Improving survival by exploiting tumour dependence on stabilized mutant p53 for treatment.

Missense mutations in p53 generate aberrant proteins with abrogated tumour suppressor functions that can also acquire oncogenic gain-of-function activities that promote malignant progression, invasion, metastasis and chemoresistance. Mutant p53 (mutp53) proteins undergo massive constitutive stabilization specifically in tumours, which is the key requisite for the acquisition of gain-of-functions activities. Although currently 11 million patients worldwide live with tumours expressing highly stabilized mutp53, it is unknown whether mutp53 is a therapeutic target in vivo. Here we use a novel mutp53 mouse model expressing an inactivatable R248Q hotspot mutation (floxQ) to show that tumours depend on sustained mutp53 expression. Upon tamoxifen-induced mutp53 ablation, allotransplanted and autochthonous tumours curb their growth, thus extending animal survival by 37%, and advanced tumours undergo apoptosis and tumour regression or stagnation. The HSP90/HDAC6 chaperone machinery, which is significantly upregulated in cancer compared with normal tissues, is a major determinant of mutp53 stabilization. We show that long-term HSP90 inhibition significantly extends the survival of mutp53 Q/- (R248Q allele) and H/H (R172H allele) mice by 59% and 48%, respectively, but not their corresponding p53(-/-) littermates. This mutp53-dependent drug effect occurs in H/H mice treated with 17DMAG+SAHA and in H/H and Q/- mice treated with the potent Hsp90 inhibitor ganetespib. Notably, drug activity correlates with induction of mutp53 degradation, tumour apoptosis and prevention of T-cell lymphomagenesis. These proof-of-principle data identify mutp53 as an actionable cancer-specific drug target.

Understanding the electronic properties of BaTiO3 and Er3+ doped BaTiO3 films through confocal scanning microscopy and XPS: the role of oxygen vacancies.

Photonic and electronic properties exist inherently in ferroelectric barium titanate (BaTiO3); severe luminescence quenching also exists due to the insufficient confinement of excitons. In this sense, high optical emission can only be achieved by its chemical and structural modification. Thin BaTiO3 and Er:BaTiO3 films were grown by the spin coating method on a glass substrate at room temperature. Self-trapping of excitons in the thin BaTiO3 film and its structural modification due to the doping with Er3+ ions (Er:BaTiO3) are verified using scanning confocal fluorescence microscopy (SCFM), where self-trapping excitons never occured in its pure state. By thermal treatment and doping (BaTiO3 and Er:BaTiO3) we obtained localization of the excitons, which would further induce lattice strain around the surface defects, to accommodate the self-trapped excitons. With such a self-trapped state, the structure of BaTiO3 generates broadband emission of several overlapping bands between 1.95 and 2.65 eV at room temperature, while the structure Er:BaTiO3 showed defined emission bands at 2.24 and 2.35 eV, with very weak contributions of the emission due to the self-trapping state. The influence of the variation of the excitation wavelength using 1PE and 2PE on the emission bands of BaTiO3 and Er:BaTiO3 is also investigated. The results of enhanced emission bands suggest a clear dependence of the emission intensity on the excitation energy, where a ∼3 fold enhancement in emission has been demonstrated under Er3+ (1.55 eV) excitation, which can be attributed to effective energy transfer between the Er3+ ions. As a result, it is concluded that the developed BaTiO3 and Er:BaTiO3 can pave the way for future photonic devices.

Inflammation in metabolically healthy and metabolically abnormal adolescents: The HELENA study.

BACKGROUND AND AIMS: Inflammation may influence the cardio-metabolic profile which relates with the risk of chronic diseases. This study aimed to assess the inflammatory status by metabolic health (MH)/body mass index (BMI) category and to assess how inflammatory markers can predict the cardio-metabolic profile in European adolescents, considering BMI. METHODS AND RESULTS: A total of 659 adolescents (295 boys) from a cross-sectional European study were included. Adolescents were classified by metabolic health based on age- and sex-specific cut-off points for glucose, blood pressure, triglycerides, high density cholesterol and BMI. C-reactive protein (CRP), tumor necrosis factor alpha (TNF-α), interleukin (IL-6), complement factors (C3, C4) and cell adhesion molecules were assessed. RESULTS: Metabolically abnormal (MA) adolescents had higher values of C3 (p < 0.001) and C4 (p = 0.032) compared to those metabolically healthy (MHy). C3 concentrations significantly increased with the deterioration of the metabolic health and BMI (p < 0.001). Adolescents with higher values of CRP had higher probability of being in the overweight/obese-MH group than those allocated in other categories. Finally, high C3 and C4 concentrations increased the probability of having an unfavorable metabolic/BMI status. CONCLUSIONS: Metabolic/BMI status and inflammatory biomarkers are associated, being the CRP, C3 and C4 the most related inflammatory markers with this condition. C3 and C4 were associated with the cardio-metabolic health consistently.

Distribution of peptidergic populations in the human dentate gyrus (somatostatin [SOM-28, SOM-12] and neuropeptide Y [NPY]) during postnatal development.

The postnatal development of the human hippocampal formation establishes the time and place at which we start autobiographical memories. However, data concerning the maturation of the neurochemical phenotypes characteristic of interneurons in the human hippocampus are scarce. We have studied the perinatal and postnatal changes of the dentate gyrus (DG) interneuron populations at three rostrocaudal levels. Immunohistochemically identified neurons and fibers for somatostatin (SOM-12 and SOM-28) and neuropeptide Y (NPY) and the co-localization of SOM-28 and NPY were analyzed. In total, 13 cases were investigated from late pregnancy (1 case), perinatal period (6 cases), first year (1 case), early infancy (3 cases), and late infancy (2 cases). Overall, the pattern of distribution of these peptides in the DG was similar to that of the adult. The distribution of cells was charted, and the cell density (number of positive cells/mm(2)) was calculated. The highest density corresponded to the polymorphic cell layer and was higher at pre- and perinatal periods. At increasing ages, neuron density modifications revealed a decrease from 5 postnatal months onward. In contrast, by late infancy, two immunoreactive bands for SOM-28 and NPY in the molecular layer were much better defined. Double-immunohistochemistry showed that NPY-positive neurons co-localized with SOM-28, whereas some fibers contained only one or other of the neuropeptides. Thus, this peptidergic population, presumably inhibitory, probably has a role in DG maturation and its subsequent functional activity in memory processing.

Could a patient with SMC1A duplication be classified as a human cohesinopathy?

The disorders caused by mutations in genes encoding subunits and accessory proteins of cohesin complex are collectively termed as cohesinopathies. The best known cohesinopathy is Cornelia de Lange Syndrome (CdLS), which is a multisystem developmental disorder characterized by facial dysmorphism, limb malformations, growth and cognitive impairment. Mutations in five genes, encoding subunits of the cohesin complex (SMC1A, SMC3, RAD21) and its regulators (NIPBL, HDAC8), are responsible for ∼ 70% of CdLS cases. We describe a 16-year-old boy with facial dysmorphism, growth retardation, intellectual disability, hirsutism and small hands, who has a small Supernumerary Marker Chromosome (sSMC) present in mosaic form. sSMC is composed of two duplicated segments encompassing 17 genes including SMC1A gene, at the regions Xp11.22 and Xp11.21q11.1. Clinical comparison between our patient with a previously reported individual with a SMC1A duplication and four male carriers of similar sSMC reported in databases, suggest that they all share clinical features related to cohesinopathies. Although our patient does not have the classical CdLS craniofacial phenotype, he has pre and postnatal growth retardation, intellectual disability and mild musculoskeletal anomalies, features commonly seen in patients with cohesinopathies.

Hybrid plasmonic-photonic modes in diffractive arrays of nanoparticles coupled to light-emitting optical waveguides.

We study the hybridized plasmonic-photonic modes supported by two-dimensional arrays of metallic nanoparticles coupled to light-emitting optical waveguides. Localized surface plasmon polaritons in the metallic nanoparticles can couple to guided modes in the underlying waveguide, forming quasi-guided hybrid modes, or to diffracted orders in the plane of the array, forming surface lattice resonances. We consider three kinds of samples: one sustains quasi-guided modes only, another sustains surface lattice resonances only, and a third sample sustains both modes. This third sample constitutes the first demonstration of simultaneous coupling of localized surface plasmons to guided modes and diffracted orders. The dispersive properties of the modes in the samples are investigated through light extinction and emission spectroscopy. We elucidate the conditions that lead to the coexistence of surface lattice resonances and quasi-guided hybrid modes, and assess their potential for enhancing the luminescence of emitters embedded in the coupled waveguide. We find the largest increase in emission intensity for the surface lattice resonances, reaching up to a factor of 20.

Excitation of confined modes on particle arrays.

We describe both theoretically and experimentally the existence and excitation of confined modes in planar arrays of gold nanodisks. Ordered 2D lattices of monodispersive nanoparticles are manufactured, embedded in a silica matrix, and exposed to evanescent prism-coupling illumination, leading to dark features in the reflectivity, which signal the presence of confined modes guided along the arrays. We find remarkable agreement between theory and experiment in the frequency-momentum dispersion of the resonances. Direct excitation of these modes reveals long propagation distances and deep extinction features. This combined experimental and theoretical characterization of guided modes shows a good understanding of the optical response of metallic particles arrays, which can be beneficial in future designs of optical-signal and distant-sensing applications.

Near-field resonance at far-field-induced transparency in diffractive arrays of plasmonic nanorods.

We numerically demonstrate that a periodic array of metallic nanorods sustains a maximum near-field enhancement and a far field (FF)-induced transparency at the same energy and in-plane momentum. The coupling of bright and dark plasmonic lattice resonances, and electromagnetic retardation along the nanorod length, are responsible for this effect. A standing wave with a quadrupolar field distribution is formed, giving rise to a collective suppression of FF scattering and simultaneously enhanced local fields.

Rescue of embryonic lethality in Mdm4-null mice by loss of Trp53 suggests a nonoverlapping pathway with MDM2 to regulate p53.

The p53 protein can inhibit cell cycling or induce apoptosis, and is thus a critical regulator of tumorigenesis. This protein is negatively regulated by a physical interaction with MDM2, an E3 ubiquitin ligase. This interaction is critical for cell viability; loss of Mdm2 causes cell death in vitro and in vivo in a p53-dependent manner. The recently discovered MDM2-related protein MDM4 (also known as MDMX) has some of the same properties as MDM2. MDM4 binds and inhibits p53 transcriptional activity in vitro. Unlike MDM2, however, MDM4 does not cause nuclear export or degradation of p53 (refs. 9,10). To study MDM4 function in vivo, we deleted Mdm4 in mice. Mdm4-null mice died at 7.5-8.5 dpc, owing to loss of cell proliferation and not induction of apoptosis. To assess the importance of p53 in the death of Mdm4-/- embryos, we crossed in the Trp53-null allele. The loss of Trp53 completely rescued the Mdm4-/- embryonic lethality. Thus, MDM2 and MDM4 are nonoverlapping critical regulators of p53 in vivo. These data define a new pathway of p53 regulation and raise the possibility that increased MDM4 levels and the resulting inactivation of p53 contribute to the development of human tumors.

High endogenous melatonin concentrations enhance sperm quality and short-term in vitro exposure to melatonin improves aspects of sperm motility.

Although human seminal fluid contains melatonin and spermatozoa reportedly possess membrane melatonin receptors, there are no experimental studies that have ascertained the relationship between melatonin and male infertility. This study evaluated whether urinary 6-sulfatoxymelatonin and urinary total antioxidant capacity correlate with different seminal parameters including sperm concentration, motility and morphology. Also, the in vitro effects of melatonin on human sperm motility were investigated. Semen samples from 52 men who were counselled for infertility were obtained. Sperm concentration was determined using the haemocytometer method, motility kinematic parameters were assessed using a computer-aided semen analysis system, while morphology and vitality were evaluated after Diff-Quick and Eosin-Nigrosin vital staining, respectively. For the quantification of urinary 6-sulfatoxymelatonin, a commercial ELISA kit was used, and urinary total antioxidant capacity was evaluated by means of a colorimetric assay kit. For the in vitro effects of melatonin, samples were incubated for 30min in the presence or absence of 1mm melatonin. Both urinary 6-sulfatoxymelatonin and total antioxidant capacity levels positively correlated with sperm concentration, motility and morphology, as well as negatively correlated with the number of round cells. Additionally, 30-min exposure of sperm to 1mm melatonin improved the percentage of motile and progressively motile cells and decreased the number of static cells, thereby promoting the proportion of rapid cells. Therefore, melatonin improves semen quality, which is important because melatonin supplementation may be potentially used to obtain a successful assisted reproductive technique outcome.

High rate of autonomic neuropathy in Cornelia de Lange Syndrome.

BACKGROUND: Cornelia de Lange Syndrome (CdLS) is a rare congenital disorder characterized by typical facial features, growth failure, limb abnormalities, and gastroesophageal dysfunction that may be caused by mutations in several genes that disrupt gene regulation early in development. Symptoms in individuals with CdLS suggest that the peripheral nervous system (PNS) is involved, yet there is little direct evidence. METHOD: Somatic nervous system was evaluated by conventional motor and sensory nerve conduction studies and autonomic nervous system by heart rate variability, sympathetic skin response and sudomotor testing. CdLS Clinical Score and genetic studies were also obtained. RESULTS: Sympathetic skin response and sudomotor test were pathological in 35% and 34% of the individuals with CdLS, respectively. Nevertheless, normal values in large fiber nerve function studies. CONCLUSIONS: Autonomic nervous system (ANS) dysfunction is found in many individuals with Cornelia de Lange Syndrome, and could be related to premature aging.

The intestinal epithelium compensates for p53-mediated cell death and guarantees organismal survival.

Mdm2 is the major inhibitor of the p53 tumor suppressor. Loss of Mdm2 in mice or in specific tissues of the mouse always yields p53-dependent lethal phenotypes. However, the role of Mdm2 in tissues with high turnover capacity is unknown. We have engineered mice lacking Mdm2 in the intestinal epithelium using the Cre/LoxP system. Loss of Mdm2 (Mdm2(intDelta)) results in viable animals, but neonates display multiple intestinal abnormalities such as hyperplasia, enterocyte vacuolization, and inflammation. These defects correlate with a drastic increase in p53-dependent apoptosis in highly proliferative and differentiated cells. Unexpectedly, the observed phenotypes disappear with age. The tissue selects against Mdm2-null cells and increases its proliferative capacity. Additionally, the intestinal stem and progenitor cell populations are enriched leading to an increase in crypt fission events. Enhanced proliferation is achieved by activation of the canonical Wnt and EGFR-mediated Ras/MAPK pathways. While Mdm2 is a critical inhibitor of p53 in the intestinal epithelium, the tissue employs a series of processes that compensate for cell death.

Transcriptional activation by wild-type but not transforming mutants of the p53 anti-oncogene.

The protein encoded by the wild-type p53 proto-oncogene has been shown to suppress transformation, whereas certain mutations that alter p53 become transformation competent. Fusion proteins between p53 and the GAL4 DNA binding domain were made to anchor p53 to a DNA target sequence and to allow measurement of transcriptional activation of a reporter plasmid. The wild-type p53 stimulated transcription in this assay, but two transforming mutations in p53 were unable to act as transcriptional activators. Therefore, p53 can activate transcription, and transformation-activating mutations result in a loss of function of the p53 protein. The inability of the p53 mutant proteins to activate transcription may enable them to be transformation competent.

Optical analysis of the fine crystalline structure of artificial opal films.

Herein, we present a detailed analysis of the structure of artificial opal films. We demonstrate that, rather than the generally assumed face centered cubic lattice of spheres, opal films are better approximated by rhombohedral assemblies of distorted colloids. Detailed analysis of the optical response in a very wide spectral range (0.4 < or = a/lambda < or = 2, where a is the conventional lattice constant), as well as at perpendicular and off-normal directions, unambiguously shows that the interparticle distance coincides very approximately with the expected diameter only along directions contained in the same close-packed plane but differs significantly in directions oblique to the [111] one. A full description of the real and reciprocal lattices of actual opal films is provided, as well as of the photonic band structure of the proposed arrangement. The implications of this distortion in the optical response of the lattice are discussed.

Serum transaminases concentrations in obese children and adolescents.

The aim of the study was to investigate the relationship between liver transaminase levels and metabolic syndrome (MS) features in obese children and adolescents. A total of 132 children and adolescents (73 males and 59 females) aged 8 - 16, participated in the study. All were studied at the department of Paediatrics, University Hospital of Zaragoza (Spain). Inclusion criteria were the existence of obesity as defined by body mass index (BMI) according to Cole cut-off values (when BMI was higher than the age and sex specific equivalent to 30 kg/m2). The definition of metabolic syndrome was according to the International Diabetes Federation criteria. Weight (kg), height (cm), waist circumference (cm), blood pressure and BMI were measured. Laboratory determinations after overnight fasting included: transaminases (ALT, AST, GGT), fasting glucose, insulin, triglycerides and HDL-C. The MS was found in 21.6% of the obese children and adolescents and the prevalence was higher in males (25.9%) than in females (15.9%). Serum transaminases (ALT, AST and GGT) mean concentrations were higher in males than in females, and decreased during pubertal development. The obese children and adolescents with the MS did not show higher transaminases concentrations when compared with those without the MS. Some MS manifestations (mainly waist circumference) showed a correlation with ALT, although all transaminases values were normal according to adult references. Liver transaminases, a surrogate marker of NAFLD, did not show an early and consistent manifestation of abnormalities in the obese children and adolescents studied. In order to define the presence of the disease, it would be necessary to obtain aminotransferase reference standards for children and adolescents, considering pubertal stage and gender.

Abdominal fat and metabolic risk in obese children and adolescents.

The aim of this study was to investigate fat distribution, mainly abdominal fat, and its relationship with metabolic risk variables in a group of 126 children and adolescents (60 males and 66 females) aged 5.0 to 14.9. According to IOTF criteria, 46 were classified as normal weight, 28 overweight and 52 obese. Weight, height, waist (WC) and hip circumferences were measured. The body mass index (BMI) was calculated. Total body fat, trunkal and abdominal fat were also assessed by dual energy x-ray absorptiometry (DXA). Glucose, insulin, HDL-Cholesterol, triglycerides (TG), ferritine, homocystein and C-reactive protein (CRP) were measured. Obesity status was related with insulin concentrations, CRP, TG and HDL. Obese patients had higher abdominal fat and higher CRP values than overweight and normal subjects. All markers of central body adiposity were related with insulin and lipid metabolism; however, they were not related with homocystein or ferritin. A simple anthropometric measurement, like waist circumference, seems to be a good predictor of the majority of the obesity related metabolic risk variables.

First Report of 'Candidatus Liberibacter psyllaurous' in Potato Tubers with Zebra Chip Disease in Mexico.

Zebra Chip (ZC), an emerging disease of potato (Solanum tuberosum L.) first documented in potato fields around Saltillo in México in 1994, has been identified in the southwestern United States, México, and Central America and is causing losses of millions of dollars to the potato industry (4). Recently, this damaging potato disease was also documented in New Zealand (3). This disease is characterized by a striped pattern of necrosis in tubers produced on infected plants, and fried chips processed from these infected tubers are commercially unacceptable (4). Recent studies conducted in the United States and New Zealand have associated ZC with a new species of 'Candidatus Liberibacter' vectored by the potato psyllid, Bactericera cockerelli Sulc (1,3,4). A bacterium designated 'Candidatus Liberibacter psyllaurous' has recently been identified in potato plants with "psyllid yellows" symptoms that resemble those of ZC (2). To investigate whether liberibacter is associated with ZC in México, 11 potato (cv. Atlantic) tuber samples exhibiting strong ZC symptoms and six asymptomatic tubers were collected from a ZC-affected commercial potato field near Saltillo City, Coahuila, México in September 2008 and tested for this bacterium by PCR. Total DNA was extracted from symptomatic and asymptomatic tubers with cetyltrimethylammoniumbromide (CTAB) buffer (4). DNA samples were tested by PCR using primer pair OA2/OI2c (5'-GCGCTTATTTTTAATAGGAGCGGCA-3' and 5'-GCCTCGCGACTTCGCAACCCAT-3', respectively) specific for 16S rDNA and primer pair CL514F/R (5'-CTCTAAGATTTCGGTTGGTT-3' and 5'-TATATCTATCGTTGCACCAG-3', respectively) designed from ribosomal protein genes (3). Seven of eleven (63.7%) ZC-symptomatic tubers and one of six (16.7%) asymptomatic potatoes yielded the expected 1,168-bp 16S rDNA and 669-bp CL514F/R amplicons, indicating the presence of liberibacter. Amplicons generated from symptomatic tubers were cloned into pCR2.1-Topo plasmid vectors (Invitrogen, Carlsbad, CA) and one clone of each amplicon was sequenced in both directions (ACGT, Inc., Wheeling, IL). BLAST analysis of the ZC OA2/OI2c sequence (GenBank Accession No. FJ498806) showed 100% identity to liberibacter 16S rDNA sequences amplified from potato psyllids from Dalhart, TX and potato tubers from Garden City, KS (GenBank Accession Nos. EU921627 and EU921626, respectively). The ZC CL514F/R sequence (GenBank Accession No. FJ498807) was 98% identical to analogous rplJ and rplL liberibacter ribosomal protein gene sequences amplified from several solanaceous plants in New Zealand (GenBank Accession Nos. EU834131 and EU935005). The OA2/OI2c sequence was also identical to the 16S rDNA sequence (Genbank Accession No. EU812559) of 'Ca. Liberibacter psyllaurous' (2). To our knowledge, this is the first report of 'Ca. Liberibacter psyllaurous' associated with ZC-affected potatoes in México. References: (1) J. A. Abad et al. Plant Dis. 93:108, 2009. (2) A. K. Hansen et al. Appl. Environ. Microbiol. 74:5862, 2008. (3) L. W. Liefting et al. Plant Dis. 92:1474, 2008. (4) J. E. Munyaneza et al. J. Econ. Entomol. 100:656, 2007.

[Setting up a donor milk bank within a neonatal unit]. / Puesta en marcha del banco de leche materna donada en una unidad neonatal.

Breast milk is the best choice to feed premature and ill babies, but when there is not enough mother milk available donor breast milk is the best alternative. Nowadays, Milk Banks are present worldwide. In December 2007 the second Spanish Milk Bank opened within the Department of Neonatology of the Hospital 12 Octubre, Madrid (BLHDO). There are no international recommendations for processing breast milk, therefore other Milk Banks guidelines are the only standards to follow. BLHDO uses the Brazilian model as they focus on milk quality, in addition to safety issues. Lack of legislation for human milk processing in Spain has led to BLHDO complying with Spanish Law on blood and tissues donation with its strict regulations on safety issues and record keeping. This article summarises the first year of operating the BLHDO and its future projects and developments.

Crippling p53 activities via knock-in mutations in mouse models.

The tumor suppressor p53 is the most frequently mutated gene in human cancer. In vivo models have been generated using knock-in alleles in which missense mutations are introduced that mimic the kinds of mutations found in human cancers, or that abolish specific p53 functions. Critically, these studies examine the in vivo and physiological functions of p53. Studies indicate that p53 missense mutations in the DNA-binding domain identical with those inherited in the Li-Fraumeni syndrome, have distinct properties. Studies in mice with mutants that separate cell-cycle arrest and apoptosis functions of p53 show delayed onset of tumor development, suggesting that both p53 functions are crucial for suppressing tumors. Mice with mutations at post-translational modification sites exhibit subtle effects on p53 activity and tumor development, indicating a fine-tuning mechanism of p53 activity in vivo. Importantly, each mutant mouse has a distinct phenotype, suggesting diverse and exquisite mechanisms of p53 regulation in different environments, different tissues and different genetic backgrounds. The generation of these mutant p53 knock-in mice has laid the groundwork for future studies to elucidate the in vivo physiological function of mutant p53 and to examine cooperating effects in combination with other alterations.