Study of Co[II] adsorption from aqueous solution using protein granules produced from chicken feather

Background: Co[II] constitutes a part of vitamin B12, hence, it is necessary for human health. However, at concentrations higher than the permissible limits, humans and animals suffer adverse chronic effects. It is necessary to reduce the concentration to a permissible level. In the present study, pre-purification and thermal modification of chicken's feather increased their porosity and they were used to adsorb Co[II] ions from aqueous solutions

Methods: Chicken feather was procured from a slaughter house, washed with detergent and dried at laboratory temperature. To increase the porosity and remove the organic pollutants attached to the feather, feathers were heated in the oven for 1 hour at 165 degree C. Some batch experiments were conducted to optimize the parameters affecting the adsorption process, such as solution pH, initial concentration of Co[II] and contact time, at a constant agitating speed and temperature

Results: The pH[zpc] of chicken's feather granules obtained was 5.3. The results showed that a time of 60 minutes, pH value of 9 and initial concentration of 10 mg/l were the optimum conditions for Co[II] removal by the adsorption process. Increasing the initial concentration of Co[II] from 10 to 50 decreased the removal efficiency from 52% to 26%. The pseudo-first order kinetic model provided the best correlation [R[2] = 0.998] for adsorption of Co[II] on chicken's feather granules

Conclusion: The increase in electrostatic repulsion forces between positive charges of Co[II] ions decreased the removal efficiency at higher concentrations of Co[II] ions. The maximum efficiency of Co[II] adsorption was obtained at pH= 9, which is higher than the pH[zpc] of the adsorbent

Evaluations of topical application of tranexamic acid on post-operative blood loss in off-pump coronary artery bypass surgery

One of the major complications of cardiac surgery is the presence of post-operative bleeding. The aim of the present study was to investigate the topical application of tranexamic acid in the pericardial cavity on post-operative bleeding in off-pump coronary artery bypass graft [CABG] surgery. This study was on 71 patients who underwent off-pump CABG. The anesthesia and surgery methods were the same for all patients. Patients were assigned to two equal groups. In the first group, 1 g of tranexamic acid in 100 mL of normal saline solution [NSS] was applied to pericardium and mediastinal cavity at the end of surgery. In the second group, only 100 mL of NSS was applied. Chest drainage of the patients after 24 h and the amounts of blood and blood products transfusion were also recorded during this time. Patients were the same regarding demographic information and surgery. The average volume of blood loss after 24 h was 366 mL for the first group and 788 mL for the control group. There was a statistically significant difference between the two groups [P < 0.001]. The amount of packed red blood cells transfusion in the first group was less than that of the control group, which was not statistically significant. There was no statistically significant difference between the amount of hemoglobin, hematocrit, platelets, prothrombin time and partial thromboplastin time in the postoperative stage in the two groups. The topical application of tranexamic acid in off-pump CABG patients leads to a decreased post-operative blood loss.

effect of ondansetron and meperedin on preventing shivering after off-pump coronary artery bypass graft

One of the most common complications of operation and anesthesia is shivering. The purpose of this study was to compare the effectiveness of Ondanseton and Meperedine in preventing shivering after off pump coronary artery bypass graft [OPCAB]. In this double-blind randomized clinical trial, the sample consisted of 90 patients, who were candidates of CABG under general anesthesia. These patients were assigned to three groups, each containing 30 subjects: meperedine group [A], ondansetron group [B] and control group [C]. Group [A] received 0.4 mg/Kg/IV of meperedine, group [B] received 8mg/IV of ondansetron and group [C] received Normal Saline. All these drugs were injected 15 minutes before the end of surgery. After the end of surgery, the intubated patients were transferred to the ICU and their body temperature was assessed through eardrum by a specialist who was blind to the research. The incidence of shivering in groups A, B, and C was 46.48%, 31.18%, and 60.83%, respectively [P=<0.01]. The incidence of shivering was 64.4% in males and 35.6% in females [P=0.222]. Also, the amount of incidence of shivering up to 3 hours after surgery was 75.87% [P=0.064]. Bradycardia was 3.3% in group [A] and 0.0% in group [B]. Other variables [myoclonus, seizure and rash] showed no statistically significant difference [P=0.353]. According to the findings, it was demonstrated that ondansetron is more effective in preventing shivering after Off-pump CABG than meperedine