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1.
Microvasc Res ; 144: 104418, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35931124

RESUMEN

Microcirculation analysis of the brain cortex is challenging because surface perfusion varies rapidly in small space-time regions and is bone protected. The laser speckle contrast imaging (LSCI) technique allows analyzing in vivo brain vascular perfusion generating a large amount of data that requires sophisticated data analytics, making researchers invest much effort in processing. Our research question was whether the reduced placental perfusion model (RUPP) of preeclampsia (PE) was associated with impaired blood perfusion in the offspring's brains. We aimed to develop a robust numerical approach that mainly consisted of applying a signal-processing tool for calculating optimal segmentation and piece-wise fits of the offspring's brain perfusion signals obtained from the LSCI technique. We combined this tool with the usual statistical analysis, implementing both in Matlab software. We performed brain perfusion measurements from offspring (five days postnatal, P5) of control pregnant dams (sham, n = 13) and of RUPP dams (RUPP, n = 7) using the Pericam® PSI-HR system at a basal condition and after thermal stimuli (warm and cold). We found that pups of RUPP mice exhibited significant differences in perfusion and vascular response to thermal stimuli compared to the sham mice. These differences were associated with high data variability in the Sham group, while in the RUPP group, perfusion looks "stiffer." Data also suggest sex-dimorphism in the vascular response since female pups in the Sham group but not male pups showed statistically significant differences in response to the warm stimulus. Again, this sex-related difference was absent in pups of RUPP mice. In conclusion, we present a robust quantitative approach for LSCI measurements that revealed anomalies in the brain blood flow in offspring of the RUPP model of PE.


Asunto(s)
Preeclampsia , Animales , Circulación Cerebrovascular , Femenino , Humanos , Imágenes de Contraste de Punto Láser , Ratones , Perfusión/efectos adversos , Placenta/irrigación sanguínea , Embarazo , Útero/irrigación sanguínea
2.
Math Comput Simul ; 193: 1-18, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34608351

RESUMEN

The COVID-19 disease has forced countries to make a considerable collaborative effort between scientists and governments to provide indicators to suitable follow-up the pandemic's consequences. Mathematical modeling plays a crucial role in quantifying indicators describing diverse aspects of the pandemic. Consequently, this work aims to develop a clear, efficient, and reproducible methodology for parameter optimization, whose implementation is illustrated using data from three representative regions from Chile and a suitable generalized SIR model together with a fitted positivity rate. Our results reproduce the general trend of the infected's curve, distinguishing the reported and real cases. Finally, our methodology is robust, and it allows us to forecast a second outbreak of COVID-19 and the infection fatality rate of COVID-19 qualitatively according to the reported dead cases.

3.
Pain Med ; 22(11): 2542-2549, 2021 Nov 26.
Artículo en Inglés | MEDLINE | ID: mdl-33876826

RESUMEN

OBJECTIVE: Pain catastrophizing is an important psychological predictor of pain. Recent evidence suggests the relationship between catastrophizing and pain intensity could be bidirectional, but most studies have been conducted on chronic pain patients and using criticized statistical methods. The present study aimed to examine if the relationship between pain intensity and catastrophizing was bidirectional in the context of childbirth. METHODS: A total of 504 women without chronic pain were recruited on their 32-37 gestational week. They completed measures of catastrophizing and pain intensity on the first encounter and then again at 1, 3, and 6 months postpartum. The temporal relationship between the variables was assessed using a random intercept cross-lagged panel model. RESULTS: The hypothesis of reciprocal association did not receive support, as pain intensity predicted catastrophizing during the postpartum period, but catastrophizing did not show an effect over pain intensity at any moment. CONCLUSIONS: Pain intensity predicting catastrophizing is consistent with previous literature, while the lack of effect of catastrophizing over pain intensity is an unexpected result, which may suggest that catastrophizing plays a different role in the postpartum period. These results highlight the importance of timely efforts for pain management during the postpartum period and contribute to the theoretical conceptualization of catastrophizing.


Asunto(s)
Catastrofización , Periodo Posparto , Femenino , Humanos , Dolor , Manejo del Dolor , Dimensión del Dolor
4.
Int J Psychol ; 56(3): 415-424, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33038025

RESUMEN

While expectancy-value-cost theory predicts that students' task values play an important part in academic engagement, these associations have rarely been tested in science education and are even less studied in authentic classroom situations. The present study examined to what extent momentary task-values, expectations and costs are associated with students' momentary academic engagement in science classes. Momentary academic engagement was operationalised as energy (give up), dedication (grit) and absorption (flow) components of engagement. Finnish (N = 5891 beeps, 307 students) and Chilean (N = 1931 beeps, 157 students) secondary school students participated in the study using Experience Sampling Method via smartphones. When signalled, students responded to questions via smartphones concerning their momentary task values, expectations, costs and components of engagement in the current activity. The research questions were analysed with multilevel path modelling. The results showed that, for both samples task-values, expectations and costs were related to energy, dedication and absorption components of engagement in science classes. High momentary task-values were positively associated with momentary flow and grit; high momentary expectations were positively associated with high grit and low giving up in both samples; and high momentary challenge showed as increases in feelings of giving up.


Asunto(s)
Análisis y Desempeño de Tareas , Chile , Femenino , Finlandia , Humanos , Masculino , Estudiantes
5.
Int J Psychol ; 55 Suppl 1: 48-59, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31232475

RESUMEN

The purpose of this study was to evaluate the role of prosocial behaviour against aggression in a school-based universal intervention adapted in two different (non-Western) countries, Colombia and Chile. Using a randomised pretest-post-test design (and controlling for participants' gender and parents' level of education), current results highlighted different effects of a similar programme in both sites. First, the school-based universal programme designed for promoting prosocial behaviours in the peer context obtained a positive cross-national effect on prosocial behaviour rated by three informants (i.e. self, peer and teacher reports). In Colombia, this effect was moderated by the initial level of prosociality of the participants and their level of education. Mediational two-wave model corroborated that the improvement on prosocial behaviours in both countries (moderated in the case of Colombia) predicted significantly lower level of physical aggression. Characteristics of the implementation considering different cultural and historical backgrounds were discussed.


Asunto(s)
Instituciones Académicas/normas , Conducta Social , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino
6.
J Adolesc ; 64: 81-88, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29438873

RESUMEN

The present study examined the relationship between parental support, demand, psychological control and adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues in a sample of 1342 Chilean adolescents (M = 16.38, SD = 1.24, age range 14-20). Results from multiple regression analyses separated by age indicated that demand was positively associated with adolescents' beliefs about the legitimacy of parental authority for personal and multifaceted issues and that psychological control was negatively associated with adolescents' legitimacy beliefs concerning personal issues. Furthermore, parental support moderated the relationship between parental demand and adolescents' beliefs about parental legitimacy for personal and multifaceted issues: those who display high levels of demand showed stronger beliefs about parental legitimacy at high level of support. These results support the interactive effect of parental support and demand on adolescent development.


Asunto(s)
Desarrollo del Adolescente , Relaciones Padres-Hijo , Adolescente , Chile , Femenino , Humanos , Masculino , Responsabilidad Parental/psicología , Encuestas y Cuestionarios , Adulto Joven
7.
J Adolesc ; 53: 10-15, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27596054

RESUMEN

While disagreement in autonomy expectations between parents and their adolescent children is normative, it may also compromise adolescent adjustment. This study examines the association between parents' and adolescents' agreement on autonomy expectations by cognitive social domains and adolescent adjustment. A sample of 211 Chilean dyads of adolescents (57% female, Mage = 15.29 years) and one of their parents (82% mothers, Mage = 44.36 years) reported their expectations for the age at which adolescents should decide on their own regarding different issues in their life. Indexes of parent-adolescent agreement on autonomy expectations were estimated for issues of personal and prudential domains. Greater agreement in the prudential than in the personal domain was observed. For boys and girls, higher agreement in adolescent-parent autonomy expectations in the personal domain was associated with lower substance use. A negative association between level of agreement in adolescent-parent autonomy expectations in the prudential domain and externalizing behaviors and substance use was found.


Asunto(s)
Conducta del Adolescente , Ajuste Emocional , Relaciones Padres-Hijo , Padres/psicología , Autonomía Personal , Adolescente , Adulto , Análisis de Varianza , Niño , Chile , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
8.
Theor Biol Med Model ; 12: 13, 2015 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-26133367

RESUMEN

One of the main challenges in cancer modelling is to improve the knowledge of tumor progression in areas related to tumor growth, tumor-induced angiogenesis and targeted therapies efficacy. For this purpose, incorporate the expertise from applied mathematicians, biologists and physicians is highly desirable. Despite the existence of a very wide range of models, involving many stages in cancer progression, few models have been proposed to take into account all relevant processes in tumor progression, in particular the effect of systemic treatments and angiogenesis. Composite biological experiments, both in vitro and in vivo, in addition with mathematical modelling can provide a better understanding of theses aspects. In this work we proposed that a rational experimental design associated with mathematical modelling could provide new insights into cancer progression. To accomplish this task, we reviewed mathematical models and cancer biology literature, describing in detail the basic principles of mathematical modelling. We also analyze how experimental data regarding tumor cells proliferation and angiogenesis in vitro may fit with mathematical modelling in order to reconstruct in vivo tumor evolution. Additionally, we explained the mathematical methodology in a comprehensible way in order to facilitate its future use by the scientific community.


Asunto(s)
Neoplasias/irrigación sanguínea , Neovascularización Patológica , Humanos , Modelos Biológicos
9.
J Psychopathol Clin Sci ; 133(4): 297-308, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38780541

RESUMEN

According to Lewisohn's model of depression, decreases in behavioral activation (BA) occurring after facing a vital stressor may increase the risk of depression. Transition to parenthood is a potentially stressful life event that increases the risks of postpartum depression. We aimed to (a) describe the changes in BA and depressive symptomatology between the prepartum period, 1 month, 3 months, and 6 months postpartum and (b) evaluate the bidirectionality of the relationship between intraindividual changes in BA and intraindividual changes in depressive symptoms longitudinally. Chilean pregnant women (N = 503) completed a battery of questionnaires when they were between 32 and 37 weeks of gestation and 1, 3, and 6 months after delivery. A repeated measures analysis of variance showed that BA significantly decreased from prepartum to 1 month postpartum. A random intercept cross-lagged panel model supported the bidirectional inverse relationship between intraindividual changes in BA and intraindividual changes in depressive symptoms. The effect sizes of these associations were large (ßs ranging from -.141 to -.243) according to Orth et al. (2022)'s recommendations for cross-lagged effect benchmarks. This relationship showed robustness when multigroup random intercept cross-lagged panel models were conducted to adjust for several covariates (i.e., marital status, the type of health insurance, type of delivery, primiparous vs. multiparous participants, and pregnancy or delivery complication or newborn health problem). Nonetheless, reporting a previous history of major depression moderated this relationship so that intraindividual decreases in BA more likely led to intraindividual increases in depressive symptoms in people with a history of depression than in people without such a history. We discuss implications for behavioral models of depression. (PsycInfo Database Record (c) 2024 APA, all rights reserved).


Asunto(s)
Depresión Posparto , Humanos , Femenino , Depresión Posparto/epidemiología , Depresión Posparto/psicología , Adulto , Embarazo , Chile/epidemiología , Adulto Joven , Estudios Longitudinales , Depresión/psicología , Depresión/epidemiología , Periodo Posparto/psicología , Encuestas y Cuestionarios
10.
Front Public Health ; 11: 1111641, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37064668

RESUMEN

Background: One of the main lessons of the COVID-19 pandemic is that we must prepare to face another pandemic like it. Consequently, this article aims to develop a general framework consisting of epidemiological modeling and a practical identifiability approach to assess combined vaccination and non-pharmaceutical intervention (NPI) strategies for the dynamics of any transmissible disease. Materials and methods: Epidemiological modeling of the present work relies on delay differential equations describing time variation and transitions between suitable compartments. The practical identifiability approach relies on parameter optimization, a parametric bootstrap technique, and data processing. We implemented a careful parameter optimization algorithm by searching for suitable initialization according to each processed dataset. In addition, we implemented a parametric bootstrap technique to accurately predict the ICU curve trend in the medium term and assess vaccination. Results: We show the framework's calibration capabilities for several processed COVID-19 datasets of different regions of Chile. We found a unique range of parameters that works well for every dataset and provides overall numerical stability and convergence for parameter optimization. Consequently, the framework produces outstanding results concerning quantitative tracking of COVID-19 dynamics. In addition, it allows us to accurately predict the ICU curve trend in the medium term and assess vaccination. Finally, it is reproducible since we provide open-source codes that consider parameter initialization standardized for every dataset. Conclusion: This work attempts to implement a holistic and general modeling framework for quantitative tracking of the dynamics of any transmissible disease, focusing on accurately predicting the ICU curve trend in the medium term and assessing vaccination. The scientific community could adapt it to evaluate the impact of combined vaccination and NPIs strategies for COVID-19 or any transmissible disease in any country and help visualize the potential effects of implemented plans by policymakers. In future work, we want to improve the computational cost of the parametric bootstrap technique or use another more efficient technique. The aim would be to reconstruct epidemiological curves to predict the combined NPIs and vaccination policies' impact on the ICU curve trend in real-time, providing scientific evidence to help anticipate policymakers' decisions.


Asunto(s)
COVID-19 , Enfermedades Transmisibles , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias , Chile/epidemiología , Unidades de Cuidados Intensivos
11.
HERD ; 16(3): 83-103, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-37170595

RESUMEN

OBJECTIVES: Identify waiting room design features that are most appreciated by outpatients and their companions in conventional and modern waiting rooms. Evaluate if end users evaluate the environment differently from experts and in what aspects. Provide evidence-based design guidelines that orient designers and healthcare managers. BACKGROUND: Built environments are relevant in patients' evaluation of overall healthcare service. For outpatients, waiting frequently consumes the largest amount of time; thus, waiting room interior design has great potential to enhance their experience. METHODS: This study compares perceptions of two types of waiting rooms-conventional and modern-based on the spatial user experience (SUE) model. In the first stage of the study, we compared user evaluations of conventional waiting rooms (n = 137) and modern waiting rooms (n = 426) with respect to the eight SUE model dimensions using multigroup structural equation modeling. In the second stage, an expert ergonomist and two professional interior designers assessed both types of waiting rooms. RESULTS: Results showed that modern waiting rooms were perceived to be significantly better in all SUE dimensions. We also found experts' evaluations were overall consistent with users' perceptions. Discrepancies were only found in temperature perception, signage evaluation, and spatial appreciation. CONCLUSIONS: Participants valued modern style waiting room features such as good quality signage, use of armchairs and sofas, a controlled environment, and decoration. We suggest involving end users in the design process to respond to their needs and promote a positive experience. Finally, we provide easy-to-adopt design guidelines to improve patients' waiting room experience.


Asunto(s)
Pacientes Ambulatorios , Salas de Espera , Humanos , Diseño Interior y Mobiliario , Ambiente de Instituciones de Salud , Instituciones de Salud
12.
J Adolesc ; 35(3): 659-69, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21951646

RESUMEN

The study analyzes the way in which adolescents' temperamental characteristics interact with parental control to shape adolescent decision making development. A sample of high-school Chilean adolescents (N = 391) answered a self-report questionnaire that included measures of behavioral autonomy (the extent to which adolescents make decisions in personal and prudential domains), parental behavioral and psychological control, and temperamental characteristics. A path analysis model indicated that adolescents' anger-frustration had a direct association with decision-making in the personal and prudential domains; fearfulness had an inverse association with adolescent decision-making, but only in the prudential domain. Perceived psychological control was associated with adolescents' reduced decision-making autonomy in the personal domain, while perceived behavioral control was associated with less adolescent autonomy in both personal and prudential domains. Additionally, a moderation effect was found such that the association of parental behavioral control on decision-making in the prudential domain was dependent on the adolescent fearfulness level.


Asunto(s)
Toma de Decisiones , Relaciones Padres-Hijo , Psicología del Adolescente , Temperamento , Adolescente , Chile , Femenino , Humanos , Masculino , Encuestas y Cuestionarios
13.
J Homosex ; 69(10): 1777-1799, 2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34080955

RESUMEN

The Minority Stress Model has proposed that connectedness to a specific minority community may be a protective factor for stigmatized groups. This study evaluated the mediational role of connectedness with the gay men's and lesbian women's community on the relationship between two minority stressors (internalized homophobia and perceived sexual stigma) with anxiety-depressive symptomatology and life satisfaction. The sample consisted of 467 Chilean self-identified as gay men (57%) and lesbian women (43%). Results revealed that the two minority stressors were associated with anxiety-depressive symptomatology, but only internalized homophobia was associated with life satisfaction. The mediation hypothesis was partially supported by the relationship between internalized homophobia and life satisfaction. Unexpectedly, we found a negative association between connectedness with the gay men's and lesbian women's community and life satisfaction. This finding introduces a view that contrasts with the literature, which proposes that connectedness with the specific community would be a protective factor against sexual stigma.


Asunto(s)
Homofobia , Minorías Sexuales y de Género , Chile , Femenino , Homofobia/psicología , Homosexualidad Masculina/psicología , Humanos , Masculino , Salud Mental , Satisfacción Personal
14.
New Dir Child Adolesc Dev ; 2011(134): 95-109, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22147603

RESUMEN

The authors use examples of youth civic engagement from Chile, South Africa, Central/Eastern Europe, and the United States--and also emphasize diversities among youth from different subgroups within countries--to illustrate common elements of the civic domain of youth development. These include the primacy of collective activity for forming political identities and ideas and the greater heterogeneity of civic compared to other discretionary activities, the groupways or accumulated opportunities for acting due to the groups (social class, gender, ethnic, caste, etc.) to which a young person belongs, and the role of mediating institutions (schools, community-based organizations, etc.) as spaces where youths' actions contribute to political stability and change.


Asunto(s)
Desarrollo Infantil , Relaciones Comunidad-Institución , Conducta Cooperativa , Diversidad Cultural , Democracia , Cambio Social , Niño , Chile/etnología , Europa (Continente)/etnología , Humanos , Modelos Organizacionales , Grupo Paritario , Sudáfrica/etnología , Estados Unidos/etnología
15.
Front Psychol ; 12: 588017, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33897519

RESUMEN

Previous research has focused on the relation between social class and prosocial behavior. However, this relation is yet unclear. In this work, we shed light on this issue by considering the effect of the level of empathy and the social class of the recipient of help on two types of prosociality, namely helping and caring. In one experimental study, we found that for high-class participants, empathy had a positive effect on helping, regardless of the recipient's social class. However, empathy had no effect for low-class participants. When it comes to caring, empathy had a positive effect for both high and low-class participants, but only when the recipient of help belonged to the same social class. This highlights that empathy by itself is not sufficient to promote cooperative relations and that the social class of the recipient of help should be taken into account to shed light on this issue.

16.
J Adolesc ; 33(2): 285-96, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19926123

RESUMEN

Latent Class Analysis (LCA) was used to examine the patterning of adolescents' strategy choice when discussing issues with parents in a sample of 1678 Chilean 11-19 year olds (mean age=14.9). Adolescents reported whether they fully disclosed, partially disclosed, avoided the issue, or lied for six core areas that bridged personal autonomy and safety concerns. Five patterns were identified: two in which adolescents were likely to either share information about all issues or lie about them and three in which adolescents used a combination of strategies that included sharing some information while concealing other. Membership in the full disclosure class was highest among middle class youth and those who reported the highest obedience, legitimacy beliefs, parental agreement, maternal warmth and knowledge, and the fewest problem behaviors. Interestingly, adolescents in the Lie class reported both the highest level of parental monitoring and low maternal knowledge.


Asunto(s)
Conducta del Adolescente/psicología , Decepción , Relaciones Padres-Hijo , Autorrevelación , Revelación de la Verdad , Adolescente , Niño , Chile , Análisis por Conglomerados , Toma de Decisiones , Humanos , Estudios Longitudinales , Autonomía Personal , Factores Socioeconómicos , Encuestas y Cuestionarios , Adulto Joven
17.
J Psychosom Res ; 139: 110280, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33130484

RESUMEN

OBJECTIVE: To test the bidirectional relationships between physical health symptoms (PHS) and depressive symptoms (DS) as well as between the intensity of 'any pain' and DS in the pre- and postpartum period METHOD: Women (N = 615) completed the Edinburgh Postnatal Depression Scale, the Patients Health Questionnaire-15, and numerical pain rating scales when they were between 32 and 37 weeks of gestation, and subsequently one, three, and six months postpartum. We conducted two random intercept cross-lagged panel models (RI-CLPM) RESULTS: Both models presented excellent fits. The relationship between PHS and DS was bidirectional across all the data waves (χ2(9) = 6.610, p = .678, CFI = 1, TLI = 1, RMSEA = 0). The magnitude of the standardized cross-lagged regression coefficient was relatively similar from DS to PHS (raging between 0.081 and 0.171); and from PHS to DS (raging between 0.121 and 0.138). The relationship between 'any pain' intensity and DS was also bidirectional, but only during the postnatal period (χ2(9) =11.765, p = .227, CFI = 0.99, TLI = 0.98, RMSEA = 0.022). The magnitude of the standardized cross-lagged regression coefficient was higher from DS to 'any pain' intensity (raging between 0.214 and 0.216); than from 'any pain' intensity to DS (raging between 0.092 and 0.097). CONCLUSIONS: Concurrently intervening over physical and mental health symptoms could promote women's perinatal health.


Asunto(s)
Depresión Posparto/psicología , Depresión/psicología , Adolescente , Adulto , Femenino , Humanos , Estudios Longitudinales , Embarazo , Estudios Prospectivos , Adulto Joven
18.
Child Dev ; 80(2): 418-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19467001

RESUMEN

Changes in the patterning of adolescents' beliefs about the legitimate domains of parental authority were modeled in 2,611 Chilean adolescents, 11-16 years old. Transitions in adolescents' belief patterns were studied over 3 years. Latent transition analysis (LTA) revealed 3 distinct patterns of beliefs-parent control, shared control, and personal control-that differed in the extent to which adolescents believed that parents had legitimate authority over personal, prudential, and multidomain issues. Younger adolescents with fewer problem behaviors, higher self-efficacy, and more parental rules were more likely to espouse the parent control belief pattern. Adolescents' patterning of beliefs was relatively stable over time. Older adolescents with more problem behaviors and fewer parental rules were most likely to move away from the parental control status.


Asunto(s)
Conducta del Adolescente/psicología , Autoritarismo , Conflicto Familiar/psicología , Control Interno-Externo , Padres/psicología , Poder Psicológico , Adolescente , Factores de Edad , Niño , Chile , Femenino , Humanos , Masculino , Relaciones Padres-Hijo , Autoimagen , Conducta Social , Identificación Social , Percepción Social , Encuestas y Cuestionarios
19.
J Youth Adolesc ; 38(4): 500-18, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19636724

RESUMEN

The role of prejudice and ethnic awareness in the civic commitments and beliefs about the American social contract of 1,096 (53% female) adolescents (11-18 year olds, Mean = 15) from African-, Arab-, Latino-, and European-American backgrounds were compared. Ethnic awareness was higher among minority youth and discrimination more often reported by African- and Arab-Americans. Parental admonitions against discrimination were heard by all but African Americans, Latinos and those who reported prejudice heard that it could pose a barrier. Adolescents' beliefs that America is an equal opportunity society were negatively associated with experiences of discrimination and African-Americans were least likely to believe that the government was responsive to the average person. With respect to civic goals, all youth endorsed patriotism but ethnic minorities and ethnically aware youth were more committed to advocating for their ethnic group and European-Americans were less committed than were African Americans to improving race relations.


Asunto(s)
Actitud/etnología , Concienciación , Etnicidad/psicología , Etnicidad/estadística & datos numéricos , Prejuicio , Autoimagen , Percepción Social , Adolescente , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Árabes/psicología , Árabes/estadística & datos numéricos , Demografía , Femenino , Hispánicos o Latinos/psicología , Hispánicos o Latinos/estadística & datos numéricos , Humanos , Masculino , Política , Prevalencia , Identificación Social , Encuestas y Cuestionarios , Estados Unidos/epidemiología , Población Blanca/psicología , Población Blanca/estadística & datos numéricos
20.
PLoS One ; 14(5): e0217332, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31145737

RESUMEN

In this work we develop a general mathematical model and devise a practical identifiability approach for gastrointestinal stromal tumor (GIST) metastasis to the liver, with the aim of quantitatively describing therapy failure due to drug resistance. To this end, we have modeled metastatic growth and therapy failure produced by resistance to two standard treatments based on tyrosine kinase inhibitors (Imatinib and Sunitinib) that have been observed clinically in patients with GIST metastasis to the liver. The parameter identification problem is difficult to solve, since there are no general results on this issue for models based on ordinary differential equations (ODE) like the ones studied here. We propose a general modeling framework based on ODE for GIST metastatic growth and therapy failure due to drug resistance and analyzed five different model variants, using medical image observations (CT scans) from patients that exhibit drug resistance. The associated parameter estimation problem was solved using the Nelder-Mead simplex algorithm, by adding a regularization term to the objective function to address model instability, and assessing the agreement of either an absolute or proportional error in the objective function. We compared the goodness of fit to data for the proposed model variants, as well as evaluated both error forms in order to improve parameter estimation results. From the model variants analyzed, we identified the one that provides the best fit to all the available patient data sets, as well as the best assumption in computing the objective function (absolute or proportional error). This is the first work that reports mathematical models capable of capturing and quantitatively describing therapy failure due to drug resistance based on clinical images in a patient-specific manner.


Asunto(s)
Resistencia a Antineoplásicos , Neoplasias Gastrointestinales/tratamiento farmacológico , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Modelos Biológicos , Algoritmos , Neoplasias Gastrointestinales/patología , Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/secundario , Humanos , Neoplasias Hepáticas/diagnóstico por imagen , Neoplasias Hepáticas/secundario , Conceptos Matemáticos , Tomografía Computarizada por Rayos X , Insuficiencia del Tratamiento , Carga Tumoral/efectos de los fármacos
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