Microalgae extracts modulates the immune response in Trypanosoma cruzi-infected human cells.

Chagas disease (CD) is caused by the hemoflagellate protozoan Trypanosoma cruzi. The control of the infection depends of the innate and acquired immune response of host. Moreover, CD plays a significant role in the immune response, and, in this context, microalgae can be an interesting alternative due to its immunomodulatory and trypanocidal effects. This study aimed to evaluate, in vitro, immunomodulatory potentials of the aqueous extracts of Chlorella vulgaris and Tetradesmus obliquus. Both microalgae extracts (ME) were obtained by sonication, and the selectivity index (SI) was determined by assays of inhibitory concentration (IC50) in T. cruzi trypomastigotes cells; as well as the cytotoxic concentrations (CC50) in human peripheral mononuclear cells (PBMC). The immune response was evaluated in T. cruzi-infected PBMC using the IC50 value. ME led to inhibition of T. cruzi trypomastigotes after 24 h of treatment, in which the IC50 values were 112.1 µg/ml to C. vulgaris and 15.8 µg ml-1 to T. obliquus. On the other hand, C. vulgaris did not affect the viability of PBMCs in concentrations up to 1000 µg ml-1, while T. obliquus was non-toxic to PBMCs in concentrations up to 253.44 µg ml-1. In addition, T. obliquus displayed a higher SI against T. cruzi (SI = 16.8), when compared with C. vulgaris (SI = 8.9). C. vulgaris decreased the levels of IFN, indicating a reduction of the inflammatory process; while T. obliquus displayed an interesting immunomodulatory effect, since discretely increased the levels of TNF and stimulated the production of the anti-inflammatory cytokine IL-10. This study confirms that ME are effective against T. cruzi trypomastigotes, and may able to control the parasitemia and preventing the progress of CD while regulating the inflammatory process.

Atomistic insights from DFT calculations into the catalytic properties on ceria-lanthanum clusters for methane activation.

Improving the catalytic performance of materials based on cerium oxide (CeO2) for the activation of methane (CH4) can be achieved through the following strategies: mixture of CeO2 with different oxides (e.g., CeO2-La2O3) and the use of particles with different sizes. In this study, we present a theoretical investigation of the initial CH4 dehydrogenation on (La2Ce2O7)n clusters, where n = 2, 4, and 6. Our framework relies on density functional theory calculations combined with the unity bond index-quadratic exponential potential approximation. Our results indicate that chemical species arising from the first dehydrogenation of CH4, that is, CH3 and H, bind through the formation of C-O and H-O bonds with the clusters, respectively. The coordination of the adsorption site and the chemical environment plays a crucial role in the magnitude of the adsorption energy; for example, species adsorb more strongly in the low-coordinated topO sites located close to the La atoms. Thus, it affects the activation energy barrier, which tends to be lower in configurations where the adsorption of the chemical species is stronger. During CH4 dehydrogenation, the CH3 radical can be present in a planar or tetrahedral configuration. Its conformation changes as a function of the charge transference between the molecule and the cluster, which depends on the CH3-cluster distance. Finally, we analyze the effects of the Hubbard effective parameter (Ueff) on adsorption properties, as the magnitude of localization of Ce f-states affects the hybridization of the interaction between the molecule and the clusters and hence the magnitude of the adsorption energies. We obtained a linear decrease in the adsorption energies by increasing the Ueff parameter; however, the activation energy is only slightly affected.

Cost-effective fibrinolytic enzyme production by microalga Dunaliella tertiolecta using medium supplemented with corn steep liquor.

A fibrinolytic enzyme from the microalga Dunaliella tertiolecta was produced under mixotrophic conditions using different corn steep liquor (CSL) concentrations ( 0 ≤ CLS ≤ 0.75%), purified using a combination of salting out and ion-exchange chromatography, and then biochemical characterized. Cultivation of this microalga using 0.5% CSL led to the highest maximum cell concentration (1.960±0.010 mg L-1) and cell productivity (0.140g L-1 day-1), besides a high fibrinolytic activity of the extract obtained by the homogenization method (102 ±1 U mL-1). The enzyme extracted from the microalgal biomass was 5-fold purified with a 20% yield and was found to have a specific activity of 670 U mg-1. The enzyme, whose molecular weight determined by fibrin zymography was 10 kDa, was shown to be stable at pH 3.0-9.0 and up to 70°C with optimal pH and temperature values of 8.0 and 50°C, respectively. When compared to other fibrinolytic enzymes, this protease stood out for its high fibrinolytic activity, which was enhanced by Fe2+, inhibited by Zn2+, Cu2+, Mg2+, and Ca2+, and strongly inhibited by phenylmethylsulfonyl fluoride, suggesting that it belongs to the serine metalloprotease family. Moreover, thanks to its thermal stability, the enzyme may be easily preserved and activated under high-temperature conditions.

Computational investigation of van der Waals corrections in the adsorption properties of molecules on the Cu(111) surface.

Here, we report a computational investigation on the role of the most common van der Waals (vdW) corrections (D2, D3, D3(BJ), TS, TS+SCS, TS+HI, and dDsC) employed in density functional theory (DFT) calculations within local and semilocal exchange-correlation functionals to improve the description of the interaction between molecular species and solid surfaces. For this, we selected several molecular model systems, namely, the adsorption of small molecules (CH3, CH4, CO, CO2, H2O, and OH) on the close-packed Cu(111) surface, which bind via chemisorption or physisorption mechanisms. As expected, we found that the addition of the vdW corrections enhances the energetic stability of the Cu bulk in the face-centered cubic structure, which contributes to increasing the magnitude of the mechanical properties (elastic constants, bulk, Young, and shear modulus). Except for the TS+SCS correction, all vdW corrections substantially increase the surface energy, while the work function changes by about 0.05 eV (largest change). However, we found substantial differences among the vdW corrections when comparing its effects on interlayer spacing relaxations. Based on bulk and surface results, we selected only the D3 and dDsC vdW corrections for the study of the adsorption properties of the selected molecules on the Cu(111) surface. Overall, the addition of these vdW corrections has a greater effect on weakly interacting systems (CH4, CO2, H2O), while the chemisorption systems (CH3, CO, OH) are less affected.

Photosynthetic microorganisms and their bioactive molecules as new product to healing wounds.

Wounds are a public health problem due to long periods required to repair damaged skin, risk of infection, and amputations. Thus, there is a need to obtain new therapeutic agents with less side effects, more effective oxygen delivery, and increased epithelial cell migration. Photosynthetic microorganisms, such as microalgae and cyanobacteria, may be used as a source of biomolecules for the treatment of different injuries. The aim of this review article focuses on healing potential using phytoconstituents from photosynthetic microorganisms. Cyanophyte Spirulina and Chlorophyte Chlorella are more promising due to steroids, triterpenes, carbohydrates, phenols, and proteins such as lectins and phycocyanin. However, there are few reports about identification and specific function of these molecules on the skin. In other microalgae and cyanobacteria genus, high contents of pigments such as ß-carotene, chlorophyll a, allophycocyanin, and hydroxypheophytin were detected, but their effects on phases of wound healing is absent yet. The development of new topical drugs from photosynthetic microorganisms could be a potential alternative to maximize healing. KEY POINTS: • Conventional treatment to skin injuries has limitations. • Proteins, terpenes, and phenols increase collagen deposition and re-epithelialization. • Microalgae and cyanobacteria may be used as a source of biomolecules to wound healing.

Algae as a source of peptides inhibitors of the angiotensin-converting enzyme: a systematic review.

Hypertension is a factor that contributes to the risk of chronic diseases. The inhibition of angiotensin-I converting enzyme (ACE) is a useful therapeutic approach to the hypertension treatment. The algae have been an alternative for the production of ACE inhibitory (ACEi) peptides from enzymatic hydrolysis due to their protein-rich biomass. The aim of this study was to systematically review the literature regarding the production, composition and activity of ACEi peptides derived from algae proteins. Systematic database searches identified 648 related articles. Among these, only 14 were selected according to the eligibility criteria to this review. Macroalgae are more studied than microalgae as sources of ACEi peptides. Furthermore, hydrolysates by thermolysin or bromelain exhibited the highest ACEi activity compared to other enzymes. The main features of the peptides with high ACE inhibition are low molecular weight, short amino acids sequence and non-competitive inhibition pattern. In vivo studies using hydrolysates and peptides derived from algae proteins showed antihypertensive activity in spontaneously hypertensive rats (SHR). Thus, it is suggested that ACEi peptides derived from algae can be considered as potential antihypertensive.

Role of the OH-group in the adsorption properties of methanol, ethanol, and ethylene glycol on 15-atom 3d, 4d, and 5d transition-metal clusters.

The adsorption of alcohols on transition-metal (TM) substrates has received the attention of many researchers due to the applications of alcohols in several technological fields. However, our atomic-level understanding is still far from satisfactory, in particular for the interaction of alcohols with finite-size TM clusters, where new effects can arise due to the presence of quantum-size effects. In this work, we report a theoretical investigation of the adsorption properties of methanol, ethanol, and ethylene glycol on 12 different 3d, 4d, and 5d TM15 clusters based on density functional theory calculations within the semi-empirical D3 van der Waals corrections. From the correlation analysis of all the lowest- and high-energy configurations, we identified the adsorption modes of methanol, ethanol, and ethylene glycol on the TM15 clusters, in which the OH group binds to the cationic TM sites via the O-TM and H-TM interactions. Due to the relatively weak alcohol-TM15 interaction, the changes induced on the TM15 clusters are small, except for Au15 and Ru15, where the bare cluster changes its structure to a nearby minimum in the potential energy surface. The adsorption energy for the alcohol/TM15 systems is correlated to the combination of several parameters, in which the main contribution is connected with the O-TM interaction and the HOTM angles. Furthermore, the TM electronegativity is an important descriptor for the methanol and ethanol adsorption energies, while charge transfer is important for ethylene glycol.

Ab initio investigation of the role of transition-metal dopants in the adsorption properties of ethylene glycol on doped Pt(100) surfaces.

Ethylene glycol (EG) has been considered as a promising alcohol for direct alcohol fuel cells, however, our atomistic understanding of its interaction with doped transition-metal (TM) substrates is not well established. Here, we employed density functional theory calculations within the additive van der Waals D3 correction to improve our atomistic understanding of the role of TM dopants on the adsorption properties of EG on undoped and doped Pt(100) surfaces, namely, Pt8TM1/Pt9/Pt(100) and Pt9/Pt8TM1/Pt(100), where substitutional TM dopants (Fe, Co, Ni, Ru, Rh and Pd) are located within the topmost or subsurface Pt(100) layers, respectively. Except for Pd, all the studied TM dopants showed strong energetic preference for the subsurface layer, which can be explained by the segregation energy and charge effects, and it is not affected by the EG adsorption. In the lowest energy configurations of the undoped and doped substrates, EG binds via one OH group, with the anionic O atom located close to the on-top cationic TM site and the H atom parallel to the surface and pointing towards the bridge site. However, at slightly higher energy configurations, EG adsorbs via one OH with the C-C bond almost perpendicular to the surface, or via both OH groups. As expected, the adsorption is stronger on Pt8TM1/Pt9/Pt(100) with EG (OH group) bound to the cationic TM site and a O-TM distance of about 2 Å. Furthermore, doping enhanced the adsorption energy, and hence, decreased the distance between EG and the surface. For all substrates, adsorption induces a reduction of the work function, which is larger for the adsorption of EG via two OH groups.

Purification of a lectin from Cratylia mollis crude extract seed by a single step PEG/phosphate aqueous two-phase system.

The partitioning and purification of lectins from the crude extract of Cratylia mollis seeds (Cramoll 1,4) was investigated in aqueous two-phase systems (ATPS). A factorial design model (24) was used to evaluate the influence of polyethylene glycol (PEG) molar mass (1500-8000 g/mol), PEG concentration (12.5-17.5% w/w), phosphate (10-15% w/w) concentration, and pH (6-8) on the differential partitioning, purification factor, and yield of the lectin. Polymer and salt concentration were the most important variables affecting partition of lectin and used to find optimum purification factor by experimental Box-Behnken design together with the response surface methodology (RSM). ATPS showed best conditions composed by 13.9% PEG1500, 15.3% phosphate buffer at pH 6, which ensured purification factor of 4.70. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed a single band of protein with 26.1 kDa. Furthermore, results demonstrated a thermostable lectin presenting activity until 60 °C and lost hemagglutinating activity at 80 °C. According to the obtained data it can be inferred that the ATPS optimization using RSM approach can be applied for recovery and purification of lectins.

Big Data Approaches to Phenotyping Acute Ischemic Stroke Using Automated Lesion Segmentation of Multi-Center Magnetic Resonance Imaging Data.

Background and Purpose- We evaluated deep learning algorithms' segmentation of acute ischemic lesions on heterogeneous multi-center clinical diffusion-weighted magnetic resonance imaging (MRI) data sets and explored the potential role of this tool for phenotyping acute ischemic stroke. Methods- Ischemic stroke data sets from the MRI-GENIE (MRI-Genetics Interface Exploration) repository consisting of 12 international genetic research centers were retrospectively analyzed using an automated deep learning segmentation algorithm consisting of an ensemble of 3-dimensional convolutional neural networks. Three ensembles were trained using data from the following: (1) 267 patients from an independent single-center cohort, (2) 267 patients from MRI-GENIE, and (3) mixture of (1) and (2). The algorithms' performances were compared against manual outlines from a separate 383 patient subset from MRI-GENIE. Univariable and multivariable logistic regression with respect to demographics, stroke subtypes, and vascular risk factors were performed to identify phenotypes associated with large acute diffusion-weighted MRI volumes and greater stroke severity in 2770 MRI-GENIE patients. Stroke topography was investigated. Results- The ensemble consisting of a mixture of MRI-GENIE and single-center convolutional neural networks performed best. Subset analysis comparing automated and manual lesion volumes in 383 patients found excellent correlation (ρ=0.92; P<0.0001). Median (interquartile range) diffusion-weighted MRI lesion volumes from 2770 patients were 3.7 cm3 (0.9-16.6 cm3). Patients with small artery occlusion stroke subtype had smaller lesion volumes ( P<0.0001) and different topography compared with other stroke subtypes. Conclusions- Automated accurate clinical diffusion-weighted MRI lesion segmentation using deep learning algorithms trained with multi-center and diverse data is feasible. Both lesion volume and topography can provide insight into stroke subtypes with sufficient sample size from big heterogeneous multi-center clinical imaging phenotype data sets.

Ethanol effect on batch and fed-batch Arthrospira platensis growth.

The ability of Arthrospira platensis to use ethanol as a carbon and energy source was investigated by batch process and fed-batch process. A. platensis was cultivated under the effect of a single addition (batch process) and a daily pulse feeding (fed-batch process) of pure ethanol, at different concentrations, to evaluate cell concentration (X) and specific growth rate (µ). A marked increase was observed in the cell concentration of A. platensis in runs with ethanol addition when compared to control cultures without ethanol addition. The fed-batch process using an ethanol concentration of 38 mg L(-1) days(-1) reached the maximum cell concentration of 2,393 ± 241 mg L(-1), about 1.5-fold that obtained in the control culture. In all experiments, the maximum specific growth rate was observed in the early exponential phase of cell growth. In the fed-batch process, µ decreased more slowly than in the batch process and control culture, resulting in the highest final cell concentration. Ethanol can be used as a feasible carbon and energy source for A. platensis growth via a fed-batch process.

Subtle white matter intensity changes on fluid-attenuated inversion recovery imaging in patients with ischaemic stroke.

Leukoaraiosis is a neuroimaging marker of small-vessel disease that is characterized by high signal intensity on fluid-attenuated inversion recovery MRI. There is increasing evidence from pathology and neuroimaging suggesting that the structural abnormalities that characterize leukoaraiosis are actually present within regions of normal-appearing white matter, and that the underlying pathophysiology of white matter damage related to small-vessel disease involves blood-brain barrier damage. In this study, we aim to verify whether leukoaraiosis is associated with elevated signal intensity on fluid-attenuated inversion recovery imaging, a marker of brain tissue free-water accumulation, in normal-appearing white matter. We performed a cross-sectional study of adult patients admitted to our hospital with a diagnosis of acute ischaemic stroke or transient ischaemic attack. Leukoaraiosis was segmented using a semi-automated method involving manual outlining and signal thresholding. White matter regions were segmented based on the probabilistic tissue maps from the International Consortium for Brain Mapping 152 atlas. Also, normal-appearing white matter was further segmented based on voxel distance from leukoaraiosis borders, resulting in five normal-appearing white matter strata at increasing voxel distances from leukoaraiosis. The relationship between mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter and leukoaraiosis volume was studied in a multivariable statistical analysis using linear mixed modelling, having normal-appearing white matter strata as a clustering variable. One hundred consecutive patients meeting inclusion and exclusion criteria were selected for analysis (53% female, mean age 68 years). Mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was higher in the vicinity of leukoaraiosis and progressively lower at increasing distances from leukoaraiosis. In a multivariable analysis, the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter was positively associated with leukoaraiosis volume and age (B = 0.025 for each leukoaraiosis quartile increase; 95% confidence interval 0.019-0.030). This association was found similarly across normal-appearing white matter strata. Voxel maps of the mean normalized fluid-attenuated inversion recovery signal intensity on normal-appearing white matter showed an increase in signal intensity that was not adjacent to leukoaraiosis regions. Our results show that normal-appearing white matter exhibits subtle signal intensity changes on fluid-attenuated inversion recovery imaging that are related to leukoaraiosis burden. These results suggest that diffuse free-water accumulation is likely related to the aetiopathogenic processes underlying the development of white matter damage related to small-vessel disease.

Acetylcholinesterase purification from human erythrocytes using magnetic nanoparticles containing procainamide.

This work presents a magnetic purification method of human erythrocyte Acetylcholinesterase (EC 3.1.1.7; AChE) based on affinity binding to procainamide (Proca) as ligand. Acetylcholinesterase is an acetylcholine-regulating enzyme found in different areas of the body and associated with various neurological disorders, such as Parkinson, Alzheymer and Amyotrophic Lateral Sclerosis. AChE from human erythrocyte purification has been attempted in recent years with low degree of purity. Here, magnetic nanoparticles (MNP) were synthesized and coated with polyaniline (PANI) and procainamide (PROCA) was covalently linked to the PANI. The extracted human erythrocyte AChE formed a complex with the MNP@PANI-PROCA and an external magnet separated it from the undesired proteins. Finally, the enzyme was collected by increasing the ionic strength. Experimental Box-Behnken design was developed to optimize this process of human erythrocyte AChE purification protocol. The enzyme was purified in all fifteen experiments. However, the best AChE purification result was achieved, about 2000 times purified, when 100 mg of MNP@PANI-PROCA was incubated for one hour with 4 ml hemolysate extract. The SDS-PAGE of this preparation presented a molecular weight of approximately 70 kDa, corroborating with few previous studies of AChE from erythrocyte purification.

Application of the galactomannan gel from Cassia grandis seeds for biomedical purposes: Study of the incorporation of collagenases and their release profile.

The galactomannan-based gel from Cassia grandis seeds was used to incorporate Penicillium sp. UCP 1286 and commercial collagenases. Experiments were carried out according to a 23-full factorial design to identify the most significant parameters for the incorporation process. The pH of the incorporation solution (pHi), stirring time (t), and initial protein concentration in the crude extract (PCi) were selected as the three independent variables, and the efficiency of collagenase incorporation (E) and collagenolytic activity (CA) after 360 min as the responses. pHi and PCi showed positive statistically significant effects on E, while CA was positively influenced by pHi and t, but negatively by PCi. The fungi collagenase was released from the gel following a pseudo-Fickian behavior. Additionally, no <76 % of collagenase was efficiently incorporated into the gel retaining a high CA (32.5-69.8 U/mL). The obtained results for the commercial collagenase (E = 93.88 %, CA = 65.8 U/mL, and n = 0.10) demonstrated a pseudo-Fickian behavior similar to the fungi-collagenase. The results confirm the biotechnological potential of the gel as an efficient matrix for the incorporation of catalytic compounds; additionally, the incorporation of collagenases was achieved by retaining the proteases CA and releasing them in a controlled manner.

Chlorella vulgaris extract and Imiquimod as new therapeutic targets for leishmaniasis: An immunological approach.

The therapeutic regimen for the treatment of American Tegumentary Leishmaniasis (ATL) is targeted at the death of the parasite; therefore, it is essential to develop a treatment that can act on the parasite, combined with the modulation of the inflammatory profile. Thus, the aim of this study was to make an in vitro evaluation of the therapeutic potential of Chlorella vulgaris extract (CV) and Imiquimod for ATL. Selectivity indices (SI) were determined by inhibitory concentration assays (IC50) in L. braziliensis cells and cytotoxic concentrations (CC50) were measured in human cells using the MTT method, based on the CV microalgae extract (IC50 concentrations of 15.63 to 500 µg/mL; CC50 concentrations of 62.5-1000 µg/mL) in comparison with the reference drugs and Imiquimod. The immune response was evaluated in healthy human cells by gene expression (RT-qPCR) and cytokine production (Flow Cytometry). The CV extract (SI = 6.89) indicated promising results by showing higher SI than meglumine antimoniate (SI = 3.44) (reference drug). In all analyses, CV presented a protective profile by stimulating the production of Th1 profile cytokines to a larger extent than the reference drugs. Imiquimod showed a high expression for Tbx21, GATA3, RORc and Foxp3 genes, with increased production only of the TNF cytokine. Therefore, the data highlight the natural extract and Imiquimod as strong therapeutic or adjuvant candidates against ATL, owing to modulation of immune response profiles, low toxicity in human cells and toxic action on the parasite.

Green microalgae as a potential source of trypanocide compounds.

Due to the limitations of Chagas disease therapy, microalgae can be promising in the search of new trypanocidal compounds, since these organisms produce bioactive compounds with large pharmaceutical applications, including antiparasitic effects. In this work, trypanocidal activity of aqueous extract of Tetradesmus obliquus and, for the first time, aqueous extract of Chlorella vulgaris, were evaluated against trypomastigote forms of Trypanosoma cruzi. In addition, cytotoxic activity in Vero cells was evaluated. Our results showed that C. vulgaris and T. obliquus present trypanocidal activity (IC50 = 32.9 µg ml-1 and 36.4 µg ml-1, respectively), however, C. vulgaris did not present cytotoxic effects in Vero cells (CC50 > 600 µg ml-1) and displayed a higher selectivity against trypomastigotes forms of T. cruzi (SI > 18). Thus, microalgae extracts, such as aqueous extract of C. vulgaris, are promising potential candidates for the development of natural antichagasic drugs.

Comparative study of structures and functional motifs in lectins from the commercially important photosynthetic microorganisms.

Photosynthetic microorganisms, specifically cyanobacteria and microalgae, can synthesize a vast array of biologically active molecules, such as lectins, that have great potential for various biotechnological and biomedical applications. However, since the structures of these proteins are not well established, likely due to the presence of intrinsically disordered regions, our ability to better understand their functionality is hampered. We embarked on a study of the carbohydrate recognition domain (CRD), intrinsically disordered regions (IDRs), amino acidic composition, as well as and functional motifs in lectins from cyanobacteria of the genus Arthrospira and microalgae Chlorella and Dunaliella genus using a combination of bioinformatics techniques. This search revealed the presence of five distinctive CRD types differently distributed between the genera. Most CRDs displayed a group-specific distribution, except to C. sorokiniana possessing distinctive CRD probably due to its specific lifestyle. We also found that all CRDs contain short IDRs. Bacterial lectin of Arthrospira prokarionte showed lower intrinsic disorder and proline content when compared to the lectins from the eukaryotic microalgae (Chlorella and Dunaliella). Among the important functions predicted in all lectins were several specific motifs, which directly interacts with proteins involved in the cell-cycle control and which may be used for pharmaceutical purposes. Since the aforementioned properties of each type of lectin were investigated in silico, they need experimental confirmation. The results of our study provide an overview of the distribution of CRD, IDRs, and functional motifs within lectin from the commercially important microalgae.

Therapeutic Potential of Photosynthetic Microorganisms for Visceral Leishmaniasis: An Immunological Analysis.

New therapeutic strategies for visceral leishmaniasis (VL) have been studied, and the development of an immunotherapeutic agent that modulates the host's immune response is necessary. The aim of this study was to evaluate in vitro the bioactive extracts of photosynthetic microorganisms (PMs) for their leishmanicidal/leishmanistatic and immunomodulatory potentials. Bioactive extracts from PMs (Arthrospira platensis and Dunaliella tertiolecta) were obtained by sonication. Reference drugs, miltefosine (MTF) and N-methylglucamine antimoniate (SbV), were also evaluated. The selectivity index (SI) of treatments was determined by assays of inhibitory concentration (IC50) in Leishmania infantum cells and cytotoxic concentrations (CC50) in human peripheral blood mononuclear cells by the MTT method. The immune response was evaluated in healthy human cells by the production of cytokines and nitric oxide (NO) and the gene expression of Tbx21, GATA3, RORc, and FOXP3, using four concentrations (CC50, ½ CC50, » CC50, and IC50) for in-vitro stimulation. Based on the data obtained, we observed that the extracts of D. tertiolecta (SI = 4.7) and A. platensis (SI = 3.8) presented better results when compared to SbV (SI = 2.1). When analyzing the immune response results, we identified that the extracts of PMs stimulated the production of cytokines of the Th1 profile more than the reference drugs. The extracts also demonstrated the ability to stimulate NO synthesis. Regarding gene expression, in all concentrations of A. platensis extracts, we found a balance between the Th1/Th2 profile, with the average expression of the Tbx21 gene more than the GATA3 in the highest concentration (CC50). Regarding the extract of D. tertiolecta, we can observe that, in the lowest concentrations, a balance between all the genes was present, with the average expression of the GATA3 gene being lower than the others. The best result was found in the ½ CC50 concentration, stimulating a balanced positive expression between the Th1×Th17×Treg profiles, with a negative expression of GATA3. Thus, PM extracts showed promising results, presenting low toxicity, leishmanicidal/leishmanistatic activity, and induction of the immune response, which could be potential therapeutic candidates for VL.

Diode Green Laser in the Lid Trichiasis Treatment.

PURPOSE: To validate the standard values and evaluate the success rate in the treatment of minor and major trichiasis using thermoablation with a diode green laser. METHODS: In this interventional prospective study, individuals with minor or major trichiasis who were treated with thermoablation using diode green laser were included. The patients' mean age was 72.1 years; the majority were females (54.1%) and Caucasian (98%). The parameters of the diode laser were wavelength of 532 nm, application time of 200 ms, target size of 50 µm, interval between the shots 150 to 200 ms, and power of 600 to 750 mW. The number of shots was defined by the depth of ablation sufficient to reach the pilus hair bulb. The patients were evaluated by slit-lamp every 3 to 4 months, for up to 15 months. The treatment success rate and the association between variables were analyzed. RESULTS: The study sample was comprised of 98 patients with 135 affected lids and 337 lashes with trichiasis. Minor trichiasis (91.8%), unilateral trichiasis (67.3%), trichiasis affecting the lower eyelid (85.9%), and trichiasis resulting from blepharitis (64.3%) were the most common presentation profiles. The overall cure rate at the end of the study was 85%, with 69% being cured with a single session and 82.8% with two treatment sessions. CONCLUSION: Thermoablation using a diode green laser applying the specified parameters to treat minor and major trichiasis is effective and results in high cure rate.

Bioactive Compounds of Arthrospira spp. (Spirulina) with Potential Anticancer Activities: A Systematic Review.

Arthrospira, a genus of blue-green cyanobacteria, is known for its great biological activity due to the presence of a large number of substances that are potentially active against tumor cells. This review aimed to evaluate the potential of Arthrospira spp. for the treatment or reduction of several types of cancer, in addition to elucidating the mechanism of action by which their compounds act on tumor cells. A systematic review was carried out in PubMed, Science Direct, LILACS, and SciELO databases, including original studies from 2009 to 2020. A total of 1306 articles were independently assessed according to the eligibility criteria, of which 20 articles were selected and assessed for the risk of bias using seven criteria developed by the authors. Arthrospira spp. of cyanobacteria have been evaluated against eight different types of cancer, mainly colon cancer. Among all the compounds, phycocyanin was the most used, followed by peptides and photosensitizers. In general, compounds from Arthrospira spp. act as anticancer agents by inhibiting the proliferation of tumor cells, triggering cell cycle arrest, and inducing apoptosis via different signaling pathways. In addition, these compounds also exhibited antioxidant, antiangiogenic, and antimetastatic activities. Phycocyanin demonstrated better efficacy against several types of cancer via different activities and therapeutic targets. Furthermore, it was the only molecule that functioned in synergy with other drugs that are already well established for the treatment of cancer.