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Various exogenous factors, such as microbiological and chemical contamination condition food security. Salmonella Typhimurium (S. Typhimurium) is the cause of salmonellosis. This bacterium utilizes phagocytosis to create bacterial reservoirs. On the other hand, exposure to chemical contaminants, such as pesticides, increases susceptibility to numerous infections. Therefore, this research aims to evaluate the effect of co-exposure to diazoxon and S. Typhimurium on the in vitro infection dynamics. For this purpose, human mononuclear cells were pre-exposed in vitro to diazoxon and then challenged with S. Typhimurium at 1, 8, and 24 h. Bacterial internalization, actin polymerization, and reactive oxygen species (ROS) were analyzed. Obtained data show that mononuclear cells previously exposed to diazoxon exhibit greater internalization of S. Typhimurium. Likewise, greater ROS production and an increase in actin polymerization were observed. Therefore, in the proposed scenario, obtained data suggest that co-exposure to diazoxon and S. Typhimurium increases susceptibility to acquiring an illness.
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One hundred years have passed since the death of Élie Metchnikoff (1845-1916). He was the first to observe the uptake of particles by cells and realized the importance of this process, named phagocytosis, for the host response to injury and infection. He also was a strong advocate of the role of phagocytosis in cellular immunity, and with this, he gave us the basis for our modern understanding of inflammation and the innate immune response. Phagocytosis is an elegant but complex process for the ingestion and elimination of pathogens, but it is also important for the elimination of apoptotic cells and hence fundamental for tissue homeostasis. Phagocytosis can be divided into four main steps: (i) recognition of the target particle, (ii) signaling to activate the internalization machinery, (iii) phagosome formation, and (iv) phagolysosome maturation. In this chapter, we present a general view of our current knowledge on phagocytosis performed mainly by professional phagocytes through antibody and complement receptors and discuss aspects that remain incompletely understood.
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Fagocitosis , Fagosomas , Humanos , Animales , Fagosomas/metabolismo , Fagocitos/inmunología , Fagocitos/metabolismo , Transducción de Señal , Inmunidad InnataRESUMEN
[This corrects the article DOI: 10.3389/fvets.2023.1187271.].
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Neutrophils are the most abundant polymorphonuclear granular leukocytes in human blood and are an essential part of the innate immune system. Neutrophils are efficient cells that eliminate pathogenic bacteria and fungi, but their role in dealing with protozoan parasitic infections remains controversial. At sites of protozoan parasite infections, a large number of infiltrating neutrophils is observed, suggesting that neutrophils are important cells for controlling the infection. Yet, in most cases, there is also a strong inflammatory response that can provoke tissue damage. Diseases like malaria, trichomoniasis, leishmaniasis, Chagas disease, and amoebiasis affect millions of people globally. In this review, we summarize these protozoan diseases and describe the novel view on how neutrophils are involved in protection from these parasites. Also, we present recent evidence that neutrophils play a double role in these infections participating both in control of the parasite and in the pathogenesis of the disease.
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The physiological and molecular responses of leukocytes are altered by organophosphate pesticides. Some reports have shown that diazinon causes immunotoxic effects; diazoxon, the oxon metabolite of diazinon, is attributed to influence the immune response by affecting the leukocyte cholinergic system. In this study, the in vitro effects of diazoxon on molecules involved in cell signaling (cAMP, IP3, DAG, JAK1, and STAT3), which play a crucial role in the activation, differentiation, and survival of leukocytes, were evaluated. Data indicate that diazoxon leads to a decrease in cAMP concentration and an increase in basal IP3 levels. However, diazoxon does not affect basal levels of JAK1 and STAT3 phosphorylation. Instead, diazoxon inhibits leukocyte responsiveness to phorbol myristate acetate and ionomycin, substances that, under normal conditions, enhance JAK/STAT signaling. These findings demonstrate that diazoxon significantly affects key molecular parameters related to cell signaling.
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Leucocitos , Sistemas de Mensajero Secundario , Transducción de Señal , Animales , Leucocitos/efectos de los fármacos , Leucocitos/metabolismo , Transducción de Señal/efectos de los fármacos , Sistemas de Mensajero Secundario/efectos de los fármacos , Factor de Transcripción STAT3/metabolismo , AMP Cíclico/metabolismo , Acetato de Tetradecanoilforbol/farmacología , Janus Quinasa 1/metabolismo , Fosforilación/efectos de los fármacos , Ionomicina/farmacología , Insecticidas/toxicidad , Insecticidas/farmacología , Compuestos OrganofosforadosRESUMEN
Neutrophils are fundamental cells in host defense. These leukocytes are quickly recruited from the blood to sites of infection or tissue damage. At these sites, neutrophils initiate several innate immune responses, including phagocytosis, production of reactive oxygen species, degranulation to release proteases and other antimicrobial compounds, production of inflammatory mediators, and formation of neutrophil extracellular traps. In addition to their role in innate immunity, neutrophils are now recognized as cells that also regulate adaptive immunity, via interaction with dendritic cells and lymphocytes. Neutrophils also respond to adaptive immunity by interacting with antibody molecules. Indeed, antibody molecules allow neutrophils to have antigen-specific responses. Neutrophils express different receptors for antibodies. The receptors for immunoglobulin G molecules are known as Fcγ receptors. Upon Fcγ receptor aggregation on the cell membrane, these receptors trigger distinct signal transduction cascades that activate particular cellular responses. In this review, we describe the major Fcγ receptors expressed on human neutrophils and discuss how each Fcγ receptor activates a choice of signaling pathways to stimulate particular neutrophil responses.
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Trampas Extracelulares , Neutrófilos , Humanos , Receptores de IgG/metabolismo , Fagocitosis , Inmunidad Innata , Transducción de Señal , Trampas Extracelulares/metabolismoRESUMEN
Introduction: In veterinary medicine, cancer is the leading cause of death in companion animals, and mammary gland tumors represent the most common neoplasm in female dogs. Several epidemiological risk factors, such as age, breed, hormones, diet, and obesity have been reported to be relevant for canine mammary tumors. Nowadays, the gold standard for diagnosis of canine mammary tumors is the pathological examination of the suspected tissue. However, tumor grade can only be assessed after surgical removal or biopsy of the altered tissue. Therefore, in cases of tumors that could be surgically removed, it would be very helpful to be able to predict the biological behavior of the tumor, before performing any surgery. Since, inflammation constitutes part of the tumor microenvironment and it influences each step of tumorigenesis, cellular and biochemical blood markers of systemic inflammation, such as the neutrophil to lymphocyte ratio (NLR) and the albumin to globulin ratio (AGR) have been proposed as prognostic factors for human cancer development. The NLR and the AGR have not been explored enough as prognostic factors for cancer development in veterinary medicine. Methods: To determine the prognostic value of NLR in canine mammary tumors, clinical records including biochemistry and hematological studies of female dogs with mammary tumors and of control healthy dogs, were used to determine the pre-treatment NLR and AGR. Other clinical data included age, breed, tumor size, histological tumor grade, and survival time after surgery. Results and discussion: It was found that a higher pre-treatment NLR value (NLR > 5) associates with less survival rate. In contrast, the AGR did not show any predictive value on the malignancy of the tumor. However, by combining the NLR with AGR, age of the dog, and tumor size in a principal component analysis (PCA), the grade of the tumor and survival after surgery could be appropriately predicted. These data strongly suggest that pre-treatment NLR values have a prognostic value for the survival rate after surgery of dogs with mammary tumors.
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Organophosphate pesticides (OPs) have greatly facilitated food production worldwide, and their use is not limited to agriculture and the control of pests and disease vectors. However, these substances can directly affect the immune response of non-target organisms. In this sense, exposure to OPs can have negative effects on innate and adaptive immunity, promoting deregulation in humoral and cellular processes such as phagocytosis, cytokine expression, antibody production, cell proliferation, and differentiation, which are crucial mechanisms for host defense against external agents. This review focuses on the scientific evidence of exposure to OPs and their toxic effects on the immune system of non-target organisms (invertebrates and vertebrates) from a descriptive perspective of the immuno-toxic mechanisms associated with susceptibility to the development of bacterial, viral, and fungal infectious diseases. During the exhaustive review, we found that there is an important gap in the study of non-target organisms, examples of which are echinoderms and chondrichthyans. It is therefore important to increase the number of studies on other species directly or indirectly affected by Ops, to assess the degree of impact at the individual level and how this affects higher levels, such as populations and ecosystems.
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Insecticidas , Plaguicidas , Animales , Ecosistema , Invertebrados , Vertebrados , Compuestos Organofosforados , Inmunidad , Organofosfatos , Plaguicidas/toxicidadRESUMEN
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is a global health problem; this has caused thousands of deaths around the world. This infection induces hematologic alterations, and it is necessary to recognize predictive biomarkers to address the need for hospitalization or the severity of the disease. This study aimed to analyze different parameters in outpatients and hospitalized patients infected with SARS-CoV-2 and determine whether hematic biometry can be used for prognosis rapidly. We analyzed 689 patients, of whom 355 were outpatients (162 women and 193 men) and 334 required hospitalization (197 men and 137 women). The average age of the hospitalized patients was 46 years (men, 49 years; women, 52 years), whereas the average age of the outpatients was 49 years (men, 51 years; women, 44 years). Hematologic parameters were analyzed and compared between the outpatients and hospitalized patients. The patients were divided into groups by age and sex. We found that in the hospitalized patients, the erythrocyte, hematocrit, and hemoglobin levels decreased, whereas the outpatients did not experience changes in the erythroid series. In leukocytes, these increased significantly, as they did in neutrophils; however, lymphocytopenia was observed. In the outpatients, we observed normal levels of neutrophils and lymphopenia. We can conclude that hematic biometry can be used as a biomarker, and the relation between neutrophils and lymphocytes is indicated for understanding the development and prognosis of the disease.
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COVID-19 , SARS-CoV-2 , Masculino , Humanos , Femenino , Persona de Mediana Edad , Pacientes Ambulatorios , Pronóstico , HospitalizaciónRESUMEN
To date, the ventricular myocardial band is the anatomical-functional model that best explains cardiac mechanics during systolic-diastolic phenomena in the cardiac cycle. The implications of the model fundamentally affect the anatomical interpretation of the ventricular myocardium, giving meaning to the direction that muscle fibers take, turning them into an object of study with potential clinical, imaging, and surgical applications. Re-interpreting the anatomy of the ventricular muscle justifies changes in the physiological interpretation, from its functional focus as a fiber unraveling the mechanical phenomena carried out during systole and diastole. We identify the functioning of the heart from the electrical and hemodynamic point of view, but it is necessary to delve into the mechanics that originate the hemodynamic changes observed flowmetrically, and that manifested during the pathology. In this review, the mechanical phenomena that the myocardium performs in each phase of the cardiac cycle are broken down in detail, emphasizing the physical displacements that each of the muscle segments presents, as well as a vision of their alteration and in which pathologies they are mainly identified. Visually, an anatomical correlation to the echocardiogram is provided, pointing out the direction of the segmental myocardial displacement by the strain velocity vector technique.
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Corazón , Contracción Miocárdica , Humanos , Contracción Miocárdica/fisiología , Corazón/fisiología , Miocardio/patología , Ventrículos Cardíacos , Diástole/fisiología , Función Ventricular Izquierda/fisiologíaRESUMEN
INTRODUCTION: The COVID-19 pandemic is the result of the SARS-CoV-2 virus, which has caused more than 100 million infections and more than 2.5 million deaths worldwide, representing a serious public health problem. The gold method for detecting this virus is qRT-PCR, which is a semiquantitative technique where the viral load can be established through its cycle threshold (Ct). It has also been reported that COVID-19 generates long-term symptoms (post-COVID-19). METHODS: After three months, a survey was performed on 70 COVID-19 confirmed patients; subsequently, we divided them into four groups (persistent symptoms, chemo-sensitive, cognitive issues, and changes in habit) in order to determine the correlation between viral load and post-COVID-19 symptoms. RESULTS: Data show that fatigue, nervousness, anosmia, and diet changes are common long-term symptoms; in addition, a negative correlation was found between viral load and the number of post-COVID-19 symptoms. CONCLUSION: COVID-19 generates long-term symptoms which can cause problems with psychological and social repercussions.
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COVID-19 , Humanos , Carga Viral , Pacientes Ambulatorios , Pandemias , SARS-CoV-2 , Síndrome , Síndrome Post Agudo de COVID-19RESUMEN
It is common in the numerical simulations for drying of food to suppose that the food does not experience a change of volume. The few numerical studies that include volume changes assume that the shrinkage occurs symmetrically in all directions. Therefore, this effect has not been fully studied, and it is known that not considering it can be detrimental for the accuracy of these simulations. The present study aims to develop a three-dimensional model for the simulation of fruits that includes the volume changes but also takes into consideration the asymmetry of the shrinkage. Physalis peruviana is taken as the subject of study to conduct experiments and imaging analyses that provided data about the drying kinetics and asymmetric shrinkage mode. The effective diffusion coefficient is found to be between 10-12 m2 s-1 and 1.75 × 10-9 m2 s-1. The shrinkage occurs essentially in only one direction, with an average velocity of 8.3 × 10-5 m/min. A numerical modelling scheme is developed that allows including the shrinkage effect in computer simulations. The performance of the model is evaluated by comparison with experimental data, showing that the proposed model decreases more than 4 times the relative error with respect to simulations that do not include volume changes. The proposed model proves to be a useful method that can contribute to more accurate modeling of drying processes.
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Obesity is characterized by an increase in body weight associated with an exaggerated enlargement of the adipose tissue. Obesity has serious negative effects because it is associated with multiple pathological complications such as type 2 diabetes mellitus, cardiovascular diseases, cancer, and COVID-19. Nowadays, 39% of the world population is obese or overweight, making obesity the 21st century epidemic. Obesity is also characterized by a mild, chronic, systemic inflammation. Accumulation of fat in adipose tissue causes stress and malfunction of adipocytes, which then initiate inflammation. Next, adipose tissue is infiltrated by cells of the innate immune system. Recently, it has become evident that neutrophils, the most abundant leukocytes in blood, are the first immune cells infiltrating the adipose tissue. Neutrophils then get activated and release inflammatory factors that recruit macrophages and other immune cells. These immune cells, in turn, perpetuate the inflammation state by producing cytokines and chemokines that can reach other parts of the body, creating a systemic inflammatory condition. In this review, we described the recent findings on the role of neutrophils during obesity and the initiation of inflammation. In addition, we discuss the involvement of neutrophils in the generation of obesity-related complications using diabetes as a prime example.
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COVID-19 , Diabetes Mellitus Tipo 2 , Resistencia a la Insulina , COVID-19/complicaciones , Diabetes Mellitus Tipo 2/patología , Humanos , Inflamación/patología , Neutrófilos/patología , Obesidad/patologíaRESUMEN
Governments have implemented measures to minimize SARS-CoV-2 spread. However, these measures were relaxed, and the appearance of new variants has prompted periods of high contagion known as waves. In Mexico, four waves distributed between July and August 2020, January and February 2021, August and September 2021, and January and February 2022 have appeared. Current health policies discourage mass sampling, preferring to focus on the corrective treatment of severe cases. Outpatients are only advised to undergo brief voluntary confinement and symptomatic treatment, with no follow-up. Therefore, the present study aimed to analyze sex, age, and viral load in outpatients during the four waves in a medium-sized city in Mexico. For each wave, the date of peak contagion was identified, and data were collected within ±15 days. In this regard, data from 916 patients (434 men and 482 women) were analyzed. The age range of positive patients (37-45 years) presented a higher frequency during the first and third waves, while 28-36 years was the most frequent age range during the second and fourth waves, while the viral load values were significantly higher, for both sexes, during the fourth wave. Obtained data of COVID-19 prevalence in population segments can be used for decision-making in the design of effective public health policies.
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COVID-19 , SARS-CoV-2 , Adulto , COVID-19/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pacientes Ambulatorios , Pruebas Serológicas , Carga ViralRESUMEN
Organophosphorus pesticides (OPs) are widespread insecticides used for pest control in agricultural activities and the control of the vectors of human and animal diseases. However, OPs' neurotoxic mechanism involves cholinergic components, which, beyond being involved in the transmission of neuronal signals, also influence the activity of cytokines and other pro-inflammatory molecules; thus, acute and chronic exposure to OPs may be related to the development of chronic degenerative pathologies and other inflammatory diseases. The present article reviews and discusses the experimental evidence linking inflammatory process with OP-induced cholinergic dysregulation, emphasizing the molecular mechanisms related to the role of cytokines and cellular alterations in humans and other animal models, and possible therapeutic targets to inhibit inflammation.
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Plaguicidas , Animales , Colinérgicos , Citocinas , Inflamación , Compuestos Organofosforados/toxicidad , Plaguicidas/toxicidadRESUMEN
Background: The cardiovascular sequelae by the SARS-COV-2 infection is prevalent in a significant portion of the recovered patients from the acute presentation of the SARS-COV-2. Actually, the clinic cardiac control of the post-acute COVID syndrome has been working out without a well-established protocol, making the appropriate diagnosis of the cardiac diseases produced by the different damage mechanisms from COVID-19. Objectives: Standardize cardiovascular care and the follow up of COVID-19 survivors in the function on disease severity and identify patients who develop SPC-19A for timely care. Materials and methods: Through an extensive bibliographic review, this article has the purpose of provide the necessary information to make possible the early diagnosis and following of the cardiac complications that has been recorded trough the months after the acute disease from COVID-19.
Antecedentes: Las secuelas cardiovasculares ocasionadas por la enfermedad por coronavirus 2019 (COVID-19) son frecuentes en una importante proporción de los pacientes recuperados del cuadro agudo de la enfermedad. Hasta el día de hoy el seguimiento cardiológico del síndrome agudo post-COVID-19 (SPC-19A) se ha realizado de forma heterogénea y sin directrices que permitan al clínico identificar oportunamente los cambios que preceden a enfermedades cardiológicas derivadas de los distintos mecanismos de daño inducidos por COVID-19. Objetivos: Estandarizar la atención y seguimiento cardiovascular de los supervivientes de COVID-19 en función de la gravedad de la enfermedad e identificar a los pacientes que desarrollen SPC-19A para su atención oportuna. Material y métodos: Mediante una revisión extensa de bibliografía, este documento tiene la intención de unificar y proporcionar la información necesaria para diagnosticar y dar seguimiento a las complicaciones cardiacas que se han documentado en los meses posteriores a la resolución de la COVID-19 aguda.
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The COVID-19 pandemic highlighted health systems vulnerabilities, as well as thoughtlessness by governments and society. Due to the nature of this contingency, the use of geographic information systems (GIS) is essential to understand the SARS-CoV-2 distribution dynamics within a defined geographic area. This work was performed in Tepic, a medium-sized city in Mexico. The residence of 834 COVID-19 infected individuals was georeferenced and categorized by viral load (Ct). The analysis took place during the maximum contagion of the first four waves of COVID-19 in Mexico, analyzing 158, 254, 143, and 279 cases in each wave respectively. Then heatmaps were built and categorized into five areas ranging from very low to very high risk of contagion, finding that the second wave exhibited a greater number of cases with a high viral load. Additionally, a spatial analysis was performed to measure urban areas with a higher risk of contagion, during this wave this area had 19,203.08 km2 (36.11% of the city). Therefore, a kernel density spatial model integrated by meaningful variables such as the number of infected subjects, viral load, and place of residence in cities, to establish geographic zones with different degrees of infection risk, could be useful for decision-making in future epidemic events.
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COVID-19 , SARS-CoV-2 , COVID-19/epidemiología , Sistemas de Información Geográfica , Humanos , México/epidemiología , Pandemias , Carga ViralRESUMEN
The mitochondrial membrane potential (ΔΨm ) is a parameter often used to determine mitochondrial function; therefore, it can be used to determine the integrity and functionality of cells. A decrement of ΔΨm is implicated in several inflammatory-related pathologies, such phenomena can be related to COVID-19 infection. The present work aimed to compare the ΔΨm in leucocytes (human PBMCs; HPBMC) isolated from healthy control (HC) subjects, patients with COVID-19 (C-19), recovered subjects at 40 ± 13 (R1) and 335 ± 20 (R2) days after infection (dai). Obtained data showed that ΔΨm decreased in HPBMC of subjects with C-19, R1, and R2 compared with HC. When analyzing the ΔΨm data by sex, in females, a significant decrease was observed in R1 and R2 groups versus HC. Regarding men, a significant decrease of ΔΨm was observed in R1, with respect to HC, contrary to R2 group, who reestablished this parameter. Obtained results suggest that the loss of ΔΨm could be related to the long-COVID.
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COVID-19 , COVID-19/complicaciones , Femenino , Humanos , Leucocitos , Masculino , Potencial de la Membrana Mitocondrial , Mitocondrias/metabolismo , Síndrome Post Agudo de COVID-19RESUMEN
Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, anti-viral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for COVID-19 recovery. This work aimed to determine the ex-vivo effects of treatment with fucoidan (20 µg/mL) on mitochondrial membrane potential (ΔΨm, using a cationic cyanine dye, 3,3'-dihexyloxacarbocyanine iodide (DiOC6(3)) on human peripheral blood mononuclear cells (HPBMC) isolated from healthy control (HC) subjects, COVID-19 patients (C-19), and subjects that recently recovered from COVID-19 (R1, 40 ± 13 days after infection). In addition, ex-vivo treatment with fucoidan (20 and 50 µg/mL) was evaluated on ΔΨm loss induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP, 150 µM) in HPBMC isolated from healthy subjects (H) and recovered subjects at 11 months post-COVID-19 (R2, 335 ± 20 days after infection). Data indicate that SARS-CoV-2 infection induces HPBMC loss of ΔΨm, even 11 months after infection, however, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered subjects. Therefore, fucoidan may be a potential treatment to diminish long-term sequelae from COVID-19, using mitochondria as a therapeutic target for the recovery of cellular homeostasis.