Evaluation of calciotropic hormones in cats with odontoclastic resorptive lesions

OBJECTIVE: To assess associations between epidemiologic and laboratory variables and calciotropic hormones in cats with odontoclastic resorptive lesions (ORLs). ANIMALS: 182 client-owned cats older than 1 year of age with oral disease. PROCEDURE: Information on medical history, behavior, living environment, and feeding management was assessed by use of a questionnaire. After induction of general anesthesia, oral examination was performed following standardized protocols and included dental probing and full-mouth radiography. Laboratory analyses included evaluation of FeLV-FIV status, serum biochemical analyses, CBC, urinalysis, and serum concentrations of intact parathyroid hormone (iPTH), parathyroid hormone-related peptide (PTHrP), 25-hydroxyvitamin D (25-OHD), free thyroxine (fT4), and ionized calcium (iCa). RESULTS: ORLs were identified in 72.5% of cats. Mandibular third premolars were the most commonly affected teeth. Cats with ORLs were significantly older (mean, 9.2 years) than cats without ORLs (mean, 6.6 years). Multivariate logistic regression analysis revealed that 25-OHD, urine specific gravity, jaw-opening reflex on probing, and missing teeth were significant variables, even after accounting for age. Cats with ORLs had significantly higher mean serum concentration of 25-OHD (112.4 nmol/L) and significantly lower mean urine specific gravity (1.0263), compared with cats without ORLs (89.8 nmol/L and 1.0366, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: Results did not indicate associations between iPTH, PTHrP, or fT4 and development of ORLs. In affected cats, the importance of high serum 25-OHD and low urine specific gravity has not been determined.     

Different patterns in the histology and autofluorescence of the Harderian glands of the Syrian Hamster, rat, mouse, Mongolian gerbil and guinea pig

The purpose of this study was to compare the natural fluorescence in the Harderian glands of the Syrian hamster, rat, mouse, Mongolian gerbil and guinea pig (both sexes). For each species, 10 animals (five males and five females) were used. Histological autofluorescence studies were performed using a fluorescence microscope (450-490 nm filter). Two different types of fluorescent cells were observed in both hamster (type AFI high intensity and type AFII, low fluorescence) and rat (type AFI, low fluorescence and type AFII, high fluorescence) Harderian glands. The fluorescence was basally located in all mice cells, whereas it was observed near the epithelial cell nuclei in the Mongolian gerbil (occupying two-thirds and one-third of the cells in males and females, respectively). A high intensity of fluorescence was present throughout the acinar cells in the guinea pig. The patterns of fluorescence identified exhibited a sexual dimorphism in all species studied. These results demonstrate that the Harderian glands of the animal species examined exhibit a variety of histological autofluorescence patterns.     

Inhibition of the bactericidal activity of bovine polymorphonuclear leucocytes and related systems by casein.

Polymorphonuclear leucocytes (PMN) obtained from lactating cows' udders were deficient in their ability to kill Staphylococcus aureus compared with PMN isolated from blood. However, blood PMN suspended in separated milk or in the presence of casein were similarly impaired. Casein was found to inhibit in vitro the bactericidal activities of histone, the lactoperoxidase-H2O2-KI system and PMN lysates. Electron microscopy showed that casein was ingested by PMN with the formation of phagocytic vacuoles. These observations provide the basis of a hypothesis explaining the bactericidal deficiency of milk PMN and the consequent susceptibility of the udder to infection.     

Oral examination results in rescued ferrets: clinical findings

Ferrets have increased in popularity as pets, and a growing number are seen in companion animal practice. Domestic ferrets are commonly used as animal models for research of human oral conditions. The present study evaluated the prevalence of oral pathology in rescued ferrets which - to the authors' knowledge - has not yet been described in the scientific literature. Conscious oral examination was performed on 63 ferrets, of which 49 underwent general anesthesia for further examination. The most common clinical findings included malocclusion of mandibular second incisor teeth (95.2%); extrusion of canine teeth (93.7%); and abrasion and attrition of teeth (76.2%). Tooth fractures were exclusively associated with canine teeth and found in 31.7% of ferrets. Pulp exposure was confirmed in 60.0% of fractured teeth. The normal gingival sulcus depth measured < 0.5-mm in 87.8% of anesthetized ferrets. Clinical evidence of periodontal disease was present in 65.3% of anesthetized ferrets (gingivitis or probing depths > 0.5-mm), however advanced periodontal disease (i.e. periodontal pockets > 2-mm or stage 3 furcation exposure) was not found upon clinical examination. There was no evidence of tooth resorption, dental caries, stomatitis, or oral tumors in the examined group of ferrets.     

Feline odontoclastic resorptive lesions an unsolved enigma in veterinary dentistry.

This article presents a comprehensive review of the literature on feline odontoclastic resorptive lesions (FORLs), including etiopathogenesis, prevalence and predisposition, classification, histopathologic appearance, diagnosis, and treatment. Approximately one-third of all domestic cats may develop FORLs during their life span, and the risk of developing FORLs increases with age. Sophisticated dental treatments promise neither cure nor permanent improvement of affected teeth. Extraction is the current treatment of choice. Research on the etiology of FORLs has not been rewarding in recent years, and the causative factors contributing to the development of FORLs are still unknown.     

Computed tomographic appearance of masticatory myositis in dogs: 7 cases (1999-2006)

OBJECTIVE: To document computed tomography (CT) features in dogs with masticatory myositis. DESIGN: Retrospective case series. ANIMALS: 7 dogs with an immunologic diagnosis of masticatory myositis and an absence of clinical abnormalities of any skeletal muscles other than the masticatory muscles. PROCEDURES: History; clinical, hematologic, biochemical, immunologic, cytologic, and histologic findings; and pre- and postcontrast CT imaging features of masticatory muscles and head and neck lymph nodes were extracted from medical records. RESULTS: On CT images, changes in size (atrophy or swelling) were common for all masticatory muscles except the digastricus muscles, which were involved only in 1 dog. Pre-contrast attenuation changes, most often hypoattenuation with varied distribution patterns, were seen in masticatory muscles of 4 dogs. Contrast enhancement with a predominantly inhomogeneous distribution pattern was seen in the temporalis, masseter, and pterygoid muscles of all dogs. Head and neck lymph nodes were enlarged in all but 1 dog and had contrast enhancement with predominantly central or homogeneous distribution patterns. Muscle biopsy was performed in 6 dogs, with biopsy specimens obtained from areas that had the most obvious contrast enhancement on CT images. For all 6 dogs, biopsy specimens had histologic features indicative of masticatory myositis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that CT may be a useful adjunct in the diagnosis of masticatory myositis in dogs, including selection of sites for diagnostic muscle biopsy.     

Characterization and quantification of ceramides in the nonlesional skin of canine patients with atopic dermatitis compared with controls

As in humans, there is mounting evidence in support of an abnormal skin barrier contributing to the pathogenesis of canine atopic dermatitis (AD). Studies in people with AD have associated an abnormal skin barrier with deficiencies in ceramides, which represent important components of the stratum corneum (SC) intercellular lipid lamellae. Therefore, the goal of this study was to determine if the SC of dogs with AD is deficient in ceramides compared to normal dogs. Samples of SC were obtained from nonlesional skin of the caudal abdomen of 14 patients with AD and 14 age-, breed- and sex-matched healthy controls using a cyanoacrylate stripping procedure, and the subclass and relative amount of ceramides were assessed blindly by thin layer chromatography. Paired t -tests using R statistical computer software revealed the percentage amounts of ceramides 1 and 9 were significantly lower in nonlesional skin of AD dogs compared to controls ( P = 0.034 and P = 0.047, respectively), and the cholesterol percentage amount was significantly higher in AD dogs than in controls ( P = 0.016). Furthermore, the cholesterol/ceramide ratio was significantly higher in the AD group with respect to controls ( P = 0.014). These findings suggest that decreased amounts of ceramides in the skin of dogs with AD may be involved in the impaired barrier function of their skin.     

Investigation of the pruritogenic effects of histamine, serotonin, tryptase, substance P and interleukin-2 in healthy dogs

There are numerous studies of the pruritus-producing effects of histamine, serotonin, tryptase, substance P and interleukin-2 in humans and mice, but very little reported in dogs even though a common reason dogs are presented to veterinarians is pruritus. The aim of this study was to determine whether substances known to cause pruritus in humans also cause pruritus in dogs. Twenty-five clinically healthy research beagle dogs were included in the study. All dogs first received an intradermal injection of 0.05 mL saline as a control substance and were video-recorded for 20 min before and after the injection. Twenty-four hours later the dogs were randomly divided into five groups of five dogs each and randomly assigned to receive histamine, serotonin, tryptase, substance P or interleukin-2 injected intradermally each at the volume of 0.05 mL. On subsequent days, increasing concentrations of each substance were used. Before (baseline) and after the injection of each concentration of the substances, the dogs were video-recorded for 20 min. The frequency and character of pruritus episodes (scratching, licking, chewing, rubbing or rolling) were noted and these data were used for statistical analysis. The number of pruritus episodes was compared among baseline, saline and the different concentrations of each substance. The results showed that dogs did not have a significant increase in pruritic behaviour above baseline or saline after injection of any of the investigated substances (generalized linear model; P  = 0.23).     

Technique for repeated collection of blood that has just perfused the pineal gland of sheep

A long catheter was inserted into the superior sagittal sinus of sheep and was maneuvered to the level of the rectus sinus. The catheter was then secured to the head, neck, and shoulder of the animal. The distal end of the catheter was connected to a 3-way valve through which blood samples were collected and heparin was injected. Blood loss during surgery was minimal; recovery was quick and complete. The simple surgical technique enabled the collection of blood that has just perfused the pineal gland.