bluuebunny/crossref_metadata_2025_split huggingface dataset:
Efficient Differentiation of Hepatocytes from Human Embryonic Stem Cells Exhibiting Markers Recapitulating Liver Development In Vivo
Authors: Hay David C. , Zhao Debiao , Fletcher Judy , Hewitt Zoë A. , McLean Doris , Urruticoechea-Uriguen Alai , Black James R. , Elcombe Cliff , Ross James A. , Wolf Roland , Cui Wei 
Published: February 2008

Abstract
The potential to differentiate human embryonic stem cells (hESCs) in vitro to provide an unlimited source of human hepatocytes for use in biomedical research, drug discovery, and the treatment of liver diseases holds great promise. Here we describe a three-stage process for the efficient and reproducible differentiation of hESCs to hepatocytes by priming hESCs towards definitive endoderm with activin A and sodium butyrate prior to further differentiation to hepatocytes with dimethyl sulfoxide, followed by maturation with hepatocyte growth factor and oncostatin M. We have demonstrated that differentiation of hESCs in this process recapitulates liver development in vivo: following initial differentiation, hESCs transiently express characteristic markers of the primitive streak mesendoderm before turning to the markers of the definitive endoderm; with further differentiation, expression of hepatocyte progenitor cell markers and mature hepatocyte markers emerged sequentially. Furthermore, we have provided evidence that the hESC-derived hepatocytes are able to carry out a range of hepatocyte functions: storage of glycogen, and generation and secretion of plasma proteins. More importantly, the hESC-derived hepatocytes express several members of cytochrome P450 isozymes, and these P450 isozymes are capable of converting the substrates to metabolites and respond to the chemical stimulation. Our results have provided evidence that hESCs can be differentiated efficiently in vitro to functional hepatocytes, which may be useful as an in vitro system for toxicity screening in drug discovery.
Disclosure of potential conflicts of interest is found at the end of this article.
Legionnaires' disease: evaluation of a quantitative microbial risk assessment model
Authors: Armstrong Thomas W. , Haas Charles N. 
Published: February 2008

Background: The quantities of Legionella vary considerably from natural waters to water in contaminated domestic hot water supplies, whirlpool spas and cooling towers, with the risk for LD rising as the Legionella counts grow. We currently report the results from our Quantitative Microbial Risk Assessment (QMRA) model evaluation. We developed the LD QMRA model to better understand Legionella exposure risks.
Methods: Using an animal data derived model for LD, we calculated risks from estimated exposures for a whirlpool spa outbreak, two hot spring spa outbreaks and compared the results to the reported LD risks.
Results: The QMRA model shows agreement (generally less than an order of magnitude discrepancy) with the reported Legionnaires' disease sub-clinical severity infection, clinical severity infection, and mortality risks.
Conclusions: The LD QMRA model may lead to risk based limits to supplement the current guidance on Legionella control in cooling towers, whirlpool spas and other potential exposure sources. The verification of QMRA for LD also suggests the techniques, given suitable animal model data, may be useful in quantifying human response to other airborne pathogens.
Effectiveness of administration of phenylbutazone alone or concurrent administration of phenylbutazone and flunixin meglumine to alleviate lameness in horses
Authors: Keegan Kevin G. , Messer Nat T. , Reed Shannon K. , Wilson David A. , Kramer Joanne 
Published: February 2008

Abstract
Objective—To determine the effectiveness of administering multiple doses of phenylbutazone alone or a combination of phenylbutazone and flunixin meglumine to alleviate lameness in horses.
Animals—29 adult horses with naturally occurring forelimb and hind limb lameness.
Procedures—Lameness evaluations were performed by use of kinematic evaluation while horses were trotting on a treadmill. Lameness evaluations were performed before and 12 hours after administration of 2 nonsteroidal anti-inflammatory drug (NSAID) treatment regimens. Phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days, or phenylbutazone paste was administered at approximately 2.2 mg/kg, PO, every 12 hours for 5 days in combination with flunixin meglumine administered at 1.1 mg/kg, IV, every 12 hours for 5 days.
Results—Alleviation of lameness was greater after administration of the combination of NSAIDs than after oral administration of phenylbutazone alone. Improvement in horses after a combination of NSAIDs did not completely mask lameness. Five horses did not improve after either NSAID treatment regimen. All posttreatment plasma concentrations of NSAIDs were less than those currently allowed by the United States Equestrian Federation Inc for a single NSAID. One horse administered the combination NSAID regimen died of acute necrotizing colitis during the study.
Conclusions and Clinical Relevance—Administration of a combination of NSAIDs at the dosages and intervals used in the study reported here alleviated the lameness condition more effectively than did oral administration of phenylbutazone alone. This may attract use of combinations of NSAIDs to increase performance despite potential toxic adverse effects.
Effects of acepromazine and butorphanol on tiletamine-zolazepam anesthesia in llamas
Authors: Prado Tulio M. , Doherty Tom J. , Boggan Elizabeth B. , Airasmaa Hanna M. , Martin-Jimenez Tomas , Rohrbach Barton W. 
Published: February 2008

Abstract
Objective—To evaluate sedative, antinociceptive, and physiologic effects of acepromazine and butorphanol during tiletamine-zolazepam (TZ) anesthesia in llamas.
Animals—5 young adult llamas.
Procedures—Llamas received each of 5 treatments IM (1-week intervals): A (acepromazine, 0.05 mg/kg), B1 (butorphanol, 0.1 mg/kg), AB (acepromazine, 0.05 mg/kg, and butorphanol, 0.1 mg/kg), B2 (butorphanol, 0.2 mg/kg), or C (saline [0.9% NaCl] solution). Sedation was evaluated during a 30-minute period prior to anesthesia with TZ (2 mg/kg, IM). Anesthesia and recovery characteristics and selected cardiorespiratory variables were recorded at intervals. Antinociception was assessed via a toe-clamp technique.
Results—Sedation was not evident following any treatment. Times to sternal and lateral recumbency did not differ among treatments. Duration of lateral recumbency was significantly longer for treatment AB than for treatment C. Duration of antinociception was significantly longer for treatments A and AB, compared with treatment C, and longer for treatment AB, compared with treatment B2. Treatment B1 resulted in a significant decrease in respiratory rate, compared with treatment C. Compared with treatment C, diastolic and mean blood pressures were lower after treatment A. Heart rate was increased with treatment A, compared with treatment B1 or treatment C. Although severe hypoxemia developed in llamas anesthetized with TZ alone and with each treatment-TZ combination, hemoglobin saturation remained high and the hypoxemia was not considered clinically important.
Conclusions and Clinical Relevance—Sedation or changes in heart and respiratory rates were not detected with any treatment before administration of TZ. Acepromazine alone and acepromazine with butorphanol (0.1 mg/kg) prolonged the duration of antinociception in TZ-treated llamas.
Plasma fatty acid concentrations in Boxers and Doberman Pinschers
Authors: Smith Caren E. , Freeman Lisa M. , Meurs Kathryn M. , Rush John E. , Lamb Allison 
Published: February 2008

Abstract
Objective—To compare plasma fatty acid concentrations and the relationships of fatty acids to arrhythmias in Boxers versus Doberman Pinschers.
Animals—38 Boxers and 13 Doberman Pinschers.
Procedures—Boxers and Doberman Pinschers evaluated via Holter recording and for which a blood sample was available were included. Echocardiograms were performed in 49 of 51 dogs. The number of ventricular premature complexes (VPCs)/24 h was counted and fatty acids analyzed. Plasma fatty acid concentrations and VPCs/24 h, as well as correlations between the 2 variables, were compared between the 2 breeds.
Results—Compared with the Doberman Pinschers, Boxers had significantly higher plasma concentrations of γ-linolenic acid but lower concentrations of arachidonic acid. Total n-6 fatty acids and total polyunsaturated fatty acid concentrations were higher in Doberman Pinschers. There were significant, but weak, positive correlations between VPCs and oleic acid, total n-3 fatty acids, and total n-9 fatty acids in Boxers but not in Doberman Pinschers.
Conclusions and Clinical Relevance—Data suggested that plasma fatty acid concentrations may differ between Boxers and Doberman Pinschers and that the relationship between fatty acid concentrations and VPCs may be different between these 2 breeds.
Roles of thromboxane A2 and 5-hydroxytryptamine in endotoxin-induced digital vasoconstriction in horses
Authors: Menzies-Gow Nicola J. , Sepulveda M. Fernanda , Bailey Simon R. , Cunningham Fiona M. , Elliott Jonathan 
Published: February 2008

Abstract
Objective—To evaluate the roles of 5-hydroxytryptamine (5-HT), thromboxane A2 (T×A2), and platelet-activating factor (PAF) in endotoxin-induced digital hypoperfusion in horses.
Animals—6 healthy adult Thoroughbreds.
Procedures—Horses were treated with IV administration of saline (0.9% NaCl) solution (control treatment) or the 5-HT1B/D selective antagonist, GR55562 (0.3 mg/kg), prior to tryptamine infusion (1.6 μg/kg/min for 30 minutes) to establish an effective GR55562 dose. In a crossover study, horses were treated with IV administration of saline solution (control treatment), aspirin (4 mg/kg, 2 hours or 4 days before lipopolysaccharide [LPS] infusion), GR55562 (0.3 mg/kg), the PAF antagonist WEB2086 (3 mg/kg), or aspirin plus GR55562 prior to LPS infusion (30 ng/kg for 30 minutes). Digital blood flow was measured by use of Doppler ultrasonography. Concomitant measurements of hoof wall and coronary band surface temperatures were made. Serial blood samples were collected and plasma 5-HT and T×A2 concentrations determined.
Results—GR55562 abolished tryptamine-induced digital hypoperfusion. Neither WEB2086 nor GR55562 affected LPS-induced alterations in digital perfusion or plasma mediator concentrations. Aspirin given 2 hours before LPS administration abolished the increase in plasma T×A2 concentration and significantly attenuated LPS-induced digital hypoperfusion. Aspirin given 4 days before LPS significantly attenuated the increase in plasma T×A2 concentration and digital hypothermia. Aspirin plus GR55562 had a greater effect on LPS-induced digital hypothermia than aspirin alone.
Conclusions and Clinical Relevance—Thromboxane A2 and 5-HT played a role in mediating LPS-induced digital hypoperfusion in horses. Platelet-activating factor appeared unimportant in mediating LPS-induced 5-HT or T×A2 release or digital hypoperfusion.
Adsorptive effects of di-tri-octahedral smectite on Clostridium perfringens alpha, beta, and beta-2 exotoxins and equine colostral antibodies
Authors: Lawler Jacquelin Boggs , Hassel Diana M. , Magnuson Roberta J. , Hill Ashley E. , McCue Patrick M. , Traub-Dargatz Josie L. 
Published: February 2008

Abstract
Objective—To determine the adsorptive capability of di-tri-octahedral smectite (DTOS) on Clostridium perfringens alpha, beta, and beta-2 exotoxins and equine colostral antibodies.
Sample Population—3 C perfringens exotoxins and 9 colostral samples.
Procedures—Alpha, beta, and beta-2 exotoxins were individually co-incubated with serial dilutions of DTOS or bismuth subsalicylate, and the amount of toxin remaining after incubation was determined via toxin-specific ELISAs. Colostral samples from healthy mares were individually co-incubated with serial dilutions of DTOS, and colostral IgG concentrations were determined via single radial immunodiffusion assay.
Results—Di-tri-octahedral smectite decreased the amount of each C perfringens exotoxin in co-incubated samples in a dose-dependent manner and was more effective than bismuth subsalicylate at reducing exotoxins in vitro. Decreases in the concentration of IgG were detected in samples of colostrum that were combined with DTOS at 1:4 through 1:16 dilutions, whereas no significant decrease was evident with DTOS at the 1:32 dilution.
Conclusions and Clinical Relevance—Di-tri-octahedral smectite effectively adsorbed C perfringens exotoxins in vitro and had a dose-dependent effect on the availability of equine colostral antibodies. Results suggested that DTOS may be an appropriate adjunctive treatment in the management of neonatal clostridiosis in horses. In vivo studies are necessary to fully assess the clinical efficacy of DTOS treatment.
F-wave conduction velocity, persistence, and amplitude for the tibial nerve in clinically normal cats
Authors: Okuno Seiichi , Kobayashi Takayuki , Orito Kensuke 
Published: February 2008

Abstract
Objective—To establish a method of F-wave evaluation and to determine normative values of F-wave parameters, including F-wave conduction velocity, persistence, and amplitude for the tibial nerve in cats.
Animals—30 clinically normal cats.
Procedures—F-waves elicited in the interosseous muscles by stimulation of the tibial nerve were recorded, and linear regression analyses of the shortest latency versus the length of the tibial nerve and the limb length were performed. F-wave persistence was calculated by dividing the number of recorded F-waves by the number of stimuli.
Results—The correlation coefficient between F-wave latency and nerve length was 0.92, and that between F-wave latency and limb length was 0.58. Mean ± SD F-wave conduction velocity of the tibial nerve was calculated to be 97.1 ± 5.0 m/s. Linear regression analysis yielded the regression equation as follows: F-wave latency (milliseconds) = 2.60 + (0.02 × nerve length [mm]). Mean F-wave persistence and amplitude were 98.7 ± 2.3% and 1.01 ± 0.62 mV, respectively.
Conclusions and Clinical Relevance—Results indicated that nerve length should be used for nerve conduction studies of F-waves in felids. The regression equation for F-wave latency, conduction velocity, persistence, and amplitude may contribute to the diagnosis of nervous system diseases or injury in cats, such as trauma to the spinal cord or diabetic neuropathy.
Comparison of the distribution of glial fibrillary acidic protein, heat shock protein 60, and hypoxia-inducible factor-1α in retinas from glaucomatous and normal canine eyes
Authors: Savagian Caitlin A. , Dubielzig Richard R. , Nork T. Michael 
Published: February 2008

Abstract
Objective—To determine the effect of acute (clinical history of glaucoma for ≤ 2 days) and chronic (clinical history of glaucoma for 7 days) goniodysgenesis-related glaucoma on various stress-inducible proteins in canine retinas.
Sample Population—15 canine retinas (5 from control eyes, 5 from eyes with acute glaucoma, and 5 from eyes with chronic glaucoma).
Procedures—Globes were obtained from the Comparative Ocular Pathology Laboratory of Wisconsin. Eyes were characterized on the basis of clinical history. The distribution of glial fibrillary acidic protein (GFAP), heat shock protein (HSP) 60, and hypoxia-inducible factor (HIF)-1α was determined by use of immunohistochemical analysis.
Results—Intensity of GFAP staining increased with temporal progression of glaucoma. In specimens from eyes with acute glaucoma, staining for HSP 60 was more variable among eyes, compared with that of the control eyes, whereas specimens from eyes with chronic glaucoma typically had less HSP 60 staining than was evident in the control eyes. Neither the control eyes nor specimens from the eyes with acute glaucoma had nuclear staining for HIF-1α in the retinas. Four of 5 specimens from eyes with chronic glaucoma had nuclear staining for HIF-1α in cells of the outer nuclear layer. Staining for HIF-1α was distributed segmentally in regions of more severe atrophy and disorganization.
Conclusions and Clinical Relevance—Results of the study reported here supported a clinically evident, rapidly progressive disease with a shift in cell regulation between acute and chronic glaucoma and also supported ischemia as a mechanism of retinal injury in this disease.
Effects of ultraviolet radiation on plasma 25-hydroxyvitamin D3 concentrations in corn snakes (Elaphe guttata)
Authors: Acierno Mark J. , Mitchell Mark A. , Zachariah Trevor T. , Roundtree Marlana K. , Kirchgessner Megan S. , Sanchez-Migallon Guzman David 
Published: February 2008

Abstract
Objective—To determine whether corn snakes exposed to UVB radiation have increased plasma 25-hydroxyvitamin D3 concentrations, compared with control snakes.
Animals—12 corn snakes (Elaphe guttata).
Procedures—After an acclimation period in individual enclosures, a blood sample was collected from each snake for assessment of plasma 25-hydroxyvitamin D3 concentration. Six snakes were provided with no supplemental lighting, and 6 snakes were exposed to light from 2 full-spectrum coil bulbs. By use of a radiometer-photometer, the UVA and UVB radiation generated by the bulbs were measured in each light-treated enclosure at 3 positions at the basking surface and at 2.54 cm (1 inch) below each bulb surface; the arithmetic mean values for the 3 positions at the basking surface and each individual bulb surface were calculated immediately after the start of the study and at weekly intervals thereafter. At the end of the study (day 28), another blood sample was collected from each snake to determine plasma 25-hydroxyvitamin D3 concentration.
Results—Mean ± SD plasma concentration of 25-hydroxyvitamin D3 in snakes that were provided with supplemental lighting (196 ± 16.73 nmol/L) differed significantly from the value in control snakes (57.17 ± 15.28 nmol/L). Mean exposure to UVA or UVB did not alter during the 4-week study period, although the amount of UVA recorded near the bulb surfaces did change significantly.
Clinical Relevance—These findings have provided important insight into the appropriate UV radiation requirements for corn snakes. Further investigation will be needed before exact husbandry requirements can be determined.
Pituitary-dependent hyperadrenocorticism in a cockatoo
Authors: Starkey Simon R. , Morrisey James K. , Stewart Jennifer E. , Buckles Elizabeth L. 
Published: February 2008

Abstract
Case Description—A 13-year-old female intact Moluccan cockatoo (Cacatua moluccensis) was evaluated because of coelomic distention, presumed to be secondary to an abdominal hernia. The patient also had a history of rapid weight gain and polyuria and polydipsia.
Clinical Findings—Ultrasonography was used to confirm the existence of a pseudohernia that appeared to contain the small intestines, pancreas, and reproductive tract. Results of plasma biochemical analysis revealed hyperglycemia, hypophosphatemia, and high nonfasting bile acid concentrations and aspartate aminotransferase activity. A CBC revealed a relative heterophilia with a concomitant lymphopenia and mild monocytosis. Histologic evaluation of a liver biopsy specimen indicated chronic hepatic lipidosis. Despite a strong clinical suspicion of hyperadrenocorticism, ACTH stimulation test results were equivocal.
Treatment and Outcome—The pseudohernia was strengthened with a prolene mesh. Despite ongoing medical and surgical care, the patient developed complications associated with the herniorrhaphy and was euthanatized. The clinical suspicion of hyperadrenocorticism was confirmed on the basis of histologic evaluation of the pituitary gland by use of special stains.
Clinical Relevance—To our knowledge, pituitary-dependent hyperadrenocorticism has not been previously confirmed in Psittaciformes. The condition should be considered in birds with clinical signs consistent with those observed in mammals. For the cockatoo of this report, ACTH stimulation test results were equivocal and additional diagnostic tests should be developed for avian patients.
Magnetic resonance imaging and marsupialization of a hemorrhagic intramedullary vascular anomaly in the cervical portion of the spinal cord of a dog
Authors: Alexander Kate , Huneault Louis , Foster Robert , d'Anjou Marc-André 
Published: February 2008

Abstract
Case Description—A 1-year-old female spayed Labrador Retriever was admitted for evaluation of a progressive gait disturbance characterized by tetraparesis and general proprioceptive ataxia in all limbs.
Clinical Findings—Neurologic examination suggested a dysfunction of the C6-T2 spinal cord segments, which was slightly worse on the right side. Discomfort was suspected upon lateral flexion of the neck. Two magnetic resonance imaging (MRI) examinations at a 3-week interval revealed an intramedullary fluid-filled cavitary lesion adjacent to C7, containing a blood clot.
Treatment and Outcome—Following unsuccessful initial conservative management, surgical marsupialization of the lesion was performed through a dorsal laminectomy, durotomy, and myelotomy at C6 and C7. Histologic evaluation including immunohistochemistry was diagnostic for a vascular anomaly. Initially, the dog was nonambulatory with tetraparesis and became tetraplegic after surgery; movement was regained 6 days later. Four weeks after the procedure, the dog was able to walk unassisted. One year after surgery, the dog was actively running and jumping, with mild residual ataxia in the pelvic limbs.
Clinical Relevance—The intramedullary vascular anomaly in this dog was successfully treated with a surgical marsupialization technique. The combination of MRI, histologic eval-uation, and immunohistochemistry enabled lesion localization, evaluation of cavity content, and final diagnosis.
Problème d'accès ou déficit de stockage ? Apport du niveau de complexité de la tâche à l'étude des troubles sémantiques lors du vieillissement pathologique : le cas de la maladie d'Alzheimer
Authors: Duarte Liliana Rico , Syssau Arielle , Jiménez Manuel , Launay Michel , Terrier Patrice 
Published: February 2008

ABSTRACTThis study investigates three principal aspects of semantic memory processing in Alzheimer's disease: word finding, knowledge of the specific and generic attributes of concepts. Semantic memory is assessed by a range of verbal and visual tasks differentiated according to their level of complexity. Our hypothesis is that the processing of these types of information is modulated by the degree of effortful processing required by the tasks. The AD patients show more important difficulties on the tasks of high level of complexity. Nevertheless, although their performances improve when the level of complexity decreases, they significantly remain lower than those of the normal older subjects. These results are discussed with regard to the models of semantic memory, with particular reference to the debate in terms of a deficit of access or storage of this system in Alzheimer disease.