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1.
Article in English | MEDLINE | ID: mdl-38967455

ABSTRACT

BACKGROUND AND OBJECTIVES: In endoscopic endonasal approaches (EEAs) for skull base pathologies, endoscope view obscuration remains a persistent, time-consuming, and distracting issue for surgeons and may result in increased operative time. The endonasal access guide (EAG) has been demonstrated as a possible adjunct to minimize these events. However, to date, there have been no comparative studies performed and the potential time savings by using EAGs have yet to be quantified. This cohort study aimed to determine the operative efficiency benefits of the EAG in EEA operations. METHODS: Analysis of EEA operative videos from an EAG cohort (n = 20) and a control cohort (n = 20) was performed, assessing 12-minute segments in the first, middle, and last third of each operation. The first segment in each cohort was selected before EAG placement, serving as an internal control. Every endoscope lens soiling instance was counted (measured as cleaning actions per minute), timed (obscuration time %), and identified as a withdrawal, irrigation, or other cleaning action. Perioperative variables including skull base repair and postoperative cerebrospinal fluid leakage were assessed. RESULTS: Within the EAG cohort, obscuration time was reduced in the middle and last third compared with the first third (3.73% [CI: 2.39-5.07] vs 12.97% [CI: 10.24-15.70], P < .001; 4.19% [CI: 2.83-5.55] vs 12.97% [CI: 10.24-15.70], P < .001) and cleaning actions were also significantly reduced by EAG (0.69/min [CI: 0.39-0.99] vs 1.67/min [CI: 1.34-2.00], P = .001; 0.66/min [CI: 0.35-0.97] vs 1.67/min [CI: 1.34-2.00], P < .001). Between the control and EAG cohorts, there was no significant difference between obscuration time and cleaning actions in the first third (9.33% vs 12.97%, P = .086; 1.34/min vs 1.67/min, P = .151) or in the middle third (6.24% vs 3.73%, P = .140; 0.80/min vs 0.69/min, P = .335), but there was a significant difference in the last third (9.25% [CI: 6.95-11.55] vs 4.19% [CI: 2.83-5.55], P < .001; 0.95/min [CI: 0.73-1.17] vs 0.66/min [CI: 0.35-0.97], P = .018). CONCLUSION: EAG significantly reduces lens obscurations and cleaning events, particularly during the intradural portion of operations. This technology may offer a greater time-saving impact with patients undergoing long EEA operations.

2.
Nat Protoc ; 18(12): 3690-3731, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37989764

ABSTRACT

Non-negative matrix factorization (NMF) is an unsupervised learning method well suited to high-throughput biology. However, inferring biological processes from an NMF result still requires additional post hoc statistics and annotation for interpretation of learned features. Here, we introduce a suite of computational tools that implement NMF and provide methods for accurate and clear biological interpretation and analysis. A generalized discussion of NMF covering its benefits, limitations and open questions is followed by four procedures for the Bayesian NMF algorithm Coordinated Gene Activity across Pattern Subsets (CoGAPS). Each procedure will demonstrate NMF analysis to quantify cell state transitions in a public domain single-cell RNA-sequencing dataset. The first demonstrates PyCoGAPS, our new Python implementation that enhances runtime for large datasets, and the second allows its deployment in Docker. The third procedure steps through the same single-cell NMF analysis using our R CoGAPS interface. The fourth introduces a beginner-friendly CoGAPS platform using GenePattern Notebook, aimed at users with a working conceptual knowledge of data analysis but without a basic proficiency in the R or Python programming language. We also constructed a user-facing website to serve as a central repository for information and instructional materials about CoGAPS and its application programming interfaces. The expected timing to setup the packages and conduct a test run is around 15 min, and an additional 30 min to conduct analyses on a precomputed result. The expected runtime on the user's desired dataset can vary from hours to days depending on factors such as dataset size or input parameters.


Subject(s)
Algorithms , Programming Languages , Bayes Theorem , Single-Cell Analysis
3.
Nat Commun ; 14(1): 1748, 2023 03 29.
Article in English | MEDLINE | ID: mdl-36991011

ABSTRACT

Ketamine produces antidepressant effects in patients with treatment-resistant depression, but its usefulness is limited by its psychotropic side effects. Ketamine is thought to act via NMDA receptors and HCN1 channels to produce brain oscillations that are related to these effects. Using human intracranial recordings, we found that ketamine produces gamma oscillations in prefrontal cortex and hippocampus, structures previously implicated in ketamine's antidepressant effects, and a 3 Hz oscillation in posteromedial cortex, previously proposed as a mechanism for its dissociative effects. We analyzed oscillatory changes after subsequent propofol administration, whose GABAergic activity antagonizes ketamine's NMDA-mediated disinhibition, alongside a shared HCN1 inhibitory effect, to identify dynamics attributable to NMDA-mediated disinhibition versus HCN1 inhibition. Our results suggest that ketamine engages different neural circuits in distinct frequency-dependent patterns of activity to produce its antidepressant and dissociative sensory effects. These insights may help guide the development of brain dynamic biomarkers and novel therapeutics for depression.


Subject(s)
Ketamine , Propofol , Humans , Ketamine/pharmacology , Ketamine/therapeutic use , Propofol/pharmacology , N-Methylaspartate , Neurophysiology , Antidepressive Agents/pharmacology , Antidepressive Agents/therapeutic use , Cerebral Cortex/metabolism , Receptors, N-Methyl-D-Aspartate/metabolism
4.
Proc Natl Acad Sci U S A ; 120(11): e2207831120, 2023 03 14.
Article in English | MEDLINE | ID: mdl-36897972

ABSTRACT

During propofol-induced general anesthesia, alpha rhythms measured using electroencephalography undergo a striking shift from posterior to anterior, termed anteriorization, where the ubiquitous waking alpha is lost and a frontal alpha emerges. The functional significance of alpha anteriorization and the precise brain regions contributing to the phenomenon are a mystery. While posterior alpha is thought to be generated by thalamocortical circuits connecting nuclei of the sensory thalamus with their cortical partners, the thalamic origins of the propofol-induced alpha remain poorly understood. Here, we used human intracranial recordings to identify regions in sensory cortices where propofol attenuates a coherent alpha network, distinct from those in the frontal cortex where it amplifies coherent alpha and beta activities. We then performed diffusion tractography between these identified regions and individual thalamic nuclei to show that the opposing dynamics of anteriorization occur within two distinct thalamocortical networks. We found that propofol disrupted a posterior alpha network structurally connected with nuclei in the sensory and sensory associational regions of the thalamus. At the same time, propofol induced a coherent alpha oscillation within prefrontal cortical areas that were connected with thalamic nuclei involved in cognition, such as the mediodorsal nucleus. The cortical and thalamic anatomy involved, as well as their known functional roles, suggests multiple means by which propofol dismantles sensory and cognitive processes to achieve loss of consciousness.


Subject(s)
Propofol , Humans , Propofol/pharmacology , Consciousness , Electroencephalography , Brain , Thalamus , Unconsciousness/chemically induced , Neural Pathways , Cerebral Cortex
5.
Neurobiol Dis ; 176: 105944, 2023 01.
Article in English | MEDLINE | ID: mdl-36493974

ABSTRACT

Many patients with autism spectrum disorders (ASD) show disturbances in their sleep/wake cycles, and they may be particularly vulnerable to the impact of circadian disruptors. We have previously shown that a 2-weeks exposure to dim light at night (DLaN) disrupts diurnal rhythms, increases repetitive behaviors and reduces social interactions in contactin-associated protein-like 2 knock out (Cntnap2 KO) mice. The deleterious effects of DLaN may be mediated by intrinsically photosensitive retinal ganglion cells (ipRGCs) expressing the photopigment melanopsin, which is maximally sensitive to blue light (480 nm). In this study, the usage of a light-emitting diode array enabled us to shift the spectral properties of the DLaN while keeping the intensity of the illumination at 10 lx. First, we confirmed that the short-wavelength enriched lighting produced strong acute suppression of locomotor activity (masking), robust light-induced phase shifts, and cFos expression in the suprachiasmatic nucleus in wild-type (WT) mice, while the long-wavelength enriched lighting evoked much weaker responses. Opn4DTA mice, lacking the melanopsin expressing ipRGCs, were resistant to DLaN effects. Importantly, shifting the DLaN stimulus to longer wavelengths mitigated the negative impact on the activity rhythms and 'autistic' behaviors (i.e. reciprocal social interactions, repetitive grooming) in the Cntnap2 KO as well as in WT mice. The short-, but not the long-wavelength enriched, DLaN triggered cFos expression in in the basolateral amygdala (BLA) as well as in the peri-habenula region raising that possibility that these cell populations may mediate the effects. Broadly, our findings are consistent with the recommendation that spectral properties of light at night should be considered to optimize health in neurotypical as well as vulnerable populations.


Subject(s)
Circadian Rhythm , Retinal Ganglion Cells , Mice , Animals , Circadian Rhythm/physiology , Retinal Ganglion Cells/metabolism , Suprachiasmatic Nucleus , Light , Membrane Proteins/metabolism , Nerve Tissue Proteins/metabolism
6.
Cortex ; 152: 136-152, 2022 07.
Article in English | MEDLINE | ID: mdl-35569326

ABSTRACT

Tools assaying the neural networks that modulate consciousness may facilitate tracking of recovery after acute severe brain injury. The ABCD framework classifies resting-state EEG into categories reflecting levels of thalamocortical network function that correlate with outcome in post-cardiac arrest coma. In this longitudinal cohort study, we applied the ABCD framework to 20 patients with acute severe traumatic brain injury requiring intensive care (12 of whom were also studied at ≥6-months post-injury) and 16 healthy controls. We tested four hypotheses: 1) EEG ABCD classifications are spatially heterogeneous and temporally variable; 2) ABCD classifications improve longitudinally, commensurate with the degree of behavioral recovery; 3) ABCD classifications correlate with behavioral level of consciousness; and 4) the Coma Recovery Scale-Revised arousal facilitation protocol yields improved ABCD classifications. Channel-level EEG power spectra were classified based on spectral peaks within pre-defined frequency bands: 'A' = no peaks above delta (<4 Hz) range (complete thalamocortical disruption); 'B' = theta (4-8 Hz) peak (severe thalamocortical disruption); 'C' = theta and beta (13-24 Hz) peaks (moderate thalamocortical disruption); or 'D' = alpha (8-13 Hz) and beta peaks (normal thalamocortical function). Acutely, 95% of patients demonstrated 'D' signals in at least one channel but exhibited within-session temporal variability and spatial heterogeneity in the proportion of different channel-level ABCD classifications. By contrast, healthy participants and patients at follow-up consistently demonstrated signals corresponding to intact thalamocortical network function. Patients demonstrated longitudinal improvement in ABCD classifications (p < .05) and ABCD classification distinguished patients with and without command-following in the subacute-to-chronic phase of recovery (p < .01). In patients studied acutely, ABCD classifications improved after the Coma Recovery Scale-Revised arousal facilitation protocol (p < .05) but did not correspond with behavioral level of consciousness. These findings support the use of the ABCD framework to characterize channel-level EEG dynamics and track fluctuations in functional thalamocortical network integrity in spatial detail.


Subject(s)
Brain Injuries, Traumatic , Brain Injuries , Coma , Electroencephalography , Humans , Longitudinal Studies
7.
Glycobiology ; 32(2): 136-147, 2022 03 19.
Article in English | MEDLINE | ID: mdl-34939104

ABSTRACT

Polysaccharide A (PSA) is the immunodominant capsular carbohydrate from the gram negative commensal microbe Bacteroides fragilis that has shown remarkable potency in ameliorating many rodent models of inflammatory disease by eliciting downstream suppressive CD4+ T cells. PSA is composed of a zwitterionic repeating unit that allows it to be processed by antigen presenting cells (APCs) and presented by MHCII in a glycosylation-dependent manner. While previous work has uncovered much about the interactions between MHCII and PSA, as well as the downstream T cell response, little is known about how PSA affects the phenotype of MHCII+ APCs, including macrophages. Here, we utilized an unbiased systems approach consisting of RNAseq transcriptomics, high-throughput flow cytometry, Luminex analysis and targeted validation experiments to characterize the impact of PSA-mediated stimulation of splenic MHCII+ cells. The data revealed that PSA potently elicited the upregulation of an alternatively activated M2 macrophage transcriptomic and cell surface signature. Cell-type-specific validation experiments further demonstrated that PSA-exposed bone marrow-derived macrophages (BMDMs) induced cell surface and intracellular markers associated with M2 macrophages compared with conventional peptide ovalbumin (ova)-exposed BMDMs. In contrast to macrophages, we also found that CD11c+ dendritic cells (DCs) upregulated the pro-T cell activation costimulatory molecule CD86 following PSA stimulation. Consistent with the divergent BMDM and DC changes, PSA-exposed DCs elicited an antigen-experienced T cell phenotype in co-cultures, whereas macrophages did not. These findings collectively demonstrate that the PSA-induced immune response is characterized by both T cell stimulation via presentation by DCs, and a previously unrecognized anti-inflammatory polarization of macrophages.


Subject(s)
Antigen-Presenting Cells , Prostate-Specific Antigen , Animals , Anti-Inflammatory Agents/metabolism , Antigen-Presenting Cells/metabolism , Dendritic Cells , Humans , Macrophages , Male , Mice , Mice, Inbred C57BL , Polysaccharides/metabolism , Prostate-Specific Antigen/metabolism
8.
PLoS One ; 16(12): e0259840, 2021.
Article in English | MEDLINE | ID: mdl-34855749

ABSTRACT

BACKGROUND: We investigated the effect of delirium burden in mechanically ventilated patients, beginning in the ICU and continuing throughout hospitalization, on functional neurologic outcomes up to 2.5 years following critical illness. METHODS: Prospective cohort study of enrolling 178 consecutive mechanically ventilated adult medical and surgical ICU patients between October 2013 and May 2016. Altogether, patients were assessed daily for delirium 2941days using the Confusion Assessment Method for the ICU (CAM-ICU). Hospitalization delirium burden (DB) was quantified as number of hospital days with delirium divided by total days at risk. Survival status up to 2.5 years and neurologic outcomes using the Glasgow Outcome Scale were recorded at discharge 3, 6, and 12 months post-discharge. RESULTS: Of 178 patients, 19 (10.7%) were excluded from outcome analyses due to persistent coma. Among the remaining 159, 123 (77.4%) experienced delirium. DB was independently associated with >4-fold increased mortality at 2.5 years following ICU admission (adjusted hazard ratio [aHR], 4.77; 95% CI, 2.10-10.83; P < .001), and worse neurologic outcome at discharge (adjusted odds ratio [aOR], 0.02; 0.01-0.09; P < .001), 3 (aOR, 0.11; 0.04-0.31; P < .001), 6 (aOR, 0.10; 0.04-0.29; P < .001), and 12 months (aOR, 0.19; 0.07-0.52; P = .001). DB in the ICU alone was not associated with mortality (HR, 1.79; 0.93-3.44; P = .082) and predicted neurologic outcome less strongly than entire hospital stay DB. Similarly, the number of delirium days in the ICU and for whole hospitalization were not associated with mortality (HR, 1.00; 0.93-1.08; P = .917 and HR, 0.98; 0.94-1.03, P = .535) nor with neurological outcomes, except for the association between ICU delirium days and neurological outcome at discharge (OR, 0.90; 0.81-0.99, P = .038). CONCLUSIONS: Delirium burden throughout hospitalization independently predicts long term neurologic outcomes and death up to 2.5 years after critical illness, and is more predictive than delirium burden in the ICU alone and number of delirium days.


Subject(s)
Delirium/mortality , Delirium/physiopathology , Intensive Care Units , Aged , Analgesics/therapeutic use , Coma/mortality , Coma/physiopathology , Critical Illness/mortality , Female , Follow-Up Studies , Humans , Hypnotics and Sedatives/therapeutic use , Length of Stay , Male , Middle Aged , Nervous System Diseases/etiology , Prevalence , Prospective Studies , Respiration, Artificial
9.
N Z Med J ; 134(1544): 35-48, 2021 10 22.
Article in English | MEDLINE | ID: mdl-34695091

ABSTRACT

AIM: To explore patients' experiences of virtual consultations during the COVID-19 Alert Level 4 lockdown in New Zealand. METHOD: A single-practice retrospective phone survey exploring patients' satisfaction with the phone consultation process during Alert Level 4 lockdown. RESULTS: Of 259 eligible patients, 108 (42%) participated in the survey. Overall satisfaction with phone consultations was high, with a median score 9 out of 10 (95% CI 9-9). Participants were highly likely to recommend phone consultations to others, with a median score of 9 (95% CI 7-9). This was consistent across age groups, ethnicities and socioeconomic groupings. Men were less satisfied with phone consultations than women, with a 2 point (95% CI -3--1) lower median score than women, but they were not less likely to recommend phone consultations. Most participants found phone consultations to be convenient and time-saving and considered not seeing the doctor to be acceptable in the context of the lockdown. Few participants experienced technical difficulties over the phone. Issues of communication and appropriateness of consultations to the medium of the phone were raised. CONCLUSION: This single-centre study demonstrates the acceptability of phone consults for most patients presenting to general practice during a pandemic. These findings need further exploration in broader general practice settings and non-pandemic contexts.


Subject(s)
COVID-19 , General Practice , Patient Satisfaction/statistics & numerical data , Telemedicine , Adolescent , Adult , Aged , Aged, 80 and over , Communication , Female , Humans , Male , Middle Aged , New Zealand , Quarantine , Retrospective Studies , Surveys and Questionnaires , Telephone
10.
PLoS One ; 16(5): e0246165, 2021.
Article in English | MEDLINE | ID: mdl-33956800

ABSTRACT

In current anesthesiology practice, anesthesiologists infer the state of unconsciousness without directly monitoring the brain. Drug- and patient-specific electroencephalographic (EEG) signatures of anesthesia-induced unconsciousness have been identified previously. We applied machine learning approaches to construct classification models for real-time tracking of unconscious state during anesthesia-induced unconsciousness. We used cross-validation to select and train the best performing models using 33,159 2s segments of EEG data recorded from 7 healthy volunteers who received increasing infusions of propofol while responding to stimuli to directly assess unconsciousness. Cross-validated models of unconsciousness performed very well when tested on 13,929 2s EEG segments from 3 left-out volunteers collected under the same conditions (median volunteer AUCs 0.99-0.99). Models showed strong generalization when tested on a cohort of 27 surgical patients receiving solely propofol collected in a separate clinical dataset under different circumstances and using different hardware (median patient AUCs 0.95-0.98), with model predictions corresponding with actions taken by the anesthesiologist during the cases. Performance was also strong for 17 patients receiving sevoflurane (alone or in addition to propofol) (median AUCs 0.88-0.92). These results indicate that EEG spectral features can predict unconsciousness, even when tested on a different anesthetic that acts with a similar neural mechanism. With high performance predictions of unconsciousness, we can accurately monitor anesthetic state, and this approach may be used to engineer infusion pumps to intelligibly respond to patients' neural activity.


Subject(s)
Electroencephalography , Machine Learning , Signal Processing, Computer-Assisted , Unconsciousness/physiopathology , Anesthetics, Intravenous/pharmacology , Brain/drug effects , Brain/physiopathology , Electroencephalography/drug effects , Humans , Male , Sevoflurane/adverse effects , Unconsciousness/chemically induced
11.
Neurocrit Care ; 33(2): 364-375, 2020 10.
Article in English | MEDLINE | ID: mdl-32794142

ABSTRACT

There are currently no therapies proven to promote early recovery of consciousness in patients with severe brain injuries in the intensive care unit (ICU). For patients whose families face time-sensitive, life-or-death decisions, treatments that promote recovery of consciousness are needed to reduce the likelihood of premature withdrawal of life-sustaining therapy, facilitate autonomous self-expression, and increase access to rehabilitative care. Here, we present the Connectome-based Clinical Trial Platform (CCTP), a new paradigm for developing and testing targeted therapies that promote early recovery of consciousness in the ICU. We report the protocol for STIMPACT (Stimulant Therapy Targeted to Individualized Connectivity Maps to Promote ReACTivation of Consciousness), a CCTP-based trial in which intravenous methylphenidate will be used for targeted stimulation of dopaminergic circuits within the subcortical ascending arousal network (ClinicalTrials.gov NCT03814356). The scientific premise of the CCTP and the STIMPACT trial is that personalized brain network mapping in the ICU can identify patients whose connectomes are amenable to neuromodulation. Phase 1 of the STIMPACT trial is an open-label, safety and dose-finding study in 22 patients with disorders of consciousness caused by acute severe traumatic brain injury. Patients in Phase 1 will receive escalating daily doses (0.5-2.0 mg/kg) of intravenous methylphenidate over a 4-day period and will undergo resting-state functional magnetic resonance imaging and electroencephalography to evaluate the drug's pharmacodynamic properties. The primary outcome measure for Phase 1 relates to safety: the number of drug-related adverse events at each dose. Secondary outcome measures pertain to pharmacokinetics and pharmacodynamics: (1) time to maximal serum concentration; (2) serum half-life; (3) effect of the highest tolerated dose on resting-state functional MRI biomarkers of connectivity; and (4) effect of each dose on EEG biomarkers of cerebral cortical function. Predetermined safety and pharmacodynamic criteria must be fulfilled in Phase 1 to proceed to Phase 2A. Pharmacokinetic data from Phase 1 will also inform the study design of Phase 2A, where we will test the hypothesis that personalized connectome maps predict therapeutic responses to intravenous methylphenidate. Likewise, findings from Phase 2A will inform the design of Phase 2B, where we plan to enroll patients based on their personalized connectome maps. By selecting patients for clinical trials based on a principled, mechanistic assessment of their neuroanatomic potential for a therapeutic response, the CCTP paradigm and the STIMPACT trial have the potential to transform the therapeutic landscape in the ICU and improve outcomes for patients with severe brain injuries.


Subject(s)
Brain Injuries, Traumatic , Brain Injuries , Connectome , Consciousness , Humans , Intensive Care Units , Treatment Outcome
12.
Cell Mol Gastroenterol Hepatol ; 10(4): 729-746, 2020.
Article in English | MEDLINE | ID: mdl-32497792

ABSTRACT

BACKGROUND & AIMS: Vitamin D exerts regulatory roles via vitamin D receptor (VDR) in mucosal immunity, host defense, and inflammation involving host factors and microbiome. Human Vdr gene variation shapes the microbiome and VDR deletion leads to dysbiosis. Low VDR expression and diminished vitamin D/VDR signaling are observed in colon cancer. Nevertheless, how intestinal epithelial VDR is involved in tumorigenesis through gut microbiota remains unknown. We hypothesized that intestinal VDR protects mice against dysbiosis via modulating the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) pathway in tumorigenesis. METHODS: To test our hypothesis, we used an azoxymethane/dextran sulfate sodium-induced cancer model in intestinal VDR conditional knockout (VDRΔIEC) mice, cell cultures, stem cell-derived colonoids, and human colon cancer samples. RESULTS: VDRΔIEC mice have higher numbers of tumors, with the location shifted from the distal to proximal colon. Fecal microbiota analysis showed that VDR deletion leads to a bacterial profile shift from normal to susceptible carcinogenesis. We found enhanced bacterial staining in mouse and human tumors. Microbial metabolites from VDRΔIEC mice showed increased secondary bile acids, consistent with observations in human CRC. We further identified that VDR protein bound to the Jak2 promoter, suggesting that VDR transcriptionally regulated Jak2. The JAK/STAT pathway is critical in intestinal and microbial homeostasis. Fecal samples from VDRΔIEC mice activate the STAT3 signaling in human and mouse organoids. Lack of VDR led to hyperfunction of Jak2 in response to intestinal dysbiosis. A JAK/STAT inhibitor abolished the microbiome-induced activation of STAT3. CONCLUSIONS: We provide insights into the mechanism of VDR dysfunction leading to dysbiosis and tumorigenesis. It indicates a new target: microbiome and VDR for the prevention of cancer.


Subject(s)
Carcinogenesis/metabolism , Colonic Neoplasms/metabolism , Dysbiosis/metabolism , Receptors, Calcitriol/metabolism , Aged , Animals , Carcinogenesis/genetics , Carcinogenesis/pathology , Colonic Neoplasms/genetics , Colonic Neoplasms/pathology , Dysbiosis/genetics , Dysbiosis/pathology , Female , HCT116 Cells , Humans , Intestines/pathology , Janus Kinases/metabolism , Male , Mice, Inbred C57BL , Middle Aged , Protective Factors , Receptors, Calcitriol/genetics , STAT Transcription Factors/metabolism , Signal Transduction
13.
Biochim Biophys Acta Mol Cell Res ; 1867(9): 118734, 2020 09.
Article in English | MEDLINE | ID: mdl-32389645

ABSTRACT

A human cDNA encoding the LIM domain containing 194 amino acid cysteine and glycine rich protein 3 (CSRP3) was identified as a BAX suppressor in yeast and a pro-survival sequence that abrogated copper mediated regulated cell death (RCD). Yeast lacks a CSRP3 orthologue but it has four LIM sequences, namely RGA1, RGA2, LRG1 and PXL1. These are known regulators of stress responses yet their roles in RCD remain unknown. Given that LIMs interact with other LIMs, we ruled out the possibility that overexpressed yeast LIMs alone could prevent RCD and that CSRP3 functions by acting as a dominant regulator of yeast LIMs. Of interest was the discovery that even though yeast cells lacking the LIM encoding PXL1 had no overt growth defect, it was nevertheless supersensitive to the effects of sublethal levels of copper. Heterologous expression of human CSPR3 as well as the pro-survival 14-3-3 sequence corrected this copper supersensitivity. These results show that the pxl1∆-copper synthetic lethality is likely due to the induction of RCD. This differs from the prevailing model in which synthetic lethality occurs because of specific defects generated by the combined loss of two overlapping but non-essential functions.


Subject(s)
Cell Survival/genetics , Synthetic Lethal Mutations , Adaptor Proteins, Signal Transducing/metabolism , Apoptosis , Autophagy , Humans , LIM Domain Proteins/chemistry , LIM Domain Proteins/genetics , LIM Domain Proteins/metabolism , Models, Biological , Muscle Proteins/chemistry , Muscle Proteins/genetics , Muscle Proteins/metabolism , Protein Binding , Protein Interaction Domains and Motifs , Reactive Oxygen Species/metabolism , Saccharomyces cerevisiae/genetics , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/metabolism , bcl-2-Associated X Protein/metabolism
14.
NPJ Digit Med ; 2: 89, 2019.
Article in English | MEDLINE | ID: mdl-31508499

ABSTRACT

Over- and under-sedation are common in the ICU, and contribute to poor ICU outcomes including delirium. Behavioral assessments, such as Richmond Agitation-Sedation Scale (RASS) for monitoring levels of sedation and Confusion Assessment Method for the ICU (CAM-ICU) for detecting signs of delirium, are often used. As an alternative, brain monitoring with electroencephalography (EEG) has been proposed in the operating room, but is challenging to implement in ICU due to the differences between critical illness and elective surgery, as well as the duration of sedation. Here we present a deep learning model based on a combination of convolutional and recurrent neural networks that automatically tracks both the level of consciousness and delirium using frontal EEG signals in the ICU. For level of consciousness, the system achieves a median accuracy of 70% when allowing prediction to be within one RASS level difference across all patients, which is comparable or higher than the median technician-nurse agreement at 59%. For delirium, the system achieves an AUC of 0.80 with 69% sensitivity and 83% specificity at the optimal operating point. The results show it is feasible to continuously track level of consciousness and delirium in the ICU.

15.
Biochim Biophys Acta Mol Cell Res ; 1866(5): 773-792, 2019 05.
Article in English | MEDLINE | ID: mdl-30716408

ABSTRACT

Alterations in the levels of numerous second messengers are ubiquitous responses to all stresses that lead to apoptotic or hormetic responses. The sheer number and vast diversity of different second messenger systems activated in response to stresses belies a complexity that is often overlooked. This negligence is in large part due to the excessive focus on classical stress responsive second messenger mediators of stress especially Reactive Oxygen Species (ROS) but also others like calcium and ceramide. Here we review the many different intracellular second messengers that are involved in stress responses. We further integrate this information to emphasize that initial stress mediated responses consist of increased levels of a multitude of intracellular second messengers that serve to elicit the appropriate cell survival and/or cell death responses. We suggest that a greater focus on second messenger systems may shed more light on the processes that serve in the initiation of stress mediated PCD.


Subject(s)
Apoptosis/physiology , Calcium Signaling/physiology , Calcium/metabolism , Oxidative Stress/physiology , Reactive Oxygen Species/metabolism , Animals , Humans
16.
Inflamm Bowel Dis ; 25(1): 97-110, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30289450

ABSTRACT

Background: Vitamin D3 and vitamin D receptor (VDR) are involved in the pathogenesis of inflammatory bowel disease (IBD) and bacterial infection. Claudin-2 is a junction protein that mediates paracellular water transport in epithelia. Elevation of Claudin-2 is associated with active IBD. However, VDR involved in epithelial junctions under inflammation and infection remains largely unknown. We investigated the mechanisms on how VDR and Claudin-2 are related in inflamed states. Methods: Using cultured VDR-/- enteroids, human intestinal epithelial cells, VDR-/- mice with Salmonella- or DSS-colitis, and human IBD samples, we investigated the mechanisms how VDR and Claudin-2 are related in inflamed states. Results: After Salmonella infection had taken place, we observed significantly enhanced Claudin-2 and an increased bacterial invasion and translocation. A lack of VDR regulation led to a robust increase of Claudin-2 at the mRNA and protein levels post-infection. In DSS-treated VDR-/- mice, Claudin-2 was significantly increased. Location and quantification of Claudin-2 protein in the mouse colons treated with DSS also confirmed these results. Inflammatory cytokines were significantly higher in the serum and mRNA levels in intestine, which are known to increase Claudin-2. Furthermore, in inflamed intestine of ulcerative colitis patients, VDR expression was low and Claudin-2 was enhanced. Mechanistically, we identified the enhanced Claudin-2 promoter activity through the binding sites of NF-κB and STAT in inflamed VDR-/- cells. Conclusions: Our studies have identified a new role for intestinal epithelial VDR in regulating barrier functions in the context of infection and inflammation.


Subject(s)
Claudin-2/metabolism , Colitis, Ulcerative/immunology , Colitis/immunology , Epithelial Cells/immunology , Inflammation/immunology , Intestinal Mucosa/immunology , Receptors, Calcitriol/physiology , Adult , Aged , Aged, 80 and over , Animals , Case-Control Studies , Cohort Studies , Colitis/chemically induced , Colitis/microbiology , Colitis/pathology , Colitis, Ulcerative/metabolism , Colitis, Ulcerative/microbiology , Colitis, Ulcerative/pathology , Epithelial Cells/metabolism , Epithelial Cells/microbiology , Epithelial Cells/pathology , Female , Follow-Up Studies , Humans , Inflammation/metabolism , Inflammation/microbiology , Inflammation/pathology , Intestinal Mucosa/metabolism , Intestinal Mucosa/microbiology , Intestinal Mucosa/pathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Prognosis , Salmonella/immunology , Salmonella Infections/complications , Salmonella Infections/microbiology
17.
Biochim Biophys Acta Mol Cell Res ; 1866(4): 699-712, 2019 04.
Article in English | MEDLINE | ID: mdl-30529230

ABSTRACT

The prevailing models of stress induced Programmed Cell Death (PCD) posit that excess extracellular chemicals interact with or enter cells and disrupts cellular homeostasis. This activates signalling cascades involving the mitochondria, an increase in the steady state levels of Reactive Oxygen Species (ROS) as well as the activation of Bax and caspases. Further, the increased ROS also causes cellular damage that triggers or enhances PCD responses. The models have been modified in a number of ways, for example to include the existence of caspase and Bax independent forms of PCD. More recently, the ubiquity of ROS has also been challenged in part based on the failure of anti-oxidants to protect from diseases with increased intensity of oxidative stress. Here we focus on a number of other, often overlooked, observations regarding stress mediated responses that may further increase our mechanistic understanding of PCD. These include the concept of the "milieu intérieur" which suggests that cells actively protect themselves (adaptive homeostasis) in part by limiting entry to most extracellular chemicals. Of similar importance, stress also increases the levels of other stress inducible second messengers including ceramide, iron and calcium. This review focuses on the concept that stress is an agonist that conveys information that is transduced into the cell to activate the appropriate genetically encoded cell death and survival responses.


Subject(s)
Apoptosis , Stress, Physiological , Cell Survival/genetics , Homeostasis , Reactive Oxygen Species/metabolism , Signal Transduction
18.
J Comput Chem ; 39(30): 2494-2507, 2018 11 15.
Article in English | MEDLINE | ID: mdl-30368845

ABSTRACT

We present osprey 3.0, a new and greatly improved release of the osprey protein design software. Osprey 3.0 features a convenient new Python interface, which greatly improves its ease of use. It is over two orders of magnitude faster than previous versions of osprey when running the same algorithms on the same hardware. Moreover, osprey 3.0 includes several new algorithms, which introduce substantial speedups as well as improved biophysical modeling. It also includes GPU support, which provides an additional speedup of over an order of magnitude. Like previous versions of osprey, osprey 3.0 offers a unique package of advantages over other design software, including provable design algorithms that account for continuous flexibility during design and model conformational entropy. Finally, we show here empirically that osprey 3.0 accurately predicts the effect of mutations on protein-protein binding. Osprey 3.0 is available at http://www.cs.duke.edu/donaldlab/osprey.php as free and open-source software. © 2018 Wiley Periodicals, Inc.


Subject(s)
Protein Conformation , Proteins/chemistry , Software , Algorithms , Models, Molecular , Protein Binding
19.
Front Syst Neurosci ; 12: 23, 2018.
Article in English | MEDLINE | ID: mdl-29988455

ABSTRACT

Patients with autism spectrum disorder (ASD) often require sedation or general anesthesia. ASD is thought to arise from deficits in GABAergic signaling leading to abnormal neurodevelopment. We sought to investigate differences in how ASD patients respond to the GABAergic drug propofol by comparing the propofol-induced electroencephalogram (EEG) of ASD and neurotypical (NT) patients. This investigation was a prospective observational study. Continuous 4-channel frontal EEG was recorded during routine anesthetic care of patients undergoing endoscopic procedures between July 1, 2014 and May 1, 2016. Study patients were defined as those with previously diagnosed ASD by DSM-V criteria, aged 2-30 years old. NT patients were defined as those lacking neurological or psychiatric abnormalities, aged 2-30 years old. The primary outcome was changes in propofol-induced alpha (8-13 Hz) and slow (0.1-1 Hz) oscillation power by age. A post hoc analysis was performed to characterize incidence of burst suppression during propofol anesthesia. The primary risk factor of interest was a prior diagnosis of ASD. Outcomes were compared between ASD and NT patients using Bayesian methods. Compared to NT patients, slow oscillation power was initially higher in ASD patients (17.05 vs. 14.20 dB at 2.33 years), but progressively declined with age (11.56 vs. 13.95 dB at 22.5 years). Frontal alpha power was initially lower in ASD patients (17.65 vs. 18.86 dB at 5.42 years) and continued to decline with age (6.37 vs. 11.89 dB at 22.5 years). The incidence of burst suppression was significantly higher in ASD vs. NT patients (23.0% vs. 12.2%, p < 0.01) despite reduced total propofol dosing in ASD patients. Ultimately, we found that ASD patients respond differently to propofol compared to NT patients. A similar pattern of decreased alpha power and increased sensitivity to burst suppression develops in older NT adults; one interpretation of our data could be that ASD patients undergo a form of accelerated neuronal aging in adolescence. Our results suggest that investigations of the propofol-induced EEG in ASD patients may enable insights into the underlying differences in neural circuitry of ASD and yield safer practices for managing patients with ASD.

20.
IEEE Trans Biomed Eng ; 65(12): 2684-2691, 2018 12.
Article in English | MEDLINE | ID: mdl-29993386

ABSTRACT

OBJECTIVE: This study was performed to evaluate how well states of deep sedation in ICU patients can be detected from the frontal electroencephalogram (EEG) using features based on the method of atomic decomposition (AD). METHODS: We analyzed a clinical dataset of 20 min of EEG recordings per patient from 44 mechanically ventilated adult patients receiving sedatives in an intensive care unit (ICU) setting. Several features derived from AD of the EEG signal were used to discriminate between awake and sedated states. We trained support vector machine (SVM) classifiers using AD features and compared the classification performance with SVM classifiers trained using standard spectral and entropy features using leave-one-subject-out validation. The potential of each feature to discriminate between awake and sedated states was quantified using area under the receiver operating characteristic curve (AUC). RESULTS: The sedation level classification system using AD was able to reliably discriminate between sedated and awake states achieving an average AUC of 0.90, which was significantly better () than performance achieved using spectral (AUC = 0.86) and entropy (AUC = 0.81) domain features. A combined feature set consisting of AD, entropy, and spectral features provided better discrimination (AUC = 0.91, ) than any individual feature set. CONCLUSIONS: Features derived from the atomic decomposition of EEG signals provide useful discriminative information about the depth of sedation in ICU patients. SIGNIFICANCE: With further refinement and external validation, the proposed system may be able to assist clinical staff with continuous surveillance of sedation levels in mechanically ventilated critically ill ICU patients.


Subject(s)
Consciousness/physiology , Critical Care/methods , Deep Sedation/methods , Electroencephalography/methods , Signal Processing, Computer-Assisted , Aged , Female , Humans , Intensive Care Units , Male , Middle Aged , Support Vector Machine
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