Comparison of the fluorescent polarization (TDx) and the enzymatic competitive (EMIT 2000) immune assays for the measurement of cyclosporin A blood concentration

Evaluation of Cyclosporin A (CyA) blood concentration is imperative in solid organ transplantation in order to achieve maximal immunosuppression with the least side effects. We compared the results of whole blood concentrations of CyA in 50 blood samples simultaneously evaluated by the fluorescent polarization immune assay (TDx) and the enzymatic competitive immune assay (EMIT 2000). There was a strong correlation between both kits for any range of CyA blood concentration (R=0.99, p<0.001). The within-run and between-days coefficient of variation were less than 4% for both assays. The cost for each CyA measurement was 50% lower for the EMIT assay when compared to the TDx assay. We concluded that the EMIT is as accurate as the TDx in measuring CyA blood concentration and has the advantage of a lower cost, as well as the possibility of widespread access to the EMIT methodology in contrast to the TDx equipment, allowing the laboratory to perform several routines within a working day.

Vancomycin monitoring in term newborns: comparison of peak and trough serum concentrations determined by high performance liquid chromatography and fluorescence polarization immunoassay

INTRODUCTION: Peak and trough serum concentrations of vancomycin were determined in term newborn infants with confirmed or suspected Staphylococcus sp sepsis by high performance liquid chromatography and flourescence polarization immunoassay. OBJECTIVE: To statistically compare the results of the high performance liquid chromatography and flourescence polarization immunoassay techniques for measuring serum vancomycin concentrations. METHODS: Eighteen peak and 20 trough serum samples were assayed for vancomycin concentrations using high performance liquid chromatography and flourescence polarization immunoassay from October 1995 to October 1997. RESULTS: The linear correlation coefficients for high performance liquid chromatography and flourescence polarization immunoassay were 0.27 (peak, P = 0.110) and 0.26 (trough, P = 0.1045) respectively, which were not statistically significant. CONCLUSION: There was wide variation in serum vancomycin concentrations determined by high performance liquid chromatography as compared with those determined by flourescence polarization immunoassay. There was no recognizable pattern in the variability; in an apparently random fashion, the high performance liquid chromatography measurement was sometimes substantially higher than the flourescence polarization immunoassay measurement, and at other times it was substantially lower.

Comparasion of polyacrylamide gel electrophoresis (PAGE), immuno-electron microscopy (IEM) and enzyme immunoassay (EIA) for the rapid diagnosis of rotavirus infection in children

Detection of rotavirus RNA by polyacrylamide gel electrophoresis (PAGE) proved to be a highly sensitive and rapid diagnostic test. A comparison of this assay with immuno-electron microscopy (IEM) and enzyme immunoassay (EIA) in 245 faeces from children with gastroenteritis revealed complete agreement between the three assays in 238 (97.14%) samples. Among 75 samples positive in at least one of the three assays, negative results were observed in 5 (6.48%) by PAGE, in 6 (6.76%) by EIA and in none by IEM. Silver staining greatly increased the sensitivity of the PAGE assay. We conclude that although IEM remains the most sensitive and rapid rotavirus diagnostic assay, the PAGE technique has many advantages in its favour, including the non-requirement of expensive equipment, the use of only chemically defined reagents and the capacity to distinguish virus subgroup and variants and to detect non-crossreactive rotaviruses which are missed in serological assays.

Rapid detection by transmission electron microscopy of mycoplasma contamination in sera and cell cultures

Transmission electon microscopy has been employed for the rapid detection of mycoplasma in sera and cell cultures. High speed centrifugation of sera or low speed centrifugation of cell debris, followed by negative staining of the resuspended pellet, detected mycoplasma contamination more frequently than a culture method followed by direct fluorescence (DAPI), which was used as a control procedure. The appearance of the mycoplasma cell border and content gives some information about particle viability.

Scanning electron microscopy of the egg and the first instar larva of Dermatobia hominis (Diptera, cuterebridae)

The egg and the first instar larva of Dermatobia hominis were described based on observation with a scanning electron microscope.

Morphological evidence by scanning electron microscopy of excretion of metacyclic forms of Trypanosoma cruzi in vector's urine

Comparision by scanning electron microscopy (SEM) of Trypanosoma cruzi flagellates attached to the cuticle of the rectal gland of infected Dipetalogaster maxima nymphs, showed marked differences before amd after feeding. Before feeding numerous metacyclic trypomastigotes were observed among the abundant epimastigotes that formed the carpet of flagellates. On the other hand, in insects that were allowed to urinate for 24 hours after a meal, the metacyclics were scarce,indicating that they had been detached by the urine flow. An asymetric type of cell division, probably originating both an epi-and a trypomastigote, was occasionally observed. The occurrence of swellings at different levels of the flagella of epimastigotes suggests that secondary sites of attachment may be common.

Scanning electron microscopy of the antennal sensilla in female Culicoides paraensis (Diptera: Ceratopogonidae)

We studied by sanning electron microscopy the number, types, structure and distribution of the antennal sensilla of the medical important ceratopogonid Culicoides paraensis (Goeldi). There are about 174 sense organs on the antenmal flagellum which are classified as sensilla chaetica; sharp-tipped and blunt-tipped (type I and II) sensilla trichodea; sensilla basiconica; sensilla coeloconica; sensilla ampullacea and styloconic-type sensilla. The role of antennal sensory organs are discussed regarding the host preference of the biting midges.

Scanning eletron microscopy of the first instar larvae of Sarcodexia lambens and Peckia chrysostoma (Diptera: Sarcophagidae)

The first instar larvae of Sarcodexia lambens (Wiedemann, 1830) and Peckia chrysostoma (Wiedemann, 1830) dissected from females reared in laboratory, are described under scanning electron microscope (SEM).

Scanning electron microscopy of the male genitalia of Sarcophagidae (Diptera)

The male genitalia of nine species of Sarcophagidae (Diptera) - Goniophyto honsuensis Rohdendorf, 1962, Tricharaea brevicornis (Wiedemann, 1830), Chaetoravinia derelicta (Walker, 1852), Austrohartigia spinigena (Rondani, 1864), Chrysagria duodecimpunctata Townsend, 1935, Boettcheria bisetosa Parker, 1914, Lipoptilocnema lanei Townsend, 1934, L. crispina (Lopes, 1938) and Euboettcheria alvarengai Lopes & Tibana, 1982 - were examined by scanning electron microscope (SEM) and the main morphological features are descirbed.

Scanning electron microscopy of the dorsal vessel of Panstrongylus megistus (Burmeister, 1835) (Hemiptera: Reduviidae)

In this study we analyzed the microanatomy of the dorsal vessel of the triatomine Panstrongylus megistus. The organ is a tuble anatomically divided into an anterior aorta anad a posterior heart, connected to the body wall through 8 pairs of alary muscles. The heart is divided in 3 chambers by means of 2 pairs of cardiac valves. a pair of ostia can be observed in the lateral wall of each chamber. A bundle of nerve fibers was found outside the organ, running dorsally along its major axis. A group of longitudinal muscular fibers was found in the ventral portion of the vessel. The vessel was found to be lined both internally and externally by pericardial cells covered by a thin laminar membrane. Inseide the vessel the pericardial cells were disposed in layers and on the outside they formed clusters or rows.

Description of Trichuris travassosi n. sp. (Nematoda:Trichurinae) from a brasilian rodent, by light and scanning electron microscopy

A new species of a trichurid nematode Trichuris travassosi n. sp., recovered from a wild rodent in the State of Rio Grande do Sul, Brazil, is described and compared to T. myocastoris (Enigk, 1933) and their differentiation was on the basis of detailed morphometrical study. Oryzomys nigripes (Olfers, 1818) is a new host record for the genus. The denomination spicular prepuce is proposed to designate the structure previously named spicular sheath and, conversely, spicular sheath to indicate the cuticle that convers the spicule.

Report of Balanorchis anastrophus in Pará state with surface topography by scanning electron microscopy

Balanorchis anastrophus Fischoeder, 1901 from the reticulum from Bos taurus is reported for the first time in State of Pará, Brazil. The surface topography as revealed by scanning electron microscopy is presented.