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Feline parvovirus (FPV) infection is highly fatal in felines. NS1, which is a key nonstructural protein of FPV, can inhibit host innate immunity and promote viral replication, which is the main reason for the severe pathogenicity of FPV. However, the mechanism by which the NS1 protein disrupts host immunity and regulates viral replication is still unclear. Here, we identified an FPV M1 strain that is regulated by the NS1 protein and has more pronounced suppression of innate immunity, resulting in robust replication. We found that the neutralization titer of the FPV M1 strain was significantly lower than that of the other strains. Moreover, FPV M1 had powerful replication ability, and the FPV M1-NS1 protein had heightened efficacy in repressing interferon-stimulated genes (ISGs) expression. Subsequently, we constructed an FPV reverse genetic system, which confirmed that the N588 residue of FPV M1-NS1 protein is a key amino acid that bolsters viral proliferation. Recombinant virus containing N588 also had stronger ability to inhibit ISGs, and lower ISGs levels promoted viral replication and reduced the neutralization titer of the positive control serum. Finally, we confirmed that the difference in viral replication was abolished in type I IFN receptor knockout cell lines. In conclusion, our results demonstrate that the N588 residue of the NS1 protein is a critical amino acid that promotes viral proliferation by increasing the inhibition of ISGs expression. These insights provide a reference for studying the relationship between parvovirus-mediated inhibition of host innate immunity and viral replication while facilitating improved FPV vaccine production.IMPORTANCEFPV infection is a viral infectious disease with the highest mortality rate in felines. A universal feature of parvovirus is its ability to inhibit host innate immunity, and its ability to suppress innate immunity is mainly accomplished by the NS1 protein. In the present study, FPV was used as a viral model to explore the mechanism by which the NS1 protein inhibits innate immunity and regulates viral replication. Studies have shown that the FPV-NS1 protein containing the N588 residue strongly inhibits the expression of host ISGs, thereby increasing the viral proliferation titer. In addition, the presence of the N588 residue can increase the proliferation titer of the strain 5- to 10-fold without affecting its virulence and immunogenicity. In conclusion, our findings provide new insights and guidance for studying the mechanisms by which parvoviruses suppress innate immunity and for developing high-yielding FPV vaccines.
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Vírus da Panleucopenia Felina , Proteínas não Estruturais Virais , Replicação Viral , Animais , Gatos , Linhagem Celular , Vírus da Panleucopenia Felina/genética , Vírus da Panleucopenia Felina/imunologia , Imunidade Inata , Mutação , Infecções por Parvoviridae/virologia , Infecções por Parvoviridae/imunologia , Proteínas não Estruturais Virais/genética , Proteínas não Estruturais Virais/metabolismo , Proteínas não Estruturais Virais/imunologiaRESUMO
There is still controversy about whether to continue antiviral therapy (AVT) after delivery, especially for pregnant women in the immune tolerance (IT) phase. In this study, a retrospective cohort study was conducted to explore the relationship between hepatitis B e antigen (HBeAg) decline rate (%) from mid-pregnancy to delivery and HBeAg seroconversion postpartum among patients using nucleos(t)ide analogs (NAs) to prevent mother-to-child transmission (MTCT), with the goal of identifying the ideal candidates for postpartum AVT continuation. This retrospective cohort study included 151 postpartum women. Univariate and multivariable logistic regression analyses were conducted to assess the association between the HBeAg decline rate (%) from mid-pregnancy to delivery and HBeAg seroconversion postpartum. Receiver operating characteristic (ROC) analysis was utilized to evaluate the predictive capacity of the HBeAg decline rate (%) and determine the optimal cut-off point. The univariate analysis revealed a significant association between the HBeAg decline rate (%) and HBeAg seroconversion postpartum (OR 1.068, 95% CI: 1.034-1.103, p < .001). In the multivariate regression analysis, adjusting for age, hepatitis B surface antigen (HBsAg) titre (log10 IU/mL) at mid-pregnancy, HBeAg titre (log10 S/CO) at mid-pregnancy, and hepatitis B virus (HBV) DNA load decline rate (%) from mid-pregnancy to delivery, the HBeAg decline rate(%) remained significantly associated with HBeAg seroconversion postpartum (OR 1.050, 95% CI: 1.015-1.093, p = .009). Then HBeAg decline rate (%) was treated as a categorical variable (tertiles) for sensitivity analysis. In the three distinct models, taking Tertile1 as a reference, women in Tertile3 still had a 4.201-fold (OR 4.201, 95% CI: 1.382-12.773, p = .011) higher risk of developing HBeAg seroconversion (p for trend <.05) after adjusting above covariates. The area under the curve (AUC) was 0.723 (95% CI: 0.627-0.819). The optimal cut-off value was 5.43%, with a sensitivity of 0.561, specificity of 0.791, and Youden's index of 0.352.A higher HBeAg decline rate (%) from mid-pregnancy to delivery independently correlated with an increased risk of HBeAg seroconversion postpartum. This decline rate can serve as a valuable clinical indicator for predicting HBeAg seroconversion.
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Antígenos E da Hepatite B , Período Pós-Parto , Complicações Infecciosas na Gravidez , Soroconversão , Humanos , Feminino , Gravidez , Antígenos E da Hepatite B/sangue , Adulto , Estudos Retrospectivos , Complicações Infecciosas na Gravidez/imunologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Antivirais/uso terapêutico , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/imunologia , Adulto Jovem , Curva ROC , Hepatite B/imunologia , Vírus da Hepatite B/imunologiaRESUMO
Patients diagnosed with non-small cell lung cancer (NSCLC) have a limited lifespan and exhibit poor immunotherapy outcomes. M1 macrophages have been found to be essential for antitumor immunity. This study aims to develop an immunotherapy response evaluation model for NSCLC patients based on transcription. RNA sequencing profiles of 254 advanced-stage NSCLC patients treated with immunotherapy are downloaded from the POPLAR and OAK projects. Immune cell infiltration in NSCLC patients is examined, and thereafter, different coexpressed genes are identified. Next, the impact of M1 macrophage-related genes on the prognosis of NSCLC patients is investigated. Six M1 macrophage coexpressed genes, namely, NKX2-1, CD8A , SFTA3, IL2RB, IDO1, and CXCL9, exhibit a strong association with the prognosis of NSCLC and serve as effective predictors for immunotherapy response. A response model is constructed using a Cox regression model and Lasso Cox regression analysis. The M1 genes are validated in our TD-FOREKNOW NSCLC clinical trial by RT-qPCR. The response model shows excellent immunotherapy response prediction and prognosis evaluation value in advanced-stage NSCLC. This model can effectively predict advanced NSCLC prognosis and aid in identifying patients who could benefit from customized immunotherapy as well as sensitive drugs.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Populus , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/terapia , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/terapia , Imunoterapia , Macrófagos , Microambiente TumoralRESUMO
Arsenic, a neurotoxic metalloid, poses significant health risks. However, ellagic acid, renowned for its antioxidant properties, has shown potential in neuroprotection. This study aimed to investigate the neuroprotective effects of ellagic acid against arsenic-induced neuronal ferroptosis and cognitive impairment and elucidate the underlying mechanisms. Using an arsenic-exposed Wistar rat model and an arsenic-induced HT22 cells model, we assessed cognitive ability, measured serum and brain arsenic levels, and evaluated pathological damage through histological analysis and transmission electron microscopy. Additionally, we examined oxidative stress and iron ion levels using GSH, MDA, ROS and tissue iron biochemical kits, and analyzed the expression of ferroptosis-related markers using western blot and qRT-PCR. Our results revealed that arsenic exposure increased both serum and brain arsenic levels, resulting in hippocampal pathological damage and subsequent decline in learning and memory abilities. Arsenic-induced neuronal ferroptosis was mediated by the inhibition of the xCT/GSH/GPX4/Nrf2 signaling axis and disruption of iron metabolism. Notably, ellagic acid intervention effectively reduced serum and brain arsenic levels, ameliorated neuronal damage, and improved oxidative stress, ferroptosis, and cognitive impairment. These beneficial effects were associated with the activation of the Nrf2/Keap1 signaling pathway, upregulation of GPX4 expression, and enhanced iron ion excretion. In conclusion, ellagic acid demonstrates promising neuroprotective effects against arsenic-induced neurotoxicity by mitigating neuronal ferroptosis and cognitive impairment.
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Fluoride exposure has been implicated as a potential risk factor for hypertension, but the underlying mechanisms remain unclear. This study investigated the role of the RhoA/ROCK signaling pathway in fluoride-induced hypertension. Male Wistar rats were divided into different groups and exposed to varying concentrations of sodium fluoride (NaF) or sodium chloride (NaCl) via drinking water. The rats' blood pressure was measured, and their aortic tissue was utilized for high-throughput sequencing analysis. Additionally, rat and A7r5 cell models were established using NaF and/or Fasudil. The study evaluated the effects of fluoride exposure on blood pressure, pathological changes in the aorta, as well as the protein/mRNA expression levels of phenotypic transformation indicators (a-SMA, calp, OPN) in vascular smooth muscle cells (VSMCs), along with the RhoA/ROCK signaling pathway (RhoA, ROCK1, ROCK2, MLC/p-MLC). The results demonstrated that fluoride exposure in rats led to increased blood pressure. High-throughput sequencing analysis revealed differential gene expression associated with vascular smooth muscle contraction, with the RhoA/ROCK signaling pathway emerging as a key regulator. Pathological changes in the rat aorta, such as elastic membrane rupture and collagen fiber deposition, were observed following NaF exposure. However, fasudil, a ROCK inhibitor, mitigated these pathological changes. Both in vitro and in vivo models confirmed the activation of the RhoA/ROCK signaling pathway and the phenotypic transformation of VSMCs from a contractile to a synthetic state upon fluoride exposure. Fasudil effectively inhibited the activities of ROCK1 and ROCK2 and attenuated the phenotypic transformation of VSMCs. In conclusion, fluoride has the potential to induce hypertension through the activation of the RhoA/ROCK signaling pathway and phenotypic changes in vascular smooth muscle cells. These results provide new insights into the mechanism of fluoride-induced hypertension.
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Hipertensão , Músculo Liso Vascular , Ratos Wistar , Transdução de Sinais , Quinases Associadas a rho , Animais , Quinases Associadas a rho/metabolismo , Masculino , Hipertensão/induzido quimicamente , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/patologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Proteína rhoA de Ligação ao GTP/metabolismo , Fluoreto de Sódio/toxicidade , Miócitos de Músculo Liso/efeitos dos fármacos , Miócitos de Músculo Liso/patologia , Fenótipo , Pressão Sanguínea/efeitos dos fármacos , Fluoretos/toxicidade , Proteínas rho de Ligação ao GTPRESUMO
The rapid global emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused serious health problems, highlighting the urgent need for antiviral drugs. The viral main protease (Mpro) plays an important role in viral replication and thus remains the target of choice for the prevention or treatment of several viral diseases due to high sequence and structural conservation. Prolonged use of viral protease inhibitors can lead to the development of mutants resistant to those inhibitors and to many of the available antiviral drugs. Here, we used feline infectious peritonitis virus (FIPV) as a model to investigate its development of resistance under pressure from the Mpro inhibitor GC376. Passage of wild-type (WT) FIPV in the presence of GC376 selected for a mutation in the nsp12 region where Mpro cleaves the substrate between nsp12 and nsp13. This mutation confers up to 3-fold resistance to GC376 and nirmatrelvir, as determined by EC50 assay. In vitro biochemical and cellular experiments confirmed that FIPV adapts to the stress of GC376 by mutating the nsp12 and nsp13 hydrolysis site to facilitate cleavage by Mpro and release to mediate replication and transcription. Finally, we demonstrate that GC376 cannot treat FIP-resistant mutants that cause FIP in animals. Taken together, these results suggest that Mpro affects the replication of coronaviruses (CoVs) and the drug resistance to GC376 by regulating the amount of RdRp from a distant site. These findings provide further support for the use of an antiviral drug combination as a broad-spectrum therapy to protect against contemporary and emerging CoVs. IMPORTANCE CoVs cause serious human infections, and antiviral drugs are currently approved to treat these infections. The development of protease-targeting therapeutics for CoV infection is hindered by resistance mutations. Therefore, we should pay attention to its resistance to antiviral drugs. Here, we identified possible mutations that lead to relapse after clinical treatment of FIP. One amino acid substitution in the nsp12 polymerase at the Mpro cleavage site provided low-level resistance to GC376 after selection exposure to the GC376 parental nucleoside. Resistance mutations enhanced FIPV viral fitness in vitro and attenuated the therapeutic effect of GC376 in an animal model of FIPV infection. Our research explains the evolutionary characteristics of coronaviruses under antiviral drugs, which is helpful for a more comprehensive understanding of the molecular basis of virus resistance and provides important basic data for the effective prevention and control of CoVs.
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Antivirais , Proteases 3C de Coronavírus , Coronavirus Felino , Farmacorresistência Viral , Mutação , Inibidores de Proteases , Animais , Antivirais/farmacologia , Gatos/virologia , Proteases 3C de Coronavírus/antagonistas & inibidores , Proteases 3C de Coronavírus/genética , Proteases 3C de Coronavírus/metabolismo , Coronavirus Felino/efeitos dos fármacos , Coronavirus Felino/enzimologia , Coronavirus Felino/genética , Farmacorresistência Viral/genética , Inibidores de Proteases/farmacologiaRESUMO
Feline infectious peritonitis virus (FIPV) is the etiologic agent of feline infectious peritonitis (FIP) and causes fatal disease in cats of almost all ages. Currently, there are no clinically approved drugs or effective vaccines for FIP. Furthermore, the pathogenesis of FIP is still not fully understood. There is an urgent need for an effective infection model of feline infectious peritonitis induced by FIPV. Here, we constructed a field type I FIPV full-length cDNA clone, pBAC-QS, corresponding to the isolated FIPV QS. By replacing the FIPV QS spike gene with the commercially available type II FIPV 79-1146 (79-1146_CA) spike gene, we established and rescued a recombinant virus, designated rQS-79. Moreover, we constructed 79-1146_CA infectious full-length cDNA pBAC-79-1146_CA, corresponding to recombinant feline coronavirus (FCoV) 79-1146_CA (r79-1146_CA). In animal experiments with 1- to 2-year-old adult cats orally infected with the recombinant virus, rQS-79 induced typical FIP signs and 100% mortality. In contrast to cats infected with rQS-79, cats infected with 79-1146_CA did not show obvious signs. Furthermore, by rechallenging rQS-79 in surviving cats previously infected with 79-1146_CA, we found that there was no protection against rQS-79 with different titers of neutralizing antibodies. However, high titers of neutralizing antibodies may help prolong the cat survival time. Overall, we report the first reverse genetics of virulent recombinant FCoV (causing 100% mortality in adult cats) and attenuated FCoV (causing no mortality in adult cats), which will be powerful tools to study pathogenesis, antiviral drugs, and vaccines for FCoV. IMPORTANCE Tissue- or cell culture-adapted feline infectious peritonitis virus (FIPV) usually loses pathogenicity. To develop a highly virulent FIPV, we constructed a field isolate type I FIPV full-length clone with the spike gene replaced by the 79-1146 spike gene, corresponding to a virus named rQS-79, which induces high mortality in adult cats. rQS-79 represents the first described reverse genetics system for highly pathogenic FCoV. By further constructing the cell culture-adapted FCoV 79-1146_CA, we obtained infectious clones of virulent and attenuated FCoV. By in vitro and in vivo experiments, we established a model that can serve to study the pathogenic mechanisms of FIPV. Importantly, the wild-type FIPV replicase skeleton of serotype I will greatly facilitate the screening of antiviral drugs, both in vivo and in vitro.
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Coronavirus Felino/genética , Coronavirus Felino/patogenicidade , Peritonite Infecciosa Felina , Adenosina/análogos & derivados , Adenosina/uso terapêutico , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/sangue , Anticorpos Antivirais/imunologia , Antivirais/uso terapêutico , Gatos , Coronavirus Felino/classificação , Coronavirus Felino/imunologia , DNA Complementar , Peritonite Infecciosa Felina/tratamento farmacológico , Peritonite Infecciosa Felina/imunologia , Peritonite Infecciosa Felina/patologia , Peritonite Infecciosa Felina/virologia , Genoma Viral , Rim/patologia , Genética Reversa , Sorogrupo , Glicoproteína da Espícula de Coronavírus/genética , VirulênciaRESUMO
Porcine deltacoronavirus (PDCoV) and porcine epidemic diarrhea virus (PEDV) have often been detected simultaneously in piglets with coronavirus diarrhea. However, the intestinal immune response to the interaction between circulating PDCoV and PEDV is unknown. Therefore, this study was conducted to investigate the intestinal immunity of neonatal piglets that were exposed first to PDCoV and then to PEDV. The amounts and distribution of CD3+ T lymphocytes, B lymphocytes, and goblet cells (GCs) in the small intestine were analyzed by immunohistochemistry and periodic acid-Schiff staining, respectively. The expression levels of pattern recognition receptors and downstream mediator cytokines were analyzed by qPCR and ELISA. The results showed that the numbers of GCs, CD3+ T lymphocytes, and B lymphocytes in the duodenum and jejunum of the PDCoV + PEDV coinoculated piglets were increased compared with those of piglets inoculated with PEDV alone. The piglets in the PDCoV + PEDV group had significantly upregulated IFN-α and IFN-λ1 compared with the PEDV single-inoculated piglets. These results suggest that PDCoV + PEDV-coinfected piglets can activate intestinal antiviral immunity more strongly than piglets infected with PEDV alone, which provides new insight into the pathogenesis mechanism of swine enteric coronavirus coinfection that may be used for vaccination in the future.
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Infecções por Coronavirus , Coronavirus , Vírus da Diarreia Epidêmica Suína , Doenças dos Suínos , Animais , Infecções por Coronavirus/epidemiologia , Deltacoronavirus , Diarreia/veterinária , Vírus da Diarreia Epidêmica Suína/fisiologia , SuínosRESUMO
The novel polychloromethylation/acyloxylation of 1,6-enynes with chloroalkanes and diacyl peroxides through dual-role designs has been developed to prepare 2-pyrrolidinone derivatives with polychloromethyl units with the use of an inexpensive copper salt under mild conditions. This strategy includes two dual-role designs, not only improving atomic utilization but also allowing a cleaner process. The wide substrate scope and simple reaction conditions demonstrate the practicability of this protocol.
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The direct use structurally simple ketones as α-ketone radical sources for α-C(sp3)-H functionalization is a sustainable and powerful approach for constructing complex and multifunctional chemical scaffolds with diverse applications. The reactions of α-ketone radicals with alkenes, alkynes, enynes, imides, and imidazo[1,2-a]pyridines have broadened the structural diversity and complexity of ketones. Through chosen illustrative examples, we outline the recent progress in the development of methods that enable the radical α-C(sp3)-H functionalization of ketones, with an emphasis on radical initiation systems and possible mechanisms of the transformations. The application of these strategies is illustrated by the synthesis of several biologically active molecules and drug molecules. Further subdivision is based on substrate type and reaction type.
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In this work, two new fluorescence chemosensors 2-(4-(1,2,2-triphenylvinyl)phenoxy) acetic acid (TPE-COOH) and 2,2'-(((1,2-diphenylethane-1,2-diyl)bis(4,1-phenylene))bis(oxy))diacetic acid (TPE-(COOH)2) were synthesized and applied for the facile detection of physiological phosphates. Due to the aggregation-induced emission (AIE) character, the emission can be turned on after label free interaction with polyethyleneimine (PEI). When the physiological phosphates were introduced to the system, the AIEgens/PEI complex was dissociated due to stronger electrostatic interaction between PEI and phosphates, which resulted in the significant fluorescence quenching of AIEgens. As the four kinds of phosphates cytidine-5'-diphosphate disodium salt (CDP), adenosine-5 (ADP), sodium pyrophosphate (PPi) and guanosine-5'-diphosphate disodium salt (GDP) had different interaction with PEI, also the TPE-COOH and TPE-(COOH)2 had different interaction with PEI, the fluorescence quenching effect was distinct for four phosphates. The unique pattern of fluorescence variations was differentiated by chemometric methods including principal component analysis and linear discriminant analysis. The robustness of the sensor array was proved by discrimination of four kinds of phosphates in serum samples with different concentrations, and the discrimination capacity was not influenced in complicated samples Graphical abstract.
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Acetatos/química , Corantes Fluorescentes/química , Fosfatos/análise , Acetatos/síntese química , Corantes Fluorescentes/síntese químicaRESUMO
A molecularly imprinted polymer (MIP) was fabricated for selective recognition of the highly persistent pollutant perfluorooctane sulfonate (PFOS). The MIP was prepared from chitosan and doped with fluorescent carbon quantum dots (CQDs). It was characterized by fluorescence spectrophotometry, scanning electron microscopy, and Fourier transform infrared spectroscopy. The fluorescence of the CQDs, best measured at excitation/emission wavelengths of 350/460 nm, is enhanced by PFOS, and the effect is much stronger for the MIP than for the nonimprinted polymer (NIP). The imprinting factor is 2.75. The method has good specificity over sodium dodecyl sulfate (SDS), perfluorooctanoic acid (PFOA), sodium dodecyl sulfonate (SDS'), sodium dodecyl benzene sulfonate (SDBS), perfluorooctanesulfonyl fluoride (POSF), perfluorobutane sulfonate (PFBS) and 1-octanesulfonic acid sodium (OSA). Fluorescence increases linearly in the 20-200 pg·L-1 POSF concentration range in aqueous solution. The method was applied to the determination of PFOS in spiked serum and urine samples. The limits of detection are 66 and 85 pg·L-1 for serum and urine samples respectively. The recoveries ranged from to 81-98%, with relative standard deviations in the range of 1.8-8.2%. Compared with LC-MS/MS, this assay is more convenient since the material can be prepared flexibly and the method can be applied on-site. Graphical abstract Schematic of the fabrication of a molecularly imprinted chitosan hydrogel doped with CQDs for selective fluorometric determination of PFOS. a. The photo of chitosan hydrogel. b, c, d, e represents the hydrogel observed under UV lamp. b', c', d', e' represents the inner structure of hydrogel bead.
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Cardiomyopathy (CM) is an intrinsic weakening of myocardium with contractile dysfunction and congestive heart failure (CHF). CHF has been postulated to result from decreased mitochondrial energy production and oxidative stress. Effects of decreased mitochondrial oxygen consumption also can accelerate with aging. We previously showed DNA methylation changes in human hearts with CM. This was associated with mitochondrial DNA depletion, being another molecular marker of CM. We examined the relationship between mitochondrial dysfunction and cardiac epigenetic DNA methylation changes in both young and old mice. We used genetically engineered C57Bl/6 mice transgenic for a cardiac-specific mutant of the mitochondrial polymerase-γ (termed Y955C). Y955C mice undergo left ventricular hypertrophy (LVH) at a young age (⼠94 days old), and LVH decompensated to CHF at old age (⼠255 days old). Results found 95 genes differentially expressed as a result of Y955C expression, while 4,452 genes were differentially expressed as a result of aging hearts. Moreover, cardiac DNA methylation patterns differed between Y955C (4,506 peaks with 68.5% hypomethylation) and aged hearts (73,286 peaks with 80.2% hypomethylated). Correlatively, of the 95 Y955C-dependent differentially expressed genes, 30 genes (31.6%) also displayed differential DNA methylation; in the 4,452 age-dependent differentially expressed genes, 342 genes (7.7%) displayed associated DNA methylation changes. Both Y955C and aging demonstrated significant enrichment of CACGTG-associated E-box motifs in differentially methylated regions. Cardiac mitochondrial polymerase dysfunction alters nuclear DNA methylation. Furthermore, aging causes a robust change in cardiac DNA methylation that is partially associated with mitochondrial polymerase dysfunction.
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Envelhecimento/genética , Metilação de DNA , DNA Polimerase Dirigida por DNA/metabolismo , Coração/fisiopatologia , Animais , DNA Polimerase gama , DNA Mitocondrial , DNA Polimerase Dirigida por DNA/genética , Eletrocardiografia , Feminino , Perfilação da Expressão Gênica , Insuficiência Cardíaca/genética , Hipertrofia Ventricular Esquerda/genética , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias Cardíacas/genética , Mitocôndrias Cardíacas/fisiologiaRESUMO
Mitochondrial dysfunction causes oxidative stress and cardiomyopathy. Oxidative stress also is a side effect of dideoxynucleoside antiretrovirals (NRTI) and is observed in NRTI-induced cardiomyopathy. We show here that treatment with the NRTI AZT {1-[(2R,4S,5S)-4-azido-5-(hydroxymethyl)oxolan-2-yl]-5-methylpyrimidine-2,4-dione} modulates cardiac gene expression epigenetically through production of mitochondrially derived reactive oxygen species. Transgenic mice with ubiquitous expression of mitochondrially targeted catalase (MCAT) and C57Bl/6 wild-type mice littermates (WT) were administered AZT (0.22 mg/day po, 35 days), and cardiac DNA and mRNA were isolated. In AZT-treated WT, 95 cardiac genes were differentially expressed compared with vehicle-treated WTs. When MCAT mice were treated with AZT, each of those 95 genes reverted toward the expression of vehicle-treated WTs. In AZT-treated WT hearts, Mthfr [5,10-methylenetetrahydrofolate reductase; a critical enzyme in synthesis of methionine cycle intermediates including S-adenosylmethionine (SAM)], was overexpressed. Steady-state abundance of SAM in cardiac extracts from AZT-treated MCAT mice increased 60% above that of vehicle-treated MCAT. No such change occurred in WT. AZT caused hypermethylation (47%) and hypomethylation (53%) of differentially methylated DNA regions in WT cardiac DNA. AZT-treated MCAT heart DNA exhibited greater hypermethylation (91%) and less hypomethylation (9%) compared with vehicle-treated MCAT controls. The gene encoding protein kinase C-α displayed multifocal epigenetic regulation caused by oxidative stress. Results show that mitochondrially derived oxidative stress in the heart hinders cardiac DNA methylation, alters steady-state abundance of SAM, alters cardiac gene expression, and promotes characteristic pathophysiological changes of cardiomyopathy. This mechanism for NRTI toxicity offers insight into long-term side effects from these commonly used antiviral agents.
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Epigênese Genética/efeitos dos fármacos , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Zidovudina/farmacologia , Animais , Catalase/metabolismo , Análise por Conglomerados , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Perfilação da Expressão Gênica , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Camundongos Endogâmicos C57BL , Mitocôndrias/efeitos dos fármacos , Análise de Sequência com Séries de Oligonucleotídeos , Estresse Oxidativo/genética , S-Adenosilmetionina/farmacologiaRESUMO
This study addresses the individual and combined effects of HIV-1 and methamphetamine (N-methyl-1-phenylpropan-2-amine, METH) on cardiac dysfunction in a transgenic mouse model of HIV/AIDS. METH is abused epidemically and is frequently associated with acquisition of HIV-1 infection or AIDS. We employed microarrays to identify mRNA differences in cardiac left ventricle (LV) gene expression following METH administration (10d, 3mg/kg/d, subcutaneously) in C57Bl/6 wild-type littermates (WT) and Tat-expressing transgenic (TG) mice. Arrays identified 880 differentially expressed genes (expression fold change>1.5, p<0.05) following METH exposure, Tat expression, or both. Using pathway enrichment analysis, mRNAs encoding polypeptides for calcium signaling and contractility were altered in the LV samples. Correlative DNA methylation analysis revealed significant LV DNA methylation changes following METH exposure and Tat expression. By combining these data sets, 38 gene promoters (27 related to METH, 11 related to Tat) exhibited differences by both methods of analysis. Among those, only the promoter for CACNA1C that encodes L-type calcium channel Cav1.2 displayed DNA methylation changes concordant with its gene expression change. Quantitative PCR verified that Cav1.2 LV mRNA abundance doubled following METH. Correlative immunoblots specific for Cav1.2 revealed a 3.5-fold increase in protein abundance in METH LVs. Data implicate Cav1.2 in calcium dysregulation and hypercontractility in the murine LV exposed to METH. They suggest a pathogenetic role for METH exposure to promote LV dysfunction that outweighs Tat-induced effects.
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Metilação de DNA/efeitos dos fármacos , Infecções por HIV/fisiopatologia , Coração/efeitos dos fármacos , Metanfetamina/farmacologia , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Animais , Canais de Cálcio Tipo L/genética , Canais de Cálcio Tipo L/metabolismo , Relação Dose-Resposta a Droga , Eletrocardiografia , Epigênese Genética , Expressão Gênica/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/efeitos dos fármacos , Regiões Promotoras Genéticas , Regulação para Cima , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismoRESUMO
For the determination of trace residues of tetracycline antibiotics in fatty food samples, selective pressurized liquid extraction coupled with high-performance liquid chromatography and tandem mass spectrometry was applied in this study. Copper(II) isonicotinate was first used as online cleanup adsorbent in the selective pressurized liquid extraction process. The adsorbent to sample ratio, extraction temperature, extraction time, and recycle times, etc. were optimized. The tetracyclines in food samples of pork, chicken meat, and clam meat were detected by liquid chromatography with tandem mass spectrometry. Tetracycline was found at levels of 0.32 and 0.53 µg/g and oxytetracycline was found at 0.14 and 0.21 µg/g in chicken meat and clam meat, respectively, while chlorotetracycline and deoxytetracycline were below the detection limit. The detection limit (S/N = 3) for these four tetracyclines were from 0.2 to 3.3 ng/g, the recoveries were from 75.8 to 110.5%, and relative standard deviations were from 5.5 to 13.6%. Copper(II) isonicotinate showed a higher purification capacity than other cleanup adsorbents for extraction of antibiotics in fatty food and the recovery showed predominance compared with a pressurized liquid extraction method without adsorbent. The study demonstrated that copper(II) isonicotinate would be a promising cleanup adsorbent in pressurized liquid extraction for the analysis of trace organic pollutants in complicated samples.
Assuntos
Antibacterianos/análise , Fracionamento Químico/métodos , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Carne/análise , Espectrometria de Massas em Tandem/métodos , Tetraciclina/análise , Animais , Galinhas , Resíduos de Drogas/isolamento & purificação , Contaminação de Alimentos/análise , SuínosRESUMO
Label-free nucleic acid fluorescent probes are gaining popularity due to their low cost and ease of application. However, the primary challenges associated with label-free fluorescent probes stem from their tendency to interact with other biomolecules, such as RNA, proteins, and enzymes, which results in low specificity. In this work, we have developed a simple detection platform that utilizes Fe3O4@PPy in combination with a label-free nucleic acid probe, 1,1,2,2-tetrakis[4-(2-bromo-ethoxy)phenyl]ethene (TTAPE) or Malachite Green (MG), for highly selective detection of metal ions, acetamiprid, and thrombin. Fe3O4@PPy not only adsorbs aptamers through electrostatic interactions, π-π bonding, and hydrogen bonding, but also quenches the fluorescence of the TTAPE/MG. Upon the addition of target compounds, the aptasensor separates from Fe3O4@PPy through magnetic separation. Moreover, by changing different aptamers, the aptasensor was applied to detect metal ions, acetamiprid, and thrombin, with the turned-on photoluminescence (PL) emission intensity recorded and showing linearity to the concentrations of targets. The robustness of method was demonstrated by applying it to real samples, which included vegetables (for detecting acetamiprid with LODs of 0.02 and 0.04 ng/L), serum samples (for detecting thrombin with LODs of 5.5 and 4.3 nM), and water samples (for detecting Pb2+ with an LOD of 0.17 nM). Therefore, due to its impressive selectivity and sensitivity, the Fe3O4@PPy aptasensor could be utilized as a universal detection platform for various clinical and environmental applications.
Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Corantes Fluorescentes , Neonicotinoides , Espectrometria de Fluorescência , Trombina , Aptâmeros de Nucleotídeos/química , Trombina/análise , Corantes Fluorescentes/química , Técnicas Biossensoriais/métodos , Neonicotinoides/análise , Espectrometria de Fluorescência/métodos , Limite de Detecção , Corantes de Rosanilina/análise , Corantes de Rosanilina/química , Humanos , Polímeros/químicaRESUMO
Electricity generation by natural water evaporation generators (NWEGs) using porous materials shows great potential for energy harvesting, but mechanistic investigations of NWEGs have mostly been limited to streaming potential studies. In this study, we propose the coexistence of an evaporation potential and streaming potential in a NWEG using ZSM-5 as the generation material. The iron probe method, salt concentration regulation, solution regulation, and side evaporation area regulation were used to analyze the NWEG mechanism. Our findings revealed that a streaming potential formed as water flowed inside the ZSM-5 nanochannels, driven by electrodynamic effects that increased from the bottom to the top of the generator. In addition, an evaporation potential existed at the surface interface between ZSM-5 and water, which decreased from the bottom to the top as the evaporation height of the generator increased. The resulting open-circuit voltage (Voc) depended on the balance between the evaporation and streaming potentials, both of which were influenced by the evaporation enthalpy (Ee) or vapor pressure. Generally, a higher Ee or lower vapor pressure led to a lower evaporation potential and subsequently a lower Voc. A dual mechanism involving synergistic evaporation potential and streaming potential is proposed to explain the mechanism of NWEGs.
RESUMO
A hyperinflammatory response is a prominent feature of feline infectious peritonitis (FIP), but the mechanisms behind the feline infectious peritonitis virus (FIPV)-induced cytokine storm in the host have not been clarified. Studies have shown that coronaviruses encode accessory proteins that are involved in viral replication and associated with viral virulence, the inflammatory response and immune regulation. Here, we found that FIPV ORF7a gene plays a key role in viral infection and host proinflammatory responses. The recombinant FIPV strains lacking ORF7a (rQS-79Δ7a) exhibit low replication rates in macrophages and do not induce dramatic upregulation of inflammatory factors. Furthermore, through animal experiments, we found that the rQS-79Δ7a strain is nonpathogenic and do not cause symptoms of FIP in cats. Unexpectedly, after three vaccinations with rQS-79Δ7a strain, humoral and cellular immunity was increased and provided protection against virulent strains in cats, and the protection rate reaches 40%. Importantly, our results demonstrated that ORF7a is a key virulence factor that exacerbates FIPV infection and inflammatory responses. Besides, our findings will provide novel implications for future development of live attenuated FIPV vaccines.
Assuntos
Infecções por Coronavirus , Coronavirus Felino , Peritonite Infecciosa Felina , Gatos , Animais , Coronavirus Felino/genética , Fatores de Virulência/genética , VirulênciaRESUMO
What is already known about this topic?: Kashin-Beck disease (KBD) is a chronic and degenerative osteoarthropathy characterized by cartilage degeneration. It is an endemic disease that is highly prevalent among the Chinese population and poses a significant health risk. What is added by this report?: This is the first national report on the economic burden of KBD in China. According to the data from 2021, KBD has caused significant disease and economic burdens. The most substantial reduction in healthy life expectancy was observed among patients with degree II severity and those aged 60 years and older, resulting in a total indirect economic burden of 112.74 million Chinese Yuan (CNY). What are the implications for public health practice?: The results of this study will contribute to informing the development of tailored prevention and control strategies by the government. These strategies will include targeted policies and recommendations for appropriate healthcare and financial subsidies, which will be based on the demographic characteristics of the endemic areas.