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1.
Int J Mol Sci ; 25(3)2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38338771

RESUMEN

Dichlorodiphenyltrichloroethane (DDT) is a wide-spread systemic pollutant with endocrine disrupting properties. Prenatal exposure to low doses of DDT has been shown to affect adrenal medulla growth and function. The role of postnatal exposure to DDT in developmental disorders remains unclear. The aim of the present investigation is to assess growth parameters and the expression of factors mediating the function and renewal of chromaffin cells in the adult adrenal medulla of male Wistar rats exposed to the endocrine disruptor o,p'-DDT since birth until sexual maturation. The DDT-exposed rats exhibited normal growth of the adrenal medulla but significantly decreased tyrosine hydroxylase production by chromaffin cells during postnatal period. Unlike the control, the exposed rats showed enhanced proliferation and reduced expression of nuclear ß-catenin, transcription factor Oct4, and ligand of Sonic hedgehog after termination of the adrenal growth period. No expression of pluripotency marker Sox2 and absence of Ascl 1-positive progenitors were found in the adrenal medulla during postnatal ontogeny of the exposed and the control rats. The present findings indicate that an increase in proliferative activity and inhibition of the formation of reserve for chromaffin cell renewal, two main mechanisms for cell maintenance in adrenal medulla, in the adult DDT-exposed rats may reflect a compensatory reaction aimed at the restoration of catecholamine production levels. The increased proliferation of chromaffin cells in adults suggests excessive growth of the adrenal medulla. Thus, postnatal exposure to DDT alters cell physiology and increases the risk of functional insufficiency and hyperplasia of the adrenal medulla.


Asunto(s)
Médula Suprarrenal , Células Cromafines , Disruptores Endocrinos , Embarazo , Femenino , Ratas , Animales , Masculino , Ratas Wistar , Disruptores Endocrinos/toxicidad , DDT/toxicidad , Proteínas Hedgehog , Fenómenos Fisiológicos Celulares
2.
Int J Mol Sci ; 24(7)2023 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-37047776

RESUMEN

Deuterium, a stable isotope of hydrogen, is abundant in organisms. It is known to produce various biological effects. However, its impact in thyroid hormone synthesis and secretion is poorly studied. The aim of this investigation was to evaluate the dynamics of thyroid hormones and pituitary thyroid-stimulating hormone secretion during bilateral shifts in deuterium supply and assess a possible role of the Na+/I- symporter (NIS), the main iodide transporter, in altered thyroid function. The experiment was performed on adult male Wistar rats, which consumed deuterium-depleted ([D] = 10 ppm) and deuterium-enriched ([D] = 500,000 ppm) water for 21 days. The assessment of total thyroxine and triiodothyronine and their free fractions, as well as thyroid-stimulating hormone in blood serum, revealed the rapid response of the thyroid gland to shifts in the deuterium/protium balance. The present investigation shows that the bilateral changes in the deuterium body content similarly modulate thyroid hormone production and functional activity of the pituitary gland, but the responses of the thyroid and pituitary glands differ. The response of the thyroid cells was to increase the synthesis of the hormones and the pituitary thyrotropes, in order to reduce the production of the thyroid-stimulating hormone. The evaluation of NIS serum levels found a gradual increase in the rats that consumed deuterium-enriched water and no differences in the group exposed to deuterium depletion. NIS levels in both groups did not correlate with thyroid hormones and pituitary thyroid-stimulating hormone production. The data obtained show that thyroid gland has a higher sensitivity to shifts in the deuterium body content than the hypothalamic-pituitary complex, which responded later but similarly in the case of deuteration or deuterium depletion. It indicates a different sensitivity of the endocrine glands to alterations in deuterium content. It suggests that thyroid hormone production rate may depend on deuterium blood/tissue and cytosol/organelle gradients, which possibly disturb the secretory process independently of the NIS.


Asunto(s)
Simportadores , Glándula Tiroides , Masculino , Ratas , Animales , Deuterio , Ratas Wistar , Tiroxina/farmacología , Hormonas Tiroideas , Triyodotironina/farmacología , Tirotropina , Hipófisis
3.
Int J Mol Sci ; 24(3)2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36769098

RESUMEN

Dichlorodiphenyltrichloroethane (DDT) is the most widespread persistent pollutant with endocrine-disrupting properties. DDT has been shown to disrupt secretory and morphogenetic processes in the adrenal cortex. The present investigation aimed to evaluate transcriptional regulation of postnatal growth of the adrenal medulla and formation of the pools necessary for self-renewal of medullary cells in rats that developed under low-dose exposure to DDT. The study was performed using male Wistar rats exposed to low doses of o,p'-DDT during prenatal and postnatal development. Light microscopy and histomorphometry revealed diminished medulla growth in the DDT-exposed rats. Evaluation of Ki-67 expression in chromaffin cells found later activation of proliferation indicative of retarded growth of the adrenal medulla. All DDT-exposed rats exhibited a gradual decrease in tyrosine hydroxylase production by adrenal chromaffin cells. Immunohistochemical evaluation of nuclear ß-catenin, transcription factor Oct4, and ligand of sonic hedgehog revealed increased expression of all factors after termination of growth in the control rats. The DDT-exposed rats demonstrated diminished increases in Oct4 and sonic hedgehog expression and lower levels of canonical Wnt signaling activation. Thus, developmental exposure to the endocrine disruptor o,p'-DDT alters the transcriptional regulation of morphogenetic processes in the adrenal medulla and evokes a slowdown in its growth and in the formation of a reserve pool of cells capable of dedifferentiation and proliferation that maintain cellular homeostasis in adult adrenals.


Asunto(s)
Médula Suprarrenal , DDT , Embarazo , Femenino , Ratas , Animales , Masculino , DDT/toxicidad , Ratas Wistar , Proteínas Hedgehog/genética
4.
Int J Mol Sci ; 23(9)2022 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-35563302

RESUMEN

Epinephrine is the most abundant catecholamine hormone, produced by the nervous system and adrenal glands. Endocrine disruption of epinephrine synthesis, secretion and signaling is less studied than steroid and thyroid hormones. Dichlorodiphenyltrichloroethane (DDT) is recognized as one of the most prominent environmental contaminants with a long half-life. It is a potent endocrine disrupter affecting sex steroid, mineralocorticoid, glucocorticoid and thyroid hormone production. Exposure to low doses of DDT is universal and begins in utero. Therefore, we studied adrenal medulla growth and function in male Wistar rats exposed to low doses of DDT during prenatal and postnatal development until puberty and adulthood, as well as rats exposed to DDT since the first day of postnatal development. All the exposed rats demonstrated lowered epinephrine blood levels, gradually reducing with age. DDT was found to inhibit the synthesis of tyrosine hydroxylase and affect the mitochondrial apparatus of epinephrine-producing cells during puberty and even after maturation. Low-dose exposure to DDT from birth resulted in more pronounced changes in adrenomedullary cells and a more profound decrease (up to 50%) in epinephrine secretion in adult rats. Prenatal onset of exposure demonstrated a mild effect on epinephrine-producing function (30% reduction), but was associated with lower rate of adrenal medulla growth during maturation and 25% smaller adrenal medullar size in adult rats. All subjects exposed to low doses of DDT failed to develop adaptive changes and restore proper epinephrine production. These results indicate a dysmorphogenetic effect of prenatal exposure and disruption of secretory function of adrenal chromaffin cells by postnatal exposure to DDT.


Asunto(s)
Médula Suprarrenal , Disruptores Endocrinos , Efectos Tardíos de la Exposición Prenatal , Adulto , Animales , DDT/toxicidad , Disruptores Endocrinos/toxicidad , Epinefrina , Femenino , Humanos , Masculino , Embarazo , Ratas , Ratas Wistar
5.
Int J Mol Sci ; 23(12)2022 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-35743120

RESUMEN

The impact of endocrine-disrupting chemicals on the development and involution of the immune system is a possible reason for the increased incidence of disorders associated with inappropriate immune function. The thymus is a lymphoid and also an endocrine organ, and, accordingly, its development and functioning may be impaired by endocrine disruptors. The aim was to evaluate age-related thymus involution in mature rats exposed to the endocrine disruptor DDT during prenatal and postnatal ontogeny. Methodology included in vivo experiment on male Wistar rats exposed to low doses of DDT during prenatal and postnatal development and morphological assessment of thymic involution, including the immunohistochemical detection of proliferating thymocytes. The study was carried out at the early stage of involution. Results: DDT-exposed rats exhibited a normal anatomy, and the relative weight of the thymus was within the control ranges. Histological and immunohistochemical examinations revealed increased cellularity of the cortex and the medulla, higher content of lymphoblasts, and more intensive proliferation rate of thymocytes compared to the control. Evaluation of thymic epithelial cells revealed a higher rate of thymic corpuscles formation. Conclusion: The data obtained indicate that endocrine disrupter DDT disturbs postnatal development of the thymus. Low-dose exposure to DDT during ontogeny does not suppress growth rate but violates the developmental program of the thymus by slowing down the onset of age-related involution and maintaining high cell proliferation rate. It may result in excessive formation of thymus-dependent areas in peripheral lymphoid organs and altered immune response.


Asunto(s)
DDT , Disruptores Endocrinos , Animales , DDT/toxicidad , Disruptores Endocrinos/toxicidad , Femenino , Masculino , Embarazo , Ratas , Ratas Wistar , Timocitos , Timo
6.
J Biol Chem ; 295(33): 11720-11728, 2020 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-32580946

RESUMEN

Post-translational modifications of proteins involved in calcium handling in myocytes, such as the cardiac ryanodine receptor (RyR2), critically regulate cardiac contractility. Recent studies have suggested that phosphorylation of RyR2 by protein kinase G (PKG) might contribute to the cardioprotective effects of cholinergic stimulation. However, the specific mechanisms underlying these effects remain unclear. Here, using murine ventricular myocytes, immunoblotting, proximity ligation as-says, and nitric oxide imaging, we report that phosphorylation of Ser-2808 in RyR2 induced by the muscarinic receptor agonist carbachol is mediated by a signaling axis comprising phosphoinositide 3-phosphate kinase, Akt Ser/Thr kinase, nitric oxide synthase 1, nitric oxide, soluble guanylate cyclase, cyclic GMP (cGMP), and PKG. We found that this signaling pathway is compartmentalized in myocytes, as it was distinct from atrial natriuretic peptide receptor-cGMP-PKG-RyR2 Ser-2808 signaling and independent of muscarinic-induced phosphorylation of Ser-239 in vasodilator-stimulated phosphoprotein. These results provide detailed insights into muscarinic-induced PKG signaling and the mediators that regulate cardiac RyR2 phosphorylation critical for cardiovascular function.


Asunto(s)
Proteínas Quinasas Dependientes de GMP Cíclico/metabolismo , Óxido Nítrico Sintasa de Tipo I/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Canal Liberador de Calcio Receptor de Rianodina/metabolismo , Transducción de Señal , Animales , Células Cultivadas , Ratones Endogámicos C57BL , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Fosforilación
7.
Int J Mol Sci ; 22(6)2021 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-33808818

RESUMEN

Dichlorodiphenyltrichloroethane (DDT) is the most widespread, persistent pollutant and endocrine disruptor on the planet. Although DDT has been found to block androgen receptors, the effects of its low-dose exposure in different periods of ontogeny on the male reproductive system remain unclear. We evaluate sex steroid hormone production in the pubertal period and after maturation in male Wistar rats exposed to low doses of o,p'-DDT, either during prenatal and postnatal development or postnatal development alone. Prenatally and postnatally exposed rats exhibit lower testosterone production and increased estradiol and estriol serum levels after maturation, associated with the delayed growth of gonads. Postnatally exposed rats demonstrate accelerated growth of gonads and higher testosterone production in the pubertal period. In contrast to the previous group, they do not present raised estradiol production. All of the exposed animals exhibit a reduced conversion of progesterone to 17OH-progesterone after sexual maturation, which indicates putative attenuation of sex steroid production. Thus, the study reveals age-dependent outcomes of low-dose exposure to DDT. Prenatal onset of exposure results in the later onset of androgen production and the enhanced conversion of androgens to estrogens after puberty, while postnatal exposure induces the earlier onset of androgen secretion.


Asunto(s)
Andrógenos/biosíntesis , DDT/farmacología , Disruptores Endocrinos/farmacología , Exposición a Riesgos Ambientales/efectos adversos , Estrógenos/biosíntesis , Animales , DDT/administración & dosificación , Disruptores Endocrinos/administración & dosificación , Femenino , Genitales Masculinos/efectos de los fármacos , Genitales Masculinos/metabolismo , Hormonas Esteroides Gonadales/biosíntesis , Gónadas/efectos de los fármacos , Gónadas/metabolismo , Masculino , Ratas
8.
Int J Mol Sci ; 22(12)2021 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-34204839

RESUMEN

Dichlorodiphenyltrichloroethane (DDT) is a persistent organic pollutant and one of the most widespread endocrine disrupting chemicals. The impact of low-dose exposure to DDT on the morphogenesis of the adrenal gland is still poorly understood. The development and function of zona glomerulosa in rats has been found to be associated with changes in the expression of the transcription factor Oct4 (Octamer 4), which is the most important player in cell pluripotency. The aim of the study was to investigate the morphogenesis and function of rat adrenal zona glomerulosa in rats exposed to low doses of DDT during prenatal and postnatal development and to determine the possible role of Oct4 in DDT-mediated structural and functional changes. The DDT-exposed rats demonstrated slower development and lower functional activity of the zona glomerulosa during the pubertal period associated with higher expression of Oct4. Further, accelerated growth and restoration of hormone production was associated with, firstly, a decrease in Oct4 expressing cells and secondly, the loss of the inverse relationship between basal aldosterone levels and the number of Oct4 expressing cells. Thus, the transcriptional factor Oct4 exhibited an altered pattern of expression in the DDT-exposed rats during postnatal development. The results of the study uncover a novel putative mechanism by which low doses of DDT disrupt the development of adrenal zona glomerulosa.


Asunto(s)
DDT/toxicidad , Morfogénesis , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , Zona Glomerular/patología , Aldosterona/biosíntesis , Aldosterona/sangre , Animales , Proliferación Celular/efectos de los fármacos , Femenino , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/sangre , Ratas Wistar
9.
Nature ; 510(7504): 293-297, 2014 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-24805245

RESUMEN

Efficient duplication of the genome requires the concerted action of helicase and DNA polymerases at replication forks to avoid stalling of the replication machinery and consequent genomic instability. In eukaryotes, the physical coupling between helicase and DNA polymerases remains poorly understood. Here we define the molecular mechanism by which the yeast Ctf4 protein links the Cdc45-MCM-GINS (CMG) DNA helicase to DNA polymerase α (Pol α) within the replisome. We use X-ray crystallography and electron microscopy to show that Ctf4 self-associates in a constitutive disk-shaped trimer. Trimerization depends on a ß-propeller domain in the carboxy-terminal half of the protein, which is fused to a helical extension that protrudes from one face of the trimeric disk. Critically, Pol α and the CMG helicase share a common mechanism of interaction with Ctf4. We show that the amino-terminal tails of the catalytic subunit of Pol α and the Sld5 subunit of GINS contain a conserved Ctf4-binding motif that docks onto the exposed helical extension of a Ctf4 protomer within the trimer. Accordingly, we demonstrate that one Ctf4 trimer can support binding of up to three partner proteins, including the simultaneous association with both Pol α and GINS. Our findings indicate that Ctf4 can couple two molecules of Pol α to one CMG helicase within the replisome, providing a new model for lagging-strand synthesis in eukaryotes that resembles the emerging model for the simpler replisome of Escherichia coli. The ability of Ctf4 to act as a platform for multivalent interactions illustrates a mechanism for the concurrent recruitment of factors that act together at the fork.


Asunto(s)
ADN Helicasas/metabolismo , ADN Polimerasa I/metabolismo , Replicación del ADN , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , ADN Polimerasa Dirigida por ADN/química , ADN Polimerasa Dirigida por ADN/metabolismo , Complejos Multienzimáticos/química , Complejos Multienzimáticos/metabolismo , Multimerización de Proteína , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/química , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Dominio Catalítico , Secuencia Conservada , Cristalografía por Rayos X , ADN Helicasas/química , ADN Helicasas/ultraestructura , ADN Polimerasa I/química , ADN Polimerasa I/ultraestructura , Proteínas de Unión al ADN/ultraestructura , Microscopía Electrónica , Proteínas de Mantenimiento de Minicromosoma/química , Proteínas de Mantenimiento de Minicromosoma/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Unión Proteica , Estructura Cuaternaria de Proteína , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Saccharomyces cerevisiae/ultraestructura , Proteínas de Saccharomyces cerevisiae/ultraestructura
10.
Cardiovasc Drugs Ther ; 33(3): 339-352, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31011880

RESUMEN

BACKGROUND: Clinical guidelines recommend peri-cardioversion anticoagulation in patients with atrial fibrillation (AF). We performed a systematic review and meta-analysis to compare the safety and efficacy of direct oral anticoagulants (DOACs) versus vitamin K antagonists (VKAs) in patients with AF undergoing cardioversion. METHODS: We searched CENTRAL, MEDLINE, and EMBASE for randomized controlled trials (RCTs) and observational studies comparing DOACs to VKAs in patients undergoing cardioversion for AF. We performed title, abstract, and full-text screening, data extraction, and risk of bias evaluation independently and in duplicate. We pooled data using a random effects model and evaluated the overall quality of evidence using Grading of Recommendations Assessment, Development and Evaluation. RESULTS: We identified three eligible RCTs (n = 5203) and 21 observational studies (n = 11,855). The three RCTs and four observational studies were at low risk of bias. In RCTs (mean follow-up, 30 days), thromboembolic events occurred in 0.18% of patients receiving DOACs, as compared with 0.55% receiving VKAs (relative risk [RR] 0.40, 95% CI [0.13, 1.24], moderate quality). Major bleeding occurred in 0.42% of patients receiving DOACs as compared with 0.64% receiving VKAs (RR 0.62, 95% CI [0.28, 1.35], moderate quality), and death occurred in 0.28% of patients receiving DOACs as compared with 0.38% receiving VKAs (RR 0.70, 95% CI [0.23, 2.10], low quality). Confidence in the estimates of effect for observational studies was very low. CONCLUSION: DOACs peri-cardioversion in patients with AF appears safe from both a bleeding and thromboembolic risk perspective. Available evidence supports the use of DOACs as standard of care peri-cardioversion in patients with AF.


Asunto(s)
Anticoagulantes/administración & dosificación , Antitrombinas/administración & dosificación , Fibrilación Atrial/terapia , Cardioversión Eléctrica , Accidente Cerebrovascular/prevención & control , Vitamina K/antagonistas & inhibidores , Warfarina/administración & dosificación , Administración Oral , Anticoagulantes/efectos adversos , Antitrombinas/efectos adversos , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/mortalidad , Cardioversión Eléctrica/efectos adversos , Hemorragia/inducido químicamente , Humanos , Estudios Observacionales como Asunto , Ensayos Clínicos Controlados Aleatorios como Asunto , Medición de Riesgo , Factores de Riesgo , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/mortalidad , Resultado del Tratamiento , Warfarina/efectos adversos
11.
Proc Natl Acad Sci U S A ; 111(16): 5980-5, 2014 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-24711416

RESUMEN

Adaptive immunity in humans is provided by hypervariable Ig-like molecules on the surface of B and T cells. The final set of these molecules in each organism is formed under the influence of two forces: individual genetic traits and the environment, which includes the diverse spectra of alien and self-antigens. Here we assess the impact of individual genetic factors on the formation of the adaptive immunity by analyzing the T-cell receptor (TCR) repertoires of three pairs of monozygous twins by next-generation sequencing. Surprisingly, we found that an overlap between the TCR repertoires of monozygous twins is similar to an overlap between the TCR repertoires of nonrelated individuals. However, the number of identical complementary determining region 3 sequences in two individuals is significantly increased for twin pairs in the fraction of highly abundant TCR molecules, which is enriched by the antigen-experienced T cells. We found that the initial recruitment of particular TCR V genes for recombination and subsequent selection in the thymus is strictly determined by individual genetic factors. J genes of TCRs are selected randomly for recombination; however, the subsequent selection in the thymus gives preference to some α but not ß J segments. These findings provide a deeper insight into the mechanism of TCR repertoire generation.


Asunto(s)
Secuenciación de Nucleótidos de Alto Rendimiento , Receptores de Antígenos de Linfocitos T/genética , Gemelos Monocigóticos/genética , Células Clonales , Regiones Determinantes de Complementariedad/genética , Femenino , Biblioteca de Genes , Variación Genética , Humanos , Análisis de Secuencia de ADN , Linfocitos T/metabolismo , Timo/metabolismo
12.
Acta Crystallogr D Biol Crystallogr ; 71(Pt 3): 555-64, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25760605

RESUMEN

Many components of epithelial polarity protein complexes possess PDZ domains that are required for protein interaction and recruitment to the apical plasma membrane. Apical localization of the Crumbs (Crb) transmembrane protein requires a PDZ-mediated interaction with Pals1 (protein-associated with Lin7, Stardust, MPP5), a member of the p55 family of membrane-associated guanylate kinases (MAGUKs). This study describes the molecular interaction between the Crb carboxy-terminal motif (ERLI), which is required for Drosophila cell polarity, and the Pals1 PDZ domain using crystallography and fluorescence polarization. Only the last four Crb residues contribute to Pals1 PDZ-domain binding affinity, with specificity contributed by conserved charged interactions. Comparison of the Crb-bound Pals1 PDZ structure with an apo Pals1 structure reveals a key Phe side chain that gates access to the PDZ peptide-binding groove. Removal of this side chain enhances the binding affinity by more than fivefold, suggesting that access of Crb to Pals1 may be regulated by intradomain contacts or by protein-protein interaction.


Asunto(s)
Proteínas del Ojo , Proteínas de la Membrana , Proteínas del Tejido Nervioso , Nucleósido-Fosfato Quinasa , Secuencias de Aminoácidos , Animales , Proteínas de Drosophila/química , Proteínas de Drosophila/genética , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Proteínas del Ojo/química , Proteínas del Ojo/genética , Proteínas del Ojo/metabolismo , Guanilato-Quinasas/química , Guanilato-Quinasas/genética , Guanilato-Quinasas/metabolismo , Humanos , Proteínas de la Membrana/química , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Proteínas de Transporte de Membrana/química , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/genética , Proteínas del Tejido Nervioso/metabolismo , Nucleósido-Fosfato Quinasa/química , Nucleósido-Fosfato Quinasa/genética , Nucleósido-Fosfato Quinasa/metabolismo , Unión Proteica , Estructura Cuaternaria de Proteína , Estructura Terciaria de Proteína
13.
Avian Dis ; 59(1): 31-7, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26292531

RESUMEN

Unformulated oligodeoxynucleotides (ODN) containing CpG motifs (CpG-ODN) have been shown to stimulate the innate immune system against a variety of bacterial, viral, and protozoan infections in a variety of vertebrate species. We have previously shown that in ovo delivery of unformulated CpG-ODN was able to significantly protect neonatal broiler chickens against Escherichia coli or Salmonella Typhimurium infections. The objectives of this study were to examine the safety and immunoprotective effects of CpG-ODN formulated with 2 types of carbon nanotubes (CNTs) or 2 types of lipid-surfactant (LSC) delivery systems in neonatal broilers against E. coli septicemia. Embryonated eggs, which had been incubated for 18 days, received either 50 µg of CNT-CpG-ODN, 50 µg of LSC-CpG-ODN, 50 µg of unformulated CpG-ODN, or saline. Four days after exposure to CpG-ODN (day 1 posthatch), 1 x 10(4) or 1 x 10(5) colony-forming units of a virulent strain of E. coli isolated from a turkey with septicemia were inoculated subcutaneously in the neck. Clinical signs, pathology, bacterial isolations from the air sacs, and mortality were observed for 8 days following challenge with E. coli. Bacterial isolations and pathologic observations were conducted immediately after birds were dead or euthanatized. The survival rate of birds in groups receiving saline following E. coli infection was 20% to 30%. In contrast, birds receiving CpG-ODN formulations had a significantly higher survival rate of 60% to 80% (P < 0.01). Bacterial loads and clinical scores were significantly lower (P < 0.05) in groups treated with CNT- or LSC-CpG-ODN compared to the groups receiving CpG-ODN or saline. Moreover, there is no evidence of any adverse effects of these formulations in any organs or in growth rates of birds until 42 days of age. This is the first time that CpG-ODN formulated with CNT and LSC have been demonstrated to have an immunomodulatory effect against an E. coli infection in neonatal broiler chickens following in ovo delivery.


Asunto(s)
Pollos , Infecciones por Escherichia coli/veterinaria , Liposomas , Nanotubos de Carbono , Oligodesoxirribonucleótidos/farmacología , Óvulo , Animales , Infecciones por Escherichia coli/prevención & control , Oligodesoxirribonucleótidos/administración & dosificación , Enfermedades de las Aves de Corral/prevención & control
14.
Nanomedicine ; 10(8): 1637-47, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24905400

RESUMEN

Gene therapy could offer improvement in the treatment of glaucoma compared to the current standard of lowering intraocular pressure. We have developed and characterized non-viral gemini surfactant-phospholipid nanoparticles (GL-NPs) for intravitreal and topical administration. Optimized GL-NPs (size range 150-180 nm) were biocompatible with rat retinal ganglion (RGC-5) cells with >95% viability by PrestoBlue™ assay. GL-NPs carrying Cy5-labeled plasmid DNA demonstrated distinct trafficking behavior and biodisposition within the eye in vivo after intravitreal or topical application with respect to pathways of movement and physicochemical stability. After intravitreal injection in mice, GL-NPs localized within the nerve fiber layer of the retina, whereas after topical application, GL-NPs were located in several anterior chamber tissues, including the limbus, iris and conjunctiva. GL-NPs were thermodynamically stable in the vitreous and tear fluid and were trafficked as single, non-aggregated particles after both types of administration. FROM THE CLINICAL EDITOR: In this paper, the development and characterization of non-viral gemini surfactant-phospholipid nanoparticles is reported with the goal of establishing a gene delivery system that addresses glaucoma in a non-invasive fashion. The authors found that after topical application, the concentration of these nanoparticles was higher in anterior chamber-related components of the eye, whereas intra-vitreal administration resulted in accumulation in the retinal nerve fibre layer.


Asunto(s)
Ojo/metabolismo , Terapia Genética/métodos , Glaucoma/terapia , Nanopartículas/química , Administración Tópica , Animales , Técnicas de Transferencia de Gen , Masculino , Ratones , Ratones Endogámicos C57BL
15.
Behav Sci (Basel) ; 14(2)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38392477

RESUMEN

A central question in behavioural neuroscience is how different rewards modulate learning. While the role of monetary rewards is well-studied in decision-making research, the influence of abstract rewards like music remains poorly understood. This study investigated the dissociable effects of these two reward types on decision making. Forty participants completed two decision-making tasks, each characterised by probabilistic associations between stimuli and rewards, with probabilities changing over time to reflect environmental volatility. In each task, choices were reinforced either by monetary outcomes (win/lose) or by the endings of musical melodies (consonant/dissonant). We applied the Hierarchical Gaussian Filter, a validated hierarchical Bayesian framework, to model learning under these two conditions. Bayesian statistics provided evidence for similar learning patterns across both reward types, suggesting individuals' similar adaptability. However, within the musical task, individual preferences for consonance over dissonance explained some aspects of learning. Specifically, correlation analyses indicated that participants more tolerant of dissonance behaved more stochastically in their belief-to-response mappings and were less likely to choose the response associated with the current prediction for a consonant ending, driven by higher volatility estimates. By contrast, participants averse to dissonance showed increased tonic volatility, leading to larger updates in reward tendency beliefs.

16.
Biomedicines ; 12(5)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38790918

RESUMEN

The thymus provides maturation and migration of T cells to peripheral organs of immunity, where they recognize diverse antigens and maintain immunological memory and self-tolerance. The thymus is known to be involved with age and in response to stress factors. Therefore, the search for approaches to the restoration of thymopoiesis is of great interest. The present investigation was aimed at evaluating how prolonged deuterium depletion affects morphogenetic processes and the physiological transition of the thymus to age-related involution. The study was performed on 60 male Wistar rats subjected to consumption of deuterium-depleted water with a 10 ppm deuterium content for 28 days. The control rats consumed distilled water with a normal deuterium content of 150 ppm. The examination found no significant differences in body weight gain or the amount of water consumed. The exposed rats exhibited similar to control dynamics of the thymus weight but significant changes in thymic cell maturation according to cytofluorimetric analysis of thymic subpopulations. Changes in T cell production were not monotonic and differentially engaged morphogenetic processes of cell proliferation, differentiation, and migration. The reactive response to deuterium depletion was a sharp increase in the number of progenitor CD4-CD8- cells and their differentiation into T cells. The compensatory reaction was inhibition of thymopoiesis with more pronounced suppression of differentiation of T-cytotoxic lymphocytes, followed by intensification of emigration of mature T cells to the bloodstream. This period lasts from 3 to 14 days, then differentiation of thymic lymphocytes is restored, later cell proliferation is activated, and finally the thymopoiesis rate exceeds the control values. The increase in the number of thymic progenitor cells after 3-4 weeks suggests consideration of deuterium elimination as a novel approach to prevent thymus involution.

17.
J Bone Jt Infect ; 9(1): 87-97, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38601005

RESUMEN

Introduction: The BIOFIRE Joint Infection (JI) Panel is a diagnostic tool that uses multiplex-PCR testing to detect microorganisms in synovial fluid specimens from patients suspected of having septic arthritis (SA) on native joints or prosthetic joint infections (PJIs). Methods: A study was conducted across 34 clinical sites in 19 European and Middle Eastern countries from March 2021 to June 2022 to assess the effectiveness of the BIOFIRE JI Panel. Results: A total of 1527 samples were collected from patients suspected of SA or PJI, with an overall agreement of 88.4 % and 85 % respectively between the JI Panel and synovial fluid cultures (SFCs). The JI Panel detected more positive samples and microorganisms than SFC, with a notable difference on Staphylococcus aureus, Streptococcus species, Enterococcus faecalis, Kingella kingae, Neisseria gonorrhoeae, and anaerobic bacteria. The study found that the BIOFIRE JI Panel has a high utility in the real-world clinical setting for suspected SA and PJI, providing diagnostic results in approximately 1 h. The user experience was positive, implying a potential benefit of rapidity of results' turnover in optimising patient management strategies. Conclusion: The study suggests that the BIOFIRE JI Panel could potentially optimise patient management and antimicrobial therapy, thus highlighting its importance in the clinical setting.

18.
Mol Pharm ; 10(6): 2248-60, 2013 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-23587061

RESUMEN

The outermost layer of the skin, known as the stratum corneum (SC), is composed of dead corneocytes embedded in an intercellular lipid matrix consisting of ceramides, free fatty acids, and cholesterol. The high level of organization within this matrix protects the body by limiting the permeation of most compounds through the skin. While essential for its protective functions, the SC poses a significant barrier for the delivery of topically applied pharmaceutical agents. Chemical permeation enhancers (CPEs) can increase delivery of small drug compounds into the skin by interacting with the intercellular lipids through physical processes including extraction, fluidization, increased disorder, and phase separation. However, it is not clear whether these same mechanisms are involved in delivery of biotherapeutic macromolecules, such as proteins. Here we describe the effect of three categories of CPEs {solvents [ethanol, propylene glycol, diethylene glycol monoethyl ether (transcutol), oleic acid], terpenes [menthol, nerol, camphor, methyl salicylate], and surfactants [Tween 80, SDS, benzalkonium chloride, polyoxyl 40 hydrogenated castor oil (Cremophor RH40), didecyldimethylammonium bromide (DDAB), didecyltrimethylammonium bromide (DTAB)]} on the lipid organizational structure of human SC as determined by X-ray scattering studies. Small- and wide-angle X-ray scattering studies were conducted to correlate the degree of structural changes and hydrocarbon chain packing in SC lipids caused by these various classes of CPEs to the extent of permeation of interferon alpha-2b (IFNα), a 19 kDa protein drug, into human skin. With the exception of solvents, propylene glycol and ethanol, all classes of CPEs caused increased disordering of lamellar and lateral packing of lipids. We observed that the highest degree of SC lipid disordering was caused by surfactants (especially SDS, DDAB, and DTAB) followed by terpenes, such as nerol. Interestingly, in vitro skin permeation studies indicated that, in most cases, absorption of IFNα was low and that an increase in SC lipid disorder does not correspond to an increase in IFNα absorption.


Asunto(s)
Interferón-alfa/metabolismo , Mama/metabolismo , Femenino , Humanos , Técnicas In Vitro , Microscopía Confocal , Absorción Cutánea/fisiología
19.
Front Psychol ; 14: 1193822, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37425183

RESUMEN

Word stress is demanding for non-native learners of English, partly because speakers from different backgrounds weight perceptual cues to stress like pitch, intensity, and duration differently. Slavic learners of English and particularly those with a fixed stress language background like Czech and Polish have been shown to be less sensitive to stress in their native and non-native languages. In contrast, German English learners are rarely discussed in a word stress context. A comparison of these varieties can reveal differences in the foreign language processing of speakers from two language families. We use electroencephalography (EEG) to explore group differences in word stress cue perception between Slavic and German learners of English. Slavic and German advanced English speakers were examined in passive multi-feature oddball experiments, where they were exposed to the word impact as an unstressed standard and as deviants stressed on the first or second syllable through higher pitch, intensity, or duration. The results revealed a robust Mismatch Negativity (MMN) component of the event-related potential (ERP) in both language groups in response to all conditions, demonstrating sensitivity to stress changes in a non-native language. While both groups showed higher MMN responses to stress changes to the second than the first syllable, this effect was more pronounced for German than for Slavic participants. Such group differences in non-native English word stress perception from the current and previous studies are argued to speak in favor of customizable language technologies and diversified English curricula compensating for non-native perceptual variation.

20.
Commun Biol ; 6(1): 271, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36922553

RESUMEN

Anxiety has been linked to altered belief formation and uncertainty estimation, impacting learning. Identifying the neural processes underlying these changes is important for understanding brain pathology. Here, we show that oscillatory activity in the medial prefrontal, anterior cingulate and orbitofrontal cortex (mPFC, ACC, OFC) explains anxiety-related learning alterations. In a magnetoencephalography experiment, two groups of human participants pre-screened with high and low trait anxiety (HTA, LTA: 39) performed a probabilistic reward-based learning task. HTA undermined learning through an overestimation of volatility, leading to faster belief updating, more stochastic decisions and pronounced lose-shift tendencies. On a neural level, we observed increased gamma activity in the ACC, dmPFC, and OFC during encoding of precision-weighted prediction errors in HTA, accompanied by suppressed ACC alpha/beta activity. Our findings support the association between altered learning and belief updating in anxiety and changes in gamma and alpha/beta activity in the ACC, dmPFC, and OFC.


Asunto(s)
Giro del Cíngulo , Aprendizaje , Humanos , Corteza Prefrontal , Recompensa , Ansiedad
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