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1.
Mol Psychiatry ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671214

RESUMO

Formal thought disorder (FTD) is a clinical key factor in schizophrenia, but the neurobiological underpinnings remain unclear. In particular, the relationship between FTD symptom dimensions and patterns of regional brain volume loss in schizophrenia remains to be established in large cohorts. Even less is known about the cellular basis of FTD. Our study addresses these major obstacles by enrolling a large multi-site cohort acquired by the ENIGMA Schizophrenia Working Group (752 schizophrenia patients and 1256 controls), to unravel the neuroanatomy of FTD in schizophrenia and using virtual histology tools on implicated brain regions to investigate the cellular basis. Based on the findings of previous clinical and neuroimaging studies, we decided to separately explore positive, negative and total formal thought disorder. We used virtual histology tools to relate brain structural changes associated with FTD to cellular distributions in cortical regions. We identified distinct neural networks positive and negative FTD. Both networks encompassed fronto-occipito-amygdalar brain regions, but positive and negative FTD demonstrated a dissociation: negative FTD showed a relative sparing of orbitofrontal cortical thickness, while positive FTD also affected lateral temporal cortices. Virtual histology identified distinct transcriptomic fingerprints associated for both symptom dimensions. Negative FTD was linked to neuronal and astrocyte fingerprints, while positive FTD also showed associations with microglial cell types. These results provide an important step towards linking FTD to brain structural changes and their cellular underpinnings, providing an avenue for a better mechanistic understanding of this syndrome.

2.
Mol Psychiatry ; 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336840

RESUMO

Schizophrenia is a prototypical network disorder with widespread brain-morphological alterations, yet it remains unclear whether these distributed alterations robustly reflect the underlying network layout. We tested whether large-scale structural alterations in schizophrenia relate to normative structural and functional connectome architecture, and systematically evaluated robustness and generalizability of these network-level alterations. Leveraging anatomical MRI scans from 2439 adults with schizophrenia and 2867 healthy controls from 26 ENIGMA sites and normative data from the Human Connectome Project (n = 207), we evaluated structural alterations of schizophrenia against two network susceptibility models: (i) hub vulnerability, which examines associations between regional network centrality and magnitude of disease-related alterations; (ii) epicenter mapping, which identifies regions whose typical connectivity profile most closely resembles the disease-related morphological alterations. To assess generalizability and specificity, we contextualized the influence of site, disease stages, and individual clinical factors and compared network associations of schizophrenia with that found in affective disorders. Our findings show schizophrenia-related cortical thinning is spatially associated with functional and structural hubs, suggesting that highly interconnected regions are more vulnerable to morphological alterations. Predominantly temporo-paralimbic and frontal regions emerged as epicenters with connectivity profiles linked to schizophrenia's alteration patterns. Findings were robust across sites, disease stages, and related to individual symptoms. Moreover, transdiagnostic comparisons revealed overlapping epicenters in schizophrenia and bipolar, but not major depressive disorder, suggestive of a pathophysiological continuity within the schizophrenia-bipolar-spectrum. In sum, cortical alterations over the course of schizophrenia robustly follow brain network architecture, emphasizing marked hub susceptibility and temporo-frontal epicenters at both the level of the group and the individual. Subtle variations of epicenters across disease stages suggest interacting pathological processes, while associations with patient-specific symptoms support additional inter-individual variability of hub vulnerability and epicenters in schizophrenia. Our work outlines potential pathways to better understand macroscale structural alterations, and inter- individual variability in schizophrenia.

3.
Psychol Med ; 53(12): 5582-5591, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36047043

RESUMO

BACKGROUND: Coordination between the thalamus and cortex is necessary for efficient processing of sensory information and appears disrupted in schizophrenia. The significance of this disrupted coordination (i.e. thalamocortical dysconnectivity) to the symptoms and cognitive deficits of schizophrenia is unclear. It is also unknown whether similar dysconnectivity is observed in other forms of psychotic psychopathology and associated with familial risk for psychosis. Here we examine the relevance of thalamocortical connectivity to the clinical symptoms and cognition of patients with psychotic psychopathology, their first-degree biological relatives, and a group of healthy controls. METHOD: Patients with a schizophrenia-spectrum diagnosis (N = 100) or bipolar disorder with a history of psychosis (N = 33), their first-degree relatives (N = 73), and a group of healthy controls (N = 43) underwent resting functional MRI in addition to clinical and cognitive assessments as part of the Psychosis Human Connectome Project. A bilateral mediodorsal thalamus seed-based analysis was used to measure thalamocortical connectivity and test for group differences, as well as associations with symptomatology and cognition. RESULTS: Reduced connectivity from mediodorsal thalamus to insular, orbitofrontal, and cerebellar regions was seen in schizophrenia. Across groups, greater symptomatology was related to less thalamocortical connectivity to the left middle frontal gyrus, anterior cingulate, right insula, and cerebellum. Poorer cognition was related to less thalamocortical connectivity to bilateral insula. Analyses revealed similar patterns of dysconnectivity across patient groups and their relatives. CONCLUSIONS: Reduced thalamo-prefrontal-cerebellar and thalamo-insular connectivity may contribute to clinical symptomatology and cognitive deficits in patients with psychosis as well as individuals with familial risk for psychotic psychopathology.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Predisposição Genética para Doença , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Tálamo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Cognição , Vias Neurais
4.
J Med Internet Res ; 25: e48634, 2023 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-37955951

RESUMO

BACKGROUND: Impairments in cognition and motivation are core features of psychosis and strong predictors of social and occupational functioning. Accumulating evidence indicates that cognitive deficits in psychosis can be improved by computer-based cognitive training programs; however, barriers include access and adherence to cognitive training exercises. Limited evidence-based methods have been established to enhance motivated behavior. In this study, we tested the effects of web-based targeted cognitive and social cognitive training (TCT) delivered in conjunction with an innovative digital smartphone app called Personalized Real-Time Intervention for Motivational Enhancement (PRIME). The PRIME app provides users with a motivational coach to set personalized goals and secure social networking for peer support. OBJECTIVE: This study investigated whether deficits in cognition and motivation in people with a psychosis spectrum disorder (N=100) can be successfully addressed with 30 hours of TCT+PRIME as compared with 30 hours of a computer games control condition (CG) plus PRIME (CG+PRIME). Here, we describe our study procedures, the feasibility and acceptability of the intervention, and the results on all primary outcomes. METHODS: In this double-blind randomized controlled trial, English-speaking participants completed all cognitive training, PRIME activities, and assessments remotely. Participants completed a diagnostic interview and remote cognitive, clinical, and self-report measures at baseline, posttraining, and at a 6-month follow-up. RESULTS: This study included participants from 27 states across the United States and 8 countries worldwide. The study population was 58% (58/100) female, with a mean age of 33.77 (SD 10.70) years. On average, participants completed more than half of the cognitive training regimen (mean 18.58, SD 12.47 hours of training), and logged into the PRIME app 4.71 (SD 1.58) times per week. The attrition rate of 22% (22/100) was lower than that reported in our previous studies on remote cognitive training. The total sample showed significant gains in global cognition (P=.03) and attention (P<.001). The TCT+PRIME participants showed significantly greater gains in emotion recognition (P<.001) and global cognition at the trend level (P=.09), although this was not statistically significant, relative to the CG+PRIME participants. The total sample also showed significant improvements on multiple indices of motivation (P=.02-0.05), in depression (P=.04), in positive symptoms (P=.04), and in negative symptoms at a trend level (P=.09), although this was not statistically significant. Satisfaction with the PRIME app was rated at 7.74 (SD 2.05) on a scale of 1 to 10, with higher values indicating more satisfaction. CONCLUSIONS: These results demonstrate the feasibility and acceptability of remote cognitive training combined with the PRIME app and that this intervention can improve cognition, motivation, and symptoms in individuals with psychosis. TCT+PRIME appeared more effective in improving emotion recognition and global cognition than CG+PRIME. Future analyses will test the relationship between hours of cognitive training completed; PRIME use; and changes in cognition, motivation, symptoms, and functioning. TRIAL REGISTRATION: ClinicalTrials.gov NCT02782442; https://clinicaltrials.gov/study/NCT02782442.


Assuntos
Aplicativos Móveis , Transtornos Psicóticos , Adulto , Feminino , Humanos , Cognição , Treino Cognitivo , Motivação , Transtornos Psicóticos/terapia , Masculino
5.
J Environ Manage ; 339: 117902, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37060695

RESUMO

Nutrient offsetting allows nutrient point source polluters to pay for diffuse source nutrient reductions, or improvements in nutrient load reductions from alternative point sources. These programs have the potential to provide a more cost-effective approach to achieve water quality goals in waterways compared to infrastructure upgrades. However, worldwide adoption of nutrient offset/trading has not been realized. Here, we identified the biophysical-chemical knowledge gaps that can act as barriers to adopting these programs and summarized areas where further research is needed. This includes a) evaluating if any appropriate spatial scale (local-, catchment-, or regional-scale) and time scale (especially for areas with dry/wet cycles) exists to achieve nutrient load management goals, and b) quantifying nutrient characteristic differences and load contributions between point and diffuse sources to determine possible offsets between the two. Where offsets are appropriate, there is also a need to 1) improve monitoring design and reduce modelling uncertainties to better quantify diffuse nutrient loads; 2) quantify and manage uncertainties in catchment interventions to reduce nutrient loads, and design effective long-term monitoring and maintenance to sustain intervention outcomes; 3) prioritize areas within catchments that are key nutrient sources for catchment interventions to achieve the optimal outcomes for nutrient load management and catchment and aquatic ecosystem health; and 4) develop methodologies to determine the environmental equivalency ratio between different nutrient sources in terms of ecosystem effects. This would include identifying the best metric to quantify equivalency ratios, determining discharge patterns for different nutrient sources, and linking this with ecosystem responses across seasons and in the downstream receiving environment. Addressing the identified knowledge gaps will improve the program feasibility assessment process as well as confidence and certainty in the environmental outcomes of nutrient offsetting.


Assuntos
Ecossistema , Monitoramento Ambiental , Monitoramento Ambiental/métodos , Qualidade da Água , Estações do Ano
6.
Stroke ; 53(2): 595-604, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34965737

RESUMO

BACKGROUND AND PURPOSE: High-risk atherosclerosis is an underlying cause of cardiovascular events, yet identifying the specific patient population at immediate risk is still challenging. Here, we used a rabbit model of atherosclerotic plaque rupture and human carotid endarterectomy specimens to describe the potential of molecular fibrin imaging as a tool to identify thrombotic plaques. METHODS: Atherosclerotic plaques in rabbits were induced using a high-cholesterol diet and aortic balloon injury (N=13). Pharmacological triggering was used in a group of rabbits (n=9) to induce plaque disruption. Animals were grouped into thrombotic and nonthrombotic plaque groups based on gross pathology (gold standard). All animals were injected with a novel fibrin-specific probe 68Ga-CM246 followed by positron emission tomography (PET)/magnetic resonance imaging 90 minutes later. 68Ga-CM246 was quantified on the PET images using tissue-to-background (back muscle) ratios and standardized uptake value. RESULTS: Both tissue-to-background (back muscle) ratios and standardized uptake value were significantly higher in the thrombotic versus nonthrombotic group (P<0.05). Ex vivo PET and autoradiography of the abdominal aorta correlated positively with in vivo PET measurements. Plaque disruption identified by 68Ga-CM246 PET agreed with gross pathology assessment (85%). In ex vivo surgical specimens obtained from patients undergoing elective carotid endarterectomy (N=12), 68Ga-CM246 showed significantly higher binding to carotid plaques compared to a D-cysteine nonbinding control probe. CONCLUSIONS: We demonstrated that molecular fibrin PET imaging using 68Ga-CM246 could be a useful tool to diagnose experimental and clinical atherothrombosis. Based on our initial results using human carotid plaque specimens, in vivo molecular imaging studies are warranted to test 68Ga-CM246 PET as a tool to stratify risk in atherosclerotic patients.


Assuntos
Fibrina , Trombose Intracraniana/diagnóstico por imagem , Placa Aterosclerótica/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos , Animais , Aorta Abdominal/diagnóstico por imagem , Músculos do Dorso/diagnóstico por imagem , Artérias Carótidas/diagnóstico por imagem , Feminino , Radioisótopos de Gálio , Humanos , Processamento de Imagem Assistida por Computador , Trombose Intracraniana/etiologia , Imageamento por Ressonância Magnética , Masculino , Placa Aterosclerótica/complicações , Coelhos
7.
J Am Chem Soc ; 141(14): 5916-5925, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30874437

RESUMO

We introduce a redox-active iron complex, Fe-PyC3A, as a biochemically responsive MRI contrast agent. Switching between Fe3+-PyC3A and Fe2+-PyC3A yields a full order of magnitude relaxivity change that is field-independent between 1.4 and 11.7 T. The oxidation of Fe2+-PyC3A to Fe3+-PyC3A by hydrogen peroxide is very rapid, and we capitalized on this behavior for the molecular imaging of acute inflammation, which is characterized by elevated levels of reactive oxygen species.  Injection of Fe2+-PyC3A generates strong, selective contrast enhancement of inflamed pancreatic tissue in a mouse model (caerulein/LPS model). No significant signal enhancement is observed in normal pancreatic tissue (saline-treated mice). Importantly, signal enhancement of the inflamed pancreas correlates strongly and significantly with ex vivo quantitation of the pro-inflammatory biomarker myeloperoxidase. This is the first example of using metal ion redox for the MR imaging of pathologic change in vivo. Redox-active Fe3+/2+ complexes represent a new design paradigm for biochemically responsive MRI contrast agents.


Assuntos
Complexos de Coordenação/química , Ferro/química , Imageamento por Ressonância Magnética/métodos , Animais , Meios de Contraste/química , Ligantes , Camundongos , Oxirredução , Pancreatite/diagnóstico por imagem , Água/química
8.
Dev Psychopathol ; 31(3): 1085-1099, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31156078

RESUMO

Though theory suggests that individual differences in neuroticism (a tendency to experience negative emotions) would be associated with altered functioning of the amygdala (which has been linked with emotionality and emotion dysregulation in childhood, adolescence, and adulthood), results of functional neuroimaging studies have been contradictory and inconclusive. We aimed to clarify the relationship between neuroticism and three hypothesized neural markers derived from functional magnetic resonance imaging during negative emotion face processing: amygdala activation, amygdala habituation, and amygdala-prefrontal connectivity, each of which plays an important role in the experience and regulation of emotions. We used general linear models to examine the relationship between trait neuroticism and the hypothesized neural markers in a large sample of over 500 young adults. Although neuroticism was not significantly associated with magnitude of amygdala activation or amygdala habituation, it was associated with amygdala-ventromedial prefrontal cortex connectivity, which has been implicated in emotion regulation. Results suggest that trait neuroticism may represent a failure in top-down control and regulation of emotional reactions, rather than overactive emotion generation processes, per se. These findings suggest that neuroticism, which has been associated with increased rates of transdiagnostic psychopathology, may represent a failure in the inhibitory neurocircuitry associated with emotion regulation.


Assuntos
Tonsila do Cerebelo/diagnóstico por imagem , Emoções/fisiologia , Neuroticismo/fisiologia , Personalidade/fisiologia , Córtex Pré-Frontal/diagnóstico por imagem , Adulto , Feminino , Humanos , Individualidade , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/diagnóstico por imagem , Gêmeos , Adulto Jovem
9.
Radiology ; 286(3): 865-872, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29117483

RESUMO

Purpose To compare intravascular contrast enhancement produced by the manganese-based magnetic resonance (MR) imaging contrast agent manganese-N-picolyl-N,N',N'-trans-1,2-cyclohexenediaminetriacetate (Mn-PyC3A) to gadopentetate dimeglumine (Gd-DTPA) and to evaluate the excretion, pharmacokinetics, and metabolism of Mn-PyC3A. Materials and Methods Contrast material-enhanced MR angiography was performed in baboons (Papio anubis; n = 4) by using Mn-PyC3A and Gd-DTPA. Dynamic imaging was performed for 60 minutes following Mn-PyC3A injection to monitor distribution and elimination. Serial blood sampling was performed to quantify manganese and gadolinium plasma clearance by using inductively coupled plasma mass spectrometry and to characterize Mn-PyC3A metabolism by using high-performance liquid chromatography. Intravascular contrast enhancement in the abdominal aorta and brachiocephalic artery was quantified by measuring contrast-to-noise ratios (CNRs) versus muscle at 9 seconds following Mn-PyC3A or Gd-DTPA injection. Plasma pharmacokinetics were modeled with a biexponential function, and data were compared with a paired t test. Results Aorta versus muscle CNR (mean ± standard deviation) with Mn-PyC3A and Gd-DTPA was 476 ± 77 and 538 ± 120, respectively (P = .11). Brachiocephalic artery versus muscle CNR was 524 ± 55 versus 518 ± 140, respectively (P = .95). Mn-PyC3A was eliminated via renal and hepatobiliary excretion with similar pharmacokinetics to Gd-DTPA (area under the curve between 0 and 30 minutes, 20.2 ± 3.1 and 17.0 ± 2.4, respectively; P = .23). High-performance liquid chromatography revealed no evidence of Mn-PyC3A biotransformation. Conclusion Mn-PyC3A enables contrast-enhanced MR angiography with comparable contrast enhancement to gadolinium-based agents and may overcome concerns regarding gadolinium-associated toxicity and retention. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Meios de Contraste/farmacocinética , Gadolínio DTPA/farmacocinética , Angiografia por Ressonância Magnética/métodos , Manganês/farmacocinética , Compostos Organometálicos/farmacocinética , Animais , Aorta Abdominal/diagnóstico por imagem , Feminino , Meia-Vida , Eliminação Hepatobiliar , Processamento de Imagem Assistida por Computador/métodos , Rim/diagnóstico por imagem , Rim/metabolismo , Papio , Artéria Renal/diagnóstico por imagem
10.
Radiology ; 287(2): 581-589, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29156148

RESUMO

Purpose To evaluate the biodistribution, metabolism, and pharmacokinetics of a new type I collagen-targeted magnetic resonance (MR) probe, CM-101, and to assess its ability to help quantify liver fibrosis in animal models. Materials and Methods Biodistribution, pharmacokinetics, and stability of CM-101 in rats were measured with mass spectrometry. Bile duct-ligated (BDL) and sham-treated rats were imaged 19 days after the procedure by using a 1.5-T clinical MR imaging unit. Mice were treated with carbon tetrachloride (CCl4) or with vehicle two times a week for 10 weeks and were imaged with a 7.0-T preclinical MR imaging unit at baseline and 1 week after the last CCl4 treatment. Animals were imaged before and after injection of 10 µmol/kg CM-101. Change in contrast-to-noise ratio (ΔCNR) between liver and muscle tissue after CM-101 injection was used to quantify liver fibrosis. Liver tissue was analyzed for Sirius Red staining and hydroxyproline content. The institutional subcommittee for research animal care approved all in vivo procedures. Results CM-101 demonstrated rapid blood clearance (half-life = 6.8 minutes ± 2.4) and predominately renal elimination in rats. Biodistribution showed low tissue gadolinium levels at 24 hours (<3.9% injected dose [ID]/g ± 0.6) and 10-fold lower levels at 14 days (<0.33% ID/g ± 12) after CM-101 injection with negligible accumulation in bone (0.07% ID/g ± 0.02 and 0.010% ID/g ± 0.004 at 1 and 14 days, respectively). ΔCNR was significantly (P < .001) higher in BDL rats (13.6 ± 3.2) than in sham-treated rats (5.7 ± 4.2) and in the CCl4-treated mice (18.3 ± 6.5) compared with baseline values (5.2 ± 1.0). Conclusion CM-101 demonstrated fast blood clearance and whole-body elimination, negligible accumulation of gadolinium in bone or tissue, and robust detection of fibrosis in rat BDL and mouse CCl4 models of liver fibrosis. © RSNA, 2017 Online supplemental material is available for this article.


Assuntos
Fibrose/patologia , Gadolínio/farmacocinética , Cirrose Hepática/diagnóstico por imagem , Fígado/patologia , Imageamento por Ressonância Magnética , Polissacarídeos Bacterianos/farmacocinética , Animais , Tetracloreto de Carbono/farmacocinética , Modelos Animais de Doenças , Fibrose/diagnóstico por imagem , Meia-Vida , Fígado/diagnóstico por imagem , Espectrometria de Massas , Camundongos , Ratos , Distribuição Tecidual
11.
Br J Psychiatry ; 210(3): 216-222, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28153927

RESUMO

BackgroundPatients with schizophrenia have shown cognitive improvements following cognitive remediation, but the neuroplastic changes that support these processes are not fully understood.AimsTo use a triple-blind, placebo-controlled trial to examine neural activation before and after cognitive remediation or a computer skills training (CST) placebo (trial registration: NCT00995553)).MethodTwenty-seven participants underwent functional magnetic resonance imaging before and after being randomised to either cognitive remediation intervention or CST. Participants completed two variants of the N-back task during scanning and were assessed on measures of cognition, functional capacity, community functioning and symptoms.ResultsWe observed a group × time interaction in the left prefrontal cortex, wherein the cognitive remediation group showed increased activation. These changes correlated with improved task accuracy within the cognitive remediation group, whereas there was no relationship between changes in activation in untrained cognitive measures. Significant changes were not observed in other hypothesised areas for the cognitive remediation group.ConclusionsWe replicated the finding that cognitive remediation increases left lateral prefrontal activation during a working memory task in patients with schizophrenia, suggesting this may be an important neural target for these types of interventions.


Assuntos
Córtex Cerebral/fisiopatologia , Disfunção Cognitiva/reabilitação , Remediação Cognitiva/métodos , Plasticidade Neuronal/fisiologia , Esquizofrenia/reabilitação , Adulto , Disfunção Cognitiva/etiologia , Método Duplo-Cego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esquizofrenia/complicações
12.
J Am Chem Soc ; 138(49): 15861-15864, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960350

RESUMO

We introduce a new biochemically responsive Mn-based MRI contrast agent that provides a 9-fold change in relaxivity via switching between the Mn3+ and Mn2+ oxidation states. Interchange between oxidation states is promoted by a "Janus" ligand that isomerizes between binding modes that favor Mn3+ or Mn2+. It is the only ligand that supports stable complexes of Mn3+ and Mn2+ in biological milieu. Rapid interconversion between oxidation states is mediated by peroxidase activity (oxidation) and l-cysteine (reduction). This Janus system provides a new paradigm for the design of biochemically responsive MRI contrast agents.


Assuntos
Quelantes/química , Meios de Contraste/química , Cisteína/química , Imageamento por Ressonância Magnética , Manganês/química , Peroxidase/química , Quelantes/metabolismo , Meios de Contraste/metabolismo , Cisteína/metabolismo , Humanos , Manganês/metabolismo , Estrutura Molecular , Oxirredução , Peroxidase/metabolismo
13.
Sci Total Environ ; 931: 172548, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38643882

RESUMO

The Brisbane River estuary is an anthropogenically-impacted waterway in southeast Queensland, Australia. The estuary is over 80 km long and flows through an urbanised region. It receives over 500 t per year of total nitrogen (N) from direct point-source discharges in addition to sporadic flood loads of N from an agriculturally impacted upper catchment. Comprehensive water quality monitoring data for the estuary have been collected from at least 2001. This monitoring data includes ambient nutrient concentrations in the estuary, nutrient concentration and volume of the catchment inflows, and nutrient concentration and volume of point source discharges. This long-term data from a range of sources was used to determine temporal and spatial variations in concentrations, forms, stores and loads of N along the estuary for the period 2001 to 2022. Results showed that, during low-flow periods, the store of N in the mid-upper estuary (33-81 km upstream) is significantly determined by point-source discharges to this reach, and therefore the store of N can be modelled. Model parameters are the daily point source loads, a point source load decay factor, and a background constant store. In the lower estuary (0-33 km upstream) N store can be accurately determined based on dilution with seawater, with point sources not having significant influence on total N in the reach. Total N from large flood events was found to largely pass through the estuary without detectable removal processes, delivering catchment derived N directly to coastal waters. This work informs potential application of nutrient offsets in the estuary, guiding where and when offset options will be effective to mitigate the water quality impacts of point-source nutrients.

14.
Artigo em Inglês | MEDLINE | ID: mdl-36775194

RESUMO

BACKGROUND: Neural oscillations support perception, attention, and higher-order decision making. Aberrations in the strength or consistency of these oscillations in response to stimuli may underlie impaired visual perception and attention in schizophrenia. Here, we examined the phase and power of alpha oscillations (8-12 Hz) as well as aspects of beta and theta frequency oscillations during a demanding visual sustained attention task. METHODS: Patients with schizophrenia (n = 74) and healthy control participants (n = 68) completed the degraded stimulus continuous performance task during electroencephalography. We used time-frequency analysis to evaluate the consistency (intertrial phase coherence) of the alpha cycle shortly after stimulus presentation (50-250 ms). For oscillation strength, we examined event-related desynchronization in a later window associated with decision making (360-700 ms). RESULTS: Alpha intertrial phase coherence was reduced in schizophrenia, and similar reductions were observed in theta (4-7 Hz) and beta (13-20 Hz), suggesting a lack of responsiveness in slower oscillations to visual stimuli. Alpha and beta event-related desynchronization were also reduced in schizophrenia and associated with worse task performance, increased symptoms, and poorer cognition, suggesting that limited responsiveness of oscillations is related to impairments in the disorder. Individuals with lower intertrial phase coherence had slower resting-state alpha rhythms consistent with dysfunctional oscillations persisting across default and task-related brain states. CONCLUSIONS: In schizophrenia, abnormalities in the phase consistency and strength of slower oscillations during visual perception are related to symptoms and cognitive functioning. Altered visual perception and impaired attention in the disorder may be the consequence of aberrant slower oscillations that fail to dynamically reset and modulate in response to stimuli.


Assuntos
Esquizofrenia , Humanos , Eletroencefalografia , Encéfalo , Percepção Visual/fisiologia , Ritmo alfa/fisiologia
15.
J Neurointerv Surg ; 16(3): 318-322, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-37586818

RESUMO

BACKGROUND: There has been a recent decrease in interventional management of cerebral arteriovenous malformations (AVMs). The objective of our study was to evaluate the changing patterns in management of AVMs in the first year of the COVID-19 pandemic. METHODS: The National Inpatient Sample (NIS) database was used. From 2016 to 2020, patients with an International Classification of Diseases, 10th revision (ICD-10) diagnosis code for a cerebral AVM were included. An intervention was defined as ICD-10 code for surgical, endovascular, or stereotactic radiosurgery treatment. Odds ratios (ORs) were calculated using a logistic regression model with covariates deemed to be clinically relevant. RESULTS: 63 610 patients with AVMs were identified between 2016 and 2020, 14 340 of which were ruptured. In 2020, patients had an OR of 0.69 for intervention of an unruptured AVM (P<0.0001) compared with 2016-19. The rate of intervention for unruptured AVMs decreased to 13.5% in 2020 from 17.6% in 2016-19 (P<0.0001). The rate of AVM rupture in 2020 increased to 23.9% from 22.2% in 2016-19 (P<0.0001). In 2020, patients with ruptured AVMs had an OR for inpatient mortality of 1.72 compared with 2016-19. Linear regression analysis from 2016 to 2020 showed an inverse relationship between intervention rate and rupture rate (slope -0.499, R2=0.88, P=0.019). CONCLUSION: In 2020, the rate of intervention for unruptured cerebral AVMs decreased compared with past years, with an associated increase in the rate of rupture. Patients with ruptured AVMs also had a higher odds of mortality.


Assuntos
COVID-19 , Malformações Arteriovenosas Intracranianas , Radiocirurgia , Humanos , Resultado do Tratamento , Pandemias , Malformações Arteriovenosas Intracranianas/epidemiologia , Malformações Arteriovenosas Intracranianas/terapia , Malformações Arteriovenosas Intracranianas/complicações , Ruptura/cirurgia , Estudos Retrospectivos
16.
J Neurointerv Surg ; 16(4): 342-346, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-37263776

RESUMO

BACKGROUND: Preliminary studies show that patients with large vessel occlusion (LVO) acute ischemic strokes have worse outcomes with concurrent COVID-19 infection. We investigated the outcomes for patients with LVO strokes undergoing mechanical thrombectomy (MT) with concurrent COVID-19 infection. METHODS: The National Inpatient Database (NIS) was used for our analysis. Patients in the year 2020 with an ICD-10 diagnosis code for acute ischemic stroke and procedural code for MT were included with and without COVID-19. Odds ratios (OR) were calculated using a logistic regression model with age, sex, stroke location, Elixhauser comorbidity score, and other patient variables deemed clinically relevant as covariates. RESULTS: Patients in the COVID-19 group were younger (64.3±14.4 vs 69.4±14.5 years, P<0.001), had a higher rate of inpatient mortality (22.4% vs 10.1%, P<0.001), and a longer length of stay (10 vs 6 days, P<0.001). Patients with COVID-19 had higher odds of death (OR 2.78, 95% CI 2.11 to 3.65) and lower odds of a routine discharge (OR 0.65, 95% CI 0.48 to 0.89). There was no difference in the odds of subsequent stroke and cerebral hemorrhage, but patients with COVID-19 had statistically significantly higher odds of respiratory failure, pulmonary embolism, deep vein thrombosis, myocardial infarction, acute kidney injury, and sepsis. CONCLUSIONS: Patients with LVOs undergoing MT within the 2020 NIS database had worse outcomes when co-diagnosed with COVID-19, likely due to non-neurological manifestations of COVID-19.


Assuntos
Arteriopatias Oclusivas , Isquemia Encefálica , COVID-19 , AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Estudos Retrospectivos , AVC Isquêmico/cirurgia , AVC Isquêmico/etiologia , Trombectomia/efeitos adversos , Resultado do Tratamento , Acidente Vascular Cerebral/etiologia , Arteriopatias Oclusivas/etiologia , Isquemia Encefálica/terapia , Isquemia Encefálica/etiologia
17.
World Neurosurg ; 186: 174-183.e1, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38484970

RESUMO

BACKGROUND: Craniopharyngiomas are benign tumors of the anterior skull base arising from epithelial remnants of Rathke pouch. They mainly occur in the suprasellar space, can be incredibly debilitating, and remain difficult to resect as they frequently involve critical neurovascular structures. Although it is embryologically possible for craniopharyngiomas to arise extracranially along the entire migrational path of Rathke pouch, these remain exceedingly rare, especially among adults, and can be mistaken for nasopharyngeal cancer. As such, minimal data exist evaluating the management and outcomes of such lesions. We evaluated our institutional experience with purely infrasellar nasopharyngeal craniopharyngiomas and obtained individual patient data reported in the contemporary literature to better characterize the demographics, presentation, surgical management, and long-term outcomes of these lesions. METHODS: A systematic review of the literature was performed to identify previously published cases of purely infrasellar nasopharyngeal craniopharyngioma in 3 electronic databases: MEDLINE (PubMed), Embase, and Scopus. Search terms were "infrasellar craniopharyngioma" and "nasopharyngeal craniopharyngioma." RESULTS: We identified 25 cases, in which 72% of patients presented with symptoms of nasal obstruction, epistaxis, or headache. An endoscopic approach was performed in 40% of cases; 83.3% of all patients had gross total resection, with 60% having no recurrence at a median follow-up of 13 months. No postoperative complications were reported. Tumor location involving the cavernous sinus was associated with incomplete resection (100%) compared with tumors not involving the cavernous sinus (87%) (P = 0.033). CONCLUSIONS: While uncommon, infrasellar nasopharyngeal craniopharyngiomas appear to have better perioperative and long-term surgical outcomes than their suprasellar counterparts.


Assuntos
Craniofaringioma , Neoplasias Nasofaríngeas , Neoplasias Hipofisárias , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Craniofaringioma/cirurgia , Craniofaringioma/diagnóstico por imagem , Neoplasias Nasofaríngeas/cirurgia , Neoplasias Nasofaríngeas/diagnóstico por imagem , Procedimentos Neurocirúrgicos/métodos , Neoplasias Hipofisárias/cirurgia , Neoplasias Hipofisárias/diagnóstico por imagem
18.
AME Case Rep ; 8: 17, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38234343

RESUMO

Background: Distal cervical internal carotid artery (cICA) pseudoaneurysms are uncommon. They may lead to thromboembolic or hemorrhagic complications, especially in young adults. We report one of the first cases in the literature regarding the management via PK Papyrus (Biotronik, Lake Oswego, Oregon, USA) balloon-mounted covered stent of a 23-year-old male with an enlarging cervical carotid artery pseudoaneurysm and progressive internal carotid artery stenosis. Case Description: We report the management of a 23-year-old male with an enlarging cervical carotid artery pseudoaneurysm and progressive internal carotid artery stenosis. Based on clinical judgment and imaging analysis, the best option to seal the aneurysm was a PK Papyrus 5×26 balloon-mounted covered stent. A follow-up angiogram showed no residual filling of the pseudoaneurysm, but there was some contrast stagnation just proximal to the stent, which is consistent with a residual dissection flap. We then deployed another PK Papyrus 5×26 balloon-mounted covered stent, providing some overlap at the proximal end of the stent. An angiogram following this subsequent deployment demonstrated complete reconstruction of the cICA with no residual evidence of pseudoaneurysm or dissection flap. There were no residual in-stent stenosis or vessel stenosis. The patient was discharged the day after the procedure with no complications. Conclusions: These positive outcomes support the use of a balloon-mounted covered stent as a safe and feasible modality with high technical success for endovascular management of pseudoaneurysm.

19.
World Neurosurg ; 185: e442-e450, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38364894

RESUMO

BACKGROUND: Giant falcine meningiomas are surgically complex as they are deep in location, concealed by normal brain parenchyma, in close proximity to various neurovascular structures, and frequently involve the falx bilaterally. Although classically accessed using a bifrontal craniotomy and interhemispheric approach, little data exist on alternative operative corridors for these challenging tumors. We evaluated perioperative and long-term outcomes in patients undergoing transcortical resection of giant bilateral falcine meningiomas. METHODS: From 2013 to 2022, fourteen patients with giant bilateral falcine meningiomas treated via a transcortical approach at our institution were identified. Perioperative and long-term outcomes were evaluated to determine predictors of adverse events. Corticectomy depth was also analyzed to determine if it correlated with increased postoperative seizure rates. RESULTS: 57.1% of cases were WHO grade 2 meningiomas. Average tumor volume was 77.8 ± 46.5 cm3 and near/gross total resection was achieved in 78.6% of patients. No patient developed a venous infarct or had seizures in the 6 months after surgery. Average corticectomy depth was 0.83 ± 0.71 cm and increasing corticectomy depth did not correlate with higher risk of postoperative seizures (P = 0.44). Increasing extent of tumor resection correlated with lower tumor grade (P = 0.011) and only 1 patient required repeat resection during a median follow-period of 24.9 months. CONCLUSIONS: The transcortical approach is a safe alternative corridor for accessing giant, falcine meningiomas, and postoperative seizures were not found to correlate with increasing corticectomy depth. Further prospective studies are necessary to determine the best approach to these surgically complex lesions.


Assuntos
Neoplasias Meníngeas , Meningioma , Procedimentos Neurocirúrgicos , Humanos , Meningioma/cirurgia , Feminino , Masculino , Neoplasias Meníngeas/cirurgia , Neoplasias Meníngeas/patologia , Pessoa de Meia-Idade , Idoso , Adulto , Procedimentos Neurocirúrgicos/métodos , Resultado do Tratamento , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Craniotomia/métodos , Estudos Retrospectivos , Córtex Cerebral/cirurgia , Carga Tumoral
20.
World Neurosurg ; 186: e440-e448, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38583567

RESUMO

OBJECTIVE: As the coronavirus disease 2019 (COVID-19) pandemic spread to the United States in 2020, there was an impetus toward postponing or ceasing nonurgent transsphenoidal pituitary surgeries to prevent the spread of the virus. Some centers encouraged transcranial approaches for patients with declining neurologic function. However, no large-scale data exist evaluating the effects that this situation had on national pituitary practice patterns. METHODS: Pituitary surgeries in the National Inpatient Sample were identified from 2017 to 2020. Surgeries in 2020 were compared with the 3 years previously to determine any differences in demographics, surgical trends/approaches, and perioperative outcomes. RESULTS: In 2020, there was a decline in overall pituitary surgeries (34.2 vs. 36.3%; odds ratio (OR), 0.88; P < 0.001) yet transsphenoidal approaches represented a higher proportion of interventions (69.0 vs. 64.9%; P < 0.001). Neurosurgical complications were higher (51.9 vs. 47.4%; OR, 1.13; P < 0.001) and patients were less likely to be discharged home (86.4 vs. 88.5%; OR, 0.84; P < 0.001). This finding was especially true in April 2020 during the first peak in COVID-19 cases, when transcranial approaches and odds of mortality/complications were highest. CONCLUSIONS: In 2020, transsphenoidal surgery remained the preferred approach for pituitary tumor resection despite initial recommendations against the approach to prevent COVID-19 spread. Pituitary surgeries had a higher risk of periprocedural complications despite accounting for preoperative comorbidities, COVID-19 infection status, and surgical approach, suggesting that an overwhelmed hospital system can negatively influence surgical outcomes in noninfected patients.


Assuntos
COVID-19 , Procedimentos Neurocirúrgicos , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Masculino , Feminino , Procedimentos Neurocirúrgicos/métodos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia , Adulto , Idoso , Neoplasias Hipofisárias/cirurgia , Pandemias , Doenças da Hipófise/cirurgia , Complicações Pós-Operatórias/epidemiologia , Hipófise/cirurgia
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