Bayesian phylogenetic analysis of the influenza-A virus genomes isolated in Tunisia, and determination of potential recombination events.

The influenza-A virus (IAV) causes seasonal epidemics and presents a pandemic risk with the possibility of genetic re-assortment, allowing the emergence of new strains. The evolution of IAVes is done most often by relatively frequent re-assortment between gene segments, but the hypothesis of their evolution by recombination between RNA segments has not been justified to this date. Here, we examine this hypothesis by Bayesian phylogenetic analysis, to test if recombination events have occurred between genomic RNA segments.

Investigation of Extracts from Tunisian Ethnomedicinal Plants as Antioxidants, Cytotoxins, and Antimicrobials.

Objective: To determine the medicinal potential of various plants and their parts extracted with different solvents.

Methods: The total phenolic content of acetonitrile/water (60%-40%) (ACN/W) and aqueous (W) extract fractions was determined by high-performance liquid chromatography (HPLC), and terpenic compounds were detected by gas chromatography/mass spectrometry (GC/MS). Antioxidant activity of the samples was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and β-carotene bleaching method.

Assessing the effect of zooprophylaxis on zoonotic cutaneous leishmaniasis transmission: a system dynamics approach.

Capturing or diverting the disease carrying vector from humans can reduce the transmission of vector borne diseases such as leishmaniasis. The use of animals that act as dead-end hosts to relieve the vector (sandfly) bites on humans is called zooprophylaxis. However, as the number of blood meal providers especially domestic animals increases, the sandflies enhanced availability of blood meals will improve its number and survival, thereby countering the impact of diverting bites from humans.

Lack of protection of pre-immunization with saliva of long-term colonized Phlebotomus papatasi against experimental challenge with Leishmania major and saliva of wild-caught P. papatasi.

Immunity to saliva of Phlebotomus papatasi protects against Leishmania major infection as determined by co-inoculation of parasites with salivary gland homogenates (SGHs) of this vector. These results were obtained with long-term colonized female P. papatasi.

DNA based vaccination with a cocktail of plasmids encoding immunodominant Leishmania (Leishmania) major antigens confers full protection in BALB/c mice.

Despite the lack of effective vaccines against parasitic diseases, the prospects of developing a vaccine against leishmaniasis are still high. With this objective, we have tested four DNA based candidate vaccines encoding to immunodominant leishmania antigens (LACKp24, TSA, LmSTI1 and CPa). These candidates have been previously reported as capable of eliciting at least partial protections in the BALB/c mice model of experimental cutaneous leishmaniasis.

Zooprophylaxis: impact of breeding rabbits around houses on reducing the indoor abundance of Phlebotomus papatasi.

Zooprophylaxis is the use of animals to deviate vectors from humans. The indoor abundance of Phlebotomus papatasi in houses with rabbit holes in the peridomestic areas are significantly lower than the indoor abundance in houses without rabbit holes in their peridomestic areas. Introduction of rabbits in artificial underground holes in peridomestic areas reduced significantly the indoor abundance of P.

Field trials of a very potent rabies DNA vaccine which induced long lasting virus neutralizing antibodies and protection in dogs in experimental conditions.

Kinetics of antibody responses and protection against rabies were investigated after injection of a single dose of rabies DNA vaccine and compared to those induced by one or two injections of cell culture-derived vaccine in dogs issued from the common local breed and reared in experimental conditions. Rabies DNA vaccine administered intradermally by a jet injector in the inner face of the ear was by far more efficient in inducing long lasting high titers of virus neutralizing antibodies compared to cell culture vaccine Rabisin administered either subcutaneously or intramuscularly. Four years after vaccine administration of either DNA or cell culture-derived rabies vaccines, full protection against a rabies peripheral challenge was achieved.

A comparative evaluation of different DNA vaccine candidates against experimental murine leishmaniasis due to L. major.

Over the past few years, several reports of DNA vaccines against murine cutaneous experimental leishmaniasis came out with promising but sometimes discordant results. The present studies were designed to compare, under similar conditions, the protective effects in the highly susceptible BALB/c mice of DNA vaccine candidates encoding to various Leishmania major antigens. The candidate DNA vaccines encode to the following antigens: LACK, PSA2, Gp63, LeIF and two newly identified p20 and Ribosomal like protein, in addition to different truncated portions of the LACK antigen.

Post-exposure therapy in mice against experimental rabies: a single injection of DNA vaccine is as effective as five injections of cell culture-derived vaccine.

Two rabies post-exposure therapies were comparatively evaluated: BALB/c mice were challenged at day 0 with rabies virus and then received either a single dose of rabies DNA vaccine administered at day 0, or five doses of cell culture-derived rabies vaccine administered at days 0, 3, 7, 15 and 28. Both regimens, rapidly triggered protective levels of neutralizing antibodies against rabies virus in vaccinated mice. In addition, one injection of DNA vaccine protected 53% of the challenged mice, compared to 40% of mice protected after five injections of cell culture-derived vaccine.