Field Angle Tuned Metamagnetism and Lifschitz Transitions in UPt3.

Strongly correlated electronic systems can harbor a rich variety of quantum spin states. Understanding and controlling such spin states in quantum materials is of great current interest. Focusing on the simple binary system UPt3 with ultrasound (US) as a probe we identify clear signatures in field sweeps demarkating new high field spin phases. Magnetostriction (MS) measurements performed up to 65 T also show signatures at the same fields confirming these phase transitions. At the very lowest temperatures (<200 mK) we also observe magneto-acoustic quantum oscillations which for θ = 90° (B||c-axis) and vicinity abruptly become very strong in the 24.8-30 T range. High resolution magnetization measurements for this same angle reveal a continuous variation of the magnetization implying the subtle nature of the implied transitions. With B rotated away from the c-axis, the US signatures occur at nearly the same field. These transitions merge with the separate sequence of the well known metamagnetic transition which commences at 20 T for θ = 0° but moves to higher fields as 1/cosθ. This merge, suggesting a tricritical behavior, occurs at θ ≈ 51° from the ab-plane. This is an unique off-symmetry angle where the length change along the c-axis is precisely zero due to the anisotropic nature of MS in UPt3 for all magnetic field values.

The potential application of biosurfactant produced by Pseudomonas aeruginosa TGC01 using crude glycerol on the enzymatic hydrolysis of lignocellulosic material.

The production of biosurfactant by Pseudomonas aeruginosa TGC01 using crude glycerol and sodium nitrate as the sole substrate and nitrogen source, respectively, was investigated using two mineral culture media. Two inoculum sizes (5 and 10% v/v) and two volumes of the culture medium (50 and 100 mL) in 500 mL Erlenmeyer flask also were used. Enzymatic hydrolyses of waste office paper (WOP), newspaper (NP) and eucalyptus wood chips (EWC) were carried out using the biosurfactant from P. aeruginosa TGC01. The decrease in volume of the culture medium increased the production of rhamnolipid by 500% in relation to concentration obtained when higher volume of culture medium was used. High quantity biosurfactant was recovered (11 g/L) with desired surface active properties after extraction using chloroform:methanol (v/v). The biosurfactant was able to reduce the water surface tension from 72 to 27 mN/m with a critical micelle concentration (CMC) of 100 mg/L and a stable emulsion index (above 60%) in the enzymatic hydrolysis (pH 4.8 and 50 °C for 4 h). Biosurfactant increased the glucose released in the enzymatic hydrolysis in relation to control (without tensoactive) when WOP (19% increase) and NP (113% increase) were used. The process for NP (18% lignin) was economical, given that the biosurfactant present made a delignification process unnecessary.

[Fostering of health economics in Germany]. / Entwicklung der Gesundheitsökonomie in Deutschland.

Health economics is now well established in Germany with the aim to apply economic tools to answer problems in health and health care. After a short review of the international development of health economics and the development in Germany in particular, the article looks at selected recent topics of health economic analysis in Germany (economic evaluation, industrial economics, health and education).

Seroprevalence of Neospora caninum and Toxoplasma gondii antibodies in white-tailed deer (Odocoileus virginianus) from Iowa and Minnesota using four serologic tests.

The white-tailed deer (Odocoileus virginianus) is considered one of the most important wildlife reservoirs of Neospora caninum and Toxoplasma gondii in the US. Sera from white-tailed deer from Minnesota and Iowa were tested for antibodies to N. caninum by four serologic tests including the indirect fluorescent antibody (IFA) test (cut-off 1:25), Neospora caninum agglutination test (cut-off 1:25), an enzyme-linked immunoabsorbent assay, and Western blot (WB). Sera were also tested for antibodies to T. gondii using the modified agglutination test (cut-off 1:25). Of 62 adult deer from Minnesota antibodies to T. gondii were found in 20 (32.2%), N. caninum in 44 (71%), with dual infections in 18 deer. Of 170 (73 fawns, 9 yearlings, 88 adults) deer from Iowa, T. gondii antibodies were present in 91 (53.5%) with 37.0, 55.6 and 67.0% seropositivity in fawns, yearlings, and adults, respectively. Antibodies to N. caninum were found in 150 of 170 (88.2%) by any of the 3 tests (99 by Western blots, 135 by ELISA, 106 by IFA, and 118 by NAT). Dual infections with T. gondii and N. caninum were detected in 47 deer. Very high (84.9%) seropositivity of N. caninum in fawns suggests high rate of congenital transmission of the parasite. Seropositivity in each test at different titers is discussed.

Separating the vibrationally resolved Auger decay channels for a CO core hole state.

The K-VV Auger spectrum of carbon monoxide (CO) excited by C 1s photoionization has been investigated with a novel electron-electron coincidence setup. The energy resolution is sufficiently high to resolve the vibrational energy levels of the core-ionized intermediate state and of most dicationic final states in the two-dimensional electron energy map. We demonstrate how the influence of vibrational states on a molecular Auger spectrum can be accessed experimentally without the constraint of averaging over all intermediate state energies.

Transplacental toxoplasmosis in naturally-infected white-tailed deer: Isolation and genetic characterisation of Toxoplasma gondii from foetuses of different gestational ages.

Clinical toxoplasmosis is most severe in congenitally-infected hosts. In humans, transmission of Toxoplasma gondii from the mother to the foetus is considered to be most efficient during the last trimester of pregnancy but clinical congenital toxoplasmosis is more severe if transmission occurs during the first trimester. However, there are no data on the rate of congenital transmission of T. gondii with respect to gestational age in any host during natural infection. In the present study, attempts were made to isolate T. gondii by bioassay in mice inoculated with tissues from foetuses of 88 naturally-exposed white-tailed deer from Iowa and Minnesota. Viable T. gondii was isolated from foetuses of six of 61 deer in early pregnancy (45-85 days of gestation) from Iowa and foetuses of nine of 27 deer from Minnesota in mid-gestation (130-150 days) of a gestational period of 7 months. The 15 T. gondii isolates obtained from foetal deer were PCR-restriction fragment length polymorphism genotyped using polymorphisms at 10 nuclear markers including SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and an apicoplast marker, Apico. Five genotypes were revealed, including the clonal Type II and III lineages, and three non-clonal genotypes. DNA sequencing analysis of representative isolates at loci SAG2, c22-8, L358 and PK1 revealed that the three non-clonal genotypes are closely related to the clonal Type I, II and III lineages. It is very likely that these non-clonal genotypes were derived from genetic crosses among the three clonal Type I, II and III lineages. The most common genotype was Type II, commonly found in humans in North America and Europe, suggesting the possible link of transmission from game animals to humans.

Pre- and postnatal imaging of a girl with a cloacal variant.

We describe the prenatal MR findings in a 29-week fetus with a cloacal variant (urogenital sinus and anterior placed anus) in combination with an enlarged clitoris and urethral duplication and correlate them with postnatal imaging. Fetal MR imaging permits the diagnosis and characterization of cloacal and urogenital sinus malformations in utero. This information may guide pre-, peri- and postnatal management.

A fetal sheep liver extract containing immunostimulatory substances including LPS acts as leukocyte activator in cells of LPS responder and non responder mice.

Purified fractions from a fetal sheep liver extract (FSLE) were investigated, in a murine model, for induction of leukocyte stimulating activities. The fractions FSLE-1 and FSLE-2 induced splenocyte proliferation in vitro in C57Bl/10ScSn (LPS responder) mice comparable to LPS, and in C57Bl/10ScCr (LPS non responder) mice. They also stimulated the release of nitrogen radicals in bone marrow-derived macrophages (BMDM) from several mouse inbred strains including both C57Bl/10ScSn and C57Bl/10ScCr mice. Stimulation of NO production could be blocked by L-NMMA, an inhibitor of iNOS, and enhanced by the simultaneous addition of IFN-gamma. Moreover, stimulation of macrophages by FSLE-1 and FSLE-2 induced a cytostatic effect of the activated macrophages for Abelson 8-1 tumor cells. The stimulatory activity of the purified fractions is partially due to trace amounts of LPS derived from the fetal liver extract which was enriched during purification. Our results may help to explain the beneficial effect of the extract in patients which has been observed clinically.

Observation of resonant interatomic coulombic decay in Ne clusters.

We have measured the electron spectra of Ne clusters after excitation with photon energies around the 2s inner valence threshold. At two photon energies below threshold, a resonantly enhanced surplus of low kinetic-energy electrons is observed. The kinetic energy of the peak does not vary with the photon energy and is slightly larger than the transition energy of Interatomic Coulombic Decay (ICD) above threshold. This leads us to assume that an ICD-like process is present. In analogy to the Auger and the resonant Auger decay this new phenomenon is termed resonant ICD.

Solitary infantile choriocarcinoma of the liver: MRI findings.

Infantile hepatic choriocarcinoma is a rare, highly malignant germ-cell tumour believed to result from a choriocarcinoma of the placenta that spreads to the child. Most infants present with a characteristic clinical picture of anaemia, hepatomegaly and precocious puberty. Imaging findings, including conventional MRI, may be non-specific. To improve the accuracy of diagnosis, we present the imaging findings of contrast-enhanced dynamic MRI in a 4.5-month-old boy with infantile hepatic choriocarcinoma.

Radiographic and MRI features of deferiprone-related arthropathy of the knees in patients with beta-thalassemia.

OBJECTIVE: This study was undertaken to describe the radiographic and MRI appearances of arthropathy of the knees in 14 patients with beta-thalassemia major undergoing chelation therapy with deferiprone (L1). MATERIALS AND METHODS: All available radiographs and MRI studies of the knees in 14 beta-thalassemia major patients (mean age, 16.3 years; age range, 7-33 years) undergoing chelation therapy with L1 were retrospectively assessed for changes in the synovium, cartilage, and bone. Imaging findings and signs of knee arthropathy were correlated with chelation therapy and average serum ferritin concentration. RESULTS: Nine (64%) of the 14 patients developed arthralgia of the knees during treatment with L1. Abnormal imaging findings were present in all symptomatic and two asymptomatic patients (12/14, 86%) and included joint effusion, subchondral bone irregularity, and patellar beaks. Additional MRI findings were thickening and enhancement of the synovium; hypointense bands in the synovium; irregularly thickened epiphyseal and articular cartilage overlying subchondral bone defects; and, on T2-weighted sequences, hyperintense articular cartilage lesions. The degree of knee symptoms at the time of imaging did not reflect the severity of cartilage and subchondral bone changes. CONCLUSION: Radiologic changes can be seen in L1-related arthropathy and should be recognized. MRI of the knees should be considered in symptomatic children and young adults with thalassemia undergoing L1 chelation therapy for iron overload.

Triacyl-lipopentapeptide adjuvants: TLR2-dependent activation of macrophages and modulation of receptor-mediated cell activation by altering acyl-moieties.

Synthetic lipopeptides derived from bacterial lipoprotein are efficient immunoadjuvants. In vitro they activate antigen presenting cells (APCs) to induce the translocation of nuclear factor kappa B (NF-kappaB) and the activation of further transcription factors. This results in the expression of genes encoding cytokines such as IL-1, IL-6, TNF-alpha and in the release of reactive oxygen/nitrogen intermediates. The molecular structure of microbial products determines TLR specificity and thus their activatory potential and immunoadjuvanticity. In the present study, we investigated the lipopeptide-induced activation of leukocytes at different cellular levels by applying derivatives of a synthetic lipopentapeptide-fatty acid library. Our results show that TLR2 plays a key role for the activation of bone marrow-derived macrophages (BMDMs) by lipopentapeptide derivatives and that the fatty acid composition of the lipopeptides determines their activation potential and TLR specificity.

Probability of cortical infarction predicted by flumazenil binding and diffusion-weighted imaging signal intensity: a comparative positron emission tomography/magnetic resonance imaging study in early ischemic stroke.

BACKGROUND AND PURPOSE: The differentiation of reversible from irreversible ischemic damage is essential for identifying patients with acute ischemic deficits who may benefit from therapeutic interventions. Diffusion-weighted imaging (DWI) has become the method of choice to detect ischemic lesions. Positron emission tomography (PET) of the central benzodiazepine receptor ligand 11C flumazenil (FMZ) has been shown to be a reliable marker of neuronal integrity. These 2 imaging parameters were compared with respect to the probability to predict cortical infarction in early ischemic stroke. METHODS: In 12 patients with acute stroke, results from DWI (median, 6.5 hours after symptom onset) and FMZ-PET (interval, 85 minutes between DWI and PET) were compared with infarct extension 24 to 48 hours after onset of stroke on T2-weighted magnetic resonance imaging (T2-MRI). Probability curves predictive of eventual infarction were computed using respective DWI, FMZ, and apparent diffusion coefficient (ADC) values for voxels of interest (VOI) later classified as representing infarcted or noninfarcted tissue. RESULTS: Ninety-five percent limits predictive of cortical infarction were determined for relative FMZ binding (< or =3.2), DWI signal intensity (> or =1.18), and ADC values (< or =0.83). Cortical regions with values beyond these 95% limits did not necessarily overlap with nor were fully congruous with final cortical infarct volumes. The respective median volumes for these regions were FMZ median 10.9, range 0 to 99.7 cm3; DWI median 15.2, range 0 to 116.0 cm3; ADC median 12.4, range 0 to 112.7 cm3; and final infarct median 14.9, range 0 to 114.7 cm(3). Overall, 83.5% of the final infarct, on average, was predicted by decreased FMZ binding, 84.7% by increased DWI signal intensity, and 70.9% by a decreased ADC value. The portions of the final infarct not predicted in the early investigation (false-negatives) were 4.8 cm3 (median) for FMZ, 3.7 cm3 for DWI, and 6.0 cm3 for ADC. The false-positive volumes not included in the final infarct were 0 cm3 (median) for FMZ, 5.1 cm3 for DWI, and 3.6 cm3 for ADC. CONCLUSIONS: These results indicate that FMZ-PET and DWI are comparable in the prediction of probability of ischemic cortical infarction, but FMZ-PET carries a lower probability of false-positive prediction. The final infarcts include tissue not identified by these imaging modalities; at the time of the study, these tissue compartments are viable and could benefit from treatment. The discrepancy in predictive probability could be related to the fundamental difference of the measured variables: benzodiazepine receptor activity is a reliable marker of neuronal integrity in the cortex, and movement of water molecules in the extracellular space might be a more variable indicator of tissue damage.

Renal dimensions measured by ultrasonography in children: variations as a function of the imaging plane and patient position.

The purpose of this study was to determine the effect of patient positioning on sonographic renal measurements and to test if the patient position alters the three-dimensional shape of the kidneys. The maximum longitudinal renal length and transverse renal width and depth were measured in the supine and prone position in 100 children (200 kidneys). Age ranged from 6 months to 16 years (mean age 5 years). The results were compared for statistically significant differences. The maximum measured longitudinal renal length was statistically significantly larger in the supine than in the prone position (supine position, left: 8.0 cm; right: 7.7 cm; prone position, left: 7.9 cm, right: 7.6 cm; P<0.001). There was no statistically significant change in the transverse diameters (width and depth, P>0.001) and renal volume ( P>0.001) in the supine vs. prone positions. Our results show that position-induced reshaping of the kidneys is unlikely to be responsible for the discrepancy in maximum longitudinal renal measurements comparing supine with prone positions. Position-dependent changes in the degree of filling of the renal calyces and pelvis as well as errors in caliper distance measurements for the different scan depths (supine vs. prone) are more likely to be responsible for the encountered differences. Consequently, we recommend to add prone renal length measurements in addition to the supine measurements. In follow-up examinations, renal length measurements should only be compared that have been collected in the same patient position.

Developmental nasal midline masses in children: neuroradiological evaluation.

Developmental nasal midline masses in children are rare lesions. Neuroimaging is essential to characterise these lesions, to determine the exact location of the lesion and most importantly to exclude a possible intracranial extension or connection. Our objective was to evaluate CT and MRI in the diagnosis of developmental nasal midline masses. Eleven patients (mean age 4.5 years) with nasal midline masses were examined by CT and MRI. Neuroimaging was evaluated for (a) lesion location/size, (b) indirect (bifid or deformed crista galli, widened foramen caecum, defect of the cribriform plate) and direct (identification of intracranially located lesion components or signal alterations) imaging signs of intracranial extension, (c) secondary complications and (d) associated malformations. Surgical and histological findings served as gold standard. Nasal dermoid sinus cysts were diagnosed in 9 patients. One patient was diagnosed with an meningocele and another patient with a nasal glioma. Indirect CT and MRI signs correlated with the surgical results in 10 of 11 patients. Direct CT findings correlated with surgery in all patients, whereas the direct MRI signs correlated in 9 of 11 patients. In 2 patients MRI showed an intracranial signal alteration not seen on CT. Neuroimaging corrected the clinical diagnosis in 1 patient. One child presented with a meningitis. In none of the patients was an associated malformation diagnosed. Intracranial extension is equally well detected by CT and MRI using indirect imaging signs. Evaluating the direct imaging signs, MRI suspected intracranial components in 2 patients without a correlate on CT. This could represent an isolated intracranial component that got undetected on CT and surgery. In 9 patients CT and MRI matched the surgical findings. The MRI did not show any false-negative results. These results in combination with the multiplanar MRI capabilities, the different image contrasts that can be generated by MRI and the lack of radiation favour the use of MRI as primary imaging tool in these young patients in which the region of imaging is usually centred on the radiosensitive eye lenses.

Burkitt's lymphoma with bilateral cavernous sinus and mediastinal involvement in a child.

We report a 12-year-old boy who presented with incomplete right ophthalmoplegia, exophthalmos and headache. Initial CT and MRI revealed a mass in the right cavernous sinus. During tumour work-up, CT identified additional tumour within the mediastinum. Biopsy of the mediastinal lesion identified Burkitt's lymphoma. We report on this case because radiologists and clinicians should be alerted to identify sites of primary Burkitt's lymphoma outside of the central nervous system if clinical symptoms indicate, or imaging shows, CNS lesions. Primary CNS involvement in Burkitt's lymphoma is rare.

Is the genetic liability in multifactorial disorders higher in concordant than discordant monozygotic twin pairs? A population-based family twin study of migraine without aura.

Migraine without aura (MO) is a multifactorial disorder. Expression of a disorder with multifactorial inheritance depends on the genetic liability and on environmental factors. A high liability is reflected by a high frequency of affected relatives. We have previously shown that monozygotic (MZ) twin pairs have a significant higher concordance of MO than dizygotic twin pairs. The incomplete concordance among MZ twin pairs may be due to a lower genetic liability among discordant than concordant MZ twin pairs. The present study analysed the genetic liability in MZ twin pairs concordant and discordant for MO by the population-relative risk of MO among parents and siblings. The twin pairs were from the population-based Danish Twin Register. First-degree relatives of 29 concordant and 34 discordant MZ twin pairs were blindly telephone interviewed by a physician. The participation rate of the eligible first-degree relatives was 96%. The population-relative risk of MO among parents and siblings was 2.73 (2.39-3.06) in concordant and 2.37 (2.03-2.71) in discordant MZ twin pairs. The relative risk of MO was significantly higher in female first-degree relatives of concordant than of discordant MZ male and female twin pairs. An opposite effect was observed in male first-degree relatives, although this was not significant for male first-degree relatives of female MZ twin pairs. The present study found no statistically significant difference in genetic liability to MO among concordant and discordant MZ twin pairs. However, a difference in genetic liability among MZ and DZ twin pairs is anticipated to be small. Thus, it may be possible to show the effect in a larger study population or by investigating a more frequent trait than MO.

[The significance of genetic and environmental factors for migraine with aura. A genetic epidemiologic study of Danish twins]. / Betydningen af arv og miljø for migraene med aura. En genetisk epidemiologisk undersøgelse af danske tvillingpar.

We studied the genetic and environmental influence on migraine with aura (MA) by analysing a twin population. The twin sample consisted of 2,026 monozygotic (MZ) pairs and 3,334 same-gender dizygotic (DZ) pairs recruited from the population-based Danish Twin Register. A total of 211 pairs were identified, of whom 77 were MZ and 134 were DZ. The pairwise concordance rate was significantly higher in MZ-than in DZ-pairs, i.e. 34% and 12%, respectively, emphasizing the importance of genetic factors in MA. However, environmental factors are also important, as the pair wise concordance rate was less than 100% in MZ-pairs. Similarly, the recurrence risk of MA was 50% in MZ- and 21% in DZ-pairs which was a significant difference. In non-twin siblings, the recurrence risk of MA is 27%, which is similar to the recurrence risk in DZ-pairs. This indicates that MA is not developed due to specific environmental factors shared by the twins.

Possible risk factors and precipitants for migraine with aura in discordant twin-pairs: a population-based study.

The aim of the present study was to detect possible risk factors in migraine with aura (MA) by analysis of discordant twin-pairs. In a recent population-based twin study we established that environmental factors account for approximately 50% of the variation in liability to MA. A cohort of 5,360 same-gender twin-pairs from the general population was screened for migraine. All twin-pairs with possible migraine were interviewed by a physician. A questionnaire provided information about living conditions and lifestyle. Of the 169 discordant twin-pairs 51 were monozygotic and 118 were dizygotic twin-pairs. Several putative risk factors-schooling, education, marital status, smoking status and alcohol consumption-showed no association with MA. The presence of migraine without aura or tension-type headache did not increase the risk of MA. Stress and mental tension, and bright light precipitated attacks of MA in, respectively, 44% and 28% of the twins.

Glyceryl trinitrate induces attacks of migraine without aura in sufferers of migraine with aura.

Migraine with aura and migraine without aura have the same pain phase, thus indicating that migraine with aura and migraine without aura share a common pathway of nociception. In recent years, increasing evidence has suggested that the messenger molecule nitric oxide (NO) is involved in pain mechanisms of migraine without aura. In order to clarify whether the same is true for migraine with aura, in the present study we examined the headache response to intravenous infusion of glyceryl trinitrate (GTN) (0.5 microg/kg/min for 20 min) in 12 sufferers of migraine with aura. The specific aim was to elucidate whether an aura and/or an attack of migraine without aura could be induced. Fourteen healthy subjects served as controls. Aura symptoms were not elicited in any subject. Headache was more severe in migraineurs than in the controls during and immediately after GTN infusion (p=0.037) as well as during the following 11 h (p = 0.008). In the controls, the GTN-induced headache gradually disappeared, whereas in migraineurs peak headache intensity occurred at a mean time of 240 min post-infusion. At this time the induced headache in 6 of 12 migraineurs fulfilled the diagnostic criteria for migraine without aura of the International Headache Society. The results therefore suggest that NO is involved in the pain mechanisms of migraine with aura. Since cortical spreading depression has been shown to liberate NO in animals, this finding may help our understanding of the coupling between cortical spreading depression and headache in migraine with aura.