Coastal natural products: a review applied to antimycobacterial activity.

Despite the many advances in drug research, natural products are still being explored as a promising source for discovering new bioactive compounds to treat global diseases such as tuberculosis. However, there is a lack of studies and information about coastal natural products, which thrive in the transitional environment between two different ecosystems and produce unique secondary metabolites. Mangroves, estuaries, and mudflats make up areas for coastal species and have shown promising results in antituberculosis research, some of them are present in hotspot areas. This review focuses on research conducted in coastal environments and explores the reasons why these natural products tend to outperform non-coastal ones against the causative agent of tuberculosis, Mycobacterium tuberculosis.

Larvicidal activity of coumarin derivatives on Toxocara canis larvae, cytotoxicity analysis, and in silico bioavailability studies.

Human toxocariasis is a neglected anthropozoonosis with global distribution. Treatment is based on the administration of anthelmintics; however, their effectiveness at the tissue level is low to moderate, necessitating the discovery of new drug candidates. Several groups of synthetic compounds, including coumarin derivatives, have demonstrated bioactivity against fungi, bacteria, and even parasites, such as Dactylogyrus intermedius, Leishmania major, and Plasmodium falciparum. The aim of this study was to evaluate the effect of ten coumarin-derived compounds against Toxocara canis larvae using in vitro, cytotoxicity, and in silico tests for selecting new drug candidates for preclinical tests aimed at evaluating the treatment of visceral toxocariasis. The compounds were tested in vitro in duplicate at a concentration of 1 mg/mL, and compounds with larvicidal activity were serially diluted to obtain concentrations of 0.5 mg/mL; 0.25 mg/mL; 0.125 mg/mL; and 0.05 mg/mL. The tests were performed in a microculture plate containing 100 T. canis larvae in RPMI-1640 medium. One compound (COU 9) was selected for cytotoxicity analysis using J774.A1 murine macrophages and it was found to be non-cytotoxic at any concentration tested. The in silico analysis was performed using computational models; the compound presented adequate results of oral bioavailability. To confirm the non-viability of the larvae, the contents of the microplate wells of COU 9 were inoculated intraperitoneally (IP) into female Swiss mice at 7-8 weeks of age. This confirmed the larvicidal activity of this compound. These results show that COU 9 exhibited larvicidal activity against T. canis larvae, which, after exposure to the compound, were non-viable, and that COU 9 inhibited infection in a murine model. In addition, COU 9 did not exhibit cytotoxicity and presented adequate bioavailability in silico, similar to albendazole, an anthelmintic, which is the first choice for treatment of human toxocariasis, supporting the potential for future investigations and preclinical tests on COU 9.

Ultraviolet light C prototype device against Sporothrix brasiliensis as a potential physical method for surface disinfection.

Sporothrix brasiliensis is recognized as an emergent fungal pathogen and the high amount of fungal propagules in the lesions of infected cats allows the contamination of surfaces by direct contact. Given that the environment can play a role in the transmission of this fungus, effective methods to eliminate this pathogen from contaminated surfaces are necessary. Physical methods, such as ultraviolet light C (UVC), are broad used for surfaces disinfection, however, non-data about its activity against S. brasiliensis is reported. Therefore, we aimed to evaluate an easy handled prototype of a UVC device, in the inhibition of S. brasiliensis. Three doses and times of exposure of irradiance were tested: 3.5 mJ/cm2 (1 s), 5.25 mJ/cm2 (1.5 s) and 329 mJ/cm2 (94 s) against a standardized inoculum of yeast and mold phase of S. brasiliensis. A decrease in CFU was shown in all doses of irradiance in both phases of S. brasiliensis, the average reduction ranged from 78 to 100% among doses, being a complete fungicidal activity achieved against the yeast phase after the 94 s exposure (329 mJ/cm2). Our data shows that UVC is a potential physical method for disinfection of surfaces contaminated with S. brasiliensis, and the prototype device developed provides an easy handling, and quickly results.

Highly effective decontamination in a hospital environment: An easy-to-operate, low-cost prototype.

Healthcare-associated infections (HAI) are illnesses acquired during healthcare and are often the most important adverse event during healthcare. With the aim of increasing the effectiveness of disinfection/decontamination processes in the health service with safe and not promote microbial resistance, we propose the development of portable equipment associated with type C ultraviolet light (UVC). The efficiency of the irradiance emitted by the equipment (at dosages 3.5, 5.0, and 60 mJ/cm2) was determined by the action exerted after exposure against four different bacterial (Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) and three different fungi (Candida albicans, C. parapsilosis, and Aspergillus section Fumigati). It was possible to observe that all treatments were capable of inactivating the bacterial species evaluated (p < 0.05), causing the irreversible death of these microorganisms. The most effective elimination of fungal agents was at a dose of 60 mJ/cm2 of UVC radiation, with a decrease in the fungal inoculum varying between 94% and 100% in relation to the control without exposure. Thus, our study showed that the application of the portable prototype with UVC light (254 nm) at a distance of 48 mm, allowed an average irradiance of 3.5 mW/cm2, with doses of 3.5 ≈ 60 mJ/cm2 (from 1 to 60 s of exposure), which can promote the total reduction of the bacteria evaluated and significantly reduce fungal growth. Therefore, this prototype could be used safely and effectively in the hospital environment, considerably reducing contamination and contributing to the reduction of healthcare-associated infection risk.

Toward a Platform for the Treatment of Burns: An Assessment of Nanoemulsions vs. Nanostructured Lipid Carriers Loaded with Curcumin.

Curcumin is a highly promising substance for treating burns, owing to its anti-inflammatory, antioxidant, antimicrobial, and wound-healing properties. However, its therapeutic use is restricted due to its hydrophobic nature and low bioavailability. This study was conducted to address these limitations; it developed and tested two types of lipid nanocarriers, namely nanoemulsions (NE-CUR) and nanostructured lipid carriers (NLC-CUR) loaded with curcumin, and aimed to identify the most suitable nanocarrier for skin burn treatment. The study evaluated various parameters, including physicochemical characteristics, stability, encapsulation efficiency, release, skin permeation, retention, cell viability, and antimicrobial activity. The results showed that both nanocarriers showed adequate size (~200 nm), polydispersity index (~0.25), and zeta potential (~>-20 mV). They also showed good encapsulation efficiency (>90%) and remained stable for 120 days at different temperatures. In the release test, NE-CUR and NCL-CUR released 57.14% and 51.64% of curcumin, respectively, in 72 h. NE-CUR demonstrated better cutaneous permeation/retention in intact or scalded skin epidermis and dermis than NLC-CUR. The cell viability test showed no toxicity after treatment with NE-CUR and NLC-CUR up to 125 µg/mL. Regarding microbial activity assays, free curcumin has activity against P. aeruginosa, reducing bacterial growth by 75% in 3 h. NE-CUR inhibited bacterial growth by 65% after 24 h, and the association with gentamicin had favorable results, while NLC-CUR showed a lower inhibition. The results demonstrated that NE-CUR is probably the most promising nanocarrier for treating burns.

Application of 1H HR-MAS NMR-Based Metabolite Fingerprinting of Marine Microalgae.

Natural products from the marine environment as well as microalgae, have been known for the complexity of the metabolites they produce due to their adaptability to different environmental conditions, which has been an inexhaustible source of several bioactive properties, such as antioxidant, anti-tumor, and antimicrobial. This study aims to characterize the main metabolites of three species of microalgae (Nannochloropsis oceanica, Chaetoceros muelleri, and Conticribra weissflogii), which have important applications in the biofuel and nutrition industries, by 1H High-resolution magic angle spinning nuclear magnetic resonance (1H HR-MAS NMR), a method which is non-destructive, is highly reproducible, and requires minimal sample preparation. Even though the three species were found in the same ecosystem and a superior production of lipid compounds was observed, important differences were identified in relation to the production of specialized metabolites. These distinct properties favor the use of these compounds as leaders in the development of new bioactive compounds, especially against environmental, human, and animal pathogens (One Health), and demonstrate their potential in the development of alternatives for aquaculture.

Pesquisa e desenvolvimento de nanomedicamentos: olhar bioético / Nanodrug research and development: a bioethical approach / Investigación y desarrollo de nanomedicinas: desde la mirada bioética

Resumo Nanotecnologia é a utilização de materiais na escala nanométrica, em que estes adquirem características próprias. A área de pesquisa e desenvolvimento de novos nanomedicamentos é uma das mais promissoras atualmente, todavia essas partículas necessitam de avaliação particular e ainda não há consenso referente às testagens específicas a serem seguidas, o que dificulta a formação de uma legislação que garanta a segurança e eficácia destes medicamentos, além de um processo de registro mais eficaz. Assim, é necessária uma abordagem bioética da nanotecnologia e sua utilização em medicamentos, visando garantir que o progresso científico não acarrete impactos irreversíveis. Diante dessa problemática, busca-se promover uma discussão nanoética referente ao processo de pesquisa e desenvolvimento de nanomedicamentos, por meio de estudo qualitativo, exploratório-descritivo e de caráter analítico, utilizando revisão bibliográfica, análise documental e dados quantitativos disponíveis como técnicas de pesquisa.

Abstract Nanotechnology consist of using materials at the nanoscale, in which they acquire specific characteristics. Nanodrug research and development is one of the most promising fields today; however, these particles require particular evaluation. Moreover, studies lack consensus on which specific tests to follow, thus hindering the elaboration of legislation that ensure their safety and efficacy, as well as a more effective registration process. Thus, a bioethical approach to nanotechnology and its use in drug development is necessary to ensure scientific progress without irreversible impacts. Given this scenario, this article proposes a nanoethics discussion regarding nanodrug research and development by means of a qualitative, exploratory and descriptive analysis, based on literature review, documental analysis and quantitative data available.

Resumen La nanotecnología utiliza materiales nanométricos, en que estos adquieren características propias. El área de investigación y desarrollo de nuevas nanomedicinas es una de las más prometedoras en la actualidad, sin embargo, estas partículas requieren de una evaluación particular y aún no existe consenso en cuanto a las pruebas específicas que seguir, lo que dificulta establecer una legislación que garantice la seguridad y eficacia de estos medicamentos, además de un proceso de registro más efectivo. Por lo tanto, se necesita un enfoque bioético de la nanotecnología y su uso en medicamentos para garantizar que el avance científico no tenga impactos irreversibles. Ante esta problemática, se pretende promover el debate sobre la nanoética en el proceso de investigación y desarrollo de nanomedicinas a partir de un estudio cualitativo, exploratorio-descriptivo y analítico, que utiliza como técnicas de investigación la revisión bibliográfica, el análisis de documentos y los datos cuantitativos disponibles.

Anti-Aspergillus fumigatus IgG in patients with bronchiectasis and its relationship with clinical outcome.

Aspergillosis is a mycosis, most commonly affecting the airways. This mycosis can worsen the clinical condition of patients with concurrent lung diseases. We assayed for the presence of serum anti-A. fumigatus IgG in bronchiectasis patients from a tertiary hospital in south Brazil and evaluated the relationship with clinical outcome. Thirty-one patients with bronchiectasis, without cystic fibrosis, were included. Clinical and epidemiological data were collected from all participants. Positive serological tests were detected in 13% (4/31) of the patients. The mortality rate for the year following the assay was, in the seropositive group, 75% (3/4), whereas in the seronegative group, 15% (4/27). An illustrative case is also shown and discussed. Our study highlights the diagnostic challenge and the possible impact of Aspergillus infection on these patients, indicating the necessity of more and larger investigations in the field.

Mutagenic damage among bronchiectasis patients attending in the pulmonology sector of a hospital in southern Brazil.

OBJECTIVE: Bronchiectasis is a chronic respiratory disease characterized by inflammation, irreversible dilation of the bronchi, and recurrent pulmonary infections, with a high morbidity and mortality rate, but is less studied from the point of view of its prevalence and associated factors not directly related to respiratory prognosis. As it is a disease related to the exacerbation of the inflammatory process and oxidative stress, this study searched to investigate the micronucleus frequency in patients with and without bronchiectasis treated at a specialized pulmonology service in a hospital in the extreme south of Brazil. METHODS: Patients with a confirmed tomographic diagnosis of bronchiectasis were defined as cases. Mutagenicity was evaluated by the micronucleus test in patients' oral mucosa cells. Data collection was performed through a questionnaire containing socioeconomic, demographic, lifestyle, and health condition information. RESULTS: Of the 95 patients involved in this study, 21 (22.1%) were diagnosed with bronchiectasis aged between 12 and 89 years. There was no significant difference in the frequency of micronucleus between patients with and without bronchiectasis. There was a significant positive association between age and frequency of micronucleus among patients with bronchiectasis, but this association does not occur among patients without the disease. CONCLUSION: This is the first study to investigate data on the prevalence and clinical and epidemiological aspects of this chronic disease in Brazil, especially those related to the genotoxicity outcome.

Development of a Novel Lipid-Based Nanosystem Functionalized with WGA for Enhanced Intracellular Drug Delivery.

Despite a considerable number of new antibiotics under going clinical trials, treatment of intracellular pathogens still represents a major pharmaceutical challenge. The use of lipid nanocarriers provides several advantages such as protection from compound degradation, increased bioavailability, and controlled and targeted drug release. Wheat germ agglutinin (WGA) is known to have its receptors on the alveolar epithelium and increase phagocytosis. The present study aimed to produce nanostructured lipid carriers with novel glycosylated amphiphilic employed to attach WGA on the surface of the nanocarriers to improve intracellular drug delivery. High-pressure homogenization was employed to prepare the lipid nanocarriers. In vitro, high-content analysis and flow cytometry assay was employed to study the increased uptake by macrophages when the nanocarriers were grafted with WGA. A lipid nanocarrier with surface-functionalized WGA protein (~200 nm, PDI > 0.3) was successfully produced and characterized. The system was loaded with a lipophilic model compound (quercetin; QU), demonstrating the ability to encapsulate a high amount of compound and release it in a controlled manner. The nanocarrier surface functionalization with the WGA protein increased the phagocytosis by macrophages. The system proposed here has characteristics to be further explored to treat intracellular pathogens.

Intramacrophage potential of a tetrahydropyridine: A promising compound in combating Mycobacterium tuberculosis.

Due to several obstacles in treating tuberculosis (TB), the search for new therapeutic alternatives remains a global priority. The nitrogenous heterocyclic compounds are promising in searching for new anti-Mycobacterium tuberculosis molecules, and our previous results highlight the potential of tetrahydropyridines. After exploring the antimycobacterial potential and putative mechanism of action of a tetrahydropyridine derivative (NUNL02), we seek to measure the oxidative stress caused by NUNL02 inside the extracellular replicating M. tuberculosis since it could be the reason for the NUNL02 bactericidal effect against replicating and starved M. tuberculosis; and to evaluate the anti-M. tuberculosis activity of NUNL02 against the intracellular bacillus (even combined with an anti-TB drug) to explore the potential of this tetrahydropyridine as a promising adjuvant for TB therapy. Briefly, we assessed the activity of NUNL02 against the H37Rv strain and evaluated the combination of NUNL02 and rifampicin (RIF), at previously defined subinhibitory concentrations, against intramacrophage M. tuberculosis. NUNL02, in addition to promote the oxidative stress inside the extracellular replicating M. tuberculosis as a possible indirect mechanism of action, also presented bactericidal potential as promising as RIF against intracellular bacilli. Thus, our findings reinforce NUNL02 as a promising scaffold for the development of new options for TB.

Mutagenic damage among bronchiectasis patients attending in the pulmonology sector of a hospital in southern Brazil

SUMMARY OBJECTIVE: Bronchiectasis is a chronic respiratory disease characterized by inflammation, irreversible dilation of the bronchi, and recurrent pulmonary infections, with a high morbidity and mortality rate, but is less studied from the point of view of its prevalence and associated factors not directly related to respiratory prognosis. As it is a disease related to the exacerbation of the inflammatory process and oxidative stress, this study searched to investigate the micronucleus frequency in patients with and without bronchiectasis treated at a specialized pulmonology service in a hospital in the extreme south of Brazil. METHODS: Patients with a confirmed tomographic diagnosis of bronchiectasis were defined as cases. Mutagenicity was evaluated by the micronucleus test in patients' oral mucosa cells. Data collection was performed through a questionnaire containing socioeconomic, demographic, lifestyle, and health condition information. RESULTS: Of the 95 patients involved in this study, 21 (22.1%) were diagnosed with bronchiectasis aged between 12 and 89 years. There was no significant difference in the frequency of micronucleus between patients with and without bronchiectasis. There was a significant positive association between age and frequency of micronucleus among patients with bronchiectasis, but this association does not occur among patients without the disease. CONCLUSION: This is the first study to investigate data on the prevalence and clinical and epidemiological aspects of this chronic disease in Brazil, especially those related to the genotoxicity outcome.

Thesis and dissertations examining tuberculosis in Brazil between 2013 and 2019: an overview.

BACKGROUND: Tuberculosis (TB) remains a serious public health problem, with approximately 10 million new cases reported annually. Knowledge about the quantitative evolution of theses and dissertations (T&Ds) examining human TB in Brazil can contribute to generating strategic planning for training professionals in this field and disease control. Therefore, this study highlights the role of T&Ds on TB in national scientific disclosures. METHODS: An integrative review related to TB was performed, including T&Ds produced in Brazil and completed between 2013 and 2019. RESULTS: A total of 559,457 T&Ds were produced, of which 1,342 were associated with TB, accounting for 0.24% of the total number of T&Ds in Brazil. This was evidenced by a predominance of themes such as attention/health care, epidemiology, and TB treatment, and 80.2% of the T&Ds on TB were related to the large areas of health and biological sciences. Only 19.7% of T&Ds were associated with groups of patients considered at risk for TB, and 50.9% were produced in southeastern Brazil. The 1,342 T&Ds on TB were developed in 416 postgraduate programs linked to 121 higher education institutions (HEIs). We highlight that 72.7% of T&Ds on TB were produced in federal HEIs, 27.4% in state HEIs, and 8.5% in private HEIs. CONCLUSIONS: Strategic themes, such as TB control, require public policies that aim to increase the number of doctors and masters with expertise in TB, with geographic uniformity, and in line with the priorities for disease control.

Charge effect of water-soluble porphyrin derivatives as a prototype to fight infections caused by Acinetobacter baumannii by aPDT approaches.

In the last decade, Acinetobacter baumannii has emerged as a pathogen associated with infections in intensive care units worldwide, especially due to its ability to resist an extensive list of antibiotics. In this context, porphyrins have emerged as an important strategy in photodynamic therapy, since they are a group of tetrapyrrolic compounds with important photochemical and photobiological activities. In this study, the antimicrobial photodynamic activity of meso-tetra(4-N-methyl-pyridyl)porphyrin (H2TMePyP+) and meso-tetra(4-sulfonatophenyl)porphyrin (H2TPPS‒) was evaluated against A. baumannii by minimum inhibitory concentration (MIC), anti-biofilm activity, and the interaction with antibiotics after exposure to white-light LED irradiation. The cationic derivative H2TMePyP+ was more potent (MIC = 0.61 µM) than H2TPPS‒, with anti-biofilm activity and increased the antimicrobial activity of ciprofloxacin and amikacin. Given these findings, the tetra-cationic porphyrins can be assumed as prototypes to optimize and develop new agents by promoting oxidative stress and inducing free radical production.

Chemical Profile and Antimicrobial Activity of the Marine Diatom Chaetoceros muelleri.

Microalgae, due to its rapid growth, low nutritional requirements, and versatility of adaptation to different environmental conditions, has aroused the biotechnological interest, synthesizing novel molecules with antioxidant, anticoagulant, anti-inflammatory, antitumor, and antimicrobial activities. In this sense, we carried out the bioprospection of Chaetoceros muelleri, a marine diatom employed in aquaculture, as a candidate to the development of new drugs for the treatment of bacterial infections. The chemical profile of extracts in different solvents (hexane, chloroform, methylene chloride, ethyl acetate, methanol, and acetone) were analyzed by 1 H-NMR. The hexane extract was the most active against all bacteria species tested, including Mycobacterium tuberculosis, with a minimum inhibitory concentration of 100 µg/ml. Contrarily, the methanol extract was inactive against all tested microorganisms and, in addition, was the only one with IC50 >800 µg/mL, showing no cytotoxicity in VERO cell lines. All other extracts showed antibacterial potential and IC50 values varying between 267.58 and 142.47 µg/ml. The fact that C. muelleri is a microalga easily grown on bioreactors on a large scale may promote its biotechnological use, especially as scaffolds for the development of new compounds against bacterial species of clinical and public health interest.

Mushroom extract of Lactarius deliciosus (L.) Sf. Gray as biopesticide: Antifungal activity and toxicological analysis.

Monilinia fructicola (Wint.) Honey is a plant pathogenic fungus that infects stone fruits such as peach, nectarine and plum, which are high demand cultivars found in Brazil. This pathogen may remain latent in the host, showing no apparent signs of disease, and consequently may spread to different countries. The aim of this study was to evaluate the activity of hydroalcoholic extract (HydE) obtained from Lactarius deliciosus (L.) Sf. Gray a mushroom, against M. fructicola phytopathogenic-induced mycelial growth. In addition, the purpose of this study was to examine phytotoxicity attributed to HydE using Brassica oleracea seeds, as well as cytotoxic analysis of this extract on cells of mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) (ATCC TIB-67). The L. deliciosus HydE inhibited fungal growth and reduced phytopathogen mycelial development at a concentration of 1.25 mg/ml. Our results demonstrated that the extract exhibited phytotoxicity as evidenced by (1) interference on germination percentage and rate index, (2) decreased root and initial growth measures, and (3) lower fresh weight of seedlings but no cytotoxicity in Vero cell lines. Data suggest that the use of the L. deliciosus extracts may be beneficial for fungal control without any apparent adverse actions on mouse BALB/c monocyte macrophage cell line (J774A.1 cell line) viability.

Thesis and dissertations examining tuberculosis in Brazil between 2013 and 2019: an overview

ABSTRACT Background: Tuberculosis (TB) remains a serious public health problem, with approximately 10 million new cases reported annually. Knowledge about the quantitative evolution of theses and dissertations (T&Ds) examining human TB in Brazil can contribute to generating strategic planning for training professionals in this field and disease control. Therefore, this study highlights the role of T&Ds on TB in national scientific disclosures. Methods: An integrative review related to TB was performed, including T&Ds produced in Brazil and completed between 2013 and 2019. Results: A total of 559,457 T&Ds were produced, of which 1,342 were associated with TB, accounting for 0.24% of the total number of T&Ds in Brazil. This was evidenced by a predominance of themes such as attention/health care, epidemiology, and TB treatment, and 80.2% of the T&Ds on TB were related to the large areas of health and biological sciences. Only 19.7% of T&Ds were associated with groups of patients considered at risk for TB, and 50.9% were produced in southeastern Brazil. The 1,342 T&Ds on TB were developed in 416 postgraduate programs linked to 121 higher education institutions (HEIs). We highlight that 72.7% of T&Ds on TB were produced in federal HEIs, 27.4% in state HEIs, and 8.5% in private HEIs. Conclusions: Strategic themes, such as TB control, require public policies that aim to increase the number of doctors and masters with expertise in TB, with geographic uniformity, and in line with the priorities for disease control.

In vitro susceptibility of Sporothrix spp. to complexes coordinated with Co(II) and cobalt chloride hexahydrate

Abstract Sporothrix spp. are the major dimorphic fungus associated with a type of subcutaneous mycosis, sporotrichosis. The limitation of antifungal availability and the past reports of in vitro resistance of Sporothrix spp. clinical isolates makes it important to search for new compounds with antifungal activities. In this study, we therefore evaluate the in vitro activities of complexes coordinated with Co(II) and cobalt chloride hexahydrate against clinical isolates of Sporothrix spp. Broth microdilution test was performed as per M38-A2 from CLSI (2008) in duplicate for 31 clinical isolates of Sporothrix spp. (27 S. brasiliensis e 04 S. schenckii stricto sensu). The antifungal activities of the complexes coordinated with Co(II) and cobalt chloride hexahydrate were detected at a concentration range of 32-128 µg/mL for all isolates. None of the compounds demonstrated any cytotoxicity (to macrophage cells) at the concentration of 200 µg/mL. The activity against Sporothrix spp. recorded in this study instigate the continuity of experimental studies with Co(II) to search for the mechanisms of antifungal action as well as to evaluate its interaction with the commercial antifungal drugs.