- Microvasculature of the esophagus and gastroesophageal junction: Lesson learned from submucosal endoscopy. [Review]
- WJWorld J Gastrointest Endosc 2016 Nov 16; 8(19):690-696
- Advanced therapeutic endoscopy, in particular endoscopic mucosal resection, endoscopic submucosal dissection, per-oral endoscopic myotomy, submucosal endoscopic tumor resection opened a new era where...
Advanced therapeutic endoscopy, in particular endoscopic mucosal resection, endoscopic submucosal dissection, per-oral endoscopic myotomy, submucosal endoscopic tumor resection opened a new era where direct esophageal visualization is possible. Combining these information with advanced diagnostic endoscopy, the esophagus is organized, from the luminal side to outside, into five layers (epithelium, lamina propria with lamina muscularis mucosa, submucosa, muscle layer, adventitia). A specific vascular system belonging to each layer is thus visible: Mucosa with the intra papillary capillary loop in the epithelium and the sub-epithelial capillary network in the lamina propria and, at the lower esophageal sphincter (LES) level with the palisade vessels; submucosa with the drainage vessels and the spindle veins at LES level; muscle layer with the perforating vessels; peri-esophageal veins in adventitia. These structures are particularly important to define endoscopic landmark for the gastro-esophageal junction, helpful in performing submucosal therapeutic endoscopy.
- Embracing change: striated-for-smooth muscle replacement in esophagus development. [Review]
- SMSkelet Muscle 2016 Aug 8; 6(1):27
- The esophagus functions to transport food from the oropharyngeal region to the stomach via waves of peristalsis and transient relaxation of the lower esophageal sphincter. The gastrointestinal tract,...
The esophagus functions to transport food from the oropharyngeal region to the stomach via waves of peristalsis and transient relaxation of the lower esophageal sphincter. The gastrointestinal tract, including the esophagus, is ensheathed by the muscularis externa (ME). However, while the ME of the gastrointestinal tract distal to the esophagus is exclusively smooth muscle, the esophageal ME of many vertebrate species comprises a variable amount of striated muscle. The esophageal ME is initially composed only of smooth muscle, but its developmental maturation involves proximal-to-distal replacement of smooth muscle with striated muscle. This fascinating phenomenon raises two important questions: what is the developmental origin of the striated muscle precursor cells, and what are the cellular and morphogenetic mechanisms underlying the process? Studies addressing these questions have provided controversial answers. In this review, we discuss the development of ideas in this area and recent work that has shed light on these issues. A working model has emerged that should permit deeper understanding of the role of ME development and maturation in esophageal disorders and in the functional and evolutionary underpinnings of the variable degree of esophageal striated myogenesis in vertebrate species.
- Biomechanical properties of an implanted engineered tubular gut-sphincter complex. [Journal Article]
- JTJ Tissue Eng Regen Med 2016 Nov 23
- Neuromuscular diseases of the gut alter the normal motility patterns. Although surgical intervention remains the standard treatment, preservation of the sphincter attached to the rest of the gut is c...
Neuromuscular diseases of the gut alter the normal motility patterns. Although surgical intervention remains the standard treatment, preservation of the sphincter attached to the rest of the gut is challenging. The present study aimed to evaluate a bioengineered gut-sphincter complex following its subcutaneous implantation for 4 weeks in rats. Engineered innervated human smooth muscle sheets and innervated human sphincters with a predefined alignment were placed around tubular scaffolds to create a gut-sphincter complex. The engineered complex was subcutaneously implanted in the abdomen of the rats for 4 weeks. The implanted tissues were vascularized. In vivo manometry revealed luminal pressure at the gut and the sphincter zone. Tensile strength, elongation at break and Young's modulus of the engineered complexes were similar to those of native rat intestine. Histological and immunofluorescence assays showed maintenance of smooth muscle circular alignment in the engineered tissue, maintenance of smooth muscle contractile phenotype and innervation of the smooth muscle. Electrical field stimulation induced relaxation of the smooth muscle of both the sphincter and the gut parts. Relaxation was partly inhibited by nitric oxide inhibitor indicating nitrergic contribution to relaxation. The present study has demonstrated for the first time a successfully developed and subcutaneously implanted a tubular human-derived gut-sphincter complex. The sphincteric part of Tubular Gut-Sphincter Complex (TGSC) maintained the basal tone characteristic of a native sphincter. The gut part also maintained its specific neuromuscular characteristics. The results of this study provide a promising therapeutic approach to restore gut continuity and motility. Copyright © 2016 John Wiley & Sons, Ltd.
- Internal anal sphincter: Clinical perspective. [Review]
- SSurgeon 2016 Nov 20
- CONCLUSIONS: Our understanding of the physiology and pharmacology of IAS has increased greatly in the last three decades. Additionally, there has been a rise in diagnostic and therapeutic techniques specifically targeting the IAS. Although these are promising, future research is required before these can be incorporated into the management algorithm.
- Breathing training on lower esophageal sphincter as a complementary treatment of gastroesophageal reflux disease (GERD): a systematic review. [Journal Article]
- EREur Rev Med Pharmacol Sci 2016; 20(21):4547-4552
- CONCLUSIONS: Among the non-surgical, non-pharmacological treatment modalities, the breathing training on diaphragm could play an important role in selected patients to manage the symptoms of GERD.
- Pneumatic Dilation of the Lower Esophageal Sphincter Can Now Be Successfully Performed Without Morbidity. [Journal Article]
- AJAm J Med Sci 2016; 352(5):443-447
- CONCLUSIONS: PD by an experienced gastroenterologist using general anesthesia, fluoroscopic guidance, Rigiflex balloon equipment and a specific repetitive technique can be successfully performed without perforation. Hence, the already known therapeutic efficacy of PD can now be combined with the knowledge that there is essentially no accompanying perforation rate.
- GABAergic Innervation of the Ciliary Ganglion in Macaque Monkeys - A Light and Electron Microscopic Study. [Journal Article]
- JCJ Comp Neurol 2016 Nov 16
- The vertebrate ciliary ganglion (CG) is a relay station in the parasympathetic pathway activating the iris sphincter and ciliary muscle to mediate pupillary constriction and lens accommodation, respe...
The vertebrate ciliary ganglion (CG) is a relay station in the parasympathetic pathway activating the iris sphincter and ciliary muscle to mediate pupillary constriction and lens accommodation, respectively. While the postganglionic motoneurons in the CG are cholinergic, as are their inputs, there is evidence from avian studies that GABA may also be involved. Here, we used light and electron microscopic methods to examine the GABAergic innervation of the CG in Macaca fascicularis monkeys. Immunohistochemistry for the gamma aminobutyric acid synthesizing enzyme glutamic acid decarboxylase (GAD) and choline acetyltransferase (ChAT) revealed that all CG neurons are contacted by ChAT-positive terminals. A subpopulation of 17.5% of CG neurons was associated with terminal boutons expressing GAD-immunoreactivity in addition. Double-labeling for GAD and synaptophysin confirmed that these were synaptic terminals. Electron microscopic analysis in conjunction with GABA-immunogold staining showed that: 1) GAD-positive terminals mainly target dendrites and spines in the perisomatic neuropil of CG neurons, 2) GABA is restricted to a specific terminal type, which displays intermediate features lying between classically excitatory and inhibitory endings, and 3) if a CG neuron is contacted by GABA-positive terminals, virtually all perisomatic terminals supplying it show GABA-immunoreactivity. The source of this GABAergic input and whether GABA contributes to a specific CG function remains to be investigated. Nevertheless, our data indicate that the innervation of the ciliary ganglion is more complex than previously thought, and that GABA may play a neuromodulatory role in the control of lens or pupil function. This article is protected by copyright. All rights reserved.
- Microsurgical Anatomy of the Oculomotor nerve. [Review]
- CAClin Anat 2016 Nov 18
- The oculomotor nerve supplies the extraocular muscles. It also supplies the ciliary and sphincter pupillae muscles through the ciliary ganglion. The nerve fibers leave the midbrain through the most m...
The oculomotor nerve supplies the extraocular muscles. It also supplies the ciliary and sphincter pupillae muscles through the ciliary ganglion. The nerve fibers leave the midbrain through the most medial part of the cerebral peduncle and enter the interpeduncular cistern. After the oculomotor nerve emerges from the interpeduncular fossa, it enters the cavernous sinus slightly lateral and anterior to the dorsum sellae. It enters the orbit through the superior orbital fissure, after exiting the cavernous sinus, to innervate the extraocular muscles. Therefore, knowledge of the detailed anatomy and pathway of the oculomotor nerve is critical for the management of lesions located in the middle cranial fossa and the clival, cavernous, and orbital regions. This review describes the microsurgical anatomy of the oculomotor nerve and presents pictures illustrating this nerve and its surrounding connective and neurovascular structures. This article is protected by copyright. All rights reserved.
- Correlation Between Echodefecography and 3-Dimensional Vaginal Ultrasonography in the Detection of Perineal Descent in Women With Constipation Symptoms. [Journal Article]
- DCDis Colon Rectum 2016; 59(12):1191-1199
- CONCLUSIONS: The study did not include a control group without symptoms.Three-dimensional endovaginal ultrasonography is a reliable technique for assessment of perineal descent. Using this technique, excessive perineal descent can be defined as displacement of the anorectal junction >1 cm and/or its position below the symphysis pubis on Valsalva maneuver.
New Search Next
- Convergence of inhibitory neural inputs regulate motor activity in the murine and monkey stomach. [Journal Article]
- AJAm J Physiol Gastrointest Liver Physiol 2016 Nov 1; 311(5):G838-G851
- Inhibitory motor neurons regulate several gastric motility patterns including receptive relaxation, gastric peristaltic motor patterns, and pyloric sphincter opening. Nitric oxide (NO) and purines ha...
Inhibitory motor neurons regulate several gastric motility patterns including receptive relaxation, gastric peristaltic motor patterns, and pyloric sphincter opening. Nitric oxide (NO) and purines have been identified as likely candidates that mediate inhibitory neural responses. However, the contribution from each neurotransmitter has received little attention in the distal stomach. The aims of this study were to identify the roles played by NO and purines in inhibitory motor responses in the antrums of mice and monkeys. By using wild-type mice and mutants with genetically deleted neural nitric oxide synthase (Nos1(-/-)) and P2Y1 receptors (P2ry1(-/-)) we examined the roles of NO and purines in postjunctional inhibitory responses in the distal stomach and compared these responses to those in primate stomach. Activation of inhibitory motor nerves using electrical field stimulation (EFS) produced frequency-dependent inhibitory junction potentials (IJPs) that produced muscle relaxations in both species. Stimulation of inhibitory nerves during slow waves terminated pacemaker events and associated contractions. In Nos1(-/-) mice IJPs and relaxations persisted whereas in P2ry1(-/-) mice IJPs were absent but relaxations persisted. In the gastric antrum of the non-human primate model Macaca fascicularis, similar NO and purine neural components contributed to inhibition of gastric motor activity. These data support a role of convergent inhibitory neural responses in the regulation of gastric motor activity across diverse species.