Simulating a reference medium for determining bacterial growth in hospital wastewater for Raman spectroscopic investigation

Wastewater is a very complex and diverse medium, which despite low nutrient density still harbors bacteria. Especially the wastewater from hospitals contains a high germ load. However, wastewater is also very variable and differs not only from day to day, but also from house to house. Since wastewater is always changing and medium has an impact on Raman spectra of bacteria, it is necessary to find a surrogate material in which bacteria can be cultured to mimic a real hospital wastewater sample. In this study, we investigate two different artificial wastewaters for their abilities as a good alternative to real wastewater from the Jena University Hospital and to serve as a reference material for bacterial cultivation with subsequent Raman measurement. Each of the artificial wastewater on its own was not suitable to be used as a reference medium. Only the combination of the two simulated wastewaters achieved satisfactory results in the Raman spectroscopic identification of bacteria from real wastewater. These results could be used later in new experiments as a reference dataset to identify bacteria from real hospital wastewater samples.

Bacterial phenotype dependency from CO2 measured by Raman spectroscopy

In recent years, Raman spectroscopy has become an established method to study medical, biological or environmental samples. Since Raman spectroscopy is a phenotypic method, many parameters can influence the spectra. One of these parameters is the concentration of CO₂, as this never remains stable in nature, but always adjusts itself in a dynamic equilibrium. So, it is obvious that the concentration of CO₂ cannot be controlled but it might have a big impact on the bacteria and bacterial composition in medical samples. When using a phenotypic method like Raman spectroscopy it is also important to know the influence of CO₂ to the dataset. To investigate the influence of CO₂ towards Raman spectra we cultivated E. coli at different concentration of CO₂ since this bacterium is able to switch metabolism from aerobic to microaerophilic conditions. After applying statistic methods small changes in the spectra became visible and it was even possible to observe the change of metabolism in this species according to the concentration of CO₂.

Physical fitness and plasma leptin in women with recent gestational diabetes

Aims/Hypothesis

Low physical fitness (PF) is a risk factor for type 2 diabetes mellitus (T2D). Women with a history of gestational diabetes (GDM) are at risk for T2D at a young age, but the role of PF in this population is not clear. PF has also been found to correlate inversely with plasma leptin in previous studies. Here, we examine whether women who had GDM have lower PF than women after a normoglycemic pregnancy and, second, whether PF is associated with plasma leptin, independently of body fat mass.

Methods

Cross-sectional analysis of 236 participants in the PPSDiab Study (cohort study of women 3–16 months after delivery, 152 after gestational diabetes (pGDM), 84 after normoglycemic pregnancy (control subjects); consecutively recruited 2011–16); medical history, physical examination with bioelectrical impedance analysis (BIA), whole body magnetic resonance imaging (MRI) (n = 154), 5-point oral glucose tolerance test, cardiopulmonary exercise testing, clinical chemistry including fasting plasma leptin; statistical analysis with Mann–Whitney U and t -test, Spearman correlation coefficient, multiple linear regression.

Results

Women pGDM had lower maximally achieved oxygen uptake (VO_2peak/kg: 25.7(21.3–29.9) vs. 30.0(26.6–34.1)ml/min/kg; total VO_2peak: 1733(1552–2005) vs. 1970(1767–2238)ml/min; p<0.0001 for both), and maximum workload (122.5(105.5–136.5) vs. 141.0(128.5–159.5)W; p<0.0001). Fasting plasma leptin correlated inversely with PF (VO_2peak/kg ρ = -0.72 p<0.0001; VO_2peak ρ = -0.16 p = 0.015; max. load ρ = -0.35 p<0.0001). These associations remained significant with adjustment for body mass index, or for body fat mass (BIA and MRI).

Conclusions/Interpretation

Women with a recent history of GDM were less fit than control subjects. Low PF may therefore contribute to the risk for T2D after GDM. This should be tested in intervention studies. Low PF also associated with increased leptin levels–independently of body fat. PF may therefore influence leptin levels and signaling. This hypothesis requires further investigation.

Relating structure and function of inner hair cell ribbon synapses

In the mammalian cochlea, sound is encoded at synapses between inner hair cells (IHCs) and type I spiral ganglion neurons (SGNs). Each SGN receives input from a single IHC ribbon-type active zone (AZ) and yet SGNs indefatigably spike up to hundreds of Hz to encode acoustic stimuli with submillisecond precision. Accumulating evidence indicates a highly specialized molecular composition and structure of the presynapse, adapted to suit these high functional demands. However, we are only beginning to understand key features such as stimulus-secretion coupling, exocytosis mechanisms, exo-endocytosis coupling, modes of endocytosis and vesicle reformation, as well as replenishment of the readily releasable pool. Relating structure and function has become an important avenue in addressing these points and has been applied to normal and genetically manipulated hair cell synapses. Here, we review some of the exciting new insights gained from recent studies of the molecular anatomy and physiology of IHC ribbon synapses.

RUNX1/ETO blocks selectin-mediated adhesion via epigenetic silencing of PSGL-1

RUNX1/ETO (RE), the t(8;21)-derived leukemic transcription factor associated with acute myeloid leukemia (AML) development, deregulates genes involved in differentiation, self-renewal and proliferation. In addition, these cells show differences in cellular adhesion behavior whose molecular basis is not well understood. Here, we demonstrate that RE epigenetically silences the gene encoding P-Selectin Glycoprotein Ligand-1 (PSGL-1) and downregulates PSGL-1 expression in human CD34+ and murine lin− hematopoietic progenitor cells. Levels of PSGL-1 inversely and dose-dependently correlate with RE oncogene levels. However, a DNA-binding defective mutant fails to downregulate PSGL-1. We show by ChIP experiments that the PSGL-1 promoter is a direct target of RE and binding is accompanied by high levels of the repressive chromatin mark histone H3K27me3. In t(8;21)+ Kasumi-1 cells, PSGL-1 expression is completely restored at both the mRNA and cell surface protein levels following RE downregulation with short hairpin RNA (shRNA) or RE inhibition with tetramerization-blocking peptides, and at the promoter H3K27me3 is replaced by the activating chromatin mark H3K9ac as well as by RNA polymerase II. Upregulation of PSGL-1 restores the binding of cells to P- and E-selectin and re-establishes myeloid-specific cellular adhesion while it fails to bind to lymphocyte-specific L-selectin. Overall, our data suggest that the RE oncoprotein epigenetically represses PSGL-1 via binding to its promoter region and thus affects the adhesive behavior of t(8;21)+ AML cells.

Antagonism between granulocytic maturation and deacetylase inhibitor-induced apoptosis in acute promyelocytic leukaemia cells

Background:

Transcriptional repression is a key mechanism driving leukaemogenesis. In acute promyelocytic leukaemia (APL), the fusion protein promyelocytic leukaemia-retinoic acid receptor-α fusion (PML-RARα) recruits transcriptional repressors to myeloid differentiation genes. All-trans-retinoic acid (ATRA) induces the proteasomal degradation of PML-RARα and granulocytic differentiation. Histone deacetylases (HDACs) fall into four classes (I–IV) and contribute to the transcription block caused by PML-RARα.

Methods:

Immunoblot, flow cytometry, and May-Grünwald–Giemsa staining were used to analyze differentiation and induction of apoptosis.

Results:

A PML-RARα- and ATRA-dependent differentiation programme induces granulocytic maturation associated with an accumulation of the myeloid transcription factor CCAAT/enhancer binding protein (C/EBP)ɛ and of the surface protein CD11b. While this process protects APL cells from inhibitors of class I HDAC activity, inhibition of all Zinc-dependent HDACs (classes I, II, and IV) with the pan-HDACi (histone deacetylase inhibitor(s)) LBH589 induces apoptosis of immature and differentiated APL cells. LBH589 can eliminate C/EBPɛ and the mitochondrial apoptosis regulator B-cell lymphoma (BCL)-xL in immature and differentiated NB4 cells. Thus, BCL-xL and C/EBPɛ are newly identified molecular markers for the efficacy of HDACi against APL cells.

Conclusions:

Our results could explain the therapeutic limitations occurring with ATRA and class I HDACi combinations. Pro-apoptotic effects caused by pan-HDAC inhibition are not blunted by ATRA-induced differentiation and may provide a clinically interesting alternative.

Active zone assembly and synaptic release

Neurotransmitter release at chemical synapses occurs when synaptic vesicles fuse to the presynaptic membrane at a specialized site termed the active zone. The depolarization-induced fusion is highly dependent on calcium ions, and, correspondingly, the transmission characteristics of synapses are thought to be influenced by the spatial arrangement of voltage-gated calcium channels with respect to vesicle release sites. Here, we review the involvement of the Drosophila Bruchpilot (BRP) protein in active zone assembly, a process that is required for the clustering of presynaptic calcium channels to ensure efficient vesicle release.

Liposomes for microcompartmentation of enzymes and their influence on catalytic activity

Modular systems for protein coupling have been applied for anchoring enzyme molecules on liposome surfaces. Two cytoplasmic model enzymes, alpha-amylase from Escherichia coli (EC. 3.2.1.1) and guanylate kinase from Saccharomyces cerevisiae (EC. 2.7.4.8), were directly coupled by a histidine-tag or indirectly via strep-tag and streptavidin or streptactin linker to a liposome membrane. Though the catalytic properties of the enzymes are generally maintained, stability and specific activity of the enzymes are modified after coupling and are especially influenced by the lipid used for the liposome assembly.

When girls versus boys play alone: nonsocial play and adjustment in kindergarten

The goal of the present study was to examine the relations between different forms of children's nonsocial play behaviors and adjustment in kindergarten. The participants in this study were 77 kindergarten children (38 boys, 39 girls; mean age = 66.16 months, SD = 4.11 months). Mothers completed ratings of child shyness and emotion dysregulation. Children's nonsocial play behaviors (reticent, solitary-passive. solitary active) were observed during free play. In addition, teachers rated child behavior problems (internalizing and externalizing) and social competence; academic achievement was assessed through child interviews. Results from regression analyses revealed that different types of nonsocial play were differentially associated with child characteristics and indices of adjustment. For some forms of nonsocial play, the nature of these associations differed significantly for boys and girls.

When girls versus boys play alone: nonsocial play and adjustment in kindergarten

The goal of the present study was to examine the relations between different forms of children's nonsocial play behaviors and adjustment in kindergarten. The participants in this study were 77 kindergarten children (38 boys, 39 girls; mean age = 66.16 months, SD = 4.11 months). Mothers completed ratings of child shyness and emotion dysregulation. Children's nonsocial play behaviors (reticent, solitary-passive. solitary active) were observed during free play. In addition, teachers rated child behavior problems (internalizing and externalizing) and social competence; academic achievement was assessed through child interviews. Results from regression analyses revealed that different types of nonsocial play were differentially associated with child characteristics and indices of adjustment. For some forms of nonsocial play, the nature of these associations differed significantly for boys and girls.

[Modification of blood coagulation by antihypertensive therapy? Effect of enalapril and hydrochlorothiazide on blood coagulation parameters in patients with essential hypertension]

An increased tendency of the blood to clot in patients with arterial hypertension is not desirable, since cardiovascular and cerebrovascular sequelae may be aggravated. Recently, activation of coagulation under ACE inhibition with captopril has been described. In an open, randomized study, we compared the influence of enalapril on various coagulation parameters with that of hydrochlorothiazide. In contrast to the latter, we detected no unfavorable influence of enalapril on the coagulation factors investigated. A transient increase in fibrin monomeres was observed in one patient each on enalapril and hydrochlorothiazide.