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1.
Klin Monbl Augenheilkd ; 236(6): 806-815, 2019 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-29514380

RESUMEN

INTRODUCTION: Our study compares the biomechanical properties of the cornea in patients with long-term pre-existing (for at least 10 years) systemic sclerosis (SSc) with those of healthy suspects. MATERIAL/METHODS: The examination was performed in 14 systemic SSc patients and 38 healthy volunteers. Non-invasive assessment of corneal biomechanical parameters, including central corneal thickness (CCT), corneal hysteresis (CH) and corneal resistance factor (CRF), was performed in one randomised study eye in accordance with a standardised protocol. Intraocular pressure (IOP) values were analysed using different measuring techniques, including Goldmann applanation tonometry (GAT), dynamic contour tonometry (DCT) and Ocular Response Analyzer® (ORA)-based non-contact tonometry (NCT), GAT-correlated IOP (IOPgat) and CCT-compensated-IOP (IOPcc). RESULTS: When measured with DCT and ORA-based NCT, IOP levels were significantly lower in SSc patients than in the control group (DCT IOP: p = 0.048, NCT IOPgat: p = 0.002, NCT IOPcc: p < 0.001). CCT was also significantly reduced in the SSc (p = 0.001). There were no statistically significant differences between the groups in CH and CRF. The difference between the corrected values (CHcorr - CRFcorr) was negative in the two groups. This was slightly lower for the SSc patients (delta = - 0.83) than for the control group (delta = - 0.66). For SSc patients, there were highly significant negative correlations between CH and CRF and between CHcorr and CRFcorr. In contrast, in the control group there was a non-significant positive correlation between age and biomechanical properties. CONCLUSION: In the course of the disease SSc leads to various alterations in connective tissue, which can also involve corneal tissue. CCT becomes significantly thinner and simultaneously partially loses elastic properties and gains viscosity. This accounts for reduced IOP values with dynamic contour tonometry as well as with ORA-tonometry (Goldmann-correlated IOP, CCT-compensated IOP). This distinct pre-existing significant negative correlation between age and CH and CRF values in patients with SSc could be due to slight regression of the viscous components and diminution of corneal damping capacity.


Asunto(s)
Fenómenos Biomecánicos , Córnea , Esclerodermia Sistémica , Estudios de Casos y Controles , Córnea/patología , Enfermedades de la Córnea/etiología , Enfermedades de la Córnea/patología , Humanos , Presión Intraocular , Esclerodermia Sistémica/complicaciones , Tonometría Ocular , Viscosidad
2.
Proc Natl Acad Sci U S A ; 108(41): 17213-8, 2011 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-21969592

RESUMEN

Stress has been identified as a major causal factor for many mental disorders. However, our knowledge about the chain of molecular and cellular events translating stress experience into altered behavior is still rather scant. Here, we have characterized a murine ortholog of the putative tumor suppressor gene DRR1 as a unique stress-induced protein in brain. It binds to actin, promotes bundling and stabilization of actin filaments, and impacts on actin-dependent neurite outgrowth. Endogenous DRR1 localizes to some, but not all, synapses, with preference for the presynaptic region. Hippocampal virus-mediated enhancement of DRR1 expression reduced spine density, diminished the probability of synaptic glutamate release, and altered cognitive performance. DRR1 emerges as a protein to link stress with actin dynamics, which in addition is able to act on synaptic function and cognition.


Asunto(s)
Cognición/fisiología , Sinapsis/fisiología , Proteínas Supresoras de Tumor/fisiología , Actinas/metabolismo , Animales , Conducta Animal/fisiología , Encéfalo/citología , Encéfalo/fisiología , Genes Supresores de Tumor , Células HEK293 , Humanos , Masculino , Aprendizaje por Laberinto/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neuritas/metabolismo , Neuritas/ultraestructura , Unión Proteica , Estrés Fisiológico , Proteínas Supresoras de Tumor/genética
3.
Biochem J ; 448(1): 93-102, 2012 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-22880885

RESUMEN

The discovery of epigenetic processes as possible pivotal regulatory mechanisms in psychiatric diseases raised the question of how psychoactive drugs may impact the epigenetic machinery. In the present study we set out to explore the specificity and the mode of action of the reported inhibitory effect of the TCA (tricyclic antidepressant) amitriptyline on DNMT (DNA methyltransferase) activity in primary astrocytes from the rat cortex. We found that the impact on DNMT was shared by another TCA, imipramine, and by paroxetine, but not by venlafaxine or the mood stabilizers carbamazepine and valproic acid. DNMT activity in subventricular neural stem cells was refractory to the action of ADs (antidepressants). Among the established DNMTs, ADs primarily targeted DNMT1. The reduction of enzymatic DNMT1 activity was neither due to reduced DNMT1 expression nor due to direct drug interference. We tested putative DNMT1-inhibitory mechanisms and discovered that a known stimulator of DNMT1, the histone methyltransferase G9a, exhibited decreased protein levels and interactions with DNMT1 upon AD exposure. Adding recombinant G9a completely reversed the AD repressive effect on DNMT1 function. In conclusion, the present study presents a model where distinct ADs affect DNMT1 activity via G9a with important repercussions for possible novel treatment regimes.


Asunto(s)
Antidepresivos/farmacología , ADN (Citosina-5-)-Metiltransferasas/antagonistas & inhibidores , Metilación de ADN/efectos de los fármacos , N-Metiltransferasa de Histona-Lisina/antagonistas & inhibidores , N-Metiltransferasa de Histona-Lisina/metabolismo , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Animales , Astrocitos/efectos de los fármacos , Astrocitos/enzimología , Astrocitos/fisiología , Carbamazepina/farmacología , Células Cultivadas/efectos de los fármacos , Células Cultivadas/enzimología , Células Cultivadas/fisiología , Corteza Cerebral/citología , Corteza Cerebral/embriología , Citalopram/farmacología , Ciclohexanoles/farmacología , ADN (Citosina-5-)-Metiltransferasa 1 , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Inhibidores Enzimáticos/farmacología , Glucolípidos/farmacología , N-Metiltransferasa de Histona-Lisina/farmacología , Imipramina/farmacología , Indoles/farmacología , Maleimidas/farmacología , Ratones , Proteínas del Tejido Nervioso/metabolismo , Células-Madre Neurales/efectos de los fármacos , Células-Madre Neurales/enzimología , Células-Madre Neurales/fisiología , Neuronas/efectos de los fármacos , Neuronas/enzimología , Neuronas/fisiología , Paroxetina/farmacología , Mapeo de Interacción de Proteínas , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Clorhidrato de Venlafaxina
4.
GMS J Med Educ ; 40(1): Doc3, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36923317

RESUMEN

Aim: Interprofessional collaboration is particularly relevant to patient safety in outpatient care with polypharmacy. The educational project "PILLE" is meant to give medical and pharmacy students an understanding of the roles and competencies needed for cooperation in the provision of healthcare and to enable interprofessional learning. Method: The curriculum is aimed at pharmacy and medical students and was developed in six steps according to the Kern cycle. It is comprised of an interprofessional seminar, a joint practical training in a simulated pharmacy, and a tandem job shadowing at a primary care practice. The project was implemented in three stages due to the pandemic: The interprofessional online seminar based on the ICAP model and the digital inverted classroom was held in the 2020 winter semester; the interprofessional practical training was added in the 2021 summer semester; and the interprofessional tandem job shadowing at a primary care practice in the 2021 winter semester. Attitudes toward interprofessional learning, among other things, was measured in the evaluation using the SPICE-2D questionnaire (Student Perceptions of Physician-Pharmacist Interprofessional Clinical Education). Results: In the first three semesters, a total of 105 students (46 pharmacy, 59 medicine) participated in the project, of which 78 participated in the evaluation (74% response rate). The students stated, in particular, that they had learned about the competencies and roles of the other profession and desired additional and more specific preparatory materials for the course sessions. The SPICE-2D questionnaire showed high values for both groups of students already in the pre-survey and these increased further as a result of the project. Conclusion: Joint case-based learning could be implemented under the conditions imposed by the pandemic. Online teaching is a low-threshold means to enable interprofessional exchange.


Asunto(s)
Estudiantes de Medicina , Estudiantes de Farmacia , Humanos , Polifarmacia , Curriculum , Aprendizaje
5.
Beilstein J Org Chem ; 8: 1246-55, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23019455

RESUMEN

Starting from the enantiomers of limonene, all eight stereoisomers of trans-fused dihydronepetalactones were synthesized. Key compounds were pure stereoisomers of 1-acetoxymethyl-2-methyl-5-(2-hydroxy-1-methylethyl)-1-cyclopentene. The stereogenic center of limonene was retained at position 4a of the target compounds and used to stereoselectively control the introduction of the other chiral centers during the synthesis. Basically, this approach could also be used for the synthesis of enantiomerically pure trans-fused iridomyrmecins. Using synthetic reference samples, the combination of enantioselective gas chromatography and mass spectrometry revealed that volatiles released by the endohyperparasitoid wasp Alloxysta victrix contain the enantiomerically pure trans-fused (4R,4aR,7R,7aS)-dihydronepetalactone as a minor component, showing an unusual (R)-configured stereogenic center at position 7.

6.
Beilstein J Org Chem ; 8: 1256-64, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-23019456

RESUMEN

Following our earlier approach to the synthesis of dihydronepetalactones, all eight stereoisomers of trans-fused iridomyrmecins were synthesized starting from the enantiomers of limonene. Combined gas chromatography and mass spectrometry including enantioselective gas chromatography revealed that volatiles released by the endohyperparasitoid wasp Alloxysta victrix contain (4S,4aR,7S,7aR)-iridomyrmecin of 95-97% ee and stereochemically pure (4S,4aS,7R,7aS)-iridomyrmecin as a minor component.

7.
J Anal Toxicol ; 46(5): 540-548, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-33851996

RESUMEN

Rising numbers of psychoactive tryptamine derivatives have become available on the drug market over the last decade, making these naturally occurring or synthetically manufactured compounds highly relevant for forensic analyses. One of these compounds is 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT), a constituent of the dried poison of Incilius alvarius (Colorado River toad), which has a history of ritual and/or recreational use. Still, comprehensive and validated qualitative as well as quantitative analytical data on the psychoactive components of this poison are scarce. In this study, samples of the poison of Incilius alvarius were collected from live toads in the Sonoran Desert, Arizona (USA), and analyzed with a set of complementary methods. Acetone/water (70/30, v/v) proved to be the solvent of choice for the extraction of tryptamine derivatives. Trace compounds were enriched, and overload with 5-MeO-DMT was prevented by chromatographic separation of 5-MeO-DMT prior to qualitative analyses. The method for quantification was validated. Attenuated total reflection-Fourier transform infrared spectroscopy was suitable to identify 5-MeO-DMT as the main tryptamine in samples of the poison. The combined evaluation of analytical data gained from gas chromatography-mass spectrometry (GC-MS), high-performance liquid chromatography-quadrupole time-of-flight high-resolution MS (HPLC-qToF-HRMS) and HPLC-MS-MS confirmed the presence of 5-MeO-DMT, 5-MeO-N-methyltryptamine, 5-MeO-tryptamine, 5-MeO-tryptophol, 2-(5-methoxy-1H-indol-3-yl)-acetic-acid (5-MIAA), 5-HO-N-methyltryptamine, bufotenin, DMT and tryptophan. For the first time, 5-MeO-tryptamine and two positional isomers of hydroxylated MeO-DMT were detected in the poison of Incilius alvarius. The tryptamine present in the highest concentrations was 5-MeO-DMT (mean ± SD: 410,000 ± 30,000 µg/g). Mean concentrations of 5-MeO-tryptamine (490 ± 260 µg/g), 5-HO-N-methyltryptamine (270 ± 120 µg/g), bufotenin (2,800 ± 1,900 µg/g) and DMT (250 ± 80 µg/g) showed a relatively high variability between individual samples. The comprehensive analytical reference data of Incilius alvarius poison presented here might prove useful for forensic chemists.


Asunto(s)
Bufotenina , Venenos , Animales , Bufonidae , Metoxidimetiltriptaminas , Triptaminas
8.
Infect Dis Ther ; 11(1): 617-628, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34751941

RESUMEN

BACKGROUND: Antimicrobial stewardship (AMS) programs aim to secure the rational prescription of antibiotics through implementing department- or hospital-level activities. Infectious disease (ID) specialists improve the quality of care and outcomes in infection patients predominantly by individual consultations and patient-level interventions. While hospital AMS programs are established to various extents in Germany, ID specialist services are rarely available in this country. In the ID ROLL OUT study, we will implement and evaluate hospital-level AMS tools with and without ID specialist services in secondary and tertiary care hospitals. We aim to identify means to comprehensively and sustainably improve the quality of care of patients with infectious diseases. METHODS: This project is a clustered, two-armed intervention study, which will be conducted in ten secondary and tertiary (non-university) care hospitals in Germany. The intervention groups are stratified by key characteristics of the hospitals. We will compare two interventional strategies: implementation of AMS teams and implementation of AMS teams combined with the activities of ID specialists (AMS + IDS). PLANNED OUTCOMES: The primary outcome is the quality of care as measured in changes in a Staphylococcus aureus bacteremia (SAB) score (as an indicator of difficult-to-treat infections) and a community-acquired pneumonia (CAP) score (as an indicator of common infections) compared to a baseline pre-interventional period. Our secondary outcomes comprise patient- and hospital-level outcomes, such as the quality and frequency of antibiotic treatment, in-hospital mortality, duration of hospitalization, and C. difficile incidence (associated diarrhea episodes). The study may provide urgently needed key information for the aspired advancement of ID care in Germany. TRIAL REGISTRATION: DRKS00023710 (registered on 9th April 2021).

9.
Eur J Hum Genet ; 15(8): 837-42, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17299436

RESUMEN

The Rubinstein-Taybi syndrome (RSTS, MIM 180849), a dominant Mendelian disorder with typical face, short stature, skeletal abnormalities, and mental retardation, is usually caused by heterozygous mutations of the CREBBP gene, but recently, EP300 gene mutations were reported in three individuals. Using quantitative PCR (for the CREBBP and EP300 genes) and genomic sequencing (for the EP300 gene), we studied here 13 patients who had shown no mutation after genomic sequencing of the CREBBP gene in a previous investigation. Two new disease-causing mutations were identified, including a partial deletion of CREBBP and a 1-bp deletion in EP300, c.7100delC (p.P2366fsX2401). The 1-bp deletion represents the fourth EP300 mutation reported to date and was identified in a patient with non-classical RSTS. Based on the very similar structure of the CREBBP and EP300 genes and the higher rate of single-nucleotide polymorphisms in EP300 (2.23 per individual) as compared to CREBBP (0.71 per individual) (P>0.001, Wilcoxon test), it may be assumed that EP300 gene mutations should be as frequent as CREBBP gene mutations. Based on the location of the EP300 gene mutations identified so far (outside the histone acetyl transferase domain) and the observed (although not very striking) phenotypical differences with the EP300 mutations, we propose that most EP300 mutations could be associated with other phenotypes, not classical RSTS.


Asunto(s)
Proteína p300 Asociada a E1A/genética , Síndrome de Rubinstein-Taybi/genética , Adolescente , Adulto , Femenino , Humanos , Fenotipo
10.
Syst Rev ; 6(1): 2, 2017 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-28086971

RESUMEN

BACKGROUND: There is wide agreement that there is a lack of attention to health in municipal environmental policy-making, such as urban planning and regeneration. Explanations for this include differing professional norms between health and urban environment professionals, system complexity and limited evidence for causality between attributes of the built environment and health outcomes. Data from urban health indicator (UHI) tools are potentially a valuable form of evidence for local government policy and decision-makers. Although many UHI tools have been specifically developed to inform policy, there is poor understanding of how they are used. This study aims to identify the nature and characteristics of UHI tools and their use by municipal built environment policy and decision-makers. METHODS: Health and social sciences databases (ASSIA, Campbell Library, EMBASE, MEDLINE, Scopus, Social Policy and Practice and Web of Science Core Collection) will be searched for studies using UHI tools alongside hand-searching of key journals and citation searches of included studies. Advanced searches of practitioner websites and Google will also be used to find grey literature. Search results will be screened for UHI tools, and for studies which report on or evaluate the use of such tools. Data about UHI tools will be extracted to compile a census and taxonomy of existing tools based on their specific characteristics and purpose. In addition, qualitative and quantitative studies about the use of these tools will be appraised using quality appraisal tools produced by the UK National Institute for Health and Care Excellence (NICE) and synthesised in order to gain insight into the perceptions, value and use of UHI tools in the municipal built environment policy and decision-making process. This review is not registered with PROSPERO. DISCUSSION: This systematic review focuses specifically on UHI tools that assess the physical environment's impact on health (such as transport, housing, air quality and greenspace). This study will help indicator producers understand whether this form of evidence is of value to built environment policy and decision-makers and how such tools should be tailored for this audience. SYSTEMATIC REVIEW REGISTRATION: N/A.


Asunto(s)
Planificación de Ciudades/métodos , Indicadores de Salud , Formulación de Políticas , Política Pública , Remodelación Urbana/métodos , Toma de Decisiones , Humanos , Revisiones Sistemáticas como Asunto , Salud Urbana
12.
CNS Neurol Disord Drug Targets ; 12(8): 1194-204, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24040815

RESUMEN

In recent years, it has been established that environmental stress leaves enduring traces at distinct sites on the chromatin, accompanied by permanent alterations of gene transcription. This process depends on duration and extent of the discharge of stress hormones. Here, we aimed at identifying genes that are both regulated by the glucocorticoid receptor (GR) and display epigenetic features of transcriptional control. We used neuronal Neuro-2a cells as model system; cells were transiently transfected with GR and exposed to dexamethasone (Dex) for 2 days, either under conditions of cell proliferation or after serum deprivation-induced growth arrest. In parallel, Neuro-2a cells were treated with the histone deacetylase inhibitor trichostatin A. Comparison of gene expression profiles obtained from whole-genome microarray analyses revealed a network of genes that were GR-dependent and under control of epigenetic factors. Gene set enrichment analysis was performed in order to obtain insight into functional mechanisms implicated in stress hormone physiology. Dex response varied between proliferating and growth-arrested cells; enrichment was found for genes associated with metabolic pathways in proliferating cells, and for genes linked to inflammation in growth-arrested cells. The set of genes that were regulated by Dex under both growth conditions (proliferation and arrest) as well as by trichostatin A - (under cell proliferation) was enriched in mRNA transcripts encoding proteins which play a role in development and homeostasis. In summary, this study introduces a conceptual approach and incipient proof-of-concept for the identification of candidate genes that might be epigenetically programmed by activated GR.


Asunto(s)
Proliferación Celular , Epigénesis Genética/genética , Redes Reguladoras de Genes/genética , Neuronas/fisiología , Receptores de Glucocorticoides/genética , Animales , Línea Celular , Proliferación Celular/efectos de los fármacos , Dexametasona/farmacología , Epigénesis Genética/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Inhibidores de Crecimiento/farmacología , Ratones , Neuronas/efectos de los fármacos
13.
F1000 Med Rep ; 5: 3, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23413369

RESUMEN

Cataract surgery is one of the oldest and the most frequent outpatient clinic operations in medicine performed worldwide. The clouded human crystalline lens is replaced by an artificial intraocular lens implanted into the capsular bag. During the last six decades, cataract surgery has undergone rapid development from a traumatic, manual surgical procedure with implantation of a simple lens to a minimally invasive intervention increasingly assisted by high technology and a broad variety of implants customized for each patient's individual requirements. This review discusses the major advances in this field and focuses on the main challenge remaining - the treatment of presbyopia. The demand for correction of presbyopia is increasing, reflecting the global growth of the ageing population. Pearls and pitfalls of currently applied methods to correct presbyopia and different approaches under investigation, both in lens implant technology and in surgical technology, are discussed.

14.
Neuropsychopharmacology ; 36(8): 1754-68, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21508931

RESUMEN

In the search for antidepressants' (ADs') mechanisms of action beyond their influence on monoaminergic neurotransmission, we analyzed the effects of three structurally and pharmacologically different ADs on autophagic processes in rat primary astrocytes and neurons. Autophagy has a significant role in controlling protein turnover and energy supply. Both, the tricyclic AD amitriptyline (AMI) and the selective serotonin re-uptake inhibitor citalopram (CIT) induced autophagy as mirrored by pronounced upregulation and cellular redistribution of the marker LC3B-II. Redistribution was characterized by formation of LC3B-II-positive structures indicative of autophagosomes, which associated with AVs in a time-dependent manner. Deletion of Atg5, representing a central mediator of autophagy in MEFs, led to abrogation of AMI-induced LC3B-I/II conversion. By contrast, VEN, a selective serotonin and noradrenaline reuptake inhibitor, did not promote autophagic processes in either cell type. The stimulatory impact of AMI on autophagy partly involved class-III PI3 kinase-dependent pathways as 3-methyladenine slightly diminished the effects of AMI. Autophagic flux as defined by autophagosome turnover was vastly undisturbed, and degradation of long-lived proteins was augmented upon AMI treatment. Enhanced autophagy was dissociated from drug-induced alterations in cholesterol homeostasis. Subsequent to AMI- and CIT-mediated autophagy induction, neuronal and glial viability decreased, with neurons showing signs of apoptosis. In conclusion, we report that distinct ADs promote autophagy in neural cells, with important implications on energy homeostasis.


Asunto(s)
Antidepresivos/farmacología , Astrocitos/fisiología , Autofagia/fisiología , Colesterol/fisiología , Homeostasis/fisiología , Transducción de Señal/fisiología , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Autofagia/efectos de los fármacos , Línea Celular , Células Cultivadas , Homeostasis/efectos de los fármacos , Ratones , Ratones Noqueados , Ratas , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacos
15.
Neuropsychopharmacology ; 35(3): 792-805, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19924110

RESUMEN

Aberrant biochemical processes in the brain frequently go along with subtle shifts of the cellular epigenetic profile that might support the pathogenic progression of psychiatric disorders. Although recent reports have implied the ability of certain antidepressants and mood stabilizers to modulate epigenetic parameters, studies comparing the actions of these compounds under the same conditions are lacking. In this study, we screened amitriptyline (AMI), venlafaxine, citalopram, as well as valproic acid (VPA), carbamazepine, and lamotrigine for their potential actions on global and local epigenetic modifications in rat primary astrocytes. Among all drugs, VPA exposure evoked the strongest global chromatin modifications, including histone H3/H4 hyperacetylation, 2MeH3K9 hypomethylation, and DNA demethylation, as determined by western blot and luminometric methylation analysis, respectively. CpG demethylation occurred independently of DNA methyltransferase (DNMT) suppression. Strikingly, AMI also induced slight cytosine demethylation, paralleled by the reduction in DNMT enzymatic activity, without affecting the global histone acetylation status. Locally, VPA-induced chromatin modifications were reflected at the glutamate transporter (GLT-1) promoter as shown by bisulfite sequencing and acetylated histone H4 chromatin immunoprecipitation analysis. Distinct CpG sites in the distal part of the GLT-1 promoter were demethylated and enriched in acetylated histone H4 in response to VPA. For the first time, we could show that these changes were associated with an enhanced transcription of this astrocyte-specific gene. In contrast, AMI failed to stimulate GLT-1 transcription and to alter promoter methylation levels. In conclusion, VPA and AMI globally exerted chromatin-modulating activities using different mechanisms that divergently precipitated at an astroglial gene locus.


Asunto(s)
Amitriptilina/farmacología , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Cromatina/metabolismo , Regiones Promotoras Genéticas/efectos de los fármacos , Ácido Valproico/farmacología , Animales , Animales Recién Nacidos , Células Cultivadas , Cromatina/genética , Metilación de ADN/efectos de los fármacos , Metilación de ADN/fisiología , Regiones Promotoras Genéticas/fisiología , Ratas , Ratas Sprague-Dawley
17.
Curr Opin Drug Discov Devel ; 12(4): 543-61, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19562650

RESUMEN

Neuropathic pain is a chronic disease, which impacts millions of individuals worldwide. The condition is currently treated with several drugs that provide pain relief that is inconsistent and complicated by CNS or cardiovascular (CV) side effects. Voltage-gated sodium channels (VGSCs) and voltage-gated calcium channels (VGCCs) are of particular interest as targets for neuropathic pain because they control electrical signals in both the central and peripheral nervous system. Recent research has demonstrated that the expression of voltage-gated ion channels changes significantly under conditions of neuropathic pain in rodents and humans. Selective modulation of the channels involved in the pathology of the disease, while sparing the channels that are essential for normal nociception, offers promising opportunities for therapeutic intervention. This review summarizes recent developments of small molecules that target VGSCs and VGCCs.


Asunto(s)
Bloqueadores de los Canales de Calcio/farmacología , Dolor/tratamiento farmacológico , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Bibliotecas de Moléculas Pequeñas/farmacología , Bloqueadores de los Canales de Sodio/farmacología , Animales , Bloqueadores de los Canales de Calcio/química , Bloqueadores de los Canales de Calcio/uso terapéutico , Canales de Calcio/metabolismo , Humanos , Estructura Molecular , Canal de Sodio Activado por Voltaje NAV1.7 , Canal de Sodio Activado por Voltaje NAV1.8 , Neuralgia/tratamiento farmacológico , Neuralgia/metabolismo , Dolor/metabolismo , Enfermedades del Sistema Nervioso Periférico/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Bloqueadores de los Canales de Sodio/química , Bloqueadores de los Canales de Sodio/uso terapéutico , Canales de Sodio/metabolismo
18.
FEBS Lett ; 583(9): 1493-8, 2009 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-19375531

RESUMEN

XAP2 is member of a protein family sharing the TPR protein interaction motif. It displays close homology to the immunophilins FKBP51 and FKBP52 that act via the Hsp90 folding machinery to regulate the glucocorticoid receptor (GR). We show that XAP2 inhibits GR by reducing its responsiveness to hormone in transcriptional activation. The effect of XAP2 on GR requires its interaction with Hsp90 through the TPR motif. The PPIase-like region turned out to be enzymatically inactive. Thus, PPIase activity is not essential for the action of XAP2 on GR, similarly to FKBP51 and FKBP52.


Asunto(s)
Péptidos y Proteínas de Señalización Intracelular/fisiología , Receptores de Glucocorticoides/antagonistas & inhibidores , Western Blotting , Línea Celular , Proteínas HSP90 de Choque Térmico/metabolismo , Humanos , Inmunoprecipitación , Péptidos y Proteínas de Señalización Intracelular/genética , Péptidos y Proteínas de Señalización Intracelular/aislamiento & purificación , Isomerasa de Peptidilprolil/metabolismo , Unión Proteica , Sirolimus/metabolismo , Transcripción Genética/fisiología
19.
Chemistry ; 10(19): 4685-93, 2004 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-15372652

RESUMEN

In the asymmetric hydrogenation of unfunctionalized olefins with cationic iridium-PHOX catalysts, the reaction kinetics and, as a consequence, catalyst activity and productivity depend heavily on the counterion. A strong decrease in the reaction rate is observed in the series [Al[OC(CF3)3]4]- >BArF- >[B(C6F5)4]- >PF6- >>BF4- >CF3SO3-. With the first two anions, high rates, turnover frequencies (TOF >5000 h(-1) at 4 degrees C), and turnover numbers (TONs) of 2000-5000 are routinely achieved. The hexafluorophosphate salt reacts with lower rates, although they are still respectable; however, this salt suffers from deactivation during the reaction and extreme water-sensitivity, especially at low catalyst loading. Triflate and tetrafluoroborate almost completely inhibit the catalyst. In contrast to the hexafluorophosphate salt, catalysts with [Al[OC(CF3)3]4]-, BArF-, and [B(C6F5)4]- as counterions do not lose activity during the reaction and remain active, even after all the substrate has been consumed. In addition they are much less sensitive to moisture and, in general, rigorous exclusion of water and oxygen is not necessary. A first-order rate dependence on the hydrogen pressure was determined for the BArF- and the PF6- salts. At low catalyst loading, the rate dependence on catalyst concentration was also first order. The rate dependence on the alkene concentration was strikingly different for the two salts. While the reaction rate observed for the BArF- salt slightly decreased with increasing alkene concentration (rate order -0.2), a rate order of approximately 1 was determined for the corresponding hexafluorophosphate at low alkene concentrations.

20.
Bioorg Chem ; 32(1): 13-25, 2004 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-14700559

RESUMEN

Metal-dependent pairing of nucleobases represents an alternative DNA base pairing scheme. Our first-generation copper(II)-mediated pyridine-2,6-dicarboxylate (Dipic) and pyridine (Py) metallo-base pair has a stability comparable to the natural base pairs dA:dT and dC:dG but does not have the selectivity of the Watson Crick base pairs. In order to increase the selectivity of base pair formation, a second-generation metallo-base pair was generated consisting of a pyridine-2,6-dicarboxamide (Dipam) and a pyridine (Py) nucleobase. This new metallo-base pair is more stable than the natural base pairs dA:dT and dC:dG and highly selective against mispairing. In addition, incorporation of multiple metallo-base pairs into DNA results in the formation of stable duplexes demonstrating that hydrogen bonding base pairs can efficiently be replaced by metal-dependent base pairs at multiple sites in DNA.


Asunto(s)
Cobre/química , ADN/química , Emparejamiento Base , Ligandos , Conformación de Ácido Nucleico , Nucleósidos/química , Compuestos Organometálicos/química , Compuestos Organofosforados/síntesis química , Compuestos Organofosforados/química , Ácidos Picolínicos/química , Piridinas/química , Temperatura
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