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1.
Proc Natl Acad Sci U S A ; 120(1): e2210561119, 2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36584294

RESUMEN

Brown algae annually convert gigatons of carbon dioxide into carbohydrates, including the complex extracellular matrix polysaccharide fucoidan. Due to its persistence in the environment, fucoidan is potentially a pathway for marine carbon sequestration. Rates of fucoidan secretion by brown algae remain unknown due to the challenge of identifying and quantifying complex polysaccharides in seawater. We adapted the techniques of anion exchange chromatography, enzyme-linked immunosorbent assay, and biocatalytic enzyme-based assay for detection and quantification of fucoidan. We found the brown alga Fucus vesiculosus at the Baltic Sea coast of south-west Finland to secrete 0.3% of their biomass as fucoidan per day. Dissolved fucoidan concentrations in seawater adjacent to algae reached up to 0.48 mg L-1. Fucoidan accumulated during incubations of F. vesiculosus, significantly more in light than in darkness. Maximum estimation by acid hydrolysis indicated fucoidan secretion at a rate of 28 to 40 mg C kg-1 h-1, accounting for 44 to 50% of all exuded dissolved organic carbon. Composed only of carbon, oxygen, hydrogen, and sulfur, fucoidan secretion does not consume nutrients enabling carbon sequestration independent of algal growth. Extrapolated over a year, the algae sequester more carbon into secreted fucoidan than their biomass. The global utility of fucoidan secretion is an alternative pathway for carbon dioxide removal by brown algae without the need to harvest or bury algal biomass.


Asunto(s)
Dióxido de Carbono , Phaeophyceae , Dióxido de Carbono/metabolismo , Polisacáridos/metabolismo , Phaeophyceae/metabolismo , Océanos y Mares
2.
Brain ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39028640

RESUMEN

Huntington's disease and juvenile-onset schizophrenia have long been regarded as distinct disorders. However, both manifest cell-intrinsic abnormalities in glial differentiation, with resultant astrocytic dysfunction and hypomyelination. To assess whether a common mechanism might underlie the similar glial pathology of these otherwise disparate conditions, we used comparative correlation network approaches to analyse RNA-sequencing data from human glial progenitor cells (hGPCs) produced from disease-derived pluripotent stem cells. We identified gene sets preserved between Huntington's disease and schizophrenia hGPCs yet distinct from normal controls that included 174 highly connected genes in the shared disease-associated network, focusing on genes involved in synaptic signalling. These synaptic genes were largely suppressed in both schizophrenia and Huntington's disease hGPCs, and gene regulatory network analysis identified a core set of upstream regulators of this network, of which OLIG2 and TCF7L2 were prominent. Among their downstream targets, ADGRL3, a modulator of glutamatergic synapses, was notably suppressed in both schizophrenia and Huntington's disease hGPCs. Chromatin immunoprecipitation sequencing confirmed that OLIG2 and TCF7L2 each bound to the regulatory region of ADGRL3, whose expression was then rescued by lentiviral overexpression of these transcription factors. These data suggest that the disease-associated suppression of OLIG2 and TCF7L2-dependent transcription of glutamate signalling regulators may impair glial receptivity to neuronal glutamate. The consequent loss of activity-dependent mobilization of hGPCs may yield deficient oligodendrocyte production, and hence the hypomyelination noted in these disorders, as well as the disrupted astrocytic differentiation and attendant synaptic dysfunction associated with each. Together, these data highlight the importance of convergent glial molecular pathology in both the pathogenesis and phenotypic similarities of two otherwise unrelated disorders, Huntington's disease and schizophrenia.

3.
Emerg Infect Dis ; 30(3): 499-509, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38407176

RESUMEN

We characterized the spatial distribution of drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB) cases in Ho Chi Minh City, Vietnam, a major metropolis in southeastern Asia, and explored demographic and socioeconomic factors associated with local TB burden. Hot spots of DS and MDR TB incidence were observed in the central parts of Ho Chi Minh City, and substantial heterogeneity was observed across wards. Positive spatial autocorrelation was observed for both DS TB and MDR TB. Ward-level TB incidence was associated with HIV prevalence and the male proportion of the population. No ward-level demographic and socioeconomic indicators were associated with MDR TB case count relative to total TB case count. Our findings might inform spatially targeted TB control strategies and provide insights for generating hypotheses about the nature of the relationship between DS and MDR TB in Ho Chi Minh City and the wider southeastern region of Asia.


Asunto(s)
Tuberculosis Resistente a Múltiples Medicamentos , Tuberculosis , Masculino , Humanos , Vietnam/epidemiología , Tuberculosis Resistente a Múltiples Medicamentos/epidemiología , Asia , Análisis Espacial
4.
Phys Rev Lett ; 132(15): 155101, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38682996

RESUMEN

The sheared-flow-stabilized Z pinch concept has been studied extensively and is able to produce fusion-relevant plasma parameters along with neutron production over several microseconds. We present here elevated electron temperature results spatially and temporally coincident with the plasma neutron source. An optical Thomson scattering apparatus designed for the FuZE device measures temperatures in the range of 1-3 keV on the axis of the device, 20 cm downstream of the nose cone. The 17-fiber system measures the radial profiles of the electron temperature. Scanning the laser time with respect to the neutron pulse time over a series of discharges allows the reconstruction of the T_{e} temporal response, confirming that the electron temperature peaks simultaneously with the neutron output, as well as the pinch current and inductive voltage generated within the plasma. Comparison to spectroscopic ion temperature measurements suggests a plasma in thermal equilibrium. The elevated T_{e} confirms the presence of a plasma assembled on axis, and indicates limited radiative losses, demonstrating a basis for scaling this device toward net gain fusion conditions.

5.
Phys Chem Chem Phys ; 25(12): 8779-8788, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36912122

RESUMEN

Novel Janus materials have attracted broad interest due to the outstanding properties created by their out-of-plane asymmetry, with increasing theoretical exploration and more reports of successful fabrication in recent years. Here, we construct and explore the crystal structures, stabilities, electronic band structures, and transport properties - including carrier mobilities - of two-dimensional Janus MGeSiP4 (M = Ti, Zr, or Hf) monolayers based on density functional theory calculations. From the cohesive energies, elastic constants, and phonon dispersion calculations, the monolayers are confirmed to exhibit structural stability with high feasibility for experimental synthesis. All the structures are indirect band-gap semiconductors with calculated band-gap energies in the range of 0.77 eV to 1.01 eV at the HSE06 (Heyd-Scuseria-Ernzerhof) level. Interestingly, by applying external biaxial strain, a semiconductor to metal phase transition is observed for the three Janus structures. This suggests potential for promising applications in optoelectronic and electromechanical devices. Notably, the MGeSiP4 monolayers show directionally anisotropic carrier mobility with a high electron mobility of up to 2.72 × 103 cm2 V-1 s-1 for the ZrGeSiP4 monolayer, indicating advantages for applications in electronic devices. Hence, the presented results reveal the novel properties of the 2D Janus MGeSiP4 monolayers and demonstrate their great potential applications in nanoelectronic and/or optoelectronic devices. This investigation could stimulate further theoretical and experimental studies on these excellent materials and motivate further explorations of new members of this 2D Janus family.

6.
Chem Biodivers ; 20(1): e202200843, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36574472

RESUMEN

Golden Camellias have recently been used as a food, cosmetic, and traditional medicine in China and Vietnam. Forty-two species have natural distribution in Vietnam, of which thirty-two species were considered endemic species of this country. The morphology of leaves and flowers of these species were similar; therefore, their taxonomic identification usually needed experts and the authentication has often been confused among species. Our study aims to describe the genetic diversity and the relationship of six species Camellia phanii, Camellia tamdaoensis, Camellia tienii, Camellia flava, Camellia petelotii and Camellia euphlebia by using three chloroplast DNA-barcodes: matK, rbcL and trnH-psbA. We also clarified the significant differences in anatomical characteristics of midvein and blade of their leaves, which suggested the possibility to use these criteria in taxonomy. In addition, preliminary chemical profiles of the methanolic extracts of leaves from six Golden Camellias such as total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and chlorogenic acids content (TCGAs) also showed the diversity among them. Interestingly, the discrimination on the catechins profile among six species followed the same tendency with the genetic distance on the phylogeny tree suggesting that catechins (i. e., discriminative catechins) can be biomarkers for the chemotaxonomy of these six Golden Camellias.


Asunto(s)
Camellia , Camellia/química , Vietnam , Flavonoides/análisis , Flores/química , Hojas de la Planta , Código de Barras del ADN Taxonómico , Filogenia , ADN de Plantas/análisis
7.
Clin Infect Dis ; 73(2): e330-e336, 2021 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32564074

RESUMEN

BACKGROUND: Talaromycosis is an invasive mycosis endemic in Southeast Asia and causes substantial morbidity and mortality in individuals with advanced human immunodeficiency virus (HIV) disease. Current diagnosis relies on isolating Talaromyces marneffei in cultures, which takes up to 14 days and is detectable only during late-stage infection, leading to high mortality. METHODS: In this retrospective case-control study, we assessed the accuracy of a novel Mp1p antigen-detecting enzyme immunoassay (EIA) in stored plasma samples of 372 patients who had culture-proven talaromycosis from blood or sterile body fluids (reference standard) and 517 individuals without talaromycosis (338 healthy volunteers; 179 with other infections). All participants were recruited between 2011 and 2017 in Vietnam. RESULTS: Of cases and controls, 66.1% and 75.4%, respectively, were male; the median age was 33 and 37, respectively. All cases were HIV infected; median CD4 count was 10 cells/µL. At an optical density cutoff of 0.5, the specificity was 98.1% (95% CI, 96.3%-99.0%); the sensitivity was superior to blood culture (86.3% [95% CI, 82.3%-89.5%] vs 72.8% [95% CI, 68.0%-77.2%]) (P < .001, McNemar test). The time to diagnosis was 6 hours vs 6.6 ± 3.0 days for blood culture. Paired plasma and urine testing in the same patients (n = 269) significantly increased sensitivity compared to testing plasma alone or testing urine alone (P < .001 and P = .02, respectively, McNemar test). CONCLUSIONS: The Mp1p EIA is highly specific and is superior in sensitivity and time to diagnosis compared to blood culture for the diagnosis of talaromycosis. Paired plasma and urine testing further increases sensitivity, introducing a new tool for rapid diagnosis, enabling early treatment and potentially reducing mortality.


Asunto(s)
Cultivo de Sangre , Adulto , Asia Sudoriental , Estudios de Casos y Controles , Humanos , Técnicas para Inmunoenzimas , Masculino , Micosis , Estudios Retrospectivos , Talaromyces , Vietnam
8.
Am J Physiol Lung Cell Mol Physiol ; 320(4): L600-L614, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33295836

RESUMEN

The growing interest in regulating flavored E-liquids must incorporate understanding of the "flavoring profile" of each E-liquid-which flavorings (flavoring chemicals) are present and at what concentrations not just focusing on the flavor on the label. We investigated the flavoring profile of 10 different flavored E-liquids. We assessed bronchial epithelial cell viability and apoptosis, phagocytosis of bacteria and apoptotic cells by macrophages after exposure to E-cigarette vapor extract (EVE). We validated our data in normal human bronchial epithelial cells (NHBE) and alveolar macrophages (AM) from healthy donors. We also assessed cytokine release and validated in the saliva from E-cigarette users. Increased necrosis/apoptosis (16.1-64.5% apoptosis) in 16HBE cells was flavor dependent, and NHBEs showed an increased susceptibility to flavors. In THP-1 differentiated macrophages phagocytosis was also flavor dependent, with AM also showing increased susceptibility to flavors. Further, Banana and Chocolate were shown to reduce surface expression of phagocytic target recognition receptors on alveolar macrophages. Banana and Chocolate increased IL-8 secretion by NHBE, whereas all 4 flavors reduced AM IL-1ß secretion, which was also reduced in the saliva of E-cigarette users compared with healthy controls. Flavorant profiles of E-liquids varied from simple 2 compound mixtures to complex mixtures containing over a dozen flavorants. E-liquids with high benzene content, complex flavoring profiles, high chemical concentration had the greatest impacts. The Flavorant profile of E-liquids is key to disruption of the airway status quo by increasing bronchial epithelial cell apoptosis, causing alveolar macrophage phagocytic dysfunction, and altering airway cytokines.


Asunto(s)
Apoptosis , Bronquios/patología , Citocinas/metabolismo , Sistemas Electrónicos de Liberación de Nicotina/estadística & datos numéricos , Aromatizantes/efectos adversos , Macrófagos/patología , Fagocitosis , Bronquios/efectos de los fármacos , Bronquios/metabolismo , Humanos , Macrófagos/efectos de los fármacos , Factores de Riesgo
9.
Osteoporos Int ; 32(1): 193-197, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32666144

RESUMEN

Oral bisphosphonates are effective medications for the prevention of fractures in people suffering from osteoporosis. They are associated with gastrointestinal adverse reactions the most severe being an esophageal ulcer. It is unclear if oral bisphosphonates have a similar gastrointestinal safety profile in the hospital setting as in the community setting because hospitalized patients are often bedridden which may hinder proper drug administration. INTRODUCTION: To evaluate the incidence of upper gastrointestinal symptoms in hospitalized patients taking oral bisphosphonate. METHODS: This single-center prospective cohort study included hospitalized adult patients actively taking risedronate or alendronate. Upper gastrointestinal symptoms were actively assessed at the baseline and 1 to 5 h following the administration of the oral bisphosphonate. RESULTS: A total of 298 patients were included in the study. The mean age was 64 ± 15 years. During the follow-up period, gastric and esophageal symptoms affected 32 patients (10.7%). Epigastric burning, dysphagia, and regurgitation were reported in 4.4% (n = 13), 3% (n = 9), 2.7 (n = 8), and 2.3% (n = 7) patients, respectively. Heartburn, retro-sternal pain, and odynophagia were observed in 1.7% (n = 5), 1.7% (n = 5), and 0.3% (n = 1) patients. CONCLUSION: The incidence of adverse reaction was similar to that reported in community trials. The administration of oral bisphosphonate in hospitalized patients does not represent an additional risk for upper gastrointestinal adverse events. Treatment should be optimized during the hospital stay to improve the pharmacological management of osteoporosis.


Asunto(s)
Conservadores de la Densidad Ósea , Difosfonatos , Osteoporosis , Administración Oral , Adulto , Anciano , Alendronato/efectos adversos , Conservadores de la Densidad Ósea/efectos adversos , Difosfonatos/efectos adversos , Humanos , Pacientes Internos , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Osteoporosis/epidemiología , Estudios Prospectivos , Ácido Risedrónico/uso terapéutico
10.
Nanotechnology ; 32(50)2021 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-34517351

RESUMEN

Semiconductor nanocrystals are often proposed as a viable route to improve solar energy conversion in photovoltaics and photoelectrochemical systems. Embedding the nanocrystals in, e.g. a transparent and conducting electrode of a solar cell will promote the photon absorption and subsequent transfer of the generated charge carriers from the nanocrystal, and thereby enhance the function of the electrode. This can be accomplished by embedding a semiconducting nanocrystal with a small bandgap in a transparent conducting oxide (TCO), which is commonly utilized as electrode in new generation solar cells. Here, we demonstrate the incorporation, formation, and functionalization of germanium (Ge) nanocrystals in zinc oxide utilizing ion implantation, where post implantation annealing at 800 °C results in diamond cubic Ge nanocrystals with sizes between 2 and 20 nm. Photoluminecence spectra show a distinct emission around 0.7 eV arising from the Ge nanocrystals, and with additional emission features up to 1.15 eV due to quantum confinement, demonstrating a novel functionalization and tunability of the TCO electrode.

11.
Z Rheumatol ; 80(3): 263-269, 2021 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-33355702

RESUMEN

Rheumatic diseases can lead to a state of malnutrition via a variety of mechanisms. Malnutrition is defined as an insufficient availability of energy, proteins, electrolytes and other nutrients compared to the requirements of a healthy body. After such a catabolic phase, a sudden resupply of the body's full caloric needs can cause life-threatening complications due to an acute paucity of electrolytes and micronutrients. Such metabolic disturbances occurring after the reconstitution of nutrition are termed refeeding syndrome. With sufficient background knowledge about the refeeding syndrome, physicians can prevent serious complications for patients through an adequate reconstitution of caloric intake, the monitoring of relevant laboratory parameters and the supplementation of deficient electrolytes and micronutrients. This review aims to explain the pathological mechanisms driving the refeeding syndrome, to identify risk factors for developing a refeeding syndrome especially in patients with rheumatic diseases and to present strategies to prevent the occurrence of the refeeding syndrome during nutrient reconstitution.


Asunto(s)
Desnutrición , Síndrome de Realimentación , Electrólitos , Humanos , Desnutrición/diagnóstico , Desnutrición/etiología , Desnutrición/prevención & control , Síndrome de Realimentación/diagnóstico , Síndrome de Realimentación/prevención & control , Factores de Riesgo
12.
Biochem Biophys Res Commun ; 530(1): 252-258, 2020 09 10.
Artículo en Inglés | MEDLINE | ID: mdl-32828295

RESUMEN

Human adipose-derived stem cells (ASCs) are a commonly used cell type for cartilage tissue engineering. However, donor-to-donor variability, cell heterogeneity, inconsistent chondrogenic potential, and limited expansion potential can hinder the use of these cells for modeling chondrogenesis, in vitro screening of drugs and treatments for joint diseases, or translational applications for tissue engineered cartilage repair. The goal of this study was to create an immortalized ASC line that showed enhanced and consistent chondrogenic potential for applications in cartilage tissue engineering as well as to provide a platform for investigation of biological and mechanobiological pathways involved in cartilage homeostasis and disease. Starting with the ASC52telo cell line, a hTERT-immortalized ASC line, we used lentivirus to overexpress SOX9, a master regulator of chondrogenesis, and screened several clonal populations of SOX9 overexpressing cells to form a new stable cell line with high chondrogenic potential. One clonal line, named ASC52telo-SOX9, displayed increased GAG and type II collagen synthesis and was found to be responsive to both mechanical and inflammatory stimuli in a manner similar to native chondrocytes. The development of a clonal line such as ASC52telo-SOX9 has the potential to be a powerful tool for studying cartilage homeostasis and disease mechanisms in vitro, and potentially as a platform for in vitro drug screening for diseases that affect articular cartilage. Our findings provide an approach for the development of other immortalized cell lines with improved chondrogenic capabilities in ASCs or other adult stem cells.


Asunto(s)
Condrocitos/citología , Condrogénesis , Células Madre Mesenquimatosas/citología , Línea Celular , Condrocitos/metabolismo , Humanos , Células Madre Mesenquimatosas/metabolismo , FN-kappa B/metabolismo , Factor de Transcripción SOX9/genética , Factor de Transcripción SOX9/metabolismo , Canales Catiónicos TRPV/metabolismo , Regulación hacia Arriba
13.
FASEB J ; 33(1): 358-372, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29985644

RESUMEN

Mesenchymal stem/stromal cells (MSCs) provide an attractive cell source for cartilage repair and cell therapy; however, the underlying molecular pathways that drive chondrogenesis of these populations of adult stem cells remain poorly understood. We generated a rich data set of high-throughput RNA sequencing of human MSCs throughout chondrogenesis at 6 different time points. Our data consisted of 18 libraries with 3 individual donors as biologic replicates, with each library possessing a sequencing depth of 100 million reads. Computational analyses with differential gene expression, gene ontology, and weighted gene correlation network analysis identified dynamic changes in multiple biologic pathways and, most importantly, a chondrogenic gene subset, whose functional characterization promises to further harness the potential of MSCs for cartilage tissue engineering. Furthermore, we created a graphic user interface encyclopedia built with the goal of producing an open resource of transcriptomic regulation for additional data mining and pathway analysis of the process of MSC chondrogenesis.-Huynh, N. P. T., Zhang, B., Guilak, F. High-depth transcriptomic profiling reveals the temporal gene signature of human mesenchymal stem cells during chondrogenesis.


Asunto(s)
Células Madre Adultas/metabolismo , Cartílago/metabolismo , Diferenciación Celular , Condrocitos/metabolismo , Perfilación de la Expresión Génica , Redes Reguladoras de Genes , Células Madre Mesenquimatosas/metabolismo , Células Madre Adultas/citología , Cartílago/citología , Células Cultivadas , Condrocitos/citología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Células Madre Mesenquimatosas/citología , Transducción de Señal , Ingeniería de Tejidos
14.
Pain Med ; 21(12): 3603-3614, 2020 12 25.
Artículo en Inglés | MEDLINE | ID: mdl-31502648

RESUMEN

OBJECTIVE: Although past research has established that men with chronic pain are more likely to misuse prescription pain medications in a myriad of ways compared with women, little is known about men's medication use in the context of their gender role beliefs. The aim of the present study was to examine the role of men's domestic gender role beliefs on their use of prescription pain medication for chronic pain. METHODS: Using a nationally representative data set with 304 men with chronic pain, this study examined a longitudinal moderated mediation model in which pain interference mediates the longitudinal relationship between somatic amplification and prescription pain medication use, with domestic gender role beliefs as a moderator of the aforementioned mediated relationship. RESULTS: Results indicated a significant moderated mediation model in which pain interference fully mediated the relationship between somatic amplification and prescription pain medication use, with men's domestic gender role beliefs moderating this mediated relationship. Specifically, domestic gender role beliefs moderated the relationship between pain interference and prescription pain medication use. Men with higher levels of traditional domestic gender role beliefs strengthened the mediated relationship, contributing to increased prescription pain medication use. CONCLUSIONS: These findings suggest that although men's perceptions of somatic stimuli through its perceived interference contribute to their medication use, the extent to which they consume prescription pain medication depends on their beliefs in domestic gender roles during chronic pain.


Asunto(s)
Dolor Crónico , Medicamentos bajo Prescripción , Dolor Crónico/tratamiento farmacológico , Femenino , Identidad de Género , Rol de Género , Humanos , Masculino , Medicamentos bajo Prescripción/uso terapéutico , Prescripciones
15.
J Couns Psychol ; 67(5): 568-579, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31855027

RESUMEN

The cross-cultural validity of a modified version of psychology of working theory (PWT; Duffy, Blustein, Diemer, & Autin, 2016) was tested in samples of United States (n = 346) and Korean (n = 319) undergraduates. Participants completed measures of economic resources, work volition, career adaptability, occupational engagement, and future decent work perceptions. The results illustrated measurement invariance between the two samples. Thus, the hypothesized models were tested separately in the two samples and the results were compared regarding parameter significance, direction, and magnitude. Overall, the modified model generally fit well with both samples. However, there were notable cross-cultural differences: economic resources significantly predicted work volition, occupational engagement, and future decent work perceptions only in the United States sample and the future decent work perceptions and occupational engagement were negatively associated in the Korean sample. Explanations about the cross-cultural differences and invariances were provided and practical and research implications were discussed. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Asunto(s)
Movilidad Laboral , Comparación Transcultural , Ocupaciones/tendencias , Estudiantes/psicología , Universidades/tendencias , Volición , Adolescente , Adulto , Femenino , Humanos , Masculino , Ocupaciones/economía , República de Corea/etnología , Estados Unidos/etnología , Universidades/economía , Adulto Joven
16.
Artículo en Inglés | MEDLINE | ID: mdl-30642927

RESUMEN

LYS228 has potent antibacterial activity against carbapenem-resistant strains of Enterobacteriaceae LYS228 was efficacious in neutropenic thigh models established with Klebsiella pneumoniae producing KPC-2 or NDM-1; pretreatment with uranyl nitrate considerably shifted calculated static doses of LYS228. In murine ascending pyelonephritis, LYS228 reduced bacterial burden in kidney, urine, and bladder. The successful treatment of murine infection models established with carbapenem-resistant K. pneumoniae further supports the clinical development of LYS228.


Asunto(s)
Antibacterianos/farmacología , Proteínas Bacterianas/metabolismo , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Infecciones por Klebsiella/tratamiento farmacológico , Klebsiella pneumoniae/efectos de los fármacos , Monobactamas/farmacología , beta-Lactamasas/metabolismo , Animales , Enterobacteriaceae Resistentes a los Carbapenémicos/metabolismo , Carbapenémicos/farmacología , Modelos Animales de Enfermedad , Femenino , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae/metabolismo , Ratones , Pielonefritis/tratamiento farmacológico , Pielonefritis/microbiología
17.
Clin Exp Immunol ; 195(2): 277-285, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30303525

RESUMEN

Immunosuppression therapies including corticosteroids fail to prevent bronchiolitis obliterans syndrome (BOS), primarily a disease of the small airways, following lung transplantation. We reported increases in steroid-resistant proinflammatory lymphocytes and their loss of histone deacetylase 2 (HDAC2), an important mediator of steroid action, in the blood of stable lung transplant recipients. We noted similar increases in the steroid-resistant lymphocytes in both the blood and small airways in BOS compared with the large airways. We hypothesized that these small airway cells would also exhibit a loss of HDAC2, and that these changes could be reversed by treatment with theophylline (HDAC2 activator). Blood, bronchoalveolar lavage and large and small airway brushings were collected from lung transplant patients with BOS (n = 12) or stable lung function (n = 18) and healthy aged-matched controls (n = 13). Intracellular proinflammatory cytokines [interferon (IFN-γ) and tumour necrosis factor (TNF)-α and HDAC2 were measured in CD8+ T, natural killer (NK) T-like and NK cells from cultured small airway brushings ± 5 mg/l theophylline ± 1 µM prednisolone using flow cytometry. Increased small airway CD8 T, NK T-like and NK cells were identified in BOS versus stable transplant and controls. In BOS, these cells exhibited increased IFN-γ/TNF-α and a loss of HDAC2. HDAC2 expression by small airway CD8+ T cells correlated with forced expiratory volume in 1 s (FEV1 ) (R = 0·880, P = 0·031). Theophylline and prednisolone synergistically up-regulated HDAC2 in CD8+ T cells. BOS is associated with loss of HDAC2 from steroid-resistant proinflammatory CD8+ T, NK T-like and NK cells in the small airways. Therapeutically increasing HDAC2 in these lymphocytes may reduce steroid resistance and improve graft survival.


Asunto(s)
Broncodilatadores/farmacología , Linfocitos T CD8-positivos/metabolismo , Histona Desacetilasa 2/metabolismo , Células Asesinas Naturales/metabolismo , Alveolos Pulmonares/inmunología , Teofilina/farmacología , Bronquiolitis Obliterante/patología , Bronquiolitis Obliterante/prevención & control , Linfocitos T CD4-Positivos/inmunología , Supervivencia de Injerto/efectos de los fármacos , Histona Desacetilasa 2/análisis , Humanos , Interferón gamma/análisis , Trasplante de Pulmón/efectos adversos , Persona de Mediana Edad , Prednisolona/farmacología , Factor de Necrosis Tumoral alfa/análisis
18.
Neurobiol Learn Mem ; 161: 72-82, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30930287

RESUMEN

Beta-adrenergic receptor (b-AR) activation by noradrenaline (NA) enhances memory formation and long-term potentiation (LTP), a form of synaptic plasticity characterized by an activity-dependent increase in synaptic strength. LTP is believed to be a cellular mechanism for contextual learning and memory. In the mammalian hippocampus, LTP can be observed at multiple synaptic pathways after strong stimulation of a single synaptic pathway. This heterosynaptic LTP is believed to involve synaptic tagging of active synapses and capture of plasticity-related proteins that enable heterosynaptic transfer of persistent potentiation. These processes may permit distinct neural pathways to associate information transmitted by separate, but convergent, synaptic inputs. We had previously shown that transcription and epigenetic modifications were necessary for stabilization of homosynaptic LTP. However, it is unclear whether transfer of LTP to a second, heterosynaptic pathway involves b-ARs signalling to the nucleus. Using electrophysiologic recordings in area CA1 of murine hippocampal slices, we show here that pharmacologically inhibiting b-AR activation, transcription, DNA methyltransferase or histone acetyltransferase activation, prevents stabilization of heterosynaptic LTP. Our data suggest that noradrenergic stabilization of heterosynaptic ("tagged") LTP requires not only transcription, but specifically, DNA methylation and histone acetylation. NA promotes stable heterosynaptic plasticity through engagement of nuclear processes that may contribute to prompt consolidation of short-term memories into resilient long-term memories under conditions when the brain's noradrenergic system is recruited.


Asunto(s)
Región CA1 Hipocampal/fisiología , Epigénesis Genética/fisiología , Potenciales Postsinápticos Excitadores/fisiología , Potenciación a Largo Plazo/fisiología , Norepinefrina/fisiología , Receptores Adrenérgicos beta/fisiología , Transducción de Señal/fisiología , Antagonistas Adrenérgicos beta/farmacología , Animales , Región CA1 Hipocampal/efectos de los fármacos , Citidina/análogos & derivados , Citidina/farmacología , Metilación de ADN/efectos de los fármacos , Epigénesis Genética/efectos de los fármacos , Potenciales Postsinápticos Excitadores/efectos de los fármacos , Histona Acetiltransferasas/antagonistas & inhibidores , Inhibidores de Histona Desacetilasas/farmacología , Potenciación a Largo Plazo/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Propranolol/farmacología , Receptores Adrenérgicos beta/efectos de los fármacos , Transducción de Señal/efectos de los fármacos
19.
Ann Oncol ; 29(2): 386-391, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29267861

RESUMEN

Background: Androgens are generally immunosuppressive, and men with untreated hypogonadism are at increased risk for autoimmune conditions. To date, there has been no evidence linking androgen deprivation therapy (ADT) to autoimmune diseases, including rheumatoid arthritis (RA). We investigated the association between ADT and RA in patients with prostate cancer. Patients and methods: We identified 105 303 men age 66 years or older who were diagnosed with stages I-III prostate cancer from 1992 through 2006 using the Surveillance, Epidemiology, and End Results-Medicare linked database, excluding patients with a history of RA. χ2 test was used to compare 5-year Kaplan-Meier rates of RA diagnoses. Competing risk Cox regression using inverse probability of treatment weighting was utilized to examine the association between pharmacologic ADT and diagnosis of RA. Results: The 43% of patients (N = 44 785) who received ADT experienced a higher 5-year rate of RA diagnoses compared with men who did not (5.4% versus 4.4%, P < 0.001). Receipt of any ADT was associated with a 23% increased risk of being diagnosed with RA (hazard ratio 1.23, 95% confidence interval 1.09-1.40, P = 0.001). The risk of being diagnosed with RA increased with a longer duration of ADT, from 19% with 1-6 months and 29% with 7-12 months to 33% with ≥13 months (Ptrend < 0.001). Conclusions: Consistent with the immunosuppressive properties of androgens, we demonstrated for the first time that ADT was associated with an elevated risk of being diagnosed with RA in this large cohort of elderly men with prostate cancer. The risk was higher with a longer duration of ADT. Linking ADT to an increased risk of being diagnosed with an autoimmune condition adds to mounting evidence of the adverse effects of ADT that should prompt physicians to thoughtfully weigh its risks and benefits.


Asunto(s)
Antagonistas de Andrógenos/efectos adversos , Antineoplásicos Hormonales/efectos adversos , Artritis Reumatoide/inducido químicamente , Neoplasias de la Próstata/tratamiento farmacológico , Anciano , Anciano de 80 o más Años , Artritis Reumatoide/epidemiología , Humanos , Masculino , Modelos de Riesgos Proporcionales , Programa de VERF
20.
Clin Exp Immunol ; 192(2): 242-250, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29352737

RESUMEN

Immunosuppressive therapy fails to suppress the production of proinflammatory cytokines, particularly by CD8+ T cells, in stable lung transplant recipients and those undergoing chronic rejection, suggesting that some patients may become relatively resistant to immunosuppressants such as glucocorticoids (GC). We have shown loss of GC receptor (GCR) from the CD8+ cells, and we hypothesized that the drug membrane efflux pump, p-glycoprotein-1 (Pgp), may also be involved in lymphocyte steroid resistance following lung transplant. Pgp/GCR expression and interferon (IFN)-γ/tumour necrosis factor (TNF)-α proinflammatory cytokine production was measured in blood lymphocytes from 15 stable lung transplant patients, 10 patients with bronchiolitis obliterans syndrome (BOS) and 10 healthy aged-matched controls (± prednisolone ± Pgp inhibitor, cyclosporin A ± GCR activator, Compound A) using flow cytometry. Both Pgp+ and Pgp- lymphocyte subsets from all subjects produced IFN-γ/TNF-α proinflammatory cytokines. Pgp expression was increased in CD8+ Pgp+ T cells and correlated with IFN-γ/TNF-α expression and BOS grade. Reduced GCR was observed in CD8+ Pgp- T, natural killer (NK) T-like and NK cells from stable patients compared with controls, and reduced further in CD8+ Pgp- T cells in BOS. The addition of 2·5 ng/ml cyclosporin A and 1 µM prednisolone inhibit IFN-γ/TNF-α production significantly by CD8+ Pgp+ T cells from BOS patients. The addition of 10 µM Compound A and 1 µM prednisolone inhibit IFN-γ/TNF-α production significantly by CD8+ Pgp- T cells from BOS patients. BOS is associated with increased Pgp expression and loss of GCR from steroid-resistant proinflammatory CD8+ T cells. Treatments that inhibit Pgp and up-regulate GCR in CD8+ T cells may improve graft survival.


Asunto(s)
Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Bronquiolitis Obliterante/inmunología , Linfocitos T CD8-positivos/metabolismo , Trasplante de Pulmón , Receptores de Glucocorticoides/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Adulto , Bronquiolitis Obliterante/genética , Linfocitos T CD8-positivos/efectos de los fármacos , Resistencia a Medicamentos , Citometría de Flujo , Humanos , Interferón gamma/sangre , Células Asesinas Naturales/efectos de los fármacos , Células Asesinas Naturales/metabolismo , Persona de Mediana Edad , Receptores de Glucocorticoides/genética , Esteroides/administración & dosificación , Factor de Necrosis Tumoral alfa/sangre , Miembro 4 de la Subfamilia B de Casete de Unión a ATP
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