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This work addresses the pH-triggered distribution and relocation of charge-stabilized gold nanoparticles (AuNPs) incorporated into strong polyelectrolyte brushes. Brush/particle composite materials were investigated under aqueous conditions and at different humidities using neutron and X-ray reflectivity, respectively. X-ray reflectivity measurements complement neutron reflectivity measurements and reveal results that could not be observed by neutron reflectivity measurements. Both methods allow scanning the particle density profile, but due to different contrasts, they are sensitive to different regions within the brush. More specifically, 3-mercaptopropionic acid (MPA)-coated AuNPs were incorporated into poly-[2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) polyelectrolyte brushes at different pH values. The pH value triggers a change in the AuNP surface charge caused by the pH-sensitivity of the MPA ligands, while the charge of the PMETAC brush is not affected by pH variations. The particle number density as well as the particle distribution depend strongly on the pH value of the incubation medium: a rather non-homogeneous assembly (2D assembly) is found when the PMETAC brush is incubated in AuNP suspension at pH 4, while a more homogeneous assembly (3D assembly) is found when the PMETAC brush is incubated in AuNP suspension at pH 8. The main factor dominating the formation of 2D or 3D assembly is assigned to the particle-particle interaction and not to the particle-polymer interaction. No significant relocation of AuNPs within the brush can be found by changing the environmental conditions. The control of particle amount and distribution within the polymer brush has a strong impact on the optical properties of those composite materials, which is crucial for the fabrication of colorimetric sensors.

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OBJECTIVE: To compare the effects of tibolone and conjugated equine oestrogens continuously combined with medroxyprogesterone acetate on bleeding rates, quality of life (QoL) and tolerability. DESIGN: A double-blind, randomised comparative trial. SETTING: Thirty-seven centres in six European countries. POPULATION: Five hundred and one postmenopausal women, under 65 years of age with an intact uterus. INTERVENTIONS: For 12 months, women received daily treatment with tibolone 2.5 mg (n = 250), or conjugated equine oestrogens 0.625 mg continuously combined with medroxyprogesterone acetate 5 mg (CEE-MPA, n = 251). MAIN OUTCOME MEASURES: The primary outcome was vaginal bleeding rate during cycles 4-6. The secondary outcomes were vaginal bleeding rate during cycles 1-3, 7-9 and 10-13, cumulative bleeding rate, QoL, wellbeing, climacteric symptoms, urogenital complaints and tolerability. RESULTS: Treatment with tibolone led to a significantly lower bleeding rate during cycles 4-6 compared with CEE-MPA (15.0% vs 26.9%; P = 0.004); there was a similar difference during cycles 1-3. Both treatments improved QoL, wellbeing, climacteric symptoms and urogenital complaints. By intent-to-treat analysis, tibolone significantly improved sexual drive, interest and/or performance, compared with CEE-MPA at 12 months (P = 0.017). Although both treatments were well tolerated, there was a significantly lower incidence of breast tenderness with tibolone than CEE-MPA (2.4% vs 17.1%; P < 0.001). CONCLUSION: The vaginal bleeding rate during cycles 4-6 was significantly lower in women using tibolone. Both treatments improved QoL, wellbeing, climacteric symptoms and urogenital symptoms. Breast tenderness was significantly less frequent with tibolone.

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OBJECTIVE: To compare the effects of two postmenopausal regimens on menopausal symptoms, bleeding episodes, side effects and acceptability. DESIGN: Double-blind, randomised controlled trial. SETTING: Twenty-nine sites in Denmark, nine in Norway and six in Sweden. PARTICIPANTS: Four hundred and thirty-seven postmenopausal women with menopausal complaints. None of these women had had a hysterectomy. INTERVENTIONS: Daily treatment with tibolone 2.5 mg (n = 218) or 17beta-oestradiol 2 mg plus norethisterone acetate 1 mg (E2/NETA) (n = 219). MAIN OUTCOME MEASURES: Hot flushes, sweating episodes, vaginal dryness, assessment of sexual life and bleeding patterns; at baseline and after 4, 12, 24 and 48 weeks. RESULTS: Treatment with either preparation significantly reduced mean scores for hot flushes, sweating episodes and vaginal dryness. The overall discontinuation rate was 28% (tibolone 25%, E2/NETA 31%; P = 0.14), mostly during the first six months. There was a markedly lower cumulative incidence of bleeding or spotting episodes with tibolone compared with E2/NETA (P < 0.0001), mainly during the first six treatment cycles. CONCLUSIONS: Both tibolone and E2/NETA effectively alleviate menopausal symptoms. However, tibolone caused significantly fewer bleeding or spotting episodes, which were reflected by lower overall rates of bleeding, as well as lower drop-out rates due to bleeding.

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A case of traumatic rupture of a normal spleen in a complicated delivery is presented. The etiology of splenic rupture and therapeutic aspects of this unusual occurrence are discussed. It is pointed out that a violent expression of the fetus might be dangerous for the mother.

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