Bioinformatic analysis of the genome of infectious salmon anemia virus associated with outbreaks with high mortality in Chile.

The infectious salmon anemia virus (ISAV), an orthomyxovirus, is the major cause of outbreaks of high mortality rates in salmon in Chile. It has been proposed that the virulence of ISAV isolates lies mainly in hemagglutinin-esterase and fusion glycoproteins. However, based on current information, the contribution of other viral genes cannot be ruled out. To study this, we isolated and determined the complete coding sequence of two high-prevalence Chilean isolates associated with outbreaks of high mortality rates: ISAV752_09 and ISAV901_09. These isolates were compared to 15 Norwegian isolates that exhibit differences in their virulence. For this purpose, we performed bioinformatic analyses of (i) functional domains, (ii) specific mutations, (iii) Bayesian phylogenetics, and (iv) structural comparisons between ISAV and influenza virus glycoproteins by using molecular modeling. Phylogenetic analysis shows two genogroups for each protein, one of them containing the Chilean isolates. The gene sequence of the polymerase complex and nucleoprotein indicated that they are closely related to homologues from highly pathogenic Norwegian viruses. Notably, seven of the eight mutations that are present only in the Chilean isolates are on the polymerase complex and nucleoprotein. Structural modeling of hemagglutinin-esterase shows patches of variable residues on its surface. Fusion protein modeling shows that insertions are flexible regions that could affect proteolytic processing, increasing either the accessibility or the number of recognition sites for specific proteases. We found antigenic drift processes related to insertion into the isolated segment 5 of the ISAV752_09. Our results confirm the European origin of Chilean isolates to be the result of reassortments from Norwegian ancestors.

Removal of methylene blue from colored effluents by adsorption on montmorillonite clay.

In this study, montmorillonite clay (MC) has been utilized as the adsorbent for the removal of a cationic dye, methylene blue (MB), from aqueous solution by the batch adsorption technique under different conditions of initial dye concentration, adsorbent concentration, contact time, solution pH, and temperature. Attempts were made to fit the isothermal data using Langmuir and Freundlich equations. The experimental results have demonstrated that the equilibrium data are fitted well by a Langmuir isotherm equation. Thermodynamic parameters such as the changes in enthalpy, entropy, and Gibbs' free energy were determined, showing adsorption to be an endothermic yet spontaneous process. Pseudo-first-order, pseudo-second-order, and intraparticle diffusion models were considered to evaluate the rate parameters. The experimental data fitted the pseudo-second-order kinetic model, with an activation energy of +28.5 kJ mol(-1). The results indicate that MC adsorbs MB efficiently and could be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.

HSV2 acute retinal necrosis: diagnosis and monitoring with quantitative polymerase chain reaction.

PURPOSE: To describe a case of HSV2 acute retinal necrosis (ARN) diagnosed and monitored with quantitative polymerase chain reaction (PCR) in ocular fluids. DESIGN: Case report. METHODS: Quantitative PCR was performed in the aqueous humor (AH) and vitreous using primers specific for herpes virus. RESULTS: A positive PCR was found for HSV2 in the AH (>100,000,000 viral copies - 8.00 log/ml). After therapy, another anterior chamber tap showed a reduction of the viral load at 4.28 log/ml (19205 copies), confirming the efficacy of the treatment. After six months, PCR on the vitreous still showed the presence of HSV2 viral particles in the eye (3.14 log DNA copies/ml, 1379 copies) although the lesion was healed. CONCLUSIONS: This case demonstrates that PCR is useful to detect viral DNA in AH and vitreous and to monitor viral activity and therapeutic response. Viral DNA persists in ocular fluids for months in the presence of a healed infection.

[Evaluation of the anterior chamber depth after cataract surgery with OCT Visante]. / Evaluation de la profondeur de la chambre antérieure après chirurgie de la cataracte avec l'OCT Visante.

INTRODUCTION: OCT Visante allows the visualisation of the anterior segment structures and particularly of the irido-corneal angle by a non-contact method. We made a prospective study on 14 patients to demonstrate by OCT Visante the changes of irido-corneal angle and depth of the anterior chamber after cataract surgery. PATIENTS AND METHODS: 14 eyes of 14 patients have undergone a phacoemulsification of the cataract with posterior chamber lens implantation. All patients have had a complete ophthalmologic examination, an OCT Visante with angle measurement and an A-Scan for determination of the lens thickness. All these exams were repeated at 1 week and 1 month postoperatively. RESULTS: In all patients, we noticed an increase of the postoperative iridocorneal angle. The mean preoperative angle was 18.3 degrees +/- 11.81 SD, 38.65 degrees +/- 3.95 SD at 1 week postoperatively and 45.7 degrees +/- 8.72 SD at 1 month. DISCUSSION: Imagery by OCT Visante allowed us by a non-invasive method to quantify very precisely the opening of the irido-corneal angle and the increase of the anterior chamber depth after cataract surgery. OCT Visante is a method allowing the visualisation and quantification of anterior segment changes after cataract surgery.