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951.
Emilie Montellier Fay?al Boussouar Sophie Rousseaux Kai Zhang Thierry Buchou Fran?ois Fenaille Hitoshi Shiota Alexandra Debernardi Patrick Héry Sandrine Curtet Mahya Jamshidikia Sophie Barral Hélène Holota Aurélie Bergon Fabrice Lopez Philippe Guardiola Karin Pernet Jean Imbert Carlo Petosa Minjia Tan Yingming Zhao Matthieu Gérard Saadi Khochbin 《Genes & development》2013,27(15):1680-1692
The conversion of male germ cell chromatin to a nucleoprotamine structure is fundamental to the life cycle, yet the underlying molecular details remain obscure. Here we show that an essential step is the genome-wide incorporation of TH2B, a histone H2B variant of hitherto unknown function. Using mouse models in which TH2B is depleted or C-terminally modified, we show that TH2B directs the final transformation of dissociating nucleosomes into protamine-packed structures. Depletion of TH2B induces compensatory mechanisms that permit histone removal by up-regulating H2B and programming nucleosome instability through targeted histone modifications, including lysine crotonylation and arginine methylation. Furthermore, after fertilization, TH2B reassembles onto the male genome during protamine-to-histone exchange. Thus, TH2B is a unique histone variant that plays a key role in the histone-to-protamine packing of the male genome and guides genome-wide chromatin transitions that both precede and follow transmission of the male genome to the egg. 相似文献
952.
Chantal Bottex Yves P. Gauthier Ralf M. Hagen Ernst J. Finke Wolf D. Splettstösser François M. Thibault 《Immunopharmacology and immunotoxicology》2013,35(4):565-583
Melioidosis is a severe gram-negative infection caused by the facultative intracellular bacterium Burkholderia pseudomallei, which is responsible for a broad spectrum of symptoms in both humans and animals. No licensed vaccine currently exists. This study evaluated the protective effect of a monoclonal antibody (Mab Ps6F6) specific to B. pseudomallei exopolysaccharide in an outbred murine model of sub-acute melioidosis. When administered before the infectious challenge, Ps6F6 significantly increased resistance to infection and restrained bacterial burden in the spleen over a 30-days period. Patterns of IFN-γ production were similar in the treated and non treated groups of mice. However, Ps6F6 lowered IFN-γ levels over the duration of the assay period, except on day 1, suggesting a transient and rapid production of IFN-γ under Ps6F6 control. Minor but persisting increases occurred in IL-12 levels while TNF-α was detected only in the controls at the later stages of infection. No IL-10 secretion was detected in both groups of mice. These data suggest that passive prophylaxis with Mab Ps6F6 provide a moderate and transient induction of inflammatory responses in infected mice but failed to trigger a sterilizing protective immunity. 相似文献
953.
Zülfikar Temoçin 《Journal of biomaterials science. Polymer edition》2013,24(14):1618-1635
This study focuses on Candida rugosa lipase (CRL) immobilization by covalent attachment on poly(ethylene terephthalate)-grafted glycidyl methacrylate (PET-g-GMA) fiber. The immobilization yielded a protein loading of 2.38?mg?g-1 of PET-g-GMA fiber. The performances of the immobilized and free CRLs were evaluated with regard to hydrolysis of olive oil and esterification of oleic acid. The optimum activity pH of the CRL was changed by immobilization to neutral range. The maximum activity of the free and immobilized CRLs occurred at 40 and 45?°C respectively. The immobilized lipase retained 65% of its original activity at 50?°C for 2?h. It was found that the immobilized lipase stored at 4?°C retained 90% of its original activity after 35?days, whereas the free lipase stored at 4?°C retained 69% of its original activity after the same period. In the esterification experiments, the immobilized CRL could maintain a high activity at a water content range from 1.5 to 6% (v/v), while the activity of free CRL showed a clear dependence on water content and decreased rapidly at above 3% (v/v) water content. In addition, after five reuses, the esterification percent yield of the immobilized CRL slightly decreased from 29 to 27%. 相似文献
954.
Menemşe Gümüşderelioğlu Soner Çakmak H. Özgen Timuçin Anıl S. Çakmak 《Journal of biomaterials science. Polymer edition》2013,24(18):2110-2125
In this study, we developed a novel microcarrier to enhance the production of anchorage-dependent mammalian cells in large scale by preserving them from the effects of shear forces and to enhance their removal from the surface without using proteolytic enzymes and chelating agents. This ‘thermosensitive microcarrier’ was synthesized by the grafting thermoresponsive molecule, N-isopropylacrylamide (NIPAAm), to the crosslinked poly(2-hydroxyethyl methacrylate) (PHEMA) beads by surface-initiated atom transfer radical polymerization. NIPAAm was polymerized on bromine-activated beads’ surfaces to prepare PHEMA-g-PNIPAAm microcarriers. Then, they were chemically characterized by attenuated total reflectance Fourier transform infrared and electron spectroscopy for chemical analysis. Surface morphologies were further investigated by scanning electron microscope and atomic force microscopy techniques. The results of characterization studies confirmed that PNIPAAm was successfully grafted onto PHEMA beads by the means of atom transfer radical polymerization reaction. The cellular activities of PHEMA-g-PNIPAAm microcarriers were evaluated at static and dynamic culture conditions by using two types of cell lines with different morphology, i.e. L929 mouse fibroblasts and HS2 epithelial human keratinocytes. The microcarriers exhibited better cell adhesion and proliferation characteristics for both cell lines. Although their thermally induced cell detachment efficiencies are lower than that of trypsinization, thermally harvested cells preserved their surface morphologies and proliferation characteristics. 相似文献
955.
956.
Erica Aranha Suzumura Layse Martins Gama Beate Jahn Alessandro Gonçalves Campolina Heloisa de Andrade Carvalho Patrícia Coelho de Soárez 《Brachytherapy》2021,20(4):710-737
PURPOSETo assess the effects of three-dimensional image-guided brachytherapy (3D BT) compared to bi-dimensional BT (2D BT) on clinical outcomes in patients with cervical cancer.METHODS AND MATERIALSWe searched PubMed/MEDLINE, EMBASE, Scopus, CENTRAL, Web of Science, and LILACS for studies assessing the effects of 3D BT versus 2D BT on clinical outcomes. Two reviewers independently screened retrieved citations, extracted data and assessed risk of bias from eligible studies. Hazard ratios (HR) were calculated from Kaplan-Meier curves considering the number of events, their timing and the followup of censored patients. We conducted meta-analyses of HR using the inverse-variance random-effects method. Risk Difference (RD) for toxicities were pooled using the Mantel–Haenszel random-effects method. We used the GRADE system to rate the certainty of evidence.RESULTSTwenty observational studies involving 4287 patients were included. The meta-analyses assessing the effect of 3D BT versus 2D BT on overall survival resulted in a HR of 0.78 (95%CI 0.62–0.98), HR of 0.75 (95%CI 0.62–0.90) for pelvic disease-free survival, HR of 0.93 (95%CI 0.81–1.06) for metastatic disease-free survival, and HR of 0.77 (95%CI 0.59–0.99) for local control. Grade 3–4 global and gastrointestinal toxicities were, respectively, 9% lower (95%CI 6% to 11%) and 5% lower (95%CI 2% to 8%) in patients receiving 3D BT versus 2D BT. Certainty of evidence was very low for all assessed outcomes.CONCLUSIONSOur study may suggest a benefit of 3D BT over conventional 2D BT on important clinical outcomes. 相似文献
957.
Minkwan Kim Seung-Pyo Lee Soongu Kwak Seokhun Yang Yong-Jin Kim Daniele Andreini Mouaz H. Al-Mallah Matthew J. Budoff Filippo Cademartiri Kavitha Chinnaiyan Jung Hyun Choi Edoardo Conte Hugo Marques Pedro de Araújo Gonçalves Ilan Gottlieb Martin Hadamitzky Jonathon A. Leipsic Erica Maffei Hyuk-Jae Chang 《Journal of Cardiovascular Computed Tomography》2021,15(3):232-239
BackgroundThe association of age with coronary plaque dynamics is not well characterized by coronary computed tomography angiography (CCTA).MethodsFrom a multinational registry of patients who underwent serial CCTA, 1153 subjects (61 ± 5 years old, 61.1% male) were analyzed. Annualized volume changes of total, fibrous, fibrofatty, necrotic core, and dense calcification plaque components of the whole heart were compared by age quartile groups. Clinical events, a composite of all-cause death, acute coronary syndrome, and any revascularization after 30 days of the initial CCTA, were also analyzed. Random forest analysis was used to define the relative importance of age on plaque progression.ResultsWith a 3.3-years’ median interval between the two CCTA, the median annual volume changes of total plaque in each age quartile group was 7.8, 10.5, 10.8, and 12.1 mm3/year and for dense calcification, 2.5, 4.6, 5.4, and 7.1 mm3/year, both of which demonstrated a tendency to increase by age (p-for-trend = 0.001 and < 0.001, respectively). However, this tendency was not observed in any other plaque components. The annual volume changes of total plaque and dense calcification were also significantly different in the propensity score-matched lowest age quartile group versus the other age groups as was the composite clinical event (log-rank p = 0.003). In random forest analysis, age had comparable importance in the total plaque volume progression as other traditional factors.ConclusionsThe rate of whole-heart plaque progression and dense calcification increases depending on age. Age is a significant factor in plaque growth, the importance of which is comparable to other traditional risk factors.Clinical trial registrationURL: http://www.clinicaltrials.gov. Unique identifiers: NCT02803411. 相似文献
958.
Ba Khadija Casolla Barbara Caparros François Bricout Nicolas Della Schiava Lucie Pasi Marco Dequatre-Ponchelle Nelly Bodenant Marie Bordet Régis Cordonnier Charlotte Hénon Hilde Leys Didier 《Journal of neurology》2021,268(1):305-311
Journal of Neurology - The epileptogenicity of recombinant tissue-plasminogen activator (rt-PA) has been suggested, but seizures were not evaluated in randomised controlled trials. To evaluate... 相似文献
959.
Ravel Jean-Marie Benkirane Mehdi Calmels Nadège Marelli Cecilia Ory-Magne Fabienne Ewenczyk Claire Halleb Yosra Tison François Lecocq Claire Pische Guillaume Casenave Philippe Chaussenot Annabelle Frismand Solène Tyvaert Louise Larrieu Lise Pointaux Morgane Drouot Nathalie Bossenmeyer-Pourié Carine Oussalah Abderrahim Guéant Jean-Louis Leheup Bruno Bonnet Céline Anheim Mathieu Tranchant Christine Lambert Laëtitia Chelly Jamel Koenig Michel Renaud Mathilde 《Journal of neurology》2021,268(5):1927-1937
Journal of Neurology - STUB1 has been first associated with autosomal recessive (SCAR16, MIM# 615768) and later with dominant forms of ataxia (SCA48, MIM# 618093). Pathogenic variations in STUB1... 相似文献
960.
J. Cornillon M.-C. Vantyghem M.A. Couturier E. de Berranger S. François E. Hermete N. Maillard A. Marcais R. Tabrizi C. Decanter R. Duléry F. Bauters I. Yakoub-Agha 《Pathologie-biologie》2013
In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC) set up the third annual series of workshops which brought together practitioners from all member centers and took place in October 2012 in Lille. Here we report our results and recommendations regarding the management of short and long-term endocrine dysfunction following allogeneic stem cell transplantation. The key aim of this workshop was to give an overview on secondary adrenal insufficiency and osteoporosis post-transplant. 相似文献