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31.
32.
The mTOR-regulated phosphoproteome reveals a mechanism of mTORC1-mediated inhibition of growth factor signaling 总被引:1,自引:0,他引:1
Hsu PP Kang SA Rameseder J Zhang Y Ottina KA Lim D Peterson TR Choi Y Gray NS Yaffe MB Marto JA Sabatini DM 《Science (New York, N.Y.)》2011,332(6035):1317-1322
The mammalian target of rapamycin (mTOR) protein kinase is a master growth promoter that nucleates two complexes, mTORC1 and mTORC2. Despite the diverse processes controlled by mTOR, few substrates are known. We defined the mTOR-regulated phosphoproteome by quantitative mass spectrometry and characterized the primary sequence motif specificity of mTOR using positional scanning peptide libraries. We found that the phosphorylation response to insulin is largely mTOR dependent and that mTOR exhibits a unique preference for proline, hydrophobic, and aromatic residues at the +1 position. The adaptor protein Grb10 was identified as an mTORC1 substrate that mediates the inhibition of phosphoinositide 3-kinase typical of cells lacking tuberous sclerosis complex 2 (TSC2), a tumor suppressor and negative regulator of mTORC1. Our work clarifies how mTORC1 inhibits growth factor signaling and opens new areas of investigation in mTOR biology. 相似文献
33.
Cassandra Mellish tienne Ct Enrique Aburto Jonathan Lichtenberger 《The Canadian veterinary journal. La revue veterinaire canadienne》2022,63(4):411
A 12-year-old castrated male cocker spaniel dog was referred for evaluation of signs consistent with right-sided heart failure. Thoracic radiography revealed mineralization in the region of the right atrium. Echocardiography identified a mass partially filling the right atrium and right ventricle and obstructing flow through the right heart. These findings were confirmed at necropsy and histopathologic features were consistent with myxoma with chondroid differentiation. 相似文献
34.
Gawain J. C. Hammond Martin Sullivan Steven Weinrauch Alison M. King 《Veterinary radiology & ultrasound》2005,46(3):205-209
Fluid within the tympanic bulla is an indication of middle ear disease. Radiography has a relatively low accuracy for the detection of soft tissue opacification in the tympanic bulla, and the most useful radiographic projection, the rostrocaudal open mouth (RCd (open mouth)), is technically difficult to perform in dogs and cats. An alternative projection for the feline tympanic bulla, the rostro 10 degrees ventro-caudodorsal oblique (R10 degrees V-CdDO), was compared to the RCd (open mouth) in 41 feline cadaver heads with the tympanic bullae randomly filled with KY jelly. Computed tomography was used as the gold standard. Each tympanic bulla was recorded as being positive or negative for soft tissue opacification. Although there was no significant difference between the accuracy of the two views, the R10 degrees V-CdDO was subjectively more accurate and easier to perform, and in a live patient may be performed without the need for general anesthesia. The R10 degrees V-CdDO projection is a good alternative to the RCd (open mouth) projection for detecting otitis media in the cat. 相似文献
35.
Alan R. McCaffery Jonathan W. Holloway Richard T. Gladwell 《Pest management science》1995,44(3):237-247
Spontaneous neuronal activity was recorded from the peripheral nerves of third-instar larvae of strains of Heliothis virescens (F.) obtained directly from cotton fields in the USA. Following a control period the preparations were exposed to increasing concentrations of cis-cypermethrin in a cumulative dose-response assay. A positive response was defined as an increase of at least five-fold in the rate of neuronal activity over that seen during the control period. Up to 35 individuals of each strain were assayed and the responses used to construct a phenotypic profile categorising the individuals from nerve-susceptible to highly nerve-insensitive. An EC50 for the action of cis-cypermethrin was also obtained. There was a positive, significant correlation between non-synergisable resistance to cypermethrin and nerve insensitivity as defined in the neurophysiological assay. It was shown that nerve insensitivity to cypermethrin increased throughout the cotton-growing season. 相似文献
36.
Jonathan H. Foreman D.V.M. Stephen M. Reed D.V.M. Norman W. Rantanen D.V.M. M.S. Richard M. DeBowes D.V.M. M.S. Pamela C. Wagner D.V.M. M.S. 《Journal of Equine Veterinary Science》1983,3(5):154-164
Since the normal absorption of CSF occurs in the cerebral veins and venous sinuses, any obstruction to the normal flow and absorption of CSF will result in accumulation of CSF central to the site of obstruction. Such accumulation within the cranium is defined as hydrocephalus.A foal was presented with an enlarged and an abnormally-shaped skull, but with normal behavior. The filly's condition deteriorated. Radiographs showed a domeshaped cranial vault with compression of the frontal sinus region. Massive hydrocephalus with little normal cerebral tissue left was diagnosed with ultrasound.Surgery was attempted to relieve the pressure. Eventually the foal was euthanized. Post-mortem confirmed the radiographic and ultrasound diagnosis. Since there was a lack of demonstrable obstruction, the authors suspected the foal had suffered from the Arnold-Chiari syndrome. 相似文献
37.
LEPTOSPIROSIS IN ANIMALS AND MAN 总被引:3,自引:0,他引:3
38.
39.
Doust R Sullivan M 《Journal of the American Veterinary Medical Association》2003,222(10):1385-7, 1365-6
A 5-year-old sexually intact female Yorkshire Terrier was referred with a history of fecal incontinence of at least 2 years and chronic intermittent colitis. The external anal sphincter to the left of the anus was intact; the external anal sphincter was not detectable to the right of the anus. To repair the defect, the semitendinosus muscle was isolated and severed 2 cm proximal to its insertion on the tibia. Care was taken to preserve the integrity of the vasculature and nerve supply in the proximal third of the muscle body. The body of the muscle was passed around the ventral and right aspects of the rectum; the cut end was secured with simple interrupted sutures dorsal to the levator ani and coccygeus muscles to simulate the external anal sphincter. After surgery, the dog could defecate normally. Absence of a portion of the external anal sphincter may be congenital or the result of anorectal trauma, rectal prolapse, severe perineal disease, or surgical resection. The use of a semitendinosus muscle flap for treatment of fecal incontinence secondary to sphincter incompetence in dogs may be a viable alternative to euthanasia. 相似文献
40.
OBJECTIVE: To determine in vitro vasoactive potency of monoamines formed in the cecum and found in the systemic circulation of horses. SAMPLE POPULATION: Segments of digital blood vessels obtained from 6 healthy mixed-breed horses and ponies euthanatized at an abattoir and platelets isolated from 4 healthy ponies. PROCEDURE: Paired rings of digital artery and vein from the same horse were examined, and isometric tension was recorded. Concentration-response curves for tryptamine (TRP), tyramine (TYR), phenylethylamine (PEA), isoamylamine (IAA), and isobutylamine (IBA) were obtained. Vasoconstrictor mechanisms were investigated for TRP and TYR by the use of antagonists. Washed platelets loaded with [3H]-5-hydroxytryptamine (5-HT) were incubated with monoamines; the amount of radioactivity displaced after 30 minutes was estimated. RESULTS: TRP, TYR, and PEA were potent constrictors of arteries and veins, with TRP and TYR being more potent in veins than arteries. Constrictions induced by TYR were inhibited by benextramine (alpha-antagonist) and nisoxetine (neuronal-uptake blocker), whereas TRP responses were inhibited by ketanserin (5-HT receptor antagonist). All 5 amines displaced 5-HT from platelets with the order of potency being TYR > TRP > PEA > IAA > IBA. CONCLUSIONS AND CLINICAL RELEVANCE: Amines from the equine cecum cause digital vasoconstriction. The most potent (TRP and TYR) cause selective venoconstriction. Tyrosine activates predominantly alpha-adrenoceptors through the release of neuronal norepinephrine, whereas TRP activates 5-HT receptors. All amines tested released 5-HT from platelets. Amines formed in the cecum and released into the systemic circulation warrant additional investigation as trigger factors for digital ischemia and subsequent laminitis. 相似文献