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1.
Cell ; 182(6): 1623-1640.e34, 2020 09 17.
Article in English | MEDLINE | ID: mdl-32946783

ABSTRACT

Human organoids recapitulating the cell-type diversity and function of their target organ are valuable for basic and translational research. We developed light-sensitive human retinal organoids with multiple nuclear and synaptic layers and functional synapses. We sequenced the RNA of 285,441 single cells from these organoids at seven developmental time points and from the periphery, fovea, pigment epithelium and choroid of light-responsive adult human retinas, and performed histochemistry. Cell types in organoids matured in vitro to a stable "developed" state at a rate similar to human retina development in vivo. Transcriptomes of organoid cell types converged toward the transcriptomes of adult peripheral retinal cell types. Expression of disease-associated genes was cell-type-specific in adult retina, and cell-type specificity was retained in organoids. We implicate unexpected cell types in diseases such as macular degeneration. This resource identifies cellular targets for studying disease mechanisms in organoids and for targeted repair in human retinas.


Subject(s)
Cell Differentiation/genetics , Organoids/cytology , Organoids/metabolism , Retina/cytology , Retina/metabolism , Single-Cell Analysis/methods , Synapses/physiology , Transcriptome/genetics , Cell Culture Techniques/methods , Cell Line , Electrophysiology , Female , Gene Expression Regulation, Developmental/genetics , Genetic Predisposition to Disease/genetics , Humans , In Situ Hybridization , Induced Pluripotent Stem Cells/cytology , Induced Pluripotent Stem Cells/metabolism , Microscopy, Electron , Multigene Family , Naphthoquinones , Organoids/radiation effects , Organoids/ultrastructure , Retina/pathology , Retina/radiation effects
2.
Blood ; 139(8): 1184-1197, 2022 02 24.
Article in English | MEDLINE | ID: mdl-33908607

ABSTRACT

Cancer cells are in most instances characterized by rapid proliferation and uncontrolled cell division. Hence, they must adapt to proliferation-induced metabolic stress through intrinsic or acquired antimetabolic stress responses to maintain homeostasis and survival. One mechanism to achieve this is reprogramming gene expression in a metabolism-dependent manner. MondoA (also known as Myc-associated factor X-like protein X-interacting protein [MLXIP]), a member of the MYC interactome, has been described as an example of such a metabolic sensor. However, the role of MondoA in malignancy is not fully understood and the underlying mechanism in metabolic responses remains elusive. By assessing patient data sets, we found that MondoA overexpression is associated with worse survival in pediatric common acute lymphoblastic leukemia (ALL; B-precursor ALL [B-ALL]). Using clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) and RNA-interference approaches, we observed that MondoA depletion reduces the transformational capacity of B-ALL cells in vitro and dramatically inhibits malignant potential in an in vivo mouse model. Interestingly, reduced expression of MondoA in patient data sets correlated with enrichment in metabolic pathways. The loss of MondoA correlated with increased tricarboxylic acid cycle activity. Mechanistically, MondoA senses metabolic stress in B-ALL cells by restricting oxidative phosphorylation through reduced pyruvate dehydrogenase activity. Glutamine starvation conditions greatly enhance this effect and highlight the inability to mitigate metabolic stress upon loss of MondoA in B-ALL. Our findings give novel insight into the function of MondoA in pediatric B-ALL and support the notion that MondoA inhibition in this entity offers a therapeutic opportunity and should be further explored.


Subject(s)
Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/metabolism , Neoplasm Proteins/metabolism , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/metabolism , Stress, Physiological , Animals , Basic Helix-Loop-Helix Leucine Zipper Transcription Factors/genetics , Cell Line, Tumor , Humans , Mice , Mice, Inbred BALB C , Mice, Knockout , Neoplasm Proteins/genetics , Precursor B-Cell Lymphoblastic Leukemia-Lymphoma/genetics
3.
Eur Radiol ; 2024 Feb 10.
Article in English | MEDLINE | ID: mdl-38337070

ABSTRACT

OBJECTIVES: To develop and share a deep learning method that can accurately identify optimal inversion time (TI) from multi-vendor, multi-institutional and multi-field strength inversion scout (TI scout) sequences for late gadolinium enhancement cardiac MRI. MATERIALS AND METHODS: Retrospective multicentre study conducted on 1136 1.5-T and 3-T cardiac MRI examinations from four centres and three scanner vendors. Deep learning models, comprising a convolutional neural network (CNN) that provides input to a long short-term memory (LSTM) network, were trained on TI scout pixel data from centres 1 to 3 to identify optimal TI, using ground truth annotations by two readers. Accuracy within 50 ms, mean absolute error (MAE), Lin's concordance coefficient (LCCC) and reduced major axis regression (RMAR) were used to select the best model from validation results, and applied to holdout test data. Robustness of the best-performing model was also tested on imaging data from centre 4. RESULTS: The best model (SE-ResNet18-LSTM) produced accuracy of 96.1%, MAE 22.9 ms and LCCC 0.47 compared to ground truth on the holdout test set and accuracy of 97.3%, MAE 15.2 ms and LCCC 0.64 when tested on unseen external (centre 4) data. Differences in vendor performance were observed, with greatest accuracy for the most commonly represented vendor in the training data. CONCLUSION: A deep learning model was developed that can identify optimal inversion time from TI scout images on multi-vendor data with high accuracy, including on previously unseen external data. We make this model available to the scientific community for further assessment or development. CLINICAL RELEVANCE STATEMENT: A robust automated inversion time selection tool for late gadolinium-enhanced imaging allows for reproducible and efficient cross-vendor inversion time selection. KEY POINTS: • A model comprising convolutional and recurrent neural networks was developed to extract optimal TI from TI scout images. • Model accuracy within 50 ms of ground truth on multi-vendor holdout and external data of 96.1% and 97.3% respectively was achieved. • This model could improve workflow efficiency and standardise optimal TI selection for consistent LGE imaging.

4.
Nucleic Acids Res ; 50(4): e20, 2022 02 28.
Article in English | MEDLINE | ID: mdl-34850137

ABSTRACT

The CRISPR-Cas9 genome editing tool is used to study genomic variants and gene knockouts, and can be combined with transcriptomic analyses to measure the effects of such alterations on gene expression. But how can one be sure that differential gene expression is due to a successful intended edit and not to an off-target event, without performing an often resource-demanding genome-wide sequencing of the edited cell or strain? To address this question we developed CRISPRroots: CRISPR-Cas9-mediated edits with accompanying RNA-seq data assessed for on-target and off-target sites. Our method combines Cas9 and guide RNA binding properties, gene expression changes, and sequence variants between edited and non-edited cells to discover potential off-targets. Applied on seven public datasets, CRISPRroots identified critical off-target candidates that were overlooked in all of the corresponding previous studies. CRISPRroots is available via https://rth.dk/resources/crispr.


Subject(s)
CRISPR-Cas Systems , Gene Editing , CRISPR-Cas Systems/genetics , Gene Editing/methods , Gene Knockout Techniques , RNA, Guide, Kinetoplastida/genetics , RNA-Seq
5.
Nucleic Acids Res ; 50(5): 2452-2463, 2022 03 21.
Article in English | MEDLINE | ID: mdl-35188540

ABSTRACT

Accelerated evolution of any portion of the genome is of significant interest, potentially signaling positive selection of phenotypic traits and adaptation. Accelerated evolution remains understudied for structured RNAs, despite the fact that an RNA's structure is often key to its function. RNA structures are typically characterized by compensatory (structure-preserving) basepair changes that are unexpected given the underlying sequence variation, i.e., they have evolved through negative selection on structure. We address the question of how fast the primary sequence of an RNA can change through evolution while conserving its structure. Specifically, we consider predicted and known structures in vertebrate genomes. After careful control of false discovery rates, we obtain 13 de novo structures (and three known Rfam structures) that we predict to have rapidly evolving sequences-defined as structures where the primary sequences of human and mouse have diverged at least twice as fast (1.5 times for Rfam) as nearby neutrally evolving sequences. Two of the three known structures function in translation inhibition related to infection and immune response. We conclude that rapid sequence divergence does not preclude RNA structure conservation in vertebrates, although these events are relatively rare.


Subject(s)
Genome , RNA , Animals , Evolution, Molecular , Mice , Phylogeny , RNA/chemistry , RNA/genetics , Vertebrates/genetics
6.
J Am Soc Nephrol ; 34(6): 1090-1104, 2023 06 01.
Article in English | MEDLINE | ID: mdl-36890644

ABSTRACT

SIGNIFICANCE STATEMENT: Hemodialysis (HD) results in reduced brain blood flow, and HD-related circulatory stress and regional ischemia are associated with brain injury over time. However, studies to date have not provided definitive direct evidence of acute brain injury during a HD treatment session. Using intradialytic magnetic resonance imaging (MRI) and spectroscopy to examine HD-associated changes in brain structure and neurochemistry, the authors found that multiple white (WM) tracts had diffusion imaging changes characteristic of cytotoxic edema, a consequence of ischemic insult and a precursor to fixed structural WM injury. Spectroscopy showed decreases in prefrontal N -acetyl aspartate (NAA) and choline concentrations consistent with energy deficit and perfusion anomaly. This suggests that one HD session can cause brain injury and that studies of interventions that mitigate this treatment's effects on the brain are warranted. BACKGROUND: Hemodialysis (HD) treatment-related hemodynamic stress results in recurrent ischemic injury to organs such as the heart and brain. Short-term reduction in brain blood flow and long-term white matter changes have been reported, but the basis of HD-induced brain injury is neither well-recognized nor understood, although progressive cognitive impairment is common. METHODS: We used neurocognitive assessments, intradialytic anatomical magnetic resonance imaging, diffusion tensor imaging, and proton magnetic resonance spectroscopy to examine the nature of acute HD-associated brain injury and associated changes in brain structure and neurochemistry relevant to ischemia. Data acquired before HD and during the last 60 minutes of HD (during maximal circulatory stress) were analyzed to assess the acute effects of HD on the brain. RESULTS: We studied 17 patients (mean age 63±13 years; 58.8% were male, 76.5% were White, 17.6% were Black, and 5.9% were of Indigenous ethnicity). We found intradialytic changes, including the development of multiple regions of white matter exhibiting increased fractional anisotropy with associated decreases in mean diffusivity and radial diffusivity-characteristic features of cytotoxic edema (with increase in global brain volumes). We also observed decreases in proton magnetic resonance spectroscopy-measured N -acetyl aspartate and choline concentrations during HD, indicative of regional ischemia. CONCLUSIONS: This study demonstrates for the first time that significant intradialytic changes in brain tissue volume, diffusion metrics, and brain metabolite concentrations consistent with ischemic injury occur in a single dialysis session. These findings raise the possibility that HD might have long-term neurological consequences. Further study is needed to establish an association between intradialytic magnetic resonance imaging findings of brain injury and cognitive impairment and to understand the chronic effects of HD-induced brain injury. CLINICAL TRIALS INFORMATION: NCT03342183 .


Subject(s)
Brain Injuries , White Matter , Humans , Male , Middle Aged , Aged , Female , Diffusion Tensor Imaging/methods , Aspartic Acid/metabolism , Magnetic Resonance Imaging , Brain Injuries/etiology , Brain Injuries/metabolism , Brain Injuries/pathology , Brain/diagnostic imaging , Brain/metabolism , White Matter/diagnostic imaging , Renal Dialysis/adverse effects , Spectrum Analysis , Choline/metabolism
7.
Neuroimage ; 273: 120092, 2023 06.
Article in English | MEDLINE | ID: mdl-37028736

ABSTRACT

Simultaneous EEG-fMRI is a powerful multimodal technique for imaging the brain, but its use in neurofeedback experiments has been limited by EEG noise caused by the MRI environment. Neurofeedback studies typically require analysis of EEG in real time, but EEG acquired inside the scanner is heavily contaminated with ballistocardiogram (BCG) artifact, a high-amplitude artifact locked to the cardiac cycle. Although techniques for removing BCG artifacts do exist, they are either not suited to real-time, low-latency applications, such as neurofeedback, or have limited efficacy. We propose and validate a new open-source artifact removal software called EEG-LLAMAS (Low Latency Artifact Mitigation Acquisition Software), which adapts and advances existing artifact removal techniques for low-latency experiments. We first used simulations to validate LLAMAS in data with known ground truth. We found that LLAMAS performed better than the best publicly-available real-time BCG removal technique, optimal basis sets (OBS), in terms of its ability to recover EEG waveforms, power spectra, and slow wave phase. To determine whether LLAMAS would be effective in practice, we then used it to conduct real-time EEG-fMRI recordings in healthy adults, using a steady state visual evoked potential (SSVEP) task. We found that LLAMAS was able to recover the SSVEP in real time, and recovered the power spectra collected outside the scanner better than OBS. We also measured the latency of LLAMAS during live recordings, and found that it introduced a lag of less than 50 ms on average. The low latency of LLAMAS, coupled with its improved artifact reduction, can thus be effectively used for EEG-fMRI neurofeedback. A limitation of the method is its use of a reference layer, a piece of EEG equipment which is not commercially available, but can be assembled in-house. This platform enables closed-loop experiments which previously would have been prohibitively difficult, such as those that target short-duration EEG events, and is shared openly with the neuroscience community.


Subject(s)
Camelids, New World , Neurofeedback , Adult , Animals , Humans , Magnetic Resonance Imaging/methods , Electroencephalography/methods , Artifacts , Evoked Potentials, Visual
8.
Neurobiol Dis ; 178: 105980, 2023 03.
Article in English | MEDLINE | ID: mdl-36572121

ABSTRACT

Alzheimer's disease (AD) is a progressive and irreversible brain disorder, which can occur either sporadically, due to a complex combination of environmental, genetic, and epigenetic factors, or because of rare genetic variants in specific genes (familial AD, or fAD). A key hallmark of AD is the accumulation of amyloid beta (Aß) and Tau hyperphosphorylated tangles in the brain, but the underlying pathomechanisms and interdependencies remain poorly understood. Here, we identify and characterise gene expression changes related to two fAD mutations (A79V and L150P) in the Presenilin-1 (PSEN1) gene. We do this by comparing the transcriptomes of glutamatergic forebrain neurons derived from fAD-mutant human induced pluripotent stem cells (hiPSCs) and their individual isogenic controls generated via precision CRISPR/Cas9 genome editing. Our analysis of Poly(A) RNA-seq data detects 1111 differentially expressed coding and non-coding genes significantly altered in fAD. Functional characterisation and pathway analysis of these genes reveal profound expression changes in constituents of the extracellular matrix, important to maintain the morphology, structural integrity, and plasticity of neurons, and in genes involved in calcium homeostasis and mitochondrial oxidative stress. Furthermore, by analysing total RNA-seq data we reveal that 30 out of 31 differentially expressed circular RNA genes are significantly upregulated in the fAD lines, and that these may contribute to the observed protein-coding gene expression changes. The results presented in this study contribute to a better understanding of the cellular mechanisms impacted in AD neurons, ultimately leading to neuronal damage and death.


Subject(s)
Alzheimer Disease , Induced Pluripotent Stem Cells , Humans , Amyloid beta-Peptides/metabolism , Transcriptome , Presenilin-1/genetics , Presenilin-1/metabolism , Induced Pluripotent Stem Cells/metabolism , Alzheimer Disease/genetics , Alzheimer Disease/metabolism , Mutation/genetics , Neurons/metabolism , Amyloid beta-Protein Precursor/genetics
9.
Chembiochem ; 24(11): e202300170, 2023 06 01.
Article in English | MEDLINE | ID: mdl-37057969

ABSTRACT

Mass spectrometry-based high-throughput screening methods combine the advantages of photometric or fluorometric assays and analytical chromatography, as they are reasonably fast (throughput ≥1 sample/min) and broadly applicable, with no need for labelled substrates or products. However, the established MS-based screening approaches require specialised and expensive hardware, which limits their broad use throughout the research community. We show that a more common instrumental platform, a single-quadrupole HPLC-MS, can be used to rapidly analyse diverse biotransformations by flow-injection mass spectrometry (FIA-MS), that is, by automated infusion of samples to the ESI-MS detector without prior chromatographic separation. Common organic buffers can be employed as internal standard for quantification, and the method provides readily validated activity and selectivity information with an analytical run time of one minute per sample. We report four application examples that cover a broad range of analyte structures and concentrations (0.1-50 mM before dilution) and diverse biocatalyst preparations (crude cell lysates and whole microbial cells). Our results establish FIA-MS as a versatile and reliable alternative to more traditional methods for screening enzymatic reactions.


Subject(s)
High-Throughput Screening Assays , Mass Spectrometry/methods , Chromatography, High Pressure Liquid/methods , High-Throughput Screening Assays/methods
10.
Eur J Clin Invest ; 53(4): e13914, 2023 Apr.
Article in English | MEDLINE | ID: mdl-36444723

ABSTRACT

BACKGROUND: D-dimer testing is known to have a high sensitivity at simultaneously low specificity, resulting in nonspecific elevations in a variety of conditions. METHODS: This retrospective study sought to assess diagnostic and prognostic features of D-dimers in cancer patients referred to the emergency department for suspected pulmonary embolism (PE) and deep vein thrombosis (DVT). In total, 526 patients with a final adjudicated diagnosis of PE (n = 83) and DVT (n = 69) were enrolled, whereas 374 patients served as the comparative group, in which venous thromboembolism (VTE) has been excluded. RESULTS: For the identification of VTE, D-dimers yielded the highest positive predictive value of 96% (95% confidence interval (CI), 85-99) at concentrations of 9.9 mg/L and a negative predictive value of 100% at .6 mg/L (95% CI, 97-100). At the established rule-out cut-off level of .5 mg/L, D-dimers were found to be very sensitive (100%) at a moderate specificity of nearly 65%. Using an optimised cut-off value of 4.9 mg/L increased the specificity to 95% for the detection of life-threatening VTE at the cost of moderate sensitivities (64%). During a median follow-up of 30 months, D-dimers positively correlated with the reoccurrence of VTE (p = .0299) and mortality in both cancer patients with VTE (p < .0001) and without VTE (p = .0008). CONCLUSIONS: Although D-dimer testing in cancer patients is discouraged by current guidelines, very high concentrations above the 10-fold upper reference limit contain diagnostic and prognostic information and might be helpful in risk assessment, while low concentrations remain useful for ruling out VTE.


Subject(s)
Neoplasms , Venous Thromboembolism , Humans , Venous Thromboembolism/diagnosis , Prognosis , Retrospective Studies , Fibrin Fibrinogen Degradation Products , Predictive Value of Tests
11.
Eur J Clin Invest ; 53(10): e14060, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37409393

ABSTRACT

BACKGROUND: Cancer is a well-known risk factor for venous thromboembolism (VTE). A combined strategy of D-dimer testing and clinical pre-test probability is usually used to exclude VTE. However, its effectiveness is diminished in cancer patients due to reduced specificity, ultimately leading to a decreased clinical utility. This review article seeks to provide a comprehensive summary of how to interpret D-dimer testing in cancer patients. METHODS: In accordance with PRISMA standards, literature pertaining to the diagnostic and prognostic significance of D-dimer testing in cancer patients was carefully chosen from reputable sources such as PubMed and the Cochrane databases. RESULTS: D-dimers have not only a diagnostic value in ruling out VTE but can also serve as an aid for rule-in if their values exceed 10-times the upper limit of normal. This threshold allows a diagnosis of VTE in cancer patients with a positive predictive value of more than 80%. Moreover, elevated D-dimers carry important prognostic information and are associated with VTE reoccurrence. A gradual increase in risk for all-cause death suggests that VTE is also an indicator of biologically more aggressive cancer types and advanced cancer stages. Considering the lack of standardization for D-dimer assays, it is essential for clinicians to carefully consider the variations in assay performance and the specific test characteristics of their institution. CONCLUSIONS: Standardizing D-dimer assays and developing modified pretest probability models specifically for cancer patients, along with adjusted cut-off values for D-dimer testing, could significantly enhance the accuracy and effectiveness of VTE diagnosis in this population.


Subject(s)
Fibrin Fibrinogen Degradation Products , Neoplasms , Humans , Neoplasms/blood , Neoplasms/complications , Neoplasms/diagnosis , Predictive Value of Tests , Risk Factors , Venous Thromboembolism/blood , Venous Thromboembolism/diagnosis , Venous Thromboembolism/prevention & control , Biological Assay/standards , Sensitivity and Specificity
12.
BMC Cancer ; 23(1): 1266, 2023 Dec 21.
Article in English | MEDLINE | ID: mdl-38129790

ABSTRACT

BACKGROUND: Shared decision-making has become of increased importance in choosing the most suitable treatment strategy for early rectal cancer, however, clinical decision-making is still primarily based on physicians' perspectives. Balancing quality of life and oncological outcomes is difficult, and guidance on patients' involvement in this subject in early rectal cancer is limited. Therefore, this study aimed to explore preferences and priorities of patients as well as physicians' perspectives in treatment for early rectal cancer. METHODS: In this qualitative study, semi-structured interviews were performed with early rectal cancer patients (n = 10) and healthcare providers (n = 10). Participants were asked which factors influenced their preferences and how important these factors were. Thematic analyses were performed. In addition, participants were asked to rank the discussed factors according to importance to gain additional insights. RESULTS: Patients addressed the following relevant factors: the risk of an ostomy, risk of poor bowel function and treatment related complications. Healthcare providers emphasized oncological outcomes as tumour recurrence, risk of an ostomy and poor bowel function. Patients perceived absolute risks of adverse outcome to be lower than healthcare providers and were quite willing undergo organ preservation to achieve a better prospect of quality of life. CONCLUSION: Patients' preferences in treatment of early rectal cancer vary between patients and frequently differ from assumptions of preferences by healthcare providers. To optimize future shared decision-making, healthcare providers should be aware of these differences and should invite patients to explore and address their priorities more explicitly during consultation. Factors deemed important by both physicians and patients should be expressed during consultation to decide on a tailored treatment strategy.


Subject(s)
Quality of Life , Rectal Neoplasms , Humans , Decision Making , Neoplasm Recurrence, Local , Health Personnel , Rectal Neoplasms/therapy
13.
J Magn Reson Imaging ; 2023 Aug 17.
Article in English | MEDLINE | ID: mdl-37589418

ABSTRACT

BACKGROUND: Ischemic heart disease (IHD) is linked to brain white matter (WM) breakdown but how age or disease effects WM integrity, and whether it is reversible using cardiac rehabilitation (CR), remains unclear. PURPOSE: To assess the effects of brain aging, cardiovascular disease, and CR on WM microstructure in brains of IHD patients following a cardiac event. STUDY TYPE: Retrospective. POPULATION: Thirty-five IHD patients (9 females; mean age = 59 ± 8 years), 21 age-matched healthy controls (10 females; mean age = 59 ± 8 years), and 25 younger controls (14 females; mean age = 26 ± 4 years). FIELD STRENGTH/SEQUENCE: 3 T diffusion-weighted imaging with single-shot echo planar imaging acquired at 3 months and 9 months post-cardiac event. ASSESSMENT: Tract-based spatial statistics (TBSS) and tractometry were used to compare fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) in cerebral WM between: 1) older and younger controls to distinguish age-related from disease-related WM changes; 2) IHD patients at baseline (pre-CR) and age-matched controls to investigate if cardiovascular disease exacerbates age-related WM changes; and 3) IHD patients pre-CR and post-CR to investigate the neuroplastic effect of CR on WM microstructure. STATISTICAL TESTS: Two-sample unpaired t-test (age: older vs. younger controls; IHD: IHD pre-CR vs. age-matched controls). One-sample paired t-test (CR: IHD pre- vs. post-CR). Statistical threshold: P < 0.05 (FWE-corrected). RESULTS: TBSS and tractometry revealed widespread WM changes in older controls compared to younger controls while WM clusters of decreased FA in the fornix and increased MD in body of corpus callosum were observed in IHD patients pre-CR compared to age-matched controls. Robust WM improvements (increased FA, increased AD) were observed in IHD patients post-CR. DATA CONCLUSION: In IHD, both brain aging and cardiovascular disease may contribute to WM disruptions. IHD-related WM disruptions may be favorably modified by CR. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: Stage 2.

14.
Brain Behav Immun ; 113: 353-373, 2023 10.
Article in English | MEDLINE | ID: mdl-37543250

ABSTRACT

Frontotemporal dementia (FTD) is a common cause of early-onset dementia, with no current treatment options. FTD linked to chromosome 3 (FTD3) is a rare sub-form of the disease, caused by a point mutation in the Charged Multivesicular Body Protein 2B (CHMP2B). This mutation causes neuronal phenotypes, such as mitochondrial deficiencies, accompanied by metabolic changes and interrupted endosomal-lysosomal fusion. However, the contribution of glial cells to FTD3 pathogenesis has, until recently, been largely unexplored. Glial cells play an important role in most neurodegenerative disorders as drivers and facilitators of neuroinflammation. Microglia are at the center of current investigations as potential pro-inflammatory drivers. While gliosis has been observed in FTD3 patient brains, it has not yet been systematically analyzed. In the light of this, we investigated the role of microglia in FTD3 by implementing human induced pluripotent stem cells (hiPSC) with either a heterozygous or homozygous CHMP2B mutation, introduced into a healthy control hiPSC line via CRISPR-Cas9 precision gene editing. These hiPSC were differentiated into microglia to evaluate the pro-inflammatory profile and metabolic state. Moreover, hiPSC-derived neurons were cultured with conditioned microglia media to investigate disease specific interactions between the two cell populations. Interestingly, we identified two divergent inflammatory microglial phenotypes resulting from the underlying mutations: a severe pro-inflammatory profile in CHMP2B homozygous FTD3 microglia, and an "unresponsive" CHMP2B heterozygous FTD3 microglial state. These findings correlate with our observations of increased phagocytic activity in CHMP2B homozygous, and impaired protein degradation in CHMP2B heterozygous FTD3 microglia. Metabolic mapping confirmed these differences, revealing a metabolic reprogramming of the CHMP2B FTD3 microglia, displayed as a compensatory up-regulation of glutamine metabolism in the CHMP2B homozygous FTD3 microglia. Intriguingly, conditioned CHMP2B homozygous FTD3 microglia media caused neurotoxic effects, which was not evident for the heterozygous microglia. Strikingly, IFN-γ treatment initiated an immune boost of the CHMP2B heterozygous FTD3 microglia, and conditioned microglia media exposure promoted neural outgrowth. Our findings indicate that the microglial profile, activity, and behavior is highly dependent on the status of the CHMP2B mutation. Our results suggest that the heterozygous state of the mutation in FTD3 patients could potentially be exploited in form of immune-boosting intervention strategies to counteract neurodegeneration.


Subject(s)
Frontotemporal Dementia , Induced Pluripotent Stem Cells , Humans , Frontotemporal Dementia/genetics , Frontotemporal Dementia/metabolism , Frontotemporal Dementia/pathology , Induced Pluripotent Stem Cells/metabolism , Microglia/metabolism , Endosomal Sorting Complexes Required for Transport/genetics , Endosomal Sorting Complexes Required for Transport/metabolism
15.
Biomacromolecules ; 24(1): 246-257, 2023 01 09.
Article in English | MEDLINE | ID: mdl-36464844

ABSTRACT

Poly(2-oxazoline)s (POx) have received substantial attention as poly(ethylene glycol) (PEG) alternatives in the biomedical field due to their biocompatibility, high functionality, and ease of synthesis. While POx have demonstrated strong potential as biomaterial constituents, the larger family of poly(cyclic imino ether)s (PCIE) to which POx belongs remains widely underexplored. One highly interesting sub-class of PCIE is poly(2,4-disubstituted-2-oxazoline)s (PdOx), which bear an additional substituent on the backbone of the polymers' repeating units. This allows fine-tuning of the hydrophilic/hydrophobic balance and renders the PdOx chiral when enantiopure 2-oxazoline monomers are used. Herein, we synthesize new water-soluble (R-/S-/RS-) poly(oligo(2-ethyl-4-methyl-2-oxazoline) methacrylate) (P(OEtMeOxMA)) bottlebrushes and compare them to well-established PEtOx- and PEG-based bottlebrush controls in terms of their physical properties, hydrophilicity, and biological behavior. We reveal that the P(OEtMeOxMA) bottlebrushes show a lower critical solution temperature behavior at a physiologically relevant temperature (∼44 °C) and that the enantiopure (R-/S-) variants display a chiral secondary structure. Importantly, we demonstrate the biocompatibility of the chiral P(OEtMeOxMA) bottlebrushes through cellular association and mouse biodistribution studies and show that these systems display higher immune cell association and organ accumulation than the two control polymers. These novel materials possess properties that hold promise for applications in the field of nanomedicine and may be beneficial carriers for therapeutics that require enhanced cellular association and immune cell interaction.


Subject(s)
Oxazoles , Water , Mice , Animals , Tissue Distribution , Oxazoles/chemistry , Polyethylene Glycols , Polymers/chemistry
16.
Am J Geriatr Psychiatry ; 31(2): 87-93, 2023 02.
Article in English | MEDLINE | ID: mdl-36253289

ABSTRACT

OBJECTIVE: To determine the current prevalence of perceived purpose in life (PIL) and its association with screening positive for mental disorders and suicidality in a nationally representative sample of predominantly older U.S. veterans. METHODS: Data were analyzed from the 2019-2020 National Health and Resilience in Veterans Study (N = 4,069; Mage = 62.2). Veterans were classified into three groups based on perceived PIL level (i.e., low, average, and high). Self-report assessments were administered to screen for mental disorders and suicidality. RESULTS: Most veterans endorsed average PIL (71.7%), while 16.0% endorsed low PIL and 12.4% endorsed high PIL. A "dose-response" association was observed between PIL and outcomes. High PIL was associated with 42%-94% reduced odds of screening positive for major depressive, generalized anxiety, posttraumatic stress, and substance use disorders, as well as suicide attempts, ideation, and future intent. CONCLUSION: Higher PIL is associated with lower odds of mental disorders and suicidality in U.S. veterans, underscoring the potential importance of interventions to bolster PIL in this population.


Subject(s)
Depressive Disorder, Major , Stress Disorders, Post-Traumatic , Suicide , Veterans , Humans , Aged , Veterans/psychology , Mental Health , Depressive Disorder, Major/psychology , Suicidal Ideation , Stress Disorders, Post-Traumatic/epidemiology
17.
Prev Med ; 170: 107495, 2023 05.
Article in English | MEDLINE | ID: mdl-37001606

ABSTRACT

General population studies suggest purpose in life (PIL) is associated with a number of positive outcomes, including better mental and physical health. At present, however, scarce research has examined how PIL relates to these outcomes in veterans. The goal of this study was to determine the current prevalence of different levels of PIL and their associations with reported physical health in a nationally representative sample of predominantly older U.S. veterans. Cross-sectional data were analyzed from the 2019-2020 National Health and Resilience in Veterans Study (N = 4069; M(age) = 62.2). Veterans were classified into low, average, and high PIL. Self-report assessments were administered to assess physical health conditions and physical functioning. Results showed most veterans endorsed average PIL (71.7%), while 16.0% endorsed low PIL and 12.3% endorsed high PIL. Low PIL was associated with lower overall self-reported health and physical and cognitive functioning, as well as higher bodily pain, somatic symptoms, and physical role limitations (Cohen's d = 0.06-0.77). Low PIL was also associated with elevated rates of several physical health conditions, including sleep disorders, as well as obesity and disability with activities of daily living (i.e., ADLs) or instrumental activities of daily living (i.e., IADLs). These results suggest low PIL is associated with physical health difficulties, and underscore the importance of assessing and monitoring PIL, and evaluating whether interventions to promote PIL may help improve physical health and vice versa.


Subject(s)
Disabled Persons , Stress Disorders, Post-Traumatic , Veterans , Humans , Aged , Activities of Daily Living/psychology , Cross-Sectional Studies , Self Report , Stress Disorders, Post-Traumatic/psychology
18.
Surg Endosc ; 37(6): 4279-4297, 2023 06.
Article in English | MEDLINE | ID: mdl-37099157

ABSTRACT

BACKGROUND: Quality of surgery has substantial impact on both short- and long-term clinical outcomes. This stresses the need for objective surgical quality assessment (SQA) for education, clinical practice and research purposes. The aim of this systematic review was to provide a comprehensive overview of all video-based objective SQA tools in laparoscopic procedures and their validity to objectively assess surgical performance. METHODS: PubMed, Embase.com and Web of Science were systematically searched by two reviewers to identify all studies focusing on video-based SQA tools of technical skills in laparoscopic surgery performed in a clinical setting. Evidence on validity was evaluated using a modified validation scoring system. RESULTS: Fifty-five studies with a total of 41 video-based SQA tools were identified. These tools were used in 9 different fields of laparoscopic surgery and were divided into 4 categories: the global assessment scale (GAS), the error-based assessment scale (EBAS), the procedure-specific assessment tool (PSAT) and artificial intelligence (AI). The number of studies focusing on these four categories were 21, 6, 31 and 3, respectively. Twelve studies validated the SQA tool with clinical outcomes. In 11 of those studies, a positive association between surgical quality and clinical outcomes was found. CONCLUSION: This systematic review included a total of 41 unique video-based SQA tools to assess surgical technical skills in various domains of laparoscopic surgery. This study suggests that validated SQA tools enable objective assessment of surgical performance with relevance for clinical outcomes, which can be used for training, research and quality improvement programs.


Subject(s)
Artificial Intelligence , Laparoscopy , Humans , Laparoscopy/education , Clinical Competence
19.
Int Psychogeriatr ; 35(10): 560-565, 2023 10.
Article in English | MEDLINE | ID: mdl-36715004

ABSTRACT

OBJECTIVE: Perceived purpose in life (PIL) has been linked to a broad range of adverse physical, mental, and cognitive outcomes. However, limited research has examined factors associated with PIL that can be targeted in prevention and treatment efforts in aging populations at heightened risk of adverse outcomes. Using data from predominantly older US veterans, we sought to identify important correlates of PIL. METHODS: Cross-sectional data were analyzed from the 2019-2020 National Health and Resilience in Veterans Study, which surveyed a nationally representative sample of 4069 US military veterans (Mage = 62.2). Elastic net and relative importance analyses were conducted to evaluate sociodemographic, military, health, and psychosocial variables that were strongly associated with PIL. RESULTS: Of the 39 variables entered into an elastic net analysis, 10 were identified as significant correlates of PIL. In order of magnitude, these were resilience (18.7% relative variance explained [RVE]), optimism (12.1%), depressive symptoms (11.3%), community integration (10.7%), gratitude (10.2%), loneliness (9.8%), received social support (8.6%), conscientiousness (8.5%), openness to experience (5.4%), and intrinsic religiosity (4.7%). CONCLUSIONS: Several modifiable psychosocial factors emerged as significant correlates of PIL in US military veterans. Interventions designed to target these factors may help increase PIL and mitigate risk for adverse health outcomes in this population.


Subject(s)
Resilience, Psychological , Stress Disorders, Post-Traumatic , Veterans , Humans , Aged , Veterans/psychology , Cross-Sectional Studies , Aging , Surveys and Questionnaires , Stress Disorders, Post-Traumatic/psychology
20.
Int J Mol Sci ; 24(6)2023 Mar 20.
Article in English | MEDLINE | ID: mdl-36982970

ABSTRACT

The survival of malignant leukemic cells is dependent on DNA damage repair (DDR) signaling. Reverse Phase Protein Array (RPPA) data sets were assembled using diagnostic samples from 810 adult and 500 pediatric acute myelogenous leukemia (AML) patients and were probed with 412 and 296 strictly validated antibodies, respectively, including those detecting the expression of proteins directly involved in DDR. Unbiased hierarchical clustering identified strong recurrent DDR protein expression patterns in both adult and pediatric AML. Globally, DDR expression was associated with gene mutational statuses and was prognostic for outcomes including overall survival (OS), relapse rate, and remission duration (RD). In adult patients, seven DDR proteins were individually prognostic for either RD or OS. When DDR proteins were analyzed together with DDR-related proteins operating in diverse cellular signaling pathways, these expanded groupings were also highly prognostic for OS. Analysis of patients treated with either conventional chemotherapy or venetoclax combined with a hypomethylating agent revealed protein clusters that differentially predicted favorable from unfavorable prognoses within each therapy cohort. Collectively, this investigation provides insight into variable DDR pathway activation in AML and may help direct future individualized DDR-targeted therapies in AML patients.


Subject(s)
Leukemia, Myeloid, Acute , Humans , Adult , Child , Prognosis , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , DNA Repair/genetics , DNA Damage , Discoidin Domain Receptors/genetics
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