211,643 research outputs found
Natriuretic peptide receptor-C is up-regulated in the intima of advanced carotid artery atherosclerosis
OBJECTIVE: Natriuretic peptide receptor-C (NPR-C/NPR-3) is a cell surface protein involved in vascular remodelling that is up-regulated in atherosclerosis. NPR-C expression has not been well characterized in human carotid artery occlusive lesions. We hypothesized that NPR-C expression correlates with intimal features of vulnerable atherosclerotic carotid artery plaque. METHODS: To test this hypothesis, we evaluated NPR-C expression by immunohistochemistry (IHC) in carotid endarterectomy (CEA) specimens isolated from 18 patients. The grade, location, and co-localization of NPR-C in CEA specimens were evaluated using two tissue analysis techniques. RESULTS: Relative to minimally diseased CEA specimens, we observed avid NPR-C tissue staining in the intima of maximally diseased CEA specimens (65%; p=0.06). Specifically, maximally diseased CEA specimens demonstrated increased NPR-C expression in the superficial intima (61%, p=0.17), and deep intima (138% increase; p=0.05). In the superficial intima, NPR-C expression significantly co-localized with vascular smooth muscle cells (VSMCs) and macrophages. The intensity of NPR-C expression was also higher in the superficial intima plaque shoulder and cap regions, and significantly correlated with atheroma and fibroatheroma vulnerable plaque regions (β=1.04, 95% CI=0.46, 1.64). CONCLUSION: These findings demonstrate significant NPR-C expression in the intima of advanced carotid artery plaques. Furthermore, NPR-C expression was higher in vulnerable carotid plaque intimal regions, and correlate with features of advanced disease. Our findings suggest that NPR-C may serve as a potential biomarker for carotid plaque vulnerability and progression, in patients with advanced carotid artery occlusive disease
Effect of aging on endogenous level of 5 alpha-dihydrotestosterone, testosterone, estradiol, and estrone in epithelium and stroma of normal and hyperplastic human prostate.
associated with aging. Thus, the question arises whether or not a
correlation exists between the well known prostatic androgen and
estrogen accumulation and aging. To address this question, we measured
5a-dihydrotestosterone (DHT), testosterone, estradiol, and estrone
in epithelium and stroma of six normal (NPR) and 19 BPH and
correlated the values with the age of the donors (26-87 yr). The mean
DHT level in NPR epithelium was significantly higher than in NPR
stroma, and also significantly higher than in epithelium and stroma of
BPH. The epithelial DHT level of NPR and BPH decreased with age,
the correlation being statistically significant. The stromal DHT level
of NPR and BPH showed no correlation with age. Concerning testosterone,
generally rather low values were found which showed no correlation
with age. The mean levels of estradiol and estrone were
significantly higher in BPH stroma as compared to BPH epithelium
as well as to NPR epithelium and stroma. In NPR, the mean levels of
estradiol and estrone were significantly higher in epithelium than
stroma. In NPR and BPH, the stromal estradiol and estrone levels
increased significantly with age. In epithelium such a correlation between
the estrogen levels and age was not found. Our results indicate
that the prostatic accumulation of DHT, estradiol, and estrone is in
part intimately correlated with aging, leading with increasing age to a
dramatic increase of the estrogen/androgen ratio particularly in stroma
of BPH
An opioid-like system regulating feeding behavior in C. elegans
Neuropeptides are essential for the regulation of appetite. Here we show that neuropeptides could regulate feeding in mutants that lack neurotransmission from the motor neurons that stimulate feeding muscles. We identified nlp-24 by an RNAi screen of 115 neuropeptide genes, testing whether they affected growth. NLP-24 peptides have a conserved YGGXX sequence, similar to mammalian opioid neuropeptides. In addition, morphine and naloxone respectively stimulated and inhibited feeding in starved worms, but not in worms lacking NPR-17, which encodes a protein with sequence similarity to opioid receptors. Opioid agonists activated heterologously expressed NPR-17, as did at least one NLP-24 peptide. Worms lacking the ASI neurons, which express npr-17, did not response to naloxone. Thus, we suggest that Caenorhabditis elegans has an endogenous opioid system that acts through NPR-17, and that opioids regulate feeding via ASI neurons. Together, these results suggestC. elegans may be the first genetically tractable invertebrate opioid model
Managing purchasing of non-product related (NPR) goods and services - On horizontal frictions and vertical ignorance
This paper investigates the current practice with regard to the involvement of the purchasing department(s) in NPR purchasing. First we review the literature about NPR purchasing, and especially the major benefits and challenges of involving purchasing department in NPR purchasing. Furthermore the paper explores some theoretical explanations of why certain tasks regarding NPR purchasing should be attributed to a purchasing specialist and others should not. In order to refine the theoretical explanations we als conducted an empirical study. The findings of the emipirical research are presented at the end of the paper. The main conclusion is that top management - at least in theory - could improve its grip on NPRpurchasing by more clearly creating the conditions for a self-regulating "economic system" within the firm which offers internal departments different possibilities for organizing their respective purchasing activities. These conditions must allow for letting the internal customer be in charge of purchasing themselves, but also offer the possibility of buying purchasing assistance on a "market" and/or developing co-operative relationships with a purchasing specialist
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