Mutations in RABL3 alter KRAS prenylation and are associated with hereditary pancreatic cancer.

Pancreatic ductal adenocarcinoma is an aggressive cancer with limited treatment options1. Approximately 10% of cases exhibit familial predisposition, but causative genes are not known in most families2. We perform whole-genome sequence analysis in a family with multiple cases of pancreatic ductal adenocarcinoma and identify a germline truncating mutation in the member of the RAS oncogene family-like 3 (RABL3) gene. Heterozygous rabl3 mutant zebrafish show increased susceptibility to cancer formation. Transcriptomic and mass spectrometry approaches implicate RABL3 in RAS pathway regulation and identify an interaction with RAP1GDS1 (SmgGDS), a chaperone regulating prenylation of RAS GTPases3. Indeed, the truncated mutant RABL3 protein accelerates KRAS prenylation and requires RAS proteins to promote cell proliferation. Finally, evidence in patient cohorts with developmental disorders implicates germline RABL3 mutations in RASopathy syndromes. Our studies identify RABL3 mutations as a target for genetic testing in cancer families and uncover a mechanism for dysregulated RAS activity in development and cancer.

Histopathology and external examination of heavily parasitized Lost River Sucker Deltistes luxatus (Cope 1879) and Shortnose Sucker Chasmistes brevirostris (Cope 1879) from Upper Klamath Lake, Oregon.

Shortnose Sucker (Chasimistes brevirostris) and Lost River Sucker (Deltistes luxatus) are endemic to the Upper Klamath Basin of Southern Oregon and Northern California, and their populations are in decline. We used histopathology and external examination of 140 and external examination only of 310 underyearling suckers collected in 2013, 2015 and 2016 to document pathological changes, particularly those relating to parasites. The most severe infection was caused by a Contracaecum sp., infecting the atrium of 8%-33% of Shortnose Suckers. The most prevalent infections were caused by Bolbophorus sp. metacercariae in the muscle of Shortnose Suckers (21%-63%) and Lernaea cyprinacea in the skin and muscle of Lost River Suckers (30%-81%). Histology detected Bolbophorus in only 5% of cases where it was not seen externally. Three myxozoans were observed; a Parvicapsula sp. in the renal tubules (10%), a Myxobolus sp. in the intestinal mucosa (2%) and an unusual multicellular, presporogonic myxozoan in the intestinal lumen of one sucker. Severe gill epithelial hyperplasia was observed in several fish collected in 2016. Trichodinids and Ichthyobodo sp. were observed on some of the gills, but absent in many of the fish with severe lesions. A histiocytic sarcoma was observed in sucker.

The effects of venting and decompression on Yellow Tang (Zebrasoma flavescens) in the marine ornamental aquarium fish trade.

Each year, over 45 countries export 30 million fish from coral reefs as part of the global marine ornamental aquarium trade. This catch volume is partly influenced by collection methods that cause mortality. Barotrauma in fish resulting from forced ascent from depth can contribute to post-collection mortality. However, implementing decompression stops during ascent can prevent barotrauma. Conversely, venting (puncturing the swim bladder to release expanded internal gas) following ascent can mitigate some signs of barotrauma like positive buoyancy. Here, we evaluate how decompression and venting affect stress and mortality in the Yellow Tang (Zebrasoma flavescens). We examined the effects of three ascent treatments, each with decompression stops of varying frequency and duration, coupled with or without venting, on sublethal effects and mortality using histology and serum cortisol measurements. In fish subjected to ascent without decompression stops or venting, a mean post-collection mortality of 6.2% occurred within 24 h of capture. Common collection methods in the fishery, ascent without decompression stops coupled with venting, or one long decompression stop coupled with venting, resulted in no mortality. Histopathologic examination of heart, liver, head kidney, and swim bladder tissues in fish 0d and 21d post-collection revealed no significant barotrauma- or venting-related lesions in any treatment group. Ascent without decompression stops resulted in significantly higher serum cortisol than ascent with many stops, while venting alone did not affect cortisol. Future work should examine links in the supply chain following collection to determine if further handling and transport stressors affect survivorship and sublethal effects.

A comparison of microscopic ink characteristics of 35 commercially available surgical margin inks.

OBJECTIVE: To compare microscopic characteristics of commercially available surgical margin inks used for surgical pathology specimens. STUDY DESIGN: Prospective in vitro study. SAMPLE POPULATION: Thirty-five different surgical margin inks (black, blue, green, orange, red, violet, and yellow from 5 different manufacturers). METHODS: Inks were applied to uniform, single-source, canine cadaveric full-thickness ventral abdominal tissue blocks. Tissue blocks and ink manufacturers were randomly paired and each color was applied to a length of the cut tissue margin. After drying, tissues were fixed in formalin, and 3 radial slices were obtained from each color section and processed for routine histologic evaluation, yielding 105 randomly numbered slides with each manufacturer's color represented in triplicate. Slides were evaluated by 5 blinded, board-certified veterinary anatomic pathologists using a standardized scoring scheme. Statistical analyses were performed to evaluate for ink manufacturer effects on scores, correlation among different subjective variables, and pathologist agreement. RESULTS: Black and blue had the most consistently high scores whereas red and violet had the most consistently low overall scores, across all manufacturers. All colors tested, except yellow, had statistically significant differences in overall scores among individual manufacturers. Overall score was significantly correlated to all other subjective microscopic scores evaluated. The average Spearman correlation coefficient among the 10 pairwise pathologists overall ink scores was 0.60. CONCLUSIONS: There are statistically significant differences in microscopic ink characteristics among manufacturers, with a notable degree of inter-pathologist agreement.

Anti-glucagon-like peptide-1 immunoreactivity in samples of blood and ileum obtained from neonatal and adult alpacas.

OBJECTIVE: To compare numbers of L cells in intestinal samples and blood concentrations of glucagon-like peptide (GLP)-1 between neonatal and mature alpacas. SAMPLE: Intestinal samples from carcasses of 4 suckling crias and 4 postweaning alpacas for immunohistochemical analysis and blood samples from 32 suckling crias and 19 healthy adult alpacas for an ELISA. PROCEDURES: Immunohistochemical staining was conducted in accordance with Oregon State University Veterinary Diagnostic Laboratory standard procedures with a rabbit polyclonal anti-GLP-1 primary antibody. Stained cells with staining results in ileal tissue were counted in 20 fields by 2 investigators, and the mean value was calculated. For quantification of GLP-1 concentrations, blood samples were collected into tubes containing a dipeptidyl peptidase-4 inhibitor. Plasma samples were tested in duplicate with a commercial GLP-1 ELISA validated for use in alpacas. RESULTS: Counts of stained cells (mean ± SD, 50 ± 18 cells) and plasma GLP-1 concentrations (median, 0.086 ng/mL; interquartile range, 0.061 to 0.144 ng/mL) were higher for suckling alpacas than for postsuckling alpacas (stained cells, 26 ± 4 cells; plasma GLP-1 concentration, median, 0.034 ng/mL; interquartile range, 0.015 to 0.048 ng/mL). CONCLUSIONS AND CLINICAL RELEVANCE: Older alpacas had lower numbers of L cells in intestinal tissues and lower blood concentrations of GLP-1 than those in neonates. These findings suggested that there may be a decrease in the contribution of GLP-1 to insulin production in adult alpacas, compared with the contribution in neonates.

Analysis of koi herpesvirus latency in wild common carp and ornamental koi in Oregon, USA.

Koi herpesvirus (KHV) infection is associated with high mortalities in both common carp (Cyprinus carpio carpio) and koi carp (Cyprinus carpio koi) worldwide. Although acute infection has been reported in both domestic and wild common carp, the status of KHV latent infection is largely unknown in wild common carp. To investigate whether KHV latency is present in wild common carp, the distribution of KHV latent infection was investigated in two geographically distinct populations of wild common carp in Oregon, as well as in koi from an Oregon-based commercial supplier. Latent KHV infection was demonstrated in white blood cells from each of these populations. Although KHV isolated from acute infections has two distinct genetic groups, Asian and European, KHV detected in wild carp has not been genetically characterized. DNA sequences from ORF 25 to 26 that are unique between Asian and European were investigated in this study. KHV from captive koi and some wild common carp were found to have ORF-25-26 sequences similar to KHV-J (Asian), while the majority of KHV DNA detected in wild common carp has similarity to KHV-U/-I (European). In addition, DNA sequences from IL-10, and TNFR were sequenced and compared with no differences found, which suggests immune suppressor genes of KHV are conserved between KHV in wild common carp and koi, and is consistent with KHV-U, -I, -J.

Pulmonary arteriovenous malformation in two adult alpacas (Vicugna pacos).

Two cases of pulmonary vascular anomaly in unrelated adult alpacas (Vicugna pacos) are described. In the first case, a 9-year-old intact male alpaca presented at Oregon State University Veterinary Teaching Hospital with bilateral epistaxis and died the subsequent day following severe hemorrhage from the mouth and nostrils. At necropsy, a tortuous vascular lesion was identified in the right cranial lung lobe, associated with hemorrhage into airways. In the second case, a 2-year-old female alpaca presented with postpartum anorexia, opisthotonus, and recumbency. In this second case, a similar vascular lesion was identified in the right cranial lung lobe but without associated hemorrhage. Histopathological examination of the lesion in both cases revealed numerous dilated, irregular blood vessels with marked variation in wall thickness within vessels, surrounded by foci of extramedullary hematopoiesis. Diagnoses of locally extensive pulmonary vascular anomalies (arteriovenous malformations) were made.

Investigation of koi herpesvirus latency in koi.

Koi herpesvirus (KHV) has recently been classified as a member of the family of Alloherpesviridae within the order of Herpesvirales. One of the unique features of Herpesviridae is latent infection following a primary infection. However, KHV latency has not been recognized. To determine if latency occurs in clinically normal fish from facilities with a history of KHV infection or exposure, the presence of the KHV genome was investigated in healthy koi by PCR and Southern blotting. KHV DNA, but not infectious virus or mRNAs from lytic infection, was detected in white blood cells from investigated koi. Virus shedding was examined via tissue culture and reverse transcription-PCR (RT-PCR) testing of gill mucus and feces from six koi every other day for 1 month. No infectious virus or KHV DNA was detected in fecal secretion or gill swabs, suggesting that neither acute nor persistent infection was present. To determine if KHV latent infections can be reactivated, six koi were subjected to a temperature stress regime. KHV DNA and infectious virus were detected in both gill and fecal swabs by day 8 following temperature stress. KHV DNA was also detectable in brain, spleen, gills, heart, eye, intestine, kidney, liver, and pancreas in euthanized koi 1 month post-temperature stress. Our study suggests that KHV may become latent in leukocytes and other tissues, that it can be reactivated from latency by temperature stress, and that it may be more widespread in the koi population than previously suspected.

Knockdown of bicaudal C in zebrafish (Danio rerio) causes cystic kidneys: a nonmammalian model of polycystic kidney disease.

Polycystic kidney disease (PKD) is one of the leading causes of end-stage renal disease in humans and is characterized by progressive cyst formation, renal enlargement, and abnormal tubular development. Currently, there is no cure for PKD. Although a number of PKD genes have been identified, their precise role in cystogenesis remains unclear. In the jcpk mouse model of PKD, mutations in the bicaudal C gene (Bicc1) are responsible for the cystic phenotype; however, the function of Bicc1 is unknown. In this study, we establish an alternative, nonmammalian zebrafish model to study the role of Bicc1 in PKD pathogenesis. Antisense morpholinos were used to evaluate loss of Bicc1 function in zebrafish. The resulting morphants were examined histologically for kidney cysts and structural abnormalities. Immunostaining and fluorescent dye injection were used to evaluate pronephric cilia and kidney morphogenesis. Knockdown of zebrafish Bicc1 expression resulted in the formation of kidney cysts; however, defects in kidney structure or pronephric cilia were not observed. Importantly, expression of mouse Bicc1 rescues the cystic phenotype of the morphants. These results demonstrate that the function of Bicc1 in the kidney is evolutionarily conserved, thus supporting the use of zebrafish as an alternative in vivo model to study the role of mammalian Bicc1 in renal cyst formation.

Gastric smooth muscle hamartoma in a cat.

An 11-year-old cat presented for evaluation of intermittent vomiting, constipation and hyporexia of 3 weeks duration. Ultrasonographic and endoscopic examination revealed a soft tissue mass adjacent to the lower gastro-esophageal sphincter. Surgical excision of the mass was successfully performed resulting in a resolution of clinical signs. Histologically the mass was consistent with a smooth muscle hamartoma. At follow-up 7 months after surgery, the cat remained free from clinical signs.

Eimeria macusaniensis infection in 15 llamas and 34 alpacas.

CASE DESCRIPTION: 15 llamas and 34 alpacas between 3 weeks and 18 years old with fecal oocysts or intestinal coccidial stages morphologically consistent with Eimeria macusaniensis were examined. Nineteen of the camelids were admitted dead, and 30 were admitted alive. Camelids admitted alive accounted for 5.5% of all camelid admissions during this period. CLINICAL FINDINGS: Many severely affected camelids had signs of lethargy, weight loss, decreased appetite, and diarrhea. Camelids with clinical infection also commonly had evidence of circulatory shock, fat mobilization, and protein loss. Nonsurviving camelids also had evidence of shock, edema, bile stasis, renal insufficiency, hepatic lipidosis, muscle damage, relative hemoconcentration, and sepsis. Postmortem examination frequently revealed complete, segmental replacement of the mucosa of the distal portion of the jejunum with coccidial meronts and gamonts. For 17 of 42 camelids, results of initial fecal examinations for E macusaniensis were negative. TREATMENT AND OUTCOME: Most camelids admitted alive were treated with amprolium hydrochloride, plasma, and various supportive treatments. Fifteen of the 30 treated camelids died or were euthanized. CLINICAL RELEVANCE: Findings suggest that E macusaniensis may be an important gastrointestinal tract pathogen in camelids of all ages. Clinical signs were frequently nonspecific and were often evident before results of fecal examinations for the parasite were positive. As with other coccidia, severity of disease was probably related to ingested dose, host immunity, and other factors. The clinical and herd relevance of positive fecal examination results must be determined.

Encrusted cystitis secondary to Corynebacterium matruchotii infection in a horse.

A 17-year-old gelding was evaluated because of dysuria, inappetence, and weight loss. Cystoscopy revealed severe mucosal ecchymoses with luminal hemorrhage and accumulations of crystalloid sludge. Analysis of a urine sample revealed isosthenuria, an alkaline pH, pyuria, hematuria, bacteriuria, and numerous calcium carbonate crystals. Histologic examination of bladder mucosa biopsy specimens revealed severe neutrophilic infiltration with mineralization. A diagnosis of encrusted cystitis exacerbated by sabulous urolithiasis was made. A Corynebacterium sp susceptible to penicillin, sulfonamide, and enrofloxacin was cultured from the urine and the bladder mucosa biopsy specimens. The horse was treated with penicillin G potassium, IV, for 5 days, followed by trimethoprim-sulfamethoxazole for 4 weeks. Bladder lavage was performed daily for the first 3 days with a balanced electrolyte solution and dimethyl sulfoxide in an attempt to aid expulsion of necrotic debris and crystalline sludge from the bladder. Molecular phylogenetic analysis based on the 16S rDNA gene sequence was used to identify the isolate and determine its phylogenetic position. Results indicated that the isolate was closely related to Corynebacterium matruchotii. To our knowledge, encrusted cystitis secondary to C matruchotii has not been previously identified in a horse.

Keratinizing ameloblastoma in a 9-month-old llama (Lama glama).

A 9-month-old male llama (Lama glama) was presented because of a rapidly growing mass on the right side of the face. Radiographs revealed a marked expansion of the right caudal face region with bone lysis involving the maxilla and the nasal, lacrimal, zygomatic, and palatine bones. Cytologically, the mass consisted of atypical round to polygonal cells with round nuclei and basophilic cytoplasms that formed acini and rows. Histologically, the mass consisted of anastomosing cords and sheets of neoplastic odontogenic epithelial cells embedded in a loose fibrovascular connective tissue. Single layers of peripheral, polarized, palisading, columnar epithelial cells were seen at the edges of some cords. Within the centers of the cords, epithelial cells showed rapid progression to keratin production. The histologic diagnosis was keratinizing ameloblastoma. Ameloblastomas are neoplasms of odontogenic epithelium that tend to be locally aggressive and can cause substantial destruction of bony structures. Because ameloblastomas do not tend to metastasize, they can be successfully treated by complete surgical excision, performed before extensive bony destruction occurs. Ameloblastoma, although expected to be rare, should be onthe list of differential diagnoses for facial swelling in llamas.

The relationship between endogenous cortisol, blood micronutrients, and neutrophil function in postparturient Holstein cows.

Neutrophil function, blood micronutrients, and cortisol concentrations were measured in 43 clinically healthy postparturient Holstein cows. Estimated 305-day mature equivalent milk production and neutrophil function were related to results of the blood micronutrient concentrations and neutrophil function tests. Cattle had low to normal zinc concentrations; normal to high selenium, vitamin E, and cortisol concentrations; and normal copper concentrations. Blood selenium (P = .03) and zinc (P = .027) concentrations were both significant predictors of neutrophil adhesion, and selenium (P < .001) was a significant predictor of neutrophil cytochrome C reduction (superoxide production). Fourteen of 20 (70%) cattle with blood selenium concentrations > 300 ng/mL had neutrophil adhesion, and 15 of 20 (75%) had cytochrome C reduction above the mean value for this group. There was also a significant correlation (r = 0.331; P = .037) between cytochrome C reduction and estimated milk production. These findings suggest that neutrophils from postparturient dairy cows with higher blood concentrations of selenium have greater potential to kill microbes, and that cattle with greater superoxide production may have higher milk production.

Bile acids in gastric fluids from llamas and alpacas with and without ulcers.

To investigate the relationship between duodenogastric reflux and ulceration, gastric fluid was collected from the 1st (n = 26) and 3rd (n = 45) gastric compartments of llamas and alpacas during postmortem examination. Gastric fluids were analyzed for the presence of bile acids. Additionally, the 3rd compartment was examined grossly for the presence of erosions or ulcers, and the intestines were examined for evidence of fluid distention. Detectable bile acids were found in the 3rd compartment fluid of 1 of 28 camelids without ulcers, 7 of 14 camelids with ulcers, and 3 of 3 camelids with intestinal distention. Third compartment bile content was significantly higher in camelids with ulcers (median = 2.9 micromol/L) or intestinal distention (median = 371.5 micromol/L) than those with neither (median = 0 micromol/L). Bile acids were detected in the 1st gastric compartment in only 2 camelids. These findings suggest a reflux of duodenal contents, including bile acids, into the 3rd compartment in camelids with ulcers, similar to what is seen in camelids with poor intestinal emptying. Whether bile reflux was the cause of the ulcers or occurred after or concurrent to their development remains unknown.

Visceral nodular cartilaginous metaplasia in rockfishes (Sebastes spp.) in the eastern North Pacific Ocean.

Multiple, discrete, nodular foci of cartilaginous metaplasia were found in the spleens and kidneys of rockfishes taken from the northeastern Pacific Ocean during a survey to determine the incidence and the nature of diseases in these animals. These nodules sometimes occurred in association with granulomatous inflammation and distinct granulomas. Many of these fish were infected by Ichythophonus spp. or acid-fact bacteria (presumably Mycobacteria spp.). Some of the metaplastic foci contained encapsulated accumulations of eosinophilic vesicles and basophilic granular debris, described by other authors as "cysts of unknown etiology," which have been observed at different sites in a variety of temperate and tropical fish species.