Performance-based Tools for Assessing Functional Performance in Individuals with Mild Cognitive Impairment

Background: It is now recognized that individuals with mild cognitive impairment (MCI) face subtle functional declines that can compromise performance in everyday tasks. However, it is still not clear how to capture these declines in the clinical setting. Thus, the goal of this study was to conduct a scoping review to identify performance-based tools for which the psychometric properties have been evaluated with the MCI population. Methods: A scoping review of the scientific literature was performed with the guidance of a health science librarian in searching the MEDLINE, PsychINFO, CINAHL, and EMBASE databases from their inception until May 2014. Results: Nine performance-based tools assessing functional performance in individuals with MCI have been identified in the literature. While construct and content validity have been extensively reported, only two tools provided data on reliability. Conclusion: Considering that functional decline is part of the normal aging process, it might be challenging to differentiate normal from pathological functional decline in this population. Functional measurement tools might be very sensitive to capture these subtle changes. Although no recommendations can be proposed at this point on a specific tool to assess functional performance in MCI, research in this area is beginning to identify the elements that should be taken into consideration when choosing a tool

Diagnosis of Pancreatic Ductal Adenocarcinoma and Chronic Pancreatitis by Measurement of microRNA Abundance in Blood and Tissue

A solid process for diagnosis could have a substantial impact on the successful treatment of pancreatic cancer, for which currently mortality is nearly identical to incidence. Variations in the abundance of all microRNA molecules from peripheral blood cells and pancreas tissues were analyzed on microarrays and in part validated by real-time PCR assays. In total, 245 samples from two clinical centers were studied that were obtained from patients with pancreatic ductal adenocarcinoma or chronic pancreatitis and from healthy donors. Utilizing the minimally invasive blood test, receiver operating characteristic (ROC) curves and the corresponding area under the curve (AUC) analysis demonstrated very high sensitivity and specificity of a distinction between healthy people and patients with either cancer or chronic pancreatitis; respective AUC values of 0.973 and 0.950 were obtained. Confirmative and partly even more discriminative diagnosis could be performed on tissue samples with AUC values of 1.0 and 0.937, respectively. In addition, discrimination between cancer and chronic pancreatitis was achieved (AUC = 0.875). Also, several miRNAs were identified that exhibited abundance variations in both tissue and blood samples. The results could have an immediate diagnostic value for the evaluation of tumor reoccurrence in patients, who have undergone curative surgical resection, and for people with a familial risk of pancreatic cancer

Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation and function and EBV immunity

Background Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphoinositide 3-kinase (PI3K), result in hyperactivation of the PI3K–AKT–mechanistic target of rapamycin pathway and underlie a novel inborn error of immunity. Affected subjects exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or cytomegalovirus infection, and increased incidence of B-cell lymphoproliferation, lymphoma, or both. Mechanisms underlying disease pathogenesis remain unknown. Objective Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in patients with PIK3CD GOF mutations, identify key molecules required for cell-mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this and other EBV-opathies. Methods We studied the consequences of PIK3CD GOF mutations on the generation, differentiation, and function of CD8+ T cells and natural killer (NK) cells, which are implicated in host defense against infection with herpesviruses, including EBV. Results PIK3CD GOF total and EBV-specific CD8+ T cells were skewed toward an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion and increased susceptibility to reactivation-induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF mutations. NK cells in patients with PIK3CD GOF mutations also exhibited perturbed expression of differentiation-associated molecules. Both CD8+ T and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, programmed death ligand 1/2, and CD70. Conclusions PIK3CD GOF mutations aberrantly induce exhaustion, senescence, or both and impair cytotoxicity of CD8+ T and NK cells. These defects might contribute to clinical features of affected subjects, such as impaired immunity to herpesviruses and tumor surveillance

New strategy of a two-step radiosynthesis of [F-18]fluoropyridine-based maleimide-containing prosthetic groups for labelling of peptides and proteins

Objectives The use of thiol-reactive groups allows the introduction of fluorine-18 in a peptide or protein with cysteine residues, and different radiofluorinated maleimide-containing prosthetic groups have been described in the literature. All compounds were, however, prepared by a two- or three-step synthesis with an overall reaction time of at least 70 minutes. The aim of this work was to improve the radiosynthesis of maleimide-containing compounds with reduced reaction steps by using a new synthetic route via protection of the maleimide function. This was first done here with the example of 1-[3-(2-[18F]fluoropyridin-3-oxy)propyl]pyrrol-2,5-dione ([18F]FPyME) which is usually prepared in three steps [1]. Methods The first step for the preparation of the precursor was a Williamson reaction to form the ether from 3-hydroxy-2-nitropyridine with 1,3-dibromopropane. In a parallel process maleimide was protected with 2,5-dimethylfurane via a Diels-Alder-reaction. These two products were combined by N-alkylation to form the precursor. The radiosynthesis includes the introduction of fluorine-18 by nucleophilic substitution of the nitro group followed by deprotection of the maleimide function (see fig. 1). The reaction steps were optimized with regard to temperature, time and solvents. Results The optimal conditions for the n.c.a. radiofluorination were identified at a temperature of 80 °C in DMSO and a reaction time of 5 minutes, resulting in a radiochemical yield of about 29 ± 3 %. At higher temperatures the deprotection of the precursor and the labelled compound come to the fore and thereby the decomposition of the unprotected maleimide occurs due to the basic reaction conditions. The deprotection step was quantitatively carried out within 15 minutes. [18F]FPyME was isolated by HPLC to provide the pure prosthetic group which was directly used for effective peptide labelling. The overall synthesis time was about 60 minutes and the overall radiochemical yield was about 20 %. Conclusions The described synthetic route provides the possibility to gain a variety of further [18F]fluoropyridine-based maleimide-containing compounds in two steps only. In addition, this method offers to be performed as one-pot synthesis. Acknowledgements References [1] de Bruin B. et al. (2006) Bioconjugate Chem., 16, 406-420

Transcriptional variations in the wider peritumoral tissue environment of pancreatic cancer

Transcriptional profiling was performed on 452 RNA preparations isolated from various types of pancreatic tissue from tumour patients and healthy donors, with a particular focus on peritumoral samples. Pancreatic ductal adenocarcinomas (PDAC) and cystic tumours were most different in these non-tumorous tissues surrounding them, whereas the actual tumours exhibited rather similar transcript patterns. The environment of cystic tumours was transcriptionally nearly identical to normal pancreas tissue. In contrast, the tissue around PDAC behaved a lot like the tumour, indicating some kind of field defect, while showing far less molecular resemblance to both chronic pancreatitis and healthy tissue. This suggests that the major pathogenic difference between cystic and ductal tumours may be due to their cellular environment rather than the few variations between the tumours. Lack of correlation between DNA methylation and transcript levels makes it unlikely that the observed field defect in the peritumoral tissue of PDAC is controlled to a large extent by such epigenetic regulation. Functionally, a strikingly large number of autophagy-related transcripts was changed in both PDAC and its peritumoral tissue, but not in other pancreatic tumours. A transcription signature of 15 autophagy-related genes was established that permits a prognosis of survival with high accuracy and indicates the role of autophagy in tumour biology

Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation and function and EBV immunity

BACKGROUND: Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphoinositide 3-kinase (PI3K), result in hyperactivation of the PI3K-AKT-mechanistic target of rapamycin pathway and underlie a novel inborn error of immunity. Affected subjects exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or cytomegalovirus infection, and increased incidence of B-cell lymphoproliferation, lymphoma, or both. Mechanisms underlying disease pathogenesis remain unknown. OBJECTIVE: Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in patients with PIK3CD GOF mutations, identify key molecules required for cell-mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this and other EBV-opathies. METHODS: We studied the consequences of PIK3CD GOF mutations on the generation, differentiation, and function of CD8+ T cells and natural killer (NK) cells, which are implicated in host defense against infection with herpesviruses, including EBV. RESULTS: PIK3CD GOF total and EBV-specific CD8+ T cells were skewed toward an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion and increased susceptibility to reactivation-induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF mutations. NK cells in patients with PIK3CD GOF mutations also exhibited perturbed expression of differentiation-associated molecules. Both CD8+ T and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, programmed death ligand 1/2, and CD70. CONCLUSIONS: PIK3CD GOF mutations aberrantly induce exhaustion, senescence, or both and impair cytotoxicity of CD8+ T and NK cells. These defects might contribute to clinical features of affected subjects, such as impaired immunity to herpesviruses and tumor surveillance.status: publishe

Barplots detailing intensity values recorded for particular miRNAs that exhibited significant expression variations.

<p>Only one typical result each is shown for blood and tissue. In the two panels on the left, the intensity values of miR-320a in blood samples are presented. The two panels to the right show the values of miRNA-103 as recorded in tissue samples. The horizontal lines in each panel represent the respective median.</p

ROC curves calculated on the basis of the miRNA measurements.

<p>Receiver operating characteristic (ROC) curves are a widely accepted indicator of diagnostic utility. Measure of accuracy is the corresponding area under the ROC curve, denoted as AUC. It ranges in value from 0.5 (chance) to 1.0 (perfect discrimination).</p

Human PIK3R1 mutations disrupt lymphocyte differentiation to cause activated PI3Kδ syndrome 2.

Heterozygous loss-of-function (LOF) mutations in PIK3R1 (encoding phosphatidylinositol 3-kinase [PI3K] regulatory subunits) cause activated PI3Kδ syndrome 2 (APDS2), which has a similar clinical profile to APDS1, caused by heterozygous gain-of-function (GOF) mutations in PIK3CD (encoding the PI3K p110δ catalytic subunit). While several studies have established how PIK3CD GOF leads to immune dysregulation, less is known about how PIK3R1 LOF mutations alter cellular function. By studying a novel CRISPR/Cas9 mouse model and patients' immune cells, we determined how PIK3R1 LOF alters cellular function. We observed some overlap in cellular defects in APDS1 and APDS2, including decreased intrinsic B cell class switching and defective Tfh cell function. However, we also identified unique APDS2 phenotypes including defective expansion and affinity maturation of Pik3r1 LOF B cells following immunization, and decreased survival of Pik3r1 LOF pups. Further, we observed clear differences in the way Pik3r1 LOF and Pik3cd GOF altered signaling. Together these results demonstrate crucial differences between these two genetic etiologies