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61.
Yeung T Terebiznik M Yu L Silvius J Abidi WM Philips M Levine T Kapus A Grinstein S 《Science (New York, N.Y.)》2006,313(5785):347-351
The surface potential of biological membranes varies according to their lipid composition. We devised genetically encoded probes to assess surface potential in intact cells. These probes revealed marked, localized alterations in the charge of the inner surface of the plasma membrane of macrophages during the course of phagocytosis. Hydrolysis of phosphoinositides and displacement of phosphatidylserine accounted for the change in surface potential at the phagosomal cup. Signaling molecules such as K-Ras, Rac1, and c-Src that are targeted to the membrane by electrostatic interactions were rapidly released from membrane subdomains where the surface charge was altered by lipid remodeling during phagocytosis. 相似文献
62.
Loharikar A Briere E Schwensohn C Weninger S Wagendorf J Scheftel J Garvey A Warren K Villamil E Rudroff JA Kurkjian K Levine S Colby K Morrison B May A Anderson S Daly E Marsden-Haug N Erdman MM Gomez T Rhorer A Castleman J Adams JK Theobald L Lafon P Trees E Mitchell J Sotir MJ Behravesh CB 《Zoonoses and public health》2012,59(5):347-354
Outbreaks of human salmonellosis associated with live poultry contact have been reported since 1955. Multiple Salmonella serotypes have been associated with these outbreaks, and specific outbreak strains have been repeatedly linked to single hatcheries over multiple years. During 2009, four multistate outbreaks of human Salmonella infections associated with direct and indirect exposure to live poultry purchased from mail-order hatcheries and agricultural feed stores were identified, resulting in 165 culture-confirmed cases in 30 states. This report describes the epidemiologic, environmental and laboratory investigations conducted by state and local health departments, state departments of agriculture, the U.S. Department of Agriculture (USDA), Animal and Plant Health Inspection Service (APHIS), National Poultry Improvement Plan (NPIP) and National Veterinary Services Laboratories (NVSL), and the Centers for Disease Control and Prevention (CDC). Case-patients were identified through PulseNet, the national molecular subtyping network for foodborne disease surveillance, and interviewed using the CDC standard live poultry contact questionnaire that asks about poultry-related exposures during the 7 days before illness onset. These outbreaks highlight the need to focus efforts on strategies to decrease and prevent human illness associated with live poultry contact through comprehensive interventions at the mail-order hatchery, agricultural feed store and consumer levels. Additional consumer education and interventions at mail-order hatcheries and venues where live poultry are sold, including agricultural feed stores, are necessary to prevent transmission of Salmonella from poultry to humans. 相似文献
63.
Marc KnobbeDavid Levine DVM DACVS Perry HabeckerLiberty Getman DVM DACVS Jill BeechRegina Turner VMD PhD DACT 《Journal of Equine Veterinary Science》2012
Prostatic masses were detected in two geldings that were presented to our referral hospital for evaluation of dysuria. The masses were detected during transrectal palpation and ultrasonography of the prostate gland and were further evaluated using urethral endoscopy. A 10-year-old gelding underwent intraurethral debulking of the prostatic mass. Histopathological diagnosis was prostatic cystadenoma. The mass regrew within 9 months, and the horse was euthanized due to deteriorating clinical control of urinary continence. In another case, a 12-year-old gelding was scheduled for transurethral debulking; however, the owners decided against treatment and the horse was euthanized due to progression of clinical disease. Postmortem examination revealed the prostate to be nearly completely obliterated by the mass. Histopathological diagnosis was adenocarcinoma incorporated into a spindle cell population of unknown histogenesis. To our knowledge, these represent the first reported cases of equine prostatic cystadenoma and adenocarcinoma. In both horses, referring complaint was dysuria, and identification of the prostatic mass was made on palpation and ultrasonographic examination per rectum. Treatment options for prostatic masses in horses are limited because of the difficulty of obtaining prostatic tissue via biopsy, the surgical inaccessibility of the gland, and the apparent low incidence of occurrence. We have subsequently identified prostatic masses in two additional geldings, both also presenting for dysuria. However, the exact nature of these two apparent prostatic masses has not been definitively diagnosed with histopathological examinations to date. The prostate should be evaluated in male horses presenting for dysuria. 相似文献
64.
Three factors (extent of chlorination, milling extraction rate, and particle‐size reduction) in cake‐baking functionality of Croplan 594W flour were explored using a Rapid Visco‐Analyser (RVA) and time‐lapse photography. The extent of chlorination and milling extraction rate showed dramatic effects, but postmilling to reduce flour particle size was a less significant factor. RVA results showed that starch pasting was accelerated, and both peak and set‐back viscosities were enhanced, with increasing extent of chlorination. These effects were exaggerated by the high sugar concentration relevant to cake baking, compared to the same effects in water. Cake baking with chlorinated flours, in a formulation with 50% sugar (%S) and 275 parts total solvent (TS), showed that, as the extent of chlorination increased, cake moisture content and edge height decreased. Cake center height and shape factor were curvilinear, with maxima near flour with pH 4.6. Dramatic collapse occurred for cakes baked with unchlorinated flour samples, due to delayed starch pasting, as documented by time‐lapse photography and comparison to the geometry of the final cooled cakes. Starch pasting and egg white setting occurred too early for the cakes baked with excessively chlorinated flour (pH ≤4.0), but too late for the cakes baked with unchlorinated or insufficiently chlorinated flours (pH ≥4.9), compared to the ideal starch pasting and egg white setting behavior with appropriately chlorinated flours (pH >4.0 and <4.9). Informal sensory texture evaluation showed that cake mouthfeel was related to both moisture content per se and the relationship between moisture content and cake relative humidity (%RH). Excessive flour chlorination resulted in unacceptably dry cake mouthfeel. 相似文献
65.
Amanda R. Taylor Noah D. Cohen Stephen Fletcher John F. Griffin Jonathan M. Levine 《Veterinary radiology & ultrasound》2013,54(4):332-342
The purpose of this study was to describe application and machine accuracy for a new computed tomography (CT) guided, frameless, stereotactic brain biopsy system in dogs. Heads from ten canine cadavers were secured to a bite‐plate with six attached fiducial markers and imaged using CT. Fiducialized CT images were imported into stereotactic software and spherical phantom lesions between 3.9 and 5.5 mm in diameter were created in six locations. Infrared cameras and reflective markers were used to register fiducials to the reconstructed image set. Coordinates in the X, Y, and Z planes were identified for each lesion center. Iohexol (1.5 μl of 240 mgI/ml) was injected into the center of each lesion and CT scans were repeated. Pre‐ and postinjection CT images for each cadaver were fused using the system software. Application accuracy was calculated using the center of each phantom lesion and the center of each injected contrast material location. Machine accuracy was calculated using a phantom with known distances between four fixed points in the X, Y, and Z planes. Mean application accuracy in the first 5 cadavers was 4.3 mm (95% confidence interval [CI] 2.9–4.3 mm) and in the second 5 cadavers was 2.9 mm (95% CI 2–3.9 mm). The more superficial lesions were targeted significantly less accurately than the deeper lesions (P = 0.0183). Median machine accuracy was 0.1 mm and the range was 0.1–0.2 mm. Findings supported use of the new biopsy system for canine brain lesions >3.9 mm in diameter. 相似文献
66.
SR Sørensen V Gallego L Pérez IAE Butts J Tomkiewicz JF Asturiano 《Reproduction in domestic animals》2013,48(6):936-944
European eel, Anguilla anguilla, is a target species for future captive breeding, yet best methodology to estimate sperm density for application in in vitro fertilization is not established. Thus, our objectives were to evaluate methods to estimate European eel sperm density including spermatocrit, computer‐assisted sperm analysis (CASA) and flow cytometry (FCM), using Neubauer Improved haemocytometer as benchmark. Initially, relationships between spermatocrit, haemocytometer counts and sperm motility were analysed, as well as the effect of sperm dilution on haemocytometer counts. Furthermore, accuracy and precision of spermatocrit, applying a range of G‐forces, were tested and the best G‐force used in method comparisons. We found no effect of dilution on haemocytometer sperm density estimates, whereas motility associated positively with haemocytometer counts, but not with spermatocrit. Results from all techniques, spermatocrit, CASA and FCM, showed significant positive correlations with haemocytometer counts. The best correlation between spermatocrit and haemocytometer counts was obtained at 6000 × g (r = 0.68). Of two CASA variants, one or three photographic fields (CASA‐1 and CASA‐2), CASA‐2 showed a very high accuracy to haemocytometer counts (r = 0.93), but low precision (CV: CASA‐2 = 28.4%). FCM was tested with and without microfluorospheres (FCM‐1 and FCM‐2), and relationships to haemocytometer counts were highly accurate (FCM‐1: r = 0.94; FCM‐2: r = 0.88) and precise (CV: FCM‐1 = 2.5; FCM‐2 = 2.7%). Overall, CASA‐2 and FCM‐1 feature reliable methods for quantification of European eel sperm, but FCM‐1 has a clear advantage featuring highest precision and accuracy. Together, these results provide a useful basis for gamete management in fertilization protocols. 相似文献
67.
Glyphosate was recently evaluated for its potential to interact with the estrogen, androgen and thyroid (EAT) hormone pathways, including steroidogenesis, under the United States Environmental Protection Agency's (USEPA) Endocrine Disruptor Screening Program (EDSP), then by Germany, the rapporteur Member State who led the European Annex 1 renewal for glyphosate, and then by the European Food Protection Agency (EFSA) also as part of the Annex 1 renewal for glyphosate. Under the EDSP, 11 Tier 1 assays were run following the USEPA's validated 890‐series test guidelines and included five in vitro and six in vivo assays to evaluate the EAT pathways. Steroidogenesis was evaluated as part of the estrogen and androgen pathways. An up‐to‐date critical review has been conducted that considered results from the EDSP Tier 1 battery, guideline regulatory studies and an in‐depth analysis of the literature studies that informed an endocrine assessment. A strength of this evaluation was that it included data across multiple levels of biological organization, and mammalian and nonmammalian test systems. There was strong agreement across the in vitro and in vivo Tier 1 battery, guideline studies and relevant literature studies, demonstrating that glyphosate does not interact with EAT pathways including steroidogenesis. Based on an analysis of the comprehensive toxicology database for glyphosate and the literature, this review has concluded that glyphosate does not have endocrine‐disrupting properties through estrogen, androgen, thyroid and steroidogenic modes of action. © 2020 Society of Chemical Industry 相似文献
68.
Levine JM Fosgate GT Porter B Schatzberg SJ Greer K 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2008,22(4):961-968
BACKGROUND: Although the histopathologic features of necrotizing meningoencephalitis (NME) have been described previously, little information is available concerning the signalment, geographic distribution, seasonal onset, treatment, and survival of affected dogs. ANIMALS: Sixty Pugs with NME and 14 contemporaneous control Pugs with other intracranial diseases (non-NME group). METHODS: Pugs that were euthanized or died because of intracranial disease were prospectively obtained. All dogs had necropsy, histopathology, and testing for various infectious diseases and were subsequently divided into NME and non-NME groups. Signalment, geographic distribution, seasonal onset, treatment, and survival were compared between groups. RESULTS: In Pugs with NME, median age at onset of clinical signs was 18 months (range, 4-113 months). A greater proportion of female dogs were present in the NME group (40/60) compared with the control group (6/14). Pugs with NME had a significantly lower mean weight (7.81 kg) than control Pugs (9.79 kg) (P= .012). Mean survival in Pugs with NME was 93 days (range, 1-680 days), with dogs receiving any form of treatment living significantly longer than those that were not treated (P= .003). Anticonvulsive drugs were the only treatment significantly associated with longer survival (P= .003). CONCLUSIONS AND CLINICAL IMPORTANCE: NME appears to be a common cause of intracranial signs in Pugs, based on the high proportion of NME dogs reported in this population. Pugs with NME are most commonly young adult female dogs. Although further investigation is needed to determine the optimal treatment of NME, anticonvulsive drugs appear to beneficially affect duration of survival. 相似文献
69.
Levine JM Levine GJ Boozer L Schatzberg SJ Platt SR Kent M Kerwin SC Fosgate GT 《Journal of the American Veterinary Medical Association》2008,232(3):411-417
OBJECTIVE: To determine complications and neurologic outcomes associated with dexamethasone administration to dogs with surgically treated thoracolumbar intervertebral disk herniation, compared with dogs not receiving dexamethasone. DESIGN: Retrospective case series. ANIMALS: 161 dogs with surgically confirmed thoracolumbar disk herniation. PROCEDURES: Medical records from 2 hospitals were used to identify dogs that had received dexamethasone < 48 hours prior to admission (dexamethasone group dogs), dogs that received glucocorticoids other than dexamethasone < 48 hours prior to admission (other-glucocorticoid group dogs), and dogs that received no glucocorticoids (nontreatment group dogs). Signalment, neurologic injury grade, laboratory data, and complications were extracted from medical records. RESULTS: Dexamethasone group dogs were 3.4 times as likely to have a complication, compared with other-glucocorticoid or nontreatment group dogs. Dexamethasone group dogs were 11.4 times as likely to have a urinary tract infection and 3.5 times as likely to have diarrhea, compared with other-glucocorticoid or nontreatment group dogs. No differences in neurologic function at discharge or recheck evaluation were detected among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that treatment with dexamethasone before surgery is associated with more adverse effects, compared with treatment with glucocorticoids other than dexamethasone or no treatment with glucocorticoids, in dogs with thoracolumbar intervertebral disk herniation. In this study population, no difference in outcome was found among groups. These findings suggest that the value of dexamethasone administration before surgery in dogs with thoracolumbar disk herniation should be reconsidered. 相似文献
70.
Budke CM Levine JM Kerwin SC Levine GJ Hettlich BF Slater MR 《Journal of the American Veterinary Medical Association》2008,233(6):925-930
OBJECTIVE: To evaluate a questionnaire for obtaining owner-perceived, weighted quality-oflife assessments for dogs with spinal cord injuries. DESIGN: Evaluation study. Animals-100 dogs with spinal cord injuries and 48 healthy control dogs. PROCEDURES: The questionnaire was adapted from a questionnaire (the schedule for the evaluation of individual quality of life-direct weighting) used for human patients. Specifically, owners were asked to identify 5 areas or activities they believed had the most influence on their dogs' quality of life, assess their dogs' current status in each of those areas, and provide a weighting for the importance of each area. Results were used to construct a weighted quality-of-life score ranging from 0 to 100 for each dog. Owners were also asked to provide a quality-of-life score with a visual analog scale (VAS). RESULTS: A good correlation was found between weighted and VAS quality-of-life scores. Dogs with spinal cord injuries had weighted quality-of-life scores that were significantly lower than scores for control dogs. Quality-of-life areas and activities provided by owners of dogs with spinal cord injuries were similar to areas and activities provided by owners of healthy control dogs and could mostly be encompassed by 5 broader domains: mobility, play or mental stimulation, health, companionship, and other. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that the questionnaire could be used to obtain owner-perceived, weighted quality-of-life assessments for dogs with spinal cord injuries. Obtaining owner-perceived quality-of-life assessments for individual dogs should allow veterinarians to better address quality-of-life concerns and expectations of owners. 相似文献