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Aim: Inflammatory markers such as serum C‐reactive protein (CRP) are used as routine markers to detect anastomotic leakage following colorectal surgery. However, CRP is characterized by a relatively low predictive value, emphasizing the need for the development of novel diagnostic approaches. Volatile organic compounds (VOCs) are gaseous metabolic products deriving from all conceivable bodily excrements and reflect (alterations in) the patient's physical status. Therefore, VOCs are increasingly considered as potential non‐invasive diagnostic biomarkers. The aim of this study was to assess the diagnostic accuracy of urinary VOCs for colorectal anastomotic leakage. Methods: In this explorative multicentre study, urinary VOC profiles of 22 patients with confirmed anastomotic leakage and 27 uneventful control patients following colorectal surgery were analysed by field asymmetric ion mobility spectrometry (FAIMS). Results: Urinary VOCs of patients with anastomotic leakage could be distinguished from those of control patients with high accuracy: area under the receiver operating characteristics curve 0.91 (95% CI 0.81–1.00, P < 0.001), sensitivity 86% and specificity 93%. Serum CRP was significantly increased in patients with a confirmed anastomotic leak but with lower diagnostic accuracy compared to VOC analysis (area under the receiver operating characteristics curve 0.82, 95% CI 0.68–0.95, P < 0.001). Combining VOCs and CRP did not result in a significant improvement of the diagnostic performance compared to VOCs alone. Conclusion: Analysis by FAIMS allowed for discrimination between urinary VOC profiles of patients with a confirmed anastomotic leak and control patients following colorectal surgery. A superior accuracy compared to CRP and apparently high specificity was observed, underlining the potential as a non‐invasive biomarker for the detection of colorectal anastomotic leakage. [ABSTRACT FROM AUTHOR]

During surgery, a surgeon relies on the vision of his eyes and the touch of his hands. While laparoscopic surgery for colon cancer has proven to be safe and effective, it still remains a technically difficult procedure. Although it is associated with reduced haptic feedback, by enforcing the power of visual guidance, the loss of this feedback can be (partly) compensated for. Here we describe how the use of near-infrared dyes and fluorescence laparoscopy could help improve tumour staging and therefore lead to better selection of patients for postoperative adjuvant chemotherapy. More controversially, and analogous to melanoma and breast cancer surgery with sentinel node biopsy, we speculate that local resection with SLN harvesting in early colon cancer might change the therapeutic and surgical strategy in colon cancer. [ABSTRACT FROM AUTHOR]

OBJECTIVES: This study examines the correlation between actigraphic measures and a validated assessment scale of agitated behaviour in dementia, the Cohen-Mansfield Agitation Inventory (CMAI). METHODS: A total of 110 patients were included. Patients either suffered from Alzheimer dementia (AD), mixed dementia (MXD), frontotemporal dementia (FTD) or diffuse Lewy body disease (DLB). All patients underwent actigraphic recordings for 48 h. CMAI was scored by professional caretakers, who were responsible for the patient during his or her actigraphic recording. RESULTS: Patients with high total CMAI scores (>or= 50) clearly had higher levels of activity during the day as measured by means of actigraphy than patients with low total CMAI scores (ANOVA, F=126.75, p<0.0001). Patients with low MMSE scores (<20) also had higher activity levels during the day than patients with higher MMSE scores (ANOVA, F= 85.74, p<0.0001). Correlations between ctigraphic data and CMAI total scores were moderate but highly significant. CONCLUSION: We conclude that actigraphy is a useful tool to examine agitated behaviour in dementia. [ABSTRACT FROM AUTHOR]

Long considered to fluctuate between pro- and anti-inflammatory states, it has now become evident that microglia occupy a variegated phenotypic landscape with relevance to aging and neurodegeneration. However, whether specific microglial subsets converge in or contribute to both processes that eventually affect brain function is less clear. To investigate this, we analyzed microglial heterogeneity in a tauopathy mouse model (K18-seeded P301L) and an accelerated aging model (Senescence-Accelerated Mouse-Prone 8, SAMP8) using cellular indexing of transcriptomes and epitopes by sequencing. We found that widespread tau pathology in K18-seeded P301L mice caused a significant change in the number and morphology of microglia, but only a mild overrepresentation of disease-associated microglia. At the cell population-level, we observed a marked upregulation of the calprotectin-encoding genes S100a8 and S100a9. In 9-month-old SAMP8 mice, we identified a unique microglial subpopulation that showed partial similarity with the disease-associated microglia phenotype and was additionally characterized by a high expression of the same calprotectin gene set. Immunostaining for S100A8 revealed that this population was enriched in the hippocampus, correlating with the cognitive impairment observed in this model. However, incomplete colocalization between their residence and markers of neuronal loss suggests regional specificity. Importantly, S100A8-positive microglia were also retrieved in brain biopsies of human AD and tauopathy patients as well as in a biopsy of an aged individual without reported pathology. Thus, the emergence of S100A8-positive microglia portrays a conspicuous commonality between accelerated aging and tauopathy progression, which may have relevance for ensuing brain dysfunction., (© 2024 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.)

Over the past decade, clinical Alzheimer's disease research has been challenged with an increased interest in noncognitive symptomatology, commonly referred to as behavioural and psychological signs and symptoms of dementia (BPSD). In accordance, major attention is being paid to behavioural alterations in the phenotyping of transgenic mouse models. Besides an age-dependent decline of cognitive functions, the APP23 model was previously shown to exhibit cage activity disturbances, reminiscent of diurnal rhythm disturbances in Alzheimer patients. To further scrutinize these observations, circadian patterns of horizontal locomotor activity were assessed in 3-, 6- and 12-month-old APP23 mice and wild-type littermates in a test paradigm continuously recording cage activity over a period ranging from 1 to 3 days. At the age of 3 months, APP23 profiles resembled the wild-type pattern to a large extent, although minor differences were already noticeable. Six-month-old APP23 mice displayed an altered activity profile with a first indication of increased activity during the second half of the active phase, reminiscent of sundowning behaviour in Alzheimer patients. This bimodal overnight activity pattern became even more evident at the age of 12 months. The APP23 model was therefore shown to display an age-dependent development of cage activity disturbances and sundowning-like behaviour. A comparison is made with actigraphic recordings of human Alzheimer patients exhibiting sundowning behaviour. This first report of diurnal rhythm disturbances and sundowning-like phenomena in a transgenic mouse model greatly adds to the validity of the APP23 model.

Heterozygous APP23 mice, expressing human amyloid-precursor protein with the Swedish double mutation and control littermates, were subjected to behavioral and neuromotor tasks at the age of 6-8 weeks, 3 and 6 months. A hidden-platform Morris-type water maze showed an age-dependent decline of spatial memory capacities in the APP23 model. From the age of 3 months onwards, the APP23 mice displayed major learning and memory deficits as demonstrated by severely impaired learning curves during acquisition and impaired probe trial performance. In addition to the cognitive deficit, APP23 mice displayed disturbed activity patterns. Overnight cage-activity recording showed hyperactivity in the transgenics for the three age groups tested. However, a short 2-h recording during dusk phase demonstrated lower activity levels in 6-month-old APP23 mice as compared to controls. Moreover, at this age, APP23 mice differed from control littermates in exploration and activity levels in the open-field paradigm. These findings are reminiscent of disturbances in circadian rhythms and activity observed in Alzheimer patients. Determination of plaque-associated human amyloid-beta 1-42 peptides in brain revealed a fivefold increase in heterozygous APP23 mice at 6 months as compared to younger transgenics. This increase coincided with the first appearance of plaques in hippocampus and neocortex. Spatial memory deficits preceded plaque formation and increase in plaque-associated amyloid-beta 1-42 peptides, but probe trial performance did correlate negatively with soluble amyloid-beta brain concentration in 3-month-old APP23 mutants. Detectable plaque formation is not the (only) causal factor contributing to memory defects in the APP23 model.