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1.
PLoS One ; 19(4): e0301622, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38630695

RESUMO

This paper proposes a reinforced concrete (RC) boundary beam-wall system that requires less construction material and a smaller floor height compared to the conventional RC transfer girder system. The structural performance of this system subjected to axial compression was evaluated by performing a structural test on four specimens of 1/2 scale. In addition, three-dimensional nonlinear finite element analysis was also performed to verify the effectiveness of the boundary beam-wall system. Three test parameters such as the lower wall length-to-upper wall length ratio, lower wall thickness, and stirrup details of the lower wall were considered. The load-displacement curve was plotted for each specimen and its failure mode was identified. The test results showed that decrease in the lower wall length-to-upper wall length ratio significantly reduced the peak strength of the boundary beam-wall system and difference in upper and lower wall thicknesses resulted in lateral bending caused by eccentricity in the out-of-plane direction. Additionally, incorporating cross-ties and reducing stirrup spacing in the lower wall significantly improved initial stiffness and peak strength, effectively minimizing stress concentration.


Assuntos
Materiais de Construção , Compressão de Dados , Análise de Elementos Finitos , Fenômenos Físicos
2.
PLoS One ; 19(3): e0297154, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38446783

RESUMO

This study introduces a novel concrete-filled tube (CFT) column system featuring a steel tube comprised of four internal triangular units. The incorporation of these internal triangular units serves to reduce the width-thickness ratio of the steel tube and augment the effective confinement area of the infilled concrete. This design enhancement is anticipated to result in improved structural strength and ductility, contributing to enhanced overall performance and sustainability. To assess the effectiveness of the newly proposed column system, a full-scale test was conducted on five square steel tube column specimens subjected to axial compression. Among these specimens, two adhered to the conventional steel tube column design, while the remaining three featured the new CFT columns with internal triangular units. The shape of the CFT column, the presence of infilled concrete and the presence of openings on the ITUs were considered as test parameters. The test results reveal that the ductility of the newly proposed CFT column system exhibited a minimum 30% improvement compared to the conventional CFT column. In addition, the initial stiffness and axial compressive strength of the new system were found to be comparable to those of the conventional CFT column.


Assuntos
Compressão de Dados , Força Compressiva , Fenômenos Físicos , Aço , Resistência à Tração
3.
Mar Environ Res ; 196: 106376, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38316569

RESUMO

The northeastern East China Sea is a highly dynamic marine ecosystem influenced by seasonally varying water mass properties. However, despite being among the world's fastest-warming ocean, there has been limited investigation into the impacts of warming on protistan communities. We collected seawater from two stations (E42 and E46) with different natural protist communities and environmental attributes to investigate the acclimation of the two communities to artificially elevated temperatures (ambient T, +2, and +4 °C). Nutrient and Chl-a conditions reflected oceanographic differences, providing insights into protistan community dynamics. Notably, small-sized autotrophic protists prevailed in the phosphate-deficient E42 community, with mid-incubation heterotrophic conversions. Higher temperatures exacerbated the effects of the P deficiency on the E42 community. While the proportions of Bacillariophyta increased only in the nutrient-balanced E46 communities, those of mixotrophic dinoflagellates increased with elevated temperature, regardless of P deficiency, suggesting that mixotrophy likely aids adaptation in changing marine environments. In summary, the findings of this microcosm study illuminate the potential modulation of spring protistan communities in the northeastern East China Sea under anticipated future warming.


Assuntos
Diatomáceas , Dinoflagellida , Ecossistema , Água do Mar , Diatomáceas/fisiologia , China , Fitoplâncton/fisiologia
4.
J Korean Med Sci ; 39(3): e32, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38258364

RESUMO

BACKGROUND: Understanding adolescents' mental health during the coronavirus disease 2019 (COVID-19) pandemic and identifying those most at risk is an urgent public health challenge. This study explored the trend of suicide attempts and the association between loneliness, family financial stress, and suicide attempts during the COVID-19 pandemic among adolescents. METHODS: Data of the 2020 to 2022 Korea Youth Risk Behavior Surveys for adolescents aged 13-18 years were used. Multivariate logistic regression analyses were performed to examine the association between suicide attempts, family financial stress, and loneliness during the COVID-19 pandemic. RESULTS: The trend of suicide attempt rates was lowest in 2020 (1.9%, 1,034 out of 53,534) and it showed an increasing trend with rates of 2.2% (1,159 out of 53,445) in 2021 and 2.5% (1,271 out of 50,455) in 2022. The risk of suicide attempt was higher among adolescents who experienced financial stress (in 2020: adjusted odds ratio [AOR], 1.53, 95% confidence interval [CI], 1.26-1.88; in 2021: AOR, 1.63, 95% CI, 1.03-1.54) and felt lonely (in 2020: AOR, 2.19, 95% CI, 1.78-2.70; in 2021: AOR, 2.65, 95% CI, 2.16-3.26; in 2022: AOR, 1.3, 95% CI, 1.04-1.55) than those who did not. CONCLUSION: The COVID-19 pandemic affected the suicide attempts of adolescents, with financial stress and feelings of loneliness closely linked to this impact. Although the pandemic nears its end, the persistent risk of suicide attempts among adolescents remains a concern. Therefore, it is imperative to implement targeted screening and interventions to address adolescent suicide risk.


Assuntos
COVID-19 , Pandemias , Adolescente , Humanos , Tentativa de Suicídio , COVID-19/epidemiologia , Fatores de Risco , Emoções
5.
Surg Endosc ; 37(8): 5865-5874, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37069430

RESUMO

BACKGROUND AND AIMS: Perforation is a life-threatening adverse event of colonoscopy that often requires hospitalization and surgery. We aimed to prospectively assess the incidence of colonoscopy-related perforation in a multicenter registry and to analyze the clinical factors associated with poor clinical outcomes. METHODS: This prospective observational study was conducted at six tertiary referral hospitals between 2017 and 2020, and included patients with colonic perforation after colonoscopy. Poor clinical outcomes were defined as mortality, surgery, and prolonged hospitalization (> 13 days). Logistic regression was used to identify factors associated with poor clinical outcomes. RESULTS: Among 84,673 patients undergoing colonoscopy, 56 had colon perforation (0.66/1000, 95% confidence interval [CI] 0.51-0.86). Perforation occurred in 12 of 63,602 diagnostic colonoscopies (0.19/1000, 95% CI 0.11-0.33) and 44 of 21,071 therapeutic colonoscopies (2.09/1000, 95% CI 1.55-2.81). Of these, 15 (26.8%) patients underwent surgery, and 25 (44.6%) patients had a prolonged hospital stay. One patient (1.8%) died after perforation from a diagnostic colonoscopy. In the multivariate analysis, diagnostic colonoscopy (adjusted odds ratio [aOR] 196.43, p = 0.025) and abdominal rebound tenderness (aOR 17.82, p = 0.012) were independent risk factors for surgical treatment. The location of the sigmoid colon (aOR 18.57, p = 0.048), delayed recognition (aOR 187.71, p = 0.008), and abdominal tenderness (aOR 63.20, p = 0.017) were independent risk factors for prolonged hospitalization. CONCLUSIONS: This prospective study demonstrated that the incidence of colonoscopy-related perforation was 0.66/1000. The incidence rate was higher in therapeutic colonoscopy, whereas the risk for undergoing surgery was higher in patients undergoing diagnostic colonoscopy. Colonoscopy indication (diagnostic vs. therapeutic), physical signs, the location of the sigmoid perforation, and delayed recognition were independent risk factors for poor clinical outcomes in colonoscopy-related perforation.


Assuntos
Doenças do Colo , Perfuração Intestinal , Humanos , Estudos Prospectivos , Incidência , Colonoscopia/efeitos adversos , Fatores de Risco , Doenças do Colo/epidemiologia , Doenças do Colo/etiologia , Doenças do Colo/cirurgia , Sistema de Registros , Perfuração Intestinal/epidemiologia , Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Estudos Retrospectivos
6.
Schizophr Bull ; 49(3): 726-737, 2023 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-36869757

RESUMO

BACKGROUND AND HYPOTHESIS: Risk-taking in specific contexts can be beneficial, leading to rewarding outcomes. Schizophrenia is associated with disadvantageous decision-making, as subjects pursue uncertain risky rewards less than controls. However, it is unclear whether this behavior is associated with more risk sensitivity or less reward incentivization. Matching on demographics and intelligence quotient (IQ), we determined whether risk-taking was more associated with brain activation in regions affiliated with risk evaluation or reward processing. STUDY DESIGN: Subjects (30 schizophrenia/schizoaffective disorder, 30 controls) completed a modified, fMRI Balloon Analogue Risk Task. Brain activation was modeled during decisions to pursue risky rewards and parametrically modeled according to risk level. STUDY RESULTS: The schizophrenia group exhibited less risky-reward pursuit despite previous adverse outcomes (Average Explosions; F(1,59) = 4.06, P = .048) but the comparable point at which risk-taking was volitionally discontinued (Adjusted Pumps; F(1,59) = 2.65, P = .11). Less activation was found in schizophrenia via whole brain and region of interest (ROI) analyses in the right (F(1,59) = 14.91, P < 0.001) and left (F(1,59) = 16.34, P < 0.001) nucleus accumbens (NAcc) during decisions to pursue rewards relative to riskiness. Risk-taking correlated with IQ in schizophrenia, but not controls. Path analyses of average ROI activation revealed less statistically determined influence of anterior insula upon dorsal anterior cingulate bilaterally (left: χ2 = 12.73, P < .001; right: χ2 = 9.54, P = .002) during risky reward pursuit in schizophrenia. CONCLUSIONS: NAcc activation in schizophrenia varied less according to the relative riskiness of uncertain rewards compared to controls, suggesting aberrations in reward processing. The lack of activation differences in other regions suggests similar risk evaluation. Less insular influence on the anterior cingulate may relate to attenuated salience attribution or inability for risk-related brain region collaboration to sufficiently perceive situational risk.


Assuntos
Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Encéfalo , Giro do Cíngulo/diagnóstico por imagem , Núcleo Accumbens/diagnóstico por imagem , Recompensa , Tomada de Decisões/fisiologia , Imageamento por Ressonância Magnética
7.
Neuroimage Clin ; 36: 103237, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36451348

RESUMO

Cerebellar-cortical resting-state functional connectivity (rsFC) has been reported to be altered in cannabis users. However, this association may be due to genetic and environmental confounding rather than a causal relationship between cannabis use and changes in rsFC. In this co-twin control study, linear mixed models were used to assess relationships between the number of lifetime cannabis uses (NLCU) and age of cannabis onset (ACO) with cerebellar-cortical rsFC. The rsFC with seven functional networks was evaluated in 147 monozygotic and 82 dizygotic twin pairs. Importantly, the use of genetically informed models in this twin sample facilitated examining whether shared genetic or environmental effects underlie crude associations between cannabis measures and connectivity. Individual-level phenotypic analyses (i.e., accounting for twin-pair non-independence) showed that individuals in the full sample with earlier ACO and higher NLCU had lower cerebellar rsFC within the VA, DA, and FP networks. Yet, there were no significant differences in cerebellar-cortical rsFC between monozygotic twins who were discordant for cannabis measures. These findings suggest shared genetic or environmental confounds contribute to associations between cannabis use and altered cerebellar-cortical rsFC, rather than unique causal impacts of cannabis use on cerebellar-cortical rsFC.


Assuntos
Cannabis , Humanos , Gêmeos Dizigóticos/genética , Gêmeos Monozigóticos/genética , Idade de Início , Cerebelo/diagnóstico por imagem
8.
Neuroimage ; 264: 119748, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36370957

RESUMO

Although conscious perception is a fundamental cognitive function, its neural correlates remain unclear. It remains debatable whether thalamocortical interactions play a decisive role in conscious perception. To clarify this, we used functional magnetic resonance imaging (fMRI) where flickering red and green visual cues could be perceived either as a non-fused colour or fused colour. Here we show significantly differentiated fMRI neurodynamics only in higher-order thalamocortical regions, compared with first-order thalamocortical regions. Anticorrelated neurodynamic behaviours were observed between the visual stream network and default-mode network. Its dynamic causal modelling consistently provided compelling evidence for the involvement of higher-order thalamocortical iterative integration during conscious perception of fused colour, while inhibitory control was revealed during the non-fusion condition. Taken together with our recent magnetoencephalography study, our fMRI findings corroborate a thalamocortical inhibitory model for consciousness, where both thalamic inhibitory regulation and integrative signal iterations across higher-order thalamocortical regions are essential for conscious perception.


Assuntos
Estado de Consciência , Tálamo , Humanos , Estado de Consciência/fisiologia , Tálamo/fisiologia , Imageamento por Ressonância Magnética , Percepção
9.
Artigo em Inglês | MEDLINE | ID: mdl-35978711

RESUMO

Autism spectrum disorder (ASD) is a heterogeneous neurodevelopmental condition characterized by early-onset repetitive behaviors, restricted interests, sensory and motor difficulties, and impaired social interactions. Converging evidence from neuroimaging, lesion and postmortem studies, and rodent models suggests cerebellar involvement in ASD and points to promising targets for therapeutic interventions for the disorder. This review elucidates understanding of cerebellar mechanisms in ASD by integrating and contextualizing recent structural and functional cerebellar research.

10.
Schizophr Bull Open ; 2(1): sgab040, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34541537

RESUMO

The cognitive dysmetria theory of psychotic disorders posits that cerebellar circuit abnormalities give rise to difficulties coordinating motor and cognitive functions. However, brain activation during cerebellar-mediated tasks is understudied in schizophrenia. Accordingly, this study examined whether individuals with schizophrenia have diminished neural activation compared to controls in key regions of the delay eyeblink conditioning (dEBC) cerebellar circuit (eg, lobule VI) and cerebellar regions associated with cognition (eg, Crus I). Participants with schizophrenia-spectrum disorders (n = 31) and healthy controls (n = 43) underwent dEBC during functional magnetic resonance imaging (fMRI). Images were normalized using the Spatially Unbiased Infratentorial Template (SUIT) of the cerebellum and brainstem. Activation contrasts of interest were "early" and "late" stages of paired tone and air puff trials minus unpaired trials. Preliminary whole brain analyses were conducted, followed by cerebellar-specific SUIT and region of interest (ROI) analyses of lobule VI and Crus I. Correlation analyses were conducted between cerebellar activation, neuropsychological test scores, and psychotic symptom scores. In controls, the largest clusters of cerebellar activation peaked in lobule VI during early dEBC and Crus I during late dEBC. The schizophrenia group showed robust cortical activation to unpaired trials but no significant conditioning-related cerebellar activation. Crus I ROI activation during late dEBC was greater in the control than schizophrenia group. Greater Crus I activation correlated with higher working memory scores in the full sample and lower positive psychotic symptom severity in schizophrenia. Findings indicate functional cerebellar abnormalities in schizophrenia which relate to psychotic symptoms, lending direct support to the cognitive dysmetria framework.

11.
J Psychopharmacol ; 35(7): 823-832, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34034553

RESUMO

BACKGROUND: Cannabis use has been associated with abnormalities in cerebellar mediated motor and non-motor (i.e. cognition and personality) phenomena. Since the cerebellum is a region with high cannabinoid type 1 receptor density, these impairments may reflect alterations of signaling between the cerebellum and other brain regions. AIMS: We hypothesized that cerebellar-cortical resting-state functional connectivity (rsFC) would be altered in cannabis users, relative to their non-using peers. It was also hypothesized that differences in rsFC would be associated with cannabis use features, such as age of initiation and lifetime use. METHODS: Cerebellar-cortical and subcortical rsFCs were computed between 28 cerebellar lobules, defined by a spatially unbiased atlas template of the cerebellum, and individual voxels in the cerebral regions, in 41 regular cannabis users (20 female) and healthy non-using peers (N = 31; 18 female). We also investigated associations between rsFC and cannabis use features (e.g. lifetime cannabis use and age of initiation). RESULTS: Cannabis users demonstrated hyperconnectivity between the anterior cerebellar regions (i.e. lobule I-IV) with the posterior cingulate cortex, and hypoconnectivity between the rest of the cerebellum (i.e. Crus I and II, lobule VIIb, VIIIa, VIIIb, IX, and X) and the cortex. No associations were observed between features of cannabis use and rsFC. CONCLUSIONS: Cannabis use was associated with altered patterns of rsFC from the cerebellum to the cerebral cortex which may have a downstream impact on behavior and cognition.


Assuntos
Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Conectoma , Uso da Maconha , Adolescente , Adulto , Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
12.
Clin Endosc ; 54(3): 432-435, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33715342

RESUMO

Angiolipoma is a benign fatty neoplasm that has components of proliferating blood vessels. These types of lesions commonly occur in the subcutaneous tissue of the limbs and trunk. Angiolipoma in the gastrointestinal tract is extremely rare, and the final diagnosis generally depends on histological examination of the excised biopsy. In most previously reported cases, the lesions were diagnosed and treated with surgical management. In this study, we report a case of gastric angiolipoma of approximately 4 cm in size that was diagnosed and treated with endoscopic submucosal dissection.

13.
Surg Endosc ; 35(8): 4124-4133, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-32789723

RESUMO

BACKGROUND: Stent migration is one of the main drawbacks of covered self-expandable metal stent (SEMSs), occurring in up to 40% of malignant colorectal obstruction management cases. Various types of covered SEMSs have been developed to reduce this risk. We aimed to compare the effectiveness and complication rates of the flare-type covered SEMS (Flare) with those of the double-layered covered SEMS (ComVi). METHODS: We performed a prospective, randomized study in four tertiary referral centers between July 2016 and April 2018. Patients with malignant colorectal obstruction were eligible for the study. The primary outcome was migration rate as observed within the first month. Rates of technical success, clinical success, and complications within the first month were also assessed. RESULTS: A total of 60 patients were included (mean age, 70.5 ± 12.5 years; male, 31 [51.7%]). Flare and ComVi stents were applied in 30 patients each. The Flare and ComVi groups showed comparable technical success rates (90% [27/30] vs. 96.7% [29/30], p = 0.605) and clinical success rates (85.2% [23/27] vs. 75.9% [22/29], p = 0.589). Migration occurred in three (11.1%) and four (13.8%) cases in the Flare and ComVi groups, respectively, without significant difference (p = 0.99), and the risk of other complications, including perforation and re-obstruction, did not differ between the two groups. CONCLUSIONS: Our study indicates that both flare-shape and double-layered covered SEMSs are equally effective options for the management of malignant colorectal obstruction with low migration rates when compared with previously reported migration risk of covered SEMS.


Assuntos
Neoplasias Colorretais , Stents Metálicos Autoexpansíveis , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Cuidados Paliativos , Estudos Prospectivos , Stents Metálicos Autoexpansíveis/efeitos adversos , Stents , Resultado do Tratamento
14.
Sleep Med ; 76: 26-32, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33069999

RESUMO

OBJECTIVES: Short sleep duration has been known to be related to metabolic syndrome (MetS) . The aim of this study was to investigate the beneficial effects of weekend catch-up sleep (WCUS) on MetS in the Korean middle-aged population. METHODS: For this cross-sectional study, 1,812 participants aged 35-60 years were selected from the 2016-2018 Korean National Health and Nutrition Examination Survey (mean age 46.94 years, 49% male). Short sleep duration was defined as <6hrs on weekdays, and participants were divided into two groups: WCUS group and no weekend catch-up sleep group. Multiple logistic regression was performed to determine the association between WCUS and MetS prevalence. The covariates included age, sex, education, income, occupation, smoking, alcohol consumption, and physical activity. RESULTS: WCUS was significantly associated with lower MetS prevalence in the unadjusted model and in the model adjusted for socioeconomic and health behavior factors. CONCLUSION: These results support the beneficial effects of WCUS on lowering the risk of MetS among middle-aged chronic short sleepers.


Assuntos
Síndrome Metabólica , Sono , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Inquéritos Nutricionais , Prevalência , República da Coreia/epidemiologia , Fatores de Tempo
15.
Psychiatry Res Neuroimaging ; 304: 111133, 2020 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-32805441

RESUMO

There is accruing evidence of cerebellar abnormalities in individuals with schizophrenia as measured by performance on a variety of tasks believed to be dependent on cerebellar integrity, including delay eyeblink conditioning. There is also evidence of cerebellar dysfunction on a neural level in schizophrenia from both task-based and resting state neuroimaging studies, however few studies have examined cerebellar neural function while the cerebellum is directly recruited in individuals with schizophrenia. In the current pilot study, we examined neural activity during an explicitly cerebellar task in individuals with schizophrenia or schizoaffective disorder and non-psychiatric controls. Participants underwent delay eyeblink conditioning during fMRI. Results indicated eyeblink conditioning impairment in patients as evidenced by a group by time interaction for conditioned responses. A significant cluster of cerebellar activation was present in controls but not patients during the first half of conditioning; there were no significant differences in activation between groups. An ROI analysis focused on the cerebellum in patients revealed two significant clusters that were inversely associated with negative symptom severity. These results are broadly consistent with the theory of cognitive dysmetria, wherein cerebellar abnormalities are theorized to contribute to motor as well as cognitive and affective disturbances in schizophrenia.


Assuntos
Piscadela , Cerebelo/fisiopatologia , Condicionamento Palpebral/fisiologia , Esquizofrenia/fisiopatologia , Adulto , Cerebelo/diagnóstico por imagem , Condicionamento Clássico/fisiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Projetos Piloto , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/diagnóstico por imagem
16.
Comput Struct Biotechnol J ; 18: 1761-1773, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32695269

RESUMO

The brain is a complex network. Growing evidence supports the critical roles of a set of brain regions within the brain network, known as the brain's cores or hubs. These regions require high energy cost but possess highly efficient neural information transfer in the brain's network and are termed the rich-club. The rich-club of the brain network is essential as it directly regulates functional integration across multiple segregated regions and helps to optimize cognitive processes. Here, we review the recent advances in rich-club organization to address the fundamental roles of the rich-club in the brain and discuss how these core brain regions affect brain development and disorders. We describe the concepts of the rich-club behind network construction in the brain using graph theoretical analysis. We also highlight novel insights based on animal studies related to the rich-club and illustrate how human studies using neuroimaging techniques for brain development and psychiatric/neurological disorders may be relevant to the rich-club phenomenon in the brain network.

17.
Hum Brain Mapp ; 41(11): 3119-3132, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32250008

RESUMO

Abnormalities of cerebellar function have been implicated in the pathophysiology of schizophrenia. Since the cerebellum has afferent and efferent projections to diverse brain regions, abnormalities in cerebellar lobules could affect functional connectivity with multiple functional systems in the brain. Prior studies, however, have not examined the relationship of individual cerebellar lobules with motor and nonmotor resting-state functional networks. We evaluated these relationships using resting-state fMRI in 30 patients with a schizophrenia-spectrum disorder and 37 healthy comparison participants. For connectivity analyses, the cerebellum was parcellated into 18 lobular and vermal regions, and functional connectivity of each lobule to 10 major functional networks in the cerebrum was evaluated. The relationship between functional connectivity measures and behavioral performance on sensorimotor tasks (i.e., finger-tapping and postural sway) was also examined. We found cerebellar-cortical hyperconnectivity in schizophrenia, which was predominantly associated with Crus I, Crus II, lobule IX, and lobule X. Specifically, abnormal cerebellar connectivity was found to the cerebral ventral attention, motor, and auditory networks. This cerebellar-cortical connectivity in the resting-state was differentially associated with sensorimotor task-based behavioral measures in schizophrenia and healthy comparison participants-that is, dissociation with motor network and association with nonmotor network in schizophrenia. These findings suggest that functional association between individual cerebellar lobules and the ventral attentional, motor, and auditory networks is particularly affected in schizophrenia. They are also consistent with dysconnectivity models of schizophrenia suggesting cerebellar contributions to a broad range of sensorimotor and cognitive operations.


Assuntos
Cerebelo/fisiopatologia , Córtex Cerebral/fisiopatologia , Conectoma , Rede Nervosa/fisiopatologia , Desempenho Psicomotor/fisiologia , Transtornos Psicóticos/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Rede Nervosa/diagnóstico por imagem , Equilíbrio Postural/fisiologia , Transtornos Psicóticos/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Córtex Sensório-Motor/diagnóstico por imagem , Córtex Sensório-Motor/fisiopatologia , Adulto Jovem
18.
Pancreatology ; 20(2): 199-204, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31899135

RESUMO

BACKGROUND: and study aims: Chronic pancreatitis is associated with recurrent or persistent abdominal pain over the course of the disease. Ductal hypertension showing obstructed and dilated pancreatic duct has been suggested as a major factor in the mechanism of pain in chronic pancreatitis. Many studies investigating pain relief after endoscopic treatment of pancreatic duct (PD) are available, but the number of studies regarding the morphological changes to pancreas such as changes in PD caliber, pancreatic parenchyma, and especially pancreatic volume is far fewer. As such, we analyzed the changes of ductal caliber and parenchymal volume after endoscopic treatment of PD in patients with obstructive chronic pancreatitis. PATIENTS AND METHODS: In this retrospective study, we compared two groups of patients with obstructive chronic pancreatitis that either received endoscopic management of PD or conservative treatment without such endoscopic management. After we obtained age, sex, etiology of chronic pancreatitis, diabetic status, smoking and alcohol abuse status from the database, we compared the incidence for changes in pancreatic parenchymal volume and PD caliber between two groups. RESULT: In our study population, total of 480 patients was diagnosed with chronic pancreatitis between January 2006 and December 2016, and 166 (34.5%) of these patients were diagnosed with obstructive chronic pancreatitis with obstructed and dilated PD. After reviewing the population with the exclusion criteria, 71 patients were available for the final analysis. 28 of those patient received endoscopic treatment of pancreatic duct and 43 received conservative treatment without any endoscopic treatment of PD. Statistical analysis with Cox proportional hazards models showed that diabetes and endoscopic PD management were significant predictors for progression of PD caliber and in pancreatic parenchyma, and that only PD management influenced the pancreatic volume loss. CONCLUSION: Endoscopic management of PD in obstructive chronic pancreatitis have advantages on morphologic change such as pancreatic volume loss and progression of PD caliber in long follow-up period.


Assuntos
Colangiopancreatografia Retrógrada Endoscópica/métodos , Pancreatite Crônica/cirurgia , Adulto , Tratamento Conservador , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Manejo da Dor , Pâncreas/patologia , Pancreatite Crônica/patologia , Estudos Retrospectivos , Resultado do Tratamento
19.
Child Dev ; 91(2): e432-e450, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31073997

RESUMO

Prenatal maternal stress predicts subsequent elevations in youth depressive symptoms, but the neural processes associated with these links are unclear. This study evaluated whether prenatal maternal stress is associated with child brain development, and adolescent depressive symptoms using a prospective design with 74 mother child pairs (40 boys). Maternal stress was assessed during pregnancy, child cortical thickness at age 7, and depressive symptoms at age 12. Prenatal maternal stress was associated with less cortical thickness primarily in frontal and temporal regions and with elevated depressive symptoms; child cortical thickness additionally correlated with adolescent depressive symptoms. The observed associations are consistent with the possibility that cortical thickness in superior frontal regions links associations between prenatal maternal stress and adolescent depressive symptoms.


Assuntos
Córtex Cerebral/patologia , Depressão/fisiopatologia , Efeitos Tardios da Exposição Pré-Natal/patologia , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Estresse Psicológico , Adolescente , Criança , Feminino , Humanos , Masculino , Gravidez , Estudos Prospectivos
20.
Brain Imaging Behav ; 14(5): 2062-2071, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31302844

RESUMO

Human and animal studies have shown that heavy cannabis (CB) use interacts with glutamatergic signaling. Additionally, recent studies have suggested that glutamate (Glu) may drive resting state functional connectivity (RSfc). The aims of the current preliminary study were to: 1) determine whether dorsal anterior cingulate cortex (dACC) Glu is related to RSfc between the dACC and two nodes of the reward network, the nucleus accumbens (NAc) and hippocampus (Hp); and 2) determine whether CB use interacts with the relationship between dACC Glu and RSfc. A group of 23 chronic CB users and 23 healthy controls participated in this multimodal MRI study. Glu levels were assessed in the dACC using magnetic resonance spectroscopy (MRS). Linear regression models were used to determine whether dACC Glu and CB use predicts RSfc between the dACC and the NAc and Hp. While the effect size is small, the results showed that the connectivity between the dACC and right NAc was predicted by the interaction between dACC Glu levels and monthly CB use. Additionally, while there is some suggestion that dACC Glu is correlated with dACC-hippocampal connectivity, unlike for dACC/NAc connectivity the relationship between them does not appear to be affected by CB use. These preliminary findings are significant in that they demonstrate the need for future studies with larger sample sizes to better characterize the relationship between resting state connectivity and neurochemistry as well as to characterize how CB use interacts with that relationship.


Assuntos
Cannabis , Ácido Glutâmico/metabolismo , Giro do Cíngulo/fisiologia , Fumar Maconha/metabolismo , Descanso/fisiologia , Feminino , Humanos , Espectroscopia de Ressonância Magnética , Masculino , Adulto Jovem
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