Hippocampal and motor regions contribute to memory benefits after enacted encoding: cross-sectional and longitudinal evidence.

The neurobiological underpinnings of action-related episodic memory and how enactment contributes to efficient memory encoding are not well understood. We examine whether individual differences in level (n = 338) and 5-year change (n = 248) in the ability to benefit from motor involvement during memory encoding are related to gray matter (GM) volume, white matter (WM) integrity, and dopamine-regulating genes in a population-based cohort (age range = 25-80 years). A latent profile analysis identified 2 groups with similar performance on verbal encoding but with marked differences in the ability to benefit from motor involvement during memory encoding. Impaired ability to benefit from enactment was paired with smaller HC, parahippocampal, and putamen volume along with lower WM microstructure in the fornix. Individuals with reduced ability to benefit from encoding enactment over 5 years were characterized by reduced HC and motor cortex GM volume along with reduced WM microstructure in several WM tracts. Moreover, the proportion of catechol-O-methyltransferase-Val-carriers differed significantly between classes identified from the latent-profile analysis. These results provide converging evidence that individuals with low or declining ability to benefit from motor involvement during memory encoding are characterized by low and reduced GM volume in regions critical for memory and motor functions along with altered WM microstructure.

Which intellectual activities are related to cognitive reserve? Introduction and testing a three-dimensional model.

BACKGROUND: A common belief among people and some researchers is that keeping yourself mentally active may decrease the risk of dementia. Over the past years, despite widespread efforts to identify proxies for protecting cognitive reserve against age-related changes, it is still not clear what type of intellectual activity would be beneficial for cognitive reserve. To fill this gap, we propose a three-dimensional model of intellectual activity. According to this conceptual model, intellectual activities could be distinguished based on their locations in a three-dimensions space, including; (1) Activation: active vs. passive, (2) Novelty: novel vs. familiar, and (3) Productivity: productive vs. receptive. We assumed that the activities that are categorized as more active, novel, and productive could be considered as a cognitive reserve proxy. METHODS: To test this hypothesis, a sample of 237 participants older than 50 years (Mage = 58.76 ± 6.66; 63.7% women) was recruited to take part in the study. Episodic, semantic and working memory were assessed with computerized battery tests (Sepidar) and a self-report questionnaire was used to assess intellectual activities. Activities were categorized in terms of; (1) passive, familiar, and receptive activities (radio/watching TV), (2) active, familiar, and receptive activities (solving crosswords), (3) active, novel, and receptive activities (reading), and (4) active, novel, and productive activities (writing). RESULTS: The results indicated that writing moderates the effect of age on episodic and semantic memory. Reading only moderates the effect of age on semantic memory, and radio/watching TV and solving crosswords do not play a role in moderation analysis. CONCLUSIONS: Our finding suggests that intellectual activities have different moderating effects on the relationships between age and memory performance. Individuals with high levels of participation in novel and productive activities over the life course are less likely to clinically demonstrate cognitive impairments. Our results support the potential benefit of the three-dimensional model to provide a better insight into the complex role of intellectual activities in cognitive reserve, particularly for older adults. Further research is needed to evaluate the efficacy and the benefits of the model.

Digital CRISPR Systems for the Next Generation of Nucleic Acid Quantification.

Digital CRISPR (dCRISPR) assays are an emerging platform of molecular diagnostics. Digital platforms introduce absolute quantification and increased sensitivity to bulk CRISPR assays. With ultra-specific targeting, isothermal operation, and rapid detection, dCRISPR systems are well-prepared to lead the field of molecular diagnostics. Here we summarized the common Cas proteins used in CRISPR detection assays. The methods of digital detection and critical performance factors are examined. We formed three strategies to frame the landscape of dCRISPR systems: (1) amplification free, (2) in-partition amplification, and (3) two-stage amplification. We also compared the performance of all systems through the limit of detection (LOD), testing time, and figure of merit (FOM). This work summarizes the details of digital CRISPR platforms to guide future development. We envision that improvements to LOD and dynamic range will position dCRISPR as the leading platform for the next generation of molecular biosensing.

Detection of SARS-CoV-2 with Solid-State CRISPR-Cas12a-Assisted Nanopores.

The outbreak of the SARS-CoV-2 caused the disease COVID-19 to spread globally. Specific and sensitive detection of SARS-CoV-2 facilitates early intervention and prevents the disease from spreading. Here, we present a solid-state CRISPR-Cas12a-assisted nanopore (SCAN) sensing strategy for the specific detection of SARS-CoV-2. We introduced a nanopore-sized counting method to measure the cleavage ratio of reporters, which is used as a criterion for positive/negative classification. A kinetic cleavage model was developed and validated to predict the reporter size distributions. The model revealed the trade-offs between sensitivity, turnaround time, and false-positive rate of the SARS-CoV-2 SCAN. With preamplification and a 30 min CRISPR Cas12a assay, we achieved excellent specificity against other common human coronaviruses and a limit of detection of 13.5 copies/µL (22.5 aM) of viral RNA at a confidence level of 95%. These results suggested that the SCAN could provide a rapid, sensitive, and specific analysis of SARS-CoV-2.

Nanofluidic charged-coupled devices for controlled DNA transport and separation.

Controlled molecular transport and separation is of significant importance in various applications. In this work, we presented a novel concept of nanofluidic molecular charge-coupled device (CCD) for controlled DNA transport and separation. By leveraging the unique field-effect coupling in nanofluidic systems, the nanofluidic molecular CCD aims to store charged biomolecules such as DNAs in discrete regions in nanochannels and transfer and separate these biomolecules as a charge packet in a bucket brigade fashion. We developed a quantitative model to capture the impact of nanochannel surface charge, gating voltage and frequency, molecule diffusivity, and gating electrode geometry on the transport and separation efficiency. We studied the synergistic effects of these factors to guide the device design and optimize the DNA transport and separation in a nanofluidic CCD. The findings in this study provided insight into the rational design and implementation of the nanofluidic molecular CCD.

The effects of different proxies of cognitive reserve on episodic memory performance: aging study in Iran.

OBJECTIVE: The main aim of the present study is to investigate the association between different measures of cognitive reserve including bilingualism, mental activities, type of education (continuous versus distributed), age, educational level, and episodic memory in a healthy aging sample. METHODS: Four hundred and fifteen participants aged between 50 and 83 years participated in this cross-sectional study and were assessed with the Psychology Experimental Building Language Test battery tapping episodic memory. Demographic variables were collected from a questionnaire designed by the research team. RESULTS: Compared to participants with continuous type of education, those with distributed type performed better in tests of episodic memory, while no differences were found between bilingual and monolingual participants. We additionally found that age negatively predicts episodic memory, whereas playing mind teasers and educational level have positive relationships with episodic memory. CONCLUSIONS: Our results indicate that higher cognitive reserve, as measured by distributed educational training, higher level of education, and doing regular mental activities, is associated with better performance on episodic memory tasks in older adults. These results were discussed in connection with successful aging and protection against memory decline with aging.

Loop-Mediated Isothermal Amplification-Coupled Glass Nanopore Counting Toward Sensitive and Specific Nucleic Acid Testing.

Solid-state nanopores have shown great promise and achieved tremendous success in label-free single-molecule analysis. However, there are three common challenges in solid-state nanopore sensors, including the nanopore size variations from batch to batch that makes the interpretation of the sensing results difficult, the incorporation of sensor specificity, and the impractical analysis time at low analyte concentration due to diffusion-limited mass transport. Here, we demonstrate a novel loop-mediated isothermal amplification (LAMP)-coupled glass nanopore counting strategy that could effectively address these challenges. By using the glass nanopore in the counting mode (versus the sizing mode), the device fabrication challenge is considerably eased since it allows a certain degree of pore size variations and no surface functionalization is needed. The specific molecule replication effectively breaks the diffusion-limited mass transport thanks to the exponential growth of the target molecules. We show the LAMP-coupled glass nanopore counting has the potential to be used in a qualitative test as well as in a quantitative nucleic acid test. This approach lends itself to most amplification strategies as long as the target template is specifically replicated in numbers. The highly sensitive and specific sensing strategy would open a new avenue for solid-state nanopore sensors toward a new form of compact, rapid, low-cost nucleic acid testing at the point of care.

Calibration-Free Nanopore Digital Counting of Single Molecules.

Nanopore sensor conceptually represents an ideal single molecule counting device due to its unique partitioning-free, label-free electronic sensing. Existing theories and experiments have shown that sample concentration is proportional to the molecule translocation rate. However, a detailed nanopore geometry and size characterization or a calibration curve of concentration standards are often required for quantifying the unknown sample. In this work, we proposed and validated a calibration-free nanopore single molecule digital counting method for isolated molecule quantification. With the background ions as the in situ references, the molecule translocation rates can be normalized to the ion translocation rates (i.e., baseline current). This in situ reference alleviates the requirement for knowing the nanopore geometry and size or generating a calibration curve. In recognition of this effect, we developed a quantitative model for nanopore quantification without the need for prior knowledge of experimental conditions such as nanopore geometry, size, and applied voltage. This model was experimentally validated for different nanopores and DNA molecules with different sizes. We anticipate this calibration-free digital counting approach would provide a new avenue for nanopore-based molecule sensing.

To what extent is subjective well-being in late adulthood related to subjective and objective memory functioning? Five-year cross-lagged panel analyses.

BACKGROUND: Population aging motivated a focus in contemporary research on factors, e.g. cognitive functioning, that contribute to 'aging well.' However, something that has been overlooked is relation between memory functioning, determined by objective tests as well as subjective memory ratings, and subjective well-being (SWB). OBJECTIVES: The aim of the present study was to investigate cross-sectional and longitudinal (cross-lagged) relationships between episodic memory (both subjective and objective) and SWB. METHOD: A total of 586 older individuals (60-90 years) were assessed on multiple measures of the targeted constructs at baseline (Time 1) as part of the Betula cohort study. Five years later (Time 2), 354 of the participants returned for follow-up measurements and were included in cross-lagged panel analyses. RESULTS: As expected, objective memory and subjective memory showed a pattern of cross-sectional age deficits and a mean level longitudinal decline was observed for objective memory. By contrast, SWB showed stable mean levels both across age and time. No cross-sectional or cross-lagged associations were observed between SWB and objective memory, whereas subjective memory and SWB showed a cross-sectional association. CONCLUSION: The results underscore that successful aging is a multifaceted construct with no or only weak associations between the investigated components. However, SWB and rate of change at the individual level should be considered to define successful aging.

The relations between conscientiousness and mental health in a North-European and a West-Asian culture.

BACKGROUND: The relationship between conscientiousness, mental health and mental illness has been an issue for the last two decades. AIMS: By using a dual model of mental health, the present study examined a non-linear relationship between conscientiousness and healthy or non-healthy symptoms in two different cultures. METHOD: Participants in this study were 296 Iranian and 310 Swedish university students (18-24 years of age). We used two different conscientiousness scales; the 12-item conscientiousness subscale of the NEO/FFI as an imported (etic) scale, and a 10-item Iranian conscientiousness scale as an indigenous (emic) and culture-dependent scale. RESULTS: In both conscientiousness scales, multivariate analysis of variance showed that conscientiousness differentiated among four mental health groups (languishing, troubled, symptomatic and flourishing), although languishing and troubled individuals were less conscientious than flourishing and symptomatic individuals. Furthermore, the non-healthy symptomatic individuals were more conscientiousness than flourishing individuals. The results showed no significant differences between the two cultures in terms of the four mental health categories. CONCLUSIONS: It was concluded that the relationship between conscientiousness and mental health/mental illness is more a non-linear relationship than a linear one.

Three-Dimensional Numerical Simulations of Aspiration Process: Evaluation of Two Penumbra Aspiration Catheters Performance.

Acute ischemic stroke (AIS) is the leading cause of mortality and disability worldwide. AIS occur while cerebral arteries become blocked by embolism or thrombosis. Aspiration thrombectomy is a promising interventional device to extract massive clots from occluded cerebral arteries. The aim of this article is to develop a computer-aided method to clarify the performance of aspiration catheter and identify the risks of aspiration for each specific AIS patient. In order to simulate the aspiration process, a three-dimensional fluid-structure interaction (FSI) method was developed. The blood clot was modeled as a porous media which composed of viscoelastic fibrin networks. The finite element method (FEM) was implemented to compute the blood flow dynamics in the simplified cerebral vessel. The introduced clot model was validated by comparing the numerical results with experimental data. Furthermore, the analytical solution of the flow through the partially porous pipe was considered to validate FEM. In this research, the performance of two model of the Penumbra aspiration catheter-4MAX and 5MAX-were were compared at three distinct suction pressures. The aspiration ratio of the clot, aspiration time, amount of free fragments, wall shear stress (WSS), and extracted volume of the blood were calculated to evaluate catheters performance. At suction pressure -50 kPa, the aspiration ratio of 5MAX catheter reached 86.58% within 1.36 s. However, in 4MAX case, aspiration ratio of 76.41% was achieved within 1.39. Also, 5MAX catheter created 6.11% fewer free fragments in comparison to 4MAX. Hence, the possibility of distal embolization of 4MAX model was greater. However, the risk of vessel wall rupture was higher in 5MAX by considering mean WSS.

Developmental differences in episodic memory across school ages: evidence from enacted events performed by self and others.

The aim of this study was to examine action memory as a form of episodic memory among school-aged subjects. Most research on action memory has focused on memory changes in adult populations. This study explored the action memory of children over time. A total of 410 school-aged child participants, comprising 201 girls and 208 boys in four age groups (8, 10, 12, and 14), were included in this study. We studied two forms of action encoding, subject-performed tasks (SPTs) and experimenter-performed tasks (EPTs), which were compared with one verbal encoding task as a control condition. At retrieval, we used three memory tests (free recall, cued recall, and recognition). We observed significant differences in memory performance in children aged 8-14 years with respect to free recall and cued recall but not recognition. The largest memory enhancement was observed for the SPTs in the 8-14-year-old participants under all test conditions. Participants performed equally well on the free recall of SPTs and EPTs, whereas they displayed better performances on the cued recall and recognition of SPTs compared to EPTs. The strategic nature of SPTs and the distinction between item-specific information and relational information are discussed.

The role of executive functions in bilingual children with reading difficulties.

To explore the joint effect of reading difficulties (RD) and bilingualism on executive functions, 190 children of four groups of 9-12 year-olds (41 bilinguals with RD, 45 monolinguals with RD, 45 bilinguals without RD, and 59 monolinguals without RD) were examined on the Concentration game, Tower of Hanoi, and Stroop as measures of executive functioning tapping into inhibitory/attentional control, working memory and planning ability. The most prominent finding was that in terms of RD, the speed of performances decreased dramatically. This general decrease was more pronounced for bilingual children with RD than for their monolingual counterparts. In conclusion, the findings suggest that while bilinguals gain more from executive functions in normal reading, they lose in terms of RD. Such an outcome confirms that executive functions are essential components of both reading and bilingualism, which depending on whether reading conditions are normal or difficult will produce cognitive advantages or disadvantages. Further, it is argued that dissimilarity between the Farsi and Swedish languages may complicate handling of such a situation.

Comparing the effectiveness of emotion-focused and cognitive-behavioral therapies on body image, anxiety, and depression in women with PCOS.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a heterogeneous disease that is usually seen in women of reproductive age and causes complications such as body image dissatisfaction, anxiety, and depression. This study was done with the aim of comparing the effectiveness of emotion-focused therapy (EFT) and cognitive-behavioral therapy (CBT) on body image, anxiety, and depression in women with PCOS. MATERIALS AND METHODS: This research was semi-experimental with a pre-test-post-test design with control and follow-up groups. The statistical population included all women with PCOS who were referred to the infertility clinic of Afzalipur Hospital in Kerman in 2022. A total of 45 patients were selected as a sample using the convenience sampling method and then they were randomly assigned to two experimental groups (15 people each) and a control group (15 people). After the pre-test, the experimental groups were subjected to the interventions of EFT and CBT, and afterward the post-test was performed. Cash et al., body image questionnaire, and Beck anxiety and depression questionnaires were used. Data were analyzed using PSS21 software and analysis of variance. RESULTS: The findings revealed that the effectiveness of EFT and CBT on body image, anxiety, and depression is significant (P < 0.05). The comparison of the two therapy showed that the effect of CBT on body image, anxiety, and depression is more than EFT. Moreover, there was no statistically significant difference between the post-test and follow-up scores (P > 0.05). CONCLUSION: According to the results, CBT can reduce dissatisfaction with body image, anxiety, and depression in women with PCOS, therefore it is recommended to use this therapy.

DNA-PKcs Inhibition Improves Sequential Gene Insertion of the Full-Length CFTR cDNA in Airway Stem Cells.

Cystic fibrosis (CF) is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. Although many people with CF (pwCF) are treated using CFTR modulators, some are non-responsive due to their genotype or other uncharacterized reasons. Autologous airway stem cell therapies, in which the CFTR cDNA has been replaced, may enable a durable therapy for all pwCF. Previously, CRISPR-Cas9 with two AAVs was used to sequentially insert two halves of the CFTR cDNA and an enrichment cassette into the CFTR locus. However, the editing efficiency was <10% and required enrichment to restore CFTR function. Further improvement in gene insertion may enhance cell therapy production. To improve CFTR cDNA insertion in human airway basal stem cells (ABCs), we evaluated the use of the small molecules AZD7648 and ART558 which inhibit non-homologous end joining (NHEJ) and micro-homology mediated end joining (MMEJ). Adding AZD7648 alone improved gene insertion by 2-3-fold. Adding both ART558 and AZD7648 improved gene insertion but induced toxicity. ABCs edited in the presence of AZD7648 produced differentiated airway epithelial sheets with restored CFTR function after enrichment. Adding AZD7648 did not increase off-target editing. Further studies are necessary to validate if AZD7648 treatment enriches cells with oncogenic mutations.

Mediating Role of Inhibition Control in the Relationship Between Age and Memory Changes Throughout Adulthood: An Aging Developmental Study in Iran.

Introduction: This study aimed to investigate the age trends in various types of memory, including priming, working memory (WM), episodic memory (EM), and semantic memory (SM) from adulthood to old age, as well as the mediating role of inhibition control (IC) in the relationship between age and memory. Methods: A total of 796 healthy adults aged between 25 and 83 years participated in this cross-sectional study. They underwent assessment using a comprehensive battery of memory tests (adapted from the Betula battery), digit span tasks (to measure WM), and the Stroop color-word test (to measure IC). Results: The scatter plot with locally estimated scatterplot smoothing (LOESS) fitting line showed EM and WM declined steadily from age 25, while SM exhibited a mild increase up to age 55 followed by a decline. Priming did not show significant changes with age. Mediation analysis and bootstrap tests indicated that IC mediated the relationship between age and EM (ß=-0.097, P=0.002) and between age and SM (ß=-0.086, P=0.001). Conclusion: Our results showed that age affects various types of memory differently, and inhibition control plays a fundamental mediating role in explaining age-related declines in SM and EM.

Single-Stranded DNA with Internal Base Modifications Mediates Highly Efficient Gene Insertion in Primary Cells.

Single-stranded DNA (ssDNA) templates along with Cas9 have been used for gene insertion but suffer from low efficiency. Here, we show that ssDNA with chemical modifications in 10-17% of internal bases (eDNA) is compatible with the homologous recombination machinery. Moreover, eDNA templates improve gene insertion by 2-3 fold compared to unmodified and end-modified ssDNA in airway basal stem cells (ABCs), hematopoietic stem and progenitor cells (HSPCs), T-cells and endothelial cells. Over 50% of alleles showed gene insertion in three clinically relevant loci (CFTR, HBB, and CCR5) in ABCs using eDNA and up to 70% of alleles showed gene insertion in the HBB locus in HSPCs. This level of correction is therapeutically relevant and is comparable to adeno-associated virus-based templates. Knocking out TREX1 nuclease improved gene insertion using unmodified ssDNA but not eDNA suggesting that chemical modifications inhibit TREX1. This approach can be used for therapeutic applications and biological modeling.

Morphology around Nanopores Fabricated by Laser-Assisted Dielectric Breakdown and Its Impact on Ion and DNA Transport and Sensing.

Laser-assisted controlled dielectric breakdown (LaCBD) has emerged as an alternative to conventional CBD-based nanopore fabrication due to its localization capability, facilitated by the photothermal-induced thinning down in the hot spot. Here, we reported the potential impact of the laser on forming debris around the nanopore region in LaCBD. The debris was clearly observable by scanning electron microscopy (SEM) and photoluminescence (PL) spectroscopy. We found that debris formation is a unique phenomenon in LaCBD that is not observable in the conventional CBD approach. We also found that the LaCBD-induced debris is more evident when the laser power and voltage stress are higher. Moreover, the debris is asymmetrically distributed on the top and bottom sides of the membrane. We also found unexpected rectified ionic and molecular transport in those LaCBD nanopores with debris. Based on these observations, we developed and validated a model describing the debris formation kinetics in LaCBD by considering the generation, diffusion, drift, and gravity in viscous mediums. These findings indicate that while laser aids in nanopore localization, precautions should be taken due to the potential formation of debris and rectification of molecular transport. This study provides valuable insights into the kinetics of LaCBD and the characteristics of the LaCBD nanopore.

STAMP-Based Digital CRISPR-Cas13a for Amplification-Free Quantification of HIV-1 Plasma Viral Loads.

Quantification of HIV RNA in plasma is critical for identifying the disease progression and monitoring the effectiveness of antiretroviral therapy. While RT-qPCR has been the gold standard for HIV viral load quantification, digital assays could provide an alternative calibration-free absolute quantification method. Here, we reported a Self-digitization Through Automated Membrane-based Partitioning (STAMP) method to digitalize the CRISPR-Cas13 assay (dCRISPR) for amplification-free and absolute quantification of HIV-1 viral RNAs. The HIV-1 Cas13 assay was designed, validated, and optimized. We evaluated the analytical performances with synthetic RNAs. With a membrane that partitions ∼100 nL of reaction mixture (effectively containing 10 nL of input RNA sample), we showed that RNA samples spanning 4 orders of dynamic range between 1 fM (∼6 RNAs) to 10 pM (∼60k RNAs) could be quantified as fast as 30 min. We also examined the end-to-end performance from RNA extraction to STAMP-dCRISPR quantification using 140 µL of both spiked and clinical plasma samples. We demonstrated that the device has a detection limit of approximately 2000 copies/mL and can resolve a viral load change of 3571 copies/mL (equivalent to 3 RNAs in a single membrane) with 90% confidence. Finally, we evaluated the device using 140 µL of 20 patient plasma samples (10 positives and 10 negatives) and benchmarked the performance with RT-PCR. The STAMP-dCRISPR results agree very well with RT-PCR for all negative and high positive samples with Ct < 32. However, the STAMP-dCRISPR is limited in detecting low positive samples with Ct > 32 due to the subsampling errors. Our results demonstrated a digital Cas13 platform that could offer an accessible amplification-free quantification of viral RNAs. By further addressing the subsampling issue with approaches such as preconcentration, this platform could be further exploited for quantitatively determining viral load for an array of infectious diseases.

The effects of marital status on episodic and semantic memory in healthy middle-aged and old individuals.

The present study examined the influences of marital status on different episodic and semantic memory tasks. A total of 1882 adult men and women participated in a longitudinal project (Betula) on memory, health and aging. The participants were grouped into two age cohorts, 35-60 and 65-85, and studied over a period of 5 years. Episodic memory tasks concerned recognition and recall, whereas semantic memory tasks concerned knowledge and fluency. The results showed, after controlling for education, some diseases, chronological age and leisure activity as covariates, that there were significant differences between married and single individuals in episodic memory, but not in semantic memory. Married people showed significantly better memory performances than singles in both subsystems of episodic memory, that is, recall and recognition. Also, the rate of decline in episodic memory was significantly larger for singles and widowed than other groups over the 5-year time period in both age groups. The findings demonstrate that the positive relation found between marriage and health can be extended to the relation between marriage and cognitive performance. This effect might be explained by the role played by cognitive stimulation in memory and cognition.