In Vitro Cytotoxicity Screening as a Criterion for the Rational Selection of Tear Substitutes

A large number of artificial tears are currently available in the pharmaceutical market. Selecting the right drug for the patient remains a challenge for both the doctor and the patient. Comparing the cytotoxicity of artificial tears is one of the criteria for the rational selection of a drug that promotes maximum clinical efficacy and a higher safety profile. It is known that cells grown in vitro retain many metabolic features of the parent host tissues and at the same time lack tissue and organ interrelations and regulatory effects of the nervous and endocrine systems and have very limited compensatory capabilities. These features of cell cultures provide an opportunity to investigate the interaction of chemical agents directly with the cell itself, to identify changes in cellular and subcellular structures that can be masked in whole-organism settings. This study presents the results of assessing the cytotoxicity of tear substitutes, which demonstrate that these drugs can have a cytostatic effect in vitro and differ in their cytotoxic potential. In recent years, the problem of drug therapy of patients with dry eye syndrome has been attracting increasing attention of ophthalmologists, so screening the cytotoxicity of a wide range of tear substitutes using cell culture-based test systems can promote the rational selection of these drugs

Poultry compost in the composition of substrates for flower seedlings production

Se evaluaron sustratos formulados con distintas proporciones (20, 50 y 80%) de tres tipos de compost de guano de gallina (CGG1, CGG2, CGG3) mezclados con compost de corteza de pino y un sustrato comercial. Los diez tratamientos fueron usados para el cultivo de plantines de Impatiens walleriana y Salvia splendens. Se caracterizó física y químicamente cada sustrato, y sobre los plantines se evaluó sobrevivencia, masa seca y calcio, magnesio, potasio y sodio en la hoja. Los sustratos con 20% y 50% de los tres CGG tuvieron la mayor capacidad de retención de agua, y con 80%, la mayor porosidad de aire. Los sustratos con 50% y 80% presentaron los más altos valores de pH (≥6,6), potasio y sodio. Para las mismas proporciones, CGG2 y CGG3 presentaron valores de CE >1,1 dS cm-1. La mayor masa seca de los plantines se logró para el sustrato comercial, los sustratos con 20% de los tres CGG y con 50% de CGG1. Estos sustratos exhibieron en las hojas una mayor concentración de calcio y magnesio, y menor de potasio. Las mejores características de sustratos para el desarrollo de los plantines evaluados se lograron en los sustratos con 20% de los tres CGG y con 50% del compost CGG1.Substrates formulated with different proportions (20, 50 and 80%) of three types of poultry compost (CGG1, CGG2, CGG3) mixed with pine bark compost and commercial substrate were evaluated. The ten treatments were used to cultivate seedlings of walleriana Impatiens and Salvia splendens. Each substrate was characterised physically and chemically, and the survival, dry mass and calcium, magnesium, potassium and sodium in the leaf were evaluated in seedlings. Substrates with 20% and 50% among the three CGG presented the highest water retention capacity and, with 80% the highest air porosity. The substrates with 50% and 80% showed the highest values of pH (≥ 6.6), potassium and sodium. For the same proportions, CGG2 and CGG3 presented CE values > 1.1 dS cm-1. The highest dry weight of the seedlings was achieved with the commercial substrate, the substrates with 20% of the three CGG and with 50% of CGG1. These substrates showed a higher concentration of calcium and magnesium, and a lower concentration of potassium in the leaves. The best characteristics of substrates for the development of the seedlings tested were achieved in the substrates with 20% of the three CGG and with 50% of compost CGG1.Fil: Bárbaro, L. A.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; ArgentinaFil: Karlanian, M. A.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Recursos Naturales. Instituto de Floricultura; ArgentinaFil: Rizzo, P. F.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Riera, N. I.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Della Torre, V.. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; ArgentinaFil: Beltrán, M.. Instituto Nacional de Tecnologia Agropecuaria. Centro Nacional de Inv. Agropecuarias. Centro de Invest.de Recursos Naturales. Instituto de Suelos; ArgentinaFil: Crespo, Diana. Instituto Nacional de Tecnología Agropecuaria. Centro Nacional de Investigaciones Agropecuarias. Centro de Investigación de Ciencias Veterinarias y Agronómicas. Instituto de Microbiología y Zoología Agrícola; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Observation of a narrow baryon resonance with positive strangeness formed in K+K^+Xe collisions

The charge-exchange reaction K^+ Xe --> K^0 p Xe' is investigated using the data of the DIANA experiment. The distribution of the pK^0 effective mass shows a prominent enhancement near 1538 MeV formed by \sim 80 events above the background, whose width is consistent with being entirely due to the experimental resolution. Under the selections based on a simulation of K^+Xe collisions, the statistical significance of the signal reaches 5.5\sigma. We interpret this observation as strong evidence for formation of a pentaquark baryon with positive strangeness, \Theta^+(uudd\bar{s}), in the charge-exchange reaction K^+ n --> K^0 p on a bound neutron. The mass of the \Theta^+ baryon is measured as m(\Theta^+) = 1538+-2 MeV. Using the ratio between the numbers of resonant and non-resonant charge-exchange events in the peak region, the intrinsic width of this baryon resonance is determined as \Gamma(\Theta^+) = 0.34+-0.10 MeV.Comment: 19 pages, 8 figure

Body Weight, Oocyte Elimination and Blood Profile of Rabbit After Challenge Test Using Eimeria Stiedai

The objective of the research was to investigate body weight, oocyte elimination and blood profile of rabbits infected with various doses of Eimeria stiedai isolates. The observed rabbits' blood profile included erythrocyte, hemoglobin, hematocrit, leucocyte, thrombocyte, total protein plasma (TPP) and fibrinogen. Twenty-five male New Zealand White rabbits aged 3 months and weighed approximately 2 kg were provided with pellet and boiled drinking water and Eimeria stiedai isolates. The experiment used Completely Randomized Design to analyze 5 treatments with five replicates. The examined variables included D0: Infection 0 (control of infection without challenge test), D1: Infection 101 with challenge test 103, D2: infection 102 with challenge test 103, D3: infection 103 with challenge test 103, D4: infection 0 with challenge test 103 (control of infection). Data were subject to analysis of variance followed by Honestly Significant Difference Test (HSD). Analysis of Variance result showed that there was no significant difference on body weight, oocyte elimination and blood profile including erythrocyte, hemoglobin, hematocrit, leucocyte, thrombocyte, and fibrinogen. However, total protein plasma (TTP) was significantly different at 5% HSD. It can be concluded that challenge test with Eimeria stiedai has not been used as an alternative in increasing rabbits' body immune against coccidiosis infection

Mapping the G-structures and supersymmetric vacua of five-dimensional N=4 supergravity

We classify the supersymmetric vacua of N=4, d=5 supergravity in terms of G-structures. We identify three classes of solutions: with R^3, SU(2) and generic SO(4) structure. Using the Killing spinor equations, we fully characterize the first two classes and partially solve the latter. With the N=4 graviton multiplet decomposed in terms of N=2 multiplets: the graviton, vector and gravitino multiplets, we obtain new supersymmetric solutions corresponding to turning on fields in the gravitino multiplet. These vacua are described in terms of an SO(5) vector sigma-model coupled with gravity, in three or four dimensions. A new feature of these N=4 vacua, which is not seen from an N=2 point of view, is the possibility for preserving more exotic fractions of supersymmetry. We give a few concrete examples of these new supersymmetric (albeit singular) solutions. Additionally, we show how by truncating the N=4, d=5 set of fields to minimal supergravity coupled with one vector multiplet we recover the known two-charge solutions.Comment: 31 pages, late

Hyaluronan functionalized pH-responsive calcium carbonate nanoparticles for local treatment of breast cancer

[Excerpt] Introduction: Current radio- and chemotherapies are not efficient and many tumors remain resistant to conventional cancer treatments. Specific properties and signaling molecules from tumor microenvironment (TME) have been explored to increase treatment efficacy. An example is the acidic pH of the TME that has been explored to develop stimuli responsive release systems. Herein, we obtained biocompatible calcium carbonate (CaCO3) nanoparticles that are stable at neutral pH but dissolve at acidic conditions and evaluated their potential as a drug carrier for local cancer treatment. METHODS: CaCO3 nanoparticles were produced by co-precipitation of calcium chloride (CaCl2) and sodium carbonate (Na2CO3) in the presence of ethylene glycol [1]. Rhodamine was encapsulated as a model drug. The morphology and diameter of the nanoparticles were determined by scanning electron microscopy and dynamic laser scattering. The particles were coated by layer-by-layer (LbL) assembly of poly-L-lysine and hyaluronic acid (HA). The release was studied in phosphate buffered saline at pH 6.3 and 7.4. Cultures of two breast cancer cell lines (MDA-MB-231 and SK-BR-3) and a healthy epithelial cell line MCF10A (control) were observed under confocal laser scanning microscopy to assess particles internalization and their effect on cell viability (live/dead staining) and metabolic activity (Alamar Blue). [...]Portuguese Fundação para a Ciência e Tecnologia (FCT, grants CEECIND/02842/2017, SFRH/BPD/85790/2012; project PTDC/CTM-REF/0022/2020)

Layer-by-layer coated calcium carbonate nanoparticles for targeting breast cancer cells

Breast cancer is resistant to conventional treatments due to the specific tumour microenvironment, the associated acidic pH and the overexpression of receptors that enhance cells tumorigenicity. Herein, we optimized the synthesis of acidic resorbable calcium carbonate (CaCO3) nanoparticles and the encapsulation of a low molecular weight model molecule (Rhodamine). The addition of ethylene glycol during the synthetic process resulted in a particle size decrease: we obtained homogeneous CaCO3 particles with an average size of 564 nm. Their negative charge enabled the assembly of layer-by-layer (LbL) coatings with surface-exposed hyaluronic acid (HA), a ligand of tumour-associated receptor CD44. The coating decreased Rhodamine release by two-fold compared to uncoated nanoparticles. We demonstrated the effect of nanoparticles on two breast cancer cell lines with different aggressiveness â SK-BR-3 and the more aggressive MDA-MB-231 â and compared them with the normal breast cell line MCF10A. CaCO3 nanoparticles (coated and uncoated) significantly decreased the metabolic activity of the breast cancer cells. The interactions between LbL-coated nanoparticles and cells depended on HA expression on the cell surface: more particles were observed on the surface of MDA-MB-231 cells, which had the thickest endogenous HA coating. We concluded that CaCO3 nanoparticles are potential candidates to carry low molecular weight chemotherapeutics and deliver them to aggressive breast cancer sites with an HA-abundant pericellular matrix. This work was supported by the Fundação para a Ciência e Tecnologia (project OncoNeoTreat, grant number PTDC/CTM-REF/0022/2020, co-financed by FCT – OE component); and the European program FEDER/FEEI. R.R.C. acknowledges FCT for support through grants 2022.00764.CEECIND and CEECIND/02842/2017. D.S.C. thanks FCT for the grant SFRH/BPD/85790/2012. Parts of Fig. A.1 were drawn by using pictures from Servier Medical Art. Servier Medical Art by Servier is licensed under a Creative Commons Attribution 3.0 Unported License (https://creativecommons.org/licenses/by/3.0/)

Ontogenetic Development of Neurophysiological Mechanisms Underlying Language Processing

During the last 20 years, new data on the neurophysiological mechanisms underlying different types of cognitive activity, especially speech and its ontogenetic formation, were obtained in the Laboratory of Children’s Neurophysiology headed by Prof. M.N. Tsitseroshin. Using the analysis of the spatial-temporal structure of regional interactions of cortical bioelectric potentials (so-called functional connectivity), we investigated how specific language levels, such as phonology, grammar, and semantics, are represented in the brain. The data obtained in children vs. adults indicate that the speech perception and production require joint and extremely coordinated activities of both hemispheres, along with the obligatory and differentiated involvement of “classic” speech centers in the left hemisphere, especially Wernicke’s area. Another line of our research is to explore the differences, which arise during verbal processing in adults and children with impaired vs. non-impaired speech, particularly with alalia, dysarthria and stuttering, using behavioral and EEG data. Our data obtained in children vs. adults allow assessing the degree of maturity in the organization of the central processes of maintaining the studied types of verbal activity in children of different ages. These data allow expanding modern concepts about the brain mechanisms of verbal activity in children in the norm and pathology