In this task, you are given a passage which has a question and the context. You have to generate an answer to the question based on the information present in the context.

Context: Platelets are a natural source of growth factors, cytokines and chemokines, that regulate angiogenesis and inflammation. It has been suggested that differential release of pro- and anti-angiogenic growth factors from platelet -granules by protease-activated receptors (PAR) 1 and 4 may be important for the regulation of angiogenesis. We aimed to compare the releasates of unstimulated platelets with PAR-1- and PAR-4-stimulated platelets.', "The release of -thromboglobulin, platelet factor (PF)-4, thrombospondin, platelet-derived growth factor (PDGF)-A/B, regulated and normal T-cell expressed and secreted (RANTES/CCL5), endostatin, CXCL12, and vascular endothelial growth factor (VEGF) was measured with enzyme-linked immunosorbent assay (ELISA). Mass spectrometry (MS)-based quantitative proteomics identified 93 proteins from platelets stimulated with PAR-1 and PAR-4. A strong correlation between the factors released after either stimulus was observed (Spearman's r 0.94, P < 0.001). Analysis with ELISA showed that stimulation with PAR-1 or PAR-4 lead to non-differential release of -thromboglobulin, PF-4, thrombospondin, PDGF-A/B, RANTES/CCL5, endostatin, CXCL12, and VEGF. Release of thrombospondin was slightly lower after PAR-1 stimulation (7.2 g/mL), compared with PAR-4 induced release (9.8 g/mL; P < 0.05).\Question: Does quantitative proteomics analysis reveal similar release profiles following specific PAR-1 or PAR-4 stimulation of platelets?
Both ELISA on established -granule proteins and MS-based quantitative proteomics showed that the most abundant -granule proteins are released in similar quantities from platelets after stimulation with either PAR-1 or PAR-4. Our findings provide evidence against the hypothesis that PAR-1 and PAR-4 stimulation of platelets trigger differential release of alpha-granule, but further studies are needed to draw conclusions for physiological conditions.

Context: Intrathecal adenosine is antinociceptive under conditions of central sensitization, but not in response to acute stimuli in normals. The reasons for this selective circumstance of action remain unclear, but some evidence links adenosine's antinociceptive effects to release of norepinephrine by terminals in the spinal cord. The purpose of this study was to test whether spinal adenosine induces norepinephrine release selectively in settings of hypersensitivity.", 'Rats randomly assigned to spinal nerve ligation, sham operation, or no operation were anesthetized. A microdialysis fiber was implanted in the spinal cord dorsal horn at the L5-L6 level and perfused with artificial cerebrospinal fluid. After washout and a baseline sample period, adenosine at various concentrations was infused through the fiber for 150 min, and samples were collected every 15 min.', "In ligated, but not in sham or normal animals, adenosine perfusion increased norepinephrine in spinal cord microdialysates in a concentration-dependent manner. The effects of adenosine plateaued after 75 min and remained stable until the end of the experiment. Intravenous injection of selective adenosine A1 and A2 receptor antagonists revealed that adenosine's effect on spinal norepinephrine release was A1 receptor mediated.\Question: Does intraspinal adenosine induce spinal cord norepinephrine release in spinal nerve-ligated rats but not in normal or sham controls?
This is the first study to provide direct evidence that adenosine is able to release norepinephrine in spinal cord dorsal horns in living animals. However, this effect was only seen in animals after spinal nerve ligation. These data are consistent with behavioral studies demonstrating that adenosine's antinociceptive effects in rats after spinal nerve ligation is totally dependent on intact spinal noradrenergic terminals and can be blocked by spinal alpha 2-adrenergic receptor antagonists.

Context: The aim of this study was to investigate the value of p53 and cyclin D1 gene expression in predicting the risk of occult lymph node metastases in patients with head and neck squamous cell carcinoma (HNSCC).', 'The expression of cyclin D1 and p53 was evaluated by means of immunohistochemical analysis in 32 HNSCC patients with clinically and radiologically negative lymph nodes in whom metastatic involvement was subsequently demonstrated at histologic examination (pN+). A group of 64 head and neck cancer patients with histologically negative laterocervical lymph nodes (pN0) was used as a control.', 'Cyclin D1 and p53 expression were observed respectively in 42 (43.7%) and 48 cases (50%). Cyclin D1 expression significantly correlated with tumor extension and advanced clinical stage (p =.002 and p =.001, respectively). At univariate regression analysis, cyclin D1 expression significantly correlated with the presence of occult lymph node metastases (p =. 0007), and it remained an independent predictor at multivariate regression analysis (p =.0059).\Question: Is cyclin D1 expression predictive of occult metastases in head and neck cancer patients with clinically negative cervical lymph nodes?
Our study indicates that the expression of cyclin D1 correlates with the presence of occult cervical metastases in head and neck carcinoma patients, thus suggesting that its immunohistochemical evaluation in biopsy samples may be used as an additional tool for identifying patients to be treated with elective neck dissection.