Polyphenol and glycoalkaloid contents in potato cultivars grown in Luxembourg

The polyphenol (phenolic acids, flavanols and flavonols) and glycoalkaloid (α-chaconine and α-solanine) contents of potato tubers grown in Luxembourg were analyzed by UPLC–DAD and HPLC–MS/MS separately in peel (approx. 2 mm), outer (approx. 1 cm) and inner flesh. Polyphenol contents decreased from the peel via the outer to the inner flesh and differed among the cultivars. The cultivars Vitelotte and Luminella had the highest polyphenol contents (5202 and 572 μg/g dry weight (DW) in the outer flesh), whereas Charlotte and Bintje had the lowest contents (19.5 and 48.0 μg/g DW). Chlorogenic acid and its isomers (neo- and cryptochlorogenic acid) were the major polyphenols. Glycoalkaloid contents were highest in the peel and lowest in the inner flesh, values in the flesh were below guideline limits in all cultivars. In conclusion, potatoes contribute to the daily intake of polyphenols and their consumption, thereby, may have positive effects on health.     

Two-fold emission from the S-shell of PbSe/CdSe core/shell quantum dots

The optical properties of PbSe/CdSe core/shell quantum dots with core sizes smaller than 4 nm in the 5-300 K range are reported. The photoluminescence spectra show two peaks, which become increasingly separated in energy as the core diameter is reduced below 4 nm. It is shown that these peaks are due to intrinsic exciton transitions in each quantum dot, rather than emission from different quantum dot sub-ensembles. Most likely, the energy separation between the peaks is due to inter-valley coupling between the L-points of PbSe. The temperature dependence of the relative intensities of the peaks implies that the two emitting states are not in thermal equilibrium and that dark exciton states must play an important role.     

The influence of acetylsalicylic acid on cognitive processing: an event-related potentials study

The central effects of acetylsalicylic acid (ASA) are discussed controversially. In animal models, it has been shown that ASA can interact with the central serotonergic and catecholaminergic neuronal system. However, the relevance of this interaction for humans is still unknown. We performed a study on the influence of ASA on central cognitive processing. In 25 healthy subjects (age 21-56 years), visually evoked event-related potentials (ERP) and reaction time under IV ASA medication were recorded. ERP were evoked by an oddball paradigm. As compared to placebo, ASA decreased the latency of the P3 component significantly in a time interval of 20-40 min after administration. The latency of the N2 component was significantly decreased about 25 min after administration; the latency of the exogenous P2 component was not influenced by ASA. The mean choice reaction time was significantly decreased by ASA 35 min after administration. At this time point, there was a significant correlation between decrease in reaction time and increase in ASA plasma level. The data show that IV administration of ASA has an accelerating effect on the endogenous components of visual ERP and on reaction time. This finding suggests that ASA can influence central cognitive processing, possibly by ASA induced changes of neurotransmitters. Since serotonin can be released by ASA and serotonin release leads to a decrease of ERP latencies. we assume that ASA most likely influences cognitive processing via the central serotonergic transmitter system.     

Patient attitude as a function of disease state in multiple sclerosis

The present study investigated the attitude of 243 patients with Multiple Sclerosis (MS) as a function of their perceived disease state. Data was collected via a closed-format questionnaire developed through the Fishbein and Ajzen [1-3] Theory of Reasoned Action. Results indicated clearly that patients with MS are not an homogenous group and vary in characteristics across disease states and that disease state differentially affects the psycho-social attitudes of patients. Results also indicated that persons in remission were more positive in their attitude associated with their disease state than persons with a chronic progressive form of the disease.     

Butyrate-induced differentiation of Caco-2 cells is associated with apoptosis and early induction of p21Waf1/Cip1 and p27Kip1

BACKGROUND: Intestinal mucosal turnover is a process of proliferation, differentiation, and apoptosis; the mechanisms remain largely undefined. The purpose of our study was to (1) assess the relationship between apoptosis and enterocyte differentiation and (2) determine whether the cell-cycle inhibitors, p21Waf1/Cip1 and p27Kip1, or the apoptosis inhibitors, Bcl-2 and Bcl-XL, may be involved. METHODS: Gut-derived Caco-2 cells were treated with sodium butyrate. Apoptosis was assessed by Hoechst stain, DNA laddering, and annexin V assay; differentiation was determined by alkaline phosphatase and sucrase activity. RNA and protein were analyzed for expression of p21Waf1/Cip1, p27Kip1, and members of the Bcl-2 family. RESULTS: Treatment of Caco-2 cells with sodium butyrate resulted in the concomitant induction of both differentiation (increased alkaline phosphatase and sucrase activity) and apoptosis. Increased levels of p21Waf1/Cip1 and p27Kip1 mRNA and protein were detected at 24 hours, occurring before apoptosis or differentiation; decreased mRNA levels of Bcl-2 and Bcl-XL were noted at 24 hours. CONCLUSIONS: Differentiation and apoptosis occurred simultaneously in Caco-2 cells, suggesting that apoptosis may be linked to enterocyte differentiation. The induction of p21Waf1/Cip1 and p27Kip1 and the down-regulation of Bcl-2 and Bcl-XL further suggest a link between the cell-cycle mechanisms regulating enterocyte differentiation and apoptosis.     

Direct determination of the total fat content of butter and edible oil emulsions — an international collaborative study

A standard operating procedure for the direct determination of fat in butter and edible oil products involved the extraction of the fat from the sample, separation of the solvent–fat phase from the serum phase and transfer of the solvent–fat phase to a fat-collecting vessel. The solvent was removed by distillation or evaporation and the mass of extracted matter was determined gravimetrically. This method was studied collaboratively involving 13 laboratories and eight samples to determine precision estimates. Estimates of repeatability and reproducibility were 0.23 g per 100 g and 0.45 g per 100 g, respectively. The method is recommended for adoption as an international reference method.     

Beyond unfavorable thinking: The Illness Cognition Questionnaire for chronic diseases.

The literature on chronic diseases recognizes the role of illness cognition as a mediator between stress and illness. Few conceptualizations and instruments, however, give an indication of both unfavorable and favorable ways of adjusting to an uncontrollable long-term stressor, such as a chronic disease. The authors propose 3 generic illness cognitions that reflect different ways of reevaluating the inherently aversive character of a chronic condition: helplessness as a way of emphasizing the aversive meaning of the disease, acceptance as a way to diminish the aversive meaning, and perceived benefits as a way of adding a positive meaning to the disease. A self-report instrument, the Illness Cognition Questionnaire, was developed to assess these cognitions across different chronic diseases. The results support the reliable and valid assessment of these illness cognitions in patients with rheumatoid arthritis and multiple sclerosis and indicate the maladaptive function of helplessness and the adaptive function of acceptance and perceived benefits for the long-term physical and psychological health of patients with a chronic disease. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Thin film pseudomorphicAlAs/In0.53Ga0.47As/InAs resonant tunnellingdiodes integrated onto Si substrates

We report high peak-to-valley current ratio (PVR) resonant tunneling diodes (RTDs) bonded to silicon. Pseudomorphic AlAs/In_0.53Ga_0.47As/InAs resonant tunneling diode structures grown on semi-insulating InP with peak-to-valley current ratios as high as 30 at 300 K have been separated from the growth substrate and bonded to silicon substrates coated with Si₃N ₄, forming thin film devices. In addition, thin film multiple stack RTD structures have been bonded to silicon substrates. The I-V characteristics of both the single and multi-stacked thin film RTD's exhibit no signs of degradation after bonding to the host substrate. These results are the first successful demonstration of InP based electronics bonded to a silicon host substrate and enable the integration of RTDs with conventional silicon circuitry     

A comparison of 2 modes of administration of recombinant interleukin-2: continuous intravenous infusion alone versus subcutaneous administration plus interferon alpha in patients with advanced renal cell carcinoma

PURPOSE: To compare 2 treatment modalities with recombinant Interleukin-2 (rIL-2) for patients with advanced Renal Cell carcinoma (RCC): continuous intravenous infusion (CIV) alone versus subcutaneous (s/c) rIL-2 + Interferon-alpha (IFN-alpha). PATIENTS AND METHODS: Data have been collected on 425 patients with RCC, treated CIV rIL-2 alone, (225 patients), or rIL-2 by the s/c route (200 patients). Patients receiving s/c rIL-2 also received s/c IFN-alpha both drugs being administered on an outpatient basis. Patients receiving CIV rIL-2 were treated as inpatients. Patient eligibility criteria were similar on all studies, and included patients with progressive, advanced disease, but with an ambulatory performance status. RESULTS: The overall response rate for the CIV schedules was not significantly different from the s/c regimens: 15% (95% confidence limits (CL) 10-20%) vs 20% (95%CL 14-26%) with 4% CR in both approaches. Durable responses were seen in both CIV and s/c schedules and there was no evidence of a significant difference in survival in multivariate analysis. There was however an important shift in the toxicity profile. The s/c regimens do not induce a clinically detectable capillary leak syndrome, which is the dose limiting toxicity for CIV regimens. CONCLUSION: Although the introduction of CIV regimens of rIL-2 was a major step forward compared to high-dose bolus, because most patients could be treated in a normal oncology ward, the s/c schedule of rIL-2 + IFN-alpha offers the possibility of outpatient (home) therapy, with no evidence of a reduction in efficacy.     

Description of a coverslip holder for,and observations on,the critical point drying of cell cultures

The elimination of artefact during the preparation of cell cultures for scanning electron microscopy is difficult. Collapse of cellular projections, cytoplasmic cracks, perforations and fracturing of cell-cell processes and cell-substrate attachments occur during fixation, dehydration and critical point drying. Coating and storage may cause further artefact. A specimen holder which serves to minimize turbulence in the critical point dryer and which allows for the simultaneous processing of up to five coverslips, as well as a reproducible technique for the preparation of cell cultures are described.