Medicine and Health Sciences Commons^™

Guinea Pigging In Philadelphia, Roberto Abadie

Department of Sociology: Faculty Publications

On June 16, 2001, the national press first reported the death of Ellen Roche, a healthy 24-year-old who volunteered for an asthma study at Johns Hopkins University. The story revealed that a few days into the trial she felt very sick, was discharged, and sent home. Within some hours she checked into the emergency room at a local hospital and fell into a coma. Ellen remained in this state until her death a month later. She had received $375 for participating in seven to nine sessions as an outpatient in the clinical drug study that resulted in her death.

This …

Understanding Of Functions Of Selenoproteins And Dietary Selenium By Using Animal Models, Marina V. Kasaikina

Department of Biochemistry: Dissertations, Theses, and Student Research

Selenium (Se) is a trace element that is incorporated into proteins in the form of the 21^st amino acid, selenocysteine (Sec). Se supplementation was reported to have beneficial roles in prevention of cardiovascular and muscle disorders, cancer prevention and enhancement of the immune function. However, recent studies also showed that excessive dietary Se increases the risk of development of type 2 diabetes mellitus. Thus, better understanding of Se and selenoprotein functions is required. We used three approaches to address this problem.

First, we used high-throughput sequencing to examine composition of the gut microflora in mice maintained on selenium-deficient, selenium-sufficient, …

Affinity Chromatography: A Review Of Clinical Applications, David S. Hage

David Hage Publications

Affinity chromatography is a type of liquid chromatography that makes use of biological-like interactions for the separation and specific analysis of sample components. This review describes the basic principles of affinity chromatography and examines its use in the testing of clinical samples, with an emphasis on HPLCbased methods. Some traditional applications of this approach include the use of boronate, lectin, protein A or protein G, and immunoaffinity supports for the direct quantification of solutes. Newer techniques that use antibody-based columns for on- or off-line sample extraction are examined in detail, as are methods that use affinity chromatography in combination with …

Improved Recovery Of A Radlolabeled Peptide With An Albumin-Treated Reversed-Phase Hplc Column, David S. Hage, Robert L. Taylor, Pai C. Kao

David Hage Publications

Reversed-phase high-performance liquid chromatography (RP-HPLC) is an important tool in the purification of radiolabeled peptides and proteins for immunoassay. However, for some proteins and peptides it is difficult to achieve reproducible behavior in RP-HPLC because of the low recovery of these compounds. Factors that can be varied to improve recovery include the strength or pH of the mobile phase, the chain length and spacing of groups on the reversed-phase support, and the flow rate or steepness of the elution gradient (1-5). ... In summary, we obtained better recovery and more reproducible chromatographic behavior for labeled 1-34 PTHrP with an albumin-pretreated …

Intact Parathyroid Hormone: Performance And Clinical Utility Of An Automated Assay Based On High-Performance Immunoaffinity Chromatography And Chemiluminescence Detection, David S. Hage, Bob Taylor, Pai C. Kao

David Hage Publications

The performance and clinical utility of an automated assay of intact parathyroid hormone (parathyrin, PTH) are evaluated. The method is based on the extraction of PTH from plasma by an HPLC column containing immobilized anti-(44-68 PTH) antibodies. The PTH retained is detected with a postcolumn reactor and use of anti-(1--34 PTH) chemiluminescent-labeled antibodies. The total cycle time of the assay is 6.5 mm per injection after a 1-h incubation.The lower limit of detection for PTH in a 66-pL plasma sample was 0.5 pmol/L based on peak heights and 0.2 pmol/L based on peak areas. Mean analytical recovery for PTH added …

The Chemistry Of Pesticides, Walter R. Benson

Food and Drug Administration Papers

INTRODUCTION This review is limited to the structures and a few reactions of the pesticides mainly insecticides-that affect mammalian systems and that are the subject of papers by other authors in this monograph. There is no attempt to give a complete review of the chemistry of pesticides. It is intended only to show the breadth and depth of pesticide chemistry through the use of examples. With proper use of the references, and of the papers by Crosby, Freed and Montgomery, and Owens in this monograph, the reader will be able to find information for other chemicals.

NOMENCLATURE Pesticides or economic …

Quantitative Calculation Of Gas Chromatographic Peaks In Pesticide Residue Analyses, Jean A. Gaul

Food and Drug Administration Papers

Comparison of five methods for calculating gas chromatographic peaks (disc integration, triangulation, peak height X width at half height, R_t X peak height, and peak height) shows no significant difference in the calculated results when aldrin, heptachlor epoxide, and dieldrin are injected into a gas chromatograph equipped with electron capture detector.

Problems are associated with the calculation of toxaphene, chlordane, DDT, and BHC. The author makes suggestions for calculating these four residues when present individually and in combinations with other pesticides. Use of the last four toxaphene peaks compares favorably with results obtained by using the entire toxaphene curve. …

Analysis Of Pesticide Residues By Polarography, Raymond J. Gajan

Food and Drug Administration Papers

Polarography is a rapid, sensitive, and relatively specific technique that can be applied to pesticide residue analysis. The technique should also prove a valuable tool in overall pesticide research, such as monitoring new columns, studying kinetics, identifying and determining metabolites, assaying primary pesticide standards, and conducting stability studies.

Diphenylamine-Zinc Chloride As A Chromogenic Agent For The Detection Of A Mixture Of Ddt, Chlordane, And Toxaphene On Thin Layer Chromatograms, Lewis J. Faucheux Jr.

Food and Drug Administration Papers

Diphenylamine-ZnCI, has been evaluated as a chromogenic agent for detection of toxaphene, DDT, and chlordane on Al₂O₃ a thin layer plates. Characteristic colors were obtained for these pesticides; a lower level of about 5 μg was detectable. Color reactions of 34 pesticides at the 20 μg level are presented.

Pesticide Residues, J. William Cook, Sidney Williams

Food and Drug Administration Papers

METHODOLOGY for residue analysis has advanced rapidly during the current review period, from November 1962 through October 1964. Notable progress has been made in the development and refinement of methods of analysis by which any or all of a large number of pesticide residue chemicals can be detected and measured in one general operation. This is of particular significance because great interest has developed-outside the scientific community as well as within - in the possible presence of pesticide chemicals in all parts of our environment, including man himself. Only by the use of improved methodology will it be possible to …

Exposure To Parathion Effect On General Population And Asthmatics, Robert S. Ganelin, Cipriano Cueto Jr., G. Allen Mail

Food and Drug Administration Papers

There has been much lay and medical concern regarding toxic effects of insecticides on the general population. In addition to direct toxic effects, it is suspected that insecticidal application has deleterious physical effects on persons with respiratory diseases. To evaluate some of these problems, the authors have attempted to quantitate actual absorption, symptoms, and laboratory evidence of intoxication in persons with varying degrees of exposure to parathion. By means of controlled observations, the respiratory effect of application of this compound on persons with bronchial asthma was also measured. The results suggest that the effect of this chemical on the general …

Application Of Oscillographic Polarography To Determination Of Organic Phosphorus Pesticide Residues, Raymond J. Gajan

Food and Drug Administration Papers

Some organic phosphorus pesticides have been determined successfully by polarography (1-7). However, in most cases the methods were used to determine the pesticide in commercial formulations. Little has been reported on the polarographic determination of microgram amounts of these pesticides such as those encountered in pesticide residue analysis.

Many of the methods used for the determination of these pesticides are nonspecific. They are based on cholinesterase assay (8- 12), radioactive tracer analysis (13, 14), total phosphorus (15-17), and paper chromatography (18-24).

In this paper we will discuss the polarography of Systox, Di-Syston, and· Thimet and some of their oxidation products, …

Swine Brucellosis And Human Health, Us Public Health Service

Food and Drug Administration Papers

Swine brucellosis is caused by Brucella suis, a strain of bacteria which also cau ses human brucellosis, or undulant fever. T his disease is an imp 0 r tan t public health problem which affects thousands of farmers, livestock handlers, meat processors, and butchers .. The U. S. Department of Agriculture estimates that 6.15 percent of the 1.8 million swine herds in the Nation are infected with brucellosis. This represents about 131,000 in f e c ted herds on farms, where some 579,000 farm people come into daily c ontact with these herds. The infection rate among these rural persons …