Globular adiponectin ameliorates metabolic insulin resistance via AMPK-mediated restoration of microvascular insulin responses: Adiponectin improves microvascular insulin resistance

Hypoadiponectinaemia is closely associated with endothelial dysfunction and insulin resistance, and microvasculature plays a critical role in the regulation of insulin action in muscle. Here we tested whether adiponectin replenishment could improve metabolic insulin sensitivity in male rats fed a high-fat diet (HFD) via the modulation of microvascular insulin responses. Male Sprague–Dawley rats were fed either a HFD or low-fat diet (LFD) for 4 weeks. Small resistance artery myograph changes in tension, muscle microvascular recruitment and metabolic response to insulin were determined. Compared with rats fed a LFD, HFD feeding abolished the vasodilatory actions of globular adiponectin (gAd) and insulin on pre-constricted distal saphenous arteries. Pretreatment with gAd improved insulin responses in arterioles isolated from HFD rats, which was blocked by AMP-activated protein kinase (AMPK) inhibition. Similarly, HFD abolished microvascular responses to either gAd or insulin and decreased insulin-stimulated glucose disposal by ∼60%. However, supplementing gAd fully rescued insulin’s microvascular action and significantly improved the metabolic responses to insulin in HFD male rats and these actions were abolished by inhibition of either AMPK or nitric oxide production. We conclude that HFD induces vascular adiponectin and insulin resistance but gAd administration can restore vascular insulin responses and improve insulin’s metabolic action via an AMPK- and nitric oxide-dependent mechanism in male rats

Implementation of battery energy storage system for the electricity grid in Singapore

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2010.Cataloged from PDF version of thesis.Includes bibliographical references (p. 83-91).The market of grid-level electricity storage is growing rapidly, with a predicted market value of 1.6 billion in 2012 and 8.3 billion in 2016. Electrochemical storages such as lead-acid, nickel-cadmium, sodium-sulfur and lithium-ion batteries are candidates with high potential for grid-level implementations. Among them, sodium-sulfur battery appears to be suitable for energy application while lithium-ion battery has the capability to meet power application requirement well. However, models based on the local electricity market in Singapore show that in order to be economically efficient, the cost of sodium-sulfur battery system and lithium-ion battery system need to fall by 30% and 50%, respectively.by Zhenqi Wu.M.Eng

Inflammation-induced microvascular insulin resistance is an early event in diet-induced obesity

Endothelial dysfunction and vascular insulin resistance usually coexist and chronic inflammation engenders both. In the present study, we investigate the temporal relationship between vascular insulin resistance and metabolic insulin resistance. We assessed insulin responses in all arterial segments, including aorta, distal saphenous artery and the microvasculature, as well as the metabolic insulin responses in muscle in rats fed on a high-fat diet (HFD) for various durations ranging from 3 days to 4 weeks with or without sodium salicylate treatment. Compared with controls, HFD feeding significantly blunted insulin-mediated Akt (protein kinase B) and eNOS [endothelial nitric oxide (NO) synthase] phosphorylation in aorta in 1 week, blunted vasodilatory response in small resistance vessel in 4 weeks and microvascular recruitment in as early as 3 days. Insulin-stimulated whole body glucose disposal did not begin to progressively decrease until after 1 week. Salicylate treatment fully inhibited vascular inflammation, prevented microvascular insulin resistance and significantly improved muscle metabolic responses to insulin. We conclude that microvascular insulin resistance is an early event in diet-induced obesity and insulin resistance and inflammation plays an essential role in this process. Our data suggest microvascular insulin resistance contributes to the development of metabolic insulin resistance in muscle and muscle microvasculature is a potential therapeutic target in the prevention and treatment of diabetes and its related complications

Voltage-Gated Potassium Channel Kv13 Is Highly Expressed in Human Osteosarcoma and Promotes Osteosarcoma Growth

Scientific and Technologial Innovation Programs of of Nanjing Military Region, China [10MA077]Deregulation of voltage-gated potassium channel subunit Kv1.3 has been reported in many tumors. Kv1.3 promotes tumorigenesis by enhancing cell proliferation while suppressing apoptosis. However, the expression and function of Kv1.3 in osteosarcoma are unknown. In the present study, we detected the expression of Kv1.3 in human osteosarcoma cells and tissues by RT-PCR, Western blot and immunohistochemistry. We further examined cell proliferation and apoptosis in osteosarcoma MG-63 cells and xenografts following knockdown of Kv1.3 by short hairpin RNA (shRNA). We found that Kv1.3 was upregulated in human osteosarcoma. Knockdown of Kv1.3 significantly suppressed cell proliferation and increased apoptosis as demonstrated by enhanced cleavage of poly (ADP-ribose) polymerase (PARP) and the activation of Caspase-3/7. Furthermore, adenovirus delivered shRNA targeting Kv1.3 significantly inhibited the growth of MG-63 xenografts. Taken together, our results suggest that Kv1.3 is a novel molecular target for osterosarcoma therapy

Synthesis and Anti-Breast Cancer Evaluation of Novel N-(Guanidinyl)benzenesulfonamides

Scientific and Technologial Innovation Programs of the Nanjing military region, China [10MA077]A series of 4-(substituted)-N-(guanidinyl)benzenesulfonamides bearing biologically active pyrazole, pyrimidine and pyridine moieties were prepared and evaluated for their anticancer activity against human tumor breast cell line (MCF7). These sulfonamides showed promising activity with IC50 values ranging from 49.5 to 70.2 mu M. The structure-activity relationship of the synthesized compounds was studied. Interestingly, it was found that the most potent compounds in this study were the corresponding 2-cyanoacrylate 3, 3-oxobutanoate 4, pyrazole 6, pyridine 9 and pyrazole 13. Compounds 7 and 8 are nearly as active as Doxorubicin as reference drug with (IC50 values = 70.2, 68.1 mu M), while compounds 5, 10 and 11 exhibited a moderate activity

IMPURITY GETTERING BY PHOSPHOROUS DOPING IN SILICON WAFERS

Master'sMASTER OF SCIENCE IN ADVANCED MATERIALS FOR MICRO- & NANO- SYSTEM

Synthesis and characterization of pure CoSb3 nanoparticles of different Sb content

Effects of adding excess antimony during the polyol process for synthesizing CoSb3 compound have been studied in this project. It was found that with an initial atomic ratio Co:Sb = 1:4.5, the final sample after hot press contained a single CoSb3 phase. With higher initial Sb levels, extra free Sb phase approved in the final products as impurity. With increasing Sb atomic fraction, Seebeck coefficients of the sample was improved. However, the electrical resistivity values increased to a larger extent. As a result, excess Sb gave rise to lower power factor, and hence resulting in poorer thermoelectric performance.Bachelor of Engineering (Materials Engineering

Modeling circulation of train-set with multiple routing

Planning on utilization of train-set is one of the key tasks of transport organization for passenger dedicated railway in China. It also has strong relationships with timetable scheduling and operation plans at a station. To execute such a task in a railway hub pooling multiple railway lines, the characteristics of multiple routing for train-set is discussed in term of semicircle of train-sets' turnover. In programming the described problem, the minimum dwell time is selected as the objectives with special derive constraints of the train-set's dispatch, the connecting conditions, the principle of uniqueness for train-sets, and the first plus for connection in the same direction based on time tolerance σ. A compact connection algorithm based on time tolerance is then designed. The feasibility of the model and the algorithm is proved by the case study. The result indicates that the circulation model and algorithm about multiple routing can deal with the connections between the train-sets of multiple directions, and reduce the train's pulling in or leaving impact on the station's throat