ABSTRACT
This work aimed at developing a natural compound-based hydrogel adsorbent to remove diclofenac as a model pharmaceutical from water. First, graphene oxide-chitosan (GO-CTS) and amine graphene oxide-chitosan (AGO-CTS) hydrogel adsorbents were synthesized via a facile mechanical mixing method. The synthesized materials were characterized through Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning and transmission electron microscopy (SEM and TEM), Raman spectroscopy, and thermogravimetric analysis (TGA) techniques. In the second stage, adsorption experiments were conducted to determine the best GO to CTS ratio and find the optimized adsorption parameters, including the initial drug concentration, adsorbent dosage, pH, and temperature. The results showed that the optimal GO to CTS mass ratio is 2 : 5 and thus the same ratio was selected as the AGO to CTS mass ratio to understand the effect of amine-functionalization on removal efficiency. The optimal adsorption parameters were determined to be pH of 5, C i of 100 ppm and dosage of 1.5 g L-1, where 90.42% and 97.06% removal was achieved for optimal GO-CTS and AGO-CTS hydrogel adsorbents, respectively. Langmuir and Freundlich isotherms models were employed to investigate the adsorption behavior of diclofenac onto the synthesized hydrogels. The results revealed that the adsorption tends to be of the monolayer type and homogeneous, as the results were in better accordance with the Langmuir model than the Freundlich model. The thermodynamics of adsorption demonstrated that the adsorption is exothermic, exhibiting higher removal efficiency at lower temperatures. Furthermore, Gibb's free energy change of adsorption (ΔG) suggested that the adsorption is spontaneous, being more spontaneous for AGO-CTS than GO-CTS hydrogels. Finally, the regeneration ability of the hydrogel adsorbents was studied in five consecutive cycles. The adsorbent maintained its efficiency at a relatively high level for three cycles but a considerable decrease was observed between the third and the fourth cycle, indicating that the hydrogels were recoverable for three cycles.
ABSTRACT
BACKGROUND: Urinary retention is a common postoperative complication that mandates urinary catheterization. Urinary catheterization is associated with different physical, mental, and financial problems for both patients and healthcare systems. The patient inconvenience, urinary tract infections, and increase in hospital stay and expenses are common problems of urinary retention and urinary catheterization. Therefore, alternative ways of relieving urinary retention, preferably noninvasive interventions, are of great interest. OBJECTIVES: The aim of this study was to compare the effects of placing hot pack and lukewarm-water-soaked gauze on the suprapubic region on male patients with postoperative urinary retention. PATIENTS AND METHODS: This was a three-group, randomized, controlled trial. A convenience sample of 126 male patients who had undergone general, orthopedic, or urologic surgeries were recruited. The block randomization method was used for allocating patients to either the two experimental groups (the hot pack and the lukewarm-water-soaked gauze groups) or the control one. Patients in the experimental groups were treated by placing either hot pack or lukewarm-water-soaked gauze on the suprapubic region. All patients were monitored for 20 minutes for urinary retention relief. If they did not experience urinary retention relief (starting urine flow and bladder evacuate), urinary catheterization would be performed. The data was collected using information sheet. Elimination of urinary retention was compared among study groups. The one-way analysis of variance and the Chi-square tests were used for analyzing data. RESULTS: Respectively, 59.5%, 71.4%, and 7.1% of patients in the hot pack, the soaked gauze, and the control groups experienced relief from urinary retention and the bladder was emptied. There was a significant difference among study groups in percentage of patients who experienced urinary retention relief. However, the difference between the two experimental groups was not significant. The time to urinary retention relief in hot pack, soaked gauze, and control groups was 15.45 ± 3.15, 13.83 ± 3.80, and 14.59 ± 3.29 minutes, respectively. The difference among the study groups in time to urinary retention relief was not statistically significant. CONCLUSIONS: Both the lukewarm-water-soaked gauze and the hot pack techniques had significant effects on postoperative urinary retention and significantly reduced the need for urinary catheterization. Using these two simple and cost-effective techniques for managing postoperative urinary retention is recommended.
ABSTRACT
OBJECTIVES: To report a novel approach to overcome the problems associated with a short right renal vein harvested by clipping the vein during right laparoscopic donor nephrectomy (RLDN). PATIENTS AND METHODS: This prospective study included 32 donors and their recipients; all donors had transperitoneal RLDN. The right renal artery and vein were ligated by Hem-o-lok and titanium clips, which resulted in a very short renal vein (<1.5 cm). When the kidney was positioned inverted in the recipient, the renal vein was placed posteriorly, adjacent to the external iliac vein, making a safe and simple venous anastomosis possible. RESULTS: All RLDN were completed with no conversion or re-operation. The mean (range) warm ischaemia time was 9.59 (3-17) min and there was no malfunction of the vascular clips on the major vessels. After a mean follow-up of 14 months the recipient survival rate was 97%. Graft function was excellent, with a mean (sd) serum creatinine level of 1.35 (0.31) mg/dL at 3 months after surgery, and there was no renal artery or vein thrombosis in any of the grafts. There were two ureteric complications (6%), i.e. one ureterocutaneous fistula resolved by secondary ureteroureterostomy, and one stricture at the site of ureteric anastomosis, which was managed by ureteroneocystostomy. CONCLUSION: The right renal vein obtained by LDN, after clipping the renal vein, is quite short, but by placing the kidney upside-down in the right iliac fossa transplantation is possible with no increased incidence of vascular thrombosis. This simple modification might obviate the need for removing a patch from the inferior vena cava, which is a challenging procedure for laparoscopic surgeons during RLDN.
