Kehlkopfveränderungen und plötzlicher Tod

Mehrere in letzter Zeit beobachtete Fälle eines ldquoplötzlichen Todesrdquo durch Kehlkopfveränderungen gaben Anlaß zur eingehenden Erörterung dieser Problematik, zumal im Institut für Rechtsmedizin der Universität München unter 10 747 Obduktionen in den Jahren 1949 bis 1970 nur 6 Fälle gefunden wurden. Nach einer kurzen Beschreibung des anatomischen Aufbaues vom Kehlkopf werden entsprechend der in der allgemeinen Pathologie benutzten Gliederung die 4 Faktoren angeführt, die ätiologisch Ursache eines Kehlkopfverschlusses sein können: 1. Fehlbildungen 2. Kreislaufstörungen 3. Entzündungen 4. Geschwulstbildungen. Jeder der genannten Faktoren wird gesondert erörtert und die Fälle aus unserem Beobachtungsgut ihnen entsprechend zugeordnet. Neben der Frage nach der rechtsmedizinischen Bedeutung derartiger Todesfälle wird die Schwierigkeit der Beurteilung mancher pathomorphologischer und feingeweblicher Befunde diskutiert. Gleichzeitig wird auf die oft leere Anamnese hingewiesen, so daß lebensrettende Maßnahmen, wie zum Beispiel die Notfalltracheotomie und anderes, gar nicht oder sehr spät einsetzen können. Abschließend wird die Problematik der forensischen Begutachtung diskutiert, die sich bei der Abgrenzung der Larynxzysten hinsichtlich ihrer Ätiologie ergibt. Hier ist die Abklärung eines Kausalzusammenhanges zu eventuell vorangegangenen Intubationen von besonderer Bedeutung

Validity of the Polar V800 heart rate monitor to measure RR intervals at rest

Purpose To assess the validity of RR intervals and short-term heart rate variability (HRV) data obtained from the Polar V800 heart rate monitor, in comparison to an electrocardiograph (ECG). Method Twenty participants completed an active orthostatic test using the V800 and ECG. An improved method for the identification and correction of RR intervals was employed prior to HRV analysis. Agreement of the data was assessed using intra-class correlation coefficients (ICC), Bland–Altman limits of agreement (LoA), and effect size (ES). Results A small number of errors were detected between ECG and Polar RR signal, with a combined error rate of 0.086 %. The RR intervals from ECG to V800 were significantly different, but with small ES for both supine corrected and standing corrected data (ES 0.999 for both supine and standing corrected intervals. When analysed with the same HRV software no significant differences were observed in any HRV parameters, for either supine or standing; the data displayed small bias and tight LoA, strong ICC (>0.99) and small ES (≤0.029). Conclusions The V800 improves over previous Polar models, with narrower LoA, stronger ICC and smaller ES for both the RR intervals and HRV parameters. The findings support the validity of the Polar V800 and its ability to produce RR interval recordings consistent with an ECG. In addition, HRV parameters derived from these recordings are also highly comparable

The unusual electronic structure of the "pseudo-ladder" compound CaCu2O3

Experimental and theoretical studies of the unoccupied electronic structure of CaCu2O3 single crystals have been performed using polarization-dependent x-ray absorption spectroscopy and band structure calculations. The measured hole distribution shows an unusual large number of holes in orbitals parallel to the interlayer direction which is in agreement with the theoretical analysis. CaCu2O3 deviates significantly from the standard pd-sigma cuprate picture. The corresponding strong interlayer exchange is responsible for the missing spin gap generic for other two-leg ladder cuprates.Comment: 4 pages, 3 figures include

Studies of colossal magnetoresistive oxides with radioactive isotopes

We propose to study Colossal Magnetoresistive (CMR) oxides with several nuclear techniques, which use radioactive elements at ISOLDE. Our aim is to provide local and element selective information on some of the doping mechanisms that rule electronic interactions and magnetoresistance, in a complementary way to the use of conventional characterisation techniques. Three main topics are proposed: \\ \\ a) Studies of local [charge and] structural modifications in antiferromagnetic LaMnO$_{3+ \delta}$ and La$_{1-x}$R$_{x}$MnO$_{3}$ with R=Ca and Cd, doped ferromagnetic systems with competing interactions: - research on the lattice site and electronic characterisation of the doping element. \\ \\ b) Studies of self doped La$_{x}$R$_{1-x}$MnO$_{3+\delta}$ systems, with oxygen and cation non-stoichiometry: -learning the role of defects in the optimisation of magnetoresistive properties. \\ \\ c) Probing the disorder and quenched random field effects in the vicinity of the charge or orbital Ordered/Ferromagnetic phase instability: - Investigating the local environment of ions at the Mn site, which trigger the ferromagnetic phase. Our approach to study these problems, combines complementary techniques such as Perturbed Angular Correlation, Emission Channeling and Electrical/Magnetic Measurements in pellets, single crystals and high quality thin films of CMR oxides doped with radioactive isotopes. Preliminary results obtained in La Cd MnO$_{3+x}$ pellets and thin films implanted with $^{111m}$Cd are also presented

Structure of metal site in azurin, met 121 mutants of azurin, and stellacyanin investigated by 111m Cd Perturbed Angular Correlation (PAC)

The geometries of the metal sites in cadmium-substituted azurins have been investigated by Cd-111m perturbed angular correlation (PAC), The study includes wild type azurin as well as Met(121) mutants of azurin, where methionine has been substituted by Ala, Asn, Asp, Gin, Glu, and Leu.The nuclear quadrupole interaction of wild type azurin analyzed in the angular overlap model is well described as coordination of His(46), His(117), and Cys(112) and cannot be described by coordination of Met(121) and/or Gly(45).For most of the mutants, there exist two coordination geometries of the cadmium ion, With the exception of the Gau and Asp mutants, one of the conformations is similar to the wild type conformation. The other coordination geometries are either best described by a coordinating water molecule close to the original methionine position or by coordination by the substituting amino acid, These experiments show that even though the methionine does not coordinate it plays an important role for the geometry of the metal site.The nuclear quadrupole interaction of stellacyanin was also measured, The value resembles the most prominent nuclear quadrupole interaction of the Met(121) --> Gin mutant of Alcaligenes denitrificans azurin, indicating that the structures of the two metal sites are similar.Macromolecular Biochemistr

Differential View on the Bile Acid Stress Response of Clostridioides difficile

Clostridioides difficile is an intestinal human pathogen that uses the opportunity of a depleted microbiota to cause an infection. It is known, that the composition of the intestinal bile acid cocktail has a great impact on the susceptibility toward a C. difficile infection. However, the specific response of growing C. difficile cells to diverse bile acids on the molecular level has not been described yet. In this study, we recorded proteome signatures of shock and long-term (LT) stress with the four main bile acids cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), and lithocholic acid (LCA). A general overlapping response to all tested bile acids could be determined particularly in shock experiments which appears plausible in the light of their common steroid structure. However, during LT stress several proteins showed an altered abundance in the presence of only a single or a few of the bile acids indicating the existence of specific adaptation mechanisms. Our results point at a differential induction of the groEL and dnaKJgrpE chaperone systems, both belonging to the class I heat shock genes. Additionally, central metabolic pathways involving butyrate fermentation and the reductive Stickland fermentation of leucine were effected, although CA caused a proteome signature different from the other three bile acids. Furthermore, quantitative proteomics revealed a loss of flagellar proteins in LT stress with LCA. The absence of flagella could be substantiated by electron microscopy which also indicated less flagellated cells in the presence of DCA and CDCA and no influence on flagella formation by CA. Our data break down the bile acid stress response of C. difficile into a general and a specific adaptation. The latter cannot simply be divided into a response to primary and secondary bile acids, but rather reflects a complex and variable adaptation process enabling C. difficile to survive and to cause an infection in the intestinal tract

Copper-dependent activation of hypoxia-inducible factor (HIF)-1: implications for ceruloplasmin regulation

Cellular oxygen partial pressure is sensed by a family of prolyl-4-hydroxylase domain (PHD) enzymes that modify hypoxia-inducible factor (HIF)alpha subunits. Upon hydroxylation under normoxic conditions, HIFalpha is bound by the von Hippel-Lindau tumor suppressor protein and targeted for proteasomal destruction. Since PHD activity is dependent on oxygen and ferrous iron, HIF-1 mediates not only oxygen- but also iron-regulated transcriptional gene expression. Here we show that copper (CuCl(2)) stabilizes nuclear HIF-1alpha under normoxic conditions, resulting in hypoxia-response element (HRE)-dependent reporter gene expression. In in vitro hydroxylation assays CuCl(2) inhibited prolyl-4-hydroxylation independently of the iron concentration. Ceruloplasmin, the main copper transport protein in the plasma and a known HIF-1 target in vitro, was also induced in vivo in the liver of hypoxic mice. Both hypoxia and CuCl(2) increased ceruloplasmin (as well as vascular endothelial growth factor [VEGF] and glucose transporter 1 [Glut-1]) mRNA levels in hepatoma cells, which was due to transcriptional induction of the ceruloplasmin gene (CP) promoter. In conclusion, our data suggest that PHD/HIF/HRE-dependent gene regulation can serve as a sensory system not only for oxygen and iron but also for copper metabolism, regulating the oxygen-, iron- and copper-binding transport proteins hemoglobin, transferrin, and ceruloplasmin, respectively

Iscador Qu inhibits doxorubicin-induced senescence of MCF7 cells

Chemotherapy in patients with inoperable or advanced breast cancer inevitably results in low-dose exposure of tumor-cell subset and senescence. Metabolically active senescent cells secrete multiple tumor promoting factors making their elimination a therapeutic priority. Viscum album is one of the most widely used alternative anti-cancer medicines facilitating chemotherapy tolerance of breast cancer patients. The aim of this study was to model and investigate how Viscum album extracts execute additive anti-tumor activity with low-dose Dox using ER + MCF7 breast cancer cells. We report that cotreatment of MCF7 with Viscum album and Dox abrogates G2/M cycle arrest replacing senescence with intrinsic apoptotic program. Mechanistically, this switch was associated with down-regulation of p21, p53/p73 as well as Erk1/2 and p38 activation. Our findings, therefore, identify a novel mechanistic axis of additive antitumor activity of Viscum album and low dose-Dox. In conclusion, ER + breast cancer patients may benefit from addition of Viscum album to low-dose Dox chemotherapy due to suppression of cancer cell senescence and induction of apoptosis