80 research outputs found
Synergistic mutual potentiation of antifungal activity of Zuccagnia punctata Cav. and Larrea nitida Cav. extracts in clinical isolates of Candida albicans and Candida glabrata
Background: Zuccagnia punctata Cav. (Fabaceae) and Larrea nitida Cav. (Zygophyllaceae) are indistinctly or jointly used in traditional medicine for the treatment of fungal-related infections. Although their dichloromethane (DCM) extract have demonstrated moderate antifungal activities when tested on their own, antifungal properties of combinations of both plants have not been assessed previously. Purpose: The aim of this study was to establish with statistical rigor whether Z. punctata (ZpE) and L. nitida DCM extract (LnE) interact synergistically against the clinically important fungi Candida albicans and Candida glabrata and to characterize the most synergistic combinations. Study design: For synergism assessment, the statistical-based Boik's design was applied. Eight ZpEâLnE fixed-ratio mixtures were prepared from four different months of 1 year and tested against Candida strains. LÏ (Loewe index) of each mixture at different fractions affected (Ï) allowed for the finding of the most synergistic combinations, which were characterized by HPLC fingerprint and by the quantitation of the selected marker compounds. Methods: LÏ and confidence intervals were determined in vitro with the MixLow method, once the estimated parameters from the doseâresponse curves of independent extracts and mixtures, were obtained. Markers (four flavonoids for ZpE and three lignans for LnE) were quantified in each extract and their combinations, with a valid HPLCâUV method. The 3D-HPLC profiles of the most synergistic mixtures were obtained by HPLCâDAD. Results: Three over four IC50ZpE/IC50LnE fixed-ratio mixtures displayed synergistic interactions at effect levels Ï > 0.5 against C. albicans. The dosis of the most synergistic (LÏ = 0.62) mixture was 65.96 ”g/ml (ZpE = 28%; LnE = 72%) containing 8 and 36% of flavonoids and lignans respectively. On the other hand, one over four IC50ZpE/IC50LnE mixtures displays synergistic interactions at Ï > 0.5 against C. glabrata. The dosis of the most synergistic (LÏ = 0.67) mixture was 168.23 ”g/ml (ZpE = 27%; LnE = 73%) with 9.7 and 31.6% of flavonoids and lignans respectively. Conclusions: Studies with the statistical-based MixLow method, allowed for the finding of the most ZpEâLnE synergistic mixtures, giving support to a proper joint use of both antifungal herbs in traditional medicine.Fil: Butassi, EstefanĂa. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Svetaz, Laura Andrea. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Ivancovich, Juan J.. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas; ArgentinaFil: Feresin, Gabriela Egly. Universidad Nacional de San Juan. Facultad de IngenierĂa. Instituto de BiotecnologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Tapia, Alejandro A.. Universidad Nacional de San Juan. Facultad de IngenierĂa. Instituto de BiotecnologĂa; ArgentinaFil: Zacchino, Susana Alicia Stella. Universidad Nacional de Rosario. Facultad de Ciencias BioquĂmicas y FarmacĂ©uticas; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
AnĂĄlise do efeito de nanopartĂculas de prata contra cĂ©lulas aderidas e biofilmes de Candida albicans e Candida glabrata
O aumento na resistĂȘncia dos biofilmes de Candida Ă terapia antifĂșngica convencional
tem despertado o interesse no uso da prata como um agente antimicrobiano. Assim, o objetivo
deste trabalho foi avaliar a eficĂĄcia antifĂșngica de nanopartĂculas de prata (NPs) contra cĂ©lulas
aderidas e biofilmes de Candida albicans e Candida glabrata. Métodos: NPs esféricas (5 nm)
foram sintetizadas atravĂ©s da redução do nitrato de prata pelo citrato de sĂłdio. Testes de mĂnima
concentração inibitória (MCI) foram realizados para as duas espécies de Candida de acordo com o
método da microdiluição. NPs foram aplicadas sobre células aderidas (2 hrs) e biofilmes (48 hrs),
e após 24 horas de contato os biofilmes resultantes foram caracterizados através da contagem do
nĂșmero de unidades formadoras de colĂŽnias (UFCs) e quantificação da biomassa total. Resultados:
Os valores de MCI para C. glabrata foram maiores (0,4 â 3,3 ”g/mL) do que para C. albicans
(0,4 â 1,6 ”g/mL). NPs foram mais efetivas na redução da biomassa total quando aplicadas sobre
células aderidas do que sobre biofilmes pré-formados. NPs também foram altamente efetivas na
redução das UFCs quando aplicadas sobre as células aderidas de C. glabrata (~70%) e respectivos
biofilmes (~50%). Para as cepas de C. albicans o efeito não foi tão notório, mas também existiu
uma redução no nĂșmero de UFCs. ConclusĂŁo: NPs apresentam potencial como agente antifĂșngico
alternativo no controle de infecçÔes por espécies de Candida
Suicide and suicides attempts in Italian prison epidemiological findings from the âTrivenetoâ area, 2010-2016
The aim of this observational study was to assess rates of suicide and suicide attempts, in relation to gender, age, place of birth and security levels, in north-eastern Italian prisons during 2010-2016, and investigate associations with prison overcrowding, offence type and prior self-harm and suicide attempts. The study was based on individual data on suicides and suicide attempts from 16 prisons, with an average yearly number of 3,900 inmates during the study period, for all prisons combined. Descriptive and binomial regression analyses were performed.
Rates of suicide and suicide attempts in Triveneto prisons were 1and 15 per 1,000 inmates, respectively. More than 90% of suicides and suicide attempters were men aged between 21 and 49 years old, and most had committed violent offences. Only half the prisoners who died by suicide and 30% of those who made a suicide attempt in custody were Italians. âCooperative witnessesâ had the highest mean suicide attempt rate (30/1,000 inmates). Fourteen per cent of suicides and 19% of attempters had a prior history of suicide attempts and self-injury. In binomial regression analyses, predictors of suicidal behaviour were being a male inmate in standard security conditions, with a mean age of 30 years.
The study highlighted that there is a need for suicide prevention policies in Triveneto; these should take into account predictors of suicidal behaviours and individual characteristics of suicidal inmates. More research is warranted in order to both evaluate the effectiveness of prevention plans and better assess risk of suicide in specific groups, such as cooperative witnesses
Alkaloids Analysis of Habranthus cardenasianus (Amaryllidaceae), Anti-Cholinesterase Activity and Biomass Production by Propagation Strategies
Plants in the Amaryllidaceae family synthesize a diversity of bioactive alkaloids. Some of these plant species are not abundant and have a low natural multiplication rate. The aims of this work were the alkaloids analysis of a Habranthus cardenasianus bulbs extract, the evaluation of its inhibitory activity against cholinesterases, and to test several propagation strategies for biomass production. Eleven compounds were characterized by GC-MS in the alkaloid extract, which showed a relatively high proportion of tazettine. The known alkaloids tazettine, haemanthamine, and the epimer mixture haemanthidine/6-epi-haemanthidine were isolated and identified by spectroscopic methods. Inhibitory cholinesterases activity was not detected. Three forms of propagation were performed: bulb propagation from seed, cut-induced bulb division, and micropropagated bulbs. Finally, different imbibition and post-collection times were evaluated in seed germination assays. The best propagation method was cut-induced bulb division with longitudinal cuts into quarters (T1) while the best conditions for seed germination were 0-day of post-collection and two days of imbibition. The alkaloids analyses of the H. cardenasianus bulbs showed that they are a source of anti-tumoral alkaloids, especially pretazettine (tazettine) and T1 is a sustainable strategy for its propagation and domestication to produce bioactive alkaloids. Keywords: Amaryllidaceae; bioactive alkaloids; GC-MS; propagation methods; biomass productio
Effects of Obesity on Bone Mass and Quality in Ovariectomized Female Zucker Rats
Obesity and osteoporosis are two chronic conditions that have been increasing in prevalence. Despite prior data supporting the positive relationship between body weight and bone mineral density (BMD), recent findings show excess body weight to be detrimental to bone mass, strength, and quality. To evaluate whether obesity would further exacerbate the effects of ovariectomy on bone, we examined the tibiae and fourth lumbar (L4) vertebrae from leptin receptor-deficient female ( / ) Zucker rats and their heterozygous lean controls ( /+ ) that were either sham-operated or ovariectomized (Ovx). BMD of L4 vertebra was measured using dual-energy X-ray absorptiometry, and microcomputed tomography was used to assess the microstructural properties of the tibiae. Ovariectomy significantly ( < 0.001) decreased the BMD of L4 vertebrae in lean and obese Zucker rats. Lower trabecular number and greater trabecular separation ( < 0.001) were also observed in the tibiae of lean-and obese-Ovx rats when compared to sham rats. However, only the obese-Ovx rats had lower trabecular thickness (Tb.Th) ( < 0.005) than the other groups. These findings demonstrated that ovarian hormone deficiency adversely affected bone mass and quality in lean and obese rats while obesity only affected Tb.Th in Ovx-female Zucker rats
âAcciĂłn de la ingesta de aceite de pistacho en un modelo animal transgĂ©nico para la enfermedad de alzheimerâ.
La Enfermedad de Alzheimer (EA) es una enfermedad neurodegenerativa crĂłnica, queconduce a demencia, y es de alta mĂĄs prevalencia en personas mayores a 65 años.Diversos estudios han vinculado una amplia gama de factores como la dieta y el estilo devida con un mayor o menor riesgo de padecer esta enfermedad. Existen evidenciarespecto a que el daño oxidativo neuronal es uno de los primeros cambios observadoscuando se lo compara con otros aspectos caracterĂsticos de la patologĂa. Por ello, elestrĂ©s oxidativo ha sido postulado como uno de los factores causales de la EA, siendolas zonas de la corteza cerebral y el hipocampo las principalmente afectadas.Particularmente, la enzima Ăłxido nĂtrico sintasa (NOS) en sus 3 isoformas es la fuenteprincipal del Ăłxido nĂtrico (NO); una molĂ©cula pequeña, que cumple diferentes funcionesen el organismo, desde actuar como neurotransmisor a controlar la transcripciĂłn dealgunos genes. Sin embargo, niveles alterados de NO pueden ser perjudiciales para elorganismo, dado que contribuyen en una variedad de patologĂas neurodegenerativas,como la esclerosis mĂșltiple, la enfermedad de Parkinson y la EA
Penetratin and Derivatives Acting as Antibacterial Agents
The synthesis, in vitro evaluation and conformational study of penetratin and structurally related derivatives acting as antibacterial agents are reported. Among the compounds evaluated here, two methionine sulphoxide derivatives (RQIKIWFQNRRM[O]KWKK-NH2 and RQIKIFFQNRRM[O]KFKK-NH2) exhibited the strongest antibacterial effect in this series. In order to better understand the antimicrobial activity obtained for these peptides, we performed an exhaustive conformational analysis using different approaches. Molecular dynamics simulations were performed using two different media (water and trifluoroethanol/water). The results of these theoretical calculations were corroborated using experimental CD measurements. The electronic study for these peptides was carried out using molecular electrostatic potentials obtained from RHF/6-31G(d) calculations. In addition, the non-apeptide RQIRRWWQR-NH2 showed strong inhibitory action against the Gram-negative and Gram-positive bacteria tested in this study
Dispersion and release of embelin from electrospun biodegradable, polymeric, membranes
In this work, microfiber meshes containing embelin, a poorly water-soluble bioactive agent, were prepared by solubilizing embelin in a biodegradable and biocompatible polymer matrix of poly(Δ-caprolactone) (PCL). Plain or drug-loaded, highly porous, fibrous membranes with a high area-to-volume ratio were obtained by electrospinning. Non-woven microfibrous meshes were formed by uniform bead-free fibers with a mean diameter of 1.2âÎŒm. Non-porous films were obtained by solution casting, and were used for comparison. The drug-loading content of the prepared systems was appropriate for topical applications. The thermal properties revealed that the crystallinity of embelin significantly decreased, the drug having almost completely dissolved in the PCL fibers. The in situ bioavailability of embelin, an antimycotic agent, is an important aspect to consider in topical drug applications. The drug-loaded systems presented different contact areas with the biological environment. When comparing the ability to expose embelin with the biological environment of the prepared systems, drug-loaded fibrous scaffolds showed a higher bioavailability of the bioactive agent because of an increase by 86% in the area-to-volume ratio, providing an effective area per unit mass that was 5.8-fold higher than that of the film. For the meshes, 90% embelin release was observed after 12h of exposure to phosphate-buffered saline, whereas for the films a comparable level of release occurred only after 72h.Fil: Cortez Tornello, Pablo Roberto. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Mar del Plata. Instituto de InvestigaciĂłn En Ciencia y TecnologĂa de Materiales (i); Argentina. Universidad Nacional de San Juan. Facultad de IngenierĂa. Instituto de BiotecnologĂa; ArgentinaFil: Feresin, Gabriela Egly. Universidad Nacional de San Juan. Facultad de IngenierĂa. Instituto de BiotecnologĂa; ArgentinaFil: Tapia, Alejandro. Universidad Nacional de San Juan. Facultad de IngenierĂa. Instituto de BiotecnologĂa; ArgentinaFil: Veiga, Itiara G.. Universidade Estadual de Campinas; BrasilFil: Moraes, Ăngela M.. Universidade Estadual de Campinas; BrasilFil: Abraham, Gustavo Abel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Mar del Plata. Instituto de InvestigaciĂłn En Ciencia y TecnologĂa de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de IngenierĂa; ArgentinaFil: Cuadrado, Teresita Raquel. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Mar del Plata. Instituto de InvestigaciĂłn En Ciencia y TecnologĂa de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de IngenierĂa; Argentin
Entanglement of Imaging and Imagining of Nanotechnology
Images, ranging from visualizations of the nanoscale to future visions, abound within and beyond the world of nanotechnology. Rather than the contrast between imaging, i.e. creating images that are understood as offering a view on what is out there, and imagining, i.e. creating images offering impressions of how the nanoscale could look like and images presenting visions of worlds that might be realized, it is the entanglement between imaging and imagining which is the key to understanding what images do. Three main arenas of entanglement of imag(in)ing and the tensions involved are discussed: production practices and use of visualizations of the nanoscale; imag(in)ing the future and the present; and entanglements of nanoscience and art. In these three arenas one sees struggles about which images might stand for nanotechnology, but also some stabilization of the entanglement of imag(in)ing, for example in established rules in the practices of visualizing the nanoscale. Three images have become iconic, through the combination of their wide reception and further circulation. All three, the IBM logo, the Foresight Instituteâs Nanogear image, and the so-called Nanolouse, depict actual or imagined technoscientific objects and are thus seen as representing technoscientific achievements â while marking out territory
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