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1.
Int Microbiol ; 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38236380

RESUMO

The increase in global travel and the incorrect and excessive use of antibiotics has led to an unprecedented rise in antibiotic resistance in bacterial and fungal populations. To overcome these problems, novel bioactive natural products must be discovered, which may be found in underexplored environments, such as estuarine habitats. In the present work, estuarine actinomycetotal strains were isolated with conventional and iChip techniques from the Tagus estuary in Alcochete, Portugal, and analysed for different antimicrobial bioactivities. Extracts were produced from the isolated cultures and tested for bioactivity against Staphylococcus aureus ATCC 29213, Escherichia coli ATCC 25922, Aspergillus fumigatus ATCC 240305, Candida albicans ATCC 10231 and Trichophyton rubrum FF5. Furthermore, bioactive extracts were subjected to dereplication by high-performance liquid chromatography (HPLC) and high-resolution mass spectrometry (HRMS) to putatively identify their chemical components. In total, 105 isolates belonging to 3 genera were obtained. One which was isolated, MTZ3.1 T, represents a described novel taxon for which the name Streptomyces meridianus was proposed. Regarding the bioactivity testing, extracts from 12 strains proved to be active against S. aureus, 2 against E. coli, 4 against A. fumigatus, 3 against C. albicans and 10 against T. rubrum. Dereplication of bioactive extracts showed the presence of 28 known bioactive molecules, 35 hits have one or more possible matches in the DNP and 18 undescribed ones. These results showed that the isolated bacteria might be the source of new bioactive natural products.

2.
Antonie Van Leeuwenhoek ; 117(1): 26, 2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38261060

RESUMO

An appealing strategy for finding novel bioactive molecules in Nature consists in exploring underrepresented and -studied microorganisms. Here, we investigated the antimicrobial and tumoral anti-proliferative bioactivities of twenty-three marine and estuarine bacteria of the fascinating phylum Planctomycetota. This was achieved through extraction of compounds produced by the Planctomycetota cultured in oligotrophic medium followed by an antimicrobial screening against ten relevant human pathogens including Gram-positive and Gram-negative bacteria, and fungi. Cytotoxic effects of the extracts were also evaluated against five tumoral cell lines. Moderate to potent activities were obtained against Enterococcus faecalis, methicillin-sensitive and methicillin-resistant Staphylococcus aureus and vancomycin-sensitive and vancomycin-resistant Enterococcus faecium. Anti-fungal effects were observed against Trichophyton rubrum, Candida albicans and Aspergillus fumigatus. The highest cytotoxic effects were observed against human breast, pancreas and melanoma tumoral cell lines. Novipirellula caenicola and Rhodopirellula spp. strains displayed the widest spectrum of bioactivities while Rubinisphaera margarita ICM_H10T affected all Gram-positive bacteria tested. LC-HRMS analysis of the extracts did not reveal the presence of any known bioactive natural product, suggesting that the observed activities are most likely caused by novel molecules, that need identification. In summary, we expanded the scope of planctomycetal species investigated for bioactivities and demonstrated that various strains are promising sources of novel bioactive compounds, which reenforces the potential biotechnological prospects offered by Planctomycetota.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Planctomicetos , Humanos , Bactérias Gram-Negativas , Antibacterianos/farmacologia , Vancomicina , Bactérias Gram-Positivas
3.
Int J Mol Sci ; 25(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38791254

RESUMO

Mycoses are one of the major causes of morbidity/mortality among immunocompromised individuals. Considering the importance of these infections, the World Health Organization (WHO) defined a priority list of fungi for health in 2022 that include Candida albicans as belonging to the critical priority group and Pichia kudriavzevii (Candida krusei) to the medium priority group. The existence of few available antifungal drugs, their high toxicity, the acquired fungal resistance, and the appearance of new species with a broader spectrum of resistance, points out the need for searching for new antifungals, preferably with new and multiple mechanisms of action. The cyclam salt H4[H2(4-CF3PhCH2)2Cyclam]Cl4 was previously tested against several fungi and revealed an interesting activity, with minimal inhibitory concentration (MIC) values of 8 µg/mL for C. krusei and of 128 µg/mL for C. albicans. The main objective of the present work was to deeply understand the mechanisms involved in its antifungal activity. The effects of the cyclam salt on yeast metabolic viability (resazurin reduction assay), yeast mitochondrial function (JC-1 probe), production of reactive oxygen species (DCFH-DA probe) and on intracellular ATP levels (luciferin/luciferase assay) were evaluated. H4[H2(4-CF3PhCH2)2Cyclam]Cl4 induced a significant decrease in the metabolic activity of both C. albicans and C. krusei, an increase in Reactive Oxygen Species (ROS) production, and an impaired mitochondrial function. The latter was observed by the depolarization of the mitochondrial membrane and decrease in ATP intracellular levels, mechanisms that seems to be involved in the antifungal activity of H4[H2(4-CF3PhCH2)2Cyclam]Cl4. The interference of the cyclam salt with human cells revealed a CC50 value against HEK-293 embryonic kidney cells of 1.1 µg/mL and a HC10 value against human red blood cells of 0.8 µg/mL.


Assuntos
Antifúngicos , Candida albicans , Candida , Testes de Sensibilidade Microbiana , Espécies Reativas de Oxigênio , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Humanos , Espécies Reativas de Oxigênio/metabolismo , Candida/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pichia
4.
Oncology ; 101(5): 292-302, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36657399

RESUMO

BACKGROUND: Malignant primary cardiac tumors are exceedingly rare, and despite surgical exeresis or chemotherapy, their prognosis remains poor. Cardiac invasion by metastatic tumors, while more common, also entails an unsatisfactory outcome. This study aimed to review patients diagnosed with malignant primary and secondary cardiac tumors in a tertiary center between 1995 and 2022. METHODS: Clinical data, echocardiographic, computed tomography, and magnetic resonance assessments of tumor location and morphology, histology, treatment, and survival were retrospectively analyzed. RESULTS: Sixty malignant cardiac tumors were diagnosed: 17 primary (A) and 43 metastatic (B) tumors. A: the most common types were angiosarcoma (41%), undifferentiated sarcoma (23%), and fibrosarcoma (18%). Patients with primary tumors were younger than patients with metastatic tumors (41 ± 13 years vs. 57 ± 18 years, p = 0.001), with no significant gender difference. The most frequent presentations were heart failure (59%) and arrhythmia (23%). The most prevalent tumor location was the right heart chambers (71%), mostly in the right atrium (35%). 47% were submitted to tumor resection, and 29% received chemotherapy. The mortality rate was 82% with a median survival of 6.0 (interquartile range: 1.0-11.8) months after diagnosis (minimum of 12 days and maximum of 19 years). One patient with fibrosarcoma underwent heart transplantation and was still alive and well after 19 years. B: regarding metastatic cardiac invasion, the most common primary tumor sites were lung carcinomas (38%), thymomas (17%), and lymphomas (14%). Presentation with pericardial effusion was common (33%). The mortality rate was 72%, with a median survival of 3.6 (1.0-13.4) months (minimum of 7 days, maximum of 5 years). CONCLUSION: Diagnosis of metastatic cardiac tumors was more common than that of malignant primary tumors, both with a dismal prognosis. When radical exeresis is not possible, heart transplantation can be an option with a favorable outcome in carefully selected patients with sarcomas.


Assuntos
Fibrossarcoma , Neoplasias Cardíacas , Hemangiossarcoma , Sarcoma , Humanos , Estudos Retrospectivos , Hemangiossarcoma/patologia , Hemangiossarcoma/cirurgia , Sarcoma/diagnóstico , Neoplasias Cardíacas/cirurgia , Neoplasias Cardíacas/diagnóstico
5.
Crit Rev Food Sci Nutr ; 63(12): 1707-1721, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34486889

RESUMO

A proper nutrition is crucial for children's healthy development. Regardless of the usual recommendations to follow a varied diet, some foods can be a source of toxic natural contaminants such as mycotoxins, potent secondary metabolites produced by filamentous fungi. In addition to the most well-known mycotoxins, many of which are subject to tight regulation regarding the maximum levels allowed in different types of food, there is a large group of mycotoxins, the so-called emerging mycotoxins, about which less knowledge has already been acquired, which have gradually been the target of interest from the scientific community due to their prevalence in most foodstuffs, particularly in cereals and cereal-based products. Alternariol and his metabolite alternariol mono-methyl ether, beauvericin, citrinin, culmorin, enniatins, ergot alkaloids, fusaproliferin, kojic acid, moniliformin, sterigmatocystin, tentoxin and tenuazonic acid are the most representative of them. The current review gathered the information of the last ten years that have been published on the levels of emerging mycotoxins in food products dedicated for infants and children. European Union countries are responsible for most of the reported studies, which showed levels that can reach hundreds of mg/kg.


Assuntos
Micotoxinas , Criança , Lactente , Humanos , Micotoxinas/análise , Contaminação de Alimentos/análise , Lactonas , Fungos/metabolismo , Grão Comestível/química
6.
Mar Drugs ; 21(12)2023 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-38132930

RESUMO

Parasitic diseases still compromise human health. Some of the currently available therapeutic drugs have limitations considering their adverse effects, questionable efficacy, and long treatment, which have encouraged drug resistance. There is an urgent need to find new, safe, effective, and affordable antiparasitic drugs. Marine-derived cyclic peptides have been increasingly screened as candidates for developing new drugs. Therefore, in this review, a systematic analysis of the scientific literature was performed and 25 marine-derived cyclic peptides with antiparasitic activity (1-25) were found. Antimalarial activity is the most reported (51%), followed by antileishmanial (27%) and antitrypanosomal (20%) activities. Some compounds showed promising antiparasitic activity at the nM scale, being active against various parasites. The mechanisms of action and targets for some of the compounds have been investigated, revealing different strategies against parasites.


Assuntos
Antiprotozoários , Leishmaniose , Doenças Parasitárias , Humanos , Antiparasitários/química , Peptídeos Cíclicos/farmacologia , Peptídeos Cíclicos/uso terapêutico , Leishmaniose/tratamento farmacológico , Antiprotozoários/química , Doenças Parasitárias/tratamento farmacológico
7.
Mar Drugs ; 21(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-37999375

RESUMO

Natural products are a very rich source for obtaining new compounds with therapeutic potential. In the search for new antiparasitic and antimicrobial agents, molecular hybrids were designed based on the structures of antimicrobial marine quinazolinones and eugenol, a natural phenolic compound. Following reports of the therapeutic potential of quinazolinones and eugenol derivatives, it was expected that the union of these pharmacophores could generate biologically relevant substances. The designed compounds were obtained by classical synthetic procedures and were characterized by routine spectrometric techniques. Nine intermediates and final products were then evaluated in vitro against Trypanosoma brucei and Leishmania infantum. Antifungal and antibacterial activity were also evaluated. Six compounds (9b, 9c, 9d, 10b, 10c, and 14) showed mild activity against T. brucei with IC50 in the range of 11.17-31.68 µM. Additionally, intermediate 9c showed anti-Leishmania activity (IC50 7.54 µM) and was six times less cytotoxic against THP-1 cells. In conclusion, novel derivatives with a simple quinazolinone scaffold showing selectivity against parasites without antibacterial and antifungal activities were disclosed, paving the way for new antitrypanosomal agents.


Assuntos
Anti-Infecciosos , Antiprotozoários , Leishmania infantum , Trypanosoma brucei brucei , Antifúngicos/farmacologia , Eugenol , Antiprotozoários/química , Antibacterianos/farmacologia , Quinazolinonas/química , Relação Estrutura-Atividade
8.
Int J Mol Sci ; 24(2)2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36674962

RESUMO

Yeast acquisition begins at birth; however, the contribution of the mother on yeast transmission to the offspring and associated resistance is yet to be clarified. The aim of this study was to explore the vertical transmission of yeasts and their antifungal susceptibility profile in early life. Oral, fecal, and breastmilk samples were collected from 73 mother-child pairs four to twelve weeks after delivery and cultured on Sabouraud dextrose agar with chloramphenicol. The isolates were identified by MALDI-TOF MS. The vertical transmission was studied by microsatellite genotyping. Antifungal susceptibility was determined for fluconazole, voriconazole, miconazole, anidulafungin, and nystatin by broth microdilution assay, following CLSI-M60 guidelines. A total of 129 isolates were identified from 53% mother-child pairs. We verified the vertical transmission of Candida albicans (n = three mother-child pairs) and Candida parapsilosis (n = one mother-child pair) strains, including an antifungal resistant strain transmitted from breastmilk to the gut of a child. Most isolates were susceptible to the tested antifungals, with the exception of four C. albicans isolates and one R. mucilaginosa isolate. The vertical transmission of yeasts happens in early life. This is the first work that demonstrated the role of the mother as a source of transmission of antifungal-resistant yeasts to the child.


Assuntos
Antifúngicos , Leite Humano , Recém-Nascido , Humanos , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Candida , Leveduras , Boca , Relações Mãe-Filho , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica
9.
Molecules ; 28(7)2023 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-37049958

RESUMO

The purpose of this work was to investigate, for the first time to our knowledge, the chemical composition and bioactivity of methanolic extracts (roots, stems, leaves, and flowers) from Cladanthus mixtus (L.) Chevall. that grows wild in northern Morocco (the Tangier-Tetouan-Al Hoceima region). The phenolic and flavonoid contents were determined by spectrophotometer methods, and the composition of derivatized methanolic extracts from C. mixtus using N-O-bis(trimethylsilyl) trifluoroacetamide (BSTFA) was analyzed by gas chromatography-mass spectrometry (GC-MS). The antioxidant activity was carried out by applying the 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and DPPH (2,2-diphenyl-1-picrylhydrazyl) tests. The micro-dilution technique was chosen to investigate the antimicrobial activity of methanolic extracts against two bacterial strains and three fungal species. The results showed that the values of total phenolic and flavonoid contents were found to be higher in flower extracts (30.55 ± 0.85 mg of gallic acid equivalents (GAE)/g of dried weight (DW) and 26.00 ±1.34 mg of quercetin equivalents (QE)/g DW, respectively). Other groups of chemical compounds were revealed by GC-MS, such as carbohydrates (27.25-64.87%), fatty acids (1.58-9.08%), organic acids (11.81-18.82%), and amino acids (1.26-7.10%). Root and flower methanolic extracts showed the highest antioxidant activity using ABTS (39.49 mg of Trolox equivalents (TE)/g DW) and DPPH (36.23 mg TE/g DW), respectively. A positive correlation between antioxidant activity and polyphenol and flavonoid amounts was found. Antibacterial tests showed that the best activity was presented by the leaf extract against Staphylococcus aureus (minimum inhibitory concentration (MIC) = minimum bactericidal concentration (MBC) = 20 mg/mL) and Escherichia coli (MIC of 30 mg/mL and MBC of 35 mg/mL). S. aureus was more sensitive to the extracts compared to E. coli. All extracts showed antifungal activity against Trichophyton rubrum, with the best efficacy reported by the flower and leaf extracts (MIC = 1.25 mg/mL and minimum fungicidal concentration (MFC) = 2.5 mg/mL). In general, extracts of C. mixtus appeared less effective against Candida albicans and Aspergillus fumigatus.


Assuntos
Antioxidantes , Extratos Vegetais , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Antioxidantes/farmacologia , Antioxidantes/química , Staphylococcus aureus , Escherichia coli , Marrocos , Flavonoides/farmacologia , Flavonoides/análise , Fenóis/farmacologia , Fenóis/análise , Metanol/farmacologia
10.
Bioorg Med Chem Lett ; 67: 128743, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35447343

RESUMO

Antimicrobial resistance arises due to several adaptation mechanisms, being the overexpression of efflux pumps (EPs) one of the most worrisome. In bacteria, EPs can also play important roles in virulence, quorum-sensing (QS) and biofilm formation. To identify new potential antimicrobial adjuvants, a library of diarylpentanoids and chalcones was synthesized and tested. These compounds presented encouraging results in potentiating the activity of antimicrobials, being diarylpentanoid 13 the most promising. Compounds 9, 13, 16, 19, 22, and 23 displayed EP inhibitory effect, mainly in Staphylococcus aureus 272123. Compounds 13, 19, 22, and 23 exhibited inhibitory effect on biofilm formation in S. aureus 272,123 while 13 and 22 inhibited QS in the pair Sphingomonas paucimobilis Ezf 10-17 and Chromobacterium violaceum CV026. The overall results, demonstrated that diarylpentanoid 13 and chalcone 22 were active against all the resistance mechanisms tested, suggesting their potential as antimicrobial adjuvants.


Assuntos
Chalcona , Chalconas , Antibacterianos/farmacologia , Biofilmes , Chalcona/farmacologia , Chalconas/farmacologia , Chromobacterium , Percepção de Quorum , Staphylococcus aureus
11.
Mar Drugs ; 20(6)2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35736200

RESUMO

Oceans are a rich source of structurally unique bioactive compounds from the perspective of potential therapeutic agents. Marine peptides are a particularly interesting group of secondary metabolites because of their chemistry and wide range of biological activities. Among them, cyclic peptides exhibit a broad spectrum of antimicrobial activities, including against bacteria, protozoa, fungi, and viruses. Moreover, there are several examples of marine cyclic peptides revealing interesting antimicrobial activities against numerous drug-resistant bacteria and fungi, making these compounds a very promising resource in the search for novel antimicrobial agents to revert multidrug-resistance. This review summarizes 174 marine cyclic peptides with antibacterial, antifungal, antiparasitic, or antiviral properties. These natural products were categorized according to their sources-sponges, mollusks, crustaceans, crabs, marine bacteria, and fungi-and chemical structure-cyclic peptides and depsipeptides. The antimicrobial activities, including against drug-resistant microorganisms, unusual structural characteristics, and hits more advanced in (pre)clinical studies, are highlighted. Nocathiacins I-III (91-93), unnarmicins A (114) and C (115), sclerotides A (160) and B (161), and plitidepsin (174) can be highlighted considering not only their high antimicrobial potency in vitro, but also for their promising in vivo results. Marine cyclic peptides are also interesting models for molecular modifications and/or total synthesis to obtain more potent compounds, with improved properties and in higher quantity. Solid-phase Fmoc- and Boc-protection chemistry is the major synthetic strategy to obtain marine cyclic peptides with antimicrobial properties, and key examples are presented guiding microbiologist and medicinal chemists to the discovery of new antimicrobial drug candidates from marine sources.


Assuntos
Anti-Infecciosos , Produtos Biológicos , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Fungos/química , Peptídeos Cíclicos/química , Peptídeos Cíclicos/farmacologia
12.
Mar Drugs ; 20(5)2022 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-35621966

RESUMO

The growing number of infectious diseases around the world threatens the effective response of antibiotics, contributing to the increase in antibiotic resistance seen as a global health problem. Currently, one of the main challenges in antimicrobial drug discovery is the search for new compounds that not only exhibit antimicrobial activity, but can also potentiate the antimicrobial activity and revert antibiotics' resistance, through the interference with several mechanisms, including the inhibition of efflux pumps (EPs) and biofilm formation. Inspired by macroalgae brominated bromophenol BDDE with antimicrobial activity, a series of 18 chalcone derivatives, including seven chalcones (9-15), six dihydrochalcones (16-18, and 22-24) and five diarylpropanes (19-21, and 25 and 26), was prepared and evaluated for its antimicrobial activity and potential to fight antibiotic resistance. Among them, chalcones 13 and 14 showed promising antifungal activity against the dermatophyte clinical strain of Trichophyton rubrum, and all compounds reversed the resistance to vancomycin in Enterococcus faecalis B3/101, with 9, 14, and 24 able to cause a four-fold decrease in the MIC of vancomycin against this strain. Compounds 17-24 displayed inhibition of EPs and the formation of biofilm by S. aureus 272123, suggesting that these compounds are inhibiting the EPs responsible for the extrusion of molecules involved in biofilm-related mechanisms. Interestingly, compounds 17-24 did not show cytotoxicity in mouse embryonic fibroblast cell lines (NIH/3T3). Overall, the results obtained suggest the potential of dihydrochalcones 16-18 and 22-24, and diarylpropanes 19-21, 25 and 26, as hits for bacterial EPs inhibition, as they are effective in the inhibition of EPs, but present other features that are important in this matter, such as the lack of antibacterial activity and cytotoxicity.


Assuntos
Anti-Infecciosos , Chalcona , Chalconas , Micoses , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Chalcona/farmacologia , Chalconas/farmacologia , Fibroblastos , Camundongos , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Relação Estrutura-Atividade , Vancomicina/farmacologia
13.
Int J Mol Sci ; 23(22)2022 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-36430768

RESUMO

Resistance to antibiotics is an emerging problem worldwide, which leads to an increase in morbidity and mortality rates. Several mechanisms are attributed to bacterial resistance, overexpression of efflux pumps being one of the most prominent. As an attempt to develop new effective antimicrobial drugs, which could be able to act against resistant bacterial strains and considering the antimicrobial potential of flavonoids and triazolyl flavonoid derivatives, in particular chalcones, a small library of chalcone derivatives was synthesized and evaluated for its potential to act as antimicrobials and/or adjuvants in combination with antibiotics towards resistant bacteria. Although only compound 7 was able to act as antibacterial, compounds 1, 2, 4, 5, 7, and 9 revealed to be able to potentiate the activity of antibiotics in resistant bacteria. Moreover, five compounds (3, 5-8) demonstrated to be effective inhibitors of efflux pumps in Salmonella enterica serovar Typhimurium SL1344, and four compounds (1, 3, 7, and 10) showed higher ability than reserpine to inhibit biofilm formation of resistant Staphylococcus aureus 272123. Together, our results showed the potential of these compounds regarding reversion of bacterial resistance.


Assuntos
Anti-Infecciosos , Chalcona , Chalconas , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Humanos , Chalcona/farmacologia , Chalconas/farmacologia , Triazóis/farmacologia , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias , Salmonella typhimurium , Resistência a Múltiplos Medicamentos
14.
Int J Mol Sci ; 23(22)2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36430942

RESUMO

The overexpression of efflux pumps is one of the strategies used by bacteria to resist antibiotics and could be targeted to circumvent the antibiotic crisis. In this work, a series of trimethoxybenzoic acid derivatives previously described as antifouling compounds was explored for potential antimicrobial activity and efflux pump (EP) inhibition. First, docking studies on the acridine resistance proteins A and B coupled to the outer membrane channel TolC (AcrAB-TolC) efflux system and a homology model of the quinolone resistance protein NorA EP were performed on 11 potential bioactive trimethoxybenzoic acid and gallic acid derivatives. The synthesis of one new trimethoxybenzoic acid derivative (derivative 13) was accomplished. To investigate the potential of this series of 11 derivatives as antimicrobial agents, and in reverting drug resistance, the minimum inhibitory concentration was determined on several strains (bacteria and fungi), and synergy with antibiotics and EP inhibition were investigated. Derivative 10 showed antibacterial activity against the studied strains, derivatives 5 and 6 showed the ability to inhibit EPs in the acrA gene inactivated mutant Salmonella enterica serovar Typhimurium SL1344, and 6 also inhibited EPs in Staphylococcus aureus 272123. Structure-activity relationships highlighted trimethoxybenzoic acid as important for EP inhibitory activity. Although further studies are necessary, these results show the potential of simple trimethoxybenzoic acid derivatives as a source of feasible EP inhibitors.


Assuntos
Proteínas de Bactérias , Ácido Gálico , Ácido Gálico/farmacologia , Ácido Gálico/metabolismo , Proteínas de Bactérias/metabolismo , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Staphylococcus aureus/metabolismo
15.
Mar Drugs ; 19(12)2021 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-34940681

RESUMO

Marine biofouling is a natural process that represents major economic, environmental, and health concerns. Some booster biocides have been used in biofouling control, however, they were found to accumulate in environmental compartments, showing negative effects on marine organisms. Therefore, it is urgent to develop new eco-friendly alternatives. Phenyl ketones, such as benzophenones and acetophenones, have been described as modulators of several biological activities, including antifouling activity (AF). In this work, acetophenones were combined with other chemical substrates through a 1,2,3-triazole ring, a strategy commonly used in Medicinal Chemistry. In our approach, a library of 14 new acetophenone-triazole hybrids was obtained through the copper(I)-catalyzed alkyne-azide cycloaddition "click" reaction. All of the synthesized compounds were evaluated against the settlement of a representative macrofouling species, Mytilus galloprovincialis, as well as on biofilm-forming marine microorganisms, including bacteria and fungi. The growth of the microalgae Navicula sp. was also evaluated after exposure to the most promising compounds. While compounds 6a, 7a, and 9a caused significant inhibition of the settlement of mussel larvae, compounds 3b, 4b, and 7b were able to inhibit Roseobacter litoralis bacterial biofilm growth. Interestingly, acetophenone 7a displayed activity against both mussel larvae and the microalgae Navicula sp., suggesting a complementary action of this compound against macro- and microfouling species. The most potent compounds (6a, 7a, and 9a) also showed to be less toxic to the non-target species Artemia salina than the biocide Econea®. Regarding both AF potency and ecotoxicity activity evaluation, acetophenones 7a and 9a were put forward in this work as promising eco-friendly AF agents.


Assuntos
Acetofenonas/farmacologia , Incrustação Biológica/prevenção & controle , Desinfetantes/farmacologia , Triazóis/farmacologia , Acetofenonas/química , Animais , Organismos Aquáticos , Biofilmes/efeitos dos fármacos , Bivalves/efeitos dos fármacos , Desinfetantes/química , Larva/efeitos dos fármacos , Microalgas/efeitos dos fármacos , Relação Estrutura-Atividade , Triazóis/química
16.
Med Mycol ; 58(4): 564-567, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-31509195

RESUMO

The continuous emergence of Candida strains resistant to currently used antifungals demands the development of new alternatives that could reduce the burden of candidiasis. In this work silver nanoparticles synthesized using a green route are efficiently used, alone or in combination with fluconazole, amphotericin B or nystatine, to inhibit growth of C. albicans and C. glabrata oral clinical strains, including in strains showing resistance to fluconazole. A potent inhibitory effect over biofilm formation prompted by the two Candida species was also observed, including in mature biofilm cells. These results foster the use of phytotherapeutics as effective treatments in oral candidiasis.


Assuntos
Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/efeitos dos fármacos , Candida glabrata/efeitos dos fármacos , Nanopartículas Metálicas/química , Polienos/farmacologia , Punica granatum/química , Anfotericina B/farmacologia , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Fluconazol/farmacologia , Testes de Sensibilidade Microbiana , Nistatina/farmacologia , Prata/farmacologia
17.
Molecules ; 25(24)2020 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-33322412

RESUMO

The introduction of antifungals in clinical practice has an enormous impact on the provision of medical care, increasing the expectancy and quality of life mainly of immunocompromised patients. However, the emergence of pathogenic fungi that are resistant and multi-resistant to the existing antifungal therapy has culminated in fungal infections that are almost impossible to treat. Therefore, there is an urgent need to discover new strategies. The marine environment has proven to be a promising rich resource for the discovery and development of new antifungal compounds. Thus, this review summarizes more than one hundred marine natural products, or their derivatives, which are categorized according to their sources-sponges, bacteria, fungi, and sea cucumbers-as potential candidates as antifungal agents. In addition, this review focus on recent developments using marine antifungal compounds as new and effective approaches for the treatment of infections caused by resistant and multi-resistant pathogenic fungi and/or biofilm formation; other perspectives on antifungal marine products highlight new mechanisms of action, the combination of antifungal and non-antifungal agents, and the use of nanoparticles and anti-virulence therapy.


Assuntos
Antifúngicos/química , Produtos Biológicos/química , Micoses/tratamento farmacológico , Animais , Bactérias , Bioensaio , Química Farmacêutica , Farmacorresistência Fúngica/efeitos dos fármacos , Fungos , Humanos , Nanopartículas/química , Poríferos , Espécies Reativas de Oxigênio , Pepinos-do-Mar , Virulência
18.
Molecules ; 25(10)2020 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-32455828

RESUMO

A series of thirteen xanthones 3-15 was prepared based on substitutional (appendage) diversity reactions. The series was structurally characterized based on their spectral data and HRMS, and the structures of xanthone derivatives 1, 7, and 8 were determined by single-crystal X-ray diffraction. This series, along with an in-house series of aminated xanthones 16-33, was tested for in-vitro antimicrobial activity against seven bacterial (including two multidrug-resistant) strains and five fungal strains. 1-(Dibromomethyl)-3,4-dimethoxy-9H-xanthen-9-one (7) and 1-(dibromomethyl)-3,4,6-trimethoxy-9H-xanthen-9-one (8) exhibited antibacterial activity against all tested strains. In addition, 3,4-dihydroxy-1-methyl-9H-xanthen-9-one (3) revealed a potent inhibitory effect on the growth of dermatophyte clinical strains (T. rubrum FF5, M. canis FF1 and E. floccosum FF9), with a MIC of 16 µg/mL for all the tested strains. Compounds 3 and 26 showed a potent inhibitory effect on two C. albicans virulence factors: germ tube and biofilm formation.


Assuntos
Antibacterianos/química , Biofilmes/efeitos dos fármacos , Bibliotecas de Moléculas Pequenas/química , Xantonas/química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/patogenicidade , Biofilmes/crescimento & desenvolvimento , Candida albicans/efeitos dos fármacos , Candida albicans/patogenicidade , Cristalografia por Raios X , Humanos , Testes de Sensibilidade Microbiana , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/farmacologia , Difração de Raios X , Xantonas/síntese química , Xantonas/farmacologia
19.
Rev Port Cir Cardiotorac Vasc ; 27(2): 117-119, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32707619

RESUMO

Tetralogy of Fallot is very prevalent with correction techniques well standardized. Whenever infundibular incisions are needed, patch reconstruction seems mandatory. Recently, the small intestinal submucosal (CorMatrix, MAC's Medical Group,) patch was introduced, with optimal results in pre-clinical studies. However, clinical results do not match its pre-clinical promises, particularly when used in right ventricular outflow tract and pulmonary artery reconstructions. We describe a case of Tetralogy of Fallot for which small intestinal submucosal (CorMatrix) patch was used as a trans-annular patch, with development of a massive pseudo-aneurysm.


Assuntos
Falso Aneurisma , Tetralogia de Fallot , Ventrículos do Coração , Humanos , Artéria Pulmonar
20.
Mycopathologia ; 184(5): 645-651, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31506883

RESUMO

Infections caused by filamentous fungi are rising in incidence and became a serious health concern. Their rapid and reliable identification in the clinical laboratory is essential for an early and accurate diagnosis to guide timely therapy. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been reported as a rapid and reliable method for identification of bacteria and yeasts isolated from clinical samples. However, it has less used for molds identification. The aim of this study was to evaluate Vitek® MS (a MALDI-TOF MS system) ability to identify molds and differentiate species within a complex. A collection of 90 filamentous fungi, 70 clinical and 20 environmental isolates, was studied by morphological and molecular methods and by Vitek® MS. Seventy-four isolates (82.2%) were identified using Vitek® MS v3.0 at Genus/Complex/Species group level; within these, 47/74 (63.5%) were correctly identified at species level and only one was misidentified. In contrast, 16/90 isolates (17.8%) were not identified, of which 13 were not present in the database. Results here expressed favor Vitek® MS v3.0 as a very useful system for identification of most common clinical isolates of filamentous fungi. Accordingly, it may be an important tool for clinical microbiology laboratories in their task to answer to clinicians, adequately and rapidly, helping in proper patient's management.


Assuntos
Testes Diagnósticos de Rotina/métodos , Fungos/classificação , Fungos/isolamento & purificação , Técnicas Microbiológicas/métodos , Micoses/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Humanos , Sensibilidade e Especificidade
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