-TCF complex accumulation in the nucleus regulates cell survival, proliferation and differentiation through the transcription of target genes. Compared with their levels in G1, activation of the receptor LRP6 and cytosolic ß-catenin are both upregulated in G2 cells. However, accumulation of the Wnt pathway negative regulator AXIN2 also occurs in this phase. Therefore, it is unclear whether Wnt signaling is active in G2 phase cells. Here, we established a bimolecular fluorescence complementation (BiFC) biosensor system for the direct visualization of the ß-catenin-TCF interaction in living cells. Using the BiFC biosensor and co-immunoprecipitation experiments, we demonstrate that levels of the nucleus-localized ß-catenin-TCF complex increase during the S and G2 phases, and declines in the next G1 phase. Accordingly, a subset of Wnt target genes is transcribed by the ß-catenin-TCF complex during both the S and G2 phases. By contrast, transient inhibition of this complex disturbs both cell survival and G2/M progression. Our results suggest that in S and G2 phase cells, Wnt-ß-catenin signaling is highly active and functions to ensure cell survival and cell cycle progression.


Asunto(s)
Fase G2/fisiología , Fase S/fisiología , beta Catenina/metabolismo , Línea Celular Tumoral , Núcleo Celular/metabolismo , Supervivencia Celular/fisiología , Expresión Génica , Células HeLa , Humanos , Transducción de Señal , Transcripción Genética , Activación Transcripcional , beta Catenina/genética
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