In vitro screening as an anthelmintic discovery pipeline for Calicophoron daubneyi: nutritive media and rumen environment-based approaches.

Paramphistomosis can lead to morbidity and mortality of ruminant livestock within tropical and sub-tropical climates. In recent decades, rumen fluke has become an emerging infection in temperate climates across Western Europe, with Calicophoron daubneyi, the primary species present. Clinical outbreaks with C. daubneyi larvae are reported and adults might be responsible for production losses. There is not currently a widely licensed anthelmintic product available to control C. daubneyi. In this study, three existing flukicide anthelmintics were tested for efficacy against mature C. daubneyi, comparing a standard in vitro culturing assay and a new more relevant rumen fluid based in vitro compound screening protocol. The new rumen based screen confirmed that oxyclozanide was active against adult C. daubneyi and identified activity with praziquantel. The study highlighted the downstream value of incorporating relevant in vitro screening for anthelmintic discovery pipelines.

The novel allele, HLA-B*07:68:02, identified in a German cord blood donor and her father.

The novel allele HLA-B*07:68:02 identified in two related individuals of Caucasian origin is described.

Human neutrophil alloantigen genotype frequencies among blood donors with Turkish and German descent.

Antibodies against the human neutrophil antigens (HNA) are able to stimulate transfusion reactions, autoimmune and neonatal neutropenia. The aim of this study was to determine the HNA allele frequencies in the largest ethnic minority group in Germany in comparison with the German population for predicting the risk of alloimmunization and associated transfusion reactions, as well as the risk of developing neonatal neutropenia for the newborn of racial mixed couples. However, there exists no data about HNA genotype distribution in Turkish population. DNA was isolated from blood samples of 119 German and 118 Turkish blood donors and typed them for HNA-1, -3, -4, and -5 by using a commercial polymerase chain reaction kit with sequence-specific primers (SSP-PCR) and compared the HNA genotype distribution of both groups. In German blood donors, the gene frequencies for HNA-1a and HNA-1b were 0.391 and 0.601, for HNA-3a and -3b, 0.744 and 0.256, for HNA-4a and -4b, 0.908 and 0.092, and for HNA-5a and -5bw, 0.731 and 0.269. In Turkish blood donors, we observed 0.420/0.564, 0.737/0.263, 0.881/0.119, and 0.754/0.246 for HNA-1a/1b, -3a/3b, -4a/4b, and -5a/5bw. No statistic significant difference between genotypes in these populations was observed. This study is the first to report HNA gene frequencies in a Turkish population. It showed that there is no difference of HNA genotype in blood donors with Turkish descent in comparison with German blood donors. The alternating transfusion of blood and blood components is no increased risk for developing alloantibodies against HNA antigens. In pregnancy of mixed couples no special screening programs for HNA are necessary.

Influence of late irradiation on the in vitro RBC storage variables of leucoreduced RBCs in SAGM additive solution.

BACKGROUND: There exists only few data on in vitro and in vivo effects of gamma irradiation of leucoreduced red blood cells (RBCs). Reported studies reflect the effects of early irradiation and subsequent storage. The effects of irradiation on RBCs shortly before the end of their shelf-life have not been examined. STUDY DESIGN AND METHODS: We studied 160 RBC units that were stored in the additive solution saline-adenine-glucose-mannitol and leucoreduced on the collection day. Forty components were irradiated on day +14 with 30 Gy, 40 on day +28, 40 on day +35, and 40 served as nonirradiated controls. In vitro evaluation of all units was performed on days +3, +7, +14, +21, +28, +35, and +42 from the collection day. RESULTS: Gamma irradiation induced leakage of potassium ions and lactate dehydrogenase and enhanced in vitro haemolysis rate in the irradiated components, which started to increase faster than that of nonirradiated RBCs from the day of irradiation, i.e. from day +14 in units that were irradiated on day +14, from day +28 in units that were irradiated on day +28, and from day +35 in units that were irradiated on day +35. CONCLUSIONS: This study presents data on the in vitro quality of leucoreduced RBCs that have been irradiated on days +14, +28, or +35 after collection. Our findings support the proposal that the current limitation of the age of RBCs on the day of gamma irradiation may be replaced by staged limitations depending on the time of irradiation.

Influence of irradiation on in vitro red-blood-cell (RBC) storage variables of leucoreduced RBCs in additive solution PAGGS-M.

BACKGROUND: The effect of gamma irradiation on leucoreduced red-blood-cells (RBCs) stored in an additive solution (AS) containing phosphate, adenine, glucose, guanosine, saline and mannitol (PAGGS-M) has not yet been studied, and there are different recommendations about storage time of leucoreduced RBCs after irradiation. STUDY DESIGN AND METHODS: We studied 63 leucoreduced RBC units. All RBCs were stored in AS PAGGS-M and leucoreduced on the collection day. Twenty-one components were irradiated on Day +14 with 30 Gy and 22 served as non-irradiated controls. Samples were drawn and analysed from these 43 units on Day +7, +14, +21, +28, +35, +42 and +49 from the collection day. From 20 units, no samples were taken earlier than on Day +49. Of these, 10 components had been irradiated on Day +14 with 30 Gy and 10 served as non-irradiated controls. RESULTS: Gamma irradiation induced an enhanced in vitro haemolysis rate in the irradiated components. One of the irradiated units showed a haemolysis rate over the recommended limit of 0·8% on Day +42 and four on Day +49. The leakage of potassium ions from irradiated RBCs started to increase faster than that of unirradiated RBCs from the day of irradiation. Lactate dehydrogenase levels increased faster in irradiated units 3 weeks after irradiation. We showed that taking samples weekly does not affect the final result. CONCLUSIONS: Our findings show that the European recommendations should not be changed in regard to the limitation of the storageability after irradiation of leucoreduced RBCs. The damage after irradiation and storage cannot be prevented by using the high-quality AS PAGGS-M.

Microarray analysis of placental tissue in intrauterine growth restriction.

OBJECTIVE: Besides foetal or maternal disorders, placental dysfunction is a major cause of intrauterine growth restriction (IUGR). Although numerous macro- and histopathological changes have been described, little is known about the precise aetiology and the contribution of foetal/placental genes in this disorder. DESIGN: Placental tissues of 20 IUGR and control neonates were analysed by microarray technique. Four of the regulated genes with possible relevance in the pathogenesis of IUGR and its consequences were further studied in placentas of 27 IUGR and 35 control newborns. RESULTS: Elevated gene expression of leptin, corticotrophin-releasing hormone (CRH), and IGF-binding protein-1 (IGFBP-1) in IUGR placentas could be confirmed in the larger group by real-time PCR, whereas prolactin showed no significant difference. Accordingly, protein expression of leptin and IGFBP-1 depicted by Western blot was elevated in IUGR, prolactin was not different. Birthweight standard deviation score (SDS) correlated negatively to leptin, IGFBP-1, and CRH, whereas placental weight correlated only to IGFBP-1. Leptin correlated negatively to gestational age of IUGR patients and positively to placental score, a marker of severity of impaired foeto-placental circulation. CONCLUSIONS: As confirmed in a large group of IUGR and control samples, the up-regulated factors leptin, IGFBP-1, and CRH may serve as candidate genes for the prediction of subsequent metabolic consequences in IUGR newborns. These three factors may not only influence growth of the foetus, but might also interact with programming of its metabolic functions, which has to be determined in an ongoing study.

A MONTE CARLO STUDY OF SIMULATED MEASUREMENTS OF RADIONUCLIDES IN BONE.

When measuring the internally deposited activity in the bone of a subject, the placement of the detector is critical. This study reports the simulated counting efficiencies for three counting geometries, the skull, knee and shin, using 13 different voxel phantoms. It shows that the range of counting efficiencies for a given geometry is large for the studied phantoms, especially at low energies. Skull counting offers higher efficiency for low energies such as the 17 keV compared to knee counting or shin counting, but this advantage disappears when the energy is higher such as at 185 keV. This work also shows that the calibration phantom may greatly impact the accuracy of the activity estimate in bone counting, with uncertainties increasing greatly as the photon energy is reduced. Estimating the activity of a radionuclide in bone from direct counting has large uncertainties, and the dose calculated from a skeleton measurement would need careful analysis and, if possible, supporting data from other bioassay measurements.

The effect of lung deposition patterns on the activity estimate obtained from a large area germanium detector lung counter.

Lung counters for in vivo detection of low energy photon emitters are typically calibrated using phantoms containing lung tissue equivalent material with the radioactivity homogeneously distributed throughout the material. If the activity in a measurement subject is heterogeneously distributed, the activity estimate for that subject will be uncertain due to the assumptions of distribution. The magnitude of the uncertainty for a four-detector germanium array, using the Lawrence Livermore National Laboratory torso phantom with a newly designed lung set that allows the activity to be localized in one or more of 16 areas, was estimated. The results show that detector arrays will reduce the uncertainties arising from the geometry of the lung deposition compared to single detectors. The estimated activity of an internal deposition that emits 17.5 keV photons can be overestimated by a factor of three, or underestimated by a factor of infinity (i.e., the activity is missed completely). As the photon energy rises to 59.5 keV the uncertainty in the activity decreases so that the maximum overestimate (underestimate) will be a factor of two (five). As the energy rises to 344.3 keV only the maximum underestimate changes: it becomes a factor of three.

Comparison of the LLNL and JAERI torso phantoms using Ge detectors and phoswich detectors.

The Human Monitoring Laboratory has compared the LLNL and JAERI torso phantoms using its germanium detector lung counting system by measuring the counting efficiencies for radioactive materials in the phantoms at photon energies of 17.7 keV, 59.5 keV, 121.8 keV, and 344 keV to assess the similarity (or differences) in performance characteristics. The counting efficiencies obtained from the two phantoms were compared by converting the Chest Wall Thickness data and Adipose Mass Fractions of the phantoms to Muscle Equivalent Chest Wall Thicknesses. The counting efficiencies for the two phantoms were found to be within a factor of 1.44 of each other at 17.7 keV, 1.30 at 59.5 keV, 1.25 at 121.8 keV, and 1.17 at 344 keV when using a four detector array (JAERI efficiency divided by LLNL efficiency). However, individual detector responses show that the counting efficiencies from the two phantoms differ considerably in the region of the heart (up to a factor of 6 at 17 keV). Other areas above the lungs give counting efficiencies that are similar to each other. A routine intercomparison exercise with Cameco Corporation has shown that the counting efficiencies derived from the LLNL and JAERI phantoms were found to be within a factor of 1.18 (JAERI/LLNL) when a natural uranium lung set was used to calibrate a lung counter consisting of phoswich detectors. This work has also shown that over the energy range 63 keV-185 keV the LLNL phantom can be used to calibrate phoswich detector systems that are positioned on the back of the subject.

Chest wall thickness measurements and the dosimetric implications for male workers in the uranium industry.

The Human Monitoring Laboratory has measured the chest wall thickness and adipose mass fraction of a group of workers at a Canadian uranium refinery, a conversion plant, and a fuel fabrication site using ultrasound. A site-specific biometric equation has been developed for these workers, who seem to be somewhat larger than other workers reported in the literature. Chest wall thickness is a very important modifier on lung counting efficiency and these data have been put into the perspective of the impending Canadian dose limits that will reduce the limit of occupationally exposed workers to 100 mSv in a 5-y period with a maximum of 50 mSv in any one year. The sensitivity of the germanium and phoswich based lung counting systems have been compared. Over a range of chest wall thickness of 1.6 cm to 6.0 cm and using a 30-min counting time, the achievable MDA's lie in the range of 6.7 mg to 19.1 mg or 6.7 mg to 30 mg with a two-phoswich-detector array or a germanium lung counting system, respectively. Depending on chest wall thickness, these achievable MDA's are close to, or exceed, the predicted amounts of natural uranium that will remain in the lung (absorption type M and S) after an intake equivalent to the Annual Limit on Intake that corresponds to 20 mSv. Neither system is sufficiently sensitive to detect an intake of Type S natural uranium in a worker with a chest wall thickness that corresponds to the average (3.73 cm) if it occurred more than 7 d prior to the lung count.

Comparison of sliced and whole lung sets for the LLNL and JAERI torso phantoms using GE detectors.

The performance characteristics of sliced lung sets were compared to lung sets with activity homogeneously distributed throughout the lung tissue substitute material. The activity estimate from planar sources differs from the estimate from homogeneous sources by a factor of 0.88 to 1.09 depending on the photon energy. This error is small compared to other uncertainties commonly encountered in lung counting, i.e., activity deposition in the lung, detector placement, size difference between individuals, etc. Sliced lung sets could be used instead of homogeneous lung sets to test or provide an interim calibration for a lung counting system.

Comparison of the ANSI, RSD, KKH, and BRMD thyroid-neck phantoms for 125I thyroid monitoring.

The Human Monitoring Laboratory, which acts as the Canadian National Calibration Reference Centre for In Vivo Monitoring, has determined the performance characteristics of four thyroid phantoms for 125I thyroid monitoring. The phantoms were a phantom built to the specifications of the American National Standards Institute Standard N44.3; the phantom available from Radiology Support Devices; the phantom available from Kyoto Kagaku Hyohon; the phantom manufactured by the Human Monitoring Laboratory and known as the BRMD phantom. The counting efficiencies of the phantoms for 125I were measured at different phantom-to-detector distances. The anthropomorphic characteristics of the phantoms have been compared with the average man parameters. It was concluded that the BRMD, American National Standards Institute, and Radiology Support Devices phantoms have the same performance characteristics when the neck-to-detector distances are greater than 12 cm and all phantoms are essentially equivalent at 30 cm or more. The Kyoto Kagaku Hyohon phantom showed lower counting efficiencies at phantom-to-detector distances less than 30 cm. This was attributed to the design of the phantom. This study has also shown that the phantom need not be highly anthropomorphic provided the calibration is not performed at short neck-detector distances. Indeed, it might be possible to use t simple point source of 125I placed behind a 1.5 cm block of lucite at neck detector distances of 12 cm or more.

Comparison of two JAERI phantoms and the problems discovered.

During the course of an intercomparison exercise it was possible to compare two JAERI phantoms with each other by using a multi-energy photon emitting lung set (241Am/152Eu). One belonged to the IAEA (Vienna), the other belonged to the Human Monitoring Laboratory (Ottawa). The intercomparison of the phantoms showed that they were statistically distinct from each other, although the differences were small. The counting efficiencies varied from each other by about 4% at 17 keV and 2% at photon energies above 17 keV. It was concluded that these difference were either due to small variations of chest wall thickness during the manufacturing process or positioning errors. The intercomparison also revealed a serious problem with one of the overlay plates of the HML's phantom. The adipose mass fraction of the overlay plate was found to be much greater (approximately 40%) than the manufacturer's stated value (10%).

Comparison of the 1st, 2nd and 3rd generation Lawrence Livermore National Laboratory Torso phantoms.

The Lawrence Livermore National Laboratory (LLNL) Torso phantom, which is the de facto standard for lung counter calibration for low energy photon emitters, has undergone a number of revisions since its development. The first generation used real human bone: the second generation used synthetic bone and had a major design change; the third generation had more subtle material and mould changes. This work has compared a first generation, two second generation, and two third generation LLNL phantoms to see if there are any differences between the phantoms. The comparison of five LLNL phantoms using the same counting regions has shown that the second and third generation phantoms are essentially equivalent at low photon energies, but the first generation phantom shows an increased counting efficiency at low photon energies due to a design flaw. It is also apparent that these phantoms have maintained their performance characteristics over an extended period of time.

Biological half-life of iodine in adults with intact thyroid function and in athyreotic persons.

A joint project between the Human Monitoring Laboratory (HML) and the Ottawa Hospital has measured the retention of 131I in patients who have received the radioiodine diagnostically. Thirty-nine subjects with intact thyroid glands and nine athyreotic subjects were measured in the HML's whole-body/thyroid counter to determine the retention of 131I following its medical administration. The average biological half-life of 131I in 26 euthyroid subjects was found to be 66.1+/-6.3 days which may he statistically significantly lower than the ICRP recommended value of 80 days. Nine hyperthyroid patients had a mean biological half-life of 38.2+/-8.6 days and in three hypothyroid patients the corresponding value was 29.3+/-8.8 days. Thyroid 131I uptake was measured in a conventional clinical fashion at the Ottawa Hospital Civic campus 24 h after oral administration of the radioiodine using a collimated thick sodium iodide detector placed over the neck anteriorly. Measured values were 10.144+/-0.009, 0.314+/-0.035 and 0.045+/-0.010 of the administered dose in euthyroid, hyperthyroid and hypothyroid patients respectively. The euthyroid range at the hospital is 0.06 - 0.22. Uptake was significantly lower for the euthyroid group than the ICRP value of 0.3. The radioiodine retention in athyreotic subjects followed a two compartment model with biological half-lives of 1.0+/-1.2 days and 18.4+/-1.1 days.

Accurate and reproducible ion mobility measurements for chemical standard evaluation.

Chemical standards are used to calibrate ion mobility spectrometers (IMS) for accurate and precise identification of target compounds. Research over the past 30 years has identified several positive and negative mode compounds that have been used as IMS standards. However, the IMS research community has not come to a consensus on any chemical compound(s) for use as a reference standard. Also, the reported K(0) values for the same compound analyzed on several IMS systems can be inconsistent. In many cases, mobility has not been correlated with a mass identification of an ion. The primary goal of this work was to provide mass-identified mobility (K(0)) values for standards. The results of this work were mass-identified K(0) values for positive and negative mode IMS chemical standards. The negative mode results of this study showed that TNT is a viable negative mode reference standard. New temperature-dependent K(0) values were found by characterizing drift gas temperature and water content; several examples were found of temperature-dependent changes for the ion species of several standards. The overall recommendation of this study is that proposed IMS standards should have temperature-dependent K(0) values quoted in the literature instead of using a single K(0) value for a compound.

Functional analysis of an eye specific enhancer of the eyeless gene in Drosophila.

The development of the Drosophila compound eye requires the function of a set of evolutionarily conserved genes. Among these, the Drosophila Pax-6 gene eyeless (ey) plays a major role. ey has been considered a master control gene of eye development in the animal kingdom because targeted expression of ey and vertebrate as well as invertebrate homologs lead to the formation of ectopic eyes in Drosophila. We demonstrate that an intron of the ey gene contains an enhancer that regulates the eye specific expression of the gene in the eye disc primordia of embryos and in the eye imaginal discs of third instar larvae. Moreover, a 212-bp enhancer element is necessary and sufficient for the enhancer function. It is partially conserved in Drosophila hydei and contains putative Pax-6 Paired domain binding sites. We show that several binding sites are required for the eye specific expression, and, therefore, we propose a Pax-6-like molecule to be a positive transactivator for the eye specific ey expression. This transactivator recently has been identified as twin of eyeless, the second Pax-6 gene in Drosophila.

[Blood pressure values in normal pregnancy]. / Blutdruckverhalten in der normalen Schwangerschaft.

In two studies independent from each other we examined the behaviour of arterial blood pressure in normal pregnancy. Study 1 was performed in exactly defined external conditions, study 2 in normal antenatal clinic. Especially in study 1 a distinct reduction of blood pressure could be proved. Towards the end of pregnancy there is a raise of blood pressure. Blood pressure is dependent on the position of the body. Havdarized examination conditions have to be claimed with respect to reproducibility and comparability of the values.