20 research outputs found
Insights into the morphology of multicomponent organic and inorganic aerosols from molecular dynamics simulations
We explore the
morphologies of multicomponent nanoparticles through atomistic molecular
dynamics simulations under atmospherically relevant conditions. The particles
investigated consist of both organic (cis-pinonic acid – CPA,
3-methyl-1,2,3-butanetricarboxylic acid – MBTCA,
n-C20H42, n-C24H50,
n-C30H62 or mixtures thereof) and inorganic (sulfate,
ammonium and water) compounds. The effects of relative humidity, organic mass
content and type of organic compound present in the nanoparticle are
investigated. Phase separation is predicted for almost all simulated
nanoparticles either between organics and inorganics or between hydrophobic
and hydrophilic constituents. For oxygenated organics, our simulations
predict an enrichment of the nanoparticle surface in organics, often in the
form of islands depending on the level of humidity and organic mass fraction,
giving rise to core–shell structures. In several cases the organics separate
from the inorganics, especially from the ions. For particles containing
water-insoluble linear alkanes, separate hydrophobic and hydrophilic domains
are predicted to develop. The surface partitioning of organics is enhanced as
the humidity increases. The presence of organics in the interior of the
nanoparticle increases as their overall mass fraction in the nanoparticle
increases, but this also depends on the humidity conditions. Apart from the
organics–inorganics and hydrophobics–hydrophilics separation, our
simulations predict a third type of separation (layering) between CPA and
MBTCA molecules under certain conditions.</p
Spastic paraplegia preceding PSEN1-related familial Alzheimer's disease.
Introduction: We investigated the frequency, neuropathology, and phenotypic characteristics of spastic paraplegia (SP) that precedes dementia in presenilin 1 (PSEN1) related familial Alzheimer's disease (AD). Methods: We performed whole exome sequencing (WES) in 60 probands with hereditary spastic paraplegia (HSP) phenotype that was negative for variants in known HSP-related genes. Where PSEN1 mutation was identified, brain biopsy was performed. We investigated the link between HSP and AD with PSEN1 in silico pathway analysis and measured in vivo the stability of PSEN1 mutant γ-secretase. Results: We identified a PSEN1 variant (p.Thr291Pro) in an individual presenting with pure SP at 30 years of age. Three years later, SP was associated with severe, fast cognitive decline and amyloid deposition with diffuse cortical plaques on brain biopsy. Biochemical analysis of p.Thr291Pro PSEN1 revealed that although the mutation does not alter active γ-secretase reconstitution, it destabilizes γ-secretase-amyloid precursor protein (APP)/amyloid beta (Aβn) interactions during proteolysis, enhancing the production of longer Aβ peptides. We then extended our analysis to all 226 PSEN1 pathogenic variants reported and show that 7.5% were associated with pure SP onset followed by cognitive decline later in the disease. We found that PSEN1 cases manifesting initially as SP have a later age of onset, are associated with mutations located beyond codon 200, and showed larger diffuse, cored plaques, amyloid-ring arteries, and severe CAA. Discussion: We show that pure SP can precede dementia onset in PSEN1-related familial AD. We recommend PSEN1 genetic testing in patients presenting with SP with no variants in known HSP-related genes, particularly when associated with a family history of cognitive decline
Potential users of visual prosthesis: expectations, motivation and attitudes towards participation
965Experimental animal model for the study of bladder wall regeneration using a peritoneum plus vicryl mesh patch
Association of 5-HTTLPR Polymorphism with the Nursing Diagnoses and the Achievement of Nursing Outcomes in Patients with Major Depression
The aim of this study is to investigate whether a 44-base-pair insertion/deletion polymorphism in the upstream regulatory region of the serotonin transporter gene (5-HTTLPR) is associated with the nursing diagnoses and the achievement of the desired nursing outcomes in inpatients with major depression. Thirty five patients were evaluated. The nursing diagnoses of risk for suicide and imbalanced nutrition are reported less often in homozygotes of the high-expressing gene (LA). Carriers of the low-expressing genes (LG or S) have a worse response to interventions which aim to increase low self-esteem, indicating that they may need more intensive care in order to achieve the desired outcome. Genetics in psychiatric nursing could help refine personalized care, however further studies with large sample sizes and multiple gene evaluations are needed. © 2017 Taylor & Francis Group, LLC
Replication study of GWAS risk loci in Greek multiple sclerosis patients
Objectives: To validate in an ethnically homogeneous Greek multiple sclerosis (MS) cohort, genetic risk factors for the disease, identified through a number of previous multi-ethnic genome-wide association studies (GWAS). Methods: A total of 1228 MS cases and 1014 controls were recruited in the study, from 3 MS centers in Greece. We genotyped 35 susceptibility SNPs that emerged from previous GWAS or meta-analyses of GWAS. Allele and genotype single locus regression analysis, adjusted for gender and site, was performed. Permutation testing was applied to all analyses. Results: Six polymorphisms reached statistical significance (permutation p value < 0.05). In particular, rs2760524 of LOC105371664, near RGS1 (permutation p value 0.001), rs3129889 of HLA-DRA, near HLA-DRB1 (permutation p value < 1.00e-04), rs1738074 of TAGAP (permutation p value 0.007), rs703842 of METTL1/CYP27B1 (permutation p value 0.008), rs9596270 of DLEU1 (permutation p value < 1.00e-04), and rs17445836 of LincRNA, near IRF8 (permutation p value 0.001) were identified as susceptibility risk factors in our group. Conclusion: The current study replicated a number of GWAS susceptibility SNPs, which implies that some similarities between the examined Greek population and the MS genetic architecture of the GWAS populations do exist. © 2018, Springer-Verlag Italia S.r.l., part of Springer Nature
Efficacy of tropisetron in patients with advanced non-small-cell lung cancer receiving adjuvant chemotherapy with carboplatin and taxanes
Even though significant progress has been made, chemotherapy-induced emesis remains a challenging problem. Few studies focus on emesis in patients treated with carboplatin and the observation period is limited to the initial 24 h following chemotherapy. Thus, we investigated if tropisetron (T) monotherapy can adequately prevent acute and delayed emesis in non-small-cell lung cancer (NSCLC) patients receiving a moderately emetogenic chemotherapy (MEC) (carboplatin-containing) regimen. Furthermore, we explored the merits of adding dexamethasone (D) or alprazolam (A) to T, especially in the setting of a pre-existing high level of stress. We studied 60 patients with advanced NSCLC receiving carboplatin and taxanes in three consecutive cycles. During the first cycle, patients received 5 mg of T intravenously before chemotherapy and the same dose per os on each of the following 3 days. In the second cycle, T was co-administered with 8 mg of D once a day, while, during the third cycle, T was combined with per os A 0.25 mg every 12 h and continued over the following 3 days. Finally, we evaluated the impact of stress on the anti-emetic response achieved with the previously described regimens. The combination of T + A was superior to T monotherapy and the combination of T + D, regarding the prevention of acute and delayed emesis. Both T + A and T + D combinations led to appetite improvement, while patients receiving T + A experienced sedation more frequently. Interestingly, subgroup analysis revealed that patients without underlying stress obtained no further benefit by the addition of A or D, while both T + A and T + D combinations led to a better anti-emetic response in patients with stress. In conclusion, T monotherapy provides a satisfactory result in controlling nausea and emesis caused by a MEC regimen in patients without stress. However, the addition of D and, mainly, A improves its anti-emetic effect in patients with obvious stress. © 2007 Blackwell Publishing Ltd
Genotyping and plasma/cerebrospinal fluid profiling of a cohort of frontotemporal dementia–amyotrophic lateral sclerosis patients
Frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS) are part of the same pathophysiological spectrum and have common genetic and cerebrospinal fluid (CSF) biomarkers. Our aim here was to identify causative gene variants in a cohort of Greek patients with FTD, ALS and FTD-ALS, to measure levels of CSF biomarkers and to investigate genotype-phenotype/CSF biomarker associations. In this cohort of 130 patients (56 FTD, 58 ALS and 16 FTD-ALS), we performed C9orf72 hexanucleotide repeat expansion analysis, whole exome sequencing and measurement of “classical” (Aβ42, total tau and phospho-tau) and novel (TDP-43) CSF biomarkers and plasma progranulin. Through these analyses, we identified 14 patients with C9orf72 repeat expansion and 11 patients with causative variants in other genes (three in TARDBP, three in GRN, three in VCP, one in FUS, one in SOD1). In ALS patients, we found that levels of phospho-tau were lower in C9orf72 repeat expansion and MAPT c.855C&gt;T (p.Asp285Asp) carriers compared to non-carriers. Additionally, carriers of rare C9orf72 and APP variants had lower levels of total tau and Aβ42, respectively. Plasma progranulin levels were decreased in patients carrying GRN pathogenic variants. This study expands the genotypic and phenotypic spectrum of FTD/ALS and offers insights in possible genotypic/CSF biomarker associations. © 2021 by the authors. Licensee MDPI, Basel, Switzerland
Genetic association between the phospholipase A2 gene and unipolar affective disorder: a multicentre case-control study.
The co-segregation in one pedigree of bipolar affective disorder with Darier's disease whose gene is on chromosome 12q23-q24.1, and findings from linkage and association studies with the neighbouring gene of phospholipase A2 (PLA2) indicate that PLA2 may be considered as a candidate gene for affective disorders. All relevant genetic association studies, however, were conducted on bipolar patients. In the present study, the possible association between the PLA2 gene and unipolar affective disorder was examined on 321 unipolar patients and 604 controls (all personally interviewed), recruited from six countries (Belgium, Bulgaria, Croatia, Germany, Greece, and Italy) participating in the European Collaborative Project on Affective Disorders. After controlling for population group and gender, one of the eight alleles of the investigated marker (allele 7) was found to be more frequent among unipolar patients with more than three major depressive episodes than among controls (P<0.01); genotypic association was also observed, under the dominant model of genetic transmission (P<0.02). In addition, presence of allele 7 was correlated with a higher frequency of depressive episodes (P<0.02). These findings suggest that structural variations at the PLA2 gene or the chromosomal region around it may confer susceptibility for unipolar affective disorder.Journal ArticleMulticenter StudyResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe