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1.
Genes Dev ; 37(19-20): 883-900, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37890975

RESUMO

Loss-of-function mutations in MECP2 cause Rett syndrome (RTT), a severe neurological disorder that mainly affects girls. Mutations in MECP2 do occur in males occasionally and typically cause severe encephalopathy and premature lethality. Recently, we identified a missense mutation (c.353G>A, p.Gly118Glu [G118E]), which has never been seen before in MECP2, in a young boy who suffered from progressive motor dysfunction and developmental delay. To determine whether this variant caused the clinical symptoms and study its functional consequences, we established two disease models, including human neurons from patient-derived iPSCs and a knock-in mouse line. G118E mutation partially reduces MeCP2 abundance and its DNA binding, and G118E mice manifest RTT-like symptoms seen in the patient, affirming the pathogenicity of this mutation. Using live-cell and single-molecule imaging, we found that G118E mutation alters MeCP2's chromatin interaction properties in live neurons independently of its effect on protein levels. Here we report the generation and characterization of RTT models of a male hypomorphic variant and reveal new insight into the mechanism by which this pathological mutation affects MeCP2's chromatin dynamics. Our ability to quantify protein dynamics in disease models lays the foundation for harnessing high-resolution single-molecule imaging as the next frontier for developing innovative therapies for RTT and other diseases.


Assuntos
Cromatina , Síndrome de Rett , Feminino , Humanos , Masculino , Camundongos , Animais , Cromatina/metabolismo , Encéfalo/metabolismo , Proteína 2 de Ligação a Metil-CpG/genética , Síndrome de Rett/genética , Mutação , Neurônios/metabolismo
2.
Mol Ther ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38894543

RESUMO

Self-amplifying mRNA (SAM) vaccines can be rapidly deployed in the event of disease outbreaks. A legitimate safety concern is the potential for recombination between alphavirus-based SAM vaccines and circulating viruses. This theoretical risk needs to be assessed in the regulatory process for SAM vaccine approval. Herein, we undertake extensive in vitro and in vivo assessments to explore recombination between SAM vaccine and a wide selection of alphaviruses and a coronavirus. SAM vaccines were found to effectively limit alphavirus co-infection through superinfection exclusion, although some co-replication was still possible. Using sensitive cell-based assays, replication-competent alphavirus chimeras were generated in vitro as a result of rare, but reproducible, RNA recombination events. The chimeras displayed no increased fitness in cell culture. Viable alphavirus chimeras were not detected in vivo in C57BL/6J, Rag1-/- and Ifnar-/- mice, in which high levels of SAM vaccine and alphavirus co-replicated in the same tissue. Furthermore, recombination between a SAM-spike vaccine and a swine coronavirus was not observed. In conclusion we state that although the ability of SAM vaccines to recombine with alphaviruses might be viewed as an environmental safety concern, several key factors substantially mitigate against in vivo emergence of chimeric viruses from SAM vaccine recipients.

3.
Nano Lett ; 24(8): 2488-2495, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38198618

RESUMO

Electromagnetic chirality transfer represents an effective means of the nanoscale manipulation of optical chirality. While most of the previous reports have exclusively focused on the circular dichroism (CD) transfer from UV-responsive chiral molecules toward visible-resonant achiral colloidal nanoparticles, here we demonstrate a reverse process in which plasmonic chirality can be transferred to achiral molecules, either upward from visible to UV or downward from visible to near infrared (NIR). By hybridizing achiral UV- or NIR-responsive dye molecules with chiral metal nanoparticles in solution, we observe a chiral-plasmon-induced CD (CPICD) signal at the intrinsically achiral molecular absorption bands. Full-wave electromagnetic modeling reveals that both near-field Coulomb interaction and far-field radiative coupling contribute to the observed CPICD, indicating that the mechanism considered here is universal for different material systems and types of optical resonances. Our study provides a set of design guidelines for broadband nanophotonic chiral sensing from the UV to NIR spectral regime.

4.
Small ; 20(25): e2311639, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38204283

RESUMO

The development of ultraviolet circularly polarized light (UVCPL) sources has the potential to benefit plenty of practical applications but remains a challenge due to limitations in available material systems and a limited understanding of the excited state chirality transfer. Herein, by constructing hybrid structures of the chiral perovskite CsPbBr3 nanoplatelets and organic molecules, excited state chirality transfer is achieved, either via direct binding or triplet energy transfer, leading to efficient UVCPL emission. The underlying photophysical mechanisms of these two scenarios are clarified by comprehensive optical studies. Intriguingly, UVCPL realized via the triple energy transfer, followed by the triplet-triplet annihilation upconversion processes, demonstrates a 50-fold enhanced dissymmetry factor glum. Furthermore, stereoselective photopolymerization of diacetylene monomer is demonstrated by using such efficient UVCPL. This study provides both novel insights and a practical approach for realizing UVCPL, which can also be extended to other material systems and spectral regions, such as visible and near-infrared.

5.
J Virol ; 97(3): e0160122, 2023 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-36883812

RESUMO

Mayaro virus (MAYV) is a mosquito-transmitted alphavirus that causes often debilitating rheumatic disease in tropical Central and South America. There are currently no licensed vaccines or antiviral drugs available for MAYV disease. Here, we generated Mayaro virus-like particles (VLPs) using the scalable baculovirus-insect cell expression system. High-level secretion of MAYV VLPs in the culture fluid of Sf9 insect cells was achieved, and particles with a diameter of 64 to 70 nm were obtained after purification. We characterize a C57BL/6J adult wild-type mouse model of MAYV infection and disease and used this model to compare the immunogenicity of VLPs from insect cells with that of VLPs produced in mammalian cells. Mice received two intramuscular immunizations with 1 µg of nonadjuvanted MAYV VLPs. Potent neutralizing antibody responses were generated against the vaccine strain, BeH407, with comparable activity seen against a contemporary 2018 isolate from Brazil (BR-18), whereas neutralizing activity against chikungunya virus was marginal. Sequencing of BR-18 illustrated that this virus segregates with genotype D isolates, whereas MAYV BeH407 belongs to genotype L. The mammalian cell-derived VLPs induced higher mean neutralizing antibody titers than those produced in insect cells. Both VLP vaccines completely protected adult wild-type mice against viremia, myositis, tendonitis, and joint inflammation after MAYV challenge. IMPORTANCE Mayaro virus (MAYV) is associated with acute rheumatic disease that can be debilitating and can evolve into months of chronic arthralgia. MAYV is believed to have the potential to emerge as a tropical public health threat, especially if it develops the ability to be efficiently transmitted by urban mosquito vectors, such as Aedes aegypti and/or Aedes albopictus. Here, we describe a scalable virus-like particle vaccine against MAYV that induced neutralizing antibodies against a historical and a contemporary isolate of MAYV and protected mice against infection and disease, providing a potential new intervention for MAYV epidemic preparedness.


Assuntos
Aedes , Alphavirus , Vírus Chikungunya , Doenças Reumáticas , Vacinas de Partículas Semelhantes a Vírus , Animais , Camundongos , Vacinas de Partículas Semelhantes a Vírus/genética , Camundongos Endogâmicos C57BL , Alphavirus/genética , Brasil , Anticorpos Neutralizantes , Mamíferos
6.
PLoS Pathog ; 18(9): e1010867, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36155667

RESUMO

How well mouse models recapitulate the transcriptional profiles seen in humans remains debatable, with both conservation and diversity identified in various settings. Herein we use RNA-Seq data and bioinformatics approaches to analyze the transcriptional responses in SARS-CoV-2 infected lungs, comparing 4 human studies with the widely used K18-hACE2 mouse model, a model where hACE2 is expressed from the mouse ACE2 promoter, and a model that uses a mouse adapted virus and wild-type mice. Overlap of single copy orthologue differentially expressed genes (scoDEGs) between human and mouse studies was generally poor (≈15-35%). Rather than being associated with batch, sample treatment, viral load, lung damage or mouse model, the poor overlaps were primarily due to scoDEG expression differences between species. Importantly, analyses of immune signatures and inflammatory pathways illustrated highly significant concordances between species. As immunity and immunopathology are the focus of most studies, these mouse models can thus be viewed as representative and relevant models of COVID-19.


Assuntos
COVID-19 , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/genética , Modelos Animais de Doenças , Expressão Gênica , Humanos , Pulmão , Camundongos , Camundongos Transgênicos , Peptidil Dipeptidase A/metabolismo , SARS-CoV-2/genética
7.
Appl Environ Microbiol ; 90(2): e0204823, 2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38289131

RESUMO

Bacterial and eukaryotic HtrAs can act as an extracytoplasmic protein quality control (PQC) system to help cells survive in stress conditions, but the functions of archaeal HtrAs remain unknown. Particularly, haloarchaea route most secretory proteins to the Tat pathway, enabling them to fold properly in well-controlled cytoplasm with cytosolic PQC systems before secretion. It is unclear whether HtrAs are required for haloarchaeal survival and stress response. The haloarchaeon Natrinema gari J7-2 encodes three Tat signal peptide-bearing HtrAs (NgHtrA, NgHtrB, and NgHtrC), and the signal peptides of NgHtrA and NgHtrC contain a lipobox. Here, the in vitro analysis reveals that the three HtrAs show different profiles of temperature-, salinity-, and metal ion-dependent proteolytic activities and could exhibit chaperone-like activities to prevent the aggregation of reduced lysozyme when their proteolytic activities are inhibited at low temperatures or the active site is disrupted. The gene deletion and complementation assays reveal that NgHtrA and NgHtrC are essential for the survival of strain J7-2 at elevated temperature and/or high salinity and contribute to the resistance of this haloarchaeon to zinc and inhibitory substances generated from tryptone. Mutational analysis shows that the lipobox mediates membrane anchoring of NgHtrA or NgHtrC, and both the membrane-anchored and free extracellular forms of the two enzymes are involved in the stress resistance of strain J7-2, depending on the stress conditions. Deletion of the gene encoding NgHtrB in strain J7-2 causes no obvious growth defect, but NgHtrB can functionally substitute for NgHtrA or NgHtrC under some conditions.IMPORTANCEHtrA-mediated protein quality control plays an important role in the removal of aberrant proteins in the extracytoplasmic space of living cells, and the action mechanisms of HtrAs have been extensively studied in bacteria and eukaryotes; however, information about the function of archaeal HtrAs is scarce. Our results demonstrate that three HtrAs of the haloarchaeon Natrinema gari J7-2 possess both proteolytic and chaperone-like activities, confirming that the bifunctional nature of HtrAs is conserved across all three domains of life. Moreover, we found that NgHtrA and NgHtrC are essential for the survival of strain J7-2 under stress conditions, while NgHtrB can serve as a substitute for the other two HtrAs under certain circumstances. This study provides the first biochemical and genetic evidence of the importance of HtrAs for the survival of haloarchaea in response to stresses.


Assuntos
Halobacteriaceae , Temperatura Alta , Salinidade , Halobacteriaceae/genética , Sinais Direcionadores de Proteínas
8.
Appl Environ Microbiol ; : e0074124, 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38953660

RESUMO

To cope with a high-salinity environment, haloarchaea generally employ the twin-arginine translocation (Tat) pathway to transport secretory proteins across the cytoplasm membrane in a folded state, including Tat-dependent extracellular subtilases (halolysins) capable of autocatalytic activation. Some halolysins, such as SptA of Natrinema gari J7-2, are produced at late-log phase to prevent premature enzyme activation and proteolytic damage of cellular proteins in haloarchaea; however, the regulation mechanism for growth phase-dependent expression of halolysins remains largely unknown. In this study, a DNA-protein pull-down assay was performed to identify the proteins binding to the 5'-flanking sequence of sptA encoding halolysin SptA in strain J7-2, revealing a TrmBL2-like transcription factor (NgTrmBL2). The ΔtrmBL2 mutant of strain J7-2 showed a sharp decrease in the production of SptA, suggesting that NgTrmBL2 positively regulates sptA expression. The purified recombinant NgTrmBL2 mainly existed as a dimer although monomeric and higher-order oligomeric forms were detected by native-PAGE analysis. The results of electrophoretic mobility shift assays (EMSAs) showed that NgTrmBL2 binds to the 5'-flanking sequence of sptA in a non-specific and concentration-dependent manner and exhibits an increased DNA-binding affinity with the increase in KCl concentration. Moreover, we found that a distal cis-regulatory element embedded in the neighboring upstream gene negatively regulates trmBL2 expression and thus participates in the growth phase-dependent biosynthesis of halolysin SptA. IMPORTANCE: Extracellular proteases play important roles in nutrient metabolism, processing of functional proteins, and antagonism of haloarchaea, but no transcription factor involved in regulating the expression of haloaechaeal extracellular protease has been reported yet. Here we report that a TrmBL2-like transcription factor (NgTrmBL2) mediates the growth phase-dependent expression of an extracellular protease, halolysin SptA, of haloarchaeon Natrinema gari J7-2. In contrast to its hyperthermophilic archaeal homologs, which are generally considered to be global transcription repressors, NgTrmBL2 functions as a positive regulator for sptA expression. This study provides new clues about the transcriptional regulation mechanism of extracellular protease in haloarchaea and the functional diversity of archaeal TrmBL2.

9.
PLoS Biol ; 19(4): e3001201, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33872300

RESUMO

Most vertebrate RNA viruses show pervasive suppression of CpG and UpA dinucleotides, closely resembling the dinucleotide composition of host cell transcriptomes. In contrast, CpG suppression is absent in both invertebrate mRNA and RNA viruses that exclusively infect arthropods. Arthropod-borne (arbo) viruses are transmitted between vertebrate hosts by invertebrate vectors and thus encounter potentially conflicting evolutionary pressures in the different cytoplasmic environments. Using a newly developed Zika virus (ZIKV) model, we have investigated how demands for CpG suppression in vertebrate cells can be reconciled with potentially quite different compositional requirements in invertebrates and how this affects ZIKV replication and transmission. Mutant viruses with synonymously elevated CpG or UpA dinucleotide frequencies showed attenuated replication in vertebrate cell lines, which was rescued by knockout of the zinc-finger antiviral protein (ZAP). Conversely, in mosquito cells, ZIKV mutants with elevated CpG dinucleotide frequencies showed substantially enhanced replication compared to wild type. Host-driven effects on virus replication attenuation and enhancement were even more apparent in mouse and mosquito models. Infections with CpG- or UpA-high ZIKV mutants in mice did not cause typical ZIKV-induced tissue damage and completely protected mice during subsequent challenge with wild-type virus, which demonstrates their potential as live-attenuated vaccines. In contrast, the CpG-high mutants displayed enhanced replication in Aedes aegypti mosquitoes and a larger proportion of mosquitoes carried infectious virus in their saliva. These findings show that mosquito cells are also capable of discriminating RNA based on dinucleotide composition. However, the evolutionary pressure on the CpG dinucleotides of viral genomes in arthropod vectors directly opposes the pressure present in vertebrate host cells, which provides evidence that an adaptive compromise is required for arbovirus transmission. This suggests that the genome composition of arbo flaviviruses is crucial to maintain the balance between high-level replication in the vertebrate host and persistent replication in the mosquito vector.


Assuntos
Evolução Molecular , Genoma Viral/genética , Interações Hospedeiro-Patógeno/genética , Zika virus/genética , Células A549 , Aedes/virologia , Animais , Composição de Bases/fisiologia , Sequência de Bases/genética , Linhagem Celular , Chlorocebus aethiops , Ilhas de CpG/fisiologia , Fosfatos de Dinucleosídeos/análise , Fosfatos de Dinucleosídeos/genética , Adaptação ao Hospedeiro/genética , Humanos , Masculino , Mamíferos/virologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mosquitos Vetores/genética , Mosquitos Vetores/virologia , RNA Viral/química , RNA Viral/genética , Seleção Genética/fisiologia , Células Vero , Infecção por Zika virus/genética , Infecção por Zika virus/transmissão , Infecção por Zika virus/virologia
10.
J Environ Manage ; 364: 121428, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38879966

RESUMO

The use of wetland plants in the context of phytoremediation is effective in the removal of antibiotics from contaminated water. However, the effectiveness and efficiency of many of these plants in the removal of antibiotics remain undetermined. In this study, the effectiveness of two plants-Phragmites australis and Iris pseudacorus-in the removal of tetracycline (TC) in hydroponic systems was investigated. The uptake of TC at the roots of I. pseudacorus and P. australis occurred at concentrations of 588.78 and 106.70 µg/g, respectively, after 7-day exposure. The higher uptake of TC in the root of I. pseudacorus may be attributed to its higher secretion of root exudates, which facilitate conditions conducive to the reproduction of microorganisms. These rhizosphere-linked microorganisms then drove the TC uptake, which was higher than that in the roots of P. australis. By elucidating the mechanisms underlying these uptake-linked outcomes, we found that the uptake of TC for both plants was significantly suppressed by metabolic and aquaporin inhibition, suggesting uptake and transport of TC were active (energy-dependent) and passive (aquaporin-dominated) processes, respectively. The subcellular distribution patterns of I. pseudacorus and P. australis in the roots were different, as expressed by differences in organelles, cell wall concentration levels, and transport-related dynamics. Additionally, the microbe-driven enhancement of the remediation capacities of the plants was studied comprehensively via a combined microbial-phytoremediation hydroponic system. We confirmed that the microbial agents increased the secretion of root exudates, promoting the variation of TC chemical speciation and thus enhancing the active transport of TC. These results contribute toward the improved application of wetland plants in the context of antibiotic phytoremediation.


Assuntos
Biodegradação Ambiental , Raízes de Plantas , Tetraciclina , Áreas Alagadas , Tetraciclina/metabolismo , Raízes de Plantas/metabolismo , Poluentes Químicos da Água/metabolismo , Rizosfera , Hidroponia
11.
Angew Chem Int Ed Engl ; 63(24): e202401943, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38594205

RESUMO

Electrochemical C-N coupling reaction based on carbon dioxide and nitrate have been emerged as a new "green synthetic strategy" for the synthesis of urea, but the catalytic efficiency is seriously restricted by the inherent scaling relations of adsorption energies of the active sites, the improvement of catalytic activity is frequently accompanied by the decrease in selectivity. Herein, a doping engineering strategy was proposed to break the scaling relationship of intermediate binding and minimize the kinetic barrier of C-N coupling. A thus designed SrCo0.39Ru0.61O3-δ catalyst achieves a urea yield rate of 1522 µg h-1 mgcat. -1 and faradic efficiency of 34.1 % at -0.7 V versus reversible hydrogen electrode. A series of characterizations revealed that Co doping not only induces lattice distortion but also creates rich oxygen vacancies (OV) in the SrRuO3. The oxygen vacancies weaken the adsorption of *CO and *NH2 intermediates on the Co and Ru sites respectively, and the strain effects over the Co-Ru dual sites promoting the occurrence of C-N coupling of the two monomers instead of selective hydrogenating to form by-products. This work presents an insight into molecular coupling reactions towards urea synthesis via the doping engineering on SrRuO3.

12.
Funct Integr Genomics ; 23(2): 100, 2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-36961647

RESUMO

Ultrasound has few reports on its application in prediction of microvascular invasion (MVI) in hepatocellular carcinoma (HCC). The purpose of this study was to explore the diagnostic efficacies of preoperative ultrasound and magnetic resonance imaging (MRI) for HCC MVI and compare these two imaging methods for the diagnosis of this condition. The clinical and preoperative ultrasound and MR imaging data of 26 patients with newly diagnosed HCC were collected between October 2020 and October 2021. According to the gold standard (postoperative pathology), the patients were divided into MVI-positive and MVI-negative groups, and the efficacies of ultrasound and MRI in diagnosing HCC MVI and the consistency between the two imaging modalities were analyzed. For the preoperative diagnosis of MVI using ultrasound, the sensitivity was 93.33%, the specificity was 81.82%, and the accuracy was 88.46%. For preoperative MRI, the sensitivity was 66.67%, the specificity was 100%, and the accuracy was 80.77%. In diagnosing MVI, the two methods had significantly different efficacy (P = 0.031). Ultrasound and MRI have high diagnostic efficiency for MVI, but the accuracy of preoperative MRI was lower than that of preoperative ultrasound. These results indicate that ultrasound has a certain guiding significance in the diagnosis of HCC MVI.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/irrigação sanguínea , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/irrigação sanguínea , Neoplasias Hepáticas/patologia , Invasividade Neoplásica/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos
13.
PLoS Pathog ; 17(7): e1009723, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34214142

RESUMO

SARS-CoV-2 uses the human ACE2 (hACE2) receptor for cell attachment and entry, with mouse ACE2 (mACE2) unable to support infection. Herein we describe an ACE2-lentivirus system and illustrate its utility for in vitro and in vivo SARS-CoV-2 infection models. Transduction of non-permissive cell lines with hACE2 imparted replication competence, and transduction with mACE2 containing N30D, N31K, F83Y and H353K substitutions, to match hACE2, rescued SARS-CoV-2 replication. Intrapulmonary hACE2-lentivirus transduction of C57BL/6J mice permitted significant virus replication in lung epithelium. RNA-Seq and histological analyses illustrated that this model involved an acute inflammatory disease followed by resolution and tissue repair, with a transcriptomic profile similar to that seen in COVID-19 patients. hACE2-lentivirus transduction of IFNAR-/- and IL-28RA-/- mouse lungs was used to illustrate that loss of type I or III interferon responses have no significant effect on virus replication. However, their importance in driving inflammatory responses was illustrated by RNA-Seq analyses. We also demonstrate the utility of the hACE2-lentivirus transduction system for vaccine evaluation in C57BL/6J mice. The ACE2-lentivirus system thus has broad application in SARS-CoV-2 research, providing a tool for both mutagenesis studies and mouse model development.


Assuntos
Enzima de Conversão de Angiotensina 2 , COVID-19 , Perfilação da Expressão Gênica , Lentivirus , SARS-CoV-2 , Transdução Genética , Enzima de Conversão de Angiotensina 2/biossíntese , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/genética , COVID-19/metabolismo , Chlorocebus aethiops , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Knockout , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Células Vero
14.
PLoS Pathog ; 17(7): e1009788, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34310650

RESUMO

Zika virus (ZIKV) strains are classified into the African and Asian genotypes. The higher virulence of the African MR766 strain, which has been used extensively in ZIKV research, in adult IFNα/ß receptor knockout (IFNAR-/-) mice is widely viewed as an artifact associated with mouse adaptation due to at least 146 passages in wild-type suckling mouse brains. To gain insights into the molecular determinants of MR766's virulence, a series of genes from MR766 were swapped with those from the Asian genotype PRVABC59 isolate, which is less virulent in IFNAR-/- mice. MR766 causes 100% lethal infection in IFNAR-/- mice, but when the prM gene of MR766 was replaced with that of PRVABC59, the chimera MR/PR(prM) showed 0% lethal infection. The reduced virulence was associated with reduced neuroinvasiveness, with MR766 brain titers ≈3 logs higher than those of MR/PR(prM) after subcutaneous infection, but was not significantly different in brain titers of MR766 and MR/PR(prM) after intracranial inoculation. MR/PR(prM) also showed reduced transcytosis when compared with MR766 in vitro. The high neuroinvasiveness of MR766 in IFNAR-/- mice could be linked to the 10 amino acids that differ between the prM proteins of MR766 and PRVABC59, with 5 of these changes affecting positive charge and hydrophobicity on the exposed surface of the prM protein. These 10 amino acids are highly conserved amongst African ZIKV isolates, irrespective of suckling mouse passage, arguing that the high virulence of MR766 in adult IFNAR-/- mice is not the result of mouse adaptation.


Assuntos
Proteínas do Envelope Viral/genética , Virulência/genética , Infecção por Zika virus/virologia , Zika virus/genética , Zika virus/patogenicidade , Animais , Barreira Hematoencefálica , Permeabilidade Capilar , Genótipo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Zika virus/metabolismo
15.
Langmuir ; 39(46): 16415-16421, 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37933492

RESUMO

Non-noble metal oxides have emerged as potential candidate electrocatalysts for acidic oxygen evolution reactions (OERs) due to their earth abundance; however, improving their catalytic activity and stability simultaneously in strong acidic electrolytes is still a major challenge. In this work, we report Co3O4@carbon core-shell nanoparticles on 2D graphite sheets (Co3O4@C-GS) as mixed-dimensional hybrid electrocatalysts for acidic OER. The obtained Co3O4@C-GS catalyst exhibits a low overpotential of 350 mV and maintains stability for 20 h at a current density of 10 mA cm-2 in H2SO4 (pH = 1) electrolyte. X-ray photoelectron and X-ray absorption spectroscopies illustrate that the higher content of Co3+ sites boosts acidic OER. Operando Raman spectroscopy reveals that the catalytic stability of Co3O4@C nanoparticles during the acidic OER is enhanced by the introduction of graphite sheets. This interface engineering of non-noble metal sites with high valence states provides an efficient approach to boost the catalytic activity and enhance the stability of noble-metal-free electrocatalysts for acidic OER.

16.
Acta Pharmacol Sin ; 44(7): 1442-1454, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36658427

RESUMO

Acute kidney injury (AKI) caused by anti-tumor drugs, such as cisplatin, is a severe complication with no effective treatment currently, leading to the reduction or discontinuation of chemotherapy. Natural products or herbal medicines are gradually considered as promising agents against cisplatin-induced AKI with the advantages of multi-targeting, multi-effects, and less resistance. In this study, we investigated the effects of kaempferide, a natural flavonoid extracted from the rhizome of Kaempferia galanga, in experimental AKI models in vitro and in vivo. We first conducted pharmacokinetic study in mice and found a relative stable state of kaempferide with a small amount of conversion into kaempferol. We showed that both kaempferide (10 µM) and kaempferol (10 µM) significantly inhibited cisplatin-caused injuries in immortalized proximal tubule epithelial cell line HK-2. In AKI mice induced by injection of a single dose of cisplatin (15 mg/kg), oral administration of kaempferide (50 mg/kg) either before or after cisplatin injection markedly improved renal function, and ameliorated renal tissue damage. We demonstrated that kaempferide inhibited oxidative stress and induced autophagy in cisplatin-treated mice and HK-2 cells, thus increasing tubular cell viability and decreasing immune responses to attenuate the disease progression. In addition, treatment with kaempferide significantly ameliorated ischemia-reperfusion-induced renal injury in vitro and in vivo. We conclude that kaempferide is a promising natural product for treating various AKI. This study has great implications for promotion of its use in healthcare products, and help to break through the limited use of cisplatin in the clinic.


Assuntos
Injúria Renal Aguda , Cisplatino , Camundongos , Animais , Cisplatino/farmacologia , Quempferóis/farmacologia , Quempferóis/uso terapêutico , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/tratamento farmacológico , Injúria Renal Aguda/patologia , Estresse Oxidativo , Autofagia , Apoptose , Camundongos Endogâmicos C57BL
17.
Clin Lab ; 69(10)2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37844047

RESUMO

The RH blood group system is the most complex with over 50 antigens. So far over hundreds of RhCE variant alleles have been described resulting in weakened and/or partial expression of RhCE antigens [1], some variant Rh phenotypes are caused by exchange of genetic material between the RHD and RHCE genes, resulting in many hybrid genes, other phenotypes result from missense mutations. Variant alleles encode altered phenotypes with either weakened antigens, lacked antigens, or unexpected antigens. Besides, the mutation of RH blood group genes may lead to the changes of Rh antigen epitopes. RHCE gene mutations or polymorphisms may bring about altered RH antigens in quality and quantity [2]. Serologic weaknesses or discrepancies are regularly faced by blood transfusion laboratories, and molecular background explaining this feature can be precisely characterized only by the molecular biological methods.


Assuntos
Antígenos de Grupos Sanguíneos , Antígenos E da Hepatite B , Humanos , Antígenos E da Hepatite B/genética , Alelos , Antígenos de Grupos Sanguíneos/genética , Sistema do Grupo Sanguíneo Rh-Hr/genética , Polimorfismo Genético , Antígenos
18.
Heart Surg Forum ; 26(2): E141-E147, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36972598

RESUMO

BACKGROUND: The risk of coronary artery disease (CAD) in different valve dysfunction has been unclear. METHODS: We reviewed patients, who underwent valve heart surgery and coronary angiography from 2008 to 2021, at our center. RESULTS: A total of 7,932 patients were included in the present study, and 1,332 (16.8%) had CAD. The mean age of the study cohort was 60.5±7.9 years, and 4,206 (53.0%) were male. CAD was 21.4% in aortic disease, 16.2% in mitral valve disease, 11.8% in isolated tricuspid valve disease, and 13.0% in combined aortic and mitral valve disease. Patients with aortic stenosis were older than those with regurgitation (63.6±7.4 years vs. 59.5±8.2 years, P < 0.001), and the CAD risks also were higher (28.0% vs. 19.2%, P < 0.001). The age difference was minimal (60.6±8.2 years vs. 59.5±6.7 years, P = 0.002) between patients with mitral valve regurgitation and stenosis, but the risks of CAD were twice high in regurgitation (20.2% vs. 10.5%, P < 0.001). When the type of valve impairment was not considered, non-rheumatic etiology, advanced age, male sex, hypertension, and diabetes were independent predictors of CAD. CONCLUSION: In patients undergoing valve surgery, the prevalence of CAD was influenced by conventional risk factors. Importantly, CAD also was associated with the type and etiology of valve diseases.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Doença da Artéria Coronariana , Doenças das Valvas Cardíacas , Insuficiência da Valva Mitral , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico , Doença da Artéria Coronariana/epidemiologia , Prevalência , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/epidemiologia , Doenças das Valvas Cardíacas/cirurgia , Insuficiência da Valva Mitral/cirurgia , Fatores de Risco
19.
Nano Lett ; 22(20): 8109-8114, 2022 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-36214567

RESUMO

The construction of luminescent gold nanoparticles (AuNPs) with highly redshifted emission in the second near-infrared window (NIR-II) and good biocompatibility is still challenging. Herein, using an amphiphilic block copolymer (ABC) template with controllable hydrophobic interactions in the diverse forms of unimers and micelles, we report a facile strategy for redshifting the emission and enhancing the biological interactions of luminescent AuNPs. While the uniform clusters of NIR-II AuNPs are formed in situ inside the hydrophobic cores of ABC micelles with strong interparticle hydrophobic interactions and enhanced emission at 1080 nm with a high quantum yield (QY) of 1.6%, the rigid NIR-II AuNPs are generated with strong intraparticle hydrophobic interactions as ABC unimers on the surface, leading to a redshifted emission of 1280 nm with a QY of 0.25% and enhancing the affinities toward injured intestinal mucosa in colitis imaging. These findings open new possibilities for the design of highly redshifted luminescent AuNPs with enhanced biological interactions.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Ouro/química , Micelas , Nanopartículas Metálicas/química , Luminescência , Nanopartículas/química , Interações Hidrofóbicas e Hidrofílicas
20.
Angew Chem Int Ed Engl ; 62(10): e202214720, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36652185

RESUMO

A precise understanding of nano-bio interactions in the sub-nanometer regime is necessary for advancements in nanomedicine. However, this is currently hindered by the control of the nanoparticle size in the sub-nanometer regime. Herein, we report a facile in situ Mn2+ -guided centrifugation strategy for the synthesis of large-scale ultrasmall gold nanoparticles (AuNPs) with a precisely controlled size gradient at the sub-nanometer regime. With the discovery that [Mn(OH)]+ , especially metallic manganese (Mn0 @[Mn(OH)]+ ) nanoparticles, could selectively interact with larger AuNPs through synergistic coordination and hydrogen bonding to form aggregates, we also realized the fast (<1 h) synthesis of water-soluble atomically precise Au25 with high yields (>56 %). We further demonstrated that sub-nanometer size differences (approximately 0.5 nm) significantly alter non-specific phagocytosis of AuNPs in the reticuloendothelial system macrophages, elimination rate, and nanotoxicology.

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