Search Results (3,148)

The management of acute lymphoblastic leukemia (ALL), the most common pediatric malignancy, critically relies on thiopurine therapy, such as 6-mercaptopurine (6-MP), during the maintenance phase. However, significant inter-individual response variety and high risk of myelosuppression often disrupt therapy efficacy. Pharmacogenetics offer crucial strategies to personalized therapy. While thiopurine methyltransferase (TPMT) was initially the primary focus, the discovery of nudix hydrolase 15 (NUDT15) appears as a more comprehensive determinant of thiopurine intolerance. This review aims to consolidate and critically evaluate the advancement achieved in unraveling the biological mechanism and clinical significance of NUDT15 pharmacogenetics in thiopurine therapy. Foundational studies showed the vital role of NUDT15 in the detoxification of active thiopurines, with common genetic variants (for instance, p. Arg139Cys) significantly disrupting its activity, leading to the accumulation of toxic metabolites. Observational studies consistently associated NUDT15 variants with severe myelosuppression, notably in Asian populations. Recent randomized controlled trials (RCTs) confirmed that NUDT15 genotype-guided dosing effectively reduces thiopurine-induced toxicity without interfering with the therapeutic outcome. Despite these advancements, challenges remain present, including the incomplete characterization of rare variants, limited data in the diverse Asian populations, and the need for standardized integration with metabolite monitoring. In conclusion, NUDT15 pharmacogenetics is essential for improving patient safety and thiopurine dosage optimization in the treatment of ALL. For thiopurine tailored medicine to be widely and fairly implemented, future research should focus on increasing genetic data across different populations, improving the dose adjustment algorithm, and harmonizing therapeutic guidelines. Full article

Background: Fixed-dose combinations have advanced in many therapeutic areas, including otorhinolaryngology, where hearing disorders are increasingly prevalent. Objectives: The present study focuses on developing and evaluating a new capsule combining nicergoline (NIC), piracetam (PIR), and hawthorn extract (HE) for the management of sensorineural hearing loss. Methods: The first phase methodology comprised preformulation studies (DSC, FTIR, and PXRD) to assess compatibility among active substances and excipients. Subsequently, four formulations were prepared and tested for flowability, dissolution behavior in acidic and neutral media, and stability under oxidative, thermal, and photolytic stress. Quantification of the active substances and flavonoids was performed using validated spectrophotometric and HPLC-UV methods. Results: Among the tested variants, the F1 formulation (4.5 mg NIC, 200 mg PIR, 50 mg HE, 2.5 mg magnesium stearate, 2.5 mg sodium starch glycolate, and 240.5 mg monohydrate lactose per capsule) displayed optimal technological properties, superior dissolution in acidic media, and was further selected for evaluation. The antioxidant activity of the formulation was confirmed through the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay, Trolox Equivalent Antioxidant Capacity (TEAC), and iron chelation tests, and was primarily attributed to the flavonoid content of the HE. Acute toxicity tests in mice and rats indicated a high safety margin (LD₅₀ > 2500 mg/kg), while ototoxicity assessments showed no adverse effects on auditory function. Conclusions: The developed formulation displayed good stability, safety, and therapeutic potential, while the applied workflow could represent a model for the development of future fixed-dose combinations. Full article

The increasing demand for rapid, sensitive, and eco-friendly methods for the detection of trace heavy metals in environmental samples, attributed to their serious threats to health and the environment, has spurred considerable interest in the development of sustainable sensor materials. Toxic metal ions, namely, lead (Pb²⁺), cadmium (Cd²⁺), mercury (Hg²⁺), arsenic (As³⁺), and chromium, are potential hazards due to their non-biodegradable nature with high toxicity, even at trace levels. Acute health complications, including neurological, renal, and developmental disorders, arise upon exposure to such metal ions. To monitor and mitigate these toxic exposures, sensitive detection techniques are essential. Pre-existing conventional detection methods, such as atomic absorption spectroscopy (AAS) and inductively coupled plasma-mass spectrometry (ICP-MS), involve expensive instrumentation, skilled operators, and complex sample preparation. Electrochemical sensing, which is simple, portable, and eco-friendly, is foreseen as a potential alternative to the above conventional methods. Carbon-based nanomaterials play a crucial role in electrochemical sensors due to their high conductivity, stability, and the presence of surface functional groups. Biochar (BC), a carbon-rich product, has emerged as a promising electrode material for electrochemical sensing due to its high surface area, sustainability, tunable porosity, surface rich in functional groups, eco-friendliness, and negligible environmental footprint. Nevertheless, broad-spectrum studies on the use of biochar in electrochemical sensors remain narrow. This review focuses on the recent advancements in the development of biochar-based electrochemical sensors for the detection of toxic heavy metals such as Pb²⁺, Cd²⁺, and Hg²⁺ and the simultaneous detection of multiple ions, with special emphasis on BC synthesis routes, surface modification methodologies, electrode fabrication techniques, and electroanalytical performance. Finally, current challenges and future perspectives for integrating BC into next-generation sensor platforms are outlined. Full article

Purpose: To present the findings of our preliminary experience using daily image-guided radiotherapy (IGRT) supported by implanted fiducial markers (FMs) in the radiotherapy of the vaginal cuff, in a cohort of post-surgery endometrial cancer patients. Methods: Patients with vaginal cuff cancer requiring adjuvant radiation with external beams were enrolled. Five patients underwent radiation therapy targeting the pelvic disease and positive lymph nodes, with doses of 50.4 Gy in twenty-eight fractions and a subsequent stereotactic boost on the vaginal vault at a dose of 5 Gy in a single fraction. One patient was administered 30 Gy in five fractions to the vaginal vault. These patients underwent external beam RT following the implantation of three 0.40 × 10 mm gold fiducial markers (FMs). Our IGRT strategy involved real-time 2D kV image-based monitoring of the fiducial markers during the treatment delivery as a surrogate of the vaginal cuff. To explore the potential role of FMs throughout the treatment process, we analyzed cine movies of the 2D kV-triggered images during delivery, as well as the image registration between pre- and post-treatment CBCT scans and the planning CT (pCT). Each CBCT used to trigger fraction delivery was segmented to define the rectum, bladder, and vaginal cuff. We calculated a standard metric to assess the similarity among the images (Dice index). Results: All the patients completed radiotherapy and experienced good tolerance without any reported acute or long-term toxicity. We did not observe any loss of FMs during or before treatment. A total of twenty CBCTs were analyzed across ten fractions. The observed trend showed a relatively emptier bladder compared to the simulation phase, with the bladder filling during the delivery. This resulted in a final median Dice similarity coefficient (DSC) of 0.90, indicating strong performance. The rectum reproducibility revealed greater variability, negatively affecting the quality of the delivery. Only in two patients, FMs showed intrafractional shift > 5 mm, probably associated with considerable rectal volume changes. Target coverage was preserved due to a safe CTV-to-PTV margin (10 mm). Conclusions: In our preliminary study, CBCT in combination with the use of fiducial markers to guide the delivery proved to be a feasible method for IGRT both before and during the treatment of post-operative gynecological cancer. In particular, this approach seems to be promising in selected patients to facilitate the use of SBRT instead of BRT (brachytherapy), thanks to margin reduction and adaptive strategies to optimize dose delivery while minimizing toxicity. A larger sample of patients is needed to confirm our results. Full article

The enzyme γ-glutamyl transpeptidase (GGT), located on the surface of cellular membranes, hydrolyzes extracellular glutathione (GSH) to guarantee the recycling of cysteine and maintain intracellular redox homeostasis. High expression levels of GGT on tumor cells are associated with increased cell proliferation and resistance against chemotherapy. Therefore, GGT inhibitors have potential as adjuvants in treating GGT-positive tumors; however, most have been abandoned during clinical trials due to toxicity. Recent studies indicate marine-derived ovothiols as more potent non-competitive GGT inhibitors, inducing a mixed cell-death phenotype of apoptosis and autophagy in GGT-overexpressing cell lines, such as the chronic B leukemic cell HG-3, while displaying no toxicity towards non-proliferative cells. In this work, we characterize the activity of two synthetic ovothiol analogs, L-5-sulfanylhistidine and iso-ovothiol A, in GGT-positive cells, such as HG-3 and HL-60 cells derived from acute promyelocytic leukemia. The two compounds inhibit the activity of membrane-bound GGT, without altering cell vitality nor inducing cytotoxic autophagy in HG-3 cells. We provide evidence that a portion of L-5-sulfanylhistidine enters HG-3 cells and acts as a redox regulator, contributing to the increase in intracellular GSH. On the other hand, ovothiol A, which is mostly sequestered by external membrane-bound GGT, induces intracellular ROS increase and the consequent autophagic pathways. These findings provide the basis for developing ovothiol derivatives as adjuvants in treating GGT-positive tumors’ chemoresistance. Full article

Microplastics (MPs) are a major contaminant in aquatic environments. Due to their size, they are likely to cause deleterious effects. In this study, we assessed the effects of MPs obtained from two commercially available plastics (PP and PET) in the polychaeta Hediste diversicolor after different periods (4 and 28 days). Toxic effects were assessed by measuring burrowing and spontaneous activities, phase I (CYP1A1, 1A2, and 3A4) activities), conjugation metabolism (GSTs), and antioxidant defense (CAT). Behavioral traits and phase I activities were nonresponsive to the presence of both plastics and for the two durations of exposure, indicating that these organisms are not affected by exposure to MPs and do not metabolize them. Conjugation metabolism was inhibited, which may be explained by the MPs’ capability of inhibiting certain enzymes. CAT activity was increased in animals acutely exposed to PP and decreased in animals chronically exposed to PET. This study shows that PP- and PET-MPs do not cause adverse effects on H. diversicolor. Full article

Background: Cardiovascular diseases, particularly hypertension, and gastrointestinal disorders represent major public health concerns in Mexico. Although a range of pharmacological treatments exists, their use is associated with adverse effects, highlighting the need for safer therapeutic alternatives. Species of the Ipomoea genus are widely employed in Mexican traditional medicine (MTM) for their purgative, anti-inflammatory, analgesic, and sedative properties. Particularly, Ipomoea purpurea is traditionally used as a diuretic and purgative; its leaves and stems are applied topically for their anti-inflammatory and soothing effects. This study aimed to determine their phytochemical composition and to evaluate the associated vasodilatory activity, modulatory effects on intestinal smooth-muscle motility, and toxicological effects of the methanolic (ME-Ip) and dichloromethane (DE-Ip) extracts obtained from the aerial parts of I. purpurea. Methods: The phytochemical composition of the ME-Ip and DE-Ip extracts of I. purpurea was assessed using UPLC-QTOF-MS and GC-MS, respectively. For both extracts, the vasodilatory activity and effects on intestinal smooth muscle were investigated using ex vivo models incorporating isolated rat aorta and ileum, respectively, whereas acute toxicity was evaluated in vivo. Results: Phytochemical analysis revealed, for the first time, the presence of two glycosylated flavonoids within the Ipomoea genus; likewise, constituents with potential anti-inflammatory activity were detected. The identified compounds in I. purpurea extracts may contribute to the vasodilatory, biphasic, and purgative effects observed in this species. The EC₅₀ values for the vasodilatory effects of the methanolic (ME-Ip) and dichloromethane (DE-Ip) extracts were 0.80 and 0.72 mg/mL, respectively. In the initial phase of the experiments on isolated ileal tissues, both extracts induced a spasmodic (contractile) effect on basal motility, with ME-Ip exhibiting higher potency (EC₅₀ = 27.11 μg/mL) compared to DE-Ip (EC₅₀ = 1765 μg/mL). In contrast, during the final phase of the experiments, both extracts demonstrated a spasmolytic effect, with EC₅₀ values of 0.43 mg/mL for ME-Ip and 0.34 mg/mL for DE-Ip. In addition, both extracts exhibited low levels of acute toxicity. Conclusions: The phytochemical profile and the vasodilatory and biphasic effects of the I. purpurea extracts explain, in part, the use of I. purpurea in MTM. The absence of acute toxic effects constitutes a preliminary step in the toxicological safety assessment of I. purpurea extracts and demonstrates their potential for the development of phytopharmaceutic agents as adjuvants for the treatment of cardiovascular and gastrointestinal disorders. Full article

Nano- (NPs) and microplastics (MPs) are ubiquitous and raising concerns about their toxicity. A popular model for studying acute toxicity is Danio rerio. This study investigated the acute toxicity in FET test of polystyrene nanoparticles (500 nm, nanoPS) at different concentrations (0.01, 0.1, and 0.2 mg/mL), with different surface groups (non-modified, amine, carboxyl) and discuss the toxicological contribution of commercially added compounds. Different behavioural tests were used to investigate the neurotoxicity of nanoPS and sodium azide: coiling assay test, light–dark preference test, and colour preference test. Sodium azide and other preservatives are often present in commercially available NP and MP solutions frequently used in microplastic toxicity tests, but their effects on the results remain largely unknown. In the FET test, nanoPS did not increase mortality or affect the heart rate or body length. A higher hatching rate was observed at 48 hpf. Although nanoPS showed no acute toxicity, behavioural tests revealed subtle neurotoxic effects (changes in colour preference), suggesting a potential impact on neurological function. Additionally, sodium azide exhibited toxicity, indicating that additives may confound toxicity assessments. This highlights the need for careful consideration of preservatives in nanoparticle research to avoid misleading conclusions. Full article

Strobilurins are a prominent class of fungicides capable of entering aquatic environments via runoff and leaching from the soil. Findings from previous studies suggest that strobilurins are highly toxic in aquatic environments, and evidence of acute developmental toxicity and altered behavioral responses have been emphasized. The objective here was to determine the effects of a new strobilurin, metyltetraprole (MTP), on zebrafish using developmental endpoints, gene expression, and behavioral locomotor assays. We hypothesized that MTP would cause developmental toxicity and induce hyperactivity in zebrafish (Danio rerio). To test this, developing zebrafish embryos/larvae were exposed to environmentally relevant levels of MTP (0.1, 1, 10, and 100 µg/L) until 7 days post-fertilization. Survival percentages did not differ among the treatment groups. No change in reactive oxygen species production was detected, but two genes involved in the mitochondrial electron transport chain (mt-nd3 and uqcrc2) were altered in abundance following MTP exposure. Moreover, the highest concentration (100 µg/L) of MTP caused notable hyperactivity in the zebrafish in the visual motor response test. Overall, results from this study increase our knowledge regarding sub-lethal effects of MTP, helping inform risk assessment for aquatic environments. Full article

Tebuconazole (TBZ), a triazole-class fungicide widely used in agriculture, is frequently detected in aquatic environments due to runoff and leaching, where it poses a threat to non-target aquatic organisms. This study investigates the acute toxicity of TBZ on juvenile rainbow trout (Oncorhynchus mykiss), a commercially important cold-water fish species. The 96 h LC₅₀ value was determined to be 9.05 mg/L using probit analysis. In addition to mortality, the physiological responses of fish exposed to both LC₅₀ and maximum tolerance concentration (MTC; 6 mg/L) were evaluated through haematological and histological assessments. TBZ exposure significantly suppressed key haematological parameters, particularly WBC, RBC, HGB, HCT, and LYM, indicating immunosuppression and potential hypoxia. Histological examination revealed progressive and regressive damage in gill tissues, including epithelial lifting, hyperplasia, and hypertrophy, which were more severe in the LC₅₀ group. These alterations were quantified using a semi-quantitative scoring system. Additionally, significant changes in biochemical parameters such as ALT, AST, creatinine, total protein, and glucose levels were observed, further indicating hepatic and renal dysfunctions induced by TBZ exposure. The findings demonstrate that TBZ exposure induces substantial physiological and structural impairments in rainbow trout, highlighting the importance of assessing the ecological risks of fungicide contamination in aquatic environments. The study also provides a dose–response model that can be used to estimate mortality risk in aquaculture operations exposed to TBZ. Full article

Povidone-iodine (PVP-I), a widely used aquaculture disinfectant, remains poorly understood in terms of sublethal toxicity and damage reversibility. This study employed Macrobrachium rosenbergii as the model organism to evaluate the acute toxicity and sublethal effects of PVP-I through a 4-day exposure experiment followed by a 7-day depuration period. Acute toxicity tests enabled the determination of 24–96 h median lethal concentrations (LC₅₀), with the 96 h LC₅₀ being 5.67 mg/L and the safe concentration (SC) being 1.37 mg/L. Based on this, three sublethal concentrations (1.14, 1.89, and 2.84 mg/L) were tested over a 4-day exposure followed by a 7-day depuration period. Investigated endpoints included gill ultrastructure, apoptosis, and antioxidant and immune-related gene expression. Subacute exposure at 1.89 and 2.84 mg/L induced mitochondrial vacuolization, upregulated apoptosis-related genes (Cyt-c, Caspase-3, Bok), and downregulated antioxidant gene expression (SOD, CAT, GSH-Px). The high-concentration group also showed sustained Toll-like receptor (Toll) gene overexpression and acid phosphatase (ACP) gene suppression. After depuration, antioxidant gene expression normalized; however, apoptotic markers in gill tissue remained impaired. Overall, high PVP-I concentrations cause irreversible gill damage via mitochondrial-mediated apoptosis, whereas lower concentrations (≤1.14 mg/L) allow for greater recovery. These results offer crucial toxicodynamic insights for safer PVP-I use and risk assessment in M. rosenbergii aquaculture. Full article

Background/Objectives: Oncogenic KRAS drives ~30% of solid tumours, yet the only approved G12C-specific drugs benefit ≈ 13% of KRAS-mutant patients, leaving a major clinical gap. We sought mutation-agnostic natural ligands from Ziziphus lotus, whose stereochemically rich phenolics may overcome this limitation by occupying the SI/II (Switch I/Switch II) groove and locking KRAS in its inactive state. Methods: Phytochemical mining yielded five recurrent phenolics, such as (+)-catechin, hyperin, astragalin, eriodictyol, and the prenylated benzoate amorfrutin A, benchmarked against the covalent inhibitor sotorasib. An in silico cascade combined SI/II docking, multi-parameter ADME/T (Absorption, Distribution, Metabolism, Excretion, and Toxicity) filtering, and 100 ns explicit solvent molecular dynamics simulations. Pharmacokinetic modelling predicted oral absorption, Lipinski compliance, mutagenicity, and acute-toxicity class. Results: Hyperin and astragalin showed the strongest non-covalent affinities (−8.6 kcal mol⁻¹) by forging quadridentate hydrogen-bond networks that bridge the P-loop (Asp30/Glu31) to the α3-loop cleft (Asp119/Ala146). Catechin (−8.5 kcal mol⁻¹) balanced polar anchoring with entropic economy. ADME ranked amorfrutin A the highest for predicted oral absorption (93%) but highlighted lipophilic solubility limits; glycosylated flavonols breached Lipinski rules yet remained non-mutagenic with class-5 acute-toxicity liability. Molecular dynamics trajectories confirmed that hyperin clamps the SI/II groove, suppressing loop RMSF below 0.20 nm and maintaining backbone RMSD stability, whereas astragalin retains pocket residence with transient re-orientation. Conclusions: Hyperin emerges as a low-toxicity, mutation-agnostic scaffold that rigidifies inactive KRAS. Deglycosylation, nano-encapsulation, or soft fluorination could reconcile permeability with durable target engagement, advancing Z. lotus phenolics toward broad-spectrum KRAS therapeutics. Full article

Euphorbia hirta L. is traditionally used to treat tumors and has demonstrated anticancer effects. This study evaluated the phytochemical composition, toxicity, and antitumor activity of saline extract (SE) from E. hirta leaves in mice. Phytochemical analysis included thin layer chromatography, high-performance liquid chromatography, and quantification of phenols, flavonoids, and proteins. Acute toxicity (2000 mg/kg) assessed mortality, hematological, biochemical, histological parameters, water/feed intake, and body weight. Genotoxicity was evaluated via comet and micronucleus assays. Antitumor activity was tested in vitro and in vivo on sarcoma 180. SE contained 107.3 mg GAE/g phenolics and 22.9 mg QE/g flavonoids; the presence of gallic and ellagic acids was detected. Protein concentration was 12.16 mg/mL with lectin activity present. No mortality, organ damage, or genotoxic effects occurred in toxicity tests. SE demonstrated in vitro cytotoxicity against sarcoma cells (IC₅₀: 10 µg/mL). In vivo, SE (50–200 mg/kg) reduced tumor weight by 70.2–72.3%. SE modulated IL-2, IL-4, IL-6, IL-17, IFN-γ, and TNF-α in tumor environment. Tumors showed inflammatory infiltrate, necrosis, and fibrosis after treatment. These findings position the extract as a promising candidate for further development as a safe, plant-based antitumor agent. Full article

Mitochondria are critical for cellular energy, and while large deletions in their genome (mtDNA) are linked to primary mitochondrial diseases, their significance in cancer is less understood. Given cancer’s metabolic nature, investigating mtDNA deletions in tumors at various stages could provide insights into disease origins and treatment responses. In this study, we analyzed 148 bone marrow samples from 129 pediatric patients with B-cell (B-ALL) and T-cell (T-ALL) acute lymphoblastic leukemia at diagnosis, remission, and relapse using long-range PCR, next-generation sequencing, and the Splice-Break2 pipeline. Both T-ALL and B-ALL exhibited significantly more mtDNA deletions than did the controls, with T-ALL showing a ~100-fold increase and B-ALL a ~15-fold increase. The T-ALL samples also exhibited larger deletions (median size > 2000 bp) and greater heterogeneity, suggesting increased mitochondrial instability. Clustering analysis revealed distinct deletion profiles between ALL subtypes and across disease stages. Notably, large clonal deletions were detected in some B-ALL remission samples, including one affecting up to 88% of mtDNA molecules, which points toward treatment-driven selection or toxicity. A multivariate analysis confirmed that disease type, timepoint, and WHO subtype significantly influenced mtDNA deletion metrics, while age and gender did not. These findings suggest that mtDNA deletion profiling could serve as a biomarker for pediatric ALL and may indicate mitochondrial toxicity contributing to late effects in survivors. Full article

Pasteurella multocida (Pm) is a zoonotic pathogen that poses a significant threat to animal health and causes substantial economic losses, further aggravated by rising tetracycline resistance. To restore the efficacy of tetracyclines to Pm, we evaluated the synergistic antibacterial activity of doxycycline combined with metformin, an FDA-approved antidiabetic agent. Among several non-antibiotic adjuvant candidates, metformin exhibited the most potent in vitro synergy with doxycycline, especially against capsular serogroup A strain (PmA). The combination demonstrated minimal cytotoxicity and hemolysis in both mammalian and avian cells and effectively inhibited resistance development under doxycycline pressure. At 50 mg/kg each, the combination of metformin and doxycycline significantly reduced mortality in mice and ducks acutely infected with PmA (from 100% to 60%), decreased pulmonary bacterial burdens, and alleviated tissue inflammation and damage. Mechanistic validation confirmed that metformin enhances membrane permeability in Pm without compromising membrane integrity, dissipates membrane potential, increases intracellular doxycycline accumulation, and downregulates the transcription of the tetracycline efflux gene tet(B). Morphological analyses further revealed pronounced membrane deformation and possible leakage of intracellular contents. These findings highlight metformin as a potent, low-toxicity tetracycline adjuvant with cross-species efficacy, offering a promising therapeutic approach for managing tetracycline-resistant Pm infections. Full article