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1.
Nature ; 613(7943): 280-286, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36631649

RESUMO

Macroscopic electric motors continue to have a large impact on almost every aspect of modern society. Consequently, the effort towards developing molecular motors1-3 that can be driven by electricity could not be more timely. Here we describe an electric molecular motor based on a [3]catenane4,5, in which two cyclobis(paraquat-p-phenylene)6 (CBPQT4+) rings are powered by electricity in solution to circumrotate unidirectionally around a 50-membered loop. The constitution of the loop ensures that both rings undergo highly (85%) unidirectional movement under the guidance of a flashing energy ratchet7,8, whereas the interactions between the two rings give rise to a two-dimensional potential energy surface (PES) similar to that shown by FOF1 ATP synthase9. The unidirectionality is powered by an oscillating10 voltage11,12 or external modulation of the redox potential13. Initially, we focused our attention on the homologous [2]catenane, only to find that the kinetic asymmetry was insufficient to support unidirectional movement of the sole ring. Accordingly, we incorporated a second CBPQT4+ ring to provide further symmetry breaking by interactions between the two mobile rings. This demonstration of electrically driven continual circumrotatory motion of two rings around a loop in a [3]catenane is free from the production of waste products and represents an important step towards surface-bound14 electric molecular motors.

2.
J Am Chem Soc ; 145(16): 9182-9190, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37042705

RESUMO

Near-infrared (NIR) light is known to have outstanding optical penetration in biological tissues and to be non-invasive to cells compared with visible light. These characteristics make NIR-specific light optimal for numerous biological applications, such as the sensing of biomolecules or in theranostics. Over the years, significant progress has been achieved in the synthesis of fluorescent cyclophanes for sensing, bioimaging, and making optoelectronic materials. The preparation of NIR-emissive porphyrin-free cyclophanes is, however, still challenging. In an attempt for fluorescence emissions to reach into the NIR spectral region, employing organic tetracationic cyclophanes, we have inserted two 9,10-divinylanthracene units between two of the pyridinium units in cyclobis(paraquat-p-phenylene). Steady-state absorption, fluorescence, and transient-absorption spectroscopies reveal the deep-red and NIR photoluminescence of this cyclophane. This tetracationic cyclophane is highly soluble in water and has been employed successfully as a probe for live-cell imaging in a breast cancer cell line (MCF-7).

3.
J Am Chem Soc ; 145(18): 10061-10070, 2023 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-37098077

RESUMO

Triplet-triplet annihilation-based molecular photon upconversion (TTA-UC) is a photophysical phenomenon that can yield high-energy emitting photons from low-energy incident light. TTA-UC is believed to fuse two triplet excitons into a singlet exciton through several consecutive energy-conversion processes. When organic aromatic dyes─i.e., sensitizers and annihilators─are used in TTA-UC, intermolecular distances, as well as relative orientations between the two chromophores, are important in an attempt to attain high upconversion efficiencies. Herein, we demonstrate a host-guest strategy─e.g., a cage-like molecular container incorporating two porphyrinic sensitizers and encapsulating two perylene emitters inside its cavity─to harness photon upconversion. Central to this design is tailoring the cavity size (9.6-10.4 Å) of the molecular container so that it can host two annihilators with a suitable [π···π] distance (3.2-3.5 Å). The formation of a complex with a host:guest ratio of 1:2 between a porphyrinic molecular container and perylene was confirmed by NMR spectroscopy, mass spectrometry, and isothermal titration calorimetry (ITC) as well as by DFT calculations. We have obtained TTA-UC yielding blue emission at 470 nm when the complex is excited with low-energy photons. This proof-of-concept demonstrates that TTA-UC can take place in one supermolecule by bringing together the sensitizers and annihilators. Our investigations open up some new opportunities for addressing several issues associated with supramolecular photon upconversion, such as sample concentrations, molecular aggregation, and penetration depths, which have relevance to biological imaging applications.

4.
Mol Psychiatry ; 27(3): 1339-1349, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34819636

RESUMO

The gabapentinoids, gabapentin, and pregabalin, target the α2δ subunits of voltage-gated calcium channels. Initially licensed for pain and seizures, they have become widely prescribed drugs. Many of these uses are off-label for psychiatric indications, and there is increasing concern about their safety, so it is particularly important to have good evidence to justify this usage. We conducted a systematic review and meta-analysis of the evidence for three of their common psychiatric uses: bipolar disorder, anxiety, and insomnia. Fifty-five double-blind randomised controlled trials (RCTs) and 15 open-label studies were identified. For bipolar disorder, four double-blind RCTs investigating gabapentin, and no double-blind RCTs investigating pregabalin, were identified. A quantitative synthesis could not be performed due to heterogeneity in the study population, design and outcome measures. Across the anxiety spectrum, a consistent but not universal effect in favour of gabapentinoids compared to placebo was seen (standardised mean difference [SMD] ranging between -2.25 and -0.25). Notably, pregabalin (SMD -0.55, 95% CI -0.92 to -0.18) and gabapentin (SMD -0.92, 95% CI -1.32 to -0.52) were more effective than placebo in reducing preoperative anxiety. In insomnia, results were inconclusive. We conclude that there is moderate evidence of the efficacy of gabapentinoids in anxiety states, but minimal evidence in bipolar disorder and insomnia and they should be used for these disorders only with strong justification. This recommendation applies despite the attractive pharmacological and genetic rationale for targeting voltage-gated calcium channels.


Assuntos
Transtorno Bipolar , Ácidos Cicloexanocarboxílicos , Distúrbios do Início e da Manutenção do Sono , Aminas/uso terapêutico , Ansiedade/tratamento farmacológico , Transtorno Bipolar/tratamento farmacológico , Canais de Cálcio , Ácidos Cicloexanocarboxílicos/uso terapêutico , Gabapentina/uso terapêutico , Humanos , Pregabalina/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Ácido gama-Aminobutírico/uso terapêutico
5.
Chem Soc Rev ; 51(20): 8450-8475, 2022 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-36189715

RESUMO

The year 2022 marks the 30th anniversary of the first reports of polyrotaxanes in the scientific literature. During the past three decades, many combinations of molecular rings and polymer chains have been synthesised and characterised. Until recently, however, the permutations of polyrotaxanes available to researchers were limited by synthetic methods which typically relied on an innate affinity between the molecular rings and polymer chains. With the advent of oligorotaxane-forming molecular pumps in 2015, it has now become possible to pump multiple rings against their will onto oligomer and polymer chains which have little or no affinity for the rings. These molecular pumps, which can recruit rings actively from solution to form precise polyrotaxanes, represent a major breakthrough in the field. This Tutorial Review highlights key milestones in the synthesis and investigation of polyrotaxanes along with recent developments in the synthesis and theory relating to molecular pumps. Polyrotaxane properties, arising from their topologies, have allowed them to steal a march on traditional polymers in a wide range of applications in materials, electronic and biological science, from slide-ring gels to robust coatings on cell phones, from molecular wires to flexible binders for battery anodes, from efficient multivalent protein binders to bio-cleavable polyplexes for cellular DNA delivery. Molecular pumps have the potential to blaze a contemporary trail for the synthesis of precise mechanically interlocked materials, especially those dependent on non-equilibrium chemistry and those related to energy storage and nanomedicine.


Assuntos
Rotaxanos , DNA/química , Polímeros/química , Rotaxanos/química
6.
J Am Chem Soc ; 144(37): 16898-16904, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36074552

RESUMO

Traditionally, the synthesis of polyrotaxanes has been limited by synthetic methods that rely on an innate affinity between the rings and the polymer chains. The use of rotaxane-forming molecular pumps allows this limitation to be circumvented in the production of non-equilibrium polyrotaxanes in which rings are trapped on polymer chains for which they have little or no affinity. Pumping cassettes, each composed of a bipyridinium unit linked (i) by a bismethylene bridge to a terminal 2,6-dimethylpyridinium cationic unit and (ii) by a methylene group to an isopropylphenylene steric barrier, were attached using copper-catalyzed azide-alkyne cycloadditions to the ends of a polypropylene glycol (PPG) chain of number-average molecular weight Mn ≈ 2200. Using a one-pot electrosynthetic protocol, a series of PPG-based polyrotaxanes with cyclobis(paraquat-p-phenylene) as the rings were synthesized. Despite the steric bulk of the PPG backbone, it was found to be a suitable collecting chain for threading up to 10 rings. The pumping of two rings is sufficient to render these hydrophobic polymers soluble in aqueous solution. Their hydrodynamic diameters and diffusion constants vary according to the number of pumped rings. The non-equilibrium nature of these polyrotaxanes is manifested in their gradual degradation and dethreading at elevated temperatures.


Assuntos
Rotaxanos , Alcinos , Azidas , Cobre/química , Paraquat , Polímeros/química , Propilenoglicóis , Rotaxanos/química
7.
J Am Chem Soc ; 144(37): 16841-16854, 2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36083184

RESUMO

Polar and polarizable π-conjugated organic molecules containing push-pull chromophores have been investigated extensively in the past. Identifying unique backbones and building blocks for fluorescent dyes is a timely exercise. Here, we report the synthesis and characterization of a series of fluorescent dyes containing quadrupolar A-D-A constitutions (where A = acceptor and D = donor), which exhibit fluorescence emission at a variety of different wavelengths. We have investigated the effects of different electron-withdrawing groups, located at both termini of a para-terphenylene backbone, by steady-state UV/vis and fluorescence spectroscopy. Pyridine and substituted pyridinium units are also introduced during the construction of the quadrupolar backbones. Depending on the quadrupolarity, fluorescence emission wavelengths cover from 380 to 557 nm. Time-resolved absorption and emission spectroscopy reveal that the photophysical properties of those quadrupolar dyes result from intramolecular charge transfer. One of the dyes we have investigated is a symmetrical box-like tetracationic cyclophane. Its water-soluble tetrachloride, which is non-cytotoxic to cells up to a loading concentration of 1 µM, has been employed in live-cell imaging. When taken up by cells, the tetrachloride emits a green fluorescence emission without any hint of photobleaching or disruption of normal cell behavior. We envision that our design strategy of modifying molecules through the functionalization of the quadrupolar building blocks as chromophores will lead to future generations of fluorescent dyes in which these A-D-A constitutional fragments are incorporated into more complex molecules and polymers for broader photophysical and biological applications.


Assuntos
Corantes Fluorescentes , Piridinas , Álcoois , Corantes Fluorescentes/química , Polímeros , Água
8.
BMC Psychiatry ; 22(1): 228, 2022 03 31.
Artigo em Inglês | MEDLINE | ID: mdl-35361184

RESUMO

BACKGROUND: People with substance use disorders may be at a greater risk of contracting COVID-19 infection and developing medical complications. Several institutional and governmental health agencies across the world developed ad hoc guidance for substance use disorder services and care of individuals misusing substances. We aimed to synthesise the best available recommendations on management and care of people with or at risk of substance use disorders during the COVID-19 pandemic from existing guidelines published in UK, USA, Australia, Canada, New Zealand, and Singapore. METHODS: We systematically searched existing guidelines and websites from 28 international institutions and governmental bodies in the context of the COVID-19 pandemic (May 4th 2021). We summarized the extracted data as answers to specific clinical questions. RESULTS: We organised the available recommendations from 19 sources in three sections. First, we focused on general advice and recommendations for people who misuse alcohol or drugs during the COVID-19 pandemic, the design of contingency plans, safeguarding issues for children and families of service users and advice to the public, patients, and carers. Then, we summarised specific guidelines for people who use illicit drugs and related services, such as opioid substitution treatment and needle and syringe programmes. Finally, we provided a synthesis on specific recommendations for services supporting people who misuse alcohol and key topics in the field, such as management of alcohol detoxification and safe transition between supervised and unsupervised consumption. CONCLUSIONS: Available guidance reflected different approaches, ranging from being extremely cautious in providing recommendations other than generic statements to proposing adaptation of previously available guidelines to confront the challenges of the COVID-19 pandemic. After the early phase, guidance focused on reduction of infection transmission and service delivery. Guidance did not provide advice on infection prevention via vaccination programmes and service access strategies tailored to individuals with substance use disorders.


Assuntos
Alcoolismo , COVID-19 , Transtornos Relacionados ao Uso de Substâncias , Alcoolismo/psicologia , Alcoolismo/terapia , Criança , Guias como Assunto , Pessoal de Saúde , Humanos , Pandemias , Transtornos Relacionados ao Uso de Substâncias/psicologia
9.
J Am Chem Soc ; 143(15): 5569-5591, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33830744

RESUMO

Pumps and motors are essential components of the world as we know it. From the complex proteins that sustain our cells, to the mechanical marvels that power industries, much we take for granted is only possible because of pumps and motors. Although molecular pumps and motors have supported life for eons, it is only recently that chemists have made progress toward designing and building artificial forms of the microscopic machinery present in nature. The advent of artificial molecular machines has granted scientists an unprecedented level of control over the relative motion of components of molecules through the development of kinetically controlled, away-from-thermodynamic equilibrium chemistry. We outline the history of pumps and motors, focusing specifically on the innovations that enable the design and synthesis of the artificial molecular machines central to this Perspective. A key insight connecting biomolecular and artificial molecular machines is that the physical motions by which these machines carry out their function are unambiguously in mechanical equilibrium at every instant. The operation of molecular motors and pumps can be described by trajectory thermodynamics, a theory based on the work of Onsager, which is grounded on the firm foundation of the principle of microscopic reversibility. Free energy derived from thermodynamically non-equilibrium reactions kinetically favors some reaction pathways over others. By designing molecules with kinetic asymmetry, one can engineer potential landscapes to harness external energy to drive the formation and maintenance of geometries of component parts of molecules away-from-equilibrium, that would be impossible to achieve by standard synthetic approaches.


Assuntos
Proteínas Motores Moleculares/metabolismo , Trifosfato de Adenosina/metabolismo , Catálise , Hidrólise , Cinética , Luz , Proteínas de Membrana Transportadoras/metabolismo , Modelos Moleculares , ATPases Translocadoras de Prótons/metabolismo , Termodinâmica
10.
Appl Opt ; 58(2): 353-360, 2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30645313

RESUMO

A new method for the analysis and design of fiber Bragg gratings (FBGs) based on the theory of transmission lines has been developed and verified both theoretically and experimentally. The method is an extension of the coupled-mode theory and utilizes the equivalent transmission lines in order to simulate any type of grating, with an easy and direct implementation. The method provides the ability to analyze the optical devices without using full wave approaches, while also facilitating the incorporation of core materials with a complex or non-linear refractive index, non-uniform distributions of the grating's refractive index, and tilted and phase-shifted gratings. The approach also allows the design of the grating for a given reflection spectra. Numerical results of the method's application on a randomly varied inscription of the refractive index of a FBG have also been simulated and discussed. Using this method, the characteristics of an erbium-doped (ED)-FBG have been simulated and the predictions verified experimentally.

11.
Eye Contact Lens ; 45(1): 40-45, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29944498

RESUMO

OBJECTIVES: To investigate the ocular surface of an aged population wearing a daily disposable contact lens (CL) over their 1st day of wear. METHODS: Forty eyes from 40 presbyopic subjects were fitted a daily CL (Delefilcon A). Tear osmolarity, tear meniscus area (TMA), and ocular surface aberrations (total higher-order root mean square [RMS]) were assessed at baseline (t0), at 20 min (t1) and after 8 hr (t2) of wear. Fluorescein corneal and conjunctival staining and tear breakup time (TBUT) were performed at t0 and t2. RESULTS: No statistically significant changes were found between t0, t1, and t2 for TMA and between t0 and t2 for fluorescein corneal and conjunctival staining. Tear breakup time worsened by the end of the day from 10.4±0.4 sec t0 to 9.0±0.3 sec t2 (P<0.05). Osmolarity showed significant changes between t0 306.9±2.3 mOsm/L and t1 312.4±2.4 mOsmol/L (P=0.02) but returned to baseline values at 8 hr (310.40±2.26 mOsm/L; P=0.09). Total higher-order RMS showed significant changes between t0 0.38±0.02 µm and t1 0.61±0.04 µm (P≤0.001) and between t0 and t2 0.64±0.41 µm (P≤0.001). CONCLUSIONS: Delefilcon A may induce measures changes (osmolarity and TBUT values) in a presbyopic population; however, TMA and vital staining were maintained at the baseline level over the day.


Assuntos
Envelhecimento/fisiologia , Lentes de Contato Hidrofílicas , Equipamentos Descartáveis , Síndromes do Olho Seco/terapia , Satisfação do Paciente , Presbiopia/terapia , Lágrimas/química , Adulto , Túnica Conjuntiva/metabolismo , Córnea/metabolismo , Síndromes do Olho Seco/metabolismo , Desenho de Equipamento , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Concentração Osmolar , Presbiopia/fisiopatologia , Estudos Prospectivos , Visão Ocular
12.
Appetite ; 108: 117-131, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27686818

RESUMO

Internationally, there is increasing recognition of the importance of multilevel policies and actions that address healthy and environmentally friendly food behaviours. However it is not yet clear which actions are most suitable to support consumers to adopt both behaviours concurrently. To this end, we undertook a qualitative study to assess consumer perceptions, experiences and attitudes towards healthy and environmentally friendly foods and four target behaviours: reducing overconsumption of food beyond energy needs, reducing consumption of low-nutrient energy dense foods, eating less animal- and more plant-derived foods, and reducing food waste. Online in-depth interviews were held with 29 Australian food shoppers representing different levels of involvement with health and environment in daily food choices. The results indicate that compared to health, the relationship between food and the environment is rarely considered by consumers. The four target food behaviours were primarily associated and motivated by an impact on health, except for not wasting foods. Participants had the most positive attitude and highest motivation for eating less processed and packaged foods, mostly to avoid excessive packaging and 'chemicals' in foods. This was followed by the behaviours reducing food waste and overconsumption. Conversely, there was a predominantly negative attitude towards, and low motivation for, eating less animal-derived products and more plant based foods. Overall, consumers found a joined concept of healthy and environmentally friendly foods an acceptable idea. We recommend that health should remain the overarching principle for policies and actions concerned with shifting consumer behaviours, as this personal benefit appears to have a greater potential to support behaviour change. Future consumer focused work could pay attention to framing behavioural messages, providing intermediate behavioural goals, and a multiple target approach to change habitual behaviours.


Assuntos
Conservação dos Recursos Naturais , Comportamento do Consumidor , Dieta Saudável , Preferências Alimentares , Abastecimento de Alimentos , Conhecimentos, Atitudes e Prática em Saúde , Participação Social , Adolescente , Adulto , Austrália , Pegada de Carbono , Conservação dos Recursos Naturais/economia , Comportamento do Consumidor/economia , Inquéritos sobre Dietas , Dieta Saudável/economia , Dieta Saudável/psicologia , Feminino , Aditivos Alimentares/efeitos adversos , Aditivos Alimentares/economia , Embalagem de Alimentos/economia , Preferências Alimentares/psicologia , Abastecimento de Alimentos/economia , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Motivação , Pesquisa Qualitativa , Adulto Jovem
13.
Can Vet J ; 57(8): 869-72, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27493288

RESUMO

A 14-year-old Quarter Horse was examined for a draining tract of 8 months' duration on the right mandible that was non-responsive to antibiotic therapy and surgical therapy. Further investigation and subsequent treatment with sialoendoscopy and ultrasonography were performed to relieve an obstruction of plant awns in the mandibular salivary duct.


Sialo-endoscopie comme traitement pour un canal salivaire mandibulaire bloqué chez un cheval. Un cheval Quarter Horse âgé de 14 ans a été examiné pour une fistule purulente d'une durée de 8 mois à la mandibule droite qui ne répondait pas à la thérapie antibiotique et à la thérapie chirurgicale. De nouvelles investigations et le traitement subséquent à l'aide de la sialo-endoscopie et de l'échographie ont été réalisés pour éliminer un blocage du canal salivaire mandibulaire par des barbes de plantes.(Traduit par Isabelle Vallières).


Assuntos
Endoscopia do Sistema Digestório/veterinária , Corpos Estranhos/veterinária , Doenças dos Cavalos/cirurgia , Mandíbula , Ductos Salivares , Doenças das Glândulas Salivares/veterinária , Animais , Drenagem/veterinária , Endoscopia do Sistema Digestório/métodos , Feminino , Corpos Estranhos/cirurgia , Doenças dos Cavalos/diagnóstico por imagem , Cavalos , Mandíbula/diagnóstico por imagem , Radiografia/veterinária , Ductos Salivares/diagnóstico por imagem , Ductos Salivares/cirurgia , Doenças das Glândulas Salivares/diagnóstico por imagem , Doenças das Glândulas Salivares/cirurgia
14.
BMJ Ment Health ; 26(1)2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37567731

RESUMO

BACKGROUND: Worldwide uptake of telepsychiatry accelerated during the COVID-19 pandemic. OBJECTIVE: To conduct an evaluation of the opinions, preferences and attitudes to telepsychiatry from service users, carers and clinicians in order to understand how telepsychiatry can be best used in the peri/post-COVID-19 era. METHODS: This mixed-methods, multicentre, international study of telepsychiatry was set in two sites in England and two in Italy. Survey questionnaires and focus group topic guides were co-produced for each participant group (service users, carers and clinicians). FINDINGS: In the UK, 906 service users, 117 carers and 483 clinicians, and in Italy, 164 service users, 56 carers and 72 clinicians completed the surveys. In all, 17 service users/carers and 14 clinicians participated in focus groups. Overall, telepsychiatry was seen as convenient in follow-ups with a specific purpose such as medication reviews; however, it was perceived as less effective for establishing a therapeutic relationship or for assessing acutely disturbed mental states. In contrast to clinicians, most service users and carers indicated that telepsychiatry had not improved during the COVID-19 pandemic. Most service users and carers reported that the choice of appointment modality was most often determined by the service or clinician. CONCLUSION AND RELEVANCE: There were circumstances in which telepsychiatry was seen as more suitable than others and clear differences in clinician, carer and service user perspectives on telepsychiatry. CLINICAL IMPLICATIONS: All stakeholders should be actively engaged in determining a hybrid model of care according to clinical features and service user and carer preferences. Clinicians should be engaged in training programmes on telepsychiatry.


Assuntos
COVID-19 , Psiquiatria , Telemedicina , Humanos , Cuidadores , Pandemias , COVID-19/epidemiologia
15.
JMIR Ment Health ; 9(8): e38600, 2022 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-35994310

RESUMO

BACKGROUND: The COVID-19 pandemic required mental health services around the world to adapt quickly to the new restrictions and regulations put in place to reduce the risk of transmission. As face-to-face contact became difficult, virtual methods were implemented to continue to safely provide mental health care. However, it is unclear to what extent service provision transitioned to telemental health worldwide. OBJECTIVE: We aimed to systematically review the global research literature on how mental health service provision adapted during the first year of the pandemic. METHODS: We searched systematically for quantitative papers focusing on the impact of the COVID-19 pandemic on mental health services published until April 13, 2021, in the PubMed, Embase, medRxiv, and bioXriv electronic bibliographic databases, using the COVID-19 Open Access Project online platform. The screening process and data extraction were independently completed by at least two authors, and any disagreement was resolved by discussion with a senior member of the team. The findings were summarized narratively in the context of each country's COVID-19 Stringency Index, which reflects the stringency of a government's response to COVID-19 restrictions at a specific time. RESULTS: Of the identified 24,339 records, 101 papers were included after the screening process. Reports on general services (n=72) showed that several countries' face-to-face services reduced their activities at the start of the pandemic, with reductions in the total number of delivered visits and with some services forced to close. In contrast, telemental health use rapidly increased in many countries across the world at the beginning of the pandemic (n=55), with almost complete virtualization of general and specialistic care services by the end of the first year. Considering the reported COVID-19 Stringency Index values, the increased use of virtual means seems to correspond to periods when the Stringency Index values were at their highest in several countries. However, due to specific care requirements, telemental health could not be used in certain subgroups of patients, such as those on clozapine or depot treatments and those who continued to need face-to-face visits. CONCLUSIONS: During the pandemic, mental health services had to adapt quickly in the short term, implementing or increasing the use of telemental health services across the globe. Limited access to digital means, poor digital skills, and patients' preferences and individual needs may have contributed to differences in implementing and accessing telemental health services during the pandemic. In the long term, a blended approach, combining in-person and virtual modalities, that takes into consideration the needs, preferences, and digital skills of patients may better support the future development of mental health services. It will be required to improve confidence with digital device use, training, and experience in all modalities for both clinicians and service users.

16.
Science ; 371(6525)2021 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-33414190

RESUMO

Phillips et al (Reports, 25 October 2019, p. 480) incorrectly conclude that tropical earthworm communities are less diverse and abundant than temperate communities. This result is an artifact generated by some low-quality datasets, lower sampling intensity in the tropics, different patterns in richness-area relationships, the occurrence of invasive species in managed soils, and a focus on local rather than regional richness.


Assuntos
Oligoquetos , Animais , Solo
17.
Science ; 374(6572): 1215-1221, 2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34672694

RESUMO

Over the past century, adsorption has been investigated extensively in equilibrium systems, with a focus on the van der Waals interactions associated with physisorption and electronic interactions in the case of chemisorption. In this study, we demonstrate mechanisorption, which results from nonequilibrium pumping to form mechanical bonds between the adsorbent and the adsorbate. This active mode of adsorption has been realized on surfaces of metal-organic frameworks grafted with arrays of molecular pumps. Adsorbates are transported from one well-defined compartment, the bulk, to another well-defined compartment, the interface, thereby creating large potential gradients in the form of chemical capacitors wherein energy is stored in metastable states. Mechanisorption extends, in a fundamental manner, the scope and potential of adsorption phenomena and offers a transformative approach to control chemistry at surfaces and interfaces.

18.
J Cataract Refract Surg ; 34(8): 1329-38, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18655984

RESUMO

PURPOSE: To determine whether letter sequences and/or lens-presentation order should be randomized when measuring defocus curves and to assess the most appropriate criterion for calculating the subjective amplitude of accommodation (AoA) from defocus curves. SETTING: Eye Clinic, School of Life & Health Sciences, Aston University, Birmingham, United Kingdom. METHODS: Defocus curves (from +3.00 diopters [D] to -3.00 D in 0.50 D steps) for 6 possible combinations of randomized or nonrandomized letter sequences and/or lens-presentation order were measured in a random order in 20 presbyopic subjects. Subjective AoA was calculated from the defocus curves by curve fitting using various published criteria, and each was correlated to subjective push-up AoA. Objective AoA was measured for comparison of blur tolerance and pupil size. RESULTS: Randomization of lens-presentation order and/or letter sequences, or lack of, did not affect the measured defocus curves (P >.05, analysis of variance). The range of defocus that maintains highest achievable visual acuity (allowing for variability of repeated measurement) was better correlated to (r = 0.84) and agreed best with (+/-0.50 D) subjective push-up AoA than any other relative or absolute acuity criterion used in previous studies. CONCLUSIONS: Nonrandomized letters and lens presentation on their own did not affect subjective AoA measured by defocus curves, although their combination should be avoided. Quantification of subjective AoA from defocus curves should be standardized to the range of defocus that maintains the best achievable visual acuity.


Assuntos
Acomodação Ocular/fisiologia , Hiperopia/fisiopatologia , Miopia/fisiopatologia , Presbiopia/diagnóstico , Presbiopia/fisiopatologia , Humanos , Pessoa de Meia-Idade , Pupila/fisiologia , Distribuição Aleatória , Testes Visuais , Acuidade Visual/fisiologia
19.
Clin Rev Allergy Immunol ; 32(1): 97-110, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17426365

RESUMO

Acetylsalicylic acid (ASA) or aspirin and nonsteroidal anti-inflammatory drug (NSAID) sensitivities encompass a diverse group of both pharmacological and hypersensitivity reactions. Conventionally, hypersensitivities include aspirin-exacerbated respiratory disease (AERD), ASA-induced urticaria, and anaphylaxis. With an increasing prevalence of coronary artery disease in an aging population, aspirin continues to play a significant role in cardiac prophylaxis in a large patient population. Invariably, the clinician will encounter patients with clear indications for aspirin therapy but a history of aspirin sensitivity. Although protocols have been established for aspirin challenge and desensitization, it is not always an efficacious or safe procedure. This article reviews the different classifications of ASA/NSAIDs hypersensitivities to better guide the clinician in dealing with this patient population. History of crossrelativities between multiple NSAIDs implies a non-IgE-mediated process. Similarly, a history of monosensitivity to one NSAID implies an IgE-mediated process, although specific antibodies are often elusive. Despite the name, AERD can potentially be exacerbated by all cyclooxygenase (COX) inhibitors based on dose-dependent inhibition of COX-1. Aspirin desensitization can be achieved to improve both upper and lower respiratory symptoms for most patient with AERD. Aspirin desensitization can usually be achieved for those in need of the antiplatelet effects of aspirin, with the exception of those with aspirin-induced urticaria and baseline chronic urticaria. However, desensitization should only be attempted in those with stable coronary artery disease because the process of desensitization carries the inherent risk of anaphylaxis/anaphylactoid reaction, which may further increase cardiac demand and bring about ischemic injury. Therefore, desensitization is reserved until coronary artery disease is stabilized.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Aspirina/efeitos adversos , Hipersensibilidade a Drogas/imunologia , Hipersensibilidade a Drogas/patologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Aspirina/farmacologia , Humanos , Urticária/induzido quimicamente , Urticária/patologia
20.
Autoimmun Rev ; 5(7): 471-85, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16920574

RESUMO

In recent years, an explosion of biologic response modifiers has entered the market to combat a variety of immune-mediated diseases. These can be in the form of recombinant cytokines, as in the case of interferon beta in the treatment of multiple sclerosis, or novel engineered antibodies constructed by combining non-human determinants with a human immunoglobulin scaffold, as in the case of omalizumab in the treatment of allergic asthma. More recently, completely human monoclonal antibodies have also been constructed. Adverse reactions related to these agents can be classified as expected or unexpected events. A number of case studies and a handful of randomized trials have demonstrated the potential toxicities with the use of biologic response modifiers. This article aims to review adverse event profiles of select biologic response modifiers for which the most data is available and are common to a rheumatology, allergy/immunology, and dermatology patient population.


Assuntos
Doenças do Sistema Imunitário/tratamento farmacológico , Fatores Imunológicos/efeitos adversos , Fatores Imunológicos/uso terapêutico , Animais , Citocinas/antagonistas & inibidores , Humanos
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