ABSTRACT
Solidago chilensis Meyen (Asteraceae) is a medicinal and aromatic herb widely distributed in South America. From 2000 to the present numerous articles on this species have been published, mainly in the last decade where the pharmacological studies and articles on its secondary metabolites have risen sharply. S. chilensis has potential beneficial effects on human health, particularly as an anti- inflammatory because of its high flavonoid content. This work describes the research carried out on this species with emphasis on biological and phytochemical studies.
Solidago chilensis Meyen (Asteraceae) es una hierba aromaÌtica y medicinal, ampliamente difundida en SudameÌrica. A partir del anÌo 2000 se publicaron numerosos estudios sobre esta planta, particularmente en la uÌltima deÌcada donde se incrementoÌ sensiblemente el estudio de sus propiedades farmacoloÌgicas y de la quiÌmica de sus metabolitos secundarios. Es una planta con propiedades potencialmente beneficiosas para la salud humana, destacaÌndose particularmente por su actividad antiinflamatoria que puede ser atribuida al elevado contenido en flavonoides. En este trabajo revisamos exhaustivamente los antecedentes de esta planta desde un enfoque cronoloÌgico, con eÌnfasis en los estudios bioloÌgicos y fitoquiÌmicos.
Subject(s)
Plants, Medicinal/chemistry , Solidago/chemistry , Medicine, Traditional , Anti-Inflammatory Agents/chemistry , Antioxidants/chemistry , Quercetin/analysis , South America , AsteraceaeABSTRACT
OBJECTIVE: To investigate electrophysiologically the reproducibility of oropharyngeal swallowing in patients with ALS. METHODS: We enrolled 26 ALS patients, both with and without clinical signs of dysphagia, and 30 age-matched controls. The reproducibility of the electrophysiological signals related to the oral phase (electromyographic activity of the submental/suprahyoid muscles) and the pharyngeal phase (laryngeal-pharyngeal mechanogram) of swallowing across repeated swallows was assessed. To do this we computed two similarity indexes (SI) by using previously described mathematical algorithms. RESULTS: The reproducibility of oropharyngeal swallowing was significantly reduced both in patients with and in those without clinical signs of dysphagia, with more marked alterations being detected in the dysphagic group. The SI of both phases of swallowing, oral and pharyngeal, correlated significantly with dysphagia severity and disease severity. CONCLUSIONS: In ALS different pathophysiological mechanisms can alter the stereotyped motor behaviors underlying normal swallowing, thus reducing the reproducibility of the swallowing act. A decrease in swallowing reproducibility could be a preclinical sign of dysphagia and, beyond a certain threshold, a pathological hallmark of oropharyngeal dysphagia. SIGNIFICANCE: Electrophysiological assessment is a simple and useful tool for the early detection of swallowing abnormalities, and for the management of overt dysphagia in ALS.
Subject(s)
Amyotrophic Lateral Sclerosis/diagnosis , Deglutition Disorders/diagnosis , Deglutition , Electromyography/methods , Adult , Aged , Amyotrophic Lateral Sclerosis/complications , Amyotrophic Lateral Sclerosis/physiopathology , Case-Control Studies , Deglutition Disorders/etiology , Deglutition Disorders/physiopathology , Female , Humans , Male , Middle Aged , Pharynx/physiopathology , Reproducibility of ResultsABSTRACT
BACKGROUND: Nocturnal stridor and respiratory abnormalities are important features of multiple system atrophy (MSA) with relevance to patient survival, and they are detected and evaluated mainly through video-polysomnography (video-PSG). Diurnal laryngoscopy seems to yield abnormal findings only in the presence of significant vocal cord (VC) dysfunction. AIM: To assess whether specific electrophysiological patterns of diurnal EMG of VC muscles may indicate nocturnal stridor or respiratory dysfunctions in MSA patients. MATERIALS AND METHODS: Seventeen patients with probable MSA were examined. A full-night video-PSG to collect standard breathing parameters (apnea/hypopnea index, mean HbSAO2, oxygen desaturation index, total sleep time with HbSaO2 below 90%) was performed in all the patients. Laryngoscopy and EMG investigation of adductor (thyroarytenoid-TA) and abductor (posterior cricoarytenoid-PCA) muscles of the VCs were also performed. RESULTS: Both the laryngeal EMG abnormalities (based on MUAP analysis and kinesiologic EMG investigation of VC muscles) and the laryngoscopic alterations correlated with video-PSG respiratory abnormalities. Specific patterns of EMG findings were consistently found in MSA subjects with nocturnal stridor detected at PSG. In particular, the following EMG findings were related to the severity of breathing abnormalities and the presence of stridor on video-PSG: neurogenic pattern on MUAP analysis of the PCA, paradoxical activation of the TA during inspiration and tonic EMG activity of the TA during quiet breathing. CONCLUSIONS: Electromyographic/kinesiologic investigation of VC muscles during wakefulness provides additional information on the pathophysiology of the respiratory abnormalities in MSA patients that could be useful for guiding the choice of the best appropriate treatment and care.
Subject(s)
Circadian Rhythm/physiology , Laryngeal Muscles/physiopathology , Multiple System Atrophy/complications , Respiratory Sounds/physiopathology , Sleep Apnea Syndromes/etiology , Wakefulness/physiology , Aged , Electromyography , Female , Humans , Male , Middle Aged , Polysomnography , Severity of Illness IndexABSTRACT
alpha-Latrotoxin, a polypeptide neurotoxin known to cause massive release of transmitter from vertebrate nerve terminals, is thought to act by forming cation-selective channels in plasma membranes. This paper describes the steady-state current carried by Ca2+, Sr2+ and Ba2+ through pores of alpha-LaTx molecules incorporated in artificial bilayer membranes made of neutral lipids. Even when the solutions separated by the membrane are identical, the I-V relations rectify strongly, the current being higher when the side to which the toxin is added is positive. The polarity of the rectification is consistent with the hypothesis that the mechanism of action of the toxin is, at least in part, that of promoting inwardly directed flow of cations, and thus, accumulation of Ca2+ and other ions in the intracellular spaces. The dependence of the I-V characteristics on voltage and Ca2+ concentration is well described by a one-site, one-ion model for a channel. Three parameters of the model are deduced: the binding constant of the site for Ca2+, K = 1.5 M-1 (or K = 7 M-1 when activities are used instead of concentrations); the "electrical" distance of the site from the toxin-containing solution, alpha = 0.3; the free energy difference between the two barrier peaks, delta F = 0.26 kT. The values of the parameters deduced by studying the channel in the presence of Ca2+ give theoretical curves that also fit the data with Sr2+ and Ba2+, indicating a low level of discrimination among these three cations.
