Assessment of LV diastolic filling using color M-mode Doppler echocardiography: validation in a new hydraulic model

The effect of LV properties on v _p and the E/v _p ratio remains a matter of debate. Therefore, the objective of this study is to explore – in a new hydraulic model – the individual contributions of LV relaxation, filling pressure and compliance in changes of E, v _p and E/v _p for different stages of diastolic function. A new hydraulic model, consisting of an open cylindrical LA connected to an ellipsoidal LV, is designed. E and v _p are measured for varying values of (45–60–90 ms), LV compliance (0.45–1.35 ml/mmHg) and filling pressure (3–10–30 mmHg). The results are used for predicting the evolution of E, v _p and E/v _p during different stages of diastolic function. An increase in compliance decreases E, whereas it augments v _p. v _p is less load-dependent than E. E decreases with delayed relaxation, increases for the case of pseudonormalisation, and becomes higher than the reference values during restrictive filling. The v _p value is lower for the case of delayed relaxation than for the reference situation. During pseudonormalisation, the value of v _p remains lower than the reference value but higher than the value for delayed relaxation. . v _p further decreases during restrictive filling. In conclusion, the effect of simultaneous changes in compliance and loading counterbalance changes in v _p. Therefore, under normal physiologic conditions where load and compliance are coupled, v _p is apparently load-insensitive and E/v _p increases as filling pressure increases. Moreover, in the different stages of diastolic dysfunction, due to the interference of the co-varying relaxation, the increase in E/v _p is more pronounced.     

Immunogenic proteins of Helicobacter pullorum,Helicobacter bilis and Helicobacter hepaticus identified by two-dimensional gel electrophoresis and immunoblotting

The ecological niches occupied by various species of Helicobacter are not yet known and the full spectrum of diseases associated with Helicobacter infections are not yet defined. Since these fastidious microaerofilic bacteria require special growth conditions new and improved molecular and serologic diagnostic methods have been developed to increase our understanding of their pathogenesis and virulence characteristics. Immunogenic cell surface proteins of Helicobacter pullorum, Helicobacter bilis, and Helicobacter hepaticus were characterised by proteomic techniques using two-dimensional electrophoresis and immunoblotting with antisera from immunised rabbits. Cross-reactivity between the three Helicobacter species were analysed after a four-step cross-absorption experiment. For H. pullorum, H. bilis and H. hepaticus 21, 13 and 27 specific immunogenic proteins, respectively, were identified. These proteins could be of important sero-diagnostic value for analyses of sera from humans, laboratory animals and for the veterinarian field.     

Optical Absorption‐Based In Situ Characterization of Halide Perovskites

Halide perovskites have emerged as materials for high‐performance optoelectronic devices. Often, progress made to date in terms of higher efficiency and stability is based on increasing material complexity, i.e., formation of multicomponent halide perovskites with multiple cations and anions. In this review article, the use of in situ optical methods, namely, photoluminescence (PL) and UV‐vis, that provide access to the relevant time and length scales to ascertain chemistry–property relationships by monitoring evolving properties is discussed. Additionally, because halide perovskites are electron/ion conductors and prone to solid‐state ion transport under various external stimuli, application of these optical methods in the context of ionic movement is described to reveal mechanistic insights. Finally, examples of using in situ PL and UV‐vis to study degradation and phase transitions are reviewed to demonstrate the wealth of information that can be obtained regarding many different aspects of ongoing research activities in the field of halide perovskites.     

Changes in kidney transamidinase activity during development in male and female rats

The developmental changes in the activity of kidney transamidinase in male and female rats were investigated. The activity in both sexes increased rapidly after birth, reaching adult levels at 4 days of age. After weaning, the activity in male rats remained constant, while in female rats i t declined to 60% ol that in males. Thus, transamidinase is in the neonatal cluster of enzyme differentiation.     

Quantitative Peptidomics of Purkinje Cell Degeneration Mice

Cytosolic carboxypeptidase 1 (CCP1) is a metallopeptidase that removes C-terminal and side-chain glutamates from tubulin. The Purkinje cell degeneration (pcd) mouse lacks CCP1 due to a mutation. Previously, elevated levels of peptides derived from cytosolic and mitochondrial proteins were found in adult pcd mouse brain, raising the possibility that CCP1 functions in the degradation of intracellular peptides. To test this hypothesis, we used a quantitative peptidomics technique to compare peptide levels in wild-type and pcd mice, examining adult heart, spleen, and brain, and presymptomatic 3 week-old amygdala and cerebellum. Contrary to adult mouse brain, young pcd brain and adult heart and spleen did not show a large increase in levels of intracellular peptides. Unexpectedly, levels of peptides derived from secretory pathway proteins were altered in adult pcd mouse brain. The pattern of changes for the intracellular and secretory pathway peptides in pcd mice was generally similar to the pattern observed in mice lacking primary cilia. Collectively, these results suggest that intracellular peptide accumulation in adult pcd mouse brain is a secondary effect and is not due to a role of CCP1 in peptide turnover.     

Isolation of a highly pure archeocyte fraction from the fresh-water spongeEphydatia fluviatilis

Summary A pure archeocyte fraction was isolated from the fresh-water spongeEphydatia fluviatilis by density gradient centrifugation of dissociated cell suspensions. The nature and purity of the fraction were confirmed by electron microscopy.     

The Ca2+ Sensor Protein Swiprosin-1/EFhd2 Is Present in Neurites and Involved in Kinesin-Mediated Transport in Neurons

Swiprosin-1/EFhd2 (EFhd2) is a cytoskeletal Ca²⁺ sensor protein strongly expressed in the brain. It has been shown to interact with mutant tau, which can promote neurodegeneration, but nothing is known about the physiological function of EFhd2 in the nervous system. To elucidate this question, we analyzed EFhd2^−/−/lacZ reporter mice and showed that lacZ was strongly expressed in the cortex, the dentate gyrus, the CA1 and CA2 regions of the hippocampus, the thalamus, and the olfactory bulb. Immunohistochemistry and western blotting confirmed this pattern and revealed expression of EFhd2 during neuronal maturation. In cortical neurons, EFhd2 was detected in neurites marked by MAP2 and co-localized with pre- and post-synaptic markers. Approximately one third of EFhd2 associated with a biochemically isolated synaptosome preparation. There, EFhd2 was mostly confined to the cytosolic and plasma membrane fractions. Both synaptic endocytosis and exocytosis in primary hippocampal EFhd2^−/− neurons were unaltered but transport of synaptophysin-GFP containing vesicles was enhanced in EFhd2^−/− primary hippocampal neurons, and notably, EFhd2 inhibited kinesin mediated microtubule gliding. Therefore, we found that EFhd2 is a neuronal protein that interferes with kinesin-mediated transport.     

Polar body mutation load analysis in a patient with A3243G tRNALeu(UUR) point mutation

Diseases associated with point mutations in the mitochondrial DNA (mtDNA) are maternally inherited. We evaluated whether pre-implantation genetic diagnosis, based on polar body mutation load detection could be used to distinguish healthy from affected oocytes. Restriction Fragment Length Polymorphism (RFLP) analysis was used and validated, to determine A3243G tRNA(Leu(UUR)) mutation load in metaphase II oocytes and their respective first polar bodies. The results of this study show for the first time that the mutation load measured in the polar bodies correlates well with the mutation load in the respective oocytes. Therefore, human polar body analysis can be used as diagnostic tool to prevent transmission of mitochondrial disorders.