Tuning Dimensions of Complexes through Selective In Situ Reaction, Mechanistic Insights into Ni(II)-Catalyzed Br-OH Exchange, Magnetic Properties, and Density Functional Theory Studies.

Two coordination polymers (CPs), namely, [Mn3(L)2(4,4'-bipy)2(H2O)2]n (1) and [Ni(L1)(1,4-bib)(H2O)]n (2) (H3L = 5-(3-bromo-4-carboxyphenoxy)isophthalic acid, H2L1 = 5-(3-hydroxyphenoxy)isophthalic acid, 4,4'-bpy = 4,4'-bipyridine, and 1,4-bib = 1,4-bis(1H-imidazol-1-yl)benzene), were synthesized under hydrothermal conditions. Most notably, with the help of the bromine atom-inducing effect, ligand transformation was observed in the structure of complex 2, which was scrutinized thoroughly by single crystal X-ray crystallography and X-ray photoelectron spectroscopy (XPS). Strikingly, Ni(II) ions were utilized as both coordinated atoms and as a catalyst for in situ Br-OH exchange of H3L in the process, as a result of which the product would have preferred to form a one-dimensional chain. The same reaction cannot happen in 1, leading to form a two-dimensional structure. Moreover, Ni(II)-catalyzed and magnetic exchange mechanisms were well interpreted using density functional theory (DFT) calculations. Finally, complexes 1-2 show three-dimensional (3D) supramolecular structures because of intermolecular weak interactions (C-Br···π, C-H···π, C-H···O, and π···π stacking) and exhibit utterly different antiferrimagnetic coupling interactions.

Validation of the Chinese version of Addenbrooke's cognitive examination III for detecting mild cognitive impairment.

OBJECTIVES: To evaluate the reliability and validity of Chinese version of Addenbrooke's Cognitive Examination III (ACE-III-CV) in the identification of mild cognitive impairment (MCI), and further investigate the optimal cutoff scores according to different age and education level. METHOD: A total of 716 individuals aged from 50 to 90 years old were recruited through internet-based and print advertisements, including 431 cognitively normal controls (NC) and 285 individuals with MCI according to an actuarial neuropsychological method put forward by Jak and Bondi. Besides the cognitive screening tests of ACE-III-CV, Mini-Mental State Examination (MMSE) and Chinese version of Montreal Cognitive Assessment-Basic (MoCA-BC), all the participants underwent a battery of standardized neuropsychological tests. Validations of the ACE-III-CV, MMSE, and MoCA-BC for detecting MCI from NC were determined by Receiver operating characteristic (ROC) curves. RESULTS: ACE-III-CV had a good reliability (Cronbach's coefficient α = 0.807, intraclass correlation coefficients for interrater and test-retest reliability were 0.95 and 0.93). According to the area under ROC curve (AUC), ACE-III-CV and MoCA-BC showed better ability than MMSE in detecting MCI. No significant difference was found between ACE-III-CV and MoCA-BC. The optimal cutoff scores of ACE-III-CV for screening MCI were 72 for individuals with 1-9 years of education, 78 for individuals with 10-15 years of education, and 80 for individuals with more than 16 years of education. CONCLUSION: The Chinese version of ACE-III-CV is a reliable and valid screening tool for detecting MCI. The optimal cutoff scores are closely related with education level.

A comparative study on the validations of three cognitive screening tests in identifying subtle cognitive decline.

BACKGROUND: Subtle cognitive decline (SCD) may represent a very early stage of objective cognitive impairment before mild cognitive impairment (MCI), with less neuronal damage and more functional reservation. Detecting individuals with SCD is imperative for dementia prevention and treatment. In this study, we aimed to compare the validations of three cognitive screening tests, Mini-Mental State Examination (MMSE), Montreal Cognitive Assessment-Chinese Version (MoCA-CV), and Memory and Executive Screening (MES), in identifying subtle cognitive decline. METHODS: A total of 407 individuals were recruited, including 147 cognitively normal controls (NC), 102 individuals with subtle cognitive decline (SCD) and 158 individuals with mild cognitive impairment (MCI) according to the operational neuropsychological criteria proposed by Jak and Bondi's. All participants underwent standardized comprehensive neuropsychological tests and the three cognitive screening tests. Chi-square analysis was used to compare the cognitive performance among the groups of NC, SCD and MCI. Receiver operating characteristic (ROC) curves were used to evaluate the abilities of MMSE, MoCA-CV and MES in discriminating NC, SCD and MCI. RESULTS: Compared with NC, SCD showed a significant decline only in the tests of memory, such as Auditory Verbal Learning Test (AVLT), Rey-Osterrieth Complex Figure Test (CFT) and Prospective Memory Test (PrM) (P < 0.01). However, MCI showed significant decline in all cognitive performances (P < 0.01). The scores of MMSE, MoCA-CV and MES all showed a progressive downward trend within the groups of NC, SCD and MCI (P < 0.001). In ROC Analyses for discriminating individuals with SCD from NC, the most appropriate MES cutoff was 84, with a sensitivity of 74.3%, a specificity of 60.8% and 0.738 for AUC (95%CI, 0.675-0.801). By contrast, MMSE and MOCA-CV had poor sensitivity (67.4 and 70.8%, respectively) and specificity (51.0 and 52.9%, respectively), and smaller AUCs (0.643 and 0.644, respectively) than the MES. CONCLUSION: As a screening test, MES is more efficacious in identifying SCD from normal controls than MMSE and MoCA-CV.

Carotid plague formation is associated with ankle-brachial index in elderly people.

AIMS: This study aimed at examining whether ankle-brachial index (ABI) and brachial-ankle pulse wave velocity (baPWV) were independently associated with carotid Intima-media thickness (CIMT) or carotid artery plaque (CAP) in elderly people. METHODS: A cross-sectional analysis was performed in 155 individuals aged over 75 years who underwent the measurements of ABI and baPWV. Low ABI was defined as ABI ≤ 1.0. High baPWV was defined as baPWV > 2000 cm/s. The CIMT and CAP were measured with a B-mode tomographic ultrasound system. RESULTS: Neither ABI nor baPWV was associated with CIMT in this elderly population. The group with low ABI (≤ 1.0) was significantly associated with a higher prevalence of carotid plaque (P = 0.001), while the relationship between baPWV and prevalence of carotid plaque was not found. Linear regression analysis showed that the value of ABI was significantly associated with the thickness of carotid plaque. Even in the full adjusted model, each 0.01unit ABI decreasing still increased 0.1663 mm of carotid plaque thickness (P = 0.004). Logistic Regression Analysis demonstrated that ABI lower than 1.0 had predictive value in the formation of carotid plaque with top quartile thickness (OR 2.834, 95% CI 1.131-7.099, P = 0.026). Furthermore, individuals with low ABI (≤ 1.0) were more likely to form hypoechoic carotid plaques according to ultrasonography. CONCLUSION: Low ABI but not high baPWV was associated with the formation of carotid plaque. Furthermore, ABI was significantly associated with the thickness and morphology of carotid plaque in elderly people.

Erythrocyte rheological properties but not whole blood and plasma viscosity are associated with severity of hypertension in older people.

OBJECTIVE: This study was carried out to determine whether changes in hemorheological parameters parallel the severity of essential hypertension. METHODS: A total of 198 older hypertensive patients were recruited and classified into 3 stages of hypertension according to the grading standard of hypertension. The whole blood viscosity (WBV) at various shear rates, plasma viscosity and erythrocyte rheology (including erythrocyte rigidity index, erythrocyte aggregation index and erythrocyte deformation index) were examined. RESULTS: Erythrocyte rheology paralleled the severity of essential hypertension and was significantly correlated to the average 24 h systolic blood pressure and diastolic blood pressure. Logistic analysis revealed that erythrocyte rigidity and the erythrocyte aggregation index were positively correlated with the severity of hypertension, while the erythrocyte deformation index was negatively correlated. No association was found between WBV, plasma viscosity and the severity of hypertension. CONCLUSION: The rheological properties of erythrocyte viscosity were correlated with the severity of hypertension in older people but the WBV and plasma viscosity were not.

Organocatalytic asymmetric Michael addition of aliphatic aldehydes to indolylnitroalkenes: access to contiguous stereogenic tryptamine precursors.

Because of the importance of the indole framework and the versatile transformation of nitro and formyl groups, the efficient synthesis of optically pure 2-alkyl-3-(1H-indol-3-yl)-4-nitrobutanals, one type of tryptamine precursors are of great interest for pharmaceutical and biological research. Herein, the Michael addition of aliphatic aldehydes to indolylnitroalkenes has been developed using (S)-diphenylprolinol trimethylsilyl ether as an organocatalyst, which provides the desired optically pure syn 2-alkyl-3-(1H-indol-3-yl)-4-nitrobutanal derivatives in up to 98% yield with up to >99:1 dr and >99% ee. To show the synthetic usefulness of this methodology, optically active 2-alkyl-4-nitro-3-(1-tosyl-1H-indol-3-yl)butan-1-ol and tryptamine derivatives are readily obtained by stepwise systematic transformations.

The Value of Clock Drawing Process Assessment in Screening for Mild Cognitive Impairment and Alzheimer's Dementia.

Many clock drawing test (CDT) scoring systems focus on drawing results and lack drawing process assessments. This study created a CDT scoring procedure with drawing process assessment and explored its diagnostic value in screening for mild cognitive impairment (MCI) and early Alzheimer's disease (AD) from normal control (NC). We used logistic regression and receiver operating characteristic (ROC) curves to determine a new, sensitive scoring system for AD and MCI patients in a derivation cohort. The new scoring method was then compared to two common scoring systems and externally validated in a second cohort. We developed a new scoring system named CDT5, which contained one process assessment item: remember setting time without asking. Compared with two published scoring systems, CDT5 had better discriminatory power in distinguishing AD patients from NCs in derivation (area under the ROC curve [area under the curve, AUC] = .890) and validation (AUC = .867) cohorts. Three scoring systems had poor diagnostic accuracy at discriminating MCI patients from controls, with CDT5 being the most sensitive (78.57%). Adding the drawing process in CDT helps accurately detect patients with early AD, but its role in identifying patients with MCI needs to be further explored.

Analysis of the relationship between blood pressure variability and subtle cognitive decline in older adults.

BACKGROUND: Blood pressure variability (BPV) has been shown to be related to mild cognitive impairment and Alzheimer's disease in a number of studies. However, the relationship between BPV and subtle cognitive decline (SCD) has received minimal attention in this field of research to date and has rarely been reported. AIM: To examine whether SCD is independently associated with changes in BPV in older adults. METHODS: Participants were selected based on having participated in cognitive function evaluation and ambulatory blood pressure measurement at the Shanghai Sixth People's Hospital Affiliated with Shanghai Jiao Tong University School of Medicine between June 2020 and August 2022. The participants included 182 individuals with SCD as the experimental group and 237 with normal cognitive function as the control group. The basic data, laboratory examinations, scale tests, and ambulatory blood pressure test results of the two groups were analyzed retrospectively, and the relationship between SCD and BPV was subsequently evaluated. RESULTS: Significant differences were observed between the two groups of participants (P < 0.05) in terms of age, education level, prevalence rate of diabetes, fasting blood glucose level, 24-h systolic blood pressure standard deviation and coefficient of variation, 24-h diastolic blood pressure standard deviation and coefficient of variation. The scale monitoring results showed significant differences in the scores for memory, attention, and visual space between the experimental and control groups. Logistic regression analysis indicated that age, education level, blood sugar level, and BPV were factors influencing cognitive decline. Linear regression analysis showed that there was an independent correlation between blood pressure variation and SCD, even after adjusting for related factors. Each of the above differences was still significant. CONCLUSION: This study suggests that increased BPV is associated with SCD.

Validation of a modified Chinese version of Mini-Addenbrooke's Cognitive Examination for detecting mild cognitive impairment.

BACKGROUND: For detecting mild cognitive impairment (MCI), brief cognitive screening tools are increasingly required for the advantage of time saving and no need for special equipment or trained raters. We aimed to develop a modified Chinese version of Mini-Addenbrooke's Cognitive Examination (C-MACE) and further evaluate its validation in detecting MCI. METHODS: A total of 716 individuals aged from 50 to 90 years old were recruited, including 431 cognitively normal controls (NC) and 285 individuals with MCI. The effect size of Cramer's V was used to explore which items in the Chinese version of Addenbrooke's Cognitive Examination-III (ACE-III-CV) best associated with MCI and to form the C-MACE. Receiver operating characteristic (ROC) analyses were carried out to explore the ability of C-MACE, ACE-III-CV, Chinese version of Montreal Cognitive Assessment-Basic (MoCA-BC), and Mini-Mental State Examination (MMSE) in discriminating MCI from NC. RESULTS: Five items with greatest effect sizes of Cramer's V were selected from ACE-III-CV to form the C-MACE: Memory Immediate Recall, Memory Delayed Recall, Memory Recognition, Verbal Fluency Animal and Language Naming. With a total score of 38, the C-MACE had a satisfactory classification accuracy in detecting MCI (area under the ROC curve, AUC = 0.892), superior to MMSE (AUC = 0.782) and comparable to ACE-III-CV (AUC = 0.901) and MoCA-BC (AUC = 0.916). In the subgroup of Age > 70 years, Education ≤ 12 years, the C-MACE got a highest classification accuracy (AUC = 0.958) for detecting MCI. CONCLUSION: In the Chinese-speaking population, C-MACE derived from ACE-III-CV may identify MCI with a good classification accuracy, especially in aged people with low education.

Altered metamemory precedes cognitive impairment in subjective cognitive decline with positive amyloid-beta.

Subjective cognitive decline (SCD) as an indicator of preclinical Alzheimer's disease (AD) may precede mild cognitive impairment (MCI) over several decades. Self-reported cognitive decline as a typical clinical manifestation is critical in preclinical AD. Metacognition represents a person's ability to accurately assess cognition. Our study aimed to examine (1) the alternations of metamemory in a cohort across the Alzheimer's continuum, (2) the association between metamemory and cognition, and (3) the relationship of cortical thickness in four regions of interest (ROI) with metamemory scores. Six hundred ninety-seven participants were classified as 79 AD dementia, 161 aMCI, 261 SCD, and 196 cognitively unimpaired (CU) individuals, in which 418 participants aged above 65, 131 participants with Aß+ after receiving positron emission tomography, and 602 participants received sMRI. The degree of confidence (DOC) was measured by calculating discrepancies between judgments and memory performance. We assessed the relationships between DOC tertiles and cognition and analyzed the screening power, then investigated the partial correlation between DOC and ROIs, controlled by age, sex, and cognition. In the Aß+ subgroup, SCD showed significantly higher DOC scores than the CU group. There was an increasing trend of overconfidence with the decline of cognition across the AD spectrum (P for trend < 0.001). After adjusting for age, sex, and education, the lower degree of confidence-long-term delay recall (DOC-LD) tertiles were associated with lower odds ratio in SCD, aMCI, and AD in the Aß+ subgroup (all P for trend < 0.05). The area under the curves of DOC scores for screening SCD from CU in the Aß+ subgroup was better than that in all participants and the age ≥65 subgroup. Partial correlation showed that in the Aß+ subgroup, DOC-SD (degree of confidence-short-term delay recall) was negatively correlated with the anterior cingulate cortex; DOC-LD was negatively correlated with the cortices of parahippocampal, anterior cingulate, posterior cingulate, and medial orbitofrontal. In individuals with Aß+, SCD exhibited a detectable metamemory alternation before objective cognitive impairment could be tested, indicated by the overestimation in the memory performance. The pattern of an increasing trend of overconfidence across SCD, aMCI, and AD dementia supports the view of a continuum in Alzheimer's disease.

Non-linear Character of Plasma Amyloid Beta Over the Course of Cognitive Decline in Alzheimer's Continuum.

Plasma amyloid-ß (Aß) was associated with brain Aß deposition and Alzheimer's disease (AD) development. However, changes of plasma Aß over the course of cognitive decline in the Alzheimer's continuum remained uncertain. We recruited 449 participants to this study, including normal controls (NC), subjective cognitive decline (SCD), mild cognitive impairment (MCI), AD, and non-AD dementia. All the participants underwent plasma Aß42, Aß40, and t-tau measurements with single-molecule array (Simoa) immunoassay and PET scan with 18F-florbetapir amyloid tracer. In the subgroup of Aß-PET positive, plasma Aß42 and Aß42/Aß40 ratio was significantly lower in AD than NC, SCD and MCI, yet SCD had significantly higher levels of plasma Aß42 than both NC and MCI. In the diagnostic groups of MCI and dementia, participants with Aß-PET positive had lower plasma Aß42 and Aß42/40 ratio than participants with Aß-PET negative, and the increasing levels of plasma Aß42 and Aß42/40 ratio indicated lower risks of Aß-PET positive. However, in the participants with SCD, plasma Aß42 and Aß40 were higher in the subgroup of Aß-PET positive than Aß-PET negative, and the increasing levels of plasma Aß42 and Aß40 indicated higher risks of Aß-PET positive. No significant association was observed between plasma Aß and Aß-PET status in normal controls. These findings showed that, in the continuum of AD, plasma Aß42 had a significantly increasing trend from NC to SCD before decreasing in MCI and AD. Furthermore, the predictive values of plasma Aß for brain amyloid deposition were inconsistent over the course of cognitive decline.

Enones from Acid Fluorides and Vinyl Triflates by Reductive Nickel Catalysis.

A nickel-catalyzed reductive coupling between acid fluorides and vinyl triflates has been described. This method provides an efficient access to various enones and avoids the requirement for acyl or vinyl metallic reagents in the conventional approaches. The reaction proceeds with a broad range of acid fluorides and cyclic vinyl triflates, tolerating several functional groups. The utility of this synthetic method has been demonstrated by the late-stage modification of pharmaceuticals and biologically active natural compounds.