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Biological performance of particleboard incorporated with boron minerals

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Journal of Forestry Research 2017年第1期28卷 195-203页

作者： Evren Terzi S.Nami Kartal Philippe Gerardin claudia Marcela Ibanez Tsuyoshi Yoshimura Department of Forest Biology and Wood Protection Technology Faculty of ForestryIstanbul University34473 BahcekoyIstanbulTurkey Faculte des Sciences et Technologies Universite de Lorraine54506 Vandoeuvre-les-Nancy CedexFrance Unidad Academica de Gestion Tecnologica Departamento TecnologicoFacultad de QuimicaUniversidad de la Republica UruguayMontevideoUruguay Laboratory of Innovative Humano-Habitability Research Institute for Sustainable Humanosphere(RISH)Kyoto UniversityUjiKyoto 611-0011Japan

We compared resistance to decay, mold fungi, termites and insect larvae of particleboards incorporated with the raw boron minerals ulexite and colemanite to that of particleboards impregnated with the commercial boron preservative zinc borate, or boric acid plus a borax mixture. We also quantified water absorption, thickness swell and boron release of particleboards. Ulexite had the best decay resistance, and colemanite had the best termite resistance. However, ulexite and colemanite were not as effective as zinc borate or the boric acid/borax mixture in preventing mold growth. In general, the boric acid/borax mixture combination was more effective against Anobium larvae than the other treatments. Less boron was released by specimens containing zinc borate and colemanite than by those containing ulexite or the boric acid/borax mixture. In general, water absorption and thickness swell were similar among the different treatments, but both were slightly higher in the ulexite-incorporated specimens. Further mechanical tests will be needed to evaluate the particle- board properties and thereby the compatibility of these boron minerals with various manufacturing processes.

关键词： Biological resistance Borax Boric acid Colemanite Particleboard Ulexite

Control of PHERES1 Imprinting in Arabidopsis by Direct Tandem Repeats

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Molecular Plant 2009年第4期2卷 654-660页

作者： Corina Belle R. Villar Aleksandra Erilova Grigory Makarevich Raphael Trosch claudia Kohler Department of Biology and Zurich-Basel Plant Science Center Swiss Federal Institute of Technology ETH Centre CH-8092 Zurich Switzerland

Genomic imprinting is an epigenetic phenomenon that causes monoallelic expression of specific genes dependent on the parent-of-origin. Imprinting of the Arabidopsis gene PHERES1 requires the function of the FERTILIZATION INDEPENDENT SEED （FIS） Polycomb group complex as well as a distally located methylated region containing a tandem triple repeat sequence. In this study, we investigated the regulation of the close PHERES1 homolog PHERES2. We found that PHERES2 is also a direct target gene of the FIS Polycomb group complex, but, in contrast to PHERES1, PHERES2 is equally expressed from maternal and paternal alleles. Thus, PHERES2 is not regulated by genomic imprinting, correlating with the lack of tandem repeats at PHERES2. Eliminating tandem repeats from the PHERES1 locus abolishes PHERES1 imprinting, demonstrating that tandem repeats are essential forPHERES1 imprinting. Taking these results together, our study shows that the recently duplicated genes PHERES1 and PHERES2 are both target genes of the FIS Polycomb group complex but only PHERES1 is regulated by genomic imprinting, which is likely caused by the presence of repeat sequences in the proximity of the PHERES1 locus.

关键词： Chromatin structure and remodeling epigenetics gene regulation gene silencing gametogenesis and fertilization.

Divide and conquer: two stem cell populations in squamous epithelia, reserves and the active duty forces

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International Journal of Oral Science 2019年第4期11卷 252-264页

作者： Spencer Dunaway Alexandra Rothaus Yuhang Zhang Ana Luisa Kadekaro Thomas Andl claudia DAndl Department of Dermatology College of MedicineUniversity of CincinnatiCincinnatiOHUSA Burnett School of Biomedical Sciences University of Central FloridaOrlandoFLUSA Division of Pharmaceutical Sciences College of PharmacyUniversity of CincinnatiCincinnatiOHUSA

Stem cells are of great interest to the scientific community due to their potential role in regenerative and rejuvenative ***,their role in the aging process and carcinogenesis remains *** DNA replication in stem cells may contribute to the background mutation rate and thereby to cancer,reducing proliferation and establishing a relatively quiescent stem cell compartment has been hypothesized to limit DNA replication-associated *** the other hand,as the main function of stem cells is to provide daughter cells to build and maintain tissues,the idea of a quiescent stem cell compartment appears *** observations in mice have led to the idea of separated stem cell compartments that consist of cells with different proliferative *** epithelia of short-lived rodents appear to lack quiescent stem *** stem cells of different species and different organs(comparative stem cell biology)may allow us to elucidate the evolutionary pressures such as the balance between cancer and longevity that govern stem cell biology(evolutionary stem cell biology).The oral mucosa and its stem cells are an exciting model system to explore the characteristics of quiescent stem cells that have eluded biologists for decades.

关键词： organs elude stem

Amniotic fluid stem cell-based models to study the effects of gene mutations and toxicants on male germ cell formation

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Asian Journal of Andrology 2012年第2期14卷 247-250页

作者： claudia Gundacker Helmut Dolznig Mario Mikula Margit Rosner Oliver Brandau Markus Hengstschlager Medical Genetics Medical University of Vienna Vienna 1090 Austria

Male infertility is a major public health issue predominantly caused by defects in germ cell development. In the past, studies on the genetic regulation of spermatogenesis as well as on negative environmental impacts have been hampered by the fact that human germ cell development is intractable to direct analysis in vivo. Compared with model organisms including mice, there are fundamental differences in the molecular processes of human germ cell development. Therefore, an in vitro model mimicking human sperm formation would be an extremely valuable research tool. In the recent past, both human embryonic stem （ES） cells and induced pluripotent stem （iPS） cells have been reported to harbour the potential to differentiate into primordial germ cells and gametes. We here discuss the possibility to use human amniotic fluid stem （AFS） ceils as a biological model. Since their discovery in 2003, AFS cells have been characterized to differentiate into cells of all three germ layers, to be genomically stable, to have a high proliferative potential and to be non-tumourigenic. In addition, AFS cells are not subject of ethical concerns. In contrast to iPS cells, AFSs cells do not need ectopic induction of pluripotency, which is often associated with only imperfectly cleared epigenetic memory of the source cells. Since AFS cells can be derived from amniocentesis with disease-causing mutations and can be transfected with high efficiency, they could be used in probing gene functions for spermatogenesis and in screening for male reproductive toxicity.

关键词： amniotic fluid human genetics infertility primordial germ cells reproduction spermatogenesis stem cells toxicity

Vessel density in OCT angiography permits differentiation between normal and glaucomatous optic nerve heads

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International Journal of Ophthalmology(English edition) 2018年第5期11卷 835-843页

作者： claudia Lommatzsch Kai Rothaus Joerg Michael Koch Carsten Heinz Swaantje Grisanti Department of Ophthalmology St.Franziskus Hospital Department of Ophthalmology University of Essen Department of Ophthalmology University of Luebeck

AIM：To evaluate whether optical coherence tomography angiography（OCTA） can detect altered vessel density（VD） at the optic nerve head（ONH） in glaucoma *** attention is paid to the accuracy of the OCTA technique for distinguishing healthy from glaucomatous ***：A total of 171 eyes were examined by the OCTA system Angio Vue^TM（Optovue）：97 eyes diagnosed with glaucoma and 74 healthy control *** papillary and peripapillary VD was ***,the VD was correlated with different structural and functional *** order to test the accuracy of differentiation between eyes with and without glaucoma,we calculated the receiver operating characteristic curve（ROC） and the area under the curve（AUC）.RESULTS：The papillary and peripapillary VD in glaucomatous eyes was significantly lower than in healthy eyes（P〈0.05）.The VD of the nasal peripapillary sector was significantly lower than in the other *** further the disease had progressed [measured by determining the thickness of the ganglion cell complex（GCC） and the retinal nerve fiber layer（RNFL）] the greater the VD *** AUC discriminated well between glaucomatous and normal eyes（consensus classifier 94.2%）.CONCLUSION：OCTA allows non-invasive quantification of the peripapillary and papillary VD,which is significantly reduced in glaucomatous eyes and accurately distinguishes between healthy and diseased *** expands the spectrum of procedures for detecting and monitoring glaucoma.

关键词： optical coherence tomography angiography glaucoma optic nerve head blood flow

Hepatocytic differentiation of mesenchymal stem cells in cocultures with fetal liver cells

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World Journal of Gastroenterology 2006年第15期12卷 2394-2397页

作者： claudia Lange Helge Bruns Dietrich Kluth Axel R Zander Henning C Fiegel Center of Bone Marrow Transplantation University Hospital Hamburg-Eppendorf Martinistrasse 52D-20246 HamburgGermany Department of Pediatric Surgery University Hospital Hamburg-Eppendorf Martinistrasse 52D-20246 HamburgGermany Department of Pediatric Surgery University Hospital Hamburg-Eppendorf Martinistrasse 52D-20246 Hamburg Germany

AIM： To investigate the hepatocytic differentiation of mesenchymal stem cells （MSCs） in co-cultures with fetal liver cells （FLC） and the possibility to expand differentiated hepatocytic cells. METHODS： MSCs were marked with green fluorescent protein （GFP） by retroviral gene transduction. Clonal marked MSCs were either cultured under liver stimulating conditions using fibronectin-coated culture dishes and medium supplemented with stem cell factor （SCF）, hepatocyte growth factor （HGF）, epidermal growth factor （EGF）, and fibroblast growth factor 4 （FGF-4） alone, or in presence of freshly isolated FLC. Cells in co-cultures were harvested, and GFP＋ or GFP- cells were separated using fluorescence activated cell sorting. Reverse transcription-polymerase chain reaction （RT-PCR） for the liver specific markers cytokeratin-18 （CK-18）, albumin, and alpha-fetoprotein （AFP） was performed in different cell populations. RESULTS- Under the specified culture conditions, rat MSCs co-cultured with FLC expressed albumin, CK-18, and AFP-RNA over two weeks. At wk 3, MSCs lost hepatocytic gene expression, probably due to overgrowth of the cocultured FLC. FLC also showed a stable liver specific gene expression in the co-cultures and a very high growth potential. CONCLUSION： The rat MSCs from bone marrow can differentiate hepatocytic cells in the presence of FLC in vitro and the presence of MSCs in co-cultures also prorides a beneficial environment for expansion and differentiation of FLC.

关键词： Hepatic stem cells Mesenchymal stem cells Fetal liver cells Co-culture

Scalability of biomass-derived graphene derivative materials as viable anode electrode for a commercialized microbial fuel cell: A systematic review

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Chinese Journal of Chemical Engineering 2023年第3期55卷 277-292页

作者： Mustapha Omenesa Idris claudia Guerrero-Barajas Hyun-Chul Kim Asim Ali Yaqoob Mohamad Nasir Mohamad Ibrahim School of Chemical Sciences Universiti Sains Malaysia11800 PenangMalaysia Department of Pure and Industrial Chemistry Kogi State UniversityP.M.B 1008 AnyigbaKogi StateNigeria Laboratorio de Biotecnologia Ambiental Departamento de BioprocesosUnidad Profesional Interdisciplinaria de BiotecnologiaInstituto Politecnico NacionalAv.Acueducto s/nCol.Barrio La Laguna Ticoman07340 Mexico CityMexico Research Institute for Advanced Industrial Technology College of Science and TechnologyKorea UniversitySejong 30019Republic of Korea

Microbial fuel cell(MFC) is an advanced bioelectrochemical technique that can utilize biomass materials in the process of simultaneously generating electricity and biodegrading or bio transforming toxic pollutants from wastewater. The overall performance of the system is largely dependent on the efficiency of the anode electrode to enhance electron transportation. Furthermore, the anode electrode has a significant impact on the overall cost of MFC setup. Hence, the need to explore research focused towards developing cost-effective material as anode in MFC. This material must also have favourable properties for electron transportation. Graphene oxide(GO) derivatives and its modification with nanomaterials have been identified as a viable anode material. Herein, we discussed an economically effective strategy for the synthesis of graphene derivatives from waste biomass materials and its subsequent fabrication into anode electrode for MFC applications. This review article offers a promising approach towards replacing commercial graphene materials with biomass-derived graphene derivatives in a view to achieve a sustainable and commercialized MFC.

关键词： Microbial fuel cell Biomass Anode fabrication Catalyst Design Cost-effective performance

Shade shelters increase survival and photosynthetic performance of oak transplants at abandoned fields in semi-arid climates

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Journal of Forestry Research 2013年第1期24卷 23-28页

作者： claudia González-Salvatierra Ernesto Iván Badano Joel Flores Juan Pablo Rodas División de Ciencias Ambientales Instituto Potosino de Investigación Científica y TecnológicaA.C.Camino a la Presa San José 2055C.P. 78216San Luis PotosíS.L.P.México.

Forest restorations conducted in semiarid, seasonally dry climates must deal with the intense drought stress that affects tree seedlings during the dry season. Although this water deficit is the most commonly invoked source of mortality for seedlings, several other environmental factors may also preclude survival of transplants. For instance, it has been widely reported that excessive light reduces the efficiency of the photosynthetic apparatus, hence decreasing plant survival, but most seedling transplants in deforested areas are conducted under these light conditions. This study is focused in determining whether excessive light affects the photosynthetic performance and survival of Quercus coccolobifolia, a Mexican oak species, when their seedlings are transplanted in semiarid deforested areas. Further, this study tests the possibility of using artificial shade shelters to improve the ecophysiological performance and survival of seedlings. Oak seedlings were transplanted under full sunlight conditions and beneath artificial shade shelters of two different colors： white and black. To reduce water stress, and hence isolate the effects of light treatments, a drip irrigation system was implemented at each experimental plot. Seedling survival was monitored weekly for 128 days and photosynthetic performance was assessed by measuring chlorophyll fluorescence at three opportunities during the experiment. Sun-exposed seedlings showed lower photosynthetic performance and survival rates than those beneath shelters of both colors. These results suggest that sunlight damage can reduce seedling survival when they are transplanted in exposed sites, and that shade shelters can improve the success of forest restoration programs in semiarid climates.

关键词： chlorophyll fluorescence light stress photoinhibition reforestation forest restoration

Smoking increases the risk of extraintestinal manifestations in Crohn's disease

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World Journal of Gastroenterology 2014年第34期20卷 12269-12276页

作者： claudia Ott Angela Takses Florian Obermeier Elisabeth Schnoy Martina Müller Department of Internal Medicine I University of Regensburg93042 RegensburgGermany

AIM:To demonstrate a high prevalence of extraintestinal manifestations(EIMs)in a prospective populationbased cohort of inflammatory bowel disease(IBD)patients at first diagnosis as well as during the early course of the ***:EIMs are common in patients with *** on the frequency of EIMs have mostly been assessed in patients from tertiary centers;however,data about the prevalence of EIMs at first diagnosis as well as factors influencing their incidence during the early course of disease from prospective population-based cohorts are *** present data of patients of our population-based"Oberpfalz cohort"(Bavaria,Germany)from first diagnosis(up to 3 mo after first diagnosis)as well as during the early course of the *** risk factors were assessed by calculating the relative risk(RR)as well as using logistic regression ***:In total,data of 257 newly diagnosed patients with IBD were evaluated[161 Crohn’s disease(CD),96 ulcerative colitis(UC)].Median duration of follow-up was 50 mo after first *** 63.4%of all patients(n=163),an EIM was diagnosed at any point during the observation *** first diagnosis,patients with CD had a significantly increased risk of an EIM[n=69(42.9%)]compared with UC patients[n=21(21.9%);P<0.001;RR=1.96;95%CI:1.30-2.98].Active smoking increased the risk of CD patients developing an EIM during the early course of the disease,but notably not of UC patients(P=0.046;RR=1.96;95%CI:1.01-3.79).In addition,using logistic regression analysis,the need for IBD-related surgery and a young age at first diagnosis were identified as risk factors for the development of an EIM in CD *** association with EIMs was found for the factors sex,localization of the disease and positive family history of *** contrast,no key factors which increased the risk of development of an EIM could be identified in UC ***:We found a high prevalence of EIM in this cohort at first diagnosis and during th

关键词： Extraintestinal manifestations Crohn's disease Ulcerative colitis Smoking Surgery Age at onset