Prevalence of HBV, HCV, and HIV Infections among Patients Undergoing Hemodialysis in Fasa, Iran: A Six-Year Follow-up Study

Background: Hemodialysis (HD) patients are at risk of viral infections such as hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency viruses (HIV). Current study aimed to determine the prevalence of HBV, HCV, and HIV among HD patients who attended the dialysis center in Fasa, Iran. Methods: Collectively, 2082 HD patients (1291 men, 791 women) took part in our 6-year follow-up study. Results: 2082 HD patients with a mean age of 56.2±17.8 were included in our study. One (0.09%) patient was HBsAg positive, two (0.18%) patients were anti-HCV positive, and one (0.09%) was anti-HIV positive. There was no significant correlation between the paraclinical parameters of men and women. Conclusion: The present study showed a reduction in the prevalence of HBV, HCV, and HIV infections during 6 years of follow-up in HD patients.

On using experimentally estimated wall shear stresses to validate numerically predicted results

The objective of this investigation was to assess the use of experimentally estimated wall shear stresses to validate numerically predicted results. The most commonly cited haemodynamic factor implicated in the disease initiation and proliferation processes at graft/artery junctions is wall shear stress (WSS). WSS can be determined from the product of the viscosity of the fluid and the wall shear rate. Numerically, the wall shear rate is predicted using velocity values stored in the computational cell near the wall and assuming zero velocity at the wall. Experimentally, the wall shear rate is estimated by applying a curve-fit to near-wall velocity measurements and evaluating the shear rate at a specific distance from the wall. When estimating the wall shear rate from the laser Doppler anemometry (LDA) point velocity measurements, large differences between the experimentally estimated and numerically predicted WSSs were introduced. It was found that the estimated WSS distributions from the experimental results are highly dependent on the curve-fitting method used to calculate the wall shear rate. However, the velocity profiles for both the experimental and numerical investigations show extremely good comparison. It is concluded that numerical models should be validated using unprocessed LDA point velocity measurement and not estimated WSS values.