One of the difficulties of artificial intelligence is to ensure that model decisions are fair and free of bias. In research, datasets, metrics, techniques, and tools are applied to detect and ...mitigate algorithmic unfairness and bias. This study examines the current knowledge on bias and unfairness in machine learning models. The systematic review followed the PRISMA guidelines and is registered on OSF plataform. The search was carried out between 2021 and early 2022 in the Scopus, IEEE Xplore, Web of Science, and Google Scholar knowledge bases and found 128 articles published between 2017 and 2022, of which 45 were chosen based on search string optimization and inclusion and exclusion criteria. We discovered that the majority of retrieved works focus on bias and unfairness identification and mitigation techniques, offering tools, statistical approaches, important metrics, and datasets typically used for bias experiments. In terms of the primary forms of bias, data, algorithm, and user interaction were addressed in connection to the preprocessing, in-processing, and postprocessing mitigation methods. The use of Equalized Odds, Opportunity Equality, and Demographic Parity as primary fairness metrics emphasizes the crucial role of sensitive attributes in mitigating bias. The 25 datasets chosen span a wide range of areas, including criminal justice image enhancement, finance, education, product pricing, and health, with the majority including sensitive attributes. In terms of tools, Aequitas is the most often referenced, yet many of the tools were not employed in empirical experiments. A limitation of current research is the lack of multiclass and multimetric studies, which are found in just a few works and constrain the investigation to binary-focused method. Furthermore, the results indicate that different fairness metrics do not present uniform results for a given use case, and that more research with varied model architectures is necessary to standardize which ones are more appropriate for a given context. We also observed that all research addressed the transparency of the algorithm, or its capacity to explain how decisions are taken.
DC. is a plant species from the Asteraceae family that is endemic to Brazil. Despite the great importance of
genus, no study has been carried out regarding either the phytochemical composition of
or ...the evaluation of its larvicidal potential. Considering the intrinsic immiscibility of essential oils, this study shows larvicidal nanoemulsions containing the
phytochemically characterized essential oil and its main constituent against
. The major compound found was d-limonene (25.7%). The essential oil inhibited the acetylcholinesterase, one of the main targets of insecticides. The required hydrophile-lipophile balance of both nanoemulsions was 15.0. The mean droplet sizes were around 90.0 nm, and no major alterations were observed after 24 h of preparation for both formulations. After 48 h of treatment, the estimated LC
values were 118.94 μg mL
and 81.19 μg mL
for
essential oil and d-limonene nanoemulsions, respectively. Morphological alterations evidenced by scanning electron micrography were observed on the larvae treated with the d-limonene nanoemulsion. This paper demonstrated a simple and ecofriendly method for obtaining
essential oil and d-limonene aqueous nanoemulsions by a non-heating and solvent-free method, as promising alternatives for
control.
The role of oxidative stress in schizophrenia has been demonstrated, particularly in subjects with treatment-resistant schizophrenia (TRS). In such patients, the decreased levels of antioxidants in ...conjunction with the increased generation of reactive oxygen species in the brain exposes the neurons to a higher risk of damage.
We evaluated the association of deletion polymorphisms of two genes of the antioxidant Glutathione S-Transferase family, GSTT1 and GSTM1, with susceptibility to TRS. A total of 54 TRS patients (mean age 38.7 years) and 78 healthy control subjects (mean age 39.0 years) were enrolled in this study. The subjects were matched by sex, age, and smoking and alcohol consumption habits. In the case group, the frequencies of GSTT1-null and GSTM1-null genotypes were 24.1 and 51.9%, respectively, whereas for the control group, the frequencies were 12.8 and 46.2%, respectively. Analysis performed with respect to the risk of developing TRS associated with the GSTT1 and GSTM1 deletion polymorphisms, resulted in odds ratio (OR) values of 2.1 and 1.2, respectively. However, the association was not found to be significant (p = 0.1229 and p = 0.5916, respectively). The analysis performed with respect to the combined genotypes of GSTT1 and GSTM1 revealed that the double-null genotype confers a 4.6-fold increased risk of developing TRS (p = 0.0412).
The results of the present study indicate that a combination of GST deficiencies may play a role in enhanced susceptibility to TRS, and the present genotype of one of these genes may buffer the deficiency caused by the lack (null genotype) of the other. The results suggest that combined deletion polymorphisms of GSTT1 and GSTM1 can have implications in the prediction of the clinical course of the disease.
Pterodon emarginatus Vogel is a Brazilian species that belongs to the family Fabaceae, popularly known as sucupira. Its oil has several biological activities, including potent larvicidal property ...against Aedes aegypti. This insect is the vector of dengue, a tropical disease that has been considered a critical health problem in developing countries, such as Brazil. Most of dengue control methods involve larvicidal agents suspended or diluted in water and making active lipophilic natural products available is therefore considered a technological challenge. In this context, nanoemulsions appear as viable alternatives to solve this major problem. The present study describes the development of a novel nanoemulsion with larvicidal activity against A. aegypti along with the required Hydrophile Lipophile Balance determination of this oil. It was suggested that the mechanism of action might involve reversible inhibition of acetylcholinesterase and our results also suggest that the P. emarginatus nanoemulsion is not toxic for mammals. Thus, it contributes significantly to alternative integrative practices of dengue control, as well as to develop sucupira based nanoproducts for application in aqueous media.
•Annatto is an industrial food colorant.•Its seeds extract has low water solubility.•Nanodispersions preparation often use organic solvents.•A low-energy and solvent-free method was used in this ...study.•The present annatto nanoemulsions is a green-product.
The seeds of Bixa orellana L. is widely used in food industry as a natural colorant. A major technological challenge for its utilization on aqueous food products is the low water solubility. Therefore, the present study aimed to obtain aqueous nanodispersions using this natural raw material by using a simple organic solvent-free and low energy method. Bixin and geranylgeraniol were found on the extract. The nanodispersions were prepared by addition of water on a mixture of extract and surfactant (s). The effect of the surfactants and dilution on the nanodispersions were also evaluated. Best results were achieved using polysorbate 80/sorbitan monooleate (HLB 13) (diluted in water, 1:10). The results shows the potential of this ecofriendly approach, in contrast to common methods that make use of potentially toxic organic solvents and high input of energy, which elevate the costs for further industrialization.
Andiroba (Carapa guianensis) seeds are the source of an oil with a wide range of biological activities and ethnopharmacological uses. However, few studies have devoted attention to innovative ...formulations, including nanoemulsions. The present study aimed to obtain a colloidal system with the andiroba oil using a low-energy and organic-solvent-free method. Moreover, the preliminary residual larvicidal activity of the nanoemulsion against Aedes aegypti was evaluated. Oleic and palmitic acids were the major fatty acids, in addition to the phytosterol β-sitosterol and limonoids (tetranortriterpenoids). The required hydrophile-lipophile was around 11.0 and the optimal nanoemulsion was obtained using polysorbate 85. The particle size distribution suggested the presence of small droplets (mean diameter around 150 nm) and low polydispersity index (around 0.150). The effect of temperature on particle size distribution revealed that no major droplet size increase occurred. The preliminary residual larvicidal assay suggested that the mortality increased as a function of time. The present study allowed achievement of a potential bioactive oil in water nanoemulsion that may be a promising controlled release system. Moreover, the ecofriendly approach involved in the preparation associated with the great bioactive potential of C. guianensis makes this nanoemulsion very promising for valorization of this Amazon raw material.
Cassia grandis and Bixa orellana are important plant species with folk use and great potential for phytopharmaceuticals. Nanodispersions are disperse systems of insoluble or immiscible substances in ...a liquid medium that may be prepared with or without coating polymers. To our knowledge, no studies were carried in order to achieve coating-polymer free nanoformulations using B. orellana extract or any C. grandis-based nanoformulations. Thus, on the present study we aimed to develop C. grandis nanoformulations using three different coating polymers (Eudragit® L 100 55, PEG 4000 and Kollicoat®), while B. orellana nanodispersions were obtained using different surfactants (polysorbate 80, polysorbate 20, polyethylene glycol 400 monooleate, polyethylene glycol 600 monooleate, polyethylene glycol 400 dioleate and polyethylene glycol 600 dioleate) as coating polymer-free nanoformulations. Characterization of nanoformulations was performed by different parameters, including particle size, polydispersity index and zeta-potential. Our results suggested that some optimal nanoformulations were obtained for both plant species. Moreover, possible stable behavior was observed during storage period for C. grandis (30 days) and B. orellana (21 days). On this context, the present study contributes to nanobiotechnology development of phytopharmaceuticals, allowing achievement of novel nano-delivery systems with two important folk medicinal plant extracts and making them potential products for innovative phytopharmaceuticals.
Preparation of nanoformulations using natural products as bioactive substances is considered very promising for innovative larvicidal agents. On this context, oil in water nanoemulsions develop a ...main role, since they satisfactorily disperse poor-water soluble substances, such as herbal oils, in aqueous media. Pterodon emarginatus, popularly known as sucupira, has a promising bioactive oleoresin. However, to our knowledge, no previous studies were carried out to evaluate its potential against Culex quinquefasciatus, the main vector of the tropical neglected disease called lymphatic filariasis or elephantiasis. Thus, we aimed to investigate influence of different pairs of surfactants in nanoemulsion formation and investigate if a sucupira oleoresin-based nanoemulsion has promising larvicidal activity against this C. quinquefasciatus. We also evaluated morphological alteration, possible mechanism of insecticidal action and ecotoxicity of the nanoemulsion against a non-target organism.
Among the different pairs of surfactants that were tested, nanoemulsions obtained with polysorbate 80/sorbitan monooleate and polysorbate 80/sorbitan trioleate presented smallest mean droplet size just afterwards preparation, respectively 151.0 ± 2.252 and 160.7 ± 1.493 nm. They presented high negative zeta potential values, low polydispersity index (<0.300) and did not present great alteration in mean droplet size and polydispersity index after 1 day of preparation. Overall, nanoemulsion prepared with polysorbate 80/sorbitan monooleate was considered more stable and was chosen for biological assays. It presented low LC
value against larvae (34.75; 7.31-51.86 mg/L) after 48 h of treatment and some morphological alteration was observed. The nanoemulsion did not inhibit acetylcholinesterase of C. quinquefasciatus larvae. It was not toxic to green algae Chlorella vulgaris at low concentration (25 mg/L).
Our results suggest that optimal nanoemulsions may be prepared with different surfactants using a low cost and low energy simple method. Moreover, this prototype proved to be effective against C. quinquefasciatus, being considered an ecofriendly novel nanoproduct that can be useful in integrated control programs of vector control.
Development of Quercetin Based Nanodispersions Lefevre, Lauren; Ferreira, Adriana M; Vilhena, Jessica C E ...
Current topics in medicinal chemistry,
07/2016, Volume:
16, Issue:
18
Journal Article
Peer reviewed
Polyphenols are a large group of structurally diverse natural products, including flavonoids. One of the most bioactive compounds of this class is the flavonol quercetin, a recognized antioxidant. ...Despite several studies were carried out aiming to develop nanoformulations with secondary metabolites, to our knowledge, quercetin was not used as raw material for nanodispersion production without coating polymers. This type of nanosize formulation is often prepared using organic solvents and quercetin nanodispersions were prepared by emulsification evaporation technique, using 1(6).2(2) experimental factorial design, ("surfactant type" evaluated at 6 levels, "surfactant amount" and "stirring speed" evaluated at 2 levels). Variance analysis, after one day of nanodispersions preparation, revealed that only the surfactant type was statistically significant on particle size, while none of factors presented statistically significant effect on polydispersity index. Variance analysis after seven days of nanodispersions preparation revealed that either surfactant type and surfactant amount presented significant effect on particle size, while only surfactant type influenced polydispersity index. Some nanodispersions presented small diameter and narrow size distribution, suggesting potential stability of these systems. Special attention was given to nanodispersion prepared with 3 % (w/w) of polyethylene glycol 400 monooleate (expressed as function of surfactant concentration at aqueous phase). It presented mean droplet size of 129.4 ± 0.5 nm and polydispersity index of 0.173 ± 0.018, after 7 days of preparation. Low polydispersity index indicates a high homogeneity concerning particle size distribution and suggests stability of the system. Moreover, absence of coating polymers and utilization of a low energy method would be an advantage in terms of reducing costs for industrial application, without any nanosize impairment.
Mosquitoes can be vectors of pathogens and transmit diseases to both animals and humans. Species of the genus Culex are part of the cycle of neglected diseases, especially Culex quinquefasciatus, ...which is an anthropophilic vector of lymphatic filariasis. Natural products can be an alternative to synthetic insecticides for vector control; however, the main issue is the poor water availability of some compounds from plant origin. In this context, nanoemulsions are kinetic stable delivery systems of great interest for lipophilic substances. The objective of this study was to investigate the larvicidal activity of the Hyptis suaveolens essential oil nanoemulsion on Cx. quinquefasciatus. The essential oil showed a predominance of monoterpenes with retention time (RT) lower than 15 min. The average size diameter of the emulsions (sorbitan monooleate/polysorbate 20) was ≤ 200 nm. The nanoemulsion showed high larvicidal activity in concentrations of 250 and 125 ppm. CL50 values were 102.41 (77.5253−149.14) ppm and 70.8105 (44.5282−109.811) ppm after 24 and 48 h, respectively. The mortality rate in the surfactant control was lower than 9%. Scanning micrograph images showed changes in the larvae’s integument. This study achieved an active nanoemulsion on Cx. quinquefasciatus through a low-energy-input technique and without using potentially toxic organic solvents. Therefore, it expands the scope of possible applications of H. suaveolens essential oil in the production of high-added-value nanosystems for tropical disease vector control.
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