Search Results (7,808)

Chronic infection with the hepatitis B virus (HBV) results in over 1 million deaths annually. Although currently licensed treatments, including pegylated interferon-α and nucleoside/nucleotide analogs, can inhibit viral replication, they rarely eradicate covalently closed circular DNA (cccDNA) reservoirs. Moreover, vaccination does not offer therapeutic benefit to already infected individuals or non-responders. Consequently, chronic infection is maintained by the persistence of cccDNA in infected hepatocytes. For this reason, novel therapeutic strategies that permanently inactivate cccDNA are a priority. Obligate heterodimeric transcription activator-like effector nucleases (TALENs) provide the precise gene-editing needed to disable cccDNA. To develop this strategy using a therapeutically relevant approach, TALEN-encoding mRNA targeting viral core and surface genes was synthesized using in vitro transcription with co-transcriptional capping. TALENs reduced hepatitis B surface antigen (HBsAg) by 80% in a liver-derived mammalian cell culture model of infection. In a stringent HBV transgenic murine model, a single dose of hepatotropic lipid nanoparticle-encapsulated TALEN mRNA lowered HBsAg by 63% and reduced viral particle equivalents by more than 99%, without evidence of toxicity. A surveyor assay demonstrated mean in vivo HBV DNA mutation rates of approximately 16% and 15% for Core and Surface TALENs, respectively. This study presents the first evidence of the therapeutic potential of TALEN-encoding mRNA to inactivate HBV replication permanently. Full article

Background/Objectives: Hemodialysis catheter-related bloodstream infection (HD-CRBSIs) is a main cause of morbidity in hemodialysis. New preventive strategies have emerged, such as using lock solutions with antiseptic or antibiotic capacity. In this study, the antimicrobial effect was analyzed in vitro and with a catheter model of lock solutions of gentamicin (LSG), gentamicin/heparin (LSG/H), and gentamicin/citrate (LSG/C) in clinical and ATCC strains of Pseudomonas aeruginosa and Staphylococcus aureus. Methods: The formation, minimum inhibitory concentration, and minimum inhibitory concentration of the biofilm and minimum biofilm eradication concentration of the lock solutions were determined. Additionally, colony-forming unit assays were performed to evaluate the antimicrobial efficacy of the lock solutions in a hemodialysis catheter inoculation model. Results: The minimum inhibitory concentration (MIC) of planktonic cells of both P. aeruginosa and S. aureus for LSG/H and LSG/C was 4 µg/mL. In the minimum biofilm inhibitory concentration (MBIC) tests, the LSG/H was less effective than LSG/C, requiring higher concentrations for inhibition, contrary to the minimum biofilm eradication concentration (MBEC), where LSG/H was more effective. All lock solutions eradicated P. aeruginosa biofilms in the HD catheter model under standard conditions. Nevertheless, under modified conditions, the lock solutions were not as effective versus ATCC and clinical strains of S. aureus. Conclusions: Our analysis shows that the lock solutions studied managed to eradicate intraluminal mature P. aeruginosa in non-tunneled HD catheters under standard conditions. Biofilm inhibition and eradication were observed at low gentamicin concentrations, which could optimize the gentamicin concentration in lock solutions used in HD catheters. Full article

Background/Objective: Staphylococcus aureus (S. aureus) is a clinically significant pathogenic bacterium. Daptomycin (DAP) is a cyclic lipopeptide antibiotic used to treat infections caused by multidrug-resistant Gram-positive bacteria, including S. aureus. However, DAP currently faces clinical limitations due to its short half-life, toxic side effects, and increasingly severe drug resistance issues. This study aimed to develop a biomimetic nano-drug delivery system to enhance targeting ability, prolong blood circulation, and mitigate resistance of DAP. Methods: DAP-loaded chitosan nanocomposite particles (DAP-CS) were prepared by electrostatic self-assembly. Macrophage membrane vesicles (MM) were prepared by fusion of M1-type macrophage membranes with 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC). A biomimetic nano-drug delivery system (DAP-CS@MM) was constructed by the coextrusion process of DAP-CS and MM. Key physicochemical parameters, including particle diameter, zeta potential, encapsulation efficiency, and membrane protein retention, were systematically characterized. In vitro immune escape studies and in vivo zebrafish infection models were employed to assess the ability of immune escape and antibacterial performance, respectively. Results: The particle size of DAP-CS@MM was 110.9 ± 13.72 nm, with zeta potential +11.90 ± 1.90 mV, and encapsulation efficiency 70.43 ± 1.29%. DAP-CS@MM retained macrophage membrane proteins, including functional TLR2 receptors. In vitro immune escape assays, DAP-CS@MM demonstrated significantly enhanced immune escape compared with DAP-CS (p < 0.05). In the zebrafish infection model, DAP-CS@MM showed superior antibacterial efficacy over both DAP and DAP-CS (p < 0.05). Conclusions: The DAP-CS@MM biomimetic nano-drug delivery system exhibits excellent immune evasion and antibacterial performance, offering a novel strategy to overcome the clinical limitations of DAP. Full article

Cholangiocarcinoma (CCA) is highly prevalent in the Greater Mekong sub-region, especially northeastern Thailand, where infection with the liver fluke Opisthorchis viverrini is a major etiological factor. Limited therapeutic options and the absence of reliable early diagnosis tools impede effective disease control. Atractylodes lancea (Thunb.) DC.—long used in Thai and East Asian medicine, contains atractylodin (ATD), a potent bioactive compound with anticancer potential. Here, we developed ATD-loaded poly(lactic co-glycolic acid) nanoparticles (ATD PLGA NPs) and evaluated their antitumor efficacy against CCA. The formulated nanoparticles had a mean diameter of 229.8 nm, an encapsulation efficiency of 83%, and exhibited biphasic, sustained release, reaching a cumulative release of 92% within seven days. In vitro, ATD-PLGA NPs selectively reduced the viability of CL-6 and HuCCT-1 CCA cell lines, with selectivity indices (SI) of 3.53 and 2.61, respectively, outperforming free ATD and 5-fluorouracil (5-FU). They suppressed CL-6 cell migration and invasion by up to 90% within 12 h and induced apoptosis in 83% of cells through caspase-3/7 activation. Micronucleus assays showed lower mutagenic potential than the positive control. In vivo, ATD-PLGA NPs dose-dependently inhibited tumor growth and prolonged survival in CCA-xenografted nude mice; the high-dose regimen matched or exceeded the efficacy of 5-FU. Gene expression analysis revealed significant downregulation of pro-tumorigenic factors (VEGF, MMP-9, TGF-β, TNF-α, COX-2, PGE₂, and IL-6) and upregulation of the anti-inflammatory cytokine IL-10. Collectively, these results indicate that ATD-PLGA NPs are a promising nanotherapeutic platform for targeted CCA treatment, offering improved anticancer potency, selectivity, and safety compared to conventional therapies. Full article

Canine visceral leishmaniasis (CVL) is a major zoonosis that poses a growing challenge to public health services, as successful disease management requires sensitive, specific, and rapid diagnostic methods capable of identifying infected animals even at a subclinical level. The objective of this study was to evaluate the performance of the recombinant chimeric protein rMELEISH3 as an antigen in ELISA assays for the robust diagnosis of CVL. The protein was expressed in a bacterial system, purified by affinity chromatography, and evaluated through a series of serological assays using serum samples from dogs infected with Leishmania infantum. ROC curve analysis revealed a diagnostic sensitivity of 96.4%, a specificity of 100%, and an area under the curve of 0.996, indicating excellent discriminatory power. Furthermore, rMELEISH3 was recognized by antibodies present in the serum of dogs with low parasite loads, reinforcing the diagnostic potential of the assay in asymptomatic cases. It is concluded that the use of the recombinant antigen rMELEISH3 could significantly contribute to the improvement of CVL surveillance and control programs in endemic areas of Brazil and other countries, by offering a safe, reproducible and effective alternative to the methods currently recommended for the serological diagnosis of the disease. Full article

Background/Objectives: Mycobacterium abscessus is an opportunistic pathogen causing infections mainly in patients with immunosuppression and chronic pulmonary pathologies. Extended treatment periods are needed to tackle this pathogen, bacterial eradication is rare, and recurrence can take place with time. New alternative treatments are being investigated, such as bacteriophage therapy. This work describes the characterization of the mycobacteriophage P3MA, showing its ability to infect clinical and standard M. abscessus strains. Methods: Phylogenetic analysis, electron microscopy, growth curves, biofilm assays, checkerboard, and granuloma-like medium studies were performed. Results: P3MA inhibited the growth of clinical samples in both planktonic and biofilm states as well as in a granuloma-like model. The study of the interaction with antibiotics revealed that P3MA exhibited an antagonistic effect combined with clarithromycin, indifference with amikacin, and synergy with imipenem. Conclusions: All these results suggest that, after genetic engineering, P3MA could be a promising candidate for phage therapy in combination with imipenem, including lung infections. Full article

Background/Objectives: The rapid emergence of multidrug-resistant bacterial infections demands innovative non-antibiotic therapeutic strategies. Dual-modal photoresponse therapy integrating photodynamic (PDT) and photothermal (PTT) effects offers a promising rapid antibacterial approach, yet designing single-material systems with synergistic enhancement remains challenging. This study aims to develop uniform Cu-based metal–organic framework micrometer cubes (Cu-BN) for efficient PDT/PTT synergy. Methods: Cu-BN cubes were synthesized via a one-step hydrothermal method using Cu(NO₃)₂ and 2-amino-p-benzoic acid. The material’s dual-mode responsiveness to visible light (420 nm) and near-infrared light (808 nm) was characterized through UV–Vis spectroscopy, photothermal profiling, and reactive oxygen species (ROS) generation assays. Antibacterial efficacy against multidrug-resistant Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was quantified via colony counting under dual-light irradiation. Results: Under synergistic 420 + 808 nm irradiation for 15 min, Cu-BN (200 μg/mL) achieved rapid eradication of multidrug-resistant E. coli (99.94%) and S. aureus (99.83%). The material reached 58.6 °C under dual-light exposure, significantly exceeding single-light performance. Photodynamic analysis confirmed a 78.7% singlet oxygen (¹O₂) conversion rate. This enhancement stems from PTT-induced membrane permeabilization accelerating ROS diffusion, while PDT-generated ROS sensitized bacteria to thermal damage. Conclusions: This integrated design enables spatiotemporal PDT/PTT synergy within a single Cu-BN system, establishing a new paradigm for rapid-acting, broad-spectrum non-antibiotic antimicrobials. The work provides critical insights for developing light-responsive biomaterials against drug-resistant infections. Full article

Wheat (Triticum aestivum L.) is a crucial global food crop. The intensive crop farming, monoculture cultivation, and impact of climate change affect the susceptibility of wheat cultivars to biotic stresses, mainly caused by soil fungal pathogens, especially those belonging to the genus Fusarium. This situation threatens yield and grain quality through root and crown rot. While conventional chemical fungicides face resistance issues and environmental concerns, biological alternatives like seed priming with natural metabolites are gaining attention. Polyamines, including putrescine, spermidine, and spermine, are attractive priming agents influencing plant development and abiotic stress responses. Spermine in particular shows potential for in vitro antifungal activity against Fusarium. Optimising spermine concentration for seed priming is crucial to maximising protection against Fusarium infection while ensuring robust plant growth. In this research, we explored the potential of the polyamine spermine as a seed treatment to enhance wheat resilience, aiming to identify a sustainable alternative to synthetic fungicides. Our findings revealed that a six-hour seed soak in spermine solutions ranging from 0.5 to 5 mM did not delay germination or seedling growth. In fact, the 5 mM concentration significantly stimulated root weight and length. In complementary in vitro assays, we evaluated the antifungal activity of spermine (0.5–5 mM) against three Fusarium species. The results demonstrated complete inhibition of Fusarium culmorum growth at 5 mM spermine. A less significant effect on Fusarium graminearum and little to no impact on Fusarium oxysporum were found. The performed analysis revealed that the spermine had a fungistatic effect against the pathogen, retarding the mycelium growth of F. culmorum inoculated on the seed surface. A pot experiment with Bulgarian soft wheat cv. Sadovo-1 was carried out to estimate the effect of seed priming with spermine against infection with isolates of pathogenic fungus F. culmorum on plant growth and disease severity. Our results demonstrated that spermine resulted in a reduced distribution of F. culmorum and improved plant performance, as evidenced by the higher fresh weight and height of plants pre-treated with spermine. This research describes the efficacy of spermine seed priming as a novel strategy for managing Fusarium root and crown rot in wheat. Full article

Background: Coronavirus disease 2019 (COVID-19) has led to the expansion of the spectrum of invasive fungal infections beyond traditional immunocompromised populations. Although COVID-19-associated pulmonary aspergillosis is increasingly being recognised, COVID-19-associated mucormycosis remains rare, particularly in non-endemic regions. Concurrent COVID-19-associated invasive tracheobronchial aspergillosis and pulmonary mucormycosis with histopathological confirmation is exceedingly uncommon and poses significant diagnostic and therapeutic challenges. Case presentation: We report the case of a 57-year-old female with myelodysplastic syndrome who underwent haploidentical allogeneic haematopoietic stem cell transplantation. During post-transplant recovery, she developed COVID-19 pneumonia, complicated by respiratory deterioration and radiological findings, including a reverse halo sign. Bronchoscopy revealed multiple whitish plaques in the right main bronchus. Despite negative serum and bronchoalveolar lavage fluid galactomannan assay results, cytopathological examination revealed septate hyphae and Aspergillus fumigatus was subsequently identified. Given the patient’s risk factors and clinical features, liposomal amphotericin B therapy was initiated. Subsequent surgical resection and histopathological analysis confirmed the presence of Rhizopus microsporus. Following antifungal therapy and surgical intervention, the patient recovered and was discharged in stable condition. Conclusions: This case highlights the critical need for heightened clinical suspicion of combined invasive fungal infections in severely immunocompromised patients with COVID-19, even in non-endemic regions for mucormycosis. Early tissue-based diagnostic interventions and prompt initiation of optimal antifungal therapy are essential for obtaining ideal outcomes when co-infection is suspected. Full article

The increasing prevalence of antibiotic resistance and the limited availability of antiviral therapeutics for pathogens such as human respiratory syncytial virus (hRSV) underscore the need for novel, plant-derived antimicrobial substances. In this study, we evaluated the antiproliferative, antibacterial, and antiviral activities of aqueous leaf extracts from two plants commonly found in North America, Osage orange (M. pomifera) and spearmint (M. spicata). Both extracts exhibited no significant cytotoxic or morphologic impact on HEp-2 human cancer cells up to 25 mg/mL. However, both extracts demonstrated strong dose-dependent antibacterial activity, significantly inhibiting replication of E. coli and S. aureus at concentrations ≥ 1 mg/mL. Antiviral assays revealed that both extracts inhibited hRSV infectivity, with spearmint extract showing higher potency (EC₅₀ = 1.01 mg/mL) compared to Osage orange (EC₅₀ = 3.85 mg/mL). Gas chromatography–mass spectrometry (GC-MS) identified three major extract constituents: 3-hydroxybenzyl alcohol, 4-hydroxybenzyl alcohol (Osage orange), and R-(-)-carvone (spearmint). Among these, only carvone significantly inhibited hRSV in vitro, suggesting its key role in spearmint’s antiviral activity. These findings highlight the therapeutic potential of Osage orange and spearmint leaf extracts, particularly as sources of water-soluble compounds with antimicrobial properties, and support further investigation into their mechanisms of action and broader clinical relevance. Full article

Background/Objectives: The diminished efficacy of azoles in treating fungal infections is attributed to the emergence of resistance among pathogenic fungi. Employing a synergistic approach with other compounds to enhance the antifungal activity of azoles has shown promise, yet the availability of clinically valuable adjuvants for azoles and allylamines remains limited. Studies have demonstrated that the human host environment provides multiple carbon sources, which can influence the susceptibility of C. albicans to antifungal agents. Therefore, a comprehensive investigation into the mechanisms by which carbon sources modulate the susceptibility of C. albicans to azoles may uncover a novel pathway for enhancing the antifungal efficacy of azoles. Methods: This study explored the impact of various carbon sources on the antifungal efficacy of azoles through methodologies including minimum inhibitory concentration (MIC) assessments, super-MIC growth (SMG) assays, disk diffusion tests, and spot assays. Additionally, the mechanism by which galactose augments the antifungal activity of azoles was investigated using a range of experimental approaches, such as gene knockout and overexpression techniques, quantitative real-time PCR (qRT-PCR), Western blot analysis, and cycloheximide (CHX) chase experiments. Results: This study observed that galactose enhances the efficacy of azoles against C. albicans by inhibiting the translation of Erg1. This results in the suppression of Erg1 protein levels and subsequent inhibition of ergosterol biosynthesis in C. albicans. Conclusions: In C. albicans, the translation of Erg1 is inhibited when galactose is utilized as a carbon source instead of glucose. This novel discovery of galactose’s inhibitory effect on Erg1 translation is expected to enhance the antifungal efficacy of azoles. Full article

Conessine is a steroidal alkaloid found in many plants. The pharmacological efficacies of conessine on various ailments, including antiviral effects against Zika, Herpes, and Coronavirus, were reported. However, the effect of conessine on the influenza virus was still unknown. In this study, conessine exhibited a strong inhibitory effect against influenza A virus (IAV) infection. We examined the effect of conessine on IAV using green fluorescent protein (GFP)-expressing Influenza A/PR8/34 and wild-type A/PR8/34. The fluorescence-activated cell sorting, fluorescence microscopy, cytopathic effect analysis, and plaque assay demonstrated that conessine significantly inhibits IAV infection. Consistently, immunofluorescence results showed that conessine strongly reduces the expression of IAV proteins. The time-of-drug-addition assay revealed that conessine could affect the viral attachment and entry into the cells upon IAV infection. Further, conessine eradicated the virus before binding to the cells in the early stage of viral infection. Our results suggest that conessine has strong anti-viral efficacy against IAV infection and could be developed as an anti-influenza viral agent. Full article

Porcine reproductive and respiratory syndrome virus (PRRSV), an enveloped single-stranded positive-sense RNA virus, poses a significant threat to global swine production. Despite the availability of modified live virus and inactivated vaccines, their limited efficacy and safety concerns highlight the urgent need for novel antiviral therapeutics. This study aimed to investigate the molecular mechanisms by which lycopene inhibits PRRSV replication. Initial assessments confirmed that lycopene did not adversely affect cellular viability, cell cycle progression, or apoptosis. Using fluorescence microscopy, flow cytometry, immunoblotting, quantitative real-time PCR (qRT-PCR), and viral titration assays, lycopene was shown to exhibit potent antiviral activity against PRRSV. Mechanistic studies revealed that lycopene suppresses reactive oxygen species (ROS) production, which is critical for PRRSV proliferation. Additionally, lycopene attenuated PRRSV-induced inflammatory responses, as demonstrated by immunoblotting, ELISA, and qRT-PCR assays. These findings suggest that lycopene inhibits PRRSV replication by modulating ROS levels and mitigating inflammation, offering a promising avenue for the development of antiviral therapeutics. This study provides new insights and strategies for combating PRRSV infections, emphasizing the potential of lycopene as a safe and effective antiviral agent. Full article

The problem of spreading harmful infections through contaminated surfaces has become more acute during the recent coronavirus pandemic. The design of self-cleaning materials, which can continuously decompose biological contaminants, is an urgent task for environmental protection and human health care. In this study, the surface of blended cotton/polyester fabric was functionalized with N-doped TiO₂ (TiO₂-N) nanoparticles using titanium(IV) isopropoxide as a binder to form durable photoactive coating and additionally decorated with Cu species to promote its self-cleaning properties. The photocatalytic ability of the material with photoactive coating was investigated in oxidation of acetone vapor, degradation of deoxyribonucleic acid (DNA) fragments of various lengths, and inactivation of PA136 bacteriophage virus and Candida albicans fungi under visible light and ultraviolet A (UVA) radiation. The kinetic aspects of inactivation and degradation processes were studied using the methods of infrared (IR) spectroscopy, polymerase chain reaction (PCR), double-layer plaque assay, and ten-fold dilution. The results of experiments showed that the textile fabric modified with TiO₂-N photocatalyst exhibited photoinduced self-cleaning properties and provided efficient degradation of all studied contaminants under exposure to both UVA and visible light. Additional modification of the material with Cu species substantially improved its self-cleaning properties, even in the absence of light. Full article

Honey bees are essential pollinators for the ecosystem and food crops. However, their health and survival face threats from both biotic and abiotic stresses. Fungi, microsporidia, and bacteria might significantly contribute to colony losses. Therefore, rapid and sensitive diagnostic tools are crucial for effective disease management. In this study, molecular assays were developed to quickly and efficiently detect the main honey bee pathogens: Nosema ceranae, Aspergillus flavus, Paenibacillus larvae, and Black queen cell virus. In this context, new primer pairs were designed for use in quantitative Real-time PCR (qPCR) reactions. Various protocols for extracting total nucleic acids from bee tissues were tested, indicating a CTAB-based protocol as the most efficient and cost-effective. Furthermore, excluding the head of the bee from the extraction, better results were obtained in terms of quantity and purity of extracted nucleic acids. These assays showed high specificity and sensitivity, detecting up to 250 fg of N. ceranae, 25 fg of P. larvae, and 2.5 pg of A. flavus DNA, and 5 pg of BQCV cDNA, without interference from bee DNA. These qPCR assays allowed pathogen detection within 3 h and at early stages of infection, supporting timely and efficient management interventions. Full article