Health-Related Quality of Life in Patients with Subjective Cognitive Decline and Mild Cognitive Impairment and its Relation to Activities of Daily Living

BACKGROUND

Health related quality of life (HRQOL) is an important issue in the context of dementia care.

OBJECTIVES

The purpose of this study was to investigate HRQOL in patients with subjective cognitive decline (SCD) and mild cognitive impairment (MCI) and its relation to Activity of Daily Living (ADL).

METHODS

In this cross sectional study, four experimental groups (each n = 98), controls, SCD, naMCI and aMCI, were compared. For data collection, neuropsychological methods (NTBV) and psychological questionnaires (SF-36 and B-ADL) were used. Multivariate analysis of variance was calculated to detect differences in HRQOL between groups. Correlations between HRQOL and ADL were explored.

RESULTS

The dimensions of HRQOL showed mainly consistent differences between the control and the SCD group and MCI subgroups. In almost every dimension of HRQOL, the control group scored higher than subjects with SCD, naMCI, or aMCI. The controls showed low to moderate negative correlations between HQROL and B-ADL in some dimensions of the HRQOL. In the SCD group, low negative correlations with ADL were observed in some HRQOL scales. Low to moderate correlations were found between each scale of the SF-36 and the B-ADL in both MCI subtypes. We found gender differences in HRQOL.

CONCLUSION

In conclusion, we could demonstrate that patients with SCD report reduced quality of life. This knowledge is important to get a better understanding of the individuals with SCD and may pave the way for the development of early intervention.

Self-reported and informant-reported memory functioning and awareness in patients with mild cognitive impairment and Alzheimer´s disease

Background

Awareness of subjective memory is an important factor for adequate treatment of patients with mild cognitive impairment (MCI) and Alzheimer’s disease (AD). This study served to find out whether awareness of subjective memory complies with objective performance, if differences in awareness are observed longitudinally and whether decrease of awareness can serve as a predictor of AD in MCI patients.

Methods

Thirty-four patients with MCI seeking help in a memory outpatient clinic were included. All participants underwent thorough neuropsychological examination. Awareness of subjective memory was obtained by calculating difference scores between patient and informant ratings on a 16-item questionnaire concerning complaints about loss of memory in every-day life. Retesting was performed after a mean follow-up period of 24 months.

Results

Whole group analyses showed that awareness remained relatively stable across time. Self-reported memory complaints correlated with episodic memory at baseline and with performance on a language task at follow-up. Retests displayed decrease of awareness. At group level differences in awareness between both times of assessment were not significant for MCI and MCI patients converting to mild AD at follow-up. The predictive value of awareness was low.

Conclusions

Awareness of subjective memory deficit is linked to episodic memory function and decreases with decline of cognitive ability. Further studies evaluating predictive power of awareness of subjective memory should include a larger patient sample.

Production of Highly Polarized Positrons Using Polarized Electrons at MeV Energies

The Polarized Electrons for Polarized Positrons experiment at the injector of the Continuous Electron Beam Accelerator Facility has demonstrated for the first time the efficient transfer of polarization from electrons to positrons produced by the polarized bremsstrahlung radiation induced by a polarized electron beam in a high-Z target. Positron polarization up to 82% have been measured for an initial electron beam momentum of 8.19  MeV/c, limited only by the electron beam polarization. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community.

Antibiofilm activity of carboxymethyl chitosan on the biofilms of non-Candida albicans Candida species

Although most cases of candidiasis have been attributed to Candida albicans, non-C. albicans Candida species have been isolated in increasing numbers in patients. In this study, we determined the inhibition of carboxymethyl chitosan (CM-chitosan) on single and mixed species biofilm of non-albicans Candida species, including Candida tropicalis, Candida parapsilosis, Candida krusei and Candida glabrata. Biofilm by all tested species in microtiter plates were inhibited nearly 70%. CM-chitosan inhibited mixed species biofilm in microtiter plates and also on medical materials surfaces. To investigate the mechanism, the effect of CM-chitosan on cell viability and biofilm growth was employed. CM-chitosan inhibited Candida planktonic growth as well as adhesion. Further biofilm formation was inhibited with CM-chitosan added at 90min, 12h or 24h after biofilm initiation. CM-chitosan was not only able to inhibit the metabolic activity of Candida cells, but was also active upon the establishment and the development of biofilms.

A pressure and shear sensor system for stress measurement at lower limb residuum/socket interface

A sensor system for measurement of pressure and shear at the lower limb residuum/socket interface is described. The system comprises of a flexible sensor unit and a data acquisition unit with wireless data transmission capability. Static and dynamic performance of the sensor system was characterised using a mechanical test machine. The static calibration results suggest that the developed sensor system presents high linearity (linearity error ≤ 3.8%) and resolution (0.9 kPa for pressure and 0.2 kPa for shear). Dynamic characterisation of the sensor system shows hysteresis error of approximately 15% for pressure and 8% for shear. Subsequently, a pilot amputee walking test was conducted. Three sensors were placed at the residuum/socket interface of a knee disarticulation amputee and simultaneous measurements were obtained during pilot amputee walking test. The pressure and shear peak values as well as their temporal profiles are presented and discussed. In particular, peak pressure and shear of approximately 58 kPa and 27 kPa, respectively, were recorded. Their temporal profiles also provide dynamic coupling information at this critical residuum/socket interface. These preliminary amputee test results suggest strong potential of the developed sensor system for exploitation as an assistive technology to facilitate socket design, socket fit and effective monitoring of lower limb residuum health.

Subjective Memory Complaints and Conversion to Dementia in Patients with Subjective Cognitive Decline and Patients with Mild Cognitive Impairment

Abstract. Background: Subjective cognitive complaints and their clinical significance are discussed controversially. Objectives: To determine the clinical validity of subjective cognitive complaints among subjects with subjective cognitive decline (SCD) and mild cognitive impairment (MCI). Design: Longitudinal study with one follow up examination at a University based out-patient memory clinic. Participants: A clinical sample of patietns with SCD and MCI (n = 141), aged 50 and older, who came to the memory outpatient clinic. Results: No significant differences between converters and non converters regarding subjective cognitive complaints were detected. MCI patients had a higher risk than the patients with SCD developing AD (OR = 7.3 [CI 0.9 to 61.2]. Verbal memory testing using the Verbal Selektive Reminding Test (VSRT) showed better diagnostic validity than subjective cognitive complaints using the Forgetfulness Assessment Inventory (FAI) in predicting conversion to dementia. Conclusion: Verbal memory testing was superior in predicting conversion to dementia compared to subjective cognitive complaints.

Metastasis: Circulating Tumor Cells in Small Cell Lung Cancer

Small cell lung cancer (SCLC) is distinguished by excessive numbers of circulating tumor cells (CTCs) in extended and recurring disease. This malignancy has a poor prognosis due to rapid emergence of chemoradioresistant relapses after first-line chemotherapy. In vitro expansion of several CTC lines allowed for a detailed study of the contribution of these cells to metastasis. Generation of CTCs involves the establishment of co-cultures and recruitment of macrophages and specific cytokines. All cell lines show E-cadherin-positive epithelial-like cells and spontaneous assembling into very large tumorospheres. Such multicellular aggregates seem to be responsible for the observed broad resistance due to limited access to drugs, quiescent cell layers, and hypoxic cores.

Fitness differences between parapatric lake and stream stickleback revealed by a field transplant

Molecular comparisons of populations diverging into ecologically different environments often reveal strong differentiation in localized genomic regions, with the remainder of the genome being weakly differentiated. This pattern of heterogeneous genomic divergence, however, is rarely connected to direct measurements of fitness differences among populations. We here do so by performing a field enclosure experiment in threespine stickleback fish residing in a lake and in three replicate adjoining streams, and displaying weak yet heterogeneous genomic divergence between these habitats. Tracking survival over 29 weeks, we consistently find that lake genotypes transplanted into the streams suffer greatly reduced viability relative to local stream genotypes and that the performance of F1 hybrid genotypes is intermediate. This observed selection against migrants and hybrids combines to a total reduction in gene flow from the lake into streams of around 80%. Overall, our study identifies a strong reproductive barrier between parapatric stickleback populations, and cautions against inferring weak fitness differences between populations exhibiting weak overall genomic differentiation.

3D Printable Biophotopolymers for in Vivo Bone Regeneration

The present study investigated two novel biophotopolymer classes that are chemically based on non-toxic poly (vinyl alcohol). These vinylesters and vinylcarbonates were compared to standard acrylates in vitro on MC3T3-E1 cells and in vivo in a small animal model. In vitro, both vinylester and vinylcarbonate monomers showed about tenfold less cytotoxicity when compared to acrylates (IC₅₀: 2.922 mM and 2.392 mM vs. 0.201 mM) and at least threefold higher alkaline phosphatase activity (17.038 and 18.836 vs. 5.795, measured at [10 mM]). In vivo, polymerized 3D cellular structures were implanted into the distal femoral condyle of 16 New Zealand White Rabbits and were observed for periods from 4 to 12 weeks. New bone formation and bone to implant contact was evaluated by histomorphometry at end of observation. Vinylesters showed similar rates of new bone formation but significantly less (p = 0.002) bone to implant contact, when compared to acrylates. In contrast, the implantation of vinylcarbonate based biophotopolymers led to significantly higher rates of newly formed bone (p < 0.001) and bone to implant contact (p < 0.001). Additionally, distinct signs of polymer degradation could be observed in vinylesters and vinylcarbonates by histology. We conclude, that vinylesters and vinylcarbonates are promising new biophotopolymers, that outmatch available poly(lactic acid) and (meth)acrylate based materials.

Depressive Symptoms are the Main Predictor for Subjective Sleep Quality in Patients with Mild Cognitive Impairment--A Controlled Study

Objective

Controlled data on predictors of subjective sleep quality in patients with memory complaints are sparse. To improve the amount of comprehensive data on this topic, we assessed factors associated with subjective sleep quality in patients from our memory clinic and healthy individuals.

Methods

Between February 2012 and August 2014 patients with mild cognitive impairment (MCI) and subjective cognitive decline (SCD) from our memory clinic and healthy controls were recruited. Apart from a detailed neuropsychological assessment, the subjective sleep quality, daytime sleepiness and depressive symptoms were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Epworth Sleepiness Scale (ESS) and the Beck Depression Inventory (BDI-II).

Results

One hundred fifty eight consecutive patients (132 (84%) MCI patients and 26 (16%) SCD patients) and 75 healthy controls were included in the study. Pairwise comparison of PSQI scores showed that non-amnestic MCI (naMCI) patients (5.4±3.5) had significantly higher PSQI scores than controls (4.3±2.8, p = .003) Pairwise comparison of PSQI subscores showed that naMCI patients (1.1±0.4) had significantly more “sleep disturbances” than controls (0.9±0.5, p=.003). Amnestic MCI (aMCI) (0.8±1.2, p = .006) and naMCI patients (0.7±1.2, p = .002) used “sleep medication” significantly more often than controls (0.1±0.6) Both, aMCI (11.5±8.6, p<.001) and naMCI (11.5±8.6, p<.001) patients showed significantly higher BDI-II scores than healthy controls (6.1±5.3). Linear regression analysis showed that the subjective sleep quality was predicted by depressive symptoms in aMCI (p<.0001) and naMCI (p<.0001) patients as well as controls (p<.0001). This means, that more depressive symptoms worsened subjective sleep quality. In aMCI patients we also found a significant interaction between depressive symptoms and global cognitive function (p = .002)

Discussion

Depressive symptoms were the main predictor of subjective sleep quality in MCI patients and controls, but not in SCD patients. Better global cognitive function ameliorated the negative effect of depressive symptoms on the subjective sleep quality in aMCI patients.

Visuo-constructional functions in patients with mild cognitive impairment, Alzheimer's disease, and Parkinson's disease

BACKGROUND

Several recently proposed criteria for assessing cognitive disorder require measuring the cognitive domain of visuo-constructional function. The aims of the present study were to develop a new test (Vienna Visuo-constructional Test-VVT) measuring visuo-constructional functions and to determine the reliability and validity of the VVT in patients with mild cognitive impairment (MCI), Parkinson's disease (PD), and Alzheimer's disease (AD). We further examined age and sex effects and the psychometric quality of the VVT.

METHODS

The study included 76 healthy controls and 103 patients who were referred to the Department of Neurology, Medical University of Vienna for neurocognitive assessment. An administering and scoring system for the VVT was developed.

RESULTS

Internal consistency (Cronbach's alpha) was found to range from 0.82 for the healthy control group to 0.93 for the total patient group. There was no sex effect, but age had a negative effect on VVT performance. The VVT successfully differentiated healthy controls from MCI patients, AD patients, and PD patients, respectively.

CONCLUSION

The VVT shows satisfactory validity and reliability and can be administered easily in clinical practice. It constitutes a new measure that can successfully be used to identify visuo-constructional problems in patients with cognitive dysfunction.

Upregulation of osteoprotegerin expression correlates with bone invasion and predicts poor clinical outcome in oral cancer

OBJECTIVES

We aimed to determine the prognostic significance of receptor activator of nuclear factor kappa-B ligand (RANKL), RANK and osteoprotegerin (OPG) in patients with oral squamous cell carcinoma (OSCC).

MATERIALS AND METHODS

The protein expression of RANKL, RANK and OPG was assessed by immunohistochemistry on pretreatment biopsies of 93 patients with locally advanced OSCC who received preoperative chemoradiotherapy (CRT). The primary endpoint was cancer-specific survival. Secondary endpoints were correlation of biomarkers with bone invasion and pathological tumor response. Kaplan-Meier curves and Cox regression models were used for survival analyses.

RESULTS

A significantly higher OPG expression was demonstrated in patients with malignant bone invasion and non-responders to CRT as compared to patients without bone invasion and responders (p=0.032 and p=0.033, respectively). Multivariate analysis revealed that higher OPG expression was independently associated with shorter cancer-specific survival (p=0.04). The expression status of RANKL and RANK was not significantly related to clinicopathological characteristics and had no impact on survival of OSCC patients.

CONCLUSION

Upregulation of OPG expression is associated with bone invasion, poor pathological tumor regression to neoadjuvant CRT, and worse long-term cancer-specific survival in patients with locally advanced OSCC. Our results indicate that OPG may be a novel prognostic biomarker in oral cancer.

Development and validation of a 3D-printed interfacial stress sensor for prosthetic applications

A novel capacitance-based sensor designed for monitoring mechanical stresses at the stump-socket interface of lower-limb amputees is described. It provides practical means of measuring pressure and shear stresses simultaneously. In particular, it comprises of a flexible frame (20 mm × 20 mm), with thickness of 4mm. By employing rapid prototyping technology in its fabrication, it offers a low-cost and versatile solution, with capability of adopting bespoke shapes of lower-limb residua. The sensor was first analysed using finite element analysis (FEA) and then evaluated using lab-based electromechanical tests. The results validate that the sensor is capable of monitoring both pressure and shear at stresses up to 350 kPa and 80 kPa, respectively. A post-signal processing model is developed to induce pressure and shear stresses, respectively. The effective separation of pressure and shear signals can be potentially advantageous for sensor calibration in clinical applications. The sensor also demonstrates high linearity (approx. 5-8%) and high pressure (approx. 1.3 kPa) and shear (approx. 0.6 kPa) stress resolution performance. Accordingly, the sensor offers the potential for exploitation as an assistive tool to both evaluate prosthetic socket fitting in clinical settings and alert amputees in home settings of excessive loading at the stump-socket interface, effectively preventing stump tissue breakdown at an early stage.

Subjective memory complaints, depressive symptoms and cognition in Parkinson's disease patients

BACKGROUND AND PURPOSE

The goal of this study was to establish the prevalence of subjective memory complaints (SMCs) and depressive symptoms (DS)s and their relation to cognitive functioning in patients with Parkinson's disease (PD).

METHODS

In all, 248 controls and 104 PD patients were included in the study. The PD group was subdivided into three PD subtypes with mild cognitive impairment (MCI) according to the Petersen criteria and three PD subtypes with MCI according to the Litvan criteria.

RESULTS

Substantial SMCs were reported by 7.7% of controls and 16.3% of the PD patients (P < 0.001). A clinically relevant degree of DSs was evident in 16.6% of controls compared with 40.4% in the PD group (P < 0.001). An analysis of variance revealed a statistically significant difference for SMCs across all Petersen groups as well across all Litvan groups. Two-factor analyses of variance with the factors cognitive status (MCI subtype) and depressive state (depressed versus not depressed) and SMCs as dependent variable revealed significant results.

CONCLUSIONS

Approximately 15% of PD patients seeking help in a movement disorder clinic report significant SMCs, with an increasing degree from cognitively healthy PD to PD-MCI. Significant DSs increase SMCs across all cognitive status groups.

Prevalence of Mild Cognitive Impairment Subtypes in Patients with Parkinson’s Disease – Comparison of two Modes of Classification

Early detection of dementia in Parkinson’s disease is becoming increasingly important. The goal of this study was to establish prevalence of mild cognitive impairment subtypes in Parkinson’s disease using two different modes of mild cognitive impairment classification. Categorizing patients into mild cognitive impairment subtypes according to the minimum mode of mild cognitive impairment classification revealed the following results: three patients (2.5 %) were categorized as cognitively healthy, whereas 117 patients (97.5 %) met the criteria for mild cognitive impairment. When categorizing patients according to the mean mode of mild cognitive impairment classification, 41.7 % of the patients were categorized as cognitively healthy, whereas 58.3 % met the criteria for mild cognitive impairment. Frequency of mild cognitive impairment varies substantially, depending on how impairment is defined.

Acute caffeine administration impact on working memory-related brain activation and functional connectivity in the elderly: a BOLD and perfusion MRI study

In young individuals, caffeine-mediated blockade of adenosine receptors and vasoconstriction has direct repercussions on task-related activations, changes in functional connectivity, as well as global vascular effects. To date, no study has explored the effect of caffeine on brain activation patterns during highly demanding cognitive tasks in the elderly. This prospective, placebo-controlled crossover design comprises 24 healthy elderly individuals (mean age 68.8 ± 4.0 years, 17 females) performing a 2-back working memory (WM) task in functional magnetic resonance imaging (fMRI). Analyses include complimentary assessment of task-related activations (general linear model, GLM), functional connectivity (tensorial independent component analysis, TICA), and baseline perfusion (arterial spin labeling). Despite a reduction in whole-brain global perfusion (-22.7%), caffeine-enhanced task-related GLM activation in a local and distributed network is most pronounced in the bilateral striatum and to a lesser degree in the right middle and inferior frontal gyrus, bilateral insula, left superior and inferior parietal lobule as well as in the cerebellum bilaterally. TICA was significantly enhanced (+8.2%) in caffeine versus placebo in a distributed and task-relevant network including the pre-frontal cortex, the supplementary motor area, the ventral premotor cortex and the parietal cortex as well as the occipital cortex (visual stimuli) and basal ganglia. The inverse comparison of placebo versus caffeine had no significant difference. Activation strength of the task-relevant-network component correlated with response accuracy for caffeine yet not for placebo, indicating a selective cognitive effect of caffeine. The present findings suggest that acute caffeine intake enhances WM-related brain activation as well as functional connectivity of blood oxygen level-dependent fMRI in elderly individuals.

Is reoperation an option for patients with temporal lobe epilepsy after failure of surgery?

PURPOSE

Epilepsy surgery is the most efficacious therapeutic modality for patients with medically refractory focal epilepsies, but surgical failures remain a challenge to the epilepsy treatment team. The aim of present study was to evaluate the postoperative outcome of patients who underwent reoperation after a failed epilepsy surgery on the temporal lobe.

METHODS

We systematically analyzed the results of comprehensive preoperative evaluations before the first surgery, and before and after reoperation in 17 patients with drug resistant temporal lobe epilepsies.

RESULTS

Overall, 13 of 17 patients (76.5%) improved after reoperation: five patients (29.4%) were completely seizure free after reoperation (median duration 60months, range 12-72); six patients (35.3%) were seizure free at least 12month before observation points (median duration 120.5months, range 35-155) and two patients (11.8%) had a decrease in seizure frequency. Four patients (23.5%) remained unchanged with respect to seizure frequency and severity. There was no correlation between the improvement in seizure outcome after reoperation and other clinical data except of the history of traumatic brain injury (TBI). The patients who had no history of TBI improved after reoperation, compared to patients with TBI (p=0.044). The postoperative seizure outcome of patients with incongruent Video-EEG results before the first surgery (p=0.116) and before reoperation (p=0.622) was not poorer compared to patients with congruent Video-EEG results.

CONCLUSIONS

Reoperation can considerably improve the operative outcome of the first failed epilepsy surgery in patients with drug resistant temporal lobe epilepsies. Epilepsy centres should be encouraged to report the results of failed epilepsy surgeries.

Mobile hydrocarbon microspheres from >2-billion-year-old carbon-bearing seams in the South African deep subsurface

By ~2.9 Ga, the time of the deposition of the Witwatersrand Supergroup, life is believed to have been well established on Earth. Carbon remnants of the microbial biosphere from this time period are evident in sediments from around the world. In the Witwatersrand Supergroup, the carbonaceous material is often concentrated in seams, closely associated with the gold deposits and may have been a mobile phase 2 billion years ago. Whereas today the carbon in the Witwatersrand Supergroup is presumed to be immobile, hollow hydrocarbon spheres ranging in size from <1 μm to >50 μm were discovered emanating from a borehole drilled through the carbon-bearing seams suggesting that a portion of the carbon may still be mobile in the deep subsurface. ToF-SIMS and STXM analyses revealed that these spheres contain a suite of alkane, alkenes, and aromatic compounds consistent with the described organic-rich carbon seams within the Witwatersrand Supergroup's auriferous reef horizons. Analysis by electron microscopy and ToF-SIMS, however, revealed that these spheres, although most likely composed of biogenic carbon and resembling biological organisms, do not retain any true structural, that is, fossil, information and were formed by an abiogenic process.