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51.
Therapeutic interventions with Rho kinase (ROCK) inhibitors may effectively treat several disorders such as hypertension, stroke, cancer, and glaucoma. Herein we disclose the optimization and biological evaluation of potent novel ROCK inhibitors based on substituted indole and 7-azaindole core scaffolds. Substitutions on the indole C3 position and on the indole NH and/or amide NH positions all yielded potent and selective ROCK inhibitors (25, 42, and 50). Improvement of aqueous solubility and tailoring of in vitro and in vivo DMPK properties could be achieved through these substitutions.  相似文献   
52.
Rho kinase (ROCK) is an attractive therapeutic target for various diseases including glaucoma, hypertension, and spinal cord injury. Herein, we report the development of a series of ROCK-II inhibitors based on 4-quinazolinone and quinazoline scaffolds. SAR studies at three positions of the quinazoline core led to the identification of analogs with high potency against ROCK-II and good selectivity over protein kinase A (PKA).  相似文献   
53.
Rho kinase (ROCK) inhibitors are potential therapeutic agents to treat disorders such as hypertension, multiple sclerosis, cancers, and glaucoma. Here, we disclose the synthesis, optimization, biological evaluation of potent indole and 7-azaindole based ROCK inhibitors that have high potency on ROCK (IC(50)=1 nM) with 740-fold selectivity over PKA (47). Moreover, 47 showed very good DMPK properties making it a good candidate for further development. Finally, docking studies with a homology model of ROCK-II were performed to rationalize the binding mode of these compounds and showed the compounds bound in both orientations to take advantage to H-bonds with Lys-121 of ROCK-II.  相似文献   
54.
Adherens junctions, which play a central role in intercellular adhesion, comprise clusters of type I classical cadherins that bind via extracellular domains extended from opposing cell surfaces. We show that a molecular layer seen in crystal structures of E- and N-cadherin ectodomains reported here and in a previous C-cadherin structure corresponds to the extracellular architecture of adherens junctions. In all three ectodomain crystals, cadherins dimerize through a trans adhesive interface and are connected by a second, cis, interface. Assemblies formed by E-cadherin ectodomains coated on liposomes also appear to adopt this structure. Fluorescent imaging of junctions formed from wild-type and mutant E-cadherins in cultured cells confirm conclusions derived from structural evidence. Mutations that interfere with the trans interface ablate adhesion, whereas cis interface mutations disrupt stable junction formation. Our observations are consistent with a model for junction assembly involving strong trans and weak cis interactions localized in the ectodomain.  相似文献   
55.
Adelphocorisella australis sp. n. is described from north Queensland. This, the first representative of the genus known from Australia, is compared with the two previously described species, both from Japan.  相似文献   
56.
Although studies have reported the effects of the menstrual cycle on melatonin rhythmicity, none has investigated the effects of menopause on the melatonin rhythm. The circadian rhythm in melatonin and its relationship to subjective alertness was investigated in pre- and postmenopausal women under constant routine conditions (controlled posture, dim lighting, calorie intake, temperature, and prolonged wakefulness). Eleven healthy pre-menopausal (42+/-4 yr) and 10 postmenopausal women (55+/-2 yr) participated in the study. Salivary melatonin samples and subjective measures of alertness and sleepiness were assessed hourly during the 22 h constant routine protocol. Postmenopausal women had a significantly earlier melatonin acrophase (1.1+/-0.5 h clock time in decimal h; mean+/-SEM, p<0.05) compared to the pre-menopausal women (2.3+/-0.3 h). There was no significant difference between melatonin onset and amplitude between the pre-menopausal and postmenopausal women. Self-rated alertness declined in both study groups as the length of sleep deprivation increased. Melatonin onset preceded the onset of self-rated sleepiness in both groups. The time interval between melatonin onset and the onset of sleepiness and alertness offset was significantly greater in the postmenopausal women compared to the pre-menopausal women. In conclusion, under controlled experimental conditions the timing of the melatonin rhythm was advanced in postmenopausal women altering its phase relationship to subjective alertness and sleepiness.  相似文献   
57.
The endoplasmic reticulum (ER) is an extremely plastic and dynamic organelle. Its size and shape can undergo drastic changes to meet changing demands for ER-related functions, or as a response to drugs or pathogens. Because of the ER's key functions in protein and lipid synthesis, this organelle is a hotbed of detailed molecular analysis.  相似文献   
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Neutrophil oxidants are hypothesized to damage the gastric mucosa and promote carcinogenesis in people infected with Helicobacter pylori. To investigate this process we used wild-type and chronic granulomatous disease (CGD) mice with a targeted disruption of the gp91(phox) subunit of the NADPH oxidase. The mice were inoculated with a mouse-adapted strain of H. pylori and changes in gastric pathology were examined 12 and 30 weeks after infection. Glandular atrophy, a precursor lesion in the development of intestinal-type gastric carcinoma, and epithelial cell proliferation were both dramatically increased in the gastric body of CGD animals within 12 weeks. This correlated strongly with increased numbers of neutrophils in the mucosa (Pearson coefficient 0.97, P < 0.001). H. pylori is a noninvasive bacterium, and there was no increase in bacterial numbers in the CGD animals. Closer examination of the gastric tissue indicated the presence of degenerate neutrophils associated with atrophy. We hypothesize that the release of granule constituents from these neutrophils contributes to tissue damage. This is exacerbated by the absence of a functional NADPH oxidase, and is consistent with this enzyme complex having an important role in dampening the inflammatory response.  相似文献   
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