Download the Free Unbound MEDLINE PubMed App to your smartphone or tablet.
Available for iPhone, iPad, iPod touch, and Android.
sphincter muscle [keywords]
- A Novel Surgical Technique for Preserving Bladder Neck during Robotic-Assisted Laparoscopic Radical Prostatectomy; Preliminary Results. [JOURNAL ARTICLE]
- J Endourol 2014 Jul 21.
Objectives: To describe our new surgical technique for preserving bladder neck during robotic assisted laparoscopic radical prostatectomy (RALP) and to present the anatomy between bladder neck and prostate. Methods: Between, December 2012 and May 2014, 52 RALP surgeries were performed at our institute. Demographic, perioperative, and postoperative data were recorded. Quality of life (QoL) scores were assessed before RALP, after urethral catheter removal, at the 1st month of RALP. Fatty connective tissue between bladder neck and prostate was introduced, and circular muscle fibres of internal sphincter was seen, in all patients. Complications were classified according to Clavien-Dindo classification. Statistical analyses were performed. Results: Mean follow-up was 9.6 ± 5.2 months, mean age was 61.1 ± 6.5 years. Our novel surgical technique for preserving bladder neck was performed in 52 patients and they were continent after catheter removal as mean duration of catheter was 9.4 ± 1.4 days. However, there was significant difference in QoL before RALP and after catheter removal, but there was no statistically difference between before and 1 month after RALP (respectively; p<0.001, p=0.5). Furthermore, there was no complication related with bladder neck such as bladder neck stricture, acute/chronic urinary retention as well as no Clavien 3, 4, and 5 complications. Additionally, conventional laparoscopy and/or open surgery was not required in any of RALP case. Conclusion: Our novel technique provided very early continence as time of catheter removal after RALP, within short-term follow-up. These can help early recovery and develop QoL scores after RALP.
- Angiotensin IV induced contractions in human jejunal wall musculature in vitro. [JOURNAL ARTICLE]
- Peptides 2014 Jul 16.
Angiotensin II (AngII) has been reported to mediate contractile actions in rats and human jejunal wall musculature. However, except for one report showing the Angiotensin IV (AngIV) contractile effects on the internal anal sphincter of rats, no data is available describing the action of AngIV on smooth muscle in human small intestine. The aim of this study was to investigate the expression and localization of the enzymes responsible to AngIV formation, as well as the receptor, and to elucidate the contractile function of AngIV in the muscular layer of human jejunum in vitro. Jejunal smooth muscle was taken from 23 patients undergoing Roux-en-Y gastric bypass surgery and was used to record isometric tension in vitro in response to AngIV alone and in presence of losartan or PD123319. ELISA, western blot and immunohistochemistry were used to investigate the expression and localization of key components for AngIV formation: the enzymes Aminopeptidases-A, B, M, and the AngIV receptor insulin-regulated aminopeptidase (IRAP). AngIV elicited concentration-dependent contraction in both longitudinal and circular smooth-muscle preparation. Presence of losartan abolished AngIV-induced contraction, but not PD123319. The main peptide AngII, as well as the enzymes Aminopeptidase-A, B and M were detected in all muscle samples. Immunohistochemistry localized the enzymes and IRAP in the myenteric plexus between longitudinal and circular muscle layers. The present study indicates that all enzymes necessary for AngIV formation exist in human jejunal smooth muscle and that the contractile action elicited by AngIV is primarily mediated through the AngII type 1 receptor.
- Heme Oxygenase-1 Up-regulation Modulates Tone and Fibroelastic Properties of Internal Anal Sphincter. [JOURNAL ARTICLE]
- Am J Physiol Gastrointest Liver Physiol 2014 Jul 17.
Background & Aims: A compromise in the internal anal sphincter (IAS) tone and fibroelastic properties (FEP) plays an important role in rectoanal incontinence (RI). Herein, we examined the effects of (HO-1) upregulation on these IAS characteristics in young rats. Methods: We determined the effect of HO-1 upregulator hemin on HO-1 mRNA and protein expressions, and on basal IAS tone and its FEP before and after HO-1 inhibitor SnPPIX. For FEP, we determined the kinetics of the IAS smooth muscle responses, by the velocities of relaxation, and recovery of the IAS tone following 0Ca2+ and EFS. To characterize the underlying signal transduction for these changes, we determined the effects of hemin on RhoA/ROCKII, myosin-binding subunit of myosin light chain phosphatase (MYPT1), fibronectin, and elastin expression levels. Results: Hemin increased HO-1 mRNA and protein similar to the increases in the basal tone, and in the FEP of the IAS. Underlying mechanisms in the IAS characteristics are associated with increases in the genetic and translational expressions of RhoA/ROCKII, and elastin. Fibronectin expression levels on the other hand were found to be decreased following HO-1 upregulation. Conclusion: The results of our study show that hemin/HO-1 system regulates the tone and fibroelastic properties of IAS. Hemin/HO-1 system thus provides a potential target for the development of new interventions aimed at treatment of gastrointestinal motility disorders, specifically the age-related IAS dysfunction.
- Experimental Study on the Effect of Electrostimulation on Neural Regeneration After Oculomotor Nerve Injury. [JOURNAL ARTICLE]
- J Mol Neurosci 2014 Jul 15.
The oculomotor nerve can regenerate anatomically and histologically after injury; however, the degree of functional recovery of extraocular muscles and the pupil sphincter muscle was not satisfactory. Electrostimulation was one potential intervention that was increasingly being studied for use in nerve injury settings. However, the effect of electrostimulation on regeneration of the injured oculomotor nerve was still obscure. In this study, we studied the effects of electrostimulation on neural regeneration in terms of neurofunction, myoelectrophysiology, neuroanatomy, and neurohistology after oculomotor nerve injury and found that electrostimulation on the injured oculomotor nerve enhanced the speed and final level of its functional and electrophysiological recovery, promoted neural regeneration, and enhanced the selectivity and specificity of reinnervation of the regenerated neuron, the conformity among the electrophysiological and functional recovery of extraocular muscles, and neural regeneration, and that the function of extraocular muscles recovered slower than electrophysiology. Thus, we speculated that electrostimulation on the injured oculomotor nerve produced a marked effect on all phases of neural regeneration including neuronal survival, sprout formation, axonal elongation, target reconnection, and synaptogenesis. We think that neural electrostimulation can be used in oculomotor nerve injury.
- Preservation of the smooth muscular internal (vesical) sphincter and of the proximal urethra during retropubic radical prostatectomy: A technical modification to improve the early recovery of continence. [Journal Article]
- Arch Ital Urol Androl 2014 Jun; 86(2):132-4.
Objective:We describe our technique for preservation of the smooth muscular internal (vesical) sphincter and proximal urethra during radical retropubic prostatectomy (RRP) and present our preliminary clinical results. Materials and methods: The first steps of the prostatectomy reflect the standard RRP, while for the final phases the procedure continues in an anterograde manner with incision of the fibers of the detrusor muscle at the insertion of the ventral surface of the base of the prostate. At this level, the inner circular muscle of the bladder neck forms a sphincteric ring of smooth muscle that covers the longitudinally oriented smooth muscle component of the urethral musculature that extends distally to the verumontanum. These two proximal structures represent the internal sphincter that envelops and locks the proximal urethra. A blunt dissection is continued until the ring shaped vesical sphincter is separated from the prostate and the longitudinally oriented smooth muscle component of the urethral musculature is identified. The base of the prostate is then gently separated from the urethra and from the bladder until the maximal length of the urethral musculature is isolated and preserved.
Results:After 30 initial set-up procedures, 40 consecutive patients with organ confined prostate cancer were submitted to radical retropubic prostatectomy with the preservation of muscular internal sphincter and the proximal urethra and compared to 40 patients submitted to standard procedure who served as control group. The group of patients submitted to our technical modification had a faster recovery of early continence than control group at 3 and 7 days.
Conclusions:The described technique is a feasible and safe method for preservation of the internal urethral sphincter and allows improving the early recovery of urinary continence. The technique does not increase the rate of positive margins and the duration of the procedure.
- Current and Emerging Treatment Options for Fecal Incontinence. [JOURNAL ARTICLE]
- J Clin Gastroenterol 2014 Jul 10.
Fecal incontinence (FI) is a multifactorial disorder that imposes considerable social and economic burdens. The aim of this article is to provide an overview of current and emerging treatment options for FI. A MEDLINE search was conducted for English-language articles related to FI prevalence, etiology, diagnosis, and treatment published from January 1, 1990 through June 1, 2013. The search was extended to unpublished trials on ClinicalTrials.gov and relevant publications cited in included articles. Conservative approaches, including dietary modifications, medications, muscle-strengthening exercises, and biofeedback, have been shown to provide short-term benefits. Transcutaneous electrical stimulation was considered ineffective in a randomized clinical trial. Unlike initial studies, sacral nerve stimulation has shown reasonable short-term effectiveness and some complications. Dynamic graciloplasty and artificial sphincter and bowel devices lack randomized controlled trials and have shown inconsistent results and high rates of explantation. Of injectable bulking agents, dextranomer microspheres in non-animal stabilized hyaluronic acid (NASHA Dx) has shown significant improvement in incontinence scores and frequency of incontinence episodes, with generally mild adverse effects. For the treatment of FI, conservative measures and biofeedback therapy are modestly effective. When conservative therapies are ineffective, invasive procedures, including sacral nerve stimulation, may be considered, but they are associated with complications and lack randomized, controlled trials. Bulking agents may be an appropriate alternative therapy to consider before more aggressive therapies in patients who fail conservative therapies.This is an open access article distributed under the Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0, where it is permissible to download, share and reproduce the work in any medium, provided it is properly cited. The work cannot be changed in any way or used commercially. http://creativecommons.org/licenses/by-nc-nd/3.0.
- Outcome After Anal Intra-Sphincteric BoTox Injection in Children with Surgically Treated Hirschsprung's Disease. [JOURNAL ARTICLE]
- J Pediatr Gastroenterol Nutr 2014 Jul 2.
A non-relaxing internal anal sphincter is present in a relatively large proportion of children with surgically treated Hirschsprung's disease (HD) and can cause of obstructive gastro-intestinal symptoms. The short- and long-term outcome and adverse effects of intrasphincteric botulinum toxin (BoTox) injections in children with obstruction after surgically treated HD are evaluated.The outcome of children with operated HD treated with intrasphincteric BoTox injections for obstructive symptoms was analyzed with a retrospective chart review between 2002-2013 in the University Medical Centers of Maastricht and Nijmegen.Thirty-three patients were included. The median time of follow-up was 7,3 years (range 1-24). A median of 2 (range 1-5) injections were given. Initial improvement was achieved in 76% with a median duration of 4,1 months (range 1,7-58,8). Proportion of children hospitalized for enterocolitis decreased after treatment from 19 to 7. A good long-term response was found in 49%. Two children experienced complications: transient pelvic muscle paresis with impairment of walking. In both children symptoms resolved within 4 months without treatment.Intrasphincteric BoTox injections in surgically treated HD is an effective long-term therapy in approximately half of our patients with obstructive symptoms. The possibility of adverse effects should be noticed.
- The Enteric Nervous System and Gastrointestinal Innervation: Integrated Local and Central Control. [JOURNAL ARTICLE]
- Adv Exp Med Biol 2014.:39-71.
The digestive system is innervated through its connections with the central nervous system (CNS) and by the enteric nervous system (ENS) within the wall of the gastrointestinal tract. The ENS works in concert with CNS reflex and command centers and with neural pathways that pass through sympathetic ganglia to control digestive function. There is bidirectional information flow between the ENS and CNS and between the ENS and sympathetic prevertebral ganglia.The ENS in human contains 200-600 million neurons, distributed in many thousands of small ganglia, the great majority of which are found in two plexuses, the myenteric and submucosal plexuses. The myenteric plexus forms a continuous network that extends from the upper esophagus to the internal anal sphincter. Submucosal ganglia and connecting fiber bundles form plexuses in the small and large intestines, but not in the stomach and esophagus. The connections between the ENS and CNS are carried by the vagus and pelvic nerves and sympathetic pathways. Neurons also project from the ENS to prevertebral ganglia, the gallbladder, pancreas and trachea.The relative roles of the ENS and CNS differ considerably along the digestive tract. Movements of the striated muscle esophagus are determined by neural pattern generators in the CNS. Likewise the CNS has a major role in monitoring the state of the stomach and, in turn, controlling its contractile activity and acid secretion, through vago-vagal reflexes. In contrast, the ENS in the small intestine and colon contains full reflex circuits, including sensory neurons, interneurons and several classes of motor neuron, through which muscle activity, transmucosal fluid fluxes, local blood flow and other functions are controlled. The CNS has control of defecation, via the defecation centers in the lumbosacral spinal cord. The importance of the ENS is emphasized by the life-threatening effects of some ENS neuropathies. By contrast, removal of vagal or sympathetic connections with the gastrointestinal tract has minor effects on GI function. Voluntary control of defecation is exerted through pelvic connections, but cutting these connections is not life-threatening and other functions are little affected.
- Myo-architectural and Functional Alterations in Rabbit External Anal Sphincter Muscle Following Experimental Surgical Trauma. [JOURNAL ARTICLE]
- Am J Physiol Gastrointest Liver Physiol 2014 Jul 3.
Obstetrical trauma to external anal sphincter (EAS) is extremely common; however its role in the development of anal incontinence is not clear. We examined the regenerative process and functional impact of experimental surgical trauma to EAS muscle in an animal model. Surgical myotomy, a cranio-caudal incision extending along the entire length and thickness of the EAS, was performed in rabbits. Animals were allowed to recover, and anal pressures were recorded at weekly intervals for 12 weeks, using a custom designed probe system to determine the length-tension property of EAS muscle. Animals were sacrificed at pre-determined time intervals, and the anal canal was harvested for histochemical studies (for determination of muscle/connective tissue/collagen) and sarcomere length measurement. In addition, magnetic resonance diffusion tensor imaging (MR- DTI) and fiber tracking was performed to determine myoarchitectural changes in the EAS. Myotomy of the EAS muscle resulted in significant impairment of its length-tension property that showed only partial recovery during the 12-week study period. Histology revealed marked increase in the fibrosis (connective tissue = 69 % following myotomy vs 28% in controls) at 3 weeks, which persisted at 12 weeks. Immuno-staining studies confirmed deposition of collagen in the fibrotic tissue. There was no change in the sarcomere length following myotomy. MR-DTI studies revealed disorganized muscle fiber orientation in the regenerating muscle.
- Long-term recording of external urethral sphincter EMG activity in unanesthetized unrestrained rats. [JOURNAL ARTICLE]
- Am J Physiol Renal Physiol 2014 Jul 2.
The external urethral sphincter muscle (EUS) plays an important role in urinary function and often contributes to urinary dysfunction. EUS study would benefit from methodology for longitudinal recording of electromyographic activity (EMG) in unanesthetized animals, but this muscle is a poor substrate for chronic intramuscular electrodes, and thus the required methodology has not been available. We describe a method for long-term recording of EUS EMG by implantation of fine wires adjacent to the EUS that are secured to the pubic bone. Wires pass subcutaneously to a skull-mounted plug and connect to the recording apparatus by a flexible cable attached to a commutator. A force transducer-mounted cup under a metabolic cage collected urine, allowing recording of EUS EMG and voided urine weight without anesthesia or restraint. Implant durability permitted EUS EMG recording during repeated (up to 3x weekly) 24-hour sessions for more than eight weeks. EMG and voiding properties were stable over weeks 2-8. The degree of EUS phasic activity (bursting) during voiding was highly variable, with an average of 25% of voids not exhibiting bursting. Electrode implantation adjacent to the EUS yielded stable EMG recordings over extended periods and eliminated the confounding effects of anesthesia, physical restraint, and the potential for dislodgment of the chronically implanted intramuscular electrodes. These results show that micturition in unanesthetized unrestrained rats is usually, but not always associated with EUS bursting. This methodology is applicable to studying EUS behavior during progression of gradually evolving disease and injury models and in response to therapeutic interventions.