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Introduction: Females may have greater susceptibility to Alzheimer's disease (AD)‐pathology. We examined the effect of sex on pathology, neurodegeneration, and memory in cognitively‐unimpaired Presenilin‐1 (PSEN1) E280A mutation carriers and non‐carriers. Methods: We analyzed baseline data from 167 mutation carriers and 75 non‐carriers (ages 30 to 53) from the Alzheimer's Prevention Initiative Autosomal Dominant AD Trial, including florbetapir‐ and fludeoxyglucose‐PET, MRI based hippocampal volume and cognitive testing. Results: Females exhibited better delayed recall than males, controlling for age, precuneus glucose metabolism, and mutation status, although the effect was not significant among PSEN1 mutation carriers only. APOE ε4 did not modify the effect of sex on AD biomarkers and memory. Discussion: Our findings suggest that, among cognitively‐unimpaired individuals at genetic risk for autosomal‐dominant AD, females may have greater cognitive resilience to AD pathology and neurodegeneration than males. Further investigation of sex‐specific differences in autosomal‐dominant AD is key to elucidating mechanisms of AD risk and resilience. [ABSTRACT FROM AUTHOR]

Objective: Subjective Cognitive Decline (SCD) may be an early indicator of risk for Alzheimer's disease (AD). Findings regarding sex differences in SCD are inconsistent. Studying sex differences in SCD within cognitively unimpaired individuals with autosomal-dominant AD (ADAD), who will develop dementia, may inform sex-related SCD variations in preclinical AD. We examined sex differences in SCD within cognitively unimpaired mutation carriers from the world's largest ADAD kindred and sex differences in the relationship between SCD and memory performance. Methods: We included 310 cognitively unimpaired Presenilin-1 (PSEN-1) E280A mutation carriers (51% females) and 1998 noncarrier family members (56% females) in the study. Subjects and their study partners completed SCD questionnaires and the CERAD word list delayed recall test. ANCOVAs were conducted to examine group differences in SCD, sex, and memory performance. In carriers, partial correlations were used to examine associations between SCD and memory performance covarying for education. Results: Females in both groups had greater self-reported and study partner-reported SCD than males (all p < 0.001). In female mutation carriers, greater self-reported (p = 0.02) and study partner-reported SCD (p < 0.001) were associated with worse verbal memory. In male mutation carriers, greater self-reported (p = 0.03), but not study partner-reported SCD (p = 0.11) was associated with worse verbal memory. Conclusions: Study partner-reported SCD may be a stronger indicator of memory decline in females versus males in individuals at risk for developing dementia. Future studies with independent samples and preclinical trials should consider sex differences when recruiting based on SCD criteria. [ABSTRACT FROM AUTHOR]

Neuropsychologists continue to face challenges when assessing Spanish-speaking individuals due to limited availability of normative data. We developed comprehensive normative data stratified by age and education for a Spanish neuropsychological test battery used by the Grupo de Neurociencias de Antioquia (Colombia) and the Colombian Alzheimer's Prevention Initiative Registry, which have followed large families at risk for autosomal-dominant Alzheimer's disease (ADAD) since the 1990s. Approximately 75% of these individuals are cognitively-unimpaired and are not genetically predisposed to develop ADAD. We conducted a retrospective study on neuropsychological evaluations from 2,673 cognitively unimpaired individuals (56% female), with ages ranging from 18 to 86 years and education from 1 to 25 years. Neuropsychological measures included the Consortium to Establish a Registry for Alzheimer's Disease-Colombia, and other multidomain Spanish tests. We examined associations between age, education, and sex with cognitive performance. Norms stratified by age and education are presented. Cognitive performance showed small associations with age and education and was unrelated to sex. We provided population-based norms for Spanish tests targeting multiple cognitive domains using a large Colombian sample. These normative data may be helpful for the neuropsychological characterization of Spanish speakers from Latin America in clinical and research settings. [ABSTRACT FROM AUTHOR]

Introduction: The API AutosomalDominant AD (ADAD) Colombia Trial is a placebo‐controlled clinical trial of crenezumab in 252 cognitively unimpaired 30 to 60‐year‐old Presenilin 1 (PSEN1) E280A kindred members, including mutation carriers randomized to active treatment or placebo and non‐carriers who receive placebo. Methods: Of the 252 enrolled, we present data on a total of 242 mutation carriers and non‐carriers matched by age range, excluding data on 10 participants to protect participant confidentiality, genetic status, and trial integrity. Results: We summarize demographic, clinical, cognitive, and behavioral data from 167 mutation carriers and 75 non‐carriers, 30 to 53 years of age. Carriers were significantly younger than non‐carriers ((mean age ± SD) 37 ± 5 vs 42 ± 6), had significantly lower Mini Mental Status Exam (MMSE) scores (28.8 ± 1.4 vs 29.2 ± 1.0), and had consistently lower memory scores. Discussion: Although PSEN1 E280A mutation carriers in the Trial are cognitively unimpaired, they have slightly lower MMSE and memory scores than non‐carriers. Their demographic characteristics are representative of the local population. [ABSTRACT FROM AUTHOR]

Background: This study aimed to determine Consortium to Establish a Registry for Alzheimer's Disease (CERAD) Neuropsychological Assessment Battery total score diagnostic accuracy in the diagnosis of mild cognitive impairment (MCI) and dementia in familial Alzheimer's disease (FAD) with E280A mutation on presenilin-1 gene (PSEN1).Methods: A cross-sectional study was conducted in a cohort of PSEN1 E280A carriers and non-carriers assessed between January 1995 and February 2013. During the first neuropsychological assessment, 76 were having dementia, 46 had MCI, and 1,576 were asymptomatic. CERAD cut-off points were established for MCI and dementia using a Receiver Operating Characteristics (ROC) analysis, and were further analyzed according to education level in two groups: low education level (eight years or less), and high education level (over eight years).Results: The area under curve-ROC CERAD total score for dementia was 0.994 (95% CI = 0.989-0.999), and that for MCI was 0.862 (95% CI = 0.816-0.908). The dementia diagnosis cut-off point for the low education group was 54, (98.4% sensitivity, 92.6% specificity), and that for the high education group was 67 (100% sensitivity, 94.1% specificity). The MCI diagnosis cut-off point for the low education group was 66 (91.2% sensitivity, 56.4% specificity), and that for the high education group was 72 (91.7% sensitivity, 76.3% specificity).Conclusions: The CERAD total score is a useful screening tool for dementia and MCI in a population at risk of FAD. [ABSTRACT FROM AUTHOR]

In this project of investigation was designed the system of dosage and injection of fertilizers using a microcontrolled system. The microcontrolled system receives the information of the quantity of fertilizer that needs the soil for his nutrition, and it sends signals to a mechanical device to regulate the step of the fertilizer doing the exact dosage of the product. Finally, a system of injection introduces the fertilizer inside the soil. [ABSTRACT FROM AUTHOR]

Background: Growing evidence suggests that females have greater biological risk for Alzheimer's disease (AD). As levels of AD pathology increase, females show greater tau accumulation, faster hippocampal volume loss, and faster cognitive decline than males. We sought to investigate sex differences in individuals with preclinical autosomal dominant AD (ADAD), who are destined to develop early‐onset dementia and have minimal age‐related confounds known to vary by sex (e.g., mortality, cardiovascular disease, or menopause). We plan to examine the role of sex in the associations among markers of pathology, neurodegeneration, and cognition leveraging baseline data from the Alzheimer's Prevention Initiative (API) ADAD Colombia Trial. Methods: We analyzed baseline data from 242 cognitively unimpaired 30‐53 year‐old prevention trial participants, including 167 PSEN1 E280A mutation carriers and 75 non‐carrier family members. Clinical ratings, CERAD word list delayed recall, hippocampal grey matter volume, florbetapir cortical‐to‐pontine standard‐uptake value ratios (SUVR), and precuneus 18F‐fludeoxyglucose (FDG) positron emission tomography were included in the analyses. T‐tests and multiple regressions models controlling for age, PSEN1 mutation status and amyloid burden were conducted. Results: Across groups, females had greater hippocampal volumes (p=.05) and better delayed recall (p=.005) than males. Female carriers were younger than male carriers (p=.04). Females continued to have better delayed recall after adjusting for glucose metabolism in the precuneus (Sex: β=.562, p=.023), and showed a trend towards significance after adjusting for hippocampal volumes (Sex: β=.462, p=.059). In carriers only, as age increased, males had lower hippocampal volumes than females (Slope difference: p ≤.05), while no differences were found in amyloid levels or metabolism. There was no sex difference in the relationship between amyloid accumulation, hippocampal volumes (Sex: β=.000, p=.094), and metabolism (Sex: β=‐.004, p=.815). Conclusion: Findings suggest that cognitively unimpaired female mutation carriers may have greater cognitive resilience to AD‐related neurodegeneration compared to male mutation carriers. Further investigation of sex‐specific differences in AD‐related clinical and pathological markers is key to inform AD detection, prevention, and development of treatments. [ABSTRACT FROM AUTHOR]

Cyanobacterial metabolites are increasingly studied, in regards to their biosynthesis, ecological role, toxicity, and potential biomedical applications. However, the history of cyanotoxins prior to the last few decades is virtually unknown. Only a few paleolimnological studies have been undertaken to date, and these have focused exclusively on microcystins and cylindrospermopsins, both successfully identified in lake sediments up to 200 and 4700 years old, respectively. In this paper, we review direct extraction, quantification, and application of cyanotoxins in sediment cores, and put forward future research prospects in this field. Cyanobacterial toxin research is also compared to other paleo-cyanobacteria tools, such as sedimentary pigments, akinetes, and ancient DNA isolation, to identify the role of each tool in reproducing the history of cyanobacteria. Such investigations may also be beneficial for further elucidation of the biological role of cyanotoxins, particularly if coupled with analyses of other abiotic and biotic sedimentary features. In addition, we identify current limitations as well as future directions for applications in the field of paleolimnological studies on cyanotoxins. [ABSTRACT FROM AUTHOR]

Introduction: Females may have greater susceptibility to Alzheimer's disease (AD)-pathology. We examined the effect of sex on pathology, neurodegeneration, and memory in cognitively-unimpaired Presenilin-1 (PSEN1) E280A mutation carriers and non-carriers., Methods: We analyzed baseline data from 167 mutation carriers and 75 non-carriers (ages 30 to 53) from the Alzheimer's Prevention Initiative Autosomal Dominant AD Trial, including florbetapir- and fludeoxyglucose-PET, MRI based hippocampal volume and cognitive testing., Results: Females exhibited better delayed recall than males, controlling for age, precuneus glucose metabolism, and mutation status, although the effect was not significant among PSEN1 mutation carriers only. APOE ε4 did not modify the effect of sex on AD biomarkers and memory., Discussion: Our findings suggest that, among cognitively-unimpaired individuals at genetic risk for autosomal-dominant AD, females may have greater cognitive resilience to AD pathology and neurodegeneration than males. Further investigation of sex-specific differences in autosomal-dominant AD is key to elucidating mechanisms of AD risk and resilience., (© 2021 the Alzheimer's Association.)

Introduction: The API AutosomalDominant AD (ADAD) Colombia Trial is a placebo-controlled clinical trial of crenezumab in 252 cognitively unimpaired 30 to 60-year-old Presenilin 1 (PSEN1) E280A kindred members, including mutation carriers randomized to active treatment or placebo and non-carriers who receive placebo., Methods: Of the 252 enrolled, we present data on a total of 242 mutation carriers and non-carriers matched by age range, excluding data on 10 participants to protect participant confidentiality, genetic status, and trial integrity., Results: We summarize demographic, clinical, cognitive, and behavioral data from 167 mutation carriers and 75 non-carriers, 30 to 53 years of age. Carriers were significantly younger than non-carriers ((mean age ± SD) 37 ± 5 vs 42 ± 6), had significantly lower Mini Mental Status Exam (MMSE) scores (28.8 ± 1.4 vs 29.2 ± 1.0), and had consistently lower memory scores., Discussion: Although PSEN1 E280A mutation carriers in the Trial are cognitively unimpaired, they have slightly lower MMSE and memory scores than non-carriers. Their demographic characteristics are representative of the local population., (© 2020 The Authors. Alzheimer's & Dementia published by Wiley Periodicals LLC on behalf of Alzheimer's Association.)