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1.
Eur J Clin Invest ; 53(7): e13976, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36841951

RESUMEN

BACKGROUND: The aim of this study was to assess heart failure (HF) treatment in patients with and without obesity in a large contemporary real-world Western European cohort. METHODS: Patients with a left ventricular ejection fraction (LVEF) <50% and available information on body mass index (BMI) were selected from the CHECK-HF registry. The CHECK-HF registry included chronic HF patients in the period between 2013 and 2016 in 34 Dutch outpatient clinics. Patients were divided into BMI categories. Differences in HF medical treatment were analysed, and multivariable logistic regression analysis (dichotomized as BMI <30 kg/m2 and ≥30 kg/m2 ) was performed. RESULTS: Seven thousand six hundred seventy-one patients were included, 1284 (16.7%) had a BMI ≥30 kg/m2 , and 618 (8.1%) had a BMI ≥35 kg/m2 . Median BMI was 26.4 kg/m2 . Patients with obesity were younger and had a higher rate of comorbidities such as diabetes mellitus, hypertension and obstructive sleep apnoea (OSAS). Prescription rates of guideline-directed medical therapy (GDMT) increased significantly with BMI. The differences were most pronounced for mineralocorticoid receptor antagonists (MRAs) and diuretics. Patients with obesity more often received the guideline-recommended target dose. In multivariable logistic regression, obesity was significantly associated with a higher likelihood of receiving ≥100% of the guideline-recommended target dose of beta-blockers (OR 1.34, 95% CI 1.10-1.62), renin-angiotensin system (RAS)-inhibitors (OR 1.34, 95% CI 1.15-1.57) and MRAs (OR 1.40, 95% CI 1.04-1.87). CONCLUSIONS: Guideline-recommended HF drugs are more frequently prescribed and at a higher dose in patients with obesity as compared to HF patients without obesity.


Asunto(s)
Insuficiencia Cardíaca , Función Ventricular Izquierda , Humanos , Volumen Sistólico , Resultado del Tratamiento , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/epidemiología , Antagonistas Adrenérgicos beta/uso terapéutico , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Obesidad/complicaciones , Obesidad/epidemiología , Obesidad/tratamiento farmacológico , Antagonistas de Receptores de Angiotensina/uso terapéutico
2.
J Cardiothorac Vasc Anesth ; 37(9): 1601-1605, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37173171

RESUMEN

OBJECTIVES: This study aimed to describe the outcome of Jehovah's Witnesses (JWs) undergoing cardiac surgery at the authors' center. DESIGN: A single-center retrospective cohort study. SETTING: At a cardiovascular center with a tertiary intensive care unit (ICU) and specific experience with cardiac surgery in JWs. The institutional protocol describing all perioperative care in JWs has been applied for 21 years. PARTICIPANTS: All JWs undergoing cardiac surgery in the Amphia Hospital from January 1, 2001 to January 31, 2022. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study cohort comprised 329 JWs undergoing cardiac surgery. Twenty-three patients (6.8%) were treated preoperatively for anemia. The mean European System for Cardiac Operative Risk Evaluation score was 5.1 (range 0-18). Coronary artery bypass grafting (53.2%) was performed most frequently, followed by aortic valve replacement (13.4%). Mean preoperative hemoglobin levels were 14.5 g/dL (range 9.8-18.5 g/dL), dropping to 11.6 g/dL (range 6.6-15.6 g/dL) at hospital discharge. Mean blood loss was 439 ± 349 mL in the first 12 hours postsurgery. Maximum mean postoperative troponin levels were 431 ± 424 ng/L. Resternotomy and postoperative myocardial infarction occurred in 3.6% and 4.2% of patients, respectively. On average, patients had an ICU stay of 1.4 ± 1.8 days and a hospital stay of 6.8 ± 4.2 days. Hospital mortality was 0.6% and was related to cardiac failure. CONCLUSIONS: This study demonstrated that cardiac surgery in JWs is safe when adhering to a strict perioperative patient blood management protocol.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Testigos de Jehová , Humanos , Estudios Retrospectivos , Transfusión Sanguínea , Procedimientos Quirúrgicos Cardíacos/efectos adversos , Procedimientos Quirúrgicos Cardíacos/métodos , Puente de Arteria Coronaria
3.
Proc Natl Acad Sci U S A ; 116(38): 19136-19144, 2019 09 17.
Artículo en Inglés | MEDLINE | ID: mdl-31488709

RESUMEN

Zika virus (ZIKV) is an arthropod-borne flavivirus predominantly transmitted by Aedes aegypti mosquitoes and poses a global human health threat. All flaviviruses, including those that exclusively replicate in mosquitoes, produce a highly abundant, noncoding subgenomic flavivirus RNA (sfRNA) in infected cells, which implies an important function of sfRNA during mosquito infection. Currently, the role of sfRNA in flavivirus transmission by mosquitoes is not well understood. Here, we demonstrate that an sfRNA-deficient ZIKV (ZIKVΔSF1) replicates similar to wild-type ZIKV in mosquito cell culture but is severely attenuated in transmission by Ae. aegypti after an infectious blood meal, with 5% saliva-positive mosquitoes for ZIKVΔSF1 vs. 31% for ZIKV. Furthermore, viral titers in the mosquito saliva were lower for ZIKVΔSF1 as compared to ZIKV. Comparison of mosquito infection via infectious blood meals and intrathoracic injections showed that sfRNA is important for ZIKV to overcome the mosquito midgut barrier and to promote virus accumulation in the saliva. Next-generation sequencing of infected mosquitoes showed that viral small-interfering RNAs were elevated upon ZIKVΔSF1 as compared to ZIKV infection. RNA-affinity purification followed by mass spectrometry analysis uncovered that sfRNA specifically interacts with a specific set of Ae. aegypti proteins that are normally associated with RNA turnover and protein translation. The DEAD/H-box helicase ME31B showed the highest affinity for sfRNA and displayed antiviral activity against ZIKV in Ae. aegypti cells. Based on these results, we present a mechanistic model in which sfRNA sequesters ME31B to promote flavivirus replication and virion production to facilitate transmission by mosquitoes.


Asunto(s)
Aedes/virología , ARN Helicasas DEAD-box/metabolismo , Proteínas de Insectos/metabolismo , Mosquitos Vectores/virología , ARN Viral/genética , Infección por el Virus Zika/transmisión , Virus Zika/genética , Aedes/inmunología , Animales , Chlorocebus aethiops , ARN Helicasas DEAD-box/genética , Tracto Gastrointestinal/virología , Genoma Viral , Proteínas de Insectos/genética , Glándulas Salivales/virología , Replicación Viral , Virus Zika/inmunología , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología
4.
J Clin Immunol ; 41(6): 1219-1228, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33779897

RESUMEN

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening immune dysregulation syndrome characterized by uncontrolled immune cell activation. Timely diagnosis is important, since early treatment can improve survival rates. However, completing all assessments needed to reach ≥5 positive criteria out of the 8 HLH-2004 criteria can be time consuming and may delay timely initiation of treatment. Hence, we applied a data-driven approach to identify a minimal parameter set for early decision-making towards the initiation of HLH-specific treatment. We retrospectively evaluated 165 patients from five Dutch tertiary hospitals with suspected HLH. Sixteen pHLH (median age 0.5 years) and 70 sHLH patients (median age 8.7 years) were identified using the HLH-2004 criteria. Clustering analysis and multi-receiver operator characteristics were used to identify parameters distinctive of HLH. The presence of either increased ferritin, cytopenia in ≥2 lineages, or splenomegaly distinguished HLH from non-HLH cases with a negative predictive value of 100%. A minimal parameter set consisting of 2 major criteria (phagocytosis and splenomegaly) and 3 minor criteria (cytopenia, increased ferritin, and increased triglycerides/low fibrinogen) predicted HLH with 95% (88-99) sensitivity and 94% (86-98) specificity. This finding was replicated in an independent retrospective validation cohort of 109 US patients (n = 109). By dividing a subset of the HLH-2004 criteria into major and minor criteria, this strategy uses the evaluation of less than 5 criteria to quickly identify patients with HLH. When confirmed in a prospective setting, this approach could be of value for timely diagnosis and treatment of HLH.


Asunto(s)
Linfohistiocitosis Hemofagocítica/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Línea Celular Tumoral , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Células K562 , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
5.
J Clin Immunol ; 41(2): 382-392, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33206257

RESUMEN

BACKGROUND: Patients with an IgG subclass deficiency (IgSD) ± specific polysaccharide antibody deficiency (SPAD) often present with recurrent infections. Previous retrospective studies have shown that prophylactic antibiotics (PA) and immunoglobulin replacement therapy (IRT) can both be effective in preventing these infections; however, this has not been confirmed in a prospective study. OBJECTIVE: To compare the efficacy of PA and IRT in a randomized crossover trial. METHODS: A total of 64 patients (55 adults and 9 children) were randomized (2:2) between two treatment arms. Treatment arm A began with 12 months of PA, and treatment arm B began with 12 months of IRT. After a 3-month bridging period with cotrimoxazole, the treatment was switched to 12 months of IRT and PA, respectively. The efficacy (measured by the incidence of infections) and proportion of related adverse events in the two arms were compared. RESULTS: The overall efficacy of the two regimens did not differ (p = 0.58, two-sided Wilcoxon signed-rank test). A smaller proportion of patients suffered a related adverse event while using PA (26.8% vs. 60.3%, p < 0.0003, chi-squared test). Patients with persistent infections while using PA suffered fewer infections per year after switching to IRT (2.63 vs. 0.64, p < 0.01). CONCLUSION: We found comparable efficacy of IRT and PA in patients with IgSD ± SPAD. Patients with persistent infections during treatment with PA had less infections after switching to IRT. CLINICAL IMPLICATION: Given the costs and associated side-effects of IRT, it should be reserved for patients with persistent infections despite treatment with PA.


Asunto(s)
Profilaxis Antibiótica/métodos , Inmunoglobulina G/inmunología , Síndromes de Inmunodeficiencia/inmunología , Enfermedades de Inmunodeficiencia Primaria/inmunología , Enfermedades de Inmunodeficiencia Primaria/terapia , Niño , Femenino , Humanos , Deficiencia de IgG/inmunología , Masculino , Persona de Mediana Edad , Infección Persistente/inmunología
6.
Mol Pharm ; 18(10): 3820-3831, 2021 10 04.
Artículo en Inglés | MEDLINE | ID: mdl-34449222

RESUMEN

Telomerase represents an attractive target in oncology as it is expressed in cancer but not in normal tissues. The oligonucleotide inhibitors of telomerase represent a promising anticancer strategy, although poor cellular uptake can restrict their efficacy. In this study, gold nanoparticles (AuNPs) were used to enhance oligonucleotide uptake. "match" oligonucleotides complementary to the telomerase RNA template subunit (hTR) and "scramble" (control) oligonucleotides were conjugated to diethylenetriamine pentaacetate (DTPA) for 111In-labeling. AuNPs (15.5 nm) were decorated with a monofunctional layer of oligonucleotides (ON-AuNP) or a multifunctional layer of oligonucleotides, PEG(polethylene glycol)800-SH (to reduce AuNP aggregation) and the cell-penetrating peptide Tat (ON-AuNP-Tat). Match-AuNP enhanced the cellular uptake of radiolabeled oligonucleotides while retaining the ability to inhibit telomerase activity. The addition of Tat to AuNPs increased nuclear localization. 111In-Match-AuNP-Tat induced DNA double-strand breaks and caused a dose-dependent reduction in clonogenic survival of telomerase-positive cells but not telomerase-negative cells. hTR inhibition has been reported to sensitize cancer cells to ionizing radiation, and 111In-Match-AuNP-Tat therefore holds promise as a vector for delivery of radionuclides into cancer cells while simultaneously sensitizing them to the effects of the emitted radiation.


Asunto(s)
Sistema de Administración de Fármacos con Nanopartículas/farmacología , Oligonucleótidos/farmacología , Telomerasa/antagonistas & inhibidores , Línea Celular Tumoral , Oro , Humanos , Nanopartículas del Metal , Microscopía Confocal , Microscopía Electrónica de Transmisión , Sistema de Administración de Fármacos con Nanopartículas/administración & dosificación , Oligonucleótidos/administración & dosificación
7.
Cardiology ; 146(6): 713-719, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34148041

RESUMEN

OBJECTIVES: The aim of this study was to characterize the safety and efficiency of a strategy employing the limit of detection (LoD) of high-sensitivity troponin T (hs-TnT) as a gatekeeper for coronary computed tomography angiography (CCTA) in suspected acute coronary syndrome (ACS) patients in the emergency department (ED). METHODS: We included suspected ACS patients who underwent CCTA and were evaluated with hs-TnT. Patients were categorized as below the LoD and at or above the LoD. The primary outcome was 30-day major adverse cardiac events (MACEs), defined as all-cause mortality, ACS, or coronary revascularization. RESULTS: The study population consisted of 177 patients (mean age 55 ± 10 years, 50.3% women), and 16 (9.0%) patients reached the primary outcome. None of the patients died, while 13 had an adjudicated diagnosis of ACS, and 3 underwent elective coronary revascularization. There were 77 patients (44%) with an hs-TnT value below the LoD (MACEs; n = 1 [1.3%]) and 100 (56%) with at or above the LoD levels (MACEs; n = 15 [15%]). None of 67 patients with an hs-TnT value below the LoD and <50% stenosis on CCTA experienced MACEs. Out of the 10 patients with an hs-TnT value below the LoD and ≥50% stenosis on CCTA, 1 patient underwent elective percutaneous coronary revascularization. In patients with an hs-TnT value at or above the LoD, 74 patients had <50% stenosis on CCTA, and 2 patients (3%) were diagnosed with myocardial infarction without obstructive coronary artery disease confirmed on invasive angiography. Thirteen (50%) patients with an hs-TnT value at or above the LoD and ≥50% stenosis on CCTA experienced MACEs (11 ACS and 2 elective percutaneous coronary revascularizations). CONCLUSION: Our findings support that implementing the LoD of hs-TnT as a gatekeeper may reduce the need for CCTA in suspected ACS patients in the ED.


Asunto(s)
Síndrome Coronario Agudo , Troponina T , Síndrome Coronario Agudo/diagnóstico por imagen , Anciano , Angiografía , Angiografía por Tomografía Computarizada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Troponina T/análisis
8.
J Neurosci ; 39(45): 8916-8928, 2019 11 06.
Artículo en Inglés | MEDLINE | ID: mdl-31541020

RESUMEN

Our perceptual experience of sound depends on the integration of multiple sensory and cognitive domains, however the networks subserving this integration are unclear. Connections linking different cortical domains have been described, but we do not know the extent to which connections also exist between multiple cortical domains and subcortical structures. Retrograde tracing in adult male rats (Rattus norvegicus) revealed that the inferior colliculus, the auditory midbrain, receives dense descending projections not only, as previously established, from the auditory cortex, but also from the visual, somatosensory, motor, and prefrontal cortices. While all these descending connections are bilateral, those from sensory areas show a more pronounced ipsilateral dominance than those from motor and prefrontal cortices. Injections of anterograde tracers into the cortical areas identified by retrograde tracing confirmed those findings and revealed cortical fibers terminating in all three subdivisions of the inferior colliculus. Immunolabeling showed that cortical terminals target both GABAergic inhibitory, and putative glutamatergic excitatory neurons. These findings demonstrate that auditory perception and behavior are served by a network that includes extensive descending connections to the midbrain from sensory, behavioral, and executive cortices.SIGNIFICANCE STATEMENT Making sense of what we hear depends not only on the analysis of sound, but also on information from other senses together with the brain's predictions about the properties and significance of the sound. Previous work suggested that this interplay between the senses and the predictions from higher cognitive centers occurs within the cerebral cortex. By tracing neural connections in rat, we show that the inferior colliculus, the subcortical, midbrain center for hearing, receives extensive connections from areas of the cerebral cortex concerned with vision, touch, movement, and cognitive function, in addition to areas representing hearing. These findings demonstrate that wide-ranging cortical feedback operates at an earlier stage of the hearing pathway than previously recognized.


Asunto(s)
Vías Auditivas/citología , Mesencéfalo/fisiología , Corteza Sensoriomotora/fisiología , Animales , Vías Auditivas/fisiología , Potenciales Evocados Auditivos del Tronco Encefálico , Masculino , Mesencéfalo/citología , Técnicas de Trazados de Vías Neuroanatómicas , Neuronas/clasificación , Neuronas/fisiología , Ratas , Corteza Sensoriomotora/citología
9.
J Neurosci ; 39(5): 876-887, 2019 01 30.
Artículo en Inglés | MEDLINE | ID: mdl-30530507

RESUMEN

Nitric oxide (NO) is a neurotransmitter synthesized in the brain by neuronal nitric oxide synthase (nNOS). Using immunohistochemistry and confocal imaging in the inferior colliculus (IC, auditory midbrain) of the guinea pig (Cavia porcellus, male and female), we show that nNOS occurs in two distinct cellular distributions. We confirm that, in the cortices of the IC, a subset of neurons show cytoplasmic labeling for nNOS, whereas in the central nucleus (ICc), such neurons are not present. However, we demonstrate that all neurons in the ICc do in fact express nNOS in the form of discrete puncta found at the cell membrane. Our multi-labeling studies reveal that nNOS puncta form multiprotein complexes with NMDA receptors, soluble guanylyl cyclase (sGC), and PSD95. These complexes are found apposed to glutamatergic terminals, which is indicative of synaptic function. Interestingly, these glutamatergic terminals express both vesicular glutamate transporters 1 and 2 denoting a specific source of brainstem inputs. With in vivo electrophysiological recordings of multiunit activity in the ICc, we found that local application of NMDA enhances sound-driven activity in a concentration-dependent and reversible fashion. This response is abolished by blockade of nNOS or sGC, indicating that the NMDA effect is mediated solely via the NO and cGMP signaling pathway. This discovery of a ubiquitous, but highly localized, expression of nNOS throughout the ICc and demonstration of the dramatic influence of the NMDA activated NO pathway on sound-driven neuronal activity imply a key role for NO signaling in auditory processing.SIGNIFICANCE STATEMENT We show that neuronal nitric oxide synthase (nNOS), the enzyme that synthesizes nitric oxide (NO), occurs as puncta in apparently all neurons in the central nucleus of the inferior colliculus (ICc) in the auditory midbrain. Punctate nNOS appears at glutamatergic synapses in a complex with glutamate NMDA receptors (NMDA-Rs), soluble guanylyl cyclase (sGC, the NO receptor), and PSD95 (a protein that anchors receptors and enzymes at the postsynaptic density). We show that NMDA-R modulation of sound-driven activity in the ICc is solely mediated by activation of nNOS and sGC. The presence of nNOS throughout this sensory nucleus argues for a major role of NO in hearing. Furthermore, this punctate form of nNOS expression may exist and have gone unnoticed in other brain regions.


Asunto(s)
Corteza Auditiva/fisiología , Mesencéfalo/fisiología , Óxido Nítrico Sintasa de Tipo I/fisiología , Receptores de N-Metil-D-Aspartato/fisiología , Transducción de Señal/fisiología , Animales , Percepción Auditiva/fisiología , GMP Cíclico/fisiología , Homólogo 4 de la Proteína Discs Large/fisiología , Femenino , Cobayas , Colículos Inferiores/citología , Colículos Inferiores/fisiología , Masculino , Óxido Nítrico/fisiología , Óxido Nítrico Sintasa de Tipo I/metabolismo , Guanilil Ciclasa Soluble/metabolismo , Sinapsis/fisiología , Proteínas de Transporte Vesicular de Glutamato/metabolismo
10.
Eur J Neurosci ; 51(9): 1881-1899, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32115781

RESUMEN

Neuronal nitric oxide synthase (nNOS) catalyses the production of the neurotransmitter nitric oxide. nNOS is expressed in the dorsal raphe nucleus (DRN), a source of ascending serotonergic projections. In this study, we examined the distribution nNOS and the function of nitric oxide in the DRN and adjacent median raphe nucleus (MRN) of the rat. We hypothesized that nNOS is differentially expressed across the raphe nuclei and that nitric oxide influences the firing activity of a subgroup of 5-HT neurons. Immunohistochemistry revealed that, nNOS is present in around 40% of 5-HT neurons, throughout the DRN and MRN, as well as in some non-5-HT neurons immediately adjacent to the DRN and MRN. The nitric oxide receptor, soluble guanylyl cyclase, was present in all 5-HT neurons examined in the DRN and MRN. In vitro extracellular electrophysiology revealed that application of the nitric oxide donor, diethylamine NONOate (30-300 µM) inhibited 60%-70% of putative 5-HT neurons, excited approximately 10% of putative 5-HT neurons and had no effect on the rest. The inhibitory response to nitric oxide was blocked by [1H-[1,2,4]oxadiazolo-[4, 3-a]quinoxalin-1-one (ODQ, 30 or 100 µM), indicating mediation by soluble guanylyl cyclase. Juxtacellular labelling revealed that nitric oxide inhibits firing in both putative 5-HT neurons which express nNOS and those which do not express nNOS. Our data are consistent with the notion that nitric oxide acts as both a trans-synaptic and autocrine signaller in 5-HT neurons in the DRN and MRN and that its effects are widespread and primarily inhibitory.


Asunto(s)
Óxido Nítrico , Serotonina , Animales , Núcleo Dorsal del Rafe , Núcleos del Rafe Mesencefálico , Neuronas , Ratas
11.
Eur J Neurosci ; 52(2): 2915-2930, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31891427

RESUMEN

The role of dopamine in regulating sleep-state transitions during, both natural sleep and under anaesthesia, is still unclear. Recording in vivo in the rat mPFC under urethane anaesthesia, we observed predominantly slow wave activity (SWA) of <1 Hz in the local field potential interrupted by occasional spontaneous transitions to a low-amplitude-fast (LAF) pattern of activity. During periods of SWA, transitions to LAF activity could be rapidly and consistently evoked by electrical stimulation of the ventral tegmental area (VTA). Spontaneous LAF activity, and that evoked by stimulation of the VTA, consisted of fast oscillations similar to those seen in the rapid eye movement (REM)-like sleep state. Spontaneous and VTA stimulation-evoked LAF activity occurred simultaneously along the dorsoventral extent of all mPFC subregions. Evoked LAF activity depended on VTA stimulation current and could be elicited using either regular (25-50 Hz) or burst stimulation patterns and was reproducible upon repeated stimulation. Simultaneous extracellular single-unit recordings showed that during SWA, presumed pyramidal cells fired phasically and almost exclusively on the Up state, while during both spontaneous and VTA-evoked LAF activity, they fired tonically. The transition to LAF activity evoked by VTA stimulation depended on dopamine D1 -like receptor activation as it was almost completely blocked by systemic administration of the D1 -like receptor antagonist SCH23390. Overall, our data demonstrate that activation of dopamine D1 -like receptors in the mPFC is important for regulating sleep-like state transitions.


Asunto(s)
Anestesia , Área Tegmental Ventral , Animales , Dopamina , Estimulación Eléctrica , Corteza Prefrontal , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1 , Sueño , Uretano/farmacología
12.
Artículo en Inglés | MEDLINE | ID: mdl-31964798

RESUMEN

Alphaviruses are arthropod-borne, positive-stranded RNA viruses capable of causing severe disease with high morbidity. Chikungunya virus (CHIKV) is an alphavirus that causes a febrile illness which can progress into chronic arthralgia. The current lack of vaccines and specific treatment for CHIKV infection underscores the need to develop new therapeutic interventions. To discover new antiviral agents, we performed a compound screen in cell culture-based infection models and identified two carbocyclic adenosine analogues, 6'-ß-fluoro-homoaristeromycin (FHA) and 6'-fluoro-homoneplanocin A (FHNA), that displayed potent activity against CHIKV and Semliki Forest virus (SFV) with 50% effective concentrations in the nanomolar range at nontoxic concentrations. The compounds, designed as inhibitors of the host enzyme S-adenosylhomocysteine (SAH) hydrolase, impeded postentry steps in CHIKV and SFV replication. Selection of FHNA-resistant mutants and reverse genetics studies demonstrated that the combination of mutations G230R and K299E in CHIKV nonstructural protein 1 (nsP1) conferred resistance to the compounds. Enzymatic assays with purified wild-type (wt) SFV nsP1 suggested that an oxidized (3'-keto) form, rather than FHNA itself, directly inhibited the MTase activity, while a mutant protein with the K231R and K299E substitutions was insensitive to the compound. Both wt nsP1 and the resistant mutant were equally sensitive to the inhibitory effect of SAH. Our combined data suggest that FHA and FHNA inhibit CHIKV and SFV replication by directly targeting the MTase activity of nsP1, rather than through an indirect effect on host SAH hydrolase. The high potency and selectivity of these novel alphavirus mRNA capping inhibitors warrant further preclinical investigation of these compounds.


Asunto(s)
Adenosina/análogos & derivados , Antivirales/farmacología , Virus Chikungunya/efectos de los fármacos , Virus Chikungunya/fisiología , Adenosina/farmacología , Animales , Virus Chikungunya/patogenicidad , Chlorocebus aethiops , Relación Dosis-Respuesta a Droga , Evaluación Preclínica de Medicamentos , Farmacorresistencia Viral/efectos de los fármacos , Farmacorresistencia Viral/genética , Guanosina Monofosfato/metabolismo , Mutación , Radioisótopos de Fósforo , Virus de los Bosques Semliki/efectos de los fármacos , Células Vero , Proteínas no Estructurales Virales/antagonistas & inhibidores , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/efectos de los fármacos
13.
Proc Natl Acad Sci U S A ; 114(27): 7013-7018, 2017 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-28630286

RESUMEN

Fluorophores with dynamic or controllable fluorescence emission have become essential tools for advanced imaging, such as superresolution imaging. These applications have driven the continuing development of photoactivatable or photoconvertible labels, including genetically encoded fluorescent proteins. These new probes work well but require the introduction of new labels that may interfere with the proper functioning of existing constructs and therefore require extensive functional characterization. In this work we show that the widely used red fluorescent protein mCherry can be brought to a purely chemically induced blue-fluorescent state by incubation with ß-mercaptoethanol (ßME). The molecules can be recovered to the red fluorescent state by washing out the ßME or through irradiation with violet light, with up to 80% total recovery. We show that this can be used to perform single-molecule localization microscopy (SMLM) on cells expressing mCherry, which renders this approach applicable to a very wide range of existing constructs. We performed a detailed investigation of the mechanism underlying these dynamics, using X-ray crystallography, NMR spectroscopy, and ab initio quantum-mechanical calculations. We find that the ßME-induced fluorescence quenching of mCherry occurs both via the direct addition of ßME to the chromophore and through ßME-mediated reduction of the chromophore. These results not only offer a strategy to expand SMLM imaging to a broad range of available biological models, but also present unique insights into the chemistry and functioning of a highly important class of fluorophores.


Asunto(s)
Colorantes Fluorescentes/química , Proteínas Luminiscentes/química , Microscopía Fluorescente/instrumentación , Animales , Células COS , Chlorocebus aethiops , Color , Cristalografía por Rayos X , Células HeLa , Humanos , Luz , Espectroscopía de Resonancia Magnética , Mercaptoetanol/química , Microscopía Fluorescente/métodos , Procesos Fotoquímicos , Teoría Cuántica , Sustancias Reductoras/química , Programas Informáticos , Rayos X , Proteína Fluorescente Roja
14.
J Neurol Neurosurg Psychiatry ; 90(12): 1331-1337, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31292200

RESUMEN

BACKGROUND: Funding and resources for low prevalent neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) are limited, and optimising their use is vital for efficient drug development. In this study, we review the design assumptions for pivotal ALS clinical trials with time-to-event endpoints and provide optimised settings for future trials. METHODS: We extracted design settings from 13 completed placebo-controlled trials. Optimal assumptions were estimated using parametric survival models in individual participant data (n=4991). Designs were compared in terms of sample size, trial duration, drug use and costs. RESULTS: Previous trials overestimated the hazard rate by 18.9% (95% CI 3.4% to 34.5%, p=0.021). The median expected HR was 0.56 (range 0.33-0.66). Additionally, we found evidence for an increasing mean hazard rate over time (Weibull shape parameter of 2.03, 95% CI 1.93 to 2.15, p<0.001), which affects the design and planning of future clinical trials. Incorporating accrual time and assuming an increasing hazard rate at the design stage reduced sample size by 33.2% (95% CI 27.9 to 39.4), trial duration by 17.4% (95% CI 11.6 to 23.3), drug use by 14.3% (95% CI 9.6 to 19.0) and follow-up costs by 21.2% (95% CI 15.6 to 26.8). CONCLUSIONS: Implementing distributional knowledge and incorporating accrual at the design stage could achieve large gains in the efficiency of ALS clinical trials with time-to-event endpoints. We provide an open-source platform that helps investigators to make more accurate sample size calculations and optimise the use of their available resources.


Asunto(s)
Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Ensayos Clínicos como Asunto/métodos , Determinación de Punto Final/métodos , Proyectos de Investigación , Adulto , Femenino , Humanos , Masculino , Calidad de Vida , Riluzol/uso terapéutico
15.
J Ind Microbiol Biotechnol ; 46(8): 1179-1190, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31187318

RESUMEN

Rhodobacter sphaeroides is a metabolically versatile bacterium capable of producing terpenes natively. Surprisingly, terpene biosynthesis in this species has always been investigated in complex media, with unknown compounds possibly acting as carbon and nitrogen sources. Here, a defined medium was adapted for R. sphaeroides dark heterotrophic growth, and was used to investigate the conversion of different organic substrates into the reporter terpene amorphadiene. The amorphadiene synthase was cloned in R. sphaeroides, allowing its biosynthesis via the native 2-methyl-D-erythritol-4-phosphate (MEP) pathway and, additionally, via a heterologous mevalonate one. The latter condition increased titers up to eightfold. Consequently, better yields and productivities to previously reported complex media cultivations were achieved. Productivity was further investigated under different cultivation conditions, including nitrogen and oxygen availability. This novel cultivation setup provided useful insight into the understanding of terpene biosynthesis in R. sphaeroides, allowing to better comprehend its dynamics and regulation during chemoheterotrophic cultivation.


Asunto(s)
Procesos Heterotróficos , Sesquiterpenos Policíclicos/metabolismo , Rhodobacter sphaeroides/metabolismo , Carbono/metabolismo , Eritritol/análogos & derivados , Eritritol/metabolismo , Nitrógeno/metabolismo , Rhodobacter sphaeroides/genética , Fosfatos de Azúcar/metabolismo
16.
Eur Radiol ; 28(5): 2169-2175, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29247351

RESUMEN

OBJECTIVE: To assess the image quality of coronary CT angiography (CCTA) for suspected acute coronary syndrome (ACS) outside office hours. METHODS: Patients with symptoms suggestive of an ACS underwent CCTA at the emergency department 24 hours, 7 days a week. A total of 118 patients, of whom 89 (75 %) presented during office hours (weekdays between 07:00 and 17:00) and 29 (25 %) outside office hours (weekdays between 17:00 and 07:00, weekends and holidays) underwent CCTA. Image quality was evaluated per coronary segment by two experienced readers and graded on an ordinal scale ranging from 1 to 3. RESULTS: There were no significant differences in acquisition parameters, beta-blocker administration or heart rate between patients presenting during office hours and outside office hours. The median quality score per patient was 30.5 [interquartile range 26.0-33.5] for patients presenting during office hours in comparison to 27.5 [19.75-32.0] for patients presenting outside office hours (p=0.043). The number of non-evaluable segments was lower for patients presenting during office hours (0 [0-1.0] vs. 1.0 [0-4.0], p=0.009). CONCLUSION: Image quality of CCTA outside office hours in the diagnosis of suspected ACS is diminished. KEY POINTS: • Quality scores were higher for coronary-CTA during office hours. • There were no differences in acquisition parameters. • There was a non-significant trend towards higher heart rates outside office hours. • Coronary-CTA on the ED requires state-of-the-art scanner technology and sufficiently trained staff. • Coronary-CTA on the ED needs preparation time and optimisation of the procedure.


Asunto(s)
Síndrome Coronario Agudo/diagnóstico , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Unidades de Cuidados Coronarios , Vasos Coronarios/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
17.
Acta Psychiatr Scand ; 138(4): 312-324, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29952088

RESUMEN

OBJECTIVE: Exposure to sexual assault is a significant risk factor to develop post-traumatic stress disorder (PTSD) in females. The early neurobiological changes leading to the development of PTSD remain understudied and unclear in this population. METHODS: Participants were 27 adult females recruited within a month following exposure to sexual assault (T1) and 20 age-matched non-exposed controls. Among the victims, 10 participants met (PTSD+) and 15 did not meet (PTSD-) DSM-IV criteria for PTSD 6 months post-trauma (T2). At both visits, hippocampal and amygdala volumes were extracted from magnetic resonance imaging scans, and indices of total diurnal cortisol changes were derived from individual areas under the curve relative to the ground (AUCg). Measures at T1 were compared between groups at T1, measures at T2 between groups at T2, and measures at T1 between groups at T2. RESULTS: At T1, victims had significantly smaller bilateral hippocampal volumes, but not AUCg, than controls. At T2, neither hippocampal volume nor AUCg significantly differed among the groups. However, the PTSD+ group had significantly smaller hippocampal volumes at T1 than the control group, but not compared to the PTSD- group. CONCLUSIONS: This study indicates that having smaller hippocampal volumes is a risk factor to develop PTSD in females exposed to sexual assault.


Asunto(s)
Hipocampo/patología , Delitos Sexuales , Trastornos por Estrés Postraumático/patología , Adolescente , Adulto , Amígdala del Cerebelo/diagnóstico por imagen , Amígdala del Cerebelo/patología , Femenino , Estudios de Seguimiento , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Factores de Riesgo , Trastornos por Estrés Postraumático/diagnóstico por imagen , Trastornos por Estrés Postraumático/metabolismo , Trastornos por Estrés Postraumático/fisiopatología , Adulto Joven
18.
Eur Arch Otorhinolaryngol ; 275(7): 1767-1773, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29721614

RESUMEN

PURPOSE: Acute edema of the head and neck region may lead to life-threatening dyspnea and require quick and targeted treatment. They can be subdivided in bradykinin- and histamine-mediated swellings, which require treatment with different classes of pharmaceuticals. Clinical pathways for differential diagnoses do not exist so far, although it is known that early treatment is decisive for faster symptom relief and reduced expression of the swellings. Aim of the study was the creation of a clinical algorithm for identification of bradykinin-mediated angioedema. METHODS: 188 patients that presented to our outpatient department between 2010 and 2016 with an acute, non-inflammatory swelling of the head and neck region were included in our retrospective study. All available anamnestic and clinical parameters were obtained from patient files. Parameters showing significant differences between the two groups were included in our score. Utilization of the Youden's index allowed determination of an optimal cut-off value. RESULTS: 76 patients could be assigned to the histamine and 112 patients to bradykinin group. The following parameters were included in our score: age, dyspnea, itching or erythema, glucocorticoid response and intake of ACEi/AT-II blockers. The cut-off value is set at three points. The proposed score yielded a sensitivity for identification of bradykinin-mediated angioedema of 96%, a specificity of 84%, a positive predictive value of 91% and a negative predictive value of 93%. CONCLUSIONS: Utilization of the proposed score allows quick and reliable assignment of patients to the correct subgroup and thereby reduces time for treatment.


Asunto(s)
Angioedema/diagnóstico , Angioedema/etiología , Bradiquinina , Cabeza , Histamina , Cuello , Adulto , Anciano , Anciano de 80 o más Años , Angioedema/terapia , Diagnóstico Diferencial , Femenino , Glucocorticoides/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
19.
J Fish Biol ; 92(2): 420-437, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29235096

RESUMEN

Stable isotope ratios of C and N in the bone tissue of three different skeletal elements (angular, cleithrum and vertebra) of three fish species from different evolutionary lineages (Clupeiformes, Atheriniformes and Notothenioidei) were determined before (δ13 Cbulk and δ15 Nbulk ) and after demineralization and delipidation (δ13 Cdml and δ15 Ndml ). One of the species had cellular bone and the other two had acellular bone. Results revealed that δ15 N and δ13 C values from different skeletal elements were interchangeable in species with acellular bone, but caution was needed in species with cellular bone, as δ15 N values varied among skeletal elements. Furthermore, δ15 Nbulk values were significantly lower than δ15 Ndml values in the three species, thus suggesting that they are not comparable. This difference is probably because δ15 Nbulk refers to total bone protein and δ15 Ndml to collagen only.


Asunto(s)
Huesos/química , Peces , Animales , Técnica de Desmineralización de Huesos , Isótopos de Carbono/análisis , Lípidos/aislamiento & purificación , Isótopos de Nitrógeno/análisis , Perciformes , Alimentos Marinos
20.
Appl Microbiol Biotechnol ; 101(12): 5175-5188, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28321487

RESUMEN

Benzene is an aromatic compound and harmful for the environment. Biodegradation of benzene can reduce the toxicological risk after accidental or controlled release of this chemical in the environment. In this study, we further characterized an anaerobic continuous biofilm culture grown for more than 14 years on benzene with nitrate as electron acceptor. We determined steady state degradation rates, microbial community composition dynamics in the biofilm, and the initial anaerobic benzene degradation reactions. Benzene was degraded at a rate of 0.15 µmol/mg protein/day and a first-order rate constant of 3.04/day which was fourfold higher than rates reported previously. Bacteria belonging to the Peptococcaceae were found to play an important role in this anaerobic benzene-degrading biofilm culture, but also members of the Anaerolineaceae were predicted to be involved in benzene degradation or benzene metabolite degradation based on Illumina MiSeq analysis of 16S ribosomal RNA genes. Biomass retention in the reactor using a filtration finger resulted in reduction of benzene degradation capacity. Detection of the benzene carboxylase encoding gene, abcA, and benzoic acid in the culture vessel indicated that benzene degradation proceeds through an initial carboxylation step.


Asunto(s)
Bacterias/metabolismo , Benceno/metabolismo , Biodegradación Ambiental , Biopelículas/crecimiento & desarrollo , Desnitrificación , Consorcios Microbianos/fisiología , Anaerobiosis , Bacterias/clasificación , Bacterias/efectos de los fármacos , Bacterias/genética , Benceno/farmacología , Ácido Benzoico/análisis , Biopelículas/efectos de los fármacos , Medios de Cultivo/química , Consorcios Microbianos/efectos de los fármacos , Consorcios Microbianos/genética , Nitratos/metabolismo , Peptococcaceae/clasificación , Peptococcaceae/genética , Peptococcaceae/aislamiento & purificación , Peptococcaceae/metabolismo , ARN Ribosómico 16S/genética
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