Consistency and effect of body position change on measurement of upper and lower esophageal sphincter geometry using impedance planimetry in a canine model.

The EndoFLIP (Endolumenal Functional Lumen Imaging Probe, Crospon Inc, Galway, Ireland) device uses the technique of impedance planimetry to evaluate dimensions and distensibility of the upper and lower esophageal sphincter. The null hypotheses for this study were that EndoFLIP variables would be stable between anesthestic episodes and would not be affected by body position when evaluating the upper and lower esophageal sphincters in healthy dogs. During each of three consecutive general anesthesia episodes administered to eight healthy adult research colony dogs with a standardized protocol, the EndoFLIP catheter was positioned to measure cross-sectional area, intrabag pressure, upper and lower esophageal sphincter length at two different balloon fill volumes (30 and 40 mL) and two body positions (lateral and dorsal recumbency). From these measured variables, a distensibility index was also calculated. Mixed effect analysis of variance was used to evaluate the fixed marginal and interaction effects of anesthesia episode, body position, and balloon volume on measured and calculated variables. For the upper esophageal sphincter significant interactions were present between anesthetic episode and body position for all variables except intrabag pressure; adjusting for body position significant differences were present between anesthetic episodes for all variables except distensibility index; adjusting for anesthetic episode cross-sectional area, intrabag pressure, upper esophageal sphincter length and distensibility index were all affected by body position. For the lower esophageal sphincter distensibility index was the only variable where a significant interaction between anesthesia episode and body position occurred; cross-sectional area, intrabag pressure, and lower esophageal length were not significantly affected by anesthesia episode when adjusting for body position; distensibility index was the only variable significantly affected by body position. Measurements of the geometry of the lower esophageal sphincter as measured by the EndoFLIP device were consistent under conditions of general anesthesia. Similar measurements taken at the upper esophageal sphincter displayed greater variability between anesthetic episodes and were affected to a greater extent by body position. Body position should be standardized in studies using the EndoFLIP to assess geometric and functional characteristics of the upper and lower esophageal sphincters.

Treatment of a heart base tumor and chylothorax with endovascular stent, stereotactic body radiation therapy, and a tyrosine kinase inhibitor in a dog.

An 8-year-old 28-kg male castrated rough collie was evaluated for persistent chylothorax secondary to right atrial mass. Cardiac ultrasound and computed tomography revealed a right atrial intra- and extraluminal mass with partial obstruction of the cranial vena cava and secondary chylothorax. Vascular stent placement was elected to alleviate cranial vena cava obstruction and secondary chylothorax. An 18 mm × 180 mm self-expanding stent was deployed in the region of the stricture, spanning the cranial vena cava and right atrium. An intrathoracic drainage catheter and subcutaneous port were placed within the right hemithorax, and antiplatelet therapy was initiated. Four weeks later, the dog underwent stereotactic body radiation therapy. Three months following treatment, the dog was diagnosed with supraventricular tachycardia and received antiarrhythmic therapy and antiangiogenic/antiproliferative medication (Palladia™). Subsequent evaluations confirmed the resolution of arrhythmia and pleural effusion. Combined vascular stent placement and stereotactic body radiation therapy for the treatment of a right atrial intraluminal and extraluminal mass leading to cranial vena cava compression and subsequent chylothorax may lead to long-term survival. A good outcome was achieved in this patient due to resolution of pleural effusion, as well as cytoreduction and presumably delayed progression of tumor growth.

Constraints on adaptation: explaining deviation from optimal sex ratio using artificial neural networks.

Determining processes constraining adaptation is a major challenge facing evolutionary biology, and sex allocation has proved a useful model system for exploring different constraints. We investigate the evolution of suboptimal sex allocation in a solitary parasitoid wasp system by modelling information acquisition and processing using artificial neural networks (ANNs) evolving according to a genetic algorithm. Theory predicts an instantaneous switch from the production of male to female offspring with increasing host size, whereas data show gradual changes. We found that simple ANNs evolved towards producing sharp switches in sex ratio, but additional biologically reasonable assumptions of costs of synapse maintenance, and simplification of the ANNs, led to more gradual adjustment. Switch sharpness was robust to uncertainty in fitness consequences of host size, challenging interpretations of previous empirical findings. Our results also question some intuitive hypotheses concerning the evolution of threshold traits and confirm how neural processing may constrain adaptive behaviour.

Eusociality and the success of the termites: insights from a supertree of dictyopteran families.

Sociality in insects may negatively impact on species richness. We tested whether termites have experienced shifts in diversification rates through time. Supertree methods were used to synthesize family-level relationships within termites, cockroaches and mantids. A deep positive shift in diversification rate is found within termites, but not in the cockroaches from which they evolved. The shift is responsible for most of their extant species richness suggesting that eusociality is not necessarily detrimental to species richness, and may sometimes have a positive effect. Mechanistic studies of speciation and extinction in eusocial insects are advocated.

Treatment of pancreatitis-associated extrahepatic biliary tract obstruction by choledochal stenting in seven cats.

OBJECTIVES: To report the clinicopathological findings and outcome in cats with pancreatitis-associated extrahepatic biliary tract obstruction (EHBO) treated by choledochal tube stenting. METHODS: Medical records of cats with EHBO secondary to pancreatitis that underwent choledochal stenting were reviewed. Information on outcome was obtained by re-examination of the cat or by telephone interview with the owners. RESULTS: All cats had pancreatitis confirmed by histopathological examination of biopsy samples (n=6) or suspected based on gross examination at surgery (n=1). In six cats, a section of 3.5 to five French gauge red rubber catheter and in one cat a section of 22 G intravenous catheter were used as a choledochal stent. Two cats developed re-obstruction of the biliary tract within a week of the original surgery. One cat had confirmed episodes of ascending cholangitis postoperatively. Two cats had chronic intermittent vomiting in the postoperative period. Two cats died during the perioperative period. Five cats survived to discharge, three of which died seven to 24 months postoperatively and two of which remain alive to date. CLINICAL SIGNIFICANCE: Choledochal stenting is an alternative to biliary diversion for management of feline pancreatitis-associated EHBO in select cases. However, there may be greater morbidity with this technique in cats compared with dogs.

Complication rate, outcome, and risk factors associated with surgical repair of fractures of the lateral aspect of the humeral condyle in dogs.

OBJECTIVE: To determine outcome, report complications, and risk factors for complications associated with the surgical treatment of fractures of the lateral aspect of the humeral condyle (FLHC) in dogs. STUDY DESIGN: Fifty dogs with FLHC that had been repaired surgically were included in this retrospective case series. METHODS: The medical records and radiographs from 50 dogs with FLHC from 1990--2006 were analyzed. RESULTS: The complication rate was 30%. For every 30-minute increase in surgical time the odds of a complication increased by 2.00 (95% CI: 1.06, 3.77). For every 10 degrees increase in the angle between the transcondylar screw and a line between the epicondyles viewed on a craniocaudal radiograph there was a 4.82 (95% CI: 1.23, 18.86) greater odds of an intracondylar fracture gap appearing on postoperative radiographs. When an intracondylar fracture gap was present after surgery there was a 25% long-term radiographic outcome failure rate, whereas there was a 0% radiographic failure rate in the dogs in which an intracondylar fracture gap was not present. In conclusion, transcondylar screw placement parallel to the epicondylar line should be attempted for the repair of FLHC. An increase in surgical time leads to an increase in postoperative complication rate. The presence of an intracondylar fracture gap may be associated with fracture failure. CLINICAL SIGNIFICANCE: Screw angulation predisposed to postoperative intracondylar fracture gap which in turn may be associated with higher fracture fixation failure rate. The dogs that had prolonged surgical times had an increased complication rate.

Effect of Laparoscopic-assisted Gastropexy on Gastrointestinal Transit Time in Dogs.

BACKGROUND: Prophylactic gastropexy has been promoted as a means of preventing gastric volvulus during gastric dilatation and volvulus (GDV) syndrome. Little is known about the impact of gastropexy on gastrointestinal transit time. HYPOTHESIS: Laparoscopic-assisted gastropexy (LAG) will not alter gastrointestinal transit times when comparing gastric (GET), small and large bowel (SLBTT), and whole gut transit times (TTT) before and after surgery. ANIMALS: 10 healthy client-owned large-breed dogs. METHODS: Prospective clinical trial. Before surgery, all dogs underwent physical examination and diagnostic evaluation to ensure normal health status. Dogs were fed a prescription diet for 6 weeks before determination of gastrointestinal transit with a wireless motility capsule. LAG was then performed, and dogs were fed the diet for 6 additional weeks. Measurement of transit times was repeated 6 weeks after surgery. RESULTS: Ten dogs of various breeds at-risk for GDV were enrolled. No complications were encountered associated with surgery or capsule administration. There were no significant differences in GET 429 [306-1,370] versus 541 [326-1,298] (P = 0.80), SLBTT 1,243 [841-3,070] versus 1,540 [756-2,623] (P = 0.72), or TTT 1,971 [1,205-3,469] versus 1,792 [1,234-3,343] minutes (median, range) (P = 0.65) before and after LAG. CONCLUSIONS AND CLINICAL IMPORTANCE: An effect of LAG on gastrointestinal transit time was not identified, and wireless motility capsule can be safely administered in dogs after LAG.

Discrimination between cases of hip fracture and controls is improved by hip structural analysis compared to areal bone mineral density. An ex vivo study of the femoral neck.

In vivo bone densitometry is affected by measurement inaccuracies arising from the assumptions made about soft tissue and marrow composition. This study tested the hypothesis that section modulus (SM, a measure of bending resistance) when measured ex vivo, would discriminate cases of hip fracture from controls better than areal bone mineral density (aBMD). The biopsies were from (n = 22, female) subjects that had suffered an intracapsular hip fracture. The control material (n = 24, female) was from post-mortem subjects. Serial peripheral quantitative computed tomography (pQCT) 1-mm thick cross-sectional images of femoral neck previously embedded in methacrylate were obtained with the Densiscan 1000 pQCT densitometer and matched for lateral location. The image voxels were converted to units of bone mass, which were then used to derive the section modulus. The data were used to derive means from which receiver operating characteristic (ROC) curves could be generated. The area under the curves (AUC) showed that discrimination between the fracture cases and controls was better for SM than aBMD [SM: AUC = 0.83 (95% confidence interval: 0.71, 0.96), aBMD: AUC = 0.70 (0.54, 0.85); P = 0.034]. To simulate the forces experienced during a sideways fall, the model's neutral axis was rotated by 210 degrees. The results for section modulus were predictable from those at 0 degrees (r(2) = 0.97). We conclude that biomechanical analysis of the distribution of bone within the femoral neck may offer a marked improvement in the ability to discriminate patients with an increased risk of intracapsular fracture. Progress towards implementing this form of analysis in clinical densitometry should improve its diagnostic value, but may depend in part on better image resolution and more accurate corrections for the variability between subjects in regional soft tissue composition.

Mixed sex allocation strategies in a parasitoid wasp.

The sex allocation strategy of the parasitoid Laelius pedatus (Hymenoptera: Bethylidae) on different-sized hosts was investigated. The wasp lays from one to five eggs, and clutch size increases with host size. On the smallest hosts, single male eggs are laid, while on slightly larger hosts single female eggs are laid. On still larger hosts, gregarious clutches are laid which nearly always consist of a single male and one or more female eggs. The sex ratio strategy of the wasp appears to be influenced by a combination of local mate competition and conditional sex expression based on host quality.

Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in German Shepherd Dogs, Golden Retrievers, Labrador Retrievers, and Rottweilers.

OBJECTIVE: To determine whether age, breed, sex, weight, or distraction index (DI) was associated with the risk that dogs of 4 common breeds (German Shepherd Dog, Golden Retriever, Labrador Retriever, Rottweiler) would have radiographic evidence of degenerative joint disease (DJD) associated with hip dysplasia. DESIGN: Cross-sectional prevalence study. ANIMALS: 15,742 dogs. PROCEDURE: Hips of dogs were evaluated radiographically by use of the ventrodorsal hip-extended view, the compression v ew, and the distraction view. The ventrodorsal hip-extended view was examined to determine whether dogs had DJD. For each breed, a multiple logistic regression model incorporating age, sex, weight, and DI was created. For each breed, disease-susceptibility curves were produced, using all dogs, regardless of age, and dogs grouped on the basis of age. RESULTS: Weight and DI were significant risk factors for DJD in all breeds. For German Shepherd Dogs, the risk of having DJD was 4.95 times the risk for dogs of the other 3 breeds combined. In all breeds, the probability of having DJD increased with age. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that the probability of having hip DJD increased with hip joint laxity as measured by use of DI. This association was breed-specific, indicating that breed-specific information on disease susceptibility should be incorporated when making breeding decisions and when deciding on possible surgical treatment of hip dysplasia.

Self-reported offending, victimization, and the British Crime Survey.

Both the 1982 and 1984 British Crime Surveys contained questions on self-reported offending. In 1984 the questions were changed in order to try and improve admission rates. This article looks at the effect of this change. Admission rates in 1984 are shown to be approximately double those in 1982. Also examined are differences between offenders and non-offenders, what offenses 1984 respondents saw other people as engaging in most often, and who saw other people as least law abiding. The relationship between self-reported offending and victimization in both this and Gottfredson's (1984) analysis of BCS data is taken up.

Communicating with individuals with dementia. The impaired person's perspective.

1 To better meet needs of individuals with dementia, caregivers should focus on receiving and interpreting verbal and nonverbal messages conveyed by the afflicted individuals. 2 Prior research has focused on enhancing communication from caregivers to individuals with dementia; however, the content and meaning of communication received from individuals with dementia remains largely unexplored. 3 This study demonstrates that individuals with dementia are able to transmit meaningful communication and this communication can be interpreted by others, making client-centered interventions possible with this population. 4 If care models based on communication interpretation techniques can be built, perhaps the needs of individuals with dementia can be better met, tensions reduced, problematic behaviors decreased, and quality of life enhanced.

Body cavity lipomas in six dogs.

Histologically confirmed lipomas were surgically removed from the thoracic or abdominal cavities of six dogs. Three dogs had a large intra-abdominal mass causing severe abdominal distension. Two dogs had a mass extending into the pelvic canal, compressing the colon and causing obstipation. One dog with an intrathoracic mass had a history of coughing and intermittent cyanosis. All dogs had complete resolution of signs after surgical resection of the tumour. Recurrence occurred in one dog with an abdominal lipoma, two years after the initial surgery. This recurrent lipoma was treated successfully by surgical resection.

Simultaneous use of bilateral caudal superficial epigastric axial pattern flaps for wound closure in a dog.

A neutered male German shorthaired pointer sustained severe bite wounds to the left caudal flank and thigh area. Thorough wound lavage and debridement was performed immediately and also three days after presentation. Daily wound dressing resulted in the production of a mature granulation tissue bed. Prior to wound closure, colour flow Doppler ultrasonography was used to confirm blood flow through the right and left caudal superficial epigastric arteries and veins. Sixteen days after presentation, right and left caudal superficial epigastric axial pattern flaps were simultaneously elevated to cover the defect. The right flap was elevated as an island flap, rotated 120 degrees and used to cover the caudodorsal aspect of the defect. The left flap was elevated and rotated dorsally to cover the cranioventral aspect of the defect. Ninety per cent wound coverage was achieved and flap survival was total. The donor site defect was closed primarily and no dehiscence occurred. Three months postsurgery, the entire defect was closed and limb function was normal.

Pathogenesis and outcome of extrahepatic biliary obstruction in cats.

Extrahepatic biliary obstruction (EHBO) was confirmed at surgery or necropsy in 22 cats. Biliary or pancreatic adenocarcinoma was diagnosed by histopathology in six cats and one cat had an undiagnosed mass in the common bile duct. The remaining 15 cats had at least one of a complex of inflammatory diseases including pancreatitis, cholangiohepatitis, cholelithiasis and cholecystitis. The most common clinical signs were jaundice, anorexia, lethargy, weight loss and vomiting. Hyperbilirubinaemia was present in all cases. Distension of the common bile duct and gall bladder was the most commonly observed finding on abdominal ultrasound. Nineteen cats underwent exploratory laparotomy for biliary decompression and diversion. Mortality in cats with underlying neoplasia was 100 per cent and, in those with non-neoplastic lesions, was 40 per cent. Long-term complications, in those that survived, included recurrence of cholangiohepatitis, chronic weight loss and recurrence of obstruction. Based on these findings, the prognosis for EHBO in cats must be considered guarded.

Planning to meet the JCAHO standard: consideration of scientific findings.

Bringing research findings into practice does take some thought and planning, but most health care institutions already have committees, departments, and positions that can facilitate research utilization. It may just take some assessment of the roles and functions of these components to more carefully plan for systematic use of research findings in practice. This planning will pay off by enhancing the quality of nursing care and providing documentation that review of policies and procedures includes consideration of current scientific and nursing research findings.

Evaluating research for use in practice.

Before using research in practice, nurses must adequately evaluate both the scientific merit of the research and its potential impact on practice. This column outlined some basic questions that nurses can ask when reading research for use in practice. Many references in the nursing literature may be helpful to nurses who want to increase their skill in evaluating research for use in their own practice settings (Alderman, 1985; Haller et al., 1979; Jacox & Prescott, 1978; Stetler & Marram, 1976; Topham & DeSilva, 1988). Clinical nurses have tangible knowledge of their own practice settings. This knowledge makes them the ideal decision-makers in determining when research findings are suitable for their practice. They should continue to develop their skills in evaluating research and form networks with nurse researchers, nursing faculty, clinical nurse specialists, and others with advanced research preparation to assist them in evaluating research and to validate their own assessment of the research. This kind of collaboration will promote prudent use of research findings in nursing practice.

The importance of the practicing nurse in nursing research.

Most research findings never reach the practicing nurse. However, many scientific findings would enhance quality of care if nurses knew about them and incorporated them into their practice. To make nursing research practice based, medical-surgical nurses must identify pertinent questions for research and use the findings in practice and evaluate subsequent outcomes.

Research and quality management studies: ethical considerations.

Federal legislation requires that an IRB must review all research studies receiving federal funding and involving human subjects for the protection of human rights. In addition there must be a provision for informed consent so that subjects can freely choose whether or not to participate. Most health care agencies have adopted this as the standard for conducting research. The ethical principles of respect for persons, beneficence, and justice, guide review boards in making decisions for protecting human subjects. The standards for conducting QM studies have not been as explicit, but it seems that similar ethical principles could provide a guiding framework. To protect human subjects in QM studies, it has been suggested that studies be submitted to an IRB when they: (a) are prospective, (b) have potential scientific merit, and/or (c) may have application beyond the study setting. In addition even when data are coming from existing sources or patient records and used only for evaluation purposes within the study setting, mechanisms for ensuring privacy, confidentiality, and consent need consideration.

Identifying fall risk factors in preparation for reducing the use of restraints.

Nurses have a responsibility to maximize safety while minimizing the use of restraints. Assessment of fall risk factors for a specific population can aid in planning alternatives to the use of restraints while maximizing safety.