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The domestication process of the common bean gave rise to six different races which come from the two ancestral genetic pools, the Mesoamerican (Durango, Jalisco, and Mesoamerica races) and the Andean (New Granada, Peru, and Chile races). In this study, a collection of 281 common bean landraces from Chile was analyzed using a 12K-SNP microarray. Additionally, 401 accessions representing the rest of the five common bean races were analyzed. A total of 2543 SNPs allowed us to differentiate a genetic group of 165 accessions that corresponds to the race Chile, 90 of which were classified as pure accessions, such as the bean types 'Tórtola', 'Sapito', 'Coscorrón', and 'Frutilla'. Our genetic analysis indicates that the race Chile has a close relationship with accessions from Argentina, suggesting that nomadic ancestral peoples introduced the bean seed to Chile. Previous archaeological and genetic studies support this hypothesis. Additionally, the low genetic diversity (π = 0.053; uHe = 0.53) and the negative value of Tajima' D (D = -1.371) indicate that the race Chile suffered a bottleneck and a selective sweep after its introduction, supporting the hypothesis that a small group of Argentine bean genotypes led to the race Chile. A total of 235 genes were identified within haplotype blocks detected exclusively in the race Chile, most of them involved in signal transduction, supporting the hypothesis that intracellular signaling pathways play a fundamental role in the adaptation of organisms to changes in the environment. To date, our findings are the most complete investigation associated with the origin of the race Chile of common bean.
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Phaseolus , Phaseolus/genética , Chile , Argentina , Domesticación , Pool de GenesRESUMEN
Mutations in the CLCN5 gene encoding the 2Cl- /1H+ exchanger ClC-5 are associated with Dent disease 1, an inherited renal disorder characterized by low-molecular-weight (LMW) proteinuria and hypercalciuria. In the kidney, ClC-5 is mostly localized in proximal tubule cells, where it is thought to play a key role in the endocytosis of LMW proteins. Here, we investigated the consequences of eight previously reported pathogenic missense mutations of ClC-5 surrounding the "proton glutamate" that serves as a crucial H+ -binding site for the exchanger. A complete loss of function was observed for a group of mutants that were either retained in the endoplasmic reticulum of HEK293T cells or unstainable at plasma membrane due to proteasomal degradation. In contrast, the currents measured for the second group of mutations in Xenopus laevis oocytes were reduced. Molecular dynamics simulations performed on a ClC-5 homology model demonstrated that such mutations might alter ClC-5 protonation by interfering with the water pathway. Analysis of clinical data from patients harboring these mutations demonstrated no phenotype/genotype correlation. This study reveals that mutations clustered in a crucial region of ClC-5 have diverse molecular consequences in patients with Dent disease 1, ranging from altered expression to defects in transport.
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Enfermedad de Dent , Protones , Canales de Cloruro/química , Enfermedad de Dent/genética , Enfermedad de Dent/metabolismo , Enfermedades Genéticas Ligadas al Cromosoma X , Ácido Glutámico , Células HEK293 , Humanos , NefrolitiasisRESUMEN
TASK-3 is a two-pore domain potassium (K2P) channel highly expressed in the hippocampus, cerebellum, and cortex. TASK-3 has been identified as an oncogenic potassium channel and it is overexpressed in different cancer types. For this reason, the development of new TASK-3 blockers could influence the pharmacological treatment of cancer and several neurological conditions. In the present work, we searched for novel TASK-3 blockers by using a virtual screening protocol that includes pharmacophore modeling, molecular docking, and free energy calculations. With this protocol, 19 potential TASK-3 blockers were identified. These molecules were tested in TASK-3 using patch clamp, and one blocker (DR16) was identified with an IC50 = 56.8 ± 3.9 µM. Using DR16 as a scaffold, we designed DR16.1, a novel TASK-3 inhibitor, with an IC50 = 14.2 ± 3.4 µM. Our finding takes on greater relevance considering that not many inhibitory TASK-3 modulators have been reported in the scientific literature until today. These two novel TASK-3 channel inhibitors (DR16 and DR16.1) are the first compounds found using a pharmacophore-based virtual screening and rational drug design protocol.
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Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Diseño de Fármacos , Células HEK293 , Humanos , Simulación del Acoplamiento Molecular , Bloqueadores de los Canales de Potasio/farmacocinéticaRESUMEN
A1899 is a potent and selective inhibitor of the two-pore domain potassium (K2P) channel TASK-1. It was previously reported that A1899 acts as an open-channel blocker and binds to residues of the P1 and P2 regions, the M2 and M4 segments, and the halothane response element. The recently described crystal structures of K2P channels together with the newly identified side fenestrations indicate that residues relevant for TASK-1 inhibition are not purely facing the central cavity as initially proposed. Accordingly, the TASK-1 binding site and the mechanism of inhibition might need a re-evaluation. We have used TASK-1 homology models based on recently crystallized K2P channels and molecular dynamics simulation to demonstrate that the highly potent TASK-1 blocker A1899 requires binding to residues located in the side fenestrations. Unexpectedly, most of the previously described residues that interfere with TASK-1 blockade by A1899 project their side chains toward the fenestration lumina, underlining the relevance of these structures for drug binding in K2P channels. Despite its hydrophobicity, A1899 does not seem to use the fenestrations to gain access to the central cavity from the lipid bilayer. In contrast, binding of A1899 to residues of the side fenestrations might provide a physical "anchor", reflecting an energetically favorable binding mode that after pore occlusion stabilizes the closed state of the channels.
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Benzamidas/farmacología , Bencenoacetamidas/farmacología , Simulación de Dinámica Molecular , Proteínas del Tejido Nervioso/antagonistas & inhibidores , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Animales , Benzamidas/química , Bencenoacetamidas/química , Sitios de Unión , Humanos , Interacciones Hidrofóbicas e Hidrofílicas , Proteínas del Tejido Nervioso/química , Proteínas del Tejido Nervioso/metabolismo , Canales de Potasio de Dominio Poro en Tándem/química , Canales de Potasio de Dominio Poro en Tándem/metabolismoRESUMEN
Proton-gated TASK-3 K(+) channel belongs to the K(2P) family of proteins that underlie the K(+) leak setting the membrane potential in all cells. TASK-3 is under cooperative gating control by extracellular [H(+)]. Use of recently solved K(2P) structures allows us to explore the molecular mechanism of TASK-3 cooperative pH gating. Tunnel-like side portals define an extracellular ion pathway to the selectivity filter. We use a combination of molecular modeling and functional assays to show that pH-sensing histidine residues and K(+) ions mutually interact electrostatically in the confines of the extracellular ion pathway. K(+) ions modulate the pK(a) of sensing histidine side chains whose charge states in turn determine the open/closed transition of the channel pore. Cooperativity, and therefore steep dependence of TASK-3 K(+) channel activity on extracellular pH, is dependent on an effect of the permeant ion on the channel pH(o) sensors.
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Activación del Canal Iónico , Canales de Potasio de Dominio Poro en Tándem/química , Animales , Sitios de Unión , Relación Dosis-Respuesta a Droga , Electrofisiología/métodos , Cobayas , Humanos , Concentración de Iones de Hidrógeno , Iones , Potenciales de la Membrana , Ratones , Modelos Moleculares , Conformación Molecular , Técnicas de Placa-Clamp , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Probabilidad , Protones , Electricidad EstáticaRESUMEN
Common bean (Phaseolus vulgaris L.) is the primary grain legume cultivated worldwide for direct human consumption due to the high nutritional value of its seeds and pods. The high protein content of common beans highlights it as the most promising source of plant-based protein for the food industry. Additionally, landraces of common bean have great variability in nutritional traits, which is necessary to increase the nutritional quality of elite varieties. Therefore, the main objective of this study was to nutritionally characterize 23 Chilean landraces and 5 commercial varieties of common bean to identify genotypes with high nutritional value that are promising for the food industry and for genetic improvement programs. The landrace Phv23 ('Palo') was the most outstanding with high concentrations of minerals such as P (7.53 g/kg), K (19.8 g/kg), Mg (2.43 g/kg), Zn (52.67 mg/kg), and Cu (13.67 mg/kg); essential amino acids (364.8 mg/g protein); and total proteins (30.35 g/100 g seed). Additionally, the landraces Phv9 ('Cimarrón'), Phv17 ('Juanita'), Phv3 ('Araucano'), Phv8 ('Cabrita/Señorita'), and Phv4 ('Arroz') had a high protein content. The landrace Phv24 ('Peumo') stood out for its phenolic compounds (TPC = 218.1 mg GA/100 g seed) and antioxidant activity (ORAC = 22,167.9 µmol eq trolox/100 g extract), but it has moderate to low mineral and protein concentrations. In general, the concentration of nutritional compounds in some Chilean landraces was significantly different from the commercial varieties, highlighting their high nutritional value and their potential use for the food industry and for genetic improvement purposes.
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In terms of safe and healthy food, beans play a relevant role. This crop belongs to the species of Phaseolusvulgaris L., being the most consumed legume worldwide, both for poor and developed countries, the latter seek to direct their diet to healthy feeding, mainly low in fat. Phaseolus vulgaris L. stands out in this area-an important source of protein, vitamins, essential minerals, soluble fiber, starch, phytochemicals, and low in fat from foods. This species has been attributed many beneficial properties for health; it has effects on the circulatory system, immune system, digestive system, among others. It has been suggested that Phaseolus vulgaris L. has a relevant role in the prevention of cardiovascular events, the main cause of mortality and morbidity worldwide. Conversely, the decrease in the consumption of this legume has been related to an increase in the prevalence of cardiovascular diseases. This review will allow us to relate the nutritional level of this species with cardiovascular events, based on the correlation of the main bioactive compounds and their role as cardiovascular protectors, in addition to revealing the main mechanisms that explain the cardioprotective effects regulated by the bioactive components.
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Common bean is one of the most important legumes produced and consumed worldwide because it is a highly valuable food for the human diet. However, its production is mainly carried out by small farmers, who obtain average grain yields below the potential yield of the species. In this sense, numerous mapping studies have been conducted to identify quantitative trait loci (QTL) associated with yield components in common bean. Meta-QTL (MQTL) analysis is a useful approach to combine data sets and for creating consensus positions for the QTL detected in independent studies. Consequently, the objective of this study was to perform a MQTL analysis to identify the most reliable and stable genomic regions associated with yield-related traits of common bean. A total of 667 QTL associated with yield-related traits reported in 21 different studies were collected. A total of 42 MQTL associated with yield-related traits were identified, in which the average confidence interval (CI) of the MQTL was 3.41 times lower than the CIs of the original QTL. Most of the MQTL (28) identified in this study contain QTL associated with yield and phenological traits; therefore, these MQTL can be useful in common bean breeding programs. Finally, a total of 18 candidate genes were identified and associated with grain yield within these MQTL, with functions related to ubiquitin ligase complex, response to auxin, and translation elongation factor activity.
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A genotyping by sequencing (GBS) approach was used to analyze the organization of genetic diversity in V. pubescens and V. chilensis. GBS identified 4675 and 4451 SNPs/INDELs in two papaya species. The cultivated orchards of V. pubescens exhibited scarce genetic diversity and low but significant genetic differentiation. The neutrality test yielded a negative and significant result, suggesting that V. pubescens suffered a selective sweep or a rapid expansion after a bottleneck during domestication. In contrast, V. chilensis exhibited a high level of genetic diversity. The genetic differentiation among the populations was slight, but it was possible to distinguish the two genetic groups. The neutrality test indicated no evidence that natural selection and genetic drift affect the natural population of V. chilensis. Using the Carica papaya genome as a reference, we identified critical SNPs/INDELs associated with putative genes. Most of the identified genes are related to stress responses (salt and nematode) and vegetative and reproductive development. These results will be helpful for future breeding and conservation programs of the Caricaceae family.
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BACKGROUND: Adenosine is a natural nucleoside present in a variety of organs and tissues, where it acts as a modulator of diverse physiological and pathophysiological processes. These actions are mediated by at least four G protein-coupled receptors, which are widely and differentially expressed in tissues. Interestingly, high concentrations of adenosine have been reported in a variety of tumors. In this context, the final output of adenosine in tumorigenesis will likely depend on the constellation of adenosine receptors expressed by tumor and stromal cells. Notably, activation of the A3 receptor can reduce the proliferative capacity of various cancer cells. OBJECTIVE: This study aimed to describe the anti-proliferative effects of two previously synthesized adenosine derivatives with A3 agonist action (compounds 2b and 2f) through in vitro assays. METHODS: We used gastric and breast cancer cell lines expressing the A3 receptor as in vitro models and theoretical experiments for molecular dynamics and determination of ADME properties. RESULTS: The antiproliferative effects of adenosine derivatives (after determining IC50 values) were comparable or even higher than those described for IB-MECA, a commercially available A3 agonist. Among possible mechanisms involved, apoptosis was found to be induced in MCF-7 cells but not in AGS or MDA-MB-231 cells. Surprisingly, we were unable to observe cellular senescence induction upon treatment with compounds 2b and 2f in any of the cell lines studied, although we cannot rule out other forms of cell cycles exit at this point. CONCLUSION: Both adenosine derivatives showed antiproliferative effects on gastric and breast cancer cell lines, and were able to induce apoptosis, at least in the MCF-7 cell line. Further studies will be necessary to unveil receptor specificity and mechanisms accounting for the antiproliferative properties of these novel semi-synthetic compounds.
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Neoplasias de la Mama , Receptor de Adenosina A3 , Adenosina/farmacología , Apoptosis , Neoplasias de la Mama/tratamiento farmacológico , Ciclo Celular , Femenino , Humanos , Receptor de Adenosina A3/metabolismoRESUMEN
Chemical structures of selective blockers of TASK channels contain aromatic groups and amide bonds. Using this rationale, we designed and synthesized a series of compounds based on 3-benzamidobenzoic acid. These compounds block TASK-1 channels by binding to the central cavity. The most active compound is 3-benzoylamino-N-(2-ethyl-phenyl)-benzamide or F3, blocking TASK-1 with an IC50 of 148 nM, showing a reduced inhibition of TASK-3 channels and not a significant effect on different K+ channels. We identified putative F3-binding sites in the TASK-1 channel by molecular modeling studies. Mutation of seven residues to A (I118A, L122A, F125A, Q126A, L232A, I235A, and L239A) markedly decreased the F3-induced inhibition of TASK-1 channels, consistent with the molecular modeling predictions. F3 blocks cell proliferation and viability in the MCF-7 cancer cell line but not in TASK-1 knockdown MCF-7 cells, indicating that it is acting in TASK-1 channels. These results indicated that TASK-1 is necessary to drive proliferation in the MCF-7 cancer cell line.
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Neoplasias , Humanos , Relación Estructura-Actividad , Sitios de Unión , Proliferación Celular , Modelos Moleculares , Células MCF-7RESUMEN
Withaferin A (WFA), a C5,C6-epoxy steroidal lactone isolated from the medicinal plant Withania somnifera (L.) Dunal, inhibits growth of tumor cells in different cancer types. However, the mechanisms underlying the effect of WFA on tumor cells are not fully understood. In the present study, we evaluated the blockade of TASK-3 channels by WFA in TASK-3-expressing HEK-293 cells. Explore if the WFA-mediated TASK-3 blockade can be used as a pharmacological tool to decrease the cell viability in cancer cells. A combination of functional experiments (patch-clamp, gene downregulation, overexpression and pharmacological inhibition) and molecular docking analysis were used to get insights into the mechanism by which the inhibition of TASK-3 by WFA affects the growth and viability of cancer cells. Withaferin A was found to inhibit the activity of TASK-3 channels. The inhibitory effect of Withaferin A on TASK-3 potassium currents was dose-dependent and independent of voltage. Molecular modeling studies identified putative WFA-binding sites in TASK-3 channel involved the channel blockade. In agreements with the molecular modeling predictions, mutation of residues F125 to A (F125A), L197 to V (L197â¯V) and the double mutant F125A-L197â¯V markedly decreased the WFA-induced inhibition of TASK-3. Finally, the cytotoxic effect of WFA was tested in MDA-MB-231 human breast cancer cells transfected with TASK-3 or shRNA that decreases TASK-3 expression. Together, our results show that the cytotoxic effect of WFA on fully transformed MDA-MB-231 cells depends on the expression of TASK-3. Herein, we also provide insights into the mechanism of TASK-3 inhibition by WFA.
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Antineoplásicos Fitogénicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proliferación Celular/efectos de los fármacos , Bloqueadores de los Canales de Potasio/farmacología , Canales de Potasio de Dominio Poro en Tándem/antagonistas & inhibidores , Witanólidos/farmacología , Antineoplásicos Fitogénicos/metabolismo , Sitios de Unión , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Células HEK293 , Humanos , Potenciales de la Membrana , Bloqueadores de los Canales de Potasio/metabolismo , Canales de Potasio de Dominio Poro en Tándem/genética , Canales de Potasio de Dominio Poro en Tándem/metabolismo , Unión Proteica , Transducción de Señal , Witanólidos/metabolismoRESUMEN
Since 1929, several researchers have conducted studies in relation to the nucleoside of adenosine (1) mainly distribution identifying, characterizing their biological importance and synthetic chemistry to which this type of molecule has been subjected to obtain multiple of its derivatives. The receptors that interact with adenosine and its derivatives, called purinergic receptors, are classified as A1, A2A, A2B and A3. In the presence of agonists and antagonists, these receptors are involved in various physiological processes and diseases. This review describes and compares some of the synthetic methods that have been developed over the last 30 years for obtaining some adenosine derivatives, classified according to substitution processes, complexation, mating and conjugation. Finally, we mention that although the concentrations of these nucleosides are low in normal tissues, they can increase rapidly in pathophysiological conditions such as hypoxia, ischemia, inflammation, trauma and cancer. In particular, the evaluation of adenosine derivatives as adjunctive therapy promises to have a significant impact on the treatment of certain cancers, although the transfer of these results to clinical practice requires a deeper understanding of how adenosine regulates the process of tumorigenesis.
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Adenosina/análogos & derivados , Antineoplásicos/síntesis química , Adenosina/metabolismo , Adenosina/uso terapéutico , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Compuestos Aza/química , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/patología , Glioblastoma/tratamiento farmacológico , Glioblastoma/patología , Humanos , Receptores Purinérgicos P1/química , Receptores Purinérgicos P1/metabolismo , Ácidos Sulfónicos/químicaRESUMEN
OBJECTIVE: The purpose of this study was to identify factors that predict parent satisfaction (PS) with their child with autism spectrum disorder (ASD)'s visit to a hospital emergency department (ED) or urgent care (UC) center. METHODS: Parents recruited through a national database whose child (3-21 years; N = 378) with ASD had been treated in an ED/UC center within the previous 3 years completed an anonymous on-line questionnaire. They answered questions about whether they were satisfied overall with the visit and the care provided, their demographics, patient characteristics, their expectations and preparation for the visit, and the ED/UC center experience itself, including their observations of staff interpersonal and communication skills (ICSs) and behaviors, and whether the patient was disruptive (D). Multiple correspondence analysis (MCA) was used to demonstrate the relative effects of individual variables on PS. RESULTS: Among the 10 most important determinants of PS with the visit were the 9 assessed staff ICS behaviors. These were followed by shorter than expected waiting time and the patient not being disruptive (ND) during the visit. PS was not associated with any of the 3 measures of patient disability severity (ASD subtype, communicative competence, or restrictiveness of educational placement), whether the patient is hyperreactive to sensory stimuli, reason for the visit, or parent's education. CONCLUSION: PS with an ED/UC center visit when the patient has autism depends mostly on the quality of staff interactions with the patient and family. It is important for ED/UC center administrators to ensure that staff understand how to interact and communicate effectively with patients with ASD and their families.
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Atención Ambulatoria , Trastorno del Espectro Autista/terapia , Servicio de Urgencia en Hospital , Padres , Satisfacción del Paciente , Relaciones Profesional-Familia , Relaciones Profesional-Paciente , Adolescente , Adulto , Atención Ambulatoria/estadística & datos numéricos , Niño , Preescolar , Servicio de Urgencia en Hospital/estadística & datos numéricos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente/estadística & datos numéricos , Adulto JovenRESUMEN
Se realizó un estudio observacional, descriptivo, retrospectivo en el Hospital de Oshakati durante el período enero - diciembre de 2009, con el objetivo de determinar las características de los niños que son maltratados desde su infancia hasta 15 años de edad, datos que se obtuvieron mediante una encuesta diseñada, dirigida a familiares, niños y médicos de las comunidades pertenecientes a la región objeto de estudio. El universo de estudio quedó constituido por 390 niños que acudieron al hospital y la muestra son todos los casos detectados (146). Predominó el sexo masculino, el tipo de maltrato físico encontrado fueron los trastornos nutricionales; además fueron obligados a abandonar la escuela para realizar labores domésticas; en el sexual, los tocamientos fueron un aspecto importante; la mayoría de los niños deseaban que sus familias fueran diferentes, una proporción bastante similar se sentían parte importante de su familia y señalaron recibir maltrato. Sugerimos divulgar los resultados a los gestores en salud y realizar estudios de mayor complejidad para profundizar en esta temática(AU)
An observational-descriptive- retrospective study was carried out in the Oshakati Hospital from January - December of 2009, with the aim of determining the characteristics of child abuse up to 15 years old. This data was obtained through a survey designed for the family members, doctors and children belonging to the community under study. The universe was formed by 390 children that came to the hospital and the sample consisted on the detected cases (146). The male sex prevailed and the type of physical abuse was the nutritional disorders, besides these children were forced to leave school and do housework, and the sexual abuse was also an important aspect. The majority of the children wished that the family members were different. A similar amount felt themselves as important parts of their families. We suggest then to spread out the results of this investigation to the health agents and to perform studies of greater complexity in order to improve this topic(EU)
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Humanos , Niño , Maltrato a los Niños/clasificación , Maltrato a los Niños/historia , Maltrato a los Niños/psicología , Violencia Doméstica/psicología , Epidemiología Descriptiva , Estudios Retrospectivos , Estudios Observacionales como AsuntoRESUMEN
Se realizo un estudio descriptivo, de corte transversal, con el objetivo de conocer la prevalencia de la lactancia materna en el municipio Jesús Menéndez y los factores relacionados con la misma durante el año 2010. El universo de estudio estuvo constituido por 477 niños menores de 6 meses del territorio mencionado. Se aplicó una encuesta a las madres. Se utilizaron las siguientes variables: edad, consejo popular, área de salud, tiempo de lactancia materna exclusiva, enfermedades de la madre, causas de la introducción de otro tipo de leche, enfermedades del niño, conocimiento de la medre y familia sobre lactancia materna. Se utilizó la estadística descriptiva para el análisis de los datos. Entre los principales resultados está, que el área de salud con mejor prevalencia de la lactancia materna es el Área de Salgacero, con 89 (AU), y por consejo popular el más afectado es Pueblo Viejo, con 45,9 por ciento. Entre los factores de riesgo que más influyeron están la poca promoción de salud a madres y familiares, en el 99,1 por ciento; se demostró el desconocimiento sobre la lactancia materna por parte de la madre y la familia, en un 86,3 por ciento, así como estrés en la madre. Se recomienda la realización de actividades de promoción de salud comunitaria que incluya a la familia (AU)
A descriptive study of cross- sectional research was carried out with the aim of knowing the prevalence of breastfeeding and its related factors in 2010 in the municipality of Jesús Menéndez. The universe of study consisted of 477 children under 6 months of age in the above-mentioned territory. A survey was applied among the mothers of those children, with variables such as age, Popular Council to which they belong, health area, duration of exclusive breastfeeding, mothers´ illnesses, reasons for the use of other types of milk, childrens illnesses, and the knowledge of the mothers and family about breastfeeding. The descriptive statistics technique was used for data analysis. Among the main results is the finding that Salgacero Area- with 89 por center - is the area with highest prevalence in breastfeeding and the worst Popular Council was Pueblo Viejo with 45,9 por center. Poor promotion activities-99,1 por center - with the families and pregnant women was one of the principal risk factors; the mothers and families´ lack of knowledge about breastfeeding was shown in a 86,3 por center as well as stress in the mother. The recommendations from the study include community promotion activities with the families (AU)