To study the olfactory function in rats by manganese-enhanced magnetic resonance imaging (MEMRI) and explore the regeneration of olfactory system from the imaging.Thirty-five adult male Sprague-Dawley (SD) rats were randomly divided into three groups. Twenty rats with bilateral nasal instillation of TritonX-100 were used as olfactory dysfunction model group (M group). The rats in this group received menthocamphorate stimulation. Ten rats with bilateral nasal instillation of sterile saline were used as olfactory normal group (N group), and were randomly divided into two groups:one group received menthocamphorate stimulation (N1 group), another group received odorless air (N2 group). The remaining five rats were used as the blank control (control group). All images were acquired with a 7.0 T micro-MR scanner. Signal-to-noise ratios (SNR) in the olfactory bulb (OB) were measured by Image J.MEMRI could clearly show the normal olfactory pathway in rats. MEMRI displayed a reversible change during the stages of olfactory recovery after injury. For the olfactory dysfunction model group (M group), the total volume of rat olfactory bulb at the initial, the 10th day, the 20th day, the 30th day and the 60th day were (49.44 ± 0.81), (32.85 ± 0.79), (27.78 ± 1.07), (35.89 ± 1.04), (43.63 ± 1.13) mm(3) respectively. At the 20th day after olfactory injury, the SNR in the OB was the lowest for 9.78 ± 0.07, when at the 60th day, the SNR recovered to 30.68 ± 1.01, which increased to near normal (N1group, 33.08 ± 0.15; N2 group, 31.31 ± 1.12), the SNR had no significant difference among the three groups (F = 3.04, P > 0.05).The MEMRI is an objective method to detect the olfactory function, and the olfactory system has the regenerative property after injury.
Objective: To describe satisfaction with the telehealth aspect of a pediatric obesity intervention among families from multiple rural communities and assess differences in satisfaction based on sociodemographic factors.
The objective of this study was to investigate the renal changes after intravenous administration of a high dose of either iodixanol or iopromide using functional magnetic resonance imaging (MRI) and computed tomography (CT).The study was approved by the institutional committee on animal research. Seventy-two male Sprague-Dawley rats were divided into 5 cohorts, comprising normal saline (NS), iopromide, iopromide + NS, iodixanol, and iodixanol + NS. Intravenous contrast was administrated at 8 g iodine/kg of body weight. Renal CT, quantitative functional MRI of blood-oxygen-level-dependent (BOLD) imaging and diffusion-weighted imaging (DWI), and histologic examinations were performed for 18 days after contrast administration. Statistical analysis was performed by using 1-way analysis of variance, Mann-Whitney test, and regression analysis.In the renal cortex, BOLD showed persistent elevation of R2* and DWI showed persistent suppression of apparent diffusion coefficient after iodixanol administration for 18 days. Compared with iopromide, adjusted ΔR2* (ΔR2*adj) was significantly higher in the iodixanol group from 1 hour to 18 days (P < 0.04) after contrast; adjusted ΔADC (ΔADCadj) was significantly more pronounced at day 6 (P = 0.01) after contrast. The iodixanol cohort also exhibited persistently higher attenuation in the renal cortex on CT and more severe microscopic renal cortical vacuolization up to 18 days. Intravenous hydration decreased the magnetic resonance changes in both groups but more markedly with iodixanol.At high doses, iodixanol induced greater changes in renal functional MRI (BOLD and DWI) relative to iopromide. Combined with longer contrast retention within the kidney, this suggests that iodixanol may produce more severe and longer-lasting contrast-induced renal damage.
Abstract Background : Rural children are more at risk for childhood obesity but may have difficulty participating in pediatric weight management clinical trials if in-person visits are required. Remote assessment of height and weight observed via videoconferencing may provide a solution by improving the accuracy of self-reported data. This study aims to validate a low-cost, scalable video-assisted protocol for remote height and weight measurements in children and caregivers. Methods: Families were provided with a low-cost digital scale and tape measure and a standardized protocol for remote measurements. Thirty-three caregiver and child (6-11 years old) dyads completed remote (at home) height and weight measurements while being observed via videoconferencing by research staff, as well as in-person measurements with research staff in the clinic. We compared the overall and absolute mean differences in child and caregiver weight, height, body mass index (BMI), and child BMI adjusted Z-score (BMIaz) between remote and in-person measurements using paired samples t-tests and one sample t-tests, respectively. Bland-Altman plots were used to estimate the limits of agreement (LOA) and assess systematic bias. Simple and multivariable regressions were used to examine whether sociodemographic factors and the number of days between measurements were associated with measurement discrepancies. Results : Overall mean differences in child and caregiver weight, height, BMI, and child BMIaz were not significantly different between remote and in-person measurements. LOAs were -2.1 and 1.7 kg for child weight, -5.2 and 4.0 cm for child height, -1.5 and 1.7 kg/m 2 for child BMI, -0.4 and 0.5 SD for child BMIaz, -3.0 and 2.8 kg for caregiver weight, -2.9 and 3.9 cm for caregiver height, and -2.1 and 1.6 kg/m 2 for caregiver BMI. Absolute mean differences were significantly different between the two approaches for all measurements. Child sociodemographic variables, caregiver education level, or time between measurements were not significantly associated with measurement discrepancies. Conclusions : Remotely observed weight and height measurements using non-research grade equipment may be a feasible and valid approach for pediatric clinical trials in rural communities. However, researchers should carefully evaluate their measurement precision requirements and intervention effect size to determine whether remote height and weight measurements suit their studies. Trial registration: ClinicalTrials.gov NCT04142034. Registered October 29, 2019