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1.
Int Psychogeriatr ; : 1-12, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623851

RESUMO

OBJECTIVES: Few studies have examined the impact of late-life depression trajectories on specific domains of cognitive function. This study aims to delineate how different depressive symptom trajectories specifically affect cognitive function in older adults. DESIGN: Prospective longitudinal cohort study. SETTING: Australia and the United States of America. PARTICIPANTS: In total, 11,035 community-dwelling older adults with a mean age of 75 years. MEASUREMENTS: Depressive trajectories were modelled from depressive symptoms according to annual Centre for Epidemiological Studies Depression Scale 10 (CES-D-10) surveys. Four trajectories of depressive symptoms were identified: low ("nondepressed"), consistently mild ("subthreshold depression"), consistently moderate ("persistent depression"), and initially low but increasing ("emerging depression"). Global cognition (Modified Mini-Mental State Examination [3MS]), verbal fluency (Controlled Oral Word Association Test [COWAT]), processing speed (Symbol Digit Modalities Test [SDMT]), episodic memory (Hopkins Verbal Learning Test - Revised [HVLT-R]), and a composite z-score were assessed over a subsequent median 2 years. RESULTS: Subthreshold depression predicted impaired performance on the SDMT (Cohen's d -0.04) and composite score (-0.03); emerging depression predicted impaired performance on the SDMT (-0.13), HVLT-R (-0.09), 3 MS (-0.08) and composite score (-0.09); and persistent depression predicted impaired performance on the SDMT (-0.08), 3 MS (-0.11), and composite score (-0.09). CONCLUSIONS: Depressive symptoms are associated with later impaired processing speed. These effects are small. Diverse depression trajectories have different impacts on cognitive function.

2.
Angew Chem Int Ed Engl ; 63(4): e202316662, 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38059768

RESUMO

Aryl-maleimides undergo a novel [2+4]-photodimerization instead of the expected [2+2]-photodimerization under both direct irradiation with visible light and under sensitized energy transfer conditions. This new excited state reactivity in aryl-maleimides is deciphered through photochemical, photophysical, and spectroscopic studies. The stereochemistry of the photodimer depends on the type of non-bonding interactions prevalent during photodimerization which is in turn dictated by the substituents on the maleimide ring. More importantly, the stereochemistry of the photodimer formed is complementary to the product observed under thermal conditions.

3.
Acta Psychiatr Scand ; 148(1): 47-59, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37157170

RESUMO

OBJECTIVE: Certain psychiatric disorders, including depression, appear to impact adversely on bone health. Anxiety disorders are highly prevalent but few studies have examined their effects on bone tissue. This study investigated the effect of anxiety disorders on bone mineral density (BMD). METHODS: This prospective cohort study used data from the Geelong Osteoporosis Study. Participants were women and men aged ≥20 years randomly selected from the electoral roll and followed up for a mean of 14.7 and 11.0 years, respectively. Participants were assessed for a lifetime history of an anxiety disorder using the Structured Clinical Interview for DSM-IV-TR. BMD in the lumbar spine and femoral neck was measured using dual-energy x-ray absorptiometry. RESULTS: Eight hundred and ninety women and 785 men participated in the study. Adjusting for sociodemographic, biometric and lifestyle factors, medical comorbidities and medication use, anxiety disorders were associated with reduced BMD at the lumbar spine (partial η2 = 0.006; p = 0.018) and femoral neck (partial η2 = 0.006; p = 0.003) in men. These associations became non-significant when men with a history of comorbid mood disorders were excluded from the analysis. There was no significant association between anxiety disorders and BMD in women (p ≥ 0.168). CONCLUSIONS: Anxiety disorders are associated with reduced BMD in men. This effect may be mediated by comorbid depression.


Assuntos
Densidade Óssea , Osteoporose , Masculino , Humanos , Feminino , Estudos Prospectivos , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Absorciometria de Fóton , Transtornos de Ansiedade/epidemiologia
4.
Acta Psychiatr Scand ; 147(1): 92-104, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36281968

RESUMO

BACKGROUND: Gerontology and ageing research are increasingly focussing on healthy life span (healthspan), the period of life lived free of serious disease and disability. Late-life depression (LLD) is believed to impact adversely on physical health. However, no studies have examined its effect on healthspan. This study investigated the effect of LLD and subthreshold depression on disability-free survival, a widely accepted measure of healthspan. METHODS: This prospective cohort study used data from the ASPirin in Reducing Events in the Elderly study. Participants were aged ≥70 years (or ≥65 years for African-American and Hispanic participants) and free of dementia, physical disability and cardiovascular disease. Depressive symptoms were measured using the 10-item Centre for Epidemiological Studies Depression Scale (CES-D-10). LLD and subthreshold depression were defined as CES-D-10 scores ≥8 and 3-7, respectively. Disability-free survival was defined as survival free of dementia and persistent physical disability. RESULTS: A total of 19,110 participants were followed up for a maximum of 7.3 years. In female participants, LLD was associated with lower disability-free survival adjusting for sociodemographic and lifestyle factors, medical comorbidities, polypharmacy, physical function and antidepressant use (HR, 1.50; 95% CI, 1.23-1.82). In male participants, LLD was associated with lower disability-free survival adjusting for sociodemographic and lifestyle factors (HR, 1.30; 95% CI, 1.03-1.64). Subthreshold depression was also associated with lower disability-free survival in both sexes. CONCLUSIONS: LLD may be a common and important risk factor for shortened healthspan.


Assuntos
Demência , Pessoas com Deficiência , Idoso , Humanos , Masculino , Feminino , Depressão/diagnóstico , Estudos Prospectivos , Antidepressivos/uso terapêutico , Demência/tratamento farmacológico
5.
Proc Natl Acad Sci U S A ; 117(9): 4921-4930, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32071223

RESUMO

Antibiotic-resistant superbug bacteria represent a global health problem with no imminent solutions. Here we demonstrate that the combination (termed AB569) of acidified nitrite (A-NO2-) and Na2-EDTA (disodium ethylenediaminetetraacetic acid) inhibited all Gram-negative and Gram-positive bacteria tested. AB569 was also efficacious at killing the model organism Pseudomonas aeruginosa in biofilms and in a murine chronic lung infection model. AB569 was not toxic to human cell lines at bactericidal concentrations using a basic viability assay. RNA-Seq analyses upon treatment of P. aeruginosa with AB569 revealed a catastrophic loss of the ability to support core pathways encompassing DNA, RNA, protein, ATP biosynthesis, and iron metabolism. Electrochemical analyses elucidated that AB569 produced more stable SNO proteins, potentially explaining one mechanism of bacterial killing. Our data implicate that AB569 is a safe and effective means to kill pathogenic bacteria, suggesting that simple strategies could be applied with highly advantageous therapeutic/toxicity index ratios to pathogens associated with a myriad of periepithelial infections and related disease scenarios.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ácido Edético/farmacologia , Nitrito de Sódio/farmacologia , Animais , Antibacterianos/uso terapêutico , Biofilmes/efeitos dos fármacos , Modelos Animais de Doenças , Regulação para Baixo , Farmacorresistência Bacteriana/efeitos dos fármacos , Ácido Edético/química , Pneumopatias/tratamento farmacológico , Pneumopatias/microbiologia , Redes e Vias Metabólicas , Camundongos , Nitritos/química , Nitritos/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos
6.
Australas Psychiatry ; 30(4): 526-529, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35560995

RESUMO

OBJECTIVE: The Better Health Access Initiative added 32 Medicare Benefits Schedule (MBS) item numbers in 2006 to increase the number of people with access to mental health care. We investigated trends in the provision of outpatient Medicare-subsidised psychiatric services since the introduction of these item numbers in 2006 through 2019. METHODS: Medicare Benefits Schedule aggregated item-number claims data were obtained from the Services Australia Medicare website, between January 2006 and December 2019 inclusive, for face-to-face psychiatrist consultations. Item number rates were collated and graphed per 100,000 population according to year and item number. RESULTS: There has been an increase in the number of claims for new patient assessments (291-296) and a reduction in most ongoing care Medicare item numbers, especially longer appointments that are often associated with psychotherapy provision (306-308). CONCLUSION: There have been changes in private psychiatric practice in Australia over the past 14 years. There are several possible causes for these changes and further research is required to determine the impact on patient care.


Assuntos
Pacientes Ambulatoriais , Psiquiatria , Idoso , Humanos , Programas Nacionais de Saúde , Prática Privada , Encaminhamento e Consulta
7.
Photochem Photobiol Sci ; 20(2): 255-263, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33721251

RESUMO

The photochemistry of Fe(III) coordinated to natural uronate-containing polysaccharides has been investigated quantitatively in aqueous solution. It is demonstrated that the photoreduction of the coordinated Fe(III) to Fe(II) and oxidative decarboxylation occurs in a variety of uronate-containing polysaccharides. The photochemistry of the Fe(III)-polyuronic acid system generated a radical species during the reaction which was studied using the spin trapping technique. The identity of the radical species from this reaction was confirmed as CO2•- indicating that both bond cleavage of the carboxylate and oxidative decarboxylation after ligand to metal charge transfer radical reactions may be taking place upon irradiation. Degradation of the polyuronic acid chain was investigated with dynamic light scattering, showing a decrease in the hydrodynamic radius of the polymer assemblies in solution after light irradiation that correlates with the Fe(II) generation. A decrease in viscosity of Fe(IIII)-alginate after light irradiation was also observed. Additionally, the photochemical reaction was investigated in plant root tissue (parsnip) demonstrating that Fe(III) coordination in these natural materials leads to photoreactivity that degrades the pectin component. These results highlight that this Fe(III)-polyuronic acid can occur in many natural systems and may play a role in biogeochemical cycling of iron and ferrous iron generation in plants with significant polyuronic acid content.

8.
Australas Psychiatry ; 29(3): 286-288, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32586111

RESUMO

OBJECTIVE: Injudicious use of medical imaging may be associated with harm to patients and increased downstream healthcare costs. Guidance on the use of imaging in common psychiatric inpatient scenarios is inconsistent or absent. This paper explores three common clinical scenarios facing adult psychiatrists and provides guidance about the appropriate use of imaging. CONCLUSION: Psychiatrists and their junior colleagues would benefit from considering both pre- and post-test probability in each presentation.


Assuntos
Diagnóstico por Imagem , Guias como Assunto , Pacientes Internados , Adulto , Humanos , Psiquiatria
9.
J Am Chem Soc ; 142(43): 18513-18521, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-32976712

RESUMO

The creation of ordered arrays of qubits that can be interfaced from the macroscopic world is an essential challenge for the development of quantum information science (QIS) currently being explored by chemists and physicists. Recently, porous metal-organic frameworks (MOFs) have arisen as a promising solution to this challenge as they allow for atomic-level spatial control of the molecular subunits that comprise their structures. To date, no organic qubit candidates have been installed in MOFs despite their structural variability and promise for creating systems with adjustable properties. With this in mind, we report the development of a pillared-paddlewheel-type MOF structure that contains 4,7-bis(2-(4-pyridyl)-ethynyl) isoindoline N-oxide and 1,4-bis(2-(4-pyridyl)-ethynyl)-benzene pillars that connect 2D sheets of 9,10-dicarboxytriptycene struts and Zn2(CO2)4 secondary binding units. The design allows for the formation of ordered arrays of reorienting isoindoline nitroxide spin centers with variable concentrations through the use of mixed crystals containing the secondary 1,4-phenylene pillar. While solvent removal causes decomposition of the MOF, magnetometry measurements of the MOF containing only N-oxide pillars demonstrated magnetic interactions with changes in magnetic moment as a function of temperature between 150 and 5 K. Variable-temperature electron paramagnetic resonance (EPR) experiments show that the nitroxides couple to one another at distances as long as 2 nm, but act independently at distances of 10 nm or more. We also use a specially designed resonance microwave cavity to measure the face-dependent EPR spectra of the crystal, demonstrating that it has anisotropic interactions with impingent electromagnetic radiation.

10.
J Am Chem Soc ; 142(1): 502-511, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31814397

RESUMO

Substituted triphenylamine (TPA) radical cations show great potential as oxidants and as spin-containing units in polymer magnets. Their properties can be further tuned by supramolecular assembly. Here, we examine how the properties of photogenerated radical cations, intrinsic to TPA macrocycles, are altered upon their self-assembly into one-dimensional columns. These macrocycles consist of two TPAs and two methylene ureas, which drive the assembly into porous organic materials. Advantageously, upon activation the crystals can undergo guest exchange in a single-crystal-to-single-crystal transformation generating a series of isoskeletal host-guest complexes whose properties can be directly compared. Photoinduced electron transfer, initiated using 365 nm light-emitting diodes, affords radicals at room temperature as observed by electron paramagnetic resonance (EPR) spectroscopy. The line shape of the EPR spectra and the quantity of radicals can be modulated by both polarity and heavy atom inclusion of the encapsulated guest. These photogenerated radicals are persistent, with half-lives between 1 and 7 d and display no degradation upon radical decay. Re-irradiation of the samples can restore the radical concentration back to a similar maximum concentration, a feature that is reproducible over several cycles. EPR simulations of a representative spectrum indicate two species, one containing two N hyperfine interactions and an additional broad signal with no resolvable hyperfine interaction. Intriguingly, TPA analogues without bromine substitution also exhibit similar quantities of photogenerated radicals, suggesting that supramolecular strategies can enable more flexibility in stable TPA radical structures. These studies will help guide the development of new photoactive materials.

11.
J Phys Chem A ; 124(37): 7411-7415, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32794775

RESUMO

Understanding factors that underpin the signs and magnitudes of electron spin-spin couplings in biradicaloids, especially those that are integrated into highly delocalized electronic structures, promises to inform the design of molecular spintronic systems. Using steady-state and variable temperature electron paramagnetic resonance (EPR) spectroscopy, we examine spin dynamics in symmetric, strongly π-conjugated bis[(porphinato)copper] (bis[PCu]) systems and probe the roles played by atom-specific macrocycle spin density, porphyrin-to-porphyrin linkage topology, and orbital symmetry on the magnitudes of electronic spin-spin couplings over substantial Cu-Cu distances. These studies examine the following: (i) meso-to-meso-linked bis[PCu] systems having oligoyne spacers, (ii) meso-to-meso-bridged bis[PCu] arrays in which the PCu centers are separated by a single ethynyl unit or multiple 5,15-diethynyl(porphinato)zinc(II) units, and (iii) the corresponding ß-to-ß-bridged bis[PCu] structures. EPR data show that, for ß-to-ß-bridged systems and meso-to-meso-linked bis[PCu] structures having oligoyne spacers, a through σ-bond coupling mechanism controls the average exchange interaction (Javg). In contrast, PCu centers separated by a single ethynyl or multiple 5,15-diethynyl(porphinato)zinc(II) units display a phenomenological decay of ln[Javg] versus Cu-Cu σ-bond separation number of ∼0.115 per bond, half as large as for these other compositions, congruent with the importance of π-mediated spin-spin coupling. These disparities derive from effects that trace their origin to the nature of the macrocycle-macrocycle linkage topology and the relative energy of the Cu dx2-y2 singly occupied molecular orbital within the frontier orbital manifold of these electronically delocalized structures. This work provides insight into approaches to tune the extent of spin exchange interactions and distance-dependent electronic spin-spin coupling magnitudes in rigid, highly conjugated biradicaloids.

12.
Intern Med J ; 50(1): 92-99, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-30989773

RESUMO

BACKGROUND: Junior doctors experience high rates of psychological distress and burnout. System-level interventions are one strategy to reduce psychological distress in junior doctors. Unfortunately, few of these interventions have been evaluated. AIM: To evaluate the acceptability and effectiveness of a resilience and well-being programme designed for junior doctors. METHODS: A prospective cohort study of 24 medical interns at a teaching hospital in regional Queensland with a control group of 29 medical interns at a second teaching hospital in regional Queensland. Survey instruments to assess psychological distress, the ProQOL and K10, were completed at baseline, at the completion of the well-being programme, and 3 months after the completion of the well-being programme at both sites. RESULTS: The intervention site had an older cohort and fewer participants had a regular general practitioner compared to the control site. Both groups had moderate levels of psychological distress. Insufficient numbers of participants completing the instruments at the two sites meant that it was not possible to demonstrate differences between the groups; however, the trends were promising. Qualitative evaluation data supported these trends, indicating that the Resilience on the Run programme was positively received and provided useful skills to junior doctors. CONCLUSION: Well-being programmes benefit medical interns; introducing new knowledge and skills for effectively identifying and managing personal and workplace stressors that can contribute to psychological distress.


Assuntos
Esgotamento Profissional/prevenção & controle , Internato e Residência/organização & administração , Corpo Clínico Hospitalar/psicologia , Saúde Ocupacional , Resiliência Psicológica , Adulto , Feminino , Hospitais de Ensino , Humanos , Satisfação no Emprego , Masculino , Pessoa de Meia-Idade , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Queensland , Inquéritos e Questionários , Adulto Jovem
16.
Aust N Z J Psychiatry ; 53(11): 1093-1104, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31113237

RESUMO

BACKGROUND: Australian and US guidelines recommend routine brain imaging, either computed tomography or magnetic resonance imaging, to exclude structural lesions in presentations for first-episode psychosis. The aim of this review was to examine the evidence for the appropriateness and clinical utility of this recommendation by assessing the frequency of abnormal radiological findings in computed tomography and magnetic resonance imaging scans among patients with first-episode psychosis. METHODS: PubMed and Embase database were searched from inception to April 2018 using appropriate MeSH or Emtree terms. Studies were included in the review if they reported data on computed tomography or magnetic resonance imaging scan findings of individuals with first-episode psychosis. No restriction on the geographical location of the study or the age of participants was applied. We calculated the percentage of abnormal radiological findings in each study, separately by the two diagnostic methods. RESULTS: There were 16 suitable studies published between 1988 and 2017, reporting data on an overall 2312 patients with first-episode psychosis. Most were observational studies with a retrospective design and the majority examined patients with computed tomography. While structural abnormalities were a relatively common finding, these rarely required clinical intervention (range across studies: 0-60.7%; median: 3.5%) and were very rarely the cause of the psychotic symptoms (range: 0-3.3%; median: 0%). Only 2 of the 16 studies concluded that brain imaging should be routinely ordered in first-episode psychosis. CONCLUSION: There is insufficient evidence to suggest that brain imaging should be routinely ordered for patients presenting with first-episode psychosis without associated neurological or cognitive impairment. The appropriate screening procedure for structural brain lesions is conventional history-taking, mental status and neurological examination. If intracranial pathology is suspected clinically, a magnetic resonance imaging or computed tomography scan should be performed depending on the clinical signs, the acuity and the suspected pathology. National guidelines should reflect evidence-based data.


Assuntos
Encéfalo/patologia , Transtornos Psicóticos/patologia , Humanos , Imageamento por Ressonância Magnética , Neuroimagem , Tomografia Computadorizada por Raios X
17.
Australas Psychiatry ; 32(1): 100, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38055499
18.
Australas Psychiatry ; 27(3): 212-214, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30293442

RESUMO

OBJECTIVE: To review selected literature available on trainee welfare and reflect on our own experiences to provide practical advice to our colleagues and suggest strategies to enhance trainee welfare. CONCLUSIONS: Promoting the welfare of psychiatry trainees requires a three-pronged approach. We must care for ourselves through individual strategies; we must advocate for optimization of the systems we work in to minimize modifiable factors associated with burnout; and we must continue on the perennial challenge of culture change to reduce stigma around stress and mental illness and promote a healthier workplace.


Assuntos
Esgotamento Profissional/prevenção & controle , Internato e Residência , Grupo Associado , Psiquiatria/educação , Pessoal de Saúde , Humanos , Resiliência Psicológica , Local de Trabalho/psicologia
20.
J Am Chem Soc ; 139(29): 9759-9762, 2017 07 26.
Artigo em Inglês | MEDLINE | ID: mdl-28578583

RESUMO

Spin and conformational dynamics in symmetric alkyne-bridged multi[copper(II) porphyrin] structures have been studied in toluene solution at variable temperature using steady-state electron paramagnetic resonance (EPR) spectroscopy. Comparison of the dimer EPR spectra to those of Cu porphyrin monomers shows evidence of an isotropic exchange interaction (Javg) in these biradicaloid structures, manifested by a significant line broadening in the dimer spectra. The extent line broadening depends on molecular structure and temperature, suggesting Javg is modulated by conformational dynamics that impact the torsional angle distribution between the porphyrin-porphyrin least-squares planes. Computational simulation of the experimental EPR spectra, using a developed algorithm for J modulation in flexible organic biradicals, supports this hypothesis. Comparison of ethyne and butadiyne alkyne bridges reveals remarkable sensitivity to orbital interactions between the spacer and the metal, reflected in measurements of Javg as a function of temperature. The results suggest orbital symmetry relationships may be more important than recognized in design of optimized molecular spintronic devices.

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