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81.
Jens?Frederik?AggerEmail author Suman?Paul Anna-Bodil?Christoffersen J?rgen?Steen?Agerholm 《Acta veterinaria Scandinavica》2013,55(1):80
The aim was to identify risk factors associated with Coxiella burnetii antibody positivity in bulk tank milk (BTM) samples from 100 randomly selected Danish dairy cattle herds. Antibody levels were measured by an enzyme-linked immuno-sorbent assay. Before testing the herds, the farm managers were interviewed about hired labour, biosecurity, housing and herd health during the 12 months prior to the study. Variables considered important for C. burnetii antibody positivity in multivariable logistic regression analysis included the sharing of machines between farms (OR?=?3.6), human contacts (OR?=?4.2), artificial insemination by other people than artificial insemination technicians (OR?=?7.7), routine herd health contract with the veterinarian (OR?=?4.3) and hygiene precautions taken by veterinarians (OR?=?5). In addition, herd size, hired labour, trading of cattle between farms, quarantine and use of calving and disease pens also showed significant association in univariable analysis. This study demonstrates that strict biosecurity is important for the prevention of infections with C. burnetii. 相似文献
82.
Jens Ewers Doris Freier-Schröder Hans-Joachim Knackmuss 《Archives of microbiology》1990,154(4):410-413
Two isoprene (2-methyl-1,3-butadiene) utilizing bacteria, Alcaligenes denitrificans ssp. xylosoxidans JE 75 and Rhodococcus erythropolis JE 77, were identified as highly efficient cooxidizers of TCE, cis- and transdichloroethene, 1,1-dichloroethene and vinylchloride. Isoprene grown cells eliminate chloride from TCE in stoichiometric amounts and tolerate high concentrations of TCE. 相似文献
83.
Madsen BE Ramos EM Boulard M Duda K Overgaard J Nordsmark M Wiuf C Hansen LL 《PloS one》2008,3(6):e2492
THE BACKGROUND: Ribonuclease L (RNASEL), encoding the 2'-5'-oligoadenylate (2-5A)-dependent RNase L, is a key enzyme in the interferon induced antiviral and anti-proliferate pathway. Mutations in RNASEL segregate with the disease in prostate cancer families and specific genotypes are associated with an increased risk of prostate cancer. Infection by human papillomavirus (HPV) is the major risk factor for uterine cervix cancer and for a subset of head and neck squamous cell carcinomas (HNSCC). HPV, Epstein Barr virus (EBV) and sequences from mouse mammary tumor virus (MMTV) have been detected in breast tumors, and the presence of integrated SV40 T/t antigen in breast carcinomas correlates with an aggressive phenotype and poor prognosis. A genetic predisposition could explain why some viral infections persist and induce cancer, while others disappear spontaneously. This points at RNASEL as a strong susceptibility gene. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate the implication of an abnormal activity of RNase L in the onset and development of viral induced cancers, the study was initiated by searching for germline mutations in patients diagnosed with uterine cervix cancer. The rationale behind is that close to 100% of the cervix cancer patients have a persistent HPV infection, and if a defective RNase L were responsible for the lack of ability to clear the HPV infection, we would expect to find a wide spectrum of mutations in these patients, leading to a decreased RNase L activity. The HPV genotype was established in tumor DNA from 42 patients diagnosed with carcinoma of the uterine cervix and somatic tissue from these patients was analyzed for mutations by direct sequencing of all coding and regulatory regions of RNASEL. Fifteen mutations, including still uncharacterized, were identified. The genotype frequencies of selected single nucleotide polymorphisms (SNPs) established in the cervix cancer patients were compared between 382 patients with head and neck squamous cell carcinomas (HNSCC), 199 patients with primary unilateral breast cancer and 502 healthy Danish control individuals. We found that the genotype frequencies of only one of the 15 mutations, the yet uncharacterized 5'UTR mutation rs3738579 differed significantly between cancer patients and control individuals (P-value: 4.43x10(-5)). CONCLUSION/SIGNIFICANCE: In conclusion, we have discovered an increased risk, a heterozygous advantage and thereby a protective effect linked to the RNASEL SNP rs3738579. This effect is found for patients diagnosed with carcinoma of the uterine cervix, HNSCC, and breast cancer thus pointing at RNASEL as a general marker for cancer risk and not restricted to familial prostate cancer. 相似文献
84.
On the morphology of antennular sensory and attachment organs in cypris larvae of the deep‐sea vent/seep barnacles,Ashinkailepas and Neoverruca 下载免费PDF全文
Takefumi Yorisue Benny K. K. Chan Ryusuke Kado Hiromi Watanabe Koji Inoue Shigeaki Kojima Jens T. Høeg 《Journal of morphology》2016,277(5):594-602
Barnacle cypris larvae show high morphological variation in the organs used in search of and attaching to a substratum. This variation may represent adaptation to the habitat of the species. Here, we studied SEM level morphologies of cypris antennular sensory and attachment organs in a deep‐sea vent endemic species (Neoverruca sp.) and a vent/seep inhabiting species (Ashinkailepas seepiophila). We compare them with three species from other environments. The antennular morphologies of Neoverruca sp. and A. seepiophila were similar, which is consistent with recent molecular studies showing a close relationship of the two species. The setation pattern of the antennules was very conservative among species from various environments. In contrast, striking differences were observed in the structure of the attachment organ (the third antennular segment). Neoverruca sp. and A. seepiophila had no velum or a skirt surrounding the attachment disc on the third segment, while other cirripede cyprids almost always have either of these structures. In addition, both cyprids of A. seepiophila and Neoverruca sp. had the attachment disc angled toward the substratum, whereas it faces distally in cyprids from hard bottom inhabiting barnacles. We suggest that both velum/skirt and the angle of the attachment disc play an important role, when the antennules are contacting the substratum during surface exploration. Differences in attachment organ structures may be highly adaptive, enabling cirripede species to enter new habitats during evolution. J. Morphol. 277:594–602, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
85.
Jens G. P. Diller Sophia Drescher Mario Hofmann Max Rabus Heike Feldhaar Christian Laforsch 《Ecology and evolution》2022,12(4)
Invasive alien species are a major threat to ecosystems. Invasive terrestrial plants can produce allelochemicals which suppress native terrestrial biodiversity. However, it is not known if leached allelochemicals from invasive plants growing in riparian zones, such as Impatiens glandulifera, also affect freshwater ecosystems. We used mesocosms and laboratory experiments to test the impact of I. glandulifera on a simplified freshwater food web. Our mesocosm experiments show that leachate from I. glandulifera significantly reduced population growth rate of the water flea Daphnia magna and the green alga Acutodesmus obliquus, both keystone species of lakes and ponds. Laboratory experiments using the main allelochemical released by I. glandulifera, 2‐methoxy‐1,4‐naphthoquinone, revealed negative fitness effects in D. magna and A. obliquus. Our findings show that allelochemicals from I. glandulifera not only reduce biodiversity in terrestrial habitats but also pose a threat to freshwater ecosystems, highlighting the necessity to incorporate cross‐ecosystem effects in the risk assessment of invasive species. 相似文献
86.
Anja W. Fjorback Patrick Pla Heidi K. Müller Frédéric Saudou Jens R. Nyengaard 《Biochemical and biophysical research communications》2009,380(4):724-728
The serotonin transporter is a member of the monoamine transporter family that also includes transporters of dopamine and norepinephrine. We have used sensitized acceptor emission fluorescence resonance energy transfer (FRET) and fluorescence lifetime imaging microscopy (FLIM) to study the oligomerization of SERT in HEK-MSR-239 cells, RN46A cells and in cultured hippocampal neurons. We were able to show identical FRET efficiencies in cell lines as well as in primary cultured hippocampal neurons, demonstrating that the oligomerization is cell type independent. The results obtained with both FRET approaches are very similar and furthermore, in agreement with previous results obtained by donor bleaching FRET microscopy. 相似文献
87.
Shinichi Sunagawa Jens Roat Kultima Paul I Costea Aurélien Amiot Jürgen Böhm Francesco Brunetti Nina Habermann Rajna Hercog Moritz Koch Alain Luciani Daniel R Mende Martin A Schneider Petra Schrotz‐King Christophe Tournigand Jeanne Tran Van Nhieu Takuji Yamada Jürgen Zimmermann Vladimir Benes Matthias Kloor Cornelia M Ulrich Magnus von Knebel Doeberitz Iradj Sobhani Peer Bork 《Molecular systems biology》2014,10(11)
Several bacterial species have been implicated in the development of colorectal carcinoma (CRC),
but CRC-associated changes of fecal microbiota and their potential for cancer screening remain to be
explored. Here, we used metagenomic sequencing of fecal samples to identify taxonomic markers that
distinguished CRC patients from tumor-free controls in a study population of 156 participants.
Accuracy of metagenomic CRC detection was similar to the standard fecal occult blood test (FOBT) and
when both approaches were combined, sensitivity improved > 45% relative to the FOBT,
while maintaining its specificity. Accuracy of metagenomic CRC detection did not differ
significantly between early- and late-stage cancer and could be validated in independent patient and
control populations (N = 335) from different countries. CRC-associated
changes in the fecal microbiome at least partially reflected microbial community composition at the
tumor itself, indicating that observed gene pool differences may reveal tumor-related
host–microbe interactions. Indeed, we deduced a metabolic shift from fiber degradation in
controls to utilization of host carbohydrates and amino acids in CRC patients, accompanied by an
increase of lipopolysaccharide metabolism. 相似文献
88.
Milbradt J Auerochs S Sevvana M Muller YA Sticht H Marschall M 《The Journal of biological chemistry》2012,287(28):24004-24016
Herpesviral capsids are assembled in the host cell nucleus and are subsequently translocated to the cytoplasm. During this process it has been demonstrated that the human cytomegalovirus proteins pUL50 and pUL53 interact and form, together with other viral and cellular proteins, the nuclear egress complex at the nuclear envelope. In this study we provide evidence that specific residues of a conserved N-terminal region of pUL50 determine its intranuclear interaction with pUL53. In silico evaluation and biophysical analyses suggested that the conserved region forms a regular secondary structure adopting a globular fold. Importantly, site-directed replacement of individual amino acids by alanine indicated a strong functional influence of specific residues inside this globular domain. In particular, mutation of the widely conserved residues Glu-56 or Tyr-57 led to a loss of interaction with pUL53. Consistent with the loss of binding properties, mutants E56A and Y57A showed a defective function in the recruitment of pUL53 to the nuclear envelope in expression plasmid-transfected and human cytomegalovirus-infected cells. In addition, in silico analysis suggested that residues 3-20 form an amphipathic α-helix that appears to be conserved among Herpesviridae. Point mutants revealed a structural role of this N-terminal α-helix for pUL50 stability rather than a direct role in the binding of pUL53. In contrast, the central part of the globular domain including Glu-56 and Tyr-57 is directly responsible for the functional interaction with pUL53 and thus determines formation of the basic nuclear egress complex. 相似文献
89.
Vera R?tzer Andreas Breit Jens Waschke Volker Spindler 《The Journal of biological chemistry》2014,289(21):14925-14940
Adducin is a protein organizing the cortical actin cytoskeleton and a target of RhoA and PKC signaling. However, the role for intercellular cohesion is unknown. We found that adducin silencing induced disruption of the actin cytoskeleton, reduced intercellular adhesion of human keratinocytes, and decreased the levels of the desmosomal adhesion molecule desmoglein (Dsg)3 by reducing its membrane incorporation. Because loss of cell cohesion and Dsg3 depletion is observed in the autoantibody-mediated blistering skin disease pemphigus vulgaris (PV), we applied antibody fractions of PV patients. A rapid phosphorylation of adducin at serine 726 was detected in response to these autoantibodies. To mechanistically link autoantibody binding and adducin phosphorylation, we evaluated the role of several disease-relevant signaling molecules. Adducin phosphorylation at serine 726 was dependent on Ca2+ influx and PKC but occurred independent of p38 MAPK and PKA. Adducin phosphorylation is protective, because phosphorylation-deficient mutants resulted in loss of cell cohesion and Dsg3 fragmentation. Thus, PKC elicits both positive and negative effects on cell adhesion, since its contribution to cell dissociation in pemphigus is well established. We additionally evaluated the effect of RhoA on adducin phosphorylation because RhoA activation was shown to block pemphigus autoantibody-induced cell dissociation. Our data demonstrate that the protective effect of RhoA activation was dependent on the presence of adducin and its phosphorylation at serine 726. These experiments provide novel mechanisms for regulation of desmosomal adhesion by RhoA- and PKC-mediated adducin phosphorylation in keratinocytes. 相似文献
90.
Deletion of the substituted pyrimidine ring in purine-2'-deoxynucleoside 5'-monophosphates leads to the artificial nucleotide analog dImMP(2-) . This analog can be incorporated into DNA to yield, upon addition of Ag(+) ions, a molecular wire. Here, we measured the acidity constants of H(2) (dImMP)(±) having one proton at N(3) and one at the PO$\rm{{_{3}^{2-}}}$ group by potentiometric pH titrations in aqueous solution. The micro acidity constants show that N(3) is somewhat more basic than PO$\rm{{_{3}^{2-}}}$ and, consequently, the (H??dImMP)(-) tautomer with the proton at N(3) dominates to ca. 75%. The calculated micro acidity constants are confirmed by (31) P- and (1) H-NMR chemical shifts. The assembled data allow many quantitative comparisons, e.g., the N(3)-protonated and thus positively charged imidazole residue facilitates deprotonation of the P(O)(2) (OH)(-) group by 0.3?pK units. Information on the intrinsic site basicities also allows predictions about metal-ion binding; e.g., Mg(2+) and Mn(2+) will primarily coordinate to the phosphate group, whereas Ni(2+) and Cu(2+) will preferably bind to N(3). Macrochelate formation for these metal ions is also predicted. The micro acidity constant for N(3)H(+) deprotonation in the (H???dImMP?H)(±) species (pk(a) 6.46) and the M(n+) -binding properties are of relevance for understanding the behavior of dImMP units present in DNA hairpins and metalated duplexes. 相似文献