78 research outputs found

    An Academic Service Learning (AS-L) Activity within an Undergraduate Course in Pharmacology

    Get PDF
    Academic service learning (AS-L) is a type of active learning in which a student demonstrates knowledge and understanding through service to the community and reflection. The present report describes an activity in which AS-L was implemented as part of an undergraduate pharmacology course. The course is common to the curricula of the Doctor of Pharmacy, Physician Assistant and Toxicology programs at St. John’s University. In the AS-L project, students were charged to develop a presentation which they would then give to members of the community who were unfamiliar with the presentation topics. Students worked in teams and formed their presentations around discussion topics such as drugs versus natural substances, the medical benefits of drugs, the possible toxicities of drugs both legal and illegal, or the mechanisms by which drugs enter or leave our bodies. The student teams then traveled to various service sites throughout the greater university community with the goal of community outreach through education. In the present report, strengths and limitations of the AS-L project have been noted. The major strength of the project, as indicated from student reflection papers, was that each student in the team became an active learner and the otherwise “passive learning” environment of the classroom became an active one at the service site. All students in the team presented and answered questions. A major limitation of the activity was finding a suitable instrument for the assessment of student learning. Future AS-L courses of this type are anticipated to include pre and post surveys

    Potential Tumor Biomarkers for Ovarian Cancer

    Get PDF

    Evaluacija citotoksičnosti resveratrola i piceatanola u makrofazima, T-stanicama i stanicama kože

    Get PDF
    The cytotoxicity of resveratrol and of piceatannol, a structural analog of resveratrol, was examined in cultured cells. Using a MTT-based assay, which measures the conversion of 3-[4,5-dimethylthiazol-2- yl]-2,5-diphenyl tetrazolium bromide (MTT) to a colored formazan product in living cells, resveratrol was found to inhibit the viability of transformed mouse macrophages, tumor-derived human T cells and human epidermoid carcinoma cells in a concentration-dependent manner, with the effect decreasing in the order: T cells (LC50 ~27 µmol L-1, 24 h; ~9 µmol L-1; 48h) > macrophages (LC50 ~29 µmol L-1, 24 h; 39 µmol L-1, 48 h) > skin cells (LC50 ~91 µmol L-1, 24 h ; ~66 µmol L-1, 48 h). Paradoxically, a high concentration of resveratrol (50 µmol L-1) inhibited the proliferation of all three cell types, and a low concentration (5 µmol L-1) stimulated the proliferation of macrophages. The viability of macrophages was also decreased by piceatannol in a concentration-dependent manner. The stimulation of macrophages with zymosan lowered the cytotoxicity of both resveratrol and piceatannol. Scanning electron microscopy of cells treated with resveratrol revealed changes in cellular morphology that were consistent with toxicity. In macrophages and skin cells, resveratrol (50 µmol L-1) induced a time-dependent increase in reduced glutathione levels but did not alter the background levels of thiobarbituric acid-reactive substances. Taken together, the present data indicate that resveratrol is toxic to cultured macrophages, T cells and skin cells at concentrations ≥25 µmol L-1, and that the cytotoxicity occurs via a mechanism that does not involve oxidative stress. Furthermore, the degree of toxicity of both resveratrol and piceatannol towards macrophages depends on the activation status of these cells, with zymosan-activated cells appearing more resistant than nonstimulated cells.Citotoksičnost resveratrola i piceatanola, strukturnog analoga resveratrola, ispitivana je u uzgojenim stanicama. Primjenom MTT-testa koji mjeri pretvorbu 3-[4,5-dimetiltiazol-2-il]2,5-difenil-tetrazolijeva bromida (MTT) u obojeni formazan produkt u živim stanicama, na|eno je da resveratrol inhibira preživljavanje transformiranih makrofaga miša, ljudskih tumorskih T-stanica i humanih stanica epidermoidnog karcinoma u ovisnosti o koncentraciji, a učinak opada redom: T-stanice (LC50 ~27 µmol L-1, 24 h; ~9 µmol L-1; 48 h) > makrofazi (LC50 ~29 µmol L-1, 24 h; 39 µmol L-1, 48 h) >stanice kože (LC50 ~91 µmol L-1, 24 h; ~66 µmol L-1, 48 h). Paradoksalno, pri visokoj koncentraciji resveratrola (50 µmol L-1) inhibirana je proliferacija svih triju tipova stanica, a pri niskim koncentracijma (5 µmol L-1) stimulirana je proliferacija makrofaga. Preživljavanje makrofaga bilo je tako|er smanjeno primjenom piceatanola ovisno o koncentraciji. Stimulacija makrofaga zimosanom smanjila je citotoksičnost i resveratrola i piceatanola. Skenirajuća elektronska mikroskopija stanica tretiranih resveratrolom pokazala je promjene u morfologiji stanica, što je bilo u skladu s toksičnosti. U makrofazima i stanicama kože resveratrol (50 µmol L-1) inducirao je porast smanjenja razina glutationa ovisan o vremenu, ali nije mijenjao osnovne razine reaktivnih spojeva tiobarbiturne kiseline. Gledajući skupno, prikazani rezultati indiciraju da je resveratrol toksičan za uzgojene makrofage, T-stanice i stanice kože pri koncentracijama ≥25 µmol L-1 i da se citotoksičnost zbiva mehanizmom koji ne uključuje oksidativni stres. Nadalje, stupanj toksičnosti resveratrola i piceatanola prema makrofagima ovisi o aktivacijskom statusu tih stanica, pri čemu su stanice aktivirane zimosanom rezistentnije od nestimuliranih stanica

    Analozi epselena smanjuju toksičnost 2-kloroetil etilnog sulfida u A-431-stanicama

    Get PDF
    Vesicants are potent blistering agents. The prototype vesicant is sulphur mustard gas, first used in World War I, which still has no effective antidote. We used a mustard gas surrogate 2-chloroethyl ethyl sulphide (CEES) to study the ability of resveratrol (RES) and pterostilbene (PTS), two well-established stilbene antioxidants, ebselen (EB-1), an organoselenium compound, and three EB-1 analogues (EB-2, EB-3, and EB-4) to reduce CEES toxicity in human epidermoid carcinoma cells (A-431). Following a 24-hour incubation of a toxic concentration of CEES (1000 μmol L-1), we used the MTT [3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide] test to analyse cell viability. Different concentrations of test antioxidants alone (15 μmol L-1, 30 μmol L-1 or 60 μmol L-1) did not decrease cell viability. Treatment with CEES and test antioxidants for 24 h showed that only EB-1 and its analogues EB-2, EB-3, and EB-4 but not the stilbene compounds could rescue the cells from death. EB-1 and EB-4 were the most effective at reducing CEES cytotoxicity and did so in a concentration-dependent manner, while EB-2 and EB-3 demonstrated the least protective effect. In summary, the data described herein indicate that organoselenium antioxidants, especially EB-4, may prove useful as countermeasures to blistering agents.Plikavci izazivaju izražene mjehuriće na koži. Najpoznatiji je svakako sumporni iperit, koji se prvi put uporabio u 1. svjetskom ratu i do današnjega dana nema djelotvornog protuotrova. U ispitivanju smo rabili zamjenu za iperit, 2-kloroetil etilni sulfi d (CEES) da bismo testirali sposobnost resveratrola (RES) i pterostilbena (PTS), dvaju poznatih stilbenskih antioksidansa, organoselenijeva spoja epselena (EB-1) te njegovih triju analoga (EB-2, EB-3 i EB-4) da smanji toksičnost CEES-a u humanih stanica epidermoidnog karcinoma (A-431). Vijabilnost stanica testirali smo s pomoću 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazol bromida (MTT) nakon 24-satne inkubacije s toksičnom koncentracijom CEES-a (1000 μmol L-1). Antioksidansi davani sami u različitim koncentracijama (15 μmol L-1, 30 μmol L-1, odnosno 60 μmol L-1) nisu smanjili vijabilnost stanica. Dvadesetčetverosatna primjena CEES-a i testiranih antioksidansa pokazala je da samo EB-1 i njegovi analozi EB-2, EB-3 i EB-4 mogu spriječiti smrt stanica, ali ne i stilbenski spojevi. EB-1 i EB-4 pokazali su se najdjelotvornijima u ublažavanju toksičnosti CEES-a u skladu s koncentracijom, dok su se EB-2 i EB-3 pokazali najmanje djelotvornima. Ovdje prikazani podaci upućuju na to da organoselenijevi antioksidansi, a napose EB-4, mogu biti korisni protuotrovi plikavcima

    Crosstalk between reactive oxygen species and pro-inflammatory markers in developing various chronic diseases: a review

    Get PDF
    The inflammation process in the human body plays a central role in the pathogenesis of many chronic diseases. In addition, reactive oxygen species (ROS) exert potentially a decisive role in human body, particularly in physiological and pathological process. The chronic inflammation state could generate several types of diseases such as cancer, atherosclerosis, diabetes mellitus and arthritis, especially if it is concomitant with high levels of pro-inflammatory markers and ROS. The respiratory burst of inflammatory cells during inflammation increases the production and accumulation of ROS. However, ROS regulate various types of kinases and transcription factors such nuclear factor-kappa B which is related to the activation of pro-inflammatory genes. The exact crosstalk between pro-inflammatory markers and ROS in terms of pathogenesis and development of serious diseases is still ambitious. Many studies have been attempting to determine the mechanistic mutual relationship between ROS and pro-inflammatory markers. Therefore hereby, we review the hypothetical relationship between ROS and pro-inflammatory markers in which they have been proposed to initiate cancer, atherosclerosis, diabetes mellitus and arthritis

    A naturally occurring allele of BRCA1 coding for a temperature-sensitive mutant protein

    No full text
    Recent evidence suggests that the breast and ovarian cancer susceptibility gene product BRCA1 is involved in at least two fundamental cellular processes: transcriptional regulation and DNA repair. However, the mechanism of action of BRCA1 in either of these processes is still unknown. Here, we report the characterization of a disease-predisposing allele of BRCA1, identified in a family with several cases of ovarian cancer, coding for a protein that displays temperature-sensitive activity in transcriptional activation. The mutant protein differs from the wild type protein at a single amino acid, R1 699W that occurs in a region at the N-terminal BRCT domain that is highly conserved among BRCA1 homologs. When the C-terminus of the mutant protein (aa 1560-1863) was fused to a heterologous GAL4 DNA-binding domain and expressed in yeast or mammalian cells, it was able to activate transcription of a reporter gene to levels observed for wild type BRCA1 at the permissive temperature (30degreesC) but exhibited significantly less transcription activity at the restrictive temperature (37degreesC or 39degreesC). Our results indicate that the transcriptional activity of the R1699W mutant can be modulated as a function of temperature and provide a novel experimental approach which can be utilized to dissect the molecular mechanism(s) of BRCA1 in processes related to transcription

    Assessment of the time-dependent dermatotoxicity of mechlorethamine using the mouse ear vesicant model

    No full text
    Mechlorethamine (HN2) is an alkylating agent and sulfur mustard gas mimetic which is also used in anticancer therapy. HN2 is associated with skin inflammation and blistering which can lead to secondary infections. The purpose of the present study was to investigate the time-dependent dermatotoxicity of HN2 using the mouse ear vesicant model (MEVM). To this end, our operational definition of dermatotoxicity included tissue responses to HN2 consistent with an increase in the wet weights of mouse ear punch biopsies, an increase in the morphometric thickness of H&E stained ear sections and histopathologic observations including tissue edema, inflammatory cell infiltration and vesication. The ears of male Swiss Webster mice were topically exposed to a single dose of HN2 (0.5 µmol/ear) or DMSO vehicle (5 µl/ear) or left untreated (naive). Mice were then euthanized at 15 min, 1, 2, 4, 8 or 24 hr following HN2 exposure. Compared to control ears, mouse ears exposed to HN2 at all time points showed an increase in wet weights, morphometric thickness, edema, inflammatory cell infiltration and signs of vesication. The incidence in tissue vesication sharply increased between 4 and 8 hr after exposure, revealing that tissue vesication is well established by 8 hr and remains elevated at 24 hr after exposure. It is noteworthy that, compared to control ears, mouse ears treated with DMSO vehicle alone also exhibited an increase in wet weights and morphometric thickness at 15 min, 1, 2 and 4 hr following treatment; however, these vehicle effects begin to subside after 4 hr. The results obtained here using the MEVM provide a more holistic understanding of the kinetics of vesication, and indicate that time points earlier than 24 hr may prove useful not only for investigating the complex mechanisms involved in vesication but also for assessing the effects of vesicant countermeasures
    corecore