Bahram Sarkarati | Abant Izzet Baysal University, Bolu, Turkey (original) (raw)
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Papers by Bahram Sarkarati
Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology, 1999
Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with ... more Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with a procedure including ammonium sulfate fractionation (55-70%) with acid step at pH 4.5 and procainamide-Sepharose 4B affinity chromatography. The purified enzyme exhibited negative cooperativity with respect to butyrylthiocholine (BTCh) binding at pH 7.5. Ks was found to be 0.128 +/- 0.012 mM. Inhibition kinetics of the enzyme by Cd2+, Zn2+ and Al3+ were studied in detail. The 1/v vs 1/[BTCh] plots in the absence (control plot) and in the presence of different concentrations of cations intersected above 1/[BTCh]-axis. The data were analyzed by means of a nonlinear curve fitting program. The results demonstrated that all of the three cations are the linear mixed-type inhibitors of BChE. Ca2+ and Mg2+ had no effect on the enzyme activity in the experimental conditions. But when the enzyme was inhibited by 0.5 mM Cd2+ or Zn2+, Ca2+ and Mg2+ partially reactivated the inhibited allosteric form of BChE. Results were compared with data obtained from brain BChE purified from sheep.
Turkish Neurosurgery, 2012
AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognize... more AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. mAterIAl and methOds: After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes. results: There were statistically significant differences among the groups regarding the comparison of the values of the PMNL cell infiltration grades, gliosis and congestion in both acute and chronic stages. However, the values of the MNL cell infiltration grades, edema and fibrin formation, lipid peroxidation levels of harvested brain tissues were similar in all groups. COnClusIOn: Although this study did not present the detailed histopathological and biochemical evaluation results, it indicated that the application of the PEG-based hydrogel sealant was not associated with neurotoxicity, delayed healing, or degenerative changes.
The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the vel... more The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm 2 . Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment.
AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognize... more AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. mAterIAl and methOds: After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes.
This study was designed to evaluate the possible protective effects of low-dose methotrexate in t... more This study was designed to evaluate the possible protective effects of low-dose methotrexate in the spinal cord injury (SCI) in rats.
Background: During cerebral ischemia reperfusion injury, oxidative stress leads to excitotoxicity... more Background: During cerebral ischemia reperfusion injury, oxidative stress leads to excitotoxicity, blood brain barrier dysfunction and inflammation. This study was designed to evaluate possible protective effects of low dose methotrexate on cerebral transient ischemia reperfusion injury in rat. Methods: Except CONTROL group, temporary aneurysm clips were performed to both common carotid arteries of rats for duration of 30 minutes. Four hours later, except CONTROL and SHAM groups, methotrexate (1.25 mg/kg/day) was administered intraperitoneally. Seventy two hours later, animals of CONTROL, MTX-A and SHAM-A group; and ten days later animals of MTX-C and SHAM-C group were sacrificed and hippocampal pyknotic neuronal cell count results and tissue lipid peroxidation (LPO) values were analyzed statistically. Results: Pyknotic cell count values of CONTROL group were lower than SHAM-A, SHAM-C, MTX-A and MTX-C group values. Cell count values of SHAM-A and MTX-A group were higher than SHAM-C and MTX-C values, respectively. LPO values of CONTROL group were lower than SHAM-A and MTX-A values, but not different from MTX-C and SHAM-C values. LPO values of MTX-A group higher than MTX-C group values. Conclusion: Cell count values and LPO values demonstrated that low dose methotrexate could not prevent neuronal cells from destructive effects of transient ischemia reperfusion injury in rat.
Objective: The object of this study is to describe a simple, rapid and cost effective method for ... more Objective: The object of this study is to describe a simple, rapid and cost effective method for purification of human leucocyte myeloperoxidase from a single donor. Myelopeoxidase (MPO) was purified by a two step procedure consisting of concanavalin-A Sepharose 4B affinity chromatography followed by CM-Sephadex cation exchange chromatography.
Comparative Biochemistry and Physiology Part C: Pharmacology, Toxicology and Endocrinology, 1999
Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with ... more Butyrylcholinesterase (BChE, EC 3.1.1.8) has been purified about 6600-fold from human serum with a procedure including ammonium sulfate fractionation (55-70%) with acid step at pH 4.5 and procainamide-Sepharose 4B affinity chromatography. The purified enzyme exhibited negative cooperativity with respect to butyrylthiocholine (BTCh) binding at pH 7.5. Ks was found to be 0.128 +/- 0.012 mM. Inhibition kinetics of the enzyme by Cd2+, Zn2+ and Al3+ were studied in detail. The 1/v vs 1/[BTCh] plots in the absence (control plot) and in the presence of different concentrations of cations intersected above 1/[BTCh]-axis. The data were analyzed by means of a nonlinear curve fitting program. The results demonstrated that all of the three cations are the linear mixed-type inhibitors of BChE. Ca2+ and Mg2+ had no effect on the enzyme activity in the experimental conditions. But when the enzyme was inhibited by 0.5 mM Cd2+ or Zn2+, Ca2+ and Mg2+ partially reactivated the inhibited allosteric form of BChE. Results were compared with data obtained from brain BChE purified from sheep.
Turkish Neurosurgery, 2012
AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognize... more AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. mAterIAl and methOds: After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes. results: There were statistically significant differences among the groups regarding the comparison of the values of the PMNL cell infiltration grades, gliosis and congestion in both acute and chronic stages. However, the values of the MNL cell infiltration grades, edema and fibrin formation, lipid peroxidation levels of harvested brain tissues were similar in all groups. COnClusIOn: Although this study did not present the detailed histopathological and biochemical evaluation results, it indicated that the application of the PEG-based hydrogel sealant was not associated with neurotoxicity, delayed healing, or degenerative changes.
The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the vel... more The aim of this study is to evaluate the effects of low-level laser therapy (LLLT) on (1) the velocity of orthodontic tooth movement and (2) the nitric oxide levels in gingival crevicular fluid (GCF) during orthodontic treatment. The sample consisted of 20 patients (14 girls, six boys) whose maxillary first premolars were extracted and canines distalized. A gallium-aluminum-arsenide (Ga-Al-As) diode laser was applied on the day 0, and the 3rd, 7th, 14th, 21st, and 28th days when the retraction of the maxillary lateral incisors was initiated. The right maxillary lateral incisors composed the study group (the laser group), whereas the left maxillary lateral incisors served as the control. The teeth in the laser group received a total of ten doses of laser application: five doses from the buccal and five doses from the palatal side (two cervical, one middle, two apical) with an output power of 20 mW and a dose of 0.71 J /cm 2 . Gingival crevicular fluid samples were obtained on the above-mentioned days, and the nitric oxide levels were analyzed. Bonferroni and repeated measures variant analysis tests were used for statistical analysis with the significance level set at p ≤ 0.05. The application of low-level laser therapy accelerated orthodontic tooth movement significantly; there were no statistically significant changes in the nitric oxide levels of the gingival crevicular fluid during orthodontic treatment.
AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognize... more AIm: Although polyethylene glycol (PEG) is a neutral, biocompatible hydrophilic polymer recognized for its lack of interaction with biological barrier, its neurotoxicity has not been clearly identified in neurosurgery. This study is constructed to evaluate the possible neurotoxicity of a PEG hydrogel dural sealant. mAterIAl and methOds: After a burrhole was opened in the left parietal bone of the twenty five Wistar albino rats, the dura mater and cerebral cortex were incised and the experimental material (activated polyethylene glycol and polyethylene imine) was sprayed into the burrhole. Then brain tissues were harvested for histopathological and biochemical studies at 72 hours to investigate the acute stage changes and on 15th day to evaluate the chronic stage changes.
This study was designed to evaluate the possible protective effects of low-dose methotrexate in t... more This study was designed to evaluate the possible protective effects of low-dose methotrexate in the spinal cord injury (SCI) in rats.
Background: During cerebral ischemia reperfusion injury, oxidative stress leads to excitotoxicity... more Background: During cerebral ischemia reperfusion injury, oxidative stress leads to excitotoxicity, blood brain barrier dysfunction and inflammation. This study was designed to evaluate possible protective effects of low dose methotrexate on cerebral transient ischemia reperfusion injury in rat. Methods: Except CONTROL group, temporary aneurysm clips were performed to both common carotid arteries of rats for duration of 30 minutes. Four hours later, except CONTROL and SHAM groups, methotrexate (1.25 mg/kg/day) was administered intraperitoneally. Seventy two hours later, animals of CONTROL, MTX-A and SHAM-A group; and ten days later animals of MTX-C and SHAM-C group were sacrificed and hippocampal pyknotic neuronal cell count results and tissue lipid peroxidation (LPO) values were analyzed statistically. Results: Pyknotic cell count values of CONTROL group were lower than SHAM-A, SHAM-C, MTX-A and MTX-C group values. Cell count values of SHAM-A and MTX-A group were higher than SHAM-C and MTX-C values, respectively. LPO values of CONTROL group were lower than SHAM-A and MTX-A values, but not different from MTX-C and SHAM-C values. LPO values of MTX-A group higher than MTX-C group values. Conclusion: Cell count values and LPO values demonstrated that low dose methotrexate could not prevent neuronal cells from destructive effects of transient ischemia reperfusion injury in rat.
Objective: The object of this study is to describe a simple, rapid and cost effective method for ... more Objective: The object of this study is to describe a simple, rapid and cost effective method for purification of human leucocyte myeloperoxidase from a single donor. Myelopeoxidase (MPO) was purified by a two step procedure consisting of concanavalin-A Sepharose 4B affinity chromatography followed by CM-Sephadex cation exchange chromatography.