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1.
Eur J Neurol ; 27(6): 995-1002, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32078209

RESUMEN

BACKGROUND AND PURPOSE: Memory is known to be the most common first symptom in Alzheimer's disease (AD). Assessing non-memory cognitive symptom development in AD is important for understanding disease progression and the potential identification of treatment-responsive subtypes. METHODS: Data from the National Alzheimer's Coordinating Center were examined. Logistic regression models were fitted evaluating the development of judgement, language, visuospatial and attention symptoms at first and second visits to Alzheimer's Disease Centers. Predictors were age and prior symptoms, adjusting for symptom length and sex. The models were then refitted assessing apolipoprotein E ε4 (APOE-ε4) effects. RESULTS: Each decade reduction in presentation age increased the odds of language, visuospatial and attention symptom development at both visits by 8%-18% (P < 0.05, all tests), and judgement symptoms at the second visit by 13% (P < 0.05). Prior symptoms were not equally predictive of symptom development. For example, having first predominant language symptoms carried the lowest risk of developing other first-visit symptoms and having memory symptoms was a stronger predictor of developing judgement than other symptoms. The APOE-ε4 gene showed little impact on symptom development when included as a predictor. CONCLUSIONS: Our findings provide support for the concept that younger-onset AD is associated with the progressive development of more non-memory symptoms beyond the first time point. Associations between symptoms were evident, which may reflect that pathology can remain isolated in a network for some time. APOE-ε4 status had little influence on cognitive symptom development which may indicate that the effect it has occurs very early in the disease course.


Asunto(s)
Enfermedad de Alzheimer , Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Apolipoproteína E4 , Cognición , Humanos , Memoria , Pruebas Neuropsicológicas
2.
Phytother Res ; 32(6): 1080-1089, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29464872

RESUMEN

The objectives of this paper is to investigate, demonstrate, and compare the mechanism of action of phytocannabinoids as antidiabetic and anti-obesity agents in preadipocytes and adipocytes, relative to rosiglitazone and metformin. Briefly, cannabis extract, Δ9 -tetrahydrocannabinol and cannabidiol (in very low dosages) were shown to promote glucose uptake higher or to equivalent levels, reduce fat accumulation, and reverse the insulin-resistant state of 3T3-L1 cells more effectively, relative to rosiglitazone and metformin. The phytocannabinoids had a more pronounced effect in preadipocytes undifferentiated model rather than the differentiated model. They induced a protective effect at the mitochondrial level by preventing overactivity of the succinate dehydrogenase pathway (p < .01), unlike rosiglitazone, through activation of the glycerol-3-phosphate dehydrogenase shuttling system. An increase in oxygen consumption and an increased expression of beta to alpha adrenoceptors (p < .05) in treated cells were noted. These findings contribute toward understanding the mechanism of action of phytocannabinoids in fat cells and highlight the antidiabetic and anti-obesity properties of various phytocannabinoids that could potentially support the treatment of obesity-related insulin resistance.


Asunto(s)
Adipocitos/efectos de los fármacos , Fármacos Antiobesidad/uso terapéutico , Cannabinoides/uso terapéutico , Hipoglucemiantes/uso terapéutico , Extractos Vegetales/uso terapéutico , Animales , Fármacos Antiobesidad/farmacología , Cannabinoides/farmacología , Cannabis , Hipoglucemiantes/farmacología , Ratones , Extractos Vegetales/farmacología
3.
J Appl Microbiol ; 122(4): 921-931, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28132403

RESUMEN

AIMS: This study investigates the effect that aqueous extracts of Tulbaghia violacea Harv. harbouring plant saponins, phenolics and tannins have on Aspergillus flavus ß-(1,3) glucan and chitin synthesis. METHODS AND RESULTS: Aspergillus flavus was treated with various subinhibitory concentrations of an aqueous T. violacea plant extract and the ß-(1,3) glucan and chitin content was determined together with glucan synthase and chitin synthase production respectively. CONCLUSIONS: The aqueous extract caused a significant decline (P < 0·05) in ß-glucan production in A. flavus in a dose-dependent manner when compared to the untreated sample. Further investigations showed a decrease in ß-glucan synthase production as the concentration of the plant extract was increased. A significant reduction in total chitin content corresponding to a decrease in chitin synthase production in the presence of the plant extract was also found. SIGNIFICANCE AND IMPACT OF THE STUDY: The broad spectrum activity and the efficacy of aqueous T. violacea plant extract on both ß-glucan and chitin synthesis may limit the potential of the fungus developing resistance towards it and therefore the extract is an ideal candidate for use as a potential antifungal agent.


Asunto(s)
Allium/química , Antifúngicos/farmacología , Aspergillus flavus/efectos de los fármacos , Antifúngicos/química , Antifúngicos/metabolismo , Aspergillus flavus/enzimología , Aspergillus flavus/metabolismo , Pared Celular/efectos de los fármacos , Pared Celular/metabolismo , Quitina/metabolismo , Glucanos/farmacología , Glucosiltransferasas/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , beta-Glucanos/metabolismo
4.
Clin Radiol ; 72(1): 41-51, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27927488

RESUMEN

AIM: To evaluate major/minor discrepancy rates for provisional (initial) and addendum (supplementary senior review) emergency computed tomography (CT) reports in patients presenting with non-traumatic abdominal pain. MATERIALS AND METHODS: Ethical approval for this type of study is not required in the UK. All radiology departments with an approved lead for audit registered with the Royal College of Radiologists were invited to participate in this retrospective audit. The first 50 consecutive patients (25 surgical, 25 non-surgical) who underwent emergency abdominal CT for non-traumatic abdominal pain in 2013 were included. Statistical analyses were performed to identify organisational and report/patient-related variables that might be associated with major discrepancy. RESULTS: One hundred and nine (58%) of 188 departments supplied data to the study with a total of 4,931 patients (2,568 surgical, 2,363 non-surgical). The audit standard for provisional report major discrepancy was achieved for registrars (target <10%, achieved 4.6%), for on-site consultants (target <5%, achieved 3.1%) and consultant addendum (target <5%, achieved 2.9%). Off-site reporters failed to meet the standard target (<5%, achieved 8.7% overall and 12.7% in surgical patients). The standard for patients coming to harm was not met in the surgical group (target <1%, achieved 1.5%) and was narrowly missed overall (target <1%, achieved 1%). CONCLUSION: This study should be used to provide impetus to improve aspects of out-of-hours CT reporting. Clear benefits of CT interpretation/review by on-site and more senior (consultant) radiologists have been demonstrated.


Asunto(s)
Dolor Abdominal/diagnóstico por imagen , Dolor Abdominal/epidemiología , Errores Diagnósticos/estadística & datos numéricos , Servicios Médicos de Urgencia/estadística & datos numéricos , Radiografía Abdominal/estadística & datos numéricos , Tomografía Computarizada por Rayos X/estadística & datos numéricos , Traumatismos Abdominales/diagnóstico , Traumatismos Abdominales/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Competencia Clínica , Errores Diagnósticos/prevención & control , Femenino , Humanos , Masculino , Auditoría Médica , Persona de Mediana Edad , Variaciones Dependientes del Observador , Prevalencia , Reproducibilidad de los Resultados , Factores de Riesgo , Sensibilidad y Especificidad , Reino Unido/epidemiología , Adulto Joven
5.
Cell Prolif ; : e13650, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38721827

RESUMEN

Studies have shown that natural products can induce paraptosis in tumour cell lines. Paraptosis is characterized by cytoplasmic vacuolation arising from the endoplasmic reticulum (ER) and mitochondria. The mechanism of paraptosis is unclear; however, dysregulation of Ca2+ homeostasis is believed to affect paraptosis induction. This study investigated the mechanism of cell death induced by a phytocannabinoid ratio in the MCF7 breast cancer cell line. The crystal violet assay was used to detect changes in viability and morphology changes were investigated using light and transmission electron microscopy. Various inhibitors, fluorescent staining with high-content screening, and Western blot analysis were used to investigate different cell death mechanisms. The phytocannabinoid ratio induced significant cell death and cytoplasmic vacuolation in MCF7 cells; however, no apoptosis, necrosis, autophagy, or ferroptosis was detected. Vacuolation induced by phytocannabinoid treatment was inhibited by cycloheximide, suggesting paraptosis induction. The mechanism of paraptosis induction was investigated, and it was found that treatment (1) induced ER dilation and mitochondrial swelling, (2) induced significant ER stress and mitochondrial Ca2+ overload and dysfunction, which appeared to be mediated by the voltage-dependent anion channel, and (3) significantly impaired all mitochondrial metabolic pathways. The data demonstrated that paraptosis induced by the cannabinoid ratio was mediated by Ca2+ flux from the ER to the mitochondria. These findings highlight a novel mechanism of cannabinoid-induced cell death and emphasize the anti-cancer potential of cannabinoid ratios, which exhibited enhanced effects compared to individual cannabinoids.

6.
Phys Rev Lett ; 111(13): 137205, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-24116814

RESUMEN

The space-and time-dependent response of many-body quantum systems is the most informative aspect of their emergent behavior. The dynamical structure factor, experimentally measurable using neutron scattering, can map this response in wave vector and energy with great detail, allowing theories to be quantitatively tested to high accuracy. Here, we present a comparison between neutron scattering measurements on the one-dimensional spin-1/2 Heisenberg antiferromagnet KCuF3, and recent state-of-the-art theoretical methods based on integrability and density matrix renormalization group simulations. The unprecedented quantitative agreement shows that precise descriptions of strongly correlated states at all distance, time, and temperature scales are now possible, and highlights the need to apply these novel techniques to other problems in low-dimensional magnetism.

7.
J Evol Biol ; 25(3): 522-31, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22239486

RESUMEN

Body size and morphology are key fitness-determining traits that can vary genotypically. They are likely to be important in social insect queens, which mate in swarms and found colonies independently, but genetic influences on queen morphology have been little investigated. Here, we show that the body size and morphology of queens are influenced by their genotype in the leaf-cutting ant Acromyrmex echinatior, a species in which certain lineages (patrilines) bias their development towards reproductive queens rather than sterile workers. We found no relationship between the queen-worker skew of patrilines and the size or morphology of queens, but there was a significant relationship with fluctuating asymmetry, which was greater in more queen-biased patrilines. Our results suggest that queen-biased patrilines do not incur a fitness cost in terms of body size, but may face more subtle costs in developmental stability. Such costs may constrain the evolution of royal cheating in social insects.


Asunto(s)
Hormigas/genética , Hormigas/fisiología , Evolución Biológica , Tamaño Corporal/fisiología , Aptitud Genética/fisiología , Jerarquia Social , Análisis de Varianza , Animales , Pesos y Medidas Corporales , Femenino , Aptitud Genética/genética , Genotipo , Repeticiones de Microsatélite/genética , Panamá , Reacción en Cadena de la Polimerasa , Análisis de Componente Principal , Estadísticas no Paramétricas , Alas de Animales/anatomía & histología
10.
Clin Radiol ; 67(6): 523-30, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22397729

RESUMEN

AIM: To report the results of a nationwide audit of the accuracy of magnetic resonance imaging (MRI) staging in uterine body cancer when staging myometrial invasion, cervical extension, and lymph node spread. MATERIALS AND METHODS: All UK radiology departments were invited to participate using a web-based tool for submitting anonymized data for a 12 month period. MRI staging was compared with histopathological staging using target accuracies of 85, 86, and 70% respectively. RESULTS: Of the departments performing MRI staging of endometrial cancer, 37/87 departments contributed. Targets for MRI staging were achieved for two of the three standards nationally with diagnostic accuracy for depth of myometrial invasion, 82%; for cervical extension, 90%; and for pelvic nodal involvement, 94%; the latter two being well above the targets. However, only 13/37 (35%) of individual centres met the target for assessing depth of myometrial invasion, 31/36 (86%) for cervical extension and 31/34 (91%) for pelvic nodal involvement. Statistical analysis demonstrated no significant difference for the use of intravenous contrast medium, but did show some evidence of increasing accuracy in assessment of depth of myometrial invasion with increasing caseload. CONCLUSION: Overall performance in the UK was good, with only the target for assessment of depth of myometrial invasion not being met. Inter-departmental variation was seen. One factor that may improve performance in assessment of myometrial invasion is a higher caseload. No other clear factor to improve performance were identified.


Asunto(s)
Imagen por Resonancia Magnética/normas , Auditoría Médica/métodos , Invasividad Neoplásica/patología , Neoplasias Uterinas/patología , Femenino , Humanos , Ganglios Linfáticos/patología , Metástasis Linfática , Miometrio/patología , Estadificación de Neoplasias , Reproducibilidad de los Resultados , Reino Unido , Neoplasias del Cuello Uterino/patología
11.
J Genet Couns ; 21(6): 862-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22825406

RESUMEN

The objective of this study was to explore how a parent-to-parent support network could impact parents of a child with a structural birth defect by specifically looking at parents' continued needs, aspects influencing their participation in support networks, and their recommendations. Structural birth defects occur in approximately 3 % of all infants, representing a significant public health issue. For many reasons, parents are uniquely qualified to provide support to each other. Data were collected retrospectively through a qualitative approach of focus groups or one-on-one interviews. Thirty one parents of infants registered in the Utah Birth Defect Network participated in the study. Three themes emerged, "current sources and inconsistencies in parent-to-parent-support," "aspects that influence participation in parent-to-parent network," and "recommendations for a parent-to-parent program." Health care providers need to be aware of the services and inform parents about these options. A statewide parent-to-parent network integrated into all hospitals would be a valuable resource to facilitate sharing of issues related to caring for an infant or child with a birth defect.


Asunto(s)
Anomalías Congénitas/psicología , Necesidades y Demandas de Servicios de Salud , Padres/psicología , Apoyo Social , Preescolar , Anomalías Congénitas/fisiopatología , Femenino , Humanos , Lactante , Masculino
12.
Br J Cancer ; 105(9): 1451-7, 2011 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-21915119

RESUMEN

BACKGROUND: Many of the established risk factors for breast cancer implicate circulating hormone levels in the aetiology of the disease. Increased levels of postmenopausal endogenous oestradiol (E2) have been found to increase the risk of breast cancer, but no such association has been confirmed in premenopausal women. We carried out a meta-analysis to summarise the available evidence in women before the menopause. METHODS: We identified seven prospective studies of premenopausal endogenous E2 and breast cancer risk, including 693 breast cancer cases. From each study we extracted odds ratios of breast cancer between quantiles of endogenous E2, or for unit or s.d. increases in (log transformed) E2, or (where odds ratios were unavailable) summary statistics for the distributions of E2 in breast cancer cases and unaffected controls. Estimates for a doubling of endogenous E2 were obtained from these extracted estimates, and random-effect meta-analysis was used to obtain a pooled estimate across the studies. RESULTS: Overall, we found weak evidence of a positive association between circulating E2 levels and the risk of breast cancer, with a doubling of E2 associated with an odds ratio of 1.10 (95% CI: 0.96, 1.27). CONCLUSION: Our findings are consistent with the hypothesis of a positive association between premenopausal endogenous E2 and breast cancer risk.


Asunto(s)
Neoplasias de la Mama/epidemiología , Estradiol/sangre , Adulto , Femenino , Humanos , Persona de Mediana Edad , Premenopausia , Estudios Prospectivos , Factores de Riesgo
13.
J Ethnopharmacol ; 267: 113609, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33242621

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Unravelling the anti-diabetic mechanism of action of L. leonurus at adipose, liver, muscle and pancreatic level. AIMS: To investigate the mechanism of action of an organic extract of L. leonurus and marrubiin at the gene level in adipose, liver and muscle tissues of an obese rat model and in a co-culture model. MATERIALS AND METHODS: Obese Wistar rats were fed a cafeteria diet for eight weeks, treated with an extract of L. Leonurus, marrubiin, sulfonylurea and aspirin for two weeks and the level of gene expression of selected markers were investigated across different tissues. The effects mediated by the different treatments were investigated in co-culture cell models involving 3T3-L1 (fat), Chang (liver), C2C12 (muscle) and INS-1 (pancreatic) cells under both normal and hyperglycemic conditions. RESULTS: L. leonurus extract mediated a significant increase in PPAR gamma, glucokinase, FAS and UCP2 gene expression in adipose tissue, whilst the opposite was observed in the liver. At the muscle level, a significant increase in FAS gene expression was observed relative to the obese control rats. Furthermore, the extract as well as marrubiin, modulated improvements in the adipokine profile. The co-culture models showed that the effect mediated by the extract was dependent on, the tissue type as well as the glycemic conditions. CONCLUSIONS: L. Leonurus extract as well as marrubiin exhibit anti-diabetic properties where the mechanism of action is mainly at the adipose tissue level. The increase in expression of the genes of interest mentioned above potentially play a protective role towards the liver and possibly towards the muscle tissues as well.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Comunicación Celular/efectos de los fármacos , Hipoglucemiantes/farmacología , Lamiaceae , Obesidad/tratamiento farmacológico , Extractos Vegetales/farmacología , Células 3T3 , Adipoquinas/genética , Adipoquinas/metabolismo , Tejido Adiposo/metabolismo , Animales , Técnicas de Cocultivo , Citocinas/genética , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación de la Expresión Génica , Hipoglucemiantes/aislamiento & purificación , Lamiaceae/química , Hígado/efectos de los fármacos , Hígado/metabolismo , Ratones , Músculo Esquelético/efectos de los fármacos , Obesidad/genética , Obesidad/metabolismo , Páncreas/efectos de los fármacos , Páncreas/metabolismo , Extractos Vegetales/aislamiento & purificación , Ratas Wistar , Transducción de Señal
14.
Mol Ecol ; 19(18): 4077-85, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20738784

RESUMEN

Although the intracellular bacterium Wolbachia is ubiquitous in insects, it has a unique relationship with New World ants on which particular bacterial strains have specialized. However, data are from distantly related hosts and detailed phylogenetic information which could reveal transmission dynamics are lacking. Here, we investigate host-Wolbachia relationships in the monophyletic fungus-growing ant tribe Attini, screening 23 species and using multilocus sequence typing to reliably identify Wolbachia strains. This technique reduces the significant problem of recombination seen using traditional single gene techniques. The relationship between Wolbachia and the fungus-growing ants appears complex and dynamic. There is evidence of co-cladogenesis, supporting vertical transmission; however, this is incomplete, demonstrating that horizontal transmission has also occurred. Importantly, the infection prevalence is frequently different between closely related taxa, with the Acromyrmex leaf-cutting ants appearing particularly prone to infection and there being no consistent relationship with any of the major life history transitions. We suggest that infection loss and horizontal transmission have driven epidemics or selective sweeps of Wolbachia, resulting in multiple gains and losses of infection across the fungus-growing ants.


Asunto(s)
Hormigas/microbiología , Filogenia , Wolbachia/genética , Animales , ADN Bacteriano/genética , Tipificación de Secuencias Multilocus , Especificidad de la Especie , Simbiosis , Wolbachia/clasificación
15.
Phys Rev Lett ; 105(2): 027207, 2010 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-20867739

RESUMEN

We report an inelastic neutron scattering study of the spin fluctuations in the nearly ferromagnetic element palladium. Dispersive over-damped collective magnetic excitations or "paramagnons" are observed up to 128 meV. We analyze our results in terms of a Moriya-Lonzarich-type spin-fluctuation model and estimate the contribution of the spin fluctuations to the low-temperature heat capacity. In spite of the paramagnon excitations being relatively strong, their relaxation rates are large. This leads to a small contribution to the low-temperature electronic specific heat.

16.
Int J Geriatr Psychiatry ; 25(11): 1119-26, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20084620

RESUMEN

AIM: To determine rates of cerebral atrophy in individuals with symptoms of memory loss but no objective cognitive impairment (SNCI) and their association with future cognitive decline. METHODS: Thirty-two SNCI subjects, 16 with mild cognitive impairment (MCI) and 27 control subjects had clinical assessment and magnetic resonance imaging at baseline and 1 year later. Rates of whole brain atrophy (WBA), hippocampal atrophy (HA) and ventricular enlargement (VE) were measured. Our outcome was clinical diagnosis at 2 years after entry into the study. RESULTS: The MCI group had greater rates of WBA, HA and VE than both controls and SNCI subjects. As a group SNCI subjects did not have significantly greater rates of atrophy than the controls. However, SNCI subjects who progressed to MCI or dementia had increased rates of atrophy compared with those who remained stable. DISCUSSION: Individuals with memory complaints but no objective memory deficits, who progress to MCI or dementia, have increased rates of cerebral atrophy.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/patología , Encéfalo/patología , Trastornos del Conocimiento/patología , Trastornos de la Memoria/patología , Anciano , Enfermedad de Alzheimer/psicología , Atrofia/patología , Trastornos del Conocimiento/diagnóstico , Trastornos del Conocimiento/psicología , Estudios de Cohortes , Diagnóstico Precoz , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores de Riesgo
17.
J Phys Condens Matter ; 32(37): 374007, 2020 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-32050188

RESUMEN

It is well established that in the low-temperature limit, the two-dimensional quantum Heisenberg antiferromagnet on a square lattice (2DQHAFSL) exhibits an anomaly in its spectrum at short-wavelengths on the zone-boundary. In the vicinity of the [Formula: see text] point the pole in the one-magnon response exhibits a downward dispersion, is heavily damped and attenuated, giving way to an isotropic continuum of excitations extending to high energies. The origin of the anomaly and the presence of the continuum are of current theoretical interest, with suggestions focused around the idea that the latter evidences the existence of spinons in a two-dimensional system. Here we present the results of neutron inelastic scattering experiments and Quantum Monte Carlo calculations on the metallo-organic compound Cu(DCOO)[Formula: see text]D2O (CFTD), an excellent physical realisation of the 2DQHAFSL, designed to investigate how the anomaly at [Formula: see text] evolves up to finite temperatures [Formula: see text]. Our data reveal that on warming the anomaly survives the loss of long-range, three-dimensional order, and that it is thus a robust feature of the two-dimensional system. With further increase of temperature the zone-boundary response gradually softens and broadens, washing out the [Formula: see text] anomaly. This is confirmed by a comparison of our data with the results of finite-temperature Quantum Monte Carlo simulations where the two are found to be in good accord. In the vicinity of the antiferromagnetic zone centre, there was no significant softening of the magnetic excitations over the range of temperatures investigated.

18.
Neuropsychologia ; 46(6): 1732-7, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18395233

RESUMEN

Alzheimer's disease (AD) is associated with excess whole brain volume loss, and progressive cognitive impairment. We aimed to study the extent to which these two potential biomarkers of AD progression are correlated. Forty-six patients with sporadic AD were tested with a neuropsychometric battery including test of verbal and visual memory, vocabulary, arithmetic, naming, visuoperceptual skills and reasoning at two time-points, approximately 1 year apart; annualised rates of change for each test were calculated. Each subject also attended for up to twelve T1-weighted volumetric MRI scans at fixed intervals over a 2-year period. For each individual all possible scan-pairs were positionally registered, and whole brain atrophy rates were calculated using the brain boundary shift integral. Linear mixed models were used to investigate associations between atrophy rate and coincident change in each neuropsychometric score. Each model estimated the effect of a unit change in score, plus the additional effect of a fall to floor, after adjusting for baseline levels. 467 MRI scans were performed, permitting 2199 individual measures of change to be made. The model-derived mean atrophy rate was 2.23% per year with a between-subject SD of 0.99% per year. Increasing atrophy rate was significantly associated with rate of change in a number of non-memory based neuropsychological scores, with the strongest association seen with longitudinal change in matrix reasoning (p=0.004). These results provide further evidence that cerebral atrophy is a clinically relevant marker of AD progression. This methodology whereby data from patients falling to floor on a given test may be included and accounted for, rather than discarded, may find broader application in clinical studies incorporating neuropsychometric outcomes.


Asunto(s)
Enfermedad de Alzheimer/patología , Mapeo Encefálico , Encéfalo/patología , Pruebas Neuropsicológicas , Anciano , Enfermedad de Alzheimer/complicaciones , Atrofia/etiología , Atrofia/patología , Progresión de la Enfermedad , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Estadística como Asunto
19.
Peptides ; 29(8): 1305-11, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18436344

RESUMEN

Six selected diketopiperazines, cyclo(Gly-Val), cyclo(Gly-D-Val), cyclo(Gly-Leu), cyclo(Gly-Ile), cyclo(Phe-Cys) and cyclo(Tyr-Cys), were synthesized via various synthetic routes. Their potential to inhibit cancer cell growth in HT-29, HeLa and MCF-7 cells was determined. Cyclo(Tyr-Cys) caused the greatest inhibition in cervical carcinoma cells with near equivalent activity against HT-29 and MCF-7 cells. The other cyclic dipeptides tested were effective in the inhibition of colon, cervical and breast carcinoma cells, respectively, but the percentage inhibition was lower than for cyclo(Tyr-Cys).


Asunto(s)
Antineoplásicos/síntesis química , Carcinoma/tratamiento farmacológico , Dicetopiperazinas/síntesis química , Neoplasias/tratamiento farmacológico , Péptidos Cíclicos/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Dicetopiperazinas/química , Dicetopiperazinas/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Células HT29 , Células HeLa , Humanos , Espectrometría de Masas , Microscopía Electrónica de Rastreo , Estructura Molecular , Péptidos Cíclicos/química , Péptidos Cíclicos/farmacología
20.
3 Biotech ; 8(10): 438, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30306007

RESUMEN

In vitro studies were conducted to determine the short-term cytotoxic and genotoxic effects of pure glyphosate and two glyphosate formulations (Roundup® and Wipeout®) at concentrations relevant to human exposure using whole blood (cytotoxicity) and various cancer cell lines (cytotoxicity and genotoxicity). Pure glyphosate (pure glyph) and Roundup® (Ro) showed similar non-monotonic toxicological profiles at low dose exposure (from 10 µg/ml), whereas Wipeout® (Wo) demonstrated a monotonic reduction in cell viability from a threshold concentration of 50 µg/ml, when tested in whole blood. We evaluated whether using various cancer cells (the estrogen-E2-responsive HEC1A, MCF7 and the estrogen-insensitive MDA-MB-231) exposed to moderate doses (75-500 µg/ml) would indicate varied toxicity and results indicated significant effects in the HEC1A cancer cells. A non-monotonic reduction in cell viability was observed in HEC1A exposed to pure glyph (75-500 µg/ml) and proliferative effects were observed after exposure to Wo (75, 125 and 250 µg/ml). Genotoxicity assessment (test concentration 500 µg/ml) demonstrated DNA damage in the HEC1A and MDA-MB-231 cells. Adjuvants and/or glyphosate impurities were potential contributing factors of toxicity based on the differential toxicities displayed by Ro and Wo in human whole blood and the HEC1A cells. This study contributes to the existing knowledge about in vitro exposure to moderate concentrations of glyphosate or glyphosate formulations at cytotoxic and genotoxic levels. In addition, a suggestion on the relevance of the estrogen receptor status of the cell lines used is provided, leading to the need to further investigate a potential endocrine disruptive role.

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