Umbilical cord blood collection before placental delivery during cesarean delivery increases cord blood volume and nucleated cell number available for transplantation.

OBJECTIVE: We sought to determine whether umbilical cord blood collection during cesarean delivery can be improved by collecting cord blood before delivery of the placenta. STUDY DESIGN: Patients undergoing cesarean delivery were randomly assigned to cord blood collection before or after placental delivery. Closed sterile collection systems were used for blood sampling. Cord blood characteristics and maternal outcome parameters were compared between the 2 groups. RESULTS: A total number of 40 patients were available for analysis. No differences in maternal and neonatal characteristics were found. A larger amount of cord blood volume (mean +/- SEM, 93 +/- 7.5 vs 66 +/- 6.6 mL; P =.013) and total nucleated cell number (11.1 +/- 1.2 vs 7.4 +/- 0.8 x 10(8) cells; P =.026) was obtained in the samples collected before compared with those collected after placental delivery. Similarly, there was a trend toward higher total CD34(+) cell number in samples collected in situ (30.0 +/- 6.0 vs 17.4 +/- 2.4 x 10(5) cells; P =.076). Estimated intraoperative blood loss, difference between prepartum and postpartum hemoglobin values, operating time, and puerperal infection rates were similar in both groups. CONCLUSION: If a cesarean delivery is performed, cord blood sampling is more efficacious if performed before delivery of the placenta. This collection method seems beneficial and safe and might therefore be preferably used for related, as well as unrelated, cord blood stem cell banking and transplantation.

Tissue-specific expression of two genes for sucrose synthase in carrot (Daucus carota L.).

Sucrose synthase, which cleaves sucrose in the presence of uridine diphosphate (UDP) into UDP-glucose and fructose, is thought to be a key determinant of sink strength of heterotrophic plant organs. To determine the roles of the enzyme in carrot, we characterized carrot sucrose synthase at the molecular level. Two genes (Susy*Dc1 and Susy*Dc2) were isolated. The deduced amino acid sequences are 87% identical. However, the sequences upstream of the translation initiation codons are markedly different, as are the expression patterns of the two genes. Susy*Dc2 was exclusively expressed in flowers. Transcripts for Susy*Dc1 were found in stems, in roots at different developmental stages, and in flower buds, flowers and maturing seeds, with the highest levels in strong utilization sinks for sucrose such as growing stems and tap root tips. Expression of Susy*Dc1 was regulated by anaerobiosis but not by sugars or acetate. The carrot sucrose synthase protein is partly membrane-associated and this insoluble form may be directly involved in cellulose biosynthesis. Tap roots of the carrot cultivar used accumulated starch in the vicinity of the vascular bundles, which correlated with high sucrose synthase transcript levels. This finding suggests that soluble sucrose synthase in tap roots channels sucrose towards starch biosynthesis. Starch accumulation appears to be transient and may be involved in sucrose partitioning to developing tap roots.

[Prenatal diagnosis with fetal cells in maternal blood: report of experiences in Basal]. / Pränatale Diagnostik mittels fetaler Zellen im mütterlichen Blut: ein Erfahrungsbericht aus Basel.

Currently prenatal diagnosis relies on invasive procedures such as chorion villus sampling (CVS) or amniocentesis (AC). Many parents are reluctant to expose themselves and their child to the small, but significant risk posed by these procedures to mother and child. There is, hence, a great need for a risk-free non-invasive alternative. To achieve this goal most research has been focussed on enriching fetal cells from the blood of pregnant women. The erythroblast has emerged as the target cell of choice, since it is abundant in the early fetus, rare in normal adult blood, and since it has a very short half life, there is no risk of obtaining cells from previous pregnancies. Most enrichment protocols rely either on magnetic- or fluorescent activated cell sorting (MACS and FACS) using fetal specific antibodies. These enriched cells can be examined by FISH (fluorescence in-situ hybridisation) for the presence of the most common fetal chromosomal aneuploidies (13, 18, 21, X and Y) or by polymerase chain reaction (PCR) on singly manipulated cells for genetic disorders. The efficacy in detecting fetal aneuploidies is currently being evaluated in a phase II clinical trial under the auspices of the NIH-NICHD, the so-called NIFTY Trial, in which our group is a participant. By modifying our enrichment protocols we have recently been able to obtain detection sensitivities of almost 80%, thereby renewing our optimism that this methodology provides a solid basis for an effective non-invasive prenatal diagnostic test.

Stages of transformation in the development of N-butyl-N-(4-hydroxybutyl)-nitrosamine-induced transitional cell carcinomas in the urinary bladder of rats.

The histogenesis of papillary and nonpapillary transitional cell carcinomas were studied morphologically and autoradiographically in 177 female Wistar rats after oral application of N-butyl-N-(4-hydroxybutyl)-nitrosamine with varying exposure and induction times. By far the largest proportion of carcinomas developed by a malignant transformation of preexisting papillomas or their precursors, the papillary hyperplasias. The transition into a focally malignant growth did not take place abruptly, but occurred stepwise through different successive stages of transformation, each having its own distinct morphological character. The first stage consisted of a focal, sharpely defined cellular atypia. In a further stage carcinomata in situ developed out of the atypical foci and progressed finally in a last stage of transformation into a circumscript infiltrative growth. The successive development of each stage occurred independent of any further carcinogen application after transformation was initiated at the molecular level. The number of papillomas with transformation stages increased with a lengthening of the exposure and induction time. 74.4% of all the registered papillomas had been transformed. Consequently papillomas must be considered potentially highly malignant. The 3H-TdR index was 4.2 times higher in atypical urothelial areas (7.6%) and 7.5 times higher in carcinomata in situ (14.3%) than in the surrounding papillomatous structures which appeared light microscopically benign. The latter demonstrated a rather constant 3H-TdR index, whether they bordered on atypical foci (1.8%) or carcinomata in situ (1.9%). The length of exposure and induction time exercised no significant influence on the degree of proliferative activity. The development of transitional cell carcinomas from a primary carcinoma in situ (intraurothelial carcinoma) played a much less significant role.