Chemical composition and biological activities of essential oils of Salvia officinalis aerial parts as affected by diurnal variations

The main objective of this work is to evaluate the impact of the diurnal variation on the essential oil (EO) of Salvia officinalis and on their antioxidant, antifungal and insecticidal potentials. Obtained results showed that the chemical composition of EOs of sage varied significantly during the day. For the EO, the 7 am extract was characterized by the most significant antiradical activity. The EOs of 12 and 5 pm used at a dose of 10 μL were found to have the most effective potential to inhibit the growth of Botrytis cinerea whereas, the EO of 5 pm used at the same dose (10 μL) was the most effective against Fusarium sambucinum. For the fumigant test, the EO from 7 am had the highest activity against Spodoptera littoralis. The EO of 12 pm had the largest repellency activity against Trogoderma granarium. In addition, the EO from 7 am belongs to the repulsive class III, those of 12 and 5 pm belong to the repulsive class IV. The results of this study indicate how to optimize the best harvesting hour to obtain extracts characterized by the best yield of active compounds and by the more effective biological activity.     

Dipeptidyl peptidase III as a DNA marker to investigate epidemiology and taxonomy of Old World Leishmania species

BackgroundDipeptidyl peptidase III (DPPIII) member of M49 peptidase family is a zinc-dependent metallopeptidase that cleaves dipeptides sequentially from the N-terminus of its substrates. In Leishmania, DPPIII, was reported with other peptidases to play a significant role in parasites’ growth and survival. In a previous study, we used a coding sequence annotated as DPPIII to develop and evaluate a PCR assay that is specific to dermotropic Old World (OW) Leishmania species. Thus, our objective was to further assess use of this gene for Leishmania species identification and for phylogeny, and thus for diagnostic and molecular epidemiology studies of Old World Leishmania species.MethodologyOrthologous DDPIII genes were searched in all Leishmania genomes and aligned to design PCR primers and identify relevant restriction enzymes. A PCR assays was developed and seventy-two Leishmania fragment sequences were analyzed using MEGA X genetics software to infer evolution and phylogenetic relationships of studied species and strains. A PCR-RFLP scheme was also designed and tested on 58 OW Leishmania strains belonging to 8 Leishmania species and evaluated on 75 human clinical skin samples.FindingsSequence analysis showed 478 variable sites (302 being parsimony informative). Test of natural selection (dN-dS) (-0.164, SE = 0.013) inferred a negative selection, characteristic of essential genes, corroborating the DPPIII importance for parasite survival. Inter- and intra-specific genetic diversity was used to develop universal amplification of a 662bp fragment. Sequence analyses and phylogenies confirmed occurrence of 6 clusters congruent to L. major, L. tropica, L. aethiopica, L. arabica, L. turanica, L. tarentolae species, and one to the L. infantum and L. donovani species complex.A PCR-RFLP algorithm for Leishmania species identification was designed using double digestions with HaeIII and KpnI and with SacI and PvuII endonucleases. Overall, this PCR-RFLP yielded distinct profiles for each of the species L. major, L. tropica, L. aethiopica, L. arabica and L. turanica and the L. (Sauroleishmania) L. tarentolae. The species L. donovani, and L. infantum shared the same profile except for strains of Indian origin. When tested on clinical samples, the DPPIII PCR showed sensitivities of 82.22% when compared to direct examination and was able to identify 84.78% of the positive samples.ConclusionThe study demonstrates that DPPIII gene is suitable to detect and identify Leishmania species and to complement other molecular methods for leishmaniases diagnosis and epidemiology. Thus, it can contribute to evidence-based disease control and surveillance.     

Electrical activity as a developmental regulator in the formation of spinal cord circuits

Spinal cord development is a complex process involving generation of the appropriate number of cells, acquisition of distinctive phenotypes and establishment of functional connections that enable execution of critical functions such as sensation and locomotion. Here we review the basic cellular events occurring during spinal cord development, highlighting studies that demonstrate the roles of electrical activity in this process. We conclude that the participation of different forms of electrical activity is evident from the beginning of spinal cord development and intermingles with other developmental cues and programs to implement dynamic and integrated control of spinal cord function.     

Effect of medium composition on L-Lysine production by a variant strain ofCorynebacterium clutamicum ATCC 21513

Summary The strainCorunebacterium glutamicum ATCC 21513 grown in a medium containing 17.5% glucose, 5.5% ammonium sulphate and 2% yeast extract was found to produce (under laboratory conditions) high amounts of L-Lysine in this optimized medium. Lysine production, residual sugar and dry cell mass were measured as a function of fermentation time. It was observed that l g of cell mass produced 2.96 g of Lysine. The conversion efficiency was found to be 44%.     

Characterization of Coxsackievirus B4 virus-like particles VLP produced by the recombinant baculovirus-insect cell system expressing the major capsid protein

Molecular Biology Reports - Coxsackievirus B4 (CV-B4) is suspected to be an environmental factor that has the intrinsic capacity to damage the pancreatic beta cells and therefore causes insulitis...     

Relationship between GSTM1 and GSTT1 polymorphisms and schizophrenia: A case–control study in a Tunisian population

There is substantial evidence found in the literature that supports the fact that the presence of oxidative stress may play an important role in the pathophysiology of schizophrenia. The glutathione S-transferases (GSTs) forms one of the major detoxifying groups of enzymes responsible for eliminating products of oxidative stress. Interindividual differences observed in the metabolism of xenobiotics have been attributed to the genetic polymorphism of genes coding for enzymes involved in detoxification. Thus, in this study we investigated the association of glutathione S-transferase Mu-1 (GSTM1) and glutathione S-transferase theta-1 (GSTT1) gene deletion polymorphisms and schizophrenia in a Tunisian population. A case–control study including 138 schizophrenic patients and 123 healthy controls was enrolled. The GSTM1 and GSTT1 polymorphisms were analyzed by multiplex polymerase chain reaction (PCR). No association was found between the GSTM1 genotype and schizophrenia, whereas the prevalence of the GSTT1 active genotype was significantly higher in the schizophrenic patients (57.2%) than in the controls (45.5%) with (OR = 0.6, IC 0.37–0.99, p = 0.039). Thus, we noted a significant association between schizophrenia and GSTT1 active genotype. Furthermore, the combination of the GSTM1 and GSTT1 null genotypes showed a non-significant trend to an increased risk of schizophrenia. The present finding indicated that GSTT1 seems to be a candidate gene for susceptibility to schizophrenia in at least Tunisian population.     

Association between clinical expression and molecular heterogeneity in β-thalassemia Tunisian patients

Beta-thalassemia is the most frequent hereditary blood disorder in Tunisia because of its geographic localization and history. This pathology is characterized by a complex multisystem process with genetic and biochemical interactions. The aim of this work was to establish phenotype/genotype association through studying the distribution and the relationship between β-thalassemia and α-thalassemia mutations and three polymorphic markers: the C → T polymorphism at ?158 of the Gγ gene, the RFLP haplotype and the repeated sequence (AT)_xT_y in the β globin silencer, in two groups of β-thalassemia major and β-thalassemia intermedia (TI) patients. Statistical analysis has shown that moderate expression seen in TI patients was significantly associated to β⁺ ?87 (C → G), ?30 (T → A) and IVSI-6 (T → C) mutations, haplotypes VIII, IX and Nb and to XmnI polymorphism. The regression analysis of combined genotypes (mutation/XmnI/RFLP haplotype) revealed that they contribute to justify 17.1 % of clinical expression diversity (p < 0.05). Among the studied genotypes the XmnI polymorphism seems to be the most determinant modulating factor, followed by the β-thalassemia mutation and RFLP haplotype. Our findings highlight the heterogeneity of molecular background of β-thalassemia that would be responsible of clinical variability.