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1.
Nature ; 594(7861): 41-45, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34079139

RESUMEN

Owing to the inevitable loss in communication channels, the distance of entanglement distribution is limited to approximately 100 kilometres on the ground1. Quantum repeaters can circumvent this problem by using quantum memory and entanglement swapping2. As the elementary link of a quantum repeater, the heralded distribution of two-party entanglement between two remote nodes has only been realized with built-in-type quantum memories3-9. These schemes suffer from the trade-off between multiplexing capacity and deterministic properties and hence hinder the development of efficient quantum repeaters. Quantum repeaters based on absorptive quantum memories can overcome such limitations because they separate the quantum memories and the quantum light sources. Here we present an experimental demonstration of heralded entanglement between absorptive quantum memories. We build two nodes separated by 3.5 metres, each containing a polarization-entangled photon-pair source and a solid-state quantum memory with bandwidth up to 1 gigahertz. A joint Bell-state measurement in the middle station heralds the successful distribution of maximally entangled states between the two quantum memories with a fidelity of 80.4 ± 2.2 per cent (±1 standard deviation). The quantum nodes and channels demonstrated here can serve as an elementary link of a quantum repeater. Moreover, the wideband absorptive quantum memories used in the nodes are compatible with deterministic entanglement sources and can simultaneously support multiplexing, which paves the way for the construction of practical solid-state quantum repeaters and high-speed quantum networks.

2.
Mol Cell ; 70(4): 602-613.e3, 2018 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-29775578

RESUMEN

The proteolysis-assisted protein quality control system guards the proteome from potentially detrimental aberrant proteins. How miscellaneous defective proteins are specifically eliminated and which molecular characteristics direct them for removal are fundamental questions. We reveal a mechanism, DesCEND (destruction via C-end degrons), by which CRL2 ubiquitin ligase uses interchangeable substrate receptors to recognize the unusual C termini of abnormal proteins (i.e., C-end degrons). C-end degrons are mostly less than ten residues in length and comprise a few indispensable residues along with some rather degenerate ones. The C-terminal end position is essential for C-end degron function. Truncated selenoproteins generated by translation errors and the USP1 N-terminal fragment from post-translational cleavage are eliminated by DesCEND. DesCEND also targets full-length proteins with naturally occurring C-end degrons. The C-end degron in DesCEND echoes the N-end degron in the N-end rule pathway, highlighting the dominance of protein "ends" as indicators for protein elimination.


Asunto(s)
Procesamiento Proteico-Postraduccional , Receptores de Citocinas/metabolismo , Selenoproteínas/metabolismo , Proteasas Ubiquitina-Específicas/metabolismo , Ubiquitina/metabolismo , Células HEK293 , Células HeLa , Células Hep G2 , Humanos , Dominios Proteicos , Proteolisis , Receptores de Citocinas/genética , Proteasas Ubiquitina-Específicas/genética
3.
J Med Virol ; 96(2): e29439, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38294104

RESUMEN

Hepatitis B virus (HBV) infection is a serious global health problem. After the viruses infect the human body, the host can respond to the virus infection by coordinating various cellular responses, in which mitochondria play an important role. Evidence has shown that mitochondrial proteins are involved in host antiviral responses. In this study, we found that the overexpression of TIM22 and TIM29, the members of the inner membrane translocase TIM22 complex, significantly reduced the level of intracellular HBV DNA and RNA and secreted HBV surface antigens and E antigen. The effects of TIM22 and TIM29 on HBV replication and transcription is attributed to the reduction of core promoter activity mediated by the increased expression of SRSF1 which acts as a suppressor of HBV replication. This study provides new evidence for the critical role of mitochondria in the resistance of HBV infection and new targets for the development of treatment against HBV infection.


Asunto(s)
Virus de la Hepatitis B , Hepatitis B , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Factores de Empalme Serina-Arginina , Humanos , Antígenos e de la Hepatitis B/genética , Antígenos e de la Hepatitis B/metabolismo , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/fisiología , Factores de Empalme Serina-Arginina/metabolismo , Replicación Viral , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales/metabolismo
4.
J Vasc Interv Radiol ; 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38663515

RESUMEN

PURPOSE: To investigate the safety and feasibility of renal artery coil embolization for establishing chronic kidney disease (CKD) in rabbits. MATERIALS AND METHODS: Ten male adult New Zealand rabbits underwent renal artery coil embolization. Initially, the main renal artery on 1 side was completely embolized, followed by embolization of approximately two-thirds of the primary branches of the contralateral renal artery 1 week later. Four rabbits were randomly chosen for sacrifice at 4 weeks after embolization, whereas the remaining 6 were sacrificed at 8 weeks after embolization. The assessment encompassed the animals' general condition, angiography, biochemical parameters, inflammatory markers, and histopathological examination of the kidneys and hearts. RESULTS: Four weeks after embolization, serum creatinine level showed a substantial increase (2.4 mg/dL [SD ± 0.6]; P = .009 vs baseline), with a subsequent 4.12-fold elevation at 8 weeks after embolization (4.9 mg/dL [SD ± 1.4]; P < .001 vs baseline). Additionally, considerable increases in serum blood urea nitrogen, calcium, and potassium ions were observed at 8 weeks after embolization (58.3 mg/dL [SD ± 19.0]; P < .001 vs baseline; 23.1 mg/dL [SD ± 4.4]; P < .001 vs baseline; and 6.3 mEq/L [SD ± 0.7]; P < .001 vs baseline, respectively). The completely embolized kidney exhibited notable atrophy, severe fibrosis, and cortical calcification, whereas the contralateral partially embolized kidney displayed compensatory hypertrophy, along with glomerulosclerosis, tubular dilation, tubular casts, and interstitial fibrosis. CONCLUSIONS: Renal artery coil embolization proved to be effective and safe for establishing a CKD model in rabbits.

5.
Cell ; 136(5): 852-64, 2009 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-19269364

RESUMEN

Initiation of eukaryotic DNA synthesis occurs at origins of replication that are utilized with characteristic times and frequencies during S phase. We have investigated origin usage by evaluating the kinetics of replication factor binding in fission yeast and show that similar to metazoa, ORC binding is periodic during the cell cycle, increasing during mitosis and peaking at M/G1. At an origin, the timing of ORC binding in M and pre-RC assembly in G1 correlates with the timing of firing during S, and the level of pre-IC formation reflects origin efficiency. Extending mitosis allows ORC to become more equally associated with origins and leads to genome-wide changes in origin usage, while overproduction of pre-IC factors increases replication of both efficient and inefficient origins. We propose that differential recruitment of ORC to origins during mitosis followed by competition among origins for limiting replication factors establishes the timing and efficiency of origin firing.


Asunto(s)
Replicación del ADN , Origen de Réplica , Fase S , Schizosaccharomyces/metabolismo , Proteínas de Ciclo Celular/metabolismo , ADN de Hongos/genética , Proteínas de Unión al ADN/metabolismo , Proteínas Nucleares/metabolismo , Schizosaccharomyces/citología , Schizosaccharomyces/genética , Proteínas de Schizosaccharomyces pombe/metabolismo
6.
Proc Natl Acad Sci U S A ; 118(10)2021 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-33653947

RESUMEN

Pancreatic ductal adenocarcinoma (PDA) is a lethal, therapy-resistant cancer that thrives in a highly desmoplastic, nutrient-deprived microenvironment. Several studies investigated the effects of depriving PDA of either glucose or glutamine alone. However, the consequences on PDA growth and metabolism of limiting both preferred nutrients have remained largely unknown. Here, we report the selection for clonal human PDA cells that survive and adapt to limiting levels of both glucose and glutamine. We find that adapted clones exhibit increased growth in vitro and enhanced tumor-forming capacity in vivo. Mechanistically, adapted clones share common transcriptional and metabolic programs, including amino acid use for de novo glutamine and nucleotide synthesis. They also display enhanced mTORC1 activity that prevents the proteasomal degradation of glutamine synthetase (GS), the rate-limiting enzyme for glutamine synthesis. This phenotype is notably reversible, with PDA cells acquiring alterations in open chromatin upon adaptation. Silencing of GS suppresses the enhanced growth of adapted cells and mitigates tumor growth. These findings identify nongenetic adaptations to nutrient deprivation in PDA and highlight GS as a dependency that could be targeted therapeutically in pancreatic cancer patients.


Asunto(s)
Carcinoma Ductal Pancreático/metabolismo , Glutamato-Amoníaco Ligasa/metabolismo , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Línea Celular Tumoral , Estabilidad de Enzimas , Glutamato-Amoníaco Ligasa/genética , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina/genética , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética
7.
Pestic Biochem Physiol ; 201: 105879, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38685245

RESUMEN

The fall armyworm (FAW), Spodoptera frugiperda (J.E. Smith) (Lepidoptera, Noctuidae), is a highly polyphagous invasive pest that damages various crops. Pesticide control is the most common and effective strategy to control FAW. In this study, we evaluated the toxicity of metaflumizone and indoxacarb against third-instar FAW larvae using the insecticide-incorporated artificial diet method under laboratory conditions. Both metaflumizone and indoxacarb exhibited substantial toxicity against FAW, with LC50 values of 2.43 and 14.66 mg/L at 72 h, respectively. The sublethal effects of metaflumizone and indoxacarb on parental and F1 generation FAW were investigated by exposing third-instar larvae to LC10 and LC30 concentrations of these insecticides. Sublethal exposure to these two insecticides significantly shortened adult longevity, extended pupal developmental times and led to reduced pupal weight, pupation rates, and adult fecundity in the treated parental generation and F1 generation at LC10 or LC30 concentrations, in comparison to the control group. The larval developmental times were shortened in the parental generation but prolonged in the F1 generation, after being treated with sublethal concentrations of metaflumizone. Furthermore, larvae exposed to LC10 or LC30 concentrations of indoxacarb exhibited elevated activity levels of cytochrome P450 monooxygenase and glutathione S-transferase, which coincides with the observed synergistic effect of piperonyl butoxide and diethyl maleate. In conclusion, the high toxicity and negative impact of metaflumizone and indoxacarb on FAW provided significant implications for the rational utilization of insecticides against this pest.


Asunto(s)
Insecticidas , Larva , Oxazinas , Semicarbazonas , Spodoptera , Animales , Spodoptera/efectos de los fármacos , Spodoptera/crecimiento & desarrollo , Insecticidas/toxicidad , Insecticidas/farmacología , Semicarbazonas/farmacología , Larva/efectos de los fármacos , Oxazinas/toxicidad , Longevidad/efectos de los fármacos , Fertilidad/efectos de los fármacos , Inactivación Metabólica
8.
Zhongguo Zhong Yao Za Zhi ; 49(8): 2076-2087, 2024 Apr.
Artículo en Zh | MEDLINE | ID: mdl-38812224

RESUMEN

Raphani Semen, with both edible and medicinal values, is a typical Chinese herbal medicine with different effects before and after processing. The raw helps ascending and the cooked helps descending. This paper comprehensively summarizes the differences in chemical constituents and pharmacological effects between raw and processed Raphani Semen that are reported in recent years. Based on the principle of quality markers(Q-markers) of traditional Chinese medicines, the chemical constituent sources, chemical constituent detection techniques, and correlation between bidirectional regulatory efficacy and chemical constituents are compared between raw and processed Raphani Semen. The results suggest that sulforaphene and glucoraphanin could be used as candidate Q-markers of raw and processed Raphani Semen, respectively. This review is expected to provide a reference for further research on the processing, new drug development, and improvement of safety and effectiveness of Raphani Semen in clinical application.


Asunto(s)
Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/química , Medicamentos Herbarios Chinos/análisis , Control de Calidad , Humanos , Biomarcadores/análisis
9.
BMC Genomics ; 24(1): 445, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37553577

RESUMEN

BACKGROUND: Single nucleotide polymorphisms (SNPs) and insertions/deletions (InDels) are the most abundant genetic variations and widely distribute across the genomes in plant. Development of SNP and InDel markers is a valuable tool for genetics and genomic research in radish (Raphanus sativus L.). RESULTS: In this study, a total of 366,679 single nucleotide polymorphisms (SNPs) and 97,973 insertion-deletion (InDel) markers were identified based on genome resequencing between 'YZH' and 'XHT'. In all, 53,343 SNPs and 4,257 InDels were detected in two cultivars by transcriptome sequencing. Among the InDel variations, 85 genomic and 15 transcriptomic InDels were newly developed and validated PCR. The 100 polymorphic InDels markers generated 207 alleles among 200 Chinese radish germplasm, with an average 2.07 of the number of alleles (Na) and with an average 0.33 of the polymorphism information content (PIC). Population structure and phylogenetic relationship revealed that the radish cultivars from northern China were clustered together and the southwest China cultivars were clustered together. RNA-Seq analysis revealed that 11,003 differentially expressed genes (DEGs) were identified between the two cultivars, of which 5,020 were upregulated and 5,983 were downregulated. In total, 145 flowering time-related DGEs were detected, most of which were involved in flowering time integrator, circadian clock/photoperiod autonomous, and vernalization pathways. In flowering time-related DGEs region, 150 transcriptomic SNPs and 9 InDels were obtained. CONCLUSIONS: The large amount of SNPs and InDels identified in this study will provide a valuable marker resource for radish genetic and genomic studies. The SNPs and InDels within flowering time-related DGEs provide fundamental insight into for dissecting molecular mechanism of bolting and flowering in radish.


Asunto(s)
Raphanus , Raphanus/genética , Transcriptoma , Polimorfismo de Nucleótido Simple , Filogenia , Análisis de Secuencia de ADN , Genoma de Planta , Mutación INDEL
10.
Clin Immunol ; 256: 109770, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37717672

RESUMEN

The combination of antiangiogenic agents and immune checkpoint inhibitors is more efficient than monotherapy in the management of hepatocellular carcinoma (HCC). Lenvatinib plus anti-PD1 antibodies have become the mainstay in HCC treatment. However, more than half the patients with HCC are non-responsive, and the mechanisms underlying drug resistance are unknown. To address this issue, we performed single-cell sequencing on samples from six HCC patients, aiming to explore cellular signals and molecular pathways related to the effect of lenvatinib plus anti-PD1 antibody treatment. GSVA analysis revealed that treatment with lenvatinib plus anti-PD1 antibody led to an increase in the TNF-NFKB pathway across all immune cell types, as compared to the non-treatment group. Mucosal-associated invariant T (MAIT) cells were found to secrete TNF, which activates TNFRSF1B on regulatory T cells, thereby promoting immunosuppression. Additionally, TNFSF9 was highly expressed in anticancer immune cells, including CD8+ effector T cells, MAIT, and γδ T cells in the treatment group. We also detected CD3+ macrophages in both HCC and pan-cancer tissues. Overall, our findings shed light on the potential mechanisms behind the effectiveness of lenvatinib plus anti-PD1 antibody treatment in HCC patients. By understanding these mechanisms better, we may be able to develop more effective treatment strategies for patients who do not respond to current therapies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Células T Invariantes Asociadas a Mucosa , Humanos , Carcinoma Hepatocelular/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/patología , Células T Invariantes Asociadas a Mucosa/metabolismo , Compuestos de Fenilurea/uso terapéutico , Compuestos de Fenilurea/farmacología , Receptores Tipo II del Factor de Necrosis Tumoral
11.
J Clin Microbiol ; 61(9): e0031623, 2023 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-37671882

RESUMEN

NG-Test CARBA 5 (NG-Biotech) is a rapid in vitro multiplex immunoassay for the phenotypic detection and differentiation of the "big five" carbapenemase families (KPC, OXA-48-like, VIM, IMP, and NDM). Version 2 of this assay was evaluated alongside the Xpert Carba-R assay (Cepheid, Inc.), the modified carbapenem inactivation method (mCIM), and the CIMTris assay, with a collection of carbapenem-resistant non-fermenting Gram-negative bacilli comprising 138 Pseudomonas aeruginosa and 97 Acinetobacter baumannii isolates. Whole-genome sequencing (WGS) was used as the reference standard. For P. aeruginosa, NG-Test CARBA 5 produced an overall percentage agreement (OPA) with WGS of 97.1%, compared with 92.8% forXpert Carba-R and 90.6% for mCIM. For A. baumannii, as OXA-type carbapenemases (non-OXA-48) are not included, both the NG-Test CARBA 5 and Xpert Carba-R only had an OPA of 6.2%, while the CIMTris performed well with an OPA of 99.0%. The majority of A. baumannii isolates (95.9%) tested falsely positive for IMP on NG-Test CARBA 5; no IMP genes were found on WGS. No clear cause was found for this phenomenon; a cross-reacting protein antigen unique to A. baumannii is a possible culprit. NG-Test CARBA 5 performed well for carbapenemase detection in P. aeruginosa. However, results from A. baumannii isolates should be interpreted with caution.


Asunto(s)
Proteínas Bacterianas , beta-Lactamasas , Humanos , Proteínas Bacterianas/genética , beta-Lactamasas/genética , Secuenciación Completa del Genoma , Carbapenémicos/farmacología , Bacterias Gramnegativas/genética , Pseudomonas aeruginosa/genética
12.
J Antimicrob Chemother ; 78(10): 2515-2523, 2023 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-37596905

RESUMEN

OBJECTIVES: The blaZ gene encodes penicillinase, which inactivates penicillin. As there were reports on suboptimal sensitivity for the penicillin zone-edge test, a phenotypic method for blaZ detection, we investigated treatment outcomes in patients with penicillin-susceptible Staphylococcus aureus (PSSA) bacteraemia (phenotypically negative for penicillinase), subjecting isolates to molecular testing for blaZ retrospectively. PATIENTS AND METHODS: A retrospective cohort study was conducted on 121 patients with a first episode of PSSA bacteraemia from 1 January 2012 to 31 October 2015 at Tan Tock Seng Hospital (TTSH), Singapore. Patients were grouped into IV benzylpenicillin and non-benzylpenicillin groups. The primary outcome was overall treatment failure, defined as either 30 day all-cause mortality and/or 90 day relapse. The penicillin (P10) zone-edge test was repeated on archived PSSA isolates, concurrently with penicillin MIC determination via gradient diffusion and PCR for blaZ. RESULTS: Among 121 patients, 57 patients (47.1%) received IV benzylpenicillin as the predominant antibiotic. There was no significant difference in overall treatment failure between treatment with the benzylpenicillin [7/57 (12.3%)] versus non-benzylpenicillin groups [12/64 (18.8%)] (P = 0.33) or cloxacillin/cefazolin [6/37 (16.2%)] (P = 0.59). For 112 PSSA isolates available for testing, repeat penicillin zone-edge testing was negative for penicillinase production, corroborating previous results. A single PSSA isolate with a negative penicillin zone-edge test was found to be positive for blaZ. CONCLUSIONS: We found no differences in overall treatment failure between patients with PSSA bacteraemia treated with benzylpenicillin, anti-staphylococcal ß-lactams cefazolin/cloxacillin and other antimicrobials, when using the penicillin zone-edge test as the phenotypic method for blaZ screening.


Asunto(s)
Bacteriemia , Infecciones Estafilocócicas , Humanos , Antibacterianos/uso terapéutico , Penicilinas/uso terapéutico , Staphylococcus aureus/genética , Estudios Retrospectivos , Cefazolina , Penicilinasa , Penicilina G/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Bacteriemia/tratamiento farmacológico , Resultado del Tratamiento , Cloxacilina , Pruebas de Sensibilidad Microbiana
13.
PLoS Pathog ; 17(3): e1009480, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33784371

RESUMEN

Dengue virus (DENV) causes dengue fever and severe hemorrhagic fever in humans and is primarily transmitted by Aedes aegypti and A. albopictus mosquitoes. The incidence of DENV infection has been gradually increasing in recent years due to global urbanization and international travel. Understanding the virulence determinants in host and vector transmissibility of emerging epidemic DENV will be critical to combat potential outbreaks. The DENV serotype 2 (DENV-2), which caused a widespread outbreak in Taiwan in 2015 (TW2015), is of the Cosmopolitan genotype and is phylogenetically related to the virus strain linked to another large outbreak in Indonesia in 2015. We found that the TW2015 virus was highly virulent in type I and type II interferon-deficient mice, with robust replication in spleen, lung, and intestine. The TW2015 virus also had high transmissibility to Aedes mosquitoes and could be effectively spread in a continuous mosquitoes-mouse-mosquitoes-mouse transmission cycle. By making 16681-based mutants carrying different segments of the TW2015 virus, we identified the structural pre-membrane (prM) and envelope (E) genes as key virulence determinants in the host, with involvement in the high transmissibility of the TW2015 virus in mosquitoes. The transmission mouse model will make a useful platform for evaluation of DENV with high epidemic potential and development of new strategies against dengue outbreaks.


Asunto(s)
Culicidae/virología , Virus del Dengue/genética , Virus del Dengue/patogenicidad , Dengue/virología , Insectos Vectores/virología , Virulencia/fisiología , Animales , Modelos Animales de Enfermedad , Genotipo , Ratones
14.
New Phytol ; 238(2): 598-611, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36651117

RESUMEN

Decomposition and fire are major carbon pathways in many ecosystems, yet potential linkages between these processes are poorly understood. We test whether variability in decomposability and flammability across species are related to each other and to key plant functional traits in tropical swamp forests, where habitat degradation is elevating decomposition and fire regimes. Using senesced and fresh leaves of 22 swamp tree species in Singapore, we conducted an in situ decomposition experiment and a laboratory flammability experiment. We analysed 16 leaf physical and biochemical traits as predictors of decomposability and components of flammability: combustibility, ignitability and sustainability. Decomposability and flammability were largely decoupled across species, despite some shared predictive traits such as specific leaf area (SLA). Physical traits predicted that thicker leaves with a smaller SLA and volume decomposed faster, while various cation concentrations predicted flammability components, particularly ignitability. We show that flammability and decomposability of swamp forest leaves are decoupled because flammability is mostly driven by biochemical traits, while decomposition is driven by physical traits. Our approach identifies species that are slow to decompose and burn (e.g. Calophyllum tetrapterum and Xanthophyllum flavescens), which could be planted to mitigate carbon losses in tropical swamp reforestation.


Asunto(s)
Ecosistema , Humedales , Bosques , Árboles/metabolismo , Plantas , Hojas de la Planta/metabolismo , Carbono/metabolismo
15.
Theor Appl Genet ; 137(1): 4, 2023 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-38085292

RESUMEN

KEY MESSAGE: Two major QTLs for bolting time in radish were mapped to chromosome 02 and 07 in a 0.37 Mb and 0. 52 Mb interval, RsFLC1 and RsFLC2 is the critical genes. Radish (Raphanus sativus L.) is an important vegetable crop of Cruciferae. The premature bolting and flowering reduces the yield and quality of the fleshy root of radish. However, the molecular mechanism underlying bolting and flowering in radish remains unknown. In YZH (early bolting) × XHT (late bolting) F2 population, a high-density genetic linkage map was constructed with genetic distance of 2497.74 cM and an average interval of 2.31 cM. A total of nine QTLs for bolting time and two QTLs for flowering time were detected. Three QTLs associated with bolting time in radish were identified by QTL-seq using radish GDE (early bolting) × GDL (late bolting) F2 population. Fine mapping narrowed down qBT2 and qBT7.2 to an 0.37 Mb and 0.52 Mb region on chromosome 02 and 07, respectively. RNA-seq and qRT-PCR analysis showed that RsFLC1 and RsFLC2 were the candidate gene for qBT7.2 and qBT2 locus, respectively. Subcellular localization exhibited that RsFLC1 and RsFLC2 were mainly expressed in the nucleus. A 1856-bp insertion in the first intron of RsFLC1 was responsible for bolting time. Overexpression of RsFLC2 in Arabidopsis was significantly delayed flowering. These findings will provide new insights into the exploring the molecular mechanism of late bolting and promote the marker-assisted selection for breeding late-bolting varieties in radish.


Asunto(s)
Arabidopsis , Raphanus , Raphanus/genética , Mapeo Cromosómico , Fitomejoramiento , Sitios de Carácter Cuantitativo , Arabidopsis/genética
16.
Glycoconj J ; 40(5): 551-563, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37606864

RESUMEN

Globo A is a neutral Globo-series glycosphingolipid (GSL) that shows natural properties of a cytotoxicity receptor NKp44 binding ligand. The highly complex heptasaccharide glycan structure of Globo A combined with its biological profile provides a unique target for the development of a synthetic method to facilitate its bioactivity studies. Here, a concise chemoenzymatic route to the synthesis of Globo A and its α1,3-galactose-linked congener Globo B is reported. The key to success was the use of a synthetic azido ß-Globo H sphingosine (Globo H-ßSph) as an acceptor substrate and two glycosyl transferases, an α1,3-N-acetylgalactosaminyltransferase from Helicobacter mustelae (BgtA) and a human blood group B α1,3-galactosyltransferase (h1,3GTB), for stereoselective construction of the terminal α1,3-GalNAc and α1,3-Gal linkages, respectively. The azido-Sph lipid sidechain is further elaborated by reduction and a chemoselective N-acylation to complete the total synthesis of the neutral Globo-series GSLs. In addition, the synthesis of Forssman and para-Forssman antigens were prepared. The strategy may be suitable for accessing other complex GSLs and related lipid-modified GSL derivatives.


Asunto(s)
Glicoesfingolípidos , Glicoesfingolípidos Neutros , Humanos , Glicoesfingolípidos/metabolismo , Unión Proteica
17.
J Biomed Sci ; 30(1): 96, 2023 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-38110940

RESUMEN

BACKGROUND: Human enteroviruses A71 (EV-A71) and D68 (EV-D68) are the suspected causative agents of hand-foot-and-mouth disease, aseptic meningitis, encephalitis, acute flaccid myelitis, and acute flaccid paralysis in children. Until now, no cure nor mucosal vaccine existed for EV-A71 and EV-D68. Novel mucosal bivalent vaccines are highly important for preventing EV-A71 and EV-D68 infections. METHODS: In this study, formalin-inactivated EV-A71 and EV-D68 were used as antigens, while PS-G, a polysaccharide from Ganoderma lucidum, was used as an adjuvant. Natural polysaccharides have the characteristics of intrinsic immunomodulation, biocompatibility, low toxicity, and safety. Mice were immunized intranasally with PBS, EV-A71, EV-D68, or EV-A71 + EV-D68, with or without PS-G as an adjuvant. RESULTS: The EV-A71 + EV-D68 bivalent vaccine generated considerable EV-A71- and EV-D68-specific IgG and IgA titres in the sera, nasal washes, saliva, bronchoalveolar lavage fluid, and feces. These antibodies neutralized EV-D68 and EV-A71 infectivity. They also cross-neutralized infections by different EV-D68 and EV-A71 sub-genotypes. Furthermore, compared with the PBS group, EV-A71 + EV-D68 + PS-G-vaccinated mice exhibited an increased number of EV-D68- and EV-A71-specific IgA- and IgG-producing cells. In addition, T-cell proliferative responses, and IFN-γ and IL-17 secretion in the spleen were substantially induced when PS-G was used as an adjuvant with EV-A71 + EV-D68. Finally, in vivo challenge experiments demonstrated that the immune sera induced by EV-A71 + EV-D68 + PS-G conferred protection in neonate mice against lethal EV-A71 and EV-D68 challenges as indicated by the increased survival rate and decreased clinical score and viral RNA tissue expression. Taken together, all EV-A71/EV-D68 + PS-G-immunized mice developed potent specific humoral, mucosal, and cellular immune responses to EV-D68 and EV-A71 and were protected against them. CONCLUSIONS: These findings demonstrated that PS-G can be used as a potential adjuvant for EV-A71 and EV-D68 bivalent mucosal vaccines. Our results provide useful information for the further preclinical and clinical development of a mucosal bivalent enterovirus vaccine against both EV-A71 and EV-D68 infections.


Asunto(s)
Enterovirus Humano A , Enterovirus Humano D , Infecciones por Enterovirus , Enterovirus , Reishi , Niño , Animales , Humanos , Ratones , Enterovirus Humano D/genética , Enterovirus Humano A/genética , Vacunas Combinadas , Antígenos Virales , Inmunoglobulina A , Inmunoglobulina G
18.
Immunity ; 40(4): 477-89, 2014 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-24745332

RESUMEN

We identified three retinoid-related orphan receptor gamma t (RORγt)-specific inhibitors that suppress T helper 17 (Th17) cell responses, including Th17-cell-mediated autoimmune disease. We systemically characterized RORγt binding in the presence and absence of drugs with corresponding whole-genome transcriptome sequencing. RORγt acts as a direct activator of Th17 cell signature genes and a direct repressor of signature genes from other T cell lineages; its strongest transcriptional effects are on cis-regulatory sites containing the RORα binding motif. RORγt is central in a densely interconnected regulatory network that shapes the balance of T cell differentiation. Here, the three inhibitors modulated the RORγt-dependent transcriptional network to varying extents and through distinct mechanisms. Whereas one inhibitor displaced RORγt from its target loci, the other two inhibitors affected transcription predominantly without removing DNA binding. Our work illustrates the power of a system-scale analysis of transcriptional regulation to characterize potential therapeutic compounds that inhibit pathogenic Th17 cells and suppress autoimmunity.


Asunto(s)
Bencenoacetamidas/farmacología , Compuestos de Bencidrilo/farmacología , Digoxina/farmacología , Encefalomielitis Autoinmune Experimental/tratamiento farmacológico , Redes Reguladoras de Genes/efectos de los fármacos , Compuestos Heterocíclicos de 4 o más Anillos/farmacología , Esclerosis Múltiple/tratamiento farmacológico , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/antagonistas & inhibidores , Subgrupos de Linfocitos T/efectos de los fármacos , Células Th17/efectos de los fármacos , Androstenoles/química , Animales , Bencenoacetamidas/química , Compuestos de Bencidrilo/química , Diferenciación Celular/efectos de los fármacos , Línea Celular Tumoral , Linaje de la Célula/efectos de los fármacos , Citocinas/metabolismo , Digoxina/química , Encefalomielitis Autoinmune Experimental/inmunología , Compuestos Heterocíclicos de 4 o más Anillos/química , Humanos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Esclerosis Múltiple/inmunología , Glicoproteína Mielina-Oligodendrócito/inmunología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Fragmentos de Péptidos/inmunología , Unión Proteica/efectos de los fármacos , Relación Estructura-Actividad , Biología de Sistemas , Subgrupos de Linfocitos T/inmunología , Células Th17/inmunología , Transcripción Genética/efectos de los fármacos , Activación Transcripcional/efectos de los fármacos
19.
BMC Infect Dis ; 23(1): 371, 2023 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-37264307

RESUMEN

BACKGROUND: Dengue, Chikungunya, and Zika are co-endemic in Honduras and are often misdiagnosed due to similar clinical and epidemiological behavior. Most arboviral infections reported in primary care are based on clinical diagnoses without laboratory confirmation. Therefore, the accuracy of physicians' diagnoses and the factors that affect them needs to be evaluated. METHODS: A cross-sectional study with convenience sampling at primary healthcare centers was conducted from June to September 2016 and 2017. Clinical data and dried blood spots on Whatman 903 filter paper from 415 arboviral cases and 248 non-arboviral febrile cases were collected. Viral RNA was extracted from a 6-mm DBS paper disc and confirmed by RT-qPCR and sequencing. RESULTS: Only 30.84% of diagnostic accuracy was observed in physicians in primary care when comparing arboviral clinical diagnosis with RT-qPCR detection. Moreover, in Dengue and Zika clinical cases, only 8.23% and 27.08% were RT-qPCR confirmed, respectively. No Chikungunya cases were confirmed. In 2017, 20.96% of febrile cases were RT-qPCR confirmed arboviral infections. The symptoms of 45.5% of arboviral cases can fit more than one case definition for arboviruses. The "symptom compliance" and "patient with suspected close contact" were the criteria most utilized by physicians for arboviral diagnosis. The pattern of the epidemiological curves of the arboviral clinical cases didn't match the one of the RT-qPCR confirmed cases. CONCLUSIONS: Low diagnostic accuracy for overall and individual arboviral infections was observed in physicians. Unspecific symptomatology, overlapping case definitions, and reported close contact to an arboviral patient might contribute to misdiagnosis. Without laboratory confirmation, surveillance data may not reflect the real behavior of these diseases and could impact health interventions.


Asunto(s)
Infecciones por Arbovirus , Arbovirus , Fiebre Chikungunya , Dengue , Infección por el Virus Zika , Virus Zika , Humanos , Dengue/diagnóstico , Dengue/epidemiología , Honduras/epidemiología , Estudios Transversales , Infección por el Virus Zika/diagnóstico , Infección por el Virus Zika/epidemiología , Fiebre Chikungunya/diagnóstico , Fiebre Chikungunya/epidemiología , Virus Zika/genética , Infecciones por Arbovirus/epidemiología , Fiebre/etiología , Atención Primaria de Salud
20.
Epidemiol Infect ; 151: e155, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37675569

RESUMEN

Longitudinal studies on the variations of phenotypic and genotypic characteristics of K. pneumoniae across two decades are rare. We aimed to determine the antimicrobial susceptibility and virulence factors for K. pneumoniae isolated from patients with bacteraemia or urinary tract infection (UTI) from 1999 to 2022. A total of 699 and 1,267 K. pneumoniae isolates were isolated from bacteraemia and UTI patients, respectively, and their susceptibility to twenty antibiotics was determined; PCR was used to identify capsular serotypes and virulence-associated genes. K64 and K1 serotypes were most frequently observed in UTI and bacteraemia, respectively, with an increasing frequency of K20, K47, and K64 observed in recent years. entB and wabG predominated across all isolates and serotypes; the least frequent virulence gene was htrA. Most isolates were susceptible to carbapenems, amikacin, tigecycline, and colistin, with the exception of K20, K47, and K64 where resistance was widespread. The highest average number of virulence genes was observed in K1, followed by K2, K20, and K5 isolates, which suggest their contribution to the high virulence of K1. In conclusion, we found that the distribution of antimicrobial susceptibility, virulence gene profiles, and capsular types of K. pneumoniae over two decades were associated with their clinical source.


Asunto(s)
Bacteriemia , Infecciones Urinarias , Humanos , Virulencia/genética , Klebsiella pneumoniae/genética , Estudios Longitudinales , Serogrupo , Infecciones Urinarias/epidemiología , Bacteriemia/epidemiología , Farmacorresistencia Microbiana , Antibacterianos/farmacología
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