Hemolytic Effect Research Articles

Discovery of a novel class of rosmarinic acid derivatives as antibacterial agents: Synthesis, structure-activity relationship and mechanism of action

Twenty-seven rosmarinic acid derivatives were synthesized, among which compound RA-N8 exhibited the most potent antibacterial ability. The minimum inhibition concentration of RA-N8 against both S. aureus (ATCC 29213) and MRSA (ATCC BAA41 and ATCC 43300) was found to be 6 μg/mL, and RA-N8 killed E. coli (ATCC 25922) at 3 μg/mL in the presence of polymyxin B nonapeptide (PMBN) which increased the permeability of E. coli. RA-N8 exhibited a weak hemolytic effect at the minimum inhibitory concentration. SYTOX Green assay, SEM, and LIVE/DEAD fluorescence staining assay proved that the mode of action of RA-N8 is targeting bacterial cell membranes. Furthermore, no resistance in wildtype S. aureus developed after incubation with RA-N8 for 20 passages. Cytotoxicity studies further demonstrated that RA-N8 is non-toxic to the human normal cell line (HFF1). RA-N8 also exerted potent inhibitory ability against biofilm formation of S. aureus and even collapsed the shaped biofilm.

Chemical Composition and In Vitro Biological Activity of Two Thymus L. Varieties Growing in Turkey

Thymus kotschyanus var. kotschyanus (TKK) and T. kotschyanus var. glabrescens (TKG) varieties were used as both spice and medicine by the people in Turkey. It was determined that plants’ methanol extracts had the strongest antioxidant, anticholinesterase, antiurease activity and high total phenolic contents. The ethyl acetate and methanol extracts were found to have strong antimicrobial activity. Methanol extracts showed low hemolytic effect against human erythrocytes. It was determined that TKG extract showed higher anti-proliferative effect compared to TKK extract. Both plants extract significantly decreased reactive oxygen species (ROS) generation in cancer cells. It was determined that amounts of chlorogenic and rosmarinic acid compounds were similar in both plants, but apigenin 7-O-neohesperidoside compound was found in higher amounts in TKK. The findings obtained in this study suggest that methanol and ethyl acetate extracts obtained from these two species can be used as antioxidant, anticholinesterase, antimicrobial and antiurease agents. The findings support the traditional use of these species.

Acalypha indica induced acute oxidative haemolysis and methaemoglobinaemia: two case reports

BackgroundHerbal products and traditional remedies are commonly used by individuals worldwide for the management of common ailments, even though most are not without risks. Acalypha indica is a popular medicinal plant consumed in some Asian countries.Case presentationThis case report presents a 40-year-old previously unevaluated Sri Lankan female and her 8-year-old son who presented with severe glucose-6-phosphate dehydrogenase (G6PD) deficiency related acute intravascular oxidative haemolysis and methaemoglobinaemia precipitated by Acalypha indica consumption, successfully managed with supportive care and blood transfusion.ConclusionsThis case highlights the potential hemolytic and methaemoglobinaemic effects of ingesting oxidant herbal products and the importance of considering such exposures in patients presenting with hemolysis and multiorgan involvement, particularly in communities where herbal product intake is popular. Healthcare providers should be aware of the risks associated with traditional remedies and maintain a high index of suspicion to ensure prompt recognition and appropriate management.

Synthesis and In Vitro Antibacterial Evaluation of Mannich Base Nitrothiazole Derivatives

Nitrothiazole derivatives have been reported to exhibit activity against aerobic, anaerobic, and microaerophilic bacteria. This activity profile makes the nitrothiazole compound class an ideal lead source against Mycobacterium tuberculosis, which flourishes in varied environments with different oxygen concentrations. In this work, we investigated six nitrothiazole derivatives for antitubercular activity. The compounds exhibited potent activity, with compounds 9 and 10 possessing an equipotent MIC90 value of 0.24 µM. The compounds were investigated for cytotoxicity against HEK293 cells and hemolysis against red blood cells, and they demonstrated no cytotoxicity nor hemolytic effects, suggesting they possess inherent antitubercular activity.

Promising aryl selenoate derivatives as antileishmanial agents and their effects on gene expression.

Leishmaniasis remains one of the main public health problems worldwide, with special incidence in the poorest populations. Selenium and its derivatives can be potent therapeutic options against protozoan parasites. In this work, 17 aryl selenoates were synthesized and screened against three species of Leishmania (Leishmania major, Leishmania amazonensis, and Leishmania infantum). Initial screening in promastigotes showed L. infantum species was more sensitive to selenoderivatives than the others. The lead Se-(2-selenocyanatoethyl) thiophene-2-carboselenoate (16) showed a half-maximal effective concentration of 3.07 µM and a selectivity index > 32.57 against L. infantum promastigotes. It was also the most effective of all 17 compounds, decreasing the infection ratio by 90% in L. infantum-infected macrophages with amastigotes at 10 µM. This aryl selenoate did not produce a hemolytic effect on human red blood cells at the studied doses (10-100 µM). Furthermore, the gene expression of infected murine macrophages related to cell death, the cell cycle, and the selenoprotein synthesis pathway in amastigotes was altered, while no changes were observed in their murine homologs, supporting the specificity of Compound 16 against the parasite. Therefore, this work reveals the possible benefits of selenoate derivatives for the treatment of leishmaniasis.

Facile fabrication of anticancer peptide coated zeolite imidazole framework for effective treatment of colorectal cancer cells and its apoptosis induction

The low drug resistance, excellent cancer cell targeting, and anticancer benefits of anticancer peptides (ACPs) make them an attractive antitumor drug option. On the other hand, enzymes readily break down in many ACPs after delivery due to their non-specific toxicity. Consequently, drug delivery systems (DDSs) are necessary to avoid the peptides' dissociation and persuade targeted delivery. The cationic amphiphilic anticancer peptide, G(IIKK)3I-NH2 (G3), was developed in this work using a high-performance microfluidic system, which encapsulates the zeolitic imidazolate framework (ZIF-8). The ACPs-loaded nanoparticles (NPs) were efficiently and quickly mixed using the microfluidic system, resulting in NPs with tunable properties. The encapsulation efficacy was high, and the production rate was 120 mL/min. The microfluidic technique-based ZIF-8 fabrication demonstrated better size homogeneity, as evidenced by a decreased polydispersity index (PDI) compared to the conventional technique. The hemolytic effect was much diminished, and a pH-controlled release of the G3 peptides was achieved by encapsulating G(IIKK)3I-NH2 (termed as G3@ZIF-8) into the ZIF-8. Owing to the improved cell absorption by the ZIF-8, G3@ZIF-8 demonstrated a stronger anticancer impact than the free G3 peptide at identical concentrations. In addition to damaging the mitochondrial membrane of HCT 116 colorectal cancer cells, the NPs were able to suppress the proliferation. Consequently, ACP-based cancer therapy can be expanded by developing G3-loaded ZIF-8-NPs, offering an option technique for ACP-based delivery.

A magnetic cross-linked alginate-biobased nanocomposite with anticancer and hyperthermia activities

This research study focuses on a new magnetic nanobiocomposite designed and synthesized by the formation of cross-linked alginate (Alg) hydrogel using CaCl2 cross-linker agent, its modification with flaxseed mucilage hydrogel and silk fibroin (SF) biopolymer extracted, and as well, the in-situ synthesis of Fe3O4 magnetic nanoparticles (Fe3O4 MNPs) in the presence of this biopolymeric substrate. FT-IR, EDX, FE-SEM, XRD, VSM, and TG technical analyses clarified the physical and chemical features of magnetic cross-linked Alg/flaxseed mucilage hydrogel/SF nanobiocomposite. Following the structural characterization of this magnetic natural-based composition, the in-vitro cytotoxicity and hemolysis assay studies with different concentrations resulted in prominent biological outcomes. The survival rates of normal HEK293T cells (95.74%, 94.18%) and breast cancer BT549 cells (79.23%, 77.76%) after 48 and 72 h verified the biocompatibility and anticancer properties of this new nanobiocomposite. Also, less than 5% of the hemolytic effect disclosed its hemocompatibility. Furthermore, a high specific absorption rate value (72.42 W/g) is generated by 1 mg/mL of this magnetic nanobiocomposite. Overall, it can be deduced that magnetic responsive cross-linked Alg/flaxseed mucilage hydrogel/SF nanobiocomposite could functionally perform in magnetic hyperthermia treatment.

Red blood cell membrane-camouflaged gold-core silica shell nanorods for cancer drug delivery and photothermal therapy

Gold core mesoporous silica shell (AuMSS) nanorods are multifunctional nanomedicines that can act simultaneously as photothermal, drug delivery, and bioimaging agents. Nevertheless, it is reported that once administrated, nanoparticles can be coated with blood proteins, forming a protein corona, that directly impacts on nanomedicines’ circulation time, biodistribution, and therapeutic performance. Therefore, it become crucial to develop novel alternatives to improve nanoparticles’ half-life in the bloodstream. In this work, Polyethylenimine (PEI) and Red blood cells (RBC)-derived membranes were combined for the first time to functionalize AuMSS nanorods and simultaneously load acridine orange (AO). The obtained results revealed that the RBC-derived membranes promoted the neutralization of the AuMSS’ surface charge and consequently improved the colloidal stability and biocompatibility of the nanocarriers. Indeed, the in vitro data revealed that PEI/RBC-derived membranes’ functionalization also improved the nanoparticles’ cellular internalization and was capable of mitigating the hemolytic effects of AuMSS and AuMSS/PEI nanorods. In turn, the combinatorial chemo-photothermal therapy mediated by AuMSS/PEI/RBC_AO nanorods was able to completely eliminate HeLa cells, contrasting with the less efficient standalone therapies. Such data reinforce the potential of AuMSS nanomaterials to act simultaneously as photothermal and chemotherapeutic agents.

Hyaluronan-based nano-formulation with mesoporous silica enhances the anticancer efficacy of phloroglucinol against gastrointestinal cancers

Gastrointestinal cancers are one among the most frequently reported cancers where colorectal and gastric cancers ranks third leading cause of cancer related death worldwide. Phloroglucinol, a well-known therapeutic agent for cancer, where its usage has been limited due to its poor water solubility and bioavailability. Hence, our study aims to synthesize and characterize Hyaluronan grafted phloroglucinol loaded Mesoporous silica nanoparticles (MSN-PG-HA). Our nano-formulation hasn't shown any teratogenic effect on Zebrafish embryos, no hemolysis and toxic effect with normal fibroblast cells with a maximum concentration of 300 μg/mL. The cumulative drug release profile of MSN-PG-HA showed a maximum drug release of 96.9 % with 5 mM GSH under redox responsive drug release, which is crucial for targeting cancer cells. In addition, the MSN-PG-HA nanoparticles showed significant a cytotoxic effect against HCT-116, AGS and SW-620 with IC50 values of 86.5 μg/mL, 80.65 μg/mL and 109.255 μg/mL respectively. Also, the cellular uptake assay has shown an increased uptake of FITC-labeled-MSN-PG-HA by HA-receptor mediated endocytosis than FITC-labeled-MSN-PG without HA modification in CD44+ gastrointestinal cancer cell lines. The ability of MSN-PG-HA to target CD44+ cells was further exploited for its application in cancer stem cell research utilizing in silico analysis with various stem cell pathway related targets, in which PG showed higher binding affinity with Gli 1 and the simulation studies proving its effectiveness in disrupting the protein structure. Thus, the findings of our study with nano-formulation are safe and non-toxic to recommend for targeted drug delivery against gastrointestinal cancers as well as its affinity towards cancer stem cell pathway related proteins proving to be a significant formulation for cancer stem cell research.

Mesoporous bioactive scaffolds based on the 14.6Li2O⋅8.6ZrO2⋅67.3SiO2⋅9.5Al2O3 glass-ceramic as drug delivery for bone regeneration

Bioactive scaffolds based on the 14.6Li2O⋅8.6ZrO2⋅67.3SiO2⋅9.5Al2O3 glass-ceramic for use in drug delivery is presented. Powders of the parent glass (212 mm > particle size >38 mm) were heat-treated at 725 °C for 3 h for surface crystallization. They were subjected to a chemical attack with 6 vol% of hydrofluoric acid for 40 s for partial dissolution of the residual glass, and washed with deionised water and calcium carbonate. Structural and microstructural analyses were performed to identify the formed crystalline phases and porosity. Mesopores with 2.05 nm-radius were detected. The immersion method was used to insert alendronate sodium into the scaffolds. The drug delivering capability was evaluated by infrared spectroscopy and thermogravimetric analysis (TG). The FTIR spectra showed the typical functional groups existing in the alendronate sodium, confirming their impregnation into the scaffold's pores. Moreover, the TG thermograms showed loss weights of ∼2% indicating the effective inoculation of the drug into the scaffold. The bioactivity of the material was evaluated through calcium phosphate layer formation after incubation in a simulated body fluid for up to 28 days (37 ± 1 °C) and then analysed by infrared spectroscopy (FTIR). Calcium phosphates were identified after 24 h of immersion indicating the bioactivity of the glass-ceramic. The cytotoxicity and hemocompatibility tests showed that the LZSA glass-ceramic scaffold is not considered toxic to the human body at concentrations below 40 μg/mL and does not show hemolytic effects at all tested concentrations. Thus, the obtained microstructure renders the material promising for use as a drug delivery agent for bone regeneration.

Molecular and haematological investigations on Anaplasma ovis infection in goats in Ahvaz, Iran: Insights into infection rate, haemolytic effect and breed influences.

Anaplasma ovis (A. ovis) is the predominant causative agent of anaplasmosis in goats and sheep in most tropical and subtropical regions of the world. However, there is considerable variation in reported infection rates, breed susceptibility, and controversial findings regarding the haemolytic effects of A. ovis infection in goats. Thus, we investigated the molecular and haematological aspects of A. ovis infection in goats from Ahvaz city. One hundred and fifty apparently healthy goats (74 blacks and 76 Najdi goats) were randomly sampled from six flocks in the Ahvaz suburb during ticks' activity season. Haematological evaluation, smear microscopic (SM) examination and PCR assay were performed to assess A. ovis infection. Additionally, the percentage of parasitemia was determined from blood smears. SM examination revealed that 25.7% of the goats displayed erythrocyte Anaplasma-like inclusion bodies. PCR analysis indicated that 54% of the goats were positive for A. ovis infection (44.6% of blacks and 63.2% of Najdi goats). No significant difference in haematological values was observed between healthy and infected goats based on PCR testing. However, a significant difference in haematological indices was observed between the group with parasitemia level of 0.01-0.02% (SM and PCR positive) compared to the healthy goats (SM and PCR negative), particularly concerning Hb, PCV and RBC count (p < 0.01). When the parasitemia exceeds 0.01%, A. ovis infection may disrupt haematological parameters in infected goats. The high prevalence of A. ovis infection (54%) among the studied goats underscores the importance of giving special attention to implementing necessary measures for disease control in the Ahvaz suburb.

Exploring the feasibility of bacteriocins EntK1 and EntEJ97s in treatment of systemic vancomycin resistant enterococci infections in mice.

Enterocins K1 and EJ97 have specific antimicrobial activity against Enterococcus faecium and Enterococcus faecalis, respectively. The aim of this study was to investigate the utility of these enterocins for in vivo treatment of systemic enterococcal infections. The antimicrobial effect in blood was analysed and compared against the effect in saline. Colony forming unit counts revealed that the enterocins killed all the bacteria within 1 hour. Additionally, the bactericidal effect against E. faecalis was more rapid in blood, indicating a possible synergy between EntEJ97 and blood. Importantly, no enterocin resistant mutants emerged in these experiments. Injecting the enterocins intraperitoneally in an in vivo mouse model and using fluorescence and minimum inhibitory concentration determination to estimate concentrations of the peptides in plasma, indicate that the enterocins exist in circulation in therapeutic concentrations. Alanine aminotransferase detection, and haemolysis analysis indicates that there is no detectable liver damage or haemolytic effect after injection. The study revealed that EntK1 and EntEJ97 are able to kill all bacteria ex vivo in the presence of blood. In vivo experiments determine that the enterocins exist in circulation in therapeutic concentrations without causing liver damage or haemolysis. Future experiments should test these peptides for treatment of infection in a relevant in vivo model.

An ion metathesis strategy for overcoming therapeutic limitations of rose bengal

The therapeutic use of rose bengal (RB) has been limited by its anionic nature, high water solubility, and short half-life. Herein, RB was converted into a group of uniform materials based on organic salts (GUMBOS) via ion metathesis reactions to replace its sodium counterions with distinct cationic antiseptics (i.e., benzyldimethylhexadecylammonium, BZK; cetylpyridinium, C16Py; and chlorhexidine, CHX). The potential use of RB-based GUMBOS as antibacterial agents was investigated against a panel of Gram-positive and Gram-negative bacteria, namely Staphylococcus aureus (S. aureus), methicillin-resistant S. aureus (MRSA), Enterococcus faecalis (E. faecalis), Pseudomonas aeruginosa (P. aeruginosa), and Escherichia coli (E. coli). The micro-broth dilution method was used to determine the minimum inhibitory concentration (MIC) of synthesized GUMBOS as well as their parent compounds and unreacted stoichiometric mixtures. Hemolytic effects were further studied using human red blood cells. When compared to parent compounds and unreacted mixtures, GUMBOS showed equal or improved activity towards the non-resistant strain of S. aureus (i.e., DSM 2569) and E. faecalis. Additionally, [CHX][RB] was found to be active against E. coli with a MIC of 6.4–0.8 nmol mL−1, being 79 and 48 times more potent than RB and the corresponding unreacted mixture. The [CHX][RB] GUMBOS also showed the lowest hemolytic activity among all tested compounds and mixtures (percentage of hemolysis <5%). Overall, these results demonstrated that this ion metathesis strategy can improve the antibacterial activity of RB against Gram-positive bacteria and extend its spectrum of action towards E. coli, which could further contribute to safety improvements in multiple industries.

Design of charge converting lipid nanoparticles via a microfluidic coating technique.

It was the aim of this study to design charge converting lipid nanoparticles (LNP) via a microfluidic mixing technique used for the preparation and coating of LNP. LNP consisting of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC), cholesterol, N-(carbonyl-methoxypolyethyleneglycol-2000)-1,2-distearoyl-sn-glycero-3-phosphoethanolamine (MPEG-2000-DSPE), and various cationic surfactants were prepared at diverging flow rate ratios (FRR) via microfluidic mixing. Utilizing a second chip in the microfluidic set-up, LNP were coated with polyoxyethylene (9) nonylphenol monophosphate ester (PNPP). LNP were examined for their stability in different physiologically relevant media as well as for hemolytic and cytotoxic effects. Finally, phosphate release and charge conversion of PNPP-coated LNP were evaluated after incubation with alkaline phosphatase and on Caco2-cells. LNP produced at an FRR of 5:1 exhibited a size between 80 and 150nm and a positive zeta potential. Coating with PNPP within the second chip led to LNP exhibiting a negative zeta potential. After incubation with 1 U/ml alkaline phosphatase for 4h, zeta potential of the LNP containing 1,2-dioleoyloxy-3-trimethylammonium-propane chloride (DOTAP) as cationic component shifted from - 35mV to approximately + 5mV. LNP prepared with other cationic surfactants remained slightly negative after enzymatic phosphate cleavage. Manufacturing of LNP containing PNPP and DOTAP via connection of two chips in a microfluidic instrument proves to show efficient change in zeta potential from negative to positive after incubation with alkaline phosphatase.

Design and Synthesis of Immunoadjuvant QS-21 Analogs and Their Biological Evaluation.

A series of novel immunoadjuvant QS-21 analogs were synthesized, and their effects on the in vitro hemolysis of red blood cells were evaluated using QS-21 as a control and hemolytic properties as an index. Our results show that all the QS-21 analogs had lower hemolytic effects than QS-21, and their concentrations exhibited a certain quantitative effect relationship with the hemolysis rate. Notably, saponin compounds L1-L8 produced minimal hemolysis and showed lower hemolytic effects, warranting further investigation.

Design of 3D-Photoprintable, Bio-, and Hemocompatible Nonisocyanate Polyurethane Elastomers for Biomedical Implants.

Polyurethanes (PUs) have adjustable mechanical properties, making them suitable for a wide range of applications, including in the biomedical field. Historically, these PUs have been synthesized from isocyanates, which are toxic compounds to handle. This has encouraged the search for safer and more environmentally friendly synthetic routes, leading today to the production of nonisocyanate polyurethanes (NIPUs). Among these NIPUs, polyhydroxyurethanes (PHUs) bear additional hydroxyl groups, which are particularly attractive for derivatizing and adjusting their physicochemical properties. In this paper, polyether-based NIPU elastomers with variable stiffness are designed by functionalizing the hydroxyl groups of a poly(propylene glycol)-PHU by a cyclic carbonate carrying a pendant unsaturation, enabling them to be post-photo-cross-linked with polythiols (thiol-ene). Elastomers with remarkable mechanical properties whose stiffness can be adjusted are obtained. Thanks to the unique viscous properties of these PHU derivatives and their short gel times observed by rheology experiments, formulations for light-based three-dimensional (3D) printing have been developed. Objects were 3D-printed by digital light processing with a resolution down to the micrometer scale, demonstrating their ability to target various designs of prime importance for personalized medicine. In vitro biocompatibility tests have confirmed the noncytotoxicity of these materials for human fibroblasts. In vitro hemocompatibility tests have revealed that they do not induce hemolytic effects, they do not increase platelet adhesion, nor activate coagulation, demonstrating their potential for future applications in the cardiovascular field.

OCULAR INVOLVEMENT IN SNAKEBITE PATIENT: A CASE TO REMEMBER

Introduction : Snake bite cases in Indonesia are not rare with mild to catastrophic consequences on the bitten subject due to its hemolytic and neurotoxic effects. This case represents a rare ocular neurotoxic effect of snake’s venom that cause binocular diplopia and ptosis in a child.&#x0D; Case Illustration : A 9 year-old boy was consulted to ophthalmologist with chief complaint of binocular diplopia. He was hospitalized after being bitten by a snake on his right hand and had an episode of delirious state. Ophthalmologic examination revealed ptosis and exotropia of his left eye in primary position. Further examination of anterior and posterior segments showed good results. His visual acuity was unaffected. Intravenous antivenom was administered and the bite wound was taken care. The boy was discharged from the hospital with a good general condition but still an opthalmoplegia. After a week of follow up the diplopia diminished and his ocular motility was recovered.&#x0D; Discussion : Ocular manifestations in snake bite case might be missed because of delirious state of the patients. Snake venom can cause ptosis and ophthalmoplegia (neurotoxic) along with uveitis, optic neuritis, central retinal artery occlusion or vitreous and retina hemorrhage due to its hemolytic effect. Time interval between the bite and treatment is one of crucial factor that indicate the patient’s prognosis.&#x0D; Conclusion : Thorough examination of anterior to posterior ocular segments is needed in every snake bitten patients to rule out any further ocular complication. An early administration of intravenous antivenom is still a mandatory.

OCULAR INVOLVEMENT IN SNAKEBITE PATIENT: A CASE TO REMEMBER

Introduction : Snake bite cases in Indonesia are not rare with mild to catastrophic consequences on the bitten subject due to its hemolytic and neurotoxic effects. This case represents a rare ocular neurotoxic effect of snake’s venom that cause binocular diplopia and ptosis in a child.&#x0D; Case Illustration : A 9 year-old boy was consulted to ophthalmologist with chief complaint of binocular diplopia. He was hospitalized after being bitten by a snake on his right hand and had an episode of delirious state. Ophthalmologic examination revealed ptosis and exotropia of his left eye in primary position. Further examination of anterior and posterior segments showed good results. His visual acuity was unaffected. Intravenous antivenom was administered and the bite wound was taken care. The boy was discharged from the hospital with a good general condition but still an opthalmoplegia. After a week of follow up the diplopia diminished and his ocular motility was recovered.&#x0D; Discussion : Ocular manifestations in snake bite case might be missed because of delirious state of the patients. Snake venom can cause ptosis and ophthalmoplegia (neurotoxic) along with uveitis, optic neuritis, central retinal artery occlusion or vitreous and retina hemorrhage due to its hemolytic effect. Time interval between the bite and treatment is one of crucial factor that indicate the patient’s prognosis.&#x0D; Conclusion : Thorough examination of anterior to posterior ocular segments is needed in every snake bitten patients to rule out any further ocular complication. An early administration of intravenous antivenom is still a mandatory.

Simultaneous quantification of four hormone therapy drugs by LC-MS/MS: Clinical applications in breast cancer patients

IntroductionAromatase inhibitors such as anastrozole, letrozole, exemestane and selective estrogen down-regulator (SERD) fulvestrant are used mostly to treat breast cancer estrogen receptor positive in post-menopausal women. These drugs are given either through the oral route or by intramuscular injection. They have shown great inter-individual variability with a risk of cardiometabolic disorders. Hence the importance of their therapeutic drug monitoring not only for exposure-efficacy but also exposure-toxicity. We describe here a LC-MS/MS method for the simultaneous quantification of anastrozole, letrozole, exemestane and fulvestrant in human plasma. Material and methodsPlasma samples were prepared by a single-step protein precipitation. The liquid chromatography system was paired with a triple quadrupole mass spectrometer. Quantification were achieved in Multiple Reactions Monitoring mode and the electrospray ionization was in positive mode. ResultsThe method demonstrated consistent analytical performance across various parameters, including linearity, specificity, sensitivity, matrix effect, upper and lower limits of quantification, extraction recovery, precision, accuracy, hemolysis effect, dilution integrity, and stability under different storage conditions, in accordance with established guidelines. The analysis time for each run was 4 min. Calibration curves exhibited linearity within the 1–100 ng/mL range, with correlation coefficients > 0.99 for the four analytes. Plasma concentrations from 42 patients were integrated into the selected calibration. Stability assessments indicated that the four drugs remained stable at − 20 °C for three months, 15 days under refrigeration, up to 7 days at room temperature, and after three freeze-thaw cycles. ConclusionWe have developed and validated this quantitative method for therapeutic drug monitoring of those four hormone therapy drugs:anastrozole, letrozole, fulvestrant and exemestane. This method can be also used for future clinical pharmacokinetics /pharmacodynamics studies.

PVA-Based Films with Strontium Titanate Nanoparticles Dedicated to Wound Dressing Application.

Bioactive materials may be applied in tissue regeneration, and an example of such materials are wound dressings, which are used to accelerate skin healing, especially after trauma. Here, we proposed a novel dressing enriched by a bioactive component. The aim of our study was to prepare and characterize poly(vinyl alcohol) films modified with strontium titanate nanoparticles. The physicochemical properties of films were studied, such as surface free energy and surface roughness, as well as the mechanical properties of materials. Moreover, different biological studies were carried out, like in vitro hemo- and cyto-compatibility, biocidal activity, and anti-biofilm formation. Also, the degradation of the materials' utilization possibilities and enzymatic activity in compost were checked. The decrease of surface free energy, increase of roughness, and improvement of mechanical strength were found after the addition of nanoparticles. All developed films were cyto-compatible, and did not induce a hemolytic effect on the human erythrocytes. The PVA films containing the highest concentration of STO (20%) reduced the proliferation of Eschericha coli, Pseudomonas aeruginosa, and Staphylococcus aureus significantly. Also, all films were characterized by surface anti-biofilm activity, as they significantly lowered the bacterial biofilm abundance and its dehydrogenase activity. The films were degraded by the compost microorganism. However, PVA with the addition of 20%STO was more difficult to degrade. Based on our results, for wound dressing application, we suggest using bioactive films based on PVA + 20%STO, as they were characterized by high antibacterial properties, favorable physicochemical characteristics, and good biocompatibility with human cells.