Search Results (1,021)

Endophytic fungi are promising sources of novel antiviral compounds, and the crude extract from Alternaria alternata PO4PR2 has previously shown anti-HIV-1 activity. This study evaluated its efficacy against integrase strand-transfer inhibitor (INSTI)-resistant HIV-1 and its mechanism of action. Key resistance mutations (Y143H, G118R, N155H, and R263K) were introduced into the HIV-1 pNL4.3 clone via site-directed mutagenesis and confirmed through Sanger sequencing. Viral infectivity was assessed in TZM-bl cells, while cytotoxicity was measured using an MTT assay. Antiviral activity was determined through a luciferase-based assay, and integration inhibition was evaluated using integrase activity assays and Alu-gag nested PCR. The extract demonstrated potent inhibition of resistant mutants, with low IC₅₀ values (0.02971–0.1652 μg/mL), and showed minimal cytotoxicity (CC₅₀ = 300 μg/mL), maintaining over 80% cell viability. It inhibited integrase activity by 67%, specifically targeting the strand-transfer step, and significantly reduced integrated viral DNA. Molecular docking of 14 compounds identified coumarin derivatives as key bioactive metabolites, exhibiting mutation-tolerant binding within the integrase catalytic pocket. Overall, these findings highlight PO4PR2 as a promising source of compounds for developing new therapies targeting drug-resistant HIV-1 integrase. Full article

Background: Advanced cirrhosis induces profound CD4⁺ T-cell depletion through splenic sequestration and immune dysregulation. Pneumocystis jirovecii pneumonia risk thresholds remain undefined in non-HIV immunocompromised populations, necessitating investigation in cirrhotic patients. Objectives: To investigate the potential association between peripheral CD4⁺ T-cell counts and opportunistic infections (OI)—specifically Pneumocystis jirovecii (PJ)—in hospitalized patients with liver disease, and to characterize clinical outcomes across immunological risk strata. Methods: We retrospectively analyzed 455 adults hospitalized in a single institution with hepatic disorders. CD4⁺ T-cell counts were available in 227/455 patients. Among these, 22 patients met predefined immunological risk criteria (CD4⁺ < 500/µL and/or HIV positivity) and were classified into three immunological risk clusters (IRCs): IRC-A (HIV−, CD4⁺ < 200/µL; n = 9), IRC-B (HIV+, CD4⁺ < 200/µL; n = 7), and IRC-C (HIV−, CD4⁺ 200–499/µL; n = 6). PJ PCR testing was evaluated when available. Results: Among 455 patients, in-hospital mortality was 103/455 (22.6%). Of the 22 immunologically at risk patients, 15/22 had cirrhosis. PJ PCR was performed in 8/22 patients (IRC-A: 2; IRC-B: 4; IRC-C: 2), with 3/8 positive (37.5%): IRC-A (1/2), IRC-B (1/4), IRC-C (1/2). Ct values ranged from 27.0 to 31.7. Two PJ-PCR–positive cirrhotic patients (IRC-A: n = 1; IRC-C: n = 1) survived without specific anti-PJ therapy; one HIV-positive patient (IRC-B) received trimethoprim-sulfamethoxazole and survived. In-hospital mortality was 5/9 (55.6%) in IRC-A, 2/7 (28.6%) in IRC-B, and 3/6 (50.0%) in IRC-C; none of the deaths were attributable to PJ pneumonia. Conclusions: Severe CD4⁺ T-cell depletion (<200/µL) was common among cirrhotic patients and associated with PJ detection (3/8 tested), but not with PJ-related mortality (0/3). Mortality was primarily driven by hepatic decompensation and bacterial infections. CD4⁺ assessment may improve risk stratification in cirrhosis; however, prospective, multicenter studies are warranted to validate these findings and to evaluate CD4-guided strategies for the prevention of opportunistic infections. Full article

This study aimed to explore and describe the barriers to Antiretroviral Therapy (ART) adherence among children in Ekurhuleni, Gauteng. A quantitative, cross-sectional design using a survey method was employed. Convenience sampling was used to recruit 157 parents, guardians, and caregivers (PGCs) who consented to participate in the study. Data was collected using self-report questionnaires and analysed using descriptive statistics and frequency distributions. The study was not designed or statistically powered to formally test associations between variables; therefore, only descriptive statistical analyses were conducted. The reliability and validity of the instrument were ensured, and ethical clearance was obtained from the relevant authorities prior to data collection. The study was conducted in accordance with established ethical principles and in compliance with the Declaration of Helsinki. The findings revealed that there were multiple barriers to children’s adherence to ART. Approximately one-third of PGCs reported being fully informed about the importance of ART adherence, while the majority indicated being only partially informed. Missed doses emerged as a significant challenge, with a substantial proportion reporting missed medication on one or more days, and only 31.2% administering ART consistently on time. Difficulties in understanding blood test results were also reported. In addition, a notable proportion of PGCs admitted to missing clinic appointments. These findings emphasize the need for strengthened caregiver education, ongoing support, and tailored interventions directed at primary health care nurses to promote consistent ART adherence among children. Full article

HIV-1 protease (PR) is an essential enzyme in the viral life cycle and a primary target of antiretroviral therapies, particularly protease inhibitors (PIs). Understanding the dynamics of viral evolution and the factors governing the emergence or loss of resistance-associated mutations is critical for improving PI efficacy and managing drug resistance in HIV/AIDS treatment. In this study, we investigated the impact of three natural HIV-1 polymorphisms (T12A, L63Q, and H69N), whose prevalence varies depending on treatment status and viral subtype, on the structural stability and conformational dynamics of PR using molecular dynamics (MD) simulations. Three independent 500 ns MD simulations were performed for the native protease and each mutant system. Although none of the mutations disrupts the overall structural integrity of HIV-1 PR, they induce mutation-specific alterations in flexibility and residue interactions. In particular, T12A and H69N exhibit increased structural deviations, especially in the flap regions, along with enhanced conformational fluctuations. In contrast, the L63Q mutation shows a slight reduction in flap flexibility compared to both the native protease and the other mutants. Consistently, the fraction of time spent in open-flap conformations is higher for T12A and H69N and lower for L63Q relative to the native system. Moreover, mutations in the Fulcrum (T12A) and Cantilever (L63Q and H69N) regions do not disrupt the long-range network of correlated motions observed in the native protease, both inter- and intra-monomer, but instead increase the extent of correlated and anti-correlated motions in other regions of PR. Full article

Background/Objectives: In several contexts, Dried Sample Spot Devices (DSSDs) offer a convenient and safe alternative for sampling, storage, and shipment, allowing the transport and storage of biological samples at room temperature, reducing shipment costs and improving access to diagnostics in faraway sites. This can be pivotal for the use of the therapeutic drug monitoring of anti-HIV treatment: therefore, this study aimed to develop and validate a UHPLC–MS/MS method for the simultaneous quantification of 12 antiretroviral drugs, including the recently introduced long-acting agents, in Dry Plasma Spots (DPSs). Methods: First, 100 µL of plasma sample and 100 µL of internal standard solution were spotted on each DSSD. After complete drying, DPSs were added with an acidifying solution (ammonium acetate buffer pH 4), and then, each sample underwent extraction with hexane-dichloromethane 50:50 (v/v). After tumbling, the organic phase was evaporated and reconstituted for injection. An Acquity UPLC HSS T3 1.8 µm, 2.1 × 150 mm column at 50 °C enabled separation, performed using H₂O + F.A. 0.05% (phase A) and ACN + F.A. 0.05% (phase B) as the mobile phase in gradient elution mode, for a total run time of 15 min. Results: The method was validated over the clinically relevant concentration ranges. For all quality control levels, accuracies ranged from 98.2% to 114.1%, and intra-day and inter-day RSD values ranged from 2.7% to 9.7% and 5.2% to 13.9%, respectively. All analytes demonstrated satisfactory short- and long-term stability in DPSs, confirming the suitability of shipment and storage at room temperature. Conclusions: The method demonstrated robustness and reproducibility in accordance with FDA and EMA guidelines. It ensures satisfactory accuracy and rapid analysis, supporting its application in clinical practice, including for monitoring the newest long-acting drugs. Full article

Background: Hepatitis B virus (HBV) infection continues to be a major public health concern, especially in sub-Saharan Africa, where widespread epidemics and restricted availability of long-term antiviral therapies result in higher mortality and morbidity rates. Drug repurposing represents a strategic approach to accelerate the discovery of effective therapies by leveraging agents with demonstrated antiviral and immunomodulatory activity. Product Nkabinde (PN) is a patented African polyherbal formulation initially developed for the treatment of HIV. Recent experimental studies demonstrate PN’s potent anti-HIV activity and significant immunomodulatory effects in human immune cells, implicating host-directed mechanisms relevant to chronic viral infections. This study combines an integrative application of network pharmacology and molecular docking to evaluate the repurposing potential of PN as a multi-target agent in HBV. Method: Bioactive components of PN were screened, and compound-associated targets were intersected with HBV-associated genes (proteins) to construct a protein–protein interaction (PPI) network. Topological analysis identified 10 hub targets (STAT1, STAT3, SRC, HCK, EGFR, SYK, PIK3CA, PIK3CB, PIK3R1, and PTPN11). Gene Ontology and KEGG pathway enrichment were performed with an FDR cut-off < 0.05. Significantly enriched pathways included JAK–STAT signaling, chemokine signaling, EGFR-TKI resistance, PI3K complex signaling, and viral infection pathways, particularly those related to Kaposi sarcoma virus and HSV-1, indicating immunoregulatory and antiviral roles. Molecular docking was performed using AutoDock Vina 1.1.2 to evaluate binding affinity and interaction mode of key PN phytochemicals against the hub proteins, and results were compared to their respective co-crystallized ligands. Results: Molecular docking indicated that major phytochemicals from PN exhibited significant binding affinities across all 10 hub host targets, typically outperforming or closely matching their respective co-crystallized ligands. The strongest contacts were observed for β-sitosterol–PIK3CB (−14.2 kcal/mol) and oleanolic acid–SYK (−14.0 kcal/mol), which were significantly stronger than the co-crystallized ligands (−7.9 and −8.3 kcal/mol, respectively), indicating robust stabilization within catalytic and regulatory pockets. Procyanidin B2 toward HCK (−10.5 vs. −7.9 kcal/mol) and PIK3CA (−9.5 vs. −7.3 kcal/mol), quercetin toward PIK3R1 (−10.6 vs. −8.2 kcal/mol) and PTPN11 (−9.2 vs. −7.5 kcal/mol), rutin toward SRC (−10.5 vs. 7.8 kcal/mol), and diosgenin toward EGFR (−9.4 vs. 8.4 kcal/mol). Procyanidin B2 maintained robust multi-hydrogen bonding networks, demonstrating significant binding, despite STAT1 and STAT3 docking showing identical affinities to co-crystals. Conserved hydrogen bonds, π–cation interactions, and significant hydrophobic packing at ATP-binding clefts and regulatory domains supported these interaction patterns, indicating competitive suppression of host signaling nodes taken over by HBV. Conclusions: Together, these results demonstrate that the components of PN possess strong multitarget binding capabilities across the PI3K/AKT, JAK–STAT, SRC-family kinase, EGFR, and SYK pathways, supporting their potential repurposing as host-directed HBV therapeutics with the ability to impede immune evasion, viral persistence, and HBV-associated oncogenic progression. Full article

Background: Pre-eclampsia (PE) is a significant cause of maternal and perinatal morbidity and mortality globally and is characterized by impaired endothelial function and disturbances in coagulation pathways. The effects of Human Immunodeficiency Virus (HIV) on the immune and coagulation systems have been investigated during pregnancy, but there are few reports on anticoagulant factors in pregnant women who are infected with HIV and develop PE. This investigation compares plasma protein C levels in pregnant women with pre-eclampsia and those without pre-eclampsia, and compares the results based on their HIV status. Methods: A hospital-based cross-sectional study design was used for the current research, which was carried out at Charlotte Maxeke Johannesburg Academic Hospital, South Africa. A total of 83 pregnant women participated in the study and were categorized into one of four groups: normotensive HIV-negative (n = 36); normotensive HIV-positive (n = 18); pre-eclamptic HIV-negative (n = 21); and pre-eclamptic HIV-positive (n = 8). Data collected included demographic information and clinical characteristics that were abstracted from maternity records. Plasma protein C concentrations were determined by ELISA (enzyme-linked immunosorbent assay). Nonparametric statistical methods were used to compare the mean values of plasma protein C between each of the four groups, and significance was set at p < 0.05. Subgroup analyses, particularly for the pre-eclamptic HIV-positive group (n = 8), were considered exploratory due to small sample sizes. Results: As would be anticipated, both systolic and diastolic blood pressure values were significantly elevated in the pre-eclamptic group when compared to the normotensive control subjects (p < 0.0001). There were no statistically significant differences in plasma protein C concentration between the normotensive and pre-eclamptic groups, nor between the HIV-negative and HIV-positive groups. Similarly, there were no significant differences in plasma protein C concentration when comparing all four study groups (Kruskal–Wallis test p = 0.2295). Conclusions: Plasma protein C concentrations did not vary significantly according to the presence of pre-eclampsia or HIV status in this cohort. These findings suggest that protein C concentrations were not measurably altered between groups within this study population. However, due to the small sample size in key subgroups, these findings should be considered preliminary and interpreted with caution. Larger, adequately powered studies are required to further investigate potential associations between HIV infection, pre-eclampsia, and anticoagulant pathways during pregnancy. Full article

Toxoplasmosis is a cosmopolitan zoonosis that particularly threatens pregnant women, their fetuses and immunocompromised individuals. Among people living with HIV, Toxoplasma gondii may invade the central nervous system, producing neuropathological effects associated with mental and psychiatric disorders. We assessed the seroprevalence of anti-T. gondii IgG in HIV-infected and HIV-uninfected residents of Iquitos, Peru, and evaluated an in-house ELISA based on total lysate antigen (TLA) and recombinant GRA1 (rGRA1), with ELISA-TLA compared against a commercial kit. In this observational cross-sectional study, 151 participants were enrolled: 92 HIV-positive and 59 HIV-negative. ELISA-TLA showed a seroprevalence of 88.08% (133/151), reaching 91.30% (84/92) in the HIV-positive group and 83.05% (49/59) in the HIV-negative group. ELISA-rGRA1 showed a similar epidemiological pattern but lower overall seroprevalence, 81.46% (123/151), with 84.78% (78/92) in HIV-positive and 74.58% (44/59) in HIV-negative participants. Taken together, both TLA and rGRA1-based ELISAs showed similar epidemiological patterns, supporting the consistency of the serological findings. These results also indicate very high exposure to T. gondii in Iquitos, particularly among HIV-positive individuals, in whom prior exposure is clinically relevant because of the risk of reactivation under immunosuppression. Serological screening and preventive counseling may therefore be warranted in high-burden Amazonian communities. Full article

Background: RNA therapeutics represent a rapidly advancing field with significant potential for treating viral infections and cancer. This review examines the current landscape of RNA-based strategies, including siRNA, miRNA mimics, and antisense oligonucleotides. For viral infections, the focus is on hepatitis B (HBV) and C (HCV), HIV, and SARS-CoV-2. Approaches include targeting viral transcripts directly (e.g., siRNAs against HBV surface antigen) or host factors critical for viral replication (e.g., anti-miR-122 miravirsen for HCV). The successful development of mRNA vaccines for COVID-19 is highlighted as a major breakthrough, demonstrating the feasibility of rapid RNA vaccine deployment. The manuscript reviews several RNA therapeutics in oncology that have reached clinical trials. These include TargomiR (a miR-16 mimic for mesothelioma), cobomarsen (an anti-miR-155 for lymphomas), and MRX34 (a miR-34a mimic for various solid tumours). The review also covers emerging candidates like an miR-221 inhibitor and various strategies for breast cancer, such as targeting Bcl-2, KRAS, and specific miRNAs. A critical challenge across both fields is developing efficient and safe delivery systems, including lipid nanoparticles, GalNAc conjugates, and bacterial minicells. Despite promising preclinical results, clinical translation has been hampered by issues like insufficient delivery efficiency to human tumours, toxicity, and the complex, interconnected regulatory networks of miRNAs, which can lead to unpredictable off-target effects. Conclusions: While RNA therapeutics hold immense promise, overcoming delivery barriers and enhancing understanding of RNA regulatory networks are essential for future success. Full article

The discovery of novel anti-infective agents is a continuous challenge in medicinal chemistry, particularly due to the rise in resistant fungal and viral strains. Within this context, the biphenyl subunit has been identified as a highly versatile privileged structure capable of interacting with diverse protein targets via hydrophobic and π-interactions. The purpose of this study is to review the pharmacological potential of biphenyl-based compounds, focusing on their application as anti-infective agents. We comprehensively analyzed recent literature and rational design strategies concerning biphenyl derivatives, examining structure-activity relationships, molecular docking insights, and structural optimizations aimed at enhancing both pharmacodynamics and pharmacokinetics. The reviewed studies demonstrate that incorporating biphenyl moieties yields compounds with potent antifungal and antiviral activities. Specifically, optimized biphenyl derivatives exhibit strong inhibitory effects against resistant Candida strains and crucial viral targets, including mutant variants of the HIV-1 reverse transcriptase and protease enzymes. Furthermore, strategic modifications, such as scaffold hopping and the introduction of specific substituents, successfully mitigated cytotoxicity and improved metabolic stability against cytochrome P450 enzymes. Biphenyl serves as a robust and adaptable scaffold for drug design. Its rational structural optimization provides a viable pathway to overcome drug resistance and develop effective, metabolically stable anti-infective therapeutics. Full article

Mycobacterium tuberculosis (Mtb) remains a significant public health threat, responsible for 1.6 million deaths in 2021. The development of new treatments is particularly urgent for immunocompromised individuals, including those with Mtb/HIV coinfection, who experience severe disease outcomes. Previous studies demonstrated that blockade of VEGFR1, a receptor expressed on monocytes that mediates their recruitment to infection sites, limits Mtb-induced pathology in immunocompetent mice of both Mtb-resistant (C57BL/6J) and Mtb-susceptible (B6.C3H-sst1) strains. The present study extends these findings by evaluating the VEGFR1/2 blockade strategy in immunocompromised hosts. Treatment with the VEGFR1/2 blocker SU5416 (semaxanib) reduced monocyte infiltration into the lungs of Mtb-infected immunocompromised RAG1KO mice without affecting bacterial protection. Reduced monocyte recruitment improved lung pathology. VEGFR1/2 blockade also decreased the number of NK cells in the lungs of RAG1KO mice. Notably, an elevated ratio and increased absolute number of neutrophil granulocytes were observed in the Mtb-infected lungs of both immunocompetent and immunocompromised mice following SU5416 administration. However, this increase in neutrophils did not exacerbate lung pathology, as most recruited granulocytes remained within the lung vasculature. The beneficial effect of VEGFR1/2 blockade in RAG1KO animals suggests that further investigation of VEGFR blockers, such as SU5416, as adjunctive therapy to anti-tuberculosis drug regimens for immunocompromised populations with tuberculosis is warranted. Full article

Lasiosphaera calvatia (LC), referring to the dry fruiting bodies of certain puffball fungi, has been extensively used in traditional Chinese medicine (TCM). Documented in the Mingyi Bielu, its traditional medicinal properties encompass clearing heat, detoxification, reducing swelling, and stopping bleeding. Modern applications include promoting wound healing, anti-cancer therapy, lowering blood sugar, relieving coughs, and combating HIV, among others. This comprehensive review explores the evolving scientific understanding of LC, covering its botany, traditional use, phytochemistry, pharmacology, toxicology, and quality control. A wide range of chemical components, including steroids, phenolics, volatile compounds, amino acids, polysaccharides, and polypeptides, have been isolated and identified using diverse analytical techniques. Among these, sterols (particularly ergosterol derivatives), polysaccharides, and polypeptides are considered the major bioactive constituents. The active ingredients of LC are associated with relatively few side effects, a characteristic that supports its use in pediatric populations and underscores its significant research potential. These findings validate the traditional uses of LC and lay the groundwork for further scientific exploration. The sources utilized in this study encompass Web of Science, PubMed, CNKI site, the Chinese Pharmacopoeia, and doctoral and master’s theses. Full article

Antitubercular drug-induced liver injury (ATDILI) poses a significant obstacle to successful tuberculosis treatment, including for tuberculous lymphadenitis. Its global incidence varies considerably, typically ranging from 2% to 30%, influenced by factors like patient demographics, co-morbidities, and geographical context. Despite some findings suggesting potentially lower rates in tuberculous lymphadenitis, the inherent hepatotoxic nature of standard anti-TB drugs means the risk remains clinically relevant. Key risk factors for ATDILI encompass older age, female gender, pre-existing liver conditions, HIV co-infection, malnutrition, alcoholism, and genetic polymorphisms, particularly in N-acetyltransferase 2 which affects isoniazid metabolism. The mechanisms of injury are drug-specific: isoniazid primarily causes hepatocellular damage via oxidative stress from toxic metabolites, while rifampicin induces cholestasis and endoplasmic reticulum stress, and pyrazinamide is linked to mitochondrial dysfunction. Management involves prompt withdrawal of antitubercular therapy when liver enzyme thresholds are exceeded, followed by careful reintroduction. Challenges are amplified in resource-limited settings due to higher prevalence of risk factors and limited access to consistent monitoring and sophisticated diagnostics. Promising advancements include safer regimens like the 3-month once-weekly isoniazid-rifapentine (3HP) for latent TB, which significantly reduces hepatotoxicity. The development of shorter active TB regimens and novel anti-TB drugs with improved safety profiles further aims to enhance treatment adherence and reduce ATDILI incidence, ultimately improving patient outcomes globally. Full article

Background/Objectives: Chronic hepatitis B (HBV) and C (HCV) remain major public health challenges in Romania despite vaccination and antiviral therapy. Understanding infection patterns in different healthcare settings is essential for targeted elimination strategies. Methods: We conducted the prospective screening phase of the RE-LINK project (January–June 2025) through two nationwide private laboratory networks. Adults undergoing routine testing were screened for HBsAg and anti-HCV. HBsAg-positive samples were further analyzed for HBV DNA, HBeAg, anti-HBe, anti-HDV, and HDV RNA, while anti-HCV-positive cases were tested for HCV RNA. Risk factors were assessed using chi-square and logistic regression analyses. Results: Among 9149 individuals (66.6% women with a median age of 53 years), HBsAg prevalence was 2.9%, and anti-HCV was 1.3%, both increasing significantly with age (p < 0.001). Of all HBsAg-positive individuals, 12.5% had undetectable HBV DNA, 70.4% had low viremia (<2000 IU/mL), and 17.1% had high viral loads. Anti-HDV antibodies were detected in 2.3% of HBsAg-positive subjects, all with detectable HDV RNA (range 1250–680,000 IU/mL). Significant risk factors for HBsAg positivity were male sex, older age, urban residence, physician-indicated testing, neuropsychiatric comorbidity, family or parental hepatitis, and institutional/orphanage care, while HBV vaccination and moderate alcohol use were protective. Anti-HCV positivity correlated with older age, cardiovascular disease, elevated transaminases, transfusions, surgery, and HIV co-infection. Only 20.2% of anti-HCV-positive individuals were viremic. Conclusions: Private-laboratory screening reveals residual low-replicative HBV and declining viremic HCV, while community programs uncover HDV and advanced disease in vulnerable groups. A coordinated approach integrating private, community, and hospital-based pathways can accelerate elimination efforts and ensure that HDV is not overlooked. Full article

The Superposing Significant Interaction Rules (SSIR) method is briefly revisited. The original version of the algorithm consists of dealing with rules that evaluate the individual presence or absence of substituents in the molecular structures of a combinatorial chemical family. Here, an extension is developed, allowing for the systematic consideration of multilevel conditions, i.e., the presence or absence of not only single residues but also groups of residues attached to a particular substitution site. This possibility expands the universe of possible definable rules. Then, the original SSIR version becomes a particular case of the framework presented in this manuscript. A numerical example involving a family of anti-HIV compounds is provided to illustrate the application and potential of the extended method. Procedures for generating predictions for new in silico virtual molecular structures are also shown. Full article