[Specular microscopy findings in active uveitis]. / Résultats de la microscopie spéculaire au cours des uvéites actives.

PURPOSE: To study the effect of ocular inflammation in active uveitis on the corneal endothelium. MATERIALS AND METHODS: This is a prospective cross-sectional study involving 63 eyes of 38 patients with active newly-diagnosed uveitis. Eighty-four eyes of 42 non-uveitic subjects served as a control group. All patients underwent detailed ophthalmic examination, laser flare photometry, and non-contact specular microscopy. Eyes with uveitis had a follow-up visit at one month after initiation of treatment, including laser flare photometry and specular microscopy. RESULTS: The mean age of the active uveitis patients was 33 (range: 9-67 years) with 21 men (55%) and 17 women (45%). For the uveitis patients at baseline, the mean flare value was 32ph/ms (range: 15-100ph/ms) with flare photometry value ≥50ph/ms in 13 eyes (21%) and<50ph/ms in 50 eyes (79%). At baseline, cell density (CD) of the uveitis patients was similar to CD in control eyes (p꞊0.16). The percent of hexagonality was significantly lower (p<0.0001), and the coefficient of variance (CV) (p<0.0001) and central corneal thickness (CCT) (p<0.0001) were significantly higher than in the control group. After one month, there was a significant decrease in flare photometry values (p<0.0001), with a mean flare value of 14.5ph/ms (range: 4-60ph/ms). In the active uveitis group, the overall results of specular microscopy did not significantly vary between the initial examination and the 1-month examination. For eyes with flare photometry value ≥50ph/ms at baseline, CD and hexagonal cell count significantly increased on the 1-month examination (p꞊0.01 and p꞊0.02 respectively), while CV and CCT decreased significantly at the one-month follow-up visit (p꞊0.007/p꞊0.03 respectively). For eyes with flare photometry value at baseline <50ph/ms, there was no significant differences in specular microscopy results between the initial examination and the 1-month examination. CONCLUSIONS: In eyes with newly-diagnosed uveitis and active anterior chamber inflammation, specular microscopy shows transient qualitative abnormalities of the corneal endothelium that depend on the severity of the anterior chamber inflammation as measured by the laser flare meter.

[Retinal artery occlusion and anterior ischemic optic neuropathy associated with factor V Leiden mutation: A case report]. / Occlusion de l'artère centrale de la rétine associée à une neuropathie optique ischémique antérieure secondaire à une mutation du facteur V Leiden : à propos d'un cas.

Factor V is a pro-coagulant cofactor required for the transformation of prothrombin into thrombin. Thrombin activates factor V, which is then deactivated by protein C. A mutation in factor V is responsible for the formation of factor V Leiden, resistant to activated protein C. The association of this mutation with venous thromboses has been established. Its association with arterial occlusions is still controversial. We report the case of a central retinal artery occlusion associated with a non-arteritic anterior optic neuropathy associated with a Leiden mutation of factor V (FVL). The presence of FVL has been associated with lack of reperfusion and rapid progression to neovascularization. It seems that FVL intervenes mainly during the reperfusion phase after the occurrence of arterial thrombosis.

Evaluation of native microalgae from Tunisia using the pulse-amplitude-modulation measurement of chlorophyll fluorescence and a performance study in semi-continuous mode for biofuel production.

BACKGROUND: Microalgae are attracting much attention as a promising feedstock for renewable energy production, while simultaneously providing environmental benefits. So far, comparison studies for microalgae selection for this purpose were mainly based on data obtained from batch cultures, where the lipid content and the growth rate were the main selection parameters. The present study evaluates the performance of native microalgae strains in semi-continuous mode, considering the suitability of the algal-derived fatty acid composition and the saponifiable lipid productivity as selection criteria for microalgal fuel production. Evaluation of the photosynthetic performance and the robustness of the selected strain under outdoor conditions was conducted to assess its capability to grow and tolerate harsh environmental growth conditions. RESULTS: In this study, five native microalgae strains from Tunisia (one freshwater and four marine strains) were isolated and evaluated as potential raw material to produce biofuel. Firstly, molecular identification of the strains was performed. Then, experiments in semi-continuous mode at different dilution rates were carried out. The local microalgae strains were characterized in terms of biomass and lipid productivity, in addition to protein content, and fatty acid profile, content and productivity. The marine strain Chlorella sp. showed, at 0.20 1/day dilution rate, lipid and biomass productivities of 35.10 mg/L day and 0.2 g/L day, respectively. Moreover, data from chlorophyll fluorescence measurements demonstrated the robustness of this strain as it tolerated extreme outdoor conditions including high (38 °C) and low (10 °C) temperature, and high irradiance (1600 µmol/m2 s). CONCLUSIONS: Selection of native microalgae allows identifying potential strains suitable for use in the production of biofuels. The selected strain Chlorella sp. demonstrated adequate performance to be scaled up to outdoor conditions. Although experiments were performed at laboratory conditions, the methodology used in this paper allows a robust evaluation of microalgae strains for potential market applications.

Selection of native Tunisian microalgae for simultaneous wastewater treatment and biofuel production.

This paper focuses on the selection of native microalgae strains suitable for wastewater treatment and biofuel production. Four Chlorophyceae strains were isolated from North-eastern Tunisia. Their performances were compared in continuous mode at a 0.3 1/day dilution rate. The biomass productivity and nutrient removal capacity of each microalgae strain were studied. The most efficient strain was identified as Scenedesmus sp. and experiments at different dilution rates from 0.2 to 0.8 1/day were carried out. Maximal biomass productivity of 0.9 g/L day was obtained at 0.6 1/day. The removal of chemical oxygen demand (COD), ammonium and phosphorus was in the range of 92-94%, 61-99% and 93-99%, respectively. Carbohydrates were the major biomass fraction followed by lipids and then proteins. The saponifiable fatty acid content was in the 4.9-13.2% dry biomass range, with more than 50% of total fatty acids being composed of saturated and monosaturated fatty acids.

Halanaerobacter jeridensis sp. nov., isolated from a hypersaline lake.

An obligatory anaerobic, moderately halophilic bacterium, designated strain CEJFG43(T), was isolated from a sample of sediment collected below the salt crust on the hypersaline El Jerid lake, in southern Tunisia. The cells of this novel strain were Gram-staining-negative, non-sporulating, motile, short rods. They grew in media with 6-30% (w/v) NaCl (optimum 15%), at 20-60 °C (optimum 45 °C) and at pH 5.5-9.5 (optimum pH 8.3). The micro-organism fermented glucose, fructose, ribose, raffinose, galactose, mannose, sucrose, maltose, xylose, mannitol, pyruvate and glycerol. The products of glucose fermentation were lactate, ethanol, acetate, H(2) and CO(2). The genomic G+C DNA content of strain CEJFG43(T) was 33.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain CEJFG43(T) belonged in the genus Halanaerobacter and was most closely related to Halanaerobacter lacunarum DSM 6640(T) (95.3% gene sequence similarity) and Halanaerobacter chitinivorans DSM 9569(T) (95.3%). The predominant cellular fatty acids were non-branched (C(16:0) and C(16:1)). Based on the phylogenetic and phenotypic evidence, strain CEJFG43(T) represents a novel species in the genus Halanaerobacter for which the name Halanaerobacter jeridensis sp. nov. is proposed. The type strain is CEJFG43(T) ( = DSM 23230(T) = JCM 16696(T)).

Simultaneous hydrocarbon biodegradation and biosurfactant production by oilfield-selected bacteria.

AIMS: To study the bacterial diversity associated with hydrocarbon biodegradation potentiality and biosurfactant production of Tunisian oilfields bacteria. METHODS AND RESULTS: Eight Tunisian hydrocarbonoclastic oilfields bacteria have been isolated and selected for further characterization studies. Phylogenetic analysis revealed that three thermophilic strains belonged to the genera Geobacillus, Bacillus and Brevibacillus, and that five mesophilic strains belonged to the genera Pseudomonas, Lysinibacillus, Achromobacter and Halomonas. The bacterial strains were cultivated on crude oil as sole carbon and energy sources, in the presence of different NaCl concentrations (1, 5 and 10%, w/v), and at 37 or 55°C. The hydrocarbon biodegradation potential of each strain was quantified by GC-MS. Strain C450R, phylogenetically related to the species Pseudomonas aeruginosa, showed the maximum crude oil degradation potentiality. During the growth of strain C450R on crude oil (2%, v/v), the emulsifying activity (E24) and glycoside content increased and reached values of 77 and 1.33 g l(-1), respectively. In addition, the surface tension (ST) decreased from 68 to 35.1 mN m(-1), suggesting the production of a rhamnolipid biosurfactant. Crude biosurfactant had been partially purified and characterized. It showed interest stability against temperature and salinity increasing and important emulsifying activity against oils and hydrocarbons. CONCLUSIONS: The results of this study showed the presence of diverse aerobic bacteria in Tunisian oilfields including mesophilic, thermophilic and halotolerant strains with interesting aliphatic hydrocarbon degradation potentiality, mainly for the most biosurfactant produced strains. SIGNIFICANCE AND IMPACT OF THE STUDY: It may be suggested that the bacterial isolates are suitable candidates for practical field application for effective in situ bioremediation of hydrocarbon-contaminated sites.

[Treatment of olive mill wastewater by a process combining an intensive treatment (Jet-Loop reactor) followed by an extensive treatment (stabilization ponds)]. / Traitement des effluents d'huileries par un procédé combinant un traitement intensif (Jet-Loop reactor) suivi d'un traitement extensif (bassins de stabilisation).

Olive oil mill wastewater (OMW) is generally recognized as an environmentally troublesome by-product of the olive oil industry as its disposal without any treatment is known to cause serious environmental problems. However, this effluent has a high fertilizing power and constitutes, with urban wastewater, an important low-cost source. Biological treatment of OMW, with a process combining an aerobic reactor, 'Jet-Loop', and waste stabilization ponds, was investigated for possible agricultural reuse. The focus of the present study was to evaluate the contribution and the complementarity of the two systems in the total OMW treatment. Bio-treatment was performed using a 100-litre Jet-Loop reactor working volume achieving a chemical oxygen demand (COD) and phenolic compounds maximum removal rate of 72% and 68%, respectively, at a hydraulic retention time of 10 days. Co-treatment of OMW and domestic wastewater in waste stabilization ponds, with a hydraulic retention time of 22 days, reached a global removal rate of 66% for COD while no trace of phenolic compounds was detected on this level during the entire treatment period. Dynamics of faecal coliforms in stabilization ponds showed a total removal rate of 99.9% (3 logarithmic units (Log.U)). Preliminary results of agronomic tests on the ray-grass have evaluated the fertilizing effect of the final effluent resulting from the co-treatment.

Co-treatment of olive-mill and urban wastewaters by experimental stabilization ponds.

Olive oil mill wastewater (OMW) constitutes a source of environmental problems in Morocco due to its significantly high organic load, its phytotoxic properties and its relatively low biodegradability. An effective option for its disposal is its agricultural use after co-treatment with urban wastewater (UWW). The main objective of this investigation was to evaluate the potential of this co-treatment, using experimental waste stabilization ponds, in removing OMW phytotoxicity. We examined the influence of the organic load, at the entry of the treatment system, on the evolution of some physicochemical (chemical oxygen demand and polyphenols) and microbiological (fecal coliforms and fecal streptococci) parameters. The results showed a removal of the organic, phenolic and microbial load throughout the treatment which differed from one system to another according to the OMW load applied to each system. The results concerning the germination assays of Zea mays and Solanum lycopersicum suggested that the co-treatment of OMW with UWW would decrease the phytotoxicity of this waste.

Mesophilic and thermophilic anaerobic digestion of biologically pretreated abattoir wastewaters in an upflow anaerobic filter.

The hydrolysis pretreatment of abattoir wastewaters (AW), rich in organic suspended solids (fats and protein) was studied in static and stirred batch reactors without aeration in the presence of natural microbial population acclimated in a storage tank of AW. Microbial analysis showed that the major populations which contribute to the pretreatment of AW belong to the genera Bacillus. Contrary to the static pretreatment, the stirred conditions favoured the hydrolysis and solubilization of 80% of suspended matter into soluble pollution. The pretreated AW, in continuous stirred tank reactor (CSTR) at a hydraulic retention time (HRT) of 2 days, was fed to an upflow anaerobic filter (UAF) at an HRT of 2 days. The performance of anaerobic digestion of biologically pretreated AW was examined under mesophilic (37 degrees C) and thermophilic (55 degrees C) conditions. The shifting from a mesophilic to a thermophilic environment in the UAF was carried out with a short start-up of thermophilic condition. The UAF ran at organic loading rates (OLRs) ranging from 0.9 to 6g COD/Ld in mesophilic conditions and at OLRs from 0.9 to 9 g COD/Ld in thermophilic conditions. COD removal efficiencies of 80-90% were achieved for OLRs up to 4.5 g COD/Ld in mesophilic conditions, while the highest OLRs i.e. 9 g COD/Ld led to efficiencies of 70-72% in thermophilic conditions. The biogas yield in thermophilic conditions was about 0.32-0.45 L biogas/g of COD removed for OLRs up to 4.5 g COD/Ld. For similar OLR, the UAF in mesophilic conditions showed lower percentage of methanization. Mesophilic anaerobic digestion has been shown to destroy pathogens partially, whereas the thermophilic process was more efficient in the removal of indicator microorganisms and pathogenic bacteria at different organic loading rates.

Isolation and characterization of Halomonas sp. strain C2SS100, a hydrocarbon-degrading bacterium under hypersaline conditions.

AIMS: To isolate and characterize an efficient hydrocarbon-degrading bacterium under hypersaline conditions, from a Tunisian off-shore oil field. METHODS AND RESULTS: Production water collected from 'Sercina' petroleum reservoir, located near the Kerkennah island, Tunisia, was used for the screening of halotolerant or halophilic bacteria able to degrade crude oil. Bacterial strain C2SS100 was isolated after enrichment on crude oil, in the presence of 100 g l(-1) NaCl and at 37 degrees C. This strain was aerobic, Gram-negative, rod-shaped, motile, oxidase + and catalase +. Phenotypic characters and phylogenetic analysis based on the 16S rRNA gene of the isolate C2SS100 showed that it was related to members of the Halomonas genus. The degradation of several compounds present in crude oil was confirmed by GC-MS analysis. The use of refined petroleum products such as diesel fuel and lubricating oil as sole carbon source, under the same conditions of temperature and salinity, showed that significant amounts of these heterogenic compounds could be degraded. Strain C2SS100 was able to degrade hexadecane (C16). During growth on hexadecane, cells surface hydrophobicity and emulsifying activity increased indicating the production of biosurfactant by strain C2SS100. CONCLUSIONS: A halotolerant bacterial strain Halomonas sp. C2SS100 was isolated from production water of an oil field, after enrichment on crude oil. This strain is able to degrade hydrocarbons efficiently. The mode of hydrocarbon uptake is realized by the production of a biosurfactant which enhances the solubility of hydrocarbons and renders them more accessible for biodegradation. SIGNIFICANCE AND IMPACT OF THE STUDY: The biodegradation potential of the Halomonas sp. strain C2SS100 gives it an advantage for possibly application on bioremediation of water, hydrocarbon-contaminated sites under high-salinity level.

Low cost biosorbent "banana peel" for the removal of phenolic compounds from olive mill wastewater: kinetic and equilibrium studies.

The aim of this work is to determine the potential of application of banana peel as a biosorbent for removing phenolic compounds from olive mill wastewaters. The effect of adsorbent dosage, pH and contact time were investigated. The results showed that the increase in the banana peel dosage from 10 to 30 g/L significantly increased the phenolic compounds adsorption rates from 60 to 88%. Increase in the pH to above neutrality resulted in the increase in the phenolic compounds adsorption capacity. The adsorption process was fast, and it reached equilibrium in 3-h contact time. The Freundlich and Langmuir adsorption models were used for mathematical description of the adsorption equilibrium and it was found that experimental data fitted very well to both Freundlich and Langmuir models. Batch adsorption models, based on the assumption of the pseudo-first-order, pseudo-second-order and intraparticle diffusion mechanism, showed that kinetic data follow closely the pseudo-second-order than the pseudo-first-order and intraparticle diffusion. Desorption studies showed that low pH value was efficient for desorption of phenolic compounds. These results indicate clearly the efficiency of banana peel as a low-cost solution for olive mill wastewaters treatment and give some preliminary elements for the comprehension of the interactions between banana peel as a bioadsorbent and the very polluting compounds from the olive oil industry.

Potential use of Tunisian Pituranthos chloranthus essential oils as a natural disinfectant.

AIMS: To highlight the bactericidal and fungicidal activities of Tunisian Pituranthos chloranthus essential oils and to study their potential use as powerful and natural disinfectant. METHODS AND RESULTS: The essential oils were obtained by hydro-distillation of the aerial part of P. chloranthus. The bactericidal and fungicidal properties of essential oils were investigated by using the NCCLS broth dilution method and the EN 1275 and EN 1276 European standard methods. High bactericidal and fungicidal effects of 1.87-3.75 and 7.5 mg l(-1) were obtained, respectively. Essential oils concentrations of 0.5% and 1% (w/v) allowed reductions in viability higher than 5 and 4 log units per ml for standard bacteria and fungi, respectively, within a contact time of 5 min under dirty conditions. CONCLUSIONS: Our results support the traditional uses of P. chloranthus as a natural disinfectant and insecticide. It could be used to manage life-threatening pathogens as well as food preservative. SIGNIFICANCE AND IMPACT OF THE STUDY: This natural disinfectant could play a vital role in alleviating the spread of pathogenic micro-organisms and environmental problems associated with the indiscriminate use of synthetic chemicals.

Performance of biological treatment of high-level ammonia landfill leachate.

The biological treatment efficiency of landfill leachate (LFL) from a Tunisian site collection was investigated in this study. The raw effluent was highly charged with organic matter (more than 25 g l(-1) of chemical oxygen demand (COD)), ammonia (1.7 g l(-1) and salts (20 g l(-1)). With the presence of heavy metals, phenols and hydrocarbons, LFL exhibited high toxicity to organisms since it totally inhibited the bioluminescence of Vibrio fischeri and the germination of Lepidium sativum seeds. The biological oxygen demand (BOD5)/COD ratio of 0.5 indicates that the effluent can be biologically treated. Sludge from a wastewater treatment plant was acclimatized to the effluent in continuous batches. During the acclimatization phase, the consortia demonstrated a good ability to remove organic matter and toxicity in spite of an increase of introduced load reaching 3.2 g of COD 1.d. Consequently, the biodegradation experiments were carried out in a stirred tank reactor (STR) at organic loading rate (OLR) ranging from 0.5 to 5.4 g l(-1) per day. The hydraulic retention time was decreased from 50 days to 4.6 days. The process seemed to be efficient to eliminate organics and ammonia. The COD removal efficiency reached a maximum of 80% for a loading rate of 5.4 g l(-1) per day. The values of N-NH4+ became less than those recommended by standards requested for rejection in public canalizations. During the treatment process, the biomass was increased from 0.8 g l(-1) at the start-up of the process to 3 g l(-1). On the other hand, results of toxicity examinations showed that the treatment was efficient to provide detoxification of the effluent indicating a good adaptability of the consortia in spite of the presence of problematic compounds. The increase of the loading rate up to 6 g l(-1) was responsible for the perturbation of the system and caused an accumulation of residual COD and toxicity.

Involvement of microbial populations during the composting of olive mill wastewater sludge.

Olive mill waste water sludge obtained by the electro-Fenton oxidation of olive mill waste water was composted in a bench scale reactor. The evolution of microbial species within the composter was investigated using a respirometric test and by means of both cultivation-dependent and independent approaches (Polymerase Chain Reaction-Single Strand Conformation Polymorphism, PCR SSCP). During the period of high respiration rate (7-24 days), cultivation method showed that thermophilic bacteria as well as actinomycetes dominated over eumycetes. During the composting process, the PCR-SSCP method showed a higher diversity of the bacterial community than the eukaryotic one. After 60 days of composting, the compost exhibited a microbial stability and a clear absence of phytotoxicity.

Pilot-plant results of the electro-Fenton treatment of olive mill wastewaters followed by anaerobic digestion.

In this work, we investigated an integrated technology for the treatment of the recalcitrant contaminants of olive mill wastewaters (OMW), allowing water recovery and reuse for agricultural purposes. The method involves an electrochemical pre-treatment step of the wastewater using the electro-Fenton reaction followed by an anaerobic bio-treatment. The electro-Fenton pre-treatment process removed 66% of the total polyphenolic compounds and subsequently decreased the OMW toxicity from 100 to 66.9%, which resulted in improving the performance of the anaerobic digestion. A continuous laboratory-scale methanogenic reactor was operated at a loading rate of 10g COD/L per day without any apparent toxicity. Furthermore, in the combined process, a high overall reduction in COD, suspended solids, polyphenols and lipids content was achieved by the two successive stages. Moreover, this combined process which was experimented at a real scale (25 m3 digester) demonstrated its technical feasibility and opens promising perspectives for industrial application in the Mediterranean countries because of its easy conception and high energy (methane) production.

Pilot-plant results of the electro-Fenton treatment of olive mill wastewaters followed by anaerobic digestion.

In this work, we investigated an integrated technology for the treatment of the recalcitrant contaminants of olive mill wastewaters (OMW), allowing water recovery and reuse for agricultural purposes. The method involves an electrochemical pre-treatment step of the wastewater using the electro-Fenton reaction followed by an anaerobic bio-treatment. The electro-Fenton pre-treatment process removed 66% of the total polyphenolic compounds and subsequently decreased the OMW toxicity from 100 to 66.9% which resulted in improving the performance of the anaerobic digestion. A continuous lab-scale methanogenic reactor was operated at a loading rate of 10 g COD/L day without any apparent toxicity. Furthermore, in the combined process, a high overall reduction in COD, suspended solids, polyphenols and lipids content was achieved by the two successive stages. Moreover, this combined process which was experimented at a real scale (25 m3 digester), demonstrated its technical feasibility and opens promising perspectives for industrial application in the Mediterranean countries due to its easy conception and its high energy (methane) production.

Purification and characterization of the laccase secreted by the white rot fungus Perenniporia tephropora and its role in the decolourization of synthetic dyes.

AIMS: To characterize the white rot fungus Perenniporia tephropora with respect to its laccase and to test its ability to decolourize synthetic dyes. METHODS AND RESULTS: Under the culture conditions utilized, P. tephropora produced one laccase isozyme, which was purified to electrophoretic homogeneity by ammonium sulfate precipitation, size-exclusion chromatography and anion-exchange chromatography. The protein was monomeric with a molecular mass of 63 kDa (SDS-PAGE) and had an isoelectric point of 3.3. The N-terminal amino acid sequence was SIGPVADLTVTNANI and the highest similarity value was found to the laccase from Lentinus tigrinus (86.6%). The optimum pH of the enzyme varied and was substrate dependent. It was 4.0 and 5.0 for 2,6-dimethoxyphenol (DMP) and 2,2'-azino-di(3-ethyl-benzthiazoline-6-sulfonate) (ABTS), respectively. Under standard assay conditions, K(m) values of the enzyme were 7.3 and 0.4 mmol l(-1) towards DMP and ABTS, respectively. The laccase was inhibited by NaN(3), EDTA and p-coumarate but not by SDS and NaBr. Laccase was stable in the presence of some metal ions such as Cu(2+), Co(2+), Ca(2+), Cd(2+), Mg(2+), Mn(2+), Mo(2+), Ni(2+), Li(+) and Al(3+). The crude enzyme as well as the purified laccase was able to decolourize dyes from the textile industries, including remazol brilliant blue R, neolane blue and neolane pink. However, several other dyes were partially or not decolourized. In the presence of 1-hydroxybenzotriazole as mediator, only the decolourization of neolane yellow was achieved, while the decolourization of most of the dyes was just slightly improved. SIGNIFICANCE AND IMPACT OF THE STUDY: This study is the first report on the purification and the characterization of the laccase from the white rot fungus P. tephropora. The high levels of laccase secreted by this fungal strain as well as its stability suggest that it could be a useful tool for environmental applications.

A comparative study on the anaerobic membrane bioreactor performance during the treatment of domestic wastewaters of various origins.

This study examined the practical performance of a cross-flow ultrafiltration membrane coupled to an anaerobic bioreactor, for treatment of raw domestic wastewater (RDW), at a pilot-scale plant. Wastewaters used in this study originated from two different domestic wastewater treatment plans (DWTPs) (Sfax and Ksour Essef). During the treatment in the membrane bioreactor (MBR) of the RDW originating from Sfax DWTP, the bioreactor did not reach its stationary phase because the anaerobic biomass was unable to adapt to the wastewater. This was explained by the considerable fluctuations in the domestic wastewater composition and a possible contamination of Sfax wastewater by industrial discharges. However, the treatment of RDW originating from Ksour Essef (DWTP) was successful. In both cases, the treatment led to a total removal of all tested pathogens. The quality of treated wastewater fits largely with WHO guidelines for unrestricted irrigation. The phytotoxicity and the microtoxicity tests, using Lepidium sativum and Vibrio fischeri respectively, demonstrated that wastewater from Sfax exhibited higher toxicity than that from Ksour Sssef.

[Laser coagulation in the endoscopic management of fourth branchial pouch sinus]. / Traitement endoscopique au laser des fistules de la 4e poche endobranchiale.

OBJECTIVES: To describe a new method of treatment of the fourth branchial pouch sinuses by laser endoscopic coagulation of the fistula. MATERIAL AND METHODS: Retrospective study of two children aged 3 and 12 years with fourth branchial pouch sinuses. Both children presented recurrent cervical abscesses. The diagnosis was established on results of ultrasound, barium study, CT scan and pharyngoscopy. After recovering from infection, the definitive treatment was a laser diode cauterization of the fistulous route and its pharyngeal opening. RESULTS: Outcome was rapidly favorable in both children without complications or recurrence. DISCUSSION: These two cases and other reports in the literature confirm the role of endoscopic management for the treatment of the fourth branchial pouch sinus. Laser treatment is especially useful because of its convenience, its harmlessness and its reliability. CONCLUSION: Fourth branchial pouch sinuses are rare. Surgery, which can be difficult and not without risks, is the generally accepted treatment. This new laser method combines ease of treatment and efficacy.