61 research outputs found
Saturated free fatty acids and apoptosis in microvascular mesangial cells: palmitate activates pro-apoptotic signaling involving caspase 9 and mitochondrial release of endonuclease G
BACKGROUND: In type 2 diabetes, free fatty acids (FFA) accumulate in microvascular cells, but the phenotypic consequences of FFA accumulation in the microvasculature are incompletely understood. Here we investigated whether saturated FFA induce apoptosis in human microvascular mesangial cells and analyzed the signaling pathways involved. METHODS: Saturated and unsaturated FFA-albumin complexes were added to cultured human mesangial cells, after which the number of apoptotic cells were quantified and the signal transduction pathways involved were delineated. RESULTS: The saturated FFA palmitate and stearate were apoptotic unlike equivalent concentrations of the unsaturated FFA oleate and linoleate. Palmitate-induced apoptosis was potentiated by etomoxir, an inhibitor of mitochondrial β-oxidation, but was prevented by an activator of AMP-kinase, which increases fatty acid β-oxidation. Palmitate stimulated an intrinsic pathway of pro-apoptotic signaling as evidenced by increased mitochondrial release of cytochrome-c and activation of caspase 9. A caspase 9-selective inhibitor blocked caspase 3 activation but incompletely blocked apoptosis in response to palmitate, suggesting an additional caspase 9-independent pathway. Palmitate stimulated mitochondrial release of endonuclease G by a caspase 9-independent mechanism, thereby implicating endonuclease G in caspase 9-indpendent regulation of apoptosis by saturated FFA. We also observed that the unsaturated FFA oleate and linoleate prevented palmitate-induced mitochondrial release of both cytochrome-c and endonuclease G, which resulted in complete protection from palmitate-induced apoptosis. CONCLUSIONS: Taken together, these results demonstrate that palmitate stimulates apoptosis by evoking an intrinsic pathway of proapoptotic signaling and identify mitochondrial release of endonuclease G as a key step in proapoptotic signaling by saturated FFA and in the anti-apoptotic actions of unsaturated FFA
Excavation of Silenced Voices: (Re)visiting Menka Shivdasani’s Frazil through the Modern Feminist Discourse of Indian Writing in English
The postmodernist phase of Indian English writing is characterized by the voices of many strong women expressing a feminist exploration of alternative discourses in women’s writing which are distinguished from the patriarchal framework of literary discourse. Along with Kamala Das, Meena Alexander, Imtiaz Dharkar, and Eunice de Souza, Menka Shivdasani is an active voice in contemporary Indian English poetry. Shivdasani is a prolific poet who has written poetry on various social, cultural, religious, and personal issues. Her four poetry collections include Nirvana at Ten Rupees (1990), Stet (2001), Safe House (2015), and Frazil (2018). Through her poetry, she has endeavored to deconstruct the constructed nature of women in patriarchal societies. However, in literary criticism, she has not been explored in detail; thus, Shivdasani deserves to be better known. She is truly an unsung voice in Indian English poetry because of her poetic excellence. The present paper will attempt to (re)visit Shivdasani’s work with particular reference to her recent poetry collection Frazil. The themes it depicts are women’s sensibilities, man-woman relationships, domesticity, myth, culture, religion, memory, loss, and the anxiety of city life. Therefore, the paper will analyze the thematic and structural aspects of her poetry, with assistance from the work of Menka Shivdasani, to move Shivdasani onto the center stage in the postmodernist phase of Indian writing in English
A field survey on abundance of biofuel plant species in Alur Taluk of Hassan District, Karnataka, India
There are more than 150 species of plants that could be used for biofuel production. Important among them in Karnataka are Honge (Pongamia pinnata), Neem (Azadiracta indica), Hippe (Maduca latifolia), Jatropha (Jatropha curcas) and Simarouba (Simarouba glauca). A field survey was conducted in Alur taluk of Hassan District, (75º 9´ to 12º 9´) Karnataka, to know the abundance of biofuel plant species and to estimate resource availability for extraction of oil and production of Biodiesel. The number of Households in the study villages ranged from 120 to 600 with population ranging from 60 to 2,500 and number of productive Honge trees varied from 3 to 2,000 trees/village yielding on an average around 2 to 10 kg seeds per tree with very few Neem and Hippe trees but Jatropha plants were present in every village with very low yielding potential (50-100 grams per plant). Majority of the biofuel plants present were in vegetative stage and few were yielding. The yield of biofuel plant species is quite promising and the process of seed for oil extraction is possible and provides employment to the rural youth in the taluk. The substantial demand has been noticed in Alur taluk for Honge and Neem oil cakes and the availability is meager. Substantial scope is available for growing of biofuel trees, seed collection, processing and marketing providing additional employment to rural people. There is an increased demand for the biofuels and by utilizing the available resources the rural youth can start their own enterprise
Comparative study between histological changes in placenta from pre-eclampsia cases and normal pregnancy with special reference to cytotrophoblastic cell hyperplasia, villous stromal fibrosis and fibrinoid necrosis
Background: Placenta is a vital organ and the most accurate record of the infant’s prenatal experience. Pregnancy complications like hypertension significantly affect the placenta. Thus there is a need for thorough examination of it. Therefore the present study is dedicated to see the histological changes in placenta of pre-eclampsia with special reference to cytotrophoblastic cell hyperplasia, villous stromal fibrosis and fibrinoid necrosis and compared it with that of normal placenta.Methods: Total 60 placentas were collected (30 from pre-eclampsia and 30 from normal pregnancy). Results were expressed in percentage after counting 100 villi. Data analysis has been done using Graphpad InStat 3 version and data is significant when p – value is <0.05.Results: Mean no. of cytotrophoblastic cell hyperplasia, villous stromal fibrosis and fibrinoid necrosis in normal placenta are 10.1±5.01, 2.26±1.56 and 2.84±1.4 respectively and those in pre-eclampsia placenta are 36.82±16.15, 28.16± 34.42 and 8.22±1.44 respectively which are highly significant ( p-value <0.001).Conclusions: There is significant increase in number of cytotrophoblastic cell hyperplasia, villous stromal fibrosis and areas fibrinoid necrosis in placenta from pre-eclampsia cases than that of normal placenta. These changes may be due to vascular insufficiency which is usually occurring in pre-eclampsia
Acoustical and optical properties of binary liquid mixtures: A comparative study
Ultrasonic velocity in conjunction with density plays a major role in determining a number of key thermophysical parameters which are used in multifarious industrial applications. In the present investigation, a comparative study has been carried out employing a number of predictive approaches for evaluating ultrasonic velocity for 82 binary systems and refractive index for 76 binary systems, taking AAPD as the criterion for their predictive capability. Some very important findings emerge which will be beneficial to researchers in this, and allied fields of work
Stable ensemble brightness from nitrogen vacancy centers in nanodiamonds through optimized surface composition
Stable ensemble emission from nitrogen vacancy (NV) centers in nanodiamonds (NDs) is highly desirable for diverse areas ranging from bio-imaging to quantum optics. The uniqueness of NV centers lies in their opto-spin properties like energy level structure, emission range (620-850 nm) and optical spin polarization. The host matrix (NDs), however, put some limitation on the photo-physical properties of these color centers. One of the major issues is surface proximity (where high concentration of defects are present) of NV centers. The NV centers being highly sensitive to the neighboring environment are unstable in such circumstances. The surface of NDs mainly exhibit non-diamond carbon which is well-known quencher of emission due to NV centers. The surface composition for desirable photo-physical properties of NV centers is still unknown. Here, we have systemically studied the effect of oxidation time at low oxidation temperature (450 oC) on the selective removal of sp2 carbon, aqueous dispersion of NDs and emission collection due to NV centers at ensemble level. Among different air oxidations, heat treatment at 450 oC at residual time of 8 hours has been found to be suitable air oxidation conditions for the enhancement of brightness and ensemble photo-stability of NV centers
Effect of fibre orientation on mechanical properties of carbon fibre composites
The research aims to investigate the carbon fibre composite laminate for effect of their layer configuration including their number and relative orientation of fibre angles on their mechanical properties and its consistency with the results obtained from simulated data using finite element analysis (FEA) on mechanical properties. The laminate composite with four types of fiber layer orientations were prepared using total eight layers including unidirectional and cross ply layers with different orientations. The flexural properties of the samples were evaluated. The results of experiments found consistent with the simulated data and it indicates that the fibre orientations and its layer sequence influence the characteristics of laminate composites. The composite with 0 orientated unidirectional fibre layers shows maximum flexural strength. The flexural strain is higher for laminate composite having layers with cross plies (45° fibre orientations). The different position of cross ply in the sequence shows variations in flexural properties because the typical nature of the three point bending flexural test of laminate composite where top side layers are under compression and bottom side layers are under tension
Stable ensemble brightness from nitrogen vacancy centers in nanodiamonds through optimized surface composition
1071-1079Stable ensemble emission from nitrogen vacancy (NV) centers in nanodiamonds (NDs) is highly desirable for diverse areas ranging from bio-imaging to quantum optics. The uniqueness of NV centers lies in their opto-spin properties like energy level structure, emission range (620-850 nm) and optical spin polarization. The host matrix (NDs), however, put some limitation on the photo-physical properties of these color centers. One of the major issues is surface proximity (where high concentration of defects are present) of NV centers. The NV centers being highly sensitive to the neighboring environment are unstable in such circumstances. The surface of NDs mainly exhibit non-diamond carbon which is well-known quencher of emission due to NV centers. The surface composition for desirable photo-physical properties of NV centers is still unknown. Here, we have systemically studied the effect of oxidation time at low oxidation temperature (450 oC) on the selective removal of sp2 carbon, aqueous dispersion of NDs and emission collection due to NV centers at ensemble level. Among different air oxidations, heat treatment at 450 oC at residual time of 8 hours has been found to be suitable air oxidation conditions for the enhancement of brightness and ensemble photo-stability of NV centers
Navigating the Contested Terrain of Teacher Education Policy and Practice: Authors Respond to SCALE
Stanford Center for Assessment, Learning, and Equity (SCALE) provided a commentary on the manuscripts in the first part of this special issue, which highlighted the benefits of edTPA and the necessity for such assessment programs to improve teacher education and strengthen teaching practices. In turn, the authors responded to the SCALE commentary. The authors’ responses raise concerns about equity, fairness, and unintended consequences of teacher performance assessments. These responses highlight the need for continued dialogue on ways to improve teacher education and strengthen the teaching profession
Effect of fibre orientation on mechanical properties of carbon fibre composites
1100-1103The research aims to investigate the carbon fibre composite laminate for effect of their layer configuration including their number and relative orientation of fibre angles on their mechanical properties and its consistency with the results obtained from simulated data using finite element analysis (FEA) on mechanical properties. The laminate composite with four types of  fiber layer orientations were prepared using total eight layers including unidirectional and cross ply layers with different orientations. The flexural properties of the samples were evaluated. The results of experiments found consistent with the simulated data and it indicates that the fibre orientations and its layer sequence influence the characteristics of laminate composites. The composite with 0° orientated unidirectional fibre layers shows maximum flexural strength. The flexural strain is higher for laminate composite having layers with cross plies (45° fibre orientations). The different position of cross ply in the sequence shows variations in flexural properties because the typical nature of the three point bending flexural test of laminate composite where top side layers are under compression and bottom side layers are under tension
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