Sampling of umbilical cord blood gases after operative deliveries.

Assessment of the umbilical cord gases at birth is an objective measurement of the neonatal condition. However, previous studies have shown that the results are unreliable in one out of four paired samples. The aim of our study was to assess the sampling of cord gases after operative deliveries. We found out that the error rate in our unit was 39% and the erroneous sampling was more common in arterial samples and in deliveries that happened during the night. We believe that assessment of the results obtained from paracentesis of the umbilical vessels helps to evaluate the quality of the sampling and to identify preventable causes of error.     

选择性剖宫产对新生儿脐血纤溶酶活性及免疫因子的影响

目的探讨选择性剖宫产对新生儿脐动脉血纤溶酶活性,血清免疫球蛋白和补体含量的影响。方法中国医科大学附属二院于2001年1月至2004年10月分别采用发色底物法和速率散射比浊法,对122例选择性剖宫产儿脐动脉血纤溶酶活性和IgG、IgM、IgA、C3、C4进行检测,并以150例自然产儿脐动脉血作对照。结果(1)选择性剖宫产儿脐血纤溶酶的活性显著低于对照组(P<0.01)。(2)选择性剖宫产儿脐血IgG、IgM、C3、C4均显著低于对照组(P<0.01、P<0.05、P<0.01、P<0.05)。(3)两组脐血IgA含量差异无统计学意义(P>0.05)。结论(1)选择性剖宫产新生儿湿肺、肺透明膜病等的发生率上升。(2)选择性剖宫产儿对感染的抵抗力较自然产儿更为低下,易患感染性疾病。(3)选择性剖宫产与自然产均使子宫内膜受损,作为黏膜局部保护性抗体的IgA均发挥重要的作用。     

Stem cells from umbilical cord blood

The study of hematopoiesis, the generation of blood cell lines throughout life, has provided conceptual, experimental, and therapeutic approaches useful to all stem cell biologists. From a clinical perspective, no other area of stem cell biology has been applied as successfully as has transplantation of bone marrow and cord blood for the treatment of blood diseases. In the last few years, research in stem cell biology has expanded rapidly to include the study of stem cells from embryonic, fetal, and various adult tissues, engendering novel perspectives regarding the identity, origin, and full therapeutic potential of tissue-specific stem cells. Rather than focusing on the use of cord blood stem cells for reconstitution of bone marrow, this article reviews the biology of stem cells found in the cord blood in the context of cell plasticity and their therapeutic potential for repair of the nervous system.     

The intrapartum content of toxic metals in maternal blood and umbilical cord blood

The concentrations of cadmium, lead and total mercury were determined by atomic absorption spectrometry in maternal blood and umbilical cord blood collected during the III-rd stage of term delivery from 56 mother-neonate pairs. Cadmium and mercury levels measured on both sides of placenta did not differ significantly while lead levels in maternal blood were significantly higher than its cord blood values. In all three metals studied, the concentrations in maternal blood strongly correlated with the corresponding cord blood values. A significant, positive correlation was established between the parity of the examined women and the umbilical cord blood contents of lead and mercury. The obtained results support the opinion that human placenta does not form an effective barrier to toxic metal intake by the fetus.     

Immunoglobulin content of the amniotic fluid and umbilical cord blood]

The content of immunoglobulins IgG, IgA and IgM and total protein in amniotic fluid and foetal serum of healthy pregnant women and of pregnant women with anti-D-antibodies has been determined by the single radial immunodiffusion and biuret method. IgG and IgA was detectable in all samples of amniotic fluid, whereas IgM was only present in 10 p.c. IgA increased in amniotic fluid to the end of pregnancy and it can indicate the maturity of fetus. The pregnant women with anti-D-antibodies have high IgG values in the amniotic fluid with the begin of 34th week of pregnancy.     

The effect of umbilical cord blood cytokines on clonogenicity of hemopoietic stem cells isolated from umbilical cord blood

Human umbilical cord blood contains haematopoietic stem cells, which are a potential source of cells for hematopoietic transplants. Early cord blood hematopoietic cells are influenced by so called proinflammatory cytokines, which are present in cord blood serum. In this study we tried to correlate the concentration of these cytokines with the number, viability and clonogenicity of cord blood mononuclear cells. Accordingly, cord blood samples were harvested by employing an "open" collection method. Subsequently, we measured in those samples the concentration of selected pro inflammatory cytokines (Il-1 alpha, Il-1 beta, Il-6, Il-8 and TNF alpha), number of mononuclear cells and evaluated in vitro clonogenicity of myeloid progenitors (CFU-GM). We found the negative correlation between number of mononuclear cells and concentration of TNF alpha, and between number of detectable CFU-GM and concentration of IL-1 beta. Other cytokines, which were studied in this report did not correlate with evaluated parameters.     

Implication of cord blood myeloperoxidase but not of soluble p-selectin levels in preterm deliveries

Although maternal amniotic and vaginocervical cytokines are known to play a role in triggering preterm delivery, the effects of activating fetal phagocytes and platelets are not clear. In an attempt to clarify this issue, we measured levels of myeloperoxidase (MPO), a phagocyte activation marker, and soluble p-selectin (sCD62p), a platelet activation marker, in umbilical cord blood samples from 2200 consecutive cord blood collections, 106 of which were from preterm infants. MPO and sCD62p levels were correlated to gestational age and preterm delivery. It was found that MPO levels were significantly higher in preterm infants and were not significantly correlated to gestational age. In contrast, sCD62p levels were lower in preterm infants and were negatively correlated to gestational age. In summary, we showed that fetal phagocyte activation as demonstrated by higher cord blood MPO levels is associated with preterm delivery, but platelet activation as shown by lower sCD62p levels is not. This suggests that fetal phagocyte activation may be implicated in preterm delivery, and subsequently in prematurity-related inflammatory insults.     

Prostacyclin does not influence placental blood pool in vivo

In 20 healthy pregnant women placental blood pool was estimated by means of placental scintigrams before, during and after infusion of either prostacyclin (PGI2) or placebo for 10 min to study the effect of PGI2 on the local regulation of uterine blood flow. There was no difference in the mean number of counts between the PGI2- and the placebo-treated group. Therefore no effect of PGI2 on uteroplacental blood pool could be detected in healthy gravidae.     

Effect of delays in collection or analysis on the results of umbilical cord blood measurements

Changes in umbilical cord blood pH, PO2 and PCO2 were measured when blood was stored in preheparinized polyethylene syringes in the refrigerator for up to 6 h after delivery, and when there was delayed sampling up to 1 h after delivery from umbilical cord segments left at room temperature. Blood stored in the refrigerator usually showed a decrease in pH and increases in PO2 and PCO2, but the mean rates of change were small: -0.005 units/h for pH; +0.06 kPa/h for PCO2 and +0.03 kPa/h for PO2. Changes in the three variables in blood collected from umbilical cords up to 1 h after delivery were small and not systematic. Much of the variation was within the limits of accuracy of the ABL-3 (Radiometer) blood-gas analyser. The results showed that while immediate collection and analysis of umbilical cord blood is advisable for the greatest accuracy, it is not essential. As long as the delay is not excessive, the results can still be used as a useful guide to the biochemical condition of an infant at birth.     

Effect of delays in collection or analysis on the results of umbilical cord blood measurements

Summary. Changes in umbilical cord blood pH, P o₂ and P co₂ were measured when blood was stored in preheparìnized polyethylene syringes in the refrigerator for up to 6 h after delivery, and when there was delayed sampling up to 1 h after delivery from umbilical cord segments left at room temperature. Blood stored in the refrigerator usually showed a decrease in pH and increases in P o ₂ and P co ₂, but the mean rates of change were small: - 0.005 units/h for pH; +0.06 kPa/h for P co ₂ and +0.03 kPa/h for P o ₂. Changes in the three variables in blood collected from umbilical cords up to 1 h after delivery were small and not systematic. Much of the variation was within the limits of accuracy of the ABL-3 (Radiometer) blood-gas analyser. The results showed that while immediate collection and analysis of umbilical cord blood is advisable for the greatest accuracy, it is not essential. As long as the delay is not excessive, the results can still be used as a useful guide to the biochemical condition of an infant at birth.     

Patients' knowledge of umbilical cord blood banking

OBJECTIVE: To determine patients' knowledge of umbilical cord blood banking (UCBB). METHODS: A questionnaire was administered. Part 1 queried issues of familiarity with the term UCBB. Those patients with any awareness of UCBB were provided with part 2, asking more detailed questions that assessed knowledge. RESULTS: Four hundred twenty-five patients completed the survey; 37% had no knowledge of UCBB. Older patients and those with higher degrees of education were more aware of UCBB, and the greatest disparity of knowledge was noted among Native American patients (p < 0.001). Of patients indicating familiarity with UCBB, 2.6% felt "extremely knowledgeable," while 74% felt "minimally informed." Fifty percent of the patients were misinformed that UCBB was only for "the child that I will deliver." Seventy-one percent of patients were not planning UCBB, with "expense" and "insufficient knowledge" as the primary reasons cited. Only 14% of patients were educated about UCBB by their nurse or obstetrician, although 90% of patients expected their obstetrician to answer their questions on UCBB. CONCLUSIONS: Patients are poorly informed about UCBB, especially ethnic minorities, younger patients and those with lesser degrees of education. Few patients receive UCBB education from health care providers, yet most patients expect their obstetrician to be able to answer questions on UCBB. Lack of knowledge and expense remain barriers to UCBB. Opportunities to educate patients and obstetric providers on UCBB should be pursued.