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Explanatory models (EMs) are used in medical anthropology to characterize individual understandings of illness. This study investigated how interdisciplinary clinical interactions elicited caregiver EMs at a pediatric cancer center in Guatemala. This qualitative study included caregivers of 20 children with newly diagnosed cancer at Unidad Nacional de Oncología Pediátrica (UNOP) in Guatemala City, Guatemala. UNOP's diagnostic process includes social work intake, psychoeducation with a psychologist, and a diagnostic conversation with an oncologist and psychologist. Audio-recordings from the diagnostic process and a semi-structured interview were obtained, transcribed, and translated from Spanish. Transcripts were coded using a priori codes based on the five explanatory model (EM) components (occurrence, causation, pathophysiology, course of sickness, and treatment), as well as disease, and illness accounts. Thematic content analysis explored the EM framework as applied to diagnostic interactions between families and clinicians. All five components of the EM were addressed during the diagnostic process at UNOP. Clinicians, particularly psychologists, initiated conversation about the EM more than caregivers. When prompted, caregivers discussed all aspects of the EM but only rarely mentioned pathophysiology. Disease accounts were primarily described by clinicians, while caregivers used illness accounts to describe cancer causation. Clinicians validated existence of both disease and illness accounts. UNOP's interdisciplinary team elicited families' beliefs and facilitated in-depth discussion of all aspects of the EM, leading to a shared understanding of cancer and its treatment. Utilizing the EM framework in clinical practice may support culturally-competent pediatric cancer care.
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BACKGROUND: Effective communication is founded on bidirectional participation from families and healthcare providers. In adult medicine, bidirectional communication promotes treatment adherence and builds the family-provider relationship. However, the relationship between communication styles in pediatrics remains poorly understood, particularly in culturally diverse settings. This study aims to investigate parent-provider communication dynamics and parental involvement during diagnostic cancer communication in Guatemala. PROCEDURE: This qualitative study included 20 families of children with cancer and 10 providers at Unidad Nacional de Oncología Pediátrica in Guatemala. Psychoeducation and diagnostic conversations between parents, psychologists, and oncologists were recorded and thematically analyzed using a priori and novel codes exploring communication behaviors, parental engagement, and interpersonal dynamics. RESULTS: Participating parents had children with various diagnoses. Only 15% of fathers and 5% of mothers reported education beyond primary school. Providers spoke 68% of words during psychoeducation and 85% of words during diagnosis conversations. Providers used supportive communication behaviors providing explanations, demonstrating verbal attentiveness, and soliciting questions and non-supportive behaviors including paternalistic talk. Parental participation was considered active when they asked questions, expressed hopes or concerns, or asserted their opinions, and non-active when participation was limited to brief responses to closed-ended questions. Supportive provider communication often encouraged active participation; non-supportive communication did not. Furthermore, active parental participation prompted supportive communication from providers, while non-active participation did not. CONCLUSIONS: Our findings highlight the bidirectional nature of effective communication, establishing that provider communication styles both influence and are influenced by parental participation, and emphasizing the importance of supportive provider communication for patient-centered care.
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Comunicación , Neoplasias , Padres , Relaciones Profesional-Familia , Investigación Cualitativa , Humanos , Masculino , Femenino , Niño , Neoplasias/psicología , Neoplasias/diagnóstico , Neoplasias/terapia , Guatemala , Adulto , Padres/psicología , Adolescente , Preescolar , Lactante , Oncología Médica , Personal de Salud/psicologíaRESUMEN
PURPOSE: Stigma is an understudied barrier to health care acceptance in pediatric oncology. We sought to explore the stigma experience, including its impact on cancer treatment decision making, and identify strategies to mitigate stigma for patients with osteosarcoma and retinoblastoma in Guatemala, Jordan, and Zimbabwe. METHODS: Participants included caregivers, adolescent patients (age 12-19 years), and health care clinicians. A semistructured interview guide based on The Health Stigma and Discrimination Framework (HSDF) was adapted for use at each site. Interviews were conducted in English, Spanish, Arabic, or Shona, audio-recorded, translated, and transcribed. Thematic analysis focused on stigma practices, experiences, outcomes, drivers, mitigators, and interventions. RESULTS: We conducted 56 interviews (28 caregivers, 19 health care clinicians, nine patients; 20 in Guatemala, 21 in Jordan, 15 in Zimbabwe). Major themes were organized into categories used to adapt the HSDF to global pediatric cancer care. Themes were described similarly across all sites, ages, and diagnoses, with specific cultural nuances noted. Pediatric cancer stigma was depicted as an isolating and emotional experience beginning at diagnosis and including internalized and associative stigma. Stigma affected decision making and contributed to negative outcomes including delayed diagnosis, treatment abandonment, regret, and psychosocial fragility. Overcoming stigma led to positive outcomes including resilience, treatment adherence, pride, and advocacy. Identified stigma drivers and mitigators were linked to potential interventions. CONCLUSION: Participants describe a shared stigma experience that transcends geography, cultural context, age, and diagnosis. Stigma manifestations have the potential to impact medical decision making and affect long-term psychological outcomes. Stigma assessment tools and interventions aimed at stigma mitigation including educational initiatives and support groups specific to pediatric cancer should be the focus of future research.
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Osteosarcoma , Retinoblastoma , Estigma Social , Humanos , Adolescente , Guatemala , Niño , Femenino , Masculino , Zimbabwe , Retinoblastoma/psicología , Adulto Joven , Osteosarcoma/psicología , Adulto , Cuidadores/psicologíaRESUMEN
The leafhopper Dalbulus maidis is a harmful pest that causes severe damage to corn crops. Conventional chemical pesticides have negative environmental impacts, emphasizing the need for alternative solutions. RNA interference (RNAi) is a more specific and environmentally friendly method for controlling pests and reducing the negative impacts of current pest management practices. Previous studies have shown that orally administered double-stranded RNA (dsRNA) is less effective than injection protocols in silencing genes. This study focuses on identifying and understanding the role of double-stranded ribonucleases (dsRNases) in limiting the efficiency of oral RNAi in D. maidis. Three dsRNases were identified and characterized, with Dmai-dsRNase-2 being highly expressed in the midgut and salivary glands. An ex vivo degradation assay revealed significant nuclease activity, resulting in high instability of dsRNA when exposed to tissue homogenates. Silencing Dmai-dsRNase-2 improved the insects' response to the dsRNA targeting the gene of interest, providing evidence of dsRNases involvement in oral RNAi efficiency. Therefore, administering both dsRNase-specific and target gene-specific-dsRNAs simultaneously is a promising approach to increase the efficiency of oral RNAi and should be considered in future control strategies.
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Hemípteros , Ribonucleasas , Animales , Ribonucleasas/genética , Ribonucleasas/metabolismo , Interferencia de ARN , Zea mays/genética , Zea mays/metabolismo , Hemípteros/genética , Hemípteros/metabolismo , Insectos/genética , ARN Bicatenario/genéticaRESUMEN
BACKGROUND: In high-income countries, hope facilitates parental coping and builds the clinical relationship between families of children with cancer and their clinicians. However, the manifestation of hope in low- and middle-income countries (LMICs) remains poorly understood. Our study explores Guatemalan parents' experiences with hope during the pediatric oncology diagnostic process and aims to identify discrete actions clinicians take to support hope. METHODS: This qualitative study utilized audio-recordings of the diagnostic process and an additional semi-structured interview for 20 families of children with cancer at Unidad Nacional de Oncología Pediátrica in Guatemala. Spanish audio-recordings were translated into English, transcribed, and coded using a priori and novel codes. Thematic content analysis using constant comparative methods explored parents' hopes and concerns. RESULTS: At diagnosis, Guatemalan parents expressed both hopes and concerns related to the entire cancer continuum. Throughout the diagnostic process, hope grew as concerns were alleviated. Clinicians supported hope by creating a supportive environment, providing information, affirming religious beliefs, and empowering parents. These strategies helped parents shift their focus from fear and uncertainty toward hope for their child's future. Parents expressed that establishing hope improved mood, promoted acceptance, and enabled them to care for themselves and their children. CONCLUSION: These results confirm the relevance of supporting hope in pediatric oncology settings in LMICs and suggest that culture informs hope-related needs. Supporting hope is critical across cultures and can be integrated into clinical conversation using the four processes identified by our results.
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Neoplasias , Padres , Humanos , Niño , Neoplasias/diagnóstico , Neoplasias/terapia , Oncología Médica , Comunicación , MiedoRESUMEN
OBJECTIVES: To examine treatment decision-making priorities and experiences among parents of children with cancer in Guatemala. SETTING: This study was conducted at Guatemala's National Pediatric Cancer Center in Guatemala City. PARTICIPANTS: Spanish-speaking parents of paediatric patients (≤18 years of age) diagnosed with any form of cancer within the 8 weeks prior to study enrolment. The quantitative portion of this study included 100 parent participants; the qualitative component included 20 parents. Most participants were Catholic or Evangelical Spanish-speaking mothers. OUTCOMES: Priorities and experiences of cancer treatment decision-making including decision-making role and experienced regret. RESULTS: A range of paediatric ages and cancer diagnoses were included. Most Guatemalan parents surveyed (70%) made decisions about their child's cancer together and almost all (94%) without input from their community. Surveyed parents predominately preferred shared decision-making with their child's oncologist (76%), however 69% agreed it was best not to be provided with many options. Two-thirds of surveyed parents (65%) held their preferred role in decision-making, with fathers more likely to hold their preferred role than mothers (p=0.02). A small number of parents (11%) experienced heightened decisional regret, which did not correlate with socio-demographic characteristics or preferred decision-making role. Qualitative results supported quantitative findings, demonstrating a decision-making process that emphasised trust and honesty. CONCLUSIONS: Guatemalan parents preferred to make decisions with their medical team and appreciated providers who were honest and inclusive, but directive about decisions. This study reinforces the importance of the provider-parent relationship and encourages clinicians in all settings to ask about and honour each parent's desired role in decision-making.
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Toma de Decisiones , Neoplasias , Niño , Femenino , Guatemala , Humanos , Lactante , Neoplasias/terapia , Padres , Encuestas y CuestionariosRESUMEN
BACKGROUND: The corn leafhopper Dalbulus maidis is the main vector of important stunting pathogens that affect maize production. Currently, there are no effective methods available to manage this pest without adverse impact on the environment. In this context, genomic-based technologies such as RNA interference (RNAi) provide a more environmentally friendly pest control strategy. Therefore, we aimed to assess the application of RNAi in D. maidis and determine the function of a candidate gene related to insect reproduction and propagation. RESULTS: We have characterized the core RNAi genes and evaluated the functionality of the RNAi machinery. We assessed the potential of RNAi technology in D. maidis via injection or ingestion of double-stranded RNA (dsRNA) to adult females. We chose Bicaudal C (BicC) as a target gene due to its important role during insect oogenesis. Administration of dsRNABicC caused significant reductions in the transcript levels (fold changes up to 170 times) and ovipositions. Phenotypic analysis of the ovaries revealed alterations in oocyte development, providing additional confirmation for our results and supporting the idea that Dmai-BicC is a key player of D. maidis oogenesis. CONCLUSION: This is, to our knowledge, the first report of efficient RNAi in D. maidis. We believe our findings provide a starting point for future control strategies against one of the most important maize pests in the Americas. © 2022 Society of Chemical Industry.
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Hemípteros , Zea mays , Animales , Femenino , Hemípteros/genética , Control de Plagas , Interferencia de ARN , ARN Bicatenario/genética , Zea mays/genéticaRESUMEN
INTRODUCTION: Fatalistic cancer beliefs may contribute to delayed diagnosis and poor outcomes, including treatment abandonment, for children with cancer. This study explored Guatemalan parents' cancer beliefs during initial paediatric cancer communication, and the sociocultural and contextual factors that influence these beliefs. METHODS: Twenty families of children with cancer were included in this study. We audio-recorded psychosocial conversations with psychologists and diagnostic conversations with oncologists, then conducted semi-structured interviews with parents to explore the evolution of their cancer beliefs. Audio-recordings were transcribed and translated from Spanish into English, with additional review in both languages by bilingual team members. All 60 transcripts were thematically analysed using a priori and novel codes. RESULTS: Guatemalan parents' beliefs evolve as they learn about cancer through various sources. Sources of information external to the cancer centre, including prior experiences with cancer, media exposure, community discussion and clinical encounters, contribute to pre-existing beliefs. Many parents' pre-existing cancer beliefs are fatalistic; some are influenced by Mayan spirituality. Sources internal to the cancer centre include psychologists and oncologists, other providers, other patients and families. Psychologists acknowledge pre-existing beliefs and deliver cancer education using verbal explanations and hand-drawings. Oncologists provide diagnostic information and outline treatment plans. Both support hope by providing a path toward cure. Parents' lived experience is a culmination of sources and simultaneously independent. Ultimately most parents arrive at an understanding of cancer that is consistent with an allopathic medical model and offers optimism about outcomes. CONCLUSION: An interdisciplinary communication process that includes cancer education, is attentive to pre-existing beliefs, and supports hope may encourage acceptance of the allopathic medical model and need for treatment. Providers in settings of all resource levels may be able to use these techniques to support cross-cultural cancer communication, reduce treatment abandonment and improve therapy adherence.
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Neoplasias , Niño , Comunicación , Guatemala , Humanos , Neoplasias/diagnóstico , Neoplasias/terapia , Padres , Investigación CualitativaRESUMEN
Drug encapsulation in nanocarriers such as polymeric nanoparticles (Nps) may help to overcome the limitations associated with cannabinoids. In this study, the authors' work aimed to highlight the use of electrospraying techniques for the development of carrier Nps of anandamide (AEA), an endocannabinoid with attractive pharmacological effects but underestimated due to its unfavourable physicochemical and pharmacokinetic properties added to its undesirable effects at the level of the central nervous system. The authors characterised physicochemically and evaluated in vitro biological activity of anandamide/É-polycaprolactone nanoparticles (Nps-AEA/PCL) obtained by electrospraying in epithelial cells of the human proximal tubule (HK2), to prove the utility of this method and to validate the biological effect of Nps-AEA/PCL. They obtained particles from 100 to 900â nm of diameter with a predominance of 200-400â nm. Their zeta potential was -20 ± 1.86â mV. They demonstrated the stable encapsulation of AEA in Nps-AEA/PCL, as well as its dose-dependent capacity to induce the expression of iNOS and NO levels and to decrease the Na+/K+ ATPase activity in HK2 cells. Obtaining Nps-AEA/PCL by electrospraying would represent a promising methodology for a novel AEA pharmaceutical formulation development with optimal physicochemical properties, physical stability and biological activity on HK2 cells.
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Ácidos Araquidónicos/química , Endocannabinoides/química , Nanopartículas/química , Poliésteres/química , Alcamidas Poliinsaturadas/química , Ácidos Araquidónicos/farmacología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Fenómenos Químicos , Estabilidad de Medicamentos , Técnicas Electroquímicas , Endocannabinoides/farmacología , Humanos , Nanopartículas/toxicidad , Óxido Nítrico/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Alcamidas Poliinsaturadas/farmacología , ATPasa Intercambiadora de Sodio-Potasio/metabolismoRESUMEN
BACKGROUND: The kidney and cardiovascular system are closely related to each other during the modulation of the cardiovascular homeostasis. However, the search for new alternatives for the treatment and diagnosis of cardiovascular diseases does not take into account this relationship, so their evaluation results and the advantages offered by their global and integrative analysis are wasted. For example, a variety of receptors that are overexpressed in both pathologies is large enough to allow expansion in the search for new molecular targets and ligands. Nanotechnology offers pharmacological targeting strategies to kidney, heart, and blood vessels for overcoming one of the essential restrictions of traditional cardiovascular therapies the ones related to their unspecific pharmacodynamics distribution in these critical organs. RECENT FINDINGS: Drug or contrast agent nano-targeting for treatment or diagnosis of atherosclerosis, thrombosis, renal cancer or fibrosis, glomerulonephritis, among other renal, cardiac and blood vessels pathologies would allow an increase in their efficacy and a reduction of their side effects. Such effects are possible because, through pharmacological targeting, the drug is mainly found at the desired site. Review Purpose: In this mini-review, active, passive, and physical targeting strategies of several nanocarriers that have been assessed and proposed for the treatment and diagnosis of different cardiovascular diseases, are being addressed.
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Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Renales/diagnóstico , Enfermedades Renales/tratamiento farmacológico , Fármacos Cardiovasculares/administración & dosificación , Enfermedades Cardiovasculares/metabolismo , Sistemas de Liberación de Medicamentos , Diagnóstico Precoz , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Humanos , Enfermedades Renales/metabolismo , Ligandos , Nanopartículas , Fármacos Renales/administración & dosificaciónRESUMEN
Cardiovascular disease is currently not adequately managed and has become one of the main causes of morbidity and mortality worldwide. Current therapies are inadequate in terms of preventing its progression. There are several limitations, such as poor oral bioavailability, side effects, low adherence to treatment, and high dosage frequency of formulations due to the short half-life of the active ingredients used, among others. This review aims to highlight the most relevant aspects of the relationship between the cardiovascular system and the endocannabinoid system, with special attention to the possible translational effect of the use of anandamide in cardiovascular health. The deep and detailed knowledge of this interaction, not always beneficial, and that for years has gone unnoticed, is essential for the development of new therapies. We discuss the most recent and representative results obtained in the field of basic research, referring to the aforementioned subject, emphasizing fundamentally the main role of nitric oxide, renal physiology and its deregulation in pathological processes.
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Ácidos Araquidónicos/uso terapéutico , Agonistas de Receptores de Cannabinoides/uso terapéutico , Enfermedades Cardiovasculares/tratamiento farmacológico , Sistema Cardiovascular/efectos de los fármacos , Endocannabinoides/uso terapéutico , Alcamidas Poliinsaturadas/uso terapéutico , Receptores de Cannabinoides/efectos de los fármacos , Animales , Ácidos Araquidónicos/efectos adversos , Agonistas de Receptores de Cannabinoides/efectos adversos , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/metabolismo , Enfermedades Cardiovasculares/fisiopatología , Sistema Cardiovascular/metabolismo , Sistema Cardiovascular/fisiopatología , Endocannabinoides/efectos adversos , Humanos , Óxido Nítrico/metabolismo , Alcamidas Poliinsaturadas/efectos adversos , Receptores de Cannabinoides/metabolismo , Transducción de Señal/efectos de los fármacos , Resultado del TratamientoRESUMEN
BACKGROUND: Treatment refusal and abandonment are major causes of treatment failure for children with cancer in low- and middle-income countries (LMICs), like Guatemala. This study identified risk factors for and described the intervention that decreased abandonment. METHODS: This was a retrospective study of Guatemalan children (0-18 years) with cancer treated at the Unidad Nacional de Oncología Pediátrica (UNOP), 2001-2008, using the Pediatric Oncology Network Database. Treatment refusal was a failure to begin treatment and treatment abandonment was a lapse of 4 weeks or longer in treatment. The impact of medicina integral, a multidisciplinary psychosocial intervention team at UNOP was evaluated. Cox proportional hazards analysis identified the effect of demographic and clinical factors on abandonment. Kaplan-Meier analysis estimated the survival. RESULTS: Of 1,789 patients, 21% refused or abandoned treatment. Abandonment decreased from 27% in 2001 to 7% in 2008 following the implementation of medicina integral. Factors associated with increased risk of refusal and abandonment: greater distance to the centre (P < 0.001), younger age (P = 0.017) and earlier year of diagnosis (P < 0.001). Indigenous race/ethnicity (P = 0.002) was associated with increased risk of abandonment alone. Abandonment correlated with decreased overall survival: 0.57 ± 0.02 (survival ± standard error) for those who completed therapy versus 0.06 ± 0.02 for those who abandoned treatment (P < 0.001) at 8.3 years. CONCLUSION: This study identified distance, age, year of diagnosis and indigenous race/ethnicity as risk factors for abandonment. A multidisciplinary intervention reduced abandonment and can be replicated in other LMICs.
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Neoplasias/mortalidad , Neoplasias/terapia , Negativa al Tratamiento , Adolescente , Cuidados Posteriores , Niño , Preescolar , Supervivencia sin Enfermedad , Femenino , Guatemala/epidemiología , Humanos , Lactante , Masculino , Estudios Retrospectivos , Tasa de SupervivenciaRESUMEN
Six batches of Oaxaca cheese (a Mexican pasta filata cheese) from 3 dairy plants were sampled and vacuum-packaged at 8°C up to 24d. Counts of principal microbial groups, pH, levels of sugars, organic acids, lipolytic and proteolytic indices, and texture, color, and meltability values of cheeses were studied at d 1, 8, 16 and 24 of storage. A descriptive sensory analysis of selected taste, odor, and texture characteristics was also carried out. The main changes in the cheeses during the storage were decreases in pH, hardness, elasticity, and whiteness, and an increase in meltability. Neither lipolytic nor proteolytic activities were evident during the storage of cheeses. Storage time resulted in a gradual quality loss of unmelted cheeses. This loss of quality might be related to the decrease of hardness and the appearance off-flavors.
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Queso/análisis , Queso/microbiología , Microbiología de Alimentos , Refrigeración , Almacenamiento de Alimentos , México , VacioRESUMEN
Health education is essential not only for preventing illnesses but also for knowing how to act when disease comes. In countries where the education system is inefficient for most of the population and where health issues are often ignored or mistreated because of ignorance or well-intended but ineffective belief in nature's energy and magic, it is important that people have access to truthful information about health issues. Such access allows them to act adequate knowledge and also to learn ways to avoid illness by changing their daily habits into a "healthy way of living." Approaching the young population is a way to achieve this objective. The program described here considers the education of both majority (indigenous) and minority (non indigenous) populations. It approaches the communication of information in such a way that it involves the participants in the "making" of the education. The participants actively interact with didactic material that allows them to experience "hands on" the issues about cancer and healthy living. It is intended to have a profound impact on the participant, so that he/she will remember the "education" not only as information but also as an experience. The program includes specific material for the indigenous population, which is based on their idiosyncrasy (corn plants) so that they can more easily understand the concepts. In Guatemala, UNOP (Unidad Nacional de Oncologia Pediatrica) is the only institution that provides a quality integral service for the majority of the entire children-with-cancer population. UNOP and the Psychology Department are interested in the development and implementation of education programs such as this where the participant not only learns but also experiences information about this disease and its prevention.
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Diversidad Cultural , Evaluación Educacional/métodos , Educación en Salud/métodos , Neoplasias/prevención & control , Conducta de Reducción del Riesgo , Adolescente , Guatemala , Humanos , Masculino , Neoplasias/terapiaRESUMEN
The renin-angiotensin system (RAS) has been implicated in pulmonary hypertension and pulmonary fibrosis. In the present study, we examined the effects of maternal exposure to captopril (2.85 mg/kg/day) during late pregnancy (G13-G21) on postnatal rat lung development. Treatment with captopril during late pregnancy caused a significant decrease in ACE activity in P0 rats. Body weight decreased at P0 (p<0.001), P8 and P15 (p<0.01) in captopril-treated rats. Lung weight of P0 and P8 pups was lower in treated-animals (p<0.05). Lungs from captopril-treated animals showed impaired alveolar formation, with enlarged distal airway spaces at P8, P15 and P30. Interalveolar wall distance measured by mean linear intercept increased in treated vs. age-matched animals at P8, P15 (p<0.001) and P30 (p<0.05) resembling new bronchopulmonary dysplasia. In control animals, the proliferating cell nuclear antigen (PCNA) marker was higher at P0 and then drops gradually, while in captopril-treated animals PCNA marker remains higher at all stages studied. α-Smooth muscle actin (α-SMA), a marker of fibroblast differentiation into myofibroblasts, was higher at the tips of developing secondary septa in captopril-treated lungs at P8 and P15. The increased expression of PCNA and α-SMA in treated pups suggest that beyond the effect caused by captopril, the developing lungs have the capacity to recover once the treatment was stopped. Taking together the low weight, histomorphological changes and increased expression of cellular markers caused by ACE inhibition during late pregnancy, it appears that the RAS could be an intrinsic factor involved in secondary septa formation during lung development.
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Captopril/efectos adversos , Pulmón/efectos de los fármacos , Peptidil-Dipeptidasa A/metabolismo , Efectos Tardíos de la Exposición Prenatal/inducido químicamente , Actinas/metabolismo , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Animales Recién Nacidos , Biomarcadores/metabolismo , Diferenciación Celular , Proliferación Celular , Femenino , Pulmón/embriología , Pulmón/crecimiento & desarrollo , Pulmón/patología , Masculino , Miofibroblastos/metabolismo , Tamaño de los Órganos , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo , Efectos Tardíos de la Exposición Prenatal/patología , Antígeno Nuclear de Célula en Proliferación/metabolismo , Ratas , Ratas Wistar , Receptor de Angiotensina Tipo 1/metabolismo , Sistema Renina-Angiotensina , Pérdida de PesoRESUMEN
La relación entre la audición y el desarrollo del lenguaje ha sido ampliamente demostrada, se aprende a hablar imitando los sonidos oídos y dándole la interpretación que oralmente los padres enseñan. Por ello, todos los países se están esforzando por realizar un tamizado universal en neonatos. El Estado de Chile, en un primer esfuerzo por detectar tempranamente las sorderas, está aplicando un tamizado auditivo a neonatos de alto riesgo. No hay en Chile estudio sobre las causas de sorderas, por lo cual se decidió investigar sobre esta materia en un grupo de niños sordos que estudia en alguna de las 4 escuelas especiales de Santiago. Conociendo las causas de sorderas congénitas y las de instalación en la infancia temprana, posibilita su prevención en el control del embarazo y de niño sano. Objetivo: Establecer las causas de sorderas profundas, según los conocimientos de sus padres o tutor legal y ficha escolar, en niños y jóvenes estudiantes de escuelas especiales para sordos. Material y método: En este estudio observacional, el universo fueron todos los niños que asisten a 4 escuelas especiales para sordos en Santiago. La muestra estuvo constituida por 315 casos que representan al 92 por ciento del universo. Se revisaron las fichas escolares de estos niños y la información se contrastó y completó con una entrevista a los padres o tutores. Conclusiones: El 63 por ciento de los niños presentaba sordera congénita, entre ellos el 9 por ciento fue por infección materna. Del total de la población, el 41.5 por ciento presentó sordera congénita de causa desconocida; el 13 por ciento fue adquirida por meningitis y en el 5.8 por ciento de los casos por prematurez.
The relationship between hearing and language development has been widely demonstrated, as children learn to speak by imitating sounds and interpreting them as they are orally taught by their parents. Because of this, countries are trying to put more emphasis on universal screening of newborns. In Chile, the first efforts of early detection of deafness have been in screening high risk newborns. En Chile there are no studies on the causes of deafness, and for this reason the present study seeks to investigate this issue in a group of Deaf children in special schools in Santiago. Understanding the causes of congenital and early childhood deafness allows for better prevention during pregnancy and early childhood. Objective: Establish the causes of severe deafness, according to the knowledge of parents or legal guardians and school records, in young students in special schools for the Deaf. Materials and Methods: In this observational study, the universe consisted of all children that attend 4 special schools for the Deaf in Santiago. The sample consisted of 315 cases, which represent 92 percent of the universe. School records were examined and information was contrasted and completed with and interview with parents or guardians. Conclusions: 63 percent of children suffered from congenital deafness, 9 percent of those due to infection during pregnancy. In 41.5 percent of all cases the cause of deafness was unknown. 13 percent was due to meningitis, and 5.8 percent was due to prematurity.
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Humanos , Masculino , Femenino , Niño , Sordera/epidemiología , Sordera/etiología , Distribución por Edad y Sexo , Edad de Inicio , Audiometría , Chile , Transmisión Vertical de Enfermedad Infecciosa , Tamizaje Masivo , Meningitis/complicaciones , Nacimiento Prematuro , Índice de Severidad de la Enfermedad , Factores SocioeconómicosRESUMEN
The development of knock-out mice for Angiotensin II (Ang II) AT(2) receptors, which exhibited altered exploratory behavior, prompted us to investigate the cerebellum and brainstem. We evaluated the effect of stimulation/inhibition of Ang II receptors on hindbrain development, in offspring (postnatal days P0, P8) of pregnant rats treated during late pregnancy (Ang II, Losartan or PD123319, 1 mg/kg/day). Receptor localization by autoradiography showed in P0 and P8 hindbrains, that most structures expressed AT(2) subtype: cerebellar cortex, cerebellar nuclei, genu facial nucleus, inferior colicullus, inferior olive. In the cerebellar cortex, [(125)I]Ang II AT(2) binding was predominant, while low AT(1) binding was observed in adjacent layers of the cerebellar cortex. Blockade of AT(2) receptors with PD123319 increased binding in cerebellar nuclei (p<0.05) and brainstem nuclei at P0, P8, in correlation with increased AT(2) receptor expression by RT-PCR. The enlarged external granular layer (EGL) in PD123319-treated P0 pups contrast with the significant decrease in Ang II binding (p<0.001) in the cerebellar cortex. Blockade of AT(2) receptors during late pregnancy seems to arrest cerebellar cortex development in P0 animals. On the contrary, increased AT(2) binding was observed in cerebellar cortex and DTg nucleus in PD123319-treated P8 animals (p<0.001). Ang II treatment leads to increased binding in the brainstem. In spite of the low doses of Ang II antagonists used, treatments were performed during a time-frame critical for hindbrain development, leading to remarkable effects. The present study makes a contribution to understand the role of Ang II receptors during hindbrain development.
Asunto(s)
Bloqueadores del Receptor Tipo 1 de Angiotensina II/toxicidad , Animales Recién Nacidos/fisiología , Receptores de Angiotensina/metabolismo , Rombencéfalo/anatomía & histología , Animales , Autorradiografía , Femenino , Feto/metabolismo , Imidazoles/toxicidad , Losartán/toxicidad , Ratones , Embarazo , Piridinas/toxicidad , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Ratas , Ratas Wistar , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 2/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Rombencéfalo/crecimiento & desarrollo , Vasoconstrictores/toxicidadRESUMEN
Evidence suggests that Angiotensin II plays an important role in the complex process of renal organogenesis. Rat kidney organogenesis starts between E13-14 and lasts up to 2 weeks after birth. The present study demonstrates histologic modifications and changes in receptor localisation in animals born from mothers treated with Angiotensin II, Losartan or PD123319 (1.0 mg/kg/day) during late pregnancy. Angiotensin II-treated animals exhibited very well developed tubules in the renal medulla in coincidence with higher AT(1) binding. Control animals exhibited angiotensin AT(2) binding in the outer stripe of the outer medulla, while in the Angiotensin II-treated animals binding was observed to the inner stripe. In Angiotensin II-treated 1-week-old animals, the nephrogenic zone contained fewer immature structures, and more developed collecting tubules than control animals. Treatment with Losartan resulted in severe renal abnormalities. For newborn and 1-week-old animals, glomeruli exhibited altered shape and enlarged Bowman spaces, in concordance with a loss of [(125)I]Angiotensin II binding in the cortex. Blockade with PD123319 led to an enlarged nephrogenic zone with increased number of immature glomeruli, and less glomeruli in the juxtamedullary area. Autoradiography showed a considerable loss of AT(1) binding in the kidney cortex of PD123319-treated animals at both ages. The present results show for the first time histomorphological and receptor localisation alterations following treatment with low doses of Losartan and PD123319 during pregnancy. These observations confirm previous assumptions that in the developing kidney Angiotensin II exerts stimulatory effects through AT(1) receptors that might be counterbalanced by angiotensin AT(2) receptors.
Asunto(s)
Anomalías Inducidas por Medicamentos/patología , Bloqueadores del Receptor Tipo 1 de Angiotensina II/toxicidad , Bloqueadores del Receptor Tipo 2 de Angiotensina II , Riñón/anomalías , Preñez/fisiología , Envejecimiento/metabolismo , Angiotensina II/antagonistas & inhibidores , Angiotensina II/farmacología , Animales , Animales Recién Nacidos , Autorradiografía , Femenino , Imidazoles/toxicidad , Riñón/patología , Glomérulos Renales/efectos de los fármacos , Glomérulos Renales/patología , Losartán/toxicidad , Embarazo , Piridinas/toxicidad , Ratas , Ratas Wistar , Receptor de Angiotensina Tipo 1/metabolismo , Receptor de Angiotensina Tipo 2/metabolismo , Sistema Renina-Angiotensina/efectos de los fármacos , Sistema Renina-Angiotensina/fisiologíaRESUMEN
The viscacha (Lagostomus maximus maximus) is a seasonal rodent living in the Southern Hemisphere. The adult males exhibit an annual reproductive cycle characterized by a gonadal regression period during winter. In this study, we investigated the effects of bilateral enucleation and captivity on their annual reproductive cycle. Testicular volume relative to body weight was recorded monthly in intact and bilaterally enucleated animals placed under natural photoperiod, water, and food ad lib. and constant temperature. Testes and accessory organs were evaluated by qualitative and quantitative light microscopic studies. The intact animals showed an annual reproductive cycle with complete gonadal atrophy in the first year. In the second year, testicular regression was observed but attenuated in regard to that recorded in the first winter period, indicating that adaptive changes might be involved. Bilateral enucleation in the viscacha dampened and extended the period of its annual reproductive cycle. The results suggest that both conditions, constant captivity and enucleation, produced stimulatory effects on the reproductive system of this rodent. Furthermore, local control mechanisms might be responsible for the morphological differences observed in testes, epididymis, and seminal vesicles from both groups, which exhibited similar levels of serum testosterone. Finally, an intact retinohypothalamic-pineal axis and/or photoperiodic input would be necessary to maintain the reproductive cycle amplitude and timing in viscacha.
Asunto(s)
Chinchilla/fisiología , Reproducción/fisiología , Testículo/anatomía & histología , Animales , Argentina , Pesos y Medidas Corporales , Técnicas Histológicas , Masculino , Orquiectomía , Fotoperiodo , Estaciones del Año , Temperatura , Testosterona/sangreRESUMEN
Angiotensin II (Ang II) elicits a variety of physiological effects through specific Ang II receptors in numerous tissues. In addition, Ang II is a modulator of cellular growth and exerts a positive or negative effect on cell growth depending on which receptor subtype is activated. Expression of the intrarenal AT2 receptors occurs at its highest levels in the fetal kidney, with a rapid decline after birth. In the present paper, we performed a study on the signaling mechanism of Ang II receptors in rat fetal (E20) kidney, a rich source of AT2 receptors, where both Ang II receptor subtypes are present. Ang II induces Tyr-dephosphorylation of proteins in rat fetal kidney membranes. The response is dose-dependent, with a reduction of 20% with respect to the control (100%), signal that is completely reversed by Ang IIAT2 competitor PD123319. Orthovanadate, the inhibitor of phospho-Tyr-phosphatases (PTPase), reverts Ang II effect, suggesting the involvement of a protein tyrosine phosphatase. The peptide analog of Ang II, CGP42112, exhibits an agonist effect, which is dose-dependent. Thus, in rat fetal (E20) kidney, the Ang-induced protein Tyr-dephosphorylation of several proteins is mediated by AT2 receptors, mechanism that involves an orthovanadate sensitive PTPase.