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1.
Int J Mol Sci ; 25(15)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39125964

RESUMO

Photorespiration, caused by oxygenation of the enzyme Rubisco, is considered a wasteful process, because it reduces photosynthetic carbon gain, but it also supplies amino acids and is involved in amelioration of stress. Here, we show that a sudden increase in photorespiratory activity not only reduced carbon acquisition and production of sugars and starch, but also affected diurnal dynamics of amino acids not obviously involved in the process. Flux calculations based on diurnal metabolite profiles suggest that export of proline from leaves increases, while aspartate family members accumulate. An immense increase is observed for turnover in the cyclic reaction of glutamine synthetase/glutamine-oxoglutarate aminotransferase (GS/GOGAT), probably because of increased production of ammonium in photorespiration. The hpr1-1 mutant, defective in peroxisomal hydroxypyruvate reductase, shows substantial alterations in flux, leading to a shift from the oxoglutarate to the aspartate family of amino acids. This is coupled to a massive export of asparagine, which may serve in exchange for serine between shoot and root.


Assuntos
Aminoácidos , Arabidopsis , Nitrogênio , Fotossíntese , Aminoácidos/metabolismo , Nitrogênio/metabolismo , Arabidopsis/metabolismo , Arabidopsis/genética , Folhas de Planta/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo
2.
J Aquat Anim Health ; 35(4): 296-307, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38124493

RESUMO

OBJECTIVE: The objectives of this study were to describe spatiotemporal patterns of infectious salmon anemia virus (ISAV) detections in marine salmonid production sites in the province of Newfoundland and Labrador in Canada. METHODS: Infectious salmon anemia virus surveillance data between 2012 and 2020 from the province of Newfoundland and Labrador were used. Data comprised a total of 94 sampling events from 20 Atlantic Salmon Salmo salar production sites in which ISAV was detected. Using linear regression models, factors influencing time to detection (days from stocking to first ISAV detection) and time to depopulation (days from first detection to production site depopulation) were investigated. RESULT: Based on 28 unique cases, site-level annual incidence risk of ISAV detection ranged from 3% to 29%. The proportion of ISAV detection by PCR in fish samples ranged from 2% to 45% annually. Overall, ISAV variants from the European clade were more common than variants from the North American clade. The type of ISAV clade, detections of ISAV in nearest production sites based on seaway distances, and year of infectious salmon anemia cases were not associated with time to first ISAV detection. Time to depopulation for sites infected with the ISAV-HPRΔ variant was not associated with ISAV North American or European clades. CONCLUSION: Our results contribute to the further understanding of the changing dynamics of infectious salmon anemia detections in Newfoundland and Labrador since its first detection in 2012 and will likely assist in the design of improved disease surveillance and control programs in the province.


Assuntos
Anemia , Doenças dos Peixes , Isavirus , Infecções por Orthomyxoviridae , Salmo salar , Animais , Isavirus/genética , Terra Nova e Labrador/epidemiologia , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Anemia/veterinária , Doenças dos Peixes/epidemiologia
3.
Mol Microbiol ; 115(6): 1207-1228, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33325565

RESUMO

Catabolite control protein A (CcpA) is a master regulator of carbon source utilization and contributes to the virulence of numerous medically important Gram-positive bacteria. Most functional assessments of CcpA, including interaction with its key co-factor HPr, have been performed in nonpathogenic bacteria. In this study we aimed to identify the in vivo DNA binding profile of CcpA and assess the extent to which HPr is required for CcpA-mediated regulation and DNA binding in the major human pathogen group A Streptococcus (GAS). Using a combination RNAseq/ChIP-seq approach, we found that CcpA affects transcript levels of 514 of 1667 GAS genes (31%) whereas direct DNA binding was identified for 105 GAS genes. Three of the directly regulated genes encode the key GAS virulence factors Streptolysin S, PrtS (IL-8 degrading proteinase), and SpeB (cysteine protease). Mutating CcpA Val301 to Ala (strain 2221-CcpA-V301A) abolished interaction between CcpA and HPr and impacted the transcript levels of 205 genes (40%) in the total CcpA regulon. By ChIP-seq analysis, CcpAV301A bound to DNA from 74% of genes bound by wild-type CcpA, but generally with lower affinity. These data delineate the direct CcpA regulon and clarify the HPr-dependent and independent activities of CcpA in a key pathogenic bacterium.


Assuntos
Proteínas de Bactérias/metabolismo , DNA Bacteriano/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação Bacteriana da Expressão Gênica/genética , Streptococcus pyogenes/metabolismo , Proteínas de Bactérias/genética , Proteínas de Transporte/metabolismo , Cromatina/genética , DNA Bacteriano/genética , Proteínas de Ligação a DNA/genética , Exotoxinas/genética , Genoma Bacteriano/genética , Ligação Proteica/fisiologia , RNA-Seq , Proteínas Repressoras/metabolismo , Serina Endopeptidases/genética , Streptococcus pyogenes/genética , Streptococcus pyogenes/patogenicidade , Estreptolisinas/genética , Virulência/genética , Fatores de Virulência/genética
4.
J Comput Aided Mol Des ; 36(7): 507-520, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35809194

RESUMO

Enterococcus faecalis, a gram-positive bacterium, is among the most common nosocomial pathogens due to its limited susceptibility to antibiotics and its reservoir of the genes coding for virulence factors. Bacterial enzymes such as kinases and phosphorylases play important roles in diverse functions of a bacterial cell and, thus, are potential antibacterial drug targets. In Gram-positive bacteria, HPr Kinase/Phosphorylase (HPrK/P), a bifunctional enzyme is involved in the regulation of carbon catabolite repression by phosphorylating/dephosphorylating the histidine-containing phosphocarrier protein (HPr) at Ser46 residue. Deficiencies in HPrK/P function leads to severe defects in bacterial growth. This study aimed at identifying novel inhibitors of E. faecalis HPrK/P from a commercial compound library using structure-based virtual screening. The hit molecules were purchased and their effect on enzyme activity and growth of resistant E. faecalis was evaluated in vitro. Furthermore, docking and molecular dynamics simulations were performed to study the interactions of the hit compounds with HPrK/P. Among the identified hit molecules, two compounds inhibited the phosphorylation of HPr as well as significantly reduced the growth of resistant E. faecalis in vitro. These identified potential HPrK/P inhibitors open new research avenues towards the development of novel antimicrobials against resistant Gram-positive bacteria.


Assuntos
Anti-Infecciosos , Proteínas de Bactérias , Enterococcus faecalis , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/antagonistas & inibidores , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/enzimologia , Fosforilases/antagonistas & inibidores , Fosforilação , Proteínas Serina-Treonina Quinases/antagonistas & inibidores
5.
J Fish Dis ; 45(6): 919-930, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397120

RESUMO

An incursion of infectious salmon anaemia virus (ISAV) was detected in 2020 in southern Newfoundland, Canada. This resulted in an outbreak affecting four marine farms stocking Atlantic salmon (Salmo salar L.) vaccinated against ISAV. This study provides the first description of epidemiologic characteristics of an ISAV outbreak in 2020 and 2021, and detected ISAV variants at the population level. Fish kidneys were screened for ISAV by real-time RT-PCR and non-negative samples were submitted for genotyping and further diagnostic testing. Nine distinct ISAV variants were identified: five European and three North American (NA) HPRΔ ISAV, and one NA-HPR0 ISAV variant. A notable finding was the concurrent detection of both an HPR0 and an HPRΔ ISAV variant in one individual fish. In two farms, both European and NA variants were simultaneously detected, while in the other two farms either NA or European variants were identified, but not both together. Generally, mortality increases followed rises in ISAV prevalence and cycle threshold values on RT-PCR decreased with time. Epidemiologic descriptions of ISAV outbreaks in Atlantic Canada contributes to the understanding of local disease dynamics and identification of changes thereof. Such insights are essential for the strengthening of disease management plans.


Assuntos
Doenças dos Peixes , Isavirus , Infecções por Orthomyxoviridae , Salmo salar , Animais , Canadá , Doenças dos Peixes/epidemiologia , Isavirus/genética , Terra Nova e Labrador , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/veterinária , Filogenia
6.
J Fish Dis ; 45(3): 479-483, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34843624

RESUMO

ISAV is the causative agent of the infectious salmon anaemia (ISA), a disease listed by the OIE that has caused important economic losses to the Atlantic salmon (Salmo salar) industry. ISAV variants are identified as pathogenic or non-pathogenic based on the presence or absence of a deletion in the highly polymorphic region (HPR) of segment 6 (S6). HPRΔ variants (pathogenic) are the only forms of the virus known to grow in cell culture. This is the first report of a HPR0 variant isolated in cell culture. The isolate is, however, atypical as it shows a marker of virulent variants on another segment (S5), which has never been reported for any other HPR0 variants. The significance of this finding remains unclear until more in-depth work is carried out but does challenge current knowledge.


Assuntos
Doenças dos Peixes , Isavirus , Infecções por Orthomyxoviridae , Salmo salar , Animais , Técnicas de Cultura de Células , Isavirus/genética , Infecções por Orthomyxoviridae/veterinária , Salmão
7.
Molecules ; 27(23)2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36500687

RESUMO

Microbial Electrolysis Cells (MECs) are one of the bioreactors that have been used to produce bio-hydrogen by biological methods. The objective of this comprehensive review is to study the effects of MEC configuration (single-chamber and double-chamber), electrode materials (anode and cathode), substrates (sodium acetate, glucose, glycerol, domestic wastewater and industrial wastewater), pH, temperature, applied voltage and nanomaterials at maximum bio-hydrogen production rates (Bio-HPR). The obtained results were summarized based on the use of nanomaterials as electrodes, substrates, pH, temperature, applied voltage, Bio-HPR, columbic efficiency (CE) and cathode bio-hydrogen recovery (C Bio-HR). At the end of this review, future challenges for improving bio-hydrogen production in the MEC are also discussed.


Assuntos
Fontes de Energia Bioelétrica , Eletrólise/métodos , Eletrodos , Hidrogênio , Reatores Biológicos
8.
Neurol Sci ; 42(7): 2829-2835, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33179196

RESUMO

OBJECTIVE: Diabetes mellitus (DM) had been discovered as an independent risk factor for high on-treatment platelet reactivity (HPR) in patients with ischemic stroke. However, studies on the relationship between prediabetes and the occurrence of HPR remain scarce. This study is aimed at clarifying the association between prediabetes and HPR among patients with recent ischemic stroke or transient ischemic stroke (TIA). METHODS: Patients with ischemic stroke or TIA within 90 days after onset were recruited consecutively. All patients were divided into three groups: DM, prediabetes, and normal glucose tolerance according to fasting glucose, HbA1c, or OGTT. Three months later, all patients were performed platelet aggregation inhibition test and screened for high on-treatment platelet reactivity. The effect of prediabetes on HPR was analyzed in a multivariable logistic regression model. RESULTS: This study recruited 237 patients with ischemic stroke or TIA, including 57 cases with prediabetes, 108 with DM, and 72 with normal glucose tolerance. Aspirin and/or clopidogrel resistance was discovered in 28 cases among prediabetes group, which was significantly more frequent than normal glucose tolerance group(49.1% versus 33.3%, P = 0.046). After adjusting for confounding factors, prediabetes was found as an independent risk factor for high on-treatment platelet reactivity (HPR) among patients with recent ischemic stroke or TIA (odds ratio 2.92; 95% CI, 1.29 to 6.63, P = 0.01). CONCLUSIONS: Prediabetes was an independent risk factor for high on-treatment platelet reactivity in patients with recent ischemic cerebrovascular disease. Patients with prediabetes should be highlighted for the efficacy test of antiplatelet drugs.


Assuntos
Isquemia Encefálica , Ataque Isquêmico Transitório , AVC Isquêmico , Estado Pré-Diabético , Acidente Vascular Cerebral , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/epidemiologia , Clopidogrel/uso terapêutico , Humanos , Ataque Isquêmico Transitório/tratamento farmacológico , Ataque Isquêmico Transitório/epidemiologia , Inibidores da Agregação Plaquetária/uso terapêutico , Estado Pré-Diabético/epidemiologia , Acidente Vascular Cerebral/tratamento farmacológico , Acidente Vascular Cerebral/epidemiologia , Resultado do Tratamento
9.
Apoptosis ; 25(3-4): 217-232, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32006189

RESUMO

Glioblastoma is the most malignant and prevalent brain tumor in adults. It can grow and spread quickly causing harm to the brain health. One of the major challenges in treatment of glioblastoma is drug resistance. Use of synergistic combination of two drugs with different anti-tumor effects is nowadays highly considered in the development of effective therapeutic strategies for many malignancies. In the present study, we showed synergistic therapeutic efficacies of two chemical compounds, N-(4-hydroxyphenyl) retinamide (4HPR) and suberoylanilide hydroxamic acid (SAHA), for significant reduction in cell viability of rat C6 and human T98G glioblastoma cells. These compounds (4HPR and SAHA) were used alone or in synergistic combination for evaluating their various anti-tumor effects. The results showed that combination of 4HPR and SAHA significantly induced morphological and molecular features of astrocytic differentiation in C6 and T98G glioblastoma cells. Combination of 4HPR and SAHA proved to be an important therapeutic strategy for inhibiting cell growth and inducing differentiation in glioblastoma cells. Furthermore, combination of the two drugs showed more efficacies than either dug alone in reducing in vitro cell invasion (transwell assay), cell migration (wound healing assay), and angiogenesis (tube formation assay) due to down regulation of the molecules involved in these processes. The ultimate of goal of using this combination of drugs was induction of apoptosis. The results showed that these drugs in synergistic combination contributed highly to increases in morphological and molecular features of apoptotic death in the tumor cells. The results from molecular studies indicated that cell death occurred via activation of the extrinsic and intrinsic pathways of apoptosis in both C6 and T98G cells. The drugs in combination also contributed to dramatic inhibition of histone deacetylase 1, an important epigenetic player in promoting growth in glioblastoma cells. This novel combination of drugs should also be considered as a promising therapeutic strategy for the treatment of glioblastoma in vivo.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Fenretinida/farmacologia , Glioblastoma/patologia , Vorinostat/farmacologia , Proteínas Angiogênicas/metabolismo , Animais , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Sinergismo Farmacológico , Glioblastoma/tratamento farmacológico , Histona Desacetilase 1/antagonistas & inibidores , Humanos , Ratos
10.
New Phytol ; 228(1): 179-193, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32406528

RESUMO

C2H2-type zinc finger transcription factor sensitive to proton rhizotoxicity 1 (STOP1) plays an essential role in aluminium (Al) resistance in Arabidopsis thaliana by controlling the expression of a set of Al-resistance genes, including the malate transporter-encoding gene A. thaliana aluminium activated malate transporter 1 (AtALMT1) that is critically required for Al resistance. STOP1 is suggested to be modulated by Al at post-transcriptional and/or post-translational levels. However, the underlying molecular mechanisms remain to be demonstrated. We carried out a forward genetic screen on an ethyl methanesulphonate mutagenized population, which contains the AtALMT1 promoter-driven luciferase reporter gene (pAtALMT1:LUC), and identified hyperrecombination protein 1 (HPR1), which encodes a subunit of the THO/TREX complex. We investigate the effect of hpr1 mutations on the expression of Al-resistance genes and Al resistance, and we also examined the regulatory role of HPR1 in nuclear messenger RNA (mRNA) and protein accumulation of STOP1 gene. Mutation of HPR1 reduces the expression of STOP1-regulated genes and the associated Al resistance. The hpr1 mutations increase STOP1 mRNA retention in the nucleus and consequently decrease STOP1 protein abundance. Mutation of regulation of AtALMT1 expression 1 (RAE1) that mediates STOP1 degradation in the hpr1 mutant background can partially rescue the deficient phenotypes of hpr1 mutants. Our results demonstrate that HPR1 modulates Al resistance partly through the regulation of nucleocytoplasmic STOP1 mRNA export.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Alumínio/toxicidade , Arabidopsis/genética , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Regulação da Expressão Gênica de Plantas , Mutação/genética , Fatores de Transcrição
11.
J Appl Microbiol ; 129(1): 85-97, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31885186

RESUMO

Aquaculture has a long history in many parts of the world, but it is still young at an industrial scale. Marine fish farming in open nets of a single fish species at high densities compared to their wild compatriots opens a plethora of possible infections. Infectious salmon anaemia (ISA) is an example of disease that surfaced after large-scale farming of Atlantic salmon (Salmo salar) appeared. Here, a review of the molecular biology of the ISA virus (ISAV) with emphasis on its pathogenicity is presented. The avirulent HPR0 variant of ISAV has resisted propagation in cell cultures, which has restricted the ability to perform in vivo experiments with this variant. The transition from avirulent HPR0 to virulent HPRΔ has not been methodically studied under controlled experimental conditions, and the triggers of the transition from avirulent to virulent forms have not been mapped. Genetic segment reassortment, recombination and mutations are important mechanisms in ISAV evolution, and for the development of virulence. In the 25 years since the ISAV was identified, large amounts of sequence data have been collected for epidemiologic and transmission studies, however, the lack of good experimental models for HPR0 make the risk evaluation of the presence of this avirulent, ubiquitous variant uncertain. This review summarizes the current knowledge related to molecular biology and pathogenicity of this important aquatic orthomyxovirus.


Assuntos
Doenças dos Peixes/virologia , Isavirus/genética , Isavirus/patogenicidade , Infecções por Orthomyxoviridae/veterinária , Salmo salar/virologia , Animais , Evolução Molecular , Pesqueiros , Isavirus/crescimento & desenvolvimento , Mutação , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Proteínas Virais/genética , Virulência/genética
12.
J Biol Chem ; 293(16): 5781-5792, 2018 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-29514981

RESUMO

Utilization of energy-rich carbon sources such as glucose is fundamental to the evolutionary success of bacteria. Glucose can be catabolized via glycolysis for feeding the intermediary metabolism. The methylglyoxal synthase MgsA produces methylglyoxal from the glycolytic intermediate dihydroxyacetone phosphate. Methylglyoxal is toxic, requiring stringent regulation of MgsA activity. In the Gram-positive bacterium Bacillus subtilis, an interaction with the phosphoprotein Crh controls MgsA activity. In the absence of preferred carbon sources, Crh is present in the nonphosphorylated state and binds to and thereby inhibits MgsA. To better understand the mechanism of regulation of MgsA, here we performed biochemical and structural analyses of B. subtilis MgsA and of its interaction with Crh. Our results indicated that MgsA forms a hexamer (i.e. a trimer of dimers) in the crystal structure, whereas it seems to exist in an equilibrium between a dimer and hexamer in solution. In the hexamer, two alternative dimers could be distinguished, but only one appeared to prevail in solution. Further analysis strongly suggested that the hexamer is the biologically active form. In vitro cross-linking studies revealed that Crh interacts with the N-terminal helices of MgsA and that the Crh-MgsA binding inactivates MgsA by distorting and thereby blocking its active site. In summary, our results indicate that dimeric and hexameric MgsA species exist in an equilibrium in solution, that the hexameric species is the active form, and that binding to Crh deforms and blocks the active site in MgsA.


Assuntos
Bacillus subtilis/metabolismo , Proteínas de Bactérias/metabolismo , Carbono-Oxigênio Liases/metabolismo , Fosfoproteínas/metabolismo , Mapas de Interação de Proteínas , Bacillus subtilis/química , Proteínas de Bactérias/química , Ciclo do Carbono , Carbono-Oxigênio Liases/química , Cristalografia por Raios X , Modelos Moleculares , Fosfoproteínas/química , Conformação Proteica , Multimerização Proteica
13.
Plant J ; 93(3): 431-444, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29222952

RESUMO

Secondary metabolites are involved in the plant stress response. Among these are scopolin and its active form scopoletin, which are coumarin derivatives associated with reactive oxygen species scavenging and pathogen defence. Here we show that scopolin accumulation can be induced in the root by osmotic stress and in the leaf by low-temperature stress in Arabidopsis thaliana. A genetic screen for altered scopolin levels in A. thaliana revealed a mutant compromised in scopolin accumulation in response to stress; the lesion was present in a homologue of THO1 coding for a subunit of the THO/TREX complex. The THO/TREX complex contributes to RNA silencing, supposedly by trafficking precursors of small RNAs. Mutants defective in THO, AGO1, SDS3 and RDR6 were impaired with respect to scopolin accumulation in response to stress, suggesting a mechanism based on RNA silencing such as the trans-acting small interfering RNA pathway, which requires THO/TREX function.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Cumarínicos/metabolismo , Glucosídeos/metabolismo , Estresse Fisiológico/fisiologia , Proteínas de Arabidopsis/genética , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Cumarínicos/análise , Glucosídeos/análise , Glucosídeos/genética , Microscopia de Fluorescência , Complexos Multiproteicos/genética , Complexos Multiproteicos/metabolismo , Mutação , Pressão Osmótica , Folhas de Planta/genética , Folhas de Planta/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Interferência de RNA , Precursores de RNA/metabolismo , RNA Polimerase Dependente de RNA/genética , RNA Polimerase Dependente de RNA/metabolismo , Sacarose/metabolismo , Temperatura
14.
Platelets ; 29(3): 257-264, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29580115

RESUMO

P2Y12 receptor inhibitors are antiplatelet agents commonly prescribed in the treatment of coronary artery disease. Their efficacy can be limited by high on-treatment platelet reactivity (HPR), which can be evaluated by different biological assays. Most commonly, HPR is evaluated by flow cytometric vasodilator-stimulated phosphoprotein-phosphorylation (VASP-P) assay, which can be time consuming. To evaluate the potential interest of novel technologies, we compared four different assays. Ninety patients receiving P2Y12 inhibitors were included. Four technologies were evaluated: the current standard test measuring VASP-P by flow cytometry, the historical reference test based on light transmittance aggregation (LTA), and two relatively novel techniques: whole blood multiple electrode aggregometry (MEA) and platelet function analyzer (PFA), which are less time consuming. The three latter tests were compared with the VASP-P assay as a reference using receiver operating characteristics (ROC) analysis: LTA has an excellent comparability with the VASP test (ROC AUC > 0.9); the other two tests (multiplate and PFA) have only satisfactory comparability (ROC AUC around 0.7) and therefore may not replace the VASP "gold standard" test, if importance is attached to a quantitative assessment of the substitution parameter of VASP. Nevertheless, if a binary approach of the anti-aggregation result is sought, then one can conclude that the three tests are equivalent since Cohen's kappa coefficients are very close for the three tests (k = 0.548 for LTA; k = 0.554 for MEA; k = 0.570 for PFA/P2Y), and a similar proportion of patients are misclassified (15% for LTA, 14% for MEA, and 13.6% for PFA). Discriminant factor analysis using all the parameters provided by each test did not improve the diagnostic performance of MEA or PFA. In conclusion, only LTA shows a good comparability to the VASP assay using ROC curve analysis, probably because misclassified patients have results close to the cutoff values. All three tests have moderate agreement regarding the classification of patients as responders to P2Y12 inhibition.


Assuntos
Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Ativação Plaquetária/efeitos dos fármacos , Inibidores da Agregação Plaquetária/farmacologia , Testes de Função Plaquetária/métodos , Antagonistas do Receptor Purinérgico P2Y/farmacologia , Receptores Purinérgicos P2Y12/metabolismo , Idoso , Idoso de 80 Anos ou mais , Interações Medicamentosas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes de Função Plaquetária/normas , Curva ROC
15.
Adv Exp Med Biol ; 1062: 199-213, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29845535

RESUMO

Signal-dependent movement of proteins into and out of the nucleus through the importin superfamily of transporters is central to the replication of many viruses in infected cells, including RNA viruses such as the flavivirus Dengue virus (DENV). DENV non-structural protein 5 (NS5) traffics into and out of the host cell nucleus/nucleolus, being observed in the nucleus, although to differing extents, very early in infection in the case of all 4 DENV serotypes; with results from both reverse genetics and inhibitor studies indicating that this trafficking is critical to DENV infection. Knowledge of the transporters and targeting signals responsible for nuclear trafficking of NS5 has enabled inhibitors of DENV NS5 nuclear import to be identified using a novel screening/counterscreen approach. N-(4-hydroxyphenyl) retinamide (4-HPR) is of particular interest as a specific, non-toxic inhibitor able to protect against infection by all four serotypes of DENV, as well as the severe, antibody-enhanced form of DENV infection, in a lethal mouse model. Since 4-HPR can also inhibit DENV-related flaviviruses of medical significance such as West Nile Virus and Zika virus, it is of great interest for future commercialisation. Targeting nucleocytoplasmic trafficking of flavivirus proteins promises to be a powerful strategy to counter flaviviruses, for which the development of protective vaccines has thus far proven problematic.


Assuntos
Transporte Ativo do Núcleo Celular/efeitos dos fármacos , Antivirais/farmacologia , Vírus da Dengue/metabolismo , Dengue/virologia , Proteínas não Estruturais Virais/metabolismo , Animais , Vírus da Dengue/efeitos dos fármacos , Vírus da Dengue/genética , Humanos , Transporte Proteico/efeitos dos fármacos , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/genética
16.
J Fish Dis ; 41(3): 421-430, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28782809

RESUMO

The infectious salmon anaemia virus (ISAV) is an important viral disease of farmed Atlantic salmon that has caused considerable financial losses for salmon farmers around the world, including Atlantic Canada. It is listed as a notifiable disease by the World Organization for Animal Health, and to this day, culling of infected cages or farms remains the current practice in many countries to mitigate the spread of the virus. In Atlantic Canada, ISAV was first detected in 1996 and continues to be detected. While some outbreaks seemed to have arisen from isolated infections of unknown source, others were local clusters resulting from horizontal spread of infection. This study provides a description of the detected ISAV isolates in Atlantic Canada between 2012 and 2016, and explores the phylogenetic relatedness between these ISAV isolates. A key finding is the detection for the first time of a North American-HPR0 ISAV subtype, which was predicted to exist for many years. Through phylogenetic analysis, a scenario emerges with at least three separate incursions of ISAV in Atlantic Canada. An initial ISAV introduction follows a genotypic separation between North America and Europe which resulted in the NA and EU genotypes known today; this separation predates the salmon aquaculture industry. The second incursion of ISAV from Europe to North America led to a sublineage in Atlantic Canada consisting of EU-HPR∆ isolates detected in Nova Scotia and New Brunswick, and the predominant form of ISAV-HPR0 (EU). Finally, we observed what could be the third and most recent incursion of ISAV in Newfoundland, in the form of an isolate highly similar to ISAV EU-HPR0 isolates found in the Faroe Islands and the one isolate from Norway.


Assuntos
Doenças dos Peixes/virologia , Genótipo , Isavirus/fisiologia , Infecções por Orthomyxoviridae/veterinária , Salmão , Proteínas Virais/genética , Sequência de Aminoácidos , Animais , Canadá , Isavirus/classificação , Isavirus/genética , Infecções por Orthomyxoviridae/virologia , Filogenia , Filogeografia , Alinhamento de Sequência , Proteínas Virais/química , Proteínas Virais/metabolismo
17.
J Liposome Res ; 28(1): 5-13, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27733083

RESUMO

Keloids were characterized by excessive growth of fibrous tissues, and shared several pathological characteristics with cancer. They did put physical and emotional stress on patients in that keloids could badly change appearance of patients. N-(4-hydroxyphenyl) retinamide (4HPR) showed cytotoxic activity on a wide variety of invasive-growth cells. Our work was aim to prepare N-(4-hydroxyphenyl) retinamide-loaded lipid microbubbles (4HPR-LM) combined with ultrasound for anti-keloid therapy. 4HPR-loaded liposomes (4HPR-L) were first prepared by film evaporation method, and then 4HPR-LM were manufactured by mixing 4HPR-L and perfluoropentane (PFP) with ultrasonic cavitation method. The mean particle size and entrapment efficiency 4HPR-LM were 113 nm and 95%, respectively. The anti-keloids activity of 4HPR-LM was assessed with BALB/c nude mice bearing subcutaneous xenograft keloids model. 4HPR-LM, combined with ultrasound, could significantly induce apoptosis of keloid fibroblasts in vitro and inhibited growth of keloids in vivo. Thus, 4HPR-LM could be considered as a promising agent for anti-keloids therapy.


Assuntos
Fenretinida/farmacologia , Queloide/terapia , Lipídeos/química , Lipossomos , Nanopartículas , Ondas Ultrassônicas , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fenretinida/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Humanos , Camundongos Endogâmicos BALB C , Camundongos Nus , Tamanho da Partícula , Propriedades de Superfície
18.
Int J Cancer ; 141(2): 405-413, 2017 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-28340497

RESUMO

We previously reported that concurrent ketoconazole, an oral anti-fungal agent and P450 enzyme inhibitor, increased plasma levels of the cytotoxic retinoid, fenretinide (4-HPR) in mice. We have now determined the effects of concurrent ketoconazole on 4-HPR cytotoxic dose-response in four neuroblastoma (NB) cell lines in vitro and on 4-HPR activity against two cell line-derived, subcutaneous NB xenografts (CDX) and three patient-derived NB xenografts (PDX). Cytotoxicity in vitro was assessed by DIMSCAN assay. Xenografted animals were treated with 4-HPR/LXS (240 mg/kg/day) + ketoconazole (38 mg/kg/day) in divided oral doses in cycles of five continuous days a week. In one model, intratumoral levels of 4-HPR and metabolites were assessed by HPLC assay, and in two models intratumoral apoptosis was assessed by TUNEL assay, on Day 5 of the first cycle. Antitumor activity was assessed by Kaplan-Meier event-free survival (EFS). The in vitro cytotoxicity of 4-HPR was not affected by ketoconazole (p ≥ 0.06). Ketoconazole increased intratumoral levels of 4-HPR (p = 0.02), of the active 4-oxo-4-HPR metabolite (p = 0.04), and intratumoral apoptosis (p ≤ 0.0006), compared to 4-HPR/LXS-alone. Concurrent ketoconazole increased EFS in both CDX models compared to 4-HPR/LXS-alone (p ≤ 0.008). 4-HPR + ketoconazole also increased EFS in PDX models compared to controls (p ≤ 0.03). Thus, concurrent ketoconazole decreased 4-HPR metabolism with resultant increases of plasma and intratumoral drug levels and antitumor effects in neuroblastoma murine xenografts. These results support the clinical testing of concurrent ketoconazole and oral fenretinide in neuroblastoma.


Assuntos
Antineoplásicos/administração & dosagem , Inibidores do Citocromo P-450 CYP3A/administração & dosagem , Fenretinida/administração & dosagem , Cetoconazol/administração & dosagem , Neuroblastoma/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linhagem Celular Tumoral , Inibidores do Citocromo P-450 CYP3A/uso terapêutico , Esquema de Medicação , Sinergismo Farmacológico , Fenretinida/uso terapêutico , Humanos , Cetoconazol/uso terapêutico , Camundongos , Resultado do Tratamento , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Br J Haematol ; 176(4): 583-590, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28055107

RESUMO

Fenretinide, a synthetic retinoid, induces apoptotic cell death in B-cell non-Hodgkin lymphoma (B-NHL) and acts synergistically with rituximab in preclinical models. We report results from a phase I-II study of fenretinide with rituximab for B-NHLs. Eligible diagnoses included indolent B-NHL or mantle cell lymphoma. The phase I design de-escalated from fenretinide at 900 mg/m2 PO BID for days 1-5 of a 7-day cycle. The phase II portion added 375 mg/m2 IV rituximab weekly on weeks 5-9 then every 3 months. Fenretinide was continued until progression or intolerance. Thirty-two patients were treated: 7 in phase I, and 25 in phase II of the trial. No dose-limiting toxicities were observed. The phase II component utilized fenretinide 900 mg/m2 twice daily with rituximab. The most common treatment-related adverse events of grade 3 or higher were rash (n = 3) and neutropenia (n = 3). Responses were seen in 6 (24%) patients on the phase II study, with a median duration of response of 47 months (95% confidence interval, 2-56). The combination of fenretinide and rituximab was well tolerated, yielded a modest overall response rate, but with prolonged remission durations. Further study should focus on identifying the responsive subset of B-NHL.


Assuntos
Fenretinida/administração & dosagem , Linfoma de Células B/tratamento farmacológico , Linfoma de Célula do Manto/tratamento farmacológico , Rituximab/administração & dosagem , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sinergismo Farmacológico , Exantema/induzido quimicamente , Feminino , Humanos , Linfoma de Células B/complicações , Linfoma de Célula do Manto/complicações , Masculino , Pessoa de Meia-Idade , Neutropenia/induzido quimicamente , Indução de Remissão
20.
Arch Virol ; 162(9): 2861-2867, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28597069

RESUMO

Biological databases contain a wealth of valuable information that can contribute to the enrichment of virtually any area. However, the exponential growth of information together with its dissemination through virtual networks has become a double-edged sword, promoting synonymy that leads to confusion and chaos. Organization of data is a big effort that must be accompanied by clarity, both in the deposited data and in the publications arising from them. In this report, an effort is made to organize the information related to infectious salmon anemia virus and its classification based on the variability of genomic segment 6.


Assuntos
Variação Genética , Genoma Viral , Isavirus/classificação , Isavirus/genética , RNA Viral/genética , Regulação Viral da Expressão Gênica , Proteínas Virais
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