Mechanism of NaCl transport-stimulated prostaglandin formation in MDCK cells

Recently we have found that stimulation of NaCl transport in high-resistance MDCK cells enhances their prostaglandin formation. In the present study, we investigated the mechanisms by which prostaglandin formation could be linked to the ion transport in these cells. We found that stimulation of transport caused a transient stimulation of prostaglandin formation lasting 5-10 min. The rise in prostaglandin formation was paralleled by a rise of free intracellular arachidonic acid. Analysis of membrane lipids revealed that the rise of free arachidonic acid was paralleled by a loss of arachidonic acid from polyphosphoinositides. We failed to obtain indications for the stimulation of calcium-dependent phospholipase A2. However, we did obtain evidence that the incorporation of arachidonic acid into phospholipids was diminished during stimulation of ion transport, indicating a decreased rate of reesterification. Despite the fact that there was no significant fall in total cellular ATP on stimulation of ion transport, we found a high and transient rise of lactate production of the cells on stimulation of the ion transport indicating an alteration of the ADP/ATP ratio. Moreover, prostaglandin formation and lactate formation were linearly correlated in this situation. When glucose utilization was inhibited by mannoheptulose, the rise in lactate formation was abolished, whereas that of PG formation was unaltered, indicating that lactate formation and prostaglandin formation were not causally linked on stimulation of ion transport. Our results suggest that an increase in the rate of sodium chloride transport by MDCK cells stimulates formation by an inhibition of reesterification of free arachidonic acid.(ABSTRACT TRUNCATED AT 250 WORDS

Copper-based Dye-sensitized Solar Cells with Quasi-Solid Nano Cellulose Composite Electrolytes

The study presented describes the preparation of solvent-free nano composite gel electrolytes in combination with  copper(I)-based dye-sensitized solar cells (DSSCs). The electrolytes comprise poly(ethylene oxide) (PEO) and cellulose nano crystals (CNCs) and an I 3 – /I – redox shuttle. The quasi-solid-state DSSCs show increased photoconversion performance with increased amount of CNC in the electrolyte. DSSC performances measured on the day that the devices are fabricated show that when the electrolyte is composed of 80% CNC, a cell efficiency of 1.09% is reached compared to 1.16% using a standard liquid I 3 – /I – electrolyte. DSSCs containing the nano composites and the copper(I)-based dye show robust stability over time, and after 60 days, DSSCs with the PEO/CNC/I 3 – /I – electrolyte outperform those containing the liquid electrolyt

Swath-ms: a new data independent acquisition LC-MS methodology for quantitative complete proteome analysis

Comunicaciones a congreso

Bias-voltage dependence of the magneto-resistance in ballistic vacuum tunneling: Theory and application to planar Co(0001) junctions

Motivated by first-principles results for jellium and by surface-barrier shapes that are typically used in electron spectroscopies, the bias voltage in ballistic vacuum tunneling is treated in a heuristic manner. The presented approach leads in particular to a parameterization of the tunnel-barrier shape, while retaining a first-principles description of the electrodes. The proposed tunnel barriers are applied to Co(0001) planar tunnel junctions. Besides discussing main aspects of the present scheme, we focus in particular on the absence of the zero-bias anomaly in vacuum tunneling.Comment: 19 pages with 8 figure

Versican in inflammation and tissue remodelling: the impact on lung disorders.

Versican is a proteoglycan that has many different roles in tissue homeostasis and inflammation. The biochemical structure is comprised of four different types of the core protein with attached glycosaminoglycans that can be sulphated to various extents and has the capacity to regulate differentiation of different cell types, migration, cell adhesion, proliferation, tissue stabilization and inflammation. Versican's regulatory properties are of importance during both homeostasis and changes that lead to disease progression. The glycosaminoglycans that are attached to the core protein are of the chondroitin sulfate/dermatan sulfate type and are known to be important in inflammation through interactions with cytokines and growth factors. For a more complex understanding of versican it is of importance to study the tissue niche, where the wound healing process in both healthy and diseased conditions take place. In previous studies our group has identified changes in the amount of the multifaceted versican in chronic lung disorders such as asthma, chronic obstructive pulmonary disease and bronchiolitis obliterans syndrome, which could be a result of pathologic, transforming growth factor β driven, on-going remodelling processes. Reversely, the context of versican in its niche is of great importance since versican has been reported to have a beneficial role in other contexts e.g. emphysema. Here we explore the vast mechanisms of versican in healthy lung and in lung disorders

Patients' initial steps to cancer diagnosis in Denmark, England and Sweden: what can a qualitative, cross-country comparison of narrative interviews tell us about potentially modifiable factors?

OBJECTIVES: To illuminate patterns observed in International Cancer Benchmarking Programme studies by extending understanding of the various influences on presentation and referral with cancer symptoms. DESIGN: Cross-country comparison of Denmark, England and Sweden with qualitative analysis of in-depth interview accounts of the prediagnostic process in lung or bowel cancer. PARTICIPANTS: 155 women and men, aged between 35 and 86 years old, diagnosed with lung or bowel cancer in 6 months before interview. SETTING: Participants recruited through primary and secondary care, social media and word of mouth. Interviews collected by social scientists or nurse researchers during 2015, mainly in participants' homes. RESULTS: Participants reported difficulties in interpreting diffuse bodily sensations and symptoms and deciding when to consult. There were examples of swift referrals by primary care professionals in all three countries. In all countries, participants described difficulty deciding if and when to consult, highlighting concerns about access to general practitioner appointments and overstretched primary care services, although this appears less prominent in the Swedish data. It was not unusual for there to be more than one consultation before referral and we noted two distinct patterns of repeated consultation: (1) situations where the participant left the primary care consultation with a plan of action about what should happen next; (2) participants were unclear about under which conditions to return to the doctors. This second pattern sometimes extended over many weeks during which patients described uncertainty, and sometimes frustration, about if and when they should return and whether there were any other feasible investigations. The latter pattern appeared more evident in the interviews in England and Denmark than Sweden. CONCLUSION: We suggest that if clear action plans, as part of safety netting, were routinely used in primary care consultations then uncertainty, false reassurance and the inefficiency and distress of multiple consultations could be reduced

Gene expression profiling in primary breast cancer distinguishes patients developing local recurrence after breast-conservation surgery, with or without postoperative radiotherapy

Introduction Some patients with breast cancer develop local recurrence after breast-conservation surgery despite postoperative radiotherapy, whereas others remain free of local recurrence even in the absence of radiotherapy. As clinical parameters are insufficient for identifying these two groups of patients, we investigated whether gene expression profiling would add further information. Methods We performed gene expression analysis (oligonucleotide arrays, 26,824 reporters) on 143 patients with lymph node-negative disease and tumor-free margins. A support vector machine was employed to build classifiers using leave-one-out cross-validation. Results Within the estrogen receptor-positive (ER+) subgroup, the gene expression profile clearly distinguished patients with local recurrence after radiotherapy (n = 20) from those without local recurrence (n = 80 with or without radiotherapy). The receiver operating characteristic (ROC) area was 0.91, and 5,237 of 26,824 reporters had a P value of less than 0.001 (false discovery rate = 0.005). This gene expression profile provides substantially added value to conventional clinical markers (for example, age, histological grade, and tumor size) in predicting local recurrence despite radiotherapy. Within the ER- subgroup, a weaker, but still significant, signal was found (ROC area = 0.74). The ROC area for distinguishing patients who develop local recurrence from those who remain local recurrence-free in the absence of radiotherapy was 0.66 (combined ER+/ER-). Conclusion A highly distinct gene expression profile for patients developing local recurrence after breast-conservation surgery despite radiotherapy has been identified. If verified in further studies, this profile might be a most important tool in the decision making for surgery and adjuvant therapy