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1.
Viruses ; 16(4)2024 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-38675848

RESUMO

Rapid and early detection of infectious diseases in pigs is important, especially for the implementation of control measures in suspected cases of African swine fever (ASF), as an effective and safe vaccine is not yet available in most of the affected countries. Additionally, analysis for swine influenza is of significance due to its high morbidity rate (up to 100%) despite a lower mortality rate compared to ASF. The wide distribution of swine influenza A virus (SwIAV) across various countries, the emergence of constantly new recombinant strains, and the danger of human infection underscore the need for rapid and accurate diagnosis. Several diagnostic approaches and commercial methods should be applied depending on the scenario, type of sample and the objective of the studies being implemented. At the early diagnosis of an outbreak, virus genome detection using a variety of PCR assays proves to be the most sensitive and specific technique. As the disease evolves, serology gains diagnostic value, as specific antibodies appear later in the course of the disease (after 7-10 days post-infection (DPI) for ASF and between 10-21 DPI for SwIAV). The ongoing development of commercial kits with enhanced sensitivity and specificity is evident. This review aims to analyse recent advances and current commercial kits utilised for the diagnosis of ASF and SwIAV.


Assuntos
Febre Suína Africana , Vírus da Influenza A , Infecções por Orthomyxoviridae , Kit de Reagentes para Diagnóstico , Sensibilidade e Especificidade , Animais , Febre Suína Africana/diagnóstico , Febre Suína Africana/virologia , Febre Suína Africana/epidemiologia , Suínos , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/veterinária , Infecções por Orthomyxoviridae/virologia , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Vírus da Febre Suína Africana/genética , Vírus da Febre Suína Africana/isolamento & purificação , Técnicas de Laboratório Clínico/métodos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/virologia , Técnicas de Diagnóstico Molecular/métodos
2.
Front Cell Infect Microbiol ; 13: 1163569, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38125905

RESUMO

The African swine fever virus (ASFV) is strongly dependent on an intact endocytic pathway and a certain cellular membrane remodeling for infection, possibly regulated by the endosomal sorting complexes required for transport (ESCRT). The ESCRT machinery is mainly involved in the coordination of membrane dynamics; hence, several viruses exploit this complex and its accessory proteins VPS4 and ALIX for their own benefit. In this work, we found that shRNA-mediated knockdown of VPS4A decreased ASFV replication and viral titers, and this silencing resulted in an enhanced expression of ESCRT-0 component HRS. ASFV infection slightly increased HRS expression but not under VPS4A depletion conditions. Interestingly, VPS4A silencing did not have an impact on ALIX expression, which was significantly overexpressed upon ASFV infection. Further analysis revealed that ALIX silencing impaired ASFV infection at late stages of the viral cycle, including replication and viral production. In addition to ESCRT, the accessory protein ALIX is involved in endosomal membrane dynamics in a lysobisphosphatydic acid (LBPA) and Ca2+-dependent manner, which is relevant for intraluminal vesicle (ILV) biogenesis and endosomal homeostasis. Moreover, LBPA interacts with NPC2 and/or ALIX to regulate cellular cholesterol traffic, and would affect ASFV infection. Thus, we show that LBPA blocking impacted ASFV infection at both early and late infection, suggesting a function for this unconventional phospholipid in the ASFV viral cycle. Here, we found for the first time that silencing of VPS4A and ALIX affects the infection later on, and blocking LBPA function reduces ASFV infectivity at early and later stages of the viral cycle, while ALIX was overexpressed upon infection. These data suggested the relevance of ESCRT-related proteins in ASFV infection.


Assuntos
Vírus da Febre Suína Africana , Complexos Endossomais de Distribuição Requeridos para Transporte , Suínos , Animais , Complexos Endossomais de Distribuição Requeridos para Transporte/genética , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Vírus da Febre Suína Africana/genética , Proteínas de Ligação ao Cálcio/metabolismo , Endossomos/metabolismo , Endocitose
3.
Int J Mol Sci ; 24(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37762580

RESUMO

Aging is considered the deterioration of physiological functions along with an increased mortality rate. This scientific review focuses on the central importance of genomic instability during the aging process, encompassing a range of cellular and molecular changes that occur with advancing age. In particular, this revision addresses the genetic and epigenetic alterations that contribute to genomic instability, such as telomere shortening, DNA damage accumulation, and decreased DNA repair capacity. Furthermore, the review explores the epigenetic changes that occur with aging, including modifications to histones, DNA methylation patterns, and the role of non-coding RNAs. Finally, the review discusses the organization of chromatin and its contribution to genomic instability, including heterochromatin loss, chromatin remodeling, and changes in nucleosome and histone abundance. In conclusion, this review highlights the fundamental role that genomic instability plays in the aging process and underscores the need for continued research into these complex biological mechanisms.


Assuntos
Cromatina , Instabilidade Genômica , Humanos , Nucleossomos , Epigênese Genética , Histonas/genética
4.
Viruses ; 15(5)2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37243184

RESUMO

African swine fever virus (ASFV) encodes more than 150 proteins, most of them of unknown function. We used a high-throughput proteomic analysis to elucidate the interactome of four ASFV proteins, which potentially mediate a critical step of the infection cycle, the fusion and endosomal exit of the virions. Using affinity purification and mass spectrometry, we were able to identify potential interacting partners for those ASFV proteins P34, E199L, MGF360-15R and E248R. Representative molecular pathways for these proteins were intracellular and Golgi vesicle transport, endoplasmic reticulum organization, lipid biosynthesis, and cholesterol metabolism. Rab geranyl geranylation emerged as a significant hit, and also Rab proteins, which are crucial regulators of the endocytic pathway and interactors of both p34 and E199L. Rab proteins co-ordinate a tight regulation of the endocytic pathway that is necessary for ASFV infection. Moreover, several interactors were proteins involved in the molecular exchange at ER membrane contacts. These ASFV fusion proteins shared interacting partners, suggesting potential common functions. Membrane trafficking and lipid metabolism were important categories, as we found significant interactions with several enzymes of the lipid metabolism. These targets were confirmed using specific inhibitors with antiviral effect in cell lines and macrophages.


Assuntos
Vírus da Febre Suína Africana , Febre Suína Africana , Suínos , Animais , Vírus da Febre Suína Africana/fisiologia , Proteínas Virais de Fusão/metabolismo , Proteômica , Linhagem Celular
5.
Mikrochim Acta ; 190(4): 115, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36877248

RESUMO

An electrochemical sensor has been developed, by modifying screen-printed carbon devices (SPCE) with photochemically synthesized gold nanoparticles (AuNP), to determine benzyl alcohol, a preservative widely used in the cosmetic industry. To obtain the AuNP with the best properties for electrochemical sensing applications, the photochemical synthesis was optimized using chemometric tools. A response surface methodology based on central composite design was used to optimize the synthesis conditions, as irradiation time, and the concentrations of metal precursor and the capping/reducing agent (poly(diallyldimethylammonium) chloride, PDDA). The anodic current of benzyl alcohol on SPCE modified with the AuNP was used as response of the system. The best electrochemical responses were obtained using the AuNP generated by irradiating for 18 min a 7.20 [Formula: see text] 10-4 mol L-1 AuCl4--1.7% PDDA solution. The AuNP were characterized by transmission electron microscopy, cyclic voltammetry and dynamic light scattering. The nanocomposite-based sensor formed by the optimal AuNP (AuNP@PDDA/SPCE) was used to determine benzyl alcohol by linear sweep voltammetry in 0.10 mol L-1 KOH. The anodic current at + 0.017 ± 0.003 V (vs. AgCl) was used as analytical signal. Detection limit obtained under these conditions was 2.8 µg mL-1. The AuNP@PDDA/SPCE was applied to determine benzyl alcohol  in cosmetic samples.

6.
J Immunol ; 210(6): 709-720, 2023 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-36881903

RESUMO

Multistep mast cell desensitization blocks the release of mediators following IgE crosslinking with increasing doses of Ag. Although its in vivo application has led to the safe reintroduction of drugs and foods in IgE-sensitized patients at risk for anaphylaxis, the mechanisms of the inhibitory process have remained elusive. We sought to investigate the kinetics, membrane, and cytoskeletal changes and to identify molecular targets. IgE-sensitized wild-type murine (WT) and FcεRIα humanized (h) bone marrow mast cells were activated and desensitized with DNP, nitrophenyl, dust mites, and peanut Ags. The movements of membrane receptors, FcεRI/IgE/Ag, actin, and tubulin and the phosphorylation of Syk, Lyn, P38-MAPK, and SHIP-1 were assessed. Silencing SHIP-1 protein was used to dissect the SHIP-1 role. Multistep IgE desensitization of WT and transgenic human bone marrow mast cells blocked the release of ß-hexosaminidase in an Ag-specific fashion and prevented actin and tubulin movements. Desensitization was regulated by the initial Ag dose, number of doses, and time between doses. FcεRI, IgE, Ags, and surface receptors were not internalized during desensitization. Phosphorylation of Syk, Lyn, p38 MAPK, and SHIP-1 increased in a dose-response manner during activation; in contrast, only SHIP-1 phosphorylation increased in early desensitization. SHIP-1 phosphatase function had no impact on desensitization, but silencing SHIP-1 increased ß-hexoxaminidase release, preventing desensitization. Multistep IgE mast cell desensitization is a dose- and time-regulated process that blocks ß-hexosaminidase, impacting membrane and cytoskeletal movements. Signal transduction is uncoupled, favoring early phosphorylation of SHIP-1. Silencing SHIP-1 impairs desensitization without implicating its phosphatase function.


Assuntos
Actinas , Mastócitos , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases , Animais , Humanos , Camundongos , Imunoglobulina E , Fosfatidilinositol-3,4,5-Trifosfato 5-Fosfatases/genética , Monoéster Fosfórico Hidrolases , Receptores de IgE , Tubulina (Proteína)
7.
Mikrochim Acta ; 189(12): 469, 2022 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-36422711

RESUMO

New sensing platforms based on screen-printed carbon electrodes modified with composites based on polystyrene sulfonate and oxidized multi-walled carbon nanotubes (PSS/MWCNTs-COOH/SPCE) have been used to develop a novel HPLC method with electrochemical detection (ECD) for the determination of the most used synthetic phenolic antioxidants in cosmetics: butylhydroxytoluene (BHT), butylhydroxyanisole (BHA), tert-butylhydroquinone (TBHQ) and propyl gallate (PG). Optimal separation conditions were achieved using methanol: 0.10 mol L-1 acetate solution at pH 6 as mobile phase with a gradient elution program from 60 to 90% of methanol percentage in 15 min. The electrochemical detection was carried out in amperometric mode using the PSS/MWCNTs-COOH/SPCE at + 0.80 V vs. Ag. Under these optimal separation and detection conditions, the limits of detection (LOD) were between 0.11 and 0.25 mg L-1. These LOD values were better, especially for BHT, than those previously published in other HPLC methods. Linear ranges from 0.37 mg L-1, 0.83 mg L-1, 0.69 mg L-1 and 0.56 mg L-1 to 10 mg L-1 were obtained for PG, TBHQ, BHA and BHT, respectively. RSD values equal or lower than 5% and 8% were achieved for repeatability and reproducibility, respectively. The HPLC-ECD method was successfully applied to analyze different cosmetic samples. Recovery values within 83-109% were obtained in the validation studies.


Assuntos
Cosméticos , Nanocompostos , Nanotubos de Carbono , Hidroxianisol Butilado/análise , Antioxidantes , Hidroxitolueno Butilado/análise , Cromatografia Líquida de Alta Pressão/métodos , Metanol , Reprodutibilidade dos Testes , Fenóis , Eletrodos , Galato de Propila/análise
8.
Cureus ; 14(2): e22330, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35371692

RESUMO

Introduction In clinical practice, there is a binary distinction between human epidermal growth factor receptor 2 (HER2)-positive and HER2-negative (HER2-) breast cancer (BC). However, within HER2- disease, there is significant heterogeneity. Particularly, HER2- tumors that express some level of HER2 by immunohistochemistry (IHC) score 1+ or 2+/in situ hybridization (ISH) non-amplified are currently defined as HER2-low. This subgroup has shown distinct biological features compared to HER2-zero (HER2-0) BC and additionally novel antibody-drug conjugate therapies have demonstrated a potential and promising activity in HER2-low BC population. This study aims to evaluate the impact of HER2-low status in response to neoadjuvant chemotherapy (NACT) in HER2- BC being HER2-low and HER2-0 status. Materials and methods In a single institution, we retrospectively reviewed clinical and pathological data of HER2 early-stage BC patients treated with NACT following definitive surgery from January 2015 to December 2020. Tumors with HER2 IHC 0 were classified as HER2-0 and IHC score 1+ and 2+/ISH non-amplified as HER2-low. The primary objective was to evaluate the rate of pathological complete response (pCR) using the definition of ypT0/Tis ypN0 according to HER2-low and HER2-0 subgroups. Secondary objectives were to evaluate biological features between the two subgroups, disease-free survival (DFS), and overall survival (OS). Pearson chi-square, Fisher's exact, and Mann-Whitney tests were performed. The Kaplan-Meier method was used to plot DFS and OS curves. A p-value of <0.05 was considered statistically significant. Results A total of 72 patients with HER2 BC were included with a median age at diagnosis of 52.5 years and a median follow-up time of 35.5 months. Of patients, 56.9% had HER2-low disease and 43.1% had HER2-0 disease. Significant differences between the two subgroups were detected regarding hormonal receptor status and proliferation grade (Ki67). In the HER2-low subgroup, 70% of tumors were luminal-like and 64.5% of HER2-0 patients had triple-negative BC (p = 0.03). There were statistically significant differences regarding estrogen (p = 0.00) and progesterone (p = 0.02) receptors. The median Ki67 rate was higher in the HER2-0 subset (mean rank = 43.9) compared to HER2-low (mean rank = 30.9) and this difference was statistically significant (p = 0.00). HER2-low patients presented more stage III tumors (65.9%) and HER2-0 patients were mainly stage II (61.3%), and this was statistically relevant (p = 0.03). The prevalence of other clinical and pathological features was comparable between both groups. HER2-low subgroup achieved lower pCR rates (14.6% vs. 29.0%) but this difference was not statistically significant (p = 0.15). Similarly, there was no difference between the two subgroups regarding DFS (p = 0.97) and OS (p = 0.35), although the data were immature. Conclusion As in prior studies, this study did not support a significant impact of HER2-low status on response to NACT in HER2- patients with early-stage BC. HER2-low patients had a lower pCR, which may suggest a worse response to classic chemotherapy regimen and may have clinical implications that should be further exploited. The prevalence of hormonal receptors in HER2-low tumors was consistent with previous data in the literature. Although retrospective, the data suggest that HER2-low tumors should be regarded as a distinct biological subtype and more research is warranted.

9.
Talanta ; 245: 123459, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35405448

RESUMO

Parabens are chemicals widely used as preservatives in different types of industrial products. In recent years, the concern about the safety of these compounds has increased due to their endocrine disrupting activity. For this reason, their use is highly regulated and even some of them have already been banned. Thus, methods for the sensitive and selective detection of these compounds are required to control their presence in food, cosmetic, and pharmaceutical products. This paper presents an HPLC method with electrochemical detection using disposable screen-printed electrodes (SPE) for simultaneous determination of 6 different parabens in personal care products. Electrochemical behaviour of parabens was studied on SPE with different carbon-based materials as working electrode: carbon, ordered mesoporous carbon and graphene. From these studies, pH, detection potential, and the most adequate SPE were chosen. Due to the wide range of textures and viscosities (e.g., liquid, solid, and semi-solid) of personal care products, adequate sample pretreatments are required before chromatographic measurement. Here, a fast ultrasound-assisted extraction method was applied to simultaneously extract 6 parabens (methyl-, ethyl-, isopropyl-, propyl-, butyl-and benzyl-paraben) from different complex-matrix cosmetic products. Instrumental limits of detection between 20 and 115 µg L-1 were obtained applying +1.0 V (vs. Ag) as detection potential on carbon-based SPE. The total analysis time, including sample extraction and HPLC run, was shorter than 35 min. The proposed method is more versatile and faster than the current available methods and has been successfully applied to determine parabens in commercial samples such as shampoos, body creams, facial tonics, and toothpastes.


Assuntos
Cosméticos , Parabenos , Carbono , Cromatografia Líquida de Alta Pressão/métodos , Cosméticos/química , Eletrodos , Parabenos/análise
10.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408808

RESUMO

Microtubule targeting agents (MTAs) have been exploited mainly as anti-cancer drugs because of their impact on cellular division and angiogenesis. Additionally, microtubules (MTs) are key structures for intracellular transport, which is frequently hijacked during viral infection. We have analyzed the antiviral activity of clinically used MTAs in the infection of DNA and RNA viruses, including SARS-CoV-2, to find that MT destabilizer agents show a higher impact than stabilizers in the viral infections tested, and FDA-approved anti-helminthic benzimidazoles were among the most active compounds. In order to understand the reasons for the observed antiviral activity, we studied the impact of these compounds in motor proteins-mediated intracellular transport. To do so, we used labeled peptide tools, finding that clinically available MTAs impaired the movement linked to MT motors in living cells. However, their effect on viral infection lacked a clear correlation to their effect in motor-mediated transport, denoting the complex use of the cytoskeleton by viruses. Finally, we further delved into the molecular mechanism of action of Mebendazole by combining biochemical and structural studies to obtain crystallographic high-resolution information of the Mebendazole-tubulin complex, which provided insights into the mechanisms of differential toxicity between helminths and mammalians.


Assuntos
Tratamento Farmacológico da COVID-19 , Mebendazol , Animais , Antivirais/farmacologia , Mamíferos , Mebendazol/farmacologia , Microtúbulos , SARS-CoV-2 , Tubulina (Proteína)
11.
Acta Med Port ; 35(9): 672-674, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35263560

RESUMO

Hyperpigmentation of the tongue has been associated with chemotherapy, specifically cytotoxic drugs, but the exact pathophysiological mechanism is still not well understood. We describe a 37-year-old black woman that presented with tongue hyperpigmentation one week after the initiation of chemotherapy with temozolomide as a single agent. No cases of tongue hyperpigmentation associated with temozolomide as a single agent have been reported before. The diagnosis of drug associated pigmentary changes is based on the confirmation the onset of the clinical observations shortly after the initiation of the chemotherapy agent. The tongue hyperpigmentation is usually self-limited. This case constitutes a challenge for healthcare professionals and patients and emphasizes the importance of documenting these cases in order to guide healthcare professionals in managing the expectations of the patients and the potential adverse effects associated with certain drugs.


A hiperpigmentação da língua tem sido associada a quimioterapia, especificamente a fármacos citotóxicos, mas o mecanismo fisiopatológico exato não é conhecido. Apresentamos o caso clínico de uma mulher de raça negra, de 37 anos que apresentou hiperpigmentação da língua uma semana após o início da quimioterapia com temozolomida em monoterapia. Nenhum caso de hiperpigmentação da língua associada à temozolomida em monoterapia foi antes relatado. O diagnóstico de alterações pigmentares associadas ao medicamento é baseado na correlação temporal do início dos achados clínicos com o início do agente quimioterápico. A hiperpigmentação da língua geralmente é autolimitada. Este caso constitui um desafio para os profissionais de saúde e para os doentes e enfatiza a importância de documentar estes casos, a fim de orientar os profissionais de saúde na gestão das expectativas dos doentes e dos potenciais efeitos adversos associados a determinados fármacos.


Assuntos
Antineoplásicos , Hiperpigmentação , Doenças da Língua , Feminino , Humanos , Adulto , Temozolomida/efeitos adversos , Hiperpigmentação/induzido quimicamente , Língua
12.
Cureus ; 14(2): e22224, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35340486

RESUMO

Background Inflammation is a crucial component in carcinogenesis. The neutrophil-to-eosinophil ratio (NER) has been studied as a biomarker of prognosis and predictive of response in metastatic renal cell carcinoma (mRCC). In the present study, we evaluated the relevance of baseline NER on the progression-free survival (PFS) and overall survival (OS) outcomes in real-world patients with mRCC treated with nivolumab in second or subsequent lines. We also assessed the association of baseline NER with objective response, as well as with toxicity and histology. Methods In this multicenter retrospective analysis of patients with mRCC treated with nivolumab, the last systemic absolute neutrophil and eosinophil count before treatment with nivolumab was used to calculate the NER. An additive Cox proportional hazards model was used to identify the cut-off point for NER considering PFS and the patients were allocated into low and high NER groups. Median OS and median PFS were estimated using the Kaplan-Meier estimator, and survival curves of groups were compared using the log-rank test. Univariable and multivariable Cox regression models were used to study OS and PFS and Fisher's exact test was performed to evaluate the association of NER with the response, toxicity, and histology. Results The 49 analyzed patients had a median follow-up of nine months. The NER cut-off was established at 48, locating 29 patients in the low NER group (NER < 48) and 20 in the high NER group (NER ≥ 48). Median PFS and median OS were significantly shorter in patients with high NER versus low NER (3 vs. 30 months (p < 0.001) and 6 vs. 24 months (p = 0.002), respectively). Multivariable analyses showed that NER (HR 3.92 (95% CI: 1.66-9.23), p = 0.002) was an independent factor for PFS and that NER (HR 3.85 (95% CI: 1.33-11.17), p = 0.013) and progressive disease (HR 5.62 (95% CI: 1.88-16.83), p = 0.002) were independent factors for OS. NER was significantly associated with objective response rate (ORR) (NER ≥ 48-12.5% vs. NER < 48-87.5%, p = 0.003), immune-related adverse events (irAEs) (NER ≥ 48-10.0% vs. NER < 48-42.9%, p = 0.014), and tumor's histology as patients of high NER group had more non-clear cell carcinoma than low NER group (35.0% vs. 7.4%, p = 0.017). Conclusion Our real-world data analysis of NER in patients with mRCC confirmed the prognostic value of this biomarker, supporting clinical utility in predicting survival. Results also suggested an association between lower NER and better ORR, and that irAEs occur more frequently in patients with a lower NER. However, further large-scale prospective studies are needed to confirm these findings and to validate this biomarker.

13.
J Dev Orig Health Dis ; 13(5): 593-605, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-34986913

RESUMO

The addition of reproductive fluids (RF) to the culture media has shown benefits in different embryonic traits but its long-term effects on the offspring phenotype are still unknown. We aimed to describe such effects in pigs. Blood samples and growth parameters were collected from piglets derived from in vitro-produced embryos (IVP) with or without RF added in the culture media versus those artificially inseminated (AI), from day 0 to month 6 of life. An oral glucose tolerance test was performed on day 45 of life. We show here the first comparative data of the growth of animals produced through different assisted reproductive techniques, demonstrating differences between groups. Overall, there was a tendency to have a larger size at birth and faster growth in animals derived from in vitro fertilization and embryo culture versus AI, although this trend was diminished by the addition of RFs to the culture media. Similarly, small differences in hematological indices and glucose tolerance between animals derived from AI and those derived from IVP, with a sex-dependent effect, tended to fade in the presence of RF. The addition of RF to the culture media could contribute to minimizing the phenotypical differences between the in vitro-derived and AI offspring, particularly in males.


Assuntos
Fertilização in vitro , Inseminação Artificial , Animais , Meios de Cultura , Teste de Tolerância a Glucose , Masculino , Suínos
14.
PLoS Pathog ; 18(1): e1009784, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35081156

RESUMO

African swine fever virus (ASFV) infectious cycle starts with the viral adsorption and entry into the host cell. Then, the virus is internalized via clathrin/dynamin mediated endocytosis and macropinocytosis. Similar to other viruses, ASF virion is then internalized and incorporated into the endocytic pathway. While the endosomal maturation entails luminal acidification, the decrease in pH acts on the multilayer structure of the virion dissolving the outer capsid. Upon decapsidation, the inner viral membrane is exposed to interact with the limiting membrane of the late endosome for fusion. Viral fusion is then necessary for the egress of incoming virions from endosomes into the cytoplasm, however this remains an intriguing and yet essential process for infection, specifically for the egress of viral nucleic acid into the cytoplasm for replication. ASFV proteins E248R and E199L, located at the exposed inner viral membrane, might be implicated in the fusion step. An interaction between these viral proteins and cellular endosomal proteins such as the Niemann-Pick C type 1 (NPC1) and lysosomal membrane proteins (Lamp-1 and -2) was shown. Furthermore, the silencing of these proteins impaired ASFV infection. It was also observed that NPC1 knock-out cells using CRISPR jeopardized ASFV infection and that the progression and endosomal exit of viral cores was arrested within endosomes at viral entry. These results suggest that the interactions of ASFV proteins with some endosomal proteins might be important for the membrane fusion step. In addition to this, reductions on ASFV infectivity and replication in NPC1 KO cells were accompanied by fewer and smaller viral factories. Our findings pave the way to understanding the role of proteins of the endosomal membrane in ASFV infection.


Assuntos
Vírus da Febre Suína Africana/patogenicidade , Febre Suína Africana/virologia , Endossomos/virologia , Interações Hospedeiro-Patógeno/fisiologia , Proteínas Virais/metabolismo , Vírus da Febre Suína Africana/metabolismo , Animais , Chlorocebus aethiops , Endossomos/metabolismo , Células HEK293 , Humanos , Suínos , Células Vero
15.
Methods Mol Biol ; 2391: 55-62, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34686976

RESUMO

The appearance of colony growth sectors on solid medium plates has been described in many fungi. Although the molecular bases of this phenomenon remain largely unknown, possible relationships with genetic or epigenetic changes have been reported. Here we present a method to quantify the frequency of colony growth sectors in Fusarium oxysporum, which can be used to compare different fungal strains and to infer their genetic instability.


Assuntos
Fusarium/genética , Meios de Cultura
16.
Antiviral Res ; 194: 105167, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34450201

RESUMO

Niemann-Pick type C1 (NPC1) receptor is an endosomal membrane protein that regulates intracellular cholesterol traffic. This protein has been shown to play an important role for several viruses. It has been reported that SARS-CoV-2 enters the cell through plasma membrane fusion and/or endosomal entry upon availability of proteases. However, the whole process is not fully understood yet and additional viral/host factors might be required for viral fusion and subsequent viral replication. Here, we report a novel interaction between the SARS-CoV-2 nucleoprotein (N) and the cholesterol transporter NPC1. Furthermore, we have found that some compounds reported to interact with NPC1, carbazole SC816 and sulfides SC198 and SC073, were able to reduce SARS-CoV-2 viral infection with a good selectivity index in human cell infection models. These findings suggest the importance of NPC1 for SARS-CoV-2 viral infection and a new possible potential therapeutic target to fight against COVID-19.


Assuntos
Transporte Biológico , Tratamento Farmacológico da COVID-19 , Endossomos/virologia , Proteína C1 de Niemann-Pick/análise , SARS-CoV-2/fisiologia , Animais , Carbazóis/farmacologia , Chlorocebus aethiops , Endossomos/química , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Fusão de Membrana , Células Vero , Replicação Viral
17.
Viruses ; 13(6)2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-34204411

RESUMO

African swine fever virus (ASFV) is an acute and persistent swine virus with a high economic burden that encodes multiple genes to evade host immune response. In this work, we have revealed that early viral protein UBCv1, the only known conjugating enzyme encoded by a virus, modulates innate immune and inflammatory signaling. Transient overexpression of UBCv1 impaired activation of NF-κB and AP-1 transcription factors induced by several agonists of these pathways. In contrast, activation of IRF3 and ISRE signaling upon stimulation with TRIFΔRIP, cGAS/STING or RIG-I-CARD remained unaltered. Experiments aimed at mapping UBCv1 inhibitory activity indicated that this viral protein acts upstream or at the level step of IKKß. In agreement with this, UBCv1 was able to block p65 nuclear translocation upon cytokine stimulation, a key event in NF-ĸB signaling. Additionally, A549 stably transduced for UBCv1 showed a significant decrease in the levels of NF-ĸB dependent genes. Interestingly, despite the well-defined capacity of UBCv1 to conjugate ubiquitin chains, a mutant disabled for ubiquitylation activity retained similar immunomodulatory activity as the wild-type enzyme, suggesting that the two functions are segregated. Altogether these data suggest that ASFV UBCv1 manipulates the innate immune response targeting the NF-κB and AP-1 pathways and opens new questions about the multifunctionality of this enzyme.


Assuntos
Vírus da Febre Suína Africana/enzimologia , Imunidade Inata , Imunomodulação , NF-kappa B/genética , Enzimas de Conjugação de Ubiquitina/genética , Enzimas de Conjugação de Ubiquitina/imunologia , Células A549 , Vírus da Febre Suína Africana/imunologia , Animais , Células HEK293 , Humanos , Interferon Tipo I/imunologia , NF-kappa B/imunologia , NF-kappa B/metabolismo , Transdução de Sinais/imunologia , Suínos , Ubiquitina/metabolismo , Enzimas de Conjugação de Ubiquitina/metabolismo
18.
CRISPR J ; 4(1): 132-146, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33616447

RESUMO

Studies of knockout (KO) mice with defects in the endolysosomal two-pore channels (TPCs) have shown TPCs to be involved in pathophysiological processes, including heart and muscle function, metabolism, immunity, cancer, and viral infection. With the objective of studying TPC2's pathophysiological roles for the first time in a large, more humanlike animal model, TPC2 KO pigs were produced using CRISPR-Cas9. A major problem using CRISPR-Cas9 to edit embryos is mosaicism; thus, we studied for the first time the effect of microinjection timing on mosaicism. Mosaicism was greatly reduced when in vitro produced embryos were microinjected before insemination, and surgical embryo transfer (ET) was performed using such embryos. All TPC2 KO fetuses and piglets born following ET (i.e., F0 generation) were nonmosaic biallelic KOs. The generation of nonmosaic animals greatly facilitates germ line transmission of the mutation, thereby aiding the rapid and efficient generation of KO animal lines for medical research and agriculture.


Assuntos
Sistemas CRISPR-Cas , Técnicas de Inativação de Genes/métodos , Inseminação , Microinjeções/métodos , Oócitos , Suínos/genética , Animais , Canais de Cálcio/genética , Transferência Embrionária , Embrião de Mamíferos , Feminino , Fertilização , Feto , Células Germinativas , Cariótipo , Masculino , Camundongos , Camundongos Knockout , Modelos Animais , Mosaicismo , Mutação , Fenótipo , RNA Guia de Cinetoplastídeos , Zigoto
19.
Front Vet Sci ; 8: 739041, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35083305

RESUMO

Assisted reproductive technologies play a major role in the cattle industry. An increase in the use of in vitro-derived embryos is currently being seen around the globe. But the efficiency and quality of the in vitro-derived embryos are substandard when compared to the in vivo production. Different protocols have been designed to overcome this issue, one of those being the use of reproductive fluids as supplementation to embryo culture media. In this study, in vitro-derived calves produced with reproductive fluids added to their embryo production protocol were followed for the first year of life pairwise with their in vivo control, produced by artificial insemination (AI), and their in vitro control, produced with standard supplementation in embryo production. The objective was to assess if any differences could be found in terms of growth and development as well as hematological and biochemical analytes between the different systems. All the analysed variables (physical, hematological, and biochemical) were within physiological range and very similar between calves throughout the entire experiment. However, differences were more evident between calves derived from standard in vitro production and AI. We concluded that the use of reproductive fluids as a supplementation to the embryo culture media results in calves with closer growth and development patterns to those born by AI than the use of bovine serum albumin as supplementation.

20.
Virulence ; 11(1): 1108-1121, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32862758

RESUMO

Cu is an essential trace element for cell growth and proliferation. However, excess of Cu accumulation leads to cellular toxicity. Thus, precise and tight regulation of Cu homeostasis processes, including transport, delivery, storage, detoxification, and efflux machineries, is required. Moreover, the maintenance of Cu homeostasis is critical for the survival and virulence of fungal pathogens. Cu homeostasis has been extensively studied in mammals, bacteria, and yeast, but it has not yet been well documented in filamentous fungi. In the present work, we investigated Cu tolerance in the filamentous fungus Fusarium oxysporum by analysing the Cu transporter coding gene crpF, previously studied in Aspergillus fumigatus. The expression studies demonstrated that crpF is upregulated in the presence of Cu and its deletion leads to severe sensitivity to low levels of CuSO4 in F. oxysporum. Targeted deletion of crpF did not significantly alter the resistance of the fungus to macrophage killing, nor its pathogenic behaviour on the tomato plants. However, the targeted deletion mutant ΔcrpF showed increased virulence in a murine model of systemic infection compared to wild-type strain (wt).


Assuntos
Proteínas de Transporte de Cobre/genética , Cobre/toxicidade , Proteínas Fúngicas/genética , Fusarium/química , Fusarium/efeitos dos fármacos , Animais , Linhagem Celular , Sulfato de Cobre/farmacologia , Proteínas de Transporte de Cobre/metabolismo , Proteínas Fúngicas/metabolismo , Fusarium/patogenicidade , Deleção de Genes , Regulação Fúngica da Expressão Gênica , Homeostase , Solanum lycopersicum/microbiologia , Macrófagos/microbiologia , Masculino , Camundongos , Doenças das Plantas/microbiologia , Virulência
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