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1.
Cogn Process ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632149

RESUMO

Prospective memory (PM) refers to the ability to remember to execute an intention in the future without having a permanent reminder. These intentions can be performed when they are not relevant or become no-longer needed, the so-called "commission errors". The present study aims to understand the effect of cue salience on PM commission errors with unperformed intentions and on the ongoing task performance-associated costs. Through a between-subjects design, eighty-one participants were assigned to 3 conditions: the no-PM condition, which served as control, and the salient and nonsalient conditions, which were asked to perform a lexical decision task and an incomplete nonfocal prospective memory task (i.e. no PM cues were presented). Subsequently, participants were instructed to no longer execute the prospective intention. In the second phase, a lexical decision task occurred again, including irrelevant PM cues, which should not be answered as such. In the salient condition, cues were salient (i.e. presented in red or blue background). In contrast, in the nonsalient condition, PM cues appeared on a black background, as any other stimuli. In the no-PM control condition, participants only performed an LDT. A commission error occurred when the (irrelevant) intention was performed in this second phase. Results showed that more participants performed a commission error in the presence of salient cues, even when PM intentions became irrelevant. Additionally, when cues were not salient, participants took longer to answer the LDT, as reasoned by the spontaneous retrieval theory. These findings are discussed according to the dual-mechanism account.

2.
Int J Mol Sci ; 23(21)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36362321

RESUMO

Overexpression of melanin contributes to darkening of plant and fruit tissues and skin hyperpigmentation, leading to melasma or age spots. Although melanin biosynthesis is complex and involves several steps, a single enzyme known as tyrosinase is key to regulating this process. The melanogenesis pathway is initiated by oxidation of the starting material l-tyrosine (or l-DOPA) to dopaquinone by tyrosinase; the resulting quinone then serves as a substrate for subsequent steps that eventually lead to production of melanin. Medicinal plants are considered a good source of tyrosinase inhibitors. This study investigated the tyrosinase inhibitory activity of A. mollis leaf extracts and their phytochemicals. Significant activity was verified in the ethanol extract -EEt (IC50 = 1.21 µg/mL). Additionally, a kinetic study showed that this tyrosinase inhibition occurs by DIBOA (2,4-dihydroxy-1,4-benzoxazin-3-one) and verbascoside contribution through a non-competitive reaction mechanism. A synergistic effect on tyrosinase inhibition was observed in the binary combination of the compounds. In conclusion, both EEt and a mixture of two of its phytochemicals can be effective tyrosinase inhibitors and can be used as a bleaching agent for cosmetic formulations in the future.


Assuntos
Acanthaceae , Monofenol Mono-Oxigenase , Monofenol Mono-Oxigenase/metabolismo , Melaninas/metabolismo , Extratos Vegetais/farmacologia , Compostos Fitoquímicos , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química
3.
Int J Mol Sci ; 23(15)2022 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-35955963

RESUMO

Alzheimer's disease (AD) is the most common neurodegenerative disorder affecting elderly people worldwide. Currently, there are no effective treatments for AD able to prevent disease progression, highlighting the urgency of finding new therapeutic strategies to stop or delay this pathology. Several plants exhibit potential as source of safe and multi-target new therapeutic molecules for AD treatment. Meanwhile, Eucalyptus globulus extracts revealed important pharmacological activities, namely antioxidant and anti-inflammatory properties, which can contribute to the reported neuroprotective effects. This review summarizes the chemical composition of essential oil (EO) and phenolic extracts obtained from Eucalyptus globulus leaves, disclosing major compounds and their effects on AD-relevant pathological features, including deposition of amyloid-ß (Aß) in senile plaques and hyperphosphorylated tau in neurofibrillary tangles (NFTs), abnormalities in GABAergic, cholinergic and glutamatergic neurotransmission, inflammation, and oxidative stress. In general, 1,8-cineole is the major compound identified in EO, and ellagic acid, quercetin, and rutin were described as main compounds in phenolic extracts from Eucalyptus globulus leaves. EO and phenolic extracts, and especially their major compounds, were found to prevent several pathological cellular processes and to improve cognitive function in AD animal models. Therefore, Eucalyptus globulus leaves are a relevant source of biological active and safe molecules that could be used as raw material for nutraceuticals and plant-based medicinal products useful for AD prevention and treatment.


Assuntos
Doença de Alzheimer , Óleos Voláteis , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/patologia , Animais , Biomassa , Florestas , Humanos , Óleos Voláteis/farmacologia , Óleos Voláteis/uso terapêutico , Fenóis/farmacologia
4.
Cogn Process ; 22(3): 411-434, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33694121

RESUMO

The definition of episodic memory has evolved into a multifaceted concept that gathered great attention in several research areas in psychology and neuroscience. Prospective memory (PM), or the ability to remember to perform delayed intentions at a later moment in the future, represents one side of this capacity for which that has been a growing interest. In this review, we examined a counterintuitive finding: PM intentions may persist and affect our behaviour despite successful goal attainment and task completion, which in daily life may be as serious as taking medication twice. This review aims to elucidate the existing knowledge and identify some unresolved questions concerning this specific memory failure. Therefore, this review provides an overview of the uprising research dedicated to both PM omission and commission errors, including an analysis of its definitions, of the current theoretical approaches of PM retrieval, and the main procedures used in this field to offer an integrative perspective on this topic. Finally, the last section is devoted to discussing future directions to test the predictions of our suggested theoretical explanations for PM deactivation. This might be an avenue for research that is likely to extend our understanding of episodic memory's usefulness in everyday life.


Assuntos
Memória Episódica , Atenção , Humanos , Intenção , Rememoração Mental , Testes Neuropsicológicos , Estudos Retrospectivos
5.
Memory ; 28(3): 374-385, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32043427

RESUMO

Recent studies consistently show that prospective memory (PM) intentions are not always deactivated when no-longer needed and might be erroneously performed upon encountering the once relevant cue - termed PM commission errors. However, empirical evidence on the potential mechanisms that might lead to this kind of memory failure remains mostly unexplored. This study aimed to investigate the influence of the ongoing task demands on PM deactivation of non-performed intentions. Younger adults, except for those in the no-PM condition, were asked to perform a PM task and were then told that the intention was finished. Later, they perform a lexical decision task with some trials containing (irrelevant) PM cues while simultaneously carrying out a counting recall task with two levels of difficulty. The results showed a higher risk of PM commission errors under moderate cognitive load (74%) as compared to the no-load condition (40%). Results also show that commission error risk did not increase in the high-load (54%) compared with the moderate-load condition. Furthermore, comparisons of the ongoign task performance between the no-PM condition and the other conditions with a PM task requirement support that commission errors might arise from a spontaneous PM retrieval. The implications of these findings are discussed within the dual-mechanisms account.


Assuntos
Cognição/fisiologia , Sinais (Psicologia) , Memória Episódica , Rememoração Mental/fisiologia , Adulto , Feminino , Humanos , Intenção , Masculino , Análise e Desempenho de Tarefas , Adulto Jovem
6.
Parasitol Res ; 117(4): 1087-1093, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29435717

RESUMO

Hoferellus azevedoi n. sp. was found in the urinary bladder of Chaetobranchus flavescens Heckel, 1840 from the Arari River on Marajó Island in Pará, Brazil. This is the first record of a species of the genus Hoferellus in a host from the Brazilian Amazon region. The new species has disporous and polysporous plasmodia, which vary in size and shape, with some being found adhered to the epithelium of the urinary bladder, and others floating in the liquid. The mature spores are sub-spherical in the sutural view, with a number of peripheral projections around the whole surface of the spore. In the sutural view, the spores are 5.3 ± 0.2 (5.2-5.6) µm in length and 7.0 ± 0.7 (6.3-7.7) µm in width, with two piriform polar capsules of equal size, 2.5 ± 0.2 (2.3-2.8) µm long and 1.8 ± 0.2 (1.6-2.0) µm wide. Based on a partial (1312 bps) sequence of the SSU rDNA gene, Hoferellus azevedoi n. sp. was distinguished from all the other myxozoan species deposited in GenBank. Phylogenetically, based on Bayesian inference and p-distances, the new species was allocated to the "Freshwater Urinary-Bladder" clade, together with other myxozoan parasites of the excretory system. Based on the morphological data, supported by the partial sequence of the SSU rDNA gene, we describe a new species of myxozoan, Hoferellus azevedoi n. sp.


Assuntos
Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Bexiga Urinária/parasitologia , Animais , Teorema de Bayes , Brasil , DNA Ribossômico/genética , Myxozoa/genética , Myxozoa/isolamento & purificação , Filogenia , Esporos/fisiologia
7.
Parasitol Res ; 117(11): 3537-3545, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30238187

RESUMO

Ellipsomyxa arariensis n. sp. was found in the gallbladder of Pygocentrus nattereri Kner, 1858 and Pimelodus ornatus Kner, 1858 from the Arari River on Marajó Island in Pará, Brazil. The new species has disporous plasmodium that varies in size and shape, with ellipsoidal mature spores in the sutural view that have a curved suture line. The spores are 12.6 (12.0-13.4) µm in length and 7.3 (6.7-8.0) µm in width. The two polar capsules present in the spore are pyriform and of equal size, with subterminal openings that project in opposite directions. The polar capsules are 3.5 (3.4-4.0) µm long and 2.6 (2.5-3.2) µm wide. Based on the partial sequences of the SSU rRNA gene of the Ellipsomyxa arariensis n. sp. spores found in Pygocentrus nattereri Kner, 1858 (1325 bps) and Pimelodus ornatus Kner, 1858 (1240 bps), the new species is clearly distinct from all the other myxozoan sequences deposited in GenBank. Based on Bayesian inference and p distances, the new species belongs to the "Ellipsomyxa clade", together with all the other Ellipsomxa species, reinforcing the monophyletic status of this genus. Overall, the morphological data and the partial sequences of the SSU rRNA gene provide a conclusive diagnosis of Ellipsomyxa arariensis n. sp. as a species distinct from all the other Ellipsomyxa species described previously.


Assuntos
Peixes-Gato/parasitologia , Characidae/parasitologia , Doenças dos Peixes/parasitologia , Vesícula Biliar/parasitologia , Myxozoa/classificação , Myxozoa/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Animais , Teorema de Bayes , Brasil , Bases de Dados de Ácidos Nucleicos , Ilhas , Myxozoa/genética , Filogenia , RNA Ribossômico 18S/genética , Rios/parasitologia , Esporos de Protozoários/classificação
8.
J Eukaryot Microbiol ; 63(1): 27-36, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26095978

RESUMO

A new myxosporean species is described from the muscle of the Amazonian freshwater fish Chaetobranchopsis orbicularis (Teleostei, Cichlidae), with basis on morphometric, ultrastructural and molecular data. Numerous myxospores were observed within pseudocysts located on the hosts' dorsal and ventral muscles, near the neural spines and neural canal (spinal cord). Mature myxospores quadrangular with rounded ends in apical view, measuring 4.3 (3.6-5.0) µm in length and 5.1 (4.2-5.8) µm in width. The myxospores wall is formed by four symmetric valves. Within, four pyriform polar capsules, 2.1 (1.7-2.6) µm long and 1.3 (0.9-1.7) µm wide, located two by two in opposite sides of the myxospores longitudinal axis, each containing a polar filament forming 2-3 coils. Molecular analysis of the SSU rRNA gene by maximum likelihood, neighbor-joining and maximum parsimony confirms the parasite as a new member of the genus Kudoa, herein named Kudoa orbicularis n. sp., the second species of its genus reported from the South American freshwater fauna, and the fourth species worldwide known to occur in the freshwater environment. Furthermore, its sequence of the SSU rRNA gene constitutes the first entry of a freshwater Kudoa species in GenBank.


Assuntos
Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Músculos/parasitologia , Myxozoa/genética , Myxozoa/ultraestrutura , Doenças Parasitárias em Animais/parasitologia , Animais , Brasil , Ciclídeos/anatomia & histologia , DNA Ribossômico/genética , Myxozoa/classificação , Myxozoa/isolamento & purificação , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Esporos/ultraestrutura
9.
Parasitol Res ; 115(5): 1779-87, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26847632

RESUMO

The present study describes light microscopy, transmission electron microscopy, and molecular analyses of a myxosporid found parasitizing the gill region of the teleost fish Cichla temensis, collected from the Tocantins River, near Cametá, Pará State, Brazil. The prevalence of infection was 60 %. The spore-containing cysts that were located in the gill lamellae were oval and whitish. The spores had a mean length of 42.3 ± 0.65 µm; fusiform body, 12.8 ± 0.42-µm long and 8.6 ± 0.32-µm wide; each of the two valves exhibited a tapering tail of 29.5 ± 0.73 µm length. The spores had two polar capsules, 7.4 ± 0.16-µm long by 2.6 ± 0.08-µm wide, containing a polar filament with 5-7 twists. The spores differ from the species previously described, and phylogenetic analysis based on spore morphology and molecular aspects indicated that the fish parasite Henneguya sp. has a strong trend to form clades mainly based on the environment and host order/family. Thus, we conclude that the species belongs to the family Myxobolidae, genus Henneguya, which comprises a new species: Henneguya paraensis n. sp.


Assuntos
Ciclídeos/parasitologia , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/parasitologia , Brânquias/parasitologia , Myxozoa/classificação , Myxozoa/isolamento & purificação , Animais , Brasil/epidemiologia , Microscopia Eletrônica de Transmissão , Myxozoa/genética , Filogenia , Rios/parasitologia , Esporos/citologia
10.
Clin Endocrinol (Oxf) ; 82(3): 439-44, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24930423

RESUMO

CONTEXT: The thyroid imaging reporting and data system (TI-RADS) was designed to better select patients who had undergone fine-needle aspiration biopsies (FNABs) with high sensitivity and accuracy. However, the combination of TI-RADS scores and Bethesda system categories in indeterminate thyroid nodules has not been examined extensively. OBJECTIVE: This study aimed to stratify indeterminate thyroid nodules (Bethesda categories III, IV and V) according to risk of malignancy as determined by combining TI-RADS score with Bethesda system classification. DESIGN: Retrospective study. Histopathological, cytological and ultrasound (US) data were available for 242 cases after surgery, including 136 indeterminate nodules. METHODS: All thyroid cytopathological slides and US reports were reviewed and classified according to Bethesda system and TI-RADS categories. The malignancy rate was determined for each Bethesda category, TI-RADS score and both methods combined of indeterminate nodules. RESULTS: The malignancy rates were 8·7%, 51·3% and 67·5% for Bethesda categories III, IV and V, respectively. Based on histopathological comparison, the accuracy was 66·7% for TI-RADS greyscale. TI-RADS 3 and 4A scores were observed in 80% of Bethesda III cases, which led to 80% sensitivity and 90% of negative predictive value (NPV). In contrast, for nodules scored as TI-RADS 4B and 5, the combined cytological results of Bethesda IV and V resulted in a higher risk of malignancy (75% and 76·9%, respectively, P < 0·001). CONCLUSIONS: In view of the high NPV of TI-RADS 3/4A only in Bethesda III category, a surgical approach could be considered for lesions defined as Bethesda III, IV and V when TI-RADS 4B and 5 were concomitant.


Assuntos
Nódulo da Glândula Tireoide/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Parasitol Res ; 114(3): 1159-62, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25573695

RESUMO

A new species of Myxosporea, Henneguya aequidens sp. n. (Myxozoa: Myxobolidae), was described based on its ultrastructural features. This is a parasite of the freshwater fish Aequidens plagiozonatus, in the Peixe-boi River, Pará, Brazil. This parasite was found in the gills, in the form of whitish ellipsoid cysts with mature spores inside them. The average spore body was 15 ± 0.9 µm in length (n = 30) and 6 ± 0.8 µm in width (n = 30), and the tail measured 27 ± 0.5 µm in length (n = 15). The spores showed typical features of the genus Henneguya with two valves of equal size and two symmetrical polar capsules of 3 ± 0.3 µm in length and 2 ± 0.3 µm in width. Each polar capsule had a polar filament forming a helix from the apical region to the polar caps, with four to six turns. Based on the ultrastructural differences in morphology of these spores, the location of the parasite, and its host specificity, this parasite was described as a new species.


Assuntos
Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Animais , Brasil , Feminino , Brânquias/parasitologia , Especificidade de Hospedeiro , Masculino , Myxozoa/ultraestrutura , Rios , Esporos
12.
Acta Gastroenterol Latinoam ; 45(1): 18-23, 2015 Mar.
Artigo em Espanhol | MEDLINE | ID: mdl-26076509

RESUMO

BACKGROUND: Obesity is associated with systemic co-morbi- dities. Conservative management has a low rate ofsuccess in the short and long term. Therefore, novel endoscopic strate- gies have emerged as alternative therapies to bariatric sur- gery. The intragastric balloon (IGB) is a temporary, effective and safe endoscopic treatment for weight loss. Objectives. 1. To describe changes in body mass index (BMI) in patients who completed treatment with IGB. 2. To describe metabo- lic co-morbidities and psychological features at admission. MATERIAL AND METHODS: Patients with an age equal to or higher than 13 years-old were evaluated by a multidiscipli- nary team and categorized as "suitable" for IGB. The study took place in aprivate center in Buenos Aires, Argentina, bet- ween November 2007 andNovember 2012. The design was interventionist, longitudinal, comparative and retrospective. Interventions were: a) IGB placement was done with the usual technique; b) Nutritional monitoring was performed and a low calorie diet and an exercise plan were indicated. Follow-up was performed monthly. Main outcome measu- rements were: 1) Changes in BMI between baseline and at IGB removal according to diet and exercise compliance, 2) metabolic co-morbidities, 3) psychological traits evaluated wit checklist SCL 90. RESULTS: We included 385 patients, 66% female, mean age 41 years (range 13 to 70 years). A BMI decrease of 5 points (13 kg) was observed in the overall sample and in the 322 patients (83.6%) who completed 6 months (14 kg) (NS). The weight loss was greater in those who were compliant to diet and exercise (P = 0.0001). Most prevalent metabolic co-morbidities and psychological traits were dyslipemia and depression, respectively. CONCLUSIONS: IGB was effective in all patients. Weight loss was greater in patients compliant to diet and exercise.


Assuntos
Balão Gástrico , Obesidade Mórbida/terapia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Comorbidade , Diabetes Mellitus , Dislipidemias/complicações , Feminino , Balão Gástrico/efeitos adversos , Humanos , Hipertensão/complicações , Estudos Longitudinais , Masculino , Transtornos Mentais/complicações , Pessoa de Meia-Idade , Obesidade Mórbida/psicologia , Estudos Retrospectivos , Resultado do Tratamento , Redução de Peso , Adulto Jovem
13.
An Acad Bras Cienc ; 86(3): 1347-50, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25211110

RESUMO

A total of 40 specimens of the teleost fish Gobioides grahamae Palmer & Wheeler, 1955 were obtained from the municipality of Salvaterra on Marajó Island in the Brazilian state of Pará. Their livers were removed and processed for light microscopy. Overall, 90% of the specimens presented some degree of steatosis of the liver, which was invariably associated with the presence of Microsporidium sp. The present study confirms the occurrence of steatosis in G. grahamae associated with parasitic infections by Microsporidium. The findings indicate that the condition of otherwise healthy fishes in their natural environment may be affected negatively by parasites.


Assuntos
Fígado Gorduroso/veterinária , Doenças dos Peixes/microbiologia , Microsporidiose/veterinária , Perciformes/microbiologia , Animais , Brasil , Fígado Gorduroso/etiologia , Microsporidiose/complicações , Perciformes/classificação
14.
Endocr Res ; 39(3): 126-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24460065

RESUMO

A disparity in gender incidence has been reported in both papillary thyroid carcinoma (PTC) and chronic lymphocytic thyroiditis (CLT) diseases frequently associated and whose incidence has been increasing in parallel. We aimed to analyze differences in morphometric variables between male and female PTC patients and their relationship with the presence of concurrent CLT. The nuclear texture features of 100 hematoxylin-eosin stained nuclei from 100 consecutive classic PTC patients enrolled in our service were compared with their clinical and pathological features, including the presence of CLT. All patients were submitted to a standard management protocol and followed-up for 13-248 months (Mo = 117 months). Chromatin in women tended to present a denser and more homogeneous structure, in a less mottled pattern, with higher values of energy (p = 0.008) and diagonal moment (p = 0.032) than men. Concurrent CLT was more prevalent in women (41.42%) than in men (13.33%, p = 0.04) and was associated with higher cluster prominence values (p = 0.027), a parameter that indicates a predominance of high nuclear contrasted heterochromatin. A multivariate logistic regression analysis showed that higher cluster prominence was independently correlated with chromatin in patients who presented CLT but did not demonstrate any association between concurrent CLT and gender. We were unable to demonstrate any association between gender and any characteristic of tumor aggressiveness or patients outcome. Our results suggest that chromatin texture of hematoxylin-eosin stained nuclei in paraffin sections of PTC cells is related to both gender and concurrent CLT.


Assuntos
Carcinoma/patologia , Doença de Hashimoto/patologia , Neoplasias da Glândula Tireoide/patologia , Adulto , Carcinoma Papilar , Núcleo Celular/ultraestrutura , Cromatina/patologia , Amarelo de Eosina-(YS) , Feminino , Hematoxilina , Heterocromatina/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Coloração e Rotulagem , Câncer Papilífero da Tireoide
15.
J Inorg Biochem ; 257: 112600, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38759261

RESUMO

Rhenium complexes show great promise as anticancer drug candidates. Specifically, compounds with a Re(CO)3(NN)(py)+ core in their architecture have shown cytotoxicity equal to or greater than that of well-established anticancer drugs based on platinum or organic molecules. This study aimed to evaluate how the strength of the interaction between rhenium(I) tricarbonyl complexes fac-[Re(CO)3(NN)(py)]+, NN = 1,10-phenanthroline (phen), dipyrido[3,2-f:2',3'-h]quinoxaline (dpq) or dipyrido[3,2-a:2'3'-c]phenazine (dppz) and biomolecules (protein, lipid and DNA) impacted the corresponding cytotoxic effect in cells. Results showed that fac-[Re(CO)3(dppz)(py)]+ has higher Log Po/w and binding constant (Kb) with biomolecules (protein, lipid and DNA) compared to complexes of fac-[Re(CO)3(phen)(py)]+ and fac-[Re(CO)3(dpq)(py)]+. As consequence, fac-[Re(CO)3(dppz)(py)]+ exhibited the highest cytotoxicity (IC50 = 8.5 µM for HeLa cells) for fac-[Re(CO)3(dppz)(py)]+ among the studied compounds (IC50 > 15 µM). This highest cytotoxicity of fac-[Re(CO)3(dppz)(py)]+ are probably related to its lipophilicity, higher permeation of the lipid bilayers of cells, and a more potent interaction of the dppz ligand with biomolecules (protein and DNA). Our findings open novel avenues for rational drug design and highlight the importance of considering the chemical structures of rhenium complexes that strongly interact with biomolecules (proteins, lipids, and DNA).


Assuntos
Antineoplásicos , Complexos de Coordenação , DNA , Rênio , Rênio/química , Humanos , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Complexos de Coordenação/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/química , DNA/química , DNA/metabolismo , Fenantrolinas/química , Fenantrolinas/farmacologia , Quinoxalinas/química , Quinoxalinas/farmacologia , Fenazinas/química , Fenazinas/farmacologia , Linhagem Celular Tumoral , Células HeLa
16.
J Eukaryot Microbiol ; 60(5): 490-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23869881

RESUMO

A fish infecting myxosporean Ellipsomyxa gobioides n. sp. is described in the gallbladder of the Amazonian dragon fish Gobioides broussonnetii. Irregular disporous plasmodia (up to ~30 µm in diameter) with long branched and anastomosed pseudopodia were found attached to the gallbladder wall. Mature ellipsoid myxospores occurring floating in the bile measured 6.8 (6.5-7.0) µm (n = 30) long, 7.2 (6.9-7.5) µm (n = 15) wide, and 13.1 (12.8-13.5) (n = 25) thick. They had smooth thin valves elongated in the direction perpendicular to the plane of the straight central transverse sutural line. The two ellipsoidal polar capsules (PC) opened some distance from the sutural line on opposite sides, each measuring 4.6 (4.3-4.8) µm (n = 15) long and 2.5 (2.1-2.7) µm (n = 20) wide. Distance between PC 3.5 (3.1-3.8) µm (n = 15) in apical view. The polar filament was isofilar and consisted of a single coil with five or six turns. The objective of this study was to characterize this new species based on its morphological differences from the three previously described species. This is the first reported species of genus Ellipsomyxa from among the South American fauna.


Assuntos
Vesícula Biliar/parasitologia , Myxozoa/citologia , Myxozoa/ultraestrutura , Perciformes/parasitologia , Animais , Rios
17.
Mem Inst Oswaldo Cruz ; 108(2): 150-4, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23579792

RESUMO

A new ceratomyxid parasite was examined for taxonomic identification, upon being found infecting the gall bladder of Hemiodus microlepis (Teleostei: Hemiodontidae), a freshwater teleost collected from the Amazon River, Brazil. Light and transmission electron microscopy revealed elongated crescent-shaped spores constituted by two asymmetrical shell valves united along a straight sutural line, each possessing a lateral projection. The spores body measured 5.2 ± 0.4 µm (n = 25) in length and 35.5 ± 0.9 µm (n = 25) in total thickness. The lateral projections were asymmetric, one measuring 18.1 ± 0.5 µm (n = 25) in thickness and the other measuring 17.5 ± 0.5 µm (n = 25) in thickness. Two equal-sized subspherical polar capsules measuring 2.2 ± 0.3 µm in diameter were located at the same level, each possessing a polar filament with 5-6 coils. The sporoplasm was binucleate. Considering the morphometric data analyzed from the microscopic observations, as well as the host species and its geographical location, this paper describes a new myxosporean species, herein named Ceratomyxa microlepis sp. nov.; therefore representing the first description of a freshwater ceratomyxid from the South American region.


Assuntos
Peixes/parasitologia , Vesícula Biliar/parasitologia , Myxozoa/ultraestrutura , Animais , Brasil , Feminino , Masculino , Microscopia Eletrônica de Transmissão , Myxozoa/classificação , Myxozoa/isolamento & purificação , Rios
18.
Parasitol Res ; 112(10): 3601-5, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23907634

RESUMO

A new species of Myxosporea, Henneguya nagelii n. sp., is described parasitizing the gills of Cyphocharax nagelii collected from Peixe's River, São Paulo State, Brazil. Among the fish examined, 16.7% had gills parasitized by myxosporeans. The plasmodia were white, round, or oval and measured 150-250 µm. The mature spores were fusiform and had smooth wall. The spores measurements were the following: total length, 34.5 ± 4.2 (26.4-39.9) µm; body length, 12.0 ± 0.5 (11.2-11.9) µm; body width, 4.9 ± 0.3 (4.4-5.5) µm; and caudal process length, 22.4 ± 4.0 (14.7-27.3) µm. The polar capsules were elongated and of unequal size, with lengths of 4.9 ± 0.4 (4.0-5.9) µm and 5.2 ± 0.4 (4.6-6.0) µm for the longest and shortest axes, respectively. Capsule width was 1.8 ± 0.2 (1.5-2.2) µm. Each capsule contained a polar filament with six to eight turns. There was no mucous envelope or iodinophilous vacuole. Morphometric differences between this parasite and other species of the genus Henneguya indicated that the parasite observed in C. nagelii is a new species. This is the first species of Myxosporea described in Peixe's River.


Assuntos
Caraciformes , Doenças dos Peixes/parasitologia , Myxozoa/classificação , Rios , Animais , Brasil/epidemiologia , Doenças dos Peixes/epidemiologia , Brânquias/parasitologia , Myxozoa/anatomia & histologia
19.
Gels ; 10(1)2023 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38247759

RESUMO

Topical formulations of Acanthus mollis L. leaf and the optimization of the release of their active compounds and their topical bioavailability were investigated for the first time. In vitro, the release of active compounds from three formulations-an oil-in-water cream and two hydrogels (Carbopol 940 and Pluronic F-127)-was determined using Franz diffusion cells. Detection and quantification of the compounds was performed via high-performance liquid chromatography with a photodiode array (HPLC-PDA). DIBOA, a bioactive compound of this medicinal plant, exhibited release kinetics of the Weibull model for the Carbopol and Pluronic F-127 formulation, identifying it as a potential active agent to optimize the topical distribution of the formulations. The implications extend to applications in inflammation treatment and tyrosinase inhibition, suggesting that it can make a significant contribution to addressing skin conditions, including melanoma and various inflammatory diseases.

20.
Rev Bras Parasitol Vet ; 32(2): e005923, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37341287

RESUMO

A new species of Myxobolus parasitizing the arterial bulb and cardiac musculature of the freshwater fish Pimelodus ornatus Kner, 1858, from the Arari river in the municipality of Cachoeira do Arari, island of Marajó, Pará, Brazil, was described. In the present study, the observed prevalence of myxozoan parasites in the heart tissue of the hosts was 20% (6/30). The myxozoans observed had mature biconvex spores, slightly rounded, an anterior end with two pyriform polar capsules and a posterior end with very evident sporoplasm, measuring 8 ± 0.2 µmin length. The spore width was 5.8 ± 0.4 µm, with a thickness of 3.4 ± 0.2µm. The length of the polar capsules was 3.6 ± 0.3 µm and the width was 1.2 ± 0.2µm, with 6 to 7 turns of the polar filament. The divergences observed, regarding the morphometric and genetic structure of SSU rDNA, in relation to other Myxobolidae already described in the literature, confirm the description of the new species Myxobolus rangeli n. sp.


Assuntos
Peixes-Gato , Myxobolus , Myxozoa , Parasitos , Animais , Myxobolus/genética , Myxozoa/genética , Filogenia , Cápsulas
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