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1.
Eric S. Goetzman John F. Alcorn Sivakama S. Bharathi Radha Uppala Kevin J. McHugh Beata Kosmider Rimei Chen Yi Y. Zuo Megan E. Beck Richard W. McKinney Helen Skilling Kristen R. Suhrie Anuradha Karunanidhi Renita Yeasted Chikara Otsubo Bryon Ellis Yulia Y. Tyurina Valerian E. Kagan Rama K. Mallampalli Jerry Vockley 《The Journal of biological chemistry》2014,289(15):10668-10679
Long-chain acyl-CoA dehydrogenase (LCAD) is a mitochondrial fatty acid oxidation enzyme whose expression in humans is low or absent in organs known to utilize fatty acids for energy such as heart, muscle, and liver. This study demonstrates localization of LCAD to human alveolar type II pneumocytes, which synthesize and secrete pulmonary surfactant. The physiological role of LCAD and the fatty acid oxidation pathway in lung was subsequently studied using LCAD knock-out mice. Lung fatty acid oxidation was reduced in LCAD−/− mice. LCAD−/− mice demonstrated reduced pulmonary compliance, but histological examination of lung tissue revealed no obvious signs of inflammation or pathology. The changes in lung mechanics were found to be due to pulmonary surfactant dysfunction. Large aggregate surfactant isolated from LCAD−/− mouse lavage fluid had significantly reduced phospholipid content as well as alterations in the acyl chain composition of phosphatidylcholine and phosphatidylglycerol. LCAD−/− surfactant demonstrated functional abnormalities when subjected to dynamic compression-expansion cycling on a constrained drop surfactometer. Serum albumin, which has been shown to degrade and inactivate pulmonary surfactant, was significantly increased in LCAD−/− lavage fluid, suggesting increased epithelial permeability. Finally, we identified two cases of sudden unexplained infant death where no lung LCAD antigen was detectable. Both infants were homozygous for an amino acid changing polymorphism (K333Q). These findings for the first time identify the fatty acid oxidation pathway and LCAD in particular as factors contributing to the pathophysiology of pulmonary disease. 相似文献
2.
Yogeeta O. Agrawal Pankaj Kumar Sharma Birendra Shrivastava Shreesh Ojha Harshita M. Upadhya Dharamvir Singh Arya Sameer N. Goyal 《PloS one》2014,9(11)
The present study investigated the effect of hesperidin, a natural flavonoid, in cardiac ischemia and reperfusion (I/R) injury in diabetic rats. Male Wistar rats with diabetes were divided into five groups and were orally administered saline once daily (IR-sham and IR-control), Hesperidin (100 mg/kg/day; IR-Hesperidin), GW9962 (PPAR-γ receptor antagonist), or combination of both for 14 days. On the 15th day, in the IR-control and IR-treatment groups, rats were subjected to left anterior descending (LAD) coronary artery occlusion for 45 minutes followed by a one-hour reperfusion. Haemodynamic parameters were recorded and rats were sacrificed; hearts were isolated for biochemical, histopathological, ultrastructural and immunohistochemistry. In the IR-control group, significant ventricular dysfunctions were observed along with enhanced expression of pro-apoptotic protein Bax. A decline in cardiac injury markers lactate dehydrogenase activity, CK-MB and increased content of thiobarbituric acid reactive substances, a marker of lipid peroxidation, and TNF-α were observed. Hesperidin pretreatment significantly improved mean arterial pressure, reduced left ventricular end-diastolic pressure, and improved both inotropic and lusitropic function of the heart (+LVdP/dt and –LVdP/dt) as compared to IR-control. Furthermore, hesperidin treatment significantly decreased the level of thiobarbituric acid reactive substances and reversed the activity of lactate dehydrogenase towards normal value. Hesperidin showed anti-apoptotic effects by upregulating Bcl-2 protein and decreasing Bax protein expression. Additionally, histopathological and ultrastructural studies reconfirmed the protective action of hesperidin. On the other hand, GW9662, selective PPAR-γ receptor antagonist, produced opposite effects and attenuated the hesperidin induced improvements. The study for the first time evidence the involvement of PPAR-γ pathway in the cardioprotective activity of hesperidin in I/R model in rats. 相似文献
3.
A number of methods of construction of partially balanced incomplete block designs with nested rows and columns are developed and new balanced incomplete block designs with nested rows and columns are obtained as a by-product. 相似文献
4.
Heteromazocraes mamaevi n. sp. is described from a cyprinid, Securicula gora (Ham.) from the Lucknow district, India. It is characterised by well-developed cephalic glands, the shape of the genital spines, the structure of the egg and the shape of the clamp sclerites. This is the first record of the genus Heteromazocraes Mamaev, 1981 from a cyprinid fish. 相似文献
5.
Oligodeoxynucleotide-containing phosphorothioate backbones have been used to regulate viral as well as cellular gene expression. The studies carried out in tissue culture have shown promising results on the use of oligonucleotide phosphorothioates as antiviral agents and, at present, study is underway to develop these oligonucleotide analogues as chemotherapeutic agents. To analyze and purify oligonucleotide analogues, high-performance liquid chromatography using weak anion exchange column has been described. The separation of oligonucleotide phosphorothioate is found to be length dependent. 相似文献
6.
Tracheal Na+-K+-ATPase activity is positively correlated with in vivo airway responsiveness to histamine. We wondered whether this were a chance association or whether it was directly related to the mechanism of hyperreactivity. Therefore, we obtained dose-response curves to aerosols of histamine and ouabain in guinea pigs to determine whether an in vivo relationship existed between the excitatory effects of histamine and the enzyme-inhibiting effect of ouabain. Airway responsiveness to ouabain was measured as the ouabain concentration producing a 30% decrease in specific airway conductance (ED30) or that producing a half-maximal response (ED50). Responsiveness to histamine was measured either as ED30 or as ED50. Significant positive correlations were noted between the log ED50 of ouabain and log histamine ED30 or ED50 (r = 0.81 and 0.83, respectively; P less than 0.001), and between log ouabain ED30 and log histamine ED30 and ED50 (r = 0.76 and 0.77, respectively; P less than 0.002). Pretreatment with ouabain increased airway responsiveness to histamine (P less than 0.05). We suggest that in hyperreactive airways Na+-K+-ATPase serves a homeostatic function of preventing Na+ and Ca2+ loading of the cell and that it is not directly responsible for the hyperreactivity. 相似文献
7.
Comparative tissue ascorbic acid studies in fishes 总被引:1,自引:0,他引:1
Comparative tissue ascorbic acid levels in four species of major carp viz., Labeo rohila, L. calbasu, Cirrhina tnrigala and Catla catla , were investigated. The ascorbic acid level was found to be the highest in the spleen in the four species studied (range 430–380 μg/g) followed by the anterior (adrenal) kidney, gonads, liver, renal kidney, brain and/or eye. Heart and blood had the lowest levels (range 26–18 μg/ml) amongst the tissues studied. Overall tissue ascorbic acid levels were the highest in L. rohita and the lowest in C. mrigala . Investigation on seasonal variations in blood and kidney ascorbic acid levels of Notopterus notopterus revealed peak levels in spring (February-April) and the lowest levels in the postspawning period (August-September). 相似文献
8.
The present study focusses on the effects of pH, temperature, intensity of white, red far-red light on zygospore germination
in the filamentous green algaSpirogyra hyalina. Maximum germination of zygospores occurred at pH 8.0 and 25°C. Germination of zygospores was favored by white light at an
intensity of 3–4 klx. Red light resulted in higher germination when applied at the beginning or in the middle of the dark
period, while far-red light decreased zygospore germination. Red light in the middle of the dark period was found to be most
effective for germination. These observations suggest a possible presence of the phytochrome system in the test alga contributing
to its morphogenetic response. 相似文献
9.
We studied case construction behavior of bagworm moth, Eumeta crameri (Lepidoptera: Psychidac) in the host plant, Acacia nilotica, at two sites. At the time of the study, Site A had 1-year-old A. nilotica saplings only, whereas Site B had full grown trees. The larva of bagworm moth used either thorns or cut-twigs or both as the materials for building its case. It renovated its case three times, and during each instance it increased the volume of its case by replacing older thorns or cut-twigs by newer and longer ones. However, it exhibited a spectacular predilection for thorns, irrespective of the sites, during the first-instar stage of its development. Thereafter, at Site A it used exclusively cut-twigs, whereas at Site B it preferably used thorns provided they were available in the range of the required length and within the threshold distance. It appears that the bagworm has an ability to process thorn length and distance signals hierarchically to fulfill its priority, that is, case building. Thus it optimizes time and energy expenditures during the period of its larval growth leading to pupation by toggling its preference between thorns and cut-twigs. 相似文献
10.