Research into the profiles of serial killers has largely relied on generalisations derived from studies conducted in the United States and parts of Europe, limiting the applicability of such findings to culturally diverse contexts. The present study addresses this gap by examining the profiles of serial killers in India, the most populous country in the world. Adopting an exploratory descriptive research design, the study analyses 132 serial killers reported between 1997 and 2025 using a database constructed from both primary and secondary sources. Employing quantitative methods, the study examines key variables including spatial analysis, socio-economic characteristics, prior criminal history, and victim counts. The findings of the study largely aligned with existing literature while also identifying certain patterns that are unique to the Indian context. Characteristics of Indian Serial Killers from 1997 to 2025Most research on serial killers is based in the United States and Europe. As a result, there is less knowledge about the applicability of findings from these studies to non-Western countries. This study fills this gap by analysing the characteristics of 132 serial killers in India from 1997 to 2025. By using interviews, police records, prison files, and media reports, the study explains the social and economic backgrounds of serial killers, their prior criminal records, and the number of victims they have had. Many of the findings were similar to Western research, but the study also identified some features that are unique to Indian serial killers.
"Overkill" is a specific homicidal pattern marked by the excessive and disproportionate use of violence beyond what is necessary to cause death to the extent that a high number of post-mortem lesions are often found on the corpse. Though it constitutes a minority of homicide cases, overkill is increasingly observed in domestic and familial contexts, where symbolic or psychopathological motivations often emerge. This study presents a review of literature concerning overkill in familial context and a five-year retrospective analysis (2021-2025) of judicial cases managed by the Institute of Legal Medicine of Messina, identifying eight incidents that met overkill criteria based on the offenders' modus operandi. All cases occurred in domestic settings and involved eleven victims (seven females, four males), with injuries primarily affecting the head, neck, and thorax. In all cases, both active and passive defense wounds were present. One case featured postmortem injuries and attempted concealment through carbonization. A multidisciplinary forensic approach was employed-integrating crime scene reconstruction, bloodstain pattern analysis, PMCT, autopsy, histology, toxicology, and forensic engineering. This comprehensive methodology enabled accurate reconstructions of the homicidal dynamics and offered decisive elements in understanding the severity and operational modalities of the aggression. The findings revealed consistent anatomical patterns and weapon typologies, echoing those reported in existing literature, while also underlining the recurrent presence of psychiatric comorbidities in offenders. This study highlights the importance of adopting a structured, interdisciplinary investigative framework for overkill cases. Beyond aiding case resolution, such a framework contributes to a deeper medico-legal understanding of escalating domestic violence, thus offering potential predictive and preventive value in future forensic and public health contexts.
Complete genome sequences were determined for three uncharacterized betabaculoviruses (Baculoviridae: Lefavirales) from noctuid moth species. These viruses included Eudryas unio granulovirus 1112 (EuunGV-1112), Eudryas unio granulovirus 1229 (EuunGV-1229), and Autographa gamma granulovirus Darmstadt (AugaGV-Darmstadt). Analysis of the features and open reading frame (ORF) contents of the genome sequences indicated that all three viruses were closely related to Helicoverpa armigera granulovirus (HearGV; Betabaculovirus helarmigerae) and Xestia c-nigrum granulovirus (XecnGV; Betabaculovirus xecnigri), two betabaculoviruses that kill larvae slowly and appear to suppress alphabaculovirus replication in coinfections. Phylogenetic inference with whole genome or core gene alignments grouped the EuunGV isolates in a clade with XecnGV. This clade was contained within a larger clade with AugaGV. Pairwise nucleotide distance estimation confirmed that AugaGV and the EuunGV isolates are viruses of Betabaculovirus xecnigri. Five ORFs were found to be unique to the EuunGV/AugaGV/HearGV/XecnGV group of betabaculoviruses, though what role the products of these ORFs play in the unusual features of their pathology remains to be determined. PCR analysis of cadavers from bioassays of AugaGV and EuunGV indicated that these viruses are able to infect and replicate in larvae of Helicoverpa zea and Spodoptera frugiperda, species which are susceptible to HearGV.
Efficiently eradicating superbacteria without harming normal cells and inducing bacterial drug-resistance holds significant importance in safeguarding human health. Herein, we discovered a novel selective bactericidal material synthesized from natural cellulose as the backbone, with cationic groups introduced via a deoxygenation process. Compared to conventional ester-type cationic cellulose derivatives (CCDs), deoxy-type CCDs exhibit high selective bactericidal activity. Through tailored cationic structure and substitution degree modulation, these derivatives achieve targeted bacterial eradication at low concentrations while maintaining mammalian cell biocompatibility. Specifically, deoxy-type CCDs, C-Ts-BenA0.80 and C-Ts-TBuP0.83, demonstrate minimum inhibitory concentrations (MICs) of 16 μg/mL and 4 μg/mL against E. coli and S. aureus, respectively, with corresponding selectivity indices of 312 and 50. Deoxy-type CCDs have strong cell-membrane depolarization ability owing to the unique surface charge distribution, thus leading to bacterial death. Based on the physical membrane-disruption mechanism, deoxy-type CCDs do not induce the emergence of drug-resistant bacteria and can effectively kill a variety of superbugs, including ESKAPE bacteria. The synergistic effect between the linkage bond and cations offers a new approach for constructing highly efficient and nontoxic inactivating materials.
This paper provides a rigorous mathematical resolution of the open global stability problem for a "shock-and-kill" model of HIV-1/SIV infection in brain reservoirs recently formulated by Roda et al. (2021). The model explicitly incorporates the effects of latency-reversing agents and enhanced immune clearance of reactivated cells. We derive an explicit formula for the basic reproduction number R 0 , which serves as the sole threshold parameter governing viral eradication versus persistence and integrates infection pathways from both productive and latent compartments. By combining the next-generation matrix approach with an extended graph-theoretic Lyapunov method for multigraphs with parallel arcs, we rigorously establish that the disease-free equilibrium is globally asymptotically stable when R 0 ≤ 1 , whereas a unique productive equilibrium exists and is globally asymptotically stable when R 0 > 1 . To resolve the sign-indefinite quadratic perturbations induced by structurally distinct parallel transmission arcs-a fundamental bottleneck of classical graph-theoretic Lyapunov schemes-we develop a refined composite Lyapunov framework equipped with hierarchically calibrated parameters. Systematic asymptotic scaling and multi-parameter tuning eliminate indefinite cyclic quadratic interactions, securing strict negative definiteness of the Lyapunov derivative and overcoming key limitations of conventional graph-based methods. These global stability results provide a definitive mathematical answer to whether therapeutic interventions guarantee viral eradication or lead to persistent brain-reservoir infection. Furthermore, they furnish a rigorous theoretical foundation for the "shock-and-kill" strategy and establish mathematically precise conditions to guide the design of safe, effective interventions for eliminating HIV-1/SIV from CNS reservoirs.
Ixodes scapularis is a consequential tick species in North America that can transmit multiple pathogens of canine and public health significance. Acaricidal speed is critical for reducing the risk of pathogen transmission. Herein, the immediate and sustained acaricidal speed of three monthly oral endectocide products against I. scapularis are compared. Thirty-two dogs were randomly allocated equally among four groups and treated on day 0 with an endectocide containing lotilaner (Credelio Quattro™), afoxolaner (NexGard® PLUS) or sarolaner (Simparica Trio™), or left untreated. On days -2, 21, and 28, dogs were infested with 50 laboratory-reared, adult I. scapularis. Live tick counts were performed at 4, 8, 12, 24, and 48-h post-treatment, and after each reinfestation. Efficacy was compared using a linear mixed model of geometric mean live tick counts. At 8-h post-treatment of an existing infestation, only the lotilaner group had significantly lower mean live tick counts than the untreated group. At each subsequent assessment through 48 h, all treated groups had significantly lower mean live tick counts than the untreated group. Compared to the untreated group, following the day 21 reinfestation, mean live tick counts were significantly lower in the lotilaner group at 4 through 48 h, in the sarolaner group at 4, 24, and 48 h, and in the afoxolaner group at 24 and 48 h. Compared to the untreated group, following the day 28 reinfestation, mean live tick counts were significantly lower in the lotilaner group at 8 through 48 h, in the sarolaner group at 12 through 48 h and, in the afoxolaner group at 24 and 48 h. Within group, between day 0 and day 28, significant slowing of acaricidal speed was observed for sarolaner at the 12-h timepoint and for afoxolaner at the 8, 12, and 24-h timepoints. No significant loss of acaricidal speed occurred for lotilaner between day 0 and day 28. In dogs, lotilaner has a faster onset of acaricidal activity against I. scapularis than sarolaner or afoxolaner. Lotilaner's acaricidal speed is sustained throughout the monthly dosing interval, whereas sarolaner and afoxolaner show slower acaricidal activity at the end of the month than at the beginning.
Effective plaque control is essential for preventing caries and periodontal diseases. While curcumin-mediated photodynamic therapy has demonstrated antimicrobial efficacy, its clinical use is limited by poor solubility and bioavailability. This study evaluates a curcumin-loaded liposomal photodynamic gel for enhanced in vitro plaque control. Curcumin was encapsulated in phosphatidylcholine-based liposomes and incorporated into a bioadhesive gel. Physicochemical properties, including particle size, zeta potential, and encapsulation efficiency, were characterized. Singlet oxygen (1O2) generation was measured under blue light (450 nm) using the 1,3-diphenylisobenzofuran assay. A multispecies oral biofilm model was established with Streptococcus mutans, Lactobacillus casei, Actinomyces viscosus, and Fusobacterium nucleatum. Biofilms were treated with curcumin gel ± light, and bacterial viability was quantified. The liposomal gel exhibited a mean particle size of ~ 250 nm, encapsulation efficiency of ~ 85%, and pH of ~ 6.8. Curcumin liposomal gel generated a higher 1O2 yield than free curcumin. Photodynamic treatment reduced viable biofilm bacteria by > 4 log10 CFU/ml, significantly more than control treatments. Curcumin liposomal gel shows enhanced 1O2 production and potent photodynamic biofilm inactivation. This formulation may offer a novel adjunct for nonantibiotic plaque control. Résumé Contexte:Un contrôle efficace de la plaque dentaire est essentiel pour prévenir les caries et les maladies parodontales. Bien que la thérapie photodynamique médiée par la curcumine ait démontré une efficacité antimicrobienne, son utilisation clinique reste limitée par sa faible solubilité et sa biodisponibilité réduite. Cette étude évalue un gel photodynamique liposomal chargé en curcumine pour améliorer le contrôle de la plaque dentaire in vitro.Matériels et méthodes:La curcumine a été encapsulée dans des liposomes à base de phosphatidylcholine, puis incorporée dans un gel bioadhésif. Les propriétés physicochimiques, notamment la taille des particules, le potentiel zêta et l’efficacité d’encapsulation, ont été caractérisées. La production d’oxygène singulet (^1O2) sous lumière bleue à 450 nm a été mesurée à l’aide du test au 1,3-diphénylisobenzofurane. Un modèle de biofilm oral multispecies a été établi avec Streptococcus mutans, Lactobacillus casei, Actinomyces viscosus et Fusobacterium nucleatum. Les biofilms ont été traités avec le gel de curcumine avec ou sans exposition lumineuse, puis la viabilité bactérienne a été quantifiée.Résultats:Le gel liposomal présentait une taille moyenne des particules d’environ 250 nm, une efficacité d’encapsulation d’environ 85 % et un pH d’environ 6,8. Le gel liposomal de curcumine a généré une production de ^1O2 plus élevée que la curcumine libre. Le traitement photodynamique a réduit la viabilité bactérienne du biofilm de plus de 4 log10 UFC/ml, de manière significativement supérieure aux traitements témoins.Conclusion:Le gel liposomal de curcumine montre une production accrue d’oxygène singulet (^1O2) et une puissante inactivation photodynamique du biofilm. Cette formulation pourrait constituer un nouvel adjuvant non antibiotique pour le contrôle de la plaque dentaire.
CD8+ T cell-mediated cytotoxicity classically occurs through engagement of an alpha-beta T cell receptor (TCRαβ) with a peptide-class I major histocompatibility complex (pMHC). However, it is also known that cytotoxic CD8+ T lymphocytes (CTLs) can kill tumor cells in a pMHC-independent manner. The relative physiologic contribution and biological significance of pMHC-independent CTL killing remain unclear, and a receptor shared between CTLs and natural killer (NK) cells is generally invoked as the mechanism by which this occurs. In this study, we used acute myeloid leukemia (AML) as a model to examine mechanisms of pMHC-independent cytotoxicity and found a paradoxical TCR-dependent, MHC-independent mechanism that requires CD64. Utilizing knockouts of potential AML ligands and CTL receptors, we demonstrate that pMHC-independent cytotoxicity is a potent mechanism of CTL-mediating killing of AML cells and is largely restricted to CD64-expressing cells through an IFNγ-regulated process. Notably, we found that pMHC-independent CTL killing is not due to activation of commonly implicated NK activating receptors but rather requires an activated TCRαβ/CD3 complex. Thus, we identify a CD64-dependent, pMHC-independent, TCR-dependent mode of CTL cytotoxicity that appears highly enriched for in AML.
Natural killer (NK) cells are innate lymphocytes that play a critical role in protective immunity against diverse intracellular pathogens and cancers. Their primary function is to kill target cells that are infected, malignantly transformed, or coated by antibodies via antibody-dependent cellular cytotoxicity (ADCC). NK cells can also be genetically engineered to express chimeric antigen receptors (CARs) that enable targeted recognition of specific antigens. Quantitative measurement of NK-cell cytotoxicity is essential for assessing baseline functionality and for preclinical evaluation of monoclonal antibodies and CAR-engineering strategies. However, in vitro functional assays remain highly variable across laboratories due to differences in cell preparation, target cells, effector-to-target ratios, co-incubation times, and readout methods, limiting reproducibility and cross-study comparisons. This article presents a standardized protocol for quantitative assessment of NK-cell cytotoxicity using flow cytometry and real-time, live-cell imaging. Primary human NK cells and CAR-expressing NK-92 cells were evaluated for their ability to kill cancer cells and antibody-coated target cells in a 96-well plate format to measure natural cytotoxicity, CAR-mediated killing, and ADCC. Target-cell survival was measured either continuously using live-cell imaging or at a defined time point by flow cytometry, which also enabled phenotypic characterization of NK cells and target cells. These protocols provide a robust framework using routine tissue culture, imaging, and flow cytometry methods to enable reproducible quantification of NK-cell effector functions for studies of innate immunity and NK cell-based immunotherapies.
The first-in-class diarylquinoline (DARQ) bedaquiline (BDQ) is in the medicines list for drug-resistant tuberculosis. TBAJ-587 is a next-generation DARQ with improved anti-Mycobacterium tuberculosis (Mtb) activity and reduced cardiac repolarization abnormalities. The in vitro efficacy of TBAJ-587 and its main metabolites (M2, M3 and M12) was analyzed under standard (ST) growth conditions and with cholesterol (CHO), or fatty acids (FA) as physiologically relevant alternative carbon sources. Minimal inhibitory concentration (MIC) assays and time-kill assays (TKA) linked to drug measurements in bacterial samples were performed to allow correlation of pharmacodynamics (PD) with actual in vitro pharmacokinetics (PK). The most active compounds, TBAJ-587 and its M3 metabolite, exhibited broth media and concentration dependent efficacy showing a bactericidal effect at ≥5x MIC. Bacterial cultures treated with 1x MIC and 2x MIC of TBAJ-587 resumed growth after 28 days and displayed moderate increased MIC values compared to untreated conditions, which were linked to new variants of BDQ resistance mutations in the atpE, atpB, and Rv0678 genes. This study revealed that TBAJ-587 and its metabolites bind to polystyrene plastic-ware, the most commonly used material in antimicrobial research, being the effective unbound drug concentration dependent on the media composition. PKPD analyses determined that Mtb was killed with lower exposures of TBAJ-587 and M3 than expected in ST and FA broth, suggesting previously underestimated potency in these media. Unlike commonly performed in in vitro PKPD studies that solely rely on nominal drug concentrations, our work precisely relates compound activity to actual effective concentrations that are measured over time directly in Mtb cultures, providing improved longitudinal data to feed in silico models for translational research.
Gaps in unimproved house structures, especially in eaves and windows, allow mosquito entry, increasing indoor vector-borne disease transmission. Simple modifications to such houses may reduce human exposure, and insecticide treatment may kill mosquitoes, benefiting all community members. This study evaluated insecticide-treated screening (ITS) for eaves and windows, incorporated with deltamethrin and piperonyl butoxide (PBO), compared to a permethrin and PBO-treated bednet in Tanzania. A randomised Latin-square design (4 × 4) was used in four experimental huts within a large netting cage to allow mosquito recapture inside and outside of huts. Four treatments were evaluated: (1) new (12-month stored) ITS; (2) 12-month naturally-aged ITS; (3) 12-month field-used pyrethroid-PBO bednet (standard of care in Tanzania), and (4) no treatment. The study was performed for 32 nights using 30 mosquitoes per strain, per hut per night. Four laboratory-reared strains were used: malaria vectors (Anopheles arabiensis and An. funestus), dengue vector (Aedes aegypti), and nuisance biting (Culex quinquefasciatus). Recaptured mosquitoes were assessed for mortality at 72 h, blood-feeding, and hut entry. A simulation with a modified mechanistic model tracking Plasmodium falciparum malaria was used to illustrate potential epidemiological impact from these products. Against all mosquito species compared to 12-month aged pyrethroid-PBO-treated bednet, new ITS induced higher mortality [Odds Ratio:2.25(95%Confidence Interval:1.65-3.06),p < 0.0001], and aged-ITS was similar [OR:0.80(95%CI:0.59-1.08),p = 0.141]. Both new and aged ITS significantly (p < 0.0001) reduced mosquito blood-feeding [new OR:0.02(95% CI:0.01-0.03); aged OR:0.09(95%CI:0.05-0.14)] and hut entry [new IRR:0.10(95%CI:0.08-0.13); aged IRR:0.25(95%CI:0.21-0.31)]. Transmission model estimates indicate epidemiological impacts of ITS may supersede pyrethroid-PBO-treated bednets at the population level. The model results indicate impact potency depends on assumed intervention percentage cover, durability, and mosquito bionomics. This study introduces a standardised semi-field bioassay to evaluate ITS, generating entomological data that, for the first time, enabled modelling of its potential impact on malaria transmission. ITS is an efficacious tool for public health as it kills substantial proportions of malaria and dengue vectors, and reduces nuisance biting. Given its simplicity, it should be considered an additional or stand-alone tool for screening unimproved houses.
The reservoir of persistently latently infected cells is a major barrier to a cure for HIV infection. Protein kinase C (PKC) modulators can reverse HIV latency and could thus be useful "Kick" components in "Kick and Kill" approaches to a cure. However, PKC modulators also affect immune cell function, potentially limiting their clinical safety and utility. Here, using PKC isoform inhibitors in models of HIV latency and HIV-negative mononuclear cells, we determined the PKC isoforms involved in PKC modulator-mediated HIV latency reversal and immunomodulation (CD69 and CD4 expression, and inflammatory cytokine production). We found that inhibition of PKC α, β, γ, δ, or θ limited PKC-mediated HIV latency reversal to varying degrees. We also found that combinatorial PKC isoform inhibition significantly limited robust PKC modulator-mediated immune cell surface expression of CD69 and cytokine production. None of the pharmacologic PKC inhibitors affected PKC modulator-mediated downmodulation of T-cell surface CD4 expression. These results provide important insight into the isoforms involved in the various PKC modulator-mediated activities, including HIV latency reversal. Design of next-generation PKC modulators that are more selective for PKC α, β, and θ may allow for the partial functional decoupling of HIV latency reversal from immunomodulatory effects, and lead to safer and more effective PKC modulator-based latency-reversing regimens.IMPORTANCEHIV persists in long-lived, latently infected cellular reservoirs, which prevents the cure of the infection using currently available antiretroviral therapy alone. The "Kick and Kill" strategy proposes the use of latency-reversing agents (LRAs) to induce viral reactivation leading to reservoir elimination. Protein kinase C (PKC) modulators are one of the most potent classes of LRAs and operate through the activation of several PKC isoforms. Here, we demonstrate the contribution of various PKC isoforms to PKC modulator-mediated HIV latency reversal and immunomodulation. We identified PKC α, β, and θ as the isoforms important for latency reversal, while other isoforms, especially broad PKC isoform activation, had greater relative effects on immune cell activation and cytokine release. Together, these results define the pathways required for PKC-mediated HIV latency reversal and other important immunomodulatory effects and will thus inform the development of next-generation isoform-selective PKC modulator LRAs.
We previously identified isoleucine-proline-isoleucine (IPI) as a small molecule associated with extracellular vesicles (EVs) in Cryptococcus. The administration of IPI in vivo resulted in the control of experimental cryptococcal infection through mechanisms that remain unknown. IPI is an inhibitor of dipeptidyl peptidase 4 (Dpp4), an enzyme that regulates insulin and glucose homeostasis in mammals and may also influence pathogenic processes in fungi. Based on these observations, we investigated the biological and pathogenic roles of cryptococcal Dpp4. We demonstrate that Cryptococcus neoformans synthesizes an active, surface-associated Dpp4 that is inhibited by IPI. Deletion of the Dpp4-encoding gene (CNAG_06416) abolished Dpp4 enzymatic activity and resulted in marked physiological alterations, including changes in the proteomic composition of whole cells and EVs, as well as increased accumulation of undivided cells at 37°C both in vitro and in vivo. The dpp4Δ mutant was less lethal than wild-type (WT) cells in a Galleria mellonella infection model. In contrast, increased Dpp4 activity did not enhance lethality, as demonstrated by the ability of WT and 19 high-Dpp4-expressing mutant strains to kill G. mellonella. In a murine model, loss of Dpp4 partially affected fungal virulence, delaying host mortality, and reducing fungal burden, particularly in the brain. This finding is consistent with the observation that dpp4Δ cells were markedly less efficient at crossing endothelial and extracellular matrix layers than WT cells. Collectively, these findings establish DPP4 as an important regulator of cryptococcal physiology and pathogenesis, and support the concept that targeting Dpp4 may offer translational opportunities distinct from conventional antifungal strategies.IMPORTANCECryptococcosis is a life-threatening fungal disease that mainly affects people with weakened immune systems, and current treatments remain limited. In this study, we show that the enzyme dipeptidyl peptidase 4 (Dpp4) plays a central role in the ability of the fungus to cause damage to the host. When Dpp4 is absent, the fungus becomes less virulent, disseminates less efficiently to the brain, and is less likely to kill the host. These findings reveal a previously unrecognized role for Dpp4 in fungal infection and identify this enzyme as a promising target for new therapeutic strategies. By focusing on a fungal pathway distinct from those targeted by existing drugs, this work opens new avenues for developing treatments against a major human fungal pathogen.
A promising antibacterial strategy relies on surfaces that combine contact-killing activity with controlled release, enabling rapid response and long-term reusability. Herein, we report such kill-and-release antibacterial surfaces based on lamellar-organized amphiphilic diblock copolymer thin films. Amphiphilic diblock copolymers comprising a hydrophobic, hydrolyzable poly(tetrahydropyranyl methacrylate) (PTHPMA) block and a hydrophilic poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) block are synthesized via group transfer polymerization and subsequently quaternized with propyl iodide to convert the DMAEMA units into cationic, biocidal quaternary ammonium groups (PQDMAEMA). Upon solvent annealing, the PQDMAEMA-b-PTHPMA thin films self-assemble into lamellae oriented parallel to the substrate, with the biocidal PQDMAEMA block forming the outermost surface layer. Mild hydrolysis converts the hydrophobic THPMA units into hydrophilic methacrylic acid moieties, rendering the copolymer water-soluble and enabling its layer-by-layer removal, renewing the active antibacterial surface. Structural ordering of the diblock copolymers is confirmed by optical and atomic force microscopy, X-ray reflectivity, and grazing incidence small-angle X-ray scattering. The film's self-polishing behavior in water is monitored by ellipsometry for 300 days. The annealed films exhibit effective and durable antibacterial activity, achieving ∼2-log reduction against both Gram-positive and Gram-negative bacteria, both annealed and after 30 days of immersion in pH 7.4 water, demonstrating sustained long-term antimicrobial performance.
This study evaluates the antimicrobial and antibiofilm effects of chlorhexidine and related compounds against S. mutans, focusing on bacterial viability, biofilm formation, and expression of key biofilm genes. Eight compounds were tested for their chemical properties, MICs, and interactions via FIC analyses. Time-kill assays assessed bactericidal activity over 24 h, while cytotoxicity was evaluated in human gingival fibroblasts. Gene expression of biofilm-related genes was analyzed to determine transcriptional modulation. Chlorhexidine gluconate and alexidine showed the strongest antimicrobial activity, with MICs of 2 μg/mL against the reference strain and 4 μg/mL for clinical isolates. Time-kill results demonstrated bacterial reductions from ~7.2 to < 1.0 log CFU/mL in the reference strain but less effect in clinical isolates. Chlorhexidine reduced biofilm biomass by nearly 19% at 48 h, whereas amoxicillin increased biofilm formation by over 12%. Cytotoxicity varied, with proguanil showing high cell viability (90%), while chlorhexidine and alexidine reduced viability to 50-70%. Gene expression analyzes revealed significant downregulation of gtfD and brpA by chlorhexidine and analogs, contrasting with mild upregulation by amoxicillin. These findings highlight chlorhexidine compounds as effective anti-biofilm agents, emphasizing the need for continued exploration of alternatives and combination therapies to enhance dental caries treatment.
Acute hepatopancreatic necrosis disease (AHPND), caused by Vibrio parahaemolyticus, poses a severe threat to global shrimp aquaculture. Reduced susceptibility of aquaculture-associated bacterial pathogens to conventional antibiotics, together with concerns regarding antimicrobial input and environmental exposure, highlights the need for dose-sparing therapeutic strategies. This study investigated the antibiotic-potentiating activity of honokiol (HKL), a plant-derived lignan, in combination with sulfamonomethoxine sodium (SMM-Na) against AHPND. Checkerboard and time-kill assays demonstrated that sub-inhibitory HKL concentrations (32-64 μg/mL) markedly enhanced SMM-Na activity, reducing its minimum inhibitory concentration by 8-32-fold and achieving bactericidal effects in combination. The SMM-Na + HKL combination also significantly inhibited biofilm formation and compromised bacterial membrane integrity, as evidenced by enhanced propidium iodide uptake and scanning electron microscopy, while inducing severe ATP depletion. In Penaeus vannamei challenged with V. parahaemolyticus, dietary administration of low-dose SMM-Na (16 mg/kg) and HKL (32 mg/kg) yielded the highest survival rate (86.6%), substantially reduced hepatopancreatic bacterial load, attenuated histopathological damage, and restored total hemocyte counts. The treatment also upregulated a broad spectrum of immune-related genes (e.g., Alf, Tlr, Lec, Crustin, Lzm, CatB) in the hepatopancreas and mucosal barrier genes (e.g., Muc-1, Muc-4, Muc-5AC, Muc-19) in the intestine. Furthermore, 16S rRNA sequencing indicated that the combination therapy was associated with treatment-related shifts in the intestine microbiota, including increased alpha diversity indices, reduced Vibrio abundance, and altered predicted KEGG functional profiles. Collectively, our results identify HKL as a natural-origin antibiotic potentiator that enhances the efficacy of low-dose SMM-Na against AHPND-causing V. parahaemolyticus. These findings provide proof-of-concept evidence for a dose-sparing combination strategy that may reduce therapeutic SMM-Na input while supporting pathogen control and host recovery in shrimp aquaculture.
This two-phase study evaluated biosecurity vulnerabilities across 100 commercial poultry farms via a field survey and an in vitro assessment of hydrogen peroxide (H2O2) versus a silver nanoparticle-hydrogen peroxide (AgNPs- H2O2) composite. Survey metrics revealed critical baseline deficiencies: 80% of farmers lacked antimicrobial resistance (AMR) awareness, 90% practiced no litter treatment, and 70% of untreated waste was sold directly to aquaculture. Molecular analysis of 192 litter samples verified a 72.4% E. coli prevalence, with Multiple Antibiotic Resistance (MAR) indices peaking at 0.90. Phenotypic profiling showed high resistance to ampicillin (89.9%) and amoxicillin-clavulanic acid (61.2%), whereas colistin demonstrated 100% susceptibility. A significant co-resistance was identified between imipenem and tetracycline (φ = 0.65, p_adj < 0.001) and between cefotaxime and ceftazidime (φ = 0.58, p_adj < 0.001), P < 0.01) after Benjamini-Hochberg FDR correction. Concurrently, the AgNPs- H2O2 composite exhibited superior efficacy with a Minimum Inhibitory Concentration (MIC) of 3.125 µg/mL, proving four-fold more potent than standalone H2O2. Time-kill kinetics demonstrated complete bacterial reduction within 24 h (P < 0.001), successfully suppressing the post-6-hour regrowth observed with H2O2 alone. While this study is limited by its regional geographical scope and the lack of molecular characterization for specific resistance genes, it conclusively identifies veterinary supervision deficits (P < 0.0001) as a driver of extensively drug-resistant (XDR) transmission. Ultimately, the AgNPs- H2O2 composite offers a promising in vitro One Health biosecurity strategy, achieving complete bacterial reduction under controlled conditions at a 75% lower concentration than standalone H2O2, pending field validation.
Crises such as starvation pose a serious threat to microbial populations, prompting cells to adopt survival strategies, such as cooperation or competition. Although cooperation among clones is common, recent studies have shown that yeast cells can kill clonal cells under glucose depletion by secreting autotoxins. Adapted cells survive, whereas non-adapted latecomers are eliminated. Remarkably, this toxin-adaptation (TA) system, which uses the same set of autotoxins, is conserved across distantly related yeast species. This is puzzling because conventional toxin-immunity (TI) systems are prone to exploitation by 'cheaters', cells that benefit from immunity without producing toxins, and typically diverge in an evolutionary arms race. To investigate how this system is maintained, we analysed its evolutionary stability using population dynamics modelling. The system does not evolve in constant environments: cheaters outcompete adaptive cells during continuous starvation, while sensitive cells that produce neither toxin nor immunity dominate in continuous nutrient-rich conditions. However, when the environment switches stochastically between starvation and nutrient-rich phases, with short starvation periods and long nutrient-rich periods, the TA system becomes evolutionarily stable. These findings suggest that fluctuating environments can promote the emergence and long-term maintenance of the TA system, highlighting the critical role of environmental switching in shaping microbial survival strategies.
Systemic multidrug-resistant bacterial infections have become a global public health priority due to the diminished efficacy of standard antibiotic regimens and can lead to sepsis, which is among the leading causes of death (11 million/year) and years of lost life worldwide. We report an effective and well-defined antibiotic equimolar mixture of the platanosides 1-4 that is as effective as its constituent parts and is active against multidrug-resistant Staphylococcus and Streptococcus spp. The platanosides can be easily and inexpensively manufactured in good purity from sycamore tree (Platanus spp.) leaves, making them a viable option as a drug to control multidrug-resistant infections in low- and middle-income countries. The platanosides 1-4 exhibited activity against clinically derived Staphylococcus aureus (methicillin-resistant, vancomycin-resistant, and vancomycin-intermediate) with minimal inhibitory concentration values of 0.5-16 μg/mL. The minimal inhibitory concentration values against clinically derived Streptococcus spp. were 2, 1, 0.06, and 1 μg/mL against Streptococcus mitis, Streptococcus paramsanginis, Streptococcus gordonii, and Streptococcus pneumoniae, respectively. Time-kill studies of the platanosides are reported. The proposed molecular targets and unique polypharmacology of the platanosides 1-4 are also discussed.
Glioblastoma (GBM) is the most aggressive primary brain tumor in adults characterized by poor long-term survival and frequent tumor recurrence, highlighting the urgent need for novel therapeutic strategies. Oncolytic viruses (OVs) preferentially infect and kill cancer cells while stimulating an antitumor immune response. Oncolytic virotherapies have shown encouraging results in preclinical GBM models and some clinical settings. However, high tumor heterogeneity poses a major obstacle. Only a subset of GBM patients responds well, and improvement in survival is usually limited. It is therefore crucial to better understand determinants of OV effectiveness and to consider multiple OVs. Here, we report a comparative analysis of the oncolytic efficacy of 15 clinically relevant viruses across a diverse panel of 14 heterogeneous patient-derived GBM cell lines. Correlation analysis revealed two clusters of viruses with opposing oncolytic activity profiles and opposing preferences for GBM subtypes. Oncolytic activities correlated with expression levels of interferon-, neurodevelopment-, and extracellular matrix-related gene sets, with inverse correlations observed between the two OV groups. Together, these data reveal that diverse viruses share similar determinants of oncolytic activity. Our findings pave the way toward combinatorial or personalized OV therapies in GBM, where tumor subtype could guide selection of the most effective OV.