Combining excitation-emission matrix fluorescence spectroscopy, Parallel Factor Analysis, cyclodextrin-modified micellar electrokinetic chromatography and Partial Least Squares Class-Modelling for green tea characterization

In this study, an alternative analytical approach for analyzing and characterizing green tea (GT) samples is proposed, based on the combination of excitation–emission matrix (EEM) fluorescence spectroscopy and multivariate chemometric techniques. The three-dimensional spectra of 63 GT samples were recorded using a Perkin–Elmer LS55 luminescence spectrometer; emission spectra were recorded between 295 and 800 nm at excitation wavelength ranging from 200 to 290 nm, with excitation and emission slits both set at 10 nm. The excitation and emission profiles of two factors were obtained using Parallel Factor Analysis (PARAFAC) as a 3-way decomposition method. In this way, for the first time, the spectra of two main fluorophores in green teas have been found. Moreover, a cyclodextrin-modified micellar electrokinetic chromatography method was employed to quantify the most represented catechins and methylxanthines in a subset of 24 GT samples in order to obtain complementary information on the geographical origin of tea. The discrimination ability between the two types of tea has been shown by a Partial Least Squares Class-Modelling performed on the electrokinetic chromatography data, being the sensitivity and specificity of the class model built for the Japanese GT samples 98.70% and 98.68%, respectively. This comprehensive work demonstrates the capability of the combination of EEM fluorescence spectroscopy and PARAFAC model for characterizing, differentiating a...
Source: Journal of Pharmaceutical and Biomedical Analysis - Category: Drugs & Pharmacology Source Type: research

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DiscussionMCI prevalence varied among Hispanic/Latino backgrounds, but not as widely as reported in the previous studies. CVD risk and depressive symptoms were associated with increased MCI, whereas APOE4 was not, suggesting alternative etiologies for MCI among diverse Hispanics/Latinos. Our findings suggest that mitigating CVD risk factors may offer important pathways to understanding and reducing MCI and possibly dementia among diverse Hispanics/Latinos.
Source: Alzheimer's and Dementia: The Journal of the Alzheimer's Association - Category: Geriatrics Source Type: research
CONCLUSIONS: Local application of sevoflurane in the wound bed appears to exhibit analgesic, antimicrobial, and positive healing effects. It could be a promising alternative treatment to be included as a therapeutic option for wound care. PMID: 31730517 [PubMed - in process]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: Cutaneous vasculopathy related to the skin, such as livedo reticularis and ulcers of torpid evolution due to cutaneous vasculopathy are extremely rare. Thus, it is necessary to include skin ulcers as one of the phenotypic manifestations of NF-1. PMID: 31730516 [PubMed - in process]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: The authors suggest stasis mucinosis and OALM represent the spectrum of euthyroid mucin depositional disease in varying clinical settings. PMID: 31730515 [PubMed - in process]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: From this case report, the authors believe NPWTi-d may be more effective in cases with intractable ulcers associated with infection that need better granulation. PMID: 31730514 [PubMed - in process]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
Authors: Roshangar L, Soleimani Rad J, Kheirjou R, Reza Ranjkesh M, Ferdowsi Khosroshahi A Abstract Burn wounds are one of the main causes of skin damage. Based on World Health Organization statistics, almost 300 000 people worldwide die of burns each year. In severe burns, the cells and blood vessels are often injured and the blood supply to the wound is disturbed. Many factors such as oxygenation, infection, aging, hormones, and nutrition potentially can influence burn progression and disrupt repair with unbalanced release of various growth factors and cytokines. Different treatment approaches such as dressings a...
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: An illustrated guide for dressing application in burn wounds was developed and validated for content by an expert panel. PMID: 31730512 [PubMed - as supplied by publisher]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: This is the largest cohort reported in the literature of patients with frostbite injuries treated with HBOT. Hyperbaric oxygen therapy may show positive impact on the demarcation level of frostbite and, despite the common side effects, it generally causes no long-term sequelae. PMID: 31730511 [PubMed - as supplied by publisher]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: This is an easily reproducible and safe technique for effluent control in patients with Björk grade 4 abdomen with established EAF. PMID: 31730510 [PubMed - as supplied by publisher]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
CONCLUSIONS: These results suggest the importance of arterial-arterial connections such as the pedal arch to the healing potential of foot and ankle wounds after STSG in this high-risk patient population. PMID: 31730509 [PubMed - as supplied by publisher]
Source: Wounds - Category: General Medicine Tags: Wounds Source Type: research
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