Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 46
Filtrar
Mais filtros

Base de dados
Tipo de documento
Intervalo de ano de publicação
1.
Prep Biochem Biotechnol ; 54(1): 103-114, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37184437

RESUMO

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.


Assuntos
Quitosana , Glutamato Descarboxilase/química , Ácido gama-Aminobutírico , Coenzimas , Fenômenos Magnéticos
2.
Prep Biochem Biotechnol ; 52(9): 1035-1043, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35015605

RESUMO

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.


Assuntos
Bentonita , Enzimas Imobilizadas , Argila , Estabilidade Enzimática , Enzimas Imobilizadas/metabolismo , Glutaral , Concentração de Íons de Hidrogênio , Temperatura , beta-Glucosidase/metabolismo
3.
Eur Radiol ; 27(10): 4247-4256, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28374074

RESUMO

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.


Assuntos
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/patologia
4.
Brain Inj ; 31(10): 1331-1339, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28627941

RESUMO

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.


Assuntos
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 Magnética
5.
Neurosurg Rev ; 39(1): 99-108; discussion 108, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26277790

RESUMO

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 Visuais
6.
AJR Am J Roentgenol ; 204(5): 1125-31, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25905952

RESUMO

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.


Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Pessoa de Meia-Idade , Estudos Prospectivos
7.
Abdom Imaging ; 40(1): 95-101, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25056714

RESUMO

OBJECTIVE: To determine if transit time for excretion of gadoxetate into major bile ducts and duodenum correlates with clinical models of hepatocellular function. METHODS: This retrospective research was approved by the Institutional Review Board with waiver of informed consent. Search of the radiology database from January 1, 2013 to March 4, 2014 revealed 84 patients with chronic liver disease (65 males, mean age 47 years). Eighteen control subjects with no known liver disease or risk factors were also enrolled for analysis (9 males, mean age 43 years). MRI was performed with hepatobiliary phases at 10, 15, 20, and 25 min after injection of 0.025 mmol/kg of gadoxetate (Primovist, Bayer HealthCare, Shanghai, China). The time of excreted contrast appearing in the biliary tree and in the duodenum was recorded. Linear trend analysis was performed to determine the relationship between excretion time and hepatic function. RESULTS: The patient cohort was stratified by Child-Pugh classification (A, B, and C with n = 53, 27, and 4, respectively). Arrival of gadoxetate in the gall bladder at 10-min hepatobiliary phase was seen in 87% of control group and 45% of Child-Pugh A group (p = 0.02). There was no difference between these groups for later hepatobiliary phases. The arrival of biliary contrast in the right hepatic duct, common bile duct, and gall bladder were significantly earlier in the Child-Pugh A group compared to the Child-Pugh B/C group at all hepatobiliary phases after 10 min (p < 0.05). Linear trend analysis showed that biliary transit times were significantly delayed with worsening liver function (p = 0.01). There was no difference in entry time of gadoxetate into the duodenum between the normal, Child-Pugh A, and Child-Pugh B/C groups. CONCLUSIONS: The transit time for gadoxetate to appear in extrahepatic duct is a reasonable indicator of liver function, and may be included in radiology reports. The appearance in the duodenum, however, may depend on factors other than liver function, such as the physiology of the gallbladder and sphincter of Oddi.


Assuntos
Meios de Contraste/farmacocinética , Gadolínio DTPA/farmacocinética , Hepatócitos/patologia , Fígado/fisiopatologia , Imageamento por Ressonância Magnética , Adolescente , Adulto , Feminino , Humanos , Testes de Função Hepática , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
8.
Acta Neurochir (Wien) ; 157(1): 63-75, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25278241

RESUMO

PURPOSE: We reported our experience in the surgical treatment of a relatively large cohort of patients with occipital lobe epilepsy (OLE). We also carried out a systematic review of the literature on OLE. METHODS: Thirty-five consecutive patients who underwent occipital resection for epilepsy were included. Diagnoses were made following presurgical evaluations, including magnetic resonance imaging (MRI), fluorodeoxyglucose-positron emission tomography (FDG-PET), scalp video-electroencephalogram (EEG) monitoring, and intracranial EEG monitoring. At last follow-up, seizure outcome was classified using the Engel classification scheme. RESULTS: Twenty-five of 35 patients experienced/had experienced ≥1 type of aura before the seizure. Invasive recordings were used to define the epileptogenic area in 30 of 35 patients (85.7 %). All patients underwent occipital lesionectomies or topectomies. Histopathology revealed: cortical dysplasias, gliosis, dysembryoplastic neuroepithelial tumor, ganglioglioma, and tuberous sclerosis. After a mean follow-up of 44 months, 25 patients (71.4 %) were seizure free (Engel class I), 3 (8.6 %) rarely had seizures (Engel class II), 5 (14.3 %) improved more than 75 % (Engel class III), and 2 (5.7 %) had no significant improvement (Engel class IV). Preoperatively, 12 of 33 patients (36.4 %) had visual field deficits. Postoperatively, 25 patients (75.8 %) had new or aggravated visual field deficits. CONCLUSIONS: The management of OLE has been aided greatly by the availability of high-resolution diagnosis. Postoperative visual field deficits occur in a significant proportion of patients. Comprehensive intracranial EEG coverage of all occipital surfaces helps to define the epileptogenic area and preserve visual function, especially in cases of focal cortical dysplasia undetectable by MRI.


Assuntos
Epilepsias Parciais/cirurgia , Psicocirurgia , Adolescente , Adulto , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/cirurgia , Criança , Pré-Escolar , Eletroencefalografia , Epilepsias Parciais/diagnóstico , Epilepsias Parciais/etiologia , Feminino , Seguimentos , Ganglioglioma/complicações , Ganglioglioma/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/cirurgia , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Resultado do Tratamento
9.
Epilepsy Behav ; 36: 47-52, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24857808

RESUMO

We report on the efficacy and safety of extended, one-stage anterior callosal section that spares the splenium, which is performed in a large series of pediatric patients with drop attacks. Twenty-nine pediatric patients with drop attacks were studied (19 males and 10 females; mean age: 9.9 years). As presurgical factors, the age at surgery, age at seizure onset, age at drop attack onset, sex, hemiparesis, severe mental retardation, electroencephalograph abnormalities, magnetic resonance imaging abnormalities, and (18)fluorodeoxyglucose positron emission tomography abnormalities were analyzed. All patients had multiple seizure types, including drop attacks, atypical absence seizures, complex partial seizures, tonic seizures, and generalized tonic-clonic seizures. All patients were developmentally impaired and had electroencephalograph results showing marked secondary bilateral synchrony. All patients received an extended, one-stage callosal section, leaving only the splenium intact. The mean follow-up time was 5.2 years. Seizure outcome (cessation of seizures or ≥ 90% seizure reduction) was achieved in 79.3% of patients with drop attacks. The families assessed the overall daily function as improved in 62.1% of the patients, unchanged in 24.1%, and worse in 13.8%. Family satisfaction with callosotomy was achieved in 82.8% of the patients. The majority of the patients had some degree of a transient acute postoperative disconnection syndrome that disappeared within 3 weeks. Postoperatively, patients showed a consistent increase in attention levels. We conclude that extended callosal sectioning that leaves the splenium intact should be considered a good palliative surgical option for pediatric patients with drop attacks and that diminishment of epileptic discharge synchrony is a good prognostic sign following callosotomy. We also found that the postoperative increase in attention levels was as useful as seizure control in improving the quality of life of these patients.


Assuntos
Corpo Caloso/cirurgia , Procedimentos Neurocirúrgicos , Síncope/cirurgia , Resultado do Tratamento , Adolescente , Criança , Pré-Escolar , Cognição/fisiologia , Eletroencefalografia , Feminino , Fluordesoxiglucose F18 , Humanos , Estudos Longitudinais , Masculino , Pediatria , Tomografia por Emissão de Pósitrons , Estudos Retrospectivos , Síncope/diagnóstico por imagem , Tomógrafos Computadorizados
10.
Epilepsy Behav ; 41: 91-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25461196

RESUMO

This study compared the long-term efficacy of anterior temporal lobectomy (ATL) for the treatment of medically refractory temporal lobe epilepsy (TLE) in patients who presented with ipsilateral temporal PET hypometabolism and nonlesional magnetic resonance imaging (PET+/MRI-) with that in patients who had mesial temporal sclerosis (MTS) on MRI. We described the electroclinical, MRI, PET, and pathological characteristics and seizure outcome of 28 PET+/MRI--patients without discordant ictal and interictal electroencephalography (EEG) who underwent ATL (2004-2007) for medically refractory partial epilepsy while avoiding intracranial monitoring. The primary outcome was the percentages of Engel Class I outcomes at 2 and 5 years of PET+/MRI--patients compared with those of patients with MTS on MRI; neuropsychological testing was used as the secondary outcome. At 2-year follow-up, 21 (75%) patients in the PET+/MRI--group were in Engel Class I compared with 66 (75.9%) patients with MTS, and at 5-year follow-up, 20 (71.4%) patients in the PET+/MRI--group were in Engel Class I compared with 64 (73.6%) patients in the group with MTS. There were no significant differences between the groups at either time period. We concluded that normal MRI results should not preclude presurgical evaluations in patients with medically refractory TLE, as favorable long-term postoperative seizure outcomes are possible, especially in patients with unilateral anterior interictal epileptiform discharges and ipsilateral temporal PET hypometabolism.


Assuntos
Lobectomia Temporal Anterior , Epilepsia do Lobo Temporal , Imageamento por Ressonância Magnética , Avaliação de Resultados em Cuidados de Saúde , Tomografia por Emissão de Pósitrons , Convulsões/cirurgia , Adulto , Eletroencefalografia , Epilepsia do Lobo Temporal/metabolismo , Epilepsia do Lobo Temporal/patologia , Epilepsia do Lobo Temporal/fisiopatologia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Humanos , Masculino , Recidiva , Convulsões/fisiopatologia , Fatores de Tempo , Resultado do Tratamento
11.
Epileptic Disord ; 16(3): 296-304, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25179817

RESUMO

AIM: To assess the surgical outcomes of temporo-parieto-occipital (TPO) and parieto-occipital (PO) disconnection surgery for children with intractable posterior quadrantic epilepsy and a unilateral posterior quadrant lesion based on MRI and functional imaging abnormality in the TPO region on one side. METHODS: A retrospective review of data of 12 children who underwent TPO or PO disconnective surgery was carried out from September 2009 to September 2012. Three-dimensional surface reconstructions of MRI scans and intraoperative electrophysiological monitoring were used during surgery. Drugs were not discontinued after surgery in any patient. RESULTS: The affected hemisphere was the left in seven patients and the right in five patients. The mean ages at seizure onset and at surgery were four years and 12.3 years, respectively. At the time of surgery, 3 children had atonic seizures, 4 had symptomatic epilepsy with focal seizures and alteration of conscioussness, 4 had secondarily generalised seizures, and 1 child had spasms and tonic seizures. All patients had developmental delay. A pure TPO disconnection was performed in 11 patients and a PO disconnection was performed in the remaining patient. On pathological examination, 3 patients were shown to have focal cortical dysplasia (FCD) Ib, 2 with FCD IIa, 5 with FCD IIb, 1 with gliosis, and 1 with gliosis plus FCD IIa. Following surgery, 2 patients had oedema; 1 required another operation to resect the occipital lobe. At a mean follow-up of 34.5 months, 9 patients (75%) were classified as Engel class I, 2 as Engel Class II, and 1 as Engel class III. All 12 children had contralateral hemianopia postoperatively and improvement in median IQ (p=0.04) was reported three months postoperatively. CONCLUSIONS: With respect to the limits of a retrospective and relatively small sample size series TPO and PO disconnection are safe and effective motor-sparing epilepsy surgical procedures in selected patients with the epileptiform zone located in the posterior quadrant on one side.


Assuntos
Encéfalo/cirurgia , Epilepsia/cirurgia , Gliose/cirurgia , Malformações do Desenvolvimento Cortical/cirurgia , Psicocirurgia/métodos , Adolescente , Encéfalo/patologia , Criança , Pré-Escolar , Epilepsia/complicações , Epilepsia/patologia , Feminino , Gliose/complicações , Gliose/patologia , Humanos , Masculino , Malformações do Desenvolvimento Cortical/complicações , Malformações do Desenvolvimento Cortical/patologia , Estudos Retrospectivos , Resultado do Tratamento
12.
Eur Radiol ; 23(4): 1050-8, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23179520

RESUMO

OBJECTIVES: To evaluate the potential value of apparent diffusion coefficient (ADC) measurement in the assessment of cervical cancer. METHODS: One hundred twelve patients with cervical cancer and 67 control subjects underwent diffusion-weighted imaging (DWI) in addition to routine MR imaging at 3.0-T MRI before therapy. All ADCs were calculated from b = 0, 600 s/mm(2) and b = 0, 1,000 s/mm(2). RESULTS: The ADCs of cervical cancer were significantly lower than those of normal cervix for both ADC maps. There was a statistically significant difference between the ADCs of well-/moderately differentiated (G1/2) tumours and poorly differentiated (G3) tumours, between the ADCs of squamous cell carcinoma and adenocarcinoma, between the pretherapy ADCs of tumour recurrence or metastasis and tumour free patients after radical hysterectomy for both ADC maps. There was no significant difference among the ADCs of cervical cancer when divided by other features (FIGO, lymph node status, tumour size and age groups) for both ADC maps. CONCLUSION: ADC values were reliable for differentiating cervical cancer from normal cervix with high diagnostic accuracy. The ADCs can be used to indicate the degree and histological type of cervical cancer, although there is some overlap. G3 tumours and lower ADCs may indicate poor prognosis. The diagnostic accuracy was equal for both ADC maps.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
13.
J Comput Assist Tomogr ; 37(6): 989-94, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24270123

RESUMO

OBJECTIVE: The objective of this study was to compare the diagnostic performance of diffusion-weighted (DW) imaging with that of dynamic contrast-enhanced (DCE) imaging in the evaluation of tumor extent in patients with stage IB cervical cancer. METHODS: This retrospective study was approved by the institutional review board. Between June 2010 and March 2012, 46 consecutive patients with FIGO (International Federation of Gynecology and Obstetrics) stage IB who underwent preoperative DCE, DW (b = 0 and 800 s/mm), and T1- and T2-weighted imaging were included in this study. Two radiologists independently evaluated the extent of cervical cancer and made a diagnosis of tumor stage according to the revised FIGO staging system. The staging accuracy by DCE and DW for readers 1 and 2 was compared with the McNemar test, and κ statistics were used for reader agreement. RESULTS: No statistical difference between the diagnostic performance of staging with DCE and with DW was observed in reader 1 (P = 1.000) or in reader 2 (P = 0.109). Interobserver agreement between the 2 readers for staging was both substantial with DCE (κ = 0.750, P < 0.001) and with DW (κ = 0.683, P < 0.001). CONCLUSIONS: The diagnostic performance of DW in distinguishing the subdivision of stage IB cervical cancer was not statistically different from that of DCE. Diffusion-weighted imaging may be preferable to DCE for the preoperative evaluation of stage IB cervical cancer.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Gadolínio DTPA , Aumento da Imagem/métodos , Neoplasias do Colo do Útero/patologia , Adulto , Meios de Contraste , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estadiamento de Neoplasias , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
14.
Hum Vaccin Immunother ; 19(1): 2135852, 2023 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-36628470

RESUMO

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.


Assuntos
Vacinas contra Influenza , Influenza Humana , Humanos , Pessoal de Saúde/educação , Influenza Humana/prevenção & controle , Influenza Humana/epidemiologia , Vacinação
15.
J Comput Assist Tomogr ; 36(1): 54-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22261770

RESUMO

PURPOSE: To investigate the apparent diffusion coefficients (ADCs) of the normal uterine zonal structures (myometrium, endometrium, and junctional zone) during different phases of the menstrual cycle among premenopausal women with different age groups. MATERIALS AND METHODS: Magnetic resonance (MR) images of 67 healthy women were obtained during the midproliferative and midsecretory phases. They were further divided into 3 age groups: group A (age range, 20-29 years); group B (age range, 30-39 years), and group C (mean age, 44.62 years; age range, 40-49 years). All the women underwent 3.0-T MR scanning twice. The ADC values were compared among each uterine zonal structure and 3 age groups and were calculated between the midproliferative and midsecretory phase. RESULTS: The ADC values among each uterine zonal structures were significantly different from one another (P < 0.001). The ADC values for endometrium in women in their 30s were higher than those in their 20s and in their 30s during the midproliferative and midsecretory phases (P < 0.05), and the ADC values for endometrium in each age groups were lower during the midproliferative phase than those during the midsecretory phase (P < 0.05), but there were no statistical differences in the myometrium and the junctional zone between the 2 phases or among age groups (P > 0.05). CONCLUSION: These preliminary results suggested that the zone, age, and phase of the menstrual cycle in premenopausal women should be considered when interpreting the ADC values of uterine structures (especially for endometrium).


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Pré-Menopausa , Útero/anatomia & histologia , Adulto , Análise de Variância , Feminino , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Ciclo Menstrual , Pessoa de Meia-Idade
16.
Materials (Basel) ; 15(13)2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35806522

RESUMO

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.

17.
Food Chem ; 375: 131834, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34920308

RESUMO

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.


Assuntos
Óleos Voláteis , Perilla , Solventes Eutéticos Profundos , Destilação , Folhas de Planta , Solventes , Ultrassom
18.
World Neurosurg ; 151: e137-e145, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33831613

RESUMO

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.


Assuntos
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 Retrospectivos
19.
J Magn Reson Imaging ; 31(5): 1054-60, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20432338

RESUMO

PURPOSE: To characterize and evaluate functional and anatomic changes of visual pathway lesions during hyperbaric oxygen (HBO) treatment with blood-oxygenation-level-dependent functional MRI (BOLD-fMRI) and diffusion tensor imaging (DTI). MATERIALS AND METHODS: Sixteen patients with visual pathway lesions received HBO treatment. Both BOLD-fMRI and DTI were performed before and after the treatment, while 12 healthy subjects were also studied with 2 examinations as control. The t-tests were used for the comparison of number of activated voxels (AVs) and fractional anisotropy (FA) between the two groups, and within the patient group before and after HBO treatment. Visual acuity of the patient group before and after the treatment was compared using Wilcoxon signed-rank test. RESULTS: Before the treatment, both AVs (P < 0.01) and FA (P < 0.05) in the bilateral cortexes of occipital lobes were significantly less in the patient group than in the control group. After the treatment, both AVs (P < 0.05) and FA (P < 0.05) were significantly increased. Moreover, The FA of 6 patients with lesions in the optical nerve was greater than the FA of the other 10 patients with lesions in the optic radiation (P < 0.05). CONCLUSION: BOLD-fMRI combined with DTI was useful for the characterization and evaluation of anatomic and functional changes of visual pathway lesions and their development during HBO treatment.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Oxigenoterapia Hiperbárica/efeitos adversos , Imageamento por Ressonância Magnética/métodos , Córtex Visual/lesões , Córtex Visual/patologia , Vias Visuais/lesões , Vias Visuais/patologia , Adolescente , Adulto , Idoso , Lesões Encefálicas/etiologia , Lesões Encefálicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
20.
World Neurosurg ; 139: e677-e685, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32339742

RESUMO

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.


Assuntos
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 Retrospectivos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA