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1.
Artigo em Inglês | MEDLINE | ID: mdl-38692472

RESUMO

Stress exposure can lead to post-traumatic stress disorder (PTSD) in male and female rats. Social-Single Prolonged Stress (SPS) protocol has been considered a potential PTSD model. This study aimed to pharmacologically validate the Social-SPS as a PTSD model in male and female rats. Male and female Wistar rats (60-day-old) were exposed to Social-SPS protocol and treated with fluoxetine (10 mg/Kg) or saline solution intraperitoneally 24 h before euthanasia. Two cohorts of animals were used; for cohort 1, male and female rats were still undisturbed until day 7 post-Social-SPS exposure, underwent locomotor and conditioned fear behaviors, and were euthanized on day 9. Animals of cohort 2 were subjected to the same protocol but were re-exposed to contextual fear behavior on day 14. Results showed that fluoxetine-treated rats gained less body weight than control and Social-SPS in both sexes. Social-SPS effectively increased the freezing time in male and female rats on day eight but not on day fourteen. Fluoxetine blocked the increase of freezing in male and female rats on day 8. Different mechanisms for fear behavior were observed in males, such as Social-SPS increased levels of glucocorticoid receptors and Beclin-1 in the amygdala. Social-SPS was shown to increase the levels of NMDA2A, GluR-1, PSD-95, and CAMKII in the amygdala of female rats. No alterations were observed in the amygdala of rats on day fourteen. The study revealed that Social-SPS is a potential PTSD protocol applicable to both male and female rats.


Assuntos
Tonsila do Cerebelo , Medo , Fluoxetina , Ratos Wistar , Estresse Psicológico , Animais , Masculino , Feminino , Medo/efeitos dos fármacos , Medo/fisiologia , Fluoxetina/farmacologia , Tonsila do Cerebelo/efeitos dos fármacos , Tonsila do Cerebelo/metabolismo , Estresse Psicológico/metabolismo , Ratos , Modelos Animais de Doenças , Transtornos de Estresse Pós-Traumáticos/metabolismo , Transtornos de Estresse Pós-Traumáticos/psicologia , Condicionamento Clássico/efeitos dos fármacos , Condicionamento Clássico/fisiologia , Condicionamento Psicológico/efeitos dos fármacos , Condicionamento Psicológico/fisiologia , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Proteína 4 Homóloga a Disks-Large , Receptores de AMPA
2.
ACS Sustain Chem Eng ; 12(12): 4900-4911, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38550969

RESUMO

Characterizing nanomaterials is challenging due to their macromolecular nature, requiring suites of physicochemical analysis to fully resolve their structure. As such, their synthesis and scale-up are notoriously complex, especially when compared to small molecules or bulk crystalline materials, which can be provided a unique fingerprint from nuclear magnetic resonance (NMR) or X-ray diffraction (XRD) alone. In this study, we address this challenge by adopting a three-step quality-by-design (QbD) approach to the scale-up of bioinspired silica nanomaterials, demonstrating its utility toward synthesis scale-up and intensification for this class of materials in general. First, we identified material-specific surface area, pore-size distribution, and reaction yield as critical quality attributes (CQAs) that could be precisely measured and controlled by changing reaction conditions. We then identified the critical process parameters (CPPs) controlling bioinspired synthesis properties, exploring different process routes, incorporating commercial reagents, and optimizing reagent ratios, comparing silica properties against original CQA values to identify acceptable limits to each CPP. Finally, we intensified the synthesis by increasing reagent concentration while simultaneously incorporating the optimized CPPs, thereby modifying the bioinspired silica synthesis to make it compatible with existing manufacturing methods. We increased the specific yield from ca. 1.1 to 38 g/L and reduced the additive intensity from ca. 1 to 0.04 g/g product, greatly reducing both synthesis cost and waste production. These results identify a need for mapping the effects of critical process parameters on material formation pathways and CQAs to enable accelerated scale-up and transition from the lab to the market.

3.
ACS Sustain Chem Eng ; 10(16): 5288-5298, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35493693

RESUMO

To answer questions surrounding the sustainability of silica production, MilliporeSigma's DOZN 2.0 Green Chemistry Evaluator was employed as it provides quantitative values based on the 12 principles of Green Chemistry. As a first study using DOZN 2.0 to evaluate the greenness of nanomaterials, a range of silica types were considered and their greenness scores compared. These included low- and high-value silicas, both commercial and emerging, such as precipitated, gel, fumed, colloidal, mesoporous, and bioinspired silicas. When surveying these different types of silicas, it became clear that while low value silicas have excellent greenness scores, high-value silicas perform poorly on this scale. This highlighted the tension between high-value silicas that are desired for emerging markets and the sustainability of their synthesis. The calculations were able to quantify the issues pertaining to the energy-intensive reactions and subsequent removal of soft templates for the sol-gel processes. The importance of avoiding problematic solvents during processes and particularly releasing them as waste was identified. The calculations were also able to compare the amount of waste generated as well as their hazardous nature. The effects of synthesis conditions on greenness scores were also investigated in order to better understand the relationship between the production process and their sustainability.

4.
Langmuir ; 36(11): 2954-2965, 2020 03 24.
Artigo em Inglês | MEDLINE | ID: mdl-32090572

RESUMO

Phase-change perfluorocarbon microdroplets were introduced over 2 decades ago to occlude downstream vessels in vivo. Interest in perfluorocarbon nanodroplets has recently increased to enable extravascular targeting, to rescue the weak ultrasound signal of perfluorocarbon droplets by converting them to microbubbles and to improve ultrasound-based therapy. Despite great scientific interest and advances, applications of phase-change perfluorocarbon agents have not reached clinical testing because of efficacy and safety concerns, some of which remain unexplained. Here, we report that the coexistence of perfluorocarbon droplets and microbubbles in blood, which is inevitable when droplets spontaneously or intentionally vaporize to form microbubbles, is a major contributor to the observed side effects. We develop the theory to explain why the coexistence of droplets and microbubbles results in microbubble inflation induced by perfluorocarbon transfer from droplets to adjacent microbubbles. We also present the experimental data showing up to 6 orders of magnitude microbubble volume expansion, which occludes a 200 µm tubing in the presence of perfluorocarbon nanodroplets. More importantly, we demonstrate that the rate of microbubble inflation and ultimate size can be controlled by manipulating formulation parameters to tailor the agent's design for the potential theranostic application while minimizing the risk to benefit ratio.


Assuntos
Meios de Contraste/química , Fluorocarbonos/química , Microbolhas , Nanopartículas/química , Animais , Feminino , Camundongos Nus , Peso Molecular , Tamanho da Partícula , Ultrassonografia/métodos , Volatilização
5.
Int J Cardiovasc Imaging ; 35(10): 1853-1860, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31129743

RESUMO

Right ventricular longitudinal strain (RVLS) by 2D speckle-tracking echocardiography (2D-STE) is a useful parameter for assessing systolic function. However, the exact method to perform it is not well defined as some authors evaluate only free wall (FW) segments while others include all six RV segments. To compare the assessment of RVLS at rest and during exercise by these two approaches. Echocardiography was performed on 80 healthy subjects at rest and during exercise. The analysis consisted of standard and 2D-STE assessment of RV global and segmental strain tracing only RVFW and also tracing all six RV segments. At rest, RVLS could be assessed in 78 (feasibility 97.5%) subjects by both methods. However, during exercise, RVLS by RVFW method was feasible in 67 (83.8%) as compared to 74 (92.5%) by RV6S approach. Both at rest and during exercise, RVLS values by the two methods showed excellent correlation (r = > 0.90). However, RVLS values assessed by RV6S were lower (absolute values) than those by RVFW approach (RV6S vs. RVFW; rest: - 27.0 ± 3.9 vs. - 9.5 ± 3.9, p < 0.001 and exercise: - 30.7 ± 5.2 vs. - 33.3 ± 5.1, p < 0.001). Furthermore, basal strain was higher and apical strain lower (absolute values) by RV6S approach. At rest, reproducibility for RVLS was excellent and similar for the two methods. However, during exercise, reproducibility for RVFW method was poorer, especially at the apex. The two currently described methods for RVLS assessment by 2D-STE demonstrated excellent agreement. However, the RV6S approach seemed to be more feasible and reproducible, particularly during exercise. Moreover, global and segmental strain values are different with both methods and should not be interchanged.


Assuntos
Ecocardiografia Doppler , Ecocardiografia sob Estresse/métodos , Teste de Esforço , Função Ventricular Direita , Septo Interventricular/diagnóstico por imagem , Adulto , Fenômenos Biomecânicos , Estudos de Viabilidade , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Reprodutibilidade dos Testes , Sístole , Septo Interventricular/fisiopatologia , Adulto Jovem
6.
Eur J Appl Physiol ; 117(3): 389-396, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28150069

RESUMO

BACKGROUND: Characteristic right ventricle (RV) remodelling is related to endurance exercise in male athletes (MAs), but data in female athletes (FAs) are scarce. Our aim was to evaluate sex-related influence on exercise-induced RV remodelling and on RV performance during exercise. METHODS: Forty endurance athletes (>10 training hours/week, 50% female) and 40 age-matched controls (<3 h moderate exercise/week, 50% female) were included. Echocardiography was performed at rest and at maximum cycle-ergometer effort. Both ventricles were analysed by standard and speckle-tracking echocardiography. RESULTS: Endurance training induced similar structural and functional cardiac remodelling in MAs and FAs, characterized by bi-ventricular dilatation [~34%, left ventricle (LV); 29%, RV] and normal bi-ventricular function. However, males had larger RV size (p < 0.01), compared to females: RV end-diastolic area (cm2/m2): 15.6 ± 2.2 vs 11.6 ± 1.7 in athletes; 12.2 ± 2.7 vs 8.6 ± 1.6 in controls, respectively, and lower bi-ventricular deformation (RV global longitudinal strain (GLS) (%): -24.0 ± 3.6 vs -29.2 ± 3.1 in athletes; -24.9 ± 2.5 vs -30.0 ± 1.9 in controls, and LVGLS: -17.5 ± 1.4 vs -21.9 ± 1.9 in athletes; -18.7 ± 1.2 vs -22.5 ± 1.5 in controls, respectively, p < 0.01). During exercise, the increase in LV function was positively correlated (p < 0.01) with increased cardiac output (∆%LV ejection fraction, r = +0.46 and ∆%LVGLS, r = +0.36). Improvement in RV performance was blunted at high workloads, especially in MAs. CONCLUSION: Long-term endurance training induced similar bi-ventricular remodelling in MAs and FAs. Independently of training load, males had larger RV size and lower bi-ventricular deformation. Improvement in RV performance during exercise was blunted at high workloads, especially in MAs. The potential mechanisms underlying these findings warrant further investigation.


Assuntos
Adaptação Fisiológica , Exercício Físico , Função Ventricular Direita , Adulto , Estudos de Casos e Controles , Ecocardiografia , Teste de Esforço , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais
7.
Rev. chil. cardiol ; 31(3): 176-183, 2012. ilus
Artigo em Espanhol | LILACS | ID: lil-670188

RESUMO

Background: Highly trained athletes are at increased risk of atrial fibrillation (AF) and flutter. Atrial dilatation and dysfunction might be the underlying substrate for the increased risk. The aim of the present study was to relate atrial size and deformation in a selected group of highly trained athletes and patients with paroxysmal atrial fibrillation (PAF). Methods: 20 professional male hand-ball players, 18 patients with PAF and 20 healthy age-matched, non-sportive males were compared. All subjects underwent a transthoracic echocardiogram with evaluation of left atrial (LA) dimensions. Left atrial strain (LASa) and strain rate (LASRa) derived from speckle tracking were used to evaluate LA deformation post atrial contraction. Results: LA volumes were significantly larger in athletes and PAF patients compared to controls (36 + 1.7 ml/m2; 36 ± 2.3 ml/m2 and 24 + 1 ml/m2, respectively, p < 0.01;). LASa and LASRa during active atrial contraction were decreased in PAF patients compared to athletes and controls (-10.6 ± 0.2 %; -12.2 ± 0.4 % and -14.5 ± 0.5 %, p < 0.01 for LASa and -1.2 ± 0.08 sec-1; -1.5 ± 0.12 sec-1; -1.7 ± 0.13 sec-1, p= 0.04 for LASRa respectively). Athletes with LA volume > 40 ml/m2 (n=7) showed reduced LASa compared to athletes with LA volume < 40 mL/m2 (-10.3 ± 0.4% versus -13.0 ± 0.5%, p < 0.01). PAF patients had LASa values similar to those of subjects with normal LA volume. Conclusion: Athletes with increased LA volume exhibit lower strain parameters compared to subjects with PAF. It is postulated that measurement of LA strain may be used to predict development of AF in highly trained athletes.


Introducción: Atletas de alto rendimiento tienen un riesgo aumentado de desarrollar fibrilacion auricular (FA) y flutter. La dilatación y disfunción auricular podrían ser el sustrato subyacente para este incremento en el riesgo. El objetivo fue analizar y relacionar el tamaño y deformación auricular en un grupo seleccionado de atletas y en pacientes con FA paroxística. Métodos: Se incluyeron 20 jugadores de balón-mano profesionales y 20 controles sedentarios, pareados por edad y sexo, junto a 18 pacientes con FA paroxística. En todos los sujetos se realizó un estudio ecocardiográfico bidimensional con evaluación de las dimensiones y de la deformación (post contracción auricular) por strain (Sa) y strain rate (SRa) de la aurícula izquierda (AI). Resultados: El volumen AI fue significativamente mayor en atletas y pacientes con FA respecto de los controles (36 + 1,7 ml/m2; 36 ± 2,3 ml/m2 y 24 + 1 ml/m2, p < 0,01; respectivamente). El SaAI y SRaAI durante la contracción auricular estaban disminuidos en los pacientes con FA paroxística respecto de atletas y controles (-10,6 ± 0,2 %; -12,2 ± 0,4 % y -14,5 ± 0,5 %, p < 0,01 para SaAI y -1,2 ± 0,08 sec-1; -1,5 ± 0,12 sec-1; -1,7 ± 0,13 sec-1, p= 0,04 para SRaAI, respectivamente). Los atletas con un volumen AI > 40 ml/m2 (n=7) mostraron valores reducidos de SaAI comparados con atletas con un volumen AI < 40 mL/m2 (-10,3 ± 0,4% versus -13,0 ± 0,5%, p < 0,01) y éstos fueron similares a los pacientes con FA (-10,3 ± 0,4% versus -10,6 ± 0,2%, p= 0,6). Conclusiones: Una proporción de atletas con dilatación AI presentan evidencia de disfunción contráctil de la AI, caracterizado por valores de strain disminuidos que son similares a los de pacientes con FA paroxística. Esto podría corresponder a un sustrato para el desarrollo posterior de arritmias auriculares en estos atletas.


Assuntos
Humanos , Adulto , Pessoa de Meia-Idade , Atletas , Fibrilação Atrial , Átrios do Coração/patologia
9.
Health Policy Plan ; 22(4): 234-45, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17475627

RESUMO

This article reviews 44 operations research projects aiming to improve reproductive health services in Guatemala, conducted by the Population Council from 1988 to 2001. It documents the experience of the research programme, traces the extent to which research results are identifiable in existing programmes, and analyses factors influencing utilization. Utilization of research results occurs as a gradual process of information sharing, where researchers influence decision-makers through a continual stream of information rather than a single set of findings. Utilization depends on leadership, collaborative planning and implementation, close monitoring, and feasible research designs, among other factors. To influence policy formulation, organizations should form enduring links among institutions and develop critical research skills among personnel who collaborate with or manage service programmes. To understand how operations research affects policy and programme change, one must consider not just individual projects, but rather the synergistic impact of multiple projects on a broad range of themes over time.


Assuntos
Medicina Baseada em Evidências , Medicina Reprodutiva , Pesquisa , Comportamento de Escolha , Comportamento Contraceptivo , Serviços de Planejamento Familiar , Feminino , Guatemala , Humanos , Organizações
10.
Stud Fam Plann ; 36(2): 117-26, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15991649

RESUMO

The balanced counseling strategy developed in Peru improved family planning care and clients' knowledge of their contraceptive method choice, but few providers adopted it. To expand its use, an algorithm was introduced and training, job aids, and reinforcement were supplied to Ministry of Health providers, most of whom were paraprofessionals, from two areas (40 clinics) in Guatemala. Mystery clients made pretest and post-test visits to these clinics and to providers from a nonequivalent control group (40 clinics). The results showed that the strategy was used in 85 percent of the controlled consultations at the experimental clinics. Use of the strategy improved quality of care regardless of the provider's performance at baseline and regardless of ethnic or regional differences. Counseling session length increased by nine minutes, but real-client load did not change. Guatemalan clients can be expected to benefit from the strategy. The increased session length has not yet caused problems, but it may pose policy dilemmas in the future.


Assuntos
Instituições de Assistência Ambulatorial/organização & administração , Aconselhamento/normas , Fidelidade a Diretrizes , Comportamento Contraceptivo , Aconselhamento/métodos , Feminino , Guatemala , Humanos , Capacitação em Serviço , Masculino , Avaliação de Programas e Projetos de Saúde , Qualidade da Assistência à Saúde
11.
J Fam Plann Reprod Health Care ; 31(2): 128-31, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15921553

RESUMO

OBJECTIVE: To develop and test a distance-learning programme to improve the quality and efficiency of family planning services in Guatemala. METHODS: The setting was rural family planning services in Guatemala. The study design was quasi-experimental with one intervention and one control group and with pre- and post-intervention measures. Two staff members from each of 20 randomly selected health districts were trained as leaders of the training programme. In turn, the 40 trainers trained a total of 240 service providers, under the supervision of four health area facilitators. The results were compared with 20 randomly selected control health districts. The intervention was a distance-learning programme including 40 in-class hours followed by 120 inservice practice hours spread over a 4-month period. Distinctively, the programme used a cascade approach to training, intensive supervision, and close monitoring and evaluation. Patient flow analysis was used to determine number of contacts, waiting times, and the interaction time between service providers and clients. Consultation observations were used to assess the quality and completeness of reproductive health information and services received by clients. RESULTS: The intervention showed a positive impact on reducing the number of contacts before the consultation and client waiting times. More complete services and better quality services were provided at intervention clinics. Some, but not all, of the study objectives were attained. The long-term impact of the intervention is as yet unknown. CONCLUSION: Distance-learning programmes are an effective methodology for training health professionals in rural areas.


Assuntos
Educação a Distância/organização & administração , Serviços de Planejamento Familiar/organização & administração , Acessibilidade aos Serviços de Saúde/organização & administração , Relações Públicas , Agentes Comunitários de Saúde , Guatemala , Humanos , Pobreza , Avaliação de Programas e Projetos de Saúde , População Rural
12.
BMC Int Health Hum Rights ; 4(1): 2, 2004 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-15132752

RESUMO

BACKGROUND: Public sector health care providers in rural Guatemala have infrequently offered family planning information and services in routine visits. This operations research project tested a strategy to modify certain practices that prevent health workers from proactively screening clients' needs and meeting them. METHODS: The research design was quasi-experimental with a pretest-posttest-follow-up comparison group design. Health districts, which comprise health centers and posts, were purposively assigned to intervention or comparison groups to assure comparability of the two groups. The strategy was based on a job-aid designed to guide health workers in screening clients' reproductive intentions and family planning needs, help them to offer contraceptive methods if the woman expressed interest, and facilitate the provision of the method chosen at the time of the visit. The strategy was implemented at intervention sites during a period of six months. Upon completion of post-intervention measurements, the strategy was scaled up to the comparison sites, and a follow-up assessment was conducted nine months later. Results were evaluated by conducting three rounds of exit interviews with women exposed to the risk of unwanted pregnancy. RESULTS: Study results showed a two to five-fold increase in providers' screening of clients' reproductive intentions. The proportion of clients who received information about contraceptives increased from 8% at the baseline to 42% immediately post-intervention, and 36% at the follow-up survey. The intervention also proved successful in improving the role service providers play in offering women a chance to ask questions and assisting women in making a selection. The proportion of women who received a method, referral or appointment increased and remained high in the intervention group, although no change was seen in the comparison group after their participation in the strategy. CONCLUSION: The easy-to-use job aid developed for this project proved useful for screening clients' needs and reducing providers' reluctance to discuss family planning with clients and offer contraceptive services. Such family planning screening devices can be useful in traditional settings where both providers and clients shy away from discussing family planning issues.

14.
Nueva York; Population Council; 1997. 47 p. Folhetograf.
Monografia | Ministério da Saúde | ID: mis-22827
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