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41.
Ann Van Campenhout Christel M. Van Campenhout Albert R. Lagrou Begoña Manuel-y-Keenoy 《Free radical research》2013,47(10):1069-1077
Free iron is capable of stimulating the production of free radicals which cause oxidative damage such as lipid peroxidation. One of the most important mechanisms of antioxidant defense is thus the sequestration of iron in a redox-inactive form by transferrin. In diabetes mellitus, increased oxidative stress and lipid peroxidation contribute to chronic complications but it is not known if this is related to abnormalities in transferrin function. In this study we investigated the role of transferrin concentration and glycation. The antioxidant capacity of apotransferrin to inhibit lipid peroxidation by iron-binding decreased in a concentration-dependent manner from 89% at <formula>≥2 mg/ml</formula> to 42% at 0.5 mg/ml. Pre-incubation of apotransferrin with glucose for 14 days resulted in a concentration-dependent increase of glycation: 1, 5 and 13 μmol fructosamine/g transferrin at 0, 5.6 and 33.3 mmol/l glucose respectively, p<0.001. This was accompanied by a decrease in the iron-binding antioxidant capacity of apotransferrin. In contrast, transferrin glycation by up to 33.3 mmol/l glucose did not affect chemiluminescence-quenching antioxidant capacity, which is iron-independent. Colorimetric evaluation of total iron binding capacity in the presence of an excess of iron (iron/transferrin molar ratio=2.4) also decreased from 0.726 to 0.696 and 0.585 mg/g transferrin after 0, 5.6 and 33.3 mmol/l glucose, respectively, p<0.01. In conclusion, these results suggest that lower transferrin concentration and its glycation can, by enhancing the pro-oxidant effects of iron, contribute to the increased lipid peroxidation observed in diabetes. 相似文献
42.
Fenge Christel Klein Cornelia Heuer Carsten Siegel Ursula Fraune Elisabeth 《Cytotechnology》1993,11(3):233-244
For an optimized bioreactor design which is adapted to the cultivation of sensitive animal cells different modular bioreactor components for gentle agitation, sufficient aeration and long-term perfusion were developed and investigated with respect to their suitability from laboratory to production scale. Aeration systems have been designed for both shear sensitive cells and cells which tolerate bubbles. The systems are based on either membranes for bubble-free aeration or stainless steel sparger systems. They were characterized by determination of their oxygen transfer capacity and optimized in cultivation processes of different cell lines under process conditions such as batch and perfusion mode.Different impellers for suspension cells and cells grown on carriers were investigated for their suitability to ensure homogeneous gentle mixing. A large pitch blade impeller as well as a novel 3-blade segment impeller are appropriate for homogeneous mixing at low shear rates. Especially with the 3-blade segment impeller fluid mechanical stress can be reduced at a given stirrer speed which is advantageous for the cultivation of cells attached to microcarriers or extremely shear sensitive suspension cells. However, our results indicate that shear sensitivity of animal cells has been generally overestimated.Continuous perfusion of both suspension cell cultures and cells cultivated on microcarriers could be successfully performed over extended periods of time using stainless steel spinfilters with appropriate pore sizes and systems based on microporous hydrophilic membranes. Spinfilters are suitable cell retention systems for technical scale bioreactors allowing continuous perfusion cultures of suspension cells (pore size 10 to 20 m) as well as anchorage dependent cells grown on microcarriers (pore size 75 m) over six weeks to 3 months.Applying the developed modules for agitation, aeration and perfusion process adapted bioreactor set-ups can be realized which ensure optimum growth and product formation conditions in order to maximize cell and product yields. 相似文献
43.
Tandem repeats represent one of the most abundant class of variations in human genomes, which are polymorphic by nature and become highly unstable in a length-dependent manner. The expansion of repeat length across generations is a well-established process that results in human disorders mainly affecting the central nervous system. At least 50 disorders associated with expansion loci have been described to date, with half recognized only in the last ten years, as prior methodological difficulties limited their identification. These limitations still apply to the current widely used molecular diagnostic methods (exome or gene panels) and thus result in missed diagnosis detrimental to affected individuals and their families, especially for disorders that are very rare and/or clinically not recognizable. Most of these disorders have been identified through family-driven approaches and many others likely remain to be identified. The recent development of long-read technologies provides a unique opportunity to systematically investigate the contribution of tandem repeats and repeat expansions to the genetic architecture of human disorders. In this review, we summarize the current and most recent knowledge about the genetics of repeat expansion disorders and the diversity of their pathophysiological mechanisms and outline the perspectives of developing personalized treatments in the future.Tandem repeats represent one of the most abundant class of variations in human genomes, which are polymorphic by nature and become highly unstable in a length-dependent manner. The expansion of repeat length across generations is a well-established process that results in human disorders mainly affecting the central nervous system. At least 50 disorders associated with expansion loci have been described to date, with half recognized only in the last ten years, as prior methodological difficulties limited their identification. These limitations still apply to the current widely used molecular diagnostic methods (exome or gene panels) and thus result in missed diagnosis detrimental to affected individuals and their families, especially for disorders that are very rare and/or clinically not recognizable. Most of these disorders have been identified through family-driven approaches and many others likely remain to be identified. The recent development of long-read technologies provides a unique opportunity to systematically investigate the contribution of tandem repeats and repeat expansions to the genetic architecture of human disorders. In this review, we summarize the current and most recent knowledge about the genetics of repeat expansion disorders and the diversity of their pathophysiological mechanisms and outline the perspectives of developing personalized treatments in the future. 相似文献
44.
Dr. Christel Hintze 《Zoomorphology》1969,64(1):1-8
The larvae of Cerura vinula L. and Notodonta anceps Goeze secrete formic acid for defence. The glandular protective system which forms the acid and changes of the cell structure were studied with the light-microscope.
Mit dankenswerter Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Mit dankenswerter Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
45.
Christel Thauvin-Robinet Martine Auclair Laurence Duplomb Martine Caron-Debarle Magali Avila Judith St-Onge Martine Le?Merrer Bernard Le?Luyer Delphine Héron Michèle Mathieu-Dramard Pierre Bitoun Jean-Michel Petit Sylvie Odent Jeanne Amiel Damien Picot Virginie Carmignac Julien Thevenon Patrick Callier Martine Laville Yves Reznik Cédric Fagour Marie-Laure Nunes Jacqueline Capeau Olivier Lascols Frédéric Huet Laurence Faivre Corinne Vigouroux Jean-Baptiste Rivière 《American journal of human genetics》2013,93(1):141-149
Short stature, hyperextensibility of joints and/or inguinal hernia, ocular depression, Rieger anomaly, and teething delay (SHORT) syndrome is a developmental disorder with an unknown genetic cause and hallmarks that include insulin resistance and lack of subcutaneous fat. We ascertained two unrelated individuals with SHORT syndrome, hypothesized that the observed phenotype was most likely due to de novo mutations in the same gene, and performed whole-exome sequencing in the two probands and their unaffected parents. We then confirmed our initial observations in four other subjects with SHORT syndrome from three families, as well as 14 unrelated subjects presenting with syndromic insulin resistance and/or generalized lipoatrophy associated with dysmorphic features and growth retardation. Overall, we identified in nine affected individuals from eight families de novo or inherited PIK3R1 mutations, including a mutational hotspot (c.1945C>T [p.Arg649Trp]) present in four families. PIK3R1 encodes the p85α, p55α, and p50α regulatory subunits of class IA phosphatidylinositol 3 kinases (PI3Ks), which are known to play a key role in insulin signaling. Functional data from fibroblasts derived from individuals with PIK3R1 mutations showed severe insulin resistance for both proximal and distal PI3K-dependent signaling. Our findings extend the genetic causes of severe insulin-resistance syndromes and provide important information with respect to the function of PIK3R1 in normal development and its role in human diseases, including growth delay, Rieger anomaly and other ocular affections, insulin resistance, diabetes, paucity of fat, and ovarian cysts. 相似文献
46.
Christian Pedersen Anatoly Slepenkin Sara B. E. Andersson Jonas H. Fagerberg Christel A. S. Bergstr?m Ellena M. Peterson 《PloS one》2014,9(10)
The salicylidene acylhydrazide (SA) compounds have exhibited promising microbicidal properties. Previous reports have shown the SA compounds, using cell cultures, to exhibit activity against Chlamydia trachomatis, herpes simplex virus and HIV-1. In addition, using an animal model of a vaginal infection the SA compound INP0341, when dissolved in a liquid, was able to significantly protect mice from a vaginal infection with C. trachomatis. To expand upon this finding, in this report INP0341 was formulated as a vaginal gel, suitable for use in humans. Gelling agents (polymers) with inherent antimicrobial properties were chosen to maximize the total antimicrobial effect of the gel. In vitro formulation work generated a gel with suitable rheology and sustained drug release. A formulation containing 1 mM INP0341, 1.6 wt% Cremophor ELP (solubility enhancer) and 1.5 wt% poly(acrylic acid) (gelling and antimicrobial agent), was chosen for studies of efficacy and toxicity using a mouse model of a vaginal infection. The gel formulation was able to attenuate a vaginal challenge with C. trachomatis, serovar D. Formulations with and without INP0341 afforded protection, but the inclusion of INP0341 increased the protection. Mouse vaginal tissue treated with the formulation showed no indication of gel toxicity. The lack of toxicity was confirmed by in vitro assays using EpiVaginal tissues, which showed that a 24 h exposure to the gel formulation did not decrease the cell viability or the barrier function of the tissue. Therefore, the gel formulation described here appears to be a promising vaginal microbicide to prevent a C. trachomatis infection with the potential to be expanded to other sexually transmitted diseases. 相似文献
47.
Marta Tischer Michał Gorczak Błażej Bojarski Julia Pawłowska Christel Hoffeins Hans Werner Hoffeins Marta Wrzosek 《Fungal biology》2019,123(11):804-810
Three new fossils of saprotrophic fungi are presented and described from Baltic amber, dated to Eocene epoch (Paleogene, upper to mid-Eocene). All belong to Ascomycota and are represented by hyphae as well as asexual reproduction structures allowing to assign them to present genera, respectively Periconia, Penicillium and Scopulariopsis. These material provide both the first and the oldest known fossil record of the mentioned taxa, making these data valuable for the knowledge about the evolutionary history of the Ascomycota. 相似文献
48.
Schann S Menet C Arvault P Mercier G Frauli M Mayer S Hubert N Triballeau N Bertrand HO Acher F Neuville P 《Bioorganic & medicinal chemistry letters》2006,16(18):4856-4860
A new family of mGlu receptor orthosteric ligands called APTCs was designed and synthesized using a parallel chemistry approach. Amongst 65 molecules tested on mGlu4, mGlu6 and mGlu8 subtypes, (2S,4S)-4-amino-1-[(E)-3-carboxyacryloyl]pyrrolidine-2,4-dicarboxylic acid (8a06-FP0429) has been shown to be a full mGlu4 agonist and a partial mGlu8 agonist. In addition, 8a06 was shown to be selective versus group I and II mGlu subtypes. A possible explanation for this efficacy difference is proposed by docking experiment performed with molecular model of the receptor. 相似文献
49.
BACKGROUND: EURO-TELEPATH is a European COST Action IC0604. It started in 2007 and will end in November 2011. Its main objectives are evaluating and validating the common technological framework and communication standards required to access, transmit, and manage digital medical records by pathologists and other medical specialties in a networked environment. BUSINESS MODELLING: Working Group 1, "Business Modelling in Pathology," has designed main pathology processes - Frozen Study, Formalin Fixed Specimen Study, Telepathology, Cytology, and Autopsy - using Business Process Modelling Notation (BPMN). INFORMATICS STANDARDS IN PATHOLOGY: Working Group 2 has been dedicated to promoting the application of informatics standards in pathology, collaborating with Integrating Healthcare Enterprise (IHE), Digital Imaging and Communications in Medicine (DICOM), Health Level Seven (HL7), and other standardization bodies. CONCLUSIONS: Health terminology standardization research has become a topic of great interest. Future research work should focus on standardizing automatic image analysis and tissue microarrays imaging. 相似文献
50.
The early gesturing of six bonobos, eight chimpanzees, three gorillas, and eight orangutans was systematically documented using focal animal sampling. Apes' were observed during their first 20 months of life in an effort to investigate: (i) the onset of gesturing; (ii) the order in which signals of different sensory modalities appear; (iii) the extent to which infants make use of these modalities in their early signaling; and (iv) the behavioral contexts where signals are employed. Orangutans differed in important gestural characteristics to African ape species. Most notably, they showed the latest gestural onset and were more likely to use their early signals in food-related interactions. Tactile and visual signals appeared similarly early across all four species. In African apes, however, visual signaling gained prominence over time while tactile signaling decreased. These findings suggest that motor ability, which encourages independence from caregivers, is an important antecedent, among others, in gestural onset and development, a finding which warrants further investigation. 相似文献