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1.
Vijay Pal Singh Rangoli Aggarwal Suchita Singh Arpita Banik Tanveer Ahmad Bijay Ranjan Patnaik Giridharan Nappanveettil Kunal Pratap Singh Madan Lal Aggarwal Balaram Ghosh Anurag Agrawal 《PloS one》2015,10(6)
Epidemiological studies have shown an increased obesity-related risk of asthma. In support, obese mice develop airway hyperresponsiveness (AHR). However, it remains unclear whether the increased risk is a consequence of obesity, adipogenic diet, or the metabolic syndrome (MetS). Altered L-arginine and nitric oxide (NO) metabolism is a common feature between asthma and metabolic syndrome that appears independent of body mass. Increased asthma risk resulting from such metabolic changes would have important consequences in global health. Since high-sugar diets can induce MetS, without necessarily causing obesity, studies of their effect on arginine/NO metabolism and airway function could clarify this aspect. We investigated whether normal-weight mice with MetS, due to high-fructose diet, had dysfunctional arginine/NO metabolism and features of asthma. Mice were fed chow-diet, high-fat-diet, or high-fructose-diet for 18 weeks. Only the high-fat-diet group developed obesity or adiposity. Hyperinsulinemia, hyperglycaemia, and hyperlipidaemia were common to both high-fat-diet and high-fructose-diet groups and the high-fructose-diet group additionally developed hypertension. At 18 weeks, airway hyperresponsiveness (AHR) could be seen in obese high-fat-diet mice as well as non-obese high-fructose-diet mice, when compared to standard chow-diet mice. No inflammatory cell infiltrate or goblet cell metaplasia was seen in either high-fat-diet or high-fructose-diet mice. Exhaled NO was reduced in both these groups. This reduction in exhaled NO correlated with reduced arginine bioavailability in lungs. In summary, mice with normal weight but metabolic obesity show reduced arginine bioavailability, reduced NO production, and asthma-like features. Reduced NO related bronchodilation and increased oxo-nitrosative stress may contribute to the pathogenesis. 相似文献
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Two new compounds, isolated from the rhizomes of Cryptocoryne spiralis, have been characterized as ethyl 14-oxotetracosanoate and 15-oxoeicosanyl 14-oxoheptadecanoate by spectral data and chemical studies. Hentriacontane and sitosterol have also been isolated and identified. 相似文献
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Two thioredoxin cDNAs from soybean were isolated by screening an expression library using an anti-(plasma membrane) serum. The nucleotide sequences of the two cDNAs were found to be 89% identical. The polypeptides encoded by the two cDNAs, designated TRX1 and TRX2, contain a disulfide active site, as found in other thioredoxins. TRX1 was expressed as a fusion protein in Escherichia coli and shown to possess thiol-disufide interchange activity. Unlike other eukaryotic thioredoxins, these two soybean thioredoxins contain a putative transmembrane domain in their N-terminal regions. To determine subcellular location, the TRX1 was fused with a reporter epitope at its C-terminus and expressed in transgenic tobacco plants. The fusion protein was co-purified with plasma membrane markers 1,3-glucan synthase and vanadate-sensitive ATPase, indicating the plasma membrane location of TRX1. When the reporter epitope was inserted between the start codon and the transmembrane domain in the N-terminus, the fusion protein was found in the soluble fraction, possibly due to disruption of the transmembrane domain by the highly hydrophilic epitope sequence. Taken together, our results demonstrate that soybean TRX1 is a plasma membrane-bound thioredoxin, which is most likely anchored to the membrane through the N-terminal transmembrane domain. It is known that plant plasma membranes contain various proteins with thiol-disulfide interchange activity. The soybean thioredoxins reported here are the first group of such proteins to be characterized at the molecular level. However, the biological function of the plasma membrane-bound thioredoxin remains to be determined. 相似文献
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This study examined the effect of gestation on the hypophyseal responsiveness of buffalo to GnRH-induced LH and FSH release. Peripheral plasma LH and FSH concentrations were measured at 1 h before and upto 6 h after administration of GnRH (1 ug/kg body weight) or saline at Days 60, 150 and 240 of gestation in 2 groups of buffalo (n = 4 each). Basal LH concentrations did not vary at the 3 stages of gestation, while basal FSH concentrations exhibited a significant reduction (P < 0.05) from Day 60 to Day 150 of gestation. There was a significant reduction in the total LH (P < 0.05) and FSH (P < 0.01) released in response to GnRH from Day 60 to Day 240 of gestation. The duration of LH and FSH peaks and the time to attain peak concentration was not affected by the stage of gestation. The results of the present study point to a progressive decline in LH and FSH release responses to GnRH during the advancement of gestation in the buffalo. 相似文献
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Madan M. Kwatra Jolanda Schreurs Debra A. Schwinn Michael A. Innis Marc G. Caron Robert J. Lefkowitz 《Protein expression and purification》1995,6(6)
To obtain large quantities of pure human β2-adrenergic receptor (β2-AR) needed for structural studies, an efficient method for β2-AR purification was developed using a recombinant receptor with an eight amino acid epitope at its C-terminus. This epitope is recognized by KT3-monoclonal antibody. The epitope tagged β2-AR was expressed in Sf9 cells with a specific activity of 5–20 pmol/mg of membrane protein. The epitope-tagged and wild-type receptors had identical ligand binding properties. The tagged receptor was solubilized using dodecyl-β-maltoside with a quantitative yield. Solubilized epitope-tagged receptors were partially purified by KT3-mAb immunoaffinity in 60–70% yield. Further purification of the receptors on an alprenolol-affinity column resulted in a homogenous preparation with an overall yield of >30%. The purified receptor was concentrated to >1 mg/ml without loss of ligand binding activity. 相似文献
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Sachin Pannuri G. Ramakrishna Reddy Dianne McNeill Wayne R. Curtis 《Applied microbiology and biotechnology》1993,38(4):550-555
The effect of thiamine limitation in combination with fungal elicitation on sesquiterpene (solavetivone) production was studied in Agrobacterium-transformed hairy-root cultures of Hyoscyamus muticus as a potential means of manipulating the growth rate independent of phosphorus availability. Limiting the initial supply of thiamine did not affect the growth of these cultures compared to growth at the control level of thiamine (0.01 g/l). There was also no enhancement in sesquiterpene production when thiamine supply was limited. Serial culturing in thiamine-free media suggests that these root cultures are not strictly auxotrophic for thiamine, in contrast to previously published results for untransformed root culture. The effect of phosphate limitation combined with elicitation on the production of solavetivone was examined at constant media volume to provide a constant elicitor concentration and to eliminate feedback-inhibition effects. Limiting the initial supply of phosphate to elicited cultures resulted in a twofold increase in solavetivone production as compared to the elicitation at control media phosphate levels (1.1mm). Because growth was attenuated, production per unit cell mass increased 11-fold compared to the control. The effect of phosphate limitation on solavetivone production at constant cell mass and elicitor per root mass was studied. Limiting the initial supply of phosphate to elicited cultures under these conditions did not result in enhanced production of solavetivone. The initially observed enhanced production of solavetivone at limiting initial phosphate concentrations is therefore due to factors other than the growth rate or phosphate involvement in secondary metabolism.
Correspondence to: W. R. Curtis 相似文献
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A simplified technique of laparoscopy was developed for ovarian observation in the riverine buffalo, through a right paralumbar incision. The technique differed from previously described ones in that it involved only a single puncture and required no abdominal insufflation. A Hopkins 0 degrees forward viewing endoscope (5.5 mm x 500 mm) in combination with an endoscope sheath having a built-in instrument channel, and a long flexible forceps (630 mm) were used. Of the 23 observation attempts on 13 buffalo, 21 successful observations were conducted. Laparoscopies were performed using a combination of Xylazine, local infiltration and epidural anesthesia in a standing position. Six repeated observations were made within a 21-day period on 1 buffalo, with no postoperative complications. Observation of both left and right ovaries was possible through the same puncture. The technique was useful in buffalo to confirm ovarian structures which could not be determined with certainty through palpation per rectum. Our results suggest that the single puncture laparoscopy technique can be safely used for repeated ovarian examination in the water buffalo. 相似文献