High-performance liquid chromatographic method development and validation for the simultaneous quantitation of naproxen sodium and pseudoephedrine hydrochloride impurities.
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A reversed-phase high-performance liquid chromatographic procedure for the simultaneous determination of impurities associated with pseudoephedrine hydrochloride (PSEH) and naproxen sodium (NapNa) is developed and validated. The method is developed using a Waters Spherisorb cyano column (5 microm, 250 x 4.6 mm). An isocratic elution in a water-acetonitrile-methanol-triethylamine mixture (850:75:75:5) is adjusted to a pH of 3.7 +/- 0.02 with formic acid as the mobile phase. The UV detection was set at 260 nm, and the wavelength was switched to 235 nm before the elution of the last component, 2-ethyl-6-methoxy-naphthalene (EMN). The method is shown to be linear at a concentration range of 0.24 to 1.92 microg/mL for benzaldehyde, benzoic acid, and 2-(methylamino)-propiophenone hydrochloride, which are known impurities of PSEH. The NapNa impurities, 2-(6'-hydroxy-2'-naphthyl) propionic acid, 2-hydroxy-6-methoxy-naphthalene, 1-(6'-methoxy-2'-naphthyl) ethanol, 2-acetyl-6-methoxy-naphthalene, and EMN are also demonstrated to be linear at a concentration range of 0.44 to 3.52 microg/mL. Under the chromatographic conditions of the method, all impurities are resolved from the active components. (+info)
Molecular analyses of oral polio vaccine samples.
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It has been suggested that the human immunodeficiency virus (HIV), and thus the acquired immunodeficiency syndrome (AIDS) it causes, was inadvertently introduced to humans by the use of an oral polio vaccine (OPV) during a vaccination campaign launched by the Wistar Institute, Philadelphia, PA, USA, in the Belgian Congo in 1958 and 1959. The "OPV/AIDS hypothesis" suggests that the OPV used in this campaign was produced in chimpanzee kidney epithelial cell cultures rather than in monkey kidney cell cultures, as stated by H. Koprowski and co-workers, who produced the OPV. If chimpanzee cells were indeed used, this would lend support to the OPV/AIDS hypothesis, since chimpanzees harbor a simian immunodeficiency virus, widely accepted to be the origin of HIV-1. We analyzed several early OPV pools and found no evidence for the presence of chimpanzee DNA; by contrast, monkey DNA is present. (+info)
Serratia liquefaciens bloodstream infections from contamination of epoetin alfa at a hemodialysis center.
(51/744)
BACKGROUND: In a one month period, 10 Serratia liquefaciens bloodstream infections and 6 pyrogenic reactions occurred in outpatients at a hemodialysis center. METHODS: We performed a cohort study of all hemodialysis sessions on days that staff members reported S. liquefaciens bloodstream infections or pyrogenic reactions. We reviewed procedures and cultured samples of water, medications, soaps, and hand lotions and swabs from the hands of personnel. RESULTS: We analyzed 208 sessions involving 48 patients. In 12 sessions, patients had S. liquefaciens bloodstream infections, and in 8, patients had pyrogenic reactions without bloodstream infection. Sessions with infections or reactions were associated with higher median doses of epoetin alfa than the 188 other sessions (6500 vs. 4000 U, P=0.03) and were more common during afternoon or evening shifts than morning shifts (P=0.03). Sessions with infections or reactions were associated with doses of epoetin alfa of more than 4000 U (multivariate odds ratio, 4.0; 95 percent confidence interval, 1.3 to 12.3). A review of procedures revealed that preservative-free, single-use vials of epoetin alfa were punctured multiple times, and residual epoetin alfa from multiple vials was pooled and administered to patients. S. liquefaciens was isolated from pooled epoetin alfa, empty vials of epoetin alfa that had been pooled, antibacterial soap, and hand lotion. All the isolates were identical by pulsed-field gel electrophoresis. After the practice of pooling epoetin alfa was discontinued and the contaminated soap and lotion were replaced, no further S. liquefaciens bloodstream infections or pyrogenic reactions occurred at this hemodialysis facility. CONCLUSIONS: Puncturing single-use vials multiple times and pooling preservative-free epoetin alfa caused this outbreak of bloodstream infections in a hemodialysis unit. To prevent similar outbreaks, medical personnel should follow the manufacturer's guidelines for the use of preservative-free medications. (+info)
Changes in the disintegration properties of some brands of paracetamol tablets inoculated with four bacterial species.
(52/744)
Four most common brands of paracetamol (4-aceta-midophenol) tablets were examined for the changes in their disintegration properties after inoculation with Staphylococcus aureus, Bacillus cereus, Klebsiella aerogenes and Pseudomonas aeruginosa and incubating for 5 weeks. The disintegration times varied from one brand to the other, reaching maximum values of 72 min., 82 min., 110 min. and 120 min. for S. aureus, B. cereus, P. aeruginosa and Klebsiella aerogenes, respectively. All brands of paracetamol tablets revealed the presence of cotton wool-like fibrils which were seen to be interwoven within the tablets' matrices and these were believed to have caused the higher disintegration times. (+info)
The Jezierski papers: live polio vaccine development in colobus monkey cells but not chimpanzee cells in the Belgian Congo, 1952-1958.
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A reading of ten relevant papers by Alexandre Jezierski provides evidence for the only attempt in Central Africa to develop a live oral polio vaccine (OPV) from growing reference wild polio strains to 210 passages in colobus monkey tissue culture, and experimental administration to about 25 humans. Chimpanzees were used as a human model, but their tissues or kidneys were absent from the passage and production line of the proposed vaccine. Thus, the implication published by Hooper that Jezierski had produced a candidate OPV that might have contained chimpanzee viruses, possibly simian immunodeficiency virus cpz or the precursor of human immunodeficiency virus-1 group M, is incorrect. (+info)
Polio vaccine and retroviruses.
(54/744)
In this paper we consider the main steps in the process of manufacture of oral polio vaccine and assess the probable clearance factor for HIV retrovirus at each step. We conclude that the processes employed would have eliminated retrovirus contamination for all practical purposes. (+info)
Responsibility for truth in research.
(55/744)
For over half a century, cell cultures derived from animals and humans have served researchers in various fields. To this day, cross-contamination of cultures has plagued many researchers, often leading to mistaken results, retractions of results, cover-ups and some out-and-out falsification of data and results following inadvertent use of the wrong cells. Also, during years of examining cultures for purity we learned that many virologists were not too concerned about the specificity of the cultures they used to propagate the particular virus under study as long as the substrate (whatever it might have been) gave optimal virus yield. Polio virus propagates in primate cells, and much research has involved cells from man and various species of primates. In the 1950s a large number of chimpanzees were held in captivity in Africa for extensive studies of the efficacy of polio vaccine in production at the Wistar Institute in Philadelphia and elsewhere. Chimpanzee tissues, particularly kidneys, were thus readily available and could have also provided substrates for polio virus production, since little was known about the purity of substrates and little attention was paid to their specificity at that time. (+info)
Occurrence of coring in insulin vials and possibility of rubber piece contamination by self-injection.
(56/744)
Coring is reported to occur because rubber pieces are shaved off from a rubber stopper when a needle is inserted into the rubber stopper of transfusion liquid formulation. We verified whether coring really occurs in insulin vials of self-injecting patients. We collected insulin cartridges from 30 hospitalized patients and used the primary injection (trial injection), the secondary injection and the cartridge remaining preparation as samples. We observed the rubber pieces using a microscope and measured the shape, number of pieces. The occurrence rate of coring was 73% for the primary injection, 47% for the secondary injection and 97% for the cartridge remaining preparation. The rubber pieces in the primary injection and the secondary injection which went through the needle are mostly in aggregate shape and the rubber pieces in the cartridge remaining preparation which did not go through the needle are mostly in needle-like shape. A number of small rubber pieces are found in both the primary injection and the secondary injection, indicating a high possibility that rubber pieces may be injected under subcutaneous tissue. The coring is considered to occur because needles are repeatedly inserted and rotated at the same spot. It is required to improve the structure to mount a needle to the pen-type injector in future. Coring is a very serious problem from the medical and pharmaceutical points of view. Further study should be made on the implication to latex allergy and lipodystrophy. (+info)