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Introduction. Helicobacter suis ( Helicobacter heilmannii type 1) commonly infects nonhuman primates but its clinical importance is in question. Aim. To characterize H. suis infection in a colony of rhesus macaques ( Macaca mulatta ) used in cognitive neuroscience research. Hypothesis/Gap Statement. Inquiries into the nature of Helicobacter suis in nonhuman primates are required to further define the organism's virulence and the experimental animal's gastric microbiome. Methodology. Animals with and without clinical signs of vomiting and abdominal pain ( n =5 and n =16, respectively) were evaluated by histology, culture, PCR amplification and sequencing, fluorescent in situ hybridization (FISH) and serology. Three of the five animals with clinical signs, an index case and two others, were evaluated before and after antimicrobial therapy. Results. The index animal had endoscopically visible ulcers and multifocal, moderate, chronic lymphoplasmacytic gastritis with intraglandular and luminal spiral bacteria. Antimicrobial therapy in the index animal achieved histologic improvement, elimination of endoscopically visible ulcers, and evident eradication but clinical signs persisted. In the other treated animals, gastritis scores were not consistently altered, gastric bacteria persisted, but vomiting and abdominal discomfort abated.Nineteen of 21 animals were PCR positive for H. suis and five animals were also PCR positive for H. pylori . Organisms were detected by FISH in 17 of 21 animals: 16S rRNA sequences of two of these were shown to be H. suis . Mild to moderate lymphoplasmacytic gastritis was seen in antrum, body and cardia, with antral gastritis more likely to be moderate than that of the body. Conclusion. No clear association between the bacterial numbers of Helicobacter spp. and the degree of inflammation was observed. H. suis is prevalent in this colony of Macaca mulatta but its clinical importance remains unclear. This study corroborates many of the findings in earlier studies of H. suis infection in macaques but also identifies at least one animal in which gastritis and endoscopically visible gastric ulcers were strongly associated with H. suis infection. In this study, serology was an inadequate biomarker for endoscopic evaluation in diagnosis of H. suis infection.

Premise: While root-order approaches to fine-root classification have shown wide utility among wild plants, they have seen limited use for perennial crop plants. Moreover, inadequate characterization of fine roots across species of domesticated perennial crops has led to a knowledge gap in the understanding of evolutionary and functional patterns associated with different fine-root orders., Methods: We examined fine-root traits of common horticultural fruit and nut crops: Malus ×domestica, Prunus persica, Vitus vinifera, Prunus dulcis, and Citrus ×clementina. Additional roots were sampled from 33 common perennial horticultural crops, native to tropical, subtropical, and temperate regions, to examine variation in 1st- and 2nd-order absorptive roots., Results: First-order roots of grape and 1st- and 2nd-order roots of apple and peach were consistently thin, nonwoody, mycorrhizal, and had high N:C ratios. In contrast, 4th- and 5th-order roots of grape and 5th-order roots of apple and peach were woody, nonmycorrhizal, had low N:C ratios, and were thicker than lower-order roots. Among the 33 horticultural species, diameter of 1st- and 2nd-order roots varied about 15-fold, ranging from 0.04 to 0.60 mm and 0.05 to 0.89 mm respectively. This variation generally was phylogenetically conserved across plant lineages., Conclusions: Collectively, our research shows that root-order characterization has considerably more utility than an arbitrary diameter cutoff for identifying roots of different functions in perennial horticultural crops. In addition, much of the variation in root diameter among species can be predicted by evolutionary relationships., (© 2020 Botanical Society of America.)

We have developed a system that could potentially be used to identify the site of origin of ventricular tachycardia (VT) and to guide a catheter to that site to deliver radio-frequency ablation therapy. This system employs the Inverse Solution Guidance Algorithm based upon Single Equivalent Moving Dipole (SEMD) localization method. The system was evaluated in in vivo swine experiments. Arrays consisting of 9 or 16 bipolar epicardial electrodes and an additional mid-myocardial pacing lead were sutured to each ventricle. Focal tachycardia was simulated by applying pacing pulses to each epicardial electrode at multiple pacing rates during breath hold at the end-expiration phase. Surface potentials were recorded from 64 surface electrodes and then analyzed using the SEMD method to localize the position of the pacing electrodes. We found a close correlation between the locations of the pacing electrodes as measured in computational and real spaces. The reproducibility error of the SEMD estimation of electrode location was 0.21 ± 0.07 cm. The vectors between every pair of bipolar electrodes were computed in computational and real spaces. At 120 bpm, the lengths of the vectors in the computational and real space had a 95% correlation. Computational space vectors were used in catheter guidance simulations which showed that this method could reduce the distance between the real space locations of the emulated catheter tip and the emulated arrhythmia origin site by approximately 72% with each movement. We have demonstrated the feasibility of using our system to guide a catheter to the site of the emulated VT origin.

The sesquiterpenoid rotundone is the compound responsible for the "black pepper" aroma of many plant species, including several economically important wine grape varieties. Since its identification in wine in 2008, there has been an increased interest in understanding how individual climatic or cultural factors affect the accumulation of rotundone in grapes and subsequently the level of wine "pepperiness." However, no study has assessed climatic and viticultural factors together to identify which variables have the strongest influence on rotundone accumulation. Our study aimed to fill this knowledge gap by developing a predictive model that identified factors that explain rotundone concentrations in Noiret ( Vitis sp.) grapes at harvest. Over the 2016 and 2017 seasons, we measured 21 viticultural, meso- and microclimatic variables and concentrations of rotundone in Noiret wine grapes at seven vineyards in the northeastern U.S. Vineyard growing degree days (GDD v ) and the amount of solar radiation (cumulative solar exposure; CSE v ) accumulated from the beginning of fruit ripening to harvest were the variables best correlated ( r = 0.70 and r = 0.74, respectively) with rotundone concentrations. Linear correlations between microclimatic parameters and rotundone concentrations were weaker, but overall rotundone was negatively correlated with low (<15°C) and high (>30°C) berry temperatures. Using the 2-year data set we were able to develop a four-variable model which explained more than 80% of the variation in rotundone concentration at harvest. The model included weather [growing degree days during fruit ripening (GDD v )] and plant-related variables (concentrations of phosphorus and calcium in the leaf petiole, and crop load). The model we developed could be used by wine producers to identify sites or cultural practices that favor rotundone accumulation in Noiret grapes after performing a model validation with an additional, external data set. More broadly, the statistical approach used here could be applied to other studies that also seek to assess the effects of multiple factors on a variable of interest under varying environmental conditions., (Copyright © 2019 Harner, Vanden Heuvel, Marini, Elias and Centinari.)

Intravenous regional anesthesia (IVRA; Bier block) is commonly used to anesthetize an extremity for surgery. Limitations of the procedure include pain from the required tourniquet, the toxicity that can occur from systemic release of local anesthetics, and the lack of postoperative pain relief. We hypothesized that the nanoencapsulation of the local anesthetic would prolong local anesthesia and enhance safety. Here, we developed an ∼15 nm micellar bupivacaine formulation (M-Bup) and tested it in a rat tail vein IVRA model, in which active agents were restricted in the tail by a tourniquet for 15 min. After tourniquet removal, M-Bup provided local anesthesia for 4.5 h, which was two times longer than that from a larger dose of free bupivacaine. Approximately 100 nm liposomal bupivacaine (L-Bup) with the same drug dose as M-Bup did not cause anesthesia. Blood levels of bupivacaine after tourniquet removal were lower in animals receiving M-Bup than L-Bup or free bupivacaine, demonstrating enhanced safety. Tissue reaction to M-Bup was benign.

Non-human primates (NHPs) for biomedical research are commonly infected with Shigella spp. that can cause acute dysentery or chronic episodic diarrhea. These animals are often prophylactically and clinically treated with quinolone antibiotics to eradicate these possible infections. However, chromosomally- and plasmid-mediated antibiotic resistance has become an emerging concern for species in the family Enterobacteriaceae . In this study, five individual isolates of multi-drug resistant Shigella flexneri were isolated from the feces of three macaques. Antibiotic susceptibility testing confirmed resistance or decreased susceptibility to ampicillin, amoxicillin-clavulanic acid, cephalosporins, gentamicin, tetracycline, ciprofloxacin, enrofloxacin, levofloxacin, and nalidixic acid. S. flexneri isolates were susceptible to trimethoprim-sulfamethoxazole, and this drug was used to eradicate infection in two of the macaques. Plasmid DNA from all isolates was positive for the plasmid-encoded quinolone resistance gene qnrS , but not qnrA and qnrB . Conjugation and transformation of plasmid DNA from several S. flexneri isolates into antibiotic-susceptible Escherichia coli strains conferred the recipients with resistance or decreased susceptibility to quinolones and beta-lactams. Genome sequencing of two representative S. flexneri isolates identified the qnrS gene on a plasmid-like contig. These contigs showed >99% homology to plasmid sequences previously characterized from quinolone-resistant Shigella flexneri 2a and Salmonella enterica strains. Other antibiotic resistance genes and virulence factor genes were also identified in chromosome and plasmid sequences in these genomes. The findings from this study indicate macaques harbor pathogenic S. flexneri strains with chromosomally- and plasmid-encoded antibiotic resistance genes. To our knowledge, this is the first report of plasmid-mediated quinolone resistance in S. flexneri isolated from NHPs and warrants isolation and antibiotic testing of enteric pathogens before treating macaques with quinolones prophylactically or therapeutically.

Background: Many Escherichia coli strains are considered to be a component of the normal flora found in the human and animal intestinal tracts. While most E. coli strains are commensal, some strains encode virulence factors that enable the bacteria to cause intestinal and extra-intestinal clinically-relevant infections. Colibactin, encoded by a genomic island ( pks island), and cytotoxic necrotizing factor (CNF), encoded by the cnf gene, are genotoxic and can modulate cellular differentiation, apoptosis and proliferation. Some commensal and pathogenic pks + and cnf + E. coli strains have been associated with inflammation and cancer in humans and animals., Results: In the present study, E. coli strains encoding colibactin and CNF were identified in macaque samples. We performed bacterial cultures utilizing rectal swabs and extra-intestinal samples from clinically normal macaques. A total of 239 E. coli strains were isolated from 266 macaques. The strains were identified biochemically and selected isolates were serotyped as O88:H4, O25:H4, O7:H7, OM:H14, and OM:H16. Specific PCR for pks and cnf1 gene amplification, and phylogenetic group identification were performed on all E. coli strains. Among the 239 isolates, 41 (17.2%) were pks + /cnf1 -, 19 (7.9%) were pks -/ cnf1 +, and 31 (13.0%) were pks +/ cnf1 +. One hundred forty-eight (61.9%) E. coli isolates were negative for both genes ( pks -/ cnf1 -). In total, 72 (30.1%) were positive for pks genes, and 50 (20.9%) were positive for cnf1 . No cnf2 + isolates were detected. Both pks + and cnf1 + E. coli strains belonged mainly to phylogenetic group B2, including B2 1 . Colibactin and CNF cytotoxic activities were observed using a HeLa cell cytotoxicity assay in representative isolates. Whole genome sequencing of 10 representative E. coli strains confirmed the presence of virulence factors and antibiotic resistance genes in rhesus macaque E. coli isolates., Conclusions: Our findings indicate that colibactin- and CNF-encoding E. coli colonize laboratory macaques and can potentially cause clinical and subclinical diseases that impact macaque models.

Metal alloys are frequently used as implant materials in veterinary medicine. Recent studies suggest that many alloys induce both local and systemic inflammatory responses. In this study, 37 rhesus macaques with long-term skull-anchored percutaneous titanium alloy implants (duration, 0 to 14 y) were evaluated for changes in their hematology, coagulation, and serum chemistry profiles. Negative controls (n = 28) did not have implants. Macaques with implants had higher plasma D-dimer and lower antithrombin III concentrations than nonimplanted animals. In addition, animals with implants had higher globulin and lower albumin and calcium concentrations compared with nonimplanted macaques. Many of these changes were positively correlated with duration of implantation and the number of implants. Chronic bacterial infection of the skin was present around many of the implant sites and within deeper tissues. Representative histopathology around the implant site of 2 macaques revealed chronic suppurative to pyogranulomatous inflammation extending from the skin to the dura mater. X-ray fluorescence microscopy of tissue biopsies from the implant site of the same 2 animals revealed significantly higher levels of free metal ions in the tissue, including titanium and iron. The higher levels of free metal ions persisted in the tissues for as long as 6 mo after explantation. These results suggest that long-term skull-anchored percutaneous titanium alloy implants can be associated with localized inflammation, chronic infection, and leaching of metal ions into local tissues.

Ferrets have become more popular as household pets and as animal models in biomedical research in the past 2 decades. The average life span of ferrets is about 5-11 years with onset of geriatric diseases between 3-4 years including endocrinopathies, neoplasia, gastrointestinal diseases, cardiomyopathy, splenomegaly, renal diseases, dental diseases, and cataract. Endocrinopathies are the most common noninfectious disease affecting middle-aged and older ferrets. Spontaneous neoplasms affecting the endocrine system of ferrets appear to be increasing in prevalence with a preponderance toward proliferative lesions in the adrenal cortex and pancreatic islet cells. Diet, gonadectomy, and genetics may predispose ferrets to an increased incidence of these endocrinopathies. These functional proliferative lesions cause hypersecretion of hormones that alter the physiology and metabolism of the affected ferrets resulting in a wide range of clinical manifestations. However, there is an apparent dearth of information available in the literature about the causal relationship between aging and neoplasia in ferrets. This review provides a comprehensive overview of the anatomy and physiology of endocrine organs, disease incidence, age at diagnosis, clinical signs, pathology, and molecular markers available for diagnosis of various endocrine disorders in ferrets., (© The Author(s) 2016.)

A mature female squirrel monkey was noted during routine semiannual examinations to have moderate progressive weight loss. Serum chemistry panels revealed marked increases in hepatic enzyme, bilirubin, and bile salt concentrations and hypoalbuminemia. Abdominal ultrasonography revealed echogenic, shadowing debris in the gallbladder, consistent with cholelithiasis. At necropsy, marked thickening and distension of the gallbladder, cystic duct, and common bile duct was noted, and more than 50 irregularly shaped, black gallstones were removed from the biliary tract. Gallbladder tissue, bile, and gallstones cultured positive for Escherichia coli and Proteus spp., suggesting a brown-pigment gallstone type secondary to a bacterial nidus. Histopathology revealed severe chronic-active diffuse cholecystitis and severe chronic-active hepatic degeneration and necrosis with severe cholestasis. To our knowledge, this report is the first description of spontaneous choleilthiasis in a squirrel monkey.

Rhesus macaques (Macaca mulatta) are a common model for the study of human biology and disease. To manage coagulopathies in these animals and to study their clotting changes, the ability to measure coagulation biomarkers is necessary. Currently, few options for coagulation testing in NHP are commercially available. In this study, assays for 4 coagulation biomarkers-D-dimer, antithrombin III, protein C, and soluble P-selectin-were developed and optimized for rhesus macaques. Whole blood was collected from 28 healthy Chinese-origin rhesus macaques (11 male; 17 female) ranging in age from 5 to 20 y. Coagulation biomarkers were measured by using bead-based sandwich ELISA technology. The ranges (mean ± 90% confidence interval) for these biomarkers were: antithrombin III, 124.2 to 133.4 μg/mL; protein C, 3.2 to 3.6 μg/mL; D-dimer, 110.3 to 161.3 ng/mL; soluble P-selectin, 0.12 to 0.14 ng/10(6) platelets. These reference values did not differ significantly according to sex or age. These new assays for coagulation biomarkers in rhesus macaques will facilitate the evaluation of in vivo hemostasis.

Background: We developed and evaluated a novel system for guiding radiofrequency catheter ablation therapy of ventricular tachycardia. This guidance system employs an inverse solution guidance algorithm (ISGA) using a single equivalent moving dipole (SEMD) localization method. The method and system were evaluated in both a saline tank phantom model and in vivo animal (swine) experiments., Methods: A catheter with two platinum electrodes spaced 3 mm apart was used as the dipole source in the phantom study. A 40-Hz sinusoidal signal was applied to the electrode pair. In the animal study, four to eight electrodes were sutured onto the right ventricle. These electrodes were connected to a stimulus generator delivering 1-ms duration pacing pulses. Signals were recorded from 64 electrodes, located either on the inner surface of the saline tank or on the body surface of the pig, and then processed by the ISGA to localize the physical or bioelectrical SEMD., Results: In the phantom studies, the guidance algorithm was used to advance a catheter tip to the location of the source dipole. The distance from the final position of the catheter tip to the position of the target dipole was 2.22 ± 0.78 mm in real space and 1.38 ± 0.78 mm in image space (computational space). The ISGA successfully tracked the locations of electrodes sutured on the ventricular myocardium and the movement of an endocardial catheter placed in the animal's right ventricle., Conclusion: In conclusion, we successfully demonstrated the feasibility of using an SEMD inverse algorithm to guide a cardiac ablation catheter., (©2013, The Authors. Journal compilation ©2013 Wiley Periodicals, Inc.)

Obtaining an animal's body temperature is essential for the assessment of its clinical status. For many species, rectal thermometry is the technique used most often; however, this method in macaques typically requires sedation or considerable physical restraint. A noninvasive and inexpensive temporal artery (TA) thermometer was evaluated as an alternative method for collecting body temperature measurements from macaques used in neuroscience research. Rectal and arterial temperatures were obtained from 86 macaques (mean age, 10.2 y) that had received ketamine (10 mg/kg IM) or Telazol (5 mg/kg IM); the arterial measurements were taken from behind the right ear. In addition, arterial temperatures were measured behind both ears in a cohort of awake, chaired macaques with cephalic restraint pedestals only (n = 8) or with cephalic restraint pedestals and recording chambers (n = 14). Within-subject repeatability for TA thermometry and agreement between rectal and arterial temperature measurements were assessed by using the Bland-Altman method. Temperature measurements indicated that values from TA thermometry were lower than those from rectal thermometry by 1.57 °C with a 95% agreement limit of ± 1.27 °C. Results show satisfactory repeatability with TA thermometry and agreement between arterial and rectal temperatures, demonstrating that TA thermometry can be a valuable tool in conscious, chaired macaques with restrained heads.

Bacteria of the genus Corynebacterium are important primary and opportunistic pathogens. Many are zoonotic agents. In this report, phenotypic (API Coryne analysis), genetic (rpoB and 16S rRNA gene sequencing), and physical methods (MS) were used to distinguish the closely related diphtheroid species Corynebacterium ulcerans and Corynebacterium pseudotuberculosis, and to definitively diagnose Corynebacterium renale from cephalic implants of rhesus (Macaca mulatta) and cynomolgus (Macaca fascicularis) macaques used in cognitive neuroscience research. Throat and cephalic implant cultures yielded 85 isolates from 43 macaques. Identification by API Coryne yielded C. ulcerans (n = 74), Corynebacterium pseudotuberculosis (n = 2), C. renale or most closely related to C. renale (n = 3), and commensals and opportunists (n = 6). The two isolates identified as C. pseudotuberculosis by API Coryne required genetic and MS analysis for accurate characterization as C. ulcerans. Of three isolates identified as C. renale by 16S rRNA gene sequencing, only one could be confirmed as such by API Coryne, rpoB gene sequencing and MS. This study emphasizes the importance of adjunct methods in identification of coryneforms and is the first isolation of C. renale from cephalic implants in macaques.

The purpose of this study was to introduce and validate a new algorithm to estimate instantaneous aortic blood flow (ABF) by mathematical analysis of arterial blood pressure (ABP) waveforms. The algorithm is based on an autoregressive with exogenous input (ARX) model. We applied this algorithm to diastolic ABP waveforms to estimate the autoregressive model coefficients by requiring the estimated diastolic flow to be zero. The algorithm incorporating the coefficients was then applied to the entire ABP signal to estimate ABF. The algorithm was applied to six Yorkshire swine data sets over a wide range of physiological conditions for validation. Quantitative measures of waveform shape (standard deviation, skewness, and kurtosis), as well as stroke volume and cardiac output from the estimated ABF, were computed. Values of these measures were compared with those obtained from ABF waveforms recorded using a Transonic aortic flow probe placed around the aortic root. The estimation errors were compared with those obtained using a windkessel model. The ARX model algorithm achieved significantly lower errors in the waveform measures, stroke volume, and cardiac output than those obtained using the windkessel model (P < 0.05).

A cohort of rhesus macaques used in neuroscience research was found at routine examinations to have chronic anemia (spun Hct less than 30%). Four anemic (Hct, 24.8% ± 3.4%) and 10 control (39.6% ± 2.9%) macaques were assessed to characterize the anemia and determine probable cause(s); some animals in both groups had cephalic implants. Diagnostic tests included CBC, bone marrow evaluations, iron panels, and serum erythropoietin and hepcidin concentrations. Serum iron and ferritin were 15.8 ± 11.1 μg/dL and 103.8 ± 53.1 ng/mL, respectively, for the anemic group compared with 109.8 ± 23.8 μL/dL and 88.5 ± 41.9 ng/mL, respectively, for the control group. Erythropoietin levels were 16.2 to over 100 mU/mL for the anemic macaques compared with 0 to 1.3 mU/mL for the control group. Hepcidin results were similar in both groups. Because the findings of low iron, high erythropoietin, and normal hepcidin in the anemic macaques supported iron-deficiency anemia or anemia of chronic disease combined with iron-deficiency anemia, a regimen of 4 doses of iron dextran was provided. In treated macaques, Hct rose to 36.3% ± 6.8%, serum iron levels increased to 94.0 ± 41.9 μg/dL, and erythropoietin levels fell to 0.15 to 0.55 mU/mL. Maintenance of normal Hct was variable between macaques and reflected individual ongoing clinical events.

Helicobacter pylori-associated gastric cancer is male predominant and animal studies suggest that sex hormones influence gastric carcinogenesis. We investigated the effects of 17β-estradiol (E2) or castration on H.pylori-induced gastritis in male INS-GAS/FVB/N (Tg(Ins1-GAS)1Sbr) mice. Comparisons were made to previously evaluated sham (n = 8) and H.pylori-infected (n = 8), intact male INS-GAS mice which had developed severe corpus gastritis accompanied by atrophy, hyperplasia, intestinal metaplasia and dysplasia of the epithelium within 16 weeks postinfection (all P < 0.01). Castration at 8 weeks of age had no sparing effect on lesions in uninfected (n = 5) or H.pylori-infected mice (n = 7) but all lesion subfeatures were attenuated by E2 in H.pylori-infected mice (n = 7) (P < 0.001). Notably, inflammation was not reduced but glandular atrophy, hyperplasia, intestinal metaplasia and dysplasia were also less severe in uninfected, E2-treated mice (n = 7) (P < 0.01). Attenuation of gastric lesions by E2 was associated with lower messenger RNA (mRNA) expression of interferon (IFN)-γ (P < 0.05) and interleukin (IL)-1β (P < 0.004), and higher IL-10 (P < 0.02) as well as decreased numbers of Foxp3(+) regulatory T cells when compared with infected intact males. Infected E2-treated mice also developed higher Th2-associated anti-H.pylori IgG1 responses (P < 0.05) and significantly lower Ki-67 indices of epithelial proliferation (P < 0.05). E2 elevated expression of mRNA for Foxp3 (P < 0.0001) and IL-10 (P < 0.01), and decreased IL-1β (P < 0.01) in uninfected, intact male mice compared with controls. Therefore, estrogen supplementation, but not castration, attenuated gastric lesions in H.pylori-infected male INS-GAS mice and to a lesser extent in uninfected mice, potentially by enhancing IL-10 function, which in turn decreased IFN-γ and IL-1β responses induced by H.pylori.

A novel helicobacter, 'Helicobacter macacae', was previously isolated from a colony of rhesus and cynomolgus monkeys in which diarrhoea from chronic idiopathic colitis was enzootic. A survey performed in a second colony of rhesus monkeys without a history of chronic diarrhoea determined that 57 % were faecal-culture positive for Helicobacter species. Ten years after the survey, one of the animals from which 'H. macacae' had been isolated, a 23-year-old, intact male rhesus monkey (Macaca mulatta), presented with partial inappetence and progressive weight loss. Subsequent evaluation of the monkey revealed anaemia, hypoproteinaemia, hypoalbuminaemia and a palpable abdominal mass. Contrast radiography suggested partial intestinal obstruction. The animal was euthanized and a diagnosis was made of intestinal adenocarcinoma of the ileocaecocolic junction with metastasis to regional lymph nodes and liver. Microaerobic culture of caecal tissue yielded a helicobacter organism identified as 'H. macacae' by 16S rRNA gene sequencing - the same species of bacteria isolated 10 years previously. The liver, small intestine and colon were also positive by PCR for Helicobacter species. Intestinal adenocarcinoma is the most common malignancy of aged macaques. Faeces or caecal tissue from five out of five monkeys that remained from the original cohort and that were colonized with 'H. macacae' in the initial survey were positive for the organism. The apparent persistence of 'H. macacae' in these animals, the isolation of the bacterium from animals with colitis and the recognition of the importance of inflammation in carcinogenesis raise the possibility of an aetiological role in the genesis of intestinal adenocarcinoma in aged rhesus monkeys.

The unique electrochemical properties of conductive polymers can be utilized to form stand-alone polymeric tubes and arrays of tubes that are suitable for guides to promote peripheral nerve regeneration. Noncomposite, polypyrrole (PPy) tubes ranging in inner diameter from 25 microm to 1.6 mm as well as multichannel tubes were fabricated by electrodeposition. While oxidation of the pyrrole monomer causes growth of the film, brief subsequent reduction allowed mechanical dissociation from the electrode mold, creating a stand-alone, conductive PPy tube. Conductive polymer nerve guides made in this manner were placed in transected rat sciatic nerves and shown to support nerve regeneration over an 8-week time period., ((c) 2008 Wiley Periodicals, Inc.)

Twenty-five (27 %) of 92 clinically normal macaques were found to have beta-haemolytic Escherichia coli isolated from their faeces. Five of six isolates chosen for further characterization had multiple antibiotic resistance and were PCR-positive for cytotoxic necrotizing factor 1 (cnf1) with a demonstrated cytopathic effect in vitro. By repetitive element sequence-based PCR genotyping, genetic similarity was established for selected isolates. We believe this to be the first report of E. coli strains producing CNF1 in non-human primates.

Background: Seizures were observed in a 16-year old male Guyanese squirrel monkey with a history of inappetence and weakness., Methods and Results: Complete blood count, biochemical profile, and urinalysis indicated systemic disease. Nematode larvae were detected in the feces. Cerebrospinal fluid (CSF) analysis revealed leukocytes and gram-positive cocci. Staphylococcus aureus was isolated from the CSF. Histopathological evaluation revealed systemic lesions with inflammation and nematodes in the small and large intestine., Conclusion: This is the first report describing spontaneous staphylococcal CNS infection in a squirrel monkey.

Acute respiratory distress syndrome (ARDS) is an important and potentially life-threatening complication in humans that arises subsequent to a variety of primary insults including noxious fume inhalation, infection, and trauma. Here we describe the first two cases of ARDS reported in association with postoperative complications in rhesus macaques. In agreement with the multifactorial nature of the human syndrome, ARDS in one monkey was attributed to sepsis, whereas in the other it was ascribed to neurogenic trauma. Despite the different etiologies, both monkeys demonstrated clinical features of ARDS, including progressive dyspnea and pulmonary edema, and syndrome-defining histopathologic criteria including edema with intraalveolar neutrophils, fibrinohemorrhagic effusions with crescentic membranes, and interstitial vascular degeneration. Recognition and aggressive treatment of ARDS at an early stage may improve survival rates in dyspneic nonhuman primates with underlying extrapulmonary diseases.

Gastric Helicobacter spp. are associated with chronic inflammation and neoplastic transformation in humans as well as domestic and laboratory species. The present study examined the association of Helicobacter heilmannii (Hhe) infection in pet cats with feline gastric mucosa associated lymphoid tissue (MALT) lymphoma. Tissues were collected via gastric biopsy or at necropsy from 47 pet cats with clinical signs of gastrointestinal disease, including vomiting and inappetance, and classified as gastritis (14/47), lymphoma (31/37), or normal (2/47). Tissues positive for argyrophilic organisms with Warthin-Starry stain (29/47) were assessed by fluorescent in situ hybridization (FISH) for the presence of Hhe strains 1-4 as well as with a fifth probe that detected Helicobacter salomonis, Helicobacter bizzozeronii, or Helicobacter felis. A significant association of positive Warthin-Starry status with Hhe infection was found in cases of sick cats (22/29; p<0.05 by Chi-square; chi(2)=7.034). Interestingly, a significant association between Hhe status and a diagnosis of lymphoblastic or lymphocytic lymphoma was observed as well in a subset of 24 Warthin-Starry positive lymphoma cases: of lymphoblastic lymphoma cases, 13/17 were positive for Hhe (p<0.05; chi(2)=4.854). Hhe strains 2 and 4 were most commonly found (18/29 and 17/29, respectively) among sick cats, although a higher than expected number of cats was also positive for Hhe1, which initial reports have described as rare in cats and common in humans. The association found between a positive Hhe status with the presence of feline gastric lymphoma, especially lymphoblastic lymphoma, argues for the need to conduct prospective studies to better identify the frequency and strain distribution of Hhe infection in both healthy and clinically ill cats, particularly those cats with gastric lymphoma.

Enterohemorrhagic Escherichia coli (EHEC) infection causes hemolytic uremic syndrome, a leading cause of acute renal failure in children. Dutch Belted (DB) rabbits are susceptible to EHEC-induced disease. Using real-time quantitative RT-PCR we measured the renal mRNA expression of cytokines and fibrinolytic factors in DB rabbits challenged with intravenous Shiga toxin 2 (Stx2) (1200 ng/kg). Group 1 rabbits received an incremental dose during an 8-day period whereas Group 2 rabbits received a single dose. Group 1 rabbits developed mild disease. In contrast, Group 2 rabbits developed severe diarrhea, higher levels of circulating polymorphonuclear leukocytes, increased mean platelet volume, and increased fibrinogen levels. Group 2 rabbits developed polymorphonuclear leukocyte infiltration in the intestine and kidney as well as glomerular congestion, luminal constriction, and mesangial glomerulonephropathy. These renal lesions were associated with up-regulation of interleukin-8 (P<0.006), plasminogen activator inhibitor-1 (P<0.04), and tissue plasminogen activator (P<0.05). Circulating Stx2 promoted dose-dependent enteritis and renal injury characterized by inflammation and impaired fibrinolysis leading to thrombosis.

Cystic renal diseases in domestic ferrets are a common anecdotal finding but have received scant systematic assessment. We performed a 17-y, case-control retrospective analysis of the medical records of 97 ferrets housed at our institution between 1987 and 2004, to determine the prevalence and morphotypes of cystic renal diseases in this species. Histologic sections stained with hematoxylin and eosin, Masson trichrome, or periodic acid-Schiff were evaluated by a comparative pathologist, and statistical analysis of hematologic and serum chemistry values was correlated with morphologic diagnosis. Of the 97 available records, 43 were eliminated due to lack of accompanying tissues. Of the 54 remaining cases, 37 (69% prevalence) had documented renal cysts, and 14 of the 54 ferrets (26%) had primary polycystic disease consisting of either polycystic kidney disease affecting renal tubules or, more commonly, glomerulocystic kidney disease. Secondary polycystic lesions were identified in 11 ferrets (20%), and 12 ferrets (22%) exhibited focal or isolated tubular cysts only as an incidental necropsy finding. Ferrets with secondary renal cysts associated with other developmental anomalies, mesangial glomerulopathy, or end-stage kidney disease had hyperphosphatemia and elevated BUN in comparison with those with primary cystic disease and elevated BUN compared with those without renal lesions. Although reflecting institutional bias, these results implicate primary and secondary cystic renal diseases as highly prevalent and underreported in the domestic ferret. In addition to the clinical implications for ferrets as research subjects and pets, these findings suggest a potential value for ferrets as a model of human cystic renal diseases.

Chronic idiopathic colitis is a common clinical entity in young captive rhesus monkeys. Eight isolates, cultured from five monkeys in colony 1 with endemic diarrhea and three from colony 2 without diarrhea, were grown under microaerobic conditions on selective agar and were classified by full 16S rRNA sequence, biochemical, and phenotypic analysis as a novel helicobacter, "Helicobacter macacae" (proposed name). All eight strains of H. macacae had 99.5% identical 16S rRNA sequences.

The incidence of gastric cancer is higher in men than women. Epidemiological studies suggest that female hormones reduce gastric cancer risk. We examined the effect of ovarian-dependent female hormones on Helicobacter pylori-induced gastric cancer in hypergastrinemic INS-GAS mice. Male and female sexually intact or ovariectomized (OVX) mice were inoculated with H.pylori SS1 or vehicle-only at 10 weeks of age, and tissues were evaluated at 16 or 28 weeks post-infection (WPI). A subset of OVX females were supplemented with 17beta-estradiol (E2), beginning at 16 WPI. Stomachs were evaluated by histopathology, Ki-67 proliferation index, H.pylori quantitative culture and quantitative polymerase chain reaction for messenger RNA expression of inducible nitric oxide synthase (iNOS) and inflammatory cytokines. Infected OVX females developed significantly more severe gastritis (P < 0.05) than infected intact females at both time points. E2 treatment in infected OVX females attenuated the severity of gastritis. Gastrointestinal intraepithelial neoplasia (GIN) developed in 42% of infected males and 10% of infected OVX females by 28 WPI, whereas infected intact females and E2-treated OVX females did not develop GIN. Infected OVX females showed significantly increased iNOS expression and epithelial cell proliferation when compared with intact, infected females. Likewise, interferon-gamma, tumor necrosis factor-alpha and interleukin-1beta (IL-1beta) expression in infected OVX females were significantly increased at 28 WPI when compared with intact counterparts. E2 treatment in infected OVX females significantly decreased IL-1beta expression, increased IL-10 expression and reduced epithelial cell proliferation. These results demonstrate a protective effect of E2 in H.pylori-induced gastric cancer in a mouse model.

Microbial infections are common sequelae in humans and animals implanted with long-term intravascular catheters. Understanding the pathophysiology of infectious morbidity is critical to improving quality of care in catheterized subjects. Here, we describe findings in 6 clinically healthy, male sheep implanted with indwelling aortic or cardiac catheters for 6 to 10 mo. We isolated multiple bacterial species including Serratia spp., Enterobacter agglomerans, Eschericia coli, Klebsiella oxytoca, and K. pneumoniae in aerobic cultures from catheter tips. Although sheep were clinically asymptomatic, 1 or both kidneys from all animals contained wedge-shaped infarcts of varying size and number. Microscopic examination revealed (a) marked fibrosis with mild inflammatory cell infiltrate consistent with chronic foreign body reaction around catheters; (b) moderate to severe, diffuse, subacute to chronic membranoproliferative glomerulonephritis and mild, multifocal chronic interstitial nephritis; and (c) mesangial immune-complex deposition as demonstrated by direct immunofluorescence technique. The finding of bacterial colonization of catheters together with chronic glomerulonephritis and immune-complex deposits in kidneys in clinically asymptomatic sheep underscores the need for close microbiologic monitoring of catheter implants and assessment of kidney function in animals instrumented for long-term vascular access.

We describe an unusual case of acute paraplegia in a young adult (7.5-month-old) Long-Evans rat that resulted from a spontaneous T-cell lymphoma. At presentation, a neurologic exam revealed normal pelvic limb flexor reflexes, the absence of an anal reflex, and deep pain recognition. Radiographs did not identify any obvious spinal abnormality or osseous trauma, although the liver and spleen were prominent. Hematologic analysis disclosed leukocytosis with atypical lymphocytes. At necropsy, red, friable to gelatinous masses were found associated with the ventral aspect of the vertebral column at the levels of the thoracic and lumbar vertebrae. Impression smears of the mass revealed a monocytic cell population with cells averaging 7 to 10 microm in diameter and having scant cytoplasm and pleomorphic nuclei, characteristics consistent with a lymphoid neoplasm. Histologically, the neoplasm was unencapsulated, poorly demarcated and highly infiltrative, invading and effacing the bone marrow and epidural space of the vertebral column. Neoplastic cells also were identified in the femoral bone marrow, spleen, liver, iliac and sacral lymph nodes, and lung. Immunophenotyping showed the neoplasm to be of T-cell origin. Although the lymphoma did not invade the meninges of the spinal cord, its impingement on the central and peripheral nervous systems resulted in foci of Wallerian degeneration that contributed to the paraplegia. This case report highlights the importance of having lymphoma and leukemia among the differential diagnoses in cases of acute paralysis in rodents.

Treatment of large defects requires the harvest of fresh living bone from the iliac crest. Harvest of this limited supply of bone is accompanied by extreme pain and morbidity. This has prompted the exploration of other alternatives to generate new bone using traditional principles of tissue engineering, wherein harvested cells are combined with porous scaffolds and stimulated with exogenous mitogens and morphogens in vitro and/or in vivo. We now show that large volumes of bone can be engineered in a predictable manner, without the need for cell transplantation and growth factor administration. The crux of the approach lies in the deliberate creation and manipulation of an artificial space (bioreactor) between the tibia and the periosteum, a mesenchymal layer rich in pluripotent cells, in such a way that the body's healing mechanism is leveraged in the engineering of neotissue. Using the "in vivo bioreactor" in New Zealand White rabbits, we have engineered bone that is biomechanically identical to native bone. The neobone formation followed predominantly an intramembraneous path, with woven bone matrix subsequently maturing into fully mineralized compact bone exhibiting all of the histological markers and mechanical properties of native bone. We harvested the bone after 6 weeks and transplanted it into contralateral tibial defects, resulting in complete integration after 6 weeks with no apparent morbidity at the donor site. Furthermore, in a proof-of-principle study, we have shown that by inhibiting angiogenesis and promoting a more hypoxic environment within the "in vivo bioreactor space," cartilage formation can be exclusively promoted.

Diseases associated with Escherichia coli infection are the subject of renewed interest due to emerging conditions such as hemolytic uremia syndrome. A collection of 15 strains of beta-hemolytic E. coli was isolated from diarrheic feces and diseased tissues of ferrets. All 15 strains were positive in specific PCR assays for the presence of hlyA, pap1, and cnf1. Seven of the cnf1-positive isolates were tested and shown to have a cytopathic effect on HeLa cell monolayers. The pathogenesis of these strains warrants future study.

The use of periosteum as a cell source for the in vitro engineering of grafts for articular cartilage repair requires the development of methods to obtain high viable cell numbers in the early stages of culture. In this study, we demonstrate that the addition of a mitogen, fibroblast growth factor-2 (FGF-2), during the early stage of the in vitro culture of periosteum in the presence of transforming growth factor-beta1 (TGF-beta1), significantly enhances cell proliferation, which results in increased neo-cartilage formation at later stages. Periosteal explants were cultured in vitro within alginate or agarose based gels in the presence of either FGF-2 for the first week, TGF-beta1 for the first 2 weeks, FGF-2 and TGF-beta1 for the first week and first 2 weeks respectively, or no added factors. Consistent with previous studies, periosteum derived neo-chondrogenesis occurred only in the presence of TGF-beta1. The neo-cartilage was found to contain cartilage specific proteoglycans and Type-II collagen as determined by safranin-O and immunohistochemical staining respectively. Further medium supplementation with FGF-2 stimulated early cell proliferation (>3 fold higher total DNA content per explant at day 10). This resulted in a marked increase in the size of the cultured explants and in the total area of the explant staining positive for safranin-O (from around 50% to 85%, (p<0.05)) after 6 weeks culture. The ability to generate significant quantities of neo-cartilage within a biocompatible and biodegradable matrix such as alginate, which lacks the immunogenicity of agarose, could open new pathways to utilizing such constructs in articular cartilage tissue engineering applications.

Periosteum has been promoted as a potential substrate for tissue engineering. Its principal virtues are that it has a source of pluripotential mesenchymal cells and chondrogenic growth factors located in the cambium layer, and it can serve as a template for directional evolution of neo-tissue. The clinical use and in vitro study of periosteum-derived neo-tissue has been limited by the level of surgical skill required for harvest. Precise surgical technique, task-specific experience, adequate volume of procedures, and general surgical expertise are required for optimal harvest using the traditional periosteal elevator method. This report describes an easily mastered technique that preserves viability while providing the harvest of relatively large amounts of periosteum. Skeletally mature New Zealand white rabbits (11 males/20 tibias; 4 females/8 tibias; approximate weight 3.5 kg) and one Yucatan miniature pig were used for harvest of periosteum from the tibia using the traditional periosteal elevator and the developed hydraulic elevation approach. Histologic examination of the periosteal explants obtained by the developed method showed preservation of the cambium layer containing the progenitor cells necessary for the generation of neo-cartilage. This technique provides a simple method of harvesting large segments (>5 cm x 1 cm) of periosteum in a single procedure and may facilitate better exploitation of periosteum in tissue engineering.

Background: Cystic kidney diseases are an important cause of morbidity and mortality in humans. Small animal models are needed to more fully explore the complex expression patterns and pathobiology of this group of heritable diseases., Methods: We performed a 15-year retrospective analysis of cases in our laboratory animal diagnostic archives to determine the prevalence of cystic kidney disease in New Zealand White rabbits., Results: Out of 203 records with documented renal histopathology, we identified and defined 7 cases of polycystic kidney syndrome (PKS) by 3 morphologic criteria: (1) cysts or microcysts derived from tubules, glomeruli, or both; (2) loose mesenchymal expansion of cortical and/or medullary interstitium; and (3) irregular thickening, thinning, and splitting of basement membranes. PKS was associated with hypercalcemia and hypercreatinemia (P < 0.01), and arterial mineralization resembling Mönckeberg's medial calcific sclerosis. In the liver, mild chronic cholangitis with cholangiodysplasia and fibrosis was common. Anorexia and lethargy were the clinical signs most often reported., Conclusion: Clinicopathologic characterization of PKS in New Zealand White rabbits revealed similarities to both autosomal-dominant and autosomal-recessive polycystic kidney diseases of humans. Awareness of polycystic kidney syndrome in New Zealand White rabbits will allow investigators to avoid using affected animals in unrelated renal research. Prospective studies are needed to define the underlying cause(s) of polycystic kidney syndrome in New Zealand White rabbits, which may be an important new small animal model of human cystic kidney diseases.

Helicobacter mustelae, the gastric pathogen of ferrets, produces an array of surface ring structures which have not been described for any other member of the genus Helicobacter, including H. pylori. The unique ring structures are composed of a protein named Hsr. To investigate whether the Hsr rings are important for colonization of the ferret stomach, ferrets specific pathogen free for H. mustelae were inoculated with an Hsr-deficient mutant strain or the wild-type H. mustelae strain. Quantitative cultures from antral biopsy specimens obtained at 3, 6, and 9 weeks postinoculation demonstrated no significant difference in the levels of bacteria in the ferrets that received the Hsr-negative strain and the ferrets infected with the parent strain. However, when the ferrets were biopsied at 12 and 15 weeks and necropsied at 18 weeks after infection, the levels of bacteria of the Hsr-negative strain in the stomach antrum were significantly reduced. This decline contrasted the robust antral colonization by the wild-type strain. The Hsr-negative strain did not efficiently colonize the gastric body of the study ferrets. Histological examination at 18 weeks postinoculation revealed minimal gastric inflammation in the animals that received the mutant H. mustelae strain, a finding consistent with its waning infection status, whereas lesions characteristic of helicobacter infection were present in ferrets infected with the wild-type strain. Scant colonization by the Hsr-negative H. mustelae strain at the end of the 18-week study, despite initial successful colonization, indicates an inability of the mutant to persist, perhaps due to a specific host response.

Ferrets with adrenal gland dysfunction have alopecia as their most common clinical sign of disease. Two cases of alopecia in neutered female ferrets are reported that were associated instead with neoplastic tissue found at the site of an ovarian pedicle. Androstenedione and 17-hydroxyprogesterone, but not estradiol, concentrations were high in both ferrets. Following surgical resection of the abnormal tissue in one ferret, the high hormone values decreased quickly and hair regrowth ensued. In both cases, histologic examination revealed features consistent with classical sex cord-stromal (gonadostromal) tumors: prominent spindle cells, along with polyhedral epithelial cells and cells with vacuolated cytoplasm. Although similiar cell types have been described in the adrenal glands of ferrets with adrenal-associated endocrinopathy, an ovarian origin for the current neoplasms is considered likely on the basis of their anatomic location; accessory adrenal tissue has only been described close to an adrenal gland or in the cranial perirenal fat of ferrets. Immunohistochemical analysis, using an antibody against Mullerian-inhibiting substance, failed to prove definitively the source of the steroidogenic cells.

Upper gastrointestinal examinations were performed in 11 unsedated ferrets and 4 ferrets sedated with ketamine and diazepam. Each animal received a 8-13 mL/kg body weight dosage of barium liquid (30% weight:volume). Radiographs were made immediately and at 5, 10, 20, 40, 60, 90, 120 and 150 min (mins) after the barium was administered. Gastric emptying began immediately. Mean total gastric emptying was longer in sedated ferrets (130 +/- 40 min versus 75 +/- 54 min); however, this difference was not statistically significant (p = 0.18). Small intestinal transit time was less than 2 h in all ferrets. The barium-filled small bowel was best visualized on the 20- and 40-min radiographs and did not exceed 5-7 mm in width. Flocculation of barium in the small intestine and adherence of barium to the stomach mucosa was seen in almost all animals. The longitudinal colonic mucosal folds in the colon were well visualized in the normal upper gastrointestinal study and aided in distinguishing small intestine from large intestine. The use of ketamine and diazepam sedation did not significantly affect the parameters evaluated in the upper gastrointestinal study series.

Enterohemorrhagic Escherichia coli (EHEC) causes hemorrhagic colitis and hemolytic-uremic syndrome (HUS) in humans. The exact mechanism by which EHEC induces disease remains unclear because of the lack of a natural animal model for the disease. An outbreak of bloody diarrhea and sudden death was investigated in a group of Dutch belted rabbits. Two of these rabbits harbored enteropathogenic E. coli O145:H(-), and 1 rabbit was coinfected with EHEC O153:H(-). A partial Shiga toxin 1 gene (stx1) fragment from E. coli O153:H(-) was confirmed by Southern blot and sequence analysis. Toxin production was demonstrated by a HeLa cell cytotoxicity assay. Histopathologic findings in all affected rabbits included erosive and necrotizing enterocolitis with adherent bacterial rods, proliferative glomerulonephritis, tubular necrosis, and fibrin thrombi within small vessels and capillaries. Our findings provide evidence for a naturally occurring animal model of EHEC-induced systemic disease that closely resembles human HUS.

To determine the prevalence of colonization by Corynebacterium ulcerans, we cultured samples from the cephalic implant-skin margin and pharynx of 26 rhesus macaques and one pig-tailed macaque. All but one of the samples from the cephalic implants yielded a mixed population of bacteria. C. ulcerans grew from the cephalic implants in 56% and from the pharynx in 3% of the implanted animals. We screened nine of these isolates for diphtheria toxin (DT) and phospholipase D (PLD). Polymerase chain reactions (PCR) failed to identify DT in any of the tested isolates, which also lacked DT activity in Elek tests. However, all nine isolates tested had PLD toxin activity as determined by conjoint hemolysis on sheep blood agar plates in the presence of equi factor (Rhodococcus equi). In addition, PCR assays and Southern blot hybridization confirmed the presence of pld in the isolates. The role of the PLD toxin in promoting colonization of cephalic implants by C. ulcerans is unknown. We found C. ulcerans to be a frequent contaminant of the cephalic implant-skin margin. Further studies are necessary to investigate the relative clinical importance of this organism and the efficacy of various implant maintenance protocols in preventing infection.

A natural infection with Helicobacter pylori (H. pylori) in domestic cats (Felis cattus) less than 2 years of age has been well described in a closed colony of animals. Six cats from this colony that were serially evaluated by culture, polymerase chain reaction, and light and electron microscopy for a period of 3 years demonstrated persistent gastric colonization with a single cag(-) vac(+) strain of H. pylori. In these cats, as well as five other 5- to 6-year-old cats that were examined, a long-term infection resulted in chronic diffuse lymphofollicular atrophic gastritis with areas of mucosal dysplasia in the antrum and predominantly midsuperficial gastritis in the body and cardia. Topographically, the distribution of lesions was similar in both young and older cats and closely resembled that found in humans, with the most severe changes occurring in the gastric antrum. Few granulocytes and no significant elevation in mast cells were seen in older H. pylori-infected cats compared with uninfected controls; however, marked increases in interepithelial globule leukocytes and numerous active mucosal lymphoid follicles were present in infected animals. Indices of gastritis were significantly greater in older infected cats when compared with uninfected controls and younger cats (P < 0.05). The antral cell proliferation index of infected older cats was significantly (P = 0.021) greater than that of uninfected controls. Apoptotic indices of the gastric antrum and body of infected cats were significantly (P = 0.01) increased versus controls. Chronic infection with H. pylori in cats shares many features of long-term H. pylori infection in humans, including the development of preneoplastic processes. This similarity provides useful, comparative insights into host-pathogen interactions.

In this study we designed and employed a novel experimental animal model for the examination of arterial and cardiopulmonary baroreceptors in the dynamic closed-loop short-term cardiovascular control of total peripheral resistance, and applied system identification to the analysis of fluctuations in mean arterial pressure, right atrial transmural pressure, and Total Peripheral Resistance to characterize quantitatively the physiologic mechanisms responsible for the couplings between these variables. For this purpose, conscious sheep were used; where both types of baroreceptors were exposed simultaneously to random independent beat pressure variations over a small range around their operating points (via atrial pacing and occlusion of the inferior vena cava), while total peripheral resistance was measured. Subsequently, system identification was applied to the analysis of beat-to-beat fluctuations in the measured signals.

Objective: To determine whether ranitidine bismuth citrate, clarithromycin, or a combination of ranitidine bismuth citrate and clarithromycin would be efficacious in eradication of Helicobacter mustelae infection in ferrets., Animals: 60 seven-month-old ferrets., Procedure: To determine dosages of clarithromycin and ranitidine bismuth citrate that would suppress growth of, but not eradicate infection with, H mustelae, ferrets (n = 6/group) were treated p.o. with clarithromycin or ranitidine bismuth citrate at various dosages. Efficacy of treatment was then determined by treating ferrets with clarithromycin alone, ranitidine bismuth citrate alone, or clarithromycin and ranitidine bismuth citrate. Gastric biopsy specimens were obtained before, during, and at various times after treatment and submitted for quantitative bacterial culture and histologic evaluation. Minimum concentrations of clarithromycin that inhibited 90% of the growth of isolates obtained before and after treatment were determined., Results: Dosages of clarithromycin and ranitidine bismuth citrate that suppressed growth of H mustelae were 12.5 and 24 mg/kg of body weight, p.o., every 8 hours, respectively. Infection was not eradicated in ferrets treated with ranitidine bismuth citrate alone but was eradicated in all 6 ferrets treated with clarithromycin and ranitidine bismuth citrate and in 4 of 6 treated with clarithromycin alone. A decrease in susceptibility to clarithromycin was detected for H mustelae isolates obtained after treatment. Mild or moderate antral gastritis was observed even in ferrets from which infection was eradicated., Conclusions and Clinical Relevance: A combination of ranitidine bismuth citrate and clarithromycin was efficacious in eradicating H mustelae infection from ferrets.

Background and Objective: Pregnancy toxemia may lead to appreciable mortality among jills and their offspring. The objective of this report was to increase awareness of the disease, its likely cause, and practical prevention and treatment measures., Methods: Ten cases of pregnancy toxemia were evaluated. Jills were in late gestation (mean, 38 days; range, 34 to 42 days) and had large litters (mean, 11.5 kits; range, 7 to 15 kits)., Results: The most common clinical signs of disease were lethargy, inappetence, dehydration, and excess shedding. Hematologic and clinical biochemical abnormalities included anemia (4 of 8 jills tested), hypoproteinemia (5 of 7), azotemia (7 of 7), hypocalcemia (5 of 6), hyperbilirubinemia (3 of 3), and high liver enzyme activities (6 of 6). Two jills were found dead; two jills were euthanized, six received supportive treatment, and cesarean section was performed on five. The three jills that survived tended to have less pronounced azotemia, hypoproteinemia, and liver enzyme activity increases and were not anemic. Hepatic lipidosis was observed grossly in all jills that died and was confirmed by histologic examination in four jills., Conclusions: Pregnancy toxemia in ferrets resembles metabolic diseases in several other animal species and requires aggressive treatment, including supportive care, nutritional supplementation, and cesarean section. Maintaining adequate nutrition and avoiding stress late in gestation may prevent the disease.

Background and Purpose: After myocardial necrosis and fibrosis was observed in five rabbits which had been anesthetized a variable number of times, the potential relationship of these lesions and anesthesia was evaluated in 35 other rabbits., Methods: Anesthesia was induced by intramuscular administration of ketamine and xylazine followed by infusion of lactated Ringer's solution also containing ketamine and xylazine. Group A rabbits (n = 9) were subjected to multiple anesthesias and were evaluated by echocardiography, thoracic radiography, electrocardiography, determination of serum coronavirus titer, vitamin E concentration, and complete necropsy. Prior to a single acute procedure followed by necropsy, group B rabbits (n = 11) were evaluated by echocardiography only. Group C rabbits (n = 10) had never been anesthetized and were necropsied after euthanasia. Group D rabbits (n = 5) had intermediate anesthesia exposure history and were evaluated by echocardiography only. Myocardial fibrosis was scored semi-quantitatively on a scale of 0 to 4., Results: Canine coronavirus test results were negative; hypovitaminosis E was evident, and fibrosis scores were significantly increased in group A, compared with group B or group C, rabbits., Conclusion: Etiologic differentials included alpha2-agonist-mediated coronary vasoconstriction with associated myocardial hypoperfusion, hypovitaminosis E and free radical injury, and other anesthetic-induced physiologic trespass.

Background: Helicobacter pylori has been cultured from the inflamed gastric mucosa of naturally and experimentally-infected cats. The lesions in the H. pylori-infected cat stomach mimic many of the features seen in human stomachs infected with H. pylori. This study sought to determine whether H. pylori-negative, specific pathogen-free cats with normal gastric mucosa were susceptible to colonization with a human cagA+ strain of H. pylori, and whether gastritis developed after infections., Methods: Four H. pylori-negative cats treated with cimetidine were orally dosed 3 times at 2-day intervals with 3 ml (1.5 x 108 CFU/ml) of H. pylori., Results: All experimentally-infected cats became persistently colonized as determined by H. pylori isolation from gastric tissue by culture at 12 weeks, and all 4 cats were found positive by PCR during serial gastric biopsies and necropsy at 15 weeks postinoculation. The 2 control cats did not have H. pylori isolated, nor was gastric tissue positive by PCR. The H. pylori isolated from the 4 experimentally-infected cats had RFLP patterns specific for the flaA gene identical to those of the inoculating strain. All 4 H. pylori-infected cats had multifocal gastritis, consisting of lymphoid aggregates plus multiple large lymphoid nodules. In the control cats, one cat had a few focal lymphocytic aggregates in the body submucosa, whereas the second cat had normal gastric mucosa., Conclusion: Human cagA+ H. pylori readily colonized the cat stomach and produced a persistent gastritis. The findings demonstrate the utility of the cat to study H. pylori induced pathogenesis.

An outbreak of diarrhea spanning 3 months occurred in a breeding colony of scid/Trp53 knockout mice. Approximately a third of the 150 mice were clinically affected, with signs ranging from mucoid or watery diarrhea to severe hemorrhagic diarrhea with mortality. Helicobacter bilis and the newly recognized urease-negative organism H. rodentium were isolated from microaerobic culture of feces or cecal specimens from affected mice. Dual infection with H. bilis and H. rodentium were confirmed by culture and polymerase chain reaction (PCR) in several animals. Both Helicobacter species rapidly colonized immunocompetent sentinel mice exposed to bedding from cages containing affected mice, but the sentinel remained asymptomatic. Mice with diarrhea had multifocal to segmental proliferative typhlitis, colitis, and proctitis. Several affected mice had multifocal mucosal necrosis with a few focal ulcers in the cecum, colon, and rectum. Mice with diarrhea were treated with antibiotic food wafers (1.5 mg of amoxicillin, 0.69 mg of metronidazole, and 0.185 mg of bismuth/mouse per day) previously shown to eradicate H. hepaticus in immunocompetent mice. Antibiotic treatment resulted in resolution of diarrhea, but not eradication of H. bilis and H. rodentium; mice continued to have positive PCR results after a 2-week treatment regimen, and clinical signs of diarrhea returned in some mice when treatment was suspended. To the authors' knowledge, this is the first report of natural infection with either H. bilis and/or H. rodentium causing acute diarrheal disease and suggests that H. bilis and/or H. rodentium can be an important pathogen for scid mice.

Objective: To address the physiologic mechanism of isoflurane-associated reduction in hematologic variables in ferrets., Animals: 6 young adult female ferrets., Procedure: Distribution of 99mTc-labeled autologous erythrocytes was measured by serial in vivo imaging. Data were recorded in 4 ferrets, using a gamma camera, immediately prior to anesthesia, 15 minutes after 2% isoflurane anesthesia in O2 via endotracheal tube, 1 minute prior to and throughout a 10-minute phenylephrine infusion, 20 and 40 minutes after termination of the phenylephrine infusion, and 45 minutes after termination of anesthesia. Blood indices were also measured at times that paralleled those for imaging. One ferret served as a conscious control (no anesthetic administration), and another as an isoflurane control (no phenylephrine administration)., Results: In ferrets under anesthesia, splenic radioactivity increased from baseline of 10.2 +/- 2.0% to 38.4 +/- 3.2% (mean +/- SEM; P < 0.05) of the injected dose. Splenic radioactivity decreased to 13.4 +/- 3.8% of the injected dose during phenylephrine infusion and to near baseline for the recovery image. Splenic radioactivity in the conscious control remained constant throughout the study, whereas that of the anesthetized control was persistently increased throughout administration of isoflurane. Percentage reduction of the 15-minute sample values, compared with baseline values for all hematologic indices, was: RBC count, 33% (P < 0.05); hemoglobin concentration, 34% (P < 0.05); hematocrit, 35% (P < 0.05); and plasma protein concentration, 20% (P < 0.05). All RBC variables returned to within 7 to 14% of baseline by 45 minutes after termination of anesthesia., Conclusion: Isoflurane anesthesia causes splenic sequestration of RBC in ferrets that is partially reversed by phenylephrine infusion or termination of anesthesia. Thus, investigators and clinicians should be cautious when interpreting hematologic findings in isoflurane-anesthetized ferrets, and accordingly, fluid treatment and transfusion should be planned.

Helicobacter mustelae, like Helicobacter pylori, possesses two flagellin proteins, FlaA and FlaB. Isogenic mutant strains of H. mustelae have been constructed by disruption of the flaA or flaB gene with a kanamycin resistance cassette or by introduction of both a kanamycin and a chloramphenicol resistance gene to produce a double mutant. To determine whether one or both flagellin proteins are necessary for colonization and persistence of infection with H. mustelae, 19 ferrets, specific pathogen free for H. mustelae, were given either the HMF1 flaA::km (weakly motile), ATCC 43772 flaB::km (moderately motile), or HMF1 flaA::cat flaB::km (non-motile) mutant strain, the wild-type parent strains, or sterile broth. Gastric tissue samples were obtained during sequential gastric biopsies beginning at 3 weeks postinoculation and ending at necropsy at 3 months postinoculation. H. mustelae infection status was determined by culture, histology, and serology. The wild-type parent strains of H. mustelae infected all ferrets at all time points. The double-mutant strain was unable to colonize; the flaA and flaB single-mutant strains were able to initially colonize at a low level and establish persistent infection with increasing numbers of organisms over time. The severity of gastritis produced by infection with these strains of H. mustelae correlated with the number of organisms present in the gastric mucosa. Flagellar motility is an important virulence factor for colonization and pathogenesis in the H. mustelae ferret model.