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Newly created arteriovenous fistulas (AVFs) often fail to mature for dialysis use due to disturbed blood flow at and near the AVF anastomosis. The disturbed flow inhibits the endothelial nitric oxide synthase (NOS3) pathway, thus decreasing the production of nitric oxide, a vasodilator. Previously, our group reported that NOS3 expression levels affect AVF lumen size in a mouse model. In this study, we performed MRI-based computational fluid dynamics simulations to investigate the hemodynamical parameters (velocity, wall shear stress (WSS), and vorticity) in a mouse AVF model at day 7 and day 21 post-AVF creation using three NOS3 strains: overexpression (OE), knockout (KO), and wild-type (WT) control. This study is the first to reveal hemodynamics over time in mouse AVFs, consider spatial heterogeneity along the vein, and reveal the effect of NOS3 on the natural history of mouse AVF hemodynamics. From day 7 to day 21, OE has smoother streamlines and had significantly lower vorticity and WSS than WT and KO, suggesting that WSS was attempting to return to pre-surgery baseline, respectively. Our results conclude that the overexpression of NOS3 leads to desired optimal hemodynamics during AVF remodeling. Future studies can investigate enhancing the NOS3 pathway to improve AVF development., (© 2023. The Author(s).)

Background: Arteriovenous fistula (AVF) creation may negatively affect cardiac structure and function and impact cardiovascular mortality. The objective of this study was to develop and characterize the cardiac changes following AVF creation in a murine AVF model., Methods: AVFs were constructed using the carotid artery and jugular vein in C57BL/6 mice. Sham-operated AVF mice served as the control group. 2D-echocardiography was performed prior to AVF creation (baseline) and at 7 and 21 days after creation in AVF and sham-operated mice. Picrosirius red was used to stain the left ventricle for collagen production., Results: The cardiac output (CO), left ventricular end diastolic (LVEDD) and systolic (LVESD) diameter, and end-diastolic (LVEDV) and systolic (LVESV) volume was significantly increased at 7 and 21 days in AVF compared to sham-operated mice. There was also a significant increase in CO, LVEDD, LVESD, LVEDV, and LVESV from baseline to 21 days within the AVF group, but not the sham-operated mice. There was a significant decrease in ejection fraction and fractional shortening at 21 days in AVF compared to sham-operated mice. Picrosirius red was significantly more prominent around both the perivascular and interstitial areas of the cardiac tissue from AVF mice compared to sham-operated AVF mice at 21 days., Conclusions: The creation of an AVF in our murine model leads to cardiac changes such as increased cardiac output, left ventricular dilation, and cardiac fibrosis, while showing reductions of ejection fraction and fractional shortening.

Objective: This study aimed to determine the prevalence of PPPD in Anuradhapura district, its association with maternal PPD, and relevant risk factors., Materials and Methods: Cross sectional study was conducted among fathers in Anuradhapura district having infants 1-5 months by giving questionnaire specifically developed for the study with Edinburgh postnatal depression scale (EPDS) and self-constructed questions. Out of 6324 fathers, 435 fathers and their partners were randomly selected and proportionately allocated to 5 Medical Officer of Health (MOH) areas. R Program and SPSS have used for the data analysis., Results: Our results revealed that the PPPD prevalence is approximately 11% (95%CI: 8.08-14.67) based on cut off score of 7 points in the EPDS. PPPD was correlated with maternal PPD (OR 19.16, 95%CI 5.0473-85.1203), income decrement (OR 8.1571, 95%CI 2.4621-32.6289), increased time stayed at home in postpartum period (OR 3.7775, 95%CI 1.2365-13.8175). But other parameters such as infant's age, work time and number of children were not significantly influenced risk factors for PPPD., Conclusion: PPPD is prevalent in the Anuradhapura district and maternal postpartum depression has positively influenced. But currently, screening programmes for PPPD is lacking in Sri Lanka. Thus, these deficiencies urgently need to be addressed and should provide information and instructions to fathers regarding this new transition. However, these results need replication in more expanded case control study. Since the prevailing covid-19 pandemic at the time of data collection may have impacted the mental health of the fathers specially in countries like Sri Lanka, where mental health support is limited., Competing Interests: Conflict of Interests Authors have no conflict of interests., (Copyright © 2022 Tehran University of Medical Sciences. Published by Tehran University of Medical Sciences.)