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1.
Sci Rep ; 13(1): 18237, 2023 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-37880240

RESUMO

Norbin is an adaptor protein that binds numerous G protein-coupled receptors (GPCRs), is highly expressed in neurons, and is essential for a functioning nervous system in rodent models. Yet, beyond its control of neurite outgrowth and synaptic plasticity, few cellular roles of Norbin have been investigated to date. Furthermore, while Norbin is known to regulate the steady-state cell surface levels of several GPCRs, only in one case has the protein been shown to control the agonist-induced receptor internalisation which serves to attenuate GPCR signalling. Here, we generated a Norbin-deficient PC12 cell line which enabled us to study both the cellular functions of Norbin and its roles in GPCR trafficking and signalling. We show that Norbin limits cell size and spreading, and is required for the growth, viability and cell cycle progression of PC12 cells. We also found that Norbin regulates both the steady-state surface level and agonist-induced internalisation of the GPCR sphingosine-1-phosphate receptor 1 (S1PR1) in these cells, suggesting that its role in agonist-dependent GPCR trafficking is more widespread than previously appreciated. Finally, we show that Norbin limits the S1P-stimulated activation of Akt and p38 Mapk, and is required for the activation of Erk in PC12 cells. Together, our findings provide a better understanding of the cellular functions of Norbin and its control of GPCR trafficking.


Assuntos
Receptores Acoplados a Proteínas G , Transdução de Sinais , Animais , Ratos , Ciclo Celular , Células PC12 , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Receptores de Esfingosina-1-Fosfato , Sobrevivência Celular/genética
2.
Front Neuroendocrinol ; 68: 101040, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36243109

RESUMO

Millions of women around the world use combined oral contraceptives (OCs), yet surprisingly little is known about their central nervous system (CNS) effects. This article provides a short overview of the basic pharmacology of OCs, emphasizing features that may be relevant to understanding their effects in the CNS. Historical and recent findings from studies of cognitive function, mood, and negative affect (depressive changes under OC use) are then reviewed. We also present data from an archival dataset from our own laboratory in which we explore dysphoric changes in women using four generations of contraceptive progestins. Current data in the field are consistent with a modest effect of OC use on CNS variables, but conclusions based on current findings must be made very cautiously because of multiple methodological issues in many published studies to date, and inconsistencies in the findings. Directions for future research over the next 10 years are suggested. (150 words).


Assuntos
Anticoncepcionais Orais Combinados , Progestinas , Feminino , Humanos , Anticoncepcionais Orais Combinados/farmacologia , Sistema Nervoso Central
3.
Front Endocrinol (Lausanne) ; 13: 888510, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36147581

RESUMO

The central nervous system effects of oral contraceptives (OCs) are not well-documented. In a set of 3 studies, we investigated a specific cognitive function, mental rotation, in healthy women currently using OCs for contraceptive purposes (n = 201) and in medication-free controls not using OCs (n = 44). Mental rotation was measured using a well-standardized and extensively validated psychometric test, the Vandenberg Mental Rotations Test (MRT). In an initial study (Study 1), current OC users (n = 63) were tested during the active or inactive phases of the contraceptive cycle in a parallel-groups design. Studies 2 and 3 were based on an archival dataset (n = 201 current OC users) that consisted of data on the MRT collected in real-time over a 30-year period and compiled for purposes of the present work. The OCs were combined formulations containing ethinyl estradiol (10-35 ug/day) plus a synthetic progestin. All 4 families of synthetic progestins historically used in OCs were represented in the dataset. Cognitive performance was evaluated during either active OC use ('active phase') or during the washout week of the contraceptive cycle ('inactive phase') when OC steroids are not used. The results showed a significant phase-of-cycle (POC) effect. Accuracy on the MRT was mildly diminished during the active phase of OC use, while scores on verbal fluency and speeded motor tasks were modestly improved. The POC effect was most evident in women using OCs that contained first- or second-generation progestins (the estrane family of progestins or OCs containing levonorgestrel), but not in women using OCs containing recently developed progestins and lower doses of ethinyl estradiol. Using independently established ratings of the estrogenic, androgenic, and progestogenic intensities of the different OC formulations, each brand of OC was classified according to its distinct endocrine profile. Multiple regression revealed that the effects of OC use on the MRT could be predicted based on the estrogenic strength of the contraceptives used. Estrogenic potency, not androgenic or anti-androgenic effects of the OC pill, may underlie the effects of OC usage on spatial cognition.


Assuntos
Levanogestrel , Progestinas , Cognição , Anticoncepcionais Orais/farmacologia , Estranos , Etinilestradiol/farmacologia , Feminino , Humanos , Congêneres da Progesterona , Progestinas/farmacologia
4.
Arch Womens Ment Health ; 25(2): 493-499, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35112165

RESUMO

Females show a small processing advantage relative to males in the ability to identify facial expressions of emotion. In laboratory studies, this is expressed as a sex difference in the accuracy of discrimination or in recognition latencies (the time required to identify an expression). Reasons for the sex difference are not well-understood. In the current pilot study, young adults (N = 62) with and without mild to moderate symptoms of depression were asked to discriminate facial images of infants and toddlers expressing six cardinal emotions. Results showed that elevated depressive affect was associated with more rapid recognition of negative emotions by females, and with potentiation of the typically observed sex difference, compared with non-depressed observers. Differences in endogenous affective status might be one proximate factor contributing to a female advantage in emotion recognition.


Assuntos
Depressão , Emoções , Depressão/diagnóstico , Depressão/psicologia , Expressão Facial , Feminino , Humanos , Masculino , Projetos Piloto , Reconhecimento Psicológico , Adulto Jovem
5.
Chem Soc Rev ; 51(1): 293-328, 2022 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-34889926

RESUMO

This review provides a comprehensive overview of recent advances in the supramolecular organisation and hierarchical self-assembly of organo-functionalised hybrid polyoxometalates (hereafter referred to as hybrid POMs), and their emerging role as multi-functional building blocks in the construction of new nanomaterials. Polyoxometalates have long been studied as a fascinating outgrowth of traditional metal-oxide chemistry, where the unusual position they occupy between individual metal oxoanions and solid-state bulk oxides imbues them with a range of attractive properties (e.g. solubility, high structural modularity and tuneable properties/reactivity). Specifically, the capacity for POMs to be covalently coupled to an effectively limitless range of organic moieties has opened exciting new avenues in their rational design, while the combination of distinct organic and inorganic components facilitates the formation of complex molecular architectures and the emergence of new, unique functionalities. Here, we present a detailed discussion of the design opportunities afforded by hybrid POMs, where fine control over their size, topology and their covalent and non-covalent interactions with a range of other species and/or substrates makes them ideal building blocks in the assembly of a broad range of supramolecular hybrid nanomaterials. We review both direct self-assembly approaches (encompassing both solution and solid-state approaches) and the non-covalent interactions of hybrid POMs with a range of suitable substrates (including cavitands, carbon nanotubes and biological systems), while giving key consideration to the underlying driving forces in each case. Ultimately, this review aims to demonstrate the enormous potential that the rational assembly of hybrid POM clusters shows for the development of next-generation nanomaterials with applications in areas as diverse as catalysis, energy-storage and molecular biology, while providing our perspective on where the next major developments in the field may emerge.


Assuntos
Nanoestruturas , Nanotubos de Carbono , Ânions , Polieletrólitos
6.
Cells ; 10(9)2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34572121

RESUMO

P-Rex1 is a guanine-nucleotide exchange factor (GEF) that activates Rac-type small G proteins in response to the stimulation of a range of receptors, particularly G protein-coupled receptors (GPCRs), to control cytoskeletal dynamics and other Rac-dependent cell responses. P-Rex1 is mainly expressed in leukocytes and neurons. Whereas its roles in leukocytes have been studied extensively, relatively little is known about its functions in neurons. Here, we used CRISPR/Cas9-mediated P-Rex1 deficiency in neuronal PC12 cells that stably overexpress the GPCR S1PR1, a receptor for sphingosine 1-phosphate (S1P), to investigate the role of P-Rex1 in neuronal GPCR signalling and cell responses. We show that P-Rex1 is required for the S1P-stimulated activation of Rac1 and Akt, basal Rac3 activity, and constitutive cAMP production in PC12-S1PR1 cells. The constitutive cAMP production was not due to increased expression levels of major neuronal adenylyl cyclases, suggesting that P-Rex1 may regulate adenylyl cyclase activity. P-Rex1 was required for maintenance of neurite protrusions and spreading in S1P-stimulated PC12-S1PR1 cells, as well as for cell-cycle progression and proliferation. In summary, we identified novel functional roles of P-Rex1 in neuronal Rac, Akt and cAMP signalling, as well as in neuronal cell-cycle progression and proliferation.


Assuntos
Ciclo Celular , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Neuritos/fisiologia , Neurônios/fisiologia , Receptores de Esfingosina-1-Fosfato/metabolismo , Animais , Movimento Celular , Proliferação de Células , Fatores de Troca do Nucleotídeo Guanina/antagonistas & inibidores , Fatores de Troca do Nucleotídeo Guanina/genética , Lisofosfolipídeos/metabolismo , Neurônios/citologia , Células PC12 , Ratos , Transdução de Sinais , Esfingosina/análogos & derivados , Esfingosina/metabolismo , Receptores de Esfingosina-1-Fosfato/antagonistas & inibidores , Receptores de Esfingosina-1-Fosfato/genética , Proteínas rac de Ligação ao GTP/genética , Proteínas rac de Ligação ao GTP/metabolismo , Proteínas rac1 de Ligação ao GTP/genética , Proteínas rac1 de Ligação ao GTP/metabolismo
7.
Blood Adv ; 5(16): 3076-3091, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34402884

RESUMO

Streptococcal pneumonia is a worldwide health problem that kills ∼2 million people each year, particularly young children, the elderly, and immunosuppressed individuals. Alveolar macrophages and neutrophils provide the early innate immune response to clear pneumococcus from infected lungs. However, the level of neutrophil involvement is context dependent, both in humans and in mouse models of the disease, influenced by factors such as bacterial load, age, and coinfections. Here, we show that the G protein-coupled receptor (GPCR) adaptor protein norbin (neurochondrin, NCDN), which was hitherto known as a regulator of neuronal function, is a suppressor of neutrophil-mediated innate immunity. Myeloid norbin deficiency improved the immunity of mice to pneumococcal infection by increasing the involvement of neutrophils in clearing the bacteria, without affecting neutrophil recruitment or causing autoinflammation. It also improved immunity during Escherichia coli-induced septic peritonitis. It increased the responsiveness of neutrophils to a range of stimuli, promoting their ability to kill bacteria in a reactive oxygen species-dependent manner, enhancing degranulation, phagocytosis, and the production of reactive oxygen species and neutrophil extracellular traps, raising the cell surface levels of selected GPCRs, and increasing GPCR-dependent Rac and Erk signaling. The Rac guanine-nucleotide exchange factor Prex1, a known effector of norbin, was dispensable for most of these effects, which suggested that norbin controls additional downstream targets. We identified the Rac guanine-nucleotide exchange factor Vav as one of these effectors. In summary, our study presents the GPCR adaptor protein norbin as an immune suppressor that limits the ability of neutrophils to clear bacterial infections.


Assuntos
Neutrófilos , Infecções Pneumocócicas , Animais , Camundongos , Camundongos Knockout , Neuropeptídeos , Receptores Acoplados a Proteínas G
8.
Psychoneuroendocrinology ; 129: 105239, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33951564

RESUMO

Circulating levels of testosterone (T) have been hypothesized to influence spatial cognition in adult men, but empirical support for this idea is mixed. Many of testosterone's effects are mediated by the classic nuclear androgen receptor (AR), which contains a polymorphic glutamine repeat (CAG repeat sequence) that varies significantly across individual men and confers differences in receptor function and therefore individual responsivity to T. We genotyped the AR CAG repeat length in 146 healthy adult men who also performed cognitive tests of mental rotation and spatial visualization. Circulating T concentrations were measured in saliva. CAG repeat length was found to be a significant predictor of spatial scores on tests of visualization but not mental rotation. A weaker AR was associated with lower visualization scores. In contrast, T itself, but not CAG repeat length predicted scores on two mental rotation tests. These results support the view that T action in the brain modestly influences spatial cognition in healthy men, but suggest that T's effects on mental rotation might not be AR-dependent and instead occur through an alternative mechanism.


Assuntos
Imaginação , Polimorfismo Genético , Receptores Androgênicos/genética , Rotação , Processamento Espacial , Adolescente , Humanos , Masculino , Receptores Androgênicos/metabolismo , Testosterona/metabolismo , Repetições de Trinucleotídeos/genética , Adulto Jovem
9.
Cereb Cortex ; 31(3): 1411-1426, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33124661

RESUMO

We present here the first evidence of the much-predicted double dissociation between the effect of stress on cognitive skills [executive functions (EFs)] dependent on prefrontal cortex (PFC) by catechol-O-methyltransferase (COMT) genotype. The COMT gene polymorphism with methionine (Met) at codon 158 results in more dopamine (DA) in PFC and generally better EFs, while with valine (Val) at codon 158 the result is less PFC DA and generally poorer EFs. Many have predicted that mild stress, by raising PFC DA levels should aid EFs of COMT-Vals (bringing their PFC DA levels up, closer to optimal) and impair EFs of COMT-Mets (raising their PFC DA levels past optimal). We tested 140 men and women in a within-subject crossover design using extremely mild social evaluative stress. On trials requiring EFs (incongruent trials) of the Flanker/Reverse Flanker task, COMT-Val158 homozygotes performed better when mildly stressed than when calmer, while COMT-Met158 carriers performed worse when mildly stressed. Two other teams previously tried to obtain this, but only found stress impairing EFs of COMT-Mets, not improving EFs of COMT-Vals. Perhaps we found both because we used a much milder stressor. Evidently, the bandwidth for stress having a facilitative effect on EFs is exceedingly narrow.


Assuntos
Catecol O-Metiltransferase/genética , Função Executiva/fisiologia , Córtex Pré-Frontal/fisiologia , Estresse Psicológico , Adulto , Feminino , Genótipo , Humanos , Masculino , Polimorfismo de Nucleotídeo Único
10.
Horm Behav ; 128: 104909, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33279507

RESUMO

Recent work has suggested that sex differences may exist in the strategies or types of cues that are utilized by men and women to remember discrete spatial locations or routes through a visual environment. The current study investigated the effects of circulating estradiol levels in women on the relative weighting of categorical versus fine-grained 'metric' information in a test of short-term memory for spatial locations, either presented within a simple geometric surround (a circular enclosure) or within more visually complex landscape scenes. Patterns of displacement error in the point location estimates made by men and women were analyzed. Results confirmed a sex difference in the weighting of metric versus categorical cues. Relative to men, women's estimates of locations were more strongly biased toward the center of the surrounding category (i.e., toward the category 'prototype'). Furthermore, objective measures of estradiol via saliva collected at the time of memory testing showed that, among naturally-cycling women, estradiol concentrations correlated in a positive, graded, fashion with the degree of emphasis that women placed on categorical information when estimating point locations. No associations were found for progesterone. These findings are consistent with a wider body of research showing that biological sex and reproductive hormone levels, including 17ß-estradiol, can subtly influence performance on certain spatial tasks. This is the first study to show that circulating estradiol levels may influence the relative emphasis placed on categorical versus metric cues when remembering simple point locations.


Assuntos
Estradiol , Percepção Espacial , Feminino , Humanos , Masculino , Rememoração Mental , Saliva , Memória Espacial
11.
J Clin Exp Neuropsychol ; 42(9): 881-901, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33023371

RESUMO

OBJECTIVE: Older adults with amnestic mild cognitive impairment (aMCI) develop Alzheimer's type dementia approximately 10 times faster annually than the normal population. Adrenal hormones are associated with aging and cognition. We investigated the relationship between acute stress, cortisol, and memory function in aMCI with an exploratory analysis of sex. METHOD: Salivary cortisol was sampled diurnally and during two test sessions, one session with the Trier Social Stress Test (TSST), to explore differences in the relationship between cortisol and memory function in age-normal cognition (NA) and aMCI. Participants with aMCI (n = 6 women, 9 men; mean age = 75) or similarly aged NA (n = 9 women, 7 men, mean age = 75) were given tests of episodic, associative, and spatial working memory with a psychosocial stressor (TSST) in the second session. RESULTS: The aMCI group performed worse on the memory tests than NA as expected, and males with aMCI had elevated cortisol levels on test days. Immediate episodic memory was enhanced by social stress in NA but not in the aMCI group, indicating that stress-induced alterations in memory are different in individuals with aMCI. High cortisol was associated with impaired performance on episodic memory in aMCI males only. Cortisol in Session 1 moderated the relationship with spatial working memory, whereby higher cortisol was associated with worse performance in NA, but better spatial working memory in aMCI. In addition, effects of aMCI on perceived anxiety in response to stress exposure were moderated by stress-induced cortisol in a sex-specific manner. CONCLUSIONS: We show effects of aMCI on Test Session cortisol levels and effects on perceived anxiety, and stress-induced impairments in memory in males with aMCI in our exploratory sample. Future studies should explore sex as a biological variable as our findings suggest that effects at the confluence of aMCI and stress can be obfuscated without sex as a consideration.


Assuntos
Doença de Alzheimer/sangue , Disfunção Cognitiva/sangue , Hidrocortisona/sangue , Memória Episódica , Caracteres Sexuais , Estresse Psicológico/sangue , Idoso , Envelhecimento/sangue , Envelhecimento/psicologia , Doença de Alzheimer/psicologia , Cognição/fisiologia , Disfunção Cognitiva/psicologia , Feminino , Humanos , Masculino , Memória de Curto Prazo/fisiologia , Testes Neuropsicológicos , Valores de Referência , Estresse Psicológico/complicações , Estresse Psicológico/psicologia
12.
Chem Commun (Camb) ; 56(59): 8237-8240, 2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32558835

RESUMO

An asymmetrically functionalised Wells-Dawson organic-inorganic hybrid polyoxometalate has been post-functionalised by Pt2+ coordination, and demonstrates self-assembly into surface-decorated micellar nanostructures. This multifunctional hybrid material is found to be a redox-active soft nanomaterial and demonstrates a new molecular design strategy with potential for applications in photo- or electro-catalysis.

13.
Neurobiol Aging ; 94: 1-6, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32497876

RESUMO

Oophorectomy prior to menopause is associated with late-life dementia. Memory decline may start within 6 months after oophorectomy in middle-aged women, suggested by lower verbal and working memory performance. Unknown is whether such changes persist beyond 6 months, and whether they are reversed by estradiol. Short-term benefits of estradiol on verbal memory following oophorectomy were observed in one study, but longer term effects remain unknown. In the present study, middle-aged BRCA1/2 mutation carriers with early oophorectomy at least 1 year prior to study onset were tested on verbal and working memory with results stratified by (1) current estradiol use (n = 22) or (2) no history of estradiol use (n = 24), and compared to age-matched premenopausal controls (n = 25). Both memory abilities were adversely affected by oophorectomy, but only working memory was maintained by estradiol. Estrogen metabolite levels correlated with working memory, suggesting a role for estradiol in preserving this ability. Memory decline appears to persist after early oophorectomy, particularly for women who do not take estradiol.


Assuntos
Cognição , Demência/etiologia , Menopausa , Salpingo-Ooforectomia/efeitos adversos , Adulto , Fatores Etários , Proteína BRCA2/genética , Demência/prevenção & controle , Demência/psicologia , Estradiol/administração & dosagem , Feminino , Heterozigoto , Humanos , Transtornos da Memória/etiologia , Transtornos da Memória/prevenção & controle , Transtornos da Memória/psicologia , Memória de Curto Prazo , Pessoa de Meia-Idade , Fatores de Tempo , Ubiquitina-Proteína Ligases/genética
14.
Angew Chem Int Ed Engl ; 59(34): 14331-14335, 2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32432351

RESUMO

We report the design and preparation of multifunctional hybrid nanomaterials through the stabilization of gold nanoparticles with thiol-functionalised hybrid organic-inorganic polyoxometalates (POMs). The covalent attachment of the hybrid POM forms new nanocomposites that are stable at temperatures and pH values which destroy analogous electrostatically functionalised nanocomposites. Photoelectrochemical analysis revealed the unique photochemical and redox properties of these systems.

15.
Psychoneuroendocrinology ; 115: 104488, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31899008

RESUMO

Sex differences in visuospatial cognition have long been reported, with men being advantaged on the Mental Rotations Test (MRT). The data, however, are variable, and sensitive to design parameters. When men and women are compared directly, with women in different hormonal milieus combined, there seem to be sex differences. When women alone are studied, taking into account different ovarian steroid concentrations and treatments, MRT performance varies with these changes. Indeed, several reports describe better performance among women with reduced estrogens. To better understand whether the sex difference in MRT persists once hormonal status is considered, we recruited reproductive age adults designated male and female at birth (MAB, FAB), and administered the Vandenberg-Kuse (V/K) MRT-comparing performance among MAB (n = 169) and FAB (n = 219). For FAB combined, we found a sex difference with MAB performing better than FAB. However, when FAB were analyzed by current menstrual cycle phase (Early Follicular (EF), Periovulatory (PO), Midluteal (ML)) or by hormone therapy (transmasculine testosterone administration (TM+), oral contraceptive (OC) ingestion prior to (OC+) or after cognitive testing (OC-)), low-estradiol groups (EF, OC-, TM+) performed as strongly as MAB, and had better MRT than cycling FAB in high-estradiol menstrual cycle phases (PO, ML). On a verbal memory control task, neither a sex difference nor a low estrogen advantage was detected, although performance varied with hormonal milieu. Our findings support a dynamic model of spatial performance and suggest that both MAB and FAB perform strongly on MRT, contingent on hormonal status.


Assuntos
Anticoncepcionais Orais/administração & dosagem , Estradiol/metabolismo , Ciclo Menstrual/fisiologia , Caracteres Sexuais , Percepção Espacial/fisiologia , Testosterona/administração & dosagem , Adulto , Feminino , Humanos , Imaginação/fisiologia , Masculino , Ciclo Menstrual/metabolismo , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adulto Jovem
16.
Horm Behav ; 119: 104655, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31843564

RESUMO

There is increasing evidence that reproductive hormones exert regulatory effects in the central nervous system that can influence behavioral, cognitive, perceptual, affective, and motivational processes. These effects occur in adults and post-pubertal individuals, and can be demonstrated in humans as well as laboratory animals. Large changes in 17ß-estradiol and progesterone occur over the ovarian cycle (i.e., the menstrual cycle) and afford a way for researchers to explore the central nervous system (CNS) effects of these hormones under natural physiological conditions. Increasingly, oral contraceptives are also being studied, both as another route to understanding the CNS effects of reproductive hormones and also as pharmacological agents in their own right. This mini-review will summarize the basic physiology of the menstrual cycle and essential facts about oral contraceptives to help novice researchers to use both paradigms effectively.


Assuntos
Pesquisa Comportamental/educação , Anticoncepcionais Orais/uso terapêutico , Endocrinologia/educação , Ciclo Menstrual/fisiologia , Adolescente , Adulto , Anticoncepcionais Orais/farmacologia , Educação Continuada , Feminino , Humanos , Masculino , Ciclo Menstrual/efeitos dos fármacos , Pesquisadores/educação , Adulto Jovem
17.
Angew Chem Int Ed Engl ; 58(50): 18281-18285, 2019 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-31595597

RESUMO

Access to asymmetrically functionalized polyoxometalates is a grand challenge as it could lead to new molecular nanomaterials with multiple or modular functionality. Now, a simple one-pot synthetic approach to the isolation of an asymmetrically functionalized organic-inorganic hybrid Wells-Dawson polyoxometalate in good yield is presented. The cluster bears two organophosphonate moieties with contrasting physical properties: a chelating metal-binding group, and a long aliphatic chain that facilitates solvent-dependent self-assembly into soft nanostructures. The orthogonal properties of the modular system are effectively demonstrated by controlled assembly of POM-based redox-active nanoparticles. This simple, high-yielding synthetic method is a promising new approach to the preparation of multi-functional hybrid metal oxide clusters, supermolecular systems, and soft-nanomaterials.

18.
J Clin Exp Neuropsychol ; 41(1): 87-107, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-29973120

RESUMO

INTRODUCTION AND OBJECTIVES: Many women report diminished memory function during the second or third trimesters of pregnancy, but objective neuropsychological tests often fail to show any decrement in performance. The present paper systematically reviews published studies that have investigated this phenomenon over the past 25 years and considers newer studies showing that affective changes occur during gestation in a subset of pregnant women. METHOD: A systematic search was conducted to identify articles relevant to pregnancy and memory function. Articles published since 1990 that included a nonpregnant comparison group were retained for review. RESULTS: A literature review of studies using objective memory testing suggests that a mild antepartum decline in explicit verbal recall occurs in some women. There is little empirical support for objective changes in semantic or implicit memory during pregnancy. Findings for working memory are mixed, with evidence supporting both decrements and enhancements. Inconsistencies in the literature potentially reflect a moderating influence of pregnancy-linked depressive affect on cognitive performance, not simply domain specificity, as previously suggested. CONCLUSIONS: Diminished memory function may occur in a specific subset of pregnant women who display depressive symptoms associated with pregnancy.


Assuntos
Afeto/fisiologia , Depressão/psicologia , Memória de Curto Prazo/fisiologia , Rememoração Mental/fisiologia , Gestantes/psicologia , Feminino , Humanos , Testes Neuropsicológicos , Gravidez , Terceiro Trimestre da Gravidez
19.
Curr Psychiatry Rep ; 20(12): 109, 2018 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-30306352

RESUMO

PURPOSE OF REVIEW: Working memory (WM) is a key process that is integral to many complex cognitive tasks, and it declines significantly with advancing age. This review will survey recent evidence supporting the idea that the functioning of the WM system in women is modulated by circulating estrogens. RECENT FINDINGS: In postmenopausal women, increased estrogen concentrations may be associated with improved WM function, which is evident on WM tasks that have a high cognitive load or significant manipulation demands. Experimental studies in rhesus monkeys and human neuroimaging studies support a prefrontal locus for these effects. Defining the basic neurochemical or cellular mechanisms that underlie the ability of estrogens to regulate WM is a topic of current research in both human and animal investigations. An emerging body of work suggests that frontal executive elements of the WM system are influenced by the circulating estrogen concentrations currently available to the CNS and that the effects are region-specific within the frontal cortex. These findings have implications for women's brain health and cognitive aging.


Assuntos
Envelhecimento/sangue , Envelhecimento/metabolismo , Estrogênios/sangue , Estrogênios/metabolismo , Memória de Curto Prazo/fisiologia , Animais , Encéfalo/fisiologia , Feminino , Humanos
20.
Soc Psychiatry Psychiatr Epidemiol ; 52(11): 1385-1394, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28821903

RESUMO

PURPOSE: We extend investigations of the impact of the content of video contact with an individual with schizophrenia on stigma reduction. We examine whether differential impacts persist over a 2-week period and the extent to which they are mediated by perceived similarity and feelings of empathy and/or sympathy. METHOD: We used a randomized control trial wherein participants were exposed to a video in which an individual described his recovery from schizophrenia, or the same person described acute symptoms of schizophrenia, or a no-video control condition. Outcomes included impressions of and preferred social distance to the person in the video and people in general with schizophrenia and well as perceptions of similarity and feelings of sympathy and empathy. We also measured an overt behaviour, seating distance, at 2-week follow-up. RESULTS: The recovery-focused material was generally more effective in improving impressions and reducing preferred level of social distance. Although the symptom-focused video resulted in great sympathy for the person, this did not translate into positive impressions or reduced social distance. Mediational analyses yielded findings consistent with the benefits of the recovery video being mediated by increased perceptions of similarity and lower feelings of sympathy. Exposure to the recovery-focused video resulted in less anxiety in anticipation of meeting the person in the video relative to the control condition. CONCLUSIONS: Video contact emphasizing potential for recovery from schizophrenia was more effective in reducing stigmatizing responses than contact highlighting acute symptoms. Increased sympathy does not necessarily translate into reductions in stigma.


Assuntos
Esquizofrenia/reabilitação , Psicologia do Esquizofrênico , Estigma Social , Adolescente , Adulto , Emoções , Empatia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Distância Psicológica , Gravação de Videoteipe , Adulto Jovem
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