Predictive Modeling Using a Composite Index of Sleep and Cognition in the Alzheimer's Continuum: A Decade-Long Historical Cohort Study.

Background: Sleep disturbances frequently affect Alzheimer's disease (AD), with up to 65% patients reporting sleep-related issues that may manifest up to a decade before AD symptoms. Objective: To construct a nomogram that synthesizes sleep quality and cognitive performance for predicting cognitive impairment (CI) conversion outcomes. Methods: Using scores from three well-established sleep assessment tools, Pittsburg Sleep Quality Index, REM Sleep Behavior Disorder Screening Questionnaire, and Epworth Sleepiness Scale, we created the Sleep Composite Index (SCI), providing a comprehensive snapshot of an individual's sleep status. Initially, a CI conversion prediction model was formed via COX regression, fine-tuned by bidirectional elimination. Subsequently, an optimized prediction model through COX regression, depicted as a nomogram, offering predictions for CI development in 5, 8, and 12 years among cognitively unimpaired (CU) individuals. Results: After excluding CI patients at baseline, our study included 816 participants with complete baseline and follow-up data. The CU group had a mean age of 66.1±6.7 years, with 36.37% males, while the CI group had an average age of 70.3±9.0 years, with 39.20% males. The final model incorporated glial fibrillary acidic protein, Verbal Fluency Test and SCI, and an AUC of 0.8773 (0.792-0.963). Conclusions: In conclusion, the sleep-cognition nomogram we developed could successfully predict the risk of converting to CI in elderly participants and could potentially guide the design of interventions for rehabilitation and/or cognitive enhancement to improve the living quality for healthy older adults, detect at-risk individuals, and even slow down the progression of AD.

Innovative Multivariable Model Combining MRI Radiomics and Plasma Indexes Predicts Alzheimer's Disease Conversion: Evidence from a 2-Cohort Longitudinal Study.

To explore the complementary relationship between magnetic resonance imaging (MRI) radiomic and plasma biomarkers in the early diagnosis and conversion prediction of Alzheimer's disease (AD), our study aims to develop an innovative multivariable prediction model that integrates those two for predicting conversion results in AD. This longitudinal multicentric cohort study included 2 independent cohorts: the Sino Longitudinal Study on Cognitive Decline (SILCODE) project and the Alzheimer Disease Neuroimaging Initiative (ADNI). We collected comprehensive assessments, MRI, plasma samples, and amyloid positron emission tomography data. A multivariable logistic regression analysis was applied to combine plasma and MRI radiomics biomarkers and generate a new composite indicator. The optimal model's performance and generalizability were assessed across populations in 2 cross-racial cohorts. A total of 897 subjects were included, including 635 from the SILCODE cohort (mean [SD] age, 64.93 [6.78] years; 343 [63%] female) and 262 from the ADNI cohort (mean [SD] age, 73.96 [7.06] years; 140 [53%] female). The area under the receiver operating characteristic curve of the optimal model was 0.9414 and 0.8979 in the training and validation dataset, respectively. A calibration analysis displayed excellent consistency between the prognosis and actual observation. The findings of the present study provide a valuable diagnostic tool for identifying at-risk individuals for AD and highlight the pivotal role of the radiomic biomarker. Importantly, built upon data-driven analyses commonly seen in previous radiomics studies, our research delves into AD pathology to further elucidate the underlying reasons behind the robust predictive performance of the MRI radiomic predictor.

Pathophysiology characterization of Alzheimer's disease in South China's aging population: for the Greater-Bay-Area Healthy Aging Brain Study (GHABS).

INTRODUCTION: The Guangdong-Hong Kong-Macao Greater-Bay-Area of South China has an 86 million population and faces a significant challenge of Alzheimer's disease (AD). However, the characteristics and prevalence of AD in this area are still unclear due to the rarely available community-based neuroimaging AD cohort. METHODS: Following the standard protocols of the Alzheimer's Disease Neuroimaging Initiative, the Greater-Bay-Area Healthy Aging Brain Study (GHABS) was initiated in 2021. GHABS participants completed clinical assessments, plasma biomarkers, genotyping, magnetic resonance imaging (MRI), ß-amyloid (Aß) positron emission tomography (PET) imaging, and tau PET imaging. The GHABS cohort focuses on pathophysiology characterization and early AD detection in the Guangdong-Hong Kong-Macao Greater Bay Area. In this study, we analyzed plasma Aß42/Aß40 (A), p-Tau181 (T), neurofilament light, and GFAP by Simoa in 470 Chinese older adults, and 301, 195, and 70 had MRI, Aß PET, and tau PET, respectively. Plasma biomarkers, Aß PET, tau PET, hippocampal volume, and temporal-metaROI cortical thickness were compared between normal control (NC), subjective cognitive decline (SCD), mild cognitive impairment (MCI), and dementia groups, controlling for age, sex, and APOE-ε4. The prevalence of plasma A/T profiles and Aß PET positivity were also determined in different diagnostic groups. RESULTS: The aims, study design, data collection, and potential applications of GHABS are summarized. SCD individuals had significantly higher plasma p-Tau181 and plasma GFAP than the NC individuals. MCI and dementia patients showed more abnormal changes in all the plasma and neuroimaging biomarkers than NC and SCD individuals. The frequencies of plasma A+/T+ (NC; 5.9%, SCD: 8.2%, MCI: 25.3%, dementia: 64.9%) and Aß PET positivity (NC: 25.6%, SCD: 22.5%, MCI: 47.7%, dementia: 89.3%) were reported. DISCUSSION: The GHABS cohort may provide helpful guidance toward designing standard AD community cohorts in South China. This study, for the first time, reported the pathophysiology characterization of plasma biomarkers, Aß PET, tau PET, hippocampal atrophy, and AD-signature cortical thinning, as well as the prevalence of Aß PET positivity in the Guangdong-Hong Kong-Macao Greater Bay Area of China. These findings provide novel insights into understanding the characteristics of abnormal AD pathological changes in South China's older population.

Vanmaneniamarmorata, a new species of loach (Teleostei: Gastromyzontidae) from the middle Chang-Jiang Basin in Guizhou Province, south China.

BACKGROUND: The gastromyzontid genus Vanmanenia was established by Hora in 1932, based on the type species Vanmaneniastenosoma. The genus is a loach group adapted to running waters of streams from southern China, northern Vietnam and Laos. Currently, 19 valid species of the genus have been recognised. The northernmost distribution of the genus is the Yangtze River (= Chang-Jiang in Chinese) Basin and five species (V.maculata, V.intermedia, V.stenosoma, V.pseudostriata and V.gymnetrus) have been reported from the Basin. NEW INFORMATION: Vanmaneniamarmorata, a new hillstream species of loach, is here described from the middle Chang-Jiang Basin in Guizhou Province, south China. It is distinguished from its congeners by having a combination of the following characters: three triangular-shaped rostral lobules; postdorsal saddles wider than interspaces; a more backwards-placed anus (the vent to anal distance 30.5-36.9% of the pelvic to anal distance); a larger gill opening with its upper extremity reaching the level of the middle of the orbit; anal-fin base length 5.6-6.4% of SL; caudal-peduncle length 11.6-12.9% of SL; prepelvic length 51.1-53.4% of SL. Its validity is also affirmed by its distinct cyt b gene sequence divergence with all sampled congeners and its monophyly recovered in a cyt b gene-based phylogenetic analysis.

Complete mitochondrial genome of Vanmanenia hainanensis (Cypriniformes: Gastromyzontidae).

Vanmanenia hainanensis Chen & Zheng 1980 is endemic to Hainan Island, China. The complete mitogenome of the species was sequenced in this study. It was 16,555 bp in length, containing 13 protein-coding genes (PCGs), 22 tRNA genes, 2 rRNA genes, and 1 control region. The base composition was 29.5% A, 25.4% T, 16.7% G, and 28.4% C. All genes were encoded on the H-strand except for ND6 and 8 tRNA genes, located on the l-strand. Phylogenetic analysis based on 13 protein-coding genes indicated that the genus Vanmanenia did not form monophyly and it had the closest relationship with Formosania. This study aimed at providing useful genetic information for future studies on taxonomy, phylogeny, and evolution of Vanmanenia species.

The complete mitogenome of Liniparhomaloptera qiongzhongensis (Cypriniformes: Gastromyzontidae) and phylogenetic implications.

Liniparhomaloptera qiongzhongensis Zheng and Chen 1980 is distributed in Hainan Island, China. The complete mitogenome of the species was sequenced in this study. It had a circular molecule of 16,554 bp in length with a total of 56.5% A + T content, containing 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and one control region. Five overlapping regions and 14 intergenic sequences were observed with the length of 2-10 bp and 1-31 bp, respectively. The phylogenetic analysis based on 13 protein-coding genes revealed that L. qiongzhongensis had the closest relationship with L. disparis. This study would provide useful genetic information for future studies on taxonomy, phylogeny and evolution of Liniparhomaloptera species.

Vanmanenia intermedia Fang, 1935, a valid hill-stream species of loach (Teleostei: Gastromyzontidae) from the middle Yangtze River basin, Southwest China.

Vanmanenia intermedia, which has long been synonymized with V. pingchowensis since 1980, is here revalidated using morphological characters and molecular evidences, and redescribed on the basis of topotypic specimens. This species is distinguished from all other congeneric species by the following combination of characters: triangular-shaped rostral lobules without secondary rostral barbels; distal edge of dorsal-fin slightly concave; no longitudinal black stripe on the flank; a longer snout (length 52.6-64.5 % of HL); a more backwards-placed anus (the vent to anal distance 34.7-46.1% of the pelvic to anal distance); a slender caudal peduncle (depth 9.1-11.3 % of SL); a longer anal-fin base (length 7.5-9.5 % of SL); and a smaller gill opening with its upper extremity closer to the level of the lower margin of the orbit. The validity of V. intermedia is also confirmed by its significant cyt b gene sequence divergence with all sampled congeneric species and its monophyly recovered in the cyt b gene-based phylogenetic analysis.

Garra dengba, a new species of cyprinid fish (Pisces: Teleostei) from eastern Tibet, China.

Garra dengba is here described from the Chayu-Qu, a tributary flowing into the Brahmaputra River, in Chayu County, eastern Tibet, China. It shares the presence of an incipient proboscis on the snout with G. arupi, G. elongata, G. gravelyi, G. kalpangi, and G. rotundinasus, but is distinguished from these five species in having, among other features, fewer branched dorsal- and anal-fin rays and more perforated lateral-line scales. Its validity was also confirmed by a molecular phylogenetic analysis based on the cytochrome b gene.

Speolabeo hokhanhi, a new cavefish from Central Vietnam (Teleostei: Cyprinidae).

Speolabeo hokhanhi, new species, is here described from Hang Va Cave in Phong Nha-Ke Bang National Park (Son River basin) in Central Vietnam. It can be distinguished from S. musaei by having no papillae on the lower lip, no hump immediately behind the head, a duckbilled snout, a shorter caudal peduncle (length 16.8-18.6% SL), and the pelvic fin inserted closer to the snout tip than to the caudal-fin base.