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1.
Ther Adv Chronic Dis ; 15: 20406223241236258, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38496233

RESUMEN

Background: One-third of intractable epilepsy patients have no visually identifiable focus for neurosurgery based on imaging tests [magnetic resonance imaging (MRI)-negative cases]. Stereo-electroencephalography-guided radio-frequency thermocoagulation (SEEG-guided RF-TC) is utilized in the clinical treatment of epilepsy to lower the incidence of complications post-open surgery. Objective: This study aimed to identify prognostic factors and long-term seizure outcomes in SEEG-guided RF-TC for patients with MRI-negative epilepsy. Design: This was a single-center retrospective cohort study. Methods: We included 30 patients who had undergone SEEG-guided RF-TC at Sanbo Brain Hospital, Capital Medical University, from April 2015 to December 2019. The probability of remaining seizure-free and the plotted survival curves were analyzed. Prognostic factors were analyzed using log-rank tests in univariate analysis and the Cox regression model in multivariate analysis. Results: With a mean time of 31.07 ± 2.64 months (median 30.00, interquartile range: 18.00-40.00 months), 11 out of 30 patients (36.7%) were classified as International League Against Epilepsy class 1 in the last follow-up. The mean time of remaining seizure-free was 21.33 ± 4.55 months [95% confidence interval (CI) 12.41-30.25], and the median time was 3.00 ± 0.54 months (95% CI 1.94-4.06). Despite falling in the initial year, the probability of remaining seizure-free gradually stabilizes in the subsequent years. The patients were more likely to obtain seizure freedom when the epileptogenic zone was located in the insular lobe or with one focus on the limbic system (p = 0.034, hazard ratio 5.019, 95% CI 1.125-22.387). Conclusion: Our findings may be applied to guide individualized surgical interventions and help clinicians make better decisions.

2.
J Hazard Mater ; 435: 129022, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35500348

RESUMEN

A major environmental concern related to nuclear energy is wastewater contaminated with uranium, thus necessitating the development of pollutant-reducing materials with efficiency and effectiveness. Herein, highly selective mesoporous silicas functionalized with amine-bridged diacetamide ligands SBA-15-ABDMA were prepared. Different spectroscopy techniques were used to probe the chemical environment and reactivity of the chelating ligands before and after sorption. The results showed that the functionalized SBA-15-ABDMA had a strong affinity for uranium at low pH (pH = 3) with desirable sorption capacity (68.82 mg/g) and good reusability (> 5). It showed excellent separation performance with a high distribution coefficient (Kd,U > 105 mL/g) and separation factors SFU/Ln > 1000 at a pH of 3.5 in the presence of lanthanide nuclides, alkaline earth metal and transition metal ions. In particular, SiO2spheres-ABDMA was used as a column material, which achieved excellent recovery of U(VI) (> 98%) and good reusability for samples of simulated mining and nuclear industries wastewater. XPS and crystallography studies clearly illustrated the tridentate coordination mode of U(VI)/PEABDMA and the mechanism and origin behind the high selectivity for U.


Asunto(s)
Uranio , Adsorción , Aminas , Ligandos , Dióxido de Silicio/química , Uranio/química , Aguas Residuales
3.
Talanta ; 245: 123443, 2022 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-35405445

RESUMEN

U, Sr, Pb, Nd, and Hf isotope ratios can provide basic and important information of nuclear materials. We established a simple and efficient column chemistry method using nano-NaBiO3, as both oxidizer and adsorbent, to completely separate Ce from rare earth elements (REEs). This new method exhibited a high decontamination (Ce/Nd < 10-5) ability and was easy to conducted, thereby providing clear advantages compared to traditional liquid-liquid and solid phase micro-extraction techniques. Additionally, a rapid four-column separation procedure, based on Sr, TUR, Ln resins and nano-NaBiO3, was developed to isolate U, Sr, Pb, Nd, and Hf in ore samples. The entire procedure could be completed in 4-5 hrs. The robustness of the proposed method was demonstrated by analyzing the 235U/238U, 87Sr/86Sr, 206Pb/204Pb, 207Pb/204Pb, 208Pb/204Pb, 142Nd/144Nd, 143Nd/144Nd, and 176Hf/177Hf isotopic ratios of two certified reference materials (CRMs). The analytical results obtained using this method showed good agreement with previously published data. The feasibility of this method was extended to the determination of isotope ratios in uranium ores. The results obtained from the two samples with different regions indicated that they have different isotopic ratios information. These findings indicate the potential for the use of this new method in nuclear forensic science.


Asunto(s)
Uranio , Isótopos/análisis , Plomo , Uranio/análisis
4.
Neuroimage Clin ; 33: 102918, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34952352

RESUMEN

Volumetric magnetic resonance imaging (MRI) atrophy is a hallmark of Rasmussen's encephalitis (RE). Here, we aim to investigate voxel-wise gray matter (GM) atrophy in RE, and its associations with glucose hypometabolism and neurotransmitter distribution utilizing MRI and PET data. In this study, fifteen RE patients and fourteen MRI normal subjects were included in this study. Voxel-wise GM volume and glucose metabolic uptake were evaluated using structural MRI and FDG-PET images, respectively. Spatial Spearman's correlation was performed between GM atrophy of RE with FDG uptake alterations, and neurotransmitter distributions provided in the JuSpace toolbox. Compared with the control group, RE patients displayed extensive GM volume loss not only in the ipsilateral hemisphere, but also in the frontal lobe, basal ganglia, and cerebellum in the contralateral hemisphere. Within the RE group, the insular and temporal cortices exhibited significantly more GM atrophy on the ipsilesional than the contralesional side. FDG-PET data revealed significant hypometabolism in areas surrounding the insular cortices in the ipsilesional hemisphere. RE-related GM volumetric atrophy was spatially correlated with hypomebolism in FDG uptake, and with spatial distribution of the dopaminergic and serotonergic neurotransmitter systems. The spatial concordance of morphological changes with metabolic abnormalities suggest FDG-PET offers potential value for RE diagnosis. The GM alterations associated with neurotransmitter distribution map could provide novel insight in understanding the neuropathological mechanisms and clinical feature of RE.


Asunto(s)
Encefalitis , Imagen por Resonancia Magnética , Atrofia/patología , Encefalitis/diagnóstico por imagen , Encefalitis/patología , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Imagen por Resonancia Magnética/métodos , Metaboloma
5.
Front Neurol ; 12: 683299, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34721253

RESUMEN

Epilepsy is one of the most challenging neurologic diseases confronted by human society. Approximately 30-40% of the worldwide epilepsy patients are diagnosed with drug-resistant epilepsy and require pre-surgery evaluation. Magnetoencephalography (MEG) is a unique technology that provides optimal spatial-temporal resolution and has become a powerful non-invasive imaging modality that can localize the interictal spikes and guide the implantation of intracranial electrodes. Currently, the most widely used MEG source estimation method for clinical applications is equivalent current dipoles (ECD). However, ECD has difficulties in precisely locating deep sources such as insular lobe. In contrast to ECD, another MEG source estimation method named spatio-temporal unifying tomography (STOUT) with spatial sparsity has particular advantages in locating deep sources. In this case study, we recruited a 5 year-old female patient with insular lobe epilepsy and her seizure recurred in 1 year after receiving the radiofrequency thermocoagulation (RF-TC) therapy. The STOUT method was adopted to locate deep sources for identifying the epileptic foci in epilepsy evaluation. MEG STOUT method strongly supported a stereo-electroencephalographic (SEEG)-guided RF-TC operation, and the patient reported a satisfactory therapeutic effect. This case raises the possibility that STOUT method can be used particularly for the localization of deep sources, and successfully conducted RF-TC under the guidance of MEG STOUT results.

6.
Neurol Sci ; 42(1): 225-233, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32632633

RESUMEN

PURPOSE: Temporal lobe epilepsy patients treated with hippocampal deep brain stimulation (Hip-DBS) have rarely been reported before. Preoperative and postoperative cognitive function is seldom analyzed. METHODS: Seven patients with drug-resistant temporal lobe epilepsy were included in this study. Bilateral Hip-DBS was performed in these patients. The stimulator was activated 1 month after the implantation. Then, the patients returned for further adjustments 4 months after the surgery and reprogramming every year. The seizure frequency, Wechsler Adult Intelligence Scale-IV, and Wechsler memory scale-IV were assessed blindly as the outcomes at each follow-up. RESULTS: After a mean 48-month follow-up, the mean seizure frequency significantly decreased (p = 0.011, paired t test; decrease of 78.1%). One patient (14.3%) was seizure-free by the last follow-up; six of seven (85.7%) patients had reductions in seizure frequency of at least 50%; one patient (14.3%) who did not comply with the antiepileptic drug instructions had a less than 50% reduction in seizure frequency. In addition, there were no significant decreases in intelligence or verbal and visual memory from baseline to the last follow-up (p = 0.736, paired t test; p = 0.380, paired t test, respectively). CONCLUSION: Hip-DBS could provide acceptable long-term efficacy and safety. For patients with drug-resistant temporal lobe epilepsy who are not suitable for resective surgery, Hip-DBS could become a potential therapeutic option.


Asunto(s)
Estimulación Encefálica Profunda , Epilepsia del Lóbulo Temporal , Preparaciones Farmacéuticas , Adulto , Cognición , Epilepsia del Lóbulo Temporal/terapia , Hipocampo , Humanos , Resultado del Tratamiento
7.
J Neurosurg ; 134(3): 1019-1026, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32302977

RESUMEN

OBJECTIVE: In this study, the authors compared the efficacy and safety of stereotactic radiofrequency thermocoagulation (SRT) and resective surgery (RS) for patients with hypothalamic hamartoma (HH). METHODS: The authors included all patients with HHs who were treated by SRT or hamartoma resection. Seizure outcomes were assessed by blinded observers according to the International League Against Epilepsy (ILAE) classification. Favorable seizure outcomes were defined as ILAE classes 1 and 2, and unfavorable seizure outcomes were defined as ILAE classes 3-6. RESULTS: Twenty-nine patients who underwent SRT or RS met the inclusion criteria; 3 were excluded because they had completed less than 12 months of follow-up. Most of the patients (20 of 26; 76.9%) had small HHs (i.e., maximum HH diameter less than 20 mm). The patients' follow-up time ranged from 12 to 66 months (median 60 months). At the last follow-up, favorable outcomes were observed in 9 patients (69.2%) who had undergone SRT and 10 patients (76.9%) who had undergone HH resection. No significant difference was found in seizure outcomes between SRT and RS recipients. Patients with giant HHs were more likely than patients with smaller tumors to undergo multiple resections (p = 0.043, univariate logistic regression; significant). However, no significant difference was found between SRT and RS recipients in terms of the number of procedures per patient. SRT recipients had fewer and less-severe adverse events than RS recipients. CONCLUSIONS: For patients with small HHs, SRT provides similar seizure outcomes to RS with a less invasive procedure. Patients who underwent SRT experienced fewer and lighter adverse effects than patients who had RS. Patients with giant HHs were more likely to undergo multiple HH resections.


Asunto(s)
Electrocoagulación/métodos , Hamartoma/cirugía , Enfermedades Hipotalámicas/cirugía , Procedimientos Neuroquirúrgicos/métodos , Radiocirugia/métodos , Adolescente , Niño , Preescolar , Epilepsias Parciales , Femenino , Estudios de Seguimiento , Humanos , Imagen por Resonancia Magnética , Masculino , Complicaciones Posoperatorias/epidemiología , Convulsiones/etiología , Convulsiones/terapia , Resultado del Tratamiento , Adulto Joven
8.
Med Image Anal ; 56: 122-139, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31226662

RESUMEN

Breast cancer is the most common invasive cancer in women, affecting more than 10% of women worldwide. Microscopic analysis of a biopsy remains one of the most important methods to diagnose the type of breast cancer. This requires specialized analysis by pathologists, in a task that i) is highly time- and cost-consuming and ii) often leads to nonconsensual results. The relevance and potential of automatic classification algorithms using hematoxylin-eosin stained histopathological images has already been demonstrated, but the reported results are still sub-optimal for clinical use. With the goal of advancing the state-of-the-art in automatic classification, the Grand Challenge on BreAst Cancer Histology images (BACH) was organized in conjunction with the 15th International Conference on Image Analysis and Recognition (ICIAR 2018). BACH aimed at the classification and localization of clinically relevant histopathological classes in microscopy and whole-slide images from a large annotated dataset, specifically compiled and made publicly available for the challenge. Following a positive response from the scientific community, a total of 64 submissions, out of 677 registrations, effectively entered the competition. The submitted algorithms improved the state-of-the-art in automatic classification of breast cancer with microscopy images to an accuracy of 87%. Convolutional neuronal networks were the most successful methodology in the BACH challenge. Detailed analysis of the collective results allowed the identification of remaining challenges in the field and recommendations for future developments. The BACH dataset remains publicly available as to promote further improvements to the field of automatic classification in digital pathology.


Asunto(s)
Neoplasias de la Mama/patología , Redes Neurales de la Computación , Reconocimiento de Normas Patrones Automatizadas , Algoritmos , Femenino , Humanos , Microscopía , Coloración y Etiquetado
9.
World Neurosurg ; 120: e472-e479, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30149153

RESUMEN

OBJECTIVE: We elucidated the clinical and radiological characteristics and analyzed the risk factors for hemorrhage and poor outcomes of cerebral venous malformations (CVMs) in a northern Chinese population. METHODS: We included 60 consecutive patients with CVM patients in Beijing Tiantan Hospital from January 2011 to February 2018. The clinical manifestations, radiological characteristics, management, and outcomes were elucidated and analyzed. The patients were followed up for 5-64 months (median, 26). Poor outcomes included repeat bleeding, secondary infarction, severe disability (modified Rankin scale score ≥3), and death. RESULTS: Infratentorial CVMs were more prone to intracranial hemorrhage (75% vs. 28.6%; P < 0.001), dizziness (37.5% vs. 10.7%; P = 0.017), and focal neurological deficits (65.6% vs. 25%; P = 0.002) than were supratentorial CVMs. Supratentorial CVMs were more prone to seizure (32.1% vs. 0%; P = 0.001) than were infratentorial CVMs. Multivariate logistic regression revealed that the major risk factors for intracranial hemorrhage in CVMs were infratentorial lesions (P = 0.003) and complicated cavernous angiomas (P = 0.016). Compared with conservative treatment, resection of hematoma or cavernous angiomas with CVM preservation did not increase the risk of poor outcomes (P = 0.646). However, CVM resection significantly increased that risk (odds ratio, 44.0; P = 0.003). CONCLUSIONS: Our results have shown that conservative treatment of CVMs results in a relatively good prognosis. For those complicated by hemorrhage or cavernous angiomas requiring surgical interventions, the integrity of the CVM should be preserved, irrespective of the treatment. In exceptional cases, before CVM resection, the CVM drainage should be comprehensively evaluated.


Asunto(s)
Malformaciones Vasculares del Sistema Nervioso Central/diagnóstico por imagen , Hemorragias Intracraneales/epidemiología , Convulsiones/epidemiología , Adolescente , Adulto , Anciano , Pueblo Asiatico , Malformaciones Vasculares del Sistema Nervioso Central/epidemiología , Malformaciones Vasculares del Sistema Nervioso Central/fisiopatología , Malformaciones Vasculares del Sistema Nervioso Central/terapia , Niño , Preescolar , China/epidemiología , Tratamiento Conservador , Manejo de la Enfermedad , Femenino , Hemangioma Cavernoso del Sistema Nervioso Central/diagnóstico por imagen , Hemangioma Cavernoso del Sistema Nervioso Central/epidemiología , Hemangioma Cavernoso del Sistema Nervioso Central/fisiopatología , Hemangioma Cavernoso del Sistema Nervioso Central/terapia , Humanos , Modelos Logísticos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Análisis Multivariante , Procedimientos Neuroquirúrgicos , Pronóstico , Estudios Retrospectivos , Convulsiones/fisiopatología , Tomografía Computarizada por Rayos X , Adulto Joven
10.
Environ Sci Pollut Res Int ; 23(11): 10808-10817, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26893180

RESUMEN

Only a few studies have been reported on the stability and heavy metal distribution of soil aggregates after soil treatments to reduce the availability of heavy metals. In this study, apatite (22.3 t ha(-1)), lime (4.45 t ha(-1)), and charcoal (66.8 t ha(-1)) were applied to a heavy metal-contaminated soil for 4 years. The stability and heavy metal distribution of soil aggregates were investigated by dry and wet sieving. No significant change in the dry mean weight diameter was observed in any treatments. Compared with the control, three-amendment treatments significantly increased the wet mean weight diameter, but only charcoal treatment significantly increased the wet aggregate stability. The soil treatments increased the content of soil organic carbon, and the fraction 0.25-2 mm contained the highest content of soil organic carbon. Amendments' application slightly increased soil total Cu and Cd, but decreased the concentrations of CaCl2 -extractable Cu and Cd except for the fraction <0.053 mm. The fractions >2 and 0.25-2 mm contained the highest concentrations of CaCl2-extractable Cu and Cd, accounted for about 74.5-86.8 % of CaCl2-extractable Cu and Cd in soil. The results indicated that amendments' application increased the wet soil aggregate stability and decreased the available Cu and Cd. The distribution of available heavy metals in wet soil aggregates was not controlled by soil aggregate stability, but possibly by soil organic carbon.


Asunto(s)
Apatitas/química , Cadmio/química , Compuestos de Calcio/química , Carbón Orgánico/química , Cobre/química , Óxidos/química , Contaminantes del Suelo/química , Suelo/química , Cadmio/análisis , Cloruro de Calcio/química , Cobre/análisis , Contaminación Ambiental , Restauración y Remediación Ambiental , Contaminantes del Suelo/análisis
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