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1.
Toxicon ; 198: 121-131, 2021 Jul 30.
Article in English | MEDLINE | ID: mdl-33984369

ABSTRACT

Snakebites are considered a major neglected tropical disease, resulting in around 100,000 deaths per year. The recommended treatment by the WHO is serotherapy, which has limited effectiveness against the toxins involved in local tissue damage. In some countries, patients use plants from folk medicines as antivenoms. Aegiphila species are common plants from the Brazilian Amazon and are used to treat snakebites. In this study, leaves from Aegiphila integrifolia (Jacq) Moldenke were collected from Roraima state, Brazil and its ethanolic extract was evaluated through in vitro and in vivo experiments to verify their antiophidic activity against Bothrops atrox crude venom. The isolated compounds from A. integrifolia were analyzed and the chemical structures were elucidated on the basis of infrared, ultraviolet, mass, 1H and 1³C NMR spectrometry data. Among the described compounds, lupeol (7), betulinic acid (1), ß-sitosterol (6), stigmasterol (5), mannitol (4), and the flavonoids, pectolinarigenin (2) and hispidulin (3), were identified. The ethanolic extract and flavonoids (2 and 3) partially inhibited the proteolytic, phospholipase A2 and hyaluronidase activities of B. atrox venom, and the skin hemorrhage induced by this venom in mice. Antimicrobial activity against different bacteria was evaluated and the extract partially inhibited bacterial growth. Thus, taken together, A. integrifolia ethanolic extract has promising use as an antiophidic and antimicrobial.


Subject(s)
Anti-Infective Agents , Bothrops , Crotalid Venoms , Snake Bites , Animals , Anti-Bacterial Agents/pharmacology , Antivenins/pharmacology , Brazil , Humans , Mice , Phytochemicals/pharmacology , Plant Extracts/pharmacology , Plant Leaves
2.
Carbohydr Polym ; 179: 341-349, 2018 Jan 01.
Article in English | MEDLINE | ID: mdl-29111060

ABSTRACT

In this work, for the first time bacterial cellulose (BC) hydrogel membranes were used for the fabrication of antimicrobial cellulosic nanocomposites by hydrothermal deposition of Cu derivative nanoparticles (i.e.Cu(0) and CuxOy species). BC-Cu nanocomposites were characterized by FTIR, SEM, AFM, XRD and TGA, to study the effect of hydrothermal processing time on the final physicochemical properties of final products. XRD result show that depending on heating time (3-48h), different CuxOy phases were achieved. SEM and AFM analyses unveil the presence of the Cu(0) and copper CuxOy nanoparticles over BC fibrils while the surface of 3D network became more compact and smother for longer heating times. Furthermore, the increase of heating time placed deleterious effect on the structure of BC network leading to decrease of BC crystallinity as well as of the on-set degradation temperature. Notwithstanding, BC-Cu nanocomposites showed excellent antimicrobial activity against E. coli, S. aureus and Salmonella bacteria suggesting potential applications as bactericidal films.


Subject(s)
Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Cellulose/chemistry , Copper/chemistry , Nanocomposites/chemistry , Anti-Infective Agents/chemistry , Escherichia coli/drug effects , Gluconacetobacter/metabolism , Hot Temperature , Metal Nanoparticles/chemistry , Salmonella enterica/drug effects , Staphylococcus aureus/drug effects , Thermogravimetry , Time Factors , Water/chemistry
3.
Pesqui. vet. bras ; 34(supl.1): 34-38, dez. 2014. tab
Article in Portuguese | LILACS, VETINDEX | ID: lil-778346

ABSTRACT

Para estudar os fatores anatomofisiológicos que interferem na qualidade de complexos cumulus-oócitos (CCOs) bovinos, foram obtidas 396 ovários após abate de 198 fêmeas Bos indicus em frigorífico. Os ovários foram separados por categorias, sendo distribuídos em nulípara vs multípara e com progesterona (P4 - presença de corpo lúteo em um dos ovários) vs sem progesterona (NP4 - ausência de corpo lúteo). Todos os folículos foram mensurados e categorizados em pequenos (<6mm), médios (6 a 9mm) ou grandes (>9mm). Em seguida todos os folículos foram puncionados e os CCOs recuperados e avaliados morfologicamente. Não houve diferença na taxa de recuperação nem na qualidade dos CCOs de fêmeas nulíparas vs multíparas. O percentual de CCOs desnudos/degenerados foi maior no grupo NP4 e os CCOs expandidos foram superiores no grupo P4. A taxa de recuperação e o percentual de CCOs selecionados para PIV (graus I e II) foram similares nos grupos P4 vs NP4. Folículos pequenos apresentam menor taxa de recuperação em comparação aos de tamanho médio e grande, porém o percentual de CCOs de grau I foi superior em folículos pequenos e médios. Diante dos resultados aqui encontrados conclui-se que a categoria da doadora e a progesterona não influenciaram a qualidade de CCOs selecionados para PIV e que folículos menores apresentam de CCOs de melhor qualidade.(AU)


To study the anatomical and physiological factors that affect the bovine cumulus-oocyte complexes (COCs) quality, were examined 396 ovaries obtained after slaughter of 198 Bos indicus females. Ovaries were categorized in nulliparous vs multiparous and progesterone (P4 - a corpus luteum at least one ovary) vs without progesterone (NP4 - absence of corpus luteum). All follicles were measured and categorized into small (<6mm), medium (6 to 9mm) or large (>9mm). Then all follicles were punctured and COCs recovered and assessed morphologically. There was no difference in COCs recovery rate or quality from nulliparous vs multiparous females. The rate of denuded or degenerated oocytes was higher in NP4 and expanded COCs were higher in P4. The COCs recovery and grades I and II rates were similar in P4 vs NP4 groups. Small follicles have lower COCs recovery rate than medium or large follicles, but the grade I oocytes rates was higher in small and medium follicles. In conclusion, the category of donor female and progesterone did not affect the quality of COCs selected for PIV and smaller follicles present best quality of COCs.(AU)


Subject(s)
Animals , Female , Cattle , Oocytes , Progesterone/analysis , Cumulus Cells , Ovarian Follicle , Selection, Genetic
4.
J Econ Entomol ; 105(6): 1979-81, 2012 Dec.
Article in English | MEDLINE | ID: mdl-23356061

ABSTRACT

Hymenopteran parasitoids have been shown to be of potential value in tick biocontrol. Tick parasitoids has been reported only once in Brazil, over 95 yr ago when Ixodiphagus hookeri (Howard) was reported parasitizing Rhipicephalus sanguineus (Latreille) nymphs in Rio de Janeiro. Herein, we report the occurrence of Ixodiphagus spp. in ticks from three different regions of Brazil. In the state of Maranhão, in northeastern Brazil, parasitoids were detected in R. sanguineus nymphs on three occasions, during August 2009 and September 2010 (dry season), and January 2011 (rainy season). All parasitoids found in northeastern Brazil were identified as I. hookeri. In the state of Mato Grosso do Sul (west-central Brazil), one Amblyomma sp. engorged nymph was shown to be parasitized by I. hookeri. In the state of Rondônia (northern Brazil), one Amblyomma sp. engorged nymph was parasitized by Ixodiphagus texanus (Howard). Because Ixodiphagus spp. are present in ecologically distinct and geographically distant areas of Brazil, they are of potential use for biocontrol in the country.


Subject(s)
Host-Parasite Interactions , Rhipicephalus sanguineus/parasitology , Wasps/physiology , Animals , Brazil , Dogs , Nymph/parasitology
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