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1.
Accid Anal Prev ; 193: 107337, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37820426

RESUMEN

AIMS / OBJECTIVES: This meta-analytic review examines the evidence for the relationship between cognitive function and driving performance in older adults. The primary aims of this review were: (a) to identify cognitive correlates of reduced driving performance in older adults and (b) to determine whether such measures reliably predict reductions in driving performance over time. METHODS: This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Peer reviewed studies that examined the (cross-sectional or longitudinal) relationship between standardised neuropsychological test performance measures and driving performance (e.g., via an on-road test, in-vehicle monitoring system, hazard perception test or driving simulator) in healthy adults aged 60 years and older, were included. RESULTS/DISCUSSION: Eighteen studies were eligible for inclusion, of which 12 met requirements for meta-analysis. The results indicated that reaction time and Trail Making Test (TMT) A scores exhibited small-to-moderate correlations with driving performance, with moderate effects identified for block design, TMT B, Useful Field of View (UFOV) 2 and 3 tests. Further, no significant relationships were observed between the Mini-Mental State Examination and UFOV 1 with driving performance. Due to a paucity of data, the longitudinal relationship between such measures and driving could not be identified. The findings highlight (a) the potential of cognitive assessments to identify older adults at risk of driving impairment (as part of a larger diagnostic assessment), and (b) the urgent need for prospective longitudinal studies in investigating the impact of age-related changes in cognition on driving performance over time.


Asunto(s)
Accidentes de Tránsito , Conducción de Automóvil , Humanos , Persona de Mediana Edad , Anciano , Estudios Prospectivos , Estudios Transversales , Accidentes de Tránsito/prevención & control , Pruebas Neuropsicológicas , Cognición
2.
Aust Crit Care ; 35(5): 543-549, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34556388

RESUMEN

BACKGROUND: Protein provision is thought to be integral to attenuating muscle wasting in critical illness, yet patients receive half of that prescribed. As international guidelines lack definitive evidence to support recommendations, understanding clinicians' views relating to protein practices is of importance. OBJECTIVES: The objective of this study was to describe Australia and New Zealand intensive care unit (ICU) dietitians' protein prescription and perceived delivery practices in critically ill adults, including common barriers and associations between ICU clinical experience and protein prescriptions for different clinical conditions. METHODS: A 42-item descriptive quantitative survey of Australian and New Zealand intensive care dietitians was disseminated through nutrition and ICU society e-mailing lists. Data were collected on respondent demographics and reported protein practices including questions related to a multitrauma case study. Data were analysed using descriptive and content analysis and reported as n (%). Fisher's exact tests were used to compare experience and protein prescriptions. RESULTS: Of the 67 responses received (one excluded due to >50% missing data), more than 80% of respondents stated they would prescribe 1.2-1.5 g protein/kg bodyweight/day for most critically ill patients, most commonly using European Society of Clinical Nutrition and Metabolism (ESPEN) guidelines to support prescriptions (n = 61/66, 92%). Most respondents (n = 49/66, 74%) thought their practice achieved 61-80% of protein prescriptions, with frequently reported barriers including fasting periods (n = 59/66, 89%), avoiding energy overfeeding (n = 50/66, 76%), and gastrointestinal intolerance (n = 47/66, 71%). No associations between years of ICU experience and protein prescriptions for 14 of the 15 predefined clinical conditions were present. CONCLUSIONS: Australian and New Zealand ICU dietitians use international guidelines to inform protein prescriptions of 1.2-1.5 g/kg/day for most clinical conditions, and protein prescriptions do not appear to be influenced by years of ICU experience. Key perceived barriers to protein delivery including avoidance of energy overfeeding and gastrointestinal intolerance could be explored to improve protein adequacy.


Asunto(s)
Enfermedad Crítica , Nutricionistas , Adulto , Australia , Cuidados Críticos , Proteínas de Unión al GTP , Humanos , Unidades de Cuidados Intensivos , Nueva Zelanda , Prescripciones , Encuestas y Cuestionarios
3.
Aust Crit Care ; 34(6): 569-572, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33663949

RESUMEN

BACKGROUND: In the critical care environment, elevated albuminuria values show capacity to reflect illness severity and predict mortality and hence assessing albumin/creatinine ratio (ACR) at the bedside has potential clinical benefit Point-of-care (POC) analysers offer rapid results but may be less accurate then laboratory analysis. METHODS: Critically ill adult patients with a urinary catheter in situ had albumin, creatinine, and ACR measurements performed via laboratory and POC analysis. Data are presented as mean (standard deviation) or median [interquartile range]. Measurement agreement was assessed by Lin's concordance correlation coefficient, Bland Altman 95% limits of agreement, and classification by Cohen's kappa statistic. RESULTS/FINDINGS: Albumin, creatinine, and ACR analysis was performed for 30 patients. Lin's correlation coefficient showed 'substantial' agreement for albumin and ACR and 'almost perfect' agreement for creatinine for POC vs laboratory analysis. POC vs laboratory analysis also showed poor agreement for identification of normal ACR (>1 mg/mmol) and mild urine ACR (1-3 mg/mmol) and 'substantial' agreement for moderately increased urine ACR (3-30 mg/mmol). CONCLUSIONS: ACR POC values appear to provide an accurate and rapid method that has potential to provide an early indication of injury severity and mortality risk in the critically ill.


Asunto(s)
Enfermedad Crítica , Sistemas de Atención de Punto , Adulto , Albúminas/análisis , Albuminuria , Creatinina , Humanos
4.
Mult Scler Relat Disord ; 50: 102831, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33618123

RESUMEN

BACKGROUND: Spasticity is a common problematic symptom in Multiple Sclerosis with over one third of patients failing first line therapies. Intrathecal baclofen is a safe and efficacious option for treatment resistant spasticity. Anecdotally patients report improved concentration/cognitive performance when switching to intrathecal baclofen (ITB) from systemic medications. AIM: To explore whether subjects who proceed with ITB pump implantation for spasticity management and reduce oral anti-spasticity agents will have improved cognitive function. METHODS: Subjects were admitted for trial of ITB via lumbar puncture and subsequent pump implantation. Spasticity and cognitive measures before ITB trial and 3 months post implant were recorded. Paired t-test or Wilcoxon Signed Ranks test was used for within subject change and effect sizes (Cohen's dz) were calculated. Subgroup analysis of those on ≥2, or ≤ 1 spasticity medications at baseline was performed. RESULTS: 27 subjects with MS completed per protocol. Mean age 46 years [26 - 56], disease duration 15 years [6 - 26], RRMS = 3, SPMS = 17 and PPMS=7. The majority were on multiple spasticity medications. Spasticity scores significantly improved post pump implant. Mean ITB dose at 3 months was 143 mcg / day and 19 discontinued all other treatments for spasticity. There was no deterioration on any cognitive or mood measure. An improvement of moderate effect size was found in Backwards Digit Span (d=0.41, p=0.059) and HADS - anxiety (d=0.37, p=0.097). Fatigue Severity Scale score decreased substantially (d=0.81, p=0.005). Small improvements in Symbol Digit Modalities Test score (d=0.24) and Sustained Attention to Response Task response time (d=0.23) were non-significant. Performance on other measures did not change. Effect sizes were larger in subgroup on ≥2 oral spasticity medications at baseline, compared to the group on ≤1 medication (SDMT, d=0.42 vs d=0.07; Backwards digit span 0.45 vs 0.28; HADS-anxiety 0.39 vs 0.32; HADS-depression d=0.32 vs 0.05 and FSS, d= 1.14 vs 0.42). CONCLUSIONS: In a pilot study exploring the impact of ITB on cognition, spasticity scores improved universally and beneficial effects on some measures of fatigue, anxiety, auditory attention and verbal working memory were found. Improvement of speed of processing in those withdrawing higher doses of oral medication was also demonstrated suggesting that switching to ITB has added cognitive and psychological benefits for people with MS.


Asunto(s)
Esclerosis Múltiple , Relajantes Musculares Centrales , Baclofeno/uso terapéutico , Cognición , Humanos , Inyecciones Espinales , Persona de Mediana Edad , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/tratamiento farmacológico , Relajantes Musculares Centrales/uso terapéutico , Espasticidad Muscular/tratamiento farmacológico , Espasticidad Muscular/etiología , Proyectos Piloto
5.
J Prev Alzheimers Dis ; 7(1): 37-42, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32010924

RESUMEN

In 358 participants of the Tasmanian Healthy Brain Project, we quantified the cognitive consequences of engaging in varying loads of university-level education in later life, and investigated whether or not BDNF Val66Met affected outcomes. Assessment of neuropsychological, health, and psychosocial function was undertaken at baseline, 12-month, and 24-month follow-up. Education load was positively associated with change in language processing performance, but this effect did not reach statistical significance (P = 0.064). The BDNF Val66Met polymorphism significantly moderated the extent to which education load was associated with improved language processing (P = 0.026), with education load having a significant positive relationship with cognitive change in BDNF Met carriers but not in BDNF Val homozygotes. In older adults who carry BDNF Met, engaging in university-level education improves language processing performance in a load-dependent manner.


Asunto(s)
Envejecimiento/genética , Factor Neurotrófico Derivado del Encéfalo/genética , Cognición , Polimorfismo Genético/genética , Rendimiento Académico , Anciano , Envejecimiento/fisiología , Estudios de Casos y Controles , Disfunción Cognitiva/prevención & control , Humanos , Persona de Mediana Edad , Pruebas Neuropsicológicas , Tasmania , Universidades
6.
Astrobiology ; 19(7): 831-848, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30907634

RESUMEN

We present the case for the presence of complex organic molecules, such as amino acids and nucleobases, formed by abiotic processes on the surface and in near-subsurface regions of Pluto. Pluto's surface is tinted with a range of non-ice substances with colors ranging from light yellow to red to dark brown; the colors match those of laboratory organic residues called tholins. Tholins are broadly characterized as complex, macromolecular organic solids consisting of a network of aromatic structures connected by aliphatic bridging units (e.g., Imanaka et al., 2004; Materese et al., 2014, 2015). The synthesis of tholins in planetary atmospheres and in surface ices has been explored in numerous laboratory experiments, and both gas- and solid-phase varieties are found on Pluto. A third variety of tholins, exposed at a site of tectonic surface fracturing called Virgil Fossae, appears to have come from a reservoir in the subsurface. Eruptions of tholin-laden liquid H2O from a subsurface aqueous repository appear to have covered portions of Virgil Fossae and its surroundings with a uniquely colored deposit (D.P. Cruikshank, personal communication) that is geographically correlated with an exposure of H2O ice that includes spectroscopically detected NH3 (C.M. Dalle Ore, personal communication). The subsurface organic material could have been derived from presolar or solar nebula processes, or might have formed in situ. Photolysis and radiolysis of a mixture of ices relevant to Pluto's surface composition (N2, CH4, CO) have produced strongly colored, complex organics with a significant aromatic content having a high degree of nitrogen substitution similar to the aromatic heterocycles pyrimidine and purine (Materese et al., 2014, 2015; Cruikshank et al., 2016). Experiments with pyrimidines and purines frozen in H2O-NH3 ice resulted in the formation of numerous nucleobases, including the biologically relevant guanine, cytosine, adenine, uracil, and thymine (Materese et al., 2017). The red material associated with the H2O ice may contain nucleobases resulting from energetic processing on Pluto's surface or in the interior. Some other Kuiper Belt objects also exhibit red colors similar to those found on Pluto and may therefore carry similar inventories of complex organic materials. The widespread and ubiquitous nature of similarly complex organic materials observed in a variety of astronomical settings drives the need for additional laboratory and modeling efforts to explain the origin and evolution of organic molecules. Pluto observations reveal complex organics on a small body that remains close to its place of origin in the outermost regions of the Solar System.


Asunto(s)
Atmósfera/análisis , Medio Ambiente Extraterrestre/química , Plutón , Purinas/análisis , Pirimidinas/análisis , Atmósfera/química , Hielo , Metano/análisis , Espectrofotometría Infrarroja , Compuestos Orgánicos Volátiles/análisis , Agua/química
7.
J Geophys Res Space Phys ; 124(9): 7413-7424, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35860291

RESUMEN

Pluto energies of a few kiloelectron volts and suprathermal ions with tens of kiloelectron volts and above. We measure this population using the Pluto Energetic Particle Spectrometer Science Investigation (PEPSSI) instrument on board the New Horizons spacecraft that flew by Pluto in 2015. Even though the measured ions have gyroradii larger than the size of Pluto and the cross section of its magnetosphere, we find that the boundary of the magnetosphere is depleting the energetic ion intensities by about an order of magnitude close to Pluto. The intensity is increasing exponentially with distance to Pluto and reaches nominal levels of the interplanetary medium at about 190R P distance. Inside the wake of Pluto, we observe oscillations of the ion intensities with a periodicity of about 0.2 hr. We show that these can be quantitatively explained by the electric field of an ultralow-frequency wave and discuss possible physical drivers for such a field. We find no evidence for the presence of plutogenic ions in the considered energy range.

8.
Transl Psychiatry ; 7(6): e1144, 2017 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-28585929

RESUMEN

The S allele of the functional 5-HTTLPR polymorphism has previously been associated with reductions in memory function. Given the change in function of the serotonergic system in older adults, and the functional consequences of memory decline in this age group, further investigation into the impact of 5-HTTLPR in healthy older adults is required. This investigation examined the effect of 5-HTTLPR variants (S carriers versus L/L homozygotes) on verbal and visual episodic memory in 438 healthy older adults participating in the Tasmanian Healthy Brain Project (age range 50-79 years, M=60.35, s.d.=6.75). Direct effects of 5-HTTLPR on memory processes, in addition to indirect effects through interaction with age and gender, were assessed. Although no direct effects of 5-HTTLPR on memory processes were identified, our results indicated that gender significantly moderated the impact that 5-HTTLPR variants exerted on the relationship between age and verbal episodic memory function as assessed by the Rey Auditory Verbal Learning Test. No significant direct or indirect effects were identified in relation to visual memory performance. Overall, this investigation found evidence to suggest that 5-HTTLPR genotype affects the association of age and verbal episodic memory for males and females differently, with the predicted negative effect of S carriage present in males but not females. Such findings indicate a gender-dependent role for 5-HTTLPR in the verbal episodic memory system of healthy older adults.


Asunto(s)
Genotipo , Memoria Episódica , Polimorfismo de Nucleótido Simple , Proteínas de Transporte de Serotonina en la Membrana Plasmática/genética , Aprendizaje Verbal/fisiología , Anciano , Alelos , Femenino , Estudios de Asociación Genética , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores Sexuales
9.
Acta Anaesthesiol Scand ; 61(2): 216-223, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27966213

RESUMEN

BACKGROUND: The objectives of this study were to estimate the frequency of occult upper gastrointestinal abnormalities, presence of gastric acid as a contributing factor, and associations with clinical outcomes. METHODS: Data were extracted for study participants at a single centre who had an endoscopy performed purely for research purposes and in whom treating physicians were not suspecting gastrointestinal bleeding. Endoscopic data were independently adjudicated by two gastroenterologists who rated the likelihood that observed pathological abnormalities were related to gastric acid secretion using a 3-point ordinal scale (unlikely, possible or probable). RESULTS: Endoscopy reports were extracted for 74 patients [age 52 (37, 65) years] undergoing endoscopy on day 5 [3, 9] of ICU admission. Abnormalities were found in 25 (34%) subjects: gastritis/erosions in 10 (14%), nasogastric tube trauma in 8 (11%), oesophagitis in 4 (5%) and non-bleeding duodenal ulceration in 3 (4%). The contribution of acid secretion to observed pathology was rated 'probable' in six subjects (rater #1) and five subjects (rater #2). Prior to endoscopy, 39 (53%) patients were receiving acid-suppressive therapy. The use of acid-suppressive therapy was not associated with the presence of an endoscopic abnormality (present 15/25 (60%) vs. absent 24/49 (49%); P = 0.46). Haemoglobin concentrations, packed red cells transfused and mortality were not associated with mucosal abnormalities (P = 0.83, P > 0.9 and P > 0.9 respectively). CONCLUSIONS: Occult mucosal abnormalities were observed in one-third of subjects. The presence of mucosal abnormalities appeared to be independent of prior acid-suppressive therapy and was not associated with reduced haemoglobin concentrations, increased transfusion requirements, or mortality.


Asunto(s)
Enfermedad Crítica , Esofagitis/patología , Gastritis/patología , Mucosa Intestinal/patología , Adulto , Anciano , Endoscopía Gastrointestinal , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Inhibidores de la Bomba de Protones/uso terapéutico
10.
Geobiology ; 15(1): 173-183, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27527874

RESUMEN

Hopanes are abundant in ancient sedimentary rocks at discrete intervals in Earth history, yet interpreting their significance in the geologic record is complicated by our incomplete knowledge of what their progenitors, hopanoids, do in modern cells. To date, few studies have addressed the breadth of diversity of physiological functions of these lipids and whether those functions are conserved across the hopanoid-producing bacterial phyla. Here, we generated mutants in the filamentous cyanobacterium, Nostoc punctiforme, that are unable to make all hopanoids (shc) or 2-methylhopanoids (hpnP). While the absence of hopanoids impedes growth of vegetative cells at high temperature, the shc mutant grows faster at low temperature. This finding is consistent with hopanoids acting as membrane rigidifiers, a function shared by other hopanoid-producing phyla. Apart from impacting fitness under temperature stress, hopanoids are dispensable for vegetative cells under other stress conditions. However, hopanoids are required for stress tolerance in akinetes, a resting survival cell type. While 2-methylated hopanoids do not appear to contribute to any stress phenotype, total hopanoids and to a lesser extent 2-methylhopanoids were found to promote the formation of cyanophycin granules in akinetes. Finally, although hopanoids support symbiotic interactions between Alphaproteobacteria and plants, they do not appear to facilitate symbiosis between N. punctiforme and the hornwort Anthoceros punctatus. Collectively, these findings support interpreting hopanes as general environmental stress biomarkers. If hopanoid-mediated enhancement of nitrogen-rich storage products turns out to be a conserved phenomenon in other organisms, a better understanding of this relationship may help us parse the enrichment of 2-methylhopanes in the rock record during episodes of disrupted nutrient cycling.


Asunto(s)
Nostoc/fisiología , Estrés Fisiológico , Triterpenos/metabolismo , Mutación , Nostoc/genética , Nostoc/metabolismo , Nostoc/efectos de la radiación , Temperatura
11.
Nature ; 539(7627): 65-68, 2016 11 03.
Artículo en Inglés | MEDLINE | ID: mdl-27626378

RESUMEN

A unique feature of Pluto's large satellite Charon is its dark red northern polar cap. Similar colours on Pluto's surface have been attributed to tholin-like organic macromolecules produced by energetic radiation processing of hydrocarbons. The polar location on Charon implicates the temperature extremes that result from Charon's high obliquity and long seasons in the production of this material. The escape of Pluto's atmosphere provides a potential feedstock for a complex chemistry. Gas from Pluto that is transiently cold-trapped and processed at Charon's winter pole was proposed as an explanation for the dark coloration on the basis of an image of Charon's northern hemisphere, but not modelled quantitatively. Here we report images of the southern hemisphere illuminated by Pluto-shine and also images taken during the approach phase that show the northern polar cap over a range of longitudes. We model the surface thermal environment on Charon and the supply and temporary cold-trapping of material escaping from Pluto, as well as the photolytic processing of this material into more complex and less volatile molecules while cold-trapped. The model results are consistent with the proposed mechanism for producing the observed colour pattern on Charon.

12.
Science ; 351(6279): aae0030, 2016 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-26989256

RESUMEN

The New Horizons mission has provided resolved measurements of Pluto's moons Styx, Nix, Kerberos, and Hydra. All four are small, with equivalent spherical diameters of ~40 kilometers for Nix and Hydra and ~10 kilometers for Styx and Kerberos. They are also highly elongated, with maximum to minimum axis ratios of ~2. All four moons have high albedos (~50 to 90%) suggestive of a water-ice surface composition. Crater densities on Nix and Hydra imply surface ages of at least 4 billion years. The small moons rotate much faster than synchronous, with rotational poles clustered nearly orthogonal to the common pole directions of Pluto and Charon. These results reinforce the hypothesis that the small moons formed in the aftermath of a collision that produced the Pluto-Charon binary.

13.
Transl Psychiatry ; 5: e590, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26125153

RESUMEN

The concept of cognitive reserve (CR) has been proposed to account for observed discrepancies between pathology and its clinical manifestation due to underlying differences in brain structure and function. In 433 healthy older adults participating in the Tasmanian Healthy Brain Project, we investigated whether common polymorphic variations in apolipoprotein E (APOE) or brain-derived neurotrophic factor (BDNF) influenced the association between CR contributors and cognitive function in older adults. We show that BDNF Val66Met moderates the association between CR and executive function. CR accounted for 8.5% of the variance in executive function in BDNF Val homozygotes, but CR was a nonsignificant predictor in BDNF Met carriers. APOE polymorphisms were not linked to the influence of CR on cognitive function. This result implicates BDNF in having an important role in capacity for building or accessing CR.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/genética , Reserva Cognitiva , Función Ejecutiva , Anciano , Apolipoproteínas E/genética , Cognición , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo Genético
14.
J Musculoskelet Neuronal Interact ; 15(2): 161-70, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26032208

RESUMEN

Neurofibromatosis Type 1 (NF1) is a genetic neurocutaneous disorder with multisystem manifestations, including a predisposition to tumor formation and bone dysplasias. Studies over the last decade have shown that NF1 can also be associated with significant motor deficits, such as poor coordination, low muscle tone, and easy fatigability. These have traditionally been ascribed to developmental central nervous system and cognitive deficits. However, recent preclinical studies have also illustrated a primary role for the NF1 gene product in muscle growth and metabolism; these findings are consistent with clinical studies demonstrating reduced muscle size and muscle weakness in individuals with NF1. Currently there is no evidence-based intervention for NF1 muscle and motor deficiencies; this review identifies key research areas where improved mechanistic understanding could unlock new therapeutic options.


Asunto(s)
Trastornos del Movimiento/fisiopatología , Músculo Esquelético/patología , Neurofibromatosis 1/patología , Adolescente , Adulto , Niño , Medicina Basada en la Evidencia , Femenino , Humanos , Masculino , Músculo Esquelético/fisiopatología , Neurofibromatosis 1/fisiopatología , Neurofibromatosis 1/terapia , Adulto Joven
15.
Cell Death Dis ; 5: e1462, 2014 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-25321469

RESUMEN

Cancer cell proliferation relies on the ability of cancer cells to grow, transition through the cell cycle, and divide. To identify novel chemical probes for dissecting the mechanisms governing cell cycle progression and cell division, and for developing new anti-cancer therapeutics, we developed and performed a novel cancer cell-based high-throughput chemical screen for cell cycle modulators. This approach identified novel G1, S, G2, and M-phase specific inhibitors with drug-like properties and diverse chemotypes likely targeting a broad array of processes. We further characterized the M-phase inhibitors and highlight the most potent M-phase inhibitor MI-181, which targets tubulin, inhibits tubulin polymerization, activates the spindle assembly checkpoint, arrests cells in mitosis, and triggers a fast apoptotic cell death. Importantly, MI-181 has broad anti-cancer activity, especially against BRAF(V600E) melanomas.


Asunto(s)
Antineoplásicos/farmacología , Ciclo Celular/efectos de los fármacos , Descubrimiento de Drogas , Ensayos Analíticos de Alto Rendimiento/métodos , Sondas Moleculares/farmacología , Antineoplásicos/uso terapéutico , Muerte Celular/efectos de los fármacos , Células HeLa , Humanos , Puntos de Control de la Fase M del Ciclo Celular/efectos de los fármacos , Mitosis/efectos de los fármacos , Neoplasias/tratamiento farmacológico , Fenotipo , Polimerizacion/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/análisis , Bibliotecas de Moléculas Pequeñas/farmacología , Tubulina (Proteína)/metabolismo
16.
Eur J Neurol ; 21(10): 1330-6, e82-3, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24943259

RESUMEN

BACKGROUND AND PURPOSE: Longitudinal studies of mild cognitive impairment (MCI) report that a sizeable proportion of MCI cases revert to normal levels of functioning over time. The rate of recovery from MCI indicates that existing MCI diagnostic criteria result in an unacceptably high rate of false positive diagnoses and lack adequate sensitivity and specificity. METHODS: The aim of the present study was to identify a set of neuropsychological measures able to differentiate between true positive cases of MCI from those who were unimpaired at 11 months' follow-up. RESULTS: A discriminant function analysis identified that a combination of measures of complex sustained attention, semantic memory, working memory, episodic memory and selective attention correctly classified outcome in more than 80% of cases. The rate of false positive diagnoses (5.93%) was considerably lower than is evident in previously published MCI studies. CONCLUSIONS: The results of the present study indicate that the rate of false positive MCI diagnoses can be significantly reduced through the use of sensitive and specific neuropsychological measures of memory and non-memory functions.


Asunto(s)
Disfunción Cognitiva/diagnóstico , Pruebas Neuropsicológicas/normas , Sensibilidad y Especificidad , Anciano , Femenino , Humanos , Estudios Longitudinales , Masculino
17.
Acta Anaesthesiol Scand ; 58(2): 235-42, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24410108

RESUMEN

BACKGROUND: In health, the hormones amylin and glucagon-like peptide-1 (GLP-1) slow gastric emptying (GE) and modulate glycaemia. The aims of this study were to determine amylin and GLP-1 concentrations in the critically ill and their relationship with GE, glucose absorption and glycaemia. METHODS: In fasted critically ill and healthy subjects (n = 26 and 23 respectively), liquid nutrient, containing 100 mg (13) C-sodium octanoate and 3 g 3-O-methlyglucose (3-OMG), was administered via a nasogastric tube. Amylin, GLP-1, glucose and 3-OMG concentrations were measured in blood samples taken during fasting, and 30 min and 60 min after the 'meal'. Breath samples were taken to determine gastric emptying coefficient (GEC). Intolerance to intragastric feeding was defined as a gastric residual volume of ≥ 250 ml and/or vomiting within the 24 h prior to the study. RESULTS: Although GE was slower (GEC: critically ill 2.8 ± 0.9 vs. health, 3.4 ± 0.2; P = 0.002), fasting blood glucose was higher (7.0 ± 1.9 vs. 5.7 ± 0.2 mmol/l; P = 0.005) and overall glucose absorption was reduced in critically ill patients (3-OMG: 9.4 ± 8.0 vs. 17.7 ± 4.9 mmol/l.60 min; P < 0.001), there were no differences in fasting or postprandial amylin concentrations. Furthermore, although fasting [1.7 (0.4-7.2) vs. 0.7 (0.3-32.0) pmol/l; P = 0.04] and postprandial [3.0 (0.4-8.5) vs. 0.8 (0.4-34.3) pmol/l; P = 0.02] GLP-1 concentrations were increased in the critically ill and were greater in feed intolerant when compared with those tolerating feed [3.7 (0.4-7.2) vs. 1.2 (0.7-4.6) pmol/l; P = 0.02], there were no relationships between GE and fasting amylin or GLP-1 concentrations. CONCLUSION: In the critically ill, fasting GLP-1, but not amylin, concentrations are elevated and associated with feed intolerance. Neither amylin nor GLP-1 appears to substantially influence the rate of GE.


Asunto(s)
Enfermedad Crítica , Vaciamiento Gástrico/fisiología , Péptido 1 Similar al Glucagón/sangre , Polipéptido Amiloide de los Islotes Pancreáticos/sangre , 3-O-Metilglucosa/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Glucemia/metabolismo , Pruebas Respiratorias , Estudios de Cohortes , Femenino , Glucosa/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
18.
Eur J Neurol ; 21(3): 470-7, e23-4, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24372923

RESUMEN

BACKGROUND AND PURPOSE: Previous research examining mild cognitive impairment (MCI) has highlighted the heterogeneity of outcome in MCI sufferers. MCI is associated with greater risk of progression to dementia; however, a substantial proportion of those identified with MCI have alternative outcomes including recovery to unimpaired status. This heterogeneity may in part reflect insufficient sensitivity and specificity in identifying subclinical memory impairment. METHOD: The present study examined learning in a sample of 109 adults aged 61-91 years with persistent amnestic MCI, persistent non-amnestic MCI, recovered MCI and healthy controls. At the final assessment point, learning for words recalled across each trial of the Rey Auditory Verbal Learning Test was examined for each group. RESULTS: It was found that persistent amnestic MCI participants displayed significantly lower learning compared with recovered MCI and healthy control groups. DISCUSSION: The results of this study indicated that poor learning across trials may be a defining feature of persistent amnestic MCI. Further research is required to establish the predictive utility of within trial list learning performance to identify individuals with persistent and progressive variants of MCI.


Asunto(s)
Amnesia/complicaciones , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/diagnóstico , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Sensibilidad y Especificidad
19.
Cell Death Differ ; 20(5): 721-31, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23348568

RESUMEN

A large number of patients are resistant to taxane-based chemotherapy. Functional mitotic checkpoints are essential for taxane sensitivity. Thus, mitotic regulators are potential markers for therapy response and could be targeted for anticancer therapy. In this study, we identified a novel function of ubiquitin (Ub)-specific processing protease-7 (USP7) that interacts and cooperates with protein death domain-associated protein (Daxx) in the regulation of mitosis and taxane resistance. Depletion of USP7 impairs mitotic progression, stabilizes cyclin B and reduces stability of the mitotic E3 Ub ligase, checkpoint with forkhead and Ring-finger (CHFR). Consequently, cells with depleted USP7 accumulate Aurora-A kinase, a CHFR substrate, thus elevating multipolar mitoses. We further show that these effects are independent of the USP7 substrate p53. Thus, USP7 and Daxx are necessary to regulate proper execution of mitosis, partially via regulation of CHFR and Aurora-A kinase stability. Results from colony formation assay, in silico analysis across the NCI60 platform and in breast cancer patients suggest that USP7 levels inversely correlate with response to taxanes, pointing at the USP7 protein as a potential predictive factor for taxane response in cancer patients. In addition, we demonstrated that inhibition of Aurora-A attenuates USP7-mediated taxane resistance, suggesting that combinatorial drug regimens of Taxol and Aurora-A inhibitors may improve the outcome of chemotherapy response in cancer patients resistant to taxane treatment. Finally, our study offers novel insights on USP7 inhibition as cancer therapy.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Antineoplásicos/farmacología , Hidrocarburos Aromáticos con Puentes/farmacología , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Taxoides/farmacología , Ubiquitina Tiolesterasa/metabolismo , Antineoplásicos/uso terapéutico , Aurora Quinasas , Benzazepinas/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Hidrocarburos Aromáticos con Puentes/uso terapéutico , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Proteínas Co-Represoras , Ciclina B/metabolismo , Resistencia a Antineoplásicos , Femenino , Humanos , Mitosis , Chaperonas Moleculares , Proteínas de Neoplasias/metabolismo , Proteínas de Unión a Poli-ADP-Ribosa , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Interferencia de ARN , ARN Interferente Pequeño , Taxoides/uso terapéutico , Proteína p53 Supresora de Tumor , Ubiquitina Tiolesterasa/genética , Ubiquitina-Proteína Ligasas , Peptidasa Específica de Ubiquitina 7
20.
Intensive Care Med ; 39(2): 258-66, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23096428

RESUMEN

PURPOSE: To compare nutrient-stimulated changes in superior mesenteric artery (SMA) blood flow, glucose absorption and glycaemia in individuals older than 65 years with, and without, critical illness. METHODS: Following a 1-h 'observation' period (t (0)-t (60)), 0.9 % saline and glucose (1 kcal/ml) were infused directly into the small intestine at 2 ml/min between t (60)-t (120), and t (120)-t (180), respectively. SMA blood flow was measured using Doppler ultrasonography at t (60) (fasting), t (90) and t (150) and is presented as raw values and nutrient-stimulated increment from baseline (Δ). Glucose absorption was evaluated using serum 3-O-methylglucose (3-OMG) concentrations during, and for 1 h after, the glucose infusion (i.e. t (120)-t (180) and t (120)-t (240)). Mean arterial pressure was recorded between t (60)-t (240). Data are presented as median (25th, 75th percentile). RESULTS: Eleven mechanically ventilated critically ill patients [age 75 (69, 79) years] and nine healthy volunteers [70 (68, 77) years] were studied. The magnitude of the nutrient-stimulated increase in SMA flow was markedly less in the critically ill when compared with healthy subjects [Δt (150): patients 115 (-138, 367) versus health 836 (618, 1,054) ml/min; P = 0.001]. In patients, glucose absorption was reduced during, and for 1 h after, the glucose infusion when compared with health [AUC(120-180): 4.571 (2.591, 6.551) versus 11.307 (8.447, 14.167) mmol/l min; P < 0.001 and AUC(120-240): 26.5 (17.7, 35.3) versus 40.6 (31.7, 49.4) mmol/l min; P = 0.031]. A close relationship between the nutrient-stimulated increment in SMA flow and glucose absorption was evident (3-OMG AUC(120-180) and ∆SMA flow at t (150): r (2) = 0.29; P < 0.05). CONCLUSIONS: In critically ill patients aged >65 years, stimulation of SMA flow by small intestinal glucose infusion may be attenuated, which could account for the reduction in glucose absorption.


Asunto(s)
Presión Sanguínea , Enfermedad Crítica , Glucosa/administración & dosificación , Glucosa/metabolismo , Absorción Intestinal , Mesenterio/irrigación sanguínea , Anciano , Femenino , Humanos , Intestino Delgado , Masculino , Flujo Sanguíneo Regional
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