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Background: The diagnosis of dementia is complicated due to the frequent coexistence of degenerative changes and the lack of uniformity in diagnostic criteria. Objective: To determine the correlation between computed tomography and risk factors in patients with dementia. Methods: 100 patients with a diagnosis of senile dementia, vascular dementia, or Alzheimer's disease were studied. Vascular risk factors included diabetes mellitus, hypertension, cerebrovascular disease, and hypercholesterolemia. CT scans and Hachinski Ischemic scores were recorded. Results: A total of 100 patients (69 women, 31 men) with the prevalence of dementia were studied. The average for women was 79.81 ± 8.2 years. Metabolic concentrations were of no significant value, provided 56% had risk factors such as hypertension. Symptom onset was recorded at 41.39 ± 30.08 months. Computed tomography revealed that 16 % presented signs of ischemia, 12 % cortico-subcortical atrophy, 1 % infarction, and 1% were detected with signs of frontal-parietal flattening. Conclusions: It is possible to use computed tomography in conjunction with vascular risk factors to detect cognitive impairment.

Homogeneous extremely low-frequency electromagnetic fields (ELF-EMFs) alter biological phenomena, including the cell phenotype and proliferation rate. Heterogenous vortex magnetic fields (VMFs), a new approach of exposure to magnetic fields, induce systematic movements on charged biomolecules from target cells; however, the effect of VMFs on living systems remains uncertain. Here, we designed, constructed, and characterized an ELF-VMF-modified Rodin's coil to expose SH-SY5Y cells. Samples were analyzed by performing 2D-differential-gel electrophoresis, identified by MALDI-TOF/TOF, validated by western blotting, and characterized by confocal microscopy. A total of 106 protein spots were differentially expressed; 40 spots were downregulated and 66 were upregulated in the exposed cell proteome, compared to the control cell proteome. The identified spots are associated with cytoskeleton and cell viability proteins, and according to the protein-protein interaction network, a significant interaction among them was found. Our data revealed a decrease in cell survival associated with apoptotic cells without effects on the cell cycle, as well as evident changes in the cytoskeleton. We demonstrated that ELF-VMFs, at a specific frequency and exposure time, alter the cell proteome and structurally affect the target cells. This is the first report showing that VMF application might be a versatile system for testing different hypotheses in living systems, using appropriate exposure parameters.© 2022 Bioelectromagnetics Society.

The registration of a 3D model over an image can be seen as the alignment of visual correspondences extracted from these two data. This is a challenging task and it is even more complex when the two images have a different modality. This paper introduces an approach that allows matching features detected in two different modalities: photographs and 3D models, by using a common 2D representation. Our approach is based on a modification of the Marching Cubes algorithm aiming to remove ambiguous cases without adding further calculations in each cube. We share the idea about the crucial importance of splitting the equivalence cases into two classes. Considering all the possible states inside/outside in the four corners of a cube side, indeed, there are only four non-trivial cases after eliminating those equivalences through the rotation. The obtained results allow us to validate the feasibility of the proposed methodology.

Computational approaches have been used for analyzing risk factors together with conventional mammograms for breast cancer detection. Currently, other screening methods like electro-impedance mammography are available. Notwithstanding, as far as we know there is not related work evaluating the role of electrical-conductivity index of the mammary gland as a quantitative factor for early detection of breast cancer. This paper aims to demonstrate the importance of including breast conductivity index as a quantitative local risk-factor by analyzing a dataset of Mexican patients from a machine learning perspective. There are 12 attributes distributed into two groups: electrical-conductivity (3) and medical records (9). According to the obtained results with unsupervised methods, the performance in terms of accuracy of using only electrical-conductivity (43%) is better than using all available features (38%) and the medical records (33%). On the other hand, we identified that SVM achieves higher results in comparison with other algorithms when only the electrical-features are used. The obtained results demonstrate the important role of conductivity index as a quantitative local risk-factor for being considered in screening processes. Besides, it emerges as an important aspect to be included in the development of automatic tools for experts to perform breast cancer diagnosis.

An exhaustive characterization of the physicochemical properties of gum arabic (GA)-coated Fe3O4 magnetic nanoparticles was conducted in this work. These nanoparticles were obtained via the in-situ coprecipitation method (a fast single-step method) in two GA:Fe ratios, 10:1 and 20:1, respectively. Several experimental techniques were applied in the characterization process, all of them described below. Using Transmission Electron Microcopy images, they were shown to have spherical-like morphology with 11 nm diameter. The Fourier Transform Infrared spectra confirmed the attachment of the GA on the surface of the magnetic nanoparticles (MNPs), providing good colloidal stability from pH 7 to 8. The thickness of the coatings (1.7 nm and 1.1 nm) was determined using thermogravimetric measurements. A high specific absorption rate and superparamagnetic properties were determined using alternant and static magnetic fields, respectively. The GA-coated MNPs were non-cytotoxic, according to tests on HT-29 human intestine cells. Additionally, HT-29 cells were exposed to magnetic fluid hyperthermia at 530 kHz, and the induction of cell death by the magnetic field, due to the heating of GA-coated MNP, was observed.

In this work a comparative theoretical analysis vs. experimental study on human blood under a magnetic field stimulation is presented. Twenty samples of leukoreduced human blood were stimulated with an alternant magnetic field using a Helmholtz coil system; this magnetic field induced an electromotive force in them. Theoretical calculations were performed for the induced electromotive force in a simple model of blood tissue under magnetic stimulation at frequencies: 50 Hz, 100 Hz, 800 Hz, and 1500 Hz. Experimental measurement was performed at the same frequencies for comparison purposes. Results show a high correlation between theoretical and experimental study, as well as effects of agglutination in the stimulated blood cells.

The synthesis and characterization of ytterbium (Yb3+) and erbium (Er3+) co–doped Fe3O4 nanoparticles (NPs) was reported for the first time in this work. A set of samples with fixed Er3+ (1 mol%) and different Yb3+concentrations (1, 10, 20 and 50 mol%) were prepared and systematically characterized to study their structural, magnetic, thermal and optical properties. The superparamagnetic behavior of Fe3O4 and Yb3+ and Er3+co–doped Fe3O4 NPs was verified by the hysteresis loop. The co–doped Fe3O4 NPs also presented an upconversion emission in the green and red region. The Fe3O4 and Fe3O4: Yb3+, Er3+ NPs showed hyperthermic behavior for an externally applied AC magnetic field, observing that the introduction of Yb3+ and Er3+ induced a temperature increase of 34.4% in optimal conditions with respect to the non–doped Fe3O4 with a reduction in saturation magnetization of 7.8%. These observations suggest that Fe3O4: Yb3+, Er3+ NPs turns out to be an important candidate in biomedical applications for simultaneous optical imaging and hyperthermic therapy.

Recently the use of nanomaterials for the diagnosis and detection of malignant diseases has increased due to the versatility and properties of these nanostructures. For this work 60 nm commercial gold nanoparticles (TED PELLA inc.) and Nanostars manufactured by chemical synthesis (precursor reagent: HAuCl4, cationic surfactant: CTAB) of 117 nm were used for coating. Malachite green Isotyocianate (MGITC), mPEG-SH and ortho-pyridyldisulfide-polyethylene glycol-N-succinimidyl propionate (OPSS-PEG-NHS) was used. A SERS active nanoparticle complex was obtained by addition of a solution of MGITC to the gold nanoparticles colloidal solution in a 1:6 ratio. Later, an mPEG-SH solution was added to the mix. The nanoparticle-MGITC-mPEG-SH complex stability was revised using a UV-Vis spectrophotometer and a JEOL JEM 1000 transmission electron microscope. The SERS spectra were registered with a Raman Thermoscientific DXR microscopy system. Amplified bands associated with OPSS-PEG-NHS were identified in 389, 622, 859, 929, 1080, 1283, 1360, 1443, 1490 and 1450 cm-1. The results indicate that through this methodology it is possible to identify gold nanomaterials coated with polymer through the Raman technique. In addition, greater amplification is observed with the use of nanostars compared to gold spheres. Finally, these nanomaterials are available for the marking of specific membrane for the study of different types of cancer by the SERS technique.

In this work a novel approach based on differences of intensities is presented for vascular structures identification in MRI studies such as the time of flight method (TOF). The plating method states that given the high intensities belonging to the vascular system, TOF images can be segmented by thresholding of the histogram. The enhancement of vascular structures is performed by applying a Vesselness filter, and upon completion of a decision based on fuzzy thresholding the error is minimized in the selection of vascular structures. A brief introduction to vascular system problems and how images have helped diagnosis is summarized as well as the history of the different imaging modalities and the evolution of digital images with computers. Segmentation and 3-D reconstruction became image type time of flight; these images are typically used in medical diagnosis of cerebrovascular diseases. The proposed method has less error in segmentation and reconstruction of volumes related to the vascular system, represented in clearer images and less noise compared to edge detection methods.

Human cells with cancer undergo physiological changes at temperatures of 42 °C to 45 °C thereby causing cell death by apoptosis. The methods for achieving these temperatures have already been investigated because of their biomedical application. Magnetic Hyperthermia is an alternative oncology therapy, nevertheless, the temperature distribution in transformed tissue remains unclear at all and its determination in an optimal temperature segment from 42 oC to 45 oC is demanding an answer. COMSOL multiphysics 5.2 is an excellent alternative for giving the answer to the previous question. In this work was made a temperature simulation from several quantities of the nanoparticle. Preliminary results suggest that the temperature gradient drops dramatically as the number of nanoparticles decrease, so that the optimal temperature and nanoparticles number are sought to address efficiently the volume of transformed fabric of interest. As first conclusion, the above was achieved by obtaining the number of particles to be used and an effective separation distance.

Human cells with cancer undergo physiological changes at temperatures of 42 °C to 45 °C thereby causing cell death by apoptosis. The methods for achieving these temperatures have already been investigated because of their biomedical application. Magnetic Hyperthermia is an alternative oncology therapy, nevertheless, the temperature distribution in transformed tissue remains unclear at all and its determination in an optimal temperature segment from 42 oC to 45 oC is demanding an answer. COMSOL multiphysics 5.2 is an excellent alternative for giving the answer to the previous question. In this work was made a temperature simulation from several quantities of the nanoparticle. Preliminary results suggest that the temperature gradient drops dramatically as the number of nanoparticles decrease, so that the optimal temperature and nanoparticles number are sought to address efficiently the volume of transformed fabric of interest. As first conclusion, the above was achieved by obtaining the number of particles to be used and an effective separation distance.

This paper presents an analysis and modeling of electrical impedance spectra applied to the study of experimental data of blood tissue and its main components: red cells, white and plasma. Using the electrical circuit theory yields the transfer functions and the graphic representation of Bode and Nyquist. You can see in this work the experimental technique’s potential to differentiate cellular components of blood tissue, and the usefulness of developing accurate models for analysis. En este trabajo se presenta un análisis y modelado de espectros de impedancia eléctrica aplicados al estudio de datos experimentales de tejido sanguíneo y sus principales componentes: glóbulos rojos, blancos y plasma. Usando la teoría de circuitos eléctricos se obtienen las funciones de transferencia y la representación gráfica de Bode y Nyquist. Se puede ver en este trabajo el potencial de la técnica experimental para diferenciar los elementos que forman al tejido sanguíneo, así como la utilidad de desarrollar modelos precisos para su análisis.

This paper presents two lines of research linking physics, medicine and psychology. The first is the mechanical magnetogastrography used to measure gastric emptying and peristaltic contractions and its relationship to evaluate the physiological behavior related to emotional states. The second is the psicomagnetobiology as a model of induction of cancerstress and biochemical markers that enable the comparison, spectroscopic characterization and imaging using a magnetic scanner, which could be used in the diagnosis and the use of hyperthermia as a treatment for cancer. The Mecano-magnetogastrography is a useful technique for measuring gastric emptying, which is not invasive, does not use ionizing radiation and demonstrates that through the reading of the magnetic fields of magnetic trace ringested can obtain information on gastric emptying and peristaltic contraction, presented reproducible results. In terms of research we call psicomagnetobiology has been used for induction of cancer with N-methyl-N-nitrosourea, resulting in breast cancer 58% of rats.El presente trabajo muestra dos líneas de investigación que vinculan a la física, la medicina y la psicología. La primera consiste en la Mecano-magnetogastrografía que sirve para medirel vaciamiento gástrico así como las contracciones peristálticas las cuales se evaluaron junto con estados emocionales para conocer la influencia del estrés, ansiedad y depresión en las respuestas fisiológicas. La segunda consiste en la psicomagnetobiología como un modelo de inducción de cáncer y de estrés que permiten comparar marcadores bioquímicos, caracterización espectroscópica y obtener imágenes a través de un escáner magnético, la cual podría utilizarse en el diagnóstico y el uso de la hipertermia como tratamiento del cáncer. La Mecano-magnetogastrografía es una técnica útil para medir el vaciado gástrico, que no es invasiva, no usa radiación ionizante y demuestra que a través de la lectura de los campos magnéticos del trazador magnético ingerido se puede obtener información sobre el vaciado gástrico y contracciones peristálticas presentando resultados reproducibles. En cuanto a la línea de investigación que llamamos psicomagnetobiología, se ha usado la inducción de cáncer con N-metil-N-nitrosourea, resultando con cáncer mamario el 58% de las ratas.

En este trabajo se presenta un análisis y modelado de espectros de impedancia eléctrica aplicados al estudio de datos experimentales de tejido sanguíneo y sus principales componentes: glóbulos rojos, blancos y plasma. Usando la teoría de circuitos eléctricos se obtienen las funciones de transferencia y la representación gráfica de Bode y Nyquist. Se puede ver en este trabajo el potencial de la técnica experimental para diferenciar los elementos que forman al tejido sanguíneo, así como la utilidad de desarrollar modelos precisos para su análisis.

El presente trabajo muestra dos líneas de investigación que vinculan a la física, la medicina y la psicología. La primera consiste en la Mecano-magnetogastrografía que sirve para medirel vaciamiento gástrico así como las contracciones peristálticas las cuales se evaluaron junto con estados emocionales para conocer la influencia del estrés, ansiedad y depresión en las respuestas fisiológicas. La segunda consiste en la psicomagnetobiología como un modelo de inducción de cáncer y de estrés que permiten comparar marcadores bioquímicos, caracterización espectroscópica y obtener imágenes a través de un escáner magnético, la cual podría utilizarse en el diagnóstico y el uso de la hipertermia como tratamiento del cáncer. La Mecano-magnetogastrografía es una técnica útil para medir el vaciado gástrico, que no es invasiva, no usa radiación ionizante y demuestra que a través de la lectura de los campos magnéticos del trazador magnético ingerido se puede obtener información sobre el vaciado gástrico y contracciones peristálticas presentando resultados reproducibles. En cuanto a la línea de investigación que llamamos psicomagnetobiología, se ha usado la inducción de cáncer con N-metil-N-nitrosourea, resultando con cáncer mamario el 58% de las ratas.

The use of nanostructured materials has gained strength in recent years in the biomedical area; new applications such as the detection of components in living cells have been used in pharmaceutical area, specifically to study the interaction of various antitumor drugs in living tissues, the detection of genes that are closely related to some type of cancer, as well as the detections of protein biomarkers for diseases also have been studied in various research laboratories around of the world. In this work, we characterize the variation of the absorbance of gold nanoparticles (GNPs) coated with different concentration of Bovine Serum Albumin (BSA) protein. We use GNPS of 60 nm of the trademark-TED PELLA, the BSA protein trademark of Sigma Aldrich and based on that proposed protocol by Chithrani et al., 2009 with purposes to obtain an alternative model to determine the optimal stability of the nanoparticles coated with the protein. The colloidal solutions were prepared with BSA at different concentrations (0.25, 0.5, 0.75 and 1% M/V), and were centrifuged at 15,000 rpm for 90 minutes (centrifuge Model Z383K) and a constant temperature of 25 °C. All the spectra sets were obtained within the range from 400 to 700 nm using an UV-VIS spectrophotometer (Thermo Scientific Model 51118650). The results showed a R2 of 0.99 for an exponential curve correlation between the concentration of BSA, and the absorbance measured. We found at higher concentrations of BSA, there is a decrease in the intensity of the absorption spectra in the plasmon resonance. This preliminary model obtained can be used in the stabilization of gold nanoparticles with different proteins of biomedical interest in future experiments and support for functionalization of GNPs with specific membrane markers.

A noninvasive, sensitive, and specific method of detecting mesenteric ischemia would be of great use in reducing the morbidity and mortality with which it is associated. Acute lesions in polarized electrically coupled tissues lead to injury currents driven by the transmembrane resting potential gradient. These injury currents are an effective indicator of pathophysiology. The presence of near-DC injury currents in rabbit intestinal smooth muscle has already been demonstrated using a Superconducting quantum interference device (SQUID), and the aim of this study was to evaluate the effect of arterial reperfusion upon these currents. We exteriorized the small bowel of 14 New Zealand white rabbits and placed a remotely operated vascular occluder around the distal most artery supplying a 3-in segment of the jejunum. Experiments were conducted in three groups, i.e., control (n=3), ischemia (n=6), and reperfusion following ischemia (n=5). The subject's position was modulated in and out of the biological field detection range of a SQUID magnetometer using a lift constructed of nonmagnetic material. The changes in magnetic field amplitude were 9.3 and 31.01% for the control and ischemia groups, respectively. The reperfusion group first exhibited a decrease of 17.35% from the pre-ischemic to the ischemic period, followed by an increase of 13.88% of the ischemic value after reestablishing perfusion. In conclusion, injury currents in GI smooth muscle that appear during ischemia are reduced to near-pre-ischemic levels during reperfusion.