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2.
Front Vet Sci ; 10: 1187271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396996

RESUMO

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.

3.
Cells ; 11(12)2022 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-35741012

RESUMO

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.


Assuntos
COVID-19 , Diabetes Mellitus Tipo 2 , Resistência à Insulina , COVID-19/complicações , Diabetes Mellitus Tipo 2/patologia , Humanos , Inflamação/patologia , Neutrófilos/patologia , Obesidade/patologia
4.
Biomed Res Int ; 2021: 1601565, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34604381

RESUMO

Trogocytosis is a general biological process that involves one cell physically taking small parts of the membrane and other components from another cell. In trogocytosis, one cell seems to take little "bites" from another cell resulting in multiple outcomes from these cell-cell interactions. Trogocytosis was first described in protozoan parasites, which by taking pieces of host cells, kill them and cause tissue damage. Now, it is known that this process is also performed by cells of the immune system with important consequences such as cell communication and activation, elimination of microbial pathogens, and even control of cancer cells. More recently, trogocytosis has also been reported to occur in cells of the central nervous system and in various cells during development. Some of the molecules involved in phagocytosis also participate in trogocytosis. However, the molecular mechanisms that regulate trogocytosis are still a mystery. Elucidating these mechanisms is becoming a research area of much interest. For example, why neutrophils can engage trogocytosis to kill Trichomonas vaginalis parasites, but neutrophils use phagocytosis to eliminate already death parasites? Thus, trogocytosis is a significant process in normal physiology that multiple cells from different organisms use in various scenarios of health and disease. In this review, we present the basic principles known on the process of trogocytosis and discuss the importance in this process to host-pathogen interactions and to normal functions in the immune and nervous systems.


Assuntos
Crescimento e Desenvolvimento , Imunidade , Sistema Nervoso/citologia , Trogocitose/imunologia , Animais , Bactérias/metabolismo , Morte Celular , Humanos
5.
J Extracell Vesicles ; 10(6): e12087, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33936570

RESUMO

The molecular characterization of extracellular vesicles (EVs) has revealed a great heterogeneity in their composition at a cellular and tissue level. Current isolation methods fail to efficiently separate EV subtypes for proteomic and functional analysis. The aim of this study was to develop a reproducible and scalable isolation workflow to increase the yield and purity of EV preparations. Through a combination of polymer-based precipitation and size exclusion chromatography (Pre-SEC), we analyzed two subsets of EVs based on their CD9, CD63 and CD81 content and elution time. EVs were characterized using transmission electron microscopy, nanoparticle tracking analysis, and Western blot assays. To evaluate differences in protein composition between the early- and late-eluting EV fractions, we performed a quantitative proteomic analysis of MDA-MB-468-derived EVs. We identified 286 exclusive proteins in early-eluting fractions and 148 proteins with a differential concentration between early- and late-eluting fractions. A density gradient analysis further revealed EV heterogeneity within each analyzed subgroup. Through a systems biology approach, we found significant interactions among proteins contained in the EVs which suggest the existence of functional clusters related to specific biological processes. The workflow presented here allows the study of EV subtypes within a single cell type and contributes to standardizing the EV isolation for functional studies.


Assuntos
Vesículas Extracelulares/classificação , Vesículas Extracelulares/metabolismo , Proteômica/métodos , Animais , Western Blotting/métodos , Cromatografia em Gel/métodos , Vesículas Extracelulares/química , Humanos , Microscopia Eletrônica de Transmissão/métodos , Polímeros/análise , Proteínas/análise
6.
Artigo em Inglês | MEDLINE | ID: mdl-30023352

RESUMO

Amoebiasis, the disease caused by Entamoeba histolytica is the third leading cause of human deaths among parasite infections. E. histolytica was reported associated with around 100 million cases of amoebic dysentery, colitis and amoebic liver abscess that lead to almost 50,000 fatalities worldwide in 2010. E. histolytica infection is associated with the induction of inflammation characterized by a large number of infiltrating neutrophils. These neutrophils have been implicated in defense against this parasite, by mechanisms not completely described. The neutrophil antimicrobial mechanisms include phagocytosis, degranulation, and formation of neutrophil extracellular traps (NETs). Recently, our group reported that NETs are also produced in response to E. histolytica trophozoites. But, the mechanism for NETs induction remains unknown. In this report we explored the possibility that E. histolytica leads to NETs formation via a signaling pathway similar to the pathways activated by PMA or the Fc receptor FcγRIIIb. Neutrophils were stimulated by E. histolytica trophozoites and the effect of various pharmacological inhibitors on amoeba-induced NETs formation was assessed. Selective inhibitors of Raf, MEK, and NF-κB prevented E. histolytica-induced NET formation. In contrast, inhibitors of PKC, TAK1, and NADPH-oxidase did not block E. histolytica-induced NETs formation. E. histolytica induced phosphorylation of ERK in a Raf and MEK dependent manner. These data show that E. histolytica activates a signaling pathway to induce NETs formation, that involves Raf/MEK/ERK, but it is independent of PKC, TAK1, and reactive oxygen species (ROS). Thus, amoebas activate neutrophils via a different pathway from the pathways activated by PMA or the IgG receptor FcγRIIIb.


Assuntos
Entamoeba histolytica/imunologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Armadilhas Extracelulares/metabolismo , Interações Hospedeiro-Patógeno , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Transdução de Sinais , Quinases raf/metabolismo , Humanos , Trofozoítos/imunologia
7.
Rev. odontol. mex ; 21(1): 40-48, ene.-mar. 2017. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-902717

RESUMO

Introducción: Existen diversos materiales de retroobturación, pero poco se sabe de su toxicidad sobre fibroblastos gingivales. Objetivo: Evaluar la citotoxicidad de tres materiales de retroobturación sobre fibroblastos gingivales humanos y fibroblastos de la línea L929. Material y métodos: Los medios condicionados de los materiales de retroobturación EndoSequence® BC RRMTM (ERRM), trióxido mineral agregado MTA Angelus® blanco (MTA) y material de restauración intermedia (IRM®) se obtuvieron en fresco, al tiempo de fraguado, y después de 1, 24 y 72 horas del tiempo de fraguado. La morfología celular fue evaluada por microscopia de luz y la viabilidad celular fue evaluada a través de la actividad metabólica mitocondrial con 3-(4,5-dimetiltiazol-2-il)-2,5-difenil bromuro de tetrazolio (MTT). El análisis estadístico se realizó por ANOVA. Resultados: El material ERRM no mostró efectos citotóxicos sobre los fibroblastos. Sin embargo, el MTA y el IRM® mostraron citotoxicidad moderada y alta, respectivamente. Esto revela que el MTA y el IRM® no son completamente inocuos. Conclusión: Los materiales biocerámicos como el ERRM pueden ser considerados los materiales de retroobturación más biocompatibles.


Introduction: Presently there are many retrofilling materials in themarket, nevertheless, little is known about their toxicity on gingival fibroblasts. Objective: To assess cytotoxicity of three materials tohuman gingival fibroblasts and L929 mouse fibroblasts cell line. Material and methods: EndoSequence® BC RRMTM (ERRM; rootrepair material), white MTA Angelus® (MTA) and intermediaterestoration material (IRM®) conditioned media were obtained whenmaterials were freshly mixed, at setting time and after 1, 24 and72 hours of setting time. Cell morphology was assessed with lightmicroscopy and cell viability was assessed through mitochondrialmetabolic activity with 3-(4,5-dimethylthiazole-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Statistical analysis was conducted withANOVA. Results: We found that ERRM material did not exhibitcytotoxic effects on used fibroblast, nevertheless, MTA and IRM® respectively exhibited moderate and severe cytotoxicity, thusindicating the materials were not fully harmless. Conclusion: Bioceramic cements like ERRM could be considered the mostcompatible retrofilling-materials.

8.
J Immunol Res ; 2016: 1396106, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27019855

RESUMO

Oral tissues are constantly exposed to damage from the mechanical effort of eating and to microorganisms, mostly bacteria. In healthy gingiva tissue remodeling and a balance between bacteria and innate immune cells are maintained. However, excess of bacteria biofilm (plaque) creates an inflammation state that recruits more immune cells, mainly neutrophils to the gingiva. Neutrophils create a barrier for bacteria to reach inside tissues. When neutrophils are insufficient, bacteria thrive causing more inflammation that has been associated with systemic effects on other conditions such as atherosclerosis, diabetes, and cancer. But paradoxically when neutrophils persist, they can also promote a chronic inflammatory state that leads to periodontitis, a condition that leads to damage of the bone-supporting tissues. In periodontitis, bone loss is a serious complication. How a neutrophil balance is needed for maintaining healthy oral tissues is the focus of this review. We present recent evidence on how alterations in neutrophil number and function can lead to inflammatory bone loss, and how some oral bacteria signal neutrophils to block their antimicrobial functions and promote an inflammatory state. Also, based on this new information, novel therapeutic approaches are discussed.


Assuntos
Neutrófilos/imunologia , Periodontite/imunologia , Perda do Osso Alveolar/etiologia , Perda do Osso Alveolar/imunologia , Perda do Osso Alveolar/microbiologia , Animais , Homeostase , Interações Hospedeiro-Patógeno , Humanos , Inflamação , Infiltração de Neutrófilos , Neutrófilos/fisiologia , Periodontite/microbiologia , Periodontite/terapia
9.
J Immunol Res ; 2015: 983698, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26819959

RESUMO

Neutrophils are the most abundant leukocytes in blood and are considered to be the first line of defense during inflammation and infections. In addition, neutrophils are also found infiltrating many types of tumors. Tumor-associated neutrophils (TANs) have relevant roles in malignant disease. Indeed neutrophils may be potent antitumor effector cells. However, increasing clinical evidence shows TANs correlate with poor prognosis. The tumor microenvironment controls neutrophil recruitment and in turn TANs help tumor progression. Hence, TANs can be beneficial or detrimental to the host. It is the purpose of this review to highlight these two sides of the neutrophil coin in cancer and to describe recent studies that provide some light on the mechanisms for neutrophil recruitment to the tumor, for neutrophils supporting tumor progression, and for neutrophil activation to enhance their antitumor functions.


Assuntos
Neoplasias/imunologia , Neutrófilos/imunologia , Animais , Carcinogênese , Movimento Celular , Humanos , Imunidade Celular , Microambiente Tumoral
10.
Rev. odontol. mex ; 17(3): 181-184, jul.-sept. 2013. ilus
Artigo em Espanhol | LILACS-Express | LILACS | ID: lil-714523

RESUMO

La rehabilitación de pacientes con secuelas de labio y paladar hendidos todavía sigue siendo un reto para los profesionales de la salud, tanto desde el punto de vista quirúrgico como del protésico. Estos pacientes necesitan de un tratamiento multidisciplinario que ofrezca la mejor alternativa de rehabilitación para el paciente. En este artículo presentamos la rehabilitación integral de un paciente con secuelas de labio y paladar hendidos (pérdida de la dimensión vertical, colapso nasal, defecto del labio superior, discrepancia del maxilar y la mandíbula, fístulas oro-antrales y ausencia de incisivos anteriores superiores) por medio de una sobredentadura modificada (sin hacer tratamiento endodóntico). El resultado estético y funcional con este tipo de tratamiento fue satisfactorio y se realizó en un periodo corto de tiempo.


Rehabilitation of patients suffering from cleft lip and palate surgery sequels is still a challenge for health professionals related to both surgical and prosthetic fields. These patients require a multi-disciplinary treatment able to offer the best possible rehabilitation alternative. The present article presents a case of total rehabilitation of a patient with sequels to cleft lip and palate surgery (loss of vertical dimension, nasal collapse, upper lip defect, upper and lower jaw discrepancies, oro-antral fistulae, absence of upper incisors) by means of a modified over-denture (with absence of endodontic treatment). Esthetic and functional results achieved with this treatment were satisfactory as well as achieved in a short period of time.

11.
Toxicol Sci ; 84(1): 157-66, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15601678

RESUMO

Inorganic arsenic exposure via drinking water has been associated with cancer and serious injury in various internal organs, as well as with peripheral neuropathy and diverse effects in the nervous system. Alterations in memory and attention processes have been reported in exposed children, whereas adults acutely exposed to high amounts of inorganic arsenic showed impairments in learning, memory, and concentration. Glutathione (GSH) is extensively involved in the metabolism of inorganic arsenic, and both arsenite and its methylated metabolites have been shown to be potent inhibitors of glutathione reductase (GR) in vitro. Brain would be more susceptible to GR inhibition because of the decreased activities of superoxide dismutase (SOD) and catalase reported in this tissue. To investigate whether GR inhibition could be documented in vivo, we determined the activity and levels of GR in brain as well as in liver, the main organ of arsenic metabolism in mice exposed to 2.5, 5, or 10 mg/kg/day of sodium arsenite over a period of 9 days. In contrast to what has been observed in vitro, significant inhibition of the expression and activity of GR was observed only at the highest concentration used (10 mg/kg/day) in both organs. Although the disposition of arsenicals was higher in liver, significant amounts of inorganic and methylated arsenic forms were determined in the brain of exposed animals. The formation of monomethylarsenic (MMA) and dimethylarsenic (DMA) metabolites in the brain was confirmed by incubating brain slices for 24, 48, and 72 h with sodium arsenite.


Assuntos
Arsenicais/farmacocinética , Encéfalo/metabolismo , Glutationa Redutase/antagonistas & inibidores , Fígado/metabolismo , Animais , Western Blotting , Relação Dose-Resposta a Droga , Glutationa/metabolismo , Masculino , Metilação , Camundongos , Técnicas de Cultura de Órgãos , Oxirredução , Tiorredoxinas/metabolismo , Vitaminas/metabolismo
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