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Proactive Semantic Interference (PSI) and failure to recover from PSI (frPSI), are novel constructs assessed by the LASSI-L. These measures are sensitive to cognitive changes in early Mild Cognitive Impairment (MCI) and preclinical AD determined by Aß load using PET. The goal of this study was to compare a new computerized version of the LASSI-L (LASSI-Brief Computerized) to the standard paper-and-pencil version of the test. In this study, we examined 110 cognitively unimpaired (CU) older adults and 79 with amnestic MCI (aMCI) who were administered the paper-and-pencil form of the LASSI-L. Their performance was compared with 62 CU older adults and 52 aMCI participants examined using the LASSI-BC. After adjustment for covariates (degree of initial learning, sex, education, and language of evaluation) both the standard and computerized versions distinguished between aMCI and CU participants. The performance of CU and aMCI groups using either form was relatively commensurate. Importantly, an optimal combination of Cued B2 recall and Cued B1 intrusions on the LASSI-BC yielded an area under the ROC curve of .927, a sensitivity of 92.3% and specificity of 88.1%, relative to an area under the ROC curve of .815, a sensitivity of 72.5%, and a specificity of 79.1% obtained for the paper-and-pencil LASSI-L. Overall, the LASSI-BC was comparable, and in some ways, superior to the paper-and-pencil LASSI-L. Advantages of the LASSI-BC include a more standardized administration, suitability for remote assessment, and an automated scoring mechanism that can be verified by a built-in audio recording of responses.

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BACKGROUND: Evaluation of students' learning strategies can enhance academic support. Few studies have investigated differences in learning strategies between male and female students as well as their impact on United States Medical Licensing Examination® (USMLE) Step 1 and preclinical performance. METHODS: The Learning and Study Strategies Inventory (LASSI) was administered to the classes of 2019-2024 (female (n = 350) and male (n = 262)). Students' performance on preclinical first-year (M1) courses, preclinical second-year (M2) courses, and USMLE Step 1 was recorded. An independent t-test evaluated differences between females and males on each LASSI scale. A Pearson product moment correlation determined which LASSI scales correlated with preclinical performance and USMLE Step 1 examinations. RESULTS: Of the 10 LASSI scales, Anxiety, Attention, Information Processing, Selecting Main Idea, Test Strategies and Using Academic Resources showed significant differences between genders. Females reported higher levels of Anxiety (p < 0.001), which significantly influenced their performance. While males and females scored similarly in Concentration, Motivation, and Time Management, these scales were significant predictors of performance variation in females. Test Strategies was the largest contributor to performance variation for all students, regardless of gender. CONCLUSION: Gender differences in learning influence performance on STEP1. Consideration of this study's results will allow for targeted interventions for academic success.

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Introduction: This study investigated the role of proactive semantic interference (frPSI) in predicting the progression of amnestic Mild Cognitive Impairment (aMCI) to dementia, taking into account various cognitive and biological factors. Methods: The research involved 89 older adults with aMCI who underwent baseline assessments, including amyloid PET and MRI scans, and were followed longitudinally over a period ranging from 12 to 55 months (average 26.05 months). Results: The findings revealed that more than 30% of the participants diagnosed with aMCI progressed to dementia during the observation period. Using Cox Proportional Hazards modeling and adjusting for demographic factors, global cognitive function, hippocampal volume, and amyloid positivity, two distinct aspects of frPSI were identified as significant predictors of a faster decline to dementia. These aspects were fewer correct responses on a frPSI trial and a higher number of semantic intrusion errors on the same trial, with 29.5% and 31.6 % increases in the likelihood of more rapid progression to dementia, respectively. Discussion: These findings after adjustment for demographic and biological markers of Alzheimer's Disease, suggest that assessing frPSI may offer valuable insights into the risk of dementia progression in individuals with aMCI.

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Introduction: Semantic intrusion errors (SI) have distinguished between those with amnestic Mild Cognitive Impairment (aMCI) who are amyloid positive (A+) versus negative (A-) on positron emission tomography (PET). Method: This study examines the association between SI and plasma - based biomarkers. One hundred and twenty-eight participants received SiMoA derived measures of plasma pTau-181, ratio of two amyloid-ß peptide fragments (Aß42/Aß40), Neurofilament Light protein (NfL), Glial Fibrillary Acidic Protein (GFAP), ApoE genotyping, and amyloid PET imaging. Results: The aMCI A+ (n = 42) group had a higher percentage of ApoE ɛ4 carriers, and greater levels of pTau-181 and SI, than Cognitively Unimpaired (CU) A- participants (n = 25). CU controls did not differ from aMCI A- (n = 61) on plasma biomarkers or ApoE genotype. Logistic regression indicated that ApoE ɛ4 positivity, pTau-181, and SI were independent differentiating predictors (Correct classification = 82.0%; Sensitivity = 71.4%; Specificity = 90.2%) in identifying A+ from A- aMCI cases. Discussion: A combination of plasma biomarkers, ApoE positivity and SI had high specificity in identifying A+ from A- aMCI cases.

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Background and objectives: Cognitive decline is an important early sign in pre-motor manifest Huntington's disease (preHD) and is characterized by deficits across multiple domains including executive function, psychomotor processing speed, and memory retrieval. Prior work suggested that the Loewenstein-Acevedo Scale for Semantic Interference and Learning (LASSI-L)-a verbal learning task that simultaneously targets these domains - could capture early cognitive changes in preHD. The current study aimed to replicate, validate and further analyze the LASSI-L in preHD using larger datasets. Methods: LASSI-L was administered to 50 participants (25 preHD and 25 Healthy Controls) matched for age, education, and sex in a longitudinal study of disease progression and compared to performance on MMSE, Trail A & B, SCWT, SDMT, Semantic Fluency (Animals), and CVLT-II. Performance was then compared to a separate age-education matched-cohort of 25 preHD participants. Receiver operating curve (ROC) and practice effects (12 month interval) were investigated. Group comparisons were repeated using a preHD subgroup restricted to participants predicted to be far from diagnosis (Far subgroup), based on CAG-Age-Product scaled (CAPs) score. Construct validity was assessed through correlations with previously established measures of subcortical atrophy. Results: PreHD performance on all sections of the LASSI-L was significantly different from controls. The proactive semantic interference section (PSI) was sensitive (p = 0.0001, d = 1.548), similar across preHD datasets (p = 1.0), reliable on test-retest over 12 months (spearman rho = 0.88; p = <0.00001) and associated with an excellent area under ROC (AUROC) of 0.855. In the preHD Far subgroup comparison, PSI was the only cognitive assessment to survive FDR < 0.05 (p = 0.03). The number of intrusions on PSI was negatively correlated with caudate volume. Discussion: The LASSI-L is a sensitive, reliable, efficient tool for detecting cognitive decline in preHD. By using a unique verbal learning test paradigm that simultaneously targets executive function, processing speed and memory retrieval, the LASSI-L outperforms many other established tests and captures early signs of cognitive impairment. With further longitudinal validation, the LASSI-L could prove to be a useful biomarker for clinical research in preHD.

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OBJECTIVE: Growth performance and growth-related traits have a crucial role in livestock due to their influence on productivity. This genome-wide association study (GWAS) in Pakistani dromedary camels was conducted to identify single nucleotide polymorphisms (SNPs) associated with growth at specific camel ages, and for selected SNPs, to investigate in detail how their effects change with increasing camel age. This is the first GWAS conducted on dromedary camels in this region. METHODS: Two Pakistani breeds, Marecha and Lassi, were selected for this study. A genotypingby-sequencing method was used, and a total of 65,644 SNPs were identified. For GWAS, weight records data with several body weight traits, namely, birthweight, weaning weight, and weights of camels at 1, 2, 4, and 6 years of age were analysed by using model-based growth curve analysis. Age-specific weight data were analysed with a linear mixed model that included fixed effects of SNP genotype as well as sex. RESULTS: Based on the q-value method for false discovery control, for Marecha camels, five SNPs at q<0.01 and 96 at q<0.05 were significantly associated with the weight traits considered, while three (q<0.01) and seven (q<0.05) SNP associations were identified for Lassi camels. Several candidate genes harbouring these SNP were discovered. CONCLUSION: These results will help to better understand the genetic architecture of growth including how these genes are expressed at different phases of their life. This will serve to lay the foundations for applied breeding programs of camels by allowing the genetic selection of superior animals.

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ABSTRACTThis study compares semantic and phonological interference vulnerability across the full range of learning processes. Method: 43 controls aged 61-88 underwent a neuropsychological examination, French adaptation of the LASSI-L, and an experimental phonological test, the TIP-A. Paired sample t-tests, factorial ANOVA and hierarchical regressions were conducted, psychometric properties were calculated. Results: TIP-A efficiently generated phonological interference between concurrent word lists and was associated with short-term memory, unlike LASSI-L. On LASSI-L, proactive interference was higher than retroactive interference; the opposite pattern was found on TIP-A. Memory performance was better explained by age in the semantic than in the phonological task. Age was not associated with interference vulnerability. Intrusions and false recognition were associated with cognitive functioning regardless of age, particularly in the semantic context. Conclusion: To our knowledge, this is the first study to assess phonological and semantic interference using homologous concurrent word list tasks, and not a working memory build-up or DRM paradigm. The pattern obtained illustrates the weak initial memory trace in a phonological context and results are discussed according to depth-of-processing and dual-process theories. Similar paradigms could be studied among various pathologies for a better understanding of generalised interference vulnerability vs. specific semantic or phonological impairment.

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During the prodromal stage of Alzheimer's disease (AD), neurodegenerative changes can be identified by measuring volumetric loss in AD-prone brain regions on MRI. Cognitive assessments that are sensitive enough to measure the early brain-behavior manifestations of AD and that correlate with biomarkers of neurodegeneration are needed to identify and monitor individuals at risk for dementia. Weak sensitivity to early cognitive change has been a major limitation of traditional cognitive assessments. In this study, we focused on expanding our previous work by determining whether a digitized cognitive stress test, the Loewenstein-Acevedo Scales for Semantic Interference and Learning, Brief Computerized Version (LASSI-BC) could differentiate between Cognitively Unimpaired (CU) and amnestic Mild Cognitive Impairment (aMCI) groups. A second focus was to correlate LASSI-BC performance to volumetric reductions in AD-prone brain regions. Data was gathered from 111 older adults who were comprehensively evaluated and administered the LASSI-BC. Eighty-seven of these participants (51 CU; 36 aMCI) underwent MR imaging. The volumes of 12 AD-prone brain regions were related to LASSI-BC and other memory tests correcting for False Discovery Rate (FDR). Results indicated that, even after adjusting for initial learning ability, the failure to recover from proactive semantic interference (frPSI) on the LASSI-BC differentiated between CU and aMCI groups. An optimal combination of frPSI and initial learning strength on the LASSI-BC yielded an area under the ROC curve of 0.876 (76.1% sensitivity, 82.7% specificity). Further, frPSI on the LASSI-BC was associated with volumetric reductions in the hippocampus, amygdala, inferior temporal lobes, precuneus, and posterior cingulate.

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The 'Imi Ho'ola Post-Baccalaureate Program is a proven pathway to medicine that has significantly increased the number of underrepresented and disadvantaged students that complete medical school in Hawai'i. A recent program evaluation indicated a relationship between student success and the significance of attitude and purpose from the Learning and Study Strategies Inventory. Curricular innovations in a 5-week introductory course during Phase 1, lay the foundation to promote a healthy attitude with purpose-led activities, such as personalized journal vision covers, weekly journal reflections, a multimedia autobiography, and projects focusing on medical specialties, well-being, and resiliency. Such purposeful innovations are vital for the success of underrepresented students, with the ultimate intent to diversify the physician workforce and to increase the number of physicians serving in underrepresented and underserved communities in Hawai'i and throughout the Pacific.

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OBJECTIVES: This study examines differences in the Learning and Study Strategies Inventory (LASSI) 10-subscale scores between low and high academically performing medical students relative to internal and external examinations. METHODS: The LASSI instrument was administered to 180 medical students from three classes (2016, 2017, and 2018). To measure the strength of association between LASSI 10-subscale scores and performance on overall biomedical sciences and the United States Medical Licensing Examination (USMLE) Step 1, Pearson product-moment correlation analyses were performed. One-way ANOVA and Bonferroni post-hoc analyses were performed to identify statistically significant differences on LASSI scores between students grouped by quartiles according to their performance on USMLE Step 1 examination (external performance measure) and by their average letter grade in the overall biomedical sciences (internal performance measure). RESULTS: Significant associations were observed between Anxiety, Motivation, and Test Strategies and students' performance on both overall biomedical sciences and USMLE Step 1 examinations. Anxiety, Motivation, and Test Strategies were different between "A" and "C" students in the overall biomedical sciences. Anxiety, Information Processing, Motivation, Selecting Main Idea, and Test Strategies were significantly different between the upper and lower quartiles in USMLE Step 1 student performance. CONCLUSIONS: Anxiety, Motivation and Test Strategies are the main LASSI subscales that were significantly different between high-performing and low-performing students for internal and external examinations. Interestingly, the same LASSI subscales Anxiety, Motivation, and Test Strategies were correlated with students' performance in internal and external examinations.

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INTRODUCTION: The purpose of this study was to determine whether a study skills course taken by first professional year pharmacy students improved their self-assessment of study skills and strategies. METHODS: This study analyzed student responses to the Learning and Study Strategies Inventory (LASSI), an online assessment with questions in 10 subject areas: anxiety, motivation, concentration, test strategies, study aids, selecting main ideas, attitude, self-testing, information processing, and time management. Students in an elective study skills course in 2012-2017 completed the self-assessment prior to and at the end of the course. Wilcoxon signed-rank test was performed to compare class score pre- and post-course. RESULTS: Over a five-year period, 312 students completed both the pre- and post-course LASSI assessment. Average percentile scores increased significantly from the beginning to the end of the course in all 10 areas. Notably, average pre-course scores in seven subject areas (attention, concentration, self-testing, selecting main ideas, study aids, time management, and test strategies) were all below the 50th percentile, indicating a need for improvement in those skills to see increased academic success. Average post-course scores in each area increased to between the 50th and 75th percentile. CONCLUSIONS: This evaluation shows that a study skills course improves students' self-assessment of skills and attitudes associated with success in post-secondary education. Future studies will look at the effect of such a course on academic outcomes.

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OBJECTIVE: A number of older adults obtain normal scores on formal cognitive tests, but present clinical concerns that raise suspicion of cognitive decline. Despite not meeting full criteria for Mild Cognitive Impairment (MCI), these PreMCI states confer risk for progression to Alzheimer's disease (AD). This investigation addressed a pressing need to identify cognitive measures that are sensitive to PreMCI and are associated with brain biomarkers of neurodegeneration. METHOD: Participants included 49 older adults with a clinical history suggestive of cognitive decline but normal scores on an array of neuropsychological measures, thus not meeting formal criteria for MCI. The performance of these PreMCI participants were compared to 117 cognitively normal (CN) elders on the LASSI-L, a cognitive stress test that uniquely assesses the failure to recover from proactive semantic interference effects (frPSI). Finally, a subset of these individuals had volumetric analyses based on MRI scans. RESULTS: PreMCI participants evidenced greater LASSI- L deficits, particularly with regards to frPSI and delayed recall, relative to the CN group. No differences on MRI measures were observed. Controlling for false discovery rate (FDR), frPSI was uniquely related to increased dilatation of the inferior lateral ventricle and decreased MRI volumes in the hippocampus, precuneus, superior parietal region, and other AD prone areas. In contrast, other LASSI-L indices and standard memory tests were not related to volumetric findings. CONCLUSIONS: Despite equivalent performance on traditional memory measures, the frPSI distinguished between PreMCI and CN elders and was associated with reductions in brain volume in numerous AD-relevant brain regions.

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BACKGROUND: The rise in incidence of Alzheimer's disease (AD) has led to efforts to advance early detection of the disease during its preclinical stages. To achieve this, the field needs to develop more sensitive cognitive tests that relate to biological markers of disease pathology. Failure to recover from proactive interference (frPSI) is one such cognitive marker that is associated with volumetric reductions in the hippocampus, precuneus, and other AD-prone regions, and to amyloid load in the brain. OBJECTIVE: The current study attempted to replicate and extend our previous findings that frPSI is a sensitive marker of early AD, and related to a unique pattern of volumetric loss in AD prone areas. METHODS: Three different memory measures were examined relative to volumetric loss and cortical thickness among 45 participants with amnestic mild cognitive impairment. RESULTS: frPSI was uniquely associated with reduced volumes in the hippocampus (r = 0.50) precuneus (r = 0.41), and other AD prone regions, replicating previous findings. Strong associations between frPSI and lower entorhinal cortex volumes and cortical thickness (r≥0.60) and precuneus (r = 0.50) were also observed. CONCLUSION: Unique and strong associations between volumetric reductions and frPSI as observed by Loewenstein and colleagues were replicated. Together with cortical thickness findings, these results indicate that frPSI is worthy of further study as a sensitive and early cognitive marker of AD.

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BACKGROUND: There is growing evidence that proactive semantic interference (PSI) and failure to recover from PSI may represent early features of Alzheimer's disease (AD). OBJECTIVE: This study investigated the association between PSI, recovery from PSI, and reduced MRI volumes in AD signature regions among cognitively impaired and unimpaired older adults. METHODS: Performance on the LASSI-L (a novel test of PSI and recovery from PSI) and regional brain volumetric measures were compared between 38 cognitively normal (CN) elders and 29 older participants with amnestic mild cognitive impairment (MCI). The relationship between MRI measures and performance on the LASSI-L as well as traditional memory and non-memory cognitive measures was also evaluated in both diagnostic groups. RESULTS: Relative to traditional neuropsychological measures, MCI patients' failure to recover from PSI was associated with reduced volumes in the hippocampus (rs = 0.48), precuneus (rs = 0.50); rostral middle frontal lobules (rs = 0.54); inferior temporal lobules (rs = 0.49), superior parietal lobules (rs = 0.47), temporal pole (rs = 0.44), and increased dilatation of the inferior lateral ventricle (rs = -0.49). For CN elders, only increased inferior lateral ventricular size was associated with vulnerability to PSI (rs = -0.49), the failure to recover from PSI (rs = -0.57), and delayed recall on the Hopkins Verbal Learning Test-Revised (rs = -0.48). DISCUSSION: LASSI-L indices eliciting failure to recover from PSI were more highly associated with more MRI regional biomarkers of AD than other traditional cognitive measures. These results as well as recent amyloid imaging studies with otherwise cognitively normal subjects, suggest that recovery from PSI may be a sensitive marker of preclinical AD and deserves further investigation.

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The aim of present work was to investigate preventive role of orally administered Aloe vera supplemented probiotic lassi (APL) on Shigella dysenteriae infection in mice. At the end of experimental period (2, 5 and 7 days of challenging), different organs such as spleen, liver, small intestine, large intestine, and peritoneal fluid were collected and assessed for Shigella colonization. Secretary IgA was estimated in intestinal fluid. Blood was collected in heparinized tubes for various haematological studies. Oral administration of APL showed a significant (p < 0.05) reduction in the Shigella counts (log cfu/mL) in all organs as compared to other treatment groups at different intervals after post feeding. Similarly, secretary IgA antibody levels (µg/mL) in intestinal fluid were significantly (p < 0.05) increased in case of APL fed mice. Further, feeding of APL also demonstrated a positive effect on different haematological parameters viz. Hb (gm %), RBC and WBC count. The results indicated the immunoprotective effects of APL against Shigella dysenteriae induced infection in mice.

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BACKGROUND: The Loewenstein-Acevedo Scale for Semantic Interference and Learning (LASSI-L) is a novel cognitive test that measures recovery from proactive semantic interference, which may be an early cognitive marker of Alzheimer's disease (AD). OBJECTIVE: To generate normative data for a Spaniard population and to validate the LASSI-L for the diagnosis of amnestic mild cognitive impairment (aMCI) and mild AD. METHODS: We performed a cross-sectional study in which 97 healthy participants, 34 with aMCI, and 33 with mild AD were studied with LASSI-L and a comprehensive neuropsychological protocol. The overlapping strategy analysis was used to maximize the sample size and to provide age- and education-adjusted normative data using a logistic regression analysis. RESULTS: Internal consistency was 0.932. Convergent validity with the Free and Cued Selective Reminding Test was moderate. LASSI-L raw scores were correlated with age and years of education, but not gender. The area under the curve for discriminating between healthy controls and aMCI was 0.909, and between healthy controls and mild AD was 0.986. LASSI-L sub-scores representing maximum storage capacity, recovery from proactive interference, and delayed recall yielded the highest diagnostic accuracy. CONCLUSIONS: The LASSI-L is a reliable and valid test for the diagnosis of aMCI and mild AD. The age and education influences on the performance of the test and normative data are provided. LASSI-L merits further studies to evaluate its ability to detect preclinical AD and predict progression to aMCI and early dementia.

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INTRODUCTION: Probiotics are live microorganisms which when administered in adequate amounts confer a health benefit on the host. Sufficient calcium intake has been reported to support bone growth and prevent bone loss during the ageing process. AIM: To determine the effect of Lactobacillus helveticus MTCC 5463 probiotic dietary intervention on serum calcium & haematological parameters in geriatric population. MATERIALS AND METHODS: Healthy volunteers with age ranging from 64-74 years were recruited from the nearby residential areas in and around Anand, Gujarat. Study duration was from 2012 to 2015. Of the 112 subjects initially enrolled in the trial, 36 withdrew before the intervention because of not matching with criterias. Of the 76 participants, 5 subjects (4%) under test group and 12 subjects (11%) under placebo left the study. We had 59 subjects who successfully completed a double blind cross over trial. Probiotic fermented milk products (in form of "Lassi") was prepared by supplementing toned milk with honey and fermenting with probiotic Lactobacillus helveticus MTCC 5463 and Streptococcus thermophilus MTCC 5460. The final product had at least 10(8) CFU/ml of viable Lactobacillus helveticus MTCC 5463 at the time of feeding. During feeding period, 200 ml of fermented product containing the test strain to one group and a similar product but without the test strain as placebo were fed regularly at the time of breakfast in morning for 4 weeks. Subjects of each group were given a washout period of 4 weeks before they were crossed over and included to the other group. The study was approved by institutional ethics committee. RESULTS: The socio-demographic and clinical profiles were similar at baseline. The mean (SD) calcium level improved significantly in test {9.36 (0.45) vs 8.45 (0.61), p<0.001}. No significant effect was observed with respect to haemoglobin & haematological parameters. CONCLUSION: The well-documented probiotic Lactobacillus helveticus MTCC 5463 confirmed increase in serum calcium level but no effect on haematological parameters when administered to geriatrics.

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OBJECTIVE: To examine the utility of a novel "cognitive stress test" to detect subtle cognitive impairments and amyloid load within the brains of neuropsychologically normal community-dwelling elders. METHODS: Participants diagnosed as cognitively normal (CN), subjective memory impairment (SMI), mild cognitive impairment (MCI), and preclinical mild cognitive impairment (PreMCI) were administered the Loewenstein-Acevedo Scale for Semantic Interference and Learning (LASSI-L), a sensitive test of proactive semantic interference (PSI), retroactive semantic interference, and, uniquely, the ability to recover from the effects of PSI. Ninety-three subjects (31 men and 62 women) were recruited from three academic institutions in a research consortium. A subset of these individuals underwent 18F florbetapir positron emission tomography scanning. Relative percentages of impairment for each diagnostic group on the LASSI-L were calculated by χ(2) and Fisher's exact tests. Spearman's rho was used to examine associations between amyloid load and different cognitive measures. RESULTS: LASSI-L deficits were identified among 89% of those with MCI, 47% with PreMCI, 33% with SMI, and 13% classified as CN. CN subjects had no difficulties with recovery from PSI, whereas SMI, preMCI, and MCI participants evidenced deficits in recovery from PSI effects. Among a subgroup of participants with normal scores on traditional neuropsychological tests, the strong associations were between the failure to recover from the effects of PSI and amyloid load in the brain. CONCLUSION: Failure to recover or compensate for the effects of PSI on the LASSI-L distinguishes the LASSI-L from other widely used neuropsychological tests and appears to be sensitive to subtle cognitive impairments and increasing amyloid load.

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Studies were conducted to extend the shelf life of sorghum based fermented milk beverage (referred to SSL) developed at our Institute. In the first approach preservatives namely nisin (N) @ 400RU/ml, MicroGARD (M) @ (1%), potassium sorbate (PS) @ (0.15%) were added to the beverage before packaging and in the second approach thermization (65 °C/5 min) of the packaged samples containing above mentioned preservatives was adopted. The shelf life was assessed on the basis of sensory, physico-chemical and microbiological parameters. Total plate count and lactic acid bacterial count increased till 7th day of storage and afterwards decreased significantly (p < 0.01). Yeasts and molds count increased significantly (p < 0.01) throughout the storage period and the rate of increase was lowest in samples containing PS. Samples containing PS, N and M were found sensorily acceptable up to 35, 28 and 21 days, respectively. Though the thermization treatment helped in improving the microbiological and chemical quality of the beverage, the sensory and physical quality was adversely affected. Addition of PS without thermization was found to be the best preservation technique for enhancing the shelf life of SSL at refrigeration conditions.

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A solid phase extraction method using C18 cartridges was standardized for the isolation of multiple sweeteners (aspartame, acesulfame-K and saccharin) and their degradation products (diketopiperazine, Lphenylalanine, acetoacetamide and 2-sulfobenzoic acid) from lassi. Analytical conditions for HPLC were standardized over C18 column using UV detector for the simultaneous separation and estimation of multiple sweeteners and their degradation products in lassi sample isolates. A simple cartridge free method was developed for the isolation of sucralose from lassi. Method was also standardized for qualitative detection and quantitative estimation of sucralose over amino and silica gel plates of HPTLC.