Novel surface modified hydrous zirconium oxide with b cyclodextrin composite (CY-HZO) preparation... more Novel surface modified hydrous zirconium oxide with b cyclodextrin composite (CY-HZO) preparation. Significantly higher capacity of fluoride adsorption of CY-HZO than pristine HZO. Efficient, economical and eco-friendly fluoride remediation possible. Fluoride adsorption by CY-HZO via ion-exchange. About 95% reactivation of used CY-HZO is possible with 3 M NaOH. a b s t r a c t Surface modified hydrous zirconium oxide (HZO) with b-cyclodextrin (b-CD) material (CY-HZO) was characterized as micro-structured (150 nm), predominantly amorphous with irregular and undulated surface morphology using analytical tools such as XRD, SEM, TEM, AFM,BET surface analysis etc. Too high surface site concentrations of CY-HZO (6300 nm À2) compared to pristine HZO (26 nm À2) is owing to the abundance of surface –OH groups afforded by b-CD, which plays a decisive role in enhancing fluoride adsorption power of HZO. Fluoride adsorption over CY-HZO shows a discernible rise up to a pH $ 5.0, and declines sharply at pH > 6.0. Kinetically pseudo second order type fluoride adsorption reactions with CY-HZO and HZO were isothermally Langmuir type but endothermic with CY-HZO and exothermic with HZO. But both were spontaneous (ÀDG 0 = 1.78, 2.06 & 5.18 for CY-HZO and 3.14, 3.0 & 2.66 for HZO at T = 303, 318 and 333 K). Langmuir capacity (q m , mg g À1) of CY-HZO (31.45) is significantly higher than HZO (22.45) at 303 K. About 95% of the adsorbed fluoride could be released from CY-HZO surface by 3.0 M NaOH solution. Thus, CY-HZO should be a more potent material than HZO for fluoride removal from aqueous media.
Purpose To study the incidence, clinical presentation, and the response of anti-fungals in cases ... more Purpose To study the incidence, clinical presentation, and the response of anti-fungals in cases of fungal endophthalmitis following open globe injury. Methods This is a prospective study of eight cases of post-traumatic fungal endophthalmitis among 110 patients who presented to us with open globe injury between August 2003 and January 2005. Patients with panophthalmitis were eviscerated and rest received intravitreal amphotericin B. Pars plana vitrectomy along with intravitreal miconazole was given in patients with inadequate response to intravitreal amphotericin. Results Two patients had panophthalmitis at the time of presentation and were eviscerated. Six different organisms were isolated from the culture of intraocular specimen of eight patients. The yield of vitreous aspirate was 87.5% and that of aqueous aspirate was 66.6%. Aspergillus sp. and Fusarium sp. were isolated in 62.5% of cases. Minimum inhibitory concentration of amphotericin B and miconazole was less than 3 lg/ml for all organisms except for Paecilomyces lilacinus and Fusarium solani, respectively. In total, 37.5% of patient had final visual acuity of 20/400 or better. Conclusions Fungal endophthalmitis is a relatively rare complication of open globe injury. The final visual outcome after fungal endophthalmitis is dismal. Aspergillus fumigatus was found to be the most virulent organism. All organisms were found to be sensitive to amphotericin B, except P. lilacinus, which was sensitive to miconazole. Repeated intravitreal injection may be required to control the infection. The virulence of the organism and the site of injury are the main determinants of final visual outcome.
Novel surface modified hydrous zirconium oxide with b cyclodextrin composite (CY-HZO) preparation... more Novel surface modified hydrous zirconium oxide with b cyclodextrin composite (CY-HZO) preparation. Significantly higher capacity of fluoride adsorption of CY-HZO than pristine HZO. Efficient, economical and eco-friendly fluoride remediation possible. Fluoride adsorption by CY-HZO via ion-exchange. About 95% reactivation of used CY-HZO is possible with 3 M NaOH. a b s t r a c t Surface modified hydrous zirconium oxide (HZO) with b-cyclodextrin (b-CD) material (CY-HZO) was characterized as micro-structured (150 nm), predominantly amorphous with irregular and undulated surface morphology using analytical tools such as XRD, SEM, TEM, AFM,BET surface analysis etc. Too high surface site concentrations of CY-HZO (6300 nm À2) compared to pristine HZO (26 nm À2) is owing to the abundance of surface –OH groups afforded by b-CD, which plays a decisive role in enhancing fluoride adsorption power of HZO. Fluoride adsorption over CY-HZO shows a discernible rise up to a pH $ 5.0, and declines sharply at pH > 6.0. Kinetically pseudo second order type fluoride adsorption reactions with CY-HZO and HZO were isothermally Langmuir type but endothermic with CY-HZO and exothermic with HZO. But both were spontaneous (ÀDG 0 = 1.78, 2.06 & 5.18 for CY-HZO and 3.14, 3.0 & 2.66 for HZO at T = 303, 318 and 333 K). Langmuir capacity (q m , mg g À1) of CY-HZO (31.45) is significantly higher than HZO (22.45) at 303 K. About 95% of the adsorbed fluoride could be released from CY-HZO surface by 3.0 M NaOH solution. Thus, CY-HZO should be a more potent material than HZO for fluoride removal from aqueous media.
Purpose To study the incidence, clinical presentation, and the response of anti-fungals in cases ... more Purpose To study the incidence, clinical presentation, and the response of anti-fungals in cases of fungal endophthalmitis following open globe injury. Methods This is a prospective study of eight cases of post-traumatic fungal endophthalmitis among 110 patients who presented to us with open globe injury between August 2003 and January 2005. Patients with panophthalmitis were eviscerated and rest received intravitreal amphotericin B. Pars plana vitrectomy along with intravitreal miconazole was given in patients with inadequate response to intravitreal amphotericin. Results Two patients had panophthalmitis at the time of presentation and were eviscerated. Six different organisms were isolated from the culture of intraocular specimen of eight patients. The yield of vitreous aspirate was 87.5% and that of aqueous aspirate was 66.6%. Aspergillus sp. and Fusarium sp. were isolated in 62.5% of cases. Minimum inhibitory concentration of amphotericin B and miconazole was less than 3 lg/ml for all organisms except for Paecilomyces lilacinus and Fusarium solani, respectively. In total, 37.5% of patient had final visual acuity of 20/400 or better. Conclusions Fungal endophthalmitis is a relatively rare complication of open globe injury. The final visual outcome after fungal endophthalmitis is dismal. Aspergillus fumigatus was found to be the most virulent organism. All organisms were found to be sensitive to amphotericin B, except P. lilacinus, which was sensitive to miconazole. Repeated intravitreal injection may be required to control the infection. The virulence of the organism and the site of injury are the main determinants of final visual outcome.
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