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41.
Hajer Khemaissia Maryline Raimond Anas Ayari Raja Jelassi Catherine Souty-Grosset Karima Nasri-Ammar 《Biologia》2018,73(5):477-483
Terrestrial isopods have adapted to land life by diverse morphological, physiological and behavioral changes. Isopod species exhibit a large variety of preferences ranging from moist to dry habitats. Isopod cuticle is an interesting model for studying adaptations to terrestrial life. The cuticle consists of a hierarchically organized material which provides protection and sites for muscle attachment. The present paper aimed to investigate the structure of the cuticle in three isopod species in order to relate some peculiar features to an adaptive process to environmental constraints. Results showed that general thickness of Ligia italica cuticle was quite similar to that observed in Porcellio lamellatus. Nevertheless, this cuticle was half as thick as in Porcellio laevis. Although the positive relationship found between total body lengths and the total thickness of the cuticle, the exocuticle did not show any differences between the three species. However, it is the development of a thicker endocuticle in P. laevis which make its total cuticle thickness more important. 相似文献
42.
John O'Quigley Ronghui Xu Patrick Blin Yves Charpak 《Biometrical journal. Biometrische Zeitschrift》1999,41(7):773-782
In this paper we investigate ways in which the results of a controlled Phase III clinical trial can be used in subsequent Phase IV, and possibly further Phase III studies. Specifically we are interested in; 1) developing particular hypothesis relating to a modified study population, 2) studying how changes in the particularities of the Phase III study group can influence certain outcome variables of interest and 3) using the results of the Phase III study applied to specific target groups, having particular characteristics, to updating observations from the Phase III study with information obtained at a later stage. These issues are all concerned with the way in which we can exploit information from a Phase III trial, information that is of high quality but not necessarily directly related to the way in which many post Phase III studies, focussing on different patient population groups, are carried out. Since it is often these post Phase III studies that have the strongest influence on clinical practice we aim to develop a framework around which the post Phase III studies might be structured. 相似文献
43.
Desbois N Gardette M Papon J Labarre P Maisonial A Auzeloux P Lartigue C Bouchon B Debiton E Blache Y Chavignon O Teulade JC Maublant J Madelmont JC Moins N Chezal JM 《Bioorganic & medicinal chemistry》2008,16(16):7671-7690
Various iodo-acridone and acridine carboxamides have been prepared and evaluated as agents for targeted radionuclide and/or chemotherapy for melanoma, due to their structural similarity to benzamides which are known to possess specific affinity for melanin. Three of these carboxamides selected for their in vitro cytotoxic properties were radioiodinated with [(125)I]NaI at high specific activity. Biodistribution studies carried out in B16F0 murine melanoma tumour-bearing mice highlighted that acridone 8f and acridine 9d, presented high, long-lasting tumour concentrations together with an in vivo kinetic profile favourable to application in targeted radionuclide therapy. 相似文献
44.
Maryline Couette Marie-Franoise Boisse Patrick Maison Pierre Brugieres Pierre Cesaro Xavier Chevalier Romain K. Gherardi Anne-Catherine Bachoud-Levi Franois-Jrme Authier 《Journal of inorganic biochemistry》2009,103(11):1571-1578
Macrophagic myofasciitis (MMF) is an emerging condition, characterized by specific muscle lesions assessing long-term persistence of aluminum hydroxide within macrophages at the site of previous immunization. Affected patients mainly complain of arthromyalgias, chronic fatigue, and cognitive difficulties. We designed a comprehensive battery of neuropsychological tests to prospectively delineate MMF-associated cognitive dysfunction (MACD). Compared to control patients with arthritis and chronic pain, MMF patients had pronounced and specific cognitive impairment. MACD mainly affected (i) both visual and verbal memory; (ii) executive functions, including attention, working memory, and planning; and (iii) left ear extinction at dichotic listening test. Cognitive deficits did not correlate with pain, fatigue, depression, or disease duration. Pathophysiological mechanisms underlying MACD remain to be determined. In conclusion, long-term persistence of vaccine-derived aluminum hydroxide within the body assessed by MMF is associated with cognitive dysfunction, not solely due to chronic pain, fatigue and depression. 相似文献
45.
46.
Peter Geserick Mike Hupe Maryline Moulin W. Wei-Lynn Wong Maria Feoktistova Beate Kellert Harald Gollnick John Silke Martin Leverkus 《The Journal of cell biology》2009,187(7):1037-1054
A role for cellular inhibitors of apoptosis (IAPs [cIAPs]) in preventing CD95 death has been suspected but not previously explained mechanistically. In this study, we find that the loss of cIAPs leads to a dramatic sensitization to CD95 ligand (CD95L) killing. Surprisingly, this form of cell death can only be blocked by a combination of RIP1 (receptor-interacting protein 1) kinase and caspase inhibitors. Consistently, we detect a large increase in RIP1 levels in the CD95 death-inducing signaling complex (DISC) and in a secondary cytoplasmic complex (complex II) in the presence of IAP antagonists and loss of RIP1-protected cells from CD95L/IAP antagonist–induced death. Cells resistant to CD95L/IAP antagonist treatment could be sensitized by short hairpin RNA–mediated knockdown of cellular FLICE-inhibitory protein (cFLIP). However, only cFLIPL and not cFLIPS interfered with RIP1 recruitment to the DISC and complex II and protected cells from death. These results demonstrate a fundamental role for RIP1 in CD95 signaling and provide support for a physiological role of caspase-independent death receptor–mediated cell death. 相似文献
47.
48.
Genesis of muscle fiber-type diversity during mouse embryogenesis relies on Six1 and Six4 gene expression 总被引:1,自引:0,他引:1
49.
Zhu R Mancini-Bourgine M Zhang XM Bayard F Deng Q Michel ML 《Journal of virology》2011,85(19):10201-10212
Plasmid DNA vaccines serve in a wide array of applications ranging from prophylactic vaccines to potential therapeutic tools against infectious diseases and cancer. In this study, we analyzed the mechanisms underlying the activation of natural killer (NK) cells and their potential role in adaptive immunity during DNA-based immunization against hepatitis B virus surface antigen in mice. We observed that the mature Mac-1(+) CD27(-) NK cell subset increased in the liver of mice early after DNA injection, whereas the number of the less mature Mac-1(+) CD27(+) NK cells in the liver and spleen was significantly reduced. This effect was attributed to bacterial sequences present in the plasmid backbone rather than to the encoded antigen and was not observed in immunized MyD88-deficient mice. The activation of NK cells by plasmid-DNA injection was associated with an increase in their effector functions that depended on the expressed antigen. Maturation of NK cells was abrogated in the absence of T cells, suggesting that cross talk exists between NK cells and antigen-specific T cells. Taken together, our data unravel the mechanics of plasmid vector-induced maturation of NK cells and plasmid-encoded antigen-dependent activation of NK cells required for a crucial role of NK cells in DNA vaccine-induced immunogenicity. 相似文献
50.
Vitor C. Pacheco da Silva Aline Bertin Aurélie Blin Jean-Fran?ois Germain Daniel Bernardi Guylène Rignol Marcos Botton Thibaut Malausa 《PloS one》2014,9(7)
Mealybugs (Hemiptera: Pseudococcidae) are pests constraining the international trade of Brazilian table grapes. They damage grapes by transmitting viruses and toxins, causing defoliation, chlorosis, and vigor losses and favoring the development of sooty mold. Difficulties in mealybug identification remain an obstacle to the adequate management of these pests. In this study, our primary aim was to identify the principal mealybug species infesting the major table grape-producing regions in Brazil, by morphological and molecular characterization. Our secondary aim was to develop a rapid identification kit based on species-specific Polymerase Chain Reactions, to facilitate the routine identification of the most common pest species. We surveyed 40 sites infested with mealybugs and identified 17 species: Dysmicoccus brevipes (Cockerell), Dysmicoccus sylvarum Williams and Granara de Willink, Dysmicoccus texensis (Tinsley), Ferrisia cristinae Kaydan and Gullan, Ferrisia meridionalis Williams, Ferrisia terani Williams and Granara de Willink, Phenacoccus baccharidis Williams, Phenacoccus parvus Morrison, Phenacoccus solenopsis Tinsley, Planococcus citri (Risso), Pseudococcus viburni (Signoret), Pseudococcus cryptus Hempel, four taxa closely related each of to Pseudococcus viburni, Pseudococcus sociabilis Hambleton, Pseudococcus maritimus (Ehrhorn) and Pseudococcus meridionalis Prado, and one specimen from the genus Pseudococcus Westwood. The PCR method developed effectively identified five mealybug species of economic interest on grape in Brazil: D. brevipes, Pl. citri, Ps. viburni, Ph. solenopsis and Planococcus ficus (Signoret). Nevertheless, it is not possible to assure that this procedure is reliable for taxa that have not been sampled already and might be very closely related to the target species. 相似文献