Laura Cavicchioli

Expression of calcium-binding proteins and selected neuropeptides in the human, chimpanzee, and crab-eating macaque claustrum

The claustrum is present in all mammalian species examined so far and its morphology, chemoarchitecture, physiology, phylogenesis and ontogenesis are still a matter of debate. Several morphologically distinct types of immunostained cells were described in different mammalian species. To date, a comparative study on the neurochemical organization of the human and non-human primates claustrum has not been fully described yet, partially due to technical reasons linked to the postmortem sampling interval. The present study analyze the localization and morphology of neurons expressing parvalbumin (PV), calretinin (CR), NPY, and somatostatin (SOM) in the claustrum of man (# 5), chimpanzee (# 1) and crab-eating monkey (# 3). Immunoreactivity for the used markers was observed in neuronal cell bodies and processes distributed throughout the anterior-posterior extent of human, chimpanzee and macaque claustrum. Both CR- and PV-immunoreactive (ir) neurons were mostly localized in the central and ventral region of the claustrum of the three species while SOM- and NPY-ir neurons seemed to be equally distributed throughout the ventral-dorsal extent. In the chimpanzee claustrum SOM-ir elements were not observed. No co-localization of PV with CR was found, thus suggesting the existence of two non-overlapping populations of PV and CR-ir interneurons. The expression of most proteins (CR, PV, NPY), was similar in all species. The only exception was the absence of SOM-ir elements in the claustrum of the chimpanzee, likely due to species specific variability. Our data suggest a possible common structural organization shared with the adjacent insular region, a further element that emphasizes a possible common ontogeny of the claustrum and the neocortex.

Fatal necrotizing fasciitis and myositis in a captive common bottlenose dolphin (Tursiops truncatus) associated with Streptococcus agalactiae

A common bottlenose dolphin (Tursiops truncatus) was presented for necropsy after acute onset of gastrointestinal signs and cutaneous lesions that rapidly progressed to death. Gross and microscopic findings were characterized by locally extensive severe necrohemorrhagic fasciitis and cellulitis, and severe necrotizing myositis in the head and dorsocranial thorax, with numerous disseminated gram-positive cocci. Streptococcus agalactiae was isolated from the lesions and from visceral organs (liver and lung), and it was identified by standard microbiology techniques. This communication is the first report of necrotizing fasciitis in a marine mammal associated with S. agalactiae.

Administration of Miltefosine and Meglumine Antimoniate in Healthy Dogs: Clinicopathological Evaluation of the Impact on the Kidneys

In canine leishmaniosis (CanL), kidneys are affected in virtually all dogs. Treatment of CanL is limited in Europe to meglumine antimoniate and miltefosine. This study evaluated the pharmacological, toxicological, and pathological effects of both drugs in healthy beagle dogs. Four male and four female dogs were divided into two groups. The animals in Group 1 were administered an oral solution of 2% of miltefosine at 2 mg/kg b.w. once a day, for twenty-eight days. The animals in Group 2 were administered a preparation of meglumine antimoniate at 100 mg/kg b.w. subcutaneously once a day for twenty-eight days. After treatment, all dogs were followed-up for a further twenty-eight days. Dogs were observed daily and clinically examined ten times throughout the study. On days -1 and 55 a renal biopsy was performed on all dogs and analyzed by light microscopy, immunofluorescence, and electron microscopy. All the examinations failed to demonstrate any lesions in the miltefosine-treated dogs. Conversely, all the meglumine antimoniate–treated dogs demonstrated severe tubular damage, characterized by tubular cell necrosis and apoptosis. In conclusion, although no clinical signs of renal disease were evident, the use of meglumine antimoniate in the pharmacological treatment approach of CanL-affected dogs should be carefully considered.

Cell Therapy for Parkinson's Disease: A Translational Approach to Assess the Role of Local and Systemic Immunosuppression

Neural transplantation is a promising therapeutic approach for neurodegenerative diseases; however, many patients receiving intracerebral fetal allografts exhibit signs of immunization to donor antigens that could compromise the graft. In this context, we intracerebrally transplanted mesencephalic pig xenografts into primates to identify a suitable strategy to enable long‐term cell survival, maturation, and differentiation. Parkinsonian primates received WT or CTLA4‐Ig transgenic porcine xenografts and different durations of peripheral immunosuppression to test whether systemic plus graft‐mediated local immunosuppression might avoid rejection. A striking recovery of spontaneous locomotion was observed in primates receiving systemic plus local immunosuppression for 6 mo. Recovery was associated with restoration of dopaminergic activity detected both by positron emission tomography imaging and histological examination. Local infiltration by T cells and CD80/86+ microglial cells expressing indoleamine 2,3‐dioxigenase were observed only in CTLA4‐Ig recipients. Results suggest that in this primate neurotransplantation model, peripheral immunosuppression is indispensable to achieve the long‐term survival of porcine neuronal xenografts that is required to study the beneficial immunomodulatory effect of local blockade of T cell costimulation.

Effects of long-term administration of recombinant human protein C in xenografted primates.

Background. The role potential of recombinant human activated protein C (rhaPC), a recently developed molecule with anticoagulant and antiinflammatory properties, in prolonging survival in immunosuppressed primate recipients of porcine renal xenografts has been evaluated. Methods. rhaPC was administered daily for 5 days (24 &mgr;g/kg/hr; group A; n=3) or throughout the postoperative period (8–24 &mgr;g/kg/hr; group B; n=2; or 24–48 &mgr;g/kg/hr; group C; n=4). Animals in group D (n=2) received rhaPC daily (24 &mgr;g/kg/hr) combined with recombinant human antithrombin (84 U/kg every 8 hr). Two animals served as control (group E). Results. The results indicate that rhaPC is protective against fibrin deposition early after transplantation but does not prevent fibrin deposition and the occurrence of acute humoral xenograft rejection (AHXR) later on. Animals in the study survived between 8 and 55 days. At the dose used, rhaPC is able to prevent fibrin deposition in the graft in the first 2 weeks after xenotransplantation, except when it is administered in conjunction with antithrombin. However, rhaPC did not prevent the eventual occurrence of AHXR in primate recipients of porcine xenografts. Conclusions. In this pig to primate model, rhaPC confers a short advantage in the prevention of early perioperative xenograft damage but does not represent an effective strategy for preventing AHXR.

Gastric B-Cell Lymphoma with Mott Cell Differentiation in a Dog

A gastric lymphoid tumor with involvement of regional lymph nodes and spleen was diagnosed in an 8-year-old crossbreed male dog with a 6-month history of gastrointestinal disease. Despite surgical excision and palliative therapy (prednisolone and cimetidine), the dog was euthanized due to worsening of clinical signs. At necropsy, multiple white, solid, nodular, infiltrative masses were observed in the stomach, duodenum, spleen, liver, and lungs in association with generalized lymph node enlargement. Cytology, histology, histochemistry, immunohistochemistry, and electron microscopy revealed that the neoplastic cell population was composed of B lymphocytes that contained variable amounts of round periodic acid-Schiff-positive cytoplasmic globules consistent with Russell bodies. The tumor most likely represented a variant of B-cell neoplasia with extensive Mott cell differentiation.

Inflammatory bowel disease mimicking alimentary lymphosarcoma in a cat.

L. Ragaini1*, G. Aste1, L. Cavicchioli2 and A. Boari1 1Department of Veterinary Clinical Sciences, Internal Medicine Section, School of Veterinary Medicine, University of T eramo, V.le Crispi 212, 64020, T eramo; 2Department of Public Health, Comparative Pathology and Veterinary Hygiene, School of Veterinary Medicine, University of Padua, Agripolis, V ia Romea 16, L egnaro, 35020, Padua, Italy *Correspondence: Dipartimento di Scienze Cliniche Veterinarie, Sezione di Medicina Interna, Facolta di Medicina Veterinaria, 64100 T eramo, Italy E-mail: ragaini@vet.unite.it

Experimental investigation of the biomechanics of urethral tissues and structures.

What is the central question of this study? Prostheses for treatment of urinary incontinence elicit complications associated with an inadequate mechanical action. This investigation aimed to define a procedure addressed to urethral mechanical characterization. Experimental tests are the basis for constitutive formulation, with a view to numerical modelling for investigation of the interaction between the tissues and a prosthesis. What is the main finding and its importance? Horse urethra, selected for its histomorphometric similarity to human urethra, was characterized by integrated histological analysis and mechanical tests on the biological tissue and structure, leading to constitutive formulation. A non‐linear, anisotropic and time‐dependent response was found, representing a valid basis for development of a numerical model to interpret the functional behaviour of the urethra.Urinary dysfunction can lead to incontinence, with relevant impact on the quality of life. This severe dysfunction can be surgically overcome by using an artificial urinary sphincter. However, several complications may result from an inappropriate prosthesis functionality, in many cases due to an unsuitable mechanical action of the device on urethral tissues. Computational models allow the investigation of mechanical interaction between biological tissues and biomedical devices, representing a potential support for surgical practice and prosthesis design. The development of such computational tools requires experimental data on biological tissues and structures mechanics, which are rarely reported in the literature. The present activities aim at providing a procedure for the mechanical characterization of urethral tissues and structures. The experimental protocol includes the morphometric and histologic analysis of urethral tissues, the mechanical characterization of tissues response by tensile and stress relaxation tests and the evaluation of urethral structural behavior by inflation tests. Results from preliminary experimental activities are processed adopting specific model formulations, also providing the definition of parameters that identify elastic and viscous tissues behavior. Different experimental protocols, leading to a comprehensive set of experimental data, allow for a reciprocal assessment of reliability of the investigation approach. This article is protected by copyright. All rights reserved

Systemic fatal type II coronavirus infection in a dog: Pathological findings and immunohistochemistry

Abstract A case of fatal systemic coronavirus infection is described in a 53-day-old Pekinese dog. Pathological findings and immunohistochemical identification using a monoclonal anti-canine Coronavirus antibody are included. Visceral lesions consisted of extensive fibrinopurulent bronchopneumonia, multiple renal cortical infarcts, severe coalescing centrilobular hepatic fatty change with minimal random hepatic necrosis, and multifocal splenic haemorrhage with lymphoid depletion. Moderate chronic diffuse enteritis was associated with intraluminal adult ascarids. Identification of type I and type II coronavirus in this subject had been previously confirmed by genotype-specific real-time reverse transcription-polymerase chain reaction (RT-PCR) assays of the intestinal contents, while only Coronavirus type II was detected in visceral organs. This case represents the first description of morphological lesions associated with a type II pantropic fatal coronavirus infection in the dog.

Circulating Cell-Free DNA in Dogs with Mammary Tumors: Short and Long Fragments and Integrity Index.

Circulating cell-free DNA (cfDNA) has been considered an interesting diagnostic/prognostic plasma biomarker in tumor-bearing subjects. In cancer patients, cfDNA can hypothetically derive from tumor necrosis/apoptosis, lysed circulating cells, and some yet unrevealed mechanisms of active release. This study aimed to preliminarily analyze cfDNA in dogs with canine mammary tumors (CMTs). Forty-four neoplastic, 17 non-neoplastic disease-bearing, and 15 healthy dogs were recruited. Necrosis and apoptosis were also assessed as potential source of cfDNA on 78 CMTs diagnosed from the 44 dogs. The cfDNA fragments and integrity index significantly differentiated neoplastic versus non-neoplastic dogs (P<0.05), and allowed the distinction between benign and malignant lesions (P<0.05). Even if without statistical significance, the amount of cfDNA was also affected by tumor necrosis and correlated with tumor size and apoptotic markers expression. A significant (P<0.01) increase of Bcl-2 in malignant tumors was observed, and in metastatic CMTs the evasion of apoptosis was also suggested. This study, therefore, provides evidence that cfDNA could be a diagnostic marker in dogs carrying mammary nodules suggesting that its potential application in early diagnostic procedures should be further investigated.