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Beier F, Hupel C, Kuhn S, Hein S, Nold J, Proske F, Sattler B, Liem A, Jauregui C, Limpert J, Haarlammert N, Schreiber T, Eberhardt R, Tünnermann A. Single mode 4.3 kW output power from a diode-pumped Yb-doped fiber amplifier. OPTICS EXPRESS 2017; 25:14892-14899. [PMID: 28789071 DOI: 10.1364/oe.25.014892] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2017] [Accepted: 05/22/2017] [Indexed: 06/07/2023]
Abstract
We investigate the average power scaling of two diode-pumped Yb-doped fiber amplifiers emitting a diffraction-limited beam. The first fiber under investigation with a core diameter of 30 µm was able to amplify a 10 W narrow linewidth seed laser up to 2.8 kW average output power before the onset of transverse mode instabilities (TMI). A further power scaling was achieved using a second fiber with a smaller core size (23µm), which allowed for a narrow linewidth output power of 3.5 kW limited by stimulated Brillouin scattering (SBS). We mitigated SBS using a spectral broadening mechanism, which allowed us to further increase the output power to 4.3 kW only limited by the available pump power. Up to this power level, a high slope efficiency of 90% with diffraction-limited beam quality and without any sign of TMI or stimulated Raman scattering for a spectral dynamic range of higher than -80 dB was obtained.
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Karlas T, Weise L, Kuhn S, Krenzien F, Mehdorn M, Petroff D, Linder N, Schaudinn A, Busse H, Keim V, Pratschke J, Wiegand J, Splith K, Schmelzle M. Correlation of cell-free DNA plasma concentration with severity of non-alcoholic fatty liver disease. J Transl Med 2017; 15:106. [PMID: 28521774 PMCID: PMC5437653 DOI: 10.1186/s12967-017-1208-6] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2017] [Accepted: 05/04/2017] [Indexed: 12/16/2022] Open
Abstract
BACKGROUND The assessment of fibrosis and inflammatory activity is essential to identify patients with non-alcoholic fatty liver disease (NAFLD) at risk for progressive disease. Serum markers and ultrasound-based methods can replace liver biopsy for fibrosis staging, whereas non-invasive characterization of inflammatory activity remains a clinical challenge. Cell-free DNA (cfDNA) is a novel non-invasive biomarker for assessing cellular inflammation and cell death, which has not been evaluated in NAFLD. METHODS Patients and healthy controls from two previous studies were included. NAFLD disease activity and severity were non-invasively characterized by liver stiffness measurement (transient elastography, TE) including steatosis assessment with controlled attenuation parameter (CAP), single-proton magnetic resonance spectroscopy (1H-MRS) for determination of hepatic fat fraction, aminotransferases and serum ferritin. cfDNA levels (90 and 222 bp fragments) were analyzed using quantitative real-time PCR. RESULTS Fifty-eight NAFLD patients (age 62 ± 11 years, BMI 28.2 ± 3.5 kg/m2) and 13 healthy controls (age 38 ± 12 years, BMI 22.4 ± 2.1 kg/m2) were included. 90 bp cfDNA levels were significantly higher in NAFLD patients compared to healthy controls: 3.7 (1.3-23.1) vs. 2.9 (1.4-4.1) ng/mL (p = 0.014). In the NAFLD cohort, circulating cfDNA correlated significantly with disease activity and severity, especially in patients with elevated liver stiffness (n = 13, 22%) compared to cases with TE values ≤7 kPa: cf90 bp 6.05 (2.41-23.13) vs. 3.16 (1.29-7.31) ng/mL (p < 0.001), and cf222 bp 14.41 (9.27-22.90) vs. 11.32 (6.05-18.28) ng/mL (p = 0.0041). CONCLUSIONS Cell-free DNA plasma concentration correlates with established non-invasive markers of NAFLD activity and severity. Therefore, cfDNA should be further evaluated as biomarker for identifying patients at risk for progressive NAFLD.
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Schütze N, Trojandt S, Kuhn S, Tomm JM, von Bergen M, Simon JC, Polte T. Allergen-Induced IL-6 Regulates IL-9/IL-17A Balance in CD4+ T Cells in Allergic Airway Inflammation. THE JOURNAL OF IMMUNOLOGY 2016; 197:2653-64. [PMID: 27574298 DOI: 10.4049/jimmunol.1501599] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Received: 07/20/2015] [Accepted: 08/02/2016] [Indexed: 12/21/2022]
Abstract
IL-9-secreting Th9 cells have been considered to play a pivotal role in the pathogenesis of atopic diseases. To what extent IL-9-producing cells are induced or regulated by sensitization with naturally occurring allergens is not yet clear. Naturally occurring allergens are capable of inducing IL-6 production in dendritic cells (DCs). Whether allergen-induced IL-6 supports a Th9 subtype by increasing IL-9 production, as observed in in vitro studies, or rather favors Th17 differentiation is not finally resolved. Therefore, in the present study we have investigated the impact of IL-6 on the Th9/Th17 balance depending on the predominant cytokine milieu and, additionally, in vivo using a DC-driven murine asthma model. In vitro, IL-6 increases Th9 cells under strong IL-4 and TGF-β activation, whereas under moderate IL-4 and TGF-β activation the presence of IL-6 shifts naive CD4(+) cells to Th17 cells. To induce allergic airway inflammation, OVA-pulsed DCs from IL-6-deficient or wild-type donors were adoptively transferred into BALB/c mice. Recipients receiving IL-6-producing wild-type DCs showed a significant decrease of Th9- and IL-4-producing Th2 cells but an increase of Th17 cells in lung tissue in comparison with recipients sensitized with IL-6-deficient DCs. Our data suggest that the IL-6-mediated reduction of Th2-related IL-4 leads to a decline of the Th9 immune response and allows Th17 differentiation.
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Pridjian G, Sirois PA, McRae S, Hinckley AF, Rasmussen SA, Kissinger P, Buekens P, Hayes EB, O’Leary D, Kuhn S, Swan KF, Xiong X, Wesson DM. Prospective study of pregnancy and newborn outcomes in mothers with West nile illness during pregnancy. BIRTH DEFECTS RESEARCH. PART A, CLINICAL AND MOLECULAR TERATOLOGY 2016; 106:716-23. [PMID: 27223334 PMCID: PMC5008687 DOI: 10.1002/bdra.23523] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 04/11/2016] [Accepted: 04/20/2016] [Indexed: 11/09/2022]
Abstract
BACKGROUND A previous case report of West Nile virus (WNV) illness during pregnancy suggested that WNV could be a cause of congenital defects. We performed a prospective, longitudinal cohort study of pregnant women with WNV illness to increase our knowledge of the effects of WNV illness during pregnancy. METHODS Participants were enrolled in 2005 to 2008 from pregnant women with serologically confirmed WNV illness reported to the Centers for Disease Control and Prevention. Comparison was made to WNV-uninfected women, matched on maternal age and enrollment month. Pregnancy and newborn data were collected; cord blood WNV serology was obtained. Pediatric exams and the Bayley Scales of Infant and Toddler Development-Third Edition (Bayley-III) were performed. RESULTS Twenty-eight WNV-infected mothers and 25 WNV-uninfected mothers participated. Maternal demographics were similar except for a higher rate of planned pregnancies, education, and household income in the WNV-uninfected mothers. There were no differences in pregnancy and delivery characteristics except that infected mothers had a higher incidence of febrile illnesses and used more medications. Birth weight, length, head circumference, and rate of congenital malformations were similar in babies born to WNV-infected and -uninfected mothers. Follow-up physical exams were generally normal. The Bayley-III assessments, available for 17 children born to mothers with WNV illness, showed performance at or above age level across domains. CONCLUSION The risk for adverse pregnancy and newborn outcomes in women experiencing WNV illness in pregnancy appears to be low, but future studies with larger numbers are needed to rule out a small risk. Birth Defects Research (Part A) 106:716-723, 2016. © 2016 Wiley Periodicals, Inc.
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Kreitner KF, Kuhn S. Muss das CT immer im Schockraum integriert sein? Das Mainzer Modell. ROFO-FORTSCHR RONTG 2016. [DOI: 10.1055/s-0036-1581753] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Beier F, Hupel C, Nold J, Kuhn S, Hein S, Ihring J, Sattler B, Haarlammert N, Schreiber T, Eberhardt R, Tünnermann A. Narrow linewidth, single mode 3 kW average power from a directly diode pumped ytterbium-doped low NA fiber amplifier. OPTICS EXPRESS 2016; 24:6011-6020. [PMID: 27136795 DOI: 10.1364/oe.24.006011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report on a newly designed and fabricated ytterbium-doped large mode area fiber with an extremely low NA (~0.04) and related systematic investigations on fiber parameters that crucially influence the mode instability threshold. The fiber is used to demonstrate a narrow linewidth, continuous wave, single mode fiber laser amplifier emitting a maximum output power of 3 kW at a wavelength of 1070 nm without reaching the mode-instability threshold. A high slope efficiency of 90 %, excellent beam quality, high temporal stability, and an ASE suppression of 70 dB could be reached with a signal linewidth of only 170 pm.
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Tsatrafyllis N, Bergues B, Schröder H, Veisz L, Skantzakis E, Gray D, Bodi B, Kuhn S, Tsakiris GD, Charalambidis D, Tzallas P. The ion microscope as a tool for quantitative measurements in the extreme ultraviolet. Sci Rep 2016; 6:21556. [PMID: 26868370 PMCID: PMC4751500 DOI: 10.1038/srep21556] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2015] [Accepted: 01/22/2016] [Indexed: 11/16/2022] Open
Abstract
We demonstrate a tool for quantitative measurements in the extreme ultraviolet (EUV) spectral region measuring spatially resolved atomic ionization products at the focus of an EUV beam. The ionizing radiation is a comb of the 11(th)-15(th) harmonics of a Ti:Sapphire femtosecond laser beam produced in a Xenon gas jet. The spatial ion distribution at the focus of the harmonics is recorded using an ion microscope. Spatially resolved single- and two-photon ionization products of Argon and Helium are observed. From such ion distributions single- and two-photon generalized cross sections can be extracted by a self-calibrating method. The observation of spatially resolved two-EUV-photon ionization constitutes an initial step towards future single-shot temporal characterization of attosecond pulses.
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Greenfield JRF, Kuhn S, Mehler D, Puel F, Rommens PM. Biomechanical evaluation of a new treatment method for distal tibia fractures. Comput Methods Biomech Biomed Engin 2015; 18 Suppl 1:1952-3. [DOI: 10.1080/10255842.2015.1069582] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Schmidt CS, Schulte B, Seo H, Kuhn S, O'Donnell A, Kriston L, Verthein U, Reimer J. Meta-analysis on the Effectiveness of Alcohol Screening and Brief Interventions for Patients in Emergency Care Settings. SUCHTTHERAPIE 2015. [DOI: 10.1055/s-0035-1557664] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kuhn S, Verthein U, Holzbach R, Dirmaier J, Mokhar A. Benzodiazepine und Z-Substanzen – Einnahmeverhalten und Motive bei älteren Menschen. SUCHTTHERAPIE 2015. [DOI: 10.1055/s-0035-1557552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Kuhn S, Appelmann P, Pairon P, Gruszka D, Rommens PM. Retrograde tibial nail: anatomical implantation and surgical feasibility study. ACTA CHIRURGIAE ORTHOPAEDICAE ET TRAUMATOLOGIAE CECHOSLOVACA 2015; 82:203-208. [PMID: 26317291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
PURPOSE OF THE STUDY The treatment of distal tibial fractures requires a stable fixation while minimizing the secondary trauma to the soft tissues by the surgical approach and implant. The experimental Retrograde Tibial Nail is currently investigated as a minimally invasive alternative to plating and antegrade nailing. The purpose of this study was to evaluate the surgical feasibility in a cadaver model for all distal tibial fracture types generally considered treatable by nailing. MATERIAL AND METHODS Five different fracture types (AO/OTA 43-A1/A2/A3 and 43-C1/C2) were created on separate cadaveric limbs. In simple fractures (AO/OTA 43-A1/A2/A3) primary nailing was performed. In intraarticular fractures (AO/OTA 43-C1/2) reduction of the articular block and lag screw fixation was performed before nailing. Intraoperative complications, quality of reduction, fluoroscopy duration and operative time were evaluated. RESULTS Retrograde intramedullary nailing is feasible in simple fracture types by closed manual reduction and percutaneous reduction forceps. Retrograde nailing is possible in fractures with simple intraarticular involvement after primary lag screw fixation. The duration of surgery averaged 51.8 minutes (range 40-62 min). No major complications occurred during nailing. CONCLUSIONS The minimally invasive retrograde nail combines a minimally invasive local osteosynthesis with the ability to adequately fix extraarticular and simple intraarticular distal tibial fractures. The results suggests that retrograde tibia nailing is a promising new concept for the treatment of distal tibia fractures. Key words: minimally invasive surgery, tibia, metaphyseal fractures, intramedullary nailing, retrograde nailing.
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Kuhn S, Knirsch M, Rüttiger L, Kasperek S, Winter H, Freichel M, Flockerzi V, Knipper M, Engel J. Ba2+currents in inner and outer hair cells of mice lacking the voltage-dependent Ca2+channel subunits β3 or β4. Channels (Austin) 2014; 3:366-76. [DOI: 10.4161/chan.3.5.9774] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Pairon P, Ossendorf C, Kuhn S, Hofmann A, Rommens PM. Intramedullary nailing after external fixation of the femur and tibia: a review of advantages and limits. Eur J Trauma Emerg Surg 2014; 41:25-38. [PMID: 26038163 DOI: 10.1007/s00068-014-0448-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2014] [Accepted: 09/08/2014] [Indexed: 10/24/2022]
Abstract
PURPOSE AND METHODS External fixation is a safe option for stabilisation of extremity lesions in the polytraumatised patient as well as in fractures with severe soft tissue damage. Nevertheless, long-term-complications are to be expected when external fixation is chosen as a definitive treatment. The purpose of this review article is twofold: primarily, to define the rationale of a procedural change from an external fixator to an intramedullary nail; secondarily, to assess the possible advantages and pitfalls of a single- or two-staged procedure. RESULTS AND CONCLUSIONS External fixation of the femur is recommended in multiply injured patients who are critically ill to avoid an additional inflammatory response caused by the surgical trauma of primary nailing. The conversion towards nailing must be done as soon as the clinical condition of the patient has been stabilised. Stable polytraumatised patients do not benefit from initial stabilisation with an external fixator and should immediately be treated with a definitive osteosynthesis. In tibial fractures, external fixation followed by intramedullary nailing is recommendable in fractures with severe soft tissue injuries. Conversion should be done as soon as the soft tissues allow before pin-tract infections occur and performed in a one-staged procedure.
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Boggild AK, Geduld J, Libman M, Ward BJ, McCarthy A, Hajek J, Ghesquiere W, Vincelette J, Kuhn S, Freedman DO, Kain KC. Travel-acquired infections in Canada: CanTravNet 2011-2012. CANADA COMMUNICABLE DISEASE REPORT = RELEVE DES MALADIES TRANSMISSIBLES AU CANADA 2014; 40:313-325. [PMID: 29769859 PMCID: PMC5864452 DOI: 10.14745/ccdr.v40i16a01] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Important gaps remain in our knowledge of the infectious diseases people acquire while travelling and the impact of pathogens imported by Canadian travellers. OBJECTIVE To provide a surveillance update of illness in a cohort of returned Canadian travellers and new immigrants. METHODS Data on returning Canadian travellers and new immigrants presenting to a CanTravNet site between September 2011 and September 2012 were extracted and analyzed by destination, presenting symptoms, common and emerging infectious diseases and disease severity. RESULTS During the study period, 2283 travellers and immigrants presented to a CanTravNet site, 88% (N=2004) of whom were assigned a travel-related diagnosis. Top three destinations for non-immigrant travellers were India (N=132), Mexico (N=103) and Cuba (N=89). Fifty-one cases of malaria were imported by ill returned travellers during the study period, 60% (N=30) of which were Plasmodium falciparum infections. Individuals travelling to visit friends and relatives accounted for 83% of enteric fever cases (15/18) and 41% of malaria cases (21/51). The requirement for inpatient management was over-represented among those with malaria compared to those without malaria (25% versus 2.8%; p<0.0001) and those travelling to visit friends and relatives versus those travelling for other reasons (12.1% versus 2.4%; p<0.0001). Nine new cases of HIV were diagnosed among the cohort, as well as one case of acute hepatitis B. Emerging infections among travellers included hepatitis E virus (N=6), chikungunya fever (N=4) and cutaneous leishmaniasis (N=16). Common chief complaints included gastrointestinal (N=804), dermatologic (N=440) and fever (N=287). Common specific causes of chief complaint of fever in the cohort were malaria (N=47/51 total cases), dengue fever (14/18 total cases), enteric fever (14/17 total cases) and influenza and influenza-like illness (15/21 total cases). Animal bites were the tenth most common diagnosis among tourist travellers. INTERPRETATION Our analysis of surveillance data on ill returned Canadian travellers provides a recent update to the spectrum of imported illness among travelling Canadians. Preventable travel-acquired illnesses and injuries in the cohort include malaria, enteric fever, HIV, hepatitis B, hepatitis A, influenza and animal bites. Strategies to improve uptake of preventive interventions such as malaria chemoprophylaxis, immunizations and arthropod/animal avoidance may be warranted.
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Frey D, Kayser K, Beutel T, Heidrich C, Kuhn S, Letzel S, Escobar Pinzon LC. Nackenschmerzen von Altenpflegekräften in Rheinland-Pfalz – Ergebnisse einer Querschnittserhebung. DAS GESUNDHEITSWESEN 2014. [DOI: 10.1055/s-0034-1386903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Beutel T, Frey D, Kayser K, Letzel S, Heidrich C, Kuhn S, Escobar Pinzon LC. Prävalenz psychisch belastender Arbeitsmerkmale und Zusammenhänge zu Beanspruchungsreaktionen bei Pflegekräften in der Altenpflege. DAS GESUNDHEITSWESEN 2014. [DOI: 10.1055/s-0034-1386858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Koessler J, Kobsar A, Kuhn S, Koessler A, Yilmaz P, Weinig E, Putz E, Boeck M, Klinker E. The effect of immunoadsorption with theImmusorbaTR‐350 column on coagulation compared to plasma exchange. Vox Sang 2014; 108:46-51. [DOI: 10.1111/vox.12191] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 06/13/2014] [Accepted: 07/21/2014] [Indexed: 02/06/2023]
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Wurst F, Kuhn S. Sucht und Alter. SUCHTTHERAPIE 2014. [DOI: 10.1055/s-0034-1385849] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Ruppert C, Kuhn S, Bernemann I, Klopp N, Gaede K, Koch I, Lindner M, Anton G, Schnabel PA, Schneider M, Illig T, Muley T, Günther A. DZL-Platform Biobanking. Pneumologie 2014. [DOI: 10.1055/s-0034-1376837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Jäger M, Jordan C, Theilmeier A, Wortmann N, Kuhn S, Nienhaus A, Luttmann A. Analyse der Lumbalbelastung beim manuellen Bewegen von Patienten zur Prävention biomechanischer Überlastungen von Beschäftigten im Gesundheitswesen. ZENTRALBLATT FÜR ARBEITSMEDIZIN, ARBEITSSCHUTZ UND ERGONOMIE 2014. [DOI: 10.1007/s40664-013-0010-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Olt J, Mburu P, Johnson SL, Parker A, Kuhn S, Bowl M, Marcotti W, Brown SDM. The actin-binding proteins eps8 and gelsolin have complementary roles in regulating the growth and stability of mechanosensory hair bundles of mammalian cochlear outer hair cells. PLoS One 2014; 9:e87331. [PMID: 24475274 PMCID: PMC3903700 DOI: 10.1371/journal.pone.0087331] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Accepted: 12/19/2013] [Indexed: 11/21/2022] Open
Abstract
Sound transduction depends upon mechanosensitive channels localized on the hair-like bundles that project from the apical surface of cochlear hair cells. Hair bundles show a stair-case structure composed of rows of stereocilia, and each stereocilium contains a core of tightly-packed and uniformly-polarized actin filaments. The growth and maintenance of the stereociliary actin core are dynamically regulated. Recently, it was shown that the actin-binding protein gelsolin is expressed in the stereocilia of outer hair cells (OHCs) and in its absence they become long and straggly. Gelsolin is part of a whirlin scaffolding protein complex at the stereocilia tip, which has been shown to interact with other actin regulatory molecules such as Eps8. Here we investigated the physiological effects associated with the absence of gelsolin and its possible overlapping role with Eps8. We found that, in contrast to Eps8, gelsolin does not affect mechanoelectrical transduction during immature stages of development. Moreover, OHCs from gelsolin knockout mice were able to mature into fully functional sensory receptors as judged by the normal resting membrane potential and basolateral membrane currents. Mechanoelectrical transducer current in gelsolin-Eps8 double knockout mice showed a profile similar to that observed in the single mutants for Eps8. We propose that gelsolin has a non-overlapping role with Eps8. While Eps8 is mainly involved in the initial growth of stereocilia in both inner hair cells (IHCs) and OHCs, gelsolin is required for the maintenance of mature hair bundles of low-frequency OHCs after the onset of hearing.
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MESH Headings
- Adaptor Proteins, Signal Transducing/metabolism
- Animals
- Cytoskeletal Proteins/metabolism
- Gelsolin/genetics
- Gelsolin/metabolism
- Hair Cells, Auditory, Outer/metabolism
- Hair Cells, Auditory, Outer/physiology
- Hair Cells, Auditory, Outer/ultrastructure
- Immunohistochemistry
- Mechanoreceptors/metabolism
- Mechanoreceptors/physiology
- Mechanoreceptors/ultrastructure
- Mechanotransduction, Cellular/physiology
- Mice
- Mice, Knockout
- Microfilament Proteins/metabolism
- Microscopy, Electron, Scanning
- Patch-Clamp Techniques
- Physical Stimulation
- Pyridinium Compounds
- Quaternary Ammonium Compounds
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Pridjian G, Sirois P, McRae R, Hinckley A, Rasmussen S, Kissinger P, Buekens P, Hayes E, O'Leary D, Kuhn S, Swan K, Xiong X, Wesson D. 388: A prospective study of pregnancy and newborn outcomes in mothers with West Nile virus (WNV) illness during pregnancy. Am J Obstet Gynecol 2014. [DOI: 10.1016/j.ajog.2013.10.421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Lehwald N, Duhme C, Wildner M, Kuhn S, Fürst G, Forbes SJ, Jonas S, Robson SC, Knoefel WT, Schmelzle M, Schulte Am Esch J. HGF and SDF-1-mediated mobilization of CD133+ BMSC for hepatic regeneration following extensive liver resection. Liver Int 2014; 34:89-101. [PMID: 23701640 DOI: 10.1111/liv.12195] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/01/2012] [Accepted: 04/04/2013] [Indexed: 02/13/2023]
Abstract
BACKGROUND The molecular mechanisms of haematopoietic stem cells (HSC) mobilization and homing to the liver after partial hepatectomy (PH) remain largely unexplored. METHODS Functional liver volume loss and regain was determined by computerized tomography (CT) volumetry in 30 patients following PH. Peripheral HSC mobilization was investigated by fluorescence-activated cell sorting (FACS) analyses and cytokine enzyme-linked immunosorbent assay assays. Migration of purified HSC towards hepatic growth factor (HGF) and stroma-derived factor-1 (SDF-1) gradients was tested in vitro. Mice after 70% PH were examined for HSC mobilization by FACS and cytokine mRNA expression in the liver. FACS-sorted HSC were administered after PH and hepatocyte proliferation was evaluated by immunohistochemical staining for Ki67. RESULTS Impaired liver function was noted after extended hepatic resection when compared to smaller resections. Patients with large liver resections were characterized by significantly higher levels of peripheral HSC which were positively correlated with the extent of resected liver volume and its regain after 3 weeks. Increased plasma levels of HGF, SDF-1 and insulin like growth factor (IGF-1) were evident within the first 6 hours post resection. Migration assays of human HSC in vitro showed a specific target-demonstrated migration towards recombinant HGF and SDF-1 gradients in a concentration and specific receptor (c-Met and CXCR4) dependent manner. The evaluation of peripheral human alpha foetoprotein expression demonstrated pronounced stemness following increased CD133(+) HSC in the course of liver regeneration following PH. Our human data were further validated in a murine model of PH and furthermore demonstrated increased hepatocyte proliferation subsequent to CD133(+) HSC treatment. CONCLUSION HGF and SDF-1 are required for effective HSC mobilization and homing to the liver after hepatic resection. These findings have significant implications for potential therapeutic strategies targeting chemotactant modulation and stem cell mobilization for liver protection and regeneration.
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Kuhn S, Debus J. SP-0227: Carbon ion therapy: Establishing a routine image guided workflow. Radiother Oncol 2014. [DOI: 10.1016/s0167-8140(15)30332-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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