Multiple congenital ocular anomalies in three related litters of Jack Russell Terrier puppies.

OBJECTIVE: To describe multiple congenital ocular anomalies in three litters of Jack Russell Terrier puppies. ANIMALS STUDIED: Seven purebred Jack Russell Terrier puppies from three related litters and their four parents. PROCEDURES: Medical records of the puppies and their parents were evaluated. All dogs underwent a complete ophthalmic examination, followed by bilateral ocular ultrasonography in two of the puppies with complete corneal opacity. One eye from an affected puppy was subjected to histopathology. A complete database of pedigrees was built, and individual inbreeding was evaluated. RESULTS: The most commonly diagnosed ocular anomalies in the puppies were: various anomalies of the fundus (12/14 eyes); microphthalmia (10/14 eyes); sclerocornea (8/14 eyes); and persistent pupillary membranes (7/14 eyes). Six out of seven puppies had at least two ocular abnormalities, and only one puppy was normal. Four out of seven puppies had sclerocornea, a particular corneal opacity to date described only in Spanish Podenco dogs. No ocular abnormalities were found in the parents examined (4/4). Analysis of the pedigrees showed that all the puppies and two parents were inbred, and the individual values of the inbreeding puppies were greater than 6.25% in two litters. CONCLUSIONS: Inbreeding with closely related Jack Russell Terriers may result in severe congenital eye abnormalities in puppies.

Combined immunohistochemical protocols to differentiate macrophages within the mononuclear-phagocyte system.

BACKGROUND: The "mononuclear phagocyte system" (MPS) refers to dispersed mononuclear monocytes and macrophages and is used to distinguish them from polymorphonuclear cells. The term "histiocyte" indicates large cells with voluminous granulated cytoplasm, sometimes containing engulfed particles, recognized as fully differentiated end cells of the MPS. Dendritic cells (DC) represent another diversified population whose inclusion in the MPS is still debated. The diverse cells of the MPS cannot all be characterized by single antigen markers or unique functions expressed at all stages of cell differentiation or activation. Nevertheless, in a diagnostic setting, their reliable identification plays a major role when a specific therapy must be established. Understanding the heterogeneity among MPS cell populations is indeed relevant to define different therapeutic approaches that can range from the use of antibiotics to immunomodulatory agents. For this reason, we attempted to establish a protocol to reliably identify the proportion of macrophages within the mononuclear phagocyte system in a tissue and/or in a given inflammatory population. METHODS: the Tafuri method was used in different double immunofluorescence protocols using an anti-Iba-1, anti-MAC387, and anti-CD11b-CD68-CD163-CD14-CD16 antibody. RESULTS AND DISCUSSION: in normal canine skin the anti-Iba-1 antibody stained an epidermal cell population (i.e. Langerhans cells) and scattered cells within the dermal compartment. MAC387 was unable to stain cells containing Leishmania amastigotes in leishmaniasis-diagnosed samples as the anti-CD11b-CD68-CD163-CD14-CD16 antibody did. By using a combination of staining protocols to differentiate macrophages within the whole histiocytic infiltrate we validated the use of a cocktail of rabbit monoclonal antibodies raised against CD11b, CD68, CD163, CD14, CD16 to stain skin macrophages.

Association between waste management and cancer in companion animals.

BACKGROUND: Increased cancer rates have been documented in people residing in areas around Naples characterized by illegal dumping and incineration of waste. HYPOTHESIS: Risk of cancer in dogs and cats is associated with waste management. ANIMALS: Four hundred and fifty-three dogs and cats with cancer and 1,554 cancer-free animals. METHODS: Hospital-based case-control study in Naples (low danger) and nearby cities having a history of illegal waste dumping (high danger). Odds ratio (OR) between high- and low-danger areas was calculated for all tumors and various malignancies in dogs and cats. RESULTS: An increased risk for cancer development was identified in dogs but not in cats residing in high-danger areas (OR: 1.55; 95% confidence interval: 1.18-2.03; P < .01). A 2.39-fold increased risk of lymphoma (P < .01) accounted for the greater tumor frequency in dogs residing in high-danger areas. The risk of mast cell tumor and mammary cancer did not differ in dogs residing in high- or low-danger areas. CONCLUSIONS AND CLINICAL IMPORTANCE: Waste emission from illegal dumping sites increases cancer risk in dogs residing in high-danger areas. An increased prevalence of lymphoma has been previously recognized in humans living close to illegal waste dumps. Thus, epidemiological studies of spontaneous tumors in dogs might suggest a role for environmental factors in canine and human carcinogenesis and can predict health hazards for humans.

Effect of a hydrocolloid dressing on first intention healing surgical wounds in the dog: a pilot study.

OBJECTIVES: To evaluate the efficacy of a hydrocolloid dressing for the treatment of surgical wounds in dogs. METHODS: Six healthy young female dogs of medium size and different breed underwent ovariohysterectomy. Histological evaluation was performed on biopsies taken from the edges of the wounds at day 7. The dressing was applied on one half of the wound according to manufacturer's instructions; the second half served as control. Biopsy specimens were fixed in a 10% formalin buffered solution pH 7.4, paraffin embedded and stained with haematoxylin and eosin. For clinical assessment, the presence and quality of exudate, erythema of the surrounding area, swelling and correct apposition of the wound margins were evaluated. RESULTS: The hydrocolloid dressing was easy to use. The clinical quality of the treated skin wounds was superior to the non-treated ones. Comparison of histological features between treated and untreated wounds showed a more regular organisation of the granulation tissue in the treated wounds, with fibroblasts being aligned parallel to the overlying epidermis. The number of inflammatory cells and the extension of granulation tissue were less prominent and less widespread in treated compared to untreated wounds. CONCLUSION: The dressing performed very well in terms of adhesiveness and flexibility. It was useful in the management of surgical wounds to avoid contamination and ameliorate the epithelialisation rate and granulation tissue morphology of the surgical scar.

Anaplastic and aggressive subcutaneous sarcoma in a seven-month-old dog.

A seven-month-old female, Italian hound which was presented with anorexia, dyspnoea and weight loss showed two subcutaneous masses at physical examination. Radiographs showed multiple opacities in the lungs, thorax, liver and spleen, and cytology showed discrete pleomorphic cells, with variable nuclear : cytoplasmic ratio, foamy cytoplasm and round to oval nuclei. Incisional biopsy histology showed the infiltrative proliferation of highly pleomorphic spindle to roundish large cells, discrete or arranged in a storiform pattern, with scattered multinucleated giant cells. Immunohistochemistry exhibited strong positivity for vimentin and mild labelling for alpha-smooth muscle actin and lysozyme; other mesenchymal or histiocytic lineage markers stained negatively. Because of the poor prognosis, the owner elected euthanasia. Post-mortem examination confirmed massive metastatic spread. Cytology, histology and immunohistochemistry suggested the diagnosis of anaplastic sarcoma with giant cells, although disseminated histiocytic sarcoma was a reliable differential diagnosis. The authors underline the difficulties in definitively categorising poorly differentiated sarcomas, even if a large panel of markers is applied.

Osteopontin expression in healing wounds of horses and in human keloids.

REASONS FOR PERFORMING STUDY: Convincing evidence shows that persistent or excessive expression of osteopontin (OPN) is linked to fibroproliferation of various organs in laboratory animals and in man, such that its downregulation is a logical therapeutic objective. OBJECTIVES: To investigate OPN expression in an equine model of wound healing and in clinical specimens of equine exuberant granulation tissue and human keloids in an effort to better understand the contribution of this protein to inflammation-associated skin fibrosis. STUDY DESIGN: Description of gene and protein expression in an experimental equine model of wound healing and clinical specimens in horse and man. METHODS: Osteopontin gene expression was evaluated by quantitative PCR, while protein expression was investigated by means of immunohistochemical staining. RESULTS: Quantitative PCR showed that the OPN gene is expressed in normal intact skin of horses and continues to be expressed during the wound-healing process. An increase in gene expression was observed throughout the phases of wound healing, with a final decrease at wound closure. The protein was not detected in normal skin. Keratinocytes in wound-edge samples did not express the protein, whereas dermal immunoreactivity was confined to inflammatory cells. Healed wounds were devoid of staining. Equine exuberant granulation tissue showed immunoreactivity of the surrounding epidermis, infiltrating neutrophils, mononuclear cells, endothelial cells and fibroblasts. Human keloids showed OPN immunoreactivity throughout the epidermis as well as in mononuclear cells and scattered fibroblasts. CONCLUSIONS: Immunohistochemical data show a different pattern of expression between normally healing and fibrotic wounds (exuberant granulation tissue and keloids), thus suggesting a role in fibroproliferation in horses and man.

Abnormal regulation of the hypothalamo-pituitary-adrenal axis in the genetically obese fa/fa rat.

Adrenalectomy has been shown to reverse most facets of the syndrome of the genetically obese fa/fa rat. However, a detailed analysis of the hypothalamo-pituitary-adrenal (HPA) axis in these animals is lacking. In the present study, morning corticosteronemia was higher in obese rats of both sexes than in lean ones, whereas evening corticosteronemia was higher only in obese male rats. The HPA axis was further investigated using stressful stimuli. Immobilization, ether, and cold stresses resulted in greater corticosterone levels in obese than in lean animals. These abnormalities consisted in upward shifts of the corticosterone response in obese females and absolute increases in that of obese males, indicating that such alterations were more pronounced in obese male than obese female rats. Due to this, the putative origin of the increased corticosterone output of obese rats was studied in males. Greater levels of ACTH were reached in obese than in lean rats when submitted to a cold stress (6 C). Dexamethasone produced a complete suppression of corticosterone output in both lean and obese rats. During the recovery from such suppression, corticosterone levels rose to higher values in obese than in lean rats. This observation together with the greater cold-induced ACTH output in obese rats suggest that the increased activity of the HPA axis of these animals is of central origin. Whatever its precise etiology within the central nervous system, it is proposed that the increased HPA axis activity in obese rats and its resultant hypercorticism play a role in the establishment and maintenance of their syndrome.

Changes in the hypothalamo-pituitary-adrenal axis of genetically obese fa/fa rats: a structural, immunocytochemical, and morphometrical study.

Most metabolic disorders of genetically obese Zucker rats are reversed by adrenalectomy and are restored by corticosterone treatment, thus suggesting that a functional hypercorticosteronemic state is involved in the pathogenesis of the obesity syndrome in fa/fa rats. However, the hormone content and morphology of the hypothalamo-pituitary-adrenal axis of this animal model have to our knowledge not yet been described. We, thus, investigated morphologically and morphometrically the hypothalamic regions involved in CRF synthesis and secretion in male fa/fa rats. To ascertain if the brain is selectively or uniformly affected, we studied the main nuclei of the lateral and mediobasal hypothalamus, i.e. arcuate, lateral hypothalamic, and ventromedial nucleus and the parvicellular portion of the paraventricular nucleus. Moreover, after immunocytochemical labeling, we analyzed densitometrically the CRF-bearing axons of the median eminence and the ACTH-containing cells of the anterior and intermediate lobe of the pituitary gland. Finally, we investigated the adrenal glands by qualitative light microscopy. In fa/fa rats most hypothalamic nuclei were structurally changed. Furthermore, hypothalamic CRF and anterior pituitary ACTH contents as well as adrenal weight were increased, the zona fasciculata of the adrenal cortex was hypertrophic, and the ACTH content of the intermediate lobe was reduced. In conclusion, our results demonstrate that the obesity syndrome in genetically obese fa/fa rats is associated with lesions of the hypothalamo-pituitary-adrenal axis consistent with hyperadrenocorticism due to hyperactivity of the whole adrenal axis. Alterations also occur in the hypothalamic nuclei controlling glycemia, insulinemia, and circadian corticosterone secretion.

Regional distribution of lesions in the central nervous system of cats infected with feline immunodeficiency virus.

Neuropathological examination of the central nervous system of 13 naturally and 13 experimentally feline immunodeficiency virus (FIV)-infected cats revealed diffuse gliosis of gray and white matter and vacuolar myelinopathy in a large proportion of infected animals, sometimes associated with lymphocytic meningitis. Multinucleated giant cell formation, the hallmark of multifocal giant cell encephalitis in HIV infection, was never observed. Morphometric analysis confirmed a marked increase of GFAP reactivity in infected cats. Gliosis was mainly present in cortical structures of frontal, parietal, and occipital lobes. Only one naturally infected animal evidenced clinical symptoms of neurological damage. This study confirms that FIV provides an interesting model for studying HIV-induced cortical and subcortical brain pathology believed to be the cause of the neurological manifestations frequently observed in AIDS patients.

The reduction of circulating growth hormone and prolactin in streptozocin-induced diabetic male rats is possibly caused by hypothalamic rather than pituitary changes.

To gain further information on diabetes-related disorders in the somatotrophic and lactotrophic axes, we undertook a functional, morphometrical and densitometrical study of the arcuate nucleus (AN), median eminence (ME) and anterior pituitary gland of adult male rats one month after streptozocin-induced diabetes (STZ-D). The basal secretory activity of somatotrophs and lactotrophs was tested by the reverse haemolytic plaque assay (RHPA) and plasma GH and prolactin (PRL) levels were determined by RIA. The number of GH-releasing factor (GRF)-labelled axons and the amount of axonal tyrosine hydroxylase (TH)-immunoreactivity increased in STZ-D. There were no significant differences in any of the other densitometrical measurements performed on GRF-, somatostatin-, thyrotropin-releasing hormone- and TH-labelled ME axon cross-sections as well as those on tuberoinfundibular-dopaminergic neurones of the AN in STZ-D compared with control rats. Plasma GH and PRL levels and measurements on anterior pituitary GH- and PRL-labelled structures were decreased in STZ-D. However, the GH and PRL plaque areas were increased after RHPA implying that the secretory capacity of somatotrophs and lactotrophs was not impaired. Taken together, these results suggest that the accumulated GRF in the ME is due to reduced GRF release. This could account for the reduced amplitude and/or frequency of GH secretory pulses. The increased axonal TH-immunoreactivity may indicate an increased dopamine synthesis. If coupled to increased release this could, in turn, be partly responsible for the reduced plasma and anterior pituitary PRL concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

Detection of feline immunodeficiency virus p24 antigen and p24-specific antibodies by monoclonal antibody-based assays.

A panel of monoclonal antibodies (mAbs) detecting distinct B-cell epitopes on p24 core viral protein of feline immunodeficiency virus (FIV) were employed to develop immunoassays to measure p24 concentration in culture and serum samples, to localize p24 in FIV-infected cells and tissues, and to detect anti-p24 antibodies in cat sera. In its optimized configuration the p24 capture assay detected as little as 0.25 ng/ml of protein. The assay was found at least as sensitive as the reverse transcriptase activity assay in FIV-infected lymphocyte cultures and proved capable of detecting p24 antigen in acid pretreated sera from a high proportion of FIV-infected cats. The mAbs were also successfully used to detect the p24 antigen in permeated FIV-infected cells by flow cytometry and in tissue sections from FIV-infected cats by immunohistochemical staining. Anti-p24 antibodies in FIV-infected cat sera were assayed by a competitive capture ELISA which readily identified occasional false positive results provided by a standard ELISA using purified whole FIV-coated wells.

Measurement of elastic resisting forces of intraocular haptic loops of varying geometrical designs and material composition.

The relationship between experimentally induced intraocular lens (IOL) haptic deformation and resulting elastic haptic counter-resisting forces measured by electronic dynamometry was examined for 34 different IOL haptics of varying material composition and geometrical designs. Poly(methyl methacrylate) (PMMA) and polypropylene loops of similar geometry did not fundamentally differ from one another, although lenses of differing geometry behaved differently. Unlike PMMA and polypropylene loops, soft haptics of poly-HEMA and silicone rubber demonstrated a larger elastic resistance force to the same degree of deformation. This was based upon design characteristics of the lenses and not upon intrinsic properties of the materials, which would have produced the opposite result. By comparative analysis of these dynamometer measurements and considerations of the lens design and elastic properties (including memory) of the component materials, we can calculate the stresses upon the zonular and capsular bag structures during and after IOL implantation.

Renal involvement in feline immunodeficiency virus infection: p24 antigen detection, virus isolation and PCR analysis.

Renal alterations characterized morphologically by glomerular and tubulo-interstitial lesions and clinically by a heavy proteinuria and sometimes by renal failure are frequent in feline immunodeficiency virus (FIV) infected cats. To investigate the possible role of local FIV replication in the genesis of this renal damage, renal tissues of 15 consecutive naturally infected and five non-infected cats were examined for traces of the virus by immunohistochemistry, using a monoclonal anti-p24 antibody in a streptavidin-biotin peroxidase labeled system, cultivation and polymerase chain reaction (PCR). Tubular epithelial cells as well as scattered interstitial inflammatory and glomerular cells were positive for p24 antigen in 13 cats. Viral isolation was successful in seven cats, and FIV gag DNA and RNA sequences were detected in 14 and five cats, respectively. Control cats were constantly negative. Although not conclusive, these results suggest that a direct role of FIV in the induction of the renal damage observed in infected animals is possible.

Prevalence of feline immunodeficiency virus and other retroviral infections in sick cats in Italy.

Two hundred and seventy-seven sick pet cats living in Italy were tested for antibodies to feline immunodeficiency virus (FIV) and for feline leukemia virus (FeLV) antigen. Overall, 24% of the cats resulted positive for anti-FIV antibody and 18% for FeLV antigen. FIV was isolated from the peripheral mononuclear blood cells of ten out of 15 seropositive cats examined and from one out of eight saliva samples. No FIV isolations were obtained from six serum samples cultured. Feline syncytium forming virus (FeSFV) could be isolated from blood and/or saliva in ten out of 11 FIV seropositive cats examined, in six out of nine FeLV antigen positive cats, in two cats found positive for both infection markers, and in three out of 11 cats negative for both markers. Thus, the probability of isolating FeSFV was enhanced by infection with other exogenous retroviruses.

Renal involvement in mice experimentally infected with Toxocara canis embryonated eggs.

Histological examination of kidneys from mice experimentally infected with Toxocara canis embryonated eggs demonstrated the presence of a segmental or diffuse mesangioproliferative glomerulonephritis. Immunohistochemical studies established that renal alterations were associated with glomerular deposits of IgG, IgM and third component of complement (C3). These findings suggest that an immunomediated mechanism might possibly be involved in the genesis of kidney damage observed in mice infected with T. canis embryonated eggs.

Malignant lymphoma associated with experimentally induced feline immunodeficiency virus infection.

A malignant low-grade B-cell lymphoma, primarily in the kidney, is described in a specific-pathogen-free cat experimentally infected with feline immunodeficiency virus (FIV) and free of feline leukaemia virus. At the time of diagnosis the cat showed a marked reduction of circulating CD4+ T lymphocytes, was 2 years old, and had been infected for 18 months. FIV was isolated both from peripheral blood mononuclear cells and the neoplastic tissue. DNA of FIV gag gene was detected in several specimens, including the neoplastic tissue. Even if they do not demonstrate a direct role for virus promotion of lymphomas, these and previous observations indicate that B-cell malignant lymphoma might be associated with FIV infection as reported for human and simian immunodeficiency virus infections.

Feline cutaneous phaeohyphomycosis due to Cladophyalophora bantiana.

A case of feline cutaneous phaeohyphomycosis due to Cladophyalophora bantiana is described. The cat was presented with breathing difficulty and a swollen, ulcerated nodule on the dorsal nose and left nostril. Histological examination of the nodule revealed a cystic granulomatous dermatitis characterised by neutrophils, macrophages and giant cells. Pigmented, yeast-like fungus cells and hyphal elements were easily identified in haematoxylin-eosin stained tissue sections. Cladophyalophora bantiana was isolated from a tissue specimen. This organism, primarily known to cause cerebral infection in humans and cats, only rarely causes cutaneous infection. Despite anti-fungal chemotherapy two relapses occurred. The cat was feline immunodeficiency virus- and feline leukemia virus-negative and even if the owner was unaware of trauma, the hypothesis of wound contamination is the most likely.

Unilateral hydrocephalus in a wild European brown hare (Lepus europaeus).

Macroscopic and histological study of a case of unilateral hydrocephalus in a young wild European brown hare (Lepus europaeus) is reported here. Morphological changes were mostly massive dilatation of the left lateral ventricle, atrophy of the cortex and a striking reduction of the corresponding white matter. Lymphocytic cell infiltrates and hemosiderin-laden macrophages in the choroid plexus and meninges also were observed. Although the exact cause of the lesions was not found all findings suggested a hydrocephalus of possible traumatic, infectious or congenital hypoplasia origin.

Lentivirus infection in an African lion: a clinical, pathologic and virologic study.

In May 1991, clinical, pathologic, and virologic investigations were carried out on an 8-yr-old male lion (Panthera leo), with recurrent infections, in captivity with two lionesses in the Zoological Garden of Pistoia, Tuscany, Italy. The lion had severe pneumonia, neutropenia, thrombocytopenia, and an increase in blood urea nitrogen and creatininemia; in spite of therapy, it died within 3 months. At necropsy, the animal had a lymphoma and other lesions similar to those described in feline immunodeficiency virus-infected cats. We identified FIV gag-sequence using PCR amplification of lymph node tissues.

Survey of canine and feline follicular tumours and tumour-like lesions in central Italy.

Between January 1985 and June 1997, a total of 4005 skin biopsies were received from dogs and 898 from cats. Follicular tumours and tumour-like lesions together represented 10.4 per cent and 8.1 per cent of all skin tumours in the dog and cat, respectively. The prevalence of tumour-like lesions, such as follicular and dermoid cysts, dilated pore and focal adnexal dysplasia, was highest, representing 41.2 per cent and 68 per cent of all follicular lesions in dogs and cats, respectively. In the dog, follicular tumours were distributed as follows: trichoblastoma (25.6 per cent of all tumours and tumour-like lesions), infundibular keratinising acanthoma, (14 per cent), pilomatricoma (13 per cent), trichoepithelioma (3.9 per cent) and tricholemmoma (2.3 per cent). In the cat, the distribution was 26 per cent for trichoblastoma, 4 per cent for trichoepithelioma and 2 per cent for pilomatricoma. Tumour-like lesions and infundibular keratinising acanthoma in the dog were mostly located on the trunk, trichoblastoma and tricholemmoma on the head, and pilomatricoma on the neck. In the cat, both tumour-like lesions and trichoblastoma were frequently present on the neck and head.