[Ballistic trauma of the face: A new scourge in Tunisia]. / Traumatisme balistique de la face : un nouveau fléau en Tunisie.

INTRODUCTION: Ballistic trauma of the face has aroused growing interest since the proliferation of conflicts in the world and particularly in the fight against terrorism. Their polymorphous and disfiguring character, their particular evolution and prognosis due to the ballistic aetiology, differentiate them from classic maxillofacial trauma. Tunisia did not escape this scourge after the revolution of 2011, and must therefore face the challenge of ballistic trauma in general and of the face in particular. MATERIALS AND METHODS: We conducted a descriptive retrospective study on 30 patients who were victims of ballistic trauma of the face in the otolaryngology and maxillofacial surgery and ophthalmology departments of the Main Military Hospital of Tunis during the period from January 2011 to April 2018. Our objective was to assess the prevalence of these traumas in Tunisia after the revolution, and to assess their clinical and therapeutic aspects. RESULTS: Our results showed a clear upward trend in these traumas, mainly caused by the opposition of our armed forces to the terrorist threat. The discussion of our results was therefore descriptive, comparing them to the literature. CONCLUSION: Currently, it is imperative to develop a strategy for precise and effective management of ballistic trauma of the face due to the increase of armed conflicts, attacks and terrorist acts. Likewise, technological advances to develop soldier protection systems must be implemented.

A DFT study of Janus structure of S and Se in HfSSe layered as a promising candidate for electronic devices.

The transition-metal dichalcogenides are presently being intensively researched because of their unique optoelectronic properties. Further, the success of TMDs in all areas of science without exception has opened the street to find other two-dimensional materials. Based on density functional theory, we study the vibrational and electronic properties of the mixed-phase of S and Se in HfSSe system, i.e, HfSSe monolayer and HfSSe/HfSSe bilayer. In this framework, our systems are full dynamically stable, which shown by their phonon dispersion. Also, we found that the HfSSe (heterolayer) monolayer is an indirect semiconductor (0.63 eV with BLYP), while the HfSSe (alternating) monolayer is a direct semiconductor (0.753 eV with BLYP). Our AA, AB, AA', and AB' of HfSSe/HfSSe (heterolayer) bilayer are indirect band gaps in a range 0.361-0.830 eV, which are promising candidates for electronic devices as field-effect transistors, photodetectors, and other optoelectronics. Nevertheless, HfSSe/HfSSe (alternating) bilayer is a direct bandgap semiconductor with a value of 0.671 eV, when vdW is used.

DFT study of electronic and optical properties of silicene functionalized with chemical groups.

In the last years, a band-gap tunability is particularly interesting for the fabrication of flexible and ultrathin optical devices since it is known from earlier studies that two-dimensional materials can display a much larger sunlight absorption than commonly employed semiconductors. Using density functional theory, we study the structural, electronic and optical properties such as dielectric function, absorption coefficient, conductivity, and a refractive index of silicene monolayer functionalized with chemical groups or atoms (i.e, X-Si-Y, Cl-Si-Br, and X'-Si-X' with X = Cl, F, or OH; Y = CN; X'  = CN, CH, or NH). In this framework, by means of AIMD calculations, we show that they are dynamically stable, while their electronic band-gap, as obtained with the GGA approximation, ranges between 1.25 and 2.13 eV, except for CH-Si-CH and NH-Si-NH, which are found to be metallic. Additionally, we show that an external electric field can modify significantly the electronic structure of some of these systems.

A first principle study of graphene functionalized with hydroxyl, nitrile, or methyl groups.

By means of ab initio calculations, we study the functionalization of graphene by different chemical groups such as hydroxyl, nitrile, or methyl. Two extreme cases of functionalization are considered: a single group on a supercell of graphene and a sheet of graphene fully functionalized. Once the equilibrium geometry is obtained by density functional theory, we found that the systems are metallic when a single group is attached to the sheet of graphene. With the exception of the nitrile functionalized boat configuration, a large bandgap is obtained at full coverage. Specifically, by using the GW approximation, our calculated bandgaps are direct and range between 5.0 and 5.5 eV for different configurations of hydroxyl functionalized graphene. An indirect GW bandgap of 6.50 eV was found in nitrile functionalized graphene while the methyl group functionalization leads to a direct bandgap with a value of 4.50 eV. Since in the two limiting cases of minimal and full coverage, the electronic structure changes drastically from a metal to a wide bandgap semiconductor, a series of intermediate states might be expected by tuning the amount of functionalization with these different groups.

DEAD-box proteins, like Leishmania eIF4A, modulate interleukin (IL)-12, IL-10 and tumour necrosis factor-alpha production by human monocytes.

Previously we showed that His-tagged, recombinant, Leishmania infantum eukaryotic initiation factor (LeIF) was both an RNA-dependent ATPase and an ATP-dependent RNA helicase in vitro, as described for other members of the DEAD-box helicase family. In addition, we showed that LeIF induces the production of IL-12, IL-10, and TNF-α by human monocytes. This study aims to characterize the cytokine-inducing activity in human monocytes of several proteins belonging to the DEAD-box family from mammals and yeast. All tested proteins contained the 11 conserved motifs (Q, I, Ia, GG Ib, II, III, IV, QxxR, V and VI) characteristic of DEAD-box proteins, but they have different biological functions and different percentages of identities with LeIF. We show that these mammalian or yeast recombinant proteins also are able to induce IL-12, IL-10 and TNF-α secretion by monocytes of healthy human subjects. This cytokine-inducing activity is proteinase K sensitive and polymyxin B resistant. Our results show that the induction of cytokines in human monocytes is not unique to the protein LeIF of Leishmania, and it suggests that the activity of certain DEAD-box proteins can be exploited as adjuvant and/or to direct immune responses towards a Th1 profile in vaccination or immunotherapy protocols.

Leishmania infantum LeIF and its recombinant polypeptides modulate interleukin IL-12p70, IL-10 and tumour necrosis factor-α production by human monocytes.

Leishmania eukaryotic initiation factor (LeIF) antigen, a Leishmania protein, was shown to induce IL-12, IL-10 and tumour necrosis factor-α (TNF-α) production by human monocytes-derived macrophages and dendritic cells from healthy individuals. This cytokine-inducing activity was previously found to be located in the amino-terminal region of LeIF protein. This study aimed at characterizing the cytokine-inducing activity of Leishmania infantum LeIF [Leishmania (L.) infantum (LieIF)] and at defining the fragments necessary for inducing cytokine secretion. Eleven rationally designed recombinant polypeptides, corresponding to the entire LeIF protein or parts of it, were expressed and used to stimulate monocytes from healthy individuals. Leishmania (L.) infantum was able to induce IL-12p70, IL-10 and TNF-α secretion in human monocytes. In addition, both amino- (1-226) and carboxyl-terminal (196-403) parts of the protein were shown to induce significant levels of the three cytokines analysed. However, IL-12p70-inducing activity was not significant when monocytes were stimulated with the fragments 129-226 and 129-261, inferring that IL-12p70-inducing activity was primarily located within amino acids 1-129 and 261-403. Although the full-length LieIF protein was a more potent inducer than the tested fragments, a significant cytokine-inducing activity was maintained in smaller amino acid regions. This work suggests that cytokine-inducing activity of LieIF or its parts could be exploited in vaccination or immunotherapy protocols.

[Locally advanced unresectable pancreatic cancer: Induction chemoradiotherapy followed by maintenance gemcitabine versus gemcitabine alone: Definitive results of the 2000-2001 FFCD/SFRO phase III trial]. / Cancer du pancréas localement évolué non resécable : chimioradiothérapie d'induction suivie de chimiothérapie par gemcitabine contre chimiothérapie exclusive par gemcitabine : résultats définitifs de l'étude de phase III 2000-2001de la FFCD et de la SFRO.

PURPOSE: To compare chemoradiation with systemic chemotherapy to chemotherapy alone in locally advanced pancreatic cancer. PATIENTS AND METHODS: One hundred and nineteen patients with locally advanced pancreatic cancer, with World Health Organization performance status of zero to two were randomly assigned to either the induction chemoradiation group (60 Gy, 2 Gy/fraction; concomitant 5-fluoro-uracil infusion, 300 mg/m(2) per day, days 1-5 for 6 weeks; cisplatin, 20 mg/m(2) per day, days 1-5 during weeks 1 and 5) or the induction gemcitabine group (GEM: 1000 mg/m(2) weekly for 7 weeks). Maintenance gemcitabine (1000 mg/m(2) weekly, 3/4 weeks) was given in both arms until disease progression or toxicity. RESULTS: Overall survival was shorter in the chemoradiation than in the gemcitabine arm (median survival 8.6 [99% confidence interval 7.1-11.4] and 13 months [8,9,9-18], p=0.03). One-year survival was, respectively, 32 and 53%. These results were confirmed in a per-protocol analysis for patients who received 75% or more of the planned dose of radiotherapy. More overall grades 3-4 toxic effects were recorded in the chemoradiation arm, both during induction (36 versus 22%) and maintenance (32 versus 18%). CONCLUSION: This intensive induction schedule of chemoradiation was more toxic and less effective than gemcitabine alone.

[A variant of DDRT-PCR using anchored mini-exon primers for identification of differentially expressed sequences in Leishmania infantum]. / Une variante du dDRT-PCR utilisant des amorces mini-exon ancrées pour l'identification de séquences différentiellement exprimées chez leishmania infantum.

Leishmania infantum (L.i) is responsible for visceral (VL) or cutaneous (CL) leishmaniasis. Previous studies done in Honduras by differential display reverse transcriptase-polymerase chain reaction (DDRT-PCR) failed to demonstrate differences in expression profiles among L. infantum VL and CL parasites. For purpose of comparing expression among L. infantum isolates in Tunisia, a variant of this technique adapted from a commercial kit was developed involving pairs of random and anchored mini-exon primers for isolation and identification of differentially displayed cDNAs. To assess the efficiency of this variant, 34 pairs were applied to 2 consecutive dilutions of cDNAs from promastigotes at end of in vitro exponential growth of 2 visceral (LV50) and cutaneous (DREP14) isolates from Tunisia, thus increasing chance for observing differences among the cDNAs. Profiles were compared and analyzed as regards number and phenotype of bands displayed in 4 types of highly similar amplification profiles among the 2 cDNAs; 26 primer pair combinations generated in total 6.8% differentially displayed bands that had variable intensities or were present/absent, in comparable proportions in the 2 isolates. Analysis further demonstrated differences in amplification efficiency of some primers, emphasizing on qualitative and quantitative impact of relative proximity of the priming sites. Nine present/absent bands were cloned, sequenced and analyzed in silico. Mismatches at priming sites seem to underlie amplification of such bands. Only five products could be referred to annotated gene. Among the genes identified, we list histone H4, largely known to be differentially expressed among L.i stages, and "NTF2-like" for which overexpression in one cDNA was here confirmed. To conclude, the variant developed could be used further in Leishmania expression analysis with appropriate cautions about false positives.

[Differentiation among cutaneous Leishmania species upon amplification of a sequence of dipeptidyl peptidase III encoding gene]. / Différenciation des espèces responsables de leishmaniose cutanée par une amplification PCR du gène codant pour la dipeptidyl peptidase III.

Leishmaniasis are a group of vector-born, parasitic diseases caused by protozoan of the Leishmania genus, that includes visceral or cutaneous forms. Cutaneous leishmaniasis (CL) refers to a group of diseases because of the variability of clinical manifestations, caused by a large number of Leishmania species. In Tunisia, three different forms of CL are encountered, having different causal agents L. infantum, L. major and L. tropica. For the purpose of this study, we assessed the potential of polymorphic sites in dipeptidyl peptidase III (DPP III) encoding gene to differentiate among Leishmania species encountered in Tunisia. A pair of forward and reverse primers amplifying a 664 bp DPP III sequence were designed in regions including 2 mutations in the forward primer and 1 in the reverse, and were used to amplify DNA from diverse species of Leishmania parasites including L. infantum, L. major, L. tropica, L. donovani, L. chagasi, L. arabica, L. aethiopica and L. tarentolae. Amplification was positive for all tested Leishmania species except for L. infantum, L. chagasi, L. archibaldi, L. donovani and L. tarentolae. In case of cutaneous Leishmania species encountered in Tunisia, amplification was positive for both L. tropica and L. major and negative in case of L. infantum. This ability to differentiate L. infantum from L. tropica/L. major constitutes a first step in the taxonomy of cutaneous species prevalent in Tunisia.

Molecular analyses of Old World Leishmania RAPD markers and development of a PCR assay selective for parasites of the L. donovani species Complex.

Three amplicons, appearing in a species-specific manner on the electrophoregrams of RAPD reactions that were obtained with primer OPA1, OPA1-800, OPA1- 900, and OPA1-1200, are analyzed in this study. The study revealed that each of these products is composed of one Leishmania DNA band, taxonomically conserved among the different Old World species studied. Subsequently, only the electrophoretic position of the RAPD products can be considered species-specific. In addition, sequence data, genomic organization, and chromosomal location have proved that these fragments are different and physically independent. However, they possess common features related to the presence of different kinds of short DNA repeats, more particularly microsatellites and a CCCTTC motive, corresponding to the 3' half of the OPA1 primer. These results suggest that the OPA1 primer has initiated amplification from different priming sites, having a species-specific location. This corresponds to sequence micro-heterogeneity of DNA fragments present within the different species and leading eventually to a selective amplification of different RAPD products. This characteristic has been used to develop an original selective PCR test based on the sequence of the OPA1-800 product, in which only DNAs from the L. donovani species complex are amplified. Restriction site polymorphisms and sequence variations are identified within the PCR fragment amplified from these parasite DNAs. In fact, the OPA1-800 fragment proved to be a useful DNA marker either as a DNA probe or as a target for PCR-based assays. This tool can therefore be recommended for the control of Old World Leishmania parasites, such as species discrimination, molecular tracking of isolates, or study of polymorphisms within the L. donovani species complex. Moreover, the molecular bases underlying the amplification of the RAPD fragments studied correspond to mechanisms already described. Although they do not account for the amplification of all Leishmania RAPD products, such mechanisms stress some of the pitfalls of the technique, which need to be taken into consideration. We have identified at least misleading observations of DNA bands amplified in a species-specific manner, in spite of their presence in the genome of the other taxa, and relatedness between bands within the amplification profiles. Therefore, recommendations for careful interpretation of RAPD data in population genetics or phylogenetic analyses are reiterated. Molecular analyses are essential to validate conclusions.