Striated Muscle Layer Research Articles

A Case of Adenocarcinoma of the External Nose

Adenocarcinoma occurs very rarely in the paranasal sinuses; moreover, adenocarcinoma diagnosed in the external nose is rarely reported. A 58-year-old male patient visited our hospital with an enlarged right nasal mass. On image studies, a 1.5 cm sized mass was found on the right nasolabial fold, which was surgically removed via sublabial approach. Intraoperative frozen section examination showed inflammatory tissue without tumor cells. However, adenocarcinoma showing infiltration between the skeletal muscle layers was diagnosed on the final histopathologic examination after surgery. In the immunohistochemical staining test, CK7 positive, CK20 negative, and GCDFP-15 positive were confirmed, so metastasis of adenocarcinoma was considered first rather than primary cancer of the nasolabial fold. There was no recurrence and no tumor development in other sites after postoperative chemoradiation therapy of 32 months.

Microscopic anatomy of the oesophagus in the southern white-breasted hedgehog (Erinaceus concolor) a histochemical, stereological, and scanning electron microscope study.

The present work was designed to investigate the microscopic structure of the oesophagus in the southern white-breasted hedgehog (Erinaceus concolor) using histochemical staining, Scanning electron microscope (SEM), and stereological procedures. Four adult males were included in our study. Serial sections of the entire length of the oesophagus were stained with aldehyde fuchsin, alcian blue (pH2.5), Periodic acid Schiff (PAS), and Masson's trichrome. Then, the total volume of the oesophagus, and the total volume of its different layers, were estimated using Cavalieri's principle. The oesophageal epithelium was a non-keratinized stratified squamous type. Muscularis mucosa was present as a thick layer between lamina propria and submucosa and its thickness was increased toward the stomach. Tunica submucosa was a loose connective tissue containing an oesophageal gland with PAS-positive and AB-positive reactions throughout the submucosa and become denser toward the stomach. The tunica muscularis consisted of two distinct striated muscle layers, and its thickness was decreased toward the stomach. On SEM images, the cervical and thoracic oesophagus showed shallow folding, while the abdominal part had deeper folds. The present findings indicate that the histological properties of the oesophagus in southern white-breasted hedgehogs have slight similarities with rodents and considering its epithelium, submucosal glands and tunica muscularis more resemble with dog oesophagus. The obtained results may be quite helpful to improve the current knowledge of the histophysiology of the hedgehog gastrointestinal tract as a member of eulipotyplan mammals and as a pet for biologists and veterinarians.

Model‐based analysis of microcirculatory parameters affecting O 2 transport in skeletal muscle subjected to fixed surface PO 2

Microcirculation in skeletal muscle determines both blood flow distribution and O2 transport. The partial pressure of oxygen (PO2) is a prime candidate to assess in tissue, as PO2 variations herald a functionality decline in skeletal muscle. Traditional non-invasive microcirculatory techniques such as Intra-vital Video Microscopy (IVVM) allowing for blood velocity and capillary saturation (SO2) measurements, are unable to directly assess skeletal muscle tissue PO2. Instead, modern microcirculatory O2 analysis relies on biophysical models to recreate tissue PO2 distributions. (Ellis et al, Microcirc 2012, 19:5). Recently, a continuous coupled partial differential equation (PDE) model of two layers of skeletal muscle coupled via diffusion at their boundaries was developed accounting for tissue O2 diffusion, capillary O2 convection, tissue O2 consumption, and capillary-tissue O2 transfer. This model was developed to study an IVVM protocol involving a controlled exposure of skeletal muscle using an O2 exchange chamber. In the protocol studied, hemodynamic parameters in the skeletal muscle region near to the O2 chamber are experimentally shown to exhibit substantial variations. The prevailing theory is capillary perfusion limits the depth of penetration of the chamber O2, and local hemodynamic parameter responses serve to regulate capillary SO2 in skeletal muscle; this would be towards either a fixed target value or homogeneity with neighboring capillary modules. The coupled PDE two-layer model was developed for steady-state PO2 distributions and was solved using traditional math techniques such as operator decoupling and Fourier decomposition, and exhibited the ability to rapidly and accurately calculate PO2 distributions in skeletal muscle which agreed with experimental values. (Afas and Goldman, Vasc Bio 2020). The solution affords for the unique ability not allowed in previous convection-diffusion analytic models of O2 transport, to observe the interaction of both skeletal muscle layers. This is achieved by assuming baseline hemodynamic parameters in the layer far from the O2 chamber and allowing the near layer to take on a range of parameter variations; these variations can be compared to experimental observations. In this study, the behavior of both layers of skeletal muscle adjacent to an O2 chamber will be modelled by the a-priori fixing of parameters in the region far from the O2 chamber and allowing near-layer parameters to be perturbed. Several parameters, including capillary density φ, velocity vB, inlet saturation SIN, hematocrit HT, and tissue consumption μ will have this variation method applied from previous baselines (Afas et al, Math Biosci 2021, in press), and the resultant two-layer O2 profiles will be visualized, as well as the conditions under which the capillary SO2 is homogenized in both layers of skeletal muscle.

Laryngeal Reconstruction Using Tissue-Engineered Implants in Pigs: A Pilot Study.

There are currently no treatments available that restore dynamic laryngeal function after hemilaryngectomy. We have shown that dynamic function can be restored post hemilaryngectomy in a rat model. Here, we report in a first of its kind, proof of concept study that this previously published technique is scalable to a porcine model. Animal study. Muscle and fat biopsies were taken from three Yucatan minipigs. Muscle progenitor cells (MPCs) and adipose stem cells (ASCs) were isolated and cultured for 3 weeks. The minipigs underwent a left laterovertical partial laryngectomy sparing the left arytenoid cartilage and transecting the recurrent laryngeal nerve. Each layer was replaced with a tissue-engineered implant: 1) an acellular mucosal layer composed of densified Type I oligomeric collagen, 2) a skeletal muscle layer composed of autologous MPCs and aligned oligomeric collagen differentiated and induced to express motor endplates (MEE), and 3) a cartilage layer composed of autologous ASCs and densified oligomeric collagen differentiated to cartilage. Healing was monitored at 2 and 4 weeks post-op, and at the 8 week study endpoint. Animals demonstrated appropriate weight gain, no aspiration events, and audible phonation. Video laryngoscopy showed progressive healing with vascularization and re-epithelialization present at 4 weeks. On histology, there was no immune reaction to the implants and there was complete integration into host tissue with nerve and vascular ingrowth. This pilot study represents a first in which a transmural vertical partial laryngectomy was performed and successfully repaired with a customized, autologous stem cell-derived multi-layered tissue-engineered implant. NA Laryngoscope, 131:2277-2284, 2021.

Application of adipose‐derived, muscle‐derived, and co‐cultured stem cells for the treatment of stress urinary incontinence in rat models

Based on the recent advancements in cell therapy techniques, we aimed to evaluate the efficacy of transurethral injection of autologous adipose-derived stem cells, muscle-derived stem cells, and co-cultured cells for the rehabilitation of stress urinary incontinence rat models. We hypothesized that the utilization of co-cultured stem cells could result in enhanced therapeutic outcomes attributed to their more comprehensive environment of paracrine factors and cytokines. We performed bilateral pudendal nerve transection surgeries to simulate urinary incontinence in 25 female Wistar rats and employed urodynamic evaluations to confirm the injury. We autologously isolated and cultured adipose-derived mesenchymal stem cells, muscle-derived stem cells, and a mixed culture of the two types, which we subsequently injected into the urethral lumen of the damaged animals. Three weeks after the injection, urodynamic assays, histological staining, and immunohistochemical evaluations were performed to determine the efficacy of the implanted cell cultures in sphincter function improvements or structural modifications. Histological evaluations suggested a regenerative process in the muscular layer of the external sphincter 3 weeks after the injection. Also, immunohistochemical analysis revealed a thickened periurethral striated muscle layer in the co-cultured group. Postinjection urodynamic analysis indicated that the urethral pressure profile significantly increased in the co-cultured group compared with other groups. The outcomes of this investigation indicated that the application of co-cultured adipose-derived and muscle-derived stem cells could be associated with higher therapeutic value in stress urinary incontinence patients compared with singular-cell treatments.

Development of Male External Urethral Sphincter and Tissue-Resident Stem/Progenitor Cells in Rats.

Stress urinary incontinence (SUI) after prostate surgery is primarily caused by urethral sphincter damage. There are few effective therapeutic approaches for male SUI due to both insufficient study of the structure of the external urethral sphincter (EUS) and incomplete understanding of the resident EUS stem/progenitor cells. The goals of this study were to localize and to determine the distribution of tissue-resident stem/progenitor cells in the male EUS throughout EUS development and to understand the anatomic temporal patterns of the EUS. Newborn Sprague Dawley rats were intraperitoneally injected with the thymidine analogue, 5-ethynyl-2-deoxyuridine (EdU), and the EUS was harvested at five time points (1, 2, 3, 4, and 8 weeks postinjection). The tissue was then processed for EdU staining and immunofluorescence staining for stem cell markers Ki67 and proliferating cell nuclear antigen. We counted the EdU+ label-retaining cells (LRCs) at each time point and colocalized with each stem cell marker, also we isolated and cultured the cells in vitro. The results revealed that the number of EdU+ LRCs in each EUS cross-section decreased over time and that the LRCs were located immediately under the basal membrane of laminin, densely adherent to the muscle fibers. In addition, the thickness of the striated muscle layer developed much faster than the smooth muscle layer during EUS development. By 4 weeks, the structure of the EUS layers was well differentiated. The EUS resident stem/progenitor cells were isolated with MACS® MicroBeads system, and myogenesis was confirmed. In this study, we defined both the time-course development of the EUS and the distribution of resident stem/progenitor cells. This information is crucial for forthcoming studies regarding male micturition and for development of novel therapeutic approaches for postoperative male SUI.

Cetacean Orbital Muscles: Anatomy and Function of the Circular Layers.

Dissections of cetacean orbits identified two distinct circular muscle layers that are uniquely more elaborate than the orbitalis muscles described in numerous mammals. The circular orbital muscles in cetaceans form layers that lie both external and internal to the rectus extra ocular muscles (EOMs). A cone-shaped external circular muscle (ECM) that invests the external surface of the rectus EOMs was found in all cetacean specimens examined. The cetacean ECM corresponds generally to descriptions of the musculus orbitalis in various mammals but is more strongly developed and has more layers than in noncetaceans. A newly identified internal circular muscle (ICM) is located internal to the rectus EOMs and external to the retractor bulbi (RB). The RB is massive in cetaceans and is encased in a connective tissue layer containing convoluted bundles of blood vessels. The most robust ECM and ICM layers were in sperm whale (Physeter macrocephalus) where they form complete rings. Surprisingly, histological analysis showed the sperm whale ECM to contain both smooth and striated (skeletal) muscle layers while the ICM appeared to contain solely skeletal muscle fibers. The extreme development of the ECM (orbitalis) and RB suggest a co-evolved system mediating high degrees of protrusion and retraction in cetaceans. We know of no homolog of the ICM but its function seems likely related to the complex vascular structures surrounding and deep to the retractor muscle. Skeletal muscle components in orbital circular muscles appear to be highly derived specializations unknown outside of cetaceans. Anat Rec, 2019. © 2019 American Association for Anatomy Anat Rec, 303:1792-1811, 2020. © 2019 American Association for Anatomy.

The effects of microenergy acoustic pulses on an animal model of obesity-associated stress urinary incontinence. Part 1: Functional and histologic studies.

Obesity is a strong independent risk factor for urinary incontinence. Effective therapeutic approaches for obesity-associated stress urinary incontinence (OA-SUI) are lacking as the mechanisms remain unclear. The aim of our study is to explore the impacts of microenergy acoustic pulse (MAP) therapy on urethral and pelvic floor muscle structure and function in female lean and fatty rats. A total 24 Zucker fatty (ZF) and 24 Zucker lean (ZL) female 24-week-old rats were grouped into four groups: ZL control, ZLMAP, ZF control, and ZFMAP. For MAP treatment, 500 pulses were delivered at an energy level of 0.033 mJ/mm 2 and a frequency of 3 Hz and were applied twice a week for 4 weeks. After a 1-week washout, all rats underwent conscious cystometry and leak-point pressure (LPP) measurements followed by ex vivo organ-bath assay and histological study. ZF rats had lower LPP as compared to ZL rats, and MAP treatment significantly improved LPP in ZF rats (P < .05). Impaired muscle contractile activity (MCA) in organ-bath study was noted in ZF rats. MAP treatment significantly increased MCA in ZF rats (P < .05) and also increased the thickness of the striated muscle layer and the number of neuromuscular junctions (NMJs). In situ, MAP activated muscle satellite cells significantly (P < .05). Obesity impairs the function of both the urethral sphincter and the pelvic floor and leads to atrophy and distortion of the striated muscle in obese female rats. These issues contribute to OA-SUI. MAP improves continence by stimulating muscle regeneration and nerve innervation as well as by activating satellite cells.

Morphology and microcirculatory structure of the urethra of the pig: Urologic surgical interest

The urethra of the sow can play an important role in the surgical revascularization or in the reconstructive surgery. However, the urethra can be easily injured if it possessed well architecture and vascularization. We investigated the morphological structure and vasculature features of the urethra to improve surgical results. Eight pelvises of sow were investigated. The block was cuts according to the segments of the urethra. They were made transparent according to the sagittal and transvers planes and examined trough Chinese ink agar injection. The adventia of both portions of the urethra of the sow (pelvic and perineal) were dependent on the collaterals of the internal iliac arteries and internal pudendal arteries. The veins of the periphery of the urethra derived from the muscle layers and the chorion and ran into a network in contact with arteries. The arteries of the striated muscle layer originated from the adventitial arteries of the anterior and lateral regions of the urethra. The chorion was depended on long vessels from the adventitious network and the terminal branches of the vessels of the inner longitudinal muscle layer. The arteries of the urethrovaginal septum were thin and came from the branches of the vaginal artery. The urethra of the sow was sheathed by the pelvic fascia lined with the elevated muscle of anus. They were well vascularized and can be safety exposed and preserved during experimental surgical dissection with careful drilling.Keys words: Sow urethra, morphology, structure, microvascularization.

Bilayer silk fibroin grafts support functional oesophageal repair in a rodent model of caustic injury.

Surgical repair of caustic oesophageal injuries with autologous gastrointestinal segments is often associated with dysmotility, dysphagia and donor site morbidity, and therefore alternative graft options are needed. Bilayer silk fibroin (BLSF) scaffolds were assessed for their ability to support functional restoration of damaged oesophageal tissues in a rat model of onlay oesophagoplasty. Transient exposure of isolated oesophageal segments with 40% NaOH led to corrosive oesophagitis and a 91% reduction in the luminal cross-sectional area of damaged sites. Oesophageal repair with BLSF matrices was performed in injured rats (n = 27) as well as a nondiseased cohort (n = 12) for up to 2 months after implantation. Both implant groups exhibited >80% survival rates, displayed similar degrees of weight gain, and were capable of solid food consumption following a 3-day liquid diet. End-point μ-computed tomography of repaired sites demonstrated a 4.5-fold increase in luminal cross-sectional area over baseline injury levels. Reconstructed oesophageal conduits from damaged and nondiseased animals produced comparable contractile responses to KCl and electric field stimulation while isoproterenol generated similar tissue relaxation responses. Histological and immunohistochemical evaluations of neotissues from both implant groups showed formation of a stratified, squamous epithelium with robust cytokeratin expression as well as skeletal and smooth muscle layers positive for contractile protein expression. In addition, synaptophysin positive neuronal junctions and vessels lined with CD31 positive endothelial cells were also observed at graft sites in each setting. These results provide preclinical validation for the use of BLSF scaffolds in reconstructive strategies for oesophageal repair following caustic injury.

Full-thickness oesophageal regeneration in pig using a polyurethane mucosal cell seeded graft

Malignant oesophageal pathology typically requires resection of a portion of oesophagus. The aim of this study was to investigate attachment and growth of swine oesophageal mucosal cells on electrospun synthetic nanofibre matrices of varying chemistries and to determine whether a mucosal-seeded graft, in a swine animal model, could induce regeneration. Swine mucosal oesophageal cells were isolated and seeded them onto five different matrix materials. Matrix samples were cultured for up to 14days, after which matrices were analysed for cell attachment. Attachment varied for each of the matrix materials tested, with the most rigid showing the lowest levels of attachment. Importantly, sections of these matrices illustrated that multiple layers of mucosal cells formed, mimicking endogenous oesophageal structure. A tdTomato reporter line (mucosaltdt cells) was created to enable cell tracking. As polyurethane matrix was found optimal through in vitro testing, a graft was prepared using mucosaltdt cells, along with an unseeded control, and implanted into swine for determination of oesophageal regeneration. Mucosal seeded polyurethane grafts initiated full thickness regeneration of the oesophagus, including epithelial, submucosal, and skeletal muscle layers which were highly vascularized. Interestingly, an unseeded graft showed similar regeneration, indicating that the role of cells in the process of oesophageal regeneration is still unclear. The electrospun polyurethane matrix does appear suitable for multilayered cellular attachment and growth of oesophageal mucosal cells, and implantation of polyurethane grafts initiated full thickness regeneration of the oesophagus, indicating potential for oesophageal reconstruction in humans. Copyright © 2016 John Wiley & Sons, Ltd.

Treatment of Oral Squamous Cell Carcinoma using Thymoquinone Loaded on Gold Nanoparticles

Background: Oral cancer is one of the most prevalent cancers. Thymoquinone has a potential therapeutic activity against cancer cells. Aim: to compare the effect ofthymoquinone and thymoquinone loaded on gold nanoparticles (GNPs-TQ) as systemic therapeutic agents through intraperitoneal injection for 3&6 weeks after painting of with DMBA 3 times/week for 14w. Material and Methods: This study was carried out on ninety male Syrian golden hamsters (n=90), its age ranged from 6 to 7 weeks, weighting 90-110 gm, purchased from Theodore Blhars Research Institute, Cairo, Egypt. Characterization of GNPs was achieved through using Ultraviolet-Visible spectroscope and transmission electron microscope (TEM). Tissue samples were examined through routine H&E stain, and nuclear factor kappa B cells (NF-κB) immunoreactivity. Results: Formation of spherical and well dispersed gold nanoparticles (GNPs) (27nm). Histopathological evaluation showed retardation of carcinogenesis in hamster buccal pouch and regeneration of striated muscle layers when treated with thymoquinone loaded on gold nanoparticles (GNPs-TQ). These observations were in line with decrease nuclear factor-kappa B expression. Conclusions: GNPs-TQ is a promising chemo-therapeutic agentin regression of carcinogenesis, and improving the general animal health.

Evaluation the Safety of Thymoquinone Loaded on Gold Nanoparticles in the Treatment of Hamster Buccal Carcinogenesis

Background: Oral canceris one ofthe most prevalent cancers. Thymoquinone (TQ) has a potential therapeutic activity against cancer cells. Aim: This study aimed to compare the effect of TQ and TQ loaded on gold nanoparticles (GNPs) as systemic therapeutic agents through intra-peritoneal injection for 3&6 weeks after painting with DMBA (3 times/week for 14w). Material and Methods: This study was carried out on ninety male Syrian golden hamsters (n=90), its age ranged from 6 to 7 weeks, weighting 90-110 gm, purchased from Theodore Blhars Research Institute, Cairo, Egypt. Characterization of GNPs was achieved through using Ultraviolet-Visible spectroscope and transmission electron microscope (TEM). Analysis for total white blood cells (WBCs) & lymphocytes count and lymphocytes % was done. To ensure the drugs safety, liver and kidney toxicity enzymes were measured. Results: Formation of spherical and well dispersed GNPs (27nm). There was marked increase in WBCs (13.8), lymphocyte count (8.2) and liver enzymes (99.6-104.4) after DMBA painting. These markers were reduced obviously after using of GNPs-TQ for 6w to 6.1, 5.4, 56.7, and 57.5 respectively. Histopathological evaluation showed regression of carcinogenesis and regeneration of striated muscle layers when treated with GNPs-TQ. Conclusions: GNPs-TQ is considered a promising chemo-therapeutic agent in treating carcinoma, without toxic effect on liver and kidney enzymes

Transgenic animal model for studying the mechanism of obesity-associated stress urinary incontinence.

To study and compare the function and structure of the urethral sphincter in female Zucker lean (ZL) and Zucker fatty (ZF) rats and to assess the viability of ZF fats as a model for female obesity-associated stress urinary incontinence (SUI). Two study arms were created: a ZL arm including 16-week-old female ZL rats (ZUC-Leprfa 186; n = 12) and a ZF arm including 16-week-old female ZF rats (ZUC-Leprfa 185; n = 12). I.p. insulin tolerance testing was carried out before functional study. Metabolic cages, conscious cystometry and leak point pressure (LPP) assessments were conducted. Urethral tissues were harvested for immunofluorescence staining to check intramyocellular lipid (IMCL) and sphincter muscle (smooth muscle and striated muscle) composition. The ZF rats had insulin resistance, a greater voiding frequency and lower LPP compared with ZL rats (P < 0.05), with more IMCL deposition localized in the urethral striated muscle fibres of the ZF rats (P < 0.05). The thickness of the striated muscle layer and the ratio of striated muscle to smooth muscle were lower in ZF than in ZL rats. Obesity impairs urethral sphincter function via IMCL deposition and leads to atrophy and distortion of urethral striated muscle. The ZF rats could be a consistent and reliable animal model in which to study obesity-associated SUI.

Current distribution in tissues with conducted electrical weapons operated in drive-stun mode.

The TASER® conducted electrical weapon (CEW) is best known for delivering electrical pulses that can temporarily incapacitate subjects by overriding normal motor control. The alternative drive-stun mode is less understood and the goal of this paper is to analyze the distribution of currents in tissues when the CEW is operated in this mode. Finite element modeling (FEM) was used to approximate current density in tissues with boundary electrical sources placed 40 mm apart. This separation was equivalent to the distance between drive-stun mode TASER X26™, X26P, X2 CEW electrodes located on the device itself and between those located on the expended CEW cartridge. The FEMs estimated the amount of current flowing through various body tissues located underneath the electrodes. The FEM simulated the attenuating effects of both a thin and of a normal layer of fat. The resulting current density distributions were used to compute the residual amount of current flowing through deeper layers of tissue. Numerical modeling estimated that the skin, fat and skeletal muscle layers passed at least 86% or 91% of total CEW current, assuming a thin or normal fat layer thickness, respectively. The current density and electric field strength only exceeded thresholds which have increased probability for ventricular fibrillation (VFTJ), or for cardiac capture (CCTE), in the skin and the subdermal fat layers. The fat layer provided significant attenuation of drive-stun CEW currents. Beyond the skeletal muscle layer, only fractional amounts of the total CEW current were estimated to flow. The regions presenting risk for VF induction or for cardiac capture were well away from the typical heart depth.

Decellularized dermal strip as a suburethral sling in a rat model of stress urinary incontinence.

To report the feasibility, efficacy and safety of decellularized dermal strip as a sling material in the pudendal denervated stress urinary incontinence (SUI) in an animal model. Thirty female Sprague-Dawley rats were randomly allocated into three equal groups (n = 10). In group 1, rats underwent bilateral pudendal nerve transection (BPNT) with no vaginal sling placement. Group 2 underwent BPNT with homologous decellularized dermal strip placement as vaginal sling 12 weeks later. Group 3 was considered as controls to evaluate baseline leak point pressure (LPP). Leak point pressure was measured 18 weeks after BPNT in group 1 and 6 weeks after sling implantation in group 2. Sling and sphincter samples were prepared for histological and immunohistochemistry (IHC) staining. H&E staining of external urethral sphincter showed decrease in striated muscle layer in group 1 (BPNT) compared to control confirmed by desmin staining (45 % decrease in desmin staining). Sling implantation caused significant increase in mean LPP from 11.6 ± 2.8 cm H2O in group 1 (BPNT) to 27.2 ± 5.4 cm H2O in group 2 (BPNT/sling). There was no significant difference between LPP after the sling placement in group 2 and LPP in group 3 (27.2 ± 5.4 cm H2O vs. 27.6 ± 5.9, P = 0.832). IHC staining was positive for α-SMA and CD34. Based on present results, this dermal strip could be considered as a potential sling material for treatment of SUI in this animal model. This study provides the basis for further investigation of the efficacy of biological decellularized scaffold as suburethral sling material.

The dose-effect safety profile of skeletal muscle precursor cell therapy in a dog model of intrinsic urinary sphincter deficiency.

Locally injected skeletal muscle precursor cells (skMPCs) integrate into and restore the muscle layers, innervation, vasculature, and function of the sphincter complex in animal models of intrinsic urinary sphincter deficiency (ISD). The goal of the present study was to test the dose-effect safety profile of skMPC therapy in a dog model of ISD. Sphincter deficiency was created in 20 adult female dogs by surgically removing the skeletal muscle layer of the urinary sphincter complex. skMPCs isolated from the hind leg were expanded in culture and injected 4 weeks later into the sphincter complex at a dose of 25 million cells (n = 5), 50 million cells (n = 5), or 100 million cells (n = 5) per milliliter in a 2-ml volume. Five dogs received no sphincter injection. The measures of maximal sphincter pressure, complete blood count, and blood chemistry were performed monthly until their sacrifice at 9 months. At that point, full necropsy was performed to assess the safety of the skMPC injections. Injection of different doses of cells had no effects on the body weight, blood cell count, or kidney or liver function test results (p > .05 among the skMPC doses). Some incidental pathologic features were found in the lower urinary tract in all groups and were most likely associated with repeat catheterization. The maximal urinary sphincter pressure was higher in the 50 million cells per milliliter treatment group than in the other experimental groups (p < .05). The findings of the present study have confirmed that urinary sphincter injection of skMPCs results in no significant local or systemic pathologic features within the dose range that improves sphincter pressures.

Advanced glycation end-product expression is upregulated in the gastrointestinal tract of type 2 diabetic rats.

To investigate changes in advanced glycation end products (AGEs) and their receptor (RAGE) expression in the gastrointestinal (GI) tract in type 2 diabetic rats. Eight inherited type 2 diabetic rats Goto-Kakizak (GK) and ten age-matched normal rats were used in the study. From 18 wk of age, the body weight and blood glucose were measured every week and 2 wk respectively. When the rats reached 32 wk, two-centimeter segments of esophagus, duodenum, jejunum, ileum, and colon were excised and the wet weight was measured. The segments were fixed in 10% formalin, embedded in paraffin and five micron sections were cut. The layer thickness was measured in Hematoxylin and Eosin-stained slides. AGE [N epsilon-(carboxymethyl) lysine and N epsilon-(carboxyethyl)lysine] and RAGE were detected by immunohistochemistry staining and image analysis was done using Sigmascan Pro 4.0 image analysis software. The blood glucose concentration (mmol/L) at 18 wk age was highest in the GK group (8.88 ± 1.87 vs 6.90 ± 0.43, P < 0.001), a difference that continued to exist until the end of the experiment. The wet weight per unit length (mg/cm) increased in esophagus, jejunum and colon from the normal to the GK group (60.64 ± 9.96 vs 68.56 ± 11.69, P < 0.05 for esophagus; 87.01 ± 9.35 vs 105.29 ± 15.45, P < 0.01 for jejunum; 91.37 ± 7.25 vs 97.28 ± 10.90, P < 0.05 for colon). Histologically, the layer thickness of the GI tract was higher for esophagus, jejunum and colon in the GK group [full thickness (μm): 575.37 ± 69.22 vs 753.20 ± 150.41, P < 0.01 for esophagus; 813.51 ± 44.44 vs 884.81 ± 45.31, P < 0.05 for jejunum; 467.12 ± 65.92 vs 572.26 ± 93.60, P < 0.05 for colon]. In esophagus, the AGE and RAGE mainly distributed in striated muscle cells and squamous epithelial cells. The AGE distribution was much stronger in the GK group compared to the normal group both in the striated muscle layer and mucosa layer (immuno-positive area/ total measuring area %: 4.52 ± 0.89 vs 10.96 ± 1.34, P < 0.01 for muscle; 8.90 ± 2.62 vs 22.45 ± 1.26, P < 0.01 for mucosa). No visible difference was found for RAGE distribution between the two groups. In the intestine AGE and RAGE distributed in epithelial cells of villi and crypt. RAGE was also found in neurons in the myenteric and submucosal plexus. The intensity of AGE staining in mucosa of all segments and RAGE staining in neurons in all segments were strongest in the diabetes group. Significant difference for AGE was found in the epithelial cells of villi and crypt in duodenum (immuno-positive area/total measuring area %: 13.37 ± 3.51 vs 37.48 ± 8.43, P < 0.05 for villi; 0.38 ± 0.12 vs 1.87 ± 0.53, P < 0.05 for crypt) and for RAGE in neurons of all segments (e.g., for jejunum: no staining neurons% 0 vs 0, mild 36.0 ± 5.2 vs 28.7 ± 3.5, moderate 53.2 ± 4.8 vs 55.8 ± 5.4, strong 10.7 ± 1.1 vs 15.4 ± 2.0, P < 0.05). In the colon, RAGE was primarily found in neurons in the myenteric and submucosal plexus. It was stronger in the diabetes group than in the normal group (no staining neurons% 6.2 ± 0.2 vs 0.3 ± 0.04, mild 14.9 ± 2.1 vs 17.6 ± 1.5, moderate 53.1 ± 4.6 vs 44.7 ± 4.4, strong 25.6 ± 18 vs 43.6 ± 4.0, P < 0.05). In the rectum, RAGE was primarily found in the mucosa epithelial cells. The AGE and RAGE expression was up-regulated in the GI tract of GK diabetic rats and may contribute to GI dysfunction in type 2 diabetic patients.

Embryonic Diffrentiation of the Colon of One Humped Camel (Camelus Dromedarius): A Histomorphology

A study involving histomorphological differentiation was conducted on the colon of 35 foetuses (both sex) of the one-humped camel collected from the Sokoto metropolitan abattoir, over a period of five months at different gestational ages. The approximate age of the fetuses was estimated and categorized into first, second and third trimester. Grossly, the color of the large intestine was whitish at first trimester and grayish to white in second and third trimester. The colon was divided into three main portions namely the ascending colon, the coiled and the descending part which formed the long part of the colon in second and third trimesters. At first trimester the coiled part was not differentiated but divided into two parts such as the centripetal and centrifugal part at second and third trimester. Histological observation of the tissues in this study revealed a complete structure of the tubular organ. The colon was found to consist of four layers namely: Tunica mucosa, Tunica sub mucosa, Tunica muscularis and Tunica serosa. The epithelium of the Tunica mucosa was stratified squamous epithelium with varying degree of stratification at first trimester and transformed to low columnar /cuboidal epithelium at second trimester. At third trimester, the epithelium was simple columnar epithelium. The lamina propria mucosa was found absent at first trimester but prominent at second and third trimester. The Lamina muscularis mucosa was found prominent at third trimester but not identified at first and second trimester. At first trimester of age tunica submucosa was prominent while at second trimester, it consisted of connective tissue cells and fibres scattered all over the layers with preliminary blood vessels. The cells and fibres were undifferentiated at this stage. There was no evidence of lymphatic nodular cells within the layer. At third trimester of age, the connective tissues and blood vessels were found prominent and the lymphatic nodular cells were found throughout the length of the colon. The tunica muscularis of camel colon consist of inner skeletal and outer longitudinal smooth muscle layers. At first trimester this layer did not differentiate into these two zones but only longitudinal orientation of smooth muscle layer. At second trimester, the layers of two zones with clear demarcation were observed. A thin layer of connective tissue comprising of undifferentiated cells lined the colon externally was observed in all the stages of development. Based on the above findings, it showed that development of the camels’ colon was histologically in succession and different from other domestic animals by having an extensive skeletal muscle at the tunica muscularis.

Myocardial signal intensity decay after gadolinium injection: a fast and effective method for the diagnosis of cardiac amyloidosis.

Late Gadolinium Enhancement (LGE) pattern of cardiac amyloidosis (CA) at cardiac magnetic resonance (CMR) examination is absent in approximately 30% of patients. We tested whether the evaluation of myocardial gadolinium signal intensity (SI) decay (SID) has a higher diagnostic accuracy for CA. CMR was performed in 59 patients with systemic AL amyloidosis (36 males, 69 ± 10 years, mean ± SD), and 20 age/sex-matched healthy controls. LGE images were acquired every minute up to 8 min after gadolinium injection (time of inversion 250 ms). SI regions of interest were plotted in SI/time curves for endocardial (Endo) and epicardial layer of interventricular septum, cavity, and skeletal muscle as reference. SID (a negative exponential function described by the parameter TSID) was expressed as number of heart beats (HB) from each ROI. The typical LGE pattern for CA was detected in 42 patients (Ty-LGE), while 17 showed either absent LGE or an atypical pattern (ATy-LGE). A definite CA diagnosis was confirmed in all Ty-LGE patients and in 10/17 ATy-LGE patients. At ROC analysis Endo-TSID was the most accurate parameter to distinguish Ty-LGE and ATy-LGE patients from controls. A 269 HB threshold (mean + 2 SD Endo-TSID measured in controls) identified 51/52 patients with definite CA diagnosis, with 98% sensitivity, 93% specificity, and 96% diagnostic accuracy. A direct relation was found between the extracellular volume and Endo-TSID in CA patients (r 0.72, 95% CI 0.37-089, p < 0.001). the analysis of myocardial SID after gadolinium injection improves the accuracy of CMR for CA diagnosis.