Ischemic postconditioning does not attenuate ischemia-reperfusion injury of rabbit small intestine.

Objective: To determine whether ischemic postconditioning can attenuate intestinal ischemia-reperfusion (I-R) injury and has a beneficial effect on tissue blood flow during reperfusion.

Study Design: In vivo experimental study.

Animals: New Zealand White rabbits (n=6).

"Gastric bascule": an unusual form of gastric volvulus.

Gastric volvulus can occur along the organoaxial axis or the mesenteroaxial axis. We present a patient with a gastric bascule: a gastric volvulus due to two lead points. A 17-year-old boy with dextrogastria, asplenia, and left diaphragmatic eventration presented with acute onset of nonbilious emesis, jaundice, and diffuse abdominal tenderness.

Stressor exposure disrupts commensal microbial populations in the intestines and leads to increased colonization by Citrobacter rodentium.

The gastrointestinal tract is colonized by an enormous array of microbes that are known to have many beneficial effects on the host. Previous studies have indicated that stressor exposure can disrupt the stability of the intestinal microbiota, but the extent of these changes, as well as the effects on enteric infection, has not been well characterized. In order to examine the ability of stressors to induce changes in the gut microbiota, we exposed mice to a prolonged restraint stressor and then characterized microbial populations in the intestines using both traditional culture techniques and bacterial tag-encoded FLX amplicon pyrosequencing (bTEFAP).

Adenomatous polyp with intestinal metaplasia of the esophagus (Barrett esophagus) in a dog.

Multiple endoscopic biopsy specimens of esophageal mucosa were received from a 13-year-old castrated male standard Poodle. The dog was presented for painful swallowing. Endoscopically, the distal aspect of the esophagus was inflamed with a polypoid mass that protruded into the esophageal lumen.

Piglet models of acute or chronic Clostridium difficile illness.

We examined the piglet model of Clostridium difficile illness (CDI) in humans, because swine are naturally susceptible to C. difficile. The piglet is a reproducible model of acute or chronic CDI with characteristic pseudomembranous colitis.

Ability of recombinant human bone morphogenetic protein 2 to enhance bone healing in the presence of tobramycin: evaluation in a rat segmental defect model.

Objective: To determine whether locally applied tobramycin influences the ability of recombinant human bone morphogenetic protein 2 (rhBMP-2) to heal a segmental defect in the rat femur.

Methods: The influence of tobramycin on the osteogenic differentiation of mesenchymal stem cells was first evaluated in vitro. For the subsequent, in vivo experiments, a 5-mm segmental defect was created in the right femur of each of 25 Sprague-Dawley rats and stabilized with an external fixator and four Kirschner wires.

Missense mutations in a retinal pigment epithelium protein, bestrophin-1, cause retinitis pigmentosa.

Bestrophin-1 is preferentially expressed at the basolateral membrane of the retinal pigmented epithelium (RPE) of the retina. Mutations in the BEST1 gene cause the retinal dystrophies vitelliform macular dystrophy, autosomal-dominant vitreochoroidopathy, and autosomal-recessive bestrophinopathy. Here, we describe four missense mutations in bestrophin-1, three that we believe are previously unreported, in patients diagnosed with autosomal-dominant and -recessive forms of retinitis pigmentosa (RP).

Higher-order aberrations produce orientation-specific notches in the defocused contrast sensitivity function.

Local minima or notches in the defocused contrast sensitivity function (CSF) have been linked to the aberrations of the eye. We use theoretical modeling of the effects of the aberrations to show these notches can be orientation-selective due to the effects of aberration terms such as coma and trefoil. Notches that changed with orientation were observed in the defocused CSF of four subjects.

The importance of grating orientation in contrast sensitivity following refractive surgery.

Higher-order aberrations degrade visual performance when the pupil is large, particularly in eyes that have abnormally high amounts of aberrations, such as those that have undergone refractive surgery. Geometrical optics predicts that asymmetrical aberrations such as coma can produce orientation selective effects, much like uncorrected astigmatism. Coma is also one of the main aberrations to increase following refractive surgery.

Abomasal parasite syndrome in North American elk (Cervus elaphus canadensis).

Case History: An 18-month clinical course of chronic ill-thrift, weight loss and emaciation, and eventual death occurred in a group of 520 translocated elk of mixed age and sex. Translocation was carried out without regard to animal welfare or health risks associated with the translocation. Mortality was approximately 84% (436/520) despite supportive nutritional and medical treatment.

Summation characteristics of the detection of compound gratings.

Many classical experiments have shown that two superimposed gratings are more easily detected than a single grating, in keeping with probability theory. Here we test the rules for the detection of 2-component compound gratings by extending the range of parameters used in previous experiments. Two complementary methods of deriving summation indices are described.

Evaluation of an adolescent hospital-based injury prevention program.

Background: IMPACT (Impaired Minds Produce Actions Causing Trauma) is an adolescent, hospital-based program aimed to prevent injuries and their consequences caused by alcohol or drug impairment and other high-risk behaviors. The overall objective of this evaluation was to determine the effect of the program on students' knowledge and behavior regarding drinking and driving, over time.

Methods: A randomized control trial between students randomly selected to attend IMPACT and those not selected served as a control group.

Nasal-temporal differences in cone-opponency in the near peripheral retina.

The purpose of this study is to establish whether nasal-temporal differences in cone photoreceptor distributions are linked to differences in colour matching performance in the two hemi-fields. Perceived shifts in chromaticity were measured using an asymmetric matching paradigm. They were expressed in terms of hue rotations and relative saturation changes and also in terms of activation levels of L-M or S-(L+M) cone-opponent channels.

Contrast sensitivity based orientation changes in refractive surgery patients.

It is well known that refractive surgery leads to an increase in higher-order aberrations. These can cause problems such as glare, starburst and halos in vision, particularly in low light levels when the pupil is large. The overall wavefront aberration of the eye is typically non-circularly symmetric due to the presence of aberrations such as coma and trefoil.

Microvascular changes in radiation-induced oral mucositis.

Background: Mucositis is one of the most debilitating side effects of head and neck cancer therapy and is currently believed to arise from an inflammatory cascade leading to cellular damage. However, no effective treatment has been identified despite extensive attempts with anti-inflammatory medications.

Objective: To compare real-time microvascular inflammatory changes with oral mucositis levels in patients undergoing radiotherapy or chemoradiotherapy for head and neck tumours.

Gnotobiotic piglet infection model for evaluating the safe use of antibiotics against Escherichia coli O157:H7 infection.

Background: Shiga toxin (Stx)-producing Escherichia coli (STEC), especially O157:H7, cause bloody diarrhea, and in 3%-15% of individuals the infection leads to hemolytic uremic syndrome (HUS) or other complications. Use of antibiotics to treat STEC infections is controversial. Here, we describe the use of piglets to evaluate the efficacy and mechanism of action of antibiotics in these infections.

Low-dose inhaled carbon monoxide attenuates the remote intestinal inflammatory response elicited by hindlimb ischemia-reperfusion.

Heme oxygenase (HO) represents the rate-limiting enzyme in the degradation of heme into carbon monoxide (CO), iron, and biliverdin. Recent evidence suggests that several of the beneficial properties of HO, may be linked to CO. The objectives of this study were to determine if low-dose inhaled CO reduces remote intestinal leukocyte recruitment, proinflammatory cytokine expression, and oxidative stress elicited by hindlimb ischemia-reperfusion (I/R).

Anaplastic astrocytoma in the spinal cord of an African pygmy hedgehog (Atelerix albiventris).

A 2-year-old, female hedgehog presented with an 8-month history of progressive, ascending paresis/paralysis and was tentatively diagnosed with wobbly hedgehog syndrome. She died awaiting further diagnostic tests, and the owners consented to postmortem examination. Grossly, the bladder was large and flaccid and the cervical and lumbar spinal cord were regionally enlarged, light grey, and friable with multifocal hemorrhages.

Chimeric GB virus B genomes containing hepatitis C virus p7 are infectious in vivo.

Background/aims: The development of new therapies for hepatitis C virus (HCV) infection has been hampered by the lack of a small animal model. GB virus B (GBV-B), which infects new world monkeys, has been proposed as a surrogate system for HCV replication. Despite their short genetic distance, however, difficulties exist when extrapolating results from GBV-B to the HCV system.

Measurement of macular pigment optical density and distribution using the steady-state visual evoked potential.

The purpose of this study was to specify isoluminance at different retinal eccentricities and to characterize macular pigment optical density (MPOD) and distribution using the steady-state visual evoked potential (VEP). Redgreen (B/G) gratings were generated within two circular stimulus fields (radius = 0.55 or 1.

Reaction time measures of adaptation to chromatic contrast.

Simple reaction times (RTs) were measured to brief temporally blurred (total onset 570 ms) Gaussian isoluminant chromatic patches (s.d. 0.

L- and M-cone isolating ERGs: LED versus CRT stimulation.

Using double silent substitution, it is possible to generate L-cone and M-cone isolating electroretinograms (ERGs) on a CRT. A major limitation of the technique is that the depth of modulation of cone classes is limited by the restricted luminance of the phosphors and their spectral overlap. To address this problem we have ported the technique to a four-color LED Ganzfeld stimulus (Diagnosis ColorDome).