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Muscle Bundles (muscle + bundle)
Kinds of Muscle Bundles Selected AbstractsLarge Apical Muscular Ventricular Septal Defect: Asymptomatic due to Anomalous Muscle Bundles in the Right VentricleCONGENITAL HEART DISEASE, Issue 1 2007Anant Khositseth MD ABSTRACT This case report demonstrated an apical muscular ventricular septal defect (VSD) that was a large defect but behaved like a small defect because of the restrictive flow across the anomalous muscle bundles in the right ventricular (RV) apex. The anomalous muscle bundles separated the RV sinus into two parts: the RV apex connecting with the left ventricle through the apical muscular VSD on one side, and the rest of the RV sinus connecting with RV inflow and RV outflow on the other side. These findings explained why the 11-year-old girl in this study remained asymptomatic without evidence of volume load. Thus far, it was not necessary to close her defect because of the hemodynamic insignificance. [source] Positional relationships between the masticatory muscles and their innervating nerves with special reference to the lateral pterygoid and the midmedial and discotemporal muscle bundles of temporalisJOURNAL OF ANATOMY, Issue 2 2000KEIICHI AKITA For an accurate assessment of jaw movement, it is crucial to understand the comprehensive formation of the masticatory muscles with special reference to the relationship to the disc of the temporomandibular joint. Detailed dissection was performed on 26 head halves of 14 Japanese cadavers in order to obtain precise anatomical information of the positional relationships between the masticatory muscles and the branches of the mandibular nerve. After complete removal of the bony elements, the midmedial muscle bundle in all specimens and the discotemporal muscle bundle in 6 specimens, derivatives of the temporalis, which insert into the disc were observed. On the anterior area of the articular capsule and the disc of the temporomandibular joint, the upper head of the lateral pterygoid, the midmedial muscle bundle of temporalis and the discotemporal bundle of temporalis were attached mediolaterally, and in 3 specimens the posterosuperior margin of the zygomaticomandibularis was attached to the anterolateral area of the disc. It is suggested that these muscles and muscle bundles contribute to various mandibular movements. Although various patterns of the positional relationships between the muscles and muscle bundles and the their innervating nerves are observed in the present study, relative positional relationships of the muscles and muscle bundles and of nerves of the mandibular nerve are consistent. A possible scheme of the developmental formation of the masticatory muscles based on the findings of the positional relationships between the muscles and the nerves is presented. [source] Computed tomographic measurements of thigh muscle cross-sectional area and attenuation coefficient predict hip fracture: The health, aging, and body composition studyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 3 2010Thomas Lang Abstract Fatty infiltration of muscle, myosteatosis, increases with age and results in reduced muscle strength and function and increased fall risk. However, it is unknown if increased fatty infiltration of muscle predisposes to hip fracture. We measured the mean Hounsfield unit (HU) of the lean tissue within the midthigh muscle bundle (thigh muscle HU, an indicator of intramuscular fat), its cross-sectional area (CSA, a measure of muscle mass) by computed tomography (CT), bone mineral density (BMD) of the hip and total-body percent fat by dual X-ray absorptiometry (DXA), isokinetic leg extensor strength, and the Short Physical Performance Battery (SPPB) in 2941 white and black women and men aged 70 to 79 years. Sixty-three hip fractures were validated during 6.6 years of follow-up. Proportional hazards regression analysis was used to assess the relative risk (RR) of hip fracture across variations in thigh muscle attenuation, CSA, muscle strength, and physical function for hip fracture. In models adjusted by age, race, gender, body mass index, and percentage fat, decreased thigh muscle HU resulted in increased risk of hip fracture [RR/SD,=,1.58; 95% confidence interval (CI) 1.10,1.99], an association that continued to be significant after further adjustment for BMD. In models additionally adjusted by CSA, muscle strength, and SPPB score, decreased thigh muscle HU but none of the other muscle parameters continued to be associated with an increased risk of hip fracture (RR/SD,=,1.42; 95% CI 1.03,1.97). Decreased thigh muscle HU, a measure of fatty infiltration of muscle, is associated with increased risk of hip fracture and appears to account for the association between reduced muscle strength, physical performance, and muscle mass and risk of hip fracture. This characteristic captures a physical characteristic of muscle tissue that may have importance in hip fracture etiology. © 2010 American Society for Bone and Mineral Research [source] The Results of Probe Technique for Transatrial Repair of Tetralogy of FallotJOURNAL OF CARDIAC SURGERY, Issue 6 2002Ahmet Turan Yilmaz M.D. The most critical point in transatrial repair of TOF is infundibular dissection. Right atrial approach provides better surgical exposure for parietal extension of the infundibular septum when compared to a right ventricular approach. However, it is not always easy to determine the localization and amount of muscle bundles to be resected and this surgical maneuver requires experience. Methods: Nineteen patients were reviewed who had repair of isolated TOF by this technique from 1993 to 2001. The mean age of patients was 5 ± 2 years . Transatrial-transpulmonary approach was performed for all patients. To make the infundibular muscle-bundle resection easier and to determine the localization and amount of muscle bundle to be resected, we placed a Hegar dilator into the right ventricle through pulmonary arteriotomy. The muscle bundles between the dilator and the anterior leaflet annulus of the tricuspid valve were totally excised until the intraventricular part of the dilator and pulmonary annulus became completely visible. The area between the Hegar dilator and the margins of the ventricular septal defect (VSD) was left untouched. None of the patients had transannular patch. Tricuspid valve detachment in order to improve the exposure was done in 11 patients. All patients were followed up in our clinic at regular six-month intervals by echocardiography. Results: There was no early or late mortality nor reoperation for residual VSD or residual right ventricle (RV) outflow obstruction. All patients were in NYHA class I. RV on the echocardiography was spared late dilatation and had a good late functional status. Eighteen patients had no or mild pulmonary regurgitation. One patient who had undergone tricuspid anterior leaflet detachment showed mild tricuspid insufficiency. Conclusions: On the basis of hemodynamic outcomes, this procedure for elective repair of TOF in selected cases gives excellent early and mid-term results.(J Card Surg 2002;17:490-494) [source] Origin and propagation of spontaneous excitation in smooth muscle of the guinea-pig urinary bladderTHE JOURNAL OF PHYSIOLOGY, Issue 2 2001Hikaru Hashitani 1The origin and propagation of waves of spontaneous excitation in bundles of smooth muscle of the guinea-pig bladder were examined using intracellular recording techniques and visualization of the changes in the intracellular calcium concentration ([Ca2+]i). 2Bladder smooth muscle cells exhibited spontaneous transient increases in [Ca2+]i which originated along a boundary of each smooth muscle bundle and then spread to the other boundary with a conduction velocity of 2.0 mm s,1. 3Spontaneous increases in [Ca2+]i were always preceded by action potentials. Nifedipine (10 ,M) abolished increases in both [Ca2+]i and action potentials. Caffeine (10 mM), ryanodine (50 ,M) and cyclopiazonic acid (10 ,M) reduced the amplitude of the associated increases in [Ca2+]i without preventing the generation of action potentials. 4Spontaneous action potentials had conduction velocities of 40 mm s,1 in the axial direction and 1.3 mm s,1 in the transverse direction. The electrical length constants of the bundles of muscle were 425 ,m in the axial direction and 12.5 ,m in the transverse direction. 5Neurobiotin, injected into an impaled smooth muscle cell, spread more readily to neighbouring cells located in the axial direction than those located in the transverse direction. The spread of neurobiotin was inhibited by 18,-glycyrrhetinic acid (18,-GA, 40 ,M), a gap junction blocker. 6Immunohistochemistry for Connexin 43 showed abundant punctate staining on the smooth muscle cell membranes. 7These results suggested that spontaneous action potentials and associated calcium waves occur almost simultaneously along the boundary of bladder smooth muscle bundles and then propagate to the other boundary probably through gap junctions. [source] Innervation of the detrusor muscle bundle in neurogenic detrusor overactivityBJU INTERNATIONAL, Issue 7 2003M.J. Drake OBJECTIVE To evaluate the peripheral anatomical distribution of innervation within muscle bundles of the detrusor and the changes arising in neurogenic detrusor overactivity (DO). PATIENTS AND METHODS Full-thickness samples from the bladder dome of three cadaveric transplant organ donors and four people with neurogenic DO caused by spinal cord injury were compared. Systematic serial cryostat sections were stained using Masson trichrome and elastin techniques, and vimentin immunohistochemistry. A coherent image stack was generated for three-dimensional image reconstructions, which were displayed using mixed rendering (i.e. differing graphics for separate tissue components) to show peri- and intra-bundle innervation against the muscle fascicle framework. RESULTS Control specimens had a dense nerve supply. Muscle bundle innervation was derived by dichotomous branching from peri-bundle nerve trunks in the inter-bundle connective tissue. Transverse interfascicular branches entered bundles perpendicular to the long axis at the midpoint of the bundle. They gave rise to axial interfascicular branches, which distributed to the pre-terminal and terminal nerve fibres. All samples from patients with neurogenic DO had patchy denervation. The primary deficit was predominantly at the level of the terminal axial innervation and was cross-sectionally consistent along the longitudinal axis of the muscle bundle. CONCLUSION Patchy denervation may reflect a deficit at the level of the peripheral ganglia. Any contraction in the areas of denervation either occurs out of co-ordination with the rest of the bladder, or is co-ordinated by means of non-neural structures. The observation of fine muscle strands running between fascicles, and connective tissue anchoring structures, represent two hypothetical mechanisms by which such co-ordination might be effected. [source] An anatomical study of the muscles that attach to the articular disc of the temporomandibular jointCLINICAL ANATOMY, Issue 8 2009Kosuke Matsunaga Abstract The masticatory muscles are generally described as the muscles that originate from the cranium and insert on the mandible. Some of the masticatory muscles also insert into the articular disc of the temporomandibular joint. Although there are numerous reports of studies on the attachment of the fibers to the disc, most reports discuss only one muscle. We have shown that the masticatory muscles are not simply a group of clearly independent muscles, but that these muscles contain various transitional muscle bundles among the major muscles. From this point of view, we carried out minute dissection of the collective muscles and muscle bundles surrounding the temporomandibular joint. We dissected 40 head halves of 20 Japanese cadavers (10 males, 10 females: average 79.6 yr). After complete removal of the bony elements, the structures surrounding the temporomandibular joint were investigated en-block. In all specimens, the superior surface of the upper head of lateral pterygoid and the midmedial muscle bundle were attached to the disc. In some specimens, the discotemporal bundle, zygomaticomandibularis, and masseter were attached to the anterior surface of the disc. The total vector of these muscles pulls the disc anteriorly. In contrast, the vector of the muscles to the condylar processes of the mandible pulls the mandible medially. From these observations, it seems that the fibers, which attach to the disc act to steady the disc against the masticatory movement. Clin. Anat. 22:932,940, 2009. © 2009 Wiley-Liss, Inc. [source] Large Apical Muscular Ventricular Septal Defect: Asymptomatic due to Anomalous Muscle Bundles in the Right VentricleCONGENITAL HEART DISEASE, Issue 1 2007Anant Khositseth MD ABSTRACT This case report demonstrated an apical muscular ventricular septal defect (VSD) that was a large defect but behaved like a small defect because of the restrictive flow across the anomalous muscle bundles in the right ventricular (RV) apex. The anomalous muscle bundles separated the RV sinus into two parts: the RV apex connecting with the left ventricle through the apical muscular VSD on one side, and the rest of the RV sinus connecting with RV inflow and RV outflow on the other side. These findings explained why the 11-year-old girl in this study remained asymptomatic without evidence of volume load. Thus far, it was not necessary to close her defect because of the hemodynamic insignificance. [source] Angioleiomyoma: a clinical, pathological and radiological reviewINTERNATIONAL JOURNAL OF CLINICAL PRACTICE, Issue 6 2004P. Ramesh Summary Angioleiomyoma is a benign tumour arising from the vascular smooth muscle (tunica media) and presents commonly between third and fifth decades of life. Although there are sporadic reports about this tumour in the literature, none describes all the information in detail. This review is an attempt to collate all the facts in one concise article. Angioleiomyoma presents as a painful mass in approximately 60% of the cases. One of the distinct clinical feature noted is the increase in size of the swelling with physical activity of the involved part, especially in the hand. It should be considered in the differential diagnosis of painful nodular lesions of the extremity. Pre-operative diagnosis is difficult, but with a high index of suspicion and awareness, it is possible. The use of ultrasound and magnetic resonance imaging should be considered. It causes minimal morbidity and excision is usually curative. Histological examination using smooth muscle Actin stain portraits the smooth muscle bundles clearly. [source] Histology of the fetal prune belly syndrome with reference to the efficacy of prenatal decompressionINTERNATIONAL JOURNAL OF UROLOGY, Issue 5 2000Kenji Shimada Abstract Background: Deficient abdominal musculature, complex abnormalities of urinary tracts and bilateral abdominal cryptorchidism represent the basic characteristics of prune belly syndrome (PBS). Although prenatal diagnosis of PBS is rarely made, because of the wide variety of ultrasonographic images, reported cases have gradually increased. Once a fetus suspected of having PBS is found, it is sometimes difficult for the pediatric urologists to decide how to treat them. The histology of the kidney and urinary tracts in fetuses with PBS was reviewed in order to give suggestions on the management of prenatal cases. Methods: Autopsy records of nine fetuses (5 males, 2 females and 2 undetermined) with characteristically distended and deficient abdominal wall were reviewed. Gestational age (GA) at detection ranged from 12 to 25 weeks and at delivery from 13 to 32 weeks. Results: Renal histology in two fetuses showed earlier than normal disappearance of cortical nephrogenic zone replaced by cortical cysts and dysplastic structures. The nephrogenic zone was retained in five fetuses which were younger than GA 20 weeks. While the number of glomeruli along the medullary ray was normal for the age in three fetuses younger than GA 20 weeks, it was decreased in all others. Bladder histology was variable showing both increased musculature and defective or dysplastic muscles. There was a tendency for connective tissues in the bladder wall to increase in proportion to GA, The ureter revealed scarcity of muscle bundles among dense connective tissue. The urethra was atretic in eight fetuses. Conclusion: The clinical implication from the renal histology is that decompression of the urinary tract should be done before GA 20 weeks. However, the early fetal treatment appears to have no effect on the urodynamics in this disorder with deficient musculature. [source] Positional relationships between the masticatory muscles and their innervating nerves with special reference to the lateral pterygoid and the midmedial and discotemporal muscle bundles of temporalisJOURNAL OF ANATOMY, Issue 2 2000KEIICHI AKITA For an accurate assessment of jaw movement, it is crucial to understand the comprehensive formation of the masticatory muscles with special reference to the relationship to the disc of the temporomandibular joint. Detailed dissection was performed on 26 head halves of 14 Japanese cadavers in order to obtain precise anatomical information of the positional relationships between the masticatory muscles and the branches of the mandibular nerve. After complete removal of the bony elements, the midmedial muscle bundle in all specimens and the discotemporal muscle bundle in 6 specimens, derivatives of the temporalis, which insert into the disc were observed. On the anterior area of the articular capsule and the disc of the temporomandibular joint, the upper head of the lateral pterygoid, the midmedial muscle bundle of temporalis and the discotemporal bundle of temporalis were attached mediolaterally, and in 3 specimens the posterosuperior margin of the zygomaticomandibularis was attached to the anterolateral area of the disc. It is suggested that these muscles and muscle bundles contribute to various mandibular movements. Although various patterns of the positional relationships between the muscles and muscle bundles and the their innervating nerves are observed in the present study, relative positional relationships of the muscles and muscle bundles and of nerves of the mandibular nerve are consistent. A possible scheme of the developmental formation of the masticatory muscles based on the findings of the positional relationships between the muscles and the nerves is presented. [source] The Results of Probe Technique for Transatrial Repair of Tetralogy of FallotJOURNAL OF CARDIAC SURGERY, Issue 6 2002Ahmet Turan Yilmaz M.D. The most critical point in transatrial repair of TOF is infundibular dissection. Right atrial approach provides better surgical exposure for parietal extension of the infundibular septum when compared to a right ventricular approach. However, it is not always easy to determine the localization and amount of muscle bundles to be resected and this surgical maneuver requires experience. Methods: Nineteen patients were reviewed who had repair of isolated TOF by this technique from 1993 to 2001. The mean age of patients was 5 ± 2 years . Transatrial-transpulmonary approach was performed for all patients. To make the infundibular muscle-bundle resection easier and to determine the localization and amount of muscle bundle to be resected, we placed a Hegar dilator into the right ventricle through pulmonary arteriotomy. The muscle bundles between the dilator and the anterior leaflet annulus of the tricuspid valve were totally excised until the intraventricular part of the dilator and pulmonary annulus became completely visible. The area between the Hegar dilator and the margins of the ventricular septal defect (VSD) was left untouched. None of the patients had transannular patch. Tricuspid valve detachment in order to improve the exposure was done in 11 patients. All patients were followed up in our clinic at regular six-month intervals by echocardiography. Results: There was no early or late mortality nor reoperation for residual VSD or residual right ventricle (RV) outflow obstruction. All patients were in NYHA class I. RV on the echocardiography was spared late dilatation and had a good late functional status. Eighteen patients had no or mild pulmonary regurgitation. One patient who had undergone tricuspid anterior leaflet detachment showed mild tricuspid insufficiency. Conclusions: On the basis of hemodynamic outcomes, this procedure for elective repair of TOF in selected cases gives excellent early and mid-term results.(J Card Surg 2002;17:490-494) [source] The Mechanisms of Atrial FibrillationJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 2006PENG-SHENG CHEN M.D. In this article we have reviewed the mechanisms of atrial fibrillation (AF) with special emphasis on the thoracic veins. Based on a number of features, the thoracic veins are highly arrhythmogenic. The pulmonary vein (PV)-left atrial (LA) junction has discontinuous myocardial fibers separated by fibrotic tissues. The PV muscle sleeve is highly anisotropic. The vein of Marshall (VOM) in humans has multiple small muscle bundles separated by fibrosis and fat. Insulated muscle fibers can promote reentrant excitation, automaticity, and triggered activity. The PV muscle sleeves contain periodic acid-Schiff (PAS)-positive large pale cells that are morphologically reminiscent of Purkinje cells. These special cells could be the sources of focal discharge. Antiarrhythmic drugs have significant effects on PV muscle sleeves both at baseline and during AF. Both class I and III drugs have effects on wavefront traveling from PV to LA and from LA to PV. Separating the thoracic veins and the LA with ablation techniques also prevents PV-LA interaction. By reducing PV-LA interaction, pharmacological therapy and PV isolation reduce the activation rate in PV, intracellular calcium accumulation, and triggered activity. Therefore, thoracic vein isolation is an important technique in AF control. We conclude that thoracic veins are important in the generation and maintenance of AF. [source] Demonstration of Electrical and Anatomic Connections Between Marshall Bundles and Left Atrium in Dogs: Implications on the Generation of P Waves on Surface ElectrocardiogramJOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 12 2002CHIKAYA OMICHI M.D. Marshall Bundle and P Wave.Introduction: The muscle bundles within the ligament of Marshall (LOM) are electrically active. The importance of these muscle bundles (Marshall bundle [MB]) to atrial activation and the generation of the ECG P wave is unclear. Methods and Results: We used optical mapping techniques to study epicardial activation patterns in isolated perfused left atrium in four dogs. In another seven dogs, P waves were studied before and after in vivo radiofrequency (RF) ablation of the connection between coronary sinus (CS) and the LOM. Computerized mapping was performed before and after RF ablation. Optical mapping studies showed that CS pacing resulted in broad wavefronts propagating from the middle and distal LOM directly to the adjacent left atrium (LA). Serial sections showed direct connection between MB and LA near the orifice of the left superior pulmonary vein in two dogs. In vivo studies showed that MB potentials were recorded in three dogs. After ablation, the duration of P waves remained unchanged. In the other four dogs, MB potentials were not recorded. Computerized mapping showed that LA wavefronts propagated to the MB region via LA-MB connection and then excited the CS. After ablation, the activation of CS muscle sleeves is delayed, and P wave duration increased from 65.3 ± 14.9 msec to 70.5 ± 17.2 msec (P = 0.025). Conclusion: In about half of the normal dogs, MB provides an electrical conduit between LA free wall and CS. Severing MB alters the atrial activation and lengthens the P wave. MB contributes to generation of the P wave on surface ECG. [source] Comparative morphology and cytology of the male sperm-transmission organs in viviparous species of clinid fishes (Clinidae: Teleostei, Perciformes)JOURNAL OF MORPHOLOGY, Issue 12 2006Lev Fishelson Abstract This work comprises the first comparative study of the morphology and cytology of the sperm transmission organs in males of 14 species of viviparous clinid fishes (Clinidae, Blennioidei, Teleostei). The form and dimensions of these organs differ among the various species studied. The organs are composed of intra-abdominal ampullae, into which the sperm ducts and urinary bladder anchor, and an external protruding intromittent papilla used for insemination. The form of the ampullae differs among the various species, from pear-shaped to horseshoe-shaped. It increases in dimensions with increasing length of the male. In all the species this organ is covered by a connective-tissue tunic that encompasses both circular and longitudinal striated muscle bundles. The lumina of the ampullae harbor the epididymis, a strongly convoluted and plicated duct, which becomes filled with spermatozeugmata during reproduction. From here, the epididymis continues into the protruding intromittent papillae, where its folds gradually straighten at the apical part of the intromittent organ. The form and dimensions of this copulatory organ also differ in the various species. Papillae bearing taste buds are found on the apical parts of the intromittent organ, and it is probable that these, together with the difference in forms of the organ, help to prevent interspecific copulation. J. Morphol., 2006. © 2006 Wiley-Liss, Inc. [source] Ultrastructural evidence for communication between intramuscular vagal mechanoreceptors and interstitial cells of Cajal in the rat fundusNEUROGASTROENTEROLOGY & MOTILITY, Issue 1 2008T. L. Powley Abstract, To assess whether afferent vagal intramuscular arrays (IMAs), putative gastrointestinal mechanoreceptors, form contacts with interstitial cells of Cajal of the intramuscular type (ICC-IM) and to describe any such contacts, electron microscopic analyses were performed on the external muscle layers of the fundus containing dextran-labelled diaminobenzidin (DAB)-stained IMAs. Special staining and embedding techniques were developed to preserve ultrastructural features. Within the muscle layers, IMA varicosities were observed in nerve bundles traversing major septa without contact with ICC-IM, contacting unlabelled neurites and glial cells. IMA varicosities were encountered in minor septa in contact with ICC-IM which were not necessarily in close contact with muscle cells. In addition, IMA varicosities were observed within muscle bundles in close contact with ICC-IM which were in gap junction contact with muscle cells. IMAs formed varicosities containing predominantly small agranular vesicles, occasionally large granular vesicles and prejunctional thickenings in apposition to ICC-IM processes, indicating communication between ICC and IMA via synapse-like contacts. Taken together, these different morphological features are consistent with a hypothesized mechanoreceptor role for IMA-ICC complexes. Intraganglionic laminar ending varicosities contacted neuronal somata and dendrites in the myenteric plexus of the fundus, but no contacts with ICC associated with Auerbach's plexus were encountered. [source] Effects of imatinib mesylate (Glivec®) as a c-kit tyrosine kinase inhibitor in the guinea-pig urinary bladderNEUROUROLOGY AND URODYNAMICS, Issue 3 2006Yasue Kubota Abstract Aims In the gastrointestinal tract, slow wave activity in smooth muscle is generated by the interstitial cells of Cajal (ICC). Detrusor smooth muscle strips of most species show spontaneous contractions which are triggered by action potential bursts, however, the pacemaker mechanisms for the detrusor are still unknown. Recently, ICC-like cells have been found in guinea-pig bladder, using antibodies to the c-kit receptor. We have investigated the effects of Glivec, a c-kit tyrosine kinase inhibitor, on spontaneous action potentials in guinea-pig detrusor and intravesical pressure of isolated guinea-pig bladders. Methods Changes in the membrane potential were measured in guinea-pig detrusor smooth muscle using conventional microelectrode techniques. Pressure changes in the bladder were recorded using whole organ bath techniques. Results Smooth muscle cells in detrusor muscle bundles exhibited spontaneous action potentials, and spontaneous pressure rises occurred in isolated bladders. Glivec (10 ,M) converted action potential bursts into continuous firing with no effects on the shape of individual action potentials. Glivec (>50 ,M) reduced the amplitude of spontaneous pressure rises in the whole bladder in a dose dependent manner and abolished spontaneous action potentials in detrusor smooth muscle cells. Conclusions The results suggest that ICC-like cells may be responsible for generating bursts of action potentials and contractions in detrusor smooth muscle. Drugs inhibiting the c-kit receptor may prove useful for treating the overactive bladder. Neurourol. Urodynam. © 2006 Wiley-Liss, Inc. [source] Contractile properties of the proximal urethra and bladder in female pig: Morphology and functionNEUROUROLOGY AND URODYNAMICS, Issue 1 2006J.J.M. Pel Abstract Aims To compare the contractile properties of proximal urethral and bladder muscle of the female pig. Materials and Methods In two proximal segments (I and II) of the urethra, small muscle bundles were excised to measure the force-length (maximum force) and the force-velocity (unloaded shortening velocity) relation using the stop-test. The rate of force development was calculated using phase plots. Contractile properties of urethral and bladder segments were statistically compared using the Mann,Whitney U -test. Immunohistochemical staining of whole circumference urethral cross sections was used to identify the location of smooth and striated muscle fibres. Results On isometric force development, the urethral muscle bundles revealed a fast (,0.5 sec) and a slow (,2.1 sec) time constant, whereas in bladder only a slow (,2.3 sec) component was measured. On average, isometric force was highest in bladder. The length range over which force was produced was smallest in urethral segment II, followed by urethral segment I and finally bladder. The unloaded shortening velocity was 0.15, 0.25 and 0.35 1/sec, respectively. Histological preparations showed that smooth as well as striated muscle was present in proximal urethra. In urethral muscle bundles, spontaneous contractions were measured with a frequency of 0.4 Hz. Conclusions Differences in contractility found between urethra and bladder may be ascribed to the presence of striated muscle in the proximal urethra. The regulation of tone and spontaneous contractions may be part of the continence mechanism in the female pig urinary tract. © 2005 Wiley-Liss, Inc. [source] Origin and propagation of spontaneous excitation in smooth muscle of the guinea-pig urinary bladderTHE JOURNAL OF PHYSIOLOGY, Issue 2 2001Hikaru Hashitani 1The origin and propagation of waves of spontaneous excitation in bundles of smooth muscle of the guinea-pig bladder were examined using intracellular recording techniques and visualization of the changes in the intracellular calcium concentration ([Ca2+]i). 2Bladder smooth muscle cells exhibited spontaneous transient increases in [Ca2+]i which originated along a boundary of each smooth muscle bundle and then spread to the other boundary with a conduction velocity of 2.0 mm s,1. 3Spontaneous increases in [Ca2+]i were always preceded by action potentials. Nifedipine (10 ,M) abolished increases in both [Ca2+]i and action potentials. Caffeine (10 mM), ryanodine (50 ,M) and cyclopiazonic acid (10 ,M) reduced the amplitude of the associated increases in [Ca2+]i without preventing the generation of action potentials. 4Spontaneous action potentials had conduction velocities of 40 mm s,1 in the axial direction and 1.3 mm s,1 in the transverse direction. The electrical length constants of the bundles of muscle were 425 ,m in the axial direction and 12.5 ,m in the transverse direction. 5Neurobiotin, injected into an impaled smooth muscle cell, spread more readily to neighbouring cells located in the axial direction than those located in the transverse direction. The spread of neurobiotin was inhibited by 18,-glycyrrhetinic acid (18,-GA, 40 ,M), a gap junction blocker. 6Immunohistochemistry for Connexin 43 showed abundant punctate staining on the smooth muscle cell membranes. 7These results suggested that spontaneous action potentials and associated calcium waves occur almost simultaneously along the boundary of bladder smooth muscle bundles and then propagate to the other boundary probably through gap junctions. [source] Cutaneous heterotopic bronchogenic tissue in the scapular areaAUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 1 2010aduman Balaban Ad ABSTRACT Cutaneous bronchogenic anomalies are very rare lesions, and most of them present as cysts and/or sinus tracts in the subcutaneous layer. We report a 15-year-old boy who presented with a crusted and papillomatous plaque over the right scapular region. Histopathological examination of this plaque revealed pseudostratified ciliated columnar epithelium with papillary invaginations that included mucinous material. The lesion had no cyst or sinus formation and was bordered with smooth muscle bundles in stroma. [source] A porcine model of bladder outlet obstruction incorporating radio-telemetered cystometryBJU INTERNATIONAL, Issue 1 2007Matthew B. Shaw OBJECTIVE To present a novel porcine model of bladder outlet obstruction (BOO) with a standardized bladder outlet resistance and real-time ambulatory radio-telemetered cystometry, as BOO is a common condition with many causes in both adults and children, with significant morbidity and occasional mortality, but attempts to model this condition in many animal models have the fundamental problem of standardising the degree of outlet resistance. MATERIALS AND METHODS BOO was created in nine castrated male pigs by dividing the mid-urethra; outflow was allowed through an implanted bladder drainage catheter containing a resistance valve, allowing urine to flow across the valve only when a set pressure differential was generated across the valve. An implantable radio-telemetered pressure sensor monitored the pressure within the bladder and abdominal cavity, and relayed this information to a remote computer. Four control pigs had an occluded bladder drainage catheter and pressure sensor placed, but were allowed to void normally through the native urethra. Intra-vesical pressure was monitored by telemetry, while the resistance valve was increased weekly, beginning with 2 cmH2O and ultimately reaching 10 cmH2O. The pigs were assessed using conventional cystometry under anaesthesia before death, and samples conserved in formalin for haematoxylin and eosin staining. RESULTS The pigs had radio-telemetered cystometry for a median of 26 days. All telemetry implants functioned well for the duration of the experiment, but one pig developed a urethral fistula and was excluded from the study. With BOO the bladder mass index (bladder mass/body mass × 10 000) increased from 9.7 to 20 (P = 0.004), with a significant degree of hypertrophy of the detrusor smooth muscle bundles. Obstructed bladders were significantly less compliant than control bladders (8.3 vs 22.1 mL/cmH2O, P = 0.03). Telemetric cystometry showed that there was no statistically significance difference in mean bladder pressure between obstructed and control pigs (4.8 vs 6.7 cmH2O, P = 0.7), but that each void was longer in the pigs with BOO. CONCLUSION This new model of BOO provides a method of reliably and precisely defining the bladder outlet resistance; it induces the changes classically seen with BOO, including increased bladder mass, increased smooth muscle bundle size and decreased compliance. [source] Innervation of the detrusor muscle bundle in neurogenic detrusor overactivityBJU INTERNATIONAL, Issue 7 2003M.J. Drake OBJECTIVE To evaluate the peripheral anatomical distribution of innervation within muscle bundles of the detrusor and the changes arising in neurogenic detrusor overactivity (DO). PATIENTS AND METHODS Full-thickness samples from the bladder dome of three cadaveric transplant organ donors and four people with neurogenic DO caused by spinal cord injury were compared. Systematic serial cryostat sections were stained using Masson trichrome and elastin techniques, and vimentin immunohistochemistry. A coherent image stack was generated for three-dimensional image reconstructions, which were displayed using mixed rendering (i.e. differing graphics for separate tissue components) to show peri- and intra-bundle innervation against the muscle fascicle framework. RESULTS Control specimens had a dense nerve supply. Muscle bundle innervation was derived by dichotomous branching from peri-bundle nerve trunks in the inter-bundle connective tissue. Transverse interfascicular branches entered bundles perpendicular to the long axis at the midpoint of the bundle. They gave rise to axial interfascicular branches, which distributed to the pre-terminal and terminal nerve fibres. All samples from patients with neurogenic DO had patchy denervation. The primary deficit was predominantly at the level of the terminal axial innervation and was cross-sectionally consistent along the longitudinal axis of the muscle bundle. CONCLUSION Patchy denervation may reflect a deficit at the level of the peripheral ganglia. Any contraction in the areas of denervation either occurs out of co-ordination with the rest of the bladder, or is co-ordinated by means of non-neural structures. The observation of fine muscle strands running between fascicles, and connective tissue anchoring structures, represent two hypothetical mechanisms by which such co-ordination might be effected. [source] An anatomical study of the muscles that attach to the articular disc of the temporomandibular jointCLINICAL ANATOMY, Issue 8 2009Kosuke Matsunaga Abstract The masticatory muscles are generally described as the muscles that originate from the cranium and insert on the mandible. Some of the masticatory muscles also insert into the articular disc of the temporomandibular joint. Although there are numerous reports of studies on the attachment of the fibers to the disc, most reports discuss only one muscle. We have shown that the masticatory muscles are not simply a group of clearly independent muscles, but that these muscles contain various transitional muscle bundles among the major muscles. From this point of view, we carried out minute dissection of the collective muscles and muscle bundles surrounding the temporomandibular joint. We dissected 40 head halves of 20 Japanese cadavers (10 males, 10 females: average 79.6 yr). After complete removal of the bony elements, the structures surrounding the temporomandibular joint were investigated en-block. In all specimens, the superior surface of the upper head of lateral pterygoid and the midmedial muscle bundle were attached to the disc. In some specimens, the discotemporal bundle, zygomaticomandibularis, and masseter were attached to the anterior surface of the disc. The total vector of these muscles pulls the disc anteriorly. In contrast, the vector of the muscles to the condylar processes of the mandible pulls the mandible medially. From these observations, it seems that the fibers, which attach to the disc act to steady the disc against the masticatory movement. Clin. Anat. 22:932,940, 2009. © 2009 Wiley-Liss, Inc. [source] Transverse carpal muscle in association with carpal tunnel syndrome: Report of three casesCLINICAL ANATOMY, Issue 4 2005Dogan Tuncali Abstract Anomalous muscles of the upper extremity are common, however, symptomatic anomalies causing CTS are rare. Three cases of CTS that are believed to be caused by an anomalous muscle located palmar to the transverse carpal ligament with transversely oriented muscle bundles is presented. Despite the arguments in literature, this is certainly an anomalous muscle that can be encountered during carpal tunnel release and be problematic to manipulate when minimally invasive approaches are chosen. Clin. Anat. 18:308,312, 2005. © 2005 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||