Biomedical properties and hemostatic efficacy of polyvinyl alcohol (PVA) based hydrogel in experimental rat liver injury model.

PURPOSE: Bleeding is a leading cause of mortality and morbidity in the trauma and surgery field, using effective hemostatic agents can help us reduce bleeding especially in parenchymal hemorrhage. Nowadays polyvinyl alcohol (PVA) is known as a safe candidate for wound dressing and maybe a hemostatic agent. PVA-based hydrogel is a popular biocompatible material in the biomedical field especially when it has high water absorption. In this study, we investigated the PVA hydrogel's mechanical and biological properties as well as its hemostatic potential in parenchymal bleeding. METHODS: PVA hydrogel had made by the freeze-thawing approach, we used PVA hydrogel in comparison to standard treatment to investigate hemostatic potency. Also, we performed MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) tests to survey PVA cellular toxicity. After an acute liver injury, two groups of 12 rats were treated with PVA hydrogel or standard treatment with sterile gauze. The results including the time and volume of bleeding, and the time and survival rate of the rats were measured and compared. RESULTS: We saw that PVA hydrogel was safe with no cellular toxicity in the MTT assay. Regarding efficacy, PVA hydrogel increased rats' survival after bleeding from 75% to 91.7%, and decreased bleeding time (p: 0.015), and bleeding volume (p: 0.03) compared to the control group. CONCLUSION: Polyvinyl alcohol is safe. It has good biological properties with no cellular toxicity and has a significant hemostatic effect and can be regarded in control of parenchymal hemorrhage.

Surgical management of retrorectal tumors: a single-center 12 years' experience.

Purpose: Retrorectal tumors (RTs) are rare tumors that arise in the space between the mesorectum and the pelvic wall and often originate in embryonic tissues. The primary treatment for these tumors is complete excision surgery, and choosing the best surgical approach is very important. Methods: In this study, we retrospectively collected the data of 15 patients with RTs who underwent surgery in the surgical ward of Imam Khomeini Hospital in Tehran for 12 years to share our experiences of patients' treatment and compare different surgical approaches. Results: A total of 5 tumors were malignant, 10 were benign, and most of the tumors were congenital. Malignant tumors were seen in older patients. Three surgical procedures were performed on patients. Three patients underwent abdominal approach surgery, and 8 patients underwent posterior surgery. A combined surgical approach was performed on 4 patients. Two patients underwent laparoscopic surgery. The abdominal approach had the least long-term complication, and the combined approach had the most complications; laparoscopic surgery reduced the length of hospital stay and complications after surgery. Conclusion: A multidisciplinary team collaboration using magnetic resonance imaging details is necessary to determine a surgical treatment approach. It could reduce the need for a preoperative biopsy. However, every approach has its advantages and disadvantages. In the main, they have no superiority over each other, and individualized treatment is the key.

Which Metabolic Index is Appropriate for Predicting Non-alcoholic Steatohepatitis?

BACKGROUND There are controversial ideas about the application of metabolic indices for the prediction of nonalcoholic steatohepatitis (NASH). In this study, we evaluated some novel metabolic indices for the screening of NASH. METHODS This prospective case-control study was performed in a gastroenterology outpatient clinic. Consecutively selected patients with persistently elevated aminotransferase levels and evidence of fatty liver in ultrasonography were enrolled. Those with other etiologies of aminotransferase elevation were excluded. The remaining was presumed to have NASH. The control group consisted of age and sex-matched subjects with normal liver function tests and liver ultrasound examinations. RESULTS Finally, 94 patients with steatohepatitis and 106 controls were included in the project. The mean liver fat content (LFC), aspartate aminotransferase, and alanine aminotransferase levels were significantly lower in the control group than in the NASH group. LFC was independently associated with the presence of NASH in logistic regression analysis. LFC had a good area under the curve for the prediction of NASH in ROC (receiver operating characteristic curve) analysis. CONCLUSION LFC seems to be a reliable metabolic index for the detection of patients with NASH.