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2.
Int J Environ Health Res ; : 1-14, 2024 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-38245844

RESUMEN

The association of air pollution and greenspace with respiratory pathogen acquisition and respiratory health was investigated in a community-based birth-cohort of 158 Australian children. Weekly nasal swabs and daily symptom-diaries were collected for 2-years, with annual reviews from ages 3-7-years. Annual exposure to fine-particulate-matter (PM2.5), nitrogen-dioxide (NO2), and normalised-difference-vegetation-index (NDVI) was estimated for pregnancy and the first 2-years-of-life. We examined rhinovirus, any respiratory virus, Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae detections in the first 3-months-of-life, age at initial pathogen detection, wheezing in the first 2-years, and asthma at ages 5-7-years. Our findings suggest that higher NDVI was associated with fewer viral and M. catarrhalis detections in the first 3-months, while increased PM2.5 and NO2 were linked to earlier symptomatic rhinovirus and H. influenzae detections, respectively. However, no associations were observed with wheezing or asthma. Early-life exposure to air pollution and greenspace may influence early-life respiratory pathogen acquisition and illness. .

3.
Pediatr Pulmonol ; 58(12): 3428-3436, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37671813

RESUMEN

OBJECTIVE: Airway interactions between viruses, especially rhinoviruses, and potentially pathogenic bacteria (PPB; Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis) in early infancy may increase the risk of subsequent wheezing and asthma. We evaluated the association between rhinovirus and PPB in the first 3 months of life and wheezing episodes before age 2 years and asthma at age 5-7 years. METHODS: An Australian community-based birth cohort of healthy children involved parents collecting nasal swabs weekly and completing symptom diaries daily until age 2 years. In a follow-up subset, asthma diagnosis was assessed annually until age 7 years. Swabs were analyzed by real-time polymerase chain reaction assays. Children were included if they returned symptom diaries beyond age 3 months (wheeze) or were reviewed at age 5-7 years (asthma). RESULTS: 1440 swabs were returned by 146 children in the first 3 months of life. Wheeze and asthma outcomes were recorded for 146 and 84 children, respectively. Each additional week of rhinovirus detection increased the incidence of wheezing before age 2 years by 1.16 times (95% confidence interval [CI]: 0.99-1.35). There were no significant associations between bacteria and wheeze. Each additional week with H. influenzae increased the odds of asthma at age 5-7 years by 135% (odds ratio: 2.35, 95% CI: 0.99-5.58). No significant interaction was observed between rhinovirus and PPB for wheezing or asthma. CONCLUSION: Early life rhinovirus infection was associated with wheezing before age 2 years and H. influenzae with asthma by age 5-7 years. Microbes may play an etiologic role in wheezing and asthma, warranting further study.


Asunto(s)
Asma , Rhinovirus , Niño , Humanos , Lactante , Preescolar , Ruidos Respiratorios/etiología , Australia/epidemiología , Asma/diagnóstico , Bacterias , Haemophilus influenzae
4.
J Clin Virol ; 155: 105249, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35939878

RESUMEN

BACKGROUND: Cross-sectional studies report negative associations between rhinovirus and other RNA respiratory viruses. However, longitudinal studies with frequent, serial sampling are needed to identify the directionality of this relationship and its nature. OBJECTIVE: To investigate the association between rhinovirus and other RNA respiratory viruses detected 1-week apart. METHODS: The Observational Research in Childhood Infectious Diseases cohort study was conducted in Brisbane, Australia (2010-2014). Parents collected nasal swabs weekly from birth until age 2-years. Swabs were analysed by real-time polymerase chain reaction. The association between new rhinovirus detections and five other RNA viruses (influenza, respiratory syncytial virus, parainfluenza viruses, seasonal human coronaviruses, and human metapneumovirus) in paired swabs 1-week apart were investigated. RESULTS: Overall, 157 children provided 8,101 swabs, from which 4,672 paired swabs 1-week apart were analysed. New rhinovirus detections were negatively associated with new pooled RNA respiratory virus detections 1-week later (adjusted odds ratio (aOR) 0.48; 95% confidence interval (CI): 0.13-0.83), as were pooled RNA virus detections with new rhinovirus detections the following week (aOR 0.34; 95%CI: 0.09-0.60). At the individual species level, rhinovirus had the strongest negative association with new seasonal human coronavirus detections in the subsequent week (aOR 0.34; 95%CI: 0.120.95) and respiratory syncytial virus had the strongest negative association with rhinovirus 1-week later (aOR 0.21; 95%CI: 0.050.88). CONCLUSION: A strong, negative bidirectional association was observed between rhinovirus and other RNA viruses in a longitudinal study of a community-based cohort of young Australian children. This suggests within-host interference between RNA respiratory viruses.


Asunto(s)
Infecciones por Enterovirus , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Virus , Australia/epidemiología , Cohorte de Nacimiento , Niño , Preescolar , Estudios de Cohortes , Estudios Transversales , Humanos , Lactante , Estudios Longitudinales , Estudios Prospectivos , ARN , Infecciones del Sistema Respiratorio/epidemiología , Rhinovirus/genética
5.
Pediatr Res ; 92(5): 1381-1390, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35136199

RESUMEN

BACKGROUND: Healthcare delivery is reliant on a functional central venous access device (CVAD), but the knowledge surrounding the burden of pediatric CVAD-associated harm is limited. METHODS: A prospective cohort study at a tertiary-referral pediatric hospital in Australia. Children <18 years undergoing insertion of a CVAD were screened from the operating theatre and intensive care unit records, then assessed bi-weekly for up to 3 months. Outcomes were CVAD failure and complications, and associated healthcare costs (cost of complications). RESULTS: 163 patients with 200 CVADs were recruited and followed for 6993 catheter days, with peripherally inserted central catheters most common (n = 119; 60%). CVAD failure occurred in 20% of devices (n = 30; 95% CI: 15-26), at an incidence rate (IR) of 5.72 per 1000 catheter days (95% CI: 4.09-7.78). CVAD complications were evident in 43% of all CVADs (n = 86; 95% CI: 36-50), at a rate of 12.29 per 1000 catheter days (95% CI: 9.84-15.16). CVAD failure costs were A$826 per episode, and A$165,372 per 1000 CVADs. Comparisons between current and recommended practice revealed inconsistent use of ultrasound guidance for insertion, sub-optimal tip-positioning, and appropriate device selection. CONCLUSIONS: CVAD complications and failures represent substantial burdens to children and healthcare. Future efforts need to focus on the inconsistent use of best practices. IMPACT: Current surveillance of central venous access device (CVAD) performance is likely under-estimating actual burden on pediatric patients and the healthcare system. CVAD failure due to complication was evident in 20% of CVADs. Costs associated with CVAD complications average at $2327 (AUD, 2020) per episode. Further investment in key diverse practice areas, including new CVAD types, CVAD pathology-based occlusion and dislodgment strategies, the appropriate use of device types, and tip-positioning technologies, will likely lead to extensive benefit.


Asunto(s)
Cateterismo Venoso Central , Cateterismo Periférico , Catéteres Venosos Centrales , Niño , Humanos , Catéteres Venosos Centrales/efectos adversos , Estudios Prospectivos , Incidencia , Australia/epidemiología , Cateterismo Venoso Central/efectos adversos
6.
Pediatr Pulmonol ; 56(12): 3942-3951, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34549896

RESUMEN

OBJECTIVE: To determine the potential longer-term effects of maternal antenatal respiratory syncytial virus (RSV) vaccination, we examined the association between cord-blood RSV-neutralizing antibodies (RSV-NA) and RSV infections in the first 2 years of life, RSV-NA at 3 years, and respiratory health to age 5 years. METHODS: Two community-based Australian birth cohorts were combined. For children with at least one atopic parent, paired serum RSV-NA levels were compared in cord blood and at age 3 years. Weekly nasal swabs were collected in one cohort and during acute respiratory infections (ARI) in the other. Wheeze history up to age 5 years and physician-diagnosed asthma at 5 years was collected by parent report. RESULTS: In 264 children, each log10 increase of cord-blood RSV-NA level was associated with 37% decreased risk (adjusted incidence-rate-ratio [aIRR] 0.63; 95% confidence interval [CI]: 0.40-1.01) of RSV-ARI and 49% decreased risk (aIRR 0.51; 95% CI: 0.25-1.02) of RSV acute lower respiratory infections (ALRI) at 12-24 months of age. However, higher cord-blood RSV-NA was associated with increased risk of all-cause ALRI (aIRR 1.29; 95% CI: 0.99-1.69), wheeze-associated ALRI (aIRR 1.75; 95% CI: 1.08-2.82), and severe ALRI (aIRR 2.76; 95% CI: 1.63-4.70) at age 6-<12 months. Cord-blood RSV-NA was not associated with RSV-ARI in the first 6-months, RSV-NA levels at 3 years, or wheeze or asthma at 5 years. CONCLUSIONS: Higher levels of cord-blood RSV-NA did not protect against RSV infections during the first 6-months-of-life, time-to-first RSV-ARI, or wheeze or asthma in the first 5 years of life. Additional strategies to control RSV-related illness in childhood are needed.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Australia/epidemiología , Cohorte de Nacimiento , Niño , Preescolar , Femenino , Sangre Fetal , Hospitalización , Humanos , Lactante , Embarazo , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones del Sistema Respiratorio/epidemiología
7.
Eur J Pediatr ; 180(7): 2125-2135, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33634335

RESUMEN

Respiratory syncytial virus (RSV) is the most common virus identified in children hospitalised with acute respiratory infections. However, less is known about RSV in community settings. This report describes RSV epidemiology in the community, including acute illness episodes, healthcare burden, and risk factors in Australian children during the first 2-years of life. A community-based, birth cohort from Brisbane, Australia, followed children until their second birthday. Parents completed daily respiratory symptom and illness-burden diaries. Weekly parent-collected nasal swabs were analysed for RSV by real-time polymerase chain reaction assays. Serum RSV-neutralising antibodies were assayed at age 3 years. Overall, 158 children provided 11,216 swabs, of which 104 were RSV-positive (85 incident episodes). RSV incidence in the first 2 years of life was 0.46 (95% CI = 0.37-0.58) episodes per child-year. Incidence increased with age and formal childcare attendance and was highest in autumn. Of 82 episodes linked with symptom data, 60 (73.2%) were symptomatic, 28 (34.1%) received community-based medical care, and 2 (2.4%) led to hospitalisation. Viral load was higher in symptomatic than asymptomatic infections. In 72 children, RSV-specific antibody seroprevalence was 94.4% at age 3 years.Conclusion: RSV incidence increased after age 6-months with approximately three-quarters of infections symptomatic and most infections treated in the community. What is known •RSV is a major cause of hospitalisation for acute lower respiratory infections in infants and young children, especially in the first 6 months of life. •However, limited data exist on the overall burden in young children at the community level. What is new •RSV incidence in the community increases after age 6 months, and by 3 years, most children have been infected. •About one-quarter of RSV infections were asymptomatic in children aged < 2 years, and approximately 60% of children with RSV-related symptoms had a healthcare contact of any kind with most managed within the community.


Asunto(s)
Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Australia/epidemiología , Niño , Preescolar , Hospitalización , Humanos , Incidencia , Lactante , Infecciones por Virus Sincitial Respiratorio/epidemiología , Factores de Riesgo , Estudios Seroepidemiológicos
8.
Aging Clin Exp Res ; 31(11): 1685-1688, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31359370

RESUMEN

Frailty has been indicated as a way for capturing biological aging of the individual and Frailty Index (FI) may serve for this purpose. This study designed the FI in a cohort of centenarians, their offspring and control subjects sex- and age-matched with offspring. The FI mean value was 0.47 (SD 0.13) in centenarians, 0.15 (SD 0.12) in their offspring, and 0.22 (SD 0.14) in controls (p < 0.001). The difference between offspring and controls was statistically significant (p = 0.003). The correlation between FI and age was significant in offspring (r = 0.46, p < 0.001), close to significance in controls (r = 0.25, p = 0.08) and not significant in centenarians. Our study confirms that FI is a marker of biological age useful to discriminate different degrees of frailty even at extremely advanced age.


Asunto(s)
Anciano Frágil , Fragilidad/fisiopatología , Evaluación Geriátrica/métodos , Hijos Adultos , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Estudios de Casos y Controles , Estudios de Cohortes , Estudios Transversales , Femenino , Fragilidad/diagnóstico , Humanos , Masculino , Persona de Mediana Edad
9.
Mech Ageing Dev ; 178: 41-45, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30658061

RESUMEN

INTRODUCTION: The genetic background plays a role on longevity. The distribution of the apolipoprotein E gene (APOE) variants (ε2, ε3, ε4) may differ across age groups, especially in the oldest old and despite geographical and ethnic specificities. Since the ε4 variant is associated with Alzheimer's disease (AD), it might represent an opportunity for exploring the relationship of APOE with physiological and pathological aging. AIM: To explore the role played by APOE genotype/alleles on physiological and pathological brain aging. MATERIALS AND METHODS: The study was conducted in a cohort of centenarians (n = 106), and two cohorts of octogenarians (without cognitive decline, n = 351 controls; and with AD, n = 294). RESULTS: No significant differences in genotype/allele distributions were observed comparing controls to centenarians. The prevalence of ε2/ε3, ε3/ε3, ε3/ε4 and ε4/ε4 genotypes were significantly different in centenarians compared to AD. The prevalence of ε2 and ε3 alleles were significantly higher in centenarians, whereas the ε4 was less frequent. The ε4 allele was positively associated with AD, whereas a negative association was found for ε2 and ε3 alleles. CONCLUSIONS: Our study indicates that ε4 allele is strongly associated with AD. APOE significantly affects AD risk, but apparently not longevity.


Asunto(s)
Envejecimiento/genética , Apolipoproteína E2/genética , Apolipoproteína E3/genética , Apolipoproteína E4/genética , Envejecimiento Saludable/genética , Anciano , Anciano de 80 o más Años , Alelos , Enfermedad de Alzheimer/sangre , Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/genética , Estudios de Cohortes , Femenino , Genotipo , Humanos , Modelos Logísticos , Longevidad/genética , Masculino , Polimorfismo Genético , Sistema de Registros/estadística & datos numéricos
10.
Neuron ; 101(3): 472-485.e7, 2019 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-30638745

RESUMEN

Minimal sets of transcription factors can directly reprogram somatic cells into neurons. However, epigenetic remodeling during neuronal reprogramming has not been well reconciled with transcriptional regulation. Here we show that NeuroD1 achieves direct neuronal conversion from mouse microglia both in vitro and in vivo. Exogenous NeuroD1 initially occupies closed chromatin regions associated with bivalent trimethylation of histone H3 at lysine 4 (H3K4me3) and H3K27me3 marks in microglia to induce neuronal gene expression. These regions are resolved to a monovalent H3K4me3 mark at later stages of reprogramming to establish the neuronal identity. Furthermore, the transcriptional repressors Scrt1 and Meis2 are induced as NeuroD1 target genes, resulting in a decrease in the expression of microglial genes. In parallel, the microglial epigenetic signature in promoter and enhancer regions is erased. These findings reveal NeuroD1 pioneering activity accompanied by global epigenetic remodeling for two sequential events: onset of neuronal property acquisition and loss of the microglial identity during reprogramming.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Reprogramación Celular , Epigénesis Genética , Microglía/citología , Neuronas/citología , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Células Cultivadas , Cuerpo Estriado/citología , Femenino , Células HEK293 , Código de Histonas , Histonas/química , Histonas/metabolismo , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos ICR , Microglía/metabolismo , Neuronas/metabolismo
11.
Age Ageing ; 47(6): 905-906, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30007289

RESUMEN

An 81-year-old woman was hospitalised for behavioural disorders that had been progressively emerging over a period of few weeks. The symptoms appeared to worsen over time. A diagnosis of vascular dementia, complicated by psychosis, was initially hypothesised. The inefficacy of the antipsychotic/benzodiazepine medications used, along with the presence of hypertension, hypokalaemia and metabolic alkalosis (resistant to pharmacological attempts of correction), as well as the hirsutism and the development of several infections, led us to consider Cushing's syndrome. Endocrinological analysis suggested ectopic adrenocorticotropic hormone (ACTH) secretion. Although endogenous Cushing's syndrome is rare in older people, it should always be considered among the differential diagnosis of behavioural disorders.


Asunto(s)
Síndrome de Cushing/complicaciones , Trastornos Mentales/etiología , Anciano de 80 o más Años , Antipsicóticos/uso terapéutico , Síndrome de Cushing/diagnóstico , Síndrome de Cushing/tratamiento farmacológico , Diagnóstico Diferencial , Inhibidores Enzimáticos/uso terapéutico , Resultado Fatal , Femenino , Humanos , Trastornos Mentales/diagnóstico , Trastornos Mentales/tratamiento farmacológico , Trastornos Mentales/psicología , Metirapona/uso terapéutico , Valor Predictivo de las Pruebas , Fumarato de Quetiapina/uso terapéutico , Factores de Riesgo , Resultado del Tratamiento
13.
Eur J Neurol ; 25(6): 805-810, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29377401

RESUMEN

BACKGROUND AND PURPOSE: Neuroinflammation plays a role in the aetiopathogenesis of Alzheimer's disease (AD). Triggering receptor expressed on myeloid cells 2 (TREM2), a cell surface receptor of the immunoglobulin superfamily, seems to have protective anti-inflammatory activity in AD. METHODS: Triggering receptor expressed on myeloid cells 2 expression was analysed in peripheral blood mononuclear cells from healthy subjects (CT) and from patients with either AD or mild cognitive impairment (MCI). MCI patients were re-evaluated at a 2-year follow-up to investigate their progression to AD (MCI-AD) or lack thereof (MCI-MCI). RESULTS: Triggering receptor expressed on myeloid cells 2 gene expression was higher in AD than CT patients, but was highest in MCI. At recruitment TREM2 levels were higher in MCI-AD than in MCI-MCI, and in MCI-AD were higher initially than at follow-up. TREM2 displayed a moderate degree of sensitivity and specificity for identifying MCI-AD in all MCI patients. Our data showed higher TREM2 levels in allele ε4 of apolipoprotein E (ApoE ε4) carriers than non-carriers in MCI and particularly in MCI-AD. CONCLUSIONS: These data seem to confirm the protective role of TREM2 in the pre-clinical stage of AD. Upregulation of TREM2 in MCI-AD could be a mechanism to counteract the activation of neuroinflammatory processes. It is possible that TREM2 and ApoE ε4 interact synergistically in the pre-clinical stage of AD. Therefore, TREM2 may be useful as an early peripheral biomarker for the development of AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Disfunción Cognitiva/metabolismo , Leucocitos Mononucleares/metabolismo , Glicoproteínas de Membrana/metabolismo , Receptores Inmunológicos/metabolismo , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/etiología , Biomarcadores/metabolismo , Disfunción Cognitiva/complicaciones , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Masculino
15.
Neuropharmacology ; 99: 675-88, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26302653

RESUMEN

Noribogaine is the long-lived human metabolite of the anti-addictive substance ibogaine. Noribogaine efficaciously reaches the brain with concentrations up to 20 µM after acute therapeutic dose of 40 mg/kg ibogaine in animals. Noribogaine displays atypical opioid-like components in vivo, anti-addictive effects and potent modulatory properties of the tolerance to opiates for which the mode of action remained uncharacterized thus far. Our binding experiments and computational simulations indicate that noribogaine may bind to the orthosteric morphinan binding site of the opioid receptors. Functional activities of noribogaine at G-protein and non G-protein pathways of the mu and kappa opioid receptors were characterized. Noribogaine was a weak mu antagonist with a functional inhibition constants (Ke) of 20 µM at the G-protein and ß-arrestin signaling pathways. Conversely, noribogaine was a G-protein biased kappa agonist 75% as efficacious as dynorphin A at stimulating GDP-GTP exchange (EC50=9 µM) but only 12% as efficacious at recruiting ß-arrestin, which could contribute to the lack of dysphoric effects of noribogaine. In turn, noribogaine functionally inhibited dynorphin-induced kappa ß-arrestin recruitment and was more potent than its G-protein agonistic activity with an IC50 of 1 µM. This biased agonist/antagonist pharmacology is unique to noribogaine in comparison to various other ligands including ibogaine, 18-MC, nalmefene, and 6'-GNTI. We predict noribogaine to promote certain analgesic effects as well as anti-addictive effects at effective concentrations>1 µM in the brain. Because elevated levels of dynorphins are commonly observed and correlated with anxiety, dysphoric effects, and decreased dopaminergic tone, a therapeutically relevant functional inhibition bias to endogenously released dynorphins by noribogaine might be worthy of consideration for treating anxiety and substance related disorders.


Asunto(s)
Analgésicos Opioides/farmacología , Ibogaína/análogos & derivados , Receptores Opioides kappa/agonistas , Analgésicos Opioides/química , Animales , Arrestinas/metabolismo , Células CHO , Simulación por Computador , Cricetulus , Evaluación Preclínica de Medicamentos , Dinorfinas/metabolismo , Proteínas de Unión al GTP/metabolismo , Humanos , Ibogaína/química , Ibogaína/farmacología , Mesencéfalo/efectos de los fármacos , Mesencéfalo/metabolismo , Ratones , Modelos Moleculares , Morfinanos/metabolismo , Ratas , Receptores Opioides kappa/metabolismo , Receptores Opioides mu/antagonistas & inhibidores , Receptores Opioides mu/metabolismo , Transducción de Señal/efectos de los fármacos , Trastornos Relacionados con Sustancias/prevención & control , beta-Arrestinas
16.
Biopolymers ; 104(6): 682-92, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26172377

RESUMEN

Peptide backbone cyclization is a widely used approach to improve the activity and stability of small peptides but until recently it had not been applied to peptides with multiple disulfide bonds. Conotoxins are disulfide-rich conopeptides derived from the venoms of cone snails that have applications in drug design and development. However, because of their peptidic nature, they can suffer from poor bioavailability and poor stability in vivo. In this study two P-superfamily conotoxins, gm9a and bru9a, were backbone cyclized by joining the N- and C-termini with short peptide linkers using intramolecular native chemical ligation chemistry. The cyclized derivatives had conformations similar to the native peptides showing that backbone cyclization can be applied to three disulfide-bonded peptides with cystine knot motifs. Cyclic gm9a was more potent at high voltage-activated (HVA) calcium channels than its acyclic counterpart, highlighting the value of this approach in developing active and stable conotoxins containing cyclic cystine knot motifs.


Asunto(s)
Conotoxinas/química , Ciclotidas/síntesis química , Secuencia de Aminoácidos , Animales , Conotoxinas/farmacología , Ciclización , Drosophila melanogaster , Ganglios Espinales/citología , Ganglios Espinales/efectos de los fármacos , Ganglios Espinales/fisiología , Datos de Secuencia Molecular , Espectroscopía de Protones por Resonancia Magnética , Ratas , Ratas Wistar , Homología de Secuencia de Aminoácido
17.
FASEB J ; 29(3): 1011-8, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25466886

RESUMEN

Nicotinic acetylcholine receptors (nAChRs) play a pivotal role in synaptic transmission of neuronal signaling pathways and are fundamentally involved in neuronal disorders, including Alzheimer's disease, Parkinson's disease, and schizophrenia. In vertebrates, cholinergic pathways can be selectively inhibited by α-conotoxins; we show that in the model organism Drosophila, the cholinergic component of the giant fiber system is inhibited by α-conotoxins MII, AuIB, BuIA, EI, PeIA, and ImI. The injection of 45 pmol/fly of each toxin dramatically decreases the response of the giant fiber to dorsal longitudinal muscle (GF-DLM) connection to 20 ± 13.9% for MII; 26 ± 13.7% for AuIB, 12 ± 9.9% for BuIA, 30 ± 11.3% for EI, 1 ± 1% for PeIA, and 34 ± 15.4% for ImI. Through bioassay-guided fractionation of the venom of Conus brunneus, we found BruIB, an α-conotoxin that inhibits Drosophila nicotinic receptors but not its vertebrate counterparts. GF-DLM responses decreased to 43.7 ± 8.02% on injection of 45 pmol/fly of BruIB. We manipulated the Dα7 nAChR to mimic the selectivity of its vertebrate counterpart by placing structurally guided point mutations in the conotoxin-binding site. This manipulation rendered vertebrate-like behavior in the Drosophila system, enhancing the suitability of Drosophila as an in vivo tool to carry out studies related to human neuronal diseases. .


Asunto(s)
Acetilcolina/farmacología , Conotoxinas/farmacología , Drosophila melanogaster/metabolismo , Antagonistas Nicotínicos/farmacología , Transmisión Sináptica/efectos de los fármacos , Receptor Nicotínico de Acetilcolina alfa 7/química , Receptor Nicotínico de Acetilcolina alfa 7/metabolismo , Secuencia de Aminoácidos , Animales , Animales Modificados Genéticamente/genética , Animales Modificados Genéticamente/crecimiento & desarrollo , Animales Modificados Genéticamente/metabolismo , Sitios de Unión , Colinérgicos/farmacología , Caracol Conus/química , Drosophila melanogaster/genética , Drosophila melanogaster/crecimiento & desarrollo , Femenino , Células Gigantes/citología , Células Gigantes/efectos de los fármacos , Células Gigantes/metabolismo , Humanos , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , Fibras Musculares Esqueléticas/citología , Fibras Musculares Esqueléticas/efectos de los fármacos , Fibras Musculares Esqueléticas/metabolismo , Mutación/genética , Oocitos/citología , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Fragmentos de Péptidos/farmacología , Conformación Proteica , Homología de Secuencia de Aminoácido , Xenopus laevis/metabolismo , Receptor Nicotínico de Acetilcolina alfa 7/genética
18.
Epigenomics ; 6(6): 637-49, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25531257

RESUMEN

Differentiation of neural stem/precursor cells (NS/PCs) into neurons, astrocytes and oligodendrocytes during mammalian brain development is a carefully controlled and timed event. Increasing evidences suggest that epigenetic regulation is necessary to drive this. Here, we provide an overview of the epigenetic mechanisms involved in the developing mammalian embryonic forebrain. Histone methylation is a key factor but other epigenetic factors such as DNA methylation and noncoding RNAs also partake during fate determination. As numerous epigenetic modifications have been identified, future studies on timing and regional specificity of these modifications will further deepen our understanding of how intrinsic and extrinsic mechanisms participate together to precisely control brain development.


Asunto(s)
Epigénesis Genética , Mamíferos/embriología , Células-Madre Neurales/citología , Animales , Encéfalo/crecimiento & desarrollo , Diferenciación Celular , Metilación de ADN , Histonas/metabolismo , Humanos , Mamíferos/genética , Células-Madre Neurales/fisiología , ARN no Traducido/metabolismo
19.
Exp Gerontol ; 54: 14-20, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24487345

RESUMEN

Centenarians are rare and exceptional individuals characterized by a peculiar phenotype. They are the best example of healthy aging in humans as most of them have escaped or substantially delayed the onset of major age-related diseases. Within this scenario, the purpose of the present work was to understand if immune status is associated with survival and health status in centenarians. To this aim, 116 centenarians were concomitantly characterized for their immunological, health and functional status, and followed-up for five-year survival. On the basis of previous knowledge we focused on a core of fundamental and basic immune parameters (number of leukocytes, monocytes, total lymphocytes, CD3(+) T lymphocytes, CD4(+) helper T lymphocytes, CD8(+) cytotoxic T lymphocytes, CD19(+) B lymphocytes and plasma levels of IgM), and the most important findings can be summarized as follows: i. a hierarchical cluster analysis was able to define Cluster1 (88 centenarians) and Cluster2 (28 centenarians) characterized by low and high values of all these immune parameters, respectively; ii. centenarians of Cluster2 showed a statistically longer five-year survival and more favorable values of other important immune (naïve, activated/memory and effector/memory T cells) and metabolic (glycemia, insulin and HOMA-IR) parameters, in accord with previous observations that centenarians have a peculiar immune profile, a preserved insulin pathway and a lower incidence of type 2 diabetes; and iii. unexpectedly, parameters related to frailty, as well as functional and cognitive status, did not show any significant correlation with the immune clustering, despite being capable per se of predicting survival. In conclusion, high values of basic immunological parameters and important T cell subsets correlate with five-year survival in centenarians, independent of other phenotypic characteristics. This unexpected biological scenario is compatible with the general hypothesis that in centenarians a progressive disconnection and loss of biological coherence among the different functions of the body occur, where survival/mortality result from the failure of any of these domains which apparently follow an independent age-related trajectory.


Asunto(s)
Inmunidad Adaptativa/fisiología , Estado de Salud , Anciano de 80 o más Años , Linfocitos B/inmunología , Análisis por Conglomerados , Diabetes Mellitus Tipo 2/inmunología , Femenino , Anciano Frágil , Humanos , Memoria Inmunológica/inmunología , Estimación de Kaplan-Meier , Masculino , Linfocitos T/inmunología
20.
Aging Clin Exp Res ; 26(4): 435-43, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24343853

RESUMEN

BACKGROUND: E-learning is an efficient and cost-effective educational method. AIMS: This study aimed at evaluating the feasibility of an educational e-learning intervention, focused on teaching geriatric pharmacology and notions of comprehensive geriatric assessment, to improve drug prescribing to hospitalized elderly patients. METHODS: Eight geriatric and internal medicine wards were randomized to intervention (e-learning educational program) or control. Clinicians of the two groups had to complete a specific per group e-learning program in 30 days. Then, ten patients (aged ≥75 years) had to be consecutively enrolled collecting clinical data at hospital admission, discharge, and 3 months later. The quality of prescription was evaluated comparing the prevalence of potentially inappropriate medications through Beer's criteria and of potential drug-drug interactions through a specific computerized database. RESULTS: The study feasibility was confirmed by the high percentage (90 %) of clinicians who completed the e-learning program, the recruitment, and follow-up of all planned patients. The intervention was well accepted by all participating clinicians who judged positively (a mean score of >3 points on a scale of 5 points: 0 = useless; 5 = most useful) the specific contents, the methodology applied, the clinical relevance and utility of e-learning contents and tools for the evaluation of the appropriateness of drug prescribing. CONCLUSIONS: The pilot study met all the requested goals. The main study is currently ongoing and is planned to finish on July 2015.


Asunto(s)
Aprendizaje/fisiología , Educación del Paciente como Asunto/métodos , Anciano , Anciano de 80 o más Años , Interacciones Farmacológicas/fisiología , Prescripciones de Medicamentos , Utilización de Medicamentos , Femenino , Evaluación Geriátrica/métodos , Geriatría/métodos , Hospitalización , Hospitales , Humanos , Internet , Masculino , Alta del Paciente , Proyectos Piloto , Prevalencia
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