RESUMO
Leukemogenesis is proposed to be a multistep process by which normal hematopoietic stem and progenitor cells are transformed into full-blown leukemic cells, the details of which are not fully understood. Here, we performed serial single-cell transcriptome analyses of preleukemic and leukemic cells (PLCs) and constructed the cellular and molecular transformation trajectory in a Myc-driven acute myeloid leukemia (AML) model in mice, which represented the transformation course in patients. We found that the Myc targets were gradually up-regulated along the trajectory. Among them were splicing factors, which showed stage-specific prognosis for AML patients. Furthermore, we dissected the detailed gene network of a tipping point for hematopoietic stem and progenitor cells (HSPCs) to generate initiating PLCs, which was characterized by dramatically increased splicing factors and unusual RNA velocity. In the late stage, PLCs acquired explosive heterogeneity through RNA alternative splicing. Among them, the Hsp90aa1hi subpopulation was conserved in both human and mouse AML and associated with poor prognosis. Exon 4 skipping of Tmem134 was identified in these cells. While the exon skipping product Tmem134ß promoted the cell cycle, full-length Tmem134α delayed tumorigenesis. Our study emphasized the critical roles of RNA splicing in the full process of leukemogenesis.
Assuntos
Leucemia Mieloide Aguda , Análise da Expressão Gênica de Célula Única , Humanos , Animais , Camundongos , Leucemia Mieloide Aguda/genética , Splicing de RNA/genética , RNA , Fatores de Processamento de RNA/genética , Transcriptoma/genéticaRESUMO
Alternative polyadenylation increases transcript diversities at the 3' end, regulating biological processes including cell differentiation, embryonic development and cancer progression. Here, we present a Bayesian method SCAPE, which enables de novo identification and quantification of polyadenylation (pA) sites at single-cell level by utilizing insert size information. We demonstrated its accuracy and robustness and identified 31 558 sites from 36 mouse organs, 43.8% (13 807) of which were novel. We illustrated that APA isoforms were associated with miRNAs binding and regulated in tissue-, cell type-and tumor-specific manners where no difference was found at gene expression level, providing an extra layer of information for cell clustering. Furthermore, we found genome-wide dynamic changes of APA usage during erythropoiesis and induced pluripotent stem cell (iPSC) differentiation, suggesting APA contributes to the functional flexibility and diversity of single cells. We expect SCAPE to aid the analyses of cellular dynamics and diversities in health and disease.
Assuntos
Células-Tronco Pluripotentes Induzidas , MicroRNAs , Regiões 3' não Traduzidas/genética , Animais , Teorema de Bayes , Diferenciação Celular/genética , Células-Tronco Pluripotentes Induzidas/metabolismo , Camundongos , MicroRNAs/genética , MicroRNAs/metabolismo , PoliadenilaçãoRESUMO
Extraction and determination of trace hazardous components from complex matrices continue to attract public attention. In this work, magnetic porous carbon (MPC) was prepared for efficient magnetic solid phase extraction (MSPE) of fluoroquinolone (FQ) antibiotics in food and water samples. To prepare the MPC, an Fe-based metal-organic framework (MIL-101(Fe)) was grown on a network of graphene oxide and multi-walled carbon nanotubes through a hydrothermal method, and then a carbonization process under a nitrogen atmosphere was carried out to obtain the MPC with high specific surface area and good magnetism. Four target FQs including ciprofloxacin (CIP), enrofloxacin (ENO), lomefloxacin (LOM) and ofloxacin (OFX) were enriched using the as-prepared MPC and determined by coupled high-performance liquid chromatography. Under the optimal conditions, the established MSPE-HPLC-UV detection method exhibited a linear range of 0.5-800 µg L-1 and detection limits of 0.11-0.18 µg L-1 with relative standard deviations (RSDs) of 0.5-4.8%. When applied in the determination of the above four FQs in real samples such as lake water, milk and pork, good recoveries between 85.2 and 103.7% were obtained, and the RSDs were less than 4.8%. This work indicates that the MPC material can be a good adsorption material and has good application prospects in antibiotics enrichment and/or removal from complex samples.
Assuntos
Estruturas Metalorgânicas , Nanotubos de Carbono , Estruturas Metalorgânicas/química , Porosidade , Fluoroquinolonas/análise , Fluoroquinolonas/química , Antibacterianos/análise , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Adsorção , Água , Fenômenos Magnéticos , Limite de DetecçãoRESUMO
Alternative splicing is widespread throughout eukaryotic genomes and greatly increases transcriptomic diversity. Many alternative isoforms have functional roles in developmental processes and are precisely temporally regulated. To facilitate the study of alternative splicing in a developmental context, we created MeDAS, a Metazoan Developmental Alternative Splicing database. MeDAS is an added-value resource that re-analyses publicly archived RNA-seq libraries to provide quantitative data on alternative splicing events as they vary across the time course of development. It has broad temporal and taxonomic scope and is intended to assist the user in identifying trends in alternative splicing throughout development. To create MeDAS, we re-analysed a curated set of 2232 Illumina polyA+ RNA-seq libraries that chart detailed time courses of embryonic and post-natal development across 18 species with a taxonomic range spanning the major metazoan lineages from Caenorhabditis elegans to human. MeDAS is freely available at https://das.chenlulab.com both as raw data tables and as an interactive browser allowing searches by species, tissue, or genomic feature (gene, transcript or exon ID and sequence). Results will provide details on alternative splicing events identified for the queried feature and can be visualised at the gene-, transcript- and exon-level as time courses of expression and inclusion levels, respectively.
Assuntos
Processamento Alternativo , Bases de Dados Genéticas , Regulação da Expressão Gênica no Desenvolvimento , Genoma , RNA Mensageiro/genética , Transcriptoma , Anfíbios/genética , Anfíbios/crescimento & desenvolvimento , Anfíbios/metabolismo , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/crescimento & desenvolvimento , Caenorhabditis elegans/metabolismo , Cefalocordados/genética , Cefalocordados/crescimento & desenvolvimento , Cefalocordados/metabolismo , Éxons , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Internet , Íntrons , Mamíferos/genética , Mamíferos/crescimento & desenvolvimento , Mamíferos/metabolismo , RNA Mensageiro/metabolismo , Répteis/genética , Répteis/crescimento & desenvolvimento , Répteis/metabolismo , Software , Urocordados/genética , Urocordados/crescimento & desenvolvimento , Urocordados/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/crescimento & desenvolvimento , Peixe-Zebra/metabolismoRESUMO
Epithelial ovarian cancer (EOC) is the most common and fatal subtype of ovarian malignancies, with no effective therapeutics available. Our previous studies have demonstrated extraordinary suppressive efficacy of enterolactone (ENL) on EOC. A chemotherapeutic agent, trabectedin (Trabe), is shown to be effective on ovarian cancer, especially when combined with other therapeutics, such as pegylated liposomal doxorubicin or oxaliplatin. Thrombospondin 1 (THBS1), a kind of matrix glycoprotein, plays important roles against cancer development through inhibiting angiogenesis but whether it is involved in the suppression of EOC by ENL or Trabe remains unknown. To test combined suppressive effects of ENL and Trabe on EOC and possible involvement of THBS1 in the anticancer activities of ENL and Trabe. The EOC cell line ES-2 was transfected with overexpressed THBS1 by lentivirus vector. We employed tube formation assay to evaluate the anti-angiogenesis activity of ENL and of its combined use with Trabe after THBS1 overexpression and established drug intervention and xenograft nude mouse cancer models to assess the in vivo effects of the hypothesized synergistic suppression between the agents and the involvement of THBS1. Mouse fecal samples were collected for 16S rDNA sequencing and microbiota analysis. We detected strong inhibitory activities of ENL and Trabe against the proliferation and migration of cancer cells and observed synergistic effects between ENL and Trabe in suppressing EOC. ENL and Trabe, given either separately or in combination, could suppress the tube formation capability of human microvascular endothelial cells, and this inhibitory effect became even stronger with THBS1 overexpression. In the ENL plus Trabe combination group, the expression of tissue inhibitor of metalloproteinases 3 and cluster of differentiation 36 was both upregulated, whereas matrix metalloproteinase 9, vascular endothelial growth factor, and cluster of differentiation 47 were all decreased. With the overexpression of THBS1, the results became even more pronounced. In animal experiments, combined use of ENL and Trabe showed superior inhibitory effects to either single agent and significantly suppressed tumor growth, and the overexpression of THBS1 further enhanced the anti-cancer activities of the drug combination group. ENL and Trabe synergistically suppress EOC and THBS1 could remarkably facilitate the synergistic anticancer effects of ENL and Trabe.
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Neoplasias Ovarianas , Trombospondina 1 , Animais , Camundongos , Humanos , Feminino , Carcinoma Epitelial do Ovário , Trabectedina/uso terapêutico , Trombospondina 1/uso terapêutico , Fator A de Crescimento do Endotélio Vascular , Células Endoteliais/metabolismo , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia , Linhagem Celular Tumoral , Proliferação de Células/genéticaRESUMO
A dual-mode electrochemical sensor was fabricated for carbendazim (CBD) detection. Biomass-derived carbon loaded gold nanoparticles (AuNPs/BC) were firstly coated on a glassy carbon electrode (GCE), and then molecularly imprinted polymer (MIP) of o-aminophenol was prepared on the resulting AuNPs/BC/GCE through electrochemical method in the presence of CBD. The AuNPs/BC had excellent conductivity, large surface and good electrocatalysis, while the imprinted film presented good recognition. Thus, the obtained MIP/AuNPs/BC/GCE exhibited sensitive current response to CBD. Furthermore, the sensor displayed good impedance response to CBD. Hence, a dual-mode detection platform for CBD was established. Under optimum conditions, the linear response ranges were as wide as 1.0 nM - 15 µM (by differential pulse voltammetry, DPV) and 1.0 nM - 10 µM (by electrochemical impedance spectroscopy, EIS), and the detection limits for these two methods were as low as 0.30 nM (S/N = 3) and 0.24 nM (S/N = 3), respectively. The sensor also had high selectivity, stability and reproducibility. The sensor was applied to detect CBD in spiked real samples, including cabbage, peach, apple and lake water, and the recoveries were 85.8-108% (by DPV) and 91.4-110% (by EIS); the relative standard deviations (RSD) were 3.4-5.3% (by DPV) and 3.7-5.1% (by EIS), respectively. The results were consistent with that obtained by high-performance liquid chromatography. Therefore, this sensor is a simple and effective tool for CBD detection, and it has good application potential.
Assuntos
Ouro , Nanopartículas Metálicas , Biomassa , Reprodutibilidade dos Testes , CarbonoRESUMO
Acute pancreatitis is a common gastrointestinal disease with increasing incidence worldwide. COVID-19 is a potentially life-threatening contagious disease spread throughout the world, caused by severe acute respiratory syndrome coronavirus 2. More severe forms of both diseases exhibit commonalities with dysregulated immune responses resulting in amplified inflammation and susceptibility to infection. Human leucocyte antigen (HLA)-DR, expressed on antigen-presenting cells, acts as an indicator of immune function. Research advances have highlighted the predictive values of monocytic HLA-DR (mHLA-DR) expression for disease severity and infectious complications in both acute pancreatitis and COVID-19 patients. While the regulatory mechanism of altered mHLA-DR expression remains unclear, HLA-DR-/low monocytic myeloid-derived suppressor cells are potent drivers of immunosuppression and poor outcomes in these diseases. Future studies with mHLA-DR-guided enrollment or targeted immunotherapy are warranted in more severe cases of patients with acute pancreatitis and COVID-19.
Assuntos
COVID-19 , Pancreatite , Humanos , Doença Aguda , Antígenos HLA-DR , Monócitos , ImunidadeRESUMO
OBJECTIVE: This study was aimed at comparing the outcomes of high-intensity focused ultrasound (HIFU) with those of uterine artery embolization (UAE) and traditional surgeries for treating symptomatic uterine fibroids. MATERIALS AND METHODS: We searched the following databases from their beginning to 5 November 2021: PubMed, Medline, Embase and Cochrane Library. RESULTS: Overall, 21 studies were included in this meta-analysis. The results revealed that HIFU had a higher re-intervention rate than UAE (relative risk [RR] = 4.06, 95% confidence interval [CI]: 2.47-6.69) and offered no significant advantages in reducing the symptom severity score (SSS) (mean difference [MD] = 17.01, 95% CI: 10.25-23.77) and improving the health-related quality of life (HRQoL) score (MD= -18.32, 95% CI: -24.87 to -11.78) in the treatment of symptomatic uterine fibroids. However, compared with UAE, HIFU may be associated with a higher pregnancy rate (RR = 17.44, 95% CI: 2.40-126.50) and may have a significant advantage in shortening pregnancy interval and preserving ovarian function. Moreover, upon comparing HIFU with traditional surgical treatments, the HIFU group showed significantly improved HRQoL score (MD = 2.25, 95% CI: 1.15-3.35), but the re-intervention rate (RR = 1.65, 95% CI: 0.59-4.57), pregnancy rate (RR = 1.01, 95% CI: 0.90-1.13), SSS and ovarian function did not significantly differ between the two groups. CONCLUSIONS: Although HIFU has relatively high re-intervention rate, it may offer a higher pregnancy rate and shorter pregnancy interval with little influence on ovarian function, thus making it an attractive option for treating symptomatic fibroids in young women who wish to plan a pregnancy in the future.
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Ablação por Ultrassom Focalizado de Alta Intensidade , Leiomioma , Neoplasias Uterinas , Feminino , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Humanos , Leiomioma/cirurgia , Leiomioma/terapia , Gravidez , Qualidade de Vida , Resultado do Tratamento , Neoplasias Uterinas/cirurgia , Neoplasias Uterinas/terapiaRESUMO
Herein a rapid and sensitive fluorometric bioanalysis platform for mercury(ii) (Hg2+) detection was innovatively developed using ultrathin two-dimensional MXenes (Ti3C2) as fluorescence quencher and Hg2+-induced exonuclease III (Exo III)-assisted target recycling strategy for efficient signal amplification. Initially, fluorophore-labeled single-stranded DNA (FAM-labeled probe) can be easily adsorbed onto the surface of ultrathin Ti3C2 nanosheets by hydrogen bonding and metal chelating interaction, and the fluorescence signal emitted by the FAM-labeled probe is quenched strongly owing to the fluorescence resonance energy transfer between the FAM and ultrathin Ti3C2 nanosheets. Upon sensing the target Hg2+, the protruding DNA fragment at the 3' end of hairpin will hybridize with primer (hairpin-Hg2+-primer), and then further digested by Exo III to produce a probe (nicker). The released target Hg2+ and primer continue to participate in the next recycling, resulting in more hairpin probes becoming nickers. The combination of a large number of nickers and FAM-probe resulted in a significant increase in the fluorescence signal of the system, which was attributed to the fact that the double helix DNA was more rigid and separated from the surface of the ultrathin Ti3C2 nanosheets. The obvious fluorescence signal change of the Ti3C2-based Exo III-assisted target recycling can be accurately monitored by fluorescence spectrometry, which is also proportional to the concentration of Hg2+. Under optimum operating conditions, the peak intensity (520 nm wavelength) of fluorescence increased with increasing Hg2+ within a wide dynamic working range from 0.05 nM to 50 nM (R2 = 0.9913) with a limit of detection down to 42.5 pM. The proposed strategy uses ultrathin MXenes as a platform for binding nucleic acids, which contributes to its potential in nucleic acid hybridization-based biosensing and/or nucleic acid signal amplification bio-applications.
Assuntos
Técnicas Biossensoriais , Mercúrio , Exodesoxirribonucleases , Limite de Detecção , Técnicas de Amplificação de Ácido Nucleico , TitânioRESUMO
Herein, we explore a general Cu2-x S nanocube template-assisted and reverse cation exchange-mediated growth strategy for fabricating hollow multinary metal sulfide. Unlike the traditional cation exchange method controlled by the metal sulfide constant, the introduction of tri-n-butylphosphine (TBP) can reverse cation exchange to give a series of hollow metal sulfides. A variety of hollow multinary metal sulfide cubic nanostructures has been demonstrated while preserving anisotropic shapes to the as-synthesized templates, including binary compounds (CdS, ZnS, Ag2 S, PbS, SnS), ternary compound (CuInS2 , Znx Cd1-x S), and quaternary compound (single-atom platinum anchored Znx Cd1-x S; Znx Cd1-x S-Pt1 ). Experimental and density functional theory (DFT) calculations show that the hollow metal sulfide semiconductors obtained could significantly improve the separation and migration of photogenerated electron-hole pairs. Owing to the efficient charge transfer, the Znx Cd1-x S-Pt1 exhibited outstanding photocatalytic performance of CO2 to CO, with the highest CO generation rate of 75.31â µmol h-1 .
RESUMO
BACKGROUND: There are over 200 million reported cases of malaria each year, and most children living in endemic areas will experience multiple episodes of clinical disease before puberty. We set out to understand how frequent clinical malaria, which elicits a strong inflammatory response, affects the immune system and whether these modifications are observable in the absence of detectable parasitaemia. METHODS: We used a multi-dimensional approach comprising whole blood transcriptomic, cellular and plasma cytokine analyses on a cohort of children living with endemic malaria, but uninfected at sampling, who had been under active surveillance for malaria for 8 years. Children were categorised into two groups depending on the cumulative number of episodes experienced: high (≥ 8) or low (< 5). RESULTS: We observe that multiple episodes of malaria are associated with modification of the immune system. Children who had experienced a large number of episodes demonstrated upregulation of interferon-inducible genes, a clear increase in circulating levels of the immunoregulatory cytokine IL-10 and enhanced activation of neutrophils, B cells and CD8+ T cells. CONCLUSION: Transcriptomic analysis together with cytokine and immune cell profiling of peripheral blood can robustly detect immune differences between children with different numbers of prior malaria episodes. Multiple episodes of malaria are associated with modification of the immune system in children. Such immune modifications may have implications for the initiation of subsequent immune responses and the induction of vaccine-mediated protection.
Assuntos
Doenças do Sistema Imunitário/imunologia , Malária/imunologia , Criança , Pré-Escolar , HumanosRESUMO
Proteases have been implicated in a variety of developmental processes during the malaria parasite lifecycle. In particular, invasion and egress of the parasite from the infected hepatocyte and erythrocyte, critically depend on protease activity. Although falcipain-1 was the first cysteine protease to be characterized in P. falciparum, its role in the lifecycle of the parasite has been the subject of some controversy. While an inhibitor of falcipain-1 blocked erythrocyte invasion by merozoites, two independent studies showed that falcipain-1 disruption did not affect growth of blood stage parasites. To shed light on the role of this protease over the entire Plasmodium lifecycle, we disrupted berghepain-1, its ortholog in the rodent parasite P. berghei. We found that this mutant parasite displays a pronounced delay in blood stage infection after inoculation of sporozoites. Experiments designed to pinpoint the defect of berghepain-1 knockout parasites found that it was not due to alterations in gliding motility, hepatocyte invasion or liver stage development and that injection of berghepain-1 knockout merosomes replicated the phenotype of delayed blood stage growth after sporozoite inoculation. We identified an additional role for berghepain-1 in preparing blood stage merozoites for infection of erythrocytes and observed that berghepain-1 knockout parasites exhibit a reticulocyte restriction, suggesting that berghepain-1 activity broadens the erythrocyte repertoire of the parasite. The lack of berghepain-1 expression resulted in a greater reduction in erythrocyte infectivity in hepatocyte-derived merozoites than it did in erythrocyte-derived merozoites. These observations indicate a role for berghepain-1 in processing ligands important for merozoite infectivity and provide evidence supporting the notion that hepatic and erythrocytic merozoites, though structurally similar, are not identical.
Assuntos
Cisteína Endopeptidases/metabolismo , Hepatócitos/metabolismo , Malária/metabolismo , Merozoítos/metabolismo , Plasmodium falciparum/metabolismo , Animais , Inibidores de Cisteína Proteinase/farmacologia , Eritrócitos/parasitologia , Hepatócitos/parasitologia , Fígado/metabolismo , Malária/parasitologia , Plasmodium falciparum/genética , Proteínas de Protozoários/metabolismoRESUMO
BACKGROUND: Parasite cytoadherence within the microvasculature of tissues and organs of infected individuals is implicated in the pathogenesis of several malaria syndromes. Multiple host receptors may mediate sequestration. The identity of the host receptor(s), or the parasite ligand(s) responsible for sequestration of Plasmodium species other than Plasmodium falciparum is largely unknown. The rodent malaria parasites may be useful to model interactions of parasite species, which lack the var genes with their respective hosts, as other multigene families are shared between the species. The role of the endothelial receptors ICAM-1 and CD36 in cytoadherence and in the development of pathology was investigated in a Plasmodium chabaudi infection in C57BL/6 mice lacking these receptors. The schizont membrane-associated cytoadherence (SMAC) protein of Plasmodium berghei has been shown to exhibit reduced CD36-associated cytoadherence in P. berghei ANKA-infected mice. METHODS: Parasite tissue sequestration and the development of acute stage pathology in P. chabaudi infections of mice lacking CD36 or ICAM-1, their respective wild type controls, and in infections with mutant P. chabaudi parasites lacking the smac gene were compared. Peripheral blood parasitaemia, red blood cell numbers and weight change were monitored throughout the courses of infection. Imaging of bioluminescent parasites in isolated tissues (spleen, lungs, liver, kidney and gut) was used to measure tissue parasite load. RESULTS: This study shows that neither the lack of CD36 nor the deletion of the smac gene from P. chabaudi significantly impacted on acute-stage pathology or parasite sequestration. By contrast, in the absence of ICAM-1, infected animals experience less anaemia and weight loss, reduced parasite accumulation in both spleen and liver and higher peripheral blood parasitaemia during acute stage malaria. The reduction in parasite tissue sequestration in infections of ICAM-1 null mice is maintained after mosquito transmission. CONCLUSIONS: These results indicate that ICAM-1-mediated cytoadherence is important in the P. chabaudi model of malaria and suggest that for rodent malarias, as for P. falciparum, there may be multiple host and parasite molecules involved in sequestration.
Assuntos
Antígenos CD36/genética , Molécula 1 de Adesão Intercelular/genética , Malária/parasitologia , Plasmodium chabaudi/fisiologia , Proteínas de Protozoários/genética , Animais , Antígenos CD36/metabolismo , Feminino , Molécula 1 de Adesão Intercelular/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Plasmodium chabaudi/genética , Proteínas de Protozoários/metabolismoRESUMO
The 10 Plasmodium 6-Cys proteins have critical roles throughout parasite development and are targets for antimalaria vaccination strategies. We analyzed the conserved 6-cysteine domain of this family and show that only the last 4 positionally conserved cysteine residues are diagnostic for this domain and identified 4 additional "6-Cys family-related" proteins. Two of these, sequestrin and B9, are critical to Plasmodium liver-stage development. RT-PCR and immunofluorescence assays show that B9 is translationally repressed in sporozoites and is expressed after hepatocyte invasion where it localizes to the parasite plasma membrane. Mutants lacking B9 expression in the rodent malaria parasites P. berghei and P. yoelii and the human parasite P. falciparum developmentally arrest in hepatocytes. P. berghei mutants arrest in the livers of BALB/c (100%) and C57BL6 mice (>99.9%), and in cultures of Huh7 human-hepatoma cell line. Similarly, P. falciparum mutants while fully infectious to primary human hepatocytes abort development 3 d after infection. This growth arrest is associated with a compromised parasitophorous vacuole membrane a phenotype similar to, but distinct from, mutants lacking the 6-Cys sporozoite proteins P52 and P36. Our results show that 6-Cys proteins have critical but distinct roles in establishment and maintenance of a parasitophorous vacuole and subsequent liver-stage development.
Assuntos
Regulação da Expressão Gênica , Hepatócitos/parasitologia , Plasmodium/metabolismo , Proteínas de Protozoários/metabolismo , Animais , Linhagem Celular , Biologia Computacional , Cisteína/metabolismo , Feminino , Genótipo , Proteínas de Fluorescência Verde/metabolismo , Malária/parasitologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Mutação , Fenótipo , Plasmodium berghei/metabolismo , Plasmodium falciparum/metabolismo , Plasmodium yoelii/metabolismo , Biossíntese de Proteínas , Esporozoítos/crescimento & desenvolvimentoRESUMO
Model antigens are frequently introduced into pathogens to study determinants that influence T-cell responses to infections. To address whether an antigen's subcellular location influences the nature and magnitude of antigen-specific T-cell responses, we generated Plasmodium berghei parasites expressing the model antigen ovalbumin (OVA) either in the parasite cytoplasm or on the parasitophorous vacuole membrane (PVM). For cytosolic expression, OVA alone or conjugated to mCherry was expressed from a strong constitutive promoter (OVAhsp70 or OVA::mCherryhsp70); for PVM expression, OVA was fused to HEP17/EXP1 (OVA::Hep17hep17). Unexpectedly, OVA expression in OVAhsp70 parasites was very low, but when OVA was fused to mCherry (OVA::mCherryhsp70), it was highly expressed. OVA expression in OVA::Hep17hep17 parasites was strong but significantly less than that in OVA::mCherryhsp70 parasites. These transgenic parasites were used to examine the effects of antigen subcellular location and expression level on the development of T-cell responses during blood-stage infections. While all OVA-expressing parasites induced activation and proliferation of OVA-specific CD8(+) T cells (OT-I) and CD4(+) T cells (OT-II), the level of activation varied: OVA::Hep17hep17 parasites induced significantly stronger splenic and intracerebral OT-I and OT-II responses than those of OVA::mCherryhsp70 parasites, but OVA::mCherryhsp70 parasites promoted stronger OT-I and OT-II responses than those of OVAhsp70 parasites. Despite lower OVA expression levels, OVA::Hep17hep17 parasites induced stronger T-cell responses than those of OVA::mCherryhsp70 parasites. These results indicate that unconjugated cytosolic OVA is not stably expressed in Plasmodium parasites and, importantly, that its cellular location and expression level influence both the induction and magnitude of parasite-specific T-cell responses. These parasites represent useful tools for studying the development and function of antigen-specific T-cell responses during malaria infection.
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Regulação da Expressão Gênica/fisiologia , Malária/parasitologia , Ovalbumina/metabolismo , Plasmodium berghei/metabolismo , Transporte Proteico/fisiologia , Animais , Feminino , Malária/sangue , Camundongos , Organismos Geneticamente Modificados , Ovalbumina/genética , Plasmodium berghei/genética , Baço/citologia , Linfócitos T/fisiologiaRESUMO
Rhomboid-like proteases cleave membrane-anchored proteins within their transmembrane domains. In apicomplexan parasites substrates include molecules that function in parasite motility and host cell invasion. While two Plasmodium rhomboids, ROM1 and ROM4, have been examined, the roles of the remaining six rhomboids during the malaria parasite's life cycle are unknown. We present systematic gene deletion analyses of all eight Plasmodium rhomboid-like proteins as a means to discover stage-specific phenotypes and potential functions in the rodent malaria model, P. berghei. Four rhomboids (ROM4, 6, 7 and 8) are refractory to gene deletion, suggesting an essential role during asexual blood stage development. In contrast ROM1, 3, 9 and 10 were dispensable for blood stage development and exhibited no, subtle or severe defects in mosquito or liver development. Parasites lacking ROM9 and ROM10 showed no major phenotypic defects. Parasites lacking ROM1 presented a delay in blood stage patency following liver infection, but in contrast to a previous study blood stage parasites had similar growth and virulence characteristics as wild type parasites. Parasites lacking ROM3 in mosquitoes readily established oocysts but failed to produce sporozoites. ROM3 is the first apicomplexan rhomboid identified to play a vital role in sporogony.
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Peptídeo Hidrolases/metabolismo , Plasmodium berghei/enzimologia , Plasmodium berghei/fisiologia , Proteínas de Protozoários/metabolismo , Animais , Sangue/parasitologia , Culicidae/parasitologia , Feminino , Deleção de Genes , Estágios do Ciclo de Vida , Fígado/parasitologia , Malária/parasitologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Peptídeo Hidrolases/genética , Plasmodium berghei/genética , Plasmodium berghei/patogenicidade , Proteínas de Protozoários/genética , Esporozoítos/fisiologia , VirulênciaRESUMO
Malaria-associated acute respiratory distress syndrome (MA-ARDS) is a deadly complication of malaria, and its pathophysiology is insufficiently understood. Both in humans and in murine models, MA-ARDS is characterized by marked pulmonary inflammation. We investigated the role of hemozoin in MA-ARDS in C57Bl/6 mice infected with Plasmodium berghei NK65, P. berghei ANKA, and P. chabaudi AS. By quantifying hemozoin in the lungs and measuring the disease parameters of MA-ARDS, we demonstrated a highly significant correlation between pulmonary hemozoin concentrations, lung weights, and alveolar edema. Histological analysis of the lungs demonstrated that hemozoin is localized in phagocytes and infected erythrocytes, and only occasionally in granulocytes. Species-specific differences in hemozoin production, as measured among individual schizonts, were associated with variations in pulmonary pathogenicity. Furthermore, both pulmonary hemozoin and lung pathology were correlated with the number of infiltrating inflammatory cells, an increased pulmonary expression of cytokines, chemokines, and enzymes, and concentrations of alveolar vascular endothelial growth factor. The causal relationship between hemozoin and inflammation was investigated by injecting P. falciparum-derived hemozoin intravenously into malaria-free mice. Hemozoin potently induced the pulmonary expression of proinflammatory chemokines (interferon-γ inducible protein-10/CXC-chemokine ligand (CXCL)10, monocyte chemotactic protein-1/CC-chemokine ligand 2, and keratinocyte-derived chemokine/CXCL1), cytokines (IL-1ß, IL-6, IL-10, TNF, and transforming growth factor-ß), and other inflammatory mediators (inducible nitric oxide synthase, heme oxygenase-1, nicotinamide adenine dinucleotide phosphate- oxidase-2, and intercellular adhesion molecule-1). Thus, hemozoin correlates with MA-ARDS and induces pulmonary inflammation.
Assuntos
Hemeproteínas/metabolismo , Malária/metabolismo , Plasmodium berghei/metabolismo , Plasmodium chabaudi/metabolismo , Pneumonia/parasitologia , Síndrome do Desconforto Respiratório/metabolismo , Animais , Líquido da Lavagem Broncoalveolar/química , Contagem de Linfócito CD4 , Quimiocina CCL2/genética , Quimiocina CCL2/metabolismo , Eritrócitos/metabolismo , Eritrócitos/parasitologia , Expressão Gênica , Hemeproteínas/fisiologia , Interações Hospedeiro-Parasita , Humanos , Interleucina-10/genética , Interleucina-10/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Pulmão/parasitologia , Macrófagos/metabolismo , Macrófagos/parasitologia , Malária/complicações , Malária/parasitologia , Camundongos , Camundongos Endogâmicos C57BL , Tamanho do Órgão , Plasmodium berghei/imunologia , Plasmodium berghei/fisiologia , Plasmodium chabaudi/imunologia , Plasmodium chabaudi/fisiologia , Pneumonia/imunologia , Pneumonia/metabolismo , Síndrome do Desconforto Respiratório/etiologia , Esquizontes/imunologia , Esquizontes/metabolismo , Esquizontes/fisiologia , Especificidade da Espécie , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Coatings are considered to play a crucial role in solid-phase microextraction (SPME). In this work, a novel coating named ZIF-67/[HOEMIM]BF4 was fabricated through in situ potentiostatic electrodeposition in methanol solutions containing ZIF-67 precursors and 1-(2'-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([HOEMIM]BF4). Compared with the traditional solvothermal method, this method reduced the synthesis time and enabled ZIF-67 to grow directly on the surface of stainless-steel wire, effectively simplifying the preparation process and improving the coating reproducibility. Owing to the inherent characteristics such as high porosity and high thermal and mechanical stability, and the impressive morphological regulation and extraction function of [HOEMIM]BF4, the developed coating exhibited a prolonged service life and a better extraction capacity for trace polycyclic aromatic hydrocarbons (PAHs) compared to single ZIF-67 and commercial fibers. Under the optimal conditions, the linear range of the ZIF-67/[HOEMIM]BF4-based SPME-GC method was 0.01-500 µg L-1, and the detection limit was 0.27-5.2 ng L-1. When applied in the determination of PAHs in a real water sample, recoveries between 85.6-117.3% were obtained, indicating the potential of ZIF-67/[HOEMIM]BF4 in the high efficiency SPME and GC analysis of PAHs.
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Background: This study evaluated the cost-effectiveness of elacestrant (ELA) and standard-of-care (SOC) as second-/third-line treatment for pretreated estrogen receptor (ER)- positive/human epidermal growth factor receptor 2 (HER2)-negative advanced or metastatic breast cancer (A/MBC) in the US. Methods: The 3 health states partitioned survival model (PSM) was conducted from the perspective of the US third-party payers. The time horizon for the model lasted 10 years. Effectiveness and safety data were derived from the EMERALD trial (NCT03778931). Costs were derived from the pricing files of Medicare and Medicaid Services, and utility values were derived from published studies. One-way sensitivity analysis as well as probabilistic sensitivity analysis were performed to observe model stability. Result: ELA led to an incremental cost-effectiveness ratio (ICER) of $8,672,360/quality-adjusted life year (QALY) gained compared with SOC in the overall population and $2,900,560/QALY gained compared with fulvestrant (FUL) in the ESR1(estrogen receptor 1) mutation subgroup. The two ICERs of ELA were significantly higher than the willingness-to-pay (WTP) threshold values of $150,000/QALY. Conclusions: ELA was not cost-effective for the second-/third-line treatment of patients with ER+/HER2-A/MBC compared with SOC in the US.
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Single-piece flexible supercapacitors (FSCs) have light and ultrathin superiorities, thereby having great potential in portable/wearable electronics. However, all the available single-piece FSCs are fabricated by in situ growth routes, which are incompatible with large-scale technology. This work designs a carboxymethyl cellulose/phytic acid/polyaniline ink, incorporating electrode with electrolyte active compositions. Based on the electrode/electrolyte active ink, a double-face print technique on mixed cellulose ester and nylon membranes to fabricate single-piece membrane-FSCs, where both sides of membranes can be utilized well, is proposed. Consequently, one FSC is measured to be only ≈0.785 cm2 in area, ≈0.021 g in weight, and ≈200 µm in thickness, while it has exceptional areal and volumetric capacitances up to 757 mF cm-2 and 37.8 F cm-3 , respectively, based on the entire device. It also exhibits high flexibility with a capacitance retention of 98% after 2000 bend cycles from 0° to 180°. The state-of-the-art FSCs are expected to have exciting prospects in portable/wearable electronics, smart reading, and flexible displays. The preparation strategy renders the massive production of large-area and mini-size arrayed FSCs, and also the "do-it-yourself" or homemade preparation, which adds more interest and designability for general users.