Tehran University Medical Journal

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Background: Umbilical cord blood gas analysis is a useful method for assessment of oxygenation and acid-base status in neonates. Severe fetal acidemia is associated with increased perinatal mortality and increased risk of subsequent impaired neurological development. Due to high percentage of C/S in our country and the effect of anesthetic medications on umbilical blood gases which can cause neonatal acidosis and hypoxemia, the study of umbilical cord blood gas in vaginal delivery versus cesarean section is mandatory.

Methods: In this cross-sectional study one hundred samples were taken from Mostafa Khomeini hospital in summer 2004. The samples were taken immediately of umbilical vein after clamping the umbilical cord and analyzed after 10 minutes. Cases were classified in to 3 groups: vaginal delivery (n=40), elective C/S under general anesthesia (n=35) and C/S under spinal anesthesia (n=25). Duration of anesthesia and its effect on blood gas and infants apgar were assessed.

Results: In the first group (vaginal delivery) mean blood gase parameters were pH=7.3064.73, pO2=25.246.87, HCO3=20.562.03, Apgar=8.820.38 and pCO2=41.826.57. In the second group (general anesthesia) mean blood gaze parameters were: pH=7.3044.73, pO2=38.7014.02, pCO2=43.265.87, HCO3=21.1113 and apgar score=8.170.7. In the third group (spinal anesthesia) mean blood gaze parameters were: pH=7.3014.50, pCO2=44.14.99, HCO3=21.382.15, pO2=26.625.5 and apgar=8.600.62. The apgar scores and pO2 demonstrated significant relationship with type of anesthesia. The apgar score was lower and pO2 was higher in C/S under general anesthesia compared with the other two groups. There was significant relationship between duration of anesthesia and umbilical pO With increasing duration of anesthesia, pO2 was reduced. Between the type of delivery and anesthesia duration with PH, pO2, pCO2 and HCO3 were not meaningful relationship (P<0.05).

Conclusion: There was no significant difference between type of delivery and umbilical blood gas parameters. Neonatal apgar score in NVD is higher than the other groups. With increasing duration of general anesthesia in C/S, umbilical po2 is reduced.

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Background: Previous studies have suggested the presence of a relationship between the increase of NRBC and the duration and intensity of asphyxia. The purpose of this study was to evaluate the relationship of fetal heart rate pattern and the number of NRBC's in umbilical cord blood sample at birth.

Methods: We enrolled 322 pregnant women with healthy, term fetuses who referred to Mirza Kouchak Khan Hospital for pregnancy termination in 2005 in a case-control study. All patients underwent continuous FHR monitoring and based on their FHR pattern, they were divided into two groups with normal FHR pattern and at least one abnormality in FHR pattern (including absence of beat to beat variability absence of proper acceleration and early, late, variable and prolonged deceleration). Samples of umbilical cord blood were evaluated for NRBC count and pH immediately after birth. The variables were compared in these two groups.

Results: The mean NRBC count was significantly higher in patients with any kind of deceleration (late, variable, early or prolonged) in comparison with controls (respectively 11.88±4.406, 8.32±4.64, 10.58±5.366, and 4.11±4.913 vs. 0.93±1.790 in controls). Furthermore the mean NRBC count was significantly higher in patients with absence of acceleration or beat to beat variability (10.73±5.07 and 13.73±3.58 vs. 1.47±2.50). There was a negative correlation between 5^th minute Apgar score and umbilical cord blood sample with mean NRBC count of umbilical cord blood sample.

Conclusion: Any abnormality in FHR pattern is associated with a significant increase in mean NRBC count of umbilical cord blood sample. There is also a significant relationship between the 5^th minute Apgar score and umbilical cord blood sample pH, and mean NRBC count in umbilical cord blood sample.

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Background: Hematopoietic stem cell transplantation (HSCT) is a therapeutic approach in treatment of hematologic malignancies and incompatibility of bone marrow. Umbilical cord blood (UCB) known as an alternative for hematopoietic stem/ progenitor cells (HPSC) for in allogenic transplantation. The main hindrance in application of HPSC derived from umbilical cord blood is the low volume of collected samples. So, ex vivo expansion of HPSCs is the useful approach to overcome this restriction. Synthetic biomaterials such as nanofibers is used to produce synthetic niches. The aim of this study was the ex vivo expansion of hematopoietic stem cells on biocompatible nanofiber scaffolds. Methods: This study was done at Tarbiat Modares University from November 2012 to June 2013 and was a research study. Umbilical cord blood CD133+ hematopoietic stem cells were separated using MidiMacs (positive selection) system by means of monocolonal antibody (microbeads) CD133. Flow cytometry was used to assess the purity of cells. Cell culture was done on plate (2 Dimensional) and fibronectin conjougated polyether sulfone nanofiber scaffold (3 Dimensional). Colony assay test was used to asses the ability of colonization of cells. Results: Cell count analysis revealed the expansion of hematopoietic stem cells in cell culture plate (2D environment) and on nanofiber scaffold (3D environment) after 2 weeks. Expansion of cells in 2D environment was greater than 3D condition. Colony assay test revealed that the colonization ability of cells decreased after 2 weeks, but this decrease was lower in scaffold culture than plate culture. Conclusion: This study demonstrated that umbilical cord blood CD133+ hematopoietic stem cells can expand on fibronectin conjugated polyether sulfone scaffold and we can use this system for expanding of cells in vitro situation.