In vitro antiviral activities of extracts derived from Daucus maritimus seeds

The antiviral activities of extracts from Daucus maritimus seeds were investigated against the reverse transcriptase of human immunodeficiency virus (HIV) type 1 and a panel of RNA-dependent RNA polymerases of dengue virus, West Nile virus (WNV) and hepatitis C virus (HCV). The extracts showed moderate to potent inhibition rates against the four viral polymerases. The ethyl acetate extract exhibited a potent inhibitory effect against WNV's RdRp, with an IC₅₀ value of 8 µg mL⁻¹. The F₂ fraction exhibited potent inhibitory activity against WNV and HCV's RdRps, with IC₅₀ values 1 and 5 µg mL⁻¹, respectively. The P₂ fraction also showed potent inhibitory effects on WNV and HCV's RdRps, with IC₅₀ values 2.7 and 4 µg mL⁻¹, respectively. The results suggest that these extracts are candidates for the development of new anti-WNV RpDp and anti-HCV RpDp agents.

Anti-inflammatory and analgesic activities of Tunisian Citrullus colocynthis Schrad. immature fruit and seed organic extracts

BACKGROUND AND OBJECTIVES

Inflammations and immune-related diseases including rheumatoid arthritis are widespread in the entire globe. The treatment of these illnesses is mainly based on the use of synthetic and biotechnological drugs, in recent years. Tunisian traditional medicine is a potential source of new remedies namely Citrullus colocynthis Schrad. (Cucurbitaceae): endemic in southern Tunisia and used in folk medicine to treat many inflammation disorders. Our goal was to assess the in vivo analgesic and anti-inflammatory activities of Tunisian Citrullus colocynthis immature fruit and seed organic extracts (petroleum ether, chloroform, ethyl acetate, acetone and finely methanol extract).

MATERIAL AND METHODS

Yields of prepared organic extracts are gravimetrically determined. For the analgesic and anti-inflammatory activities, we have used respectively, the acetic acid writhing test in mice and the carrageenan-induced paw edema assay in rats.

RESULTS AND DISCUSSION

All extracts displayed an important analgesic and anti-inflammatory activities at different doses without inducing any side effects. This study has demonstrated the analgesic and anti-inflammatory activities of Citrullus colocynthis immature fruit and seed extracts. Experiment results provide scientific insight into the ancient practice of utilizing Citrullus colocynthis Schrad. as analgesic and as anti-inflammatory agents.

Detection and molecular characterization of enteric viruses in environmental samples in Monastir, Tunisia between January 2003 and April 2007

AIMS

A prospective study was performed to characterize the main human enteric viruses able to persist in sewage samples and in shellfish tissues, and to establish the correlation between environmental strains and viral infantile diarrhoea observed in the same area during the same period.

METHODS AND RESULTS

A total of 250 sewage (raw and treated) and 60 shellfish samples were collected between January 2003 and April 2007 in Monastir region, Tunisia. Group A rotavirus (RVA) was detected in 80 (32%) sewage samples, norovirus (NoV) in 11 (4·4%) and enteric adenovirus (AdV) in 1 (0·4%). Among 60 shellfish samples collected near sewage effluents, one was contaminated by NoV (1·6%).

CONCLUSION

Our data represent the first documentation in Tunisia, combining gastroenteritis viruses circulating in the environment and in clinical isolates. We observed a correlation between environmental strains and those found in children suffering from gastroenteritis during the same period study. This suggests the existence of a relationship between water contamination and paediatric diarrhoea.

SIGNIFICANCE AND IMPACT OF THE STUDY

Our results address the potential health risks associated with transmission of human enteric viruses through water-related environmental routes. The research findings will aid in elucidating the molecular epidemiology and circulation of enteric viruses in Tunisia and in Africa, where data are rare.

[Ocular complications of HIV infection: experience of the Northern Excellence Pole of Morocco]

INTRODUCTION

HIV infection is associated with a wide variety of ophthalmic manifestations. The objective of this study was to identify the ocular complications of HIV/AIDS in Morocco.

MATERIAL AND METHODS

A retrospective study conducted in the internal medicine department of the Rabat Teaching Hospital between 1998 and 2008. All HIV-positive patients were retained for the study. Each patient had an exhaustive ocular examination.

RESULTS

Of 115 ophthalmologic examinations, 28 were abnormal. Twenty-seven patients had stage C HIV infection and one patient was in stage A. The ocular manifestations were: 21 cases of ocular HIV-related anomalies (microangiopathies), four cases of cytomegalovirus (CMV) retinitis, one case of toxoplasmosis chorioretinitis, one case of CMV retinitis associated with toxoplasmosis chorioretinitis, two cases of Cryptococcus neoformans infection, two cases of varicella-zoster virus (VZV) retinitis, and one case of conjunctival Kaposi sarcoma. The CD4 count average was of 86±91/mm(3). Twenty-six patients had a CD4 count lower than 200/mm(3). Progression was favorable in 85 % of the cases, with three cases of blindness: bilateral in a case of VZV retinitis and unilateral in two cases of CMV retinitis and toxoplasmosis chorioretinitis.

CONCLUSION

CMV infection is the main ocular opportunistic infection in our series. However, Highly Active Antiretroviral Treatment (HAART) may be the cause for the decline in the prevalence of ocular diseases and visual impairment in HIV/AIDS.

Surface plasmon resonance immunosensor for bacteria detection

This work describes an approach for the development of two bacteria biosensors based on surface plasmon resonance (SPR) technique. The first biosensor was based on functionalized gold substrate and the second one on immobilized gold nanoparticles. For the first biosensor, the gold substrate was functionalized with acid-thiol using the self-assembled monolayer technique, while the second one was functionalized with gold nanoparticles immobilized on modified gold substrate. A polyclonal anti-Escherichia coli antibody was immobilized for specific (E. coli) and non-specific (Lactobacillus) bacteria detection. Detection limit with a good reproducibility of 10(4) and 10(3) cfu mL(-1) of E. coli bacteria has been obtained for the first biosensor and for the second one respectively. A refractive index variation below 5x10(-3) due to bacteria adsorption is able to be detected. The refractive index of the multilayer structure and of the E. coli bacteria layer was estimated with a modeling software.

Coxsackievirus B4 and type 1 diabetes pathogenesis: contribution of animal models

The role of enteroviruses, in particular type B coxsackieviruses (CV-B), in type 1 diabetes (T1D) pathogenesis is supported by epidemiological, clinical and experimental observations.The investigation of T1D pathogenesis benefits from the contribution of animal models called spontaneously diabetic. Among these animals the non-obese diabetic (NOD) mouse and the bio-breeding diabetes-prone (BBDP) rat present a genetic susceptibility manifested by the expression of an autoimmune diabetes similar to the pathology observed in human beings. Other models whose genetic predisposition is less known are of considerable contribution as well. Numerous major observations relative to several aspects of T1D pathogenesis in the context of CV-B infections, such as susceptibility, diabetogenicity, pancreatotropism, mechanisms of beta cells destruction and others, have been deduced thanks to investigations with animal models. Despite their limits, these models are necessary in improving our knowledge of the role of enteroviruses, like CV-B4, in the pathogenesis of T1D, and the recent advances ensuing from their contribution may have important therapeutic and preventive spin-offs.