An unexpected EEG course in Dravet syndrome

A puzzling EEG pattern combining frontal slow bi-tri spikes followed or not by slow waves when awake and activated by sleep with 5-10s discharges of 8-9Hz spikes in a minority of adolescents with Dravet syndrome (DS) was recorded in the context of stable seizure and cognitive status, and unchanged antiepileptic medication. Tonic seizures were frequently reported in patients with this EEG pattern (3/5). This EEG pattern could suggest that of Lennox-Gastaut syndrome (LGS) but it exhibits clear differences and therefore should not be considered as a change into LGS but as a previously overlooked unusual pattern in the adolescent course of DS.     

Extracellular calcium regulates parathyroid hormone-related peptide expression in osteoblasts and osteoblast progenitor cells

Parathyroid hormone-related peptide (PTHrP) has been shown to have anabolic effects on bone in women with postmenopausal osteoporosis. On the cellular level PTHrP promotes the recruitment of osteogenic cells and prevents apoptotic death of osteoblasts and osteocytes. The calcium concentration is considerably higher in the vicinity of resorbing osteoclasts than in the plasma. Therefore the osteoblasts are likely to be confronted by elevated extracellular calcium concentrations in the areas of resorptive activity. The present study was designed to assess the possibility that extracellular calcium could regulate PTHrP expression in osteoblastic cells. Adult human mesenchymal stem cells (hMSC) were cultured and differentiated by standard methods. The PTHrP release into the culture media was measured by an immunoradiometric assay and the expression of PTHrP, osteocalcin and Runx2 mRNA was assayed by real-time PCR. Increasing the extracellular calcium from 1 mM to 5 mM for 24 h resulted in a 4-6-fold increase in the PTHrP release. PTHrP mRNA was also increased by elevated calcium levels. The effect of calcium stimulation on PTHrP release could be seen within 60 min of treatment. The extracellular calcium sensing receptor (CaR) agonist neomycin mimicked the effects of calcium and the MEK/MAPK inhibitor PD98059 abolished the effect of calcium and neomycin. High extracellular calcium increased the mineralization of hMSC and the expression of osteocalcin, but this effect was not mimicked by neomycin. Our results show that in hMSC, elevated extracellular calcium levels increases both released PTHrP and PTHrP mRNA expression. The effect of calcium on PTHrP can be mimicked by activation of the CaR and can be diminished by inhibition of the MAPK signalling pathway.     

Identification of Novel Specific and General Inhibitors of the Three Major Human ATP-Binding Cassette Transporters P-gp,BCRP and MRP2 Among Registered Drugs

Purpose  To study the inhibition patterns of the three major human ABC transporters P-gp (ABCB1), BCRP (ABCG2) and MRP2 (ABCC2), using a dataset of 122 structurally diverse drugs. Methods  Inhibition was investigated in cellular and vesicular systems over-expressing single transporters. Computational models discriminating either single or general inhibitors from non-inhibitors were developed using multivariate statistics. Results  Specific (n = 23) and overlapping (n = 19) inhibitors of the three ABC transporters were identified. GF120918 and Ko143 were verified to specifically inhibit P-gp/BCRP and BCRP in defined concentration intervals, whereas the MRP inhibitor MK571 was revealed to inhibit all three transporters within one log unit of concentration. Virtual docking experiments showed that MK571 binds to the ATP catalytic site, which could contribute to its multi-specific inhibition profile. A computational model predicting general ABC inhibition correctly classified 80% of both ABC transporter inhibitors and non-inhibitors in an external test set. Conclusions  The inhibitor specificities of P-gp, BCRP and MRP2 were shown to be highly overlapping. General ABC inhibitors were more lipophilic and aromatic than specific inhibitors and non-inhibitors. The identified specific inhibitors can be used to delineate transport processes in complex experimental systems, whereas the multi-specific inhibitors are useful in primary ABC transporter screening in drug discovery settings. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.

Population health impact of cancer in Canada, 2001

Summary measures of population health that incorporate morbidity provide a new perspective for health policy and priority setting. Health-adjusted life years (HALYs) lost to a disease combine the impact of years of life lost to premature mortality and morbidity, measured as year-equivalents lost to reduced functioning. HALYs for 25 cancers were estimated from mortality and incidence in 2001 in Canada; population-attributable fractions were estimated for major risk factors contributing to these cancers. Results from this analysis indicate that Canadians would lose an estimated 905,000 health-adjusted years of life to cancer for 2001, including 771,000 to premature mortality and 134,000 to morbidity from incident cases (years discounted at 3 percent). Most of the estimated premature mortality was due to lung cancer; morbidity was largely due to breast, prostate and colorectal cancers. An estimated one quarter of HALYs lost to cancer were attributable to smoking and almost one quarter were attributable to alcohol consumption, lack of fruit and vegetables, obesity and physical inactivity combined. These results are a significant advance in measuring the population health impact of cancer in Canada because they incorporate morbidity as well as mortality. Key words: burden of disease, cancer, DALY, HALY, health status indicators, population health, quality of life, summary measures.     

Topical chemotherapy in human urothelial carcinoma explants: a novel translational tool for preclinical evaluation of experimental intravesical therapies

Background

Urothelial carcinoma (UC) is associated with a high local recurrence rate despite intravesical therapy. There is a lack of representative preclinical models for standardized testing of novel experimental therapies.

Objective

To develop an ex vivo model for human UC and to evaluate its ability to generate reproducible and reliable results when testing cytotoxic agents.

Design, setting, and participants

Normal human urothelium (NHU) and bladder UC explants were collected from patients treated at our institution. A total of 195 surgical explants were cultured on a gelatine matrix. Tissue viability was regularly assessed using nicotinamide adenine dinucleotide (NADH) diaphorase enzymehistochemistry. Topical paclitaxel (PTX) or mitomycin C (MMC) chemotherapy was performed in a subset of 45 UC specimens.

Intervention

All patients underwent radical cystectomy (RC) or primary transurethral resection (TUR) of a bladder UC.

Measurements

Triple immunofluorescence (pan-cytokeratin [pan-CK]; 4′,6-diamidin-2′-phenylindol-dihydrochloride [DAPI]; terminal deoxynucleotidyl transferase biotin-dUTP nick-end labelling [TUNEL]) and caspase-3 staining of paraffin sections was performed. Proliferation rates were assessed using Ki-67 labelling indices. Apoptosis (percent) was quantified in representative tissue areas to characterize culture stability and to assess antineoplastic effects.

Results and limitations

No signs of necrosis and no significant changes in apoptosis were observed during the first 12 d of culture. Of all explants, 88.5% were vital after 20 d. In a highly reproducible fashion, topical chemotherapy resulted in significantly increased apoptosis (37.4% [19.0–75.0%] for PTX and 36.2% [18.8–46.7%] for MMC) compared with controls (7.5% [3.0–26.8%]; p < 0.001]). No statistically significant difference was observed regarding the effects of the two chemotherapeutic agents (p = 0.119).

Conclusions

The presented human ex vivo model takes UC heterogeneity into account and serves as a valuable translational tool. It offers an attractive alternative to preclinical cell line experiments or animal models and may even be used for prospective toxicity and drug efficacy tests in individual patients.     

Structure?Activity Study of Dihydrocinnamic Acids and Discovery of the Potent FFA1 (GPR40) Agonist TUG-469

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