Comparative MRI analysis of the forebrain of three sauropsida models.

The study of the brain by magnetic resonance imaging (MRI) allows to obtain detailed anatomical images, useful to describe specific encephalic structures and to analyze possible variabilities. It is widely used in clinical practice and is becoming increasingly used in veterinary medicine, even in exotic animals; however, despite its potential, its use in comparative neuroanatomy studies is still incipient. It is a technology that in recent years has significantly improved anatomical resolution, together with the fact that it is non-invasive and allows for systematic comparative analysis. All this makes it particularly interesting and useful in evolutionary neuroscience studies, since it allows for the analysis and comparison of brains of rare or otherwise inaccessible species. In the present study, we have analyzed the prosencephalon of three representative sauropsid species, the turtle Trachemys scripta (order Testudine), the lizard Pogona vitticeps (order Squamata) and the snake Python regius (order Squamata) by MRI. In addition, we used MRI sections to analyze the total brain volume and ventricular system of these species, employing volumetric and chemometric analyses together. The raw MRI data of the sauropsida models analyzed in the present study are available for viewing and downloading and have allowed us to produce an atlas of the forebrain of each of the species analyzed, with the main brain regions. In addition, our volumetric data showed that the three groups presented clear differences in terms of total and ventricular brain volumes, particularly the turtles, which in all cases presented distinctive characteristics compared to the lizards and snakes.

Evaluation of E-beam irradiation and storage time in pork exudates using NMR metabolomics.

Seventy-two exudates from pork tenderloin samples, subjected to E-beam irradiation treatments, have been employed to monitor, through 1H NMR analysis, the effects of irradiation dose (0, 1, 2 and 6 kGy) and storage time (1, 6 and 12 days). As far as we know, this is the first study where meat exudate is employed to monitor the effects of irradiation dose and storage time. The 1H NMR spectra, obtained after ~ 2 min, allowed to determine the main components of the pork exudate. Results show that 1H NMR-based metabolomics provides valuable information about the metabolic changes suffered during storage and how these transformations could be affected by E-beam irradiation treatment. The ease to obtain exudates, the simple NMR sample preparation, the good correlation between the selected metabolites, the irradiation treatment and the storage times point to that this study could be the first step to develop a new method for analysis and control of meat conservation and to evaluate its irradiation treatment.

Use of MRI as a predictive tool for physicochemical and rheologycal features during cured ham manufacturing.

Magnetic resonance imaging (MRI) was used to study the structural changes during dry-cured ham manufacturing. T1, T2 and apparent diffusion coefficient (ADC) were determined. Dry cured hams were analysed at different steps of the manufacturing process (raw, salted, post salted, half-cured and cured). Structural changes were linked with the rheological behaviour, estimated by texture profile analysis (TPA) performed in three different muscles of hams (semimembranosus, semitendinosus and biceps femoris). A decrease for T1, T2 and ADC parameters during the curing process was observed, connected to the dehydration kinetics and salt diffusion. Curing process increased hardness and chewiness and reduced elasticity and cohesiveness. Mathematical models were defined to obtain useful equations to monitor ripening. Multiple and simple linear regression models were performed to predict water and salt content and rheological features evolution through MRI parameters. Best settings were achieved with water and salt content for the three studied muscles (R2 around 0.90). T1, T2 and ADC showed a negative correlation with hardness and a positive relation with springiness and cohesiveness.

[How far reaches earliness of optical coherence tomography in cognitive impairment]. / Hasta donde llega la precocidad de la tomografia de coherencia optica en el deterioro cognitivo?

INTRODUCTION: Alzheimer's disease (AD) is the leading cause of dementia in the world today. Increasingly greater efforts are being made to be able to detect cognitive impairment in earlier stages, and diagnostic entities such as mild cognitive impairment (MCI) and subjective memory complaints (SMC) are appearing. The number of biomarkers studied with the aim of reaching this goal continues to rise, and include optical coherence tomography. SUBJECTS AND METHODS: The study conducted employed optical coherence tomography to measure the macular thickness and the retinal nerve fibre layer in patients diagnosed with AD (n = 36), in patients with MCI (n = 33), in individuals with SMC (n = 24) and in control subjects (n = 45). RESULTS: Statistically significant differences have been found in terms of the macular thickness among all the groups studied (SMC: 261.8 ± 25.88 µm; MCI: 259.19 ± 22.582 µm; mild AD: 258.53 ± 14.804 µm; moderate AD: 249.32 ± 18.467 µm) and control subjects (271.96 ± 15.57 µm). The same occurs as regards the retinal nerve fibre layer and the difference is statistically significant compared with the control group (94.51 ± 9.203 µm) of all the groups (SMC: 90.44 ± 9.059 µm; MCI: 89.4 ± 10.421 µm; mild AD: 87.12 ± 10.279 µm; moderate AD: 82.25 ± 10.636 µm). CONCLUSION: Optical coherence tomography could be a future biomarker and support tool to facilitate the early diagnosis of cognitive impairment and AD.

TITLE: Hasta donde llega la precocidad de la tomografia de coherencia optica en el deterioro cognitivo?Introduccion. La enfermedad de Alzheimer (EA) es la primera causa de demencia mundial. Cada vez son mas los esfuerzos para lograr una deteccion temprana del deterioro cognitivo y surgen en el panorama cientifico entidades diagnosticas como el deterioro cognitivo leve (DCL) y las quejas subjetivas de memoria (QSM). Debido a ello, aparecen numerosos biomarcadores estudiados para conseguir dicho objetivo, entre ellos la tomografia de coherencia optica. Sujetos y metodos. Se ha realizado un estudio que utiliza la tomografia de coherencia optica para medir el grosor macular y la capa de fibras nerviosas de la retina en pacientes diagnosticados de EA (n = 36), pacientes con DCL (n = 33), en individuos con QSM (n = 24) y en sujetos control (n = 45). Resultados. Se han encontrado diferencias estadisticamente significativas en cuanto al grosor macular entre todos los grupos estudiados (QSM: 261,8 ± 25,88 µm; DCL: 259,19 ± 22,582 µm; EA leve: 258,53 ± 14,804 µm; EA moderada: 249,32 ± 18,467 µm) y sujetos control (271,96 ± 15,57 µm). Respecto a la capa de fibras nerviosas de la retina, ocurre de igual manera, y la diferencia es estadisticamente significativa frente al grupo control (94,51 ± 9,203 µm) de todos los grupos (QSM: 90,44 ± 9,059 µm; DCL: 89,4 ± 10,421 µm; EA leve: 87,12 ± 10,279 µm; EA moderada: 82,25 ± 10,636 µm). Conclusion. La tomografia de coherencia optica podria situarse como un futuro biomarcador y una herramienta de apoyo para facilitar el diagnostico precoz del deterioro cognitivo y de la EA.

Label-free magnetic resonance imaging to locate live cells in three-dimensional porous scaffolds.

Porous scaffolds are widely tested materials used for various purposes in tissue engineering. A critical feature of a porous scaffold is its ability to allow cell migration and growth on its inner surface. Up to now, there has not been a method to locate live cells deep inside a material, or in an entire structure, using real-time imaging and a non-destructive technique. Herein, we seek to demonstrate the feasibility of the magnetic resonance imaging (MRI) technique as a method to detect and locate in vitro non-labelled live cells in an entire porous material. Our results show that the use of optimized MRI parameters (4.7 T; repetition time = 3000 ms; echo time = 20 ms; resolution 39 × 39 µm) makes it possible to obtain images of the scaffold structure and to locate live non-labelled cells in the entire material, with a signal intensity higher than that obtained in the culture medium. In the current study, cells are visualized and located in different kinds of porous scaffolds. Moreover, further development of this MRI method might be useful in several three-dimensional biomaterial tests such as cell distribution studies, routine qualitative testing methods and in situ monitoring of cells inside scaffolds.

Magnetic resonance imaging, rheological properties, and physicochemical characteristics of meat systems with fibrinogen and thrombin.

Magnetic resonance imaging (MRI) and textural and physicochemical analyses were carried out to evaluate the effect of fibrinogen and thrombin (Fibrimex) addition to meat systems formulated with and without NaCl. For this purpose, different model systems were elaborated: fibrinogen and thrombin (FT), meat emulsion (ME), and meat emulsion with fibrinogen and thrombin (MEFT), with 0, 1, and 2% of NaCl. The addition of fibrinogen-thrombin to meat emulsions results in a gel network with modified physicochemical and textural characteristics, increasing the hardness and springiness. The addition of NaCl at 2% to FT and MEFT systems reduced the gel hardness. MRI parameters (T2, T1, and apparent diffusion coefficient) indicated that systems with fibrinogen and thrombin (FT and MEFT) presented a structure with many and large pores, bulk water, and higher translational motion of water. Significant correlations were found between MRI, texture, and physicochemical parameters.