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41.
42.
Naiomy D. Rios-Arce Andrew Dagenais Derrick Feenstra Brandon Coughlin Ho Jun Kang Susanne Mohr Laura R. McCabe Narayanan Parameswaran 《Journal of cellular physiology》2020,235(3):2350-2365
Type-1 diabetes (T1D) increases systemic inflammation, bone loss, and risk for bone fractures. Levels of the anti-inflammatory cytokine interleukin-10 (IL-10) are decreased in T1D, however their role in T1D-induced osteoporosis is unknown. To address this, diabetes was induced in male IL-10 knockout (KO) and wild-type (WT) mice. Analyses of femur and vertebral trabecular bone volume fraction identified bone loss in T1D-WT mice at 4 and 12 weeks, which in T1D-IL-10-KO mice was further reduced at 4 weeks but not 12 weeks. IL-10 deficiency also increased the negative effects of T1D on cortical bone. Osteoblast marker osterix was decreased, while osteoclast markers were unchanged, suggesting that IL-10 promotes anabolic processes. MC3T3-E1 osteoblasts cultured under high glucose conditions displayed a decrease in osterix which was prevented by addition of IL-10. Taken together, our results suggest that IL-10 is important for promoting osteoblast maturation and reducing bone loss during early stages of T1D. 相似文献
43.
Probiotics are a cultured product or live microbial feed supplement, which beneficially affects the host by improving its intestinal balance and health of the host. In the present study an attempt was made to study the effect of Pseudomonas aeruginosa (MICC 741) as a colour enhancing probiont in addition to growth and disease resistance in the ornamental cichlid, Pseudotropheus lombardoi. The experimental fishes were fed with different concentrations of P. aeruginosa. Incorporation of P. aeruginosa to the maximum of 30 mL (103 CFU/mL) resulted in the gain of carotenoid pigment to the tune of 400 % over the control (p < 0.05) which again showed a significant increase in the growth rate of P. lombardoi. Disease resistance against the pathogens Vibrio parahaemolyticus and Bacillus cereus which were isolated from a diseased P. lombardoi were measured by zone of inhibition. Pseudomonas aeruginosa was found to be significantly effective in controlling both the pathogens. The investigation on P. aeruginosa proved that it not only improves the pigmentation, but also promotes growth and immunity to P. lombardoi. 相似文献
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Shilpa Bhatnagar Naveen Chaudhary Deepshikha Pande Katare S. K. Jain 《Protoplasma》2013,250(4):919-929
Lung cancer is one of the most common malignant neoplasms all over the world. Smoking and a number of constituents of tobacco are responsible for development of lung tumours; however, the deleterious effects of tobacco-derived carcinogen, nitrosamine 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamine ketone (NNK)) remain unmatched. We report the development of a novel rodent model by administering multiple doses of NNK to male Wistar rats and feeding them with high-fat and low-protein diet. Tumour cells in lungs were observed in approximately 98 % rats after 8 months of NNK treatment, as evident by histopathological analysis. This rodent model showed slow progression of lung tumours which has helped us to assess early indicators of oxidative damage in lungs by studying the levels of lipid peroxidation and antioxidant parameters. LPO was elevated by 46.94 %, SOD, CAT, GSH and GR activity was decreased by 48.67 %, 22.04 %, 21.46 % and 20.85 %, respectively in serum of NNK treated rats when compared with control. These findings suggest that increased oxidative stress can represent a risk factor for the development of chronic disease in early future. This new animal model is an attempt to greatly facilitate studies of the pathophysiology, biochemistry and therapy of lung cancer. 相似文献
46.
Myung-Chul Chung Aarthi Narayanan Taissia G. Popova Fatah Kashanchi Charles L. Bailey Serguei G. Popov 《Biochemical and biophysical research communications》2013,430(1):125-130
Bacillus anthracis, a causative agent of anthrax, is able to germinate and survive within macrophages. A recent study suggested that B. anthracis-derived nitric oxide (bNO) is a key aspect of bacterial defense that protects bacterial DNA from oxidative burst in the macrophages. However, the virulent effect of bNO in host cells has not been investigated. Here, we report that bNO contributes macrophage killing by S-nitrosylation of bioenergetic-relating proteins within mitochondria. Toxigenic Sterne induces expression of the bnos gene and produces bNO during early stage of infection. Nitroso-proteomic analysis coupled with a biotin-switch technique demonstrated that toxigenic infection induces protein S-nitrosylation in B. anthracis-susceptible RAW264.7. For each target enzyme tested (complex I, complex III and complex IV), infection by B. anthracis Sterne caused enzyme inhibition. Nω-nitro-l-arginine methyl ester, a NO synthase inhibitor, reduced S-nitrosylation and partially restored cell viability evaluated by intracellular ATP levels in macrophages. Our data suggest that bNO leads to energy depletion driven by impaired mitochondrial bioenergetic machinery that ultimately contributes to macrophage death. This novel mechanism of anthrax pathogenesis may offer specific approach to the development of therapeutics. 相似文献
47.
Naveen Admala Reddy Gopinath Adusumilli Raghu Devanna Rohra G Mayur Saravanan Pichai Sharmila Arujnan 《Indian journal of human genetics》2013,19(4):459-464
INTRODUCTION:
Non-syndromic tooth agenesis is a congenital anomaly with significant medical, psychological, and social ramifications. There is sufficient evidence to hypothesize that locus for this condition can be identified by candidate genes.AIM OF THE STUDY:
The aim of this study was to test whether MSX1 671 T > C gene variant was involved in etiology of non-syndromic tooth agenesis in Raichur patients.MATERIALS AND METHODS:
Blood samples were collected with informed consent from 50 subjects having non-syndromic tooth agenesis and 50 controls. Genomic deoxyribonucleic acid (DNA) was extracted from the blood samples, polymerase chain reaction (PCR) was performed, and restriction fragment length polymorphism (RFLP) was performed for digestion products that were evaluated.RESULTS:
The results showed positive correlation between MSX1671 T > C gene variant and non-syndromic tooth agenesis in Raichur patients.CONCLUSION:
MSX1 671 T > C gene variant may be a good screening marker for non-syndromic tooth agenesis in Raichur patients. 相似文献48.
49.
Jaymin C. Patel Jenna Oberstaller Maniphet Xayavong Jothikumar Narayanan Jeremy D. DeBarry Ganesh Srinivasamoorthy Leopoldo Villegas Ananias A. Escalante Alexandre DaSilva David S. Peterson John W. Barnwell Jessica C. Kissinger Venkatachalam Udhayakumar Naomi W. Lucchi 《PloS one》2013,8(1)
Plasmodium vivax infections remain a major source of malaria-related morbidity and mortality. Early and accurate diagnosis is an integral component of effective malaria control programs. Conventional molecular diagnostic methods provide accurate results but are often resource-intensive, expensive, have a long turnaround time and are beyond the capacity of most malaria-endemic countries. Our laboratory has recently developed a new platform called RealAmp, which combines loop-mediated isothermal amplification (LAMP) with a portable tube scanner real-time isothermal instrument for the rapid detection of malaria parasites. Here we describe new primers for the detection of P. vivax using the RealAmp method. Three pairs of amplification primers required for this method were derived from a conserved DNA sequence unique to the P. vivax genome. The amplification was carried out at 64°C using SYBR Green or SYTO-9 intercalating dyes for 90 minutes with the tube scanner set to collect fluorescence signals at 1-minute intervals. Clinical samples of P. vivax and other human-infecting malaria parasite species were used to determine the sensitivity and specificity of the primers by comparing with an 18S ribosomal RNA-based nested PCR as the gold standard. The new set of primers consistently detected laboratory-maintained isolates of P. vivax from different parts of the world. The primers detected P. vivax in the clinical samples with 94.59% sensitivity (95% CI: 87.48–98.26%) and 100% specificity (95% CI: 90.40–100%) compared to the gold standard nested-PCR method. The new primers also proved to be more sensitive than the published species-specific primers specifically developed for the LAMP method in detecting P. vivax. 相似文献
50.
The silk protein from the web of Orthaga exvinacea was isolated, purified, and casted into films. This film was treated separately with methanol, acetone, ethyl acetate, and isopropyl alcohol in 50 % concentration for about 30 min. The treated films were thus dried in a desiccator and subjected to FTIR and TG-DTA analysis. The structural studies revealed that the organic solvents induce conformatory changes in the protein film, especially the most sensitive amide I (1650 cm?1) band. This band had shifted to lower wavenumber (1633–1636 cm?1). Furthermore, the conformatory characteristics associated with amide I band also changed from random coil to β-sheet. Generally, β-sheet contributes strength to the protein film. Among the treated films, film treated with acetone showed much thermal stability. Moreover, the film treated with methanol had shown two different temperatures of maximum degradation. It is concluded that in addition to β-sheet content, various other factors such as various processing conditions and structural organization of protein may influence the stability of the films. 相似文献