A novel decision tree approach to predict the probability of conversion to multiple sclerosis in Iranian patients with optic neuritis.

BACKGROUND: assessing the risk of conversion to multiple sclerosis (MS) in patients with optic neuritis (ON) has been the topic of numerous studies. However, since the risk factors differ from population to population, the extension of conclusions is a matter of debate. This study focused on the Iranian patients with optic neuritis and assessed the probability of conversion to multiple sclerosis by using a machine-based learning decision tree. METHODS: in this retrospective, observational study the medical records of patients with optic neuritis from 2008 to 2018 were reviewed. Baseline vision, the treatment modality, magnetic resonance imaging (MRI) findings, and patients' demographics were gathered to evaluate the odds of each factor for conversion to MS. The decision tree was then obtained from these data based on their specificity and sensitivity to predict the probability of conversion to MS. RESULTS: the overall conversion rate to MS was 42.2% (117/277). 63.1 percent of patients had abnormal MRIs at baseline. The presence of white matter plaque had the highest odds for the conversion followed by the positive history of optic neuritis attack and gender. The regression tree showed that the presence of plaque was the most important predicting factor that increased the probability of conversion from 16 to 51 percent. CONCLUSION: the decision tree could predict the probability of conversion to MS by considering multiple risk factors with acceptable precision.

Role of S-methylisothiourea (SMT) in renal ischemia/reperfusion injury in rats.

INTRODUCTION: Excessive production of nitric oxide (NO) via inducible nitric oxide synthase (iNOS) is associated in renal ischemia reperfusion injury (IRI). OBJECTIVES: This study was designed to investigate the role of S-methylisothiourea (SMT) as selective inhibitor iNOS in renal IRI. MATERIALS AND METHODS: Male Wistar rats were subjected to 45 minutes of bilateral renal ischemia by occlusion of renal vessels of both kidney followed by 24 hours of reperfusion. Prior to renal IRI, the rats received either vehicle (saline, group 2) or SMT (50 mg/kg, group 3), and were compared with the sham-operated animals (group 1). At the end of reperfusion period, the rats were sacrificed for kidney tissue pathology investigation. RESULTS: Serum creatinine (Cr), blood urea nitrogen (BUN), nitrite levels, and kidney weight significantly increased in groups 2 and 3 (P < 0.05). Kidney tissue damage scores in groups 2 and 3 were also higher than that in the sham-operated group (P < 0.05). CONCLUSION: SMT not only prevent the kidney during IRI, but also promotes kidney function disturbance and severity of renal injury.