223 research outputs found
Resting state correlates of subdimensions of anxious affect
Resting state fMRI may help identify markers of risk for affective disorder. Given the comorbidity of anxiety and depressive disorders and the heterogeneity of these disorders as defined by DSM, an important challenge is to identify alterations in resting state brain connectivity uniquely associated with distinct profiles of negative affect. The current study aimed to address this by identifying differences in brain connectivity specifically linked to cognitive and physiological profiles of anxiety, controlling for depressed affect. We adopted a two-stage multivariate approach. Hierarchical clustering was used to independently identify dimensions of negative affective style and resting state brain networks. Combining the clustering results, we examined individual differences in resting state connectivity uniquely associated with subdimensions of anxious affect, controlling for depressed affect. Physiological and cognitive subdimensions of anxious affect were identified. Physiological anxiety was associated with widespread alterations in insula connectivity, including decreased connectivity between insula subregions and between the insula and other medial frontal and subcortical networks. This is consistent with the insula facilitating communication between medial frontal and subcortical regions to enable control of physiological affective states. Meanwhile, increased connectivity within a frontoparietal-posterior cingulate cortex-precunous network was specifically associated with cognitive anxiety, potentially reflecting increased spontaneous negative cognition (e.g., worry). These findings suggest that physiological and cognitive anxiety comprise subdimensions of anxiety-related affect and reveal associated alterations in brain connectivity
Does the Maximum in the Zeta Potential of Monodisperse Polystyrene Particles Really Exist? An Electrokinetic Study
The zeta potential of monodisperse polystyrene latices as a function of ionic strength is usually reported to display a maximum. In this paper it iis shown that this is either due to artefacts in measuring streaming currents and electrical conductances of plugs, or to the anomalous surface conductance inherent to these systems not being accounted for in the theories relating electrophoretic mobilities to zeta potential
Evaluating functional brain organization in individuals and identifying contributions to network overlap
Individual differences in the spatial organization of resting-state networks have received increased attention in recent years. Measures of individual-specific spatial organization of brain networks and overlapping network organization have been linked to important behavioral and clinical traits and are therefore potential biomarker targets for personalized psychiatry approaches. To better understand individual-specific spatial brain organization, this paper addressed three key goals. First, we determined whether it is possible to reliably estimate weighted (non-binarized) resting-state network maps using data from only a single individual, while also maintaining maximum spatial correspondence across individuals. Second, we determined the degree of spatial overlap between distinct networks, using test-retest and twin data. Third, we systematically tested multiple hypotheses (spatial mixing, temporal switching, and coupling) as candidate explanations for why networks overlap spatially. To estimate weighted network organization, we adopt the Probabilistic Functional Modes (PROFUMO) algorithm, which implements a Bayesian framework with hemodynamic and connectivity priors to supplement optimization for spatial sparsity/independence. Our findings showed that replicable individual-specific estimates of weighted resting-state networks can be derived using high-quality fMRI data within individual subjects. Network organization estimates using only data from each individual subject closely resembled group-informed network estimates (which was not explicitly modeled in our individual-specific analyses), suggesting that cross-subject correspondence was largely maintained. Furthermore, our results confirmed the presence of spatial overlap in network organization, which was replicable across sessions within individuals and in monozygotic twin pairs. Intriguingly, our findings provide evidence that overlap between 2-network pairs is indicative of coupling. These results suggest that regions of network overlap concurrently process information from both contributing networks, potentially pointing to the role of overlapping network organization in the integration of information across multiple brain systems
Association between Several Clinical and Radiological Determinants with Long-Term Clinical Progression and Good Prognosis of Lower Limb Osteoarthritis
Abstract Objective: To investigate the factors associated with clinical progression and good prognosis in patients with lower limb osteoarthritis (OA). Methods: Cohort study of 145 patients with OA in either knee, hip or both. Progression was defined as 1) new joint prosthesis or 2) increase in WOMAC pain or function score during 6-years follow-up above pre-defined thresholds. Patients without progression with decrease in WOMAC pain or function score lower than pre-defined thresholds were categorized as good prognosis. Relative risks (RRs) for progression and good prognosis with 95% confidence interval (95% CI) were calculated by comparing the highest tertile or category to the lowest tertile, for baseline determinants (age, sex, BMI, WOMAC pain and function scores, pain on physical examination, total range of motion (tROM), osteophytes and joint space narrowing (JSN) scores), and for worsening in WOMAC pain and function score in 1-year. Adjustments were performed for age, sex, and BMI. Results: Follow-up was completed by 117 patients (81%, median age 60 years, 84% female); 62 (53%) and 31 patients (26%) showed progression and good prognosis, respectively. These following determinants were associated with progression: pain on physical examination (RR 1.2 (1.0 to 1.5)); tROM (1.4 (1.1 to 1.6); worsening in WOMAC pain (1.9 (1.2 to 2.3)); worsening in WOMAC function (2.4 (1.7 to 2.6)); osteophytes 1.5 (1.0 to 1.8); and JSN scores (2.3 (1.5 to 2.7)). Worsening in WOMAC pain (0.1 (0.1 to 0.8)) and function score (0.1 (0.1 to 0.7)), were negatively associated with good prognosis. Conclusion: Worsening of self-reported pain and function in one year, limited tROM and higher osteophytes and JSN scores were associated with clinical progression. Worsening in WOMAC pain and function score in 1-year were associated with lower risk to have good prognosis. These findings help to inform patients with regard to their OA prognosis
Window of opportunity in psoriatic arthritis:The earlier the better?
Objectives To investigate whether there is a window of opportunity for psoriatic arthritis (PsA) patients and to assess which patient characteristics are associated with a longer diagnostic delay. Methods All newly diagnosed, disease-modifying antirheumatic drug-naïve PsA patients who participated in the Dutch southwest Early PsA cohoRt and had ≥3 years of follow-up were studied. First, total delay was calculated as the time period between symptom onset and PsA diagnosis made by a rheumatologist and then split into patient and physician delays. The total delay was categorised into short (<12 weeks), intermediate (12 weeks to 1 year) or long (>1 year). These groups were compared on clinical (Minimal Disease Activity (MDA) and Disease Activity index for PSoriatic Arthritis (DAPSA) remission) and patient-reported outcomes during 3 years follow-up. Results 708 PsA patients were studied of whom 136 (19%), 237 (33%) and 335 (47%) had a short, intermediate and long total delay, respectively. Patient delay was 1.0 month and physician delay was 4.5 months. Patients with a short delay were more likely to achieve MDA (OR 2.55, p=0.003) and DAPSA remission (OR 2.35,p=0.004) compared with PsA patients with a long delay. Patient-reported outcomes showed numerical but non-significant differences between the short and long delay groups. Female patients and those presenting with enthesitis, chronic back pain or normal C-reactive protein (CRP) had a longer delay. Conclusions In PsA, referral and diagnosis within 1 year is associated with better clinical outcomes, suggesting the presence of a window of opportunity. The most gain in referral could be obtained in physician delay and in females, patients with enthesitis, chronic back pain or normal CRP.</p
Window of opportunity in psoriatic arthritis:The earlier the better?
Objectives To investigate whether there is a window of opportunity for psoriatic arthritis (PsA) patients and to assess which patient characteristics are associated with a longer diagnostic delay. Methods All newly diagnosed, disease-modifying antirheumatic drug-naïve PsA patients who participated in the Dutch southwest Early PsA cohoRt and had ≥3 years of follow-up were studied. First, total delay was calculated as the time period between symptom onset and PsA diagnosis made by a rheumatologist and then split into patient and physician delays. The total delay was categorised into short (<12 weeks), intermediate (12 weeks to 1 year) or long (>1 year). These groups were compared on clinical (Minimal Disease Activity (MDA) and Disease Activity index for PSoriatic Arthritis (DAPSA) remission) and patient-reported outcomes during 3 years follow-up. Results 708 PsA patients were studied of whom 136 (19%), 237 (33%) and 335 (47%) had a short, intermediate and long total delay, respectively. Patient delay was 1.0 month and physician delay was 4.5 months. Patients with a short delay were more likely to achieve MDA (OR 2.55, p=0.003) and DAPSA remission (OR 2.35,p=0.004) compared with PsA patients with a long delay. Patient-reported outcomes showed numerical but non-significant differences between the short and long delay groups. Female patients and those presenting with enthesitis, chronic back pain or normal C-reactive protein (CRP) had a longer delay. Conclusions In PsA, referral and diagnosis within 1 year is associated with better clinical outcomes, suggesting the presence of a window of opportunity. The most gain in referral could be obtained in physician delay and in females, patients with enthesitis, chronic back pain or normal CRP.</p
Potential therapeutic effects of branched-chain amino acids supplementation on resistance exercise-based muscle damage in humans
Branched-chain amino acids (BCAA) supplementation has been considered an interesting nutritional strategy to improve skeletal muscle protein turnover in several conditions. In this context, there is evidence that resistance exercise (RE)-derived biochemical markers of muscle soreness (creatine kinase (CK), aldolase, myoglobin), soreness, and functional strength may be modulated by BCAA supplementation in order to favor of muscle adaptation. However, few studies have investigated such effects in well-controlled conditions in humans. Therefore, the aim of this short report is to describe the potential therapeutic effects of BCAA supplementation on RE-based muscle damage in humans. The main point is that BCAA supplementation may decrease some biochemical markers related with muscle soreness but this does not necessarily reflect on muscle functionality
Comparative Therapeutic Effects of Velaglucerase Alfa and Imiglucerase in a Gaucher Disease Mouse Model
Gaucher disease type 1 is caused by the defective activity of the lysosomal enzyme, acid β-glucosidase (GCase). Regular infusions of purified recombinant GCase are the standard of care for reversing hematologic, hepatic, splenic, and bony manifestations. Here, similar in vitro enzymatic properties, and in vivo pharmacokinetics and pharmacodynamics (PK/PD) and therapeutic efficacy of GCase were found with two human GCases, recombinant GCase (CHO cell, imiglucerase, Imig) and gene-activated GCase (human fibrosarcoma cells, velaglucerase alfa, Vela), in a Gaucher mouse, D409V/null. About 80+% of either enzyme localized to the liver interstitial cells and <5% was recovered in spleens and lungs after bolus i.v. injections. Glucosylceramide (GC) levels and storage cell numbers were reduced in a dose (5, 15 or 60 U/kg/wk) dependent manner in livers (60–95%) and in spleens (∼10–30%). Compared to Vela, Imig (60 U/kg/wk) had lesser effects at reducing hepatic GC (p = 0.0199) by 4 wks; this difference disappeared by 8 wks when nearly WT levels were achieved by Imig. Anti-GCase IgG was detected in GCase treated mice at 60 U/kg/wk, and IgE mediated acute hypersensitivity and death occurred after several injections of 60 U/kg/wk (21% with Vela and 34% with Imig). The responses of GC levels and storage cell numbers in Vela- and Imig-treated Gaucher mice at various doses provide a backdrop for clinical applications and decisions
Mechanisms and role of microRNA deregulation in cancer onset and progression
MicroRNAs are key regulators of various fundamental biological processes and, although representing only a small portion of the genome, they regulate a much larger population of target genes. Mature microRNAs (miRNAs) are single-stranded RNA molecules of 20–23 nucleotide (nt) length that control gene expression in many cellular processes. These molecules typically reduce the stability of mRNAs, including those of genes that mediate processes in tumorigenesis, such as inflammation, cell cycle regulation, stress response, differentiation, apoptosis and invasion. MicroRNA targeting is mostly achieved through specific base-pairing interactions between the 5′ end (‘seed’ region) of the miRNA and sites within coding and untranslated regions (UTRs) of mRNAs; target sites in the 3′ UTR diminish mRNA stability. Since miRNAs frequently target hundreds of mRNAs, miRNA regulatory pathways are complex. Calin and Croce were the first to demonstrate a connection between microRNAs and increased risk of developing cancer, and meanwhile the role of microRNAs in carcinogenesis has definitively been evidenced. It needs to be considered that the complex mechanism of gene regulation by microRNAs is profoundly influenced by variation in gene sequence (polymorphisms) of the target sites. Thus, individual variability could cause patients to present differential risks regarding several diseases. Aiming to provide a critical overview of miRNA dysregulation in cancer, this article reviews the growing number of studies that have shown the importance of these small molecules and how these microRNAs can affect or be affected by genetic and epigenetic mechanisms
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