Unveiling novel targets in melanoma under melanogenesis stimulation and photodynamic therapy by redox proteomics.

Melanogenesis-stimulated B16-F10 cells enter in a quiescent state, present inhibited mitochondrial respiration and increased reactive oxygen species levels. These alterations suggest that these cells may be under redox signaling, allowing tumor survival. The aim of this study was to evaluate redox-modified proteins in B16-F10 cells after melanogenesis stimulation and rose bengal-photodynamic therapy (RB-PDT). A redox proteomics label-free approach based on the biotin switch assay technique with biotin-HPDP and N-ethylmaleimide was used to assess the thiol-oxidized protein profile. Aconitase was oxidized at Cys-448 and Cys-451, citrate synthase was oxidized at Cys-202 and aspartate aminotransferase (Got2) was oxidized at Cys-272 and Cys-274, exclusively after melanogenesis stimulation. After RB-PDT, only guanine nucleotide-binding protein subunit beta-2-like 1 (Gnb2l1) was oxidized (Cys-168). In contrast, melanogenesis stimulation followed by RB-PDT led to the oxidation of different cysteines in Gnb2l1 (Cys-153 and Cys-249). Besides that, glyceraldehyde-3-phosphate dehydrogenase (Gapdh) presented oxidation at Cys-245, peptidyl-prolyl cis-trans isomerase A (Ppia) was oxidized at Cys-161 and 5,6-dihydroxyindole-2-carboxylic acid oxidase (Tyrp1) was oxidized at Cys-65, Cys-30, and Cys-336 after melanogenesis stimulation followed by RB-PDT. The redox alterations observed in murine melanoma cells and identification of possible target proteins are of great importance to further understand tumor resistance mechanisms.

Unveiling novel targets in melanoma under melanogenesis stimulation and photodynamic therapy by redox proteomics

Melanogenesis- stimulated B16-F10 cells enter in a quiescent state, present inhib-ited mitochondrial respiration and increased reactive oxygen species levels. Thesealterations suggest that these cells may be under redox signaling, allowing tumorsurvival. The aim of this study was to evaluate redox-modified proteins in B16-F10 cells after melanogenesis stimulation and rose bengal-photodynamic therapy(RB-PDT). A redox proteomics label-free approach based on the biotin switchassay technique with biotin-HPDP and N-ethylmaleimide was used to assess thethiol-oxidized protein profile. Aconitase was oxidized at Cys-448 and Cys-451,citrate synthase was oxidized at Cys-202 and aspartate aminotransferase (Got2)was oxidized at Cys-272 and Cys-274, exclusively after melanogenesis stimula-tion. After RB- PDT, only guanine nucleotide-binding protein subunit beta- 2- like1 (Gnb2l1) was oxidized (Cys-168). In contrast, melanogenesis stimulation fol-lowed by RB- PDT led to the oxidation of different cysteines in Gnb2l1 (Cys-153and Cys- 249). Besides that, glyceraldehyde-3-phosphate dehydrogenase (Gapdh)presented oxidation at Cys-245, peptidyl-prolyl cis-trans isomerase A (Ppia) wasoxidized at Cys-161 and 5,6-dihydroxyindole-2-carboxylic acid oxidase (Tyrp1)was oxidized at Cys-65, Cys-30, and Cys-336 after melanogenesis stimulation fol-lowed by RB-PDT. The redox alterations observed in murine melanoma cells andidentification of possible target proteins are of great importance to further under-stand tumor resistance mechanisms.

Biochemical and insecticidal efficacy of clove and basil essential oils and two photosensitizers and their combinations on Aphis gossypii glover (Hemiptera: Aphididae)

The present study investigates the insecticidal and biochemical effects of two essential oils (EOs) and two photosensitizers against cotton aphids in a laboratory setting. The EOs evaluated were clove (Syzygium aromaticum L.) and basil (Ocimum basilicum), while the photosensitizers were rose bengal and rhodamine B. The individual median lethal concentrations (LC50) revealed that clove was ~4.44 times more potent than basil, and rhodamine B was ~1.34 times more potent than rose bengal. The mortality rates increased using higher concentrations of the photosensitizers and prolonging exposure time to sunlight. The most effective combination against adult aphids was found to be a mixture of sub-lethal concentrations of clove and rhodamine B, resulting in a mortality rate of 92.31%. Conversely, the combination of basil and rose bengal exhibited the lowest efficacy with a mortality rate of 33.33%. Biochemical analyses indicate that Rhodamine B, basil, and the basil-rhodamine B mixture (mixture C) significantly reduced trehalase activity. However, the protease activity significantly increased in aphids treated with rose bengal, clove, and the clove-rose bengal mixtures (mixtures A and B). The lipase activity is notably decreased upon treatment with rhodamine B and clove. Glutathione S-transferase (GST) activity decreased in aphids treated with rose bengal and the basil-rhodamine B mixtures (mixtures C and D), suggesting that GST did not play a role in detoxifying these compounds, thereby explaining the susceptibility of A. gossypii. Overall, the combination of essential oils and photosensitizers has demonstrated a synergistic effect in controlling Aphis gossypii, offering great potential as an effective strategy for aphid management.

Self-Organization Dynamics of Collagen-like Peptides Crosslinking Is Driven by Rose-Bengal-Mediated Electrostatic Bridges.

The present work focuses on the computational study of the structural micro-organization of hydrogels based on collagen-like peptides (CLPs) in complex with Rose Bengal (RB). In previous studies, these hydrogels computationally and experimentally demonstrated that when RB was activated by green light, it could generate forms of stable crosslinked structures capable of regenerating biological tissues such as the skin and cornea. Here, we focus on the structural and atomic interactions of two collagen-like peptides (collagen-like peptide I (CLPI), and collagen-like peptide II, (CLPII)) in the presence and absence of RB, highlighting the acquired three-dimensional organization and going deep into the stabilization effect caused by the dye. Our results suggest that the dye could generate a ternary ground-state complex between collagen-like peptide fibers, specifically with positively charged amino acids (Lys in CLPI and Arg in CLPII), thus stabilizing ordered three-dimensional structures. The discoveries generated in this study provide the structural and atomic bases for the subsequent rational development of new synthetic peptides with improved characteristics for applications in the regeneration of biological tissues during photochemical tissue bonding therapies.

Visible light-catalyzed fluoroalkylation reactions of free aniline derivatives.

The electron-rich nature of aminoaromatic compounds and the electrophilic character of fluoroalkyl RF radicals allow for a special match in substitution reactions. We herein present visible light photocatalyzed fluoroalkylation reactions of aniline derivatives, with a study of the reaction mechanisms. The examples evaluated make use of different photocatalysts, such as polypyridyl complexes of Ir or Ru transition metals, organic dyes such as Rose Bengal, phthalocyanine-metal organocatalysts, or visible-light activated complexes. Different visible light sources that span from the blue region of the electromagnetic spectrum to low power red light irradiation sources deliver the excited photocatalysts that ensue into the production of fluoroalkyl RF radicals. In turn, many sources of RF radicals can be employed, such as fluoroalkyl halides, Togni's reagents, Umemoto's reagent, etc. All these protocol variants demonstrate the expansion of the methodology and the versatility of photocatalytic techniques applied to a special family of organic compounds such as aminoaromatic substrates, which has been studied by different groups. Contributions from our own laboratory will be given.

Antimicrobial activity of topical dyes used in clinical veterinary ophthalmology.

OBJECTIVE: To evaluate in vitro the antibacterial effects of fluorescein, rose bengal, and lissamine green topical ophthalmic dyes against selected Gram-positive and Gram-negative bacteria, and to evaluate whether preserved or preservative-free fluorescein solutions are able to inhibit or potentiate bacterial growth. PROCEDURES: Susceptibility testing was performed using the Kirby-Bauer disk diffusion method plated with clinical ocular isolates of Staphylococcus aureus, Staphylococcus pseudintermedius, Streptococcus spp., Escherichia coli, and Pseudomonas aeruginosa. Bacterial growth inhibition was evaluated 24 hours following the addition of commercially available fluorescein, rose bengal, and lissamine green sterile strips. Antimicrobial effectiveness testing was performed by inoculation of compounded 1% dye solutions, both with and without preservatives (fluorescein and lissamine contained thiomersal, and rose bengal contained nipagin and nepazol), with the five previously mentioned bacteria. Growth was evaluated at days 7, 14, and 28. RESULTS: All dyes showed antibacterial activity against Gram-positive organisms. Preservative-free compounded 1% fluorescein solution inhibited growth of Gram-positive organisms but not of Gram-negative organisms. Preservative-free rose bengal and lissamine green inhibited growth of both types of organisms. CONCLUSIONS: Preferably, ocular surface samples for antimicrobial culture should be taken prior to the administration of topical dyes, due to their potential antibacterial activity, particularly if undiluted strips are applied directly or commercial fluorescein solutions are used and not immediately rinsed. Ophthalmic dye solutions containing preservative are safe from bacterial growth for up to 28 days if properly handled and stored. The use of preservative-free fluorescein solutions should be avoided and preservative-free rose bengal and lissamine green should be handled carefully.

Binding of rose bengal to lysozyme modulates photooxidation and cross-linking reactions involving tyrosine and tryptophan.

This work examined the hypothesis that interactions of Rose Bengal (RB2-) with lysozyme (Lyso) might mediate type 1 photoreactions resulting in protein cross-linking even under conditions favoring 1O2 formation. UV-visible spectrophotometry, isothermal titration calorimetry (ITC), and docking analysis were employed to characterize RB2--Lyso interactions, while oxidation of Lyso was studied by SDS-PAGE gels, extent of amino acid consumption, and liquid chromatography (LC) with mass detection (employing tryptic peptides digested in H218O and H2O). Docking studies showed five interaction sites including the active site. Hydrophobic interactions induced a red shift of the visible spectrum of RB2- giving a Kd of 4.8 µM, while data from ITC studies, yielded a Kd of 0.68 µM as an average of the interactions with stoichiometry of 3.3 RB2- per Lyso. LC analysis showed a high consumption of readily-oxidized amino acids (His, Trp, Met and Tyr) located at different and diverse locations within the protein. This appears to reflect extensive damage on the protein probably mediated by a type 2 (1O2) mechanism. In contrast, docking and mass spectrometry analysis provided evidence for the generation of specific intra- (Tyr23-Tyr20) and inter-molecular (Tyr23-Trp62) Lyso cross-links, and Lyso dimer formation via radical-radical, type 1 mechanisms.

Efficient in vitro photodynamic inactivation using repetitive light energy density on Candida albicans and Trichophyton mentagrophytes.

BACKGROUND: We compared the effectiveness of a single irradiation vs repetitive irradiation of light, for in vitro photodynamic inactivation (PDI) of Candida albicans and Trichophyton mentagrophytes, by using methylene blue (MB) and rose bengal (RB) as photosensitizers (PS). METHODS: MB from 5 to 60 µM and RB from 0.5 to 10 µM, with energy densities from 10 to 60 J/cm2, were tested in C. albicans. We further optimize the PDI by reducing the light energy density and PS concentration for the single irradiation experiments by using repetitive doses (two and three times). MB was tested in C. albicans and T. mentagrophytes, and RB was tested in C. albicans. RESULTS: MB-PDI and RB-PDI in C. albicans significantly reduced the number of colony-forming units per milliliter (CFU/mL) when compared to the control groups. Using a single irradiation, over 99% growth inhibition of C. albicans was obtained with MB at 20 µM-60 J/cm2, and with RB at 1 µM-30 J/cm2 and 5 µM-10 J/cm2. With repetitive doses, similar results were obtained by reducing several times the light energy density and the PS concentration for C. albicans and T. mentagrophytes. CONCLUSIONS: The results showed that RB was more effective than MB for C. albicans inactivation. In addition, it is possible to significantly reduce the amount of PS and light energy density requirements by using repetitive irradiations in both genera tested. It makes the technique less invasive and could reduce the side effects in people extremely sensitive to the PS or the light.

Xanthene Dyes and Green LED for the Inactivation of Foodborne Pathogens in Planktonic and Biofilm States.

This study evaluated the rose bengal- and erythrosine-mediated photoinactivation against Salmonella Typhimurium and Staphylococcus aureus planktonic and sessile cells using green LED as a light source. The free-living or 2-day-old biofilm cells were treated with different concentrations of the photosensitizing agents and subjected to irradiation. Only 5 min photosensitization with rose bengal at 25 nmol L-1 and 75 µmol L-1 completely eliminated S. aureus and S. Typhimurium planktonic cells, respectively. Erythrosine at 500 nmol L-1 and 5 min of light exposure also reduced S. aureus planktonic cells to undetectable levels. Eradication of S. aureus biofilms was achieved when 500 µmol L-1 of erythrosine or 250 µmol L-1 of rose bengal was combined with 30 min of irradiation. Scanning electron microscopy allowed the observation of morphological changes in planktonic cells and disruption of the biofilm architecture after photodynamic treatment. The overall data demonstrate that rose bengal and erythrosine activated by green LED may be a targeted strategy for controlling foodborne pathogens in both planktonic and sessile states.

Rose Bengal incorporated to α-cyclodextrin microparticles for photodynamic therapy against the cariogenic microorganism Streptococcus mutans.

Rose Bengal@α-cyclodextrin (RB@α-CD) microparticles (µPs) were prepared and the RB inclusion in α-CD was experimentally demonstrated through infrared, UV-VIS absorption spectroscopy and cyclic voltammetry. The RB inclusion in α-CD was theoretically investigated using classical molecular mechanics calculations, the simulation results showing that RB can be included in both the narrow and wide apertures of the α-cyclodextrin ring with configurations exhibiting average binding energies of about 27 kcal mol-1. The prepared RB@α-CD microparticles were characterized through Scanning Electron Microscopy (SEM) and it was demonstrated that they are highly efficient in the photodynamic therapy against a Streptococcus mutans (the main bacteria of cariogenic dental plaque) suspension, as a concentration of RB@α-CD µPs 10 times smaller than the usual concentration of pure RB is still capable to produce significant antibacterial activity.

Survey of Brucella spp. and Leptospira spp. antibodies in cetaceans and manatees of the Amazon basin and Atlantic Ocean, Brazil.

Aquatic mammals can act as sentinels of emerging and resurging pathogens in the environment. Brucella spp. and Leptospira spp. are 2 zoonotic pathogens relevant to aquatic mammals, and their detection can be used to assess pathogen exposure. In this study, serum from 84 individuals-63 cetaceans (families Iniidae, n = 37; Delphinidae, n = 22; and Kogiidae, n = 4) and 21 West Indian manatees Trichechus manatus-was tested by the Rose Bengal Test (RBT) and a commercial competitive enzyme-linked immunosorbent assay (c-ELISA) for detecting Brucella spp. antibodies, and the microscopic agglutination test (MAT) for screening Leptospira spp. exposure. Overall, 4.8% (3/63) of cetaceans were positive by RBT and 15.9% (10/63) by c-ELISA for Brucella spp. Serum from 8 c-ELISA positive cetaceans (with available serum) was further tested via serum agglutination test (SAT) and 1 individual was positive. c-ELISA was more sensitive than RBT. Exposure to Brucella spp. was found in 5 cetacean species: Clymene dolphin Stenella clymene, short-finned pilot whale Globicephala macrorhynchus, pygmy killer whale Feresa attenuata, melon-headed whale Peponocephala electra and Atlantic bottlenose dolphin Tursiops truncatus in the Atlantic Ocean, Brazil, expanding the range of known Brucella seropositive aquatic hosts. No evidence of Brucella spp. exposure was found in Iniidae and Kogiidae odontocetes and manatees. Antibodies against Leptospira spp. were not detected in cetaceans and sirenians by MAT. These results contribute to the evaluation of different Brucella spp. serological methods in cetaceans and manatees and highlight the epidemiology of zoonotic pathogens in aquatic mammals of the southwestern Atlantic Ocean and the Amazon basin.

Antimicrobial Photodynamic Inactivation Mediated by Rose Bengal and Erythrosine Is Effective in the Control of Food-Related Bacteria in Planktonic and Biofilm States.

The thermal and chemical-based methods applied for microbial control in the food industry are not always environmentally friendly and may change the nutritional and organoleptic characteristics of the final products. Moreover, the efficacy of sanitizing agents may be reduced when microbial cells are enclosed in biofilms. The objective of this study was to investigate the effect of photodynamic inactivation, using two xanthene dyes (rose bengal and erythrosine) as photosensitizing agents and green LED as a light source, against Staphylococcus aureus, Listeria innocua, Enterococcus hirae and Escherichia coli in both planktonic and biofilm states. Both photosensitizing agents were able to control planktonic cells of all bacteria tested. The treatments altered the physicochemical properties of cells surface and also induced potassium leakage, indicating damage of cell membranes. Although higher concentrations of the photosensitizing agents (ranging from 0.01 to 50.0 µmol/L) were needed to be applied, the culturability of biofilm cells was reduced to undetectable levels. This finding was confirmed by the live/dead staining, where propidium iodide-labeled bacteria numbers reached up to 100%. The overall results demonstrated that photoinactivation by rose bengal and erythrosine may be a powerful candidate for the control of planktonic cells and biofilms in the food sector.

Mechanisms of interaction of biodegradable polyester nanocapsules with non-phagocytic cells.

The interaction of polymer nanocapsules (NC) prepared from four biodegradable polyesters with variable polymer hydrophobicity (PCL, PLA, PLGA and PLA-PEG) was investigated in the non-phagocytic Vero, Caco-2 and HepG2 cell lines. The NC, labeled with the highly lipophilic fluorescent indocarbocyanine dye DIL, had very similar sizes (approx. 140 nm) and negative zeta-potentials. Asymmetric flow field-flow fractionation evidenced NC colloidal stability and negligible transfer of the dye to serum proteins in the incubation medium. The cytotoxicity of the NC was evaluated via MTT assay over a large polymer concentration range (1-1000 µg/mL) and time of exposure (2, 24 and 48 h). The NC were safe in vitro up to a concentration of approx. 100 µg/mL or higher, depending on the cell line and nature of the polymer. Vero cells were more sensitive to the NC, in particular NC of the more hydrophobic polymer. The cells were exposed to endocytosis inhibitors, incubated with NC, and the cell-associated fluorescence was quantified by spectrofluorometry. HepG2 cells presented a 1.5-2-fold higher endocytic capacity than Caco-2 and Vero cells. The main mechanism of NC uptake was caveolin-mediated endocytosis in HepG2 and Vero cells, and macropinocytosis in Caco-2 cells. Polymer hydrophobicity had an effect on the level of NC associated to HepG2 cells and to a lesser extent on the endocytosis mechanisms in Vero and Caco-2 cells. The NC uptake levels and endocytosis mechanisms differed significantly between cell lines tested.

Preparation of PLGA/Rose Bengal colloidal particles by double emulsion and layer-by-layer for breast cancer treatment.

The use of colloidal particles (CPs) in the transport of drugs is developing rapidly thanks to its effectiveness and biosafety, especially in the treatment of various types of cancer. In this study Rose Bengal/PLGA CPs synthesized by double emulsion (W/O/W) and by electrostatic adsorption (layer-by-layer), were characterized and evaluated as potential breast cancer treatment. CPs were evaluated in terms of size, zeta potential, drug release kinetics and cell viability inhibition efficacy with the triple negative breast cancer cell line HCC70. The results showed that both types of CPs can be an excellent alternative to conventional cancer treatment by taking advantage of the enhanced permeation and retention (EPR) effect, manifested by solid tumors; however, the double emulsion CPs showed more suitable delivery times of up to 60% within two days, while layer-by-layer showed fast release of 50% in 90 min. Both types of CPs were capable to decrease cell viability, which encourage us to further testing in in vivo models to prove their efficacy and feasible use in the treatment of triple negative breast cancer.

Photodynamic Therapy With Bengal Rose and Derivatives Against Leishmania amazonensis.

Introduction: The treatment of cutaneous leishmaniasis (CL) is based primarily on the use of pentavalent antimonials, which may lead to many side effects limiting their use. Photodynamic therapy (PDT) is an alternative for the treatment of CL, and some xanthene dyes have the potential for use in PDT. Methods: The xanthenes rose bengal B (RB) and its derivatives rose bengal methyl ester (RBMET), and butyl ester (RBBUT) were analyzed for leishmanicidal activity against promastigotes and intracellular amastigotes of Leishmania amazonensis. Cytotoxicity was assessed in J774.A1 macrophages. Results: RB derivates RBMET (IC50 9.83 µM), and RBBUT (IC50 45.08 µM) showed leishmanicidal activity, however, were toxic to J774.A1 macrophages, resulting in low selectivity index. Conclusion: The RBMET and RBBUT showed to be effective against the L. amazonensis and the low selectivity index presented may not be a limitation for their use in PDT to CL treatment.

Vancomycin-sensitized photooxidation in the presence of the natural pigment vitamin B2: Interaction with excited states and photogenerated ROS.

Sensitized photooxidation processes in the presence of natural pigments may provide an alternative to antibiotics degradation since these compounds are transparent to natural light irradiation, therefore, they can be degraded by the action of photosensitizers which absorb light and produce highly reactive species, especially those derived from molecular oxygen (ROS). Most antibiotics used currently belong to a group of pharmaceutical substances that have been considered a new type of contaminants due to their persistence and bioaccumulation in the environment. OBJECTIVE: In this context, we decided to investigate the kinetic and mechanistic aspects of Vancomycin (Vanco) photosensitized degradation in the presence of the natural pigment Riboflavin (Vitamin B2, Rf) and the artificial dye Rose Bengal (RB) for comparative purposes. METHODS: The study have been done by using Stationary photolysis, Laser flash photolysis, Time-resolved phosphorence detection of O2(1Δg) experiments and Bactericidal activity evaluation. The experiments were carried out in aqueous solution at different pH values in order to establish relationships between the structure of the compound and its susceptibility to ROS-mediated photooxidation. RESULTS: Experimental evidence indicates that in the presence of Rf there is considerable contribution of the radical-mediated mechanism, while in the presence of RB the photooxidation process occurs exclusively through O2(1Δg) and the reactivity to this excited species increases with increasing pH of the environment. DISCUSSION: The results obtained, have been shown that Rf can raise the photodegradation of Vanco by both the radical pathway and the O2(1Δg) mediated. Furthermore, the antibiotic is able to interact with the excited electronic states of Rf as well as O2(1Δg) generated by energy transfer between the excited triplet state of the photosensitizer and the oxygen ground state. The predominant mechanism for photodegradation of Vanco in the presence of the Rf is the radical via because of the considerable interaction with the excited triplet state of the photosensitizer demonstrated by laser flash photolysis experiments. Microbiological test on Staphylococcus aureus ATCC25923 showed that the bactericidal activity of the antibiotic on the strain studied was affected by the sensitized photodegradation process, suggesting that photoproducts generated eventually do not retain the bactericidal properties of the original antibiotic.

Seroprevalencia de Brucella sp. en équidos de Córdoba, Colombia / Brucella sp. seroprevalence in equids of Córdoba, Colombia

La brucelosis es considerada una de las zoonosis más importantes en el mundo por sus implicaciones en la salud pública y sus repercusiones en la producción pecuaria. En la especie equina, la presentación de esta enfermedad es importante, debido a que estos animales son huéspedes potenciales y contribuyen con la introducción de la enfermedad en zonas no afectadas, así como el mantenimiento en donde ocurre de forma endémica. En el departamento de Córdoba no se registran estudios recientes que establezcan la prevalencia y características epidemiológicas de la enfermedad en équidos. El objetivo del presente estudio fue estimar la prevalencia de Brucella sp. en équidos del departamento de Córdoba. Se realizó un estudio descriptivo de corte transversal que incluyó 506 équidos procedentes de 14 municipios del departamento. Fueron estudiados tres especies: equinos (n=257), asnales (n=130) y mulares (n=119), procedentes de 46 predios. Las técnicas empleadas para el diagnóstico serológico fueron aglutinación rápida en placa Rosa de Bengala (n=506) y la confirmatoria fue con el ELISA competitiva (n=23). Se realizó la PCR convencional amplificando la región IS711de Brucella sp. a partir de muestras de exudado (n=2) y sangre con EDTA (n=4). La seroprevalencia de brucelosis en équidos fue del 4,5 % (23/506) por Rosa de Bengala (RB), con una distribución por especies de: equinos 20, asnos 2 y mulas 1. Con el ELISA competitiva (ELISA-C) la seroprevalencia fue del 4,3% (1/23), mientras que por PCR no se detectó ADN bacteriano en las seis muestras analizadas. La positividad en predios fue del 28,2% (13/46). Las cifras de seroprevalencia obtenidas en el presente estudio, demuestran la importancia de la vigilancia en las diferentes especies susceptibles a la brucelosis.

Brucellosis is considered one of the most important zoonotic diseases in the world because of its implications for public health and its impact on livestock production. In the equine species, the presentation of this disease is important, because these animals are potential hosts and contribute to the introduction of the disease in unaffected areas, as well as to the maintenance of this disease in endemic zones. In the Department of Córdoba, Colombia, there have been no recent studies that establish the prevalence and epidemiological characteristics of the disease in equids. The purpose of the present study was to estimate the prevalence of Brucella sp. in equids of the department of Córdoba. A cross-sectional descriptive study was carried out involving 506 equids from 14 municipalities of the department. Three species from 46 farms were studied: horses (n=257), asses (n=130) and mules (n=119). The techniques used for the serological diagnosis were: rapid agglutination, which was performed in 506 equids, using the Bengal Rose (RB) method; and the confirmatory method was performed on 23 equids, using the competitive ELISA tecnique (C-ELISA). Conventional PCR was performed by amplifying the IS711 region of Brucella sp. from exudate samples (n=2) and EDTA blood (n=4). The results of the study showed that the seroprevalence of brucellosis in equids was 4.5% (23/506) using the RB methodology, with the following distribution by species: 20 horses, 2 asses and 1 mule. With the C-ELISA technique, the seroprevalence was 4.3% (1/23), whereas by PCR no bacterial DNA was detected in the six samples analyzed. The positivity in farms was 28.2% (13/46). In conclusion, the seroprevalence figures obtained in the present study demonstrate the importance of epidemiological surveillance in the different species susceptible to brucellosis.

Silica nanoparticles doped with anthraquinone for lung cancer phototherapy.

In the present study, SiO2 nanoparticles functionalized with 3-(2-aminoethylamino)propyl group (SiNP-AAP) were used, for the first time, to covalently bond rose bengal (SiNP-AAP-RB) or 9,10-anthraquinone-2-carboxylic acid (SiNP-AAP-OCAq). The functionalized SiNP were characterized by: Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM); elemental analysis (CHN) for determination of the dye concentration; FTIR and UV-vis diffuse reflectance (DR-UV-vis) and a surface area study (BET). The functionalized SiNPs were applied in photodynamic therapy (PDT) against lung cancer cell lines. The evaluated cytotoxicity revealed 20-30% cell survival after 15min of PDT for both materials but the OCAq concentration was half of the RB nanomaterial. The phototoxicity was mainly related to oxidative stress generated in the cellular environment by singlet oxygen and by hydrogen abstraction as confirmed by the laser flash photolysis technique. The unprecedented results indicate that SiNP-AAP-OCAq is a possible system for promoting cell apoptosis by both type I and type II mechanisms.

Varón marroquí con espondilodiscitis de larga evolución, orquitis y endocarditis / Moroccan man with longstanding spondylodiscitis, orchitis and endocarditis

La afectación osteoarticular es la complicación más frecuente de la brucelosis. La espondilodiscitis es una complicación grave, ya que suele estar asociada con la formación de abscesos. Se presenta el caso de un varón de 43 años de edad, natural de Marruecos, con síntomas, signos y hallazgos imagenológicos de espondilodiscitis de larga evolución, orquitis y endocarditis. Mediante la realización de pruebas de laboratorio complementarias se llega al diagnóstico de infección por Brucella spp. El presente caso busca concientizar a la comunidad médica sobre la importancia de considerar la infección por Brucella spp. como diagnóstico diferencial en pacientes con sospecha de espondilodiscitis infecciosa, especialmente en aquellos pacientes con antecedentes epidemiológicos, permitiendo así realizar un acertado y oportuno diagnóstico. Este caso resulta interesante porque nunca antes se había descrito la presencia simultánea de estas tres manifestaciones de la brucelosis en un paciente inmuno competente. (Acta Med Colomb 2015; 40: 166-168).

Osteoarticular involvement is the most common complication of brucellosis. Spondylodiscitis is a serious complication as it is often associated with abscess formation. The case of a 43 years old man born in Morocco with symptoms, signs and imaging findings of longstanding spondylodiscitis, orchitis and endocarditis is presented. Through the implementation of complementary laboratory tests, diagnosis infection by Brucella spp. was made.This case aims to raise awareness in the medical community about the importance of considering Brucella spp. as a differential diagnosis in patients with suspected infectious spondylodiscitis, especially in those patients with epidemiological background, allowing make a successful and timely diagnosis. This case is interesting because never before had been described the simultaneous presence of these three manifestations of brucellosis in an immunocompetent patient. (Acta Med Colomb 2015; 40: 166-168).

Impact of wildfire smoke in Buenos Aires, Argentina, on ocular surface / Efeitos da fumaça de incêndios na superfície ocular em Buenos Aires, Argentina

Purpose: To evaluate the acute impact of the wildfire smoke episode in 2008 on the ocular surface of subjects living in the Metropolitan Area of Buenos Aires (MABA). Methods: A total of 86 subjects were evaluated: Group 1 comprised patients from a public ophthalmology hospital (N=35) and Group 2 comprised healthy volunteers (N=51). All subjects answered a questionnaire on ocular symptoms and underwent ophthalmologic examination [bulbar conjunctival hyperemia, corneal fluorescein staining, rose bengal vital staining, tear break-up time (TBUT), Schirmer I test, tear lysozyme, and impression cytology] during and after the acute episode. Concentrations of carbon monoxide (CO), nitrogen dioxide (NO2), and particulate matter (PM) were measured before, during, and after the acute episode. Results: Both groups showed a statically significant increase in ocular symptoms and bulbar conjunctival hyperemia and a statically significant decrease in tear break-up time during the acute episode. Group 1 showed more severe symptoms and a statistically significant increase in fluorescein and rose bengal staining intensities during the acute episode. We found a significant negative correlation between ocular symptoms and tear break-up time. During the episode, the levels of CO, NO2, and particulate matter in MABA were four times higher than the usual average levels for the same period in 2007 and 2009. Conclusions: Increased air pollution from the burning of biomass is associated with a decrease in the stability of the tear film (TBUT), generating areas of ocular surface exposure that may be the cause of the increased feeling of irritation. Group 1 was more affected by not having a healthy ocular surface, and thus consulted an ophthalmologist. Cytological changes in the conjunctiva were not observed, which could be due to the short duration of the episode. .

Objetivo: Avaliar os efeitos agudos da fumaça do episódio de incêndio violento ocorrido em 2008, sobre a superfície ocular de sujeitos que vivem na Região Metropolitana de Buenos Aires (MABA). Métodos: Um total de 86 indivíduos foram avaliados: Grupo 1: pacientes de um hospital público de oftalmologia (N=35) e Grupo 2: voluntários saudáveis (N=51). Todos os participantes responderam a um questionário sobre os sintomas oculares e foram submetidos a exame oftalmológico (hiperemia conjuntival bulbar, teste de fluoresceína, corante rosa bengala, tempo de ruptura do filme lacrimal (TBUT), teste de Schirmer I, lisozima lacrimal e citologia de impressão) durante e após o episódio agudo. As concentrações de monóxido de carbono, dióxido de nitrogênio e partículas (PM) foram medidas antes, durante e após o episódio agudo. Resultados: Ambos os grupos apresentaram aumento estatisticamente significativo dos sintomas oculares, hiperemia conjuntival bulbar, e diminuição estatisticamente significativa no tempo de ruptura do filme lacrimal durante o episódio agudo. Grupo 1 apresentou maior intensidade dos sintomas e aumento estatisticamente significativo no teste de fluoresceína e rosa bengala durante o episódio agudo. Encontramos uma correlação negativa significativa entre os sintomas oculares e tempo de ruptura do filme lacrimal. Durante o episódio agudo de 2008, os níveis de CO, NO2 e PM na Região Metropolitana de Buenos Aires foram 4 vezes maiores do que os níveis médios habituais para o mesmo período de 2007 e 2009. Conclusões: O aumento da poluição do ar a partir da queima de biomassa está associado a uma diminuição da estabilidade do filme lacrimal (TBUT) gerando zonas da exposição da superfície ocular, que podem ser a causa do aumento da sensação de irritação. Grupo 1 foi mais afetado por não ter superfície ocular saudável e, portanto, consultaram um oftalmologista. Mudanças citológicas da conjuntiva não foram observadas e isso poderia ser devido ...