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1.
Proc Natl Acad Sci U S A ; 118(29)2021 07 20.
Artículo en Inglés | MEDLINE | ID: mdl-34230098

RESUMEN

With over 18,000 species, the Acanthomorpha, or spiny-rayed fishes, form the largest and arguably most diverse radiation of vertebrates. One of the key novelties that contributed to their evolutionary success are the spiny rays in their fins that serve as a defense mechanism. We investigated the patterning mechanisms underlying the differentiation of median fin Anlagen into discrete spiny and soft-rayed domains during the ontogeny of the direct-developing cichlid fish Astatotilapia burtoni Distinct transcription factor signatures characterize these two fin domains, whereby mutually exclusive expression of hoxa13a/b with alx4a/b and tbx2b marks the spine to soft-ray boundary. The soft-ray domain is established by BMP inhibition via gremlin1b, which synergizes in the posterior fin with shh secreted from a zone of polarizing activity. Modulation of BMP signaling by chemical inhibition or gremlin1b CRISPR/Cas9 knockout induces homeotic transformations of spines into soft rays and vice versa. The expression of spine and soft-ray genes in nonacanthomorph fins indicates that a combination of exaptation and posterior expansion of an ancestral developmental program for the anterior fin margin allowed the evolution of robustly individuated spiny and soft-rayed domains. We propose that a repeated exaptation of such pattern might underly the convergent evolution of anterior spiny-fin elements across fishes.


Asunto(s)
Aletas de Animales/metabolismo , Proteínas Morfogenéticas Óseas/metabolismo , Cíclidos/metabolismo , Proteínas de Peces/metabolismo , Proteínas Hedgehog/metabolismo , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Aletas de Animales/crecimiento & desarrollo , Animales , Evolución Biológica , Tipificación del Cuerpo , Proteínas Morfogenéticas Óseas/genética , Cíclidos/clasificación , Cíclidos/genética , Cíclidos/crecimiento & desarrollo , Proteínas de Peces/genética , Regulación del Desarrollo de la Expresión Génica , Proteínas Hedgehog/genética , Péptidos y Proteínas de Señalización Intercelular/genética , Filogenia , Transducción de Señal , Columna Vertebral/crecimiento & desarrollo , Columna Vertebral/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
2.
Dev Dyn ; 252(5): 553-588, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36351887

RESUMEN

BACKGROUND: Syngnathids are a highly derived and diverse fish clade comprising the pipefishes, pipe-horses, and seahorses. They are characterized by a plethora of iconic traits that increasingly capture the attention of biologists, including geneticists, ecologists, and developmental biologists. The current understanding of the origins of their derived body plan is, however, hampered by incomplete and limited descriptions of the early syngnathid ontogeny. RESULTS: We provide a comprehensive description of the development of Nerophis ophidion, Syngnathus typhle, and Hippocampus erectus from early cleavage stages to release from the male brooding organ and beyond, including juvenile development. We comparatively describe skeletogenesis with a particular focus on dermal bony plates, the snout-like jaw morphology, and appendages. CONCLUSIONS: This most comprehensive and detailed account of syngnathid development to date suggests that convergent phenotypes (e.g., reduction and loss of the caudal fins), likely arose by distinct ontogenetic means in pipefishes and seahorses. Comparison of the ontogenetic trajectories of S. typhle and H. erectus provides indications that characteristic features of the seahorse body plan result from developmental truncation. Altogether, this work provides a valuable resource and framework for future research to understand the evolution of the outlandish syngnathid morphology from a developmental perspective.


Asunto(s)
Smegmamorpha , Animales , Masculino , Smegmamorpha/anatomía & histología , Smegmamorpha/genética , Peces/genética , Cara
3.
Mol Ecol ; 32(21): 5798-5811, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37750351

RESUMEN

Evolutionary novelties-derived traits without clear homology found in the ancestors of a lineage-may promote ecological specialization and facilitate adaptive radiations. Examples for such novelties include the wings of bats, pharyngeal jaws of cichlids and flowers of angiosperms. Belonoid fishes (flying fishes, halfbeaks and needlefishes) feature an astonishing diversity of extremely elongated jaw phenotypes with undetermined evolutionary origins. We investigate the development of elongated jaws in a halfbeak (Dermogenys pusilla) and a needlefish (Xenentodon cancila) using morphometrics, transcriptomics and in situ hybridization. We confirm that these fishes' elongated jaws are composed of distinct base and novel 'extension' portions. These extensions are morphologically unique to belonoids, and we describe the growth dynamics of both bases and extensions throughout early development in both studied species. From transcriptomic profiling, we deduce that jaw extension outgrowth is guided by populations of multipotent cells originating from the anterior tip of the dentary. These cells are shielded from differentiation, but proliferate and migrate anteriorly during the extension's allometric growth phase. Cells left behind at the tip leave the shielded zone and undergo differentiation into osteoblast-like cells, which deposit extracellular matrix with both bone and cartilage characteristics that mineralizes and thereby provides rigidity. Such bone has characteristics akin to histological observations on the elongated 'kype' process on lower jaws of male salmon, which may hint at common conserved regulatory underpinnings. Future studies will evaluate the molecular pathways that govern the anterior migration and proliferation of these multipotent cells underlying the belonoids' evolutionary novel jaw extensions.

4.
Mol Ecol ; 32(4): 819-840, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-34951070

RESUMEN

The unique male pregnancy in pipefishes and seahorses ranges from basic attachment (pouch-less species: Nerophinae) of maternal eggs to specialized internal gestation in pouched species (e.g. Syngnathus and Hippocampus) with many transitions in between. Due to this diversity, male pregnancy offers a unique platform for assessing physiological and molecular adaptations in pregnancy evolution. These insights will contribute to answering long-standing questions of why and how pregnancy evolved convergently in so many vertebrate systems. To understand the molecular congruencies and disparities in male pregnancy evolution, we compared transcriptome-wide differentially expressed genes in four syngnathid species, at four pregnancy stages (nonpregnant, early, late and parturition). Across all species and pregnancy forms, metabolic processes and immune dynamics defined pregnancy stages, especially pouched species shared expression features akin to female pregnancy. The observed downregulation of adaptive immune genes in early-stage pregnancy and its reversed upregulation during late/parturition in pouched species, most notably in Hippocampus, combined with directionless expression in the pouch-less species, suggests immune modulation to be restricted to pouched species that evolved placenta-like systems. We propose that increased foeto-paternal intimacy in pouched syngnathids commands immune suppression processes in early gestation, and that the elevated immune response during parturition coincides with pouch opening and reduced progeny reliance. Immune response regulation in pouched species supports the recently described functional MHC II pathway loss as critical in male pregnancy evolution. The independent co-option of similar genes and pathways both in male and female pregnancy highlights immune modulation as crucial for the evolutionary establishment of pregnancy.


Asunto(s)
Smegmamorpha , Animales , Femenino , Masculino , Adaptación Fisiológica , Smegmamorpha/genética , Ovoviviparidad
5.
Nature ; 540(7633): 395-399, 2016 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-27974754

RESUMEN

Seahorses have a specialized morphology that includes a toothless tubular mouth, a body covered with bony plates, a male brood pouch, and the absence of caudal and pelvic fins. Here we report the sequencing and de novo assembly of the genome of the tiger tail seahorse, Hippocampus comes. Comparative genomic analysis identifies higher protein and nucleotide evolutionary rates in H. comes compared with other teleost fish genomes. We identified an astacin metalloprotease gene family that has undergone expansion and is highly expressed in the male brood pouch. We also find that the H. comes genome lacks enamel matrix protein-coding proline/glutamine-rich secretory calcium-binding phosphoprotein genes, which might have led to the loss of mineralized teeth. tbx4, a regulator of hindlimb development, is also not found in H. comes genome. Knockout of tbx4 in zebrafish showed a 'pelvic fin-loss' phenotype similar to that of seahorses.


Asunto(s)
Evolución Biológica , Proteínas de Peces/genética , Genoma/genética , Smegmamorpha/anatomía & histología , Smegmamorpha/genética , Aletas de Animales/anatomía & histología , Aletas de Animales/metabolismo , Animales , Secuencia Conservada/genética , Proteínas de Peces/deficiencia , Eliminación de Gen , Genómica , Miembro Posterior/anatomía & histología , Miembro Posterior/metabolismo , Masculino , Anotación de Secuencia Molecular , Familia de Multigenes/genética , Tasa de Mutación , Filogenia , Reproducción/fisiología , Proteínas de Dominio T Box/deficiencia , Proteínas de Dominio T Box/genética , Factores de Tiempo , Proteínas de Pez Cebra/deficiencia , Proteínas de Pez Cebra/genética
6.
Mol Biol Evol ; 37(11): 3165-3174, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32579214

RESUMEN

The two toothed jaws of cichlid fishes provide textbook examples of convergent evolution. Tooth phenotypes such as enlarged molar-like teeth used to process hard-shelled mollusks have evolved numerous times independently during cichlid diversification. Although the ecological benefit of molar-like teeth to crush prey is known, it is unclear whether the same molecular mechanisms underlie these convergent traits. To identify genes involved in the evolution and development of enlarged cichlid teeth, we performed RNA-seq on the serially homologous-toothed oral and pharyngeal jaws as well as the fourth toothless gill arch of Astatoreochromis alluaudi. We identified 27 genes that are highly upregulated on both tooth-bearing jaws compared with the toothless gill arch. Most of these genes have never been reported to play a role in tooth formation. Two of these genes (unk, rpfA) are not found in other vertebrate genomes but are present in all cichlid genomes. They also cluster genomically with two other highly expressed tooth genes (odam, scpp5) that exhibit conserved expression during vertebrate odontogenesis. Unk and rpfA were confirmed via in situ hybridization to be expressed in developing teeth of Astatotilapia burtoni. We then examined expression of the cluster's four genes in six evolutionarily independent and phylogenetically disparate cichlid species pairs each with a large- and a small-toothed species. Odam and unk commonly and scpp5 and rpfA always showed higher expression in larger toothed cichlid jaws. Convergent trophic adaptations across cichlid diversity are associated with the repeated developmental deployment of this genomic cluster containing conserved and novel cichlid-specific genes.


Asunto(s)
Evolución Biológica , Cíclidos/genética , Diente/crecimiento & desarrollo , Animales , Cíclidos/crecimiento & desarrollo , Familia de Multigenes
7.
Strahlenther Onkol ; 197(9): 802-811, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33320286

RESUMEN

PURPOSE: Hypofractionated radiotherapy is the standard of care for adjuvant whole breast radiotherapy (RT). However, adoption has been slow. The indication for regional nodal irradiation has been expanded to include patients with 0-3 involved lymph nodes. We investigated the impact of the publication of the updated German S3 guidelines in 2017 on adoption of hypofractionation and enrollment of patients with lymph node involvement within a randomized controlled phase III trial. METHODS: In the experimental arm of the HYPOSIB trial (NCT02474641), hypofractionated RT with simultaneous integrated boost (SIB) was used. In the standard arm, RT could be given as hypofractionated RT with sequential boost (HFseq), normofractionated RT with sequential boost (NFseq), or normofractionated RT with SIB (NFSIB). The cutoff date for the updated German S3 guidelines was December 17, 2017. Temporal trends were analyzed by generalized linear regression models. Multiple logistic regression models were used to investigate the influence of time (prior to/after guideline) and setting (university hospital/other institutions) on the fractionation patterns. RESULTS: Enrollment of patients with involved lymph nodes was low throughout the trial. Adoption of HFseq increased over time and when using the guideline publication date as cutoff. Results of the multiple logistic regressions showed an interaction between time and setting. Furthermore, the use of HFseq was significantly more common in university hospitals. CONCLUSION: The use of HFseq in the standard arm increased over the course of the HYPOSIB trial and after publication of the S3 guideline update. This was primarily driven by patients treated in university hospitals. Enrolment of patients with lymph node involvement was low throughout the trial.


Asunto(s)
Neoplasias de la Mama , Hipofraccionamiento de la Dosis de Radiación , Neoplasias de la Mama/patología , Neoplasias de la Mama/radioterapia , Fraccionamiento de la Dosis de Radiación , Femenino , Humanos , Modelos Logísticos , Radioterapia Adyuvante/métodos
8.
J Struct Biol ; 209(1): 107403, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31614182

RESUMEN

Unicellular protists can biomineralize spatially complex and functional shells. A typical cell of the photosynthetic synurophyte Mallomonas is covered by about 60-100 silica scales. Their geometric arrangement, the so-called scale case, mainly depends on the species and on the cell cycle. In this study, the scale case of the synurophyte Mallomonas was preserved in aqueous suspension using high-pressure freezing (HPF). From this specimen, a three-dimensional (3D) data set spanning a volume of about 25.6 µm × 19.2 µm × 4.2 µm with a voxel size of 12.5 nm × 12.5 nm × 25.0 nm was collected by Cryo-FIB SEM in 3 h and 24 min. SEM imaging using In-lens SE detection allowed to clearly differentiate between mineralized, curved scales of less than 0.2 µm thickness and organic cellular ultrastructure or vitrified ice. The three-dimensional spatial orientations and shapes of a minimum set of scales (N = 13) were identified by visual inspection, and manually segmented. Manual and automated segmentation approaches were comparatively applied to one arbitrarily selected reference scale using the differences in grey level between scales and other constituents. Computational automated routines and principal component analysis of the experimentally extracted data created a realistic mathematical model based on the Fibonacci pattern theory. A complete in silico scale case of Mallomonas was reconstructed showing an optimized scale coverage on the cell surface, similarly as it was observed experimentally. The minimum time requirements from harvesting the living cells to the final scale case determination by Cryo-FIB SEM and computational image processing are discussed.


Asunto(s)
Chrysophyta/ultraestructura , Microscopía por Crioelectrón , Imagenología Tridimensional , Chrysophyta/fisiología , Procesamiento de Imagen Asistido por Computador , Microscopía Electrónica de Rastreo
9.
Mol Biol Evol ; 36(11): 2498-2511, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31397871

RESUMEN

Cichlid fishes provide textbook examples of explosive phenotypic diversification and sympatric speciation, thereby making them ideal systems for studying the molecular mechanisms underlying rapid lineage divergence. Despite the fact that gene regulation provides a critical link between diversification in gene function and speciation, many genomic regulatory mechanisms such as microRNAs (miRNAs) have received little attention in these rapidly diversifying groups. Therefore, we investigated the posttranscriptional regulatory role of miRNAs in the repeated sympatric divergence of Midas cichlids (Amphilophus spp.) from Nicaraguan crater lakes. Using miRNA and mRNA sequencing of embryos from five Midas species, we first identified miRNA binding sites in mRNAs and highlighted the presences of a surprising number of novel miRNAs in these adaptively radiating species. Then, through analyses of expression levels, we identified putative miRNA/gene target pairs with negatively correlated expression level that were consistent with the role of miRNA in downregulating mRNA. Furthermore, we determined that several miRNA/gene pairs show convergent expression patterns associated with the repeated benthic/limnetic sympatric species divergence implicating these miRNAs as potential molecular mechanisms underlying replicated sympatric divergence. Finally, as these candidate miRNA/gene pairs may play a central role in phenotypic diversification in these cichlids, we characterized the expression domains of selected miRNAs and their target genes via in situ hybridization, providing further evidence that miRNA regulation likely plays a role in the Midas cichlid adaptive radiation. These results provide support for the hypothesis that extremely quickly evolving miRNA regulation can contribute to rapid evolutionary divergence even in the presence of gene flow.

10.
Mol Ecol ; 29(7): 1219-1234, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31710745

RESUMEN

Sympatric speciation occurs without geographical barriers and is thought to often be driven by ecological specialization of individuals that eventually diverge genetically and phenotypically. Distinct morphologies between sympatric populations occupying different niches have been interpreted as such differentiating adaptive phenotypes, yet differences in performance and thus likely adaptiveness between them were rarely tested. Here, we investigated if divergent body shapes of two sympatric crater lake cichlid species from Nicaragua, one being a shore-associated (benthic) species while the other prefers the open water zones (limnetic), affect cruising (Ucrit ) and sprinting (Usprint ) swimming abilities - performances particularly relevant to their respective lifestyles. Furthermore, we investigated species differences in oxygen consumption (MO2 ) across different swimming speeds and compare gene expression in gills and white muscle at rest and during exercise. We found a superior cruising ability in the limnetic Amphilophus zaliosus compared to the benthic Amphilophus astorquii, while sprinting was not different, suggesting that their distinct morphologies affect swimming performance. Increased cruising swimming ability in A. zaliosus was linked to a higher oxygen demand during activity (but not rest), indicating different metabolic rates during exercise - a hypothesis supported by coinciding gene expression patterns of gill transcriptomes. We identified differentially expressed genes linked to swimming physiology, regulation of swimming behaviour and oxygen intake. A combination of physiological and morphological differences may thus underlie adaptations to these species' distinct niches. This complex ecological specialization probably resulted in morphological and physiological trade-offs that contributed to the rapid establishment and maintenance of divergence with gene flow.


Asunto(s)
Cíclidos/genética , Cíclidos/fisiología , Natación/fisiología , Simpatría , Adaptación Fisiológica , Animales , Tamaño Corporal , Cíclidos/clasificación , Expresión Génica , Branquias , Lagos , Nicaragua , Consumo de Oxígeno , Fenotipo , Especificidad de la Especie , Transcriptoma
11.
BMC Dev Biol ; 18(1): 8, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29614958

RESUMEN

BACKGROUND: The experimental approach to the evolution and development of the vertebrate skeleton has to a large extent relied on "direct-developing" amniote model organisms, such as the mouse and the chicken. These organisms can however only be partially informative where it concerns secondarily lost features or anatomical novelties not present in their lineages. The widely used anamniotes Xenopus and zebrafish are "indirect-developing" organisms that proceed through an extended time as free-living larvae, before adopting many aspects of their adult morphology, complicating experiments at these stages, and increasing the risk for lethal pleiotropic effects using genetic strategies. RESULTS: Here, we provide a detailed description of the development of the osteology of the African mouthbrooding cichlid Astatotilapia burtoni, primarily focusing on the trunk (spinal column, ribs and epicentrals) and the appendicular skeleton (pectoral, pelvic, dorsal, anal, caudal fins and scales), and to a lesser extent on the cranium. We show that this species has an extremely "direct" mode of development, attains an adult body plan within 2 weeks after fertilization while living off its yolk supply only, and does not pass through a prolonged larval period. CONCLUSIONS: As husbandry of this species is easy, generation time is short, and the species is amenable to genetic targeting strategies through microinjection, we suggest that the use of this direct-developing cichlid will provide a valuable model system for the study of the vertebrate body plan, particularly where it concerns the evolution and development of fish or teleost specific traits. Based on our results we comment on the development of the homocercal caudal fin, on shared ontogenetic patterns between pectoral and pelvic girdles, and on the evolution of fin spines as novelty in acanthomorph fishes. We discuss the differences between "direct" and "indirect" developing actinopterygians using a comparison between zebrafish and A. burtoni development.


Asunto(s)
Huesos/anatomía & histología , Cíclidos/anatomía & histología , Cíclidos/embriología , Modelos Biológicos , Aletas de Animales/anatomía & histología , Aletas de Animales/embriología , Escamas de Animales/anatomía & histología , Escamas de Animales/embriología , Animales , Evolución Biológica , Desarrollo Embrionario , Osteogénesis
12.
Mol Ecol ; 26(1): 330-350, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27747962

RESUMEN

There is increasing evidence that phenotypic plasticity can promote population divergence by facilitating phenotypic diversification and, eventually, genetic divergence. When a 'plastic' population colonizes a new habitat, it has the possibility to occupy multiple niches by expressing several distinct phenotypes. These initially reflect the population's plastic range but may later become genetically fixed by selection via the process of 'genetic assimilation' (GA). Through this process multiple specialized sister lineages can arise that share a common plastic ancestor - the 'flexible stem'. Here, we review possible molecular mechanisms through which natural selection could fix an initially plastic trait during GA. These mechanisms could also explain how GA may contribute to cryptic genetic variation that can subsequently be coopted into other phenotypes or traits, but also lead to nonadaptive responses. We outline the predicted patterns of genetic and transcriptional divergence accompanying flexible stem radiations. The analysis of such patterns of (retained) adaptive and nonadaptive plastic responses within and across radiating lineages can inform on the state of ongoing GA. We conclude that, depending on the stability of the environment, the molecular architecture underlying plastic traits can facilitate diversification, followed by fixation and consolidation of an adaptive phenotype and degeneration of nonadaptive ones. Additionally, the process of GA may increase the cryptic genetic variation of populations, which on one hand may serve as substrate for evolution, but on another may be responsible for nonadaptive responses that consolidate local allopatry and thus reproductive isolation.


Asunto(s)
Adaptación Biológica/genética , Variación Genética , Modelos Genéticos , Selección Genética , Evolución Biológica , Fenotipo , Aislamiento Reproductivo
13.
Mol Ecol ; 26(23): 6634-6653, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29098748

RESUMEN

Adaptive radiations are characterized by adaptive diversification intertwined with rapid speciation within a lineage resulting in many ecologically specialized, phenotypically diverse species. It has been proposed that adaptive radiations can originate from ancestral lineages with pronounced phenotypic plasticity in adaptive traits, facilitating ecologically driven phenotypic diversification that is ultimately fixed through genetic assimilation of gene regulatory regions. This study aimed to investigate how phenotypic plasticity is reflected in gene expression patterns in the trophic apparatus of several lineages of East African cichlid fishes, and whether the observed patterns support genetic assimilation. This investigation used a split brood experimental design to compare adaptive plasticity in species from within and outside of adaptive radiations. The plastic response was induced in the crushing pharyngeal jaws through feeding individuals either a hard or soft diet. We find that nonradiating, basal lineages show higher levels of adaptive morphological plasticity than the derived, radiated lineages, suggesting that these differences have become partially genetically fixed during the formation of the adaptive radiations. Two candidate genes that may have undergone genetic assimilation, gif and alas1, were identified, in addition to alterations in the wiring of LPJ patterning networks. Taken together, our results suggest that genetic assimilation may have dampened the inducibility of plasticity related genes during the adaptive radiations of East African cichlids, flattening the reaction norms and canalizing their feeding phenotypes, driving adaptation to progressively more narrow ecological niches.


Asunto(s)
Adaptación Biológica/genética , Cíclidos/clasificación , Especiación Genética , Maxilares/anatomía & histología , África Oriental , Animales , Cíclidos/anatomía & histología , Dieta , Conducta Alimentaria , Proteínas de Peces/genética , Fenotipo
14.
Pediatr Blood Cancer ; 64(12)2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28627000

RESUMEN

BACKGROUND: Few data exist regarding the clinical outcome of patients with Ewing sarcoma (EWS) treated with pencil beam scanning proton therapy (PT). We report the outcome of children, adolescents and young adults (AYA) treated with PT at the Paul Scherrer Institute. MATERIALS: Thirty-eight patients (median age, 9.9 years) received a median dose of 54.9 Gy(RBE) (where RBE is relative biologic effectiveness). Size of the tumor ranged from 1.7 to 24 cm. Most common primary site was axial/pelvic (n = 27; 71%). Four patients (11%) presented with metastases at diagnosis. Twenty (53%) patients had chemo-PT only. Median follow-up was 49.6 months (range, 9.2-131.7). RESULTS: The 5-year actuarial rate of local control (LC), distant metastasis-free survival (DMFS), and overall survival (OS) were 81.5%, 76.4%, and 83.0%, respectively. All local recurrences occurred in field and in patients with nonextremity primaries. Six patients died, all of tumor progression. Age < 10 years was a favorable factor of borderline significance for LC (P = 0.05) and OS (P = 0.05), but was significant for DMFS (P = 0.003). Tumor volume <200 ml was a significant prognostic factors for DMFS (P = 0.03), but not for OS (P = 0.07). Metastasis at diagnosis was a strong predictor of local failure (P = 0.003). Only two grade 3 late toxicities were observed. The 5-year actuarial rate of grade 3 toxicity-free survival was 90.9%. CONCLUSIONS: These preliminary data suggest that the outcomes of children and AYA with EWS are good and PT was well tolerated with few late adverse events. The local and distant tumor control for older patients with large pre-PT tumor volumes remains problematic.


Asunto(s)
Neoplasias Óseas/radioterapia , Terapia de Protones , Sarcoma de Ewing/radioterapia , Adolescente , Adulto , Neoplasias Óseas/mortalidad , Neoplasias Óseas/patología , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Sarcoma de Ewing/mortalidad , Sarcoma de Ewing/patología , Carga Tumoral , Adulto Joven
15.
Anal Chem ; 88(17): 8624-31, 2016 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-27373999

RESUMEN

Simple, fast, and versatile methods for the quantification of thiol groups are of considerable interest not only for protein analysis but also for the characterization of the surface chemistry of nanomaterials stabilized with thiol ligands or bearing thiol groups for the subsequent (bio-) functionalization via maleimide-thiol chemistry. Here, we compare two simple colorimetric assays, the widely used Ellman's assay performed at alkaline pH and the aldrithiol assay executed at acidic and neutral pH, with respect to their potential for the quantification of thiol groups and thiol ligands on different types of nanoparticles like polystyrene nanoparticles, semiconductor nanocrystals (SC NC), and noble metal particles, and we derive criteria for their use. In order to assess the underlying reaction mechanisms and to obtain stoichiometry factors mandatory for reliable thiol quantification, both methods were studied photometrically and with electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS), thereby demonstrating the influence of different thiols on the reaction mechanism. Our results underline the suitability of both methods for the quantification of directly accessible thiol groups or ligands on the surface of 2D- and 3D-supports, here exemplarily polystyrene nanoparticles. Moreover, we could derive strategies for the use of these simple assays for the determination of masked (i.e., not directly accessible) thiol groups like disulfides such as lipoic acid and thiol stabilizing ligands coordinatively bound to Cd and/or Hg surface atoms of II/VI and ternary SC NC and to gold and silver nanoparticles.

16.
J Neurooncol ; 127(3): 597-606, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26852221

RESUMEN

In this retrospective evaluation, we correlated radiation dose parameters with occurrence of optical radiation-induced toxicities. 213 meningioma patients received radiation between 2000 and 2013. Radiation dose and clinical data were extracted from planning systems and patients' files. The range of follow-up period was 2-159 months (median 75 months). Median age of patients was 60 years (range 23-86). There were 163 female and 50 male patients. In 140 cases, at least one of the neuro-optic structures (optic nerves and chiasm) was inside the irradiated target volumes. We found 15 dry eye (7 %) and 24 cataract (11.2 %) cases. Median dose to affected lachrymal glands was 1.47 Gy and median dose to affected lenses was 1.05 Gy. Age and blood cholesterol level in patients with cataract were significantly higher. Patients with dry eye were significantly older. Only two patients with visual problems attributable to radiation treatment were seen. They did not have any risk factors. Maximum and median delivered doses to neuro-optic structures were not higher than 57.30 and 54.60 Gy respectively. Low percentages of cases with radiation induced high grade optic toxicities show that modern treatment techniques and doses are safe. In very few patients with optic side effects, doses to organs at risk were higher than the defined constraint doses. This observation leads to the problem of additional risk factors coming into play. The role of risk factors and safety of higher radiation doses in high grade meningiomas should be investigated in more comprehensive studies.


Asunto(s)
Neoplasias Meníngeas/radioterapia , Meningioma/radioterapia , Enfermedades del Nervio Óptico/etiología , Nervio Óptico/efectos de la radiación , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Neoplasias Meníngeas/patología , Meningioma/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Enfermedades del Nervio Óptico/diagnóstico , Pronóstico , Traumatismos por Radiación/diagnóstico , Dosificación Radioterapéutica , Estudios Retrospectivos , Adulto Joven
17.
Bioorg Med Chem Lett ; 26(15): 3436-40, 2016 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-27374241

RESUMEN

The major clinical challenge in drug-resistant chronic myelogenous leukemia (CML) is currently represented by the Bcr-Abl T315I mutant, which is unresponsive to treatment with common first and second generation ATP-competitive tyrosine kinase inhibitors (TKIs). Allosteric inhibition of Bcr-Abl represent a new frontier in the fight against resistant leukemia and few candidates have been identified in the last few years. Among these, myristate pocket (MP) binders discovered by Novartis (e.g. GNF2/5) showed promising results, although they proved to be active against the T315I mutant only in combination with first and second generation ATP-competitive inhibitors. Here we used a cascade screening approach based on sequential fluorescence polarization (FP) screening, in silico docking/dynamics studies and kinetic-enzymatic studies to identify novel MP binders. A pyrazolo[3,4-d]pyrimidine derivative (6) has been identified as a promising allosteric inhibitor active on 32D leukemia cell lines (expressing Bcr-Abl WT and T315I) with no need of combination with any ATP-competitive inhibitor.


Asunto(s)
Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Proteínas de la Membrana/antagonistas & inhibidores , Miristatos/farmacología , Proteínas de Neoplasias/antagonistas & inhibidores , Regulación Alostérica/efectos de los fármacos , Muerte Celular/efectos de los fármacos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Leucemia Mielógena Crónica BCR-ABL Positiva/patología , Proteínas de la Membrana/genética , Modelos Moleculares , Estructura Molecular , Mutación , Miristatos/síntesis química , Miristatos/química , Proteínas de Neoplasias/genética , Relación Estructura-Actividad
18.
Pediatr Blood Cancer ; 63(10): 1731-6, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-26701148

RESUMEN

BACKGROUND: Parameningeal rhabdomyosarcomas (PM-RMSs) represent approximately 25% of all rhabdomyosarcoma (RMS) cases. These tumors are associated with early recurrence and poor prognosis. This study assessed the clinical outcome and late toxicity of pencil beam scanning (PBS) proton therapy (PT) in the treatment of children with PM-RMS. PROCEDURES: Thirty-nine children with PM-RMS received neoadjuvant chemotherapy followed by PBS-PT at the Paul Scherrer Institute, with concomitant chemotherapy. The median age was 5.8 years (range, 1.2-16.1). Due to young age, 25 patients (64%) required general anesthesia during PT. The median time from the start of chemotherapy to PT was 13 weeks (range, 3-23 weeks). Median prescription dose was 54 Gy (relative biologic effectiveness, RBE). RESULTS: With a mean follow-up of 41 months (range, 9-106 months), 10 patients failed. The actuarial 5-year progression-free survival (PFS) was 72% (95% CI, 67-94%) and the 5-year overall survival was 73% (95% CI, 69-96%). On univariate analysis, a delay in the initiation of PT (>13 weeks) was a significant detrimental factor for PFS. Three (8%) patients presented with grade 3 radiation-induced toxicity. The estimated actuarial 5-year toxicity ≥grade 3 free survival was 95% (95% CI, 94-96%). CONCLUSIONS: Our data contribute to the growing body of evidence demonstrating the safety and effectiveness of PT for pediatric patients with PM-RMS. These preliminary results are encouraging and in line with other combined proton-photon and photons series; observed toxicity was acceptable.


Asunto(s)
Terapia de Protones/métodos , Rabdomiosarcoma Embrionario/radioterapia , Adolescente , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Planificación de la Radioterapia Asistida por Computador , Efectividad Biológica Relativa , Rabdomiosarcoma Embrionario/mortalidad , Insuficiencia del Tratamiento
19.
Artículo en Alemán | MEDLINE | ID: mdl-26859470

RESUMEN

Zinc phosphide normally serves as a rodenticide but is occasionally ingested for suicide, potentially causing multiorgan failure. Phosphine gas is commonly in use for fumigation of grain silos and shipping containers.We describe a suicide attempt of a 54 year old female, the clinical symptoms, the treatment, the chemical and biochemical background and we give information on the potential occurrence of zinc phosphide and phosphine gas.


Asunto(s)
Fosfinas/envenenamiento , Rodenticidas/envenenamiento , Intento de Suicidio , Compuestos de Zinc/envenenamiento , Cuidados Críticos , Ingestión de Alimentos , Femenino , Hospitalización , Humanos , Persona de Mediana Edad
20.
J Neurooncol ; 121(2): 389-97, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25362544

RESUMEN

The aim of this analysis was to assess the early clinical results of pencil beam scanning proton therapy (PT) in the treatment of young children with non-metastatic atypical teratoid/rhabdoid tumor (ATRT) of the CNS. Fifteen children (male, n = 8, 53 %) were treated with PT between May 2008 and January 2013. Mean age at diagnosis was 17.4 ± 7.0 months. The localization was infratentorial in 9 (60 %) patients. Gross total resection of the primary tumors was achieved in 7 (47 %) patients. The dose administered focally under sedation was 54 Gy (RBE). After a median follow-up of 33.4 months (range 9.7-69.2), 3 (20 %), 4 (27 %) and 2 (13 %) patients presented with local failure (LF), distant brain failure (DBF) and spinal failure (SF), respectively. Six patients died, all of tumor progression. The 2-year overall- and progression-free survival was 64.6 and 66.0 %. Tumor location (supratentorial) and the extent of surgical resection (non-gross total resection) were negative prognostic factors for both OS and PFS. PT was well tolerated. No grade >2 acute toxicity was observed. The estimated 2-year toxicity-free survival was 90 %. As assessed by the PedsQoL proxy, no decrease in QoL was observed after PT. We conclude that PBS PT is an effective treatment for young children with ATRT. After PT, with or without concomitant chemotherapy, two third of the patients survived >2 years. Acute toxicity was manageable. Longer follow-up and larger numbers of patients are needed to assess long-term outcomes and treatment-induced toxicity.


Asunto(s)
Neoplasias del Sistema Nervioso Central/tratamiento farmacológico , Neoplasias del Sistema Nervioso Central/radioterapia , Terapia de Protones , Tumor Rabdoide/tratamiento farmacológico , Tumor Rabdoide/radioterapia , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Encéfalo/cirugía , Neoplasias del Sistema Nervioso Central/psicología , Neoplasias del Sistema Nervioso Central/cirugía , Preescolar , Terapia Combinada/efectos adversos , Supervivencia sin Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Lactante , Masculino , Pronóstico , Terapia de Protones/efectos adversos , Terapia de Protones/métodos , Calidad de Vida , Planificación de la Radioterapia Asistida por Computador , Tumor Rabdoide/psicología , Tumor Rabdoide/cirugía , Resultado del Tratamiento
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