Use of X-Ray Computed Tomography for Monitoring Tissue Permeation Processes.

Cryoprotectants are essential to prevent ice formation during tissue cryopreservation procedures. However, the control of their concentration and spatial distribution in the tissue is necessary to avoid toxicity and other damages associated with the cryopreservation procedures, especially for bulky samples such as tissues and organs. X-ray computed tomography measures the attenuation of an X-ray beam when it passes through a substance, depending on the material properties of the samples.

Design of a nanoprobe for high field magnetic resonance imaging, dual energy X-ray computed tomography and luminescent imaging.

The combination of different bioimaging techniques, mainly in the field of oncology, allows circumventing the defects associated with the individual imaging modalities, thus providing a more reliable diagnosis. The development of multimodal endogenous probes that are simultaneously suitable for various imaging modalities, such as magnetic resonance imaging (MRI), X-ray computed tomography (CT) and luminescent imaging (LI) is, therefore, highly recommended. Such probes should operate in the conditions imposed by the newest imaging equipment, such as MRI operating at high magnetic fields and dual-energy CT.

Bimodal Nd-Doped LuVO Nanoprobes Functionalized with Polyacrilic Acid for X-Ray Computed Tomography and NIR Luminescent Imaging.

Uniform Nd-doped LuVO nanophosphors have been synthesized for the first time in literature by using a poliol-based method at 120 °C from Nd and vanadate precursors. After optimizing the Nd doping level, these phosphors present intense luminescence in the near-infrared biological windows. The X-ray attenuation capacity of the optimum nanophosphor has been found to be higher than that of a commercial X-ray computed tomography contrast agent.

Stepped vitrification technique for human ovarian tissue cryopreservation.

The advantage of stepped vitrification (SV) is avoiding ice crystal nucleation, while decreasing the toxic effects of high cryoprotectant concentrations. We aimed to test this method for human ovarian tissue cryopreservation. Ovarian cortex was taken from 7 fertile adult women.

Luminescence and X-ray Absorption Properties of Uniform Eu:(HO)LuF Nanoprobes.

Due to the high atomic number of lutetium and the low phonon energy of the fluoride matrix, Lu-based fluoride nanoparticles doped with active lanthanide ions are potential candidates as bioprobes in both X-ray computed tomography and luminescent imaging. This paper shows a method for the fabrication of uniform, water-dispersible Eu:(HO)LuF nanoparticles doped with different Eu contents. Their luminescent properties were studied by means of excitation and emission spectra as well as decay curves.

Synthesis, functionalization and properties of uniform europium-doped sodium lanthanum tungstate and molybdate (NaLa(XO), X = Mo,W) probes for luminescent and X-ray computed tomography bioimaging.

A one-pot simple procedure for the synthesis of uniform, ellipsoidal Eu-doped sodium lanthanum tungstate and molybdate (NaLa(XO), X  = W, Mo) nanophosphors, functionalized with carboxylate groups, is described. The method is based on a homogeneous precipitation process at 120 °C from appropriate Na, Ln and tungstate or molybdate precursors dissolved in ethylene glycol/water mixtures containing polyacrylic acid. A comparative study of the luminescent properties of both luminescent materials as a function of the Eu doping level has been performed to find the optimum nanophosphor, whose efficiency as X-ray computed tomography contrast agent is also evaluated and compared with that of a commercial probe.

Use of X-Ray Computed Tomography for Ice Detection Applied to Organ Cryopreservation.

One of the main problems in the cryopreservation of biological samples is the formation of ice and the consequent mechanical damage to cells and tissues, due to the crystalline structure of ice and its associated mechanical damage. It is necessary to detect this deleterious formation of ice, especially in tissues and organs, because of their large volume and the complexity of their vascular system in the case of bulky organs. In this work, we propose the use of X-ray Computed Tomography (CT) to detect this ice formation inside tissues and organs.

Evaluation of a new freezing protocol containing 20% dimethyl sulphoxide concentration to cryopreserve human ovarian tissue.

Research Question: Could a modification in the ovarian tissue freezing protocol improve follicle survival after cryopreservation and xenotransplantation?

Design: Ovarian tissue was used from 13 adult patients, frozen either with our original protocol, or a modified version involving a higher concentration of dimethyl sulphoxide (DMSO), larger volume of cryopreservation solution and lower seeding temperature. After thawing, the ovarian fragments were xenotransplanted to six mice with severe combined immunodeficiency (SCID) for 3 weeks.

Results: The proportion of primordial follicles decreased, and the proportion of growing follicles increased significantly (all P < 0.

An optimized controlled rate slow cooling protocol for bovine ovarian tissue cryopreservation by means of X-ray computed tomography.

Cryopreservation and subsequent transplantation of ovarian tissue is the only option to preserve fertility in certain patients facing gonadotoxic treatment. So far, cryopreservation of ovarian tissue has been carried out mostly by a controlled rate slow cooling process, typically known as slow freezing. Even though there are still some concerns about the iatrogenic damage on the follicle population, this technique has been used in the more than 100 live births reported to date.

Structural, optical and X-ray attenuation properties of Tb:BaCeF (x = 0.18-0.48) nanospheres synthesized in polyol medium.

Uniform Ba0.18Ce0.82F2.

Room temperature synthesis of water-dispersible Ln:CeF (Ln = Nd, Tb) nanoparticles with different morphology as bimodal probes for fluorescence and CT imaging.

The singular properties of lanthanide-based inorganic nanoparticles (NPs) has raised the attention of the scientific community in biotechnological applications. In particular, those systems with two or more functionalities are especially interesting. In this work, an effective and commercially attractive procedure has been developed that renders uniform, water-dispersible Ln:CeF (Ln = Tb, Nd) NPs with different shapes and size.

Ovarian tissue cryopreservation by stepped vitrification and monitored by X-ray computed tomography.

Ovarian tissue cryopreservation is, in most cases, the only fertility preservation option available for female patients soon to undergo gonadotoxic treatment. To date, cryopreservation of ovarian tissue has been carried out by both traditional slow freezing method and vitrification, but even with the best techniques, there is still a considerable loss of follicle viability. In this report, we investigated a stepped cryopreservation procedure which combines features of slow cooling and vitrification (hereafter called stepped vitrification).

Assessment of the cryoprotectant concentration inside a bulky organ for cryopreservation using X-ray computed tomography.

Cryoprotection of bulky organs is crucial for their storage and for subsequent transplantation. In this work we demonstrate the capability of the X-ray computed tomography (CT) as a non-invasive method to measure the cryoprotectant (cpa) concentration inside a tissue or an organ, specifically for the case of dymethil sulfoxide (Me2SO). It is remarkable that the use of Me2SO has been leader in techniques of cells and tissues cryopreservation.