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131.
Propolis obtained from honeybee hives has been used in Oriental folk medicine as an anti-inflammatory, anti-carcinogenic, or immunomodulatory agent. However, the molecular basis for anti-inflammatory properties of propolis has not yet been established. Since nitric oxide (NO) synthesized by inducible nitric oxide synthase (iNOS) has been known to be involved in inflammatory and autoimmune-mediated tissue destruction, modulation of NO synthesis or action represents a new approach to the treatment of inflammatory and autoimmune diseases. The present study, therefore, examined effects of ethanol extract of propolis (EEP) on iNOS expression and activity of iNOS enzyme itself. Treatment of RAW 264.7 cells with EEP significantly inhibited NO production and iNOS protein expression induced by lipopolysaccharide (LPS) plus interferon-gamma (IFN-γ). EEP also inhibited iNOS mRNA expression and nuclear factor-kappa B (NF-κB) binding activity in a concentration-dependent manner. Furthermore, transfection of RAW 264.7 cells with iNOS promoter linked to a chloramphenicol acetyltransferase (CAT) reporter gene, revealed that EEP inhibited the iNOS promoter activity induced by LPS plus IFN-γ through the NF-κB sites of the iNOS promoter. In addition, EEP directly interfered with the catalytic activity of murine recombinant iNOS enzyme. These results suggest that EEP may exert its anti-inflammatory effect by inhibiting the iNOS gene expression via action on the NF-κB sites in the iNOS promoter and by directly inhibiting the catalytic activity of iNOS.  相似文献   
132.
To elucidate possible mechanisms of anti-angiogenic activity by curcumin, we performed cDNA microarray and found that curcumin modulated cell cycle related gene expression. For further confirmation, DNA contents and expression levels of cyclins, cyclin-dependent kinases (CDKs), and CDK inhibitors (CDKIs) were examined by FACS analysis and Western blotting, respectively. Curcumin was found to induce G0/G1 and/or G2/M phase cell cycle arrest, up-regulate CDKIs, p21WAF1/CIP1, p27KIP1, and p53, and slightly down-regulate cyclin B1 and cdc2 in ECV304 cells. However, expression level of other cyclins and CDKs were not changed by curcumin. We, therefore, conclude that the up-regulation of CDKIs by curcumin plays a critical role in the regulation of cell cycle distribution in these cells, which may have a major role in anti-angiogenic activity of curcumin.  相似文献   
133.
The in vivo binding of dopamine (DA) radioligands to D2 receptors can be affected by competition with endogenous dopamine. In the present study, we used a brain slice preparation that provides more controlled conditions than in vivo preparations in order to examine the relationship between synaptic DA and the binding of [3H]raclopride to D2 receptors. We also estimated the synaptic DA concentration in rat striatal slices by determining the changes in [3H]raclopride binding. To correlate the changes in [3H]raclopride binding with the concentration of synaptic DA, the kinetic parameters were determined. [3H]Raclopride reached equilibrium binding conditions within two hours. The Ki value for DA in inhibiting [3H]raclopride binding was about 2.2 nM. The increase in synaptic DA evoked by electrical stimulation decreased the striatal binding of [3H]raclopride in a frequency-dependent manner. Increases in the DA concentration evoked by amphetamine (AMPH) or cocaine decreased [3H]raclopride binding by 74% or 20%, respectively, corresponding to increases in the synaptic DA concentrations of 1.6 nM or 0.6 nM, respectively. Pargyline also decreased [3H]raclopride binding by 36% corresponding at a concentration of 1.2 nM. In contrast, the depletion of synaptic DA by alpha-methyl-p-tyrosine (alpha-MpT) increased the specific binding of [3H]raclopride by 43% when the DA concentration was decreased to 0.7 nM. The changes in the DA concentration at the synapse were responsible for the changes in the striatal binding of [3H]raclopride. The values calculated in this study may therefore approximate the changes in the synaptic DA concentration in rat striatal slices following manipulation.  相似文献   
134.
135.
Serum cytokine profiles in patients with Plasmodium vivax malaria who presented with and without hyperpyrexia were compared by a retrospective review of the medical records of the consecutive patients seen at the military hospitals near the demilitarized zone in the Republic of Korea from April 2000 through October 2001. Of 162 male patients studied, 120 (86.4%) presented with hyperpyrexia (i.e., an axillary temperature > or = 40 degrees C). The mean +/- SEM ages of the patients with and without hyperpyrexia were 21.5 +/- 0.14 and 21.9 +/- 0.39 years, respectively (P = 0.33). The mean +/- SEM concentrations of serum interleukin (IL)-6 (379.7 +/- 44.1 pg/mL versus 105.4 +/- 26.8 pg/mL; P = 0.002), IL-10 (583.4 +/- 58.2 pg/mL versus 142.4 +/- 39.7 pg/mL; P = 0.0001), and interferon-gamma (312.6 +/- 33.9 pg/mL versus 112.9 +/- 27.1 pg/mL; P = 0.0001) were significantly higher in patients with hyperpyrexia compared with those without hyperpyrexia. The mean +/- SEM concentrations of serum tumor necrosis factor-alpha were 155.5 +/- 54.5 pg/mL and 109.9 +/- 29.3 pg/mL (P = 0.27) in patients who presented with and without hyperpyrexia, respectively. Further studies are needed to examine whether serum concentrations of these cytokines also parallel their concentrations at the tissue sites of their production and action.  相似文献   
136.
This study aimed to elucidate some novel pharmacological activities of Lonicera japonica (Caprifoliaceae), which is widely used in Oriental folk medicine. The ethanolic extract of L. japonica (LJ) dose dependently inhibited chick chorioallantoic membrane angiogenesis. The antinociceptive activity of LJ was assessed using the acetic acid-induced constriction model in mice. LJ showed anti-inflammatory activity in two in-vivo models: the vascular permeability and air pouch models. LJ suppressed the production of nitric oxide via down-regulation of inducible nitric oxide synthase in lipopolysaccharide-stimulated RAW264.7 macrophage cells. However, LJ was unable to suppress induction of cyclooxygenase-2 in the stimulated macrophage cells. LJ decreased the reactive oxygen species level in the stimulated macrophage cells. In brief, the flowers of L. japonica possess potent anti-angiogenic and antinociceptive activities, in addition to anti-inflammatory activity, which partly supports its therapeutic efficacy.  相似文献   
137.
Inflammation is an important pathophysiologic mechanism of injury induced by intracerebral hemorrhage (ICH). The ubiquitin-proteasome system (UPS) regulates the inflammatory responses via the up-regulation of several pro-inflammatory molecules. In this study, we determined that a potent proteasome inhibitor, bortezomib, exerted therapeutic effects in experimental model of ICH. Either bortezomib (0.05, 0.2, 0.5, 1mg/kg) or vehicle was intravenously administered 2h after ICH induction. The high doses of bortezomib caused high mortality rates. Bortezomib at 0.2 mg/kg reduced the early hematoma growth and alleviated hematoma volume and brain edema at 3 days after ICH, compared with the ICH-vehicle group. The numbers of myeloperoxidase(+) neutrophils, Ox42(+) microglia, and TUNEL(+) cells in the perihematomal regions were decreased by bortezomib. Bortezomib induced significant decrements of mRNA expression of TNF-alpha and IL-6. The production of iNOS and COX2 was also reduced significantly by bortezomib. We concluded that the early treatment with bortezomib induced a reduction in the early hematoma growth and mitigated the development of brain edema, coupled with a marked inhibitory effect on inflammation in ICH.  相似文献   
138.

Background

Gastric insufflation is common during face mask ventilation and results in unfavourable respiratory events in children. The purpose of this study was to evaluate the effect of a muscle relaxant on gastric insufflation and determine the optimal inspiratory pressure during face mask ventilation in children.

Methods

Children aged one month to five years were randomly assigned to neuromuscular blocker (NM) or non-neuromuscular blocker (non-NM) groups. After administering intravenous anesthetics, face mask ventilation commenced via pressure-controlled mechanical ventilator. Initial inspiratory pressure was 10 cmH2O and was increased by 2 cmH2O until gastric insufflation was detected via gastric ultrasonography or epigastric auscultation. The primary outcome was the difference in the inspiratory pressure that causes gastric insufflation between the two groups. Diagnostic methods that detect gastric insufflation first were also evaluated.

Results

There was no significant difference in the median [interquartile range] inspiratory pressure inducing gastric insufflation between the non-NM (n = 52) and NM groups (n = 60) (18 [16-18] cmH2O vs 18.0 [16-20] cmH2O; median difference, 0 cmH2O; 95% confidence interval [CI], 0 to 2; P = 0.57). The incidence of gastric insufflation increased with increasing inspiratory pressure. Gastric insufflation was detected first by ultrasonography in 44% and by epigastric auscultation in 19% of the non-NM group (difference in percentage, 25%; 95% CI, 6 to 42; P = 0.006) and by ultrasonography in 73% and by epigastric auscultation in 7% of the NM group (difference in percentage, 66%; 95% CI, 50 to 78; P < 0.001).

Conclusions

A neuromuscular blocking agent has minimal effect on the inspiratory pressure that causes gastric insufflation during face mask ventilation in children.

Trial Registration

www.clinicaltrials.gov (NCT02471521); registered 15 June 2015.
  相似文献   
139.
Kim EH  Na HK  Kim DH  Park SA  Kim HN  Song NY  Surh YJ 《Carcinogenesis》2008,29(4):688-695
Recent studies suggest that inflammation is causally linked to carcinogenesis. Cyclooxygenase-2 (COX-2), a rate-limiting enzyme in the biosynthesis of prostaglandins, is inappropriately expressed in various cancers and hence recognized as one of the hallmarks of chronic inflammation-associated malignancies. However, the mechanistic role of COX-2 as a link between inflammation and cancer remains undefined. Here, we report that 15-deoxy-Delta(12,14)-prostaglandin J(2) (15d-PGJ(2)), one of the final products of COX-mediated arachidonic acid metabolism, upregulates the expression of COX-2 in the human breast cancer MCF-7 cell line. 15d-PGJ(2)-induced COX-2 expression was mediated by activation of Akt and subsequently activator protein-1 (AP-1). Furthermore, 15d-PGJ(2) formed reactive oxygen species, which led to increased phosphorylation of Akt, DNA binding of AP-1 and expression of COX-2. In contrast to 15d-PGJ(2), 9,10-dihydro-15d-PGJ(2) did not elicit any of effects induced by 15d-PGJ(2) in this study, suggesting that an electrophilic carbon center present in 15d-PGJ(2) is critical for COX-2 expression as well activation of upstream signal transduction induced by this cyclopentenone prostaglandin. Taken together, these observations suggest that 15d-PGJ(2) produced by COX-2 overexpression may function as a positive regulator of COX-2 in human breast cancer MCF-7 cells.  相似文献   
140.

Aims

We aimed to evaluate the association between diabetic microangiopathy and subclinical atherosclerosis as a marker of cardiovascular disease (CVD) risk in patients with newly diagnosed type 2 diabetes.

Methods

A total of 142 newly diagnosed type 2 diabetics who were free from CVD underwent evaluation of diabetic microangiopathy. Subclinical atherosclerosis was assessed by measuring carotid intima-media thickness (IMT), and the 10-year absolute risk of CVD was estimated using the UK Prospective Diabetes Study (UKPDS) Risk Engine.

Results

Subclinical atherosclerosis was found in 27 subjects (19.0%). The rates of hypertension and diabetic retinopathy were significantly higher among patients with subclinical atherosclerosis. The UKPDS 10-year risk for CVD was significantly increased in subjects with subclinical atherosclerosis. Old age, hypertension and the presence of diabetic retinopathy showed a significant association to subclinical atherosclerosis after further adjustments for gender, body mass index, smoking status, HbA1c, HDL cholesterol, LDL cholesterol and the presence of diabetic nephropathy.

Conclusions

This study shows that diabetic retinopathy is an independent risk marker for subclinical atherosclerosis in patients with newly diagnosed type 2 diabetes. We suggest that a diagnosis of diabetic retinopathy may warrant a more careful cardiovascular assessment even in the early stages of diabetes.  相似文献   
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