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101.
Tong Y Claiborne A Pyzytulinska M Tao ZF Stewart KD Kovar P Chen Z Credo RB Guan R Merta PJ Zhang H Bouska J Everitt EA Murry BP Hickman D Stratton TJ Wu J Rosenberg SH Sham HL Sowin TJ Lin NH 《Bioorganic & medicinal chemistry letters》2007,17(13):3618-3623
A study on substitutions at the four open positions on the phenyl ring of the 1,4-dihydroindeno[1,2-c]pyrazoles as potent CHK-1 inhibitors is described. Bis-substitution at both the 6- and 7-positions led to inhibitors with IC(50) values below 0.3nM. The compound with the best overall activities (36) was able to potentiate the anti-proliferative effect of doxorubicin in HeLa cells by at least 47-fold. Physicochemical, metabolic, and pharmacokinetic properties of selected inhibitors are also disclosed. 相似文献
102.
Marquez A Villa-Treviño S Guéraud F 《Redox report : communications in free radical research》2007,12(1):35-39
Growing evidence indicates oxidative stress as a mechanism of several diseases including cancer. Oxidative stress can be defined as the imbalance between cellular oxidant species production and antioxidant capability shifted towards the former. Lipid peroxidation is one of the processes that takes place during oxidative stress. Lipid peroxidation products, such as malondialdehyde (MDA) and 4-hydroxy-2-nonenal (HNE), are closely related to carcinogenesis as they are potent mutagens and they have been suggested as modulators of signal pathways related to proliferation and apoptosis, two processes implicated in cancer development. Mechanisms by which oxidative stress leads to tumor formation are still under investigation. The need of suitable in vivo models that could reflect that inflammation-related human carcinogenesis is evident. In this regard, the mutant strain Long Evans Cinnamon-like (LEC) rat provides a promising model for investigation of the relationship between hepatitis induced by oxidative stress and hepatocarcinogenesis because it has been demonstrated to develop spontaneous liver tumor formation related to copper accumulation and oxidative stress. In this review, the findings regarding oxidative stress and its relation with liver pathologies in LEC rats are discussed; we focus on the mechanisms proposed for HNE carcinogenesis. 相似文献
103.
104.
A better understanding of how ecological novelty influences interactions in new combinations of species is key for predicting interaction outcomes, and can help focus conservation and management efforts on preventing the introduction of novel organisms or species (including invasive species, GMOs, synthetic organisms, resurrected species and emerging pathogens) that seem particularly ‘risky’ for resident species. Here, we consider the implications of different degrees of eco‐evolutionary experience of interacting resident and non‐resident species, define four qualitative risk categories for estimating the probability of successful establishment and impact of novel species and discuss how the effects of novelty change over time. Focusing then on novel predator–prey interactions, we argue that novelty entails density‐dependent advantages for non‐resident species, with their largest effects often being at low prey densities. This is illustrated by a comparison of predator functional responses and prey predation risk curves between novel species and ecologically similar resident species, and raises important issues for the conservation of endangered resident prey species. 相似文献
105.
Sedman VL Kasotakis E Chen X Allen S Roberts CJ Mitraki A Tendler SJ 《Protein and peptide letters》2011,18(3):268-274
Here we present a study of five analogues of a fragment from the shaft domain of the adenovirus fibre protein that readily form fibrils under a range of conditions. Using atomic force microscopy the fibrillisation of these peptides at the liquid/solid interface utilizing ordered crystalline substrates has been investigated. Our results demonstrate that the assembly pathway at the liquid/solid interface enables only the formation of truncated fibrillar structures, which align along the substrate's underlying atomic lattice during growth. Furthermore, that the concentration and volume of solution applied can be used to directly control the density of fibrillar coverage at the surface. 相似文献
106.
Eisen L Coleman M Lozano-Fuentes S McEachen N Orlans M Coleman M 《PLoS neglected tropical diseases》2011,5(3):e1016
Background
Emerging information technologies present new opportunities to reduce the burden of malaria, dengue and other infectious diseases. For example, use of a data management system software package can help disease control programs to better manage and analyze their data, and thus enhances their ability to carry out continuous surveillance, monitor interventions and evaluate control program performance.Methods and Findings
We describe a novel multi-disease data management system platform (hereinafter referred to as the system) with current capacity for dengue and malaria that supports data entry, storage and query. It also allows for production of maps and both standardized and customized reports. The system is comprised exclusively of software components that can be distributed without the user incurring licensing costs. It was designed to maximize the ability of the user to adapt the system to local conditions without involvement of software developers. Key points of system adaptability include 1) customizable functionality content by disease, 2) configurable roles and permissions, 3) customizable user interfaces and display labels and 4) configurable information trees including a geographical entity tree and a term tree. The system includes significant portions of functionality that is entirely or in large part re-used across diseases, which provides an economy of scope as new diseases downstream are added to the system at decreased cost.Conclusions
We have developed a system with great potential for aiding disease control programs in their task to reduce the burden of dengue and malaria, including the implementation of integrated vector management programs. Next steps include evaluations of operational implementations of the current system with capacity for dengue and malaria, and the inclusion in the system platform of other important vector-borne diseases. 相似文献107.
Moro PL Budke CM Schantz PM Vasquez J Santivañez SJ Villavicencio J 《PLoS neglected tropical diseases》2011,5(5):e1179
Background
Cystic echinococcosis (CE) constitutes an important public health problem in Peru. However, no studies have attempted to estimate the monetary and non-monetary impact of CE in Peruvian society.Methods
We used official and published sources of epidemiological and economic information to estimate direct and indirect costs associated with livestock production losses and human disease in addition to surgical CE-associated disability adjusted life years (DALYs) lost.Findings
The total estimated cost of human CE in Peru was U.S.$2,420,348 (95% CI:1,118,384–4,812,722) per year. Total estimated livestock-associated costs due to CE ranged from U.S.$196,681 (95% CI:141,641–251,629) if only direct losses (i.e., cattle and sheep liver destruction) were taken into consideration to U.S.$3,846,754 (95% CI:2,676,181–4,911,383) if additional production losses (liver condemnation, decreased carcass weight, wool losses, decreased milk production) were accounted for. An estimated 1,139 (95% CI: 861–1,489) DALYs were also lost due to surgical cases of CE.Conclusions
This preliminary and conservative assessment of the socio-economic impact of CE on Peru, which is based largely on official sources of information, very likely underestimates the true extent of the problem. Nevertheless, these estimates illustrate the negative economic impact of CE in Peru. 相似文献108.
Background
Retinopathy of prematurity (ROP) is a major cause of vision impairment in low birth weight infants. While previous work has focused on defining the mechanisms of vascular injury leading to retinal neovascularization, recent studies show that neurons are also affected. This study was undertaken to determine the role of the mitochondrial arginine/ornithine regulating enzyme arginase 2 (A2) in retinal neuro-glial cell injury in the mouse model of ROP.Methods and Findings
Studies were performed using wild type (WT) and A2 knockout (A2−/−) mice exposed to Oxygen Induced Retinopathy (OIR). Neuronal injury and apoptosis were assessed using immunohistochemistry, TUNEL (terminal deoxynucleotidyl transferase dUTP nick end) labeling and Western blotting. Electroretinography (ERG) was used to assess retinal function. Neuro-glial injury in WT ROP mice was evident by TUNEL labeling, retinal thinning, decreases in number of rod bipolar cells and glial cell activation as compared with room air controls. Significant reduction in numbers of TUNEL positive cells, inhibition of retinal thinning, preservation of the rod bipolar cells and prevention of glial activation were observed in the A2−/− retinas. Retinal function was markedly impaired in the WT OIR mice as shown by decreases in amplitude of the b-wave of the ERG. This defect was significantly reduced in A2−/− mice. Levels of the pro-apoptotic proteins p53, cleaved caspase 9, cytochrome C and the mitochondrial protein Bim were markedly increased in WT OIR retinas compared to controls, whereas the pro-survival mitrochondrial protein BCL-xl was reduced. These alterations were largely blocked in the A2−/− OIR retina.Conclusions
Our data implicate A2 in neurodegeneration during ROP. Deletion of A2 significantly improves neuronal survival and function, possibly through the regulation of mitochondrial membrane permeability mediated apoptosis during retinal ischemia. These molecular events are associated with decreased activation of glial cells, suggesting a rescue effect on macroglia as well. 相似文献109.
Mahir Saul 《American anthropologist》2003,105(2):466-467
The Same but Different: Language Use and Attitudes in Four Communities of Burkina Faso. Stuart Showalter. Dallas: SIL International, 2001. 261 pp. 相似文献
110.