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Gamma-aminobutyric acid (GABA) is an vital neurotransmitter, and the reaction to obtain GABA through biocatalysis requires coenzymes, which are therefore limited in the production of GABA. In this study, polyacrylamide hydrogels doped with chitosan and waste toner were synthesized for glutamate decarboxylase (GAD) and coenzyme co-immobilization to realize the production of GABA and the recovery of coenzymes. Enzymatic properties of immobilized GAD were discussed. The immobilized enzymes have significantly improved pH and temperature tolerance compared to free enzymes. In terms of reusability, after 10 repeated reuses of the immobilized GAD, the residual enzyme activity of immobilized GAD still retains 100% of the initial enzyme activity, and the immobilized coenzyme can also be kept at about 32%, with better stability and reusability. And under the control of no exogenous pH, immobilized GAD showed good performance in producing GABA. Therefore, in many ways, the new composite hydrogel provides another way for the utilization of waste toner and promises the possibility of industrial production of GABA.
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Quitosana , Glutamato Descarboxilase/química , Ácido gama-Aminobutírico , Coenzimas , Fenômenos MagnéticosRESUMO
This review aimed to identify barriers to employee vaccination, motivators for vaccination, and vaccine uptake strategies within the critical infrastructure sectors. We focused on non-healthcare-related sectors, including food and agriculture, manufacturing, and education where employee vaccination is rarely mandated. We conducted a search for literature published from 2012 to 2022 from MEDLINE-PubMed, PsycINFO, and Web of Science Core Collection, which resulted in 22 studies that met the inclusion criteria. We found that 1) barriers to vaccination differ by infectious disease and population; 2) common motivators for vaccination were about protecting self, family, and community; and 3) common uptake strategies for influenza (which accounted for 83% of uptake strategies in reviewed studies) addressed convenience and confidence barriers such as vaccination cost and education. Our review highlights the need for employers, policymakers, and researchers to identify infectious disease and population-specific barriers to vaccination and implement strategies aimed at addressing the identified barriers.
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Vacinas contra Influenza , Influenza Humana , Humanos , Pessoal de Saúde/educação , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , VacinaçãoRESUMO
Since the successful separation of graphene from its bulk counterpart, two-dimensional (2D) layered materials have become the focus of research for their exceptional properties. The layered hexagonal boron nitride (h-BN), for instance, offers good lubricity, electrical insulation, corrosion resistance, and chemical stability. In recent years, the wide-band-gap layered h-BN has been recognized for its broad application prospects in neutron detection and quantum information processing. In addition, it has become very important in the field of 2D crystals and van der Waals heterostructures due to its versatility as a substrate, encapsulation layer, and a tunneling barrier layer for various device applications. However, due to the poor adhesion between h-BN and substrate and its high preparation temperature, it is very difficult to prepare large-area and denseh-BN films. Therefore, the controllable synthesis of h-BN films has been the focus of research in recent years. In this paper, the preparation methods and applications of h-BN films on III-V compounds are systematically summarized, and the prospects are discussed.
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Enzyme immobilization provides ideal operating conditions for enzymes stabilization and sustainable recycling. In this work, as a kind of clay material, montmorillonite (MTL) was chosen for immobilizing the ß-glucosidase extracted from Agrocybe aegirit. The immobilized ß-glucosidase via partly cross-linking enzyme aggregates (pCLEAs) formed by self-catalysis provided biocatalysts with satisfactory thermal and pH stability. Compared to the glutaraldehyde cross-linked, the immobilized ß-glucosidase (ß-G-pCLEAs@MTL) exhibited significantly higher immobilization efficiency (IE) and immobilization yield (IY), which were 80.6% and 76.9%, respectively. The ß-G-pCLEAs@MTL also showed better stability and preferable reusability. And the activity of the ß-G-pCLEAs@MTL remained 85.0% after 5 cycles and 74.7% after 10 cycles. Therefore, the method based on the pre- crosslinking to form pCLEAs and after-immobilization can effectively improve IY and IE. In addition, MTL seems to be a good alternative carrier to immobilize other enzymes for industrial application.
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Bentonita , Enzimas Imobilizadas , Argila , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Glutaral , Concentração de Íons de Hidrogênio , Temperatura , beta-Glucosidase/metabolismoRESUMO
Natural deep eutectic solvents (NADESs) have received considerable attention for green extraction. In this study, ultrasonic-assisted natural deep eutectics were applied for hydrodistillation to extract essential oil from perilla leaves. Compared to hydrodistillation assisted with ultrasound, this novel method effectively raised the yield of perilla leaf EO from 0.21% to 0.69% (choline chloride: malic acid, molar ratio 2:1) and broadened the types of chemical compositions (71 in total), especially aliphatic and aromatic compounds. Stronger antimicrobial and antioxidant activity was confirmed, and phenolics were increased. Additionally, the pH of the final solution was detected. The leaf residues were dried, weighed and analyzed by scanning electron microscopy to show the influence of NADESs' strong extractability. This new extraction method may be applicable in edible natural product extraction and provide a reference for further exploration of NADESs.
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Óleos Voláteis , Perilla , Solventes Eutéticos Profundos , Destilação , Folhas de Planta , Solventes , UltrassomRESUMO
OBJECTIVE: The purpose of the present study was to investigate the relationship between the intrasellar pressure (ISP) and the microvascular structure of pituitary adenomas. METHODS: We retrospectively analyzed the ISP in 66 patients with pituitary adenomas. The corresponding microvascular structure was obtained using immunohistochemistry and analyzed for its correlation with the ISP. RESULTS: The average ISP was 25.89 ± 8.27 mm Hg, and the ISP was not related to the size of the adenoma (Pearson correlation coefficient, 0.103; P = 0.415). The ISPs of adenomas with different Knosp grades were significantly different (P < 0.05). From grade 0 to grade 4, at first, the ISP increased with the Knosp grade and reached the first peak at grade 2. It then decreased at grade 3 and increased again at grade 4, showing a "double-peak" pattern. The minimal diameter and perimeter of the microvessels and the vessel-covered area percentage were positively related to the ISP. When these parameters were compared among the adenomas of different Knosp grades, they also exhibited a "double-peak" pattern. CONCLUSIONS: In the present study, we found that with the increase in pituitary adenoma size and invasion of the surrounding tissues, the ISP of pituitary adenomas showed a "double-peak" pattern. The ISP and certain parameters of the microvascular structure are related, because the microvasculature adaptively changes its structure in response to the changing ISP to ensure a sufficient blood supply to the adenoma. The specific mechanism of this phenomenon requires further study.
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Adenoma/irrigação sanguínea , Adenoma/fisiopatologia , Microcirculação , Neoplasias Hipofisárias/irrigação sanguínea , Neoplasias Hipofisárias/fisiopatologia , Adulto , Idoso , Capilares/patologia , Estudos de Coortes , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , Invasividade Neoplásica , Pressão , Estudos RetrospectivosRESUMO
OBJECTIVE: In this study, the sellar floor morphology of patients with pituitary adenoma is analyzed and a simple yet reliable method is identified to determine the location of bone window opening. METHODS: Clinical information of 144 consecutively admitted patients was retrospectively analyzed. Enhanced magnetic resonance imaging of the midsagittal plane was selected as the reference for classifying the sellar floor. Intraoperative tumor location, extent of tumor resection, and follow-up results were analyzed for different types of sellar floor. The tuberculum sellae, lowest point of the sphenoid sinus, and the lowest point of the sellar floor and 3 lines related to them were used to classify the sellar floor. This is referred to as the "three points and three lines" method. RESULTS: Based on its location in the sphenoid sinus, the sellar floor can be classified into 4 types: 12 patients (8.3%) with high sellar, 70 (48.6%) with medium sellar, 30 (20.8%) with low sellar, and 32 (22.8%) with steep sellar. The maximum tumor diameter, maximum sellar floor diameter, and the intercarotid distance were all significantly different among patients with different types of sellar floor (P < 0.001). For all patients, quick intraoperative location of the sellar floor opening was achieved. A total of 104 patients (72.2%) had total tumor resection, 28 (19.40%) had subtotal tumor resection, and 4 (2.8%) had partial tumor resection. Twenty patients (13.9%) experienced cerebrospinal fluid leak, and there was no significant difference in cerebrospinal fluid leak rate among groups. CONCLUSIONS: Presurgical classification and location of the sellar floor are critical for understanding and assessing the transsphenoidal approach. Different types of sellar floor appeared in the surgery with different morphologic features. The three points and three lines method helps the surgeon to predetermine the location of the sellar floor opening and to shorten surgical time.
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Adenoma/cirurgia , Microcirurgia/métodos , Procedimentos Neurocirúrgicos/métodos , Neoplasias Hipofisárias/cirurgia , Sela Túrcica/diagnóstico por imagem , Sela Túrcica/cirurgia , Seio Esfenoidal/cirurgia , Adenoma/diagnóstico por imagem , Adulto , Idoso , Pontos de Referência Anatômicos , Vazamento de Líquido Cefalorraquidiano/epidemiologia , Vazamento de Líquido Cefalorraquidiano/etiologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Neoplasias Hipofisárias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Estudos RetrospectivosRESUMO
BACKGROUND: Breast cancer (BC) is a common cancer in women worldwide. Emerging evidence has indicated that circular RNA hsa-circ_0007255 (circ_0007255) is a prognostic mediator in BC progression. However, the functional role of circ_0007255 needs to be determined. METHODS: The expression of circ_0007255, microRNA (miR)-335-5p, and SIX Homeobox 2 (SIX2) was evaluated using quantitative real-time polymerase chain reaction (qRT-PCR) or western blot assay. Actinomycin D and RNase R treatment was performed to analyze the stability of circ_0007255. Additionally, Seahorse extracellular flux, colony formation and transwell analyses were carried out to detect oxygen consumption ratio (OCR), colony formation and cell mobility, respectively. The interaction between miR-335-5p and circ_0007255 or SIX2 was confirmed via dual-luciferase reporter assay. A xenograft tumor model was established to explore the role of circ_0007255 in vivo. RESULTS: Circ_0007255 and SIX2 were overexpressed, but miR-335-5p was diminished in BC tissues and cells. Circ_0007255 absence inhibited oxygen consumption, colony formation, cell migration and invasion, and these effects were particularly abrogated via miR-335-5p upregulation in BC cells. Moreover, SIX2 deficiency eliminated the promotion effects of miR-335-5p inhibitor on oxygen consumption, colony formation, and cell mobility in BC cells. Importantly, circ_0007255 inhibited tumor growth in vivo. Mechanically, circ_0007255 was a sponge of miR-335-5p to regulate SIX2 expression in BC progression. CONCLUSION: Circ_0007255 functioned as a novel oncogene in the progression of BC by regulating miR-335-5p/SIX2 axis, and might be a promising biomarker for BC treatment. KEY POINTS: Significant findings of the study: Levels of circ_0007255 and SIX2 were upregulated, but miR-335-5p was diminished in BC tissues and cells. Circ_0007255 was an oncogene in BC development and exerted its function via miR-335-5p/SIX2 axis in BC. Tumor growth was reduced by circ_0007255 absence. WHAT THIS STUDY ADDS: Circ_0007255 functioned as a novel oncogene in the progression of BC by regulating miR-335-5p/SIX2 axis, and might be a promising biomarker for BC treatment.
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Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Proteínas de Homeodomínio/metabolismo , MicroRNAs/genética , Proteínas do Tecido Nervoso/metabolismo , RNA Circular/genética , Animais , Apoptose , Biomarcadores Tumorais/genética , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Proliferação de Células , Feminino , Proteínas de Homeodomínio/genética , Humanos , Camundongos , Camundongos Nus , Proteínas do Tecido Nervoso/genética , Prognóstico , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Noninvasive imaging plays a pivotal role in assessing the brain structural and functional changes in presurgical mesial temporal lobe epilepsy (MTLE) patients. Our goal was to study the relationship between the changes of cerebral white matter (WM) and cognitive functions in MTLE patients.Voxel-based morphometry (VBM) and tract-based spatial statistics (TBSS) MRI were performed on 24 right-handed MTLE patients (12 with left MTLE and 12 with right MTLE) and 12 matching healthy controls. Gray matter (GM), WM, and whole brain (WB) volumes were measured with VBM while fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were measured with TBSS. All patients and controls also underwent Montreal Cognitive Assessment (MoCA) before MRI.WM volume and the ratio of WM volume versus WB volume were significantly lower in MTLE patients compared with controls. WM volume in MTLE patients had a positive correlation with MoCA score (râ=â0.71, Pâ<â.001) and a negative correlation with the duration of epilepsy (râ=â-0.693, Pâ<â.001). Volumetric differences were mainly located in the corpus callosum, uncinate fasciculus, inferior longitudinal fasciculus, and superior longitudinal fasciculus. FA of both left MTLE and right MTLE groups was significantly decreased, while MD, AD, and RD were significantly increased. Most left MTLE patients showed bilateral WM fiber tract changes versus ipsilateral changes for right MTLE patients.Changes in DTI parameters and WM volume were found in MTLE patients and more ipsilateral changes were seen with right-sided MTLE. Cognitive changes of MTLE patients were found to be correlated with the changes in WM structure. These findings not only provide useful information for lateralization of the seizure focus but can also be used to explain functional connectivity disorders which may be an important physiological basis for cognitive changes in patients with MTLE.
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Encéfalo/patologia , Disfunção Cognitiva/patologia , Epilepsia do Lobo Temporal/diagnóstico por imagem , Substância Cinzenta/patologia , Imageamento por Ressonância Magnética/métodos , Substância Branca/patologia , Adulto , Anisotropia , Encéfalo/anatomia & histologia , Encéfalo/diagnóstico por imagem , Líquido Cefalorraquidiano/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Corpo Caloso/anatomia & histologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/patologia , Imagem de Tensor de Difusão/métodos , Epilepsia do Lobo Temporal/patologia , Feminino , Substância Cinzenta/anatomia & histologia , Substância Cinzenta/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/tendências , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiopatologia , Convulsões/fisiopatologia , Substância Branca/anatomia & histologia , Substância Branca/diagnóstico por imagemRESUMO
The quorum sensing (QS) inhibitory activity of hordenine from sprouting barley against foodborne pathogen Pseudomonas aeruginosa was evaluated for the first time here. At concentrations ranging from 0.5 to 1.0 mg mL-1, hordenine inhibited the levels of acyl-homoserine lactones. The enhanced susceptibility of hordenine with netilmicin on P. aeruginosa PAO1 biofilm formation as well as their efficiency in disrupting preformed biofilms was also evaluated using scanning electron microscopy and confocal laser scanning microscopy (CLSM). Hordenine treatment inhibited the production of QS-related extracellular virulence factors of P. aeruginosa PAO1. Additionally, quantitative real-time polymerase chain reaction analysis demonstrated that the expressions of QS-related genes, lasI, lasR, rhlI, and rhlR, were significantly suppressed. Our results indicated that hordenine can serve as a competitive inhibitor for signaling molecules and act as a novel QS-based agent to defend against foodborne pathogens.
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Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Hordeum/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Tiramina/análogos & derivados , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/fisiologia , Tiramina/farmacologiaRESUMO
PURPOSE: Traumatic brain injury (TBI) can result in significant social dysfunction, which is represented by impairment to social-cognitive abilities (i.e. social cognition, social attention/executive function and communication). This study is aimed to explore brain networks mediating the social dysfunction after TBI and its underlying mechanisms. METHODS: We performed a quantitative meta-analysis using the activation likelihood estimation (ALE) approach on functional magnetic resonance imaging (fMRI) studies of social-cognitive abilities following TBI. Sixteen studies fulfilled the inclusion criteria resulting in a total of 190 patients with TBI and 206 controls enrolled in the ALE meta-analysis. RESULTS: The temporoparietal junction (TPJ) and the medial prefrontal cortex (mPFC) were the specific regions that social cognition predominantly engaged. The cingulate gyrus, frontal gyrus and inferior parietal lobule were the main regions related to social attention/executive functions. Communication dysfunction, especially related to language deficits, was found to show greater activation of the temporal gyrus and fusiform gyrus in TBI. CONCLUSION: The current ALE meta-analytic findings provide evidence that patients have significant social-cognitive disabilities following TBI. The relatively limited pool of literature and the varied fMRI results from published studies indicate that social-cognitive abilities following TBI is an area that would greatly benefit from further investigation.
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Lesões Encefálicas Traumáticas/psicologia , Encéfalo/diagnóstico por imagem , Transtornos Cognitivos/psicologia , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Transtornos Cognitivos/diagnóstico por imagem , Transtornos Cognitivos/etiologia , Neuroimagem Funcional , Humanos , Imageamento por Ressonância MagnéticaRESUMO
OBJECTIVES: Type 2 diabetes mellitus (T2DM) increases the risk of brain atrophy and dementia. We aimed to elucidate deep grey matter (GM) structural abnormalities and their relationships with T2DM cognitive deficits by combining region of interest (ROI)-based volumetry, voxel-based morphometry (VBM) and shape analysis. METHODS: We recruited 23 T2DM patients and 24 age-matched healthy controls to undergo T1-weighted structural MRI scanning. Images were analysed using the three aforementioned methods to obtain deep GM structural shapes and volumes. Biochemical and cognitive assessments were made and were correlated with the resulting metrics. RESULTS: Shape analysis revealed that T2DM is associated with focal atrophy in the bilateral caudate head and dorso-medial part of the thalamus. ROI-based volumetry only detected thalamic volume reduction in T2DM when compared to the controls. No significant between-group differences were found by VBM. Furthermore, a worse performance of cognitive processing speed correlated with more severe GM atrophy in the bilateral dorso-medial part of the thalamus. Also, the GM volume in the bilateral dorso-medial part of the thalamus changed negatively with HbA1c. CONCLUSIONS: Shape analysis is sensitive in identifying T2DM deep GM structural abnormalities and their relationships with cognitive impairments, which may greatly assist in clarifying the neural substrate of T2DM cognitive dysfunction. KEY POINTS: ⢠Type 2 diabetes mellitus is accompanied with brain atrophy and cognitive dysfunction ⢠Deep grey matter structures are essential for multiple cognitive processes ⢠Shape analysis revealed local atrophy in the dorso-medial thalamus and caudatum in patients ⢠Dorso-medial thalamic atrophy correlated to cognitive processing speed slowing and high HbA1c. ⢠Shape analysis has advantages in unraveling neural substrates of diabetic cognitive deficits.
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Encefalopatias/patologia , Transtornos Cognitivos/patologia , Diabetes Mellitus Tipo 2/patologia , Substância Cinzenta/patologia , Adulto , Idoso , Atrofia/patologia , Estudos de Casos e Controles , Demência/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Tálamo/patologiaRESUMO
PURPOSE: To explore the regional spontaneous neural activity and functional connectivity alterations of adjustment disorder (AD) in new recruits with in vivo resting-state functional MR (rs-fMRI). MATERIALS AND METHODS: Resting-state fMRI was performed in 31 recruits with AD and in 31 control recruits. Regional homogeneity (ReHo) was used to detect the regional synchronizing features of neuronal activations. Correlative analysis was performed to investigate the relationship between the Symptom Check List-90 (SCL-90) score and ReHo in regions with significant group differences. Regions with significant correlation were then defined as regions of interest (ROIs), and seed-ROI based whole-brain functional connectivity was performed. RESULTS: Compared with the controls, patients with AD had significantly lower ReHo in the left posterior cerebellar lobe, bilateral medial orbitofrontal cortex, bilateral caudate and left middle temporal gyrus, whereas regions with enhanced ReHo were confined to bilateral posterior cingulate gyrus/precuneus. Only the left posterior cerebellar lobe showed significant correlation between ReHo and the SCL-90 score, and was defined as the seed ROI. Decreased functional connectivity was found between the ROI and bilateral supplementary motor area. CONCLUSION: This study reveals abnormalities in recruits with AD in baseline brain function activities, which could further improve our understanding of the neural substrates of cognitive impairment in AD.
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Transtornos de Adaptação/diagnóstico por imagem , Transtornos de Adaptação/fisiopatologia , Militares/psicologia , Transtornos de Adaptação/psicologia , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/fisiopatologia , Estudos de Casos e Controles , Cerebelo/diagnóstico por imagem , Cerebelo/fisiopatologia , Lateralidade Funcional , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Vias Neurais/diagnóstico por imagem , Vias Neurais/fisiopatologia , Adulto JovemRESUMO
The aim of the present study was to identify monitoring and prevention measures as well as predictive factors for early detection of renal toxicity associated with long-term administration of adefovir dipivoxil in order to avoid progression to Fanconi syndrome. Clinical data of 28 patients with Fanconi syndrome caused by long-term administration of adefovir dipivoxil for the treatment of chronic hepatitis B virus (HBV) infection were collected pre-and post-administration for analysis. Patients presented with fatigue, progressive systemic pain in multiple bones and joints, as well as difficulty in walking and pathological fractures in a number of severe cases. Laboratory examinations revealed hypophosphatemia, elevated serum cystatin C (Cys-C), elevated serum creatinine (SCr), reduced glomerular filtration rate (GFR), positive urinary protein, erythrocytes and glucose, as well as osteoporosis. In consequence, adefovir dipivoxil administration was stopped, and patients received concentrated divitamins, sodium phosphate syrup and calcitriol. Symptoms and abnormalities in laboratory examinations were significantly improved in all patients after 2-6 months. Therefore, serum phosphate, SCr, routine urine parameters, Cys-C and GFR should be monitored regularly in chronic HBV patients treated with adefovir dipivoxil. The following factors were identified as predictive of kidney damage and Fanconi syndrome: Age ≥40 years, living in rural areas, previous renal toxicity, estimated GFR (eGFR) <90 ml/min/1.73 m2, hypertension, diabetes, cirrhosis and duration of adefovir dipivoxil treatment exceeding 24 months. The present results indicate that timely termination of adefovir dipivoxil treatment and replacement with other antiviral agents is critical once renal impairment appears, and that it is necessary to change to other antiviral agents and prolong the interval of administration according to the eGFR level.
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BACKGROUND: Structural and functional networks can be reorganized to adjust to environmental pressures and physiologic changes in the adult brain, but such processes remain unclear in prolonged adaptation to high-altitude (HA) hypoxia. This study aimed to characterize the interhemispheric functionally and structurally coupled modifications in the brains of adult HA immigrants. METHODS: We performed resting-state functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) in 16 adults who had immigrated to the Qinghai-Tibet Plateau (2300-4400 m) for 2 years and in 16 age-matched sea-level (SL) controls. A recently validated approach of voxel-mirrored homotopic connectivity (VMHC) was employed to examine the interhemispheric resting-state functional connectivity. Areas showing changed VMHC in HA immigrants were selected as regions of interest for follow-up DTI tractography analysis. The fiber parameters of fractional anisotropy and fiber length were obtained. Cognitive and physiological assessments were made and correlated with the resulting image metrics. RESULTS: Compared with SL controls, VMHC in the bilateral visual cortex was significantly increased in HA immigrants. The mean VMHC value extracted within the visual cortex was positively correlated with hemoglobin concentration. Moreover, the path length of the commissural fibers connecting homotopic visual areas was increased in HA immigrants, covarying positively with VMHC. CONCLUSIONS: These observations are the first to demonstrate interhemispheric functional and structural connectivity resilience in the adult brain after prolonged HA acclimatization independent of inherited and developmental effects, and the coupled modifications in the bilateral visual cortex indicate important neural compensatory mechanisms underlying visual dysfunction in physiologically well-acclimatized HA immigrants. The study of human central adaptation to extreme environments promotes the understanding of our brain's capacity for survival.
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An area of rapid advancement in abdominal MRI is diffusion-weighted imaging (DWI). By measuring diffusion properties of water molecules, DWI is capable of non-invasively probing tissue properties and physiology at cellular and macromolecular level. The integration of DWI as part of abdominal MRI exam allows better lesion characterization and therefore more accurate initial diagnosis and treatment monitoring. One of the most technical challenging, but also most useful abdominal DWI applications is in liver and therefore requires special attention and careful optimization. In this article, the latest technical developments of DWI and its liver applications are reviewed with the explanations of the technical principles, recommendations of the imaging parameters, and examples of clinical applications. More advanced DWI techniques, including Intra-Voxel Incoherent Motion (IVIM) diffusion imaging, anomalous diffusion imaging, and Diffusion Kurtosis Imaging (DKI) are discussed.
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Imagem de Difusão por Ressonância Magnética/tendências , Hepatopatias/diagnóstico , Humanos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodosRESUMO
OBJECT The objectives of this study were to describe a novel minimal-access subtemporal approach for selective resection of the amygdala and hippocampus in patients with medically refractory mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis, and to analyze the related outcomes. METHODS The authors analyzed data from all cases involving patients with unilateral MTLE due to hippocampal sclerosis who were treated with selective amygdalohippocampectomy via the posterior subtemporal approach through a relatively small craniotomy, without a neuronavigation system, at their institution during the period from September 2010 to September 2012. Data were obtained on baseline characteristics, preoperative evaluations of unilateral mesial temporal sclerosis, surgical complications, and Engel class seizure outcomes. All patients underwent memory testing, IQ testing, and language testing. RESULTS The mean duration of follow-up was 33.6 months (range 24-48 months). There were no deaths and no cases of significant postoperative morbidity. One patient had a mild complication. At 2-year follow-up, 19 patients were seizure free (Engel Class I outcome). Verbal memory scores obtained at 3 months and at 2 years after surgery were significantly lower than preoperative scores for patients who underwent surgery on the left side of the brain (p < 0.05). Pictorial memory scores were higher following surgery compared with before surgery regardless of whether patients underwent left- or right-sided brain surgery. There was also improvement in performance IQ and total IQ following surgery in both groups. For patients who underwent right-sided brain surgery, verbal comprehension and semantic fluency testing scores were significantly higher at both 3 months and 2 years after surgery than before surgery. For patients who underwent left-sided brain surgery, scores on all language tests were significantly lower at 3 months after surgery than before surgery. Verbal comprehension testing scores returned to the preoperative level at 2 years after surgery. CONCLUSIONS The posterior subtemporal approach through a relatively small craniotomy allows adequate exposure and safe resection of mesial temporal structures and effectively reduces medically intractable MTLE. It preserves IQ but may have a detrimental effect on verbal memory and language ability.
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Tonsila do Cerebelo/cirurgia , Lobectomia Temporal Anterior/métodos , Craniotomia/métodos , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/cirurgia , Adolescente , Adulto , Epilepsia do Lobo Temporal/psicologia , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
Surgical approaches for medically refractory mesial temporal lobe epilepsy (MTLE) that previously have been reported include anterior temporal lobectomy (ATL), transcortical selective amygdalohippocampectomy, transsylvian amygdalohippocampectomy, and subtemporal amygdalohippocampectomy. Each approach has its advantages and potential pitfalls. The purpose of this report is to describe our technique of keyhole corticoamygdalohippocampectomy for patients with MTLE due to hippocampal sclerosis. Operations were performed through a 6-cm vertical linear incision and a low 2.5-cm keyhole craniotomy at the anterior squamous temporal bone. Resection of the anterior-most portions of the middle and inferior temporal gyri provided a cylinder-like corridor to the mesial temporal lobe. Identification of the temporal horn through a basal approach was followed by resection of the amygdala, uncus, and hippocampus-parahippocampal gyrus. This 9-year series included 683 patients with a minimum follow-up duration of 2 years. Surgery times were short (range, 1 h 35 min to 2 h 30 min). Only a small percentage of patients had complications (1.76%), and the rate of Engel Class I seizure-free outcome was 87%. No overt speech problems or visual field deficits were identified. Compared with the most popular conventional trans-middle temporal gyrus approach, this technique can make the operation easier, safer, and less traumatic to functional lateral neocortex.
Assuntos
Tonsila do Cerebelo/cirurgia , Córtex Cerebral/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Hipocampo/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Procedimentos Neurocirúrgicos/métodos , Ventrículos Cerebrais/cirurgia , Craniotomia , Seguimentos , Hipocampo/patologia , Humanos , Testes de Inteligência , Imageamento por Ressonância Magnética , Esclerose , Osso Temporal/cirurgia , Resultado do Tratamento , Campos VisuaisRESUMO
OBJECTIVE: The purpose of this study was to investigate the application of histogram analysis of apparent diffusion coefficient (ADC) in characterizing pathologic features of cervical cancer and benign cervical lesions. SUBJECTS AND METHODS: This prospective study was approved by the institutional review board, and written informed consent was obtained. Seventy-three patients with cervical cancer (33-69 years old; 35 patients with International Federation of Gynecology and Obstetrics stage IB cervical cancer) and 38 patients (38-61 years old) with normal cervix or cervical benign lesions (control group) were enrolled. All patients underwent 3-T diffusion-weighted imaging (DWI) with b values of 0 and 800 s/mm(2). ADC values of the entire tumor in the patient group and the whole cervix volume in the control group were assessed. Mean ADC, median ADC, 25th and 75th percentiles of ADC, skewness, and kurtosis were calculated. Histogram parameters were compared between different pathologic features, as well as between stage IB cervical cancer and control groups. RESULTS: Mean ADC, median ADC, and 25th percentile of ADC were significantly higher for adenocarcinoma (p = 0.021, 0.006, and 0.004, respectively), and skewness was significantly higher for squamous cell carcinoma (p = 0.011). Median ADC was statistically significantly higher for well or moderately differentiated tumors (p = 0.044), and skewness was statistically significantly higher for poorly differentiated tumors (p = 0.004). No statistically significant difference of ADC histogram was observed between lymphovascular space invasion subgroups. All histogram parameters differed significantly between stage IB cervical cancer and control groups (p < 0.05). CONCLUSION: Distribution of ADCs characterized by histogram analysis may help to distinguish early-stage cervical cancer from normal cervix or cervical benign lesions and may be useful for evaluating the different pathologic features of cervical cancer.