Reproductive isolation between wild and domesticated chaya (Cnidoscolus aconitifolius) in sympatry.

Reproductive isolation is a necessary condition for plant domestication in their domestication centre where crops co-occur with their wild progenitors. However, the identification of reproductive barriers and their relative contribution to reproductive isolation have been overlooked in plants under domestication. We assessed pre- and post-pollination reproductive barriers and their relative contribution to reproductive isolation between wild and domesticated chaya (Cnidoscolus aconitifolius) in its domestication centre. We found that wild and domesticated chaya both exhibit a high degree of reproductive isolation. However, the reproductive isolation barriers exhibited some asymmetry: while pre-pollination barriers (differential pollen production and pollinator specificity) were only detected in wild plants, post-pollination barriers (pollen-pistil incompatibility and/or failure to set fruit) were observed in both wild and domesticated plants. We conclude that complete reproductive isolation has evolved in sympatry in co-occurring domesticated and wild chaya.

Evaluación cualitativa de la calidad de vida en adolescentes con cáncer durante el tratamiento con la quimioterapia en un Hospital Federal de tercer nivel / Qualitative evaluation of the quality of life in adolescents with cancer during treatment with chemotherapy in a third level Federal Hospital

Introducción: El propósito fue evaluar la calidad de vida (CV) de los adolescentes con cáncer durante el tratamiento con quimioterapia para, dar cuenta de problemas prácticos de su realidad mediante la interpretación y comprensión desde su perspectiva y experiencias, ya que son las personas que padecen la enfermedad. Los hallazgos de este estudio permitirán implementar áreas de oportunidad así como reforzar estrategias de intervención durante el cuidado a la persona, con base en sus necesidades, además de contribuir al avance del conocimiento de enfermería. Objetivo: Evaluar cualitativamente la calidad de vida en adolescentes con cáncer durante el tratamiento con quimioterapia, a través de sus experiencias y percepciones. Metodología: El presente estudio es una evaluación cualitativa, la recolección fue mediante la observación participante y entrevista a profundidad. Los informantes fueron adolescentes hombres y mujeres de 10 a 14 años de edad, con cáncer, en tratamiento con quimioterapia, en el área de oncología hospitalización, de un hospital de tercer nivel. La muestra fue propositiva, determinada hasta alcanzar la saturación de datos. Se realizó un análisis sistemático, a través de la propuesta por Miles y Huberman en 1994, en tres etapas. Reducción de datos, disposición y transformación de datos y obtención y verificación de conclusiones. Resultados: Se presentan en dos partes; un marco teórico sobre evaluación cualitativa en enfermería y los cuatro temas, producto del estudio. 1) Confirmación del diagnóstico; 2) ¿Lástima o compasión?; 4) Temor y convivencia con la muerte; 4) El transcurrir de la vida diaria en el hospital. Conclusiones: Dentro de todo el proceso que viven los adolescentes se entrelazan experiencias y percepciones positivas y negativas de la enfermedad y el tratamiento, ellos sufren las consecuencias y viven en otras condiciones su calidad de vida, porque la enfermedad los confronta con la muerte.

Introduction: The purpose was to evaluate the quality of life (CV) of adolescents with cancer during chemotherapy treatment, to report practical problems of their reality through the interpretation and understanding from their perspective and experiences, since they are the people who suffer from disease. The findings of this study will allow the implementation of areas of opportunity as well as to reinforce intervention strategies during the care of the person, based on their needs, in addition to contributing to the advancement of nursing knowledge. Objective: To evaluate qualitatively the quality of life in adolescents with cancer during chemotherapy treatment, through their experiences and perceptions. Methodology: The present study is a qualitative evaluation, the collection was through participant observation and in-depth interview. The informants were adolescent males and females aged 10 to 14 years, with cancer, being treated with chemotherapy, in the area of oncology hospitalization, from a third level hospital. The sample was propositive, determined until data saturation was reached. A systematic analysis was made, through the proposal by Miles and Huberman in 1994, in three stages. Reduction of data, provision and transformation of data and obtaining and verification of conclusions. Results: A theoretical framework on qualitative nursing assessment and the four themes, which are the product of the study, are presented in two parts. 1) Confirmation of diagnosis; 2) Pity or compassion? 3) Fear and coexistence with death; 4) The passing of daily life in the hospital. Conclusions: Within the whole process that adolescents live, experiences and positive and negative perceptions of illness and treatment are intertwined, they suffer the consequences and live in other conditions their quality of life, because the disease confronts them with death.

Pollination system of the Pilosocereus leucocephalus columnar cactus (tribe Cereeae) in eastern Mexico.

It has been suggested that there is a geographic dichotomy in the pollination systems of chiropterophilous columnar cacti: in intra-tropical areas they are pollinated almost exclusively by bats, whereas in extratropical areas they are pollinated by bats, birds and bees. However, currently the studies are clumped both taxonomically (mainly Pachycereeae species) and geographically (mainly in the Tehuacan Valley and the Sonoran Desert). This clumping limits the possibility of generalising the pattern to other regions or cactus tribes. Only four of the 36 chiropterophilous cacti in Pilosocereus have been studied. Despite the tropical distribution of two Pilosocereus species, bees account for 40-100% of their fruit set. We examined how specialised is the pollination system of P. leucocephalus in eastern Mexico. As we studied tropical populations, we expected a bat-specialised pollination system. However, previous studies of Pilosocereus suggest that a generalised pollination system is also possible. We found that this cactus is mainly bat-pollinated (bats account for 33-65% of fruit set); although to a lesser degree, diurnal visitors also caused some fruit set (7-15%). Diurnal visitors were more effective in populations containing honeybee hives. P. leucocephalus is partially self-compatible (14-18% of fructification) but unable to set fruit without visitors. Despite the variation in pollination system, P. leucocephalus shows more affinity with other columnar cacti from tropical regions than with those from extratropical regions. Although we report here that a new species of tropical Pilosocereus is relatively bat-specialised, this Cereeae genus is more flexible in its pollination system than the Pachycereeae genera.

Hypercalciuria is the main renal abnormality finding in Human Immunodeficiency Virus-infected children in Venezuela.

Kidney involvement in children with Human Immunodeficiency Virus (HIV) infection is increasing in prevalence in parallel with the longer survival of HIV-infected patients and the side-effects of new antiretroviral drugs. However, there are only a few reports describing renal tubular disorders in HIV+ children. This is a cross-sectional, case series study evaluating kidney disease in 26 Venezuelan HIV-infected children. The study cohort consisted of 15 girls and 11 boys, with a median age of 5.9 years (25-75th percentile: 3.6-7.8), who had been treated with antiretrovirals for 2.8 +/- 0.4 years, Overall, the patients were short for their age and gender (Z-height: -3.1; 25-75th percentile: -4.94 to -1.98), and 15 showed signs of mild to moderate malnutrition. All of the children had a normal estimated glomerular filtration rate (136 +/- 22.6 ml/min/1.73 m2), and glomerular involvement was only observed in one patient with isolated proteinuria. None had nephromegaly. In contrast, tubular disorders were commonly found. Hypercalciuria was detected in 16 of the patients (UCa/Cr = 0.28; 25-75th percentile: 0.17-0.54 mg/mg), with five of these showing crystalluria. Eight children showed hyperchloremia, and three had frank metabolic acidosis. Kidney stones were absent in all, but one boy had bilateral medullary nephrocalcinosis. Conclusion, in Venezuelan children, HIV infection per se, or its specific treatment, was commonly associated with renal tubular dysfunction, especially hypercalciuria and acidosis, potentially leading to nephrocalcinosis and growth impairment. We recommend renal tubular evaluation during the follow-up of children with HIV infection.

[Urticaria and angioedema]. / Urticaria y angioedema.

Urticaria is considered a heterogeneous group of diseases that share different patterns of skin reactions. The wide diversity in urticaria subtypes have been identified and this reflects partial understanding of the causes or factors that trigger it, as well as the molecular and cellular mechanisms that are involved in their physiopathology. The objective of this article was to make an extensive review of the literature to be able to offer the readers a complete information and updating on the basic, ethiologic and physiophatologic mechanisms and mainly to make a special emphasis on diagnosis and treatment of urticaria, promoting the continuous medical education.

Precise mapping of quantitative trait loci for resistance to southern leaf blight, caused by Cochliobolus heterostrophus race O, and flowering time using advanced intercross maize lines.

The intermated B73 x Mo17 (IBM) population, an advanced intercross recombinant inbred line population derived from a cross between the maize lines B73 (susceptible) and Mo17 (resistant), was evaluated in four environments for resistance to southern leaf blight (SLB) disease caused by Cochliobolus heterostrophus race O. Two environments were artificially inoculated, while two were not inoculated and consequently had substantially lower disease pressure. Four common SLB resistance quantitative trait loci (QTL) were identified in all environments, two in bin 3.04 and one each in bins 1.10 and 8.02/3. There was no significant correlation between disease resistance and days to anthesis. A direct comparison was made between SLB QTL detected in two populations, independently derived from the same parental cross: the IBM advanced intercross population and a conventional recombinant inbred line population. Several QTL for SLB resistance were detected in both populations, with the IBM providing between 5 and, in one case, 50 times greater mapping resolution.

A molecular phylogeographic study based on DNA sequences from individual metacercariae of Paragonimus mexicanus from Guatemala and Ecuador.

A molecular phylogeographic study of Paragonimus mexicanus collected from Guatemala and Ecuador was performed. Genomic DNA was extracted from individual metacercariae, and two gene regions (partial mitochondrial cytochrome c oxidase subunit 1 (CO1) and the second internal transcribed spacer of the nuclear ribosomal gene repeat (ITS2)) were amplified by the polymerase chain reaction (PCR). Sequences segregated in a phylogenetic tree according to their geographic origins. ITS2 sequences from Ecuador and Guatemala differed at only one site. Pairwise distances among CO1 sequences within a country were always lower than between countries. Nevertheless, genetic distances between countries were less than between geographical forms of P. westermani that have been suggested to be distinct species. This result suggests that populations from Guatemala and Ecuador are genetically differentiated perhaps at the level of subspecies.

Reacción inmediata al latex: comparación entre la prueba cutánea y la determinación de IgE por ELISA / Immediate reaction to the latex: comparison between the cutaneous test and IgEïs determination for ELISA

Antecedentes: la respuesta de hipersensibilidad tipo 1 mediada por IgE al látex depende de la intensidad de la exposición y de la predisposición genética. Las manifestaciones clínicas son urticaria, rinoconjuntivitis, asma y anafilaxia. Objetivo: conocer la frecuencia de la reactividad cutánea inmediata al látex por medio de pruebas cutáneas por prick, en pacientes pediátricos con síntomas de alergia. Es un estudio clínico piloto prospectivo realizado en un plazo de seis meses en el cual se incluyeron 629 pacientes de 1 a 15 años, con diagnóstico de alergia, de los cuales 30 (4.76 por ciento) resultaron con prueba cutánea positiva de acuerdo con la clasificación de Aas a antígeno de látex (15 hombres, 15 mujeres) con edad media de 8.9 años. El grupo de edad de 1-5 años correspondió al 1.85 por ciento, el de 6 a 10 años al 6.21 por ciento y el de 11 a 15 años, 8.9 por ciento. Además, el grupo control (prueba cutánea negativa) lo integraron 30 niños con las mismas características de sexo, edad y diagnóstico. El 73.3 por ciento tenía antecedente de atopia, 63 por ciento diagnóstico de rinitis y asma, sólo rinitis 13 por ciento, asma 20 por ciento, conjuntivitis 20 por ciento, dermatitis atópica y anafilaxia 3.3 por ciento, urticaria 6.6 por ciento, antecedente de cirugías 30 por ciento. El 100 por ciento usaron chupón de látex, 93 por ciento utilizaron juguetes de látex y 6.6 por ciento tuvieron síntomas con el uso de látex. El análisis estadístico se realizó con pruebas no paramétricas de Kendall's tau-b: 0.329 y Spearmans rho: 0.348, las cuales fueron estadísticamente significativas. Conclusión: sí existe correlación clínica entre pruebas cutáneas y los anticuerpos IgE específicos. El antecedente de atopia es un factor predisponente; a mayor tiempo de exposición, mayor riesgo de sensibilización. La frecuencia de 4.76 por ciento es de acuerdo con lo descrito en la literatura.

[Skin reactivity in allergic conjunctivitis]. / Reactividad cutánea en conjuntivitis alérgica.

Allergic conjunctivitis is a very common disease in our country. We intend to determine the most frequent ocular involvement and the specific sensitivity to common aeroallergens. A longitudinal prospective study was performed on 20 patients from the allergy/immunology and ophthalmology outpatient service, Hospital Infantil de Mexico Federico Gomez, from May to July 1990. All of them had allergic conjunctivitis and were evaluated for ocular involvement and reactivity to common aeroallergens by skin prick test.