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61.
Andrew Leask 《Journal of cell communication and signaling》2010,4(1):73-74
Connective tissue growth factor (CTGF/CCN2) is overexpressed in diabetes. Diabetic rats possess myocardial and cardiomyocyte hypertrophy. In a recent report, Wang and colleagues (Am J Physiol Cell Physiol. 2009 Jul 22. [Epub ahead of print]) show that CCN2 directly mediates cardiomyocyte hypertrophy as well as that induced by high glucose and fatty acid. CCN2 acted via the TrkA receptor. These data are the subject of this commentary, and emphasize that CCN2 may be an excellent target for therapy in diabetes. 相似文献
62.
《Fungal biology》2020,124(2):83-90
Latterly, the upsurge in use of antifungal drugs has brought about the emergence of several drug-resistance strains, making it skeptical to continue relying on current therapeutic regime. In the necessity of resistance-free antifungal agent, flavonoids presented possibilities of replacing existing drugs, displaying antifungal activity against pathogenic fungi. Among them, quercetin, one of the most representative flavonoids, exhibited antifungal activity against Candida albicans. To inspect the further understanding regarding quercetin, the antifungal mode of action of quercetin was investigated. In the initial step, the apoptosis was monitored after quercetin treatment. Moreover, intracellular levels of Mg2+ was assessed and was determined that Mg2+ increase occurred under the influence of quercetin. In addition, several features of mitochondrial dysfunction were monitored. Mitochondrial dysfunction triggers decrease in mitochondrial redox levels and leads to disruption in mitochondrial antioxidant system. Increased intracellular ROS and decreased intracellular redox levels were also displayed, indicating the occurrence of overall disruption in antioxidant systems. Sequentially, DNA fragmentation was observed and this DNA damage in turn induces apoptosis. In analyses, hexaamminecobalt(III) chloride (Cohex) was applied to inhibit Mg2+ transport between cytosol and mitochondria. Cohex attenuated the effects induced by quercetin, which demonstrates that the presence of Mg2+ is essential in quercetin-induced apoptosis. 相似文献
63.
Steven M. Melemis 《The Yale journal of biology and medicine》2015,88(3):325-332
There are four main ideas in relapse prevention. First, relapse is a gradual process with distinct stages. The goal of treatment is to help individuals recognize the early stages, in which the chances of success are greatest. Second, recovery is a process of personal growth with developmental milestones. Each stage of recovery has its own risks of relapse. Third, the main tools of relapse prevention are cognitive therapy and mind-body relaxation, which are used to develop healthy coping skills. Fourth, most relapses can be explained in terms of a few basic rules. Educating clients in these rules can help them focus on what is important: 1) change your life (recovery involves creating a new life where it is easier to not use); 2) be completely honest; 3) ask for help; 4) practice self-care; and 5) don’t bend the rules. 相似文献
64.
Abstract. Growth rates throughout an organ curving phototropically under continuous, unilateral while light were monitored by lime-lapse photography of cress hypocotyls marked into 1 mm sections by two rows of ion-exchange beads. Curvature resulted from an integrated sequence of changes in growth rate on each side of the organ, but the actual patterns of change and, therefore rales of curvature, differed within even this one species, depending upon the immediate pretreatment of the seedlings. Transference of seedlings from darkness to unilateral irradiation gave immediate growth inhibition on both sides of the organ. Curvature resulted from differential recovery of growth rate, being seen first on the shaded side, most prominently in the apical regions; only 2h after initial exposure to light did growth recover on the lit (lower) side. On the other hand, transfer of seedlings from omnilateral to unilateral irradiation of the same intensity resulted in simultaneous growth inhibition on the irradiated side and stimulated growth on the shaded side: this growth stimulation of the shaded side was greater than occurred in totally darkened control plants. 相似文献
65.
David Dávila Silvia Fernández Ignacio Torres-Alemán 《The Journal of biological chemistry》2016,291(5):2510-2523
Disruption of insulin-like growth factor I (IGF-I) signaling is a key step in the development of cancer or neurodegeneration. For example, interference of the prosurvival IGF-I/AKT/FOXO3 pathway by redox activation of the stress kinases p38 and JNK is instrumental in neuronal death by oxidative stress. However, in astrocytes, IGF-I retains its protective action against oxidative stress. The molecular mechanisms underlying this cell-specific protection remain obscure but may be relevant to unveil new ways to combat IGF-I/insulin resistance. Here, we describe that, in astrocytes exposed to oxidative stress by hydrogen peroxide (H2O2), p38 activation did not inhibit AKT (protein kinase B) activation by IGF-I, which is in contrast to our previous observations in neurons. Rather, stimulation of AKT by IGF-I was significantly higher and more sustained in astrocytes than in neurons either under normal or oxidative conditions. This may be explained by phosphorylation of the phosphatase PTEN at the plasma membrane in response to IGF-I, inducing its cytosolic translocation and preserving in this way AKT activity. Stimulation of AKT by IGF-I, mimicked also by a constitutively active AKT mutant, reduced oxidative stress levels and cell death in H2O2-exposed astrocytes, boosting their neuroprotective action in co-cultured neurons. These results indicate that armoring of AKT activation by IGF-I is crucial to preserve its cytoprotective effect in astrocytes and may form part of the brain defense mechanism against oxidative stress injury. 相似文献
66.
Sensitivity to and requirement for iron in Plantago species 总被引:1,自引:0,他引:1
67.
Bone Cell-autonomous Contribution of Type 2 Cannabinoid Receptor to Breast Cancer-induced Osteolysis
Antonia Sophocleous Silvia Marino John G. Logan Patrick Mollat Stuart H. Ralston Aymen I. Idris 《The Journal of biological chemistry》2015,290(36):22049-22060
The cannabinoid type 2 receptor (CB2) has previously been implicated as a regulator of tumor growth, bone remodeling, and bone pain. However, very little is known about the role of the skeletal CB2 receptor in the regulation of osteoblasts and osteoclasts changes associated with breast cancer. Here we found that the CB2-selective agonists HU308 and JWH133 reduced the viability of a variety of parental and bone-tropic human and mouse breast cancer cells at high micromolar concentrations. Under conditions in which these ligands are used at the nanomolar range, HU308 and JWH133 enhanced human and mouse breast cancer cell-induced osteoclastogenesis and exacerbated osteolysis, and these effects were attenuated in cultures obtained from CB2-deficient mice or in the presence of a CB2 receptor blocker. HU308 and JWH133 had no effects on osteoblast growth or differentiation in the presence of conditioned medium from breast cancer cells, but under these circumstances both agents enhanced parathyroid hormone-induced osteoblast differentiation and the ability to support osteoclast formation. Mechanistic studies in osteoclast precursors and osteoblasts showed that JWH133 and HU308 induced PI3K/AKT activity in a CB2-dependent manner, and these effects were enhanced in the presence of osteolytic and osteoblastic factors such as RANKL (receptor activator of NFκB ligand) and parathyroid hormone. When combined with published work, these findings suggest that breast cancer and bone cells exhibit differential responses to treatment with CB2 ligands depending upon cell type and concentration used. We, therefore, conclude that both CB2-selective activation and antagonism have potential efficacy in cancer-associated bone disease, but further studies are warranted and ongoing. 相似文献
68.
Takahiro Ishii Tatsufumi Okino Yosuke Mino Hiroaki Tamiya Fuyuhiko Matsuda 《Plant Growth Regulation》2007,52(2):131-139
Starfish waste has been shown to be an effective compost material not only in the promotion of plant growth but also in terms
of having insecticidal activity. In the present study, plant growth regulation by chemicals from starfish was examined. The
aqueous fraction from a hot water extract of the starfish Asterias amurensis Lütken showed plant-growth activity, while the aqueous fraction from a methanol extract inhibited growth of Brassica campestris. The lipophilic fraction from the methanol extract also exhibited a plant growth-promoting effect. The active components
from each extract were identified. Asterubine from the hot water extract promoted plant growth. A ceramide from the lipophilic
fraction showed root growth promoting effect, and three glucocerebrosides had promotive effects on the entire plant. Asterosaponins
were identified as the main growth inhibitors in the aqueous fraction of the methanol extract. These active compounds from
starfish waste could be analyzed as potential plant growth regulators in agricultural applications in the future. 相似文献
69.
70.
Growth of 2659 Atlantic cod Gadus morhua aged 4 to 9 years examined in Placentia Bay, Newfoundland, peaked in most cases in June and was at a minimum in October or November. Water temperature, partial fullness index ( I P ) and gonado‐somatic index ( I G ) explained between 31 and 52% of the monthly variability in growth. Temperature and I P of capelin Mallotus villosus had significant effects on growth of all age groups and explained most of the variance for ages 6–8 and 4–5 years, respectively. The I P of large invertebrates (ages 4 to 7 years), sandlance ( Ammodytes sp. age 6 years) and demersal fishes (age 9 years) had age‐specific effects in the model. Overall, amphipods, decapods and echinoderms dominated the Atlantic cod diet in most seasons, but fish consumption by Atlantic cod was high in June and July, particularly on capelin. The rapid increase in somatic mass during June and July occurred despite cold water temperatures ( < 3° C at 50 m) and moderate to high gonado‐somatic index. The findings of this study suggest that when food was not a limiting factor, growth tended to increase even when Atlantic cod occupied colder waters, but when food was limiting, the opposite may have occured. 相似文献