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81.
Anjana Jajoo Sonal Mathur Pooja Mehta Miho Yoshoika Suleyman I. Allakhverdiev Yasusi Yamamoto 《Journal of bioenergetics and biomembranes》2010,42(1):47-53
Chloride is an indispensable factor for the functioning of oxygen evolving complex (OEC) and has protective and activating
effects on photosystem II. In this study we have investigated mainly by EPR, the properties of chloride-sufficient, chloride-deficient
and chloride-depleted thylakoid membranes and photosystem II enriched membranes from spinach. The results on the effects of
different chloride depletion methods on the structural and functional aspects of photosystem II showed that chloride-depletion
by treating PS II membranes with high pH is a relatively harsh way causing a significant and irreparable damage to the PS
II donor side. Damage to the acceptor side of PS II was recovered almost fully in chloride-deficient as well as chloride-depleted
PS II membranes. 相似文献
82.
Jagmohan S. Negi Pramod Singh Geeta J. Nee Pant Mohan S. Maniyari Rawat H. K. Pandey 《Biological trace element research》2010,135(1-3):275-282
The present study was carried out to determine the accumulation and variation of trace elements in roots and leaves of Asparagus racemosus collected from four different altitudes in Uttarakhand, India, by atomic absorption spectroscopy. The metals investigated were Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li. The concentration level of Fe was found to be highest at an altitude of 2,250 m, whereas the level of Cu was lowest. The maximum concentrations of Zn, Cu, Mn, Fe, Co, Na, K, Ca, and Li were found to be 165.0?±?3.2, 34.0?±?0.5, 84.0?±?0.7, 2,040.0?±?0.3, 122.0?±?1.5, 745.0?±?0.3, 13,260.0?±?3.5, 6,153.0?±?1.6, and 58.0?±?3.8 mg/kg, respectively. 相似文献
83.
Jagmohan S. Negi Pramod Singh Geeta J. nee Pant Mohan S. Maniyari Rawat 《Biological trace element research》2010,138(1-3):300-306
Variations of micro- and macrominerals concentration in Swertia speciosa were determined by atomic absorption spectroscopy. The mineral elements showed significant changes in roots and leaves collected from different altitudes. Among all the elements, highest concentration (more than 2,000 mg/kg) of Ca and K were recorded in S. speciosa and the concentration of other elements analyzed in the study decreased in the order Fe>Na>Zn>Co>Li>Cu>Mn. 相似文献
84.
85.
The effect of population size, redox potential, exogenous ATP and complexing agents on Cu uptake by free and immobilized cyanobacteriumNostoc calcicola
Bréb. has been studied. Cu uptake was regulated by the population size. In such comparisons, the immobilized cells had a greater
longevity. Low pH conditions enhanced Cu uptake. Exogenous ATP (10 μmol/L) supplied to dark-grown free and immobilized cells
did not support Cu uptake to the extent of light-grown cells. Experiments involving natural as well as synthetic complexing
agents clearly established the superiority of soil extract and spent medium over EDTA (10 μmol/L), in sequestering Cu in free
as well as immobilized cells. 相似文献
86.
87.
Anjana Singh Narendiran Rajasekaran Bettina Hartenstein Sibylle Szabowski Mieczyslaw Gajda Peter Angel Rolf Br?uer Harald Illges 《Arthritis research & therapy》2013,15(6):R222
Introduction
Matrix metalloproteinases (MMPs) are important in tissue remodelling. Here we investigate the role of collagenase-3 (MMP-13) in antibody-induced arthritis.Methods
For this study we employed the K/BxN serum-induced arthritis model. Arthritis was induced in C57BL/6 wild type (WT) and MMP-13-deficient (MMP-13–/–) mice by intraperitoneal injection of 200 μl of K/BxN serum. Arthritis was assessed by measuring the ankle swelling. During the course of the experiments, mice were sacrificed every second day for histological examination of the ankle joints. Ankle sections were evaluated histologically for infiltration of inflammatory cells, pannus tissue formation and bone/cartilage destruction. Semi-quantitative PCR was used to determine MMP-13 expression levels in ankle joints of untreated and K/BxN serum-injected mice.Results
This study shows that MMP-13 is a regulator of inflammation. We observed increased expression of MMP-13 in ankle joints of WT mice during K/BxN serum-induced arthritis and both K/BxN serum-treated WT and MMP-13–/– mice developed progressive arthritis with a similar onset. However, MMP-13–/– mice showed significantly reduced disease over the whole arthritic period. Ankle joints of WT mice showed severe joint destruction with extensive inflammation and erosion of cartilage and bone. In contrast, MMP-13–/– mice displayed significantly decreased severity of arthritis (50% to 60%) as analyzed by clinical and histological scoring methods.Conclusions
MMP-13 deficiency acts to suppress the local inflammatory responses. Therefore, MMP-13 has a role in the pathogenesis of arthritis, suggesting MMP-13 is a potential therapeutic target. 相似文献88.
Catherine L. Kennedy Danielle J. Smith Dena Lyras Anjana Chakravorty Julian I. Rood 《PLoS pathogens》2009,5(7)
Programmed necrosis is a mechanism of cell death that has been described for neuronal excitotoxicity and ischemia/reperfusion injury, but has not been extensively studied in the context of exposure to bacterial exotoxins. The α-toxin of Clostridium septicum is a β-barrel pore-forming toxin and a potent cytotoxin; however, the mechanism by which it induces cell death has not been elucidated in detail. We report that α-toxin formed Ca2+-permeable pores in murine myoblast cells, leading to an increase in intracellular Ca2+ levels. This Ca2+ influx did not induce apoptosis, as has been described for other small pore-forming toxins, but a cascade of events consistent with programmed necrosis. Ca2+ influx was associated with calpain activation and release of cathepsins from lysosomes. We also observed deregulation of mitochondrial activity, leading to increased ROS levels, and dramatically reduced levels of ATP. Finally, the immunostimulatory histone binding protein HMGB1 was found to be released from the nuclei of α-toxin-treated cells. Collectively, these data show that α-toxin initiates a multifaceted necrotic cell death response that is consistent with its essential role in C. septicum-mediated myonecrosis and sepsis. We postulate that cellular intoxication with pore-forming toxins may be a major mechanism by which programmed necrosis is induced. 相似文献
89.
Cadmium and lead interactive effects on oxidative stress and antioxidative responses in rice seedlings 总被引:7,自引:0,他引:7
Rajneesh Kumar Srivastava Poonam Pandey Ritika Rajpoot Anjana Rani R. S. Dubey 《Protoplasma》2014,251(5):1047-1065
Interactive effects of two heavy metal pollutants Cd and Pb in the growth medium were examined on their uptake, production of reactive oxygen species (ROS), induction of oxidative stress and antioxidative defence responses in Indica rice (Oryza sativa L.) seedlings. When rice seedlings in sand culture were exposed to 150 μM Cd (NO3)2 or 600 μM Pb (CH3COO)2 individually or in combination for 8–16 days, a significant reduction in root/shoot length, fresh weight, relative water content, photosynthetic pigments and increased production of ROS (O2˙? and H2O2) was observed. Both Cd and Pb were readily taken up by rice roots and localisation of absorbed metals was greater in roots than in shoots. When present together in the growth medium, uptake of both the metals Cd and Pb declined by 25–40 %. Scanning electron microscope (SEM) imaging of leaf stomata revealed that Pb caused more distortion in the shape of guard cells than Cd. Dithizone staining of roots showed localisation of absorbed Cd on root hairs and epidermal cells. Both Cd and Pb caused increased lipid peroxidation, protein carbonylation, decline in protein thiol and increase in non-protein thiol. The level of reduced forms of non-enzymic antioxidants glutathione (GSH) and ascorbate (AsA) and their redox ratios (GSH/AsA) declined, whereas the activities of antioxidative enzymes superoxide dismutase (SOD) and guaiacol peroxidase (GPX) increased in metal treated seedlings compared to controls. In-gel activity staining also revealed increased intensities of SOD and GPX isoforms with metal treatments. Catalase (CAT) activity increased during early days (8 days) of metal exposure and declined by 16 days. Results suggest that oxidative stress is an important component in expression of Cd and Pb toxicities in rice, though uptake of both metals gets reduced considerably when present together in the medium. 相似文献
90.
Anjana Sharma Sachin Kumar Chandraker Manisha Bharti 《Indian journal of microbiology》2007,47(3):233-240
Sixteen isolates of Nontubercular Mycobacteria species were isolated from drinking water supply of some educational institutes
in Jabalpur during July 2006 and were identified by biochemical test, thin layer chromatography (TLC) and high performance
liquid chromatography (HPLC) analysis and PRA ( PCR restriction enzyme analysis) of rpoB gene. Out of 21 water samples total
16 isolates of nontuberculous mycobacteria were identified, as M. terrae (6), M. szulgai (4), M. gordonae (3), and one each as M. malmoense, M. kansasii, and M. gastri. 相似文献