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1.
Cell ; 184(8): 2229-2238.e13, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33691138

RESUMEN

The biosafety level 3 (BSL-3) requirement to culture severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a bottleneck for research. Here, we report a trans-complementation system that produces single-round infectious SARS-CoV-2 that recapitulates authentic viral replication. We demonstrate that the single-round infectious SARS-CoV-2 can be used at BSL-2 laboratories for high-throughput neutralization and antiviral testing. The trans-complementation system consists of two components: a genomic viral RNA containing ORF3 and envelope gene deletions, as well as mutated transcriptional regulator sequences, and a producer cell line expressing the two deleted genes. Trans-complementation of the two components generates virions that can infect naive cells for only one round but does not produce wild-type SARS-CoV-2. Hamsters and K18-hACE2 transgenic mice inoculated with the complementation-derived virions exhibited no detectable disease, even after intracranial inoculation with the highest possible dose. Thus, the trans-complementation platform can be safely used at BSL-2 laboratories for research and countermeasure development.


Asunto(s)
COVID-19/virología , Contención de Riesgos Biológicos/métodos , SARS-CoV-2 , Células A549 , Animales , Chlorocebus aethiops , Cricetinae , Prueba de Complementación Genética/métodos , Genoma Viral , Células HEK293 , Humanos , Masculino , Ratones , Ratones Transgénicos , ARN Viral , SARS-CoV-2/genética , SARS-CoV-2/patogenicidad , SARS-CoV-2/fisiología , Células Vero , Virulencia , Replicación Viral
2.
Nature ; 602(7896): 294-299, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34818667

RESUMEN

The B.1.1.7 variant (also known as Alpha) of SARS-CoV-2, the cause of the COVID-19 pandemic, emerged in the UK in the summer of 2020. The prevalence of this variant increased rapidly owing to an increase in infection and/or transmission efficiency1. The Alpha variant contains 19 nonsynonymous mutations across its viral genome, including 8 substitutions or deletions in the spike protein that interacts with cellular receptors to mediate infection and tropism. Here, using a reverse genetics approach, we show that of the 8 individual spike protein substitutions, only N501Y resulted in consistent fitness gains for replication in the upper airway in a hamster model as well as in primary human airway epithelial cells. The N501Y substitution recapitulated the enhanced viral transmission phenotype of the eight mutations in the Alpha spike protein, suggesting that it is a major determinant of the increased transmission of the Alpha variant. Mechanistically, the N501Y substitution increased the affinity of the viral spike protein for cellular receptors. As suggested by its convergent evolution in Brazil, South Africa and elsewhere2,3, our results indicate that N501Y substitution is an adaptive spike mutation of major concern.


Asunto(s)
Sustitución de Aminoácidos , COVID-19/transmisión , COVID-19/virología , SARS-CoV-2/patogenicidad , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/metabolismo , Enzima Convertidora de Angiotensina 2/metabolismo , Animales , Unión Competitiva , Bronquios/citología , Células Cultivadas , Cricetinae , Humanos , Masculino , Mesocricetus , Modelos Moleculares , Mutación , Unión Proteica , SARS-CoV-2/química , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/genética , Replicación Viral
3.
Nature ; 602(7897): 475-480, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34929721

RESUMEN

Alphaviruses, like many other arthropod-borne viruses, infect vertebrate species and insect vectors separated by hundreds of millions of years of evolutionary history. Entry into evolutionarily divergent host cells can be accomplished by recognition of different cellular receptors in different species, or by binding to receptors that are highly conserved across species. Although multiple alphavirus receptors have been described1-3, most are not shared among vertebrate and invertebrate hosts. Here we identify the very low-density lipoprotein receptor (VLDLR) as a receptor for the prototypic alphavirus Semliki forest virus. We show that the E2 and E1 glycoproteins (E2-E1) of Semliki forest virus, eastern equine encephalitis virus and Sindbis virus interact with the ligand-binding domains (LBDs) of VLDLR and apolipoprotein E receptor 2 (ApoER2), two closely related receptors. Ectopic expression of either protein facilitates cellular attachment, and internalization of virus-like particles, a VLDLR LBD-Fc fusion protein or a ligand-binding antagonist block Semliki forest virus E2-E1-mediated infection of human and mouse neurons in culture. The administration of a VLDLR LBD-Fc fusion protein has protective activity against rapidly fatal Semliki forest virus infection in mouse neonates. We further show that invertebrate receptor orthologues from mosquitoes and worms can serve as functional alphavirus receptors. We propose that the ability of some alphaviruses to infect a wide range of hosts is a result of their engagement of evolutionarily conserved lipoprotein receptors and contributes to their pathogenesis.


Asunto(s)
Mosquitos Vectores , Virus de los Bosques Semliki , Animales , Proteínas Relacionadas con Receptor de LDL , Ligandos , Ratones , Receptores de LDL , Virus de los Bosques Semliki/metabolismo , Virus Sindbis/fisiología
4.
Nature ; 596(7871): 273-275, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34111888

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is continuing to evolve around the world, generating new variants that are of concern on the basis of their potential for altered transmissibility, pathogenicity, and coverage by vaccines and therapeutic agents1-5. Here we show that serum samples taken from twenty human volunteers, two or four weeks after their second dose of the BNT162b2 vaccine, neutralize engineered SARS-CoV-2 with a USA-WA1/2020 genetic background (a virus strain isolated in January 2020) and spike glycoproteins from the recently identified B.1.617.1, B.1.617.2, B.1.618 (all of which were first identified in India) or B.1.525 (first identified in Nigeria) lineages. Geometric mean plaque reduction neutralization titres against the variant viruses-particularly the B.1.617.1 variant-seemed to be lower than the titre against the USA-WA1/2020 virus, but all sera tested neutralized the variant viruses at titres of at least 1:40. The susceptibility of the variant strains to neutralization elicited by the BNT162b2 vaccine supports mass immunization as a central strategy to end the coronavirus disease 2019 (COVID-19) pandemic globally.


Asunto(s)
Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Vacunas contra la COVID-19/inmunología , COVID-19/inmunología , COVID-19/virología , Pruebas de Neutralización , SARS-CoV-2/inmunología , Animales , Anticuerpos Neutralizantes/sangre , Anticuerpos Antivirales/sangre , Vacuna BNT162 , COVID-19/prevención & control , Vacunas contra la COVID-19/genética , Chlorocebus aethiops , Humanos , SARS-CoV-2/genética , Glicoproteína de la Espiga del Coronavirus/química , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Sintéticas/genética , Células Vero , Vacunas de ARNm
5.
Nature ; 592(7852): 116-121, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33106671

RESUMEN

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike protein substitution D614G became dominant during the coronavirus disease 2019 (COVID-19) pandemic1,2. However, the effect of this variant on viral spread and vaccine efficacy remains to be defined. Here we engineered the spike D614G substitution in the USA-WA1/2020 SARS-CoV-2 strain, and found that it enhances viral replication in human lung epithelial cells and primary human airway tissues by increasing the infectivity and stability of virions. Hamsters infected with SARS-CoV-2 expressing spike(D614G) (G614 virus) produced higher infectious titres in nasal washes and the trachea, but not in the lungs, supporting clinical evidence showing that the mutation enhances viral loads in the upper respiratory tract of COVID-19 patients and may increase transmission. Sera from hamsters infected with D614 virus exhibit modestly higher neutralization titres against G614 virus than against D614 virus, suggesting that the mutation is unlikely to reduce the ability of vaccines in clinical trials to protect against COVID-19, and that therapeutic antibodies should be tested against the circulating G614 virus. Together with clinical findings, our work underscores the importance of this variant in viral spread and its implications for vaccine efficacy and antibody therapy.


Asunto(s)
COVID-19/transmisión , COVID-19/virología , Aptitud Genética , Mutación , SARS-CoV-2/genética , SARS-CoV-2/fisiología , Glicoproteína de la Espiga del Coronavirus/genética , Animales , Anticuerpos Neutralizantes/inmunología , Anticuerpos Neutralizantes/uso terapéutico , COVID-19/inmunología , Vacunas contra la COVID-19/inmunología , Cricetinae , Modelos Animales de Enfermedad , Humanos , Pulmón/virología , Masculino , Mesocricetus/virología , Modelos Biológicos , Mucosa Nasal/virología , Pruebas de Neutralización , Estabilidad Proteica , SARS-CoV-2/inmunología , SARS-CoV-2/patogenicidad , Técnicas de Cultivo de Tejidos , Tráquea/virología , Carga Viral , Virión/química , Virión/patogenicidad , Virión/fisiología , Replicación Viral/genética
6.
EMBO J ; 40(19): e107974, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34459501

RESUMEN

Identification of the driving force behind malignant transformation holds the promise to combat the relapse and therapeutic resistance of cancer. We report here that the single nucleotide polymorphism (SNP) rs4971059, one of 65 new breast cancer risk loci identified in a recent genome-wide association study (GWAS), functions as an active enhancer of TRIM46 expression. Recreating the G-to-A polymorphic switch caused by the SNP via CRISPR/Cas9-mediated homologous recombination leads to an overt upregulation of TRIM46. We find that TRIM46 is a ubiquitin ligase that targets histone deacetylase HDAC1 for ubiquitination and degradation and that the TRIM46-HDAC1 axis regulates a panel of genes, including ones critically involved in DNA replication and repair. Consequently, TRIM46 promotes breast cancer cell proliferation and chemoresistance in vitro and accelerates tumor growth in vivo. Moreover, TRIM46 is frequently overexpressed in breast carcinomas, and its expression is correlated with lower HDAC1 expression, higher histological grades, and worse prognosis of the patients. Together, our study links SNP rs4971059 to replication and to breast carcinogenesis and chemoresistance and support the pursuit of TRIM46 as a potential target for breast cancer intervention.


Asunto(s)
Alelos , Transformación Celular Neoplásica/genética , Transformación Celular Neoplásica/metabolismo , Resistencia a Antineoplásicos/genética , Histona Desacetilasa 1/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Polimorfismo de Nucleótido Simple , Línea Celular Tumoral , Proliferación Celular/genética , Reparación del ADN , Replicación del ADN , Elementos de Facilitación Genéticos , Femenino , Humanos , Intrones , Proteínas del Tejido Nervioso/genética , Unión Proteica , Proteolisis , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación
7.
Biochem Biophys Res Commun ; 691: 149314, 2024 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-38039831

RESUMEN

P: -glycoprotein (P-gp/ABCB1) overexpression is one of the primary causes of multidrug resistance (MDR). Therefore, it is crucial to discover effective pharmaceuticals to combat multidrug resistance mediated by ABCB1. Pemigatinib is a selective the fibroblast growth factor receptor (FGFR) inhibitor that is used to treat a variety of solid tumors, Clinical Trials for Urothelial Carcinoma (NCT02872714) completed its research on Pemigatinib. This study aimed to determine whether Pemigatinib can reverse ABCB1-mediated multidrug resistance, as well as its mechanism of action. Pemigatinib substantially reversed ABCB1-mediated multidrug resistance, as determined by a CCK8 assay, and immunofluorescence experiments revealed that Pemigatinib had no effect on the intracellular localization of ABCB1. Pemigatinib was discovered to increase intracellular drug accumulation, thereby reversing multidrug resistance. In addition, Docking analysis revealed that Pemigatinib and ABCB1 have a high affinity for one another. This study concludes that Pemigatinib is capable of reversing the multidrug resistance mediated by ABCB1, offering ideas and references for the clinical application of Pemigatinib.


Asunto(s)
Antineoplásicos , Carcinoma de Células Transicionales , Neoplasias de la Vejiga Urinaria , Humanos , Antineoplásicos/farmacología , Antineoplásicos/metabolismo , Resistencia a Antineoplásicos , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos , Subfamilia B de Transportador de Casetes de Unión a ATP
8.
J Pharmacol Exp Ther ; 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849142

RESUMEN

Acute Kidney Injury (AKI) is characterized by an abrupt decline in kidney function and has been associated with excess risks of death, kidney disease progression, and cardiovascular events. The kidney has a high energetic demand with mitochondrial health being essential to renal function and damaged mitochondria has been reported across AKI subtypes. 5' adenosine monophosphate-activated protein kinase (AMPK) activation preserves cellular energetics through improvement of mitochondrial function and biogenesis when ATP levels are low such as under ischemia-induced AKI. We developed a selective potent small molecule pan AMPK activator, compound 1, and tested its ability to increase AMPK activity and preserve kidney function during ischemia/reperfusion injury in rats. A single administration of 1 caused sustained activation of AMPK for at least 24 hours, protected against acute tubular necrosis, and reduced clinical markers of tubular injury such as NephroCheck and Fractional Excretion of Sodium (FENa). Reduction in plasma creatinine and increased Glomerular Filtration Rate (GFR) indicated preservation of kidney function. Surprisingly, we observed a strong diuretic effect of AMPK activation associated with natriuresis both with and without AKI. Our findings demonstrate that activation of AMPK leads to protection of tubular function under hypoxic/ischemic conditions which holds promise as a potential novel therapeutic approach for AKI. Significance Statement No approved pharmacological therapies currently exist for acute kidney injury. We developed Compound 1 which dose-dependently activated AMPK in the kidney and protected kidney function and tubules after ischemic renal injury in the rat. This was accompanied by natriuresis in injured as well as uninjured rats.

9.
Blood ; 140(8): 861-874, 2022 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-35427421

RESUMEN

Target identification for chimeric antigen receptor (CAR) T-cell therapies remains challenging due to the limited repertoire of tumor-specific surface proteins. Intracellular proteins presented in the context of cell surface HLA provide a wide pool of potential antigens targetable through T-cell receptor mimic antibodies. Mass spectrometry (MS) of HLA ligands from 8 hematologic and nonhematologic cancer cell lines identified a shared, non-immunogenic, HLA-A*02-restricted ligand (ALNEQIARL) derived from the kinetochore-associated NDC80 gene. CAR T cells directed against the ALNEQIARL:HLA-A*02 complex exhibited high sensitivity and specificity for recognition and killing of multiple cancer types, especially those of hematologic origin, and were efficacious in mouse models against a human leukemia and a solid tumor. In contrast, no toxicities toward resting or activated healthy leukocytes as well as hematopoietic stem cells were observed. This shows how MS can inform the design of broadly reactive therapeutic T-cell receptor mimic CAR T-cell therapies that can target multiple cancer types currently not druggable by small molecules, conventional CAR T cells, T cells, or antibodies.


Asunto(s)
Neoplasias Hematológicas , Neoplasias , Animales , Anticuerpos/metabolismo , Proteínas del Citoesqueleto/metabolismo , Antígenos HLA-A , Neoplasias Hematológicas/metabolismo , Neoplasias Hematológicas/terapia , Humanos , Inmunoterapia Adoptiva/métodos , Ratones , Receptores de Antígenos de Linfocitos T , Linfocitos T
10.
BMC Cancer ; 24(1): 497, 2024 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-38637730

RESUMEN

This study aims to investigate the role and mechanism of tubiquitin-conjugating enzyme E2 C (UBE2C) in acute myeloid leukemia (AML). Initially, UBE2C expression in leukemia was analyzed using the Cancer Genome Atlas database. Further, we silenced UBE2C expression using small-hairpin RNA (sh-RNA). UBE2C expression was detected via the quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and Western blot analysis. Apoptotic events and reactive oxygen species (ROS) levels were detected by flow cytometry. A xenograft model of leukemia cells were established, and the protein levels of UBE2C, KI-67, and cleaved-caspase 3 were detected by immunohistochemistry. We reported an overexpression of UBE2C in leukemia patients and cell lines (HL60, THP-1, U937, and KG-1 cells). Moreover, a high expression level of UBE2C was correlated with a dismal prognosis in AML patients. UBE2C knockdown inhibited the viability and promoted apoptosis in AML cells by regulating the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) signaling pathway. Furthermore, UBE2C knockdown increased cellular Fe2+ and ROS levels, and enhanced erastin-induced ferroptosis in a proteasome-dependent manner. UBE2C knockdown also suppressed the tumor formation of AML cells in the mouse model. In summary, our findings suggest that UBE2C overexpression promotes the proliferation and inhibits ferroptosis in AML cells by activating the PI3K/AKT pathway.


Asunto(s)
Leucemia Mieloide Aguda , Proteínas Proto-Oncogénicas c-akt , Animales , Humanos , Ratones , Apoptosis/genética , Línea Celular Tumoral , Proliferación Celular/genética , Leucemia Mieloide Aguda/patología , Fosfatidilinositol 3-Quinasa , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Especies Reactivas de Oxígeno , ARN Interferente Pequeño , Enzimas Ubiquitina-Conjugadoras/genética
11.
BMC Neurol ; 24(1): 154, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38714961

RESUMEN

BACKGROUND: Fragile X-associated tremor/ataxia syndrome (FXTAS) is a neurodegenerative disorder caused by CGG repeat expansion of FMR1 gene. Both FXTAS and neuronal intranuclear inclusion disease (NIID) belong to polyglycine diseases and present similar clinical, radiological, and pathological features, making it difficult to distinguish these diseases. Reversible encephalitis-like attacks are often observed in NIID. It is unclear whether they are presented in FXTAS and can be used for differential diagnosis of NIID and FXTAS. CASE PRESENTATION: A 63-year-old Chinese male with late-onset gait disturbance, cognitive decline, and reversible attacks of fever, consciousness impairment, dizziness, vomiting, and urinary incontinence underwent neurological assessment and examinations, including laboratory tests, electroencephalogram test, imaging, skin biopsy, and genetic test. Brain MRI showed T2 hyperintensities in middle cerebellar peduncle and cerebrum, in addition to cerebellar atrophy and DWI hyperintensities along the corticomedullary junction. Lesions in the brainstem were observed. Skin biopsy showed p62-positive intranuclear inclusions. The possibilities of hypoglycemia, lactic acidosis, epileptic seizures, and cerebrovascular attacks were excluded. Genetic analysis revealed CGG repeat expansion in FMR1 gene, and the number of repeats was 111. The patient was finally diagnosed as FXTAS. He received supportive treatment as well as symptomatic treatment during hospitalization. His encephalitic symptoms were completely relieved within one week. CONCLUSIONS: This is a detailed report of a case of FXTAS with reversible encephalitis-like episodes. This report provides new information for the possible and rare features of FXTAS, highlighting that encephalitis-like episodes are common in polyglycine diseases and unable to be used for differential diagnosis.


Asunto(s)
Ataxia , Encefalitis , Síndrome del Cromosoma X Frágil , Temblor , Humanos , Ataxia/diagnóstico , Ataxia/genética , Diagnóstico Diferencial , Encefalitis/diagnóstico , Encefalitis/complicaciones , Encefalitis/genética , Encefalitis/patología , Proteína de la Discapacidad Intelectual del Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/genética , Síndrome del Cromosoma X Frágil/diagnóstico , Síndrome del Cromosoma X Frágil/complicaciones , Cuerpos de Inclusión Intranucleares/patología , Enfermedades Neurodegenerativas/diagnóstico , Enfermedades Neurodegenerativas/genética , Enfermedades Neurodegenerativas/complicaciones , Temblor/diagnóstico , Temblor/genética , Temblor/etiología
12.
BMC Med ; 21(1): 388, 2023 10 09.
Artículo en Inglés | MEDLINE | ID: mdl-37814306

RESUMEN

BACKGROUND: Dipeptidyl peptidase-4 inhibitors (DPP-4i) have become firmly established in treatment algorithms and national guidelines for improving glycemic control in type 2 diabetes mellitus (T2DM).To report the findings from a multicenter, randomized, double-blind, placebo-controlled phase 3 clinical trial, which was designed to assess the efficacy and safety of a novel DPP-4 inhibitor fotagliptin in treatment-naive patients with T2DM. METHODS: Patients with T2DM were randomized to receive fotagliptin (n = 230), alogliptin (n = 113) or placebo (n = 115) at a 2:1:1 ratio for 24 weeks of double-blind treatment period, followed by an open-label treatment period, making up a total of 52 weeks. The primary efficacy endpoint was to determine the superiority of fotagliptin over placebo in the change of HbA1c from baseline to Week 24. All serious or significant adverse events were recorded. RESULTS: After 24 weeks, mean decreases in HbA1c from baseline were -0.70% for fotagliptin, -0.72% for alogliptin and -0.26% for placebo. Estimated mean treatment differences in HbA1c were -0.44% (95% confidence interval [CI]: -0.62% to -0.27%) for fotagliptin versus placebo, and -0.46% (95% CI: -0.67% to -0.26%) for alogliptin versus placebo, and 0.02% (95%CI: -0.16% to 0.19%; upper limit of 95%CI < margin of 0.4%) for fotagliptin versus alogliptin. So fotagliptin was non-inferior to alogliptin. Compared with subjects with placebo (15.5%), significantly more patients with fotagliptin (37.0%) and alogliptin (35.5%) achieved HbA1c < 7.0% after 24 weeks of treatment. During the whole 52 weeks of treatment, the overall incidence of hypoglycemia was low for both of the fotagliptin and alogliptin groups (1.0% each). No drug-related serious adverse events were observed in any treatment group. CONCLUSIONS: In summary, the study demonstrated improvement in glycemic control and a favorable safety profile for fotagliptin in treatment-naive patients with T2DM. TRIAL REGISTRATION: ClinicalTrail.gov NCT05782192.


Asunto(s)
Diabetes Mellitus Tipo 2 , Inhibidores de la Dipeptidil-Peptidasa IV , Humanos , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hemoglobina Glucada , Glucemia , Hipoglucemiantes/efectos adversos , Inhibidores de la Dipeptidil-Peptidasa IV/efectos adversos , Método Doble Ciego , Resultado del Tratamiento
13.
Int J Syst Evol Microbiol ; 73(12)2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38117210

RESUMEN

Two bacterial strains, FP1935T and FP1962, were isolated from the rhizosphere soil of cucumber and Chieh-qua plants, respectively, in Jilin Province, PR China. These strains were Gram-stain-negative, aerobic, rod-shaped and motile with one or two polar flagella. Analysis of the 16S rRNA gene sequences revealed that they represented members of the genus Pseudomonas, with the highest similarity to Pseudomonas silesiensis A3T (99.45 %), Pseudomonas frederiksbergensis JAJ28T (99.45 %), Pseudomonas mandelii NBRC 103147T (99.38 %), Pseudomonas piscium P50T (99.27 %) and Pseudomonas meliae CFBP 3225T (99.18 %). The DNA G+C contents of FP1935T and FP1962 were 58.99 mol% and 58.98 mol%, respectively. The results of in silico genome-based analyses indicated that these strains were distinct from other species in the genus Pseudomonas, as the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values were below the recommended thresholds of 95 % (ANI) and 70 % (dDDH) for prokaryotic species delineation, with no values exceeding 94.1 and 55.8 %, respectively, compared with any other related species. The results of phenotypic and chemotaxonomic tests confirmed their differentiation from their closest relatives. The fatty acid profiles of both strains mainly consisted of summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0 and C16 : 0. The predominant respiratory quinone was Q-9. Polar lipids include phosphatidylethanolamine, unidentified aminophospholipids, unidentified lipids and an unidentified phospholipid. On the basis of these phenotypic and genotypic results, we propose the name Pseudomonas cucumis sp. nov. for these novel strains. The type strain is FP1935T (=ACCC 62445T=JCM 35690T).


Asunto(s)
Cucumis , ARN Ribosómico 16S/genética , Rizosfera , Composición de Base , Ácidos Grasos/química , Filogenia , Análisis de Secuencia de ADN , ADN Bacteriano/genética , Técnicas de Tipificación Bacteriana
14.
Nature ; 545(7655): 482-486, 2017 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-28514450

RESUMEN

Zika virus (ZIKV) remained obscure until the recent explosive outbreaks in French Polynesia (2013-2014) and South America (2015-2016). Phylogenetic studies have shown that ZIKV has evolved into African and Asian lineages. The Asian lineage of ZIKV was responsible for the recent epidemics in the Americas. However, the underlying mechanisms through which ZIKV rapidly and explosively spread from Asia to the Americas are unclear. Non-structural protein 1 (NS1) facilitates flavivirus acquisition by mosquitoes from an infected mammalian host and subsequently enhances viral prevalence in mosquitoes. Here we show that NS1 antigenaemia determines ZIKV infectivity in its mosquito vector Aedes aegypti, which acquires ZIKV via a blood meal. Clinical isolates from the most recent outbreak in the Americas were much more infectious in mosquitoes than the FSS13025 strain, which was isolated in Cambodia in 2010. Further analyses showed that these epidemic strains have higher NS1 antigenaemia than the FSS13025 strain because of an alanine-to-valine amino acid substitution at residue 188 in NS1. ZIKV infectivity was enhanced by this amino acid substitution in the ZIKV FSS13025 strain in mosquitoes that acquired ZIKV from a viraemic C57BL/6 mouse deficient in type I and II interferon (IFN) receptors (AG6 mouse). Our results reveal that ZIKV evolved to acquire a spontaneous mutation in its NS1 protein, resulting in increased NS1 antigenaemia. Enhancement of NS1 antigenaemia in infected hosts promotes ZIKV infectivity and prevalence in mosquitoes, which could have facilitated transmission during recent ZIKV epidemics.


Asunto(s)
Aedes/virología , Evolución Biológica , Mosquitos Vectores/virología , Infección por el Virus Zika/transmisión , Infección por el Virus Zika/virología , Virus Zika/patogenicidad , Américas/epidemiología , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Asia/epidemiología , Cambodia/epidemiología , Femenino , Humanos , Estadios del Ciclo de Vida , Ratones , Ratones Endogámicos C57BL , Filogenia , Células Vero , Proteínas no Estructurales Virales/química , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Virus Zika/genética , Virus Zika/aislamiento & purificación , Virus Zika/metabolismo , Infección por el Virus Zika/epidemiología
15.
Proc Natl Acad Sci U S A ; 117(33): 20190-20197, 2020 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-32747564

RESUMEN

Arboviruses maintain high mutation rates due to lack of proofreading ability of their viral polymerases, in some cases facilitating adaptive evolution and emergence. Here we show that, just before its 2013 spread to the Americas, Zika virus (ZIKV) underwent an envelope protein V473M substitution (E-V473M) that increased neurovirulence, maternal-to-fetal transmission, and viremia to facilitate urban transmission. A preepidemic Asian ZIKV strain (FSS13025 isolated in Cambodia in 2010) engineered with the V473M substitution significantly increased neurovirulence in neonatal mice and produced higher viral loads in the placenta and fetal heads in pregnant mice. Conversely, an epidemic ZIKV strain (PRVABC59 isolated in Puerto Rico in 2015) engineered with the inverse M473V substitution reversed the pathogenic phenotypes. Although E-V473M did not affect oral infection of Aedes aegypti mosquitoes, competition experiments in cynomolgus macaques showed that this mutation increased its fitness for viremia generation, suggesting adaptive evolution for human viremia and hence transmission. Mechanistically, the V473M mutation, located at the second transmembrane helix of the E protein, enhances virion morphogenesis. Overall, our study revealed E-V473M as a critical determinant for enhanced ZIKV virulence, intrauterine transmission during pregnancy, and viremia to facilitate urban transmission.


Asunto(s)
Epidemias , Proteínas del Envoltorio Viral/genética , Infección por el Virus Zika/virología , Virus Zika/genética , Virus Zika/patogenicidad , Animales , Femenino , Humanos , Macaca fascicularis , Masculino , Ratones , Ratones Endogámicos C57BL , Mutación , Filogenia , Embarazo , Carga Viral , Virulencia , Virus Zika/fisiología , Infección por el Virus Zika/epidemiología
16.
J Fish Dis ; 46(2): 137-146, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36336976

RESUMEN

Decapod iridescent virus 1 (DIV1), White spot syndrome virus (WSSV), and Enterocytozoon hepatopenaei (EHP) pose serious threats to the shrimp farming. To date, early detection remains an important way to control the occurrence and diffusion of these pathogens. Here, we developed for the first time, a loop-mediated isothermal amplification (LAMP)-based microfluidic chip detection system, which could detect DIV1, WSSV, and EHP simultaneously. The limits of detection (LoD) of the system were 10 copies/reaction for EHP and DIV1, and 102 copies/reaction for WSSV. The entire detection procedure could be completed rapidly in 40 min at 63°C with 100% specificity and had no cross-reaction with other common shrimp pathogens. This newly established method was further validated using 94 Penaeus vannamei clinical samples, which were comparable to a typical qPCR assay and revealed good stability and reproducibility. These results illustrate that this LAMP microfluidic chip detection system allows rapid triplex pathogen analysis and could satisfy the demands of the field and routine diagnoses in aquaculture.


Asunto(s)
Enfermedades de los Peces , Penaeidae , Virosis , Animales , Microfluídica , Técnicas de Amplificación de Ácido Nucleico/veterinaria , Técnicas de Amplificación de Ácido Nucleico/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
PLoS Med ; 19(6): e1004026, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35696440

RESUMEN

BACKGROUND: Despite availability of clinical practice guidelines for hypertension management, blood pressure (BP) control remains sub-optimal (<30%) even in high-income countries. This study aims to assess the effectiveness of a potentially scalable multicomponent intervention integrated into primary care system compared to usual care on BP control. METHODS AND FINDINGS: A cluster-randomized controlled trial was conducted in 8 government clinics in Singapore. The trial enrolled 916 patients aged ≥40 years with uncontrolled hypertension (systolic BP (SBP) ≥140 mmHg or diastolic BP (DBP) ≥90 mmHg). Multicomponent intervention consisted of physician training in risk-based treatment of hypertension, subsidized losartan-HCTZ single-pill combination (SPC) medications, nurse training in motivational conversations (MCs), and telephone follow-ups. Usual care (controls) comprised of routine care in the clinics, no MC or telephone follow-ups, and no subsidy on SPCs. The primary outcome was mean SBP at 24 months' post-baseline. Four clinics (447 patients) were randomized to intervention and 4 (469) to usual care. Patient enrolment commenced in January 2017, and follow-up was during December 2018 to September 2020. Analysis used intention-to-treat principles. The primary outcome was SBP at 24 months. BP at baseline, 12 and 24 months was modeled at the patient level in a likelihood-based, linear mixed model repeated measures analysis with treatment group, follow-up, treatment group × follow-up interaction as fixed effects, and random cluster (clinic) effects. A total of 766 (83.6%) patients completed 2-year follow-up. A total of 63 (14.1%) and 87 (18.6%) patients in intervention and in usual care, respectively, were lost to follow-up. At 24 months, the adjusted mean SBP was significantly lower in the intervention group compared to usual care (-3.3 mmHg; 95% CI: -6.34, -0.32; p = 0.03). The intervention led to higher BP control (odds ratio 1.51; 95% CI: 1.10, 2.09; p = 0.01), lower odds of high (>20%) 10-year cardiovascular risk score (OR 0.67; 95% CI: 0.47, 0.97; p = 0.03), and lower mean log albuminuria (-0.22; 95% CI: -0.41, -0.02; p = 0.03). Mean DBP, mortality rates, and serious adverse events including hospitalizations were not different between groups. The main limitation was no masking in the trial. CONCLUSIONS: A multicomponent intervention consisting of physicians trained in risk-based treatment, subsidized SPC medications, nurse-delivered motivational conversation, and telephone follow-ups improved BP control and lowered cardiovascular risk. Wide-scale implementation of a multicomponent intervention such as the one in our trial is likely to reduce hypertension-related morbidity and mortality globally. TRIAL REGISTRATION: Trial Registration: Clinicaltrials.gov NCT02972619.


Asunto(s)
Hipertensión , Antihipertensivos/efectos adversos , Presión Sanguínea , Humanos , Hipertensión/tratamiento farmacológico , Funciones de Verosimilitud , Atención Primaria de Salud , Singapur
18.
BMC Med ; 20(1): 13, 2022 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-35039035

RESUMEN

BACKGROUND: Recaticimab (SHR-1209, a humanized monoclonal antibody against PCSK9) showed robust LDL-C reduction in healthy volunteers. This study aimed to further assess the efficacy and safety of recaticimab in patients with hypercholesterolemia. METHODS: In this randomized, double-blind, placebo-controlled phase 1b/2 trial, patients receiving stable dose of atorvastatin with an LDL-C level of 2.6 mmol/L or higher were randomized in a ratio of 5:1 to subcutaneous injections of recaticimab or placebo at different doses and schedules. Patients were recruited in the order of 75 mg every 4 weeks (75Q4W), 150Q8W, 300Q12W, 150Q4W, 300Q8W, and 450Q12W. The primary endpoint was percentage change in LDL-C from the baseline to end of treatment (i.e., at week 16 for Q4W and Q8W schedule and at week 24 for Q12W schedule). RESULTS: A total of 91 patients were enrolled and received recaticimab and 19 received placebo. The dose of background atorvastatin in all 110 patients was 10 or 20 mg/day. The main baseline LDL-C ranged from 3.360 to 3.759 mmol/L. The least-squares mean percentage reductions in LDL-C from baseline to end of treatment relative to placebo for recaticimab groups at different doses and schedules ranged from -48.37 to -59.51%. No serious treatment-emergent adverse events (TEAEs) occurred. The most common TEAEs included upper respiratory tract infection, increased alanine aminotransferase, increased blood glucose, and increased gamma-glutamyltransferase. CONCLUSION: Recaticimab as add-on to moderate-intensity statin therapy significantly and substantially reduced the LDL-C level with an infrequent administration schedule (even given once every 12 weeks), compared with placebo. TRIAL REGISTRATION: ClinicalTrials.gov , number NCT03944109.


Asunto(s)
Hipercolesterolemia , Inhibidores de PCSK9 , Anticuerpos Monoclonales Humanizados/efectos adversos , Método Doble Ciego , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/administración & dosificación , Hipercolesterolemia/tratamiento farmacológico , Inhibidores de PCSK9/efectos adversos , Resultado del Tratamiento
20.
New Phytol ; 229(4): 2260-2272, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33037676

RESUMEN

Plants use their innate immune system to defend against phytopathogens. As a part of this, pattern triggered-immunity is activated via pattern recognition receptor (PRR) detection of pathogen-associated molecular patterns (PAMPs). Although an increasing number of PAMPs have been identified, the PRRs for their recognition remain largely unknown. In the present study, we report a receptor-like protein RE02 (Response to VmE02) in Nicotiana benthamiana, which mediates the perception of VmE02, a PAMP previously identified from the phytopathogenic fungus Valsa mali, using virus-induced gene silencing (VIGS), co-immunoprecipitation, pull-down and microscale thermophoresis assays. We show that silencing of RE02 markedly attenuated VmE02-triggred cell death and immune responses. RE02 specifically interacted with VmE02 in vivo and in vitro, and it displayed a high affinity for VmE02. Formation of a complex with the receptor-like kinases SOBIR1 and BAK1 was essential for RE02 to perceive VmE02. Moreover, RE02-silenced plants exhibited enhanced susceptibility to both the oomycete Phytophthora capsici and the fungus Sclerotinia sclerotiorum, while overexpression of RE02 increased plant resistance to these pathogens. Together, our results indicate that the PAMP VmE02 and the receptor-like protein RE02 represent a new ligand-receptor pair in plant immunity, and that RE02 represents a promising target for engineering disease resistance.


Asunto(s)
Nicotiana , Moléculas de Patrón Molecular Asociado a Patógenos , Ascomicetos , Enfermedades de las Plantas , Inmunidad de la Planta , Proteínas de Plantas/genética
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