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1.
Sci Rep ; 14(1): 15289, 2024 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-38961137

RESUMO

The limited availability of antivirals for new highly pathogenic strains of virus has become a serious public health. Therefore, news products against these pathogens has become an urgent necessity. Among the multiple sources for news antibiotics and antivirals, insect exudates or their products has become an increasingly frequent option. Insects emerged 350 million years ago and have showed a high adaptability and resistance to the most varied biomes. Their survival for so long, in such different environments, is an indication that they have a very efficient protection against environmental infections, despite not having a developed immune system like mammals. Since the ancient civilizations, the products obtained from the bee have been of great pharmacological importance, being used as antimicrobial, anti-inflammatory, antitumor and several other functions. Investigations of biological activity of propolis have been carried out, mainly in the species Apis mellifera, and its product have showed activity against some important viruses. However, for the Meliponini species, known as stingless bees, there are few studies, either on their chemical composition or on their biological activities. The importance of studying these bees is because they come from regions with native forests, and therefore with many species of plants not yet studied, in addition to which they are regions still free of pesticides, which guarantees a greater fidelity of the obtained data. Previous studies by our group with crude hydroalcoholic extract of propolis demonstrated an intense antiviral activity against Herpes, influenza, and rubella viruses. In this work, we chose to use aqueous extracts, which eliminates the presence of other compounds besides those originally present in propolis, in addition to extracting substances different from those obtained in alcoholic extracts. Therefore, this study aimed to identify, isolate and characterize compounds with antiviral effects from aqueous propolis extracts from Scaptotrigona aff postica, in emerging viruses such as zicavirus, chikungunya, and mayaro virus. The evaluation of the antiviral activity of the crude and purified material was performed by reducing infectious foci in VERO cell cultures. The results obtained with crude propolis, indicate a high reduction of zica virus (64×) and mayaro (128×) when was used 10% v/v of propolis. The reduction of chikungunya virus was of 256 fold, even when was used 5% v/v of propolis. The chemical characterization of the compounds present in the extracts was performed by high-pressure liquid chromatography. Through the purification of propolis by HPLC and mass spectrometry, it was possible to identify and isolate a peak with antiviral activity. This substance showed activity against all viruses tested. When purified fraction was used, the reduction observed was of 16 fold for zicavirus, 32 fold for mayaro virus and 512 fold for chikungunya virus. Likewise, it was observed that the antiviral response was concentration dependent, being more intense when propolis was added 2 h after the viral infection. Now we are carrying out the chemical characterization of the purified compounds that showed antiviral action.


Assuntos
Antivirais , Própole , Própole/farmacologia , Própole/química , Animais , Antivirais/farmacologia , Antivirais/química , Abelhas , Vírus Chikungunya/efeitos dos fármacos , Chlorocebus aethiops , Células Vero
2.
J Helminthol ; 97: e58, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37476963

RESUMO

Marmosa constantiae is a species of marsupial restricted to the central portion of South America. In Brazil, it occurs in the northwestern region including five states of the Amazon, Cerrado, and Pantanal biomes. However, there is no study of the helminth fauna or helminth community structure for this marsupial. The aims of this study were to describe the species composition and to analyse the structure of the helminthic community of M. constantiae in an area of the Amazon Arc in Sinop, north of the state of Mato Grosso, Brazil. Parasites were searched in 53 specimens of this marsupial, among which 44 were infected with at least one helminth species. Parasitic helminths were counted and identified. Nine species were collected: seven nematodes, one cestode, and one acanthocephalan. The most abundant species were Gracilioxyuris agilisis, Travassostrongylus scheibelorum, Pterygodermatites sinopiensis, and Subulura eliseae. These species were the only dominant ones in the component community. No significant differences were observed in the abundance and prevalence of helminths between male and female hosts. Host body size significantly influenced helminth abundance in males. The pattern of community structure considering the infracommunities in this locality indicated more species replacement than species loss along the environmental gradient. This is the first study to report the helminth fauna and the helminth community structure of M. constantiae.


Assuntos
Helmintíase Animal , Helmintos , Marsupiais , Feminino , Masculino , Camundongos , Animais , Brasil/epidemiologia , Helmintíase Animal/epidemiologia , Helmintíase Animal/parasitologia , Gambás/parasitologia
3.
J Helminthol ; 96: e60, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35942907

RESUMO

The parasite biodiversity of mouse opossums in Brazil remains incompletely explored. We describe a new species of Subulura (Ascaridida: Subuluroidea) from the large intestine of the white-bellied woolly mouse opossum, Marmosa constantiae, based on the results of light and scanning electron microscopy (SEM). We also partially sequenced the mitochondrial cytochrome c oxidase I (MT-CO1) gene of the new species, using molecular phylogenetic analyses to determine its relationships within the Subuluroidea superfamily. As molecular data on subuluroid species are extremely limited, few inferences could be drawn from our phylogenies. Our SEM observations showed the detailed morphology of the cephalic extremity, precloacal pseudo-sucker, caudal papillae, phasmids and vulva. Subulura eliseae sp. n. differs from the other four Subulura parasites species of marsupials by the number of caudal papillae and the structure dimensions, and size of the spicule. Moreover, S. eliseae sp. n. has ten pairs of caudal papillae, which is unique compared to other species. We present morphometric and molecular data on this new species, contributing to future studies on subuluroids.


Assuntos
Ascaridídios , Parasitos , Animais , Brasil , Feminino , Camundongos , Gambás , Filogenia , Floresta Úmida
4.
Med Oral Patol Oral Cir Bucal ; 27(3): e285-e293, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35368009

RESUMO

BACKGROUND: Pediatric head and neck cancer (PHNC) is rare and its nonspecific clinical manifestations may often lead to delayed diagnosis. We aimed to describe the signs, symptoms, and clinicopathological characteristics of PHNC. MATERIAL AND METHODS: Medical records were retrospectively reviewed for all PHNC cases diagnosed from 1986 to 2016 affecting patients aged 19-years and younger from a tertiary referral center in Brazil. Demographic variables, anatomical site of primary tumors, histopathological diagnoses, signs and symptoms, and patterns of misdiagnosis were collected and interpreted by statistical and descriptive analysis. RESULTS: A total of 253 PHNC cases were included. The mean age was 9.3 years and male patients were more frequently affected (60.9%). Burkitt lymphoma (23.7%), nasopharyngeal carcinoma (15.8%), and rhabdomyosarcoma (15.4%) were the most common cancer types. The nasopharynx (28.9%), cervical/lymph node region (25.3%), and craniofacial bones (8.3%) were the predominant anatomical sites. Tumor/swelling (68.4%), was the clinical finding often presented. The univariable analysis showed association between tumor histology and clinical variables such as sex (p=0.022), age (p<0.0001), anatomical location (p<0.0001) tumor/swelling (p=0.034), pain (p=0.031), systemic/general manifestations (p=0.004), nasal/breathing alterations (p=0.012), orbital/ocular alterations (p<0.0001). Misdiagnosis such as tonsillitis, otitis, and abscess were frequent. CONCLUSIONS: Although the clinical findings of PHNC are often unspecific, this study provided signs and symptoms with significant correlations between tumor histology. The suspicion of malignancy should be considered when the main signs and symptoms reported here appear and persist, in order to conduct a timely diagnosis.


Assuntos
Neoplasias de Cabeça e Pescoço , Rabdomiossarcoma , Brasil/epidemiologia , Criança , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/epidemiologia , Humanos , Masculino , Pescoço , Estudos Retrospectivos , Rabdomiossarcoma/diagnóstico , Rabdomiossarcoma/epidemiologia
7.
J Microsc ; 277(2): 93-99, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31997353

RESUMO

Following the first and second generations, the challenge in obtaining a better balance between strength and elongation is still the main characteristic of the third generation of advanced high-strength steels (AHSS). With this, the use of multiphase microstructures has increased over the last few years. It can be difficult to characterize all the phases with only optical microscopy (OM), so the use of scanning electron microscopy (SEM) is essential for accuracy in cases where researchers lack experience. To expand the possibilities, this research proposed a new approach that would allow experienced researchers to characterize multiphase steels using only OM. A high silicon steel was austempered slightly below martensite start (Ms) temperature for three different time periods in order to obtain different quantities of martensite, bainite and retained austenite. X-ray diffraction was carried out in order to confirm and obtain retained austenite volume fractions, and the results indicated that shorter holding times were not enough to enrich and stabilize retained austenite. Then, each samples was etched with four different etchants. Results showed that the new multiple etchings methodology (MEM) allowed a better visualization of all the phases when viewed together. Beraha martensitc revealed nontempered martensitic microstructures. Sodium metabisulfite revealed retained austenite. LePera and Nital were the best at revealing the evolution of the microstructure over time, even with the changes which occurred due to martensite tempering. SEM images confirmed the results obtained via MEM. LAY DESCRIPTION: For improving safety, environmental protection, mechanical resistance and others issues, many different steel grades have been studied. These grades were named depending on their mechanical properties. The current generation is the third, which is still searching for one of the main antagonists in material science: the best balance between mechanical resistance (how strong it is) and elongation (how long it can be stretched to). In order to achieve this goal, many researchers are studying variations in the production processes. During production, the materials are able to internally change their basic microstructure, named phases. In the past, steels were usually produced to have only a few phases. Today's advanced high strength steels (AHSS) can have many. Each of these phases has its own characteristics. The main focus of this research was to give a new way of identify these phases using an optical microscope. For revealing these phases, etchants are normally used. The etchants used in this research are capable of tinting each of these phases with a different colour or tone. So the purpose of this work was to suggest a new approach in order to allow for more precise identification of the phases in the steel. The results were positive, showing that looking at the samples as a whole is better than the traditional methods. Also, different etchants' characteristics were observed during the changes obtained by this work's chosen processes.

8.
Nutr Metab Cardiovasc Dis ; 29(1): 69-78, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30459074

RESUMO

BACKGROUND AND AIMS: Polyphenol-rich diets have been associated with reduced risk of cardiovascular disease (CVD). However, few prospective epidemiological studies have examined the relationship between classes of ingested polyphenols and risk of CVD. Our aim was to evaluate the association between polyphenol intake and risk of major cardiovascular events in a prospective Spanish cohort. METHODS AND RESULTS: We included 17,065 university graduates (60.7% women, mean age: 37.2 years, age range: 20-89) followed-up for a mean of 10.1 years. Polyphenol intake was assessed at baseline using a validated semi-quantitative 136-item food frequency questionnaire and matching food consumption data with the Phenol-Explorer database. Cox proportional hazards models were used to estimate the adjusted hazard ratios (HR) and 95% confidence intervals (95% CI) for incident cardiovascular events (myocardial infarction, stroke or cardiovascular death). Cherries, chocolate, coffee, apples, and olives were the major sources of variability in polyphenol intake. Participants with higher flavonoids intake (fifth quintile) had a 47% lower incidence of cardiovascular events compared to those in the lowest quintile (HR: 0.53, 95% CI: 0.29-0.98; P for trend = 0.09) after adjusting for potential confounders. The results were non-significant for other polyphenol types. CONCLUSION: The intake of flavonoids showed an inverse association with risk of cardiovascular events in a prospective cohort of Spanish middle-aged adult university graduates. REGISTRATION NUMBER FOR CLINICAL TRIALS: NCT02669602 in Clinical Trials.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Dieta , Polifenóis/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Inquéritos sobre Dietas , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polifenóis/classificação , Estudos Prospectivos , Fatores de Proteção , Fatores de Risco , Espanha/epidemiologia , Estudantes , Fatores de Tempo , Universidades , Adulto Jovem
9.
Braz. j. biol ; 78(3): 436-442, Aug. 2018. tab, graf
Artigo em Inglês | LILACS | ID: biblio-951571

RESUMO

Abstract In this study were evaluated the anaesthesia and analgesic effects of clove Eugenia caryophyllata, tea tree Melaleuca alternifolia and basil Ocimum basilicum essential oils (EO) during handling of yellowtail clownfish Amphiprion clarkii. Juveniles (3.70 ± 0.75 cm and 1.03 ± 0.50 g; mean ± standard deviation) were submitted to concentrations of 40, 50, 60, 70 and 80 µl L-1 of clove, 150, 200, 250, 300 and 350 µl L-1 of basil and 200, 300, 400, 500 and 600 µl L-1 of tea tree oils (n=10/concentration), previously defined in pilot tests. Individually and only once, fish from each treatment were placed in a glass recipient containing 1 L of seawater at a temperature of 25 °C, salinity of 35 g L-1 and the specific concentration of diluted EO (stock solution). Control (only seawater) and blank (seawater and ethanol at the highest concentration used to dilute the oils) treatments were also conducted. After reaching the stage of surgical anaesthesia, fish were submitted to biometry and a sensibility test. After that, they were transferred to clean seawater for anaesthesia recovery. The times of induction needed to reach each anaesthesia stage and anaesthesia recovery were recorded. Animals were observed for 72 hours after the procedures. All the EO provoked anaesthesia and analgesic effects in A. clarkii, but basil oil is not recommended because it caused involuntary muscle contractions and mortality in 100% and 12% of fish, respectively. The lower concentrations that promote suitable induction and recovery times are 50 µl L-1 of clove oil and 500 µl L-1 of tea tree oil. However, due to its complementary high analgesic efficiency, clove oil is recommended as the ideal anaesthetic for A. clarkii.


Resumo Neste estudo foram avaliados os efeitos anestésicos e analgésicos dos óleos essenciais (OE) de cravo Eugenia caryophyllata, melaleuca Melaleuca alternifolia e manjericão Ocimum basilicum durante manejo de peixes-palhaços Amphiprion clarkii. Juvenis (3.70 ± 0.75 cm e 1.03 ± 0.50 g; média ± desvio padrão) foram submetidos às concentrações de 40, 50, 60, 70 e 80 µl L-1 de cravo, 150, 200, 250, 300 e 350 µl L-1 de manjericão e 200, 300, 400, 500 e 600 µl L-1 de melaleuca (n=10/concentração), previamente definidas em testes pilotos. Individualmente e somente uma vez, os peixes de cada tratamento foram colocados em recipiente de vidro contendo 1 L de água salgada, em temperatura de 25 °C, salinidade de 35 g L-1 e a concentração específica de OE diluída (solução estoque). Tratamentos controle (apenas água marinha) e branco (água marinha e a maior concentração de etanol utilizada para diluição dos óleos) também foram conduzidos. Após atingirem o estágio de anestesia cirúrgica, os peixes foram submetidos à biometria e teste de sensibilidade. Em seguida, foram transferidos para água marinha limpa. Os tempos necessários para atingir cada estágio anestésico e recuperação foram registrados. Os animais foram observados por 72 horas após os procedimentos. Todos os OE provocaram anestesia e analgesia em A. clarkii, porém o óleo de manjericão não é recomendado, pois causou contrações musculares involuntárias e mortalidade em 100% e 12% dos animais, respectivamente. As menores concentrações que promovem indução anestésica e recuperação em tempos adequados são 50 µl L-1 de óleo de cravo e 500 µl L-1 de óleo de melaleuca. Entretanto, devido à sua alta eficiência analgésica complementar, o óleo de cravo é recomendado como o anestésico ideal para A. clarkii.


Assuntos
Animais , Óleos de Plantas/toxicidade , Óleos Voláteis/farmacologia , Óleo de Melaleuca/farmacologia , Óleo de Cravo/farmacologia , Analgesia/veterinária , Analgésicos/farmacologia , Anestesia/veterinária , Anestésicos/farmacologia , Especificidade da Espécie , Óleos de Plantas/efeitos adversos , Relação Dose-Resposta a Droga , Peixes , Analgesia/métodos , Anestesia/métodos , Contração Muscular/efeitos dos fármacos
10.
Amino Acids ; 50(5): 503-511, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29305745

RESUMO

The biomembrane natural (NRL-Natural Rubber Latex), manipulated from the latex obtained from the rubber tree Hevea brasiliensis, has shown great potential for application in biomedicine and biomaterials. Reflecting the biocompatibility and low bounce rate of this material, NRL has been used as a physical barrier to infectious agents and for the controlled release of drugs and extracts. The aim of the present study was to evaluate the incorporation and release of peptides using a latex biomembrane carrier. After incorporation, the release of material from the membrane was observed using spectrophotometry. Analyses using HPLC and mass spectroscopy did not confirm the release of the antimicrobial peptide [W6]Hylin a1 after 24 h. In addition, analysis of the release solution showed new compounds, indicating the degradation of the peptide by enzymes contained in the latex. Additionally, the release of a peptide with a shorter sequence (Ac-WAAAA) was evaluated, and degradation was not observed. These results showed that the use of NRL as solid matrices as delivery systems of peptide are sequence dependent and could to be evaluated for each sequence.


Assuntos
Portadores de Fármacos , Hevea/química , Membranas Artificiais , Peptídeos , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Portadores de Fármacos/farmacologia , Avaliação Pré-Clínica de Medicamentos , Látex , Peptídeos/química , Peptídeos/farmacocinética , Peptídeos/farmacologia
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