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1.
Radiol Med ; 128(8): 891-899, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37310558

RESUMO

PURPOSE: To compare conventional CT images and virtual monoenergetic images (VMI) at dual-layer dual-energy CT (dlDECT) in patients with colorectal cancer (CRC) through quantitative analysis and to investigate the added value of VMI. MATERIAL AND METHODS: Sixty-six consecutive patients with histologically documented CRC and available VMI reconstructions were retrospectively investigated. Subsequently, forty-two patients, without any colonic disease at colonoscopy, were selected as control group. Conventional CT images and VMI reconstructions at energy levels ranging from 40 (VMI40) to 100 keV (VMI100) in 10 keV increments, were obtained from the late arterial phase. First, signal-to-noise (SNR) and contrast-to-noise (CNR) ratios were obtained to select the best VMI reconstruction. Finally, the diagnostic accuracy of conventional CT and VMI40 in late arterial phase was evaluated. RESULTS: On quantitative analysis, SNR and CNR were higher for VMI40 (19.5 ± 7.7 and 11.8 ± 6.2, respectively) with statistically significant differences compared to conventional CT (P < 0.05) and all the other VMI reconstructions (P < 0.05), except for VMI50 (P > 0.05). The addition of VMI40 to conventional CT images significantly improved the area under the curve (AUC) for the diagnosis of CRC, increasing it from 0.875 to 0.943 for reader 1 (P < 0.05) and from 0.916 to 0.954 for reader 2 (P < 0.05). The improvement was greater in the less experienced radiologist (0.068) compared to the more experienced one (0.037). CONCLUSION: VMI40 has showed the highest quantitative image parameters. Furthermore, the use of VMI40 can lead to a significant improvement in the diagnostic performance for detecting CRC.


Assuntos
Neoplasias Colorretais , Imagem Radiográfica a Partir de Emissão de Duplo Fóton , Humanos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Razão Sinal-Ruído , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/métodos , Neoplasias Colorretais/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador/métodos
2.
Eur Spine J ; 28(4): 890, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30739189

RESUMO

Unfortunately, first name and family name in the author group were incorrectly swapped and published. The complete correct names of the author group are given below.

3.
Eur Spine J ; 28(7): 1638-1651, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30673874

RESUMO

BACKGROUND: Several reports in the literature have suggested a causative association between oral occlusion and spinal deformity such as scoliosis and Scheuermann's disease or kyphosis. Based on these findings, a growing number of adolescents with spinal deformity receive orthodontic treatment, supposing a beneficial effect on the spine. OBJECTIVE: The aim of this study was to verify the association between spinal deformity and malocclusion in the orthopedic population and potential effect of orthodontic treatment on the spinal deformity. METHOD: The databases: MEDLINE, CINAHL, EMBASE, Cochrane Register, OTseeker and ScienceDirect were searched up to August 2017 for studies reporting on associations between spinal and occlusal conditions. Case series, cohort, case-control studies and randomized clinical trials were considered for analysis. Two reviewers independently selected studies, conducted quality assessment and extracted results. Methodological quality was assessed using MINORS score. RESULTS: Nine publications reporting on 1424 patients were included. Studies were two case series, five case-control studies, one cohort study and one randomized clinical trial. The methodological quality was poor in 8/9 studies. CONCLUSION: Evidence from three low-quality studies suggests an increased prevalence of occlusal dysfunction in patients with known spinal deformity, but the conclusions have a high risk of bias. No evidence of beneficial effects of orthodontic treatment on spinal deformity was found. These slides can be retrieved under Electronic Supplementary Material.


Assuntos
Cifose/complicações , Má Oclusão/complicações , Doença de Scheuermann/complicações , Escoliose/complicações , Adolescente , Humanos , Má Oclusão/terapia , Ortodontia Corretiva , Resultado do Tratamento
4.
Am J Sports Med ; 49(9): 2332-2340, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34115528

RESUMO

BACKGROUND: An elongation of the radial lateral collateral complex (R-LCL) can provoke symptomatic minor instability of the lateral elbow leading to lateral elbow pain. Biomechanical models investigating the effects of elongation and partial or complete lesions of the R-LCL on lateral elbow stability are lacking. PURPOSE: To evaluate how partial and complete R-LCL release affects radiocapitellar joint stability in a setting of controlled varus load and progressive soft tissue release. STUDY DESIGN: Controlled laboratory study. METHODS: Ten fresh-frozen cadaveric specimens were obtained and mounted on a custom-made support to control elbow flexion and extension and to allow for controlled varus loading. Stress tests were performed on all intact specimens under gravity load alone, a 0.5-kg load applied to the hand, and a 1-kg load applied to the hand. After load application, anteroposterior radiographs were obtained. The following release sequence was applied to all specimens: release of the anterior half of the common extensor origin, pie crusting of the R-LCL, and R-LCL release. After each release, stress tests and radiographs were performed. The varus joint angulation of the elbow (α) was measured by 2 examiners as the main outcome parameter. RESULTS: Significant changes in α from the initial condition occurred after each release, and a significant effect of varus load on α was documented for all release steps. A significant effect of the releases on α could be documented for all identical varus load conditions. A linear regression model was generated to describe the effect of varus load on α. CONCLUSION: Varus loads simulating everyday activities produce changes in the varus joint angulation of the elbow already in the intact specimen, which are linearly dependent on the applied moment and persist after release of the lateral stabilizing structures. With progressive load, a pie crusting of the R-LCL is the minimal procedure able to provoke a significant change in the varus joint angulation, and a complete R-LCL release produces additional increase in the varus joint angulation in all testing conditions. CLINICAL RELEVANCE: These findings confirm the role of the R-LCL as static lateral stabilizer, supporting a pathological model based on its insufficiency and culminating with a symptomatic minor instability of the lateral elbow.


Assuntos
Ligamentos Colaterais , Articulação do Cotovelo , Instabilidade Articular , Ligamentos Laterais do Tornozelo , Fenômenos Biomecânicos , Cadáver , Ligamentos Colaterais/diagnóstico por imagem , Cotovelo , Articulação do Cotovelo/diagnóstico por imagem , Humanos , Amplitude de Movimento Articular
5.
Neurosci Lett ; 388(1): 49-53, 2005 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-16039064

RESUMO

The present study was conducted to determine the concentration of amino acids in the cerebrospinal spinal fluid (CSF) and the activities of two tramsaminases: glutamic oxaloacetate transaminase (GOT) and glutamic pyruvate transaminase (GPT) in human Alzheimer disease (AD) and normal brain. L-glutamic acid, L-glutamine and L-alanine are the most abundant amino acids in the CSF (50-55% of total amino acids). L-glutamine occurs at much higher levels in Alzheimer CSF compared to the normal CSF (229+/-91.8 nmol/ml in AD versus 107+/-47.2 nmol/ml in normal; P=0.0041). In contrast, L-aspartate occurs at significantly lower concentrations in Alzheimer CSF than normal CSF (46.1+/-25.7 nmol/ml in Alzheimer versus 95.2+/-52.6 nmol/ml in normal; P=0.020). In Alzheimer brain (frontal, parietal and occipital cortices) GOT is present at significantly higher activities than in normal brain cortices (about 1.5 times higher; P<0.01). No significant differences for GPT activity occurred between normal and AD brain. Since CSF receives amino acids from brain tissues, and since GOT catalyzes the conversion of L-aspartate to L-glutamate, the higher concentrations of L-glutamine (which is derived from L-glutamate), and the lower concentrations of L-aspartate found in Alzheimer CSF could be considered as a consequence of the higher activity of GOT that occurs in Alzheimer brain.


Assuntos
Doença de Alzheimer/líquido cefalorraquidiano , Doença de Alzheimer/enzimologia , Aminoácidos/líquido cefalorraquidiano , Encéfalo/enzimologia , Líquido Cefalorraquidiano/química , Transaminases/líquido cefalorraquidiano , Idoso , Idoso de 80 Anos ou mais , Alanina Transaminase/líquido cefalorraquidiano , Doença de Alzheimer/fisiopatologia , Aspartato Aminotransferases/líquido cefalorraquidiano , Ácido Aspártico/metabolismo , Encéfalo/fisiopatologia , Química Encefálica/fisiologia , Feminino , Ácido Glutâmico/metabolismo , Glutamina/metabolismo , Humanos , Ventrículos Laterais/enzimologia , Masculino , Pessoa de Meia-Idade , Valores de Referência , Regulação para Cima/fisiologia
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