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1.
Appl Physiol Nutr Metab ; 47(7): 787-803, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35442812

RESUMEN

Evidence-based guidelines represent the highest level of scientific evidence to identify best practices for clinical/public health. However, the availability of guidelines do not guarantee their use, targeted knowledge translation strategies and tools are necessary to help promote uptake. Following publication of the 2019 Canadian Guideline for Physical Activity throughout Pregnancy, the Get Active Questionnaire for Pregnancy, and an associated Health Care Provider Consultation Form for Prenatal Physical Activity were developed to promote guideline adoption and use amongst pregnant individuals and health care providers. This paper describes the process of developing these tools. First, a survey was administered to qualified exercise professionals to identify the barriers and facilitators in using existing prenatal exercise screening tools. A Working Group of researchers and stakeholders then convened to develop an evidence-informed exercise pre-participation screening tool for pregnant individuals, building from previous tool and survey findings. Finally, end-user feedback was solicited through a survey and key informant interviews to ensure tools are feasible and acceptable to use in practice. The uptake and use of these documents by pregnant individuals, exercise, and health care professionals will be assessed in future studies. Novelty: Evidence supports the safety/benefits of exercise for most pregnant individuals; however, exercise is not recommended for a small number of individuals with specific medical conditions. The Get Active Questionnaire for Pregnancy and Health Care Provider Consultation Form for Physical Activity during Pregnancy identify individuals where prenatal exercise may pose a risk, while reducing barriers to physical activity participation for the majority of pregnant individuals.


Asunto(s)
Terapia por Ejercicio , Ejercicio Físico , Canadá , Femenino , Humanos , Embarazo , Encuestas y Cuestionarios
2.
Langmuir ; 37(15): 4666-4677, 2021 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-33826345

RESUMEN

In pursuit of friendlier conditions for the preparation of high-value biochemicals, we developed catalytic synthesis of γ-valerolactone by levulinic acid hydrogenation with formic acid as the hydrogen source. Both levulinic and formic acid are intermediate products in the biomass transformation processes. The objective of the work is twofold: the development of a novel approach for milder synthesis conditions to produce γ-valerolactone and the reduction of the economic cost of the catalyst. Ni-rich Ni-Pt mesoporous nanowires were synthesized in an aqueous medium using a combined hard-soft-template-assisted electrodeposition method, in which porous polycarbonate membranes controlled the shape and the Pluronic P-123 copolymer served as the porogen agent. The electrodeposition conditions selected favored nickel deposition and generated nanowires with nickel percentages above 75 atom %. The increase in deposition potential favored nickel deposition. However, it was detrimental for the porous diameter because the mesoporous structure is promoted by the presence of the platinum-rich micelles near the substrate, which is not favored at more negative potentials. The prepared catalysts promoted the complete transformation to γ-valerolactone in a yield of around 99% and proceeded with the absence of byproducts. The coupling temperature and reaction time were optimized considering the energy cost. The threshold operational temperature was established at 140 °C, at which, 120 min was sufficient for attaining the complete transformation. Working temperatures below 140 °C rendered the reaction completion difficult. The Ni78Pt22 nanowires exhibited excellent reusability, with minimal nickel leaching into the reaction mixture, whereas those with higher nickel contents showed corrosion.

3.
Nanomaterials (Basel) ; 10(8)2020 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-32717944

RESUMEN

The use of soft templates for the electrosynthesis of mesoporous materials has shown tremendous potential in energy and environmental domains. Among all the approaches that have been featured in the literature, block copolymer-templated electrodeposition had robustness and a simple method, but it practically cannot be used for the synthesis of mesoporous materials not based on Pt or Au. Nonetheless, extending and understanding the possibilities and limitations of block copolymer-templated electrodeposition to other materials and substrates is still challenging. Herein, a critical analysis of the role of the solution's primary electroactive components and the applied potential were performed in order to understand their influences on the mesostructure of Ni-rich Ni-Pt mesoporous films. Among all the components, tetrahydrofuran and a platinum (IV) complex were shown to be crucial for the formation of a truly 3D mesoporous network. The electrosynthesized well-ordered mesoporous Ni-rich Ni-Pt deposits exhibit excellent electrocatalytic performance for methanol oxidation in alkaline conditions, improved stability and durability after 1000 cycles, and minimal CO poisoning.

4.
Adv Sci (Weinh) ; 7(3): 1902447, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32042564

RESUMEN

Water remediation and development of carbon-neutral fuels are a priority for the evermore industrialized society. The answer to these challenges should be simple, sustainable, and inexpensive. Thus, biomimetic-inspired circular and holistic processes combing water remediation and biofuel production can be an appealing concept to deal with these global issues. A simple circular approach using helical Spirulina platensis microalgae as biotemplates to synthesize Ni@ZnO@ZnS photocatalysts for efficient solar water decontamination and bioethanol production during the recycling process is presented. Under solar irradiation, the Ni@ZnO@ZnS-Spirulina photocatalyst exhibits enhanced activity (mineralization efficiency >99%) with minimal photocorrosion and excellent reusability. At the end of its effective lifetime for water remediation, the microalgae skeleton (mainly glycogen and glucose) of the photocatalyst is recycled to directly produce bioethanol by simultaneous saccharification and fermentation process. An outstanding ethanol yield of 0.4 L kg-1, which is similar to the highest yield obtained from oxygenic photosynthetic microorganisms, is obtained. Thus, the entire process allows effective solar photocatalytic water remediation and bioethanol production at room temperature using simple and easily scalable procedures that simultaneously fixes carbon dioxide, thereby constituting a zero-carbon-emission circular process.

5.
Obstet Gynecol Surv ; 74(8): 481-489, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31418450

RESUMEN

IMPORTANCE: Physical activity during pregnancy can offer many maternal and fetal health benefits. OBJECTIVE: The aim was to summarize American, Canadian, and international recommendations published recently on physical activity during pregnancy to aid health care providers in their delivery of advice on the topic. EVIDENCE ACQUISITION: A descriptive review of 3 national guidelines and 1 international guideline on physical activity during pregnancy was conducted. The guidelines included the 2019 Canadian recommendations, the 2018 United States' Physical Activity Guidelines for Americans (second edition), the 2015 (reaffirmed in 2017) American College of Obstetrics and Gynecology guideline, and the 2016-2018 International Olympic Committee recommendations for recreational and elite athletes. RESULTS: For apparently healthy women, under the guidance of their health care provider, moderate-intensity physical activity using both aerobic and muscle conditioning activities is recommended. The guidelines recommended at least 150 min/wk spread throughout the week (Canada, United States) or at least 20 to 30 min/d (American College of Obstetrics and Gynecology). CONCLUSIONS AND RELEVANCE: This summary of 4 recent guidelines can facilitate use of updated recommendations by health care providers regarding physical activity during pregnancy. More detailed evidence-based guidelines on physical activity during postpartum are needed.


Asunto(s)
Terapia por Ejercicio/normas , Ejercicio Físico , Obstetricia/normas , Guías de Práctica Clínica como Asunto , Atención Prenatal/normas , Canadá , Femenino , Humanos , Embarazo , Estados Unidos
11.
Best Pract Res Clin Obstet Gynaecol ; 43: 107-114, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28190696

RESUMEN

Biomedical research is currently guided by ethical standards that have evolved over many centuries. Historical and political events, social and legal considerations, and continuous medical and technological advances have led to the prevailing research ethics and practice. Currently, patients and research subjects have complete autonomy while under medical care or when volunteering as research subjects. Enrolling volunteers in human subjects research includes a detailed and meaningful informed consent process that follows the cardinal principles of ethics: autonomy, beneficence, nonmaleficence, and justice. These principles were gradually adopted after World War II, primarily in response to the unethical behavior of German physicians and scientists during the Third Reich. This review emphasizes the importance of historical milestones and the essential role that ethics has in contemporary medical research. Research protocols should achieve maximum benefits for the society, have clinical and scientific value, be subject to independent review, respect human dignity, and follow the principles of informed consent, and most importantly, subjects should have complete autonomy. However, current principles and regulations cannot cover every conceivable situation, particularly in view of the new advances in science and technology. New and evolving medical technology, genetic research, therapeutic interventions, and innovations challenge society to maintain the highest moral and ethical principles.


Asunto(s)
Beneficencia , Investigación Biomédica/ética , Consentimiento Informado/ética , Sujetos de Investigación , Humanos , Autonomía Personal
12.
Br J Sports Med ; 50(21): 1297-1305, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27733352

RESUMEN

This is Part 2 of 5 in the series of evidence statements from the IOC expert committee on exercise and pregnancy in recreational and elite athletes. Part 1 focused on the effects of training during pregnancy and on the management of common pregnancy-related symptoms experienced by athletes. In Part 2, we focus on maternal and fetal perinatal outcomes.

14.
Clin Obstet Gynecol ; 59(3): 639-44, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27398880

RESUMEN

In recent years it has been recognized that in all phases of life, including pregnancy, physical activity promotes health benefits and precludes comorbidities, the scientific evidence is indisputable. Several organizations around the world have updated in recent years the guidelines and recommendations for exercise in pregnancy. The December 2015, updated guidelines of the American College of Obstetricians and Gynecologists emphasize that physical activity in pregnancy has minimal risk. Although recommending exercise in pregnancy, the anatomic/physiological changes, absolute and relative contraindications should be considered. Women who exercised regularly before pregnancy, in the absence of contraindications, can continue and engage in moderate to strenuous activities, although information on strenuous activities in pregnancy is still limited. This review summarizes the most recent published and recommended guidelines.


Asunto(s)
Ejercicio Físico , Guías de Práctica Clínica como Asunto , Embarazo , Femenino , Estilo de Vida Saludable , Humanos , Obesidad/prevención & control , Periodo Posparto , Complicaciones del Embarazo/prevención & control , Riesgo
15.
Clin Obstet Gynecol ; 59(3): 620-8, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27135873

RESUMEN

Exercise plays an important role in reducing the prevalence of gestational diabetes mellitus (GDM) in women with or without risk factors. GDM risk factors include obesity, family history of diabetes, high-risk ethnicity, increased maternal age, history of GDM, delivering a macrosomic infant, excessive gestational weight gain early in pregnancy (before glucose screening), sedentary behavior, low physical activity, and vitamin D deficiency. Most GDM patients can be managed with lifestyle modifications that include medical nutrition therapy and physical activity. When adherence is high and women are fully engaged in the exercise program, GDM can be effectively managed and prevented.


Asunto(s)
Diabetes Gestacional/terapia , Ejercicio Físico/fisiología , Diabetes Gestacional/prevención & control , Femenino , Humanos , Guías de Práctica Clínica como Asunto , Embarazo , Factores de Riesgo
16.
Br J Sports Med ; 50(10): 571-89, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-27127296
17.
Early Hum Dev ; 94: 33-41, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26803360

RESUMEN

Pregnancy is characterized by physiological, endocrine and metabolic adaptations creating a pseudo-diabetogenic state of progressive insulin resistance. These adaptations occur to sustain continuous fetal requirements for nutrients and oxygen. Insulin resistance develops at the level of the skeletal muscle, and maternal exercise, especially activity involving large muscle groups improve glucose tolerance and insulin sensitivity. We discuss the maternal hormonal and metabolic changes associated with a normal pregnancy, the metabolic dysregulation that may occur leading to gestational diabetes mellitus (GDM), and the consequences to mother and fetus. We will then examine the acute and chronic (training) responses to exercise in the non-pregnant state and relate these alterations to maternal exercise in a low-risk pregnancy, how exercise can be used to regulate glucose tolerance in women at risk for or diagnosed with GDM. Lastly, we present key exercise guidelines to help maintain maternal glucose regulation and suggest future research directions.


Asunto(s)
Diabetes Gestacional/metabolismo , Ejercicio Físico , Feto/metabolismo , Embarazo/metabolismo , Adaptación Fisiológica , Glucemia/metabolismo , Diabetes Gestacional/etiología , Diabetes Gestacional/prevención & control , Femenino , Hormonas/metabolismo , Humanos , Embarazo/fisiología
18.
Best Pract Res Clin Obstet Gynaecol ; 29(1): 123-32, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25240421

RESUMEN

The global obesity epidemic continues unabated, now rapidly expanding to developing countries. Multiple comorbidities and premature mortality are associated with obesity, most frequently diabetes. The associated financial and economical burden is escalating as well. The sedentary lifestyle adopted by many pregnant women because of traditional practices and the current recommendation for gestational weight gain are contributing factors to the obesity and diabetes epidemic. Physical inactivity is recognized as an independent risk factor for obesity insulin resistance and type 2 diabetes; the physiological and hormonal changes associated with pregnancy magnify this risk. Conversely, evidence and accumulated experience indicate that antenatal lifestyle interventions that include physical activity and judicious dieting could improve the pregnancy outcome and reduce the risk of gestational diabetes and is effective as an adjunctive therapy for diabetes in pregnancy. All major professional organizations, among them American Congress of Obstetricians and Gynecologists (ACOG), American Diabetes Association (ADA), Royal College of Obstetricians and Gynaecologists (RCOG), and Society of Obstetricians and Gynaecologists of Canada (SOGC), recommend lifestyle interventions that include diet and exercise to prevent or manage gestational diabetes or diabetes mellitus.


Asunto(s)
Diabetes Gestacional/prevención & control , Dietoterapia , Terapia por Ejercicio , Obesidad/terapia , Atención Prenatal/métodos , Terapia Combinada , Diabetes Gestacional/etiología , Femenino , Humanos , Resistencia a la Insulina , Estilo de Vida , Embarazo , Complicaciones del Embarazo/terapia , Resultado del Embarazo , Factores de Riesgo , Aumento de Peso
19.
Twin Res Hum Genet ; 17(2): 127-33, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24423582

RESUMEN

Limited data is available that estimates the effect of gestational weight gain on maternal and neonatal outcomes in term twin pregnancies in obese women. A historical cohort study of 831 obese (BMI ≥30.0 kg/m2) women in Missouri delivering 1,662 liveborn, term (≥37 weeks gestation) twin infants in 1998-2005 was conducted. Three gestational weight gain categories were examined: <25 pounds, 25-42 pounds, and >42 pounds. Adjusted odds ratios were calculated with multiple logistic regression, using the 2009 Institute of Medicine provisional guideline of 25-42 pounds as the reference group. Significant increasing trends with gestational weight gain were found for preeclampsia (p < .05), larger twin birth weight (p < .01), smaller twin birth weight (p < .001), and infants weighing >2,500 grams (p < .001). Significant increasing trends for preeclampsia and for cesarean delivery were found in concordant twin pairs (smaller twin >80% of birth weight of larger twin). Women who gained >42 pounds had a borderline significantly higher odds of preeclampsia than women who gained 25-42 pounds (adjusted OR 1.72; 95% CI 1.00-2.99, p = .052). No significant differences were found for 1-min Apgar score <4, 5-min Apgar score <7, or infant mortality ≤1 year. Our study suggests that increasing gestational weight gain is associated with larger infants but increased risk of preeclampsia and cesarean delivery in term twin pregnancies in obese women. Limiting gestational weight gain could reduce the risk of preeclampsia and cesarean delivery. Prospective studies of other study populations and maternal/infant outcomes are needed to evaluate the efficacy of the Institute of Medicine guideline.


Asunto(s)
Obesidad/epidemiología , Complicaciones del Embarazo/epidemiología , Resultado del Embarazo/epidemiología , Embarazo Gemelar/estadística & datos numéricos , Aumento de Peso , Adulto , Femenino , Humanos , Embarazo , Factores de Riesgo
20.
Matern Child Health J ; 18(4): 1038-47, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24077985

RESUMEN

Small-for-gestational-age (SGA) and large-for gestational-age (LGA) infants are associated with increased adverse outcomes. While studies have estimated the association of gestational weight gain with birth weight in obese women, estimates are lacking by obesity class and diabetic status. A population-based historical cohort study of 66,010 obese pregnant women in Missouri delivering liveborn, singleton, term infants in 2002­2008 was conducted. Adjusted odds ratios for SGA and LGA infants were calculated for gestational weight gain categories with multiple logistic regression using the revised Institute of Medicine(IOM) recommended 11­20 pounds as the reference group. A weight gain of 3­10 pounds was not significantly associated with an increased risk of an SGA infant compared to 11­20 pounds in 5/6 obesity class/diabetic status combinations.The exception was Class I Obese non-diabetic women(adjusted odds ratio = 1.28, 95 % confidence interval 1.07, 1.52). When lower amounts of weight gain were considered, diabetic women who gained ≤2 pounds (including women who lost weight) did not have a significantly increased risk of an SGA infant compared to diabetic women who gained 11­20 pounds in any obesity class. Weight gains less than 11­20 pounds were significantly associated with a decreased risk of an LGA infant in 5/6 obesity class/diabetic status combinations. Weight gains lower than the IOM recommendation of 11­20 pounds during pregnancy for obese women generally were significantly associated with decreased risk of LGA infants without being significantly associated with increased risk of SGA infants and differed by obesity class and diabetic status.


Asunto(s)
Peso al Nacer , Diabetes Mellitus/fisiopatología , Obesidad/complicaciones , Complicaciones del Embarazo/fisiopatología , Resultado del Embarazo , Aumento de Peso/fisiología , Adulto , Índice de Masa Corporal , Estudios de Cohortes , Intervalos de Confianza , Femenino , Macrosomía Fetal/epidemiología , Macrosomía Fetal/fisiopatología , Edad Gestacional , Humanos , Recién Nacido , Recién Nacido Pequeño para la Edad Gestacional , Masculino , Análisis Multivariante , Obesidad/diagnóstico , Oportunidad Relativa , Embarazo , Adulto Joven
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