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1.
Case Rep Surg ; 2024: 1013445, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601320

RESUMO

Cold atmospheric plasma (CAP) has shown promising potential in promoting wound healing. This case report presents the successful application of CAP in a 42-year-old female patient with extensive wound healing disorders and superinfections following the excision of an abscess in the left thoracic region. After several failed split skin graft attempts, the implementation of CAP led to significant improvements in wound healing. This report highlights the wound healing-promoting effects of CAP and discusses its potential mechanisms of action.

2.
Antiviral Res ; 225: 105840, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38438015

RESUMO

Host targeting antiviral drugs (HTA) are directed against cellular mechanisms which can be exploited by viruses. These mechanisms are essential for viral replication, because missing functions cannot be compensated by the virus. However, this assumption needs experimental proof. Here we compared the HTA Zapnometinib (ZMN), with direct acting antivirals (DAA) (Remdesivir (RDV), Molnupiravir (MPV), Nirmatrelvir (NTV), Ritonavir (RTV), Paxlovid PAX)), in terms of their potency to induce reduced drug susceptibilities in SARS-CoV-2. During serial passage of δ-B1.617.2 adaptation to all DAAs occurred, while the inhibitory capacity of ZMN was not altered. Known single nucleotide polymorphisms (SNPs) responsible for partial resistances were found for RDV, NTV and PAX. Additionally, the high mutagenic potential of MPV was confirmed and decreased drug efficacies were found for the first time. Reduced DAA efficacy did not alter the inhibitory potential of ZMN. These results show that ZMN confers a high barrier towards the development of viral resistance and has the potential to act against partially DAA-insensitive viruses.


Assuntos
COVID-19 , Citidina/análogos & derivados , Hepatite C Crônica , Hidroxilaminas , Humanos , Antivirais , SARS-CoV-2 , Ritonavir
3.
Front Cell Infect Microbiol ; 13: 1264983, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37965261

RESUMO

The recent COVID-19 pandemic again highlighted the urgent need for broad-spectrum antivirals, both for therapeutic use in acute viral infection and for pandemic preparedness in general. The targeting of host cell factors hijacked by viruses during their replication cycle presents one possible strategy for development of broad-spectrum antivirals. By inhibiting the Raf/MEK/ERK signaling pathway, a central kinase cascade of eukaryotic cells, which is being exploited by numerous viruses of different virus phyla, the small-molecule MEK inhibitor zapnometinib has the potential to address this need. We here performed a side-by-side comparison of the antiviral efficacy of zapnometinib against IAV and SARS-CoV-2 to determine the concentration leading to 50% of its effect on the virus (EC50) and the concentration leading to 50% reduction of ERK phosphorylation (IC50) in a comparable manner, using the same experimental conditions. Our results show that the EC50 value and IC50 value of zapnometinib are indeed lower for IAV compared to SARS-CoV-2 using one representative strain for each. The results suggest that IAV's replication has a stronger dependency on an active Raf/MEK/ERK pathway and, thus, that IAV is more susceptible to treatment with zapnometinib than SARS-CoV-2. With zapnometinib's favorable outcome in a recent phase II clinical trial in hospitalized COVID-19 patients, the present results are even more promising for an upcoming phase II clinical trial in severe influenza virus infection.


Assuntos
COVID-19 , Vírus da Influenza A , Influenza Humana , Humanos , Sistema de Sinalização das MAP Quinases , SARS-CoV-2 , Influenza Humana/tratamento farmacológico , Pandemias , Replicação Viral , Transdução de Sinais , Antivirais/farmacologia , Quinases de Proteína Quinase Ativadas por Mitógeno
4.
Antiviral Res ; 209: 105475, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36423831

RESUMO

SARS-CoV-2 is the causative agent of the immune response-driven disease COVID-19 for which new antiviral and anti-inflammatory treatments are urgently needed to reduce recovery time, risk of death and long COVID development. Here, we demonstrate that the immunoregulatory kinase p38 MAPK is activated during viral entry, mediated by the viral spike protein, and drives the harmful virus-induced inflammatory responses. Using primary human lung explants and lung epithelial organoids, we demonstrate that targeting p38 signal transduction with the selective and clinically pre-evaluated inhibitors PH-797804 and VX-702 markedly reduced the expression of the pro-inflammatory cytokines IL6, CXCL8, CXCL10 and TNF-α during infection, while viral replication and the interferon-mediated antiviral response of the lung epithelial barrier were largely maintained. Furthermore, our results reveal a high level of drug synergism of both p38 inhibitors in co-treatments with the nucleoside analogs Remdesivir and Molnupiravir to suppress viral replication of the SARS-CoV-2 variants of concern, revealing an exciting and novel mode of synergistic action of p38 inhibition. These results open new avenues for the improvement of the current treatment strategies for COVID-19.


Assuntos
Antivirais , COVID-19 , Inflamação , Síndrome de COVID-19 Pós-Aguda , SARS-CoV-2 , Proteínas Quinases p38 Ativadas por Mitógeno , Humanos , Antivirais/farmacologia , Antivirais/uso terapêutico , COVID-19/complicações , Inflamação/tratamento farmacológico , Inflamação/virologia , Pulmão , Transdução de Sinais
5.
Pharmaceutics ; 14(9)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36145524

RESUMO

The coronavirus disease 2019 (COVID-19) represents a global public health burden. In addition to vaccination, safe and efficient antiviral treatment strategies to restrict the viral spread within the patient are urgently needed. An alternative approach to a single-drug therapy is the combinatory use of virus- and host-targeted antivirals, leading to a synergistic boost of the drugs' impact. In this study, we investigated the property of the MEK1/2 inhibitor ATR-002's (zapnometinib) ability to potentiate the effect of direct-acting antivirals (DAA) against SARS-CoV-2 on viral replication. Treatment combinations of ATR-002 with nucleoside inhibitors Molnupiravir and Remdesivir or 3C-like protease inhibitors Nirmatrelvir and Ritonavir, the ingredients of the drug Paxlovid, were examined in Calu-3 cells to evaluate the advantage of their combinatory use against a SARS-CoV-2 infection. Synergistic effects could be observed for all tested combinations of ATR-002 with DAAs, as calculated by four different reference models in a concentration range that was very well-tolerated by the cells. Our results show that ATR-002 has the potential to act synergistically in combination with direct-acting antivirals, allowing for a reduction in the effective concentrations of the individual drugs and reducing side effects.

6.
Pharmaceuticals (Basel) ; 15(5)2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35631357

RESUMO

For almost two years, the COVID-19 pandemic has constituted a major challenge to human health, particularly due to the lack of efficient antivirals to be used against the virus during routine treatment interventions. Multiple treatment options have been investigated for their potential inhibitory effect on SARS-CoV-2. Natural products, such as plant extracts, may be a promising option, as they have shown an antiviral activity against other viruses in the past. Here, a quantified extract of Hypericum perforatum was tested and found to possess a potent antiviral activity against SARS-CoV-2. The antiviral potency of the extract could be attributed to the naphtodianthrones hypericin and pseudohypericin, in contrast to other tested ingredients of the plant material, which did not show any antiviral activity. Hypericum perforatum and its main active ingredient hypericin were also effective against different SARS-CoV-2 variants (Alpha, Beta, Delta, and Omicron). Concerning its mechanism of action, evidence was obtained that Hypericum perforatum and hypericin may hold a direct virus-blocking effect against SARS-CoV-2 virus particles. Taken together, the presented data clearly emphasize the promising antiviral activity of Hypericum perforatum and its active ingredients against SARS-CoV-2 infections.

7.
Stem Cell Reports ; 17(4): 789-803, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35334213

RESUMO

Several studies have pointed to retinal involvement in COVID-19, yet many questions remain regarding the ability of SARS-CoV-2 to infect and replicate in retinal cells and its effects on the retina. Here, we have used human pluripotent stem cell-derived retinal organoids to study retinal infection by SARS-CoV-2. Indeed, SARS-CoV-2 can infect and replicate in retinal organoids, as it is shown to infect different retinal lineages, such as retinal ganglion cells and photoreceptors. SARS-CoV-2 infection of retinal organoids also induces the expression of several inflammatory genes, such as interleukin 33, a gene associated with acute COVID-19 and retinal degeneration. Finally, we show that the use of antibodies to block ACE2 significantly reduces SARS-CoV-2 infection of retinal organoids, indicating that SARS-CoV-2 infects retinal cells in an ACE2-dependent manner. These results suggest a retinal involvement in COVID-19 and emphasize the need to monitor retinal pathologies as potential sequelae of "long COVID."


Assuntos
COVID-19 , Enzima de Conversão de Angiotensina 2 , COVID-19/complicações , Humanos , Organoides/metabolismo , Retina , Células Ganglionares da Retina , SARS-CoV-2 , Síndrome de COVID-19 Pós-Aguda
8.
Cell Mol Life Sci ; 79(1): 65, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013790

RESUMO

Coronavirus disease 2019 (COVID-19), the illness caused by a novel coronavirus now called severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has led to more than 260 million confirmed infections and 5 million deaths to date. While vaccination is a powerful tool to control pandemic spread, medication to relieve COVID-19-associated symptoms and alleviate disease progression especially in high-risk patients is still lacking. In this study, we explore the suitability of the rapid accelerated fibrosarcoma/mitogen-activated protein kinase/extracellular signal-regulated kinase (Raf/MEK/ERK) pathway as a druggable target in the treatment of SARS-CoV-2 infections. We find that SARS-CoV-2 transiently activates Raf/MEK/ERK signaling in the very early infection phase and that ERK1/2 knockdown limits virus replication in cell culture models. We demonstrate that ATR-002, a specific inhibitor of the upstream MEK1/2 kinases which is currently evaluated in clinical trials as an anti-influenza drug, displays strong anti-SARS-CoV-2 activity in cell lines as well as in primary air-liquid-interphase epithelial cell (ALI) cultures, with a safe and selective treatment window. We also observe that ATR-002 treatment impairs the SARS-CoV-2-induced expression of pro-inflammatory cytokines, and thus might prevent COVID-19-associated hyperinflammation, a key player in COVID-19 progression. Thus, our data suggest that the Raf/MEK/ERK signaling cascade may represent a target for therapeutic intervention strategies against SARS-CoV-2 infections and that ATR-002 is a promising candidate for further drug evaluation.


Assuntos
Antivirais/farmacologia , Tratamento Farmacológico da COVID-19 , Fenamatos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , SARS-CoV-2/efeitos dos fármacos , Células A549 , Adulto , Animais , COVID-19/metabolismo , Linhagem Celular , Células Cultivadas , Chlorocebus aethiops , Citocinas/metabolismo , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , MAP Quinase Quinase 1/antagonistas & inibidores , MAP Quinase Quinase 1/metabolismo , MAP Quinase Quinase 2/antagonistas & inibidores , MAP Quinase Quinase 2/metabolismo , SARS-CoV-2/fisiologia , Células Vero , Replicação Viral/efeitos dos fármacos
9.
mBio ; 12(5): e0219621, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34488451

RESUMO

Host shutoff in influenza A virus (IAV) infection is a key process contributing to viral takeover of the cellular machinery and resulting in the downregulation of host gene expression. Analysis of nascently transcribed RNA in a cellular model that allows the functional induction of NS1 demonstrates that NS1 suppresses host transcription. NS1 inhibits the expression of genes driven by RNA polymerase II as well as RNA polymerase I-driven promoters, but not by the noneukaryotic T7 polymerase. Additionally, transcriptional termination is deregulated in cells infected with wild-type IAV. The NS1 effector domain alone is able to mediate both effects, whereas NS1 mutant GLEWN184-188RFKRY (184-188) is not. Overexpression of CPSF30 counteracts NS1-mediated inhibition of RNA polymerase II-driven reporter gene expression, but knockdown of CPSF30 expression does not attenuate gene expression. Although NS1 is associated with nuclear chromatin, superresolution microscopy demonstrates that NS1 does not colocalize with genomic DNA. Moreover, NS1 mutants and NS1 fusion proteins, unable to associate with nuclear chromatin and displaying an altered subcellular distribution are still able to attenuate reporter gene expression. However, tethering NS1 artificially to the cytoskeleton results in the loss of reporter gene inhibition. A NS1 deficient in both native nuclear localization signals (NLS) is able to inhibit gene expression as effective as wild-type NS1 when a synthetic NLS relocates it to specific structures of the nucleus. Colocalization experiments and reporter gene cotransfection experiments with a NS1 fusion guiding it to nuclear speckles suggest that the presence of NS1 in nuclear speckles seems to be essential for host shutoff. IMPORTANCE We investigated the role of IAV nonstructural protein 1 NS1 in host gene shutoff-a central feature of IAV replication. We demonstrate that the effector domain of NS1 alone mediates host gene shutoff by inhibition of host transcription and by deregulation of the polyadenylation (polyA) signal-mediated 3' termination of host transcription. NS1 mutated in amino acids 184 to 188 fails to shut off host gene expression. Knockdown of CPSF30 does not result in transcriptional attenuation. By analyzing the subcellular localization of modified NS1 proteins and relating these data to their ability to inhibit reporter gene expression, we show for the first time that the presence of NS1 in granular structures of the nucleus-representing most likely nuclear speckles-seems to be essential to mediate host gene shutoff. Thus, our data present so far unknown insights into the molecular and spatial requirements needed for IAV-NS1-mediated host shutoff.


Assuntos
Núcleo Celular/virologia , Vírus da Influenza A Subtipo H7N7/metabolismo , Influenza Humana/genética , Influenza Humana/virologia , Transcrição Gênica , Proteínas não Estruturais Virais/química , Proteínas não Estruturais Virais/metabolismo , Núcleo Celular/genética , Núcleo Celular/metabolismo , Fator de Especificidade de Clivagem e Poliadenilação/genética , Fator de Especificidade de Clivagem e Poliadenilação/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Vírus da Influenza A Subtipo H7N7/genética , Influenza Humana/metabolismo , Domínios Proteicos , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Proteínas não Estruturais Virais/genética
10.
Molecules ; 25(20)2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33096707

RESUMO

Influenza virus infections represent a major public health issue by causing annual epidemics and occasional pandemics that affect thousands of people worldwide. Vaccination is the main prophylaxis to prevent these epidemics/pandemics, although the effectiveness of licensed vaccines is rather limited due to the constant mutations of influenza virus antigenic characteristics. The available anti-influenza drugs are still restricted and there is an increasing viral resistance to these compounds, thus highlighting the need for research and development of new antiviral drugs. In this work, two semisynthetic derivatives of digitoxigenin, namely C10 (3ß-((N-(2-hydroxyethyl)aminoacetyl)amino-3-deoxydigitoxigenin) and C11 (3ß-(hydroxyacetyl)amino-3-deoxydigitoxigenin), showed anti-influenza A virus activity by affecting the expression of viral proteins at the early and late stages of replication cycle, and altering the transcription and synthesis of new viral proteins, thereby inhibiting the formation of new virions. Such antiviral action occurred due to the interference in the assembly of viral polymerase, resulting in an impaired polymerase activity and, therefore, reducing viral replication. Confirming the in vitro results, a clinically relevant ex vivo model of influenza virus infection of human tumor-free lung tissues corroborated the potential of these compounds, especially C10, to completely abrogate influenza A virus replication at the highest concentration tested (2.0 µM). Taken together, these promising results demonstrated that C10 and C11 can be considered as potential new anti-influenza drug candidates.


Assuntos
Antivirais/farmacologia , Cardenolídeos/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Influenza Humana/tratamento farmacológico , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Antivirais/química , Cardenolídeos/química , Humanos , Conformação Molecular , RNA Polimerase Dependente de RNA/metabolismo , Replicação Viral/efeitos dos fármacos
11.
PLoS Pathog ; 16(8): e1008775, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32866218

RESUMO

Small RNA viruses only have a very limited coding capacity, thus most viral proteins have evolved to fulfill multiple functions. The highly conserved matrix protein 1 (M1) of influenza A viruses is a prime example for such a multifunctional protein, as it acts as a master regulator of virus replication whose different functions have to be tightly regulated. The underlying mechanisms, however, are still incompletely understood. Increasing evidence points towards an involvement of posttranslational modifications in the spatio-temporal regulation of M1 functions. Here, we analyzed the role of M1 tyrosine phosphorylation in genuine infection by using recombinant viruses expressing M1 phosphomutants. Presence of M1 Y132A led to significantly decreased viral replication compared to wildtype and M1 Y10F. Characterization of phosphorylation dynamics by mass spectrometry revealed the presence of Y132 phosphorylation in M1 incorporated into virions that is most likely mediated by membrane-associated Janus kinases late upon infection. Molecular dynamics simulations unraveled a potential phosphorylation-induced exposure of the positively charged linker domain between helices 4 and 5, supposably acting as interaction platform during viral assembly. Consistently, M1 Y132A showed a defect in lipid raft localization due to reduced interaction with viral HA protein resulting in a diminished structural stability of viral progeny and the formation of filamentous particles. Importantly, reduced M1-RNA binding affinity resulted in an inefficient viral genome incorporation and the production of non-infectious virions that interferes with virus pathogenicity in mice. This study advances our understanding of the importance of dynamic phosphorylation as a so far underestimated level of regulation of multifunctional viral proteins and emphasizes the potential feasibility of targeting posttranslational modifications of M1 as a novel antiviral intervention.


Assuntos
Vírus da Influenza A/metabolismo , Mutação de Sentido Incorreto , Proteínas da Matriz Viral/metabolismo , Células A549 , Substituição de Aminoácidos , Animais , Cães , Feminino , Células HEK293 , Humanos , Vírus da Influenza A/genética , Células Madin Darby de Rim Canino , Masculino , Camundongos , Camundongos Transgênicos , Fosforilação , Proteínas da Matriz Viral/genética
12.
Proc Natl Acad Sci U S A ; 117(28): 16557-16566, 2020 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-32601201

RESUMO

Influenza viruses (IV) exploit a variety of signaling pathways. Previous studies showed that the rapidly accelerated fibrosarcoma/mitogen-activated protein kinase/extracellular signal-regulated kinase (Raf/MEK/ERK) pathway is functionally linked to nuclear export of viral ribonucleoprotein (vRNP) complexes, suggesting that vRNP export is a signaling-induced event. However, the underlying mechanism remained completely enigmatic. Here we have dissected the unknown molecular steps of signaling-driven vRNP export. We identified kinases RSK1/2 as downstream targets of virus-activated ERK signaling. While RSK2 displays an antiviral role, we demonstrate a virus-supportive function of RSK1, migrating to the nucleus to phosphorylate nucleoprotein (NP), the major constituent of vRNPs. This drives association with viral matrix protein 1 (M1) at the chromatin, important for vRNP export. Inhibition or knockdown of MEK, ERK or RSK1 caused impaired vRNP export and reduced progeny virus titers. This work not only expedites the development of anti-influenza strategies, but in addition demonstrates converse actions of different RSK isoforms.


Assuntos
Vírus da Influenza A/metabolismo , Influenza Humana/virologia , Ribonucleoproteínas/metabolismo , Transporte Ativo do Núcleo Celular , Núcleo Celular/metabolismo , Núcleo Celular/virologia , Humanos , Vírus da Influenza A/genética , Influenza Humana/genética , Influenza Humana/metabolismo , Sistema de Sinalização das MAP Quinases , Sinais de Exportação Nuclear , Ribonucleoproteínas/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/genética , Proteínas Quinases S6 Ribossômicas 90-kDa/metabolismo , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo
13.
Antiviral Res ; 178: 104806, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32304723

RESUMO

Antiviral therapies against influenza are required, especially for high-risk patients, severe influenza and in case of highly pathogenic influenza virus (IV) strains. However, currently, licensed drugs that target the virus directly are not very effective and often lead to the development of resistant IV variants. This may be overcome by targeting host cell factors that are required for IV propagation. IV induces a variety of host cell signaling cascades, such as the Raf/MEK/ERK kinase pathway. The activation of this pathway is necessary for IV propagation. MEK-inhibitors block the activation of the pathway on the bottleneck of the signaling cascade leading to impaired virus propagation. In the present study, we aimed to compare the antiviral potency and bioavailability of the MEK-inhibitor CI-1040 versus its major active metabolite ATR-002, in vitro as well as in the mouse model. In cell culture assays, an approximately 10-fold higher concentration of ATR-002 is required to generate the same antiviral activity as for CI-1040. Interestingly, we observed that considerably lower concentrations of ATR-002 were required to achieve a reduction of the viral load in vivo. Pharmacokinetic studies with ATR-002 and CI-1040 in mice have found the Cmax and AUC to be far higher for ATR-002 than for CI-1040. Our results thereby demonstrate the in vivo superiority of the active metabolite ATR-002 over CI-1040 as an antiviral agent despite its weaker cell membrane permeability. Therefore, ATR-002 is an attractive candidate for development as an efficient antiviral agent, especially given the fact that a treatment based on cellular pathway inhibition would be far less likely to lead to viral drug resistance.


Assuntos
Antivirais/farmacologia , Fenamatos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Vírus da Influenza A Subtipo H3N2/efeitos dos fármacos , Quinases de Proteína Quinase Ativadas por Mitógeno/antagonistas & inibidores , Infecções por Orthomyxoviridae/virologia , Animais , Antivirais/farmacocinética , Antivirais/uso terapêutico , Benzamidas/farmacocinética , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Linhagem Celular , Modelos Animais de Doenças , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fenamatos/farmacocinética , Fenamatos/uso terapêutico , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Vírus da Influenza A Subtipo H3N2/fisiologia , Influenza Humana/virologia , Leucócitos Mononucleares , Pulmão/virologia , Sistema de Sinalização das MAP Quinases , Masculino , Camundongos , Infecções por Orthomyxoviridae/tratamento farmacológico , Fosforilação , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
14.
Cell Microbiol ; 22(2): e13143, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31711273

RESUMO

The innate immune system, in particular the type I interferon (IFN) response, is a powerful defence against virus infections. In turn, many if not all viruses have evolved various means to circumvent, resist, or counteract this host response to ensure efficient replication and propagation. Influenza viruses are no exception to this rule, and several viral proteins have been described to possess IFN-antagonistic functions. Although the viral nonstructural protein 1 appears to be a major antagonist in influenza A and B viruses (IAV and IBV), we have previously shown that a specific motif in the IAV polymerase proteins exerts an IFN-suppressive function very early in infection. The question remained whether a similar function would also exist in IBV polymerases. Here, we show that indeed a specific amino acid position (A523) of the PB1 protein in the IBV polymerase complex confers IFN-antagonistic properties. Mutation of this position leads to enhanced activation of the IFN-mediated signalling pathway after infection and subsequent reduction of virus titres. This indicates that inhibition of innate immune responses is a conserved activity shared by polymerase proteins of IAV and IBV.


Assuntos
Vírus da Influenza B , Interferon Tipo I/antagonistas & inibidores , Proteínas do Nucleocapsídeo/imunologia , RNA Polimerase Dependente de RNA/imunologia , Proteínas Virais/imunologia , Células A549 , Animais , Chlorocebus aethiops , Células HEK293 , Interações Hospedeiro-Patógeno , Humanos , Imunidade Inata , Vírus da Influenza B/enzimologia , Vírus da Influenza B/imunologia , Influenza Humana/virologia , Células Vero
15.
J AOAC Int ; 103(2): 570-583, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31645235

RESUMO

BACKGROUND: In response to a need for accurate and reliable methods for food allergen regulatory compliance, a method for the detection and quantitation of whole egg, whole milk, peanut, and hazelnut in eight food matrices was developed and evaluated in a single-laboratory validation. The matrices include cookies, cookie dough, bread, breakfast cereal, salad dressing, ice cream, and red wine. OBJECTIVE: The method was compared with Standard Method Performance Requirements (SMPR) 2016.002 established by the AOAC Stakeholder Panel on Strategic Food Analytical Methods. METHODS: The method involves tryptic digestion of allergen proteins in food matrices incurred or spiked with allergen standards [reference materials (RMs), Standard RMs (SRMs), or in-house prepared standard] and uses labeled peptide internal standards. LC-tandem MS analysis of the signature tryptic peptides of the four allergens is performed using multiple reaction monitoring. RESULTS: For 10 allergen/matrix combinations, the method demonstrated adequate sensitivity with a minimum quantitation limit of 3 mg/kg for whole egg and 10 mg/kg for milk, peanut, and hazelnut allergens. Repeatability precision across 3 days of analyses was <17% with analytical range of 10-1000 mg/kg. Recovery from incurred and spiked matrix-matched standards varied from 60 to 118%. CONCLUSIONS: The method met the minimum performance requirements of SMPR 2016.002 for whole egg in cookies, bread, cookie dough, and salad dressing; whole milk in cookies and red wine; peanut in breakfast cereal; and hazelnut in cookies. HIGHLIGHTS: The ERP determined that the data presented met the SMPR and accordingly recommended the method to be granted First Action status. In September 2017, the Official Methods Board approved the method as First Action.


Assuntos
Hipersensibilidade Alimentar , Espectrometria de Massas em Tandem , Alérgenos/análise , Cromatografia Líquida , Análise de Alimentos , Humanos
16.
Langenbecks Arch Surg ; 404(7): 853-863, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31707466

RESUMO

BACKGROUND: ERAS guidelines recommend early removal of urinary drainage after colorectal surgery to reduce the risk of catheter-associated urinary tract infections (CAUTI). Another recommendation is the postoperative use of epidural analgesia (EA). In many types of surgery, EA was shown to increase the risk of postoperative urinary retention (POUR). This study determines the impact of early urinary catheter removal on the incidence of POUR and CAUTI under EA after colorectal surgery. METHODS: Eligible patients were scheduled for colorectal surgery within the local ERAS protocol between April 2015 and September 2016. Urinary drainage was removed on the first postoperative day while EA was still in place (early removal group (ER)). The incidences of POUR and CAUTIs were recorded prospectively. Results were compared with a historical control (CG), which was operated between October 2013 and March 2015. RESULTS: POUR occurred significantly more often in the ER (ER 7.8%; CG 2.6%), while CAUTIs were significantly less frequent in the ER (13.8%) compared with the CG (30.4%). Patients who developed POUR were characterised by a significantly higher rate of abdominoperineal resections, by a higher frequency of rectal cancer, and a higher male-to-female ratio compared with patients who did not develop POUR. CONCLUSION: Early removal of urinary drainage after colorectal surgery while EA is still in place is feasible; it reduces the incidence of CAUTI but increases the risk of POUR. Thus, screening for POUR in patients with failure to void after six to 8 h is mandatory under these clinical conditions.


Assuntos
Analgesia Epidural , Remoção de Dispositivo , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/prevenção & controle , Cateterismo Urinário , Retenção Urinária/prevenção & controle , Infecções Urinárias/prevenção & controle , Idoso , Estudos de Viabilidade , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco
17.
J Pharm Biomed Anal ; 172: 278-284, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31078064

RESUMO

The recent incidences of contaminated valsartan drug products gave rise to review the suitability of current impurity profiling workflows implemented at authorities and pharmaceutical companies. The major drawback of targeted impurity profiling, where a considerable amount of prior knowledge about possible contaminants is necessary, is the fact that unexpected impurities are overlooked easily. Here, a generic untargeted approach was applied on sartan containing drug products. The untargeted workflow allowed for the discrimination of different batches, different production sites, and differences after changes in the production process. The presented universal workflow makes use of LC-HRMS/MS and multivariate analysis for the interpretation of the data. Sartan samples contaminated with N-nitrosodimethylamine could be very well discriminated from N-nitrosodimethylamine-free samples using the procedure. Furthermore, untargeted approaches revealed two new impurities in various sartans drug products: valeramide and N,N-dimethylvaleramide.


Assuntos
Amidas/química , Contaminação de Medicamentos/prevenção & controle , Nitrosaminas/química , Valsartana/química , Bloqueadores do Receptor Tipo 1 de Angiotensina II , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos
18.
J Pharm Biomed Anal ; 172: 395-405, 2019 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-31122801

RESUMO

In July 2018 one of the bestselling antihypertensive agents valsartan manufactured in China was found to be contaminated by the "probably carcinogenic" nitrosamine N-nitrosodimethylamine (NDMA), followed by the detection of N-nitrosodiethylamine (NDEA) by us and others soon after. Our work also revealed that two additional non-nitrosamine contaminations valeramide (VLA) and N,N-dimethylvaleramide (VLA-DEM) were present in sartan tablets. Early measurements by others and us were performed by GC-MS or GC-MS/MS, which does not reach the sensitivity needed to find and quantitate trace levels of NDMA and NDEA. A highly sensitive LC-MS/MS method with APCI ionization was developed to detect and quantitate NDMA, NDEA, VLA and VLA-DIM in 152 sartan tablets from 8 structurally different sartan molecules. Good linearity for each compound could be demonstrated over calibration ranges in the lower nanograms. The assay for all substances was accurate and precise. With this method, a LLOQ of 0.00026 ppm for NDMA and 0.00013 ppm for NDEA could be achieved. NDMA, NDEA, VLA and VLA-DIM were found in 21 (13.8%), 9 (5.9%), 13 (8.6%) and 7 (4.6) % of the tablets, respectively. In addition, one candesartan product was found contaminated with NDEA. The implications of our findings for the testing of pharmaceutical products are discussed.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Valsartana/química , China , Cromatografia Líquida/métodos , Dietilnitrosamina/química , Dimetilnitrosamina/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Nitrosaminas , Espectrometria de Massas em Tandem/métodos , Poluentes Químicos da Água/química
19.
J Laparoendosc Adv Surg Tech A ; 29(8): 1000-1004, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31070500

RESUMO

Introduction: Pancreatico-colonic fistula (PCF) is a rare adverse effect secondary to severe acute or chronic pancreatitis and potentially life-threatening because of abdominal sepsis. Over-the-scope clip (OTSC®) system is a recently developed endoscopic device and has been successfully used for bleeding and perforations of the gastrointestinal tract. We hereby report a series of patients with PCFs in whom OTSC was used. Materials and Methods: From January 2011 to December 2018, we retrospectively collected data on cases of PCFs with endoscopic treatment using the OTSC system. After conservative management, the endoscopic intervention was carried out on patients in deep sedation by single skilled operators. Results: A total of 9 patients were enrolled and patients were treated with 14/6 t-type OTSC. PCF occurred secondary to chronic (n = 5) and acute pancreatitis (n = 4). There were no adverse effects related to the endoscopic procedure itself. Further endoscopic evaluation was performed 8 weeks later and revealed a successful fistula closure in 4 patients with chronic pancreatitis (80%) and in 2 patients with acute pancreatitis (50%). An insufficient fistula closure was observed in 3 cases because of dislocation of the OTSC and an additional surgical procedure was required. Conclusion: The OTSC system seems to be safe and effective in short-term management of PCFs because of acute or chronic pancreatitis in addition to the already established nonsurgical therapy. However, the OTSC closure of PCFs in patients with acute pancreatitis seems to be associated with a higher failure rate. To sum up, more evidence and long-term studies are needed to determine the criteria for the use of OTSC in closure of PCFs owing to acute or chronic pancreatitis.


Assuntos
Fístula Anastomótica/etiologia , Doenças do Colo/cirurgia , Fístula/cirurgia , Pancreatite Crônica/cirurgia , Instrumentos Cirúrgicos , Doença Aguda , Adulto , Idoso , Endoscopia Gastrointestinal , Desenho de Equipamento , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatite Crônica/complicações , Estudos Retrospectivos , Resultado do Tratamento
20.
Antiviral Res ; 157: 80-92, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29990517

RESUMO

Influenza A virus (IAV) infections are still a major global threat for humans, especially for the risk groups of young children and the elderly. Annual epidemics and sporadically occurring pandemics highlight the necessity of effective antivirals that can limit viral replication. The currently licensed antiviral drugs target viral factors and are prone to provoke viral resistance. In infected host cells IAV induces various cellular signaling cascades. The Raf/MEK/ERK signaling cascade is indispensable for IAV replication because it triggers the nuclear export of newly assembled viral ribonucleoproteins (vRNPs). Inhibition of this cascade limits viral replication. Thus, next to their potential in anti-tumor therapy, inhibitors targeting the Raf/MEK/ERK signaling cascade came into focus as potential antiviral drugs. The first licensed MEK inhibitor Trametinib (GSK-1120212) is used for treatment of malignant melanoma, being highly selective and having a promising side effect profile. Since Trametinib may be qualified for a repurposing approach that would significantly shorten development time for an anti-flu use, we evaluated its antiviral potency and mode of action. In this study, we describe that Trametinib efficiently blocks replication of different IAV subtypes in vitro and in vivo. The broad antiviral activity against various IAV strains was due to its ability to interfere with export of progeny vRNPs from the nucleus. The compound also limited hyper-expression of several cytokines. Thus, we show for the first time that a clinically approved MEK inhibitor acts as a potent anti-influenza agent.


Assuntos
Antivirais/farmacologia , Citocinas/antagonistas & inibidores , Fatores Imunológicos/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Inibidores de Proteínas Quinases/farmacologia , Piridonas/farmacologia , Pirimidinonas/farmacologia , Replicação Viral/efeitos dos fármacos , Animais , Antineoplásicos/farmacologia , Linhagem Celular , Reposicionamento de Medicamentos , Humanos , Vírus da Influenza A/crescimento & desenvolvimento
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