125 research outputs found
Does working memory training have to be adaptive?
This study tested the common assumption that, to be most effective, working memory (WM) training should be adaptive (i.e., task difficulty is adjusted to individual performance). Indirect evidence for this assumption stems from studies comparing adaptive training to a condition in which tasks are practiced on the easiest level of difficulty only [cf. Klingberg (Trends Cogn Sci 14:317-324, 2010)], thereby, however, confounding adaptivity and exposure to varying task difficulty. For a more direct test of this hypothesis, we randomly assigned 130 young adults to one of the three WM training procedures (adaptive, randomized, or self-selected change in training task difficulty) or to an active control group. Despite large performance increases in the trained WM tasks, we observed neither transfer to untrained structurally dissimilar WM tasks nor far transfer to reasoning. Surprisingly, neither training nor transfer effects were modulated by training procedure, indicating that exposure to varying levels of task difficulty is sufficient for inducing training gains
IGFBP-rP1, a potential molecule associated with colon cancer differentiation
<p>Abstract</p> <p>Background</p> <p>In our previous studies, we have demonstrated that insulin-like growth factor binding protein-related protein1 (IGFBP-rP1) played its potential tumor suppressor role in colon cancer cells through apoptosis and senescence induction. In this study, we will further uncover the role of IGFBP-rP1 in colon cancer differentiation and a possible mechanism by revealing responsible genes.</p> <p>Results</p> <p>In normal colon epithelium, immunohistochemistry staining detected a gradient IGFBP-rP1 expression along the axis of the crypt. IGFBP-rP1 strongly expressed in the differentiated cells at the surface of the colon epithelium, while weakly expressed at the crypt base. In colon cancer tissues, the expression of IGFBP-rP1 correlated positively with the differentiation status. IGFBP-rP1 strongly expressed in low grade colorectal carcinoma and weakly expressed in high grade colorectal carcinoma. In vitro, transfection of PcDNA3.1(IGFBP-rP1) into RKO, SW620 and CW2 cells induced a more pronounced anterior-posterior polarity morphology, accompanied by upregulation with alkaline phosphatase (AKP) activity. Upregulation of carcino-embryonic antigen (CEA) was also observed in SW620 and CW2 transfectants. The addition of IGFBP-rP1 protein into the medium could mimic most but not all effects of IGFBP-rP1 cDNA transfection. Seventy-eight reproducibly differentially expressed genes were detected in PcDNA3.1(IGFBP-rP1)-RKO transfectants, using Affymetrix 133 plus 2.0 expression chip platform. Directed Acyclic Graph (DAG) of the enriched GO categories demonstrated that differential expression of the enzyme regulator activity genes together with cytoskeleton and actin binding genes were significant. IGFBP-rP1 could upreguate Transgelin (TAGLN), downregulate SRY (sex determining region Y)-box 9(campomelic dysplasia, autosomal sex-reversal) (SOX9), insulin receptor substrate 1(IRS1), cyclin-dependent kinase inhibitor 2B (p15, inhibits CDK4) (CDKN2B), amphiregulin(schwannoma-derived growth factor) (AREG) and immediate early response 5-like(IER5L) in RKO, SW620 and CW2 colon cancer cells, verified by Real time Reverse Transcription Polymerase Chain Reaction (rtRT-PCR). During sodium butyrate-induced Caco2 cell differentiation, IGFBP-rP1 was upregulated and the expression showed significant correlation with the AKP activity. The downregulation of IRS1 and SOX9 were also induced by sodium butyrate.</p> <p>Conclusion</p> <p>IGFBP-rP1 was a potential key molecule associated with colon cancer differentiation. Downregulation of IRS1 and SOX9 may the possible key downstream genes involved in the process.</p
Temporal resolution of protein–protein interactions in the live-cell plasma membrane
We have recently devised a method to quantify interactions between a membrane protein (“bait”) and a fluorophore-labeled protein (“prey”) directly in the live-cell plasma membrane (Schwarzenbacher et al. Nature Methods 5:1053–1060 2008). The idea is to seed cells on surfaces containing micro-patterned antibodies against the exoplasmic domain of the bait, and monitor the co-patterning of the fluorescent prey via fluorescence microscopy. Here, we characterized the time course of bait and prey micropattern formation upon seeding the cells onto the micro-biochip. Patterns were formed immediately after contact of the cells with the surface. Cells were able to migrate over the chip surface without affecting the micropattern contrast, which remained constant over hours. On single cells, bait contrast may be subject to fluctuations, indicating that the bait can be released from and recaptured on the micropatterns. We conclude that interaction studies can be performed at any time-point ranging from 5 min to several hours post seeding. Monitoring interactions with time opens up the possibility for new assays, which are briefly sketched in the discussion section
Stage II/III rectal cancer with intermediate response to preoperative radiochemotherapy: Do we have indications for individual risk stratification?
<p>Abstract</p> <p>Background</p> <p>Response to preoperative radiochemotherapy (RCT) in patients with locally advanced rectal cancer is very heterogeneous. Pathologic complete response (pCR) is accompanied by a favorable outcome. However, most patients show incomplete response. The aim of this investigation was to find indications for risk stratification in the group of intermediate responders to RCT.</p> <p>Methods</p> <p>From a prospective database of 496 patients with rectal adenocarcinoma, 107 patients with stage II/III cancers and intermediate response to preoperative 5-FU based RCT (ypT2/3 and TRG 2/3), treated within the German Rectal Cancer Trials were studied. Surgical treatment comprised curative (R0) total mesorectal excision (TME) in all cases. In 95 patients available for statistical analyses, residual transmural infiltration of the mesorectal compartment, nodal involvement and histolologic tumor grading were investigated for their prognostic impact on disease-free (DFS) and overall survival (OS).</p> <p>Results</p> <p>Residual tumor transgression into the mesorectal compartment (ypT3) did not influence DFS and OS rates (p = 0.619, p = 0.602, respectively). Nodal involvement after preoperative RCT (ypN1/2) turned out to be a valid prognostic factor with decreased DFS and OS (p = 0.0463, p = 0.0236, respectively). Persistent tumor infiltration of the mesorectum (ypT3) and histologic tumor grading of residual tumor cell clusters were strongly correlated with lymph node metastases after neoadjuvant treatment (p < 0.001).</p> <p>Conclusions</p> <p>Advanced transmural tumor invasion after RCT does not affect prognosis when curative (R0) resection is achievable. Residual nodal status is the most important predictor of individual outcome in intermediate responders to preoperative RCT. Furthermore, ypT stage and tumor grading turn out to be additional auxiliary factors. Future clinical trials for risk-adapted adjuvant therapy should be based on a synopsis of clinicopathologic parameters.</p
Functional analysis of genes involved in the biosynthesis of isoprene in Bacillus subtilis
In comparison to other bacteria Bacillus subtilis emits the volatile compound isoprene in high concentrations. Isoprene is the smallest representative of the natural product group of terpenoids. A search in the genome of B. subtilis resulted in a set of genes with yet unknown function, but putatively involved in the methylerythritol phosphate (MEP) pathway to isoprene. Further identification of these genes would give the possibility to engineer B. subtilis as a host cell for the production of terpenoids like the valuable plant-produced drugs artemisinin and paclitaxel. Conditional knock-out strains of putative genes were analyzed for the amount of isoprene emitted. Differences in isoprene emission were used to identify the function of the enzymes and of the corresponding selected genes in the MEP pathway. We give proof on a biochemical level that several of these selected genes from this species are involved in isoprene biosynthesis. This opens the possibilities to investigate the physiological function of isoprene emission and to increase the endogenous flux to the terpenoid precursors, isopentenyl diphosphate and dimethylallyl diphosphate, for the heterologous production of more complex terpenoids in B. subtilis
Performance of the CMS Cathode Strip Chambers with Cosmic Rays
The Cathode Strip Chambers (CSCs) constitute the primary muon tracking device
in the CMS endcaps. Their performance has been evaluated using data taken
during a cosmic ray run in fall 2008. Measured noise levels are low, with the
number of noisy channels well below 1%. Coordinate resolution was measured for
all types of chambers, and fall in the range 47 microns to 243 microns. The
efficiencies for local charged track triggers, for hit and for segments
reconstruction were measured, and are above 99%. The timing resolution per
layer is approximately 5 ns
Association of a Deletion of GSTT2B with an Altered Risk of Oesophageal Squamous Cell Carcinoma in a South African Population: A Case-Control Study
Polymorphisms in the Glutathione S-transferase genes are associated with altered risks in many cancers, but their role in oesophageal cancer is unclear. Recently a 37-kb deletion polymorphism of GSTT2B that reduces expression of GSTT2 has been described. We evaluated the influence of the GSTT1 and GSTT2B deletion polymorphisms, and the GSTP1 Ile105Val polymorphism (rs1695) on susceptibility to oesophageal squamous cell carcinoma (OSCC) in the Black and Mixed Ancestry populations of South Africa.The GSTT1, GSTT2B and GSTP1 variants were genotyped in 562 OSCC cases and 907 controls, and tested for association with OSCC and for interaction with smoking and alcohol consumption. Linkage disequilibrium (LD) between the deletions at GSTT1 and GSTT2B was determined, and the haplotypes tested for association with OSCC. Neither the GSTT1 deletion nor the GSTP1 Ile105Val polymorphism was associated with OSCC risk in the Black or Mixed Ancestry populations. The GSTT2B deletion was not associated with OSCC risk in the Black population, but was associated with reduced risk of OSCC in the Mixed Ancestry population (OR=0.71; 95% CI 0.57-0.90, p=0.004). Case-only analysis showed no interaction between the GST polymorphisms and smoking or alcohol consumption. LD between the neighboring GSTT1 and GSTT2B deletions was low in both populations (r(2)(Black)=0.04; r(2)(MxA)=0.07), thus these deletions should be assessed independently for effects on disease risk.Although there was no association between the GSTT1 deletion polymorphism or the GSTP1 Ile105Val polymorphism with OSCC, our results suggest that the presence of the recently described GSTT2B deletion may have a protective effect on the risk of OSCC in the Mixed Ancestry South African population. This is the first report of the contribution of the GSTT2B deletion to cancer risk
Molecular biology of breast cancer metastasis: Inflammatory breast cancer: clinical syndrome and molecular determinants
Inflammatory breast cancer (IBC) is an aggressive form of locally advanced breast cancer (LABC) that effects approximately 5% of women with breast cancer annually in the USA. It is a clinically and pathologically distinct form of LABC that is particularly fast growing, invasive, and angiogenic. Nearly all women have lymph node involvement at the time of diagnosis, and approximately 36% have gross distant metastases. Despite recent advances in multimodality treatments, the prognosis of patients with IBC is poor, with a median disease-free survival of less than 2.5 years. Recent work on the genetic determinants that underlie the IBC phenotype has led to the identification of genes that are involved in the development and progression of this disease. This work has been aided by the establishment of primary human cell lines and animal models. These advances suggest novel targets for future interventions in the diagnosis and treatment of IBC
Cardiovasc Diabetol
BACKGROUND: Advanced glycation end-products play a role in diabetic vascular complications. Their optical properties allow to estimate their accumulation in tissues by measuring the skin autofluorescence (SAF). We searched for an association between SAF and major adverse cardiovascular events (MACE) incidence in subjects with Type 1 Diabetes (T1D) during a 7 year follow-up. METHODS: During year 2009, 232 subjects with T1D were included. SAF measurement, clinical [age, sex, body mass index (BMI), comorbidities] and biological data (HbA1C, blood lipids, renal parameters) were recorded. MACE (myocardial infarction, stroke, lower extremity amputation or a revascularization procedure) were registered at visits in the center or by phone call to general practitioners until 2016. RESULTS: The participants were mainly men (59.5%), 51.5 +/- 16.7 years old, with BMI 25.0 +/- 4.1 kg/m(2), diabetes duration 21.5 +/- 13.6 years, HbA1C 7.6 +/- 1.1%. LDL cholesterol was 1.04 +/- 0.29 g/L, estimated Glomerular Filtration Rates (CKD-EPI): 86.3 +/- 26.6 ml/min/1.73 m(2). Among these subjects, 25.1% were smokers, 45.3% had arterial hypertension, 15.9% had elevated AER (>/= 30 mg/24 h), and 9.9% subjects had a history of previous MACE. From 2009 to 2016, 22 patients had at least one new MACE: 6 myocardial infarctions, 1 lower limb amputation, 15 revascularization procedures. Their SAF was 2.63 +/- 0.73 arbitrary units (AU) vs 2.08 +/- 0.54 for other patients (p = 0.002). Using Cox-model, after adjustment for age (as the scale time), sex, diabetes duration, BMI, hypertension, smoking status, albumin excretion rates, statin treatment and a previous history of MACE, higher baseline levels of SAF were significantly associated with an increased risk of MACE during follow-up (HR = 4.13 [1.30-13.07]; p = 0.02 for 1 AU of SAF) and Kaplan-Meier curve follow-up showed significantly more frequent MACE in group with SAF upper the median (p = 0.001). CONCLUSION: A high SAF predicts MACE in patients with T1D
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