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1.
Circulation ; 145(12): 916-933, 2022 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-35175782

RESUMEN

BACKGROUND: Pulmonary hypertension (PH) is a life-threatening disease, characterized by excessive pulmonary vascular remodeling, leading to elevated pulmonary arterial pressure and right heart hypertrophy. PH can be caused by chronic hypoxia, leading to hyper-proliferation of pulmonary arterial smooth muscle cells (PASMCs) and apoptosis-resistant pulmonary microvascular endothelial cells (PMVECs). On reexposure to normoxia, chronic hypoxia-induced PH in mice is reversible. In this study, the authors aim to identify novel candidate genes involved in pulmonary vascular remodeling specifically in the pulmonary vasculature. METHODS: After microarray analysis, the authors assessed the role of SPARC (secreted protein acidic and rich in cysteine) in PH using lung tissue from idiopathic pulmonary arterial hypertension (IPAH) patients, as well as from chronically hypoxic mice. In vitro studies were conducted in primary human PASMCs and PMVECs. In vivo function of SPARC was proven in chronic hypoxia-induced PH in mice by using an adeno-associated virus-mediated Sparc knockdown approach. RESULTS: C57BL/6J mice were exposed to normoxia, chronic hypoxia, or chronic hypoxia with subsequent reexposure to normoxia for different time points. Microarray analysis of the pulmonary vascular compartment after laser microdissection identified Sparc as one of the genes downregulated at all reoxygenation time points investigated. Intriguingly, SPARC was vice versa upregulated in lungs during development of hypoxia-induced PH in mice as well as in IPAH, although SPARC plasma levels were not elevated in PH. TGF-ß1 (transforming growth factor ß1) or HIF2A (hypoxia-inducible factor 2A) signaling pathways induced SPARC expression in human PASMCs. In loss of function studies, SPARC silencing enhanced apoptosis and reduced proliferation. In gain of function studies, elevated SPARC levels induced PASMCs, but not PMVECs, proliferation. Coculture and conditioned medium experiments revealed that PMVECs-secreted SPARC acts as a paracrine factor triggering PASMCs proliferation. Contrary to the authors' expectations, in vivo congenital Sparc knockout mice were not protected from hypoxia-induced PH, most probably because of counter-regulatory proproliferative signaling. However, adeno-associated virus-mediated Sparc knockdown in adult mice significantly improved hemodynamic and cardiac function in PH mice. CONCLUSIONS: This study provides evidence for the involvement of SPARC in the pathogenesis of human PH and chronic hypoxia-induced PH in mice, most likely by affecting vascular cell function.


Asunto(s)
Hipertensión Pulmonar , Animales , Proliferación Celular , Células Cultivadas , Células Endoteliales/metabolismo , Hipertensión Pulmonar Primaria Familiar/metabolismo , Humanos , Hipertensión Pulmonar/patología , Hipoxia/metabolismo , Ratones , Ratones Endogámicos C57BL , Miocitos del Músculo Liso/metabolismo , Osteonectina/genética , Arteria Pulmonar , Remodelación Vascular/genética
2.
Emerg Infect Dis ; 29(4): 843-845, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36958036

RESUMEN

Thelazia callipaeda is a zoonotic vector-borne nematode that infects and causes eye disease among a wide range of domestic and wild mammals, including humans. We describe an unusual case of reinfection by this nematode in Serbia and call for a focus on preventive measures in endemic areas.


Asunto(s)
Enfermedades de los Perros , Oftalmopatías , Infecciones por Spirurida , Thelazioidea , Animales , Humanos , Perros , Reinfección , Infecciones por Spirurida/epidemiología , Infecciones por Spirurida/prevención & control , Infecciones por Spirurida/veterinaria , Serbia , Enfermedades de los Perros/epidemiología , Mamíferos
3.
Cells Tissues Organs ; 212(3): 203-214, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35605590

RESUMEN

This study aimed to morphometrically examine the development of glomeruli and tubules in the kidney cortex of human foetuses at different gestational ages (GAs). We also investigated the expression of the proliferation marker Ki-67 and apoptosis-related markers Bcl-2 and Bax during nephrogenesis using immunohistochemistry. Kidney samples from 38 human foetuses of both sexes with GA ranging from 13 to 40 weeks were analysed. The samples were divided into 7 groups based on GA, each corresponding to 1 lunar month. Foetal kidneys showed a spatiotemporal gradient of nephron differentiation with the transient stages of nephron anlage located in the nephrogenic zone and immature nephrons located in the subjacent maturation zone. In the inner cortex, nephrons establish the morphological characteristics of definitive nephrons. The average area, perimeter, and Feret's diameter of the glomeruli formed within the kidney cortex gradually decreased up to a period of 29-32 weeks of gestation and subsequently increased until a period of 37-40 weeks. There was a weak negative correlation with GA. In contrast, the areal density of glomeruli increased up to a period of 21-24 weeks and then gradually decreased until a period of 37-40 weeks, showing a moderate negative correlation with GA. The average area of renal tubules slightly decreased until a period of 21-24 weeks of gestation and then gradually increased until a period of 36-40 weeks, showing a moderate positive correlation with GA. The average areal density of renal tubules increased significantly until a period of 21-24 weeks of gestation, remained relatively constant until a period of 33-36 weeks, and then increased significantly at 36-40 weeks. There was a strong positive correlation with GA. Our results showed that Ki-67 was expressed in numerous cells of the metanephric mesenchyme, pretubular aggregates, renal vesicles, comma-shaped bodies, and early S-shaped bodies. During subsequent development and the spatial expansion of nephrons towards the mature zone, the expression of Ki-67 was markedly reduced. Similarly, Bcl-2 was strongly expressed in induced nephrogenic progenitor cells, pretubular aggregates, renal vesicles, and comma-shaped bodies. As vascularisation and maturation of the nephron proceeded, Bcl-2 staining became less intense and limited to the parietal layer of the Bowman's capsule and renal tubules. Weak Bax expression was observed in individual scattered cells within segments of the nephrons at all developmental stages. In the mature zone, more intense Bax staining was observed in the renal tubules.


Asunto(s)
Enfermedades Renales , Riñón , Masculino , Femenino , Humanos , Proteína X Asociada a bcl-2/metabolismo , Antígeno Ki-67/metabolismo , Nefronas , Glomérulos Renales , Enfermedades Renales/metabolismo , Feto , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo
4.
Sensors (Basel) ; 23(24)2023 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-38139724

RESUMEN

Monitoring heart electrical activity is an effective way of detecting existing and developing conditions. This is usually performed as a non-invasive test using a network of up to 12 sensors (electrodes) on the chest and limbs to create an electrocardiogram (ECG). By visually observing these readings, experienced professionals can make accurate diagnoses and, if needed, request further testing. However, the training and experience needed to make accurate diagnoses are significant. This work explores the potential of recurrent neural networks for anomaly detection in ECG readings. Furthermore, to attain the best possible performance for these networks, training parameters, and network architectures are optimized using a modified version of the well-established particle swarm optimization algorithm. The performance of the optimized models is compared to models created by other contemporary optimizers, and the results show significant potential for real-world applications. Further analyses are carried out on the best-performing models to determine feature importance.


Asunto(s)
Algoritmos , Redes Neurales de la Computación , Electrocardiografía/métodos
5.
Medicina (Kaunas) ; 59(3)2023 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-36984490

RESUMEN

Background and objectives: In patients with colorectal cancer (CRC), heterogeneous expression of Mismatch repair (MMR) proteins can manifest itself in several different forms and is not such a rare phenomenon. Therefore, it is very important to recognize the nuclear expression of MMR proteins of different MMR status in order to avoid false positive or false negative results. The aim of this study was to determine the frequency and distribution of heterogeneous expression of MMR proteins in patients with stages II and III of the disease as well as its association with clinical, demographic and pathological characteristics of CRC in relation to proficient and deficient expression of MMR proteins. Material and Methods: The study included 104 cases of colorectal cancer obtained from surgical colectomy material in stages II and III of the disease. Results: From a total of 104 patients with colorectal cancer, immunohistochemical analysis of the expression of all four MMR proteins showed that heterogeneous expression of MMR proteins (as well as deficient immunoreactivity of tumor cells) was present in 12 cases, while proficient expression of MMR proteins was detected in 80 tumors. Conclusions: Our study showed that the only independent predictors of the loss of MMR protein expression were younger patient age and right-sided anatomical location of the tumor. The study also established the existence of heterogeneous expression of MMR proteins in a non-negligible percentage of CRCs (11.5%), where heterogeneous nuclear expression of MMR proteins was described in several different forms.


Asunto(s)
Neoplasias Colorrectales , Humanos , Neoplasias Colorrectales/patología , Estadificación de Neoplasias , Proteínas Adaptadoras Transductoras de Señales , Homólogo 1 de la Proteína MutL/metabolismo
6.
Sensors (Basel) ; 22(5)2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35270856

RESUMEN

We live in a period when smart devices gather a large amount of data from a variety of sensors and it is often the case that decisions are taken based on them in a more or less autonomous manner. Still, many of the inputs do not prove to be essential in the decision-making process; hence, it is of utmost importance to find the means of eliminating the noise and concentrating on the most influential attributes. In this sense, we put forward a method based on the swarm intelligence paradigm for extracting the most important features from several datasets. The thematic of this paper is a novel implementation of an algorithm from the swarm intelligence branch of the machine learning domain for improving feature selection. The combination of machine learning with the metaheuristic approaches has recently created a new branch of artificial intelligence called learnheuristics. This approach benefits both from the capability of feature selection to find the solutions that most impact on accuracy and performance, as well as the well known characteristic of swarm intelligence algorithms to efficiently comb through a large search space of solutions. The latter is used as a wrapper method in feature selection and the improvements are significant. In this paper, a modified version of the salp swarm algorithm for feature selection is proposed. This solution is verified by 21 datasets with the classification model of K-nearest neighborhoods. Furthermore, the performance of the algorithm is compared to the best algorithms with the same test setup resulting in better number of features and classification accuracy for the proposed solution. Therefore, the proposed method tackles feature selection and demonstrates its success with many benchmark datasets.


Asunto(s)
Algoritmos , Inteligencia Artificial , Aprendizaje Automático
7.
Int J Mol Sci ; 21(23)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33265921

RESUMEN

Although the response of the right ventricle (RV) to the increased afterload is an important determinant of the patient outcome, very little is known about the underlying mechanisms. Mast cells have been implicated in the pathogenesis of left ventricular maladaptive remodeling and failure. However, the role of mast cells in RV remodeling remains unexplored. We subjected mast cell-deficient WBB6F1-KitW/W-v (KitW/KitW-v) mice and their mast cell-sufficient littermate controls (MC+/+) to pulmonary artery banding (PAB). PAB led to RV dilatation, extensive myocardial fibrosis, and RV dysfunction in MC+/+ mice. In PAB KitW/KitW-v mice, RV remodeling was characterized by minimal RV chamber dilatation and preserved RV function. We further administered to C57Bl/6J mice either placebo or cromolyn treatment starting from day 1 or 7 days after PAB surgery to test whether mast cells stabilizing drugs can prevent or reverse maladaptive RV remodeling. Both preventive and therapeutic cromolyn applications significantly attenuated RV dilatation and improved RV function. Our study establishes a previously undescribed role of mast cells in pressure overload-induced adverse RV remodeling. Mast cells may thus represent an interesting target for the development of a new therapeutic approach directed specifically at the heart.


Asunto(s)
Mastocitos/metabolismo , Mastocitos/patología , Presión , Remodelación Ventricular/genética , Animales , Biomarcadores/metabolismo , Cromolin Sódico/administración & dosificación , Cromolin Sódico/farmacología , Fibrosis , Regulación de la Expresión Génica/efectos de los fármacos , Ventrículos Cardíacos/efectos de los fármacos , Ventrículos Cardíacos/patología , Hipertrofia , Inflamación/patología , Mediadores de Inflamación/metabolismo , Masculino , Mastocitos/efectos de los fármacos , Ratones Endogámicos C57BL , Miocitos Cardíacos/efectos de los fármacos , Miocitos Cardíacos/patología , Remodelación Ventricular/efectos de los fármacos
8.
Medicina (Kaunas) ; 56(12)2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33302424

RESUMEN

Background and objectives: Deficient mismatch repair (MMR) status is associated with good prognosis but poor therapeutic response to adjuvant chemotherapy in patients with colorectal cancer. However, there are some opposed arguments considering therapeutic outcomes in patients with evidenced MMR deficiency in colorectal cancer. The aim of the study was the investigation of prognostic value and immunohistochemical analysis of the MMR-deficiency tumors. Materials and Methods: The study enrolled 104 patients with resected stage II and III colorectal cancer samples from the period 2018-2019. Results: The tumors with deficient MMR status were significantly associated with age up to 50 years and right-sided localization (p < 0.001). During the follow-up period of 22.43 ± 6.66 months, 21 patients (20.2%) died, whereas 14 patients (13.5%) had relapses. The loss of mutL homologue 1/postmeiotic segregation increased 2 (MLH1/PMS2) expression, compared to proficient MMR tumors, was associated with shorter disease-free survival in patients with lymphovascular invasion (p < 0.05), perineural invasion (p < 0.01), stage III (p < 0.05) and high-grade tumor (p < 0.05). Conclusions: This retrospective pilot study of a single-center cohort of patients with stage II and III colorectal cancer highlights the clinical importance of using immunohistochemistry (IHC) analysis as a guide for diagnostic algorithm in a country with limited resources, but with a high prevalence of colorectal carcinoma in the young patients. MMR-deficiency tumors compared with proficient MMR colorectal cancer was not shown to be a significant predictor of disease-free and overall survival.


Asunto(s)
Neoplasias Colorrectales , Recurrencia Local de Neoplasia , Neoplasias Encefálicas , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Humanos , Homólogo 1 de la Proteína MutL/genética , Estadificación de Neoplasias , Síndromes Neoplásicos Hereditarios , Proyectos Piloto , Pronóstico , Estudios Retrospectivos
9.
Medicina (Kaunas) ; 56(3)2020 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-32188043

RESUMEN

Background and objectives: Pulmonary hypertension (PH) is characterized by the vasoconstriction and abnormally proliferative vascular cells. The available allopathic treatment options for PH are still not able to cure the disease. Alternative medicine is becoming popular and drawing the attention of the general public and scientific communities. The entomogenous fungus Yarsagumba (Cordyceps sinensis) and its biologically active ingredient cordycepin may represent the therapeutic option for this incurable disease, owing to their anti-inflammatory, vasodilatory and anti-oxidative effects. Methods: In this study, we investigated whether Yarsagumba extract and cordycepin possess anti-proliferative and vasorelaxant properties in the context of PH, using 5-bromo-2'-deoxyuridine assay and isolated mice lungs, respectively. Results: Our results revealed that Yarsagumba extract and its bioactive compound cordycepin significantly attenuated the proliferation of human pulmonary artery smooth muscle cells derived from donor and PH subjects. In isolated murine lungs, only Yarsagumba extract, but not cordycepin, resulted in vasodilatation, indicating the probable existence of other bioactive metabolites present in Yarsagumba that may be responsible for this outcome. Conclusion: Future comprehensive in vivo and in vitro research is crucially needed to discover the profound mechanistic insights with regard to this promising therapeutic potency of Yarsagumba extract and to provide further evidence as to whether it can be used as a strategy for the treatment of PH.


Asunto(s)
Antifúngicos/farmacología , Materiales Biocompatibles/farmacología , Desoxiadenosinas/farmacología , Hipertensión Pulmonar/tratamiento farmacológico , Vasodilatadores/farmacología , Animales , Antifúngicos/administración & dosificación , Materiales Biocompatibles/administración & dosificación , Estudios de Casos y Controles , Proliferación Celular/efectos de los fármacos , Cordyceps/química , Cordyceps/metabolismo , Desoxiadenosinas/administración & dosificación , Humanos , Hipertensión Pulmonar/fisiopatología , Pulmón/irrigación sanguínea , Pulmón/fisiopatología , Ratones , Ratones Endogámicos C57BL , Músculo Liso Vascular/citología , Músculo Liso Vascular/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Placebos/administración & dosificación , Vasodilatadores/administración & dosificación
10.
Eur Respir J ; 53(6)2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30956210

RESUMEN

Chronic obstructive pulmonary disease (COPD), which comprises the phenotypes of chronic bronchitis and emphysema, is often associated with pulmonary hypertension (PH). However, currently, no approved therapy exists for PH-COPD. Signalling of the nitric oxide (NO)-cyclic guanosine monophosphate (cGMP) axis plays an important role in PH and COPD.We investigated the treatment effect of riociguat, which promotes the NO-cGMP pathway, in the mouse model of smoke-induced PH and emphysema in a curative approach, and retrospectively analysed the effect of riociguat treatment on PH in single patients with PH-COPD.In mice with established PH and emphysema (after 8 months of cigarette smoke exposure), riociguat treatment for another 3 months fully reversed PH. Moreover, histological hallmarks of emphysema were decreased. Microarray analysis revealed involvement of different signalling pathways, e.g. related to matrix metalloproteinases (MMPs). MMP activity was decreased in vivo by riociguat. In PH-COPD patients treated with riociguat (n=7), the pulmonary vascular resistance, airway resistance and circulating MMP levels decreased, while oxygenation at rest was not significantly changed.Riociguat may be beneficial for treatment of PH-COPD. Further long-term prospective studies are necessary to investigate the tolerability, efficacy on functional parameters and effect specifically on pulmonary emphysema in COPD patients.


Asunto(s)
GMP Cíclico/metabolismo , Hipertensión Pulmonar/tratamiento farmacológico , Óxido Nítrico/metabolismo , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Pirazoles/farmacología , Pirimidinas/farmacología , Animales , Modelos Animales de Enfermedad , Humanos , Hipertensión Pulmonar/etiología , Hipertensión Pulmonar/metabolismo , Pulmón/patología , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfisema Pulmonar/fisiopatología , Estudios Retrospectivos , Transducción de Señal , Guanilil Ciclasa Soluble/metabolismo , Investigación Biomédica Traslacional
11.
Medicina (Kaunas) ; 55(8)2019 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-31405154

RESUMEN

The currently used immunohistochemical approach in determining the estrogen receptor (ER) positivity of breast cancers (BCs) is inherently subjective and additionally limited by its semi-quantitative nature. The application of software in the analysis of digitized slide images may overcome some of these limitations. However, the utilization of such an approach requires that the entire staining procedure is standardized. BACKGROUND AND OBJECTIVES: We aimed to establish a procedure for the photometric and morphometric analysis of BC immunohistochemical parameters that can possibly be used for a diagnostic purpose that is in line with the current semi-quantitative scoring system. MATERIALS AND METHODS: Semi-quantitative analysis of ER-stained tissue sections was performed following the Allred scoring system guidelines. The quantitative analysis was performed in ImageJ software after color deconvolution. The quantitative analysis of 66 cases of invasive lobular BC included: Percent of ER-positive cells, average nuclear coloration intensity, and the quantitative ER score. The percent of ER-positive tumor cells was counted using a standard grid overlay, while optical density (0.0-1.0) was measured within each nucleus at the grid points. RESULTS: A statistical analysis revealed a significant positive correlation (r = 0.886, p < 0.001) between the subjective semi-quantitative and quantitative ER scores, with a large effect size (d = 3.8215). We observed strong statistically significant correlations between individual parameters of the total ER score, percentage of ER-positive nuclei, and color intensity, obtained by the two independent methods. CONCLUSIONS: Additionally, besides excluding subjectivity, the up to now unreported cases of 3 + 0, 4 + 0, and 5 + 0 Allred scores were detected only by the application of the proposed quantitative approach.


Asunto(s)
Neoplasias de la Mama/química , Neoplasias de la Mama/inmunología , Receptores de Estrógenos/análisis , Adulto , Femenino , Humanos , Inmunohistoquímica/métodos , Persona de Mediana Edad , Receptores de Estrógenos/inmunología , Proyectos de Investigación/tendencias
12.
Cells Tissues Organs ; 205(3): 164-177, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29949800

RESUMEN

In the absence of systematized data on the extracellular matrix components during prenatal liver development, the present study aimed to investigate the time of appearance and distribution of collagen types I, III, and IV and laminin. The study material included embryonic and fetal livers, aged 7-37 weeks, categorized into 3 trimesters. The material was stained using hematoxylin-eosin and immunohistochemistry methods for the identification of collagen I, III, and IV and laminin. Collagen I was detected near the end of the first trimester in the capsules and walls of interlobular veins. As the liver matures, collagen I is increasingly abundant in the capsules, portal area connective tissues, arterial walls, interlobular veins, sinusoids, and central veins. Collagen III and collagen IV appear in the middle of the first trimester in the capsules, portal areas, and walls of central veins, as well as the sinusoids particularly. In trimesters 2 and 3, these collagens are increasingly present in all the structures, but collagen IV is also present in nerve fibers. Laminin is sporadically present adjacent to the sinusoids in trimester 1, while in trimesters 2 and 3 this protein commonly appears in the walls of arteries and interlobular veins, in the basal membrane of bile ducts, and in nerve fibers. The contents of collagen I, III, and IV increase during prenatal development in the liver capsule, arterial and vein walls, sinusoids, and portal area. Laminin expression is consistent with that of the collagens with the exception that, within lobules, laminin disappears with liver maturation.


Asunto(s)
Colágeno/metabolismo , Desarrollo Embrionario , Laminina/metabolismo , Hígado/metabolismo , Feto/citología , Feto/metabolismo , Humanos , Hígado/embriología
13.
Pediatr Nephrol ; 33(5): 817-825, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29273971

RESUMEN

BACKGROUND: Human fetal kidney development is a complex and stepwise process. The number, shape, size and distribution of glomeruli provide important information on kidney organization. The aim of this study was to quantify glomerular developing forms during human fetal kidney development using stereological methods. METHODS: Kidney tissue specimens of 40 human fetuses with gestational ages ranging from 9 to 40 weeks were analyzed. Specimens were divided into eight groups based on gestational age, each corresponding to 1 lunar month. Stereological methods were used at the light microscopy level to estimate volume, surface and numerical density of the glomerular developing forms. RESULTS: During gestation, nephrogenesis continually advanced, and the number of nephrons increased. Volume, surface and numerical densities of vesicular forms and S-shaped bodies decreased gradually in parallel with gradual increases in estimated stereological parameters for vascularized glomeruli. Volume density and surface density of vascularized glomeruli increased gradually during fetal kidney development, and numerical density increased until the seventh lunar month. A relative decrease in vascularized glomeruli per unit volume of cortex occurred during the last 3 lunar months. Nephrogenesis began to taper off by 32 weeks and was completed by 36 weeks of gestation. The last sample in which we observed vesicles was from a fetus aged 32 weeks, and the last sample with S-shaped bodies was from a fetus aged 36 weeks. CONCLUSIONS: The present study is one of few quantitative studies conducted on human kidney development. Knowledge of normal human kidney morphogenesis during development could be important for future medical practice. Events occurring during fetal life may have significant consequences later in life.


Asunto(s)
Desarrollo Fetal/fisiología , Riñón/embriología , Organogénesis/fisiología , Femenino , Feto , Edad Gestacional , Humanos , Masculino , Embarazo
14.
Cells Tissues Organs ; 203(4): 243-257, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-27889769

RESUMEN

The endothelium of liver sinusoids in relation to the endothelium of other blood vessels has specific antigen expression similar to the endothelium of lymphatic vessels. Bearing in mind that there is no consensus as to the period or intensity of the expression of certain antigens in the endothelium of blood and lymphatic vessels in the liver, the aim of our study was to immunohistochemically investigate the dynamic patterns of the expression of CD31, CD34, D2-40, and LYVE-1 antigens during liver development and in adulthood on paraffin tissue sections of human livers of 4 embryos, 38 fetuses, 6 neonates, and 6 adults. The results show that, in a histologically immature liver at the end of the embryonic period, CD34 molecules are expressed only on vein endothelium localized in developing portal areas, whereby the difference between portal venous branches and CD34-negative central veins belongs to the collecting venous system. In the fetal period, with aging, expression of CD34 and CD31 molecules on the endothelium of central veins and blood vessels of the portal areas increases. Sinusoidal endothelium shows light and sporadic CD34 immunoreactivity in the late embryonic and fetal periods, and is lost in the neonatal and adult periods, unlike CD31 immunoreactivity, which is poorly expressed in the fetal and neonatal periods but is present in adults. The endothelium of sinusoids and lymphatic vessels express LYVE-1, and the endothelium of lymphatic vessels express LYVE-1 and D2-40 but not CD34. Similarity between the sinusoidal and lymphatic endothelium includes the fact that both types are LYVE-1 positive and CD34 negative.


Asunto(s)
Endotelio Linfático/metabolismo , Endotelio Vascular/metabolismo , Hígado/embriología , Vasos Linfáticos/metabolismo , Adulto , Anciano , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Niño , Desarrollo Embrionario , Células Endoteliales/citología , Células Endoteliales/metabolismo , Endotelio Linfático/citología , Endotelio Vascular/citología , Femenino , Feto/metabolismo , Humanos , Inmunohistoquímica , Recién Nacido , Hígado/citología , Hígado/metabolismo , Vasos Linfáticos/citología , Masculino , Persona de Mediana Edad
15.
J Sports Sci ; 35(3): 302-309, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27019402

RESUMEN

A mathematical model was developed for the assessment of the starting velocity and initial velocity and force of a 100-m sprint, based on a non-homogeneous differential equation with the air resistance proportional to the velocity, and the initial conditions for [Formula: see text], [Formula: see text]The use of this model requires the measurement of reaction time and segmental velocities over the course of the race. The model was validated by comparison with the data obtained from 100-m sprints of men: Carl Lewis (1988), Maurice Green (2001) and Usain Bolt (2009), and women: Florence Griffith-Joyner, Evelyn Ashford and Drechsler Heike (1988) showing a high level of agreement. Combined with the previous work of the authors, the present model allows for the assessment of important physical abilities, such as the exertion of a high starting force, development of high starting velocity and, later on, maximisation of the peak running velocity. These data could be of importance for practitioners to identify possible weaknesses and refine training methods for sprinters and other athletes whose performance depend on rapid movement initiations.


Asunto(s)
Rendimiento Atlético , Conducta Competitiva , Modelos Biológicos , Carrera , Aceleración , Atletas , Fenómenos Biomecánicos , Femenino , Humanos , Masculino , Modelos Teóricos , Movimiento
16.
Drug Dev Res ; 76(1): 17-23, 2015 02.
Artículo en Inglés | MEDLINE | ID: mdl-25619904

RESUMEN

Preclinical Research Potassium (K+ ) channels have a key role in the maintenance of smooth muscle tone; a variety of agonists can modify the tone by altering K+ -channel activity. The aim of this study was assess the effects of the phenols, resveratrol, and naringenin on K+ -channels of the vascular smooth muscle. Segments of human umbilical vein (HUV) without endothelium were precontracted using serotonin (100 µM) or 100 mM K+ to derive cumulative concentration-response curves using increasing concentrations of resveratrol or naringenin. K+ -channel inhibitors were added in the bath before resveratrol (1-100 µM) or naringenin (0.01-1 mM) in assess the role of K+ -channels in their effects on HUV precontracted by serotonin. 4-Aminopiridine (4-AP; 1 mM), a nonselective blocker of voltage-dependent, tetraethylammonium (TEA; 1 mM) and barium chloride (1 mM), a nonselective blocker of Ca2+ -dependent and inward rectifier K+ -channels (respectively) induced significant shifts to the right (P < 0.05) of resveratrol. concentration-response curves. The effect of naringenin was antagonized by 4-AP (1 mM). 4-AP-, TEA-, and barium chloride-sensitive K+ -channels are probably involved in the resveratrol vasodilatatory effect, while naringenin seems to affect 4-AP-sensitive K+ -channels. However, other mechanisms of vasodilation induced by polyphenols could not be excluded. Drug Dev Res, 2015. © 2015 Wiley Periodicals, Inc.

18.
Micromachines (Basel) ; 15(3)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38542642

RESUMEN

The three-point bending test is a valuable method for evaluating the mechanical properties of 3D-printed biomaterials, which can be used in various applications. The use of 3D printing in specimen preparation enables precise control over material composition and microstructure, facilitating the investigation of different printing parameters and advanced materials. The traditional approach to analyzing the mechanical properties of a material using a three-point bending test has the disadvantage that it provides only global information about the material's behavior. This means that it does not provide detailed insight into the local strain distribution within the material. However, the 2D Digital Image Correlation (DIC) method offers additional insight, especially in terms of strain localization. DIC is an optical technique that measures full-field displacements and strains on the surface of a sample. PLA and enhanced PLA-X material were utilized to create three-point bending samples. The aim of this paper was to analyze and compare the influence of aging on the mechanical properties of PLA and enhanced PLA-X materials using three-point bending coupled with the DIC method. The results showed statistically significant differences between the PLA and PLA-X, for both the new and aged materials. The aged PLA samples had the highest average value of maximal force around 68 N, which was an increase of 8.8% compared to the new PLA samples. On the other hand, the aged PLA-X material had an increase of 7.7% in the average maximal force compared to the new PLA-X samples. When comparing the two materials, the PLA samples had higher maximal force values, 6.2% for the new samples, and 7.3% for the aged samples. The DIC results showed that both the new PLA and PLA-X samples endured higher strain values at Points 1 and 2 than the aged ones, except for the aged PLA-X sample at Point 2, where the new sample had higher strain values. However, for the first 5 min of the experiment, both materials exhibited identical behavior, after which point significant differences started to occur for both materials, as well as at Points 1 and 2. A more profound comprehension of the biomechanical characteristics of both PLA and PLA-X material is essential to enhance the knowledge for potential biomedical applications. The DIC method was found to be a powerful tool for analyzing the deformation and failure behavior of samples and for complementing the traditional approach to material testing.

19.
PeerJ Comput Sci ; 10: e1795, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38259888

RESUMEN

Renewable energy plays an increasingly important role in our future. As fossil fuels become more difficult to extract and effectively process, renewables offer a solution to the ever-increasing energy demands of the world. However, the shift toward renewable energy is not without challenges. While fossil fuels offer a more reliable means of energy storage that can be converted into usable energy, renewables are more dependent on external factors used for generation. Efficient storage of renewables is more difficult often relying on batteries that have a limited number of charge cycles. A robust and efficient system for forecasting power generation from renewable sources can help alleviate some of the difficulties associated with the transition toward renewable energy. Therefore, this study proposes an attention-based recurrent neural network approach for forecasting power generated from renewable sources. To help networks make more accurate forecasts, decomposition techniques utilized applied the time series, and a modified metaheuristic is introduced to optimized hyperparameter values of the utilized networks. This approach has been tested on two real-world renewable energy datasets covering both solar and wind farms. The models generated by the introduced metaheuristics were compared with those produced by other state-of-the-art optimizers in terms of standard regression metrics and statistical analysis. Finally, the best-performing model was interpreted using SHapley Additive exPlanations.

20.
Vascul Pharmacol ; 155: 107379, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38762131

RESUMEN

Pulmonary hypertension (PH) is a progressive, severe and to date not curable disease of the pulmonary vasculature. Alterations of the insulin-like growth factor 1 (IGF-1) system are known to play a role in vascular pathologies and IGF-binding proteins (IGFBPs) are important regulators of the bioavailability and function of IGFs. In this study, we show that circulating plasma levels of IGFBP-1, IGFBP-2 and IGFBP-3 are increased in idiopathic pulmonary arterial hypertension (IPAH) patients compared to healthy individuals. These binding proteins inhibit the IGF-1 induced IGF-1 receptor (IGF1R) phosphorylation and exhibit diverging effects on the IGF-1 induced signaling pathways in human pulmonary arterial cells (i.e. healthy as well as IPAH-hPASMCs, and healthy hPAECs). Furthermore, IGFBPs are differentially expressed in an experimental mouse model of PH. In hypoxic mouse lungs, IGFBP-1 mRNA expression is decreased whereas the mRNA for IGFBP-2 is increased. In contrast to IGFBP-1, IGFBP-2 shows vaso-constrictive properties in the murine pulmonary vasculature. Our analyses show that IGFBP-1 and IGFBP-2 exhibit diverging effects on IGF-1 signaling and display a unique IGF1R-independent kinase activation pattern in human pulmonary arterial smooth muscle cells (hPASMCs), which represent a major contributor of PAH pathobiology. Furthermore, we could show that IGFBP-2, in contrast to IGFBP-1, induces epidermal growth factor receptor (EGFR) signaling, Stat-3 activation and expression of Stat-3 target genes. Based on our results, we conclude that the IGFBP family, especially IGFBP-1, IGFBP-2 and IGFBP-3, are deregulated in PAH, that they affect IGF signaling and thereby regulate the cellular phenotype in PH.


Asunto(s)
Modelos Animales de Enfermedad , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina , Factor I del Crecimiento Similar a la Insulina , Miocitos del Músculo Liso , Arteria Pulmonar , Receptor IGF Tipo 1 , Transducción de Señal , Humanos , Animales , Receptor IGF Tipo 1/metabolismo , Receptor IGF Tipo 1/genética , Arteria Pulmonar/metabolismo , Arteria Pulmonar/patología , Arteria Pulmonar/fisiopatología , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 2 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/metabolismo , Miocitos del Músculo Liso/metabolismo , Miocitos del Músculo Liso/patología , Células Cultivadas , Masculino , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Proteína 1 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Fosforilación , Factor de Transcripción STAT3/metabolismo , Estudios de Casos y Controles , Ratones Endogámicos C57BL , Hipertensión Pulmonar Primaria Familiar/metabolismo , Hipertensión Pulmonar Primaria Familiar/fisiopatología , Hipertensión Pulmonar Primaria Familiar/patología , Hipertensión Pulmonar Primaria Familiar/genética , Femenino , Receptores ErbB/metabolismo , Persona de Mediana Edad , Remodelación Vascular , Adulto , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología
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