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1.
Materials (Basel) ; 16(24)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38138741

RESUMO

We propose a method of manipulating the coercivity of anisotropic hydrogenation-disproportionation-desorption-recombination (HDDR) powders to fabricate high-remanence and fine-grained Nd-Fe-B magnets using only hot-pressing without a subsequent hot-deformation process. By reducing the Nd content of anisotropic HDDR precursors such that their coercivity (Hcj) is lowered, the c-axis of each HDDR particle is well-aligned parallel to the direction of the applied magnetic field during the magnetic alignment step. This is because the magnetic repulsive force between adjacent particles, determined by their remanent magnetization, decreases as a result of the low coercivity of each particle. Therefore, after hot-pressing the low-Hcj HDDR powders, a significantly higher remanence (11.2 kG) is achieved in the bulk than that achieved by hot-pressing the high-Hcj HDDR powders (8.2 kG). It is clearly confirmed by the large-scale electron backscatter diffraction (EBSD) analysis that the alignment of the c-axis of each anisotropic HDDR particle in the bulk is improved when low-Hcj HDDR powders are used to fabricate hot-pressed magnets. This coercivity manipulation of HDDR powders can be a helpful method to expand the use of HDDR powders in fabricating anisotropic Nd-Fe-B bulk magnets.

2.
J Am Chem Soc ; 145(44): 23925-23938, 2023 11 08.
Artigo em Inglês | MEDLINE | ID: mdl-37883679

RESUMO

Protein glycosylation is a common post-translational modification on extracellular proteins. The conformational dynamics of several glycoproteins have been characterized by hydrogen/deuterium exchange mass spectrometry (HDX-MS). However, it is, in most cases, not possible to extract information about glycan conformation and dynamics due to the general difficulty of separating the deuterium content of the glycan from that of the peptide (in particular, for O-linked glycans). Here, we investigate whether the fragmentation of protonated glycopeptides by collision-induced dissociation (CID) can be used to determine the solution-specific deuterium content of the glycan. Central to this concept is that glycopeptides can undergo a facile loss of glycans upon CID, thereby allowing for the determination of their masses. However, an essential prerequisite is that hydrogen and deuterium (H/D) scrambling can be kept in check. Therefore, we have measured the degree of scrambling upon glycosidic bond cleavage in glycopeptides that differ in the conformational flexibility of their backbone and glycosylation pattern. Our results show that complete scrambling precedes the glycosidic bond cleavage in normal glycopeptides derived from a glycoprotein; i.e., all labile hydrogens have undergone positional randomization prior to loss of the glycan. In contrast, the glycosidic bond cleavage occurs without any scrambling in the glycopeptide antibiotic vancomycin, reflecting that the glycan cannot interact with the peptide moiety due to a conformationally restricted backbone as revealed by molecular dynamics simulations. Scrambling is also inhibited, albeit to a lesser degree, in the conformationally restricted glycopeptides ristocetin and its pseudoaglycone, demonstrating that scrambling depends on an intricate interplay between the flexibility and proximity of the glycan and the peptide backbone.


Assuntos
Glicopeptídeos , Hidrogênio , Glicopeptídeos/química , Deutério , Peptídeos/química , Glicoproteínas/química , Polissacarídeos/química
4.
Chem Commun (Camb) ; 58(81): 11442-11445, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36148584

RESUMO

A simple, scalable spray drying method was developed for high-yield epsilon iron oxide (ε-Fe2O3) synthesis. The ε-Fe2O3 particle size can be tailored by varying the annealing temperature and molar ratio of Fe/Si, producing a high-purity ε-phase. This strategy also enables ferromagnetic resonance tuning, making it potentially usable in millimeter-wave absorbers.

5.
Dalton Trans ; 50(41): 14560-14565, 2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34643202

RESUMO

We studied the structural and magnetic properties of BaFe12O19 (BaM) nanoparticles synthesized by a co-precipitation route based on a modified citrate process. The lattice contraction of co-precipitated BaM nanoparticles is detected after prolonged sintering at 900 °C. In addition, investigation with X-ray photoelectron spectroscopy (XPS) provides evidence of a highly enhanced population of oxygen vacancies. The lattice distortion and formation of oxygen vacancies are attributed to a direct result of substitutional incorporation of smaller Na ions into Ba2+ sites in the lattice of BaM during prolonged annealing. The aliovalent impurities are assumed to be originated from NaOH which has been incorporated as a pH modifier. Magnon scattering is detected at 1640 cm-1 in the low temperature Raman spectra of BaM. Minimization of the magnon peak is also identified after prolonged annealing, which indicates oxygen vacancy-induced collapse of strong anti-ferromagnetic interaction between Fe3+ ions in the bipyramidal sites and the octahedral sites in BaM nanoparticles. As a result, the saturation magnetization (Ms) of BaM nanoparticles is enhanced by the onset of local ferromagnetic interaction induced by the collapse of antiferromagnetic interaction between oppositely aligned spins. In this study, we re-investigated the evolution of structural and magnetic properties with prolonged annealing of BaM nanoparticles and the effects of residual Na ions are also discussed.

6.
Mol Psychiatry ; 26(7): 3395-3406, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33658605

RESUMO

We identified biologically relevant moderators of response to tumor necrosis factor (TNF)-α inhibitor, infliximab, among 60 individuals with bipolar depression. Data were derived from a 12-week, randomized, placebo-controlled clinical trial secondarily evaluating the efficacy of infliximab on a measure of anhedonia (i.e., Snaith-Hamilton Pleasure Scale). Three inflammatory biotypes were derived from peripheral cytokine measurements using an iterative, machine learning-based approach. Infliximab-randomized participants classified as biotype 3 exhibited lower baseline concentrations of pro- and anti-inflammatory cytokines and soluble TNF receptor-1 and reported greater pro-hedonic improvements, relative to those classified as biotype 1 or 2. Pretreatment biotypes also moderated changes in neuroinflammatory substrates relevant to infliximab's hypothesized mechanism of action. Neuronal origin-enriched extracellular vesicle (NEV) protein concentrations were reduced to two factors using principal axis factoring: phosphorylated nuclear factorκB (p-NFκB), Fas-associated death domain (p-FADD), and IκB kinase (p-IKKα/ß) and TNF receptor-1 (TNFR1) comprised factor "NEV1," whereas phosphorylated insulin receptor substrate-1 (p-IRS1), p38 mitogen-activated protein kinase (p-p38), and c-Jun N-terminal kinase (p-JNK) constituted "NEV2". Among infliximab-randomized subjects classified as biotype 3, NEV1 scores were decreased at weeks 2 and 6 and increased at week 12, relative to baseline, and NEV2 scores increased over time. Decreases in NEV1 scores and increases in NEV2 scores were associated with greater reductions in anhedonic symptoms in our classification and regression tree model (r2 = 0.22, RMSE = 0.08). Our findings provide preliminary evidence supporting the hypothesis that the pro-hedonic effects of infliximab require modulation of multiple TNF-α signaling pathways, including NF-κB, IRS1, and MAPK.


Assuntos
Transtorno Bipolar , Infliximab/uso terapêutico , Biomarcadores , Transtorno Bipolar/tratamento farmacológico , Humanos , Proteínas Substratos do Receptor de Insulina , Sistema de Sinalização das MAP Quinases , NF-kappa B , Fator de Necrose Tumoral alfa
7.
Materials (Basel) ; 14(1)2021 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-33401618

RESUMO

Hexagonal boron nitride was synthesized by pyrolysis using boric acid and melamine. At this time, to impart luminescence, rare earth cerium ions were added to synthesize hexagonal boron nitride nanophosphor particles exhibiting deep blue emission. To investigate the changes in crystallinity and luminescence according to the re-heating temperature, samples which had been subjected to pyrolysis at 900 °C were subjected to re-heating from 1100 °C to 1400 °C. Crystallinity and luminescence were enhanced according to changes in the reheating temperature. The synthesized cerium ion-doped hexagonal boron nitride nanoparticle phosphor was applied to the anti-counterfeiting field to prepare an ink that can only be identified under UV light.

8.
Bull World Health Organ ; 98(10): 683-697H, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-33177758

RESUMO

OBJECTIVE: To evaluate the development and implementation of clinical practice guidelines for the management of depression globally. METHODS: We conducted a systematic review of existing guidelines for the management of depression in adults with major depressive or bipolar disorder. For each identified guideline, we assessed compliance with measures of guideline development quality (such as transparency in guideline development processes and funding, multidisciplinary author group composition, systematic review of comparative efficacy research) and implementation (such as quality indicators). We compared guidelines from low- and middle-income countries with those from high-income countries. FINDINGS: We identified 82 national and 13 international clinical practice guidelines from 83 countries in 27 languages. Guideline development processes and funding sources were explicitly specified in a smaller proportion of guidelines from low- and middle-income countries (8/29; 28%) relative to high-income countries (35/58; 60%). Fewer guidelines (2/29; 7%) from low- and middle-income countries, relative to high-income countries (22/58; 38%), were authored by a multidisciplinary development group. A systematic review of comparative effectiveness was conducted in 31% (9/29) of low- and middle-income country guidelines versus 71% (41/58) of high-income country guidelines. Only 10% (3/29) of low- and middle-income country and 19% (11/58) of high-income country guidelines described plans to assess quality indicators or recommendation adherence. CONCLUSION: Globally, guideline implementation is inadequately planned, reported and measured. Narrowing disparities in the development and implementation of guidelines in low- and middle-income countries is a priority. Future guidelines should present strategies to implement recommendations and measure feasibility, cost-effectiveness and impact on health outcomes.


Assuntos
Depressão , Transtorno Depressivo Maior , Adulto , Depressão/terapia , Humanos
10.
Brain Sci ; 10(5)2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32429065

RESUMO

Milnacipran is a reuptake inhibitor of both serotonin and noradrenaline, used in the treatment of fibromyalgia with severe depression. However, few studies have been conducted on the efficacies of milnacipran drug on the functional connectivity of the neural network. The authors aimed to find the correlation between the drug efficacy and the changes in neural network in fibromyalgia patients. Resting-state-functional magnetic resonance imaging (rs-fMRI) were obtained before and after milnacipran drug administration. Graph theory indexes and small-worldness were calculated using preprocessed blood-oxygen-level-dependent signals from the rs-fMRI scans of 14 brain regions-of-interest. Statistical analyses were conducted to compare the topological network parameters. Significant changes in the neural network indexes appeared in three of the 14 brain regions-of-interest. In the pain network, the average path length on the left side of Brodmann area 32 was shortened. In the default mode network, functional connectivity changes were observed in the left lateral parietal cortex and medial prefrontal cortex. In the left lateral parietal cortex, the degree and betweenness centrality increased, whereas the clustering coefficient decreased. In the medial prefrontal cortex, local efficiency decreased. The small-worldness declined after milnacipran medication. The present results demonstrate that functional connectivity indexes in the brains of female fibromyalgia patients obtained from rs-fMRI data can be used as potential prognosis markers of milnacipran drug treatment.

11.
Ann Clin Psychiatry ; 31(1): 17-26, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30372511

RESUMO

BACKGROUND: The aim of this study was to examine the role of perceived sleep quality in predicting subjective as well as objective cognitive function in adults with major depressive disorder (MDD). METHODS: Adults with recurrent MDD (n = 100) experiencing a major depressive episode of at least moderate severity and age-, sex-, and education-matched healthy controls (HC) (n = 100) were recruited to participate in a clinical trial validating the THINC-integrated tool (THINC-it; NCT02508493) for cognitive function. The THINC-it includes subjective and objective measures of cognitive function. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). RESULTS: Compared with HC, individuals with MDD reported significantly poorer sleep quality, as assessed by domain and global PSQI scores (all P values <.05). Both perceived sleep quality (P < .001) and depression severity (P = .002) were found to independently predict impairments in subjective cognitive performance. Only perceived sleep quality predicted objective cognitive impairments (P = .017). Exploratory mediation analysis revealed depression severity to be a partial mediator of the relationship between perceived sleep quality and subjective cognitive performance (95% confidence interval [CI]: -0.56, -0.33). CONCLUSIONS: The results indicate that the subjective and objective cognitive impairments are differentially related to perceived sleep quality and depression severity and emphasize the importance of treating sleep disturbances in MDD.


Assuntos
Cognição/fisiologia , Transtorno Depressivo Maior/psicologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adulto , Feminino , Humanos , Masculino , Testes Neuropsicológicos/estatística & dados numéricos , Recidiva , Inquéritos e Questionários
12.
Harv Rev Psychiatry ; 26(5): 241-249, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30188336

RESUMO

LEARNING OBJECTIVES: After participating in this activity, learners should be better able to:• Characterize cognitive dysfunction in patients with major depressive disorder.• Evaluate approaches to treating cognitive dysfunction in patients with major depressive disorder. ABSTRACT: Cognitive dysfunction is a core psychopathological domain in major depressive disorder (MDD) and is no longer considered to be a pseudo-specific phenomenon. Cognitive dysfunction in MDD is a principal determinant of patient-reported outcomes, which, hitherto, have been insufficiently targeted with existing multimodal treatments for MDD. The neural structures and substructures subserving cognitive function in MDD overlap with, yet are discrete from, those subserving emotion processing and affect regulation. Several modifiable factors influence the presence and extent of cognitive dysfunction in MDD, including clinical features (e.g., episode frequency and illness duration), comorbidity (e.g., obesity and diabetes), and iatrogenic artefact. Screening and measurement tools that comport with the clinical ecosystem are available to detect and measure cognitive function in MDD. Notwithstanding the availability of select antidepressants capable of exerting procognitive effects, most have not been sufficiently studied or rigorously evaluated. Promising pharmacological avenues, as well as psychosocial, behavioral, chronotherapeutic, and complementary alternative approaches, are currently being investigated.


Assuntos
Disfunção Cognitiva , Transtorno Depressivo Maior , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/fisiopatologia , Disfunção Cognitiva/terapia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/fisiopatologia , Transtorno Depressivo Maior/terapia , Humanos
13.
J Affect Disord ; 238: 228-232, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29886204

RESUMO

BACKGROUND AND OBJECTIVES: This study evaluated the association between self-reported anxiety and objective/subjective measures of cognitive performance in adults with Major Depressive Disorder (MDD). METHODS: Acutely depressed subjects with recurrent MDD (n = 100) and age-, sex-, and education-matched healthy controls (HC; n = 100) between the ages of 18 and 65 completed the cross-sectional validation study of the THINC-integrated tool (THINC-it; ClinicalTrials.gov: NCT02508493). Objective cognitive performance was assessed using the THINC-it, and subjective cognitive impairment with the Perceived Deficits Questionnaire for Depression-5-item. Subjects also completed the Generalized Anxiety Disorder-7-item (GAD-7) questionnaire. RESULTS: Subjects with MDD reported significantly more anxiety symptoms, as assessed by the GAD-7, compared to HC (p < 0.001). Linear regression analysis determined that anxiety symptoms significantly accounted for 70.4% of the variability in subjective cognitive impairment, adjusting for depression severity. Moreover, subjects' ratings of the difficulties caused by their anxiety were reported as significantly more severe among subjects with MDD when compared to HC (p < 0.001). Likewise, greater self-reported difficulties with anxiety significantly predicted 57.8% of the variability in subjective cognitive impairment, adjusting for depression severity. Neither anxiety symptoms nor impairment due to anxiety symptoms predicted objective cognitive performance. LIMITATIONS: Subjects were not prospectively verified to have a clinical diagnosis of GAD. Rather, this study examined the relationships between symptoms of generalized anxiety, assessed using a brief screening tool, and subjective and objective cognitive function. CONCLUSIONS: Results from the current study indicate that adults with MDD and high levels of self-reported anxiety are significantly more likely to report experiencing subjective cognitive dysfunction.


Assuntos
Cognição , Disfunção Cognitiva/psicologia , Transtorno Depressivo Maior/psicologia , Autorrelato , Adulto , Idoso , Ansiedade/psicologia , Estudos Transversais , Feminino , Humanos , Masculino , Programas de Rastreamento , Pessoa de Meia-Idade , Recidiva , Análise de Regressão , Inquéritos e Questionários , Adulto Jovem
14.
Ann Clin Psychiatry ; 30(1): 25-31, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29373615

RESUMO

BACKGROUND: Individuals with binge eating disorder (BED) are differentially affected by attention-deficit/hyperactivity disorder (ADHD), obesity, and substance use disorder. We have investigated to what extent cognitive deficits are relevant to binge eating behavior (BEB). METHODS: Data from the International Mood Disorders Collaborative Project were retrospectively and cross-sectionally analyzed to compare individuals with and without BEB on measures of anhedonia and general cognitive functions (n = 566). BEB was assessed using items from the Mini International Neuropsychiatric Interview Plus 5.0.0 for DSM-IV-TR that correspond with DSM-5-defined diagnostic criteria for BED. Individuals currently prescribed benzodiazepines were excluded from analyses. RESULTS: Individuals with BEB were more likely to exhibit anhedonia (P = .044) and general cognitive (P = .005) symptoms, when compared to those without BEB. We also observed that individuals with BEB were more likely to have specific psychiatric (eg, ADHD) and medical (eg, obesity) disorders (P < .05). CONCLUSIONS: Our results suggest that a central disturbance in cognitive processes may be mechanistically relevant to the cause and treatment of BEB in adults.


Assuntos
Transtorno da Compulsão Alimentar/psicologia , Transtornos Cognitivos/psicologia , Escalas de Graduação Psiquiátrica/estatística & dados numéricos , Adulto , Anedonia/fisiologia , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade , Estudos Retrospectivos
15.
J Affect Disord ; 227: 406-415, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29154157

RESUMO

INTRODUCTION: Work-related disability and productivity loss in Major Depressive Disorder (MDD) are critical determinants of patient quality of life and contribute significantly to the human and economic costs of MDD. Notwithstanding the return to work and pre-morbid levels of functioning as a critical therapeutic objective among individuals with MDD, it is unclear whether antidepressant treatment significantly and reliably improves measures of workplace functioning. Herein, we investigate to what extent antidepressant treatment improves workplace functioning among adults with MDD. METHODS: We conducted a systematic review of randomized, double-blind, placebo-controlled or active comparator clinical trials primarily or secondarily investigating the efficacy of antidepressant agents on subjective ratings of workplace functioning and/or measures of work absence. RESULTS: Thirteen placebo-controlled and four active comparator clinical trials reported on the efficacy of agomelatine, bupropion, desvenlafaxine, duloxetine, fluoxetine, levomilnacipran, paroxetine, sertraline, venlafaxine, or vortioxetine on subjective measures of workplace impairment. Overall, antidepressant treatment improved standardized measures of workplace functioning (e.g., Sheehan Disability Scale-work item). One placebo-controlled trial of agomelatine and one clinical trial comparing the efficacy of vortioxetine to that of venlafaxine had mixed results on measures of work absence. LIMITATIONS: Included interventional trials evaluated work-related disability as a secondary outcome using subjective rating scales. CONCLUSION: Extant data suggest that antidepressant treatment improves workplace outcomes in MDD. The capability of antidepressants in improving measures of workplace functioning should be considered in cost-benefit analyses to better inform cost-modelling studies pertaining to antidepressant therapy.


Assuntos
Antidepressivos/uso terapêutico , Transtorno Depressivo Maior/tratamento farmacológico , Desempenho Profissional , Antidepressivos/efeitos adversos , Efeitos Psicossociais da Doença , Análise Custo-Benefício , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/economia , Transtorno Depressivo Maior/psicologia , Avaliação da Deficiência , Método Duplo-Cego , Humanos , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Local de Trabalho
16.
Scand J Pain ; 15: 62-67, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28850348

RESUMO

OBJECTIVES: To examine the role of pain on cognitive function in adults with major depressive disorder (MDD). METHODS: Adults (18-65) with a Diagnostic and Statistical Manual - Fifth Edition (DSM-5)-defined diagnosis of MDD experiencing a current major depressive episode (MDE) were enrolled (nMDD=100). All subjects with MDD were matched in age, sex, and years of education to healthy controls (HC) (nHC=100) for comparison. Cognitive function was assessed using the recently validated THINC-integrated tool (THINC-it), which comprises variants of the choice reaction time (i.e., THINC-it: Spotter), One-Back (i.e., THINC-it: Symbol Check), Digit Symbol Substitution Test (i.e., THINC-it: Codebreaker), Trail Making Test - Part B (i.e., THINC-it: Trails), as well as the Perceived Deficits Questionnaire for Depression - 5-item (i.e., THINC-it: PDQ-5-D). A global index of objective cognitive function was computed using objective measures from the THINC-it, while self-rated cognitive deficits were measured using the PDQ-5-D. Pain was measured using a Visual Analogue Scale (VAS). Regression analyses evaluated the role of pain in predicting objective and subjective cognitive function. RESULTS: A significant between-group differences on the VAS was observed (p<0.001), with individuals with MDD reporting higher pain severity as evidenced by higher scores on the VAS than HC. Significant interaction effects were observed between self -rated cognitive deficits and pain ratings (p<0.001) on objective cognitive performance (after adjusting for MADRS total score), suggesting that pain moderates the association between self-rated and objective cognitive function. CONCLUSIONS: Results indicated that pain is associated with increased self-rated and objective cognitive deficits in adults with MDD. IMPLICATIONS: The study herein provides preliminary evidence demonstrating that adults with MDD reporting pain symptomatology and poorer subjective cognitive function is predictive of poorer objective cognitive performance. THINC-it is capable of detecting cognitive dysfunction amongst adults with MDD and pain.


Assuntos
Disfunção Cognitiva/etiologia , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/psicologia , Dor/complicações , Dor/psicologia , Adolescente , Adulto , Idoso , Cognição , Disfunção Cognitiva/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Estudos Prospectivos , Adulto Jovem
17.
J Affect Disord ; 222: 14-20, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28667888

RESUMO

BACKGROUND: Psychosocial impairment represents an important treatment target in major depressive disorder (MDD). The majority of patients with MDD do not regain premorbid levels of psychosocial functioning despite the resolution of core depressive symptoms. This study aimed to investigate the respective effects of cognitive function and depression severity on impaired psychosocial function in MDD. METHODS: Adults aged 18-65 with moderate-to-severe MDD (n = 100) and age-, sex-, and education-matched healthy controls participated in a cross-sectional study validating the THINC-integrated tool (THINC-it), a cognitive screening tool comprised of objective and subjective measures of cognitive function. Depression severity was assessed using the Montgomery-Åsberg Depression Rating Scale and psychosocial function was assessed using the Sheehan Disability Scale (SDS). RESULTS: Subjects with MDD reported greater impairment in psychosocial function than healthy controls, with significant differences in SDS total and domain scores (ps < .01) after controlling for age, sex, and education. Generalized linear models indicated that subjective cognitive function was most strongly associated with SDS total score (RR = .14, p = .01) and SDS domains of work/school (RR = .15, p = .03), family and home responsibilities (RR = .15, p = .02), and economic days lost (RR = .18, p =.03). Depression severity was most strongly associated with SDS social life (RR = .08, p < .01) and economic days underproductive (RR = .07, p < .01). Objective cognitive function was not significantly associated with any SDS outcomes. LIMITATIONS: The cross-sectional, observational study design limits temporal inferences. The self-report nature of measures included may have influenced associations observed. Potential medication effects are not noted. CONCLUSIONS: Cognitive deficits, as measured by the THINC-it, are associated with significant psychosocial impairment in MDD. These results provide empirical support for the assessment of both subjective and objective measures of cognition, as they are not associated with each other and have differential effects on functional trajectory.


Assuntos
Disfunção Cognitiva/diagnóstico , Transtorno Depressivo Maior/diagnóstico , Adolescente , Adulto , Idoso , Transtornos Cognitivos/diagnóstico , Disfunção Cognitiva/psicologia , Estudos Transversais , Depressão/diagnóstico , Transtorno Depressivo Maior/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Autorrelato , Comportamento Social
18.
Sci Rep ; 6: 28696, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27345599

RESUMO

A six-lobed membrane spanning cellulose synthesis complex (CSC) containing multiple cellulose synthase (CESA) glycosyltransferases mediates cellulose microfibril formation. The number of CESAs in the CSC has been debated for decades in light of changing estimates of the diameter of the smallest microfibril formed from the ß-1,4 glucan chains synthesized by one CSC. We obtained more direct evidence through generating improved transmission electron microscopy (TEM) images and image averages of the rosette-type CSC, revealing the frequent triangularity and average cross-sectional area in the plasma membrane of its individual lobes. Trimeric oligomers of two alternative CESA computational models corresponded well with individual lobe geometry. A six-fold assembly of the trimeric computational oligomer had the lowest potential energy per monomer and was consistent with rosette CSC morphology. Negative stain TEM and image averaging showed the triangularity of a recombinant CESA cytosolic domain, consistent with previous modeling of its trimeric nature from small angle scattering (SAXS) data. Six trimeric SAXS models nearly filled the space below an average FF-TEM image of the rosette CSC. In summary, the multifaceted data support a rosette CSC with 18 CESAs that mediates the synthesis of a fundamental microfibril composed of 18 glucan chains.


Assuntos
Celulose/química , Glucosiltransferases/química , Modelos Moleculares , Proteínas de Plantas/química , Dobramento de Proteína , Celulose/biossíntese , Domínios Proteicos , Estrutura Quaternária de Proteína
19.
Plant Cell ; 28(1): 202-18, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26672067

RESUMO

Plant growth and survival depend upon the activity of membrane transporters that control the movement and distribution of solutes into, around, and out of plants. Although many plant transporters are known, their intrinsic properties make them difficult to study. In barley (Hordeum vulgare), the root anion-permeable transporter Bot1 plays a key role in tolerance to high soil boron, facilitating the efflux of borate from cells. However, its three-dimensional structure is unavailable and the molecular basis of its permeation function is unknown. Using an integrative platform of computational, biophysical, and biochemical tools as well as molecular biology, electrophysiology, and bioinformatics, we provide insight into the origin of transport function of Bot1. An atomistic model, supported by atomic force microscopy measurements, reveals that the protein folds into 13 transmembrane-spanning and five cytoplasmic α-helices. We predict a trimeric assembly of Bot1 and the presence of a Na(+) ion binding site, located in the proximity of a pore that conducts anions. Patch-clamp electrophysiology of Bot1 detects Na(+)-dependent polyvalent anion transport in a Nernstian manner with channel-like characteristics. Using alanine scanning, molecular dynamics simulations, and transport measurements, we show that conductance by Bot1 is abolished by removal of the Na(+) ion binding site. Our data enhance the understanding of the permeation functions of Bot1.


Assuntos
Hordeum/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Plantas/metabolismo , Sódio/metabolismo , Ânions/metabolismo , Sítios de Ligação , Boratos/metabolismo , Sistema Livre de Células , Simulação por Computador , Bicamadas Lipídicas/metabolismo , Lipossomos/metabolismo , Proteínas de Membrana Transportadoras/química , Modelos Moleculares , Permeabilidade , Pichia/metabolismo , Proteínas de Plantas/química , Dobramento de Proteína , Multimerização Proteica , Triticum/metabolismo
20.
J Nanosci Nanotechnol ; 15(2): 1221-8, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26353637

RESUMO

We demonstrate that chitosan prepatterns can generate not only highly periodic DNA pattern but also various types of graphitic carbon materials such as single-walled carbon nanotubes (SWNTs), graphene oxide (GO) and reduced graphene oxide (RGO). Scanning electron microscopy (SEM), fluorescence imaging and Raman spectroscopic results revealed that the graphitic carbon materials were selectively deposited on the surface of the periodic chitosan patterns by the electrostatic interaction between protonated amine groups of chitosan and the negative charged carbon materials. One proof-of-concept application of the system to the fabrication of electrical devices based on the micropatterns of SWNTs and RGO was also demonstrated. The strategy to use highly surface active chitosan pattern that can easily fabricate highly periodic pattern via a variety of lithographic tools may pave the way for the production of periodic arrays of graphitic carbon materials for large area device integration.


Assuntos
Quitosana/química , Eletrodos , Grafite/química , Impressão Molecular/métodos , Nanotubos de Carbono/química , Semicondutores , Cristalização/métodos , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Teste de Materiais , Nanotubos de Carbono/ultraestrutura , Óxidos/química , Tamanho da Partícula , Tensoativos/química
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