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1.
Proc Biol Sci ; 290(2006): 20231668, 2023 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-37700657

RESUMEN

In anisogamous species, sexual selection is expected to be stronger in males. Bateman's principles state that the variance in (i) reproductive and (ii) mating success is greater for males, and (iii) the relationship between reproductive success and mating success (the Bateman gradient) is also stronger for males than for females. Sexual selection, based on Bateman's principles, has been demonstrated in animals and some angiosperms, but never in a seaweed. Here we focus on the oogamous haploid-diploid rhodophyte Gracilaria gracilis in which previous studies have shown evidence for non-random mating, suggesting the existence of male-male competition and female choice. We estimated mating and reproductive success using paternity analyses in a natural population where up to 92% of fertilizations occurred between partners of that population. The results show that the variance in mating success is significantly greater in males than in females and that the Bateman gradient is positive only in males. Distance to female partners also explains a minor part of the variance in male mating success. Although there is no evidence for sexual dimorphism, our study supports the hypothesis that sexual selection occurs in G. gracilis, probably on male traits, even if we cannot observe, characterize or quantify them yet.


Asunto(s)
Gracilaria , Algas Marinas , Femenino , Masculino , Animales , Selección Sexual , Caracteres Sexuales , Comunicación Celular
2.
Science ; 377(6605): 528-530, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35901149

RESUMEN

The long-held belief that animal-mediated pollination is absent in the sea has recently been contradicted in seagrasses, motivating investigations of other marine phyla. This is particularly relevant in red algae, in which female gametes are not liberated and male gametes are not flagellated. Using experiments with the isopod Idotea balthica and the red alga Gracilaria gracilis, we demonstrate that biotic interactions dramatically increase the fertilization success of the alga through animal transport of spermatia on their body. This discovery suggests that animal-mediated fertilization could have evolved independently in terrestrial and marine environments and raises the possibility of its emergence in the sea before plants moved ashore.


Asunto(s)
Gracilaria , Isópodos , Polinización , Algas Marinas , Animales , Fertilización , Gracilaria/fisiología , Algas Marinas/fisiología
4.
Dalton Trans ; 46(42): 14659-14668, 2017 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-28861553

RESUMEN

Improved bifunctional chelating agents (BFC) are required for copper-64 radiolabelling of monoclonal antibodies (mAbs) under mild conditions to yield stable, target-specific imaging agents. Four different bifunctional chelating agents (BFC) were evaluated for Fab (Fragment antigen binding) conjugation and radiolabelling with copper-64. Two DOTA- (1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid) and two NOTA- (1,4,7-triazacyclononane-1,4,7-triacetic acid) derivatives bearing a p-benzyl-isothiocyanate group were conjugated to Fab-trastuzumab - which targets the HER2/neu receptor - and the average number of chelators attached ranged from 2.4 to 4.3 macrocycles per Fab. Labelling of the immunoconjugate with copper-64 was achieved in high radiochemical yields after 45 min at 37 °C, and the radiochemical purity of each 64Cu-BFC-Fab-trastuzumab reached 97% after purification. The affinity of each 64Cu-BFC-Fab-trastuzumab ranged between 10 and 50 nM as evaluated by in vitro saturation assays using the HCC1954 breast cancer cell line. PET-MR imaging and biodistribution studies were performed in mice bearing breast cancer BT-474 xenografts. BT-474 tumours were clearly visualized on PET images at 4 and 24 hours post-injection. The tumour uptake of 64Cu-BFC-Fab-trastuzumab reached 8.9 to 12.8% ID g-1 24 hours post-injection and significant differences in non-specific liver uptake were observed depending on the BFC conjugated, the lowest being observed with MANOTA. These results show that MANOTA is a valuable tool for copper-64 radiolabelling.


Asunto(s)
Quelantes/química , Radioisótopos de Cobre , Compuestos Heterocíclicos con 1 Anillo/química , Inmunoconjugados/química , Tomografía de Emisión de Positrones/métodos , Animales , Línea Celular Tumoral , Humanos , Inmunoconjugados/farmacocinética , Fragmentos Fab de Inmunoglobulinas/química , Neoplasias Mamarias Experimentales/diagnóstico por imagen , Ratones , Distribución Tisular , Trastuzumab/química
5.
Arch Pediatr ; 16(8): 1202-7, 2009 Aug.
Artículo en Francés | MEDLINE | ID: mdl-19535231

RESUMEN

Owing to an increase in nosocomial septicaemias in the Neonatalogy department, we've judged it necessary to consider the role of items not linked to the nursing procedures, and nevertheless present in the incubators, as well as the hygiene techniques applied to them. In November 2007, we've made a longitudinal prospective study consisting in an observation audit during 3 successive days, observing every single incubator with a newborn baby. In each incubator, we've checked whether there were or not items that weren't required by the nursing activities, along with their characteristics and the hygiene procedures applied to them. We've inquired as well whether the parents and the nursing staff knew and applied the required hygiene procedures. In 13 among the 17 incubators under survey, at least one item not strictly required by the nursing procedures could be found. The number of toys in each incubator varied from seven to one. Among the 33 toys surveyed, 24 (73%) of them showed a score of maximum fluffiness (4 out of 4), and only 10 wore labels giving cleansing advice from the manufacturers. Without any record about the cleaning/disinfecting of the toys brought in hospital, we have observed that the parents were given varied advice about how to clean the toys at home before putting them in the incubators (only four parents had washed the toys in their washing machines at more than 30 degrees C). From the six samples under scrutiny, all the culture results were tested positive. In particular two of the soft toys sampled were found infected by a Pseudomonas oryzihabitans. These particular toys belonged to a baby who had been diagnosed with a septicaemia characterized by hemocultures positive to a P. oryzihabitans of a different strain. Our audit has been an efficient reminder that any item put in an incubator is a potential vector and reservoir of pathogen organisms. After a general feedback towards the department staff, the medical staff then prescribed to permanently ban all the items not strictly required by the nursing activities from all the incubators of the department.


Asunto(s)
Infección Hospitalaria/transmisión , Incubadoras para Lactantes , Auditoría Médica , Juego e Implementos de Juego , Sepsis/transmisión , Técnicas Bacteriológicas , Infección Hospitalaria/microbiología , Infección Hospitalaria/prevención & control , Estudios Transversales , Desinfección/normas , Francia , Humanos , Recién Nacido , Estudios Longitudinales , Estudios Prospectivos , Infecciones por Pseudomonas/prevención & control , Infecciones por Pseudomonas/transmisión , Factores de Riesgo , Sepsis/microbiología , Sepsis/prevención & control
6.
J Gynecol Obstet Biol Reprod (Paris) ; 37(4): 415-8, 2008 Jun.
Artículo en Francés | MEDLINE | ID: mdl-18406071

RESUMEN

Pudendal nerve block may be indicated during instrumental delivery in situations where peridural anesthesia is unavailable. We report three cases of neonatal lidocaine intoxication following maternal pudendal block during delivery. Clinical features were hypotonia, pupillary mydriasis fixed to light, apnea, cyanosis and seizures. Two neonates required mechanical ventilation. Lidocaine was found in the serum of two babies. In all three cases, recovery was complete. The pharmacokinetics of lidocaine in a highly vascularized perineum during labor increase the risk of neonatal intoxication. A possible intoxication by local anesthetics should be considered in neonates presenting an acute distress in the delivery room.


Asunto(s)
Anestesia Obstétrica/efectos adversos , Anestésicos Locales/efectos adversos , Lidocaína/efectos adversos , Anestésicos Locales/sangre , Apnea/inducido químicamente , Femenino , Humanos , Recién Nacido , Lidocaína/sangre , Masculino , Intercambio Materno-Fetal , Hipotonía Muscular/inducido químicamente , Midriasis/inducido químicamente , Bloqueo Nervioso , Embarazo , Convulsiones/inducido químicamente
7.
Mol Ecol Resour ; 8(2): 406-8, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21585804

RESUMEN

Kelps are ecologically important seaweeds that dominate the subtidal zones of rocky coasts. In Northern Europe, Saccorhiza polyschides is a pioneer species suspected of outcompeting the harvested kelp, Laminaria digitata. To examine how the process of species competition affects species distribution and genetic diversity in coastal environments, we developed 10 polymorphic microsatellite markers for S. polyschides using an enriched library (microsatellites are already available for L. digitata). These loci showed from three to 24 alleles with heterozygosities ranging from 0.36 to 0.92. This polymorphism is high enough for fine-scale population analyses including assignment tests to determine the origin of recruits.

8.
Curr Top Microbiol Immunol ; 313: 129-44, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17217042

RESUMEN

Arsenic has recently been identified as an effective drug in the treatment of newly diagnosed and relapsed acute promyelocytic leukemia. Indeed, arsenic trioxide combined with all-trans retinoic acid shows a synergistic effect. Mechanistically, arsenic targets the key leukemogenic protein PML-RARalpha, setting up a new example of molecular target-based cancer therapy.


Asunto(s)
Antineoplásicos/uso terapéutico , Arsenicales/uso terapéutico , Leucemia Promielocítica Aguda/tratamiento farmacológico , Óxidos/uso terapéutico , Antineoplásicos/administración & dosificación , Antineoplásicos/efectos adversos , Antineoplásicos/farmacocinética , Trióxido de Arsénico , Arsenicales/administración & dosificación , Arsenicales/efectos adversos , Arsenicales/farmacocinética , Ensayos Clínicos como Asunto , Humanos , Óxidos/administración & dosificación , Óxidos/efectos adversos , Óxidos/farmacocinética , Resultado del Tratamiento
9.
Mol Ecol ; 13(6): 1391-407, 2004 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15140085

RESUMEN

The distribution of genetic diversity in Mycelis muralis, or wall lettuce, was investigated at a European scale using 12 microsatellite markers to infer historical and contemporary forces from genetic patterns. Mycelis muralis has the potential for long-distance seed dispersal by wind, is mainly self-pollinated, and has patchily distributed populations, some of which may show metapopulation dynamics. A total of 359 individuals were sampled from 17 populations located in three regions, designated southern Europe (Spain and France), the Netherlands, and Sweden. At this within-region scale, contemporary evolutionary forces (selfing and metapopulation dynamics) are responsible for high differentiation between populations (0.34 < F(ST) < 0.60) but, contrary to expectation, levels of within-population diversity, estimated by Nei's unbiased expected heterozygosity (H(E)) (0.24 < H(E) < 0.68) or analyses of molecular variance (50% of the variation found within-populations), were not low. We suggest that the latter results, which are unusual in selfing species, arise from efficient seed dispersal that counteracts population turnover and thus maintains genetic diversity within populations. At the European scale, northern regions showed lower allelic richness (A = 2.38) than populations from southern Europe (A = 3.34). In light of postglacial colonization hypotheses, these results suggest that rare alleles may have been lost during recolonization northwards. Our results further suggest that mutation has contributed to genetic differentiation between southern and northern Europe, and that Sweden may have been colonized by dispersers originating from at least two different refugia.


Asunto(s)
Asteraceae/genética , Variación Genética , Genética de Población , Análisis de Varianza , Asteraceae/fisiología , Demografía , Europa (Continente) , Frecuencia de los Genes , Tamización de Portadores Genéticos , Geografía , Repeticiones de Microsatélite/genética , Datos de Secuencia Molecular , Mutación/genética , Dinámica Poblacional , Reproducción/fisiología , Viento
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