Ein neues, unkompliziert auszuführendes Verfahren zur Bestimmung kleiner Konzentrationen an Wasser in organischen Lösungsmitteln

A new procedure for the determination of water (even in trace amounts) in organic solvents is described. The solvatochromism of the pyridiniumphenol betaine, E T30, determined by a simple UV-absorption measurement, together with a two-parameter equation, permits an exact determination. The procedure is rapid and is, therefore, an alternative to the Karl-Fischer titration

Y-chromosomal variation in the Czech Republic

To analyze the contribution of the Czech population to the Y-chromosome diversity landscape of Europe and to reconstruct past demographic events, we typed 257 males from five locations for 21 UEPs. Moreover, 141 carriers of the three most common haplogroups were typed for 10 microsatellites and coalescent analyses applied. Sixteen Hg's characterized by derived alleles were identified, the most common being R1a-SRY10831 and P-DYS257*(xR1a). The pool of haplogroups within I-M170 represented the third most common clade. Overall, the degree of population structure was low. The ages for Hg I-M170, P-DYS257*(xR1a), and R1a-SRY10831 appeared to be comparable and compatible with their presence during or soon after the LGM. A signal of population growth beginning in the first millennium B.C. was detected. Its similarity among the three most common Hg's indicated that growth was characteristic for a gene pool that already contained all of them. The Czech population appears to be influenced, to a very moderate extent, by genetic inputs from outside Europe in the post-Neolithic and historical times. Population growth postdated the archaeologically documented introduction of Neolithic technology and the estimated central value coincides with a period of repeated changes driven by the development of metal technologies and the associated social and trade organization

Ein neues, unkompliziertes Verfahren zur Bestimmung der Zusammensetzung binärer Flüssigkeitsgemische

Ein neues Verfahren zur Bestimmung der Zusammensetzung binärer Flüssigkeitsgemische mit Hilfe solvatochromer Farbstoffe wird beschrieben. Die Analyse erfolgt durch einfache UV/VIS-Absorptionsmessung und ist unter Verwendung einer Zwei-Parameter-Gleichung ein exakter Schnelltest

Determination of pH in Regions of the Midguts of Acaridid Mites

The pH of the guts of mites strongly affects their digestive processes. This study was carried out to determine the pH in the guts of 12 species of stored product and house dust mites. Eighteen pH indicators were chosen and offered to the mites in the feeding biotest. Based on the color changes of the indicators, the gut contents of acaridid mites were determined to be within a pH range of 4 to neutral. The gut contents showed a gradient in pH from the anterior to the posterior part. The anterior midgut (ventriculus and caeca) of most species had a pH ranging from 4.5 to 5, or slightly more alkaline for most of the species, while the middle midgut (intercolon/colon) had a pH of 5 to 6. Finally, the pH of the posterior midgut (postcolon) was between 5.5 and 7. Except for Dermatophagoides spp., no remarkable differences in the pH of the gut were observed among the tested species. Dermatophagoides spp. had a more acidic anterior midgut (a pH of 4 to 5) and colon (a pH of 5) with postcolon (a pH of below 6). The results characterizing in vivo conditions in the mite gut offer useful information to study the activity of mite digestive enzymes including their inhibitors and gut microflora

Patterns of male-specific inter-population divergence in Europe, West Asia and North Africa

We typed 1801 males from 55 locations for the Y-specific binary markers YAP! DYZ3, SRY10831 and the (CA)n microsatellites YCAII and DYS413. Phylogenetic relationships of chromosomes with the same binary haplotype were condensed in seven large one-step networks! which accounted for 95% of all chromosomes. Their coalescence ages were estimated based on microsatellite diversity. The three largest and oldest networks undergo sharp frequency changes in three areas. The more recent network; 3.1A clearly discriminates between Western and Eastern European populations. Pairwise Pst showed an overall increment with increasing geographic distance but with a slope greatly reduced when compared to previous reports. BI sectioning the entire data set according to geographic and linguistic criteria, we found higher Fst-on-distance slopes within Europe than in West Asia or across the tno continents

Explicit Kundt type II and N solutions as gravitational waves in various type D and O universes

A particular yet large class of non-diverging solutions which admits a cosmological constant, electromagnetic field, pure radiation and/or general non-null matter component is explicitly presented. These spacetimes represent exact gravitational waves of arbitrary profiles which propagate in background universes such as Minkowski, conformally flat (anti-)de Sitter, Edgar-Ludwig, Bertotti-Robinson, and type D (anti-)Nariai or Plebanski-Hacyan spaces, and their generalizations. All possibilities are discussed and are interpreted using a unifying simple metric form. Sandwich and impulsive waves propagating in the above background spaces with different geometries and matter content can easily be constructed. New solutions are identified, e.g. type D pure radiation or explicit type II electrovacuum waves in (anti-)Nariai universe. It is also shown that, in general, there are no conformally flat Einstein-Maxwell fields with a non-vanishing cosmological constant.Comment: 17 pages, LaTeX 2e. v2: added two references concerning generalized Kerr-Schild transformations, minor changes in the tex

RhoH Regulates Subcellular Localization of ZAP-70 and Lck in T Cell Receptor Signaling

RhoH is an hematopoietic-specific, GTPase-deficient Rho GTPase that plays a role in T development. We investigated the mechanisms of RhoH function in TCR signaling. We found that the association between Lck and CD3ζ was impaired in RhoH-deficient T cells, due to defective translocation of both Lck and ZAP-70 to the immunological synapse. RhoH with Lck and ZAP-70 localizes in the detergent-soluble membrane fraction where the complex is associated with CD3ζ phosphorylation. To determine if impaired translocation of ZAP-70 was a major determinant of defective T cell development, Rhoh-/- bone marrow cells were transduced with a chimeric myristoylation-tagged ZAP-70. Myr-ZAP-70 transduced cells partially reversed the in vivo defects of RhoH-associated thymic development and TCR signaling. Together, our results suggest that RhoH regulates TCR signaling via recruitment of ZAP-70 and Lck to CD3ζ in the immunological synapse. Thus, we define a new function for a RhoH GTPase as an adaptor molecule in TCR signaling pathway

Constitutively active Lyn kinase causes a cutaneous small vessel vasculitis and liver fibrosis syndrome

Neutrophilic inflammation is a hallmark of many monogenic autoinflammatory diseases; pathomechanisms that regulate extravasation of damaging immune cells into surrounding tissues are poorly understood. Here we identified three unrelated boys with perinatal-onset of neutrophilic cutaneous small vessel vasculitis and systemic inflammation. Two patients developed liver fibrosis in their first year of life. Next-generation sequencing identified two de novo truncating variants in the Src-family tyrosine kinase, LYN, p.Y508*, p.Q507* and a de novo missense variant, p.Y508F, that result in constitutive activation of Lyn kinase. Functional studies revealed increased expression of ICAM-1 on induced patient-derived endothelial cells (iECs) and of β2-integrins on patient neutrophils that increase neutrophil adhesion and vascular transendothelial migration (TEM). Treatment with TNF inhibition improved systemic inflammation; and liver fibrosis resolved on treatment with the Src kinase inhibitor dasatinib. Our findings reveal a critical role for Lyn kinase in modulating inflammatory signals, regulating microvascular permeability and neutrophil recruitment, and in promoting hepatic fibrosis

Multiple Advantageous Amino Acid Variants in the NAT2 Gene in Human Populations

Background: Genetic variation at NAT2 has been long recognized as the cause of differential ability to metabolize a wide variety of drugs of therapeutic use. Here, we explore the pattern of genetic variation in 12 human populations that significantly extend the geographic range and resolution of previous surveys, to test the hypothesis that different dietary regimens and lifestyles may explain inter-population differences in NAT2 variation. Methodology/Principal Findings: The entire coding region was resequenced in 98 subjects and six polymorphic positions were genotyped in 150 additional subjects. A single previously undescribed variant was found (34T>C; 12Y>H). Several aspects of the data do not fit the expectations of a neutral model, as assessed by coalescent simulations. Tajima's D is positive in all populations, indicating an excess of intermediate alleles. The level of between-population differentiation is low, and is mainly accounted for by the proportion of fast vs. slow acetylators. However, haplotype frequencies significantly differ across groups of populations with different subsistence. Conclusions/Significance: Data on the structure of haplotypes and their frequencies are compatible with a model in which slow-causing variants were present in widely dispersed populations before major shifts to pastoralism and/or agriculture. In this model, slow-causing mutations gained a selective advantage in populations shifting from hunting-gathering to pastoralism/agriculture. We suggest the diminished dietary availability of folates resulting from the nutritional shift, as the possible cause of the fitness increase associated to haplotypes carrying mutations that reduce enzymatic activity. © 2008 Luca et al

Phosphoprotein Associated with Glycosphingolipid-Enriched Microdomains Differentially Modulates Src Kinase Activity in Brain Maturation

Src family kinases (SFK) control multiple processes during brain development and function. We show here that the phosphoprotein associated with glycosphigolipid-enriched microdomains (PAG)/Csk binding protein (Cbp) modulates SFK activity in the brain. The timing and localization of PAG expression overlap with Fyn and Src, both of which we find associated to PAG. We demonstrate in newborn (P1) mice that PAG negatively regulates Src family kinases (SFK). P1 Pag1-/- mouse brains show decreased recruitment of Csk into lipid rafts, reduced phosphorylation of the inhibitory tyrosines within SFKs, and an increase in SFK activity of >/ = 50%. While in brain of P1 mice, PAG and Csk are highly and ubiquitously expressed, little Csk is found in adult brain suggesting altered modes of SFK regulation. In adult brain Pag1-deficiency has no effect upon Csk-distribution or inhibitory tyrosine phosphorylation, but kinase activity is now reduced (−20–30%), pointing to the development of a compensatory mechanism that may involve PSD93. The distribution of the Csk-homologous kinase CHK is not altered. Importantly, since the activities of Fyn and Src are decreased in adult Pag1-/- mice, thus presenting the reversed phenotype of P1, this provides the first in vivo evidence for a Csk-independent positive regulatory function for PAG in the brain