Arteries of the Lower Limb-Embryology, Variations, and Clinical Significance.

Objectives: The purpose of this article is to review the embryology of the lower limb arterial anatomy along with common variants and their clinical relevance.

Design: Embryologic variations of the lower limb arterial system may be explained by i.) persistence of primordial arterial segments, ii.

The Embryonic Ascent of the Kidney Revisited.

Although the embryonic kidney's ascent is well established, the intermediate morphological changes that occur during the process are unclear. To evaluate the morphological events that accompany the kidney's ascent, we examined serial sagittal sections from 24 embryos at 5-7 weeks gestation. Six specimens had bilaterally ascending kidneys that were between the levels of the second to fifth lumbar vertebrae, and each kidney had a primitive renal cortex surrounding clusters of ampullae, which branched from the pelvis, and a dense tissue band that connected the renal cortex with the embryonic adrenal cortex or celiac ganglia, and there was no adipose capsule or renal artery.

Topographical anatomy of the intestines during in utero physiological herniation.

Because most malrotations of the small intestine are thought to occur during repackaging, the location of the intestine should vary less during physiological herniation than afterward. Examination of serial sagittal sections of 27 embryos and fetuses (gestational age 6-9 weeks; crown-rump length 15-45 mm) during herniation showed that the jejunum and ascending colon passed through a small opening of the hernia sac at the levels of the stomach and pancreas in 16 specimens. Below the pancreas, a definite mesentery extended between the ascending and descending colon in the abdominal cavity.

Germline Development of Genetically Female Nile Tilapia (Oreochromis niloticus) Reared under Different Temperature Regimes.

In teleosts, elevated temperature during embryogenesis can act on germline cell development, which in turn plays a role for sexual fate. In Nile tilapia, a species with high-temperature-induced masculinization, little is known about the effects of increased temperature on gonadal development in non-masculinized females. The aim of the present work was to investigate persistent effects on the germline of genetically female (XX) Nile tilapia reared at normal (28°C) or elevated temperature (36°C) during the critical time of gonadal sex differentiation at 10 to 20 days post fertilization.

Perineal raphe with special reference to its extension to the anus: a histological study using human fetuses.

The raphe of the human penis and scrotum is considered to develop secondarily after disappearance of the initial midline seam by fusion of the bilateral genital folds. However, the fetal development was still obscure. We examined histological sections of 30 fetuses (17 males and 13 females) at 10-15 weeks.

Fetal growth of the anal sinus and sphincters, especially in relation to anal anomalies.

Purpose And Methods: The anal sinuses, small furrows above the pectinate line, sometimes form perianal abscesses in adults. We examined the pattern of fetal growth of the anal sinus and sphincters using 22 mid-term (8-18 weeks) and 6 late-stage (30-38 weeks) fetuses.

Results: In mid-term fetuses, the external and internal sphincters gradually increased in thickness, depending on specimen size (from 0.

Altered regulation of Prox1-gene-expression in liver tumors.

Background: Prospero-related homeobox 1 (Prox1) transcription factor was described as a tumor-suppressor gene in liver tumors. In contrast, Prox1 knock out in murine embryos drastically reduces proliferation of hepatoblasts.

Methods: We have studied the expression of Prox1 in normal liver, liver cirrhosis and peritumoral liver samples in comparison to hepatocellular (HCC) and cholangiocellular carcinoma (CCC) at mRNA, protein and functional levels.

Keratoepithelin reverts the suppression of tissue factor pathway inhibitor 2 by MYCN in human neuroblastoma: a mechanism to inhibit invasion.

Neuroblastoma is the most frequent solid malignancy of children. The most reliable prognostic factor in neuroblastoma is the amplification status of the MYCN oncogene, but exceptions from this rule have been observed. Recently we have demonstrated that keratoepithelin (BIGH3, TGFBI) expression significantly reduces proliferation and invasion of neuroblastomas in vitro and in vivo.

Lymph heart in chick--somitic origin, development and embryonic oedema.

The lymph heart is a sac-like structure on either side of avian tail. In some adult birds, it empties the lymph from the copulatory organ; however, during embryonic development, it is thought to circulate extra-embryonic lymph. Very little is known about the origin, innervation and the cellular changes it undergoes during development.

Prospero-related homeobox 1 (Prox1) is a stable hepatocyte marker during liver development, injury and regeneration, and is absent from "oval cells".

The aim of this study was to analyse the changes of Prospero-related homeobox 1 (Prox1) gene expression in rat liver under different experimental conditions of liver injury, regeneration and acute phase reaction, and to correlate it with that of markers for hepatoblasts, hepatocytes, cholangiocytes and oval cells. Gene expression was studied at RNA level by RT-PCR, and at protein level by immunohistochemistry. At embryonal stage of rat liver development (embryonal days (ED) 14-16) hepatoblasts were found to be Prox1(+)/Cytokeratin (CK) 19(+) and alpha-fetoprotein (AFP)(+), at this stage Prox1(-)/CK19(+)/AFP(-) small cells (early cholangiocytes?) were identified.

The neurotrophin receptor TrkB cooperates with c-Met in enhancing neuroblastoma invasiveness.

Neuroblastoma is the most frequent extracranial solid malignancy of childhood with a high mortality in advanced tumour stages. The hallmark of neuroblastoma is its clinical and biological heterogeneity. The molecular mechanisms leading to favourable or unfavourable tumour behaviour are still speculative.

Hepatocyte growth factor/c-Met signaling promotes the progression of experimental human neuroblastomas.

Neuroblastoma is the most frequent solid childhood malignancy. Despite aggressive therapy, mortality is high due to rapid tumor progression to advanced stages. The molecules and mechanisms underlying poor prognosis are not well understood.

VEGF coordinates interaction of pericytes and endothelial cells during vasculogenesis and experimental angiogenesis.

Biological activities of vascular endothelial growth factor (VEGF) have been studied extensively in endothelial cells (ECs), but few data are available regarding its effects on pericytes. In murine embryoid body cultures, VEGF-induced expression of desmin and alpha-smooth muscle actin (alpha-SMA) in CD-31+ cells. The number of CD-31+/desmin+ vascular chords increased with VEGF treatment time and peaked during a differentiation window between 6 and 9 days after plating.