Immunohistochemical Study of Four Fish Tumors.

The present study supports the usefulness of ancillary techniques, such as immunohistochemistry, as a valid diagnostic tool in the field of fish oncology. The immunohistochemical patterns observed in four neoplasms on four individual teleosts belonging to different species are described. Cytokeratin, vimentin, actin, S100, calretinin, and Melan-A antibodies were used. Diagnoses of papilloma in a Bream Abramis brama, fibroma in a Sand Steenbras Lithognathus mormyrus, schwannoma in a Crucian Carp Carassius carassius, and melanoma in a spontaneously inbred Xiphophorus hybrid were made. Diagnosis of tumors in fish is not always easy to carry out, and the tool provided by antibodies used on mammalian tissue is essential for obtaining definitive, unambiguous, and inexpensive identification.

Multicentric infiltrative lipoma in a farmed Mediterranean seabass Dicentrarchus labrax: a pathological and biochemical case study.

A tumour diagnosed as multicentric infiltrative lipoma affecting a single farmed seabass is described. The fish had 3 masses on the lateral side of its back, deforming the skin surface. The masses showed a tendency to invade the underlying musculature. Histologically, the neoplasm consisted of differentiated adipocytes. Biochemically, the neoplastic tissue showed lower values of monounsaturated fatty acids and higher values of polyunsaturated fatty acids compared with adjacent normal muscular tissue, particularly of the n3 series, such as eicosapentanoic (C20:5n3) and docosahexanoic (C22:6n3) acids. Data obtained suggest a metabolic disturbance in the lipid component of the muscular tissue metabolic pathway, which could be the starting point to promote lipoma formation. This is the first report of lipoma in Mediterranean seabass.

Nuclear morphometry in relation to lymph node status in canine mammary carcinomas.

The assessment of nuclear area and nuclear shape by morphometric analysis, has been investigated in 40 canine mammary carcinomas in relation to their metastatic behaviour to regional lymph-nodes. The tumours were reviewed by two experienced pathologists blinded regarding their lymph-node status, and were classified according to the histogenetically based criteria suggested by Benjamin et al. (1999). Twenty of these tumours showed lymph-node metastases (node-positive), and the other twenty were node-negative. Node-positive tumours included 6 simple adenocarcinomas, 10 ductular carcinomas, 2 anaplastic carcinomas and 2 carcinomas in mixed tumours; node-negative tumours included 18 adenocarcinomas %96, 10 simple adenocarcinomas, 8 complex adenocarcinomas %96, and 2 carcinomas in mixed tumours. Node-positive tumours showed MNA and mean SDA values significantly higher (p<0.001) than node-negative carcinomas. Data of this study, seems to confirm the importance of an histogenetically based classification in canine mammary tumours, also suggesting that morphometry may increase our prognostic performances allowing a reproducible method for detecting individual tumours with higher metastatic potential.

Incomplete caudal duplication in a puppy: gross and radiological observations.

Caudal duplication is a rare type of conjoined twinning. The aim of this case report is to describe a case of caudal duplication in a male crossbreed puppy. The puppy was macroscopically and radiographically examined after death. External features included a supernumerary limb projecting from the perineum, complete lack of tail, anal atresia, double penis and absence of scrotal sacs. Internal examination showed anomalies involving the intestine and the urinary system. At x-ray examination, the supernumerary limb showed features similar to that of the normal right hindlimb but showed absence of fibula and tibia and presence of three metatarsi and phalanges. The authors discuss the pathogenic mechanisms of this condition, infrequently reported in veterinary practice, pointing out the importance of embryonic duplications commonly associated with dystocia.

Cloricromene, a coumarine derivative, protects against collagen-induced arthritis in Lewis rats.

1. The aim of the present study was to investigate the effects of cloricromene, a coumarine derivative, in rats subjected to collagen-induced arthritis. 2. Collagen-induced arthritis (CIA) was induced in Lewis rats by an intradermal injection of 100 microl of the emulsion (containing 100 microg of bovine type II collagen) (CII) and complete Freund's adjuvant (CFA) at the base of the tail. On day 21, a second injection of CII in CFA was administered. 3. Lewis rats developed an erosive hind paw arthritis when immunized with CII in CFA. Macroscopic clinical evidence of CIA first appeared as peri-articular erythema and oedema in the hind paws. The incidence of CIA was 100% by day 27 in the CII challenged rats and the severity of CIA progressed over a 35-day period with radiographic evaluation revealing focal resorption of bone together with osteophyte formation in the tibiotarsal joint and soft tissue swelling. 4. The histopathology of CIA included erosion of the cartilage at the joint margins. Treatment of rats with cloricromene (10 mg kg(-1) i.p. daily) starting at the onset of arthritis (day 23), delayed the development of the clinical signs at days 24 - 35 and improved histological status in the knee and paw. 5. Immunohistochemical analysis for iNOS, COX-2, nitrotyrosine and for poly (ADP-ribose) synthetase (PARS) revealed a positive staining in inflamed joints from collagen-treated rats. The degree of staining for iNOS, COX-2, nitrotyrosine and PARS were markedly reduced in tissue sections obtained from collagen-treated rats, which had received cloricromene. 6. Radiographic signs of protection against bone resorption and osteophyte formation were present in the joints of cloricromene-treated rat. 7. This study provides the first evidence that cloricromene, a coumarine derivative, attenuates the degree of chronic inflammation and tissue damage associated with collagen-induced arthritis in the rat.

Comparison of nuclear morphometric parameters in cytologic smears and histologic sections of spontaneous canine tumors.

BACKGROUND: Nuclear morphometry may provide useful diagnostic and prognostic information for neoplasms in animals. Most available data have been obtained from histologic sections. Nuclear morphometry of cytologic smears may provide important preoperative information. OBJECTIVE: The goal of this study was to compare nuclear morphometric parameters in cytologic smears and histologic sections from spontaneous canine tumors. METHODS: Mean nuclear area (MNA), mean nuclear perimeter (MNP), mean nuclear form factor (FF; nuclear perimeter(2)/4pi nuclear area) and their respective SDs were assessed by image analysis of both hematoxylin and eosin-stained histologic sections and May-Grünwald-Giemsa-stained cytologic smears from the same case in 20 spontaneous canine tumors of different histogenesis. The above parameters were selected as being the best morphometric tools for measuring variation in shape and size in cells after neoplastic transformation. Data were compared by ANOVA with P<.01 considered significant. RESULTS: There was a significant difference between histologic and cytologic specimens for MNA, MNP, and their SDs. Only the differences between FF and the SD of FF were not statistically significant. CONCLUSIONS: Only nuclear morphometric data related to nuclear shape and nuclear shape variability are comparable between histologic and cytologic specimens. Nuclear area and perimeter may be affected by the different fixation and smear preparation techniques used in histology and cytology.

A rare case of deradelphus cephalo-thoracoomphalopagus in lamb.

Male cross-breed lamb conjoined twins were sent for examination. The twins came from a farm located in the outskirts of Palermo. The twins were spontaneously delivered and found dead by the farmer. X-ray examination and necropsy were performed. The deformity was identified as deradelphus cephalo-thoracoomphalopagus. This condition has never been reported in veterinary literature. Our case reports of male conjoined twins characterized by two separated hearts with their own pericardial sacs and two separated livers. These findings represent a rare condition in conjoined twinning.

A case of unilateral pelvic limb adactyly in a puppy dog.

A case of unilateral hindlimb adactyly is described in a 3-month-old female Pointer dog. Clinical and radiographic findings are described. Adactyly or transverse hemimelia is a rare condition in most animal species. In dogs, this condition has been reported only three times as a deformity of the forelimb. To the authors' knowledge, the congenital pelvic limb deformity described here is the first case documented in a dog.

Mast cells in canine mammary gland tumour: number, distribution and EPOR positivity.

Erythropoietin (EPO)-mediated mitogenic and anti-apoptotic effects involve all the cells expressing functional receptors for EPO (EPOR), as demonstrated by in vitro and in vivo studies. EPO shows pleiotropic effects and acts as an endogenous mediator of adaptive tissue response to metabolic stress protecting tissues from different injuries. Recently, the EPO/EPOR complex has been identified in several neoplastic cell lines and solid tumours. In this study, the authors investigated the mast cells (MCs) number, distribution and their immunoreactivity for EPOR in normal, dysplastic and neoplastic canine mammary gland. The results showed that MCs were more numerous in displastic glands compared with normal and neoplastic glands. As far as the EPOR immunoreactivity is concerned, we did not observe MCs reaction on cancer, in contrast with previously published data where epithelium of neoplastic gland showed an increase in EPOR expression along with the neoplastic progression. Overall, our results might be suggestive for MCs role in oncogenesis and offer new insight regarding to the expression of EPOR in mammary gland cancer in dog.

Deradelphous cephalothoracopagus in kittens.

Cephalothoracopagus is a very rare form of conjoined twins and is characterized by fusion of heads and thoraxes with two separate spines, limbs and pelves. The aim of this study was to describe a case of female cephalothoracopagus kitten puppy. The most important gross findings involved the external body and some of the internal organs. Radiological features revealed main developmental abnormality of the head, spines and thorax. Authors discuss the pathogenic mechanisms of this condition, infrequently reported in veterinary practice, pointing out the importance of embryonic duplications commonly associated with dystocia.

A case of conjoined cephalopagus twinning in an ostrich (Struthio camelus).

Conjoined twinnings have been reported in most domestic animal species and in some avian species. Cases of conjoined twins have not been reported in the ostrich so far. A hybrid Blue neck x African black male ostrich conjoined twinning was born at the end of artificial egg incubation and died spontaneously 24 h after the hatching. It was frozen and sent to the Unit of Veterinary Pathology of the University of Messina for gross examination. The most important gross findings involved the external body and most of the internal organs. On the basis of the duplication, the conjoined twins were classified as a cephalopagus. Radiological features included: development of one head containing a single brain, two spinal cords, deviated vertebral columnae with fusion of the two first cervical vertebrae. In one twin, the synsacrum was absent as well as portions of the vertebral column. Grossly, both twins showed two upper and lower limbs each. The gastro-enteric apparatuses of the twins were not completely developed and fused at different levels. One liver and one heart localized in the centre of the conjoined twins were observed. The authors conclude that the possible causes of the malformation could be related to a genetic factor.

Erythropoietin receptor expression in canine mammary tumor: an immunohistochemical study.

Erythropoietin (EPO) is a cytokine primarily involved in the regulation of the erythropoiesis. Recently, it has been demonstrated that EPO and its receptor (EPOR) are expressed in several neoplastic cell lines and solid tumors. Furthermore, in vitro and in vivo studies have shown that EPO could promote human breast carcinoma growth by means of the binding with its receptor, although a clear function for EPO in this setting has not been yet established. While the human medical literature has been accumulating strong evidence on EPO's role in oncogenesis, to date, there are no veterinary reports focusing on such an issue. The aim of the present study was to investigate the immunohistochemical expression of EPOR in canine mammary gland dysplastic and neoplastic lesions. Our results show a weak to moderate EPOR expression in dysplastic glands, being immunoreactivity enhanced as the lesion shows an increasing malignant pattern. On the basis of these findings, this study describes, for the first time, the evidence for EPOR expression in canine mammary gland tumor and suggests a feasible EPO's role for canine mammary tumor progression.

Diprosopiasis in a lamb. A case report.

Conjoined twinning has been reported in most of the domestic animal species. Among them, sheep have the highest incidence of craniofacial defects. A live male crossbreed dystocic two-headed lamb was delivered from a 2-year-old Pinzerita sheep after first mating. After 40 h of life, the lamb spontaneously died. The most important gross findings involved the head, whereas the examination of different organ and tissue sections did not reveal remarkable histomorphological changes. The lamb was classified as a conjoined twinning and, on the basis of the facial duplication, as a diprosopus tetraophtalmus.

Prolactin changes after administration of agonist and antagonist dopaminergic drugs in puerperal women.

Prolactin (PRL) is an anterior pituitary hormone which plays a large part in the reproductive function of mammals. Its only well-documented effect in humans is that of initiating and maintaining lactation. Among hypothalamic neurotransmitters regulating the anterior pituitary function, dopamine (DA) is currently considered to correspond to the PRL-inhibiting factor. The central control mechanisms which induce high PRL levels in puerperal women are not well understood. To study DA tonus in puerperium we tested plasma PRL levels in different groups of puerperal subjects (6 per group) after acute administration of direct or indirect DA agonists or placebo: DA, L-dopa (a DA precursor), L-dopa plus carbidopa (a peripheral dopa-decarboxylase inhibitor), nomifensine (a DA-releasing and blocking or reuptake agent) and amphetamine (a DA releaser). The same tests with the same drug doses were performed on groups of healthy volunteers. A consistent reduction in plasma PRL levels after both direct and indirect DA agonist drugs compared to placebo was evident in puerperal and in control women. A different trend was only observed with the use of DA and amphetamine in puerperal subjects, who, unlike controls, failed to show a rebound in plasma PRL levels after the termination of drug infusion. These findings support the view that the inhibitory control of tuberoinfundibular neurons over PRL secretion is maintained in puerperium and changes in the affinity of DA receptors are related to the endocrine milieu which occurs during gestation.

Mucopolysaccharidosis VI in a Siamese/short-haired European cat.

A 3-year-old Siamese/short-haired European cat was referred for clinical disease characterized by dwarfism, facial dysmorphia, paralysis, small and curled ears, corneal clouding and large areas of alopecia. X-ray examination showed multiple bone dysplasia. On the basis of clinical features a form of mucopolysaccharidosis was suspected. The cat, killed at the owner's request, presented several severe skeletal deformities such as long caudal limbs, enlarged thorax with sunken breastbone, vertebral ankylosis in many spinal segments and visceral involvement. Histologically, the cat showed diffuse vacuolization and enlargement of cells in cartilage, bone and visceral organs. Ultrastructurally, membrane-bound vacuoles were filled with fibrillar and fluffy-material or concentrically whorled lamellae. Arylsulphatase B activity was 3.24 nm/mg/h in the affected cat and 30.6 in a normal age-matched control (NC). The L-iduronidase activity was slightly increased. Quantitation of total glycosaminoglycans (GAGs) revealed a 4.5-fold increase in the affected cat as compared with NC, while electrophoretic run of specific GAGs [chondroitin sulphate (CA); hyaluronan (HA); heparan sulphate (HS); dermatan sulphate (DS); keratan sulphate (KS)] performed on a cellulose acetate sheet, showed a striking increase in the DS band. On densitometric analysis of the electrophoretic run stained with Alcian Blue 8GX, the absorption of DS was eight-fold increased as compared with NC. The clinical and morphological features, and the biochemical findings, were consistent with the diagnosis of feline mucopolysaccharidosis VI.

Plasma and cyst fluid levels of delta 5 and delta 4 steroid hormones in women with gross cystic breast disease.

delta 5 and delta 4 steroid levels were studied in the plasma and cyst fluid of women with gross cystic breast disease (GCBD). In luteal phase a significant increase in plasma levels (mean +/- SEM) of DHA (11.2 +/- 2.4 ng/ml), DHAS (1.45 +/- 0.6 micrograms/ml) and cortisol 277 +/- 15.7 ng/ml) was found; in follicular phase the mean levels were 4.09 +/- 0.47 ng/ml for DHA, 0.65 +/- 0.08 microgram/ml for DHAS and 190 +/- 46.3 micrograms/ml for cortisol. The DHA/DHAS and cortisol/androstenedione ratios were significantly higher in the plasma and lower in the cyst fluid of GCBD patients, than in the plasma of controls; the androstenedione/DHA ratio was higher in the cyst fluid than in the plasma of controls. The hormonal situation of the GCBD patients thus differed from that of the controls both in the plasma and cyst fluid, particularly as regards the delta 5 steroids.

Beneficial effects of tempol, a membrane-permeable radical scavenger, in a rodent model of collagen-induced arthritis.

OBJECTIVE: To investigate the effects of tempol, a membrane-permeable radical scavenger, in rats with collagen-induced arthritis (CIA). METHODS: CIA was induced in Lewis rats by intradermal injection of 100 microl of an emulsion of 100 microg of bovine type II collagen (CII) in complete Freund's adjuvant (FCA) at the base of the tail. On day 21, a second injection of CII in FCA was administered. RESULTS: Lewis rats developed an erosive arthritis of the hind paws when immunized with CII in FCA. Macroscopic evidence of CIA first appeared as periarticular erythema and edema in the hind paws. The incidence of CIA was 100% by day 27 in the CII-challenged rats, and the severity of CIA progressed over a 35-day period. Radiographs revealed focal resorption of bone, with osteophyte formation in the tibiotarsal joint, and soft tissue swelling. The histopathologic features included erosion of the cartilage at the joint margins. Treatment of rats with tempol (10 mg/kg/day intraperitoneally) starting at the onset of arthritis (day 23) delayed the development of the clinical signs on days 24-35 and improved the histologic status of the knee and paw. Immunohistochemical analysis for nitrotyrosine and poly(ADP-ribose) synthetase (PARS) revealed positive staining in the inflamed joints of CII-treated rats. The degree of nitrotyrosine and PARS staining was markedly reduced in tissue sections obtained from CII-treated rats that had received tempol. Furthermore, radiographs revealed protection against bone resorption and osteophyte formation in the joints of tempol-treated rats. CONCLUSION: This study is the first to provide evidence that tempol, a small molecule that permeates biologic membranes and scavenges reactive oxygen species, attenuates the degree of chronic inflammation and tissue damage associated with CIA in the rat.

Calpain inhibitor I reduces the development of acute and chronic inflammation.

There is limited evidence that inhibition of the activity of the protease calpain I reduces inflammation. Here we investigate the effects of calpain inhibitor I in animal models of acute and chronic inflammation (carrageenan-induced pleurisy and collagen-induced arthritis). We report here for the first time that calpain inhibitor I (given at 5, 10, or 20 mg/kg i.p. in the pleurisy model or at 5 mg/kg i.p every 48 hours in the arthritis model) exerts potent anti-inflammatory effects (eg, inhibition of pleural exudate formation, mononuclear cell infiltration, delayed the development of the clinical signs and histological injury) in vivo. Furthermore, calpain inhibitor I reduced (1) the staining for nitrotyrosine and poly (ADP-ribose) polymerase (immunohistochemistry) and (2) the expression of inducible nitric oxide synthase and cyclooxygenase-2 in the lungs of carrageenan-treated rats and in joints from collagen-treated rats. Thus, prevention of the activation of calpain I reduces the development of acute and chronic inflammation. Inhibition of calpain I activity may represent a novel therapeutic approach for the therapy of inflammation.

The tyrosine kinase inhibitor tyrphostin AG126 reduces the development of acute and chronic inflammation.

Protein tyrosine kinases help to regulate the expression of many genes that play important roles in inflammation. Here we investigate the effects of the tyrosine kinase inhibitor tyrphostin AG126 in two animal models of acute and chronic inflammation, carrageenan-induced pleurisy and collagen-induced arthritis. We report here that tyrphostin AG126 (given at 1, 3, or 10 mg/kg i.p. in the pleurisy model or 5 mg/kg i.p. every 48 hours in the arthritis model) exerts potent anti-inflammatory effects in animal models of acute and chronic inflammation in vivo. These include the inhibition of pleural exudate formation and mononuclear cell infiltration (pleurisy model) and the development of clinical signs and tissue injury (arthritis model). Furthermore, tyrphostin AG126 reduced the staining for nitrotyrosine and poly (ADP-ribose) polymerase (by immunohistochemistry) and the expression of inducible nitric oxide synthase and cyclooxygenase-2 in the lungs of carrageenan-treated rats and in the joints from collagen-treated rats. Thus, we provide the first evidence that prevention of the activation of protein tyrosine kinases reduces the development of acute and chronic inflammation, and that inhibition of the activity of certain tyrosine kinases may represent a novel approach for the therapy of inflammation.