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1.
Neuroendocrinology ; 114(4): 348-355, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38169458

RESUMO

INTRODUCTION: Hyperthyroidism, characterized by excessive thyroid hormone production, is a common endocrine disorder that affects various physiological processes, including brain function. Recent advancements in neuroimaging techniques have enabled researchers to investigate structural alterations in the brain associated with hyperthyroidism. This study aimed to examine regional cortical thickness and cortical volume differences across the brain between hyperthyroid patients and control subjects. METHODS: We examined localized cortical thicknesses and volumes in 34 hyperthyroid patients and 35 control subjects with high-resolution T1-weighted images using FreeSurfer software and assessed group differences with analysis of covariance (covariates: age, sex, education, and total intracranial volume). Spearman and partial correlations were performed between clinical variables and cortical thicknesses/volumes and between neuropsychological scores and cortical thicknesses/volumes, respectively. RESULTS: Hyperthyroid patients exhibited significantly increased cortical thickness in bilateral superior temporal and superior frontal gyri, along with higher cortical volumes in various regions, including the right superior temporal gyrus, right superior parietal gyrus, right rostral and caudal middle frontal gyrus, and left superior frontal gyrus. Notably, thyroid hormones (fT3, fT4) correlated positively with cortical thicknesses and volumes in the superior temporal gyrus and superior frontal gyrus. Additionally, recognition memory scores negatively correlated with the right superior temporal gyrus and right superior frontal gyrus cortical thickness. CONCLUSION: The observed cortical thickening and increased cortical volume in specific brain areas provide new insights into the pathophysiological mechanism associated with brain impairment in hyperthyroidism.


Assuntos
Substância Cinzenta , Hipertireoidismo , Humanos , Substância Cinzenta/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Encéfalo , Córtex Pré-Frontal
2.
Alzheimers Dement ; 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38946683

RESUMO

BACKGROUND: Evidence for the effect of early menopause on cognition among older women is not consistent and is scant among the Indian population. METHODS: We aimed to examine the effect of early menopause (≤45 years) on cognitive performance and brain morphology among older dementia-free females of the TLSA cohort using a multiple linear regression analysis. RESULTS: In a sample of 528 women, 144 (27%) had early menopause. The linear regression analysis showed that women with early menopause performed poorly in cognition and had lesser total gray matter volume [ß = -11973.94, p = 0.033], left middle frontal [ß = -353.14, p = 0.033], and left superior frontal [ß = -460.97, p < 0.026] volume. CONCLUSION: Dementia-free women with early menopause had poorer cognition, lower total gray matter, and frontal lobe. More research is needed to explore the link between earlier menopause and cognitive decline and develop ways to address it. HIGHLIGHTS: Evidence on the effect of early menopause on brain morphology is inconsistent and scant in low and middle-income countries, such as India. In a cohort of dementia-free individuals in urban Bangalore, we observed that participants with early menopause had significantly lower cognitive performance and lower total gray matter and frontal lobe volume. We recommend increasing awareness of this fact among the medical community and the general public. There is an urgent need to explore the underlying biological mechanism and to discover effective interventions to mitigate the effect.

3.
Inorg Chem ; 61(9): 3811-3815, 2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35192343

RESUMO

The deprotonation of acyclic palladium amidine chloride (1) with potassium tert-butoxide in tetrahydrofuran results in palladium bis(formamidinate) (2). 2 undergoes a nucleophilic addition reaction with acetonitrile in the presence of PdCl2 or Pd(OAc)2 (OAc = acetate) to give dinuclear cyclic six-membered (triazapentadiene)palladium complexes (4a and 4b). These compounds are also prepared from cyclic six-membered (tap)PdCl2 (5; tap = triazapentadiene) or formamidinium salts (6a-6c) with Pd(OAc)2/NaOAc in acetonitrile, whereas the direct reaction of 2 with acetonitrile or acrylonitrile resulted in palladium black or an acyclic C-N-coupled product (3). A comparison of structure 4 from 2 suggests a possible intermediate dinuclear palladium complex whose structure was identified through theoretical calculations. Further, Suzuki-Miyaura cross-coupling reactions were carried out under different solvents notably in an ethanol/water medium at room temperature.

4.
Mol Biol Rep ; 49(8): 8025-8035, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35294703

RESUMO

Myo-inositol is one of the most abundant form of inositol. The myo-inositol (MI) serves as substrate to diverse biosynthesis pathways and hence it is conserved across life forms. The biosynthesis of MI is well studied in animals. Beyond biosynthesis pathway, implications of MI pathway and enzymes hold potential implications in plant physiology and crop improvement. Myo-inositol oxygenase (MIOX) enzyme catabolize MI into D-glucuronic acid (D-GlcUA). The MIOX enzyme family is well studied across few plants. More recently, the MI associated pathway's crosstalk with other important biosynthesis and stress responsive pathways in plants has drawn attention. The overall outcome from different plant species studied so far are very suggestive that MI derivatives and associated pathways could open new directions to explore stress responsive novel metabolic networks. There are evidences for upregulation of MI metabolic pathway genes, specially MIOX under different stress condition. We also found MIOX genes getting differentially expressed according to developmental and stress signals in Arabidopsis and wheat. In this review we try to highlight the missing links and put forward a tailored view over myo-inositol oxidation pathway and MIOX proteins.


Assuntos
Arabidopsis , Inositol Oxigenase , Animais , Arabidopsis/metabolismo , Vias Biossintéticas , Inositol/metabolismo , Inositol Oxigenase/genética , Inositol Oxigenase/metabolismo , Oxirredução
5.
BMC Genomics ; 22(1): 289, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33882825

RESUMO

BACKGROUND: Chickpea, pigeonpea, and groundnut are the primary legume crops of semi-arid tropics (SAT) and their global productivity is severely affected by drought stress. The plant-specific NAC (NAM - no apical meristem, ATAF - Arabidopsis transcription activation factor, and CUC - cup-shaped cotyledon) transcription factor family is known to be involved in majority of abiotic stresses, especially in the drought stress tolerance mechanism. Despite the knowledge available regarding NAC function, not much information is available on NAC genes in SAT legume crops. RESULTS: In this study, genome-wide NAC proteins - 72, 96, and 166 have been identified from the genomes of chickpea, pigeonpea, and groundnut, respectively, and later grouped into 10 clusters in chickpea and pigeonpea, while 12 clusters in groundnut. Phylogeny with well-known stress-responsive NACs in Arabidopsis thaliana, Oryza sativa (rice), Medicago truncatula, and Glycine max (soybean) enabled prediction of putative stress-responsive NACs in chickpea (22), pigeonpea (31), and groundnut (33). Transcriptome data revealed putative stress-responsive NACs at various developmental stages that showed differential expression patterns in the different tissues studied. Quantitative real-time PCR (qRT-PCR) was performed to validate the expression patterns of selected stress-responsive, Ca_NAC (Cicer arietinum - 14), Cc_NAC (Cajanus cajan - 15), and Ah_NAC (Arachis hypogaea - 14) genes using drought-stressed and well-watered root tissues from two contrasting drought-responsive genotypes of each of the three legumes. Based on expression analysis, Ca_06899, Ca_18090, Ca_22941, Ca_04337, Ca_04069, Ca_04233, Ca_12660, Ca_16379, Ca_16946, and Ca_21186; Cc_26125, Cc_43030, Cc_43785, Cc_43786, Cc_22429, and Cc_22430; Ah_ann1.G1V3KR.2, Ah_ann1.MI72XM.2, Ah_ann1.V0X4SV.1, Ah_ann1.FU1JML.2, and Ah_ann1.8AKD3R.1 were identified as potential drought stress-responsive candidate genes. CONCLUSION: As NAC genes are known to play role in several physiological and biological activities, a more comprehensive study on genome-wide identification and expression analyses of the NAC proteins have been carried out in chickpea, pigeonpea and groundnut. We have identified a total of 21 potential drought-responsive NAC genes in these legumes. These genes displayed correlation between gene expression, transcriptional regulation, and better tolerance against drought. The identified candidate genes, after validation, may serve as a useful resource for molecular breeding for drought tolerance in the SAT legume crops.


Assuntos
Cajanus , Cicer , Fabaceae , Cajanus/genética , Cicer/genética , Produtos Agrícolas/metabolismo , Secas , Fabaceae/genética , Fabaceae/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse Fisiológico/genética
6.
Funct Integr Genomics ; 21(3-4): 313-330, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34013486

RESUMO

Beyond the most crucial roles of RNA molecules as a messenger, ribosomal, and transfer RNAs, the regulatory role of many non-coding RNAs (ncRNAs) in plant biology has been recognized. ncRNAs act as riboregulators by recognizing specific nucleic acid targets through homologous sequence interactions to regulate plant growth, development, and stress responses. Regulatory ncRNAs, ranging from small to long ncRNAs (lncRNAs), exert their control over a vast array of biological processes. Based on the mode of biogenesis and their function, ncRNAs evolved into different forms that include microRNAs (miRNAs), small interfering RNAs (siRNAs), miRNA variants (isomiRs), lncRNAs, circular RNAs (circRNAs), and derived ncRNAs. This article explains the different classes of ncRNAs and their role in plant development and stress responses. Furthermore, the applications of regulatory ncRNAs in crop improvement, targeting agriculturally important traits, have been discussed.


Assuntos
Plantas , RNA não Traduzido , MicroRNAs/genética , Plantas/genética , RNA Longo não Codificante , RNA Interferente Pequeno , RNA não Traduzido/genética
7.
J Plant Res ; 134(3): 475-495, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33616799

RESUMO

Climate change, malnutrition, and food insecurity are the inevitable challenges being faced by the agriculture sector today. Plants are susceptible to extreme temperatures during the crucial phases of flowering and seed development, and elevated carbon levels also lead to yield losses. Productivity is also affected by floods and droughts. Therefore, increasing plant yield and stress tolerance are the priorities to be met through novel biotechnological interventions. The contributions of NAC genes towards enhancing plant survivability under stress is well known. Here we focus on the potential of NAC genes in the regulation of abiotic stress tolerance, secondary cell wall synthesis, lateral root development, yield potential, seed size and biomass, ROS signaling, leaf senescence, and programmed cell death. Once naturally tolerant candidate NAC genes have been identified, and the nature of their association with growth and fitness against multi-environmental stresses has been determined, they can be exploited for building inherent tolerance in future crops via transgenic technologies. An update on the latest developments is provided in this review, which summarizes the current understanding of the roles of NAC in the establishment of various stress-adaptive mechanisms in model and food crop plants.


Assuntos
Proteínas de Plantas , Fatores de Transcrição , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/metabolismo , Estresse Fisiológico , Fatores de Transcrição/genética
8.
Pediatr Res ; 87(1): 169-175, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31499515

RESUMO

BACKGROUND: Adolescents with single ventricle heart disease (SVHD) who have undergone the Fontan procedure show cognitive/memory deficits. Mammillary bodies are key brain sites that regulate memory; however, their integrity in SVHD is unclear. We evaluated mammillary body (MB) volumes and their associations with cognitive/memory scores in SVHD and controls. METHODS: Brain MRI data were collected from 63 adolescents (25 SVHD; 38 controls) using a 3.0-Tesla MRI scanner. Cognition and memory were assessed using Montreal Cognitive Assessment (MoCA) and Wide Range Assessment of Memory and Learning 2. MB volumes were calculated and compared between groups (ANCOVA, covariates: age, sex, and total brain volume [TBV]). Partial correlations and linear regression were performed to examine associations between volumes and cognitive scores (covariates: age, sex, and TBV). RESULTS: SVHD group showed significantly lower MoCA and WRAML2 scores over controls. MB volumes were significantly reduced in SVHD over controls. After controlling for age, sex, and TBV, MB volumes correlated with MoCA and delayed memory recall scores in SVHD and controls. CONCLUSION: Adolescents with SVHD show reduced MB volumes associated with cognitive/memory deficits. Potential mechanisms of volume losses may include developmental and/or hypoxic/ischemic-induced processes. Providers should screen for cognitive deficits and explore possible interventions to improve memory.


Assuntos
Cognição , Disfunção Cognitiva/diagnóstico por imagem , Técnica de Fontan/efeitos adversos , Imageamento por Ressonância Magnética , Corpos Mamilares/diagnóstico por imagem , Transtornos da Memória/diagnóstico por imagem , Memória , Coração Univentricular/cirurgia , Adolescente , Estudos de Casos e Controles , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Corpos Mamilares/fisiopatologia , Transtornos da Memória/fisiopatologia , Transtornos da Memória/psicologia , Testes Neuropsicológicos , Valor Preditivo dos Testes , Resultado do Tratamento
9.
Theor Appl Genet ; 132(6): 1607-1638, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30941464

RESUMO

KEY MESSAGE: We describe here the recent developments about the involvement of diverse stress-related proteins in sensing, signaling, and defending the cells in plants in response to drought or/and heat stress. In the current era of global climate drift, plant growth and productivity are often limited by various environmental stresses, especially drought and heat. Adaptation to abiotic stress is a multigenic process involving maintenance of homeostasis for proper survival under adverse environment. It has been widely observed that a series of proteins respond to heat and drought conditions at both transcriptional and translational levels. The proteins are involved in various signaling events, act as key transcriptional activators and saviors of plants under extreme environments. A detailed insight about the functional aspects of diverse stress-responsive proteins may assist in unraveling various stress resilience mechanisms in plants. Furthermore, by identifying the metabolic proteins associated with drought and heat tolerance, tolerant varieties can be produced through transgenic/recombinant technologies. A large number of regulatory and functional stress-associated proteins are reported to participate in response to heat and drought stresses, such as protein kinases, phosphatases, transcription factors, and late embryogenesis abundant proteins, dehydrins, osmotins, and heat shock proteins, which may be similar or unique to stress treatments. Few studies have revealed that cellular response to combined drought and heat stresses is distinctive, compared to their individual treatments. In this review, we would mainly focus on the new developments about various stress sensors and receptors, transcription factors, chaperones, and stress-associated proteins involved in drought or/and heat stresses, and their possible role in augmenting stress tolerance in crops.


Assuntos
Adaptação Fisiológica , Produtos Agrícolas , Secas , Regulação da Expressão Gênica de Plantas , Proteínas de Choque Térmico/metabolismo , Resposta ao Choque Térmico , Proteínas de Plantas/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Plantas/genética
10.
Neuroradiology ; 61(7): 811-824, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31041457

RESUMO

PURPOSE: Single ventricle heart disease (SVHD) patients show injury in brain sites that regulate autonomic, mood, and cognitive functions. However, the nature (acute or chronic changes) and extent of brain injury in SVHD are unclear. Our aim was to examine regional brain tissue damage in SVHD over controls using DTI-based mean diffusivity (MD), axial diffusivity (AD), radial diffusivity (RD), and fractional anisotropy (FA) procedures. METHODS: We collected two DTI series (3.0-T MRI), mood and cognitive data, from 27 SVHD and 35 control adolescents. Whole-brain MD, AD, RD, and FA maps were calculated from each series, realigned and averaged, normalized to a common space, smoothed, and compared between groups using ANCOVA (covariates, age and sex; false discovery rate, p < 0.05). Region-of-interest analyses were performed to calculate MD, AD, RD, and FA values for magnitude assessment between groups. RESULTS: SVHD patients showed impaired mood and cognitive functions over healthy adolescents. Multiple brain sites in SVHD showed increased MD values, including the insula, caudate, cingulate, hypothalamus, thalamus, medial prefrontal and frontal cortices, parahippocampal gyrus, hippocampus, precentral gyrus, amygdala, cerebellum, corpus callosum, basal forebrain, mammillary bodies, internal capsule, midbrain, fornix, and occipital, parietal, and temporal cortices, indicating chronic tissue changes. Similar areas showed either increased AD or RD values, with RD changes more enhanced over AD in SVHD compared to controls. Few brain regions emerged with increased or decreased FA values in SVHD patients over controls. CONCLUSION: SVHD adolescents, more than a decade from their last surgical procedure, show widespread brain abnormalities in autonomic, mood, and cognitive regulatory areas. These findings indicate that brain injury is in a chronic stage in SVHD with predominantly myelin changes that may result from previous hypoxia/ischemia- or developmental-induced processes.


Assuntos
Encefalopatias/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Técnica de Fontan , Adolescente , Anisotropia , Feminino , Humanos , Masculino , Inquéritos e Questionários
11.
J Chem Phys ; 150(2): 024906, 2019 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-30646714

RESUMO

Effects of multi-gradient fields on the transport of a polymer chain are investigated using Langevin dynamics simulations. We observe that the natural frequency of tumbling follows Wi 0.66 scaling, where Wi is the Weissenberg number. The distribution of angular tumbling time has exponentially decaying tails, and at high Wi, it deviates from Poisson behavior. Competition between the velocity gradient, which results in a shear flow in the system, and the solvent quality gradient arising due to the interaction among monomers reveals that there is another scaling associated with the angular tumbling time distribution. Moreover, at low temperature, we observe unusual behavior that at intermediate shear rates, the decay rate ν decreases with Wi.

12.
J Neurosci Res ; 96(6): 1104-1118, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29315714

RESUMO

BACKGROUND: Single ventricle heart disease (SVHD) adolescents show cognitive impairments and anxiety and depressive symptoms, indicating the possibility of brain injury in regions that control these functions. However, brain tissue integrity in cognition, anxiety, and depression regulatory sites in SVHD remains unclear. We examined brain tissue changes in SVHD compared to controls using T2-relaxometry procedures, which measure free water content and show tissue injury. METHODS: Proton-density and T2-weighted images, using a 3.0-Tesla MRI, as well as anxiety (Beck anxiety inventory [BAI]), depressive symptoms (patient health questionnaire-9 [PHQ-9]), and cognition (wide range assessment of memory and learning 2 [WRAML2] and Montreal cognitive assessment [MoCA]) data were collected from 20 SVHD (age: 15.8 ± 1.1 years, male/female: 11/9) and 36 controls (age: 16.0 ± 1.1 years, male/female: 19/17). Whole-brain T2-relaxation maps were calculated, normalized to a common space, smoothed, and compared between groups and sexes (analysis of covariance; covariates: age, sex; p < 0.001). RESULTS: SVHD subjects showed significantly increased BAI and PHQ-9 and reduced MoCA and WRAML2 scores over controls. Several brain regions in SVHD showed increased T2-relaxation values (chronic injury), including the cingulate, and insula, hippocampus/para-hippocampal gyrus, thalamus, hypothalamus, amygdala, frontal white matter, corpus callosum, brainstem, and cerebellar areas. Decreased T2-relaxation values (acute injury) emerged in a few regions, including the prefrontal and cerebellar cortices in SVHD over controls. In addition, male SVHD showed more brain changes over female SVHD. CONCLUSIONS: Adolescents with SVHD showed significant brain injury with variable male-female differences in areas that control cognition, anxiety, and depression, which may contribute to functional deficits found in the condition.


Assuntos
Ansiedade/etiologia , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/etiologia , Disfunção Cognitiva/etiologia , Depressão/etiologia , Cardiopatias/patologia , Cardiopatias/psicologia , Adolescente , Ansiedade/diagnóstico por imagem , Disfunção Cognitiva/diagnóstico por imagem , Estudos Transversais , Depressão/diagnóstico por imagem , Feminino , Humanos , Masculino , Fatores Sexuais
14.
Neuroradiology ; 60(2): 199-205, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29230507

RESUMO

PURPOSE: Schizophrenia patients show cognitive and mood impairments, including memory loss and depression, suggesting damage in the brain regions. The hippocampus is a brain structure that is significantly involved in memory and mood function and shows impairment in schizophrenia. In the present study, we examined the regional hippocampal changes in schizophrenia patients using voxel-based morphometry (VBM), Freesurfer, and proton magnetic resonance spectroscopy (1H MRS) procedures. METHODS: 1H MRS and high-resolution T1-weighted magnetic resonance imaging were collected in both healthy control subjects (N = 28) and schizophrenia patients (N = 28) using 3-Tesla whole body MRI system. Regional hippocampal volume was analyzed using VBM and Freesufer procedures. The relative ratios of the neurometabolites were calculated using linear combination model (LCModel). RESULTS: Compared to controls, schizophrenia patients showed significantly decreased gray matter volume in the hippocampus. Schizophrenia patients also showed significantly reduced glutamate (Glu) and myo-inositol (mI) ratios in the hippocampus. Additionally, significant positive correlation between gray matter volume and Glu/tCr was also observed in the hippocampus in schizophrenia. CONCLUSION: Our findings provide an evidence for a possible association between structural deficits and metabolic alterations in schizophrenia patients.


Assuntos
Substância Cinzenta/patologia , Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética , Espectroscopia de Prótons por Ressonância Magnética , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/patologia , Adulto , Estudos de Casos e Controles , Feminino , Ácido Glutâmico/metabolismo , Hipocampo/metabolismo , Humanos , Inositol/metabolismo , Masculino , Esquizofrenia/metabolismo , Software
16.
Mol Biol Rep ; 41(9): 5989-96, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24973880

RESUMO

Ran is a multifunctional small GTPase involved in important cellular activities like nucleocytoplasmic transport, mitotic spindle assembly, nuclear envelope formation, etc., but is also known to be differentially expressed in response to abiotic stress, particularly low temperature. We have over-expressed Lepidium latifolium (Fam. Brassicaceae) Ran gene in tobacco to study the response of the plants to cold stress (24 h; 4 °C). Transformation of the tobacco plants was verified using PCR targeting Ran gene and co-transformed selectable marker gene nptII. Segregation in Mendelian ratios was validated in five transgenic lines by germination of T1 and T2 seeds on moist filter papers containing 150 mg/l kanamycin. Higher levels of electrolyte leakage and lipid peroxidation pointed towards hypersensitivity of plants. Similarly, lesser proline accumulation compared to wild types also indicated susceptibility of plants to death under chilling conditions. Specific activity of antioxidant enzymes superoxide dismutase and glutathione reductase was also measured under stressed and control conditions. A variation was observed across the different lines, and four out of five lines showed lesser specific activity compared to wild type plants, thus indicating reduced capability of scavenging free radicals. In totality, a strong evidence on induced hypersensitivity to cold stress has been collected which may further be helpful in designing appropriate strategies for engineering crop plants for survival under cold stress conditions.


Assuntos
Resposta ao Choque Frio/genética , Lepidium/genética , Nicotiana/genética , Proteínas de Plantas/genética , Plantas Geneticamente Modificadas/genética , Proteína ran de Ligação ao GTP/genética , Genes de Plantas , Glutationa Redutase/metabolismo , Peroxidação de Lipídeos/genética , Plantas Geneticamente Modificadas/metabolismo , Superóxido Dismutase/metabolismo , Transgenes , Regulação para Cima
17.
Mol Biol Rep ; 41(11): 7479-89, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25106524

RESUMO

We report elevated biomass and altered growth characteristics of tobacco plants up on transformation with a NAC (NAM, ATAF1/2,CUC2) gene (GenBank Accession FJ754254) isolated from Lepidium latifolium L. (LlaNAC). Transgenic plants showed significant differences in fresh weight, midrib length of longest leaf, leaf area, height of the plant, root and shoot weights, etc. during vegetative phase. On 100th day after sowing (DAS), plants of transgenic lines were 2-3 times taller than the wild type plants, though no significant difference was recorded in moisture contents of any of the plant tissues. Over-expression of NAC gene up to 2,000 fold was recorded in leaves of transgenic plants on 100th DAS. Interestingly, transgenic plants showed significantly shortened (P(t) = 0.02-0.04) life cycle, as they showed a completely altered growth behaviour. Transgenic plants entered reproductive phase earlier by 60 days, with lines NC2 and NC7b entering first, followed by line NC10. However, the time period spent in the reproductive phase by the plant was nearly twice in case of transgenic lines NC2, NC7b and NC10, as compared to the wild type plants. Despite that, these lines completed their life cycle in 45-60 days lesser than the time taken by wild-type tobacco plants. No difference was recorded in fruit and seed yield of transgenic or wild type plants. To the best of our knowledge, this is the first report on over-expression of NAC gene causing altered growth and biomass patterns. We expect this study to become an important reference towards future engineering of plants for fuel and fodder purposes.


Assuntos
Biocombustíveis , Regulação da Expressão Gênica de Plantas/fisiologia , Engenharia Genética/métodos , Lepidium/genética , Nicotiana/crescimento & desenvolvimento , Proteínas de Plantas/genética , Transformação Genética/genética , Aclimatação/genética , Biomassa , Temperatura Baixa , Regulação da Expressão Gênica de Plantas/genética , Lepidium/metabolismo , Estágios do Ciclo de Vida/genética , Nicotiana/genética
18.
Neuroradiology ; 56(5): 413-22, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24562867

RESUMO

INTRODUCTION: To investigate whether the motor functional alterations in schizophrenia (SZ) are also associated with structural changes in the related brain areas using functional magnetic resonance imaging (fMRI) and voxel-based morphometry (VBM). METHODS: A sample of 14 right-handed SZ patients and 14 right-handed healthy control subjects matched for age, sex, and education were examined with structural high-resolution T1-weighted MRI; fMRI images were obtained during right index finger-tapping task in the same session. RESULTS: fMRI results showed reduced functional activation in the motor areas (contralateral precentral and postcentral gyrus) and ipsilateral cerebellum in SZ subjects as compared to healthy controls (n = 14). VBM analysis also revealed reduced grey matter in motor areas and white matter reduction in cerebellum of SZ subjects as compared to controls. CONCLUSION: The present study provides an evidence for a possible association between structural alterations in the motor cortex and disturbed functional activation in the motor areas in persons affected with SZ during a simple finger-tapping task.


Assuntos
Imageamento por Ressonância Magnética , Córtex Motor/fisiopatologia , Esquizofrenia/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Neuroradiology ; 56(1): 69-77, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24221533

RESUMO

INTRODUCTION: Chronic alcohol abuse has been traditionally associated with impaired cognitive abilities. The deficits are most evident in higher order cognitive functions, such as abstract reasoning, problem solving and visuospatial processing. The present study sought to increase current understanding of the neuropsychological basis of poor abstract reasoning abilities in alcohol-dependent subjects using functional magnetic resonance imaging (fMRI). METHODS: An abstract reasoning task-based fMRI study was carried out on alcohol-dependent subjects (n = 18) and healthy controls (n = 18) to examine neural activation pattern. The study was carried out using a 3-T whole-body magnetic resonance scanner. Preprocessing and post processing was performed using SPM 8 software. RESULTS: Behavioral data indicated that alcohol-dependent subjects took more time than controls for performing the task but there was no significant difference in their response accuracy. Analysis of the fMRI data indicated that for solving abstract reasoning-based problems, alcohol-dependent subjects showed enhanced right frontoparietal neural activation involving inferior frontal gyrus, post central gyrus, superior parietal lobule, and occipito-temporal gyrus. CONCLUSIONS: The extensive activation observed in alcohol dependents as compared to controls suggests that alcohol dependents recruit additional brain areas to meet the behavioral demands for equivalent task performance. The results are consistent with previous fMRI studies suggesting decreased neural efficiency of relevant brain networks or compensatory mechanisms for the execution of task for showing an equivalent performance.


Assuntos
Alcoolismo/complicações , Alcoolismo/fisiopatologia , Mapeamento Encefálico/métodos , Córtex Cerebral/fisiopatologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Função Executiva , Adulto , Alcoolismo/diagnóstico , Transtornos Cognitivos/diagnóstico , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Resolução de Problemas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Análise e Desempenho de Tarefas
20.
Physiol Mol Biol Plants ; 20(1): 139-42, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24554848

RESUMO

Oil-rich seeds of Jatropha curcas are being focussed as a source of bio-diesel. However, prior to its industrial use, a lot of crop improvement efforts are required in Jatropha. Availability of a large number of EST sequences of Jatropha in public domain allow identification of candidate genes for several agronomic characters including oil content in seeds. Here, we have analysed 42,477 ESTs of Jatropha spanning 22.9 Mbp for microsatellites and fatty acid metabolism related sequences. Unigene sequences were built using CAP 3 programme resulted in 12,358 contigs and 5,730 singlets. Nearly, 8 % unigenes showed presence of microsatellites, slightly over-represented compared to their occurrence in ESTs. Most of the microsatellites were either di- or tri-nucleotide repeats, while other categories of tetra-, penta- and hexa-nucleotide repeats together constituted ~4 % of total microsatellites. Assessment of functional relevance of unigenes was carried out using Blast2GO using its default settings. The overall sequence similarity level against sequences in 'nr' database was >80 %. A total of 931 sequences that participated in any of the pathways related to fatty acid or lipid metabolism were found at GO level 6. Among these, GO terms "Fatty acid metabolic process" and "Fatty acid biosynthetic process" were most over-represented. Overall, our work has due relevance in identifying molecular markers for the candidate genes for oil content in Jatropha seeds, and will prove to be an important reference for further studies for identification of trait specific markers in Jatropha.

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