L’apport de l’imagerie hybride TEMP/TDM dans la prise en charge du cancer différencié de la thyroïde

IntroductionSingle photon emission computed tomography combined with a low dose computed tomography (SPECT/CT), is a hybrid imaging integrating functional and anatomical data. The purpose of our study was to evaluate the contribution of the SPECT/CT over traditional planar imaging of patients with differentiated thyroid carcinoma (DTC).MethodsPost-therapy iodine 131 (¹³¹I) whole-body scan followed by cervico-thoracic SPECT/CT, were performed in 100 patients with DTC.ResultsAmong these 100 patients followed for a predominantly papillary DTC, planar imaging and SPECT/CT, were perfectly concordant in 70% of patients and discordant in the remaining 30%. The use of fusion imaging SPECT/CT compared to conventional planar imaging allowed us to correct our therapeutic approach in 27% (27/100 patients), according to the protocols of therapeutic management of our institute.ConclusionSPECT/CT is a hybrid imaging modality which provides better identification and more correct anatomic localization of the foci of radioiodine uptake with impact on therapeutic management.     

Demographic,seed and microsite limitations to seedling recruitment in semi-arid mine site restoration

Plant and Soil - Understanding limitations to plant recruitment is a key element in devising effective restoration of semi-arid ecosystems: only when these limitations are identified can management...     

Description and mapping of the resistance of DBA/2 mice to TNF-induced lethal shock

In our search for genes that inhibit the inflammatory effects of TNF without diminishing its antitumor capacities we found that, compared with C57BL/6 mice, DBA/2 mice exhibit a dominant resistance to TNF-induced lethality. Tumor-bearing (C57BL/6 x DBA/2)(BXD)F(1) mice completely survived an otherwise lethal TNF/IFN-gamma-antitumor therapy with complete regression of the tumor. This was not the case for C57BL/6 mice. Genetic linkage analysis revealed that TNF resistance is linked to a major locus on distal chromosome 6 and a minor locus on chromosome 17. Compared with littermate controls, chromosome substitution mice carrying a DBA/2 chromosome 6 in a C57BL/6 background were significantly protected against TNF and TNF/IFN-gamma, albeit less so than DBA/2 mice. Definition of a critical region of 13 Mb on chromosome 6 was the highest mapping resolution obtained. Further analysis of candidate genes may provide a powerful tool to control TNF-induced pathologies in humans.     

Reproductive biology of the annular seabream,Diplodus annularis (Linnaeus, 1758), in the Gulf of Gabes (Central Mediterranean)

Annular seabream, Diplodus annularis (Linnaeus, 1758), were caught off the coast of the Gulf of Gabes (Southern Tunisia, Central Mediterranean) between April 2008 and March 2010 by commercial catches. With a total 2066 specimens the fish ranged in size from 7.7 cm to 18.5 cm total length and from 7.5 g to 123.3 g in weight. Changes in biological parameters (weight, length, gonadosomatic index, hepatosomatic index and condition factor) were examined in order to provide information on the spawning period and reproductive cycle in the gulf. Overall sex ratio was 1 : 1.52 in favour of females. The reproductive season extends from March to June, with a spawning activity peak in May. Total length at sexual maturity was 10.5 ± 0.22 cm (males) and 10.6 ± 0.3 cm (females). The results of this study could help to establish a recommended minimum capture size.     

Influence of lipids on membrane assembly and stability of the potassium channel KcsA

A novel antibacterial peptide, moricin, isolated from the silkworm Bombyx mori, consists of 42 amino acids. It is highly basic and the amino acid sequence has no significant similarity to those of other antibacterial peptides. The 20 structures of moricin in methanol have been determined from two-dimensional 1H-nuclear magnetic resonance spectroscopic data. The solution structure reveals an unique structure comprising of a long alpha-helix containing eight turns along nearly the full length of the peptide except for four N-terminal residues and six C-terminal residues. The electrostatic surface map shows that the N-terminal segment of the alpha-helix, residues 5-22, is an amphipathic alpha-helix with a clear separation of hydrophobic and hydrophilic faces, and that the C-terminal segment of the alpha-helix, residues 23-36, is a hydrophobic alpha-helix except for the negatively charged surface at the position of Asp30. The results suggest that the amphipathic N-terminal segment of the alpha-helix is mainly responsible for the increase in permeability of the membrane to kill the bacteria.     

Morphological analysis of three equivocal sibling species of Deprea (Solanaceae)

Taxonomic confusion among closely related and morphologically similar Deprea species has persisted in the literature and in the identification of species. Morphological variation among three closely related, monophyletic Deprea species was studied to determine if and how they can be distinguished. Their sympatric occurrence in Venezuela afforded an opportunity to couple field study with analysis of herbarium specimens representing their entire geographic range. An analysis of 94 morphological characters resulted in five vegetative and 13 reproductive taxonomically informative traits. Canonical variates analysis clearly separated the three species using six quantitative traits. We conclude that these taxa, although quite variable and similar morphologically, are taxonomically distinct. Results of character analysis indicated that D. orinocensis is morphologically more similar to D. bitteriana than either are to D. paneroi. In D. paneroi, small, sterile anthers on fruit-bearing plants and the absence of fruits on plants possessing large, plllen-bearing anthers, suggest cryptic dioecy. Based on these data, D. granulosa is considered to be a synonym of D. orinocensis: Athenaea bitteriana, a misapplied synonym, is the correct basionym and is applicable to many specimens identified as D. granulosa. We submit a new combination, D. bitteriana (Werderm.) Sawyer & Benítez, and designate a lectotype to accommodate these findings.     

Involvement of the endoplasmic reticulum in peroxisome formation

The traditional view holds that peroxisomes are autonomous organelles multiplying by growth and division. More recently, new observations have challenged this concept. Herein, we present evidence supporting the involvement of the endoplasmic reticulum (ER) in peroxisome formation by electron microscopy, immunocytochemistry and three-dimensional image reconstruction of peroxisomes and associated compartments in mouse dendritic cells. We found the peroxisomal membrane protein Pex13p and the ATP-binding cassette transporter protein PMP70 present in specialized subdomains of the ER that were continuous with a peroxisomal reticulum from which mature peroxisomes arose. The matrix proteins catalase and thiolase were only detectable in the reticula and peroxisomes. Our results suggest the existence of a maturation pathway from the ER to peroxisomes and implicate the ER as a major source from which the peroxisomal membrane is derived.     

Associations of rs1883832 and rs4810485 polymorphisms of CD40 gene with myocardial infarction in the Tunisian population

Context: Cluster of differentiation 40 (CD40), and its ligand CD40L, are major co-stimulatory molecules whose interactions are important in both cellular and humoral immunity, and has been suggested to play a role in the pathogenesis of acute coronary syndrome.

Objective: The aim of this study was to examine the association of CD40 polymorphisms (-1?C>T (rs1883832) and 945G>T (rs4810485)) and myocardial infarction (MI), and to test the association of CD40 gene haplotypes with MI in Tunisians.

Materials and methods: Three hundred and fifty MI patients and 301 apparently healthy controls were included in the study. The polymorphisms of CD40 were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

Results: There were significant differences in the genotype and allele frequencies of CD40 gene -1?C>T (rs1883832) polymorphism between cases and controls. Stratifying according to gender, the association between the TT genotype and MI was statistically significant in males, only. Haplotype analysis revealed that the C-T and T-G haplotypes were associated with an increased risk of MI (p?=?0.012 and p?<?0.001, respectively).

Conclusions: Our work showed a significant association between the -1?C>T (rs1883832) polymorphism of the CD40 gene and MI in the Tunisians.     

Autophagy and senescence: A new insight in selected human diseases

Senescence and autophagy play important roles in homeostasis. Cellular senescence and autophagy commonly cause several degenerative processes, including oxidative stress, DNA damage, telomere shortening, and oncogenic stress; hence, both events are known to be interrelated. Autophagy is well known for its disruptive effect on human diseases, and it is currently proposed to have a direct effect on triggering senescence and quiescence. However, it is yet to be proven whether autophagy has a positive or negative impact on senescence. It is known that elevated levels of autophagy induce cell death, whereas inadequate autophagy can trigger cellular senescence. Both have important roles in human diseases such as aging, renal degeneration, neurodegenerative disorders, and cancer. Therefore, this review aims to highlight the relevance of senescence and autophagy in selected human ailments through a summary of recent findings on the connection and effects of autophagy and senescence in these diseases.