Development of the Arterial Supply of the Spinal Cord Tissue Based on Radioanatomical and Histological Studies in Cattle

Purpose Angiographic techniques have gained increasing importance in suspected vascular disease of the spinal cord. This demands an advanced understanding of spinal cord blood vessel anatomy and its embryologically founded broad spectrum of variations. The aim of this study was to improve knowledge on contentious issues concerning the development of spinal cord arterial supply in higher mammals and to offer visual information of high didactic value. Methods The prenatal development was examined in cattle, using multiplanar high-resolution microangiography of injected specimens and microscopic sections. The gestational ages of the 15 specimens were between the late embryonic and the early fetal period (5–11 weeks). Microangiography of the human spinal cord from an earlier published study were used to envisage an adult arterial vascularization pattern in higher mammals. Results Establishment of the unpaired anterior spinal artery (ASA) goes through two procedures of reconfiguration until achieving its final design. Regression of the primarily established anteromedian tract is observed in cattle fetuses of 9–10 weeks. Return to the ontogenetic disposition of bilateral symmetry and a burst of vascularization from all parts of the spinal meninges follow and include the anterior median fissure as a preferred vascular pathway. Large sulcal/central arteries longitudinally anastomosing between each other emerge on both sides of the midline. The embryological pattern of exclusive peripheral medullary supply must have been converted into a combined system of predominant central (centrifugal) supply of the enlargements before a final unpaired ASA can be reconstructed. Conclusion Previous investigators focused on the early embryonic development of spinal cord arteries and missed the profound remodeling of the vascular architecture in the early fetal period.

Response to Therapeutic Abortion in Lactating Dairy Cows Carrying Dead Twins during the Late Embryo/Early Fetal Period

This study examined the dose–response effect of prostaglandin F2α (PGF2α) when used to induce abortion in cows with two dead twins at pregnancy diagnosis 28–34 days post-AI (late embryonic period: LE) or at pregnancy confirmation 49–55 days post-AI (early fetal period: EF). The study population consisted of 415 cows receiving a single PGF2α dose (PG1 group: 254 LE and 161 EF cows) and 200 receiving a 1.5 × PGF2α dose (PG1.5 group: 121 LE and 79 EF cows). The induced abortion rate was significantly lower (chi-square test; p < 0.0001) in the EF (34.6%) than LE cows (88%), and was also reduced (p = 0.001) in the EF PG1 group (28%) compared with the EF PG1.5 group (48.1%). High milk production (≥45 kg) was the only factor influencing the induced abortion rate in LE cows (odds ratio 0.2; p < 0.0001), whereas the odds ratio for induced abortion of PG1.5 cows was 2.3 (p = 0.005) in EF cows. In conclusion, an increased PGF2α dose had no effect on abortion induction during the late embryonic period and its rate was inversely associated with milk production. This higher PGF2α dose did, however, offer benefits during the early fetal period.

Expression of Connexins 37, 43 and 45 in Developing Human Spinal Cord and Ganglia

Direct intercellular communication via gap junctions has an important role in the development of the nervous system, ranging from cell migration and neuronal differentiation to the formation of neuronal activity patterns. This study characterized and compared the specific spatio-temporal expression patterns of connexins (Cxs) 37, 43 and 45 during early human developmental stages (since the 5th until the 10th developmental week) in the spinal cord (SC) and dorsal root ganglia (DRG) using double immunofluorescence and transmission electron microscopy. We found the expression of all three investigated Cxs during early human development in all the areas of interest, in the SC, DRG, developing paravertebral ganglia of the sympathetic trunk, notochord and all three meningeal layers, with predominant expression of Cx37. Comparing the expression of different Cxs between distinct developmental periods, we did not find significant differences. Specific spatio-temporal pattern of Cxs expression might reflect their relevance in the development of all areas of interest via cellular interconnectivity and synchronization during the late embryonic and early fetal period of human development.

Human embryonic organocomlexes formation and their structures dynamics

Complex structures are formed in the human embryo – embryonic organocomplexes. They are the rudiments of two or more organs and are the source of divergence. Embryonic organocomplexes appear in the embryonic and early fetal period of the organism’s development.

Structural proteins of plasmolemma of the jejunum absorbing enterocytes of cattle fetus in early fetal period

The data on the concentration of structural proteins of plasmolemma of the absorption enterocytes of the cattle fetus in the early fetal period are presented. Changes in the protein composition of the apical and basolateral membranes of enterocytes are manifested, characterized not only by changes in their ratio within different cell domains, but also by the dynamic redistribution of the number of different fractions of polypeptides between the poles of these cells. Analysis of the results of electrophoresis of apical membranes of the cattle fetus enterocytes in the early fetal period indicates a decrease in the content of low molecular weight protein fractions and an increase in high molecular weight. In the apical membranes of enterocytes of two-month-old cattle fetus, 25 protein fractions with a molecular weight of 9.6 to 205 kDa were detected. In the basolateral membranes revealed 23 protein fractions with a molecular weight of 9.6 to 120 kDa. High molecular weight fractions of polypeptides with molecular weights of 250 kDa and 300 kDa appear from the age of three months of embryos of calves. In the basolateral membranes of enterocytes, there is a slight decrease in the content of low molecular weight protein fractions, and from the four months of age of cattle fetus, high molecular weight fractions of polypeptides with molecular weights of 22.5 kDa and 155 kDa appear, which are absent in basolateral membranes of enterocytes. Two-month-old fetus lack proteins with a molecular weight of 19 kDa, 24 kDa, and 66 kDa in the apical part, whereas proteins with a mass of 22.5 kDa, 155 kDa, 170–185 kDa, and 205 kDa are absent on the basolateral membrane. In the apical membrane of enterocytes significantly more proteins with a low molecular weight of 9.6-14.2 kDa (1.56 times; P ≤ 0.001), whereas in the basolateral membrane a significantly higher concentration of proteins with a molecular weight of 15.5 kDa (2.06 times; P ≤ 0.001) and 17 kDa (3.62 times; P ≤ 0.001).

Structural proteins of plasmolemma of the jejunum absorbing enterocytes of cattle fetus in early fetal period

The data on the concentration of structural proteins of plasmolemma of the absorption enterocytes of the cattle fetus in the early fetal period are presented. Changes in the protein composition of the apical and basolateral membranes of enterocytes are manifested, characterized not only by changes in their ratio within different cell domains, but also by the dynamic redistribution of the number of different fractions of polypeptides between the poles of these cells. Analysis of the results of electrophoresis of apical membranes of the cattle fetus enterocytes in the early fetal period indicates a decrease in the content of low molecular weight protein fractions and an increase in high molecular weight. In the apical membranes of enterocytes of two-month-old cattle fetus, 25 protein fractions with a molecular weight of 9.6 to 205 kDa were detected. In the basolateral membranes revealed 23 protein fractions with a molecular weight of 9.6 to 120 kDa. High molecular weight fractions of polypeptides with molecular weights of 250 kDa and 300 kDa appear from the age of three months of embryos of calves. In the basolateral membranes of enterocytes, there is a slight decrease in the content of low molecular weight protein fractions, and from the four months of age of cattle fetus, high molecular weight fractions of polypeptides with molecular weights of 22.5 kDa and 155 kDa appear, which are absent in basolateral membranes of enterocytes. Two-month-old fetus lack proteins with a molecular weight of 19 kDa, 24 kDa, and 66 kDa in the apical part, whereas proteins with a mass of 22.5 kDa, 155 kDa, 170–185 kDa, and 205 kDa are absent on the basolateral membrane. In the apical membrane of enterocytes significantly more proteins with a low molecular weight of 9.6-14.2 kDa (1.56 times; P ≤ 0.001), whereas in the basolateral membrane a significantly higher concentration of proteins with a molecular weight of 15.5 kDa (2.06 times; P ≤ 0.001) and 17 kDa (3.62 times; P ≤ 0.001).

Critical Growth Processes for the Midfacial Morphogenesis in the Early Prenatal Period

Background: Congenital midfacial hypoplasia often requires intensive treatments and is a typical condition for the Binder phenotype and syndromic craniosynostosis. The growth trait of the midfacial skeleton during the early fetal period has been assumed to be critical for such an anomaly. However, previous embryological studies using 2-dimensional analyses and specimens during the late fetal period have not been sufficient to reveal it. Objective: To understand the morphogenesis of the midfacial skeleton in the early fetal period via 3-dimensional quantification of the growth trait and investigation of the developmental association between the growth centers and midface. Methods: Magnetic resonance images were obtained from 60 human fetuses during the early fetal period. Three-dimensional shape changes in the craniofacial skeleton along growth were quantified and visualized using geometric morphometrics. Subsequently, the degree of development was computed. Furthermore, the developmental association between the growth centers and the midfacial skeleton was statistically investigated and visualized. Results: The zygoma expanded drastically in the anterolateral dimension, and the lateral part of the maxilla developed forward until approximately 13 weeks of gestation. The growth centers such as the nasal septum and anterior portion of the sphenoid were highly associated with the forward growth of the midfacial skeleton (RV = 0.589; P < .001). Conclusions: The development of the midface, especially of the zygoma, before 13 weeks of gestation played an essential role in the midfacial development. Moreover, the growth centers had a strong association with midfacial forward growth before birth.