A phylogenomic study of birds reveals their evolutionary history     

Hackett SJ  Kimball RT  Reddy S  Bowie RC  Braun EL  Braun MJ  Chojnowski JL  Cox WA  Han KL  Harshman J  Huddleston CJ  Marks BD  Miglia KJ  Moore WS  Sheldon FH  Steadman DW  Witt CC  Yuri T 《Science (New York, N.Y.)》2008,320(5884):1763-1768

Deep avian evolutionary relationships have been difficult to resolve as a result of a putative explosive radiation. Our study examined approximately 32 kilobases of aligned nuclear DNA sequences from 19 independent loci for 169 species, representing all major extant groups, and recovered a robust phylogeny from a genome-wide signal supported by multiple analytical methods. We documented well-supported, previously unrecognized interordinal relationships (such as a sister relationship between passerines and parrots) and corroborated previously contentious groupings (such as flamingos and grebes). Our conclusions challenge current classifications and alter our understanding of trait evolution; for example, some diurnal birds evolved from nocturnal ancestors. Our results provide a valuable resource for phylogenetic and comparative studies in birds.  相似文献   

Protection from cardiac arrhythmia through ryanodine receptor-stabilizing protein calstabin2     

Wehrens XH  Lehnart SE  Reiken SR  Deng SX  Vest JA  Cervantes D  Coromilas J  Landry DW  Marks AR 《Science (New York, N.Y.)》2004,304(5668):292-296

Ventricular arrhythmias can cause sudden cardiac death (SCD) in patients with normal hearts and in those with underlying disease such as heart failure. In animals with heart failure and in patients with inherited forms of exercise-induced SCD, depletion of the channel-stabilizing protein calstabin2 (FKBP12.6) from the ryanodine receptor-calcium release channel (RyR2) complex causes an intracellular Ca2+ leak that can trigger fatal cardiac arrhythmias. A derivative of 1,4-benzothiazepine (JTV519) increased the affinity of calstabin2 for RyR2, which stabilized the closed state of RyR2 and prevented the Ca2+ leak that triggers arrhythmias. Thus, enhancing the binding of calstabin2 to RyR2 may be a therapeutic strategy for common ventricular arrhythmias.  相似文献   

Influence of Fluid Delivery Schedule and Composition on Fluid Balance,Physiologic Strain,and Substrate Use in the Heat     

Alejandro M. Rosales  Walter S. Hailes  Patrick S. Dodds  Alexander N. Marks  Brent C. Ruby 《The Forestry Chronicle》2021,32(1):27-35

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Coupling stable isotope studies with food web manipulations to predict the effects of exotic fish: lessons from Cuatro Ciénegas,Mexico     

Jane C. Marks  Christopher Williamson  Dean A. Hendrickson 《水产资源保护:海洋与淡水生态系统》2011,21(4):317-323

• 1. Exotic species threaten native species worldwide, but their impacts are difficult to predict.
• 2. Stable isotope analysis was combined with field competition experiments to predict how an invasive African cichlid fish, Hemichromis guttatus, might affect native fish in the desert springs of Cuatro Ciénegas, Mexico.
• 3. Stable isotope analysis suggested diet overlap between the invader and juvenile endemic cichlids, and field experiments verified that the invader reduces growth rates of the juvenile endemics through competition, but has smaller effects on adults.
• 4. Competition between juvenile endemic cichlids and the invader was asymmetric, with the exotic out‐competing the native, suggesting the potential for competitive exclusion if the invasion is not stopped.
• 5. These results suggest that exotic removal programmes in Cuatro Ciénegas should focus on removing/reducing populations of the exotic cichlid in habitats where juvenile native cichlids are concentrated.
• 6. This approach could help focus efforts to manage exotic species before populations of native species have crashed, when it is too late to intervene.

Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

Effect of intravenous administration of dextrose on coagulation in healthy dogs     

Gonzales JL  Hanel RM  Hansen BD  Marks SL 《American journal of veterinary research》2011,72(4):562-569

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Simultaneous quantification of eight biogenic amine compounds in tuna by matrix solid-phase dispersion followed by HPLC-orbitrap mass spectrometry     

Self RL  Wu WH  Marks HS 《Journal of agricultural and food chemistry》2011,59(11):5906-5913

A method for the extraction of agmatine, cadaverine, histamine, phenyethylamine, putrescine, tryptamine, tyramine, and urocanic acid from canned tuna and frozen tuna loin matrices by matrix solid-phase dispersion, followed by separation and quantification of these compounds by ultrahigh-performance hydrophilic interaction chromatography (UHPLC-HILIC) with orbitrap mass spectrometric detection, is described. Tuna samples are dispersed in a CN-silica sorbent and eluted with a mixture of aqueous ammonium formate buffer and acetonitrile. Separation and detection are carried out on an Agilent 1200 high-performance liquid chromatograph coupled to a Thermo Exactive orbitrap mass spectrometer, and metformin is used as the internal standard. Spike recoveries are determined across a range of 20-100 ppm for each compound, and the method is validated with respect to linearity, reproducibility, accuracy, and limits of quantitation and detection. The method is demonstrated to be suitable for use in quantifying these target compounds in the studied matrices.  相似文献   

Reversible encephalopathy secondary to thiamine deficiency in 3 cats ingesting commercial diets     

Marks SL  Lipsitz D  Vernau KM  Dickinson PJ  Draper W  Larsen JA  Fascetti AJ 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2011,25(4):949-953

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Mortality associated with melarsomine dihydrochloride administration in two North American river otters (Lontra canadensis) and a red panda (Ailurus fulgens fulgens).   总被引：1，自引：0，他引：1  

Donald L Neiffer  Edwin C Klein  Paul P Calle  Michael Linn  Scott P Terrell  Rodney L Walker  Donna Todd  Carol C Vice  Steven K Marks 《Journal of zoo and wildlife medicine》2002,33(3):242-248

Two adult North American river otters (Lontra canadensis) and an adult red panda (Ailurus fulgens fulgens) at three separate institutions died within 22 hr after receiving single 2.5- to 2.7-mg/kg doses of melarsomine dihydrochloride administered in the epaxial musculature as a treatment for filarid nematodes. One otter had a suspected Dirofilaria immitis infection, the other had a confirmed D. lutrae infection, and the red panda had a confirmed Dirofilaria sp. infection, presumably with D. immitis. Postmortem examinations revealed similar gross lesions, although they were less severe in the red panda. The trachea and primary bronchi contained abundant foamy fluid, the lungs were mottled with areas of consolidation, and the pulmonary parenchyma exuded abundant fluid at the cut section. Histologic evaluation revealed acute pulmonary edema, which resulted in respiratory failure and death. There may have been direct pulmonary cellular toxicity of melarsomine dihydrochloride or a severe systemic anaphylactic reaction to antigens released after parasite death. An idiosyncratic drug reaction or a low therapeutic index of melarsomine probably caused the death of the three individuals. Melarsomine dihydrochloride use should be avoided in North American river otters and red pandas.  相似文献   

Presumptive Intramural Gastric Hemorrhage Secondary to Rodenticide Intoxication in a Dog     

Steven L. Marks BVSc  MS  MCVS  DACVIM  Tracy L. Gieger DVM  DACVIM  Jamie Williams MS  DVM  DACVR 《Journal of Veterinary Emergency and Critical Care》2001,11(1):27-31.

A dog being treated for demodicosis with ivermectin was presented for intermittent vomiting. The vomiting progressed to hematemesis and an underlying coagulopathy was diagnosed. The etiology of the coagulopathy was determined to be ingested brodifacoum. Ultrasound evaluation of the abdomen revealed thickened gastric wall that was suspected to be intramural hemorrhage. Most likely, the intramural hemorrhage and resulting thickening of the stomach wall led to the clinical signs and metabolic alkalosis. This case represents an typical presentation of hemorrhage secondary to rodenticide intoxication. (J Vet Emerg Crit Care 2001; 11(1):27–31, 2001).  相似文献   

Comparison of direct immunofluorescence, immunoassays, and fecal flotation for detection of Cryptosporidium spp. and Giardia spp. in naturally exposed cats in 4 Northern California animal shelters     

Mekaru SR  Marks SL  Felley AJ  Chouicha N  Kass PH 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(5):959-965

BACKGROUND: Giardia spp. and Cryptosporidium spp. are common intestinal protozoan parasites in domestic cats. Few studies have critically evaluated the performance characteristics of commercially available immunoassays for detection of these organisms in the cat. HYPOTHESIS: Human-based immunoassays are suboptimal for the detection of Giardia spp. and Cryptosporidium spp. in cats. ANIMALS: Three-hundred-and-forty-four cats with diarrheic and nondiarrheic fecal specimens at 4 northern California animal shelters. METHODS: A fecal specimen was collected from each cat in a case-controlled fashion. Fecal specimens were tested for Giardia spp. and Cryptosporidium spp. by using centrifugation flotation and 5 commercially available immunoassays (SNAP Giardia, ProSpecT Giardia Microplate Assay, ProSpecT Cryptosporidium Microplate Assay, ImmunoCard STAT! Cryptosporidium/ Giardia Rapid Assay, and Xpect Giardia/Cryptosporidium). Results were compared with a reference standard, the MeriFluor direct immunofluorescence assay. RESULTS: Overall prevalences of Giardia spp. and Cryptosporidium spp. were 9.8 and 4.7%, respectively. The ProSpecT Microplate Assay had the highest sensitivities and specificities for Giardia spp. (91.2 and 99.4%) and Cryptosporidum spp. (71.4 and 96.7%), respectively. The SNAP Giardia antigen assay was easier to use and equally sensitive (85.3%) and specific (100%) to fecal flotation. CONCLUSIONS AND CLINICAL IMPORTANCE: Caution should be exercised when using human-based immunoassays for the diagnosis of Giardia and Cryptosporidium spp. in cats. Fecal flotation remains a useful method for detection of Giardia spp., can be used to detect other parasites, and has a sensitivity of 97.8% for detection of Giardia spp. when combined with the SNAP Giardia immunoassay.  相似文献