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1.
Diagnostics (Basel) ; 14(2)2024 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-38275461

RESUMEN

This research addresses the respiratory distress syndrome (RDS) in preterm newborns caused by insufficient surfactant synthesis, which can lead to serious complications, including pneumothorax, pulmonary hypertension, and pulmonary hemorrhage, increasing the risk of a fatal outcome. By analyzing chest radiographs and blood gases, we specifically focus on the significant contributions of these parameters to the diagnosis and analysis of the recovery of patients with RDS. The study involved 32 preterm newborns, and the analysis of gas parameters before and after the administration of surfactants and inhalation corticosteroid therapy revealed statistically significant changes in values of parameters such as FiO2, pH, pCO2, HCO3, and BE (Sig. < 0.05), while the pO2 parameter showed a potential change (Sig. = 0.061). Parallel to this, the research emphasizes the development of a lung segmentation algorithm implemented in the MATLAB programming environment. The key steps of the algorithm include preprocessing, segmentation, and visualization for a more detailed understanding of the recovery dynamics after RDS. These algorithms have achieved promising results, with a global accuracy of 0.93 ± 0.06, precision of 0.81 ± 0.16, and an F-score of 0.82 ± 0.14. These results highlight the potential application of algorithms in the analysis and monitoring of recovery in newborns with RDS, also underscoring the need for further development of software solutions in medicine, particularly in neonatology, to enhance the diagnosis and treatment of preterm newborns with respiratory distress syndrome.

2.
Inflamm Regen ; 43(1): 53, 2023 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-37904253

RESUMEN

BACKGROUND: Chronic non-healing wounds pose a global health challenge. Under optimized conditions, skin wounds heal by the formation of scar tissue. However, deregulated cell activation leads to persistent inflammation and the formation of granulation tissue, a type of premature scar tissue without epithelialization. Regenerative cells from the wound periphery contribute to the healing process, but little is known about their cellular fate in an inflammatory, macrophage-dominated wound microenvironment. METHODS: We examined CD45-/CD31-/CD34+ preadipocytes and CD68+ macrophages in human granulation tissue from pressure ulcers (n=6) using immunofluorescence, immunohistochemistry, and flow cytometry. In vitro, we studied macrophage-preadipocyte interactions using primary human adipose-derived stem cells (ASCs) exposed to conditioned medium harvested from IFNG/LPS (M1)- or IL4/IL13 (M2)-activated macrophages. Macrophages were derived from THP1 cells or CD14+ monocytes. In addition to confocal microscopy and flow cytometry, ASCs were analyzed for metabolic (OXPHOS, glycolysis), morphological (cytoskeleton), and mitochondrial (ATP production, membrane potential) changes. Angiogenic properties of ASCs were determined by HUVEC-based angiogenesis assay. Protein and mRNA levels were assessed by immunoblotting and quantitative RT-PCR. RESULTS: CD45-/CD31-/CD34+ preadipocytes were observed with a prevalence of up to 1.5% of total viable cells in human granulation tissue. Immunofluorescence staining suggested a spatial proximity of these cells to CD68+ macrophages in vivo. In vitro, ASCs exposed to M1, but not to M2 macrophage secretome showed a pro-fibrotic response characterized by stress fiber formation, elevated alpha smooth muscle actin (SMA), and increased expression of integrins ITGA5 and ITGAV. Macrophage-secreted IL1B and TGFB1 mediated this response via the PI3K/AKT and p38-MAPK pathways. In addition, ASCs exposed to M1-inflammatory stress demonstrated reduced migration, switched to a glycolysis-dominated metabolism with reduced ATP production, and increased levels of inflammatory cytokines such as IL1B, IL8, and MCP1. Notably, M1 but not M2 macrophages enhanced the angiogenic potential of ASCs. CONCLUSION: Preadipocyte fate in wound tissue is influenced by macrophage polarization. Pro-inflammatory M1 macrophages induce a pro-fibrotic response in ASCs through IL1B and TGFB1 signaling, while anti-inflammatory M2 macrophages have limited effects. These findings shed light on cellular interactions in chronic wounds and provide important information for the potential therapeutic use of ASCs in human wound healing.

3.
Opt Express ; 31(18): 28946-28953, 2023 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-37710703

RESUMEN

We demonstrate transitional dimensionality of discrete diffraction in radial-elliptical photonic lattices. Varying the order, characteristic structure size, and ellipticity of the Mathieu beams used for the photonic lattices generation, we control the shape of discrete diffraction distribution over the combination of the radial direction with the circular, elliptic, or hyperbolic. We also investigate the transition from one-dimensional to two-dimensional discrete diffraction by varying the input probe beam position. The most pronounced discrete diffraction is observed along the crystal anisotropy direction.

4.
Cells ; 12(2)2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36672272

RESUMEN

Unfavorable clinical outcomes mean that cancer researchers must attempt to develop novel therapeutic strategies to overcome therapeutic resistance in patients with HNSCC. Recently, ferroptosis was shown to be a promising pathway possessing druggable targets, such as xCT (SLC7A11). Unfortunately, little is known about the molecular mechanisms underlying the susceptibility of HNSCC cells to ferroptosis. The goal of this study was to determine whether HNSCC cells with activated Erk1/2 are vulnerable to ferroptosis induction. Our results have shown that xCT (SLC7A11) was overexpressed in malignant tissues obtained from the patients with HNSCC, whereas normal mucosa demonstrated weak expression of the protein. In order to investigate the role of Erk1/2 in the decrease in cell viability caused by erastin, xCT-overexpressing FaDu and SCC25 HNSCC cells were used. The ravoxertinib-dependent inhibition of Erk1/2 signaling led to the decrease in erastin efficacy due to the effect on ROS production and the upregulation of ROS scavengers SOD1 and SOD2, resulting in repressed lipid peroxidation. Therefore, it was concluded that the erastin-dependent activation of ferroptosis seems to be a promising approach which can be further developed as an additional strategy for the treatment of HNSCC. As ferroptosis induction via erastin is strongly dependent on the expression of Erk1/2, this MAP kinase can be considered as a predictor for cancer cells' response to erastin.


Asunto(s)
Ferroptosis , Neoplasias de Cabeza y Cuello , Humanos , Carcinoma de Células Escamosas de Cabeza y Cuello , Especies Reactivas de Oxígeno/metabolismo , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/genética
5.
Magn Reson Med ; 89(4): 1314-1322, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36573435

RESUMEN

PURPOSE: Acetylcarnitine can be assessed in vivo using proton MRS (1 H-MRS) with long TEs and this has been previously applied successfully in muscle. The aim of this study was to evaluate a 1 H-MRS technique for liver acetylcarnitine quantification in healthy humans before and after l-carnitine supplementation. METHOD: Baseline acetylcarnitine levels were quantified using a STEAM sequence with prolonged TE in 15 healthy adults. Using STEAM with four different TEs was evaluated in phantoms. To assess reproducibility of the measurements, five of the participants had repeated 1 H-MRS without receiving l-carnitine supplementation. To determine if liver acetylcarnitine could be changed after l-carnitine supplementation, acetylcarnitine was quantified 2 h after intravenous l-carnitine supplementation (50 mg/kg body weight) in the other 10 participants. Hepatic lipids were also quantified from the 1 H-MRS spectra. RESULTS: There was good separation between the acetylcarnitine and fat in the phantoms using TE = 100 ms. Hepatic acetylcarnitine levels were reproducible (coefficient of reproducibility = 0.049%) and there was a significant (p < 0.001) increase in the relative abundance after a single supplementation of l-carnitine. Hepatic allylic, methyl, and methylene peaks were not altered by l-carnitine supplementation in healthy volunteers. CONCLUSION: Our results demonstrate that our 1 H-MRS technique could be used to measure acetylcarnitine in the liver and detect changes following intravenous supplementation in healthy adults despite the presence of lipids. Our techniques should be explored further in the study of fatty liver disease, where acetylcarnitine is suggested to be altered due to hepatic inflexibilities.


Asunto(s)
Acetilcarnitina , Carnitina , Adulto , Humanos , Reproducibilidad de los Resultados , Músculo Esquelético , Hígado/diagnóstico por imagen , Suplementos Dietéticos , Lípidos
6.
Medicina (Kaunas) ; 58(9)2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-36143827

RESUMEN

In children, the incidence of Legionnaires' disease (LD) is unknown, hospital-acquired LD is associated with clinical risk factors and environmental risk, and children with cell-mediated immune deficiency are at high risk of infection. Both newborns were born in the same delivery room; stayed in the same hospital room where they were cared for, bathed, and breastfed; were male; were born on time, with normal birth weight, and with high Apgar score at birth; and survived this severe infection (L. pneumophila, serogroup 2-15) but with different clinical courses. In neonate 1, bleeding in the brain, thrombosis of deep pelvic veins, and necrosis of the lungs, which left behind cystic and cavernous changes in the lungs, were found, while neonate 2 suffered from pneumonia alone. The only difference in risk factors for LD between these two newborns is the number of days of illness until the start of azithromycin treatment (sixth versus the third day of illness). We suggest that a change in the guidelines for diagnosing and treating community-acquired pneumonia and hospital-acquired pneumonia in newborns is needed in terms of mandatory routine testing for Legionella pneumophila. Early initiation of macrolide therapy is crucial for the outcome of LD in the newborn.


Asunto(s)
Infecciones Comunitarias Adquiridas , Legionella pneumophila , Enfermedad de los Legionarios , Azitromicina/uso terapéutico , Niño , Infecciones Comunitarias Adquiridas/diagnóstico , Infecciones Comunitarias Adquiridas/tratamiento farmacológico , Infecciones Comunitarias Adquiridas/epidemiología , Femenino , Maternidades , Humanos , Recién Nacido , Enfermedad de los Legionarios/diagnóstico , Enfermedad de los Legionarios/tratamiento farmacológico , Enfermedad de los Legionarios/epidemiología , Masculino , Embarazo
7.
Sci Rep ; 12(1): 13255, 2022 08 02.
Artículo en Inglés | MEDLINE | ID: mdl-35918485

RESUMEN

Mitochondrial dysfunction promotes cancer aggressiveness, metastasis, and resistance to therapy. Similar traits are associated with epithelial mesenchymal transition (EMT). We questioned whether mitochondrial dysfunction induces EMT in head and neck cancer (HNC) cell lines. We induced mitochondrial dysfunction in four HNC cell lines with carbonyl cyanide-4(trifluoromethoxy)phenylhydrazone (FCCP), a mitochondrial electron transport chain uncoupling agent, and oligomycin, a mitochondrial ATP synthase inhibitor. Extracellular flux analyses and expression of the cystine/glutamate antiporter system xc (xCT) served to confirm mitochondrial dysfunction. Expression of the EMT-related transcription factor SNAI2, the mesenchymal marker vimentin and vimentin/cytokeratin double positivity served to detect EMT. In addition, holotomographic microscopy was used to search for morphological features of EMT. Extracellular flux analysis and xCT expression confirmed that FCCP/oligomycin induced mitochondrial dysfunction in all cell lines. Across the four cell lines, mitochondrial dysfunction resulted in an increase in relative SNAI2 expression from 8.5 ± 0.8 to 12.0 ± 1.1 (mean ± SEM; p = 0.007). This effect was predominantly caused by the CAL 27 cell line (increase from 2.2 ± 0.4 to 5.5 ± 1.0; p < 0.001). Similarly, only in CAL 27 cells vimentin expression increased from 2.2 ± 0.5 × 10-3 to 33.2 ± 10.2 × 10-3 (p = 0.002) and vimentin/cytokeratin double positive cells increased from 34.7 ± 5.1 to 67.5 ± 9.8% (p = 0.003), while the other 3 cell lines did not respond with EMT (all p > 0.1). Across all cell lines, FCCP/oligomycin had no effect on EMT characteristics in holotomographic microscopy. Mitochondrial dysfunction induced EMT in 1 of 4 HNC cell lines. Given the heterogeneity of HNC, mitochondrial dysfunction may be sporadically induced by EMT, but EMT does not explain the tumor promoting effects of mitochondrial dysfunction in general.


Asunto(s)
Transición Epitelial-Mesenquimal , Neoplasias de Cabeza y Cuello , Cadherinas/metabolismo , Carbonil Cianuro p-Trifluorometoxifenil Hidrazona/farmacología , Línea Celular Tumoral , Humanos , Queratinas , Mitocondrias/metabolismo , Oligomicinas/farmacología , Vimentina/metabolismo
8.
Open Med (Wars) ; 17(1): 1275-1281, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35892079

RESUMEN

This study aimed to provide additional information on the influence of perinatal factors on fecal (f)-calprotectin values in preterm infants. Calprotectin was determined from the first spontaneous stool (analyzed on the Alegria device by using the enzyme-linked immunosorbent assay [ELISA] method) obtained from neonates at a mean age of 3.41 ± 2.44 days of life. We analyzed 114 subjects who had a body weight of 1847.67 ± 418.6 g and were born at a gestational age of 32.6 ± 2.43 weeks, without intestinal and other congenital anomalies or any diseases other than those related to premature birth. The values of f-calprotectin are in a positive correlation with female subjects, intrauterine growth restriction, significant ductus arteriosus, enteral feeding intolerance, postnatal prolonged use of broad-spectrum antibiotics, and values ​​of bicarbonates (analyzed in a sample of capillary arterial blood). Measurement of f-calprotectin in the first 7 days after birth can help to early detect the intestinal distress or early staging of necrotizing enterocolitis in premature infants.

10.
Opt Express ; 30(5): 7210-7224, 2022 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-35299488

RESUMEN

We introduce numerical modeling of two different methods for the deterministic randomization of two-dimensional aperiodic photonic lattices based on Mathieu beams, optically induced in a photorefractive media. For both methods we compare light transport and localization in such lattices along the propagation, for various disorder strengths. A disorder-enhanced light transport is observed for all disorder strengths. With increasing disorder strength light transport becomes diffusive-like and with further increase of disorder strength the Anderson localization is observed. This trend is more noticeable for longer propagation distances. The influence of input lattice intensity on the localization effects is studied. The difference in light transport between two randomization methods is attributed to various levels of input lattice intensity. We observe more pronounced localization for one of the methods. Localization lengths differ along different directions, due to the crystal and lattice anisotropy. We analyze localization effects comparing uniform and on-site probe beam excitation positions and different probe beam widths.

11.
Opt Lett ; 47(3): 702-705, 2022 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-35103712

RESUMEN

Complex optical systems such as deterministic aperiodic Mathieu lattices are known to hinder light diffraction in a manner comparable to randomized optical systems. We systematically incorporate randomness in our complex optical system, measuring its relative contribution of randomness, to understand the relationship between randomness and complexity. We introduce an experimental method for the realization of disordered aperiodic Mathieu lattices with numerically controlled disorder degree. Added disorder always enhances light transport. For lower disorder degrees, we observe diffusive-like transport, and in the range of highest light transport, we detect Anderson localization. With further increase of disorder degree, light transport is slowly decreasing and localization length decreases indicating more pronounced Anderson localization. Numerical investigation at longer propagation distances indicates that the threshold of Anderson localization detection is shifted to lower disorder degrees.

12.
Exp Cell Res ; 414(1): 113084, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35219646

RESUMEN

Epithelial to mesenchymal transition (EMT) describes a process where epithelial tumor cells acquire mesenchymal characteristics. EMT often correlates with invasion and an increased cell migration potential by losing cellular polarity and cell-cell junctions. It is mainly induced by tumor-microenvironment factors, such as TGF-beta 1 and IL-6, which activate the increased expression of the EMT-transcription factor (TF) Slug. We previously reported the Slug/Krüppel-like factor 4 (KLF4) switch in EMT in HNSCC, and found, that in human papilloma virus (HPV)-negative HNSCC Slug gene expression was significant higher represented, than in HPV-positive HNSCC. The purpose of this study was to investigate the impact of KLF4 and Slug on the regulation of the cadherin switch and on the EMT phenotype. Gene expression of KLF4 positive correlated with E-cadherin in 71 head and neck squamous cell carcinoma (HNSCC) patient tissue samples, which we also confirmed by the investigation of the Cancer Genome Atlas database (TCGA). HPV-transcripts contributed to stabilization of KLF4 at protein level, and simultaneously upregulated E-cadherin. Furthermore, ectopic KLF4 overexpression was associated with epithelial gene expression by induction of E-cadherin, ß-catenin and 70-kDa heat shock protein (HSP-70). The presence of HSP-70 ensures the membranous localization of E-cadherin, therefore, the ability of cells to form cadherin/catenin complexes and cellular linkages. In conclusion, KLF4 is a major regulator of the epithelial cadherin-adhesion in HNSCC.


Asunto(s)
Carcinoma de Células Escamosas , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Cadherinas/metabolismo , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Movimiento Celular/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/genética , Humanos , Infecciones por Papillomavirus/genética , Factores de Transcripción de la Familia Snail/genética , Factores de Transcripción de la Familia Snail/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Microambiente Tumoral
14.
Radiol Oncol ; 55(3): 305-316, 2021 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-33939900

RESUMEN

BACKGROUND: Statins, small molecular 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors, are widely used to lower cholesterol levels in lipid-metabolism disorders. Recent preclinical and clinical studies have shown that statins exert beneficial effects in the management of breast cancer by increasing recurrence free survival. Unfortunately, the underlying mechanisms remain elusive. MATERIALS AND METHODS: Simvastatin, one of the most widely prescribed lipophilic statins was utilized to investigate potential radiosensitizing effects and an impact on cell survival and migration in radioresistant breast cancer cell lines. RESULTS: Compared to parental cell counterparts, radioresistant MDA-MB-231-RR, T47D-RR andAu565-RR cells were characterized by upregulation of 3-hydroxy-3-methylglutharyl-coenzyme A reductase (HMGCR) expression accompanied by epithelial-to-mesenchymal transition (EMT) activation. Radioresistant breast cancer cells can be killed by simvastatin via mobilizing of a variety of pathways involved in apoptosis and autophagy. In the presence of simvastatin migratory abilities and vimentin expression is diminished while E-cadherin expression is increased. CONCLUSIONS: The present study suggests that simvastatin may effectively eradicate radioresistant breast carcinoma cells and diminish their mesenchymal phenotypes.


Asunto(s)
Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Tolerancia a Radiación/efectos de los fármacos , Fármacos Sensibilizantes a Radiaciones/farmacología , Simvastatina/farmacología , Muerte Celular Autofágica/efectos de los fármacos , Cadherinas/metabolismo , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Transición Epitelial-Mesenquimal , Femenino , Humanos , Hidroximetilglutaril-CoA Reductasas/metabolismo , Regulación hacia Arriba
15.
Cells ; 10(3)2021 03 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802627

RESUMEN

Epithelial to mesenchymal transition (EMT) is clinically relevant in head and neck squamous cell carcinoma (HNSCC). We hypothesized that EMT-transcription factors (EMT-TFs) and an anti-EMT factor, Krüppel-like-factor-4 (KLF4) regulate EMT in HNSCC. Ten control mucosa and 37 HNSCC tissue samples and three HNSCC cell lines were included for investigation of EMT-TFs, KLF4 and vimentin at mRNA and protein levels. Slug gene expression was significantly higher, whereas, KLF4 gene expression was significantly lower in HNSCC than in normal mucosa. In the majority of HNSCC samples, there was a significant negative correlation between KLF4 and Slug gene expression. Slug gene expression was significantly higher in human papilloma virus (HPV) negative HNSCC, and in tumor samples with irregular p53 gene sequence. Transforming-growth-factor-beta-1 (TGF- ß1) contributed to downregulation of KLF4 and upregulation of Slug. Two possible regulatory pathways could be suggested: (1) EMT-factors induced pathway, where TGF-ß1 induced Slug together with vimentin, and KLF4 was down regulated at the same time; (2) p53 mutations contributed to upregulation and stabilization of Slug, where also KLF4 could co-exist with EMT-TFs.


Asunto(s)
Neoplasias de Cabeza y Cuello/genética , Factores de Transcripción de Tipo Kruppel/genética , Proteínas Nucleares/genética , Factores de Transcripción de la Familia Snail/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Proteína p53 Supresora de Tumor/genética , Proteína 1 Relacionada con Twist/genética , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Transición Epitelial-Mesenquimal/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Neoplasias de Cabeza y Cuello/metabolismo , Neoplasias de Cabeza y Cuello/mortalidad , Neoplasias de Cabeza y Cuello/patología , Humanos , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Proteínas Nucleares/metabolismo , Transducción de Señal , Factores de Transcripción de la Familia Snail/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo , Carcinoma de Células Escamosas de Cabeza y Cuello/mortalidad , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Análisis de Supervivencia , Factor de Crecimiento Transformador beta1/genética , Factor de Crecimiento Transformador beta1/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Proteína 1 Relacionada con Twist/metabolismo , Vimentina/genética , Vimentina/metabolismo , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/genética , Homeobox 1 de Unión a la E-Box con Dedos de Zinc/metabolismo
16.
Metabolites ; 11(3)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806953

RESUMEN

The diabetic heart is energetically and metabolically abnormal, with increased fatty acid oxidation and decreased glucose oxidation. One factor contributing to the metabolic dysfunction in diabetes may be abnormal handling of acetyl and acyl groups by the mitochondria. L-carnitine is responsible for their transfer across the mitochondrial membrane, therefore, supplementation with L-carnitine may provide a route to improve the metabolic state of the diabetic heart. The primary aim of this study was to use hyperpolarized magnetic resonance imaging (MRI) to investigate the effects of L-carnitine supplementation on the in vivo metabolism of [1-13C]pyruvate in diabetes. Male Wistar rats were injected with either vehicle or streptozotocin (55 mg/kg) to induce type-1 diabetes. Three weeks of daily i.p. treatment with either saline or L-carnitine (3 g/kg/day) was subsequently undertaken. In vivo cardiac function and metabolism were assessed with CINE and hyperpolarized MRI, respectively. L-carnitine supplementation prevented the progression of hyperglycemia, which was observed in untreated streptozotocin injected animals and led to reductions in plasma triglyceride and ß-hydroxybutyrate concentrations. Hyperpolarized MRI revealed that L-carnitine treatment elevated pyruvate dehydrogenase flux by 3-fold in the diabetic animals, potentially through increased buffering of excess acetyl-CoA units in the mitochondria. Improved functional recovery following ischemia was also observed in the L-carnitine treated diabetic animals.

17.
NMR Biomed ; 34(4): e4471, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33458907

RESUMEN

The diabetic heart has a decreased ability to metabolize glucose. The anti-ischemic drug meldonium may provide a route to counteract this by reducing l-carnitine levels, resulting in improved cardiac glucose utilization. Therefore, the aim of this study was to use the novel technique of hyperpolarized magnetic resonance to investigate the in vivo effects of treatment with meldonium on cardiac metabolism and function in control and diabetic rats. Thirty-six male Wistar rats were injected either with vehicle, or with streptozotocin (55 mg/kg) to induce a model of type 1 diabetes. Daily treatment with either saline or meldonium (100 mg/kg/day) was undertaken for three weeks. in vivo cardiac function and metabolism were assessed with CINE MRI and hyperpolarized magnetic resonance respectively. Isolated perfused hearts were challenged with low-flow ischemia/reperfusion to assess the impact of meldonium on post-ischemic recovery. Meldonium had no significant effect on blood glucose concentrations or on baseline cardiac function. However, hyperpolarized magnetic resonance revealed that meldonium treatment elevated pyruvate dehydrogenase flux by 3.1-fold and 1.2-fold in diabetic and control animals, respectively, suggesting an increase in cardiac glucose oxidation. Hyperpolarized magnetic resonance further demonstrated that meldonium reduced the normalized acetylcarnitine signal by 2.1-fold in both diabetic and control animals. The increase in pyruvate dehydrogenase flux in vivo was accompanied by an improvement in post-ischemic function ex vivo, as meldonium elevated the rate pressure product by 1.3-fold and 1.5-fold in the control and diabetic animals, respectively. In conclusion, meldonium improves in vivo pyruvate dehydrogenase flux in the diabetic heart, contributing to improved cardiac recovery after ischemia.


Asunto(s)
Diabetes Mellitus Experimental/complicaciones , Espectroscopía de Resonancia Magnética/métodos , Metilhidrazinas/uso terapéutico , Isquemia Miocárdica/tratamiento farmacológico , Complejo Piruvato Deshidrogenasa/fisiología , Animales , Glucosa/metabolismo , Masculino , Metabolómica , Metilhidrazinas/farmacología , Isquemia Miocárdica/fisiopatología , Miocardio/metabolismo , Ratas , Ratas Wistar , Estreptozocina
18.
Comput Methods Programs Biomed ; 201: 105933, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33517234

RESUMEN

BACKGROUND AND OBJECTIVE: Mathematical modeling and computational simulations of arterial blood flow network can offer an insilico platform for both diagnostics and therapeutic phases of patients that suffer from cardiac diseases. These models are normally complex and involve many unknown parameters. For physiological relevance, these parameters should be optimized using in-vivo human/animal data sets. The main goal of this work is to develop an efficient, yet an accurate optimization algorithm to compute parameters in the arterial blood flow models. METHODS: The particle swarm optimization (PSO) method is proposed herein for the first time, as an accurate algorithm that applies to computing parameters in the Windkessel type model of blood flow in the arterial system. We begin by defining a 6-element Windkessel (WK6) arterial flow model, which is then implemented and validated using multiple flow rate and aortic pressure measurements obtained from different subjects including dogs, pigs and humans. The parameters in the model are obtained using the PSO technique which minimizes the pressure root mean square (P-RMS) error between the computed and the measured aortic pressure waveform. RESULTS: Model parameters obtained using the proposed PSO method were able to recover the pressure waveform in the aorta during the cardiac cycle for both healthy and diseased species (animals/humans). The PSO method provides an accurate approach to solve this challenging multi-dimensional parameter identification problem. The results obtained by PSO algorithm was compared with the classical gradient-based, namely the non-linear square fit (NLSF) algorithm. CONCLUSIONS: The results indicate that the PSO method offers alternative and accurate method to find optimal physiological parameters involved in the Windkessel model for the study of arterial blood flow network. The PSO method has performed better than the NLSF approach as depicted from the P-RMS calculations. Finally, we believe that the PSO method offers a great potential and could be used for many other biomedicine optimization problems.


Asunto(s)
Algoritmos , Modelos Teóricos , Animales , Aorta , Perros , Hemodinámica , Humanos , Porcinos
19.
Front Physiol ; 12: 782745, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35069242

RESUMEN

Doxorubicin (DOX) is a successful chemotherapeutic widely used for the treatment of a range of cancers. However, DOX can have serious side-effects, with cardiotoxicity and hepatotoxicity being the most common events. Oxidative stress and changes in metabolism and bioenergetics are thought to be at the core of these toxicities. We have previously shown in a clinically-relevant rat model that a low DOX dose of 2 mg kg-1 week-1 for 6 weeks does not lead to cardiac functional decline or changes in cardiac carbohydrate metabolism, assessed with hyperpolarized [1-13C]pyruvate magnetic resonance spectroscopy (MRS). We now set out to assess whether there are any signs of liver damage or altered liver metabolism using this subclinical model. We found no increase in plasma alanine aminotransferase (ALT) activity, a measure of liver damage, following DOX treatment in rats at any time point. We also saw no changes in liver carbohydrate metabolism, using hyperpolarized [1-13C]pyruvate MRS. However, using metabolomic analysis of liver metabolite extracts at the final time point, we found an increase in most acyl-carnitine species as well as increases in high energy phosphates, citrate and markers of oxidative stress. This may indicate early signs of steatohepatitis, with increased and decompensated fatty acid uptake and oxidation, leading to oxidative stress.

20.
MAGMA ; 34(1): 49-56, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32910316

RESUMEN

OBJECTIVES: To enhance detection of the products of hyperpolarized [2-13C]dihydroxyacetone metabolism for assessment of three metabolic pathways in the liver in vivo. Hyperpolarized [2-13C]DHAc emerged as a promising substrate to follow gluconeogenesis, glycolysis and the glycerol pathways. However, the use of [2-13C]DHAc in vivo has not taken off because (i) the chemical shift range of [2-13C]DHAc and its metabolic products span over 144 ppm, and (ii) 1H decoupling is required to increase spectral resolution and sensitivity. While these issues are trivial for high-field vertical-bore NMR spectrometers, horizontal-bore small-animal MR scanners are seldom equipped for such experiments. METHODS: Real-time hepatic metabolism of three fed mice was probed by 1H-decoupled 13C-MR following injection of hyperpolarized [2-13C]DHAc. The spectra of [2-13C]DHAc and its metabolic products were acquired in a 7 T small-animal MR scanner using three purpose-designed spectral-spatial radiofrequency pulses that excited a spatial bandwidth of 8 mm with varying spectral bandwidths and central frequencies (chemical shifts). RESULTS: The metabolic products detected in vivo include glycerol 3-phosphate, glycerol, phosphoenolpyruvate, lactate, alanine, glyceraldehyde 3-phosphate and glucose 6-phosphate. The metabolite-to-substrate ratios were comparable to those reported previously in perfused liver. DISCUSSION: Three metabolic pathways can be probed simultaneously in the mouse liver in vivo, in real time,  using hyperpolarized DHAc.


Asunto(s)
Dihidroxiacetona/química , Animales , Isótopos de Carbono , Gluconeogénesis , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Ratones , Protones
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