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1.
Nat Mater ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641696

RESUMO

Symmetry breaking in quantum materials is of great importance and can lead to non-reciprocal charge transport. Topological insulators provide a unique platform to study non-reciprocal charge transport due to their surface states, especially quantum Hall states under an external magnetic field. Here we report the observation of non-reciprocal charge transport mediated by quantum Hall states in devices composed of the intrinsic topological insulator Sn-Bi1.1Sb0.9Te2S, which is attributed to asymmetric scattering between quantum Hall states and Dirac surface states. A giant non-reciprocal coefficient of up to 2.26 × 105 A-1 is found. Our work not only reveals the properties of non-reciprocal charge transport of quantum Hall states in topological insulators but also paves the way for future electronic devices.

2.
BMC Genomics ; 25(1): 321, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38556880

RESUMO

Congenital infection caused by vertical transmission of microsporidia N. bombycis can result in severe economic losses in the silkworm-rearing industry. Whole-transcriptome analyses have revealed non-coding RNAs and their regulatory networks in N. bombycis infected embryos and larvae. However, transcriptomic changes in the microsporidia proliferation and host responses in congenitally infected embryos and larvae remains unclear. Here, we simultaneously compared the transcriptomes of N. bombycis and its host B. mori embryos of 5-day and larvae of 1-, 5- and 10-day during congenital infection. For the transcriptome of N. bombycis, a comparison of parasite expression patterns between congenital-infected embryos and larva showed most genes related to parasite central carbon metabolism were down-regulated in larvae during infection, whereas the majority of genes involved in parasite proliferation and growth were up-regulated. Interestingly, a large number of distinct or shared differentially expressed genes (DEGs) were revealed by the Venn diagram and heat map, many of them were connected to infection related factors such as Ricin B lectin, spore wall protein, polar tube protein, and polysaccharide deacetylase. For the transcriptome of B. mori infected with N. bombycis, beyond numerous DEGs related to DNA replication and repair, mRNA surveillance pathway, RNA transport, protein biosynthesis, and proteolysis, with the progression of infection, a large number of DEGs related to immune and infection pathways, including phagocytosis, apoptosis, TNF, Toll-like receptor, NF-kappa B, Fc epsilon RI, and some diseases, were successively identified. In contrast, most genes associated with the insulin signaling pathway, 2-oxacarboxylic acid metabolism, amino acid biosynthesis, and lipid metabolisms were up-regulated in larvae compared to those in embryos. Furthermore, dozens of distinct and three shared DEGs that were involved in the epigenetic regulations, such as polycomb, histone-lysine-specific demethylases, and histone-lysine-N-methyltransferases, were identified via the Venn diagram and heat maps. Notably, many DEGs of host and parasite associated with lipid-related metabolisms were verified by RT-qPCR. Taken together, simultaneous transcriptomic analyses of both host and parasite genes lead to a better understanding of changes in the microsporidia proliferation and host responses in embryos and larvae in N. bombycis congenital infection.


Assuntos
Bombyx , Nosema , Animais , Transcriptoma , Larva/genética , Larva/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Nosema/fisiologia , Perfilação da Expressão Gênica , Proliferação de Células , Lipídeos , Bombyx/genética
3.
Artigo em Inglês | MEDLINE | ID: mdl-38564118

RESUMO

The present study was conducted to develop a green process that provides access to the development of Schiff base derivatives of chitosan with the heterocyclic moiety as a novel class of anti-gastric cancer agent. In the present study, we have synthesized these derivatives by reacting various pyrazoles with chitosan using CAN in PEG400. The compounds were synthesized in 20 min in excellent yield by using CAN at 5% in PEG400 at 80°C in the shortest reaction time of 20 min. The PEG400 could be efficiently recycled for the three consecutive runs. The developed compounds were tested for EGFR-TK inhibition using a Kinase-Glo Plus luminescence kinase assay kit where they exhibited significant activity revealing compound 2d as the most potent analog, while other compounds showed mild to moderate inhibitory activity. MTT assay was conducted to determine the effect of the three most potent EGFR inhibitors (2b, 2c, and 2d) on the proliferation of gastric cancer cells (SGC-7901). The results showed compound 2d as the most potent anticancer agent against SGC7901 cells. The effect of compound 2d was also quantified on the apoptosis and cell phase of SGC7901 cells using flow cytometry assay at various concentrations ranging from 0, 10, 20, and 30 µM. Results suggest that compound 2d showed significant inhibition of SGC-7901 by inducing apoptosis and arresting G0/G1 cell phase. The western blot analysis also revealed that compound 2d significantly inhibited the overexpression of EGFR in SGC-7901 cells. The study successfully demonstrated the development of N­pyrazole amino chitosan as a novel class of agent against gastric cancer via inhibition of EGFR.

4.
mBio ; 15(2): e0274923, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38193684

RESUMO

Microsporidia are obligate intracellular parasites that infect a wide variety of hosts including humans. Microsporidian spores possess a unique, highly specialized invasion apparatus involving the polar filament, polaroplast, and posterior vacuole. During spore germination, the polar filament is discharged out of the spore forming a hollow polar tube that transports the sporoplasm components including the nucleus into the host cell. Due to the complicated topological changes occurring in this process, the details of sporoplasm formation are not clear. Our data suggest that the limiting membrane of the nascent sporoplasm is formed by the polaroplast after microsporidian germination. Using electron microscopy and 1,1'-dioctadecyl-3,3,3',3' tetramethyl indocarbocyanine perchlorate staining, we describe that a large number of vesicles, nucleus, and other cytoplasm contents were transported out via the polar tube during spore germination, while the posterior vacuole and plasma membrane finally remained in the empty spore coat. Two Nosema bombycis sporoplasm surface proteins (NbTMP1 and NoboABCG1.1) were also found to localize in the region of the polaroplast and posterior vacuole in mature spores and in the discharged polar tube, which suggested that the polaroplast during transport through the polar tube became the limiting membrane of the sporoplasm. The analysis results of Golgi-tracker green and Golgi marker protein syntaxin 6 were also consistent with the model of the transported polaroplast derived from Golgi transformed into the nascent sporoplasm membrane.IMPORTANCEMicrosporidia, which are obligate intracellular pathogenic organisms, cause huge economic losses in agriculture and even threaten human health. The key to successful infection by the microsporidia is their unique invasion apparatus which includes the polar filament, polaroplast, and posterior vacuole. When the mature spore is activated to geminate, the polar filament uncoils and undergoes a rapid transition into the hollow polar tube that transports the sporoplasm components including the microsporidian nucleus into host cells. Details of the structural difference between the polar filament and polar tube, the process of cargo transport in extruded polar tube, and the formation of the sporoplasm membrane are still poorly understood. Herein, we verify that the polar filament evaginates to form the polar tube, which serves as a conduit for transporting the nucleus and other sporoplasm components. Furthermore, our results indicate that the transported polaroplast transforms into the sporoplasm membrane during spore germination. Our study provides new insights into the cargo transportation process of the polar tube and origin of the sporoplasm membrane, which provide important clarification of the microsporidian infection mechanism.


Assuntos
Microsporídios , Humanos , Esporos Fúngicos , Citoplasma , Microscopia Eletrônica , Membrana Celular , Bandagens
5.
Nat Chem Biol ; 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38225471

RESUMO

A major challenge in creating universal influenza vaccines is to focus immune responses away from the immunodominant, variable head region of hemagglutinin (HA-head) and toward the evolutionarily conserved stem region (HA-stem). Here we introduce an approach to control antigen orientation via site-specific insertion of aspartate residues that facilitates antigen binding to alum. We demonstrate the generalizability of this approach with antigens from Ebola, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and influenza viruses and observe enhanced neutralizing antibody responses in all cases. We then reorient an H2 HA in an 'upside-down' configuration to increase the exposure and immunogenicity of HA-stem. The reoriented H2 HA (reoH2HA) on alum induced stem-directed antibodies that cross-react with both group 1 and group 2 influenza A subtypes. Electron microscopy polyclonal epitope mapping (EMPEM) revealed that reoH2HA (group 1) elicits cross-reactive antibodies targeting group 2 HA-stems. Our results highlight antigen reorientation as a generalizable approach for designing epitope-focused vaccines.

6.
Sensors (Basel) ; 24(1)2024 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-38203165

RESUMO

When the workpiece surface exhibits strong reflectivity, it becomes challenging to obtain accurate key measurements using non-contact, visual measurement techniques due to poor image quality. In this paper, we propose a high-precision measurement method shaft diameter based on an enhanced quality stripe image. By capturing two stripe images with different exposure times, we leverage their different characteristics. The results extracted from the low-exposure image are used to perform grayscale correction on the high-exposure image, improving the distribution of stripe grayscale and resulting in more accurate extraction results for the center points. The incorporation of different measurement positions and angles further enhanced measurement precision and robustness. Additionally, ellipse fitting is employed to derive shaft diameter. This method was applied to the profiles of different cross-sections and angles within the same shaft segment. To reduce the shape error of the shaft measurement, the average of these measurements was taken as the estimate of the average diameter for the shaft segment. In the experiments, the average shaft diameters determined by averaging elliptical estimations were compared with shaft diameters obtained using a coordinate measuring machine (CMM) the maximum error and the minimum error were respectively 18 µm and 7 µm; the average error was 11 µm; and the root mean squared error of the multiple measurement results was 10.98 µm. The measurement accuracy achieved is six times higher than that obtained from the unprocessed stripe images.

7.
Nat Immunol ; 25(1): 41-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036767

RESUMO

Bacille Calmette-Guérin (BCG) vaccination can confer nonspecific protection against heterologous pathogens. However, the underlying mechanisms remain mysterious. We show that mice vaccinated intravenously with BCG exhibited reduced weight loss and/or improved viral clearance when challenged with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2 B.1.351) or PR8 influenza. Protection was first evident between 14 and 21 d post-vaccination and lasted ∼3 months. Notably, BCG induced a biphasic innate response and robust antigen-specific type 1 helper T cell (TH1 cell) responses in the lungs. MyD88 signaling was essential for innate and TH1 cell responses, and protection against SARS-CoV-2. Depletion of CD4+ T cells or interferon (IFN)-γ activity before infection obliterated innate activation and protection. Single-cell and spatial transcriptomics revealed CD4-dependent expression of IFN-stimulated genes in lung myeloid and epithelial cells. Notably, BCG also induced protection against weight loss after mouse-adapted SARS-CoV-2 BA.5, SARS-CoV and SHC014 coronavirus infections. Thus, BCG elicits integrated organ immunity, where CD4+ T cells feed back on tissue myeloid and epithelial cells to imprint prolonged and broad innate antiviral resistance.


Assuntos
Imunidade Adaptativa , Vacina BCG , Animais , Camundongos , Humanos , Retroalimentação , Vacinação , Redução de Peso , Antivirais , Imunidade Inata
8.
PLoS Pathog ; 19(12): e1011859, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38060601

RESUMO

Microsporidia are a group of obligate intracellular parasites that infect almost all animals, causing serious human diseases and major economic losses to the farming industry. Nosema bombycis is a typical microsporidium that infects multiple lepidopteran insects via fecal-oral and transovarial transmission (TOT); however, the underlying TOT processes and mechanisms remain unknown. Here, we characterized the TOT process and identified key factors enabling N. bombycis to invade the ovariole and oocyte of silkworm Bombyx mori. We found that the parasites commenced with TOT at the early pupal stage when ovarioles penetrated the ovary wall and were exposed to the hemolymph. Subsequently, the parasites in hemolymph and hemolymph cells firstly infiltrated the ovariole sheath, from where they invaded the oocyte via two routes: (I) infecting follicular cells, thereby penetrating oocytes after proliferation, and (II) infecting nurse cells, thus entering oocytes following replication. In follicle and nurse cells, the parasites restructured and built large vacuoles to deliver themselves into the oocyte. In the whole process, the parasites were coated with B. mori vitellogenin (BmVg) on their surfaces. To investigate the BmVg effects on TOT, we suppressed its expression and found a dramatic decrease of pathogen load in both ovarioles and eggs, suggesting that BmVg plays a crucial role in the TOT. Thereby, we identified the BmVg domains and parasite spore wall proteins (SWPs) mediating the interaction, and demonstrated that the von Willebrand domain (VWD) interacted with SWP12, SWP26 and SWP30, and the unknown function domain (DUF1943) bound with the SWP30. When disrupting these interactions, we found significant reductions of the pathogen load in both ovarioles and eggs, suggesting that the interplays between BmVg and SWPs were vital for the TOT. In conclusion, our study has elucidated key aspects about the microsporidian TOT and revealed the key factors for understanding the molecular mechanisms underlying this transmission.


Assuntos
Bombyx , Nosema , Animais , Humanos , Vitelogeninas/metabolismo , Esporos Fúngicos/metabolismo , Nosema/metabolismo , Bombyx/metabolismo
9.
Insects ; 14(12)2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38132605

RESUMO

Lepidoptera is one of the most speciose insect orders, causing enormous damage to agricultural and forest crops. Although genome editing has been achieved in a few Lepidoptera for insect controls, most techniques are still limited. Here, by injecting female pupae of the Lepidoptera model species, Bombyx mori, gene editing was established using the Receptor-Mediated Ovary Transduction of Cargo (ReMOT) control technique. We identified a B. mori oocytes-targeting peptide ligand (BmOTP, a 29 aa of vitellogenin N-terminal of silkworms) with a highly conserved sequence in lepidopteran insects that could efficiently deliver mCherry into oocytes. When BmOTP was fused to CRISPR-associated protein 9 (Cas9) and the BmOTP-Cas9 ribonucleoprotein complex was injected into female pupae, heritable editing of the offspring was achieved in the silkworms. Compared with embryo microinjection, individual injection is more convenient and eliminates the challenge of injecting extremely small embryos. Our results will significantly facilitate the genetic manipulation of other lepidopteran insects, which is essential for advancing lepidopteran pest control.

10.
Polymers (Basel) ; 15(21)2023 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-37959927

RESUMO

In order to overcome the defects of fast-growing poplar wood, such as low strength and poor toughness, this paper introduces a method of modifying poplar wood via impregnation with silica sol/melamine-glyoxal (silica sol/MG) resin and explores its effects on the physical, mechanical, and thermal properties of poplar wood. It was found via scanning electron microscopy that the composite modifier covered and filled the cell lumen, cell interstitial space, and cell wall pores of poplar wood. Further, infrared spectroscopy and X-ray photoelectron spectroscopy analyses confirmed that chemical cross-linking occurred between the silica sol/MG resin composite modifier and the internal groups of poplar wood and that the Si-O-Si flexible long chains introduced in the composite modifier formed a cross-linking network with poplar wood such as Si-O-Si and Si-O-C, which led to the improvement of the physical and mechanical properties and the enhancement of the thermal stability of poplar wood. The method provides a theoretical basis for the high-value utilization of fast-growing poplar wood.

11.
Microbiol Spectr ; 11(6): e0068123, 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-37811955

RESUMO

IMPORTANCE: There are a few reports on the resistance of microsporidia, including Nosema bombycis. Here, the alkali-soluble germination proteins of N. bombycis were used as immunogens to prepare a monoclonal antibody, and its single-chain variable fragments effectively blocked microsporidia infection. Our study has provided novel strategies for microsporidiosis control and demonstrated a useful method for the potential treatment of other microsporidia diseases.


Assuntos
Bombyx , Microsporidiose , Nosema , Animais , Bombyx/metabolismo , Anticorpos Monoclonais , Esporos , Proliferação de Células
12.
Cancer Control ; 30: 10732748231202466, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37728233

RESUMO

BACKGROUND: Tumor markers (TMs) are important for the prognosis of gastric cancer (GC). However, the prognostic importance of the tumor marker index (TMI) based on GC-specific TMs for advanced gastric cancer (AGC) still needs to be further explored. METHODS: We retrospectively examined patients who underwent radical gastric cancer surgery between February 2014 and June 2016 at the Department of Gastroenterological Surgery, Affiliated Cancer Hospital, Harbin Medical University. The patients were divided into training and validation groups. TMI was determined as the geometric mean of the standard cancer antigen 19-9 (CA19-9) and carcinoembryonic antigen (CEA) levels. Patient overall survival was assessed using the Kaplan-Meier method. Independent prognosis-associated risk factors were identified using Cox hazard regression models. A nomogram model incorporating TMI and clinicopathological factors was developed, and its performance was evaluated using a decision curve analysis, concordance index, and calibration plots. RESULTS: In the TMI training cohort, the cutoff value was set at .439, categorizing patients into TMI-High and TMI-Low groups. The 5-year survival rate in the TMI-Low group significantly surpassed that in the TMI-High group (78.2% vs 58.1% and 49.7 vs 41.6, P < .001). TMI emerged as an independent prognostic factor. The nomogram accurately predicted patient prognosis by using TMI and clinicopathological characteristics. Validation of the TMI in the independent cohort yielded satisfactory results. CONCLUSION: The TMI constructed based on specific TMs associated with gastric cancer can offer a precise prognostic prediction for patients.


Assuntos
Biomarcadores Tumorais , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/patologia , Estadiamento de Neoplasias , Estudos Retrospectivos , Prognóstico
13.
BMC Genomics ; 24(1): 420, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37495972

RESUMO

BACKGROUND: The interaction networks between coding and non-coding RNAs (ncRNAs) including long non-coding RNA (lncRNA), covalently closed circular RNA (circRNA) and miRNA are significant to elucidate molecular processes of biological activities and interactions between host and pathogen. Congenital infection caused by vertical transmission of microsporidia N. bombycis can result in severe economic losses in the silkworm-feeding industry. However, little is known about ncRNAs that take place in the microsporidia congenital infection. Here we conducted whole-transcriptome RNA-Seq analyses to identify ncRNAs and regulatory networks for both N. bombycis and host including silkworm embryos and larvae during the microsporidia congenital infection. RESULTS: A total of 4,171 mRNAs, 403 lncRNA, 62 circRNAs, and 284 miRNAs encoded by N. bombycis were identified, among which some differentially expressed genes formed cross-talk and are involved in N. bombycis proliferation and infection. For instance, a lncRNA/circRNA competing endogenous RNA (ceRNA) network including 18 lncRNAs, one circRNA, and 20 miRNAs was constructed to describe 14 key parasites genes regulation, such as polar tube protein 3 (PTP3), ricin-B-lectin, spore wall protein 4 (SWP4), and heat shock protein 90 (HSP90). Regarding host silkworm upon N. bombycis congenital infection, a total of 14,889 mRNAs, 3,038 lncRNAs, 19,039 circRNAs, and 3,413 miRNAs were predicted based on silkworm genome with many differentially expressed coding and non-coding genes during distinct developmental stages. Different species of RNAs form interacting network to modulate silkworm biological processes, such as growth, metamorphosis and immune responses. Furthermore, a lncRNA/circRNA ceRNA network consisting of 140 lncRNAs, five circRNA, and seven miRNAs are constructed hypothetically to describe eight key host genes regulation, such as Toll-6, Serpin-6, inducible nitric oxide synthase (iNOS) and Caspase-8. Notably, cross-species analyses indicate that parasite and host miRNAs play a vital role in pathogen-host interaction in the microsporidia congenital infection. CONCLUSION: This is the first comprehensive pan-transcriptome study inclusive of both N. bombycis and its host silkworm with a specific focus on the microsporidia congenital infection, and show that ncRNA-mediated regulation plays a vital role in the microsporidia congenital infection, which provides a new insight into understanding the basic biology of microsporidia and pathogen-host interaction.


Assuntos
MicroRNAs , Microsporidiose , Nosema , RNA Longo não Codificante , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , RNA Circular/genética , Nosema/fisiologia , Interações Hospedeiro-Patógeno/genética , MicroRNAs/genética , RNA Mensageiro , Redes Reguladoras de Genes
14.
Int J Mol Sci ; 24(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37373428

RESUMO

Melanin is a complex natural pigment that is widely present in fungi. The mushroom Ophiocordyceps sinensis has a variety of pharmacological effects. The active substances of O. sinensis have been extensively studied, but few studies have focused on the O. sinensis melanin. In this study, the production of melanin was increased by adding light or oxidative stress, namely, reactive oxygen species (ROS) or reactive nitrogen species (RNS), during liquid fermentation. Subsequently, the structure of the purified melanin was characterized using elemental analysis, ultraviolet-visible absorption spectrum, Fourier transform infrared (FTIR), electron paramagnetic resonance (EPR), and pyrolysis gas chromatography and mass spectrometry (Py-GCMS). Studies have shown that O. sinensis melanin is composed of C (50.59), H (6.18), O (33.90), N (8.19), and S (1.20), with maximum absorbance at 237 nm and typical melanin structures such as benzene, indole, and pyrrole. Additionally, the various biological activities of O. sinensis melanin have been discovered; it can chelate heavy metals and shows a strong ultraviolet-blocking ability. Moreover, O. sinensis melanin can reduce the levels of intracellular reactive oxygen species and counteract the oxidative damage of H2O2 to cells. These results can help us to develop applications of O. sinensis melanin in radiation resistance, heavy metal pollution remediation, and antioxidant use.


Assuntos
Agaricales , Cordyceps , Cordyceps/química , Melaninas/química , Espécies Reativas de Oxigênio , Peróxido de Hidrogênio
15.
Materials (Basel) ; 16(9)2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37176476

RESUMO

In order to study the influence of vinyl acetate-ethylene copolymerization emulsions on the bonding performance of fiber and mortar, mortar materials with different polymer contents were prepared. The optimal mix ratio of the matrix was obtained using a pull-out test with a 0° inclination angle. On this basis, polypropylene fibers and alkali-resistant glass fibers were set at different burial depths (6 mm, 12 mm, and 18 mm) and different burial angles (0°, 30°, 45°, and 60°). The load-displacement curves of two types of fibers pulled out from the polymer mortar were obtained. The test results show that polymer contents of 3% and 5% increase the peak pull-out loads of glass fibers and polypropylene fibers by 16.28% and 30.72% and 7.41% and 27.11%, respectively. When the polymer content is 7%, the peak pull-out load decreases by 1.31% and 24.26%, especially for polypropylene fiber, which significantly weakens the bonding performance between the matrix and the fiber. The pull-out load of glass fibers and polypropylene fibers increases with the increase in the buried depth, and both show tensile failure at 18 mm. As the embedding angle increases, the pull-out load of polypropylene fibers decreases continuously, while the glass fiber shows a higher pull-out load at 30°.

17.
J Invertebr Pathol ; 198: 107937, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37209810

RESUMO

Bombyx mori nucleopolyhedrovirus (BmNPV) poses a significant threat to sericulture production, and traditional sanitation practices remain the main strategy for controlling BmNPV infection. Although RNAi targeting BmNPV genes engineered into transgenic silkworms has shown to be a promising approach in reducing viral infection, it cannot block viral entry into host cells. Therefore, there is an urgent need to develop new effective prevention and control measures. In this study, we screened a monoclonal antibody 6C5 that potently neutralizes BmNPV infection by clamping the internal fusion loop of the BmNPVglycoprotein64 (GP64). Furthermore, we cloned the VH and VL fragments of mAb-6C5 from the hybridoma cell, and the eukaryotic expression vector of scFv6C5 was constructed to anchor the antibody on the cell membrane. The GP64 fusion loop antibody-expressing cells exhibited a reduced capacity for BmNPV infection. The results from our study provide a novel BmNPV control strategy and lay the foundation for the future development of transgenic silkworms with improved antiviral efficacy.


Assuntos
Bombyx , Nucleopoliedrovírus , Animais , Nucleopoliedrovírus/genética , Animais Geneticamente Modificados , Interferência de RNA , Membrana Celular
18.
PLoS One ; 18(4): e0284486, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37079619

RESUMO

The molecular mechanism of Chinese cordyceps formation has received a substantial amount of attention because of its usage as traditional Chinese medicine. The formation process of Chinese cordyceps includes two parts: asexual proliferation (Ophiocordyceps sinensis proliferates in the hemolymph of Thitarodes armoricanus larvae) and sexual development (formation and development of fruiting bodies). Therefore, validation of reference genes under different development stages and experimental conditions is crucial for RT-qPCR analysis. However, there is no report on stable reference genes at the development stage of O. sinensis fruiting body. In this study, 10 candidate reference genes, Actin, Cox5, Tef1, Ubi, 18s, Gpd, Rpb1, Try, Tub1 and Tub2, were selected and calculated their expression stability using four methods: geNorm, NormFinder, BestKeeper, and Comparative △Ct. After comprehensive analysis of the results of these four methods with RefFinder, we determined that the most stable reference genes during asexual reproduction of O. sinensis were Tef1 and Tub1, while the most stable reference genes during fruiting body development were Tyr and Cox5, and the most stable reference genes under light-induced conditions were Tyr and Tef1. Our study provides a guidance for reference genes selections at different proliferation processes with light stress of O. sinensis, and represents a foundation for studying the molecular mechanism of Chinese cordyceps formation.


Assuntos
Cordyceps , Mariposas , Animais , Cordyceps/genética , Cordyceps/metabolismo , Mariposas/genética , Larva/genética , Desenvolvimento Sexual , Expressão Gênica , Perfilação da Expressão Gênica , Padrões de Referência
19.
Front Cell Dev Biol ; 11: 1110271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910162

RESUMO

Coronavirus disease 2019 (COVID-19) is associated with adverse impacts in the cardiovascular system, but the mechanisms driving this response remain unclear. In this study, we conducted "pseudoviral infection" of SARS-CoV-2 subunits to evaluate their toxic effects in cardiomyocytes (CMs), that were derived from human induced pluripotent stem cells (hiPSCs). We found that the ectopic expression of S and ORF-9B subunits significantly impaired the contractile function and altered the metabolic profiles in human cardiomyocytes. Further mechanistic study has shown that the mitochondrial oxidative phosphorylation (OXPHOS), membrane potential, and ATP production were significantly decreased two days after the overexpression of S and ORF-9B subunits, while S subunits induced higher level of reactive oxygen species (ROS). Two weeks after overexpression, glycolysis was elevated in the ORF-9B group. Based on the transcriptomic analysis, both S and ORF-9B subunits dysregulated signaling pathways associated with metabolism and cardiomyopathy, including upregulated genes involved in HIF-signaling and downregulated genes involved in cholesterol biosynthetic processes. The ORF-9B subunit also enhanced glycolysis in the CMs. Our results collectively provide an insight into the molecular mechanisms underlying SARS-CoV-2 subunits-induced metabolic alterations and cardiac dysfunctions in the hearts of COVID-19 patients.

20.
Immunity ; 56(4): 864-878.e4, 2023 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-36996809

RESUMO

T cells are a critical component of the response to SARS-CoV-2, but their kinetics after infection and vaccination are insufficiently understood. Using "spheromer" peptide-MHC multimer reagents, we analyzed healthy subjects receiving two doses of the Pfizer/BioNTech BNT162b2 vaccine. Vaccination resulted in robust spike-specific T cell responses for the dominant CD4+ (HLA-DRB1∗15:01/S191) and CD8+ (HLA-A∗02/S691) T cell epitopes. Antigen-specific CD4+ and CD8+ T cell responses were asynchronous, with the peak CD4+ T cell responses occurring 1 week post the second vaccination (boost), whereas CD8+ T cells peaked 2 weeks later. These peripheral T cell responses were elevated compared with COVID-19 patients. We also found that previous SARS-CoV-2 infection resulted in decreased CD8+ T cell activation and expansion, suggesting that previous infection can influence the T cell response to vaccination.


Assuntos
COVID-19 , Vacinas , Humanos , Linfócitos T CD8-Positivos , Vacina BNT162 , SARS-CoV-2 , Vacinação , Anticorpos Antivirais
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