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The vanilloid receptor transient receptor potential type V1 (TRPV1) integrates responses to multiple stimuli, such as capsaicin, acid, heat, and endovanilloids and plays an important role in the transmission of inflammatory pain. Here, we report the identification and in vitro characterization of A-425619 [1-isoquinolin-5-yl-3-(4-trifluoromethyl-benzyl)-urea], a novel, potent, and selective TRPV1 antagonist. A-425619 was found to potently block capsaicin-evoked increases in intracellular calcium concentrations in HEK293 cells expressing recombinant human TRPV1 receptors (IC50 = 5 nM). A-425619 showed similar potency (IC50 = 3-4 nM) to block TRPV1 receptor activation by anandamide and N-arachidonoyl-dopamine. Electrophysiological experiments showed that A-425619 also potently blocked the activation of native TRPV1 channels in rat dorsal root ganglion neurons (IC50 = 9 nM). When compared with other known TRPV1 antagonists, A-425619 exhibited superior potency in blocking both naive and phorbol ester-sensitized TRPV1 receptors. Like capsazepine, A-425619 demonstrated competitive antagonism (pA2 = 2.5 nM) of capsaicin-evoked calcium flux. Moreover, A-425619 was 25- to 50-fold more potent than capsazepine in blocking TRPV1 activation. A-425619 showed no significant interaction with a wide range of receptors, enzymes, and ion channels, indicating a high degree of selectivity for TRPV1 receptors. These data show that A-425619 is a structurally novel, potent, and selective TRPV1 antagonist.  相似文献   
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The transient receptor potential vanilloid (TRPV) 1 receptor, a nonselective cation channel expressed on peripheral sensory neurons and in the central nervous system, plays a key role in pain. TRPV1 receptor antagonism is a promising approach for pain management. In this report, we describe the pharmacological and functional characteristics of a structurally novel TRPV1 antagonist, (R)-(5-tert-butyl-2,3-dihydro-1H-inden-1-yl)-3-(1H-indazol-4-yl)-urea (ABT-102), which has entered clinical trials. At the recombinant human TRPV1 receptor ABT-102 potently (IC(50) = 5-7 nM) inhibits agonist (capsaicin, N-arachidonyl dopamine, anandamide, and proton)-evoked increases in intracellular Ca(2+) levels. ABT-102 also potently (IC(50) = 1-16 nM) inhibits capsaicin-evoked currents in rat dorsal root ganglion (DRG) neurons and currents evoked through activation of recombinant rat TRPV1 currents by capsaicin, protons, or heat. ABT-102 is a competitive antagonist (pA(2) = 8.344) of capsaicin-evoked increased intracellular Ca(2+) and shows high selectivity for blocking TRPV1 receptors over other TRP receptors and a range of other receptors, ion channels, and transporters. In functional studies, ABT-102 blocks capsaicin-evoked calcitonin gene-related peptide release from rat DRG neurons. Intraplantar administration of ABT-102 blocks heat-evoked firing of wide dynamic range and nociceptive-specific neurons in the spinal cord dorsal horn of the rat. This effect is enhanced in a rat model of inflammatory pain induced by administration of complete Freund's adjuvant. Therefore, ABT-102 potently blocks multiple modes of TRPV1 receptor activation and effectively attenuates downstream consequences of receptor activity. ABT-102 is a novel and selective TRPV1 antagonist with pharmacological and functional properties that support its advancement into clinical studies.  相似文献   
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The pathogenesis of cerebral ischaemia reperfusion injury (IRI) has not been fully described. Accordingly, there is little effective drug available for the treatment of cerebral IRI. The aim of our study was to explore the exact role played by Mfn1‐mediated mitochondrial protection in cerebral IRI and evaluate the beneficial action of resveratrol on reperfused brain. Our study demonstrated that hypoxia‐reoxygenation (HR) injury caused N2a cell apoptosis and this process was highly affected by mitochondrial dysfunction. Decreased mitochondrial membrane potential, increased mitochondrial oxidative stress, and an activated mitochondrial apoptosis pathway were noted in HR‐treated N2a cells. Interestingly, resveratrol treatment could attenuate N2a cell apoptosis via sustaining mitochondrial homeostasis. Further, we found that resveratrol modulated mitochondrial performance via activating the Mfn1‐related mitochondrial protective system. Knockdown of Mfn1 could abolish the beneficial effects of resveratrol on HR‐treated N2a cells. Besides, we also report that resveratrol regulated Mfn1 expression via the AMPK pathway; inhibition of AMPK pathway also neutralized the anti‐apoptotic effect of resveratrol on N2a cells in the setting of cerebral IRI. Taken together our results show that mitochondrial damage is closely associated with the progression of cerebral IRI. In addition we also demonstrate the protective action played by resveratrol on reperfused brain and show that this effect is achieved via activating the AMPK‐Mfn1 pathway.  相似文献   
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Wrist fractures are common in postmenopausal women and are associated with functional decline. Fracture patterns after wrist fracture are unclear. The goal of this study was to determine the frequency and types of fractures that occur after a wrist fracture among postmenopausal women. We carried out a post hoc analysis of data from the Women's Health Initiative Observational Study and Clinical Trials (1993–2010) carried out at 40 US clinical centers. Participants were postmenopausal women aged 50 to 79 years at baseline. Mean follow‐up duration was 11.8 years. Main measures included incident wrist, clinical spine, humerus, upper extremity, lower extremity, hip, and total non‐wrist fractures and bone mineral density (BMD) in a subset. Among women who experienced wrist fracture, 15.5% subsequently experienced non‐wrist fracture. The hazard for non‐wrist fractures was higher among women who had experienced previous wrist fracture than among women who had not experienced wrist fracture: non‐wrist fracture overall (hazard ratio [HR] = 1.40, 95% confidence interval [CI] 1.33–1.48), spine (HR = 1.48, 95% CI 1.32–1.66), humerus (HR = 1.78, 95% CI 1.57–2.02), upper extremity (non‐wrist) (HR = 1.88, 95% CI 1.70–2.07), lower extremity (non‐hip) (HR = 1.36, 95% CI 1.26–1.48), and hip (HR = 1.50, 95% CI 1.32–1.71) fracture. Associations persisted after adjustment for BMD, physical activity, and other risk factors. Risk of non‐wrist fracture was higher in women who were younger when they experienced wrist fracture (interaction p value 0.02). Associations between incident wrist fracture and subsequent non‐wrist fracture did not vary by baseline BMD category (normal, low bone density, osteoporosis). A wrist fracture is associated with increased risk of subsequent hip, vertebral, upper extremity, and lower extremity fractures. There may be substantial missed opportunity for intervention in the large number of women who present with wrist fractures. © 2015 American Society for Bone and Mineral Research.  相似文献   
38.
The photosensitivity in cis-polyphenylacetylene (cis-PPA, polymerized with rare-earth catalysts) can be significantly enhanced by doping the PPA with I2 or FeCl3 and sensitizing with 4-isothiocyanatofluorescein (F-II) or 2,4,7-trinitro-9-fluorenone (TNF), which are powerful sensitizers. The electrophotographic photoreceptor (P/R) device with cis-PPA + F-II (on Al substrate) appeared preferable in photosensitivity enhancement and showed good photosensitivity: dark decay 1,8 V/s; maximum rate of discharge 321 V/s; residual surface potential 22 V; discharge 89, 1%; photosensitivity 2,96 s?1. This is a new “family” of photosensitive materials which can be used in a duplicator.  相似文献   
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This policy paper addresses the problem of underrepresentation of minorities in the health care professions. Projections are that by 2050 minorities will represent 49% of the U.S. population. Several notable reports suggest that the health care of underrepresented minorities is improved when providers of similar ethnic and racial backgrounds provide the care. However, minority representation in the health care professions has not kept pace with the increase of minorities in the population. A variety of groups (federal, state, private, and health professional educational institutions) have provided billions of dollars toward increasing the number of underrepresented minority health care providers. However, the effectiveness of these programs is not readily evident. Therefore, we recommend comprehensive evaluations of programs funded to increase diversity in the health professions and the development of a Minority Health Care Professionals Center to assume accountability for monitoring programs that receive funding to increase the number of underrepresented minority health care providers.  相似文献   
40.

1 Background

Hypertension and periodontal disease are common conditions among postmenopausal women. Periodontal disease has been found associated with hypertension in previous studies, but data in postmenopausal women is limited.

2 Methods

We assessed the cross‐sectional associations of clinically measured periodontal disease with prevalent hypertension and measured systolic blood pressure (SBP) among 1341 postmenopausal women enrolled in the Buffalo Osteoporosis and Periodontal Disease (OsteoPerio) study, an ancillary study of the Women's Health Initiative‐Observational Study.

3 Results

Clinical attachment level (CAL) and number of teeth missing were positively associated with SBP among those not taking antihypertensive medication in crude and multivariable adjusted linear regression models (both < 0.05). Alveolar crestal height (ACH) and gingival bleeding on probing were associated with higher SBP in crude but not multivariable adjusted models. Neither probing pocket depth (PPD) nor severity categories of periodontitis were associated with SBP. Number of teeth missing was significantly associated with prevalent hypertension in crude and multivariable adjusted models (OR = 1.14, per 5 teeth; = 0.04). ACH was associated with prevalent hypertension in crude but not adjusted models. CAL, PPD, gingival bleeding, and severity of periodontitis were not significantly associated with prevalent hypertension.

4 Conclusions

These results suggest that measures of oral health including CAL and number of teeth missing are associated with blood pressure in postmenopausal women. Prospective studies are needed to further investigate these associations and the potential underlying mechanisms for these relationships.  相似文献   
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