Biomedical subjects

J Dorner

Publications and source records attributed to J Dorner.

6 recordsLinked to original sources

PubMed2003

LeukoScan for imaging infection in different clinical settings: a retrospective evaluation and extended review of the literature.

PURPOSE: The aim of the current study was to determine the overall diagnostic accuracy of Tc-99m-labeled antigranulocyte monoclonal antibody Fab' fragments (LeukoScan) for the routine detection of bone and soft tissue infections in a retrospective evaluation. PATIENTS AND METHODS: 138 patients (63 men, 75 women; mean age, 58.29 +/- 25.38 years) with fever of unknown origin and possible endocarditis (n = 59), infection of arthroplastic joints (n = 20), arthritis (n = 16), peripheral (n = 15) and central bone infections (n = 14), soft tissue infection (n = 6), appendicitis (n = 4), pericarditis (n = 2), or vascular graft infection (n = 2) underwent imaging after injection of 555 to 925 MBq (15 to 25 mCi) Tc-99m-labeled antigranulocyte monoclonal antibody Fab' fragments (LeukoScan). RESULTS: True-positive results were found in 63 of 81 lesions. The overall sensitivity and specificity were 76% and 84%, respectively. In arthritis, seven of seven foci could be detected, whereas false-negative results were found in infections of the femoral bone in three of nine lesions and in periprosthetic infections of long bones in three of eight lesions. Good results were found in five of six soft-tissue infections, in four of six patients with endocarditis, in three of four atypical cases of appendicitis, in two of two infected vascular grafts, and in one of one patient with pericarditis. Subacute and chronic infections of the spine always showed photopenic areas in eight of eight patients. If photopenic lesions were included as diagnostic criteria, the sensitivity and specificity were 88% and 67%, respectively. CONCLUSIONS: Tc-99m-labeled antigranulocyte monoclonal antibody Fab' fragments can be used for imaging acute infections of peripheral bones and soft tissues. False-negative results are likely in patients with chronic infections. Sensitivity can be increased while decreasing specificity by including photopenic lesions in the spine as diagnostic criteria for localizing disease.

Adult↗

PubMed1994

Application of short-lived radionuclides in neutron activation analysis of biological and environmental samples.

The application of short-lived nuclides, especially in connection with the 6LiD-converter, in biological and environmental samples is demonstrated on I and Br determination in human urine, on I in pet food, and on the analysis of all the halogens in volcanic gases in a single activation. Trace element determination in lichens indicates polluted and unpolluted areas. The use of the .74-s 38mCl enables the rapid screening of great number of samples.

Animal Feed↗

PubMed1986

The mechanism by which cyclopiazonic acid potentiates accumulation of tetraphenylphosphonium in cultured renal epithelial cells.

Cyclopiazonic acid (CPA), a fungal metabolite produced by Aspergillus and Penicillium, potentiated the accumulation of the quaternary cation tetraphenylphosphonium (TPP+) in cultured pig renal epithelial cells. This is the first report of a natural product mediating the tight and apparently nonsaturable binding of a membrane potential probe to subcellular compartments. The potentiated TPP+ accumulation was dose dependent, nonsaturable, and not a result of hyperpolarization across the plasma membrane. Cyclopiazonic acid-potentiated accumulation was completely inhibited by the protonophore carbonylcyanide-m-chlorophenylhydrazone (CCCP). Dinitrophenol (DNP), tetrahexylammonium (THA), and n-ethylmaleimide (NEM) were also effective inhibitors of CPA-potentiated TPP+ accumulation. Although CPA-potentiated TPP+ uptake appeared to be energy dependent, TPP+ efflux (in the presence of CCCP) from CPA-treated cells was incomplete and most of the TPP+ accumulated in the presence of CPA was tightly bound. Dicyclohexylcarbodiimide (DCC), verapamil, and monensin also stimulated TPP+ accumulation, but the TPP+ which accumulated in the presence of these compounds was not tightly bound. As with controls, fractionation of cells which had accumulated TPP+ in the presence of DCC, verapamil, or monensin always resulted in near complete recovery (greater than 93%) of the TPP+ in the cytosolic fraction, whereas with CPA, greater than 88% of the TPP+ was recovered noncovalently bound in the plasma membrane and mitochondrial fractions. These results are consistent with the hypothesis that CPA-potentiated TPP+ accumulation is a result of potentiated partitioning of TPP+ into the plasma membranes and mitochondria of LLC-PK1 cells.

Animals↗

PubMed1985

Toxicity of the mycotoxin, cyclopiazonic acid, to Sprague-Dawley rats.

Groups of male Sprague-Dawley rats received po doses of cyclopiazonic acid (CPA) on four consecutive days at 0.0, 0.2, 2.0, 4.0, or 8.0 mg kg-1 days-1. Clinical signs of toxicity were observed only in the two highest dose groups. Rats in the highest dose group exhibited abnormal behavior, diarrhea, and other signs of toxicity after several days of dosing, and most were moribund before the last scheduled dose was administered. Liver and spleen were more severely affected than other organs in the two highest dose groups. Livers contained diffuse pycnotic nuclei and, in some high-dose rats, focal areas of coagulative necrosis. In the high-dose group aspartate and alanine aminotransferase activities were elevated, cytochrome P-450 concentration was decreased, and glutathione S-transferase activity was unchanged. Spleens were hemorrhagic and white pulp contained necrotic lymphocytes. White cell counts were decreased in a dose-related manner in the two highest dose groups. The gastrointestinal tract of high-dose rats contained pycnotic nuclei, and sites of necrosis were observed in stomach, but these lesions were limited to several animals, and were generally mild. Pathologic changes in conjunction with decreased feed and water intake probably contributed to the general deterioration of high-dose rats that resulted in death.

Administration, Oral↗

PubMed1985

Effects of cyclopiazonic acid on the ultrastructure of rat liver.

Groups of Sprague-Dawley rats were dosed per os for 4 consecutive days with 0.0, 0.2, 2.0 or 4.0 mg cyclopiazonic acid (CPA)/kg body weight/day, and killed on the fifth day. Sections of liver were prepared for electron microscopic examination. Dilatation of the rough endoplasmic reticulum was observed in all hepatocytes examined from the 2 highest dose groups, and in about 25% of liver cells from the 0.2 mg CPA/kg/day group. Vesiculation of the rough endoplasmic reticulum also occurred in these groups, an increasing amount of vesiculation being observed with increasing dosage. Control sections exhibited neither of these characteristics. No proliferation of smooth endoplasmic reticulum, or blockage of bile canaliculi was observed in any group. Lysing cells were present only in the 4.0 mg CPA/kg/day group; mitochondria in the 2.0 and 4.0 mg CPA/kg/day dose groups were swollen. Nuclei were ultrastructurally normal in all groups. The primary cellular effect of CPA was on the endoplasmic reticulum, even at relatively low doses. Possible interactions of CPA with other toxins likely to be produced by the same fungus, such as aflatoxin, are considered.

Animals↗

PubMedDate not supplied

Computerized test development software. A comparative review updated.

This article provides a comparative review of nine commercially available software programs: A+ Test Manager and Test Taker, CATSoftware, Diploma 97, Examaker for Windows, FastTEST, Microtest Pro, Pedagogue, Question Mark, and Test Construction Set. Issues for using test development software are covered including security, pedagogical uses, and test design and administration. Nurse educators are encouraged to consider the unique needs of each setting when selecting a software package to support test development and administration.

Computer-Assisted Instruction↗