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71.
Engelman JA Zejnullahu K Mitsudomi T Song Y Hyland C Park JO Lindeman N Gale CM Zhao X Christensen J Kosaka T Holmes AJ Rogers AM Cappuzzo F Mok T Lee C Johnson BE Cantley LC Jänne PA 《Science (New York, N.Y.)》2007,316(5827):1039-1043
The epidermal growth factor receptor (EGFR) kinase inhibitors gefitinib and erlotinib are effective treatments for lung cancers with EGFR activating mutations, but these tumors invariably develop drug resistance. Here, we describe a gefitinib-sensitive lung cancer cell line that developed resistance to gefitinib as a result of focal amplification of the MET proto-oncogene. inhibition of MET signaling in these cells restored their sensitivity to gefitinib. MET amplification was detected in 4 of 18 (22%) lung cancer specimens that had developed resistance to gefitinib or erlotinib. We find that amplification of MET causes gefitinib resistance by driving ERBB3 (HER3)-dependent activation of PI3K, a pathway thought to be specific to EGFR/ERBB family receptors. Thus, we propose that MET amplification may promote drug resistance in other ERBB-driven cancers as well. 相似文献
72.
Rogers CL 《Zoonoses and public health》2011,58(4):229-233
In 2003 the Texas Board of Health approved a modification to the Texas Administrative Code that permitted pet owners to have their dogs (Canis familiaris) and cats (Felis catus) vaccinated against rabies every 3 years, provided a triennial vaccine was used. The change had been opposed by hundreds in the veterinary community, some concerned that its implementation would be followed by a decrease in rabies vaccination rates. To determine if this decrease had occurred, rabies vaccination rates for 4 years before and after migration to the 3-year vaccination interval were examined. Data for dogs and cats, ≥ 4 months of age, were collected from the Texas Department of Health Rabies Incident Report database. Each animal's record included its current rabies vaccination status. The number of animals that were currently vaccinated against rabies was tallied and the percent vaccinated was calculated. From 1999 through 2002, 46% of dogs were vaccinated against rabies. From 2004 through 2007, 56% of dogs were vaccinated against rabies. From 1999 to 2002, 18% of cats were vaccinated against rabies. From 2004 to 2007, 30% of cats were vaccinated against rabies. There has been a significant increase in the numbers of dogs (P < 0.001), and cats (P < 0.001), vaccinated against rabies since the introduction of the triennial vaccination interval. This observational study documents the positive changes in rabies vaccination rates following migration from a 1-year to 3-year vaccination interval. 相似文献
73.
Naturally derived micelles for rapid in vitro screening of potential cholesterol-lowering bioactives
Kirana C Rogers PF Bennett LE Abeywardena MY Patten GS 《Journal of agricultural and food chemistry》2005,53(11):4623-4627
A high plasma cholesterol level, especially low-density lipoprotein cholesterol, indicates increased risk of cardiovascular diseases. Plasma cholesterol levels are influenced by diet and cholesterol biosynthesis, uptake, and secretion. Cholesterol uptake involves solubilization into complex phospholipid spherical bodies termed micelles that facilitate the transport of lipids through the gut brush border membrane into enterocytes. In vitro assays reported to date to determine potential cholesterol-lowering effects of various compounds require artificial micelle preparations that are elaborate and time-consuming to prepare. The aims of this study were to compare the efficacy of artificially prepared micelles with naturally derived micelles from pig's bile and to test their ability to assess potential inhibitors of cholesterol uptake. The suitability of pig's bile-derived micelles was tested both at the level of the micelle and at cellular uptake using cultured Caco-2 cells. Known cholesterol uptake inhibitors at the micelle (green tea catechins) and at the Caco-2 cell (beta-lactoglobulin-derived peptide, IIAEK) were used as reference inhibitory compounds. It was concluded that pig's bile was a rapid, reproducible, convenient, and cost-effective source of micelles for cholesterol micelle solubility and cellular uptake assay systems and is suitable for screening purposes focused on identifying potential cholesterol-lowering agents. 相似文献
74.
Thibodeau MS Poore MH Hagler WM Rogers GM 《Journal of agricultural and food chemistry》2004,52(2):380-384
Unfortunate bovine fatalities occurring after ingestion of mold-damaged sweetpotatoes preclude the use of the culled tubers in livestock feed. In cattle, mold-damaged sweetpotatoes induce an acute respiratory distress syndrome resulting in asphyxiation. Because of this potential toxicity and the general abundance of culled sweetpotatoes, the detoxification efficacy of ensiling was explored since it is an easy and economically viable technique often applied to preserve livestock feed. Sweetpotato slices with or without mold damage were stored either frozen (to represent unfermented samples) or fermented for 6 weeks at room temperature. Following fermentation, organic extracts were generated for administration to mice. Thirty hours following administration of the extracts, mice were evaluated for gross and microscopic lesions affecting the lungs, liver, and kidneys. Fermentation of 6 weeks duration was observed to inadequately eliminate the lung, liver, and kidney toxicity caused by mold-damaged sweetpotatoes. In fact, fermentation exacerbated the hepatotoxicity of mold-damaged sweetpotatoes. This is also the first demonstration that sweetpotato regions lacking visible mold damage can induce lung and kidney injury, which, however, is preventable by fermentation. 相似文献
75.
76.
The purpose of this study was to find out if an LMA (#1 LMA‐Classic) would provide a better airway than a face mask in spontaneously breathing anesthetized rabbits, and to test if it could be used for mechanically controlled ventilation. Sixteen rabbits (4.1 ± 0.8 kg, mean ± SD) were assigned randomly to three treatment groups; face mask with spontaneous ventilation (FM‐SV; n = 5), LMA with spontaneous ventilation (LMA‐SV; n = 5), and LMA with controlled ventilation (LMA‐CV; n = 6). Rabbits were anesthetized in dorsal recumbency using a circle circuit at constant ET isoflurane (2.3%, Datex airway gas monitor) and constant rectal temperature (38.85 °C) for 2 hours. PaCO2, PaO2, minute volume, tidal volume (Wright's respirometer), and Pe CO2 were measured at 15 minute intervals. Two individuals in the FM‐SV group had PaCO2 >100 mm Hg (>13.3 kPa). One rabbit in the FM‐SV had PaO2 <80 mm Hg (<10.7 kPa). All FM‐SV rabbits showed signs of airway obstruction and two were withdrawn from the study at 45 and 90 minutes, respectively, because of cyanosis. Tidal volume could not be measured in the FM‐SV group. No signs of airway obstructions were observed in either of the LMA groups. Four rabbits in the LMA‐CV group developed gastric tympany, and one of these refluxed after 110 minutes. The significance of differences between the two spontaneously breathing groups and between the two LMA groups were measured using Wilcoxon's rank sum test (with significance assumed at p < 0.05). There were no statistical differences between FM‐SV and LMA‐SV in any variable tested. PaCO2 and Pe ′CO2 were less in the LMA‐CV group than in the LMA‐SV group, while PaO2, tidal volume, and minute volume were all more. We conclude that biologically, the LMA provides a better airway than the face mask during spontaneous breathing and that it can be used for IPPV, but that gastric tympany is likely to occur during IPPV. 相似文献
77.
Monica Rogers DVM Robert E. Cartee DVM MS William Miller DVM Ahmed K. Ibrahim MVSc PhD 《Veterinary radiology & ultrasound》1986,27(1):24-29
B-mode ultrasonography using a 7.5 megahertz (MHz ) transducer was performed on 95 equine cadaver eyes submerged in a water bath. Identification and measurement of the anterior to posterior diameters of the intraocular structures and of the axis bulbi was done. The dorsal ventral axis of the eye was also measured. The eyes were then frozen, sectioned in a saggital plane and the same measurements were made using calipers. Two sets of measurements were then compared statistically.
With the exception of the cornea and the dorsal ventral axis measurements of male horses there was no statistically significant difference in the measurements obtained by the two methods.
The use of B-mode ultrasonography at a frequency of 7.5 MHz to examine the architecture of the equine eye is suggested as a valuable clinical tool. Biometry of the intraocular structures at this frequency may be reasonably accurate. 相似文献
With the exception of the cornea and the dorsal ventral axis measurements of male horses there was no statistically significant difference in the measurements obtained by the two methods.
The use of B-mode ultrasonography at a frequency of 7.5 MH
78.
S C Zicker M S Spensley Q R Rogers N H Willits 《American journal of veterinary research》1991,52(7):1014-1018
The concentrations of 23 amino acids in the plasma of 13 healthy foals were determined before suckling, when foals were 1 to 2 days old, 5 to 7 days old, 12 to 14 days old, and 26 to 28 days old. The ratio of the branched chain amino acids to the aromatic amino acids was also calculated at the 5 time points. Analysis of the concentrations at the 5 ages revealed a significant temporal relationship for each amino acid ranging from a polynomial order of 1 to 4 inclusively. There were significant differences between several concentrations of amino acids in plasma at specific sample times; however, no consistent patterns were revealed. The concentrations of amino acids in healthy foals were markedly different from previously determined values in adult horses. The significant differences in the concentrations of amino acids in plasma of healthy foals at the 5 ages may represent developmental aspects of amino acid metabolism or nutrition. 相似文献
79.
80.
Plasma amino acid concentrations were determined weekly for 4 weeks in 6 sham-operated control dogs, in 6 sham-operated dogs after induction of liver disease with dimethylnitrosamine (DMNA), and in 6 dogs after surgical ligation of the common bile duct. Results were compared with standard biochemical indices of liver function and with histologic changes in serial liver biopsy specimens. Concentrations of most amino acids increased after 2 weeks in DMNA-treated dogs, whereas they were normal or decreased in bile duct-ligated dogs. With increasing severity of the liver disease, the molar ratio (normal mean +/- SEM = 3.48 +/- 0.14) in DMNA-treated dogs decreased to 2.42 +/- 0.19 by 2 weeks and to 1.17 +/- 0.09 by 4 weeks. The ratio remained normal in bile duct-ligated dogs. Molar ratio and aromatic amino acid concentrations correlated better with hepatic necrosis and inflammation than did standard biochemical indices (eg, bilirubin, liver enzymes). Therefore, plasma amino acid analysis and determination of the molar ratio may be useful in the differential diagnosis of hepatocellular and obstructive jaundice in dogs. A decrease in the molar ratio may reflect portal hypertension and hepatocellular disease. 相似文献