Decolorization of different textile dyes by Penicillium simplicissimum and toxicity evaluation after fungal treatment

The objective of this study was to investigate the capacity of decolorization and detoxification of the textile dyes Reactive Red 198 (RR198), Reactive Blue 214 (RB214), Reactive Blue 21 (RB21) and the mixture of the three dyes (MXD) by Penicillium simplicissimum INCQS 40211. The dye RB21, a phthalocyanine, was totally decolorized in 2 days, and the others, the monoazo RR198, the diazo RB214 and MXD were decolorized after 7 days by P. simplicissimum. Initially the dye decolorization involved dye adsorption by the biomass followed by degradation. The acute toxicity after fungal treatment was monitored with the microcrustacean Daphnia pulex and measured through Effective Concentration 50 percent (EC50). P. simplicissimum reduced efficiently the toxicity of RB21 from moderately acutely toxic to minor acutely toxic and it also reduced the toxicity of RB214 and MXD, which remained minor acutely toxic. Nevertheless, the fungus increased the toxicity of RR198 despite of the reduction of MXD toxicity, which included this dye. Thus, P. simplicissimum INCQS 40211 was efficient to decolorize different textile dyes and the mixture of them with a significant reduction of their toxicity. In addition this investigation also demonstrated the need of toxicological assays associated to decolorization experiments.

Lift-up laminoplasty for myelopathy caused by ossification of the posterior longitudinal ligament of the cervical spine.

BACKGROUND AND AIMS: We have utilized lift-up laminoplasty to treat patients with myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) of the cervical spine. The preliminary surgical outcome with computer-assisted morphological assessment is presented. MATERIAL AND METHODS: The surgical technique of lift-up laminoplasty includes standard posterior exposure of the cervical spine, en-bloc laminectomy, and expansion of the cervical canal by lift-up of the laminae with custom-designed hydroxyapatite laminar spacers and stabilization of the laminae using titanium miniplates. From 1998 to 2003, 10 consecutive patients with cervical myelopathy secondary to OPLL have been treated with this method and comprehensively evaluated. Care was taken to tailor the treatment to individual patients by using different sizes of spacers to adjust the degree of expansion depending on the amount of stenosis of the cervical spine. The degree of expansion of the cervical canal was altered by design, based on the preoperative imaging simulation. RESULTS: Preliminary surgical outcome, evaluated at 6 months after surgery, revealed a significant improvement of neurological function. Image analysis revealed that the cervical canals were significantly expanded, with a mean reduction of 13.1% in the stenosis ratio. Lift-up laminoplasty was effective in the treatment of patients with myelopathy secondary to cervical OPLL, and the amount of expansion could be individually adjusted at the discretion of the surgeon. CONCLUSION: Although analysis with a larger population and a longer follow-up period needs to be undertaken, our method of lift-up laminoplasty appears to be a viable choice among standard posterior cervical approaches for cervical OPLL.