Chemicals and Drugs Commons^™

Ideology Masquerading As Science: The Case Of Endocrine Disrupter Screening Programmes, Troy Seidle

Troy Seidle, PhD

The global move to develop novel testing methods and strategies to identify suspected endocrine disrupting chemicals offers a unique opportunity to move away from traditional animal testing paradigms in this new area of regulatory concern. Regrettably, the programmes under development, both in the USA and internationally through the OECD, have thus far failed to consider in vitro and other nonanimal test methods as more than “pre-screening” or “priority-setting” tools in a larger, animal-based testing strategy. Validation efforts to date have focused almost exclusively on the modification of existing animal tests to detect “endocrine effects”, with no demonstrable effort to promote …

Dual Engagement Of The Nlrp3 And Aim2 Inflammasomes By Plasmodium-Derived Hemozoin And Dna During Malaria, Parisa Kalantari, Rosane B. Deoliveira, Jennie Chan, Yolanda Corbett, Vijay A. K. Rathinam, Andrea Stutz, Eicke Latz, Ricardo T. Gazzinelli, Douglas T. Golenbock, Katherine A. Fitzgerald

Katherine A. Fitzgerald

Hemozoin (Hz) is the crystalline detoxification product of hemoglobin in Plasmodium-infected erythrocytes. We previously proposed that Hz can carry plasmodial DNA into a subcellular compartment that is accessible to Toll-like receptor 9 (TLR9), inducing an inflammatory signal. Hz also activates the NLRP3 inflammasome in primed cells. We found that Hz appears to colocalize with DNA in infected erythrocytes, even before RBC rupture or phagolysosomal digestion. Using synthetic Hz coated in vitro with plasmodial genomic DNA (gDNA) or CpG oligodeoxynucleotides, we observed that DNA-complexed Hz induced TLR9 translocation, providing a priming and an activation signal for inflammasomes. After phagocytosis, Hz and …

Synchronous Opening And Closing Motions Are Essential For Camp-Dependent Protein Kinase A Signaling, Atul K. Srivastava, Leanna R. Mcdonald, Alessandro Cembran, Jonggul Kim, Larry R. Masterson, Christopher L. Mcclendon, Susan S. Taylor, Gianluigi Veglia

Larry Masterson

Regulated Splicing Of The Alpha6 Integrin Cytoplasmic Domain Determines The Fate Of Breast Cancer Stem Cells, Hira Lal Goel, Tatiana Gritsko, Bryan Pursell, Cheng Chang, Leonard D. Shultz, Dale L. Greiner, Jens Henrik Norum, Rune Toftgard, Leslie M. Shaw, Arthur M. Mercurio

Arthur M. Mercurio

Although the alpha6beta1 integrin has been implicated in the function of breast and other cancer stem cells (CSCs), little is known about its regulation and relationship to mechanisms involved in the genesis of CSCs. We report that a CD44(high)/CD24(low) population, enriched for CSCs, is comprised of distinct epithelial and mesenchymal populations that differ in expression of the two alpha6 cytoplasmic domain splice variants: alpha6A and alpha6B. alpha6Bbeta1 expression defines the mesenchymal population and is necessary for CSC function, a function that cannot be executed by alpha6A integrins. The generation of alpha6Bbeta1 is tightly controlled and occurs as a consequence of …

Cancerous Contradictions: The Mis-Regulation Of Human Carcinogens Based On Animal Data, Andrew Knight, Jarrod Bailey, Jonathan Balcombe

Jonathan Balcombe, PhD

The regulation of human exposures to potential carcinogens constitutes society’s most important use of animal carcinogenicity data. However, for environmental contaminants of greatest U.S. concern, we found that in most cases (58.1%; 93/160) the U.S. Environmental Protection Agency (EPA) considered the animal data inadequate to support a classification of probable human carcinogen or noncarcinogen.

The World Health Organisation’s International Agency for Research on Cancer (IARC) is a leading international authority on carcinogenicity assessments. For chemicals lacking human exposure data (the great majority), IARC classifications of identical chemicals were significantly more conservative than EPA classifications (p

Effects Of Polychlorinated Biphenyl (Pcb) On Response Perseveration And Ultrasonic Vocalization Emission In Rat During Development, Howard Cromwell

Howard Casey Cromwell

The 3 major symptoms of autistic spectrum disorders include 1) social behavioral alterations, 2) problems in communication and 3) higher-order motoric deficits of perseveration and stereotyped movements. Previous work has shown that early developmental exposure to polychlorinated biphenyls (PCBs) alters rat pup social motivation and juvenile rat social recognition/investigation. The present work extends this previous research by examining how perinatal PCB exposure alters motoric functions and communication abilities at different stages of development. Action perseveration was examined using performance measures from a T-maze environment. Communication abilities were evaluated by monitoring ultrasound emission in rat pups during a brief isolation from …

Leica Microscope Gpu Deconvolution Stellaris Fish Dataset #1, George Mcnamara

George McNamara

McNamara 20131101Fri Leica widefield microscope CUDA Deconvolution Stellaris FISH probe cultured cells dataset #1.zip

A text file in the zip archive has experiment details. I am posting this online so that researchers - whether academic or commercial - can evaluate the acquired data, the Bruce and Butte 2013 Optics Express ( http://www.opticsinfobase.org/oe/fulltext.cfm?uri=oe-21-4-4766 ) deconvolution result (note: I may not have used optimal settings), and to compare these deconvolution results to other methods. If anyone generates alternative spatial deconvolution output, such as from: * SVI Huygens * Media Cy AutoQuant * Agard's ER-Decon (Arigovindan 2013 PNAS) * Vicidomini SGP GPU Deconv …

Identification Of A Human Monoclonal Antibody To Replace Equine Diphtheria Anti-Toxin For The Treatment Of Diphtheria, Leila M. Sevigny, Brian J. Booth, Kirk J. Rowley, Brett A. Leav, Peter S. Cheslock, Kerry A. Garrity, Susan Sloan, Gregory J. Babcock, William D. Thomas, Mark Klempner, Yang Wang

William D Thomas Jr

Diphtheria anti-toxin (DAT) has been used to treat Corynebacterium diphtheriae infection for over one hundred years. While the global incidence of diphtheria has declined in the 20th century, the disease remains endemic in many parts of the world and significant outbreaks still occur. Diphtheria anti-toxin is an equine polyclonal antibody with considerable side effects that is in critically short supply globally. A safer, more readily available alternative to DAT would be desirable. In the current study, we cloned human monoclonal antibodies (HuMabs) directly from antibody secreting cells of human volunteers immunized with Td vaccine. We isolated a diverse panel of …

Alcohol Facilitates Hcv Rna Replication Via Up-Regulation Of Mir-122 Expression And Inhibition Of Cyclin G1 In Human Hepatoma Cells, Wei Hou, Terence Bukong, Karen Kodys, Gyongyi Szabo

Gyongyi Szabo

BACKGROUND: Clinical studies demonstrate synergistic liver damage by alcohol and hepatitis C virus (HCV); however, the mechanisms by which alcohol promotes HCV infection remain obscure. The liver-specific microRNA-122 (miR-122) regulates HCV replication and expression of host genes, including Cyclin G1. Here, we hypothesized that alcohol regulates miR-122 expression and thereby modulates HCV RNA replication. METHODS: The J6/JFH/Huh-7.5 model of HCV infection was used in this study. Real-time quantitative polymerase chain reaction, Western blotting, electrophoretic mobility shift assay, and confocal microscopy were used for experimental analysis. RESULTS: We found that acute alcohol exposure (25 mM) significantly increased intracellular HCV RNA as …

Structural And Thermodynamic Basis Of Amprenavir/Darunavir And Atazanavir Resistance In Hiv-1 Protease With Mutations At Residue 50, Seema Mittal, Rajintha Bandaranayake, Nancy King, Moses Prabu-Jeyabalan, Madhavi Nalam, Ellen Nalivaika, Nese Yilmaz, Celia Schiffer

Celia A. Schiffer

Drug resistance occurs through a series of subtle changes that maintain substrate recognition but no longer permit inhibitor binding. In HIV-1 protease, mutations at I50 are associated with such subtle changes that confer differential resistance to specific inhibitors. Residue I50 is located at the protease flap tips, closing the active site upon ligand binding. Under selective drug pressure, I50V/L substitutions emerge in patients, compromising drug susceptibility and leading to treatment failure. The I50V substitution is often associated with amprenavir (APV) and darunavir (DRV) resistance, while the I50L substitution is observed in patients failing atazanavir (ATV) therapy. To explain how APV, …

A Thousand Tiny Pieces: The Federal Circuit’S Fractured Myriad Ruling, Lessons To Be Learned, And The Way Forward, Jonathan R. K. Stroud

Jonathan R. K. Stroud

No abstract provided.

Modeling Colorectal Cancer As A 3-Dimensional Disease In A Dish: The Case For Drug Screening Using Organoids, Zebrafish, And Fruit Flies, Michele Markstein

Michele Markstein

This review discusses recent shifts in the understanding of colorectal cancer as a stem cell based disease, based on findings that tie patient prognosis to the presence of cancer stem cells in colorectal tumors. Currently no drugs specifically target CSCs in colorectal tumors. However, recent advances in the culturing of colorectal stem cells using mammalian organoids, zebrafish, and Drosophila offer promising avenues for anti-CSC drug discovery.

Structure And Dynamics Of A Primordial Catalytic Fold Generated By In Vitro Evolution, Fa-An Chao, Aleardo Morelli, John C. Haugner Iii, Lewis Churchfield, Lei Shi, Larry R. Masterson, Ritimukta Sarangi, Gianluigi Veglia, Burckhard Seelig

Larry Masterson

Lack Of Association Between Gly82ser, 1704g/T And 2184a/G Of Rage Gene Polymorphisms And Retinopathy Susceptibility In Malaysian Diabetic Patients, Rozaida @ Poh Yuen Ying

Rozaida @ Poh Yuen Ying

Diabetic retinopathy is the most common diabetic eye disease, occurring in about 60% of type 2 diabetic patients. Other than known clinical risk factors, the influence of genes has been suggested as part of the development of diabetic retinopathy. We investigated the association of Gly82Ser, 1704G/T and 2184A/G polymorphisms in the RAGE gene with retinopathy in type 2 diabetic patients in Malaysia. Ninety-eight unrelated retinopathy patients and 185 unrelated healthy controls from all over Malaysia were recruited in this study. The allele and genotype frequencies of the three gene polymorphisms were investigated using PCR-RFLP. The allele frequency of the three …

Igf2bp2 Alternative Variants Associated With Glutamic Acid Decarboxylase Antibodies Negative Diabetes In Malaysian Subjects, Rozaida @ Poh Yuen Ying

Rozaida @ Poh Yuen Ying

Background: The association of Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) common variants (rs4402960 and rs1470579) with type 2 diabetes (T2D) has been performed in different populations. The aim of this study was to evaluate the association of alternative variants of IGF2BP2; rs6777038, rs16860234 and rs7651090 with glutamic acid decarboxylase antibodies (GADA) negative diabetes in Malaysian Subjects. Methods/Principal Findings: IGF2BP2; rs6777038, rs16860234 and rs7651090 single nucleotide polymorphisms (SNPs) were genotyped in 1107 GADA negative diabetic patients and 620 control subjects of Asian from Malaysia. The additive genetic model adjusted for age, race, gender and BMI showed that alternative variants; …

Paraoxonase 1 Status In Keratoconus: A Preliminary Study Of Activity And Polymorphism, Rozaida @ Poh Yuen Ying

Rozaida @ Poh Yuen Ying

OBJECTIVE: To determine the activity of paraoxonase 1 (PON1) in keratoconus in a Malaysian population in comparison with non-keratoconic subjects. METHODS: Clinical eye examinations were performed on patients with keratoconus and non-keratoconic subjects after questionnaires were completed. Blood samples were collected and subjected to spectrophotometry analysis of paraoxonase and diazoxonase activities for the determination of the status of PON1 of every individual. RESULTS: Of the 11 keratoconic patients and 55 non-keratoconic control samples collected, eight patients of Indian ethnicity were keratoconic (73%), whereas 33 non-Indians were non-keratoconic (60%; p = 0.047). Paraoxonase activity was lower in Indians compared to the …

Erectogenic Effects Of Clerodendron Capitatum: Involvement Of Phosphodiesterase Type-5 Inhibition, Dr Syam Mohan

Syam Mohan

No abstract provided.

Clausena Excavata Burm. F. (Rutaceae): A Review Of Its Traditional Uses, Pharmacological And Phytochemical Properties., Dr Syam Mohan

Syam Mohan

The present review describes the morphological, traditional, phytochemical and pharmacological aspects of Clausena excavata (Burm. f., Rutaceae). The plant grows wild in the tropical and subtropical parts of Asia and represents one of the richest sources of medicinal natural products. It is intensively used currently in traditional medicine for treatment of different illnesses. One part or a mixture of two or more parts of the plant in the form of powder or liquid doze is usually given to the patient. Phytochemically, many pure compounds from several secondary metabolite groups of C. excavata have been isolated from different parts of the …

Chloroform Fraction Of Centratherum Anthelminticum (L.) Seed Inhibits Tumor Necrosis Factor Alpha And Exhibits Pleotropic Bioactivities: Inhibitory Role In Human Tumor Cells, Dr Syam Mohan

Syam Mohan

We investigated the antioxidant potential, cytotoxic effect, and TNF-α inhibition activity with NF-κB activation response in a chloroformfraction of Centratherum anthelminticum seeds (CACF). The antioxidant property of CACF was evaluated with DPPH, ORAC, and FRAP assays, which demonstrated significant antioxidant activity. The cytotoxicity of CACF was tested using theMTT assay; CACF effective inhibitory concentrations (IC50) for A549, PC-3, MCF-7, and WRL-68 cells were 31.42 ± 5.4, 22.61 ± 1.7, 8.1±0.9, and 54.93±8.3 μg/mL, respectively. CACF effectively and dose-dependently inhibited TNF-α release, in vitro and in vivo. CACF inhibited TNF-α secretion in stimulated RAW264.7macrophage supernatants with an IC50 of 0.012 μg/mL, …

In Vitro Anti-Inflammatory, Cytotoxic And Antioxidant Activities Of Boesenbergin A, A Chalcone Isolated From Boesenbergia Rotunda (L.) (Fingerroot), Dr Syam Mohan

Syam Mohan

The current in vitro study was designed to investigate the anti-inflammatory, cytotoxic and antioxidant activities of boesenbergin A (BA), a chalcone derivative of known structure isolated from Boesenbergia rotunda. Human hepatocellular carcinoma (HepG2), colon adenocarcinoma (HT-29), non-small cell lung cancer (A549), prostate adenocarcinoma (PC3), and normal hepatic cells (WRL-68) were used to evaluate the cytotoxicity of BA using the MTT assay. The antioxidant activity of BA was assessed by the ORAC assay and compared to quercetin as a standard reference antioxidant. ORAC results are reported as the equivalent concentration of Trolox that produces the same level of antioxidant activity as …

Synthesis Of Chalcones With Anticancer Activities., Dr Syam Mohan

Syam Mohan

Several chalcones were synthesized and their in vitro cytotoxicity against various human cell lines, including human breast adenocarcinoma cell line MCF-7, human lung adenocarcinoma cell line A549, human prostate cancer cell line PC3, human adenocarcinoma cell line HT-29 (colorectal cancer) and human normal liver cell line WRL-68 was evaluated. Most of the compounds being active cytotoxic agents, four of them with minimal IC50 values were chosen and studied in detail with MCF-7 cells. The compounds 1, 5, 23, and 25 were capable in eliciting apoptosis in MCF-7 cells as shown by multiparameter cytotoxicity assay and caspase-3/7, -8, and -9 activities …

Cucurbitacin L 2-O- Glucoside Demonstrates Apoptogenesis In Colon Adenocarcinoma Cells (Ht-29): Involvement Of Reactive Oxygen And Nitrogen Species Regulation, Dr Syam Mohan

Syam Mohan

Emerging evidence suggests that reactive oxygen (ROS) and nitrogen (RNS) species can contribute to diverse signalling pathways of inflammatory and tumour cells. Cucurbitacins are a group of highly oxygenated triterpenes. Many plants used in folk medicine to treat cancer have been found to contain cucurbitacins displaying potentially important anti-inflammatory actions. The current study was designed to investigate the anti-ROS and -RNS effects of cucurbitacin L 2-O-β-glucoside (CLG) and the role of these signaling factors in the apoptogenic effects of CLG on human colon cancer cells (HT-29). This natural cucurbitacin was isolated purely from Citrullus lanatus var. citroides (Cucurbitaceae). The results …

Dentatin Induces Apoptosis In Prostate Cancer Cells Via Bcl-2, Bcl-Xl, Survivin Downregulation, Caspase-9, -3/7 Activation And Nf-Kb Inhibition., Dr Syam Mohan

Syam Mohan

This study was set to investigate antiproliferative potential of dentatin (a natural coumarin isolated from Clausena excavata Burm. F) against prostate cancer and to delineate the underlying mechanism of action. Treatment with dentatin dose-dependently inhibited cell growth of PC-3 and LNCaP prostate cancer cell lines, whereas it showed less cytotoxic effects on normal prostate epithelial cell line (RWPE-1). The inhibitory effect of dentatin on prostate cancer cell growth was due to induction of apoptosis as evidenced by Annexin V staining and cell shrinkage. We found that dentatin-mediated accumulation of reactive oxygen species (ROS) and downregulated expression levels of antiapoptotic molecules …

Conformational Equilibrium Of N-Myristoylated Camp-Dependent Protein Kinase A By Molecular Dynamics Simulations, Alessandro Cembran, Larry R. Masterson, Christopher L. Mcclendon, Susan S. Taylor, Jiali Gao, Gianluigi Veglia

Larry Masterson

Lipopolysaccharide Biosynthesis Without The Lipids: Substrate Recognition For Escherichia Coli Heptosyltransferasei, Daniel J. Czyzyk, Cassie Liu, Erika A. Taylor

Erika A. Taylor, Ph.D.

Heptosyltransferase I (HepI) is responsible for the transfer of l-glycero-d-manno-heptose to a 3-deoxy-α-D-oct-2-ulopyranosonic acid (Kdo) of the growing core region of lipopolysaccharide (LPS). The catalytic efficiency of HepI with the fully deacylated analogue of Escherichia coli HepI LipidA is 12-fold greater than with the fully acylated substrate, with a k(cat)/K(m) of 2.7 × 10(6) M(-1) s(-1), compared to a value of 2.2 × 10(5) M(-1) s(-1) for the Kdo(2)-LipidA substrate. Not only is this is the first demonstration that an LPS biosynthetic enzyme is catalytically enhanced by the absence of lipids, this result has significant implications for downstream enzymes that …

The Growth Suppressing Effects Of Girinimbine On Hepg2 Involve Induction Of Apoptosis And Cell Cycle Arrest, Syam Mohan

Syam Mohan

Murraya koenigii is an edible herb widely used in folk medicine. Here we report that girinimbine, a carbazole alkaloid isolated from this plant, inhibited the growth and induced apoptosis in human hepatocellular carcinoma, HepG2 cells. The MTT and LDH assay results showed that girinimbine decreased cell viability and increased cytotoxicity in a dose-and time-dependent manner selectively. Girinimbine-treated HepG2 cells showed typical morphological features of apoptosis, as observed from normal inverted microscopy and Hoechst 33342 assay. Furthermore, girinimbine treatment resulted in DNA fragmentation and elevated levels of caspase-3 in HepG2 cells. Girinimbine treatment also displayed a time-dependent accumulation of the Sub-G(0)/G(1) …

Synthesis And In Vitro Binding Of N,N-Dialkyl-2-Phenylindol-3-Ylglyoxylamides For The Peripheral Benzodiazepine Binding Sites, T. P. Homes, F. Mattner, Paul A. Keller, A. Katsifis

Paul Keller

A series of N,N-dialkyl-2-phenylindol-3-ylglyoxylamides bearing the halogens iodine and bromine were synthesised and their binding affinity for the peripheral benzodiazepine binding sites (PBBS) in rat kidney mitochondrial membranes were evaluated using [3H]-PK11195. Central benzodiazepine receptor (CBR) affinities were also evaluated in rat cortices using 3H-flumazenil to determine their selectivity for PBBS over CBR. The tested compounds had PBBS binding affinities (IC50) ranging from 7.86 nM to 618 nM, with all compounds showing high selectivity over the CBR (CBR IC50 > 5000 nM). Among the 12 compounds tested, those with a diethylamide group were the most potent. The highest affinity iodinated PBBS …

Paraoxonase 1 Activity As A Predictor Of Cardiovascular Disease In Type 2 Diabetes, Rozaida @ Poh Yuen Ying

Rozaida @ Poh Yuen Ying

The role of paraoxonase 1 in cardiovascular disease complications in type 2 diabetes mellitus is not fully understood. We studied paraoxonase activity towards paraoxon in 188 non-diabetic and 140 diabetic subjects using general linear models and univariate analysis. Adjusting for age revealed a reduction in activity towards paraoxon was associated with a significant increase in risk (p=0.023) for cardiovascular disease complications in diabetic patients. Multivariate analysis of two plasma measures of paraoxonase activity using paraoxon and diazoxon also showed reduced paraoxonase activity towards paraoxon was associated with a significant increase in risk (p=0.045) for cardiovascular disease complications in diabetic patients. …

Pharmacology Supplement, Ahmed Mustafa, Ellioott Blumenthal

Ahmed Mustafa Dr.

No abstract provided.

Ppar Agonists Down-Regulate The Expression Of Atp10c Mrna During Adipogenesis, A Peretich, Maria Cekanova Ms, Rndr, Phd, S Hurst, Sj Baek, Madhu Dahr

Maria Cekanova MS, RNDr, PhD

No abstract provided.