Extrinsic innervation of ileum and pelvic flexure of foals with ileocolonic aganglionosis.

Equine ileocolonic aganglionosis, which is also called lethal white foal syndrome (LWFS), is a severe congenital condition characterized by the unsuccessful colonization of neural crest progenitors in the caudal part of the small intestine and the entire large intestine. LWFS, which is attributable to a mutation in the endothelin receptor B gene, is the horse equivalent of Hirschsprung's disease in humans. Affected foals suffer from aganglionosis or hypoganglionosis of the enteric ganglia resulting in intestinal akinesia and colic. In other species with aganglionosis, fibers of extrinsic origin show an abnormal distribution pattern within the gut wall, but we have no information to date regarding this occurrence in horses. Our present aim is to investigate the distribution of extrinsic sympathetic and sensory neural fibers in LWFS, focusing on ileum and the pelvic flexure of the colon of two LWFS foals compared with a control subject. The sympathetic fibers were immunohistochemically identified with the markers tyrosine hydroxylase and dopamine beta-hydroxylase. The extrinsic sensory fibers were identified with the markers Substance P (SP) and calcitonin gene-related peptide (CGRP). Since SP and CGRP are also synthesized by subclasses of horse intramural neurons, LWFS represents a good model for the selective study of extrinsic fiber distribution. Affected foals showed large bundles of extrinsic fibers, compared with the control, as observed in Hirschsprung's disease. Furthermore, altered adrenergic pathways were observed, prominently in the pelvic flexure. The numbers of SP- and CGRP-immunoreactive fibers in the muscle, a target of enteric neurons, were dramatically reduced, whereas fibers deduced to be extrinsic sensory axons persisted around submucosal blood vessels. Fiber numbers in the mucosa were reduced. Thus, extrinsic innervation, contributing to modulate enteric functions, might also be affected during LWFS.

The trochanter tertius in a dog.

The tuberositas glutaea is a rudimentary structure in the dog's os femoris. It gives attachment to the superficial gluteal muscle, and is known by veterinary anatomists and orthopedic surgeons as trochanter tertius. We report an atypical eminence exposed through a surgical approach on a Cane Corso Dog. Anatomic and radiographic investigations led us to recognize this eminence as an abnormally grown tuberositas glutaea.

Mesenchymal stem cells and platelet gel improve bone deposition within CAD-CAM custom-made ceramic HA scaffolds for condyle substitution.

PURPOSE: This study evaluated the efficacy of a regenerative approach using mesenchymal stem cells (MSCs) and CAD-CAM customized pure and porous hydroxyapatite (HA) scaffolds to replace the temporomandibular joint (TMJ) condyle. METHODS: Pure HA scaffolds with a 70% total porosity volume were prototyped using CAD-CAM technology to replace the two temporomandibular condyles (left and right) of the same animal. MSCs were derived from the aspirated iliac crest bone marrow, and platelets were obtained from the venous blood of the sheep. Custom-made surgical guides were created by direct metal laser sintering and were used to export the virtual planning of the bone cut lines into the surgical environment. Sheep were sacrificed 4 months postoperatively. The HA scaffolds were explanted, histological specimens were prepared, and histomorphometric analysis was performed. RESULTS: Analysis of the porosity reduction for apposition of newly formed bone showed a statistically significant difference in bone formation between condyles loaded with MSC and condyles without (P < 0.05). The bone ingrowth (BI) relative values of split-mouth comparison (right versus left side) showed a significant difference between condyles with and without MSCs (P < 0.05). Analysis of the test and control sides in the same animal using a split-mouth study design was performed; the condyle with MSCs showed greater bone formation. CONCLUSION: The split-mouth design confirmed an increment of bone regeneration into the HA scaffold of up to 797% upon application of MSCs.

Effects of intraarticular treatment with stanozolol on synovial membrane and cartilage in an ovine model of osteoarthritis.

Aim of the study was to verify the clinical and morphological effects of intra-articular stanozolol or placebo treatment, lasting 3 and 9 months, in sheep in which a femoro-tibial osteo-arthritis (OA) were surgically induced (medial bilateral meniscectomy). Twenty healthy sheep divided into four groups and two control animals group, after surgical medial bilateral meniscectomy, were weekly injected in femoral-tibial joint (FTJ) with stanozolol or placebo. Lameness evaluation was performed and synovial fluid was collected from all sheep at each treatment time. Necropsies were performed after 3 or 9 month as described in experimental design. Gross pathologies were described and specimen tissues collected from femoro-tibial articular joints were processed for routine histological examination. The gross anatomy of the FTJ was well-preserved in stanozolol-treated sheep; this also applied to the histological features of articular cartilage. Joint aseptic inflammation and fibrosis were observed in placebo-treated sheep, associated with a different degree of severity of condylar and tibial plate cartilage degeneration. Stanozolol intra-articular treatment reduces osteophytes formation and subchondral bone reaction and promotes articular cartilage regeneration.

Endoscopic examination of the nasolacrimal duct in ten horses.

REASONS FOR PERFORMING STUDY: No endoscopic examination of the nasolacrimal duct has been described before. In contrast with other imaging techniques, endoscopy provides a direct inspection of the intralumen and ductal mucosa in standing sedation. OBJECTIVES: To provide a reference against which the endoscopic and clinical features of obstructive nasolacrimal disease in the horse may be compared. METHODS: Endoscopic examination of the nasolacrimal duct was performed in 10 French Thoroughbred bay mares with a 3 mm shaft diameter flexible fibrescope. The duct was divided into 3 zones (1, 2 and 3) from the nostril to the lacrimal sac. RESULTS: Endoscopic examination of the nasolacrimal duct appeared to be quite easy to perform in Zones 1 and 2, while the ease or difficulty of examining Zone 3 depended on the weight and size of the horse for the position of the endoscope in the lacrimal canal. CONCLUSIONS: Endoscopic inspection has provided the possibility of a novel diagnostic approach to conditions of the nasolacrimal duct in horses. POTENTIAL RELEVANCE: Endoscopic examination of the nasolacrimal duct could help to diagnose and treat nasolacrimal diseases by performing sample withdrawal and duct irrigation.

Cytological, immunohistochemical and mutational analysis of a gastric gastrointestinal stromal tumour in a cat.

Gastrointestinal stromal tumours (GISTs) represent a distinctive group of primary mesenchymal tumours of the gastrointestinal tract identified immunohistochemically by expression of CD117. A 10-year-old neutered female domestic shorthair cat with a history of recurrent vomiting was examined. The presence of a gastric mass was recognized and a laparotomy was performed. Cytological examination was consistent with a low-grade malignant mesenchymal tumour and histopathological investigation suggested myogenic differentiation of tumour cells. The diagnosis of GIST was confirmed by immunohistochemical expression of CD117. Sequence analysis of the KIT gene identified a deletion in exon 11. The same mutation is found often in human GISTs.

Sympathetic innervation of the ileocecal junction in horses.

The distribution and chemical phenotypes of sympathetic and dorsal root ganglion (DRG) neurons innervating the equine ileocecal junction (ICJ) were studied by combining retrograde tracing and immunohistochemistry. Immunoreactivity (IR) for tyrosine hydroxylase (TH), dopamine beta-hydroxylase (DBH), neuronal nitric oxide synthase (nNOS), calcitonin gene-related peptide (CGRP), substance P (SP), and neuropeptide Y (NPY) was investigated. Sympathetic neurons projecting to the ICJ were distributed within the celiac (CG), cranial mesenteric (CranMG), and caudal mesenteric (CaudMG) ganglia, as well as in the last ganglia of the thoracic sympathetic chain and in the splanchnic ganglia. In the CG and CranMG 91 +/- 8% and 93 +/- 12% of the neurons innervating the ICJ expressed TH- and DBH-IR, respectively. In the CaudMG 90 +/- 15% and 94 +/- 5% of ICJ innervating neurons were TH- and DBH-IR, respectively. Sympathetic (TH-IR) fibers innervated the myenteric and submucosal ganglia, ileal blood vessels, and the muscle layers. They were more concentrated at the ICJ level and were also seen encircling myenteric plexus (MP) and submucosal plexus (SMP) descending neurons that were retrogradely labeled from the ICJ. Among the few retrogradely labeled DRG neurons, nNOS-, CGRP-, and SP-IR nerve cells were observed. Dense networks of CGRP-, nNOS-, and SP-IR varicosities were seen around retrogradely labeled prevertebral ganglia neurons. The CGRP-IR fibers are probably the endings of neurons projecting from the intestine to the prevertebral ganglia. These findings indicate that this crucial region of the intestinal tract is strongly influenced by the sympathetic system and that sensory information of visceral origin influences the sympathetic control of the ICJ.

Comparison of endoscopy, histology, and cytokine mRNA of the equine gastric mucosa.

In recent years, gastric ulceration has been recognized as a common, possibly performance-limiting disease, of adult horses. The aim of this study was to compare endoscopic features, histological diagnosis, and mRNA levels of various cytokines (TNF-alpha, IL-1beta, and IL-13) from horse gastric biopsies. Eleven horses suffering from equine gastric ulcer syndrome and seven horses with normal histological gastric features were assessed. No correlation between endoscopic features and histology (i.e., the gold standard) was observed. Based on histological diagnosis, a significant (p < 0.05) increase in cytokine mRNA levels (specifically, TNF-alpha and IL-13) was observed in horses affected by equine ulcerative gastric syndrome.

Thymofibrolipoma in two dogs.

Thymolipomas are unusual benign neoplasms composed of mature adipose and thymic tissue that represent less than 10% of all thymic tumours in man. A thymofibrolipoma is a histological variant of thymolipoma in which there is an additional abundance of fibrous connective tissue. Thymolipoma has been reported previously in one dog and one cat, but thymofibrolipoma has never been described. This report documents the clinical and pathological features of two cases of canine thymofibrolipoma.

Rupture of the lateral lobe of the biceps brachii tendon in an Arabian horse.

Rupture of the lateral lobe of the proximal tendon of the biceps brachii muscle was diagnosed in an Arabian horse. To the authors' knowledge, this is the only report of this condition in horses. Although clinical signs were helpful in the identification of the location of disease, ultrasonographic examination was a more definitive and non- invasive means of diagnosing the pathological condition. Bursoscopic examination of the intertubercular bursa was also useful in obtaining confirmation of the diagnosis, and for debridement and lavage of the bursa.

Intrinsic innervation of the ileocaecal junction in the horse: preliminary study.

REASON FOR PERFORMING STUDY: In horses, morpho-functional studies related to the enteric nervous system (ENS) controlling the sphincters are lacking. OBJECTIVES: To investigate immunohistochemically the morphology, distribution, density, phenotypes and projections of neurons controlling the ileocaecal junction (ICJ). METHODS: Two young horses were anaesthetised and underwent midline laparotomy. The neuronal retrograde fluorescent tracer Fast Blue (FB) was injected into the wall of the ICJ. A post surgical survival time of 30 days was used. Following euthanasia, the ileum and a small portion of caecum were removed. Cryosections were used to investigate the immunoreactivity (IR) of the neurons innervating the ICJ for choline acetyltransferase (ChAT), neuronal nitric oxide synthase (nNOS), substance P (SP), calcitonin gene-related peptide (CGRP) and neurofilament NF200kDa (NF). RESULTS: Ileal FB-labelled neurons innervating the ICJ were located in the myenteric plexus (MP) and submucosal plexus (SMP) up to 48 cm and 28 cm, respectively, from the point of the FB injections. Descending MP and SMP neurons were nitrergic (54 +/- 11% and 68 +/- 4%, respectively), cholinergic (60 +/- 19% and 82 +/- 11%, respectively), NF-IR (54 +/- 9% and 78 +/- 21%, respectively), and SP-IR (about 20% in both the plexuses). CGRP-IR was expressed only by SMP descending neurons (45 +/- 21%). In both the plexuses descending neurons coexpressing nNOS- and ChAT-IR were also observed (25 +/- 11% and 61 +/- 27%, respectively). CONCLUSIONS: The presence of ileal long projecting neurons innervating the ICJ suggests that they are critical for its modulation. Consequently, in bowel diseases in which the resection of the terminal jejunum and proximal ileum are required, it is preferable, whenever possible, to conserve the major portion of the ileum. POTENTIAL RELEVANCE: The knowledge of the phenotype of ENS neurons of the ileum might be helpful for developing pharmaceutical treatment of the ICJ motility disorders.

Biomechanics in young and adult italian standardbred trotter horses in real racing conditions.

This study was undertaken to characterize and establish the kinematic standards of Italian standardbred trotter horses in real racing conditions. Certain parameters, such as the angles of both front and hind fetlock joints, stride length, stride frequency and average speed in youngs and adults are presented, examinated and compared with statistical tests. The angles and stride length were obtained using ONTRACK software over frames extracted from two CANON MV630i digital videocameras. For the stride frequency, a third identical videocamera filmed the horses to count the number of beats per minute. The average speed was calculated by multiplying the stride frequency by the stride length and transforming the result into kilometers per hour. The data reveal that as speed increases, younger horses have more extended fetlock joints than adults. Contrary to this, at the maximum speed (hereafter referred to as sprint speed) the adults increase both their stride frequency and stride length, while young horses increase stride frequency and decrease stride length. We think that the knowledge of these parameters in competition breeds could have potential relevance as they may reveal early indicators of the development of proper and adequate characteristics in young horses of those breeds.

Mechanoreceptors in the medial and lateral glenohumeral ligaments of the canine shoulder joint.

In order to have a better understanding of the role of ligaments in canine shoulder joint stability, the presence of mechanoreceptors in the medial (MGHL) and lateral (LGHL) glenohumeral ligaments was detected by means of a modified gold chloride stain. Three morphologically distinct mechanoreceptors were identified: Ruffini receptors (type I endings), Pacinian corpuscles (type II endings) and Golgi tendon organ-like receptors (type III endings). These receptors are mainly localized at each end of the ligaments and are prevalently in their glenoid portion. In particular, in the MGHL the highest density was at the cranial arm of the insertion into the scapula. The variety of mechanoreceptors in canine shoulder ligaments might indicate an afferent function in providing the CNS with joint proprioceptive information. Therefore, besides acting as passive mechanical stabilizers, the MGHL and the LGHL may serve as sensory structures, contributing actively to joint stability. Ligamentous injuries which occur in shoulders not only affect mechanical restraint but also alter the proprioceptive input to the CNS by means of disruption of the mechanoreceptors.

Phase I clinical trial with the AMC-bioartificial liver.

UNLABELLED: Recently a bio-artificial liver (BAL) system has been developed at the Academic Medical Center (AMC) of Amsterdam to bridge patients with acute liver failure (ALF) to orthotopic liver transplantation (OLT). After successful testing of the AMC-BAL in rodents and pigs with ALF, a phase I study in ALF patients waiting for (OLT) was started in Italy. We present the safety outcome of the first 7 patients aged 21-56 years with coma grade III or IV The total AMC-BAL treatment time ranged from 8 to 35 hours. Three patients received 2 treatments with two different BAL's within three days. Six of the 7 patients were successfully bridged to OLT. One patient showed improved liver function after two treatments and did not need OLT. No severe adverse events of the BAL treatment were noted. CONCLUSION: Treatment of ALF patients with the AMC-BAL is a safe and feasible technique to bridge the waiting time for an adequate liver-graft.