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1.
Genes Immun ; 25(3): 188-200, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38777826

RESUMO

Immune checkpoint therapies (ICT) for advanced solid tumors mark a new milestone in cancer therapy. Yet their efficacy is often limited by poor immunogenicity, attributed to inadequate priming and generation of antitumor T cells by dendritic cells (DCs). Identifying biomarkers to enhance DC functions in such tumors is thus crucial. Tissue Inhibitor of Metalloproteinases-1 (TIMP-1), recognized for its influence on immune cells, has an underexplored relationship with DCs. Our research reveals a correlation between high TIMP1 levels in metastatic melanoma and increased CD8 + T cell infiltration and survival. Network studies indicate a functional connection with HLA genes. Spatial transcriptomic analysis of a national melanoma cohort revealed that TIMP1 expression in immune compartments associates with an HLA-A/MHC-I peptide loading signature in lymph nodes. Primary human and bone-marrow-derived DCs secrete TIMP-1, which notably increases MHC-I expression in classical type 1 dendritic cells (cDC1), especially under melanoma antigen exposure. TIMP-1 affects the immunoproteasome/TAP complex, as seen by upregulated PSMB8 and TAP-1 levels of myeloid DCs. This study uncovers the role of TIMP-1 in DC-mediated immunogenicity with insights into CD8 + T cell activation, providing a foundation for mechanistic exploration and highlighting its potential as a new target for combinatorial immunotherapy to enhance ICT effectiveness.


Assuntos
Células Dendríticas , Melanoma , Inibidor Tecidual de Metaloproteinase-1 , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Humanos , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Melanoma/imunologia , Melanoma/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Células Mieloides/imunologia , Células Mieloides/metabolismo , Antígenos de Histocompatibilidade Classe I/metabolismo , Antígenos de Histocompatibilidade Classe I/imunologia , Antígenos de Histocompatibilidade Classe I/genética
2.
Int J Cancer ; 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38648387

RESUMO

Cutaneous squamous cell carcinoma (cSCC) is the most common metastatic skin cancer and the metastatic disease is associated with poor prognosis. Cancer-associated fibroblasts (CAFs) promote progression of cancer, but their role in cSCC is largely unknown. We examined the potential of CAF markers in the assessment of metastasis risk and prognosis of primary cSCC. We utilized multiplexed fluorescence immunohistochemistry for profiling CAF landscape in metastatic and non-metastatic primary human cSCCs, in metastases, and in premalignant epidermal lesions. Quantitative high-resolution image analysis was performed with two separate panels of antibodies for CAF markers and results were correlated with clinical and histopathological parameters including disease-specific mortality. Increased stromal expression of fibroblast activation protein (FAP), α-smooth muscle actin, and secreted protein acidic and rich in cysteine (SPARC) were associated with progression to invasive cSCC. Elevation of FAP and platelet-derived growth factor receptor-ß (PDGFRß) expression was associated with metastasis risk of primary cSCCs. High expression of PDGFRß and periostin correlated with poor prognosis. Multimarker combination defined CAF subset, PDGFRα-/PDGFRß+/FAP+, was associated with invasion and metastasis, and independently predicted poor disease-specific survival. These results identify high PDGFRß expression alone and multimarker combination PDGFRα-/PDGFRß+/FAP+ by CAFs as potential biomarkers for risk of metastasis and poor prognosis.

3.
Oncotarget ; 15: 106-116, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38329731

RESUMO

Selective tropomyosin receptor kinase (TRK) inhibitors are approved targeted therapies for patients with solid tumors harboring a neurotrophic tyrosine receptor kinase (NTRK) gene fusion. Country-specific estimates of NTRK gene fusion frequency, and knowledge on the characteristics of affected patients, are limited. We identified patients with histologically-confirmed papillary thyroid cancer (PTC) from Finland's Auria Biobank. TRK protein expression was determined by pan-TRK immunohistochemistry. Immuno-stained tumor samples were scored by a certified pathologist. Gene fusions and other co-occurring gene alterations were identified by next generation sequencing. Patient characteristics and vital status were determined from linked hospital electronic health records (EHRs). Patients were followed from 1 year before PTC diagnosis until death. 6/389 (1.5%) PTC patients had an NTRK gene fusion (all NTRK3); mean age 43.8 years (and none had comorbidities) at PTC diagnosis. Gene fusion partners were EML4 (n = 3), ETV6 (n = 2), and RBPMS (n = 1). Of 3/6 patients with complete EHRs, all received radioactive iodine ablation only and were alive at end of follow-up (median observation, 9.12 years). In conclusion, NTRK gene fusion is infrequent in patients with PTC. Linkage of biobank samples to EHRs is feasible in describing the characteristics and outcomes of patients with PTC and potentially other cancer types.


Assuntos
Bancos de Espécimes Biológicos , Receptores de Aminoácido , Neoplasias da Glândula Tireoide , Humanos , Adulto , Câncer Papilífero da Tireoide/genética , Finlândia , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide/genética , Fusão Gênica
4.
Br J Anaesth ; 131(2): 348-359, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37268445

RESUMO

BACKGROUND: Anaesthetic-induced unresponsiveness and non-rapid eye movement (NREM) sleep share common neural pathways and neurophysiological features. We hypothesised that these states bear resemblance also at the experiential level. METHODS: We compared, in a within-subject design, the prevalence and content of experiences in reports obtained after anaesthetic-induced unresponsiveness and NREM sleep. Healthy males (N=39) received dexmedetomidine (n=20) or propofol (n=19) in stepwise doses to induce unresponsiveness. Those rousable were interviewed and left unstimulated, and the procedure was repeated. Finally, the anaesthetic dose was increased 50%, and the participants were interviewed after recovery. The same participants (N=37) were also later interviewed after NREM sleep awakenings. RESULTS: Most subjects were rousable, with no difference between anaesthetic agents (P=0.480). Lower drug plasma concentrations were associated with being rousable for both dexmedetomidine (P=0.007) and propofol (P=0.002) but not with recall of experiences in either drug group (dexmedetomidine: P=0.543; propofol: P=0.460). Of the 76 and 73 interviews performed after anaesthetic-induced unresponsiveness and NREM sleep, 69.7% and 64.4% included experiences, respectively. Recall did not differ between anaesthetic-induced unresponsiveness and NREM sleep (P=0.581), or between dexmedetomidine and propofol in any of the three awakening rounds (P>0.05). Disconnected dream-like experiences (62.3% vs 51.1%; P=0.418) and memory incorporation of the research setting (88.7% vs 78.7%; P=0.204) were equally often present in anaesthesia and sleep interviews, respectively, whereas awareness, signifying connected consciousness, was rarely reported in either state. CONCLUSIONS: Anaesthetic-induced unresponsiveness and NREM sleep are characterised by disconnected conscious experiences with corresponding recall frequencies and content. CLINICAL TRIAL REGISTRATION: Clinical trial registration. This study was part of a larger study registered at ClinicalTrials.gov (NCT01889004).


Assuntos
Anestésicos , Dexmedetomidina , Propofol , Humanos , Masculino , Dexmedetomidina/efeitos adversos , Movimentos Oculares , Hipnóticos e Sedativos/efeitos adversos , Propofol/efeitos adversos , Sono
5.
J Neurosci ; 43(26): 4884-4895, 2023 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-37225435

RESUMO

Establishing the neural mechanisms responsible for the altered global states of consciousness during anesthesia and dissociating these from other drug-related effects remains a challenge in consciousness research. We investigated differences in brain activity between connectedness and disconnectedness by administering various anesthetics at concentrations designed to render 50% of the subjects unresponsive. One hundred and sixty healthy male subjects were randomized to receive either propofol (1.7 µg/ml; n = 40), dexmedetomidine (1.5 ng/ml; n = 40), sevoflurane (0.9% end-tidal; n = 40), S-ketamine (0.75 µg/ml; n = 20), or saline placebo (n = 20) for 60 min using target-controlled infusions or vaporizer with end-tidal monitoring. Disconnectedness was defined as unresponsiveness to verbal commands probed at 2.5-min intervals and unawareness of external events in a postanesthesia interview. High-resolution positron emission tomography (PET) was used to quantify regional cerebral metabolic rates of glucose (CMRglu) utilization. Contrasting scans where the subjects were classified as connected and responsive versus disconnected and unresponsive revealed that for all anesthetics, except S-ketamine, the level of thalamic activity differed between these states. A conjunction analysis across the propofol, dexmedetomidine and sevoflurane groups confirmed the thalamus as the primary structure where reduced metabolic activity was related to disconnectedness. Widespread cortical metabolic suppression was observed when these subjects, classified as either connected or disconnected, were compared with the placebo group, suggesting that these findings may represent necessary but alone insufficient mechanisms for the change in the state of consciousness.SIGNIFICANCE STATEMENT Experimental anesthesia is commonly used in the search for measures of brain function which could distinguish between global states of consciousness. However, most previous studies have not been designed to separate effects related to consciousness from other effects related to drug exposure. We employed a novel study design to disentangle these effects by exposing subjects to predefined EC50 doses of four commonly used anesthetics or saline placebo. We demonstrate that state-related effects are remarkably limited compared with the widespread cortical effects related to drug exposure. In particular, decreased thalamic activity was associated with disconnectedness with all used anesthetics except for S-ketamine.


Assuntos
Anestesia , Anestésicos Inalatórios , Dexmedetomidina , Ketamina , Propofol , Masculino , Humanos , Propofol/farmacologia , Sevoflurano/farmacologia , Ketamina/farmacologia , Dexmedetomidina/farmacologia , Anestésicos Inalatórios/farmacologia , Anestésicos Intravenosos
6.
PLoS One ; 17(9): e0272260, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36067162

RESUMO

PURPOSE: Advanced age-related macular degeneration (AAMD) risk is associated with rare complement Factor I (FI) genetic variants associated with low FI protein levels (termed 'Type 1'), but it is unclear how variant prevalences differ between AMD patients from different ethnicities. METHODS: Collective prevalence of Type 1 CFI rare variant genotypes were examined in four European AAMD datasets. Collective minor allele frequencies (MAFs) were sourced from the natural history study SCOPE, the UK Biobank, the International AMD Genomics Consortium (IAMDGC), and the Finnish Biobank Cooperative (FINBB), and compared to paired control MAFs or background population prevalence rates from the Genome Aggregation Database (gnomAD). Due to a lack of available genetic data in non-European AAMD, power calculations were undertaken to estimate the AAMD population sizes required to identify statistically significant association between Type 1 CFI rare variants and disease risk in different ethnicities, using gnomAD populations as controls. RESULTS: Type 1 CFI rare variants were enriched in all European AAMD cohorts, with odds ratios (ORs) ranging between 3.1 and 7.8, and a greater enrichment was observed in dry AMD from FINBB (OR 8.9, 95% CI 1.49-53.31). The lack of available non-European AAMD datasets prevented us exploring this relationship more globally, however a statistical association may be detectable by future sequencing studies that sample approximately 2,000 AAMD individuals from Ashkenazi Jewish and Latino/Admixed American ethnicities. CONCLUSIONS: The relationship between Type 1 CFI rare variants increasing odds of AAMD are well established in Europeans, however the lack of broader genetic data in AAMD has adverse implications for clinical development and future commercialisation strategies of targeted FI therapies in AAMD. These findings emphasise the importance of generating more diverse genetic data in AAMD to improve equity of access to new treatments and address the bias in health care.


Assuntos
Degeneração Macular , Polimorfismo de Nucleotídeo Único , Humanos , Fator I do Complemento/genética , Genótipo , Acessibilidade aos Serviços de Saúde , Degeneração Macular/epidemiologia , Degeneração Macular/genética , Degeneração Macular/metabolismo , Prevalência
8.
Ann Med ; 54(1): 244-252, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35037531

RESUMO

BACKGROUND: Changes in the incidence of melanoma in children and adolescents have been reported in Europe and in the USA in the recent decades. AIMS: The aim of this study was to examine the incidence of paediatric and adolescent melanomas in Finland in 1990-2014, and the associated clinical and histopathological characteristics to reveal temporal trends, such as changes in diagnostic sensitivity of Spitzoid melanomas. METHODS: Information on 122 patients diagnosed with cutaneous melanoma at 0-19 years of age in Finland in 1990-2014 were retrieved from the Finnish Cancer Registry. 73 primary melanoma archival samples were re-evaluated by two dermatopathologists to allow comparability over time. RESULTS: A 5.6% annual increase was observed in the incidence of melanoma among children and adolescents during the study period. Fifty-six tumours were confirmed as malignant melanomas in the re-evaluation. After correction for tumour misclassification in the Cancer Registry, the age-adjusted annual incidence was estimated to have increased from 1.4/1 000 000 in 1990-1994 to 5.8/1 000 000 in 2010-2014. The change in incidence was most prominent among adolescents and in Spitzoid melanoma subtype. Melanomas diagnosed 1990-2002 and 2003-2014 did not differ in terms of their clinicopathological characteristics or prognosis (hazard ratio for melanoma-related death 1.53, 95% CI 0.30 to 7.88). Spitzoid melanomas were diagnosed at a younger age, were of higher stage and had higher Clark level than other melanomas, yet the hazard ratio for death was 0.52 (95% CI 0.10 to 2.58) for Spitzoid versus other melanomas. CONCLUSIONS: The incidence of cutaneous melanoma has clearly increased among the young in Finland, especially among adolescents. No evidence for overdiagnosis of Spitzoid melanomas as the underlying cause of the increased incidence was observed.Key messageA nationwide retrospective re-evaluation of the cutaneous melanomas recorded in the Finnish Cancer Registry among patients aged 0-19 years in Finland in 1990-2014 revealed an approximately 4-fold increase in the incidence. The increase in the incidence was most prominent among adolescents and in the Spitzoid melanoma subtype. Our results contrast those reported in other countries, where the incidence of melanoma among adolescents has declined.


Assuntos
Melanoma , Nevo de Células Epitelioides e Fusiformes , Neoplasias Cutâneas , Adolescente , Adulto , Criança , Pré-Escolar , Finlândia/epidemiologia , Humanos , Incidência , Lactente , Recém-Nascido , Melanoma/diagnóstico , Melanoma/epidemiologia , Melanoma/patologia , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Adulto Jovem
9.
Eur J Anaesthesiol ; 39(6): 521-532, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534172

RESUMO

BACKGROUND: Pharmacometabolomics uses large-scale data capturing methods to uncover drug-induced shifts in the metabolic profile. The specific effects of anaesthetics on the human metabolome are largely unknown. OBJECTIVE: We aimed to discover whether exposure to routinely used anaesthetics have an acute effect on the human metabolic profile. DESIGN: Randomised, open-label, controlled, parallel group, phase IV clinical drug trial. SETTING: The study was conducted at Turku PET Centre, University of Turku, Finland, 2016 to 2017. PARTICIPANTS: One hundred and sixty healthy male volunteers were recruited. The metabolomic data of 159 were evaluable. INTERVENTIONS: Volunteers were randomised to receive a 1-h exposure to equipotent doses (EC50 for verbal command) of dexmedetomidine (1.5 ng ml-1; n  = 40), propofol (1.7 µg ml-1; n  = 40), sevoflurane (0.9% end-tidal; n  = 39), S-ketamine (0.75 µg ml-1; n  = 20) or placebo (n = 20). MAIN OUTCOME MEASURES: Metabolite subgroups of apolipoproteins and lipoproteins, cholesterol, glycerides and phospholipids, fatty acids, glycolysis, amino acids, ketone bodies, creatinine and albumin and the inflammatory marker GlycA, were analysed with nuclear magnetic resonance spectroscopy from arterial blood samples collected at baseline, after anaesthetic administration and 70 min post-anaesthesia. RESULTS: All metabolite subgroups were affected. Statistically significant changes vs. placebo were observed in 11.0, 41.3, 0.65 and 3.9% of the 155 analytes in the dexmedetomidine, propofol, sevoflurane and S-ketamine groups, respectively. Dexmedetomidine increased glucose, decreased ketone bodies and affected lipoproteins and apolipoproteins. Propofol altered lipoproteins, fatty acids, glycerides and phospholipids and slightly increased inflammatory marker glycoprotein acetylation. Sevoflurane was relatively inert. S-ketamine increased glucose and lactate, whereasbranched chain amino acids and tyrosine decreased. CONCLUSION: A 1-h exposure to moderate doses of routinely used anaesthetics led to significant and characteristic alterations in the metabolic profile. Dexmedetomidine-induced alterations mirror a2-adrenoceptor agonism. Propofol emulsion altered the lipid profile. The inertness of sevoflurane might prove useful in vulnerable patients. S-ketamine induced amino acid alterations might be linked to its suggested antidepressive properties. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT02624401.


Assuntos
Anestésicos Inalatórios , Dexmedetomidina , Metaboloma , Éteres Metílicos , Propofol , Aminoácidos , Anestésicos Inalatórios/efeitos adversos , Dexmedetomidina/efeitos adversos , Ácidos Graxos , Glucose , Glicerídeos , Humanos , Ketamina , Corpos Cetônicos , Espectroscopia de Ressonância Magnética , Masculino , Metaboloma/efeitos dos fármacos , Fosfolipídeos , Sevoflurano
10.
Conscious Cogn ; 96: 103239, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34801782

RESUMO

To understand how anesthetics with different molecular mechanisms affect consciousness, we explored subjective experiences recalled after responsive and unresponsive sedation induced with equisedative doses of dexmedetomidine, propofol, sevoflurane, and S-ketamine in healthy male participants (N = 140). The anesthetics were administered in experimental setting using target-controlled infusion or vapouriser for one hour. Interviews conducted after anesthetic administration revealed that 46.9% (n = 46) of arousable participants (n = 98) reported experiences, most frequently dreaming or memory incorporation of the setting. Participants receiving dexmedetomidine reported experiences most often while S-ketamine induced the most multimodal experiences. Responsiveness at the end of anesthetic administration did not affect the prevalence or content of reported experiences. These results demonstrate that subjective experiences during responsive and unresponsive sedation are common and anesthetic agents with different molecular mechanisms of action may have different effects on the prevalence and complexity of the experiences, albeit in the present sample the differences between drugs were minute.


Assuntos
Anestésicos , Dexmedetomidina , Propofol , Anestésicos/farmacologia , Dexmedetomidina/farmacologia , Humanos , Hipnóticos e Sedativos/farmacologia , Masculino , Propofol/farmacologia , Sevoflurano/farmacologia
11.
Nat Cell Biol ; 23(10): 1073-1084, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34616024

RESUMO

Spatially controlled, cargo-specific endocytosis is essential for development, tissue homeostasis and cancer invasion. Unlike cargo-specific clathrin-mediated endocytosis, the clathrin- and dynamin-independent endocytic pathway (CLIC-GEEC, CG pathway) is considered a bulk internalization route for the fluid phase, glycosylated membrane proteins and lipids. While the core molecular players of CG-endocytosis have been recently defined, evidence of cargo-specific adaptors or selective uptake of proteins for the pathway are lacking. Here we identify the actin-binding protein Swiprosin-1 (Swip1, EFHD2) as a cargo-specific adaptor for CG-endocytosis. Swip1 couples active Rab21-associated integrins with key components of the CG-endocytic machinery-Arf1, IRSp53 and actin-and is critical for integrin endocytosis. Through this function, Swip1 supports integrin-dependent cancer-cell migration and invasion, and is a negative prognostic marker in breast cancer. Our results demonstrate a previously unknown cargo selectivity for the CG pathway and a role for specific adaptors in recruitment into this endocytic route.


Assuntos
Neoplasias da Mama/patologia , Clatrina/metabolismo , Dinaminas/metabolismo , Endocitose , Integrina beta1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas rab de Ligação ao GTP/metabolismo , Actinas/metabolismo , Transporte Biológico , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Movimento Celular , Clatrina/genética , Dinaminas/genética , Feminino , Humanos , Integrina beta1/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , Proteínas rab de Ligação ao GTP/genética
12.
J Neurosci ; 41(8): 1769-1778, 2021 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-33372062

RESUMO

What happens in the brain when conscious awareness of the surrounding world fades? We manipulated consciousness in two experiments in a group of healthy males and measured brain activity with positron emission tomography. Measurements were made during wakefulness, escalating and constant levels of two anesthetic agents (experiment 1, n = 39), and during sleep-deprived wakefulness and non-rapid eye movement sleep (experiment 2, n = 37). In experiment 1, the subjects were randomized to receive either propofol or dexmedetomidine until unresponsiveness. In both experiments, forced awakenings were applied to achieve rapid recovery from an unresponsive to a responsive state, followed by immediate and detailed interviews of subjective experiences during the preceding unresponsive condition. Unresponsiveness rarely denoted unconsciousness, as the majority of the subjects had internally generated experiences. Unresponsive anesthetic states and verified sleep stages, where a subsequent report of mental content included no signs of awareness of the surrounding world, indicated a disconnected state. Functional brain imaging comparing responsive and connected versus unresponsive and disconnected states of consciousness during constant anesthetic exposure revealed that activity of the thalamus, cingulate cortices, and angular gyri are fundamental for human consciousness. These brain structures were affected independent from the pharmacologic agent, drug concentration, and direction of change in the state of consciousness. Analogous findings were obtained when consciousness was regulated by physiological sleep. State-specific findings were distinct and separable from the overall effects of the interventions, which included widespread depression of brain activity across cortical areas. These findings identify a central core brain network critical for human consciousness.SIGNIFICANCE STATEMENT Trying to understand the biological basis of human consciousness is currently one of the greatest challenges of neuroscience. While the loss and return of consciousness regulated by anesthetic drugs and physiological sleep are used as model systems in experimental studies on consciousness, previous research results have been confounded by drug effects, by confusing behavioral "unresponsiveness" and internally generated consciousness, and by comparing brain activity levels across states that differ in several other respects than only consciousness. Here, we present carefully designed studies that overcome many previous confounders and for the first time reveal the neural mechanisms underlying human consciousness and its disconnection from behavioral responsiveness, both during anesthesia and during normal sleep, and in the same study subjects.


Assuntos
Encéfalo/fisiologia , Estado de Consciência/fisiologia , Hipnóticos e Sedativos/farmacologia , Privação do Sono/fisiopatologia , Sono REM/fisiologia , Vigília/fisiologia , Adulto , Encéfalo/efeitos dos fármacos , Dexmedetomidina/farmacologia , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Propofol/farmacologia , Inconsciência/induzido quimicamente , Inconsciência/fisiopatologia
13.
Br J Anaesth ; 125(4): 518-528, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32773216

RESUMO

BACKGROUND: Coherent alpha electroencephalogram (EEG) rhythms in the frontal cortex have been correlated with the hypnotic effects of propofol and dexmedetomidine, but less is known about frontal connectivity as a state-specific correlate of unresponsiveness as compared with long-range connectivity. We aimed to distinguish dose- and state-dependent effects of dexmedetomidine and propofol on EEG connectivity. METHODS: Forty-seven healthy males received either dexmedetomidine (n=23) or propofol (n=24) as target-controlled infusion with stepwise increments until loss of responsiveness (LOR). We attempted to arouse participants during constant dosing (return of responsiveness [ROR]), and the target concentration was then increased 50% to achieve presumed loss of consciousness. We collected 64-channel EEG data and prefrontal-frontal and anterior-posterior functional connectivity in the alpha band (8-14 Hz) was measured using coherence and weighted phase lag index (wPLI). Directed connectivity was measured with directed phase lag index (dPLI). RESULTS: Prefrontal-frontal EEG-based connectivity discriminated the states at the different drug concentrations. At ROR, prefrontal-frontal connectivity reversed to the level observed before LOR, indicating that connectivity changes were related to unresponsiveness rather than drug concentration. Unresponsiveness was associated with emergence of frontal-to-prefrontal dominance (dPLI: -0.13 to -0.40) in contrast to baseline (dPLI: 0.01-0.02). Coherence, wPLI, and dPLI had similar capability to discriminate the states that differed in terms of responsiveness and drug concentration. In contrast, anterior-posterior connectivity in the alpha band did not differentiate LOR and ROR. CONCLUSIONS: Local prefrontal-frontal EEG-based connectivity reflects unresponsiveness induced by propofol or dexmedetomidine, suggesting its utility in monitoring the anaesthetised state with these agents. CLINICAL TRIAL REGISTRATION: NCT01889004.


Assuntos
Dexmedetomidina/farmacologia , Eletroencefalografia/efeitos dos fármacos , Propofol/farmacologia , Adulto , Relação Dose-Resposta a Droga , Lobo Frontal/efeitos dos fármacos , Lobo Frontal/fisiologia , Humanos , Masculino , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/fisiologia
14.
Int J Psychophysiol ; 144: 14-24, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31228496

RESUMO

There are several different approaches to analyze event-related potentials (ERPs) at single-subject level, and the aim of the current study is to provide information for choosing a method based on its ability to detect ERP effects and factors influencing the results. We used data from 79 healthy participants with EEG referenced to mastoid average and investigated the detection rate of auditory N400 effect in single-subject analysis using five methods: visual inspection of participant-wise averaged ERPs, analysis of variance (ANOVA) for amplitude averages in a time window, cluster-based non-parametric testing, a novel Bayesian approach and Studentized continuous wavelet transform (t-CWT). Visual inspection by three independent raters yielded N400 effect detection in 85% of the participants in at least one paradigm (active responding or passive listening), whereas ANOVA identified the effect in 68%, the cluster-method in 59%, the Bayesian method in 89%, and different versions of t-CWT in 22-59% of the participants. Thus, the Bayesian method was the most liberal and also showed the greatest concordance between the experimental paradigms (active/passive). ANOVA detected significant effect only in cases with converging evidence from other methods. The t-CWT and cluster-based method were the most conservative methods. As we show in the current study, different analysis methods provide results that do not completely overlap. The method of choice for determining the presence of an ERP component at single-subject level thus remains unresolved. Relying on a single statistical method may not be sufficient for drawing conclusions on single-subject ERPs.


Assuntos
Córtex Cerebral/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Estudos de Caso Único como Assunto , Adulto , Interpretação Estatística de Dados , Eletroencefalografia/normas , Humanos , Masculino , Adulto Jovem
15.
Anesthesiology ; 129(1): 22-36, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29642080

RESUMO

BACKGROUND: Differentiating drug-related changes and state-related changes on the electroencephalogram during anesthetic-induced unconsciousness has remained a challenge. To distinguish these, we designed a rigorous experimental protocol with two drugs known to have distinct molecular mechanisms of action. We hypothesized that drug- and state-related changes can be separated. METHODS: Forty-seven healthy participants were randomized to receive dexmedetomidine (n = 23) or propofol (n = 24) as target-controlled infusions until loss of responsiveness. Then, an attempt was made to arouse the participant to regain responsiveness while keeping the drug infusion constant. Finally, the concentration was increased 1.5-fold to achieve presumable loss of consciousness. We conducted statistical comparisons between the drugs and different states of consciousness for spectral bandwidths, and observed how drug-induced electroencephalogram patterns reversed upon awakening. Cross-frequency coupling was also analyzed between slow-wave phase and alpha power. RESULTS: Eighteen (78%) and 10 (42%) subjects were arousable during the constant drug infusion in the dexmedetomidine and propofol groups, respectively (P = 0.011 between the drugs). Corresponding with deepening anesthetic level, slow-wave power increased, and a state-dependent alpha anteriorization was detected with both drugs, especially with propofol. The slow-wave and frontal alpha activities were momentarily disrupted as the subjects regained responsiveness at awakening. Negative phase-amplitude coupling before and during loss of responsiveness frontally and positive coupling during the highest drug concentration posteriorly were observed in the propofol but not in the dexmedetomidine group. CONCLUSIONS: Electroencephalogram effects of dexmedetomidine and propofol are strongly drug- and state-dependent. Changes in slow-wave and alpha activity seemed to best detect different states of consciousness.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/administração & dosagem , Dexmedetomidina/administração & dosagem , Eletroencefalografia/efeitos dos fármacos , Hipnóticos e Sedativos/administração & dosagem , Propofol/administração & dosagem , Agonistas de Receptores Adrenérgicos alfa 2/sangue , Adulto , Anestésicos Intravenosos , Dexmedetomidina/sangue , Eletroencefalografia/métodos , Humanos , Hipnóticos e Sedativos/sangue , Infusões Intravenosas , Masculino , Propofol/sangue , Adulto Jovem
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