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Chromium and salt tolerance in five indigenous cyanobacterial strains isolated from contaminated sites was investigated along with their metal bioaccumulative potential. All the five species showed significantly better growth when the medium was spiked with salt or chromium. As compared to single metal or salt treatment, the binary metal–salt (MS) treatments had more favorable effect on cyanobacterial growth as indicated by significantly higher concentration of the primary photosynthetic pigment chlorophyll at M20S2000 (9.9–25.3 μg/mL) as compared to that at M0S0 (4.0–12.3 μg/mL). Similarly biomass was much higher at M20S1000 and M20S2000 (41.8–86.2 mg/10 mL) as compared to that at control, M0S0 (21.5–36.3 mg/10 mL). Accessory pigments like carotenoids and phycobilinproteins too tended to increase significantly in response to both metal and salts in the two species of Lyngbya (L. putealis and L. ceylanica var. constricta) and Gloeocapsa. These species also showed greater potential of chromium bioaccumulation, which increased further as both salt and metal concentration increased. In the two species of Nostoc however, bioaccumulative potential improve at higher metal concentration, but not affected significantly by salt concentration.

This paper presents the chromium adsorptive potential of polysaccharide produced by a novel cyanobacterium Lyngbya putealis HH-15. Batch mode experiments were performed to determine the adsorption equilibrium and the equilibrium data was applied to different two-parameter models (Langmuir, Freundlich, Temkin, Dubinin–Radushkevich, Flory–Huggins, and Brunauer, Emmer & Teller (BET) model). The highest coefficient of determination (0.9925) for Langmuir and BET models indicates best fitness of these models in explaining the sorption as a multilayer process. Effect of different variables like initial metal ion concentration (10–100 mg/L), pH (2–6) and temperature (25–45 °C) on chromium adsorption of exopolysaccharides (EPS) were also examined, using Box–Behnken design model. Very high value of regression coefficient between the variables and the response (R2 = 0.9982) indicates excellent evaluation of experimental data by second-order polynomial regression model. The response surface method indicated that 30–40 mg/L initial chromium concentration, pH 2 and 45 °C temperature were optimal for biosorption of chromium by the cyanobacterial exopolysaccharides. Adsorption capacity of EPS increased from 45 to 157 mg/g of EPS as initial Cr(VI) concentration increased from 10 to 30 mg/L. Surface adsorption of the metal at surface of EPS was confirmed through scanning electron microscopy.

The potential use of alginate immobilized algal beads for the removal of chromium from aqueous solution has been investigated under optimized conditions in this study using a novel cyanobacterium, Lyngbya putealis isolated from metal contaminated soil. Batch mode experiments were performed to determine the adsorption equilibrium and kinetic behaviour of chromium in aqueous solution allowing the computation of kinetic parameters and maximum metal adsorption capacity. Influences of other parameters like initial metal ion concentration (10–100 mg/L), pH (2–6) and temperature (25–45 °C) on chromium adsorption were also examined, using Box–Behnken design. Very high regression coefficient between the variables and the response ( R 2 = 0.9984) indicates excellent evaluation of experimental data by second-order polynomial regression model. The response surface method indicated that 50–60 mg/L initial chromium concentration, 2–3 pH and a temperature of 45 °C were optimal for biosorption of chromium by immobilized L. putealis , when 82% of the metal is removed from the solution.

Keywords: VRE – HLAR – Quinpristin/Dalfopristin. Submitted by ROBERTO PAULO CORREIA DE ARAÚJO (ppgorgsistem@ufba.br) on 2016-09-15T17:33:08Z No. of bitstreams: 1 4_v.8_1.pdf: 123228 bytes, checksum: 3d3f30c7a8434b2e4dbb2eb114a43cb7 (MD5) Made available in DSpace on 2016-09-15T17:33:08Z (GMT). No. of bitstreams: 1 4_v.8_1.pdf: 123228 bytes, checksum: 3d3f30c7a8434b2e4dbb2eb114a43cb7 (MD5) Previous issue date: 2009-01 Abstract: During the last few years enterococci have emerged as an important cause of nosocomial and community acquired infection. They have acquired resistance to commonly used antibiotics including glycopeptides posing challenge to therapeutic options. The aim of this study was to investigate the prevalence and sensitivity of VRE to newer drugs. A total of 250 strains of E. faecalis were isolated using conventional scheme of Facklam and Collins. High level aminoglycoside resistance (HLAR) was detected by disc diffusion method using 120 μg gentamicin disc and confirmed by agar dilution screen method. Screening for vancomycin resistance was done by disc diffusion and the agar screen method, and was further confirmed by broth dilution method for minimum inhibitory concentration (MIC). The strains which were resistant to vancomycin were further tested for sensitivity to newer and commonly available antibiotics. Maximum number of enterococcal isolates were recovered from urine (32.8%) followed by blood (25.6%) and pus (18.4%). Penicillin (83.6%) and cotrimoxazole (77.9%) were found to be least effective drugs against the E. faecalis whereas; cefuroxime (76.8%) and vancomycin (98%) were most effective drugs in vitro. About two percent isolates of enterococci were resistant to vancomycin. All the VRE isolates were sensitive to quinupristin/dalfopristin. Linezolid and chloramphenicols were the two other in vitro effective drugs with 80% sensitive isolates. MIC of all the VRE isolates was found to be in range of 64-512μg/mL. So, quinupristin/dalfopristin can be used for infections caused by VRE. Continuous surveillance is necessary to detect early outbreak, and spread of VRE.Abstract During the last few years enterococci have emerged as an important cause of nosocomial and community acquired infection. They have acquired resistance to commonly used antibiotics including glycopeptides posing challenge to therapeutic options. The aim of this study was to investigate the prevalence and sensitivity of VRE to newer drugs. A total of 250 strains of E. faecalis were isolated using conventional scheme of Facklam and Collins. High level aminoglycoside resistance (HLAR) was detected by disc diffusion method using 120 μg gentamicin disc and confirmed by agar dilution screen method. Screening for vancomycin resistance was done by disc diffusion and the agar screen method, and was further confirmed by broth dilution method for minimum inhibitory concentration (MIC). The strains which were resistant to vancomycin were further tested for sensitivity to newer and commonly available antibiotics. Maximum number of enterococcal isolates were recovered from urine (32.8%) followed by blood (25.6%) and pus (18.4%). Penicillin (83.6%) and cotrimoxazole (77.9%) were found to be least effective drugs against the E. faecalis whereas; cefuroxime (76.8%) and vancomycin (98%) were most effective drugs in vitro. About two percent isolates of enterococci were resistant to vancomycin. All the VRE isolates were sensitive to quinupristin/dalfopristin. Linezolid and chloramphenicols were the two other in vitro effective drugs with 80% sensitive isolates. MIC of all the VRE isolates was found to be in range of 64-512μg/mL. So, quinupristin/dalfopristin can be used for infections caused by VRE. Continuous surveillance is necessary to detect early outbreak, and spread of VRE. Salvador

Keywords: VRE – HLAR – Quinpristin/Dalfopristin. Submitted by ROBERTO PAULO CORREIA DE ARAÚJO (ppgorgsistem@ufba.br) on 2016-09-15T17:33:08Z No. of bitstreams: 1 4_v.8_1.pdf: 123228 bytes, checksum: 3d3f30c7a8434b2e4dbb2eb114a43cb7 (MD5) Made available in DSpace on 2016-09-15T17:33:08Z (GMT). No. of bitstreams: 1 4_v.8_1.pdf: 123228 bytes, checksum: 3d3f30c7a8434b2e4dbb2eb114a43cb7 (MD5) Previous issue date: 2009-01 Abstract: During the last few years enterococci have emerged as an important cause of nosocomial and community acquired infection. They have acquired resistance to commonly used antibiotics including glycopeptides posing challenge to therapeutic options. The aim of this study was to investigate the prevalence and sensitivity of VRE to newer drugs. A total of 250 strains of E. faecalis were isolated using conventional scheme of Facklam and Collins. High level aminoglycoside resistance (HLAR) was detected by disc diffusion method using 120 μg gentamicin disc and confirmed by agar dilution screen method. Screening for vancomycin resistance was done by disc diffusion and the agar screen method, and was further confirmed by broth dilution method for minimum inhibitory concentration (MIC). The strains which were resistant to vancomycin were further tested for sensitivity to newer and commonly available antibiotics. Maximum number of enterococcal isolates were recovered from urine (32.8%) followed by blood (25.6%) and pus (18.4%). Penicillin (83.6%) and cotrimoxazole (77.9%) were found to be least effective drugs against the E. faecalis whereas; cefuroxime (76.8%) and vancomycin (98%) were most effective drugs in vitro. About two percent isolates of enterococci were resistant to vancomycin. All the VRE isolates were sensitive to quinupristin/dalfopristin. Linezolid and chloramphenicols were the two other in vitro effective drugs with 80% sensitive isolates. MIC of all the VRE isolates was found to be in range of 64-512μg/mL. So, quinupristin/dalfopristin can be used for infections caused by VRE. Continuous surveillance is necessary to detect early outbreak, and spread of VRE.Abstract During the last few years enterococci have emerged as an important cause of nosocomial and community acquired infection. They have acquired resistance to commonly used antibiotics including glycopeptides posing challenge to therapeutic options. The aim of this study was to investigate the prevalence and sensitivity of VRE to newer drugs. A total of 250 strains of E. faecalis were isolated using conventional scheme of Facklam and Collins. High level aminoglycoside resistance (HLAR) was detected by disc diffusion method using 120 μg gentamicin disc and confirmed by agar dilution screen method. Screening for vancomycin resistance was done by disc diffusion and the agar screen method, and was further confirmed by broth dilution method for minimum inhibitory concentration (MIC). The strains which were resistant to vancomycin were further tested for sensitivity to newer and commonly available antibiotics. Maximum number of enterococcal isolates were recovered from urine (32.8%) followed by blood (25.6%) and pus (18.4%). Penicillin (83.6%) and cotrimoxazole (77.9%) were found to be least effective drugs against the E. faecalis whereas; cefuroxime (76.8%) and vancomycin (98%) were most effective drugs in vitro. About two percent isolates of enterococci were resistant to vancomycin. All the VRE isolates were sensitive to quinupristin/dalfopristin. Linezolid and chloramphenicols were the two other in vitro effective drugs with 80% sensitive isolates. MIC of all the VRE isolates was found to be in range of 64-512μg/mL. So, quinupristin/dalfopristin can be used for infections caused by VRE. Continuous surveillance is necessary to detect early outbreak, and spread of VRE. Salvador

The present study reports on chromium (VI) tolerance of two cyanobacterial strains Nostoc linckia and Nostoc spongiaeforme isolated from salt affected soils using uni-algal and bi-algal systems. Besides distinct halophilism, the two strains exhibited remarkable tolerance to chromium (VI) and revealed 1.2 to 2.8 times more chlorophyll in the presence of the metal. While phycobilins and carotenoids also increased in Nostoc linckia with total dissolved salts (TDS) as well as metal, a decline was observed in Nostoc spongiaeforme in the presence of Cr (VI). Relative algal biomass (as % of control) showed significantly higher values (123-239) in Nostoc linckia in the presence of salt, metal and combination of the two. In Nostoc spongiaeforme it declined in the presence of metal (72-81) but increased in the presence of salts (143-249) and also in the binary systems (121-440). The bi-algal consortium showed relatively less tolerance to salt and metal stress. Nostoc linckia (20 day culture) showed upto 40% chromium removal whereas Nostoc spongiaeforme showed up to 12% removal, indicating greater suitability of the former for use in bioremediation studies.

Industrial wastewaters containing heavy metals along with high concentration of soluble salts pose a major environmental problem that needs to be remedied. The present study reports on biosorption of Cr(VI) by native isolate of Lyngbya putealis HH-15 in batch system under varying range of pH (2.0–10.0), initial metal ion concentration (10–100 mg/l) and salt concentration (0–0.2%). Maximum metal removal (94.8%) took place at pH 3.0 with initial Cr concentration of 50 mg/l, which got reduced (90.1%) in the presence of 0.2% salts. Adsorption equilibrium and kinetic behavior of Cr(VI) in solution was also examined. Both Langmuir and Freundlich models fitted well to explain the adsorption data ( R 2 = 0.90 and 0.87, respectively) at 0.2% salt concentration. Pseudo-second order kinetic model also fitted well to both the systems, viz. Cr(VI) and Cr(VI) + salt.

32 year old male presented with right facial palsy following head injury. Clinical evaluation showed hemotympanum on right with moderately severe conductive hearing loss, grade III LMN facial palsy and BPPV. HRCT of temporal bone demonstrated fracture base of skull involving the roof of mastoid with no evidence of bony injury to fallopian canal. Conservative management of head trauma resulted in satisfactory outcome except for conductive hearing loss and faciel palsy. Facial palsy was managed conservatively [physiotherapy and oral steroids] with full recovery of function after 4 weeks. Conductive hearing loss was managed by combined approach tympanaplasty. Preoperutively incudostapedial joint dislocation and fracture anterior crus of stapes were noted. Type II tympanoplasty with horizontal incus repositioning was carried out.PTA after 6 weeks showed 15-20 dB air-bone gap compared to 50-55dB air-bone gap preoperatively. BPPV recovered spontaneously. This case is reported to highlight:Importance of imaging of temporal bone.Spontaneous recovery of facial nerve function in neuropraxtc injury.Timely and appropriate surgical intervention of ossicular damage following head injury resulting in satisfatctory outcome.