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Although the hippocampus is one of the most studied structures in the human brain, limited quantitative data exist on its 3D organization, anatomical variability, and effects of disease on its subregions. Histological studies provide restricted reference information due to their 2D nature. In this paper, high-resolution (∼200 × 200 × 200 μm) ex vivo MRI scans of 31 human hippocampal specimens are combined using a groupwise diffeomorphic registration approach into a 3D probabilistic atlas that captures average anatomy and anatomic variability of hippocampal subfields. Serial histological imaging in 9 of the 31 specimens was used to label hippocampal subfields in the atlas based on cytoarchitecture. Specimens were obtained from autopsies in patients with a clinical diagnosis of Alzheimer's disease (AD; 9 subjects, 13 hemispheres), of other dementia (nine subjects, nine hemispheres), and in subjects without dementia (seven subjects, nine hemispheres), and morphometric analysis was performed in atlas space to measure effects of age and AD on hippocampal subfields. Disproportional involvement of the cornu ammonis (CA) 1 subfield and stratum radiatum lacunosum moleculare was found in AD, with lesser involvement of the dentate gyrus and CA2/3 subfields. An association with age was found for the dentate gyrus and, to a lesser extent, for CA1. Three-dimensional patterns of variability and disease and aging effects discovered via the ex vivo hippocampus atlas provide information highly relevant to the active field of in vivo hippocampal subfield imaging.

Tau protein neurofibrillary tangles are closely linked to neuronal/synaptic loss and cognitive decline in Alzheimer’s disease and related dementias. Our knowledge of the pattern of neurofibrillary tangle progression in the human brain, critical to the development of imaging biomarkers and interpretation of in vivo imaging studies in Alzheimer’s disease, is based on conventional two-dimensional histology studies that only sample the brain sparsely. To address this limitation, ex vivo MRI and dense serial histological imaging in 18 human medial temporal lobe specimens (age 75.3 ± 11.4 years, 45 to 93) were used to construct three-dimensional quantitative maps of neurofibrillary tangle burden in the medial temporal lobe at individual and group levels. Group-level maps were obtained in the space of an in vivo brain template, and neurofibrillary tangle was measured in specific anatomical regions defined in this template. Three-dimensional maps of neurofibrillary tangle burden reveal significant variation along the anterior-posterior axis. While early neurofibrillary tangle pathology is thought to be confined to the transentorhinal region, we find similar levels of burden in this region and other medial temporal lobe subregions, including amygdala, temporopolar cortex, and subiculum/cornu Ammonis 1 hippocampal subfields. Overall, the three-dimensional maps of neurofibrillary tangle burden presented here provide more complete information about the distribution of this neurodegenerative pathology in the region of the cortex where it first emerges in Alzheimer’s disease, and may help inform the field about the patterns of pathology spread, as well as support development and validation of neuroimaging biomarkers.

BackgroundHealthcare-associated infections (HAIs) and antimicrobial resistance (AMR) affect patients in acute-care hospitals worldwide. No systematic review has been published on adoption and implementation of the infection prevention and control (IPC) key components. The objective of this systematic review was to assess adoption and implementation of the three areas issued by the “National Health Commission of the People’s Republic of China” in acute-care hospitals in Mainland China, and to compare the findings with the key and core components on effective IPC, issued by the European Centre for Disease Prevention and Control (ECDC) and the World Health Organization (WHO).MethodsWe searched PubMed and the Chinese National Knowledge Infrastructure for reports on the areas “structure, organisation and management of IPC”, “education and training in IPC”, and “surveillance of outcome and process indicators in IPC” in acute-care facilities in Mainland China, published between January 2012 and October 2017. Results were stratified into primary care hospitals and secondary/tertiary care hospitals.ResultsA total of 6580 publications were retrieved, of which 56 were eligible for final analysis. Most of them were survey reports (n = 27), followed by observational studies (n = 17), and interventional studies (n = 12), either on hand hygiene promotion and best practice interventions (n = 7), or by applying education and training programmes (n = 5). More elements on IPC were reported by secondary/tertiary care hospitals than by primary care hospitals. Gaps were identified in the lack of detailing on organisation and management of IPC, education and training activities, and targets of surveillance such as central line-associated bloodstream infections, ventilator associated pneumonia, catheter-associated urinary tract infections, and Clostridium difficile infections. Information was available on adoption and implementation of 7 out of the 10 ECDC key components, and 7 out of the 8 WHO core components.ConclusionTo variable degrees, there is evidence on implementation of all NHCPRC areas and of most of the ECDC key components and the WHO core components in acute care hospitals in Mainland China. The results are encouraging, but gaps in effective IPC were identified that may be used to guide future national policy-making in Mainland China.Electronic supplementary materialThe online version of this article (10.1186/s13756-019-0481-y) contains supplementary material, which is available to authorized users.

OBJECTIVETo assess the prevalence of healthcare-associated infections (HAIs) in mainland China.DESIGNSystematic review and meta-analysis.SETTINGAdults and children from secondary and tertiary acute-care hospitals in mainland China.METHODSWe searched PubMed, the China National Knowledge Infrastructure, and Wan Fang for multicenter point-prevalence surveys of acute-care hospitals in mainland China from January 2006 to August 2016. All reports related to HAI, using a point-prevalence methodology and published either in English or Chinese were eligible.RESULTSIn total, 3,021 publications were identified; 115 were eligible for quality assessment and data abstraction. The weighted HAI prevalence (95% confidence interval [CI]) overall, in general hospitals, children's hospitals, maternal and child health hospitals, and oncology hospitals were 3.12% (95% CI, 2.94%-3.29%), 3.02% (95% CI, 2.79%-3.26%), 4.43% (95% CI, 3.39%-5.47%), 1.88% (95% CI, 1.47%-2.29%), and 3.96% (95% CI, 3.12%-4.79%), respectively. In general hospitals, prevalence was highest in adult intensive care units (26.07%; 95% CI, 23.03%-29.12%), followed by surgery (3.26%; 95% CI, 2.96%-3.57%), and internal medicine (3.06%; 95% CI, 2.67%-3.46%). Overall, lower respiratory tract infection was the most frequent HAI (24,185, 47.28%), followed by urinary tract infection (5,773, 11.29%) and upper respiratory tract infection (5,194, 10.15%). Gram-negative bacilli were the most frequently isolated pathogens, and Pseudomonas aeruginosa (3,395, 14.91%), and Escherichia coli (2,918, 12.82%) were the most common single microorganisms.CONCLUSIONSThis study is the largest systematic review on the prevalence of HAI in mainland China. These results provide a benchmark for future PPSs and a reference for infection prevention and control strategies in mainland China.Infect Control Hosp Epidemiol 2018;39:701-709.