Rodolfo Gialletti

Long-term safety and tolerance of silicone and self-expandable airway stents: an experimental study

BACKGROUND A variety of respiratory stents are currently available, but the ideal airway prosthesis seems far from being recognized. The objective of this study was to verify safety and long-term effect on the bronchial wall of three different types of airway stents. METHODS Twelve healthy adult sheep were divided in three groups, scheduled to receive: (1) bare self-expandable metallic stents (Gianturco); (2) silicone stents (Dumon); and (3) covered self-expandable synthetic stents (Polyflex). Insertions were performed through a rigid bronchoscope under general anesthesia. Chest roentgenogram was performed 1 and 6 months after surgery, and flexible bronchoscopy after 6 months. Twelve months postoperatively, the animals were killed and a postmortem examination was carried out. RESULTS All Polyflex stents migrated during the observation period; one late migration was observed in the Dumon group. Microscopic study showed: (1) Gianturco stents: full-thickness perforation of the bronchial wall covered by a thick layer of a chronic inflammatory infiltrate. Infection by Candida at the bottom of some ulcerations; (2) Dumon stents: mild bronchial inflammation (squamous metaplasia, submucosal inflammatory infiltrates; granuloma-like infiltrates). In case of displacement, no significant changes of the previously stented bronchus occurred; and (3) Polyflex stents: no changes of the previously stented bronchi. CONCLUSIONS Gianturco stents proved unsafe in the long term, owing to the risk of severe airway wall damage. The Polyflex stent is well tolerated but presents a high migration rate. Silicone stents show several limitations but appear to be well tolerated by the host mucosa.

Is there a statistical correlation between ultrasonographic findings and definitive diagnosis in horses with acute abdominal pain

REASON FOR PERFORMING STUDY Abdominal ultrasonography has become a part of the diagnostic investigation for the acute abdomen in many equine clinics. There is limited information on the correlation between abnormalities detected on abdominal ultrasonography and the specific category of small intestine (SI) and large intestine (LI) diseases. OBJECTIVES To investigate the relationship between abdominal ultrasonographic findings and disease categories that cause abdominal pain requiring surgery. METHODS Medical records were reviewed for horses undergoing surgery or post mortem examination for colic. The ultrasound examination was performed to assess free peritoneal fluid, the left kidney, stomach, appearance and motility of the duodenum, identification, appearance, motility and thickness of small intestine loops, and the appearance and motility of the colon. Logistic regression analysis was used to identify associations between disease categories and ultrasonographic findings; a Chi-squared test was used to test for associations between each variable and disease categories. RESULTS The study included 158 horses. Distended and nonmotile SI loops were associated with strangulated obstruction (n = 45); increased free peritoneal fluid, completely distended SI loops with abnormal motility and thickened loops were associated with definitive diagnosis involving SI (n = 58). Failure to visualise the left kidney was associated with renosplenic entrapment (n = 16); thickened large colon (LC) was associated with LC strangulating volvulus (n = 9). CONCLUSION The use of abdominal ultrasonography can be used for the accurate definitive diagnosis involving SI and LI diseases. POTENTIAL RELEVANCE This retrospective study may be used as a basis for prospective studies to assess the ultrasonographic findings in horses with medical colic and to compare these with surgical findings.

Transplantation of allogeneic/xenogeneic pancreatic islets containing coherent microcapsules in adult pigs.

WE HAVE PREVIOUSLY described a method for fabrication of alginate/polyaminoacidic CM. Thereafter, we completed assessment of either morphological properties of structural as well as ultrastructural level, or in vitro immunoselectivity, or in vivo post-transplant (Tx) functional performance in diabetic rodents of these new biomembranes for islet Tx immunoprotection in full absence of the recipient’s pharmacological immunosuppression. Because CM, unlike conventional-size microcapsules (CSM), measuring an average 600 to 800 mm in equatorial diameter, hold the unique advantage of occupying a volume which is almost coincident with that of naked islets, these new microimmunobarriers could address a number of unsolved problems with regard to encapsulated islet cell Tx in diabetic large mammalians. One of the most formidable hurdles to this approach for the therapy of insulin-dependent diabetes mellitus has consisted of inadequacy of implant sites for encapsulated islets. Because of the final excessive CSM’s Tx size, these capsules had been only implanted in the peritoneal cavity. Unfortunately, even if highly biocompatible, intraperitoneally grafted, islet-containing microcapsules had often provoked severe, possibly mass-related (60 to 80 mL/diabetic dog) inflammatory cell reaction. Dense connective tissue infiltration invariably resulted in impairment of biochemical exchange, ultimately leading to Tx failure. After testing the new CM in either in vitro functional and immunological or in vivo rodent diabetes-correction studies, we had embarked on assessment of CM biocompatibility, after multiple-site transplantation into adult pigs. Preliminarily, we have shown that empty CM, per se, indeed were biocompatible in this large-size mammal animal model, with a very low degree of sensitization being induced by repeated CM-Tx booster. In an attempt to determine whether CM, because of their minimal size, would permit access to Tx sites so far interdicted to CSM, including parenchymatous organs, with full retention of the encapsulated allogeneic/xenogeneic islet cell viability, we have transplanted porcine or canine islet containing CM into multiple Tx sites, and examined them histologically, at 30 days post-Tx, in normal, adult pigs. MATERIALS AND METHODS Animals

Ultrasonographic findings in 38 horses with septic arthritis/tenosynovitis.

Septic arthritis/tenosynovitis in the horse can have life-threatening consequences. The purpose of this cross-sectional retrospective study was to describe ultrasound characteristics of septic arthritis/tenosynovitis in a group of horses. Diagnosis of septic arthritis/tenosynovitis was based on historical and clinical findings as well as the results of the synovial fluid analysis and/or positive synovial culture. Ultrasonographic findings recorded were degree of joint/sheath effusion, degree of synovial membrane thickening, echogenicity of the synovial fluid, and presence of hyperechogenic spots and fibrinous loculations. Ultrasonographic findings were tested for dependence on the cause of sepsis, time between admission and beginning of clinical signs, and the white blood cell counts in the synovial fluid. Thirty-eight horses with confirmed septic arthritis/tenosynovitis of 43 joints/sheaths were included. Degree of effusion was marked in 81.4% of cases, mild in 16.3%, and absent in 2.3%. Synovial thickening was mild in 30.9% of cases and moderate/severe in 69.1%. Synovial fluid was anechogenic in 45.2% of cases and echogenic in 54.8%. Hyperechogenic spots were identified in 32.5% of structures and fibrinous loculations in 64.3%. Relationships between the degree of synovial effusion, degree of the synovial thickening, presence of fibrinous loculations, and the time between admission and beginning of clinical signs were identified, as well as between the presence of fibrinous loculations and the cause of sepsis (P ≤ 0.05). Findings indicated that ultrasonographic findings of septic arthritis/tenosynovitis may vary in horses, and may be influenced by time between admission and beginning of clinical signs.

The Use of Alpha-2 Agonists in the Equine Practice: Comparison between Three Molecules

Nannarone, S., Gialletti, R., Veschini, I., Bufalari, A. and Moriconi, F., 2007. The use of alpha-2 agonists in the equine practice: comparison between three molecules. Veterinary Research Communications, 31(Suppl. 1), 309–312

Arthroscopic anatomy of the equine cervical articular process joints

REASON FOR PERFORMING STUDY Although arthropathy of the cervical articular process joints (APJs) is common, descriptions of the arthroscopic technique of the cervical APJ have not been reported previously. OBJECTIVES To develop an arthroscopic approach to the APJ and to describe the arthroscopic anatomy of the APJ. STUDY DESIGN Descriptive cadaver study and clinical case report. METHODS The regional anatomy was reviewed and the technique developed on fresh cadaver necks. A series of cadaveric APJ arthroscopies from C2-C3 to C6-C7 were performed to evaluate the procedure, which was then used in 3 clinical cases. A description of the procedure and the potential complications encountered were recorded. RESULTS The equine APJ consists of cranioventral and caudodorsal recesses; a single entry point at one of these recesses enables almost complete evaluation of cartilage surfaces and the synovial membrane and its villi. Successful entry into both APJ recesses was achieved in 22 cadaveric APJs and 5 APJs in the 3 clinical cases operated upon. An instrument portal was created to assess the feasibility of surgical arthroscopy. Complications were minor, and dissection of the APJs following the arthroscopic exploration revealed that the cartilage and periarticular neurovascular structures were not damaged during the procedure. CONCLUSIONS This study shows that arthroscopic examination of the APJs of equine cervical vertebra is feasible and can be performed in mature horses. Arthroscopy of the APJs may provide additional diagnostic information compared to conventional diagnostic techniques.

Histological and immunohistochemical studies of changes in myenteric plexuses and in interstitial cells of Cajal associated with equine colic.

In this study we investigated the histological changes of the myenteric plexuses and interstitial cells of Cajal (ICC) in gut samples from horses with colic to try to find results useful in the prognostic evaluation of enteric lesions. A morphologic and quantitative study of myenteric ganglia, ganglion cells and neuronal chromatolytic and necrotic changes of 24 horses with colic was performed. For ganglion cells, enteroglial cells and ICC immunolabeling was also performed to identify cell functional disorders. A significant increase of neuronal chromatolysis and necrosis occurred in horses suffering from colic throughout the gut. The neuron-specific enolase (NSE) and synaptophysin immunoreaction quantified with image analysis showed a significant loss of neuronal activity in all intestinal tracts of the animals under study associated with a significant loss of ICC immunoreactivity. The results supports immunohistochemical evaluation of ENS and ICC as a useful tool along with morphometric investigations in the evaluation of gut lesions produced during colic syndrome.

Extensive Myenteric Ganglionitis in a Case of Equine Chronic Intestinal Pseudo-obstruction Associated with EHV-1 Infection

A 7-year-old male trotter horse with a history of recurrent colic displayed clinical findings consistent with chronic intestinal pseudo-obstruction (CIP). At laparotomy, an impaction of the descending colon associated with marked atrophy of the right dorsal colon was found. The horse was humanely destroyed and tissues collected at necropsy examination revealed diffuse enteric ganglionitis comprising an infiltrate of CD3(+) T lymphocytes and plasma cells. At all levels of the intestinal tract the number of myenteric ganglia and of normal ganglion cells was decreased significantly. There were chromatolytic or necrotic neurons and the amount of connective tissue surrounding ganglia was increased. Immunohistochemical studies demonstrated slightly reduced expression of neuron-specific enolase and a moderate increase in expression of S100 and glial fibrillary acidic protein in a sample of right dorsal colon taken during the necropsy examination compared with a biopsy sample taken from the same location. Immunolabelling and semi-nested polymerase chain reaction for equine herpesvirus (EHV)-1 performed on the gut were positive, supporting an aetiological relationship between EHV-1 infection and the enteric ganglionitis.

Evaluation of transabdominal ultrasound as a tool for predicting the success of abdominocentesis in horses

The aim of this study was to evaluate the transabdominal ultrasonography as a tool for predicting the success of abdominocentesis in horses. Patients were included in the study if a complete transabdominal ultrasonography examination and abdominocentesis were performed as part of the clinical work-up. Ultrasonographically, the amount of peritoneal fluid was assessed using a 4-point grading system, as well as the amount of peritoneal fluid collected. A χ2 or Fischer exact test was performed to test for an association between the ultrasonography findings and fluid retrieved, and between the two grading scales. Interobserver and intraobserver agreement values were calculated using k statistics. Values of P<0.05 were considered significant; 109 horses met the inclusion criteria. Peritoneal fluid was identified ultrasonographically in 72 per cent of horses, and it was collected from 93 per cent of these cases. In horses with no peritoneal fluid identified at ultrasonography (28 per cent), fluid was collected in 70 per cent of cases. There is a significant association between transabdominal ultrasonography detection of peritoneal fluid and the likelihood to obtain a diagnostic amount of peritoneal fluid at abdominocentesis; however, even when peritoneal fluid is not detected during abdominal ultrasonography examination, an amount of peritoneal fluid useful for gross, clinicopathological and cytological evaluation can frequently be obtained.

Umbilical infections in foals: microbiological investigation and management

This study aims to investigate the bacteria involved in equine omphalitis and their susceptibility to antimicrobial drugs, and consequently to provide guidelines concerning the most suitable treatment protocol in accordance with the clinical, ultrasound and laboratory findings. Forty foals aged between one and 30 days were evaluated in the course of this investigation. An ultrasound examination of all umbilical remnants was carried out carefully in all foals; umbilical swabs were collected for bacteriological examination, and blood samples were collected for blood culture from 19 foals with fever and abnormal blood values. Bacterial omphalitis was observed in 95 per cent of foals and bacterial septicaemia was diagnosed in 11 cases. Enterobacteria and coccoid Gram-positive bacteria were isolated more frequently than Serratia marcescens, Pantoea agglomerans and Trueperella pyogenes. Omphalectomy was performed in 77.5 per cent of the foals examined; the remainder were treated only medically with antimicrobial drugs as recommended by antibiotic susceptibility testing performed for all bacteria isolated. Antibiotic therapy was successful in all foals that only received medical treatment; nevertheless, omphalectomy was performed in most cases particularly in situations of clinical decline despite antibiotic therapy and when involvement of umbilical vein, fever and joint disorders were observed.