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1.
J Pediatr ; 268: 113934, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38309519

RESUMO

OBJECTIVE: The objective of this study was to determine if valganciclovir initiated after 1 month of age improves congenital cytomegalovirus-associated sensorineural hearing loss. STUDY DESIGN: We conducted a randomized, double-blind, placebo-controlled phase 2 trial of 6 weeks of oral valganciclovir at US (n = 12) and UK (n = 9) sites. Patients of ages 1 month through 3 years with baseline sensorineural hearing loss were enrolled. The primary outcome was change in total ear hearing between baseline and study month 6. Secondary outcome measures included change in best ear hearing and reduction in cytomegalovirus viral load in blood, saliva, and urine. RESULTS: Of 54 participants enrolled, 35 were documented to have congenital cytomegalovirus infection and were randomized (active group: 17; placebo group: 18). Mean age at enrollment was 17.8 ± 15.8 months (valganciclovir) vs 19.5 ± 13.1 months (placebo). Twenty (76.9%) of the 26 ears from subjects in the active treatment group did not have worsening of hearing, compared with 27 (96.4%) of 28 ears from subjects in the placebo group (P = .09). All other comparisons of total ear or best ear hearing outcomes were also not statistically significant. Saliva and urine viral loads decreased significantly in the valganciclovir group but did not correlate with change in hearing outcome. CONCLUSIONS: In this randomized controlled trial, initiation of antiviral therapy beyond the first month of age did not improve hearing outcomes in children with congenital cytomegalovirus-associated sensorineural hearing loss. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT01649869.


Assuntos
Antivirais , Infecções por Citomegalovirus , Ganciclovir , Perda Auditiva Neurossensorial , Valganciclovir , Humanos , Infecções por Citomegalovirus/tratamento farmacológico , Infecções por Citomegalovirus/congênito , Infecções por Citomegalovirus/complicações , Valganciclovir/uso terapêutico , Valganciclovir/administração & dosagem , Perda Auditiva Neurossensorial/tratamento farmacológico , Perda Auditiva Neurossensorial/virologia , Perda Auditiva Neurossensorial/etiologia , Antivirais/uso terapêutico , Antivirais/administração & dosagem , Masculino , Feminino , Método Duplo-Cego , Lactente , Administração Oral , Ganciclovir/análogos & derivados , Ganciclovir/uso terapêutico , Ganciclovir/administração & dosagem , Pré-Escolar , Resultado do Tratamento , Carga Viral , Recém-Nascido
2.
Virus Res ; 340: 199291, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38065303

RESUMO

Here, the antiviral activity of aminoadamantane derivatives were evaluated against SARS-CoV-2. The compounds exhibited low cytotoxicity to Vero, HEK293 and CALU-3 cells up to a concentration of 1,000 µM. The inhibitory concentration (IC50) of aminoadamantane was 39.71 µM in Vero CCL-81 cells and the derivatives showed significantly lower IC50 values, especially for compounds 3F4 (0.32 µM), 3F5 (0.44 µM) and 3E10 (1.28 µM). Additionally, derivatives 3F5 and 3E10 statistically reduced the fluorescence intensity of SARS-CoV-2 protein S from Vero cells at 10 µM. Transmission microscopy confirmed the antiviral activity of the compounds, which reduced cytopathic effects induced by the virus, such as vacuolization, cytoplasmic projections, and the presence of myelin figures derived from cellular activation in the face of infection. Additionally, it was possible to observe a reduction of viral particles adhered to the cell membrane and inside several viral factories, especially after treatment with 3F4. Moreover, although docking analysis showed favorable interactions in the catalytic site of Cathepsin L, the enzymatic activity of this enzyme was not inhibited significantly in vitro. The new derivatives displayed lower predicted toxicities than aminoadamantane, which was observed for either rat or mouse models. Lastly, in vivo antiviral assays of aminoadamantane derivatives in BALB/cJ mice after challenge with the mouse-adapted strain of SARS-CoV-2, corroborated the robust antiviral activity of 3F4 derivative, which was higher than aminoadamantane and its other derivatives. Therefore, aminoadamantane derivatives show potential broad-spectrum antiviral activity, which may contribute to COVID-19 treatment in the face of emerging and re-emerging SARS-CoV-2 variants of concern.


Assuntos
COVID-19 , SARS-CoV-2 , Chlorocebus aethiops , Humanos , Animais , Camundongos , Ratos , Tratamento Farmacológico da COVID-19 , Células HEK293 , Células Vero , Amantadina , Antivirais/farmacologia , Antivirais/uso terapêutico
3.
Geroscience ; 44(5): 2447-2459, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36219280

RESUMO

Nipah virus (NiV) and Hendra virus (HeV) are highly pathogenic zoonotic viruses of the genus Henipavirus, family Paramyxoviridae that cause severe disease outbreaks in humans and also can infect and cause lethal disease across a broad range of mammalian species. Another related Henipavirus has been very recently identified in China in febrile patients with pneumonia, the Langya virus (LayV) of probable animal origin in shrews. NiV and HeV were first identified as the causative agents of severe respiratory and encephalitic disease in the 1990s across Australia and Southern Asia with mortality rates reaching up to 90%. They are responsible for rare and sporadic outbreaks with no approved treatment modalities. NiV and HeV have wide cellular tropism that contributes to their high pathogenicity. From their natural hosts bats, different scenarios propitiate their spillover to pigs, horses, and humans. Henipavirus-associated respiratory disease arises from vasculitis and respiratory epithelial cell infection while the neuropathogenesis of Henipavirus infection is still not completely understood but appears to arise from dual mechanisms of vascular disease and direct parenchymal brain infection. This brief review offers an overview of direct and indirect mechanisms of HeV and NiV pathogenicity and their interaction with the human immune system, as well as the main viral strategies to subvert such responses.


Assuntos
Vírus Hendra , Infecções por Henipavirus , Vírus Nipah , Humanos , Animais , Suínos , Cavalos , Saúde Pública , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/veterinária , Mamíferos
4.
Geroscience ; 44(4): 2095-2103, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35726117

RESUMO

The neglected and rare zoonotic disease caused by monkeypox virus (MPV) has recently spread widely, resulting in the largest known monkeypox outbreak outside of Africa, where it is endemic. MPV belongs to the Poxviridae family, genus Orthopoxvirus. At least two different clades have been identified, each having different fatality rates but recent cases are all phylogenetically related to the West African clade. MPV is transmitted directly by either person-to-person, -animal, or virus-contaminated fomite contact. The disease is often self-limited, and clinical symptoms include fever, skin lesions, and lymphadenopathies. At present, no deaths have been associated with the current outbreak. MPV DNA detection using molecular techniques is recommended for diagnosis. At least two approved drugs for antiviral therapy are available in the USA. Two different vaccines, including the vaccine used in the past for smallpox eradication and a new formulation more recently approved based on a live but non-replicating virus, are available that provide immunity to MPV. These and other clinical and public health considerations pertaining to the recent monkeypox outbreaks together with aspects of MPV biology are discussed in this article.


Assuntos
Mpox , Animais , Mpox/diagnóstico , Mpox/epidemiologia , Mpox/prevenção & controle , Monkeypox virus/genética , Surtos de Doenças/prevenção & controle , Febre
5.
Viral Immunol ; 35(3): 175-191, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35319302

RESUMO

Scavenger receptors (SR) are not only pattern recognition receptors involved in the immune response against pathogens but are also important receptors exploited by different virus to enter host cells, and thus represent targets for antiviral therapy. The high mutation rates of viruses, as well as their small genomes are partly responsible for the high rates of virus resistance and effective treatments remain a challenge. Most currently approved formulations target viral-encoded factors. Nevertheless, host proteins may function as additional targets. Thus, there is a need to explore and develop new strategies aiming at cellular factors involved in virus replication and host cell entry. SR-virus interactions have implications in the pathogenesis of several viral diseases and in adenovirus-based vaccination and gene transfer technologies, and may function as markers of severe progression. Inhibition of SR could reduce adenoviral uptake and improve gene therapy and vaccination, as well as reduce pathogenesis. In this review, we will examine the crucial role of SR play in cell entry of different types of human virus, which will allow us to further understand their role in protection and pathogenesis and its potential as antiviral molecules. The recent discovery of SR-B1 as co-factor of SARS-Cov-2 (severe acute respiratory syndrome coronavirus 2) entry is also discussed. Further fundamental research is essential to understand molecular interactions in the dynamic virus-host cell interplay through SR for rational design of therapeutic strategies.


Assuntos
COVID-19 , Viroses , Vírus , Humanos , Receptores Depuradores/genética , Receptores Depuradores/metabolismo , SARS-CoV-2 , Vírus/genética
6.
Eur J Pharm Sci ; 168: 106048, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34699938

RESUMO

Nanostructured lipid carriers (NLC)-loaded with lopinavir (LPV) were developed for its iontophoretic transdermal delivery. Electronic paramagnetic resonance (EPR) spectroscopy of fatty acid spin labels and differential scanning calorimetry (DSC) were applied to investigate the lipid dynamic behavior of NLC before and after the electrical current. In vitro release and permeation studies, with and without anodic and cathodic iontophoresis were also performed. NLC-LPV had nanometric size (179.0 ± 2.5 nm), high drug load (∼x223C 4.14%) and entrapment efficiency (EE) (∼x223C 80%). NLC-LPV was chemically and physically stable after applying an electric current. The electrical current reduced EE after 3 h (67.21 ± 2.64%), resulting in faster LPV in vitro release. EPR demonstrated that iontophoresis decreased NLC lipid dynamics, which is a long-lasting effect. DSC studies demonstrated that electrical current could trigger the polymorphic transition of NLC and drug solubilization in the lipid matrix. NLC-LPV, combined with iontophoresis, allowed drug quantification in the receptor medium, unlike unloaded drugs. Cathodic iontophoresis enabled the quantification of about 7.9 µg/cm2 of LPV in the receptor medium. Passive NLC-LPV studies had to be done for an additional 42 h to achieve similar concentrations. Besides, anodic iontophoresis increased by 1.8-fold the amount of LPV in the receptor medium, demonstrating a promising antiviral therapy strategy.


Assuntos
Nanopartículas , Nanoestruturas , Portadores de Fármacos , Iontoforese , Lipídeos , Lipossomos , Lopinavir , Tamanho da Partícula , Absorção Cutânea
7.
Ann Hepatol ; 27 Suppl 1: 100577, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34740846

RESUMO

INTRODUCTION AND OBJECTIVES: In 1999, a population-based survey showed a 5.6 % (102/1832) prevalence of HCV infection in O'Brien, a small rural town of Argentina. The aim of this study was to assess the impact of screening, clinical evaluation and antiviral therapy on elimination of HCV after 20 years of follow-up. PATIENTS AND METHODS: HCV+ subjects (n=102) underwent clinical, biochemical and histological evaluation to assess the presence and severity of liver disease. Antiviral therapy included pegylated interferon + ribavirin in 2005 and direct antiviral agents from 2017. RESULTS: All viremic subjects (n=84) had genotype 1b with 90%-97.5% sequence homology scores, suggesting the existence of a common source of infection (use of unsafe injections administered by the same health professional). Liver biopsy (n=55) showed chronic hepatitis in all patients. The prevalence of cirrhosis was 28% overall (29/102) and 34.5% among viremic patients. Sustained virological response (SVR) was obtained in 20/34 (59%) patients treated with interferon. From 2005 to 2017, when oral antivirals became available 37/50 untreated patients died. Median age of this group in 2005 was 67 years. Six interferon non-responders and five naive subjects received direct antiviral agents and all developed SVR. Only 1/31 patient (3.2%) with SVR died and none developed decompensated cirrhosis or HCC. In 2019, a new population-based study showed that the prevalence of HCV in O'Brien decreased 20-fold, from 5.6% to 0.28% (3/1070). CONCLUSIONS: Despite the high mortality rate precluding timely access to direct antiviral agents, the O'Brien Project is a good example of HCV micro-elimination studies.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Idoso , Antivirais/efeitos adversos , Argentina/epidemiologia , Carcinoma Hepatocelular/epidemiologia , Surtos de Doenças , Quimioterapia Combinada , Seguimentos , Hepacivirus/genética , Hepatite C/diagnóstico , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C Crônica/diagnóstico , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/epidemiologia , Humanos , Neoplasias Hepáticas/epidemiologia , Ribavirina/uso terapêutico
8.
Pharmaceuticals (Basel) ; 14(12)2021 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-34959612

RESUMO

Given the limited therapeutic management of infectious diseases caused by viruses, such as influenza and SARS-CoV-2, the medicinal use of essential oils obtained from Eucalyptus trees has emerged as an antiviral alternative, either as a complement to the treatment of symptoms caused by infection or to exert effects on possible pharmacological targets of viruses. This review gathers and discusses the main findings on the emerging role and effectiveness of Eucalyptus essential oil as an antiviral agent. Studies have shown that Eucalyptus essential oil and its major monoterpenes have enormous potential for preventing and treating infectious diseases caused by viruses. The main molecular mechanisms involved in the antiviral activity are direct inactivation, that is, by the direct binding of monoterpenes with free viruses, particularly with viral proteins involved in the entry and penetration of the host cell, thus avoiding viral infection. Furthermore, this review addresses the coadministration of essential oil and available vaccines to increase protection against different viruses, in addition to the use of essential oil as a complementary treatment of symptoms caused by viruses, where Eucalyptus essential oil exerts anti-inflammatory, mucolytic, and spasmolytic effects in the attenuation of inflammatory responses caused by viruses, in particular respiratory diseases.

9.
Clin Immunol ; 233: 108888, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34798238

RESUMO

Human interferon alpha (hIFN-α) administration constitutes the current FDA approved therapy for chronic Hepatitis B and C virus infections. Additionally, hIFN-α treatment efficacy was recently demonstrated in patients with COVID-19. Thus, hIFN-α constitutes a therapeutic alternative for those countries where vaccination is inaccessible and for people who did not respond effectively to vaccination. However, hIFN-α2b exhibits a short plasma half-life resulting in the occurrence of severe side effects. To optimize the cytokine's pharmacokinetic profile, we developed a hyperglycosylated IFN, referred to as GMOP-IFN. Given the significant number of reports showing neutralizing antibodies (NAb) formation after hIFN-α administration, here we applied the DeFT (De-immunization of Functional Therapeutics) approach to develop functional, de-immunized versions of GMOP-IFN. Two GMOP-IFN variants exhibited significantly reduced ex vivo immunogenicity and null antiproliferative activity, while preserving antiviral function. The results obtained in this work indicate that the new de-immunized GMOP-IFN variants constitute promising candidates for antiviral therapy.


Assuntos
Hepatite B Crônica/imunologia , Hepatite C Crônica/imunologia , Interferon-alfa/imunologia , Proteínas Recombinantes/imunologia , Adulto , Sequência de Aminoácidos , Animais , Anticorpos Neutralizantes/imunologia , Antivirais/imunologia , Antivirais/farmacologia , Células CHO , COVID-19/imunologia , COVID-19/virologia , Bovinos , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cricetinae , Cricetulus , Estabilidade de Medicamentos , Células HEK293 , Hepatite B Crônica/tratamento farmacológico , Hepatite B Crônica/virologia , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/genética , Interferon-alfa/farmacologia , Proteínas Recombinantes/farmacologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , SARS-CoV-2/fisiologia , Tratamento Farmacológico da COVID-19
10.
Front Immunol ; 12: 796855, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975904

RESUMO

Since its appearance, the Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2), the causal agent of Coronavirus Disease 2019 (COVID-19), represents a global problem for human health that involves the host lipid homeostasis. Regarding, lipid rafts are functional membrane microdomains with highly and tightly packed lipid molecules. These regions enriched in sphingolipids and cholesterol recruit and concentrate several receptors and molecules involved in pathogen recognition and cellular signaling. Cholesterol-rich lipid rafts have multiple functions for viral replication; however, their role in SARS-CoV-2 infection remains unclear. In this review, we discussed the novel evidence on the cholesterol-rich lipid rafts as a platform for SARS-CoV-2 entry, where receptors such as the angiotensin-converting enzyme-2 (ACE-2), heparan sulfate proteoglycans (HSPGs), human Toll-like receptors (TLRs), transmembrane serine proteases (TMPRSS), CD-147 and HDL-scavenger receptor B type 1 (SR-B1) are recruited for their interaction with the viral spike protein. FDA-approved drugs such as statins, metformin, hydroxychloroquine, and cyclodextrins (methyl-ß-cyclodextrin) can disrupt cholesterol-rich lipid rafts to regulate key molecules in the immune signaling pathways triggered by SARS-CoV-2 infection. Taken together, better knowledge on cholesterol-rich lipid rafts in the SARS-CoV-2-host interactions will provide valuable insights into pathogenesis and the identification of novel therapeutic targets.


Assuntos
COVID-19/metabolismo , Colesterol/metabolismo , Microdomínios da Membrana/metabolismo , SARS-CoV-2/metabolismo , Glicoproteína da Espícula de Coronavírus/metabolismo , COVID-19/prevenção & controle , COVID-19/virologia , Humanos , Hidroxicloroquina/farmacologia , Ligação Proteica/efeitos dos fármacos , SARS-CoV-2/fisiologia , Internalização do Vírus/efeitos dos fármacos , beta-Ciclodextrinas/farmacologia
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