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1.
Anal Sci ; 40(3): 489-499, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38165524

RESUMO

In our study, we present an innovative method for the analysis and real-time monitoring of peracetic acid (PAA) formation within the near-UV/Vis (visible) wavelength region. PAA's absorption spectrum, influenced by its presence in a complex quaternary equilibrium mixture with hydrogen peroxide (H2O2), acetic acid, and water, lacks discernible peaks. This inherent complexity challenges conventional analytical techniques like Beer's law, which rely on absorption intensity as a foundation. To address this challenge, we introduce a novel approach that centers on the analysis of blue shifts in absorption wavelengths, particularly at an absorbance of 0.8 a.u. This method significantly enhances the precision of calibration curves for both diluted PAA and H2O2, unveiling an exponential correlation between wavelength and the logarithm of concentration for both components. Significantly, our approach allows for real-time and accurate measurements, especially during the dynamic PAA formation reaction. Our results exhibit excellent agreement with data obtained from Fourier-transform infrared (FT-IR) spectroscopy, validating the reliability of our method. It's noteworthy that under stable PAA concentration conditions (after 12 h of solution interaction), both traditional absorption method and our approach closely align with the FT-IR method. However, in dynamic scenarios (0-12 h), the absorption method exhibits higher error rates compared to our approach. Additionally, the increased concentration of a catalyst, sulfuric acid (H2SO4), significantly reduces the errors in both methods, a finding that warrants further exploration. In summary, our study not only advances our understanding of PAA and its spectral behavior but also introduces innovative and precise methods for determining PAA concentration in complex solutions. These advancements hold the potential to revolutionize the field of chemical analysis and spectroscopy.

2.
Psychiatry Res ; 323: 115122, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36889161

RESUMO

OBJECTIVE: This paper aims to model the anatomical circuits underlying schizophrenia symptoms, and to explore patterns of abnormal connectivity among brain networks affected by psychopathology. METHODS: T1 magnetic resonance imaging (MRI), diffusion weighted imaging (DWI), and resting-state functional MRI (rsfMRI) were obtained from a total of 126 patients with schizophrenia who were recruited for the study. The images were processed using the Omniscient software (https://www.o8t. com). We further apply the use of the Hollow-tree Super (HoTS) method to gain insights into what brain regions had abnormal connectivity that might be linked to the symptoms of schizophrenia. RESULTS: The Positive and Negative Symptom Scale is characterised into 6 factors. Each symptom is mapped with specific anatomical abnormalities and circuits. Comparison between factors reveals co-occurrence in parcels in Factor 1 and Factor 2. Multiple large-scale networks are involved in SCZ symptomatology, with functional connectivity within Default Mode Network (DMN) and Central Executive Network (CEN) regions most frequently associated with measures of psychopathology. CONCLUSION: We present a summary of the relevant anatomy for regions of the cortical areas as part of a larger effort to understand its contribution in schizophrenia. This unique machine learning-type approach maps symptoms to specific brain regions and circuits by bridging the diagnostic subtypes and analysing the features of the connectome.


Assuntos
Conectoma , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico por imagem , Conectoma/métodos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética , Psicopatologia , Rede Nervosa/diagnóstico por imagem
3.
Brain Commun ; 4(3): fcac140, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35706977

RESUMO

The Gerstmann syndrome is a constellation of neurological deficits that include agraphia, acalculia, left-right discrimination and finger agnosia. Despite a growing interest in this clinical phenomenon, there remains controversy regarding the specific neuroanatomic substrates involved. Advancements in data-driven, computational modelling provides an opportunity to create a unified cortical model with greater anatomic precision based on underlying structural and functional connectivity across complex cognitive domains. A literature search was conducted for healthy task-based functional MRI and PET studies for the four cognitive domains underlying Gerstmann's tetrad using the electronic databases PubMed, Medline, and BrainMap Sleuth (2.4). Coordinate-based, meta-analytic software was utilized to gather relevant regions of interest from included studies to create an activation likelihood estimation (ALE) map for each cognitive domain. Machine-learning was used to match activated regions of the ALE to the corresponding parcel from the cortical parcellation scheme previously published under the Human Connectome Project (HCP). Diffusion spectrum imaging-based tractography was performed to determine the structural connectivity between relevant parcels in each domain on 51 healthy subjects from the HCP database. Ultimately 102 functional MRI studies met our inclusion criteria. A frontoparietal network was found to be involved in the four cognitive domains: calculation, writing, finger gnosis, and left-right orientation. There were three parcels in the left hemisphere, where the ALE of at least three cognitive domains were found to be overlapping, specifically the anterior intraparietal area, area 7 postcentral (7PC) and the medial intraparietal sulcus. These parcels surround the anteromedial portion of the intraparietal sulcus. Area 7PC was found to be involved in all four domains. These regions were extensively connected in the intraparietal sulcus, as well as with a number of surrounding large-scale brain networks involved in higher-order functions. We present a tractographic model of the four neural networks involved in the functions which are impaired in Gerstmann syndrome. We identified a 'Gerstmann Core' of extensively connected functional regions where at least three of the four networks overlap. These results provide clinically actionable and precise anatomic information which may help guide clinical translation in this region, such as during resective brain surgery in or near the intraparietal sulcus, and provides an empiric basis for future study.

4.
Brain Behav ; 12(7): e2646, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35733239

RESUMO

BACKGROUND: The salience network (SN) is a transitory mediator between active and passive states of mind. Multiple cortical areas, including the opercular, insular, and cingulate cortices have been linked in this processing, though knowledge of network connectivity has been devoid of structural specificity. OBJECTIVE: The current study sought to create an anatomically specific connectivity model of the neural substrates involved in the salience network. METHODS: A literature search of PubMed and BrainMap Sleuth was conducted for resting-state and task-based fMRI studies relevant to the salience network according to PRISMA guidelines. Publicly available meta-analytic software was utilized to extract relevant fMRI data for the creation of an activation likelihood estimation (ALE) map and relevant parcellations from the human connectome project overlapping with the ALE data were identified for inclusion in our SN model. DSI-based fiber tractography was then performed on publicaly available data from healthy subjects to determine the structural connections between cortical parcellations comprising the network. RESULTS: Nine cortical regions were found to comprise the salience network: areas AVI (anterior ventral insula), MI (middle insula), FOP4 (frontal operculum 4), FOP5 (frontal operculum 5), a24pr (anterior 24 prime), a32pr (anterior 32 prime), p32pr (posterior 32 prime), and SCEF (supplementary and cingulate eye field), and 46. The frontal aslant tract was found to connect the opercular-insular cluster to the middle cingulate clusters of the network, while mostly short U-fibers connected adjacent nodes of the network. CONCLUSION: Here we provide an anatomically specific connectivity model of the neural substrates involved in the salience network. These results may serve as an empiric basis for clinical translation in this region and for future study which seeks to expand our understanding of how specific neural substrates are involved in salience processing and guide subsequent human behavior.


Assuntos
Córtex Cerebral , Conectoma , Mapeamento Encefálico , Córtex Cerebral/fisiologia , Conectoma/métodos , Lobo Frontal , Giro do Cíngulo , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiologia
5.
Radiol Case Rep ; 17(6): 2038-2042, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35432681

RESUMO

Colorectal cancer is one of the leading causes of cancer-associated morbidity and mortality in the world, with lower survival rates when metastases are present. We present a case of a 69-year-old man, diagnosed with metastatic rectal cancer to the lungs in 2015. Over the course of 5 years, he was treated with 4 microwave ablation procedures to both his lungs. Despite this, he does not have any local recurrence or any symptoms since he was first diagnosed 7 years ago. This case highlights the potential for microwave ablation to be used for curative intent in pulmonary metastases in colorectal cancer as an alternative to more invasive and complex procedures such as metastasectomies or lung resection, as well as the benefit of using microwave ablation for disease control to improve patients' quality of life.

6.
Brain Imaging Behav ; 16(2): 574-586, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34448064

RESUMO

Purpose Advances in neuroimaging have provided an understanding of the precuneus'(PCu) involvement in functions such as visuospatial processing and cognition. While the PCu has been previously determined to be apart of a higher-order default mode network (DMN), recent studies suggest the presence of possible dissociations from this model in order to explain the diverse functions the PCu facilitates, such as in episodic memory. An improved structural model of the white-matter anatomy of the PCu can demonstrate its unique cerebral connections with adjacent regions which can provide additional clarity on its role in integrating information across higher-order cerebral networks like the DMN. Furthermore, this information can provide clinically actionable anatomic information that can support clinical decision making to improve neurologic outcomes such as during cerebral surgery. Here, we sought to derive the relationship between the precuneus and underlying major white-mater bundles by characterizing its macroscopic connectivity. Methods Structural tractography was performed on twenty healthy adult controls from the Human Connectome Project (HCP) utilizing previously demonstrated methodology. All precuneus connections were mapped in both cerebral hemispheres and inter-hemispheric differences in resultant tract volumes were compared with an unpaired, corrected Mann-Whitney U test and a laterality index (LI) was completed. Ten postmortem dissections were then performed to serve as ground truth by using a modified Klingler technique with careful preservation of relevant white matter bundles. Results The precuneus is a heterogenous cortical region with five major types of connections that were present bilaterally. (1) Short association fibers connect the gyri of the precuneus and connect the precuneus to the superior parietal lobule and the occipital cortex. (2) Four distinct parts of the cingulum bundle connect the precuneus to the frontal lobe and the temporal lobe. (3) The middle longitudinal fasciculus from the precuneus connects to the superior temporal gyrus and the dorsolateral temporal pole. (4) Parietopontine fibers travel as part of the corticopontine fibers to connect the precuneus to pontine regions. (5) An extensive commissural bundle connects the precuneus bilaterally. Conclusion We present a summary of the anatomic connections of the precuneus as part of an effort to understand the function of the precuneus and highlight key white-matter pathways to inform surgical decision-making. Our findings support recent models suggesting unique fiber connections integrating at the precuneus which may suggest finer subsystems of the DMN or unique networks, but further study is necessary to refine our model in greater quantitative detail.


Assuntos
Conectoma , Substância Branca , Adulto , Humanos , Imageamento por Ressonância Magnética , Vias Neurais/anatomia & histologia , Vias Neurais/diagnóstico por imagem , Lobo Parietal/anatomia & histologia , Lobo Parietal/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem
7.
Oper Neurosurg (Hagerstown) ; 21(3): E199-E214, 2021 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-34246196

RESUMO

BACKGROUND: The superior parietal lobule (SPL) is involved in somatosensory and visuospatial integration with additional roles in attention, written language, and working memory. A detailed understanding of the exact location and nature of associated white matter tracts could improve surgical decisions and subsequent postoperative morbidity related to surgery in and around this gyrus. OBJECTIVE: To characterize the fiber tracts of the SPL based on relationships to other well-known neuroanatomic structures through diffusion spectrum imaging (DSI)-based fiber tracking validated by gross anatomical dissection as ground truth. METHODS: Neuroimaging data of 10 healthy, adult control subjects was obtained from a publicly accessible database published in Human Connectome Project for subsequent tractographic analyses. White matter tracts were mapped between both cerebral hemispheres, and a lateralization index was calculated based on resultant tract volumes. Post-mortem dissections of 10 cadavers identified the location of major tracts and validated our tractography results based on qualitative visual agreement. RESULTS: We identified 9 major connections of the SPL: U-fiber, superior longitudinal fasciculus, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, middle longitudinal fasciculus, extreme capsule, vertical occipital fasciculus, cingulum, and corpus callosum. There was no significant fiber lateralization detected. CONCLUSION: The SPL is an important region implicated in a variety of tasks involving visuomotor and visuospatial integration. Improved understanding of the fiber bundle anatomy elucidated in this study can provide invaluable information for surgical treatment decisions related to this region.


Assuntos
Conectoma , Substância Branca , Adulto , Humanos , Rede Nervosa , Vias Neurais/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
8.
Clin Neurol Neurosurg ; 207: 106792, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34233235

RESUMO

PURPOSE: Venous thromboembolism (VTE) is a well-known problem in patients with intracranial tumors, especially high-grade gliomas. Optimal management of VTE complications is critical given that the development of deep vein thrombosis (DVT) and/or pulmonary embolism can exacerbate medical comorbidities and increase mortality. However, little is known about the optimum time to initiate post-operative anticoagulant prophylaxis. Therefore, there is a keen interest amongst neurosurgeons to develop evidence-based protocols to prevent VTE in post-operative brain tumor patients. METHODS: We retrospectively identified adult patients who underwent elective craniotomy for intracranial tumor resection between 2012 and 2017. Patients were categorized according to the time at which they began receiving prophylactic enoxaparin in the immediate post-operative period, within one day (POD 1), two days (POD 2), three days (POD 3), five days (POD 5), or seven days (POD 7). RESULTS: A total of 1087 patients had a craniotomy for intracranial tumor resection between 2012 and 2017. Multivariate binomial logistic regression analysis demonstrated that initiation of prophylactic enoxaparin within 72 h of surgery was protective against the likelihood of developing a lower extremity DVT (OR: 0.32; CI: 0.10-0.95; p = 0.049) while controlling for possible risk factors for DVTs identified on univariate analysis. Furthermore, complication rates between the anticoagulation and non-anticoagulation groups were not statistically significant. CONCLUSION: Initiating anticoagulant prophylaxis with subcutaneous enoxaparin sodium 40 mg once per day within 72 h of surgery can be done safely while reducing the risk of developing lower extremity DVT.


Assuntos
Anticoagulantes/administração & dosagem , Neoplasias Encefálicas/cirurgia , Enoxaparina/análogos & derivados , Trombose Venosa/prevenção & controle , Adulto , Craniotomia/efeitos adversos , Enoxaparina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Trombose Venosa/etiologia
9.
Oper Neurosurg (Hagerstown) ; 21(1): E8-E14, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-33929019

RESUMO

BACKGROUND: The middle temporal gyrus (MTG) is understood to play a role in language-related tasks such as lexical comprehension and semantic cognition. However, a more specific understanding of its key white matter connections could promote the preservation of these functions during neurosurgery. OBJECTIVE: To provide a detailed description of the underlying white matter tracts associated with the MTG to improve semantic preservation during neurosurgery. METHODS: Tractography was performed using diffusion imaging obtained from 10 healthy adults from the Human Connectome Project. All tracts were mapped between cerebral hemispheres with a subsequent laterality index calculated based on resultant tract volumes. Ten postmortem dissections were performed for ex vivo validation of the tractography based on qualitative visual agreement. RESULTS: We identified 2 major white matter bundles leaving the MTG: the inferior longitudinal fasciculus and superior longitudinal fasciculus. In addition to long association fibers, a unique linear sequence of U-shaped fibers was identified, possibly representing a form of visual semantic transfer down the temporal lobe. CONCLUSION: We elucidate the underlying fiber-bundle anatomy of the MTG, an area highly involved in the brain's language network. Improved understanding of the unique, underlying white matter connections in and around this area may augment our overall understanding of language processing as well as the involvement of higher order cerebral networks like the default mode network in these functions.


Assuntos
Conectoma , Substância Branca , Adulto , Humanos , Rede Nervosa , Vias Neurais/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
10.
World Neurosurg ; 150: e520-e529, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33744423

RESUMO

BACKGROUND: The middle frontal gyrus (MFG) is involved in attention, working memory, and language-related processing. A detailed understanding of the subcortical white matter tracts connected within the MFG can facilitate improved navigation of white matter lesions in and around this gyrus and explain the postoperative morbidity after surgery. We aimed to characterize the fiber tracts within the MFG according to their connection to neuroanatomic structures through the use of diffusion spectrum imaging-based fiber tractography and validate the findings by gross anatomic dissection for qualitative visual agreement. METHODS: Tractography analysis was completed using diffusion imaging data from 10 healthy, adult subjects enrolled in the Human Connectome Project. We assessed the MFG as a whole component according to its fiber connectivity with other neural regions. Mapping was completed on all tracts within both hemispheres, with the resultant tract volumes used to calculate a lateralization index. A modified Klingler technique was used on 10 postmortem dissections to demonstrate the location and orientation of the major tracts. RESULTS: Two major connections of the MFG were identified: the superior longitudinal fasciculus, which connects the MFG to parts of the inferior parietal lobule, posterior temporal lobe, and lateral occipital cortex; and the inferior fronto-occipital fasciculus, which connected the MFG to the lingual gyrus and cuneus. Intra- and intergyral short association, U-shaped fibers were also identified. CONCLUSIONS: Subcortical white matter pathways integrated within the MFG include the superior longitudinal fasciculus and inferior fronto-occipital fasciculus. The MFG is implicated in a variety of tasks involving attention and memory, making it an important cortical region. The postoperative neurologic outcomes related to surgery in and around the MFG could be clarified in the context of the anatomy of the fiber bundles highlighted in the present study.


Assuntos
Vias Neurais/anatomia & histologia , Córtex Pré-Frontal/anatomia & histologia , Substância Branca/anatomia & histologia , Imagem de Tensor de Difusão/métodos , Humanos
11.
Brain Behav ; 11(4): e02065, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33599397

RESUMO

INTRODUCTION: The semantic network is an important mediator of language, enabling both speech production and the comprehension of multimodal stimuli. A major challenge in the field of neurosurgery is preventing semantic deficits. Multiple cortical areas have been linked to semantic processing, though knowledge of network connectivity has lacked anatomic specificity. Using attentional task-based fMRI studies, we built a neuroanatomical model of this network. METHODS: One hundred and fifty-five task-based fMRI studies related to categorization of visual words and objects, and auditory words and stories were used to generate an activation likelihood estimation (ALE). Cortical parcellations overlapping the ALE were used to construct a preliminary model of the semantic network based on the cortical parcellation scheme previously published under the Human Connectome Project. Deterministic fiber tractography was performed on 25 randomly chosen subjects from the Human Connectome Project, to determine the connectivity of the cortical parcellations comprising the network. RESULTS: The ALE analysis demonstrated fourteen left hemisphere cortical regions to be a part of the semantic network: 44, 45, 55b, IFJa, 8C, p32pr, SFL, SCEF, 8BM, STSdp, STSvp, TE1p, PHT, and PBelt. These regions showed consistent interconnections between parcellations. Notably, the anterior temporal pole, a region often implicated in semantic function, was absent from our model. CONCLUSIONS: We describe a preliminary cortical model for the underlying structural connectivity of the semantic network. Future studies will further characterize the neurotractographic details of the semantic network in the context of medical application.


Assuntos
Conectoma , Web Semântica , Mapeamento Encefálico , Humanos , Imageamento por Ressonância Magnética , Modelos Anatômicos , Semântica , Fala
12.
J Neurol Sci ; 421: 117322, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33497952

RESUMO

INTRODUCTION: The supplementary motor area (SMA) plays an important role in the initiation and coordination of internally and externally cued movements. Such movements include reaching, grasping, speaking, and bilateral hand coordination. While many studies discuss the SMA and its relationship to other parts of the motor network, there is minimal literature examining the connectivity of the SMA outside of the motor network. Using region-based fMRI studies, we built a neuroanatomical model to account for these extra-motor connections. METHODS: Thirty region-based fMRI studies were used to generate an activation likelihood estimation (ALE) using BrainMap software. Cortical parcellations overlapping the ALE were used to construct a preliminary model of the SMA connections outside the motor network. DSI-based fiber tractography was performed to determine the connectivity between cortical parcellations. The resulting connections were described using the cortical parcellation scheme developed by the Human Connectome Project (HCP). RESULTS: Four left hemisphere regions were found to comprise the SMA. These included areas SFL, SCEF, 6ma, and 6mp. Across mapped brains, these areas showed consistent interconnections between each other. Additionally, ipsilateral connections to the primary motor cortex, left inferior and middle frontal gyri, the anterior cingulate gyrus, and insula were demonstrated. Connections to the contralateral SMA, anterior cingulate, lateral premotor, and inferior frontal cortices were also identified. CONCLUSIONS: We describe a preliminary cortical model for the underlying structural connectivity of the supplementary motor area outside the motor network. Future studies should further characterize the neuroanatomic underpinnings of this network for the purposes of medical application.


Assuntos
Conectoma , Córtex Motor , Mapeamento Encefálico , Giro do Cíngulo , Mãos , Humanos , Imageamento por Ressonância Magnética , Córtex Motor/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem
13.
World Neurosurg ; 148: e218-e226, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33412321

RESUMO

BACKGROUND: The parahippocampal gyrus is understood to have a role in high cognitive functions including memory encoding and retrieval and visuospatial processing. A detailed understanding of the exact location and nature of associated white tracts could significantly improve postoperative morbidity related to declining capacity. Through diffusion tensor imaging-based fiber tracking validated by gross anatomic dissection as ground truth, we have characterized these connections based on relationships to other well-known structures. METHODS: Diffusion imaging from the Human Connectome Project for 10 healthy adult controls was used for tractography analysis. We evaluated the parahippocampal gyrus as a whole based on connectivity with other regions. All parahippocampal gyrus tracts were mapped in both hemispheres, and a lateralization index was calculated with resultant tract volumes. RESULTS: We identified 2 connections of the parahippocampal gyrus: inferior longitudinal fasciculus and cingulum. Lateralization of the cingulum was detected (P < 0.05). CONCLUSIONS: The parahippocampal gyrus is an important center for memory processing. Subtle differences in executive functioning following surgery for limbic tumors may be better understood in the context of the fiber-bundle anatomy highlighted by this study.


Assuntos
Rede Nervosa/anatomia & histologia , Rede Nervosa/diagnóstico por imagem , Giro Para-Hipocampal/anatomia & histologia , Giro Para-Hipocampal/diagnóstico por imagem , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagem , Adulto , Conectoma/métodos , Imagem de Tensor de Difusão/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Brain Behav ; 11(2): e01976, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33337028

RESUMO

BACKGROUND: The default mode network (DMN) is an important mediator of passive states of mind. Multiple cortical areas, such as the anterior cingulate cortex, posterior cingulate cortex, and lateral parietal lobe, have been linked in this processing, though knowledge of network connectivity had limited tractographic specificity. METHODS: Using resting-state fMRI studies related to the DMN, we generated an activation likelihood estimation (ALE). We built a tractographical model of this network based on the cortical parcellation scheme previously published under the Human Connectome Project. DSI-based fiber tractography was performed to determine the structural connections between cortical parcellations comprising the network. RESULTS: Seventeen cortical regions were found to be part of the DMN: 10r, 31a, 31pd, 31pv, a24, d23ab, IP1, p32, POS1, POS2, RSC, PFm, PGi, PGs, s32, TPOJ3, and v23ab. These regions showed consistent interconnections between adjacent parcellations, and the cingulum was found to connect the anterior and posterior cingulate clusters within the network. CONCLUSIONS: We present a preliminary anatomic model of the default mode network. Further studies may refine this model with the ultimate goal of clinical application.


Assuntos
Conectoma , Rede de Modo Padrão , Humanos , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Lobo Parietal
15.
Biomed Microdevices ; 22(3): 60, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32870410

RESUMO

Glioblastoma (GBM) is one of the most malignant primary brain tumors. This neoplasm is the hardest to treat and has a bad prognosis. Because of the characteristics of genetic heterogeneity and frequent recurrence, a successful cure for the disease is unlikely. Increasing evidence has revealed that the GBM stem cell-like cells (GSCs) and microenvironment are key elements in GBM recurrence and treatment failure. To better understand the mechanisms underlying this disease and to develop more effective therapeutic strategies for treatment, suitable approaches, techniques, and model systems closely mimicking real GBM conditions are required. Microfluidic devices, a model system mimicking the in vivo brain microenvironment, provide a very useful tool to analyze GBM cell behavior, their correlation with tumor malignancy, and the efficacy of multiple drug treatment. This paper reviews the applications of microfluidic devices in GBM research and summarizes progress and perspectives in this field.


Assuntos
Glioblastoma , Dispositivos Lab-On-A-Chip , Animais , Humanos
16.
Hear Res ; 396: 108078, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32961519

RESUMO

INTRODUCTION: The auditory network plays an important role in interaction with the environment. Multiple cortical areas, such as the inferior frontal gyrus, superior temporal gyrus and adjacent insula have been implicated in this processing. However, understanding of this network's connectivity has been devoid of tractography specificity. METHODS: Using attention task-based functional magnetic resonance imaging (MRI) studies, an activation likelihood estimation (ALE) of the auditory network was generated. Regions of interest corresponding to the cortical parcellation scheme previously published under the Human Connectome Project were co-registered onto the ALE in the Montreal Neurological Institute coordinate space, and visually assessed for inclusion in the network. Diffusion spectrum MRI-based fiber tractography was performed to determine the structural connections between cortical parcellations comprising the network. RESULTS: Fifteen cortical regions were found to be part of the auditory network: areas 44 and 8C, auditory area 1, 4, and 5, frontal operculum area 4, the lateral belt, medial belt and parabelt, parietal area F centromedian, perisylvian language area, retroinsular cortex, supplementary and cingulate eye field and the temporoparietal junction area 1. These regions showed consistent interconnections between adjacent parcellations. The frontal aslant tract was found to connect areas within the frontal lobe, while the arcuate fasciculus was found to connect the frontal and temporal lobe, and subcortical U-fibers were found to connect parcellations within the temporal area. Further studies may refine this model with the ultimate goal of clinical application.


Assuntos
Córtex Auditivo , Conectoma , Córtex Auditivo/diagnóstico por imagem , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética , Rede Nervosa , Vias Neurais/diagnóstico por imagem
17.
World Neurosurg ; 143: e656-e666, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32798785

RESUMO

BACKGROUND: The inferior temporal gyrus (ITG) is known to be involved in high-cognitive functions, including visual and language comprehensions and emotion regulation. A detailed understanding of the nature of association fibers could significantly improve postoperative morbidity related to declining capacity. Through diffusion spectrum imaging-based fiber tracking, we have characterized these connections on the basis of their relationships to other cortical areas. METHODS: Diffusion spectrum images from 10 healthy adults of the Human Connectome Project were randomly selected and used for tractography analysis. We evaluated the ITG as a whole based on connectivity with other regions. All ITG tracts were mapped in both hemispheres, and a lateralization index was calculated with resultant tract volumes. RESULTS: We identified 5 major connections of the ITG: U-fiber, inferior longitudinal fasciculus, vertical occipital fasciculus, arcuate fasciculus, and uncinate fasciculus. There was no fiber lateralization detected. CONCLUSIONS: This study highlights the principal white-matter pathways of the ITG and demonstrates key underlying connections. We present a summary of the relevant clinical anatomy for this region of the cerebrum as part of a larger effort to understand it in its entirety.


Assuntos
Conectoma/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Rede Nervosa/anatomia & histologia , Lobo Temporal/anatomia & histologia , Substância Branca/anatomia & histologia , Adulto , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
18.
Eur Spine J ; 29(11): 2688-2700, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32279116

RESUMO

PURPOSE: Although cervical total disc replacement (CTDR) is perceived as a safe procedure, no review to date has quantified the complication rates. Of note, heterotopic ossification (HO), one of the complications of CTDR, is hypothesised to cause adjacent segment degeneration (ASDegeneration). This association has not been proven in meta-analysis. Hence, this systematic review and meta-analysis aims to investigate the pooled prevalence of complications following CTDR among studies that concomitantly reported the rate of HO, and the associations between HO and other complications, including ASDegeneration. METHODS: Literatures search was conducted in Embase, MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials. Complications were stratified into ≥ 1 and < 2 years, ≥ 2 and < 5 years, and ≥ 5 years follow-up. Subgroup and meta-regression analyses were performed. RESULTS: Fifty-three studies were included, composed of 3223 patients in total. The pooled prevalence of post-operative complications following CTDR was low, ranging from 0.8% in vascular adverse events to 4.7% in dysphagia at short-term follow-up. The rate of ASDegeneration was significantly higher at long-term follow-up (pooled prevalence 36.0%, 95% confidence interval [CI] 22.8-49.1%) than that at mid-term follow-up (pooled prevalence 7.3%, 95% CI 2.8-11.8%). Multivariate meta-regression analysis demonstrated that ASDegeneration was independently and inversely correlated with age (p = 0.007) and positively correlated with HO (p = 0.010) at mid-term follow-up. At long-term follow-up, ASDegeneration was still positively correlated with HO (p = 0.011), but not age. Furthermore, dysphagia was inversely associated with HO (p = 0.016), after adjustment for age and length of follow-up. CONCLUSION: In conclusion, HO is associated with ASDegeneration and dysphagia.


Assuntos
Degeneração do Disco Intervertebral , Ossificação Heterotópica , Substituição Total de Disco , Vértebras Cervicais/cirurgia , Humanos , Degeneração do Disco Intervertebral/epidemiologia , Degeneração do Disco Intervertebral/cirurgia , Pescoço , Ossificação Heterotópica/epidemiologia , Ossificação Heterotópica/etiologia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Substituição Total de Disco/efeitos adversos , Resultado do Tratamento
19.
Oncotarget ; 8(55): 93712-93728, 2017 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-29212184

RESUMO

Cordyceps militaris (CM) and its active ingredient cordycepin have been reported to inhibit tumor growth, but the mechanisms are not fully understood. This study used a mouse model for oral cancer and a cell line, 4NAOC-1 derived from the model to study the mechanisms. Our results show that a CM preparation (CMP) can significantly inhibit tumor development and malignant transformation in the model. In vitro data indicate that CMP and cordycepin can inhibit 4NAOC-1 cell proliferation, either anchorage-dependent or -independent. Cordycepin can also increase cell apoptosis, and decrease cell mitosis and EGFR signaling. In accordance, CMP treatment can significantly decrease the levels of ki-67 and EGFR signaling molecules in cancer tissues. We also found that the levels of IL-17A in cancer tissues of control mice were significantly increased, and CMP inhibited these levels. IL-17A can stimulate cancer cell proliferation, which can be suppressed by cordycepin. Furthermore, cordycepin can reduce the expression of IL-17RA and its downstream signaling molecules. Moreover, CMP and cordycepin can significantly decrease IL-17A production in vitro and in vivo. Finally, CMP and its ingredients can enhance tumoricidal activities with increase in IFN-γ and TNFα, and decrease PD-L1 expression. In conclusion, CMP and its ingredient cordycepin can inhibit tumor growth and malignant transformation in a mouse model for oral cancer via inhibition of EGFR- and IL-17RA-signaling and enhancement of anti-tumor immunity.

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