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Spatio-temporal patterns of zooplankton in a main-stem dam affected tributary: a case study in the Xiangxi River of the Three Gorges Reservoir, China

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Science China(Life Sciences) 2019年第8期62卷 1058-1069页

作者： Xinghao Li Jie Huang sabine Filker Thorsten Stoeck Yonghong Bi Yuhe Yu Weibo Song Laboratory of Protozoology Institute of Evolution and Marine BiodiversityOcean University of ChinaQingdao266003China Key Laboratory of Aquatic Biodiversity and Conservation of Chinese Academy of Sciences and State Key Laboratory of Freshwater Ecologyand BiotechnologyInstitute of HydrobiologyChinese Academy of SciencesWuhan430072China Department of Molecular Ecology University of Technology KaiserslauternKaiserslautern67663Germany Department of Ecology University of Technology KaiserslauternKaiserslautern67663Germany Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdao266003China

As the ecologically important recipient channels for riverine ecosystems, tributaries provide unique microhabitats for microorganisms, among which zooplankton constitutes the most important heterotrophic organisms. In particular, the reduced water velocity caused by dams is more favorable for zooplankton development;therefore, dammed rivers are expected to support extremely diverse and abundant zooplankton communities and notably different spatiotemporal distribution patterns. So far,however, only very few molecular studies support these assumptions. Using high-throughput sequencing, a high number of 350 operational taxonomic units(OTUs;97% cutoff) were retrieved from 30 samples collected in the Xiangxi River, the nearest large tributary upstream of the Three Gorges Dam. Zooplankton did not show significant spatial distribution in the channel. Instead,the community structures varied significantly over sampling dates, corroborating the seasonal patterns found in lakes and ponds in the subtropical zone. As expected, the community compositions were deterministically governed by environmental filtering processes(phylogenetic clustering), in which water velocity appeared to be much less important than other investigated environmental factors. Moreover, most of the detected phylotypes(OTUs) had a relatively high(>90%) sequence similarity to previously deposited sequences, suggesting a mediocre degree of genetic novelty within the zooplankton communities in the Xiangxi River.

关键词： zooplankton high-throughput sequencing spatiotemporal distribution genetic novelty tributary main-stem dam

Differentiation of periapical granulomas and cysts by using dental MRI: a pilot study

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International Journal of Oral Science 2018年第3期10卷 152-159页

作者： Alexander Juerchott Thorsten Pfefferle Christa Flechtenmacher Johannes Mente Martin Bendszus sabine Heiland Tim Hilgenfeld Department of Neuroradiology Heidelberg University Hospital Division of Endodontics and Dental Traumatology Department of Conservative Dentistry Heidelberg University Hospital Institute of Pathology Heidelberg University Hospital Division of Experimental Radiology Department of Neuroradiology Heidelberg University Hospital

The purpose of this pilot study was to evaluate whether periapical granulomas can be differentiated from periapical cysts in vivo by using dental magnetic resonance imaging(MRI). Prior to apicoectomy, 11 patients with radiographically confirmed periapical lesions underwent dental MRI, including fat-saturated T2-weighted(T2 wFS) images, non-contrast-enhanced T1-weighted images with and without fat saturation(T1 w/T1 wFS), and contrast-enhanced fat-saturated T1-weighted(T1 wFS+C) images. Two independent observers performed structured image analysis of MRI datasets twice. A total of 15 diagnostic MRI criteria were evaluated, and histopathological results(6 granulomas and 5 cysts) were compared with MRI characteristics. Statistical analysis was performed using intraclass correlation coefficient(ICC), Cohen’s kappa(κ), Mann–Whitney U-test and Fisher’s exact test. Lesion identification and consecutive structured image analysis was possible on T2 wFS and T1 wFS+C MRI images. A high reproducibility was shown for MRI measurements of the maximum lesion diameter(intraobserver ICC = 0.996/0.998; interobserver ICC = 0.997), for the "peripheral rim" thickness(intraobserver ICC = 0.988/0.984; interobserver ICC = 0.970), and for all non-quantitative MRI criteria(intraobserver-κ = 0.990/0.995; interobserver-κ = 0.988). In accordance with histopathological results, six MRI criteria allowed for a clear differentiation between cysts and granulomas:(1) outer margin of lesion,(2) texture of "peripheral rim" in T1 wFS+C,(3)texture of "lesion center" in T2 wFS,(4) surrounding tissue involvement in T2 wFS,(5) surrounding tissue involvement in T1 wFS+C and(6) maximum "peripheral rim" thickness(all: P < 0.05). In conclusion, this pilot study indicates that radiation-free dental MRI enables a reliable differentiation between periapical cysts and granulomas in vivo. Thus, MRI may substantially improve treatment strategies and help to avoid unnecessary surgery in apical periodontitis.

关键词： Differentiation of periapical granulomas and cysts by using dental MRI a pilot study

Enhanced migration of tissue inhibitor of metalloproteinase overexpressing hepatoma cells is attributed to gelatinases: Relevance to intracellular signaling pathways

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World Journal of Gastroenterology 2005年第8期11卷 1096-1104页

作者： Elke Roeb Anja-Katrin Bosserhoff sabine Hamacher Bettina Jansen Judith Dahmen Sandra Wagner Siegfried Matern Department of Internal Medicine Ⅲ Institute of Pathology

AIM: To study the effect of gelatinases (especially MMP-9) on migration of tissue inhibitor of metalloproteinase (TIMP-1) overexpressing hepatoma cells. METHODS: Wild type HepG2 cells, cells stably transfected with TIMP-1 and TIMP-1 antagonist (MMP-9-H401A, a catalytically inactive matrix metalloproteinase (MMP) which still binds and neutralizes TIMP-1) were incubated in Boyden chambers either with or without Galardin (a synthetic inhibitor of MMP-1, -2, -3, -8, -9) or a specific inhibitor of gelatinases. RESULTS: Compared to wild type HepG2 cells, the cells overexpressing TIMP-1 showed 115% migration (P<0.05) and the cells overexpressing MMP-9-H401A showed 62% migration (P<0.01). Galardin reduced cell migration dose dependently in all cases. The gelatinase inhibitor reduced migration in TIMP-1 overexpressing cells predominantly. Furthermore, we examined intracellular signal transduction pathways of TIMP-1-dependent HepG2 cells. TIMP-1 deactivates cell signaling pathways of MMP-2 and MMP-9 involving p38 mitogen-activated protein kinase. Specific blockade of the ERK pathway suppresses gelatinase expression either in the presence or absence of TIMP-1. CONCLUSION: Overexpressing functional TIMP-1-enhanced migration of HepG2-TIMP-l cells depends on enhanced MMP-activity, especially MMP-9.

关键词： HepG2 MMP-2 MMP-9 p38MAPK Galardin Genistein

Spontaneous elimination of hepatitis C virus infection: A retrospective study on demographic, clinical, and serological correlates

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World Journal of Gastroenterology 2007年第31期13卷 4224-4229页

作者： Perdita Wietzke-Braun Larissa Bettina Mnhardt Albert Rosenberger Angela Uy Giuliano Ramadori sabine Mihm Department of Gastroenterology and Endocrinology Robert-Koch-Str.40 37075 Gttingen Germany Department of Genetic Epidemiology Humboldtallee 32 Gttingen 37073 Germany Department of Microbiology Kreuzbergring 57 Gttingen Georg-August-Universitt Gttingen 37075 Germany

To find correlates to spontaneous clearance of hepatitis C virus （HCV） infection, this study compared individuals with self-limited and chronic infection with regard to clinical, demographic, and serological pa- rameters. METHODS： Sixty-seven anti-HCV positive and repeatedly HCV RNA negative individuals were considered to have resolved HCV infection spontaneously. To determine the viral genotype these patients had been infected with HCV serotyping was performed. For comparison reasons, 62 consecutive patients with chronic hepatitis C were enrolled. Cases and controls were compared stratified for age and sex. RESULTS： Retrospective analysis showed （1） a lower humoral reactivity to HCV in patients with self-limited compared to chronic HCV-infection and （2） that younger age, history of iv drug use, and acute/post-acute hepatitis A or B co-infections, but not viral genotypes, are independent correlates for spontaneous HCV clearance. CONCLUSION： The stronger humoral reactivity to HCV in patients with persistent infections and in those with a history of iv drug use is supposed to be due to continuous or repeated contact（s） to the antigen. Metachronous hepatitis A or hepatitis B infections might favor HCV clearance.

关键词： Hepatitis C virus Hepatitis Self-limitedinfection Anti-HCV antibodies Co-infection HCVserotype

C-reactive protein is a prognostic indicator in patients with perihilar cholangiocarcinoma

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World Journal of Gastroenterology 2006年第34期12卷 5495-5500页

作者： Thomas Gerhardt sabine Milz Michael Schepke Georg Feldmann Martin Wolff Tilman Sauerbruch Franz Ludwig Dumoulin Department of Internal Medicine I University Hospital Bonn Germany Department of Surgery University Hospital Bonn Germany

AIM： To evaluate prognostic indicators for the outcome of patients with perihilar extrahepatic cholangiocarcinoma in an unselected cohort. METHODS： We retrospectively analyzed 98 patients with perihilar cholangiocarcinoma. Twenty-three patients （23.5%） underwent tumor resection. Patients with non-resectable tumors underwent either transpapillary or percutaneous transhepatic biliary drainage. Additionally, 32 patients （32.7%） received photodynamic therapy （PDT） and 18 patients （18.4%） systemic chemotherapy. Predefined variables at the time of diagnosis and characteristics considering the mode of treatment were entered into a Cox＇s proportional hazards model. Included in the analysis were age, tumor stage following the modified Bismuth-Corlette classification, bilirubin, prothrombin time （PT）, C-reactive protein （CRP）, carbohydrate antigen 19-9 （CA19-9）, history of weight loss, surgical resection, chemotherapy and PDT. RESULTS： The Kaplan-Meier estimate of overall median survival was 10.5 （95%CI： 8.4-12.6） mo. In the univariate analysis, low Bismuth stage, low CRP and surgical resection correlated significantly with better survival. In the multivariate analysis, only CRP （P = 0.005） and surgical resection （P = 0.029） were found to be independently predictive of survival in the cohort. Receiver operating characteristic （ROC） analysis identified a CRP level of 11.75 mg/L as the value associated with the highest sensitivity and specificity predicting a survival 〉 5 too. Applying Kaplan-Meier analysis, patients with a CRP 〈 12 mg/L at the time of diagnosis had a significantly longer median survival than patients with higher values （16.2 vs 7.6 mo; P = 0.009）.CONCLUSION： This retrospective analysis identified CRP level at the time of diagnosis as a novel indicator for the prognosis of patients with perihilar cholangiocarcinoma. It should be evaluated in future prospective trials on this entity.

关键词： Perihilar cholangiocarcinoma Prognosticfactors C-reactive protein Resection Outcome

The NMR core analyzing tomograph:a multi-functional tool for non-destructive testing of building materials

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Magnetic Resonance Letters 2023年第3期3卷 207-219,I0003页

作者： sabine Kruschwitz Sarah Munsch Melissa Telong Wolfram Schmidt Thilo Bintz Matthias Fladt Ludwig Stelzner Bundesanstalt für Materialforschung und-prüfung Unter den Eichen 87Berlin12205Germany Technische Universitat Berlin Gustav-Meyer-Allee 25Berlin13355Germany

NMR is becoming increasingly popular for the investigation of building materials as it is a non-invasive technology that does not require any sample preparation nor causes damage to the *** on the specific application it can offer insights into properties like porosity and spatial saturation degree as well as pore *** it enables the determination of moisture transport properties and the(re-)distribution of internal moisture into different reservoirs or chemical phases upon damage and ***,as yet most investigations were carried out using devices originally either designed for geophysical applications or the analysis of rather homogeneous small scale(<10 mL)*** paper describes the capabilities of an NMR tomograph,which has been specifically optimized for the investigation of larger,heterogeneous building material samples(diameters of up to 72 mm,length of up to 700 mm)with a high flexibility due to interchangeable coils allowing for a high SNR and short echo times(50-80 ms).

关键词： Natural stone Concrete Sensitivity Moisture transport Cement hydration Supplementary cementitious materials Frost and salt attack Fire spalling

The 3’-untranslated region contributes to the pregnane X receptor(PXR) expression downregulation by PXR ligands and up-regulation by glucocorticoids

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Acta Pharmaceutica Sinica B 2020年第1期10卷 136-152页

作者： Tomas Smutny Jan Dusek Lucie Hyrsova Jana Nekvindova Alzbeta Horvatova Stanislav Micuda sabine Gerbal-Chaloin Petr Pavek Department of Pharmacology and Toxicology Faculty of Pharmacy in Hradec KraloveCharles UniversityHradec Kralove CZ-50005Czech Republic Institute of Clinical Biochemistry and Diagnostics University Hospital Hradec KraloveHradec Kralove CZ-50005Czech Republic Department of Pharmacology Faculty of Medicine in Hradec KraloveCharles UniversityHradec Kralove CZ-50003Czech Republic IRMB INSERMUniversity MontpellierMontpellierFrance

Pregnane X receptor(PXR)is the major regulator of xenobiotic *** itself is controlled by various signaling molecules including ***,negative feed-back regulation has been proposed at the transcriptional *** examined the involvement of the 3’-untranslated region(3’-UTR)of NR1I2 mRNA and microRNAs in PXR-and glucocorticoid receptor(GR)-mediated regulation of NR1I2 gene *** ligands were found to significantly downregulate NR1I2 mRNA expression in a set of 14 human hepatocyte ***,PXR was downregulated by PCN in the C57/BL6 mice *** mechanistic studies with the full-length 3’-UTR cloned into luciferase reporter or expression vectors,we showed that the 3’-UTR reduces PXR *** the miRNAs tested,miR-18a-5p inhibited both NR 112 expression and CYP3A4 gene ***,we observed significant upregulation of miR-18a-5p expression 6 h after treatment with the PXR ligand rifampicin,which indicates a putative mechanism underlying NR1I2 negative feed-back regulation in hepatic ***,glucocorticoids upregulated NR1I2 expression not only through the promoter region but also via 3’-UTR regulation,which likely involves downregulation of *** conclude that miR-18a-5p is involved in the down-regulation of NR1I2expression by its ligands and in the upregulation of NR1I2 mRNA expression by glucocorticoids in hepatic cells.

关键词： Gene expression MicroRNA Glucocorticoid Regulation Pregnane X receptor Cytochrome P4503A4

An unhappy triad:Hemochromatosis, porphyria cutanea tarda and hepatocellular carcinoma-A case report

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World Journal of Gastroenterology 2007年第13期13卷 1998-2001页

作者： Martina T Mogl Andreas Pascher sabine J Presser Michael Schwabe Peter Neuhaus Natascha C Nuessler Department of Surgery Charité Campus Virchow-Klinikum Augustenburger Platz 1 Berlin 13353 Germany

Liver fibrosis and cirrhosis are predisposing factors for the development of hepatocellular carcinoma （HCC）. Hemosiderosis has also been described to trigger carcinogenesis. A significant iron overload, as found in hereditary hemochromatosis （HHC）, is a risk factor for HCC and may also promote the symptoms of porphyria cutanea tarda （PCT）. A 68-year old male patient presented to our clinic with a suspected HCC, elevated alpha-fetoprotein but normal liver function tests. He reported a 25 year-old history of vitiligo upon exposure to sunlight. The patient underwent an extended left hemihepatectomy, and the recovery was uneventful, with the exception of a persistent hyperbilirubinemia. Perfusion problems and extrahepatic cholestasis were ruled out by CT-scan with angiography and MR-cholangiopancreatography. However, MR1 showed an iron overload. Histology confirmed the HCC （pT3, pN0, G3, R0） and revealed a portal fibrosis and hemosiderosis. Based on the skin lesions we suspected a PCT that was confirmed by laboratory tests showing elevated porphyrin, uroporphyrin, coproporphyrin and porphobilinogen. Concurrently, molecular diagnostics revealed homozygosity for the C282Y mutation within the hemochromatosis HFE gene. After phlebotomy and normalization of liver function tests the patient was discharged. This is the first case ever showing the unusual combination of HCC in a fibrotic liver with HHC and PCT. This diagnosis not only warrants oncological follow-up but also symptomatic therapy to normalize iron metabolism and thereby improve liver function and alleviate the symptoms of HHC and PCT. Thus progression of fibrosis may be prevented and liver regeneration supported.

关键词： Hepatocellular carcinoma Hemochromatosis Porphyria cutanea tarda

Impact of hypothermia on the biomechanical effect of epithelium-off corneal cross-linking

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Eye and Vision 2021年第3期8卷 31-35页

作者： Hormoz Abdshahzadeh Reyhaneh Abrishamchi Emilio A.Torres-Netto sabine Kling Nikki L.Hafezi Mark Hillen Farhad Hafezi Ocular Cell Biology Group Center for Applied Biotechnology and Molecular MedicineUniversity of ZurichWinterthurerstrasse 1908057 ZurichSwitzerland ELZA Institute Dietikon/ZurichSwitzerland Department of Ophthalmology Paulista School of MedicineFederal University of Sao PauloSao PauloBrazil Faculty of Medicine University of GenevaGenevaSwitzerland OPTIC-team Computer Vision LaboratoryETH ZurichZurichSwitzerland Department of Ophthalmology University of WenzhouWenzhouChina USC Roski Eye Institute USC Los AngelesLos AngelesCAUSA

Background:The corneal cross-linking(CXL)photochemical reaction is essentially dependent on oxygen and hypothermia,which usually leads to higher dissolved oxygen levels in tissues,with potentially greater oxygen availability for ***,we evaluate whether a reduction of corneal temperature during CXL may increase oxygen availability and therefore enhance the CXL biomechanical stiffening effect in ex vivo porcine ***:One hundred and twelve porcine corneas had their epithelium manually debrided before being soaked with 0.1%hypo-osmolaric *** corneas were equally assigned to one of four *** 2 and 4 underwent accelerated epithelium-off CXL using 9 mW/cm^(2) irradiance for 10 min,performed either in a cold room temperature(group 2,4℃)or at standard room temperature(group 4,24℃).Groups 1 and 3 served as non-crosslinked,temperature-matched *** a stress-strain extensometer,the elastic moduli of 5-mm wide corneal strips were analyzed as an indicator of corneal ***:Accelerated epithelium-off CXL led to significant increases in the elastic modulus between 1 and 5%of strain when compared to non-cross-linked controls(P<0.05),both at 4℃(1.40±0.22 vs 1.23±0.18 N/mm)and 24℃(1.42±0.15 vs 1.19±0.11 N/mm).However,no significant difference was found between control groups(P=0.846)or between groups in which CXL was performed at low or standard room temperature(P=0.969).Conclusions:Although initial oxygen availability should be increased under hypothermic conditions,it does not appear to play a significant role in the biomechanical strengthening effect of epithelium-off CXL accelerated protocols in ex vivo porcine corneas.

关键词： Corneal cross-linking CXL Keratoconus Temperature Oxygen diffusion Hypothermia