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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
2.
The light-growth response of Phycomyces has been studied further with the sum-of-sinusoids method in the framework of the Wiener theory of nonlinear system identification. The response was treated as a black box with the logarithm of light intensity as the input and elongation rate as the output. The nonlinear input-output relation of the light-growth response can be represented mathematically by a set of weighting functions called kernels, which appear in the Wiener intergral series. The linear (first-order) kernels of wild type, and of single and double mutants affected in genes madA to madG were determined previously with Gaussian white noise test stimuli, and were used to investigate the interactions among the products of these genes (R.C. Poe, P. Pratap, and E.D. Lipson. 1986. Biol. Cybern. 55:105.). We have used the more precise sum-of-sinusoids method to extend the interaction studies, including both the first- and second-order kernels. Specifically, we have investigated interactions of the madH ("hypertropic") gene product with the madC ("night blind") and madG ("stiff") gene products. Experiments were performed on the Phycomyces tracking machine. The log-mean intensity of the stimulus was 6 x 10(-2) W m-2 and the wavelength was 477 nm. The first- and second-order kernels were analyzed in terms of nonlinear kinetic models.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
Stem segments of adult plants of Ficus religiosa L. cultured on MS medium containing 1.0 mg/l 2,4-D produced callus. Shoots were regenerated when the induced calli were transferred to medium supplemented with 0.05 to 2.0 mg/l BAP. Callus derived shoots produced roots and developed into plantlets when transferred to medium supplemented with 1.0 mg/l NAA.Abbreviations MS
Murashige and Skoog (1962)
- BAP
6-benzylaminopurine
- NAA
naphthaleneacetic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid 相似文献
4.
Hilal Bashir Sanpreet Singh Raghwendra Pratap Singh Javed N. Agrewala Rashmi Kumar 《Aging cell》2023,22(6):e13838
The old age-related loss of immune tolerance inflicts a person with a wide range of autoimmune and inflammatory diseases. Dendritic cells (DCs) are the sentinels of the immune system that maintain immune tolerance through cytokines and regulatory T-cells generation. Aging disturbs the microbial composition of the gut, causing immune system dysregulation. However, the vis-à-vis role of gut dysbiosis on DCs tolerance remains highly elusive. Consequently, we studied the influence of aging on gut dysbiosis and its impact on the loss of DC tolerance. We show that DCs generated from either the aged (DCOld) or gut-dysbiotic young (DCDysbiotic) but not young (DCYoung) mice exhibited loss of tolerance, as evidenced by their failure to optimally induce the generation of Tregs and control the overactivation of CD4+ T cells. The mechanism deciphered for the loss of DCOld and DCDysbiotic tolerance was chiefly through the overactivation of NF-κB, impaired frequency of Tregs, upregulation in the level of pro-inflammatory molecules (IL-6, IL-1β, TNF-α, IL-12, IFN-γ), and decline in the anti-inflammatory moieties (IL-10, TGF-β, IL-4, IDO, arginase, NO, IRF-4, IRF-8, PDL1, BTLA4, ALDH2). Importantly, a significant decline in the frequency of the Lactobacillus genus was noticed in the gut. Replenishing the gut of old mice with the Lactobacillus plantarum reinvigorated the tolerogenic function of DCs through the rewiring of inflammatory and metabolic pathways. Thus, for the first time, we demonstrate the impact of age-related gut dysbiosis on the loss of DC tolerance. This finding may open avenues for therapeutic intervention for treating age-associated disorders with the Lactobacillus plantarum. 相似文献
5.
Employing a simple one-step sucrose gradient fractionation method, gastric mucosal membrane of Syrian hamster was prepared and demonstrated to be specifically enriched in H+,K+-ATPase activity. The preparation is practically devoid of other ATP hydrolyzing activity and contains high K+-stimulated ATPase, activity of at least 4–5 fold compared to basal ATPase activity. The H+,K+-ATPase showed hydroxylamine-sensitive phosphorylation and K+-dependent dephosphorylation of the phospho-enzyme, characteristic inhibition by vanadate, omeprazole and SCH 28080, and nigericin-reversible K+-dependent H+-transport — properties characteristic of gastric proton pump One notable difference with H+,K+-ATPase of other species has been the observation of valinomycin-independent H+ transport in such membrane vesicles. It is proposed that such H+,K+-ATPase-rich hamster gastric mucosal membrane preparation might provide a unique model to study physiological aspects of H+,K+-ATPase-function in relation to HCl secretion. 相似文献
6.
- The effect of dietary protein levels on the proteolytic activity in the intestines of the air-breathing fish, Clarias batrachus (Linn.) has been studied
- Activity of proteolytic enzymes increased significantly in fishes maintained with a 50% protein diet from those maintained with a 25% protein diet; still higher dietary protein percentage showed no further stimulation of enzyme activity.
- In a study on the determination of sub-cellular localisation, it has been found that protease activity is more prominent in lysosomes than in other organelles of the cell.
- A sixty fold purification of alkaline protease from the intestine of Clarias batrachus has been achieved by ion exchange chromatography on DEAE cellulose which has been further checked by polyacrylamide gel electrophoresis.
7.
The light-growth response of Phycomyces has been studied with the sum-of-sinusoids method of nonlinear system identification (Victor, J.D., and R.M. Shapley, 1980, Biophys. J., 29:459). This transient response of the sporangiophore has been treated as a black-box system with one input (logarithm of the light intensity, I) and one output (elongation rate). The light intensity was modulated so that log I, as a function of time, was a sum of sinusoids. The log-mean intensity was 10(-4) W m-2 and the wavelength was 477 nm. The first- and second-order frequency kernels, which represent the linear and nonlinear behavior of the system, were obtained from the Fourier transform of the response at the appropriate component and combination frequencies. Although the first-order kernel accounts for most of the response, there remains a significant nonlinearity beyond the logarithmic transducer presumed to occur at the input of the sensory transduction chain. From the analysis of the frequency kernels, we have derived a dynamic nonlinear model of the light-growth response system. The model consists of a nonlinear subsystem followed by a linear subsystem. The model parameters were estimated from a combined nonlinear least-squares fit to the first- and second-order frequency kernels. 相似文献
8.
Kulsoom Zahra Sandeep Patel Tulika Dey Uma Pandey Surendra Pratap Mishra 《Biochemistry and Biophysics Reports》2021
Cervical cancer is the second most common cause of cancer-related death among women worldwide, especially in developing countries. Oxidative stress has been associated with cervical cancer. Many studies demonstrated that the low level of antioxidants induces the production of free radicals that cause lipid peroxidation, DNA, and protein damage leading to mutations that favors malignant transformation. This is a case-control institutional study conducted to evaluate the level of oxidative stress in cervical cancer patients and the age-matched healthy controls. We measured level of TBARS expressed as MDA, activity of SOD and GSH level by the spectrophotometric method, and level of 8-OHdG was estimated using a competitive sandwich ELISA assay. Our results showed a significant increase in the level of lipid peroxidation in group IV when compared to the control, group II and group III (p < 0.001). The activity of SOD was also significantly higher in group IV when compared to the control group (p < 0.001), group II (p < 0.001), and group III (p < 0.001). The level of GSH was also significantly lower in group IV when compared to the control group (p < 0.01), group II (p < 0.01), and group III (p < 0.01). The level of 8-OHdG was significantly higher in group IV than in the other groups (p < 0.01). The results suggest that oxidative stress is involved in the pathogenesis of cervical cancer, which is demonstrated by an increased level of lipid peroxidation and higher levels of 8-OHdG and an altered antioxidant defense system. 相似文献
9.
Huma N Shankar P Kushwah J Bhushan A Joshi J Mukherjee T Raju S Purohit HJ Kalia VC 《Journal of microbiology and biotechnology》2011,21(10):1001-1011
To explore bacterial diversity for elucidating genetic variability in acylhomoserine lactone (AHL) lactonase structure, we screened 800 bacterial strains. It revealed the presence of a quorum quenching (QQ) AHL-lactonase gene (aiiA) in 42 strains. These 42 strains were identified using rrs (16S rDNA) sequencing as Bacillus strains, predominantly B. cereus. An in silico restriction endonuclease (RE) digestion of 22 AHL lactonase gene (aiiA) sequences (from NCBI database) belonging to 9 different genera, along with 42 aiiA gene sequences from different Bacillus spp. (isolated here) with 14 type II REs, revealed distinct patterns of fragments (nucleotide length and order) with four REs; AluI, DpnII, RsaI, and Tru9I. Our study reflects on the biodiversity of aiiA among Bacillus species. Bacillus sp. strain MBG11 with polymorphism (115Alanine > Valine) may confer increased stability to AHL lactonase, and can be a potential candidate for heterologous expression and mass production. Microbes with ability to produce AHL-lactonases degrade quorum sensing signals such as AHL by opening of the lactone ring. The naturally occurring diversity of QQ molecules provides opportunities to use them for preventing bacterial infections, spoilage of food, and bioremediation. 相似文献
10.