3,307 research outputs found

    Norbornene Probes for the Detection of Cysteine Sulfenic Acid in Cells.

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    Norbornene derivatives were validated as probes for cysteine sulfenic acid on proteins and in live cells. Trapping sulfenic acids with norbornene probes is highly selective and revealed a different reactivity profile than the traditional dimedone reagent. The norbornene probe also revealed a superior chemoselectivity when compared to a commonly used dimedone probe. Together, these results advance the study of cysteine oxidation in biological systems

    Unlocking the in vitroanti- inflammatory and antidiabetic potential of Polygonum maritimum

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    Context: Several Polygonum species (Polygonaceae) are used in traditional medicine in Asia, Europe and Africa to treat inflammation and diabetes. Objective: Evaluate the in vitro antioxidant, anti-inflammatory and antidiabetic potential of methanol and dichloromethane extracts of leaves and roots of the halophyte Polygonum maritimum L. Material and methods: Antioxidant activity was determined (up to 1mg/mL) as radical-scavenging activity (RSA) of 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), copper (CCA) and iron (ICA) chelating activities and iron reducing power (FRAP). NO production was measured in lipopolysaccharide (LPS)-stimulated macrophages for 24 h at concentrations up to 100 mu g/mL and antidiabetic potential was assessed by alpha-amylase and alpha-glucosidase inhibition (up to 10 g/mL) assays. The phytochemical composition of the extracts was determined by gas chromatography-mass spectrometry (GC-MS). Results: The methanol leaf extract had the highest activity against DPPH center dot (IC50 = 26 mu g/mL) and ABTS1(+)center dot (IC50 = 140 mu g FRAP (IC50 = 48 mu g/mL) and CCA (IC50 = 770 mu g/mL). Only the dichloromethane leaf extract (LDCM) showed anti-inflammatory activity (IC50 = 48 mu g/mL). The methanol root (IC50 = 19 mu g/mL) and leaf (IC50 = 29 mu g/mL) extracts strongly inhibited baker's yeast alpha-glucosidase, but LDCM had higher rat's alpha-glucosidase inhibition (IC50 = 2527 mu g/mL) than acarbose (IC50 = 4638 mu g/mL). GC-MS analysis identified beta-sitosterol, stigmasterol, 1-octacosanol and linolenic acid as possible molecules responsible for the observed bioactivities. Conclusions: Our findings suggest P. maritimum as a source of high-value health promoting commodities for alleviating symptoms associated with oxidative and inflammatory diseases, including diabetes.XtremeBio project - Foundation for Science and Technology (FCT) [PTDC/MAR-EST/4346/2012]; Portuguese National Budget; FCT [CCMAR/Multi/04326/ 2013, IF/00049/2012, SFRH/BPD/86071/2012, UID/Multi/00612/2013

    Time periodicity and dynamical stability in two-boson systems

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    We calculate the period of recurrence of dynamical systems comprising two interacting bosons. A number of theoretical issues related to this problem are discussed, in particular, the conditions for small periodicity. The knowledge gathered in this way is then used to propose a notion of dynamical stability based on the stability of the period. Dynamical simulations show good agreement with the proposed scheme. We also apply the results to the phenomenon known as coherent population trapping and find stability conditions in this specific case.Comment: 7+ pages, 5 figure

    Clinical and echocardiographic features of aorto-atrial fistulas

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    Aorto-atrial fistulas (AAF) are rare but important pathophysiologic conditions of the aorta and have varied presentations such as acute pulmonary edema, chronic heart failure and incidental detection of the fistula. A variety of mechanisms such as aortic dissection, endocarditis with pseudoaneurysm formation, post surgical scenarios or trauma may precipitate the fistula formation. With increasing survival of patients, particularly following complex aortic reconstructive surgeries and redo valve surgeries, recognition of this complication, its clinical features and echocardiographic diagnosis is important. Since physical exam in this condition may be misleading, echocardiography serves as the cornerstone for diagnosis. The case below illustrates aorto-left atrial fistula formation following redo aortic valve surgery with slowly progressive symptoms of heart failure. A brief review of the existing literature of this entity is presented including emphasis on echocardiographic diagnosis and treatment

    Carvacrol, (-)-borneol and citral reduce convulsant activity in rodents

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    Carvacrol, a monoterpenic phenol present in essential oils of the Labiatae family, has been used through the ages as a source of flavor in food and for medicinal purposes. Borneol is a monoterpene found in several species of Artemisia and Dipterocarpaceae, used for anxiety, pain and anesthesia in traditional Chinese. Citral, a mixture of two geometrical isomers (neral and geranial), is one of the most important compounds in some citrus oils and has central nervous system (CNS) properties. The anticonvulsant effect of carvacrol (CARV), (-)-borneol (BOR) and citral (CIT) was investigated in two animal models of epilepsy. Mice were pretreated with CARV, BOR or CIT (50, 100, and 200 mg/kg, i.p.) 30 min before pentylenetetrazole (PTZ) or maximal electroshock (MES) tests, the two most important animal epilepsy tests. The latency for development of convulsions and protection percentage was recorded. In order to investigate the involvement of GABAergic system, flumazenil was utilized. These monoterpenes, CARV in a higher, but not in a lower dose (p < 0.001), BOR and CIT in all doses (p < 0.05 or p < 0.001), were capable of promoting an increase of latency for the development of convulsions induced by PTZ. Additionally, these compounds were efficient in preventing the tonic convulsions (p < 0.05) induced by MES. However, the GABAergic neurotransmitter system might be involved, at least in BOR effects. Henceforth, our results suggest that CARV, BOR and CIT possess anticonvulsant activity effect against PTZ-induced convulsions and MES.Key words: Carvacrol, (-)-borneol, citral, anticonvulsant activit

    SEPTIC SHOCK IN PATIENT WITH DISSEMINATED HISTOPLASMOSIS ASSOCIATED WITH AIDS: A CASE REPORT

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    SUMMARY Histoplasmosis is a systemic mycosis caused by Histoplasma capsulatum, which may present itself as a serious infection in immunocompromised individuals. We present a case of 31-year-old female with newly diagnosed HIV infection and history of fever, general and respiratory symptoms and diffuse hyperchromic papules through the body. She was admitted, with rapid progression to septic shock, and the presence of neutrophils filled with yeast-like organisms was detected on peripheral blood smear hematoscopia on the third day of hospitalization. The following is a brief review on the clinical picture and management of histoplasmosis
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