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1.
Int J Mol Sci ; 25(15)2024 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-39125801

RESUMEN

Mannheimia haemolytica is the main etiological bacterial agent in ruminant respiratory disease. M. haemolytica secretes leukotoxin, lipopolysaccharides, and proteases, which may be targeted to treat infections. We recently reported the purification and in vivo detection of a 110 kDa Zn metalloprotease with collagenase activity (110-Mh metalloprotease) in a sheep with mannheimiosis, and this protease may be an important virulence factor. Due to the increase in the number of multidrug-resistant strains of M. haemolytica, new alternatives to antibiotics are being explored; one option is lactoferrin (Lf), which is a multifunctional iron-binding glycoprotein from the innate immune system of mammals. Bovine apo-lactoferrin (apo-bLf) possesses many properties, and its bactericidal and bacteriostatic effects have been highlighted. The present study was conducted to investigate whether apo-bLf inhibits the secretion and proteolytic activity of the 110-Mh metalloprotease. This enzyme was purified and sublethal doses of apo-bLf were added to cultures of M. haemolytica or co-incubated with the 110-Mh metalloprotease. The collagenase activity was evaluated using zymography and azocoll assays. Our results showed that apo-bLf inhibited the secretion and activity of the 110-Mh metalloprotease. Molecular docking and overlay assays showed that apo-bLf bound near the active site of the 110-Mh metalloprotease, which affected its enzymatic activity.


Asunto(s)
Lactoferrina , Mannheimia haemolytica , Metaloproteasas , Proteolisis , Lactoferrina/metabolismo , Lactoferrina/farmacología , Metaloproteasas/metabolismo , Metaloproteasas/antagonistas & inhibidores , Animales , Apoproteínas/metabolismo , Apoproteínas/química , Simulación del Acoplamiento Molecular , Ovinos , Bovinos , Colagenasas/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/química , Zinc/metabolismo
2.
Antioxidants (Basel) ; 13(3)2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38539791

RESUMEN

Aging is characterized by increased reactive species, leading to redox imbalance, oxidative damage, and senescence. The adverse effects of alcohol consumption potentiate aging-associated alterations, promoting several diseases, including liver diseases. Nucleoredoxin (NXN) is a redox-sensitive enzyme that targets reactive oxygen species and regulates key cellular processes through redox protein-protein interactions. Here, we determine the effect of chronic alcohol consumption on NXN-dependent redox interactions in the liver of aged mice. We found that chronic alcohol consumption preferentially promotes the localization of NXN either into or alongside senescent cells, declines its interacting capability, and worsens the altered interaction ratio of NXN with FLII, MYD88, CAMK2A, and PFK1 proteins induced by aging. In addition, carbonylated protein and cell proliferation increased, and the ratios of collagen I and collagen III were inverted. Thus, we demonstrate an emerging phenomenon associated with altered redox homeostasis during aging, as shown by the declining capability of NXN to interact with partner proteins, which is enhanced by chronic alcohol consumption in the mouse liver. This evidence opens an attractive window to elucidate the consequences of both aging and chronic alcohol consumption on the downstream signaling pathways regulated by NXN-dependent redox-sensitive interactions.

3.
Pathogens ; 13(1)2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38251351

RESUMEN

Naegleria fowleri is a ubiquitous free-living amoeba that causes primary amoebic meningoencephalitis. As a part of the innate immune response at the mucosal level, the proteins lactoferrin (Lf) and lysozyme (Lz) are secreted and eliminate various microorganisms. We demonstrate that N. fowleri survives the individual and combined effects of bovine milk Lf (bLf) and chicken egg Lz (cLz). Moreover, amoebic proliferation was not altered, even at 24 h of co-incubation with each protein. Trophozoites' ultrastructure was evaluated using transmission electron microscopy, and these proteins did not significantly alter their organelles and cytoplasmic membranes. Protease analysis using gelatin-zymograms showed that secreted proteases of N. fowleri were differentially modulated by bLf and cLz at 3, 6, 12, and 24 h. The bLf and cLz combination resulted in the inhibition of N. fowleri-secreted proteases. Additionally, the use of protease inhibitors on bLf-zymograms demonstrated that secreted cysteine proteases participate in the degradation of bLf. Nevertheless, the co-incubation of trophozoites with bLf and/or cLz reduced the cytopathic effect on the MDCK cell line. Our study suggests that bLf and cLz, alone or together, inhibited secreted proteases and reduced the cytopathic effect produced by N. fowleri; however, they do not affect the viability and proliferation of the trophozoites.

4.
Int J Mol Sci ; 24(13)2023 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-37446394

RESUMEN

Entamoeba histolytica (E. histolytica) is a parasite in humans that provokes amoebiasis. The most employed drug is metronidazole (MTZ); however, some studies have reported that this drug induces genotoxic effects. Therefore, it is necessary to explore new compounds without toxicity that can eliminate E. histolytica. Flavonoids are polyphenolic compounds that have demonstrated inhibition of growth and dysregulation of amoebic proteins. Despite the knowledge acquired to date, action mechanisms are not completely understood. The present work evaluates the effect of kaempferol against E. histolytica trophozoites and in the interactions with neutrophils from hamster, which is a susceptibility model. Our study demonstrated a significant reduction in the amoebic viability of trophozoites incubated with kaempferol at 150 µM for 90 min. The gene expression analysis showed a significant downregulation of Pr (peroxiredoxin), Rr (rubrerythrin), and TrxR (thioredoxin reductase). In interactions with amoebae and neutrophils for short times, we observed a reduction in ROS (reactive oxygen species), NO (nitric oxide), and MPO (myeloperoxidase) neutrophil activities. In conclusion, we confirmed that kaempferol is an effective drug against E. histolytica through the decrease in E. histolytica antioxidant enzyme expression and a regulator of several neutrophil mechanisms, such as MPO activity and the regulation of ROS and NO.


Asunto(s)
Amoeba , Entamoeba histolytica , Humanos , Animales , Cricetinae , Neutrófilos/metabolismo , Trofozoítos , Especies Reactivas de Oxígeno/metabolismo , Quempferoles/farmacología , Quempferoles/metabolismo
5.
Front Cell Infect Microbiol ; 13: 1150054, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37360530

RESUMEN

The protozoan disease is a major global health concern. Amoebiasis, leishmaniasis, Chagas disease, and African sleeping sickness affect several million people worldwide, leading to millions of deaths annually and immense social and economic problems. Iron is an essential nutrient for nearly all microbes, including invading pathogens. The majority of iron in mammalian hosts is stored intracellularly in proteins, such as ferritin and hemoglobin (Hb). Hb, present in blood erythrocytes, is a very important source of iron and amino acids for pathogenic microorganisms ranging from bacteria to eukaryotic pathogens, such as worms, protozoa, yeast, and fungi. These organisms have developed adequate mechanisms to obtain Hb or its byproducts (heme and globin) from the host. One of the major virulence factors identified in parasites is parasite-derived proteases, essential for host tissue degradation, immune evasion, and nutrient acquisition. The production of Hb-degrading proteases is a Hb uptake mechanism that degrades globin in amino acids and facilitates heme release. This review aims to provide an overview of the Hb and heme-uptake mechanisms utilized by human pathogenic protozoa to survive inside the host.


Asunto(s)
Parásitos , Animales , Humanos , Parásitos/metabolismo , Hemoglobinas/metabolismo , Hemo/metabolismo , Endopeptidasas , Péptido Hidrolasas , Hierro/metabolismo , Mamíferos/metabolismo
6.
Microorganisms ; 11(3)2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36985284

RESUMEN

Acanthamoeba castellanii genotype T4 is a clinically significant free-living amoeba that causes granulomatous amoebic encephalitis and amoebic keratitis in human beings. During the initial stages of infection, trophozoites interact with various host immune responses, such as lactoferrin (Lf), in the corneal epithelium, nasal mucosa, and blood. Lf plays an important role in the elimination of pathogenic microorganisms, and evasion of the innate immune response is crucial in the colonization process. In this study, we describe the resistance of A. castellanii to the microbicidal effect of bovine apo-lactoferrin (apo-bLf) at different concentrations (25, 50, 100, and 500 µM). Acanthamoeba castellanii trophozoites incubated with apo-bLf at 500 µM for 12 h maintained 98% viability. Interestingly, despite this lack of effect on viability, our results showed that the apo-bLf inhibited the cytopathic effect of A. castellanii in MDCK cells culture, and analysis of amoebic proteases by zymography showed significant inhibition of cysteine and serine proteases by interaction with the apo-bLf. From these results, we conclude that bovine apo-Lf influences the activity of A. castellanii secretion proteases, which in turn decreases amoebic cytopathic activity.

7.
Radiol Case Rep ; 18(1): 349-352, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36411847

RESUMEN

Totally implanted central venous port systems are widely used to access central veins for patients needing long-term therapy. These devices have low rates of complications and are commonly used to administer medications like chemotherapeutic agents. Spontaneous rupture of a catheter segment is a rare mechanical complication, usually belatedly diagnosed and presenting with complications. We present a case of a spontaneously ruptured chemotherapy catheter diagnosed using a novel approach via oblique projections on chest X-rays and successfully removed using an endovascular approach.

8.
Curr Pharm Des ; 28(40): 3243-3260, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36284379

RESUMEN

The emergence of multidrug-resistant bacterial strains with respect to commercially available antimicrobial drugs has marked a watershed in treatment therapies to fight pathogens and has stimulated research on alternative remedies. Proteins of the innate immune system of mammals have been highlighted as potentially yielding possible treatment options for infections. Lactoferrin (Lf) is one of these proteins; interestingly, no resistance to it has been found. Lf is a conserved cationic nonheme glycoprotein that is abundant in milk and is also present in low quantities in mucosal secretions. Moreover, Lf is produced and secreted by the secondary granules of neutrophils at infection sites. Lf is a molecule of approximately 80 kDa that displays multiple functions, such as antimicrobial, anti-viral, anti-inflammatory, and anticancer actions. Lf can synergize with antibiotics, increasing its potency against bacteria. Lactoferricins (Lfcins) are peptides resulting from the N-terminal end of Lf by proteolytic cleavage with pepsin. They exhibit several anti-bacterial effects similar to those of the parental glycoprotein. Synthetic analog peptides exhibiting potent antimicrobial properties have been designed. The aim of this review is to update understanding of the structure and effects of Lf and Lfcins as anti-bacterial compounds, focusing on the mechanisms of action in bacteria and the use of Lf in treatment of infections in patients, including those studies where no significant differences were found. Lf could be an excellent option for prevention and treatment of bacterial diseases, mainly in combined therapies with antibiotics or other antimicrobials.


Asunto(s)
Antiinfecciosos , Infecciones Bacterianas , Animales , Humanos , Lactoferrina/farmacología , Lactoferrina/uso terapéutico , Antiinfecciosos/farmacología , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Infecciones Bacterianas/tratamiento farmacológico , Bacterias , Péptidos/metabolismo , Mamíferos/metabolismo
9.
Pharmaceutics ; 14(8)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-36015327

RESUMEN

Parasites and other eventually pathogenic organisms require the ability to adapt to different environmental conditions inside the host to assure survival. Some host proteins have evolved as defense constituents, such as lactoferrin (Lf), which is part of the innate immune system. Lf in its iron-free form (apo-Lf) and its peptides obtained by cleavage with pepsin are microbicides. Parasites confront Lf in mucosae and blood. In this work, the activity of Lf against pathogenic and opportunistic parasites such as Cryptosporidium spp., Eimeria spp., Entamoeba histolytica, Giardia duodenalis, Leishmania spp., Trypanosoma spp., Plasmodium spp., Babesia spp., Toxoplasma gondii, Trichomonas spp., and the free-living but opportunistic pathogens Naegleria fowleri and Acanthamoeba castellani were reviewed. The major effects of Lf could be the inhibition produced by sequestering the iron needed for their survival and the production of oxygen-free radicals to more complicated mechanisms, such as the activation of macrophages to phagocytes with the posterior death of those parasites. Due to the great interest in Lf in the fight against pathogens, it is necessary to understand the exact mechanisms used by this protein to affect their virulence factors and to kill them.

10.
Molecules ; 25(24)2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33302377

RESUMEN

Due to the emergence of multidrug-resistant pathogens, it is necessary to develop options to fight infections caused by these agents. Lactoferrin (Lf) is a cationic nonheme multifunctional glycoprotein of the innate immune system of mammals that provides numerous benefits. Lf is bacteriostatic and/or bactericidal, can stimulate cell proliferation and differentiation, facilitate iron absorption, improve neural development and cognition, promote bone growth, prevent cancer and exert anti-inflammatory and immunoregulatory effects. Lactoferrin is present in colostrum and milk and is also produced by the secondary granules of polymorphonuclear leukocytes, which store this glycoprotein and release it at sites of infection. Lf is also present in many fluids and exocrine secretions, on the surfaces of the digestive, respiratory and reproductive systems that are commonly exposed to pathogens. Apo-Lf (an iron-free molecule) can be microbiostatic due to its ability to capture ferric iron, blocking the availability of host iron to pathogens. However, apo-Lf is mostly microbicidal via its interaction with the microbial surface, causing membrane damage and altering its permeability function. Lf can inhibit viral entry by binding to cell receptors or viral particles. Lf is also able to counter different important mechanisms evolved by microbial pathogens to infect and invade the host, such as adherence, colonization, invasion, production of biofilms and production of virulence factors such as proteases and toxins. Lf can also cause mitochondrial and caspase-dependent regulated cell death and apoptosis-like in pathogenic yeasts. All of these mechanisms are important targets for treatment with Lf. Holo-Lf (the iron-saturated molecule) can contain up to two ferric ions and can also be microbicidal against some pathogens. On the other hand, lactoferricins (Lfcins) are peptides derived from the N-terminus of Lf that are produced by proteolysis with pepsin under acidic conditions, and they cause similar effects on pathogens to those caused by the parental Lf. Synthetic analog peptides comprising the N-terminus Lf region similarly exhibit potent antimicrobial properties. Importantly, there are no reported pathogens that are resistant to Lf and Lfcins; in addition, Lf and Lfcins have shown a synergistic effect with antimicrobial and antiviral drugs. Due to the Lf properties being microbiostatic, microbicidal, anti-inflammatory and an immune modulator, it represents an excellent natural alternative either alone or as adjuvant in the combat to antibiotic multidrug-resistant bacteria and other pathogens. This review aimed to evaluate the data that appeared in the literature about the effects of Lf and its derived peptides on pathogenic bacteria, protozoa, fungi and viruses and how Lf and Lfcins inhibit the mechanisms developed by these pathogens to cause disease.


Asunto(s)
Antiinfecciosos/química , Antiinfecciosos/farmacología , Lactoferrina/química , Lactoferrina/farmacología , Péptidos/química , Péptidos/farmacología , Animales , Antiinfecciosos/síntesis química , Antiparasitarios/síntesis química , Antiparasitarios/química , Antiparasitarios/farmacología , Bacterias/efectos de los fármacos , Adhesión Bacteriana/efectos de los fármacos , Pared Celular/efectos de los fármacos , Técnicas de Química Sintética , Hongos/efectos de los fármacos , Interacciones Huésped-Patógeno , Humanos , Péptidos/síntesis química , Proteolisis/efectos de los fármacos , Relación Estructura-Actividad , Virulencia/efectos de los fármacos , Factores de Virulencia , Virus/efectos de los fármacos
11.
Scientifica (Cairo) ; 2020: 7064745, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32908783

RESUMEN

To know the dynamics of net assimilation rate and the agronomic efficiency of nitrogen in the Tartago crop, seeds of three accessions were collected in Teotitlán de Flores Magón, Oaxaca, Mexico. The treatments consisted of nitrogen fertilization of 0, 20, 40, 60, 80, 100, 120, and 140 kg (N) ha-1, evaluated under a completely randomized design. The experimental unit was constituted by a Tartago plant inside of a polyethylene bag with soil of the zone, and four repetitions were considered. The response variables were dry biomass, number of fruits per plant, agronomic yield, harvest index, nitrogen agronomic efficiency, SPAD units, and net assimilation rate. The results indicate that climatic conditions did not influence the growth and development of the crop. The maximum values for all of response variables were achieved with the application of nitrogen in a range of 60 to 140 kg ha-1. The net assimilation rate was adjusted to a quadratic model. It is concluded that the Tartago responds positively to the application of nitrogen and can be an alternative to be grown in dry climate.

12.
Future Microbiol ; 15: 919-936, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32716210

RESUMEN

Currently, there is growing interest in the identification and purification of microbial lectins due to their involvement in the pathogenicity mechanisms of pathogens, such as Entamoeba histolytica and free-living amoebae. The Gal/GalNAc lectin from E. histolytica participates in adhesion, cytotoxicity and regulation of immune responses. Furthermore, mannose- and galactose-binding protein have been described in Acanthamoeba castellanii and Balamuthia mandrillaris, respectively and they also contribute to host damage. Finally, in Naegleria fowleri, molecules containing mannose and fucose are implicated in adhesion and cytotoxicity. Considering their relevance in the pathogenesis of the diseases caused by these protozoa, lectins appear to be promising targets in the diagnosis, vaccination and treatment of these infections.


Asunto(s)
Amoeba/efectos de los fármacos , Entamoeba histolytica/efectos de los fármacos , Lectinas/farmacología , Factores de Virulencia , Amebiasis/diagnóstico , Animales , Balamuthia mandrillaris , Entamebiasis/diagnóstico , Entamebiasis/tratamiento farmacológico , Entamebiasis/parasitología , Glicoconjugados , Glicoproteínas , Interacciones Huésped-Parásitos , Humanos , Naegleria fowleri , Vacunación
13.
Eur J Cell Biol ; 99(5): 151085, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32646643

RESUMEN

The Naegleria are ubiquitous free-living amoebae and are characterized by the presence of three phases in their biological cycle: trophozoite, cyst and flagellate. Of this genus, only Naegleria fowleri has been reported as pathogenic to humans. The proteasome is a multi-catalytic complex and is considered to be the most important structure responsible for the degradation of intracellular proteins. This structure is related to the maintenance of cellular homeostasis and, in pathogenic microorganisms, to the modulation of their virulence. Until now, the proteasome and its function have not been described for the Naegleria genus. In the current study, using bioinformatic analysis, protein sequences homologous to those reported for the subunits of the 20S proteasome in other organisms were found, and virtual modelling was used to determine their three-dimensional structure. The presence of structural and catalytic subunits of the 20S proteasome was detected by Western and dot blot assays. Its localization was observed by immunofluorescence microscopy to be mainly in the cytoplasm, and a leading role of the chymotrypsin-like catalytic activity was determined using fluorogenic peptidase assays and specific proteasome inhibitors. Finally, the role of the 20S proteasome in the proliferation and differentiation of Naegleria genus trophozoites was demonstrated.


Asunto(s)
Naegleria fowleri/química , Complejo de la Endopetidasa Proteasomal/metabolismo , Secuencia de Aminoácidos , Animales , Diferenciación Celular , Proliferación Celular
14.
J Leukoc Biol ; 108(3): 895-908, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32531828

RESUMEN

Naegleria fowleri produces a fatal disease called primary amebic meningoencephalitis (PAM), which is characterized by an extensive inflammatory reaction in the CNS. It is known that the immune response is orchestrated mainly by neutrophils, which activate several defense mechanisms in the host, including phagocytosis, the release of different enzymes such as myeloperoxidase (MPO), and the production of neutrophil extracellular traps. However, the mechanisms by which amoebas evade the neutrophil response are still unknown. In this study, we analyzed the ability of N. fowleri to respond to the stress exerted by MPO. Interestingly, after the interaction of trophozoites with neutrophils, the amoeba viability was not altered; however, ultrastructural changes were observed. To analyze the influence of MPO against N. fowleri and its participation in free radical production, we evaluated its enzymatic activity, expression, and localization with and without the specific 4-aminobenzoic acid hydrazide inhibitor. The production of oxidizing molecules is the principal mechanism used by neutrophils to eliminate pathogens. In this context, we demonstrated an increase in the production of NO, superoxide anion, and reactive oxygen species; in addition, the overexpression of several antioxidant enzymes present in the trophozoites was quantified. The findings strongly suggest that N. fowleri possesses antioxidant machinery that is activated in response to an oxidative environment, allowing it to evade the neutrophil-mediated immune response, which may contribute to the establishment of PAM.


Asunto(s)
Interacciones Huésped-Parásitos/inmunología , Naegleria fowleri/metabolismo , Neutrófilos/fisiología , Oxidorreductasas/biosíntesis , Peroxidasa/fisiología , Proteínas Protozoarias/biosíntesis , Compuestos de Anilina/farmacología , Animales , Forma de la Célula , Gránulos Citoplasmáticos/enzimología , Gránulos Citoplasmáticos/ultraestructura , Inducción Enzimática , Lipopolisacáridos/farmacología , Masculino , Ratones , Ratones Endogámicos BALB C , Naegleria fowleri/enzimología , Naegleria fowleri/crecimiento & desarrollo , Naegleria fowleri/ultraestructura , Neutrófilos/efectos de los fármacos , Óxido Nítrico/metabolismo , Oxidación-Reducción , Estrés Oxidativo , Oxidorreductasas/genética , Peroxidasa/antagonistas & inhibidores , Proteínas Protozoarias/genética , Especies Reactivas de Oxígeno , Superóxidos/metabolismo , Vacuolas/ultraestructura
15.
Int J Med Microbiol ; 310(1): 151358, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31587966

RESUMEN

Amoebiasis is a parasitic disease caused by Entamoeba histolytica (E. histolytica), an extracellular enteric protozoan. This infection mainly affects people from developing countries with limited hygiene conditions, where it is endemic. Infective cysts are transmitted by the fecal-oral route, excysting in the terminal ileum and producing invasive trophozoites (amoebae). E. histolytica mainly lives in the large intestine without causing symptoms; however, possibly as a result of so far unknown signals, the amoebae invade the mucosa and epithelium causing intestinal amoebiasis. E. histolytica possesses different mechanisms of pathogenicity for the adherence to the intestinal epithelium and for degrading extracellular matrix proteins, producing tissue lesions that progress to abscesses and a host acute inflammatory response. Much information has been obtained regarding the virulence factors, metabolism, mechanisms of pathogenicity, and the host immune response against this parasite; in addition, alternative treatments to metronidazole are continually emerging. An accesible and low-cost diagnostic method that can distinguish E. histolytica from the most nonpathogenic amoebae and an effective vaccine are necessary for protecting against amoebiasis. However, research about the disease and its prevention has been a challenge due to the relationship between E. histolytica and the host during the distinct stages of the disease is multifaceted. In this review, we analyze the interaction between the parasite, the human host, and the colon microbiota or pathogenic microorganisms, which together give rise to intestinal amoebiasis.


Asunto(s)
Amebiasis/parasitología , Países en Desarrollo , Disentería Amebiana/parasitología , Intestinos/parasitología , Salud Pública , Amebiasis/tratamiento farmacológico , Amebiasis/epidemiología , Animales , Antiprotozoarios/uso terapéutico , Disentería Amebiana/epidemiología , Entamoeba histolytica/inmunología , Entamoeba histolytica/patogenicidad , Heces/parasitología , Microbioma Gastrointestinal , Interacciones Huésped-Patógeno , Humanos , Intestinos/microbiología , Metronidazol/uso terapéutico , Ratones , Virulencia
16.
Parasitol Int ; 74: 102002, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31669294

RESUMEN

Acanthamoeba spp. are free-living amoebae with a worldwide distribution. These amoebae can cause granulomatous amoebic encephalitis and amoebic keratitis in humans. Proteases are considered virulence factors in pathogenic Acanthamoeba. The objective of this study was to evaluate the behavior of Acanthamoeba mauritaniensis, a nonpathogenic amoeba. We analyzed the cytopathic effect of A. mauritaniensis on RCE1(5 T5) and MDCK cells and compared it to that of Acanthamoeba castellanii. A partial biochemical characterization of proteases was performed in total crude extracts (TCE) and conditioned medium (CM). Finally, we evaluated the effect of proteases on tight junction (TJ) proteins and the transepithelial electrical resistance of MDCK cells. The results showed that this amoeba can induce substantial damage to RCE1(5T5) and MDCK cells. Moreover, the zymograms and Azocoll assays of amoebic TCE and CM revealed different protease activities, with serine proteases being the most active. Furthermore, A. mauritaniensis induced the alteration and degradation of MDCK cell TJ proteins with serine proteases. After genotyping this amoeba, we determined that it is an isolate of Acanthamoeba genotype T4D. From these data, we suggest that A. mauritaniensis genotype T4D behaves similarly to the A. castellanii strain.


Asunto(s)
Acanthamoeba/genética , Acanthamoeba/patogenicidad , Genotipo , Acanthamoeba/enzimología , Animales , Perros , Células Epiteliales/parasitología , Células Epiteliales/patología , Células de Riñón Canino Madin Darby , Serina Proteasas/metabolismo , Proteínas de Uniones Estrechas/metabolismo
17.
Eur J Protistol ; 72: 125640, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31794894

RESUMEN

The plasma membrane is essential in the pathogenicity of several microorganisms. However, to date, there are few studies related to the plasma membrane proteins in Naegleria fowleri; this amoeba produces a fatal disease called primary amoebic meningoencephalitis. In the present study, we analyzed the electrophoretic pattern of the membrane proteins of N. fowleri and compared it with the nonpathogenic N. lovaniensis and N. gruberi. We detected a 23-kDa protein (Nf23) present at a higher level in N. fowleri than in the nonpathogenic amoebae. The mass spectrometry analysis showed that the Nf23 protein has a sequence of 229 amino acids that corresponds to a membrane protein. The mRNA level of nf23 was overexpressed 4-fold and 40,000-fold in N. fowleri compared with N. lovaniensis and N. gruberi, respectively. Moreover, we found a 5-fold overexpression of nf23 in N. fowleri trophozoites recovered from mouse brains compared with trophozoites axenically cultivated. In addition, the cytopathic effect on Madin-Darby Canine Kidney cells coincubated with N. fowleri diminished in the presence of antibodies against Nf23; nevertheless, the nonpathogenic amoebae did not produce damage to the monolayer cells. These results suggest that the plasma membrane protein Nf23 is probably involved in the virulence of N. fowleri.


Asunto(s)
Naegleria fowleri/metabolismo , Naegleria fowleri/patogenicidad , Naegleria/metabolismo , Naegleria/patogenicidad , Proteínas Protozoarias/metabolismo , Virulencia/genética , Animales , Encéfalo/metabolismo , Encéfalo/parasitología , Perros , Expresión Génica , Células de Riñón Canino Madin Darby , Ratones , Naegleria fowleri/genética , Proteínas Protozoarias/genética , Análisis de Secuencia de Proteína
18.
Artículo en Inglés | MEDLINE | ID: mdl-30520386

RESUMEN

BACKGROUND: Natural killer cells (NKC) are a major component of the innate immune response to HCV, mediating their effects through TRAIL and IFN-γ. However, their function is diminished in chronic HCV patients (HCVp). Prolactin is an immunomodulatory hormone capable of activating NKC. OBJECTIVE: The study aims to explore if hyperprolactinemia can activate NKC in HCVp. METHODS: We treated twelve chronic HCVp (confidence level =95%, power =80%) for 15 days with Levosulpiride plus Cimetidine to induce mild hyperprolactinemia. Before and after treatment, we determined TRAIL and NKG2D expression on peripheral blood NKC, along with cytokine profiles, viral loads and liver function. We also evaluated in vitro effects of prolactin and/or IL-2 on NKC TRAIL or NKG2D expression and IFN-γ levels on cultured blood mononuclear cells from 8 HCVp and 7 healthy controls. RESULTS: The treatment induced mild hyperprolactinemia and increased TRAIL expression on NKC as well as the secretion of IL-1ra, IL-2, PDGF and IFN-γ. Viral loads decreased in six HCVp. IL-2 and TRAIL together explained the viral load decrease. In vitro, prolactin plus IL-2 synergized to increase TRAIL and NKG2D expression on NKC from HCVp but not in controls. CONCLUSION: Levosulpiride/Cimetidine treatment induced mild hyperprolactinaemia that was associated with NKC activation and Th1-type cytokine profile. Also, an increase in TRAIL and IL-2 was associated with viral load decrease. This treatment could potentially be used to reactivate NKC in HCVp.


Asunto(s)
Hepatitis C Crónica/sangre , Hepatitis C Crónica/tratamiento farmacológico , Interleucina-2/biosíntesis , Células Asesinas Naturales/metabolismo , Prolactina/sangre , Ligando Inductor de Apoptosis Relacionado con TNF/biosíntesis , Células Cultivadas , Cimetidina/uso terapéutico , Cimetidina/toxicidad , Expresión Génica , Humanos , Hiperprolactinemia/sangre , Hiperprolactinemia/inducido químicamente , Interleucina-2/genética , Células Asesinas Naturales/efectos de los fármacos , Masculino , Prueba de Estudio Conceptual , Sulpirida/análogos & derivados , Sulpirida/uso terapéutico , Sulpirida/toxicidad , Ligando Inductor de Apoptosis Relacionado con TNF/genética , Carga Viral/efectos de los fármacos , Carga Viral/fisiología
19.
Rev. cientif. cienc. med ; 22(1): 24-28, 2019. ilus
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1098928

RESUMEN

Introducción: La diálisis peritoneal es un tratamiento ampliamente usado como terapia de sustitución renal en pacientes con Enfermedad Renal Crónica, Una de sus complicaciones más frecuentes es la peritonitis asociada a la mala técnica en la realización de la misma. Objetivo: Determinar la incidencia de peritonitis asociada a diálisis peritoneal en un hospital de segundo nivel del estado de Puebla, México. Material y Métodos: Estudio observacional, descriptivo, de corte transversal. Se revisaron expedientes de pacientes con diálisis peritoneal continua ambulatoria atendidos durante 2017 Resultados: En 2017 se atendieron 18 pacientes con el diagnóstico de peritonitis asociada a diálisis peritoneal. 11 hombres y siete mujeres con rango de edad fue de 20 a 71 años, La tasa de incidencia fue de 52 por cada 100 pacientes, la tasa de peritonitis fue de 1,33 episodios por paciente por año. Los síntomas presentes en los pacientes fueron dolor, líquido efluente turbio. La Nefropatía Diabética fue la primera causa de Enfermedad Renal Crónica en nuestra población. El agente etiológico más frecuente fue Staphylococcus aureus. El tiempo promedio para desarrollar peritonitis fue de 11,3 meses. Un paciente ameritó recambio de catéter con adecuada función y cinco pacientes cambiaron a modalidad de hemodiálisis. Conclusión: La tasa de incidencia de peritonitis asociada a diálisis peritoneal es mayor a la esperada. En la elección de la modalidad continua ambulatoria se debe insistir en la capacitación continua al paciente y cuidador para disminuir esta complicación.


Introduction: Peritoneal dialysis is a treatment widely used as a renal replacement therapy in patients with Chronic Kidney Disease, one of its most frequent complications is peritonitis associated mainly with poor technique in the realization of it. Objective: To determine the incidence of peritonitis associated with peritoneal dialysis in a second level hospital in the state of Puebla, Mexico. Material and Methods: An observational, descriptive, transectional study was conducted. We reviewed clinic files of patients who had renal replacement therapy as continuous ambulatory peritoneal dialysis attended in 2017. Results: In 2017, 18 patients were treated with a diagnosis of peritonitis associated with peritoneal dialysis. 11 men and seven women with an age range of 20 to 71 years.The incidence rate was 52 per 100 patients, the rate of peritonitis was 1,33 episodes per patient per year.The symptoms present in the patients were pain, cloudy effluent liquid.The main cause of Chronic Kidney Disease was diabetic nephropathy.The most frequent etiologic agent was Staphylococcus aureus. The average time to develop peritonitis was 11,3 months. One patient required catheter replacement with adequate function and five patients changed to hemodialysis. Conclusion: The incidence rate of peritonitis associated with peritoneal dialysis is high than expected. In the selection of continuous ambulatory peritoneal dialysis, continuous training for the patient and caregiver should be insisted on to decrease the frequency of this complication.

20.
Rev. cientif. cienc. med ; 22(1): 53-56, 2019. ilus
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1098933

RESUMEN

La Cromoblastomicosis es una micosis subcutánea producida por hongos melanizados conocidos como dematiáceos, comúnmente secundario a un proceso traumático previo. Actual mente la incidencia de esta patología es desconocida. Se presenta el caso de un hombre de 64 años originario de la comunidad de Coyomeapan, Puebla, México, quien acude por falta de cicatrización de una úlcera en hueco poplíteo derecho generada por quemadura con candil de petróleo hace cuatro años. Refiriendo dolor con leve dificultad para la deambulación y sin evidencia de sangrado activo. Se realiza raspado de la lesión con presencia de células fumagoides posteriormente se aisló Cladophialophora carrionii en Agar Boreli. Se inició tratamiento con terbinafina para su recuperación. El conocimiento de este tipo de micosis aumenta la posibilidad de un diagnóstico temprano y certero para evitar complicaciones derivadas de la cronicidad o retraso del diagnóstico.


Chromoblastomycosis is a subcutaneous mycosis produced by pigment-producing fungi known as dematiaceous, commonly after a previous traumatic process. Currently the incidence of this pathology is unknown. We present the case of a 64-year-old man from the community of Coyomeapan, Puebla, Mexico, who came for lack of healing of an ulcer in the right popliteal socket generated by burning with an oil lamp four years ago. Referring pain with mild difficulty in ambulation and without evidence of active bleeding. Scraping of the lesion was performed with the presence of fumagoid cells. Cladophialophora carrionii was isolated on Boreli Agar. Treatment was started with terbinafina for recovery. The knowledge of this type of mycosis increases the possibility of an early and accurate diagnosis to avoid complications derived from the chronicity or delay of the diagnosis.

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