Publications by authors named "Gerald E Duhamel"

Article Synopsis
  • Tick-borne infections, particularly Lyme disease, are on the rise in the U.S. and globally, with varying severity from mild to severe symptoms.
  • In a study using susceptible B6 mice, co-infection with Lyme disease and another pathogen caused significant inflammatory responses and joint inflammation, unlike single infections.
  • The results indicate that co-infection can worsen Lyme disease's impact, leading to more severe inflammation and joint issues.
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Differentiating canine acanthomatous ameloblastoma (CAA) from oral squamous cell carcinoma (OSCC) based on routine histopathology can be challenging. We have previously shown that more than 95% of CAAs harbor an p.Q61R somatic mutation, while OSCCs carry either wild-type alleles or other MAPK pathway activating mutations (e.

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  • - Equine herpesvirus-5 (EHV-5) is often found in healthy horses but may be linked to diseases like equine multinodular pulmonary fibrosis (EMPF) and interface dermatitis, though the exact cause is unclear.
  • - Researchers studied a database for equine interface dermatitis cases from 2007 to 2022, identifying 10 cases, with viral inclusion bodies found in 5 of them, alongside two similar cases from another lab.
  • - Seven horses exhibited chronic facial dermatitis, showing specific histological signs related to EHV-5, which was confirmed through various tests, marking the first reported cases of this condition associated with the virus in the U.S.
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Background And Purpose: COVID-19 infections caused by SARS-CoV-2 disseminated through human-to-human transmission can evoke severe inflammation. Treatments to reduce the SARS-CoV-2-associated inflammation are needed and are the focus of much research. In this study, we investigated the effect of N-ethyl-N'-[(3β,5α)-17-oxoandrostan-3-yl] urea (NEOU), a novel 17α-ketosteroid derivative, on the severity of COVID-19 infections.

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  • * Abdominal ultrasound showed serious issues like swollen lymph nodes and a significant mass in the colon, which later revealed a fistula created by the mass invading the colon walls.
  • * The case was notable because it's the first reported instance of a trans-colonic fistula from alimentary lymphoma in a horse and the detection of equid herpesvirus 5 in relation to this condition.
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Article Synopsis
  • Oral squamous cell carcinoma (OSCC) is a highly aggressive form of oral cancer in dogs with a 0% one-year survival rate when untreated.
  • The study indicates that a significant percentage (up to 85.7%) of canine papillary OSCC tumors have a specific BRAF mutation, supporting its role in tumor development.
  • Findings from the research could lead to improved diagnostic methods and targeted therapies for this cancer type, enhancing veterinary care for affected dogs.
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Case Description: Outbreaks of sudden death in apparently healthy weaned dairy calves due to Strongyloides papillosus parasitism were diagnosed on 2 separate and independent New York (NY) dairies.

Clinical Findings: Most calves were found dead; however, 1 calf observed while dying showed signs of tachycardia, tachypnea, vocalization, and convulsions shortly before death. In 6 affected heifers that underwent post-mortem examination, precocious bilaterally symmetric mammary gland enlargement was seen.

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Intestinal lacteals are essential lymphatic channels for absorption and transport of dietary lipids and drive the pathogenesis of debilitating metabolic diseases. However, organ-specific mechanisms linking lymphatic dysfunction to disease etiology remain largely unknown. In this study, we uncover an intestinal lymphatic program that is linked to the left-right (LR) asymmetric transcription factor Pitx2.

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Ameloblastomas are odontogenic tumors that are rare in people but have a relatively high prevalence in dogs. Because canine acanthomatous ameloblastomas (CAA) have clinicopathologic and molecular features in common with human ameloblastomas (AM), spontaneous CAA can serve as a useful translational model of disease. However, the molecular basis of CAA and how it compares to AM are incompletely understood.

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Dental and oral diseases are prevalent in many mammalian species including wild felids. Determining the dental and oral health status of captive animal populations can help establish preventive and therapeutic strategies, leading to improved welfare and conservation efforts. The aim of this study was to assess the prevalence of periodontal disease, endodontic disease, tooth resorption, and other clinically relevant dental and maxillofacial abnormalities in a population of captive jaguars () using clinical, radiographic, and histopathological findings.

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Ferret systemic coronaviral disease (FSCD) is a well-established cause of mortality in domestic ferrets. We describe herein novel findings in a case of FSCD that was diagnosed and medically managed following virus detection by immunohistochemical (IHC) staining of surgical biopsy samples. Hematologic changes in this ferret suggested spread of the virus to the bone marrow, which was confirmed by IHC staining of a postmortem sample.

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Ameloblastoma is a locally aggressive odontogenic tumour that occurs in humans and dogs. Most ameloblastomas (AM) in humans harbour mutually-exclusive driving mutations in BRAF, HRAS, KRAS, NRAS or FGFR2 that activate MAPK signalling, and in SMO that activates Hedgehog signalling. The remarkable clinical and histological similarities between canine acanthomatous ameloblastoma (CAA) and AM suggest they may harbour similar driving mutations.

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Common variable immunodeficiency (CVID) is a rare condition in adult horses characterized by hypogammaglobulinemia and increased susceptibility to parasitic and bacterial infections, including recurrent respiratory diseases, septicemia, and meningitis. Lyme disease is often included as a differential diagnosis in CVID horses with signs of meningitis; however, the Borrelia burgdorferi organism has not been demonstrated previously within central nervous system tissues of CVID horses with neurologic disease, to our knowledge. We report herein a case of neuroborreliosis in a CVID horse, confirmed by combined immunologic testing, histopathology, real-time PCR assay, fluorescent in situ hybridization, and immunohistochemical staining.

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The cytolethal distending toxin (S-CDT), first described as the "typhoid toxin" in subsp. serotype Typhi, induces DNA damage in eukaryotic cells. Recent studies have shown that more than 40 nontyphoidal (NTS) serotypes carry genes that encode S-CDT, yet very little is known about the activity, function, and role of S-CDT in NTS.

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Article Synopsis
  • Researchers isolated a calicivirus similar to the vesivirus 2117 strains, confirming its presence in the deceased dogs' tissues, particularly affecting blood vessel cells and causing significant necrosis and hemorrhage in the intestines and brain.
  • This incident marks the first documentation of a severe disease associated with a previously less harmful vesivirus strain in dogs, raising concerns about the origins and potential spread of these canine vesiviruses.
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An 11 yr old spayed female domestic longhair cat was presented for an acute onset of vomiting. Abdominal radiographs and ultrasound revealed severe gastric dilatation (GD) without evidence of gastric outflow obstruction. On esophagogastroduodenoscopy, the duodenal mucosa was mildly erythematous, and a moderate, diffuse, chronic enteritis was found by histological examination of duodenal biopsies.

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Article Synopsis
  • - Horses can develop gastric ulcers (EGUS), similar to humans, affecting their performance and increasing care costs; however, a bacterial cause has not been definitively found.
  • - The study investigates equid gammaherpesviruses (EHV-2 and EHV-5) in horse gastric tissue, showing they exist in the gastric mucosa but not directly linking them to EGUS in the small sample studied.
  • - Results suggest that these herpesviruses co-infect the gastric epithelium of horses, highlighting the need for further research to understand their potential role in gastric ulcers and gastrointestinal diseases.
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Salmonella enterica subsp. enterica serovar Dublin ( Salmonella Dublin) is a host-adapted bacterium that causes high morbidity and mortality in dairy cattle worldwide. A retrospective search of archives at the New York Animal Health Diagnostic Center revealed 57 culture-confirmed Salmonella Dublin cases from New York and Pennsylvania in which detailed histology of multiple tissues was available.

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Inflammatory bowel disease (IBD) is an incurable chronic idiopathic disease that drastically decreases quality of life. Endoplasmic reticulum (ER)-associated degradation (ERAD) is responsible for the clearance of misfolded proteins; however, its role in disease pathogenesis remains largely unexplored. Here we show that the expression of SEL1L and HRD1, the most conserved branch of mammalian ERAD, is significantly reduced in ileal Crohn's disease (CD).

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Endoplasmic reticulum (ER)-associated degradation (ERAD) represents a principle quality control mechanism to clear misfolded proteins in the ER; however, its physiological significance and the nature of endogenous ERAD substrates remain largely unexplored. Here we discover that IRE1α, the sensor of the unfolded protein response (UPR), is a bona fide substrate of the Sel1L-Hrd1 ERAD complex. ERAD-mediated IRE1α degradation occurs under basal conditions in a BiP-dependent manner, requires both the intramembrane hydrophilic residues of IRE1α and the lectin protein OS9, and is attenuated by ER stress.

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