Evidence for extinct Cs-135 from Ba isotopes in Allende CAIs?

he abundance and distribution of isotopes throughout the Solar System can be used to constrain the number and type of nucleosynthetic events that contributed material to the early nebula. Barium is particularly well suited to quantifying the degree of isotope heterogeneity in the Solar System because it comprises seven stable isotopes that were synthesized by three different nucleosynthetic processes (s-, r-, and p-processes), all of which contributed material to the Solar System. There is also potential contribution to 135Ba from short-lived radioisotope 135Cs, conclusive evidence for which is yet to be reported. Four Allende (CV3) Ca,Al-rich inclusions (CAI 1, CAI 2, CAI 4, CAI 5) and one Allende dark inclusion (DI) were analyzed for Ba isotope variability. Two CAIs (CAI 2 and CAI 5) display 135Ba excesses that are not accompanied by 137Ba anomalies. Calcium–aluminum-rich inclusion 1 displays a 135Ba excess that is possibly coupled with a 137Ba excess, and the remaining refractory inclusions (CAI 2 and DI) have terrestrial Ba isotope compositions. These Ba isotope data are presented in conjunction with published whole rock Ba isotope data from individual Allende CAIs. The enrichment in 135Ba and absence of coupled 137Ba excesses in CAI 2 and CAI 5 is interpreted to indicate that the anomalies are not purely nucleosynthetic in origin but also contain contributions (16–48 ppm) from the decay of short-lived 135Cs. The majority of Allende CAIs studied to date may also have similar contributions from 135Cs on the basis of higher than expected 135Ba excesses if the Ba isotope anomalies were purely nucleosynthetic in origin. The 135Ba anomalies appear not to be coupled with superchondritic Cs/Ba, which may imply that the contribution to 135Ba did not occur via in situ decay of live 135Cs. However, it is feasible that the CAIs had a superchondritic Cs/Ba during decay of 135Cs, but Cs was subsequently removed from the system during aqueous alteration on the parent body. An alternative scenario is the potential existence of a transient high-temperature reservoir having superchondritic Cs/Ba in the early Solar System while 135Cs was extant, which enabled a radiogenic 135Ba signature to develop in some early condensates. The nucleosynthetic source of 135Cs can be determined by reconciling the predicted astrophysical 135Cs abundance with its measured abundance in meteorites. Further, the currently accepted initial 135Cs/133Cs of the Solar System, [135Cs/133Cs]0, may be underestimated because the spread of Cs/Ba among samples is small and the range of excess 135Ba is limited thus leading to inaccuracies when estimating [135Cs/133Cs]0. If the initial meteoritic abundance of 135Cs was indeed higher than is currently thought, the most probable stellar source of short-lived radioisotopes was a nearby core-collapse supernova and/or the Wolf–Rayet wind driven by its progenitor.

Does a pleiotropic gene explain deafness and blue irises in white cats?

The prevalence of deafness is high in cat populations in which the dominant white gene is segregating. The objective of this study was to investigate whether there is a gene that is responsible for deafness as well as for blue eyes and to establish a plausible mode of inheritance. For this purpose, data from an experimental colony with deaf cats were analyzed. The hearing status was determined by acoustically evoked brain stem responses (BAER). Complex segregation analyses were conducted to find out the most probable mode of inheritance using maximum likelihood procedures. The prevalence of deafness and partial hearing in the experimental colony was 67% and 29%, respectively. The results of the bivariate segregation analysis support the hypothesis of a pleiotropic major gene segregating for deafness and blue iris colour. The high heritability coefficients for both traits, 0.55 and 0.75 respectively, indicate that beside the major gene there is an important influence of polygenic effects.

Experimental folate and vitamin B12 deficiency does not alter bone quality in rats

Hyperhomocysteinemia (HHCY) has been linked to fragility fractures and osteoporosis. Folate and vitamin B(12) deficiencies are among the main causes of HHCY. However, the impact of these vitamins on bone health has been poorly studied. This study analyzed the effect of folate and vitamin B(12) deficiency on bone in rats. We used two groups of rats: a control group (Co, n = 10) and a vitamin-deficient group (VitDef, n = 10). VitDef animals were fed for 12 wk with a folate- and vitamin B(12)-free diet. Co animals received an equicaloric control diet. Tissue and plasma concentrations of homocysteine (HCY), S-adenosyl-homocysteine (SAH), and S-adenosyl-methionine (SAM) were measured. Bone quality was assessed by biomechanical testing (maximum force of an axial compression test; F(max)), histomorphometry (bone area/total area; B.Ar./T.Ar.], and the measurement of biochemical bone turnover markers (osteocalcin, collagen I C-terminal cross-laps [CTX]). VitDef animals developed significant HHCY (Co versus VitDef: 6.8 +/- 2.7 versus 61.1 +/- 12.8 microM, p < 0.001) that was accompanied by a high plasma concentration of SAH (Co versus VitDef: 24.1 +/- 5.9 versus 86.4 +/- 44.3 nM, p < 0.001). However, bone tissue concentrations of HCY, SAH, and SAM were similar in the two groups. Fmax, B.Ar./T.Ar., OC, and CTX did not differ between VitDef and Co animals, indicating that bone quality was not affected. Folate and vitamin B(12) deficiency induces distinct HHCY but has no effect on bone health in otherwise healthy adult rats. The unchanged HCY metabolism in bone is the most probable explanation for the missing effect of the vitamin-free diet on bone.

Occurrence of vasospasm and infarction in relation to a focal monitoring sensor in patients after SAH: placing a bet when placing a probe?

INTRODUCTION Vasospastic brain infarction is a devastating complication of aneurysmal subarachnoid hemorrhage (SAH). Using a probe for invasive monitoring of brain tissue oxygenation or blood flow is highly focal and may miss the site of cerebral vasospasm (CVS). Probe placement is based on the assumption that the spasm will occur either at the dependent vessel territory of the parent artery of the ruptured aneurysm or at the artery exposed to the focal thick blood clot. We investigated the likelihood of a focal monitoring sensor being placed in vasospasm or infarction territory on a hypothetical basis. METHODS From our database we retrospectively selected consecutive SAH patients with angiographically proven (day 7-14) severe CVS (narrowing of vessel lumen >50%). Depending on the aneurysm location we applied a standard protocol of probe placement to detect the most probable site of severe CVS or infarction. We analyzed whether the placement was congruent with existing CVS/infarction. RESULTS We analyzed 100 patients after SAH caused by aneurysms located in the following locations: MCA (n = 14), ICA (n = 30), A1CA (n = 4), AcoA or A2CA (n = 33), and VBA (n = 19). Sensor location corresponded with CVS territory in 93% of MCA, 87% of ICA, 76% of AcoA or A2CA, but only 50% of A1CA and 42% of VBA aneurysms. The focal probe was located inside the infarction territory in 95% of ICA, 89% of MCA, 78% of ACoA or A2CA, 50% of A1CA and 23% of VBA aneurysms. CONCLUSION The probability that a single focal probe will be situated in the territory of severe CVS and infarction varies. It seems to be reasonably accurate for MCA and ICA aneurysms, but not for ACA or VBA aneurysms.

Investigations on an egyptian coffin and mummified head from Burgdorf Museum, Switzerland - A case of a historical puzzle

In the Burgdorf Museum of Ethnology, a mummy rests in a coffin. According to the inventory book, it was purchased from the Cairo Egyptian museum in 1926. The coffin was now examined by Egyptologists and the mummy was radiocarbon dated and examined by Anthropologists. The aim of the study was to compare the results and to check whether mummy and coffin actually belong together. The skull was examined morphological-anthropologically and by CT as a “blank sample”. Coffin and skull imply that the individual was female. The coffin dates to the Ptolemaic period. Only skull bones are preserved, the ethmoid is damaged. CT images Show resinous substances, bone fragments and brain remnants inside the skull. The ethmoid bone was probably foraminated during the mummification process and thus ended up inside the skull. The individual was mummified between the New Kingdom and the Ptolemaic period. Due to its style, it is most probable that the coffin comes from the Gamhud necropolis. The Burgdorf museum of ethnology inventory book chronicles were largely falsified by the examinations. There is a time gap between coffin and the mummy, there are two possible interpretations: the body was mummified with older linen, or the mummy and the coffin do not belong together. The authors strongly advise further investigations.

Noble gas, CFC and other geochemical evidence for the age and origin of the Bath thermal waters, UK

The city of Bath is a World Heritage site and its thermal waters, the Roman Baths and new spa development rely on undisturbed flow of the springs (45 °C). The current investigations provide an improved understanding of the residence times and flow regime as basis for the source protection. Trace gas indicators including the noble gases (helium, neon, argon, krypton and xenon) and chlorofluorocarbons (CFCs), together with a more comprehensive examination of chemical and stable isotope tracers are used to characterise the sources of the thermal water and any modern components. It is shown conclusively by the use of 39Ar that the bulk of the thermal water has been in circulation within the Carboniferous Limestone for at least 1000 years. Other stable isotope and noble gas measurements confirm previous findings and strongly suggest recharge within the Holocene time period (i.e. the last 12 kyr). Measurements of dissolved 85Kr and chlorofluorocarbons constrain previous indications from tritium that a small proportion (<5%) of the thermal water originates from modern leakage into the spring pipe passing through Mesozoic valley fill underlying Bath. This introduces small amounts of O2 into the system, resulting in the Fe precipitation seen in the King’s Spring. Silica geothermometry indicates that the water is likely to have reached a maximum temperature of between 69–99 °C, indicating a most probable maximum circulation depth of ∼3 km, which is in line with recent geological models. The rise to the surface of the water is sufficiently indirect that a temperature loss of >20 °C is incurred. There is overwhelming evidence that the water has evolved within the Carboniferous Limestone formation, although the chemistry alone cannot pinpoint the geometry of the recharge area or circulation route. For a likely residence time of 1–12 kyr, volumetric calculations imply a large storage volume and circulation pathway if typical porosities of the limestone at depth are used, indicating that much of the Bath-Bristol basin must be involved in the water storage.

Characterization of the Effect of the Mitochondrial Protein Hint2 on Intracellular Ca2+ dynamics

Hint2, one of the five members of the superfamily of the histidine triad AMP-lysine hydrolase proteins, is expressed in mitochondria of various cell types. In human adrenocarcinoma cells, Hint2 modulates Ca2+ handling by mitochondria. As Hint2 is highly expressed in hepatocytes, we investigated if this protein affects Ca2+ dynamics in this cell type. We found that in hepatocytes isolated from Hint2−/− mice, the frequency of Ca2+ oscillations induced by 1 μM noradrenaline was 150% higher than in the wild-type. Using spectrophotometry, we analyzed the rates of Ca2+ pumping in suspensions of mitochondria prepared from hepatocytes of either wild-type or Hint2−/− mice; we found that Hint2 accelerates Ca2+ pumping into mitochondria. We then resorted to computational modeling to elucidate the possible molecular target of Hint2 that could explain both observations. On the basis of a detailed model for mitochondrial metabolism proposed in another study, we identified the respiratory chain as the most probable target of Hint2. We then used the model to predict that the absence of Hint2 leads to a premature opening of the mitochondrial permeability transition pore in response to repetitive additions of Ca2+ in suspensions of mitochondria. This prediction was then confirmed experimentally.

[Therapy-resistant pneumonia]

We report the case of a 72 year old patient with B-symptoms and a persistent pulmonary infiltrate despite an antibiotic therapy. Buds of granulation tissue were found by transbronchial biopsy proving an organizing pneumonia. B-Symptoms and pulmonary infiltrate were improved immediately by a therapy with steroids. Even though there were reasons for a secondary organizing pneumonia due to a known chronic lymphocytic leukemia and a pneumonia treated four months before, we consider a cryptogenic organizing pneumonia as most probable.

Mutations upstream of fabI in triclosan resistant Staphylococcus aureus strains are associated with elevated fabI gene expression

Background The enoyl-acyl carrier protein (ACP) reductase enzyme (FabI) is the target for a series of antimicrobial agents including novel compounds in clinical trial and the biocide triclosan. Mutations in fabI and heterodiploidy for fabI have been shown to confer resistance in S. aureus strains in a previous study. Here we further determined the fabI upstream sequence of a selection of these strains and the gene expression levels in strains with promoter region mutations. Results Mutations in the fabI promoter were found in 18% of triclosan resistant clinical isolates, regardless the previously identified molecular mechanism conferring resistance. Although not significant, a higher rate of promoter mutations were found in strains without previously described mechanisms of resistance. Some of the mutations identified in the clinical isolates were also detected in a series of laboratory mutants. Microarray analysis of selected laboratory mutants with fabI promoter region mutations, grown in the absence of triclosan, revealed increased fabI expression in three out of four tested strains. In two of these strains, only few genes other than fabI were upregulated. Consistently with these data, whole genome sequencing of in vitro selected mutants identified only few mutations except the upstream and coding regions of fabI, with the promoter mutation as the most probable cause of fabI overexpression. Importantly the gene expression profiling of clinical isolates containing similar mutations in the fabI promoter also showed, when compared to unrelated non-mutated isolates, a significant up-regulation of fabI. Conclusions In conclusion, we have demonstrated the presence of C34T, T109G, and A101C mutations in the fabI promoter region of strains with fabI up-regulation, both in clinical isolates and/or laboratory mutants. These data provide further observations linking mutations upstream fabI with up-regulated expression of the fabI gene.

Measurements of neutrino oscillation in appearance and disappearance channels by the T2K experiment with 6.6×10²⁰ protons on target

We report on measurements of neutrino oscillation using data from the T2K long-baseline neutrino experiment collected between 2010 and 2013. In an analysis of muon neutrino disappearance alone, we find the following estimates and 68% confidence intervals for the two possible mass hierarchies: Normal Hierarchy: sin²θ₂₃= 0.514+0.055−0.056 and ∆m²_32 = (2.51 ± 0.10) × 10⁻³ eV²/c⁴ Inverted Hierarchy: sin²θ₂₃= 0.511 ± 0.055 and ∆m²_13 = (2.48 ± 0.10) × 10⁻³ eV²/c⁴ The analysis accounts for multi-nucleon mechanisms in neutrino interactions which were found to introduce negligible bias. We describe our first analyses that combine measurements of muon neutrino disappearance and electron neutrino appearance to estimate four oscillation parameters, |∆m^2|, sin²θ₂₃, sin²θ₁₃, δCP , and the mass hierarchy. Frequentist and Bayesian intervals are presented for combinations of these parameters, with and without including recent reactor measurements. At 90% confidence level and including reactor measurements, we exclude the region δCP = [0.15, 0.83]π for normal hierarchy and δCP = [−0.08, 1.09]π for inverted hierarchy. The T2K and reactor data weakly favor the normal hierarchy with a Bayes Factor of 2.2. The most probable values and 68% 1D credible intervals for the other oscillation parameters, when reactor data are included, are: sin²θ₂₃= 0.528+0.055−0.038 and |∆m²_32| = (2.51 ± 0.11) × 10⁻³ eV²/c⁴.

Ruminant rhombencephalitis-associated Listeria monocytogenes alleles linked to a multilocus variable-number tandem-repeat analysis complex

Listeria monocytogenes is among the most important food-borne pathogens and is well adapted to persist in the environment. To gain insight into the genetic relatedness and potential virulence of L. monocytogenes strains causing central nervous system (CNS) infections, we used multilocus variable-number tandem-repeat analysis (MLVA) to subtype 183 L. monocytogenes isolates, most from ruminant rhombencephalitis and some from human patients, food, and the environment. Allelic-profile-based comparisons grouped L. monocytogenes strains mainly into three clonal complexes and linked single-locus variants (SLVs). Clonal complex A essentially consisted of isolates from human and ruminant brain samples. All but one rhombencephalitis isolate from cattle were located in clonal complex A. In contrast, food and environmental isolates mainly clustered into clonal complex C, and none was classified as clonal complex A. Isolates of the two main clonal complexes (A and C) obtained by MLVA were analyzed by PCR for the presence of 11 virulence-associated genes (prfA, actA, inlA, inlB, inlC, inlD, inlE, inlF, inlG, inlJ, and inlC2H). Virulence gene analysis revealed significant differences in the actA, inlF, inlG, and inlJ allelic profiles between clinical isolates (complex A) and nonclinical isolates (complex C). The association of particular alleles of actA, inlF, and newly described alleles of inlJ with isolates from CNS infections (particularly rhombencephalitis) suggests that these virulence genes participate in neurovirulence of L. monocytogenes. The overall absence of inlG in clinical complex A and its presence in complex C isolates suggests that the InlG protein is more relevant for the survival of L. monocytogenes in the environment.

Risk factors for invasive aspergillosis in neutropenic patients with hematologic malignancies

Risk factors for invasive aspergillosis (IA) are incompletely identified and may undergo changes due to differences in medical practice. A cohort of 189 consecutive, adult patients with neutropenia hospitalized in the hemato-oncology ward of the University hospital Berne between 1995 and 1999 were included in a retrospective study to assess risk factors for IA. In total, 45 IA cases (nine proven, three probable, 33 possible), 11 patients with refractory fever and 133 controls were analyzed. IA cases had more often acute leukemia or myelodysplastic syndrome (MDS) (88 vs 38%, P < 0.001) and a longer duration of neutropenia (mean 20.6 vs 9.9 days, P < 0.001). They also had fewer neutropenic episodes during the preceding 6 months (mean 0.42 vs 1.03, P < 0.001), that is, confirmed (82%) and probable (73%) IA occurred most often during the induction cycle. A short time interval ( < or = 14 days) between neutropenic episodes increased the risk of IA four-fold (P = 0.06). Bacteremia, however, was not related to the number of preceding neutropenic episodes. Therefore, neutropenic patients with leukemia or MDS have the highest risk of IA. The risk is highest during the first induction cycle of treatment and increases with short-time intervals between treatment cycles.

Splitting of a prevalent Mycobacterium bovis spoligotype by variable-number tandem-repeat typing reveals high heterogeneity in an evolving clonal group

Mycobacterium bovis populations in countries with persistent bovine tuberculosis usually show a prevalent spoligotype with a wide geographical distribution. This study applied mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) typing to a random panel of 115 M. bovis isolates that are representative of the most frequent spoligotype in the Iberian Peninsula, SB0121. VNTR typing targeted nine loci: ETR-A (alias VNTR2165), ETR-B (VNTR2461), ETR-D (MIRU4, VNTR580), ETR-E (MIRU31, VNTR3192), MIRU26 (VNTR2996), QUB11a (VNTR2163a), QUB11b (VNTR2163b), QUB26 (VNTR4052), and QUB3232 (VNTR3232). We found a high degree of diversity among the studied isolates (discriminatory index [D] = 0.9856), which were split into 65 different MIRU-VNTR types. An alternative short-format MIRU-VNTR typing targeting only the four loci with the highest variability values was found to offer an equivalent discriminatory index. Minimum spanning trees using the MIRU-VNTR data showed the hypothetical evolution of an apparent clonal group. MIRU-VNTR analysis was also applied to the isolates of 176 animals from 15 farms infected by M. bovis SB0121; in 10 farms, the analysis revealed the coexistence of two to five different MIRU types differing in one to six loci, which highlights the frequency of undetected heterogeneity.

Efficient estimation of the total number of acini in adult rat lung

Pulmonary airways are subdivided into conducting and gas-exchanging airways. An acinus is defined as the small tree of gas-exchanging airways, which is fed by the most distal purely conducting airway. Until now a dissector of five consecutive sections or airway casts were used to count acini. We developed a faster method to estimate the number of acini in young adult rats. Right middle lung lobes were critical point dried or paraffin embedded after heavy metal staining and imaged by X-ray micro-CT or synchrotron radiation-based X-rays tomographic microscopy. The entrances of the acini were counted in three-dimensional (3D) stacks of images by scrolling through them and using morphological criteria (airway wall thickness and appearance of alveoli). Segmentation stopper were placed at the acinar entrances for 3D visualizations of the conducting airways. We observed that acinar airways start at various generations and that one transitional bronchiole may serve more than one acinus. A mean of 5612 (±547) acini per lung and a mean airspace volume of 0.907 (±0.108) μL per acinus were estimated. In 60-day-old rats neither the number of acini nor the mean acinar volume did correlate with the body weight or the lung volume.

Estimating the Reproduction Number of Ebola Virus (EBOV) During the 2014 Outbreak in West Africa

The 2014 Ebola virus (EBOV) outbreak in West Africa is the largest outbreak of the genus Ebolavirus to date. To better understand the spread of infection in the affected countries, it is crucial to know the number of secondary cases generated by an infected index case in the absence and presence of control measures, i.e., the basic and effective reproduction number. In this study, I describe the EBOV epidemic using an SEIR (susceptible-exposed-infectious-recovered) model and fit the model to the most recent reported data of infected cases and deaths in Guinea, Sierra Leone and Liberia. The maximum likelihood estimates of the basic reproduction number are 1.51 (95% confidence interval [CI]: 1.50-1.52) for Guinea, 2.53 (95% CI: 2.41-2.67) for Sierra Leone and 1.59 (95% CI: 1.57-1.60) for Liberia. The model indicates that in Guinea and Sierra Leone the effective reproduction number might have dropped to around unity by the end of May and July 2014, respectively. In Liberia, however, the model estimates no decline in the effective reproduction number by end-August 2014. This suggests that control efforts in Liberia need to be improved substantially in order to stop the current outbreak.