Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 363.406
Filtrar
1.
Sci Total Environ ; 752: 142001, 2021 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32892057

RESUMEN

Generally, human oral exposure assessments of contaminants have not considered the absorption factor in the human gastrointestinal tract, thus overestimating human exposure and associated health risk. Currently, more researchers are adding the absorption factor into human exposure assessment, and bioaccessibility measured by in-vitro methods is generally replacing bioavailability for estimation because of the cheap and rapid determination. However, no single unified in-vitro method is used for bioaccessibility measurement of organic pollutants, although several methods have been developed for these pollutants and have shown good in vitro-in vivo correlation between bioaccessibility and bioavailability. The present review has focused on the development of in-vitro methods, validation of these methods through in-vivo assays, determination of factors influencing bioaccessibility, application of bioaccessibility in human exposure assessment, and the challenges faced. Overall, most in-vitro methods were validated using bioavailability, and better in vitro-in vivo correlations were obtained when absorption sinks were added to the digestion solution to mimic dynamic absorption of organic chemicals by small intestine. Incorporating bioaccessibility into the estimation of human exposure by oral ingestion significantly decreases the estimated exposure dose. However, more investigations on bioaccessibility of hydrophobic organic compounds are urgently needed because many challenges for in-vitro methods remain to be overcome.


Asunto(s)
Contaminantes Ambientales , Contaminantes del Suelo , Disponibilidad Biológica , Humanos , Técnicas In Vitro , Compuestos Orgánicos , Medición de Riesgo , Contaminantes del Suelo/análisis
2.
Molecules ; 25(21)2020 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-33142770

RESUMEN

In December 2019, a new severe acute respiratory syndrome coronavirus (SARS-CoV-2), causing coronavirus disease 2019 (COVID-19), emerged in Wuhan, China. Despite containment measures, SARS-CoV-2 spread in Asia, Southern Europe, then in America and currently in Africa. Identifying effective antiviral drugs is urgently needed. An efficient approach to drug discovery is to evaluate whether existing approved drugs can be efficient against SARS-CoV-2. Doxycycline, which is a second-generation tetracycline with broad-spectrum antimicrobial, antimalarial and anti-inflammatory activities, showed in vitro activity on Vero E6 cells infected with a clinically isolated SARS-CoV-2 strain (IHUMI-3) with median effective concentration (EC50) of 4.5 ± 2.9 µM, compatible with oral uptake and intravenous administrations. Doxycycline interacted both on SARS-CoV-2 entry and in replication after virus entry. Besides its in vitro antiviral activity against SARS-CoV-2, doxycycline has anti-inflammatory effects by decreasing the expression of various pro-inflammatory cytokines and could prevent co-infections and superinfections due to broad-spectrum antimicrobial activity. Therefore, doxycycline could be a potential partner of COVID-19 therapies. However, these results must be taken with caution regarding the potential use in SARS-CoV-2-infected patients: it is difficult to translate in vitro study results to actual clinical treatment in patients. In vivo evaluation in animal experimental models is required to confirm the antiviral effects of doxycycline on SARS-CoV-2 and more trials of high-risk patients with moderate to severe COVID-19 infections must be initiated.


Asunto(s)
Antivirales/farmacología , Betacoronavirus/efectos de los fármacos , Doxiciclina/farmacología , Animales , Antibacterianos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Chlorocebus aethiops , Cloroquina/farmacología , Técnicas In Vitro , Pruebas de Sensibilidad Microbiana , Células Vero
3.
J Toxicol Sci ; 45(11): 695-700, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33132243

RESUMEN

Coumarin is a dietary-derived substance that is extensively metabolized by human liver to excretable 7-hydroxycoumarin. Although coumarin under daily dietary consumption is generally regarded as nontoxic, the substance is of toxicological and clinical interest because of its potential association with hepatotoxicity, which is especially evident in rats. In this study, the pharmacokinetics of coumarin were modeled after virtual oral administration in humans. The adjusted monitoring equivalents of coumarin, along with the biotransformation of coumarin to o-hydroxyphenylacetic acid (via 3,4-epoxidation) based on reported plasma concentrations from rat studies, were scaled to human coumarin equivalents using known species allometric scaling factors. Using rat and human liver preparations, data on the rapid in vitro metabolic clearance for humans (~50-fold faster than in rats) were obtained for in vitro-in vivo extrapolation. For human physiologically based pharmacokinetic (PBPK) modeling, the metabolic ratios to o-hydroxyphenylacetic acid and 7-hydroxycoumarin were set at minor (0.1) and major (0.9) levels for the total disappearance of coumarin. The resulting modeled plasma concentration curves in humans generated by simple PBPK models were consistent with reported simulated coumarin maximum concentrations. These results provide basic information to simulate plasma levels of coumarin and its primary metabolite 7-hydroxycoumarin or its secondary activated metabolite o-hydroxyphenylacetic acid (via 3,4-epoxidation) resulting from dietary foodstuff consumption. Under the current assumptions, little toxicological impact of coumarin was evident in humans, thereby indicating the usefulness of forward dosimetry using PBPK modeling for human risk assessment.


Asunto(s)
Cumarinas/sangre , Cumarinas/toxicidad , Animales , Simulación por Computador , Cumarinas/metabolismo , Cumarinas/farmacocinética , Conjuntos de Datos como Asunto , Humanos , Técnicas In Vitro , Hígado/metabolismo , Masculino , Modelos Biológicos , Fenilacetatos/sangre , Ratas Sprague-Dawley , Medición de Riesgo , Umbeliferonas/sangre
4.
J Pharmacol Sci ; 144(4): 197-203, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33070838

RESUMEN

The role of cytoskeleton dynamics in the oxidative stress toward human vasculature has been unclear. The current study examined whether the cytoskeleton-disrupting agent cytochalasin B reduces oxidative stress caused by high glucose in the human arterial smooth muscle. All experiments in the human omental arteries without endothelium or the cultured human coronary artery smooth muscle cells were performed in d-glucose (5.5 mmol/L). The exposure toward d-glucose (20 mmol/L) for 60 min reduced the relaxation or hyperpolarization to an ATP sensitive K+ channel (KATP) opener levcromakalim (10-8 to 3 × 10-6 mol/L and 3 × 10-6 mol/L, respectively). Cytochalasin B and a superoxide inhibitor Tiron, restored them similarly. Cytochalasin B reduced the NADPH oxidase activity, leading to a decrease in superoxide levels of the arteries treated with high d-glucose. Also, cytochalasin B impaired the F-actin constitution and the membrane translocation of an NADPH oxidase subunit p47phox in artery smooth muscle cells treated with high d-glucose. A clinical concentration of cytochalasin B prevented human vascular smooth muscle malfunction via the oxidative stress caused by high glucose. Regulation of the cytoskeleton may be essential to keep the normal vascular function in patients with hyperglycemia.


Asunto(s)
Citocalasina B/farmacología , Citoesqueleto/metabolismo , Glucosa/efectos adversos , Hiperglucemia/metabolismo , Músculo Liso Vascular/metabolismo , Miocitos del Músculo Liso/metabolismo , Estrés Oxidativo/efectos de los fármacos , Adulto , Anciano , Células Cultivadas , Cromakalim/farmacología , Femenino , Humanos , Hiperglucemia/fisiopatología , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Relajación Muscular/efectos de los fármacos , NADPH Oxidasas/metabolismo , Superóxidos/metabolismo
5.
J Pharmacol Sci ; 144(4): 237-244, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33070843

RESUMEN

Hypoxic pulmonary hypertension (HPH) is a progressive and irreversible disease that reduces survival. Echinacoside is a phenylethanoid glycoside from Tibetan herbs known for its vasorelaxant effect and for inhibiting the proliferation of rat pulmonary arterial smooth muscle cells. This study aimed to investigate the effect of echinacoside on HPH. Sprague Dawley rats were housed in a hypobaric hypoxia chamber (4500 m) for 28 days to obtain the HPH model. Echinacoside (3.75, 7.5, 15, 30 and 40 mg/kg) was administered by intraperitoneal injection from the 1st to the 28th day. The mean pulmonary artery pressure (mPAP), right ventricular hypertrophy index, hemoglobin, hematocrit, red blood cell concentration and morphological change of pulmonary arteries were evaluated. Vascular perfusion assay was used to assess the pulmonary artery function. Echinacoside reduced mPAP, hemoglobin, hematocrit, right ventricular hypertrophy index and mean wall thickness% of pulmonary arteries in HPH rats. It significantly increased maximum vasoconstriction percentage of pulmonary arteries induced by noradrenaline in a dose-dependent manner. In addition, it improved the responsiveness of pulmonary arteries to acetylcholine and sodium nitroprusside. Therefore, Echinacoside might be an effective treatment against HPH, since it regulated pulmonary artery endothelium and smooth muscle layer function and improved the remodeling of pulmonary artery.


Asunto(s)
Glicósidos/administración & dosificación , Glicósidos/farmacología , Hipertensión Pulmonar/tratamiento farmacológico , Hipertensión Pulmonar/etiología , Hipoxia/complicaciones , Fitoterapia , Arteria Pulmonar/efectos de los fármacos , Arteria Pulmonar/fisiopatología , Remodelación Vascular/efectos de los fármacos , Vasoconstricción/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Glicósidos/uso terapéutico , Hipertensión Pulmonar/fisiopatología , Hipertensión Pulmonar/prevención & control , Técnicas In Vitro , Inyecciones Intraperitoneales , Masculino , Ratas Sprague-Dawley , Vasodilatadores
6.
Nature ; 585(7825): 426-432, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32908310

RESUMEN

Endothelial cells adopt tissue-specific characteristics to instruct organ development and regeneration1,2. This adaptability is lost in cultured adult endothelial cells, which do not vascularize tissues in an organotypic manner. Here, we show that transient reactivation of the embryonic-restricted ETS variant transcription factor 2 (ETV2)3 in mature human endothelial cells cultured in a serum-free three-dimensional matrix composed of a mixture of laminin, entactin and type-IV collagen (LEC matrix) 'resets' these endothelial cells to adaptable, vasculogenic cells, which form perfusable and plastic vascular plexi. Through chromatin remodelling, ETV2 induces tubulogenic pathways, including the activation of RAP1, which promotes the formation of durable lumens4,5. In three-dimensional matrices-which do not have the constraints of bioprinted scaffolds-the 'reset' vascular endothelial cells (R-VECs) self-assemble into stable, multilayered and branching vascular networks within scalable microfluidic chambers, which are capable of transporting human blood. In vivo, R-VECs implanted subcutaneously in mice self-organize into durable pericyte-coated vessels that functionally anastomose to the host circulation and exhibit long-lasting patterning, with no evidence of malformations or angiomas. R-VECs directly interact with cells within three-dimensional co-cultured organoids, removing the need for the restrictive synthetic semipermeable membranes that are required for organ-on-chip systems, therefore providing a physiological platform for vascularization, which we call 'Organ-On-VascularNet'. R-VECs enable perfusion of glucose-responsive insulin-secreting human pancreatic islets, vascularize decellularized rat intestines and arborize healthy or cancerous human colon organoids. Using single-cell RNA sequencing and epigenetic profiling, we demonstrate that R-VECs establish an adaptive vascular niche that differentially adjusts and conforms to organoids and tumoroids in a tissue-specific manner. Our Organ-On-VascularNet model will permit metabolic, immunological and physiochemical studies and screens to decipher the crosstalk between organotypic endothelial cells and parenchymal cells for identification of determinants of endothelial cell heterogeneity, and could lead to advances in therapeutic organ repair and tumour targeting.


Asunto(s)
Vasos Sanguíneos/citología , Carcinogénesis , Células Endoteliales/citología , Hemodinámica , Neoplasias/irrigación sanguínea , Organogénesis , Organoides/irrigación sanguínea , Vasos Sanguíneos/crecimiento & desarrollo , Técnicas de Cultivo de Célula/instrumentación , Técnicas de Cultivo de Célula/métodos , Cromatina/metabolismo , Epigénesis Genética , Epigenómica , Células Endoteliales de la Vena Umbilical Humana , Humanos , Técnicas In Vitro , Islotes Pancreáticos/irrigación sanguínea , Modelos Biológicos , Especificidad de Órganos , RNA-Seq , Análisis de la Célula Individual , Factores de Transcripción , Transcriptoma
7.
PLoS One ; 15(9): e0239479, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32966310

RESUMEN

Mycotoxin management in agriculture is an essential challenge for maintaining the health of both animals and humans. Choosing the right adsorbent is still a question for many breeders and an important criterion for feed manufacturers. New adsorbents are still being sought. Graphene oxide is a promising material in the field of nanotechnology, which excels in its adsorption properties. Presented in vitro study investigates graphene oxide for the binding of mycotoxins from crushed wheat. The results show that graphene oxide has an adsorption capacity for aflatoxin 0.045 mg/g, zearalenone 0.53 mg/g and deoxynivalenol 1.69 mg/g at 37° C. In vitro simulation of crushed wheat digestion showed rapid adsorption during the gastric phase. Of the minerals, Mg, Cu and Zn were the most adsorbed. The applied dose of graphene oxide of 10 mg/g caused only a slight inhibition of the digestive enzymes α-amylase and trypsin compared to pepsin and gastric lipase. In vitro results indicated the suitability of graphene oxide in the adsorption of the aflatoxin, zearalenone and deoxynivalenol.


Asunto(s)
Grafito/química , Micotoxinas/aislamiento & purificación , Adsorción , Aflatoxina B1/aislamiento & purificación , Aflatoxina B1/toxicidad , Alimentación Animal/análisis , Alimentación Animal/toxicidad , Animales , Digestión , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Absorción Gastrointestinal , Humanos , Técnicas In Vitro , Micotoxinas/toxicidad , Nanoestructuras/química , Tricotecenos/aislamiento & purificación , Tricotecenos/toxicidad , Triticum/química , Triticum/toxicidad , Zearalenona/aislamiento & purificación , Zearalenona/toxicidad
8.
PLoS One ; 15(9): e0239540, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32966316

RESUMEN

Aflatoxin B1 (AFB1), a mycotoxin, is acutely hepatotoxic to many animals including humans. However, there are marked interspecies differences in sensitivity to AFB1-induced toxicity depending on bioactivation by cytochrome P450s (CYPs). In the present study, we examined the applicability of chimeric mice with humanized livers and derived fresh human hepatocytes for in vivo and vitro studies on AFB1 cytotoxicity to human hepatocytes. Chimeric mice with highly humanized livers and SCID mice received daily injections of vehicle (corn oil), AFB1 (3 mg/kg), and carbon tetrachloride (50 mg/kg) for 2 days. Histological analysis revealed that AFB1 promoted hepatocyte vacuolation and inflammatory cell infiltration in the area containing human hepatocytes. A novel human alanine aminotransferase 1 specific enzyme-linked immunosorbent assay demonstrated the acute toxicity of AFB1 to human hepatocytes in the chimeric mouse livers. The sensitivity of cultured fresh human hepatocytes isolated from the humanized liver mice for AFB1 cytotoxicity was comparable to that of primary human hepatocytes. Long-term exposure to AFB1 (6 or 14 days) produced a more severe cytotoxicity. The half-maximal lethal concentration was 10 times lower in the 2-week treatment than after 2 days of exposure. Lastly, the significant reduction of AFB1 cytotoxicity by a pan-CYP inhibitor or transfection with CYP3A4 specific siRNA clearly suggested that bioactivation of AFB1 catalyzed by CYPs was essential for AFB1 cytotoxicity to the human hepatocytes in our mouse model. Collectively, our results implicate the humanized liver mice and derived fresh human hepatocytes are useful models for studies of AFB1 cytotoxicity to human hepatocytes.


Asunto(s)
Aflatoxina B1/toxicidad , Hepatocitos/efectos de los fármacos , Activación Metabólica , Aflatoxina B1/administración & dosificación , Aflatoxina B1/farmacocinética , Animales , Citocromo P-450 CYP3A/genética , Citocromo P-450 CYP3A/metabolismo , Inhibidores Enzimáticos del Citocromo P-450/farmacología , Sistema Enzimático del Citocromo P-450/metabolismo , Hepatocitos/patología , Hepatocitos/trasplante , Humanos , Técnicas In Vitro , Dosificación Letal Mediana , Trasplante de Hígado , Masculino , Ratones , Ratones SCID , ARN Interferente Pequeño/genética , Quimera por Trasplante , Vacuolas/efectos de los fármacos , Vacuolas/patología
9.
PLoS One ; 15(9): e0239584, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32966331

RESUMEN

Familial forms of Alzheimer's disease (AD) are caused by mutations in the presenilin genes or in the gene encoding for the amyloid precursor protein (APP). Proteolytic cleavage of APP generates the ß-amyloid peptide (Aß), which aggregates into amyloid plaques, one of the major hallmarks of AD. APP mutations within the Aß sequence, so-called intra-Aß mutations, cluster around position E693 of APP, which corresponds to position E22 in the Aß sequence. One of these mutations is the Osaka mutation, E693Δ, which has unique aggregation properties with patients showing unusually low brain amyloid levels on amyloid PET scans. Despite intense research on the pathomechanisms of different intra-Aß mutants, our knowledge is limited due to controversial findings in various studies. Here, we investigated in an ex vivo experimental system the neuro- and synaptotoxic properties of two intra-Aß mutants with different intrinsic aggregation propensities, the Osaka mutation E22Δ and the Arctic mutation E22G, and compared them to wild-type (wt) Aß. Experiments in hippocampal slice cultures from transgenic mice were complemented by treating wild-type slices with recombinantly produced Aß40 or Aß42 containing the respective intra-Aß mutations. Our analyses revealed that wt Aß and E22G Aß, both recombinant and transgenic, caused a loss of dendritic spines along with an increase in tau phosphorylation and tau-dependent neurodegeneration. In all experiments, the 42-residue variants of wt and E22G Aß showed stronger effects than the respective Aß40 isoforms. In contrast, E22Δ Aß neither reduced dendritic spine density nor resulted in increased tau phosphorylation or neuronal cell death in our ex vivo system. Our findings suggest that the previously reported major differences in the aggregation kinetics between E22G and E22Δ Aß are likely reflected in different disease pathomechanisms.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/genética , Proteínas Mutantes/genética , Mutación , Proteínas tau/metabolismo , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/química , Péptidos beta-Amiloides/metabolismo , Animales , Muerte Celular , Espinas Dendríticas/patología , Hipocampo/metabolismo , Hipocampo/patología , Humanos , Técnicas In Vitro , Cinética , Ratones , Ratones Transgénicos , Proteínas Mutantes/química , Proteínas Mutantes/metabolismo , Neuronas/metabolismo , Neuronas/patología , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Fosforilación , Agregación Patológica de Proteínas/genética , Agregación Patológica de Proteínas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Sinapsis/patología
10.
PLoS One ; 15(9): e0239544, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32966339

RESUMEN

Injection laryngoplasty (IL) has been used to treat various types of glottal insufficiency. The precise volume and location of the injected materials impact the outcomes. However, exactly how increasing volumes of material are distributed is unknown. In fact, the amount of IL material required to medialize a vocal cord tends to be determined empirically. Thus, the goal of this study was to investigate the pattern of IL material distribution by checking serial micro-computed tomography (MCT) and pressure changes during ILs. This experimental study used 10 excised canine larynges. Experimental devices included the IL syringe, pressure sensor, infusion pump, fixed frame, and monitoring system. We injected calcium hydroxyapatite in the thyroarytenoid muscle; whenever 0.1 mL of material was injected, we obtained an MCT scan while simultaneously measuring the pressure. After the experiments, we performed histologic analyses. MCT analyses showed that materials initially expanded centrifugally and then expanded in all directions within the muscle. The pressure initially increased rapidly but then remained relatively constant until the point at which the materials expanded in multiple directions. Histologic analyses showed that the IL material tended to expand within the epimysium of the thyroarytenoid muscle. However, in some cases, the MCT revealed that there were leakages to the surrounding space with a corresponding pressure drop. If the IL material passes through the epimysium, leakage can occur in the surrounding space, which can account for the reduction in resistance during ILs.


Asunto(s)
Laringoplastia/métodos , Animales , Materiales Biocompatibles/administración & dosificación , Perros , Durapatita/administración & dosificación , Técnicas In Vitro , Inyecciones/efectos adversos , Inyecciones/instrumentación , Inyecciones/métodos , Músculos Laríngeos/diagnóstico por imagen , Músculos Laríngeos/cirugía , Laringe/diagnóstico por imagen , Laringe/cirugía , Modelos Animales , Presión , Pliegues Vocales/diagnóstico por imagen , Pliegues Vocales/cirugía , Microtomografía por Rayos X
11.
Lima; Perú. Ministerio de Salud; 20200900. 10 p.
Monografía en Español | LILACS, MINSAPERÚ | ID: biblio-1118773

RESUMEN

El documento contiene las pautas para garantizar la seguridad, calidad y desempeño en el desarrollo y validación de proyectos de investigación vinculados a los dispositivos de diagnóstico in vitro (DMDIVD), que permitan una autorización para la fabricación y uso.


Asunto(s)
Investigación , Proyectos de Investigación , Técnicas In Vitro , Infecciones por Coronavirus , Diagnóstico , Equipos y Suministros
12.
PLoS One ; 15(9): e0238425, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32960889

RESUMEN

OBJECTIVE: To evaluate the effects of Bifidobacterium animalis subsp. lactis HN019 (HN019) on clinical periodontal parameters (plaque accumulation and gingival bleeding), on immunocompetence of gingival tissues [expression of beta-defensin (BD)-3, toll-like receptor 4 (TLR4), cluster of differentiation(CD)-57 and CD-4], and on immunological properties of saliva (IgA levels) in non-surgical periodontal therapy in generalized chronic periodontitis (GCP) patients. Adhesion to buccal epithelial cells (BEC) and the antimicrobial properties of HN019 were also investigated. MATERIALS AND METHODS: Thirty patients were recruited and monitored clinically at baseline (before scaling and root planing-SRP) and after 30 and 90 days. Patients were randomly assigned to Test (SRP+Probiotic, n = 15) or Control (SRP+Placebo, n = 15) group. Probiotic lozenges were used for 30 days. Gingival tissues and saliva were immunologically analyzed. The adhesion of HN019 with or without Porphyromonas gingivalis in BEC and its antimicrobial properties were investigated in in vitro assays. Data were statistically analyzed (p<0.05). RESULTS: Test group presented lower plaque index (30 days) and lower marginal gingival bleeding (90 days) when compared with Control group. Higher BD-3, TLR4 and CD-4 expressions were observed in gingival tissues in Test group than in Control group. HN019 reduced the adhesion of P. gingivalis to BEC and showed antimicrobial potential against periodontopathogens. CONCLUSION: Immunological and antimicrobial properties of B. lactis HN019 make it a potential probiotic to be used in non-surgical periodontal therapy of patients with GCP. CLINICAL RELEVANCE: B. lactis HN019 may be a potential probiotic to improve the effects of non-surgical periodontal therapy. Name of the registry and registration number (ClinicalTrials.gov): "Effects of probiotic therapy in the treatment of periodontitis"-NCT03408548.


Asunto(s)
Bifidobacterium animalis/inmunología , Periodontitis Crónica/terapia , Probióticos/uso terapéutico , Adulto , Adhesión Bacteriana/inmunología , Infecciones por Bacteroidaceae/inmunología , Infecciones por Bacteroidaceae/microbiología , Infecciones por Bacteroidaceae/terapia , Periodontitis Crónica/inmunología , Periodontitis Crónica/microbiología , Método Doble Ciego , Femenino , Interacciones Microbiota-Huesped/inmunología , Humanos , Inmunoglobulina A Secretora/metabolismo , Técnicas In Vitro , Masculino , Persona de Mediana Edad , Mucosa Bucal/inmunología , Mucosa Bucal/microbiología , Porphyromonas gingivalis/patogenicidad , Saliva/inmunología
13.
J Oleo Sci ; 69(9): 1061-1075, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32879197

RESUMEN

Our previous studies have shown that α-eleostearic acid (α-ESA; cis-9, trans-11, trans-13 (c9,t11,t13)-conjugated linolenic acid (CLnA)) is converted into c9,t11-conjugated linoleic acid (CLA) in rats. Furthermore, we have demonstrated that the conversion of α-ESA into CLA is a nicotinamide adenine dinucleotide phosphate (NADPH)-dependent enzymatic reaction, which occurs mostly in the rat liver. However, the precise metabolic pathway and enzyme involved have not been identified yet. Therefore, in this study we aimed to determine the role of cytochrome P450 (CYP) in the conversion of α-ESA into c9,t11-CLA using an in vitro reconstitution system containing mouse hepatic microsomes, NADPH, and α-ESA. The CYP4 inhibitors, 17-ODYA and HET0016, performed the highest level of inhibition of CLA formation. Furthermore, the redox partner cytochrome P450 reductase (CPR) inhibitor, 2-chloroethyl ethyl sulfide (CEES), also demonstrated a high level of inhibition. Thus, these results indicate that the NADPH-dependent CPR/CYP4 system is responsible for CLA formation. In a correlation analysis between the specific activity of CLA formation and Cyp4 family gene expression in tissues, Cyp4a14 and Cyp4f13 demonstrated the best correlations. However, the CYP4F substrate prostaglandin A1 (PGA1) exhibited the strongest inhibitory effect on CLA formation, while the CYP4A and CYP4B1 substrate lauric acid had no inhibitory effect. Therefore, we conclude that the CYP4F13 enzyme is the major enzyme involved in CLA formation. This pathway is a novel pathway for endogenous CLA synthesis, and this study provides insight into the potential application of CLnA in functional foods.


Asunto(s)
Familia 4 del Citocromo P450/farmacología , Ácidos Linoleicos Conjugados/metabolismo , Ácidos Linolénicos/metabolismo , Microsomas Hepáticos/metabolismo , Animales , Familia 4 del Citocromo P450/genética , Familia 4 del Citocromo P450/metabolismo , Familia 4 del Citocromo P450/fisiología , Expresión Génica , Técnicas In Vitro , Ratones Endogámicos ICR , NADP/metabolismo
14.
J Oleo Sci ; 69(9): 1107-1115, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32879198

RESUMEN

Medicinal plants and their secondary metabolites have long been a rich source of biologically active compounds that can prevent many diseases. In this context, we investigated the antioxidant activities of the essential oil of Lavandula officinalis and tested its potency against hepatic and renal toxicity induced by hydrogen peroxide in adult male mice based on measurements of biochemical parameters, oxidative stress, and tissue damage in both organs. We proved a remarkable antioxidant power of this plant (in vitro) by correcting the harmful effects of the prooxidant (in vivo). It can be concluded that lavender is an aromatic plant capable of reducing the stress caused by reactive oxygen species.


Asunto(s)
Lesión Renal Aguda/inducido químicamente , Lesión Renal Aguda/tratamiento farmacológico , Antioxidantes , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Peróxido de Hidrógeno/toxicidad , Lavandula/química , Aceites Volátiles/farmacología , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Hojas de la Planta/química , Animales , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Femenino , Técnicas In Vitro , Masculino , Ratones , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/uso terapéutico , Especies Reactivas de Oxígeno/metabolismo
15.
PLoS Biol ; 18(9): e3000873, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32966273

RESUMEN

The inhibitory axonless olfactory bulb granule cells form reciprocal dendrodendritic synapses with mitral and tufted cells via large spines, mediating recurrent and lateral inhibition. As a case in point for dendritic transmitter release, rat granule cell dendrites are highly excitable, featuring local Na+ spine spikes and global Ca2+- and Na+-spikes. To investigate the transition from local to global signaling, we performed holographic, simultaneous 2-photon uncaging of glutamate at up to 12 granule cell spines, along with whole-cell recording and dendritic 2-photon Ca2+ imaging in acute juvenile rat brain slices. Coactivation of less than 10 reciprocal spines was sufficient to generate diverse regenerative signals that included regional dendritic Ca2+-spikes and dendritic Na+-spikes (D-spikes). Global Na+-spikes could be triggered in one third of granule cells. Individual spines and dendritic segments sensed the respective signal transitions as increments in Ca2+ entry. Dendritic integration as monitored by the somatic membrane potential was mostly linear until a threshold number of spines was activated, at which often D-spikes along with supralinear summation set in. As to the mechanisms supporting active integration, NMDA receptors (NMDARs) strongly contributed to all aspects of supralinearity, followed by dendritic voltage-gated Na+- and Ca2+-channels, whereas local Na+ spine spikes, as well as morphological variables, barely mattered. Because of the low numbers of coactive spines required to trigger dendritic Ca2+ signals and thus possibly lateral release of GABA onto mitral and tufted cells, we predict that thresholds for granule cell-mediated bulbar lateral inhibition are low. Moreover, D-spikes could provide a plausible substrate for granule cell-mediated gamma oscillations.


Asunto(s)
Potenciales de Acción , Señalización del Calcio , Dendritas/metabolismo , Bulbo Olfatorio/metabolismo , Sodio/metabolismo , Animales , Calcio/metabolismo , Femenino , Holografía , Técnicas In Vitro , Masculino , Ratas Wistar , Receptores de N-Metil-D-Aspartato/metabolismo
16.
PLoS One ; 15(9): e0238790, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32903275

RESUMEN

The potential mechanical impact of different rotary systems used for root canal preparation has been a matter of debate for long. The aim of this study was to explore the incidence of dentinal cracks after root canal instrumentation with various rotary systems, in vitro. One hundred and eighty intact lower central incisors were selected and randomly divided into fourteen treatment groups (n = 12/group) and a control group (n = 12). After decoronation, the root canals were instrumented with fourteen different rotary systems (E3, E3 azure, NT2, Hyflex CM, Hyflex EDM, 2Shape, OneCurve, ProTaper Next, ProTaper Gold, WaveOne Gold, Mtwo, Reciproc Blue, TF adaptive, K3XF). All roots were horizontally sectioned at 3, 6, and 9 mm from the apex with a low-speed saw under water-cooling. The slices were then examined under stereomicroscope for dentinal cracks. No cracks were found in the control group. Cracks were found in all treatment groups, predominantly in the 3 mm slices. There was no statistically significant difference in the number of cracks when comparing the different systems to each other at any section level. At 3 mm, however, five of the studied systems, namely K3XF (p = 0.004), Protaper Next (p = 0.001), Reciproc Blue (p<0.001), TF adaptive (p = 0.050), and 2Shape (p = 0.009) presented a significantly higher number of cracks than the control group. Within the limitations of this study, instrumented canals presented dentinal cracks, while uninstrumented ones presented no cracks after sectioning. There seems to be no significant difference among the tested systems regarding crack formation in the instrumented root canal wall. Crack formation occurred irrespective of the motion of the rotary system (rotational or reciprocation). Further studies are needed to clarify the factors that contribute to crack formation in the case of each individual rotary system.


Asunto(s)
Níquel , Preparación del Conducto Radicular/instrumentación , Titanio , Aleaciones Dentales , Dentina/lesiones , Diseño de Equipo , Humanos , Técnicas In Vitro , Tratamiento del Conducto Radicular/métodos
17.
Nat Commun ; 11(1): 4454, 2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32901001

RESUMEN

Chronic viral infections are often associated with impaired CD8+ T cell function, referred to as exhaustion. Although the molecular and cellular circuits involved in CD8+ T cell exhaustion are well defined, with sustained presence of antigen being one important parameter, how much T cell receptor (TCR) signaling is actually ongoing in vivo during established chronic infection is unclear. Here, we characterize the in vivo TCR signaling of virus-specific exhausted CD8+ T cells in a mouse model, leveraging TCR signaling reporter mice in combination with transcriptomics. In vivo signaling in exhausted cells is low, in contrast to their in vitro signaling potential, and despite antigen being abundantly present. Both checkpoint blockade and adoptive transfer of naïve target cells increase TCR signaling, demonstrating that engagement of co-inhibitory receptors curtails CD8+ T cell signaling and function in vivo.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Coriomeningitis Linfocítica/inmunología , Receptores de Antígenos de Linfocitos T/inmunología , Traslado Adoptivo , Animales , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Linfocitos T CD8-positivos/virología , Enfermedad Crónica , Citotoxicidad Inmunológica , Modelos Animales de Enfermedad , Regulación hacia Abajo , Tolerancia Inmunológica , Inmunidad Celular , Técnicas In Vitro , Activación de Linfocitos , Coriomeningitis Linfocítica/genética , Virus de la Coriomeningitis Linfocítica/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/inmunología , Receptor de Muerte Celular Programada 1/inmunología , RNA-Seq , Transducción de Señal/inmunología
18.
Nat Commun ; 11(1): 4457, 2020 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-32901017

RESUMEN

Innate lymphoid cells (ILCs) and CD4+ T cells produce IL-22, which is critical for intestinal immunity. The microbiota is central to IL-22 production in the intestines; however, the factors that regulate IL-22 production by CD4+ T cells and ILCs are not clear. Here, we show that microbiota-derived short-chain fatty acids (SCFAs) promote IL-22 production by CD4+ T cells and ILCs through G-protein receptor 41 (GPR41) and inhibiting histone deacetylase (HDAC). SCFAs upregulate IL-22 production by promoting aryl hydrocarbon receptor (AhR) and hypoxia-inducible factor 1α (HIF1α) expression, which are differentially regulated by mTOR and Stat3. HIF1α binds directly to the Il22 promoter, and SCFAs increase HIF1α binding to the Il22 promoter through histone modification. SCFA supplementation enhances IL-22 production, which protects intestines from inflammation. SCFAs promote human CD4+ T cell IL-22 production. These findings establish the roles of SCFAs in inducing IL-22 production in CD4+ T cells and ILCs to maintain intestinal homeostasis.


Asunto(s)
Ácidos Grasos Volátiles/inmunología , Microbioma Gastrointestinal/inmunología , Inmunidad Innata , Interleucinas/biosíntesis , Animales , Butiratos/inmunología , Butiratos/metabolismo , Butiratos/farmacología , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/microbiología , Citrobacter rodentium , Colitis/inmunología , Colitis/microbiología , Colitis/prevención & control , Infecciones por Enterobacteriaceae/inmunología , Infecciones por Enterobacteriaceae/microbiología , Infecciones por Enterobacteriaceae/prevención & control , Ácidos Grasos Volátiles/metabolismo , Ácidos Grasos Volátiles/farmacología , Microbioma Gastrointestinal/fisiología , Inhibidores de Histona Desacetilasas/farmacología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Técnicas In Vitro , Interleucinas/deficiencia , Interleucinas/genética , Linfocitos/efectos de los fármacos , Linfocitos/inmunología , Linfocitos/microbiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratones Transgénicos , Regiones Promotoras Genéticas , Receptores de Hidrocarburo de Aril/metabolismo , Receptores Acoplados a Proteínas G/metabolismo
19.
PLoS One ; 15(9): e0238948, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32915925

RESUMEN

Several equids have gone extinct and many extant equids are currently considered vulnerable to critically endangered. This work aimed to evaluate whether domestic horse oocytes support preimplantation development of zebra embryos obtained by intracytoplasmic sperm injection (ICSI, zebroid) and cloning, and to study the Hippo signaling pathway during the lineage specification of trophectoderm cells and inner cell mass cells. We first showed that zebra and horse sperm cells induce porcine oocyte activation and recruit maternal SMARCA4 during pronuclear formation. SMARCA4 recruitment showed to be independent of the genetic background of the injected sperm. No differences were found in blastocyst rate of ICSI hybrid (zebra spermatozoon into horse egg) embryos relative to the homospecific horse control group. Interestingly, zebra cloned blastocyst rate was significantly higher at day 8. Moreover, most ICSI and cloned horse and zebra blastocysts showed a similar expression pattern of SOX2 and nuclear YAP1 with the majority of the nuclei positive for YAP1, and most SOX2+ nuclei negative for YAP1. Here we demonstrated that horse oocytes support zebra preimplantation development of both, ICSI and cloned embryos, without compromising development to blastocyst, blastocyst cell number neither the expression of SOX2 and YAP1. Our results support the use of domestic horse oocytes as a model to study in vitro zebra embryos on behalf of preservation of valuable genetic.


Asunto(s)
Desarrollo Embrionario , Equidae/embriología , Equidae/genética , Caballos/fisiología , Oocitos/fisiología , Proteínas Adaptadoras Transductoras de Señales/genética , Animales , Núcleo Celular/fisiología , Clonación de Organismos/veterinaria , Citoplasma/fisiología , Técnicas de Cultivo de Embriones/veterinaria , Desarrollo Embrionario/genética , Desarrollo Embrionario/fisiología , Especies en Peligro de Extinción , Equidae/metabolismo , Femenino , Perfilación de la Expresión Génica , Caballos/genética , Técnicas In Vitro , Masculino , Técnicas de Transferencia Nuclear/veterinaria , Factores de Transcripción SOXB1/genética , Inyecciones de Esperma Intracitoplasmáticas/veterinaria , Sus scrofa
20.
PLoS One ; 15(9): e0238860, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32916695

RESUMEN

The presence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli on poultry products is an important issue for veterinary and human health due to the zoonotic infection risk for producers and consumers. The present study focuses on testing the efficacy of six different disinfection methods on eggshell samples, aiming to reduce ESBL producing E. coli contamination on the hatching egg. Sterile eggshell cutouts were artificially contaminated with 108 cfu/ml CTX-M-1 producing E. coli and used as a carrier model to analyze the efficacy of six disinfection methods. The contaminated samples were separated into two groups; 1) contaminated and disinfected, 2) contaminated and non-disinfected. Six independent disinfection protocols were performed following product specifications and protocols. Each eggshell sample was separately crushed, and the total viable bacterial count was calculated to determine the disinfection efficacy. Five out of six tested methods (formaldehyde gassing, hydrogen peroxide + alcohol spray, essential oils spray, peracetic acid foam, and low energetic electron radiation) demonstrated a reduction or completely eliminated the initial ESBL producing E. coli contamination. One method (essential oils as cold fog) only partly reached the expected efficacy threshold (reduction of >102 cfu/ml) and the result differed significantly when compared to the reference method i.e. formaldehyde gassing.


Asunto(s)
Desinfectantes/farmacología , Desinfección/clasificación , Desinfección/métodos , Cáscara de Huevo/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Escherichia coli/enzimología , beta-Lactamasas/metabolismo , Animales , Cáscara de Huevo/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/aislamiento & purificación , Infecciones por Escherichia coli/metabolismo , Infecciones por Escherichia coli/microbiología , Humanos , Técnicas In Vitro
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA