88 research outputs found
Chemical composition of the essential oils from leaves and flowers of Passiflor sexocellata and Passiflora trifasciata
The chemical composition of the essential oils of Passiflora sexocellata and Passiflora trifasciata (Passifloraceae, subgenus Decaloba) were
studied for the first time. Essential oils were obtained by steam distillation of fresh leaves and flowers. The chemical composition
was assessed by using GC/FID and GC/MS. For P. sexocellata leaves, the optimized analytical procedure allowed the identification
of 33 compounds (75% of the total oil composition) and 29 (74% of the total oil composition) in flowers. Regarding P. trifasciata,
35 compounds (76% of the total oil composition) were detected in leaves and 32 (71% of the total oil composition) in flowers.
Terpenes and mono unsaturated hydrocarbons were quantified as major constituents of the volatile fraction in flowers (17.0 to
52.6%) and (13.7 to 20.0%). Organic acids were detected in both leaves and flowers with a percentage ranging from 3.3% to 32.0%.
Aldehydes were also detected in leaves (12.6 to 41.4%) and in flowers (1.4 to 5.1%). The GC/MS analyzes allowed alcohols to be
detected in leaves (20.6 to 42.9%) and in flowers (8.2 to 18.1%). These compounds represent the most important feature of the
large Passiflora family. Moreover, a critical role in the coevolved mechanisms of pollinators' interaction has been investigated
Microwave-Assisted and Conventional Extractions of Volatile Compounds from Rosa x damascena Mill. Fresh Petals for Cosmetic Applications
Rosa x damascena Mill. essential oil is mainly used in the cosmetics and perfumery industry, but it also finds application in the food industry as a flavoring agent. The chemical composition of essential oils is affected by environment, soil, harvesting technique, storage condition, and extraction methods. Nowadays, the study and design of greener, more efficient, and sustainable extractive procedures is the main and strategic focus in the chemical research and development of botanical derivatives, especially as regards fragrances and essential oils. Several technologies are available, and the best method to use depends on the desired chemicals, but conventional extractive processes are often laborious and time-consuming, involve large amounts of solvents, and may cause the partial loss of volatiles, affecting the quality of the final product. In the last decade, microwave irradiation has been successfully applied to classical techniques, often improving the general extractive efficiency and extract quality. In the present paper, as a preliminary analytical screening approach, two microwave-mediated techniques, Solvent-Free Microwave Extraction (SFME) and Microwave Hydrodiffusion and Gravity (MHG), and two conventional procedures, Hydrodistillation (HD) and Steam Distillation (SD), were applied and compared for the extraction of volatile compounds from R. x damascena fresh petals to highlight differences and advantages of the selected procedure and of the obtained extracts useful in a cosmetic context as fragrances or active ingredients. The chemical composition of the extracts was investigated by GC-MS and GC-FID. Sixty-one components, distributed in the four techniques, were identified. SD and HD are dominated by oxygenated terpenes (59.01% and 50.06%, respectively), while MHG and SFME extracts are dominated by alcohols (61.67% and 46.81%, respectively). A relevant variability in the composition of the extracts relating to the extraction techniques used was observed. To point out the correlation between the process and composition of the obtained natural products, principal component analysis (PCA) of the data extracted from GC-FID was used. Taking into account a cosmetic application, SFME shows several advantages when compared with the other procedures. The extract (obtained in a significantly higher amount) contains a meaningful lower level of potential fragrance allergenic compounds and quite a double amount of benzyl alcohol and 2-phenyl ethanol that can also enhance the preservative action in personal care products
Dual Effect of Beta-Amyloid on α7 and α4β2 Nicotinic Receptors Controlling the Release of Glutamate, Aspartate and GABA in Rat Hippocampus
BACKGROUND: We previously showed that beta-amyloid (Aβ), a peptide considered as relevant to Alzheimer's Disease, is able to act as a neuromodulator affecting neurotransmitter release in absence of evident sign of neurotoxicity in two different rat brain areas. In this paper we focused on the hippocampus, a brain area which is sensitive to Alzheimer's Disease pathology, evaluating the effect of Aβ (at different concentrations) on the neurotransmitter release stimulated by the activation of pre-synaptic cholinergic nicotinic receptors (nAChRs, α4β2 and α7 subtypes). Particularly, we focused on some neurotransmitters that are usually involved in learning and memory: glutamate, aspartate and GABA. METHODOLOGY/FINDINGS: WE USED A DUAL APPROACH: in vivo experiments (microdialysis technique on freely moving rats) in parallel to in vitro experiments (isolated nerve endings derived from rat hippocampus). Both in vivo and in vitro the administration of nicotine stimulated an overflow of aspartate, glutamate and GABA. This effect was greatly inhibited by the highest concentrations of Aβ considered (10 µM in vivo and 100 nM in vitro). In vivo administration of 100 nM Aβ (the lowest concentration considered) potentiated the GABA overflow evoked by nicotine. All these effects were specific for Aβ and for nicotinic secretory stimuli. The in vitro administration of either choline or 5-Iodo-A-85380 dihydrochloride (α7 and α4β2 nAChRs selective agonists, respectively) elicited the hippocampal release of aspartate, glutamate, and GABA. High Aβ concentrations (100 nM) inhibited the overflow of all three neurotransmitters evoked by both choline and 5-Iodo-A-85380 dihydrochloride. On the contrary, low Aβ concentrations (1 nM and 100 pM) selectively acted on α7 subtypes potentiating the choline-induced release of both aspartate and glutamate, but not the one of GABA. CONCLUSIONS/SIGNIFICANCE: The results reinforce the concept that Aβ has relevant neuromodulatory effects, which may span from facilitation to inhibition of stimulated release depending upon the concentration used
Magnetic resonance mammography in the evaluation of recurrence at the prior lumpectomy site after conservative surgery and radiotherapy
INTRODUCTION: The aim was to assess the value of magnetic resonance mammography (MRM) in the detection of recurrent breast cancer on the prior lumpectomy site in patients with previous conservative surgery and radiotherapy. METHODS: Between April 1999 and July 2003, 93 consecutive patients with breast cancer treated with conservative surgery and radiotherapy underwent MRM, when a malignant lesion on the site of lumpectomy was suspected by ultrasound and/or mammography. MRM scans were evaluated by morphological and dynamic characteristics. MRM diagnosis was compared with histology or with a 36-month imaging follow-up. Enhancing areas independent of the prior lumpectomy site, incidentally detected during the MRM, were also evaluated. RESULTS: MRM findings were compared with histology in 29 patients and with a 36-month follow-up in 64 patients. MRM showed 90% sensitivity, 91.6% specificity, 56.3% positive predictive value and 98.7% negative predictive value for detection of recurrence on the surgical scar. MRM detected 13 lesions remote from the scar. The overall sensitivity, specificity, positive predictive value and negative predictive value of MRM for detection of breast malignancy were 93.8%, 90%, 62.5% and 98.8%, respectively. CONCLUSION: MRM is a sensitive method to differentiate recurrence from post-treatment changes at the prior lumpectomy site after conservative surgery and radiation therapy. The high negative predictive value of this technique can avoid unnecessary biopsies or surgical treatments
Drug prescription in elderly hospitalized patients with cognitive impairment in the Italian Dementia Friendly Hospital Project
BackgroundOlder patients with cognitive impairment represent a significant proportion of the patients hospitalized for various acute illnesses. The health staff is not prepared to deal with such patients which do not fit the standard of care of the hospital stay. Accordingly, we recorded a series of clinical parameters reflecting the health status and the drug prescriptions at the entry and during hospital stay before and after a brief (5 hrs. frontal teaching) intervention of staff training, focusing on improving the management of patients with cognitive impairment.MethodsParticipants were evaluated within 48 h of admission and at discharge with Mini Mental State Examination (MMSE), Barthel Index, Instrumental Activity of Daily Life (IADL), and Hospital Anxiety and Depression Scale (HADS). A preliminary analysis of 68 hospitalized participants aged 65 and older with cognitive impairment (MMSE ≥ 16, ≤24) allocated in the control group (n = 34, 20 females, 82.38 years) and intervention group (n = 34, 20 females, 81.97 years) was performed. For each patient, the number of prescriptions, sedative and anticholinergic load, and drug–drug interactions were evaluated.ResultsParticipants presented a widespread polypharmacy receiving as average 6.9 (+/- 1.7 drugs/daily in the control group) and 5.9 (+/- 1.6 drugs/daily in the intervention group), the difference being not statistically significant (P = 0,068). Also, the sedative load presented a trend toward lower values in the intervention group. The results concerning the other clinical indices (submitted elsewhere) show that personnel training significantly improved the functional and anxiety parameters at discharge.ConclusionsThe results suggest that an intervention, focused on improving dementia care practices in health staff, having the potential to improve outcomes for hospitalized older adults with cognitive impairment, but not directly designed to manage drug polypharmacy, is not sufficient to modify drug prescription patterns
A f influences nicotinic-stimulated release of both excitatory and inhibitory neurotransmitters in rat hippocampus
- …