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1.
Int J Mol Sci ; 25(14)2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39063162

RESUMO

Little resistance to the pea weevil insect pest (Bruchus pisorum) is available in pea (Pisum sativum) cultivars, highlighting the need to search for sources of resistance in Pisum germplasm and to decipher the genetic basis of resistance. To address this need, we screened the response to pea weevil in a Pisum germplasm collection (324 accession, previously genotyped) under field conditions over four environments. Significant variation for weevil seed infestation (SI) was identified, with resistance being frequent in P. fulvum, followed by P. sativum ssp. elatius, P. abyssinicum, and P. sativum ssp. humile. SI tended to be higher in accessions with lighter seed color. SI was also affected by environmental factors, being favored by high humidity during flowering and hampered by warm winter temperatures and high evapotranspiration during and after flowering. Merging the phenotypic and genotypic data allowed genome-wide association studies (GWAS) yielding 73 markers significantly associated with SI. Through the GWAS models, 23 candidate genes were found associated with weevil resistance, highlighting the interest of five genes located on chromosome 6. These included gene 127136761 encoding squalene epoxidase; gene 127091639 encoding a transcription factor MYB SRM1; gene 127097033 encoding a 60S ribosomal protein L14; gene 127092211, encoding a BolA-like family protein, which, interestingly, was located within QTL BpLD.I, earlier described as conferring resistance to weevil in pea; and gene 127096593 encoding a methyltransferase. These associated genes offer valuable potential for developing pea varieties resistant to Bruchus spp. and efficient utilization of genomic resources through marker-assisted selection (MAS).


Assuntos
Estudo de Associação Genômica Ampla , Pisum sativum , Gorgulhos , Animais , Gorgulhos/genética , Gorgulhos/fisiologia , Pisum sativum/genética , Pisum sativum/parasitologia , Marcadores Genéticos , Resistência à Doença/genética , Doenças das Plantas/parasitologia , Doenças das Plantas/genética , Genótipo , Fenótipo , Locos de Características Quantitativas , Polimorfismo de Nucleotídeo Único
2.
Nanotechnology ; 31(19): 195602, 2020 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31931487

RESUMO

All-dielectric photonics is a rapidly developing field of optics and material science. The main interest at visible and near-infrared frequencies is light management using high-refractive-index Mie-resonant dielectric particles. Most work in this area of research focuses on exploiting Si-based particles. Here, we study monocrystalline Mie-resonant particles made of Ge-rich SiGe alloys with refractive index higher than that of Si. These islands are formed via solid state dewetting of SiGe flat layers by using two different processes: (i) dewetting of monocrystalline SiGe layers (60%-80% Ge content) obtained via Ge condensation of SiGe on silicon on insulator; and (ii) dewetting of a SiGe layer deposited via molecular beam epitaxy on silicon on insulator and ex situ Ge condensation, forming a Ge-rich shell surrounding a SiGe-core. Using high-spatial-resolution Raman microscopy we monitor Ge content x and strain ϵ of flat layers and SiGe-islands. We observe strain relaxation associated with formation of trading dislocations in the SiGe islands compared to the starting SiGe layers, as confirmed by TEM images. For initial high Ge concentration in the flat layers, the corresponding Ge content in the dewetted islands is lower, owing to diffusion of Si atoms from Si or SiO2 into SiGe islands. The Ge content also varies from particle to particle on the same sample. Size and shape of the dewetted particles depend on the fabrication process: thicker initial SiGe layers lead to larger particles. Samples with narrow island size distribution display rather sharp Mie resonances in the 1000-2500 nm spectral range. Larger islands display Mie resonances at longer wavelength. Positions of the resonances are in agreement with the theoretical calculations in the discrete dipole approximation.

3.
Opt Express ; 24(18): A1201-9, 2016 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-27607723

RESUMO

The fast and computationally inexpensive Modified Transfer Matrix Method (MTM) is employed to simulate the optical response of kesterite Cu2ZnSnSe4 solar cells. This method can partially take into account the scattering effects due to roughness at the interfaces between the layers of the stack. We analyzed the optical behavior of the whole cell structure by varying the thickness of the TCO layer (iZnO + ITO) between 50 and 1200 nm and the buffer CdS layer between 0 and 100 nm. We propose optimal combinations of the TCO/CdS thicknesses that can locally maximize the device photocurrent. We provide experimental data that qualitatively confirm our theoretical predictions.

4.
Small Methods ; 8(1): e2300930, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37806771

RESUMO

With the rise of engineered living materials (ELMs) as innovative, sustainable and smart systems for diverse engineering and biological applications, global interest in advancing ELMs is on the rise. Graphene-based nanostructures can serve as effective tools to fabricate ELMs. By using graphene-based materials as building units and microorganisms as the designers of the end materials, next-generation ELMs can be engineered with the structural properties of graphene-based materials and the inherent properties of the microorganisms. However, some challenges need to be addressed to fully take advantage of graphene-based nanostructures for the design of next-generation ELMs. This work covers the latest advances in the fabrication and application of graphene-based ELMs. Fabrication strategies of graphene-based ELMs are first categorized, followed by a systematic investigation of the advantages and disadvantages within each category. Next, the potential applications of graphene-based ELMs are covered. Moreover, the challenges associated with fabrication of next-generation graphene-based ELMs are identified and discussed. Based on a comprehensive overview of the literature, the primary challenge limiting the integration of graphene-based nanostructures in ELMs is nanotoxicity arising from synthetic and structural parameters. Finally, we present possible design principles to potentially address these challenges.


Assuntos
Grafite , Nanoestruturas , Grafite/toxicidade , Grafite/química , Nanoestruturas/efeitos adversos , Nanoestruturas/química
5.
Clin Rehabil ; 27(8): 681-5, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23411793

RESUMO

OBJECTIVE: To determine whether the efficacy of botulinum toxin type A in chronic plantar fasciitis was maintained for more than six months after treatment. DESIGN: Observational follow-up study. SUBJECTS: Twenty-four patients who received botulinum toxin type A injection in a previous randomized study of chronic plantar fasciitis (active treatment group) and who presented a benefit one month after treatment. METHODS: A visual analogue scale for pain and the Foot Health Status Questionnaire were used to re-evaluate results 12 months after the botulinum toxin injection. No further injections of botulinum toxin had been administered during the follow-up period. Patients were also asked to give a subjective assessment of treatment outcome. RESULTS: At 12 months, compared with the six-month evaluation, there was a further improvement in foot pain measured using the visual analogue scale, though this did not reach significance (1.78 at 6 months versus 1.22 at 12 months; P = 0.142). However, there were significant improvements in two domains of Foot Health Status Questionnaire: foot pain (91.11 at 6 months versus 80.00 at 12 months; P = 0.001) and foot function (96.19 at 6 months versus 89.38 at 12 months; P = 0.047). There was a small, non-significant deterioration in the shoe and foot health domains. Satisfaction with the outcome was good or very good in the large majority of patients. CONCLUSIONS: In patients with chronic plantar fasciitis, the positive effect detected six months after treatment with botulinum toxin type A was maintained at 12 months and there was a further improvement in pain and foot function.


Assuntos
Toxinas Botulínicas Tipo A/uso terapêutico , Fasciíte Plantar/tratamento farmacológico , Dor/tratamento farmacológico , Toxinas Botulínicas Tipo A/administração & dosagem , Doença Crônica , Feminino , Seguimentos , Humanos , Injeções , Masculino , Pessoa de Meia-Idade , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/uso terapêutico , Medição da Dor , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
6.
Clin Rehabil ; 26(7): 594-606, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22144721

RESUMO

OBJECTIVE: To determine the efficacy of botulinum toxin type A in chronic plantar fasciitis compared to the local injection of a corticosteroid plus local anaesthetic. METHODS: Patients with a clinical diagnosis of plantar fasciitis made at least six months earlier were selected to enter a randomized, single-blind study of treatment with injections of botulinum toxin type A or corticosteroid. There were 28 patients in each treatment group. Patients were evaluated at one month using the Foot Health Square Questionnaire and those with no clinical response subsequently received a second injection with the drug of the other arm of the study, creating two new treatment groups. Re-evaluation was performed at six months. RESULTS: One month after injection there was a clear clinical improvement in both treatment groups but it was greater in the botulinum toxin group, with a significant difference for the pain item (P = 0.069), though not in other items. At six months, patients treated with botulinum toxin type A had continued to improve in all items, whereas the corticosteroid group lost part of the improvement achieved at one month (improvement with botulinum toxin vs. corticosteroid: pain 19.10/-6.84 (P = 0.001), function 16.00/-8.80 (P < 0.001), footwear 13.48/-7.95 (P = 0.004), self-perceived foot health 25.44/-5.41 (P < 0.001). CONCLUSION: Botulinum toxin type A should be considered for the treatment of chronic plantar fasciitis in view of the improvement found at one month, and particularly at six months, when this treatment clearly has better results than corticosteroid injections. Further studies with larger samples are necessary to confirm these results.


Assuntos
Corticosteroides/administração & dosagem , Toxinas Botulínicas Tipo A/administração & dosagem , Fasciíte Plantar/tratamento farmacológico , Dor/tratamento farmacológico , Corticosteroides/uso terapêutico , Toxinas Botulínicas Tipo A/uso terapêutico , Feminino , Humanos , Injeções Intramusculares/métodos , Masculino , Pessoa de Meia-Idade , Fármacos Neuromusculares/administração & dosagem , Fármacos Neuromusculares/uso terapêutico , Método Simples-Cego , Tempo , Resultado do Tratamento
7.
J Surg Case Rep ; 2021(3): rjab056, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33815750

RESUMO

There are but a handful of reported brachial artery aneurysms, the majority of which are pseudoaneurysms or false aneurysms caused by trauma or fistula creation. True or primary brachial artery aneurysms are even more rare, and if they occur, they often do so in isolation. In this case report, we discuss the interesting finding of a large primary brachial aneurysm together with an adjacent aneurysmal basilic vein identified intra-operatively. This presentation was 21 years after the renal transplant and ligation of an arteriovenous fistula in that same arm. It is noteworthy that the fistula was in the forearm and far away from the site of the untouched brachial area.

8.
Front Neurol ; 10: 1168, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31787922

RESUMO

Mitochondrial dysfunction has been recognized as a key player in neurodegenerative diseases, including Alzheimer's disease (AD) and Niemann-Pick type C (NPC) disease. While the pathogenesis of both diseases is different, disruption of intracellular cholesterol trafficking has emerged as a common feature of both AD and NPC disease. Nutritional or genetic mitochondrial cholesterol accumulation sensitizes neurons to Aß-mediated neurotoxicity in vitro and promotes cognitive decline in AD models. In addition to the primary accumulation of cholesterol and sphingolipids in lysosomes, NPC disease is also characterized by an increase in mitochondrial cholesterol levels in affected organs, predominantly in brain and liver. In both diseases, mitochondrial cholesterol accumulation disrupts membrane physical properties and restricts the transport of glutathione into mitochondrial matrix, thus impairing the mitochondrial antioxidant defense strategy. The underlying mechanisms leading to mitochondrial cholesterol accumulation in AD and NPC diseases are not fully understood. In the present manuscript, we discuss evidence for the potential role of StARD1 in promoting the trafficking of cholesterol to mitochondria in AD and NPC, whose upregulation involves an endoplasmic reticulum stress and a decrease in acid ceramidase expression, respectively. These findings imply that targeting StARD1 or boosting the mitochondrial antioxidant defense may emerge as a promising approach for both AD and NPC disease.

9.
R Soc Open Sci ; 6(6): 190420, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31312500

RESUMO

Smoking is associated with shorter leucocyte telomere length (LTL), a biomarker of increased morbidity and reduced longevity. This association is widely interpreted as evidence that smoking causes accelerated LTL attrition in adulthood, but the evidence for this is inconsistent. We analysed the association between smoking and LTL dynamics in 18 longitudinal cohorts. The dataset included data from 12 579 adults (4678 current smokers and 7901 non-smokers) over a mean follow-up interval of 8.6 years. Meta-analysis confirmed a cross-sectional difference in LTL between smokers and non-smokers, with mean LTL 84.61 bp shorter in smokers (95% CI: 22.62 to 146.61). However, LTL attrition was only 0.51 bp yr-1 faster in smokers than in non-smokers (95% CI: -2.09 to 1.08), a difference that equates to only 1.32% of the estimated age-related loss of 38.33 bp yr-1. Assuming a linear effect of smoking, 167 years of smoking would be required to generate the observed cross-sectional difference in LTL. Therefore, the difference in LTL between smokers and non-smokers is extremely unlikely to be explained by a linear, causal effect of smoking. Selective adoption, whereby individuals with short telomeres are more likely to start smoking, needs to be considered as a more plausible explanation for the observed pattern of telomere dynamics.

10.
Aging Cell ; 4(6): 287-90, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16300480

RESUMO

Cross-sectional studies have repeatedly suggested peripheral blood monocyte telomere length as a biomarker of aging. To test this suggestion in a large population-based follow-up study of the oldest old, we measured telomere length at baseline in 598 participants of the Leiden 85-plus Study (mean age at baseline 89.8 years). We also obtained second telomere measurements from 81 participants after an average time span of between 3.9 and 12.9 years. Telomere length at baseline was not predictive for mortality (P > 0.40 for all-cause, cardiovascular causes, cancer or infectious diseases, Cox regression for gender-adjusted tertiles of telomere length) or for the incidence of dementia (P = 0.78). Longitudinally, telomere length was highly unstable in a large fraction of participants. We conclude that blood monocyte telomere length is not a predictive indicator for age-related morbidity and mortality at ages over 85 years, possibly because of a high degree of telomere length instability in this group.


Assuntos
Envelhecimento/fisiologia , Telômero/ultraestrutura , Idoso de 80 Anos ou mais , Biomarcadores , Estudos Transversais , Feminino , Seguimentos , Humanos , Masculino , Monócitos/citologia , Morbidade , Mortalidade , Análise de Sobrevida
11.
EBioMedicine ; 2(10): 1549-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26629551

RESUMO

To determine the most important drivers of successful ageing at extreme old age, we combined community-based prospective cohorts: Tokyo Oldest Old Survey on Total Health (TOOTH), Tokyo Centenarians Study (TCS) and Japanese Semi-Supercentenarians Study (JSS) comprising 1554 individuals including 684 centenarians and (semi-)supercentenarians, 167 pairs of centenarian offspring and spouses, and 536 community-living very old (85 to 99 years). We combined z scores from multiple biomarkers to describe haematopoiesis, inflammation, lipid and glucose metabolism, liver function, renal function, and cellular senescence domains. In Cox proportional hazard models, inflammation predicted all-cause mortality with hazard ratios (95% CI) 1.89 (1.21 to 2.95) and 1.36 (1.05 to 1.78) in the very old and (semi-)supercentenarians, respectively. In linear forward stepwise models, inflammation predicted capability (10.8% variance explained) and cognition (8(.)6% variance explained) in (semi-)supercentenarians better than chronologic age or gender. The inflammation score was also lower in centenarian offspring compared to age-matched controls with Δ (95% CI) = - 0.795 (- 1.436 to - 0.154). Centenarians and their offspring were able to maintain long telomeres, but telomere length was not a predictor of successful ageing in centenarians and semi-supercentenarians. We conclude that inflammation is an important malleable driver of ageing up to extreme old age in humans.


Assuntos
Envelhecimento/genética , Inflamação/genética , Inflamação/mortalidade , Telômero/genética , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/metabolismo , Biomarcadores , Causas de Morte , Senescência Celular/genética , Feminino , Humanos , Imunossenescência/genética , Inflamação/epidemiologia , Inflamação/metabolismo , Estimativa de Kaplan-Meier , Longevidade/genética , Estudos Longitudinais , Masculino , Morbidade
12.
Int J Epidemiol ; 44(5): 1673-83, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25239152

RESUMO

BACKGROUND: Telomere length is a putative biomarker of ageing, morbidity and mortality. Its application is hampered by lack of widely applicable reference ranges and uncertainty regarding the present limits of measurement reproducibility within and between laboratories. METHODS: We instigated an international collaborative study of telomere length assessment: 10 different laboratories, employing 3 different techniques [Southern blotting, single telomere length analysis (STELA) and real-time quantitative PCR (qPCR)] performed two rounds of fully blinded measurements on 10 human DNA samples per round to enable unbiased assessment of intra- and inter-batch variation between laboratories and techniques. RESULTS: Absolute results from different laboratories differed widely and could thus not be compared directly, but rankings of relative telomere lengths were highly correlated (correlation coefficients of 0.63-0.99). Intra-technique correlations were similar for Southern blotting and qPCR and were stronger than inter-technique ones. However, inter-laboratory coefficients of variation (CVs) averaged about 10% for Southern blotting and STELA and more than 20% for qPCR. This difference was compensated for by a higher dynamic range for the qPCR method as shown by equal variance after z-scoring. Technical variation per laboratory, measured as median of intra- and inter-batch CVs, ranged from 1.4% to 9.5%, with differences between laboratories only marginally significant (P = 0.06). Gel-based and PCR-based techniques were not different in accuracy. CONCLUSIONS: Intra- and inter-laboratory technical variation severely limits the usefulness of data pooling and excludes sharing of reference ranges between laboratories. We propose to establish a common set of physical telomere length standards to improve comparability of telomere length estimates between laboratories.


Assuntos
Envelhecimento/genética , DNA/genética , Telômero/genética , Biomarcadores , Southern Blotting , Humanos , Cooperação Internacional , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes
13.
Biol Psychiatry ; 54(11): 1222-33, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14643090

RESUMO

BACKGROUND: The etiology of dementia that occurs in patients with schizophrenia is not well understood. Nicotinic acetylcholine receptors have been implicated in cognitive function, and deficits in these receptors have been reported in schizophrenia. METHODS: The present study investigates possible associations of nicotinic receptor subunit expression in the dorsal lateral prefrontal cortex, an area known to be affected in schizophrenia, and dementia rating. RESULTS: alpha7 immunoreactivity was reduced by 20% to 28% and [(3)H]epibatidine binding was increased twofold in groups of patients with schizophrenia compared to normal control subjects matched for age, postmortem delay, and low levels of brain nicotine and cotinine. In contrast, no significant differences in alpha4, alpha3, or beta2 immunoreactivity or alpha7 messenger RNA expression were observed in schizophrenia patients compared with control subject values. Clinical dementia ratings in patients with schizophrenia were correlated with neither [(3)H]epibatidine binding nor nicotinic receptor subunit expression. CONCLUSIONS: These data indicate no relationship between the trend for reduced neocortical alpha7 subunit protein expression in schizophrenia and dementia. Further investigations are required to establish whether the reduction in alpha7 protein in the dorsal lateral prefrontal cortex is associated with clinical features other than dementia in schizophrenia.


Assuntos
Demência/metabolismo , Córtex Pré-Frontal/metabolismo , Receptores Nicotínicos/biossíntese , Esquizofrenia/metabolismo , Idoso , Idoso de 80 Anos ou mais , Compostos Bicíclicos Heterocíclicos com Pontes/metabolismo , Estudos de Casos e Controles , Cotinina/metabolismo , Demência/complicações , Demência/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nicotina/metabolismo , Escalas de Graduação Psiquiátrica , Piridinas/metabolismo , RNA Mensageiro/biossíntese , Ensaio Radioligante , Esquizofrenia/complicações , Esquizofrenia/diagnóstico , Índice de Gravidade de Doença , Fumar
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