209 research outputs found

    Plectranthus zeylanicus: A rich source of secondary metabolites with antimicrobial, disinfectant and anti-inflammatory activities

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    Plectranthus zeylanicus Benth is used in Sri Lankan folk medicine as a remedy for inflammatory conditions and microbial infections. Our previous investigations revealed potent 5-lipoxygenase (5-LO) inhibitory activity in lipophilic extracts of this plant, supporting its anti-inflammatory potential. In-depth studies on the antimicrobial activity have not been conducted and the bioactive ingredients remained elusive. As a continuation of our previous work, the present investigation was undertaken to evaluate the antimicrobial activity of different extracts of P. zeylanicus and to isolate and characterize bioactive secondary metabolites. Different organic extracts of this plant were analyzed for their antibacterial activity, and the most active extract, i.e., dichloromethane extract, was subjected to bioactivity-guided fractionation, which led to the isolation of 7α-acetoxy-6β-hydroxyroyleanone. This compound displayed strong antibacterial activity against methicillin-resistant Staphylococcus aureus with a minimum inhibitory concentration of 62.5 µg/mL, and its disinfectant capacity was comparable to the potency of a commercial disinfectant. Moreover, 7α-acetoxy-6β-hydroxyroyleanone inhibits 5-LO with IC50 values of 1.3 and 5.1 µg/mL in cell-free and cell-based assays, respectively. These findings rationalize the ethnopharmacological use of P. zeylanicus as antimicrobial and anti-inflammatory remedy

    The Role of Anti- Cathapsin G among Patients with Rheumatiod Arthritis

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    Background: Perinuclear Antineutrophil Cytoplasmic Autoantibodies (pANCA) have been found in patients with rheumatiod arthritis. Cathepsin G was the major target antigen.The present study was to investigate the unknown target antigen of ANCA (Cathapsin G ) in patients with rheumatiod arthritis Objective: This study is to investigate the prevalence of anti-Cathapsin G and rheumatoid factor in Iraqi patients with rheumatiod arthritis. Patienties&Methods: From1st January until 30 June of 2011 fourty five rheumatiod arthritis patients referred to the immunological department in the teaching laboratory of medical city and twenty five apparently healthy individual used as a control group were investeged to rheumatic factor IgG, IgM ,IgA isotypes and anti-Cathapsin G were measured by using enzyme immunoassay technique. Result: This study showed that the age of patients with rheumatiod arthritis ranged between eigthen years and sixty six years with mean age of (36.08) , while the mean level for RF screen, RF IgG, RF IgM, RF IgA isotypes and anti-Cathapsin G were (160.71, 91.7, 136.64, 95.03 and > 9.2 ) respectively. There were 17(37.8%) males and 28(62.2%) females of RA patients. Immunologically, this study revealed that the serum RF screen was found more than 25 U/ml in all rheumatiod arthritis patients (100%, P: 0.0001 HS). On the other hand RF isotypes IgG ,RF IgM and IgA level were elevated more than 20 U/ml and it was detected in 31 (68.9%, P: 0.0001 HS), 31 (68.9%, P : 0.0001 HS) ,and 32 (71.1%, P: 0.0001 HS) patients respectively, while the rheumatiod factors (IgG,IgM, and IgA)were normal in healthy control group . Statistically RF screen has a highly significant association with RF IgG, IgM, and IgA (P= 0.0001). Anti-Cathapsin G was found in 12(26.7%, P value: 0.019) of patients with rheumatic arthritis patients. This study showed a association between the positive result of anti-Cathapsin G with RF IgG and RF IgM (35.5%, P: 0.047) the results were the same for both, while no association found with RF IgA (25%, P: 0.692). Conclusion: A significant correlation was found between anti-Cathapsin G and patients with rheumatiod arthritis and has a significant association with RF IgG and RF IgM while RF IgA had no relation with anti-Cathapsin G

    Arachidonic acid actions on functional integrity and attenuation of the negative effects of palmitic acid in a clonal pancreatic β-cell line

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    Chronic exposure of pancreatic β-cells to saturated non-esterified fatty acids can lead to inhibition of insulin secretion and apoptosis. Several previous studies have demonstrated that saturated fatty acids such as PA (palmitic acid) are detrimental to β-cell function compared with unsaturated fatty acids. In the present study, we describe the effect of the polyunsaturated AA (arachidonic acid) on the function of the clonal pancreatic β-cell line BRIN-BD11 and demonstrate AA-dependent attenuation of PA effects. When added to β-cell incubations at 100 μM, AA can stimulate cell proliferation and chronic (24 h) basal insulin secretion. Microarray analysis and/or real-time PCR indicated significant AA-dependent up-regulation of genes involved in proliferation and fatty acid metabolism [e.g. Angptl (angiopoietin-like protein 4), Ech1 (peroxisomal Δ3,5,Δ2,4-dienoyl-CoA isomerase), Cox-1 (cyclo-oxygenase-1) and Cox-2, P<0.05]. Experiments using specific COX and LOX (lipoxygenase) inhibitors demonstrated the importance of COX-1 activity for acute (20 min) stimulation of insulin secretion, suggesting that AA metabolites may be responsible for the insulinotropic effects. Moreover, concomitant incubation of AA with PA dose-dependently attenuated the detrimental effects of the saturated fatty acid, so reducing apoptosis and decreasing parameters of oxidative stress [ROS (reactive oxygen species) and NO levels] while improving the GSH/GSSG ratio. AA decreased the protein expression of iNOS (inducible NO synthase), the p65 subunit of NF-κB (nuclear factor κB) and the p47 subunit of NADPH oxidase in PA-treated cells. These findings indicate that AA has an important regulatory and protective β-cell action, which may be beneficial to function and survival in the ‘lipotoxic’ environment commonly associated with Type 2 diabetes mellitus

    Measurement of the cosmic ray spectrum above 4×10184{\times}10^{18} eV using inclined events detected with the Pierre Auger Observatory

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    A measurement of the cosmic-ray spectrum for energies exceeding 4×10184{\times}10^{18} eV is presented, which is based on the analysis of showers with zenith angles greater than 6060^{\circ} detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×10185.3{\times}10^{18} eV, the "ankle", the flux can be described by a power law EγE^{-\gamma} with index γ=2.70±0.02(stat)±0.1(sys)\gamma=2.70 \pm 0.02 \,\text{(stat)} \pm 0.1\,\text{(sys)} followed by a smooth suppression region. For the energy (EsE_\text{s}) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25(stat)1.2+1.0(sys))×1019E_\text{s}=(5.12\pm0.25\,\text{(stat)}^{+1.0}_{-1.2}\,\text{(sys)}){\times}10^{19} eV.Comment: Replaced with published version. Added journal reference and DO

    Energy Estimation of Cosmic Rays with the Engineering Radio Array of the Pierre Auger Observatory

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    The Auger Engineering Radio Array (AERA) is part of the Pierre Auger Observatory and is used to detect the radio emission of cosmic-ray air showers. These observations are compared to the data of the surface detector stations of the Observatory, which provide well-calibrated information on the cosmic-ray energies and arrival directions. The response of the radio stations in the 30 to 80 MHz regime has been thoroughly calibrated to enable the reconstruction of the incoming electric field. For the latter, the energy deposit per area is determined from the radio pulses at each observer position and is interpolated using a two-dimensional function that takes into account signal asymmetries due to interference between the geomagnetic and charge-excess emission components. The spatial integral over the signal distribution gives a direct measurement of the energy transferred from the primary cosmic ray into radio emission in the AERA frequency range. We measure 15.8 MeV of radiation energy for a 1 EeV air shower arriving perpendicularly to the geomagnetic field. This radiation energy -- corrected for geometrical effects -- is used as a cosmic-ray energy estimator. Performing an absolute energy calibration against the surface-detector information, we observe that this radio-energy estimator scales quadratically with the cosmic-ray energy as expected for coherent emission. We find an energy resolution of the radio reconstruction of 22% for the data set and 17% for a high-quality subset containing only events with at least five radio stations with signal.Comment: Replaced with published version. Added journal reference and DO

    Measurement of the Radiation Energy in the Radio Signal of Extensive Air Showers as a Universal Estimator of Cosmic-Ray Energy

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    We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8 \pm 0.7 (stat) \pm 6.7 (sys) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principle calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.Comment: Replaced with published version. Added journal reference and DOI. Supplemental material in the ancillary file

    Excessive Islet NO Generation in Type 2 Diabetic GK Rats Coincides with Abnormal Hormone Secretion and Is Counteracted by GLP-1

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    BACKGROUND: A distinctive feature of type 2 diabetes is inability of insulin-secreting beta-cells to properly respond to elevated glucose eventually leading to beta-cell failure. We have hypothesized that an abnormally increased NO production in the pancreatic islets might be an important factor in the pathogenesis of beta-cell dysfunction. PRINCIPAL FINDINGS: We show now that islets of type 2 spontaneous diabetes in GK rats display excessive NO generation associated with abnormal iNOS expression in insulin and glucagon cells, increased ncNOS activity, impaired glucose-stimulated insulin release, glucagon hypersecretion, and impaired glucose-induced glucagon suppression. Pharmacological blockade of islet NO production by the NOS inhibitor N(G)-nitro-L-arginine methyl ester (L-NAME) greatly improved hormone secretion from GK islets suggesting islet NOS activity being an important target to inactivate for amelioration of islet cell function. The incretin hormone GLP-1, which is used in clinical practice suppressed iNOS and ncNOS expression and activity with almost full restoration of insulin release and partial restoration of glucagon release. GLP-1 suppression of iNOS expression was reversed by PKA inhibition but unaffected by the proteasome inhibitor MG132. Injection of glucose plus GLP-1 in the diabetic rats showed that GLP-1 amplified the insulin response but induced a transient increase and then a poor depression of glucagon. CONCLUSION: The results suggest that abnormally increased NO production within islet cells is a significant player in the pathogenesis of type 2 diabetes being counteracted by GLP-1 through PKA-dependent, nonproteasomal mechanisms

    Consensus guidelines for the detection of immunogenic cell death

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    none82siApoptotic cells have long been considered as intrinsically tolerogenic or unable to elicit immune responses specific for dead cell-associated antigens. However, multiple stimuli can trigger a functionally peculiar type of apoptotic demise that does not go unnoticed by the adaptive arm of the immune system, which we named "immunogenic cell death" (ICD). ICD is preceded or accompanied by the emission of a series of immunostimulatory damage-associated molecular patterns (DAMPs) in a precise spatiotemporal configuration. Several anticancer agents that have been successfully employed in the clinic for decades, including various chemotherapeutics and radiotherapy, can elicit ICD. Moreover, defects in the components that underlie the capacity of the immune system to perceive cell death as immunogenic negatively influence disease outcome among cancer patients treated with ICD inducers. Thus, ICD has profound clinical and therapeutic implications. Unfortunately, the gold-standard approach to detect ICD relies on vaccination experiments involving immunocompetent murine models and syngeneic cancer cells, an approach that is incompatible with large screening campaigns. Here, we outline strategies conceived to detect surrogate markers of ICD in vitro and to screen large chemical libraries for putative ICD inducers, based on a high-content, high-throughput platform that we recently developed. Such a platform allows for the detection of multiple DAMPs, like cell surface-exposed calreticulin, extracellular ATP and high mobility group box 1 (HMGB1), and/or the processes that underlie their emission, such as endoplasmic reticulum stress, autophagy and necrotic plasma membrane permeabilization. We surmise that this technology will facilitate the development of next-generation anticancer regimens, which kill malignant cells and simultaneously convert them into a cancer-specific therapeutic vaccine.Kepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong-Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean-Ehrland; Riganti, Chiara; Rovere-Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei-Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, LorenzoKepp, Oliver; Senovilla, Laura; Vitale, Ilio; Vacchelli, Erika; Adjemian, Sandy; Agostinis, Patrizia; Apetoh, Lionel; Aranda, Fernando; Barnaba, Vincenzo; Bloy, Norma; Bracci, Laura; Breckpot, Karine; Brough, David; Buqué, Aitziber; Castro, Maria G; Cirone, Mara; Colombo, Maria I; Cremer, Isabelle; Demaria, Sandra; Dini, Luciana; Eliopoulos, Aristides G; Faggioni, Alberto; Formenti, Silvia C; Fučíková, Jitka; Gabriele, Lucia; Gaipl, Udo S; Galon, Jérôme; Garg, Abhishek; Ghiringhelli, François; Giese, Nathalia A; Guo, Zong Sheng; Hemminki, Akseli; Herrmann, Martin; Hodge, James W; Holdenrieder, Stefan; Honeychurch, Jamie; Hu, Hong Min; Huang, Xing; Illidge, Tim M; Kono, Koji; Korbelik, Mladen; Krysko, Dmitri V; Loi, Sherene; Lowenstein, Pedro R; Lugli, Enrico; Ma, Yuting; Madeo, Frank; Manfredi, Angelo A; Martins, Isabelle; Mavilio, Domenico; Menger, Laurie; Merendino, Nicolò; Michaud, Michael; Mignot, Gregoire; Mossman, Karen L; Multhoff, Gabriele; Oehler, Rudolf; Palombo, Fabio; Panaretakis, Theocharis; Pol, Jonathan; Proietti, Enrico; Ricci, Jean Ehrland; Riganti, Chiara; Rovere Querini, Patrizia; Rubartelli, Anna; Sistigu, Antonella; Smyth, Mark J; Sonnemann, Juergen; Spisek, Radek; Stagg, John; Sukkurwala, Abdul Qader; Tartour, Eric; Thorburn, Andrew; Thorne, Stephen H; Vandenabeele, Peter; Velotti, Francesca; Workenhe, Samuel T; Yang, Haining; Zong, Wei Xing; Zitvogel, Laurence; Kroemer, Guido; Galluzzi, Lorenz
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