157 research outputs found

    Optimization of the enzymatic synthesis of pentyl oleate with lipase immobilized onto novel structured support

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    The term biorefinery is related to the sustainable production of value-added bioproducts and bioenergy from biomass. Esters from fatty acids are important compounds synthesized from by-products of the oleochemical industry. In agreement with the biorefinery concept, it is important to search for catalysts that reduce the consumption of energy and water, using moderate operation conditions and low reaction times. In this work, response surface methodology (RSM) was used to optimize the enzymatic synthesis of pentyl oleate using Candida antarctica lipase B (CALB) immobilized on a polyethylene-aluminum structured support. A factorial design was employed to evaluate the effects of several parameters on the ester yield. To obtain a model with a good fit, an approach to reaction mechanism and enzyme kinetics was taken into consideration. Experimental findings were correlated and explained using equations of a ping-pong bi-bi kinetic model and considering the inhibitory effects of both substrates. The developed model was consistent with the experimental data predicting an increase in pentyl oleate production with increasing temperature and a decrease with higher oleic acid amounts and alcohol to acid molar ratios. This model could be useful in a future industrial application of CALB/LLDPE/Al to minimize the costs in oleochemical biorefineries.Fil: Cavallaro, Valeria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Planta Piloto de IngenierĂ­a QuĂ­mica. Universidad Nacional del Sur. Planta Piloto de IngenierĂ­a QuĂ­mica; Argentina. Universidad Nacional del Sur. Departamento de QuĂ­mica; ArgentinaFil: Tonetto, Gabriela Marta. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Planta Piloto de IngenierĂ­a QuĂ­mica. Universidad Nacional del Sur. Planta Piloto de IngenierĂ­a QuĂ­mica; Argentina. Universidad Nacional del Sur. Departamento de IngenierĂ­a QuĂ­mica; ArgentinaFil: Ferreira, MarĂ­a LujĂĄn. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Planta Piloto de IngenierĂ­a QuĂ­mica. Universidad Nacional del Sur. Planta Piloto de IngenierĂ­a QuĂ­mica; Argentina. Universidad Nacional del Sur. Departamento de QuĂ­mica; Argentin

    Natural AChE inhibitors from plants and their contribution to AlzheimerÂŽs disease therapy

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    As acetylcholinesterase (AChE) inhibitors are an important therapeutic strategy in Alzheimer's disease, efforts are being made in search of new molecules with anti-AChE activity. The fact that naturally-occurring compounds from plants are considered to be a potential source of new inhibitors has led to the discovery of an important number of secondary metabolites and plant extracts with the ability of inhibiting the enzyme AChE, which, according to the cholinergic hypothesis, increases the levels of the neurotransmitter acetylcholine in the brain, thus improving cholinergic functions in patients with Alzheimer's disease and alleviating the symptoms of this neurological disorder. This review summarizes a total of 128 studies which correspond to the most relevant research work published during 2006-2012 (1st semester) on plant-derived compounds, plant extracts and essential oils found to elicit AChE inhibition.Fil: Murray, Ana Paula. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; ArgentinaFil: Faraoni, María Belén. Universidad Nacional del Sur. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; ArgentinaFil: Castro, Maria Julia. Universidad Nacional del Sur. Departamento de Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; ArgentinaFil: Alza, Natalia Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; ArgentinaFil: Cavallaro, Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Bahía Blanca. Instituto de Química del Sur; Argentina. Universidad Nacional del Sur; Argentin

    Cyclolepis genistoides aqueous extract as source of neuroprotective agents

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    Since oxidative stress (OS) is a main component in neurodegenerative diseases, targeting this causative agent constitutes an important approach in drug discovery. In previous studies, we have selected the aqueous extract of Cyclolepis genistoides from a set of medicinal plants based on its ability to diminish metal-induced OS cellular markers. The aim of this work was to characterize the mechanism by which C. genistoides extract protected cells against OS. For this purpose, human neuroblastoma cells (IMR-32) were exposed to C. genistoides extract under conditions favoring OS (ferric ammonium citrate -FAC- exposure). C. genistoides extract (20 ÎŒg/mL) diminished the generation of superoxide anion in the presence of FAC. Moreover, the extract increased catalase activity when cells were exposed to FAC. Additionally, C. genistoides extract triggered the nuclear translocation of Nrf2, a cytoprotective transcription factor involved in antioxidant enzyme expression. The determination of flavonoids in C. genistoides extract revealed 16.1 ± 0.1 mg quercetin equivalents/g. To identify the bioactive components, 9 fractions (A-I) were obtained after a bio-guided fractionation. The evaluation of the main fractions F, G and H (20 ÎŒg/mL) showed that fractions F and H exposure reduced reactive oxygen species (ROS) production induced by FAC; however, fraction G treatment increased ROS levels. Until now, a sesquiterpene lactone was identified in fraction F. Our findings suggest that C. genistoides extract exerts the protective effect via the activation of cellular antioxidant defenses. Further studies are necessary to identify which compounds are responsible for the neuroprotective effect through Nrf2 modulationFil: Alza, Natalia Paola. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca. Universidad Nacional del Sur. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca; ArgentinaFil: Cavallaro, Valeria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de QuĂ­mica del Sur. Universidad Nacional del Sur. Departamento de QuĂ­mica. Instituto de QuĂ­mica del Sur; ArgentinaFil: Benzi Juncos, Oriana Nicole. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca. Universidad Nacional del Sur. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca; ArgentinaFil: Murray, Ana Paula. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de QuĂ­mica del Sur. Universidad Nacional del Sur. Departamento de QuĂ­mica. Instituto de QuĂ­mica del Sur; ArgentinaFil: Salvador, Gabriela Alejandra. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca. Universidad Nacional del Sur. Instituto de Investigaciones BioquĂ­micas de BahĂ­a Blanca; Argentina7th International Electronic Conference on Medicinal ChemistryBaselBĂ©lgicaSciforu

    Synchronous liver and peritoneal metastases from colorectal cancer: Is cytoreductive surgery and hyperthermic intraperitoneal chemotherapy combined with liver resection a feasible option?

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    BackgroundTraditionally, synchronous liver resection (LR), cytoreductive surgery (CRS), and hyperthermic intraperitoneal chemotherapy for colorectal liver and peritoneal metastases have been contraindicated. Nowadays, clinical practice has promoted this aggressive treatment in selected cases. This study aimed to review surgical and survival results of an extensive surgical approach including CRS with hyperthermic intraperitoneal chemotherapy (HIPEC) and LR. MethodsPubMed, EMBASE, and Web of Science databases were matched to find the available literature on this topic. The search period was limited to 10 years (January 2010-January 2021). A threshold of case series of 10 patients or more was applied. ResultsIn the search period, out of 114 studies found about liver and peritoneal metastases from colorectal cancer, we found 18 papers matching the inclusion criteria. Higher morbidity and mortality were reported for patients who underwent such an extensive surgical approach when compared with patients who underwent only cytoreductive surgery and HIPEC. Also, survival rates seem worse in the former than in the latter. ConclusionThe role of combined surgical strategy in patients with synchronous liver and peritoneal metastases from colorectal cancer remains controversial. Survival rates and morbidity and mortality seem not in favor of this option. A more accurate selection of patients and more restrictive surgical indications could perhaps help improve results in this subgroup of patients with limited curative options

    Clinanthus microstephium, an Amaryllidaceae species with Cholinesterase Inhibitor Alkaloids: Structure−Activity analysis of Haemanthamine skeleton derivatives

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    Plants of the Amaryllidaceae family are well-known (not only) for their ornamental value but also for the alkaloids that they produce. In this report, the first phytochemical study of Clinanthus genus was carried out. The chemical composition of alkaloid fractions from Clinanthus microstephium was analyzed by GC/MS and NMR. Seven known compounds belonging to three structural types of Amaryllidaceae alkaloids were identified. An epimeric mixture of a haemanthamine-type compound (6-hydroxymaritidine) was tested as an inhibitor against acetyl- and butyrylcholinesterase enzymes (AChE and BChE, respectively), two enzymes relevant in the treatment of Alzheimer's disease, with good results. Structure–activity relationships through molecular docking studies with this alkaloid and other structurally related compounds were discussed.Fil: Adessi CofrĂ©, Tonino Graziano. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂ­a Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Instituto Multidisciplinario de BiologĂ­a Vegetal; ArgentinaFil: Borioni, JosĂ© Luis. Universidad Nacional de Cuyo. Facultad de Ciencias Exactas y Naturales; Argentina. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica; ArgentinaFil: Pigni, Natalia Belen. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Ciencia y TecnologĂ­a de Alimentos CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Instituto de Ciencia y TecnologĂ­a de Alimentos CĂłrdoba; ArgentinaFil: Bastida, Jaume. Universidad de Barcelona; EspañaFil: Cavallaro, Valeria. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de QuĂ­mica del Sur. Universidad Nacional del Sur. Departamento de QuĂ­mica. Instituto de QuĂ­mica del Sur; ArgentinaFil: Murray, Ana Paula. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - BahĂ­a Blanca. Instituto de QuĂ­mica del Sur. Universidad Nacional del Sur. Departamento de QuĂ­mica. Instituto de QuĂ­mica del Sur; ArgentinaFil: Puiatti, Marcelo. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba; ArgentinaFil: Oberti, Juan Carlos MarĂ­a. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂ­a Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Instituto Multidisciplinario de BiologĂ­a Vegetal; ArgentinaFil: Leiva GonzĂĄlez, Segundo. Universidad Privada Atenor Orrego. Museo de Historia Natural; PerĂșFil: Nicotra, Viviana Estela. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto Multidisciplinario de BiologĂ­a Vegetal. Universidad Nacional de CĂłrdoba. Facultad de Ciencias Exactas FĂ­sicas y Naturales. Instituto Multidisciplinario de BiologĂ­a Vegetal; ArgentinaFil: GarcĂ­a, Manuela Emila. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Centro CientĂ­fico TecnolĂłgico Conicet - CĂłrdoba. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Instituto de Investigaciones en FĂ­sico-quĂ­mica de CĂłrdoba; Argentin

    Use, tolerability, benefits and side effects of orthotic devices in Charcot-Marie-Tooth disease

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    Background: Shoe inserts, orthopaedic shoes, ankle-foot orthoses (AFOs) are important devices in Charcot-Marie-Tooth disease (CMT) management, but data about use, benefits and tolerance are scanty. Methods: We administered to Italian CMT Registry patients an online ad hoc questionnaire investigating use, complications and perceived benefit/tolerability/emotional distress of shoe inserts, orthopaedic shoes, AFOs and other orthoses/aids. Patients were also asked to fill in the Quebec User Evaluation of Satisfaction with assistive Technology questionnaire, rating satisfaction with currently used AFO and related services. Results: We analysed answers from 266 CMT patients. Seventy per cent of subjects were prescribed lower limb orthoses, but 19% did not used them. Overall, 39% of subjects wore shoe inserts, 18% orthopaedic shoes and 23% AFOs. Frequency of abandonment was high: 24% for shoe inserts, 28% for orthopaedic shoes and 31% for AFOs. Complications were reported by 59% of patients and were more frequently related to AFOs (69%). AFO users experienced greater emotional distress and reduced tolerability as compared with shoe inserts (p<0.001) and orthopaedic shoes (p=0.003 and p=0.045, respectively). Disease severity, degree of foot weakness, customisation and timing for customisation were determinant factors in AFOs' tolerability. Quality of professional and follow-up services were perceived issues. Conclusions: The majority of CMT patients is prescribed shoe inserts, orthopaedic shoes and/or AFOs. Although perceived benefits and tolerability are rather good, there is a high rate of complications, potentially inappropriate prescriptions and considerable emotional distress, which reduce the use of AFOs. A rational, patient-oriented and multidisciplinary approach to orthoses prescription must be encouraged

    Notulae to the Italian native vascular flora: 10

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    In this contribution, new data concerning the distribution of native vascular flora in Italy are presented. It includes new records, confirmations, exclusions, and status changes to the Italian administrative regions for taxa in the genera Artemisia, Chaetonychia, Cirsium, Cynanchum, Genista, Hieracium, Iberis, Melica, Misopates, Myosotis, Thalictrum, Trifolium, Utricularia, Veronica, and Vicia. Nomenclatural and distribution updates, published elsewhere, and corrigenda are provided as supplementary material

    Upper limb function in Duchenne muscular dystrophy: 24 month longitudinal data

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    The aim of the study was to establish 24 month changes in upper limb function using a revised version of the performance of upper limb test (PUL 2.0) in a large cohort of ambulant and non-ambulant boys with Duchenne muscular dystrophy and to identify possible trajectories of progression. Of the 187 patients studied, 87 were ambulant (age range: 7\u201315.8 years), and 90 non-ambulant (age range: 9.08\u201324.78). The total scores changed significantly over time (p<0.001). Non-ambulant patients had lower total scores at baseline (mean 19.7) when compared to the ambulant ones (mean 38.4). They also had also a bigger decrease in total scores over 24 months compared to the ambulant boys (4.36 vs 2.07 points). Multivariate model analysis showed that the Performance of Upper Limb changes reflected the entry level and ambulation status, that were independently associated to the slope of Performance of Upper Limb changes. This information will be of help both in clinical practice and at the time of designing clinical trials

    Dissipation of Knowledge and the Boundaries of the Multinational Enterprise

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    Detecting Starting Point Bias in Dichotomous-Choice Contingent Valuation Surveys

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