Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The development of high-performance nanocatalysts depends on generating stable and active surface sites at the atomic scale by systematically controlling the size, shape, and chemical composition of metals and metal oxides at the nanoscale. In this work, the synthesis and application of nanomaterials based mainly on alumina (Al2O3), Titania (TiO2), and some others of minor use, such as cerium oxide (CeO2), are mentioned. Furthermore, their morphological and textural characteristics and crystallographic phases obtained are briefly described. The importance of the synthesis methods in the morphology and structure of the nanoparticles and how this affects the catalytic activity of the supports and catalysts prepared with them is highlighted

In the early history of graphene, graphene oxide represented only an intermediate step in the methodology for obtaining graphene sheets. However, subsequent results of the investigation of this material showed that graphene oxide exhibits a structure with defects and functional groups that give it unique properties. Given the versatility of its surface, different functionalization routes have been proposed that have resulted in obtaining a wide variety of hybrid materials. In this work, we present the obtaining and characterization of three functionalized materials based on graphene oxide sheets decorated with nanoparticles of silver, titanium dioxide, and hydroxyapatite. These nanostructures were characterized by X-ray diffraction, Raman spectroscopy, and transmission electron microscopy. In particular, the improvement in the thermal properties of oxidized graphene-silver nanoparticles was studied through thermogravimetric analysis (TGA), the improvement of Raman signals through the chemical mechanism of SERS in the material decorated with titanium dioxide, and an MTT cell viability assay, in which it was observed that the oxidized graphene decorated with hydroxyapatite obtained using urea did not present cytotoxicity.

Nanotechnology and artificial intelligence are two scientific fields that individually have promoted a scientific and technological revolution across the globe. While nanotechnology enables the manipulation of matter at nanometric scales to develop applications and technologies with unique properties, artificial intelligence emerges as a set of effective techniques to potentiate computer systems that perform tasks of classification, optimization, prediction, and pattern recognition, imitating the capabilities of the human being. The intersection between both fields constitutes a multidisciplinary and modern research area that promises to boost a new generation of technologies and address critical challenges that contribute to the advancement of science. This work presents a general review of the efforts reported in the literature where the self-learning attributes of some artificial intelligence algorithms are exploited in the context of nanotechnology. Additionally, future trends and perspectives where these fields converge are discussed.

Candidiasis is a disease caused by different Candida species, with C. albicans being the most common in clinical isolates worldwide. This disease is a problem for the health sector, due to the multiresistance that some Candida species present to the antifungals traditionally used. C. glabrata and C. auris are two species frequently reported as resistant to azoles, echinocandins and polyenes. Therefore, the search for new antifungals is a priority. Nanotechnology offers new alternatives, such as the use of metallic nanoparticles (NPs). In particular, silver and copper NPs have been reported as efficient inhibition agents against C. albicans. This paper presents the most relevant studies that have evaluated the effect of metallic NPs in Candida spp., as well as the most promising results.

Chitin is a linear polysaccharide produced by animal and fungal species. One of its sources is the fungus Aspergillus niger, which is culturable in industrial bioreactors. Chitin is a neutral biopolymer that modifies the electrical properties of composite materials. These are useful features in some electronic devices. This study aimed to carry out physicochemical characterizations of chitin films obtained from the above-mentioned fungus, using a chemical method enhanced with exposure to heat and shock waves, and to determine their electrical resistivity at high voltages (between 10 and 20 kV). Shock waves were used in this study because they are known to induce pores into cells and could promote alkali entry into the hypha, allowing better removal of residual cellular components. Chitin was neutralized, dried, and films were produced. Residual protein values were quantified by bicinchoninic acid assay (BCA). The films obtained had low amounts of protein. The characterization of the specific morphotype extracted was done by FTIR and XRD. An especially designed circuit revealed significant variations of the resistivity as the voltage was varied. This behavior is typical of a non-linear varistor and, to the best of our knowledge, has not been reported for chitin.

Liposomes are biocompatible and biodegradable artificial vesicles with a two-compartment structure that can encapsulate both hydrophilic and lipophilic molecules. Liposomes have been extensively studied over the last twenty years, leading to the development of several promising technologies including Stealth® and DepoFoam® liposomes. Also targeted, physicochemical stimuli-responsive, and liposomal-based combined therapies have evolved. Liposomes are the first nanomedicines to reach the clinical use. Currently, up to 20 different liposomal technologies are commercially available, and approximately 18 liposomal formulations are in clinical trials. While most commercial liposomes are used to treat cancer, there are some liposomal developments that have shown promising results for treating other diseases. In this review, we present an overview of the basic concepts of liposomes, breakthroughs in liposomal-based nanoformulations in clinical trials and currently marketed liposomal technologies. Furthermore, using data science tools, we present a comprehensive analysis of current research in liposomes. Undoubtedly, liposomes will continue to be at the forefront of nanotechnologies applied for the benefit of human health.

Biosensing systems are powerful biotechnological tools which are widely applied in medical and environmental settings. Herein, we provide an overview of a recently developed optical biosensing system based on the quenching abilities of graphene oxide and fluorescent bioprobes. This biosensing platform has been demonstrated to be a fast, cost-effective and reliable nanophotonic technology. In particular, it has been exploited to detect relevant analytes in real matrixes, including prostate specific E. coli and COVID-19 antibodies. Besides, this technology enabled the detection of sialidase in clinical samples to determine bacterial vaginosis. This biosensing system has recently been used to determine relevant information on the kinetics of proteins involved in the biorecognition process, everything performed in real-time and in a single step.

Living organisms are made of self-assembled nanostructures. Therefore, the control of sizes, shapes, textures, or chemical functions during chemical synthesis, as managed by nanotechnology, leads to a myriad of possibilities in the field of biomedical applications. One of the main approaches in this area, also known as nanomedicine, is the production of biomimetic nanoparticles, which take profit from either natural products or bioinspired materials. Cell-cell communications are strongly dependent on molecular arrays displayed at the cell surface in the context of lipid bilayers. Therefore, the mimicry of such coatings has gained great interest during the last decades. Herein we summarize the rationale and the methodologies related to this approach, with a special focus on the delivery of drugs and vaccines. The challenges and opportunities in this area, along with some selected examples will be discussed as well.

The Raphidascarididae family is composed of nematodes that carry out their life cycle in environments using different intermediate or paratenic hosts, such as invertebrates, fish, waterfowl and mammals. The genera of this family can be subdivided into Raphidascaris Railliet & Henry, 1915, Ichthyascaris Wu, 1949 and Sprentascaris Petter & Cassone, 1984 and all can act as fish parasites. The objective of this work was to analyze host fish of the Loricariidae family of two species of zoonotic nematodes. The study was carried out in the municipality of Cruzeiro do Sul, Acre, Brazil. A total of 42 Sprentascaris mahnerti Petter & Cassone, 1984 were collected from three hosts of the Loricariidae family, 27 from Limatulichthys griseus Eigenmann, 1909, 10 from Spatuloricaria sp. Schultz, 1944 and 5 in Hypoptopoma steindachneri Boulenger, 1895. For Raphidascaris sp. Railliet & Henry, 1915 a total of 12 larvae were found in five species of Loricariidae, where the highest value was found in Spataculoricaria sp. Schultz, 1944. The present study showed that Raphidascaris sp. Railliet & Henry, 1915 parasitized a greater number of hosts than S. mahnerti Petter & Cassone, 1984, in which Spatuloricaria sp. Schultz, 1944 was the host with the highest number of infected specimens. S. mahnerti Petter & Cassone, 1984 showed the highest abundance of individuals, where the host with the highest number of infected specimens was L. griseus Eigenmann, 1909.

The phylum Nematoda is considered one of the most diverse groups in South America, as it is found in all habitats and is dynamic regarding the ecological characteristics of environments, this group becomes important for monitoring the state of ecosystems, thus making it of great importance. Its identification and occurrences in western Amazonia. Thus, the present study aims to present a list of fish nematodes in western Amazonia, as well as to describe their specific hosts. The study was carried out in the Alto Juruá region of the Western Amazon around the municipalities of Cruzeiro do Sul – Acre and Guajará – AM, Brazil. A total of 10,716 fish were collected, belonging to eight orders, 32 families and 216 species, with only 164 species showing nematodes. The species with the highest number of hosts were Procamallanus (S.) inopinatus Travassos et al., (1928), (67), Contracaecum sp. Railliet & Henry, (1912), (65) and Cosmoxynemoides aguirrei Travassos, (1948), (14). Since for the Western Amazon basin, 23 new hosts were found for P. (S) inopinatus, 27 for Contracaecum sp. and eight for C. aguirre. Thus, the present study reports a great diversity of nematodes parasitic on fish in western Amazonia, contributes to several new occurrences of these parasites and further strengthens the importance of studies of these helminths in this region.