bluuebunny/crossref_metadata_2025 huggingface dataset:
Specific In Situ Hybridization of Haemobartonella felis with a DNA Probe and Tyramide Signal Amplification
Authors: Berent L. M. , Messick J. B. , Cooper S. K. , Cusick P. K.
Published: April 2003

Haemobartonella felis is an epierythrocytic bacterium suspected to be the causative agent of feline infectious anemia. Previous studies with a polymerase chain reaction assay have identified a mycoplasmal 16S rRNA gene sequence that coincides with clinical disease and the presence of organisms in the blood. Tissues from a cat experimentally infected with H. felis were used for in situ hybridization studies to physically link this 16S rRNA gene to the organisms on the red cells. A biotin-labeled probe was used in conjunction with tyramide signal amplification to visualize the hybridization signal. This study clearly demonstrates a specific hybridization signal on the red cells in the tissues of the H. felis-infected cat. This in situ hybridization study is the final step in fulfilling the molecular guidelines for disease causation and proves that H. felis, a mycoplasmal organism, is the causative agent of feline infectious anemia.
Mammalian Microsporidiosis
Authors: Wasson K. , Peper R. L.
Published: April 2003

The phylum Microspora contains a diverse group of single-celled, obligate intracellular protozoa sharing a unique organelle, the polar filament, and parasitizing a wide variety of invertebrate and vertebrate animals, including insects, fish, birds, and mammals. Encephalitozoon cuniculi is the classic microsporidial parasite of mammals, and encephalitozoonosis in rabbits and rodents has been and continues to be recognized as a confounding variable in animal-based biomedical research. Although contemporary research colonies are screened for infection with this parasite, E. cuniculi remains a cause of morbidity and mortality in pet and conventionally raised rabbits. In addition, E. cuniculi is a potential pathogen of immature domestic dogs and farm-raised foxes. The recent discovery and identification of Encephalitozoon intestinalis, Encephalitozoon hellem, and Enterocytozoon bieneusi, in addition to E. cuniculi, as opportunistic pathogens of humans have renewed interest in the Microspora. Veterinary pathologists, trained in the comparative anatomy of multiple animal species and infectious disease processes, are in a unique position to contribute to the diagnosis and knowledge of the pathogenesis of these parasitic diseases. This review article covers the life cycle, ultrastructure, and biology of mammalian microsporaidia and the clinical disease and lesions seen in laboratory and domestic animals, particularly as they relate to Encephalitozoon species. Human microsporidial disease and animal models of human infection are also addressed. Often thought of as rabbit pathogens of historical importance, E. cuniculi and the related mammalian microsporidia are emerging as significant opportunistic pathogens of immunocompromised individuals.
Skeletal Lesions of Canine Hepatozoonosis Caused by Hepatozoon americanum
Authors: Panciera R. J. , Mathew J. S. , Ewing S. A. , Cummings C. A. , Drost W. T. , Kocan A. A.
Published: April 2003

Canine hepatozoonosis, caused by Hepatozoon americanum, is an emerging tick-borne disease of dogs in North America. In addition to the skeletal and cardiac myositis that are prominent features of the disease, there is disseminated periosteal bone proliferation in most dogs that manifest clinical disease. Each of six experimentally infected animals (four dogs and two coyotes) and seven of eight naturally infected dogs had gross or histopathologic osteoproliferative lesions. Experimental animals were 6–9 months of age when exposed. Naturally infected dogs were 8 months to 11 years old when subjected to necropsy. Lesions occurred primarily on the diaphysis of the more proximal long bones of the limbs; however, flat and irregular bones were frequently involved. Lesions involving metacarpals, metatarsals, and digits were infrequent. The earliest observed periosteal lesions were in an experimentally infected dog 32 days after exposure to sporulated oocysts of H. americanum. There were hypertrophy and hyperplasia of osteoprogenitor cells, and osteoblasts appeared in the cellular zone of the periosteum. Spicules of woven bone oriented perpendicularly to bone cortex followed. Later yet, periosteal new bone was remodeled and tended to become oriented parallel to the cortical bone. Horizontally oriented zones of remodeled, condensed bone sometimes occurred in multiple layers on the original cortex, forming “pseudocortices.” The osseous lesions of American canine hepatozoonosis, with few variations, are remarkably similar to those of hypertrophic osteopathy in domestic dogs and other mammalian species, including humans.
Anophthalmia and Retinal Degeneration Associated with Stenosis of the Optic Foramen in Fischer 344 Rats
Authors: Shibuya K. , Tajima M. , Nunoya T.
Published: April 2003

Bilateral anophthalmia was discovered in a male rat (No. 1) and unilateral anophthalmia was found in the left eye of two female rats (Nos. 2 and 3) derived from a Fischer 344 inbred colony. One male rat (No. 4), a littermate of No. 3, had externally normal eyes, but his left eye had severe retinal atrophy, which was detected by ophthalmoscopy. The eyelids in both eyes of No. 1 and in the left eyes of Nos. 2 and 3 were present. Radiography of the skull revealed small optic foramina on both sides of No. 1 and on the affected side of Nos. 2, 3, and 4. Histologically, both globes and optic nerves (ONs) of No. 1 and the left globe and ONs of Nos. 2 and 3 were completely missing. Diffuse retinal degeneration in the left globe and axonal degeneration in the left ON and the right optic tract were observed in No. 4. Dysplasia of the sphenoid bone associated with stenosis of the optic foramen was detected on the affected side of all rats. Thus, ON aplasia in anophthalmic rats and atrophic ON in a rat with retinal degeneration seem to be closely related to stenosis of the optic foramen.
Canine Large Granular Lymphocyte Leukemia and its Derived Cell Line Produce Infectious Retroviral Particles
Authors: Ghernati I. , Corbin A. , Chabanne L. , Auger C. , Magnol J. P. , Fournel C. , Monier J. C. , Darlix J. L. , Rigal D.
Published: April 2003

We describe a case of large granular lymphocyte (LGL) leukemia in a dog that we followed over a period of 2 years. Analysis of a hematological profile revealed lymphocytosis (19,500 lymphocytes per microliter; reference values, 1,000–4,800 lymphocytes per microliter), with a majority of LGL on the blood smear. LGL is defined as a lymphoid subset comprising 10% of peripheral blood mononuclear cells and corresponding to either CD3- CD8- NK cells or CD3+ CD8+ T cells. The cells are characterized by abundant basophilic cytoplasm containing distinct granules of variable size and number. The characteristic phenotype of our leukemic LGL is of a cytotoxic T cell, CD3+ and CD8+. A new cell line, DLC 02, was established from the peripheral lymphocytes of the leukemic dog. Particles with type C retroviral morphology were found in ultrathin sections of DLC 02 cell pellets. These particles were found to have a sucrose gradient density of 1.17 g/liter and a reverse transcriptase activity with an Mn21 preference, suggesting that they correspond to a mammalian type C oncovirus.
Calcium Hydroxylapatite Deposition Disease in a Great Dane Puppy
Authors: Wünschmann A. , Marshall B. , Mitchell J. , Weisbrode S.
Published: April 2003

A 10-week-old male Great Dane Puppy was presented for sudden onset tetraataxia and severe paresis of the front legs. Mineral deposits were detected radiographically, at gross postmortem examination, and light microscopically between the vertebral arches of multiple cervical and lumbar vertebrae. These deposits were associated with the interarchial ligaments (ligamentia interarcualia), along the interfaces of the synovium and articular cartilage of multiple cervical, thoracic, and lumbar facets, on the dorsal aspect of several thoracic intervertebral discs, and at the insertion of muscles at the lateral aspect of several cervical and thoracic vertebral bodies. The mineral deposits were associated with a granulomatous inflammation and synovial fibrocartilaginous metaplasia and proliferation, which was focally exuberant. X-ray diffraction analyses of the mineral deposits revealed calcium hydroxylapatite as the major component. The clinical signs in this puppy were due to focal compression of the spinal cord by marked extraarticular ligament-associated fibrocartilaginous proliferation.
The Pathology of Spontaneous Paratuberculosis in the North American Bison (Bison bison)
Authors: Buergelt C. D. , Layton A. W. , Ginn P. E. , Taylor M. , King J. M. , Habecker P. L. , Mauldin E. , Whitlock R. , Rossiter C. , Collins M. T.
Published: April 2003

Gross and histopathologic examinations were performed on 70 North American bison ( Bison bison) from a Mycobacterium avium paratuberculosis culture-positive herd. The bison examined were part of a breeding herd totaling 2,800 animals. Eight of 70 (11%) animals had gross findings of intestinal mucosal thickening, and 16 of 70 (23%) of the animals had enlarged mesenteric lymph nodes. Histologic lesions compatible with Johne's disease were diagnosed in 30 of 70 (43%) bison on the basis of the demonstration of noncaseating granulomatous inflammatory infiltrates and of one or more acid-fast bacilli characteristic of Mycobacterium avium paratuberculosis. A suspicious diagnosis of Johne's disease was obtained in 11 of 70 (16%) bison on the basis of the observation of noncaseating granulomatous inflammatory infiltrates without demonstrable acid-fast bacteria. Twenty-nine of 70 (41%) animals were assessed as histologically paratuberculosis free. Histologic results were compared to Johne's disease tests such as culture, serology, and polymerase chain reaction, which were performed on some of the cohort animals.
Endocardial Ossifying Myxoma of the Right Atrium in a Cat
Authors: Campbell M. D. , Gelberg H. B.
Published: April 2003

Primary cardiac neoplasms are rare in humans and animals. In humans, the most common primary cardiac tumor is the myxoma, which is frequently found in the left atrium. Cardiac myxoma has been reported in the dog but not in the cat. We describe the gross, immunohistochemical, and light microscopic examination of a myxoma in the right atrium of a 6-year-old domestic shorthair cat. Histologically, the tumor consisted predominantly of mesenchymal cells with several foci of bone and cartilage present. The tumor was encapsulated and benign.
Meningeal Osteosarcoma in a Dog
Authors: Ringenberg M. A. , Neitzel L. E. , Zachary J. F.
Published: April 2003

A meningeal osteosarcoma was diagnosed in a dog displaying neurologic signs compatible with a space-occupying cerebellar lesion. Gross lesions, restricted to the brain, consisted of a solitary, compressive mass attached to the dura mater overlying the left cerebellum. The mass was composed of single and multinucleated, atypical polygonal cells that lined or rested within lacuna surrounded by eosinophilic, mineralized matrix. The matrical component stained dark green-yellow to blue with Movat's pentachrome stain, deep blue to red with Heidenhain aniline blue stain, and brown-black with Von Kossa stain. Results of these stains were interpreted as tumor osteoid. Foci of dural mineralization and osseous metaplasia were present at the point of tumor attachment. The microscopic observations were interpreted as an osteosarcoma of extraskeletal origin. To our knowledge, these findings represent the first documented case of a meningeal osteosarcoma in a domestic animal species.
Primary Pulmonary Artery Leiomyosarcoma in an Adult Dog
Authors: Callanan J. J. , McCarthy G. M. , McAllister H.
Published: April 2003

A 7-year-old neutered female English Setter presented with syncope, anemia, and weight loss. Clinical examination revealed a systolic murmur and echocardiography demonstrated a mass on the pulmonic valve. Postmortem examination confirmed the presence of a pulmonic valve mass that extended along the pulmonary trunk and into the left pulmonary artery. Multiple pale nodules were observed in the right lung. Microscopic examinations of the pulmonary artery mass and the lung nodules revealed a pleomorphic population of spindle cells often arranged in broad bands containing strap-like nuclei and eosinophilic cytoplasm devoid of cross striations. The neoplastic cells expressed vimentin and alpha-smooth muscle actin but did not express desmin, CD31, factor VIII, or S100. The presentation, histological features, immunocytochemical profiles, and behavior of this tumor were indicative of a primary pulmonary artery leiomyosarcoma with lung metastasis.
Cholesterol Granulomas in Three Meerkats (Suricata suricatta)
Authors: Sladky K. K. , Dalldorf F. G. , Steinberg H. , Wright J. F. , Loomis M. R.
Published: April 2003

Cholesterol granulomas are uncommon pathologic lesions in animals, although they are important intracranial tumors in humans. This report describes cholesterol granulomas associated with multiple organ systems of three captive meerkats. In the most severe case, meerkat No. 1, the pathologic behavior of the cholesterol granuloma was unique in that it appeared to locally invade the cerebrum and calvarium, possibly contributing to neurological deficits observed antemortem. A review of other meerkat necropsies revealed incidental, asymptomatic cholesterol granulomas in organs of two other individuals, meerkat Nos. 2 and 3. Histologically, all lesions were composed of cholesterol clefts admixed with large, foamy macrophages containing hemosiderin, multinucleated giant cells, lymphocytes, plasma cells, and foci of mineralization. Hypercholesterolemia was documented in two of the three meerkats.
Activation of the Immune System is the Pivotal Event in the Production of Wasting Disease in Pigs Infected with Porcine Circovirus-2 (PCV-2)
Authors: Krakowka S. , Ellis J. A. , McNeilly F. , Ringler S. , Rings D. M. , Allan G.
Published: April 2003

Porcine circovirus (PCV)-2, a newly described single-stranded circular DNA virus pathogen of swine is the cause of postweaning multisystemic wasting syndrome (PMWS). In gnotobiotic piglets, PCV-2 infection alone produces asymptomatic infection without evidence of overt PMWS. Gnotobiotic piglets infected with PCV-2 were injected with keyhole limpet hemocyanin in incomplete Freund's adjuvant (KLH/ICFA), and the effects on virus production and development of PMWS were determined. In the first experiment, piglets were injected subcutaneously on the left hip and shoulder, and viral burden was assessed in regional lymph nodes draining the injection sites and in contralateral lymph nodes 13–14 days after infection. Immune activation increased the number of virus antigen-positive cells in draining lymph nodes and increased the amount of infectious virus recovered by 1–4 log10. In a second experiment, the effects of injections of KLH/ICFA with or without concurrent stimulation of peritoneal macrophages by intraperitoneal injections of thioglycollate broth on induction of PMWS was assessed. All immunized piglets developed moderate to severe PMWS, whereas none of the piglets infected with PCV-2 alone developed PMWS. In PMWS-affected piglets, extensive replication of PCV-2 was documented by both immunocytochemistry and quantitative viral titrations. Thus, immune activation is a key component of the pathogenesis of PCV-2-associated PMWS in swine.
Uptake of Mycobacterium avium subsp. paratuberculosis through the Distal Small Intestinal Mucosa in Goats: An Ultrastructural Study
Authors: Sigurðardóttir Ó. G. , Press C. M. , Evensen Ø.
Published: April 2003

Various pathogens gain access to the intestinal wall via specialized cells, the M cells, found among the follicle-associated epithelial cells overlying the domes of the Peyer's patches. The present study was undertaken to examine the uptake of live Mycobacterium avium subsp. paratuberculosis in the distal small intestine of goat kids. Following laparotomy, distal small intestinal segments of five goats were ligated and injected with bacterial suspension. After 1 hour, the intestinal segments were excised and fixed for light and electron microscopic studies. M. a. paratuberculosis organisms were observed by transmission electron microscopy at locations in the intestinal wall, suggesting transcellular transportation through the M cells. The organisms were present both in the cytoplasm of the M cells and in the cytoplasm of intraepithelial leukocytes found in M-cell pockets. Intercellular bacteria between M cells were occasionally seen. Bacteria were not observed in association with the absorptive epithelium. This study indicates that in goat kids, M. a. paratuberculosis enters the intestinal wall primarily through the M cells in the follicle-associated epithelium of the Peyer's patches.
Gastrointestinal Stromal Tumors of the Equine Cecum
Authors: Hafner S. , Harmon B. G. , King T.
Published: April 2003

Ten cecal tumors were identified during the postmortem examination of seven horse carcasses at slaughter (one horse had three tumors). The multinodular and hemorrhagic tumors ranged from 1 to 10 cm in diameter and consisted of spindle cells arranged in thin, interconnected trabeculae that were often separated by sinuses filled with mucinous fluid, erythrocytes, and siderophages. Spindle cells of all tumors were immuno-positive for vimentin, neuron-specific enolase, and c-kit protein but lacked reactivity with antibodies to glial fibrillary acidic protein, S100 protein, and desmin. In one tumor, spindle cells diffusely bound antibodies to synaptophysin. Most tumors contained focal reactivity to smooth muscle actin antibodies; one tumor reacted diffusely. Ultrastructurally, tumor cells were connected by desmosome-like structures and exhibited extended cell processes; some contained dense core neurosecretory granules. These equine stromal tumors appeared to share some characteristics with human gastrointestinal stromal tumors.
Proliferative Vasculopathy and Cutaneous Hemorrhages in Porcine Neonates Infected with the Porcine Reproductive and Respiratory Syndrome Virus
Authors: Scruggs D. W. , Sorden S. D.
Published: April 2003

Severe cutaneous hemorrhages with dermal and subcutaneous capillary angioplasia were seen in aborted and stillborn piglets, concurrently with an acute outbreak of porcine reproductive and respiratory syndrome virus (PRRSV) abortions. Histologically, the lesions consisted of angioblastic endothelial cells and immature capillary vascular structures coursing through the edematous myxomatous dermis and subcutis. Proliferating capillaries often were surrounded by large and foamy macrophages that stained positively for PRRSV by immunohistochemistry. The sudden appearance of these vascular lesions during the PRRSV outbreak and their abrupt disappearance after the abortion storm, along with the immunohistochemical localization of PRRSV-positive macrophages adjacent to the proliferating capillaries, suggest that PRRSV likely played a role in the development of these unusual lesions.
Detection and Localization of ApxI, -II, and -III Genes of Actinobacillus pleuropneumoniae in Natural Porcine Pleuropneumonia by In Situ Hybridization
Authors: Choi C. , Kwon D. , Min K. , Chae C.
Published: April 2003

In situ hybridization techniques that employed a nonradioactive digoxigenin-labeled probe were used to detect and localize ApxI, II and III genes in tissue sections of pneumonic lung naturally infected with Actinobacillus pleuropneumoniae. In pigs infected with either serotype 2 or 6, a hybridization signal for apxIICA, apxIIICA, apxIBD, and apxIIIBD was detected, and in pigs infected with serotype 5, a hybridization signal for apxICA, apxIICA, and apxIBD was detected in the pneumonic lesions. A hybridization signal for apxIICA and apxIBD was detected in pigs infected with serotype 7. A strong hybridization signal for apx genes was seen in streaming degenerate alveolar leukocytes bordering zones of coagulative necrosis. Simultaneous detection of hybridization signals for the apxCA and apxBD genes provided scientific evidence that the expression of the apx genes could be potential indicators of the production of corresponding Apx toxins. This study demonstrates the expression of ApxI, II, and III genes in pneumonic lesions caused by A. pleuropneumoniae.
Disseminated Mycobacterium celatum (Type 3) Infection in a Domestic Ferret (Mustela putorius furo)
Authors: Valheim M. , Djønne B. , Heiene R. , Caugant D. A.
Published: April 2003

A 4-year-old male ferret ( Mustela putorius furo) had a 6-month history of weight loss and gradual development of depression and coughing. Necropsy findings included pale gray tissue around the distal trachea, multiple nodules in the lungs, a single nodule in the stomach wall, gray foci in the liver, and enlarged lymph nodes. Histologic examination revealed multifocal to coalescing granulomatous inflammation in the trachea, lungs, stomach, liver, and lymph nodes, with acid-fast bacteria in epithelioid cells and macrophages. The acidfast bacteria were identified as Mycobacterium celatum (type 3) using DNA sequence analysis of the 16S ribosomal DNA gene. M. celatum is a recently described mycobacterium isolated mainly from immunocompromised humans. This is the first report of M. celatum infection in an animal.
Point Mutation of neu Oncogene in Animal Peripheral Nerve Sheath Tumors
Authors: Stoica G. , Tasca S. I. , Kim H.-T.
Published: April 2003

Thirty-four peripheral nerve sheath tumors of four domesticated animal species were characterized and assayed for point mutation of the neu oncogene. Based on their morphoimmunophenotype, 32 tumors were classified as schwannomas. Schwannoma morphology was characterized by the presence of Antoni type A and B pattern and immunoreactivity for S-100 protein and vimentin. Two anaplastic and metastatic tumors originating from spinal cord root, immunonegative for S-100 protein and positive for vimentin, were classified as malignant peripheral nerve sheath tumors (MPNSTs). Four malignant schwannomas and two MPNSTs expressed a point mutation of the neu oncogene by the polymerase chain reaction-restriction fragment length polymorphism method. The finding of neu oncogene mutation could be a useful diagnostic genetic marker in the malignant form of peripheral nerve sheath tumors in animals.
Reduced Expression of Cyclin-dependent Kinase Inhibitor p27Kip1 in Feline Lymphoma
Authors: Madewell B. , Griffey S. , Walls J. , Gandour-Edwards R.
Published: April 2003

Expression of p27Kip1 was identified in feline lymphoid tissues by immunohistochemistry. In normal lymphoid tissues, p27Kip1 was detected as a distinct nuclear stain in lymphocytes of the follicular mantle zone and interfollicular small lymphocytes, whereas activated lymphoblasts in the germinal center were negative. Lymphoid hyperplasia was similarly immunolabeled but with an expanded mantle zone and marginal zone of p27Kip1-reactive lymphocytes. Both T- and B-cell lymphomas lacked p27Kip1 immunolabel and were determined to be proliferative based on immunohistochemical detection of the Ki-67 antigen. Scattered p27Kip1- immunolabeled lymphocytes were detected throughout the lamina propria of most specimens characterized as lymphoplasmacytic enteritis. The results of this study suggest that the antiproliferative effect of the cell cycle regulator p27Kip1 is abrogated in feline lymphoma, presumably allowing cells to bypass the G1-S checkpoint of the cell cycle.
Teratoma in a Feline Unilateral Cryptorchid Testis
Authors: Miyoshi N. , Yasuda N. , Kamimura Y. , Shinozaki M. , Shimizu T.
Published: April 2003

A 14- × 12- × 6-cm (approximately 600 g) cryptorchid testis was surgically removed with the omentum from the posterior portion of the abdominal cavity of a 2-year-old male American Shorthair cat. At the time of a previous orchiectomy, a unilateral testis had been discovered in the scrotum. The cut surface of the cryptorchid testis consisted of solid areas with many cysts containing fluid and spongy soft areas. Histologically, the cryptorchid testis was composed of neuroectodermal components and diffuse immature glial tissues, cystic, tubular, and papillary epithelial tissues, and immature cartilaginous tissues. A metastatic mass in the omentum had histologic structures similar to those of the cryptorchid testis. The present case was diagnosed as teratoma in a feline unilateral cryptorchid testis.
Melan A and S100 Protein Immunohistochemistry in Feline Melanomas: 48 Cases
Authors: Ramos-Vara J. A. , Miller M. A. , Johnson G. C. , Turnquist S. E. , Kreeger J. M. , Watson G. L.
Published: April 2003

Immunohistochemistry, using a monoclonal antibody to Melan A and a polyclonal antibody to S100 protein, was applied to 48 formalin-fixed, paraffin-embedded specimens of feline melanoma. Forty-two cutaneous, three oral, one mucocutaneous, and two metastatic melanomas comprised the tumors. Thirty-two tumors (67%) were positive for Melan A and 42 (87.5%) were positive for S100. All but one of the tumors that were positive for Melan A were also positive for S100. S100 was detected in 11 of 16 tumors that were negative for Melan A. Seventy-five percent (9 of 12) of amelanotic melanomas were negative for Melan A. Normal adrenal cortex, the cerebellum, and the skin had cells that were positive for Melan A. Sebaceous adenoma was the only nonmelanocytic tumor examined that reacted with antibody to Melan A. Although less sensitive than S100 protein, Melan A is more specific for melanoma and is useful in differentiating feline cutaneous melanoma from the more common pigmented basal cell tumor.
Localized and Disseminated Histiocytic Sarcoma of Dendritic Cell Origin in Dogs
Authors: Affolter V. K. , Moore P. F.
Published: April 2003

Canine histiocytic proliferative disorders include a wide spectrum of diseases characterized by different biologic behaviors. The etiology and pathogenesis of these diseases are largely unknown. The clinicopathologic, morphologic and immunophenotypic characteristics of canine localized and disseminated histiocytic sarcoma were examined in 39 dogs. Rottweilers, Bernese Mountain Dogs, and retrievers were most commonly affected (79%). Localized histiocytic sarcomas (19 dogs) arose from a single site, and metastatic lesions were observed in draining lymph nodes. Predilection sites were subcutis and underlying tissues on extremities, but tumors occurred in other locations, including spleen, lung, brain, nasal cavity, and bone marrow. Disseminated histiocytic sarcomas (20 dogs), a multisystem disease previously described as malignant histiocytosis, primarily affected spleen, lungs, bone marrow, liver, and lymph nodes. Both localized and disseminated canine histiocytic sarcomas were composed of pleomorphic tumor cell populations. CD1+, CD4-, CD11c+, CD11d-, MHC II+, ICAM-1+, Thy-1± tumor cells were identified in all snap-frozen samples (31 dogs). This phenotype is characteristic for myeloid dendritic antigen-presenting cell lineage. Hence, canine localized and disseminated histiocytic sarcomas are likely myeloid dendritic cell sarcomas. Dendritic antigen-presenting cells are a heterogeneous cell population with regards to their ontogeny, phenotype, function, and localization. The exact sublineage of the proliferating dendritic antigen-presenting cells involved in canine histiocytic sarcomas remains to be determined. Phenotypic analysis of formalin-fixed tissues from eight dogs was limited by available markers. Morphologic features and the phenotype CD18+, CD3-, and CD79a- were the most useful criteria to indicate likely histiocytic origin.
Mixed Apocrine Sweat Gland Tumor of the Tail in a Cow
Authors: Gulbahar M. Y. , Alkan I. , Aslan L. , Golen I.
Published: April 2003

A 4-year-old native-breed cow had a mass with wide areas of ulceration and hemorrhage at the base of the tail at the same level as the vulva. The tumor was 19 X 13 X 11 cm, appeared red-brown, and was firm to hard, with gritty areas apparent on cut surface. Histologically, the tumor mass was composed of multilayered epithelial cells forming glandular structures with occasional apical blebs and rare solidly packed cells in nests. The stroma included fibrous connective tissue, scattered or periglandular sheets of spindle-shaped cells resembling myoepithelium, several cartilaginous formations, and numerous irregular islands of mineralized osteoid, well-formed bone trabeculae lined by osteoblasts, and many osteoclast-like multinucleated giant cells among or near the neoplastic epithelium. Immunohistochemically, the neoplastic epithelium was positive for pan-cytokeratin (AE1/AE2) and cytokeratin 19 but was negative for cytokeratin 18. Spindle-shaped cells were stained with alpha smooth muscle actin (αSMA) and to a lesser extent vimentin antibodies. The cells of osteogenic lineage and spindle cells closely associated with the osteoid showed strong immunostaining for vimentin but not for αSMA. Immunostaining for neuron-specific enolase and S100 protein was not observed in any component of the tumor mass. These findings suggested that the origin of bone formation was undifferentiated mesenchymal cells with osteogenic potential.
Immunohistochemical Staining Patterns of Canine Meningiomas and Correlation with Published Immunophenotypes
Authors: Barnhart K. F. , Wojcieszyn J. , Storts R. W.
Published: April 2003

This study examined immunohistochemical staining patterns for several meningioma variants involving either the brain or spinal cord of dogs. Formalin-fixed, paraffin-embedded tissue from 15 tumors was obtained. The selected tumor group included seven meningothelial, three transitional, two malignant (anaplastic), one myxoid, one papillary, and one osteomatous meningiomas. Tumors were evaluated for reactivity to the following six immunohistochemical markers: vimentin, pancytokeratin, glial fibrillary acidic protein (GFAP), S100, neuron-specific enolase (NSE), and synaptophysin. Vimentin expression was detected in all meningiomas, and 14 of 15 tumors demonstrated intense vimentin staining in more than 50% of the neoplastic cells. Pancytokeratin expression was present in 11 of 15 neoplasms; however, positive staining frequently was focal and often involved a small percentage of the neoplastic cells. GFAP expression was detected in a single, anaplastic meningioma. Although expression of NSE and S100 was detected in 12 of 25 meningiomas, the intensity of the staining and the percentage of positive neoplastic cells was highly variable. Synaptophysin was uniformly negative. These results will help to establish immunohistochemical profiles for meningiomas that will improve our ability to correctly differentiate these neoplasms of meningeal origin from central nervous system tumors originating from other sites.
Participation of Different Macrophage Populations and Myofibroblastic Cells in Chronically Developed Renal Interstitial Fibrosis after Cisplatin-induced Renal Injury in Rats
Authors: Yamate J. , Sato K. , Ide M. , Nakanishi M. , Kuwamura M. , Sakuma S. , Nakatsuji S.
Published: April 2003

To shed some light on the mechanisms behind renal fibrogenesis, the present study immunohistochemically investigated the participation of different macrophage populations and myofibroblastic cells in rat renal interstitial fibrosis developed chronically after repeated injection of cisplatin (2 mg/kg body weight, once weekly for 7 weeks). During the 19-week recovery period after the final injection, fibrotic lesions progressively developed in the corticomedullary junction, with the greatest level at post-final injection (FPI) week 5, and then the lesions were gradually repaired by PFI week 19, indicative of a healing process. In conformity with the development of fibrotic lesions, the number of myofibroblastic cells reacting with an anti-α-smooth muscle actin antibody was increased, with a peak at PFI week 3, and collagens (types I, III, and IV), fibronection, and laminin were excessively accumulated in these areas. Interstitial cells forming the fibrotic lesions showed mitotic activity at the early stages, whereas they disappeared by apoptosis in the healing process. A large number of cells reacting with an antibody of ED1 (for exudate macrophages), ED2 (for resident macrophages), or OX6 (for major histocompatibility complex class II-presenting macrophages and interstitial dendritic cells) had already appeared at PF1 week 1, and then their numbers increased, with a peak at PFI weeks 7, 3, and 9 in ED1-, ED2-, and OX6-positive cells, respectively. Thereafter, the number of ED1- and ED2-positive cells decreased, whereas the number of OX6-positive cells persisted at a high level until PFI week 19. In the healing process, clusters of lymphocytes were present, the development of which might have been related to OX6-positive cells. The present study demonstrated that chronically developing rat renal interstitial fibrosis might be produced by the complicated mechanisms evoked by interactions between different macrophage populations and myofibroblastic cells, because macrophages show heterogeneous functions depending on microenvironmental factors.
Pathogenesis of Six Pigeon-Origin Isolates of Newcastle Disease Virus for Domestic Chickens
Authors: Kommers G. D. , King D. J. , Seal B. S. , Carmichael K. P. , Brown C. C.
Published: April 2003

The pathogenesis of six pigeon-origin isolates of Newcastle disease virus (NDV) was investigated in chickens. Four isolates were previously defined as the variant pigeon paramyxovirus 1 (PPMV-1), and two isolates were classified as avian paramyxovirus 1 (APMV-1). Birds inoculated with PPMV-1 isolates were euthanatized, and tissue samples were collected at 2, 5, and 10 days postinoculation (DPI). Birds inoculated with APMV-1 isolates died or were euthanatized, and tissue samples were collected at 2, 4, and 5 DPI. Tissues were examined by histopathology, immunohistochemistry (IHC) for the presence of NDV nucleoprotein, and in situ hybridization (ISH) for the presence of viral mRNA for the matrix gene. Spleen sections were stained by the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay and by IHC using an anti-active caspase-3 antibody (IHC-Casp) to detect apoptotic cells. Brain sections of PPMV-1-infected birds were examined by IHC to detect T and B lymphocytes and glial fibrillary acidic protein (GFAP). Histologically, birds inoculated with PPMV-1 isolates had marked lesions in the heart and brain. Presence of viral nucleoprotein and viral mRNA in the affected tissues was confirmed by IHC and ISH, respectively. Numerous reactive astrocytes were observed in brain sections stained for GFAP. Among all the isolates, the IHC-Casp demonstrated that apoptosis was very prominent in the ellipsoid-associated cells of the spleen at 2 DPI. Results of the TUNEL assay indicated that apoptotic cells were prominent at 5 DPI and were more randomly distributed. The clinical signs and gross and histopathologic changes observed in the APMV-1-infected birds were characteristic of an extensive infection with highly virulent NDV evident by IHC.
Chronologic Localization of Mycoplasma hyopneumoniae in Experimentally Infected Pigs
Authors: Kwon D. , Choi C. , Chae C.
Published: April 2003

The chronologic localization of Mycoplasma hyopneumoniae was examined by in situ hybridization in experimentally infected pigs for a period of 35 days after intratracheal inoculation. M. hyopneumoniae DNA was detected in bronchial and bronchiolar epithelial cells from infected pigs at 7, 14, 21, and 28 days postinoculation (DPI) and in alveolar and interstitial macrophages and type I pneumocytes from infected pigs at 14, 21, 28, and 35 DPI. Strong hybridization signals for M. hyopneumoniae were detected mainly at the luminal surface of bronchial and bronchiolar lining epithelial cells. When a hybridization signal was detected at the luminal surface of bronchial and bronchiolar lining epithelial cells, a given bronchus or bronchiole also exhibited peribronchiolar lymphoid cuffing. These observations suggested that the presence of M. hyopneumoniae in different tissues could be due to a difference in the duration of the infection.
Localization of Astrovirus in Experimentally Infected Turkeys as Determined by In Situ Hybridization
Authors: Behling-Kelly E. , Schultz-Cherry S. , Koci M. , Kelley L. , Larsen D. , Brown C.
Published: April 2003

Twenty-one 3-day-old turkey poults from British United Turkeys of America were orally inoculated with a recently characterized astrovirus, TAstV-2, isolated from turkeys with poult enteritis and mortality syndrome. At 1, 2, 3, 4, 5, 7, and 9 days postinfection (dpi), three inoculated birds were euthanatized, and tissues (intestines, spleen, bursa, and thymus) were collected immediately into 10% neutral buffered formalin. Inoculated birds were diarrheic by 3 dpi, and frothy feces persisted throughout the experimental period. Histologically, there was only slight evidence of enteric damage, which was characterized by mild epithelial necrosis, lamina propria infiltrates, minimal villus atrophy, and mild crypt hyperplasia. In situ hybridization, using a negative sense digoxigenin-labeled riboprobe to the capsid gene of TAstV-2, revealed viral RNA in intestinal epithelial cells at the basal margins of the villi, in distal small intestine, and in cecum at 2 dpi, with subsequent extension to epithelium of the large intestine and proximal small intestine (3–5 dpi). Minimal virus remained by 9 dpi.
B-Cell Leukemia in a Sheep
Authors: Valentine B. A. , Mcdonough S. P.
Published: April 2003

Necropsy examination was performed on an 8.5-year-old Finnish ewe euthanatized because of progressive respiratory distress, cachexia, and weakness. Significant postmortem findings included a diffusely enlarged, dark-red friable liver, mild splenomegaly, and mild mesenteric lymphadenopathy. Examination of multiple tissue sections revealed intravascular atypical mononuclear cells in all tissues examined, with a leukemic pattern of infiltration of mesenteric lymph nodes, liver, lung, and spleen. Neoplastic cells were positive for CD79a and negative for CD-3, BLA.36, and CD68 leukocytic markers. The final diagnosis was B-cell leukemia.
Intramedullary Hemangioblastoma in a Dog
Authors: Cantile C. , Baroni M. , Tartarelli C. L. , Campani D. , Salvadori C. , Arispici M.
Published: April 2003

A 6-year-old male Pointer dog was presented with a 4-week history of progressive hind-limb stiffness. Magnetic resonance imaging demonstrated a focal intramedullary lesion at T1 level with a pattern of ring contrast enhancement. At necropsy, a circumscribed intramedullary reddish-gray tumor was observed. Microscopically, the tumor was composed of thin-walled capillaries lined by endothelial cells and separated by pleomorphic cells (stromal cells) with a moderate degree of anisokaryosis. Immunohistochemically, the endothelial cells were positive for factor VIII–related antigen and the stromal cells were positive for neuron-specific enolase and vimentin. GFAP-positive astrocytes were occasionally observed within the tumor. Both endothelial and stromal cells were negative for synaptophysin, S-100 protein, pankeratin, smooth muscle actin, CD34, CD68, α1-antichymotrypsin, and lysozyme. The tumor showed considerable morphologic and immunohistochemical similarities with human hemangioblastoma, and hence the inclusion of this tumor type within the primary neoplasms of the canine central nervous system is suggested.
Histology of Uterine Leiomyoma and Occurrence in Relation to Reproductive Activity in the Baltic Gray Seal (Halichoerus grypus)
Authors: Bäcklin B.-M. , Eriksson L. , Olovsson M.
Published: April 2003

A high prevalence of uterine leiomyoma has been reported in Baltic gray seals aged 15 years and above. Studies on Baltic seals during the 1970s revealed high tissue concentrations of the organochlorines bis(chlorophenyl)-1,1,1-trichloroethane (DDT) and polychlorinated biphenyls (PCBs), lowered reproduction rate, and pathologic changes. In the second half of the 1970s, decreases of PCB and DDT in Baltic biota occurred, and the prevalence of pregnancies in Baltic seals increased. Between 1975 and 1997, 53 Baltic gray seal females of age 15–40 years were found dead and sent to the Swedish Museum of Natural History. Seals were autopsied and 34/53 (64%) had uterine leiomyomas. Samples from 15 were sufficiently well preserved for histologic examination. Uterine leiomyomas were found most commonly in the uterine corpus but also were observed in the uterine horns, cervix, and vagina. Cut surfaces of the leiomyomas appeared as whorled white fibrous tissue. Histologically, spindle cells were arranged in a whorl-like pattern. The nuclei were rod-like and strikingly uniform in shape and size. Mitotic figures were rare. Immunohistochemical staining of the tumors showed a positive reaction to antibodies recognizing smooth muscle actin. Reproductively active gray seals have an ovarian corpus luteum or albicans for most of the year. In 22/34 (65%) gray seals with uterine leiomyomas, ovaries did not contain corpora. In gray seals without macroscopically detected uterine leiomyoma, ovaries from 6/19 (32%) seals had no corpora. It is possible that the development of leiomyoma in the seals is associated with organochlorines and the previous low reproductive activity.
Rhodium‐Catalyzed Hydrogenation of Alkenes by Rhodium/Tris(fluoroalkoxy)phosphane Complexes in Fluorous Biphasic System
Authors: Sinou Denis , Maillard David , Aghmiz Ali , Masdeu i‐Bultó Anna M.
Published: April 2003

The reaction of [Ir(μ‐Cl)(COD)]2 with various fluorous derivatives of triphenylphosphane containing a para‐, meta‐, or ortho‐(1H,1H‐perfluoroalkoxy)‐substituted fluorous phosphane P(C6H4‐ORf)3 (Rf=CH2C7F15, CH2CH2CH2C8F17) and CO (1 atm) gives the corresponding trans‐[Ir(μ‐Cl)(CO){P(C6H4ORf)3}2]. The IR νCO values of these complexes give some information on the donor/acceptor properties of the phosphanes. These fluorous derivatives of triphenylphosphane, as well as a phosphane bearing two (1H,1H‐perfluoroalkyloxy) chains at the 3,5‐positions, were used in association with [Rh(μ‐Cl)(COD)]2 or [Rh(COD)2]PF6 in the reduction of methyl cinnamate, 2‐cyclohexen‐1‐one, cinnamaldehyde, and methyl α‐acetamidocinnamate in a two‐phase system D‐100/ethanol under 1 bar hydrogen at room temperature. Some differences in catalytic activity were observed in the reduction of methyl cinnamate, the most active catalyst being the rhodium complex containing the phosphane with the p‐fluorous ponytail. Recycling of the fluorous catalyst was possible, particularly using the p‐substituted phosphane, where no significant loss of catalyst or activity was observed, and generally with very low leaching of rhodium or phosphane in the organic phase.
Procedural complications following diagnostic coronary angiography are related to the operator's experience and the catheter size
Authors: Ammann Peter , Brunner‐La Rocca Hans P. , Angehrn Walter , Roelli Hans , Sagmeister Markus , Rickli MD Hans
Published: April 2003

Cardiac catheterization is performed routinely in hospitals all around the world. Extensive analysis of complications has been performed in the 1980s and early 1990s. However, because of the new therapeutic innovations based on advanced catheter technologies, these data may not apply to the present situation. Still, there are few data about procedural complications of diagnostic cardiac catheterization over the last 10 years. A total of 7,412 consecutive diagnostic cardiac catheterizations were performed between January 1990 and December 2000 and prospectively assessed in a registry. There were a total of 63 complications, of which 40 were minor and 23 major. Thus, the overall complication rate was 0.8%, with a mortality rate of 0%. Univariate analysis showed lower overall complication rate of senior physicians (> 500 coronary angiographies performed; OR = 0.58; 95% CI = 0.34–0.98; P = 0.04), smaller catheter size (< 6, 6, > 6 Fr: OR = 2.6; 95% CI = 1.53–4.41; P = 0.0004), and a higher rate in patients having left and right heart catheterization (OR = 2.62; 95% CI = 1.46–4.7; P = 0.003). Major complications were associated with larger catheters (< 6, 6, > 6 Fr: OR = 2.35; 95% CI = 1.0–5.51; P = 0.05), whereas vascular complications occurred more often with higher body weight (per 10 kg: OR = 1.4; 95% CI = 1.01–1.95; P = 0.04). Overall complication rate in diagnostic coronary angiography is very low and related to the experience of the performing cardiologist and catheter size. The only predicting risk factors for major complications in coronary angiography were catheter size and body weight. Cathet Cardiovasc Intervent 2003;59:13–18. © 2003 Wiley‐Liss, Inc.
Carbon−Carbon Bond Formation with Electrogenerated Nickel and Palladium Complexes
Authors: Duñach Elisabet , Franco Delphine , Olivero Sandra
Published: April 2003

We report coupling reactions of organic derivatives through catalysis by nickel and palladium complexes combined with electrochemical methods. Arylation, carboxylation, carbonylation, cyclisation, alkylation, and other reductive C−C bond forming reactions of organic halide derivatives, unsaturated hydrocarbons, and carbonyl derivatives, are presented. This review highlights electrosynthesis as an alternative methodology in the field of synthesis and catalysis. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)
A critique of the World Health Organisation's evaluation of health system performance
Authors: Richardson Jeff , Wildman John , Robertson Iain K.
Published: April 2003

The World Health Organisation's (WHO) approach to the measurement of health system efficiency is briefly described. Four arguments are then presented. First, equity of finance should not be a criterion for the evaluation of a health system and, more generally, the same objectives and importance weights should not be imposed upon all countries. Secondly, the numerical value of the importance weights do not reflect their true importance in the country rankings. Thirdly, the model for combining the different objectives into a single index of system performance is problematical and alternative models are shown to alter system rankings. The WHO statistical analysis is replicated and used to support the fourth argument which is that, contrary to the author's assertion, their methods cannot separate true inefficiency from random error. The procedure is also subject to omitted variable bias. The econometric model for all countries has very poor predictive power for the subset of OECD countries and it is outperformed by two simpler algorithms. Country rankings based upon the model are correspondingly unreliable. It is concluded that, despite these problems, the study is a landmark in the evolution of system evaluation, but one which requires significant revision. Copyright © 2002 John Wiley & Sons, Ltd.
X‐ray structural analysis of the ligand‐recognition mechanism in the dual‐affinity labeling of c‐type lysozyme with 2′,3′‐epoxypropyl β‐glycoside of N‐acetyllactosamine
Authors: Muraki Michiro , Harata Kazuaki
Published: April 2003

In spite of the belonging to the same c‐type lysozyme family, hen egg‐white lysozyme (HEWL) was much less susceptible to the dual‐affinity labeling with 2′,3′‐epoxypropyl β‐glycoside of N‐acetyllactosamine (Galβ1,4GlcNAc‐Epo) than human lysozyme (HL). The three‐dimensional structures of the HEWL labeled with single Galβ1,4GlcNAc‐Epo and the Glu102‐mutant HL labeled with double Galβ1,4GlcNAc‐Epo were determined by X‐ray crystallography at resolutions of 1.85 and 2.0 Å, respectively. The overall conformation and the interaction mode of the carbohydrate ligand part in the singly labeled HEWL and the doubly labeled Glu102‐mutant HL were basically identical to those of the correspondingly labeled wild‐type HL with minor alterations in some stereochemical parameters. A detailed comparison of the structures revealed the key protein–carbohydrate and carbohydrate–carbohydrate interactions essential for the dual labeling. It was suggested that the difference in the efficiency of the dual labeling was caused by the structural difference between Gln104 in HL and Asn103 in HEWL. The relevance to our previous study and the carbohydrate–carbohydrate interaction on cell‐surface membranes were discussed. Copyright © 2003 John Wiley & Sons, Ltd.