Search Results (3,725)

Epstein–Barr virus (EBV) lytic reactivation contributes to the pathogenesis of EBV-associated epithelial malignancies, including nasopharyngeal carcinoma and gastric carcinoma, highlighting the need for therapeutic strategies targeting viral reactivation. Capsaicin exhibits anticancer and antiviral activities; however, its effects on EBV lytic reactivation remain unclear. This study investigated the effects of capsaicin on EBV lytic reactivation in EBV-positive epithelial cancer models. Capsaicin significantly suppressed the expression of lytic genes, including BZLF1, BRLF1, BMRF1, and BLLF1, and reduced EBV virion production. Proteomic analysis revealed alterations in host cellular pathways associated with metabolism, chromatin organization, and cytoskeletal regulation, whereas metabolomic profiling demonstrated perturbations in nucleotide, amino acid, and polyamine metabolism processes involved in viral DNA replication and protein synthesis. Protein–protein interaction network analysis identified key host proteins, including HSP90AB1, MYH9, and ANXA2, implicated in metabolic reprogramming, cytoskeletal organization, and stress responses. Moreover, upstream regulators associated with EBV lytic activation, including p65, AP-1, HIF-1α, and SP1, were down-regulated following capsaicin treatment. Collectively, these findings demonstrate a multitarget inhibitory effect of capsaicin on EBV lytic reactivation and support its therapeutic potential against EBV-associated epithelial malignancies. Full article

Viruses cause a great number of infectious diseases with medical, veterinary, agricultural, social and economic impact. Their unique mechanisms to spread, overcome and resist the existing countermeasures require innovative and smart antiviral strategies such as the effective disinfection of enclosed environments with ensured broad-spectrum efficacy and minimized risks associated with handling liquid biocides. Formic acid (FA) is a well-established natural acaricide used in beehives with an antiviral potential; however, its application in a liquid form is hindered by severe corrosiveness and rapid, uncontrolled evaporation. This study describes a novel formulation of FA, using a cryogel carrier for achieving a vapor-phase inactivation of viruses, thus eliminating the need for direct contact between the disinfectant and the pathogen. Firstly, a poly(N-isopropylacrylamide) (PNIPAm) cryogel was synthesized by a procedure involving cryogenic treatment, photochemical crosslinking, and freeze-drying, and then the cryogel was swollen with 65% FA or _ddH₂O as a control. After an exposure of a panel of animal and human viruses to FA, evaporated by the polymer carrier for time intervals between 15 min and 12 h, they were neutralized completely as follows: Poliovirus (PV) as a surrogate for major bee viral pathogens for 60 min by 5.1 ∆lg; Feline calicivirus (FCV) for 60 min by 5.3 ∆lg; Adenovirus 5 (AdV5) for 12 h by 4.0 ∆lg; and Influenza virus A (IAV) for 15 min by 5.1 ∆lg. Results were recorded after titration, 48–72 h incubation, cytopathic effect estimation and NR uptake assay. Our results suggest that 65% FA, when delivered via the PNIPAm cryogel matrix, acts as a powerful agent for fumigation-like disinfection. This “dry” delivery strategy offers significant practical advantages: it eliminates the need for open liquid containers, prevents spill-related hazards, and provides an alternative for controlled, long-term release of active vapors. Full article

Hepatitis E virus (HEV) infection is generally self-limiting in immunocompetent individuals but may progress to chronic infection in immunocompromised patients, underscoring the need for effective antiviral therapies. Although ribavirin is currently used off-label for HEV treatment, its associated adverse effects highlight the need for safer alternatives. In this study, we screened an anti-viral compound library comprising 800 compounds using three HEV reporter systems designed to target distinct stages of the viral life cycle. Candidate compounds were further evaluated in PLC/PRF/5 cells using both acute and chronic infection models with wild-type genotype 3 HEV (HEV-3). Antiviral activity was assessed by measuring HEV RNA levels in culture supernatants. Elbasvir, a known inhibitor of hepatitis C virus (HCV) non-structural protein 5A (NS5A), was identified as the most potent candidate. Although multiple compounds showed inhibitory effects in reporter assays, only elbasvir achieved sustained suppression of HEV growth in long-term culture, reducing HEV RNA levels to below the limit of detection. In a chronic infection co-culture model, elbasvir maintained antiviral activity at non-cytotoxic concentrations. Time-of-addition analysis demonstrated that elbasvir inhibits an early step in the viral life cycle, specifically viral internalization. Furthermore, combination with ribavirin enhanced antiviral efficacy, resulting in sustained viral suppression without detectable cytotoxicity and exhibiting an additive interaction. Collectively, these findings identify elbasvir as a promising candidate for repurposing as an anti-HEV drug and support a combination strategy targeting distinct steps of the viral life cycle. Full article

Direct-acting antivirals (DAAs) have revolutionized hepatitis C virus (HCV) therapy, yet resistance-associated substitutions (RASs) remain a concern in specific clinical contexts. Here, we present a database-derived global overview of HCV RASs by analyzing 19,449 publicly available sequences across multiple genotypes and subtypes, encompassing both untreated and previously treated infections, in the NS3, NS5A, and NS5B genomic regions. We demonstrate a markedly heterogeneous distribution of RASs shaped by viral genotype, geographic origin, and treatment era. Importantly, RASs against pan-genotypic NS3 protease inhibitors (glecaprevir and voxilaprevir) were rare (generally <1% across genotypes). In contrast, NS5A inhibitors showed greater vulnerability, with the Y93H substitution detected at notable frequencies in major genotypes (3.2–7.0%) and near-universal resistance-associated substitutions (e.g., 100% Q30S) observed in the rare genotype 8. The NS5B nucleotide analogue sofosbuvir retained a high genetic barrier, with the canonical S282T substitution detected only sporadically (2.1% of genotype 4 sequences). At the population level, geographic heterogeneity was evident, with higher RAS frequencies observed in specific regions, alongside pronounced data gaps in high-prevalence areas of Africa. Temporal analyses revealed an increase in NS3 and NS5A RASs following the introduction of first-generation DAAs, with NS5A substitutions persisting into the current interferon-free era, whereas NS5B resistance remained consistently rare across all treatment periods. Together, these findings provide a global, population-level overview of resistance-associated HCV diversity and reinforce the durability of high-barrier regimens while highlighting persistent genotype-specific vulnerabilities with implications for antiviral resistance surveillance and HCV elimination efforts. Full article

Objective: To identify demographic, clinical, and behavioural determinants of COVID-19 vaccination and antiviral uptake in Australia using the Capability, Opportunity, Motivation-Behaviour (COM-B) framework with psychometric validation and LASSO-enhanced variable selection. Methods: Cross-sectional analysis of the 2024 KAB BREATHE survey (n = 5177) of Australian adults, intentionally enriched for risk-stacked (more than 1 chronic condition). Primary outcomes included 2023/2024 COVID-19 booster receipt, future vaccine intentions, vaccine/antiviral beliefs and antiviral uptake. Predictors included demographics, chronic conditions, and domain-specific leave-one-out (LOO) COM-B scores standardised to mean = 0, SD = 1. COM-B domains were assessed using Cronbach’s alpha. Univariate and multivariable logistic regression models were complemented by LASSO penalised logistic regression with 10-fold cross-validation. Results: Among 5177 Australian adults, the mean age was 51.5 years (SD 16.5), 61.4% (3179/5177) were female, and 70.3% (3638/5177) were classified as risk-stacked. Booster uptake declined sharply from 50.8% (2023) to 19.1% (2024). Cronbach’s alpha showed poor internal consistency for Capability (α = 0.006) and Opportunity (α = −0.383) but was acceptable for full Motivation (α = 0.78). In adjusted models, age (aOR 1.02–1.03 per year), medically associated risk factors (aOR 1.66–3.51), and tertiary education (aOR 1.34–1.79) consistently predicted higher uptake and intention. Renting (aOR 0.59–0.78) and current employment (likely inversely associated with age) (aOR 0.73–0.83) were associated with lower uptake across all vaccine outcomes. Adding LOO COM-B scores substantially improved model fit (e.g., 2024 booster AUC 0.73→0.83); Motivation per SD was the strongest predictor (aOR 2.44–4.94 for vaccine outcomes, 1.52–2.49 for antivirals). LASSO models achieved CV-AUCs of 0.78–0.87. Among COVID-positive respondents (n = 2576), only 15.2% received antiviral treatment. Conclusions: Age, clinical risk, and socioeconomic factors, particularly housing tenure and employment status, are key drivers of COVID-19 preventive behaviours (either positively or negatively). The COM-B framework, when corrected for circular prediction and validated via Cronbach’s alpha and LASSO, provides substantial explanatory value. Targeted interventions should address structural barriers faced by renters and younger, employed individuals while leveraging high motivation among older adults and clinically vulnerable groups. Implications for Public Health: These findings support a shift from knowledge-based campaigns towards equity-focused, multi-level public health strategies that address structural barriers to COVID-19 vaccination and antiviral access in Australia. Full article

During the pre-Omicron phases of the COVID-19 pandemic, patients with hematological neoplasms were characterized by very high morbidity and mortality rates. Remdesivir, a viral RNA-polymerase inhibitor, interferes with key SARS-CoV-2 enzymes, preventing the virus from multiplying. The use of convalescent plasma (CP) in treating patients with COVID-19 has been shown to be beneficial in patients with an impaired humoral response to infection, including most of those on active treatment for hematologic malignancies. This retrospective, non-interventional study was performed using the Croatian Cooperative Group for Hematological Diseases database of patients with hematological malignancies infected with SARS-CoV-2. Patients treated with remdesivir and/or CP were matched to those untreated according to age, disease type, and antineoplastic therapy. We identified 119 patients treated with remdesivir and/or CP fulfilling entry criteria and matched 116 according to our established criteria to one of the 374 untreated patients. Treatment significantly reduced COVID-19 mortality. The beneficial effect of antiviral therapy was limited to those who started antiviral treatment within 7 days of the onset of symptoms. Due to the exclusive enrolment of hematological patients with COVID-19, our study provides unique insights into the benefits of early application of both antiviral and CP therapy. It emphasizes the need for early administration before the infection has transformed into the hyperinflammatory phase. Full article

COVID-19 has spurred much interest in complementary and alternative agents for therapeutic purposes having antiviral and immunomodulatory effects. In these, natural products and bioactive compounds from plants have been at the center of attention due to their easy access, relatively low risk and long history of use in traditional medicine. This paper reviews in detail and critically assesses the scientific data that presently proposes the use of certain cannabinoids, cannabimimetic compounds and Artemisia species in the treatment and prevention of COVID-19. It gives an account of medicinal approaches to cannabinoids like cannabidiol (CBD), Δ9-tetrahydrocannabinol (THC) alongside other minor cannabinoids and synthetic and naturally-occurring cannabimimetics. The paper reports the potential of Artemisia annua and other species as treatments, especially focusing on their antiviral, anti-regulatory, anti-inflammatory and immunomodulating properties. It highlights the molecular interactions with SARS-CoV-2 targets as well as cytokine regulation and modulation of oxidative stress pathways, with special emphasis on these areas. The paper raises multiple issues like preclinical and clinical studies, safety aspects, regulatory hurdles and drawbacks related to the use of these natural compounds. After analyzing all the available data, the article entertains the idea of a cannabinoid–Artemisia combination as a supportive or adjunct therapy in COVID-19 treatment. It also points out that the clinical trials are insufficient concerning the establishment of effectiveness, determination of the appropriate dosage and assurance of the long-term safety of the treatment. Full article

Background: Diagnostic anchoring to a presumed infectious etiology may delay recognition of underlying genetic disorders in children with neurodevelopmental impairment. Case presentation: A case of a child with sensorineural hearing loss, visual impairment, and developmental delay is reported; cytomegalovirus (CMV) infection was identified at 6 months of age based on positive serology and detection of viral DNA in serum and urine. Given the timing of testing, congenital CMV infection (cCMV) could not be definitively confirmed. Antiviral therapy with valganciclovir was administered. Despite antiviral treatment, severe neurodevelopmental impairment and hearing loss persisted, associated with facial dysmorphism, bilateral cryptorchidism, pectus excavatum, and optic nerve hypoplasia, findings not fully attributable to CMV infection. Brain magnetic resonance imaging (MRI) showed nonspecific findings. Chromosomal microarray analysis (CMA) performed at 4.5 years of age identified a heterozygous 908 kb de novo microdeletion at 19p13.2p13.13 containing NFIX (MIM *164005) and other morbid genes. The de novo variant was confirmed by parental testing, and the unifying genetic diagnosis of NFIX-related Malan syndrome (MIM#614753) was established. Conclusions: This case emphasizes the importance of reconsidering the initial diagnosis when the clinical phenotype is not fully consistent with an infectious etiology. Early genomic testing, including CMA, may facilitate timely recognition of underlying genetic syndromes in children with complex neurodevelopmental presentations. Full article

Zika virus (ZIKV) infection during pregnancy is a critical driver of Congenital Zika Syndrome (CZS), yet the mechanisms of pathogenesis at the placental barrier remain incompletely understood. This article is a translational, observational, and experimental study combining clinical placental analyses, placental explants cultures and in vivo murine model to investigate the mechanisms involved in ZIKV infection. We evaluate the histopathological analyses to verify presence of inflammation in ZIKV-infected human placentas from newborns with CZS and without CZS (N-CZS), identifying more intense Hofbauer cell hyperplasia, villitis and decidual inflammation in CZS group. Moreover, placental immunohistochemistry analyses identified decreased TLR4 expression in the villi and reduced TNF and IL-10 levels across placental layers of CZS group. Next, we investigated the effects of inflammation on viral replication and explored whether the flavonoid Naringenin (NGN) could modulate this inflammation. Using a placental villous explant model, we verified that inflammation induced by LPS exacerbates viral replication and pathological markers. Notably, treatment with the NGN rescued the inflammatory and virological outcomes. These findings were further validated in a murine model of congenital infection, where NGN administration alleviated microcephaly-related structural alterations in ZIKV-exposed neonates. Our results indicate that placental inflammation is a key provocateur of ZIKV replication and subsequent fetal brain malformation. Furthermore, we identify NGN as a promising bifunctional antiviral and anti-inflammatory candidate for mitigating the developmental impacts of ZIKV infection. Full article

The ADP-glucose pyrophosphorylase (AGPase) gene family plays an essential role in starch metabolism and stress adaptation. However, its function in antiviral defense remains largely uncharacterized. Cucumber (Cucumis sativus L.), a globally important vegetable crop, frequently experiences severe yield losses due to viral infections. In this study, we systematically identified five AGPase genes in cucumber, categorizing them into large and small subunits. Analysis of conserved motifs revealed ten conserved sequences, with the NTP (Nucleoside Triphosphate) transferase domain representing a signature feature of the AGPase family. Promoter regions contained multiple cis-regulatory elements associated with stress responses and hormone signaling. Transcriptomic profiling revealed tissue-specific expression patterns of CsAGP genes, with pronounced enrichment in leaves. Notably, CsAGP2, CsAGP4, and CsAGP5 were strongly induced under biotic and abiotic stresses. Of these, CsAGP4 exhibited rapid, transient induction specifically in the virus-resistant line ‘228’, but not in the susceptible line ‘65G’. Hormonal treatments showed that abscisic acid (ABA) rapidly activated most CsAGP genes and acted synergistically with viral infection to amplify CsAGP4 expression. Functional analysis via CRISPR/Cas9-mediated knockout of CsAGP4 revealed that the mutation disrupted starch granule formation and significantly altered resistance to watermelon mosaic virus (WMV) in ‘Poinsett 97’. Our work provides a systematic characterization of the AGPase gene family in cucumber and establishes its role in defense responses. Importantly, we identify CsAGP4 as a positive regulator of antiviral immunity, highlighting its potential as a target for breeding virus-resistant cucumber varieties. Full article

Background Cytomegalovirus (CMV) infection is a major contributor to morbidity and mortality in recipients of hematopoietic stem cell transplant (HSCT), solid organ transplant (SOT), and chimeric antigen receptor T-cell (CAR-T) therapy. While antiviral agents remain the cornerstone of treatment, CMV-specific immunoglobulins (CMVIG) have been utilized as adjunct therapy with variable outcomes. This study aims to evaluate the virological response and tolerability of CMVIG in cases of severe or refractory CMV viremia, with or without CMV disease. Methods: We conducted a single-center retrospective case series of adult recipients of SOT, allogeneic HSCT, and/or CAR-T cell therapy who developed CMV viremia or disease and received at least one dose of CMVIG between May 2017 and May 2023 at our center. Virological improvement within 14 days of starting CMVIG and tolerability of CMVIG are the primary outcome of this study. Results: A total of 33 patients were included. Of these, 29 underwent transplantation [SOT: 48.2%, HSCT: 51.7%], and five underwent CAR-T cell therapy (one post-HSCT). High-risk CMV serostatus was present in 12%. CMV viremia was documented in 32 patients (97%), and tissue-invasive disease was present in 11 patients (33.3%). Virological response, was observed in 65.6% of the cohort. The median time to undetectable CMV viral load following CMVIG initiation was 28 days. CMVIG was well-tolerated. All-cause mortality at 90 days remained high (57%). Conclusion: In this case series, CMVIG demonstrated a virological response rate of 65.6% in patients with severe or refractory CMV infection. While CMVIG was well-tolerated with minimal adverse events, the high mortality rate despite virological response suggests that CMVIG may be insufficient for this critically ill population. Our findings should be interpreted as observational data from a small case series, and prospective controlled trials are needed to establish the true benefit of CMVIG in combination with standard antiviral therapy. Full article

Marine algal polysaccharides have been widely investigated as antiviral candidates, yet nearly all anti-dengue studies have focused on sulfated species. Whether algal polysaccharides lacking prominent sulfation can inhibit dengue virus (DENV) remains unexplored. Here, we profiled the stage-specific antiviral activity of a heteropolysaccharide (GLHP) from Gracilaria lemaneiformis, whose Fourier-transform infrared (FT-IR) spectrum lacks characteristic sulfate ester absorption bands, against DENV serotype 2 (DENV-2) in Huh7 and BHK-21 cells. GLHP exhibited low cytotoxicity (CC₅₀ exceeding 1000 μg/mL in Huh7 cells and approximately 950 μg/mL in BHK-21 cells). Time-of-addition analysis revealed that co-inoculation GLHP treatment (Co-inoc.) produced the strongest and most consistent inhibition of intracellular viral RNA, whereas pre-inoculation GLHP treatment (Pre-inoc.) was ineffective, indicating that the antiviral activity is predominantly associated with the virus–cell contact and entry stage. GLHP additionally reduced extracellular progeny virus output under post-inoculation GLHP treatment (Post-inoc.) conditions, and this reduction exceeded the corresponding change in intracellular viral RNA levels, suggesting an additional effect that may involve either a late replication step or secondary entry blockade of progeny virions. Attenuation of virus-induced cytopathic effects under Co-inoc. conditions further supported the antiviral activity. To our knowledge, these findings identify GLHP as the first non-sulfated marine polysaccharide shown to exhibit stage-defined antiviral activity against DENV-2 and support further investigation of its antiviral potential and structural determinants. Full article

Background/Objectives: Bleomycin is an antineoplastic antibiotic used in the management of various malignancies. Nevertheless, its benefits are constrained by the development of pulmonary fibrosis. Amentoflavone, a biflavonoid, exhibits diverse pharmacological activities, including anti-inflammatory, antiviral, antioxidant, and antitumor effects, whereas alogliptin possesses antioxidant and anti-inflammatory properties. This study aimed to assess the potential protective effects of alogliptin and/or amentoflavone in a murine model of bleomycin-induced pulmonary fibrosis and to clarify the underlying mechanisms. Methods: Fifty male C57BL/6 mice were randomly divided into 5 equal groups: control, bleomycin, bleomycin + alogliptin, bleomycin + amentoflavone, and bleomycin + alogliptin + amentoflavone. The assessed endpoints included lung weight/body weight index, lung tissue fibrotic mediators, oxidative stress parameters, proinflammatory cytokines, and pyroptotic and autophagy mediators. Also, the bronchoalveolar lavage fluid (BALF) was evaluated for total and differential leukocytic counts and lactate dehydrogenase (LDH) activity. Moreover, vascular responses to potassium chloride, phenylephrine, and carbachol, together with tracheal responses to carbachol were determined. Lung tissues were further examined histopathologically and immunohistochemically. Results: Treatment with alogliptin and/or amentoflavone significantly decreased the lung weight/body weight index and BALF LDH activity, concomitant with mitigation of lung tissue oxidative stress parameters, fibrotic mediators, apoptosis, and pyroptosis with a significant augmentation of autophagy signals, alongside marked improvement in the lung architecture and vascular and airway reactivity compared with the bleomycin group. These effects were most pronounced with animals treated with the alogliptin/amentoflavone combination. Conclusions: These findings suggest that combined alogliptin and amentoflavone may constitute a promising strategy to prevent bleomycin-induced lung fibrosis. Full article

Background: Hepatitis C virus (HCV) remains a major cause of preventable liver-related mortality in the United States despite highly effective direct-acting antivirals (DAAs). Contemporary assessment of mortality trends and disparities is essential for elimination efforts. Methods: Using CDC WONDER multiple cause-of-death data (1999–2023), we identified HCV-related deaths using ICD-10 codes for acute and chronic HCV (B17.1, B18.2) and calculated age-adjusted mortality rates (AAMRs) per 100,000 (2000 US standard). Rates were stratified by sex, race/ethnicity, census region, and 2013 NCHS urban–rural classification. Joinpoint regression quantified temporal inflection points and annual percent changes (APCs). Results: Overall HCV-related AAMR increased from 1.8 (1999) to a peak of 5.0 (2014), then declined to 2.3 (2023), with a marked post-2014 decrease (APC −8.2%). Mortality was consistently higher in males than females (2023 rate ratio 2.57). In 2023, American Indian/Alaska Native individuals had the highest mortality (AAMR 8.7; rate ratio 3.48 vs. non-Hispanic White), followed by non-Hispanic Black individuals (AAMR 6.2; rate ratio 2.48). Mortality remained highest in the West and was higher in non-metropolitan than metropolitan counties (AAMR 2.8 vs. 2.3; rate ratio 1.22), with a slower post-2014 decline in non-metropolitan areas. Conclusions: Our findings indicate that while the DAA era has been associated with a substantial reduction in HCV-related mortality at the national level, this progress has not been uniform across all populations. Persistent excess mortality among Native American and non-Hispanic Black individuals may reflect inequities in the HCV care cascade, including screening, confirmatory testing, linkage to specialty care, insurance-related restrictions, and the high cost of antiviral therapy. These results highlight the need for policies and public health strategies that improve equitable and affordable access to curative HCV treatment. Full article

Chlorine dioxide (ClO₂) is a neutral oxidant molecule with a short lifespan once in contact with electron donors (organic matter). ClO₂ solutions have antiviral, antibacterial, antifungal, anti-protozoan, anti-inflammatory, anticancer, and wound-healing activity and it was used at safe concentrations on patients from different countries during the COVID-19 pandemic. In Mexico, 1067 COVID-19 patients received compassionate treatments with ClO₂ during the 2020/2021 pandemic years. We describe the treatments and clinical reports of these patients, as it concerns the oxygen saturation (SpO₂) recovery, and provide a biochemical explanation. The number of healed patients was 1057, >99% of the total and SpO₂ showed a hyperbolic fast increase. This might happen because ClO₂ attracts one electron from the organic matter and produces a chlorite anion (${\mathrm{ClO}}_2^{-}$). This new molecule is known to exhibit metabolic activity in the blood stream. On the one hand, it will perform the aforementioned antibiotic and healing properties. On the other hand, it will also allow the production of oxygen (O₂) to be transported by the Oxyhemoglobin. This reaction is mediated by an intermediate state of a ferryl molecule (Fe=O) in the allosteric heme site of methemoglobin, which behaves as a reductase enzyme. This reaction can explain the rapid and steady increase in O₂ saturation in healed patients. Full article