Razi Journal of Medical Sciences

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ABSTRACT The purpose of this study was to compare the resistance of propiobacteriom acne (PA) and staphylococcus epidermis(SE) to antibiotics in patients that have been treated with antibiotics, With those cases without previous history of therapy as the control group. 60 patients were included in this study. At the time of sampling, all 30 cases of study group had been on therapy for a minimum of 4 months on oral tetracycline and topical clindamycin and erythromycin 30 patients were included in the control group without previous history of antibiotic therapy. Mic (Minimum Inhibitory Concentration) was performed on PA or SE isolated from skin surface of these cases. Erythromycin resistant PA and SE isolated from antibiotic treated acne patients was 43.3% (P=0.024). Tetracycline resistant PA and SE isolated from study group was 40% (P<0.0001). Clindamycin resistant PA and SE isolated from study group was 43.3%(P=0.004). Results of this study show that, incidence of resistance to antibiotics in patients undergoing antibiotic therapy for acne was higher than control group, and there is a correlation between the resistance of SE and PA and the former therapy for acne.

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    Introduction: Pancreatitis is uncommon in children. The incidence is higher in chronic renal failure, hemodialysis, and chronic ambulatory peritoneal dialysis(CAPD) patients and accompanied with late complications including pancreatic necrosis, pseudocyst and abscess. Case Report: We report a 5 year old girl with end stage renal disease due to focal segmental glomerulosclerosis, being on CAPD for two years. She was admitted for intermittent severe epigastric pain of four months duration, hypotension, severe cachexia and cloudy drained dialysate with negative culture and mild increment serum amylase. On abdominal imaging a pancreatic cyst was reported which was an infected cyst on laparotomy. Despite drainage of suppurative fluid and antibiotic therapy, the patient expired with severe sepsis and multiorgan dysfunction two weeks after operation. Conclusion: The presence of poor weight gain, unexplained abdominal pain and cloudy drained dialysate in children on CAPD may suggest pancreatitis. Frequent evaluation of pancreatic function and sonography is recommended.

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  Background & Aim: Cyclosporine-A (CsA) is an immunosuppressant with a narrow therapeutic window. Inter-and-intrapatient variability in cyclosporine pharmacokinetics necessitates frequent blood level monitoring in transplant patients and total blood cyclosporine concentration used to allow dosage adjustment in transplant patients. The purpose of the present study was, first of all, to develop a precise and suitable method for therapeutic drug monitoring (TDM) of cyclosporine in children with renal transplant and to evaluate CsA blood concentrations in patients in order to find out the best time for sampling Iranian children with kidney transplant for TDM of cyclosporine. This can also help us achieve the best immunosuppressant with the least side effects for renal transplant patients.

  Patients and Method: In this experimental study, 29 pediatric transplant recipients (16 boys and 13 girls) who had received renal transplant at least six months prior to the study participated. The mean age of the patients was 14. 5 ±2. 3 years (ranging from 8 to 20 years),and they all showed stable renal function. The patients were also receiving other drugs such as prednisolone, mycophenolate mofetil, iron and folic acid. The clinical status of the patients was recorded. The CsA blood levels were determined using radioimmunoassay (RIA) 0, 0. 5, 1, 1. 5 and 2 hours after drug administration. The data analysis was performed using Pearson correlation coefficient.

  Results: Our results are indicative of good precision and�reproducibility of the method. Minimum detection limit of cyclosporine-A was 5 ng/ml and percentage yield was 86-109%. Inter-and-intraday variability for three cyclosporine-A blood concentrations were 8% and 5. 8% respectively. The mean blood concentrations 0. 5 and 1 hour after drug administration were 100 ± 3. 0 and 515± 19. 2 μ g/dl respectively. The mean serum creatinine level was 0. 9 (0. 1-1. 9) mg/dl. There was a high correlation between CsA dose, serum creatinin and C_{1. 5}, while there was no correlation between age, serum creatinine and C_{1. 5} level. Also, there was no correlation between C₀ and any of the above-mentioned parameters. These results show that C_{1. 5} level is the best indicator for TDM of cyclosporine-A in Iranian children and has the best correlation with dose and creatinin level.

  Conclusion: The developed method is precise,sensitive and suitable for therapeutic drug monitoring of cyclosporine-A. Using single point monitoring can help to improve the cooperation of patients during TDM procedure, and for this purpose C_{1. 5} level seems more accurate than C₀ level in pediatric transplant patients.

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Background & Aims: The considerable growth of 3D printing technology in recent years has led to the application of this emerging technology in many medical fields, in which recently performed studies have shown the special importance of this technology which can enhance the results of the treatment method. Since, surgery is one of the main modalities to treat patients, the advent of 3D printing technology in surgery and the creation of different patient organs with 3D printers, improve the surgeon's performance. Hence, the accuracy and quality of the surgery can be enhanced. The aim of this study was to review the current statues and the applications of the 3D printing technology in surgery.
Methods: By searching the indexed articles in Persian and Latin databases, Scopus, PubMed, Science direct, Scholar, 34 studies were reviewed.
Results: 3D printing applications in surgery: Generally, the ability to generate a physical object with complex structures from a digital model has been introduced as the 3D printing technology which offers many advantages over the traditional manufacturing. The most important advantage of 3D printing technology is the ability to produce objects based on individual needs in which can reduce the costs of their production. Furthermore, complex preoperative procedures can be practiced. In other words, 3D printed models allow physicians to become familiar with medical procedures which possible problems created during the operation, can be identified before the operation. This modern technology generally includes three main steps to generate 3D objects from imaging data. The first step is the acquisition of image data. Then, the interest region is extracted which is termed as the segmentation. Finally, the digital data is transferred to the 3D printers to produce the 3D object.  For 3D model production, printer selection highly depends on speed, accuracy, cost, and availability of the printing materials. Recent advances in 3D printing technology have made it possible to use various biocompatible materials such as titanium and degradable polyesters to produce 3D models.
Complex surgeries require more precise visual understanding before the surgery to ensure about the success of the treatment. In this regard, 3D printing technology can be a promising way to produce faster and cheaper models. In addition, this modern technology enables producers to produce highly specialized products for a wide range of patient organs. Applying a physical model results in better performance and greater visual perception about the desired treatment area, which can significantly reduce the side effects during surgery. Since a large contribution of the surgical process can be performed outside the operating room hence, 3D printed models can reduce the operation time. In fact, before the operation, surgeons will have enough time to make decisions, evaluate solutions and focus on other key elements during the operation. So, based on the basic role of 3D printing technology in surgery, the purpose of the present review is to investigate the current state of 3D printing technology and its clinical application in surgery for the construction of various 3D organs via medical imaging data. In this paper, some applications such as maxillofacial, spinal, liver, etc., are briefly discussed.
Maxilla-facial and cranial facial reconstruction are the complex procedure which have been one of the first and most proven applications of 3D printing in the field of surgery to correct the facial deformities after the tumor resection. In this method with the application of 3D printers, at first, a 3D model of the desired anatomy is prepared to reduce a significant amount of time for linking the titanium plates to transplant adjacent bones (while the patient is anesthetized). Also, the production of titanium implants using the 3D printers will result in a very precise fit with the target tissue, the risks of maxillofacial surgery can be reduced.
The use of 3D printing applications before or during complex surgeries like congenital heart defects has been reported in several studies. Since, acquiring to the real anatomical structures in patients with complex congenital defects, are sometimes unpredictable, treatment planning and surgical decision-making require a thorough understanding of three-dimensional anatomy. Therefore, the 3D printing technique, as a widely used method in all medical fields can overcome the defects of common preoperative imaging, especially in cardiovascular surgery.
The other application of 3D printing technology includes spinal surgery in which due to the complex anatomy of the spine and the delicate nature of the surrounding structures, 3D printers will improve preoperative planning and increase the accuracy during the surgery.
Liver surgery can be another suitable candidate for performing 3D printing technology to create 3D printing models. The two main applications of 3D printing technology in this field include training or necessary planning for surgery and liver functional cell printing through bio-printing technology that can be used in the study of liver disease and pharmaceutical research.
Renal tumor resection is the other example of 3D printing applications in which 3D models have an exclusive role to enhance the accuracy of renal surgery. The 3D printed models can accurately display three-dimensional spatial relationships between different anatomical and pathological structures. Three-dimensional printed kidney models may also facilitate interdisciplinary communication and decision-making about the management of patients undergoing renal surgery.  In the field of renal surgeries, employing of 3D printed models plays a specific performance to train young surgeons which consequently increases the practical skills of surgeons which can accurately visualize the anatomical and morphological relationship compared to volumetric imaging.
The obtained results of performed studies in the field of 3D printing show the potential significance of this technology in surgery which can lead to improvement of therapeutic outcomes. Since the printed models by 3D printing technology have an appropriate fit to the anatomy, the use of these models can reduce the associated errors during surgery.
It is worth noting that despite the valuable advantages of this technology, some disadvantages such as limited printing size and costly printing process can be discussed which many studies try to address the deficiency of 3D printing technology in clinical applications. The cost of 3D printed models varies according to the type of performed printing method and applicable software which requires specialized users. The main mentioned costs for 3D model creation include hardware, software, and printed materials. In the future, the production costs of 3D models would be likely reduced in which the use of 3D models would become more traditional in common clinical operation. The 3D printed physical models are based on medical imaging which are prone to errors during the imaging procedures. Hence, increasing the accuracy of creating printed models requires improving the clinical imaging methods. Generally, with the advances in this modern technology, faster, cheaper, and more accurate models can be produced.

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