26 research outputs found
Careful adjustment of Epo non-viral gene therapy for β-thalassemic anaemia treatment
BACKGROUND: In situ production of a secreted therapeutic protein is one of the major gene therapy applications. Nevertheless, the plasmatic secretion peak of transgenic protein may be deleterious in many gene therapy applications including Epo gene therapy. Epo gene transfer appears to be a promising alternative to recombinant Epo therapy for severe anaemia treatment despite polycythemia was reached in many previous studies. Therefore, an accurate level of transgene expression is required for Epo application safety. The aim of this study was to adapt posology and administration schedule of a chosen therapeutic gene to avoid this potentially toxic plasmatic peak and maintain treatment efficiency. The therapeutic potential of repeated muscular electrotransfer of light Epo-plasmid doses was evaluated for anaemia treatment in β-thalassemic mice. METHODS: Muscular electrotransfer of 1 μg, 1.5 μg, 2 μg 4 μg or 6 μg of Epo-plasmid was performed in β-thalassemic mice. Electrotransfer was repeated first after 3.5 or 5 weeks first as a initiating dose and then according to hematocrit evolution. RESULTS: Muscular electrotransfer of the 1.5 μg Epo-plasmid dose repeated first after 5 weeks and then every 3 months was sufficient to restore a subnormal hematrocrit in β-thalassemic mice for more than 9 months. CONCLUSION: This strategy led to efficient, long-lasting and non-toxic treatment of β-thalassemic mouse anaemia avoiding the deleterious initial hematocrit peak and maintaining a normal hematocrit with small fluctuation amplitude. This repeat delivery protocol of light doses of therapeutic gene could be applied to a wide variety of candidate genes as it leads to therapeutic effect reiterations and increases safety by allowing careful therapeutic adjustments
Does the shape of forelimb long bones co-vary with grasping behaviour in strepsirrhine primates?
Fine prehensile activities are often thought to have been associated with the evolution of the human hand. However, there has been no holistic approach establishing the link between the morphology of the forelimb and grasping ability in living primates. The present study investigated the possible relationships between grasping behaviour and the morphology of the forelimb in strepsirrhines in a phylogenetic context. To do so, grasping behaviour during feeding and the shape of the long bones of the forelimb were analysed for 22 species of strepsirrhines. The data obtained show that there is a phylogenetic signal in forelimb morphology in primates in relation to grasping behaviour, but also that there is a marked co-evolution between grasping behaviour and the shape of the humerus and radius. This latter finding suggests a functional association between grasping and forelimb shape, which in turn suggests that bone shape constrains or facilitates behaviour. This result may permit future inferences to be made regarding this behaviour in extinct species and deserves further examination in more detail
Evolutionary History of food Withdraw Movements in Primates: Food Withdraw is Mediated by Nonvisual Strategies in 22 Species of Strepsirrhines
Anthropoid vision contributes not only to reaching and grasping but also to the orienting of a food item during the withdraw movement to precisely place it in the mouth for eating. The evolutionary history of this visual control of feeding is not known. It likely evolved from the nonvisual control of the hand that is used with good effect for eating in many non-primate animal species. Strepsirrhines are a relatively large monophyletic group, diverging near the base of the primate cladogram, and described as using vision to reach for food. It is not known whether they use vision to orient food items during the withdraw movement. Video recordings of 7,464 withdraw movements from 22 species of captive strepsirrhines eating their normal food provisions were used to assess whether and how vision contributes to the withdraw movement. The constituent acts of withdraw movements, head orientation, body posture, ground-withdraw and inhand-withdraw, were assessed using frame-by-frame video inspection. Strepsirrhines were versatile in using their hands to get food to the mouth. They displayed variation between and within families that were weakly related to phylogenetic relationships and mainly related to feeding niches. There was no evidence that any species used vision to assist with the withdraw movement. Instead strepsirrhines used mouth reaching to take food from the hand and/or perioral contact to positioning food for biting. Our findings support two hypotheses: that visual mediation of food orienting for placement in the mouth during the withdraw movement is an anthropoid innovation, and that the evolution of the visual control of feeding was not a singular event
Nectin-4 is a new histological and serological tumor associated marker for breast cancer
International audienceIntroduction: Breast cancer is a complex and heterogeneous disease at the molecular level. Evolution is difficult to predict according to classical histoclinical prognostic factors. Different studies highlight the importance of large-scale molecular expression analyses to improve taxonomy of breast cancer and prognostic classification. Identification of new molecular markers that refine this taxonomy and improve patient management is a priority in the field of breast cancer research. Nectins are cell adhesion molecules involved in the regulation of epithelial physiology. We present here Nectin-4/PVRL4 as a new histological and serological tumor associated marker for breast carcinoma. Methods: Expression of Nectin-4 protein was measured on a panel of 78 primary cells and cell lines from different origins and 57 breast tumors by FACS analysis and immunohistochemistry (IHC), respectively. mRNA expression was measured by quantitative PCR. Serum Nectin-4 was detected by ELISA and compared with CEA and CA15.3 markers, on panels of 45 sera from healthy donors, 53 sera from patients with non-metastatic breast carcinoma (MBC) at diagnosis, and 182 sera from patients with MBC. Distribution of histological/serological molecular markers and histoclinical parameters were compared using the standard Chi-2 test. Results: Nectin-4 was not detected in normal breast epithelium. By contrast, Nectin-4 was expressed in 61% of ductal breast carcinoma vs 6% in lobular type. Expression of Nectin-4 strongly correlated with the basal-like markers EGFR, P53, and P-cadherin, and negatively correlated with the luminal-like markers ER, PR and GATA3. All but one ER/PR-negative tumors expressed Nectin-4. The detection of Nectin-4 in serum improves the follow-up of patients with MBC: the association CEA/CA15.3/Nectin-4 allowed to monitor 74% of these patients compared to 67% with the association CEA/CA15.3. Serum Nectin-4 is a marker of disease progression, and levels correlate with the number of metastases (P = 0.038). Serum Nectin-4 is also a marker of therapeutic efficiency and correlates, in 90% of cases, with clinical evolution. Conclusion: Nectin-4 is a new tumor-associated antigen for breast carcinoma. Nectin-4 is a new bio-marker whose use could help refine breast cancer taxonomy and improve patients' follow-up. Nectin-4 emerges as a potential target for breast cancer immunotherapy
Nectin-4 is a new histological and serological tumor associated marker for breast cancer
Genome evolution in yeasts.
Identifying the mechanisms of eukaryotic genome evolution by comparative genomics is often complicated by the multiplicity of events that have taken place throughout the history of individual lineages, leaving only distorted and superimposed traces in the genome of each living organism. The hemiascomycete yeasts, with their compact genomes, similar lifestyle and distinct sexual and physiological properties, provide a unique opportunity to explore such mechanisms. We present here the complete, assembled genome sequences of four yeast species, selected to represent a broad evolutionary range within a single eukaryotic phylum, that after analysis proved to be molecularly as diverse as the entire phylum of chordates. A total of approximately 24,200 novel genes were identified, the translation products of which were classified together with Saccharomyces cerevisiae proteins into about 4,700 families, forming the basis for interspecific comparisons. Analysis of chromosome maps and genome redundancies reveal that the different yeast lineages have evolved through a marked interplay between several distinct molecular mechanisms, including tandem gene repeat formation, segmental duplication, a massive genome duplication and extensive gene loss