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Ribavirin and its analogues exhibit an in vitro antiproliferative effect in cancer cells. In this work, we studied the biological activities of a number of alkyl/aryloxymethyl derivatives of ribavirin's aglycon—1,2,4-triazole-3-carboxamide. Alkyl/arylxymethyl derivatives of 1,2,4-triazole-3-carboxamide with substitutions at the fifth or first position of the triazole ring, were synthesized and their antiproliferative and antimicrobial effects were assessed. For both series, the presence of an antiproliferative effect was investigated, and 1-alkyl/aryloxymethyl derivatives were shown an antimicrobial potential against a Gram-positive bacteria Micrococcus luteus and Gram-negative bacterium Pseudomonas aeruginosa. The obtained results showed that the n-decyloxymethyl derivatives induced leukemia cell death at low micromolar concentrations. We confirmed that n-decyloxymethyl derivatives of ribavirin inhibited the cell cycle progression and induced an accumulation of leukemia cells in the subG1-phase. The molecular docking results suggest that alkyl/aryloxymethyl derivatives may act by inhibiting translation initiation, due to interference with eIF4E assembly. The outcome results revealed that active derivatives (1- or 5-n-decyloxymethyl-1,2,4-triazole-3-carboxamides) can be considered as a lead compound for anticancer treatments. [ABSTRACT FROM AUTHOR]

Amphiphilic copolymers (ACs) are versatile systems with self-assembling and aggregating properties, enabling the formation of nanomaterials (NMs) such as micelles, vesicles, nanocapsules, and nanogels. These materials have been extensively explored for the delivery of various drugs and active compounds, enhancing the solubility and permeation of poorly water-soluble drugs into skin tissue. This improvement facilitates the treatment of skin diseases, including chronic conditions like cancer, as well as infections caused by bacteria, fungi, and viruses. This review summarizes recent applications of ACs in skin treatment, with a particular focus on their use in anti-cancer drug therapy. It covers the synthesis, classification, and characterization of ACs using various experimental techniques. Additionally, it discusses recent research on different drug delivery pathways using ACs, including encapsulation efficiency, release behavior, characteristics, applications, and responses to various chemical and physical stimuli (both in vivo and in vitro). Furthermore, this review provides a comprehensive analysis of the effects of ACs NMs on several skin diseases, highlighting their potential as alternative treatments. [ABSTRACT FROM AUTHOR]

Recently, ribavirin has demonstrated effectiveness in treating glioblastoma through intranasal administration utilizing the nose-to-brain delivery route. Enhancing ribavirin's bioavailability can be achieved by utilizing intranasal stimuli-responsive systems that create a gel on the nasal mucosa. The research examined thermosensitive, pH-sensitive, and ion-selective polymers in various combinations and concentrations, chosen in line with the current Quality by Design (QbD) approach in pharmaceutical development. Following a thorough assessment of key parameters, the optimal composition of gellan gum at 0.5%, Poloxamer 124 at 2%, and purified water with ribavirin concentration at 100 mg/mL was formulated and subjected to in vivo testing. Through experiments on male rats, the nose-to-brain penetration mechanism of the active pharmaceutical ingredient (API) was elucidated, showcasing drug accumulation in the olfactory bulbs and brain. [ABSTRACT FROM AUTHOR]

Following the advent of direct-acting antivirals (DAAs), the treatment of hepatitis C virus (HCV) infection is now rarely challenging. However, data are still limited concerning DAA use in patients affected by glucose-6-phosphate dehydrogenase deficiency (G6PDd). Based on these considerations, the goal of this study was to evaluate the effectiveness and safety of DAAs in this subpopulation. A retrospective multicenter observational study (2015–2023) was conducted on all 2754 consecutive HCV-positive patients treated with first- and second-generation all-oral DAAs, and with a G6PDd diagnosis confirmed by quantitative testing (n = 38). At the treating clinician's discretion, an enhanced clinical and laboratory follow-up was performed, generally on a monthly basis both during treatment and up to six months after the end of it. Concerning hematochemical parameters, no significant differences were found between any considered time point. In all cases, no treatment-related adverse events were reported, and virologic response rates were as expected without G6PDd. In conclusion, in a large experience which, to the best of our knowledge, is unprecedented in the literature, the treatment of HCV hepatitis with nearly all available DAAs in patients with G6PDd as a comorbidity—a common occurrence in countries such as Italy—proved to be highly effective and safe. [ABSTRACT FROM AUTHOR]

1,2,4-Triazole derivatives have a wide range of biological activities. The most well-known drug that contains 1,2,4-triazole as part of its structure is the nucleoside analogue ribavirin, an antiviral drug. Finding new nucleosides based on 1,2,4-triazole is a topical task. The aim of this study was to synthesize ribosides and deoxyribosides of 1,2,4-triazole-3-thione derivatives and test their antiviral activity against herpes simplex viruses. Three compounds from a series of synthesized mono- and disubstituted 1,2,4-triazole-3-thione derivatives were found to be substrates for E. coli purine nucleoside phosphorylase. Of six prepared nucleosides, the riboside and deoxyriboside of 3-phenacylthio-1,2,4-triazole were obtained at good yields. The yields of the disubstituted 1,2,4-triazol-3-thiones were low due to the effect of bulky substituents at the C3 and C5 positions on the selectivity of enzymatic glycosylation for one particular nitrogen atom in the triazole ring. The results of cytotoxic and antiviral studies on acyclovir-sensitive wild-type strain HSV-1/L2(TK+) and acyclovir-resistant strain (HSV-1/L2/RACV) in Vero E6 cell culture showed that the incorporation of a thiobutyl substituent into the C5 position of 3-phenyl-1,2,4-triazole results in a significant increase in the cytotoxicity of the base and antiviral activity. The highest antiviral activity was observed in the 3-phenacylthio-1-(β-D-ribofuranosyl)-1,2,4-triazole and 5-butylthio-1-(2-deoxy-β-D-ribofuranosyl)-3-phenyl-1,2,4-triazole nucleosides, with their selectivity indexes being significantly higher than that of ribavirin. It was also found that with the increasing lipophilicity of the nucleosides, the activity and toxicity of the tested compounds increased. [ABSTRACT FROM AUTHOR]

Foot-and-mouth disease virus (FMDV) belongs to the Picornaviridae family and is an important pathogen affecting cloven-hoof livestock. However, neither effective vaccines covering all serotypes nor specific antivirals against FMDV infections are currently available. In this study, we employed virtual screening to screen for secondary metabolite terpenoids targeting the RNA-dependent RNA polymerase (RdRp), or 3Dpol, of FMDV. Subsequently, we identified the potential antiviral activity of the 32 top-ranked terpenoids, revealing that continentalic acid, dehydroabietic acid (abietic diterpenoids), brusatol, bruceine D, and bruceine E (tetracyclic triterpenoids) significantly reduced cytopathic effects and viral infection in the terpenoid-treated, FMDV-infected BHK-21 cells in a dose-dependent manner, with nanomolar to low micromolar levels. The FMDV minigenome assay demonstrated that brusatol and bruceine D, in particular, effectively blocked FMDV 3Dpol activity, exhibiting IC50 values in the range of 0.37–0.39 µM and surpassing the efficacy of the antiviral drug control, ribavirin. Continentalic acid and bruceine E exhibited moderate inhibition of FMDV 3Dpol. The predicted protein–ligand interaction confirmed that these potential terpenoids interacted with the main catalytic and bystander residues of FMDV 3Dpol. Additionally, brusatol and bruceine D exhibited additive effects when combined with ribavirin. In conclusion, terpenoids from natural resources show promise for the development of anti-FMD agents. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) can cause self-limiting acute and chronic hepatitis infections, particularly in immunocompromised individuals. In developing countries, HEV is mainly transmitted via drinking contaminated water, whereas zoonotic transmission dominates the route of infection in developed countries, including Japan. Pigs are an important reservoir for HEV infection. Wild boars, which share the same genus and species as domestic pigs, are also an HEV reservoir. During our nationwide study of HEV infection in wild boar populations in Japan, a genotype 6 (HEV-6) strain, wbJHG_23, was isolated in Hyogo Prefecture in 2023. The genomic length was 7244 nucleotides, excluding the poly(A) tract. The wbJHG_23 strain exhibited the highest nucleotide identity throughout its genome with two previously reported HEV-6 strains (80.3–80.9%). Conversely, it displayed lower similarity (73.3–78.1%) with the HEV-1–5, HEV-7, and HEV-8 strains, indicating that, although closely related, the wbJHG_23 strain differs significantly from the reported HEV-6 strains and might represent a novel subtype. The wbJHG_23 strain successfully infected the human-derived cancer cell lines, PLC/PRF/5 and A549 1-1H8 cells, suggesting that HEV-6 has the potential for zoonotic infection. An infectious cDNA clone was constructed using a reverse genetics system, and a cell culture system supporting the efficient propagation of the HEV-6 strain was established, providing important tools for further studies on this genotype. Using this cell culture system, we evaluated the sensitivity of the wbJHG_23 strain to ribavirin treatment. Its good response to this treatment suggested that it could be used to treat human infections caused by HEV-6. [ABSTRACT FROM AUTHOR]

Background: The risk of hepatocarcinoma in HCV cirrhotic patient responders after treatment with DAAs decrease, but HCC still occurs. A correlation between specific miRNAs and the development of hepatocarcinoma have been highlighted. Aim: To investigate miRNA expression in HCV-infected cirrhotic patients treated with DAAs, regarding whether or not they developed HCC at follow-up. Methods: A total of 73 outpatients with HCV-related cirrhosis treated with DAAs were enrolled, 28 of which had HCC. Samples were collected at the start and at the end of treatment. In the screening phase, 172 miRNAs were analyzed at baseline. Differentially expressed miRNAs were validated in the entire cohort. Results: In the validation phase, at baseline and in patients treated for 12 weeks, miR-28-5p was confirmed to be more highly expressed in the HCC group compared to the non-HCC group. In all of the patients treated for 12 weeks, at end of the treatment we found a significant downregulation in miR-132-3p, miR-133b-3p, miR-221-3p and miR-324-3p. In the HCC group, miR-28-5p was significantly downregulated after DAA therapy as well as in HCC patients treated for 24 weeks. Conclusion: In the HCC group, miR28-5p was differently expressed both at baseline and at the end of therapy with DAAs. This difference in expression should suggest its involvement in HCC development. [ABSTRACT FROM AUTHOR]

The emergence of new SARS-CoV-2 variants can affect vaccine efficacy, laboratory diagnosis and the therapies already available, triggering interest in the search for antiviral agents for SARS-CoV-2 infections. Ribavirin (RBV) is a broad-spectrum antiviral with demonstrated in vitro activity against multiple viruses, including SARS-CoV-2. This retrospective study evaluated the dynamics and viral clearance of SARS-CoV-2 in hospitalised adult participants (PTs) with COVID-19 pneumonia who received an RBV aerosol within a compassionate use study. The impact of RBV on the clinical outcome and the mutational profile of SARS-CoV-2 was also assessed. The median RNA values measured in nine PTs included in this study decreased from baseline to discharge (at BL, threshold cycle (Ct) = 22.4, IQR 19.84–5.07; at discharge, Ct = 27.92, IQR 26.43–36.11), with a significant decline in the Ct value evaluated by Friedman rank ANOVA analysis, p = 0.032. Seven out of nine PTs experienced a clinical improvement, while two PTs deceased during hospitalisation. In PTs with a favourable outcome, the virus clearance rate at discharge was 28.6%. The cumulative clearance rate was 71.4% within 14 days from discharge. A mutational pattern after RBV was detected in three out of five PTs in whom whole-genome sequencing was available. Our findings suggest that RBV limits SARS-CoV-2 replication, possibly resulting in a favourable clinical outcome. Ribavirin may also contribute to the mutational spectrum of SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Acute pneumonia (AP), triggered primarily by pathogens like bacteria and viruses, is a leading cause of human mortality. Ribavirin, a broad-spectrum antiviral agent, plays a pivotal role in the treatment of AP. However, its therapeutic use is hindered by the need for high dosages and the associated cardiac and hepatic toxicities. In this study, we synthesized polyethylene glycol-modified cationic liposomes to encapsulate ribavirin (RBV-PCL) and formulated it into a spray, aiming to enhance the effectiveness of RBV through respiratory administration. Lipopolysaccharide (LPS), a compound known to induce AP models in animals, was utilized in our research. Successfully, we established an acute pneumonia model in mice using aerosol inhalation. Through animal experiments, we investigated the therapeutic effects of RBV-PCL on mice with AP. In vivo studies revealed promising results. RBV-PCL effectively prolonged the survival of mice with AP, significantly reduced the levels of inflammatory markers such as interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α), and inhibited the infiltration of neutrophils in the lungs and spleens of mice. These findings suggest that RBV-PCL can effectively suppress the inflammatory response in mice with AP, thus holding significant potential as a novel therapeutic approach for the treatment of acute pneumonia. [ABSTRACT FROM AUTHOR]

Orthobunyavirus is the largest and most diverse genus in the family Peribunyaviridae. Orthobunyaviruses are widely distributed globally and pose threats to human and animal health. Ebinur Lake virus (EBIV) is a newly classified Orthobunyavirus detected in China, Russia, and Kenya. This study explored the antiviral effects of two broad-spectrum antiviral drugs, favipiravir and ribavirin, in a BALB/c mouse model. Favipiravir significantly improved the clinical symptoms of infected mice, reduced viral titer and RNA copies in serum, and extended overall survival. The median survival times of mice in the vehicle- and favipiravir-treated groups were 5 and 7 days, respectively. Favipiravir significantly reduced virus titers 10- to 100-fold in sera at all three time points compared to vehicle-treated mice. And favipiravir treatment effectively reduced the virus copies by approximately 10-fold across the three time points, relative to vehicle-treated mice. The findings expand the antiviral spectrum of favipiravir for orthobunyaviruses in vivo. [ABSTRACT FROM AUTHOR]

This review article describes the current knowledge about the use of antiviral chemotherapeutics in avian species, such as farm poultry and companion birds. Specific therapeutics are described in alphabetical order including classic antiviral drugs, such as acyclovir, abacavir, adefovir, amantadine, didanosine, entecavir, ganciclovir, interferon, lamivudine, penciclovir, famciclovir, oseltamivir, ribavirin, and zidovudine, repurposed drugs, such as ivermectin and nitazoxanide, which were originally used as antiparasitic drugs, and some others substances showing antiviral activity, such as ampligen, azo derivates, docosanol, fluoroarabinosylpyrimidine nucleosides, and novel peptides. Most of them have only been used for research purposes and are not widely used in clinical practice because of a lack of essential pharmacokinetic and safety data. Suggested future research directions are also highlighted. [ABSTRACT FROM AUTHOR]

Olive quick decline syndrome (OQDS) is a devastating plant disease caused by the bacterium Xylella fastidiosa (Xf). Exploratory missions in the Salento area led to the identification of putatively Xf-resistant olive trees (putatively resistant plants, PRPs) which were pauci-symptomatic or asymptomatic infected plants belonging to different genetic clusters in orchards severely affected by OQDS. To investigate the defense strategies employed by these PRPs to contrast Xf infection, the PRPs were analyzed for the anatomy and histology of xylem vessels, patterns of Xf distribution in host tissues (by the fluorescent in situ hybridization technique—FISH) and the presence of secondary metabolites in stems. The xylem vessels of the PRPs have an average diameter significantly lower than that of susceptible plants for each annual tree ring studied. The histochemical staining of xylem vessels highlighted an increase in the lignin in the parenchyma cells of the medullary rays of the wood. The 3D images obtained from FISH-LSM (laser scanning microscope) revealed that, in the PRPs, Xf cells mostly appeared as individual cells or as small aggregates; in addition, these bacterial cells looked to be incorporated in the autofluorescence signal of gels and phenolic compounds regardless of hosts' genotypes. In fact, the metabolomic data from asymptomatic PRP stems showed a significant increase in compounds like salicylic acid, known as a signal molecule which mediates host responses upon pathogen infection, and luteolin, a naturally derived flavonoid compound with antibacterial properties and with well-known anti-biofilm effects. Findings indicate that the xylem vessel geometry together with structural and chemical defenses are among the mechanisms operating to control Xf infection and may represent a common resistance trait among different olive genotypes. [ABSTRACT FROM AUTHOR]

Feline infectious peritonitis (FIP) is a multisystemic, generally lethal immuno-inflammatory disease of domestic cats caused by an infection with a genetic variant of feline coronavirus, referred to as the FIP virus (FIPV). We leveraged data from four different antiviral clinical trials performed at the University of California, Davis. Collectively, a total of 60 client-owned domestic cats, each with a confirmed diagnosis of naturally occurring FIP, were treated with a variety of antiviral compounds. The tested therapies included the antiviral compounds GS-441524, remdesivir, molnupiravir and allogeneic feline mesenchymal stem/stroma cell transfusions. Four client-owned cats with FIP did not meet the inclusion criteria for the trials and were not treated with antiviral therapies; these cats were included in the data set as untreated FIP control cats. ELISA and Western blot assays were performed using feline serum/plasma or ascites effusions obtained from a subset of the FIP cats. Normalized tissue/effusion viral loads were determined in 34 cats by a quantitative RT-PCR of nucleic acids isolated from either effusions or abdominal lymph node tissue. Twenty-one cats were PCR "serotyped" (genotyped) and had the S1/S2 region of the coronaviral spike gene amplified, cloned and sequenced from effusions or abdominal lymph node tissue. In total, 3 untreated control cats and 14 (23.3%) of the 60 antiviral-treated cats died or were euthanized during (13) or after the completion of (1) antiviral treatment. Of these 17 cats, 13 had complete necropsies performed (10 cats treated with antivirals and 3 untreated control cats). We found that anticoronaviral serologic responses were persistent and robust throughout the treatment period, primarily the IgG isotype, and focused on the viral structural Nucleocapsid and Membrane proteins. Coronavirus serologic patterns were similar for the effusions and serum/plasma of cats with FIP and in cats entering remission or that died. Viral RNA was readily detectable in the majority of the cats in either abdominal lymph node tissue or ascites effusions, and all of the viral isolates were determined to be serotype I FIPV. Viral nucleic acids in cats treated with antiviral compounds became undetectable in ascites or abdominal lymph node tissue by 11 days post-treatment using a sensitive quantitative RT-PCR assay. The most common pathologic lesions identified in the necropsied cats were hepatitis, abdominal effusion (ascites), serositis, pancreatitis, lymphadenitis, icterus and perivasculitis. In cats treated with antiviral compounds, gross and histological lesions characteristic of FIP persisted for several weeks, while the viral antigen became progressively less detectable. [ABSTRACT FROM AUTHOR]

Here, we report the in-host hepatitis E virus (HEV) quasispecies evolution in a chronically infected patient who was treated with three different regimens of ribavirin (RBV) for nearly 6 years. Sequential plasma samples were collected at different time points and subjected to RNA extraction and deep sequencing using the MiSeq Illumina platforms. Specifically, we RT-PCR amplified a single amplicon from the core region located in the open-reading frame 2 (ORF2). At the nucleotide level (genotype), our analysis showed an increase in the number of rare haplotypes and a drastic reduction in the frequency of the master (most represented) sequence during the period when the virus was found to be insensitive to RBV treatment. Contrarily, at the amino acid level (phenotype), our study revealed conservation of the amino acids, which is represented by a high prevalence of the master sequence. Our findings suggest that using mutagenic antivirals concomitant with high viral loads can lead to the selection and proliferation of a rich set of synonymous haplotypes that express the same phenotype. This can also lead to the selection and proliferation of conservative substitutions that express fitness-enhanced phenotypes. These results have important clinical implications, as they suggest that using mutagenic agents as a monotherapy treatment regimen in the absence of sufficiently effective viral inhibitors can result in diversification and proliferation of a highly diverse quasispecies resistant to further treatment. Therefore, such approaches should be avoided whenever possible. [ABSTRACT FROM AUTHOR]

Alphaviruses are serious zoonotic threats responsible for significant morbidity, causing arthritis or encephalitis. So far, no licensed drugs or vaccines are available to combat alphaviral infections. About 300,000 chikungunya virus (CHIKV) infections have been reported in 2023, with more than 300 deaths, including reports of a few cases in the USA as well. The discovery and development of small-molecule drugs have been revolutionized over the last decade. Here, we employed a cell-based screening approach using a series of in-house small-molecule libraries to test for their ability to inhibit CHIKV replication. DCR 137, a quinazoline derivative, was found to be the most potent inhibitor of CHIKV replication in our screening assay. Both, the cytopathic effect, and immunofluorescence of infected cells were reduced in a dose-dependent manner with DCR 137 post-treatment. Most importantly, DCR 137 was more protective than the traditional ribavirin drug and reduced CHIKV plaque-forming units by several log units. CHIKV-E2 protein levels were also reduced in a dose-dependent manner. Further, DCR 137 was probed for its antiviral activity against another alphavirus, the Ross River virus, which revealed effective inhibition of viral replication. These results led to the identification of a potential quinazoline candidate for future optimization that might act as a pan-alphavirus inhibitor. [ABSTRACT FROM AUTHOR]

Combining antiviral drugs with different mechanisms of action can help prevent the development of resistance by attacking the infectious agent through multiple pathways. Additionally, by using faster and more economical screening methods, effective synergistic drug candidates can be rapidly identified, facilitating faster paths to clinical testing. In this work, a rapid method was standardized to identify possible synergisms from drug combinations. We analyzed the possible reduction in the antiviral effective concentration of drugs already approved by the FDA, such as ivermectin (IVM), ribavirin (RIBA), and acyclovir (ACV) against Zika virus (ZIKV), Chikungunya virus (CHIKV), and herpes virus type 2 (HHV-2). Essential oils (EOs) were also included in the study since they have been reported for more than a couple of decades to have broad-spectrum antiviral activity. We also continued studying the antiviral properties of one of our patented molecules with broad-spectrum antiviral activity, the ferruginol analog 18-(phthalimid-2-yl)ferruginol (phthFGL), which presented an IC99 of 25.6 μM for the three types of virus. In general, the combination of IVM, phthFGL, and oregano EO showed the greatest synergism potential against CHIKV, ZIKV, and HHV-2. For instance, this combination achieved reductions in the IC99 value of each component up to ~8-, ~27-, and ~12-fold for CHIKV, respectively. The ternary combination of RIBA, phthFGL, and oregano EO was slightly more efficient than the binary combination RIBA/phthFGL but much less efficient than IVM, phthFGL, and oregano EO, which indicates that IVM could contribute more to the differentiation of cell targets (for example via the inhibition of the host heterodimeric importin IMP α/β1 complex) than ribavirin. Statistical analysis showed significant differences among the combination groups tested, especially in the HHV-2 and CHIKV models, with p = 0.0098. Additionally, phthFGL showed a good pharmacokinetic profile that should encourage future optimization studies. [ABSTRACT FROM AUTHOR]

(1) Background. Hepatitis C infection often leads to extrahepatic manifestations, including cryoglobulinemic vasculitis. This systematic review aimed to assess the efficacy and safety of rituximab in treating hepatitis C-associated cryoglobulinemic vasculitis. (2) Methods. Following PRISMA guidelines, databases were searched for relevant studies. Eligibility criteria included studies on hepatitis C-associated cryoglobulinemic vasculitis treated with rituximab. (3) Results. Nine studies met the eligibility criteria and were included in this analysis. Rituximab was commonly administered at 375 mg/m2 weekly for one month. The results consistently demonstrated the efficacy of rituximab, whether as a standalone treatment or as part of a therapeutic regimen. The combination of rituximab with Peg-IFN-α and ribavirin significantly increased the complete response rate compared to Peg-IFN-α and ribavirin alone (54.5% vs. 33.3%, p < 0.05). The 3-year sustained response rate was notably higher in the rituximab combination group (83.3% vs. 40%). In another trial, rituximab achieved remission in 83.3% of patients at 6 months, compared to only 8.3% in the control group. The efficacy of rituximab was supported by long-term experience, with clinical benefits in patients with severe cryoglobulinemic vasculitis, including those resistant to standard therapies. Mild adverse events were generally reported, with rare severe reactions in some studies. (4) Conclusions: In conclusion, rituximab appeared to be effective and safe in managing hepatitis C-associated cryoglobulinemic vasculitis, either alone or with antiviral therapy. [ABSTRACT FROM AUTHOR]

A fixed-dose combination of sofosbuvir/velpatasvir (SOF/VEL) plus weight-based ribavirin (RBV) for 12 weeks is recommended for the treatment of patients with hepatitis C virus (HCV)-associated decompensated cirrhosis. However, large global studies, while confirming the effectiveness of SOF/VEL in a broad range of patients, often exclude these patients. This Phase 2, single-arm, open-label study in adult patients with HCV-associated decompensated cirrhosis in France and the USA aimed to provide further data on the safety and efficacy of SOF/VEL plus RBV for 12 weeks in this population. Patients were treated with a fixed-dose combination of SOF 400 mg/VEL 100 mg plus weight-based RBV once daily for 12 weeks. The inclusion criteria were chronic HCV infection (≥6 months), quantifiable HCV RNA at screening, Child–Turcotte–Pugh class B or C cirrhosis, and liver imaging within 6 months of Day 1 to exclude hepatocellular carcinoma. Among 32 patients who initiated treatment, 78.1% achieved sustained virologic response 12 weeks after the end of treatment (SVR12). Failure to achieve SVR12 was due to non-virologic reasons (investigator discretion, n = 1; death, n = 6). All 25 patients in the per-protocol population achieved SVR12 and all but one achieved sustained virologic response 24 weeks after the end of treatment. Adverse events (AEs) were as expected for a patient population with advanced liver disease. All Grade 3–4 and serious AEs and deaths were deemed unrelated to treatment. In patients with HCV-associated decompensated cirrhosis, SOF/VEL plus RBV achieved high SVR12 rates and was generally well tolerated. [ABSTRACT FROM AUTHOR]

The hepatitis E virus (HEV) is increasingly acknowledged as the primary cause of acute hepatitis. While most HEV infections are self-limiting, cases of chronic infection and fulminant hepatitis necessitate the administration of anti-HEV medications. However, there is a lack of specific antiviral drugs designed for HEV, and the currently available drug (ribavirin) has been associated with significant adverse effects. The development of innovative antiviral drugs involves targeting distinct steps within the viral life cycle: the early step (attachment and internalization), middle step (translation and RNA replication), and late step (virus particle formation and virion release). We recently established three HEV reporter systems, each covering one or two of these steps. Using these reporter systems, we identified various potential drug candidates that target different steps of the HEV life cycle. Through rigorous in vitro testing using our robust cell culture system with the genotype 3 HEV strain (JE03-1760F/P10), we confirmed the efficacy of these drugs, when used alone or in combination with existing anti-HEV drugs. This underscores their significance in the quest for an effective anti-HEV treatment. In the present review, we discuss the development of the three reporter systems, their applications in drug screening, and their potential to advance our understanding of the incompletely elucidated HEV life cycle. [ABSTRACT FROM AUTHOR]

Crystallization selectivity is an important principle in polymorph control. Ribavirin Form I, Form II, DMSO solvate, and amorphous ribavirin are prepared, and the short-range order similarities between these solid forms and ribavirin aqueous solution and DMSO solution are compared via mid-frequency Raman difference spectra (MFRDS). The crystallization process from amorphous ribavirin to Form I and from solution to amorphous phase is explained. Reasons for the difficulty in preparing the DMSO solvate are proposed. The rationale provided for the crystallization selectivity provides a foundation for the synthesis of metastable phases with a robust and convenient method. [ABSTRACT FROM AUTHOR]

Apple hammerhead viroid (AHVd) was detected in the apple cultivar 'Šampion' and in mixed infection with Solanum nigrum ilarvirus 1 (SnIV-1) in the cultivars 'Selena' and 'Jonagored Supra', using a high-throughput sequencing method. Experiments were conducted to eliminate both pathogens in apples using meristem tip cultures in combination with the antivirotics ribavirin, rimantadine, and zidovudine. Elimination of both pathogens was verified by repeated RT-PCR and qRT-PCR assays after 7–11 months. Elimination of SnIV-1 from all cultivars was successful with each of the three antivirotics at concentrations of 20, 40, and 80 mg L−1. Elimination of AHVd was also achieved, although less effectively and only with ribavirin in the concentration range of 20–160 mg L−1. [ABSTRACT FROM AUTHOR]

The human respiratory syncytial virus (hRSV) is a major cause of serious lower respiratory infections and poses a considerable risk to public health globally. Only a few treatments are currently used to treat RSV infections, and there is no RSV vaccination. Therefore, the need for clinically applicable, affordable, and safe RSV prevention and treatment solutions is urgent. In this study, an ion-activated in situ gelling formulation containing the broad-spectrum antiviral 18β-glycyrrhetinic acid (GA) was developed for its antiviral effect on RSV. In this context, pH, mechanical characteristics, ex vivo mucoadhesive strength, in vitro drug release pattern, sprayability, drug content, and stability were all examined. Rheological characteristics were also tested using in vitro gelation capacity and rheological synergism tests. Finally, the cytotoxic and antiviral activities of the optimized in situ gelling formulation on RSV cultured in the human laryngeal epidermoid carcinoma (HEp-2) cell line were evaluated. In conclusion, the optimized formulation prepared with a combination of 0.5% w/w gellan gum and 0.5% w/w sodium carboxymethylcellulose demonstrated good gelation capacity and sprayability (weight deviation between the first day of the experiment (T0) and the last day of the experiment (T14) was 0.34%), desired rheological synergism (mucoadhesive force (Fb): 9.53 Pa), mechanical characteristics (adhesiveness: 0.300 ± 0.05 mJ), ex vivo bioadhesion force (19.67 ± 1.90 g), drug content uniformity (RSD%: 0.494), and sustained drug release over a period of 6 h (24.56% ± 0.49). The optimized formulation demonstrated strong anti-hRSV activity (simultaneous half maximal effective concentration (EC50) = 0.05 µg/mL; selectivity index (SI) = 306; pre-infection EC50 = 0.154 µg/mL; SI = 100), which was significantly higher than that of ribavirin (EC50 = 4.189 µg/mL; SI = 28) used as a positive control against hRSV, according to the results of the antiviral activity test. In conclusion, this study showed that nasal in situ gelling spray can prevent viral infection and replication by directly inhibiting viral entry or modulating viral replication. [ABSTRACT FROM AUTHOR]

About 5% of chronic hepatitis C (CHC) patients experienced treatment failure with direct-acting antiviral (DAA) treatment. The global data on the practice and treatment outcomes of Sofosbuvir/Velpatasvir/Voxilaprevir (SOF/VEL/VOX) in DAA-experienced CHC patients remains sparse. We performed a systematic review and meta-analysis to evaluate the efficacy and safety of SOF/VEL/VOX as a salvage treatment in DAA-experienced CHC patients. We searched five electronic databases from inception to 31 January 2023. The study outcomes were SVR12 and treatment-related adverse effects, with subgroup analysis performed based on genotype, cirrhosis, HCC, prior SOF/VEL exposure, and region. We identified and analyzed data from 24 studies (2877 DAA-experienced CHC patients); 17.2% had prior SOF/VEL exposure, 25% received ribavirin with SOF/VEL/VOX, and 42% had pre-treatment resistance-associated substitution (RAS) testing performed. Eastern Mediterranean had a higher pooled SVR12 than the America and Europe regions (p < 0.05). Predictors of SOF/VEL/VOX failure were genotype 3, active HCC, baseline cirrhosis, and prior SOF/VEL. Baseline RAS mutation and ribavirin supplementation were not associated with higher SVR12. Treatment discontinuation because of drug-related adverse events was uncommon (10 studies, 0.2%). In summary, SOF/VEL/VOX is efficacious and safe for retreatment in DAA-experienced CHC patients, even with RAS mutation. Our findings support SOF/VEL/VOX as a first-line rescue treatment for DAA-experienced CHC patients. [ABSTRACT FROM AUTHOR]

Numerous reports have explored the roles of different genetic variants in miRNA biogenesis mechanisms and the progression of various types of carcinomas. The goal of this study is to explore the association between XPO5*rs34324334 and RAN*rs14035 gene variants and susceptibility to hepatocellular carcinoma (HCC). In a cohort of 234 participants (107 HCC patients and 127 unrelated cancer-free controls) from the same geographic region, we characterized allelic discrimination using PCR-RFLP and performed subgroup analysis and multivariate regression. We found that the frequency of the XPO5*rs34324334 (A) variant was correlated with elevated risk of HCC under allelic (OR = 10.09, p-value < 0.001), recessive (OR = 24.1, p-value < 0.001), and dominant (OR = 10.1, p-value < 0.001) models. A/A genotype was associated with hepatitis C cirrhosis (p-value = 0.012), ascites (p-value = 0.003), and higher levels of alpha-fetoproteins (p-value = 0.011). Carriers of the RAN*rs14035 (T) variant were more likely to develop HCC under allelic (OR = 1.76, p-value = 0.003) and recessive (OR = 3.27, p-value < 0.001) models. Our results suggest that XPO5*rs34324334 and RAN*rs14035 variants are independent risk factors for developing HCC. [ABSTRACT FROM AUTHOR]

Among the seven coronaviruses that infect humans, HCoV-229E, HCoV-OC43, HCoV-NL63, and HCoV-HKU1 usually cause mild and common cold symptoms; however, infection with three coronaviruses, namely severe acute respiratory syndrome coronavirus [SARS-CoV], Middle East respiratory syndrome coronavirus [MERS-CoV], and the newly identified severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2], often results in respiratory distress, cytokine storm and multiorgan failure [[1]]. Group 2b SARS-like coronaviruses represent a threat to global health, as evidenced by the emergence of SARS-CoV in 2002 and SARS-CoV-2 in 2019 [[2]]. Lopinavir and ritonavir, drugs used in the treatment of HIV, were proven effective against SARS-CoV [[13]], SARS-CoV-2, and MERS-CoV [[14]] through various in vitro and animal studies. Lopinavir has been shown to inhibit SARS-CoV, MERS-CoV, and SARS-CoV-2, with EC SB 50 sb concentrations of 17.1, 8 and 26 M, respectively [[16]]. [Extracted from the article]

Respiratory Syncytial Virus (RSV) is the top cause of infant hospitalization globally, with no effective treatments available. Researchers have sought small molecules to target the RNA-dependent RNA Polymerase (RdRP) of RSV, which is essential for replication and transcription. Based on the cryo-EM structure of the RSV polymerase, in silico computational analysis including molecular docking and the protein-ligand simulation of a database, including 6554 molecules, is currently undergoing phases 1–4 of clinical trials and has resulted in the top ten repurposed compound candidates against the RSV polymerase, including Micafungin, Totrombopag, and Verubecestat. We performed the same procedure to evaluate 18 small molecules from previous studies and chose the top four compounds for comparison. Among the top identified repurposed compounds, Micafungin, an antifungal medication, showed significant inhibition and binding affinity improvements over current inhibitors such as ALS-8112 and Ribavirin. We also validated Micafungin's inhibition of the RSV RdRP using an in vitro transcription assay. These findings contribute to RSV drug development and hold promise for broad-spectrum antivirals targeting the non-segmented negative-sense (NNS) RNA viral polymerases, including those of rabies (RABV) and Ebola (EBOV). [ABSTRACT FROM AUTHOR]

Ophidian serpentoviruses, positive-sense RNA viruses in the order Nidovirales, are important infectious agents of both captive and free-ranging reptiles. Although the clinical significance of these viruses can be variable, some serpentoviruses are pathogenic and potentially fatal in captive snakes. While serpentoviral diversity and disease potential are well documented, little is known about the fundamental properties of these viruses, including their potential host ranges, kinetics of growth, environmental stability, and susceptibility to common disinfectants and viricides. To address this, three serpentoviruses were isolated in culture from three unique PCR-positive python species: Ball python (Python regius), green tree python (Morelia viridis), and Stimson's python (Antaresia stimsoni). A median tissue culture infectious dose (TCID50) was established to characterize viral stability, growth, and susceptibility. All isolates showed an environmental stability of 10–12 days at room temperature (20 °C). While all three viruses produced variable peak titers on three different cell lines when incubated at 32 °C, none of the viruses detectably replicated at 35 °C. All viruses demonstrated a wide susceptibility to sanitizers, with 10% bleach, 2% chlorhexidine, and 70% ethanol inactivating the virus in one minute and 7% peroxide and a quaternary ammonium solution within three minutes. Of seven tested antiviral agents, remdesivir, ribavirin, and NITD-008, showed potent antiviral activity against the three viruses. Finally, the three isolates successfully infected 32 unique tissue culture cell lines representing different diverse reptile taxa and select mammals and birds as detected by epifluorescent immunostaining. This study represents the first characterization of in vitro properties of growth, stability, host range, and inactivation for a serpentovirus. The reported results provide the basis for procedures to mitigate the spread of serpentoviruses in captive snake colonies as well as identify potential non-pharmacologic and pharmacologic treatment options for ophidian serpentoviral infections. [ABSTRACT FROM AUTHOR]

The total alcohol extract obtained from the aerial parts of R. stricta and fractions of the liquid–liquid fractionation process were tested against picornavirus-causing foot-and-mouth disease (FMD) based on the traditional use of the plant in Saudi Arabia. The most active petroleum ether soluble fraction was subjected to chromatographic purification, and nine compounds were isolated, identified using various chemical and spectroscopic methods, and tested for their anti-viral potential. The new ester identified as α-Amyrin 3-(3′R-hydroxy)-hexadecanoate (1) was the most active compound with 51% inhibition of the viral growth and was given the name Rhazyin A. Compounds with ursane skeleton were more active than those with lupane skeleton except in the case of the acid derivatives where betulenic acid showed 26.1% inhibition against the viral growth, while ursolic acid showed only 16.6% inhibition. Moreover, molecular docking analysis using a glide extra-precision module was utilized for investigating the possible molecular interactions accounting for anti-viral activity against picornavirus of the nine isolated compounds. Molecular docking studies revealed a strong binding of the discovered hits within the active site of FMDV 3Cpro. Compound 1 showed the lowest docking score within the nine isolated compounds comparable to the two known anti-viral drugs; glycyrrhizic acid and ribavirin. The results of this research will provide lead candidates from natural origin with potential safety and efficacy compared to the synthetic ones with lower production costs for managing FMVD. [ABSTRACT FROM AUTHOR]

Base pairing based on hydrogen bonding has, since its inception, been crucial in the antiviral activity of arabinosyladenine, 2′-deoxyuridines (i.e., IDU, TFT, BVDU), acyclic nucleoside analogues (i.e., acyclovir) and nucleoside reverse transcriptase inhibitors (NRTIs). Base pairing based on hydrogen bonding also plays a key role in the mechanism of action of various acyclic nucleoside phosphonates (ANPs) such as adefovir, tenofovir, cidofovir and O-DAPYs, thus explaining their activity against a wide array of DNA viruses (human hepatitis B virus (HBV), human immunodeficiency (HIV) and human herpes viruses (i.e., human cytomegalovirus)). Hydrogen bonding (base pairing) also seems to be involved in the inhibitory activity of Cf1743 (and its prodrug FV-100) against varicella-zoster virus (VZV) and in the activity of sofosbuvir against hepatitis C virus and that of remdesivir against SARS-CoV-2 (COVID-19). Hydrogen bonding (base pairing) may also explain the broad-spectrum antiviral effects of ribavirin and favipiravir. This may lead to lethal mutagenesis (error catastrophe), as has been demonstrated with molnutegravir in its activity against SARS-CoV-2. [ABSTRACT FROM AUTHOR]

Hepatitis A and hepatitis E are relatively common causes of liver disease. Both viruses are mainly transmitted through the faecal–oral route and, consequently, most outbreaks occur in countries with poor sanitation. An important role of the immune response as the driver of liver injury is also shared by the two pathogens. For both the hepatitis A (HAV) and hepatitis E (HEV) viruses, the clinical manifestations of infection mainly consist of an acute disease with mild liver injury, which results in clinical and laboratory alterations that are self-limiting in most cases. However, severe acute disease or chronic, long-lasting manifestations may occur in vulnerable patients, such as pregnant women, immunocompromised individuals or those with pre-existing liver disease. Specifically, HAV infection rarely results in fulminant hepatitis, prolonged cholestasis, relapsing hepatitis and possibly autoimmune hepatitis triggered by the viral infection. Less common manifestations of HEV include extrahepatic disease, acute liver failure and chronic HEV infection with persistent viraemia. In this paper, we conduct a non-systematic review of the available literature to provide a comprehensive understanding of the state of the art. Treatment mainly consists of supportive measures, while the available evidence for aetiological treatment and additional agents in severe disease is limited in quantity and quality. However, several therapeutic approaches have been attempted: for HAV infection, corticosteroid therapy has shown outcome improvement, and molecules, such as AZD 1480, zinc chloride and heme oxygenase-1, have demonstrated a reduction in viral replication in vitro. As for HEV infection, therapeutic options mainly rely on the use of ribavirin, and some studies utilising pegylated interferon-alpha have shown conflicting results. While a vaccine for HAV is already available and has led to a significant reduction in the prevalence of the disease, several vaccines for HEV are currently being developed, with some already available in China, showing promising results. [ABSTRACT FROM AUTHOR]

Self-inflicted violence is a major and growing public health problem and its prediction and prevention is challenging for healthcare systems worldwide. Our aim was to identify prescribed drugs associated with self-directed violent behaviors in Spain. A descriptive, longitudinal and retrospective study of spontaneous reports of adverse drug reactions corresponding to self-directed violence was recorded in the Spanish Pharmacovigilance Database (FEDRA®) from 1984 to 31 March 2021. A total of 710 cases were reported in the study period. The mean age was 45.52 years (range 1–94). There were no gender differences except in children, where most reports were of male children. The main therapeutic groups that were involved included drugs for the nervous system (64.5%) and anti-infectives for systemic use (13.2%). The most commonly reported drugs were varenicline, fluoxetine, lorazepam, escitalopram, venlafaxine, veralipride, pregabalin, roflumilast and bupropion. There were reports of montelukast, hydroxychloroquine, isotretinoin, methylphenidate, infliximab, natalizumab, ribavirin and efavirenz, which were less known to be involved in self-directed violence. This study shows that self-directed violence is a rare adverse drug reaction, and can be related to the use of some medicines. It is important for healthcare professionals to consider this risk in their clinical praxis, implementing person-centred approaches. Further studies are needed, considering comorbidities and potential interactions. [ABSTRACT FROM AUTHOR]

Hepatitis E is a zoonosis caused by hepatitis E virus (HEV), which was first discovered 40 years ago. Twenty million HEV infections worldwide are estimated each year. Most hepatitis E cases are self-limiting acute hepatitis, but the virus has been recognized to cause chronic hepatitis. Following the first case report of chronic hepatitis E (CHE) in a transplant recipient, CHE has recently been identified as associated with chronic liver damage induced by HEV genotypes 3, 4, and 7—usually in immunocompromised patients such as transplant recipients. In addition, patients infected with HIV and those receiving chemotherapy for malignancy, along with patients with rheumatic disease and COVID-19, have recently been reported as having CHE. CHE can be easily misdiagnosed by usual diagnostic methods of antibody response, such as anti-HEV IgM or IgA, because of the low antibody response in the immunosuppressive condition. HEV RNA should be evaluated in these patients, and appropriate treatments—such as ribavirin—should be given to prevent progression to liver cirrhosis or liver failure. While still rare, cases of CHE in immunocompetent patients have been reported, and care must be taken not to overlook these instances. Herein, we conduct an overview of hepatitis E, including recent research developments and management of CHE, in order to improve our understanding of such cases. The early diagnosis and treatment of CHE should be performed to decrease instances of hepatitis-virus-related deaths around the world. [ABSTRACT FROM AUTHOR]

Plant diseases and insect pests seriously affect the yield and quality of crops and are difficult to control. Natural products are an important source for the discovery of new pesticides. In this work, naphthoquinones plumbagin and juglone were selected as parent structures, and a series of their derivatives were designed, synthesized and evaluated for their fungicidal activities, antiviral activities and insecticidal activities. We found that the naphthoquinones have broad-spectrum anti-fungal activities against 14 types of fungus for the first time. Some of the naphthoquinones showed higher fungicidal activities than pyrimethanil. Compounds I, I-1e and II-1a emerged as new anti-fungal lead compounds with excellent fungicidal activities (EC50 values: 11.35–17.70 µg/mL) against Cercospora, arachidicola Hori. Some compounds also displayed good to excellent antiviral activities against the tobacco mosaic virus (TMV). Compounds I-1f and II-1f showed similar level of anti-TMV activities with ribavirin, and could be used as new antiviral candidates. These compound also exhibited good to excellent insecticidal activities. Compounds II-1d and III-1c displayed a similar level of insecticidal activities with matrine, hexaflumuron and rotenone against Plutella xylostella. In current study, plumbagin and juglone were discovered as parent structures, which lays a foundation for their application in plant protection. [ABSTRACT FROM AUTHOR]

The latest monkeypox virus outbreak in 2022 showcased the potential threat of this viral zoonosis to public health. The lack of specific treatments against this infection and the success of viral protease inhibitors-based treatments against HIV, Hepatitis C, and SARS-CoV-2, brought the monkeypox virus I7L protease under the spotlight as a potential target for the development of specific and compelling drugs against this emerging disease. In the present work, the structure of the monkeypox virus I7L protease was modeled and thoroughly characterized through a dedicated computational study. Furthermore, structural information gathered in the first part of the study was exploited to virtually screen the DrugBank database, consisting of drugs approved by the Food and Drug Administration (FDA) and clinical-stage drug candidates, in search for readily repurposable compounds with similar binding features as TTP-6171, the only non-covalent I7L protease inhibitor reported in the literature. The virtual screening resulted in the identification of 14 potential inhibitors of the monkeypox I7L protease. Finally, based on data collected within the present work, some considerations on developing allosteric modulators of the I7L protease are reported. [ABSTRACT FROM AUTHOR]

Viruses with rapid replication and easy mutation can become resistant to antiviral drug treatment. With novel viral infections emerging, such as the recent COVID-19 pandemic, novel antiviral therapies are urgently needed. Antiviral proteins, such as interferon, have been used for treating chronic hepatitis C infections for decades. Natural-origin antimicrobial peptides, such as defensins, have also been identified as possessing antiviral activities, including direct antiviral effects and the ability to induce indirect immune responses to viruses. To promote the development of antiviral drugs, we constructed a data repository of antiviral peptides and proteins (DRAVP). The database provides general information, antiviral activity, structure information, physicochemical information, and literature information for peptides and proteins. Because most of the proteins and peptides lack experimentally determined structures, AlphaFold was used to predict each antiviral peptide's structure. A free website for users (http://dravp.cpu-bioinfor.org/ , accessed on 30 August 2022) was constructed to facilitate data retrieval and sequence analysis. Additionally, all the data can be accessed from the web interface. The DRAVP database aims to be a useful resource for developing antiviral drugs. [ABSTRACT FROM AUTHOR]

5-Amino-1-β-D-ribofuranosylimidazole-4-carboxamide 5′-monophosphate (ZMP) is a central intermediate in de novo purine nucleotide biosynthesis. Its nucleobase moiety, 5-aminoimidazole-4-carboxamide (Z-base), is considered an ambiguous base that can pair with any canonical base owing to the rotatable nature of its 5-carboxamide group. This idea of ambiguous base pairing due to free rotation of the carboxamide has been applied to designing mutagenic antiviral nucleosides, such as ribavirin and T-705. However, the ambiguous base-pairing ability of Z-base has not been elucidated, because the synthesis of Z-base-containing oligomers is problematic. Herein, we propose a practical method for the synthesis of Z-base-containing DNA oligomers based on the ring-opening reaction of an N1-dinitrophenylhypoxanthine (HxaDNP) base. Thermal denaturation studies of the resulting oligomers revealed that the Z-base behaves physiologically as an A-like nucleobase, preferentially forming pairs with T. We tested the behavior of Z-base-containing DNA oligomers in enzyme-catalyzed reactions: in single nucleotide insertion, Klenow fragment DNA polymerase recognized Z-base as an A-like analog and incorporated dTTP as a complementary nucleotide to Z-base in the DNA template; in PCR amplification, Taq DNA polymerase similarly incorporated dTTP as a complementary nucleotide to Z-base. Our findings will contribute to the development of new mutagenic antiviral nucleoside analogs. [ABSTRACT FROM AUTHOR]

Pesticides are essential for the development of agriculture. It is urgent to develop green, safe and efficient pesticides. Bisindole alkaloids have unique and concise structures and broad biological activities, which make them an important leading skeleton in the creation of new pesticides. In this work, we synthesized bisindole alkaloid barakacin in a simple seven-step process, and simultaneously designed and synthesized a series of its derivatives. Biological activity research indicated that most of these compounds displayed good antiviral activities against tobacco mosaic virus (TMV). Among them, compound 14b exerted a superior inhibitory effect in comparison to commercially available antiviral agent ribavirin, and could be expected to become a novel antiviral candidate. Molecular biology experiments and molecular docking research found that the potential target of compound 14b was TMV coat protein (CP). These compounds also showed broad-spectrum anti-fungal activities against seven kinds of plant fungi. [ABSTRACT FROM AUTHOR]

Antiretroviral therapies (ART) are strongly associated with weight gain and metabolic syndrome (MetS) development in HIV-infected patients. Few studies have evaluated the association between gut microbiota and integrase strand transfer inhibitor (INSTI)-based and protease inhibitor (PI)-based regimens in HIV-infected patients with MetS. To assess this, fecal samples were obtained from HIV-infected patients treated with different regimens (16 PI + MetS or 30 INSTI + MetS) and 18 healthy controls (HCs). The microbial composition was characterized using 16S rRNA amplicon sequencing. The INSTI-based and PI-based regimens were associated with a significant decrease in α-diversity compared to HCs. The INSTI + MetS group showed the lowest α-diversity between both regimens. A significant increase in the abundance of short-chain fatty acid (SCFA)-producing genera (Roseburia, Dorea, Ruminococcus torques, and Coprococcus) was observed in the PI + MetS group, while Prevotella, Fusobacterium, and Succinivibrio were significantly increased in the INSTI + MetS group. Moreover, the Proteobacteria/Firmicutes ratio was overrepresented, and functional pathways related to the biosynthesis of LPS components were increased in the INSTI + MetS group. The gut microbiota of patients receiving INSTIs showed a more pronounced dysbiosis orchestrated by decreased bacterial richness and diversity, with an almost complete absence of SCFA-producing bacteria and alterations in gut microbiota functional pathways. These findings have not been previously observed. [ABSTRACT FROM AUTHOR]

Background: Seeing that there are no data about associations between serotonin gene polymorphism and tryptophan catabolite concentration during PEG-IFN-α2a treatment, the aim of the current study is to examine (a) the associations between polymorphisms within the HTR1A, TPH2, and 5-HTT genes and the severity of depression symptoms and (b) the relationships among rs6295, rs4570625, and 5-HTTLPR rs25531polymorphisms and indoleamine 2,3-dioxygenase (IDO) activity, as well as kynurenine (KYN), tryptophan (TRP), kynurenic acid (KA), and anthranilic acid (AA) concentrations. Materials and methods: The study followed a prospective, longitudinal, single-center cohort design. The severity of the depressive symptoms of 101 adult patients with chronic HCV infections was measured during PEG-IFN-α2a/RBV treatment. We used the Montgomery–Åsberg Depression Rating Scale (MADRS) to assess the severity of depressive symptoms. The subjects were evaluated six times—at baseline and at weeks 2, 4, 8, 12, and 24. At all the time points, MADRS score, as well as KYN, TRP, KA, and AA concentrations, and IDO activity were measured. At baseline, rs6295, rs4570625, and 5-HTTLPR rs25531polymorphisms were assessed. Results: Subjects with C/C genotypes of 5-HT1A and lower-expressing alleles (S/S, LG/LG, and S/LG) of 5-HTTLPR scored the highest total MADRS scores and recorded the highest increase in MADRS scores during treatment. We found associations between TRP concentrations and the TPH-2 and 5-HTTLPR rs25531 genotypes. Conclusions: Our findings provide new data that we believe can help better understand infection-induced depression as a distinct type of depression. [ABSTRACT FROM AUTHOR]

Direct-acting antivirals (DAA) regimens have provided hope for eliminating hepatitis C virus (HCV) infection. Patients following ineffective therapy with DAA, especially those previously treated with inhibitors of non-structural protein 5A (NS5A), remain a challenge. The study aimed to assess the effectiveness of DAA pangenotypic options in patients after failure of NS5A containing genotype-specific regimens. The analysis included 120 patients selected from the EpiTer-2 database with data on 15675 HCV-infected individuals treated with IFN-free therapies from 1 July 2015 to 30 June 2022 at 22 Polish hepatology centres. The majority of them were infected with genotype (GT) 1b (85.8%) and one-third was diagnosed with fibrosis F4. Among the rescue pangenotypic regimens, the most commonly used was the sofosbuvir/velpatasvir (SOF/VEL) ± ribavirin (RBV) combination. The sustained virologic response, which was a measure of treatment effectiveness, was achieved by 102 patients, resulting in cure rate of 90.3% in the per protocol analysis. All 11 non-responders were infected with GT1b, 7 were diagnosed with cirrhosis, and 9 were treated with SOF/VEL±RBV. We demonstrated the high effectiveness of the pangenotypic rescue options in patients after genotype specific NS5A-containing regimens failures, identifying cirrhosis as a negative prognostic factor of treatment effectiveness. [ABSTRACT FROM AUTHOR]

Background: Hepatocellular carcinoma (HCC) tends to recur after curative treatment. This study aimed to identify the clinical factors associated with HCC recurrence after initial curative therapy. Methods: We retrospectively included patients with early stage HCC Barcelona Clinic Liver Cancer (BCLC) stages 0 and A who received curative surgical resection or local ablation at three different Chang Gung Memorial Hospitals in Taiwan (527 patients from Linkou, 150 patients from Keelung, and 127 patients from Chiayi) from 2000 to 2009. Pretreatment clinical data were subjected to univariate and multivariate logistic analyses to identify the risk factors for HCC recurrence within five years after the primary curative treatment. Recurrence and survival rates were assessed using Kaplan–Meier curves and log-rank tests. Results: Patients with a history of nucleoside analog or peg-interferon treatment for hepatitis B or hepatitis C infection had lower HCC recurrence rates than did those without such treatment. By contrast, alcohol drinking habits (p = 0.0049, hazard ratio (HR): 1.508, 95%CI: 1.133–2.009), a platelet count of < 14 × 104/μL (p = 0.003, HR: 1.533, 95%CI: 1.155–2.035), and a serum alanine aminotransferase level > 40 U/L (p = 0.0450, HR: 1.305, 95%CI: 1.006–1.694) were independent risk factors for HCC recurrence. The five-year HCC recurrence rates did not differ between patients who received either local radiofrequency ablation or surgical resection at BCLC stages 0 and A. Conclusions: Factors contributing to persistent hepatitis activity and advanced fibrosis precipitate tumor recurrence. Active intervention to discontinue liver injury or hepatitis could reduce HCC recurrence. [ABSTRACT FROM AUTHOR]

Respiratory viruses represent a world public health problem, giving rise to annual seasonal epidemics and several pandemics caused by some of these viruses, including the COVID-19 pandemic caused by the novel SARS-CoV-2, which continues to date. Some antiviral drugs have been licensed for the treatment of influenza, but they cause side effects and lead to resistant viral strains. Likewise, aerosolized ribavirin is the only drug approved for the therapy of infections by the respiratory syncytial virus, but it possesses various limitations. On the other hand, no specific drugs are licensed to treat other viral respiratory diseases. In this sense, natural products and their derivatives have appeared as promising alternatives in searching for new compounds with antiviral activity. Besides their chemical properties, quinones have demonstrated interesting biological activities, including activity against respiratory viruses. This review summarizes the activity against respiratory viruses and their molecular targets by the different types of quinones (both natural and synthetic). Thus, the present work offers a general overview of the importance of quinones as an option for the future pharmacological treatment of viral respiratory infections, subject to additional studies that support their effectiveness and safety. [ABSTRACT FROM AUTHOR]

Hepatitis E virus (HEV) is a major cause of acute hepatitis globally. Chronic and fulminant courses are observed especially in immunocompromised transplant recipients since administration of ribavirin (RBV) does not always lead to a sustained virologic response. By in vitro stimulation of NK cells through hepatoma cell lines inoculated with a full-length HEV and treatment with RBV, we analyzed the viral replication and cell response to further elucidate the mechanism of action of RBV on immune cells, especially NK cells, in the context of HEV infection. Co-culture of HEV-infected hepatoma cells with PBMCs and treatment with RBV both resulted in a decrease in viral replication, which in combination showed an additive effect. An analysis of NK cell functions after stimulation revealed evidence of reduced cytotoxicity by decreased TRAIL and CD107a degranulation. Simultaneously, IFN-ɣ production was significantly increased through the IL-12R pathway. Although there was no direct effect on the IL-12R subunits, downstream events starting with TYK-2 and subsequently pSTAT4 were upregulated. In conclusion, we showed that RBV has an immunomodulatory effect on the IL-12R pathway of NK cells via TYK-2. This subsequently leads to an enhanced IFN-ɣ response and thus, to an additive antiviral effect in the context of an in vitro HEV infection. [ABSTRACT FROM AUTHOR]

Puumala hantavirus (PUUV) infections usually show a mild or moderate clinical course, but may sometimes also lead to life-threatening disease. Here, we report on a 60-year-old female patient with common variable immunodeficiency (CVID) who developed a fatal PUUV infection with persistent renal failure, thrombocytopenia, and CNS infection with impaired consciousness and tetraparesis. Hantavirus-specific antibodies could not be detected due to the humoral immunodeficiency. Diagnosis and virological monitoring were based on the quantitative detection of PUUV RNA in blood, cerebrospinal fluid, bronchial lavage, and urine, where viral RNA was found over an unusually extended period of one month. Due to clinical deterioration and virus persistence, treatment with ribavirin was initiated. Additionally, fresh frozen plasma (FFP) from convalescent donors with a history of PUUV infection was administered. Despite viral clearance, the clinical condition of the patient did not improve and the patient died on day 81 of hospitalization. This case underlines the importance of the humoral immune response for the course of PUUV disease and illustrates the need for PCR-based virus diagnostics in those patients. Due to its potential antiviral activity, convalescent plasma should be considered in the therapy of severe hantavirus diseases. [ABSTRACT FROM AUTHOR]

Host regulatory immune response is involved in the hepatic inflammatory process caused by the hepatitis C virus (HCV). We aimed to determine if HCV clearance with direct-acting antivirals (DAAs) changes the hepatic fibrosis stage, biochemical parameters of liver injury, and inflammatory/immune responses. Sample: 329 chronic hepatitis C (CHC) patients, 134 of them treated with DAAs. Liver fibrosis was evaluated by transient elastography (FibroScan), biochemical and cellular parameters were determined by standard methods, cytokine concentration by enzyme-linked immunoabsorbent assay (ELISA), and genetic polymorphisms by polymerase chain reaction—restriction fragment length polymorphism (PCR-RFLP) or endpoint genotyping. Before DAA treatment, severe fibrosis or cirrhosis (F3/4) was associated with higher values of tumor necrosis factor-alpha (TNF-α) and genotypes transforming growth factor-beta-509 C/T_CC (TGF-β-509 C/T_CC), interleukine-10-1082 T/C_CC (IL-10-1082 T/C_CC), and IL-10-592 G/T_GT. After DAA treatment, fewer F3/4 patients and lower values of TNF-α were found. Patients with TNF-α-308 G/A_GG and IL-10-592 G/T_GT were at risk for F3/4. Lack of improvement of liver fibrosis was associated with lower baseline values of platelet count for genotypes TNF-α-308 G/A_GG and haplotype TT/GG of IL-10-1082 T/C and IL-10-592 G/T. Our study showed decreased liver fibrosis/inflammation and normalization of liver injury biomarkers after DAA treatment. It also points to the importance of suppressing the pro-inflammatory response by DAAs in the resolution of hepatitis C, contributing to the improvement of liver damage evaluated by transient elastography. [ABSTRACT FROM AUTHOR]

Although chronic hepatitis C has been effectively treated with direct-acting antivirals (DAAs), the use of conventional therapy with peg-interferon (Peg-IFN) or (predominantly) ribavirin (RBV), remains widespread. R70Q/H and L/C91M amino acid substitutions in the hepatitis C virus (HCV) core protein may modulate responses to IFN and/or RBV, and are associated with cirrhosis, hepatocellular carcinoma (HCC), insulin resistance, and liver steatosis. We evaluated the R70Q/H and L/C91M substitutions, clinical and epidemiological profiles, and risk factors of Brazilian patients chronically infected with HCV subgenotypes 1a and 1b (HCV-GT1a and HCV-GT1b) unresponsive to IFN and/or RBV therapy. Sequencing and pyrosequencing analyses and sociodemographic and clinical predictive variables were used to assess the relationship between R70Q/H and L/C91M substitutions. Leukocyte counts, ALT levels, and ALT/AST ratios were significantly reduced in treated individuals, but more of these patients had advanced fibrosis and cirrhosis. L91M was more prevalent (19.7%), occurring only in HCV-GT1b, followed by R70Q/P (11.5%) and R70P (1.4%). R70Q/P exhibited higher mean AST, ALT, and GGT values, whereas L91M showed higher mean GGT values. Pyrosequencing of the L91M position revealed mutant subpopulations in 43.75% of samples. [ABSTRACT FROM AUTHOR]

Lassa fever (LF) is a rodent-borne disease that threatens human health in the sub-region of West Africa where the zoonotic host of Lassa virus (LASV) is predominant. Currently, treatment options for LF are limited and since no preventive vaccine is approved for its infectivity, there is a high mortality rate in endemic areas. This narrative review explores the transmission, pathogenicity of LASV, advances, and challenges of different treatment options. Our findings indicate that genetic diversity among the different strains of LASV and their ability to circumvent the immune system poses a critical challenge to the development of LASV vaccines/therapeutics. Thus, understanding the biochemistry, physiology and genetic polymorphism of LASV, mechanism of evading host immunity are essential for development of effective LASV vaccines/therapeutics to combat this lethal viral disease. The LASV nucleoprotein (NP) is a novel target for therapeutics as it functions significantly in several aspects of the viral life cycle. Consequently, LASV NP inhibitors could be employed as effective therapeutics as they will potentially inhibit LASV replication. Effective preventive control measures, vaccine development, target validation, and repurposing of existing drugs, such as ribavirin, using activity or in silico-based and computational bioinformatics, would aid in the development of novel drugs for LF management. [ABSTRACT FROM AUTHOR]

Chronic hepatitis C virus (HCV) infections are a worldwide medical problem responsible for diverse types of liver diseases. The NS5B polymerase enzyme has become a very interesting target for the development of anti-HCV drugs owing to its fundamental role in viral replication. Here we report the synthesis of a novel series of 1-substituted phenyl-4(1H)-quinazolinone and 2-methyl-1-substituted phenyl-4(1H)-quinazolinone derivatives and evaluate their activity against HCV in HCV subgenomic replicon assays. The biological data revealed that compound 11a showed the highest activity against HCV GT1b at a micromolar concentration (EC50 = 0.984 µM) followed by compound 11b (EC50 = 1.38 µM). Both compounds 11a and 11b had high selectivity indices (SI = CC50/EC50), 160.71 and 71.75, respectively, which make them very interesting candidates for further development of more potent and selective anti-HCV agents. [ABSTRACT FROM AUTHOR]

The changes occurring in viral quasispecies populations during infection have been monitored using diversity indices, nucleotide diversity, and several other indices to summarize the quasispecies structure in a single value. In this study, we present a method to partition quasispecies haplotypes into four fractions according to their fitness: the master haplotype, rare haplotypes at two levels (those present at <0.1%, and those at 0.1–1%), and a fourth fraction that we term emerging haplotypes, present at frequencies >1%, but less than that of the master haplotype. We propose that by determining the changes occurring in the volume of the four quasispecies fitness fractions together with those of the Hill number profile we will be able to visualize and analyze the molecular changes in the composition of a quasispecies with time. To develop this concept, we used three data sets: a technical clone of the complete SARS-CoV-2 spike gene, a subset of data previously used in a study of rare haplotypes, and data from a clinical follow-up study of a patient chronically infected with HEV and treated with ribavirin. The viral response to ribavirin mutagenic treatment was selection of a rich set of synonymous haplotypes. The mutation spectrum was very complex at the nucleotide level, but at the protein (phenotypic/functional) level the pattern differed, showing a highly prevalent master phenotype. We discuss the putative implications of this observation in relation to mutagenic antiviral treatment. [ABSTRACT FROM AUTHOR]