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1.
J Antimicrob Chemother ; 79(6): 1353-1361, 2024 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-38656557

RESUMO

BACKGROUND: The clinical candidate alpibectir augments the activity of, and overcomes resistance to, the anti-TB drug ethionamide in vitro and in vivo. OBJECTIVES: A Phase 1, double-blind, randomized, placebo-controlled study to investigate the safety, tolerability, pharmacokinetics (PK) and food effect of alpibectir administered as single and multiple oral doses in healthy volunteers (NCT04654143). METHODS: Eighty participants were randomized. In single ascending dose (SAD), a total of six dose levels of alpibectir (0.5 to 40 mg) were tested under fasted and fed (10 mg) conditions as single daily doses in sequential cohorts. In multiple ascending dose (MAD), repeat doses (5 to 30 mg) were administered once daily for 7 days in three sequential cohorts. RESULTS: No serious adverse event was reported. Thirteen participants across groups experienced a total of 13 mild or moderate treatment-emergent adverse events. Alpibectir showed rapid absorption after single dose (mean Tmax range of 0.88 to 1.53 h). Food affected the PK of alpibectir, characterized by a slower absorption (mean Tmax 3.87 h), a lower Cmax (-17.7%) and increased AUC0-t (+19.6%) compared with the fasted condition. Following repeat dosing, dose proportionality was shown for both Cmax and AUC0-tau. Accumulation of alpibectir was observed across all doses, with a more profound effect on AUC during a dosing interval (AUC0-tau) compared with Cmax (1.8- and 1.3-fold on average), respectively. Steady state was considered to have been achieved by Day 7 of dosing. CONCLUSIONS: Alpibectir was generally well tolerated, and no clinically relevant safety findings were identified in the participants treated during SAD or MAD. The PK is dose-proportional and affected by food.


Assuntos
Antituberculosos , Voluntários Saudáveis , Humanos , Adulto , Masculino , Feminino , Método Duplo-Cego , Adulto Jovem , Pessoa de Meia-Idade , Antituberculosos/farmacocinética , Antituberculosos/administração & dosagem , Antituberculosos/efeitos adversos , Interações Alimento-Droga , Administração Oral , Adolescente , Placebos/administração & dosagem , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos
2.
Int. j. morphol ; 41(3): 845-850, jun. 2023. tab
Artigo em Inglês | LILACS | ID: biblio-1514299

RESUMO

SUMMARY: The aim of this cross-sectional study was to compare dietary intake to published recommendations and to analyze the potential relationship between body composition and dietary intake in collegiate athletes. Eighteen healthy male middle- and long- distance runners (age 20.11 ± 2.72 y; height, 174.7 ± 6.1 cm; body mass, 64.0 ± 7.7 kg), were recruited from a Mexican university track and field team at the beginning of the general preparation phase for national competitions. Participants completed three 24-hour dietary recalls, which were used to estimate dietary intake. Body composition was measured by Dual-energy X-ray absorptiometry (DXA). Athletes displayed high body fat values. Protein intake was significantly higher than published recommendations. Iron, zinc, sodium, and vitamin C intake were significantly higher than recommended values, while potassium and calcium intake were below established recommendations. No significant correlations between body composition variables (i.e body fat, lean body mass, bone mineral content) and dietary intake (i.e energy, macronutrients and selected vitamins and minerals) could be found. These findings suggest that coaches and practitioners should pay close attention to dietary intake and body composition of endurance athletes starting general preparation for competition. Future studies on changes of dietary intake and body composition during off-season and competitive phase, which also track physical activity, are warranted.


El objetivo de este estudio transversal fue comparar la ingesta dietética con las recomendaciones publicadas y analizar la relación potencial entre la composición corporal y la ingesta dietética en corredores universitarios. Dieciocho atletas masculinos sanos de media y larga distancia (edad 20,11 ± 2,72 años; altura, 174,7 ± 6,1 cm; masa corporal, 64,0 ± 7,7 kg), fueron reclutados de un equipo de atletismo de una universidad mexicana al comienzo de la fase de preparación general de competiciones nacionales. Los participantes completaron tres recordatorios dietéticos de 24 horas, que se utilizaron para estimar la ingesta dietética. La composición corporal se midió mediante absorciometría de rayos X de energía dual (DXA). Los atletas mostraron altos valores de grasa corporal. La ingesta de proteínas fue significativamente mayor que las recomendaciones publicadas. La ingesta de hierro, zinc, sodio y vitamina C fue significativamente superior a los valores recomendados, mientras que la ingesta de potasio y calcio estuvo por debajo de las recomendaciones establecidas. No se encontraron correlaciones significativas entre las variables de composición corporal (es decir, grasa corporal, masa corporal magra, contenido mineral óseo) y la ingesta dietética (es decir, energía, macronutrientes y vitaminas y minerales seleccionados). Estos hallazgos sugieren que los entrenadores y los practicantes deberían prestar mucha atención a la ingesta dietética y la composición corporal de los atletas de resistencia que comienzan la preparación general para la competencia. Se justifican estudios futuros sobre los cambios en la ingesta dietética y la composición corporal durante la fase fuera de temporada y competitiva, como también un seguimiento de la actividad física.


Assuntos
Humanos , Masculino , Adulto Jovem , Corrida , Composição Corporal , Dieta , Ingestão de Alimentos , Estudantes , Universidades , Absorciometria de Fóton , Tecido Adiposo , Estudos Transversais
3.
Artigo em Espanhol | LILACS, CUMED | ID: biblio-1449920

RESUMO

La hipoxantina y la xantina son biomarcadores metabólicos que resultan de la degradación de las proteínas purinas. Los análisis cienciométricos constituyen una herramienta para estudiar las publicaciones científicas en torno a un determinado tema con la finalidad de determinar tendencias en la literatura. Se realizó un análisis cienciométrico de la producción científica reciente sobre la hipoxantina y xantina en el ejercicio, publicada en la base de datos Scopus durante el período 2016 - 2021. Para la búsqueda en Scopus se utilizaron las palabras clave en idioma inglés: exercise, hypoxanthine y xanthine. Se realizó un análisis cuantitativo, tomando en cuenta los artículos encontrados, así como la información proporcionada por el software VOSviewer. Se identificaron 64 artículos, de estos, 56 fueron de investigación aplicada y ocho de revisión. La categoría de efecto del ejercicio tuvo una mayor cantidad de estudios con 23; dentro de esta se encuentra la subcategoría de metabolismo que presentó 21 artículos. Tanto Estados Unidos como Polonia son los países con mayor número de publicaciones. Existen distintos enfoques y protocolos de ejercicio utilizados para cuantificar la respuesta de la hipoxantina y xantina, así como los perfiles de los sujetos de estudio utilizados como muestra para las investigaciones. La cuantificación de hipoxantina y xantina en el cuerpo es importante para la investigación en el campo de las ciencias del ejercicio(AU)


Hypoxanthine and xanthine are metabolic biomarkers that result from the degradation of purine proteins. Scientometric analyzes constitute a tool to study scientific publications around a certain topic in order to determine trends in the literature. A scientometric analysis was carried out of the recent scientific production on hypoxanthine and xanthine in exercise, published in Scopus database during the period 2016-2021. For the search in Scopus, we used the English keywords exercise, hypoxanthine and xanthine. A quantitative analysis was carried out, taking into account the articles found, as well as the information provided by VOSviewer software. Sixty-four articles were identified, 56 of them were applied research and eight were review. The exercise effect category had a larger number of studies (23). Here there is a subcategory of metabolism that had 21 articles. The United States and Poland are both the countries with the highest number of publications. There are different approaches and exercise protocols used to quantify the response of hypoxanthine and xanthine, as well as the profiles of the study subjects used as a sample for the investigations. The quantification of hypoxanthine and xanthine in the body is important for research in the field of exercise science(AU)


Assuntos
Humanos , Masculino , Feminino , Xantinas , Exercício Físico , Fadiga Muscular , Indicadores de Produção Científica , Hipoxantinas
4.
BMC Neurosci ; 18(1): 13, 2017 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-28086802

RESUMO

BACKGROUND: Magnetic resonance spectroscopy (MRS) provides non-invasive information about the metabolic pattern of the brain parenchyma in vivo. The SpectraClassifier software performs MRS pattern-recognition by determining the spectral features (metabolites) which can be used objectively to classify spectra. Our aim was to develop an Infarct Evolution Classifier and a Brain Regions Classifier in a rat model of focal ischemic stroke using SpectraClassifier. RESULTS: A total of 164 single-voxel proton spectra obtained with a 7 Tesla magnet at an echo time of 12 ms from non-infarcted parenchyma, subventricular zones and infarcted parenchyma were analyzed with SpectraClassifier ( http://gabrmn.uab.es/?q=sc ). The spectra corresponded to Sprague-Dawley rats (healthy rats, n = 7) and stroke rats at day 1 post-stroke (acute phase, n = 6 rats) and at days 7 ± 1 post-stroke (subacute phase, n = 14). In the Infarct Evolution Classifier, spectral features contributed by lactate + mobile lipids (1.33 ppm), total creatine (3.05 ppm) and mobile lipids (0.85 ppm) distinguished among non-infarcted parenchyma (100% sensitivity and 100% specificity), acute phase of infarct (100% sensitivity and 95% specificity) and subacute phase of infarct (78% sensitivity and 100% specificity). In the Brain Regions Classifier, spectral features contributed by myoinositol (3.62 ppm) and total creatine (3.04/3.05 ppm) distinguished among infarcted parenchyma (100% sensitivity and 98% specificity), non-infarcted parenchyma (84% sensitivity and 84% specificity) and subventricular zones (76% sensitivity and 93% specificity). CONCLUSION: SpectraClassifier identified candidate biomarkers for infarct evolution (mobile lipids accumulation) and different brain regions (myoinositol content).


Assuntos
Isquemia Encefálica/classificação , Encéfalo/metabolismo , Processamento de Imagem Assistida por Computador/métodos , Espectroscopia de Ressonância Magnética , Software , Acidente Vascular Cerebral/classificação , Animais , Encéfalo/diagnóstico por imagem , Isquemia Encefálica/diagnóstico por imagem , Isquemia Encefálica/metabolismo , Creatina/metabolismo , Inositol/metabolismo , Ácido Láctico/metabolismo , Metabolismo dos Lipídeos , Masculino , Metaboloma , Metabolômica/métodos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/metabolismo
5.
Rev. psicol. deport ; 26(supl.2): 125-131, 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-166127

RESUMO

El objetivo del presente estudio fue analizar los niveles de cortisol en plasma y su relación con la percepción de los niveles de estrés y recuperación en jugadores de balonmano durante un periodo de entrenamiento y competición. Participaron 14 jugadores de balonmano durante una competición nacional. Se recogieron un total de seis muestras de cortisol y se hicieron cuatro aplicaciones del RESTQ-Sport. Se observó disminución significativa (p < .01) en los niveles de cortisol post-competición (162.22 ± 69.83 ng/mL) en relación a la pre-competición (243.81 ± 36.46 ng/mL). Las sub-escalas de estrés general, estrés emocional, fatiga, recuperación física, calidad de sueño y periodos de descanso alterados del RESTQ-Sport presentaron cambios significativos entre las tomas pre y post-competición. Se encontró una correlación positiva entre los niveles de cortisol y la subescala de éxito (rho = .53; p < .05) y una negativa con la de lesiones (rho = -.57; p < .05). El estudio apoya el concepto de la respuesta anticipatoria del cortisol en relación a la competición. Además, proporciona mayor evidencia de la influencia del entrenamiento y la competición sobre la percepción del estrés-recuperación, resaltando la importancia de un registro psicofisiológico y hormonal con el objetivo de alcanzar un rendimiento deportivo óptimo (AU)


The aim of the study was to analyze plasma cortisol levels and their relation with the perception of recovery-stress balance in handball players during a training and competition period. Fourteen handball players took part in the study during a major competition. Data were collected from six blood samples in order to measure cortisol, and from four applications of the RESTQ-Sport for stress-recovery balance assessment. Compared to pre-competition (243.81 ± 36.46 ng/mL), a significative decrease (p < .01) in cortisol levels was observed in post-competition (162.22 ± 69.83 ng/mL). The RESTQ-Sport subscales general stress, emotional stress, fatigue, physical recovery, sleep quality, and disturbed breaks showed significant changes between pre and post-competition. Cortisol levels were found to have positive correlation with success subscale (rho = .53; p < .05), whilst negative with fitness/injury subscale (rho = -.57; p < .05). Our findings support the idea of an anticipatory cortisol response to competition. Moreover, they provide further evidence on the influence of training over recovery-stress perception, emphasizing the importance of the psychophysiological and hormonal monitoring in order to achieve optimal athletic performance (AU)


O objetivo deste estudo foi analisar os níveis de cortisol plasmático e sua relação com a percepção dos níveis de estresse e recuperação em jogadores de handebol durante um treinamento e competição. Participaram 14 jogadores de handebol durante uma competição nacional. Um total de seis amostras de cortisol foram recolhidas e quatro aplicações do RESTQ-Sport foram feitas. Foi observada uma diminuição significativa (p < .01) nos níveis de cortisol pós-competição (162,22 ± 69,83 ng / mL) em relação ao pré-competição (243,81 ± 36,46 ng / mL). As sub-escalas de estresse geral, estresse emocional, fadiga, recuperação física, qualidade do sono e de repouso alterados do RESTQ-Sport mostrou mudanças significativas entre as ingestões pré e pós-competição. Se encontrou uma correlação positiva entre os níveis de cortisol e a sub-escala de sucesso (rho = 0,53; p < .05) e uma correlação negativa com lesão (rho = -.57; p < .05). O estudo apoia o conceito de resposta do cortisol antecipatória em relação à competição. Ele também fornece mais uma prova da influência do treinamento e competição na percepção de estresse-recuperação, destacando a importância de um registo psicofisiológica e hormonal a fim de alcançar o desempenho atlético ideal (AU)


Assuntos
Humanos , Hidrocortisona , Estresse Fisiológico/fisiologia , Esportes/fisiologia , Descanso/fisiologia , Monitorização Fisiológica/métodos , Ensaio de Imunoadsorção Enzimática
6.
Rev. psicol. deport ; 26(supl.2): 157-163, 2017. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-166131

RESUMO

La actividad física de alta intensidad o competencia puede generar daño muscular pudiendo afectar el rendimiento de los atletas. El objetivo del presente estudio fue determinar si los antioxidantes presentes en la zarzamora favorecen el proceso de recuperación sobre el daño muscular en atletas a través de la cuantificación de creatincinasa (CK) y urea tras una semana de competencia. Se evaluó la CK y urea en plasma del grupo experimental (GE) y un grupo placebo (GP), en las siguientes etapas: (basal) previo a la ingesta del jugo, (pre) al inicio de la competencia, (final) al final de la competencia, (24h), (48h) y (72h) finalizado el último partido. En relación a la CK, se observaron diferencias significativas en el GE en las etapas de pre y la final con respecto a la basal (p < 0.05), en la toma final con respecto a la pre (p < 0.05) y en la toma 48h y 72h con relación a la final (p < 0.05). En el GP únicamente se encontraron diferencias significativas (p < 0.05) entre las tomas 48h y 72h con relación a la final. En la concentración de urea se presentó diferencia en las tomas final, 24h y 48 h con relación a la pre (p < 0.05), en el GP no hubo diferencias significativas en ninguna de las tomas. Estos resultados sugieren que el consumo de zarzamora contribuye a la recuperación del daño muscular (AU)


High intensity physical activity can provoke muscle damage and consequently affect athletes’ performance. The aim of this study was to determine if antioxidants contained in blackberry can stimulate athletes’ processes of recovery from muscle damage, using Creatine Kinase (CK) quantification and urea values after a week of competition as indicators. Participants were divided into an experimental (EG) and a placebo group (CG). In both groups, CK and urea in plasma were measured before, during and after competition. Significant differences were observed in EG at pre and post phases, compared to the basal (p < 0.05). Further, significant differences were found in the pre-post analysis of EG (p < 0.05), as well as after 48h and 72h compared with post-test (p < 0.05). Significant differences were also found for CG (p < 0.05) at 48h and 72h compared to post-test. As regard to urea concentration, differences were shown at post-test, after 24h, and after 48h compared to pre-test (p < 0.05). CG showed no significant differences at any stage of the research. These results suggest that consumption of blackberries may contribute to muscle damage recovery (AU)


A atividade física de alta intensidade ou a competição pode levar a lesão muscular e pode afetar o desempenho dos atletas. O objectivo deste estudo foi determinar se antioxidantes presentes na amora-preta favorecem o processo de recuperação de danos musculares em atletas através da quantificação da creatina quinase (CK) e ureia após uma semana de competição. CK e ureia foi avaliada no plasma do grupo experimental (GE) e um grupo de placebo (GP), nos seguintes passos: (linha de base) antes da ingestão de sumo, (pré) no início da competição (final) para final da competição, (24h), (48h) e (72h) no término o último jogo. No que diz respeito a CK, tiveram diferenças significativas no GE no pré e último em relação ao basal (p< .05), na ingestão final sobre a pré (p < .05) e na ingestão 48h e 72h em relação à final (p < .05). No GP unicamente foram encontradas diferenças significativas (p < .05) entre as ingestões 48h e 72h em relação à final. Na concentração de ureia apareceu uma diferença nas ingestões finais, 24h e 48 h em relação ao pré (p < .05) no GP não houve diferenças significativas em nenhumas das ingestões. Estes resultados sugerem que o consumo de amorapreta contribui para a recuperação de lesões musculares (AU)


Assuntos
Humanos , Traumatismos em Atletas/prevenção & controle , Rubus , Músculos/lesões , Extratos Vegetais/farmacocinética , Substâncias Protetoras/farmacocinética , Creatina Quinase/sangue , Antioxidantes/farmacocinética , Ureia/sangue
7.
Biopreserv Biobank ; 14(2): 156-64, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26886080

RESUMO

BACKGROUND: Biopsies extracted from brain cancer patients often display degraded ribosomal RNA, which makes them unusable in transcriptomic experiments. This has not been properly documented in previous works aimed at refining the molecular classification of brain cancer. OBJECTIVE: To determine RNA integrity in a large cohort of human brain cancer biopsies and to evaluate different factors that may influence RNA integrity in both a murine model of glioblastoma and in additional subsets of patient biopsies. METHODS: Total RNA was isolated from 255 biopsies of various human brain tumors (HBTs) and processed on a Bioanalyzer. Correct RNA integrity was considered for samples showing either the ribosomal 28S/18S peak ratio ≥ 1.2 or RNA integrity number ≥ 6. The time-dependent effect of ex vivo ischemia was evaluated in a murine model, whose results were tested in a new collection of 27 human biopsies. Multiple biopsy sampling was considered in a further set comprising 32 biopsies. RESULTS: The 255 human biopsies revealed a substantial percentage of samples displaying degraded RNA (27.5%). The murine model confirmed the known relevance of ex vivo ischemia time in increased RNA degradation. Human biopsies extracted immediately after cauterization showed a trend toward less RNA degradation. Combining snap freezing and multiple sampling of biopsies, the percentage of patients with degraded RNA was reduced by twofold (15.6%). CONCLUSIONS: We provide a first concise study of factors influencing RNA degradation in HBT biopsies. Immediate biopsy removal after cauterization of the tumor area, snap freezing, and multiple sampling improve RNA quality.


Assuntos
Neoplasias Encefálicas/genética , RNA Ribossômico/genética , Animais , Biópsia , Temperatura Corporal , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos C57BL
8.
J Cereb Blood Flow Metab ; 35(5): 828-34, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25605287

RESUMO

Ex vivo high-resolution magic-angle spinning (HRMAS) provides metabolic information with higher sensitivity and spectral resolution than in vivo magnetic resonance spectroscopy (MRS). Therefore, we used both techniques to better characterize the metabolic pattern of the infarct and the neural progenitor cells (NPCs) in the ipsilateral subventricular zone (SVZi). Ischemic stroke rats were divided into three groups: G0 (non-stroke controls, n = 6), G1 (day 1 after stroke, n = 6), and G7 (days 6 to 8 after stroke, n = 12). All the rats underwent MRS. Three rats per group were analyzed by HRMAS. The remaining rats were used for immunohistochemical studies. In the infarct, both techniques detected significant metabolic changes. The most relevant change was in mobile lipids (2.80 ppm) in the G7 group (a 5.53- and a 3.95-fold increase by MRS and HRMAS, respectively). In the SVZi, MRS did not detect any significant metabolic change. However, HRMAS detected a 2.70-fold increase in lactate and a 0.68-fold decrease in N-acetylaspartate in the G1 group. None of the metabolites correlated with the 1.37-fold increase in NPCs detected by immunohistochemistry in the G7 group. In conclusion, HRMAS improves the metabolic characterization of the brain in experimental ischemic stroke. However, none of the metabolites qualifies as a surrogate biomarker of NPCs.


Assuntos
Infarto Encefálico/metabolismo , Ventrículos Laterais/metabolismo , Acidente Vascular Cerebral/metabolismo , Animais , Biomarcadores/metabolismo , Infarto Encefálico/patologia , Modelos Animais de Doenças , Ventrículos Laterais/patologia , Espectroscopia de Ressonância Magnética , Masculino , Ratos , Ratos Sprague-Dawley , Acidente Vascular Cerebral/patologia , Fatores de Tempo
9.
MAGMA ; 25(5): 401-10, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22286777

RESUMO

OBJECT: High-resolution magic angle spinning (HRMAS) magnetic resonance spectroscopy provides detailed metabolomic information from intact tissue. However, long acquisition times and high rotation speed may lead to timedependent spectral pattern changes, which may affect proper interpretation of results. We report a strategy to minimize those changes, even at physiological recording temperature. MATERIALS AND METHODS: Glioblastoma(Gbm) tumours were induced in 12 mice by stereotactic injection of GL261 cells. Animals were sacrificed and tumours were removed and stored in liquid N2. Half of the samples were exposed to focused microwave (FMW) irradiation prior to HRMAS while the other half was not. Time-course experiments (374 min at 37°C, 9.4T, 3,000 Hz spinning rate) were carried out to monitor spectral pattern changes. Differences were assessed with Unianova test while post-HRMAS histopathology analysis was performed to assess tissue integrity. RESULTS: Significant changes (up to 1.7 fold) were observed in samples without FMW irradiation in several spectral regions e.g. mobile lipids/lactate (0.90-1.30 ppm), acetate (1.90 ppm), N-acetyl aspartate (2.00 ppm), and Choline-containing compounds (3.19-3.25 ppm). No significant changes in the spectral pattern of FMW-irradiated samples were recorded. CONCLUSION: We describe here a successful strategy to minimize spectral pattern changes in mouse Gbm samples using a FMW irradiation system.


Assuntos
Neoplasias Encefálicas/patologia , Encéfalo/patologia , Glioblastoma/patologia , Espectroscopia de Ressonância Magnética/métodos , Animais , Linhagem Celular Tumoral , Colina/química , Humanos , Lipídeos/química , Metabolômica/métodos , Camundongos , Camundongos Endogâmicos C57BL , Micro-Ondas , Modelos Estatísticos , Transplante de Neoplasias , Neoplasias/patologia , Temperatura , Fatores de Tempo
10.
MAGMA ; 23(4): 203-15, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20549297

RESUMO

OBJECT: To investigate the effect of temperature (0 versus 37 degrees C) in the high-resolution magic angle spinning spectroscopy (HRMAS) pattern of human brain tumor biopsies and its influence in recognition-based tumor type prediction. This proof-of-principle study addressed the bilateral discrimination between meningioma (MM) and glioblastoma multiforme (GBM) cases. MATERIALS AND METHODS: Forty-three tumor biopsy samples were collected (20 MM and 23 GBM), kept frozen and later analyzed at 0 degrees C and 37 degrees C by HRMAS. Post-HRMAS histopathology was used to validate the tumor type. Time-course experiments (100 min) at both temperatures were carried out to monitor HRMAS pattern changes. Principal component analysis and linear discriminant analysis were used for classifier development with a training set of 20 biopsies. RESULTS: Temperature-dependent, spectral pattern changes mostly affected mobile lipids and choline-containing compounds resonances and were essentially reversible. Incubation of 3 MM and 3 GBM at 37 degrees C during 100 minutes produced irreversible pattern changes below 13% in a few resonances. Classification performance of an independent test set of 7 biopsies was 100% for the pulse-and-acquire, CPMG at echo times (TE) of 30 ms and 144 ms and Hahn Echo at TE 30 ms at 0 degrees C and 37 degrees C. The performance for Hahn Echo spectra at 136 ms was 83.3% at 0 degrees C and 100% at 37 degrees C. CONCLUSION: The spectral pattern of mobile lipids changes reversibly with temperature. HRMAS demonstrated potential for automated brain tumor biopsy classification. No advantage was obtained when acquiring spectra at 37 degrees C with respect to 0 degrees C in most of the conditions used for the discrimination addressed.


Assuntos
Biópsia , Neoplasias Encefálicas/patologia , Espectroscopia de Ressonância Magnética , Biomarcadores Tumorais/análise , Neoplasias Encefálicas/química , Neoplasias Encefálicas/metabolismo , Análise Discriminante , Humanos , Modelos Lineares , Análise de Componente Principal , Temperatura , Fatores de Tempo
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