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1.
J Biol Inorg Chem ; 28(6): 531-547, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37458856

RESUMO

In the treatment of hormone-dependent cancers, aromatase inhibitors (AI) are receiving increased attention due to some undesirable effects such as the risk of endometrial cancer and thromboembolism of SERMs (selective estrogen receptor modulators). Letrozole is the most active AI with 99% aromatase inhibition. Unfortunately, this compound also exhibits some adverse effects such as hot flashes and fibromyalgias. Therefore, there is an urgent need to explore new types of AIs that retain the same-or even increased-antitumor ability. Inspired by the letrozole structure, a set of new derivatives has been synthesized that include a ferrocenyl moiety and different heterocycles. The derivative that contains a benzimidazole ring, namely compound 6, exhibits a higher aromatase inhibitory activity than letrozole and it also shows potent cytostatic behavior when compared to other well-established aromatase inhibitors, as demonstrated by dose-response, cell cycle, apoptosis and time course experiments. Furthermore, 6 promotes the inhibition of cell growth in both an aromatase-dependent and -independent fashion, as indicated by the study of A549 and MCF7 cell lines. Molecular docking and molecular dynamics calculations on the interaction of 6 or letrozole with the aromatase binding site revealed that the ferrocene moiety increases the van der Waals and hydrophobic interactions, thus resulting in an increase in binding affinity. Furthermore, the iron atom of the ferrocene fragment can form a metal-acceptor interaction with a propionate fragment, and this results in a stronger coupling with the heme group-a possibility that is consistent with the strong aromatase inhibition of 6.


Assuntos
Neoplasias da Mama , Citostáticos , Humanos , Feminino , Letrozol/farmacologia , Inibidores da Aromatase/farmacologia , Inibidores da Aromatase/química , Aromatase/metabolismo , Metalocenos , Simulação de Acoplamento Molecular , Nitrilas/farmacologia , Triazóis/farmacologia , Células MCF-7
2.
Molecules ; 28(12)2023 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-37375189

RESUMO

A new series of donor-acceptor-donor (D-A-D) structures derived from arylethynyl 1H-benzo[d]imidazole was synthesized and processed into single crystals with the goal of testing such crystals' ability to act as optical waveguides. Some crystals displayed luminescence in the 550-600 nm range and optical waveguiding behavior with optical loss coefficients around 10-2 dB/µm, which indicated a notable light transport. The crystalline structure, confirmed by X-ray diffraction, contains internal channels that are important for light propagation, as we previously reported. The combination of a 1D assembly, a single crystal structure, and notable light emission properties with low losses from self-absorption made 1H-benzo[d]imidazole derivatives appealing compounds for optical waveguide applications.

3.
Gastroenterol Hepatol ; 46(2): 83-91, 2023 Feb.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35278503

RESUMO

BACKGROUND AND OBJECTIVES: The main clinical practice guidelines recommend adequate periprocedural withdrawal and reintroduction of antithrombotic drugs in case of invasive techniques. The main objective of this study was to assess whether, in patients receiving anticoagulant or antiplatelet therapy, the suppression or reduction of the pharmacological dose for the performance of endoscopic retrograde cholangiopancreatography (ERCP) implies a greater risk of thromboembolic events. PATIENTS AND METHODS: A prospective observational study was carried out, which included 644ERCP performed with therapeutic intention during 2019 at the Reina Sofía University Hospital with follow-up during the 30days after the endoscopic intervention. RESULTS: Six patients presented a thromboembolic event, finding no differences between the incorrect withdrawal/reintroduction of antithrombotic treatment and a higher proportion of thromboembolic or hemorrhagic events after the procedure (P>.05). The incidence of thrombotic events was significantly higher in patients treated with heparin or apixaban (P=.001), as well as with a history of atrial fibrillation (P=.05), rheumatic valve disease (P=.037) and recurrent pulmonary embolism (P=.035), this being also an independent risk factor. Likewise, the incidence of hemorrhage in the 30days post-sphincterotomy was significantly lower in those with implantation of a biliary prosthesis (P=.04). CONCLUSIONS: Inadequate periprocedural management of antithrombotic therapy is not associated with a significant increase in the incidence of thromboembolic events in the 30days after ERCP. However, close follow-up and surveillance during the days after this is essential in those patients with a condition that significantly increases the risk of thrombosis.


Assuntos
Tromboembolia , Trombose , Humanos , Anticoagulantes/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/métodos , Fibrinolíticos/efeitos adversos , Tromboembolia/epidemiologia , Tromboembolia/etiologia , Tromboembolia/prevenção & controle , Hemorragia/etiologia , Trombose/etiologia
4.
Rev Endocr Metab Disord ; 23(1): 13-30, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34523036

RESUMO

Leptin is a hormone primarily produced by the adipose tissue in proportion to the size of fat stores, with a primary function in the control of lipid reserves. Besides adipose tissue, leptin is also produced by other tissues, such as the stomach, placenta, and mammary gland. Altogether, leptin exerts a broad spectrum of short, medium, and long-term regulatory actions at the central and peripheral levels, including metabolic programming effects that condition the proper development and function of the adipose organ, which are relevant for its main role in energy homeostasis. Comprehending how leptin regulates adipose tissue may provide important clues to understand the pathophysiology of obesity and related diseases, such as type 2 diabetes, as well as its prevention and treatment. This review focuses on the physiological and long-lasting regulatory effects of leptin on adipose tissue, the mechanisms and pathways involved, its main outcomes on whole-body physiological homeostasis, and its consequences on chronic diseases.


Assuntos
Diabetes Mellitus Tipo 2 , Leptina , Tecido Adiposo/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Homeostase , Humanos , Obesidade/metabolismo
5.
Future Oncol ; 18(25): 2843-2856, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35801416

RESUMO

Aim: This study aimed to assess physician preferences for later lines (third to fifth) of therapy in patients with relapsed/refractory multiple myeloma (RRMM) in the USA. Materials & methods: Factors relevant to physicians' treatment preferences for RRMM were identified from a literature search and refined in a qualitative phase. Preferences were quantitatively assessed using a discrete choice experiment. Physicians (n = 227) made choices regarding treatment scenarios for RRMM. Results: Efficacy had the highest mean relative importance, with overall survival valued as most important when making treatment decisions for patients with RRMM. Reduced incidences of keratopathy and thrombocytopenia had similar relative importance in later-line treatment. Conclusion: Greater understanding of physicians' criteria for clinical decision-making may help inform wider adoption of new treatments.


When deciding which treatment patients with relapsed or refractory multiple myeloma should receive, physicians have to weigh the benefits of each treatment against the risk of side effects. This study required physicians to complete a survey on aspects involved in their treatment decisions and identified those of highest importance. Physicians chose patient survival as the most important factor and minimization of side effects as less important considerations. Reducing patients' risk of developing corneal conditions or low platelet (a type of blood cell) count were of equal importance to doctors. Understanding physicians' treatment preferences and the reasons behind them will help identify gaps in education about new therapies as they become available.


Assuntos
Mieloma Múltiplo , Médicos , Tomada de Decisão Clínica , Tomada de Decisões , Humanos , Mieloma Múltiplo/tratamento farmacológico
6.
Child Dev ; 93(1): 254-268, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34463360

RESUMO

National-level monitoring of quality of early childhood education (ECE) is key to achieving inclusive and equitable education. Most countries report structural quality while process characteristics are rarely observed at the national level. This study examined the associations between ECE and children's development in a middle-income country using data from a nationally representative sample of public centers serving Colombian children (N = 3163; M = 4.3 years, 50% girls; 42% Mestizo, 16% White, 15% Afro-Colombian, 4% Indigenous, 23% not reported). Descriptive findings evidenced low to moderate quality. Multilevel models showed several positive associations between structural and process quality and child outcomes. Results have implications for the existing literature and highlight the feasibility of quality monitoring in low- and middle-income countries.


Assuntos
Desenvolvimento Infantil , Renda , Criança , Pré-Escolar , Colômbia , Escolaridade , Feminino , Humanos , Masculino
7.
Curr Opin Anaesthesiol ; 35(6): 728-732, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36194145

RESUMO

PURPOSE OF REVIEW: The penalization of error in the health field continues to be one of the main barriers in the notification, analysis and proposals for measures to improve adverse events. Strategies should be established in order to develop a nonpunitive culture with the sole purpose of learning from mistakes and improving patient safety. RECENT FINDINGS: Strategies are established for the development of a nonpunitive culture, such as promoting confidentiality and data protection in the notification and analysis of adverse events. SUMMARY: Despite education, improvements in quality and safety in healthcare, mistakes will undoubtedly occur. The creation of a protected, blame-free environment that promotes systematic reporting of adverse events will provide valuable information for preventive work and the desired improvement in patient and health team safety.


Assuntos
Erros Médicos , Segurança do Paciente , Humanos , Erros Médicos/prevenção & controle , Atenção à Saúde , Gestão da Segurança
8.
Aten Primaria ; 54(12): 102501, 2022 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-36375295

RESUMO

INTRODUCTION: Primary care (PC) is the first contact between the patient and the doctor, so it is essential to be clear about the criteria for suspecting a genetic disease and where it should be referred for study. MATERIAL AND METHODS: Four scientific societies: the Spanish Society of Family and Community Medicine (semFYC), the Spanish Association of Human Genetics (AEGH), the Spanish Association of Pediatrics (AEP) and the Spanish Society of Medical Oncology (SEOM), have reviewed the criteria for referral to the clinical genetics services of the different published guidelines with the purpose of define the recommendations for PC. CONCLUSIONS: With this consensus document, the PC doctor and pediatrician will know when, how and where to refer their patients with hereditary and/or genetic pathology to clinical genetics services.


Assuntos
Medicina Comunitária , Encaminhamento e Consulta , Humanos , Criança , Consenso , Atenção Primária à Saúde , Espanha
9.
Adv Appl Microbiol ; 114: 37-72, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33934852

RESUMO

Yeasts and humans have had a close relationship for millenia. Yeast have been used for food production since the first human societies. Since then, alternative uses have been discovered. Nowadays, antibiotic resistance constitutes a pressing need worldwide. In order to overcome this threat, one of the most important strategies is the search for new antimicrobials in natural sources. Moreover, biopreservation based on natural sources has emerged as an alternative to more common chemical preservatives. Yeasts constitute an underexploited source of antagonistic activity against other microorganisms. Here, we compile a summary of the antagonistic activity of yeast origin against other yeast and other microorganisms, such as bacteria or parasites. We present the mechanisms of action used by yeasts to display these activities. We also provide applications of these antagonistic activities in food industry and agriculture, medicine and veterinary, where yeast promise to play a pivotal role in the near future.


Assuntos
Anti-Infecciosos , Leveduras , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Bactérias/genética , Conservantes de Alimentos , Humanos , Saccharomyces cerevisiae
10.
Angew Chem Int Ed Engl ; 60(3): 1450-1457, 2021 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-33119950

RESUMO

Pickering emulsion systems have emerged as platforms for the synthesis of organic molecules in biphasic biocatalysis. Herein, the catalytic performance was evaluated for biotransformation using whole cells exemplified for the dehydration of n-octanaloxime to n-octanenitrile catalysed by an aldoxime dehydratase (OxdB) overexpressed in E. coli. This study was carried out in Pickering emulsions stabilised solely with silica particles of different hydrophobicity. We correlate, for the first time, the properties of the emulsions with the conversion of the reaction, thus gaining an insight into the impact of the particle wettability and particle concentration. When comparing two emulsions of different type with similar stability and droplet diameter, the oil-in-water (o/w) system displayed a higher conversion than the water-in-oil (w/o) system, despite the conversion in both cases being higher than that in a "classic" two-phase system. Furthermore, an increase in particle concentration prior to emulsification resulted in an increase of the interfacial area and hence a higher conversion.


Assuntos
Desidratação/enzimologia , Biocatálise , Emulsões , Humanos , Molhabilidade
11.
Clin Infect Dis ; 70(2): 181-190, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30843046

RESUMO

BACKGROUND: The incidence of herpes zoster is up to 9 times higher in immunosuppressed solid organ transplant recipients than in the general population. We investigated the immunogenicity and safety of an adjuvanted recombinant zoster vaccine (RZV) in renal transplant (RT) recipients ≥18 years of age receiving daily immunosuppressive therapy. METHODS: In this phase 3, randomized (1:1), observer-blind, multicenter trial, RT recipients were enrolled and received 2 doses of RZV or placebo 1-2 months (M) apart 4-18M posttransplant. Anti-glycoprotein E (gE) antibody concentrations, gE-specific CD4 T-cell frequencies, and vaccine response rates were assessed at 1M post-dose 1, and 1M and 12M post-dose 2. Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days after each dose, respectively. Solicited general symptoms and unsolicited AEs were also collected 7 days before first vaccination. Serious AEs (including biopsy-proven allograft rejections) and potential immune-mediated diseases (pIMDs) were recorded up to 12M post-dose 2. RESULTS: Two hundred sixty-four participants (RZV: 132; placebo: 132) were enrolled between March 2014 and April 2017. gE-specific humoral and cell-mediated immune responses were higher in RZV than placebo recipients across postvaccination time points and persisted above prevaccination baseline 12M post-dose 2. Local AEs were reported more frequently by RZV than placebo recipients. Overall occurrences of renal function changes, rejections, unsolicited AEs, serious AEs, and pIMDs were similar between groups. CONCLUSIONS: RZV was immunogenic in chronically immunosuppressed RT recipients. Immunogenicity persisted through 12M postvaccination. No safety concerns arose. CLINICAL TRIALS REGISTRATION: NCT02058589.


Assuntos
Vacina contra Herpes Zoster , Herpes Zoster , Imunogenicidade da Vacina , Transplante de Rim , Adulto , Anticorpos Antivirais , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Vacinas Sintéticas/efeitos adversos
12.
Int J Obes (Lond) ; 44(3): 715-726, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31467421

RESUMO

OBJECTIVES: High-esterified pectin (HEP) is a prebiotic able to modulate gut microbiota, associated with health-promoting metabolic effects in glucose and lipid metabolism and adipostatic hormone sensitivity. Possible effects regulating adaptive thermogenesis and energy waste are poorly known. Therefore, we aimed to study how physiological supplementation with HEP is able to affect microbiota, energy metabolism and adaptive thermogenic capacity, and to contribute to the healthier phenotype promoted by HEP supplementation, as previously shown. We also attempted to decipher some of the mechanisms involved in the HEP effects, including in vitro experiments. SUBJECTS AND EXPERIMENTAL DESIGN: We used a model of metabolic malprogramming consisting of the progeny of rats with mild calorie restriction during pregnancy, both under control diet and an obesogenic (high-sucrose) diet, supplemented with HEP, combined with in vitro experiments in primary cultured brown and white adipocytes treated with the postbiotic acetate. RESULTS: Our main findings suggest that chronic HEP supplementation induces markers of brown and white adipose tissue thermogenic capacity, accompanied by a decrease in energy efficiency, and prevention of weight gain under an obesogenic diet. We also show that HEP promotes an increase in beneficial bacteria in the gut and peripheral levels of acetate. Moreover, in vitro acetate can improve adipokine production, and increase thermogenic capacity and browning in brown and white adipocytes, respectively, which could be part of the protection mechanism against excess weight gain observed in vivo. CONCLUSION: HEP and acetate stand out as prebiotic/postbiotic active compounds able to modulate both brown-adipocyte metabolism and browning and protect against obesity.


Assuntos
Adipócitos Marrons/efeitos dos fármacos , Adipócitos Brancos/efeitos dos fármacos , Pectinas/farmacologia , Prebióticos , Termogênese/efeitos dos fármacos , Acetatos/metabolismo , Acetatos/farmacologia , Adipócitos Marrons/citologia , Adipócitos Marrons/metabolismo , Adipócitos Brancos/citologia , Adipócitos Brancos/metabolismo , Animais , Restrição Calórica , Suplementos Nutricionais , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino , Pectinas/administração & dosagem , Pectinas/metabolismo , Gravidez , Ratos , Ratos Wistar
13.
Soft Matter ; 16(45): 10221-10243, 2020 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-33185218

RESUMO

Particle-stabilised or Pickering emulsions are versatile systems. In the past 10 years a new application has emerged in the field of catalysis to use them as vehicles to carry out catalytic reactions, allowing a more environmentally friendly process with high conversions and selectivities and important advantages for catalyst recovery. As the area has advanced rapidly, the intention of this review is to summarize the latest innovations being reported. An overview is given regarding the kinds of liquid phases comprising the emulsion system, the different types of solid particle stabilizers (whether they contain catalyst or not) and the catalytic reactions studied. A section describing methods for recovering the catalyst is also included, in which various stimuli are discussed. Finally, the importance of using Pickering emulsions to carry out reactions in flow and in multi-step cascade systems is highlighted with various examples to support the benefits of transferring this technology to industrial processes.

14.
Curr Urol Rep ; 21(1): 4, 2020 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-31960160

RESUMO

PURPOSE OF REVIEW: This review provides a critical literature overview of the risks and benefits of transplantectomy in patients with a failed allograft. Additionally, it offers a summary of related problems, primarily alloantibody sensitization in the event of nephrectomy and immunosuppression weaning. RECENT FINDINGS: Transplant nephrectomy has high morbidity and mortality rates. The morbidity of transplant nephrectomy (4.3 to 82%) is mostly due to hemorrhage or infection. Mortality rates range from 1.2 to 39%, and most are due to sepsis. Transvascular graft embolization has been described as a less invasive alternative technique for the management of symptomatic graft rejection, with minimal complications compared with transplantectomy. The number of patients with a failed allograft returning to dialysis is increasing. The role of allograft nephrectomy in the management of asymptomatic transplant failure is still controversial and up today continues to depend on the usual clinical practice of each institution. The less invasive transvascular embolization could have applicability in asymptomatic patients with the obvious lower morbidity and mortality rate.


Assuntos
Rejeição de Enxerto/cirurgia , Transplante de Rim/efeitos adversos , Nefrectomia/métodos , Transplantes/cirurgia , Aloenxertos/cirurgia , Rejeição de Enxerto/etiologia , Humanos
15.
Langmuir ; 35(20): 6693-6707, 2019 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-31063381

RESUMO

The possibility of stabilizing emulsions with polyelectrolyte complexes (PEC) obtained from the interaction of two non-surface-active oppositely charged polyelectrolytes (PEL) is described. Poly(allylamine hydrochloride) (PAH) and poly(4-styrene sulfonate) sodium salt are selected as the weak cationic and the strong anionic polyelectrolyte, respectively. Aqueous polymer mixtures are investigated by light scattering to determine the size of the complexes and whether precipitation or complex coacervation occurs. The effects of PEL mixing ratio, pH, and PEL concentration are studied in detail. By increasing the pH, the transition precipitate-precipitate/coacervate-coacervate-polymer solution is observed. At low pH, both PEL are fully ionized and therefore precipitates (soft particles) arise as a result of strong electrostatic interactions. By increasing the pH, the degree of ionization of PAH decreases and weak electrostatic interactions ensue, supporting the formation of coacervate droplets. The most stable oil-in-water emulsions are prepared from aqueous mixtures around charge neutralization. Although emulsions can be prepared from coacervate droplet dispersions, their coalescence stability is worse than those stabilized by soft PEC particles. By increasing the PEL concentration, the average droplet diameter decreases and the fraction of cream in the emulsion increases for emulsions prepared with PEC particles, following the limited coalescence model. However, at high concentrations, emulsion stability is slightly worse probably due to extensive aggregation of the particles. Viscous high internal phase emulsions can be prepared at low pH in which oil droplets are deformed. Here, PEC particles are detected only at the oil-water interface. At lower oil content, excess particles form a network in the aqueous phase aiding emulsion stability to coalescence.

16.
Psychooncology ; 28(1): 116-121, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30312500

RESUMO

OBJECTIVE: The aim of this study was to develop and validate a patient-reported outcome measure to evaluate body image concerns in head and neck cancer (HNC) patients. METHODS: Items were created using a combination of deductive (eg, US Food and Drug Administration Qualification of Clinical Outcome Assessments, literature review) and inductive approaches (eg, subject matter experts, HNC patients). Items were translated for use in both Canadian English and Canadian French using back-translation. A two-step empirical validation process using the Classical Test Theory (CTT) and Rasch Measurement Theory (RMT) was conducted with 224 and 258 HNC patients, respectively, having undergone disfiguring surgery within the past 3 years. RESULTS: Analyses suggest two subscales for MBIS-HNC: social discomfort (10 items) and negative self-image (11 items). The McGill Body Image Concerns Scale-Head and Neck Cancer (MBIS-HNC) is reliable with high internal consistency (0.98), high test-retest reliability over a two-week period (ICC = 0.88), moderate to high convergent validity (range r = 0.43-0.81), and divergent validity (range r = 0.12-0.15). RMT was used in addition to CTT. Disordered thresholds led to the modification of the number of response options, and items were deleted based on differential item functioning and high local dependency. Unidimensionality of both subscales and supporting a total score was confirmed. The measure was however characterized by the presence of an important floor effect, confirmed with poor targeting as demonstrated by the person-item threshold distribution. CONCLUSION: Evidence gathered from our theory-driven validation study using CTT and RMT provides practitioners and researchers with a useful and easy to use self-report measure.


Assuntos
Imagem Corporal/psicologia , Neoplasias de Cabeça e Pescoço/psicologia , Autorrelato , Inquéritos e Questionários/normas , Adulto , Canadá , Feminino , Humanos , Masculino , Oncologia , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Psicometria/métodos , Reprodutibilidade dos Testes , Tradução
17.
Soft Matter ; 14(2): 239-254, 2018 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-29231947

RESUMO

We investigate the possibility of stabilising oil-water emulsions from the polyelectrolyte complexes (PEC) obtained in mixtures of a strong cationic polyelectrolyte (poly(diallyldimethylammonium chloride), PDADMAC) and a weak anionic one (poly(acrylic acid)sodium salt, PAANa). Unlike other previous work however, both polyelectrolytes (PEL) are chosen as they are completely water-soluble and possess no surface activity when present alone over nearly all the pH range. In water, the effects of PEL concentration, PEL mixing ratio and pH on the formation of PEC are studied in detail. At low pH where the anionic PEL is uncharged, complex coacervation occurs in which droplets rich in both polymers are dispersed in water. At intermediate pH, the PEC comprise a mixture of coacervate droplets and solid particles. At high pH where the anionic PEL is significantly charged, only complex coacervation is observed. On addition of dodecane followed by homogenisation, no stable emulsions arose from dispersions containing solid particle PEC due to either the large precursor particle aggregates or their inherent hydrophilicity. By contrast, oil-in-water emulsions stable to coalescence could be prepared from coacervate dispersions. We discuss the feasibility of the coacervate phase spreading at the oil-water interface in terms of the relevant spreading coefficients and compare the predictions with experiment for a range of oils. We encounter oils whose drops become engulfed by the coacervate phase as well as oils where no engulfing occurs.

18.
J Phys Chem A ; 122(40): 7941-7953, 2018 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-30265538

RESUMO

Ultrafast time-resolved electronic and infrared absorption measurements have been carried out on a series of Ru(II) polypyridyl complexes in an effort to delineate the dynamics of vibrational relaxation in this class of charge transfer chromophores. Time-dependent density functional theory calculations performed on compounds of the form [Ru(CN-Me-bpy) x(bpy)3-x]2+ ( x = 1-3 for compounds 1-3, respectively, where CN-Me-bpy is 4,4'-dicyano-5,5'-dimethyl-2,2'-bipyridine and bpy is 2,2'-bipyridine) reveal features in their charge-transfer absorption envelopes that allow for selective excitation of the Ru(II)-(CN-Me-bpy) moiety, the lowest-energy MLCT state(s) in each compound of the series. Changes in band shape and amplitude of the time-resolved differential electronic absorption data are ascribed to vibrational cooling in the CN-Me-bpy-localized 3MLCT state with a time constant of 8 ± 3 ps in all three compounds. This conclusion was corroborated by picosecond time-resolved infrared absorption measurements; sharpening of the CN stretch in the 3MLCT excited state was observed with a time constant of 3.0 ± 1.5 ps in all three members of the series. Electronic absorption data acquired at higher temporal resolution revealed spectral modulation over the first 2 ps occurring with a time constant of τ = 170 ± 50 fs, in compound 1; corresponding effects are significantly attenuated in compound 2 and virtually absent in compound 3. We assign this feature to intramolecular vibrational redistribution (IVR) within the 3MLCT state and represents a rare example of this process being identified from time-resolved electronic absorption data for this important class of chromophores.

19.
J Clin Child Adolesc Psychol ; 47(sup1): S467-S479, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29252011

RESUMO

The purpose of this article is to present the results of a treatment development study designed to examine the feasibility, acceptability, and preliminary efficacy of motivational enhancement therapy (MET) for substance using, truant adolescents plus the Family Check-Up (FCU) for parents. A randomized controlled trial was used to test the hypothesis that MET plus the FCU (MET/FCU) would lead to greater reductions in alcohol and marijuana use as well as truant behavior compared to a psychoeducation (PE) condition delivered to both adolescents and parents. Participants (n = 69; M age = 15.8 years) were 39% female, 59% White, and 31% Hispanic/Latino. Adolescents were referred from family court, from school truancy courts, from school counselors, or after presentations in high school health classes. Eligible participants reported using marijuana at least 3 times in the prior 90 days and a history of school truancy in the prior school year. The MET/FCU condition was found to be feasible to implement and was acceptable to both adolescents and parents. The PE condition was also found to be an acceptable and credible comparison condition by participants. Results at the 6-month follow-up favored MET/FCU over PE on days of marijuana use and number of times marijuana was smoked per day (medium effect), high volume drinking days and other drug use (small to medium effects), truancy indicators (small effects), parental monitoring (medium to large effects), and parent-teen problem solving (medium to large effects). A larger study to test the efficacy of the MET/FCU appears warranted based on these promising findings.


Assuntos
Comportamento do Adolescente/psicologia , Entrevista Motivacional/métodos , Pais/psicologia , Instituições Acadêmicas , Estudantes/psicologia , Transtornos Relacionados ao Uso de Substâncias/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Motivação/fisiologia , Projetos Piloto , Transtornos Relacionados ao Uso de Substâncias/diagnóstico , Transtornos Relacionados ao Uso de Substâncias/terapia
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