bluuebunny/crossref_metadata_2025 huggingface dataset:
MAGNETIC RESONANCE IMAGING FEATURES OF SINONASAL DISORDERS IN HORSES
Authors: Tessier Caroline , Brühschwein Andreas , Lang Johann , Konar Martin , Wilke Markus , Brehm Walter , Kircher Patrick
Published: March 2013

Diseases of paranasal sinuses and nasal passages in horses can be a diagnostic challenge because of the complex anatomy of the head and limitations of many diagnostic modalities. Our hypothesis was that magnetic resonance (MR) imaging would provide excellent anatomical detail and soft tissue resolution, and would be accurate in the diagnosis of diseases of the paranasal sinuses and nasal passages in horses. Fourteen horses were imaged. Inclusion criteria were lesions located to the sinuses or nasal passages that underwent MR imaging and subsequent surgical intervention and/or histopathologic examination. A low field, 0.3 tesla open magnet was used. Sequences in the standard protocol were fast spin echo T2 sagittal and transverse, spin echo T1 transverse, short‐tau inversion recovery (STIR) dorsal, gradient echo 3D T1 MPR dorsal (plain and contrast enhanced), spin echo T1 fatsat (contrast enhanced). Mean scan time to complete the examination was 53 min (range 39–99 min). Lesions identified were primary or secondary sinusitis (six horses), paranasal sinus cyst (four horses), progressive ethmoid hematoma (two horses), and neoplasia (two horses). The most useful sequences were fast spin echo T2 transverse and sagittal, STIR dorsal and FE3D MPR (survey and contrast enhanced). Fluid accumulation, mucosal thickening, presence of encapsulated contents, bone deformation, and thickening were common findings observed in MR imaging. In selected horses, magnetic resonance imaging is a useful tool in diagnosing lesions of the paranasal sinuses and nasal passages.
VERTEBRAL HEART SCORES IN EIGHT DOG BREEDS
Authors: Jepsen‐Grant K. , Pollard R.E. , Johnson L.R.
Published: March 2013

The vertebral heart score (VHS) measurement is commonly used to provide a more objective measurement of cardiomegaly in canines. However, several studies have shown significant breed variations from the value previously established byBuchanan andBücheler (9.7 ± 0.5). This study describesVHSmeasurements inPug,Pomeranian,YorkshireTerrier,Dachshund,Bulldog,ShihTzu,LhasaApso, andBostonTerrier dog breeds. Dogs with two or three view thoracic radiographs, no subjective radiographic evidence of cardiomegaly, and no physical examination findings of heart murmurs or gallop rhythms were included in the study. ThePug,Pomeranian,Bulldog, andBostonTerrier groups were found to have aVHSsignificantly greater than 9.7 ± 0.5 (P< 0.00001,P= 0.0014,P< 0.0001,P< 0.00001, respectively). Body condition score (BCS) was found to have a significant effect on theVHSofLhasaApso group. Anomalous vertebrae in the thoracic column were associated with a significant increase inVHSof theBulldog (P= 0.028) andBostonTerrier (P= 0.0004) groups. Thoracic depth to width ratio did not have a significant effect onVHS.
EFFECTS OF FUROSEMIDE ON URETERAL DIAMETER AND ATTENUATION USING COMPUTED TOMOGRAPHIC EXCRETORY UROGRAPHY IN NORMAL DOGS
Authors: Secrest Scott , Essman Stephanie , Nagy Jesse , Schultz Loren
Published: March 2013

One of the limitations of computed tomographic excretory urography (CTEU) for diagnosis of ureteral disease in dogs is that normal ureteral peristalsis can cause intermittent and inconsistent filling. The aims of this study were to determine if the addition of furosemide to a standard CTEU protocol would increase identification of the ureteral segments, increase ureteral attenuation and increase ureteral diameter in normal dogs. Standard and furosemide‐enhanced CTEU scans were acquired in 14 healthy dogs 3 and 10 minutes postcontrast. Ureteral diameters, attenuation values, and percent ureteral filling scores were recorded without the knowledge of furosemide treatment. Comparisons were made between treatments for each postcontrast scan time. The addition of furosemide to the CTEU protocol improved visualization of the ureters by significantly increasing the number of ureteral segments that were able to be identified, as well as their diameter when imaging the patient 3 min following contrast injection (P = 0.012). No major side effects were observed at the dose of 4 mg/kg. There was no advantage to imaging dogs 10 min following contrast administration as the ureteral segments were less attenuating and a smaller percentage of the ureter could be identified. We conclude that the addition of furosemide to canine CTEU studies is safe and may help improve visualization of the ureters.
EVALUATION OF CANINE PROSTATE INTRAFRACTIONAL MOTION USING SERIAL CONE BEAM COMPUTED TOMOGRAPHY IMAGING
Authors: Harmon Joseph , Yoshikawa Hiroto , Custis James , LaRue Susan
Published: March 2013

This study used kilovoltage (kV) cone beam computed tomography (CBCT) imaging to characterize canine intrafractional prostate motion during hypofractionated stereotactic radiotherapy treatment. Serial CBCT images taken just prior to initiating treatment, and at several times during the treatment session, were acquired throughout the course of treatment for canine patients. All patients were immobilized in dorsal recumbency while using an air‐inflated rectal balloon. For each treatment session, rigid registration of intrafraction CBCT images with the interfraction CBCT used for setup verification was performed. Contours of the prostate and urethra were drawn on each CBCT image set and the center of mass for each structure was evaluated as a function of time. A total of seven canine patients was included in the study, resulting in 41 CBCT images collected during a total of 12 treatment sessions. Over 70% of our data were collected for CBCTs taken between 20 and 51 min after final patient setup was complete. The mean intrafraction movement in a single direction for the prostate and urethra was ≤0.14 mm and ≤0.22 mm, respectively. The maximum intrafraction movement for the prostate and urethra was ≤ 1.60 mm and ≤ 2.00 mm, respectively. The maximum variability in intrafraction movement for the prostate and urethra, as defined by two standard deviations, was ≤1.40 mm and ≤1.50 mm, respectively. Minimal intrafraction variability using appropriate patient positioning and rectal balloon, combined with kV CBCT image‐guided radiation therapy tools to account for interfraction changes, permit accurate and precise targeting of structures of interest.
EVALUATION OF TWO OBJECTIVE METHODS TO OPTIMIZE KVP AND PERSONNEL EXPOSURE USING A DIGITAL INDIRECT FLAT PANEL DETECTOR AND SIMULATED VETERINARY PATIENTS
Authors: Copple Christina , Robertson Ian D. , Thrall Donald E. , Samei Ehsan
Published: March 2013

It is important to optimize digital radiographic technique settings for small animal imaging in order to maximize image quality while minimizing radiation exposure to personnel. The purpose of this study was to evaluate two objective methods for determining optimal kVp values for an indirect flat panel digital detector. One method considered both image quality and personnel exposure as endpoints and one considered only image quality. Phantoms simulated veterinary patients of varying thicknesses with lesions of varying sizes. Phantoms were exposed to a range of kVp values (60, 81, 100, and 121), using different mAs settings for each phantom. Additionally, all phantoms were exposed to a standard test exposure of 100 kVp/2.5 mAs. Scattered radiation was recorded and used as a measure of personnel exposure. When personnel exposure was considered, a figure of merit was calculated as an endpoint of optimization. The optimal kVp value for each phantom was determined based on the highest signal difference‐to‐noise ratio with or without inclusion of the figure of merit. When personnel exposure was not considered, increasing kVp resulted in higher signal difference‐to‐noise ratios and personnel exposure increased when both patient thickness and kVp increased. Findings indicated that a single standard technique of 100 kVp/2.5 mAs was only optimal for most medium‐sized patients. Images of thinner patients should be made with a lower kVp. Very large patients require a higher kVp than 100 regardless of the optimization method used. Personnel exposure from optimized techniques was low and not expected to exceed annual occupational dose limits.
EFFECT OF SEVOFLURANE ANESTHESIA AND BLOOD DONATION ON THE SONOGRAPHIC APPEARANCE OF THE SPLEEN IN 60 HEALTHY CATS
Authors: Reese Shona L. , Zekas Lisa J. , Iazbik M. Cristina , Lehman Amy , Couto C. Guillermo
Published: March 2013

The aims of this prospective study were to describe the normal sonographic size and appearance of the feline spleen, and to test effects of sevoflurane anesthesia and blood collection on sonographic characteristics. Sonographic evaluations were performed in 60 healthy blood donor cats prior to anesthesia and blood collection (baseline), after anesthesia induction, after completion of blood collection while under anesthesia, and 7–10 days after blood collection. Transverse sonographic images of the splenic mid‐body were made. Splenic height, width, cross‐sectional area, echogenicity relative to the left renal cortex, and echotexture were recorded. Height, width, and cross‐sectional area were compared across time periods using linear‐mixed effects models.Holm's method was applied to adjust for multiplicity and control the overall Type 1 error rate at α = 0.05. Normal transverse sonographic splenic measurements (mean ± standard deviation) at baseline were: height 8.2 ± 1.4 mm; width 26.7 ± 4.4 mm; andCSA1.6 ± 0.5 cm2. While there were statistically significant differences in splenic height, width, and cross‐sectional area after sevoflurane anesthesia and/or blood collection, differences were of low magnitude. The spleen was diffusely homogenous and subjectively isoechoic or mildly hyperechoic relative to the left renal cortex. In 77% of castrated male cats, the spleen was isoechoic to the left renal cortex. We conclude that sevoflurane anesthesia and blood donation do not subjectively alter splenic dimensions, echogenicity and echotexture in normal cats.
RADIOGRAPHIC FEATURES OF PRIMARY AND CONCOMITANT FLEXOR ENTHESOPATHY IN THE CANINE ELBOW
Authors: de Bakker Evelien , Saunders Jimmy H. , van Bree Henri , Gielen Ingrid , Van Ryssen Bernadette
Published: March 2013

Primary flexor enthesopathy is a recently recognized elbow disorder and should be considered in the differential diagnosis of elbow lameness. For treatment planning purposes, it is important to make a distinction between primary and concomitant forms of the disease. The purpose of this prospective study was to compare radiographic findings for dogs with primary flexor enthesopathy (n = 17), concomitant flexor enthesopathy (n = 24), elbow dysplasia (n = 13), and normal dogs (n = 7). All dogs underwent a complete radiographic examination and each radiographic image was evaluated for the presence or absence of following characteristics: irregular medial humeral epicondyle, spur and calcified body. Additionally, the presence or absence of other elbow disorders (medial coronoid process disease, osteochondritis dissecans, ununited anconeal process, incongruity, subtrochlear sclerosis, and osteoarthritis) was recorded. Radiographic characteristics of flexor enthesopathy were found in 86% of painful joints in the primary flexor enthesopathy group and in 100% of painful joints in the concomitant flexor enthesopathy group. Radiographic characteristics of flexor enthesopathy were not found in sound elbow and elbow dysplasia groups. Frequencies and details of individual radiographic characteristics did not differ between primary and concomitant flexor enthesopathy groups. Findings support the use of radiography as a first screening method for detection of flexor enthesopathy, but not as a technique for distinguishing primary vs. concomitant forms.
The impact of seasonal flooding on agriculture: the spring 2012 floods in Somerset, England
Authors: Morris J. , Brewin P.
Published: March 2013

Exceptional rainfall in spring 2012 caused widespread flooding and damage to agricultural grasslands in Somerset in south western England, much of them farmed under agri‐environment agreements. The seasonal timing of the flood and its relatively long duration (in excess of 4 weeks in some areas) led to a serious loss of grazing and winter feed in 2012. A survey of farmers, combined with the development of a framework to estimate the impact of seasonal flooding, identified the effects on farm businesses and the ways that farmers coped. Impacts on agri‐environment outcomes were valued at the cost of funding stewardship schemes. The methods and estimates can help inform strategies to deal with changes in flood risk in areas of agricultural and environmental interest, whether induced by changes in catchment land use or climate.
Sarcoidosis and Sjögren's syndrome: clinical and salivary evaluation
Authors: Mansour Mohammed J. , He Cixin , Al‐Farra Sharif T. , Khuder Sadik A. , Wright John M. , Kessler Harvey P. , Hinton Robert J. , Al‐Hashimi Ibtisam
Published: March 2013

Background

Sarcoidosis and Sjögren's syndrome are two different diseases; however, when affecting the salivary glands, both diseases exhibit similar clinical signs and symptoms, which often complicates the diagnosis. The purpose of this study was to investigate the possibility of using salivary electrophoresis to differentiate between the two diseases.

Methods

Saliva was collected from patients with sarcoidosis and patients with Sjögren's syndrome. Salivary flow rate, total protein, and electrophoretic profiles were examined.

Results

Mean salivary flow rate was 0.41 ± 0.07 ml/min/gland vs. 0.43 ± 0.07 ml/min/gland; total salivary protein was 130.0 ± 29.2 mg% vs. 104.0 ± 8.8 mg% for sarcoidosis vs. Sjögren's syndrome, respectively. No differences were observed in salivary flow rate, total salivary protein, or electrophoretic profile between patients with sarcoidosis and patients with Sjögren's syndrome (P = 0.768, 0.718, and 1.000, respectively).

Conclusions

Salivary protein electrophoresis does not appear to be useful to differentiate between sarcoidosis and Sjögren's syndrome.
A Markov‐Based Road Maintenance Optimization Model Considering User Costs
Authors: Gao Hui , Zhang Xueqing
Published: March 2013

User costs of different maintenance actions need to be assessed in road maintenance as well as the maintenance costs. The vehicle operating cost (VOC) and the travel delay cost are two major components of the user costs associated with road maintenance actions. This article simplifies the general calculation models of these two user cost components and develops a multiobjective Markov‐based model to minimize both maintenance cost and user cost subject to a number of constraints including the average annual budget limit and the performance requirement. The road deterioration process is modeled as a discrete‐time Markov process, the states of road performance are defined in terms of the road roughness, and the state transition probabilities are estimated considering the effects of deterioration and maintenance actions. An example is provided to illustrate the use of the proposed road maintenance optimization model. The results show that the optimal road maintenance plan obtained from the model is practical to implement and is cost‐effective compared with the periodical road maintenance plan. The results also indicate that the maintenance cost and the user cost are competitive. When maintenance works are carried out more frequently, the life‐cycle maintenance costs will increase while the life‐cycle user costs will decrease. This is because the VOC contributes the most amount of the user cost and its change has a contrary trend to the change of the maintenance cost over time.
An ERBB3/ERBB2 oncogenic unit plays a key role in NRG1 signaling and melanoma cell growth and survival
Authors: Zhang Keman , Wong Poki , Duan Jiaqi , Jacobs Barbara , Borden Ernest C. , Bedogni Barbara
Published: March 2013

We recently identified neuregulin‐1 (NRG1) as a novel target of Notch1 required in Notch‐dependent melanoma growth. ERBB3 and ERBB4, tyrosine kinase receptors specifically activated by NRG1, have been shown to be either elevated in melanoma cell lines and tumors or to be mutated in 20% of melanomas, respectively. While these data support key roles of NRG1 and its receptors in the pathogenesis of melanoma, whether ERBB3 and ERBB4 display redundant or exclusive functions is not known. Here, we show that ERBB3 and ERBB4 inhibition results in distinct outcomes. ERBB3 inhibition ablates the cellular responses to NRG1, results in AKT inactivation and leads to cell growth arrest and apoptotic cell death. In contrast, ERBB4 knockdown mildly affects cell growth, has no effects on cell survival and, importantly, does not alter the responses to NRG1. Finally, we identified ERBB2 as a key coreceptor in NRG1‐dependent ERBB3 signaling. ERBB2 forms a complex with ERBB3, and its inhibition recapitulates the phenotypes observed upon ERBB3 ablation. We propose that an NRG1‐ERBB3‐ERBB2 signaling unit operates in melanoma cells where it promotes growth and survival.
Regulation of nitrate reduction in Arabidopsis WT and hxk1 mutant under C and N metabolites
Authors: Reda Małgorzata
Published: March 2013

As in plants sugar sensing and signal transduction involve pathways dependent or independent on hexokinase 1 (HXK1) as a glucose sensor, research was conducted to determine which pathway is responsible for regulation of the nitrate reduction. An Arabidopsis mutant with T‐DNA insertion in the AtHXK1 gene and defects in glucose signaling (hxk1) was used to determine nitrate reductase (NR) activity, NIA genes expression in leaves after 8‐h treatment with sugars (glucose and sucrose), organic acids [2‐oxoglutarate (2OG)] and amino acids (glutamine and glutamate). Sugars, especially sucrose, caused induction of NR actual activity accompanied by an increase of the NR activation state, indicating the posttranslational nature of the modifications. Those modifications were observed in wild‐type (WT) and hxk1 leaves, suggesting that regulation of NR activity by sugars does not involve HXK1 as a glucose sensor. Moreover, sugars enhanced expression of NIA genes. However, a higher level of NIA transcripts did not lead to an increase of total NR activity in sugar‐treated plants. This may suggest that posttranslational modification of NR is fundamental regulatory mechanisms controlling NR activity in response to C metabolites. Treatment of plants with 2‐OG also modified NR through the posttranslational modifications. Elevation of actual NR activity and the enzyme activation state in WT and hxk1 leaves was observed. Amino acids caused a decrease of NIA gene expression and NR activities in WT and hxk1 leaves indicating that mutation in the hexokinase‐dependent glucose signaling pathway did not interrupt the amino acid feedback regulation of NR.
DIAGNOSTIC SENSITIVITY AND INTEROBSERVER AGREEMENT OF RADIOGRAPHY AND ULTRASONOGRAPHY FOR DETECTING TROCHLEAR RIDGE OSTEOCHONDROSIS LESIONS IN THE EQUINE STIFLE
Authors: Beccati Francesca , Chalmers Heather J. , Dante Sara , Lotto Eleonora , Pepe Marco
Published: March 2013

Osteochondrosis lesions commonly occur on the femoral trochlear ridges in horses and radiography and ultrasonography are routinely used to diagnose these lesions. However, poor correlation has been found between radiographic and arthroscopic findings of affected trochlear ridges. Interobserver agreement for ultrasonographic diagnoses and correlation between ultrasonographic and arthroscopic findings have not been previously described. Objectives of this study were to describe diagnostic sensitivity and interobserver agreement of radiography and ultrasonography for detecting and grading osteochondrosis lesions of the equine trochlear ridges, using arthroscopy as the reference standard. Twenty‐two horses were sampled. Two observers independently recorded radiographic and ultrasonographic findings without knowledge of arthroscopic findings. Imaging findings were compared between observers and with arthroscopic findings. Agreement between observers was moderate to excellent (κ 0.48–0.86) for detecting lesions using radiography and good to excellent (κ 0.74–0.87) for grading lesions using radiography. Agreement between observers was good to excellent (κ 0.78–0.94) for detecting lesions using ultrasonography and very good to excellent (κ 0.86–0.93) for grading lesions using ultrasonography. Diagnostic sensitivity was 84–88% for radiography and 100% for ultrasonography. Diagnostic specificity was 89–100% for radiography and 60–82% for ultrasonography. Agreement between radiography and arthroscopy was good (κ 0.64–0.78). Agreement between ultrasonography and arthroscopy was very good to excellent (κ 0.81–0.87). Findings from this study support ultrasound as a preferred method for predicting presence and severity of osteochondrosis lesions involving the femoral trochlear ridges in horses.
SURVIVAL TIMES FOR CANINE INTRANASAL SARCOMAS TREATED WITH RADIATION THERAPY: 86 CASES (1996–2011)
Authors: Sones Evan , Smith Annette , Schleis Stephanie , Brawner William , Almond Gregory , Taylor Kathryn , Haney Siobhan , Wypij Jackie , Keyerleber Michele , Arthur Jennifer , Hamilton Terrance , Lawrence Jessica , Gieger Tracy , Sellon Rance , Wright Zack
Published: March 2013

Sarcomas comprise approximately one‐third of canine intranasal tumors, however few veterinary studies have described survival times of dogs with histologic subtypes of sarcomas separately from other intranasal tumors. One objective of this study was to describe median survival times for dogs treated with radiation therapy for intranasal sarcomas. A second objective was to compare survival times for dogs treated with three radiation therapy protocols: daily‐fractionated radiation therapy;Monday,Wednesday, andFriday fractionated radiation therapy; and palliative radiation therapy. Medical records were retrospectively reviewed for dogs that had been treated with radiation therapy for confirmed intranasal sarcoma. A total of 86 dogs met inclusion criteria. Overall median survival time for included dogs was 444 days. Median survival time for dogs with chondrosarcoma (n= 42) was 463 days, fibrosarcoma (n= 12) 379 days, osteosarcoma (n= 6) 624 days, and undifferentiated sarcoma (n= 22) 344 days. Dogs treated with daily‐fractionated radiation therapy protocols;Monday,Wednesday andFriday fractionated radiation therapy protocols; and palliative radiation therapy protocols had median survival times of 641, 347, and 305 days, respectively. A significant difference in survival time was found for dogs receiving curative intent radiation therapy vs. palliative radiation therapy (P= 0.032). A significant difference in survival time was also found for dogs receiving daily‐fractionated radiation therapy vs.Monday,Wednesday andFriday fractionated radiation therapy (P= 0.0134). Findings from this study support the use of curative intent radiation therapy for dogs with intranasal sarcoma. Future prospective, randomized trials are needed for confirmation of treatment benefits.
IMAGING DIAGNOSIS—MALIGNANT PERIPHERAL NERVE SHEATH TUMOR PRESENTING AS AN INTRA‐AXIAL BRAIN MASS IN A YOUNG DOG
Authors: Shihab Nadia , Summers Brian A. , Benigni Livia , McEvoy Andrew W. , Volk Holger A.
Published: March 2013

A 3‐year‐old Labrador retriever was presented with acute onset seizures. Magnetic resonance imaging demonstrated an intra‐axial mass affecting the right temporal lobe of the brain. Surgical resection and histopathological findings were most consistent with a malignant peripheral nerve sheath tumor. After initial recovery, deterioration 3 months post surgery prompted euthanasia. Post‐mortem revealed a mass protruding from the ventral surface of the temporal lobe, encroaching upon the optic chiasm and invading the brain. Histopathology findings were again consistent with malignant peripheral nerve sheath tumor. Although rare, this tumor should be included as a possible differential diagnosis for intra‐axial brain masses in dogs.
CORRELATIVE ULTRASOUND ANATOMY OF THE FELINE BRACHIAL PLEXUS AND MAJOR NERVES OF THE THORACIC LIMB
Authors: Ansón Agustina , Gil Francisco , Laredo Francisco G. , Soler Marta , Belda Eliseo , Ayala Maria D. , Agut Amalia
Published: March 2013

Brachial plexus avulsions commonly occur in cats due to traumatic injuries involving the shoulder. Ultrasound may be an effective method for detecting injured nerves. Additional applications may include characterization of brachial plexus neoplasms and guidance of anesthetic nerve blocks. Aims of this study were to describe ultrasonographic approaches and the normal appearance of this plexus and other major nerves of the thoracic limb in cats. Eight feline cadavers were used to determine anatomic landmarks, obtain cross‐sectional anatomic images of the target nerves, and compare these with ultrasound images. An ultrasonographic study was performed in five fresh feline cadavers to assess the brachial plexus and its major components at the levels of the axilla and proximal, middle and distal (lateral and medial approaches) humeral regions. Five healthy adult cats were recruited for an in vivo ultrasonographic study using the same protocol described for the cadaver ultrasonographic study. The roots of the brachial plexus appeared as a cluster of small, round hypoechoic structures surrounded by a hyperechoic rim in the axillary approach. The radialis, medianus, and ulnaris nerves were individually visualized on proximal and middle humeral approaches. The medianus and ulnaris nerves were easily identified on the medial aspect of the humerus in the distal approach. The superficial branch of radialis nerve was seen on the lateral aspect of the distal humerus approach. The nerves appeared as oval‐to‐round hypoechogenic structures with a hyperechogenic rim. Future studies are needed to compare findings from this study with those in cats with confirmed brachial plexus injuries or other lesions.
WHOLE BODY COMPUTED TOMOGRAPHIC CHARACTERISTICS OF SKELETAL AND CARDIAC MUSCULAR METASTATIC NEOPLASIA IN DOGS AND CATS
Authors: Vignoli Massimo , Terragni Rossella , Rossi Federica , Frühauf Lukas , Bacci Barbara , Ressel Lorenzo , Capitani Ombretta , Marconato Laura
Published: March 2013

Muscular metastatic neoplasia has been reported to be rare in domestic animals, however previous studies were based primarily on necropsy findings. The purpose of this retrospective study was to describe whole body computed tomography (CT) characteristics of confirmed muscular metastases in a cohort of dogs and cats presented for oncology evaluation. Medical records of 1201 oncology patients were reviewed. Included animals underwent pre and postcontrast whole body CT, and CT‐guided tru‐cut biopsy or fine needle aspiration of one or more metastatic lesions. Twenty‐one dogs and six cats met inclusion criteria, representing 2.08% of all canine oncology patients and 3.1% of all feline oncology patients. Mean age was 9.6 years. Postcontrast CT characteristics included well‐demarcated, oval‐to‐round lesions with varying enhancement patterns: ring enhancing (n = 16), heterogeneously enhancing (n = 8), or homogeneously enhancing (n = 5). Five animals showed concurrent and varying nodular patterns. In seven cases (five dogs and two cats), one single muscular nodule was observed. In 20 cases, two or more lesions were observed. In two cases, cardiac hypodense nodules were observed in the postcontrast CT, while appearing isodense in the precontrast study. Necropsy confirmed neoplasia in both of them. Locations of muscular metastases included epaxial/paraspinal muscles of the cervical, thoracic, and lumbar spine (n = 18), superficial muscles of the thoracic wall (n = 13), scapular/shoulder region (n = 3), hind limb (n = 3), and abdominal wall muscles (n = 1). Findings supported the use of pre and postcontrast whole body CT for oncologic staging in dogs and cats, especially for primary tumors characterized by a high metastatic rate.
COMPUTED TOMOGRAPHY OF NONANESTHETIZED CATS WITH UPPER AIRWAY OBSTRUCTION
Authors: Stadler Krystina , O'Brien Robert
Published: March 2013

Upper airway obstruction is a potentially life‐threatening problem in cats and for which a noninvasive, sensitive method rapid diagnosis is needed. The purposes of this prospective study were to describe a computed tomography (CT) technique for nonanesthetized cats with upper airway obstruction, CT characteristics of obstructive diseases, and comparisons between CT findings and findings from other diagnostic tests. Ten cats with clinical signs of upper airway obstruction were recruited for the study. Four cats with no clinical signs of upper airway obstruction were recruited as controls. All cats underwent computed tomography imaging without sedation or anesthesia, using a 16‐slice helical CT scanner and a previously described transparent positional device. Three‐dimensional (3D) internal volume rendering was performed on all CT image sets and 3D external volume rendering was also performed on cats with evidence of mass lesions. Confirmation of upper airway obstruction was based on visual laryngeal examination, endoscopy, fine‐needle aspirate, biopsy, or necropsy. Seven cats were diagnosed with intramural upper airway masses, two with laryngotracheitis, and one with laryngeal paralysis. The CT and 3D volume‐rendered images identified lesions consistent with upper airway disease in all cats. In cats with mass lesions, CT accurately identified the mass and location. Findings from this study supported the use of CT imaging as an effective technique for diagnosing upper airway obstruction in nonanesthetized cats.
COMPUTED TOMOGRAPHIC AND RADIOGRAPHIC CHARACTERISTICS OF AORTIC LESIONS IN 42 DOGS WITH SPIROCERCOSIS
Authors: Kirberger Robert M. , Stander Nerissa , Cassel Nicky , Pazzi Paolo , Mukorera Varaidzo , Christie Jevan , Carstens Ann , Dvir Eran
Published: March 2013

Spirocerca lupi is a common cause of vomiting, regurgitation, and sudden death in dogs that live in tropical or subtropical regions. Sudden death due to aortic rupture may occur with no preceding clinical signs. The purpose of this prospective study was to compare radiographic and computed tomographic (CT) characteristics of aortic lesions in a cohort of 42 dogs with endoscopically confirmed spirocercosis. Dorsoventral and right lateral recumbent thoracic radiographic findings were compared with pre‐ and postcontrast thoracic CT findings. Aortic mineralization was detected using CT in 18/42 dogs (43%). Three dogs had faint diffuse aortic wall mineralization. Using CT as the reference standard, radiographs had a sensitivity and specificity of 6% and 96%, respectively, for detecting aortic mineralization. A total of 20 aortic aneurysms were detected using CT in 15/42 dogs (36%). Using CT as the reference standard, radiographs had a sensitivity and specificity of 86% and 56%, respectively, for detecting aortic aneurysms. Respiratory motion, aortic displacement by esophageal masses and Spirocerca nodules adjacent to the aorta mimicked aneurysm formation on radiographs. Aortic thrombi were seen in two dogs in postcontrast CT images. Findings from this study indicated that aortic mineralization and aneurysm formation are common in dogs with spirocercosis. Findings also supported the use of pre‐ and postcontrast CT as effective methods for detecting and characterizing these lesions.
WHOLE‐BODY BIODISTRIBUTION OF 3′‐DEOXY‐3′‐[18F]FLUOROTHYMIDINE (18FLT) IN HEALTHY ADULT CATS
Authors: Rowe Joshua A. , Morandi Federica , Wall Jonathan S. , Akula Murthy , Kennel Stephen J. , Osborne Dustin , Martin Emily B. , Galyon Gina D. , Long Misty J. , Stuckey Alan C. , LeBlanc Amy K.
Published: March 2013

Positron emission tomography/computed tomography (PET/CT) utilizing 3′‐deoxy‐3′‐[18F]fluorothymidine (18FLT), a proliferation tracer, has been found to be a useful tool for characterizing neoplastic diseases and bone marrow function in humans. As PET and PET/CT imaging become increasingly available in veterinary medicine, knowledge of radiopharmaceutical biodistribution in veterinary species is needed for lesion interpretation in the clinical setting. The purpose of this study was to describe the normal biodistribution of 18FLT in adult domestic cats. Imaging of six healthy young adult castrated male cats was performed using a commercially available PET/CT scanner consisting of a 64‐slice helical CT scanner with an integrated whole‐body, high‐resolution lutetium oxy‐orthosilicate (LSO) PET scanner. Cats were sedated and injected intravenously with 108.60 ± 2.09 (mean ± SD) MBq of 18FLT (greater than 99% radiochemical purity by high‐performance liquid chromatography). Imaging was performed in sternal recumbency under general anesthesia. Static images utilizing multiple bed positions were acquired 80.83 ± 7.52 (mean ± SD) minutes post‐injection. Regions of interest were manually drawn over major parenchymal organs and selected areas of bone marrow and increased tracer uptake. Standardized uptake values were calculated. Notable areas of uptake included hematopoietic bone marrow, intestinal tract, and the urinary and hepatobiliary systems. No appreciable uptake was observed within brain, lung, myocardium, spleen, or skeletal muscle. Findings from this study can be used as baseline data for future studies of diseases in cats.
CLINICAL, IMAGING, AND PATHOLOGIC CHARACTERISTICS OF GURLTIA PARALYSANS MYELOPATHY IN DOMESTIC CATS FROM CHILE
Authors: Mieres Marcelo , Gómez Marcelo A. , Lillo Carla , Rojas Marcela A. , Moroni Manuel , Muñoz Pamela , Acosta‐Jamett Gerardo , Wiegand Ricardo
Published: March 2013

Gurltia paralysans is a rare metastrongylid nematode of domestic cats that is found mainly in the veins of the spinal cord subarachnoid space and parenchyma. Endemic regions for G. paralysans mainly include Chile and Argentina. The ante mortem diagnosis of gurltiosis is difficult and based primarily on neurological signs, epidemiological factors, and the exclusion of other causes of feline myelopathies. The purpose of this retrospective case series was to describe clinical, imaging, and pathologic characteristics in nine domestic cats naturally infected with G. paralysans. Imaging tests included radiography, myelography, computed tomographic myelography (myelo‐CT), and magnetic resonance imaging (MRI). Neurological signs included paraparesis, paraplegia, pelvic limb ataxia and proprioceptive deficits, pelvic limb tremors, lumbosacral hyperesthesia, and tail trembling or atony. Complete blood count findings included a decrease in the mean corpuscular hemoglobin concentration value in eight cats. Eosinophilia in peripheral blood was observed in three cats, and thrombocytopenia was observed in three cats. Cerebrospinal fluid analysis revealed mononuclear pleocytosis in five cases. Myelo‐CT showed diffuse enlargement of the spinal cord at the midthoracic, lumbar, and sacral regions in all cats. Magnetic resonance image findings in the thoracic and lumbar region demonstrated multiple small nodular areas of T2 hyperintensity in the periphery of the spinal cord parenchyma. Localized intraparenchymal areas of increased T2 intensity were also observed in the thoracolumbar spinal cord and lumbosacral conus medullaris. In conclusion, G. paralysans should be considered as a differential diagnosis for domestic cats in endemic regions that have this combination of clinical and imaging characteristics.
Kv3.1 channels stimulate adult neural precursor cell proliferation and neuronal differentiation
Authors: Yasuda Takahiro , Cuny Hartmut , Adams David J.
Published: March 2013

Key points

In the adult mammalian brain, neural precursor cells (NPCs) play an important role in neuronal plasticity.

Although adult NPCs exhibit voltage‐gated, delayed rectifier K+ (KDR) channel currents, the KDR channel subtype dominantly expressed in adult NPCs and its functional role have not been defined.

Using gene knockdown targeting Kv3.1 K+ channels, we show Kv3.1 is a dominant KDR subtype expressed in adult NPCs.

Kv3.1 knockdown significantly decreased adult NPC proliferation and reduced differentiation into neuroblasts.

Our findings provide new insight into a mechanism of adult neurogenesis and suggest that selective activation of Kv3.1 in adult NPCs may be a new therapeutic approach to treating neurodegenerative diseases.

Abstract  Adult neural stem/precursor cells (NPCs) play a pivotal role in neuronal plasticity throughout life. Among ion channels identified in adult NPCs, voltage‐gated delayed rectifier K+ (KDR) channels are dominantly expressed. However, the KDR channel subtype and its physiological role are still undefined. We used real‐time quantitative RT‐PCR and gene knockdown techniques to identify a major functional KDR channel subtype in adult NPCs. Dominant mRNA expression of Kv3.1, a high voltage‐gated KDR channel, was quantitatively confirmed. Kv3.1 gene knockdown with specific small interfering RNAs (siRNA) for Kv3.1 significantly inhibited Kv3.1 mRNA expression by 63.9% (P < 0.001) and KDR channel currents by 52.2% (P < 0.001). This indicates that Kv3.1 is the subtype responsible for producing KDR channel outward currents. Resting membrane properties, such as resting membrane potential, of NPCs were not affected by Kv3.1 expression. Kv3.1 knockdown with 300 nm siRNA inhibited NPC growth (increase in cell numbers) by 52.9% (P < 0.01). This inhibition was attributed to decreased cell proliferation, not increased cell apoptosis. We also established a convenient in vitro imaging assay system to evaluate NPC differentiation using NPCs from doublecortin‐green fluorescent protein transgenic mice. Kv3.1 knockdown also significantly reduced neuronal differentiation by 31.4% (P < 0.01). We have demonstrated that Kv3.1 is a dominant functional KDR channel subtype expressed in adult NPCs and plays key roles in NPC proliferation and neuronal lineage commitment during differentiation.
Computationally efficient parabolic equation solutions to seismo-acoustic problems involving thin or low-shear elastic layers
Authors: Metzler Adam M. , Collis Jon M.
Published: March 2013

Shallow-water environments typically include sediments containing thin or low-shear layers. Numerical treatments of these types of layers require finer depth grid spacing than is needed elsewhere in the domain. Thin layers require finer grids to fully sample effects due to elasticity within the layer. As shear wave speeds approach zero, the governing system becomes singular and fine-grid spacing becomes necessary to obtain converged solutions. In this paper, a seismo-acoustic parabolic equation solution is derived utilizing modified difference formulas using Galerkin's method to allow for variable-grid spacing in depth. Propagation results are shown for environments containing thin layers and low-shear layers.
Optimum Chemical Sites and Techniques for Searches for Negatively Charged Rare Particles
Authors: Boyd R. N. , Takahashi K. , Perry Robert J. , Miller Terry A.
Published: March 2013

Supersymmetric particle theories have predicted the existence of massive, negatively charged, nonstrongly interacting particles, denoted as X
-
particles. If stable X
-
particles existed at the onset of primordial nucleosynthesis, they would have been bound initially to the primordial nuclides. However, subsequent stellar processing, as part of the chemical evolution of the galaxy, is shown to have produced considerable rearrangement of the relative chemical abundances of X
-
particles subsequent to their binding to primordial nuclei. Optimal chemical environments in which to search for X
-
particles are found to be boron and fluorine. A mass-independent search for X
-
particles bound to heavy nuclei that utilizes laser spectroscopy of rotational bands in diatomic molecules is estimated to have an unusually high relative sensitivity to possible X
-
particles.
Optical Studies of Hydrogen Above 200 Gigapascals: Evidence for Metallization by Band Overlap
Authors: Hemley R. J. , Mao H. K.
Published: March 2013

Direct optical observations of solid hydrogen to pressures in the 250-gigapascal (2.5-megabar) range at 77 K are reported. Hydrogen samples appear nearly opaque at the maximum pressures. Measurements of absorption and Raman spectra provide evidence that electronic excitations in the visible region begin at ∼200 gigapascals. The optical data are consistent with a band-overlap mechanism of metallization.
Signaling by p38 MAPK Stimulates Nuclear Localization of the Microprocessor Component p68 for Processing of Selected Primary MicroRNAs
Authors: Hong Sungguan , Noh Hyangsoon , Chen Haoming , Padia Ravi , Pan Zhixing K. , Su Shi-Bing , Jing Qing , Ding Han-Fei , Huang Shuang
Published: March 2013

An early step in microRNA processing depends on signaling downstream of the p38 mitogen-activated protein kinase.
Extracellular DNA Shields against Aminoglycosides in Pseudomonas aeruginosa Biofilms
Authors: Chiang Wen-Chi , Nilsson Martin , Jensen Peter Østrup , Høiby Niels , Nielsen Thomas E. , Givskov Michael , Tolker-Nielsen Tim
Published: March 2013

Within recent years, it has been established that extracellular DNA is a key constituent of the matrix of microbial biofilms. In addition, it has recently been demonstrated that DNA binds positively charged antimicrobials such as aminoglycosides and antimicrobial peptides. In the present study, we provide evidence that extracellular DNA shields against aminoglycosides in
Pseudomonas aeruginosa
biofilms. We show that exogenously supplemented DNA integrates into
P. aeruginosa
biofilms and increases their tolerance toward aminoglycosides. We provide evidence that biofilms formed by a DNA release-deficient
P. aeruginosa
quorum-sensing mutant are more susceptible to aminoglycoside treatment than wild-type biofilms but become rescued from the detrimental action of aminoglycosides upon supplementation with exogenous DNA. Furthermore, we demonstrate that exposure to lysed polymorphonuclear leukocytes, which are thought to be a source of extracellular DNA at sites of infections, increases the tolerance of
P. aeruginosa
biofilms toward aminoglycosides. Although biofilm-associated aminoglycoside tolerance recently has been linked to extracellular DNA-mediated activation of the
pmr
genes, we demonstrate that the aminoglycoside tolerance mediated by the presence of extracellular DNA is not caused by activation of the
pmr
genes in our
P. aeruginosa
biofilms but rather by a protective shield effect of the extracellular DNA.
Quantifying Subpopulation Synergy for Antibiotic Combinations via Mechanism-Based Modeling and a Sequential Dosing Design
Authors: Landersdorfer Cornelia B. , Ly Neang S. , Xu Hongmei , Tsuji Brian T. , Bulitta Jürgen B.
Published: March 2013

Quantitative modeling of combination therapy can describe the effects of each antibiotic against multiple bacterial populations. Our aim was to develop an efficient experimental and modeling strategy that evaluates different synergy mechanisms using a rapidly killing peptide antibiotic (nisin) combined with amikacin or linezolid as probe drugs. Serial viable counts over 48 h were obtained in time-kill experiments with all three antibiotics in monotherapy against a methicillin-resistant
Staphylococcus aureus
USA300 strain (inoculum, 10
8
CFU/ml). A sequential design (initial dosing of 8 or 32 mg/liter nisin, switched to amikacin or linezolid at 1.5 h) assessed the rate of killing by amikacin and linezolid against nisin-intermediate and nisin-resistant populations. Simultaneous combinations were additionally studied and all viable count profiles comodeled in S-ADAPT and NONMEM. A mechanism-based model with six populations (three for nisin times two for amikacin) yielded unbiased and precise (
r
= 0.99, slope = 1.00; S-ADAPT) individual fits. The second-order killing rate constants for nisin against the three populations were 5.67, 0.0664, and 0.00691 liter/(mg · h). For amikacin, the maximum killing rate constants were 10.1 h
−1
against its susceptible and 0.771 h
−1
against its less-susceptible populations, with 14.7 mg/liter amikacin causing half-maximal killing. After incorporating the effects of nisin and amikacin against each population, no additional synergy function was needed. Linezolid inhibited successful bacterial replication but did not efficiently kill populations less susceptible to nisin. Nisin plus amikacin achieved subpopulation synergy. The proposed sequential and simultaneous dosing design offers an efficient approach to quantitatively characterize antibiotic synergy over time and prospectively evaluate antibiotic combination dosing strategies.
Introduction of a Lysine Residue Promotes Aggregation of Temporin L in Lipopolysaccharides and Augmentation of Its Antiendotoxin Property
Authors: Srivastava Saurabh , Ghosh Jimut Kanti
Published: March 2013

Temporin L (TempL) is a 13-residue frog antimicrobial peptide that shows moderate bactericidal activity and antiendotoxin properties in macrophages. We envisioned that, due to its very hydrophobic nature, the peptide might fail to show its desired biological properties. It was predicted by employing the available algorithms that the replacement of a glutamine by lysine at position 3 could appreciably reduce its aggregation propensity in an aqueous environment. In order to investigate the structural, functional, and biological consequences of replacement of glutamine by lysine at its third position, TempL and the corresponding analog, Q3K-TempL, was synthesized and characterized. Introduction of the lysine residue significantly promoted the self-assembly and oligomeric state of TempL in lipopolysaccharide (LPS). Q3K-TempL exhibited augmented binding to LPS and also dissociated LPS aggregates with greater efficacy than TempL. Further, Q3K-TempL inhibited the LPS-induced proinflammatory cytokines in rat primary macrophages
in vitro
and
in vivo
in BALB/c mice with greater efficacy than TempL. The results showed that a simple amino acid substitution in a short hydrophobic antimicrobial peptide, TempL, enhanced its antiendotoxin properties and illustrate a plausible correlation between its aggregation properties in LPS and LPS detoxification activity.
Identification and Evaluation of Novel Acetolactate Synthase Inhibitors as Antifungal Agents
Authors: Richie Daryl L. , Thompson Katherine V. , Studer Christian , Prindle Vivian C. , Aust Thomas , Riedl Ralph , Estoppey David , Tao Jianshi , Sexton Jessica A. , Zabawa Thomas , Drumm Joseph , Cotesta Simona , Eichenberger Jürg , Schuierer Sven , Hartmann Nicole , Movva N. Rao , Tallarico John A. , Ryder Neil S. , Hoepfner Dominic
Published: March 2013

High-throughput phenotypic screening against the yeast
Saccharomyces cerevisiae
revealed a series of triazolopyrimidine-sulfonamide compounds with broad-spectrum antifungal activity, no significant cytotoxicity, and low protein binding. To elucidate the target of this series, we have applied a chemogenomic profiling approach using the
S. cerevisiae
deletion collection. All compounds of the series yielded highly similar profiles that suggested acetolactate synthase (Ilv2p, which catalyzes the first common step in branched-chain amino acid biosynthesis) as a possible target. The high correlation with profiles of known Ilv2p inhibitors like chlorimuron-ethyl provided further evidence for a similar mechanism of action. Genome-wide mutagenesis in
S. cerevisiae
identified 13 resistant clones with 3 different mutations in the catalytic subunit of acetolactate synthase that also conferred cross-resistance to established Ilv2p inhibitors. Mapping of the mutations into the published Ilv2p crystal structure outlined the chlorimuron-ethyl binding cavity, and it was possible to dock the triazolopyrimidine-sulfonamide compound into this pocket
in silico
. However, fungal growth inhibition could be bypassed through supplementation with exogenous branched-chain amino acids or by the addition of serum to the medium in all of the fungal organisms tested except for
Aspergillus fumigatus
. Thus, these data support the identification of the triazolopyrimidine-sulfonamide compounds as inhibitors of acetolactate synthase but suggest that targeting may be compromised due to the possibility of nutrient bypass
in vivo
.