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1.
Mol Biol Evol ; 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38652808

ABSTRACT

In fungi, fusion between individuals leads to localized cell death, a phenomenon termed heterokaryon incompatibility. Generally, the genes responsible for this incompatibility are observed to be under balancing selection resulting from negative frequency-dependent selection. Here, we assess this phenomenon in Aspergillus fumigatus, a human pathogenic fungus with a very low level of linkage disequilibrium as well as an extremely high crossover rate. Using complementation of auxotrophic mutations as an assay for hyphal compatibility, we screened sexual progeny for compatibility to identify genes involved in this process, called het genes. In total, 5/148 (3.4%) offspring were compatible with a parent and 166/2142 (7.7%) sibling pairs were compatible, consistent with several segregating incompatibility loci. Genetic mapping identified five loci, four of which could be fine mapped to individual genes, of which we tested three through heterologous expression, confirming their causal relationship. Consistent with long-term balancing selection, trans-species polymorphisms were apparent across several sister species, as well as equal allele frequencies within A. fumigatus. Surprisingly, a sliding window genome-wide population-level analysis of an independent dataset did not show increased Tajima's D near these loci, in contrast to what is often found surrounding loci under balancing selection. Using available de novo assemblies, we show that these balanced polymorphisms are restricted to several hundred base pairs flanking the coding sequence. In addition to identifying the first het genes in an Aspergillus species, this work highlights the interaction of long-term balancing selection with rapid linkage disequilibrium decay.

2.
PLoS Biol ; 21(9): e3002278, 2023 09.
Article in English | MEDLINE | ID: mdl-37708139

ABSTRACT

Sexual reproduction involving meiosis is essential in most eukaryotes. This produces offspring with novel genotypes, both by segregation of parental chromosomes as well as crossovers between homologous chromosomes. A sexual cycle for the opportunistic human pathogenic fungus Aspergillus fumigatus is known, but the genetic consequences of meiosis have remained unknown. Among other Aspergilli, it is known that A. flavus has a moderately high recombination rate with an average of 4.2 crossovers per chromosome pair, whereas A. nidulans has in contrast a higher rate with 9.3 crossovers per chromosome pair. Here, we show in a cross between A. fumigatus strains that they produce an average of 29.9 crossovers per chromosome pair and large variation in total map length across additional strain crosses. This rate of crossovers per chromosome is more than twice that seen for any known organism, which we discuss in relation to other genetic model systems. We validate this high rate of crossovers through mapping of resistance to the laboratory antifungal acriflavine by using standing variation in an undescribed ABC efflux transporter. We then demonstrate that this rate of crossovers is sufficient to produce one of the common multidrug resistant haplotypes found in the cyp51A gene (TR34/L98H) in crosses among parents harboring either of 2 nearby genetic variants, possibly explaining the early spread of such haplotypes. Our results suggest that genomic studies in this species should reassess common assumptions about linkage between genetic regions. The finding of an unparalleled crossover rate in A. fumigatus provides opportunities to understand why these rates are not generally higher in other eukaryotes.


Subject(s)
ATP-Binding Cassette Transporters , Aspergillus fumigatus , Humans , Aspergillus fumigatus/genetics , Antifungal Agents , Biological Transport , Eukaryota , Meiosis/genetics
3.
Plant J ; 112(5): 1298-1315, 2022 12.
Article in English | MEDLINE | ID: mdl-36239071

ABSTRACT

Photosynthesis is a key process in sustaining plant and human life. Improving the photosynthetic capacity of agricultural crops is an attractive means to increase their yields. While the core mechanisms of photosynthesis are highly conserved in C3 plants, these mechanisms are very flexible, allowing considerable diversity in photosynthetic properties. Among this diversity is the maintenance of high photosynthetic light-use efficiency at high irradiance as identified in a small number of exceptional C3 species. Hirschfeldia incana, a member of the Brassicaceae family, is such an exceptional species, and because it is easy to grow, it is an excellent model for studying the genetic and physiological basis of this trait. Here, we present a reference genome of H. incana and confirm its high photosynthetic light-use efficiency. While H. incana has the highest photosynthetic rates found so far in the Brassicaceae, the light-saturated assimilation rates of closely related Brassica rapa and Brassica nigra are also high. The H. incana genome has extensively diversified from that of B. rapa and B. nigra through large chromosomal rearrangements, species-specific transposon activity, and differential retention of duplicated genes. Duplicated genes in H. incana, B. rapa, and B. nigra that are involved in photosynthesis and/or photoprotection show a positive correlation between copy number and gene expression, providing leads into the mechanisms underlying the high photosynthetic efficiency of these species. Our work demonstrates that the H. incana genome serves as a valuable resource for studying the evolution of high photosynthetic light-use efficiency and enhancing photosynthetic rates in crop species.


Subject(s)
Brassica rapa , Brassicaceae , Humans , Brassicaceae/metabolism , Photosynthesis/genetics , Crops, Agricultural , Phenotype
4.
Rev Chil Pediatr ; 90(1): 78-88, 2019.
Article in English | MEDLINE | ID: mdl-31095222

ABSTRACT

INTRODUCTION: Becoming a first-time father is an important change in the life of men and families. Studies on the subject show that these kinds of changes have the power to put life into perspective. Being an involved father has a deep meaning for the child and the family. OBJECTIVE: To explore the experience of becoming a first-time father during the child first year of the life. SUBJECTS AND METHODS: A qualitative systematic review was conducted in 2014 in three stages, based on the Joanna Briggs Institute Method for Qualitative Systematic Reviews (QSR). The stages used in this QSR were: establishing the question, determining the type of studies to be included, defining the evaluation criteria, and synthesizing the data. Papers that assessed clinical prognoses were considered such as first-time parenting experience and child care during the first year of life. Only primary qualitative studies including ethnography, phenomenology, narrative analysis, and action research were con sidered. RESULTS: Three meta-syntheses were obtained from the analysis: 1) fatherhood adjustment process, 2) paternal role development, and 3) being an active father. The path towards adoption and the fulfillment of the paternal role is mediated by different processes that are consolidated during the child first year of life. CONCLUSIONS: The results support the idea that fathers want to be active parti cipants in the care of their children, that public policies should consider both parents equal in terms of their parenting responsibilities, and that the protection of the family and the family environment is a priority as a health promotion intervention.


Subject(s)
Fathers/psychology , Parent-Child Relations , Parenting/psychology , Attitude , Emotional Adjustment , Humans , Male , Qualitative Research , Role
5.
Rev. chil. pediatr ; 90(1): 78-88, 2019. tab, graf
Article in English | LILACS | ID: biblio-990889

ABSTRACT

INTRODUCTION: Becoming a first-time father is an important change in the life of men and families. Studies on the subject show that these kinds of changes have the power to put life into perspective. Being an involved father has a deep meaning for the child and the family. OBJECTIVE: To explore the experience of becoming a first-time father during the child first year of the life. SUBJECTS AND METHODS: A qualitative systematic review was conducted in 2014 in three stages, based on the Joanna Briggs Institute Method for Qualitative Systematic Reviews (QSR). The stages used in this QSR were: establishing the question, determining the type of studies to be included, defining the evaluation criteria, and synthesizing the data. Papers that assessed clinical prognoses were considered such as first-time parenting experience and child care during the first year of life. Only primary qualitative studies including ethnography, phenomenology, narrative analysis, and action research were con sidered. RESULTS: Three meta-syntheses were obtained from the analysis: 1) fatherhood adjustment process, 2) paternal role development, and 3) being an active father. The path towards adoption and the fulfillment of the paternal role is mediated by different processes that are consolidated during the child first year of life. CONCLUSIONS: The results support the idea that fathers want to be active parti cipants in the care of their children, that public policies should consider both parents equal in terms of their parenting responsibilities, and that the protection of the family and the family environment is a priority as a health promotion intervention.


INTRODUCCIÓN: Ser padre por primera vez es un cambio importante en la vida del hombre y la familia. Los estudios en torno al tema demuestran que este tipo de cambios tienen la capacidad de poner la vida en perspectiva. Ser un padre participativo tiene un significado profundo para el niño/a y la familia. OBJETIVO: Explorar la experiencia de ser padre por primera vez durante el primer año de la vida del hijo/a. SUJETOS Y MÉTODO: Se realizó una revisión sistemática cualitativa en 2014 en 3 etapas, basado en el Joanna Briggs Institute Method para Revisiones Sistemáticas Cualitativas (QSR). Las etapas usadas en este QSR fueron: establecimiento de la pregunta, determinar el tipo de estudios a incluir, definir los criterios de evaluación, y realizar la síntesis de los datos. Se consideraron manuscritos que evaluaran los pronósticos clínicos: experiencia de ser padre por primera vez y cuidados del niños durante el primer año de vida. Solo estudios cualitativos primarios incluyendo estudios de etnografía, fenomenología, análisis de narrativa e investigación de acciones fueron considerados. RESULTADOS: Se obtuvieron tres meta-síntesis del análisis: 1) proceso de ajuste a la paternidad; 2) desarrollo del rol paterno y 3) ser un padre activo. El camino hacia la adopción y el cumplimiento del rol paterno está mediado por diversos procesos que durante el primer año de vida del niño/a se consolidan. CONCLUSIONES: Los resultados apoyan la propuesta de que los padres desean ser protagonistas del cuidado de sus hijos/as, que las políticas públicas deben considerar a ambos padres como iguales en términos de sus responsabilidades de crianza, y que la protección de la familia y el entorno familiar es una priori dad como intervención de promoción de salud.


Subject(s)
Humans , Male , Parent-Child Relations , Parenting/psychology , Fathers/psychology , Role , Attitude , Qualitative Research , Emotional Adjustment
6.
Front Plant Sci ; 9: 1721, 2018.
Article in English | MEDLINE | ID: mdl-30542361

ABSTRACT

Phospholipase C (PLC) has been suggested to play important roles in plant stress and development. To increase our understanding of PLC signaling in plants, we have started to analyze knock-out (KO), knock-down (KD) and overexpression mutants of Arabidopsis thaliana, which contains nine PLCs. Earlier, we characterized PLC2, PLC3 and PLC5. Here, the role of PLC7 is functionally addressed. Promoter-GUS analyses revealed that PLC7 is specifically expressed in the phloem of roots, leaves and flowers, and is also present in trichomes and hydathodes. Two T-DNA insertion mutants were obtained, i.e., plc7-3 being a KO- and plc7-4 a KD line. In contrast to earlier characterized phloem-expressed PLC mutants, i.e., plc3 and plc5, no defects in primary- or lateral root development were found for plc7 mutants. Like plc3 mutants, they were less sensitive to ABA during stomatal closure. Double-knockout plc3 plc7 lines were lethal, but plc5 plc7 (plc5/7) double mutants were viable, and revealed several new phenotypes, not observed earlier in the single mutants. These include a defect in seed mucilage, enhanced leaf serration, and an increased tolerance to drought. Overexpression of PLC7 enhanced drought tolerance too, similar to what was earlier found for PLC3-and PLC5 overexpression. In vivo 32Pi-labeling of seedlings and treatment with sorbitol to mimic drought stress, revealed stronger PIP2 responses in both drought-tolerant plc5/7 and PLC7-OE mutants. Together, these results show novel functions for PLC in plant stress and development. Potential molecular mechanisms are discussed.

7.
J Hepatol ; 69(6): 1250-1259, 2018 12.
Article in English | MEDLINE | ID: mdl-30138685

ABSTRACT

BACKGROUND & AIMS: Patients with decompensated cirrhosis on the waiting list for liver transplantation (LT) commonly develop complications that may preclude them from reaching LT. Circulatory dysfunction leading to effective arterial hypovolemia and activation of vasoconstrictor systems is a key factor in the pathophysiology of complications of cirrhosis. The aim of this study was to investigate whether treatment with midodrine, an alpha-adrenergic vasoconstrictor, together with intravenous albumin improves circulatory dysfunction and prevents complications of cirrhosis in patients awaiting LT. METHODS: A multicenter, randomized, double-blind, placebo-controlled trial (NCT00839358) was conducted, including 196 consecutive patients with cirrhosis and ascites awaiting LT. Patients were randomly assigned to receive midodrine (15-30 mg/day) and albumin (40 g/15 days) or matching placebos for one year, until LT or drop-off from inclusion on the waiting list. The primary endpoint was incidence of any complication (renal failure, hyponatremia, infections, hepatic encephalopathy or gastrointestinal bleeding). Secondary endpoints were mortality, activity of endogenous vasoconstrictor systems and plasma cytokine levels. RESULTS: There were no significant differences between both groups in the probability of developing complications of cirrhosis during follow-up (p = 0.402) or one-year mortality (p = 0.527). Treatment with midodrine and albumin was associated with a slight but significant decrease in plasma renin activity and aldosterone compared to placebo (renin -4.3 vs. 0.1 ng/ml.h, p < 0.001; aldosterone -38 vs. 6 ng/dl, p = 0.02, at week 48 vs. baseline). Plasma norepinephrine only decreased slightly at week 4. Neither arterial pressure nor plasma cytokine levels changed significantly. CONCLUSIONS: In patients with cirrhosis awaiting LT, treatment with midodrine and albumin, at the doses used in this study, slightly suppressed the activity of vasoconstrictor systems, but did not prevent complications of cirrhosis or improve survival. LAY SUMMARY: Patients with cirrhosis who are on the liver transplant waiting list often develop complications which prevent them from receiving a transplant. Circulatory dysfunction is a key factor behind a number of complications. This study was aimed at investigating whether treating patients with midodrine (a vasoconstrictor) and albumin would improve circulatory dysfunction and prevent complications. This combined treatment, at least at the doses administered in this study, did not prevent the complications of cirrhosis or improve the survival of these patients.


Subject(s)
Albumins/therapeutic use , Liver Cirrhosis/complications , Liver Cirrhosis/drug therapy , Liver Transplantation , Midodrine/therapeutic use , Shock/prevention & control , Vasoconstrictor Agents/therapeutic use , Adult , Aged , Albumins/administration & dosage , Aldosterone/blood , Ascites , Double-Blind Method , Female , Follow-Up Studies , Humans , Hyponatremia/etiology , Hyponatremia/prevention & control , Kaplan-Meier Estimate , Liver Cirrhosis/mortality , Male , Middle Aged , Midodrine/administration & dosage , Norepinephrine/blood , Renal Insufficiency/etiology , Renal Insufficiency/prevention & control , Renin/blood , Treatment Outcome , Vasoconstrictor Agents/administration & dosage
8.
Respiration ; 90(6): 474-80, 2015.
Article in English | MEDLINE | ID: mdl-26484660

ABSTRACT

BACKGROUND: The MPOWER strategy encourages suitable monitoring of the tobacco epidemic among health professionals in all countries. OBJECTIVE: To analyse the prevalence of and attitudes towards tobacco use among Spanish health professionals. METHODS: A study was conducted based on an online survey. The study population consisted of health professionals (primary care physicians, specialist physicians and nurses). The questionnaire used included questions about tobacco consumption, knowledge of and attitudes towards smoking. The sample size was calculated according to a database with 9,500 e-mail addresses and listings of health centres and hospitals all over Spain. Statistical analysis was done using the SPSS software programme. RESULTS: The study group comprised a total of 612 health professionals: 322 were women (52.6%), 196 were nurses and 416 were physicians. 11.7% of health professionals were smokers (9.6% regular smokers and 2.1% occasional smokers) and 41.3% were ex-smokers. Within the group of daily smokers, differences were observed between the nurses and the physicians: 11.2 versus 8.9% (p = 0.009). Smoking was recognized as a chronic disorder by 58.2% of health professionals, and 54.6% knew that the most effective intervention to help quit is a combination of psychological and pharmacological treatment. 56% of health professionals always asked their patients about their tobacco consumption. CONCLUSIONS: 11.7% of Spanish health professionals are smokers. We found that they have low knowledge about strategies to quit smoking and that there is a low level of therapeutic intervention on smokers.


Subject(s)
Attitude of Health Personnel , Nurses/statistics & numerical data , Physicians/statistics & numerical data , Smoking/epidemiology , Adult , Aged , Clinical Competence , Female , Humans , Male , Middle Aged , Prevalence , Smoking Cessation , Spain/epidemiology , Surveys and Questionnaires
9.
BMC Fam Pract ; 11: 23, 2010 Mar 18.
Article in English | MEDLINE | ID: mdl-20298557

ABSTRACT

BACKGROUND: The global mortality caused by cardiovascular disease increases with weight. The Framingham study showed that obesity is a cardiovascular risk factor independent of other risks such as type 2 diabetes mellitus, dyslipidemia and smoking. Moreover, the main problem in the management of weight-loss is its maintenance, if it is achieved. We have designed a study to determine whether a group motivational intervention, together with current clinical practice, is more efficient than the latter alone in the treatment of overweight and obesity, for initial weight loss and essentially to achieve maintenance of the weight achieved; and, secondly, to know if this intervention is more effective for reducing cardiovascular risk factors associated with overweight and obesity. METHODS: This 26-month follow up multi-centre trial, will include 1200 overweight/obese patients. Random assignment of the intervention by Basic Health Areas (BHA): two geographically separate groups have been created, one of which receives group motivational intervention (group intervention), delivered by a nurse trained by an expert phsychologist, in 32 group sessions, 1 to 12 fortnightly, and 13 to 32, monthly, on top of their standard program of diet, exercise, and the other (control group), receiving the usual follow up, with regular visits every 3 months. DISCUSSION: By addressing currently unanswered questions regarding the maintenance in weight loss in obesity/overweight, upon the expected completion of participant follow-up in 2012, the IMOAP trial should document, for the first time, the benefits of a motivational intervention as a treatment tool of weight loss in a primary care setting. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01006213.


Subject(s)
Cardiovascular Diseases/prevention & control , Motivation , Overweight/therapy , Primary Prevention/methods , Psychotherapy, Group , Combined Modality Therapy , Diet, Reducing , Exercise , Follow-Up Studies , Humans , Obesity/complications , Obesity/psychology , Obesity/therapy , Overweight/complications , Overweight/psychology , Treatment Outcome , United States
12.
Santiago de Chile; Chile 21; 2005. 22 p. (Colección Ideas, 6, 52).
Monography in Spanish | LILACS | ID: lil-447988

Subject(s)
Humans , Public Policy , Chile , Poverty
13.
Psicol. rev. (Belo Horizonte) ; 10(14): 35-51, dez. 2003.
Article in Spanish | Index Psychology - journals | ID: psi-35836

ABSTRACT

Este articulo analiza a través de un ejercicio etnográfico los procesos de contrucción identitaria de los habitantes de barrios pobres y medios de la ciudad de Santiago de Chile. Se plantea que las identidades que alli se construyen son expresión de los procesos de segregación urbana de la ciudad de Santiago y ellas dan cuenta del debilitamiento de un modelo urbano asentado en la heterogeneidad social, la noción de espacio público y valores como la ciudadanía política y la integración social. Paradojalmente, esta misma segregación urbana abre también paso a un imaginario y una práctica de vida comunitaria y tribal que refuerza y protege al nosotros de la peligrosidad de los otros.(AU)


Subject(s)
Poverty , Social Isolation , Race Relations
14.
Psicol. rev. (Belo Horizonte) ; 10(14): 35-51, dez. 2003.
Article in Spanish | LILACS | ID: lil-509233

ABSTRACT

Este articulo analiza a través de un ejercicio etnográfico los procesos de contrucción identitaria de los habitantes de barrios pobres y medios de la ciudad de Santiago de Chile. Se plantea que las identidades que alli se construyen son expresión de los procesos de segregación urbana de la ciudad de Santiago y ellas dan cuenta del debilitamiento de un modelo urbano asentado en la heterogeneidad social, la noción de espacio público y valores como la ciudadanía política y la integración social. Paradojalmente, esta misma segregación urbana abre también paso a un imaginario y una práctica de vida comunitaria y tribal que refuerza y protege al nosotros de la peligrosidad de los otros.


This article results from a research carried out as an ethnographic exercise,focusing on the construction of social identity by dwellers of low- andmedium-income neighbourhoods in Santiago de Chile. It proposes thatthe identities built in that environment are one of the manifestations ofthe urban segregation processes characteristic of the city of Santiago. Italso presents those identities as an expression of the weakening of anurban model based on social heterogeneity, the notion of public spaceand values such as political citizenship and social integration. Paradoxi-cally, this same urban segregation also permits the development ofimageries and practices of community and tribal life that reinforce andprotect that entity named "Us" from the danger posed by the "Other"


Subject(s)
Social Isolation , Poverty , Race Relations
15.
Cienc. enferm ; 8(2): 73-78, dic. 2002. tab
Article in Spanish | LILACS | ID: lil-342353

ABSTRACT

Estudio descriptivo y transversal que analiza llamadas recibidas en un teléfono de un centro ambulatorio privado de atención de enfermería pediátrica, habilitado para recibir durante 24 horas consultas respecto al cuidado del niño. Los resultados muestran que, durante un año de funcionamiento, se recibieron 286 llamadas, la mayoría realizadas por la madre. El análisis de los motivos de consulta reveló que un 50 porciento de las consultas es por problemas de salud del niño: respiratorios, cólicos, dificultades para obrar; en segundo lugar, por problemas de lactancia y luego relacionados con cuidados básicos. La mayoría corresponden a problemas solucionables con medidas simples, aplicables en el hogar. En la totalidad de los casos la intervención de enfermería contribuyó a la solución, demostrándose que el teléfono es un importante sistema de apoyo para los cuidados en el hogar. Se sugiere el uso de este tipo de consulta como apoyo de enfermería en la crianza del niño menor de un año


Subject(s)
Humans , Nursing Care/methods , Child Rearing/trends , Remote Consultation , Telephone , Referral and Consultation , Remote Consultation
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