Vesicular Systems Research Articles

Vesicular Carriers for Improved Oral Anticoagulation Competence of Rivaroxaban: In Vitro and In Vivo Investigation

Rivaroxaban is an anticoagulant for avoidance and therapy of thromboembolic disorders. Unfortunately, oral bioavailability of rivaroxaban is compromised with dose increments. Accordingly, the aim was to test nano-vesicular lipid systems for improved oral anticoagulation activity of rivaroxaban. Rivaroxaban loaded niosomes, bilosomes and spanlastic formulations were prepared. The prepared systems were assessed in terms of particle size, zeta potential, transition electron microscopic features (TEM), entrapment efficiency, in-vitro drug release, and in-vivo anticoagulation performance in rats. The prepared vesicular systems exposed spherical negatively charged vesicles with mean particle size values between 136.6 nm to 387.9 nm depending on the composition. Rivaroxaban was efficiently entrapped in the vesicular systems with entrapment efficiency values ranging from 92.4% to 94.0%. Rivaroxaban underwent sustained release from the fabricated vesicular systems. The in vivo performance of the tested preparation revealed significant enhancement of the anticoagulation parameters. This was manifested from the prolonged clotting time, and prothrombin time. Moreover, the cut tails of the examined rats receiving the formulated nano-systems exposed a lengthy tail bleeding time compared to those receiving the un-processed rivaroxaban aqueous dispersion. In Conclusion, niosomes, bilosomes and spanlastic nano-dispersions have a potential to overwhelm the oral anticoagulation efficiency of rivaroxaban with spanlastic ranked as best.Graphical

A Review: Bilosomes as Nanocarriers

Abstract: Liposomes and niosomes, two vesicular carriers that are prospective candidates for drug delivery, have been used in numerous formulations. New research in this area has led to the development of a ‘niosome-like’ colloidal carrier termed bilosomes. Bilosomes have been designed as prospective vesicular carriers to deliver targeted drugs via parenteral, transdermal, and oral routes. These innovative vesicular systems, based on bile salts, have been discussed in detail in the current review. The review addresses the composition of bilosomes, their creation and characterization processes. Previous research on bilosomes has been compiled, along with their applications and advantages over more traditional nanocarriers such as liposomes and niosomes. It also emphasizes the utilization of bilosomes and their stability.

Lipid-Based Nanoformulations for Drug Delivery: An Ongoing Perspective

Oils and lipids help make water-insoluble drugs soluble by dispersing them in an aqueous medium with the help of a surfactant and enabling their absorption across the gut barrier. The emergence of microemulsions (thermodynamically stable), nanoemulsions (kinetically stable), and self-emulsifying drug delivery systems added unique characteristics that make them suitable for prolonged storage and controlled release. In the 1990s, solid-phase lipids were introduced to reduce drug leakage from nanoparticles and prolong drug release. Manipulating the structure of emulsions and solid lipid nanoparticles has enabled multifunctional nanoparticles and the loading of therapeutic macromolecules such as proteins, nucleic acid, vaccines, etc. Phospholipids and surfactants with a well-defined polar head and carbon chain have been used to prepare bilayer vesicles known as liposomes and niosomes, respectively. The increasing knowledge of targeting ligands and external factors to gain control over pharmacokinetics and the ever-increasing number of synthetic lipids are expected to make lipid nanoparticles and vesicular systems a preferred choice for the encapsulation and targeted delivery of therapeutic agents. This review discusses different lipids and oil-based nanoparticulate systems for the delivery of water-insoluble drugs. The salient features of each system are highlighted, and special emphasis is given to studies that compare them.

A Comprehensive Review on Oleic Acid Vesicles: A Novel Approach to Drug Delivery.

The implementation of several innovative drug delivery technologies has made medication distribution more focused and managed in recent years. These days, a vesicular drug delivery system defines the rate of distribution and the site of action in order to improve the action and increase patient compliance; there are various kinds of newly developed vesicular drug delivery systems, including transferosomes, niosomes, aquasomes, ufasomes, pharmacosomes, and phytosomes. Ufasomes are unsaturated fatty acid vesicles with a limited pH range of 7 to 9. They are a suspension of closed lipid bilayers made of fatty acids and their ionized species. The hydrocarbon tails of fatty acid molecules are oriented toward the membrane's inner core, and their carboxyl groups are in contact with water. The two fatty acids that are most frequently employed in the ufasomes' manufacturing process are oleic and linoleic acids. It is a common practice to produce fatty acid vesicles via the thin film hydration process. The manufacture of stable ufasomes is mostly dependent on the choice of fatty acids, amount of cholesterol, pH range, buffer, etc. This article goes into additional detail regarding unsaturated fatty acids' characteristics, benefits, and drawbacks.

Absolute Membrane Protein Abundance of P-gp, BCRP and MRPs in Term Human Placenta Tissue and Commonly Used Cell Systems: Application in PBPK Modeling of Placental Drug Disposition.

The placenta acts as a barrier, excluding noxious substances whilst actively transferring nutrients to the fetus, mediated by various transporters. This study quantified the expression of key placental transporters in term human placenta (n=5) and BeWo, BeWo b30, and JEG-3 placenta cell lines. Combining these results with pregnancy physiologically-based pharmacokinetic (PBPK) modeling, we demonstrate the utility of proteomic analysis for predicting placental drug disposition and fetal exposure. Using targeted proteomics with QconCAT standards, we found significant expression of P-gp, BCRP, MRP2, MRP4, and MRP6 in the human placenta (0.05 - 0.25 pmol/mg membrane protein) with only regional differences observed for P-gp. Unexpectedly, both P-gp and BCRP were below the limit of quantification in the regularly used BeWo cells, indicating that this cell line may not be suitable for the study of placental P-gp and BCRP-mediated transport. In cellular and vesicular overexpression systems, P-gp and BCRP were detectable as expected. Vesicle batches showed consistent P-gp expression correlating with functional activity (N-methyl-quinidine (NMQ) transport). However, BCRP activity (Estrone 3-sulfate (E1S) transport) did not consistently align with expression levels. Incorporating in vitro transporter kinetic data, along with placental transporter abundance, into a PBPK model enabled the evaluation of fetal exposure. Simulation with a hypothetical drug indicated that estimating fetal exposure relies on the intrinsic clearances of relevant transporters. To minimize interlaboratory discrepancies, expression data was generated using consistent proteomic methodologies in the same lab. Integration of this data in pregnancy-PBPK modeling offers a promising tool to investigate maternal, placental and fetal drug exposure. Significance Statement This study quantified the expression of key transporters in human placenta and various placental cell lines, revealing significant expression variations. By integrating these data with PBPK modeling, the study highlights the importance of transporter abundance data in understanding and predicting placental drug disposition.

Atorvastatin loaded glycerosomal patch as an effective transdermal drug delivery: optimization and evaluation.

Aim: The study explores glycerosomes as effective vesicular systems for transdermal delivery of atorvastatin (ATO) to overcome drawbacks related to its oral administration.Methodology: The objectives of this study were to formulate, by thin-film hydration method, optimize using definitive screening design and evaluate ATO-loaded glycerosomes (ATOG) which were then incorporated into patch followed by the evaluation of glycerosomes containing different concentration of glycerol.Results & discussion: Vesicle size, Polydispersity index (PDI), zeta potential, entrapment efficiency and loading capacity of spherical ATOG (0-30%w/w) showed 137.3-192d.nm, 0.292-0.403, -3.81 to-6.76mV, 80.03-92.77% and 5.80-6.40%, respectively. In-vitro release study showed sustained release, increased skin permeability and better cell viability than pure drug. ATOG patches showed greater skin permeability than pure drug and ATO-liposomal patches.Conclusion: The study concludes that ATOGs are promising for effective transdermal delivery.

Exploring Applications of Flexible Vesicular Systems as Transdermal Drug Delivery.

Deformable lipidic-nano carriers are a category of advanced liposomal formulations. Deformable lipidic-nano carriers have a specific character to transform by rearranging the lipidic backbone to squeeze themself through a pore opening ten times smaller than their diameter when exposed to a variable condition like hydration gradient as these have potentially been used as a non-invasive delivery system to transdermally migrate various therapeutic agents for over three decades. Despite their vast application in transdermal drug delivery system, non-uniformity to express their chemical nature still exist and authors use various terms synonymously and interchangeably with each other. The present study delineates the terminologies used to express different derived deformable vesicular carriers to harmonize the terminological use. It also includes the effectiveness of deformable nanocarriers like Transferosomes, Ethosomes, Menthosomes, Invasomes, and Glycerosomes in skin conditions like basal cell carcinoma, fungal and viral infections, and hyperpigmentation disorders, along with others. Various review and research articles were selected from the 'Pubmed' database. The keywords like Transferosomes, Flexi-vesicular system, ultra-deformable vesicles, and nano-vesicular systems were used to extract the data. The data was reviewed and compiled to categorically classify different flexible vesicular systems. The composition of the different vesicular systems is identified and a report of various pathological conditions where the use of flexible lipid nanocarrier systems was implemented is compiled. The review also offers suggestive approaches where the applicability of these systems can be explored further.

Clarithromycin-tailored cubosome: A sustained release oral nano platform for evaluating antibacterial, anti-biofilm, anti-inflammatory, anti-liver cancer, biocompatibility, ex-vivo and in-vivo studies

The clinical implication of clarithromycin (CLT) is compromised owing to its poor solubility and, subsequently, bioavailability, unpalatable taste, rapid metabolism, short half-life, frequent dosing, and adverse effects. The present investigation provides an innovative sustained-release oral drug delivery strategy that tackles these challenges. Accordingly, CLT was loaded into a cubosome, a vesicular system with a bicontinuous cubic structure that promotes solubility and bioavailability, provides a sustained release system combating short half-life and adverse effects, masks unpleasant taste, and protects the drug from destruction in gastrointestinal tract (GIT). Nine various formulas were fabricated using the emulsification method. The resulting vesicles increased the encapsulation efficiency (EE %) from 57.64 ± 0.04 % to 96.80 ± 1.50 %, the particle size (PS) from 147.30 ± 21.77 nm to 216.61 ± 5.37 nm, and the polydispersity index (PDI) values ranged from 0.117 ± 0.024 to 0.278 ± 0.073. The zeta potential (ZP) changed from −20.65 ± 2.01 mV to −33.98 ± 2.60 mV. Further, the release profile exhibited a dual release pattern within 24 h., with the percentage of cumulative release (CR %) expanding from 30.06 ± 0.42 % to 98.49 ± 2.88 %, optimized formula was found to be CC9 with EE % = 96.80 ± 1.50 %, PS = 216.61 ± 5.37 nm, ZP = −33.98 ± 2.60 mV, PDI = 0.117 ± 0.024, CR % = 98.49 ± 2.88 % and IC50 of 0.74 ± 0.19 µg/mL against HepG-2 cells with scattered unilamellar cubic non-agglomerated vesicles. Additionally, it exhibited higher anti-MRSA biofilm, relative bioavailability (2.8 fold), and anti-inflammatory and antimicrobial capacity against Pseudomonas aeruginosa, Escherichia coli, Bacillus subtilis, and Staphylococcus aureus compared to free CLT. Our data demonstrate that cubosome is a powerful nanocarrier for oral delivery of CLT, boosting its biological impacts and pharmacokinetic profile.

Proniosomes Nanoparticle for the Treatment of Peripheral Arterial Disease.

The common symptom of systemic atherosclerosis is peripheral arterial disease (PAD), which occurs when the artery lumen in the lower extremities gradually becomes blocked by atherosclerotic plaque. The most frequent symptom of lower extremity PAD, called "vascular claudication," which is pain experienced when walking. Partial or total blockage of the peripheral arteries in the upper and lower limbs is called PAD. The danger of death from concurrent coronary artery and cerebrovascular atherosclerosis outweighs the risk of amputation. However, niosomes have issues with fusion, aggregation, leakage, vesicle sedimentation, and difficulty in sterilizing. A more recent strategy known as pro-vesicular carriers was used to solve these issues. The formulations in Proniosomes are dry and anhydrous, protected with a non-ionic surfactant that serves as a carrier when combined with water. Formulation prepared by organic solvent, surfactant, cholesterol, other components and hydration medium. Coacervation Phase separation Technique used for proniosome Nanoparticle. Box Bhenken Design is used for optimization batches. In this context, we shall discuss the development of Proniosome for the treatment of peripheral arterial diseases. From here, we know that proniosome nanoparticles is pro vesicular system good characteristics and effectiveness for treating peripheral arterial diseases. Proniosomes may be created using various techniques, which may impact how they develop along with the drug's characteristics. They increase the drug's stability while being delivered while being entrapped. They don't need particular conditions for handling, protection, storage, or industrial manufacturing.

Niosomal as Potential Vesicular Drug Nano-carriers for the Treatment of Tuberculosis (TB)

Targeted drug delivery systems are employed to administer pharmaceutical medication, facilitating the precise delivery of drugs to specific diseased areas. Various delivery methods utilize carriers such as antibodies, transdermal patches, biodegradable polymers, nanoparticles (NPs), liposomes, niosomes, and microspheres. Niosomes, on the other hand, represent a promising and innovative category of vesicular systems. Niosomes are vesicles formed by hydrating a combination of nonionic surfactants (NIOs) and cholesterol. These nonionic surfactant carriers serve as carriers for both lipophilic and amphiphilic drugs. In the drug delivery system using niosomes, the medication is enclosed within a vesicle. The niosomes in tuberculosis (TB) possess biodegradable and biocompatible properties, are nonimmunogenic, and demonstrate versatility in their structural composition. It is a serious and potentially contagious disease originating from the bacteria, Mycobacterium tuberculosis. In a recent update, the WHO still estimated that the number of TB cases was 9.9 million in 2022. The use of niosomes improves the treatment of TB through the use of much more advanced technology and advanced drug nanocarriers. The main aim of this review paper is to summarize the structural compositions of niosomes with silent features and various preparation methods, as well as to complete the discussion about tuberculosis and its treatment/diagnosis. Finally, the comparison of niosomes with liposomes and their current applications in treating TB with several niosomal-drug carriers and treatment with niosomal formulations was performed.

A one-platform comparison study of brinzolamide-loaded liposomes, niosomes, transfersomes, and transniosomes for better management of glaucoma

Ocular drug delivery presents significant challenges due to various anatomical and physiological barriers. Ultradeformable vesicles have emerged as better vesicular systems for achieving deeper corneal penetration and enhanced ocular bioavailability. This research aims to develop a hybrid vesicular system with improved deformability and compare it to conventional vesicular carriers. The ultradeformable vesicle, termed “transniosomes,” is a combination of niosomes, liposomes, and transfersomes, loaded with brinzolamide as model drug. The brinzolamide-loaded transniosomes (BRZ-TN) was formulated and compared with different vesicular systems through in vitro, ex vivo, and in vivo characterizations. The optimized BRZ-TN demonstrated a vesicle size of 112.06 ± 4.13 nm and an entrapment efficiency of 93.63 ± 0.30 %. With a deformability index of 6.405, the BRZ-TN exhibited a permeability of 86.68 ± 2.51 % over 10 h, which is approximately 1.3 times higher than other conventional vesicular systems. Additionally, the BRZ-TN showed a drug flux of 0.247 ± 0.01 mg/cm2/h and an apparent permeability of 0.09 ± 1.21 cm/s. Pre-clinical experiments confirmed the superiority of the optimized BRZ-TN, achieving a 37 % reduction in intraocular pressure (IOP), post 6hr of administration, indicating its prolonged therapeutic effect and improved ocular bioavailability. The findings of this study suggest that transniosomes are superior to other carriers and hold great promise as a nanocarrier for ocular drug delivery.

A COMPREHENSIVE REVIEW ON ETHOSOMAL GEL

Ethosomal systems are newer lipid vesicular carriers that have been around for 20 years, but over that period they have grown significantly as a means of transdermal drug delivery. They have a sizable amount of ethanol in them. These nanocarriers carry medicinal substances with various physicochemical qualities throughout the skin and deep skin layers. Since they were created in 1996, ethosomes have undergone substantial investigation; new substances have been added to their original composition, creating new varieties of ethosomal systems. These innovative carriers, which can be added to gels, patches, and lotions, are prepared using several novel methods. In addition to clinical trials, many in vivo models are employed to assess the effectiveness of dermal/transdermal administration. This review focuses on different generation of ethosomes and their comparison with other conventional liposomes. KEY WORDS: Ethosomes, Transdermal drug delivery, Lipid vesicular systems,

Nano-vesicular systems for melanocytes targeting and melasma treatment: In-vitro characterization, ex-vivo skin retention, and preliminary clinical appraisal

Melasma represents an acquired melanogenesis disorder resulting in skin’s hyperpigmentation effect. Although several approaches are adopted for melasma treatment, nanotechnology presents the most convenient one. Therefore, the present work aimed to formulate and characterize three nano-vesicular systems namely, liposomes, penetration enhancer containing vesicles (PEVs) and invasomes to enhance the topical delivery of the skin whitening agent; alpha arbutin (α-arbutin) for the treatment of melasma. Liposomes were prepared according to a 23 full factorial design and the selected formula was further employed for the preparation of PEVs and invasomes. Results showed that the three vesicular systems exhibited nano-sizes ranging from 151.95 to 672.5 nm, negative charges ranging from −12.50 to −28.20 mV, high entrapment efficiencies ranging from 80.59 to 99.53 %, good stability and prolonged-release of α-arbutin for 24 h after dispersion in hydrogel form. The deposition study from the vesicular hydrogel confirmed their effectiveness for the drug’s accumulation in the skin reaching an average of 1.6-fold higher in the stratum corneum, 1.6–1.8-fold higher in the epidermis, and 1.6–1.8-fold higher in the dermis compared to the free drug dispersion in hydrogel. A preliminary clinical split-face study on patients suffering from melasma revealed that α-arbutin-loaded liposomes and PEVs in hydrogel forms showed better clinical outcomes compared to the free α-arbutin hydrogel as well as to the previously published α-arbutin encapsulated in chitosan nanoparticles and dispersed in hydrogel form. This delineates the aforementioned nano-vesicular systems as effective and clinically superior delivery means for melasma management.

Antigenic analysis of the influenza B virus hemagglutinin protein

Influenza B viruses (IBVs) primarily infect humans and are a common cause of respiratory infections in humans. Here, to systematically analyze the antigenicity of the IBVs Hemagglutinin (HA) protein, 31 ​B/Victoria and 19 ​B/Yamagata representative circulating strains were selected from Global Initiative of Sharing All Influenza Data (GISAID), and pseudotyped viruses were constructed with the vesicular stomatitis virus system. Guinea pigs were immunized with three doses of vaccines (one dose of DNA vaccines following two doses of pseudotyped virus vaccines) of the seven IBV vaccine strains, and neutralizing antibodies against the pseudotyped viruses were tested. By comparing differences between various vaccine strains, we constructed several pseudotyped viruses that contained various mutations based on vaccine strain BV-21. The vaccine strains showed good neutralization levels against the epidemic virus strains of the same year, with neutralization titers ranging from 370 to 840, while the level of neutralization against viruses prevalent in previous years decreased 1–10-fold. Each of the high-frequency epidemic strains of B/Victoria and B/Yamagata not only induced high neutralizing titers, but also had broadly neutralizing effects against virus strains of different years, with neutralizing titers ranging from 1000 to 7200. R141G, D197 ​N, and R203K were identified as affecting the antigenicity of IBV. These mutation sites provide valuable references for the selection and design of a universal IBV vaccine strain in the future.

Phytovesicular Nanoconstructs For Advanced Delivery of Medicinal Metabolites: An In-Depth Review.

Phytochemicals, the bioactive compounds in plants, possess therapeutic benefits, such as antimicrobial, antioxidant, and pharmacological activities. However, their clinical use is often hindered by poor bioavailability and stability. Phytosome technology enhances the absorption and efficacy of these compounds by integrating vesicular systems like liposomes, niosomes, transfersomes, and ethosomes. Phytosomes offer diverse biological benefits, including cardiovascular protection through improved endothelial function and oxidative stress reduction. They enhance cognitive function and protect against neurodegenerative diseases in the nervous system, aid digestion and reduce inflammation in the gastrointestinal system, and provide hepatoprotective effects by enhancing liver detoxification and protection against toxins. In the genitourinary system, phytosomes improve renal function and exhibit anti-inflammatory properties. They also modulate the immune system by enhancing immune responses and reducing inflammation and oxidative stress. Additionally, phytosomes promote skin health by protecting against UV radiation and improving hydration and elasticity. Recent patented phytosome technologies have led to innovative formulations that improve the stability, bioavailability, and therapeutic efficacy of phytochemicals, although commercialization challenges like manufacturing scalability and regulatory hurdles remain. Secondary metabolites from natural products are classified into primary and secondary metabolites, with a significant focus on terpenoids, phenolic compounds, and nitrogen-containing compounds. These metabolites have notable biological activities: antimicrobial, antioxidant, antibiotic, antiviral, anti-inflammatory, and anticancer effects. In summary, this review amalgamates the latest advancements in phytosome technology and secondary metabolite research, presenting a holistic view of their potential to advance therapeutic interventions and contribute to the ever-evolving landscape of natural product-based medicine.

Beyond Skin Deep: Phospholipid-Based Nanovesicles as Game-Changers in Transdermal Drug Delivery.

Transdermal administration techniques have gained popularity due to their advantages over oral and parenteral methods. Noninvasive, self-administered delivery devices improve patient compliance and control drug release. Transdermal delivery devices struggle with the skin's barrier function. Molecules over 500 Dalton (Da) and ionized compounds don't permeate through the skin. Drug encapsulation in phospholipid-based vesicular systems is the most effective skin delivery technique. Vesicular carriers include bi-layered liposomes, ultra-deformable liposomes, ethanolic liposomes, transethosomes, and invasomes. These technologies enhance skin drug permeation by increasing formula solubilization, partitioning into the skin, and fluidizing the lipid barrier. Phospholipid-based delivery systems are safe and efficient, making them a promising pharmaceutical and cosmeceutical drug delivery technique. Still, making delivery systems requires knowledge about the physicochemical properties of the drug and carrier, manufacturing and process variables, skin delivery mechanisms, technological advances, constraints, and regulatory requirements. Consequently, this review covers recent research achievements addressing the mentioned concerns.

Novel Vesicular Bilosomal Delivery Systems for Dermal/Transdermal Applications.

The application of therapeutically active molecules through the dermal/transdermal route into the skin has evolved as an attractive formulation strategy in comparison to oral delivery systems for the treatment of various disease conditions. However, the delivery of drugs across the skin is limited due to poor permeability. Dermal/transdermal delivery is associated with ease of accessibility, enhanced safety, better patient compliance, and reduced variability in plasma drug concentrations. It has the ability to bypass the first-pass metabolism, which ultimately results in steady and sustained drug levels in the systemic circulation. Vesicular drug delivery systems, including bilosomes, have gained significant interest due to their colloidal nature, improved drug solubility, absorption, and bioavailability with prolonged circulation time for a large number of new drug molecules. Bilosomes are novel lipid vesicular nanocarriers comprising bile salts, such as deoxycholic acid, sodium cholate, deoxycholate, taurocholate, glycocholate or sorbitan tristearate. These bilosomes are associated with high flexibility, deformability, and elasticity attributed to their bile acid component. These carriers are advantageous in terms of improved skin permeation, increased dermal and epidermal drug concentration, and enhanced local action with reduced systemic absorption of the drug, resulting in reduced side effects. The present article provides a comprehensive overview of the biopharmaceutical aspects of dermal/transdermal bilosome delivery systems, their composition, formulation techniques, characterization methods, and applications.

Innovative approaches in characterizing and developing methods for lipoidal vesicular drug delivery systems

Lipoidal vesicular systems, including liposomes, ethosomes, and transferosomes, represent a significant advancement in targeted drug delivery, offering enhanced bioavailability, controlled release, and specific targeting capabilities. This review discusses the types of lipoidal vesicular systems, their methods of characterization, method development, applications, advantages, challenges, and future perspectives. These systems have shown immense potential in diverse therapeutic areas, including cancer therapy, infectious diseases, gene therapy, and transdermal drug delivery. Despite the challenges in stability, scalability, and targeting, ongoing research and technological advancements promise to expand their applications and improve therapeutic outcomes.

Assessment of Brazil's vesicular syndrome surveillance system: Profile of notifications and performance of the official veterinary service

Foot-and-mouth disease (FMD) is an ailment that causes serious damage to the productive chain, and its control through vaccination is of utmost importance for its eradication. Brazil initiated the National Foot-and-Mouth Disease Surveillance Program (PNEFA) with the aim of making the country FMD-free by 2026. As part of the program, notifications of vesicular lesions became mandatory for the Official Veterinary Service (OVS), which is responsible for verifying them. Due to its size, border areas with countries that do not have FMD-free status pose a risk to Brazil and require greater attention. This study described the profile of notifications of suspected outbreaks of vesicular syndrome in Brazil and analyzed the performance of the surveillance system. The results showed 7134 registered notifications of suspected vesicular syndrome outbreaks from 2018 to 2022, with 2022 having the highest number (n = 2343 or 32.85 %). The species that generated the most notifications were swine (90.99 %), cattle and buffaloes (7.54 %), goats and sheep (1.44 %), and others (0.03 %). The sources of notification were "Veterinary medicine professionals" (61.82 %), "Owners or employees" (13.66 %), "Third parties" (8.90 %), "OVS" (7.20 %), and "others" (2.66 %). 41.69 % of notifications originated from non-border municipalities, and 58.32 % from border areas. Only the state of Paraná account for 51.73 % of the total notifications. This state also accounted for 66.70 % of the 32.47 % of notifications with a final diagnosis of "absence of clinically compatible signs or susceptible animals", indicating a certain lack of knowledge in the area, leading to unnecessary notifications and system overload. The performance of the OVS was evaluated based on the service response time from notification registration trough Logistic and Negative binomial regressions. A total of 27.83 % of notifications did not meet the Brazilian legally specified time, and the zone related to the state of Parana needs improvements in performance. The presence and peaks of Senecavirus A cases may have influenced an increased number of swine notifications and led to a decrease in OVS response time. The results demonstrate better performance of surveillance in border areas. Given the vast territory of Brazil, it is not expected that 100 % of responses occur within the legal timeframe, however, the performance of the surveillance system proved to be adequate, with 86 % complied to the legislation. The performance indicators could be used as a monitoring tool, along with indicators to demonstrate system overload. Continued education actions are crucial for strengthening PNEFA.

Exploring the Properties of Unilamellar Vesicle Bilayers Formed by Ionic Liquid Surfactants for Future Applications in Nanomedicine.

Two ionic liquids (ILs) with amphiphilic properties composed of 1-butyl-3-methylimidazolium dioctylsulfosuccinate (bmim-AOT) and 1-hexyl-3-methylimidazolium dioctylsulfosuccinate (hmim-AOT) form unilamellar vesicles spontaneously simply by dissolving the IL-like surfactant in water. These novel vesicles were characterized using two different and highly sensitive fluorescent probes: 6-propionyl-2-(dimethylaminonaphthalene) (PRODAN) and trans-4-[4-(dimethylamino)-styryl]-1-methylpyridinium iodide (HC). These fluorescent probes provide information about the physicochemical properties of the bilayer, such as micropolarity, microviscosity, and electron-donor capacity. In addition, the biocompatibility of these vesicles with the blood medium was evaluated, and their toxicity was determined using Dictyostelium discoideum amoebas. First, using PRODAN and HC, it was found that the bilayer composition and the chemical structure of the ions at the interface produced differences between both amphiphiles, making the vesicles different. Thus, the bilayer of hmim-AOT vesicles is less polar, more rigid, and has a lower electron-donor capacity than those made by bmim-AOT. Finally, the results obtained from the hemolysis studies and the growth behavior of unicellular amoebas, particularly utilizing the D. discoideum assay, showed that both vesicular systems do not produce toxic effects up to a concentration of 0.02 mg/mL. This elegant assay, devoid of animal usage, highlights the potential of these newly organized systems for the delivery of drugs and bioactive molecules of different polarities.