Talk:BGDB Gastrointestinal - Fetal

BGD Internal Links 2009 5. Fetal

Development of c-kit immunopositive interstitial cells of Cajal in the human stomach

J Cell Mol Med. 2010 May;14(5):1125-34. doi: 10.1111/j.1582-4934.2009.00725.x.

Radenkovic G, Savic V, Mitic D, Grahovac S, Bjelakovic M, Krstic M. Source Department of Histology and Embryology, Faculty of Medicine, University of Nis, Nis, Serbia. radenkog@scnet.yu

Abstract

Interstitial cells of Cajal (ICC) include several types of specialized cells within the musculature of the gastrointestinal tract (GIT). Some types of ICC act as pacemakers in the GIT musculature, whereas others are implicated in the modulation of enteric neurotransmission. Kit immunohistochemistry reliably identifies the location of these cells and provides information on changes in ICC distribution and density. Human stomach specimens were obtained from 7 embryos and 28 foetuses without gastrointestinal disorders. The specimens were 7-27 weeks of gestational age, and both sexes are represented in the sample. The specimens were exposed to anti-c-kit antibodies to investigate ICC differentiation. Enteric plexuses were immunohistochemically examined by using anti-neuron specific enolase and the differentiation of smooth muscle cells (SMC) was studied with anti-alpha smooth muscle actin and anti-desmin antibodies. By week 7, c-kit-immunopositive precursors formed a layer in the outer stomach wall around myenteric plexus elements. Between 9 and 11 weeks some of these precursors differentiated into ICC. ICC at the myenteric plexus level differentiated first, followed by those within the muscle layer: between SMC, at the circular and longitudinal layers, and within connective tissue septa enveloping muscle bundles. In the fourth month, all subtypes of c-kit-immunoreactivity ICC which are necessary for the generation of slow waves and their transfer to SMC have been developed. These results may help elucidate the origin of ICC and the aetiology and pathogenesis of stomach motility disorders in neonates and young children that are associated with absence or decreased number of these cells. PMID 19298525

Three-dimensional MRI volumetric measurements of the normal fetal colon

AJR Am J Roentgenol. 2009 Mar;192(3):761-5. Rubesova E, Vance CJ, Ringertz HG, Barth RA.

Department of Radiology, Lucile Packard Children's Hospital, Stanford University, 720 Welch Rd., Stanford, CA 94305, USA.

Abstract

OBJECTIVE: The use of fetal MRI markedly improves characterization of abdominal congenital anomalies. Accurate prenatal diagnosis of the level and cause of congenital intestinal obstruction is desired for optimal parental counseling and perinatal care. Because accurate diagnosis would be aided by nomograms of colonic volume, this study was conducted to determine normal colonic volumes at different gestational ages.

MATERIALS AND METHODS: This retrospective study consisted of a review of 83 fetal MRI examinations performed on fetuses with no gastrointestinal abnormalities. MRI was performed with a 1.5-T system. Axial, sagittal, and coronal T1-weighted fast gradient-refocused echo images were acquired at TR/TE, 165/2.6; flip angle, 90 degrees; matrix size, 384 x 192; slice thickness, 5 mm; field of view, 38 cm(2). Two investigators determined the region of interest in the colon by outlining areas of high signal intensity of meconium slice by slice. They then calculated colonic luminal volume in the regions of interest. Colonic luminal volumes were reported relative to gestational age and abdominal circumference. Normative curves were generated, and interobserver and intraobserver analyses were performed.

RESULTS: Seventeen of the 83 fetuses (20%) were excluded because of movement artifacts on the images. Normal colonic luminal volume increased exponentially with gestational age and abdominal circumference. The range of colonic luminal volumes at 20-37 weeks' gestational age was 1.1 - 65 mL. Variation of volume was greater at advanced gestational age. Interobserver and intraobserver correlation was good.

CONCLUSION: This study yielded preliminary volumetric measurements of the normal fetal colon at 20-37 weeks of gestational age that suggest the fetal colon grows exponentially.

Images

Normal fetus at 32 weeks of gestation http://www.ajronline.org/content/vol192/issue3/images/large/03_08_1504_01.jpeg

PMID 19234275

http://www.ajronline.org/cgi/content/full/192/3/761