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Novel open-chain merocytochalasans, perochalasins A-C (1-3), containing an unusual N-O six-membered heterocyclic moiety, were isolated from cultures of the marine-derived Peroneutypa sp. M16 fungus, along with cytochalasin Z27 (4), cytochalasin Z28 (5), [12]-cytochalasin (6), and phenochalasin B (7). The structures of compounds 1-3 were established by analysis of the spectroscopic data. Full genome sequencing of Peroneutypa sp. M16 enabled the identification of a cytochalasan biosynthetic gene cluster and a proposal for the biosynthetic assembly of perochalasins. The proposal is supported by the nonenzymatic conversion of phenochalasin B (7) into 1-3, based on isotope-labeled hydroxylamine (15NH2OH and ND2OD) feeding studies in vivo and in vitro. In contrast to other merocytochalasans, these are the first cytochalasans confirmed to arise via nucleophilic addition and at a distinct location from the reactive macrocycle olefin, potentially expanding further the range of merocytochalasans to be discovered or engineered. Cytochalasin Z27 (4) exhibited antiplasmodial activities in the low micromolar range against the chloroquine-sensitive Plasmodium falciparum 3D7 strain as well as against resistant strains of the parasite (Dd2, TM90C6B, and 3D7r_MMV848).
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Several under-explored Aspergillus sp. produce intriguing heptapeptides containing a γ-aminobutyric acid (GABA) residue with as yet unknown biological functions. In this study, a new GABA-containing heptapeptide - unguisin J (1) - along with known unguisin B (2) were isolated from a solid culture of Aspergillus heteromorphus CBS 117.55. The structure of compound 1 was elucidated by extensive 1D and 2D NMR spectroscopic analysis including HSQC, HMBC, COSY, and 2D NOESY as well as HRESIMS. The stereochemistry of 1 and 2 was determined by Marfey's method. A biosynthetic gene cluster (BGC) encoding unguisins B and J was compared to characterized BGCs in other Aspergillus sp. Since the unguisin family of heptapetides incorporate different amino acid residues at different positions of the peptide, the A and C domains of the UngA NRPS were analyzed in an attempt to understand the lack of substrate specificity observed.
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The present work reports the effects of chemical elicitors and epigenetic modifiers on the production and diversification of secondary metabolites produced by Anthostomella brabeji - an endophytic fungus isolated from Paepalanthus planifolius (Eriocaulaceae). The fungus was cultivated under four different small-scale culture conditions in potato dextrose broth (PDB): PDB (control), PDB + Mg+2, PDB + Cu+2 and PDB + 5-AZA (5-azacytidine). The incorporation of Cu+2 into PDB medium yielded the most promising results as the most significant differences in the metabolic profile of A. brabeji were observed under this condition. The chemical analysis of the PDB + Cu+2 extract resulted in the isolation of seven metabolites, including three new benzofuran derivatives (2, 4 and 6) and four known compounds (1, 3, 5 and 7). The metabolites were tested using the Gram-positive bacterium Staphylococcus aureus, Gram-negative bacteria Salmonella sp. and Escherichia coli, and six yeasts of Candida albicans and non-albicans. The EtOAc extract (PDB + Cu+2), and compounds 1, 2 and 7 exhibited relevant antifungal activity against Candida spp., with minimum inhibitory concentration ranging from 62.5 to 500.0 µg/mL.
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Ascomicetos , Eriocaulaceae , Cobre , Estrutura Molecular , Extratos Vegetais/químicaRESUMO
Metabolomics analyses and improvement of growth conditions were applied toward diversification of phomactin terpenoids by the fungus Biatriospora sp. CBMAI 1333. Visualization of molecular networking results on Gephi assisted the observation of phomactin diversification and guided the isolation of new phomactin variants by applying a modified version of chemometrics based on a fractional factorial design. Consequentially, the first nitrogen-bearing phomactin, phomactinine (1), with a new rearranged carbon skeleton, was isolated and identified. The strategy combining metabolomics and chemometrics can be extended to include bioassay potency, structure novelty, and metabolic diversification connected or not to genomic analyses.
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Ascomicetos , Ascomicetos/química , Estrutura MolecularRESUMO
Bioassay-guided investigation of the EtOAc-soluble extract of a culture of the marine-derived fungus Peroneutypa sp. M16 led to the isolation of seven new polyketide- and terpenoid-derived metabolites (1, 2, 4-8), along with known polyketides (3, 9-13). Structures of compounds 1, 2, and 4-8 were established by analysis of spectroscopic data. Absolute configurations of compounds 1, 2, 4, 6, 7, and 8 were determined by the comparison of experimental ECD spectra with calculated CD data. Compound 5 exhibited moderate antiplasmodial activity against both chloroquine-sensitive and -resistant strains of Plasmodium falciparum.
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Policetídeos , Xylariales , Policetídeos/química , Terpenos/química , Estrutura Molecular , Extratos VegetaisRESUMO
Comparative metabolomics analysis of nonphytotoxic endophytic Colletotrichum spp. isolated from Anthurium alcatrazense endemic to Alcatrazes island (Brazil) and phytopathogenic Colletotrichum spp. isolated from the mainland of Brazil revealed significant differences in chemical composition. Examination of endophytic Colletotrichum spp. from Alcatrazes island led to the discovery of a 26-member macrolactone, colletotrichumolide (1), containing a phosphatidyl choline side chain. Further examination of the phytopathogenic strains from the mainland identified a family of phytopathogenic metabolites not present in the nonpathogenic island-derived strains, suggesting that geographical isolation could influence the secondary metabolism of fungal strains.
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Colletotrichum , Colletotrichum/química , Brasil , Metabolismo SecundárioRESUMO
The oil spill of unknown origin that hit the Brazilian coast in 2019 led to the first activation of the National Contingency Plan, outside the scope of an exercise. The Brazilian Navy, the Environmental Agency and the Oil Agency worked together during the oil spill emergency at the Federal level, as the plan´s Monitoring and Evaluation Group. However, the distinctive characteristics and proportions of the incident demanded unanticipated actions. Therefore, this work aims to analyze the response actions, to evaluate policies and procedures in place and to propose improvements for the future. The paper discusses the anonymous and voluntary feedback from 150 professionals, obtained during the event, through a structured online form. The results of the survey are compared to findings in official documents, especially the Incident´s Final Report, prepared by the Brazilian Navy. The conclusion is that the Incident Command System, used to manage and coordinate clean-up operations, provided a swift and coordinated response as the oil reached the shore of 11 states. In contrast, there is a need to review the legal framework, including the Decree that established the National Contingency Plan, revisit response manuals, improve liaison and enhance communication channels among different authorities in the Brazilian Government.
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Poluição por Petróleo , BrasilRESUMO
Toads belonging to the Bufonidae family have a pair of paratoid glands that store highly toxic a biological secretion with varied chemical composition, that act as a chemical defense against microbial infections and predators. The paratoid gland secretion (PGS) of bufonids is rich in bioactive steroids, alkaloids, proteins, bufadienolides and bufotoxins. In the present investigation we performed a systematic analysis of the chemical profile of PGS obtained from the Bufonidae toad Rhinella jimi ("Cururu" toad) collected at three different regions of Piauí state, Northeastern Brazil. Our aim was to investigate the PGS variation related to the season of animals collection, geographic distribution and gender of the animals. The methanolic extracts of PGS were analyzed by UPLC-QToF-MS/MS. Principal component analysis (PCA) were applied to the data set obtained by the UPLC-QToF-MS/MS analyses. Among 23 compounds identified, dehydrobufotenine, suberoyl arginine, 3-(N-suberoyl-argininyl) telocinobufagin, 3-(N-suberoyl-argininyl) marinobufagin, telocinobufagin, marinobufagin and 3-(N-suberoyl-argininyl) bufalin were detected in all PGS. Minimal variations in the composition of paratoid secretions of R. jimi were observed related to distinct geographical and seasonal parameters. R. jimi female animals presented the most diverse chemical composition in its PGS. With this comparative study, unprecedented for the species, it was possible to observe that the secretions of the paratoid glands produced by R. jimi from different regions of the state of Piauí, at different times of the year, presented consistent chemical composition, with discrete particularities in the number and nature chemistry of its constituents.
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Bufonidae , Metanol , Espectrometria de Massas em Tandem , Animais , Brasil/epidemiologia , Bufonidae/metabolismo , Feminino , Metanol/metabolismoRESUMO
As part of our continuing efforts to discover new bioactive compounds from endophytic fungal sources, we have investigated the extract of the Paraphaeosphaeria sporulosa F03 strain. The study led to the isolation of four new 3-methyl-isoquinoline alkaloids (1: â-â4: ) and four known polyketides (5: â-â8: ). The structures of compounds 1: â-â4: were elucidated by 1D and 2D NMR experiments and HRMS analysis. The absolute configuration of 4: was determined by comparison of its experimental electronic circular dichroism spectrum with calculated data. Compounds 1: â-â4: exhibited antifungal activity with minimal inhibitory concentration values ranging from 6.25â-â50 µg/mL against six Candida species but they did not present any cytotoxic activity against the human tumor cell lines A549 (lung), MCF-7 (breast), and HepG2 (hepatocellular). In addition, compound 4: exhibited antiplasmodial activity in the low micromolar range (IC50 = 4 µM).
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Alcaloides , Antimaláricos , Eriocaulaceae , Policetídeos , Antifúngicos/farmacologia , Antimaláricos/farmacologia , Ascomicetos , Endófitos/química , Humanos , Isoquinolinas/química , Isoquinolinas/farmacologia , Estrutura Molecular , Extratos Vegetais , Policetídeos/química , Policetídeos/farmacologiaRESUMO
This work reports on the preparation of a drying process from the ethanolic extract of Muirapuama and its characterization through green analytical techniques. The spray-drying processes were performed by using ethanolic extract in a ratio of 1:1 extract/excipient and 32 factorial design. The properties of dried powder were investigated in terms of total flavonoid content, moisture content, powder yield, and particle size distribution. An analytical eco-scale was applied to assess the greenness of the developed protocol. Ultra-high performance liquid chromatography (UHPLC)with reduced solvent consumption in the analysis was compared to the conventional HPLC method. A Fourier transform near-infrared (FT-NIR) spectroscopic method was applied based on the principal component scores for the prediction of extract/excipient mixtures and partial least squares regression model for quantitative analysis. NIR spectroscopy is an economic, powerful, and fast methodology for the detection of excipient in muirapuama dried extracts, generating no residue in the analysis. Scanning electron microscopy (SEM) images showed samples with a higher concentration of excipient, presenting better morphological characteristics and a lower moisture absorption rate. An eco-scale score value of 85 was achieved for UHPLC and 100 was achieved for NIR (excellent green analysis). Above all, these methods are rapid and green for the routine analysis of herbal medicines based on dried extracts.
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Química Verde , Oleaceae/química , Extratos Vegetais/análise , Dessecação , Extratos Vegetais/químicaRESUMO
Incorporation of the epigenetic modifier suberoylanilide hydroxamic acid (SAHA) into a potato dextrose broth culture of the endophytic fungus Aspergillus sp. AST0006 affected its polyketide biosynthetic pathway providing two new 3-(4-oxopyrano)-chromen-2-ones, aspyranochromenones A (1) and B (2), and the isocoumarin, (-)-6,7-dihydroxymellein (3). Eight additional metabolites (4-11) and two biotransformation products of SAHA (12-13) were also encountered. The planar structures and relative configurations of the new metabolites 1-2 were elucidated with the help of high-resolution mass, 1D and 2D NMR spectroscopic data and the absolute configurations of 1-3 were determined by comparison of experimental and calculated ECD data. Possible biosynthetic pathways to 1 and 2 are presented.
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OBJECTIVES: To determine the physicochemical and microbiological stability of sulfadiazine suspensions (100 mg/mL) in simple syrup (A) and sorbitol (B) formulations prepared from commercially available tablets. METHODS: An ultra-performance liquid chromatographic assay was developed and validated to determine the chemical stability of sulfadiazine. Three samples were prepared and stored at 5 and 25 °C and assayed at 0, 7, 14 and 30 days. Physical parameters (appearance, pH, particle size and viscosity) were also monitored. Microbiological examination was performed through the suitable counting method. RESULTS: The formulations presented a sulfadiazine concentration of around 95% at the beginning at both temperatures. There was some variation in pH, viscosity and particle size distribution over time. The samples met the pharmacopoeia criteria of microbiological quality over 30 days, but only sulfadiazine formulated in syrup stored at 25 °C was suitable for use after one week. CONCLUSION: The sulfadiazine suspension in simple syrup was chosen as the most suitable formulation because it demonstrated stability for 14 days at room temperature, providing an alternative liquid dosage form of sulfadiazine for congenital toxoplasmosis treatment.
OBJECTIFS: Déterminer la stabilité physicochimique et microbiologique de suspensions de sulfadiazine (100 mg/mL) dans des formulations de sirop simple (A) et de sorbitol (B) préparées à partir de comprimés disponibles dans le commerce. MÉTHODES: Un test de chromatographie liquide ultra-performante a été développé et validé pour déterminer la stabilité chimique de la sulfadiazine. Trois échantillons ont été préparés et stockés à 5 ºC et à 25 ºC et analysés à 0, 7, 14 et 30 jours. Les paramètres physiques (apparence, pH, granulométrie et viscosité) ont également été contrôlés. Un examen microbiologique a été effectué par la méthode de comptage appropriée. RÉSULTATS: Les formulations présentaient une concentration en sulfadiazine d'environ 95% au début aux deux températures. Il y avait une certaine variation du pH, de la viscosité et de la distribution de la taille des particules au fil du temps. Les échantillons répondaient aux critères de pharmacopée pour la qualité microbiologique aprè 30 jours, mais seule la sulfadiazine formulée dans du sirop conservé à 25 ºC pouvait être utilisée après une semaine. CONCLUSION: La suspension de sulfadiazine dans un sirop simple a été choisie comme la formulation la plus appropriée car elle a démontré une stabilité à 14 jours à température ambiante, fournissant une forme galénique liquide alternative de sulfadiazine pour le traitement de la toxoplasmose congénitale.
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Antibacterianos/uso terapêutico , Sulfadiazina/uso terapêutico , Toxoplasmose Congênita/tratamento farmacológico , Administração Oral , Antibacterianos/administração & dosagem , Antibacterianos/química , Armazenamento de Medicamentos , Humanos , Recém-Nascido , Sulfadiazina/administração & dosagem , Sulfadiazina/química , Suspensões , ComprimidosRESUMO
Curvularia lunata, isolated from the capitula of Paepalanthus chiquitensis (Eriocaulaceae), was cultured in potato dextrose broth (PDB) medium. The ethyl acetate extract yielded two new spirocyclic γ-lactams (3 and 4), and five known compounds, namely: triticones E (1) and F (2), 5-O-methylcurvulinic acid (5), curvulinic acid (6) and curvulin (7). Their structures were elucidated by spectroscopic analysis and by the comparison with literature data. Besides, a computational study was used to elucidate the absolute configuration of the C - 3' in the compounds (3) and (4). The extract and the compounds (1 and 2), (6) and (7) were assayed against gram-positive and gram-negative bacteria and fluconazole-resistant yeast. The triticones (1) and (2) showed good antibacterial activity for Escherichia coli, with a minimum inhibitory concentration of 62.5 µg/mL.
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Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ascomicetos/química , Lactamas/química , Antibacterianos/química , Antifúngicos/química , Bactérias/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura MolecularRESUMO
Three new benzaldehyde derivatives, sporulosaldeins Aâ-âC (1: -3: ), and 3 new benzopyran derivatives, sporulosaldeins Dâ-âF (4: -6: ), were discovered from an endophytic fungus, Paraphaeosphaeria sp. F03, which was isolated from Paepalanthus planifolius leaves. Compounds 1: -6: were elucidated by 1- and 2-dimensional nuclear magnetic resonance experiments and high-resolution mass spectrometry analysis. The absolute configuration of compound 5: was determined through the comparison of experimental and calculated electronic circular dichroism data. Compounds 1: -6: were found to exhibit antifungal activity with minimum inhibitory concentration (MIC) values of 7.8â-â250 µg/mL and racemic mixture of compound 6: exhibited weak cytotoxicity against MCF-7 and LM3 with IC50 values of 34.4 and 39.2 µM, respectively.
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Antibacterianos/farmacologia , Antifúngicos/farmacologia , Ascomicetos/química , Benzaldeídos/farmacologia , Benzopiranos/farmacologia , Citotoxinas/farmacologia , Animais , Antibacterianos/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Benzaldeídos/química , Benzaldeídos/isolamento & purificação , Benzopiranos/química , Benzopiranos/isolamento & purificação , Linhagem Celular Tumoral , Citotoxinas/química , Citotoxinas/isolamento & purificação , Endófitos , Humanos , Espectroscopia de Ressonância Magnética , Espectrometria de Massas , Camundongos , Testes de Sensibilidade Microbiana , Estrutura MolecularRESUMO
A cost-effective approach to gather information in a smart city is to embed sensors in vehicles such as buses. To understand the limitations and opportunities of this model, it is fundamental to investigate the spatial coverage of such a network, especially in the case where only a subset of the buses have a sensing device embedded. In this paper, we propose a model to select the right subset of buses that maximizes the coverage of the city. We evaluate the model in a real scenario based on a large-scale dataset of more than 5700 buses in the city of Rio de Janeiro, Brazil. Among other findings, we observe that the fleet of buses covers approximately 5655 km of streets (approximately 47% of the streets) and show that it is possible to cover 94% of the same streets if only 18% of buses have sensing capabilities embedded.
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Objective: To evaluate the sensitivity of electromyography and ultrasonography in diagnosing carpal tunnel syndrome (CTS), in comparison with physical examination, which is considered to be the gold standard. Methods: In this cross-sectional study, the medical files of 56 patients with 70 hands affected by CTS who were attended between March 2010 and June 2012 were reviewed. The study included patients with a clinical diagnosis of CTS. The sensitivity of the complementary examinations was analyzed and compared with physical examination. Results: Nocturnal symptoms were found in 96.4%, thenar atrophy in 62.5% and abnormal sense of touch in 50%. The sensitivities found were: ultrasonography, 67.1% (95% CI: 55.7%78.6%); an association of physical examination tests, 95.7% (95% CI: 90.0%100%); and electromyography, 98.6% (95% CI: 95.7%100%). The presence of atrophy, abnormalities of the sense of touch and longer-duration symptoms increased the sensitivity of ultrasonography and physical examination. Conclusion: The sensitivity of ultrasonography for CTS was lower than that of electromyography and physical examination...
Objetivo: Avaliar a sensibilidade da eletroneuromiografia (ENMG) e da ultrassonografia (USN) no diagnóstico de síndrome do túnel do carpo (STC) comparada com a do exame físico, considerado padrão-ouro. Métodos: Estudo seccional pela análise de prontuários de 56 pacientes com 70 mãos acometidas com STC entre março de 2010 e junho de 2012. A sensibilidade dos exames complementares foi analisada e comparada com a do exame físico. Resultados: Constataram-se sintomas noturnos em 96,4%, hipotrofia tenar em 62,5% e alteracão do tato em 50%. A sensibilidade da USG foi de 67,1% (95% IC, 55,7%-78,6%); a da associacão dos testes do exame físico, de 95,7 (95% IC, 90,0%-100%); e a da ENMG, de 98,6% (95% IC, 95,7%-100%). A presenca de hipotrofia, de alteracões no tato e o maior tempo dos sintomas aumentaram a sensibilidade da USG e do exame físico. Conclusão: A sensibilidade da USG para a STC foi inferior à da ENMG e à do exame físico...
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Humanos , Masculino , Feminino , Eletromiografia , Síndrome do Túnel CarpalRESUMO
OBJECTIVE: To evaluate the sensitivity of electromyography and ultrasonography in diagnosing carpal tunnel syndrome (CTS), in comparison with physical examination, which is considered to be the gold standard. METHODS: In this cross-sectional study, the medical files of 56 patients with 70 hands affected by CTS who were attended between March 2010 and June 2012 were reviewed. The study included patients with a clinical diagnosis of CTS. The sensitivity of the complementary examinations was analyzed and compared with physical examination. RESULTS: Nocturnal symptoms were found in 96.4%, thenar atrophy in 62.5% and abnormal sense of touch in 50%. The sensitivities found were: ultrasonography, 67.1% (95% CI: 55.7%-78.6%); an association of physical examination tests, 95.7% (95% CI: 90.0%-100%); and electromyography, 98.6% (95% CI: 95.7%-100%). The presence of atrophy, abnormalities of the sense of touch and longer-duration symptoms increased the sensitivity of ultrasonography and physical examination. CONCLUSION: The sensitivity of ultrasonography for CTS was lower than that of electromyography and physical examination.
OBJETIVO: Avaliar a sensibilidade da eletroneuromiografia (ENMG) e da ultrassonografia (USN) no diagnóstico de síndrome do túnel do carpo (STC) comparada com a do exame físico, considerado padrão-ouro. MÉTODOS: Estudo seccional pela análise de prontuários de 56 pacientes com 70 mãos acometidas com STC entre março de 2010 e junho de 2012. A sensibilidade dos exames complementares foi analisada e comparada com a do exame físico. RESULTADOS: Constataram-se sintomas noturnos em 96,4%, hipotrofia tenar em 62,5% e alteração do tato em 50%. A sensibilidade da USG foi de 67,1% (95% IC, 55,7%-78,6%); a da associação dos testes do exame físico, de 95,7 (95% IC, 90,0%-100%); e a da ENMG, de 98,6% (95% IC, 95,7%-100%). A presença de hipotrofia, de alterações no tato e o maior tempo dos sintomas aumentaram a sensibilidade da USG e do exame físico. CONCLUSÃO: A sensibilidade da USG para a STC foi inferior à da ENMG e à do exame físico.
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O osteoma osteoide é um tumor benigno do osso que se apresenta geralmente com dor noturna em adultos jovens, aliviada por repouso e salicilatos. Pode acometer qualquer osso, mas sua ocorrência no ilíaco é infrequente. Os autores descrevem dois casos de osteoma osteoide intramedular, localizado junto à articulação sacroilíaca, com sintomas que simulavam dor ciática e cujo diagnóstico se deu de forma tardia, apesar de o exame radiológico inicial mostrar lesão esclerótica em ambos os casos. O diagnóstico foi ratificado por tomografia computadorizada e o tratamento proposto foi a ressecção em bloco da lesão, com excisão do nidus. O diagnóstico definitivo foi confirmado pelo exame histopatológico. No seguimento de longo prazo, ambos estão assintomáticos e observou-se completa remodelação óssea no sítio cirúrgico. Os autores enfatizam as características típicas do tumor, a localização não usual, o diagnóstico diferencial e o tratamento.
Osteoid osteoma is a benign bone tumor that generally presents with nighttime pain among young adults and is relieved by rest and salicylates. It can affect any bone, but occurrences in the iliac are unusual. The authors describe two cases of intramedullary osteoid osteoma next to the sacroiliac joint, with symptoms that simulated sciatic pain. The cases were diagnosed late, although the initial radiographs showed sclerotic lesions in both cases. The diagnosis was confirmed by means of CT scan and the nidus was excised surgically through en bloc resection. The definitive diagnosis was given by means of histopathological examination. Over long-term follow-up, both cases remained asymptomatic and complete bone remodeling at the surgical site was observed. The authors highlight the typical characteristics of the tumor, the unusual location, the differential diagnosis and the treatment.