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1.
Rev. Fac. Med. UNAM ; 67(4): 7-20, jul.-ago. 2024. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1575776

RESUMEN

Resumen La contaminación ambiental es uno de los factores que favorece el estrés oxidante, ya que expone al organismo a materiales diversos que generan radicales libres y afectan al sistema respiratorio, cardiovascular, inmunológico y nervioso de las personas más vulnerables como los niños, adultos mayores y personas con enfermedades crónicas. Para prevenir o reducir el estrés oxidante, el cual es un desequilibrio entre la producción de radicales libres y la capacidad del organismo de neutralizarlo, se recomienda consumir una dieta equilibrada y rica en antioxidantes naturales los cuales se encuentran diversos alimentos, especialmente en frutas y verduras con colores intensos, en las semillas y las especias. En las últimas décadas se ha demostrado la eficacia del consumo de antioxidantes naturales como: el resveratrol vino, el café, la curcumina, el ajo, la vitamina C, la vitamina E y el té verde que presentan efectos benéficos como: proteger membranas celulares, regular la expresión de genes relacionados con la inflamación, prevenir o reducir el daño endotelial, disminuir la frecuencia o severidad de enfermedades neurodegenerativas, hepáticas y pulmonares, así como estimular al sistema inmunológico.


Abstract Environmental pollution can promote oxidative stress by exposing the body to various elements and substances that generate free radicals, such as lead and vanadium. These free radicals can negatively impact the respiratory, cardiovascular, immune, and neurological systems of vulnerable populations, including children, the elderly, and those with chronic diseases. To prevent or reduce oxidative stress, it is recommended to consume a balanced diet rich in natural antioxidants. These antioxidants can be found in various foods, especially in fruits and vegetables with intense colors, seeds, and spices. In recent decades, the effectiveness of consuming natural antioxidants such as resveratrol found in wine, coffee, curcumin, garlic, vitamin C, vitamin E, and green tea has been demonstrated. These antioxidants have beneficial effects on the body, including the protection of cell membranes, regulation of gene expression associated with inflammation, prevention or reduction of endothelial damage, and the decrease or diminished severity of neurodegeneration, liver, and pulmonary disorders. Additionally, they stimulate the immune response.

2.
Rev. Fac. Med. UNAM ; 67(3): 41-51, may.-jun. 2024. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1569545

RESUMEN

Resumen El sentido del gusto tiene un papel importante porque ha permitido discriminar entre lo que puede ser alimento y lo que no, e incluso en lo que puede ser tóxico o peligroso al ingerirlo. La búsqueda de nuevos sabores está presente en toda la historia de la humanidad. Desde la antigüedad, las especias aportaron nuevas experiencias gustativas para hacer más palatables los alimentos o incluso para conservarlos durante más tiempo. La búsqueda de especias fue una motivación para realizar viajes que llevaron a descubrimiento de nuevas tierras y continentes. Más recientemente, la pandemia por un virus que altera los sentidos del olfato y del gusto, nos ha hecho recordar la importancia de estos sentidos. El sentido del gusto está determinado por unas pequeñas estructuras que se ubican en las papilas linguales. Hay cuatro tipos que definen cinco sabores y uno que aún está en duda. Las alteraciones de este sentido tienen varios posibles orígenes que se comentan en esta revisión.


Abstract Taste is relevant because it has allowed us to discriminate between what is food and what is not, and even what can be toxic or dangerous when ingested. The search for new flavors is present in history of mankind. Since ancient times, the spices provided new taste experiences to make meals more palatable or as a means of preserving food; the search for spices was a motivation to make voyages that led to the discovery of new lands and continents. More recently, a viral pandemic that damages the olfaction and taste senses made us to remember the relevance of the senses. Small structures, called taste buds, located in the papillae of the tongue are responsible of the sense of taste. There are four types of taste buds that identify five tastes and one whose existence has not yet been fully proven. Taste alterations have different etiologies which will be commented on this review.

3.
Rev. Fac. Med. UNAM ; 66(6): 37-52, nov.-dic. 2023. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1535225

RESUMEN

Resumen El endotelio es una monocapa formada por células aplanadas llamadas w, que revisten la parte más interna del corazón, los vasos sanguíneos y los linfáticos. Es considerado un órgano que tiene una función de barrera, pero además se encarga de regular la permeabilidad y tono vascular, hemostasia, inflamación y angiogénesis. Esta revisión se centra sobre todo en las generalidades del endotelio vascular sano y su disfunción. Se analizan los conceptos de activación y disfunción, en donde la activación se considera como un proceso autolimitado, indispensable para la hemostasia y la inflamación. La disfunción endotelial, en cambio, es un proceso patológico, de mayor duración y que se presenta cuando el endotelio ya no puede autorregularse y cambia a un fenotipo proinflamatorio y protrombótico permanente. Esta disfunción es el primer cambio que lleva a la ateroesclerosis y al aumento del riesgo cardiovascular, por esta razón se revisan los principales biomarcadores de disfunción endotelial y riesgo cardiovascular. A medida que se avance en el conocimiento básico del endotelio y su disfunción, será posible diseñar nuevas medidas preventivas o terapéuticas que puedan disminuir dicho riesgo.


Abstract The endothelium is a monolayer of flatten cells named endothelial cells that form the inner layer of the heart, blood, and lymphatic vessels. Its function is not just as a barrier, but it is a regulator of vascular permeability and tone, hemostasis, inflammation, and angiogenesis. This review is about the general aspects of vascular endothelium and endothelial dysfunction that leads to increased vascular risk. Activation and dysfunction are discussed, considering the endothelial activation as a self-limiting process, necessary to promote inflammation and hemostasis. Endothelial dysfunction is a pathological process in which the endothelium loses its ability for self-regulation and acquires a prothrombotic and proinflammation phenotype. Endothelial dysfunction is the initial step for atherosclerosis and increased cardiovascular risk, so the main biomarkers of endothelial dysfunction are reviewed. As basic knowledge about endothelium increases, preventive or therapeutic measures can be designed as treatment or prevention the risk of its dysfunction.

4.
Artículo en Inglés | MEDLINE | ID: mdl-34444206

RESUMEN

Environmental pollution is a worldwide problem recognized by the World Health Organization as a major health risk factor that affects low-, middle- and high-income countries. Suspended particulate matter is among the most dangerous pollutants, since it contains toxicologically relevant agents, such as metals, including vanadium. Vanadium is a transition metal that is emitted into the atmosphere especially by the burning of fossil fuels to which dwellers are exposed. The objective of this literature review is to describe the toxic effects of vanadium and its compounds when they enter the body by inhalation, based especially on the results of a murine experimental model that elucidates the systemic effects that vanadium has on living organisms. To achieve this goal, we reviewed 85 articles on the relevance of vanadium as a component of particulate matter and its toxic effects. Throughout several years of research with the murine experimental model, we have shown that this element generates adverse effects in all the systems evaluated, because it causes immunotoxicity, hematotoxicity, neurotoxicity, nephrotoxicity and reprotoxicity, among other noxious effects. The results with this experimental model add evidence of the effects generated by environmental pollutants and increase the body of evidence that can lead us to make more intelligent environmental decisions for the welfare of all living beings.


Asunto(s)
Contaminantes Atmosféricos , Síndromes de Neurotoxicidad , Administración por Inhalación , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/toxicidad , Animales , Combustibles Fósiles , Ratones , Material Particulado/análisis , Material Particulado/toxicidad , Vanadio/toxicidad
5.
Toxicol Ind Health ; 37(3): 164-172, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33506746

RESUMEN

Air pollution is a worldwide public health issue and it is associated with millions of premature deaths due to cancer, thrombosis, and pulmonary and cardiovascular diseases. Thrombosis is the excessive clotting that blocks a blood vessel, and its etiology is multifactorial. In recent years, growing evidence has linked air pollution, especially particulate matter (PM) and metals, to the development of thrombosis. PM and metals induce lung and systemic inflammation and oxidative stress that are frequent mechanisms in thrombosis. Platelets are important effectors of physiological hemostasis and pathological thrombosis. They are responsible for the formation of the initial plug and are important in the cellular model of coagulation. Therefore, any changes in their morphology or function or an increase in activation could be extremely relevant in thrombosis. Megakaryocytes (MKs) in the bone marrow and in the lungs are the precursor cells of platelets, and the latter is the first organ injured by air pollution. There is substantial evidence of the effect that PM and metals have on platelets, but there is almost no research about the effect of PM and metals on MKs. It is very likely that the alterations produced by air pollution originate in these cells. In this article, we review the biology of MKs and platelets and their role in particulate air pollution-related thrombosis to emphasize the need for further research in this field.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Plaquetas/efectos de los fármacos , Megacariocitos/efectos de los fármacos , Material Particulado/efectos adversos , Trombosis/etiología , Plaquetas/metabolismo , Humanos , Trombosis/inducido químicamente
6.
Rev. Fac. Med. UNAM ; 63(5): 45-57, sep.-oct. 2020. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1155425

RESUMEN

Resumen La pandemia de la enfermedad COVID-19, ocasionada por el virus Sars-CoV-2, ha preocupado al personal de salud, entre otras cosas, por la alta incidencia de coagulopatía asociada a aumento en la mortalidad que se presenta en los pacientes. La coagulopatía es principalmente trombótica, inicialmente en pulmón y posteriormente sistémica, macro y microvascular, asociada al daño endotelial, inflamación, trampas extracelulares de neutrófilos (NETs), activación de macrófagos y tormenta de citocinas que perpetúan el círculo vicioso de trombosis e inflamación. Se ha reportado el aumento de factores protrombóticos en los pacientes: aumento del factor tisular, factor de Von Willebrand, fibrinógeno, factor VIII, entre otros y, además, la disminución de algunos anticoagulantes naturales como la proteína S y la antitrombina. Además, se menciona la insuficiencia de la fibrinólisis, asociada con el aumento del PAI-1 (inhibidor del activador tisular de plasminógeno). Durante la enfermedad, hay depósito de fibrina intraalveolar que también es degradada. Tanto la fibrinólisis del trombo, como la degradación de fibrina intraalveolar, hacen que aumenten los dímeros D y, por esta razón, este es uno de los mejores predictores de la severidad de la enfermedad COVID-19. En este artículo se revisa la fisiología de la hemostasia, la tromboinflamación secundaria a la infección por el virus Sars-Cov-2, la evidencia clínica y lo que se sabe de la fisiopatología de la coagulopatía en COVID-19, para tratar de entenderla desde la mirada de la ciencia básica.


Abstract COVID-19 global pandemic caused by Sars-CoV-2 virus, has worried to health care providers due to the high mortality rate related to coagulopathy in many patients. COVID-19 coagulopathy is mainly thrombotic, first locally in lungs but later on it becomes micro and macrovascular systemic coagulopathy. It has been associated to endothelial damage, inflammation, neutrophil-extracellular traps, monocyte and macrophage activation, cytokines storm that induce a vicious cycle of thrombosis and inflammation. The increased levels of prothrombotic factors as tissue factor, Von Willebrand factor, fibrinogen, VIII factor and the decreased levels of antithrombotic factos, such as: antithrombin and Protein S have been reported in COVID-19 patients. Insufficiency of fibrinolysis because of the increased levels of PAI-1 (plasminogen activator inhibitor 1) have been reported also. During this disease there are intraalveolar fibrin deposits that needs to be degraded. Fibrinolysis of thrombus and fibrin intraalveolar degradation are responsible for the high increase of D-dimers levels that are an important predictor of severity of the disease. In this report, the physiology of hemostasis, thromboinflamation secondary to Sars-CoV-2 infection are reviewed, as well as the clinical evidence and the physiopathology of COVID-19 coagulopathy from the basic sciences point of view.

7.
Histol Histopathol ; 35(5): 497-508, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31531844

RESUMEN

The Non-Ciliated Bronchiolar Cell (NCBC) is responsible for the defense and maintenance of the bronchiolar epithelium. Several cellular defense mechanisms have been associated with an increase in the secretion of CC16 and changes in the phenotype of the cell; these mechanisms could be linked to tolerance to the damage due to exposure to inhaled Particulate Matter (PM) of the epithelium. These defense mechanisms have not been sufficiently explored. In this article, we studied the response of the NCBC to inhaled vanadium, an element which adheres to PM. This response was measured by the changes in the phenotype of the NCBC and the secretion of CC16 in a mouse model. Mice were exposed in two phases to different vanadium concentrations; 1.27 mg/m³ in the first phase and 2.56 mg/m³ in the second phase. Mice were sacrificed on the 2nd, 4th, 5th, 6th and 8th weeks. In the second phase, we observed the following: sloughing of the NCBC, hyperplasia and small inflammatory foci remained without changes and that the expression of CC16 was higher in this phase than in phase I. We also observed a change in the phenotype with a slow decrease in both phases. The increase in the secretion of CC16 and the phenotype reversion could be due to the anti-inflammatory activity of CC16. The changes observed in the second phase could be attributed to the tolerance to inhaled vanadium.


Asunto(s)
Bronquiolos , Células Epiteliales , Uteroglobina/metabolismo , Vanadio/toxicidad , Contaminantes Atmosféricos/toxicidad , Animales , Antiinflamatorios/metabolismo , Bronquiolos/citología , Bronquiolos/metabolismo , Bronquiolos/patología , Tolerancia a Medicamentos/fisiología , Células Epiteliales/metabolismo , Células Epiteliales/patología , Epitelio/metabolismo , Epitelio/patología , Inflamación , Inhalación , Pulmón/metabolismo , Ratones , Material Particulado/toxicidad
8.
Rev. Fac. Med. UNAM ; 62(1): 6-18, ene.-feb. 2019. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1013219

RESUMEN

Resumen El megacariocito es la célula más grande de la médula ósea, por lo tanto es relativamente fácil reconocer su presencia al observar un aspirado o una biopsia de este tejido. Difiere de otras células por su tamaño, por ser poliploide y crecer por endomitosis. No hay otra célula humana que crezca así. Además, tiene funciones biológicas muy importantes. La más conocida es el dar origen a las plaquetas, que son indispensables para la hemostasia y la reparación de los vasos sanguíneos dañados, así como para la cicatrización de los tejidos que rodean a las heridas. Sin embargo, en los últimos años, a los megacariocitos también se les han atribuido algunas otras funciones que discutiremos en esta revisión.


Abstract The Megakaryocyte is the biggest cell in the bone marrow; therefore, it is easy to recognize in a bone marrow aspirate. In humans, this cell differs from others because of its size, its polyploidy and because it grows by endomitosis. It is the only human cell that grows this way. In addition, the megakaryocyte has very important biological functions. Its best-known function is being in charge of the production of platelets, which are essential for hemostasis, the repair of damaged blood vessels, and healing the tissues surrounding wounds. However, in recent years, other functions have been attributed to the megakaryocyte, which will be discussed in this review.

9.
J Immunotoxicol ; 14(1): 9-14, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28090785

RESUMEN

The thymus is a vital immune system organ wherein selection of T-lymphocytes occurs in a process regulated by dendritic and epithelial thymic cells. Previously, we have reported that in a mouse model of vanadium inhalation, a decrease in CD11c dendritic cells was observed. In the present study, we report on a thymic cortex-medulla distribution distortion in these hosts due to apparent effects of the inhaled vanadium on cytokeratin-5 (K5+) epithelial cells in the same mouse model - after 1, 2, and 4 weeks of exposure - by immunohistochemistry. These cells - together with dendritic cells - eliminate autoreactive T-cell clones and regulate the production of regulatory T-cells in situ. Because both cell types are involved in the negative selection of autoreactive clones, a potential for an increase in development of autoimmune conditions could be a possible consequence among individuals who might be exposed often to vanadium in air pollution, including dwellers of highly polluted cities with elevated levels of particulate matter onto which vanadium is often adsorbed.


Asunto(s)
Células Dendríticas/inmunología , Células Epiteliales/inmunología , Material Particulado/inmunología , Linfocitos T/inmunología , Timo/patología , Vanadio/inmunología , Animales , Autoinmunidad , Antígeno CD11c/metabolismo , Comunicación Celular , Supresión Clonal , Células Clonales , Humanos , Inmunohistoquímica , Inhalación , Queratina-5/metabolismo , Ratones , Ratones Endogámicos , Material Particulado/toxicidad , Vanadio/toxicidad
10.
Histol Histopathol ; 31(4): 433-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26568576

RESUMEN

Particulate matter air pollution has considerably increased during the last decades; vanadium is a transition element adhered to this particulate matter, and the combustion of fossil fuels is the main source in the atmosphere. It has been reported that air pollution and specifically vanadium exposure increases the probability of suffering arrhythmias; however the biological mechanism of such a relationship remains unknown. It has been established that a diminished presence of N-Cadherin alters the Connexin-43 arrangement, and the consequent altered presence of these proteins predisposes to ventricular heart rate problems. We analyzed myocardial histology and the expression of N-Cadherin and Connexin-43 by immunohistochemistry in mouse that inhaled vanadium. Our results showed a significant and progressive reduction in both N-Cadherin and Connexin-43, as well as the presence of meganucleus; myofibrils disruption, and clumping in the exposed groups were also observed. Our findings add more information about a possible explanation for the arrythmogenic effect observed in dwellers of cities with high particulate matter atmospheric pollution.


Asunto(s)
Cadherinas/metabolismo , Conexina 43/metabolismo , Corazón/efectos de los fármacos , Miocardio/metabolismo , Material Particulado/toxicidad , Vanadio/toxicidad , Contaminación del Aire , Animales , Inmunohistoquímica , Masculino , Ratones
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