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191.
Silke Andrich Burkhard Haastert Elke Neuhaus Kathrin Neidert Werner Arend Christian Ohmann Jürgen Grebe Andreas Vogt Pascal Jungbluth Grit R?sler Joachim Windolf Andrea Icks 《PloS one》2015,10(9)
Epidemiological data about pelvic fractures are limited. Until today, most studies only analyzed inpatient data. The purpose of this study was to estimate incidence rates of pelvic fractures in the German population aged 60 years or older, based on outpatient and inpatient data. We conducted a retrospective population-based observational study based on routine data from a large health insurance company in Germany. Age and sex-specific incidence rates of first fractures between 2008 and 2011 were calculated. We also standardized incidence rates with respect to age and sex in the German population. Multiple Poisson regression models were used to evaluate the association between the risk of first pelvic fracture as outcome and sex, age, calendar year and region as independent variables. The total number of patients with a first pelvic fracture corresponded to 8,041 and during the study period 5,978 insured persons needed inpatient treatment. Overall, the standardized incidence rate of all first pelvic fractures was 22.4 [95% CI 22.0–22.9] per 10,000 person-years, and the standardized incidence rate of inpatient treated fractures 16.5 [16.1–16.9]. Our adjusted regression analysis confirmed a significant sex (RR 2.38 [2.23–2.55], p < 0.001, men as reference) and age effect (higher risk with increasing age, p < 0.001) on first fracture risk. We found a slight association between calendar year (higher risk in later years compared to 2008, p = 0.0162) and first fracture risk and a further significant association with region (RR 0.92 [0.87–0.98], p = 0.006, Westfalen-Lippe as reference). The observed incidences are considerably higher than incidences described in the international literature, even if only inpatient treated pelvic fractures are regarded. Besides which, non-inclusion of outpatient data means that a relevant proportion of pelvic fractures are not taken into account. Prevention of low energy trauma among older people remains an important issue. 相似文献
192.
Roland Benz Michael D. Jones Farhan Younas Elke Maier Niraj Modi Reinhard Mentele Friedrich Lottspeich Ulrich Kleinekath?fer John Smit 《PloS one》2015,10(11)
Caulobacter crescentus is an oligotrophic bacterium that lives in dilute organic environments such as soil and freshwater. This bacterium represents an interesting model for cellular differentiation and regulation because daughter cells after division have different forms: one is motile while the other is non-motile and can adhere to surfaces. Interestingly, the known genome of C. crescentus does not contain genes predicted to code for outer membrane porins of the OmpF/C general diffusion type present in enteric bacteria or those coding for specific porins selective for classes of substrates. Instead, genes coding for 67 TonB-dependent outer membrane receptors have been identified, suggesting that active transport of specific nutrients may be the norm. Here, we report that high channel-forming activity was observed with crude outer membrane extracts of C. crescentus in lipid bilayer experiments, indicating that the outer membrane of C. crescentus contained an ion-permeable channel with a single-channel conductance of about 120 pS in 1M KCl. The channel-forming protein with an apparent molecular mass of about 20 kDa was purified to homogeneity. Partial protein sequencing of the protein indicated it was a member of the OmpW family of outer membrane proteins from Gram-negative bacteria. This channel was not observed in reconstitution experiments with crude outer membrane extracts of an OmpW deficient C. crescentus mutant. Biophysical analysis of the C. crescentus OmpW suggested that it has features that are special for general diffusion porins of Gram-negative outer membranes because it was not a wide aqueous channel. Furthermore, OmpW of C. crescentus seems to be different to known OmpW porins and has a preference for ions, in particular cations. A putative model for OmpW of C. crescentus was built on the basis of the known 3D-structures of OmpW of Escherichia coli and OprG of Pseudomonas aeruginosa using homology modeling. A comparison of the two known structures with the model of OmpW of C. crescentus suggested that it has a more hydrophilic interior and possibly a larger diameter. 相似文献
193.
Devy Widjaja Alessandro Montalto Elke Vlemincx Daniele Marinazzo Sabine Van Huffel Luca Faes 《PloS one》2015,10(6)
An analysis of cardiorespiratory dynamics during mental arithmetic, which induces stress, and sustained attention was conducted using information theory. The information storage and internal information of heart rate variability (HRV) were determined respectively as the self-entropy of the tachogram, and the self-entropy of the tachogram conditioned to the knowledge of respiration. The information transfer and cross information from respiration to HRV were assessed as the transfer and cross-entropy, both measures of cardiorespiratory coupling. These information-theoretic measures identified significant nonlinearities in the cardiorespiratory time series. Additionally, it was shown that, although mental stress is related to a reduction in vagal activity, no difference in cardiorespiratory coupling was found when several mental states (rest, mental stress, sustained attention) are compared. However, the self-entropy of HRV conditioned to respiration was very informative to study the predictability of RR interval series during mental tasks, and showed higher predictability during mental arithmetic compared to sustained attention or rest. 相似文献
194.
G. Emerens Wensink Annelot F. Schoffelen Hugo A. Tempelman Maarten B. Rookmaaker Andy I. M. Hoepelman Roos E. Barth 《PloS one》2015,10(8)
Context
As life expectancy improves among Human Immunodeficiency Virus (HIV) patients, renal and cardiovascular diseases are increasingly prevalent in this population. Renal and cardiovascular disease are mutual risk factors and are characterized by albuminuria. Understanding the interactions between HIV, cardiovascular risk factors and renal disease is the first step in tackling this new therapeutic frontier in HIV.Methods
In a rural primary health care centre, 903 HIV-infected adult patients were randomly selected and data on HIV-infection and cardiovascular risk factors were collected. Glomerular filtration rate (eGFR) was estimated. Albuminuria was defined as an Albumin-Creatinine-Ratio above 30 mg/g. Multivariate logistic regression analysis was used to analyse albuminuria and demographic, clinical and HIV-associated variables.Results
The study population consisted of 903 HIV-infected patients, with a median age of 40 years (Inter-Quartile Range (IQR) 34–48 years), and included 625 (69%) women. The median duration since HIV diagnosis was 26 months (IQR 12–58 months) and 787 (87%) received antiretroviral therapy. Thirty-six (4%) of the subjects were shown to have diabetes and 205 (23%) hypertension. In the cohort, 21% had albuminuria and 2% an eGFR <60 mL/min/1.73m2. Albuminuria was associated with hypertension (adjusted odds ratio (aOR) 1.59; 95% confidence interval (CI) 1.05–2.41; p<0.05), total cholesterol (aOR 1.31; 95% CI 1.11–1.54; p<0.05), eGFR (aOR 0.98; 95% CI 0.97–0.99; p<0.001) and detectable viral load (aOR 2.74; 95% CI 1.56–4.79; p<0.001). Hypertension was undertreated: 78% were not receiving treatment, while another 11% were inadequately treated. No patients were receiving lipid-lowering medication.Conclusion
Glomerular filtration rate was well conserved, while albuminuria was common amongst HIV-infected patients in rural South Africa. Both cardiovascular and HIV-specific variables were associated with albuminuria. Improved cardiovascular risk prevention as well as adequate virus suppression might be the key to escape the vicious circle of renal failure and cardiovascular disease and improve the long-term prognosis of HIV-infected patients. 相似文献195.
Katja Schmitz Hartmut Koeppen Elke Binot Jana Fassunke Helen Künstlinger Michaela A. Ihle Carina Heydt Eva Wardelmann Reinhard Büttner Sabine Merkelbach-Bruse Josef Rüschoff Hans-Ulrich Schildhaus 《PloS one》2015,10(4)
Soft tissue sarcomas are a heterogeneous group of tumors with many different subtypes. In 2014 an estimated 12,020 newly diagnosed cases and 4,740 soft tissue sarcoma related deaths can be expected in the United States. Many soft tissue sarcomas are associated with poor prognosis and therapeutic options are often limited. The evolution of precision medicine has not yet fully reached the clinical treatment of sarcomas since therapeutically tractable genetic changes have not been comprehensively studied so far. We analyzed a total of 484 adult-type malignant mesenchymal tumors by MET fluorescence in situ hybridization and MET and hepatocyte growth factor immunohistochemistry. Eleven different entities were included, among them the most common and clinically relevant subtypes and tumors with specific translocations or complex genetic changes. MET protein expression was observed in 2.6% of the cases, all of which were either undifferentiated pleomorphic sarcomas or angiosarcomas, showing positivity rates of 14% and 17%, respectively. 6% of the tumors showed hepatocyte growth factor overexpression, mainly seen in undifferentiated pleomorphic sarcomas and angiosarcomas, but also in clear cell sarcomas, malignant peripheral nerve sheath tumors, leiomyosarcomas and gastrointestinal stromal tumors. MET and hepatocyte growth factor overexpression were significantly correlated and may suggest an autocrine activation in these tumors. MET FISH amplification and copy number gain were present in 4% of the tumors (15/413). Two samples, both undifferentiated pleomorphic sarcomas, fulfilled the criteria for high level amplification of MET, one undifferentiated pleomorphic sarcoma reached an intermediate level copy number gain, and 12 samples of different subtypes were categorized as low level copy number gains for MET. Our findings indicate that angiosarcomas and undifferentiated pleomorphic sarcomas rather than other frequent adult-type sarcomas should be enrolled in screening programs for clinical trials with MET inhibitors. The screening methods should include both in situ hybridization and immunohistochemistry. 相似文献
196.
Leo T. H. Tang Meera Trivedi Jenna Freund Christopher J. Salazar Maisha Rahman Nelson J. Ramirez-Suarez Garrett Lee Yu Wang Barth D. Grant Hannes E. Bülow 《PLoS genetics》2021,17(7)
The assembly of neuronal circuits involves the migrations of neurons from their place of birth to their final location in the nervous system, as well as the coordinated growth and patterning of axons and dendrites. In screens for genes required for patterning of the nervous system, we identified the catp-8/P5A-ATPase as an important regulator of neural patterning. P5A-ATPases are part of the P-type ATPases, a family of proteins known to serve a conserved function as transporters of ions, lipids and polyamines in unicellular eukaryotes, plants, and humans. While the function of many P-type ATPases is relatively well understood, the function of P5A-ATPases in metazoans remained elusive. We show here, that the Caenorhabditis elegans ortholog catp-8/P5A-ATPase is required for defined aspects of nervous system development. Specifically, the catp-8/P5A-ATPase serves functions in shaping the elaborately sculpted dendritic trees of somatosensory PVD neurons. Moreover, catp-8/P5A-ATPase is required for axonal guidance and repulsion at the midline, as well as embryonic and postembryonic neuronal migrations. Interestingly, not all axons at the midline require catp-8/P5A-ATPase, although the axons run in the same fascicles and navigate the same space. Similarly, not all neuronal migrations require catp-8/P5A-ATPase. A CATP-8/P5A-ATPase reporter is localized to the ER in most, if not all, tissues and catp-8/P5A-ATPase can function both cell-autonomously and non-autonomously to regulate neuronal development. Genetic analyses establish that catp-8/P5A-ATPase can function in multiple pathways, including the Menorin pathway, previously shown to control dendritic patterning in PVD, and Wnt signaling, which functions to control neuronal migrations. Lastly, we show that catp-8/P5A-ATPase is required for localizing select transmembrane proteins necessary for dendrite morphogenesis. Collectively, our studies suggest that catp-8/P5A-ATPase serves diverse, yet specific, roles in different genetic pathways and may be involved in the regulation or localization of transmembrane and secreted proteins to specific subcellular compartments. 相似文献
197.
Srikanth Perike Nurdan Özkucur Priyanka Sharma Wolfgang Staroske Robert Bläsche Kathrin Barth Richard HW Funk 《Experimental cell research》2014
The Na(+)/H(+) exchanger NHE3 colocalizes with beta-actin at the leading edge of directionally migrating cells. Using human osteosarcoma cells (SaOS-2), rat osteoblasts (calvaria), and human embryonic kidney (HEK) cells, we identified a novel role for NHE3 via beta-actin in anode and cathode directed motility, during electrotaxis. NHE3 knockdown by RNAi revealed that NHE3 expression is required to achieve constant directionality and polarity in migrating cells. Phosphorylated NHE3 (pNHE3) and beta-actin complex formation was impaired by the NHE3 inhibitor S3226 (IC50 0.02 µM). Fluorescence cross-correlation spectroscopy (FCCS) revealed that the molecular interactions between NHE3 and beta-actin in membrane protrusions increased 1.7-fold in the presence of a directional cue and decreased 3.3-fold in the presence of cytochalasin D. Data from flow cytometric analysis showed that membrane potential of cells (Vmem) decreases in directionally migrating, NHE3-deficient osteoblasts and osteosarcoma cells whereas only Vmem of wild type osteoblasts is affected during directional migration. These findings suggest that pNHE3 has a mechanical function via beta-actin that is dependent on its physiological activity and Vmem. Furthermore, phosphatidylinositol 3,4,5-trisphosphate (PIP3) levels increase while PIP2 remains stable when cells have persistent directionality. Both PI3 kinase (PI3K) and Akt expression levels change proportionally to NHE3 levels. Interestingly, however, the content of pNHE3 level does not change when PI3K/Akt is inhibited. Therefore, we conclude that NHE3 can act as a direction sensor for cells and that NHE3 phosphorylation in persistent directional cell migration does not involve PI3K/Akt during electrotaxis. 相似文献
198.
Elke Genersch 《Applied microbiology and biotechnology》2010,87(1):87-97
Managed honey bees are the most important commercial pollinators of those crops which depend on animal pollination for reproduction
and which account for 35% of the global food production. Hence, they are vital for an economic, sustainable agriculture and
for food security. In addition, honey bees also pollinate a variety of wild flowers and, therefore, contribute to the biodiversity
of many ecosystems. Honey and other hive products are, at least economically and ecologically rather, by-products of beekeeping.
Due to this outstanding role of honey bees, severe and inexplicable honey bee colony losses, which have been reported recently
to be steadily increasing, have attracted much attention and stimulated many research activities. Although the phenomenon
“decline of honey bees” is far from being finally solved, consensus exists that pests and pathogens are the single most important
cause of otherwise inexplicable colony losses. This review will focus on selected bee pathogens and parasites which have been
demonstrated to be involved in colony losses in different regions of the world and which, therefore, are considered current
threats to honey bees and beekeeping. 相似文献
199.
Annett Mikolasch Veronika Hahn Katrin Manda Judith Pump Nicole Illas Dirk Gördes Michael Lalk Manuela Gesell Salazar Elke Hammer Wolf-Dieter Jülich Stephan Rawer Kerstin Thurow Ulrike Lindequist Frieder Schauer 《Amino acids》2010,39(3):671-683
In order to design potential biomaterials, we investigated the laccase-catalyzed cross-linking between l-lysine or lysine-containing peptides and dihydroxylated aromatics. l-Lysine is one of the major components of naturally occurring mussel adhesive proteins (MAPs). Dihydroxylated aromatics are structurally related to 3,4-dihydroxyphenyl-l-alanine, another main component of MAPs. Mass spectrometry and nuclear magnetic resonance analyses show that the ε-amino group of l-lysine is able to cross-link dihydroxylated aromatics. Additional oligomer and polymer cross-linked products were obtained from di- and oligopeptides containing l-lysine. Potential applications in medicine or industry for biomaterials synthesised via the three component system consisting of the oligopeptide [Tyr-Lys]10, dihydroxylated aromatics and laccase are discussed. 相似文献
200.
Vassili Valayannopoulos Coralie Haudry Valérie Serre Magalie Barth Nathalie Boddaert Jean-Baptiste Arnoux Valérie Cormier-Daire Marlène Rio Daniel Rabier Anne Vassault Arnold Munnich Jean-Paul Bonnefont Pascale de Lonlay Agnès Rötig Anne-Sophie Lebre 《Mitochondrion》2010,10(4):335-341
Deficiencies in two subunits of the succinyl-coenzyme A synthetase (SCS) have been involved in patients with encephalomyopathy and mild methylmalonic aciduria (MMA). In this study, we described three new SUCLG1 patients and performed a meta-analysis of the literature. Our report enlarges the phenotypic spectrum of SUCLG1 mutations and confirms that a characteristic metabolic profile (presence of MMA and C4-DC carnitine in urines) and basal ganglia MRI lesions are the hallmarks of SCS defects. As mitochondrial DNA depletion in muscle is not a constant finding in SUCLG1 patients, this may suggest that diagnosis should not be based on it, but also that alternative physiopathological mechanisms may be considered to explain the combined respiratory chain deficiency observed in SCS patients. 相似文献