Joint modeling of longitudinal and competing risks for assessing blood oxygen saturation and its association with survival outcomes in COVID-19 patients.

BACKGROUND: The objective of the present study is to evaluate the association between longitudinal and survival outcomes in the presence of competing risk events. To illustrate the application of joint modeling in clinical research, we assessed the blood oxygen saturation (SPO2) and its association with survival outcomes in coronavirus disease (COVID-19). MATERIALS AND METHODS: In this prospective cohort study, we followed 300 COVID-19 patients, who were diagnosed with severe COVID-19 in the Rohani Hospital in Babol, the north of Iran from October 22, 2020 to March 5, 2021, where death was the event of interest, surviving was the competing risk event and SPO2 was the longitudinal outcome. Joint modeling analyses were compared to separate analyses for these data. RESULT: The estimation of the association parameter in the joint modeling verified the association between longitudinal outcome SPO2 with survival outcome of death (Hazard Ratio (HR) = 0.33, P = 0.001) and the competing risk outcome of surviving (HR = 4.18, P < 0.001). Based on the joint modeling, longitudinal outcome (SPO2) decreased in hypertension patients (ß = -0.28, P = 0.581) and increased in those with a high level of SPO2 on admission (ß = 0.75, P = 0.03). Also, in the survival submodel in the joint model, the risk of death survival outcome increased in patients with diabetes comorbidity (HR = 4.38, P = 0.026). CONCLUSION: The association between longitudinal measurements of SPO2 and survival outcomes of COVID-19 confirms that SPO2 is an important indicator in this disease. Thus, the application of this joint model can provide useful clinical evidence in the different areas of medical sciences.

Assessment of the Neuroprotective Effects of Lavandula angustifolia Extract on the Contusive Model of Spinal Cord Injury in Wistar Rats.

INTRODUCTION: Spinal cord injury (SCI) involves a primary trauma and secondary cellular processes that can lead to severe damage to the nervous system, resulting in long-term spinal deficits. At the cellular level, SCI causes astrogliosis, of which glial fibrillary acidic protein (GFAP) is a major index. OBJECTIVE: The aim of this study was to investigate the neuroprotective effects of Lavandula angustifolia (Lav) on the repair of spinal cord injuries in Wistar rats. MATERIALS AND METHODS: Forty-five female rats were randomly divided into six groups of seven rats each: the intact, sham, control (SCI), Lav 100, Lav 200, and Lav 400 groups. Every week after SCI onset, all animals were evaluated for behavior outcomes by the Basso, Beattie, and Bresnahan (BBB) score. H&E staining was performed to examine the lesions post-injury. GFAP expression was assessed for astrogliosis. Somatosensory evoked potential (SEP) testing was performed to detect the recovery of neural conduction. RESULTS: BBB scores were significantly increased and delayed responses on sensory tests were significantly decreased in the Lav 200 and Lav 400 groups compared to the control group. The greatest decrease of GFAP was evident in the Lav 200 and Lav 400 groups. EMG results showed significant improvement in the hindlimbs in the Lav 200 and Lav 400 groups compared to the control group. Cavity areas significantly decreased and the number of ventral motor neurons significantly increased in the Lav 200 and Lav 400 groups. CONCLUSION: Lav at doses of 200 and 400 mg/kg can promote structural and functional recovery after SCI. The neuroprotective effects of L. angustifolia can lead to improvement in the contusive model of SCI in Wistar rats.

Bladder mucosal autograft: An effective method for repair of vesicovaginal fistula.

BACKGROUND: To investigate the effectiveness of bladder mucosal autograft for the treatment of vesicovaginal fistulae. MATERIALS AND METHODS: Between March 2005 and June 2011, 21 patients with a single vesicovaginal fistula above the trigone, not involving the ureters, underwent surgery. Bladder was approached extraperitoneally and opened in the midline. The mucosa around the fistula was incised and inverting sutures were placed over the fistula opening. The mucosal defect was covered by a free mucosal graft from the edge of cystotomy incision. RESULTS: After catheter removal at 2 weeks, 18 patients (85 %) remained dry while one patient experienced urge incontinence, which resolved in a few days and another one still had urine leakage (although less than before the operation) that improved after another 3 weeks of bladder drainage. Only in one patient, the operation failed. CONCLUSION: Short duration of hospitalization, simplicity of the procedure, avoidance of extensive bladder dissection, and extraperitoneal nature of the operation, along with a high success rate are the advantages of this procedure. This technique could be recommended for single fistulae not involving the ureters and not secondary to malignancies.

Efficacy of terazosin as a facilitator agent for expulsion of the lower ureteral stones.

OBJECTIVE: To determine the efficacy of terazosin as a facilitator agent for the passage of lower ureteral stones. METHODS: Since February 2004 to December 2004, 64 patients with lower ureteral stones who came to the emergency department were enrolled in this study. Exclusion criteria were the presence of urinary tract infection, severe hydronephrosis, elevated serum creatinine, hypertension, history of peptic ulcer disease and history of spontaneous stone passage. Patients were randomized into 2 groups of 32. Group 1 patients received terazosin tablets, 10 mg daily and analgesic (indomethacin capsules) for a maximum of 4 weeks, but patients in Group 2 received only analgesic. In cases of incomplete pain control, intravenous pethidine was administered. The 2 groups were compared with regard to stone passage rate, time to stone passage, the amount of received pethidine and the need for intervention. Statistical analysis was performed by student t-test. RESULTS: The mean age of Group 1 was 44 years and Group 2 was 39 years. The median stone size was 6.9 +/- 2.3 mm in Group 1 and 6.6 +/- 3.1 mm in Group 2, which was not significantly different. Stone expulsion rate was 90.62% in Group 1 and 62.5% in Group 2, with a significant statistical difference (p=0.041). The mean expulsion time was 76.3 +/- 60 hours and 141 +/- 64 hours in Groups 1 and 2, (p=0.001). Extra analgesic (pethidine) requirement averaged 34.4 +/- 12.7 mg and 62.1 +/- 10.5 mg in Groups 1 and 2 (p=0.036). Seven patients in Group 1 and 15 patients in Group 2 required ureteroscopy after 4 weeks due to lack of the stone passage. CONCLUSION: Terazosin is a safe and effective treatment for lower ureteral stones. By using this medication, stone passage rate increases and the time of stone passage and the need for intervention decreases.