Multicentric lymphoma in a donkey with intestinal and bone marrow involvement.

BACKGROUND: Lymphoma is a common neoplasm in horses but is reported much less commonly in donkeys. In this case report, we describe the macroscopic, microscopic and immunohistochemical features of a multicentric lymphoma with intestinal and bone marrow involvement. CASE PRESENTATION: A geriatric female donkey with history of chronic lameness was found dead. Post-mortem examination revealed advanced emaciation, periodontal disease, left front foot laminitis and multiple, soft, white to yellow tan intestinal transmural masses, up to 12 cm in diameter. Cytology suggested a round cell intestinal neoplasm. The femur of the left hint limb was double the size of the normal contralateral, with suspected neoplastic infiltration and replacement of bone marrow and bone. Histologically we diagnosed a lymphoma in the intestine and left femur. Immunohistochemically, the neoplastic cells showed CD3 immunolabelling, supporting a diagnosis of a multicentric T-cell lymphoma. CONCLUSIONS: To the authors' knowledge, this is the first time multicentric lymphoma is diagnosed in donkeys. Further studies of the genetic background, clinical, laboratory, histopathologic, and immunohistochemical, as well as the pathogenesis of lymphoma, is needed to better understand the uniquely low frequency of this neoplasm in donkeys.

Fluorescent In Situ Hybridization for the Detection of Intracellular Bacteria in Companion Animals.

FISH techniques have been applied for the visualization and identification of intracellular bacteria in companion animal species. Most frequently, these techniques have focused on the identification of adhesive-invasive Escherichia coli in gastrointestinal disease, although various other organisms have been identified in inflammatory or neoplastic gastrointestinal disease. Previous studies have investigated a potential role of Helicobacter spp. in inflammatory gastrointestinal and hepatic conditions. Other studies evaluating the role of infectious organisms in hepatopathies have received some attention with mixed results. FISH techniques using both eubacterial and species-specific probes have been applied in inflammatory cardiovascular, urinary, and cutaneous diseases to screen for intracellular bacteria. This review summarizes the results of these studies.

Evaluation of parasitic infections with histological and molecular detection in Anoles from St. Kitts.

Anoles are a widely distributed group of reptiles that are also increasing in popularity as a pet animal. These species have been described as paratenic and intermediate hosts for many parasites of veterinary and medical importance. However, while human and animals such as cats and dogs may often interact with anoles, little research has been conducted in terms of assessing the full potential of anoles to harbor parasites of public and veterinary health significance. The current study analyzed the parasites of anoles captured and dissected in St. Kitts, West Indies, to describe the parasitic population within these reptiles and evaluate the potential role of anoles as intermediate/paratenic hosts. From March until May of 2019, samples from 11 anoles were collected following humane euthanasia and evaluated grossly, histologically, and molecularly for the presence of parasites. Histologic evaluation revealed adult ascarids, oxyurids, and spirurids within the stomach, as well as intraluminal adult ascarids within the intestine, and encysted larval trematodes within the intestinal wall. Molecular analysis based on 18S rRNA and ITS2 DNA markers for nematodes and trematodes, respectively, identified Physaloptera sp. (99.4-99.8% identical with Physaloptera turgida, Physaloptera mirandai, Physaloptera retusa, Physaloptera rara) and Platynosomum illiciens (99.7% identical). Phylogenetic analysis of ITS 2 sequences of P. illiciens from this study cladded monophyletically with the same species from different geographic areas and hosts. Our study highlights the importance of understanding the role anoles play in the life cycles of less well-studied parasites, and the potential of these animals to act as intermediate or paratenic hosts.

Anatomical, Histological, and Morphometrical Investigations of the Auditory Ossicles in Chlorocebus aethiops sabaeus from Saint Kitts Island.

Otological studies rely on a lot of data drawn from animal studies. A lot of pathological or evolutionary questions may find answers in studies on primates, providing insights into the morphological, pathological, and physiological aspects of systematic biological studies. Our study on auditory ossicles moves from a pure morphological (macroscopic and microscopic) investigation of auditory ossicles to the morphometrical evaluation of several individuals as well as to some interpretative data regarding some functional aspects drawn from these investigations. Particularities from this perspective blend with metric data and point toward comparative elements that might also serve as an important reference in further morphologic and comparative studies.

Histology, prevalence, and environmental sources for pulmonary silicates depositions in domestic and wild animals.

The source and significance of pulmonary silicate crystals in animals and people are poorly understood. To estimate the prevalence and characterize the pulmonary crystalline material in animals from St. Kitts, tissue samples from dogs, horses, cattle, sheep, goats, pigs, chickens, mongooses, and monkeys were examined by light microscopy, scanning electron microscopy with energy-dispersive x-ray analysis (SEM/EDXA), and x-ray diffraction. Crystalline material was seen in 201 of 259 (77.6%) lung samples as perivascular and interstitial accumulations of heterogeneous crystalline particulate material, free or within macrophages (silicate-laden macrophages [SLMs]), mostly lacking evidence of chronic inflammation or fibrosis. The crystalline material was birefringent, basophilic on acid-fast, and composed of silicas on SEM/EDXA. Mongooses (100%) and monkeys (98%) had the highest prevalence of SLM, followed by cattle and chickens. Lesions were graded on a 3-point scale based on the histologic location and extent of silicates and SLM and were significantly more severe in mongooses (median = 3) than in monkeys (median = 2), dogs (median = 2), and chickens (median = 1). On EDXA, the crystalline material from lungs, air, and topsoil was composed of silicon, oxygen, aluminum, and iron, with a particulate matter size between 2.5 and 10 µm. We hypothesize Saharan dust, volcanic ash, topsoil, and rock quarry dust are potential sources of siliceous dust inhalation and SLM accumulations lacking chronic inflammation (silicosis); dust generation may be potentiated by road vehicle or wind suspension. Future investigations are warranted on the role of silicate inhalation and respiratory comorbidities in people, with monkeys, mongooses, or chickens serving as possible sentinels for exposure.

Mitosis domain generalization in histopathology images - The MIDOG challenge.

The density of mitotic figures (MF) within tumor tissue is known to be highly correlated with tumor proliferation and thus is an important marker in tumor grading. Recognition of MF by pathologists is subject to a strong inter-rater bias, limiting its prognostic value. State-of-the-art deep learning methods can support experts but have been observed to strongly deteriorate when applied in a different clinical environment. The variability caused by using different whole slide scanners has been identified as one decisive component in the underlying domain shift. The goal of the MICCAI MIDOG 2021 challenge was the creation of scanner-agnostic MF detection algorithms. The challenge used a training set of 200 cases, split across four scanning systems. As test set, an additional 100 cases split across four scanning systems, including two previously unseen scanners, were provided. In this paper, we evaluate and compare the approaches that were submitted to the challenge and identify methodological factors contributing to better performance. The winning algorithm yielded an F1 score of 0.748 (CI95: 0.704-0.781), exceeding the performance of six experts on the same task.

Molecular Investigation of Canine Parvovirus-2 (CPV-2) Outbreak in Nevis Island: Analysis of the Nearly Complete Genomes of CPV-2 Strains from the Caribbean Region.

To date, there is a dearth of information on canine parvovirus-2 (CPV-2) from the Caribbean region. During August-October 2020, the veterinary clinic on the Caribbean island of Nevis reported 64 household dogs with CPV-2-like clinical signs (hemorrhagic/non-hemorrhagic diarrhea and vomiting), of which 27 animals died. Rectal swabs/fecal samples were obtained from 43 dogs. A total of 39 of the 43 dogs tested positive for CPV-2 antigen and/or DNA, while 4 samples, negative for CPV-2 antigen, were not available for PCR. Among the 21 untested dogs, 15 had CPV-2 positive littermates. Analysis of the complete VP2 sequences of 32 strains identified new CPV-2a (CPV-2a with Ser297Ala in VP2) as the predominant CPV-2 on Nevis Island. Two nonsynonymous mutations, one rare (Asp373Asn) and the other uncommon (Ala262Thr), were observed in a few VP2 sequences. It was intriguing that new CPV-2a was associated with an outbreak of gastroenteritis on Nevis while found at low frequencies in sporadic cases of diarrhea on the neighboring island of St. Kitts. The nearly complete CPV-2 genomes (4 CPV-2 strains from St. Kitts and Nevis (SKN)) were reported for the first time from the Caribbean region. Eleven substitutions were found among the SKN genomes, which included nine synonymous substitutions, five of which have been rarely reported, and the two nonsynonymous substitutions. Phylogenetically, the SKN CPV-2 sequences formed a distinct cluster, with CPV-2b/USA/1998 strains constituting the nearest cluster. Our findings suggested that new CPV-2a is endemic in the region, with the potential to cause severe outbreaks, warranting further studies across the Caribbean Islands. Analysis of the SKN CPV-2 genomes corroborated the hypothesis that recurrent parallel evolution and reversion might play important roles in the evolution of CPV-2.

International Guidelines for Veterinary Tumor Pathology: A Call to Action.

Standardization of tumor assessment lays the foundation for validation of grading systems, permits reproducibility of oncologic studies among investigators, and increases confidence in the significance of study results. Currently, there is minimal methodological standardization for assessing tumors in veterinary medicine, with few attempts to validate published protocols and grading schemes. The current article attempts to address these shortcomings by providing standard guidelines for tumor assessment parameters and protocols for evaluating specific tumor types. More detailed information is available in the Supplemental Files, the intention of which is 2-fold: publication as part of this commentary, but more importantly, these will be available as "living documents" on a website (www.vetcancerprotocols.org), which will be updated as new information is presented in the peer-reviewed literature. Our hope is that veterinary pathologists will agree that this initiative is needed, and will contribute to and utilize this information for routine diagnostic work and oncologic studies. Journal editors and reviewers can utilize checklists to ensure publications include sufficient detail and standardized methods of tumor assessment. To maintain the relevance of the guidelines and protocols, it is critical that the information is periodically updated and revised as new studies are published and validated with the intent of providing a repository of this information. Our hope is that this initiative (a continuation of efforts published in this journal in 2011) will facilitate collaboration and reproducibility between pathologists and institutions, increase case numbers, and strengthen clinical research findings, thus ensuring continued progress in veterinary oncologic pathology and improving patient care.

A study of oxidative stress and pulmonary damage after silica instillation in rats and the effect of curcumin administration.

BACKGROUND: The authors' aim was to study the dynamics of oxidative stress in experimental exposure to silica dust, to evaluate the histopathological findings in the phase preceding the formation of fibrous/fibrohyaline pulmonary nodules, and to assess the effects of curcumin administration. MATERIAL AND METHODS: The research was performed on 48 male Wistar rats with an average weight of 320 g. Overall, 38 rats were instilled with a single dose of 0.3 ml suspension containing 30 mg of a SiO2/ml saline solution, and were sacrificed 30, 90 and 120 days after instillation; 14 of those sacrificed on days 90 and 120 also received curcumin. The control group included 10 animals which were instilled with a saline solution. Malondialdehyde (MDA), carbonyl proteins (CPs), total thiolic proteins (TPs) and reduced glutathione (GSH) were determined in blood and the lung tissue. The standard technique for pulmonary toxicology developed by Porter was applied to semi-quantitatively assess the histopathological findings. RESULTS: It was found that MDA had increased significantly early on in both biological environments and remained elevated, and adding curcumin proved beneficial, while CPs only increased moderately in the lung tissue without a curcumin impact. Moreover, TPs dropped abruptly, significantly and persistently in the lung tissue and blood, and were not influenced by curcumin. Finally, GSH decreased significantly and intensely in the lung tissue and blood, with curcumin lowering the levels towards those found within the control group. The histopathological examination identified nodules of a cellular type, without any fibrosis, but with spots of associated lipoproteinosis. The early lesions in the airways and vessels were suggestive of a remodeling process. Curcumin diminished the occurrence of alveolitis but not the remodeling process. CONCLUSIONS: The study confirms the early onset of oxidative stress in experimental silicosis. It also simultaneously and dynamically researches markers of oxidative stress in blood and the lung tissue. Curcumin proved beneficial on oxidative stress and lesions in the alveolar epithelia, but ineffective in preventing vascular and airway remodeling. Med Pr. 2021;72(3):239-47.

Development and Application of an Interactive Neuropathology iBook as a Complementary Learning Tool for Veterinary Medicine Students.

Neuropathology is a challenging subject for most medical students. Delivering a gamified learning tool on this topic may motivate students and increase knowledge in the discipline. We report the development of such a tool in iBook format for the systemic pathology course delivered at Ross University School of Veterinary Medicine. Composed of 10 chapters (cases), this Neuropathology iBook (NP-iB) reviews basic clinical manifestations, neuropathology, and pathogenesis of common non-neoplastic conditions that cause brain disease in domestic animals. The goal of each chapter is to reach a diagnosis by interactively answering specific questions after reviewing relevant medical history, clinical pathology, and autopsy findings. Our hypothesis: the NP-iB improves students' ability to recognize these diseases, reflected in higher test scores. Using a post-test only control group design, data were gathered from all students enrolled in the course in two different semesters, fall 2017 and spring 2018 (n = 300). NP-iB users (n = 51, 17%) and usage time were identified by answers to multiple-choice questions embedded in the course assessments. Ninety percent of users had a positive perception although no statistically significant differences were found in median test scores between users and non-users. Statistically significant test score differences were found across how much time students used the NP-iB (p = .005); the lowest test score median values were found for neuropathology questions not related to the NP-iB, in students who used it for more than 3 hours. Unexpectedly, a low number of students preferred this digital learning tool, and its use did not improve their learning outcomes.

Ligature induced periodontitis causes atherosclerosis in rat descending aorta: an experimental study.

INTRODUCTION: In recent years a link between periodontitis and cardiovascular diseases has been proposed. Oxidative stress has been found to be involved in their pathophysiology. OBJECTIVES: The aim of this study was to demonstrate that a wire ligature placed around the first mandibular molars of the rat causes inflammation in the periodontium and lipid deposits in the aorta, via oxidative stress. METHODS: Twenty male Wistar rats were divided randomly into two groups of 10: Control group and Periodontitis group. An orthodontic wire ligature was placed around the cervix of the first mandibular molar and was kept in place for 4 weeks. Clinical attachment loss was determined to assess the gingival recession. Aorta was harvested after 4 weeks and the malondialdehyde (MDA) levels in the aorta tissue homogenate were determined. Lipid deposits were evaluated using Oil Red staining and immunofluorescence under confocal microscopy. Total lipid deposits in the aorta were assessed using a computer morphometry system. RESULTS: Significant gingival recession was observed in the Periodontitis group in comparison with the Control group. Increased MDA levels were present in the aorta in the ligatured rats in comparison with the Control group. Significant lipid deposits were observed in the aorta of the Periodontitis group as opposed to the Control group. CONCLUSIONS: The affixing of an orthodontic wire ligature produces gingival recession, increased oxidative stress and lipid deposits in the rat descending aorta.

Clinical and Pathological Features in Horses With Advanced Arytenoid Chondritis.

Equine arytenoid chondritis causes airway obstruction and abnormal upper airway noise due to a space-occupying lesion(s) and decreased abduction. Our objective was to compare clinical scores and ultrasonographic findings with gross and microscopic lesions of naturally occurring arytenoid chondritis, in order to guide surgical treatment. Seventeen naturally affected horses with advanced/severe chronic arytenoid chondritis and 4 control arytenoid cartilages were evaluated after partial arytenoidectomy. Cartilages were sectioned caudal to the corniculate process and the body of each arytenoid was measured. We assessed total gross area (TA), percentage of viable cartilage (VC), percentage of viable cartilage on the lateral wall, and medial expansion. Retrospectively, the gross lesions were used to suggest 2 preferred surgical management (SM) groups: those requiring partial arytenoidectomy and those amendable to focal medial resection (a conservative SM). TA of horses with arytenoid chondritis was significantly larger than controls (P = .005), due to a layered lesion composed of cavitation, granulation tissue, fibrosis, inflammation, hemorrhage, and edema, with relatively equal medial and lateral expansion that distorted the geometry of the affected cartilage. The increased TA paralleled the presence of immature cartilage with disorganized primitive mesenchymal cells. TA and SM were positively correlated (P = .01). All cases showed varying degrees of cartilage degeneration or necrosis, more severe medially; those appearing amenable to focal medial resection arytenoid group had significantly more viable cartilage on the lateral wall (P = .02). The gross and histopathologic findings suggest a new surgical approach-focal medial resection-that may save the lateral wall of the arytenoid.

Mitotic Figures-Normal, Atypical, and Imposters: A Guide to Identification.

Counting mitotic figures (MF) in hematoxylin and eosin-stained histologic sections is an integral part of the diagnostic pathologist's tumor evaluation. The mitotic count (MC) is used alone or as part of a grading scheme for assessment of prognosis and clinical decisions. Determining MCs is subjective, somewhat laborious, and has interobserver variation. Proposals for standardizing this parameter in the veterinary field are limited to terminology (use of the term MC) and area (MC is counted in an area measuring 2.37 mm2). Digital imaging techniques are now commonplace and widely used among veterinary pathologists, and field of view area can be easily calculated with digital imaging software. In addition to standardizing the methods of counting MF, the morphologic characteristics of MF and distinguishing atypical mitotic figures (AMF) versus mitotic-like figures (MLF) need to be defined. This article provides morphologic criteria for MF identification and for distinguishing normal phases of MF from AMF and MLF. Pertinent features of digital microscopy and application of computational pathology (CPATH) methods are discussed. Correct identification of MF will improve MC consistency, reproducibility, and accuracy obtained from manual (glass slide or whole-slide imaging) and CPATH approaches.

Leptospira Infection in African Green Monkeys in an Endemic Area: An Opportunity for Comparative Studies in a Natural Environment.

This study was performed to investigate the potential asymptomatic Leptospira reservoir status among African green monkeys (AGMs) in the Caribbean island of Saint Kitts, and whether there is any renal pathology associated with Leptospira exposure. Forty-eight percent of AGMs tested were positive for Leptospira antibodies by the microscopic agglutination test. Leptospira DNA was detected in 4% of kidney samples tested using a lipl32 gene based PCR. We observed minimal to severe microscopic renal lesions in 85% of the AGM kidneys evaluated. The majority of the AGMs (n = 26) had only minimal to mild interstitial nephritis and a few (n = 3) had moderate to severe lesions. The presence of interstitial nephritis was not significantly associated with Leptospira exposure. The presence of infected AGMs in a small surface limited geographic region may pose zoonotic threat to humans and animals. The impact of Leptospira infection in renal pathology in AGMs warrants further investigation. AGMs residing in a natural setting in an insular, surface limited Leptospira endemic geographic region may offer opportunities for comparative studies to advance the field of leptospirosis. Due to their similarity to humans, such studies in AGMs may also provide translational opportunities to advance Leptospira research.

Modulatory effects of Cornus sanguinea L. mediated green synthesized silver nanoparticles on oxidative stress, COX-2/NOS2 and NFkB/pNFkB expressions in experimental inflammation in Wistar rats.

The present study presents a green, cost efficient and easy synthesis method of silver nanoparticles (AgNPs) using an aqueous extract of Cornus sanguinea L. fruits (CS). The phytosynthesized silver nanoparticles were characterized using various analytical techniques such as UV-Vis absorption spectroscopy, which confirmed the formation of AgNPs and FTIR spectroscopy, in order to certify the role of the biomolecules present in the fruit extract as reducing and capping agents of the AgNPs. The UV-Vis absorption spectrum showed a broad band at 407 nm characteristic for colloidal silver. Transmission electron microscopy was conducted to investigate the shape and size of the silver nanoparticles, revealing a spherical shape with an average particle size of 18 nm. The antioxidant and anti-inflammatory activities of the fruit extract and green synthesized silver nanoparticles were assessed in vivo on experimental inflammation. The obtained results showed that CS and AgNPs reduced oxidative stress in parallel with increasing of antioxidant defense and diminished the COX-2 expressions. CS extract had a dual effect on NFkB activation depending on the time of testing while AgNPs increased NFkB phosphorylation at 48 h. These results suggested that both AgNPs and CS extract exhibited antioxidant and anti-inflammatory activities but with a different dynamics of action.

Grape Seed Extract Reduces the Degree of Atherosclerosis in Ligature-Induced Periodontitis in Rats - An Experimental Study.

The associations between periodontitis and cardiovascular diseases have been intensely studied in recent years. Oxidative stress is involved in the initiation and both progression of periodontitis and atherosclerosis. Antioxidants can reduce the effects of oxidative stress on inflammatory diseases. Our aim was to measure the effects of a grape seed extract (GSE), rich in antioxidants, on atherosclerosis caused by ligature-induced periodontitis in rats. Thirty male Wistar rats were randomly divided into three groups of 10: control group, periodontitis group, and periodontitis group treated with GSE (GSE group). Periodontitis was induced by placing an orthodontic wire around the cervix of the first mandibular molar and keeping it in place for 4 weeks. On days 1, 7 and 28, blood samples were taken to assess oxidative stress and inflammation markers (malondialdehyde and glutathione - MDA, reduced glutathione - GSH, C reactive protein) and lipids. After 4 weeks, the animals were euthanized, and aortas were collected for histopathologic examination. MDA was significantly higher in Periodontitis group compared to the other groups only at day 7. GSH was significantly increased in the Control and GSE groups on days 1 and 7, compared to Periodontitis group and on day 28 higher in GSE vs. Periodontitis groups. C reactive protein was significantly increased in the Periodontitis group on days 1 and 7 compared to both groups. Cholesterol was significantly decreased in the aortas of GSE group at day 28 compared to the Periodontitis group. Oral administration of a grape seed extract reduces the oxidative stress, inflammation and atherosclerosis in a rat model of ligature-induced periodontitis.

Cutaneous Pyogranulomas Associated with Nocardia jiangxiensis in a Cat from the Eastern Caribbean.

Nocardia spp. are worldwide, ubiquitous zoonotic bacteria that have the ability to infect humans as well as domestic animals. Herein, we present a case of a five-year-old female spayed domestic shorthair cat (from the island of Nevis) with a history of a traumatic skin wound on the ventral abdomen approximately two years prior to presenting to the Ross University Veterinary Clinic. The cat presented with severe dermatitis and cellulitis on the ventral caudal abdomen, with multiple draining tracts and sinuses exuding purulent material. Initial bacterial culture yielded Corynebacterum spp. The patient was treated symptomatically with antibiotics for 8 weeks. The cat re-presented 8 weeks after the initial visit with worsening of the abdominal lesions. Surgical intervention occurred at that time, and histopathology and tissue cultures confirmed the presence of Nocardia spp.-induced pyogranulomatous panniculitis, dermatitis, and cellulitis. Pre-operatively, the patient was found to be feline immunodeficiency virus (FIV)-positive. The patient was administered trimethoprim/sulfamethoxazole (TMS) after antimicrobial sensitivity testing. PCR amplification and 16S rRNA gene sequencing confirmed Nocardia jiangxiensis as the causative agent. To our knowledge, N. jiangxiensis has not been previously associated with disease. This case report aims to highlight the importance of a much-needed One Health approach using advancements in technology to better understand the zoonotic potential of Nocardia spp. worldwide.

Hereditary ß-mannosidosis in a dog: Clinicopathological and molecular genetic characterization.

Hereditary ß-mannosidosis causing progressive lysosomal neuropathy and other clinical signs, has been previously described in humans, Nubian goats, and Salers cattle. Here we report the clinicopathological, metabolic, and molecular genetic features of canine beta-mannosidase (MANBA, EC 3.2.1.25) deficiency. A 1-year-old male mix-breed dog from St. Kitts was presented with progressive stumbling, weakness, and regurgitation. Vacuolated lymphocytes were observed on the blood film. Postmortem findings included marked enlargement of nerves, megaesophagus, and internal hydrocephalus. Vacuolated macrophages, neurons, and secretory epithelial cells suggested an oligosaccharide storage disease. Plasma concentration of the ß-mannosidosis specific oligosaccharide was approximately 75 fold that of controls. The plasma beta-mannosidase activity was severely reduced to ~5% of controls; five other lysosomal acid hydrolase activities were increased or within their normal reference interval. Genomic sequencing of this dog's MANBA gene identified a homozygous exonic five bp tandem duplication in the penultimate exon of the MANBA gene (c.2377_2381dupTATCA) which results in a reading frame shift, altering the subsequent amino acid sequence and creating a premature stop codon. The truncated beta-mannosidase enzyme is expected to be dysfunctional. This enzyme deficiency causes the accumulation of un-degraded oligosaccharides in cells, which affect the myelination of the peripheral and central nervous systems. This insertion was not encountered in 121 and 80-screened samples from dogs on St. Kitts (all were homozygous for wild-type) and Philadelphia region (wild-type), respectively. In conclusion, canine ß-mannosidosis has similar clinicopathological features with some human patients, but milder signs than in ruminants and more severe than in knockout mice. Hence, dogs with ß-mannosidosis could become a valuable disease model for the human disease.