MDP Salts: A New Bonding Strategy for Zirconia.

Durable resin-ceramic adhesion may influence the clinical success of ceramic restorations, which has been one of the challenging issues in dentistry. The present study assessed the bond strength and chemical interaction of 10-methacryloxydecyl dihydrogen phosphate (MDP), MDP+silane, and MDP-salt primers to alumina-blasted zirconia ceramic by tensile bond strength test, surface elemental composition with x-ray photoelectron spectroscopy analysis, contact angle measurement, surface morphology with scanning electron microscopy, and surface topography with 3-dimensional confocal laser scanning microscope analyses. MDP-salt showed the highest tensile bond strength before and after thermocycling when compared with MDP and MDP+silane (P < 0.05). The measured contact angle values differed significantly (P < 0.001) in the order of MDP-salt > control (no chemical pretreatment) > MDP+silane > MDP. There was no difference in surface roughness (P = 0.317) and surface topography among all tested groups. Zirconia treated with MDP-salt showed phosphorus peaks in addition to zirconia and alumina peaks. MDP-salt has zirconia priming properties, which improves bonding performance to resin cement.

Effect of CLA supplementation on immune function in young healthy volunteers.

OBJECTIVES: This study investigated the effect of dietary CLA supplementation (3g/day; 50:50 mix of the two major isomers) on the immune system and plasma lipids and glucose of healthy human (male and female) volunteers. DESIGN: Double-blind, randomized, reference-controlled study. SUBJECT AND INTERVENTION: A total of 28 healthy male and female participants aged 25-50 y received either high oleic sunflower oil (reference) or 50% CLA 9-11 and 50% CLA 10-12 CLA isomers (50:50 CLA-triglyceride form). The treatments were given as supplements in soft-gel capsules providing a total 3 g (6 x 500 mg capsules) per day in treatment groups for 12 weeks. A 12-week washout period followed the intervention period. RESULTS: Levels of plasma IgA and IgM were increased (P < 0.05 and 0.01 respectively), while plasma IgE levels were decreased (P < 0.05). CLA supplementation also decreased the levels of the proinflammatory cytokines, TNF-alpha and IL-1beta (P < 0.05), but increased the levels of the anti-inflammatory cytokine, IL-10 (P < 0.05). Another aspect of immune function, delayed type hypersensitivity (DTH) response, was decreased during and after CLA supplementation (P < 0.05). However, plasma glucose, lipids, lymphocyte phenotypic results were not affected significantly by CLA. CONCLUSION: This is the first study to show that CLA, a fatty acid naturally found in dairy and meat products, can beneficially affect immune function in healthy human volunteers. SPONSORSHIP: This study was supported by Loders-Croklaan, The Netherlands and SEERAD (Scottish Executive Environmental Rural and Agriculture Department).

Hormone replacement therapy can augment vascular relaxation in post-menopausal women with type 2 diabetes.

BACKGROUND: Diabetes is a major risk factor for coronary heart disease in women and event rates increase substantially after the menopause. Observational studies have suggested that estrogens may provide cardioprotection by regulating endothelial nitric oxide synthase. METHODS: In order to examine the effect of hormone replacement therapy (HRT) on endothelium-dependent and -independent vascular relaxation in post-menopausal women with type 2 diabetes, an open study was conducted in which gluteal biopsies were collected from 17 women before and after 6 months of transdermal 17 beta-estradiol (80 microg twice weekly) in combination with oral norethisterone (1 mg daily). Small arteries (<550 microm) were dissected from fat and mounted on a wire myograph for assessment of relaxation in response to acetylcholine (ACh), bradykinin (BK) and sodium nitroprusside (SNP). RESULTS: Maximal relaxation responses to ACh, BK and SNP in women with diabetes and non-diabetic control subjects were 52 +/- 8 versus 96 +/- 2% (P < 0.05), 76 +/- 7 versus 97 +/- 1%, (P < 0.05) and 91 +/- 2 versus 98 +/- 1% (P < 0.05) respectively. After 6 months of HRT, maximal relaxation responses to ACh, BK and SNP in women with diabetes (compared with pre-HRT) were: 88 +/- 4 (P < 0.05), 93 +/- 3 (P < 0.05) and 98 +/- 1% (P < 0.05) respectively. At baseline and after HRT, EC50 (concentration required to obtain 50% of maximum response) data exhibited similar changes. CONCLUSIONS: HRT had potentially beneficial effects on vascular relaxation. Data were consistent with improvements in endothelial function, vascular smooth muscle function, or both. Controlled studies are required to confirm and extend these findings.

Fatty acid status of women of reproductive age.

OBJECTIVE: Healthy foetal and infant development is dependent on an adequate maternal supply of essential and polyunsaturated fatty acids (PUFA). While there are published data on the fatty acid status of pregnant women, there are few on the status of non-pregnant women of reproductive age. The aims of this study were to test the hypotheses that the fatty acid status of non-pregnant women is affected by socio-economic status and anthropometric, behavioural and obstetric factors. DESIGN: Observational study METHODS: One-hundred and thirty-five women of child-bearing age (mean 29.8 y, s.d. 6.92) were invited to provide a blood sample and to answer a questionnaire, of whom 114 were included in the study. Plasma and red cell total fatty acids were measured as their methyl esters by gas chromatography mass spectrometry. RESULTS: On multivariate analyses, use of hormonal contraception was independently associated with lower plasma polyunsaturated fatty acids (difference between means -2.76, 95% confidence interval (-4.64, -0.88), P=0.0034), whereas cigarette smoking was associated with higher red cell oleic acid (0.74 (0.18, 1.29), P=0.0094). Fish intake was associated with higher red cell total n-3 fatty acids (0.62 (0.27, 0.85), P=0.0014). CONCLUSIONS: We have reported data on the range of the fatty acids of plasma and red blood cells (RBC) total lipids of 114 healthy women of reproductive age. These data provide further information on how socio-economic, anthropometric, behavioural and obstetric factors may be relevant to female and nutrition and health. SPONSORSHIP: University of Glasgow.

Changes in micronutrient concentrations following anti-inflammatory treatment in patients with gastrointestinal cancer.

Circulating concentrations of vitamin antioxidants (retinol, alpha-tocopherol, lutein, lycopene, alpha- and beta-carotene) and trace elements (zinc, copper, iron and selenium) plus carrier proteins (albumin, transferrin, caeruloplasmin) in gastrointestinal cancer patients (n = 12) with an inflammatory response (as demonstrated by an elevated C-reactive protein concentration) were compared with a control group (n = 12). Further, the effect of moderating the inflammatory response, using the anti-inflammatory agent ibuprofen, on these measurements was examined in the cancer group. The control and cancer groups were similar in terms of age, sex, and body mass index. However, the cancer group had significantly higher C-reactive protein concentrations (P < 0.001). Concentrations of vitamin antioxidants and trace elements (and carrier proteins) were significantly lower (P < 0.001), except copper (ceruloplasmin) which was significantly higher (P < 0.05). After anti-inflammatory treatment, there were small but significant increases in lutein, lycopene, and beta-carotene (P < 0.05) and in iron and selenium (P < 0.05), whereas ceruloplasmin decreased (P < 0. 05). The micronutrient concentrations in the cancer patients remained different from those in the control subjects. These results support the concept that the magnitude of inflammation plays an important role in the regulation of circulating concentrations of vitamin antioxidants and trace elements in patients with gastrointestinal cancer.

Dietary flavonols protect diabetic human lymphocytes against oxidative damage to DNA.

Diabetic patients have reduced antioxidant defenses and suffer from an increased risk of free radical-mediated diseases such as coronary heart disease. Epidemiological evidence has suggested that antioxidant dietary flavonoids may protect against heart disease, but a biological effect has yet to be demonstrated directly in humans. In this study, 10 stable type 2 diabetic patients were treated for 2 weeks on a low-flavonol diet and for 2 weeks on the same diet supplemented with 76-110 mg of flavonols (mostly quercetin) provided by 400 g of onions (and tomato sauce) and six cups of tea daily. Freshly collected lymphocytes were subjected to standard oxidative challenge with hydrogen peroxide, and DNA damage was measured by single-cell gel electrophoresis. Fasting plasma flavonol concentrations (measured by high-performance liquid chromatography) were 5.6 +/- 2.9 ng/ml on the low-flavonol diet and increased 12-fold to 72.1 +/- 15.8 ng/ml on the high-flavonol diet (P < 0.001). Oxidative damage to lymphocyte DNA was 220 +/- 12 on an arbitrary scale of 0-400 U on the low-flavonol diet and 192 +/- 14 on the high-flavonol diet (P = 0.037). This decrease was not accounted for by any change in the measurements of diabetic control (fasting plasma glucose or fructosamine) or by any change in the plasma levels of known antioxidants, including vitamin C, carotenoids, alpha-tocopherol, urate, albumin, and bilirubin. In conclusion, we have shown a biological effect of potential medical importance that appears to be associated with the absorption of dietary flavonols.

Acute-phase reactants and plasma trace element concentrations in non-small cell lung cancer patients and controls.

This study examined the effect of an acute-phase response on plasma trace element concentrations of non-small cell lung cancer (NSCLC) patients. In normal subjects (n = 13) and NSCLC patients (n = 22), fasting concentrations of albumin, C-reactive protein, the trace elements iron, zinc, copper, and selenium, and their associated proteins transferrin, albumin, ceruloplasmin, and glutathione peroxidase were measured. The NSCLC patients were subdivided into two equal groups depending on whether they had a C-reactive protein concentration < 35 mg/l (Group 1) or > 35 mg/l (Group 2). Circulating zinc, iron, and transferrin concentrations were significantly lower in NSCLC Group 1 than in the control group (p < 0.05). Circulating concentrations of iron, zinc, and the binding proteins transferrin and albumin were significantly lower in NSCLC Group 2 than in the control group and NSCLC Group 1 (zinc not significantly different) (p < 0.01). In contrast circulating concentrations of copper and its binding protein ceruloplasmin were significantly increased in NSCLC Group 2 compared with NSCLC Group 1 and the control group (p < 0.01). Additionally, plasma selenium and glutathione peroxidase concentrations were significantly lower (p < 0.05) in NSCLC Group 2 than in NSCLC Group 1 and the control group. In the NSCLC patients there were significant negative correlations between concentrations of C-reactive protein and iron, transferrin, zinc, albumin, and selenium (p < 0.05). Furthermore, there were also significant positive correlations between C-reactive protein and copper (r = 0.788, p < 0.001) and ceruloplasmin (r = 0.831, p < 0.001) concentrations. The presence of an acute-phase response has implications for the interpretation of circulating trace element concentrations, the status of patients with NSCLC, and supplementation with trace elements in patients with NSCLC.