Search results for "Plexus"

In Vivo Imaging of Enteric Neuronal Networks in Humans Using Confocal Laser Endomicroscopy

2012

Management of large dorsal diffuse plexiform neurofibroma

2014

Abstract Neurofibromas are considered one of the hallmark signs of neurofibromatosis type 1(NF1). Diffuse plexiform neurofibroma is a congenital NF1-associated tumor, characterized by overgrowth and interference with function of the affected area. The rich vascular plexus associated with neurofibromas, together with their infiltrative pattern, makes them difficult to eradicate. Complications of neurofibromas are rare but include malignant transformation and potentially lifethreatening hemorrhages. The use of the term “giant” to define a neurofibroma is controversial because there is no clear consensus and descriptions are limited to few case reports. We report a case of a large dorsal diffu…

Alterations in the organization of the isocortical layer I in trisomy 22.

1999

The isocortical layer I of human fetal brains obtained from different cases of chromosomal abnormalities (trisomy 18, 21, 22) and controls without pathological disturbances were investigated histologically and immunohistochemically by using the antibodies SMI 311, SMI 35 and SMI 81 (SNAP 25) as well as antibodies against GAP 43 and calretinin. In cases of trisomy 22 the Cajal-Retzius cells in Nissl-sections and in SMI 311-immunopreparations do not reveal any alterations regarding their location or morphology. However, the axonal plexus, selectively labelled with SMI 35, normally located in layer Ib, is malpositioned in Ia. Likewise, SNAP 25- and GAP 43-immunoreactive structures, which were …

EGFL7 ligates αvβ3 integrin to enhance vessel formation

2013

Angiogenesis, defined as blood vessel formation from a preexisting vasculature, is governed by multiple signal cascades including integrin receptors, in particular integrin αVβ3. Here we identify the endothelial cell (EC)-secreted factor epidermal growth factor-like protein 7 (EGFL7) as a novel specific ligand of integrin αVβ3, thus providing mechanistic insight into its proangiogenic actions in vitro and in vivo. Specifically, EGFL7 attaches to the extracellular matrix and by its interaction with integrin αVβ3 increases the motility of EC, which allows EC to move on a sticky underground during vessel remodeling. We provide evidence that the deregulation of EGFL7 in zebrafish embryos leads …

Plasticity of mouse enteric synapses mediated through endocannabinoid and purinergic signaling

2012

The myenteric and submucosal plexuses of the enteric nervous system (ENS) exist as interconnected integrative nerve networks within the wall of the gastrointestinal (GI) tract. Activity of the ENS is responsible for the control of the digestive and protective functions of the gut.1 Synaptic transmission between enteric neurons propagates information from intrinsic afferent neurons to interneurons, and then from interneurons to motor neurons that control final effectors such as smooth muscle and the secretory epithelium. Acetylcholine (ACh) is the major excitatory neurotransmitter in the myenteric plexus, acting on nicotinic receptors at synapses between neurons and on muscarinic receptors a…

Axons take a dive

2014

In the walls of the lateral ventricles of the adult mammalian brain, neural stem cells (NSCs) and ependymal (E1) cells share the apical surface of the ventricular-subventricular zone (V-SVZ). In a recent article, we show that supraependymal serotonergic (5HT) axons originating from the raphe nuclei in mice form an extensive plexus on the walls of the lateral ventricles where they contact E1 cells and NSCs. Here we further characterize the contacts between 5HT supraependymal axons and E1 cells in mice, and show that suprependymal axons tightly associated to E1 cells are also present in the walls of the human lateral ventricles. These observations raise interesting questions about the functio…

An anatomical fetal brain structure and a normal variant mimicking anomalies on routine neurosonographic imaging: report of two cases

2004

We present two cases in which an anatomical structure, the calcar avis, and a normal variant, a bifid choroid plexus, mimicked abnormalities on routine prenatal ultrasound examination. To the best of our knowledge these pitfalls have only been described in neonates. A familiarity with these false images is important to avoid erroneous diagnoses.

Organisation and maturation of the human thalamus as revealed by CD15

2001

The distribution of the CD15 antigen (CD15, 3-fucosyl-N-acetyl-lactosamine, Lewis x) has been studied immunohistochemically in the fetal human thalamus. Its changing patterns could be related to three successive, but overlapping, periods primarily due to its association with radial glial cells, neuropil, and neural cell bodies, respectively. From 9 weeks of gestation (wg), a subset of CD15-positive radial glial cells distinguished the neuroepithelium of the ventral thalamus, a characteristic also seen in the developing mouse. Distal processes of the radial glial cells converged at the root of the forebrain choroid tenia, which was also CD15 positive. From 13 wg until approximately 20 wg, CD…

Achalasie im Kindesalter: Eine separate Entität?

2007

Background Achalasia in childhood is rare, also the etiology and the pathogenesis of the early onset ort he disease is practically unknown. Little is known about the neuropathological changes in structure of the esophageal wall in non-hereditary, sporadic achalasia in children and ist differentiation to that in adults. The aim of our study was to examine the morphological properties or high-pressure zone of the lower esophageal sphincter in children who had undergone a Heller myotomy because of achalasia as well as to compare them with the pathological findings in adults. Methods Muscle biopsies of the smooth musculature, a 20 x 10 mm long segment of the myenteric of the distal esophagus (l…

Localization of latency-associated transcripts in the uterovaginal plexus of herpes simplex virus type 1 and 2 latently infected mice.

1997

The vagina and medulla of the adrenal gland of mice vaginally infected with herpes simplex virus (HSV) types 1 and 2 were examined in the latent stage of infection (5 to 51 weeks post-infection). RNA in situ hybridization with HSV-1 and -2 latency-associated transcript (LAT) RNA probes resulted in positively stained neuronal cell nuclei in the uterovaginal plexus, but not in the medulla of the adrenal gland. These organs were chosen because HSV antigens can be detected not only in the vaginal epithelium, but also in neurons of the uterovaginal plexus and in the medulla of the adrenal gland at the acute stage of genital infection. To our knowledge, this is the first report describing LATs in…