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1.
Proc Natl Acad Sci U S A ; 120(4): e2216830120, 2023 01 24.
Article in English | MEDLINE | ID: mdl-36649413

ABSTRACT

It has been documented since the Renaissance that an air bubble rising in water will deviate from its straight, steady path to perform a periodic zigzag or spiral motion once the bubble is above a critical size. Yet, unsteady bubble rise has resisted quantitative description, and the physical mechanism remains in dispute. Using a numerical mapping technique, we for the first time find quantitative agreement with high-precision measurements of the instability. Our linear stability analysis shows that the straight path of an air bubble in water becomes unstable to a periodic perturbation (a Hopf bifurcation) above a critical spherical radius of R = 0.926 mm, within 2% of the experimental value. While it was previously believed that the bubble's wake becomes unstable, we now demonstrate a new mechanism, based on the interplay between flow and bubble deformation.


Subject(s)
Water , Motion
2.
Neuroimage ; 287: 120521, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38244877

ABSTRACT

Long-term memories are formed by repeated reactivation of newly encoded information during sleep. This process can be enhanced by using memory-associated reminder cues like sounds and odors. While auditory cueing has been researched extensively, few electrophysiological studies have exploited the various benefits of olfactory cueing. We used high-density electroencephalography in an odor-cueing paradigm that was designed to isolate the neural responses specific to the cueing of declarative memories. We show widespread cueing-induced increases in the duration and rate of sleep spindles. Higher spindle rates were most prominent over centro-parietal areas and largely overlapping with a concurrent increase in the amplitude of slow oscillations (SOs). Interestingly, greater SO amplitudes were linked to a higher likelihood of coupling a spindle and coupled spindles expressed during cueing were more numerous in particular around SO up states. We thus identify temporally and spatially coordinated enhancements of sleep spindles and slow oscillations as a candidate mechanism behind cueing-induced memory processing. Our results further demonstrate the feasibility of studying neural activity patterns linked to such processing using olfactory cueing during sleep.


Subject(s)
Cues , Memory Consolidation , Humans , Odorants , Sleep/physiology , Electroencephalography , Memory/physiology , Memory Consolidation/physiology
3.
Am J Hum Genet ; 108(1): 68-83, 2021 01 07.
Article in English | MEDLINE | ID: mdl-33385324

ABSTRACT

The proportion of samples with one or more close relatives in a genetic dataset increases rapidly with sample size, necessitating relatedness modeling and enabling pedigree-based analyses. Despite this, relatives are generally unreported and current inference methods typically detect only the degree of relatedness of sample pairs and not pedigree relationships. We developed CREST, an accurate and fast method that identifies the pedigree relationships of close relatives. CREST utilizes identity by descent (IBD) segments shared between a pair of samples and their mutual relatives, leveraging the fact that sharing rates among these individuals differ across pedigree configurations. Furthermore, CREST exploits the profound differences in sex-specific genetic maps to classify pairs as maternally or paternally related-e.g., paternal half-siblings-using the locations of autosomal IBD segments shared between the pair. In simulated data, CREST correctly classifies 91.5%-100% of grandparent-grandchild (GP) pairs, 80.0%-97.5% of avuncular (AV) pairs, and 75.5%-98.5% of half-siblings (HS) pairs compared to PADRE's rates of 38.5%-76.0% of GP, 60.5%-92.0% of AV, 73.0%-95.0% of HS pairs. Turning to the real 20,032 sample Generation Scotland (GS) dataset, CREST identified seven pedigrees with incorrect relationship types or maternal/paternal parent sexes, five of which we confirmed as mistakes, and two with uncertain relationships. After correcting these, CREST correctly determines relationship types for 93.5% of GP, 97.7% of AV, and 92.2% of HS pairs that have sufficient mutual relative data; the parent sex in 100% of HS and 99.6% of GP pairs; and it completes this analysis in 2.8 h including IBD detection in eight threads.


Subject(s)
Genome, Human/genetics , Female , Genetic Linkage/genetics , Genotype , Humans , Male , Models, Genetic , Pedigree , Scotland
4.
Blood ; 137(18): 2463-2480, 2021 05 06.
Article in English | MEDLINE | ID: mdl-33227818

ABSTRACT

Lineage plasticity and stemness have been invoked as causes of therapy resistance in cancer, because these flexible states allow cancer cells to dedifferentiate and alter their dependencies. We investigated such resistance mechanisms in relapsed/refractory early T-cell progenitor acute lymphoblastic leukemia (ETP-ALL) carrying activating NOTCH1 mutations via full-length single-cell RNA sequencing (scRNA-seq) of malignant and microenvironmental cells. We identified 2 highly distinct stem-like states that critically differed with regard to cell cycle and oncogenic signaling. Fast-cycling stem-like leukemia cells demonstrated Notch activation and were effectively eliminated in patients by Notch inhibition, whereas slow-cycling stem-like cells were Notch independent and rather relied on PI3K signaling, likely explaining the poor efficacy of Notch inhibition in this disease. Remarkably, we found that both stem-like states could differentiate into a more mature leukemia state with prominent immunomodulatory functions, including high expression of the LGALS9 checkpoint molecule. These cells promoted an immunosuppressive leukemia ecosystem with clonal accumulation of dysfunctional CD8+ T cells that expressed HAVCR2, the cognate receptor for LGALS9. Our study identified complex interactions between signaling programs, cellular plasticity, and immune programs that characterize ETP-ALL, illustrating the multidimensionality of tumor heterogeneity. In this scenario, combination therapies targeting diverse oncogenic states and the immune ecosystem seem most promising to successfully eliminate tumor cells that escape treatment through coexisting transcriptional programs.


Subject(s)
Carcinogenesis , Galectins/metabolism , Gene Expression Regulation, Leukemic , Immune Evasion , Neoplastic Stem Cells/pathology , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/pathology , Single-Cell Analysis/methods , Adolescent , Adult , Aged , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Child , Child, Preschool , Drug Resistance, Neoplasm , Female , Follow-Up Studies , Galectins/genetics , Hepatitis A Virus Cellular Receptor 2/genetics , Hepatitis A Virus Cellular Receptor 2/metabolism , Humans , Infant , Male , Middle Aged , Mutation , Neoplastic Stem Cells/immunology , Neoplastic Stem Cells/metabolism , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/genetics , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/immunology , Precursor T-Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Prognosis , RNA-Seq/methods , Tumor Cells, Cultured , Xenograft Model Antitumor Assays , Young Adult
5.
Biochemistry ; 61(20): 2248-2260, 2022 10 18.
Article in English | MEDLINE | ID: mdl-36194497

ABSTRACT

Enzyme stability and function can be affected by various environmental factors, such as temperature, pH, and ionic strength. Enzymes that are located outside the relatively unchanging environment of the cytosol, such as those residing in the periplasmic space of bacteria or extracellularly secreted, are challenged by more fluctuations in the aqueous medium. Bacterial alkaline phosphatases (APs) are generally affected by ionic strength of the medium, but this varies substantially between species. An AP from the marine bacterium Vibrio splendidus (VAP) shows complex pH-dependent activation and stabilization in the 0-1.0 M range of halogen salts and has been hypothesized to specifically bind chloride anions. Here, using X-ray crystallography and anomalous scattering, we have located two chloride binding sites in the structure of VAP, one in the active site and another one at a peripheral site. Further characterization of the binding sites using site-directed mutagenesis and small-angle X-ray scattering showed that upon binding of chloride to the peripheral site, structural dynamics decreased locally, resulting in thermal stabilization of the VAP active conformation. Binding of the chloride ion in the active site did not displace the bound inorganic phosphate product, but it may promote product release by facilitating rotational stabilization of the substrate-binding Arg129. Overall, these results reveal the complex nature and dynamics of chloride binding to enzymes through long-range modulation of electronic potential in the vicinity of the active site, resulting in increased catalytic efficiency and stability.


Subject(s)
Alkaline Phosphatase , Vibrio , Alkaline Phosphatase/chemistry , Binding Sites , Chlorides , Crystallography, X-Ray , Halogens , Hydrogen-Ion Concentration , Phosphates , Salts
6.
Prostate ; 82(5): 584-597, 2022 04.
Article in English | MEDLINE | ID: mdl-35084050

ABSTRACT

BACKGROUND: Primary and metastatic prostate cancers have low mutation rates and recurrent alterations in a small set of genes, enabling targeted sequencing of prostate cancer-associated genes as an efficient approach to characterizing patient samples (compared to whole-exome and whole-genome sequencing). For example, targeted sequencing provides a flexible, rapid, and cost-effective method for genomic assessment of patient-derived cell lines to evaluate fidelity to initial patient tumor samples. METHODS: We developed a prostate cancer-specific targeted next-generation sequencing (NGS) panel to detect alterations in 62 prostate cancer-associated genes as well as recurring gene fusions with ETS family members, representing the majority of common alterations in prostate cancer. We tested this panel on primary prostate cancer tissues and blood biopsies from patients with metastatic prostate cancer. We generated patient-derived cell lines from primary prostate cancers using conditional reprogramming methods and applied targeted sequencing to evaluate the fidelity of these cell lines to the original patient tumors. RESULTS: The prostate cancer-specific panel identified biologically and clinically relevant alterations, including point mutations in driver oncogenes and ETS family fusion genes, in tumor tissues from 29 radical prostatectomy samples. The targeted panel also identified genomic alterations in cell-free DNA and circulating tumor cells (CTCs) from patients with metastatic prostate cancer, and in standard prostate cancer cell lines. We used the targeted panel to sequence our set of patient-derived cell lines; however, no prostate cancer-specific mutations were identified in the tumor-derived cell lines, suggesting preferential outgrowth of normal prostate epithelial cells. CONCLUSIONS: We evaluated a prostate cancer-specific targeted NGS panel to detect common and clinically relevant alterations (including ETS family gene fusions) in prostate cancer. The panel detected driver mutations in a diverse set of clinical samples of prostate cancer, including fresh-frozen tumors, cell-free DNA, CTCs, and cell lines. Targeted sequencing of patient-derived cell lines highlights the challenge of deriving cell lines from primary prostate cancers and the importance of genomic characterization to credential candidate cell lines. Our study supports that a prostate cancer-specific targeted sequencing panel provides an efficient, clinically feasible approach to identify genetic alterations across a spectrum of prostate cancer samples and cell lines.


Subject(s)
Cell-Free Nucleic Acids , Prostatic Neoplasms , Cell Line , Credentialing , High-Throughput Nucleotide Sequencing/methods , Humans , Male , Mutation , Prostatic Neoplasms/genetics
7.
BMC Plant Biol ; 22(1): 327, 2022 Jul 08.
Article in English | MEDLINE | ID: mdl-35799123

ABSTRACT

BACKGROUND: Sassafras has been considered to belong to trib. Laureae of Lauraceae and has been assumed to have unisexual flowers. However, recent molecular phylogenetic studies have consistently suggested that Sassafras does not belong to the trib. Laureae but to Cinnamomeae and that it is nested within Cinnamomum. A recent morphological study revealed that one of the Asian species, S. randaiense, possesses bisexual flowers that are plesiomorphic in the family Lauraceae. As reports on the flower structure of the second Asian species, S. tzumu, have been contradictory, we wanted to ascertain if it has bisexual flowers or not. If the flowers were bisexual, could earlier reports that they were unisexual have been based on dichogamous flowering? RESULTS: In this study, we investigated two populations of S. tzumu. We found that this species has determinate botryoid racemes, and possesses bisexual flowers. Among the three extant species, S. tzumu is more similar to its sister species S. randaiense but markedly different from the American S. albidum: the two Asian species possess bisexual flowers while the American species has unisexual flowers. The bisexual flower of S. tzumu is protogynous, and shows two phenological phases typical of Lauraceae: 1) in a flower, the pistil functions first, the stigma is fresh and white, stamens of the outer two whorls are spreading, anthers do not open, and the staminodes secrete nectar at this stage; 2) in the second phase, the stigma becomes brown, staminodes are withered, stamens of the third whorl stand up and surround the pistil, glands of the third whorl of stamens secrete nectar, and the anthers open and release pollen. CONCLUSIONS: The similarity of racemose inflorescences between Sassafras and some members of Laureae were caused by parallel evolution; the racemose inflorescence of ancestral Sassafras originated from the thyrsoid-cymose inflorescence in Cinnamomum. The Asian species S. tzumu and S. randaiense possess bisexual flowers with two phenological phases, the American S. albidum evolved unisexual flowers independently from other clades with unisexual flowers in the Lauraceae, i.e., the Laureae, Alseodaphnopsis in the Perseeae and the unisexual clade in the Ocotea complex of the Cinnamomeae.


Subject(s)
Lauraceae , Sassafras , Flowers/anatomy & histology , Phylogeny , Plant Nectar
8.
Clin Transplant ; 36(10): e14649, 2022 10.
Article in English | MEDLINE | ID: mdl-35297508

ABSTRACT

BACKGROUND: The optimal analgesic strategy for patients undergoing donor hepatectomy is not known and the potential short- and long-term physical and psychological consequences of complications are significant. OBJECTIVES: To identify whether a multimodal approach to pain of the donor intraoperatively enhances immediate and short-term outcomes after living liver donation, and to provide international expert panel recommendations. DATA SOURCES: Ovid MEDLINE, Embase, Scopus, Google Scholar, and Cochrane Central. METHODS: Systematic review following PRISMA guidelines and recommendations using the GRADE approach derived from an international expert panel. PROSPERO 2021 CRD42021260699. RESULTS: Nine studies assessing multi-modal analgesia strategies were included in a qualitative assessment. Interventions included local, regional, and neuro-axial anesthetic techniques, pharmacological intervention (NSAIDs, COX-2 inhibitors, ketamine, dexmedetomidine, and lidocaine), and acupuncture. Overall, there was a significant (40%) reduction in opioid requirement on day 1 and a significant reduction in pain scores in the intervention vs control groups. Significant reductions in either length of stay or post-operative complications were demonstrated in four of nine studies. CONCLUSIONS: Opioid use for patients undergoing donor hepatectomy is likely to impact both their short- and long-term outcomes. To reduce post-operative pain scores, shorten length of hospital stay, and promote earlier post-operative return of bowel function, we recommend that multi-modal analgesia be offered to patients undergoing living donor hepatectomy. Further research is required to confirm which multi-modal techniques are most associated with enhanced recovery in living liver donors.


Subject(s)
Analgesics, Opioid , Pain Management , Humans , Pain Management/adverse effects , Pain Management/methods , Analgesics, Opioid/therapeutic use , Pain, Postoperative/chemically induced , Lidocaine/adverse effects , Hepatectomy , Liver
9.
Phytopathology ; 112(2): 414-421, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34080915

ABSTRACT

Until recently, genotypes of Phytophthora infestans were regionally distributed in Europe, with populations in western Europe being dominated by clonal lineages and those in northern Europe being genetically diverse because of frequent sexual reproduction. However, since 2013 a new clonal lineage (EU_41_A2) has successfully established itself and expanded in the sexually recombining P. infestans populations of northern Europe. The objective of this study was to study phenotypic traits of the new clonal lineage of P. infestans, which may explain its successful establishment and expansion within sexually recombining populations. Fungicide sensitivity, aggressiveness, and virulence profiles of isolates of EU_41_A2 were analyzed and compared with those of the local sexual populations from Denmark, Norway, and Estonia. None of the phenotypic data obtained from the isolates collected from Denmark, Estonia, and Norway independently explained the invasive success of EU_41_A2 within sexual Nordic populations. Therefore, we hypothesize that the expansion of this new genotype could result from a combination of fitness traits and more favorable environmental conditions that have emerged in response to climate change.


Subject(s)
Phytophthora infestans , Solanum tuberosum , Genotype , Phenotype , Phytophthora infestans/genetics , Plant Diseases
10.
Acta Anaesthesiol Scand ; 66(6): 696-703, 2022 07.
Article in English | MEDLINE | ID: mdl-35325467

ABSTRACT

BACKGROUND: Emergence delirium (ED) and postoperative delirium (POD) are associated with increased morbidity and mortality and occur in up to one-third of patients undergoing major non-cardiac surgery, where the underlying pathogenesis is multifactorial, including increased inflammation. We aimed to assess the effect of pre-operative high- versus low-dose glucocorticoid on the occurrence of ED and POD. METHODS: This was a substudy from a randomized, double-blinded clinical trial. Patients ≥18 years, undergoing open liver resection were randomized 1:1 to high-dose (HD, 10 mg/kg methylprednisolone) or low-dose (LD, 8 mg dexamethasone) glucocorticoid and assessed for ED and POD for a maximum of 4 days during hospitalization. The 3-min Diagnostic Interview for CAM-defined delirium (3D-CAM) was used for assessment, 15 and 90 min after arrival in the post-anesthesia care unit (PACU), and subsequently once daily in the ward. RESULTS: Fifty-three patients were included in this secondary substudy (26 HD-group and 27 LD-group). ED occurred in n = 5 HD versus n = 6 LD patients 15 min after PACU arrival. At 90 min after PACU arrival, 4 patients had ED, all from LD-group, and resulted in significantly longer PACU admission, 273 versus 178 min in ED versus Non-ED patients. During the first 4 days in the ward, n = 5 patients had at least one occurrence of POD, all from LD-group. CONCLUSIONS: The primary finding of the current substudy was a lower occurrence of ED/POD in the PACU 90 min after arrival and during the first four postoperative days in patients receiving high-dose glucocorticoid compared with patients receiving low-dose glucocorticoid. The two study groups were not evenly balanced concerning known explanatory factors, i.e., age and size of surgery, which calls for larger studies to elucidate the matter.


Subject(s)
Delirium , Emergence Delirium , Anesthesia, General/methods , Delirium/epidemiology , Delirium/etiology , Delirium/prevention & control , Emergence Delirium/epidemiology , Emergence Delirium/prevention & control , Glucocorticoids , Humans , Liver , Postoperative Complications/epidemiology , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Prospective Studies
11.
Langenbecks Arch Surg ; 407(8): 3833-3841, 2022 Dec.
Article in English | MEDLINE | ID: mdl-35857097

ABSTRACT

PURPOSE: Atypical variants of the hepatic artery are common and pose a technical challenge for normothermic machine perfusion (NMP). The transplant surgeon has three options when confronted with hepatic arterial variation in a liver graft to be subjected to NMP: to perform arterial reconstruction (i) prior, (ii) during, or (iii) following NMP. METHODS: Herein, we report our experience and technical considerations with pre-NMP reconstruction. Out of 52 livers, 9 had an atypical hepatic artery (HA): 3 replaced right HA, 3 replaced left HA, 1 accessory left HA, 1 accessory left and right HA, and 1 replaced left and right HA. RESULTS: Reconstruction was conducted during back-table preparation. A single vascular conduit was created in all grafts to allow single arterial cannulation for NMP, necessitating only one arterial anastomosis within the recipient. All grafts were subjected to NMP and subsequently successfully transplanted. CONCLUSION: Our approach is being advocated for as it preserves the ability to alter the reconstruction in case of problems resulting from the reconstruction itself, thereby allowing functional evaluation of the reconstruction prior transplantation, permitting simultaneous reperfusion in the recipient, and providing the shortest possible duration for vascular reconstruction once the graft is rewarming non-perfused within the recipient. In addition, in light of the frequency of technically demanding reconstructions with very small vessels, we consider our technique beneficial as the procedure can be performed under ideal conditions at the back-table.


Subject(s)
Liver Transplantation , Organ Preservation , Humans , Organ Preservation/methods , Perfusion/methods , Liver Transplantation/methods , Hepatic Artery/surgery , Liver
12.
Rheumatol Int ; 42(2): 329-339, 2022 02.
Article in English | MEDLINE | ID: mdl-34272604

ABSTRACT

Fatigue is a common symptom in patients with rheumatoid arthritis (RA) and in patients with cancer (CA). The aim was to investigate the degree of fatigue in RA patients as compared to CA patients as well as potential influencing factors on RA-related fatigue. This was a retrospective analyses of two prospective cohort studies that used the EORTC QLQ-FA12 as a common instrument to assess fatigue. The cohort of RA patients was based on a nationwide survey in Germany. The cohort of CA patients was recruited in the context of an international validation field study. Multivariable ANCOVAs compared levels of fatigue between the two cohorts, also including various subgroup analyses. Regression analyses explored influencing factors on RA patients' fatigue. Data of n = 705 RA patients and of n = 943 CA patients were available for analyses. RA patients reported significantly higher Physical Fatigue (mean difference = 7.0, 95% CI 4.2-9.7, p < 0.001) and Social Sequelae (mean difference = 7.5, 95% CI 4.7-10.2, p < 0.001). CA patients reported higher Cognitive Fatigue (mean difference = 3.5, 95% CI 1.4-5.6, p = 0.001). No differences in Emotional Fatigue (p = 0.678) and Interference with Daily Life (p = 0.098) were found. In RA patients, mental health and pain were associated with fatigue (p values < 0.001). RA patients showed a considerable level of fatigue that is comparable to and in certain cases even higher than that of CA patients. The implementation of standardized diagnostic procedures and interventions to reduce fatigue in RA patients are recommended.


Subject(s)
Arthritis, Rheumatoid/epidemiology , Fatigue/epidemiology , Neoplasms/epidemiology , Adult , Aged , Aged, 80 and over , Fatigue/etiology , Female , Humans , Male , Middle Aged , Quality of Life , Self Report , Severity of Illness Index
13.
J Sports Sci ; 40(19): 2159-2165, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36441611

ABSTRACT

This study aims to investigate the presence of the relative age effect (RAE) in (semi-)professional cycling, especially within selecting cyclists for Continental (CT) development teams. Data were collected from www.procyclingstats.com (PCS). Cyclists out of the top-25 countries of the PCS ranking that were part of a CT team between 2005 and 2016 and born between January 1986 and December 1997 were included (n = 2854). Distributions of cyclists in different birth quarters (Q1, Q2, Q3 and Q4) as well as for different starting years at CT level (U23year1, U23year2, U23year3 and U23year4) and reaching professional level or not were investigated using the Chi-square goodness-of-fit test. A RAE was found for cyclists that did not reach professional level, which can be explained by cyclists starting at CT level U23year1 and U23year2 (19 and 20 years old). Meaning that for cyclists at 19 and 20 years old, there is a selection bias towards relatively older (Q1) cyclists at the expense of relatively younger (Q4) cyclists. Within the cyclists that reached professional level, no RAE was found, indicating that the RAE diminishes at professional level. This study provides insight into possible selection errors while selecting cyclists for CT development teams.


Subject(s)
Aptitude , Bicycling , Humans , Young Adult , Adult , Age Factors
14.
HPB (Oxford) ; 24(11): 2022-2028, 2022 11.
Article in English | MEDLINE | ID: mdl-35973930

ABSTRACT

BACKGROUND: The principles of enhanced recovery after surgery (ERAS) are being applied to still more advanced procedures. Liver transplantation offers a unique opportunity for a multimodal approach including donor care as well. Our objective was to determine if ERAS was applicable and safe in orthotopic liver transplantation (OLT). METHODS: A national single centre retrospective study showing the implementation of ERAS from 2013 to 2019 with the proceeding 2 years serving as baseline. The primary endpoints were mortality, length of stay (LOS) in the ward and intensive care unit stay. Secondary endpoints were complications estimated by Dindo-Clavien classification, comprehensive complication index (CCI®) and re-admissions. RESULTS: A total of 334 patients were included. LOS was significantly reduced from a median of 22.5 days at introduction to 14 days at 2019. Cold ischaemia time was reduced from a mean of 10.7 to 6.0 h and the use of blood products (erythrocytes, plasma and thrombocytes) from a median of 28 to 6 units. Complications were reduced in severity. Mortality and readmission rates were not affected. CONCLUSION: ERAS principles are safe and recommended in patients undergoing OLT resulting in reduced severity of complications and LOS without affecting re-admissions or mortality.


Subject(s)
Enhanced Recovery After Surgery , Liver Transplantation , Humans , Liver Transplantation/adverse effects , Retrospective Studies , Cohort Studies , Postoperative Complications/etiology , Length of Stay
15.
Neuroimage ; 224: 117452, 2021 01 01.
Article in English | MEDLINE | ID: mdl-33059050

ABSTRACT

Sleep spindles are crucial to memory consolidation. Cortical gamma oscillations (30-100 Hz) are considered to reflect processing of memory in local cortical networks. The temporal and regulatory relationship between spindles and gamma activity might therefore provide clues into how sleep strengthens cortical memory representations. Here, combining EEG with MEG recordings during sleep in healthy humans (n = 12), we investigated the temporal relationships of cortical gamma band activity, always measured by MEG, during fast (12-16 Hz) and slow (8-12 Hz) sleep spindles detected in the EEG or MEG. Time-frequency distributions did not show a consistent coupling of gamma to the spindle oscillation, although activity in the low gamma (30-40 Hz) and neighboring beta range (<30 Hz) was generally increased during spindles. However, more fine-grained analyses of cross-frequency interactions revealed that both low and high gamma power (30-100 Hz) was coupled to the phase of slow and fast EEG spindles, importantly, with this coupling at a fixed phase only for the oscillations within an individual spindle, but with variable phase across spindles. We did not observe any coupling of gamma activity for spindles detected solely in the MEG and not in parallel EEG recordings, raising the possibility that these are more local spindles of different quality. Similar to fast spindle activity, low gamma band power followed a ~0.025 Hz infraslow rhythm during sleep whose frequency, however, was significantly faster than that of spindle activity. Our findings suggest a general function of fast and slow spindles that by spanning larger cortical networks might serve to synchronize gamma band activity occurring in more local but distributed networks. Thereby, spindles might help linking local memory processing between distributed networks.


Subject(s)
Cerebral Cortex/physiology , Electroencephalography , Gamma Rhythm/physiology , Magnetoencephalography , Adult , Brain/diagnostic imaging , Brain/physiology , Cerebral Cortex/diagnostic imaging , Female , Healthy Volunteers , Humans , Male , Memory Consolidation/physiology , Polysomnography , Sleep/physiology , Sleep Stages/physiology , Young Adult
16.
J Sleep Res ; 30(5): e13335, 2021 10.
Article in English | MEDLINE | ID: mdl-33709537

ABSTRACT

Visual perceptual learning refers to long-lasting performance improvements on a visual skill - an ability supported by plastic changes in early visual brain areas. Visual perceptual learning has been shown to be induced by training and to benefit from consolidation during sleep, presumably via the reactivation of learning-associated neuronal firing patterns. However, previous studies have almost exclusively relied on a single paradigm, the texture discrimination task, on which performance improvements may rely on higher-order rather than lower-level perceptual skills. In the present study, we tested whether sleep has beneficial effects on a visual disparity discrimination task. We confirm previous findings in showing that the ability to discriminate different disparities is unaffected by sleep during a 12-hr retention period after training. Importantly, we extend these results by providing evidence against an effect of sleep on the generalisation of improved disparity discrimination across the vertical meridian. By relying on a between-subject design, we further exclude carry-over effects as a possible confound present in previous findings. These data argue against sleep as an important factor in the consolidation of a low-level perceptual skill. This sets important constraints on models of the role of sleep and sleep-associated neural reactivation in the consolidation of non-declarative memories.


Subject(s)
Memory , Vision Disparity , Generalization, Psychological , Humans , Learning , Sleep
17.
BMC Surg ; 21(1): 312, 2021 Jul 14.
Article in English | MEDLINE | ID: mdl-34261457

ABSTRACT

BACKGROUND: For colorectal liver metastases, surgery is a high-risk procedure due to perioperative morbidity. The objective was to assess severity of complications after fast-track liver surgery for colorectal liver metastases and their impact on morbidity and mortality. METHODS: All patients were treated according to the same fast-track programme. Complications were graded according to the Clavien-Dindo classification for patients undergoing surgery from 2013 to 2015. Correlation between complications and length of stay was analysed by multivariate linear regression. RESULTS: 564 patient cases were included of which three patients died within 3 months (0.53%, 95% CI: 0.17-1.64%). Complications were common with Grade ≤ 2 in 167 patients (30%) and ≥ Grade 3a in 93 (16%). Patients without complications had a mean length of stay of 4.1 days, which increased with complications: 1.4 days (95% CI: 1.3-1.5) for Grade 2, 1.7 days (1.5-2.0) for Grade 3a, 2.3 days (1.7-3.0) for Grade 3b, 2.6 days (1.6-4.2) for Grade 4a, and 2.9 days (2.8-3.1) for Grade 4b. Following were associated with increased length of stay: complication severity grade, liver insufficiency, ascites, biliary, cardiopulmonary, and infectious complications. CONCLUSIONS: Complications after liver surgery for colorectal liver metastases, in a fast track setting, were associated with low mortality, and even severe complications only prolonged length of stay to a minor degree.


Subject(s)
Colorectal Neoplasms , Liver Neoplasms , Cohort Studies , Colorectal Neoplasms/surgery , Humans , Length of Stay , Liver Neoplasms/surgery , Morbidity , Postoperative Complications/epidemiology
18.
Nephrol Dial Transplant ; 35(3): 519-526, 2020 03 01.
Article in English | MEDLINE | ID: mdl-30649437

ABSTRACT

BACKGROUND: Renal dysfunction is a serious late complication after liver transplantation (LTX), but there are no studies addressing the early changes associated with this complication. METHODS: We prospectively studied glomerular filtration rate (GFR) before and at 1, 3 and 12 weeks after LTX using 51Cr-labelled ethylenediaminetetraacetic acid clearance in 37 adult consecutive patients who underwent non-acute first LTX. RESULTS: The mean (±SD) age was 49.5 ± 9.5 years, and the male:female sex ratio was 21:16. Diagnoses were autoimmune liver diseases (17), alcoholic cirrhosis (10) and other diseases (10). Immunosuppressive treatment consisted predominantly of triple-drug therapy. A total of 27 of the 37 patients were eligible for GFR analysis at all times. The mean (±SD) GFR was 86 ± 26 mL/min/1.73 m2 before LTX, and 77 ± 30 mL/min/1.73 m2 at 1 week, 64 ± 27 mL/min/1.73 m2 at 3 weeks and 64 ± 23 mL/min/1.73 m2 at 12 weeks after LTX, comparable to a reduction in mean GFR compared with baseline values of 10% (P = 0.1907), 25% (P = 0.0010) and 26% (P = 0.0007). Age and number of blood transfusions during surgery were identified as risk factors for this decline as well as gender, but not pre-transplant diagnosis, model of end-stage liver disease score, cold ischaemia time or post-transplant area under the curve tacrolimus during Days 0-14. CONCLUSIONS: Using measured rather than estimated GFR, our results show that severe renal impairment occurs during the first week after LTX. These results emphasize the need for more studies addressing renoprotective treatment strategies.


Subject(s)
Acute Kidney Injury/diagnosis , Biomarkers/metabolism , Chromium Radioisotopes/metabolism , Edetic Acid/metabolism , Liver Transplantation/adverse effects , Acute Kidney Injury/etiology , Acute Kidney Injury/metabolism , Female , Glomerular Filtration Rate , Humans , Male , Middle Aged , Prospective Studies , Risk Factors
19.
Int J Mol Sci ; 21(18)2020 Sep 04.
Article in English | MEDLINE | ID: mdl-32899772

ABSTRACT

To ameliorate ischemia-induced graft injury, optimal organ preservation remains a critical hallmark event in solid organ transplantation. Although numerous preservation solutions are in use, they still have functional limitations. Here, we present a concise review of a modified Histidine-Tryptophan-Ketoglutarate (HTK) solution, named HTK-N. Its composition differs from standard HTK solution, carrying larger antioxidative capacity and providing inherent toxicity as well as improved tolerance to cold aiming to attenuate cold storage injury in organ transplantation. The amino acids glycine, alanine and arginine were supplemented, N-acetyl-histidine partially replaced histidine, and aspartate and lactobionate substituted chloride. Several in vitro studies confirmed the superiority of HTK-N in comparison to HTK, being tested in vivo in animal models for liver, kidney, pancreas, small bowel, heart and lung transplantation to adjust ingredients for required conditions, as well as to determine its innocuousness, applicability and potential advantages. HTK-N solution has proven to be advantageous especially in the preservation of liver and heart grafts in vivo and in vitro. Thus, ongoing clinical trials and further studies in large animal models and consequently in humans are inevitable to show its ability minimizing ischemia-induced graft injury in the sequel of organ transplantation.


Subject(s)
Organ Preservation Solutions/chemistry , Organ Preservation/methods , Alanine , Animals , Arginine , Cryopreservation/methods , Glucose/chemistry , Glucose/metabolism , Glycine , Humans , Liver/drug effects , Mannitol/chemistry , Mannitol/metabolism , Organ Transplantation , Pancreas/drug effects , Potassium Chloride/chemistry , Potassium Chloride/metabolism , Procaine/chemistry , Procaine/metabolism , Reperfusion Injury
20.
Int J Mol Sci ; 21(15)2020 Jul 22.
Article in English | MEDLINE | ID: mdl-32707886

ABSTRACT

Intestinal ischemia reperfusion injury (IRI) is an inherent, unavoidable event of intestinal transplantation, contributing to allograft failure and rejection. The inflammatory state elicited by intestinal IRI is characterized by heightened leukocyte recruitment to the gut, which is amplified by a cross-talk with platelets at the endothelial border. Sulforaphane (SFN), a naturally occurring isothiocyanate, exhibits anti-inflammatory characteristics and has been shown to reduce platelet activation and block leukocyte adhesion. Thus, the aim of this study was to investigate protective effects and mechanism of action of SFN in a murine model of intestinal IRI. Intestinal IRI was induced by superior mesenteric artery occlusion for 30 min, followed by reperfusion for 2 h, 8 h or 24 h. To investigate cellular interactions, leukocytes were in vivo stained with rhodamine and platelets were harvested from donor animals and ex vivo stained. Mice (C57BL/6J) were divided into three groups: (1) control, (2) SFN treatment 24 h prior to reperfusion and (3) SFN treatment 24 h prior to platelet donation. Leukocyte and platelet recruitment was analyzed via intravital microscopy. Tissue was analyzed for morphological alterations in intestinal mucosa, barrier permeability, and leukocyte infiltration. Leukocyte rolling and adhesion was significantly reduced 2 h and 8 h after reperfusion. Mice receiving SFN treated platelets exhibited significantly decreased leukocyte and platelet recruitment. SFN showed protection for intestinal tissue with less damage observed in histopathological and ultrastructural evaluation. In summary, the data presented provide evidence for SFN as a potential therapeutic strategy against intestinal IRI.


Subject(s)
Blood Platelets/drug effects , Intestinal Mucosa/drug effects , Isothiocyanates/pharmacology , Leukocytes/drug effects , Reperfusion Injury/prevention & control , Animals , Blood Platelets/pathology , Disease Models, Animal , Intestinal Mucosa/pathology , Intestinal Mucosa/ultrastructure , Isothiocyanates/therapeutic use , Leukocytes/immunology , Leukocytes/pathology , Male , Mice , Mice, Inbred C57BL , Microscopy, Electron , Microscopy, Fluorescence , Neutrophils/drug effects , Neutrophils/immunology , Neutrophils/pathology , Platelet Activation/drug effects , Reperfusion Injury/immunology , Reperfusion Injury/pathology , Sulfoxides
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